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Can FOXOs modulate longevity?

FOXOs are reliable markers of longevity.

FOXO transcription factors have important roles in metabolism, cellular proliferation, stress tolerance, and aging. FOXOs are negatively regulated by protein kinase B/c-Akt-mediated phosphorylation. Here we show that FOXO factors are also subject to regulation by reversible acetylation. We provide evidence that the acetyltransferase CREB-binding protein (CBP) binds FOXO resulting in acetylation of FOXO. This acetylation inhibits FOXO transcriptional activity. Binding of CBP and acetylation are induced after treatment of cells with peroxide stress. Deacetylation of FOXOs involves binding of the NAD-dependent deacetylase hSir2(SIRT1). Accordingly, hSir2(SIRT1)-mediated deacetylation precludes FOXO inhibition through acetylation and thereby prolongs FOXO-dependent transcription of stress-regulating genes. These data demonstrate that acetylation functions in a second pathway of negative control for FOXO factors and provides a novel mechanism whereby hSir2(SIRT1) can promote cellular survival and increase lifespan. OBJECTIVE: Although the quest for longevity is as old as civilization itself, only recently have technical and conceptual advances in genomics research brought us to the point of understanding the precise molecular events that make us age. This heralds an era when manipulations of these will enable us to live longer, healthier lives. The present review describes how recent experimental strategies have identified key genes and intracellular pathways that are responsible for ageing and longevity. FINDINGS: In diverse species transcription factors belonging to the forkhead/winged helix box gene, group O (FOXO) subfamily have been found to be crucial in downstream suppression of the life-shortening effects of insulin/insulin-like growth factor-I receptor signalling pathways that, when upregulated, accelerate ageing by suppression of FOXO. The various adverse processes activated upon FOXO suppression include increased generation of reactive oxygen species (ROS). ROS are pivotal for the onset of various common conditions, including hypertension, atherosclerosis, type 2 diabetes, cancer and Alzheimer's disease, each of which shortens lifespan. In humans, FOXO3a, as well as FOXO1 and -4, and their downstream effectors, could hold the key to counteracting ageing and common diseases. An understanding of the processes controlled by these FOXOs should permit development of novel classes of agents that will more directly counteract or prevent the damage associated with diverse life-threatening conditions, and so foster a life of good health to a ripe old age. Just like caloric restriction, lifespan can be increased in various species by plant-derived polyphenols, such as resveratrol, via activation of sirtuins in cells. Sirtuins, such as SIRT1 in mammals, utilize FOXO and other pathways to achieve their beneficial effects on health and lifespan. CONCLUSION: Lifespan is tractable and basic mechanisms are now known. Longevity research complements and overlaps research in most major medical disciplines. Current progress bodes well for an ever-increasing length of healthy life for those who adapt emerging knowledge personally (so-called 'longevitarians'). The forkhead O (FoxO) family of transcription factors participates in diverse physiologic processes, including induction of cell-cycle arrest, stress resistance, differentiation, apoptosis, and metabolism. Several recent studies indicate that FoxO-dependent signaling is required for long-term regenerative potential of the hematopoietic stem cell (HSC) compartment through regulation of HSC response to physiologic oxidative stress, quiescence, and survival. These observations link FoxO function in mammalian systems with the evolutionarily conserved role of FoxO in promotion of stress resistance and longevity in lower phylogenetic systems. Furthermore, these findings have implications for aging in higher organisms and in maligt stem cell biology, and suggest that FoxOs may play an important role in the maintece and integrity of stem cell compartments in a broad spectrum of tissues. Given that cancer and related disorders affect a wide spectrum of the world's population, and in most cases are progressive in nature, it is essential that future care must overcome the present limitations of existing therapies in the absence of toxic side effects. Mammalian forkhead transcription factors of the O class (FoxOs) may fill this niche since these proteins are increasingly considered to represent unique cellular targets directed against human cancer in light of their pro-apoptotic effects and ability to lead to cell cycle arrest. Yet, FoxOs also can significantly affect normal cell survival and longevity, requiring new treatments for neoplastic growth to modulate novel pathways that integrate cell proliferation, metabolism, inflammation and survival. In this respect, members of the FoxO family are extremely compelling to consider since these transcription factors have emerged as versatile proteins that can control angiogenesis, stem cell proliferation, cell adhesion and autoimmune disease. Further elucidation of FoxO protein function during neoplastic growth should continue to lay the foundation for the successful translation of these transcription factors into novel and robust clinical therapies for cancer. INTRODUCTION: The aging process represents a progressive decline in cellular and organism function. Explaining the aging process has given rise to a cornucopia for different theories in which the basic difference has been the question whether aging is genetically regulated or an entropic degeneration process. DISCUSSION: Different screening techniques have revealed that mammalian aging is associated with the activation of NF-kappaB transcription factor system. The NF-kappaB system is an ancient host defense system concerned with immune responses and different external and internal dangers, such as oxidative and genotoxic stress. NF-kappaB signaling is not only the master regulator of inflammatory responses but can also regulate several homeostatic responses such as apoptosis, autophagy, and tissue atrophy. We will describe how chronic activation of NF-kappaB signaling has the capacity to induce the senescent phenotype associated with aging. Interestingly, several longevity genes such as SIRT1, SIRT6, and FoxOs can clearly suppress NF-kappaB signaling and in this way delay the aging process and extend lifespan. CONCLUSION: It seems that the aging process is an entropic degeneration process driven by NF-kappaB signaling. This process can be regulated by a variety of longevity genes along with a plethora of other factors such as genetic polymorphism, immune and dietary aspects, and environmental insults. GH/insulin/IGF-1 signaling is a vital pathway e.g. in the regulation of protein synthesis and glucose metabolism. However, mouse dwarf strains which exhibit reduced GH secretion and subsequently a decline in IGF-1 signaling can live longer than their wild type counterparts. There is striking evidence indicating that the IGF-1/PI-3K/AKT signaling enhances growth of animals during development but later in life can potentiate the aging process. This conserved pleiotropy has been called the insulin/IGF-1 paradox. In Caenorhabditiselegans, the decline in this pathway activates the DAF-16 gene, an ortholog of mammalian FoxO genes, which regulate stress resistance and longevity. The mammalian PI-3K/AKT pathway also activates the NF-kappaB signaling that inhibits apoptosis and triggers inflammatory responses. Many longevity genes, e.g. FoxOs and SIRT1, are inhibitors of NF-kappaB signaling. We will discuss the evidence that insulin/IGF-1 signaling can enhance the NF-kappaB signaling and subsequently potentiate the aging process and aggravate age-related degenerative diseases. Advances in clinical care for disorders involving any system of the body necessitates novel therapeutic strategies that can focus upon the modulation of cellular proliferation, metabolism, inflammation and longevity. In this respect, members of the mammalian forkhead transcription factors of the O class (FoxOs) that include FoxO1, FoxO3, FoxO4 and FoxO6 are increasingly being recognized as exciting prospects for multiple disorders. These transcription factors govern development, proliferation, survival and longevity during multiple cellular environments that can involve oxidative stress. Furthermore, these transcription factors are closely integrated with several novel signal transduction pathways, such as erythropoietin and Wnt proteins, that may influence the ability of FoxOs to act as a "double-edge sword" to sometimes promote cell survival, but at other times lead to cell injury. Here we discuss the fascinating but complex role of FoxOs during cellular injury and oxidative stress, progenitor cell development, fertility, angiogenesis, cardiovascular function, cellular metabolism and diabetes, cell longevity, immune surveillance and cancer. Forkhead box O (FOXO) transcription factors are involved in various cellular processes, including cell proliferation, stress resistance, metabolism, and longevity. Regulation of FOXO transcriptional activity occurs mainly through a variety of post-translational modifications, including phosphorylation, acetylation, and ubiquitination. Here we describe nemo-like kinase (NLK) as a novel regulator of FOXOs. NLK binds to and phosphorylates FOXO1, FOXO3a, and FOXO4 on multiple residues. NLK acts as a negative regulator of FOXO transcriptional activity. For FOXO4 we show that NLK-mediated loss of FOXO4 activity co-occurs with inhibition of FOXO4 monoubiquitination. Previously, we have shown that oxidative stress-induced monoubiquitination of FOXO4 stimulates its transactivation, which leads to activation of an antioxidant defensive program. Conversely, NLK-dependent inhibition of FOXO4 activity can provide a means to downregulate this defensive program, when oxidative stress reaches a level beyond which repair is no longer feasible and cells need to undergo apoptosis. This review focuses on the interrelationship between ageing and autophagy. There is a striking similarity between the signalling aspects of these two processes. Both ageing and autophagy involve several of the signalling components such as insulin/IGF-1, AMPK, Ras-cAMP-PKA, Sch9 and mTOR. Ageing and ageing-mediated defective autophagy involve accumulation of lipofuscin. Components of anti-ageing and autophagy include SirTs and FoxOs. Nutritional deprivation or calorie restriction as well as several nutriceuticals including resveratrol, spermidine, curcumin and piperine can enhance autophagy and increase lifespan. Such striking similarities indicate that lifespan is strongly dependent on autophagy. Adenosine monophosphate-activated protein kinase (AMPK) is a crucial regulator of energy metabolic homeostasis and thus a major survival factor in a variety of metabolic stresses and also in the aging process. Metabolic syndrome is associated with a low-grade, chronic inflammation, primarily in adipose tissue. A low-level of inflammation is also present in the aging process. There are emerging results indicating that AMPK signaling can inhibit the inflammatory responses induced by the nuclear factor-κB (NF-κB) system. The NF-κB subunits are not direct phosphorylation targets of AMPK, but the inhibition of NF-κB signaling is mediated by several downstream targets of AMPK, e.g., SIRT1, PGC-1α, p53, and Forkhead box O (FoxO) factors. AMPK signaling seems to enhance energy metabolism while it can repress inflammatory responses linked to chronic stress, e.g., in nutritional overload and during the aging process. AMPK can inhibit endoplasmic reticulum and oxidative stresses which are involved in metabolic disorders and the aging process. Interestingly, many target proteins of AMPK are so-called longevity factors, e.g., SIRT1, p53, and FoxOs, which not only can increase the stress resistance and extend the lifespan of many organisms but also inhibit the inflammatory responses. The activation capacity of AMPK declines in metabolic stress and with aging which could augment the metabolic diseases and accelerate the aging process. We will review the AMPK pathways involved in the inhibition of NF-κB signaling and suppression of inflammation. We also emphasize that the capacity of AMPK to repress inflammatory responses can have a significant impact on both healthspan and lifespan. BACKGROUND: Recent data suggest that insulin-like growth factor (IGF)-1 resistance in neurons prolongs longevity. In C. elegans this effect is mediated via DAF-16 the ortholog of the mammalian FoxO transcription factors. 3 different FoxO transcription factors (FoxOs) are expressed in rodent CNS: FoxO1, FoxO3a and FoxO6. METHODS: To define whether the different FoxOs are region-, sex- and age-specifically expressed, we analyzed FoxO mRNA levels in different brain regions from 6, 16, 60 and 100 weeks old mice using realtime-PCR. In addition, we fed mice a high fat diet (HFD) to experimentally induce obesity and diabetes and analyzed FoxO mRNA in the different brain regions. RESULTS: Interestingly, FoxO1 was predomitly expressed in the hippocampus whereas FoxO3a was quantitatively the most abundant FoxO in the neocortex. During aging, FoxO1 expression peaked in all brain regions at 16 weeks and FoxO6 showed its highest expression at 60 weeks in the parietal and occipital cortex. In 6 weeks old mice FoxO6 expression was higher in male compared to female mice in the hippocampus and all cortical regions. Surprisingly, in HFD animals FoxO3a was significantly less expressed in the cerebellum and all cortical regions compared to control animals. Even more dramatic, FoxO6 expression dropped about 80% in all brain regions in response to HFD. CONCLUSION: Thus, FoxOs in the CNS showed a highly distinct expression, which in addition was age- and sex-dependent. In contrast to FoxO1, FoxO3a and FoxO6 were specifically diminished in the CNS of HFD animals possibly contributing to the reduced lifespan observed in these animals. Forkhead box O (FOXO) transcription factors have a conserved function in regulating metazoan lifespan. A key function in this process involves the regulation of the cell cycle and stress responses including free radical scavenging. We employed yeast chronological and replicative lifespan assays, as well as oxidative stress assays, to explore the potential evolutionary conservation of function between the FOXOs and the yeast forkhead box transcription factors FKH1 and FKH2. We report that the deletion of both FKH genes impedes normal lifespan and stress resistance, particularly in stationary phase cells, which are non-responsive to caloric restriction. Conversely, increased expression of the FKHs leads to extended lifespan and improved stress response. Here we show the Anaphase-Promoting Complex (APC) genetically interacts with the Fkh pathway, likely working in a linear pathway under normal conditions, as fkh1Δ fkh2Δ post-mitotic survival is epistatic to that observed in apc5(CA) mutants. However, under stress conditions, post-mitotic survival is dramatically impaired in apc5(CA) fkh1Δ fkh2Δ, while increased expression of either FKH rescues APC mutant growth defects. This study establishes the FKHs role as evolutionarily conserved regulators of lifespan in yeast and identifies the APC as a novel component of this mechanism under certain conditions, likely through combined regulation of stress response, genomic stability, and cell cycle regulation.

Which antibody is implicated in the Bickerstaff's brainstem encephalitis?

The syndrome defined by Bickerstaff of progressive, external ophthalmoplegia and ataxia, with disturbance of consciousness or hyperreflexia, has subsequently been associated with antiganglioside antibody, anti-GQ1b

We presented a case of probable Bickerstaff's brainstem encephalitis. A 39-year-old woman developed easy falling, progressive consciousness disturbance, total ophthalmoplegia, and bilateral pyramida tract sign. In serum anti-ganglioside antibody assay using enzyme-linked immunosorbent assay, high anti-GQ1b antibody was found. Electroencephalography was dominated by alpha activity, superimposed with occasional theta wave bursts. Brain MRI showed abnormal signal hyperintensities in the tegmentum of the midbrain to the upper pons on T2 weighted images and swelling of the midbrain and pons on T1 weighted images. Five days after the onset of the disease, she had respiratory arrest, which necessitated artificial ventilation for a few days. Then, she began to recover. However, she gained only partial recovery, leaving upward gaze palsy, right abducens nerve palsy, pseudbulbar palsy and quadriplegia. Herpes simplex virus (HSV) is a rare, antecedent infectious agent in Guillain-Barré syndrome (GBS). We report a patient with overlapping GBS and Bickerstaff's brainstem encephalitis (BBE). The patient had a vesicular lesion on her nose. Antecedent HSV type 1 (HSV-1) infection was confirmed by isolation of the virus and detection of the presence of serum anti-HSV-1 IgM antibody during the acute phase. Her serum IgG had high anti-GQ1b antibody titer. External ophthalmoplegia has been noted in 2 of 4 reported cases of HSV-associated GBS. Herpetic brainstem encephalitis cases of poor prognosis are known, but only 2 cases of benign brainstem encephalitis secondary to HSV infection, in which there was acute ophthalmoplegia and clinical features consistent with those of BBE have been reported. The authors reported the neurological disease spectrum associated with autoantibodies against minor gangliosides GM1b and GalNAc-GD1a. IgG and IgM antibody reactivity against gangliosides GM1, GM2, GM1b, GD1a, GalNAc-GD1a and GQ1b was investigated in sera from 7000 consecutive patients who had various neurological conditions. The clinical diagnoses for 456 anti-GM1b-positive patients were Guillain-Barré syndrome (GBS, 71%), atypical GBS with preserved deep tendon reflexes (12%), Fisher syndrome (10%), Bickerstaff's brainstem encephalitis (2%), ataxic GBS (2%) and acute ophthalmoparesis (1%). For 193 anti-GalNAc-GD1a-positive patients, the diagnoses were GBS (70%), atypical GBS (16%), Fisher syndrome (10%) and Bickerstaff's brainstem encephalitis (3%). Of the patients with GBS or atypical GBS, 28% of 381 anti-GM1b-positive and 31% of 166 anti-GalNAc-GD1a-positive patients had neither anti-GM1 nor anti-GD1a antibodies. Of those patients with Fisher syndrome, Bickerstaff's brainstem encephalitis, ataxic GBS or acute ophthalmoparesis, 33% of 67 anti-GM1b-positive, and 52% of 25 anti-GalNAc-GD1a-positive patients had no anti-GQ1b antibodies. Autoantibodies against GM1b and GalNAc-GD1a are associated with GBS, Fisher syndrome and related conditions. These antibodies should provide useful serological markers for identifying patients who have atypical GBS with preserved deep tendon reflexes, ataxic GBS, Bickerstaff's brainstem encephalitis or acute ophthalmoparesis, especially for those who have no antibodies to GM1, GD1a or GQ1b. A method to prepare GM1b was developed. Bickerstaff brainstem encephalitis is a clinical syndrome of ophthalmoplegia, cerebellar ataxia, and central nervous system signs and is associated with the presence of anti-GQ1b antibodies. There is a clinical continuum between Bickerstaff brainstem encephalitis and Miller Fisher syndrome. We describe the case of an 11-year-old boy with encephalopathy, external ophthalmoplegia, brainstem signs, and ataxia with raised titers of anti-GQ1b antibodies. He presented following a respiratory illness and had laboratory evidence of recent infection with Mycoplasma pneumoniae. M pneumoniae infection has been associated with both Bickerstaff brainstem encephalitis and Miller Fisher syndrome. This is only the second case in the literature of Bickerstaff brainstem encephalitis with raised titers of anti-GQ1b antibodies described in association with M pneumoniae infection. The patient responded to intravenous immunoglobulin administration. Twenty-eight patients suffered Campylobacter jejuni enteritis after eating raw chicken. Among them, only one patient developed Bickerstaff's brainstem encephalitis, who carried anti-GQ1b IgG antibodies. In contrast, none of the others did the autoantibodies. C. jejuni was cultured from all stool samples from five patients with enteritis alone. All the isolates had the same genotype, cst-II (Asn51), which are characteristic of strains isolated from Bickerstaff's brainstem encephalitis. These findings suggest that host susceptibility may play a role in inducing the production of anti-ganglioside antibodies and the development of Bickerstaff's brainstem encephalitis. BACKGROUND: Anti-GQ1b antibody has been found in Miller Fisher syndrome (MFS), Guillain-Barré syndrome (GBS) with ophthalmoplegia, Bickerstaff brainstem encephalitis (BBE), and acute ophthalmoplegia without ataxia (AO). The aim of this study was to determine the clinical features of AO associated with anti-GQ1b antibody. METHODS: We retrospectively collected 34 patients with anti-GQ1b antibody syndrome. Of these patients, 31 patients had ophthalmoplegia. The patients with ophthalmoplegia were classified into MFS (n = 13), AO (n = 11), GBS with ophthalmoplegia (n = 6), and BBE (n = 1). We analyzed clinical features and patterns of external and internal ophthalmoplegia of AO, and neuro-ophthalmologic findings were compared with those of other anti-GQ1b syndromes with ophthalmoplegia. RESULTS: AO was observed in 11 (32.4%) of the 34 patients with anti-GQ1b antibody. External ophthalmoparesis was present in all the patients and included mixed horizontal-vertical (n = 7), pure horizontal (n = 3), and pure vertical gaze palsy (n = 1). Binocular involvement was common, but unilateral ophthalmoparesis was also observed in 27.3%. Other findings included ptosis (n = 5, 45.5%) and internal ophthalmoplegia (n = 6, 54.5%). Other anti-GQ1b antibody syndromes had prominent neurologic signs including ataxia, weakness, and facial palsy in addition to ophthalmoplegia. The patterns of neuro-ophthalmologic findings did not differ between AO and other anti-GQ1b antibody syndromes with ophthalmoplegia. CONCLUSIONS: Acute ophthalmoplegia (AO) commonly occurs in anti-GQ1b antibody syndrome and manifests as various combinations of external and internal ophthalmoplegia. Internal ophthalmoplegia is fairly common and unilateral involvement may occur in AO. The discovery of the association of the anti-GQ1b IgG antibody with the postinfectious clinical syndromes of ophthalmoplegia, ataxia, and areflexia helped house the phenotypes of the Miller Fisher syndrome (MFS), atypical MFS, Guillain-Barré syndrome with ophthalmoplegia, and Bickerstaff's brainstem encephalitis under one roof. The neuro-ophthalmologic signs classically predominate and may vary from case to case, but they maintain clinically recognizable patterns that assist with the diagnosis. The identification of a common lipopolysaccharide on the plasma membrane in human cranial and peripheral nerves at the GQ1b epitope and on infectious particles of bacteria and viruses (ie, Campylobacter jejuni) demonstrates molecular mimicry. The high frequency of oculomotor dysfunction is partially explained by the tissue ganglioside concentration and distribution and the attraction of antibody-stimulating complement activation. Current experimental treatment targets antibody removal and neutralization and prevents membrane attack complex formation through deactivation of complement. This article aims to bring together the historically disparate opinions on the origins of these syndromes as either a purely peripheral nervous system or central nervous system dysfunction, highlight the clinical neuro-ophthalmologic signs, discuss some of the biology of the anti-GQ1b antibody, and review imaging abnormalities and treatment of this fascinating disorder. Miller Fisher syndrome (MFS), a variant of the Guillain-Barré syndrome (GBS), is characterized by ophthalmoplegia, ataxia, and areflexia. The annual incidence is around one patient per one million population. The antiganglioside anti-GQ1b IgG antibody has a role in the pathogenesis of the syndrome, especially of ophthalmoplegia. The presence of this antibody in the serum can be identified in over 80% of the patients, peaking in the first week, whereas albuminocytological dissociation in the cerebrospinal fluid (CSF) appears later. The most consistent electrophysiological findings in MFS are reduced sensory nerve action potentials and absent H reflexes. More variability is seen with F waves and various investigations involving cranial structures. Although there are usually no abnormalities in MFS by routine neuroimaging, in a few cases, contrast enhancement of nerve roots and signs of central nervous system involvement were described supporting the hypothesis of an anti-GQ1b-syndrome, a continuum involving GBS, MFS, and Bickerstaff's brainstem encephalitis. Owing to the lack of randomized trials, treatments used for GBS (intravenous immunoglobulin and plasmapheresis) are usually applied, although from retrospective analyses, the outcome was similar between treated and untreated subjects. The outcome of MFS is usually good with case fatality of < 5%. In the few autopsy cases, macroscopic abnormalities were generally not seen in the nervous system. Microscopic examination of the peripheral nervous system (including cranial nerves) showed segmental demyelination with minimal perivascular infiltration with normal spinal cord and brain stem. BACKGROUND: Bickerstaff's brainstem encephalitis (BBE), together with Miller Fisher syndrome (MFS) and Guillain-Barré syndrome (GBS) were considered to form a continuous clinical spectrum. An anti-GQ1b antibody syndrome has been proposed to underlie the common pathophysiology for the three disorders; however, other studies have found a positive anti-GM1 instead of anti-GQ1b antibody. CASE PRESENTATION: Here we report a 20-year-old male patient with overlapping BBE, MFS and GBS. The patient had a positive family history of bronchial asthma and had suffered from the condition for over 15 years. He developed BBE symptoms nine days after an asthma exacerbation. During the course of illness, he had significantly elevated IgE levels in both serum and cerebrospinal fluid. Serologic analysis of antibodies against ganglioside complexes (anti-GDIa, anti-GDIb, anti-GM1, anti-GM2, anti-GM3, anti-GQIb and anti-GTIb antibodies) showed negative results. CONCLUSIONS: Since asthma has recently been related to autoimmune disease, our case supports an autoimmune mechanism underlying the clinical spectrum composed of BBE, MFS and GBS. However, contrary to a proposed anti-GQ1b antibody syndrome, we would suggest that pathogenesis of this clinical spectrum is not limited to anti-ganglioside antibodies. In the 1950s, Bickerstaff and Fisher independently described cases with a unique presentation of ophthalmoplegia and ataxia. The neurological features were typically preceded by an antecedent infection and the majority of patients made a spontaneous recovery. In the cases with Bickerstaff brainstem encephalitis, there was associated altered consciousness and in some, hyperreflexia, in support of a central pathology whereas in Fisher syndrome, patients were areflexic in keeping with a peripheral aetiology. However, both authors recognised certain similarities to Guillain-Barré syndrome such as the presence of peripheral neuropathy and cerebrospinal fluid albuminocytological dissociation. The discovery of immunoglobulin G anti-GQ1b antibodies in patients with Fisher syndrome and later in Bickerstaff brainstem encephalitis was crucial in providing the necessary evidence to conclude that both conditions were in fact part of the same spectrum of disease by virtue of their common clinical and immunological profiles. Following this, other neurological presentations that share anti-GQ1b antibodies emerged in the literature. These include acute ophthalmoparesis and acute ataxic neuropathy, which represent the less extensive spectrum of the disease whereas pharyngeal-cervical-brachial weakness and Fisher syndrome overlap with Guillain-Barré syndrome represent the more extensive end of the spectrum. The conditions can be referred to as the 'anti-GQ1b antibody syndrome'. In this review, we look back at the historical descriptions and describe how our understanding of Fisher syndrome and Bickerstaff brainstem encephalitis has evolved from their initial descriptions more than half a century ago. We report a 72-year-old woman with overlapping Miller Fisher syndrome (MFS), Guillain-Barré syndrome (GBS) and Bickerstaff's brainstem encephalitis (BBE). She developed diplopia and unsteady gait a week after an upper respiratory infection on day 1. She had weakness of both upper limbs on day 3 and became drowsy, and her respiratory status worsened on day 5. Neurologic examination revealed ophthalmoplegia, ataxia, symmetrical weakness, areflexia, and consciousness disturbance. We diagnosed her with MFS on day 1, GBS on day 3 and overlapping BBE on day 5. She underwent immunoadsorption therapy and two courses of intravenous immunoglobulin therapy. Ten months after onset, her symptoms had fully recovered. Anti-GM1 IgG, GD1a IgG, GQ1b IgG, and GT1a IgG antibodies were positive. Our case supports the notion that MFS, GBS, and BBE are all part of a continuous clinical spectrum, which is an antibody-mediated process. Edwin Bickerstaff and Philip Cloake reported in the 1950's three cases of reversible encephalitis. The concept of antibody associated encephalitis had not been proposed at the time they astutely recognized the importance of disease pattern recognition and postulated a potential immune based mechanism. The syndrome defined by Bickerstaff of progressive, external ophthalmoplegia and ataxia, with disturbance of consciousness or hyperreflexia, has subsequently been associated with anti-GQ1b antibodies. Interestingly one of the three original cases, a young woman who developed seizures, an eye movement disorder and acute psychosis while awaiting ovarian cystectomy, has features that may be more consistent with anti-NMDA receptor encephalitis. This is the case of a 79-year-old man with chronic lymphocytic leukemia who presented with Guillain-Barré syndrome with features overlapping with the Miller Fisher syndrome and Bickerstaff brainstem encephalitis and positive antiganglioside GQ1b antibody about 6 months after treatment with bendamustine and rituximab. His clinical and neurologic condition continued to deteriorate despite sequential treatment with corticosteroids, intravenous immunoglobulin and plasmapheresis, but in the end, he had a complete and durable response to treatment with alemtuzumab. A flaccid tetraparesis in Bickerstaff's brainstem encephalitis (BBE) is presumed to be a sign of overlapping Guillain-Barré syndrome (GBS). In addition, BBE and Fisher syndrome, which are clinically similar and are both associated with the presence of the immunoglobulin G anti-GQ1b antibody, represent a specific autoimmune disease with a wide spectrum of symptoms that include ophthalmoplegia and ataxia. A 2-year-old boy presented with rapidly progressive ophthalmoplegia, ataxia, hyporeflexia, weakness of the lower extremities, and, subsequently, disturbance of consciousness. He experienced bronchitis with watery diarrhea and had laboratory evidence of recent infection with Epstein-Barr virus (EBV). He was diagnosed as having overlapping GBS and BBE associated with EBV and received treatment with a combination of immunoglobulin and methylprednisolone, as well as acyclovir, and had recovered completely after 3 months. In addition, he has not experienced any relapse over the past year. We suggest that combinations of symptoms and signs of central lesions (disturbance of consciousness) and peripheral lesions (ophthalmoplegia, facial weakness, limb weakness, and areflexia) are supportive of a diagnosis of overlapping GBS and BBE and can be helpful in achieving an early diagnosis, as well as for the administration of appropriate treatments.

Which micro-RNAs have been associated in the pathogenesis of Rheumatoid Arthritis?

Different expression patterns of mir-146a, miRNA-155, miRNA-124a, mir-203, mir-223, mir-346, mir-132, mir-363, mir-498, mir-15a, and mir-16 were documented in several tissue sample types of RA patients.

OBJECTIVE: MicroRNAs (miRNA) have recently emerged as a new class of modulators of gene expression. In this study we investigated the expression, regulation, and function of miR-155 and miR-146a in rheumatoid arthritis (RA) synovial fibroblasts (RASFs) and RA synovial tissue. METHODS: Locked nucleic acid microarray was used to screen for differentially expressed miRNA in RASFs treated with tumor necrosis factor alpha (TNFalpha). TaqMan-based real-time polymerase chain reaction was applied to measure the levels of miR-155 and miR-146a. Enforced overexpression of miR-155 was used to investigate the function of miR-155 in RASFs. RESULTS: Microarray analysis of miRNA expressed in RASFs treated with TNFalpha revealed a prominent up-regulation of miR-155. Constitutive expression of both miR-155 and miR-146a was higher in RASFs than in those from patients with osteoarthritis (OA), and expression of miR-155 could be further induced by TNFalpha, interleukin-1beta, lipopolysaccharide, poly(I-C), and bacterial lipoprotein. The expression of miR-155 in RA synovial tissue was higher than in OA synovial tissue. Enforced expression of miR-155 in RASFs was found to repress the levels of matrix metalloproteinase 3 (MMP-3) and reduce the induction of MMPs 3 and 1 by Toll-like receptor ligands and cytokines. Moreover, compared with monocytes from RA peripheral blood, RA synovial fluid monocytes displayed higher levels of miR-155. CONCLUSION: This study provides the first description of increased expression of miRNA miR-155 and miR-146a in RA. Based on these findings, we postulate that the inflammatory milieu may alter miRNA expression profiles in resident cells of the rheumatoid joints. Considering the repressive effect of miR-155 on the expression of MMPs 3 and 1 in RASFs, we hypothesize that miR-155 may be involved in modulation of the destructive properties of RASFs. OBJECTIVE: Several microRNA, which are approximately 22-nucleotide noncoding RNAs, exhibit tissue-specific or developmental stage-specific expression patterns and are associated with human diseases. The objective of this study was to identify the expression pattern of microRNA-146 (miR-146) in synovial tissue from patients with rheumatoid arthritis (RA). METHODS: The expression of miR-146 in synovial tissue from 5 patients with RA, 5 patients with osteoarthritis (OA), and 1 normal subject was analyzed by quantitative reverse transcription-polymerase chain reaction (RT-PCR) and by in situ hybridization and immunohistochemistry of tissue sections. Induction of miR-146 following stimulation with tumor necrosis factor alpha (TNFalpha) and interleukin-1beta (IL-1beta) of cultures of human rheumatoid arthritis synovial fibroblasts (RASFs) was examined by quantitative PCR and RT-PCR. RESULTS: Mature miR-146a and primary miR-146a/b were highly expressed in RA synovial tissue, which also expressed TNFalpha, but the 2 microRNA were less highly expressed in OA and normal synovial tissue. In situ hybridization showed primary miR-146a expression in cells of the superficial and sublining layers in synovial tissue from RA patients. Cells positive for miR-146a were primarily CD68+ macrophages, but included several CD3+ T cell subsets and CD79a+ B cells. Expression of miR-146a/b was markedly up-regulated in RASFs after stimulation with TNFalpha and IL-1beta. CONCLUSION: This study shows that miR-146 is expressed in RA synovial tissue and that its expression is induced by stimulation with TNFalpha and IL-1beta. Further studies are required to elucidate the function of miR-146 in these tissues. INTRODUCTION: MicroRNAs are small noncoding RNA molecules that negatively regulate gene expression via degradation or translational repression of their targeted mRNAs. It is known that aberrant microRNA expression can play important roles in cancer, but the role of microRNAs in autoimmune diseases is only beginning to emerge. In this study, the expression of selected microRNAs is examined in rheumatoid arthritis. METHODS: Total RNA was isolated from peripheral blood mononuclear cells obtained from patients with rheumatoid arthritis, and healthy and disease control individuals, and the expression of miR-146a, miR-155, miR-132, miR-16, and microRNA let-7a was analyzed using quantitative real-time PCR. RESULTS: Rheumatoid arthritis peripheral blood mononuclear cells exhibited between 1.8-fold and 2.6-fold increases in miR-146a, miR-155, miR-132, and miR-16 expression, whereas let-7a expression was not significantly different compared with healthy control individuals. In addition, two targets of miR-146a, namely tumor necrosis factor receptor-associated factor 6 (TRAF6) and IL-1 receptor-associated kinase 1 (IRAK-1), were similarly expressed between rheumatoid arthritis patients and control individuals, despite increased expression of miR-146a in patients with rheumatoid arthritis. Repression of TRAF6 and/or IRAK-1 in THP-1 cells resulted in up to an 86% reduction in tumor necrosis factor-alpha production, implicating that normal miR-146a function is critical for the regulation of tumor necrosis factor-alpha production. CONCLUSIONS: Recent studies have shown that synovial tissue and synovial fibroblasts from patients with rheumatoid arthritis exhibit increased expression of certain microRNAs. Our data thus demonstrate that microRNA expression in rheumatoid arthritis peripheral blood mononuclear cells mimics that of synovial tissue/fibroblasts. The increased microRNA expression in rheumatoid arthritis patients is potentially useful as a marker for disease diagnosis, progression, or treatment efficacy, but this will require confirmation using a large and well defined cohort. Our data also suggest a possible mechanism contributing to rheumatoid arthritis pathogenesis, whereby miR-146a expression is increased but unable to properly function, leading to prolonged tumor necrosis factor-alpha production in patients with rheumatoid arthritis. OBJECTIVE: To elucidate the role of microRNA (miRNA) in the pathogenesis of rheumatoid arthritis (RA), we analyzed synoviocytes from RA patients for their miRNA expression. METHODS: Synoviocytes derived from surgical specimens obtained from RA patients were compared with those obtained from osteoarthritis (OA) patients for their expression of a panel of 156 miRNA with quantitative stem-loop reverse transcription-polymerase chain reaction. The miRNA whose expression decreased or increased in RA synoviocytes as compared with OA synoviocytes were identified, and their target genes were predicted by computer analysis. We used an in vitro system of enhancing the expression of specific miRNA by transfection of precursors into synoviocytes, and then we performed proliferation, cell cycle, and apoptosis assays, as well as enzyme-linked immunosorbent assays for cytokine production. The effects of transfection on predicted target protein and messenger RNA (mRNA) were then examined by Western blot analysis and luciferase reporter assay. RESULTS: We found that miR-124a levels significantly decreased in RA synoviocytes as compared with OA synoviocytes. Transfection of precursor miR-124a into RA synoviocytes significantly suppressed their proliferation and arrested the cell cycle at the G1 phase. We identified a putative consensus site for miR-124a binding in the 3'-untranslated region of cyclin-dependent kinase 2 (CDK-2) and monocyte chemoattractant protein 1 (MCP-1) mRNA. Induction of miR-124a in RA synoviocytes significantly suppressed the production of the CDK-2 and MCP-1 proteins. Luciferase reporter assay demonstrated that miR-124a specifically suppressed the reporter activity driven by the 3'-untranslated regions of CDK-2 and MCP-1 mRNA. CONCLUSION: The results of this study suggest that miR-124a is a key miRNA in the posttranscriptional regulatory mechanisms of RA synoviocytes. miRNAs have recently emerged as key regulators of the immune system, being involved in lymphocyte selection and proliferation, in T(reg) cells differentiation, and in hematopoiesis in general. Rheumatoid arthritis (RA) is an autoimmune pathology the etiology of which is still obscure. Although a multifactorial pathogenesis has been hypothesized, the precise mechanisms leading to the disease are still poorly understood at the molecular level. miRNA expression profile analysis highlighted that miR-223 is the only miRNA that is strikingly deregulated in peripheral T-lymphocytes from RA patients compared with healthy donors. Further analysis by quantitative reverse transcription-polymerase chain analysis confirmed that miR-223 is overexpressed in T-lymphocytes from RA patients (n = 28) compared with healthy donors (n = 10). Moreover, purification of different T-lymphocyte populations from RA patients highlights that miR-223 is expressed at higher levels in naive CD4(+) lymphocytes, whereas its expression is barely detectable in T(h)-17 cells. In summary, our data provide a first characterization of the miRNA expression profiles of peripheral T-lymphocytes of RA patients, identifying miR-223 as overexpressed in CD4(+) naive T-lymphocytes from these individuals. A deeper analysis of the biologic functions and effects of the expression of miR-223 in T-lymphocytes is needed to clarify the exact link between our observation and the disease. MicroRNAs (miRNAs) represent a class of non-coding RNA molecules playing pivotal roles in cellular and developmental processes. miRNAs modulate the expression of multiple target genes at the post-transcriptional level and are predicted to affect up to one-third of all human protein-encoding genes. Recently, miRNA involvement in the adaptive and innate immune systems has been recognized. Rheumatoid arthritis serves an example of a chronic inflammatory disorder in which miRNAs modulate the inflammatory process in the joints, with the potential to serve as biomarkers for both the inflammatory process and the potential for therapeutic response. This review discusses the investigations that led to miRNA discovery, miRNA biogenesis and mode of action, and the diverse roles of miRNAs in modulating the immune and inflammatory responses. We conclude with a discussion of the implications of miRNA biology in rheumatoid arthritis and other autoimmune disorders. INTRODUCTION: Increasing evidence indicates that microRNAs (miRNAs) play a critical role in the pathogenesis of inflammatory diseases. The aim of the study was to investigate the expression pattern and function of miRNAs in CD4+ T cells from patients with rheumatoid arthritis (RA). METHODS: The expression profile of miRNAs in CD4+ T cells from synovial fluid (SF) and peripheral blood of 33 RA patients was determined by microarray assay and validated by qRT-PCR analysis. The correlation between altered expression of miRNAs and cytokine levels was determined by linear regression analysis. The role of miR-146a overexpression in regulating T cell apoptosis was evaluated by flow cytometry. A genome-wide gene expression analysis was further performed to identify miR-146a-regulated genes in T cells. RESULTS: miRNA expression profile analysis revealed that miR-146a expression was significantly upregulated while miR-363 and miR-498 were downregulated in CD4+ T cells of RA patients. The level of miR-146a expression was positively correlated with levels of tumor necrosis factor-alpha (TNF-alpha), and in vitro studies showed TNF-alpha upregulated miR-146a expression in T cells. Moreover, miR-146a overexpression was found to suppress Jurkat T cell apoptosis. Finally, transcriptome analysis of miR-146a overexpression in T cells identified Fas associated factor 1 (FAF1) as a miR-146a-regulated gene, which was critically involved in modulating T cell apoptosis. CONCLUSIONS: We have detected increased miR-146a in CD4+ T cells of RA patients and its close correlation with TNF-alpha levels. Our findings that miR-146a overexpression suppresses T cell apoptosis indicate a role of miR-146a in RA pathogenesis and provide potential novel therapeutic targets. BACKGROUND: Interleukin (IL)-17 is an important factor in rheumatoid arthritis (RA) pathogenesis. MicroRNA (miRNA)s are a family of non coding RNAs and associated with human diseases including RA. The purpose of this study is to identify the miRNAs in the differentiation of IL-17 producing cells, and analyze their expression pattern in the peripheral blood mononuclear cells (PBMC) and synovium from RA patients. METHODS: IL-17 producing cells were expanded from CD4+T cell. MiRNA microarray was performed to identify the miRNAs in the differentiation of IL-17 producing cells. Quantitative polymerase chain reaction was performed to examine the expression patterns of the identified miRNAs in the PBMC and synovium from RA and osteoarthritis (OA) patients. Double staining combining in situ hybridization and immunohistochemistry of IL-17 was performed to analyze the expression pattern of identified miRNA in the synovium. RESULTS: Six miRNAs, let-7a, miR-26, miR-146a/b, miR-150, and miR-155 were significantly up regulated in the IL-17 producing T cells. The expression of miR-146a and IL-17 was higher than in PBMC in the patients with low score of Larsen grade and short disease duration. MiR-146a intensely expressed in RA synovium in comparison to OA. MiR-146a expressed intensely in the synovium with hyperplasia and high expression of IL-17 from the patients with high disease activity. Double staining revealed that miR-146a expressed in IL-17 expressing cells. CONCLUSION: These results indicated that miR-146a was associated with IL-17 expression in the PBMC and synovium in RA patients. There is the possibility that miR-146a participates in the IL-17 expression. MicroRNAs (miRNAs) are small noncoding RNA molecules that negatively regulate gene expression at the post-transcriptional level. Currently, there are 939 mature human miRNA sequences listed in the Sanger updated miRNA registry. There are approximately 1500 predicted miRNAs in the human genome that may regulate the expression of one third of our genes. By controlling the accumulation of the target protein(s) in cells, these regulatory RNA molecules participate in key functions in many physiological networks and their deregulation has been implicated in the pathogenesis of serious human disorders, such as cancer and infection. The implication of miRNAs in immune-mediated disorders such as rheumatoid arthritis (RA) has recently emerged suggesting that miRNA-based therapeutic approaches may have a promising potential in these diseases. Here, we provide an overview of the state-of-the-art on miRNAs in RA, focusing on both systemic and local features of the pathology. OBJECTIVES: Rheumatoid arthritis (RA) is a chronic inflammatory disorder with many genetic factors predisposing to disease susceptibility. MicroRNAs are a new discovered class of molecules that participate in post-transcriptional regulation of genes' expression. MicroRNA-146a was found to be increased in synovial fibroblasts, synovial tissue and PBMC from patients with RA. The aim of the present study was to reveal if there is any association of miRNA-146a variant rs2910164 and the two interleukin (IL) 1 receptor associated kinase (IRAK1, a target gene of mir-146a) polymorphisms rs3027898 and rs1059703 with RA predisposition. METHODS: One hundred and thirty-six RA patients and 147 controls were enrolled in the study. RESULTS: Strong statistically significant difference was observed in IRAK1 rs3027898 A > C polymorphism distribution between RA patients and controls (p = 0.044), which was higher comparing the distribution of allele A vs. allele C between the studied groups (p = 0.017). CONCLUSION: This is the first study that addresses association of a variant in a target of miR-146a, IRAK1 gene, with RA susceptibility. Further studies in other ethnic groups of patients could help to understand the extent of the proposed association. OBJECTIVE: MicroRNA (miRNA) are recognized as important regulators of a variety of fundamental biologic processes. Previously, we described increased expression of miR-155 and miR-146a in rheumatoid arthritis (RA) and showed a repressive effect of miR-155 on matrix metalloproteinase (MMP) expression in RA synovial fibroblasts (RASFs). The present study was undertaken to examine alterations in expression of miR-203 in RASFs and analyze its role in fibroblast activation. METHODS: Differentially expressed miRNA in RASFs versus osteoarthritis synovial fibroblasts (OASFs) were identified by real-time polymerase chain reaction (PCR)-based screening of 260 individual miRNA. Transfection of miR-203 precursor was used to analyze the function of miR-203 in RASFs. Levels of interleukin-6 (IL-6) and MMPs were measured by real-time PCR and enzyme-linked immunosorbent assay. RASFs were stimulated with IL-1β, tumor necrosis factor α (TNFα), lipopolysaccharide (LPS), and 5-azacytidine (5-azaC). Activity of IκB kinase 2 was inhibited with SC-514. RESULTS: Expression of miR-203 was higher in RASFs than in OASFs or fibroblasts from healthy donors. Levels of miR-203 did not change upon stimulation with IL-1β, TNFα, or LPS; however, DNA demethylation with 5-azaC increased the expression of miR-203. Enforced expression of miR-203 led to significantly increased levels of MMP-1 and IL-6. Induction of IL-6 by miR-203 overexpression was inhibited by blocking of the NF-κB pathway. Basal expression levels of IL-6 correlated with basal expression levels of miR-203. CONCLUSION: The current results demonstrate methylation-dependent regulation of miR-203 expression in RASFs. Importantly, they also show that elevated levels of miR-203 lead to increased secretion of MMP-1 and IL-6 via the NF-κB pathway and thereby contribute to the activated phenotype of synovial fibroblasts in RA. Biomarkers are indicators of biological conditions that can be detected and measured in body fluids or tissues. Biomarkers can be detectable before the clinical onset of the disease, and are thus useful for prognosis; they can be measured at early stages of the disease and are useful for stratification and classification of the disease and patients; they can be monitored along the disease course and used as indicators of risk factors and pharmacological response to treatment. Ideally, biomarkers should be sensitive, specific, have high predictive power, and be easily accessible. Rheumatoid arthritis (RA) is the most frequent chronic inflammatory disorder, affecting millions of people worldwide and leading to joint damage and substantial morbidity. RA is a heterogeneous disorder with a fluctuating clinical course and unpredictable prognosis. And although a large panel of biologics is available to clinicians, the main challenge remains to treat patients as early as possible with the most personalised therapy. Today, the most challenging issue in RA is the identification of biomarkers for early disease diagnosis and for prediction of drug response. Among molecules that can fulfil this expectation, micro(mi)-RNAs certainly represent an option. The potential value of miRNAs as a novel class of biomarkers is well documented in cancer. Moreover, the presence and stability of miRNAs in body fluids provide fingerprints that can serve as molecular biomarkers for disease diagnosis and therapeutic outcome. As a growing body of evidences reveals abnormal expression of specific miRNAs in RA tissues, the use of a blood-based miRNA signature for optimal diagnosis and treatment becomes a realistic option. The epigenetic mechanisms in regulation of genes' expression seem to be another field of research that gains land in genetic association studies of rheumatoid arthritis (RA) susceptibility factors. Recently, a new class of molecules has been discovered, the microRNAs (miRNAs). miRNAs are related to post-transcriptional regulation of genes' expression. Different expression patterns of mir-146a, miRNA-155, miRNA-124a, mir-203, mir-223, mir-346, mir-132, mir-363, mir-498, mir-15a, and mir-16 were documented in several tissue sample types of RA patients. The polymorphisms of these miRNAs and their gene targets, which previously have been associated with RA or other autoimmune diseases, are also reviewed. Finally, using web-based tools we propose polymorphisms of the discussed miRNAs and their gene-targets that worth to be studied for their role in RA predisposition. OBJECTIVE: To investigate the expression and effect of the microRNA-34 (miR-34) family on apoptosis in rheumatoid arthritis synovial fibroblasts (RASFs). METHODS: Expression of the miR-34 family in synovial fibroblasts with or without stimulation with Toll-like receptor (TLR) ligands, tumor necrosis factor α (TNFα), interleukin-1β (IL-1β), hypoxia, or 5-azacytidine was analyzed by real-time polymerase chain reaction (PCR). Promoter methylation was studied by combined bisulfite restriction analysis. The effects of overexpression and silencing of miR-34a and miR-34a* on apoptosis were analyzed by annexin V/propidium iodide staining. Production of X-linked inhibitor of apoptosis protein (XIAP) was assessed by real-time PCR and immunohistochemistry analysis. Reporter gene assay was used to study the signaling pathways of miR-34a*. RESULTS: Basal expression levels of miR-34a* were found to be reduced in synovial fibroblasts from RA patients compared to osteoarthritis patients, whereas levels of miR-34a, miR-34b/b*, and miR-34c/c* did not differ. Neither TNFα, IL-1β, TLR ligands, nor hypoxia altered miR-34a* expression. However, we demonstrated that the promoter of miR-34a/34a* was methylated and showed that transcription of the miR-34a duplex was induced upon treatment with demethylating agents. Enforced expression of miR-34a* led to an increased rate of FasL- and TRAIL-mediated apoptosis in RASFs. Moreover, levels of miR-34a* were highly correlated with expression of XIAP, which was found to be up-regulated in RA synovial cells. Finally, we identified XIAP as a direct target of miR-34a*. CONCLUSION: Our data provide evidence of a methylation-specific down-regulation of proapoptotic miR-34a* in RASFs. Decreased expression of miR- 34a* results in up-regulation of its direct target XIAP, thereby contributing to resistance of RASFs to apoptosis. Rheumatoid arthritis (RA) is a systemic, inflammatory, autoimmune disorder with progressive articular damage that may result in lifelong disability. Although major strides in understanding the disease have been made, the pathogenesis of RA has not yet been fully elucidated. Early treatment can prevent severe disability and lead to remarkable patient benefits, although a lack of therapeutic efficiency in a considerable number of patients remains problematic. MicroRNAs (miRNAs) are small, non-coding RNAs that, depending upon base pairing to messenger RNA (mRNA), mediate mRNA cleavage, translational repression or mRNA destabilization. As fine tuning regulators of gene expression, miRNAs are involved in crucial cellular processes and their dysregulation has been described in many cell types in different diseases. In body fluids, miRNAs are present in microvesicles or incorporated into complexes with Argonaute 2 (Ago2) or high-density lipoproteins and show high stability. Therefore, they are of interest as potential biomarkers of disease in daily diagnostic applications. Targeting miRNAs by gain or loss of function approaches have brought therapeutic effects in various animal models. Over the past several years it has become clear that alterations exist in the expression of miRNAs in patients with RA. Increasing numbers of studies have shown that dysregulation of miRNAs in peripheral blood mononuclear cells or isolated T lymphocytes, in synovial tissue and synovial fibroblasts that are considered key effector cells in joint destruction, contributes to inflammation, degradation of extracellular matrix and invasive behaviour of resident cells. Thereby, miRNAs maintain the pathophysiological process typical of RA. The aim of the current review is to discuss the available evidence linking the expression of miRNAs to inflammatory and immune response in RA and their potential as biomarkers and the novel targets for treatment in patients with RA. OBJECTIVE: To identify novel microRNA (miR) associations in synovial fibroblasts (SF), by performing miR expression profiling on cells isolated from the human tumour necrosis factor (TNF) transgenic mouse model (TghuTNF, Tg197) and patients biopsies. METHODS: miR expression in SF from TghuTNF and wild-type (WT) control mice were determined by miR deep sequencing (miR-seq) and the arthritic profile was established by pairwise comparisons. Quantitative PCR analysis was utilised for profile validation, miR and gene quantitation in patient SF. Dysregulated miR target genes and pathways were predicted via bioinformatic algorithms and validated using gain-of-function coupled with reporter assay experiments. RESULTS: miR-seq demonstrated that TghuTNF-SF exhibit a distinct pathogenic profile with 22 significantly upregulated and 30 significantly downregulated miR. Validation assays confirmed the dysregulation of miR-223, miR-146a and miR-155 previously associated with human rheumatoid arthritis (RA) pathology, as well as that of miR-221/222 and miR-323-3p. Notably, the latter were also found significantly upregulated in patient RA SF, suggesting for the first time their association with RA pathology. Bioinformatic analysis suggested Wnt/cadherin signalling as a putative pathway target. miR-323-3p overexpression was shown to enhance Wnt pathway activation and decrease the levels of its predicted target β-transducin repeat containing, an inhibitor of β-catenin. CONCLUSIONS: Using miR-seq-based profiling in SF from the TghuTNF mouse model and validations in RA patient biopsies, the authors identified miR-221/222 and miR-323-3p as novel dysregulated miR in RA SF. Furthermore, the authors show that miR-323-3p is a positive regulator of WNT/cadherin signalling in RA SF suggesting its potential pathogenic involvement and future use as a therapeutic target in RA. Extensive research has shown that aberrant expression of microRNAs (miRNAs) plays an important role in innate and adaptive immune responses. The rs2910164 polymorphism has been identified as a functional variant, which affects the transcription and expression level of miR-146a and, thereby, contributes to the pathogenesis of several inflammatory and autoimmune diseases. To investigate whether the rs2910164 G/C polymorphism was associated with asthma, systemic lupus erythematosus (SLE) or juvenile rheumatoid arthritis (JRA), we performed an association study in a pediatric Mexican cohort. We included 979 pediatric patients (asthma: 402, SLE: 367 and JRA: 210) and 531 control subjects without inflammatory or immune diseases. Genotyping was performed using the 5' exonuclease technique. The genotype distribution of the rs2910164 polymorphism was in Hardy-Weinberg equilibrium in each group. No significant differences were detected in the distribution of this polymorphism between cases and controls (P = 0.108, 0.609 and 0.553 for subjects with asthma, JRA and SLE, respectively). However, stratification by gender showed a statistically significant difference between asthmatic and control females, where the C allele was significantly associated with protection to asthma (odds ratio = 0.694, 95% confidence interval 0.519-0.929, P = 0.0138). Our results provide evidence that rs2910164 may play a role in the susceptibility to childhood-onset asthma, but not SLE or JRA in Mexicans. Further association studies may contribute to determining the role of miR-146a single-nucleotide polymorphisms in immune-mediated diseases. Single nucleotide polymorphisms in pre‑microRNA (miRNA) may alter miRNA expression levels or processing and contribute to susceptibility in a wide range of diseases. The present study aimed to evaluate the possible association between rs2910164 and rs3746444 of the pre-miRNA (hsa-mir-146a and hsa-mir-499) polymorphisms and susceptibility to rheumatoid arthritis (RA) in an Iranian population. This case-control study was performed on 104 patients with RA and 110 healthy individuals. Tetra amplification refractory mutation system-polymerase chain reaction was used to genotype the hsa-mir-499 rs3746444 and hsa-mir-146a rs2910164 polymorphisms. The hsa-mir-499 rs3746444 polymorphism was a risk factor for predisposition to RA in codomit [TT vs. TC: odds ratio (OR), 2.11; 95% confidence interval (CI), 1.08-4.11; p=0.029; TT vs. CC: OR, 3.88; 95% CI, 1.68-8.98; p=0.002], domit (TT vs. TC-CC: OR, 2.64; 95% CI, 1.48-4.72; p=0.001) and recessive (TC-CC vs. CC: OR, 3.05; 95% CI, 1.36-6.83; p=0.007) tested inheritance models. In addition, the rs3746444 C allele was a risk factor for RA (OR, 2.49; 95% CI, 1.63-3.81; p<0.0001). No significant difference was found between the groups concerning the rs2910164 polymorphism (χ2=0.348, p=0.841). Our findings demonstrated that the hsa-mir-499 rs3746444, but not mir-146a rs2910164, polymorphism is associated with an increased RA risk in a sample of the Iranian population. Larger studies with different ethnicities are required to validate our findings. OBJECTIVE: To elucidate whether the microRNA (miRNA) cluster miR-17-92 contributes to the activated phenotype of rheumatoid arthritis synovial fibroblasts (RASFs). METHODS: RASFs were stimulated with tumor necrosis factor α (TNFα), and the expression and regulation of the miR-17-92 cluster were studied using real-time quantitative PCR (PCR) and promoter activity assays. RASFs were transfected with single precursor molecules of miRNAs from miR-17-92 and the expression of matrix-degrading enzymes and cytokines was measured by quantitative PCR and enzyme-linked immunosorbent assay. Potential miRNA targets were identified by computational prediction and were validated using reporter gene assays and Western blotting. The activity of NF-κB signaling was determined by reporter gene assays. RESULTS: We found that TNFα induces the expression of miR-17-92 in RASFs in an NF-κB-dependent manner. Transfection of RASFs with precursor molecules of single members of miR-17-92 revealed significantly increased expression levels of matrix-degrading enzymes, proinflammatory cytokines, and chemokines in precursor miR-18a (pre-miR-18a)-transfected RASFs. Using reporter gene assays, we identified the NF-κB pathway inhibitor TNFα-induced protein 3 as a new target of miR-18a. In addition, pre-miR-18a-transfected RASFs showed stronger activation of NF-κB signaling, both constitutively and in response to TNFα stimulation. CONCLUSION: Our data suggest that the miR-17-92-derived miR-18a contributes to cartilage destruction and chronic inflammation in the joint through a positive feedback loop in NF-κB signaling, with concomitant up-regulation of matrix-degrading enzymes and mediators of inflammation in RASFs. Rheumatoid arthritis (RA) is a symmetrical polyarticular disease of unknown aetiology that affects primarily the articular cartilage and bone. Characteristic features of RA pathogenesis are persistent inflammation, synovium hyperplasia and cartilage erosion accompanied by joint swelling and joint destruction. Several lines of evidence have showed a crucial role of activated fibroblast-like synoviocytes (FLS) in the pathogenesis of RA. MicroRNAs (miRNAs) are endogenous, single-stranded, non-coding RNAs with about 21 nucleotides in length and have been detected in a variety of sources, including tissues, serum, and other body fluids, such as saliva. In light of key roles of miRNAs in the regulation of gene expression, miRNAs influence a wide range of physiological and pathological processes. For example, miRNAs are evident in various maligt and nonmaligt diseases, and accumulating evidence also shows that miRNAs have important roles in the pathogenesis of RA. It has been demonstrated that miRNAs can be aberrantly expressed even in the different stages of RA progression, allowing miRNAs to help understand the pathogenesis of the disease, to act as important biomarkers, and to monitor the disease severity and the effects of drug treatment. In addition, miRNAs are emerging as potential targets for new therapeutic strategies of this kind of autoimmune disorders. The ultimate goal is the identification of miRNA targets that could be manipulated through specific therapies, aiming at activation or inhibition of specific miRNAs responsible for the RA development. In this review, the importance of miRNAs in the pathogenesis of RA is discussed systematically, with particular emphasis on the role of the crosstalk between DNA methylation and the microRNA machinery. Recently, various micro(mi)RNAs have been found deregulated in the setting of rheumatoid arthritis (RA), but their role in the pathogenesis of this disease remains a matter of debate. In the meanwhile, increasing evidence indicates a defective function of regulatory T cells (Tregs) in RA. This review discusses relevant studies addressing the function of Tregs and Cytotoxic T-Lymphocyte Antigen 4 in RA, provides recent data on the role of miRNAs for Tregs homeostasis, and focuses on the role of miR-155 in Tregs. In a final perspective section we discuss the potential impact of therapeutic miR-155 modulation in RA. Elevated expression of specific microRNAs (miRNA) in peripheral blood-derived mononuclear cells (PBMC), particularly miR-146a and miR-155, is associated with rheumatoid arthritis (RA). Whole blood has not been explored as a potential clinical material for monitoring the expression of miRNAs in RA. We sought to determine whether miRNA levels detected in whole blood samples correlated with those detected in simultaneously isolated peripheral blood-derived mononuclear cells (PBMC) from the same individuals, thus establishing the feasibility of using whole blood as a viable clinical material for monitoring miRNA expression in RA and other disorders. We demonstrated a highly significant linear correlation between miR-146a and miR-155 expression in PBMC and whole blood, from both healthy individuals and RA patients. Whole blood samples accurately reflect miRNA levels in PBMC and would be useful in monitoring the expression of miRNAs as biomarkers. The detection of miRNA levels in samples that are readily obtained in routine clinical practice, such as whole blood, enhances their potential utility in detecting changes in the immunological mechanisms underlying autoimmune diseases such as RA. INTRODUCTION: MicroRNAs (miRNAs) are a group of noncoding RNAs,∼ 20 - 22 nucleotides in length, that repress target gene expression through mRNA degradation and translation inhibition. The gene encoding miR-323-3p, which is a biomarker in immune and inflammatory responses, exists in a miRNA cluster in chromosomal region 14q32.31. It has been shown that miR-323-3p associates with the pathogenesis of several diseases, such as rheumatoid arthritis, Alzheimer's disease and ectopic pregcy. AREAS COVERED: This review provides a current view on the association of miR-323-3p with several human diseases and is focused on the recent studies of miR-323-3p regulation, discussing its potential as an epigenetic biomarker and therapeutic target for these diseases. In particular, the mechanisms of miR-323-3p in these diseases and how miR-323-3p is regulated are also discussed. EXPERT OPINION: Although the exact role of miR-323-3p in these diseases has not been fully elucidated, targeting miR-323-3p may serve as a promising therapy strategy.

Is there an association between FGFR3 mutation and plagiocephaly?

Yes, FGFR3 mutation is associated with plagiocephaly. It is the most common mutation in plagiocephaly. FGFR genes have important effects on bone development, and mutations in 4 "hot spot" exons of FGFR1-3 are found in many patients with craniosynostosis and some with synostotic plagiocephaly.

To determine whether the autosomal domit fibroblast growth factor receptor 3 (FGFR3) Pro250Arg mutation causes anterior plagiocephaly, patients with either apparently sporadic unicoronal synostosis (N = 37) or other forms of anterior plagiocephaly (N = 10) were studied for this mutation. Of 37 patients with unicoronal synostosis, 4 tested positive for the Pro250Arg mutation in FGFR3, and 33 were negative for this mutation. In three mutation positive patients with full parental studies, a parent with an extremely mild phenotype was found to carry the same mutation. None of the 6 patients with nonsynostotic plagiocephaly and none of the 4 patients with additional suture synostosis had the FGFR3 mutation. Because it is impossible to predict the FGFR3 Pro250Arg mutation status based on clinical examination alone, all patients with unicoronal synostosis should be tested for it. To assess their recurrence risk, all parents of mutation positive patients should be tested regardless of their clinical findings, because the phenotype can be extremely variable and without craniosynostosis. Clinical teaching dictates that isolated unicoronal synostosis is sporadic in occurrence and is possibly related to intrauterine constraint. Despite this, isolated reports document a familial occurrence. It has previously been recognized that there may be a familial pattern of inheritance. Recently, mutations in fibroblast growth factor receptors (FGFRs) have been implicated in several syndromic craniosynostoses. At the authors' institution, mutations in FGFR3, located at chromosome 4p16, have been found to cause coronal synostosis. Two cases of unicoronal synostosis were found to have the same Pro250Arg missense mutation in FGFR3. This finding suggested that all patients with a diagnosis of unicoronal synostosis be screened for the FGFR3 mutation. Between January and December of 1996, patients with a diagnosis of plagiocephaly at the Children's Hospital of Philadelphia were evaluated for the FGFR3 mutation. Thirty-seven patients with unicoronal synostosis had mutational studies. Two additional patients were known to have the FGFR3 mutation at the onset of the study. Of the 37 patients screened, four were found to have the FGFR3 mutation, for a total of six patients with both unicoronal synostosis and the FGFR3 mutation. All patients with unicoronal synostosis were evaluated for facial dysmorphology and operative outcome. The six patients with the FGFR3 mutation had more severe cranial dysmorphology and were more likely to need surgical revision than those without the FGFR3 mutation. The occurrence of the FGFR3 mutation among patients with unicoronal synostosis provides evidence for a genetic basis of certain forms of plagiocephaly. The clinical, radiologic, and molecular findings will be an important addition to the surgical management and counseling of patients with unicoronal synostosis. PURPOSE: Craniosynostoses are premature ossifications of cranial sutures. They occur isolated and syndromic. Syndromic craniosynostoses are mainly associated with mutations of the Fibroblast Growth Factor Receptors (FGFR) 1 - 3. This paper gives an overview of the etiology and pathophysiology of isolated and syndromic craniosynostoses and discusses the molecular genetic results in 21 index cases (19 seemingly isolated craniosynostoses, 2 cases with a clinical diagnosis of Crouzon's syndrome). METHOD: Mutation analysis in exons of the FGFR 1 - 3 known to be preferentially affected in craniosynostoses was performed on DNA samples from peripheral blood and bone specimen excised at the time of surgery to correct the craniosynostosis. RESULTS: In a girl with seemingly isolated plagiocephaly we identified a P250L (749C-->T) mutation in FGFR3. Her mother showed minor signs of craniosynostosis when the family was re-evaluated. She was shown to carry the same mutation. In two patients with suspected Crouzon's syndrome 2 different mutations were detected at the same nucleotide (1025G-->A or C) and confirmed the clinical diagnosis. No mutation was found in 18/19 seemingly isolated craniosynostosis cases. CONCLUSION: In contrast to syndromic forms isolated craniosynostoses are rarely associated with mutations in FGFR. The affection of further family members is a strong indication of involvement of FGFR mutations. Because of variable expressivity, parents should be examined carefully in isolated craniosynostoses to identify minor signs. Mutations in genes known to be responsible for most of the recognizable syndromes associated with bilateral coronal synostosis can be detected by molecular testing. The genetic alterations that could cause unilateral coronal synostosis are more elusive. It is recognized that FGFR and TWIST mutations can give rise to either bilateral or unilateral coronal synostosis, even in the same family. The authors undertook a prospective study of patients presenting with synostotic frontal plagiocephaly (unilateral coronal synostosis) to Children's Hospital Boston during the period from 1997 to 2000. Mutational analysis was performed on all patients and on selected parents whenever familial transmission was suspected. Intraoperative anthropometry was used in an effort to differentiate those patients in whom a mutation was detected from those in whom it was not. The anthropometric measures included bilateral sagittal orbital-globe distance, inter medial canthal distance, and nasal angulation. Macrocephaly and palpebral angulation were also considered possible determits. There was a 2:1 female preponderance in 47 patients with synostotic frontal plagiocephaly. Mutations were found in eight of 47 patients: two patients with different single-amino-acid changes in FGFR2, three patients with FGFR3 Pro250Arg, and three patients with TWIST mutations. Another patient had craniofrontonasal syndrome for which a causative locus has been mapped to chromosome X, although molecular testing is not yet available. Two features were strongly associated with a detectable mutation in patients with synostotic frontal plagiocephaly: asymmetrical brachycephaly (retrusion of both supraorbital rims) and orbital hypertelorism. Other abnormalities in the craniofacial region and extremities were clues to a particular mutation in FGFR2, FGFR3, TWIST, or the X-linked mutation. Neither macrocephaly nor degree of nasal angulation nor relative vertical position of the lateral canthi correlated with mutational detection. An additional four patients in this study had either unilateral or bilateral coronal synostosis in an immediate relative and had anthropometric findings that predicted a mutation, and yet no genetic alteration was found. This suggests either that the authors' screening methods were not sufficiently sensitive or that perhaps there are other unknown pathogenic loci. Nevertheless, molecular testing is recommended for infants who have unilateral coronal synostosis, particularly if there are the anthropometric findings highlighted in this study or an otherwise suspicious feature in the child or a parent. Infants with either an identified or a suspected mutation usually need bilateral asymmetric advancement of the bandeau and may be more likely to require frontal revision in childhood. The aim of this study was to perform a morphometric analysis of untreated adult skulls displaying syndromic and nonsyndromic craniosynostosis. We analyzed, in detail, 42 adult craniosynostoses (18 scaphocephaly, 11 anterior plagiocephaly, 2 trigonocephaly, 9 oxycephaly, and 2 brachycephaly) from archeological (three skulls) and pathoanatomical samples (39 skulls). The univariate and bivariate measurements from the pathological skulls were compared with 40 anatomical skulls with normal cranial vault morphology. Bony signs of chronic elevated intracranial pressure (ICP) are (1) diffuse beaten copper pattern, (2) dorsum sellae erosion, (3) suture diastasis, and (4) abnormalities of venous drainage that particularly affect the sigmoid-jugular sinus complex. The mean cranial length was significantly greater in scaphocephaly than in anatomical skulls (20.3 vs 18.0 cm), and the sagittal suture was also longer (14.3 vs 11.8 cm). There were three types of suture course in the bregma region in scaphocephaly: anterior spur (28%), normal configuration (61%), and posterior spur (11%). The plagiocephaly measurements showed nonsignificant differences, and there was no correlation between the length of the anterior and middle skull base (ipsilateral anterior-posterior shortening of the skull) and incomplete or complete suture synostosis. Bony signs of chronic elevated ICP were found in 82% of cases of oxycephaly and brachycephaly. In three such cases of oxycephaly, we found a marked (1.8-2.1 cm) elevation of bregma region. One skull (Saethre-Chotzen syndrome) yielded human DNA sufficient for polymerase chain reaction (PCR)-based amplification procedures. Mutation analyses in the FGFR3 gene revealed nucleotide alterations located in the mutational hot spot at amino acid residue 250 (g.C749). The mean cranial length in adult scaphocephaly was 12% greater than anatomical skulls. A unilateral complete or incomplete coronal synostosis can be found with or without plagiocephalic deformation. Elevation of the bregma region is a bony sign of chronic elevated ICP. These data on adult craniosynostosis could be of interest for physicians dealing with craniosynostotic children.

Are CD44 variants (CD44v) associated with poor prognosis of metastasis?

Yes, several isoforms (obtained by by usage of ten variant exons in various combinations) have been causally related to metastasis.

CD44 designates a large family of proteins generated from one gene by alternative splicing. Variants of CD44 (CD44v) differ from the standard form (CD44s) by usage of ten variant exons in various combinations. Some variants have been causally related to the metastatic spread of rat tumor cells. In human mammary carcinomas and colorectal carcinomas, the expression of CD44v has also been correlated with more progressed tumor stages. Moreover, the expression of CD44v on mammary and colorectal carcinomas correlates with a bad prognosis for patient survival. The biochemical features of these CD44 isoforms that may account for both their normal functions and their roles in tumor progression are discussed. In animal models, isoforms of CD44 (CD44v) containing sequences encoded by one or several of ten different exons (v1-v10) contribute to tumour metastasis. In certain human cancers, CD44v6 expression is associated with poor prognosis. This paper examines CD44v expression in skin carcinogenesis and skin cancer metastasis. CD44v expression was studied in basal cell carcinoma (BCC), squamous cell carcinoma (SCC), primary maligt melanoma (PMM), metastases of MM (MMM), benign melanocytic naevi (BMN) and normal skin (NS) by immunohistochemistry and reverse transcript polymerase chain reaction (RT-PCR). BCC, SCC and NS expressed several CD44v, including v6, albeit in different distributions and intensities. PMM, MMM and BMN expressed isoforms containing v7/8 and v10, but failed to express epitopes encoded by v5 or v6. Thus, different CD44 isoforms are found in human skin cancers and are modulated during carcinogenesis. However, we did not observe a correlation of CD44v6 expression with metastatic potential. CD44, a cell adhesion molecule, has been implicated in tumor invasion and metastasis in certain maligcies. We studied the expression of CD44 standard (CD44s) and variant isoforms (CD44v) in 98 non-small cell lung carcinomas (NSCLCs) by immunohistochemistry and correlated the observations with clinical outcome. Formalin-fixed, paraffin-embedded archival tissues from 49 squamous cell carcinomas (SCCs) and 49 adenocarcinomas (ACs) were immunostained after microwave irradiation with monoclonal antibodies against CD44s and CD44v3, v4/5, v6, v7/8, and v10, and the results were correlated with histological tumor type, tumor stage, recurrence, and survival rates. SCCs of the lung showed strong membranous expression of each of the CD44s, v3, v4/5, v6, and v10 proteins in comparison with ACs (P < .0001). Staining for CD44 v4/5 was overwhelmingly positive in SCCs (72%) as compared with ACs (2.2%). Intense immunoreactivity for CD44v6 was present in 19 of 20 (95%) metastatic lung carcinomas. The bronchiolar basal cells and alveolar pneumocytes were positive for CD44s, v3, and v6. CD44s and variant isoform expression did not correlate with tumor stage, recurrence, and survival rates. In conclusion, there is significant immunopositivity of CD44s and variant isoforms in SCCs over ACs of the lung. Expression of CD44v6 may suggest an increased risk for local lymph node metastasis in NSCLCs. CD44v4/5 reactivity may be useful to discriminate squamoid differentiation in poorly differentiated NSCLCs. To evaluate their prognostic value, the expressions of CD44v and sialyl LeX (SLX) in colorectal cancers were studied immunohistochemically. Tissue specimens were reacted with monoclonal antibodies (mAb) CD44-1V and CSLEX-1. Of the 145 colorectal cancer patients undergoing curative resection, 59 (40.7%) were positive for mAb CD44-1V, and 40 (27.6%) were positive for mAb CSLEX-1. There was a significant correlation between the combined expression of SLX and CD44v8-10 and lymph node metastasis. The patients with tumors negative for CD44v8-10 and SLX had the most favorable prognoses. Conversely, the patients with tumors positive for both CD44v8-10 and SLX had a high recurrence rate and the poorest prognoses. In a multivariate analysis using the Cox regression model, the combined expression of SLX and CD44v8-10 emerged as an independent prognostic indicator. These results suggested that the combined expression of CD44v8-10 and SLX may be a biologic marker of prognostic significance. A number of different isoforms of CD44 generated by alternative splicing have been isolated and sequenced. There have been several reports that CD44v plays a role in the steps of the metastatic process. We examined the role of the variant CD44v8-10 in metastases of human colon cancer cell line HT29m using a monoclonal antibody reactive with the v9 product (mAb 44-1V). Pretreatment with mAb 44-1V prevented the formation of liver metastases. In addition, we found that the attachment of HT29m cells to the basement membrane matrix was inhibited by mAb 44-1V. Several reports have shown correlations between metastatic potential and expression of CD44v in human colorectal cancer. We demonstrated that CD44v8-10 and CD44v6 RNA expression was higher in carcinomas associated with liver metastases than in those without by Northern blotting. We analyzed the expression of the CD44v8-10 product in colorectal cancer immunohistochemically using mAb 44-1V, and evaluated its prognostic significance. There were significant correlations between CD 44v8-10 immunoreactivity and both lymph node and liver metastases. Patients with CD44v8-10-positive tumors had a greater relative risk of death compared with those whose tumors were CD44v8-10 negative. These results suggest that CD44v8-10 may play an important role in the adhesion of tumor cells to the capillaries of distant organs in the metastatic process, and that immunohistochemical detection of CD44v8-10 may be a biologic marker of prognostic significance. Since the CD44 variant 6(v6) molecule has been noted as a marker for tumor metastasis and prognosis in several tumors, we examined whether or not v6 is a useful marker for evaluating the prognosis of pancreatic cancer patients. In addition, we attempted to assess the clinicopathological implications for pancreatic cancer of the variant 2 (v2) isoform using a recently developed monoclonal antibody against a v2 epitope. The expression of CD44 variants was evaluated immunohistochemically in paraffin-embedded pancreatic cancer tissues from 42 patients who were confirmed surgically and histologically to have received curative resection. An indirect immunoperoxidase method was used with monoclonal antibodies against epitopes of the standard (CD44s) portion, v6 and v2. Protein expression data were evaluated statistically for any correlations with the length of survival or with histological parameters. The expression of CD44v6 and v2 was observed only in tumor cells, if at all. On the other hand, expression of total CD44 (including CD44v, as well as CD44s) was observed in both tumors and adjacent normal sites. Tumor tissue from 21 (50%) and 16 (38%) patients showed positive immunoreactivity with mAb 2F10 (anti-CD44v6) and mAb M23.6.1 (anti-CD44v2), respectively. The expression of CD44v6 and v2 was correlated with decreased overall survival (P = 0.0160 and P = 0.0125, respectively). A significant correlation was obtained between CD44v2 peptide expression and vessel invasion (P = 0.026). These results suggest that CD44v2 and CD44v6 may be useful markers for poor prognosis in curatively resected primary pancreatic cancer. CD44 variant exon (CD44v) 3 is a heparan sulfate-binding isoform of CD44. The role of CD44v3 in invasion and metastasis associated with heparan sulfate in colon cancer cell lines and cases of colon cancer was examined. Expression of CD44v3 mRNA and protein was observed in five of six human colorectal cancer cell lines. Colo320 and WiDr cells expressed CD44v3 at high levels. Heparan sulfate treatment increased the invasive activity of Colo320 and WiDr cells to rates 14.3 and 12.6 times higher, respectively, than that of untreated cells. However, heparan sulfate treatment did not affect cell growth. Repression of CD44v3 protein production by antisense S-oligodeoxynucleotide treatment reduced the binding affinities and capacities for heparan sulfate by Colo320 and WiDr cells in comparison with that of control cells, and it also reduced the invasiveness of both cell lines to one-fifth that of control cells. In heparan sulfate-treated Colo320 cells, the levels of CD44v3 protein in the Triton X-100-insoluble fraction and moesin-precipitated fraction were increased, suggesting that heparan sulfate treatment facilitates association of CD44 molecules with the cytoskeleton. Immunohistochemical analysis showed CD44v3 to be expressed in 21 of 37 (57%) colorectal cancer cases. Positive CD44v3 expression was associated with more advanced pathological stage and poorer prognosis than negative CD44v3 expression. These data support a role for CD44v3 in invasion and metastasis by colorectal carcinoma cells. The expression of variant isoforms of CD44 (CD44v) correlates with the metastatic potential of various carcinomas. In endometrial cancer, however, the significance of CD44v-expression as a prognostic indicator has not been fully investigated, nor has it been compared with that of p53, estrogen receptor or Ki67. Surgical material consisted of 14 atypical endometrial hyperplasias (AEH) and 163 endometrial carcinomas (EC). Expression of CD44s, v3 and v6 in carcinoma tissue, and other prognostic markers were immunohistochemically evaluated. The expression in the squamous differentiation was strictly excluded for the evaluation of immunohistochemistry, because the significance was different from that in the adenocarcinoma component. CD44s was frequently expressed in AEH and EC. On the other hand, CD44v3- and v6-positivities were rare or nonexistent in AEH, but were observed in 8 and 35% of EC, respectively. CD44v3-expression correlated significantly with histologic grade and lymph node metastasis. However, there was no correlation between CD44v6 expression and any clinicopathologic factor, nor were other prognostic markers expressed. Univariate analysis revealed that each CD44 was a prognostic determit in the patients with EC. However, employing multivariate analysis, there were only three independent factors: p53 overexpression, CD44v6 expression and myometrial invasion. CD44v6 expression in the adenocarcinoma component may directly affect the behavior of carcinoma and the prognosis of patients with EC.

Is Bladder training an effective method to treat urge incontinence ?

Yes. Bladder training is a simple, safe, and effective treatment in the management of mild to moderate forms of urinary incontinence in outpatient populations. It can be used as a first-line treatment or in combination with such other interventions as pelvic muscle exercises, bladder pressure biofeedback, electrical stimulation, and drug therapy. Quoted results vary from 26 to 90% . Patients with sensory urgency appeared to do better than those with detrusor instability and it is suggested that bladder training may be indicated as primary treatment in sensory urgency.

A total of 110 women who had reported urinary incontinence to their general practitioners were randomly assigned to a treatment or control group. Treatment consisted of pelvic floor exercises in the case of stress incontinence and bladder training in the case of urge incontinence. The results were measured after 3 and 12 months by a research assistant on the basis of a constructed severity scale, an incontinence diary, and a comparison by the patients themselves of their previous and current conditions. After 3 months the control group were given the same treatment. After a further 3 and 12 months, they were assessed in exactly the same way as the treatment group. After 3 months about 60% of the patients were either dry or only mildly incontinent; the mean number of wet episodes had gone down from 20 to 7, and 74% of the women felt improved or cured. These results were later corroborated by the control group. After 12 months this successful outcome was improved slightly further. It may be concluded that the majority of women with incontinence can be successfully treated by the general practitioner. The effect of this treatment continues after one year. A double-blind study of terodiline compared with placebo was performed in 58 children aged 6 to 14 years with urgency or urge incontinence. All had an unstable bladder at cystometry. A bladder regimen was emphasised during the study. Continence was improved according to micturition charting and a pad test in both groups. Terodiline at 25 mg/day, however, gave significantly better results than placebo. In patients with a subnormal bladder capacity (less than or equal to 150 ml), a significant increase in capacity was recorded on cystometry during medication with terodiline but not with placebo. The improved continence seen in the placebo group was probably due to the non-specific bladder training achieved by the child's increased awareness and adult involvement during treatment. The even better results attained in the terodiline group shows this drug to be a valuable adjunct to a bladder regimen in children with urge incontinence, particularly since no important adverse effects were noted during an 8-week period. Twenty consecutive female patients with urge incontinence and stable detrusor function on provocative rapid fill CO2-cystometry were treated as out-patients with a bladder training programme and with terodiline/placebo in a double-blind cross-over design. Frequency and incontinence episodes decreased significantly, while first sensation and cystometric bladder capacity increased. Both objectively and subjectively terodiline was significantly better than placebo with 50% (95% confidence limits 18-82) more patients improved on terodiline than on placebo. Thirty percent of the patients (95% confidence limits 12-54) relapsed after withdrawal of terodiline. At 3 months follow-up the remaining 70% were satisfied with the outcome of the training programme. Side effects were mild and reversible. Serum creatinine and alkaline phosphatase increased slightly on terodiline and the diastolic blood pressure was probably also increased by terodiline. In conclusion, female patients with idiopathic urge incontinence and stable detrusor function did respond to treatment as do female patients with urge incontinence and proven instability. Basing on our experience with 39 patients with severe urge incontinence (in one-quarter of the cases pure urge incontinence, in one-half of the cases mixed incontinence and in a further quarter of the cases neurogenic bladder disorders) a supervised programme (mictiogram) and a well-tried therapy (especially in the Anglo-Saxon countries) consisting of the triad hospitalisation/bladder training/medication therapy are presented. After an average hospitalisation period of 14 days, we were able to achieve a symptom-free state in 94% of the patients. Cure was achieved on a long-term basis in 76%. Failure of conservative therapy was due especially to severe neurogenic bladder disorders, followed by urethral obstructive insufficiency that cannot be influenced. The superimposed psychic cause of urge incontinence that should not be underestimated and often presents as a transference of unresolved emotional needs (51% of our group are psychologically unstable), is discussed. With these facts in mind, our therapy concept is translated into reality. Hospitalisation brings about a change in surroundings, making the supervision of bladder training and adjustment to medication easier, thus supplying the basis for patient compliance and success of follow-up therapy subsequent to hospitalisation and discharge from hospital. Bladder training and/or biofeedback techniques were used to treat 75 patients with frequency, urgency, nocturia and urge incontinence. Significant improvement or cure was obtained in 70 per cent of enuretic children, and 66 per cent of men and 74 per cent of women with unstable detrusor function. The clinical results correlated with cystometric reversion to stable bladder function. Patients who obtained good results showed improvement in the tested level of psychological adjustment, suggesting that psychological factors are not causes of the urological problem. 1. Urinary incontinence is a costly and prevalent problem, affecting 15% to 39% of all community residing elders. 2. Some elders suffering from urge incontinence prefer pelvic muscle exercises to bladder training as the behavioral intervention of choice. 3. Although pelvic muscle exercises are frequently associated as an intervention for stress incontinence, they have been found to be effective in significantly reducing urge incontinence. 4. Nurses are in a key position to identify and treat urinary incontinence among the elderly, and should incorporate continence restoration interventions into their practice. OBJECTIVE: Determining the factors which influence the success of training therapy in women suffering from urinary incontinence. DESIGN: Descriptive. SETTING: Thirteen general practices in Nijmegen and environs, the Netherlands. METHOD: A total of 110 women between 20 and 65 years old, suffering from urinary incontinence were examined by their general practitioners. Age, personality, parity, psychological features and type, duration, severity, beginning of the disease, as well as the presence of cystocele or prolapse were recorded. Women were asked about their own experiences regarding factors that influenced success. The treatment consisted of training of pelvic muscles in stress incontinence and bladder training in urge incontinence. Outcomes and compliance were measured 3 and 12 months after start of treatment by means of a so-called incontinence diary. RESULTS: After 3 months the mean frequency of urine loss per week diminished from 21 to 8, and after 12 months to 6 times. Compliance was the most important contribution to success. Patients were more motivated to practise when the subjective burden of the urine loss was more severe. Other features did not influence success. BACKGROUND: It has been suggested that regular clinics might improve the management of urinary incontinence in general practice. AIM: A study was undertaken to determine the prevalence of urinary incontinence among women in one general practice and the feasibility of using a health promotion clinic in its management. METHOD: Questionnaires were sent to a 10% sample of women aged 20 years and over on the practice register. Pregt women were excluded. RESULTS: Of 384 questionnaires sent to eligible women, 314 were completed correctly (82%). The overall reported prevalence of urinary incontinence was 53%; 8% of these women had urge incontinence, 46% had stress incontinence and 43% had mixed incontinence. Incontinence was positively correlated with parity and with gynaecological operation other than hysterectomy and repair of prolapse but not with perineal suturing after childbirth, delivery of a baby weighing 9 lb (4.1 kg) or more or mode of delivery. Twenty seven out of 78 incontinent women (35%) who completed a second questionnaire admitted to worrying about their incontinence but only 10 (13%) had consulted their doctor about the problem. The main reason given for not consulting was that incontinence was a minor inconvenience only. The 167 incontinent women were offered an appointment at a women's clinic but only 13 attended. Of these, 10 were entered into a 12 week treatment trial. Various treatments were offered, such as the women being taught bladder training and pelvic floor exercises. One woman was lost to follow up, and for eight out of nine women their continence had improved, both subjectively and objectively. CONCLUSION: Urinary incontinence in women is a common problem. It can be successfully diagnosed and treated in general practice but low attendance makes the health promotion clinic setting an inefficient means of achieving this. Bladder training is a simple, safe, and effective treatment in the management of mild to moderate forms of urinary incontinence in outpatient populations. It can be used as a first-line treatment or in combination with such other interventions as pelvic muscle exercises, bladder pressure biofeedback, electrical stimulation, and drug therapy. This article describes the implementation of a 6-week bladder training program for a female patient with both stress and urge incontinence. Behavioral interventions have been used for decades to treat urge incontinence and other symptoms of overactive bladder. Perhaps the earliest form of treatment was the bladder drill, an intensive intervention designed to increase the interval between voids to establish a normal frequency of urination and normalization of bladder function. Bladder training is a modification of bladder drill that is conducted more gradually on an outpatient basis and has resulted in significant reduction of incontinence in older, community-dwelling women. Multicomponent behavioral training is another form of behavioral treatment that includes pelvic floor muscle training and exercise. This intervention focuses less on voiding habits and more on altering the physiologic responses of the bladder and pelvic floor muscles. Using biofeedback or other teaching methods, patients learn strategies to inhibit bladder contraction using pelvic floor muscle contraction and other urge suppression strategies. Although behavioral and drug therapies are known to be highly effective for reducing urge incontinence, few patients are cured with either treatment alone. Thus, future research should explore ways to enhance the effectiveness of these conservative therapies. Although the mechanisms by which behavioral treatments work have not been established, there is some evidence that behavioral and drug interventions may operate by different mechanisms, suggesting that they may have additive effects and that combining them may result in better outcomes. Future research needs to examine the mechanisms by which these therapies reduce incontinence and whether combining behavioral and drug treatment will result in better outcomes than either therapy alone. OBJECTIVES: To compare the efficacy of tolterodine plus simplified bladder training (BT) with tolterodine alone in patients with an overactive bladder. PATIENTS AND METHODS: In a multicentre, single-blind study at 51 Scandinavian centres, 505 patients aged >or= 18 years with symptoms of urinary frequency (>or= 8 micturitions/24 h) and urgency, with or without urge incontinence, were randomized to oral treatment with either tolterodine 2 mg twice daily plus simplified BT or tolterodine alone. Changes in voiding diary variables were evaluated after 2, 12 and 24 weeks of treatment. The patients' perceptions of their bladder symptoms and tolerability (adverse events) were also determined. RESULTS: In all, 501 patients (75% women) were evaluable on an intention-to-treat basis (244 on tolterodine + BT and 257 on tolterodine alone). Tolterodine significantly reduced the voiding frequency and increased the volume voided per void at all sample times; these effects were significantly increased by adding BT. At the end of the study the median percentage reduction in voiding frequency was greater with tolterodine + BT than with tolterodine alone (33% vs 25%, P < 0.001), while the median percentage increase in volume voided per void was 31% with tolterodine + BT and 20% with tolterodine alone (P < 0.001). There was a median of 81% fewer incontinence episodes than at baseline with tolterodine alone, which was not significantly different from that with tolterodine + BT (- 87%). The two groups had comparable median percentage reductions in urgency episodes. Some 76% of patients on tolterodine + BT reported an improvement in their bladder symptoms relative to baseline, compared with 71% on tolterodine alone. Tolterodine was well tolerated; the most common adverse event was mild dry mouth. CONCLUSION: Tolterodine 2 mg twice daily is an effective and well tolerated treatment for an overactive bladder, the effectiveness of which can be augmented by a simplified BT regimen. OBJECTIVES: To evaluate, in a prospective study, the effectiveness of a bladder training program. Daytime and/or nighttime wetting as a consequence of functional urinary incontinence is a common problem in childhood. Various treatment options are available, including with cognitive-behavioral "bladder training." METHODS: Sixty patients (age 8 to 12 years) with urge incontinence or dysfunctional voiding were evaluated. After a no-treatment control period (average 6 months), patients underwent a 6-day bladder training course, which was offered either as inpatient or outpatient training, leaving the choice to the patients' parents. Clinical assessments were recorded at the beginning of the control period, at training entry and training completion, and after 1 (inpatient training group only), 3, and 6 months. RESULTS: Six months after training completion, 64.1% and 64.7% of the inpatient and outpatient groups with daytime wetting and 51.5% and 17.7% of the inpatient and outpatient groups with nighttime wetting were cured or had improved, respectively. The spontaneous cure rate during the 6-month control period was 0% to 20.5%. Of the inpatient group with urge incontinence, the functional bladder capacity increased by 15%. The children aged 9 to 12 years in the inpatient group had significantly greater cure rates than the 8-year-old children. CONCLUSIONS: Compared with the control period, the bladder training program evaluated in this study resulted in significantly greater success rates. The results lead to the assumption that children with nighttime wetting treated in the inpatient training will succeed better than those in outpatient training. The cure and improvement rates of daytime wetting were greater than those for nighttime wetting. Two years after revision of the practice guideline 'Urinary incontinence' from the Dutch College of General Practitioners, it is time for a summary of the most important changes. The use of a bladder diary is recommended. In primary care, a stress test does not provide more information than history taking. Routine urodynamic testing is not indicated for patients presenting to their general practitioner with urinary incontinence. Treatment of stress, urge and mixed incontinence can usually be commenced in primary care; pelvic floor exercises and bladder training are preferred. If bladder training is not effective for urge incontinence, anticholinergic drugs should be considered. The use of oral and vaginal oestrogens and flavoxate is no longer recommended. The part "Special pharmacology of the aged" of this guideline contains recommendations for typical conditions in the family doctors practice: in the January issue 2009 dementia and Morbus Parkinson, in this issue osteoporosis and urinary incontinence and in the next issue rectal incontinence and obstipation. This issue of the IJCPT contains the third part of the Pharmacotherapy guidelines for the aged by family doctors for family doctors. Part 3: Osteoporosis and urinary incontinence. Osteoporosis is a systematic disease characterized by low bone mass and declining bone structure. Exercise, adequate diet, nicotine abstinence as well as reduction of alcohol consumption may counteract the progression of the disease. Osteoporosis manifests in bone fractures with minimal trauma. Attention must be given to the risk of falling, e.g., by avoiding drugs that increase the risk of falling: e.g., psychotropic agents, analgesic drugs and antiarrhythmic agents. Specific osteoporosis medication e.g. calcium, vitamin D, biphosphonates and SERM (selective estrogen receptor modulators) is evaluated by family doctors according to indication, dosage, contraindications, long-term therapy and nature of any fracture. Duration of therapy is at least 3 - max. 5 years followed by reassessment of indication. There are 3 types of urine incontinence (urge-, stress-, and overflow-incontinence). Another standardization of urinary incontinence follows dysfunctions of the pelvic floor: detrusor muscle-dependent, due to sphincter spasm, prostate gland dependent. Urge incontinence with a dysfunction of the detrusor muscle is the most common type. Mixed types are frequent. Non-drug measures (e.g. pelvic muscle training, bladder training, toilet training are first choice treatments. Drug therapy (estrogen, imipramine) are without proven effect. OBJECTIVES: To evaluate the role of cystometry in the diagnostic evaluation of patients with symptoms of overactive bladder, by comparing the treatment outcome in those with and without urodynamically proven bladder instability. METHODS: Prospective observational study performed at Urogynaecology Division, the Kidney Center Post-Graduate institute of nephro-urology, Karachi. Forty six patients with symptoms of overactive bladder, i.e., frequency (> or =8 voids/24 hours), nocturia, urgency with or without urge incontinence, were included. Patients were recruited solely on their symptoms of overactive bladder. All patients, irrespective of the results of cystometry were subsequently treated with oxybutynin 2.5 mg twice daily along with bladder training. Involuntary detrusor contraction over base line during filling are considered significant (AUA Update series). Following variables were compared in those with or without urodynamically proven bladder instability: the bladder volume and amplitude of detrusor contraction at first and maximum detrusor contractions, the treatment outcome and relapse rate The complications of the procedure were noted. RESULTS: Total number of 46 women, aged between 21-74 years with symptoms of overactive bladder were subjected to cystometry. The audit of cystometry showed unstable bladder in 17 (36.9%), while rest of the patients 29 (63%) had normal stable bladder with normal emptying. The comparison of treatment outcome in the urodynamically stable and unstable bladder revealed out of 17 unstable bladder with symptoms of OAB in 09 (60%) and 05 (29.4%), a 100% cure rate was observed after 3 and 6 months of treatment respectively. Of the 29 patients with stable bladder and symptoms of OAB, 100% cure rate was achieved in 20 (68.9%) and 06 (20.6%) patients respectively. While in 3 patients in both groups, decrease of symptoms upto 75% after 6 months of treatment was observed. The median volume was less and amplitude of first and maximum detrusor contraction were more in unstable than stable bladder but it was not significant statistically. CONCLUSION: Conventional Cystometry showed poor co-relation with Lower urinary tract symptoms (LUT). Both urodynamically proven unstable and stable bladder showed nearly equal improvement with treatment Overactive bladder (OAB), as defined by the International Continence Society, is characterized by a symptom complex including urinary urgency with or without urge incontinence, usually associated with frequency and nocturia. OAB syndrome has an incidence reported from six European countries ranging between 12-17%, while in the United States; a study conducted by the National Overactive Bladder Evaluation program found the incidence at 17%. In Asia, the prevalence of OAB is reported at 53.1%. In about 75%, OAB symptoms are due to idiopathic detrusor activity; neurological disease, bladder outflow obstruction (BOO) intrinsic bladder pathology and other chronic pelvic floor disorders are implicated in the others. OAB can be diagnosed easily and managed effectively with both non-pharmacological and pharmacological therapies. The first-line treatments are lifestyle interventions, bladder training, pelvic floor muscle exercises and anticholinergic drugs. Antimuscarinics are the drug class of choice for OAB symptoms; with proven efficacy, and adverse event profiles that differ somewhat. OBJECTIVE: The objective of the study was to evaluate if a mindfulness-based stress reduction program is a viable treatment worthy of further evaluation for the treatment of urinary urge incontinence. METHODS: This was a single-arm pilot study of 7 women who participated in an 8-week mindfulness-based stress reduction program to evaluate its effectiveness in reducing urinary leakage episodes. Improvement was measured by 3-day bladder diary, Overactive Bladder Symptom and Quality of Life-Short Form, Health-Related Quality of Life, and Patient Global Impression of Improvement. Outcome data were analyzed by means of paired t tests. RESULTS: Mean incontinence episodes per day decreased from 4.14 (SD, 1.96; range, 2.67-7.67) at baseline to 1.23 (SD, 0.93; range, 0.33-2.67) after treatment (P = 0.0005 for change). After treatment, 5 of 7 women were improved based on the Patient Global Impression of Improvement, and 2 were unchanged. Significant improvements on both Health-Related Quality of Life and Overactive Bladder Symptom and Quality of Life-Short Form were reported after treatment. Results were sustained at 1 year in 4 of 7 women. Two women sought treatment, and one was lost to follow-up at 12 months. CONCLUSIONS: Mindfulness-based stress reduction appears to be a treatment worthy of further study, as in the short term, it is as effective as historical studies of drug treatment and bladder training in reducing urge incontinence and incontinence-related quality of life.

What is the scope of the OMIA database?

Online Mendelian Inheritance in Animals (OMIA) is a comprehensive, annotated catalogue of inherited disorders and other familial traits in animals. OMIA is a comprehensive resource of phenotypic information on heritable animal traits and genes in a strongly comparative context, relating traits to genes where possible.

In addition to maintaining the GenBank nucleic acid sequence database, the National Center for Biotechnology Information (NCBI) provides analysis and retrieval resources for the data in GenBank and other biological data made available through the NCBI web site. NCBI resources include Entrez, the Entrez Programming Utilities, MyNCBI, PubMed, PubMed Central, Entrez Gene, the NCBI Taxonomy Browser, BLAST, BLAST Link (BLink), Electronic PCR, OrfFinder, Spidey, Splign, RefSeq, UniGene, HomoloGene, ProtEST, dbMHC, dbSNP, Cancer Chromosomes, Entrez Genomes and related tools, the Map Viewer, Model Maker, Evidence Viewer, Clusters of Orthologous Groups (COGs), Retroviral Genotyping Tools, HIV-1/Human Protein Interaction Database, Gene Expression Omnibus (GEO), Entrez Probe, GENSAT, Online Mendelian Inheritance in Man (OMIM), Online Mendelian Inheritance in Animals (OMIA), the Molecular Modeling Database (MMDB), the Conserved Domain Database (CDD), the Conserved Domain Architecture Retrieval Tool (CDART) and the PubChem suite of small molecule databases. Augmenting many of the web applications is custom implementation of the BLAST program optimized to search specialized data sets. All of the resources can be accessed through the NCBI home page at www.ncbi.nlm.nih.gov.

What is the effect of methotrexate in treating uveitis due to juvenile idiopathic arthritis ?

The first-line standard therapy for uveitis is topical and systemic corticosteroids, often reinforced by methotrexate as a second-line disease-modifying antirheumatic drug (DMARD). MTX has a topical steroid sparing effect as well. Early treatment with MTX is advocated to prevent complications such as cataract. There are no trial data on the effect of MTX. Most experience among DMARD's/ immunosuppressive drugs has been obtained with methotrexate (MTX) in juvenile idiopathic arthritis. However, controlled studies in uveitis are still missing, so that treatment with MTX and all other immunosuppressive drugs (ciclosporine A, azathioprine, mycophenolate mofetil) only reaches an evidence level III (expert opinion, clinical experience or descriptive study). Biologic DMARDs can be used with Methotrexate in refractory uveitis as well.

PURPOSE: To identify the possible risk factors for the development of cataract requiring surgery in children with juvenile idiopathic arthritis (JIA)-associated uveitis. DESIGN: Retrospective cohort study. METHODS: Data of 53 children with JIA-associated uveitis, of whom 27 had undergone cataract extraction (CE), were obtained. The main outcome measure, the interval between the onset of uveitis and the first CE (U-CE interval), was examined in relation to clinical and ophthalmologic characteristics and treatment strategies before CE. RESULTS: A shorter U-CE interval was found for children with posterior synechia vs those without posterior synechia (hazard ratio [HR], 3.57; 95% confidence interval [CI], 1.33 to 10.00). No significant difference was found for children in whom the uveitis was the first manifestation of JIA vs those in whom arthritis was the first manifestation of JIA (HR, 1.59; 95% CI, 0.63 to 4.00) and children treated with periocular corticosteroid injections vs those not treated with periocular corticosteroid injections (HR, 3.23; 95% CI, 0.95 to 11.11). Children treated with methotrexate (MTX) had a longer U-CE interval than children not treated with MTX (HR, 0.29; 95% CI, 0.10 to 0.87). CONCLUSIONS: The risk factor for development of early cataract requiring surgery in children with JIA-associated uveitis is the presence of posterior synechia at the time of diagnosis of uveitis. However, early treatment with MTX is associated with a mean delay in the development of cataract requiring surgery of 3.5 years. Treatment of childhood uveitis associated with juvenile idiopathic arthritis (JIA) is a challenge for both, ophthalmologists and pediatricians. In this study, we use the tools of evidence based medicine (EBM) to analyse studies concerning disease-modifying antirheumatic drugs (DMARD)/ immunosuppressive drugs and tumor necrosis factor alpha (TNFalpha) blocking agents. Most experience among DMARD's/ immunosuppressive drugs has been obtained with methotrexate (MTX) in juvenile idiopathic arthritis. However, controlled studies in uveitis are still missing, so that treatment with MTX and all other immunosuppressive drugs (ciclosporine A, azathioprine, mycophenolate mofetil) only reaches an evidence level III (expert opinion, clinical experience or descriptive study). Studies on TNFalpha-blocking agents reach an evidence level II-III, depending on the substance. In future, MTX will have to be examined in comparison to the new biological substance classes (e.g., tumor necrosis factor-alpha-blockers) for the treatment of uveitis in juvenile idiopathic arthritis. Controlled studies which have led to the approval of drugs for JIA are needed for uveitis in order to have the most effective and safe therapy for children with uveitis, who do not respond to conventional therapy with local and systemic steroids. Biologic agents have been designed with the help of immunological studies to target particular areas of the immune system which are thought to play a role in the pathogenesis of disease. Etanercept is a soluble anti-tumor necrosis factor alpha (TNF-alpha) agent licensed for the treatment of active poly-articular juvenile idiopathic arthritis (JIA) in children aged 4 to 17 years who have failed to respond to methotrexate alone, or who have been intolerant of methotrexate. The safety and efficacy of etanercept in this patient group has been established by one randomized controlled trial and several longitudinal studies. This, together with the fact that until recently etanercept was the only anti-TNF licensed in JIA, has made it the most common first choice biologic for many clinicians. However, there are still many uswered questions about etanercept, including its efficacy and safety in different subtypes of JIA, in children under 4 years of age and in those with uveitis. There are still concerns about the long term safety of TNF antagonists in the pediatric age group and uswered questions about increased risks of maligcy and infection. Although adult studies are useful to improve understanding of these risks, they are not a substitute for good quality pediatric research and follow-up studies. Adult trials often include greater numbers of patients. However, they evaluate a different population and drug behavior may vary in children due to differences in metabolism, growth and impact on a developing immune system. In addition, rheumatoid arthritis is a different disease than JIA. Clinicians need to carefully weigh up the risk benefit ratio of anti-TNF use in children with JIA and push for robust clinical trials to address the questions that remain uswered. This article summarizes the evidence available for use of etanercept in children with JIA and highlights aspects of treatment in need of further research. PURPOSE: To evaluate the efficacy of methotrexate (MTX) and the effect of its withdrawal on relapse rate of uveitis associated with juvenile idiopathic arthritis (JIA). DESIGN: Retrospective case series. METHODS: Data of 22 pediatric JIA patients who were being treated with MTX for active uveitis were studied retrospectively. Relapse rate after the withdrawal of MTX was established. Anterior chamber (AC) inflammation, topical steroid use during the first year of MTX treatment, and associations of relapses after the withdrawal were evaluated statistically. Duration of MTX treatment and its withdrawal was determined individually in collaboration with a rheumatologist with an intention to continue the treatment for at least 1 year and to withdraw in case of inactivity of uveitis and arthritis. Inactivity of uveitis was defined as the presence of ≤0.5+ cells in the AC. RESULTS: Eighteen patients (18/22; 82%) showed improvement of their uveitis with a significant decrease in activity of AC inflammation after a minimal period of 3 months of MTX treatment. A topical steroid-sparing effect was observed when MTX was administered for a period of 3 to 9 months. MTX was discontinued because of inactive uveitis in 13 patients. In 9 patients (8/13; 69%) a relapse of uveitis was observed after a mean time of 7.5 months (± SD 7.3). Six patients (6/13; 46%) had a relapse within the first year after the withdrawal. Relapse-free survival after withdrawal of MTX was significantly longer in patients who had been treated with MTX for more than 3 years (P = .009), children who were older than 8 years at the moment of withdrawal (P = .003), and patients who had an inactivity of uveitis of longer than 2 years before withdrawal of MTX (P = .033). Longer inactivity under MTX therapy was independently protective for relapses after the withdrawal (hazard ratio = 0.07; 95% confidence interval 0.01-0.86; P = .038), which means that 1-year increase of duration of inactive uveitis before the withdrawal of MTX results in a decrease of hazard for new relapse of 93%. CONCLUSIONS: A high number of patients with inactive uveitis relapse quickly after the withdrawal of MTX. Our results suggest that a longer period of inactivity prior to withdrawal and a longer treatment period with MTX reduce the chance of relapse after withdrawal. BACKGROUND: The purpose of this study was to investigate the long-term effects of adalimumab, a tumor necrosis factor alpha antagonist, in the treatment of uveitis associated with juvenile idiopathic arthritis. METHODS: Adalimumab was initiated in 94 patients with juvenile idiopathic arthritis to treat active arthritis and/or active associated uveitis. In 18 patients, therapy was discontinued after a short period because of inefficacy or side effects. The activity of uveitis (using Standardized Uveitis Nomenclature [SUN] criteria and clinical examination) and arthritis (number of swollen or active joints) was evaluated at the start and at end of the study. RESULTS: At the end of the study, uveitis was under good clinical control in two thirds of 54 patients (31% did not need any local treatment and 35% used only 1-2 corticosteroid drops a day), and one third had active uveitis (at least three corticosteroid drops a day). According to SUN criteria, adalimumab treatment for uveitis showed improved activity (a two-fold decrease in uveitis activity) in 28% of patients, with a moderate response in 16 patients, no change in a further 16 patients, and worsening activity (a two-fold increase in uveitis activity) in 13% of patients. The overall proportion of patients with active arthritis decreased. At the beginning of the study, 69% of patients with uveitis had more than two active joints, and at the end of the study only 27% had active joint disease. In 27 patients with juvenile idiopathic arthritis without uveitis on adalimumab, the number of active joints decreased from 93% to 59%. Systemic corticosteroid treatment could be stopped in 22% of patients with uveitis and in 11% of those without uveitis. Most of the patients had received methotrexate, other immunosuppressive therapy, or other biological drugs before initiating adalimumab. CONCLUSION: Adalimumab is a valuable option in the treatment of uveitis associated with active juvenile idiopathic arthritis. OBJECTIVE: To characterize disease-modifying antirheumatic drug (DMARD) use for children with juvenile idiopathic arthritis (JIA) in the United States and to determine patient factors associated with medication use. METHODS: We analyzed cross-sectional baseline enrollment data from the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry from May 2010 through May 2011 for children with JIA. Current and prior medication use was included. We used parsimonious backward stepwise logistic regression models to calculate OR to estimate associations between clinical patient factors and medication use. RESULTS: We identified 2748 children with JIA with a median disease duration of 3.9 years from 51 US clinical sites. Overall, 2023 (74%) had ever received a nonbiologic DMARD and 1246 (45%) had ever received a biologic DMARD. Among children without systemic arthritis, methotrexate use was most strongly associated with uveitis (OR 5.2, 95% CI 3.6-7.6), anticitrullinated protein antibodies (OR 4.5, 95% CI 1.7-12), and extended oligoarthritis (OR 4.1, 95% CI 2.5-6.6). Among children without systemic arthritis, biologic DMARD use was most strongly associated with rheumatoid factor (RF)-positive polyarthritis (OR 4.3, 95% CI 2.9-6.6), psoriatic arthritis (PsA; OR 3.0, 95% CI 2.0-4.4), and uveitis (OR 2.8, 95% CI 2.1-3.7). Among children with systemic arthritis, 160 (65%) ever received a biologic DMARD; tumor necrosis factor inhibitor use was associated with polyarthritis (OR 2.5, 95% CI 3.8-16), while interleukin 1 inhibitor use was not. CONCLUSION: About three-quarters of all children with JIA in the CARRA Registry received nonbiologic DMARD. Nearly one-half received biologic DMARD, and their use was strongly associated with RF-positive polyarthritis, PsA, uveitis, and systemic arthritis.

Which are the enzymes involved in the addition of 7-methylguanosine in mRNA?

The 7-methylguanosine cap added to the 5′ end of mRNA is essential for efficient gene expression and cell viability. Methylation of the guanosine cap is necessary for the translation of most cellular mRNAs in all eukaryotic organisms in which it has been investigated. In some experimental systems, cap methylation has also been demonstrated to promote transcription, splicing, polyadenylation and nuclear export of mRNA. In the addition of 7-methylguanosine in mRNA involved the RNA polymerase II, RNA guanylyltransferase and RNA guanine-7 methyltransferase enzymes.

1. Decapped tobacco mosaic virus (TMV) RNA and rabbit globin mRNA were prepared by enzymic treatment of RNAs with nucleotide pyrophosphatase purified from potato. The extent of removal of 5'-terminal 7-methylguanosine 5'-monophosphate (m7GMP) from TMV RNA was at least 97% as estimated by labeling of the 5' termini in vitro with S-adenosyl[methyl-3H]methionine catalysed by vaccinia virus methyltransferases. 2. The effect of enzymic decapping was compared with the effect of cap analogs on mRNAs translation in a nuclease-treated rabbit reticulocyte lysate and in a wheat germ extract. When translation was studied at low K+ concentration, little or no dependence on 5'-terminal 7-methylguanosine was found with either cell-free system. The importance of the 5'-terminal cap for the efficient translation of TMV RNA and globin mRNA increased as the concentration of K+ in a protein-synthesis system was raised. In a reticulocyte lysate analogs and enzymic decapping had a similar effect on translation. In a wheat germ extract, mRNA decapping resulted in a more pronounced decrease of mRNA activity, presumably due to the increased susceptibility of decapped mRNAs to the nucleases present in this protein synthesis system. 3. The requirement for a 5'-terminal cap was similar for the synthesis of 130,000-Mr and 165,000-Mr polypeptides coded by TMV RNA. This indicates that both proteins may be initiated at the common site close to the 5' terminus. The 5' termini of many viral and cellular mRNAs contain sequences of the type m7G(5")pppNm. An RNA (guanine-7-)-methyltransferase that specifically methylates the 5'-terminal guanosine residue of RNAs ending in the dinucleoside triphosphate G(5')pppN- has been purified from the cytoplasm of HeLa cells. Approximately two-thirds of the methyltransferase activity detected in an assay employing umnethylated vaccinia virus mRNA as acceptor was located in the cytoplasm when cells were disrupted by Dounce homogenization; 30% of the cytoplasmic activity was associated with ribosomes but was removed by washing with 0.5 M KCl. The enzyme was purified 165-fold from the cytoplasm by removing nucleic acid by phase partition followed by ammonium sulfate precipitation and column chromatography on DEAE-cellulose, denatured DNA-agarose, and CM-Sephadex. The partially purified enzyme preparation methylated heterologous tRNAs as well as vaccinia mRNA, but the tRNA methyltransferases could be separated from the mRNA activity by sucrose gradient sedimentation and gel filtration on Sephadex G-200. The product of the partially purified enzyme using vaccinia mRNA as substrate was exclusively 7-methylguanosine located in the terminal dinucleoside triphosphate. In addition to RNAs and synthetic polyribonucleotides terminating in a dinucleoside triphosphate, free G(5')pppG could be methylated but GTP, GDP, and G(5')pppG could not. The enzyme also methylated the dinucleoside diphosphate G(5')pppG but much less efficiently than G(5')pppG. An S20, W of 3.8, a Stokes radius of 3.6 nm, and a molecular weight of 56,000 were obtained from sucrose gradient sedimentation and Sephadex G-200 column chromatography. Characterization of the donor and acceptor specificities of mRNA guanylyltransferase and mRNA (guanine-7-)-methyltransferase isolated from vaccinia virus cores has enabled us to discriminate between alternative reaction sequences leading to the formation of the 5'-terminal m7G(5')pppN-structure. The mRNA guanylyltransferase catalyzes the transfer of a residue of GMP from GTP to acceptors which possess a 5'-terminal diphosphate. A diphosphate-terminated polyribonucleotide is preferred to a mononucleoside diphosphate as an acceptor suggesting that the guanylyltransferase reaction occurs after initiation of RNA synthesis. Although all of the homopolyribonucleotides tested (pp(A)n, pp(G)n, pp(I)n, pp(U)n, and pp(C)n) are acceptors for the mRNA guanylyltransferase indicating lack of strict sequence specificity, those containing purines are preferred. Only GTP and dGTP are donors in the reaction; 7-methylguanosine (m7G) triphosphate specifically is not a donor indicating that guanylylation must precede guanine-7-methylation. The preferred acceptor of the mRNA (guanine-7-)-methyltransferase is the product of the guanylyltransferase reaction, a polyribonucleotide with the 5'-terminal sequence G(5')pppN-. The enzyme can also catalyze, but less efficiently methylation of the following: dinucleoside triphosphates with the structure G(5')pppN, GTP, dGTP, ITP, GDP, GMP, and guanosine. The enzyme will not catalyze the transfer of methyl groups to ATP, XTP, CTP, UTP, or to guanosine-containing compounds with phosphate groups in either positions 2' or 3' or in 3'-5' phosphodiester linkages. The latter specificity provides an explanation for the absence of internal 7-methylguanosine in mRNA. In the presence of PPi, the mRNA guanylyltransferase catalyzes the pyrophosphorolysis of the dinucleoside triphosphate G(5')pppA, but not of m7G(5')pppA. Since PPi is generated in the process of RNA chain elongation, stabilization of the 5'-terminal sequences of mRNA is afforded by guanine-7-methylation. The translation of polyadenylated and of non-polyadenylated RNA obtained from lactating rat mammary gland was almost totally inhibited by 0.5 mM 7-methylguanosine-5'-phosphate in the wheat-germ cell-free system. This inhibition was maintained during the preparation of the 9S whey-protein mRNA and of the 12S and 15S casein mRNAs. Chemical decapping of these mRNAs caused a similar reduction of their activity. Although a large fraction of milk-protein mRNAs have been reported to lack 3'-polyadenylation, these results show that the mRNAs in the mammary gland do contain a 5'-terminal 7-methylguanosine cap. The superfamily of protein tyrosine phosphatases (PTPs) includes at least one enzyme with an RNA substrate. We recently showed that the RNA triphosphatase domain of the Caenorhabditis elegans mRNA capping enzyme is related to the PTP enzyme family by sequence similarity and mechanism. The PTP most similar in sequence to the capping enzyme triphosphatase is BVP, a dual-specificity PTP encoded by the Autographa californica nuclear polyhedrosis virus. Although BVP previously has been shown to have modest tyrosine and serine/threonine phosphatase activity, we find that it is much more potent as an RNA 5'-phosphatase. BVP sequentially removes gamma and beta phosphates from the 5' end of triphosphate-terminated RNA, leaving a 5'-monophosphate end. The activity was specific for polynucleotides; nucleotide triphosphates were not hydrolyzed. A mutant protein in which the active site cysteine was replaced with serine was inactive. Three other dual-specificity PTPs (VH1, VHR, and Cdc14) did not exhibit detectable RNA phosphatase activity. Therefore, capping enzyme and BVP are members of a distinct PTP-like subfamily that can remove phosphates from RNA. A combination of T4 polynucleotide kinase, Escherichia coli alkaline phosphatase, yeast Saccharomyces cerevisiae capping enzyme consisting of alpha (RNA guanylyltransferase) and beta (RNA 5'-triphosphatase) subunits. and its alpha subunit without RNA 5'-phosphatase activity was used to establish a simple enzymatic method for determination of RNA species with 5'-hydroxyl, 5'-monophosphate, 5'-diphosphate or 5'-triphosphate termini. Using this method, we found that viral genome RNA (vRNA) segments of both A-type and C-type influenza viruses carry tri- or diphosphates at their 5' termini. The conclusion was based on the observations that: (i) 5' phosphorylation of vRNAs by T4 polynucleotide kinase takes place only after phosphatase treatment; and (ii) capping of vRNAs can be observed with both the intact yeast capping enzyme and its alpha subunit alone devoid of RNA 5'-triphosphatase activity; but (iii) the level of capping is higher for the alphabeta holoenzyme than the alpha subunit though the relative level varies depending on RNA preparations. The results support the de novo initiation for the RNA replication although transcription of influenza vRNAs is initiated by host cell capped RNAs as primers. Localization of bicoid (bcd) mRNA to the anterior and oskar (osk) mRNA to the posterior of the Drosophila oocyte is critical for embryonic patterning. Previous genetic studies implicated exuperantia (exu) in bcd mRNA localization, but its role in this process is not understood. We have biochemically isolated Exu and show that it is part of a large RNase-sensitive complex that contains at least seven other proteins. One of these proteins was identified as the cold shock domain RNA-binding protein Ypsilon Schachtel (Yps), which we show binds directly to Exu and colocalizes with Exu in both the oocyte and nurse cells of the Drosophila egg chamber. Surprisingly, the Exu-Yps complex contains osk mRNA. This biochemical result led us to reexamine the role of Exu in the localization of osk mRNA. We discovered that exu-null mutants are defective in osk mRNA localization in both nurse cells and the oocyte. Furthermore, both Exu/Yps particles and osk mRNA follow a similar temporal pattern of localization in which they transiently accumulate at the oocyte anterior and subsequently localize to the posterior pole. We propose that Exu is a core component of a large protein complex involved in localizing mRNAs both within nurse cells and the developing oocyte. The crystal structures of the full-length human eukaryotic initiation factor (eIF) 4E complexed with two mRNA cap analogues [7-methylguanosine 5'-triphosphate (m(7)GTP) and P(1)-7-methylguanosine-P(3)-adenosine-5',5'-triphosphate (m(7)GpppA)] were determined at 2.0 A resolution (where 1 A=0.1 nm). The flexibility of the C-terminal loop region of eIF4E complexed with m(7)GTP was significantly reduced when complexed with m(7)GpppA, suggesting the importance of the second nucleotide in the mRNA cap structure for the biological function of eIF4E, especially the fixation and orientation of the C-terminal loop region, including the eIF4E phosphorylation residue. The present results provide the structural basis for the biological function of both N- and C-terminal mobile regions of eIF4E in translation initiation, especially the regulatory function through the switch-on/off of eIF4E-binding protein-eIF4E phosphorylation. Cellular eukaryotic mRNAs are capped at their 5' ends with a 7-methylguanosine nucleotide, a structural feature that has been shown to be important for conferring mRNA stability, stimulating mRNA biogenesis (splicing, poly(A) addition, nucleocytoplasmic transport), and increasing translational efficiency. Whereas yeast mRNAs have no additional modifications to the cap, called cap0, higher eukaryotes are methylated at the 2'-O-ribose of the first or the first and second transcribed nucleotides, called cap1 and cap2, respectively. In the present study, we identify the methyltransferase responsible for cap1 formation in human cells, which we call hMTr1 (also known as FTSJD2 and ISG95). We show in vitro that hMTr1 catalyzes specific methylation of the 2'-O-ribose of the first nucleotide of a capped RNA transcript. Using siRNA-mediated knockdown of hMTr1 in HeLa cells, we demonstrate that hMTr1 is responsible for cap1 formation in vivo. The Myc proteins c-Myc and N-Myc are essential for development and tissue homoeostasis. They are up-regulated by growth factors and transmit the signal for cell growth and proliferation. Myc proteins are also prominent oncogenes in many human tumour types. Myc proteins regulate the transcription of protein-encoding mRNAs and the tRNAs and rRNA which mediate mRNA translation into protein. Myc proteins also up-regulate translation by increasing addition of the 7-methylguanosine cap (methyl cap) to the 5' end of pre-mRNA. Addition of the methyl cap increases the rate at which transcripts are translated by directing RNA modifications and translation initiation. Myc induces methyl cap formation by promoting RNA polymerase II phosphorylation which recruits the capping enzymes to RNA, and by up-regulating the enzyme SAHH (S-adenosylhomocysteine hydrolase), which neutralizes the inhibitory by-product of methylation reactions. Myc-induced cap methylation is a major effect of Myc function, being necessary for activated protein synthesis, cell proliferation and cell transformation. Inhibition of cap methylation is synthetic lethal with elevated Myc protein expression, which indicates the potential for cap methylation to be a therapeutic target. The c-myc proto-oncogene regulates the expression of 15% to 20% of all genes, depending on the cell type, and the regulation is usually modest (1.5- to 2.0-fold). The authors discovered that in addition to regulating mRNA abundance, c-Myc regulates the formation of the 7-methylguanosine cap on many mRNAs, including transcriptional target genes and others not transcriptionally activated. Because the 7-methylguanosine cap is required for effective translation, enhanced methyl cap formation leads to increased protein production from Myc-responsive genes that exceeds the transcriptional induction. Increased cap methylation is linked to Myc-dependent enhanced activity of 2 critical kinases, TFIIH and p-TEFb, which phosphorylate the RNA polymerase II carboxy-terminal domain (CTD). Phosphorylation of the CTD recruits RNGTT and RNMT, the enzymes involved in mRNA capping, to the nascent transcript. Evidence is accumulating that enhanced cap methylation makes a significant contribution to Myc-dependent gene regulation and protein production. The function of cytoplasmic PABPs [poly(A)-binding proteins] in promoting mRNA translation has been intensively studied. However, PABPs also have less clearly defined functions in mRNA turnover including roles in default deadenylation, a major rate-limiting step in mRNA decay, as well as roles in the regulation of mRNA turnover by cis-acting control elements and in the detection of aberrant mRNA transcripts. In the present paper, we review our current understanding of the complex roles of PABP1 in mRNA turnover, focusing on recent progress in mammals and highlighting some of the major questions that remain to be addressed. Decapping scavenger (DcpS) enzymes catalyze the cleavage of a residual cap structure following 3' → 5' mRNA decay. Some previous studies suggested that both m(7)GpppG and m(7)GDP were substrates for DcpS hydrolysis. Herein, we show that mononucleoside diphosphates, m(7)GDP (7-methylguanosine diphosphate) and m(3)(2,2,7)GDP (2,2,7-trimethylguanosine diphosphate), resulting from mRNA decapping by the Dcp1/2 complex in the 5' → 3' mRNA decay, are not degraded by recombit DcpS proteins (human, nematode, and yeast). Furthermore, whereas mononucleoside diphosphates (m(7)GDP and m(3)(2,2,7)GDP) are not hydrolyzed by DcpS, mononucleoside triphosphates (m(7)GTP and m(3)(2,2,7)GTP) are, demonstrating the importance of a triphosphate chain for DcpS hydrolytic activity. m(7)GTP and m(3)(2,2,7)GTP are cleaved at a slower rate than their corresponding dinucleotides (m(7)GpppG and m(3)(2,2,7)GpppG, respectively), indicating an involvement of the second nucleoside for efficient DcpS-mediated digestion. Although DcpS enzymes cannot hydrolyze m(7)GDP, they have a high binding affinity for m(7)GDP and m(7)GDP potently inhibits DcpS hydrolysis of m(7)GpppG, suggesting that m(7)GDP may function as an efficient DcpS inhibitor. Our data have important implications for the regulatory role of m(7)GDP in mRNA metabolic pathways due to its possible interactions with different cap-binding proteins, such as DcpS or eIF4E. Gene expression in eukaryotes is dependent on the mRNA methyl cap which mediates mRNA processing and translation initiation. Synthesis of the methyl cap initiates with the addition of 7-methylguanosine to the initiating nucleotide of RNA pol II (polymerase II) transcripts, which occurs predomitly during transcription and in mammals is catalysed by RNGTT (RNA guanylyltransferase and 5' phosphatase) and RNMT (RNA guanine-7 methyltransferase). RNMT has a methyltransferase domain and an N-terminal domain whose function is unclear; it is conserved in mammals, but not required for cap methyltransferase activity. In the present study we report that the N-terminal domain is necessary and sufficient for RNMT recruitment to transcription initiation sites and that recruitment occurs in a DRB (5,6-dichloro-1-β-D-ribofuranosylbenzimidazole)-dependent manner. The RNMT-activating subunit, RAM (RNMT-activating miniprotein), is also recruited to transcription initiation sites via an interaction with RNMT. The RNMT N-terminal domain is required for transcript expression, translation and cell proliferation. Eukaryotic gene expression is dependent on the modification of the first transcribed nucleotide of pre-mRNA by the addition of the 7-methylguanosine cap. The cap protects transcripts from exonucleases and recruits complexes which mediate transcription elongation, processing and translation initiation. The cap is synthesized by a series of reactions which link 7-methylguanosine to the first transcribed nucleotide via a 5' to 5' triphosphate bridge. In mammals, cap synthesis is catalysed by the sequential action of RNGTT (RNA guanylyltransferase and 5'-phosphatase) and RNMT (RNA guanine-7 methyltransferase), enzymes recruited to RNA pol II (polymerase II) during the early stages of transcription. We recently discovered that the mammalian cap methyltransferase is a heterodimer consisting of RNMT and the RNMT-activating subunit RAM (RNMT-activating mini-protein). RAM activates and stabilizes RNMT and thus is critical for cellular cap methylation and cell viability. In the present study we report that RNMT interacts with the N-terminal 45 amino acids of RAM, a domain necessary and sufficient for maximal RNMT activation. In contrast, smaller components of this RAM domain are sufficient to stabilize RNMT. RAM functions in the nucleus and we report that nuclear import of RAM is dependent on PY nuclear localization signals and Kapβ2 (karyopherin β2) nuclear transport protein. We describe the synthesis and properties of five dinucleotide fluorescent cap analogues labelled at the ribose of the 7-methylguanosine moiety with either anthraniloyl (Ant) or N-methylanthraniloyl (Mant), which have been designed for the preparation of fluorescent mRNAs via transcription in vitro. Two of the analogues bear a methylene modification in the triphosphate bridge, providing resistance against either the Dcp2 or DcpS decapping enzymes. All these compounds were prepared by ZnCl2-mediated coupling of a nucleotide P-imidazolide with a fluorescently labelled mononucleotide. To evaluate the utility of these compounds for studying interactions with cap-binding proteins and cap-related cellular processes, both biological and spectroscopic features of those compounds were determined. The results indicate acceptable quantum yields of fluorescence, pH independence, environmental sensitivity, and photostability. The cap analogues are incorporated by RNA polymerase into mRNA transcripts that are efficiently translated in vitro. Transcripts containing fluorescent caps but unmodified in the triphosphate chain are hydrolysed by Dcp2 whereas those containing a α-β methylene modification are resistant. Model studies exploiting sensitivity of Mant to changes of local environment demonstrated utility of the synthesized compounds for studying cap-related proteins. Mammalian-cell messenger RNAs (mRNAs) are generated in the nucleus from precursor RNAs (pre-mRNAs, which often contain one or more introns) that are complexed with an array of incompletely inventoried proteins. During their biogenesis, pre-mRNAs and their derivative mRNAs are subject to extensive cis-modifications. These modifications promote the binding of distinct polypeptides that mediate a diverse array of functions needed for mRNA metabolism, including nuclear export, inspection by the nonsense-mediated mRNA decay (NMD) quality-control machinery, and synthesis of the encoded protein product. Ribonucleoprotein complex (RNP) remodeling through the loss and gain of protein constituents before and after pre-mRNA splicing, during mRNA export, and within the cytoplasm facilitates NMD, ensuring integrity of the transcriptome. Here we review the mRNP rearrangements that culminate in detection and elimination of faulty transcripts by mammalian-cell NMD.

What is HOCOMOCO?

HOCOMOCO is a comprehensive collection of human transcription factor binding sites models constructed by integration of binding sequences obtained by both low- and high-throughput methods. HOCOMOCO contains 426 systematically curated TFBS models for 401 human TFs, where 172 models are based on more than one data source.

In which condition was protein S100A7 originally identified?

Psoriasin (S100A7) was originally identified in psoriasis.

Human psoriasin (S100A7) has originally been described as a member of the family of S100 calcium-binding proteins which is overexpressed in patients suffering from psoriasis. The bovine homolog was first identified as a cow-derived respiratory allergen. As Escherichia coli mastitis is a common problem in dairy cattle, and human psoriasin was found to exhibit antimicrobial activity preferentially against E. coli, we examined whether the bovine mRNA is expressed in the mammary gland. To demonstrate the antimicrobial activity of bovine psoriasin, we isolated cDNA from the udder, cloned the bovine psoriasin gene in a bacterial expression vector, and the recombit protein was expressed in BL21 cells. The in vitro antibacterial activity was tested by performing microdilution susceptibility tests and radial diffusion assays with eight different bacterial strains, thereof three different E. coli strains, and one yeast. The antimicrobial activity of the recombit bovine psoriasin is comparable with human psoriasin and also limited to E. coli. Psoriasin appears to be a part of the local host defense mechanism in the udder, is a putative candidate for a cow-specific factor influencing mastitis susceptibility, and a possible alternative to conventional antibiotics. S100A7 (psoriasin) and S100A15 (koebnerisin) were first identified in inflamed psoriatic skin. They are of major interest because of their putative functional roles in innate immunity, epidermal cell maturation, and epithelial tumorigenesis. Human S100A7 and S100A15 have lately evolved by gene duplications within the epidermal differentiation complex (chromosome 1q21) during primate evolution forming a novel S100 subfamily. Therefore, S100A7 and S100A15 are almost identical in sequence (>90%) and are difficult to discriminate. Despite their high homology, S100A7 and S100A15 are distinct in tissue distribution, regulation, and function, and thus, exemplary for the diversity within the S100 family. Their different properties are compelling reasons to discriminate S100A7 (psoriasin) and S100A15 (koebnerisin) in epithelial homeostasis, inflammation, and cancer. Psoriasis is a common complex genetic disease characterized by hyperplasia and inflammation in the skin; however, the relative contributions of epidermal cells and the immune system to disease pathogenesis remain unclear. Linkage studies have defined a psoriasis susceptibility locus (PSORS4) on 1q21, the epidermal differentiation complex, which includes genes for small S100 calcium-binding proteins. These proteins are involved in extracellular and intracellular signaling during epithelial host defense, linking innate and adaptive immunity. Inflammation-prone psoriatic skin constitutively expresses elevated concentrations of S100A7 (psoriasin) and S100A15 (koebnerisin) in the epidermis. Here, we report that genetically modified mice expressing elevated amounts of doxycycline-regulated mS100a7a15 in skin keratinocytes demonstrated an exaggerated inflammatory response when challenged by exogenous stimuli such as abrasion (Koebner phenomenon). This immune response was characterized by immune cell infiltration and elevated concentrations of T helper 1 (T(H)1) and T(H)17 proinflammatory cytokines, which have been linked to the pathogenesis of psoriasis and were further amplified upon challenge. Both inflammation priming and amplification required mS100a7a15 binding to the receptor of advanced glycation end products (RAGE). mS100a7a15 potentiated inflammation by acting directly as a chemoattractant for leukocytes, further increasing the number of inflammatory cells infiltrating the skin. This study provides a pathogenetic psoriasis model using a psoriasis candidate gene to link the epidermis and innate immune system in inflammation priming, highlighting the S100A7A15-RAGE axis as a potential therapeutic target. Psoriasin (S100 A7) was discovered two decades ago as a protein abundantly expressed in psoriatic keratinocytes. Even though much scientific research has been carried out on the characterization of psoriasin, only recent studies point to an important role of psoriasin as an antimicrobial and immunomodulatory protein in skin and other epithelia. In this review, we provide an overview of the major findings in psoriasin research and discuss novel studies highlighting the role of psoriasin as an important effector molecule of the cutaneous barrier. PURPOSE: Psoriasin, originally isolated from psoriasis as an overexpressed molecule of unknown function, has recently been identified as a principal Escherichia coli-killing antimicrobial peptide of healthy skin. The purpose of this study was to investigate the expression and antimicrobial role of psoriasin at the ocular surface and in the lacrimal apparatus. METHODS: Different tissues of the lacrimal apparatus and ocular surface were systematically analyzed by means of RT-PCR, Western blot, and immunohistochemistry for their ability to express and produce psoriasin. The inducibility and regulation of psoriasin were studied in human corneal as well as conjunctival epithelial cell lines after challenge with ocular pathogens and proinflammatory cytokines. Real-time RT-PCR was performed to evaluate the expression and induction of psoriasin. In addition, tear fluid obtained from different healthy volunteers was examined by ELISA for its psoriasin concentration. RESULTS: RT-PCR and Western blot analyses revealed a constitutive expression of psoriasin in cornea, conjunctiva, nasolacrimal ducts, and lacrimal gland. Immunohistochemistry showed strong staining of meibomian glands for psoriasin. No induction of psoriasin was observed after stimulation with supernatants of E. coli, whereas supernatants of Staphylococcus aureus and Haemophilus influenzae significantly increased the psoriasin mRNA expression. Stimulation with IL-1β and VEGF also strongly increased psoriasin transcription. The highest amounts of psoriasin protein were detected in the tear fluid (~170 ng/mL) of healthy volunteers. CONCLUSIONS: The results suggest that psoriasin is produced by the structures of the ocular surface and is part of the innate immune system at the ocular surface and tear film. Psoriasin (S100A7), originally identified in psoriasis, is a calcium-binding protein belonging to the multigenic S100 family. In high-grade ductal carcinoma in situ, psoriasin was identified as one of the most abundant transcripts. We have previously shown that psoriasin was induced by reactive oxygen species (ROS). Moreover, the downregulation of psoriasin by short hairpin RNA (shRNA) led to the reduced expression of vascular endothelial growth factor (VEGF) and inhibited tumor growth in vivo. The aim of the present study was to investigate whether psoriasin could have direct effects on endothelial cells. In this study we demonstrated that psoriasin increased VEGF expression in mammary epithelial cells. The treatment of endothelial cells with recombit psoriasin increased proliferation comparable to that of recombit VEGF protein. No change in proliferation was seen when endothelial cells were infected with psoriasin-expressing adenoviruses, suggesting that the proliferative effect of psoriasin was mediated by a specific receptor. Treatment with sRAGE, targeting the receptor for advanced glycation end products (RAGE), thus inhibited endothelial cell proliferation and tube formation enhanced by recombit psoriasin. We showed that VEGF expression was not induced by hydrogen peroxide, when psoriasin was silenced by shRNA, which led to the hypothesis that psoriasin induces ROS. Indeed, psoriasin was shown to induce ROS in both endothelial and epithelial cells. Moreover, sRAGE inhibited the psoriasin-dependent generation of ROS in endothelial cells. Finally, treatment with antioxidant Bcl-2 protein abolished the effect of psoriasin on endothelial cell proliferation. Our data suggest that psoriasin expression in mammary epithelial cells leads to increased endothelial cell proliferation in a paracrine manner through RAGE. Psoriasin may therefore play a role in breast cancer progression by promoting oxidative stress response and angiogenesis.

Do proton pump inhibitors affect thyroxine absorption?

Proton-pump inhibitors, antacids and a long list of drugs may decrease thyroxine absorption. Patients with hypothyroidism and normal TSH values during LT4 replacement therapy may need additional thyroid function testing after treatment with PPIs and may need adjustment of their LT4 dose.

METHOD: In a randomized, double-blind, two-period crossover study, pantoprazole 40 mg or placebo were given orally to 12 male volunteers for 2 weeks each. There was a wash-out period of at least 1 week between the two treatment periods. The effects of pantoprazole or placebo on cortisol and testosterone (primary criteria), and tri-iodothyronine, thyroxine, thyroid-stimulating hormone, thyronine-binding protein, parathyroid hormone, insulin, glucagon, renin, aldosterone, follicle-stimulating hormone, luteotrophic hormone, prolactin and somatotrophic hormone were compared. In addition, intragastric 24-h pH, 24-h H(+)-activity, and volume of nocturnal gastric juice were determined by gastric aspiration technique. RESULTS: Pantoprazole did not influence plasma levels of testosterone, circadian cortisol concentrations or plasma cortisol levels after exogenous adrenocorticotropic hormone stimulation, as compared to placebo (P > 0.05, Koch's test). Furthermore, there were no clinically relevant changes with any of the other endocrine parameters. Pantoprazole significantly increased the median 24-h pH (group median 4.3 vs. 1.8; P < 0.001) and decreased 24-h H(+)-activity (4.0 vs. 22.6 mmol/L; P < 0.001). The volume of nocturnal gastric juice did not significantly differ between the two treatments. Pantoprazole was well tolerated and the frequency of adverse events was similar to placebo. No drug-related changes in laboratory values were observed. CONCLUSION: Pantoprazole did not influence endocrine function in healthy male volunteers during short-term treatment. OBJECTIVES: To develop a method for comparing the proportion of patients on any drug or group of drugs for individual GP patient panels in Ireland, taking account of the age and sex structure of the panel. DESIGN: Calculations based on prescribing data for the fourth-quarter of 1995 supplied by the Irish General Medical Services Payments Board for the Eastern Health Board area.Setting-Five hundred and fifty Irish general practices serving 355,000 persons entitled to free medical care under the General Medical Services Scheme in the Eastern Health Board area (28% of the population). MAIN OUTCOME MEASURES: Weightings for number of persons prescribed each of four drug groups, and all drugs combined, for 22 age/sex groupings, leading to a single age/sex adjusted prescribing index-the standardized prescribing ratio (SPR) for each GPs practice population. RESULTS: The SPRs showed a large amount of variation from the average figure of 100 for practices of 1000 or more patients for all drugs and for each of the four drug groups studied: all drugs 54-125, antibiotics 52-165, H(2) antagonists/proton pump inhibitors 38-197, antidepressants 13-213 and thyroxine 33-175. Practices with above average SPRs for all drugs, antibiotics and H(2) antagonists/proton pump inhibitors were significantly larger than those with below-average SPRs. Practices with below average SPRs for thyroxine were significantly larger than those with above-average SPRs. CONCLUSIONS: The SPR provides a useful age/sex adjusted method of comparing prescribing between GPs and it can be applied to any drug or group of drugs. BACKGROUND: Intensive care unit (ICU) admission may connote an elevated risk of unintentional chronic medication discontinuation because of its focus on acute illnesses and the multiple care transitions. OBJECTIVE: To determine the proportion of patients discharged from the ICU whose previously prescribed chronic medications were unintentionally discontinued during their hospitalization. DESIGN AND PARTICIPANTS: Hospital records of consecutive ICU discharges at 1 academic and 2 community hospitals in Toronto, Canada, throughout 2002 were reviewed. Eligible patients were prescribed at least 1 of 6 medication groups before hospitalization: (1) HMG co-A reductase inhibitors (statins); (2) antiplatelets/anticoagulants (aspirin, clopidogrel, ticlopidine, warfarin); (3) l-thyroxine; (4) non-prn inhalers (anticholinergic, beta-agonist, or steroid); (5) acid-suppressing drugs (H2 antagonists and proton pump inhibitors); and (6) allopurinol. MEASUREMENTS: Use of explicit criteria to assess the proportion of patients whose previously prescribed chronic medications were unintentionally discontinued at hospital discharge. RESULTS: A total of 1,402 charts were eligible for the study and 834 had prescriptions for at least 1 of the medication groups. Thirty-three percent (251/834) of patients had 1 or more of their chronic medications omitted at hospital discharge. Multivariable logistic regression analysis found that patients from the academic hospital (adjusted odds ratio [OR] = 0.70, 95% confidence interval [CI] 0.49 to 1.0) and those with medical diagnoses (adjusted OR=0.48, 95% CI 0.31 to 0.75) had a decreased risk for chronic medication discontinuation. CONCLUSIONS: Patients discharged from the ICU often leave the hospital without note of their previously prescribed chronic medications. Careful review of medication lists at ICU discharge could avoid potential adverse outcomes related to unintentional discontinuation of chronic medications at hospital discharge. 1. N Engl J Med. 2006 Sep 14;355(11):1177; author reply 1177. doi: 10.1056/NEJMc061447. PURPOSE: Patient co-payments for medicines subsidised under the Australian Pharmaceutical Benefits Scheme (PBS) increased by 24% in January 2005. We investigated whether this increase and two related co-payment changes were associated with changes in dispensings of selected subsidised medicines in Australia. METHOD: We analysed national aggregate monthly prescription dispensings for 17 medicine categories, selected to represent a range of treatments (e.g. for diabetes, cardiovascular diseases, gout). Trends in medication dispensings from January 2000 to December 2004 were compared with those from January 2005 to September 2007 using segmented regression analysis. RESULTS: Following the January 2005 increase in PBS co-payments, significant decrease in dispensing volumes were observed in 12 of the 17 medicine categories (range: 3.2-10.9%), namely anti-epileptics, anti-Parkinson's treatments, combination asthma medicines, eye-drops, glaucoma treatments, HmgCoA reductase inhibitors, insulin, muscle relaxants, non-aspirin antiplatelets, osteoporosis treatments, proton-pump inhibitors (PPIs) and thyroxine. The largest decrease was observed for medicines used in treating asymptomatic conditions or those with over-the-counter (OTC) substitutes. Decrease in dispensings to social security beneficiaries was consistently greater than for general beneficiaries following the co-payment changes (range: 1.8-9.4% greater, p = 0.028). CONCLUSIONS: The study findings suggest that recent increase in Australian PBS co-payments have had a significant effect on dispensings of prescription medicines. The results suggest large increase in co-payments impact on patients' ability to afford essential medicines. Of major concern is that, despite special subsidies for social security beneficiaries in the Australian system, the recent co-payment increase has particularly impacted on utilisation for this group. Food, dietary fibre and espresso coffee interfere with the absorption of levothyroxine. Malabsorptive disorders reported to affect the absorption of levothyroxine include coeliac disease, inflammatory bowel disease, lactose intolerance as well as Helicobacter pylori (H. pylori) infection and atrophic gastritis. Many commonly used drugs, such as bile acid sequestrants, ferrous sulphate, sucralfate, calcium carbonate, aluminium-containing antacids, phosphate binders, raloxifene and proton-pump inhibitors, have also been shown to interfere with the absorption of levothyroxine.

Is PER3 required for CHK2 activation in human cells?

Depletion of Per3 by siRNA almost completely abolished activation of checkpoint kinase 2 (Chk2) after inducing DNA damage in human cells.Per3, a circadian gene, is required for Chk2 activation in human cells.

What is the typical alteration of the thyroid profile metabolism early after coronary artery bypass graft surgery?

Low T3 Syndrome is the more frequent alteration of thyroid hormone profile early after coronary artery bypass graft surgery.

The effect of a surgical stress on serum TSH, T4, free T4, T3, rT3 and TBG was measured before, during and after a coronary bypass operation. Precautions were taken to age, sex, pre-operative nutritional state, anamnestic illness, pre- and post-operative medication. Compared to the pre-operative period TSH increased during operation and normalized at the first post-operative day, while only minor alterations for total and free serum T4 were observed. T3 and rT3 declined at the start of extracorporal circulation, T3 remained reduced during the post-operative period, while rT3 reached its pre-operative value at the first post-operative day. It is concluded that the coronary bypass operation evokes a rapid decline in T3, which is not normalized by the TSH induced response of the thyroid gland, while the post-operative period is characterized by a "low T3 state". The clinical relevance of this finding is discussed with respect to the cardiovascular and the nutritional state of the patients in the post-operative period. BACKGROUND: Cardiopulmonary bypass (CPB) is an established cause of nonthyroidal illness syndrome (NTIS). Off-pump coronary artery bypass (OPCAB) has been reported to be less invasive than coronary artery bypass grafting (CABG) with CPB. We prospectively evaluated thyroid metabolism in OPCAB patients. METHODS: We analyzed free thyroid hormones (FT3 and FT4), thyroid-stimulating hormone (TSH), and reverse T3 (rT3) in 20 consecutive patients undergoing CABG surgery. Nine patients underwent CABG with CPB, and 11 underwent OPCAB. Blood samples were taken on admission, on the day of surgery (7:30 AM), after sternotomy, at the end of the operation, and at 2, 6, 12, 24, 36, 48, 72, 96, 120, and 144 hours postoperatively. The concentrations of FT3, FT4, and TSH were determined on each sample. Reverse T3 concentration was measured in 10 patients up to 48 hours and at 144 hours postoperatively. RESULTS: Baseline, operative, and postoperative variables were similar in the two groups. FT3 concentration dropped significantly (p < 0.0001), reaching its lowest value 12 hours postoperatively. There were no significant differences between CPB and OPCAB patients. FT4 varied significantly in both groups (p < 0.0001), but remained in the normal range. TSH variation was not significant. rT3 concentration rose significantly (p = 0.0002) in both groups, peaking 24 hours after surgery. CONCLUSIONS. OPCAB induces a NTIS similar to that observed after CPB, probably due to the inhibition of T4 conversion to T3. This finding suggests that NTIS is a nonspecific response to stress. CPB should not be considered as the sole trigger of NTIS in cardiac surgical patients. OBJECTIVE: The authors sought to assess biochemical, hormonal and cellular repercussions from use of cardiopulmonary bypass (CPB) in coronary artery bypass graft (CABG) surgery. METHODS: Eighteen patients underwent on-pump CABG surgery. Mean time of CPB was 80.3 minutes. Hormonal, biochemical and cellular measurements were taken in some time points - preoperatively, immediately after coming off CPB, 24 and 48 hours postoperatively. Friedman and Wilcoxon tests were applied based on significance level of 5%. RESULTS: There was activation and significant elevation of total leukocytes and neutrophils count over CPB, remaining this way up to 48 hours postoperatively. Total platelets count, in turn, was marked by relevant reduction immediately after coming off CPB as well as in two postoperative time points. Serum levels of total proteins and albumin, immediately after coming off CPB and also in two postoperative time points, were significantly decreased comparing with preoperative status. There was remarkable reduction of total T3, free T3 and total T4 particularly up to first 24 hours postoperatively. CONCLUSION: In on-pump CABG surgery, inflammatory effects encompass activation of total leukocytes, neutrophils and platelets, reduction of serum level of total proteins and albumin and decreased thyroid hormones levels, especially within first postoperative 24 hours.

Which proteins are involved in actin bundling and filopodia formation and function?

A number of proteins have been found to regulate F-actin bundling and enhance filopodia formation and motility. Among these are Cysteine-rich protein 1 (CRP1), Fascin, Macrophage actin-associated tyrosine phosphorylated protein (MAYP/PSTPIP2), Insulin receptor tyrosine kinase substrate p53 (IRSp53), Missing in metastasis protein (MIM), Eps8, Diaphanous-related formin (dDia2) and Vasodilator-stimulated phosphoprotein (VASP).

Growth cones at the distal tips of growing nerve axons contain bundles of actin filaments distributed throughout the lamellipodium and that project into filopodia. The regulation of actin bundling by specific actin binding proteins is likely to play an important role in many growth cone behaviors. Although the actin binding protein, fascin, has been localized in growth cones, little information is available on its functional significance. We used the large growth cones of the snail Helisoma to determine whether fascin was involved in temporal changes in actin filaments during growth cone morphogenesis. Fascin localized to radially oriented actin bundles in lamellipodia (ribs) and filopodia. Using a fascin antibody and a GFP fascin construct, we found that fascin incorporated into actin bundles from the beginning of growth cone formation at the cut end of axons. Fascin associated with most of the actin bundle except the proximal 6--12% adjacent to the central domain, which is the region associated with actin disassembly. Later, during growth cone morphogenesis when actin ribs shortened, the proximal fascin-free zone of bundles increased, but fascin was retained in the distal, filopodial portion of bundles. Treatment with tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA), which phosphorylates fascin and decreases its affinity for actin, resulted in loss of all actin bundles from growth cones. Our findings suggest that fascin may be particularly important for the linear structure and dynamics of filopodia and for lamellipodial rib dynamics by regulating filament organization in bundles. Insulin receptor tyrosine kinase substrate p53 (IRSp53) has been identified as an SH3 domain-containing adaptor that links Rac1 with a Wiskott-Aldrich syndrome family verprolin-homologous protein 2 (WAVE2) to induce lamellipodia or Cdc42 with Mena to induce filopodia. The recruitment of these SH3-binding partners by IRSp53 is thought to be crucial for F-actin rearrangements. Here, we show that the N-terminal predicted helical stretch of 250 amino acids of IRSp53 is an evolutionarily conserved F-actin bundling domain involved in filopodium formation. Five proteins including IRSp53 and missing in metastasis (MIM) protein share this unique domain and are highly conserved in vertebrates. We named the conserved domain IRSp53/MIM homology domain (IMD). The IMD has domain relatives in invertebrates but does not show obvious homology to any known actin interacting proteins. The IMD alone, derived from either IRSp53 or MIM, induced filopodia in HeLa cells and the formation of tightly packed parallel F-actin bundles in vitro. These results suggest that IRSp53 and MIM belong to a novel actin bundling protein family. Furthermore, we found that filopodium-inducing IMD activity in the full-length IRSp53 was regulated by active Cdc42 and Rac1. The SH3 domain was not necessary for IMD-induced filopodium formation. Our results indicate that IRSp53, when activated by small GTPases, participates in F-actin reorganization not only in an SH3-dependent manner but also in a manner dependent on the activity of the IMD. Macrophage actin-associated tyrosine phosphorylated protein (MAYP) belongs to the Pombe Cdc15 homology (PCH) family of proteins involved in the regulation of actin-based functions including cell adhesion and motility. In mouse macrophages, MAYP is tyrosine phosphorylated after activation of the colony-stimulating factor-1 receptor (CSF-1R), which also induces actin reorganization, membrane ruffling, cell spreading, polarization, and migration. Because MAYP associates with F-actin, we investigated the function of MAYP in regulating actin organization in macrophages. Overexpression of MAYP decreased CSF-1-induced membrane ruffling and increased filopodia formation, motility and CSF-1-mediated chemotaxis. The opposite phenotype was observed with reduced expression of MAYP, indicating that MAYP is a negative regulator of CSF-1-induced membrane ruffling and positively regulates formation of filopodia and directional migration. Overexpression of MAYP led to a reduction in total macrophage F-actin content but was associated with increased actin bundling. Consistent with this, purified MAYP bundled F-actin and regulated its turnover in vitro. In addition, MAYP colocalized with cortical and filopodial F-actin in vivo. Because filopodia are postulated to increase directional motility by acting as environmental sensors, the MAYP-stimulated increase in directional movement may be at least partly explained by enhancement of filopodia formation. Filopodia are highly dynamic finger-like cell protrusions filled with parallel bundles of actin filaments. Previously we have shown that Diaphanous-related formin dDia2 is involved in the formation of filopodia. Another key player for the formation of filopodia across many species is vasodilator-stimulated phosphoprotein (VASP). It has been proposed that the essential role of VASP for formation of filopodia is its competition with capping proteins for filament barbed-end interaction. To better understand the function of VASP in filopodium formation, we analyzed the in vitro and in vivo properties of Dictyostelium VASP (DdVASP) and extended our findings to human VASP. Recombit VASP from both species nucleated and bundled actin filaments, but did not compete with capping proteins or block depolymerization from barbed ends. Together with the finding that DdVASP binds to the FH2 domain of dDia2, these data indicate that the crucial role of VASP in filopodium formation is different from uncapping of actin filaments. To identify the activity of DdVASP required in this process, rescue experiments of DdVASP-null cells with mutant DdVASP constructs were performed. Only WT DdVASP, but not a mutant lacking the F-actin bundling activity, could rescue the ability of these cells to form WT-like filopodia. Our data suggest that DdVASP is complexed with dDia2 in filopodial tips and support formin-mediated filament elongation by bundling nascent actin filaments. Actin-crosslinking proteins organize actin into highly dynamic and architecturally diverse subcellular scaffolds that orchestrate a variety of mechanical processes, including lamellipodial and filopodial protrusions in motile cells. How signalling pathways control and coordinate the activity of these crosslinkers is poorly defined. IRSp53, a multi-domain protein that can associate with the Rho-GTPases Rac and Cdc42, participates in these processes mainly through its amino-terminal IMD (IRSp53 and MIM domain). The isolated IMD has actin-bundling activity in vitro and is sufficient to induce filopodia in vivo. However, the manner of regulation of this activity in the full-length protein remains largely unknown. Eps8 is involved in actin dynamics through its actin barbed-ends capping activity and its ability to modulate Rac activity. Moreover, Eps8 binds to IRSp53. Here, we describe a novel actin crosslinking activity of Eps8. Additionally, Eps8 activates and synergizes with IRSp53 in mediating actin bundling in vitro, enhancing IRSp53-dependent membrane extensions in vivo. Cdc42 binds to and controls the cellular distribution of the IRSp53-Eps8 complex, supporting the existence of a Cdc42-IRSp53-Eps8 signalling pathway. Consistently, Cdc42-induced filopodia are inhibited following individual removal of either IRSp53 or Eps8. Collectively, these results support a model whereby the synergic bundling activity of the IRSp53-Eps8 complex, regulated by Cdc42, contributes to the generation of actin bundles, thus promoting filopodial protrusions. Fascin is an actin-bundling protein involved in filopodia assembly and cancer invasion and metastasis of multiple epithelial cancer types. Fascin forms stable actin bundles with slow dissociation kinetics in vitro and is regulated by phosphorylation of serine 39 by protein kinase C (PKC). Cancer cells use invasive finger-like protrusions termed invadopodia to invade into and degrade extracellular matrix. Invadopodia have highly dynamic actin that is assembled by both Arp2/3 complex and formins; they also contain components of membrane trafficking machinery such as dynamin and cortactin and have been compared with focal adhesions and podosomes. We show that fascin is an integral component of invadopodia and that it is important for the stability of actin in invadopodia. The phosphorylation state of fascin at S39, a PKC site, contributes to its regulation at invadopodia. We further implicate fascin in invasive migration into collagen I-Matrigel gels and particularly in cell types that use an elongated mesenchymal type of motility in 3D. We provide a potential molecular mechanism for how fascin increases the invasiveness of cancer cells, and we compare invadopodia with invasive filopod-like structures in 3D. Slug, a member of the Snail family of transcription factors, has a crucial role in the regulation of epithelial-mesenchymal transition (EMT) by suppressing several epithelial markers and adhesion molecules, including E-cadherin. A recent study demonstrated that no relationship exists between Slug and E-cadherin in pancreatic cancer. Another study showed that in maligt mesothelioma effusions Slug was associated with matrix metalloproteinase (MMP) expression, but that there was no association with E-cadherin. F-ascin is an actin-bundling protein involved in filopodia assembly and cancer invasion and metastasis of multiple epithelial cancer types. In this study, we investigated Slug, E-cadherin, and MMP-9 expression using immunohistochemistry in 60 patients with pancreatic cancer and their correlation with carcinoma invasion and metastasis. Additionally, we observed the effects of Slug on invasion and metastasis in the pancreatic cancer cell line PANC-1. Alterations in Slug, MMP-9, and E-cadherin were determined by RT-PCR, western blot, and immunohistochemistry. Alterations in MMP-9 and F-actin cytoskeleton were determined by immunofluorescence staining, flow cytometry (FCM), or gelatin zymography. Slug, E-cadherin, and MMP-9 expression in pancreatic cancer was significantly associated with lymph node metastases and we found a significant correlation between Slug and MMP-9 expression; however, no significant correlation was observed between Slug and E-cadherin expression. Slug transfection significantly increased invasion and metastasis in PANC-1 cells and orthotopic tumor of mouse in vivo, and significantly upregulated and activated MMP-9; however, there was no effect on E-cadherin expression. Slug promoted the formation of lamelliopodia or filopodia in PANC-1 cells. The intracellular F-actin and MMP-9 was increased and relocated to the front of the extending pseudopodia from the perinuclear pool in Slug-transfected PANC-1 cells. These results suggest that Slug promotes migration and invasion of PANC-1 cells, which may correlate with the reorganization of MMP-9 and remodeling of the F-actin cytoskeleton, but not with E-cadherin expression. The cysteine-rich protein (CRP) family is a subgroup of LIM domain proteins. CRP1, which cross-links actin filaments to make actin bundles, is the only CRP family member expressed in the CNS with little known about its function in nerve cells. Here, we report that CRP1 colocalizes with actin in the filopodia of growth cones in cultured rat hippocampal neurons. Knockdown of CRP1 expression by short hairpin RNA interference results in inhibition of filopodia formation and dendritic growth in neurons. Overexpression of CRP1 increases filopodia formation and neurite branching, which require its actin-bundling activity. Expression of CRP1 with a constitutively active form of Cdc42, a GTPase involved in filopodia formation, increases filopodia formation in COS-7 cells, suggesting cooperation between the two proteins. Moreover, we demonstrate that neuronal activity upregulates CRP1 expression in hippocampal neurons via Ca²⁺ influx after depolarization. Ca²⁺/calmodulin-dependent protein kinase IV (CaMKIV) and cAMP response element binding protein mediate the Ca²⁺-induced upregulation of CRP1 expression. Furthermore, CRP1 is required for the dendritic growth induced by Ca²⁺ influx or CaMKIV. Together, these data are the first to demonstrate a role for CRP1 in dendritic growth.

What does the SAGA complex acronym stands for?

SAGA stands for Spt-Ada-Gcn5-acetyltransferase (SAGA)

The molecular organization of the yeast transcriptional coactivator Spt-Ada-Gcn5 acetyltransferase (SAGA) was analyzed by single-particle electron microscopy. Complete or partial deletion of the Sgf73 subunit disconnects the deubiquitination (DUB) module from SAGA and favors in our conditions the cleavage of the C-terminal ends of the Spt7 subunit and the loss of the Spt8 subunit. The structural comparison of the wild-type SAGA with two deletion mutants positioned the DUB module and enabled the fitting of the available atomic models. The localization of the DUB module close to Gcn5 defines a chromatin-binding interface within SAGA, which could be demonstrated by the binding of nucleosome core particles. The TATA-box binding protein (TBP)-interacting subunit Spt8 was found to be located close to the DUB but in a different domain than Spt3, also known to contact TBP. A flexible protein arm brings both subunits close enough to interact simultaneously with TBP. NuA4 (nucleosome acetyltransferase of H4) promotes transcriptional initiation of TFIID (a complex of TBP and TBP-associated factors [TAFs])-dependent ribosomal protein genes involved in ribosome biogenesis. However, it is not clearly understood how NuA4 regulates the transcription of ribosomal protein genes. Here, we show that NuA4 is recruited to the promoters of ribosomal protein genes, such as RPS5, RPL2B, and RPS11B, for TFIID recruitment to initiate transcription, and the recruitment of NuA4 to these promoters is impaired in the absence of its Eaf1p component. Intriguingly, impaired NuA4 recruitment in a Δeaf1 strain depletes recruitment of TFIID (a TAF-dependent form of TBP) but not the TAF-independent form of TBP to the promoters of ribosomal protein genes. However, in the absence of NuA4, SAGA (Spt-Ada-Gcn5-acetyltransferase) is involved in targeting the TAF-independent form of TBP to the promoters of ribosomal protein genes for transcriptional initiation. Thus, NuA4 plays an important role in targeting TFIID to the promoters of ribosomal protein genes for transcriptional initiation in vivo. Such a function is mediated via its targeted histone acetyltransferase activity. In the absence of NuA4, ribosomal protein genes lose TFIID dependency and become SAGA dependent for transcriptional initiation. Collectively, these results provide significant insights into the regulation of ribosomal protein gene expression and, hence, ribosome biogenesis and functions. Protein complexes involved in epigenetic regulation of transcription have evolved as molecular strategies to face environmental stress in plants. SAGA (Spt-Ada-Gcn5 Acetyltransferase) is a transcriptional co-activator complex that regulates numerous cellular processes through the coordination of multiple post-translational histone modifications, including acetylation, deubiquitination, and chromatin recognition. The diverse functions of the SAGA complex involve distinct modules that are highly conserved between yeast, flies, and mammals. In this review, the composition of the SAGA complex in plants is described and its role in gene expression regulation under stress conditions summarized. Some of these proteins are likely involved in the regulation of the inducible expression of genes under light, cold, drought, salt, and iron stress, although the functions of several of its components remain unknown.

What is the result of the interaction between TSC1 and PLK1?

Phosphorylated TSC1 (hamartin) interacts with Plk1 independent of TSC2 (tuberin), with all three proteins present in a complex, and negatively regulates the protein levels of Plk1, to control centrosome duplication.

Tuberous sclerosis complex (TSC) is a tumor suppressor gene syndrome caused by mutations in TSC1 and TSC2. Hamartin and tuberin, the products of TSC1 and TSC2, respectively, form heterodimers and inhibit the mammalian target of rapamycin. Previously, we have shown that hamartin is phosphorylated by CDC2/cyclin B1 during the G(2)/M phase of the cell cycle. Here, we report that hamartin is localized to the centrosome and that phosphorylated hamartin and phosphorylated tuberin co-immunoprecipitate with the mitotic kinase Plk1. Plk1 interacts with the N-terminus of hamartin (amino acids 1-880), which contains two potential Plk1-binding sites (T310 and S332). Phosphorylated hamartin interacts with Plk1 independent of tuberin with all three proteins present in a complex. A non-phosphorylatable hamartin mutant with an alanine substitution at residue T310 does not interact with Plk1, whereas a non-phosphorylatable hamartin mutant at residue S332 in conjunction with alanine mutations at the other CDC2/cyclin B1 sites (T417, S584 and T1047) does not impact hamartin binding to Plk1. Hamartin negatively regulates the protein levels of Plk1. Finally, Tsc1(-/-) mouse embryonic fibroblasts (MEFs) have increased number of centrosomes and increased DNA content, compared to Tsc1(+/+) cells. Both phenotypes are rescued after pre-treatment with the mTOR inhibitor rapamycin. RNAi inhibition of Plk1 in Tsc1(-/-) MEFs failed to rescue the increased centrosome number phenotype. These data reveal a novel subcellular localization for hamartin and a novel interaction partner for the hamartin/tuberin complex and implicate hamartin and mTOR in the regulation of centrosome duplication.

What are the characteristics of the "Universal Proteomics Standard 2" (UPS2)?

The UPS2 proteomic dynamic range standard was introduced by the Association of Biomolecular Resource Facilities Proteomics Standards Research Group in 2006 and it has a dynamic range of 5 orders of magnitude.

Proteome scale absolute quantification is fundamental for the quantitative understanding of an organism. The unsatisfactory accuracy for protein abundance estimation of current algorithms has been partially improved by the Absolute Protein EXpression profiling (APEX) algorithm, which implements the prior expectations of peptides' appearances in the calculation of protein abundances. However, the abundance feature (AF) in APEX is the spectral count (SC); an AF suffers from a narrow dynamic range, thus, unsatisfactory accuracy. Therefore, we adopted another tandem mass spectrometric (MS/MS) level AF called Summed MS/MS Total ion current (SMT), which cumulates the MS/MS fragment intensities rather than simply counting the MS/MS spectra, to surmount this particular deficiency. The combination of APEX and SMT (abbreviated as APEX-SMT) is capable of improving the accuracy of absolute quantification by reducing the average relative deviation by ~55-85% compared to that of APEX, through a series of tests on the Universal Proteomics Standard sample with a dynamic range of 5 orders of magnitude (UPS2). The algorithm could also be used for relative quantification. When applied to the relative quantification of a publicly available benchmark dataset, APEX-SMT could provide comparable accuracy to APEX. All these results suggest that APEX-SMT is a promising alternative to APEX for proteome quantification.

Which polyQ tract protein is linked to Spinocerebellar Ataxia type 2?

Ataxin-2 is an evolutionarily conserved protein first identified in humans as responsible for spinocerebellar ataxia type 2 (SCA2). The molecular basis of SCA2 is the expansion of a polyglutamine tract in Ataxin-2, encoding a Lsm domain that may bind RNA and a PAM2 motif that enables interaction with the poly (A) binding protein.

Which are the smallest known subviral pathogens of plants?

Contrary to earlier beliefs, viruses are not the smallest causative agents of infectious diseases. Single-stranded RNAs as small as 246 nucleotides exist in certain higher plants and cause more than a dozen crop diseases. These RNAs have been termed viroids. Viroids are plant subviral pathogens whose genomes are constituted by a single-stranded and covalently closed small RNA molecule that does not encode for any protein.

Contrary to earlier beliefs, viruses are not the smallest causative agents of infectious diseases. Single-stranded RNAs as small as 246 nucleotides exist in certain higher plants and cause more than a dozen crop diseases. These RNAs have been termed viroids. Despite their extremely limited information content, viroids replicate autonomously in susceptible cells--that is, they do not require helper functions from simultaneously replicating conventional viruses. Viroids are covalently closed circular molecules with a characteristic rodlike secondary structure in which short helical regions are interrupted by internal and bulge loops. Viroids are not translated; they are replicated by a host enzyme (or enzymes) (probably RNA polymerase II) via oligomeric RNA intermediates by a rolling circle mechanism. Viroidlike satellite RNAs resemble viroids in size and molecular structure, but are found within the capsids of specific helper viruses on which they depend for their own replication. These RNAs are of great interest to molecular biology for at least two reasons: 1) they are the smallest and simplest replicating molecules known, and 2) they may represent living fossils of precellular evolution in a hypothetical RNA world. Research during the last 15 years has conclusively shown that viroids are not only fundamentally different from viruses at the molecular level, but that they are most likely not directly related to viruses in an evolutionary sense. Today, viroids are among the most thoroughly studied biological macromolecules. Their molecular structures have been elucidated to a large extent, but much needs to be learned regarding the correlation between molecular structure and biological function. The availability of the tools of recombit DNA technology in viroid research promises rapid progress in these areas of inquiry. Viroids, subviral pathogens of plants, are composed of a single-stranded circular RNA of 246-399 nucleotides. Within the 27 viroids sequenced, avocado sunblotch, peach latent mosaic and chrysanthemum chlorotic mottle viroids (ASBVd, PLMVd and CChMVd, respectively) can form hammerhead structures in both of their polarity strands. These ribozymes mediate self-cleavage of the oligomeric RNAs generated in the replication through a rolling circle mechanism, whose two other steps are catalyzed by an RNA polymerase and an RNA ligase. ASBVd, and presumably PLMVd and CChMVd, replicate and accumulate in the chloroplast, whereas typical viroids replicate and accumulate in the nucleus. PLMVd and CChMVd do not adopt a rod-like or quasi rod-like secondary structure as typical viroids do but have a highly branched conformation. A pathogenicity determit has been mapped in a defined region of the CChMVd molecule. Viroids are small, circular, single-stranded RNA molecules that cause several infectious plant diseases. Viroids do not encode any pathogen-specific peptides but nonetheless, the subviral pathogens replicate autonomously and spread in the plant by recruiting host proteins via functional motifs encoded in their RNA genome. During the past couple of years, considerable progress has been made towards comprehending how viroids interact with their hosts. Here, we summarize recent findings on the structure-function relationships of viroids, their strategies and mechanisms of replication and trafficking, and the identification and characterization of interacting host proteins. We also describe the impact of the RNA silencing machinery of plants on viroid RNAs and how this has started to influence our models of viroid replication and pathogenicity. BACKGROUND: Viroids, satellite RNAs, satellites viruses and the human hepatitis delta virus form the 'brotherhood' of the smallest known infectious RNA agents, known as the subviral RNAs. For most of these species, it is generally accepted that characteristics such as cell movement, replication, host specificity and pathogenicity are encoded in their RNA sequences and their resulting RNA structures. Although many sequences are indexed in publicly available databases, these sequence annotation databases do not provide the advanced searches and data manipulation capability for identifying and characterizing subviral RNA motifs. DESCRIPTION: The Subviral RNA database is a web-based environment that facilitates the research and analysis of viroids, satellite RNAs, satellites viruses, the human hepatitis delta virus, and related RNA sequences. It integrates a large number of Subviral RNA sequences, their respective RNA motifs, analysis tools, related publication links and additional pertinent information (ex. links, conferences, announcements), allowing users to efficiently retrieve and analyze relevant information about these small RNA agents. CONCLUSION: With its design, the Subviral RNA Database could be considered as a fundamental building block for the study of these related RNAs. It is freely available via a web browser at the URL: http://subviral.med.uottawa.ca. Viroids are plant subviral pathogens whose genomes are constituted by a single-stranded and covalently closed small RNA molecule that does not encode for any protein. Despite this genomic simplicity, they are able of inducing devastating symptoms in susceptible plants. Most of the 29 described viroid species fold into a rodlike or quasi-rodlike structure, whereas a few of them fold as branched structures. The shape of these RNA structures is perhaps one of the most characteristic properties of viroids and sometimes is considered their only phenotype. Here we use RNA thermodynamic secondary structure prediction algorithms to compare the mutational robustness of all viroid species. After characterizing the statistical properties of the distribution of mutational effects on structure stability and the wideness of neutral neighborhood for each viroid species, we show an evolutionary trend toward increased structural robustness during viroid radiation, giving support to the adaptive value of robustness. Differences in robustness among the 2 viroid families can be explained by the larger fragility of branched structures compared with the rodlike ones. We also show that genomic redundancy can contribute to the robustness of these simple RNA genomes. A common challenge in pathogen discovery by deep sequencing approaches is to recognize viral or subviral pathogens in samples of diseased tissue that share no significant homology with a known pathogen. Here we report a homology-independent approach for discovering viroids, a distinct class of free circular RNA subviral pathogens that encode no protein and are known to infect plants only. Our approach involves analyzing the sequences of the total small RNAs of the infected plants obtained by deep sequencing with a unique computational algorithm, progressive filtering of overlapping small RNAs (PFOR). Viroid infection triggers production of viroid-derived overlapping siRNAs that cover the entire genome with high densities. PFOR retains viroid-specific siRNAs for genome assembly by progressively eliminating nonoverlapping small RNAs and those that overlap but cannot be assembled into a direct repeat RNA, which is synthesized from circular or multimeric repeated-sequence templates during viroid replication. We show that viroids from the two known families are readily identified and their full-length sequences assembled by PFOR from small RNAs sequenced from infected plants. PFOR analysis of a grapevine library further identified a viroid-like circular RNA 375 nt long that shared no significant sequence homology with known molecules and encoded active hammerhead ribozymes in RNAs of both plus and minus polarities, which presumably self-cleave to release monomer from multimeric replicative intermediates. A potential application of the homology-independent approach for viroid discovery in plant and animal species where RNA replication triggers the biogenesis of siRNAs is discussed. Replicating circular RNAs are independent plant pathogens known as viroids, or act to modulate the pathogenesis of plant and animal viruses as their satellite RNAs. The rate of discovery of these subviral pathogens was low over the past 40 years because the classical approaches are technical demanding and time-consuming. We previously described an approach for homology-independent discovery of replicating circular RNAs by analysing the total small RNA populations from samples of diseased tissues with a computational program known as progressive filtering of overlapping small RNAs (PFOR). However, PFOR written in PERL language is extremely slow and is unable to discover those subviral pathogens that do not trigger in vivo accumulation of extensively overlapping small RNAs. Moreover, PFOR is yet to identify a new viroid capable of initiating independent infection. Here we report the development of PFOR2 that adopted parallel programming in the C++ language and was 3 to 8 times faster than PFOR. A new computational program was further developed and incorporated into PFOR2 to allow the identification of circular RNAs by deep sequencing of long RNAs instead of small RNAs. PFOR2 analysis of the small RNA libraries from grapevine and apple plants led to the discovery of Grapevine latent viroid (GLVd) and Apple hammerhead viroid-like RNA (AHVd-like RNA), respectively. GLVd was proposed as a new species in the genus Apscaviroid, because it contained the typical structural elements found in this group of viroids and initiated independent infection in grapevine seedlings. AHVd-like RNA encoded a biologically active hammerhead ribozyme in both polarities, and was not specifically associated with any of the viruses found in apple plants. We propose that these computational algorithms have the potential to discover novel circular RNAs in plants, invertebrates and vertebrates regardless of whether they replicate and/or induce the in vivo accumulation of small RNAs. Since the discovery of non-coding, small, highly structured, satellite RNAs (satRNAs) and viroids as subviral pathogens of plants , have been of great interest to molecular biologists as possible living fossils of pre-cellular evolution in an RNA world. Despite extensive studies performed in the last four decades, there is still mystery surrounding the origin and evolutionary relationship between these subviral pathogens. Recent technical advances revealed some commonly shared replication features between these two subviral pathogens. In this review, we discuss our current perception of replication and evolutionary origin of these petite RNA pathogens.

What causes Katayama Fever?

Katayama fever is an acute clinical condition characterised by high fever, dry cough and general malaise occurring during early Schistosoma spp. infection.

Katayama fever or acute schistosomiasis probably occurs more commonly than is recorded. Interviews with a 3-man scuba diving team who had had contact with a large dam in an endemic area of the eastern Transvaal Lowveld at the same time and contact area on the same day during late summer of 1986 are discussed. Two, who had not previously been exposed to infected water, presented with Katayama fever, due to Schistosoma mansoni infection, 21 days after contact and it took 30-36 months for them to recover fully after several treatments. The third patient, a keen water-sportsman and resident in the endemic area for a period of 10 years, presented with a mild infection, probably due to acquired immunity initiated during previous contacts with infected water; he took about a year to recover. The pathogenesis, clinical features, diagnosis and treatment of the 3 cases are described in the light of recent observations made elsewhere on Katayama fever cases and the effects of chemotherapy on the course of illness. The necessity of obtaining basic information on the travel and water-contact activities of patients in order to make a diagnosis is emphasised. A 19-year-old male university student of West Indian origin presented with fever, rigor, watery diarrhoea and noted intermittent generalised giant urticarial wheals of 2 weeks' duration. He swam in Lake Victoria, Uganda, 6 weeks previously and developed a swimmers' itch. Ova of Schistosoma mansoni was demonstrated by the formol-ether concentration method of the faeces. An initial single dose (40 mg/kg) of praziquantel with prednisolone 40 mg once daily for 5 days was given with no clinical deterioration of his condition. It is therefore safe and beneficial to give corticosteroid with chemotherapy in acute schistosomiasis (Katayama fever). The best therapeutic approach to acute schistosomiasis (Katayama fever) is still unsettled. In this paper we report a synergistic effect between schistosomicides and steroids in the treatment of the early stages of Schistosoma mansoni infection in the mouse. CBA mice infected with 150 S. mansoni cercariae were treated with oxamniquine or praziquantel and dexamethasone or prednisolone. The rate of parasite egg excretion by treated mice and appropriate controls was monitored, and the mice were perfused 43 d after infection for estimation of worm burdens and tissue egg densities. Mice treated with schistosomicides alone or with schistosomicides plus steroids had worm burdens of similar size. Significant reductions in egg counts were, however, recorded in faeces, and in the intestines and livers (with consequent reduction in liver pathology), of mice treated with schistosomicide and steroid, when compared to mice treated with schistosomicide alone or steroid alone. The apparent inhibition of fecundity of S. mansoni by combining these drugs has clear implications for treatment of the Katayama syndrome. Acute schistosomiasis (Katayama fever) may present with a broad spectrum of symptoms three to six weeks after primary infection by Schistosoma (S) mansoni, S. japonicum or, more rarely, S. haematobium. The acute phase of schistosomiasis is frequently confused with other feverish diseases. It occurs almost exclusively in nonimmune visitors to endemic areas. We describe seven cases of acute S. mansoni infection. The pathogenesis, clinical features, diagnosis and treatment are briefly discussed. Katayama fever should be considered in patients returning from endemic areas with fever and eosinophilia. Clinically normal, but potentially exposed travel companions should be examined as well. Early diagnosis and treatment may be important in preventing the infection's serious sequelae of the infection. OBJECTIVES: To investigate the characteristics of imported Katayama fever (acute schistosomiasis) as well as evolution and outcome under treatment. METHODS: Between April 2000 and September 2004, we included prospectively all patients with confirmed diagnosis of Katayama fever. Follow-up was maintained at least until 6 months after symptoms resolved. Praziquantel (PZQ) was given as soon as the diagnosis was probable, most of the time with steroids. RESULTS: Twenty-three patients were diagnosed with Katayama fever by Schistosoma egg detection and/or by seroconversion. Clinical features were non-specific, with mainly respiratory and/or gastrointestinal symptoms. Diagnosis was confirmed at presentation in 17/23 (74%) patients, of whom 15 by serology. Immediate clinical exacerbation occurred in five of nine patients not given steroids concomitantly with PZQ. After initial resolution, fever recurred in five (22%) patients. When compiling initial and recurrent episodes (n=28), respiratory symptoms tended to occur at an earlier stage after exposure, while abdominal complaints were more frequent later. All patients were completely cured, sometimes after repeated treatments. CONCLUSIONS: Clinical presentation of Katayama fever is non-specific and involves respiratory and abdominal symptoms. Recurrence of fever is not unusual despite anti-helminthic treatment. Optimal therapeutic strategy remains to be defined to prevent recurrence. A 35-year-old man presented with fever and severe urticaria after visiting Uganda. His symptoms were caused by acute invasive schistosomiasis, also known as Katayama fever. Schistosomiasis is a helminthic infection that is endemic in tropical and subtropical regions. Pulmonary involvement can be divided into two categories: acute or chronic compromise. Chronic and recurrent infection develops in persons living or travelling in endemic areas. In the lungs, granuloma formation and fibrosis around the schistosome eggs retained in the pulmonary vasculature may result in obliterative arteriolitis and pulmonary hypertension leading to cor pulmonale. Acute schistosomiasis is associated with primary exposure and is commonly seen in nonimmune travelers. The common CT findings in acute pulmonary schistosomiasis are small pulmonary nodules ranging from 2 to 15 mm and larger nodules with ground glass-opacity halo. Katayama fever is a severe clinical manifestation of acute involvement. We present a case of pulmonary involvement in schistosomiasis and provide a discussion about typical imaging findings in the acute and chronic form. Fever is the most common reason that children and infants are brought to emergency departments. Emergency physicians face the challenge of quickly distinguishing benign from life-threatening conditions. The management of fever in children is guided by the patient's age, immunization status, and immune status as well as the results of a careful physical examination and appropriate laboratory tests and radiographic views. In this article, the evaluation and treatment of children with fevers of known and unknown origin are described. Causes of common and dangerous conditions that include fever in their manifestation are also discussed. Schistosomiasis is the second most common socio-economically devastating parasitic disease after malaria, affecting about 240 million residents of developing countries. In Africa, it predomitly manifests as urogenital disease, and the main infective agent is Schistosoma hematobium. Endemicity is propagated by poor socio-economic status and environmental degradation due to rapid urbanization. Recreational swimming is a potent medium for the spread of disease in children and adolescents. Most affected individuals are asymptomatic. The male and female worms are equipped with an extraordinary capacity for immune evasion and are able to co-habit for several decades within the pelvic venous plexus. Eggs deposited in the bladder wall resist elimination by type 1 T lymphocytes. Instead, they are sustained by pro-fibrogenic encapsulation (as modulated by type 2 helper cells). Progressive bladder disease results in obstructive uropathy and predisposes to (mostly) squamous cell carcinoma. Schistosomal glomerulopathy manifests as a clinical spectrum of asymptomatic proteinuria, nephrosis and/or nephritic syndrome. Findings on renal biopsy may be influenced by co-morbidity with Salmonella bacteria, amyloidosis and hepatitis C infection. Potentially fatal Katayama fever and spinal radiculopathy may ensue in tourists visiting an endemic zone. Early detection by urine microscopy is hampered by low urinary excretion rates of the parasite eggs. Although useful in travelers with newly acquired disease, the results of the serological antibody assay may be false positive in residents of an endemic zone. Cystoscopy, however, may be invaluable. Due to its safety, effectiveness and once-daily dosing, praziquantel is the drug of choice. An integrated approach that includes mass chemotherapy, environmental health programs and public health education is the most cost-effective preventive strategy. The gold standard for laboratory diagnosis of schistosomiasis is the presence of typical eggs in stool or urine. The laboratory diagnosis of schistosomiasis and Katayama syndrome in returning travellers is difficult because the number of excreted eggs is often very limited. In early infections and in patients with only a few contacts with contaminated water, the total number of parasites, migrating larvae or schistosomulae, and adult worms, is very low. Eggs can only be found in faeces or urine when there is at least one pair of adult worms at the final location. The number of parasites increases as a function of the number of contacts with infected water. The exact latency between contamination and egg production is unknown. It is estimated that excretion of eggs starts after 40-50 days. The specific diagnosis of early schistosomiasis and Katayama fever relies essentially on serologic tests or preferably on PCR (if available). These assays are much more sensitive (up to four times) in the early phase of schistosomiasis than microscopic examination for typical eggs. Eosinophilia (sometimes exceeding 50%) is often present in patients with acute schistosomiasis (Katayama fever), but may be limited or absent in late fibrotic manifestations of the disease. BACKGROUND: Katayama fever is an acute clinical condition characterised by high fever, dry cough and general malaise occurring during early Schistosoma spp. infection. It is predomitly reported in travellers from non-endemic regions. Whereas the immunological response to Schistosoma infection is well characterised, alterations in inflammatory markers and coagulation in response to acute infection are poorly understood. METHODS: Here we report the clinical, laboratory and radiological characteristics of three returning travellers with Katayama fever. Inflammatory markers and coagulation status were assessed repeatedly during follow-up to characterise the host response to infection. Radiographic findings were correlated with clinical and laboratory markers. RESULTS: Clinical symptoms were suggestive of a significant inflammatory response in all patients including high fever (>39°C), cough, and general malaise. Classical inflammatory markers including blood sedimentation rate, C-reactive protein, and serum amyloid A were only moderately elevated. Marked eosinophilia (33-42% of white blood cells) was observed and persisted despite anti-inflammatory and anthelminthic treatment for up to 32 weeks. Analysis of blood coagulation markers indicated increased coagulability reflected by elevated D-dimer values (0.57-1.17 μg/ml) and high thrombin generating potentials (peak thrombin activity: 311-384 nM). One patient showed particularly high levels of microparticle-associated tissue factor activity at initial presentation (1.64 pg/ml). Multiple pulmonary and hepatic opacities demonstrated by computed tomography (CT) scanning were associated with raised inflammatory markers in one patient. CONCLUSIONS: The characterisation of the inflammatory response, blood coagulation parameters and radiological findings in three patients adds to our current understanding of Katayama fever and serves as a starting point for further systematic investigations of the pathophysiology of this acute helminthic infection.

List clinical trials for prevention of sarcopenia

Several clinical trials with androgen replacement therapy. Study was to evaluate the effect of omega-3 fatty acid supplementation on the rate of muscle protein synthesis. This trial was registered at clinical trials.gov as NCT00794079

The term "sarcopenia" describes the progressive decline of muscle mass, strength and function occurring with aging. It is not considered a disease, but the direct consequence of the aging process on the skeletal muscle. Multiple demographic (e.g. gender, race), biological (e.g. inflammatory status) and clinical (e.g. diabetes, metabolic syndrome, congestive heart failure, medications) factors are able to influence (positively or negatively) the skeletal muscle quality and quantity. The extreme paucity of clinical trials on sarcopenia in literature is mainly due to difficulties in designing studies able to isolate the aging process from its multiple and interconnected consequences. In the present review, we present the major factors to consider as potential sources of biased results when evaluating potential candidates for clinical trials on sarcopenia. The development of clinical trials exploring the nature of the sarcopenia process is urgent, but several controversial issues on this hallmark of aging still need clarification. BACKGROUND: Loss of muscle mass with aging is a major public health concern. Omega-3 (n-3) fatty acids stimulate protein anabolism in animals and might therefore be useful for the treatment of sarcopenia. However, the effect of omega-3 fatty acids on human protein metabolism is unknown. OBJECTIVE: The objective of this study was to evaluate the effect of omega-3 fatty acid supplementation on the rate of muscle protein synthesis in older adults. DESIGN: Sixteen healthy, older adults were randomly assigned to receive either omega-3 fatty acids or corn oil for 8 wk. The rate of muscle protein synthesis and the phosphorylation of key elements of the anabolic signaling pathway were evaluated before and after supplementation during basal, postabsorptive conditions and during a hyperaminoacidemic-hyperinsulinemic clamp. RESULTS: Corn oil supplementation had no effect on the muscle protein synthesis rate and the extent of anabolic signaling element phosphorylation in muscle. Omega-3 fatty acid supplementation had no effect on the basal rate of muscle protein synthesis (mean ± SEM: 0.051 ± 0.005%/h compared with 0.053 ± 0.008%/h before and after supplementation, respectively; P = 0.80) but augmented the hyperaminoacidemia-hyperinsulinemia-induced increase in the rate of muscle protein synthesis (from 0.009 ± 0.005%/h above basal values to 0.031 ± 0.003%/h above basal values; P < 0.01), which was accompanied by greater increases in muscle mTOR(Ser2448) (P = 0.08) and p70s6k(Thr389) (P < 0.01) phosphorylation. CONCLUSION: Omega-3 fatty acids stimulate muscle protein synthesis in older adults and may be useful for the prevention and treatment of sarcopenia. This trial was registered at clinical trials.gov as NCT00794079. Despite the existing limitations and controversies regarding the definition of sarcopenia and its clinical consequences, the current scientific evidence strongly suggests that muscle decline is a primary determit of the disabling process (and likely of other major health-related events). In fact, the muscle loss (in terms of mass as well as strength) occurring with aging has been growingly associated with mobility impairment and disability in older persons. Unfortunately, current evidence is mainly from observational studies. Times are mature to begin testing interventions aimed at modifying the sarcopenia process through the design and development of specific clinical trials. Considering the emergence of many promising interventions towards this age-related condition (e.g., physical exercise [in particular, resistance training], testosterone, antioxidant supplementations), the need for Phase II trial designs is high. In the present report, we discuss which are the major issues related to the design of Phase II clinical trials on sarcopenia with particular focus on the participant's characteristics to be considered as possible inclusion and exclusion criteria. Frailty syndrome is frequently encountered in elderly populations. Frailty has been defined as a geriatric syndrome of increased vulnerability to environmental factors. Although knowledge of this syndrome continues to develop, there are still many areas of uncertainty. The pathophysiological pathways, role of biomarkers in the early identification of this syndrome and best management strategies are still under investigation. This study is a literature review of articles published on frailty syndrome in English, French and Spanish. Frailty and aging are similar processes with some differences. Multiple pathophysiological models of frailty have been studied. Factors associated with frailty include hormonal adjustments, sarcopenia and vitamin deficiencies among others. Biomarkers have been studied, but they are not specific. Phenotypes have been developed, but early recognition and prevention of this syndrome are still difficult. In conclusion, early recognition of this syndrome is of paramount importance. Preventative strategies need to be studied. The role of specific biomarkers in early detection of frailty needs to be defined. Clinical trials are needed to find better interventions for this syndrome. Aging-associated decline in androgen levels is associated with risks of age-related disorders such as sarcopenia and disability in older adults. However, several clinical trials with androgen replacement therapy have failed to show clinical benefit. Recently, it has been reported that exercise could enhance intrinsic androgen levels, explaining one of the mechanisms of the beneficial effects induced by exercise.

Which is the database of molecular recognition features in membrane proteins?

mpMoRFsDB provides valuable information related to disorder-based protein-protein interactions in membrane proteins.

SUMMARY: Molecular recognition features (MoRFs) are small, intrinsically disordered regions in proteins that undergo a disorder-to-order transition on binding to their partners. MoRFs are involved in protein-protein interactions and may function as the initial step in molecular recognition. The aim of this work was to collect, organize and store all membrane proteins that contain MoRFs. Membrane proteins constitute ∼30% of fully sequenced proteomes and are responsible for a wide variety of cellular functions. MoRFs were classified according to their secondary structure, after interacting with their partners. We identified MoRFs in transmembrane and peripheral membrane proteins. The position of transmembrane protein MoRFs was determined in relation to a protein's topology. All information was stored in a publicly available mySQL database with a user-friendly web interface. A Jmol applet is integrated for visualization of the structures. mpMoRFsDB provides valuable information related to disorder-based protein-protein interactions in membrane proteins. AVAILABILITY: http://bioinformatics.biol.uoa.gr/mpMoRFsDB

Which database is available for the identification of chorion proteins in Lepidopteran proteomes?

LepChorionDB

Chorion proteins of Lepidoptera have a tripartite structure, which consists of a central domain and two, more variable, flanking arms. The central domain is highly conserved and it is used for the classification of chorion proteins into two major classes, A and B. Annotated and unreviewed Lepidopteran chorion protein sequences are available in various databases. A database, named LepChorionDB, was constructed by searching 5 different protein databases using class A and B central domain-specific profile Hidden Markov Models (pHMMs), developed in this work. A total of 413 Lepidopteran chorion proteins from 9 moths and 1 butterfly species were retrieved. These data were enriched and organised in order to populate LepChorionDB, the first relational database, available on the web, containing Lepidopteran chorion proteins grouped in A and B classes. LepChorionDB may provide insights in future functional and evolutionary studies of Lepidopteran chorion proteins and thus, it will be a useful tool for the Lepidopteran scientific community and Lepidopteran genome annotators, since it also provides access to the two pHMMs developed in this work, which may be used to discriminate A and B class chorion proteins. LepChorionDB is freely available at http://bioinformatics.biol.uoa.gr/LepChorionDB.

Are there any clinical trials of the effect of evening primrose oil on postmenopausal symptoms ?

Yes

OBJECTIVE: To evaluate the efficacy of gamolenic acid provided by evening primrose oil in treating hot flushes and sweating associated with the menopause. DESIGN: Randomised, double blind, placebo controlled study. SETTING: District general hospital and teaching hospital. SUBJECTS: 56 menopausal women suffering hot flushes at least three times a day. INTERVENTION: Four capsules twice a day of 500 mg evening primrose oil with 10 mg natural vitamin E or 500 mg liquid paraffin for six months. MAIN OUTCOME MEASURES: Change in the number of hot flushes or sweating episodes a month. RESULTS: 56 diaries were analysed, 28 from women taking gamolenic acid and 28 from those taking placebo. Only 18 women given gamolenic acid and 17 given placebo completed the trial. The mean (SE) improvement in the number of flushes in the last available treatment cycle compared with the control cycle was 1.9 (0.4) (P < 0.001) for daytime flushes and 0.7 (0.3) (P < 0.05) for night time flushes in women taking placebo; the corresponding values for women taking gamolenic acid were 0.5 (0.4) and 0.5 (0.3). In women taking gamolenic acid the only significant improvement was a reduction in the maximum number of night time flushes (1.4 (0.6); P < 0.05). CONCLUSION: Gamolenic acid offers no benefit over placebo in treating menopausal flushing. OBJECTIVE: To create an evidence-based position statement regarding the treatment of vasomotor symptoms associated with menopause. DESIGN: The North American Menopause Society (NAMS) enlisted clinicians and researchers acknowledged to be experts in the field of menopause-associated vasomotor symptoms to review the evidence obtained from the medical literature and develop a document for final approval by the NAMS Board of Trustees. RESULTS: For mild hot flashes, lifestyle-related strategies such as keeping the core body temperature cool, participating in regular exercise, and using paced respiration have shown some efficacy without adverse effects. Among nonprescription remedies, clinical trial results are insufficient to either support or refute efficacy for soy foods and isoflavone supplements (from either soy or red clover), black cohosh, or vitamin E; however, no serious side effects have been associated with short-term use of these therapies. Single clinical trials have found no benefit for dong quai, evening primrose oil, ginseng, a Chinese herbal mixture, acupuncture, or magnet therapy. Few data support the efficacy of topical progesterone cream; safety concerns should be the same as for other progestogen preparations. No clinical trials have been conducted on the use of licorice for hot flashes. Among nonhormonal prescription options, the antidepressants venlafaxine, paroxetine, and fluoxetine and the anticonvulsant gabapentin have demonstrated some efficacy for treating hot flashes and were well tolerated. Two antihypertensive agents, clonidine and methyldopa, have shown modest efficacy but with a relatively high rate of adverse effects. For moderate to severe hot flashes, systemic estrogen therapy, either alone (ET) or combined with progestogen (EPT) or in the form of estrogen-progestin oral contraceptives, has been shown to significantly reduce hot flash frequency and severity. Clinical trials have associated ET/EPT with adverse effects, including breast cancer, stroke, and thromboembolism. Several progestogens (both oral and intramuscular formulations) have shown efficacy in treating hot flashes, including women with a history of breast cancer, although no definitive data are available on long-term safety in these women. CONCLUSIONS: In women who need relief for mild vasomotor symptoms, NAMS recommends first considering lifestyle changes, either alone or combined with a nonprescription remedy, such as dietary isoflavones, black cohosh, or vitamin E. Prescription systemic estrogen-containing products remain the therapeutic standard for moderate to severe menopause-related hot flashes. Recommended options for women with concerns or contraindications relating to estrogen-containing treatments include prescription progestogens, venlafaxine, paroxetine, fluoxetine, or gabapentin. Clinicians are advised to enlist women's participation in decision making when weighing the benefits, harms, and scientific uncertainties of therapeutic options. Regardless of the management strategy adopted, treatment should be periodically reassessed as menopause-related vasomotor symptoms will abate over time without any intervention in most women. OBJECTIVE: To systematically review the literature regarding the efficacy and safety of nonestrogen treatments for menopause-associated vasomotor symptoms not due to cancer or chemotherapy. DATA SOURCES: Pertinent literature and clinical studies were identified by searching MEDLINE (1966-February 2004) and EMBASE (1959-February 2004) using the key search terms vasomotor symptoms, hot flashes, and menopause. Bibliographies of relevant articles were reviewed for additional references. STUDY SELECTION AND DATA EXTRACTION: English-language articles reporting efficacy and safety of nonestrogen treatment modalities for perimenopausal and postmenopausal vasomotor symptoms were evaluated. All articles identified from the data sources were evaluated, and all information deemed relevant was included. Emphasis was placed on randomized, double-blind, placebo-controlled clinical trials, as these provide the best efficacy and safety data. Studies evaluating treatment of vasomotor symptoms from other causes, such as cancer or chemotherapy, were excluded. DATA SYNTHESIS: Prescription medications reviewed for efficacy and safety in postmenopausal vasomotor symptoms include clonidine hydrochloride, danazol, gabapentin, methyldopa, mirtazapine, progestins, propranolol hydrochloride, selective serotonin-reuptake inhibitors (SSRIs), and venlafaxine. Nonprescription therapies reviewed include black cohosh, dong quai, evening primrose oil, physical activity, phytoestrogens, and red clover. CONCLUSIONS: According to this systematic literature review, postmenopausal vasomotor treatments that have been shown to be safe and effective in short-term use include black cohosh, exercise, gabapentin, medroxyprogesterone acetate, SSRIs (ie, paroxetine hydrochloride), and soy protein. Initial, small reports are suggestive for efficacy in menopausal vasomotor symptoms with megestrol acetate and venlafaxine. BACKGROUND: Interest in non-hormonal therapies for the treatment of menopausal symptoms has increased since the publication of adverse effects of estrogen replacement therapy. OBJECTIVE: To provide information on the efficacy of non-hormonal therapies for menopausal vasomotor symptoms based on evidence from published randomised controlled studies. METHODS: The Cochrane Database of Systematic Reviews (CDSR), MEDLINE, Alternative Therapies in Health and Medicine database (ATHMD) and Allied and Complementary Medicine database (AMED) were searched for randomised controlled trials in the English language reporting data on treatment of menopausal vasomotor symptoms. Trials including cancer breast patients were included. RESULTS: Our search identified 58 randomised controlled trials of which 11 involved the use of clonidine, six for SSRIs, four for gabapentin, seven for black cohosh, seven for red clover, 18 for phytoestrogens, two for ginseng, one for evening primrose, one for dong quai and one for vitamin E. Most trials had methodological deficiencies. CONCLUSION: There is evidence that clonidine, paroxetine, venlafaxine, gabapentin and black cohosh may be beneficial in the treatment of menopausal vasomotor symptoms in some women. Current evidence does not support the use of fluoxetine, red clover, phytoestrogens, Ginseng, evening primrose, dong quai and vitamin E. The side effects profile of these therapies should be considered. BACKGROUND: The most common complaints during climacteric are vasomotor symptoms. A circadian rhythm has been observed when hot flashes start; however, not much information is available in this field. AIMS: To analyze whether the time (morning/evening) of administration of a compound containing 60 mg of dry soy seed extract (glycine max) with 40% of total isoflavones, primrose oil and α-tocopherol modifies the effect on the climacteric syndrome. TRIAL DESIGN: Multicentric, observational, open, prospective, longitudinal and cross-sectional study. Subjects and methods. One thousand six hundred eighty-two postmenopausal women with climacteric symptoms were allocated in two groups in order to receive the treatment in the morning (Group 1) or in the evening (Group 2), switching administration time after 3 months. Clinical evaluation was carried out at 0, 3 and 6 months of follow-up using Blatt-Kupperman and Greene scales. RESULTS: 233 (13.9%) women dropped out from the study. Both administration times improved the climacteric symptoms after 3 and 6 months of treatment, showing a reduction in the scores of Blatt-Kupperman and Greene scales (p < 0.001). No differences between both groups during the follow-up were identified. CONCLUSIONS: The time of administration of isoflavones does not modify its effect on climacteric symptoms. PURPOSE: Hot flashes are common experience for menopausal women, and for many, are severe enough to significantly compromise their overall sense of well being and quality of life. The aim of this study was to compare the efficacy of evening primrose with placebo in improvement of menopausal hot flashes. METHODS: In a 6-week randomized clinical trial, a total of 56 menopausal women aged 45-59 years were participated in this study. The patients were asked for their hot flashes characteristics and responded to HFRDIS (hot flash related daily interference scale) questionnaire before and after the intervention. The participants were randomly assigned to take two capsules per day (totally 90 capsules for 6 weeks) of placebo or evening primrose (500 mg) for continuous 6 weeks. Then, the improvement in hot flashes was compared between two groups. RESULTS: The percent of improvement in hot flash frequency, severity and duration were 39, 42 and 19 %, in evening primrose group compared with 32, 32 and 18 % in placebo group, respectively. Although all three characters of hot flash was ameliorated in evening primrose arm, only its severity was significantly better in this arm compared with placebo group (P < 0.05). All HFRDIS score were significantly improved in two groups, but the percentage of improvement in social activities, relations with others, and sexuality was significantly superior to placebo group (P < 0.05). CONCLUSIONS: The application of oral evening primrose oil compared with placebo for controlling hot flashes may decrease more the intensity of attacks as well as ameliorating the HFRDIS score.

Is acid alpha-glucosidase the enzyme that causes Pompe disease when mutant?

Pompe disease is an autosomal recessive genetic disorder characterized by a deficiency of the enzyme responsible for degradation of lysosomal glycogen (acid α-glucosidase (GAA))

We describe an improved method for detecting deficiency of the acid hydrolase, alpha-1,4-glucosidase in leukocytes, the enzyme defect in glycogen storage disease Type II (Pompe disease). The procedure requires smaller volumes of blood and less time than previous methods. The assay involves the separation of leukocytes by Peter's method for beta-glucosidase and a modification of Salafsky and Nadler's fluorometric method for alpha-glucosidase. The nature of mutant acid alpha-glucosidase (AAG) in muscle was studied in 6 patients with Pompe disease, consisting of 2 each of the infantile, childhood and adult types. Anti-human liver AAG rabbit antibody prepared in the present study was confirmed to be monospecific by immunodiffusion, immunotitration and immunohistochemical methods. It was found by the immunodiffusion and enzyme immunoassay methods using this antibody that the mutation produced a normal amount of enzyme protein but the latter was an inactive form, suggesting structural gene mutation in 5 of the 6 cases. In the remaining childhood type case there was no detectable amount of enzyme protein, suggesting that the mutation causes a reduction in the amount of the enzyme protein or synthesis of unstable enzyme protein. Similarly, the enzyme activity of AAG was markedly reduced in all patients, but that of neutral alpha-glucosidase was the least reduced in the adult type, medium in the childhood type, and the most reduced in the infantile type. Infantile Pompe disease is a fatal genetic muscle disorder caused by a deficiency of acid alpha-glucosidase, a glycogen-degrading lysosomal enzyme. We constructed a plasmid containing a 5'-shortened human acid alpha-glucosidase cDNA driven by the cytomegalovirus promoter, as well as the aminoglycoside phosphotransferase and dihydrofolate reductase genes. Following transfection in dihydrofolate reductase-deficient Chinese hamster ovary cells, selection with Geneticin, and amplification with methotrexate, a cell line producing high levels of the alpha-glucosidase was established. In 48 hr, the cells cultured in Iscove's medium with 5 mM butyrate secreted 110-kDa precursor enzyme that accumulated to 91 micrograms.ml-1 in the medium (activity, > 22.6 mumol.hr-1.ml-1). This enzyme has a pH optimum similar to that of the mature form, but a lower Vmax and Km for 4-methylumbelliferyl-alpha-D-glucoside. It is efficiently taken up by fibroblasts from Pompe patients, restoring normal levels of acid alpha-glucosidase and glycogen. The uptake is blocked by mannose 6-phosphate. Following intravenous injection, high enzyme levels are seen in heart and liver. An efficient production system now exists for recombit human acid alpha-glucosidase targeted to heart and capable of correcting fibroblasts from patients with Pompe disease. Glycogen-storage disease type II, Pompe disease, is caused by the deficiency of acid alpha-D-glucosidase in lysosome. Previously we found that acid alpha-D-glucosidase did exist in the skin fibroblasts and there was also no difference of mRNA in quantity and size of Chinese infantile type Pompe disease patients in Taiwan. However, functional assay of the acid alpha-D-glucosidase of these patients showed its enzyme function to be defective. In the present study, first we identified a substitution site in four Chinese infantile patients with Pompe disease which is a cytidine to adenosine (C1935-->A) transversion at 5' end of exon 14 causing substitution of glutamic acid for aspartic acid at position 645 of the acid alpha-D-glucosidase. This substitution was introduced in wild-type cDNA and expressed in COS-1 cells. The Asp-645-->Glu substitution resulted in significant reduction of acid alpha-D-glucosidase activity. Second, according to the screening data in 25 Chinese Pompe disease patients using digestion of RT-PCR amplified specific fragment with Aat II, the restriction fragment length analysis showed that patients presented the 861 bp band and the normal individuals presented the 728 bp and 133 bp polymorphic bands. We found that the frequency of mutant allele is 0.8 in infantile patients with Chinese Pompe disease and 0 in normal individuals. These results therefore indicate that Asp-645-->Glu mutation results in infantile form of Pompe disease as the major cause in Chinese patients in Taiwan. Acid alpha-glucosidase (GAA) deficiency causes Pompe disease, a lethal lysosomal glycogen storage disease for which no effective treatment currently exists. We investigated the endocytic process in deficient cells of human recombit GAA produced in Chinese hamster ovary cells, and the potential of GAA-deficient Japanese acid maltase-deficient quail as a model for evaluating the enzyme replacement therapy for Pompe disease. After 24-h incubation with a single dose of recombit enzyme, intracellular GAA and glycogen levels in deficient human fibroblasts were normalized, and this correction lasted for 7 d. The 110-kD precursor recombit enzyme was processed to the 76-kD mature form within 24 h after uptake. Intracellular GAA levels in deficient quail fibroblasts and myoblasts were similarly corrected to their average normal levels within 24 h. Differences existed in the efficiency of endocytosis among subfractions of the enzyme, and among different cell types. Fractions with a larger proportion of precursor GAA were endocytosed more efficiently. Quail fibroblasts required a higher dose, 4200 nmol.h-1.mL-1 to normalize intracellular GAA levels than human fibroblasts, 1290 nmol.h-1.mL-1, whereas primary quail myoblasts required 2800 nmol.h-1.mL-1. In all three cell lines, the endocytosed enzyme localized to the lysosomes on immunofluorescence staining, and the endocytosis was inhibited by mannose 6-phosphate (Man-6-P) added to the culture medium. Despite structural differences in Man-6-P receptors between birds and mammals, these studies illustrate that Man-6-P receptor mediated endocytosis is present in quail muscle cells, and demonstrate the potential of acid maltase-deficient quail to test receptor mediated enzyme replacement therapy for Pompe disease. Pompe disease is caused by the congenital deficiency of the lysosomal enzyme acid alpha-glucosidase. The accumulation of lysosomal glycogen results in a fatal myopathy and cardiomyopathy. We developed an enzyme replacement therapy based on recombit human acid alpha-glucosidase enzyme targeted to the organs of interest by the presence of mannose-6-phosphate on this precursor enzyme and a manose-6-phosphate receptor present in muscle and heart. Using molecular techniques and following extensive selection, Chinese hamster ovary cells were developed that produced very large quantities of precursor human acid alpha-glucosidase in the culture medium. An improved method of purification of this precursor enzyme from tissue culture medium was developed. This purified precursor enzyme was taken up efficiently by patient's fibroblasts, and corrected with a single dose the lysosomal glycogen accumulation for one week. Finally, intravenous administration of the recombit enzyme corrected the pathology and symptoms of an animal model of this disorder, the acid alpha-glucosidase deficient Japanese quail. BACKGROUND: Pompe disease is an autosomal recessive disorder of glycogen metabolism that is characterized by a deficiency of the lysosomal acid alpha-glucosidase. Enzyme replacement therapy for the infantile and juvenile forms of Pompe disease currently is undergoing clinical trials. Early diagnosis before the onset of irreversible pathology is thought to be critical for maximum efficacy of current and proposed therapies. In the absence of a family history, the presymptomatic detection of these disorders ideally can be achieved through a newborn-screening program. Currently, the clinical diagnosis of Pompe disease is confirmed by the virtual absence, in infantile onset, or a marked reduction, in juvenile and adult onset, of acid alpha-glucosidase activity in muscle biopsies and cultured fibroblasts. These assays are invasive and not suited to large-scale screening. METHODS: A sensitive immune-capture enzyme activity assay for the measurement of acid alpha-glucosidase protein was developed and used to determine the activity of this enzyme in dried-blood spots from newborn and adult controls, Pompe-affected individuals, and obligate heterozygotes. RESULTS: Pompe-affected individuals showed an almost total absence of acid alpha-glucosidase activity in blood spots. The assay showed a sensitivity and specificity of 100% for the identification of Pompe-affected individuals. CONCLUSIONS: The determination of acid alpha-glucosidase activity in dried-blood spots is a useful, noninvasive diagnostic assay for the identification of Pompe disease. With further validation, this procedure could be adapted for use with blood spots collected in newborn-screening programs. Although many lysosomal disorders are corrected by a small amount of the missing enzyme, it has been generally accepted that 20-30% of normal acid alpha-glucosidase (GAA) activity, provided by gene or enzyme replacement therapy, would be required to reverse the myopathy and cardiomyopathy in Pompe disease. We have addressed the issue of reversibility of the disease in the Gaa(-/-) mouse model. We have made transgenic lines expressing human GAA in skeletal and cardiac muscle of Gaa(-/-) mice, and we turned the transgene on at different stages of disease progression by using a tetracycline-controllable system. We have demonstrated that levels of 20-30% of normal activity are indeed sufficient to clear glycogen in the heart of young Gaa(-/-) mice, but not in older mice with a considerably higher glycogen load. However, in skeletal muscle-a major organ affected in infantile and in milder, late-onset variants in humans-induction of GAA expression in young Gaa(-/-) mice to levels greatly exceeding wildtype values did not result in full phenotypic correction, and some muscle fibers showed little or no glycogen clearance. The results demonstrate that complete reversal of pathology in skeletal muscle or long-affected heart muscle will require much more enzyme than previously expected or a different approach. Pompe disease is an autosomal recessive muscle-wasting disorder caused by the deficiency of the lysosomal enzyme acid alpha-glucosidase. Due to virtual absence of acid alpha-glucosidase, patients with classical infantile Pompe disease develop progressive cardiomyopathy, skeletal muscle weakness and respiratory insufficiency leading to death in early infancy. We report on the results of a phase II clinical trial including two patients with classical infantile Pompe disease receiving enzyme replacement therapy over a period of 48 weeks by weekly infusions. Recombit acid alpha-glucosidase was derived from the milk of transgenic rabbits. Safety was evaluated by recording adverse events while clinical efficacy was evaluated by ventilator-free survival, left ventricular mass index, motor development as well as histologic and biochemical analysis of muscle biopsies. This therapy was in general well-tolerated. There was an overall improvement in left ventricular mass, cardiac function, skeletal muscle function and histological appearance of skeletal muscle. PURPOSE: Infantile Pompe disease is caused by deficiency of lysosomal acid alpha-glucosidase. Trials with recombit human acid alpha-glucosidase enzyme replacement therapy (ERT) show a decrease in left ventricular mass and improved function. We evaluated 24-hour ambulatory electrocardiograms (ECGs) at baseline and during ERT in patients with infantile Pompe disease. METHODS: Thirty-two ambulatory ECGs were evaluated for 12 patients with infantile Pompe disease from 2003 to 2005. Patients had a median age of 7.4 months (2.9-37.8 months) at initiation of ERT. Ambulatory ECGs were obtained at determined intervals and analyzed. RESULTS: Significant ectopy was present in 2 of 12 patients. Patient 1 had 211 and 229 premature ventricular contractions (0.2% of heart beats) at baseline and at 11.5 weeks of ERT, respectively. Patient 2 had 10,445 premature ventricular contractions (6.7% of heart beats) at 11 weeks of therapy. CONCLUSION: Infantile Pompe disease may have preexisting ectopy; it may also develop during the course of ERT. Therefore, routinely monitoring patients using 24-hour ambulatory ECGs is useful. Periods of highest risk may be early in the course of ERT when there is a substantial decrease in left ventricular mass and an initial decrease in ejection fraction. Glycogen storage disease type II (GSDII; Pompe disease or acid maltase deficiency) is an autosomal recessive disorder caused by lysosomal acid alpha-glucosidase (AalphaGlu) deficiency and manifests predomitly as skeletal muscle weakness. Defects in post-translational modification and transport of mutant AalphaGlu species are frequently encountered and may potentially be corrected with chaperone-mediated therapy. In the present study, we have tested this hypothesis by using deoxynojirimycin and derivatives as chemical chaperones to correct the AalphaGlu deficiency in cultured fibroblasts from patients with GSDII. Four mutant phenotypes were chosen: Y455F/Y455F, P545L/P545L, 525del/R600C and D645E/R854X. In case of Y455F/Y455F and P545L/P545L, N-(n-butyl)deoxynojirimycin (NB-DNJ) restored the transport, maturation and activity of AalphaGlu in a dose dependent manner, while it had no effect on the reference enzyme beta-hexosaminidase. NB-DNJ promoted export from the endoplasmic reticulum (ER) to the lysosomes and stabilized the activity of mutant AalphaGlu species, Y455F and P545L, inside the lysosomes. In long-term culture, the AalphaGlu activity in the fibroblasts from the patients with mutant phenotypes, Y455F/Y455F and P545L/P545L, increased up to 14.0- and 7.9-fold, respectively, in the presence of 10mumol/L NB-DNJ. However, the effect of NB-DNJ on Y455F/Y455F subsided quickly after removal of the compound. We conclude that NB-DNJ acts in low concentration as chemical chaperone for certain mutant forms of AalphaGlu that are trapped in the ER, poorly transported or labile in the lysosomal environment. Chemical chaperone therapy could create new perspectives for therapeutic intervention in GSDII. Pompe disease (glycogen storage disease II) is caused by mutations in the acid alpha-glucosidase gene. The most common form is rapidly progressive with glycogen storage, particularly in muscle, which leads to profound weakness, cardiac failure, and death by the age of 2 years. Although usually considered a muscle disease, glycogen storage also occurs in the CNS. We evaluated the progression of neuropathologic and behavioral abnormalities in a Pompe disease mouse model (6neo/6neo) that displays many features of the human disease. Homozygous mutant mice store excess glycogen within large neurons of hindbrain, spinal cord, and sensory ganglia by the age of 1 month; accumulations then spread progressively within many CNS cell types. "Silver degeneration" and Fluoro-Jade C stains revealed severe degeneration in axon terminals of primary sensory neurons at 3 to 9 months. These abnormalities were accompanied by progressive behavioral impairment on rotorod, wire hanging, and foot fault tests. The extensive neuropathologic alterations in this model suggest that therapy of skeletal and cardiac muscle disorders by systemic enzyme replacement therapy may not be sufficient to reverse functional deficits due to CNS glycogen storage, particularly early-onset, rapidly progressive disease. A better understanding of the basis for clinical manifestations is needed to correlate CNS pathology with Pompe disease manifestations. To elucidate the mechanism underlying transport and processing defects from the viewpoint of enzyme folding, we constructed three-dimensional models of human acid alpha-glucosidase encompassing 27 relevant amino acid substitutions by means of homology modeling. Then, we determined in each separate case the number of affected atoms, the root-mean-square distance value and the solvent-accessible surface area value. The analysis revealed that the amino acid substitutions causing a processing or transport defect responsible for Pompe disease were widely spread over all of the five domains comprising the acid alpha-glucosidase. They were distributed from the core to the surface of the enzyme molecule, and the predicted structural changes varied from large to very small. Among the structural changes, we paid particular attention to G377R and G483R. These two substitutions are predicted to cause electrostatic changes in neighboring small regions on the molecular surface. The quality control system of the endoplasmic reticulum apparently detects these very small structural changes and degrades the mutant enzyme precursor (G377R), but also the cellular sorting system might be misled by these minor changes whereby the precursor is secreted instead of being transported to lysosomes (G483R). Pompe disease is a lysosomal storage disorder (LSD) caused by mutations in the gene that encodes acid alpha-glucosidase (GAA). Recently, small molecule pharmacological chaperones have been shown to increase protein stability and cellular levels for mutant lysosomal enzymes and have emerged as a new therapeutic strategy for the treatment of LSDs. In this study, we characterized the pharmacological chaperone 1-deoxynojirimycin (DNJ) on 76 different mutant forms of GAA identified in Pompe disease. DNJ significantly increased enzyme activity and protein levels for 16 different GAA mutants in patient-derived fibroblasts and in transiently transfected COS-7 cells. Additionally, DNJ increased the processing of these GAA mutants to their mature lysosomal forms, suggesting facilitated trafficking through the secretory pathway. Immunofluorescence microscopy studies showed increased colocalization of GAA with the lysosomal marker LAMP2 after incubation with DNJ, confirming increased lysosomal trafficking. Lastly, a GAA structural model was constructed based on the related eukaryotic glucosidase maltase-glucoamylase. The mutated residues identified in responsive forms of GAA are located throughout most of the structural domains, with half of these residues located in two short regions within the catalytic domain. Taken together, these data support further evaluation of DNJ as a potential treatment for Pompe disease in patients that express responsive forms of GAA. Pompe disease is a lysosomal storage disease (LSD) caused by a deficiency in the lysosomal enzyme acid alpha-glucosidase. In several LSDs, enzyme inhibitors have been used as small molecule chaperones to facilitate and increase the translocation of mutant protein from the endoplasmic reticulum to the lysosome. Enzyme activators with chaperone activity would be even more desirable as they would not inhibit the enzyme after translocation and might potentiate the activity of the enzyme that is successfully translocated. Herein we report our initial findings of a new series of acid alpha-glucosidase activators. Pompe disease is an inherited lysosomal storage disorder that results from a deficiency in acid α-glucosidase (GAA) activity due to mutations in the GAA gene. Pompe disease is characterized by accumulation of lysosomal glycogen primarily in heart and skeletal muscles, which leads to progressive muscle weakness. We have shown previously that the small molecule pharmacological chaperone AT2220 (1-deoxynojirimycin hydrochloride, duvoglustat hydrochloride) binds and stabilizes wild-type as well as multiple mutant forms of GAA, and can lead to higher cellular levels of GAA. In this study, we examined the effect of AT2220 on mutant GAA, in vitro and in vivo, with a primary focus on the endoplasmic reticulum (ER)-retained P545L mutant form of human GAA (P545L GAA). AT2220 increased the specific activity of P545L GAA toward both natural (glycogen) and artificial substrates in vitro. Incubation with AT2220 also increased the ER export, lysosomal delivery, proteolytic processing, and stability of P545L GAA. In a new transgenic mouse model of Pompe disease that expresses human P545L on a Gaa knockout background (Tg/KO) and is characterized by reduced GAA activity and elevated glycogen levels in disease-relevant tissues, daily oral administration of AT2220 for 4 weeks resulted in significant and dose-dependent increases in mature lysosomal GAA isoforms and GAA activity in heart and skeletal muscles. Importantly, oral administration of AT2220 also resulted in significant glycogen reduction in disease-relevant tissues. Compared to daily administration, less-frequent AT2220 administration, including repeated cycles of 4 or 5 days with AT2220 followed by 3 or 2 days without drug, respectively, resulted in even greater glycogen reductions. Collectively, these data indicate that AT2220 increases the specific activity, trafficking, and lysosomal stability of P545L GAA, leads to increased levels of mature GAA in lysosomes, and promotes glycogen reduction in situ. As such, AT2220 may warrant further evaluation as a treatment for Pompe disease. Pompe disease is a systemic metabolic disorder characterized by lack of acid-alpha glucosidase (GAA) resulting in ubiquitous lysosomal glycogen accumulation. Respiratory and ambulatory dysfunction are prominent features in patients with Pompe yet the mechanism defining the development of muscle weakness is currently unclear. Transgenic animal models of Pompe disease mirroring the patient phenotype have been invaluable in mechanistic and therapeutic study. Here, we demonstrate significant pathological alterations at neuromuscular junctions (NMJs) of the diaphragm and tibialis anterior muscle as prominent features of disease pathology in Gaa knockout mice. Postsynaptic defects including increased motor endplate area and fragmentation were readily observed in Gaa(-/-) but not wild-type mice. Presynaptic neuropathic changes were also evident, as demonstrated by significant reduction in the levels of neurofilament proteins, and alterations in axonal fiber diameter and myelin thickness within the sciatic and phrenic nerves. Our data suggest the loss of NMJ integrity is a primary contributor to the decline in respiratory and ambulatory function in Pompe and arises from both pre- and postsynaptic pathology. These observations highlight the importance of systemic phenotype correction, specifically restoration of GAA to skeletal muscle and the nervous system for treatment of Pompe disease. Pompe disease is an autosomal recessive myopathic disorder caused by the deficiency of lysosomal acid α-glucosidase (GAA). Recently, we showed that function of mutant GAA in fibroblasts derived from Pompe disease patient carrying c.546G>T mutation is improved by treatment with proteasome inhibitor bortezomib as well as pharmacological chaperone (PC). However, bortezomib-responsive GAA mutations are not fully characterized. In this study, we showed the effect of bortezomib on different mutants of GAA in patient fibroblasts and transiently expressed HEK293T cells. Bortezomib increased the maturation and residual activity of GAA in patient fibroblasts carrying PC-responsive M519V and PC-unresponsive C647W mutations. Enhanced colocalization of GAA with lysosomal marker LAMP2 was also observed in patient fibroblasts after treatment with bortezomib. When four distinct mutant GAAs, which show different response to PC, were overexpressed in HEK293T cells, bortezomib improved the activity of M519V, S529V, and C647W in them (1.3-5.9-fold). These results indicate that bortezomib enhances the activity of some PC-unresponsive GAA mutants as well as PC-responsive mutants. Pompe disease is an autosomal recessive genetic disorder characterized by a deficiency of the enzyme responsible for degradation of lysosomal glycogen (acid α-glucosidase (GAA)). Cardiac dysfunction and respiratory muscle weakness are primary features of this disorder. To attenuate the progressive and rapid accumulation of glycogen resulting in cardiorespiratory dysfunction, adult Gaa (-/-) mice were administered a single systemic injection of rAAV2/9-DES-hGAA (AAV9-DES) or bimonthly injections of recombit human GAA (enzyme replacement therapy (ERT)). Assessment of cardiac function and morphology was measured 1 and 3 months after initiation of treatment while whole-body plethysmography and diaphragmatic contractile function was evaluated at 3 months post-treatment in all groups. Gaa (-/-) animals receiving either AAV9-DES or ERT demonstrated a significant improvement in cardiac function and diaphragmatic contractile function as compared to control animals. AAV9-DES treatment resulted in a significant reduction in cardiac dimension (end diastolic left ventricular mass/gram wet weight; EDMc) at 3 months postinjection. Neither AAV nor ERT therapy altered minute ventilation during quiet breathing (eupnea). However, breathing frequency and expiratory time were significantly improved in AAV9-DES animals. These results indicate systemic delivery of either strategy improves cardiac function but AAV9-DES alone improves respiratory parameters at 3 months post-treatment in a murine model of Pompe disease.

Which kinase is inhibited by Tripolin A?

Tripolin A reduced the localization of pAurora A on spindle microtubules (MTs), affected centrosome integrity, spindle formation and length, as well as MT dynamics in interphase, consistent with Aurora A inhibition by RNAi or other specific inhibitors, such as MLN8054 or MLN8237. Interestingly, Tripolin A affected the gradient distribution towards the chromosomes, but not the MT binding of HURP (Hepatoma Up-Regulated Protein), a MT-associated protein (MAP) and substrate of the Aurora A kinase. Therefore Tripolin A reveals a new way of regulating mitotic MT stabilizers through Aurora A phosphorylation. Mitotic regulators exhibiting gain of function in tumor cells are considered useful cancer therapeutic targets for the development of small-molecule inhibitors.

Mitotic regulators exhibiting gain of function in tumor cells are considered useful cancer therapeutic targets for the development of small-molecule inhibitors. The human Aurora kinases are a family of such targets. In this study, from a panel of 105 potential small-molecule inhibitors, two compounds Tripolin A and Tripolin B, inhibited Aurora A kinase activity in vitro. In human cells however, only Tripolin A acted as an Aurora A inhibitor. We combined in vitro, in vivo single cell and in silico studies to demonstrate the biological action of Tripolin A, a non-ATP competitive inhibitor. Tripolin A reduced the localization of pAurora A on spindle microtubules (MTs), affected centrosome integrity, spindle formation and length, as well as MT dynamics in interphase, consistent with Aurora A inhibition by RNAi or other specific inhibitors, such as MLN8054 or MLN8237. Interestingly, Tripolin A affected the gradient distribution towards the chromosomes, but not the MT binding of HURP (Hepatoma Up-Regulated Protein), a MT-associated protein (MAP) and substrate of the Aurora A kinase. Therefore Tripolin A reveals a new way of regulating mitotic MT stabilizers through Aurora A phosphorylation. Tripolin A is predicted to bind Aurora A similarly but not identical to MLN8054, therefore it could be used to dissect pathways orchestrated by Aurora kinases as well as a scaffold for further inhibitor development.

Is the optogenetics tool ChR2 light-sensitive?

Channelrhodospin-2 (ChR2) is a light-sensitive ion channel that has emerged as new optogenetics tool.

Optogenetic technology, also known as optogenetics, is a novel multidisciplinary field in biotechnology that integrates genetic engineering, electrophysiology, and optical and electronic engineering. This recently developed technology has evolved rapidly and generated considerable excitement in neuroscience research. This technology successfully solves the severe problem of achieving both high temporal and spatial precision within intact neural tissues of animals that electrical stimulation and pharmacological methods cannot achieve. It allows neurons to express light-sensitive genes that enable the identification, dissection, and manipulation of specific neural populations and their connections in the tissues and organs of awake animals with unprecedented spatial and temporal precision. Light-sensitive genes chiefly including the genetically targeted light-gated channels channelrhodopsin-2 (ChR2) and halorhodopsin (NpHR) cause intracellular ion flow during optical illumination. Subsequently, the neurons undergo a series of changes resulting from membrane depolarization or hyperpolarization. To date, there are many published research articles and reviews that describe this new technology; however, few of the reports concern its application to neuropsychiatric diseases. In this review, we summarize the most recent optogenetic research in these diseases, including Parkinson's disease (PD), epilepsy, schizophrenia, anxiety, fear, reward behaviors, and sleep disorders. We propose that novel optogenetics technology creates excellent opportunities for innovative treatment strategies of neuropsychiatric diseases. For therapies based on human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (CM) to be effective, arrhythmias must be avoided. Towards achieving this goal, light-activated channelrhodopsin-2 (ChR2), a cation channel activated with 480 nm light, and a first generation halorhodopsin (NpHR1.0), an anion pump activated by 580 nm light, have been introduced into hiPSC. By using in vitro approaches, hiPSC-CM are able to be optogenetically activated and inhibited. ChR2 and NpHR1.0 are stably transduced into undifferentiated hiPSC via a lentiviral vector. Via directed differentiation, both wildtype hiPSC-CM (hiPSC(WT)-CM) and hiPSC(ChR2/NpHR)-CM are produced and subjected to both electrical and optical stimulation. Both hiPSC(WT)-CM and hiPSC(ChR2/NpHR)-CM respond to traditional electrical stimulation and produce similar contractility features but only hiPSC(ChR2/NpHR)-CM can be synchronized and inhibited by optical stimulation. Here it is shown that light sensitive proteins can enable in vitro optical control of hiPSC-CM. For future therapy, in vivo optical stimulation could allow precise and specific synchronization of implanted hiPSC-CM with patient cardiac rates and rhythms. A growing number of genetically encoded tools are becoming available that allow non-invasive manipulation of the neural activity of specific neurons in Drosophila melanogaster. Chief among these are optogenetic tools, which enable the activation or silencing of specific neurons in the intact and freely moving animal using bright light. Channelrhodopsin (ChR2) is a light-activated cation channel that, when activated by blue light, causes depolarization of neurons that express it. ChR2 has been effective for identifying neurons critical for specific behaviors, such as CO(2) avoidance, proboscis extension and giant-fiber mediated startle response. However, as the intense light sources used to stimulate ChR2 also stimulate photoreceptors, these optogenetic techniques have not previously been used in the visual system. Here, we combine an optogenetic approach with a mutation that impairs phototransduction to demonstrate that activation of a cluster of loom-sensitive neurons in the fly's optic lobe, Foma-1 neurons, can drive an escape behavior used to avoid collision. We used a null allele of a critical component of the phototransduction cascade, phospholipase C-β, encoded by the norpA gene, to render the flies blind and also use the Gal4-UAS transcriptional activator system to drive expression of ChR2 in the Foma-1 neurons. Individual flies are placed on a small platform surrounded by blue LEDs. When the LEDs are illuminated, the flies quickly take-off into flight, in a manner similar to visually driven loom-escape behavior. We believe that this technique can be easily adapted to examine other behaviors in freely moving flies. The advent of optogenetics provides a new direction for the field of neuroscience and biotechnology, serving both as a refined investigative tool and as potential cure for many medical conditions via genetic manipulation. Although still in its infancy, recent advances in optogenetics has made it possible to remotely manipulate in vivo cellular functions using light. Coined Nature Methods' 'Method of the Year' in 2010, the optogenetic toolbox has the potential to control cell, tissue and even animal behaviour. This optogenetic toolbox consists of light-sensitive proteins that are able to modulate membrane potential in response to light. Channelrhodopsins (ChR) are light-gated microbial ion channels, which were first described in green algae. ChR2 (a subset of ChR) is a seven transmembrane α helix protein, which evokes membrane depolarization and mediates an action potential upon photostimulation with blue (470 nm) light. By contrast to other seven-transmembrane proteins that require second messengers to open ion channels, ChR2 form ion channels themselves, allowing ultrafast depolarization (within 50 milliseconds of illumination). It has been shown that integration of ChR2 into various tissues of mice can activate neural circuits, control heart muscle contractions, and even restore breathing after spinal cord injury. More compellingly, a plethora of evidence has indicated that artificial expression of ChR2 in retinal ganglion cells can reinstate visual perception in mice with retinal degeneration. Optogenetic methods have emerged as a powerful tool for elucidating neural circuit activity underlying a diverse set of behaviors across a broad range of species. Optogenetic tools of microbial origin consist of light-sensitive membrane proteins that are able to activate (e.g., channelrhodopsin-2, ChR2) or silence (e.g., halorhodopsin, NpHR) neural activity ingenetically-defined cell types over behaviorally-relevant timescales. We first demonstrate a simple approach for adeno-associated virus-mediated delivery of ChR2 and NpHR transgenes to the dorsal subiculum and prelimbic region of the prefrontal cortex in rat. Because ChR2 and NpHR are genetically targetable, we describe the use of this technology to control the electrical activity of specific populations of neurons (i.e., pyramidal neurons) embedded in heterogeneous tissue with high temporal precision. We describe herein the hardware, custom software user interface, and procedures that allow for simultaneous light delivery and electrical recording from transduced pyramidal neurons in an anesthetized in vivo preparation. These light-responsive tools provide the opportunity for identifying the causal contributions of different cell types to information processing and behavior. Channelrhodopsins-2 (ChR2) are a class of light sensitive proteins that offer the ability to use light stimulation to regulate neural activity with millisecond precision. In order to address the limitations in the efficacy of the wild-type ChR2 (ChRwt) to achieve this objective, new variants of ChR2 that exhibit fast mon-exponential photocurrent decay characteristics have been recently developed and validated. In this paper, we investigate whether the framework of transition rate model with 4 states, primarily developed to mimic the biexponential photocurrent decay kinetics of ChRwt, as opposed to the low complexity 3 state model, is warranted to mimic the mono-exponential photocurrent decay kinetics of the newly developed fast ChR2 variants: ChETA (Gunaydin et al., Nature Neurosci. 13:387-392, 2010) and ChRET/TC (Berndt et al., Proc. Natl. Acad. Sci. 108:7595-7600, 2011). We begin by estimating the parameters of the 3-state and 4-state models from experimental data on the photocurrent kinetics of ChRwt, ChETA, and ChRET/TC. We then incorporate these models into a fast-spiking interneuron model (Wang and Buzsaki, J. Neurosci. 16:6402-6413, 1996) and a hippocampal pyramidal cell model (Golomb et al., J. Neurophysiol. 96:1912-1926, 2006) and investigate the extent to which the experimentally observed neural response to various optostimulation protocols can be captured by these models. We demonstrate that for all ChR2 variants investigated, the 4 state model implementation is better able to capture neural response consistent with experiments across wide range of optostimulation protocol. We conclude by analytically investigating the conditions under which the characteristic specific to the 3-state model, namely the monoexponential photocurrent decay of the newly developed variants of ChR2, can occur in the framework of the 4-state model. Channelrhodospin-2 (ChR2), a light-sensitive ion channel, and its variants have emerged as new excitatory optogenetic tools not only in neuroscience, but also in other areas, including cardiac electrophysiology. An accurate quantitative model of ChR2 is necessary for in silico prediction of the response to optical stimulation in realistic tissue/organ settings. Such a model can guide the rational design of new ion channel functionality tailored to different cell types/tissues. Focusing on one of the most widely used ChR2 mutants (H134R) with enhanced current, we collected a comprehensive experimental data set of the response of this ion channel to different irradiances and voltages, and used these data to develop a model of ChR2 with empirically-derived voltage- and irradiance- dependence, where parameters were fine-tuned via simulated annealing optimization. This ChR2 model offers: 1) accurate inward rectification in the current-voltage response across irradiances; 2) empirically-derived voltage- and light-dependent kinetics (activation, deactivation and recovery from inactivation); and 3) accurate amplitude and morphology of the response across voltage and irradiance settings. Temperature-scaling factors (Q10) were derived and model kinetics was adjusted to physiological temperatures. Using optical action potential clamp, we experimentally validated model-predicted ChR2 behavior in guinea pig ventricular myocytes. The model was then incorporated in a variety of cardiac myocytes, including human ventricular, atrial and Purkinje cell models. We demonstrate the ability of ChR2 to trigger action potentials in human cardiomyocytes at relatively low light levels, as well as the differential response of these cells to light, with the Purkinje cells being most easily excitable and ventricular cells requiring the highest irradiance at all pulse durations. This new experimentally-validated ChR2 model will facilitate virtual experimentation in neural and cardiac optogenetics at the cell and organ level and provide guidance for the development of in vivo tools. AIMS: Optogenetics approaches, utilizing light-sensitive proteins, have emerged as unique experimental paradigms to modulate neuronal excitability. We aimed to evaluate whether a similar strategy could be used to control cardiac-tissue excitability. METHODS AND RESULTS: A combined cell and gene therapy strategy was developed in which fibroblasts were transfected to express the light-activated depolarizing channel Channelrhodopsin-2 (ChR2). Patch-clamp studies confirmed the development of a robust inward current in the engineered fibroblasts following monochromatic blue-light exposure. The engineered cells were co-cultured with neonatal rat cardiomyocytes (or human embryonic stem cell-derived cardiomyocytes) and studied using a multielectrode array mapping technique. These studies revealed the ability of the ChR2-fibroblasts to electrically couple and pace the cardiomyocyte cultures at varying frequencies in response to blue-light flashes. Activation mapping pinpointed the source of this electrical activity to the engineered cells. Similarly, diffuse seeding of the ChR2-fibroblasts allowed multisite optogenetics pacing of the co-cultures, significantly shortening their electrical activation time and synchronizing contraction. Next, optogenetics pacing in an in vitro model of conduction block allowed the resynchronization of the tissue's electrical activity. Finally, the ChR2-fibroblasts were transfected to also express the light-sensitive hyperpolarizing proton pump Archaerhodopsin-T (Arch-T). Seeding of the ChR2/ArchT-fibroblasts allowed to either optogentically pace the cultures (in response to blue-light flashes) or completely suppress the cultures' electrical activity (following continuous illumination with 624 nm monochromatic light, activating ArchT). CONCLUSIONS: The results of this proof-of-concept study highlight the unique potential of optogenetics for future biological pacemaking and resynchronization therapy applications and for the development of novel anti-arrhythmic strategies. Precise spatial and temporal manipulation of neural activity in specific genetically defined cell populations is now possible with the advent of optogenetics. The emerging field of optogenetics consists of a set of naturally-occurring and engineered light-sensitive membrane proteins that are able to activate (e.g. channelrhodopsin-2, ChR2) or silence (e.g. halorhodopsin, NpHR) neural activity. Here we demonstrate the technique and the feasibility of using novel adeno-associated viral (AAV) tools to activate (AAV-CaMKllα-ChR2-eYFP) or silence (AAV-CaMKllα-eNpHR3.0-eYFP) neural activity of rat prefrontal cortical prelimbic (PL) pyramidal neurons  in vivo.  In vivo single unit extracellular recording of ChR2-transduced pyramidal neurons showed that delivery of brief (10 ms) blue (473 nm) light-pulse trains up to 20 Hz via a custom fiber optic-coupled recording electrode (optrode) induced spiking with high fidelity at 20 Hz for the duration of recording (up to two hours in some cases). To silence spontaneously active neurons, we transduced them with the NpHR construct and administered continuous green (532 nm) light to completely inhibit action potential activity for up to 10 seconds with 100% fidelity in most cases. These versatile photosensitive tools, combined with optrode recording methods, provide experimental control over activity of genetically defined neurons and can be used to investigate the functional relationship between neural activity and complex cognitive behavior. The most widely used optogenetic tool, Channelrhodopsin2 (ChR2), is both light- and voltage-sensitive. A light-triggered action potential or light-driven perturbations of ongoing electrical activity provide instant voltage feedback, shaping ChR2 current. Therefore, depending on the cell type and the light pulse duration, the typically reported voltage-clamp-measured ChR2 current traces are often not a good surrogate for the ChR2 current during optically-triggered action potentials. We discuss two experimental methods to reveal ChR2 current during an action potential: an "optical AP clamp" and its approximation employing measured current-voltage curve for ChR2. The methods are applicable to voltage- and light-sensitive ion currents operating in excitable cells, e.g. cardiomyocytes or neurons. Optogenetics is a novel technology that combines optics and genetics by optical control of microbial opsins, targeted to living cell membranes. The versatility and the electrophysiologic characteristics of the light-sensitive ion-channels channelrhodopsin-2 (ChR2), halorhodopsin (NpHR), and the light-sensitive proton pump archaerhodopsin-3 (Arch) make these optogenetic tools potent candidates in controlling neuronal firing in models of epilepsy and in providing insights into the physiology and pathology of neuronal network organization and synchronization. Opsins allow selective activation of excitatory neurons and inhibitory interneurons, or subclasses of interneurons, to study their activity patterns in distinct brain-states in vivo and to dissect their role in generation of synchrony and seizures. The influence of gliotransmission on epileptic network function is another topic of great interest that can be further explored by using light-activated Gq protein-coupled opsins for selective activation of astrocytes. The ever-growing optogenetic toolbox can also be combined with emerging techniques that have greatly expanded our ability to record specific subtypes of cortical and hippocampal neurons in awake behaving animals such as juxtacellular recording and two-photon guided whole-cell recording, to identify the specific subtypes of neurons that are altered in epileptic networks. Finally, optogenetic tools allow rapid and reversible suppression of epileptic electroencephalography (EEG) activity upon photoactivation. This review outlines the most recent advances achieved with optogenetic techniques in the field of epilepsy by summarizing the presentations contributed to the 13th ILAE WONOEP meeting held in the Laurentian Mountains, Quebec, in June 2013. Insulin is secreted from the pancreatic β-cells in response to elevated glucose. In intact islets the capacity for insulin release is determined by a complex interplay between different cell types. This has made it difficult to specifically assess the role of β-cell defects to the insulin secretory impairment in type 2 diabetes. Here we describe a new approach, based on optogenetics, that enables specific investigation of β-cells in intact islets. We used transgenic mice expressing the light-sensitive cation channel Channelrhodopsin-2 (ChR2) under control of the insulin promoter. Glucose tolerance in vivo was assessed using intraperitoneal glucose tolerance tests, and glucose-induced insulin release was measured from static batch incubations. ChR2 localization was determined by fluorescence confocal microscopy. The effect of ChR2 stimulation with blue LED light was assessed using Ca(2+) imaging and static islet incubations. Light stimulation of islets from transgenic ChR2 mice triggered prompt increases in intracellular Ca(2+). Moreover, light stimulation enhanced insulin secretion in batch-incubated islets at low and intermediate but not at high glucose concentrations. Glucagon release was not affected. Beta-cells from mice rendered diabetic on a high-fat diet exhibited a 3.5-fold increase in light-induced Ca(2+) influx compared with mice on a control diet. Furthermore, light enhanced insulin release also at high glucose in these mice, suggesting that high-fat feeding leads to a compensatory potentiation of the Ca(2+) response in β-cells. The results demonstrate the usefulness and versatility of optogenetics for studying mechanisms of perturbed hormone secretion in diabetes with high time-resolution and cell-specificity. Astrocytes respond to neuronal activity. However, whether astrocytic activity has any significance in brain function is unknown. Signaling pathway leading from astrocytes to neurons would be required for astrocytes to participate in neuronal functions and, here, we investigated the presence of such pathway. Optogenetics was used to manipulate astrocytic activity. A light-sensitive protein, channelrhodopsin-2 (ChR2), was selectively expressed in astrocytes. Photostimulation of these astrocytes induced glutamate release which modulated neuronal activity and animal behavior. Such glutamate release was triggered by intracellular acidification produced by ChR2 photoactivation. Astrocytic acidification occurs upon brain ischemia, and we found that another optogenetic tool, archaerhodopsin (ArchT), could counter the acidification and suppress astrocytic glutamate release. Controlling of astrocytic pH may become a therapeutic strategy upon ischemia. It is likely that arrhythmias should be avoided for therapies based on human pluripotent stem cell (hPSC)-derived cardiomyocytes (CM) to be effective. Towards achieving this goal, we introduced light-activated channelrhodopsin-2 (ChR2), a cation channel activated with 480 nm light, into human embryonic stem cells (hESC). By using in vitro approaches, hESC-CM are able to be activated with light. ChR2 is stably transduced into undifferentiated hESC via a lentiviral vector. Via directed differentiation, hESC(ChR2)-CM are produced and subjected to optical stimulation. hESC(ChR2)-CM respond to traditional electrical stimulation and produce similar contractility features as their wild-type counterparts but only hESC(ChR2)-CM can be activated by optical stimulation. Here it is shown that a light sensitive protein can enable in vitro optical control of hESC-CM and that this activation occurs optimally above specific light stimulation intensity and pulse width thresholds. For future therapy, in vivo optical stimulation along with optical inhibition could allow for acute synchronization of implanted hPSC-CM with patient cardiac rhythms.

Is the Prostate- Specific Antigen (PSA) test relevant only for prostate cancer?

No, although the PSA test can detect high levels of PSA that may indicate the presence of prostate cancer, many other conditions, such as an enlarged or inflamed prostate, can also increase PSA levels.

The aim of the present investigation was the evaluation of cost-effectiveness of variables used in monitoring patients with inoperable prostate cancer. Prostate-specific antigen (PSA), prostatic acid phosphatase (PAP), and radionuclide bone scan were considered. The tumor marker positivity was assessed according to dynamic criteria (> 50% increase between consecutive samples). 108 patients entered the study; 72 patients treated with a luteinizing hormone-releasing hormone analogue were followed up for periods ranging from 12 to 64 months. PSA and PAP levels were measured using immunometric assays. Both cutoff-based and dynamic, serial sample-based decision criteria were employed. With respect to a positive bone scan, PSA showed negative predictive values of 82 and 77%, respectively, using 4 and 10 ng/ml as cutoff points. Progression of the disease to the bone occurred in 20 patients: in 17 PSA was the first indicator of progression, in the other 3 PAP anticipated PSA for a very short time (3-4 months), which was not of relevance to clinical decisions. PAP is less specific and sensitive than PSA; PAP may eventually provide information on disease status in a limited percentage of patients with advanced prostate cancer treated with androgen ablation, being differently regulated with respect to PSA. No increasing PSA profile was detected in patients who responded to the therapy. From the results of the present investigation, we draw the following conclusions: (1) PSA can be used reliably as a unique tool in the follow-up of patients for the early detection of progressive disease, and (2) dynamic criteria of evaluation of serial PSA determinations probably provide more effective and earlier clinical information. We have assessed the feasibility of using fixed-limit criteria based on medical relevance and biological variation for evaluating the analytical performance of the prostate-specific antigen (PSA) test. The estimated within-subject variation of serum PSA is on the order of 10-20% at clinical decision points. The calculated performance goals of 5-10% CV are attainable with current immunoassay technology and agree with precision goals based on clinical experience and the current clinical use of the test. However, new clinical applications of PSA may require a degree of analytical performance that current methods may not be able to provide. The PSA model demonstrates the need for biologically based fixed-limit criteria for all tumor-marker tests. This study examined the clinical relevance of the determination of free PSA (f-PSA) in addition to total PSA (t-PSA). PATIENTS AND METHODS: Both total PSA- and free PSA-values of frozen sera obtained pretherapeutically from 80 patients with carcinoma (PC) and 171 patients with benign hyperplasia of the prostate (BPH) were analysed by means of PSA IRMA and FREE PSA IRMA (IMMUNOCORP/IBL). RESULTS: At 95% specificity (true negative test results), a cut-off value of 16.8 [micrograms/L] was obtained for total PSA (9 patients with BPH [5%] were above this value). For this cut-off value we calculated a sensitivity (true positive test results) of 41%. Using the same criteria for the ratio Q = f-PSA:t-PSA a cut-off of 0.083 was found again at a specificity of 95%. In a second step only patients with total PSA values below the cut-off level of 16.8 [micrograms/L]) were considered. Of these patients 11 of 160 with BPH (missing values = 1) and 13 of 33 with PC (missing values = 2) were below the above mentioned ratio (Q = 0.083). Considering both steps (total PSA and Q) 46 patients with PC were detected correctly and 20 patients with BPH would have been biopsied unnecessarily (positive biopsy rate: 70%). CONCLUSION: High total PSA levels are a very good indicator for the presence of prostate cancer. There is still concern to improve the differentiation between the diagnosis between BPH and PC, when an intermediate or low value (< or = 95% specificity) is observed. The determination of Q is only useful in this range and might be helpful for the clinician's decision to apply or avoid biopsy. We studied the methodical and clinical relevance of five determination assays for free PSA (f-PSA) in addition to the corresponding total PSA antigen (t-PSA). METHODS: Both the total PSA- and free-PSA-values of frozen sera obtained pretherapeutically from 80 patients with carcinoma (PC) and 171 patients with benign hyperplasia of the prostate (BPH) were analysed by means of Enzymun-Test PSA/BM, PSA-RIACT/ CIS, CanAg PSA EIA/ Dia, Tandem-E PSA/Hyb, PSA IRMA/ IBL and Enzymun-Test PSA free/BM, F PSA-RIACT/CIS, CanAg Anti Free PSA/Dia, Tandem-R free PSA/Hyb, FREE PSA IRMA/IBL. RESULTS: The coefficient of correlation between Hybritech PSA assay and the other assays was determined in patients with benign and maligt prostatic diseases. There was a strong overall correlation with all assays measuring total or free PSA, respectively. A satisfying correlation is also shown using a limited scale up to 50 ng/mL for total PSA and 5 ng/mL for free PSA. At 95% specificity sensitivities of total PSA between 40% and 50% of the ratio (Q) = free PSA/total PSA between 4% and 28% were calculated. In a second step only patients with total PSA values below the cutoff level of 16.5 [micrograms/l] (BM), 13.9 [micrograms/l] (CIS), 14.7 [micrograms/l] (Dia), 15.7 [micrograms/l] (Hyb) and 16.8 [micrograms/l] (IBL) were considered. Using the BM assays, of these patients 9 of 162 with BPH and 14 of 47 with PC [CIS: 14 of 162 with BPH and 4 of 48 with PC/Dia: 13 of 162 with BPH and 11 of 48 with PC/Hyb: 6 of 156 with BPH (missing values = 6) and 11 of 40 with PC/IBL: 11 of 160 with BPH (missing values = 1) and 13 of 33 with PC (missing values = 2)] were below the ratio Q = free PSA/total PSA. Considering both steps (total PSA and Q) using the BM assay 47 patlents with PC were detected correctly and 18 patients with BPH would have been biopsied unnecessarily (positive biopsy rate = pos. br.: 72%) [CIS: 38 patients with PC and 23 patients with BPH (pos. br.: 62%)/Dia: 43 patients with PC and 22 patients with BPH (pos. br.: 66%)/Hyb: 51 patients with PC and 15 patients with BPH (pos. br.: 77%)/IBL: 46 patients with PC and 20 patients with BPH (pos. br.: 70%)] CONCLUSIONS: High total PSA levels of all assays are a very good indicator for the presence of prostate cancer. There is still concern to improve the differentiation between BPH and PC, when an intermediate or low value (< 95% specificity) is observed. The determination of Q is only useful in this range and it might be helpful for the clinicians decision to apply or avoid biopsy. This study examined the clinical relevance of the determination of alpha 1-antichymotrypsin complexed PSA (ACT-PSA) in addition to total PSA antigen (t-PSA). PATIENTS AND METHODS: Both total PSA- and ACT-PSA-values of frozen sera obtained pretherapeutically from 93 patients with carcinoma (PC) and 132 patients with benign hyperplasia of the prostate (BPH) were analyzed by means of PSA sandwich-ELISA (Dianova GmbH) and ACT-PSA sandwich-ELISA (Dianova GmbH). RESULTS: At 95% specificity (true negative test results), a cutoff value of 18.9 [micrograms/L] was obtained for total PSA (7 patients with BPH [5%] were above this value). For this cutoff value we calculated a sensitivity (true positive test results) of 41%. Using the same criteria for the ratio Q = ACT-PSA: t-PSA (percentage of ACT-PSA) a cutoff of 6.0 was found again at a specificity of 95%. In a second step only patients with total PSA values below the cutoff level of 18.9 [micrograms/L]) were considered. Out of these patients 119 of 125 with BPH and 3 of 54 with PC were below the above mentioned ratio (Q = 6.0). Considering both steps (total PSA and Q) 42 patients with PC were detected correctly and 15 patients with BPH would have been biopsied unnecessarily. CONCLUSION: High total PSA levels are a very good indicator for the presence of prostate cancer. There is still concern to improve the differentiation of the diagnosis between BPH and PC, when an intermediate or low value (< or = 95% specificity) is observed. The determination of Q = ACT-PSA: t-PSA is not to be recommended because it might not be helpful for the clinicians decision to perform biopsy. This study examined the clinical relevance of the determination of free PSA (f-PSA) in addition to total PSA (t-PSA) in 6 study groups. PATIENTS AND METHODS: Both total PSA- and free PSA-values of sera samples obtained pretherapeutically from 455 patients with carcinoma (PCA) and 680 patients with benign hyperplasia of the prostate (BPH) were analyzed by means of Enzymun-Test PSA and Enzymun-Test Free PSA (Boehringer Mannheim GmbH, Germany). RESULTS: At 95% specificity (true negative test results), a cutoff value of 13.6 [micrograms/L] was obtained for total PSA (34 patients with BPH [5%] were above this value). For this cutoff value we calculated a sensitivity (true positive test results) of 44%. Using the same criteria for the ratio Q = f-PSA:t-PSA a cutoff of 0.13 was found again at a specificity of 95%. In a second step only patients with total PSA values below the cutoff level of 13.6 [micrograms/L]) were considered. Out of these patients 26 of 646 with BPH and 108 of 257 with PCA were below the above mentioned ratio (Q = 0.13). Considering both steps (total PSA and Q) 306 patients with PCA were detected correctly and 60 patients with BPH would have been biopsied unnecessarily. CONCLUSION: High total PSA levels are a very good indicator for the presence of prostate cancer. There is still concern to improve the differentiation of the diagnosis between BPH and PCA, when an intermediate or low value (< or = 95% specificity) is observed. The determination of the ratio is only useful in this range. It is more powerful at discriminating between PCA and BPH than t-PSA alone and may contribute to a reduction in unnecessary invasive techniques. OBJECTIVE: Current studies have proven that early, organ-confined stages of prostate cancer can be diagnosed through screening based on PSA levels, thus reducing cancer mortality. Here we report about our experience using an innovative one-step test for PSA in capillary blood. METHODS: The incubation time for a 50 microl blood sample with the indicator strip is 12 minutes until the qualitative visual results (<4.0 ng/ml or > or = 4 ng/ml) appear. In cooperation with urologists and accompanied by an extensive information campaign, the one-step test was made available free of charge to all men between the ages of 45 and 75 in all 28 pharmacies of our city (100,000 inhabitants). RESULTS: The test's acceptance rate among the 2,119 participants between the ages of 45 and 75 years amounted to 13.0%. Fifteen percent of all the tests conducted showed a positive PSA result (> or = 4 ng/ml). Prostate carcinoma was histologically confirmed in 14 (0.66%) of the men, nine times in the early stage (T2) and five times in the clinical stage (T3), corresponding to an incidence of circa 650 cases per 100,000 men in the target age group. CONCLUSIONS: This newly developed PSA test system can enhance the acceptance rate and effectiveness of medical check-ups for prostate cancer, because it is easy-to-use, cost-effective and accurate (specificity 81.3%, sensitivity 91.1%). The test should be always conducted by an experienced physician or pharmacist. It is not a substitute for a regular physical examination (DRE, TRUS, biopsy...). CONTEXT: Routine cancer screening with prostate-specific antigen (PSA) is controversial, and practice guidelines recommend that men be counseled about its risks and benefits. OBJECTIVE: To evaluate the process of decision making as men react to and use information after PSA counseling. DESIGN: Written surveys and semistructured qualitative interviews before and after a neutral PSA counseling intervention. PARTICIPANTS: Men 40 to 65 years of age in southeastern Michigan were recruited until thematic saturation--that is, the point at which no new themes emerged in interviews (n = 40). RESULTS: In a paper survey, 37 of 40 participants (93%) said that they interpreted the counseled information as unfavorable toward PSA. However, 30 participants (75%) said after the intervention that they intended to be tested in the future, including 29 of 30 men (97%) with prior PSA testing. In the interview, many participants cited underlying beliefs as a reason to dismiss the counseled information. Qualitative analysis found the seven most common beliefs cited were fear of cancer, relevance of salient anecdotes and analogies, distrust of statistics, enthusiasm for "prevention," protection from "bad luck," faith in science, and valuing PSA as knowledge for its own sake. Although some beliefs could be interpreted as judgment errors, most were credible on a personal level. CONCLUSIONS: Most men who underwent PSA counseling cited underlying beliefs rather than the content of counseled information as the basis for their decisions regarding future PSA screening. If widespread, such beliefs may render clinician counseling and decision support methods less effective. Eliciting patient beliefs prior to counseling may improve the shared decision-making process. BACKGROUND: Rapid uptake of prostate-specific antigen (PSA) testing has occurred in the United States despite inconclusive evidence regarding mortality benefit. METHODS: We examined data (n=927) from the 2003 Health Information National Trends Survey to assess prevalence of self-reported PSA use and its association with patients' decision making. RESULTS: Over half (55.2%) the sample reported ever having had a PSA test. Men aged 65-74 (OR=2.53, 1.49-4.31), with some college (OR=2.41, 1.22-4.77) or college degrees (OR=5.01, 2.53-9.90) were more likely to have had PSA tests, while men without health insurance (OR=0.32, 0.12-0.88) or a usual source of care (OR=0.35, 0.22-0.54) were less likely. In a model including healthcare provider communication and information seeking, men who reported that providers involved them in decisions (OR=1.76, 1.02-3.03) and recommended PSA (OR=236.3, 70.5-791.4) were more likely to have had the tests. Men aged 65-74 (OR=2.30, 1.33-4.00), with college degrees (OR=2.91, 1.45-5.82), and greater information attention/seeking (OR=1.23, 1.07-1.40) were more likely to report PSA recommendations, while those without usual care were less likely (OR=0.37, 0.22-0.64). Men without usual care (OR=0.38, 0.20-0.71) and Hispanic men (OR=0.40, 0.19-0.85) were less likely to report that healthcare providers involved them in healthcare decisions. CONCLUSIONS: Results emphasize the relevance of patient decision making and the importance of healthcare providers in PSA testing. This article has discussed the increased incidence and disproportionately increased mortality of prostate cancer among African American men.Although the exact reasons are unknown, genetics may play a role, in addition to health care practices. Morbidity from other disease states, such as diabetes, obesity, or hypertension, may influence the overall survival of patients with prostate cancer. Current research tools will continue to explore biologic differences between the races; however, socioeconomic status and access to health care must not be overlooked. Several studies have demonstrated that similar disease stages and equal access to health care will result in similar outcomes. It is recognized that screening for prostate cancer will remain a controversial topic. Several influential professional societies recommend against screening and other professional societies endorse screening. Large-scale trials are currently underway hoping to answer this critical question. Since the advent of current screening tools, however, it seems that the overall mortality for prostate cancer has decreased and this cannot be ignored. Certainly, screening programs and clinical trials have traditionally had difficulty in recruiting minority participants, although more recent trials seem to be finding success. A primary care physician who is viewed as competent by their patients can certainly have a positive impact on their African American patients' willingness to participate in studies and screening programs. Most importantly, on the individual level, primary care physicians can provide a great service to their minority patients by offering educational materials on prostate cancer and by offering screening to qualified patients. The current American Urologic Association and National Cancer Institute guidelines recommend offering screening to all men age 50 and above. African American men or men with a first-degree relative with prostate cancer should be offered screening beginning at age 40. Proper screening consists of both a digital rectal examination to assess for asymmetry or nodules of the prostate and a serum PSA. Current recommendations are that individuals with a serum PSA greater than 4 ng/mL ora prostate nodule or asymmetric prostate should be referred to an urologist,where a biopsy can be performed easily in the office setting.The PSA cutoff of 4 has recently been questioned. A study by Thompson et al [31] evaluated 2950 men with a PSA of 4 or less with prostate biopsy.They found that the risk of prostate cancer in men with a PSA between 3.1 and 4 was 26.9% and that 25% of these men with prostate cancer had high-grade disease. All men found to have cancer had T1 disease. The clinical relevance of this surprisingly high rate of prostate cancer in men with a normal PSA is yet to be determined and is pending in studies on the ultimate effect of screening on mortality from prostate cancer. This information is not intended to confuse the issue, but intended to provide the most up-to-date information and allow for the best clinical decision making by the primary care physician. What can currently be recommended is if a patient is concerned about his possibility of having prostate cancer despite a normal PSA, a referral to an urologist to at least further discuss the issue may be in order. This may be especially true if the patient is African American or has a family history of prostate cancer at an early age. OBJECTIVE: To assess the reliability of a new measurement of prostate-specific antigen (PSA) using a blotting-paper assay (otest) compared to the standard PSA immunoassay. SUBJECTS AND METHODS: The PSA level was measured in 205 men volunteers (median age 70 years, range 41-75) using a otest and a standard PSA immunoassay, collected at the same time; 30 microL of capillary blood placed on to a blotting paper were collected for the otest and sent by mail to the same laboratory for the two assays. The results were compared statistically using the Spearman test, the intraclass correlation coefficient and the Bland-Altman test. RESULTS: The otest threshold for an abnormal PSA level was 78 pg/mL, which corresponded to a standard PSA value of 3 ng/mL, with a sensitivity of 100%. There was a significant correlation (r = 0.98, Spearman test; P < 0.001) between the otest and the standard PSA assay. The intraclass correlation coefficient was 0.87. The Bland-Altman test showed a good agreement between the otest and the standard PSA assay, but there was an increasing proportional difference with increasing PSA value. CONCLUSION: There was a very high correlation between the otest and the standard PSA assay, especially for standard PSA levels of <5 ng/mL. Economic and clinical studies are indicated to confirm the utility of the otest in organized mass screening of prostate cancer. INTRODUCTION: Information on prostate diseases, including prostate cancer, has been promoted by the Association Française d'Urologie (AFU) for several years, but is developing slowly in France. In 2005, a first communication was targeted to the male public and identified the reasons for the fatalistic attitude of men, and paradoxically, why the prostate incarnates the vulnerability of their sexual capital. As part of a second phase, this article presents the results of a complementary study conducted among general practitioners to identify their expectations and the most appropriate levers to promote screening. MATERIAL AND METHOD: The Ipsos survey company developed a Krisis qualitative protocol in October 2005 (after the first French prostate day on 15 September 2005). Three groups of general practitioners were defined: doctors who are very active in terms of screening, doctors who are uncomfortable with this problem and doctors who systematically refer their patients to urologists. RESULTS: The management of prostate diseases often highlights the ageing process for the patient. The ability to discuss these problems during the consultation depended on the doctor's degree of comfort with this subject, which is related to his/her training and relationships with urologists. To initiate the question of screening, general practitioners involved in this process asked simple questions about everyday practices without being afraid of making jokes or basing their approach on mediatization of the disease. Digital rectal examination is one of the important clinical elements but is not always easy to perform. PSA was found to be an examination that is not always appropriate, characterized by a lack of information on the conditions for ordering this test, its usefulness and its relevance for screening. Ultrasound could be a way of alerting the patient without dramatizing the situation, letting the urologist perform digital rectal examination. Female general practitioners preferred PSA and ultrasound. The doctors surveyed relied on mediatization of prostate diseases, a high level of interactivity with urologists and documents and brochures to be placed in waiting rooms to relay screening messages. CONCLUSION: General practitioners need their authorities, specialists and public health institutions to develop and mediatize andrology in the same way as gynaecology. Urologists play a major supportive role by means of conferences, postgraduate training or AFU invitations. OBJECTIVES: To determine whether combining short-term neoadjuvant androgen deprivation therapy (NADT) with high-intensity focused ultrasound (HIFU) had a significant benefit in a large population of men with nonmetastatic prostate cancer (CaP). METHODS: We evaluated the records of 530 patients whose prostate-specific antigen (PSA) level at diagnosis was 30 ng/mL or less and whose follow-up period was not less than 12 months, at seven investigational sites. Two hundred seventy patients had received NADT (within 6 months), and 260 had not. The primary outcome measure was disease-free survival according to the combined criteria satisfying the Phoenix definition (less than nadir + 2), negative prostate biopsy, and no findings of distant metastasis after the last HIFU treatment. The significance of the differences of values or the distributions of each parameter between two groups was evaluated with a Mann-Whitney U test, unpaired t test, or chi-square test, and a multivariate Cox proportional hazards model was used to evaluate the prognostic relevance of preoperative parameters. RESULTS: Statistical analyses showed that the NADT group had worse disease (higher PSA and risk group) than the HIFU-only group. Variables shown by multivariate analyses to be significant prognostic parameters were pretreatment PSA level, clinical stage, and no use of NADT. Short-term NADT significantly improved the 3-year disease-free survival rate of patients with intermediate-risk and high-risk CaP. During follow-up the frequencies of complications did not differ significantly with or without NADT. CONCLUSIONS: Our retrospective study suggests that combining short-term NADT with HIFU treatment is of significant clinical benefit to intermediate-risk and high-risk CaP patients without increasing the likelihood of complications. BACKGROUND: No studies have examined medical students' recommendation and use of prostate-specific antigen (PSA) testing and digital rectal exam (DRE) to screen for prostate cancer. We hypothesized that students' race and extent of training on these techniques would be associated with their administration of them. METHODS: We analyzed multiinstitutional longitudinal data from a cohort of 2181 medical students in the class of 2003. We queried students' health behavior, their knowledge of prostate cancer racial disparities, their frequency of performing a PSA test or a DRE on a man 50 years of age or older (senior year only), the perceived relevance of such services to their future practice, and their training on PSA and DRE. We examined predictors of students' administering PSA and DRE tests to patients during the senior year and changes in the predictors over time. RESULTS: Respectively, 27% and 34% of students reported using the PSA and DRE "usually/always" during their senior year. Black students reported administering the PSA test more often than did students of other races, but race was not a significant predictor of PSA screening after controlling for personal healthy behavior. High perceived relevance to future practice and extensive training on PSA were most strongly associated with administration of PSA. CONCLUSIONS: The association between healthy personal behavior and PSA administration confounded the association between race and PSA screening. These results may help explain differences in prostate cancer screening among physicians and help medical educators tailor their curricula on prostate cancer screening. OBJECTIVES: To evaluate the relevance of demographic, physician, and psychological characteristics to PSA screening in ethnic subpopulations and ascertain whether the same characteristics distinguish men who have never had a PSA from those who screen infrequently and those who screen yearly (adhere). DESIGN AND METHODS: Stratified cluster-sampling was used to recruit 533 men (45-70 years) from four ethnic groups: African-American; European-American; immigrant Jamaican; and immigrant men from Trinidad and Tobago. Men provided demographic and structural (insurance, regular physician, annual exam, and physician recommendation), cognitive (risk and efficacy perceptions, knowledge), and emotional variables (cancer worry and embarrassment), and reported on PSA screening history. Multinomial logistic regression used these variables to predict three screening classifications (never screened, partially adherent, and adherent). RESULTS: Multinomial logistic regression showed that minority men were less likely to report either never screening or yearly screening, while younger men were more likely. Lack of a regular physician (OR=2.87, 95% CI 1.39-5.84), an annual exam (OR=1.73, 95% CI 0.91-3.28), and low recommendation (OR=3.76, 95% CI 2.13-6.66) were associated with being categorized as a never (vs. partially adherent) screener, but only annual exam (OR=0.26, 95% CI 0.10-0.63) was associated with yearly screening. Lower cancer worry was marginally associated with never screening (OR=0.59, 95% CI 0.38-1.04), while knowledge was associated with screening yearly over time (OR=0.46, 95% CI 0.28-0.77). CONCLUSIONS: Demographic, physician, and psychological variables are differentially associated with never, less than yearly, and yearly screening classifications. Minority men were unlikely to have never screened, but were also less likely to screen yearly. Physician variables were associated with the difference between not screening and partially adherent, but not between partially adherent and yearly screening suggesting that the role of physicians in PSA behaviour over time would benefit from further study. This study explored older men's and their partners' reactions to a television news program on the medical debate surrounding the use of the prostate-specific antigen (PSA) test for prostate cancer screening. Six focus groups, split by gender and socio-economic status (SES), were conducted with men aged 50 years or older (n = 28) and female partners of such men (n = 13). A self-completion questionnaire was also used to yield quantitative indices. In general, viewers appeared to appreciate from the debate that there was controversy surrounding prostate cancer screening, and they recognized that PSA testing is more applicable to certain subgroups of men. Although there were differences by SES and gender, the results suggest that exposing health consumers to medical uncertainty and "expert" conflict can help raise awareness of the issue and complexities involved. However, there was evidence to suggest that health consumers may be better able to negotiate conflicting medical information if the different sides of the argument are plainly noted and a clear distinction is made between opinion and evidence. This study has broader relevance to the management of media coverage of medical controversies by public health organizations. The deficiencies of serum PSA as a prostate-cancer-specific diagnostic test are well recognized. Thus, the development of novel biomarkers for prostate cancer detection remains an important and exciting challenge. Noninvasive urine-based tests are particularly attractive candidates for large-scale screening protocols, and biomarker discovery programs using urine samples have emerged for detecting and predicting aggressiveness of prostate cancer. Some new biomarkers already outperform serum PSA in the diagnosis of this disease. Currently, the PCA3 (prostate cancer antigen 3) urine test is probably the best adjunct to serum PSA for predicting biopsy outcome, and has proven its clinical relevance by surpassing the predictive abilities of traditional serum biomarkers. New research methods are also emerging, and high-throughput technologies will facilitate high-dimensional biomarker discovery. Future approaches will probably integrate proteomic, transcriptomic and multiplex approaches to detect novel biomarkers, and aim to identify combinations of multiple biomarkers to optimize the detection of prostate cancer. In addition, an unmet need remains for markers that differentiate indolent from aggressive cancers, to better inform treatment decisions. IMPORTANCE: To make good decisions about prostate-specific antigen (PSA) screening, men must consider how they value the different potential outcomes. OBJECTIVE: To determine the effects of different methods of helping men consider such values. DESIGN AND SETTING: Randomized trial from October 12 to 27, 2011, in the general community. PARTICIPANTS: A total of 911 men aged 50 to 70 years from the United States and Australia who had average risk. Participants were drawn from online panels from a survey research firm in each country and were randomized by the survey firm to 1 of 3 values clarification methods: a balance sheet (n = 302), a rating and ranking task (n = 307), or a discrete choice experiment (n = 302). INTERVENTION: Participants underwent a values clarification task and then chose the most important attribute. MAIN OUTCOME MEASURES: The main outcome was the difference among groups in the most important attribute. Secondary outcomes were differences in unlabeled test preference and intent to undergo screening with PSA. RESULTS: The mean age was 59.8 years; most participants were white and more than one-third had graduated from college. More than 40% reported a PSA test within 12 months. The participants who received the rating and ranking task were more likely to report reducing the chance of death from prostate cancer as being most important (54.4%) compared with those who received the balance sheet (35.1%) or the discrete choice experiment (32.5%) (P < .001). Those receiving the balance sheet were more likely (43.7%) to prefer the unlabeled PSA-like option (as opposed to the "no screening"-like option) compared with those who received rating and ranking (34.2%) or the discrete choice experiment (20.2%). However, the proportion who intended to undergo PSA testing was high and did not differ between groups (balance sheet, 77.1%; rating and ranking, 76.8%; and discrete choice experiment, 73.5%; P = .73). CONCLUSIONS AND RELEVANCE: Different values clarification methods produce different patterns of attribute importance and different preferences for screening when presented with an unlabeled choice. Further studies with more distal outcome measures are needed to determine the best method of values clarification, if any, for decisions such as whether to undergo screening with PSA.

List symptoms of Hakim Triad.

Triad of Hakim--Adams is well known for normal pressure hydrocephalus (NPH): dementia, gait disturbances and urinary incontinence.

Three patients with normal pressure hydrocephalus and Parkinson's disease are reported. The recognition of this association is important because these two entities require specific therapeutic approaches. The presence of Parkinson's disease does not preclude an excellent response of the hydrocephalus to a shunting procedure. Although several reports of cases with the characteristic clinical manifestations of normal pressure hydrocephalus--progressive dementia, gait difficulty and urinary incontinence--have been published earlier, it was Adams and Hakim who emphasized the clinical triad and the effect of shunting the cerebrospinal fluid as a means of treatment. Messert and Baker stressed that the gait disturbance had a close resemblance to the freezing gait of parkinsonism. We are reporting three patients who had both conditions. Recognition of the existence of both disorders in the same patients is important since appropriate treatment of each of them led to marked improvement of their symptoms. BACKGROUND: Chronic (normotensive or low pressure) hydrocephalus is characterized clinically by gait disturbance, cognitive and urinary impairment, known as Hakim's triad. Nothing has been reported about impairment in sexual function, which could involve both the patient and the patient's partner. METHODS: Out of 97 patients undergoing shunt placement for chronic hydrocephalus, 28 male patients (28.8%) referenced sexual dysfunction before operation. In these cases, we performed a preoperative and postoperative survey of sexual activity. RESULTS: In the preoperative period, all 28 patients reported having no sexual activity or arousal, from 2 to 4 years before the operation. Following shunt placement, 22/28 (78.5%) of patients regained variable sexual desire within a period ranging from 3 to 8 weeks, affording normal sexual activity with their partner. CONCLUSIONS: Sexual dysfunction can be part of the very early clinical background in patients with Hakim's triad and neuroradiological imaging compatible with chronic hydrocephalus. Restoration of sexual ability and arousal should be considered among the postoperative goals in these cases, together with improvements in cognition, gait, and urinary continence. Triad of Hakim--Adams is well known for normal pressure hydrocephalus (NPH): dementia, gait disturbances and urinary incontinence. Variability of intensity of these symptoms is obvious. However in clinical practice all classic signs are present. We describe a case of posttraumatic NPH producing only gait impairment with intact intellect and memory and bladder function. Such reports were not found in literature.

Which is the cellular target of gefitinib?

The specific cellular target of Gefitinib (Iressa) is the epidermal growth factor receptor (EGFR).

Gefitinib is a specific inhibitor of the epidermal growth factor receptor (EGFR) that causes growth delay in cancer cell lines and human tumor xenografts expressing high levels of EGFR. An understanding of the downstream cellular targets of gefitinib will allow the discovery of biomarkers for predicting outcomes and monitoring anti-EGFR therapies and provide information for key targets for therapeutic intervention. In this study, we investigated the role of FOXO3a in gefitinib action and resistance. Using two gefitinib-sensitive (i.e., BT474 and SKBR3) as well as three other resistant breast carcinoma cell lines (i.e., MCF-7, MDA-MB-231, and MDA-MB-453), we showed that gefitinib targets the transcription factor FOXO3a to mediate cell cycle arrest and cell death in sensitive breast cancer cells. In the sensitive cells, gefitinib treatment causes cell cycle arrest predomitly at the G(0)-G(1) phase and apoptosis, which is associated with FOXO3a dephosphorylation at Akt sites and nuclear translocation, whereas in the resistant cells, FOXO3a stays phosphorylated and remains in the cytoplasm. The nuclear accumulation of FOXO3a in response to gefitinib was confirmed in tumor tissue sections from breast cancer patients presurgically treated with gefitinib as monotherapy. We also showed that knockdown of FOXO3a expression using small interfering RNA (siRNA) can rescue sensitive BT474 cells from gefitinib-induced cell-proliferative arrest, whereas reintroduction of active FOXO3a in resistant MDA-MB-231 cells can at least partially restore cell-proliferative arrest and sensitivity to gefitinib. These results suggest that the FOXO3a dephosphorylation and nuclear localization have a direct role in mediating the gefitinib-induced proliferative arrest and in determining sensitivity to gefitinib. Gefitinib (Iressa) is a specific and effective epidermal growth factor receptor inhibitor. An understanding of the downstream cellular targets of gefitinib will allow the discovery of biomarkers for predicting outcomes and monitoring anti-epidermal growth factor receptor therapies and provide information for overcoming gefitinib resistance. In this study, we investigated the role and regulation of FOXM1 in response to gefitinib treatment in breast cancer. Using the gefitinib-sensitive breast carcinoma cell lines BT474 and SKBR3 as well as the resistant lines MCF-7, MDA-MB-231, and MDA-MB-453, we showed that gefitinib represses the expression of the transcription factor FOXM1 in sensitive, but not resistant, cells. FOXM1 repression by gefitinib is associated with FOXO3a activation and is mediated at the transcriptional level and gene promoter level. These results were verified by immunohistochemical staining of biopsy samples from primary breast cancer patients obtained from a gefitinib neoadjuvant study. We also showed that ectopic expression of an active FOXO3a represses FOXM1 expression, whereas knockdown of FOXO3a expression using small interfering RNA can up-regulate FOXM1 and its downstream targets polo-like kinase, cyclin B1, and CDC25B and rescue sensitive BT474 cells from gefitinib-induced cell proliferative arrest. These results suggest that gefitinib represses FOXM1 expression via FOXO3a in breast cancer. We further showed that overexpression of a wild-type FOXM1 or a constitutively active FOXM1, DeltaN-FOXM1, abrogates the cell death induced by gefitinib, indicating that FOXM1 has a functional role in mediating the gefitinib-induced proliferative arrest and in determining sensitivity to gefitinib. In summary, our study defined FOXM1 as a cellular target and marker of gefitinib activity in breast cancer. Gefitinib, the specific inhibitor of the epidermal growth factor receptor (EGFR), may cause growth delay in cancer cell lines. Thorough understanding of the downstream cellular signaling of gefitinib will facilitate the discovery of biomarkers for predicting outcomes and monitoring anti-EGFR therapies, and provide information for key targets for therapeutic intervention. In this study, we investigated the role of transducer of erbB2.1 (TOB1) in gefitinib therapy. Using the lung carcinoma cell lines A549 and NCI-H1975, the results suggested that gefitinib might mediate cell cycle arrest in lung cancer cells at least by targeting TOB1 expression. Gefitinib treatment caused cell cycle arrest predomitly at the G1 phase, which is associated with TOB1 nuclear translocation and its interaction with cyclin D1. We also showed that knockdown of TOB1 expression by RNAi rescued lung cancer cells from gefitinib-induced cell-proliferative arrest. These results suggest that TOB1 interaction with cyclin D1 and nuclear translocation is directly involved in the gefitinib-induced anti-proliferative cell cycle arrest.

What kind of bonds are connecting keratin molecules?

cystine disulfide bonds amide bonds hydrogen bonds

Hair is composed of proteins, lipids, water, and small amounts of trace elements. All proteins in animal and human bodies are built from permutations of amino acid molecules in a polypeptide string. The polypeptide chains of protein keratin are organized into filaments in hair cells. Hair is one of the most difficult proteins to digest or solubilize. Among the most common dissolving procedures for hair are acidic, alkaline, and enzymatic hydrolysis. For the analysis of hair, the solid samples are transferred by solubilization via digestion into a liquid phase. Small molecular solvents and molecules with hydrophobic groups appear to have higher affinity for hair. A good solvent attacks the disulfide bonds between cystine molecules and hydrates the hair shaft. Consequently, the hair becomes a jelly-like mass. X-rays interact strongly with biological organisms. Synchrotron radiation sources deliver very intense X-ray photon fluxes within micro- or submicro cross-section beams, resulting in doses larger than the MGy. The relevance of synchrotron radiation analyses of biological materials is therefore questionable since such doses, million times higher than the ones used in radiotherapy, can cause huge damages in tissues, with regard to not only DNA, but also proteic and lipid organizations. Very few data concerning the effect of very high X-ray doses in tissues are available in the literature. We present here an analysis of the structural phenomena which occur when the model tissue of human hair is irradiated by a synchrotron X-ray micro-beam. The choice of hair is supported by its hierarchical and partially ordered keratin structure which can be analysed inside the tissue by X-ray diffraction. To assess the damages caused by hard X-ray micro-beams (1 microm(2) cross-section), short exposure time scattering SAXS/WAXS patterns have been recorded at beamline ID13 (ESRF) after various irradiation times. Various modifications of the scattering patterns are observed, they provide fine insight of the radiation damages at various hierarchical levels and also unexpectedly provide information about the stability of the various hierarchical structural levels. It appears that the molecular level, i.e. the alpha helices which are stabilized by hydrogen bonds and the alpha-helical coiled coils which are stabilized by hydrophobic interactions, is more sensitive to radiation than the supramolecular architecture of the keratin filament and the filament packing within the keratin associated proteins matrix, which is stabilized by disulphide bonds. Hair keratin is a composite structure in which intermediate filaments (IF) are embedded in a protein matrix. During the early stages of development in the hair follicle the redox potential is such that the cysteine residues in the IF are maintained in a reduced form. However, at a late stage of development the redox potential changes to produce an oxidizing environment and the IF undergo a structural transition involving both molecular slippage and radial compaction. In our earlier study the changes in the molecular parameters were estimated from knowledge of the sites of artificially induced crosslinks, and it was noted that the changes in these parameters realigned many of the cysteine residues to positions more favorable to disulfide bond formation. As the energy involved in the formation of disulfide bonds is much greater than that of hydrogen bonds or van der Waals interactions the structural transition is likely to be dominated by the requirement that the bonded cysteine residues occur at closely equivalent axial positions. This criterion was used in the present study to obtain more precise values for the molecular parameters in the oxidized fiber than has hitherto been possible. A comparison of the sequences of hair keratins and epidermal keratins suggests that the slippage observed in trichocyte IF during keratinization does not occur in epidermal IF. There is as yet no high-resolution data regarding the structure and organization of keratin intermediate filaments, which are obligate heteropolymers providing vital mechanical support in epithelia. We report the crystal structure of interacting 2B regions from the central coiled-coil domains of keratins 5 and 14 (K5 and K14), expressed in progenitor keratinocytes of epidermis. The interface of the K5-K14 coiled-coil heterodimer has asymmetric salt bridges, hydrogen bonds and hydrophobic contacts, and its surface exhibits a notable charge polarization. A trans-dimer homotypic disulfide bond involving Cys367 in K14's stutter region occurs in the crystal and in skin keratinocytes, where it is concentrated in a keratin filament cage enveloping the nucleus. We show that K14-Cys367 impacts nuclear shape in cultured keratinocytes and that mouse epidermal keratinocytes lacking K14 show aberrations in nuclear structure, highlighting a new function for keratin filaments. Mats of wool-derived keratin ofibre have been prepared by electrospinning solutions of keratin in formic acid at 20 and 15 wt.%, and obtaining ofibres with mean diameter of about 400 and 250 nm, respectively. These mats can find applications in tissue engineering (they can mimic the native extracellular matrix) and in wastewater treatment (they can trap small particles and adsorb heavy-metals). A drawback to overcome is their solubility in water. A stabilization method, based on a thermal treatment alternative to the use of formaldehyde, is proposed. The solubility test in the dithiothreitol/urea extraction buffer, the amino acid composition analysis and studies on keratin secondary structures suggest that the improved stability in water of thermally treated mats can be ascribed to the formation of amide bonds between acid and basic groups of some amino acid side chains. The differentiation of the corneous layers of lizard epidermis has been analyzed by ultrastructural immunocytochemistry using specific antibodies against alpha-keratins and keratin associated beta-proteins (KAbetaPs, formerly indicated as beta-keratins). Both beta-cells and alpha-cells of the corneous layer derive from the same germinal layer. An acidic type I alpha-keratin is present in basal and suprabasal layers, early differentiating clear, oberhautchen, and beta-cells. Type I keratin apparently disappears in differentiated beta- and alpha-layers of the mature corneous layers. Conversely, a basic type II alpha-keratin rich in glycine is absent or very scarce in basal and suprabasal layers and this keratin likely does not pair with type I keratin to form intermediate filaments but is weakly detected in the pre-corneous and corneous alpha-layer. Single and double labeling experiments show that in differentiating beta-cells, basic KAbetaPs are added and replace type-I keratin to form the hard beta-layer. Epidermal alpha-keratins contain scarce cysteine (0.2-1.4 %) that instead represents 4-19 % of amino acids present in KAbetaPs. Possible chemical bonds formed between alpha-keratins and KAbetaPs may derive from electrostatic interactions in addition to cross-linking through disulphide bonds. Both the high content in glycine of keratins and KAbetaPs may also contribute to increase the hydrophobicy of the beta- and alpha-layers and the resistance of the corneous layer. The increase of gly-rich KAbetaPs amount and the bonds to the framework of alpha-keratins give rise to the inflexible beta-layer while the cys-rich KAbetaPs produce a pliable alpha-layer. This paper introduces a new approach for immobilizing a quaternary ammonium moiety on a keratinous substrate for enhanced medical applications. The method involves the generation of thiols by controlled reduction of cystine disulfide bonds in the keratin, followed by reaction with [2-(acryloyloxy)ethyl]trimethylammonium chloride through thiol-ene click chemistry. The modified substrate was characterized with Raman and infrared spectroscopy, and assessed for its antibacterial efficacy and other performance changes. The results have demonstrated that the quaternary ammonium moiety has been effectively attached onto the keratin structure, and the resultant keratin substrate exhibits a multifunctional effect including antibacterial and antistatic properties, improved liquid moisture management property, improved dyeability and a non-leaching characteristic of the treated substrate.

Is autism one of the characteristics of Moebius syndrome?

Moebius syndrome is a rare congenital disorder usually defined as a combination of facial weakness with impairment of ocular abduction. A strong association of Moebius syndrome with autism spectrum disorders (ASDs) has been suggested in early studies with heterogenous age groups.

Fifty-nine cases with infantile autism/autistic disorder were subclassified according to associated medical condition (fragile-X, tuberous sclerosis, neurofibromatosis, hypo-melanosis of Ito, Moebius syndrome, Rett syndrome, and a 'new' syndrome associated with a marker chromosome). It was concluded that, even within a group of cases fitting currently accepted criteria for autism, there is considerable variation in symptom profile depending on the exact type of associated medical condition. Seventeen children and young adults with Moebius syndrome were examined with a view to finding symptoms of autism. Some 40% of the group showed all or many of the symptoms typical of autistic disorder. The high frequency of autistic symptoms in Moebius syndrome might be a marked overrepresentation and could be suggestive of a common underlying neurobiological deficit at the brainstem level. INTRODUCTION AND DEVELOPMENT: In this study we report on the different genetic syndromes in which autism has been described as one of the possible manifestations. CONCLUSIONS: Certain genetic syndromes are providing us with extremely valuable information about the role played by genetics in autism. This is the case of the following syndromes: Angelman syndrome, Prader-Willi syndrome, 15q11-q13 duplication, fragile X syndrome, fragile X premutation, deletion of chromosome 2q, XYY syndrome, Smith-Lemli-Opitz syndrome, Apert syndrome, mutations in the ARX gene, De Lange syndrome, Smith-Magenis syndrome, Williams syndrome, Rett syndrome, Noo syndrome, Down syndrome, velo-cardio-facial syndrome, myotonic dystrophy, Steinert disease, tuberous sclerosis, Duchenne's disease, Timothy syndrome, 10p terminal deletion, Cowden syndrome, 45,X/46,XY mosaicism, Myhre syndrome, Sotos syndrome, Cohen syndrome, Goldenhar syndrome, Joubert syndrome, Lujan-Fryns syndrome, Moebius syndrome, hypomelanosis of Ito, neurofibromatosis type 1, CHARGE syndrome and HEADD syndrome. Moebius sequence is a rare congenital disorder usually defined as a combination of facial weakness with impairment of ocular abduction. It is questionable, whether there is a strong association of the sequence with autism spectrum disorders (ASDs) as suggested in some earlier case reports and studies. Twenty-two participants with Möbius sequence aged 6-16 years followed a request of the German Moebius foundation to participate in a nationwide study. All patients had a physical examination and intelligence testing. Primary caregivers were asked to complete two screening measures of ASD (Behaviour and Communication Questionnaire, VSK; Marburger Asperger's Syndrome Rating Scale, MBAS). For those who reached the cut-off for ASD and/or showed behavioural aspects indicative of ASDs during IQ testing and/or physical examination, well standardized diagnostic instruments (Autism Diagnostic Interview-Revised, Autism Diagnostic Observation Schedule, and Kinder-DIPS) were administered. Minimal diagnostic criteria for Möbius sequence were congenital facial weakness (uni- or bilateral) and impairment of ocular abduction (uni- or bilateral). Three boys (one of them mentally retarded) out of 22 participants (12 males and 10 females) were found suspicious of ASD by screening, but none of them fulfilled diagnostic criteria of ASD on a clinical consensus conference. Therefore, ASDs seem to be not as frequent as reported in previous studies on patients with Möbius sequence. The diagnosis of Moebius syndrome, a rare congenital disorder, is primarily based on congenital facial and abducent nerve palsy. Involvement of other cranial nerves is also common. Occasionally the V, X, XI, and XII cranial nerves are involved, resulting in a difficulty to chew, swallow, and cough, which often leads to respiratory complications. Mental retardation and autism have been reported in some cases. Moebius syndrome can be associated with orofacial anomalies and limb malformations. The authors describe a patient with a confirmed diagnosis of Moebius syndrome associated with hydrosyringomyelia. No case of Moebius syndrome involving primarily the spinal cord has been reported so far. This patient did not present with other factors directly linked to syringomyelia.

Is Sarcolipin a regulatory/inhibitory protein of the Calcium ATPase SERCA?

Sarcolipin (SLN) is a 3 kD membrane protein found in sarcoplasmic reticulum (SR) and it is a newly identified regulator of the sarco/endoplasmic reticulum Ca(2+)-ATPase (Serca) pump. SLN inhibits sarcoplasmic reticulum Ca(2+) ATPase (SERCA) activity and reduces its affinity of Ca(2+), resulting in dysfunction of myocardial contraction and heart failure. Sarcolipin is a key regulator of SERCA2a in atria.

Sarcolipin (SLN) is an inhibitor of sarco(endo)plasmic reticulum Ca(2+)-ATPases (SERCAs) in vitro, but its function in vivo has not been defined. NF-SLN cDNA (SLN tagged N-terminally with a FLAG epitope) was introduced into rat soleus muscle in one hindlimb by plasmid injection and electrotransfer. Western blotting showed expression and co-immunoprecipitation showed physical interaction between NF-SLN and SERCA2a. Contractile properties and SERCA2a function were assessed and compared with vector-injected contralateral soleus muscles. NF-SLN reduced both peak twitch force (P(t)) (123.9 +/- 12.5 versus 69.8 +/- 8.9 millinewtons) and tetanic force (P(o)) (562.3 +/- 51.0 versus 300.7 +/- 56.9 millinewtons) and reduced both twitch and tetanic rates of contraction (+dF/dt) and relaxation (-dF/dt) significantly. Repetitive stimulation (750-ms trains at 50 Hz once every 2 s for 3 min) showed that NF-SLN increased susceptibility to fatigue. These changes in contractile function were observed in the absence of endogenous phospholamban, and NF-SLN had no effect on either SERCA2a or SERCA1a expression levels. NF-SLN also decreased maximal Ca(2+) transport activity at pCa 5 by 31% with no significant change in apparent Ca(2+) affinity (6.36 +/- 0.07 versus 6.39 +/- 0.08 pCa units). These results show that NF-SLN expression impairs muscle contractile function by inhibiting SERCA function and diminishing sarcoplasmic reticulum Ca(2+) stores. Sarcolipin (SLN) and phospholamban (PLN) are effective inhibitors of the sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA). These homologous proteins differ at their N and C termini: the C-terminal Met-Leu-Leu in PLN is replaced by Arg-Ser-Tyr-Gln-Tyr in SLN. The role of the C-terminal sequence of SLN tagged N-terminally with the FLAG epitope (NF-SLN) in endoplasmic reticulum (ER) retention was investigated by transfecting human embryonic kidney-293 cells with cDNAs encoding NF-SLN or a series of NF-SLN mutants in which C-terminal amino acids were deleted progressively. Immunofluorescence and immunoblotting of transfected cells by using anti-FLAG antibodies indicated that NF-SLN and PLN tagged at its N terminus with the FLAG epitope, even when overexpressed, were restricted to the ER. However, C-terminal truncation deletions of SLN, which lacked RSYQY, were not localized to ER and did not inhibit Ca(2+)-dependent Ca2+ uptake by SERCA. The shortest deletion constructs, NF-SLN 1-22 and NF-SLN 1-23, did not express stable protein products. However, all NF-SLN cDNA constructs, including NF-SLN 1-22 and NF-SLN 1-23, were expressed stably and localized to the ER when they were coexpressed with SERCA2a. These results show that NF-SLN subcellular distribution depends on SERCA coexpression and on its luminal, C-terminal RSYQY sequence. By using immunoprecipitation and MS, glucose-regulated protein 78/BiP and glucose-regulated protein 94 were identified as proteins that interact with NF-SLN through the RSYQY sequence. Thus, in the absence of SERCA, retention of NF-SLN in the ER is mediated through its association with other components through the C-terminal RSYQY sequence. Sarcolipin, a homologue of phospholamban, regulates Ca2+ uptake through the interaction with sarcoplasmic reticulum Ca2+ ATPase (SERCA) and is predomitly expressed in the atrial muscle. Although the atrial chamber-specific expression of sarcolipin could be primarily regulated at the transcriptional level, the transcriptional regulation remains poorly understood. Since mechanical stress plays an important role in transcriptional regulation of a gene involved in cardiac hypertrophy and remodeling, we generated left-sided or right-sided pressure-overload models by transverse aortic constriction (TAC) in ddY mice or by monocrotaline administration in Wistar rats, respectively. TAC significantly decreased the expression of sarcolipin, SERCA2a, and phospholamban mRNAs in the left atrium (LA) than those in the right atrium (RA). By contrast, monocrotaline administration significantly decreased the expression of sarcolipin, SERCA2a, and phospholamban mRNAs in the RA than those in the LA. The two independent complementary experiments unequivocally demonstrated that mechanical stress down-regulates the transcription of the sarcolipin gene. Sarcolipin (SLN) is an integral membrane protein that is expressed in both skeletal and cardiac muscle, where it inhibits SERCA (calcium ATPase) by lowering its apparent Ca2+ affinity in a manner similar to that of its homologue phospholamban (PLN). We use solution NMR to map the structural changes occurring within SLN upon interaction with the regulatory target, SERCA, co-reconstituting the two proteins in dodecylphosphocholine (DPC) detergent micelles, a system that preserves the native structure of SLN and the activity of SERCA, with the goal of comparing these interactions with those of the previously studied PLN-SERCA complex. Our analysis of the structural dynamics of SLN in DPC micelles shows this polypeptide to be partitioned into four subdomains: a short unstructured N terminus (residues 1-6), a short dynamic helix (residues 7-14), a more rigid helix (residues 15-26), and an unstructured C terminus (residues 27-31). Upon addition of SERCA, the different domains behave according to their dynamics, molding onto the surface of the enzyme. Remarkably, each domain of SLN behaves in a manner similar to that of the corresponding domains in PLN, supporting the hypothesis that both SLN and PLN bind SERCA in the same groove and with similar mechanisms. In animal models of conotruncal heart defects, an abnormal calcium sensitivity of the contractile apparatus and a depressed L-type calcium current have been described. Sarcoplasmic reticulum (SR) Ca(2+) ATPase (SERCA) is a membrane protein that catalyzes the ATP-dependent transport of Ca(2+) from the cytosol to the SR. The activity of SERCA is inhibited by phospholamban (PLN) and sarcolipin (SLN), and all these proteins participate in maintaining the normal intracellular calcium handling. Ryanodine receptors (RyRs) are the major SR calcium-release channels required for excitation-contraction coupling in skeletal and cardiac muscle. Our objective was to evaluate SERCA2a (i.e., the SERCA cardiac isoform), PLN, SLN, and RyR2 (i.e., the RyR isoform enriched in the heart) gene expression in myocardial tissue of patients affected by tetralogy of Fallot (TOF), a conotruncal heart defect. The gene expression of target genes was assessed semiquantitatively by RT-PCR using the calsequestrin (CASQ, a housekeeping gene) RNA as internal standard in the atrial myocardium of 23 pediatric patients undergoing surgical correction of TOF, in 10 age-matched patients with ventricular septal defect (VSD) and in 13 age-matched children with atrial septal defect (ASD). We observed a significantly lower expression of PLN and SLN in TOF patients, while there was no difference between the expression of SERCA2a and RyR2 in TOF and VSD. These data suggest a complex mechanism aimed to enhance the intracellular Ca(2+) reserve in children affected by tetralogy of Fallot. Sarcolipin is a novel regulator of cardiac sarcoplasmic reticulum Ca2+ ATPase 2a (SERCA2a) and is expressed abundantly in atria. In this study we investigated the physiological significance of sarcolipin in the heart by generating a mouse model deficient for sarcolipin. The sarcolipin-null mice do not show any developmental abnormalities or any cardiac pathology. The absence of sarcolipin does not modify the expression level of other Ca2+ handling proteins, in particular phospholamban, and its phosphorylation status. Calcium uptake studies revealed that, in the atria, ablation of sarcolipin resulted in an increase in the affinity of the SERCA pump for Ca2+ and the maximum velocity of Ca2+ uptake rates. An important finding is that ablation of sarcolipin resulted in an increase in atrial Ca2+ transient amplitudes, and this resulted in enhanced atrial contractility. Furthermore, atria from sarcolipin-null mice showed a blunted response to isoproterenol stimulation, implicating sarcolipin as a mediator of beta-adrenergic responses in atria. Our study documented that sarcolipin is a key regulator of SERCA2a in atria. Importantly, our data demonstrate the existence of distinct modulators for the SERCA pump in the atria and ventricles. Sarcolipin (SLN) inhibits sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) pumps. To evaluate the physiological significance of SLN in skeletal muscle, we compared muscle contractility and SERCA activity between Sln-null and wild-type mice. SLN protein expression in wild-type mice was abundant in soleus and red gastrocnemius (RG), low in extensor digitorum longus (EDL), and absent from white gastrocnemius (WG). SERCA activity rates were increased in soleus and RG, but not in EDL or WG, from Sln-null muscles, compared with wild type. No differences were seen between wild-type and Sln-null EDL muscles in force-frequency curves or maximum rates of force development (+dF/dt). Maximum relaxation rates (-dF/dt) of EDL were higher in Sln-null than wild type across a range of submaximal stimulation frequencies, but not during a twitch or peak tetanic contraction. For soleus, no differences were seen between wild type and Sln-null in peak tetanic force or +dF/dt; however, force-frequency curves showed that peak force during a twitch and 10-Hz contraction was lower in Sln-null. Changes in the soleus force-frequency curve corresponded with faster rates of force relaxation at nearly all stimulation frequencies in Sln-null compared with wild type. Repeated tetanic stimulation of soleus caused increased (-dF/dt) in wild type, but not in Sln-null. No compensatory responses were detected in analysis of other Ca(2+) regulatory proteins using Western blotting and immunohistochemistry or myosin heavy chain expression using immunofluorescence. These results show that 1) SLN regulates Ca(2+)-ATPase activity thereby regulating contractile kinetics in at least some skeletal muscles, 2) the functional significance of SLN is graded to the endogenous SLN expression level, and 3) SLN inhibitory effects on SERCA function are relieved in response to repeated contractions thus enhancing relaxation rates. Sarcolipin (SLN) is a key regulator of sarco(endo)plasmic reticulum (SR) Ca(2+)-ATPase (SERCA), and its expression is altered in diseased atrial myocardium. To determine the precise role of SLN in atrial Ca(2+) homeostasis, we developed a SLN knockout (sln-/-) mouse model and demonstrated that ablation of SLN enhances atrial SERCA pump activity. The present study is designed to determine the long-term effects of enhanced SERCA activity on atrial remodeling in the sln-/- mice. Calcium transient measurements show an increase in atrial SR Ca(2+) load and twitch Ca(2+) transients. Patch-clamping experiments demonstrate activation of the forward mode of sodium/calcium exchanger, increased L-type Ca(2+) channel activity, and prolongation of action potential duration at 90% repolarization in the atrial myocytes of sln-/- mice. Spontaneous Ca(2+) waves, delayed afterdepolarization, and triggered activities are frequent in the atrial myocytes of sln-/- mice. Furthermore, loss of SLN in atria is associated with increased interstitial fibrosis and altered expression of genes encoding collagen and other extracellular matrix proteins. Our results also show that the sln-/- mice are susceptible to atrial arrhythmias upon aging. Together, these findings indicate that ablation of SLN results in increased SERCA activity and SR Ca(2+) load, which, in turn, could cause abnormal intracellular Ca(2+) handling and atrial remodeling. Sarcolipin (SLN) is a 3 kD membrane protein found in sarcoplasmic reticulum (SR). It has 31 amino acid residues; SLN and phopholamban (PLB) are belong to the same protein family, so they have similar physiological functions. SLN inhibits sarcoplasmic reticulum Ca(2+) ATPase (SERCA) activity and reduces its affinity of Ca(2+), resulting in dysfunction of myocardial contraction and heart failure. However, much remains to be elucidated. SLN independently or in conjunction with PLB affects SERCA activity, imbalancing intracellular calcium homeostasis, and reducing myocardial contractivity; these effects promote the development of heart failure. The role of skeletal muscle in nonshivering thermogenesis (NST) is not well understood. Here we show that sarcolipin (Sln), a newly identified regulator of the sarco/endoplasmic reticulum Ca(2+)-ATPase (Serca) pump, is necessary for muscle-based thermogenesis. When challenged to acute cold (4 °C), Sln(-/-) mice were not able to maintain their core body temperature (37 °C) and developed hypothermia. Surgical ablation of brown adipose tissue and functional knockdown of Ucp1 allowed us to highlight the role of muscle in NST. Overexpression of Sln in the Sln-null background fully restored muscle-based thermogenesis, suggesting that Sln is the basis for Serca-mediated heat production. We show that ryanodine receptor 1 (Ryr1)-mediated Ca(2+) leak is an important mechanism for Serca-activated heat generation. Here we present data to suggest that Sln can continue to interact with Serca in the presence of Ca(2+), which can promote uncoupling of the Serca pump and cause futile cycling. We further show that loss of Sln predisposes mice to diet-induced obesity, which suggests that Sln-mediated NST is recruited during metabolic overload. These data collectively suggest that SLN is an important mediator of muscle thermogenesis and whole-body energy metabolism. Sarco(endo)plasmic reticulum Ca(2+)ATPase (SERCA) pump activity is modulated by phospholamban (PLB) and sarcolipin (SLN) in cardiac and skeletal muscle. Recent data suggest that SLN could play a role in muscle thermogenesis by promoting uncoupling of the SERCA pump (Lee, A.G. (2002) Curr. Opin. Struct. Biol. 12, 547-554 and Bal, N. C., Maurya, S. K., Sopariwala, D. H., Sahoo, S. K., Gupta, S. C., Shaikh, S. A., Pant, M., Rowland, L. A., Bombardier, E., Goonasekera, S. A., Tupling, A. R., Molkentin, J. D., and Periasamy, M. (2012) Nat. Med. 18, 1575-1579), but the mechanistic details are unknown. To better define how binding of SLN to SERCA promotes uncoupling of SERCA, we compared SLN and SERCA1 interaction with that of PLB in detail. The homo-bifunctional cross-linker (1,6-bismaleimidohexane) was employed to detect dynamic protein interaction during the SERCA cycle. Our studies reveal that SLN differs significantly from PLB: 1) SLN primarily affects the Vmax of SERCA-mediated Ca(2+) uptake but not the pump affinity for Ca(2+); 2) SLN can bind to SERCA in the presence of high Ca(2+), but PLB can only interact to the ATP-bound Ca(2+)-free E2 state; and 3) unlike PLB, SLN interacts with SERCA throughout the kinetic cycle and promotes uncoupling of the SERCA pump. Using SERCA transmembrane mutants, we additionally show that PLB and SLN can bind to the same groove but interact with a different set of residues on SERCA. These data collectively suggest that SLN is functionally distinct from PLB; its ability to interact with SERCA in the presence of Ca(2+) causes uncoupling of the SERCA pump and increased heat production. The sarco(endo)plasmic reticulum calcium ATPase (SERCA) is regulated in a tissue-dependent manner via interaction with the short integral membrane proteins phospholamban (PLN) and sarcolipin (SLN). Although defects in SERCA activity are known to cause heart failure, the regulatory mechanisms imposed by PLN and SLN could have clinical implications for both heart and skeletal muscle diseases. PLN and SLN have significant sequence homology in their transmembrane regions, suggesting a similar mode of binding to SERCA. However, unlike PLN, SLN has a conserved C-terminal luminal tail composed of five amino acids ((27)RSYQY), which may contribute to a distinct SERCA regulatory mechanism. We have functionally characterized alanine mutants of the C-terminal tail of SLN using co-reconstituted proteoliposomes of SERCA and SLN. We found that Arg(27) and Tyr(31) are essential for SLN function. We also tested the effect of a truncated variant of SLN (Arg(27)stop) and extended chimeras of PLN with the five luminal residues of SLN added to its C terminus. The Arg(27)stop form of SLN resulted in loss of function, whereas the PLN chimeras resulted in superinhibition with characteristics of both PLN and SLN. Based on our results, we propose that the C-terminal tail of SLN is a distinct, essential domain in the regulation of SERCA and that the functional properties of the SLN tail can be transferred to PLN.

What is the risk of developing acute myelogenous leukemia in Fanconi anemia?

A review of all of the cases of Fanconi anemia (FA) reported to the International Fanconi Anemia Registry (IFAR) indicates that at least 15% manifest acute myelogenous leukemia (AML) or preleukemia.

We analyzed data from 388 subjects with Fanconi anemia reported to the International Fanconi Anemia Registry (IFAR). Of those, 332 developed hematologic abnormalities at a median age of 7 years (range, birth to 31 years). Actuarial risk of developing hematopoietic abnormalities was 98% (95% confidence interval, 93% to 99%) by 40 years of age. Common hematologic abnormalities were thrombocytopenia and pancytopenia. These were often associated with decreased bone marrow (BM) cellularity (75% of cases studied). Clonal cytogenetic abnormalities developed in 23 of 68 persons with BM failure who had adequate studies. Actuarial risk of clonal cytogenetic abnormalities during BM failure was 67% (47% to 87%) by 30 years of age. Fifty-nine subjects developed myelodysplastic syndrome (MDS) or acute myelogenous leukemia (AML). Actuarial risk of MDS or AML was 52% (37% to 67%) by 40 years of age. Risk was higher in persons with than in those without a prior clonal cytogenetic abnormality (3% [0% to 9%] v 35% [0% to 79%]; P = .006). One hundred twenty persons died of hematologic causes including BM failure, MDS or AML and treatment related complications. Actuarial risk of death from hematologic causes was 81% (67% to 90%) by 40 years of age. Fanconi anemia (FA) is a genetically and phenotypically heterogeneous disorder defined by cellular hypersensitivity to DNA cross-linking agents; mutations in the gene defective in FA complementation group C, FAC, are responsible for the syndrome in a subset of patients. We have performed an analysis of the clinical effects of specific mutations in the FAC gene. Using the amplification refractory mutation system assays that we developed to rapidly detect FAC mutations, at least one mutated copy of the FAC gene was identified in 59 FA patients from the International Fanconi Anemia Registry (IFAR). This represents 15% of the 397 FA patients tested. FA-C patients were divided into three subgroups based on results of a genotype-phenotype analysis using the Cox proportional hazards model: (1) patients with the IVS4 mutation (n = 26); (2) patients with at least one exon 14 mutation (R548X or L554P) (n = 16); and (3) patients with at least one exon 1 mutation (322delG or Q13X) and no known exon 14 mutation (n = 17). Kaplan-Meier analysis shows that IVS4 or exon 14 mutations define poor risk subgroups, as they are associated with significantly earlier onset of hematologic abnormalities and poorer survival compared to exon 1 patients and to the non-FA-C IFAR population. There was no direct correlation between the degree of cellular hypersensitivity to the clastogenic effect of diepoxybutane and severity of clinical phenotype. Sixteen of the 59 FA-C patients (27%) have developed acute myelogenous leukemia. Thirteen of these patients have died; AML was the cause of death in 46% of the expired FA-C patients. This study enables us to define this clinically heterogeneous disorder genotypically to better predict clinical outcome and aid decision-making regarding major therapeutic modalities for a subset of FA patients.

How many different mutations have been associated with Muenke syndrome?

Muenke syndrome, also known as FGFR3-associated coronal synostosis, is defined molecularly by the presence of a heterozygous nucleotide transversion, c.749C>G, encoding the amino acid substitution Pro250Arg, in the fibroblast growth factor receptor type 3 gene (FGFR3).

Muenke syndrome, also known as FGFR3-associated coronal synostosis, is defined molecularly by the presence of a heterozygous nucleotide transversion, c.749C>G, encoding the amino acid substitution Pro250Arg, in the fibroblast growth factor receptor type 3 gene (FGFR3). This frequently occurs as a new mutation, manifesting one of the highest documented rates for any transversion in the human genome. To understand the biology of this mutation, we have investigated its parental origin, and the ages of the parents, in 19 families with de novo c.749C>G mutations. All ten informative cases originated from the paternal allele (95% confidence interval 74-100% paternal); the average paternal age at birth overall was 34.7 years. An exclusive paternal origin of mutations, and increased paternal age, were previously described for a different mutation (c.1138G>A) of the FGFR3 gene causing achondroplasia, as well as for mutations of the related FGFR2 gene causing Apert, Crouzon and Pfeiffer syndromes. We conclude that similar biological processes are likely to shape the occurrence of this c.749C>G mutation as for other mutations of FGFR3 as well as FGFR2. Mutations in the gene that encodes Fibroblast Growth Factor Receptor 3 (FGFR3) are associated with Achondroplasia (MIM 100800), Hypochondroplasia (MIM 146000), Muenke Syndrome (MIM 602849), Thanatophoric Dysplasia (MIM 187600, MIM 187601) and Lacrimo-Auriculo-Dento-Digital Syndrome (MIM 149730).Here we report a clinical and molecular study in a large cohort of 125 Portuguese patients with these skeletal disorders. The identification of the P250R mutation allowed the confirmation of the Muenke Syndrome in 9 out of the 52 cases referred. Two known mutations were found in the Thanatophoric Dysplasia referred cases. No mutations were identified in the LADD syndrome patient. In Achondroplasia and Hypochondroplasia, genetic heterogeneity was present amongst the 70 clinically diagnosed patients with 5 different mutations identified. As in other studies, complex phenotypic heterogeneity amongst patients carrying the same gene defect was observed. In several cases, the new amino acids encoded, as a consequence of mutations, were related to the severity of patients' phenotype. The presence of 10 misdiagnosed cases emphasizes the importance of performing mutation analysis of the hotspot regions responsible for both dysplasias (Ach and Hch). For patients with an unquestionable clinical diagnosis, lacking the most common mutations, a complete screening of FGFR3 is necessary. In about 30% of the patients with syndromal craniosynostosis, a genetic mutation can be traced. For the purpose of adequate genetic counseling and treatment of these patients, the full spectrum of clinical findings for each specific mutation needs to be appreciated. The Pro250Arg mutation in the FGFR3 gene is found in patients with Muenke syndrome and is one of the most frequently encountered mutations in craniosynostosis syndromes. A number of studies on the relationship between genotype and phenotype concerning this specific mutation have been published. Two Dutch families with Muenke syndrome were screened for the reported characteristics of this syndrome and for additional features. New phenotypical findings were hypoplasia of the frontal sinus, ptosis of the upper eyelids, dysplastic elbow joints with restricted elbow motion, and mild cutaneous syndactyly. Incidentally, polydactyly, severe ankylosis of the elbow, fusion of cervical vertebrae, and epilepsy were found. Upper eyelid ptosis is thought to be pathognomonic for Saethre-Chotzen syndrome but was also observed in our series of patients with Muenke syndrome. Because Muenke and Saethre-Chotzen syndrome can have similar phenotypes, DNA analysis is needed to distinguish between these syndromes, even when a syndrome diagnosis is already made in a family member. Craniosynostosis is the premature fusion of one or more sutures of the skull, which can be syndromic or isolated. Mutations in FGFR1, FGFR2, or FGFR3, among others, are often responsible for these syndromic cases. The associated of FGFR3 mutations with craniosynostosis has been restricted to three mutations, the common p.Pro250Arg in Muenke syndrome, p.Ala391Glu in Crouzon syndrome with acanthosis nigricans, and p.Pro250Leu identified in a family with isolated craniosynostosis. Other FGFR3 mutations result in various skeletal dysplasias: achondroplasia, hypochondroplasia, and thanatophoric dysplasia. Here, we report a novel mutation in exon 8 (IIIc) of FGFR3, p.Ala334Thr, in a young boy with mild craniosynostosis. The mutation segregated with mild craniosynostosis in the family and was absent in 188 normal controls. Alanine 334 is evolutionarily conserved in vertebrates and is located at the amino terminus of the βF loop in the FGFR3c isoform. The mutation is predicted to alter the protein tertiary structure which may impair its binding to its ligand, FGF1. The identification of a mutation in these clinically heterogeneous disorders can aid recurrence risk assessments. Although the implementation of a stepwise screening strategy is useful in diagnostics, mutations in unscreened regions of genes associated with craniosynostosis may explain a small proportion of craniosynostosis cases. Muenke syndrome is an autosomal domit craniosynostosis syndrome resulting from a defining point mutation in the Fibroblast Growth Factor Receptor3 (FGFR3) gene. Muenke syndrome is characterized by coronal craniosynostosis (bilateral more often than unilateral), hearing loss, developmental delay, and carpal and/or tarsal bone coalition. Tarsal coalition is a distinct feature of Muenke syndrome and has been reported since the initial description of the disorder in the 1990s. Although talocalcaneal coalition is the most common tarsal coalition in the general population, it has never previously been reported in a patient with Muenke syndrome. We present a 7-year-old female patient with Muenke syndrome and symptomatic talocalcaneal coalition. She presented at the age of 7 with limping, tenderness and pain in her right foot following a fall and strain of her right foot. She was treated with ibuprofen, shoe inserts, a CAM walker boot, and stretching exercises without much improvement in symptoms. A computed tomography (CT) scan revealed bilateral talocalcaneal coalitions involving the middle facet. She underwent resection of the talocalcaneal coalitions, remaining pain-free post-operatively with an improvement in her range of motion, gait, and mobility. This report expands the phenotype of tarsal coalition in Muenke syndrome to include talocalcaneal coalition. A literature review revealed a high incidence of tarsal coalition in all FGFR related craniosynostosis syndromes when compared to the general population, a difference that is statistically significant. The most common articulation involved in all syndromic craniosynostoses associated with FGFR mutations is the calcaneocuboid articulation.

How can the fetal Rhesus be determined with non-invasive testing?

The detection of fetal RhD status can be achieved with the non-invasive method of assessing free fetal DNA in the maternal blood.

OBJECTIVES: To develop a non-invasive method for determining fetal RhD status in order to provide improved care for women most at risk. DESIGN: A prospective study. METHODS: Fetal erythroblasts were enriched from the peripheral circulation of 96 RhD negative women with pregcies at various stages in gestation using discontinuous density gradients. Amplification of RhD-specific mRNAs was carried out by reverse transcription-polymerase chain reaction assay. RNA, rather than DNA, was selected for amplification because it rarely contaminates samples, thus resulting in fewer false positives; moreover, its presence in multiple copies per cell should enhance the sensitivity of the assay, resulting in fewer false negatives. The study was prospective, relying on postnatal serological confirmation of RhD phenotype. RESULTS: The assay was 75% accurate at predicting fetal RhD status, comparing favourably with standard genomic DNA-based assays. However, we found that accuracy dropped from 85% (29/34) in the third trimester of pregcy, to 82% (32/39) in the second and 48% (11/23) in the first trimester. Discordant data were due to false negatives in the majority (78%) of cases. CONCLUSIONS: We suggest that reverse transcription may be a useful and perhaps more sensitive alternative to standard genomic polymerase chain reaction in the majority of cases. However, under certain circumstances the absence or reduction of fetal erythroblasts or possibly RhD mRNA in some preparations may compromise the accuracy of the assay. PURPOSE: To examine the potential high throughput capability and efficiency of an automated DNA extraction system in combination with mass spectrometry for the non-invasive determination of the foetal Rhesus D status. METHODS: A total of 178 maternal plasma samples from RHD-negative pregt women were examined, from which DNA was extracted using the automated Roche MagNA Pure system. Presence of the foetal RHD gene was detected by PCR for RHD exon 7 and subsequent analysis using the Sequenom MassArray mass spectrometric system. RESULTS: We determined that as little as 15 pg of RHD-positive genomic DNA could be detected in a background of 585 pg of RHD-negative genomic DNA. The analysis of the clinical samples yielded a sensitivity and specificity of 96.1 and 96.1%, respectively. CONCLUSION: Our study indicated that automated DNA extraction in combination with mass spectrometry permits the determination of foetal Rhesus D genotype with an accuracy comparable to the current approaches using real-time PCR. BACKGROUND: Cell-free fetal nucleic acids (cffNA) can be detected in the maternal circulation during pregcy, potentially offering an excellent method for early non-invasive prenatal diagnosis (NIPD) of the genetic status of a fetus. Using molecular techniques, fetal DNA and RNA can be detected from 5 weeks gestation and are rapidly cleared from the circulation following birth. METHODS: We searched PubMed systematically using keywords free fetal DNA and NIPD. Reference lists from relevant papers were also searched to ensure comprehensive coverage of the area. RESULTS: Cell-free fetal DNA comprises only 3-6% of the total circulating cell-free DNA, therefore diagnoses are primarily limited to those caused by paternally inherited sequences as well as conditions that can be inferred by the unique gene expression patterns in the fetus and placenta. Broadly, the potential applications of this technology fall into two categories: first, high genetic risk families with inheritable monogenic diseases, including sex determination in cases at risk of X-linked diseases and detection of specific paternally inherited single gene disorders; and second, routine antenatal care offered to all pregt women, including prenatal screening/diagnosis for aneuploidy, particularly Down syndrome (DS), and diagnosis of Rhesus factor status in RhD negative women. Already sex determination and Rhesus factor diagnosis are nearing translation into clinical practice for high-risk individuals. CONCLUSIONS: The analysis of cffNA may allow NIPD for a variety of genetic conditions and may in future form part of national antenatal screening programmes for DS and other common genetic disorders. BACKGROUND: Hemolytic disease of the fetus and newborn (HDN) is caused primarily by feto-maternal RhD incompatibility. Although all RhD negative pregt women undergo routine antenatal RhD prophylaxis at 28 weeks of gestation, and following delivery if the newborn is RhD positive, HDN has not been eradicated. Here, we investigated fetal Rhesus D (RHD) genotype in maternal plasma during the first trimester of pregcy in our area. METHODS: Plasma samples were obtained from 111 RhD negative pregt women, between 9 and 13 weeks of gestation. DNA from maternal plasma containing cell-free fetal DNA (cffDNA) was analyzed by quantitative PCR (qPCR) to detect RHD exons 5 and 7. A beta-globin (HBB) sequence was quantified to estimate total DNA concentration. qPCR results were compared with newborn RhD determined in cord blood serum. The influence of several gestational parameters on DNA concentration was also analyzed. RESULTS: The specificity and sensitivity of the assay was 93% and 100%, respectively, with 97% diagnostic accuracy. Cell-free DNA concentrations during the first trimester of pregcy were not affected by the gestational parameters studied (free-beta fraction of human chorionic gonadotropin and pregcy-associated plasma protein A concentrations, fetal sex, materno-fetal ABO blood group incompatibility, maternal weight and gestational age). CONCLUSIONS: Non-invasive fetal RHD genotyping during the first trimester of pregcy can be determined with a high specificity, thus representing a valuable tool for improving the management of RhD negative pregt women. As a high percentage of pregt women participate in the routine first trimester combined screening program for aneuploidies, the fetal RHD study could be of immediate implementation, since the same blood collection could be used. BACKGROUND: Postnatal and antenatal anti-D prophylaxis have dramatically reduced maternal sensitisations and cases of rhesus disease in babies born to women with RhD negative blood group. Recent scientific advances mean that non-invasive prenatal diagnosis (NIPD), based on the presence of cell-free fetal DNA in maternal plasma, could be used to target prophylaxis on "at risk" pregcies where the fetus is RhD positive. This paper provides the first assessment of cost-effectiveness of NIPD-targeted prophylaxis compared to current policies. METHODS: We conducted an economic analysis of NIPD implementation in England and Wales. Two scenarios were considered. Scenario 1 assumed that NIPD will be only used to target antenatal prophylaxis with serology tests continuing to direct post-delivery prophylaxis. In Scenario 2, NIPD would also displace postnatal serology testing if an RhD negative fetus was identified. Costs were estimated from the provider's perspective for both scenarios together with a threshold royalty fee per test. Incremental costs were compared with clinical implications. RESULTS: The basic cost of an NIPD in-house test is £16.25 per sample (excluding royalty fee). The two-dose antenatal prophylaxis policy recommended by NICE is estimated to cost the NHS £3.37 million each year. The estimated threshold royalty fee is £2.18 and £8.83 for Scenarios 1 and 2 respectively. At a £2.00 royalty fee, mass NIPD testing would produce no saving for Scenario 1 and £507,154 per annum for Scenario 2. Incremental cost-effectiveness analysis indicates that, at a test sensitivity of 99.7% and this royalty fee, NIPD testing in Scenario 2 will generate one additional sensitisation for every £9,190 saved. If a single-dose prophylaxis policy were implemented nationally, as recently recommended by NICE, Scenario 2 savings would fall. CONCLUSIONS: Currently, NIPD testing to target anti-D prophylaxis is unlikely to be sufficiently cost-effective to warrant its large scale introduction in England and Wales. Only minor savings are calculated and, balanced against this, the predicted increase in maternal sensitisations may be unacceptably high. Reliability of NIPD assays still needs to be demonstrated rigorously in different ethnic minority populations. First trimester testing is unlikely to alter this picture significantly although other emerging technologies may. AIM: To design a protocol for non-invasive prenatal diagnosis of fetal Rhesus D (RhD) status. MATERIALS AND METHODS: A total of 112 single lymphocytes were used to test the efficiency of the assay. The protocol was validated using blood samples from 84 RhD-negative pregt women at 7-24 weeks of gestation. Cell-free DNA (cfDNA) was enzymatically digested using AciI and analyzed by a polymerase chain reaction (PCR) that allowed simultaneous amplification of RHD exons 7 and 10, SRY, RASFF1A and ACTB. RESULTS: On the one genome-equivalent level, the efficiency of the protocol was ≥ 94.6% for each locus amplified. Conclusive results from the first set of PCRs were obtained for 79 cases with one false-positive. In five cases the analysis was repeated and, subsequently, all cases were accurately diagnosed. CONCLUSION: The proposed protocol is rapid, applicable in most molecular diagnostic laboratories and provides the basis for non-invasive examination of fetal RhD with 96.7% specificity and 100% sensitivity. Alloimmunisation against the RhD red cell surface antigen was the most common cause of haemolytic disease of the fetus and newborn until recently. Maternal plasma has now almost replaced fetal cells obtained by amniocentesis or chorionic villous sampling, as the source of fetal DNA, hence eliminating the need for invasive sampling procedures. The fetal rhesus typing was done from maternal plasma in a woman in her fourth pregcy, though she was isoimmunised in her previous pregcies and needed invasive tests like cordocentesis in the past. The fetus was diagnosed to be rhesus negative from maternal plasma and that avoided the need for amniocentesis or cordocentesis. BACKGROUND: Analysis of cell free fetal (cff) DNA in maternal plasma is used routinely for non invasive prenatal diagnosis (NIPD) of fetal sex determination, fetal rhesus D status and some single gene disorders. True positive results rely on detection of the fetal target being analysed. No amplification of the target may be interpreted either as a true negative result or a false negative result due to the absence or very low levels of cffDNA. The hypermethylated RASSF1A promoter has been reported as a universal fetal marker to confirm the presence of cffDNA. Using methylation-sensitive restriction enzymes hypomethylated maternal sequences are digested leaving hypermethylated fetal sequences detectable. Complete digestion of maternal sequences is required to eliminate false positive results. METHODS: cfDNA was extracted from maternal plasma (n = 90) and digested with methylation-sensitive and insensitive restriction enzymes. Analysis of RASSF1A, SRY and DYS14 was performed by real-time PCR. RESULTS: Hypermethylated RASSF1A was amplified for 79 samples (88%) indicating the presence of cffDNA. SRY real time PCR results and fetal sex at delivery were 100% accurate. Eleven samples (12%) had no detectable hypermethylated RASSF1A and 10 of these (91%) had gestational ages less than 7 weeks 2 days. Six of these samples were male at delivery, five had inconclusive results for SRY analysis and one sample had no amplifiable SRY. CONCLUSION: Use of this assay for the detection of hypermethylated RASSF1A as a universal fetal marker has the potential to improve the diagnostic reliability of NIPD for fetal sex determination and single gene disorders. The collection of fetal genetic materials is required for the prenatal diagnosis of fetal genetic diseases. The conventional methods for sampling fetal genetic materials, such as amniocentesis and chorionic villus sampling, are invasive in nature and are associated with a risk of fetal miscarriage. For decades, scientists had been pursuing studies with goals to develop non-invasive methods for prenatal diagnosis. In 1997, the existence of fetal derived cell-free DNA molecules in plasma of pregt women was first demonstrated. This finding provided a new source of fetal genetic material that could be obtained safely through the collection of a maternal blood sample and provided a new avenue for the development of non-invasive prenatal diagnostic tests. Now 15 years later, the diagnostic potential of circulating fetal DNA analysis has been realized. Fruitful research efforts have resulted in the clinical implementation of a number of non-invasive prenatal tests based on maternal plasma DNA analysis and included tests for fetal sex assessment, fetal rhesus D blood group genotyping and fetal chromosomal aneuploidy detection. Most recently, research groups have succeeded in decoding the entire fetal genome from maternal plasma DNA analysis which paved the way for the achievement of non-invasive prenatal diagnosis of many single gene diseases. A paradigm shift in the practice of prenatal diagnosis has begun. BACKGROUND: Non-invasive prenatal testing of cell-free fetal DNA (cffDNA) in maternal plasma can predict the fetal RhD type in D negative pregt women. In Denmark, routine antenatal screening for the fetal RhD gene (RHD) directs the administration of antenatal anti-D prophylaxis only to women who carry an RhD positive fetus. Prophylaxis reduces the risk of immunization that may lead to hemolytic disease of the fetus and the newborn. The reliability of predicting the fetal RhD type depends on pre-analytical factors and assay sensitivity. We evaluated the testing setup in the Capital Region of Denmark, based on data from routine antenatal RHD screening. METHODS: Blood samples were drawn at gestational age 25 weeks. DNA extracted from 1 mL of plasma was analyzed for fetal RHD using a duplex method for exon 7/10. We investigated the effect of blood sample transportation time (n = 110) and ambient outdoor temperatures (n = 1539) on the levels of cffDNA and total DNA. We compared two different quantification methods, the delta Ct method and a universal standard curve. PCR pipetting was compared on two systems (n = 104). RESULTS: The cffDNA level was unaffected by blood sample transportation for up to 9 days and by ambient outdoor temperatures ranging from -10 °C to 28 °C during transport. The universal standard curve was applicable for cffDNA quantification. Identical levels of cffDNA were observed using the two automated PCR pipetting systems. We detected a mean of 100 fetal DNA copies/mL at a median gestational age of 25 weeks (range 10-39, n = 1317). CONCLUSION: The setup for real-time PCR-based, non-invasive prenatal testing of cffDNA in the Capital Region of Denmark is very robust. Our findings regarding the transportation of blood samples demonstrate the high stability of cffDNA. The applicability of a universal standard curve facilitates easy cffDNA quantification. In this study, we assessed the feasibility of fetal RhD genotyping by analysis of cell-free fetal DNA(cffDNA) extracted from plasma samples of Rhesus (Rh) D-negative pregt women by using real-time polymerase chain reaction (PCR). Fetal genotyping was performed on 30 RhD-negative women between 9 and 39 weeks of gestation who were referred to us for invasive testing [amniocentesis/chorionic villi sampling (CVS)]. The fetal RHD genotype was determined based on real-time PCR method. Exons 7 and 10 of the RHD and SRY genes were targeted. Among the pregt women, 12 were carrying male and 17 were carrying female fetuses. Out of 29 pregt women, 21 had RhD-positive and nine had RhD-negative fetuses. One sample (case 12, whose blood group was found to be AB Rh [+]) was excluded due to controversial results from repeated serological analyses. All prenatal results were in concordance with postnatal RhD status and fetal sex without false- positive or -negative results. Performing real-time PCR on cffDNA showed accurate, efficient and reliable results, allowing rapid and high throughput non invasive determination of fetal sex and RhD status in clinical samples. Non-invasive prenatal diagnosis and testing by analysis of cell-free DNA in the maternal circulation is a rapidly evolving field. Current clinical applications include fetal sex determination, fetal rhesus D determination, the diagnosis of some single gene disorders, and a highly accurate screening test for aneuploidies. In the future it is likely to be used for the diagnosis of an increasing range of monogenic disorders, and may even be used to profile entire fetal genomes. The introduction of these tests into clinical practice brings clear benefits but also poses several ethical, social and service delivery challenges. Here, we discuss the current clinical applications, discuss some of the technical and ethical challenges, and look to what the future might bring as technology continues to evolve. OBJECTIVE: Non-invasive fetal Rhesus (Rh) D genotyping, using cell-free fetal DNA (cffDNA) in the maternal blood, allows targeted antenatal anti-RhD prophylaxis in unsensitized RhD-negative pregt women. The purpose of this study was to determine the cost and benefit of this approach as compared to routine antenatal anti-RhD prophylaxis for all unsensitized RhD-negative pregt women, as is the current policy in the province of Alberta, Canada. METHODS: This study was a decision analysis based on a theoretical population representing the total number of pregcies in Alberta over a 1-year period (n = 69 286). A decision tree was created that outlined targeted prophylaxis for unsensitized RhD-negative pregt women screened for cffDNA (targeted group) vs routine prophylaxis for all unsensitized RhD-negative pregt women (routine group). Probabilities at each decision point and costs associated with each resource were calculated from local clinical and administrative data. Outcomes measured were cost, number of women sensitized and doses of Rh immunoglobulin (RhIG) administered. RESULTS: The estimated cost per pregcy for the routine group was 71.43 compared with 67.20 Canadian dollars in the targeted group. The sensitization rates per RhD-negative pregcy were equal, at 0.0012, for the current and targeted programs. Implementing targeted antenatal anti-RhD prophylaxis would save 4072 doses (20.1%) of RhIG over a 1-year period in Alberta when compared to the current program. CONCLUSIONS: These data support the feasibility of a targeted antenatal anti-RhD prophylaxis program, at a lower cost than that of the existing routine prophylaxis program, with no increased risk of sensitization. BACKGROUND: Discovery of short cell free fetal DNA (cffDNA) fragments in maternal plasma has created major changes in the field of prenatal diagnosis. The use of cffDNA to set up noninvasive prenatal test is limited due to the low concentration of fetal DNA in maternal plasma therefore, employing a high efficiency extraction method leads to more accurate results. The aim of this study was to evaluate the efficiency of Triton/Heat/Phenol (THP) protocol in comparison with the QIAamp DNA Blood mini Kit for cffDNA purification. METHODS: In order to evaluate the efficiency of THP protocol, DNA of Rhesus D (RhD) negative pregt women's plasma was collected, then real-time PCR for RHD exon 7 was performed. The Ct value data of real time PCR obtained by two different methods were compared and after delivery serology test on cord blood was done to validate the real time PCR results. RESULTS: The results indicated significant differences between two extraction methods (p=0.001). The mean±SD of Ct-value using THP protocol was 33.8±1.6 and 36.1±2.47 using QIAamp DNA Blood mini Kit. CONCLUSION: Our finding demonstrated that THP protocol was more effective than the QIAamp DNA Blood mini Kits for cffDNA extraction and lead to decrease the false negative results. OBJECTIVE: Anti-D immunoglobulin is applied to all pregt women having RhD incompatibility to prevent hemolytic disease of the newborn. The aim of this study is to determine fetal RhD status in the Rh incompatible pregcies with an non-invasive technique; free fetal DNA isolation from maternal circulation. In the case of Rh incompatibility especially with a history of previous fetal anemia, it can be beneficial to know Rh status antenatally in terms of monitoring fetuses with Rh positive [RhD(+)] status consciously. MATERIALS AND METHODS: Total free DNA was isolated in 50 Rh negative [RhD(-)] pregt women, who had RhD alloimmunisation with their husbands. The gene in isolated DNA was investigated with TagMan prob and real time PCR by using primers belonging to exon 7 of the RhD gene. RESULTS: The authors analyzed 50 RhD(-) women by using quantitative real time PCR technique. Five of them were RhD(-) and the rest of them were found to be RhD(+). After birth one of the infants who were analyzed as RhD(+) were found to be RhD(-). CONCLUSION: The detection of fetal RhD status by using a non-invasive method from maternal circulation was found to be possible. Assessing fetal RhD status non-invasively by using free fetal DNA in maternal blood will be cost-efficient, avoiding unnecessary indirect Coombs test and unnecessary Rhogam applications that is used in RH incompatible pregcies. This study will throw a fresh light on prenatal diagnosis. DNA sequencing technologies have advanced at an exponential rate in recent years: the first human genome was sequenced in 2001 after many years of effort by dozens of international laboratories at a cost of tens of millions of dollars, while in 2013 a genome can be sequenced within 24 hours for a few hundred dollars (exome sequencing takes only a few hours). More and more hospital laboratories are acquiring new high-throughput sequencing devices ("next-generation sequencers", NGS), allowing them to analyze tens or hundreds of genes, or even the entire exome. This is having a major impact on medical concepts and practices, especially with respect to genetics and oncology. This ability to search for mutations simultaneously in a large number of genes is finding applications in the diagnosis of Mendelian diseases (including at birth), routine screening for heterozygotes, and pre-conception diagnosis. NGS is now sufficiently sensitive to analyze circulating fetal DNA in maternal blood (cell-free fetal DNA, cffDNA), enabling applications such as non invasive diagnosis of fetal sex (and X-linked diseases), fetal rhesus among rhesus-negative women, trisomy and, in the near future, Mendelian mutations. Data on multifactorial diseases are still preliminary, but it should soon be possible to identify "strong" factors of genetic predisposition that have so far been beyond the scope of genome-wide association studies (GWAS). In the field of constitutional oncogenetics, NGS can also be used for simultaneous analysis of genes involved in " hereditary " cancers (21 breast cancer genes, 6 colon cancer genes, etc.). More generally, NGS can identify all genomic abnormalities (deletions, translocations, mutations) in a given maligt tissue (hemopathy or solid tumor), and has the potential to distinguish between important mutations (those that drive tumor progression) from " bystander " or accessory mutations, and also to identify "druggable" mutations amenable to targeted therapies (e.g. imatinib and Bcr/Abl rearrangement; verumafemib and the BRAF V600E mutation). Systematic sequencing of all the genes involved in drug metabolism and responsiveness will lead to individualized pharmacogenetics. Finally, sequencing of the tumoral and constitutional genomes, identfication of somatic mutations, and detection of pharmacogenetic variants will open up the era of personalized medicine. The first results of these targeted therapeutic indications show a gain in the duration of remission and survival, although the cost-effectiveness of these approaches remains to be determined. Finally, this huge capacity for genome sequencing raises a number of regulatory and ethical issues.

Which genes have been proposed as potential candidates for gene therapy of heart failure?

There are at least 6 genes which have been proposed as potential candidates of gene therapy in heart failure. 1. Cardiac Sarco-Endoplasmic Reticulum Calcium ATPase 2A (SERCA2A) 2. Inhibitor 1 (I-1) of Protein Phosphatase 1B 3. Protein Phosphatase 1B (PP1B) 4. Yes Associated Protein (YAP) 5. Survivin 6. S100A1

As a prerequisite for clinical application, we determined the long-term therapeutic effectiveness and safety of adeno-associated virus (AAV)-S100A1 gene therapy in a preclinical large animal model of heart failure. S100A1, a positive inotropic regulator of myocardial contractility, becomes depleted in failing cardiomyocytes in humans and animals, and myocardial-targeted S100A1 gene transfer rescues cardiac contractile function by restoring sarcoplasmic reticulum calcium (Ca(2+)) handling in acutely and chronically failing hearts in small animal models. We induced heart failure in domestic pigs by balloon occlusion of the left circumflex coronary artery, resulting in myocardial infarction. After 2 weeks, when the pigs displayed significant left ventricular contractile dysfunction, we administered, by retrograde coronary venous delivery, AAV serotype 9 (AAV9)-S100A1 to the left ventricular, non-infarcted myocardium. AAV9-luciferase and saline treatment served as control. At 14 weeks, both control groups showed significantly decreased myocardial S100A1 protein expression along with progressive deterioration of cardiac performance and left ventricular remodeling. AAV9-S100A1 treatment prevented and reversed these functional and structural changes by restoring cardiac S100A1 protein levels. S100A1 treatment normalized cardiomyocyte Ca(2+) cycling, sarcoplasmic reticulum calcium handling, and energy homeostasis. Transgene expression was restricted to cardiac tissue, and extracardiac organ function was uncompromised. This translational study shows the preclinical feasibility of long-term therapeutic effectiveness of and a favorable safety profile for cardiac AAV9-S100A1 gene therapy in a preclinical model of heart failure. Our results present a strong rationale for a clinical trial of S100A1 gene therapy for human heart failure that could potentially complement current strategies to treat end-stage heart failure. AIMS: Impaired myocardial sarcoplasmic reticulum calcium ATPase 2a (SERCA2a) activity is a hallmark of failing hearts, and SERCA2a gene therapy improves cardiac function in animals and patients with heart failure (HF). Deregulation of microRNAs has been demonstrated in HF pathophysiology. We studied the effects of therapeutic AAV9.SERCA2a gene therapy on cardiac miRNome expression and focused on regulation, expression, and function of miR-1 in reverse remodelled failing hearts. METHODS AND RESULTS: We studied a chronic post-myocardial infarction HF model treated with AAV9.SERCA2a gene therapy. Heart failure resulted in a strong deregulation of the cardiac miRNome. miR-1 expression was decreased in failing hearts, but normalized in reverse remodelled hearts after AAV9.SERCA2a gene delivery. Increased Akt activation in cultured cardiomyocytes led to phosphorylation of FoxO3A and subsequent exclusion from the nucleus, resulting in miR-1 gene silencing. In vitro SERCA2a expression also rescued miR-1 in failing cardiomyocytes, whereas SERCA2a inhibition reduced miR-1 levels. In vivo, Akt and FoxO3A were highly phosphorylated in failing hearts, but reversed to normal by AAV9.SERCA2a, leading to cardiac miR-1 restoration. Likewise, enhanced sodium-calcium exchanger 1 (NCX1) expression during HF was normalized by SERCA2a gene therapy. Validation experiments identified NCX1 as a novel functional miR-1 target. CONCLUSION: SERCA2a gene therapy of failing hearts restores miR-1 expression by an Akt/FoxO3A-dependent pathway, which is associated with normalized NCX1 expression and improved cardiac function. Use of gene therapy for heart failure is gaining momentum as a result of the recent successful completion of phase II of the Calcium Upregulation by Percutaneous Administration of Gene Therapy in Cardiac Disease (CUPID) trial, which showed clinical safety and efficacy of an adeno-associated viral vector expressing sarco-endoplasmic reticulum calcium ATPase (SERCA2a). Resorting to gene therapy allows the manipulation of molecular targets not presently amenable to pharmacologic modulation. This short review focuses on the molecular targets of heart failure gene therapy that have demonstrated translational potential. At present, most of these targets are related to calcium handling in the cardiomyocyte. They include SERCA2a, phospholamban, S100A1, ryanodine receptor, and the inhibitor of the protein phosphatase 1. Other targets related to cAMP signaling are reviewed, such as adenylyl cyclase. MicroRNAs are emerging as novel therapeutic targets and convenient vectors for gene therapy, particularly in heart disease. We propose a discussion of recent advances and controversies in key molecular targets of heart failure gene therapy. BACKGROUND: The targeting of Ca(2+) cycling has emerged as a potential therapy for the treatment of severe heart failure. These approaches include gene therapy directed at overexpressing sarcoplasmic reticulum (SR) Ca(2+) ATPase, or ablation of phospholamban (PLN) and associated protein phosphatase 1 (PP1) protein complexes. We previously reported that PP1β, one of the PP1 catalytic subunits, predomitly suppresses Ca(2+) uptake in the SR among the three PP1 isoforms, thereby contributing to Ca(2+) downregulation in failing hearts. In the present study, we investigated whether heart-failure-inducible PP1β-inhibition by adeno-associated viral-9 (AAV9) vector mediated gene therapy is beneficial for preventing disease progression in genetic cardiomyopathic mice. METHODS: We created an adeno-associated virus 9 (AAV9) vector encoding PP1β short-hairpin RNA (shRNA) or negative control (NC) shRNA. A heart failure inducible gene expression system was employed using the B-type natriuretic protein (BNP) promoter conjugated to emerald-green fluorescence protein (EmGFP) and the shRNA sequence. AAV9 vectors (AAV9-BNP-EmGFP-PP1βshRNA and AAV9-BNP-EmGFP-NCshRNA) were injected into the tail vein (2×10(11) GC/mouse) of muscle LIM protein deficient mice (MLPKO), followed by serial analysis of echocardiography, hemodynamic measurement, biochemical and histological analysis at 3 months. RESULTS: In the MLPKO mice, BNP promoter activity was shown to be increased by detecting both EmGFP expression and the induced reduction of PP1β by 25% in the myocardium. Inducible PP1βshRNA delivery preferentially ameliorated left ventricular diastolic function and mitigated adverse ventricular remodeling. PLN phosphorylation was significantly augmented in the AAV9-BNP-EmGFP-PP1βshRNA injected hearts compared with the AAV9-BNP-EmGFP-NCshRNA group. Furthermore, BNP production was reduced, and cardiac interstitial fibrosis was abrogated at 3 months. CONCLUSION: Heart failure-inducible molecular targeting of PP1β has potential as a novel therapeutic strategy for heart failure. Advances in understanding the molecular basis of myocardial dysfunction, together with the evolution of increasingly efficient gene transfer technology, make gene-based therapy a promising treatment option for heart conditions. Cardiovascular gene therapy has benefitted from recent advancements in vector technology, design, and delivery modalities. There is a critical need to explore new therapeutic approaches in heart failure, and gene therapy has emerged as a viable alternative. Advances in understanding of the molecular basis of myocardial dysfunction, together with the development of increasingly efficient gene transfer technology, has placed heart failure within reach of gene-based therapy. The recent successful and safe completion of a phase 2 trial targeting the cardiac sarcoplasmic/endoplasmic reticulum Ca2+ ATPase pump (SERCA2a) has the potential to open a new era for gene therapy for heart failure. AIMS: The aim of this study was to investigate anti-apoptotic gene therapy using ultrasound-mediated plasmid delivery of survivin, an inhibitor of apoptosis protein, to prevent apoptosis and to attenuate left ventricular (LV) systolic dysfunction in a model of heart failure induced by doxorubicin. METHODS AND RESULTS: Effect of survivin transduction was investigated in vitro in rat cardiomyoblasts. After survivin transduction, survivin protein was detected in cell culture supernate confirming secretion of extracellular survivin. Under doxorubicin stimulation, survivin-transduced cells had significantly reduced apoptosis; however, incubation with survivin-conditioned media also showed reduced apoptosis that was absent with null-conditioned media. Doxorubicin-induced cardiomyopathy was established in Fischer rats. Subsets of animals underwent ultrasound-mediated survivin gene delivery or empty vector gene delivery at Week 3. Control rats received doxorubicin alone. Animals were studied using PCR, immunohistochemistry, echocardiography, and invasive haemodynamic studies out to Week 6. By Week 6, LV % fractional shortening by echocardiography and systolic function by pressure-volume loops were greater in survivin treated when compared with control- and empty-treated animals. There was reduced apoptosis by TUNEL and caspase activity in survivin-treated animals compared with control and empty treated at Week 4, with reduced interstitial fibrosis at Week 6. CONCLUSION: Survivin gene therapy can attenuate the progression of LV systolic dysfunction in doxorubicin cardiomyopathy. This effect can be attributed to decreased myocyte apoptosis and prevention of maladaptive LV remodelling, by both direct myocyte transfection and potentially by paracrine mechanisms. RATIONALE: Yes-associated protein (YAP), the terminal effector of the Hippo signaling pathway, is crucial for regulating embryonic cardiomyocyte proliferation. OBJECTIVE: We hypothesized that YAP activation after myocardial infarction (MI) would preserve cardiac function and improve survival. METHODS AND RESULTS: We used a cardiac-specific, inducible expression system to activate YAP in adult mouse heart. Activation of YAP in adult heart promoted cardiomyocyte proliferation and did not deleteriously affect heart function. Furthermore, YAP activation after MI preserved heart function and reduced infarct size. Using adeno-associated virus subtype 9 (AAV9) as a delivery vector, we expressed human YAP (hYAP) in the adult murine myocardium immediately after MI. We found that AAV9:hYAP significantly improved cardiac function and mouse survival. AAV9:hYAP did not exert its salutary effects by reducing cardiomyocyte apoptosis. Rather, AAV9:hYAP stimulated adult cardiomyocyte proliferation. Gene expression profiling indicated that AAV9:hYAP stimulated expression of cell cycle genes and promoted a less mature cardiac gene expression signature. CONCLUSIONS: Cardiac-specific YAP activation after MI mitigated myocardial injury, improved cardiac function, and enhanced survival. These findings suggest that therapeutic activation of YAP or its downstream targets, potentially through AAV-mediated gene therapy, may be a strategy to improve outcome after MI. The treatment of heart failure (HF) may be entering a new era with clinical trials currently assessing the value of gene therapy as a novel therapeutic strategy. If these trials demonstrate efficacy then a new avenue of potential treatments could become available to the clinicians treating HF. In principle, gene therapy allows us to directly target the underlying molecular abnormalities seen in the failing myocyte. In this review we discuss the fundamentals of gene therapy and the challenges of delivering it to patients with HF. The molecular abnormalities underlying HF are discussed along with potential targets for gene therapy, focusing on SERCA2a. We discuss the laboratory and early clinical evidence for the benefit of SERCA2a gene therapy in HF. Finally, we discuss the ongoing clinical trials of SERCA2a gene therapy and possible future directions for this treatment.

DX-88 is investigational name of which drug?

DX-88 is investigational name of a drug Ecallantide, a 60-amino acid recombinant protein discovered through phage display technology, that is a highly specific, potent inhibitor of human plasma kallikrein that has been used successfully in the treatment of patients experiencing acute hereditary angioedema attacks.

Deficiency of C1 Inhibitor leads to unopposed activation of complement, with localized, unpredictable, and sometimes life-threatening attacks of angioedema. Treatment with plasma-derived C1 Inhibitor rapidly aborts attacks, and may be lifesaving, but is expensive, requires use of a pooled blood product, may need to be repeated and may not be effective in autoantibody mediated angioedema. The antifibrinolytic agents aprotinin, tranexamic acid, and epsilon-aminocaproic acid are useful for prophylaxis and treatment of angioedema, likely by inhibiting plasmin. Specific drugs to replace the deficient C1 Inh have not been reported. The kallikrein inhibitor DX-88 (Dyax) has received orphan drug status in Europe and is undergoing clinical trial in Europe and the USA. Hereditary angioedema (HAE) manifests as intermittent, painful attacks of submucosal oedema affecting the larynx, gastrointestinal tract or limbs. Currently, acute treatment is available in Europe but not USA, and requires intravenous administration of a pooled blood product. HAE is most likely caused by dysinhibition of the contact cascade, resulting in overproduction of bradykinin. DX-88 (ecallantide, Dyax Corp.) is a highly specific recombit plasma kallikrein inhibitor that halts the production of bradykinin and can be dosed subcutaneously. In a placebo-controlled Phase II trial in patients with HAE, DX-88 resulted in significant improvement in symptoms compared with placebo. A Phase III trial is ongoing. This review explains the pathophysiology of HAE and the mechanism by which DX-88, a non-intravenous, nonplasma-derived therapy, might improve the disease, and discusses the clinical course of HAE and available treatments. Finally, it explores the potential value and efficacy of DX-88 in treating HAE. OBJECTIVE: To provide an overview on the current status of emerging therapies for hereditary angioedema (HAE) in the United States. DATA SOURCES: Summary statements were obtained from each pharmaceutical company regarding their agent. STUDY SELECTION: Each agent is undergoing or has completed phase 3, double-blind, placebo-controlled trials. RESULTS: Berinert P, a purified, virus-inactivated, human plasma-derived C1 inhibitor (C1-INH) concentrate, is being investigated in 2 international, multicenter, prospective trials. Experience with this agent in Europe and Canada indicates it is effective and safe. Cinryze is a ofiltered C1-INH replacement therapy demonstrated to be effective and safe in acute and prophylactic arms of a phase 3, double-blind, placebo-controlled study. Rhucin, a recombit human C1-INH replacement therapy from transgenic rabbits, has been shown to be effective and safe in phase 2 and phase 2/3 studies, with an additional phase 3 study ongoing. DX-88 or ecallantide, a potent and specific inhibitor of plasma kallikrein, achieved all primary and secondary efficacy end points in a placebo-controlled, double-blind, phase 3 study, with a second phase 3 study ongoing. Icatibant, a potent and specific peptidomimetic bradykinin 2 receptor antagonist, was studied in 2 phase 3 trials: FAST 1 (For Angioedema Subcutaneous Treatment) did not achieve statistical significance for the primary end point but did so for secondary end points, whereas FAST 2 achieved statistical significance for primary and secondary end points. CONCLUSIONS: The future treatment of HAE in the United States appears promising based on progress being made in drug development for this orphan disease. BACKGROUND: Plasma kallikrein plays a major role in the contact (kallikrein-kinin) cascade producing bradykinin. Bradykinin is a vasodilator, which increases vascular permeability, activates inflammation and produces pain. Plasma kallikrein is also crosslinked to the coagulation system and the complement cascade. OBJECTIVE: Ecallantide (DX-88) is a potent and specific inhibitor of plasma kallikrein. Ecallantide is a recombitly produced and engineered small protein based on the first Kunitz domain of human tissue factor pathway inhibitor. It was identified through phage display technology. METHODS: The search terms 'ecallantide', 'DX-88' and 'hereditary angioedema' were entered into Pubmed/Medline, ClinicalTrials and Google. RESULTS/CONCLUSION: At present, the drug is being studied for two major indications. First, the results for the treatment of hereditary angioedema are promising. Second, a prospective randomised multi-centre trial for the reduction of blood loss during on-pump cardiothoracic surgery will be terminated in October 2008. Hereditary angioedema (HAE) is a rare disorder characterized by recurrent attacks of swelling that may involve multiple anatomical locations. In the majority of patients, it is caused by a functional or quantitative defect in the C1 inhibitor (C1-INH), which is an important regulator of the complement, fibrinolytic, kallikrein-kinin and coagulation systems. Standard treatments used for other types of angioedema are ineffective for HAE. Traditional therapies for HAE, including fresh frozen plasma, epsilon-aminocaproic acid and danazol, may be well tolerated and effective in some patients; however, there are limitations both in their safety and efficacy. Several novel therapies have completed phase III trials in the US, including: (i) plasma-derived C1-INH replacement therapies (Berinert P and Cinryze); (ii) a recombit C1-INH replacement therapy (conestat alfa; Rhucin); (iii) a kallikrein inhibitor (ecallantide [DX-88]); and (iv) a bradykinin-2-receptor antagonist (icatibant). Both Berinert P and Cinryze are reported to have excellent efficacy and safety data from phase III trials. Currently, only Cinryze has been approved for prophylactic use in the US. US FDA approval for other novel agents to treat HAE and for the use of Cinryze in the treatment of acute attacks is pending. Hereditary angioedema (HAE) resulting from the deficiency of the C1 inhibitor protein is a rare disease, characterized by paroxysms of edema formation in the subcutis and in the submucosa. Edema can cause obstruction of the upper airway, which may lead to suffocation. Prompt elimination of edema is necessary to save patients from this life-threatening condition. Essentially, these edematous attacks are related to the activation of the kinin-kallikrein system and the consequent release of bradykinin. Ecallantide (known as DX-88 previously), a potent and specific inhibitor of plasma kallikrein is an innovative medicinal product. This is the only agent approved recently by the FDA for all localizations of edematous HAE attacks. Its advantages include no risk of viral contamination, high selectivity, very rapid onset of action, good tolerability, and straightforward subcutaneous administration. Owing to the risk of anaphylaxis, ecallantide should be administered by a health care professional. A postmarketing survey to improve risk-assessment and risk-minimization has been launched. The results of these studies may lead to the approval of ecallantide for self-administration.

What type of arrhythmia is known as bidirectional ventricular tachycardia (BDVT)?

Bidirectional ventricular tachycardia (BVT), which is characterized by an alternating beat-to-beat ECG QRS axis, is a rare but intriguing arrhythmia associated with digitalis toxicity, familial catecholaminergic polymorphic ventricular tachycardia (CPVT), and several other conditions that predispose cardiac myocytes to delayed afterdepolarizations (DADs) and triggered activity. Bidirectional ventricular tachycardia (BVT) is an uncommon type of polymorphic ventricular tachycardia (PVT). Based on similarity of electrocardiographic features, bidirectional ventricular tachycardia has been considered a variant of long QT syndrome. Evidence from human and animal studies attributes BVT to alternating ectopic foci originating from the distal His-Purkinje system in the left and/or right ventricle, respectively. This "ping pong" mechanism of reciprocating bigeminy readily produces the characteristic ECG pattern of BVT and its degeneration to polymorphic VT if additional sites develop bigeminy.

Electrocardiograms taken from 11 patients in sinus rhythm with ventricular ectopic rhythms from two different foci were analyzed to find the number of sinus beats, S, between the ectopic rhythms (S values). Three out of 11 patients had the S values typical for concealed ectopic rhythms. One of them had concealed bigeminy of 2n-1 form that occasionally shifted to 2n form. Following the shift, S values of 2n-1 form were always achieved by the occurrence of double ventricular ectopic rhythms in succession. Concealed trigeminy of 3n and 3n-2 form was seen in the other two patients. Double ventricular ectopic rhythms had bizarre abnormal QRS complexes of two different morphologies and were inscribed in opposite directions. Ectopic rhythms in each case had parasystolic characteristics. These observations suggest bifocal automaticity as a mechanism for bidirectional ventricular tachycardia. Bidirectional ventricular tachycardia, defined as the rapid alternation of the QRS complexes with successive opposing axial deviation, is a rare arrhythmia. In the rare cases which have undergone endocavitary investigations, an infrahisian origin has generally been proved. However, the mechanism of these tachycardias remains poorly understood and is discussed with respect to a new case. Bidirectional tachycardia occurred in a 79 year old woman with previous diaphragmatic and anterior wall infarction. It was a wide QRS tachycardia at 180/min with a succession of ventriculogrammes of opposing axis in the frontal plane and permanent right bundle branch block over the right precordium. The two types of tachycardia were observed, monomorphic type A or Type B or a combination of the two realising an A-B bidirectional tachycardia. The origin of these episodes, which occurred on a background of atrial tachycardia at about 100/min, was ventricular as shown by the absence of a His potential before the ventricular complexes in tachycardia. The presence of ventricular extrasystoles with relatively fixed coupling intervals, and the results of endocavitary investigation were suggestive of a reentry phenomenon ventricular extrastimuli were capable of transforming the bidirectional into monomorphic tachycardia and vice versa; this suggests that A was at times the origin of a reentry B, but protected by A, tachycardia B could be sustained. In the light of previously reported cases with documented endocavitary investigation and this new case, it seems possible to talk in terms of true "bidirectional ventricular tachycardia", a tachycardia whose mechanism is obscure but certainly not univocal. Based on similarity of electrocardiographic features, bidirectional ventricular tachycardia has been considered a variant of long QT syndrome. Genes causing long QT syndrome were used as candidate genes in 4 patients with bidirectional ventricular tachycardia. In 2 patients, we identified a common low penetrance HERG allele (R1047L) with an intermediate biophysical phenotype. A 84-year-old man presented to the emergency department complaining of chest pain and palpitations. He had no history of coronary artery disease. The 12-lead electrocardiography showed bidirectional ventricular tachycardia (BVT). Coronary angiography revealed severe mid left anterior descending and mid left circumflex lesions. The BVT, in this case, was most likely due to myocardial ischema. The ethiology of published BVT cases are most commonly digitalis toxicity and rarely herbal aconitine poisoning, hypokalemic periodic paralysis, cathecolaminergic VT, myocarditis, and Anderson-Tawil syndrome. The patient had neither of these underlying conditions. To the best of our knowledge and research in the literature, there was no report of bidirectional VT in the patients with myocardial infarction. BACKGROUND: Bidirectional ventricular tachycardia (BVT), which is characterized by an alternating beat-to-beat ECG QRS axis, is a rare but intriguing arrhythmia associated with digitalis toxicity, familial catecholaminergic polymorphic ventricular tachycardia (CPVT), and several other conditions that predispose cardiac myocytes to delayed afterdepolarizations (DADs) and triggered activity. Evidence from human and animal studies attributes BVT to alternating ectopic foci originating from the distal His-Purkinje system in the left and/or right ventricle, respectively. OBJECTIVE: The purpose of this study was to evaluate a simple "ping pong" model of reciprocating bigeminy to explain BVT. METHODS: We constructed a two-dimensional anatomic model of the rabbit ventricles with a simplified His-Purkinje system, in which different sites in the His-Purkinje system had different heart rate thresholds for DAD-induced bigeminy. RESULTS: When the heart rate exceeded the threshold for bigeminy at the first site in the His-Purkinje system, ventricular bigeminy developed, causing the heart rate to accelerate and exceed the threshold for bigeminy at the second site. Thus, the triggered beat from the first site induced a triggered beat from the second site. The triggered beat from the second site next reciprocated by inducing a triggered beat from the first site, and so forth. Bigeminy from two sites produced BVT, and that from three or more sites produced polymorphic VT. CONCLUSION: This "ping pong" mechanism of reciprocating bigeminy readily produces the characteristic ECG pattern of BVT and its degeneration to polymorphic VT if additional sites develop bigeminy. Bidirectional ventricular tachycardia (BVT) is an uncommon type of polymorphic ventricular tachycardia (PVT) with alternating polarity of the QRS complex most commonly described digitalis toxicity. Recent data has demonstrated the possible molecular basis of this electrocardiographic phenomenon. To our knowledge this is the first reported case of BVT in a patient with orthotopic cardiac transplantation and coronary allograft vasculopathy.

Which genes have been found to be associated with restless leg syndrome

Human L-Ferritin The genotypes of five specific single-nucleotide polymorphisms (SNPs) in three genes Homozygosity for the T-allele of BTBD9 rs9296249 MEIS1 Intragenic guanosine triphosphate cyclohydrolase-1 duplication LRRK2 gene mutation

BACKGROUND: Restless legs syndrome (RLS) is a common sensory-motor disorder characterized by paresthesias and an intense urge to move the legs with a considerable familial aggregation. To date, no gene mutation has been found, but five gene loci have been mapped in primary RLS to chromosomes 12q, 14q, 9p, 2q, and 20p (RLS1 through 5). PATIENTS/METHODS: We identified a four-generational German RLS family with 37 family members including 15 affected cases. We performed linkage analysis using microsatellite markers at the five known loci. Prompted by the identification of a potentially shared haplotype near the RLS3 locus, we expanded the investigated linkage region on chromosome 9p using additional DNA markers. RESULTS: Mode of inheritance in our RLS family was compatible with an autosomal domit pattern, and disease onset was mainly in childhood or adolescence. We excluded linkage to the RLS1, RLS2, RLS4, and RLS5 loci. However, we identified a likely new RLS gene locus (RLS3*) on chromosome 9p with a maximum lod score of 3.60 generated by model-based multipoint linkage analysis. A haplotype flanked by D9S974 and D9S1118 in a 9.9-Mb region, centromeric to RLS3, was shared by all 12 investigated patients. In addition, 11 of them carried a common haplotype extending telomeric to D9S2189 that is located within RLS3. CONCLUSIONS: We demonstrate linkage to a locus on chromosome 9p that is probably distinct from RLS3. Our family with a rather homogeneous phenotype and very early disease onset represents a unique opportunity to further elucidate the genetic causes of the frequent restless leg syndrome. BACKGROUND: Autosomal domit dopa-responsive dystonia is commonly caused by mutations in the guanosine triphosphate cyclohydrolase-1 gene. METHODS: We report a British family that has been followed for more than 20 years in which no mutations were previously identified. RESULTS: Reanalysis of this pedigree detected a duplication of guanosine triphosphate cyclohydrolase-1 exon 2 in affected family members. mRNA analysis showed a mutant transcript with a tandem exon 2 duplication. Four family members developed dopa-responsive dystonia, with onset in their late teens, and subsequently developed restless leg syndrome and migraine. CONCLUSIONS: This is the first report of an intragenic guanosine triphosphate cyclohydrolase-1 duplication in a dopa-responsive dystonia family. BACKGROUND: Restless legs syndrome (RLS) is a sleep related movement disorder that occurs both in an idiopathic form and in symptomatic varieties. RLS is a frequent and distressing comorbidity in end stage renal disease (ESRD). For idiopathic RLS (iRLS), genetic risk factors have been identified, but their role in RLS in ESRD has not been investigated yet. Therefore, a case-control association study of these variants in ESRD patients was performed. METHODS: The study genotyped 10 iRLS associated variants at four loci encompassing the genes MEIS1, BTBD9, MAP2K5/SKOR1, and PTPRD, in two independent case-control samples from Germany and Greece using multiplex PCR and MALDI-TOF (matrix assisted laser desorption/ionisation time-of-flight) mass spectrometry. Statistical analysis was performed as logistic regression with age and gender as covariates. For the combined analysis a Cochran-Mantel-Haenszel test was applied. RESULTS: The study included 200 RLS-positive and 443 RLS-negative ESRD patients in the German sample, and 141 and 393 patients, respectively, in the Greek sample. In the German sample, variants in MEIS1 and BTBD9 were associated with RLS in ESRD (P(nom)≤0.004, ORs 1.52 and 1.55), whereas, in the Greek sample, there was a trend for association to MAP2K5/SKOR1 and BTBD9 (P(nom)≤0.08, ORs 1.41 and 1.33). In the combined analysis including all samples, BTBD9 was associated after correction for multiple testing (P(corrected)=0.0013, OR 1.47). CONCLUSIONS: This is the first demonstration of a genetic influence on RLS in ESRD patients with BTBD9 being significantly associated. The extent of the genetic predisposition could vary between different subgroups of RLS in ESRD. BACKGROUND: Iron deficiency is a frequent side effect of blood donation. In recent years, several studies have described genetic variants associated with iron concentrations. However, the impact of these variants on iron levels is unknown in blood donors. Knowledge of genetic variants that predispose donors to iron deficiency would allow bleeding frequency and iron supplementation to be tailored to the individual donor. STUDY DESIGN AND METHODS: The genotypes of five specific single-nucleotide polymorphisms (SNPs) in three genes that have been previously associated with iron status and/or restless leg syndrome (RLS) were investigated in two groups of female blood donors. The first group had low iron stores (serum ferritin ≤ 12 µg/L, n = 657), and the second group had normal to high iron stores (serum ferritin > 30 µg/L, n = 645). Genotype distribution for each of the SNPs was compared between the two groups. RESULTS: Homozygosity for the T-allele of BTBD9 rs9296249 was associated with lower serum ferritin. The odds ratio for low serum ferritin was 1.35 (95% confidence interval, 1.02-1.77; p = 0.03) when comparing donors with the TT genotype with donors with the CT genotype. CONCLUSION: A frequent polymorphism in BTBD9 was significantly associated with serum ferritin. This polymorphism has previously been associated with RLS, but not low iron stores in blood donors. LRRK2 gene mutations (PARK8) are a common cause of genetic Parkinson disease (PD). G2019S, the most frequent mutation, is responsible for both familial and sporadic cases of PD. The clinical picture is usually indistinguishable from that observed in idiopathic PD; however, a wide range of clinical presentations and pathological findings has been described. Restless leg syndrome (RLS) is a disabling sleep-related sensorimotor disorder whose pathogenesis is likely related to dopaminergic dysfunction. We report a 77-year-old woman with RLS and familial history of parkinsonism. The father, one sister, two cousins and one uncle were affected by PD. The proband and her sister were analyzed for mutations in LRRK2 gene and resulted to carry one heterozygous G2019S mutation in LRRK2 gene. The association between RLS and LRRK2 gene mutation may be casual, but it can hypothesized that RLS is a possible phenotypic presentation in PARK8. The ubiquitously expressed iron storage protein ferritin plays a central role in maintaining cellular iron homeostasis. Cytosolic ferritins are composed of heavy (H) and light (L) subunits that co-assemble into a hollow spherical shell with an internal cavity where iron is stored. The ferroxidase activity of the ferritin H chain is critical to store iron in its Fe3+ oxidation state, while the L chain shows iron nucleation properties. We describe a unique case of a 23-yr-old female patient affected by a homozygous loss of function mutation in the L-ferritin gene, idiopathic generalized seizures, and atypical restless leg syndrome (RLS). We show that L chain ferritin is undetectable in primary fibroblasts from the patient, and thus ferritin consists only of H chains. Increased iron incorporation into the FtH homopolymer leads to reduced cellular iron availability, diminished levels of cytosolic catalase, SOD1 protein levels, enhanced ROS production and higher levels of oxidized proteins. Importantly, key phenotypic features observed in fibroblasts are also mirrored in reprogrammed neurons from the patient's fibroblasts. Our results demonstrate for the first time the pathophysiological consequences of L-ferritin deficiency in a human and help to define the concept for a new disease entity hallmarked by idiopathic generalized seizure and atypical RLS.

Is the circadian clock involved in ribosome biogenesis?

Yes. The circadian clock coordinates ribosome biogenesis. It influences the temporal translation of a subset of mRNAs involved in ribosome biogenesis by controlling the transcription of translation initiation factors as well as the clock-dependent rhythmic activation of signaling pathways involved in their regulation.

Can mutations in Calmodulin cause ventricular fibrillation?

Yes, mutations in CALM underly IVF manifesting in childhood and adolescence.

Sodium channels are principal molecular determits responsible for myocardial conduction and maintece of the cardiac rhythm. Calcium ions (Ca2+) have a fundamental role in the coupling of cardiac myocyte excitation and contraction, yet mechanisms whereby intracellular Ca2+ may directly modulate Na channel function have yet to be identified. Here we show that calmodulin (CaM), a ubiquitous Ca2+-sensing protein, binds to the carboxy-terminal 'IQ' domain of the human cardiac Na channel (hH1) in a Ca2+-dependent manner. This binding interaction significantly enhances slow inactivation-a channel-gating process linked to life-threatening idiopathic ventricular arrhythmias. Mutations targeted to the IQ domain disrupted CaM binding and eliminated Ca2+/CaM-dependent slow inactivation, whereas the gating effects of Ca2+/CaM were restored by intracellular application of a peptide modelled after the IQ domain. A naturally occurring mutation (A1924T) in the IQ domain altered hH1 function in a manner characteristic of the Brugada arrhythmia syndrome, but at the same time inhibited slow inactivation induced by Ca2+/CaM, yielding a clinically benign (arrhythmia free) phenotype. OBJECTIVES: This study aimed to identify the genetic defect in a family with idiopathic ventricular fibrillation (IVF) manifesting in childhood and adolescence. BACKGROUND: Although sudden cardiac death in the young is rare, it frequently presents as the first clinical manifestation of an underlying inherited arrhythmia syndrome. Gene discovery for IVF is important as it enables the identification of individuals at risk, because except for arrhythmia, IVF does not manifest with identifiable clinical abnormalities. METHODS: Exome sequencing was carried out on 2 family members who were both successfully resuscitated from a cardiac arrest. RESULTS: We characterized a family presenting with a history of ventricular fibrillation (VF) and sudden death without electrocardiographic or echocardiographic abnormalities at rest. Two siblings died suddenly at the ages of 9 and 10 years, and another 2 were resuscitated from out-of-hospital cardiac arrest with documented VF at ages 10 and 16 years, respectively. Exome sequencing identified a missense mutation affecting a highly conserved residue (p.F90L) in the CALM1 gene encoding calmodulin. This mutation was also carried by 1 of the siblings who died suddenly, from whom DNA was available. The mutation was present in the mother and in another sibling, both asymptomatic but displaying a marginally prolonged QT interval during exercise. CONCLUSIONS: We identified a mutation in CALM1 underlying IVF manifesting in childhood and adolescence. The causality of the mutation is supported by previous studies demonstrating that F90 mediates the direct interaction of CaM with target peptides. Our approach highlights the utility of exome sequencing in uncovering the genetic defect even in families with a small number of affected individuals.

Do the Sleeping Beauty or the piggyBac transposons have higher transposition efficiency?

Compared with Sleeping Beauty, PiggyBac exhibits higher transposition efficiencies.

In this study, we compared the genomic integration efficiencies and transposition site preferences of Sleeping Beauty (SB or SB11), Tol2, and piggyBac (PB) transposon systems in primary T cells derived from peripheral blood lymphocytes (PBL) and umbilical cord blood (UCB). We found that PB demonstrated the highest efficiency of stable gene transfer in PBL-derived T cells, whereas SB11 and Tol2 mediated intermediate and lowest efficiencies, respectively. Southern hybridization analysis demonstrated that PB generated the highest number of integrants when compared to SB and Tol2 in both PBL and UCB T cells. Tol2 and PB appeared more likely to promote clonal expansion than SB, which may be in part due to the dysregulated expression of cancer-related genes near the insertion sites. Genome-wide integration analysis demonstrated that SB, Tol2, and PB integrations occurred in all the chromosomes without preference. Additionally, Tol2 and PB integration sites were mainly localized near transcriptional start sites (TSSs), CpG islands and DNaseI hypersensitive sites, whereas SB integrations were randomly distributed. These results suggest that SB may be a preferential choice of the delivery vector in T cells due to its random integration site preference and relatively high efficiency, and support continuing development of SB-mediated T-cell phase I trials. Transposons have been promising elements for gene integration, and the Sleeping Beauty (SB) system has been the major one for many years, although there have been several other transposon systems available, for example, Tol2. However, recently another system known as PiggyBac (PB) has been introduced and developed for fulfilling the same purposes, for example, mutagenesis, transgenesis and gene therapy and in some cases with improved transposition efficiency and advantages over the Sleeping Beauty transposon system, although improved hyperactive transposase has highly increased the transposition efficacy for SB. The PB systems have been used in many different scientific research fields; therefore, the purpose of this review is to describe some of these versatile uses of the PiggyBac system to give readers an overview on the usage of PiggyBac system. The generation of induced pluripotent stem (iPS) cells represents a promising approach for innovative cell therapies. The original method requires viral transduction of several reprogramming factors, which may be associated with an increased risk of tumorigenicity. Transposition of reprogramming cassettes represents a recent alternative to viral approaches. Since binary transposons can be produced as common plasmids they provide a safe and cost-efficient alternative to viral delivery methods. Here, we compared the efficiency of two different transposon systems, Sleeping Beauty (SB) and piggyBac (PB), for the generation of murine iPS. Murine fibroblasts derived from an inbred BL/6 mouse line carrying a pluripotency reporter, Oct4-EGFP, and fibroblasts derived from outbred NMRI mice were employed for reprogramming. Both transposon systems resulted in the successful isolation of murine iPS cell lines. The reduction of the core reprogramming factors to omit the proto-oncogene c-Myc was compatible with iPS cell line derivation, albeit with reduced reprogramming efficiencies. The transposon-derived iPS cells featured typical hallmarks of pluripotency, including teratoma growth in immunodeficient mice. Thus SB and PB transposons represent a promising non-viral approach for iPS cell derivation.

Where does TORC1 sequester during heat stress?

Upon heat stress, TORC1 is recruited to stress granules.

The target of rapamycin complex 1 (TORC1) is a central kinase that coordinates nutrient availability with eukaryotic cell growth. Although TORC1 signaling is repressed by various stresses in yeast, the underlying mechanisms remain elusive. Here we report that TORC1 signaling upon heat stress is regulated by stress granules (SGs), which are cytoplasmic foci formed under certain stresses. Ectopic formation of SGs achieved by Pbp1 overexpression in unstressed cells sequesters TORC1 in this compartment, thereby blunting TORC1 signaling. Upon heat stress, a physiological SG-inducing condition, TORC1 is also recruited to SGs, which delays reactivation of TORC1 signaling during recovery from heat stress. Moreover, TORC1 reactivation is directed through SG disassembly, suggesting that SGs act as a key determit for TORC1 reactivation during recovery from heat stress. Furthermore, this mechanism contributes to reduction of heat-induced mutations. Thus, TORC1 signaling is coupled to heat-induced SGs to protect cells from DNA damage.

Is rivaroxaban metabolized in kidneys?

rivaroxaban undergoes renal metabolism

Rivaroxaban is a novel, oral, direct factor Xa inhibitor for the prevention and treatment of thromboembolic disorders. The objective of this study was to investigate the in vivo metabolism and excretion of rivaroxaban in rats, dogs, and humans. Single doses of [(14)C]rivaroxaban (3 and 1 mg/kg) were administered to rats (orally/intravenously) and dogs (orally), respectively. A single oral dose of [(14)C]rivaroxaban (10 mg) was administered to healthy human males (n = 4). Plasma and excreta were collected and profiled for radioactivity. Recovery of total radioactivity was high and > or = 92% in all species. Unchanged rivaroxaban was the major compound in plasma at all time points investigated, across all species. No major or pharmacologically active circulating metabolites were detected. Rivaroxaban and its metabolites were rapidly excreted; urinary excretion of radioactivity was 25 and 52%, and fecal excretion was 67 and 43% of the dose in rats and dogs, respectively. In humans, 66% of the dose was excreted renally (36% unchanged drug) and 28% in the feces. Radioactivity profiles in excreta were similar across species. Three metabolic pathways were identified: oxidative degradation of the morpholinone moiety (major pathway) and hydrolysis of the central amide bond and of the lactam amide bond in the morpholinone ring (minor pathways). M-1, the main metabolite in excreta of all species, was eliminated via both renal and fecal/biliary routes. In total, 82 to 89% of the dose administered was assigned to unchanged rivaroxaban and its metabolites in the excreta of rats, dogs, and humans. Dabigatran is the first available oral direct thrombin inhibitor anticoagulant. Absorption of the prodrug, dabigatran etexilate and its conversion to dabigatran is rapid (peak plasma concentrations are reached 4-6 hours following surgery, and a further 2 hours later). Its oral bioavailability is low, but shows reduced interindividual variability. Dabigatran specifically and reversibly inhibits thrombin, the key enzyme in the coagulation cascade. Studies both in healthy volunteers and in patients undergoing major orthopaedic surgery show a predictable pk/pd profile that allows for fixed-dose regimens. The anticoagulant effect correlates adequately with the plasma concentrations of the drug, demonstrating effective anticoagulation combined with a low risk of bleeding. Dabigatran is mainly eliminated by renal excretion (a fact which affects the dosage in elderly and in moderate-severe renal failure patients), and no hepatic metabolism by cytochrome P450 isoenzymes has been observed, showing a good interaction profile. Rivaroxaban will probably be the first available oral factor Xa (FXa) direct inhibitor anticoagulant drug. It produces a reversible and predictable inhibition of FXa activity with potential to inhibit clot-bound FXa. Its pharmacokinetic characteristics include rapid absorption, high oral availability, high plasma protein binding and a half-life of aprox. 8 hours. Rivaroxaban elimination is mainly renal, but also through faecal matter and by hepatic metabolism. Although the drug has demonstrated moderate potential to interact with strong CYP3A4 inhibitors, it does not inhibit or induce any major CYP450 enzyme. Amongst numerous promising anticoagulant molecules, rivaroxaban (Xarelto(®)), dabigatran (Pradaxa(®)) and apixaban (Eliquis(®)) have been registered outside the USA in the prevention of thromboembolic events in patients undergoing total hip or knee prosthetic replacement. Rivaroxaban however has been granted authorisation by the FDA for the thromboprophylaxis after surgery for total hip or knee surgery. Dabigatran has been granted authorisation by the FDA in non-valvular atrial fibrillation (RE-LY trial) while rivaroxaban is expecting approval in this same indication (ROCKET trial). Phase III results in the treatment and in the secondary prevention of established venous thrombosis and pulmonary embolism are encouraging. These small molecules are obtained by chemical synthesis, their molecular weight is lower than 500 daltons. Many coagulation tests may be affected by these molecules. Those modifications should be known in order to avoid misinterpretation of the tests but could also be used to measure plasma concentrations of these products. The choice of a non specific global and readily available test has been documented (Quick time for rivaroxaban and aPTT for dabigatran). Anti-Xa (for rivaroxaban) and anti-IIa (for dabigatran) activities should however be preferred, expressed in ng/ml with calibrated plasmas (containing predetermined concentration of the tested drug). The half-life is around 8 to 12 hours, with a peak activity 2 to 4 hours after ingestion. Dabigatran is mainly eliminated via the kidney, hence requiring dose-adjustment in case of moderate renal insufficiency, and contra-indicated in case of severe renal insufficiency. Rivaroxaban being excreted via kidney and liver, some precautions should apply in case of liver insufficiency. No data are available in pregcy or pediatrics, clinical trials are ongoing. There are few interactions with concomitant drugs, which should not be ignored. The short half-life of these new agents compensates for the lack of any specific antidote in many instances. Their oral administration, without the need for dose adjustment, and without requirement for a laboratory monitoring will increase their use in a large number of patients, in those indications for which an approval has been granted by health authorities. Atrial fibrillation is an important cause of preventable, disabling stroke and is particularly frequent in patients with chronic kidney disease (CKD). Stage 3 CKD is an independent risk factor for stroke in patients with atrial fibrillation. Warfarin anticoagulation is efficacious for stroke prevention in atrial fibrillation patients with stage 3 CKD, but recent observational studies have challenged its value for patients with end-stage renal disease and atrial fibrillation. Novel oral anticoagulants such as dabigatran, apixaban and rivaroxaban are at least as efficacious as warfarin with reduced risks of intracranial haemorrhage. However, all these agents undergo renal clearance to varying degrees, and hence dosing, efficacy, and safety require special consideration in patients with CKD. Overall, the novel oral anticoagulants have performed well in randomized trials of patients with stage 3 CKD, with similar efficacy and safety profiles as for patients without CKD, albeit requiring dosing modifications. The required period of discontinuation of novel oral anticoagulants before elective surgery is longer for patients with CKD owing to their reduced renal clearance. Although much remains to be learned about the optimal use of these new agents in patients with CKD, they are attractive anticoagulation options that are likely to replace warfarin in coming years. The incidence and prevalence of atrial fibrillation are quickly increasing, mainly due to the ageing of the population. Atrial fibrillation is, to date, a problem of public health. Atrial fibrillation is associated to a five-fold risk of stroke, which may be identified by score risks, such as CHADS(2) score. The classical antithrombotic treatment of atrial fibrillation is based on vitamin K antagonists. Trials made in the 90's have clearly shown that vitamin K antagonists were able to decrease stroke risk by about 60%. New oral anticoagulants are now available on the market to treat patients with atrial fibrillation. These drugs are dabigatran which has demonstrated an interest in the RE-LY trial. Two doses may be prescribed, 110 mg bid and 150 mg bid. Anti Xa have also demonstrated an interest : rivaroxaban in the ROCKET AF trial and apixaban in the AVERROES (versus aspirin) and ARISTOTLE trials. In the future these drugs will have a major place in the armamentarium used to treat patients with atrial fibrillation. In all these trials a decrease in intra cranial haemorrhages has been demonstrated. In the everyday practice it will be necessary to be very cautious in patients with impaired renal function, as all these drugs are eliminated by kidneys. Elderly people more than 70 years develop atrial fibrillation that causes stroke and heart failure. Furthermore, the elderly people who have atrial fibrillation accompany many risk factor, and develop cerebral infarction easily. Therefore, it is very important to prevent cerebral infarction using anticoagulant drugs. So far we usually use warfarin, which has many limitations, especially cerebral bleeding. Now new anticoagulant drugs(dabigatran and rivaroxaban) can become available. Therefore, we have to learn how to use those drugs. They have to carefully be used because they discharge from kidney and old aged patients have potential renal dysfunction. We mainly explain anticoagulant therapy in old aged patients. Chronic kidney disease and atrial fibrillation (AF) commonly coexist, and data suggest that renal patients have AF rates in excess of double that encountered in the general population. These patients are at increased risk of stroke, regardless of the presence or absence of AF. Furthermore, a lower GFR causes increased thromboembolic risk in patients with AF - independent of other risk factors. The dilemma facing clinicians treating this cohort of patients is that renal insufficiency confers both a thromboembolic and a bleeding risk. Renal disease also commonly coexists with other risk factors for stroke and bleeding such as hypertension and advanced age. Furthermore, bleeding risk tracks stroke risk and many risk factors are common to both thromboembolism and haemorrhage. Patients with severe renal impairment are also actively excluded from the majority of trials for stroke prevention in AF, including those trials which informed the development of stroke risk factor scoring schemes. Therefore, patients with renal disease and AF present a unique management challenge. The available data suggests that the benefit from warfarin in terms of stroke reduction is not as clear as in the general population, and there is an increased risk of bleeding complications and even ectopic vascular calcification. Thus, it is problematic to extrapolate the benefits of warfarin in the general population to a subgroup that has been actively excluded from clinical trials. The new oral anticoagulants have relatively little data in patients with severe renal impairment, and all have an element of renal excretion. There is a need for large randomised control trials in patients with renal insufficiency and on haemodialysis to provide a bank of high-quality scientific data on which clinicians can base their management decisions. Until then, we must adopt a pragmatic approach which involves careful consideration of the relative risk of stroke and bleeding in each individual patient. Chronic kidney disease (CKD) is prevalent in elderly patients with atrial fibrillation and is an independent risk factor for stroke. Warfarin anticoagulation is efficacious for stroke prevention in atrial fibrillation patients with moderate CKD (stage III, estimated glomerular filtration rate 30-59 mL/min), but recent observational studies have challenged its value for patients with end-stage renal disease requiring dialysis. The novel oral anticoagulants (i.e., dabigatran, apixaban, rivaroxaban) all undergo renal metabolism to varying degrees, and hence dosing, efficacy, and safety require special consideration in CKD patients. In randomized trials to date involving 11,169 patients with moderate CKD, the novel oral anticoagulants performed well, with similar efficacy and safety profiles as for non-CKD patients. For atrial fibrillation patients with stage III CKD, the available data are strongest for dabigatran 150 mg twice daily as superior to warfarin for stroke prevention and for apixaban as superior to warfarin regarding reduced major hemorrhage. Renal function should be monitored at least annually in patients receiving a novel oral anticoagulant, and more often in elderly patients and those with underlying CKD or comorbidities who are at special risk for dehydration and deterioration of renal function. Much remains to be learned about the optimal use of the novel oral anticoagulants in CKD patients; additional studies about optimal dosing of the novel oral anticoagulants and frequency of monitoring renal function in CKD patients with atrial fibrillation are needed. Anticoagulation options for hemodialysis patients require testing in randomized trials.

What are the side effects of Nalmefene?

Side effects of nalmefene include nausea, dizziness / lightheadedness, insomina, fatigue, vomiting, reduced caloric intake / apetite, increased self-rated alertness and decreased tiredness. In horses some passage of semifluid fecal material, intermittent penile relaxation, and mild sedation has been described. In some studies nalmefene was well tolerated by all subjects, and no clinically significant adverse effects were observed.

Effects of nalmefene on eating were investigated in two groups of ten male volunteers, in a double-blind placebo-controlled study. The nalmefene treated group ate 22% less, both in terms of absolute weight and caloric intake, of a standardised buffet-meal than did the placebo group. No differences in subjective ratings of hunger or satiety were found between the groups, suggesting that the reduced feeding was not a consequence of any change in motivation to eat. When analysed by nutrient content, nalmefene was found to reduce fat and protein, but not carbohydrate, intakes. Analyses of intakes of individual foods showed a differential effect of nalmefene on foods rated as highly palatable. Thus the apparent nutrient specificity of nalmefene appeared to be an indirect consequence of its effect on palatability. Nalmefene also caused slight increases in self-rated alertness, and decreases in ratings of tiredness and elation, although it was thought unlikely that these accounted for observed changes in eating behaviour. No other side-effects were detected, and performance on a choice reaction time task was unaffected. These results add weight to suggestions that endogenous opioids are involved in reward-related aspects of feeding associated with food palatability. The aim of these two studies was to evaluate the safety and pharmacokinetics of oral nalmefene, a new orally effective opioid antagonist. In the first study, single ascending doses of 50, 100, 200, and 300 mg of nalmefene HCl were administered in double-blind fashion to four groups of healthy men. There were six subjects in each group; four received nalmefene and two received placebo. The drug was well tolerated at all dose levels with only mild and transient side effects, such as lightheadedness, at the higher doses. Model-independent pharmacokinetic analysis of the plasma concentration-time data showed that nalmefene was rapidly absorbed and had an elimination half-life that ranged from seven to 15 hours (mean, 10.7 hr). There was a good linear relationship (r = .97) between administered dose and total area under the curve at each dose level. Only about 4% of the dose was excreted in the urine as unchanged nalmefene, whereas up to 60% was excreted as a beta-glucuronidase/sulfatase hydrolysable conjugate(s) of nalmefene. In the second study, six healthy men were initially administered a single 50-mg dose of drug, and plasma samples were obtained at selected time intervals for 48 hours. A dosing schedule of 20 mg q12h was then started and continued for seven days. Plasma samples were collected immediately before each dose and at selected times for up to 48 hours after the last dose. The drug was well tolerated by all subjects, and no clinically significant adverse effects were observed during the seven-day administration period.(ABSTRACT TRUNCATED AT 250 WORDS) Crib-biting in horses is a repetitive behavior pattern which may involve the activation of both narcotic receptors and dopamine receptors in the CNS. Crib-biting frequency, determined in 7 nontreated horses under controlled conditions, was usually linear for many hours and ranged from 0.3 to 14.9 bites/min. Intravenous or IM injections of narcotic antagonists decreased these rates to almost zero by about 20 minutes after the injection was given. The duration of the response to a single injection ranged from 20 minutes for naloxone to 4 hours or more for nalmefene and diprenorphine. Effective doses were 0.02 to 0.04 mg of naloxone/kg, 0.04 mg of naltrexone/kg, 0.08 mg of nalmefene/kg, and 0.02 to 0.03 mg of diprenorphine/kg. Crib-biting could be prevented completely for up to a week by continuous infusion of 5 to 10 mg of nalmefene/hr. Crib-biting resumed when the infusion was discontinued, and plasma nalmefene concentrations decreased to below 5 ng/ml. Doses of nalmefene as large as 0.4 mg/kg, IV, produced only minor side effects. These side effects included some passage of semifluid fecal material, intermittent penile relaxation, and mild sedation. Treated horses responded normally to external stimuli, retained their appetites, and performed appropriately when ridden. Sedation wore off during the course of prolonged infusions. Narcotic antagonists may provide a novel and effective treatment of stereotypic behavior disorders. In a placebo-controlled, double-blind study we evaluated the safety and kinetics of a new narcotic antagonist, nalmefene, after 2, 6, 12, and 24 mg intravenous doses to healthy men. At each dose level four subjects received active drug and two received placebo. The drug was well tolerated at all dose levels with only mild and transient side effects, the most common of which was lightheadedness. The plasma concentration-time data were best fit with a triexponential equation, and the terminal elimination phase had a harmonic mean t1/2 of 8 to 9 hours. Only about 5% of the dose was excreted in the urine as intact nalmefene, with up to 60% excreted as nalmefene glucuronide. Although intersubject differences were noted, mean or dose-normalized mean kinetic parameters such as clearance, steady-state volume of distribution, terminal t1/2, and AUC showed no consistent trends related to increasing doses, indicating that nalmefene has linear pharmacokinetics. OBJECTIVE: Pathological gambling is a disabling disorder experienced by approximately 1%-2% of adults and for which there are few empirically validated treatments. The authors examined the efficacy and tolerability of the opioid antagonist nalmefene in the treatment of adults with pathological gambling. METHOD: A 16-week, randomized, dose-ranging, double-blind, placebo-controlled trial was conducted at 15 outpatient treatment centers across the United States between March 2002 and April 2003. Two hundred seven persons with DSM-IV pathological gambling were randomly assigned to receive nalmefene (25 mg/day, 50 mg/day, or 100 mg/day) or placebo. Scores on the primary outcome measure (Yale-Brown Obsessive Compulsive Scale Modified for Pathological Gambling) were analyzed by using a linear mixed-effects model. RESULTS: Estimated regression coefficients showed that the 25 mg/day and 50 mg/day nalmefene groups had significantly different scores on the Yale-Brown Obsessive Compulsive Scale Modified for Pathological Gambling, compared to the placebo group. A total of 59.2% of the subjects who received 25 mg/day of nalmefene were rated as "much improved" or "very much improved" at the last evaluation, compared to 34.0% of those who received placebo. Adverse experiences included nausea, dizziness, and insomnia. CONCLUSIONS: Subjects who received nalmefene had a statistically significant reduction in severity of pathological gambling. Low-dose nalmefene (25 mg/day) appeared efficacious and was associated with few adverse events. Higher doses (50 mg/day and 100 mg/day) resulted in intolerable side effects.

Is Hirschsprung disease one of the characteristics of the Mowat-Wilson syndrome?

Mowat-Wilson syndrome is characterized by typical facial features, moderate-to-severe mental retardation, epilepsy and variable congenital malformations, including Hirschsprung disease, genital anomalies, congenital heart disease, agenesis of the corpus callosum, and eye defects.

We report a girl who had Hirschsprung disease in association with distinct facial appearance, microcephaly, agenesis of the corpus callosum and mental retardation (Mowat-Wilson syndrome). Mutation analysis of the zinc finger homeo box 1 B (ZFHX1 B) gene revealed a de novo 7 bp deletion (TGGCCCC) at nucleotide 1773 (1773 delTGGCCCC) resulting in a frameshift and leading to a termination codon at amino acid residue 604 (604 X) in exon 8 C. The zinc finger homeo box 1 B (Smad interacting protein-1) is a transcription corepressor of Smad target genes with functions in the patterning of neural crest derived cells, CNS, and midline structures. Mutations in ZFHX1 B can lead to neurological disorders in addition to dysmorphic features, megacolon, and other malformations. Hypospadias, when the urethra opens on the ventral side of the penis, is a common malformation seen in about 3 per 1,000 male births. It is a complex disorder associated with genetic and environmental factors and can be part of genetic syndromes. Mowat-Wilson syndrome (MWS) is a multiple congenital anomaly syndrome characterized by a distinct facial phenotype, Hirschsprung disease, microcephaly and mental retardation. It is caused by mutations in the zinc finger homeo box 1B gene, ZFHX1B (SIP1). To date, 68 deletion/mutation-positive cases have been reported. Genitourinary anomalies are common in MWS. Here we report that hypospadias is common in males with this syndrome. In 39 patients where this information was available, hypospadias was present in 46% of patients (18/39). In the 3 Italian male cases reported here, hypospadias was always present. MWS should be considered by endocrinologists in patients with hypospadias associated with developmental delays/mental retardation, in particular in the presence of a distinct facial phenotype. BACKGROUND/PURPOSE: Patients with zinc finger homeo box 1B (ZFHX1B) mutations or deletions develop multiple congenital anomalies including Hirschsprung disease, known as Mowat-Wilson syndrome (MWS). In this study, we investigated variations in the enteric neural plexus abnormalities in MWS using morphometry-based histopathologic analysis. METHODS: Seven patients with MWS (3 with mutations in exon 8 of ZFHX1B and 4 with deletions) who had undergone modified Duhamel's operations for Hirschsprung disease were examined. Surgically resected rectosigmoid specimens were analyzed morphometrically. RESULTS: The length of the aganglionic segment was longer than 3 cm in all the patients with deletions. In 3 patients with mutations, the aganglionic region was not detected in the surgically resected specimens; however, the parameters of the ganglions and plexus were significantly smaller than those of controls (cloaca and aproctia), indicative of a transitional zone. Variation in the severity of pathological changes among the 3 patients with mutations was also noted. CONCLUSIONS: The variations in myenteric plexus pathologies in MWS appear to be caused by both variations in ZFHX1B abnormalities and epigenetic factors. Mowat-Wilson syndrome (MWS) is a multiple congenital anomaly syndrome characterized by a distinct facial phenotype (high forehead, frontal bossing, large eyebrows, medially flaring and sparse in the middle part, hypertelorism, deep set but large eyes, large and uplifted ear lobes, with a central depression, saddle nose with prominent rounded nasal tip, prominent columella, open mouth, with M-shaped upper lip, frequent smiling, and a prominent but narrow and triangular pointed chin), moderate-to-severe intellectual deficiency, epilepsy and variable congenital malformations including Hirschsprung disease (HSCR), genitourinary anomalies (in particular hypospadias in males), congenital heart defects, agenesis of the corpus callosum and eye anomalies. The prevalence of MWS is currently unknown, but 171 patients have been reported so far. It seems probable that MWS is under-diagnosed, particularly in patients without HSCR. MWS is caused by heterozygous mutations or deletions in the Zinc finger E-box-binding homeobox 2 gene, ZEB2, previously called ZFHX1B (SIP1). To date, over 100 deletions/mutations have been reported in patients with a typical phenotype; they are frequently whole gene deletions or truncating mutations, suggesting that haploinsufficiency is the main pathological mechanism. Studies of genotype-phenotype analysis show that facial gestalt and delayed psychomotor development are constant clinical features, while the frequent and severe congenital malformations are variable. In a small number of patients, unusual mutations can lead to an atypical phenotype. The facial phenotype is particularly important for the initial clinical diagnosis and provides the hallmark warranting ZEB2 mutational analysis, even in the absence of HSCR. The majority of MWS cases reported so far were sporadic, therefore the recurrence risk is low. Nevertheless, rare cases of sibling recurrence have been observed. Congenital malformations and seizures require precocious clinical investigation with intervention of several specialists (including neonatologists and pediatricians). Psychomotor development is delayed in all patients, therefore rehabilitation (physical therapy, psychomotor and speech therapy) should be started as soon as possible. PURPOSE: Mowat-Wilson syndrome (MWS) is a developmental disorder presenting with mental retardation, delayed motor development, and a wide spectrum of clinical features. Hirschsprung's disease (HD) is associated in almost 50% of cases. This report aims to analyze the course of HD and to evaluate the clinical outcomes of these patients. PATIENTS AND METHODS: Between 1997 and 2007, 110 patients presenting with HD were diagnosed and managed in our institution. Five of them presented the association of HD and MWS. Their records were reviewed retrospectively. RESULTS: All of the 5 patients have a genetic disorder specific of MWS (nonsense mutation or deletion on SIP1 gene, locus 2q22). Two patients underwent transanal endorectal pull-through procedure for classic rectosigmoid HD. Three patients were operated on for total colonic aganglionosis using Duhamel procedure. The median follow-up was 4 (range, 0.3-7) years. Only one patient is doing well (rectosigmoid HD). Two patients have a stoma diversion for severe motility disorders. Of the 3 total colonic aganglionosis, one still has repeated episodes of obstruction requiring total parenteral nutrition (TPN). The 2 others still have repeated episodes of enterocolitis. All patients required a prolonged TPN (32.5 months in average). CONCLUSION: Hirschsprung's disease associated with MWS is a severe condition. Even in case of short segment HD, patients can present motility disorder requiring a prolonged TPN. Physician and surgeon should be aware about the evolution of this rare condition. We present a clinical case of a female infant with multiple anomalies and distinctive facial features, with an exceptionally severe clinical course of Hirschsprung disease. The girl was also diagnosed with Mowat-Wilson syndrome, confirmed by molecular analysis as a heterozygous deletion of the ZEB2 gene. Moreover, molecular karyotyping revealed a deletion involving further genes (KYNU, ARHGAP15, and GTDC1). Mowat-Wilson syndrome (MWS) is an autosomal domit intellectual disability syndrome characterised by unique facial features and congenital anomalies such as Hirschsprung disease, congenital heart defects, corpus callosum agenesis and urinary tract anomalies. Some cases also present epilepsy, growth retardation and microcephaly. The syndrome is caused by mutations or deletions of the ZEB2 gene at chromosome 2q22-q23. MWS was first described in 1998 and until now approximately 180 cases have been reported worldwide. We report the first three molecularly confirmed Danish cases with MWS. Mowat-Wilson syndrome is a mental retardation-multiple congenital anomaly syndrome characterized by a typical facies, developmental delay, epilepsy, and variable congenital malformations, including Hirschsprung disease, urogenital anomalies, congenital heart disease, and agenesis of the corpus callosum. This disorder is sporadic and is caused by heterozygous mutations or deletions of the ZFHX1B gene located in the 2q22 region. We report here the first Moroccan patient, born to consanguineous parents, with Mowat-Wilson syndrome, due to a de novo, unreported mutation of the ZFHX1B gene. Mowat-Wilson syndrome is a genetic disorder characterized by a distinct facial appearance, moderate-to-severe mental retardation, microcephaly, agenesis of the corpus callosum, Hirschsprung disease, congenital heart disease, and genital anomalies. Ophthalmological abnormalities have been rarely described in patients with this condition which is caused by mutations in the ZEB2 gene. We report a 9-year-old female with this syndrome who has severe ocular abnormalities including bilateral microphthalmia, cataract, and retinal aplasia. Mowat-Wilson syndrome (MWS) is a severe intellectual disability (ID)-distinctive facial gestalt-multiple congenital anomaly syndrome, commonly associating microcephaly, epilepsy, corpus callosum agenesis, conotruncal heart defects, urogenital malformations and Hirschsprung disease (HSCR). MWS is caused by de novo heterozygous mutations in the ZEB2 gene. The majority of mutations lead to haplo-insufficiency through premature stop codons or large gene deletions. Only three missense mutations have been reported so far; none of which resides in a known functional domain of ZEB2. In this study, we report and analyze the functional consequences of three novel missense mutations, p.Tyr1055Cys, p.Ser1071Pro and p.His1045Arg, identified in the highly conserved C-zinc-finger (C-ZF) domain of ZEB2. Patients' phenotype included the facial gestalt of MWS and moderate ID, but no microcephaly, heart defects or HSCR. In vitro studies showed that all the three mutations prevented binding and repression of the E-cadherin promoter, a characterized ZEB2 target gene. Taking advantage of the zebrafish morphant technology, we performed rescue experiments using wild-type (WT) and mutant human ZEB2 mRNAs. Variable, mutation-dependent, embryo rescue, correlating with the severity of patients' phenotype, was observed. Our data provide evidence that these missense mutations cause a partial loss of function of ZEB2, suggesting that its role is not restricted to repression of E-cadherin. Functional domains other than C-ZF may play a role in early embryonic development. Finally, these findings broaden the clinical spectrum of ZEB2 mutations, indicating that MWS ought to be considered in patients with lesser degrees of ID and a suggestive facial gestalt, even in the absence of congenital malformation. Mowat-Wilson syndrome is a genetic disease characterized by typical facial features, Hirschsprung disease and multiple congenital abnormalities. MWS is a single gene disorder. One of the most specific clinical signs in MWS is the distinctive face. We report a two-year-old boy with multiple congenital anomalies. He had peripupillary atrophy and gingival hypertrophy different from the literature. The patient was also diagnosed with his clinical findings. These features may be important in Mowat-Wilson syndrome and clinicians should keep these findings in mind. Individuals with Mowat-Wilson syndrome (MWS; OMIM#235730) have characteristic facial features, a variety of congenital anomalies such as Hirschsprung disease, and intellectual disabilities caused by mutation or deletion of ZEB2 gene. This deletion or cytogenetic abnormality has been reported primarily from Europe, Australia and the United States, but not in Korea. Here we report a patient with characteristic facial features of MWS, developmental delay and spasticity. High resolution microarray analysis revealed 0.9 Mb deletion of 2q22.3 involving two genes: ZEB2 and GTDC1. This case shows the important role of high resolution microarray in patients with unexplained psychomotor retardation and/or facial dysmorphism. Knowledge about the most striking clinical signs and implementation of effective molecular tests like microarray could significantly increase the detection rate of new cases of MWS in Korea. This is the first reported case of MWS in Korea. Mowat-Wilson syndrome is a genetic disease caused by heterozygous mutations or deletions of the zinc finger E-box-binding homeobox 2 (ZEB2) gene. The syndrome is characterized by typical facial features, moderate-to-severe mental retardation, epilepsy and variable congenital malformations, including Hirschsprung disease, genital anomalies, congenital heart disease, agenesis of the corpus callosum, and eye defects. The prevalence of Mowat-Wilson syndrome is currently unknown, but it seems that Mowat-Wilson syndrome is underdiagnosed, particularly in patients without Hirschsprung disease. We report here the first Egyptian case of Mowat-Wilson syndrome who was conceived by intracytoplasmic sperm injection. The patient manifested bilateral sensorineural hearing loss--a new feature not previously reported in cases of Mowat-Wilson syndrome. This report describes the first Egyptian patient of Mowat-Wilson syndrome who was conceived after intracytoplasmic sperm injection, and provides a new evidence for the inclusion of deafness among the congenital defects of the syndrome.

Which are the most common methods for gene prioritization analysis?

Functional annotation-based approaches and literature-based approaches have been initially used. In recent years, network-based methods - which utilize a knowledge network derived from biological knowledge - have been utilized for gene prioritization. Currently network-based methods are the ones most widely used.

The identification of genes involved in health and disease remains a challenge. We describe a bioinformatics approach, together with a freely accessible, interactive and flexible software termed Endeavour, to prioritize candidate genes underlying biological processes or diseases, based on their similarity to known genes involved in these phenomena. Unlike previous approaches, ours generates distinct prioritizations for multiple heterogeneous data sources, which are then integrated, or fused, into a global ranking using order statistics. In addition, it offers the flexibility of including additional data sources. Validation of our approach revealed it was able to efficiently prioritize 627 genes in disease data sets and 76 genes in biological pathway sets, identify candidates of 16 mono- or polygenic diseases, and discover regulatory genes of myeloid differentiation. Furthermore, the approach identified a novel gene involved in craniofacial development from a 2-Mb chromosomal region, deleted in some patients with DiGeorge-like birth defects. The approach described here offers an alternative integrative method for gene discovery. MOTIVATION: Hunting disease genes is a problem of primary importance in biomedical research. Biologists usually approach this problem in two steps: first a set of candidate genes is identified using traditional positional cloning or high-throughput genomics techniques; second, these genes are further investigated and validated in the wet lab, one by one. To speed up discovery and limit the number of costly wet lab experiments, biologists must test the candidate genes starting with the most probable candidates. So far, biologists have relied on literature studies, extensive queries to multiple databases and hunches about expected properties of the disease gene to determine such an ordering. Recently, we have introduced the data mining tool ENDEAVOUR (Aerts et al., 2006), which performs this task automatically by relying on different genome-wide data sources, such as Gene Ontology, literature, microarray, sequence and more. RESULTS: In this article, we present a novel kernel method that operates in the same setting: based on a number of different views on a set of training genes, a prioritization of test genes is obtained. We furthermore provide a thorough learning theoretical analysis of the method's guaranteed performance. Finally, we apply the method to the disease data sets on which ENDEAVOUR (Aerts et al., 2006) has been benchmarked, and report a considerable improvement in empirical performance. AVAILABILITY: The MATLAB code used in the empirical results will be made publicly available. BACKGROUND: Genes that are co-expressed tend to be involved in the same biological process. However, co-expression is not a very reliable predictor of functional links between genes. The evolutionary conservation of co-expression between species can be used to predict protein function more reliably than co-expression in a single species. Here we examine whether co-expression across multiple species is also a better prioritizer of disease genes than is co-expression between human genes alone. RESULTS: We use co-expression data from yeast (S. cerevisiae), nematode worm (C. elegans), fruit fly (D. melanogaster), mouse and human and find that the use of evolutionary conservation can indeed improve the predictive value of co-expression. The effect that genes causing the same disease have higher co-expression than do other genes from their associated disease loci, is significantly enhanced when co-expression data are combined across evolutionarily distant species. We also find that performance can vary significantly depending on the co-expression datasets used, and just using more data does not necessarily lead to better prioritization. Instead, we find that dataset quality is more important than quantity, and using a consistent microarray platform per species leads to better performance than using more inclusive datasets pooled from various platforms. CONCLUSION: We find that evolutionarily conserved gene co-expression prioritizes disease candidate genes better than human gene co-expression alone, and provide the integrated data as a new resource for disease gene prioritization tools. Endeavour (http://www.esat.kuleuven.be/endeavourweb; this web site is free and open to all users and there is no login requirement) is a web resource for the prioritization of candidate genes. Using a training set of genes known to be involved in a biological process of interest, our approach consists of (i) inferring several models (based on various genomic data sources), (ii) applying each model to the candidate genes to rank those candidates against the profile of the known genes and (iii) merging the several rankings into a global ranking of the candidate genes. In the present article, we describe the latest developments of Endeavour. First, we provide a web-based user interface, besides our Java client, to make Endeavour more universally accessible. Second, we support multiple species: in addition to Homo sapiens, we now provide gene prioritization for three major model organisms: Mus musculus, Rattus norvegicus and Caenorhabditis elegans. Third, Endeavour makes use of additional data sources and is now including numerous databases: ontologies and annotations, protein-protein interactions, cis-regulatory information, gene expression data sets, sequence information and text-mining data. We tested the novel version of Endeavour on 32 recent disease gene associations from the literature. Additionally, we describe a number of recent independent studies that made use of Endeavour to prioritize candidate genes for obesity and Type II diabetes, cleft lip and cleft palate, and pulmonary fibrosis. MOTIVATION: Computational gene prioritization methods are useful to help identify susceptibility genes potentially being involved in genetic disease. Recently, text mining techniques have been applied to extract prior knowledge from text-based genomic information sources and this knowledge can be used to improve the prioritization process. However, the effect of various vocabularies, representations and ranking algorithms on text mining for gene prioritization is still an issue that requires systematic and comparative studies. Therefore, a benchmark study about the vocabularies, representations and ranking algorithms in gene prioritization by text mining is discussed in this article. RESULTS: We investigated 5 different domain vocabularies, 2 text representation schemes and 27 linear ranking algorithms for disease gene prioritization by text mining. We indexed 288 177 MEDLINE titles and abstracts with the TXTGate text pro.ling system and adapted the benchmark dataset of the Endeavour gene prioritization system that consists of 618 disease-causing genes. Textual gene pro.les were created and their performance for prioritization were evaluated and discussed in a comparative manner. The results show that inverse document frequency-based representation of gene term vectors performs better than the term-frequency inverse document-frequency representation. The eVOC and MESH domain vocabularies perform better than Gene Ontology, Online Mendelian Inheritance in Man's and London Dysmorphology Database. The ranking algorithms based on 1-SVM, Standard Correlation and Ward linkage method provide the best performance. AVAILABILITY: The MATLAB code of the algorithm and benchmark datasets are available by request. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online. PURPOSE: We present an approach to prioritize single nucleotide polymorphisms for further follow-up in genome-wide association studies of type 2 diabetes. METHOD: The proposed method combines both the use of open data access from two type 2 diabetes-genome-wide association studies (granted by the Diabetes Genetics Initiative and the Welcome Trust Case Control Consortium) and the comprehensive analysis of candidate regions generated by the freely accessible ENDEAVOUR software. RESULTS: The algorithm prioritized all genes of the whole genome in relation to type 2 diabetes. There were six of 1096 single nucleotide polymorphisms in five genes potentially associated with type 2 diabetes: tachykinin receptor 3 (rs1384401), anaplastic lymphoma receptor tyrosine kinase (rs4319896), calcium channel, voltage-dependent, L type, alpha 1D subunit (rs12487452), FOXO1A (rs10507486 and rs7323267), and v-akt murine thymoma viral oncogene homolog 3 (rs897959). We estimated the fixed effect and P values of each single nucleotide polymorphism in the combined dataset by Mantel-Haenszel meta-analysis and we observed significant P values for all single nucleotide polymorphisms except for rs897959 at v-akt murine thymoma viral oncogene homolog 3. CONCLUSION: The proposed strategy may be used as an alternative tool for optimizing the information of the nearly 500,000 gene variants in which markers with modest significant P value for disease association are currently disregarded. Additionally, the said single nucleotide polymorphisms may be incorporated into the replication of the multistage design involved in the genome-wide association studies. ToppGene Suite (http://toppgene.cchmc.org; this web site is free and open to all users and does not require a login to access) is a one-stop portal for (i) gene list functional enrichment, (ii) candidate gene prioritization using either functional annotations or network analysis and (iii) identification and prioritization of novel disease candidate genes in the interactome. Functional annotation-based disease candidate gene prioritization uses a fuzzy-based similarity measure to compute the similarity between any two genes based on semantic annotations. The similarity scores from individual features are combined into an overall score using statistical meta-analysis. A P-value of each annotation of a test gene is derived by random sampling of the whole genome. The protein-protein interaction network (PPIN)-based disease candidate gene prioritization uses social and Web networks analysis algorithms (extended versions of the PageRank and HITS algorithms, and the K-Step Markov method). We demonstrate the utility of ToppGene Suite using 20 recently reported GWAS-based gene-disease associations (including novel disease genes) representing five diseases. ToppGene ranked 19 of 20 (95%) candidate genes within the top 20%, while ToppNet ranked 12 of 16 (75%) candidate genes among the top 20%. MOTIVATION: During the past decade, we have seen an exponential growth of vast amounts of genetic data generated for complex disease studies. Currently, across a variety of complex biological problems, there is a strong trend towards the integration of data from multiple sources. So far, candidate gene prioritization approaches have been designed for specific purposes, by utilizing only some of the available sources of genetic studies, or by using a simple weight scheme. Specifically to psychiatric disorders, there has been no prioritization approach that fully utilizes all major sources of experimental data. RESULTS: Here we present a multi-dimensional evidence-based candidate gene prioritization approach for complex diseases and demonstrate it in schizophrenia. In this approach, we first collect and curate genetic studies for schizophrenia from four major categories: association studies, linkage analyses, gene expression and literature search. Genes in these data sets are initially scored by category-specific scoring methods. Then, an optimal weight matrix is searched by a two-step procedure (core genes and unbiased P-values in independent genome-wide association studies). Finally, genes are prioritized by their combined scores using the optimal weight matrix. Our evaluation suggests this approach generates prioritized candidate genes that are promising for further analysis or replication. The approach can be applied to other complex diseases. AVAILABILITY: The collected data, prioritized candidate genes, and gene prioritization tools are freely available at http://bioinfo.mc.vanderbilt.edu/SZGR/. BACKGROUND: Text mining has become a useful tool for biologists trying to understand the genetics of diseases. In particular, it can help identify the most interesting candidate genes for a disease for further experimental analysis. Many text mining approaches have been introduced, but the effect of disease-gene identification varies in different text mining models. Thus, the idea of incorporating more text mining models may be beneficial to obtain more refined and accurate knowledge. However, how to effectively combine these models still remains a challenging question in machine learning. In particular, it is a non-trivial issue to guarantee that the integrated model performs better than the best individual model. RESULTS: We present a multi-view approach to retrieve biomedical knowledge using different controlled vocabularies. These controlled vocabularies are selected on the basis of nine well-known bio-ontologies and are applied to index the vast amounts of gene-based free-text information available in the MEDLINE repository. The text mining result specified by a vocabulary is considered as a view and the obtained multiple views are integrated by multi-source learning algorithms. We investigate the effect of integration in two fundamental computational disease gene identification tasks: gene prioritization and gene clustering. The performance of the proposed approach is systematically evaluated and compared on real benchmark data sets. In both tasks, the multi-view approach demonstrates significantly better performance than other comparing methods. CONCLUSIONS: In practical research, the relevance of specific vocabulary pertaining to the task is usually unknown. In such case, multi-view text mining is a superior and promising strategy for text-based disease gene identification. BACKGROUND: Discovering novel disease genes is still challenging for diseases for which no prior knowledge--such as known disease genes or disease-related pathways--is available. Performing genetic studies frequently results in large lists of candidate genes of which only few can be followed up for further investigation. We have recently developed a computational method for constitutional genetic disorders that identifies the most promising candidate genes by replacing prior knowledge by experimental data of differential gene expression between affected and healthy individuals.To improve the performance of our prioritization strategy, we have extended our previous work by applying different machine learning approaches that identify promising candidate genes by determining whether a gene is surrounded by highly differentially expressed genes in a functional association or protein-protein interaction network. RESULTS: We have proposed three strategies scoring disease candidate genes relying on network-based machine learning approaches, such as kernel ridge regression, heat kernel, and Arnoldi kernel approximation. For comparison purposes, a local measure based on the expression of the direct neighbors is also computed. We have benchmarked these strategies on 40 publicly available knockout experiments in mice, and performance was assessed against results obtained using a standard procedure in genetics that ranks candidate genes based solely on their differential expression levels (Simple Expression Ranking). Our results showed that our four strategies could outperform this standard procedure and that the best results were obtained using the Heat Kernel Diffusion Ranking leading to an average ranking position of 8 out of 100 genes, an AUC value of 92.3% and an error reduction of 52.8% relative to the standard procedure approach which ranked the knockout gene on average at position 17 with an AUC value of 83.7%. CONCLUSION: In this study we could identify promising candidate genes using network based machine learning approaches even if no knowledge is available about the disease or phenotype. BACKGROUND: Several computational candidate gene selection and prioritization methods have recently been developed. These in silico selection and prioritization techniques are usually based on two central approaches--the examination of similarities to known disease genes and/or the evaluation of functional annotation of genes. Each of these approaches has its own caveats. Here we employ a previously described method of candidate gene prioritization based mainly on gene annotation, in accompaniment with a technique based on the evaluation of pertinent sequence motifs or signatures, in an attempt to refine the gene prioritization approach. We apply this approach to X-linked mental retardation (XLMR), a group of heterogeneous disorders for which some of the underlying genetics is known. RESULTS: The gene annotation-based binary filtering method yielded a ranked list of putative XLMR candidate genes with good plausibility of being associated with the development of mental retardation. In parallel, a motif finding approach based on linear discriminatory analysis (LDA) was employed to identify short sequence patterns that may discriminate XLMR from non-XLMR genes. High rates (>80%) of correct classification was achieved, suggesting that the identification of these motifs effectively captures genomic signals associated with XLMR vs. non-XLMR genes. The computational tools developed for the motif-based LDA is integrated into the freely available genomic analysis portal Galaxy (http://main.g2.bx.psu.edu/). Nine genes (APLN, ZC4H2, MAGED4, MAGED4B, RAP2C, FAM156A, FAM156B, TBL1X, and UXT) were highlighted as highly-ranked XLMR methods. CONCLUSIONS: The combination of gene annotation information and sequence motif-orientated computational candidate gene prediction methods highlight an added benefit in generating a list of plausible candidate genes, as has been demonstrated for XLMR. BACKGROUND: High-throughput molecular interaction data have been used effectively to prioritize candidate genes that are linked to a disease, based on the observation that the products of genes associated with similar diseases are likely to interact with each other heavily in a network of protein-protein interactions (PPIs). An important challenge for these applications, however, is the incomplete and noisy nature of PPI data. Information flow based methods alleviate these problems to a certain extent, by considering indirect interactions and multiplicity of paths. RESULTS: We demonstrate that existing methods are likely to favor highly connected genes, making prioritization sensitive to the skewed degree distribution of PPI networks, as well as ascertainment bias in available interaction and disease association data. Motivated by this observation, we propose several statistical adjustment methods to account for the degree distribution of known disease and candidate genes, using a PPI network with associated confidence scores for interactions. We show that the proposed methods can detect loosely connected disease genes that are missed by existing approaches, however, this improvement might come at the price of more false negatives for highly connected genes. Consequently, we develop a suite called DADA, which includes different uniform prioritization methods that effectively integrate existing approaches with the proposed statistical adjustment strategies. Comprehensive experimental results on the Online Mendelian Inheritance in Man (OMIM) database show that DADA outperforms existing methods in prioritizing candidate disease genes. CONCLUSIONS: These results demonstrate the importance of employing accurate statistical models and associated adjustment methods in network-based disease gene prioritization, as well as other network-based functional inference applications. DADA is implemented in Matlab and is freely available at http://compbio.case.edu/dada/. Finding genes associated with a disease is an important issue in the biomedical area and many gene prioritization methods have been proposed for this goal. Among these, network-based approaches are recently proposed and outperformed functional annotation-based ones. Here, we introduce a novel Cytoscape plug-in, GPEC, to help identify putative genes likely to be associated with specific diseases or pathways. In the plug-in, gene prioritization is performed through a random walk with restart algorithm, a state-of-the art network-based method, along with a gene/protein relationship network. The plug-in also allows users efficiently collect biomedical evidence for highly ranked candidate genes. A set of known genes, candidate genes and a gene/protein relationship network can be provided in a flexible way. We present gene prioritization system (GPSy), a cross-species gene prioritization system that facilitates the arduous but critical task of prioritizing genes for follow-up functional analyses. GPSy's modular design with regard to species, data sets and scoring strategies enables users to formulate queries in a highly flexible manner. Currently, the system encompasses 20 topics related to conserved biological processes including male gamete development discussed in this article. The web server-based tool is freely available at http://gpsy.genouest.org. Despite considerable progress in understanding the molecular origins of hereditary human diseases, the molecular basis of several thousand genetic diseases still remains unknown. High-throughput phenotype studies are underway to systematically assess the phenotype outcome of targeted mutations in model organisms. Thus, comparing the similarity between experimentally identified phenotypes and the phenotypes associated with human diseases can be used to suggest causal genes underlying a disease. In this manuscript, we present a method for disease gene prioritization based on comparing phenotypes of mouse models with those of human diseases. For this purpose, either human disease phenotypes are "translated" into a mouse-based representation (using the Mammalian Phenotype Ontology), or mouse phenotypes are "translated" into a human-based representation (using the Human Phenotype Ontology). We apply a measure of semantic similarity and rank experimentally identified phenotypes in mice with respect to their phenotypic similarity to human diseases. Our method is evaluated on manually curated and experimentally verified gene-disease associations for human and for mouse. We evaluate our approach using a Receiver Operating Characteristic (ROC) analysis and obtain an area under the ROC curve of up to . Furthermore, we are able to confirm previous results that the Vax1 gene is involved in Septo-Optic Dysplasia and suggest Gdf6 and Marcks as further potential candidates. Our method significantly outperforms previous phenotype-based approaches of prioritizing gene-disease associations. To enable the adaption of our method to the analysis of other phenotype data, our software and prioritization results are freely available under a BSD licence at http://code.google.com/p/phenomeblast/wiki/CAMP. Furthermore, our method has been integrated in PhenomeNET and the results can be explored using the PhenomeBrowser at http://phenomebrowser.net. Microarray data analysis has been shown to provide an effective tool for studying cancer and genetic diseases. Although classical machine learning techniques have successfully been applied to find informative genes and to predict class labels for new samples, common restrictions of microarray analysis such as small sample sizes, a large attribute space and high noise levels still limit its scientific and clinical applications. Increasing the interpretability of prediction models while retaining a high accuracy would help to exploit the information content in microarray data more effectively. For this purpose, we evaluate our rule-based evolutionary machine learning systems, BioHEL and GAssist, on three public microarray cancer datasets, obtaining simple rule-based models for sample classification. A comparison with other benchmark microarray sample classifiers based on three diverse feature selection algorithms suggests that these evolutionary learning techniques can compete with state-of-the-art methods like support vector machines. The obtained models reach accuracies above 90% in two-level external cross-validation, with the added value of facilitating interpretation by using only combinations of simple if-then-else rules. As a further benefit, a literature mining analysis reveals that prioritizations of informative genes extracted from BioHEL's classification rule sets can outperform gene rankings obtained from a conventional ensemble feature selection in terms of the pointwise mutual information between relevant disease terms and the standardized names of top-ranked genes. Candidate gene identification is typically labour intensive, involving laboratory experiments required to corroborate or disprove any hypothesis for a nominated candidate gene being considered the causative gene. The traditional approach to reduce the number of candidate genes entails fine-mapping studies using markers and pedigrees. Gene prioritization establishes the ranking of candidate genes based on their relevance to the biological process of interest, from which the most promising genes can be selected for further analysis. To date, many computational methods have focused on the prediction of candidate genes by analysis of their inherent sequence characteristics and similarity with respect to known disease genes, as well as their functional annotation. In the last decade, several computational tools for prioritizing candidate genes have been proposed. A large number of them are web-based tools, while others are standalone applications that install and run locally. This review attempts to take a close look at gene prioritization criteria, as well as candidate gene prioritization algorithms, and thus provide a comprehensive synopsis of the subject matter. Complex genetic disorders often involve products of multiple genes acting cooperatively. Hence, the pathophenotype is the outcome of the perturbations in the underlying pathways, where gene products cooperate through various mechanisms such as protein-protein interactions. Pinpointing the decisive elements of such disease pathways is still challenging. Over the last years, computational approaches exploiting interaction network topology have been successfully applied to prioritize individual genes involved in diseases. Although linkage intervals provide a list of disease-gene candidates, recent genome-wide studies demonstrate that genes not associated with any known linkage interval may also contribute to the disease phenotype. Network based prioritization methods help highlighting such associations. Still, there is a need for robust methods that capture the interplay among disease-associated genes mediated by the topology of the network. Here, we propose a genome-wide network-based prioritization framework named GUILD. This framework implements four network-based disease-gene prioritization algorithms. We analyze the performance of these algorithms in dozens of disease phenotypes. The algorithms in GUILD are compared to state-of-the-art network topology based algorithms for prioritization of genes. As a proof of principle, we investigate top-ranking genes in Alzheimer's disease (AD), diabetes and AIDS using disease-gene associations from various sources. We show that GUILD is able to significantly highlight disease-gene associations that are not used a priori. Our findings suggest that GUILD helps to identify genes implicated in the pathology of human disorders independent of the loci associated with the disorders. Disease-causing aberrations in the normal function of a gene define that gene as a disease gene. Proving a causal link between a gene and a disease experimentally is expensive and time-consuming. Comprehensive prioritization of candidate genes prior to experimental testing drastically reduces the associated costs. Computational gene prioritization is based on various pieces of correlative evidence that associate each gene with the given disease and suggest possible causal links. A fair amount of this evidence comes from high-throughput experimentation. Thus, well-developed methods are necessary to reliably deal with the quantity of information at hand. Existing gene prioritization techniques already significantly improve the outcomes of targeted experimental studies. Faster and more reliable techniques that account for novel data types are necessary for the development of new diagnostics, treatments, and cure for many diseases. Text mining methods can facilitate the generation of biomedical hypotheses by suggesting novel associations between diseases and genes. Previously, we developed a rare-term model called RaJoLink (Petric et al, J. Biomed. Inform. 42(2): 219-227, 2009) in which hypotheses are formulated on the basis of terms rarely associated with a target domain. Since many current medical hypotheses are formulated in terms of molecular entities and molecular mechanisms, here we extend the methodology to proteins and genes, using a standardized vocabulary as well as a gene/protein network model. The proposed enhanced RaJoLink rare-term model combines text mining and gene prioritization approaches. Its utility is illustrated by finding known as well as potential gene-disease associations in ovarian cancer using MEDLINE abstracts and the STRING database. BACKGROUND: Candidate gene prioritization aims to identify promising new genes associated with a disease or a biological process from a larger set of candidate genes. In recent years, network-based methods - which utilize a knowledge network derived from biological knowledge - have been utilized for gene prioritization. Biological knowledge can be encoded either through the network's links or nodes. Current network-based methods can only encode knowledge through links. This paper describes a new network-based method that can encode knowledge in links as well as in nodes. RESULTS: We developed a new network inference algorithm called the Knowledge Network Gene Prioritization (KNGP) algorithm which can incorporate both link and node knowledge. The performance of the KNGP algorithm was evaluated on both synthetic networks and on networks incorporating biological knowledge. The results showed that the combination of link knowledge and node knowledge provided a significant benefit across 19 experimental diseases over using link knowledge alone or node knowledge alone. CONCLUSIONS: The KNGP algorithm provides an advance over current network-based algorithms, because the algorithm can encode both link and node knowledge. We hope the algorithm will aid researchers with gene prioritization.

Which is the most common disease attributed to malfunction or absence of primary cilia?

When ciliary function is perturbed, photoreceptors may die, kidney tubules develop cysts, limb digits multiply and brains form improperly. Mice display abnormalities very similar to those of patients with neonatal diabetes and hypothyroidism syndrome, including the development of diabetes and polycystic kidney disease. Malformation of primary cilia, and in the collecting ducts of kidney tubules this is accompanied by development of autosomal recessive polycystic kidney disease (PKD).

Recent evidence suggests that structural and functional abnormalities of primary cilia in kidney epithelia are associated with mouse and human autosomal domit polycystic kidney disease. To determine whether fibrocystin/polyductin/tigmin (FPC), the protein product encoded by the PKHD1 gene that is responsible for autosomal recessive polycystic kidney disease among human subjects, is also a component of primary cilia in the kidney, antipeptide antibodies to the carboxyl-terminal intracellular domain and amino-terminal extracellular domain of FPC were generated and were characterized with immunoblotting and immuno-light and -electron microscopy. Immunolocalization in normal kidney tissue sections and cultured kidney cells demonstrated that FPC was localized to the primary cilia and concentrated on the basal bodies in both kidney tissue sections and cultured kidney cells. The FPC expression pattern was not altered in kidney cells with Pkd1 mutations. These findings suggest that FPC is a functional and/or structural component of primary cilia in kidney tubular cells. It is proposed that the pathogenesis of autosomal recessive polycystic kidney disease is linked to the dysfunction of primary cilia. Mutations of the polycystic kidney and hepatic disease 1 (PKHD1) gene have been shown to cause autosomal recessive polycystic kidney disease (ARPKD), but the cellular functions of the gene product (PKHD1) remain uncharacterized. To illuminate its properties, the spatial and temporal expression patterns of PKHD1 were determined in mouse, rat, and human tissues by using polyclonal Abs and mAbs recognizing various specific regions of the gene product. During embryogenesis, PKHD1 is widely expressed in epithelial derivatives, including neural tubules, gut, pulmonary bronchi, and hepatic cells. In the kidneys of the pck rats, the rat model of which is genetically homologous to human ARPKD, the level of PKHD1 was significantly reduced but not completely absent. In cultured renal cells, the PKHD1 gene product colocalized with polycystin-2, the gene product of autosomal domit polycystic disease type 2, at the basal bodies of primary cilia. Immunoreactive PKHD1 localized predomitly at the apical domain of polarized epithelial cells, suggesting it may be involved in the tubulogenesis and/or maintece of duct-lumen architecture. Reduced PKHD1 levels in pck rat kidneys and its colocalization with polycystins may underlie the pathogenic basis for cystogenesis in polycystic kidney diseases. Polycystic kidney disease (PKD) includes a group of disorders that are characterized by the presence of cysts in the kidney and other organs, including the pancreas. Here we show that in orpk mice, a model system for PKD that harbors a mutation in the gene that encodes the polaris protein, pancreatic defects start to occur at the end of gestation, with an initial expansion of the developing pancreatic ducts. Ductal dilation continues rapidly after birth and results in the formation of large, interconnected cysts. Expansion of pancreatic ducts is accompanied by apoptosis of neighboring acinar cells, whereas endocrine cell differentiation and islet formation appears to be unaffected. Polaris has been shown to co-localize with primary cilia, and these structures have been implicated in the formation of renal cysts. In the orpk pancreas, cilia numbers are reduced and cilia length is decreased. Expression of polycystin-2, a protein involved in PKD, is mislocalized in orpk mice. Furthermore, the cellular localization of beta-catenin, a protein involved in cell adhesion and Wnt signaling, is altered. Thus, polaris and primary cilia function are required for the maturation and maintece of proper tissue organization in the pancreas. The epithelial cells lining intrahepatic bile ducts (i.e., cholangiocytes), like many cell types in the body, have primary cilia extending from the apical plasma membrane into the bile ductal lumen. Cholangiocyte cilia express proteins such as polycystin-1, polycystin-2, fibrocystin, TRPV4, P2Y12, AC6, that account for ciliary mechano-, osmo-, and chemo-sensory functions; when these processes are disturbed by mutations in genes encoding ciliary-associated proteins, liver diseases (i.e., cholangiociliopathies) result. The cholangiociliopathies include but are not limited to cystic and fibrotic liver diseases associated with mutations in genes encoding polycystin-1, polycystin-2, and fibrocystin. In this review, we discuss the functions of cholangiocyte primary cilia, their role in the cholangiociliopathies, and potential therapeutic approaches. Primary cilia are nonmotile organelles implicated in signaling and sensory functions. Understanding how primary cilia assemble could shed light on the many human diseases caused by mutations in ciliary proteins. The centrosomal protein CP110 is known to suppress ciliogenesis through an unknown mechanism. Here, we report that CP110 interacts with CEP290--a protein whose deficiency is implicated in human ciliary disease--in a discrete complex separable from other CP110 complexes involved in regulating the centrosome cycle. Ablation of CEP290 prevents ciliogenesis without affecting centrosome function or cell-cycle progression. Interaction with CEP290 is absolutely required for the ability of CP110 to suppress primary cilia formation. Furthermore, CEP290 and CP110 interact with Rab8a, a small GTPase required for cilia assembly. Depletion of CEP290 interferes with localization of Rab8a to centrosomes and cilia. Our results suggest that CEP290 cooperates with Rab8a to promote ciliogenesis and that this function is antagonized by CP110. Primary (nonmotile) cilia are currently enjoying a renaissance in light of novel ascribed functions ranging from mechanosensory to signal transduction. Their importance for key developmental pathways such as Sonic Hedgehog (Shh) and Wnt is beginning to emerge. The function of nodal cilia, for example, is vital for breaking early embryonic symmetry, Shh signaling is important for tissue morphogenesis and successful Wnt signaling for organ growth and differentiation. When ciliary function is perturbed, photoreceptors may die, kidney tubules develop cysts, limb digits multiply and brains form improperly. The etiology of several uncommon disorders has recently been associated with cilia dysfunction. The causative genes are often similar and their cognate proteins certainly share cellular locations and/or pathways. Animal models of ciliary gene ablation such as Ift88, Kif3a, and Bbs have been invaluable for understanding the broad function of the cilium. Herein, we describe the wealth of information derived from the study of the ciliopathies and their animal models. In this study, we describe the generation and partial characterization of Krüppel-like zinc finger protein Glis3 mutant (Glis3(zf/zf)) mice. These mice display abnormalities very similar to those of patients with neonatal diabetes and hypothyroidism syndrome, including the development of diabetes and polycystic kidney disease. We demonstrate that Glis3 localizes to the primary cilium, suggesting that Glis3 is part of a cilium-associated signaling pathway. Although Glis3(zf/zf) mice form normal primary cilia, renal cysts contain relatively fewer cells with a primary cilium. We further show that Glis3 interacts with the transcriptional modulator Wwtr1/TAZ, which itself has been implicated in glomerulocystic kidney disease. Wwtr1 recognizes a P/LPXY motif in the C terminus of Glis3 and enhances Glis3-mediated transcriptional activation, indicating that Wwtr1 functions as a coactivator of Glis3. Mutations in the P/LPXY motif abrogate the interaction with Wwtr1 and the transcriptional activity of Glis3, indicating that this motif is part of the transcription activation domain of Glis3. Our study demonstrates that dysfunction of Glis3 leads to the development of cystic renal disease, suggesting that Glis3 plays a critical role in maintaining normal renal functions. We propose that localization to the primary cilium and interaction with Wwtr1 are key elements of the Glis3 signaling pathway. Although first described as early as 1898 and long considered a vestigial organelle of little functional importance, the primary cilium has become one of the hottest research topics in modern cell biology and physiology. Primary cilia are nonmotile sensory organelles present in a single copy on the surface of most growth-arrested or differentiated mammalian cells, and defects in their assembly or function are tightly coupled to many developmental defects, diseases and disorders. In normal tissues, the primary cilium coordinates a series of signal transduction pathways, including Hedgehog, Wnt, PDGFRalpha and integrin signaling. In the kidney, the primary cilium may function as a mechano-, chemo- and osmosensing unit that probes the extracellular environment and transmits signals to the cell via, e.g., polycystins, which depend on ciliary localization for appropriate function. Indeed, hypomorphic mutations in the mouse ift88 (previously called Tg737) gene, which encodes a ciliogenic intraflagellar transport protein, result in malformation of primary cilia, and in the collecting ducts of kidney tubules this is accompanied by development of autosomal recessive polycystic kidney disease (PKD). While PKD was one of the first diseases to be linked to dysfunctional primary cilia, defects in this organelle have subsequently been associated with many other phenotypes, including cancer, obesity, diabetes as well as a number of developmental defects. Collectively, these disorders of the cilium are now referred to as the ciliopathies. In this review, we provide a brief overview of the structure and function of primary cilia and some of their roles in coordinating signal transduction pathways in mammalian development, health and disease. Autosomal domit polycystic kidney disease (ADPKD), an inherited disease, leads to cyst formation in the kidneys. In this condition, the kidneys are grossly enlarged with multiple cysts that result in kidney failure in a majority of individuals. This condition is also associated with cysts in other organs. Recent research has focused on defects in signaling mediated by the primary cilia as the causative factor in ADPKD. Primary cilia are also present in odontogenic epithelium. Dentigerous cyst also is a developmental cyst whose pathogenesis is controversial. Recent studies have shown that loss of Ptch and Shh signaling pathways are involved in the cystogenesis of dentigerous cyst. The Shh signaling pathway is active in the primary cilia. A scanning electron microscopic study of a dentigerous cyst wall in an ADPKD patient showed structures similar to primary cilia. Based on the presentation of a dentigerous cyst in an autosomal domit polycystic kidney patient and the demonstration of primary cilia like structures on the cyst wall by using a scanning electron microscope, a new hypothesis for the pathogenesis of dentigerous cyst is proposed. The pathophysiological mechanisms underlying the onset and inexorable progression of the late‑onset form of Alzheimer's disease (AD) are still the object of controversy. This review takes stock of some most recent advancements of this field concerning the complex roles played by the amyloid‑β (Aβ)‑binding p75 neurotrophin receptor (p75NTR) and calcium‑sensing receptor (CaSR) and by the primary cilia in AD. Apart from their physiological roles, p75NTR is more intensely expressed in the hippocampus of human AD brains and Aβ‑bound p75NTR triggers cell death, whereas Aβ‑bound CaSR signalling induces the de novo synthesis and release of nitric oxide (NO), vascular endothelial growth factor (VEGF)‑A and Aβ peptides (Aβs), particularly on the part of normal adult human astrocytes. The latter effect could significantly increase the pool of Aβ‑ and NO‑producing nerve cells favouring the progressive spread of a self‑sustaining and self‑reinforcing 'infectious' mechanism of neural and vascular (i.e. blood-brain barrier) cell damage. Interestingly, primary cilia concentrate p75NTR receptors in their membranes and are abnormally structured/damaged in transgenic (Tg) AD‑model mice, which could impact on the adult neurogenesis occurring in the dentate gyrus's subgranular zone (SGZ) that is necessary for new memory encoding, thereby favouring typical AD cognitive decline. Altogether, these findings may pave the way to novel therapeutic approaches to AD, particularly in its mild cognitive impairment (MCI) and pre‑MCI stages of development.

What is the usefulness of ultraconserved elements in phylogeny?

Because orthologous UCEs can be obtained from a wide array of taxa, are polymorphic at shallow evolutionary timescales, and can be generated rapidly at low cost, they are an effective genetic marker for studies investigating evolutionary patterns and processes at shallow timescales

Phylogenomics offers the potential to fully resolve the Tree of Life, but increasing genomic coverage also reveals conflicting evolutionary histories among genes, demanding new analytical strategies for elucidating a single history of life. Here, we outline a phylogenomic approach using a novel class of phylogenetic markers derived from ultraconserved elements and flanking DNA. Using species-tree analysis that accounts for discord among hundreds of independent loci, we show that this class of marker is useful for recovering deep-level phylogeny in placental mammals. In broad outline, our phylogeny agrees with recent phylogenomic studies of mammals, including several formerly controversial relationships. Our results also inform two outstanding questions in placental mammal phylogeny involving rapid speciation, where species-tree methods are particularly needed. Contrary to most phylogenomic studies, our study supports a first-diverging placental mammal lineage that includes elephants and tenrecs (Afrotheria). The level of conflict among gene histories is consistent with this basal divergence occurring in or near a phylogenetic "anomaly zone" where a failure to account for coalescent stochasticity will mislead phylogenetic inference. Addressing a long-standing phylogenetic mystery, we find some support from a high genomic coverage data set for a traditional placement of bats (Chiroptera) sister to a clade containing Perissodactyla, Cetartiodactyla, and Carnivora, and not nested within the latter clade, as has been suggested recently, although other results were conflicting. One of the most remarkable findings of our study is that ultraconserved elements and their flanking DNA are a rich source of phylogenetic information with strong potential for application across Amniotes. Although massively parallel sequencing has facilitated large-scale DNA sequencing, comparisons among distantly related species rely upon small portions of the genome that are easily aligned. Methods are needed to efficiently obtain comparable DNA fragments prior to massively parallel sequencing, particularly for biologists working with non-model organisms. We introduce a new class of molecular marker, anchored by ultraconserved genomic elements (UCEs), that universally enable target enrichment and sequencing of thousands of orthologous loci across species separated by hundreds of millions of years of evolution. Our analyses here focus on use of UCE markers in Amniota because UCEs and phylogenetic relationships are well-known in some amniotes. We perform an in silico experiment to demonstrate that sequence flanking 2030 UCEs contains information sufficient to enable unambiguous recovery of the established primate phylogeny. We extend this experiment by performing an in vitro enrichment of 2386 UCE-anchored loci from nine, non-model avian species. We then use alignments of 854 of these loci to unambiguously recover the established evolutionary relationships within and among three ancient bird lineages. Because many organismal lineages have UCEs, this type of genetic marker and the analytical framework we outline can be applied across the tree of life, potentially reshaping our understanding of phylogeny at many taxonomic levels. We present the first genomic-scale analysis addressing the phylogenetic position of turtles, using over 1000 loci from representatives of all major reptile lineages including tuatara. Previously, studies of morphological traits positioned turtles either at the base of the reptile tree or with lizards, snakes and tuatara (lepidosaurs), whereas molecular analyses typically allied turtles with crocodiles and birds (archosaurs). A recent analysis of shared microRNA families found that turtles are more closely related to lepidosaurs. To test this hypothesis with data from many single-copy nuclear loci dispersed throughout the genome, we used sequence capture, high-throughput sequencing and published genomes to obtain sequences from 1145 ultraconserved elements (UCEs) and their variable flanking DNA. The resulting phylogeny provides overwhelming support for the hypothesis that turtles evolved from a common ancestor of birds and crocodilians, rejecting the hypothesized relationship between turtles and lepidosaurs. Evolutionary relationships among birds in Neoaves, the clade comprising the vast majority of avian diversity, have vexed systematists due to the ancient, rapid radiation of numerous lineages. We applied a new phylogenomic approach to resolve relationships in Neoaves using target enrichment (sequence capture) and high-throughput sequencing of ultraconserved elements (UCEs) in avian genomes. We collected sequence data from UCE loci for 32 members of Neoaves and one outgroup (chicken) and analyzed data sets that differed in their amount of missing data. An alignment of 1,541 loci that allowed missing data was 87% complete and resulted in a highly resolved phylogeny with broad agreement between the Bayesian and maximum-likelihood (ML) trees. Although results from the 100% complete matrix of 416 UCE loci were similar, the Bayesian and ML trees differed to a greater extent in this analysis, suggesting that increasing from 416 to 1,541 loci led to increased stability and resolution of the tree. Novel results of our study include surprisingly close relationships between phenotypically divergent bird families, such as tropicbirds (Phaethontidae) and the sunbittern (Eurypygidae) as well as between bustards (Otididae) and turacos (Musophagidae). This phylogeny bolsters support for monophyletic waterbird and landbird clades and also strongly supports controversial results from previous studies, including the sister relationship between passerines and parrots and the non-monophyly of raptorial birds in the hawk and falcon families. Although significant challenges remain to fully resolving some of the deep relationships in Neoaves, especially among lineages outside the waterbirds and landbirds, this study suggests that increased data will yield an increasingly resolved avian phylogeny. Comparative genetic studies of non-model organisms are transforming rapidly due to major advances in sequencing technology. A limiting factor in these studies has been the identification and screening of orthologous loci across an evolutionarily distant set of taxa. Here, we evaluate the efficacy of genomic markers targeting ultraconserved DNA elements (UCEs) for analyses at shallow evolutionary timescales. Using sequence capture and massively parallel sequencing to generate UCE data for five co-distributed Neotropical rainforest bird species, we recovered 776-1516 UCE loci across the five species. Across species, 53-77% of the loci were polymorphic, containing between 2.0 and 3.2 variable sites per polymorphic locus, on average. We performed species tree construction, coalescent modeling, and species delimitation, and we found that the five co-distributed species exhibited discordant phylogeographic histories. We also found that species trees and divergence times estimated from UCEs were similar to the parameters obtained from mtDNA. The species that inhabit the understory had older divergence times across barriers, contained a higher number of cryptic species, and exhibited larger effective population sizes relative to the species inhabiting the canopy. Because orthologous UCEs can be obtained from a wide array of taxa, are polymorphic at shallow evolutionary timescales, and can be generated rapidly at low cost, they are an effective genetic marker for studies investigating evolutionary patterns and processes at shallow timescales.

Treprostinil is an analogue for which prostaglandin?

Treprostinil is a prostaglandin I(2) (PGI(2)) analog.

Primary pulmonary hypertension (PPH) is characterized by increased pulmonary arterial pressure and vascular resistance. We and others have observed that inflammatory cytokines and infiltrates are present in the lung tissue, but the significance is uncertain. Treprostinil (TRE), a prostacyclin analogue with extended half-life and chemical stability, has shown promise in the treatment of PPH. We hypothesize that TRE might exert beneficial effects in PPH by antagonizing inflammatory cytokine production in the lung. Here we show that TRE dose-dependently inhibits inflammatory cytokine (tumor necrosis factor-alpha, interleukin-1beta, interleukin-6, and granulocyte macrophage colony-stimulating factor) secretion and gene expression by human alveolar macrophages. TRE blocks NFkappaB activation, but IkappaB-alpha phosphorylation and degradation are unaffected. Moreover, TRE does not affect the formation of the NFkappaB.DNA complex but blocks nuclear translocation of p65. These results are the first to illustrate the anti-cytokine actions of TRE in down-regulating NFkappaB, not through its inhibitory component or by direct binding but by blocking nuclear translocation. These data indicate that inflammatory mechanisms may be important in the pathogenesis of PPH and cytokine antagonism by blocking NFkappaB may contribute to the efficacy of TRE therapy in PPH. We report a case of severe digital ulcerations associated with systemic sclerosis, successfully treated with treprostinil (Remodulin). There was improvement within days of the treatment initiation; complete healing was accomplished after 16 weeks of therapy. Patients with systemic sclerosis and peripheral small vessel disease have limited therapeutic options. Treprostinil is a prostacyclin analogue that can be delivered by subcutaneous infusion and is approved in the USA only for treatment of primary pulmonary hypertension. This report provides an impressive example of an alternative, complementary indication for the use of treprostinil. Pulmonary arterial hypertension (PAH) is characterized by abnormalities in endothelial and smooth muscle cell function. Prostacyclin released by endothelial cells is a potent vasodilator by increasing cyclic adenosine monophosphate. Sildenafil, an inhibitor of phosphodiesterase-5, increases cyclic guanosine monophosphate in the lungs, producing vasodilation. To test for a therapeutic benefit of the combination of a prostacyclin analogue, subcutaneous treprostinil, and sildenafil, a proof-of-concept, open-label investigational trial was initiated. Subjects with PAH in World Health Organization (WHO) functional classes II to IV receiving subcutaneous treprostinil for > or =6 months were evaluated with an exercise treadmill test using the Naughton-Balke protocol at baseline and after 12 weeks. Sildenafil 50 mg 3 times daily was added to the treprostinil. Mean treadmill times in seconds were compared before and after 12 weeks of therapy. Nine subjects enrolled in the trial; 7 were women (mean age 35 years). At baseline, 3 subjects were in WHO functional class II and 6 subjects were in WHO functional class III. The mean treadmill time at baseline was 465 +/- 167 seconds and at 12 weeks was 656 +/- 205 seconds (42% improvement, p = 0.049). All patients had symptomatic improvement. In conclusion, this pilot study of subcutaneous treprostinil with sildenafil for PAH suggests additive beneficial effects. Intravenous epoprostenol improves exercise capacity and survival in patients with pulmonary arterial hypertension (PAH); however, chemical instability and a short half-life have caused limitations in its use. The chemically stable prostacyclin analogue treprostinil has a longer half-life, and improves hemodynamics and signs/symptoms of PAH. This study investigated the feasibility of transitioning patients with PAH from intravenous epoprostenol to intravenous treprostinil using a rapid switch protocol. Twelve PAH patients were enrolled in a 12 week prospective open label study. Patients were switched from intravenous epoprostenol to intravenous treprostinil (1:1 ng/kg/min) by a direct switch of the medication reservoir from epoprostenol to treprostinil. The dose of treprostinil was adjusted throughout the study to achieve a 2-fold increase of treprostinil compared with the baseline epoprostenol dose. Rapid transition to treprostinil was achieved without serious adverse events and, baseline clinical status was maintained over 12 weeks. The mean baseline epoprostenol dose was 28 +/- 14 ng/kg/min. At week 12, the mean treprostinil dose was 62 +/- 30 ng/kg/min. All patients reported less prostacyclin-related side effects with treprostinil and remained on treprostinil after study completion. Selected patients with PAH can be safely transitioned from intravenous epoprostenol to intravenous treprostinil using a rapid switch protocol. INTRODUCTION: Pulmonary arterial hypertension (PAH) is a serious primary illness of the pulmonary arterioles, characterised by progressive precapillary pulmonary hypertension. The conventional therapy for this condition is so-called specific pharmacotherapy, which addresses the key mechanisms in the pathophysiology of the illness, making use of drugs from the prostanoid group, endothelin receptor antagonists and phosphodiesterase inhibitors. Treprostinil is a stable analogue of prostacyclin, which can be administered subcutaneously, intravenously or by inhalation. PATIENT SAMPLE AND METHOD: In the centre for pulmonary hypertension in the Second Internal Clinic of Cardiology and Angiology of 1st Faculty of Medicine, Charles University, and the General Teaching Hospital in Prague, 22 patients with PAH (idiopathic PAH, familial PAH, PAH associated with congenital heart disease and PAH associated with systemic connective tissue disease) were treated with trerpostinil, 18 patients with a continuous subcutaneous infusion and 4 patients with a continuous intravenous infusion. The indicators followed were the distance reached in a 6-minute walking test, functional capacity assessed by NYHA classification and mortality. RESULTS: The patients for whom treprostinil treatment was indicated had an average pressure in the right atrium of 11.9 +/- 4.2 mm Hg, average pressure in the pulmonary artery of 56.8 +/- 10.7 mm Hg, a cardiac index of 1.78 +/- 0.25 l/min/m2 and a total pulmonary resistance of 16.26 +/- 4.48 WU. 15 patients were functionally NYHA III and 7 patients were NYHA IV. The average distance achieved in a 6-minute walk test before the start of treatment was 326 +/- 83 m. When treated with gradually increasing doses of treprostinil the distance achieved in the 6-minute walk test improved. After 6 months, the group that received subcutaneous treatment had extended their distance to 359 m, after 12 months it was 393 m, after 24 months 447 m and after 36 months 494 m. After 6 months, the group that received intravenous treatment had extended their distance to 473 m, which increased to 451 m after 12 months and 489 m after 24 months. Functional capacity also improved. In total 5 patients were unable to tolerate the subcutaneous infusion, of whom 3 were placed on intravenous treprostinil and 2 on oral bosentan. 7 of the patients died in the period examined (31.8%). CONCLUSION: Treprostinil improves symptoms and hemodynamics for PAH patients and reduces mortality. Prostacyclin and its analogues (prostanoids) are potent vasodilators and possess antithrombotic, antiproliferative and anti-inflammatory properties. Pulmonary hypertension (PH) is associated with vasoconstriction, thrombosis and proliferation, and the lack of endogenous prostacyclin may considerably contribute to this condition. This supports a strong rationale for prostanoid use as therapy for this disease. The first experiences of prostanoid therapy in PH patients were published in 1980. Epoprostenol, a synthetic analogue of prostacyclin, and the chemically stable analogues iloprost, beraprost and treprostinil were tested in randomised controlled trials. The biological actions are mainly mediated by activation of specific receptors of the target cells; however, new data suggest effects on additional intracellular pathways. In the USA and some European countries, intravenous infusion of epoprostenol and treprostinil, as well as subcutaneous infusion of treprostinil and inhalation of iloprost, have been approved for therapy of pulmonary arterial hypertension. Iloprost infusion and beraprost tablets have been approved in few other countries. Ongoing clinical studies investigate oral treprostinil, inhaled treprostinil and the combination of inhaled iloprost and sildenafil in pulmonary arterial hypertension. Combination of other targeted therapies with prostanoids appears to be effective and safe. After 25 yrs of continued knowledge, prostanoids remain a mainstay in the treatment of pulmonary arterial hypertension. Chemokines for neutrophils such as growth-related oncogene-alpha (GRO-alpha) are important in patients with refractory or severe asthma. Prostaglandin I(2) (PGI(2)) analogues were regarded as potential treatments for asthma. Dendritic cells (DCs) are the professional antigen-presenting cells and play a critical role in regulating immune response. However, it is unknown whether PGI(2) analogues have regulatory effects on GRO-alpha expression in human monocyte-derived DCs (MDDCs). The human MDDCs were pretreated with iloprost and treprostinil (two PGI(2) analogues) or forskolin, a cyclic adenosine monophosphate (cAMP) activator, before stimulation with lipopolysaccharide (LPS). In some cases, I prostanoid (IP) receptor and E prostanoid (EP) antagonists were pretreated before PGI(2) analogue treatment. To investigate the intracellular signaling, nuclear factor (NF)-kappaB inhibitor and the mitogen-activated protein kinase (MAPK) inhibitors were pretreated before PGI(2) analogue treatment. GRO-alpha was measured by enzyme-linked immunosorbent assay. Intracellular signaling was also investigated by Western blot. Iloprost and treprostinil enhanced LPS-induced GRO-alpha expression in MDDCs. This effect could be reversed by an I prostanoid receptor antagonist, CAY10449, but not EP receptor antagonists. Forskolin conferred a similar modulating effect as that noted in iloprost- and treprostinil-treated MDDCs. PGI(2) analogue-enhanced LPS-induced GRO-alpha expression was reduced by MAPK-p38 inhibitor, SB203580. PGI(2) analogues enhanced LPS-induced phospho-p38 expression. PGI(2) analogues enhanced LPS-induced GRO-alpha expression via the IP receptor-cAMP and p38-MAPK pathways in human MDDCs, which may further recruit neutrophil accumulation and adversely affect patients with refractory or severe asthma because of airway neutrophilia. These effects should be considered for PGI(2) analogues as candidates for the treatment of asthma. Prostanoid IP receptors coupled to Gs are thought to be the primary target for prostacyclin (PGI(2)) analogues. However, these agents also activate prostanoid EP(1-4) receptor subtypes to varying degrees, which are positively (EP(2/4)) or negatively (EP(3)) coupled to adenylate cyclase through Gs or Gi, respectively. We investigated the role of these receptors in modulating relaxation to PGI(2) analogues cicaprost, iloprost and treprostinil in pre-contracted segments of rat tail artery. Prostanoid IP (RO1138452), EP(4) (GW627368X), EP(3) (L-798106), EP(1-3) (AH6809), and EP(1) (SC-51322) receptor antagonists were used to determine each receptor contribution. The role of G(i/o) was investigated using pertussis toxin (PTX), while dependence on cAMP was determined using adenylate cyclase (2'5'dideoxyadenosine, DDA) and protein kinase A (2'-O-monobutyryladenosine- 3',5'-cyclic monophosphorothioate, Rp- isomer, Rp-2'-O-MB-cAMPS) inhibitors, and by measurement of tissue cAMP. All analogues caused relaxation which was significantly (P<0.01) inhibited by RO1138452; with maximum response to cicaprost, iloprost and treprostinil reduced by 51%, 66% and 37%, respectively. GW627368X had no effect when used alone, but in combination with RO1138452, caused a rightward shift of the curves for cicaprost and iloprost but not treprostinil. PTX treatment potentiated relaxation to all 3 analogues (P<0.01), as did L798106 and AH6809 but not SC-51322. Basal cAMP levels were higher in PTX-treated tissues and DDA- and Rp-2'-O-MB-cAMPs--sensitive responses increased to analogue concentrations <0.1μM. In conclusion, prostanoid EP(3) receptors via G(i/o) negatively modulate prostanoid IP receptor-mediated relaxation to cicaprost, iloprost and treprostinil. However, other pathways contribute to analogue-induced vasorelaxation, the nature of which remains unclear for treprostinil. Fibrocytes comprise a recently described cell type of blood-derived, fibroblast-like cells that are recruited from the circulation to sites of wound repair, vascular remodeling, or fibrotic tissue remodeling. We recently showed that the stable prostacyclin analogue treprostinil, a clinically approved drug for pulmonary arterial hypertension (PAH), significantly reduced the recruitment of fibrocytes to sites of vascular remodeling in experimental hypoxic pulmonary hypertension. Here we report on the molecular mechanism underlying the inhibitory action of treprostinil on the adhesion and differentiation of human fibrocytes. Human fibrocytes expressed the prostanoid receptors, prostaglandin I (IP) receptors and prostaglandin E subtype receptors (EP2 and EP4). The generation of intracellular cyclic adenosine monophosphate (cAMP) by treprostinil reduced the expression of the integrins CD49 and CD29 when freshly isolated human peripheral blood mononuclear cells were treated with treprostinil. Cell-matrix adhesion was significantly impaired by treatment with treprostinil. We present evidence for a treprostinil/cAMP-induced downstream suppression of extracellular regulated kinase (ERK) that is transmitted via a protein kinase A-independent pathway through Rap proteins, which sequester Ras. The resulting dephosphorylated state of c-Raf limits the activity of ERK. The cell-matrix adhesion assay with the ERK inhibitor further confirmed that the adhesion of fibrocytes was impaired. Thus our data suggest that treprostinil inhibits the adhesion and differentiation of fibrocytes by limiting the activity of ERK via the cAMP-Rap axis. OBJECTIVE AND DESIGN: Although treatment for asthma control has improved a lot recently, refractory asthma is still a challenge for clinicians. Evidence revealed that anti-tumor necrosis factor (TNF)-α therapy may have potential in treating refractory asthma. Recently in an animal model, prostaglandin I(2) (PGI(2)) analogues can suppress the cardinal feature of asthma. However, whether PGI(2) analogues can regulate TNF-α expression in monocytes and the mechanism is not well-known. MATERIALS AND METHODS: The human monocytes were pretreated with beraprost, iloprost and treprostinil, three PGI(2) analogues, before stimulation with lipopolysaccharide (LPS). TNF-α concentration of the cell supernatants was measured by ELISA. Intracellular signaling was investigated by Western blot. RESULTS: PGI(2) analogues suppressed LPS-induced TNF-α expression in THP-1 cells. CAY10449, an I prostanoid receptor antagonist, could reverse these effects. Beraprost increased intracellular cAMP level in THP1 cells. Forskolin, an adenylyl cyclase activator, could confer similar effect. LPS-induced TNF-α expression in THP-1 cells could be reversed by mitogen-activator protein kinase (MAPK)-p38, extracellular signal-related kinase (ERK) and c-Jun N-terminal kinase (JNK) inhibitors. Western blot revealed that beraprost suppressed MAPK phospho-p38, phosphor-JNK and phosphor-ERK expression. CONCLUSION: PGI(2) analogues suppressed LPS-induced TNF-α expression in THP-1 cells via the IP receptor-cAMP and the MAPK pathways. PGI(2) analogues may have potentiality to treat asthma. Prostaglandin I(2) (PGI(2)) analog is regarded as a potential candidate for treating asthma. Human myeloid dendritic cells (mDCs) play a critical role in the pathogenesis of asthma. However, the effects of PGI(2) analog on human mDCs are unknown. In the present study, circulating mDCs were isolated from six healthy subjects. The effects of PGI(2) analogs iloprost and treprostinil on cytokine production, maturation and T-cell stimulatory function of human mDCs were investigated. Tumor necrosis factor (TNF)-α and interleukin (IL)-10 were measured by enzyme-linked immunosorbent assay. The expression of costimulatory molecules was investigated by flow cytometry. T-cell stimulatory function was investigated by measuring interferon (IFN)-γ, IL-13 and IL-10 production by T cells cocultured with iloprost-treated mDCs. Intracellular signaling was investigated by Western blot and chromatin immunoprecipitation. We found that iloprost and treprostinil induced IL-10, but suppressed TNF-α production in polyinosinic-polycytidylic acid (poly I:C)-stimulated mDCs. This effect was reversed by the I-prostanoid (IP), E-prostanoid (EP) receptor antagonists or intracellular free calcium (Ca(2+)) chelator. Forskolin, an adenyl cyclase activator, conferred a similar effect. Iloprost and treprostinil increased intracellular adenosine 3',5'-cyclic monophosphate (cAMP) levels, and iloprost also increased intracellular Ca(2+). Iloprost suppressed poly I:C-induced mitogen-activated protein kinase (MAPK) phospho-p38 and phospho-activating transcription factor (ATF)2 expression. Iloprost downregulated poly I:C-induced histone H3K4 trimethylation in the TNFA gene promoter region via suppressing translocation of histone 3 lysine 4 (H3K4)-specific methyltransferases MLL (mixed lineage leukemia) and WDR5 (WD repeat domain 5). Iloprost-treated mDCs inhibited IL-13, IFN-γ and IL-10 production by T cells. In conclusion, PGI(2) analogs enhance IL-10 and suppress TNF-α expression through the IP/EP2/EP4 receptors-cAMP and EP1 receptor-Ca(2+) pathway. Iloprost suppressed TNF-α expression via the MAPK-p38-ATF2 pathway and epigenetic regulation by downregulation of histone H3K4 trimethylation. The prostacyclin analogues, iloprost and treprostinil are extensively used in treating pulmonary hypertension. Their binding profile and corresponding biochemical cellular responses on human prostanoid receptors expressed in cell lines, have now been compared. Iloprost had high binding affinity for EP1 and IP receptors (Ki 1.1 and 3.9 nM, respectively), low affinity for FP, EP3 or EP4 receptors, and very low affinity for EP2, DP1 or TP receptors. By contrast, treprostinil had high affinity for the DP1, EP2 and IP receptors (Ki 4.4, 3.6 and 32 nM, respectively), low affinity for EP1 and EP4 receptors and even lower affinity for EP3, FP and TP receptors. In functional assays, iloprost had similar high activity in elevating cyclic AMP levels in cells expressing the human IP receptor and stimulating calcium influx in cells expressing EP1 receptors (EC50 0.37 and 0.3 nM, respectively) with the rank order of activity on the other receptors comparable to the binding assays. As with binding studies, treprostinil elevated cyclic AMP with a similar high potency in cells expressing DP1, IP and EP2 receptors (EC50 0.6, 1.9 and 6.2 nM, respectively), but had low activity at the other receptors. Activation of IP, DP1 and EP2 receptors, as with treprostinil, can all result in vasodilatation of human pulmonary arteries. However, activation of EP1 receptors can provoke vasoconstriction, and hence may offset the IP-receptor mediated vasodilator effects of iloprost. Treprostinil may therefore differ from iloprost in its overall beneficial pulmonary vasorelaxant profile and other pharmacological actions, especially in diseases where the IP receptor is down-regulated. OBJECTIVE: Among pleiotropic effects, the capacity of prostaglandin I(2) (PGI(2)) analogues to affect adaptive immunity remains poorly characterised. The purpose of this study was to assess whether PGI(2) analogues could affect T helper (Th) cell responses in patients with systemic sclerosis (SSc) and healthy donors (HD). METHODS: Peripheral blood mononuclear cells (PBMC) were obtained from 33 patients with SSc and 29 HD. Cytokine levels in PBMC and monocyte/CD4 T cell cultures were quantified by immunoassays. The frequencies of interleukin (IL)-17A, IL-22, interferon γ (IFNγ) and IL-4-producing CD4 T cells were assessed by multiparametric flow cytometry. Selective receptor antagonists, cytokine blocking antibodies and signalling protein inhibitors were used to identify the receptors and signalling pathways mediating PGI(2) analogue effects. RESULTS: Th17 and Th22 cells were more abundant in individuals with SSc than in HD. PGI(2) analogues (iloprost, treprostinil and beraprost) significantly increased IL-17A and IL-22 in vitro while decreasing IFNγ production both in SSc and HD PBMC. These effects relied on the specific expansion of Th17 and Th22 and inhibition of Th1 cells. The enhanced Th17 cell responses depended on increased IL-23 production by monocytes, involved the IP prostacyclin receptor and required protein kinase A activation. Importantly, in vivo administration of iloprost in individuals with SSc presenting with digital ulcers resulted in a significant increase in the frequency of Th17 cells. CONCLUSIONS: These findings demonstrate that PGI(2) analogues affect Th cell differentiation/expansion programmes, favouring Th17 and inhibiting Th1 cell responses in SSc. The impact of these changes on the disease course needs to be taken into consideration and further exploited to improve SSc. Treprostinil is a synthetic prostacyclin analogue with antiplatelet and vasodilatory properties. It is the only prostacyclin analogue with different options of delivery, i.e. subcutaneous, intravenous, inhaled or oral. Subcutaneous treprostinil has been shown in short- and long-term studies to improve exercise capacity, functional class, haemodynamics and survival in patients with pulmonary arterial hypertension (PAH). Pain at the infusion site has been a major drawback of subcutaneous treprostinil, hampering dose titration, and ultimately leading to increased discontinuation rates. The additional clinical interest in treprostinil as an alternative intravenous prostacyclin has developed due to its favourable properties, including longer half-life, chemical stability, the possibility of intravenous infusion without the need for ice packs, and easy drug preparation. Intravenous treprostinil improves exercise capacity, functional class and haemodynamics in patients with PAH, over the period of 12 weeks. If patients are switched to intravenous treprostinil, they usually need to double the dose to attain the same efficacy. Whether the effect of intravenous treprostinil remains clinically relevant beyond 12 weeks is not known, and a longer follow-up would be required to investigate this. Inhaled treprostinil is an efficacious treatment in PAH patients who are moderately symptomatic on background oral therapy. Oral treprostinil on top of background therapy did not lead to an improvement in 6-minute walking distance after 16 weeks of treatment. INTRODUCTION: Treprostinil diethanolamine is an innovative salt form of the prostacyclin analogue, treprostinil sodium, developed as an oral sustained release (SR) osmotic tablet. The availability of a formulation permitting convenient systemic delivery might have applicability to scleroderma vascular complications. We evaluated pharmacokinetics and perfusion in scleroderma patients with digital ischemia following escalating twice-daily doses of treprostinil diethanolamine SR. METHODS: Scleroderma patients with digital ulcers were enrolled in this dual-center, open-label, phase I pharmacokinetic study. Drug concentrations and perfusion, quantified by laser Doppler imaging, were measured over 12 hours at the 2 mg and 4 mg (or maximally tolerated) doses. Pharmacokinetic parameters were determined from individual plasma concentration versus time profiles using non-compartmental analysis methods. Digital perfusion and skin temperature were modeled as a function of log-transformed drug concentration and other covariates by performing repeated measures analyses using random effects models. RESULTS: Nineteen scleroderma patients (84% female, 53% limited scleroderma) received treprostinil diethanolamine SR with dose titration up to 4 mg twice daily as tolerated. Peak concentrations (mean maximum plasma concentration (Cmax) = 1,176 and 2,107 pg/mL) occurred approximately 3.6 hours after dose administration, and overall exposure (under the plasma concentration-time curve from time 0 to 12 hours post dose (AUC0-12) = 7,187 and 12,992 hr*pg/mL) was linear between the 2 mg and 4 mg doses. Perfusion and digital skin temperature were positively associated with log-transformed plasma concentration at the 4 mg dose (P = 0.015 and P = 0.013, respectively). The most frequent adverse events were similar to those seen with prostacyclin analogues. CONCLUSIONS: Oral treprostinil diethanolamine was effectively absorbed in patients with scleroderma. Drug administration was temporally associated with improved cutaneous perfusion and temperature. Treprostinil diethanolamine may provide a new therapeutic option for Raynaud's phenomenon and the peripheral vascular disease of scleroderma. TRIAL REGISTRATION: ClinicalTrials.gov NCT00848939. The prostacyclin (IP) receptor agonists, treprostinil, iloprost and the selexipag metabolite, MRE-269 (ACT-333679) were evaluated in rat distal pulmonary blood vessels. Small pulmonary arteries and veins were pre-contracted with the thromboxane mimetic, U46619 (25 and 100nM, respectively), and relaxation determined with and without IP receptor antagonists, RO1138452 and RO3244794. In arteries, treprostinil was a more potent vasorelaxant than iloprost, while the efficacy of iloprost was greater. In pulmonary arteries, treprostinil-induced relaxation was essentially abolished by both IP antagonists (1μM), while responses to iloprost were partially inhibited. Both treprostinil and iloprost were equipotent, prominently relaxing pulmonary veins with responses being similarly and partially sensitive to IP antagonists. In contrast, RO1138452 failed to inhibit relaxations to MRE-269 in either pulmonary arteries or veins, suggesting no involvement of typical IP receptors. Thus, rat pulmonary tissues cannot be considered appropriate to assess classical IP receptors using the proposed highly selective non-prostanoid agonist MRE-269, contrasting with the IP receptor agonism profile of prostacyclin analogues, iloprost and treprostinil. WHAT IS KNOWN: Treprostinil diolamine (oral treprostinil) is a prostacyclin analogue currently being evaluated for the treatment of pulmonary arterial hypertension as a sustained-release (SR) oral tablet. Previous data have demonstrated that the oral bioavailability of treprostinil was improved when taken with a meal containing at least 500 calories. OBJECTIVE: As twice-daily intake of a high-fat, high-calorie meal may be undesirable or not feasible for some patients, this open-label, randomized, crossover study evaluated the effect of different meal compositions [a 500-calorie well-balanced meal (WB500), a 250-calorie well-balanced meal (WB250), a 250-calorie high-fat meal (HF250) and a 250-calorie well-balanced liquid meal (Ensure®)] on the relative bioavailability of oral treprostinil. METHODS: Thirty-two healthy volunteers were administered a single 1-mg SR tablet of oral treprostinil immediately following each study meal. Each dose of oral treprostinil was separated by a 7-day washout period. Serial plasma samples were obtained over a 36-h postdose. Safety was assessed in all patients who received study drug. RESULTS AND DISCUSSION: Treprostinil plasma exposure (Cmax and AUC0-inf) decreased only slightly, 5-15% with decreasing caloric and increasing fat content. Headache was the most commonly reported prostacyclin-related adverse event (three reports). WHAT IS NEW AND CONCLUSION: Overall, there were no clinically significant differences in the relative bioavailability of oral treprostinil when administered immediately after meals containing 250-500 calories and 30-50% fat. These data support the administration of oral treprostinil with a meal containing as few as 250 calories and 30-50% fat, which is significant for ensuring patient convenience and compliance, particularly as consistency with regard to meals may impact oral treprostinil pharmacokinetics. WHAT IS KNOWN AND OBJECTIVE: Treprostinil diolamine (oral treprostinil) is a prostacyclin analogue under evaluation for the treatment for pulmonary arterial hypertension (PAH). This study assessed the pharmacokinetics (PK) and safety of treprostinil following oral administration of a single sustained-release 1 mg dose in subjects with hepatic impairment. METHODS: Four cohorts, including healthy volunteers, and subjects with mild, moderate and severe hepatic impairment were enrolled. Thirty subjects completed the study. Mean treprostinil clearance values (CL/F) decreased with the severity of hepatic impairment. The decrease in CL/F resulted in a marked increase in exposure levels of treprostinil. Relative to healthy subjects, mean area under the curve from time zero to 24 h after dosing interval (AUC0-24) values in subjects with mild, moderate and severe hepatic impairment increased by approximately 2·2-, 4·9- and 7·6-fold, respectively. The most frequent adverse events (AEs) exhibited in this study were similar to those seen with prostacyclin and its analogues and with AEs seen in other clinical studies with oral treprostinil (e.g. headache, diarrhoea and nausea). The overall incidence of all AEs and the specific events of headache and nausea increased with severity of hepatic impairment. WHAT IS NEW AND CONCLUSION: Based on these results, dosage adjustments should be performed in subjects with hepatic impairment. AIMS: Inflammation plays critical roles in atherosclerosis. Chemokines are responsible for leukocyte trafficking and involve in inflammatory diseases. Macrophage inflammatory protein 1α (MIP-1α) has been implicated in atherosclerotic lesion formation. Prostaglandin I2 (PGI2) analog, used in pulmonary hypertension, has been reported to have anti-inflammatory functions. However, little is known about its role in the MIP-1α production in human monocytes. METHODS: We investigated the effects of 3 conventional (iloprost, beraprost, and treprostinil) and 1 new (ONO-1301) PGI2 analogs, on the expression of MIP-1α expression in human monocytes. Human primary monocytes from control subjects and THP-1 cell line were treated with PGI2 analogs, with or without lipopolysaccharide (LPS) stimulation. Supernatants were harvested to measure MIP-1α levels by enzyme-linked immunosorbent assay. To explore which receptors involved the effects of PGI2 analogs on the expression of MIP-1α expression, I prostanoid (IP) and E prostanoid, peroxisome proliferator-activated receptor (PPAR)-α, and PPAR-r receptor antagonists were used to pretreat THP-1 cells. Forskolin, a cyclic adenosine monophosphate (cAMP) activator, was also used to further confirm the cAMP involvement on the effect of PGI2 analogs in MIP-1α production. RESULTS: Three PGI2 analogs could suppress LPS-induced MIP-1α production in THP-1 cells and human primary monocytes. ONO-1301 had a similar effect. CAY 10449, an IP receptor antagonist, could reverse the suppressive effects on MIP-1α production of iloprost. Forskolin, a cAMP activator, also suppressed MIP-1α production in THP-1 cells. CONCLUSIONS: Prostaglandin I2 analogs suppressed LPS-induced MIP-1α production in human monocytes via the IP receptor and cAMP pathway. The PGI2 analog may be potential in the treatment for atherosclerosis.

Which are the characteristics of the Meier-Gorlin syndrome?

The Meier-Gorlin syndrome is a rare autosomal recessive disorder, characterized by the association of bilateral microtia, aplasia or hypoplasia of the patellae, and severe pre- and postnatal growth retardation.

The Meier-Gorlin syndrome or ear, patella, short stature syndrome (MIM 224690) is a rare autosomal recessive disorder, characterized by the association of bilateral microtia, aplasia/hypoplasia of the patellae, and severe pre- and postnatal growth retardation. Twenty-one cases have been reported in literature thus far. Here we report on eight patients from seven families and compare them with previously described cases. One of the present cases had previously undescribed genital anomalies. There is a difference in facial characteristics between patients reported in early infancy and those described at older age; follow-up of patients is needed to substantiate this changing facial phenotype. We recommend radiographic survey of the patellae in patients at older age to investigate the weight of absent or hypoplastic patellae in the diagnosis of the syndrome. We report on an Italian boy with the Meier-Gorlin syndrome (ear-patella-short stature syndrome). This rare autosomal recessive disorder comprises the triad of microtia, absent patellae, and growth retardation with prenatal onset. The patient had also an acute torsion of his left spermatic cord, a condition related to a congenital defect of the tunica vaginalis. Because this syndrome had been suggested as the human equivalent of the short ear mouse [Lacombe et al., 1994: Ann. Genet. 37:184-191], a mutation analysis of the BMP5 gene was performed and found normal. The LMX1B and the SHOX genes were also evaluated considering the absent patellae and short stature, respectively, and were found normal as well. The Meier-Gorlin syndrome (MGS) is a rare autosomal recessive disorder, characterized by bilateral microtia, aplasia or hypoplasia of the patellae, and severe intrauterine and post-natal growth retardation. We describe the phenotype and report the medical history of a 25-year-old woman with MGS. Her phenotypic evolution was characterized by severe growth retardation with decelerated growth of the head and subsequently a relatively small head, normal intelligence, alteration of the facial features to a more proportionate appearance, improvement of joint function and incomplete breast development. Other characteristics of her phenotype in adulthood include a cheerful personality, a high forehead and accentuated naso-labial folds, relatively very small ears, hypoplastic breasts, and normal menstruation. Meier-Gorlin syndrome (MGS) is a rare autosomal recessive disorder characterized by primordial dwarfism, microtia, and patellar aplasia/hypoplasia. Recently, mutations in the ORC1, ORC4, ORC6, CDT1, and CDC6 genes, encoding components of the pre-replication complex, have been identified. This complex is essential for DNA replication and therefore mutations are expected to impair cell proliferation and consequently could globally reduce growth. However, detailed growth characteristics of MGS patients have not been reported, and so this is addressed here through study of 45 MGS patients, the largest cohort worldwide. Here, we report that growth velocity (length) is impaired in MGS during pregcy and first year of life, but, thereafter, height increases in paralleled normal reference centiles, resulting in a mean adult height of -4.5 standard deviations (SD). Height is dependent on ethnic background and underlying molecular cause, with ORC1 and ORC4 mutations causing more severe short stature and microcephaly. Growth hormone therapy (n = 9) was generally ineffective, though in two patients with significantly reduced IGF1 levels, growth was substantially improved by GH treatment, with 2SD and 3.8 SD improvement in height. Growth parameters for monitoring growth in future MGS patients are provided and as well we highlight that growth is disproportionately affected in certain structures, with growth related minor genital abnormalities (42%) and mammary hypoplasia (100%) frequently present, in addition to established effects on ears and patellar growth. A homozygous mutational change in the Ataxia-Telangiectasia and RAD3 related (ATR) gene was previously reported in two related families displaying Seckel Syndrome (SS). Here, we provide the first identification of a Seckel Syndrome patient with mutations in ATRIP, the gene encoding ATR-Interacting Protein (ATRIP), the partner protein of ATR required for ATR stability and recruitment to the site of DNA damage. The patient has compound heterozygous mutations in ATRIP resulting in reduced ATRIP and ATR expression. A nonsense mutational change in one ATRIP allele results in a C-terminal truncated protein, which impairs ATR-ATRIP interaction; the other allele is abnormally spliced. We additionally describe two further unrelated patients native to the UK with the same novel, heterozygous mutations in ATR, which cause dramatically reduced ATR expression. All patient-derived cells showed defective DNA damage responses that can be attributed to impaired ATR-ATRIP function. Seckel Syndrome is characterised by microcephaly and growth delay, features also displayed by several related disorders including Majewski (microcephalic) osteodysplastic primordial dwarfism (MOPD) type II and Meier-Gorlin Syndrome (MGS). The identification of an ATRIP-deficient patient provides a novel genetic defect for Seckel Syndrome. Coupled with the identification of further ATR-deficient patients, our findings allow a spectrum of clinical features that can be ascribed to the ATR-ATRIP deficient sub-class of Seckel Syndrome. ATR-ATRIP patients are characterised by extremely severe microcephaly and growth delay, microtia (small ears), micrognathia (small and receding chin), and dental crowding. While aberrant bone development was mild in the original ATR-SS patient, some of the patients described here display skeletal abnormalities including, in one patient, small patellae, a feature characteristically observed in Meier-Gorlin Syndrome. Collectively, our analysis exposes an overlapping clinical manifestation between the disorders but allows an expanded spectrum of clinical features for ATR-ATRIP Seckel Syndrome to be defined. The Meier-Gorlin syndrome (MGS) or ear, patella, short stature syndrome (MIM #224690) is a rare disorder with bilateral microtia, aplasia or hypoplasia of the patellae and severe intra-uterine and post-natal growth retardation. We report the case of a 10-year-old male with MGS diagnosis, his parents were related, he also showed conductive hearing loss and maloclussion and long upper central incisors, more importantly he had asymmetry of the left cerebral hemisphere and ventricular system, his intelligence was normal. As far as we know, these abnormalities have not been previously described in patients with MGS and the present report corresponds to the first Mexican case described so far.

Which enzyme is deficient in Gaucher's disease?

Gaucher's disease is caused by deficient lysosomal glucocerebrosidase activity

Alglucerase is a mannose-terminated form of human placental glucocerebrosidase, developed to treat patients with Gaucher's disease. Functional glucocerebrosidase is deficient in Gaucher's disease, an autosomal recessive lipid storage disorder that affects people of all ethnic backgrounds, but has a higher incidence among East European Jews (Ashkenazim). Gaucher's disease manifests with hepatosplenomegaly, bleeding disorders and bone disease, with the more rare subtypes (types 2 and 3) featuring neurological dysfunction. Prior to the development of enzyme replacement therapy, treatment for Gaucher's disease was mainly symptomatic relief. Primary treatment with glucocerebrosidase focuses on removal of the lipid metabolite that causes the pathology. Because of the rarity of Gaucher's disease clinical trials are small, and much of the data investigating alglucerase therapy have been obtained from studies of patients with type 1 disease, the prevalent subtype. Nonetheless, after intravenous administration of alglucerase, improvements are evident within 6 months of therapy. Patients have increased haemoglobin levels and platelet counts, and decreased incidences of epistaxis and bruising. Spleen and liver size are reduced, and skeletal parameters improve. Children gain height and most patients receiving alglucerase therapy are able to resume work and daily activities. Alglucerase is well tolerated, with few mild adverse reactions reported. Although the pharmacokinetic and pharmacodynamic information for alglucerase is limited, its unequivocal efficacy justifies enzyme replacement therapy with this compound as first-line treatment for patients with Gaucher's disease, for whom treatment options are limited. BACKGROUND AND METHODS: Gaucher's disease, the most prevalent of the sphingolipid storage disorders, is caused by a deficiency of the enzyme glucocerebrosidase (glucosylceramidase). Enzyme replacement was proposed as a therapeutic strategy for this disorder in 1966. To assess the clinical effectiveness of this approach, we infused macrophage-targeted human placental glucocerebrosidase (60 IU per kilogram of body weight every 2 weeks for 9 to 12 months) into 12 patients with type 1 Gaucher's disease who had intact spleens. The frequency of infusions was increased to once a week in two patients (children) during part of the trial because they had clinically aggressive disease. RESULTS: The hemoglobin concentration increased in all 12 patients, and the platelet count in 7. Serum acid phosphatase activity decreased in 10 patients during the trial, and the plasma glucocerebroside level in 9. Splenic volume decreased in all patients after six months of treatment, and hepatic volume in five. Early signs of skeletal improvements were seen in three patients. The enzyme infusions were well tolerated, and no antibody to the exogenous enzyme developed. CONCLUSIONS: Intravenous administration of macrophage-targeted glucocerebrosidase produces objective clinical improvement in patients with type 1 Gaucher's disease. The hematologic and visceral responses to enzyme replacement develop more rapidly than the skeletal response. Structure/function relationships of acid beta-glucosidase, the enzyme deficient in Gaucher disease, were evaluated by characterizing the proteins expressed from cDNAs encoding normal and mutant enzymes. Twenty-two Gaucher disease mutations or created mutations were expressed in Spodoptera frugiperda (Sf9) cells and analyzed for catalytic properties, stability, inhibitor binding, and modifier interactions. Many Gaucher disease mutations encoded highly disruptive amino acid substitutions (e.g. P289L and D409V) and produced severely compromised proteins with very reduced activity (kcat < 1% of normal) and/or stability. Six mutant enzymes had sufficient catalytic activity (kcat approximately 5-30% of normal) for extensive studies. The highly conservative substitutions, i.e. F216Y or S364T and V394L, led to severe, but selective, abnormalities of enzyme stability or large decreases in catalytic activity, respectively. The T323I, N370S, and V394L enzymes interacted abnormally with active site-directed inhibitors and localized these residues to the glycon binding region. Selected mutant enzymes were poorly activated by phosphatidylserine (V394L, L444P, and R463C) or by saposin C (L444P and T323I), indicating that the enzyme sites for interaction with these activators were within the carboxyl one-third of the enzyme. Substitutions of Ser, Glu, and/or Gly at residues Asp-443 and/or Asp-445 demonstrated important steric roles for these residues in the active site, but neither is the catalytic nucleophile. Together with previous studies, the present analyses provide an insight into the pathogenesis of Gaucher disease and the functional organization of acid beta-glucosidase. BACKGROUND: Liver transplantation for type IV glycogen storage disease (branching-enzyme deficiency) results in the resorption of extrahepatic deposits of amylopectin, but the mechanism of resorption is not known. METHODS: We studied two patients with type IV glycogen storage disease 37 and 91 months after liver transplantation and a third patient with lysosomal glucocerebrosidase deficiency (type 1 Gaucher's disease), in whom tissue glucocerebroside deposition had decreased 26 months after liver replacement, to determine whether the migration of cells from the allograft (microchimerism) could explain the improved metabolism of enzyme-deficient tissues in the recipient. Samples of blood and biopsy specimens of the skin, lymph nodes, heart, bone marrow, or intestine were examined immunocytochemically with the use of donor-specific monoclonal anti-HLA antibodies and the polymerase chain reaction, with preliminary amplification specific to donor alleles of the gene for the beta chain of HLA-DR molecules, followed by hybridization with allele-specific oligonucleotide probes. RESULTS: Histopathological examination revealed that the cardiac deposits of amylopectin in the patients with glycogen storage disease and the lymph-node deposits of glucocerebroside in the patient with Gaucher's disease were dramatically reduced after transplantation. Immunocytochemical analysis showed cells containing the HLA phenotypes of the donor in the heart and skin of the patients with glycogen storage disease and in the lymph nodes, but not the skin, of the patient with Gaucher's disease. Polymerase-chain-reaction analysis demonstrated donor HLA-DR DNA in the heart of both patients with glycogen storage disease, in the skin of one of them, and in the skin, intestine, blood, and bone marrow of the patient with Gaucher's disease. CONCLUSIONS: Systemic microchimerism occurs after liver allotransplantation and can ameliorate pancellular enzyme deficiencies. Alglucerase is a modified form of human placental glucocerebrosidase used as enzyme replacement therapy for patients with Gaucher's disease, in whom functional glucocerebrosidase is deficient. Alglucerase has provided a breakthrough in treatment for patients with this relatively rare disease. With alglucerase infusions typical disease manifestations are ameliorated or normalised: hepatosplenomegaly is reduced, haematological parameters improve, and patients experience an increased quality of life usually within 4 to 6 months of treatment. Parameters of bone disease also respond, but generally over a longer period of treatment. Alglucerase is well tolerated by children and adults, with few adverse effects reported. Seroconversion occurs in approximately 15% of patients on high-dose therapy, but does not appear to affect the efficacy of treatment. Several dosage regimens have been used to deliver alglucerase, and the comparative benefits of these remain controversial. High-dose regimens of 60 IU/kg bodyweight administered every 2 weeks are clearly effective; however, smaller dosages given more frequently are also effective and incur a greatly reduced acquisition cost. Patient responses are variable, and the dosage regimen should be tailored to individual needs. Dosage regimens may be considerably reduced for the maintece phase of treatment, but clinical experience is as yet insufficient to establish the minimum dosages required in the long term. Acquisition cost of alglucerase is $US3.70 per unit (1994 US dollars); thus, a dosage regimen of 60 IU/kg bodyweight administered every 2 weeks for a patient weighing 70kg costs $US404,040 per year. The minimal costs per quality-adjusted life year saved (QALY) have been estimated for 3 dosage regimens over a 10-year period. Cost per QALY was $US147,000 for 60 IU/kg bodyweight administered every 2 weeks, $US75,000 for 30 IU/kg every 2 weeks, and $US49,000 for 2.3 IU/kg administered 3 times per week. These costs were calculated assuming immediate death with no treatment, which suggests that the actual costs per QALY for most patients with type 1 or 3 disease are likely to be much higher. Drug administration costs may become a significant part of the cost during maintece therapy; in addition, possible cost savings due to increased patient productivity and reduced palliative treatments remain unresolved. Although some patients may obtain increased benefit from high-dosage regimens, the very high cost may preclude general use of these regimens. Healthcare resources consumed by alglucerase therapy represent a large opportunity cost for other therapeutic areas.(ABSTRACT TRUNCATED AT 400 WORDS) Author information: (1)Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD, 20892-4405, USA. (2)Section on Molecular Neurogenetics, National Institute of Mental Health, 49 Convent Drive MSC4405, 49/B1EE16, Bethesda, MD, 20892-4405, USA. (3)Laboratory of Neurotoxicology, National Institute of Mental Health, Bethesda, MD, 20892-4405, USA. (4)Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD, 20892-4405, USA. [email protected]. (5)Section on Molecular Neurogenetics, National Institute of Mental Health, 49 Convent Drive MSC4405, 49/B1EE16, Bethesda, MD, 20892-4405, USA. [email protected]. Alteration G2019S in the leucine-rich repeat kinase 2 gene (LRRK2) has been identified in several populations of patients with parkinsonism, including Ashkenazi Jewish subjects with Parkinson disease. Mutations in glucocerebrosidase (GBA), the enzyme deficient in Gaucher disease, are also identified at an increased frequency among Parkinson probands, including those of Ashkenazi Jewish ancestry. A Taqman Assay-by-Design SNP genotyping strategy was utilized to establish whether G2019S was found in association with GBA mutations. Among 37 subjects with parkinsonism who were heterozygous for a GBA mutation, none carried G2019S. Furthermore, G2019S was not found in 18 patients with Gaucher disease who developed parkinsonian manifestations and 11 other Gaucher probands with parkinsonism in a first degree relative. Among 45 patients with Gaucher disease without a history of parkinsonism, one G2019S carrier was found. These findings suggest that GBA and LRRK2 mutations are discrete risk factors for parkinsonism in both Ashkenazi Jewish and non-Jewish subjects. PURPOSE: Gaucher disease (GD) is an autosomal recessive lysosomal disorder caused by a deficiency of glucocerebrosidase. The neurologic manifestations of GD patients have to date been refractory to any treatment approach. We present a report of a neuronopathic GD patient whose myoclonic epilepsy improved after combination therapy with imiglucerase and miglustat. METHODS: In an adult type 3 GD patient who, despite good visceral and analytic response to ERT, developed progressive neurologic deterioration with marked myoclonic epilepsy and dystonia, we added miglustat to the enzyme-replacement therapy. RESULTS: After 2 years of combined miglustat (200 mg, 3 t.i.d.) and imiglucerase (60 IU/kg every 2 weeks), generalized tonic-clonic seizures decreased, speech improved, and the general neurologic clinical picture improved markedly. The EEG showed a reduction in focal and generalized paroxysmal discharges. No significant adverse effects were observed. CONCLUSIONS: Combined imiglucerase and miglustat therapy may be beneficial for some neuronopathic forms of GD. Although Gaucher disease is a rare disorder, recent developments in novel means for therapeutic intervention have invigorated both academic research and pharmaceutical industry discovery programmes. The common mutations found in the lysosomal enzyme deficient in Gaucher disease, beta-glucocerebrosidase, earmark these proteins for destruction by the endoplasmic reticulum-localised protein folding machinery, resulting in enzyme insufficiency, lysosomal glycolipid storage and subsequent pathology. However, many of these mutants can be rescued from global misfolding to preserve glycolipid substrate binding and eventual catalysis in the lysosome, by the addition of subinhibitory concentrations of pharmacologically active small molecules. This novel, chaperon-mediated approach has benefited from insights into the molecular understanding of beta-glucocerebrosidase structure, drug design and development in cellular models for disease. Gaucher's disease is due to glucocerebrosidase deficiency which is responsible for the accumulation of non degraded glucosylceramide within the lysosomes of macrophages: these "Gaucher cells", overloaded and alternatively activated, release in patient's plasma numerous compounds (cytokines, chemokines, hydrolases...) some of which contribute to the various tissue damages. Some of these compounds are surrogate biomarkers which contribute to the evaluation of disease severity, progression and stabilisation or regression during treatment. To date, the most interesting biomarkers are chitotriosidase and the chemokine CCL18/PARC, especially in chitotriosidase deficient patients. These biomarkers together with the clinical evaluation help to therapeutic choice (treatment by enzyme replacement therapy or substrate reduction therapy) and initiation decision, response follow-up and dose adjustments. Biomarkers should be assessed every 12 months together with clinical evaluation in patients not receiving specific treatments. An assessment every 3 months is recommended during the first year of treatment. Then when clinical goals have been achieved, the frequency can be reduced to every 12 months if the therapeutic scheme is not modified. BACKGROUND: Gaucher's disease is caused by deficient lysosomal glucocerebrosidase activity. Intravenous enzyme replacement therapy with imiglucerase (Cerezyme, Genzyme Corporation, Cambridge, MA), a recombit human glucocerebrosidase, ameliorates systemic manifestations such as hepatosplenomegaly, anemia, thrombocytopenia and skeletal abnormalities in patients with type 1 (non-neuronopathic) and type 3 (chronic neuronopathic) Gaucher's disease. OBJECTIVE/METHODS: The aim of this study was to identify and comment on the current issues related to imiglucerase for Gaucher's disease based on a review of published English language literature and personal clinical experience. RESULTS: The following topics were covered with respect to imiglucerase: development, pharmacokinetics, preparation and administration, efficacy, pediatrics, pregcy, type 3 Gaucher's disease, dosing, treatment interruptions, safety and alternative pharmacological therapies. CONCLUSION: Imiglucerase is safe and well tolerated. In addition, it corrects the hepatic, splenic, hematologic and bone abnormalities observed with types 1 and 3 Gaucher's disease effectively and enhances health-related quality of life. Gaucher disease (GD) is a lysosomal storage disorder, caused by deficient activity of the enzyme glucocerebrosidase. GD is classically divided into three major phenotypes. The most prevailing form is type 1, which presents with variable hepatosplenomegaly, cytopenia, and/or bone disease. In adult patients with mild manifestations, progress of disease might be slow or even absent. As a consequence, treatment with intravenous enzyme replacement or substrate reduction is not always necessary. In the Netherlands, the follow-up of GD patients is centralized, which allows detailed investigation of untreated patients. A retrospective study was conducted in 18 type 1 GD patients, (2 teenagers: 15 and 16 years of age at first visit) who were not treated for at least one year. The chitotriosidase activity, platelet count, hemoglobin level, lumbar bone marrow fat content measured with quantitative chemical shift imaging (QCSI), liver ratio (ml/kg body weight), and spleen volume were recorded. Criteria were developed to score regression, stability or progression of disease. During a mean follow up of 4.5 years (range 1.1-12.2) seven patients (39%) showed spontaneous regression of GD. Eight patients (44%) were stable. Two patients had progressive disease, solely based upon a sustained increase in chitotriosidase activity. A pediatric patient had an increase in splenomegaly but an improvement in bone marrow fat fraction, probably due to aging. Nine patients fulfilled the local criteria to start treatment at first visit, of whom six started treatment within 1.1 to 6.8 years. The other three refused therapy, but nevertheless showed stability or even regression of the disease during a follow up of 4.6, 9.5 and 11.4 years respectively. None of the parameters was predictive of progression or regression of disease. In conclusion, GD in adults can, in some cases, regress spontaneously. No parameters for accurately predicting future disease course exist. The presynaptic protein α-synuclein (α-syn), particularly in its amyloid form, is widely recognized for its involvement in Parkinson disease (PD). Recent genetic studies reveal that mutations in the gene GBA are the most widespread genetic risk factor for parkinsonism identified to date. GBA encodes for glucocerebrosidase (GCase), the enzyme deficient in the lysosomal storage disorder, Gaucher disease (GD). In this work, we investigated the possibility of a physical linkage between α-syn and GCase, examining both wild type and the GD-related N370S mutant enzyme. Using fluorescence and nuclear magnetic resoce spectroscopy, we determined that α-syn and GCase interact selectively under lysosomal solution conditions (pH 5.5) and mapped the interaction site to the α-syn C-terminal residues, 118-137. This α-syn-GCase complex does not form at pH 7.4 and is stabilized by electrostatics, with dissociation constants ranging from 1.2 to 22 μm in the presence of 25 to 100 mm NaCl. Intriguingly, the N370S mutant form of GCase has a reduced affinity for α-syn, as does the inhibitor conduritol-β-epoxide-bound enzyme. Immunoprecipitation and immunofluorescence studies verified this interaction in human tissue and neuronal cell culture, respectively. Although our data do not preclude protein-protein interactions in other cellular milieux, we suggest that the α-syn-GCase association is favored in the lysosome, and that this noncovalent interaction provides the groundwork to explore molecular mechanisms linking PD with mutant GBA alleles. Mutations in GBA, the gene encoding glucocerebrosidase, the enzyme deficient in Gaucher disease, are common risk factors for Parkinson disease, as patients with Parkinson disease are over five times more likely to carry GBA mutations than healthy controls. Patients with GBA mutations generally have an earlier onset of Parkinson disease and more cognitive impairment than those without GBA mutations. We investigated whether GBA mutations alter the neurobiology of Parkinson disease, studying brain dopamine synthesis and resting regional cerebral blood flow in 107 subjects (38 women, 69 men). We measured dopamine synthesis with (18)F-fluorodopa positron emission tomography, and resting regional cerebral blood flow with H(2)(15)O positron emission tomography in the wakeful, resting state in four study groups: (i) patients with Parkinson disease and Gaucher disease (n = 7, average age = 56.6 ± 9.2 years); (ii) patients with Parkinson disease without GBA mutations (n = 11, 62.1 ± 7.1 years); (iii) patients with Gaucher disease without parkinsonism, but with a family history of Parkinson disease (n = 14, 52.6 ± 12.4 years); and (iv) healthy GBA-mutation carriers with a family history of Parkinson disease (n = 7, 50.1 ± 18 years). We compared each study group with a matched control group. Data were analysed with region of interest and voxel-based methods. Disease duration and Parkinson disease functional and staging scores were similar in the two groups with parkinsonism, as was striatal dopamine synthesis: both had greatest loss in the caudal striatum (putamen Ki loss: 44 and 42%, respectively), with less reduction in the caudate (20 and 18% loss). However, the group with both Parkinson and Gaucher diseases showed decreased resting regional cerebral blood flow in the lateral parieto-occipital association cortex and precuneus bilaterally. Furthermore, two subjects with Gaucher disease without parkinsonian manifestations showed diminished striatal dopamine. In conclusion, the pattern of dopamine loss in patients with both Parkinson and Gaucher disease was similar to sporadic Parkinson disease, indicating comparable damage in midbrain neurons. However, H(2)(15)O positron emission tomography studies indicated that these subjects have decreased resting activity in a pattern characteristic of diffuse Lewy body disease. These findings provide insight into the pathophysiology of GBA-associated parkinsonism. Lysosomes require the presence of many specialized proteins to facilitate their roles in cellular maintece. One such protein that has proven to be an important player in the lysosomal field is lysosomal integral membrane protein-2 (LIMP-2), encoded by the gene SCARB2. LIMP-2 is required for the normal biogenesis and maintece of lysosomes and endosomes and has been identified as the specific receptor for glucocerebrosidase, the enzyme deficient in Gaucher disease. Research into LIMP-2 and the SCARB2 gene indicate that it may be a factor contributing to the clinical heterogeneity seen among patients with Gaucher disease. Mutations in SCARB2 have also been identified as the cause of action myoclonus renal failure (AMRF), and in some cases progressive myoclonic epilepsy. A total of 14 disease-causing SCARB2 mutations have been identified to date. The role of LIMP-2 in human pathology has expanded with its identification as a component of the intercalated disk in cardiac muscle and as a receptor for specific enteroviruses, two uticipated findings that reaffirm the myriad roles of lysosomal proteins. Studies into the full impact of LIMP-2 deficiency and the LIMP2/glucocerebrosidase molecular pathway will lead to a better understanding of disease pathogenesis in Gaucher disease and AMRF, and to new insights into lysosomal processing, trafficking and function. Mutations in glucocerebrosidase (GCase), the enzyme deficient in Gaucher disease, are a common genetic risk factor for the development of Parkinson disease and related disorders, implicating the role of this lysosomal hydrolase in the disease etiology. A specific physical interaction exists between the Parkinson disease-related protein α-synuclein (α-syn) and GCase both in solution and on the lipid membrane, resulting in efficient enzyme inhibition. Here, neutron reflectometry was employed as a first direct structural characterization of GCase and α-syn·GCase complex on a sparsely-tethered lipid bilayer, revealing the orientation of the membrane-bound GCase. GCase binds to and partially inserts into the bilayer with its active site most likely lying just above the membrane-water interface. The interaction was further characterized by intrinsic Trp fluorescence, circular dichroism, and surface plasmon resoce spectroscopy. Both Trp fluorescence and neutron reflectometry results suggest a rearrangement of loops surrounding the catalytic site, where they extend into the hydrocarbon chain region of the outer leaflet. Taking advantage of contrasting neutron scattering length densities, the use of deuterated α-syn versus protiated GCase showed a large change in the membrane-bound structure of α-syn in the complex. We propose a model of α-syn·GCase on the membrane, providing structural insights into inhibition of GCase by α-syn. The interaction displaces GCase away from the membrane, possibly impeding substrate access and perturbing the active site. GCase greatly alters membrane-bound α-syn, moving helical residues away from the bilayer, which could impact the degradation of α-syn in the lysosome where these two proteins interact.

What is the role of Hsp90 inhibition in cancer therapy?

Hsp90 inhibition is followed by G1/S cell cycle arrest, downregulation of key signalling proteins such as IGF-IR, Akt, IKK-α, IKK-β, FOXO1, ERK1/2 and c-Met, and sequestration-mediated inactivation of NF-κB, resulting in disruption of oncogenic signalling integrity, reduced cell proliferation, decline of cell motility, enhanced apoptotic cell death, and finally, sensitization of cancer cells to additional chemotherapy and/or radiotherapy.

For metastatic bladder cancer patients, systemic cisplatin (CDDP)-based combination chemotherapy is the first-line choice of treatment. Although up to 70% of advanced bladder cancer patients initially show good tumor response to this form of combination chemotherapy, over 90% of good responders relapse and eventually die of the disease. According to the cancer stem cell theory, this phenomenon is attributable to the re-growth of bladder cancer-initiating cells (BCICs) that have survived chemotherapy. In this study, the authors have isolated BCICs from cultured human bladder cancer cells to analyze their sensitivity to CDDP and to investigate whether heat-shock protein 90 (Hsp90) inhibitors potentiate the cytotoxicity of CDDP on BCICs. First, the authors have confirmed that a CD44+ subpopulation of 5637 cells met the requirements to be considered tumor-initiating cells. These BCICs were more resistant to CDDP and exhibited more activity in the Akt and ERK oncogenic signaling pathways when compared with their CD44- counterparts. The Hsp90 inhibitor 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG), which simultaneously inactivated both Akt and ERK signaling at noncytocidal concentrations, synergistically potentiated the cytotoxicity of CDDP against BCICs by enhancing CDDP-induced apoptosis in vitro. The potentiating effect of 17-DMAG was more effective than a combination of the two inhibitors specific for the Akt and ERK pathways. Finally, the authors have confirmed that, though human BCIC xenografts exhibited resistance to a single administration of CDDP and the Hsp90 inhibitor 17-(allylamino)-17-demethoxygeldanamycin (17-AAG), 17-AAG sensitized them to CDDP in a mouse model. These data encourage clinical trials of Hsp90 inhibitors as they may improve therapeutic outcomes of CDDP-based combination chemotherapy against advanced bladder cancer. BACKGROUND: Geldanamycin (GA) can be considered a relatively new component with a promising mode of action against human maligcies. It specifically targets heat shock protein 90 (Hsp90) and interferes with its function as a molecular chaperone. METHODS: In this study, we have investigated the effects of geldanamycin on the regulation of Hsp90-dependent oncogenic signaling pathways directly implicated in cell cycle progression, survival and motility of human urinary bladder cancer cells. In order to assess the biological outcome of Hsp90 inhibition on RT4 (grade I) and T24 (grade III) human urinary bladder cancer cell lines, we applied MTT assay, FACS analysis, Western blotting, semi-quantitative (sq) RT-PCR, electrophoretic mobility shift assay (EMSA), immunofluorescence and scratch-wound assay. RESULTS: We have herein demonstrated that, upon geldanamycin treatment, bladder cancer cells are prominently arrested in the G1 phase of cell cycle and eventually undergo programmed cell death via combined activation of apoptosis and autophagy. Furthermore, geldanamycin administration proved to induce prominent downregulation of several Hsp90 protein clients and downstream effectors, such as membrane receptors (IGF-IR and c-Met), protein kinases (Akt, IKKα, IKKβ and Erk1/2) and transcription factors (FOXOs and NF-κΒ), therefore resulting in the impairment of proliferative -oncogenic- signaling and reduction of cell motility. CONCLUSIONS: In toto, we have evinced the dose-dependent and cell line-specific actions of geldanamycin on cell cycle progression, survival and motility of human bladder cancer cells, due to downregulation of critical Hsp90 clients and subsequent disruption of signaling -oncogenic- integrity.

Which is the most common type of pediatric cerebellar tumor?

Medulloblastoma is the most common malignant cerebellar tumor seen in the pediatric age group, which has a known ability to metastasize extraneurally.

Medulloblastoma is a maligt cerebellar tumor seen primarily in the pediatric age group that has a known ability to metastasize extraneurally. The skeleton is the most common site of extraneural metastases, but metastases to the bone marrow can also occur. Four cases of medulloblastoma metastatic to the marrow are reported. In addition, 31 cases from the medical literature are reviewed. Clinical features include bone tenderness, cytopenias and elevated serum alkaline phosphatase and lactic dehydrogenase levels. Skeletal involvement, especially of the pelvic bones, is frequently seen radiographically. Weight loss, soft tissue masses and a requirement for blood transfusion are also associated features. Marrow biopsy specimens are characterized by the presence of a small cell tumor often with fibrosis, necrosis and osteoblastic activity. The symptomatic response to chemotherapy is rapid, but chemotherapy resistance appears quickly. Only 1 in 4 cases diagnosed antemortem in this review lived for more than a year. We conclude that marrow aspiration and biopsy are indicated in the evaluation of patients with medulloblastoma and may serve to diagnose the cause of cytopenias, to verify extraneural spread and to provide prognostic information. Pediatric central nervous system neoplasms include a spectrum of both glial and nonglial tumors that differ significantly in location and biological behavior from those of adults. Brain tumors in infants and children most often arise from central neuroepithelial tissue, whereas a significant number of adult tumors arise from central nervous system coverings (e.g., meningioma), adjacent tissue (e.g., pituitary adenoma), or metastases. Most adult brain tumors are supratentorial maligt gliomas, whereas the most common maligt pediatric brain tumor is the cerebellar primitive neuroectodermal tumor (medulloblastoma). This article reviews neuropathological characteristics of the more common pediatric brain tumors. Entities, such as the brainstem glioma, and less common neoplasms like the desmoplastic infantile ganglioglioma and the central nervous system atypical teratoid/rhabdoid tumor are reviewed because they occur almost exclusively in children. Known cytogenetic and molecular characteristics of childhood brain tumors are also reviewed. Medulloblastoma (MB) is the most common maligt pediatric brain tumor and is thought to arise from genetic anomalies in developmental pathways required for the normal maturation of the cerebellar cortex, notably developmental pathways for granule cell progenitor (GCP) neurogenesis. Over the past decade, a wide range of studies have identified genes and their regulators within signaling pathways, as well as noncoding RNAs, that have crucial roles in both normal cerebellar development and pathogenesis. These include the Notch, Wnt/β-catenin, bone morphogenic proteins (Bmp) and Sonic Hedgehog (Shh) pathways. In this review, we highlight the function of these pathways in the growth of the cerebellum and the formation of MB. A better understanding of the developmental origins of these tumors will have significant implications for enhancing the treatment of this important childhood cancer. Medulloblastoma (MDB) is the most common maligt cerebellar tumor in children. Because of the significant rate of mortality and treatment-related morbidity, the identification of prognostic factors could lead to a more accurate selection of patients who can benefit from a less aggressive therapy and improve risk stratification. Survivin is an inhibitor of apoptosis protein (IAP), the expression of which has been associated with worse prognosis in MDB. However, both of its subcellular localizations may contribute to tumor progression, and ultimately, survivin subcellular localization prognostic value depends on tumor type biological features. The goal of this study was to analyze these survivin features in the pediatric MDB tumor samples and its impact on clinical outcome. Survivin expression and subcellular localization were accessed by immunohistochemistry in a series of 41 tumor samples. Kaplan-Meier survival curves were compared using the log-rank test. Survivin expression ranged from completely absent to fully present in a notably higher pattern of nuclear localization than cytoplasmic (19 of 41 versus 4 of 41, respectively). However, survivin expression and subcellular localization were not associated with five-year overall survival or metastasis status at diagnosis, which was the only statistically significant prognostic factor in our series (p = 0.008). Taken together, our results suggest that survivin expression should be further studied in large, multicenter series to determine its accurate impact on prognosis and pathobiology of pediatric MDB. Mouse models have increased our understanding of the pathogenesis of medulloblastoma (MB), the most common maligt pediatric brain tumor that often forms in the cerebellum. A major goal of ongoing research is to better understand the early stages of tumorigenesis and to establish the genetic and environmental changes that underlie MB initiation and growth. However, studies of MB progression in mouse models are difficult due to the heterogeneity of tumor onset times and growth patterns and the lack of clinical symptoms at early stages. Magnetic resoce imaging (MRI) is critical for noninvasive, longitudinal, three-dimensional (3D) brain tumor imaging in the clinic but is limited in resolution and sensitivity for imaging early MBs in mice. In this study, high-resolution (100 μm in 2 hours) and high-throughput (150 μm in 15 minutes) manganese-enhanced MRI (MEMRI) protocols were optimized for early detection and monitoring of MBs in a Patched-1 (Ptch1) conditional knockout (CKO) model. The high tissue contrast obtained with MEMRI revealed detailed cerebellar morphology and enabled detection of MBs over a wide range of stages including pretumoral lesions as early as 2 to 3 weeks postnatal with volumes close to 0.1 mm(3). Furthermore, longitudinal MEMRI allowed noninvasive monitoring of tumors and demonstrated that lesions within and between individuals have different tumorigenic potentials. 3D volumetric studies allowed quantitative analysis of MB tumor morphology and growth rates in individual Ptch1-CKO mice. These results show that MEMRI provides a powerful method for early in vivo detection and longitudinal imaging of MB progression in the mouse brain.

Which is the E3 ubiquitin ligase of Hsp90?

Carboxyl terminus of hsc70-interacting protein (CHIP) can mediate ubiquitination of the 90 kDa heat-shock protein (hsp90) in vitro, with subsequent proteasomal degradation of the chaperone.

The regulation of the aryl hydrocarbon receptor (AhR) protein levels has been an area of keen interest, given its important role in mediating the cellular adaptation and toxic response to several environmental pollutants. The carboxyl terminus of hsc70-interacting protein (CHIP) ubiquitin ligase was previously associated with the regulation of the aryl hydrocarbon receptor, although the mechanisms were not directly demonstrated. In this study, we established that CHIP could associate with the AhR at cellular levels of these two proteins, suggesting a potential role for CHIP in the regulation of the AhR complex. The analysis of the sucrose-gradient-fractionated in vitro translated AhR complexes revealed that CHIP can mediate hsp90 ubiquitination while cooperating with unidentified factors to promote the ubiquitination of mature unliganded AhR complexes. In addition, the immunophilin-like protein XAP2 was able to partially protect the AhR from CHIP-mediated ubiquitination in vitro. This protection required the direct interaction of the XAP2 with the AhR complex. Surprisingly, CHIP silencing in Hepa-1c1c7 cells by siRNA methods did not reveal the function of CHIP in the AhR complex, because it did not affect well-characterized activities of the AhR nor affect its steady-state protein levels. However, the presence of potential compensatory mechanisms may be confounding this particular observation. Our results suggest a model where the E3 ubiquitin ligase CHIP cooperates with other ubiquitination factors to remodel native AhR-hsp90 complexes and where co-chaperones such as the XAP2 may affect the ability of CHIP to target AhR complexes for ubiquitination. The E3 ubiquitin ligase CHIP (C-terminus of Hsc70-interacting protein) is believed to be a central player in the cellular triage decision, as it links the molecular chaperones Hsp70/Hsc70 and Hsp90 to the ubiquitin proteasomal degradation pathway. To better understand the decision process, we determined the affinity of CHIP for Hsp70 and Hsp90 using isothermal titration calorimetry. We analyzed the influence of CHIP on the ATPase cycles of both chaperones in the presence of co-chaperones and a substrate, and determined the ubiquitination efficacy of CHIP in the presence of the chaperones. We found that CHIP has a sixfold higher affinity for Hsp90 compared with Hsc70. CHIP had no influence on ADP dissociation or ATP association, but reduced the Hsp70 cochaperone Hdj1-stimulated single-turnover ATPase rates of Hsc70 and Hsp70. CHIP did not influence the ATPase cycle of Hsp90 in the absence of co-chaperones or in the presence of the Hsp90 cochaperones Aha1 or p23. Polyubiquitination of heat-denatured luciferase and the native substrate p53 was much more efficient in the presence of Hsc70 and Hdj1 than in the presence of Hsp90, indicating that CHIP preferentially ubiquitinates Hsp70-bound substrates. The U-box E3 ubiquitin ligase CHIP (C terminus of Hsc70-interacting protein) binds Hsp90 and/or Hsp70 via its tetratricopeptide repeat (TPR), facilitating ubiquitination of the chaperone-bound client proteins. Mechanisms that regulate the activity of CHIP are, at present, poorly understood. We previously reported that Ca(2+)/S100 proteins directly associate with the TPR proteins, such as Hsp70/Hsp90-organizing protein (Hop), kinesin light chain, Tom70, FKBP52, CyP40, and protein phosphatase 5 (PP5), leading to the dissociation of the interactions of the TPR proteins with their target proteins. Therefore, we have hypothesized that Ca(2+)/S100 proteins can interact with CHIP and regulate its function. GST pulldown assays indicated that Ca(2+)/S100A2 and S100P bind to the TPR domain and lead to interference with the interactions of CHIP with Hsp70, Hsp90, HSF1, and Smad1. In vitro ubiquitination assays indicated that Ca(2+)/S100A2 and S100P are efficient and specific inhibitors of CHIP-mediated ubiquitination of Hsp70, Hsp90, HSF1, and Smad1. Overexpression of S100A2 and S100P suppressed CHIP-chaperone complex-dependent mutant p53 ubiquitination and degradation in Hep3B cells. The association of the S100 proteins with CHIP provides a Ca(2+)-dependent regulatory mechanism for the ubiquitination and degradation of intracellular proteins by the CHIP-proteasome pathway.

Which are the major phycobiliproteins present in cyanobacteria?

Phycobiliproteins are derived from the photosynthetic apparatus of cyanobacteria and eukaryotic algae, and form their large extrinsic antenna complexes called phycobilisomes. Phycobilisomes have a core composed from allophycocyanin (APC) and rods, which are of variable phycobiliprotein composition. C-Phycocyanin (C-Pc) is one of the major light harvesting biliprotein pigments constitutively produced by many cyanobacteria, such as Spirulina platenesis (a blue-green alga). B-Phycoerythrin (B-PE) is an other major light-harvesting pigment found in red algae and cyanobacteria. R-phycoerythrin (R-PE) is the major light-harvesting pigment protein of most red algal phycobilisomes.

A survey of marine unicellular cyanobacterial strains for phycobiliproteins with high phycourobilin (PUB) content led to a detailed investigation of Synechocystis sp. WH8501. The phycobiliproteins of this strain were purified and characterized with respect to their bilin composition and attachment sites. Amino-terminal sequences were determined for the alpha and beta subunits of the phycocyanin and the major and minor phycoerythrins. The amino acid sequences around the attachment sites of all bilin prosthetic groups of the phycocyanin and of the minor phycoerythrin were also determined. The phycocyanin from this strain carries a single PUB on the alpha subunit and two phycocyanobilins on the beta subunit. It is the only phycocyanin known to carry a PUB chromophore. The native protein, isolated in the (alpha beta)2 aggregation state, displays absorption maxima at 490 and 592 nm. Excitation at 470 nm, absorbed almost exclusively by PUB, leads to emission at 644 nm from phycocyanobilin. The major and minor phycoerythrins from strain WH8501 each carry five bilins per alpha beta unit, four PUBs and one phycoerythrobilin. Spectroscopic properties determine that the PUB groups function as energy donors to the sole phycoerythrobilin. Analysis of the bilin peptides unambiguously identifies the phycoerythrobilin at position beta-82 (residue numbering assigned by homology with B-phycoerythrin; Sidler, W., Kumpf, B., Suter, F., Klotz, A. V., Glazer, A. N., and Zuber, H. (1989) Biol. Chem. Hoppe-Seyler 370, 115-124) as the terminal energy acceptor in phycoerythrins. Phycobilisomes, the major light-harvesting complexes of cyanobacteria are multimolecular structures made up of chromophoric proteins called phycobiliproteins and non chromophoric linker polypeptides. We report here the isolation and nucleotide sequence of the genes, cpeA and cpeB, which in Calothrix PCC 7601 encode the alpha and beta subunits of phycoerythrin, one of the major phycobiliproteins. In Calothrix PCC 7601, modulation of the polypeptide composition of the phycobilisomes occurs in response to changes of the light wavelength, a phenomenon known as complementary chromatic adaptation. Under green illumination, cells synthesize phycoerythrin and its two specifically associated linker polypeptides (LR35 and LR36), while under red illumination none of these proteins are detected. Using specific probes, a single transcript (1450 nucleotide long) corresponding to the cpe genes was detected but only in green-light-grown cells, establishing the occurrence of transcriptional regulation for the expression of this operon in response to light wavelength changes. The size of this transcript excludes the possibility that the phycoerythrin-associated LR35 and LR36 could be cotranscribed with the cpeA and cpeB genes. Allophycocyanin (APC) belongs to a family of phycobiliproteins that are well suited as fluorescent reagents for flow cytometric analysis, since they have a broad excitation spectrum, a large Stoke's shift and they fluoresce with a high quantum yield. The widespread use of APC has been limited by the availability of raw material and high cost of the purified phycobiliprotein. We have assessed the suitability of dry, powdered Spirulina platensis, available at health food stores, as an inexpensive source of APC. APC was extracted from Spirulina platensis by overnight treatment with lysozyme, followed by ammonium sulfate precipitation. APC was then separated from phycocyanin (the only other major phycobiliprotein in Spirulina) by elution of bound material from an hydroxylapatite column using an increasing continuous phosphate gradient. APC isolated in this manner retained its normal trimeric structure. The absorbance and fluorescence excitation and emission spectra of the purified phycobiliproteins were identical to those previously shown for C-PC and APC. APC can be stored concentrated at 4 degrees C, frozen at -70 degrees C, or as a saturated ammonium sulfate precipitate, with no subunit dissociation or change in spectral properties. Moreover, APC has been conjugated to monoclonal and polyclonal antibodies for use in multicolor FACS analysis, with the conjugated antibody activity remaining stable for at least 2 years. Thus, this procedure is a simple, cost-effective method for preparing reagents for multicolor immunofluorescence and flow cytometry. The polypeptide composition of the phycobilisome, the major light-harvesting complex of prokaryotic cyanobacteria and certain eukaryotic algae, can be modulated by different light qualities in cyanobacteria exhibiting chromatic adaptation. We have identified genomic fragments encoding a cluster of phycobilisome polypeptides (phycobiliproteins) from the chromatically adapting cyanobacterium Fremyella diplosiphon using previously characterized DNA fragments of phycobiliprotein genes from the eukaryotic alga Cyanophora paradoxa and from F. diplosiphon. Characterization of two lambda-EMBL3 clones containing overlapping genomic fragments indicates that three sets of phycobiliprotein genes--the alpha- and beta-allophycocyanin genes plus two sets of alpha- and beta-phycocyanin genes--are clustered within 13 kilobases on the cyanobacterial genome and transcribed off the same strand. The gene order (alpha-allophycocyanin followed by beta-allophycocyanin and beta-phycocyanin followed by alpha-phycocyanin) appears to be a conserved arrangement found previously in a eukaryotic alga and another cyanobacterium. We have reported that one set of phycocyanin genes is transcribed as two abundant red light-induced mRNAs (1600 and 3800 bases). We now present data showing that the allophycocyanin genes and a second set of phycocyanin genes are transcribed into major mRNAs of 1400 and 1600 bases, respectively. These transcripts are present in RNA isolated from cultures grown in red and green light, although lower levels of the 1600-base phycocyanin transcript are present in cells grown in green light. Furthermore, a larger transcript of 1750 bases hybridizes to the allophycocyanin genes and may be a precursor to the 1400-base species. The genes encoding the alpha and beta subunits of allophycocyanin, phycocyanin and phycoerythrin from the red alga Aglaothamnion neglectum were isolated and characterized. While the operons containing the different phycobiliprotein genes are dispersed on the plastid genome, the genes encoding the alpha and beta subunits for each phycobiliprotein are contiguous. The beta subunit gene is 5' for both the phycocyanin and phycoerythrin operons, while the alpha subunit gene is 5' for the allophycocyanin operon. The amino acid sequences of A. neglectum phycobiliproteins, as deduced from the nucleotide sequences of the genes, are 65-85% identical to analogous proteins from other red algae and cyanobacteria. The conserved nature of the plastid-encoded red algal and cyanobacterial phycobiliprotein genes supports the proposed origin of red algal plastids from cyanobacterial endosymbionts. Many environmental factors effect phycobilisome biosynthesis. The effect of both nutrient availability and light quantity on the level of A. neglectum phycobiliprotein subunits and the mRNA species encoding those subunits is described. This report describes a feasibility study concerning the use of a visible diode laser for two important fluorescence applications in a flow cytometer. With a 3 mW 635 nm diode laser, we performed immunofluorescence measurements using the fluorophore allophycocyanin (APC). We have measured CD8 positive lymphocytes with a two-step labeling procedure and the resulting histograms showed good separation between the negative cells and the dim and the bright fluorescent subpopulations. As a second fluorescence application, we chose DNA analysis with the recently developed DNA/RNA stains TOTO-3 and TO-PRO-3. In our setup TO-PRO-3 yielded the best results with a CV of 3.4%. Our results indicate that a few milliwatts of 635 nm light from a visible diode laser is sufficient to do single color immunofluorescence measurements with allophycocyanin and DNA analysis with TO-PRO-3. The major advantages of using a diode laser in a flow cytometer are the small size, the low price, the high efficiency, and the long lifetime. R-phycoerythrin is the major light-harvesting pigment protein of most red algal phycobilisomes. It is composed of three pigmented polypeptide subunits, the alpha, beta, and gamma. While alpha and beta phycoerythrin subunits are each unique in the red alga Aglaothamnion neglectum, there are two different gamma subunits with distinct molecular masses. Both gamma subunits are pigmented by virtue of covalently attached linear tetrapyrroles. The amino acid sequence of one of the gamma subunits, as deduced from the nucleotide sequence of a cDNA clone, has no significant similarity to any known sequence in the data bases. This result is surprising, since the gamma subunit of phycoerythrin is thought to have a function that is similar to cyanobacterial linker polypeptides. The A. neglectum gamma subunit is synthesized as a 36-kDa precursor protein that is processed at the amino terminus to yield a 33-kDa mature protein. The amino-terminal extension was able to direct the pea small subunit of Rubisco into isolated pea chloroplasts. This result suggests that red algae transport proteins into the plastid by a mechanism similar to that of higher plants. There are significant changes in levels of mRNA encoding the gamma 33 subunit when A. neglectum is grown under different conditions of illumination and in nitrogen-deficient medium. These changes parallel those previously observed for transcripts encoding the alpha and beta phycoerythrin subunits. Hence, there may be coordinated expression of nuclear and plastid-encoded phycoerythrin subunit genes. Phycobilisomes of the unicellular marine cyanobacteria are unique in having rod substructures with two distinct phycoerythrins, PE I and PE II, with five and six bilins, respectively (Ong, L. J., and Glazer, A. N. (1991) J. Biol. Chem. 266, 9515-9527). The genes for the alpha and beta subunits of PE I, PE II, and phycocyanin, and that for the PE II-associated linker polypeptide, are clustered on a single 15-kilobase region of the genome of Synechococcus sp. WH8020. Complete sequencing of this region allowed definitive assignment of the positions of all bilin attachment sites in these phycobiliproteins. Twelve other open reading frames are closely associated with the structural genes specified above. Six are homologous to open reading frames adjacent to phycobiliprotein genes in other cyanobacteria and inferred to be involved in bilin addition. This is the largest number of open reading frames of this class known in any cyanobacterium. Another of the open reading frames has a short region of striking similarity to the active site sequence of a bovine protein-phosphotyrosine phosphatase. Phycoerythrin is a major light-harvesting pigment of red algae and cyanobacteria that is widely used as a fluorescent probe and analytical reagent. In this paper, B-phycoerythrin and R-phycocyanin in native state, from the red alga Porphyridium cruentum were obtained by an inexpensive and simple process. The best results of this purification procedure were scaled up by a factor of 13 to a large preparative level using an anionic chromatographic column of DEAE cellulose. Gradient elution with acetic acid-sodium acetate buffer (pH 5.5) was used. In these conditions both 32% of B-phycoerythrin and 12% of R-phycocyanin contained in the biomass of the microalgae was recovered. B-phycoerythrin was homogeneous as determined by sodium dodecyl sulfate-poly-acrylamide gel electrophoresis (SDS-PAGE), yielding three migrating bands corresponding to its three subunits, consistent with the (alpha beta)(6)gamma subunit composition characteristic of this biliprotein and the spectroscopic characterization of B-PE (UV-visible absorption and emission spectroscopy; steady-state and polarization fluorescence), is accompanied. Finally, a preliminary cost analysis of the recovery process is presented. B-Phycoerythrin (B-PE) is a major light-harvesting pigment of microalgae. Due to its high fluorescence efficiency and its intense and unique pink color, it is widely used as a fluorescent probe and analytical reagent as well as being employed as a natural dye in foods and cosmetics. Tedious methodologies for B-PE purification have been published. In this work we present a new, fast, preparative and scaleable two-step chromatographic method for B-PE purification from the red microalga Porphyridium cruentum. Initially, phycobiliproteins were released from the microalga cells by osmotic shock and captured by applying the centrifuged cell suspension to a column containing 74 ml Streamline-DEAE equilibrated with 50 mM acetic acid-sodium acetate buffer, pH 5.5, using expanded-bed adsorption chromatography at an upward flow of 200 cm h(-1). After adsorption, washing was carried out in the expanded-bed mode. Having removed unbound proteins and cellular debris, the bed was allowed to sediment and a B-PE-rich solution was eluted with a downward flow of the same 250 mM buffer. In order to obtain pure B-PE, we utilized conventional ion-exchange chromatography with a column of DEAE-cellulose loaded directly with the eluate from Streamline-DEAE and developed using a discontinuous gradient of acetic acid-sodium acetate buffer, pH 5.5. With this new methodology, 66% of B-PE contained in the biomass of the microalgae was recovered, a value significantly higher than those obtained following other methodologies. The B-PE purity was tested using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and spectroscopic characterization. C-Phycocyanin (C-PC), the major light harvesting biliprotein from Spirulina platensis is of greater importance because of its various biological and pharmacological properties. It is a water soluble, non-toxic fluorescent protein pigment with potent anti-oxidant, anti-inflammatory and anti-cancer properties. In the present study the effect of highly purified C-PC was tested on growth and multiplication of human chronic myeloid leukemia cell line (K562). The results indicate significant decrease (49%) in the proliferation of K562 cells treated with 50 microM C-PC up to 48 h. Further studies involving fluorescence and electron microscope revealed characteristic apoptotic features like cell shrinkage, membrane blebbing and nuclear condensation. Agarose electrophoresis of genomic DNA of cells treated with C-PC showed fragmentation pattern typical for apoptotic cells. Flow cytometric analysis of cells treated with 25 and 50 microM C-PC for 48 h showed 14.11 and 20.93% cells in sub-G0/G1 phase, respectively. C-PC treatment of K562 cells also resulted in release of cytochrome c into the cytosol and poly(ADP) ribose polymerase (PARP) cleavage. These studies also showed down regulation of anti-apoptotic Bcl-2 but without any changes in pro-apoptotic Bax and thereby tilting the Bcl-2/Bax ratio towards apoptosis. These effects of C-PC appear to be mediated through entry of C-PC into the cytosol by an unknown mechanism. The present study thus demonstrates that C-PC induces apoptosis in K562 cells by cytochrome c release from mitochondria into the cytosol, PARP cleavage and down regulation of Bcl-2. The aim of this study was to systematically examine the inhibitory mechanisms of C-phycocyanin (C-PC), one of the major phycobiliproteins of Spirulina platensis (a blue-green alga), in platelet activation. In this study, C-PC concentration-dependently (0.5-10 nM) inhibited platelet aggregation stimulated by agonists. C-PC (4 and 8 nM) inhibited intracellular Ca2+ mobilization and thromboxane A2 formation but not phosphoinositide breakdown stimulated by collagen (1 microg/mL) in human platelets. In addition, C-PC (4 and 8 nM) markedly increased levels of cyclic GMP and cyclic GMP-induced vasodilator-stimulated phosphoprotein (VASP) Ser(157) phosphorylation. Rapid phosphorylation of a platelet protein of Mw 47,000 (P47), a marker of protein kinase C activation, was triggered by phorbol-12,13-dibutyrate (150 nM). This phosphorylation was markedly inhibited by C-PC (4 and 8 nM). In addition, C-PC (4 and 8 nM) markedly reduced the electron spin resoce (ESR) signal intensity of hydroxyl radicals in collagen (1 microg/mL)-activated platelets. The present study reports on a novel and very potent (in omolar concentrations) antiplatelet agent, C-PC, which is involved in the following inhibitory pathways: (1) C-phycocyanin increases cyclic GMP/VASP Ser157 phosphorylation and subsequently inhibits protein kinase C activity, resulting in inhibition of both P47 phosphorylation and intracellular Ca2+ mobilization, and (2) C-PC may inhibit free radicals (such as hydroxyl radicals) released from activated platelets, which ultimately inhibits platelet aggregation. These results strongly indicate that C-PC appears to represent a novel and potential antiplatelet agent for treatment of arterial thromboembolism. R-phycoerythrin was isolated and purified from a red alga, Polysiphonia urceolata Grev, using Streamline column combined with ion-exchange chromatography or hydroxyapatite chromatography. The purity of R-phycoerythrin isolated by Streamline column was up to 1.66 and the yield of R-phycoerythrin could be as high as 0.68 mg/g frozen P. urceolata. All the eluates from Streamline column were divided into two equivalent parts, respectively. One part was pumped into the ion-exchange column loaded with Q-Sepharose and the other was applied to the adsorption column loaded with hydroxyapatite. The purities of R-phycoerythrin purified using these two methods were both up to 3.26, more than 3.2 the commonly accepted criterion. The yield of purified R-phycoerythrin from the ion-exchange chromatography was 0.40 mg/g frozen P. urceolata and that from the hydroxyapatite chromatography could reach 0.34 mg/g frozen P. urceolata. The purified protein had three absorption peaks at 498, 535, and 565 nm and displayed a fluorescence maximum at 580 nm, which was consistent with the typical spectrum of R-phycoerythrin. The purified R-PE was also identified with electrophoresis. Only one single protein band appeared on native-PAGE with silver staining. SDS-PAGE demonstrated the presence of one 20 kDa major subunit, and one low intensity band corresponding to 33 kDa subunit. The results indicate that using the expanded bed adsorption combined with ion-exchange chromatography or hydroxyapatite chromatography, R-phycoerythrin can be purified from frozen P. urceolata on large scale. Photosynthetic action spectra of several cyanobacteria show a peak at about 650 nm, the height of which is correlated with allophycocyanin content in the strains examined. Allophycocyanin harvests light more efficiently than do phycocyanin and phycoerythrin. The contribution of chlorophyll a absorption to photosynthetic activity is barely detectable in cells of normal pigment composition. Chlorophyll a becomes the major light-harvesting pigment in cells that have been physiologically depleted of phycobiliproteins. Antibodies raised against mixtures of phycobilisome polypeptides from the eukaryotic alga Cyanidium caldarium were used in an immunological screen to detect expression of phycobiliprotein genes in an Escherichia coli library containing segments of plastid (chloroplast, cyanelle) DNA from another eukaryotic alga, Cyanophora paradoxa. The four candidate clones obtained were mapped by restriction analysis and found to be overlapping. The clone with the smallest insert (1.4 kilobases) was partially sequenced and a coding region similar to the carboxyl terminus of the phycobiliprotein subunit beta-phycocyanin was found. The coding region for the beta-phycocyanin gene in C. paradoxa has been mapped to the small single copy region on the cyanelle genome, and its orientation has been determined. A short probe unique to a conserved chromophore binding site shared by at least two phycobiliprotein subunits has now been generated from the carboxyl terminus of the beta-phycocyanin gene. This probe may be useful in identifying specific phycobiliprotein subunit genes, beta-phycocyanin, beta-phycoerythrocyanin, and possibly beta-phycoerythrin, in other eukaryotic algae and in prokaryotic cyanobacteria. Phycocyanin--a major phycobiliprotein constitutively produced by many cyanobacteria--holds several promising applications in diagnostics, biomedical research, and therapeutics. This paper discusses a novel rapid method for the purification of cyanobacterial phycocyanin (C-PC) from Phormidium fragile using hydrophobic interaction chromatography. The protein was extracted and concentrated by grinding under liquid nitrogen and ammonium sulfate fractionation. C-PC was purified by single step hydrophobic interaction chromatography. Purified phycocyanin showed absorbance maximum (lambda(max)) at 624 nm. The criterion of purity (R) achieved was 4.52. Phycocyanin to phycoerythrin and phycocyanin to allophycocyanin purity ratio were 3.85 and 7.49, respectively. The purified protein showed a pI of 5.2 and has two subunits with molecular mass of 19 and 20 kDa each, corresponding to its highly reported alpha and beta subunits. The subunits of phycocyanin were confirmed by their bilin fluorescence using zinc assisted fluorescence enhancement technique. Intact C-PC was of 125 kDa as determined by HPLC, suggested the (alphabeta)(3) subunit assembly. Results obtained by this method in terms of purity, recovery, process time, simplicity, and efficacy are much better than previous methodologies. Purified phycocyanin was further scrutinized for its antioxidant capacity and judged against five non-enzymatic antioxidants by FRAP assay. Phycocyanin is a major protein produced by cyanobacteria, but very few phycocyanin-producing strains have been reported. In the present study, response surface methodology (RSM) involving a central composite design for four factors was successfully employed to optimize medium components for increased production of phycocyanin from Phormidium ceylanicum. The production of phycocyanin and interactions between sodium nitrate, calcium chloride, trace metal mix and citric acid stock were investigated and modeled. Under optimized condition P. ceylanicum was able to give 2.3-fold increase in phycocyanin production in comparison to commonly used BG 11 medium in 32 days. We have demonstrated the extraction, purification and characterization of C-phycocyanin using novel method based on filtration and single step chromatography. The protein was extracted by repeated freeze-thaw cycles and the crude extract was filtered and concentrated in stirred ultrafiltration cell (UFC). The UFC concentrate was then subjected to a single ion exchange chromatographic step. A purity ratio of 4.15 was achieved from a starting value of 1.05. The recovery efficiency of C-phycocyanin from crude extract was 63.50%. The purity was checked by electrophoresis and UV-Vis spectroscopy. Unicellular cryptophyte algae employ antenna proteins with phycobilin chromophores in their photosynthetic machinery. The mechanism of light harvesting in these organisms is significantly different than the energy funneling processes in phycobilisomes utilized by cyanobacteria and red algae. One of the most striking features of cryptophytes is the location of the water-soluble phycobiliproteins, which are contained within the intrathylakoid spaces and are not on the stromal side of the lamellae as in the red algae and cyanobacteria. Studies of mobility of phycobiliproteins at the lumenal side of the thylakoid membranes and how their diffusional behavior may influence the energy funneling steps in light harvesting are reported. Confocal microscopy and fluorescence recovery after photobleaching (FRAP) are used to measure the diffusion coefficient of phycoerythrin 545 (PE545), the primary light harvesting protein of Rhodomonas CS24, in vivo. It is concluded that the diffusion of PE545 in the lumen is inhibited, suggesting possible membrane association or aggregation as a potential source of mobility hindrance. Spirulina platensis produces nutraceutical product C-phycocyanin (C-PC) and simultaneously mitigates CO2 emissions during its growth. Using a designed flat-type photobioreactor, the S. platensis biomass production was markedly enhanced, leading to a CO2 removal rate and a biomass concentration of 0.23 g/L/d and 2.25 g/L, respectively. The cell growth, CO2 fixation rate and C-PC production of S. platensis were investigated when it was cultivated under different irradiation conditions. As the light intensity increased from 100 to 700 μmol/m(2)/s, the overall biomass productivity, CO2 consumption rate and maximal C-PC productivity increased significantly to 0.74, 1.53 and 0.11 g/L/d, respectively. After determining the suitable light intensity, the nitrogen concentration was also adjusted to further enhance the performance of CO2 fixation and C-PC production. The results show that with an optimal nitrogen concentration of 0.045 M, the CO2 consumption rate and maximal C-PC productivity were further increased to 1.58 and 0.13 g/L/d, respectively. An extensive range of pigments including phycobiliproteins are present in algae. C-phycocyanin (C-PC), a phycobiliprotein, is one of the key pigments of Spirulina, a microalgae used in many countries as a dietary supplement. Algal pigments have massive commercial value as natural colorants in nutraceutical, cosmetics, and pharmaceutical industries, besides their health benefits. At present, increasing awareness of harmful effects of synthetic compounds and inclination of community towards the usage of natural products have led to the exploitation of microalgae as a source of natural pigments/colors. This review describes recent findings about the sources and production of C-PC, with emphasis on specific techniques for extraction and purification, along with potential industrial applications in diagnostics, foods, cosmetics, and pharmaceutical industries. Phycobilisomes are aggregates of light-harvesting proteins attached to the stroma side of the thylakoid membranes of the cyanobacteria (blue-green algae) and red algae. The water-soluble phycobiliproteins, of which there are three major groups, tetrapyrrole chromophores covalently bound to apoprotein. Several additional protiens are found within the phycobilisome and serve to link the phycobiliproteins to each other in an ordered fashion and also to attach the phycobilisome to the thylakoid membrane. Excitation energy absorbed by phycoerythrin is transferred through phycocyanin to allophycocyanin with an efficiency approximating 100%. This pathway of excitation energy transfer, directly confirmed by time-resolved spectroscopic measurements, has been incorporated into models describing the ultrastructure of the phycobilisome. The model for the most typical type of phycobilisome describes an allophycocyanin-containing core composed of three cylinders arranged so that their longitudinal axes are parallel and their ends form a triangle. Attached to this core are six rod structures which contain phycocyanin proximal to the core and phycoerythrin distal to the core. The axes of these rods are perpendicular to the longitudinal axis of the core. This arrangement ensures a very efficient transfer of energy. The association of phycoerythrin and phycocyanin within the rods and the attachment of the rods to the core and the core to the thylakoid require the presence of several 'linker' polypeptides. It is recently possible to assemble functionally and structurally intact phycobilisomes in vitro from separated components as well as to reassociate phycobilisomes with stripped thylakoids. Understanding of the biosynthesis and in vivo assembly of phycobilisomes will be greatly aided by the current advances in molecular genetics, as exemplified by recent identification of several genes encoding phycobilisome components.Combined ultrastructural, biochemical and biophysical approaches to the study of cyanobacterial and red algal cells and isolated phycobilisome-thylakoid fractions are leading to a clearer understanding of the phycobilisome-thylakoid structural interactions, energy transfer to the reaction centers and regulation of excitation energy distribution. However, compared to our current knowledge concerning the structural and functional organization of the isolated phycobilisome, this research area is relatively unexplored.

Is PLK2 involved in alpha-synuclein phosphorylation in the nervous system?

Polo-like kinase 2 (PLK2) phosphorylates alpha-synuclein at serine 129 in the central nervous system.

α-Synuclein (α-syn) is the major component of pathological inclusions characteristic of several neurodegenerative disorders, such as Parkinson's disease. The major posttranslational modification of α-syn is phosphorylation at S129, and previous studies estimate that approximately 90% of α-syn in proteinaceous, pathological inclusions is phosphorylated at this site. α-Syn can be phosphorylated by polo-like kinases (PLKs) 1-3 and casein kinases (CK) 1 and 2; however, the kinases associated with the hyperphosphorylation of aggregated α-syn are still under debate. Using a high-efficiency cellular model of α-syn aggregate formation, we found that selective inhibitors for CK2 and PLKs each partially inhibited S129 phosphorylation of soluble (nonaggregated) α-syn, but only PLK inhibitors modestly attenuated the phosphorylation of aggregated α-syn. In addition, none of the kinase inhibitors used had a substantial effect on the propensity of α-syn to aggregate. Overexpression of all PLKs promoted robust phosphorylation of soluble α-syn, but none altered the propensity of α-syn to aggregate. Overexpression of only PLK2 increased phosphorylation of aggregated α-syn at S129, which likely is due to increased phosphorylation of soluble α-syn, which then was incorporated into aggregates. Overexpression of PLK1 and treatment with BI2536 resulted in a significant reduction of phosphorylated, aggregated α-syn protein, beyond that of BI2536 treatment alone. These studies suggest that phosphorylation of α-syn is independent of α-syn aggregate formation, that PLK1 is involved in the phosphorylation of aggregated α-syn at S129 in this system, and that mechanisms resulting in hyperphosphorylation of aggregated α-syn appear to be independent of those responsible for the phosphorylation of soluble α-syn. Intense research efforts are currently directed at elucidating the etiology of Parkinson's disease (PD). One approach that has begun to shed light on the PD pathogenic pathways is the identification of disease genes through genetic linkage or association studies. These studies have revealed that several kinases may be involved in PD, as some PD genes encode kinases themselves while other PD genes are found in the same cellular pathways as kinases. Two of these kinases stand out as potential drug targets for novel PD therapy, namely leucine rich repeat kinase 2 (LRRK2) and the alpha-synuclein (α-syn) phosphorylating polo-like kinase 2 (PLK2). Indeed, both α- syn and LRRK2 show genetic linkage as well as genetic association with PD, indicating their relevance to a large number of PD cases. Also, due to the domit mode of α-syn and LRRK2 inheritance and based on current knowledge of LRRK2 and α-syn phosphorylation by PLK2, inhibition of LRRK2 and PLK2 may constitute a potential therapy for PD. Here we discuss the function of these kinases as well as progress in their validation as drug targets for the treatment of PD. Polo-like kinase-2 (Plk-2) has been implicated as the domit kinase involved in the phosphorylation of α-synuclein in Lewy bodies, which are one of the hallmarks of Parkinson's disease neuropathology. Potent, selective, brain-penetrant inhibitors of Plk-2 were obtained from a structure-guided drug discovery approach driven by the first reported Plk-2-inhibitor complexes. The best of these compounds showed excellent isoform and kinome-wide selectivity, with physicochemical properties sufficient to interrogate the role of Plk-2 inhibition in vivo. One such compound significantly decreased phosphorylation of α-synuclein in rat brain upon oral administration and represents a useful probe for future studies of this therapeutic avenue toward the potential treatment of Parkinson's disease. α-Synuclein is the major component of Lewy bodies. α-Synuclein phosphorylated at Ser 129 (Phospho-α-Syn) is the most common synuclein modification observed in Parkinson's disease pathology and transgenic animal models. Polo-like kinase 2 (PLK2) was previously proposed as an important kinase in α-synuclein phosphorylation at Ser129. To better understand the role of PLK2 in α-synuclein phosphorylation in vivo, we further evaluated the effect of PLK2 genetic knockdown and pharmacological inhibition on Phospho-α-Syn levels in different brain regions of PLK2 knockout (KO), heterozygous (Het) and wild-type (WT) mice. Whereas PLK2 knockdown had no effect on Total-α-synuclein brain levels, it resulted in a gene-dosage dependent, albeit incomplete, reduction of endogenous Phospho-α-Syn levels in all brain regions investigated. No compensatory induction of other α-synuclein kinases (PLK3, casein kinase-2, G-protein-coupled receptor kinase 5 (GRK5) and GRK6) was observed at the mRNA level in the PLK2 KO mouse brain. To determine whether increased activity of another PLK family member is responsible for the residual Phospho-α-Syn levels in the PLK2 KO mouse brain, the pan-PLK inhibitor BI 2536 was tested in PLK2 KO mice. Whereas BI 2536 reduced Phospho-α-Syn levels in WT mice, it did not further reduce the residual endogenous Phospho-α-Syn levels in PLK2 KO and Het mice, suggesting that a kinase other than PLK1-3 accounts for the remaining PLK inhibitor-resistant pool in the mouse brain. Moreover, PLK3 KO in mice had no effect on both Total- and Phospho-α-Syn brain levels. These results support a significant role for a PLK kinase in phosphorylating α-synuclein at Ser129 in the brain, and suggest that PLK2 is responsible for this activity under physiological conditions.

In which kingdom do microsporidia belong, according to their current classification scheme?

Traditionally, microsporidia were considered as protozoans, but recently they have been reclassified as the earliest-diverging clade of sequenced fungi. Microsporidia are a diverse group of obligate, intracellular, eukaryotic, spore-forming parasites; they are ubiquitous fungi, with genomes that have undergone a strong reduction.

Microsporidia are obligate intracellular parasites that were thought to be an ancient eukaryotic lineage based on molecular phylogenies using ribosomal RNA and translation elongation factors. However, this ancient origin of microsporidia has been contested recently, as several other molecular phylogenies suggest that microsporidia are closely related to fungi. Most of the protein trees that place microsporidia with fungi are not well sampled, however, and it is impossible to resolve whether microsporidia evolved from a fungus or from a protistan relative of fungi. We have sequenced beta-tubulins from 3 microsporidia, 4 chytrid fungi, and 12 zygomycete fungi, expanding the representation of beta-tubulin to include all four fungal divisions and a wide diversity of microsporidia. In phylogenetic trees including these new sequences, the overall topology of the fungal beta-tubulins generally matched the expected relationships among the four fungal divisions, although the zygomycetes were polyphyletic in some analyses. The microsporidia consistently fell within this fungal diversification, and not as a sister group to fungi. Overall, beta-tubulin phylogeny suggests that microsporidia evolved from a fungus sometime after the divergence of chytrids. We also found that chytrid alpha- and beta-tubulins are much less divergent than are tubulins from other fungi or microsporidia. In trees in which the only fungal representatives were the chytrids, microsporidia still branched with fungi (i.e., with chytrids), suggesting that the affiliation between microsporidian and fungal tubulins is not an artifact of long-branch attraction. The ancestors of fungi are believed to be simple aquatic forms with flagellated spores, similar to members of the extant phylum Chytridiomycota (chytrids). Current classifications assume that chytrids form an early-diverging clade within the kingdom Fungi and imply a single loss of the spore flagellum, leading to the diversification of terrestrial fungi. Here we develop phylogenetic hypotheses for Fungi using data from six gene regions and nearly 200 species. Our results indicate that there may have been at least four independent losses of the flagellum in the kingdom Fungi. These losses of swimming spores coincided with the evolution of new mechanisms of spore dispersal, such as aerial dispersal in mycelial groups and polar tube eversion in the microsporidia (unicellular forms that lack mitochondria). The enigmatic microsporidia seem to be derived from an endoparasitic chytrid ancestor similar to Rozella allomycis, on the earliest diverging branch of the fungal phylogenetic tree. A comprehensive phylogenetic classification of the kingdom Fungi is proposed, with reference to recent molecular phylogenetic analyses, and with input from diverse members of the fungal taxonomic community. The classification includes 195 taxa, down to the level of order, of which 16 are described or validated here: Dikarya subkingdom nov.; Chytridiomycota, Neocallimastigomycota phyla nov.; Monoblepharidomycetes, Neocallimastigomycetes class. nov.; Eurotiomycetidae, Lecanoromycetidae, Mycocaliciomycetidae subclass. nov.; Acarosporales, Corticiales, Baeomycetales, Candelariales, Gloeophyllales, Melanosporales, Trechisporales, Umbilicariales ords. nov. The clade containing Ascomycota and Basidiomycota is classified as subkingdom Dikarya, reflecting the putative synapomorphy of dikaryotic hyphae. The most dramatic shifts in the classification relative to previous works concern the groups that have traditionally been included in the Chytridiomycota and Zygomycota. The Chytridiomycota is retained in a restricted sense, with Blastocladiomycota and Neocallimastigomycota representing segregate phyla of flagellated Fungi. Taxa traditionally placed in Zygomycota are distributed among Glomeromycota and several subphyla incertae sedis, including Mucoromycotina, Entomophthoromycotina, Kickxellomycotina, and Zoopagomycotina. Microsporidia are included in the Fungi, but no further subdivision of the group is proposed. Several genera of 'basal' Fungi of uncertain position are not placed in any higher taxa, including Basidiobolus, Caulochytrium, Olpidium, and Rozella. BACKGROUND: Microsporidia are obligate intracellular, eukaryotic pathogens that infect a wide range of animals from nematodes to humans, and in some cases, protists. The preponderance of evidence as to the origin of the microsporidia reveals a close relationship with the fungi, either within the kingdom or as a sister group to it. Recent phylogenetic studies and gene order analysis suggest that microsporidia share a particularly close evolutionary relationship with the zygomycetes. METHODOLOGY/PRINCIPAL FINDINGS: Here we expanded this analysis and also examined a putative sex-locus for variability between microsporidian populations. Whole genome inspection reveals a unique syntenic gene pair (RPS9-RPL21) present in the vast majority of fungi and the microsporidians but not in other eukaryotic lineages. Two other unique gene fusions (glutamyl-prolyl tRNA synthetase and ubiquitin-ribosomal subunit S30) that are present in metazoans, choanoflagellates, and filasterean opisthokonts are unfused in the fungi and microsporidians. One locus previously found to be conserved in many microsporidian genomes is similar to the sex locus of zygomycetes in gene order and architecture. Both sex-related and sex loci harbor TPT, HMG, and RNA helicase genes forming a syntenic gene cluster. We sequenced and analyzed the sex-related locus in 11 different Encephalitozoon cuniculi isolates and the sibling species E. intestinalis (3 isolates) and E. hellem (1 isolate). There was no evidence for an idiomorphic sex-related locus in this Encephalitozoon species sample. According to sequence-based phylogenetic analyses, the TPT and RNA helicase genes flanking the HMG genes are paralogous rather than orthologous between zygomycetes and microsporidians. CONCLUSION/SIGNIFICANCE: The unique genomic hallmarks between microsporidia and fungi are independent of sequence based phylogenetic comparisons and further contribute to define the borders of the fungal kingdom and support the classification of microsporidia as unusual derived fungi. And the sex/sex-related loci appear to have been subject to frequent gene conversion and translocations in microsporidia and zygomycetes. Microsporidia are a large diverse group of intracellular parasites now considered as fungi. They are particularly prevalent in fish and are recognized as important opportunistic parasites in humans. Although the mode of transmission of microsporidia has not been fully clarified, the consumption and manipulation of infected fish may be a risk factor for humans. Comparative analysis of rDNA sequence revealed that the microsporidians used in the present study had 99-100% identity with anglerfish microsporidians of the genus Spraguea and very low identity with microsporidians that infect humans. Microsporidian spores were exposed to different physical and chemical treatments: freezing at -20°C for 24-78 h, heating at 60°C for 5-15 min, microwaving at 700 W, 2.45 GHz for 15-60s, and treatment with ethanol at concentrations of between 1 and 70% for 15 min. The viability of the spores after each treatment was evaluated by two methods: a) haemocytometer counts, measuring the extrusion of the polar filament in control and treated spores, and b) a fluorometric method, testing the membrane integrity by propidium iodide exclusion. The results of both methods were concordant. Spores were inactivated by freezing at -20°C for more than 48 h, by heating to 60°C for 10 min and by microwaving at 750 W, for 20s. Exposure to 70% ethanol for 15 min also inactivated microsporidian spores. The results suggest that both freezing and heating are effective treatments for destroying microsporidian spores in European white anglerfish, and that 70% ethanol could be used by fish processors to disinfect their hands and the utensils used in processing fish. The fluorometric method can be used as an alternative to haemocytometer counts in disinfection studies aimed at establishing strategies for inactivating and reducing the viability and the potential infectivity of microsporidians present in fish or in the environment. Microsporidia are unicellular fungi that are obligate endoparasites. Although nematodes are one of the most abundant and diverse animal groups, the only confirmed report of microsporidian infection was that of the "nematode killer" (Nematocida parisii). N. parisii was isolated from a wild Caenorhabditis sp. and causes an acute and lethal intestinal infection in a lab strain of Caenorhabditis elegans. We set out to characterize a microsporidian infection in a wild nematode to determine whether the infection pattern of N. parisii in the lab is typical of microsporidian infections in nematodes. We describe a novel microsporidian species named Sporanauta perivermis (marine spore of roundworms) and characterize its infection in its natural host, the free-living marine nematode Odontophora rectangula. S. perivermis is not closely related to N. parisii and differs strikingly in all aspects of infection. Examination by transmission electron microscopy (TEM) revealed that the infection was localized in the hypodermal and muscle tissues only and did not involve the intestines. Fluorescent in situ hybridization (FISH) confirmed infection in the muscle and hypodermis, and surprisingly, it also revealed that the parasite infects O. rectangula eggs, suggesting a vertical mode of transmission. Our observations highlight the importance of studying parasites in their natural hosts and indicate that not all nematode-infecting microsporidia are "nematode killers"; instead, microsporidiosis can be more versatile and chronic in the wild. Microsporidia are ubiquitous fungi with genomes that have undergone a strong reduction to the extreme cases of Encephalitozoon cuniculi and Encephalitozoon intestinalis. Genetic variability within species of the Encephalitozoon genus has been reported, with most of the studies based on the internal transcribed spacer (ITS) of the rDNA. However, in contrast to the picture of E. cuniculi and Encephalitozoon hellem, where different strains have been identified, no genetic variability has yet been observed in E. intestinalis. We have analysed tandem repeats included in putative coding sequences which could be used as polymorphic markers in E. intestinalis. Eight candidate loci (M2, M2A, M3, M5, M7, M7A, M8 and PTP1) were established and 9 E. intestinalis cultured strains from North America, South America and Europe were analysed. M2, M7 and PTP1 nucleotide sequences were identical among the different strains and the GenBank sequence. In contrast, we observed variants in 4 markers (M2A, M3, M7A and M8) which did not correspond to their respective reference sequences. The most noticeable finding was that with the M5 marker two genotypes were defined among the different strains studied, demonstrating genotypic variability of E. intestinalis. Although the diversity described is certainly not high, which can be explained by a lower chance of genetic variability in its minimal genome, we have demonstrated that polymorphisms actually exist in E. intestinalis. Epidemiological studies using this genetic marker should now be conducted to elucidate the genetic variability in E. intestinalis and improve our knowledge of the epidemiology of this microsporidia. Microorganisms of the microsporidia group are obligated intracellular protozoa that belong to the phylum Microspora; currently they are considered to be related or belong to the fungi reign. It is considered an opportunistic infection in humans, and 14 species belonging to 8 different genera have been described. Immunocompromized patients such as those infected with human immunodeficiency virus (HIV), also HIV serum-negative asymptomatic patients, with poor hygienic conditions, and recipients of bone marrow or solid organ transplantation are susceptible to develop deinfection. Sixty transplanted patients with renal microsporidia infection have been reported worldwide. The aim of this paper is to inform about the 2nd case of kidney transplant and microsporidia infection documented in Mexico. Fungal species play extremely important roles in ecosystems. Clustered at the base of the fungal kingdom are Microsporidia, a group of obligate intracellular eukaryotes infecting multiple animal lineages. Because of their large host spectrum and their implications in host population regulation, they influence food webs, and accordingly, ecosystem structure and function. Unfortunately, their ecological role is not well understood. Present also as highly resistant spores in the environment, their characterisation requires special attention. Different techniques based on direct isolation and/or molecular approaches can be considered to elucidate their role in the ecosystems, but integrating environmental and genomic data (for example, genome architecture, core genome, transcriptional and translational signals) is crucial to better understand the diversity and adaptive capacities of Microsporidia. Here, we review the current status of Microsporidia in trophic networks; the various genomics tools that could be used to ensure identification and evaluate diversity and abundance of these organisms; and how these tools could be used to explore the microsporidian life cycle in different environments. Our understanding of the evolution of these widespread parasites is currently impaired by limited sampling, and we have no doubt witnessed but a small subset of their diversity.

What is the inheritance pattern of Emery-Dreifuss muscular dystrophy?

The inheritance pattern of Emery-Dreifuss muscular dystrophy (EDMD) can be X-linked, autosomal dominant or autosomal recessive.

The authors relate a unique observation of the familial form of proximal myodystrophy with early contractures and maligt course. The primary character of muscular injury was confirmed on electromyography. The data of electrocardiography and echocardiography attested to the presence in the patients of the signs of cardiomyopathy. Since the disease was diagnosed in 3 brothers, the X-coupled recessive type of its inheritance is assumed. An opinion is advanced that the described form is a clinical variety of Emery-Dreyfus myodystrophy. A young woman with humeroperoneal muscular dystrophy and contractures received a heart transplant for a severe dilated cardiomyopathy. Cardiac histopathology consisted of myocyte hypertrophy, interstitial fibrosis, and nuclear hyperchromaticity without mitochondrial abnormalities. Myopathy and heart disease were not clinically evident in her family, although three relatives had unexplained shortened Achilles tendons without weakness. Tendon contractures may be a partial expression of this myopathic disorder, suggesting an autosomal domit inheritance with variable penetrance. A muscular dystrophy clinically similar to that of the Emery-Dreifuss (EDMD) type can thus occur in women. Rather than the cardiac arrhythmias typical of EDMD, a dilated cardiomyopathy may occur and present with severe congestive heart failure. This is the first report of cardiac transplantation in such a case. The first German family with autosomal domit Emery-Dreifuss syndrome (EDS) is described, with electrophysiologic and myopathologic results providing evidence of a primary neurogenic disease. According to classification of the scapulo peroneal syndrome without cardiomyopathy, we conclude that there are two variants of EDS: one myopathic, the other neurogenic in origin. Therefore, the term Emery-Dreifuss muscular dystrophy should be avoided. Instead, each case of EDS should be classified as myopathic or neurogenic with X chromosome recessive or autosomal domit inheritance. A young adult male is described with muscular dystrophy of probable X-linked recessive inheritance. An onset of muscle weakness in late adolescence was preceded by contractures of the neck and elbows dating back to childhood. The distribution of muscle weakness was proximal in the upper limbs and both proximal and distal in the lower. The mixed pattern of muscle involvement in the legs favours the view that cases of Emery-Dreifuss muscular dystrophy with proximal weakness in both the upper and lower limbs and X-linked scapuloperoneal muscular dystrophy represent the same disorder. A muscle biopsy in the present case showed unique appearances. Emery-Dreifuss muscular dystrophy is a syndrome with five salient features: early and unusual contractures; humeroperoneal muscle wasting; the slow progression of weakness, beginning in childhood; cardiac conduction defects; and X-linked inheritance. We present two cases and detail other reports with a similar constellation of findings with apparent autosomal domit inheritance. We postulate separate genetic disorders with similar phenotypic expression. A woman with early-onset, slowly progressive, humeroperoneal muscle weakness had marked restriction of neck flexion with contracture at the elbows. She developed exertional dyspnea at age 25, atrial fibrillation with slow ventricular rate was discovered, and a cardiac pacemaker was implanted. Her father had a similar disorder. There is at least one other report of autosomal domit transmission of this clinical picture, which had previously only been reported as Emery-Dreifuss muscular dystrophy with X-linked recessive inheritance. Thus, more than one mode of inheritance is possible for this unusual and distinctive form of muscular dystrophy. Two familial and 2 sporadic cases of Emery-Dreifuss syndrome are reported. One family presented a rare autosomal domit variant of Emery-Dreifuss muscular dystrophy, another with X-linked recessive inheritance showed unusual intrafamilial variability. One of sporadic cases closely resembled rigid spine syndrome, the other was clinically intermediate between Emery-Dreifuss muscular dystrophy and rigid spine syndrome, showing that they are not distinct disorders. Emery-Dreifuss muscular dystrophy (EMD) is characterised by (1) early contractures of the Achilles tendons, elbows, and postcervical muscles, (2) slowly progressive muscle wasting and weakness with a predomitly humeroperoneal distribution in the early stages, and (3) cardiomyopathy with conduction defects and risk of sudden death. Inheritance is usually X linked recessive but can be autosomal domit. Family linkage studies have mapped X linked EMD to the distal long arm of the X chromosome but precise genetic localisation has been hampered by the rarity of this condition. We report three new families with X linked Emery-Dreifuss muscular dystrophy studied with DNA markers from Xq27-qter and three previously published families typed for additional markers. No recombination was observed with the red/green cone pigment locus, RGCP (lod score, Z = 2.46), the factor VIII coagulant gene locus, F8C (Z = 6.39), or with DXS115 (Z = 4.94). Two recombits were observed which mapped EMD distal to DXS15 (DX13) and DXS52 (St14) respectively. Multipoint linkage analysis gave odds exceeding 200:1 for EMD being distal to these markers. A multipoint analysis incorporating published data gave the map cen-DXS304-9cM-DXS15-3cM-DXS52-2 cM-(RGCP,EMD)-3cM-F8C-2cM-DXS115 with odds of 120:1 in favour of a location for EMD between DXS52 and F8C as compared to the next best position distal to F8C. OBJECTIVE: To describe the clinical and histopathologic picture of a childhood-onset, severe variant of scapuloperoneal MD with rigidity of the spine. BACKGROUND: Rigidity of the spine is a feature of numerous syndromes, including X-linked Emery-Dreifuss MD, Bethlem myopathy, and the rigid spine syndrome. These are, however, relatively static or very slowly progressive neuromuscular disorders, usually associated with preserved ambulation into adult life. PATIENTS AND METHODS: Five unrelated children (three boys and two girls) presented in the first 2 years of life with poor neck control, waddling gait, and frequent falls. Early wasting of the distal leg muscles, biceps, triceps, and neck muscles was noted in all patients, and all had contractures and severe rigidity of the spine. The condition progressed rapidly, and all patients lost ambulation before the age of 8 years. Cardiac function was normal in all. RESULTS: Creatine kinase was moderately elevated in all, and muscle biopsy specimens showed nonspecific dystrophic changes with normal expression of dystrophin, the sarcoglycans, and laminin alpha2, alpha5, beta1, and gamma1 chains. Emerin expression was normal in two of the boys whose tissue was available for study. CONCLUSIONS: The distribution of weakness, wasting, and contractures of the patients described resembled Emery-Dreifuss MD, but the rapid progression of weakness and contractures and the involvement of both sexes together with normal emerin expression suggest that this form is not X-linked Emery-Dreifuss MD. We suggest that these patients represent a severe MD characterized by early onset distal wasting and severe rigidity of the spine, with probable autosomal recessive inheritance. Emery-Dreifuss muscular dystrophy is characterized by the clinical triad of early onset contractures of elbows, Achilles tendons and spine, wasting and weakness with a predomitly humero-peroneal distribution and life-threatening cardiac conduction defects and/or cardiomyopathy. Two main types of inheritance have been described: the X-linked form is caused by mutations in the STA gene on locus Xq28 and the gene for the autosomal domit form (LMNA gene) has been localized on chromosome 1q11-q23. Recently, mutations in this LMNA gene have been also found to be responsible for the less frequent autosomal recessive form of the disease. Although all forms share a similar clinical presentation, some differences appear to exist between them as has been described recently in a large number of patients. We present the first documented Spanish family genetically confirmed to have autosomal domit Emery-Dreifuss muscular dystrophy. Clinical, pathological and genetic data are described. We emphasize the difficulties in diagnosis, especially in sporadic cases or young patients in whom the clinical picture is not completely established. The Charcot-Marie-Tooth (CMT) disorders comprise a group of clinically and genetically heterogeneous hereditary motor and sensory neuropathies, which are mainly characterized by muscle weakness and wasting, foot deformities, and electrophysiological, as well as histological, changes. A subtype, CMT2, is defined by a slight or absent reduction of nerve-conduction velocities together with the loss of large myelinated fibers and axonal degeneration. CMT2 phenotypes are also characterized by a large genetic heterogeneity, although only two genes---NF-L and KIF1Bbeta---have been identified to date. Homozygosity mapping in inbred Algerian families with autosomal recessive CMT2 (AR-CMT2) provided evidence of linkage to chromosome 1q21.2-q21.3 in two families (Zmax=4.14). All patients shared a common homozygous ancestral haplotype that was suggestive of a founder mutation as the cause of the phenotype. A unique homozygous mutation in LMNA (which encodes lamin A/C, a component of the nuclear envelope) was identified in all affected members and in additional patients with CMT2 from a third, unrelated family. Ultrastructural exploration of sciatic nerves of LMNA null (i.e., -/-) mice was performed and revealed a strong reduction of axon density, axonal enlargement, and the presence of nonmyelinated axons, all of which were highly similar to the phenotypes of human peripheral axonopathies. The finding of site-specific amino acid substitutions in limb-girdle muscular dystrophy type 1B, autosomal domit Emery-Dreifuss muscular dystrophy, dilated cardiomyopathy type 1A, autosomal domit partial lipodystrophy, and, now, AR-CMT2 suggests the existence of distinct functional domains in lamin A/C that are essential for the maintece and integrity of different cell lineages. To our knowledge, this report constitutes the first evidence of the recessive inheritance of a mutation that causes CMT2; additionally, we suggest that mutations in LMNA may also be the cause of the genetically overlapping disorder CMT2B1. A 32-year-old woman is described as having the following characteristics of Emery-Dreifuss muscular dystrophy: humeroperoneal muscular atrophy and weakness, neck and elbow contractures with sinus bradycardia, first-degree atrioventricular block, and dilated cardiomyopathy. The biopsy specimen of skeletal muscle showed dystrophic character; a cardiac endomyocardial biopsy specimen showed adipose tissue infiltration and deposition of antihuman IgG. Emery-Dreifuss muscular dystrophy is an X-linked recessive myopathy. The patient had no familial background of the disease. This patient might have a sporadic inheritance pattern with severe cardiac involvement. Individuals with the same genetic disorder often show remarkable differences in clinical severity, a finding generally attributed to the genetic background. We identified two patients with genetically proven Emery-Dreifuss muscular dystrophy (EDMD) who followed an unusual course and had uncommon clinicopathological findings. We hypothesized digenic inheritance and looked for additional molecular explanations. Mutations in additional separate genes were identified in both patients. The first patient was a member of a family with molecularly proven X-linked EDMD. However, the clinical features were unusually severe for this condition in the propositus: he presented at 2.5 years with severe proximal weakness and markedly elevated serum creatine kinase. Muscle weakness rapidly progressed, leading to loss of independent ambulation by the age of 12. In addition, the patient developed cardiac conduction system disease requiring pacing at the age of 11 and severe dilated cardiomyopathy in the early teens. Despite pacing, he had several syncopal episodes attributed to ventricular dysrhythmias. As these resemble the cardiac features of patients with the autosomal domit variant of EDMD, we examined the lamin A/C gene, identifying a de-novo mutation in the propositus. The second patient had a cardioskeletal myopathy, similar to his mother who had died more than 20 years previously. Because of the domit family history, a laminopathy was suspected and a mutation in exon 11 of the LMNA gene was identified. This mutation, however, was not present in his mother, but instead, surprisingly, was identified in his virtually asymptomatic father. Unusual accumulations of desmin found in the cardiac muscle of the propositus prompted us to examine the desmin gene in this patient, and in so doing, we identified a desmin mutation, in addition to the LMNA mutation in the propositus. These cases suggest that separate mutations in related proteins that are believed to interact, or that represent different parts of a presumed functional pathway, may synergistically contribute to disease severity in autosomal domit EDMD. Furthermore, digenic inheritance may well contribute to the clinical severity of many other neuromuscular disorders. The Emery-Dreifuss muscular dystrophy is a form of muscular dystrophy that frequently presents early contractures and cardiac conduction defects, caused by emerin deficiency in the inner nuclear membrane of the muscular fibers. A 19-years-old man it presented muscle weakness and hypotrophy in the proximal upper and lower limbs, dysphagia and early contractures in elbows and ankles, with familiar history compatible with X-linked inheritance form. The investigation showed increased serum creatinekinase levels electrocardiogram had a first degree atrioventricular block and right bundle branch block normal electromyography and nerve conduction study muscle biopsy disclosed myopathic characteristics and nuclear protein immunohystochemical analysis showed deficiency of emerin. The clinical and genetics manifestations, laboratorial and electromyography changes, as well as, the study of the pattern of inheritance for genetic counseling are discussed. INTRODUCTION: Atrial fibrillation (AF) is a heritable disorder with male predilection, suggesting a sex chromosome defect in certain patients. Loss-of-function truncation mutations in EMD, encoding the nuclear membrane protein emerin, cause X-linked Emery-Dreifuss muscular dystrophy (EDMD) characterized by localized contractures and skeletal myopathy in adolescence, sinus node dysfunction (SND) in early adulthood, and atrial fibrillation as a variably associated trait. This study sought to identify the genetic basis for male-restricted, nonsyndromic sinus node dysfunction and AF in a multigenerational family. METHODS AND RESULTS: Genealogical and medical records, and DNA samples, were obtained. Progressive SND and AF occurred in four males related through maternal lineages, consistent with X-linked inheritance. Skeletal myopathy was absent, even at advanced ages. Targeted X chromosome genotyping mapped the disease locus to Xq28, implicating EMD as a positional candidate gene. DNA sequencing revealed hemizygosity for an in-frame 3-bp deletion in EMD (Lys37del) in affected males, disrupting a residue within the LEM binding domain critical for nuclear assembly but leaving the remainder of the protein intact. Buccal epithelial cell staining with emerin antibody demonstrated near-total functional loss of emerin. Female relatives underwent prospective electrocardiographic and genetic testing. Those heterozygous for Lys37del had approximately 50-70% emerin-positive nuclei and variable degrees of paroxysmal supraventricular arrhythmia. CONCLUSIONS: Mutation of EMD can underlie X-linked familial AF. Lys37del is associated with epithelial cell emerin deficiency, as in EDMD, yet it causes electrical atriomyopathy in the absence of skeletal muscle disease. Targeted genetic testing of EMD should be considered in patients with SND-associated AF and/or family history suggesting X-linked inheritance. Emery-Dreifuss myopathy can be associated with a cardiomyopathy and cardiac dysrhythmias. The inheritance pattern of Emery-Dreifuss muscular dystrophy (EDMD) is X linked, whereas EDMD2 is autosomal domit. EDMD2 is caused by lamin A/C gene (LMNA) mutations that produce alterations in the lamin proteins that are integral to nuclear and cell integrity. A 53-year-old man was brought to us with a right internal carotid artery dissection. Detailed work-up of the patient and family members revealed some unusual features, and genetic sequencing of the LMNA gene was undertaken. A novel mutation was identified in two of the samples sent for analysis. We present the first Indian family of EDMD2 with familial dilated cardiomyopathy and cardiac dysrhythmias in whom LMNA gene sequencing was performed. A novel mutation was identified and additional unusual clinical features were described.

What is the mechanism of action of anticoagulant medication Dabigatran?

Dabigatran is orally administered, reverisble direct and competetive inhibitor of both free and bouded thrombin.

The focus of this review is the evolving field of antithrombotic drug therapy for stroke prevention in patients with atrial fibrillation (AF). The current standard of therapy includes warfarin, acenocoumarol and phenprocoumon which have proven efficacy by reducing stroke by 68% against placebo. However, a narrow therapeutic index, wide variation in metabolism, and numerous food and drug interactions have limited their clinical application to only 50% of the indicated population. Newer agents such as direct thrombin inhibitors, factor Xa inhibitors, factor IX inhibitors, tissue factor inhibitors and a novel vitamin K antagonist are being developed to overcome the limitations of current agents. The direct thrombin inhibitor dabigatran is farthest along in development. Further clinical trial testing, and eventual incorporation into clinical practice will depend on safety, efficacy and cost. Development of a novel vitamin K antagonist with better INR control will challenge the newer mechanistic agents in their quest to replace the existing vitamin K antagonists. Till then, the large unfilled gap to replace conventional agents remains open. This review will assess all these agents, and compare their mechanism of action, stage of development and pharmacologic profile. Apixaban is an oral, direct and highly selective factor Xa (FXa) inhibitor in late-stage clinical development. This study evaluated the in vitro effect of apixaban on human platelet aggregation induced by thrombin derived via the extrinsic pathway. Direct inhibitors of FXa (rivaroxaban), FVIIa (BMS-593214), thrombin (dabigatran, argatroban) and FXIa (BMS-262084) were included for comparison. Citrated human platelets-rich plasma (PRP) was treated with 50 mg/ml corn trypsin inhibitor (to block the contact factor pathway) and 3 mM H-Gly-Pro-Arg-Pro-OH-AcOH (to prevent fibrin polymerisation). Human tissue factor (TF) (Innovin; dilution 1:1,000 to 1:1,500) plus 7.5 mM CaCl2 was added to PRP pre-incubated with vehicle or increasing concentrations of inhibitors. The TF-induced platelet aggregation was measured by optical aggregometry. TF produced 85 +/- 3% aggregation of human platelets in the vehicle-treated group (n=10). Apixaban and other factor inhibitors, except the FXIa inhibitor, inhibited TF-induced platelet aggregation with IC50 (nM) values as follows: 4 +/- 1 (apixaban), 8 +/- 2 (rivaroxaban), 13 +/- 1 (BMS-593214), 46 +/- 1 (dabigatran) and 79 +/- 1 (argatroban). BMS-262084 (IC50 = 2.8 nM vs. human FXIa) had no effect on TF-induced platelet aggregation at 10 microM. These inhibitors at 10 microM had no effect on platelet aggregation induced by ADP and collagen, as expected from their mechanism of action. This study demonstrates that inhibition of thrombin generation by blocking upstream proteases (FVIIa and FXa) in the blood coagulation cascade is as effective as direct thrombin inhibition in preventing TF-induced platelet aggregation. Under these experimental conditions, a FXIa inhibitor did not prevent TF-induced platelet aggregation. Although results of some phase III clinical trials of new oral anticoagulants are now known, it is important to understand the mechanisms of their actions. These new agents exert their anticoagulant effect via direct inhibition of a single Factor within the coagulation cascade (such as Factor Xa or thrombin). Rivaroxaban--the first oral, direct Factor Xa inhibitor--is a small-molecule oxazolidinone derivative that binds directly and reversibly to Factor Xa via the S1 and S4 pockets. Rivaroxaban competitively inhibits Factor Xa and is more than 10,000-fold more selective for Factor Xa than other related serine proteases, and it does not require cofactors (such as antithrombin) to exert its anticoagulant effect. Unlike indirect Factor Xa inhibitors, rivaroxaban inhibits both free and clot-bound Factor Xa, as well as prothrombinase activity, thereby prolonging clotting times. Dabigatran etexilate is a direct thrombin inhibitor that inhibits both free and fibrin-bound thrombin. Although the mechanism of action differs between the direct Factor Xa and direct thrombin inhibitors, phase III studies of these new agents confirmed that both Factor Xa and thrombin are viable anticoagulation targets. Rivaroxaban is an oral, direct Factor Xa inhibitor approved in the European Union and several other countries for the prevention of venous thromboembolism in adult patients undergoing elective hip or knee replacement surgery and is in advanced clinical development for the treatment of thromboembolic disorders. Its mechanism of action is antithrombin independent and differs from that of other anticoagulants, such as warfarin (a vitamin K antagonist), enoxaparin (an indirect thrombin/Factor Xa inhibitor) and dabigatran (a direct thrombin inhibitor). A blood coagulation computer model has been developed, based on several published models and preclinical and clinical data. Unlike previous models, the current model takes into account both the intrinsic and extrinsic pathways of the coagulation cascade, and possesses some unique features, including a blood flow component and a portfolio of drug action mechanisms. This study aimed to use the model to compare the mechanism of action of rivaroxaban with that of warfarin, and to evaluate the efficacy and safety of different rivaroxaban doses with other anticoagulants included in the model. Rather than reproducing known standard clinical measurements, such as the prothrombin time and activated partial thromboplastin time clotting tests, the anticoagulant benchmarking was based on a simulation of physiologically plausible clotting scenarios. Compared with warfarin, rivaroxaban showed a favourable sensitivity for tissue factor concentration inducing clotting, and a steep concentration-effect relationship, rapidly flattening towards higher inhibitor concentrations, both suggesting a broad therapeutic window. The predicted dosing window is highly accordant with the final dose recommendation based upon extensive clinical studies. Atrial fibrillation (AF) is the most common cardiac rhythm disorder and a major risk factor for stroke. For more than 60 years, warfarin has been the only approved anticoagulant for prevention of stroke in patients with AF. Although highly effective, it has many limitations that make its use difficult. Therefore, several novel anticoagulants are under development to overcome the limitations of warfarin, and some of these have entered phase III clinical trials. Dabigatran is an oral, reversible direct thrombin inhibitor approved in Europe and in several other countries for the prevention of venous thromboembolism after elective knee and hip replacement surgery. It has also been approved in the United States and Japan for the prevention of stroke and systemic embolism in patients with nonvalvular AF. In this review, the mechanism of action and pharmacological properties of new anticoagulants are described in detail, and the correct use of dabigatran in clinical practice is discussed. For the last 60 years warfarin has been the cornerstone for chronic anticoagulation in prevention of ischemic strokes and systemic embolization. Warfarin therapy has several limitations including frequent monitoring and various food and significant drug interactions, which make it a less than ideal chronic oral anticoagulant. The continued search for safe, effective, medications with predictable pharmacokinetic profiles has led to newer alternatives. Dabigatran is a potent reversible, competitive direct thrombin inhibitor which is available as the prodrug, Dabigatran etexilate. It was first approved in Europe and recently in October 2010, the US food and drug administration (FDA) has approved the use of this novel oral anticoagulation for prevention of stroke in those with non valvular atrial fibrillation. This review will cover the chemical structure, mechanism of action, pharmacokinetic profile, clinical trials, dosage, clinical implication and adverse effects of dabigatran. The effect of the oral direct activated factor X (factor Xa) inhibitor apixaban on tissue factor-induced thrombin generation in human plasma was investigated in vitro using the calibrated automated thrombogram (CAT) method and compared with the oral direct factor Xa inhibitor rivaroxaban and the direct thrombin inhibitor dabigatran. Pooled citrated, anticoagulated, platelet-poor human plasma was spiked with apixaban, rivaroxaban, or dabigatran at concentrations of 0.01 to 10 μM. The inhibitory potencies of the compounds were quantified by 5 CAT parameters: the control thrombin lag time (LT) and time to thrombin peak (TTP) for the doubling of inhibitor concentration (IC2x); and the control endogenous thrombin potential (ETP), thrombin peak, and maximum rate of thrombin generation (Vmax) for the inhibitor concentration, which inhibited 50% (IC50). The inhibitors modified CAT concentration dependently. Their inhibitory potencies, expressed as IC2x LT, IC2x TTP, IC50 ETP, IC50 peak thrombin, and IC50 Vmax, were as follows: 0.10 ± 0.01, 0.19 ± 0.02, 0.65 ± 0.11, 0.089 ± 0.019, and 0.049 ± 0.007 μM for apixaban; 0.049 ± 0.007, 0.070 ± 0.009, 0.43 ± 0.07, 0.048 ± 0.008, and 0.022 ± 0.005 μM for rivaroxaban; and 0.063 ± 0.019, 0.18 ± 0.06, 0.50 ± 0.08, 0.55 ± 0.06, and 0.57 ± 0.27 μM for dabigatran. In summary, apixaban, rivaroxaban, and dabigatran have similar potencies in the prolongation of LT and TTP. The CAT parameters that are related to the rate of thrombin generation during the propagation phase (ie, peak thrombin and Vmax) are more sensitive to activities of apixaban and rivaroxaban than dabigatran. The ETP is the least sensitive parameter for measuring the activities of these inhibitors. Recombit activated factor VII at 5 and 50 μg/mL reversed the anticoagulant effects of apixaban more at 0.2 μM than at 2 μM. Our study suggests that the CAT method is a sensitive assay to monitor the pharmacodynamic and pharmacokinetic properties of apixaban, rivaroxaban, and dabigatran, and may provide insight into the mechanism of action of these inhibitors. Recombit activated factor VII may have some potential to reverse the anticoagulant effects of apixaban in vitro.

What is the effect of a defective CLN3 gene?

Mutations in the CLN3 gene, which encodes a lysosomal membrane protein, are responsible for the neurodegenerative disorder juvenile Batten disease.

Batten disease (juvenile-onset neuronal ceroid lipofuscinosis, JNCL), the most common neurodegenerative disorder of childhood, is caused by mutations in a recently identified gene ( CLN3 ) localized to chromosome 16p11.2-12.1. To elucidate the biosynthesis and localization of the CLN3 protein, we expressed CLN3 cDNA in COS-1 and HeLa cell lines. In vitro translation, immunoprecipitation and Western blotting analyses detected an approximately 43 kDa polypeptide. Pulse-chase experiments indicated that the CLN3 protein is synthesized as an N -glycosylated single-chain polypeptide, which was not detected in growth medium. Confocal immunofluorescence microscopy revealed that the CLN3 protein is localized to the lysosomal compartment. These results provide evidence that Batten disease can be classified as a member of lysosomal diseases. 1. In order to investigate the biological function of the human CLN3 gene that is defective in Batten disease, we created a yeast strain by PCR-targeted disruption of the yeast gene (YHC3), which is a homologue of the human CLN3 gene. 2. The phenotypic characterization revealed that the yhc3 delta mutants are more sensitive to combined heat and alkaline stress than the wild-type strains as determined by inhibition of cell proliferation. 3. This suggests that the yhc3 delta mutant is a good model to investigate the biological function of human CLN3 gene in mammalian cells and to understand the pathophysiology of juvenile Batten disease. During brain development, excess neurons that are formed die by apoptosis. cln3 was recently identified as the gene defective in juvenile Batten disease, an inherited neurodegenerative disease of childhood. In this disease, neurons die by apoptosis. Overexpression of this gene increases survival of human NT2 neuronal precursor cells. We, therefore, hypothesized that cln3 may be present in developing neurons and may play an important role in regulating the developmental process. NT2 neuronal cells were induced to develop into mature neurons. We evaluated cln3 expression by reverse transcription PCR and immunohistochemistry over a 7-wk period of differentiation. Also, cln3 expression was characterized in neonatal rat brain during the first week of life (P-1, P0, P4, and P8) and at P30. cln3 was differentially expressed during neuronal development into nondividing post-mitotic neurons. The greatest expression was noted during wk 6 and then dropped to predifferentiation levels during wk 7. cln3 expression was detected in all the rat brain developmental stages evaluated. The greatest expression was seen at P0 and was double compared with the other stages. We conclude that cln3 is present during critical periods of neuronal cell differentiation and brain development. As cln3 is antiapoptotic, we hypothesize that cln3 plays an important role in regulating brain development. These findings may have implications for identifying strategies aimed at neuroprotection and neuronal survival during development. The endosomal/lysosomal transmembrane protein CLN3 is mutated in the Batten disease (juvenile neuronal ceroid lipofuscinosis, JNCL). However, the molecular mechanism of JNCL pathogenesis and the exact function of the CLN3 protein have remained unclear. Previous studies have shown that deletion of BTN1, the yeast orthologue of CLN3, leads to increased expression of BTN2. BTN2 encodes Btn2p, a proposed homologue to a novel microtubule-binding protein Hook1, which regulates endocytosis in Drosophila. We analysed here the putative interconnection between CLN3 and Hook1 in the mammalian cells and discovered that overexpression of human CLN3 induces aggregation of Hook1 protein, potentially by mediating its dissociation from the microtubules. Using in vitro binding assay we were able to demonstrate a weak interaction between Hook1 and the cytoplasmic segments of CLN3. We also found receptor-mediated endocytosis to be defective in CLN3-deficient JNCL fibroblasts, connecting CLN3, Hook1 and endocytosis in the mammalian system. Moreover, co-immunoprecipitation experiments showed that Hook1 physically interacts with endocytic Rab7, Rab9 and Rab11, hence delineating a manifold role for mammalian Hook1 in membrane trafficking events. These novel interactions between the microtubule-binding Hook1 and the large family of Rab GTPases also suggest a link between CLN3 function, microtubule cytoskeleton and endocytic membrane trafficking. The vacuolar H(+)-ATPase (V-ATPase) along with ion channels and transporters maintains vacuolar pH. V-ATPase ATP hydrolysis is coupled with proton transport and establishes an electrochemical gradient between the cytosol and vacuolar lumen for coupled transport of metabolites. Btn1p, the yeast homolog to human CLN3 that is defective in Batten disease, localizes to the vacuole. We previously reported that Btn1p is required for vacuolar pH maintece and ATP-dependent vacuolar arginine transport. We report that extracellular pH alters both V-ATPase activity and proton transport into the vacuole of wild-type Saccharomyces cerevisiae. V-ATPase activity is modulated through the assembly and disassembly of the V(0) and V(1) V-ATPase subunits located in the vacuolar membrane and on the cytosolic side of the vacuolar membrane, respectively. V-ATPase assembly is increased in yeast cells grown in high extracellular pH. In addition, at elevated extracellular pH, S. cerevisiae lacking BTN1 (btn1-Delta), have decreased V-ATPase activity while proton transport into the vacuole remains similar to that for wild type. Thus, coupling of V-ATPase activity and proton transport in btn1-Delta is altered. We show that down-regulation of V-ATPase activity compensates the vacuolar pH imbalance for btn1-Delta at early growth phases. We therefore propose that Btn1p is required for tight regulation of vacuolar pH to maintain the vacuolar luminal content and optimal activity of this organelle and that disruption in Btn1p function leads to a modulation of V-ATPase activity to maintain cellular pH homeostasis and vacuolar luminal content. Juvenile neuronal ceroid-lipofuscinosis (JNCL) or Batten/Spielmeyer-Vogt-Sjogren disease (OMIM #204200) is one of a group of nine clinically related inherited neurodegenerative disorders (CLN1-9). JNCL results from mutations in CLN3 on chromosome 16p12.1. The neuronal loss in Batten disease has been shown to be due to a combination of apoptosis and autophagy suggesting that CLN3P, the defective protein, may have an anti-neuronal death function. PANDER (PANcreatic-DERived factor) is a novel cytokine that was recently cloned from pancreatic islet cells. PANDER is specifically expressed in the pancreatic islets, small intestine, testis, prostate, and neurons of the central nervous system, and has been demonstrated to induce apoptosis. In this study, we over-expressed CLN3P in SH-SY5Y neuroblastoma cells and monitored the effects on PANDER-induced apoptosis. CLN3P significantly increased the survival rate of the SH-SY5Y cells in this system. This study provides additional evidence that the function of CLN3P is related to preventing neuronal apoptosis. Juvenile neuronal ceroid lipofuscinosis (Batten disease) is a neurodegenerative disorder caused by defective function of the lysosomal membrane glycoprotein CLN3. The activity of the lysosomal acid phosphatase (LAP/ACP2) was found to be significantly increased in the cerebellum and brain stem of Cln3-targeted mice during the early stages of postnatal life. Histochemical localization studies revealed an increased LAP/ACP2 staining intensity in neurons of the cerebral cortex of 48-week-old Cln3-targeted mice as compared with controls. Additionally, the expression of another lysosomal membrane protein LAMP-2 was increased in all brain areas. Knockdown of CLN3 expression in HeLa cells by RNA interference also resulted in increased LAP/ACP2 and LAMP-2 expression. Finally in fibroblasts of two juvenile neuronal ceroid lipofuscinosis patients elevated levels of LAP/ACP2 were found. Both activation of gene transcription and increased protein half-life appear to contribute to increased LAP/ACP2 protein expression in CLN3-deficient cells. The data suggest that lysosomal dysfunction and accumulation of storage material require increased biogenesis of LAP/ACP2 and LAMP-2 positive membranes which makes LAP/ACP2 suitable as biomarker of Batten disease.

Which genes are regulated by TRalpha2 in the heart?

ARB1, ARB2, TAK1, p38, TRalpha1

Thyroid hormone governs a diverse repertoire of physiological functions through receptors encoded in the receptor genes alpha and beta, which each generate variant proteins. In mammals, the alpha gene generates, in addition to the normal receptor TRalpha1, a non-hormone-binding variant TRalpha2 whose exact function is unclear. Here, we present the phenotype associated with the targeted ablation of TRalpha2 expression. Selective ablation of TRalpha2 resulted in an inevitable, concomitant overexpression of TRalpha1. Both TRalpha2 +/- and -/- mice show a complex phenotype with low levels of free T3 and free T4, and have inappropriately normal levels of TSH. The thyroid glands exhibit mild morphological signs of dysfunction and respond poorly to TSH, suggesting that the genetic changes affect the ability of the gland to release thyroid hormones. However, the phenotype of the mutant mice also has features of hyperthyroidism, including decreased body weight, elevated heart rate, and a raised body temperature. Furthermore, TRalpha2-/- and TRalpha2+/- mice are obese and exhibit skeletal alterations, associated with a late-onset growth retardation. The results thus suggest that the overexpression of TRalpha1 and the concomitant decrease in TRalpha2 expression lead to a mixed hyper- and hypothyroid phenotype, dependent on the tissue studied. The phenotypes suggest that the balance of TRalpha1:TRalpha2 expressed from the TRalpha gene provides an additional level of tuning the control of growth and homeostasis in mammalian species. An altered thyroid hormone profile has been reported in patients with congestive heart failure. However, information regarding the status of thyroid hormone receptors in human failing cardiomyocytes is lacking. Therefore the expression of thyroid hormone and beta-adrenergic receptors was investigated in human ventricular cardiomyocytes isolated from patients with end-stage heart failure (FM, n=12), or from tentative donors (C, n=4). The expression of thyroid (TRalpha1, and TRbeta1) and beta-adrenergic receptors (ARB1 and ARB2) was measured at both the gene, and at the protein level. In FM the reduced mRNA expression of ARB1 (p<0.05, -37%) and ARB2 (p<0.05, -42%) was associated with a reduction of the messenger for TRalpha1 (p<0.05, -85%) and TRalpha2 (p<0.05, -73%). These findings were confirmed at the protein level for ARB1, ARB2 and TRalpha1. These data reveal that in human heart failure the reduction of beta-adrenergic receptors is associated with reduced expression of both TRalpha1 and TRalpha2 isoforms of thyroid hormone receptors.

Is insulin-like growth factor-I (IGF-I) able to affect tendon protein synthesis in classic Ehlers-Danlos syndrome patients?

Tendon protein synthesis rate in classic Ehlers-Danlos patients can be stimulated with insulin-like growth factor-I

The classic form of Ehlers-Danlos syndrome (cEDS) is an inherited connective tissue disorder, where mutations in type V collagen-encoding genes result in abnormal collagen fibrils. Thus the cEDS patients have pathological connective tissue morphology and low stiffness, but the rate of connective tissue protein turnover is unknown. We investigated whether cEDS affected the protein synthesis rate in skin and tendon, and whether this could be stimulated in tendon tissue with insulin-like growth factor-I (IGF-I). Five patients with cEDS and 10 healthy, matched controls (CTRL) were included. One patellar tendon of each participant was injected with 0.1 ml IGF-I (Increlex, Ipsen, 10 mg/ml) and the contralateral tendon with 0.1 ml isotonic saline as control. The injections were performed at both 24 and 6 h prior to tissue sampling. The fractional synthesis rate (FSR) of proteins in skin and tendon was measured with the stable isotope technique using a flood-primed continuous infusion over 6 h. After the infusion one skin biopsy and two tendon biopsies (one from each patellar tendon) were obtained. We found similar baseline FSR values in skin and tendon in the cEDS patients and controls [skin: 0.005 ± 0.002 (cEDS) and 0.007 ± 0.002 (CTRL); tendon: 0.008 ± 0.001 (cEDS) and 0.009 ± 0.002 (CTRL) %/h, mean ± SE]. IGF-I injections significantly increased FSR values in cEDS patients but not in controls (delta values: cEDS 0.007 ± 0.002, CTRL 0.001 ± 0.001%/h). In conclusion, baseline protein synthesis rates in connective tissue appeared normal in cEDS patients, and the patients responded with an increased tendon protein synthesis rate to IGF-I injections.

List available methods for transmembrane protein topology prediction.

HMMpTM, MetaTM, Philius, HMM_RA, HMMTOP, MEMSAT3, HMM-TM, TMHMM, Phobius and SignalP.

The HMMTOP transmembrane topology prediction server predicts both the localization of helical transmembrane segments and the topology of transmembrane proteins. Recently, several improvements have been introduced to the original method. Now, the user is allowed to submit additional information about segment localization to enhance the prediction power. This option improves the prediction accuracy as well as helps the interpretation of experimental results, i.e. in epitope insertion experiments. AVAILABILITY: HMMTOP 2.0 is freely available to non-commercial users at http://www.enzim.hu/hmmtop. Source code is also available upon request to academic users. An inherent problem in transmembrane protein topology prediction and signal peptide prediction is the high similarity between the hydrophobic regions of a transmembrane helix and that of a signal peptide, leading to cross-reaction between the two types of predictions. To improve predictions further, it is therefore important to make a predictor that aims to discriminate between the two classes. In addition, topology information can be gained when successfully predicting a signal peptide leading a transmembrane protein since it dictates that the N terminus of the mature protein must be on the non-cytoplasmic side of the membrane. Here, we present Phobius, a combined transmembrane protein topology and signal peptide predictor. The predictor is based on a hidden Markov model (HMM) that models the different sequence regions of a signal peptide and the different regions of a transmembrane protein in a series of interconnected states. Training was done on a newly assembled and curated dataset. Compared to TMHMM and SignalP, errors coming from cross-prediction between transmembrane segments and signal peptides were reduced substantially by Phobius. False classifications of signal peptides were reduced from 26.1% to 3.9% and false classifications of transmembrane helices were reduced from 19.0% to 7.7%. Phobius was applied to the proteomes of Homo sapiens and Escherichia coli. Here we also noted a drastic reduction of false classifications compared to TMHMM/SignalP, suggesting that Phobius is well suited for whole-genome annotation of signal peptides and transmembrane regions. The method is available at as well as at Transmembrane proteins affect vital cellular functions and pathogenesis, and are a focus of drug design. It is difficult to obtain diffraction quality crystals to study transmembrane protein structure. Computational tools for transmembrane protein topology prediction fill in the gap between the abundance of transmembrane proteins and the scarcity of known membrane protein structures. Their prediction accuracy is still inadequate: TMHMM, the current state-of-the-art method, has less than 52% accuracy in topology prediction on one set of transmembrane proteins of known topology. Based on the observation that there are functional domains that occur preferentially internal or external to the membrane, we have extended the model of TMHMM to incorporate functional domains, using a probabilistic approach originally developed for computational gene finding. Our extension is better than TMHMM in predicting the topology of transmembrane proteins. As prediction of functional domain improves, our system's prediction accuracy will likely improve as well. BACKGROUND: Hidden Markov Models (HMMs) have been extensively used in computational molecular biology, for modelling protein and nucleic acid sequences. In many applications, such as transmembrane protein topology prediction, the incorporation of limited amount of information regarding the topology, arising from biochemical experiments, has been proved a very useful strategy that increased remarkably the performance of even the top-scoring methods. However, no clear and formal explanation of the algorithms that retains the probabilistic interpretation of the models has been presented so far in the literature. RESULTS: We present here, a simple method that allows incorporation of prior topological information concerning the sequences at hand, while at the same time the HMMs retain their full probabilistic interpretation in terms of conditional probabilities. We present modifications to the standard Forward and Backward algorithms of HMMs and we also show explicitly, how reliable predictions may arise by these modifications, using all the algorithms currently available for decoding HMMs. A similar procedure may be used in the training procedure, aiming at optimizing the labels of the HMM's classes, especially in cases such as transmembrane proteins where the labels of the membrane-spanning segments are inherently misplaced. We present an application of this approach developing a method to predict the transmembrane regions of alpha-helical membrane proteins, trained on crystallographically solved data. We show that this method compares well against already established algorithms presented in the literature, and it is extremely useful in practical applications. CONCLUSION: The algorithms presented here, are easily implemented in any kind of a Hidden Markov Model, whereas the prediction method (HMM-TM) is freely available for academic users at http://bioinformatics.biol.uoa.gr/HMM-TM, offering the most advanced decoding options currently available. MOTIVATION: Many important biological processes such as cell signaling, transport of membrane-impermeable molecules, cell-cell communication, cell recognition and cell adhesion are mediated by membrane proteins. Unfortunately, as these proteins are not water soluble, it is extremely hard to experimentally determine their structure. Therefore, improved methods for predicting the structure of these proteins are vital in biological research. In order to improve transmembrane topology prediction, we evaluate the combined use of both integrated signal peptide prediction and evolutionary information in a single algorithm. RESULTS: A new method (MEMSAT3) for predicting transmembrane protein topology from sequence profiles is described and benchmarked with full cross-validation on a standard data set of 184 transmembrane proteins. The method is found to predict both the correct topology and the locations of transmembrane segments for 80% of the test set. This compares with accuracies of 62-72% for other popular methods on the same benchmark. By using a second neural network specifically to discriminate transmembrane from globular proteins, a very low overall false positive rate (0.5%) can also be achieved in detecting transmembrane proteins. AVAILABILITY: An implementation of the described method is available both as a web server (http://www.psipred.net) and as downloadable source code from http://bioinf.cs.ucl.ac.uk/memsat. Both the server and source code files are free to non-commercial users. Benchmark and training data are also available from http://bioinf.cs.ucl.ac.uk/memsat. BACKGROUND: Alpha-helical transmembrane (TM) proteins are involved in a wide range of important biological processes such as cell signaling, transport of membrane-impermeable molecules, cell-cell communication, cell recognition and cell adhesion. Many are also prime drug targets, and it has been estimated that more than half of all drugs currently on the market target membrane proteins. However, due to the experimental difficulties involved in obtaining high quality crystals, this class of protein is severely under-represented in structural databases. In the absence of structural data, sequence-based prediction methods allow TM protein topology to be investigated. RESULTS: We present a support vector machine-based (SVM) TM protein topology predictor that integrates both signal peptide and re-entrant helix prediction, benchmarked with full cross-validation on a novel data set of 131 sequences with known crystal structures. The method achieves topology prediction accuracy of 89%, while signal peptides and re-entrant helices are predicted with 93% and 44% accuracy respectively. An additional SVM trained to discriminate between globular and TM proteins detected zero false positives, with a low false negative rate of 0.4%. We present the results of applying these tools to a number of complete genomes. Source code, data sets and a web server are freely available from http://bioinf.cs.ucl.ac.uk/psipred/. CONCLUSION: The high accuracy of TM topology prediction which includes detection of both signal peptides and re-entrant helices, combined with the ability to effectively discriminate between TM and globular proteins, make this method ideally suited to whole genome annotation of alpha-helical transmembrane proteins. alpha-helical transmembrane (TM) proteins play important and diverse functional roles in cells. The ability to predict the topology of these proteins is important for identifying functional sites and inferring function of membrane proteins. This paper presents a Hidden Markov Model (referred to as HMM_RA) that can predict the topology of alpha-helical transmembrane proteins with improved performance. HMM_RA adopts the same structure as the HMMTOP method, which has five modules: inside loop, inside helix tail, membrane helix, outside helix tail and outside loop. Each module consists of one or multiple states. HMM_RA allows using reduced alphabets to encode protein sequences. Thus, each state of HMM_RA is associated with n emission probabilities, where n is the size of the reduced alphabet set. Direct comparisons using two standard data sets show that HMM_RA consistently outperforms HMMTOP and TMHMM in topology prediction. Specifically, on a high-quality data set of 83 proteins, HMM_RA outperforms HMMTOP by up to 7.6% in topology accuracy and 6.4% in alpha-helices location accuracy. On the same data set, HMM_RA outperforms TMHMM by up to 6.4% in topology accuracy and 2.9% in location accuracy. Comparison also shows that HMM_RA achieves comparable performance as Phobius, a recently published method.

Does GC content vary markedly within a given isochore?

Isochores are relatively long regions with a relatively homogeneous GC content, and with rather sharp boundaries with neighboring isochores. The base composition, and thus the GC content may differ between different isochores, but is more or less consistent within a given isochore.

The most deviant isochore pattern within mammals was found in rat and mouse; most other mammals possess a different kind of isochore organization called the "general pattern." However, isochore patterns remain largely unknown in rodents other than mouse and rat. To investigate the taxonomic distribution of isochore patterns in rodents, we sequenced the nuclear gene LCAT (lecithin:cholesterol acyltransferase) from 17 rodents species (bringing the total of LCAT sequences in rodent to 19) and compared their GC contents at third codon positions and in introns. We also analyzed an extensive sequence database from rodents other than rat and mouse. All murid LCAT sequences are much poorer in GC than all nonrodent LCAT sequences, and the hamster sequence database shows exactly the same isochore pattern as rat and mouse. Thus, all murids share the same special isochore pattern--GC homogenization. LCAT sequences are GC-poor in hystricomorphs too, but the guinea pig sequence database indicates that large changes in GC content occur without an overall modification of the isochore pattern. This novel mode of isochore evolution is called GC reordering. LCAT sequences also show that the evolution of isochores in sciurids and glirids is nonconservative in comparison with that in nonrodents. Thus, at least two novel patterns of isochore evolution were found. No rodent investigated to date shared the general mammalian pattern. The human genome is divided into isochores, large stretches (>>300 kb) of genomic DNA with more or less consistent GC content. Mutational/neutralist and selectionist models have been put forward to explain their existence. A major criticism of the mutational models is that they cannot account for the higher GC content at fourfold-redundant silent sites within exons (GC4) than in flanking introns (GCi). Indeed, it has been asserted that it is hard to envisage a mutational bias explanation, as it is difficult to see how repair enzymes might act differently in exons and their flanking introns. However, this rejection, we note, ignores the effects of transposable elements (TEs), which are a major component of introns and tend to cause them to have a GC content different from (usually lower than) that dictated by point mutational processes alone. As TEs tend not to insert at the extremities of introns, this model predicts that GC content at the extremities of introns should be more like that at GC4 than are the intronic interiors. This we show to be true. The model also correctly predicts that small introns should have a composition more like that at GC4 than large introns. We conclude that the logic of the previous rejection of neutralist models is unsafe. GC level distributions of a species' nuclear genome, or of its compositional fractions, encode key information on structural and functional properties of the genome and on its evolution. They can be calculated either from absorbance profiles of the DNA in CsCl density gradients at sedimentation equilibrium, or by scanning long contigs of largely sequenced genomes. In the present study, we address the quantitative characterization of the compositional heterogeneity of genomes, as measured by the GC distributions of fixed-length fragments. Special attention is given to mammalian genomes, since their compartmentalization into isochores implies two levels of heterogeneity, intra-isochore (local) and inter-isochore (global). This partitioning is a natural one, since large-scale compositional properties vary much more among isochores than within them. Intra-isochore GC distributions become roughly Gaussian for long fragments, and their standard deviations decrease only slowly with increasing fragment length, unlike random sequences. This effect can be explained by 'long-range' correlations, often overlooked, that are present along isochores. Three statistical/mathematical analyses are carried out on isochore sequences: spectral analysis, analysis of variance, and segmentation analysis. Spectral analysis shows that there are GC content fluctuations at different length scales in isochore sequences. The analysis of variance shows that the null hypothesis (the mean value of a group of GC contents remains the same along the sequence) may or may not be rejected for an isochore sequence, depending on the subwindow sizes at which GC contents are sampled, and the window size within which group members are defined. The segmentation analysis shows that there are stronger indications of GC content changes at isochore borders than within an isochore. These analyses support the notion of isochore sequences, but reject the assumption that isochore sequences are homogeneous at the base level. An isochore sequence may pass a homogeneity test when GC content fluctuations at smaller length scales are ignored or averaged out. The distribution of the G+C content in the mouse genome has been studied using a windowless technique. We have found that: (i). Abrupt variations of the G+C content from a GC-rich region to a GC-poor region, and vice versa, occur frequently at some sites along the sequence of the mouse genome. (ii). Long domains with relatively homogeneous G+C content (isochores) exist, which usually have sharp boundaries. Consequently, 28 isochores longer than 1 Mb have been identified in the mouse genome. A homogeneity index was used to quantify the variations of the G+C content within isochores. The precise boundaries, sizes, and G+C contents of these isochores have been determined. The windowless technique for the G+C content computation was also used to analyze the DNA sequence containing the mouse MHC region, which has a GC-poor isochore. This isochore is located at the central part of the sequence with boundaries at 468459 and 812716 bp, where the sequence is extended from the centromeric end to the telomeric end. In addition, the analysis of a segment of the rat genome shows that the rat genome also has clear isochore structures. The human genome is composed of long stretches of DNA with distinct GC contents, called isochores or GC-content domains. A boundary between two GC-content domains in the human NF1 gene region is also a boundary between domains of early- and late-replicating sequences and of regions with high and low recombination frequencies. The perfect conservation of the GC-content distribution in this region between human and mouse demonstrates that GC-content stabilizing forces must act regionally on a fine scale at this locus. To further elucidate the nature of these forces, we report here on the spectrum of human SNPs and base pair substitutions between human and chimpanzee. The results show that the mutation rate changes exactly at the GC-content transition zone from low values in the GC-poor sequences to high values in GC-rich ones. The GC content of the GC-poor sequences can be explained by a bias in favor of GC > AT mutations, whereas the GC content of the GC-rich segment may result from a fixation bias in favor of AT > GC substitutions. This fixation bias may be explained by direct selection by the GC content or by biased gene conversion. The mammalian genome is not a random sequence but shows a specific, evolutionarily conserved structure that becomes manifest in its isochore pattern. Isochores, i.e. stretches of DNA with a distinct sequence composition and thus a specific GC content, cause the chromosomal banding pattern. This fundamental level of genome organization is related to several functional features like the replication timing of a DNA sequence. GC richness of genomic regions generally corresponds to an early replication time during S phase. Recently, we demonstrated this interdependency on a molecular level for an abrupt transition from a GC-poor isochore to a GC-rich one in the NF1 gene region; this isochore boundary also separates late from early replicating chromatin. Now, we analyzed another genomic region containing four isochores separated by three sharp isochore transitions. Again, the GC-rich isochores were found to be replicating early, the GC-poor isochores late in S phase; one of the replication time zones was discovered to consist of one single replicon. At the boundaries between isochores, that all show no special sequence elements, the replication machinery stopped for several hours. Thus, our results emphasize the importance of isochores as functional genomic units, and of isochore transitions as genomic landmarks with a key function for chromosome organization and basic biological properties. The isochore structure of a genome is observable by variation in the G+C (guanine and cytosine) content within and between the chromosomes. Describing the isochore structure of vertebrate genomes is a challenging task, and many computational methods have been developed and applied to it. Here we apply a well-known least-squares optimal segmentation algorithm to isochore discovery. The algorithm finds the best division of the sequence into k pieces, such that the segments are internally as homogeneous as possible. We show how this simple segmentation method can be applied to isochore discovery using as input the G+C content of sliding windows on the sequence. To evaluate the performance of this segmentation technique on isochore detection, we present results from segmenting previously studied isochore regions of the human genome. Detailed results on the MHC locus, on parts of chromosomes 21 and 22, and on a 100 Mb region from chromosome 1 are similar to previously suggested isochore structures. We also give results on segmenting all 22 autosomal human chromosomes. An advantage of this technique is that oversegmentation of G+C rich regions can generally be avoided. This is because the technique concentrates on greater global, instead of smaller local, differences in the sequence composition. The effect is further emphasized by a log-transformation of the data that lowers the high variance that is observed in G+C rich regions. We conclude that the least-squares optimal segmentation method is computationally efficient and yields results close to previous biologically motivated isochore structures. The human genome is composed of large sequence segments with fairly homogeneous GC content, namely isochores, which have been linked to many important functions; biological implications of most isochore boundaries, however, remain elusive, partly due to the difficulty in determining these boundaries at high resolution. Using the segmentation algorithm based on the quadratic divergence, we re-determined all 79 boundaries of previously identified human isochores at single-nucleotide resolution, and then compared the boundary coordinates with other genome features. We found that 55.7% of isochore boundaries coincide with termini of repeat elements; 45.6% of isochore boundaries coincide with termini of highly conserved sequences based on alignment of 17 vertebrate genomes, i.e., the highly conserved genome sequence switches to a less or non-conserved one at the isochore boundary; some isochore boundaries coincide with abrupt change of CpG island distribution (note that one boundary can associate with more than one genome feature). In addition, sequences around isochore boundaries are highly conserved. It seems reasonable to deduce that the boundaries of all the isochores studied here would be replication timing sites in the human genome. These results suggest possible key roles of the isochore boundaries and may further our understanding of the human genome organization. The isochore theory depicts the genomes of warm-blooded vertebrates as a mosaic of long genomic regions that are characterized by relatively homogeneous GC content. In the absence of genomic data, the GC content at third-codon positions of protein-coding genes (GC3) was commonly used as a proxy for the GC content of isochores. Oddly, in the postgenomic era, GC3 is still sometimes used as a proxy for the GC composition of isochores. Here, we use genic and genomic sequences from human, chimpanzee, cow, mouse, rat, chicken, and zebrafish to show that GC3 only explains a very small proportion of the variation in GC content of long genomic sequences flanking the genes (GCf), and what little correlation there is between GC3 and GCf was found to decay rapidly with distance from the gene. The coefficient of variation of GC3 was found to be much larger than that of GCf and, therefore, GC3 and GCf values are not comparable with each other. Comparisons of orthologous gene pairs from 1) human and chimpanzee and 2) mouse and rat show strong correlations between their GC3 values, but very weak correlations between their GCf values. We conclude that the GC content of third-codon position cannot be used as stand-in for isochoric composition. Vertebrate genomes are comprised of isochores that are relatively long (>100 kb) regions with a relatively homogenous (either GC-rich or AT-rich) base composition and with rather sharp boundaries with neighboring isochores. Mammals and living archosaurs (birds and crocodilians) have heterogeneous genomes that include very GC-rich isochores. In sharp contrast, the genomes of amphibians and fishes are more homogeneous and they have a lower overall GC content. Because DNA with higher GC content is more thermostable, the elevated GC content of mammalian and archosaurian DNA has been hypothesized to be an adaptation to higher body temperatures. This hypothesis can be tested by examining structure of isochores across the reptilian clade, which includes the archosaurs, testudines (turtles), and lepidosaurs (lizards and snakes), because reptiles exhibit diverse body sizes, metabolic rates, and patterns of thermoregulation. This study focuses on a comparative analysis of a new set of expressed genes of the red-eared slider turtle and orthologs of the turtle genes in mammalian (human, mouse, dog, and opossum), archosaurian (chicken and alligator), and amphibian (western clawed frog) genomes. EST (expressed sequence tag) data from a turtle cDNA library enriched for genes that have specialized functions (developmental genes) revealed using the GC content of the third-codon-position to examine isochore structure requires careful consideration of the types of genes examined. The more highly expressed genes (e.g., housekeeping genes) are more likely to be GC-rich than are genes with specialized functions. However, the set of highly expressed turtle genes demonstrated that the turtle genome has a GC content that is intermediate between the GC-poor amphibians and the GC-rich mammals and archosaurs. There was a strong correlation between the GC content of all turtle genes and the GC content of other vertebrate genes, with the slope of the line describing this relationship also indicating that the isochore structure of turtles is intermediate between that of amphibians and other amniotes. These data are consistent with some thermal hypotheses of isochore evolution, but we believe that the credible set of models for isochore evolution still includes a variety of models. These data expand the amount of genomic data available from reptiles upon which future studies of reptilian genomics can build. Isochores are large regions of relatively homogeneous nucleotide composition and are present in the genomes of all mammals and birds that have been sequenced to date. The newly sequenced genome of Anolis carolinensis provides the first opportunity to quantify isochore structure in a nonavian reptile. We find Anolis to have the most compositionally homogeneous genome of all amniotes sequenced thus far, a homogeneity exceeding that for the frog Xenopus. Based on a Bayesian algorithm, Anolis has smaller and less GC-rich isochores compared with human and chicken. Correlates generally associated with GC-rich isochores, including shorter introns and higher gene density, have all but disappeared from the Anolis genome. Using genic GC as a proxy for isochore structure so as to compare with other vertebrates, we found that GC content has substantially decreased in the lineage leading to Anolis since diverging from the common ancestor of Reptilia ∼275 Ma, perhaps reflecting weakened or reversed GC-biased gene conversion, a nonadaptive substitution process that is thought to be important in the maintece and trajectory of isochore evolution. Our results demonstrate that GC composition in Anolis is not associated with important features of genome structure, including gene density and intron size, in contrast to patterns seen in mammal and bird genomes.

Is tubulin acetylation involved in cell motility?

Yes, induction of alpha-tubulin acetylation correlates with inhibition of cell motility, while it is involved in additional cellular processes, e.g. cell cycle progression, differentiation, intracellular trafficking, and signalling. Dynamic microtubule (MT) acetylation/deacetylation mediating cell motility and adhesion is controlled by enzymes such as HDAC6, a major cytoplasmic α-tubulin deacetylase. While its overexpression and activation is capable to enhance cell motility, HDAC6 activity can also be negatively regulated by a number of cellular inhibitors, thus decreasing the ability of cells for migration.

Cell motility and adhesion involves dynamic microtubule (MT) acetylation/deacetylation, a process regulated by enzymes as HDAC6, a major cytoplasmic α-tubulin deacetylase. We identify G protein-coupled receptor kinase 2 (GRK2) as a key novel stimulator of HDAC6. GRK2, which levels inversely correlate with the extent of α-tubulin acetylation in epithelial cells and fibroblasts, directly associates with and phosphorylates HDAC6 to stimulate α-tubulin deacetylase activity. Remarkably, phosphorylation of GRK2 itself at S670 specifically potentiates its ability to regulate HDAC6. GRK2 and HDAC6 colocalize in the lamellipodia of migrating cells, leading to local tubulin deacetylation and enhanced motility. Consistently, cells expressing GRK2-K220R or GRK2-S670A mutants, unable to phosphorylate HDAC6, exhibit highly acetylated cortical MTs and display impaired migration and protrusive activity. Finally, we find that a balanced, GRK2/HDAC6-mediated regulation of tubulin acetylation differentially modulates the early and late stages of cellular spreading. This novel GRK2/HDAC6 functional interaction may have important implications in pathological contexts. G protein-coupled receptor kinase 2 (GRK2) is a ubiquitous, essential protein kinase that is emerging as an integrative node in many signaling networks. Moreover, changes in GRK2 abundance and activity have been identified in several inflammatory, cardiovascular disease, and tumor contexts, suggesting that those alterations may contribute to the initiation or development of pathologies. GRKs were initially identified as key players in the desensitization and internalization of multiple G protein-coupled receptors (GPCRs), but GRK2 also phosphorylates several non-GPCR substrates and dynamically associates with a variety of proteins related to signal transduction. Ongoing research in our laboratory is aimed at understanding how specific GRK2 interactomes are orchestrated in a stimulus-, context-, or cell type-specific manner. We have recently identified an interaction between GRK2 and histone deacetylase 6 (HDAC6) that modulates cell spreading and motility. HDAC6 is a major cytoplasmic a-tubulin deacetylase that is involved in cell motility and adhesion. GRK2 dynamically and directly associates with and phosphorylates HDAC6 to stimulate its a-tubulin deacetylase activity at specific cellular localizations, such as the leading edge of migrating cells, thus promoting local tubulin deacetylation and enhanced motility. GRK2-HDAC6-mediated regulation of tubulin acetylation also modulates cellular spreading. This GRK2-HDAC6 functional interaction may have important implications in pathological contexts related to epithelial cell migration. Taxanes are potent inhibitors of cell motility, a property implicated in their antiangiogenic and antimetastatic activity and unrelated to their antiproliferative effect. The molecular mechanism of this anti-motility activity is poorly understood. In this study, we found that paclitaxel induced tubulin acetylation in endothelial and tumor cells, at concentrations that affected cell motility but not proliferation (10(-8) to 10(-9) M, for 4 hours). Induction of tubulin acetylation correlated with inhibition of motility but not proliferation based on a comparison of highly and poorly cytotoxic taxanes (paclitaxel and IDN5390) and tumor cell lines sensitive and resistant to paclitaxel (1A9 and 1A9 PTX22). Consistent with the hypothesis that tubulin deacetylase activity might affect cell response to the anti-motility activity of taxanes, we found that overexpression of the tubulin deacetylase SIRT2 increased cell motility and reduced cell response to the anti-motility activity of paclitaxel. Conversely, the SIRT2 inhibitor splitomicin reduced cell motility and potentiated the anti-motility activity of paclitaxel. The inhibitory effect was further potentiated by the addition of the HDAC6 inhibitor trichostatin A. Paclitaxel and splitomicin promoted translocation into the nucleus--and hence activation--of FOXO3a, a negative regulator of cell motility. This study indicates a role for SIRT2 in the regulation of cell motility and suggests that therapies combining sirtuin inhibitors and taxanes could be used to treat cell motility-based pathologic processes such as tumor angiogenesis, invasion, and metastasis.

List available genetic multicolor cell labeling techiniques in Drosophila

Flybow and Drosophila Brainbow.

To facilitate studies of neural network architecture and formation, we generated three Drosophila melanogaster variants of the mouse Brainbow-2 system, called Flybow. Sequences encoding different membrane-tethered fluorescent proteins were arranged in pairs within cassettes flanked by recombination sites. Flybow combines the Gal4-upstream activating sequence binary system to regulate transgene expression and an inducible modified Flp-FRT system to drive inversions and excisions of cassettes. This provides spatial and temporal control over the stochastic expression of one of two or four reporters within one sample. Using the visual system, the embryonic nervous system and the wing imaginal disc, we show that Flybow in conjunction with specific Gal4 drivers can be used to visualize cell morphology with high resolution. Finally, we demonstrate that this labeling approach is compatible with available Flp-FRT-based techniques, such as mosaic analysis with a repressible cell marker; this could further support the genetic analysis of neural circuit assembly and function. We developed a multicolor neuron labeling technique in Drosophila melanogaster that combines the power to specifically target different neural populations with the label diversity provided by stochastic color choice. This adaptation of vertebrate Brainbow uses recombination to select one of three epitope-tagged proteins detectable by immunofluorescence. Two copies of this construct yield six bright, separable colors. We used Drosophila Brainbow to study the innervation patterns of multiple antennal lobe projection neuron lineages in the same preparation and to observe the relative trajectories of individual aminergic neurons. Nerve bundles, and even individual neurites hundreds of micrometers long, can be followed with definitive color labeling. We traced motor neurons in the subesophageal ganglion and correlated them to neuromuscular junctions to identify their specific proboscis muscle targets. The ability to independently visualize multiple lineage or neuron projections in the same preparation greatly advances the goal of mapping how neurons connect into circuits.

Which growth factors are known to be involved in the induction of EMT?

EMT is characterized by acquisition of cell motility, modifications of cell morphology, and cell dissociation correlating with the loss of desmosomes from the cellular cortex. A number of growth factors have been shown to be involved in this process. These include fibroblast growth factors (FGFs), TGF-β1, TGF-β2, TNF-α, CCN family, Sonic Hedgehog (SHh), Notch1, GF-β, Wnt, EGF, bFGF, IGF-I and IGF-II.

Transforming growth factors beta (TGF-betas) inhibit growth of epithelial cells and induce differentiation changes, such as epithelial-mesenchymal transition (EMT). On the other hand, bone morphogenetic proteins (BMPs) weakly affect epithelial cell growth and do not induce EMT. Smad4 transmits signals from both TGF-beta and BMP pathways. Stimulation of Smad4-deficient epithelial cells with TGF-beta 1 or BMP-7 in the absence or presence of exogenous Smad4, followed by cDNA microarray analysis, revealed 173 mostly Smad4-dependent, TGF-beta-, or BMP-responsive genes. Among 25 genes coregulated by both factors, inhibitors of differentiation Id2 and Id3 showed long-term repression by TGF-beta and sustained induction by BMP. The opposing regulation of Id genes is critical for proliferative and differentiation responses. Hence, ectopic Id2 or Id3 expression renders epithelial cells refractory to growth inhibition and EMT induced by TGF-beta, phenocopying the BMP response. Knockdown of endogenous Id2 or Id3 sensitizes epithelial cells to BMP, leading to robust growth inhibition and induction of transdifferentiation. Thus, Id genes sense Smad signals and create a permissive or refractory nuclear environment that defines decisions of cell fate and proliferation. Epithelial-to-mesenchymal transition (EMT) has emerged as a critical event in the pathogenesis of tubulointerstitial fibrosis. EMT is typically induced by transforming growth factor-beta1 (TGF-beta1) and inhibited by hepatocyte growth factor (HGF). The present study was undertaken to evaluate the potential role of cyclooxygenase (COX)-2-derived PGE2 in regulation of EMT in cultured Madin-Darby canine kidney (MDCK) cells, in the setting of HGF treatment. Exposure to 50 ng/ml HGF significantly induced COX-2 protein expression and PGE2 release, whereas other growth factors, including epidermal growth factor, the insulin-like growth factor I protein, platelet-derived growth factor-BB, and TGF-beta1, had no effects on COX-2 expression or PGE2 release. COX-2 induction by HGF was preceded by activation of ERK1/2, and an ERK1/2-specific inhibitor, U-0126 (10 microM), completely abolished HGF-induced COX-2 expression. Exposure of MDCK cells to 10 ng/ml TGF-beta1 for 72 h induced EMT as evidenced by conversion to the spindle-like morphology, loss of E-cadherin, and activation of alpha-smooth muscle actin. In contrast, treatment with 1 microM PGE2 completely blocked EMT, associated with a significant elevation of intracellular cAMP and complete blockade of TGF-beta1-induced oxidant production. cAMP-elevating agents, including 8-Br-cAMP, forskolin, and IBMX, inhibited EMT and associated oxidative stress induced by TGF-beta1, but inhibition of cAMP pathway with Rp-cAMP, the cAMP analog, and H89, the protein kinase A (PKA) inhibitor, did not block the effect of PGE2. The effect of HGF on EMT was inhibited by approximately 50% in the presence of a COX-2 inhibitor SC-58635 (10 microM). Therefore, our data suggest that PGE2 inhibits EMT via inhibition of oxidant production and COX-2-derived PGE2 partially accounts for the antifibrotic effect of HGF. Transforming growth factor-alpha (TGF-alpha) stimulates while TGF-beta inhibits mammary epithelial cell growth, suggesting that when cells are treated concurrently with the growth factors their combined effects would result in no net growth. However, combined treatments stimulate proliferation and cellular transformation in several cell lines. The objective of this paper was to describe the effect of long-term (6 days) concurrent TGF-alpha and TGF-beta treatment on normal mammary epithelial cell growth pattern, morphology, and gene expression. Growth curve analysis showed that TGF-alpha enhanced while TGF-beta suppressed growth rate until Day 4, when cells entered lag phase. However, cells treated concurrently with both growth factors exhibited a dichotomous pattern of growth marked by growth and death phases (with no intermittent lag phase). These changes in growth patterns were due to a marked induction of cell death from Day 2 (16.5%) to Day 4 (89.5%), resulting in the transition from growth to death phases, even though the combined treated cultures had significantly more (P < 0.05) cells in S phase on Day 4. TGF-beta stimulated epithelial to mesenchyme transdifferentiation (EMT) in the presence of TGF-alpha, as characterized by increased expression of fibronectin and changes in TGF-beta receptor binding. Expression patterns of genes that regulate the cell cycle showed significant interaction between treatment and days, with TGF-beta overriding TGF-alpha-stimulated effects on gene expression. Overall, the combined treatments were marked by enhanced rates of cellular proliferation, death, and trans-differentiation, behaviors reminiscent of breast tumors, and thus this system may serve as a good model to study breast tumorigenesis. Epithelial-mesenchymal transition (EMT) is believed to play an important role in fibrosis and tumor invasion. EMT can be induced in vitro cell culture by various stimuli including growth factors and matrix metalloproteinases. In this study, we report that cytomix (a mixture of IL-1beta, TNF-alpha and IFN-gamma) significantly enhances TGF-beta1-induced EMT in A549 cells as evidenced by acquisition of fibroblast-like cell shape, loss of E-cadherin, and reorganization of F-actin. IL-1beta or TNF-alpha alone can also augment TGF-beta1-induced EMT. However, a combination of IL-1beta and TNF-alpha or the cytomix is more potent to induce EMT. Cytomix, but not individual cytokine of IL-1beta, TNF-alpha or IFN-gamma, significantly up-regulates expression of TGF-beta receptor type I (TbetaR-I). Suppression of TbetaR-I, Smad2 or Smad3 by siRNA partially blocks EMT induction by cytomix plus TGF-beta1, indicating cytomix augments TGF-beta1-induced EMT through enhancing TbetaR-I and Smad signaling. These results indicate that inflammatory cytokines together with TGF-beta1 may play an important role in the development of fibrosis and tumor progress via the mechanism of epithelial-mesenchymal transition. As a rich source of pro-fibrogenic growth factors and matrix metalloproteinases (MMPs), macrophages are well-placed to play an important role in renal fibrosis. However, the exact underlying mechanisms and the extent of macrophage involvement are unclear. Tubular cell epithelial-mesenchymal transition (EMT) is an important contributor to renal fibrosis and MMPs to induction of tubular cell EMT. The aim of this study was to investigate the contribution of macrophages and MMPs to induction of tubular cell EMT. The murine C1.1 tubular epithelial cell line and primary tubular epithelial cells were cultured in activated macrophage-conditioned medium (AMCM) derived from lipopolysaccharide-activated J774 macrophages. MMP-9, but not MMP-2 activity was detected in AMCM. AMCM-induced tubular cell EMT in C1.1 cells was inhibited by broad-spectrum MMP inhibitor (GM6001), MMP-2/9 inhibitor, and in AMCM after MMP-9 removal by monoclonal Ab against MMP-9. AMCM-induced EMT in primary tubular epithelial cells was inhibited by MMP-2/9 inhibitor. MMP-9 induced tubular cell EMT in both C1.1 cells and primary tubular epithelial cells. Furthermore, MMP-9 induced tubular cell EMT in C1.1 cells to an extent similar to transforming growth factor-beta. Transforming growth factor-beta-induced tubular cell EMT in C1.1 cells was inhibited by MMP-2/9 inhibitor. Our in vitro study provides evidence that MMPs, specifically MMP-9, secreted by effector macrophages can induce tubular cell EMT and thereby contribute to renal fibrosis. Tumors are cellularly and molecularly heterogeneous, with subsets of undifferentiated cancer cells exhibiting stem cell-like features (CSCs). Epithelial to mesenchymal transitions (EMT) are transdifferentiation programs that are required for tissue morphogenesis during embryonic development. The EMT process can be regulated by a diverse array of cytokines and growth factors, such as transforming growth factor (TGF)-beta, whose activities are dysregulated during maligt tumor progression. Thus, EMT induction in cancer cells results in the acquisition of invasive and metastatic properties. Recent reports indicate that the emergence of CSCs occurs in part as a result of EMT, for example, through cues from tumor stromal components. Recent evidence now indicates that EMT of tumor cells not only causes increased metastasis, but also contributes to drug resistance. In this review, we will provide potential mechanistic explanations for the association between EMT induction and the emergence of CSCs. We will also highlight recent studies implicating the function of TGF-beta-regulated noncoding RNAs in driving EMT and promoting CSC self-renewal. Finally we will discuss how EMT and CSCs may contribute to drug resistance, as well as therapeutic strategies to overcome this clinically. BACKGROUND AND PURPOSE: Hypoxia is a hallmark of solid cancers and associated with metastases and treatment failure. During tumor progression epithelial cells often acquire mesenchymal features, a phenomenon known as epithelial-to-mesenchymal transition (EMT). Intratumoral hypoxia has been linked to EMT induction. We hypothesized that signals from the tumor microenvironment such as growth factors and tumor oxygenation collaborate to promote EMT and thereby contribute to radioresistance. MATERIALS AND METHODS: Gene expression changes under hypoxia were analyzed using microarray and validated by qRT-PCR. Conversion of epithelial phenotype upon hypoxic exposure, TGFβ addition or oncogene activation was investigated by Western blot and immunofluorescence. Cell survival following ionizing radiation was assayed using clonogenic survival. RESULTS: Upon hypoxia, TGFβ addition or EGFRvIII expression, MCF7, A549 and NMuMG epithelial cells acquired a spindle shape and lost cell-cell contacts. Expression of epithelial markers such as E-cadherin decreased, whereas mesenchymal markers such as vimentin and N-cadherin increased. Combining hypoxia with TGFβ or EGFRvIII expression, lead to more rapid and pronounced EMT-like phenotype. Interestingly, E-cadherin expression and the mesenchymal appearance were reversible upon reoxygenation. Mesenchymal conversion and E-cadherin loss were associated with radioresistance. CONCLUSIONS: Our findings describe a mechanism by which the tumor microenvironment may contribute to tumor radioresistance via E-cadherin loss and EMT. Sialyl Lewis x (sLe(x)) and sialyl Lewis a (sLe(a)) glycans are expressed on highly metastatic colon cancer cells. They promote extravasation of cancer cells and tumor angiogenesis via interacting with E-selectin on endothelial cells. Recently, epithelial-mesenchymal transition (EMT) has been noted as a critical phenotypic alteration in metastatic cancer cells. To address the association between sLe(x/a) expression and EMT, we assessed whether sLe(x/a) are highly expressed on colon cancer cells undergoing EMT. Treatment of HT29 and DLD-1 cells with EGF and/or basic FGF (bFGF) induced EMT and significantly increased sLe(x/a) expression resulting in enhanced E-selectin binding activity. The transcript levels of the glycosyltransferase genes ST3GAL1/3/4 and FUT3 were significantly elevated and that of FUT2 was significantly suppressed by the treatment. We provide evidence that ST3GAL1/3/4 and FUT3 are transcriptionally up-regulated by c-Myc with probable involvement of Ser62 phosphorylation, and that FUT2 is transcriptionally down-regulated through the attenuation of CDX2. The contribution of c-Myc and CDX2 to the sLe(x/a) induction was proved to be significant by knockdown or forced expression experiments. Interestingly, the cells undergoing EMT exhibited significantly increased VEGF secretion, which can promote tumor angiogenesis in cooperation with sLe(x/a). Finally, immunohistological study indicated high E-selectin ligand expression on cancer cells undergoing EMT in vivo, supporting their coexistence observed in vitro. These results suggest a significant link between sLe(x/a) expression and EMT in colon cancer cells and a pivotal role of c-Myc and CDX2 in regulating sLe(x/a) expression during EMT. Metastatic spread of tumor cells to vital organs is the major cause of death in cancer. Accumulating data support an important role of infiltrating immune cells in promoting carcinoma progression into metastatic disease. Tumor-infiltrating immune cells produce and secrete cytokines, growth factors and proteases that re-activate latent developmental processes including epithelial-mesenchymal transition (EMT). EMT provides tumor cells with invasive, migratory and stem cell properties allowing them to disseminate and propagate at distant sites. Induction of EMT requires two criteria to be fulfilled: (i) cells are competent to undergo EMT (ii) an EMT-permissive microenvironment exists. The cytokine TGF-β, which is expressed by tumor-infiltrating immune cells, stands out as a master regulator of the pro-invasive tumor microenvironment. TGF-β cooperates with stem cell pathways, such as Wnt and Ras signaling, to induce EMT. In addition, TGF-β contributes to an EMT-permissive microenvironment by switching the phenotypes of tumor-infiltrating immune cells, which thereby mount pro-invasive and pro-metastatic immune responses. In this review, we discuss the role of TGF-β-induced EMT as a link between cancer and inflammation in the context of questions, which from our point of view are key to answer in order to understand the functionality of EMT in tumors. CCN1 is a matricellular protein and a member of the CCN family of growth factors. CCN1 is associated with the development of various cancers including pancreatic ductal adenocarcinoma (PDAC). Our recent studies found that CCN1 plays a critical role in pancreatic carcinogenesis through the induction of EMT and stemness. CCN1 mRNA and protein were detected in the early precursor lesions, and their expression intensified with disease progression. However, biochemical activity and the molecular targets of CCN1 in pancreatic cancer cells are unknown. Here we show that CCN1 regulates the Sonic Hedgehog (SHh) signaling pathway, which is associated with the PDAC progression and poor prognosis. SHh regulation by CCN1 in pancreatic cancer cells is mediated through the active Notch-1. Notably, active Notch-1is recruited by CCN1 in these cells via the inhibition of proteasomal degradation results in stabilization of the receptor. We find that CCN1-induced activation of SHh signaling might be necessary for CCN1-dependent in vitro pancreatic cancer cell migration and tumorigenicity of the side population of pancreatic cancer cells (cancer stem cells) in a xenograft in nude mice. Moreover, the functional role of CCN1 could be mediated through the interaction with the αvβ3 integrin receptor. These extensive studies propose that targeting CCN1 can provide a new treatment option for patients with pancreatic cancer since blocking CCN1 simultaneously blocks two critical pathways (i.e. SHh and Notch1) associated with the development of the disease as well as drug resistance. Proliferative vitreo retinopathy (PVR) is associated with extracellular matrix membrane (ECM) formation on the neural retina and disruption of the multilayered retinal architecture leading to distorted vision and blindness. During disease progression in PVR, retinal pigmented epithelial cells (RPE) lose cell-cell adhesion, undergo epithelial-to-mesenchymal transition (EMT), and deposit ECM leading to tissue fibrosis. The EMT process is mediated via exposure to vitreous cytokines and growth factors such as TGF-β2. Previous studies have shown that Na,K-ATPase is required for maintaining a normal polarized epithelial phenotype and that decreased Na,K-ATPase function and subunit levels are associated with TGF-β1-mediated EMT in kidney cells. In contrast to the basolateral localization of Na,K-ATPase in most epithelia, including kidney, Na,K-ATPase is found on the apical membrane in RPE cells. We now show that EMT is also associated with altered Na,K-ATPase expression in RPE cells. TGF-β2 treatment of ARPE-19 cells resulted in a time-dependent decrease in Na,K-ATPase β1 mRNA and protein levels while Na,K-ATPase α1 levels, Na,K-ATPase activity, and intracellular sodium levels remained largely unchanged. In TGF-β2-treated cells reduced Na,K-ATPase β1 mRNA inversely correlated with HIF-1α levels and analysis of the Na,K-ATPase β1 promoter revealed a putative hypoxia response element (HRE). HIF-1α bound to the Na,K-ATPase β1 promoter and inhibiting the activity of HIF-1α blocked the TGF-β2 mediated Na,K-ATPase β1 decrease suggesting that HIF-1α plays a potential role in Na,K-ATPase β1 regulation during EMT in RPE cells. Furthermore, knockdown of Na,K-ATPase β1 in ARPE-19 cells was associated with a change in cell morphology from epithelial to mesenchymal and induction of EMT markers such as α-smooth muscle actin and fibronectin, suggesting that loss of Na,K-ATPase β1 is a potential contributor to TGF-β2-mediated EMT in RPE cells. BACKGROUND: Epithelial-mesenchymal transition (EMT) is a crucial process in cancer progression that provides cancer cells with the ability to escape from the primary focus, invade stromal tissues and migrate to distant regions. Cell lines that lack E-cadherin show increased tumorigenesis and metastasis, and the expression levels of E-cadherin and Snail correlate inversely with the prognosis of patients suffering from breast cancer or oral squamous cell carcinoma (OSCC). Moreover, recent studies have shown that most EMT cases are regulated by soluble growth factors or cytokines. Among these factors, fibroblast growth factors (FGFs) execute diverse functions by binding to and activating members of the FGF receptor (FGFR) family, including FGFR1-4. Fibroblast growth factor receptor 1 is an oncoprotein that is involved in tumorigenesis, and PD173074 is known to be a selective inhibitor of FGFR1. However, the roles of FGFR1 and FGFR1 inhibitors have not yet been examined in detail. METHODS: Here, we investigated the expression of FGFR1 in head and neck squamous cell carcinoma (HNSCC) and the role of the FGFR1 inhibitor PD173074 in carcinogenesis and the EMT process. RESULTS: Fibroblast growth factor receptor 1 was highly expressed in 54% of HNSCC cases and was significantly correlated with maligt behaviours. Nuclear FGFR1 expression was also observed and correlated well with histological differentiation, the pattern of invasion and abundant nuclear polymorphism. Fibroblast growth factor receptor 1 was also overexpressed in EMT cell lines compared with non-EMT cell lines. Furthermore, treatment of HOC313 cells with PD173074 suppressed cellular proliferation and invasion and reduced ERK1/2 and p38 activation. These cells also demonstrated morphological changes, transforming from spindle- to cobble stone-like in shape. In addition, the expression levels of certain matrix metalloproteinases (MMPs), whose genes contain activator protein-1 (AP-1) promoter sites, as well as Snail1 and Snail2 were reduced following PD173074 treatment. CONCLUSION: Taken together, these data suggest that PD173074 inhibits the MAPK pathway, which regulates the activity of AP-1 and induces MET. Furthermore, this induction of MET likely suppresses cancer cell growth and invasion.

What is the function of the yeast protein Aft1?

The Aft1 transcription factor regulates the iron regulon in response to iron availability in Saccharomyces cerevisiae. Aft1 activates a battery of genes required for iron uptake under iron-starved conditions, whereas Aft1 function is inactivated under iron-replete conditions. Aft1 interacts with the FOB (ferrioxamine B) transporter Arn3 and may regulate the ubiquitination of Arn3 in the cytosolic compartment. Aft1 has been implicated in numerous cellular processes including cell-cycle progression and chromosome stability. Aft1 has also been shown to affect a diverse range of cellular processes, including the RIM101 pH pathway, cell-wall stability, DNA damage, protein transport, chromosome stability, mitochondrial function, while it was recently shown to interact with the kinetochore protein Iml3 and to promote pericentromeric cohesin.

Iron deprivation of Saccharomyces cerevisiae induces transcription of genes required for high-affinity iron uptake. AFT1 mediates this transcriptional control. In this report, the 5'-flanking region of FET3, which encodes a copper-dependent oxidase required for iron transport, was analyzed and found to contain a DNA sequence responsible for AFT1-regulated gene expression. AFT1 was capable of interacting specifically with this DNA sequence. A core element within this DNA sequence necessary for the binding of AFT1 was also determined. In vivo footprinting demonstrated occupancy of the AFT1 binding site in cells deprived of iron and not in cells grown in the presence of iron. Thus, the environmental signal resulting from iron deprivation was transduced through the regulated binding of AFT1 to the FET3 promoter, followed by the activation of transcription. A regulon of genes under the control of AFT1 could be defined. AFT1 was able to bind to a consensus binding site (PyPuCACCCPu) in the 5' region of FRE1, FRE2, FTR1, FTH1 and CCC2. High-affinity iron uptake in Saccharomyces cerevisiae involves the extracytoplasmic reduction of ferric ions by FRE1 and FRE2 reductases. Ferrous ions are then transported across the plasma membrane through the FET3 oxidase-FTR1 permease complex. Expression of the high-affinity iron uptake genes is induced upon iron deprivation. We demonstrate that AFT1 is differentially involved in such regulation. Aft1 protein is required for maintaining detectable non-induced level of FET3 expression and for induction of FRE2 in iron starvation conditions. On the contrary, FRE1 mRNA induction is normal in the absence of Aft1, although the existence of AFT1 point mutations causing constitutive expression of FRE1 (Yamaguchi-Iwai et al., EMBO J. 14: 1231-1239, 1995) indicates that Aft1 may also participate in FRE1 expression in a dispensable way. The alterations in the basal levels of expression of the high-affinity iron uptake genes may explain why the AFT1 mutant is unable to grow on respirable carbon sources. Overexpression of AFT1 leads to growth arrest of the G1 stage of the cell cycle. Aft1 is a transcriptional activator that would be part of the different transcriptional complexes interacting with the promoter of the high-affinity iron uptake genes. Aft1 displays phosphorylation modifications depending on the growth stage of the cells, and it might link induction of genes for iron uptake to other metabolically domit requirement for cell growth. A pathogen such as C. albicans needs an efficient mechanism of iron uptake in an iron-restricted environment such as is the human body. A ferric-reductase activity regulated by iron and copper, and analogous to that in S. cerevisiae, has been described in C. albicans. We have developed an in-plate protocol for the isolation of clones that complement an aft1 mutation in S. cerevisiae that makes cells dependent on iron for growth. After transformation of S. cerevisiae aft1 with a C. albicans library, we have selected clones that grow in conditions of iron deficiency and share an identical plasmid, pIRO1, with a 4500 bp insert containing the URA3 gene and an ORF (IRO1) responsible for the suppression of the iron dependency. IRO1 does not show homology with AFT1 or with other sequences in the databases. Northern analysis demonstrates constitutive expression of IRO1. CAI4, a C. albicans strain isolated as Deltaura3, also has a deletion of the 3' half of IRO1, and displays in YNB medium similar phenotypic characteristics to S. cerevisiae aft1 mutant strains. Therefore, we consider IRO1 as a gene of C. albicans involved in the utilization of iron. However, in extreme conditions of iron deprivation, CAI4 seems to activate alternative mechanisms of iron uptake that allow a better growth than the wild strain SC5314. Analysis of its predicted protein sequence is in agreement with a role of Iro1p as a transcription factor. The Aft1 transcription factor regulates the iron regulon in response to iron availability in Saccharomyces cerevisiae. Aft1 activates a battery of genes required for iron uptake under iron-starved conditions, whereas Aft1 function is inactivated under iron-replete conditions. Previously, we have shown that iron-regulated DNA binding by Aft1 is responsible for the controlled expression of target genes. Here we show that this iron-regulated DNA binding by Aft1 is not due to the change in the total expression level of Aft1 or alteration of DNA binding activity. Rather, nuclear localization of Aft1 responds to iron status, leading to iron-regulated expression of the target genes. We identified the nuclear export signal (NES)-like sequence in the AFT1 open reading frame. Mutation of the NES-like sequence causes nuclear retention of Aft1 and the constitutive activation of Aft1 function independent of the iron status of the cells. These results suggest that the nuclear export of Aft1 is critical for ensuring iron-responsive transcriptional activation of the Aft1 regulon and that the nuclear import/export systems are involved in iron sensing by Aft1 in S. cerevisiae. We found Nhp6a/b yeast HMG-box chromatin-associated architectural factors and Ssn6 (Cyc8) corepressor to be crucial transcriptional coactivators of FRE2 gene. FRE2 encoding a plasma membrane ferric reductase is induced by the iron-responsive, DNA-binding, transcriptional activator Aft1. We have shown that Nhp6 interacts directly with the Aft1 N-half, including the DNA-binding region, to facilitate Aft1 binding at FRE2 UAS. Ssn6 also interacts directly with the Aft1 N-half and is recruited on FRE2 promoter only in the presence of both Aft1 and Nhp6. This Nhp6/Ssn6 role in Aft1-mediated transcription is FRE2 promoter context specific, and both regulators are required for activation-dependent chromatin remodeling. Our results provide the first in vivo biochemical evidence for nonsequence-specific HMG-box protein-facilitated recruitment of a yeast gene-specific transactivator to its DNA target site and for Nhp6-mediated Ssn6 promoter recruitment. Ssn6 has an explicitly coactivating role on FRE2 promoter only upon induction. Therefore, transcriptional activation in response to iron availability involves multiple protein interactions between the Aft1 iron-responsive DNA-binding factor and global regulators such as Nhp6 and Ssn6. Two transcriptional activators, Aft1 and Aft2, regulate iron homeostasis in Saccharomyces cerevisiae. These factors induce the expression of iron regulon genes in iron-deficient yeast but are inactivated in iron-replete cells. Iron inhibition of Aft1/Aft2 is abrogated in cells defective for Fe-S cluster biogenesis within the mitochondrial matrix (Chen, O. S., Crisp, R. J., Valachovic, M., Bard, M., Winge, D. R., and Kaplan, J. (2004) J. Biol. Chem. 279, 29513-29518). To determine whether iron sensing by Aft1/Aft2 requires the function of the mitochondrial Fe-S export and cytosolic Fe-S protein assembly systems, we evaluated the expression of the iron regulon in cells depleted of glutathione and in cells depleted of Atm1, Nar1, Cfd1, and Nbp35. The iron regulon is induced in cells depleted of Atm1 with Aft1 largely responsible for the induced gene expression. Aft2 is activated at a later time in Atm1-depleted cells. Likewise, the iron regulon is induced in cells depleted of glutathione. In contrast, repression of NAR1, CFD1, or NBP35 fails to induce the iron regulon despite strong inhibition of cytosolic/nuclear Fe-S protein assembly. Thus, iron sensing by Aft1/Aft2 is not linked to the maturation of cytosolic/nuclear Fe-S proteins, but the mitochondrial inner membrane transporter Atm1 is important to transport the inhibitory signal. Although Aft1 and Aft2 sense a signal emanating from the Fe-S cluster biogenesis pathway, there is no indication that the proteins are inhibited by direct binding of an Fe-S cluster. The yeast Saccharomyces cerevisiae contains a pair of paralogous iron-responsive transcription activators, Aft1 and Aft2. Aft1 activates the cell surface iron uptake systems in iron depletion, while the role of Aft2 remains poorly understood. This study compares the functions of Aft1 and Aft2 in regulating the transcription of genes involved in iron homeostasis, with reference to the presence/absence of the paralog. Cluster analysis of DNA microarray data identified the classes of genes regulated by Aft1 or Aft2, or both. Aft2 activates the transcription of genes involved in intracellular iron use in the absence of Aft1. Northern blot analyses, combined with chromatin immunoprecipitation experiments on selected genes from each class, demonstrated that Aft2 directly activates the genes SMF3 and MRS4 involved in mitochondrial and vacuolar iron homeostasis, while Aft1 does not. Computer analysis found different cis-regulatory elements for Aft1 and Aft2, and transcription analysis using variants of the FET3 promoter indicated that Aft1 is more specific for the canonical iron-responsive element TGCACCC than is Aft2. Finally, the absence of either Aft1 or Aft2 showed an iron-dependent increase in the amount of the remaining paralog. This may provide additional control of cellular iron homeostasis. The transcription factors Aft1 and Aft2 from Saccharomyces cerevisiae regulate the expression of genes involved in iron homeostasis. These factors induce the expression of iron regulon genes in iron-deficient yeast but are inactivated in iron-replete cells. Iron inhibition of Aft1/Aft2 was previously shown to be dependent on mitochondrial components required for cytosolic iron sulfur protein biogenesis. We presently show that the nuclear monothiol glutaredoxins Grx3 and Grx4 are critical for iron inhibition of Aft1 in yeast cells. Cells lacking both glutaredoxins show constitutive expression of iron regulon genes. Overexpression of Grx4 attenuates wild type Aft1 activity. The thioredoxin-like domain in Grx3 and Grx4 is dispensable in mediating iron inhibition of Aft1 activity, whereas the conserved cysteine that is part of the conserved CGFS motif in monothiol glutaredoxins is essential for this function. Grx3 and Grx4 interact with Aft1 as shown by two-hybrid interactions and co-immunoprecipitation assays. The interaction between glutaredoxins and Aft1 is not modulated by the iron status of cells but is dependent on the conserved glutaredoxin domain Cys residue. Thus, Grx3 and Grx4 are novel components required for Aft1 iron regulation that most likely occurs in the nucleus. The response of Saccharomyces cerevisiae to cisplatin was investigated by examining variations in gene expression using cDNA microarrays and confirming the results by reverse transcription polymerase chain reaction (RT-PCR). The mRNA levels of 14 proteins involved in iron homeostasis were shown to be increased by cisplatin. Interestingly, the expression of all 14 genes is known to be regulated by Aft1, a transcription factor activated in response to iron insufficiency. The promoter of one of these genes, FET3, has been relatively well studied, so we performed a reporter assay using the FET3 promoter and showed that an Aft1 binding site in the promoter region is indispensable for induction of transcription by cisplatin. The active domain of Aft1 necessary for activation of the FET3 promoter by cisplatin is identical to the one required for activation by bathophethroline sulfonate, an inhibitor of cellular iron uptake. Furthermore, we found that cisplatin inhibits the uptake of (55)Fe(II) into yeast cells. These findings suggest that cisplatin activates Aft1 through the inhibition of iron uptake into the cells, after which the expression of Aft1 target genes involved in iron uptake might be induced. Aft1 is a transcriptional activator in Saccharomyces cerevisiae that responds to iron availability and regulates the expression of genes in the iron regulon, such as FET3, FTR1 and the ARN family. Using a two-hybrid screen, we found that Aft1 physically interacts with the FOB (ferrioxamine B) transporter Arn3. This interaction modulates the ability of Arn3 to take up FOB. The interaction between Arn3 and Aft1 was confirmed by beta-galactosidase, co-immunoprecipitation and SPR (surface plasmon resoce) assays. Truncated Aft1 had a stronger interaction with Arn3 and caused a higher FOB-uptake activity than full-length Aft1. Interestingly, only full-length Aft1 induced the correct localization of Arn3 in response to FOB. Furthermore, we found Aft1 affected Arn3 ubiquitination. These results suggest that Aft1 interacts with Arn3 and may regulate the ubiquitination of Arn3 in the cytosolic compartment. Saccharomyces cerevisiae can import iron through a high-affinity system consisting of the Ftr1/Fet3-mediated reductive pathway and the siderophore-mediated non-reductive one. Expression of components of the high-affinity system is controlled by the Aft1 transcriptional factor. In this study we show that, upon oxidative stress, Aft1 is transitorily internalized into the nucleus, followed by transcription activation of components of its regulon. In these conditions, the mRNA levels of the genes of the non-reductive pathway become increased, while those of FTR1 and FET3 remain low because of destabilization of the mRNAs. Consequently, the respective protein levels also remain low. Such mRNA destabilization is mediated by the general 5'-3' mRNA decay pathway and is independent of the RNA binding protein Cth2. Yeast cells are hypersensitive to peroxides in growth conditions where only the high-affinity reductive pathway is functional for iron assimilation. On the contrary, peroxide does not affect growth when iron uptake occurs exclusively through the non-reductive pathway. This reinforces the idea that upon oxidative stress S. cerevisiae cells redirect iron assimilation through the non-reductive pathway to minimize oxidative damage by the ferrous ions, which are formed during iron import through the Ftr1/Fet3 complexes. The Saccharomyces cerevisiae iron-responsive transcription factor, Aft1, has a well established role in regulating iron homeostasis through the transcriptional induction of iron-regulon genes. However, recent studies have implicated Aft1 in other cellular processes independent of iron regulation such as chromosome stability. In addition, chromosome spreads and two-hybrid data suggest that Aft1 interacts with and co-localizes with kinetochore proteins; however, the cellular implications of this have not been established. Here, we demonstrate that Aft1 associates with the kinetochore complex through Iml3. Furthermore, like Iml3, Aft1 is required for the increased association of cohesin with pericentric chromatin, which is required to resist microtubule tension, and aft1Δ cells display chromosome segregation defects in meiosis. Our work defines a new role for Aft1 in chromosome stability and transmission.

Can PLN mutations lead to dilated cardiomyopathy?

Yes, PLN mutations can lead to dilated cardiomyopathy.

Molecular etiologies of heart failure, an emerging cardiovascular epidemic affecting 4.7 million Americans and costing 17.8 billion health-care dollars annually, remain poorly understood. Here we report that an inherited human dilated cardiomyopathy with refractory congestive heart failure is caused by a domit Arg --> Cys missense mutation at residue 9 (R9C) in phospholamban (PLN), a transmembrane phosphoprotein that inhibits the cardiac sarcoplasmic reticular Ca2+-adenosine triphosphatase (SERCA2a) pump. Transgenic PLN(R9C) mice recapitulated human heart failure with premature death. Cellular and biochemical studies revealed that, unlike wild-type PLN, PLN(R9C) did not directly inhibit SERCA2a. Rather, PLN(R9C) trapped protein kinase A (PKA), which blocked PKA-mediated phosphorylation of wild-type PLN and in turn delayed decay of calcium transients in myocytes. These results indicate that myocellular calcium dysregulation can initiate human heart failure-a finding that may lead to therapeutic opportunities. In human disease and experimental animal models, depressed Ca(2+) handling in failing cardiomyocytes is widely attributed to impaired sarcoplasmic reticulum (SR) function. In mice, disruption of the PLN gene encoding phospholamban (PLN) or expression of domit-negative PLN mutants enhances SR and cardiac function, but effects of PLN mutations in humans are unknown. Here, a T116G point mutation, substituting a termination codon for Leu-39 (L39stop), was identified in two families with hereditary heart failure. The heterozygous individuals exhibited hypertrophy without diminished contractile performance. Strikingly, both individuals homozygous for L39stop developed dilated cardiomyopathy and heart failure, requiring cardiac transplantation at ages 16 and 27. An over 50% reduction in PLN mRNA and no detectable PLN protein were noted in one explanted heart. The expression of recombit PLN-L39stop in human embryonic kidney (HEK) 293 cells and adult rat cardiomyocytes showed no PLN inhibition of SR Ca(2+)-ATPase and the virtual absence of stable PLN expression; where PLN was expressed, it was misrouted to the cytosol or plasma membrane. These findings describe a naturally-occurring loss-of-function human PLN mutation (PLN null). In contrast to reported benefits of PLN ablation in mouse heart failure, humans lacking PLN develop lethal dilated cardiomyopathy. Dilated cardiomyopathy is a disease of the heart muscle resulting from a diverse array of conditions that damages the heart and impairs myocardial function. Heart failure occurs when the heart is unable to pump blood at a rate which can accommodate the heart muscle's metabolic requirements. Several signaling pathways have been shown to be involved in the induction of cardiac disease and heart failure. Many of these pathways are linked to cardiac sarcoplasmic reticulum (SR) Ca cycling directly or indirectly. A large body of evidence points to the central role of abnormal Ca handling by SR proteins, Ca-ATPase pump (SERCA2a) and phospholamban (PLN), in pathophysiological heart conditions, compromising the contractile state of the cardiomyocytes. This review summarizes studies which highlight the key role of these two SR proteins in the regulation of cardiac function, the significance of SERCA2a-PLN interactions using transgenic approaches, and the recent discoveries of human PLN mutations leading to disease states. Finally, we will discuss extrapolation of experimental paradigms generated in animal models to the human condition. AIMS: Familial dilated cardiomyopathy (FDCM) is associated with mutations in more than 10 genes, but genes mutation frequencies and associated clinical features remain largely unknown. Here, we performed a mutation analysis of four genes involved in FDCM in a population of idiopathic DCM. METHODS AND RESULTS: A SSCP and sequencing mutation screening of all the exons coding for beta myosin heavy chain (MYH7 gene), cardiac T troponin (TNNT2 gene), phospholamban (PLN gene), and the cardio-specific exon of metavinculin (VCL gene) were performed in 96 independent patients (54 familial and 42 sporadic). It led to the identification of eight heterozygous mutations, seven new ones in MYH7, and the already described R141W mutation in TNNT2. MYH7 mutations (in five familial and two sporadic cases) substitute residues located either in the head (I201T, T412N, A550V) or tail domains (T1019N, R1193S, E1426K, R1634S) of the protein. DCM was not associated with skeletal myopathy or conduction defects in any patients. Contrasting clinical features were observed between MYH7 and TNNT2 mutations carriers. In MYH7 vs. TNNT2, mean age at diagnosis was late (P<0.03), penetrance was incomplete in adults (56 vs. 100%), and mean age at major cardiac event was higher (P<0.04). CONCLUSION: We have identified seven mutations in MYH7, one in TNNT2, and none in PLN or in the VCL cardio-specific exon. MYH7 appears as the most frequently mutated gene in our FDCM population (approximately 10%), and mutation carriers present with delayed onset, in contrast to TNNT2. The sarcoplasmic reticulum Ca(2+)-cycling proteins are key regulators of cardiac contractility, and alterations in sarcoplasmic reticulum Ca(2+)-cycling properties have been shown to be causal of familial cardiomyopathies. Through genetic screening of dilated cardiomyopathy patients, we identified a previously uncharacterized deletion of arginine 14 (PLN-R14Del) in the coding region of the phospholamban (PLN) gene in a large family with hereditary heart failure. No homozygous individuals were identified. By middle age, heterozygous individuals developed left ventricular dilation, contractile dysfunction, and episodic ventricular arrhythmias, with overt heart failure in some cases. Transgenic mice overexpressing the mutant PLN-R14Del recapitulated human cardiomyopathy exhibiting similar histopathologic abnormalities and premature death. Coexpression of the normal and mutant-PLN in HEK-293 cells resulted in sarcoplasmic reticulum Ca(2+)-ATPase superinhibition. The domit effect of the PLN-R14Del mutation could not be fully removed, even upon phosphorylation by protein kinase A. Thus, by chronic suppression of sarcoplasmic reticulum Ca(2+)-ATPase activity, the nonreversible superinhibitory function of mutant PLN-R14Del may lead to inherited dilated cardiomyopathy and premature death in both humans and mice. Dilated cardiomyopathy (DCM) is a disease of the myocardium, which causes heart failure and premature death. It has been described in humans and several domestic animals. In the Newfoundland dog, DCM is an autosomal domit disease with late onset and reduced penetrance. We analyzed 15 candidate genes for their involvement in DCM in the Newfoundland dog. Polymorphic microsatellite markers and single Nucleotide Polymorphisms were genotyped in 4 families of Newfoundland dogs segregating dilated cardiomyopathy for the genes encoding alpha-cardiac actin (ACTC), caveolin (CAVI), cysteine-rich protein 3 (CSRP3), LIM-domain binding factor 3 (LDB3), desmin (DES), lamin A/C (LMNA), myosin heavy polypeptide 7 (MYH7), delta-sarcoglycan (SGCD), troponin I (TNNTI3), troponin T (TNNT2), alpha-tropomyosin (TPMI), titin (TTN) and vinculin (VCL). A Logarithm of the odds (LOD) score of less than -2.0 in 2-point linkage analysis indicated exclusion of all but 2 genes, encoding CSRP3 and DES. A (LOD) score between -1.5 and -2.0 for CSRP3 and DES makes these genes unlikely causes of DCM in this dog breed. For the phospholamban (PLN) and titin cap (TTN) genes, a direct mutation screening approach was used. DNA sequence analysis of all exons showed no evidence that these genes are involved in DCM in the Newfoundland dog. BACKGROUND: Familial dilated cardiomyopathy is a highly heterogeneous genetic disease. Thus, identification of disease-causing mutations is a challenging and time-consuming task. Genotype-phenotype associations may alleviate identification of the underlying mutation. OBJECTIVE: The purpose of this study was to investigate cardiac phenotypes within a family harboring a familial dilated cardiomyopathy-related mutation in the gene encoding phospholamban. METHODS: Complete genetic and clinical analyses were performed in a family with familial dilated cardiomyopathy due to the PLN-R14Del mutation. Family relatives were studied by ECG, Holter ECG, echocardiography, ECG body surface potential mapping, and cardiac magnetic resoce imaging. RESULTS: A candidate gene approach resulted in identification of a heterozygous deletion of arginine 14 in the gene encoding phospholamban (PLN-R14Del) segregating with dilated cardiomyopathy in the family pedigree. Mutation carriers suffered from familial dilated cardiomyopathy associated with cardiac death between the ages of 26 and 50 years. Interestingly, all adult mutation carriers revealed strikingly attenuated R amplitudes on standard ECG, regardless of the absence or presence of echocardiographic abnormalities. Gadolinium-enhanced cardiac magnetic resoce imaging showed late enhancement in PLN-R14Del carriers with preserved ejection fraction. Late enhancement was regionally related to areas of most pronounced R-amplitude attenuation as assessed by body surface potential mapping. CONCLUSION: Attenuated R amplitudes were identified as an early ECG phenotype in a family with familial dilated cardiomyopathy due to the PLN-R14Del mutation. All adults harboring PLN-R14Del had attenuated R waves irrespective of echocardiographic abnormalities. The study findings suggest a mutation-related remodeling process preceding ventricular dysfunction. BACKGROUND: Phospholamban (PLN) is an effective inhibitor of the sarco(endo)plasmic reticulum Ca(2+)-ATPase, which transports Ca(2+) into the SR lumen, leading to muscle relaxation. A mutation of PLN in which one of the di-arginine residues at positions 13 and 14 was deleted led to a severe, early onset dilated cardiomyopathy. Here we were interested in determining the cellular mechanisms involved in this disease-causing mutation. METHODOLOGY/PRINCIPAL FINDING: Mutations deleting codons for either or both Arg13 or Arg14 resulted in the mislocalization of PLN from the ER. Our data show that PLN is recycled via the retrograde Golgi to ER membrane traffic pathway involving COP-I vesicles, since co-immunoprecipitation assays determined that COP I interactions are dependent on an intact di-arginine motif as PLN RDelta14 did not co-precipitate with COP I containing vesicles. Bioinformatic analysis determined that the di-arginine motif is present in the first 25 residues in a large number of all ER/SR Gene Ontology (GO) annotated proteins. Mutations in the di-arginine motif of the Sigma 1-type opioid receptor, the beta-subunit of the signal recognition particle receptor, and Sterol-O-acyltransferase, three proteins identified in our bioinformatic screen also caused mislocalization of these known ER-resident proteins. CONCLUSION: We conclude that PLN is enriched in the ER due to COP I-mediated transport that is dependent on its intact di-arginine motif and that the N-terminal di-arginine motif may act as a general ER retrieval sequence. The regulatory interaction of phospholamban (PLN) with Ca(2+)-ATPase controls the uptake of calcium into the sarcoplasmic reticulum, modulating heart muscle contractility. A missense mutation in PLN cytoplasmic domain (R9C) triggers dilated cardiomyopathy in humans, leading to premature death. Using a combination of biochemical and biophysical techniques both in vitro and in live cells, we show that the R9C mutation increases the stability of the PLN pentameric assembly via disulfide bridge formation, preventing its binding to Ca(2+)-ATPase as well as phosphorylation by protein kinase A. These effects are enhanced under oxidizing conditions, suggesting that oxidative stress may exacerbate the cardiotoxic effects of the PLN(R9C) mutant. These results reveal a regulatory role of the PLN pentamer in calcium homeostasis, going beyond the previously hypothesized role of passive storage for active monomers. Depressed Ca-handling in cardiomyocytes is frequently attributed to impaired sarcoplasmic reticulum (SR) function in human and experimental heart failure. Phospholamban (PLN) is a key regulator of SR and cardiac function, and PLN mutations in humans have been associated with dilated cardiomyopathy (DCM). We previously reported the deletion of the highly conserved amino acid residue arginine 14 (nucleic acids 39, 40 and 41) in DCM patients. This basic amino acid is important in maintaining the upstream consensus sequence for PKA phosphorylation of Ser 16 in PLN. To assess the function of this mutant PLN, we introduced the PLN-R14Del in cardiac myocytes of the PLN null mouse. Transgenic lines expressing mutant PLN-R14Del at similar protein levels to wild types exhibited no inhibition of the initial rates of oxalate-facilitated SR Ca uptake compared to PLN-knockouts (PLN-KO). The contractile parameters and Ca-kinetics also remained highly stimulated in PLN-R14Del cardiomyocytes, similar to PLN-KO, and isoproterenol did not further stimulate these hyper-contractile basal parameters. Consistent with the lack of inhibition on SR Ca-transport and contractility, confocal microscopy indicated that the PLN-R14Del failed to co-localize with SERCA2a. Moreover, PLN-R14Del did not co-immunoprecipitate with SERCA2a (as did WT-PLN), but rather co-immunoprecipitated with the sarcolemmal Na/K-ATPase (NKA) and stimulated NKA activity. In addition, studies in HEK cells indicated significant fluorescence resoce energy transfer between PLN-R14Del-YFP and NKAα1-CFP, but not with the NKA regulator phospholemman. Despite the enhanced cardiac function in PLN-R14Del hearts (as in PLN-knockouts), there was cardiac hypertrophy (unlike PLN-KO) coupled with activation of Akt and the MAPK pathways. Thus, human PLN-R14Del is misrouted to the sarcolemma, in the absence of endogenous PLN, and alters NKA activity, leading to cardiac remodeling. The sarco(endo)plasmic reticulum calcium ATPase (SERCA) and its regulatory partner phospholamban (PLN) are essential for myocardial contractility. Arg(9) → Cys (R9C) and Arg(14) deletion (R14del) mutations in PLN are associated with lethal dilated cardiomyopathy in humans. To better understand these mutations, we made a series of amino acid substitutions in the cytoplasmic domain of PLN and tested their ability to inhibit SERCA. R9C is a complete loss-of-function mutant of PLN, whereas R14del is a mild loss-of-function mutant. When combined with wild-type PLN to simulate heterozygous conditions, the mutants had a domit negative effect on SERCA function. A series of targeted mutations in this region of the PLN cytoplasmic domain ((8)TRSAIRR(14)) demonstrated the importance of hydrophobic balance in proper PLN regulation of SERCA. We found that Arg(9) → Leu and Thr(8) → Cys substitutions mimicked the behavior of the R9C mutant, and an Arg(14) → Ala substitution mimicked the behavior of the R14del mutant. The results reveal that the change in hydrophobicity resulting from the R9C and R14del mutations is sufficient to explain the loss of function and persistent interaction with SERCA. Hydrophobic imbalance in the cytoplasmic domain of PLN appears to be a predictor for the development and progression of dilated cardiomyopathy. AIMS: To investigate whether phospholamban gene (PLN) mutations underlie patients diagnosed with either arrhythmogenic right ventricular cardiomyopathy (ARVC) or idiopathic dilated cardiomyopathy (DCM). METHODS AND RESULTS: We screened a cohort of 97 ARVC and 257 DCM unrelated index patients for PLN mutations and evaluated their clinical characteristics. PLN mutation R14del was identified in 12 (12 %) ARVC patients and in 39 (15 %) DCM patients. Haplotype analysis revealed a common founder, estimated to be between 575 and 825 years old. A low voltage electrocardiogram was present in 46 % of R14del carriers. Compared with R14del- DCM patients, R14del+ DCM patients more often demonstrated appropriate implantable cardioverter defibrillator discharge (47 % vs. 10 % , P < 0.001), cardiac transplantation (18 % vs. 2 % , P < 0.001), and a family history for sudden cardiac death (SCD) at < 50 years (36 % vs. 16 % , P = 0.007). We observed a similar pattern in the ARVC patients although this was not statistically significant. The average age of 26 family members who died of SCD was 37.7 years. Immunohistochemistry in available myocardial samples revealed absent/depressed plakoglobin levels at intercalated disks in five of seven (71 %) R14del+ ARVC samples, but in only one of nine (11 %) R14del+ DCM samples (P = 0.03). CONCLUSIONS: The PLN R14del founder mutation is present in a substantial number of patients clinically diagnosed with DCM or ARVC. R14del+ patients diagnosed with DCM showed an arrhythmogenic phenotype, and SCD at young age can be the presenting symptom. These findings support the concept of 'arrhythmogenic cardiomyopathy'. AIMS: With more than 40 dilated cardiomyopathy (DCM)-related genes known, genetic analysis of patients with idiopathic DCM is costly and time-consuming. We describe the yield from genetic analysis in DCM patients in a large Dutch cohort. METHODS AND RESULTS: We collected cardiological and neurological evaluations, family screenings, and genetic analyses for 418 index patients with idiopathic DCM. We identified 35 (putative) pathogenic mutations in 82 index patients (20%). The type of DCM influenced the yield, with mutations found in 25% of familial DCM cases, compared with 8% of sporadic DCM cases and 62% of cases where DCM was accompanied by neuromuscular disease. A PLN founder mutation (43 cases) and LMNA mutations (19 cases, 16 different mutations) were most prevalent and often demonstrated a specific phenotype. Other mutations were found in: MYH7, DES, TNNT2, DMD, TPM1, DMPK, SCN5A, SGCB (homozygous), and TNNI3. After a median follow-up of 40 months, the combined outcome of death from any cause, heart transplantation, or maligt ventricular arrhythmias in patients with a mutation was worse than in those without an identified mutation (hazard ratio 2.0, 95% confidence interval 1.4-3.0). This seems to be mainly attributable to a high prevalence of maligt ventricular arrhythmias and end-stage heart failure in LMNA and PLN mutation carriers. CONCLUSION: The yield of identified mutations in DCM index patients with clinical clues, such as associated neuromuscular disease or familial occurrence, is higher compared with those without these clues. For sporadic DCM, specific clinical characteristics may be used to select cases for DNA analysis.

Which is the genetic lesion associated with Huntington’s disease?

The genetic lesion associated with Huntington's disease is a CAG trinucleotide repeat expansion in the HD (or HTT) gene.

Early in 1993, an unstable, expanded trinucleotide repeat in a novel gene of unknown function was identified on HD chromosomes. This discovery unleased a flurry of experimentation that has established the expanded CAG repeat the almost universal cause of the characteristic neurologic symptoms and pathology of this neurodegenerative disorder of midlife onset. The biochemical basis for the specific neuronal loss of HD remains uncertain, but the genetic lesion probably acts via its consequent polyglutamine segment in the protein product, huntingtin. This review will describe the basic parameters of the HD repeat's behavior and the knowledge that has accumulated concerning its potential mechanisms of action.

Is corpus callosum involved in the Mowat–Wilson syndrome?

Yes, agenesis of the corpus callosum is common patients with Mowat–Wilson syndrome. Other characteristic features of Mowat–Wilson syndrome include typical facial features, moderate-to-severe mental retardation, epilepsy and variable congenital malformations, including Hirschsprung disease, genital anomalies, congenital heart disease, and eye defects.

MWS is a multiple congenital anomaly syndrome, first clinically delineated by Mowat et al in 1998. Over 45 cases have now been reported. All patients have typical dysmorphic features in association with severe intellectual disability, and nearly all have microcephaly and seizures. Congenital anomalies, including Hirschsprung disease (HSCR), congenital heart disease, hypospadias, genitourinary anomalies, agenesis of the corpus callosum, and short stature are common. The syndrome is the result of heterozygous deletions or truncating mutations of the ZFHX1B (SIP1) gene on chromosome 2q22. We report a girl who had Hirschsprung disease in association with distinct facial appearance, microcephaly, agenesis of the corpus callosum and mental retardation (Mowat-Wilson syndrome). Mutation analysis of the zinc finger homeo box 1 B (ZFHX1 B) gene revealed a de novo 7 bp deletion (TGGCCCC) at nucleotide 1773 (1773 delTGGCCCC) resulting in a frameshift and leading to a termination codon at amino acid residue 604 (604 X) in exon 8 C. The zinc finger homeo box 1 B (Smad interacting protein-1) is a transcription corepressor of Smad target genes with functions in the patterning of neural crest derived cells, CNS, and midline structures. Mutations in ZFHX1 B can lead to neurological disorders in addition to dysmorphic features, megacolon, and other malformations. Mowat-Wilson Syndrome is a recently delineated mental retardation syndrome usually associated with multiple malformations and a recognizable facial phenotype caused by defects of the transcriptional repressor ZFHX1B. To address the question of clinical and mutational variability, we analysed a large number of patients with suspected Mowat-Wilson Syndrome (MWS). Without prior knowledge of their mutational status, 70 patients were classified into "typical MWS", "ambiguous" and "atypical" groups according to their facial phenotype. Using FISH, qPCR and sequencing, ZFHX1B deletions, splice site or truncating mutations were detected in all 28 patients classified as typical MWS. No ZFHX1B defect was apparent in the remaining 15 cases with ambiguous facial features or in the 27 atypical patients. Genotype-phenotype analysis confirmed that ZFHX1B deletions and stop mutations result in a recognizable facial dysmorphism with associated severe mental retardation and variable malformations such as Hirschsprung disease and congenital heart defects. Our findings indicate that structural eye anomalies such as microphthalmia should be considered as part of the MWS spectrum. We also show that agenesis of the corpus callosum and urogenital anomalies (especially hypospadias) are significant positive predictors of a ZFHX1B defect. Based on our observation of affected siblings and the number of MWS cases previously reported, we suggest a recurrence risk of around 1%. The lack of missense mutations in MWS and MWS-like patients suggests there may be other, as yet unrecognized phenotypes, associated with missense mutations of this transcription factor. Mowat-Wilson syndrome (MWS) is a relatively newly described multiple congenital anomaly/mental retardation syndrome. Haploinsufficiency of a gene termed ZFHX1B (also known as SIP1) on chromosome 2 is responsible for this condition, and clinical genetic testing for MWS recently became available. The majority of reports in the literature originate from Northern Europe and Australia. Here we report our clinical experience with 12 patients diagnosed with MWS within a 2-year period of time in the United States, with particular emphasis on clinical characteristics and management strategies. Individuals with this condition have characteristic facial features, including microcephaly, hypertelorism, medially flared and broad eyebrows, prominent columella, pointed chin, and uplifted earlobes, which typically prompt the clinician to consider the diagnosis. Medical issues in our cohort of patients included seizures (75%) with no predeliction for any particular seizure type; agenesis of the corpus callosum (60% of our patients studied); congenital heart defects (75%), particularly involving the pulmonary arteries and/or valves; hypospadias (55% of males); severely impaired or absent speech (100% of individuals over 1 year of age) with relatively spared receptive language; and Hirschsprung disease (50%) or chronic constipation (25%). The incidence of MWS is unknown, but based on the number of patients identified in a short period of time within the US, it is likely greatly under recognized. MWS should be considered in any individual with severely impaired or absent speech, especially in the presence of seizures and anomalies involving the pulmonary arteries (particularly pulmonary artery sling) or pulmonary valves. Mowat-Wilson syndrome (MWS) is a recently delineated mental retardation (MR)-multiple congenital anomaly syndrome, characterized by typical facies, severe MR, epilepsy, and variable congenital malformations, including Hirschsprung disease (HSCR), genital anomalies, congenital heart disease (CHD), and agenesis of the corpus callosum (ACC). It is caused by de novo heterozygous mutations or deletions of the ZFHX1B gene located at 2q22. ZFHX1B encodes Smad-interacting protein-1 (SMADIP1 or SIP1), a transcriptional corepressor involved in the transforming growth factor-beta signaling pathway. It is a highly evolutionarily conserved gene, widely expressed in embryological development. Over 100 mutations have been described in patients with clinically typical MWS, who almost always have whole gene deletions or truncating mutations (nonsense or frameshift) of ZFHX1B, suggesting that haploinsufficiency is the basis of MWS pathology. No obvious genotype-phenotype correlation could be identified so far, but atypical phenotypes have been reported with missense or splice mutations in the ZFHX1B gene. In this work we describe 40 novel mutations and we summarize the various mutational reports published since the identification of the causative gene. Mowat-Wilson syndrome (MWS) is a multiple congenital anomaly syndrome characterized by a distinct facial phenotype (high forehead, frontal bossing, large eyebrows, medially flaring and sparse in the middle part, hypertelorism, deep set but large eyes, large and uplifted ear lobes, with a central depression, saddle nose with prominent rounded nasal tip, prominent columella, open mouth, with M-shaped upper lip, frequent smiling, and a prominent but narrow and triangular pointed chin), moderate-to-severe intellectual deficiency, epilepsy and variable congenital malformations including Hirschsprung disease (HSCR), genitourinary anomalies (in particular hypospadias in males), congenital heart defects, agenesis of the corpus callosum and eye anomalies. The prevalence of MWS is currently unknown, but 171 patients have been reported so far. It seems probable that MWS is under-diagnosed, particularly in patients without HSCR. MWS is caused by heterozygous mutations or deletions in the Zinc finger E-box-binding homeobox 2 gene, ZEB2, previously called ZFHX1B (SIP1). To date, over 100 deletions/mutations have been reported in patients with a typical phenotype; they are frequently whole gene deletions or truncating mutations, suggesting that haploinsufficiency is the main pathological mechanism. Studies of genotype-phenotype analysis show that facial gestalt and delayed psychomotor development are constant clinical features, while the frequent and severe congenital malformations are variable. In a small number of patients, unusual mutations can lead to an atypical phenotype. The facial phenotype is particularly important for the initial clinical diagnosis and provides the hallmark warranting ZEB2 mutational analysis, even in the absence of HSCR. The majority of MWS cases reported so far were sporadic, therefore the recurrence risk is low. Nevertheless, rare cases of sibling recurrence have been observed. Congenital malformations and seizures require precocious clinical investigation with intervention of several specialists (including neonatologists and pediatricians). Psychomotor development is delayed in all patients, therefore rehabilitation (physical therapy, psychomotor and speech therapy) should be started as soon as possible. Agenesis of the corpus callosum (ACC) is among the most frequent human brain malformations with an incidence of 0.5-70 in 10,000. It is a heterogeneous condition, for which several different genetic causes are known, for example, ACC as part of monogenic syndromes or complex chromosomal rearrangements. We systematically evaluated the data of 172 patients with documented corpus callosum abnormalities in the records, and 23 patients with chromosomal rearrangements known to be associated with corpus callosum changes. All available neuroimaging data, including CT and MRI, were re-evaluated following a standardized protocol. Whenever feasible chromosome and subtelomere analyses as well as molecular genetic testing were performed in patients with disorders of the corpus callosum in order to identify a genetic diagnosis. Our results showed that 41 patients with complete absence (agenesis of the corpus callosum-ACC) or partial absence (dysgenesis of the corpus callosum-DCC) were identified. Out of these 28 had ACC, 13 had DCC. In 11 of the 28 patients with ACC, the following diagnoses could be established: Mowat-Wilson syndrome (n = 2), Walker-Warburg syndrome (n = 1), oro-facial-digital syndrome type 1 (n = 1), and chromosomal rearrangements (n = 7), including a patient with an apparently balanced reciprocal translocation, which led to the disruption and a predicted loss of function in the FOXG1B gene. The cause of the ACC in 17 patients remained unclear. In 2 of the 13 patients with DCC, unbalanced chromosomal rearrangements could be detected (n = 2), while the cause of DCC in 11 patients remained unclear. In our series of cases a variety of genetic causes of disorders of the corpus callosum were identified with cytogenetic anomalies representing the most common underlying etiology. Mowat-Wilson syndrome (MWS; OMIM #235730) is a genetic condition caused by heterozygous mutations or deletions of the ZEB2 gene, and characterized by typical face, moderate-to-severe mental retardation, epilepsy, Hirschsprung disease, and multiple congenital anomalies, including genital anomalies (particularly hypospadias in males), congenital heart defects, agenesis of the corpus callosum, and eye defects. Since the first delineation by Mowat et al. [Mowat et al. (1998); J Med Genet 35:617-623], approximately 179 patients with ZEB2 mutations, deletions or cytogenetic abnormalities have been reported primarily from Europe, Australia and the United States. Genetic defects include chromosome 2q21-q23 microdeletions (or different chromosome rearrangements) in few patients, and ZEB2 mutations in most. We report on clinical and genetic data from 19 Italian patients, diagnosed within the last 5 years, including six previously published, and compare them with patients already reported. The main purpose of this review is to underline a highly consistent phenotype and to highlight the phenotypic evolution occurring with age, particularly of the facial characteristics. The prevalence of MWS is likely to be underestimated. Knowledge of the phenotypic spectrum of MWS and of its changing phenotype with age can improve the detection rate of this condition. Mowat-Wilson syndrome is a genetic condition characterized by a recognizable facial phenotype in addition to moderate to severe cognitive disability with severe speech impairment and variable multiple congenital anomalies. The anomalies may include Hirschsprung disease, heart defects, structural eye anomalies including microphthalmia, agenesis of the corpus callosum, and urogenital anomalies. Microcephaly, seizure disorder and constipation are common. All typical cases result from haploinsufficiency of the ZEB2 (also known as ZFHX1B or SIP-1) gene, with over 100 distinct mutations now described. Approximately 80% of patients have a nonsense or frameshift mutation detectable by sequencing, with the rest having gross deletions necessitating a dosage sensitive assay. Here we report on the results of comprehensive molecular testing for 27 patients testing positive for MWS. Twenty-one patients had a nonsense, frameshift, or splice site mutation identified by sequencing; 14 of which localized to exon 8 and 17 of which are novel. Six patients had deletions in the ZEB2 gene, including two novel partial gene deletions. This report, the first such analysis in North American patients, adds to the growing list of both novel pathogenic mutations associated with MWS, as well as other variants in the ZEB2 gene. In addition, we suggest an economical testing strategy. Mowat-Wilson syndrome (MWS) is an autosomal domit intellectual disability syndrome characterised by unique facial features and congenital anomalies such as Hirschsprung disease, congenital heart defects, corpus callosum agenesis and urinary tract anomalies. Some cases also present epilepsy, growth retardation and microcephaly. The syndrome is caused by mutations or deletions of the ZEB2 gene at chromosome 2q22-q23. MWS was first described in 1998 and until now approximately 180 cases have been reported worldwide. We report the first three molecularly confirmed Danish cases with MWS. Mowat-Wilson syndrome is a mental retardation-multiple congenital anomaly syndrome characterized by a typical facies, developmental delay, epilepsy, and variable congenital malformations, including Hirschsprung disease, urogenital anomalies, congenital heart disease, and agenesis of the corpus callosum. This disorder is sporadic and is caused by heterozygous mutations or deletions of the ZFHX1B gene located in the 2q22 region. We report here the first Moroccan patient, born to consanguineous parents, with Mowat-Wilson syndrome, due to a de novo, unreported mutation of the ZFHX1B gene. Mowat-Wilson syndrome is a genetic disorder characterized by a distinct facial appearance, moderate-to-severe mental retardation, microcephaly, agenesis of the corpus callosum, Hirschsprung disease, congenital heart disease, and genital anomalies. Ophthalmological abnormalities have been rarely described in patients with this condition which is caused by mutations in the ZEB2 gene. We report a 9-year-old female with this syndrome who has severe ocular abnormalities including bilateral microphthalmia, cataract, and retinal aplasia. Mowat-Wilson syndrome (OMIM 235730) is a genetic condition characterized by moderate-to-severe intellectual disability, a recognizable facial phenotype, and multiple congenital anomalies. The striking facial phenotype in addition to other features such as severely impaired speech, hypotonia, microcephaly, short stature, seizures, corpus callosum agenesis, congenital heart defects, hypospadias, and Hirschsprung disease are particularly important clues for the initial clinical diagnosis. All molecularly confirmed cases with typical MWS have a heterozygous loss-of-function mutation in the zinc finger E-box protein 2 (ZEB2) gene, also called SIP1 (Smad-interacting protein 1) and ZFHX1B, suggesting that haploinsufficiency is the main pathological mechanism. Approximately 80% of mutations are nonsense and frameshift mutations (small insertions or deletions). About half of these mutations are located in exon eight. Here, we report the first Indonesian patient with Mowat-Wilson syndrome confirmed by molecular analysis. Mowat-Wilson syndrome (MWS) is a severe intellectual disability (ID)-distinctive facial gestalt-multiple congenital anomaly syndrome, commonly associating microcephaly, epilepsy, corpus callosum agenesis, conotruncal heart defects, urogenital malformations and Hirschsprung disease (HSCR). MWS is caused by de novo heterozygous mutations in the ZEB2 gene. The majority of mutations lead to haplo-insufficiency through premature stop codons or large gene deletions. Only three missense mutations have been reported so far; none of which resides in a known functional domain of ZEB2. In this study, we report and analyze the functional consequences of three novel missense mutations, p.Tyr1055Cys, p.Ser1071Pro and p.His1045Arg, identified in the highly conserved C-zinc-finger (C-ZF) domain of ZEB2. Patients' phenotype included the facial gestalt of MWS and moderate ID, but no microcephaly, heart defects or HSCR. In vitro studies showed that all the three mutations prevented binding and repression of the E-cadherin promoter, a characterized ZEB2 target gene. Taking advantage of the zebrafish morphant technology, we performed rescue experiments using wild-type (WT) and mutant human ZEB2 mRNAs. Variable, mutation-dependent, embryo rescue, correlating with the severity of patients' phenotype, was observed. Our data provide evidence that these missense mutations cause a partial loss of function of ZEB2, suggesting that its role is not restricted to repression of E-cadherin. Functional domains other than C-ZF may play a role in early embryonic development. Finally, these findings broaden the clinical spectrum of ZEB2 mutations, indicating that MWS ought to be considered in patients with lesser degrees of ID and a suggestive facial gestalt, even in the absence of congenital malformation. Mowat-Wilson syndrome (MWS) is a genetic disease caused by heterozygous mutations or deletions of the ZEB2 gene rarely diagnosed prenatally and with little fetal description reported. It is mainly characterized by moderate-to-severe intellectual disability, epilepsy, facial dysmorphism and various malformations including Hirschsprung disease and corpus callosum anomalies. Here we report a fetal case of MWS well described, suspected at standard autopsy. The association of a corpus callosum hypoplasia with a histological Hirschsprung disease and a typical facial gestalt allowed the guiding of genetic testing. Classical fetopathological examination still keeps indications in cases of syndromic association in the era of virtual autopsy. The smooth identification and low-cost production of highly specific agents that interfere with signaling cascades by targeting an active domain in surface receptors, cytoplasmic and nuclear effector proteins, remain important challenges in biomedical research. We propose that peptide aptamers can provide a very useful and new alternative for interfering with protein-protein interactions in intracellular signal transduction cascades, including those emanating from activated receptors for growth factors. By their targeting of short, linear motif type of interactions, peptide aptamers have joined nucleic acid aptamers for use in signaling studies because of their ease of production, their stability, their high specificity and affinity for individual target proteins, and their use in high-throughput screening protocols. Furthermore, they are entering clinical trials for treatment of several complex, pathological conditions. Here, we present a brief survey of the use of aptamers in signaling pathways, in particular of polypeptide growth factors, starting with the published as well as potential applications of aptamers targeting Epidermal Growth Factor Receptor signaling. We then discuss the opportunities for using aptamers in other complex pathways, including Wnt/β-catenin, and focus on Transforming Growth Factor-β/Smad family signaling. Mowat-Wilson syndrome is a genetic disease caused by heterozygous mutations or deletions of the zinc finger E-box-binding homeobox 2 (ZEB2) gene. The syndrome is characterized by typical facial features, moderate-to-severe mental retardation, epilepsy and variable congenital malformations, including Hirschsprung disease, genital anomalies, congenital heart disease, agenesis of the corpus callosum, and eye defects. The prevalence of Mowat-Wilson syndrome is currently unknown, but it seems that Mowat-Wilson syndrome is underdiagnosed, particularly in patients without Hirschsprung disease. We report here the first Egyptian case of Mowat-Wilson syndrome who was conceived by intracytoplasmic sperm injection. The patient manifested bilateral sensorineural hearing loss--a new feature not previously reported in cases of Mowat-Wilson syndrome. This report describes the first Egyptian patient of Mowat-Wilson syndrome who was conceived after intracytoplasmic sperm injection, and provides a new evidence for the inclusion of deafness among the congenital defects of the syndrome. Primary asplenia is a rare condition with poorly known etiology. Mowat-Wilson syndrome (MWS) is characterized by typical facial dysmorphisms, intellectual disability, microcephaly, epilepsy and the possible presence of internal organ malformations. It is caused by heterozygous mutations or deletions in the ZEB2 gene. Nearly 180 patients have been reported to date, but only one with asplenia. We report here spleen hypo/aplasia in 4 out of 6 MWS patients, with severe infectious complications for 3 of them. Our report shows that spleen hypo/aplasia is part of the MWS phenotype and makes ZEB2 a possible candidate gene for primary asplenia.

Which histone modification discriminates between active and poised enhancers?

Monomethylation of histone H3 on Lys 4 (H3K4me1) and acetylation of histone H3 on Lys 27 (H3K27ac) are histone modifications that are highly enriched over the body of actively transcribed genes and on enhancers.

Developmental programs are controlled by transcription factors and chromatin regulators, which maintain specific gene expression programs through epigenetic modification of the genome. These regulatory events at enhancers contribute to the specific gene expression programs that determine cell state and the potential for differentiation into new cell types. Although enhancer elements are known to be associated with certain histone modifications and transcription factors, the relationship of these modifications to gene expression and developmental state has not been clearly defined. Here we interrogate the epigenetic landscape of enhancer elements in embryonic stem cells and several adult tissues in the mouse. We find that histone H3K27ac distinguishes active enhancers from inactive/poised enhancer elements containing H3K4me1 alone. This indicates that the amount of actively used enhancers is lower than previously anticipated. Furthermore, poised enhancer networks provide clues to unrealized developmental programs. Finally, we show that enhancers are reset during nuclear reprogramming. Epigenetic regulation of gene enhancer elements is important for establishing and maintaining the identity of cells. Gene enhancer elements are thought to exist in either active or poised states distinguishable by chromatin features, but a complete understanding of the regulation of enhancers is lacking. Here, by using mouse embryonic stem cells and their differentiated derivatives, as well as terminally differentiated cells, we report the coexistence of multiple, defined classes of enhancers that serve distinct cellular functions. Specifically, we found that active enhancers can be subclassified based on varying levels of H3K4me1, H3K27ac, and H3K36me3 and the pSer2/5 forms of RNA polymerase II. The abundance of these histone modifications positively correlates with the expression of associated genes and cellular functions consistent with the identity of the cell type. Poised enhancers can also be subclassified based on presence or absence of H3K27me3 and H3K9me3, conservation, genomic location, expression levels of associated genes, and predicted function of associated genes. These findings not only refine the repertoire of histone modifications at both active and poised gene enhancer elements but also raise the possibility that enhancers associated with distinct cellular functions are partitioned based on specific combinations of histone modifications. The regions bound by sequence-specific transcription factors can be highly variable across different cell types despite the static nature of the underlying genome sequence. This has been partly attributed to changes in chromatin accessibility, but a systematic picture has been hindered by the lack of large-scale data sets. Here, we use 456 binding experiments for 119 regulators and 84 chromatin maps generated by the ENCODE in six human cell types, and relate those to a global map of regulatory motif instances for these factors. We find specific and robust chromatin state preferences for each regulator beyond the previously reported open-chromatin association, suggesting a much richer chromatin landscape beyond simple accessibility. The preferentially bound chromatin states of regulators were enriched for sequence motifs of regulators relative to all states, suggesting that these preferences are at least partly encoded by the genomic sequence. Relative to all regions bound by a regulator, however, regulatory motifs were surprisingly depleted in the regulator's preferentially bound states, suggesting additional non-sequence-specific binding beyond the level predicted by the regulatory motifs. Such permissive binding was largely restricted to open-chromatin regions showing histone modification marks characteristic of active enhancer and promoter regions, whereas open-chromatin regions lacking such marks did not show permissive binding. Lastly, the vast majority of cobinding of regulator pairs is predicted by the chromatin state preferences of individual regulators. Overall, our results suggest a joint role of sequence motifs and specific chromatin states beyond mere accessibility in mediating regulator binding dynamics across different cell types. Chromatin regions with different states usually harbor distinct epigenetic information, through which gene expression is regulated. Recent studies using mammalian cells showed that a chromatin state signature is associated with active developmental enhancers, defined by high levels of histone H3 lysine 27 acetylation (H3K27ac) and strong depletion of H3K27 trimethylation (H3K27me3). These findings also imply that active enhancers may play a role in creating a chromatin state by changing histone modification markers, which in turn affects gene expression. To explore whether an active enhancer in plants affect histone modifications, we investigated the cauliflower mosaic virus 35S enhancer (35Senh) for understanding its action model in Arabidopsis. We report that the 35Senh has a function to change the histone modification pattern at its presenting loci, by characterization of the 35Senh activated BREVIPEDICELLUS (BP) silencing lines and the randomly selected 35Senh activation tagging lines. By analyzing histone modification markers reflecting the plant chromatin state, we show that the 35Senh is generally correlated with the reduced level of H3K27me3 and the increased level of H3K4me3 at the insertion loci. Our data are consistent with those in mammals and suggest that the enhancer sequence correlating with the active chromatin state signature may be generally present in the eukaryotic kingdom. Enhancers play a pivotal role in regulating the transcription of distal genes. Although certain chromatin features, such as the histone acetyltransferase P300 and the histone modification H3K4me1, indicate the presence of enhancers, only a fraction of enhancers are functionally active. Individual chromatin marks, such as H3K27ac and H3K27me3, have been identified to distinguish active from inactive enhancers. However, the systematic identification of the most informative single modification, or combination thereof, is still lacking. Furthermore, the discovery of enhancer RNAs (eRNAs) provides an alternative approach to directly predicting enhancer activity. However, it remains challenging to link chromatin modifications to eRNA transcription. Herein, we develop a logistic regression model to unravel the relationship between chromatin modifications and eRNA synthesis. We perform a systematic assessment of 24 chromatin modifications in fetal lung fibroblast and demonstrate that a combination of four modifications is sufficient to accurately predict eRNA transcription. Furthermore, we compare the ability of eRNAs and H3K27ac to discriminate enhancer activity. We demonstrate that eRNA is more indicative of enhancer activity. Finally, we apply our fibroblast trained model to six other cell-types and successfully predict eRNA synthesis. Thus, we demonstrate the learned relationships are general and independent of cell-type. We provided a powerful tool to identify active enhancers and reveal the relationship between chromatin modifications, eRNA production and enhancer activity. The bivalent hypothesis posits that genes encoding developmental regulators required for early lineage decisions are poised in stem/progenitor cells by the balance between a repressor histone modification (H3K27me3), mediated by the Polycomb Repressor Complex 2 (PRC2), and an activator modification (H3K4me3). In this study, we test whether this mechanism applies equally to genes that are not required until terminal differentiation. We focus on the RE1 Silencing Transcription Factor (REST) because it is expressed highly in stem cells and is an established global repressor of terminal neuronal genes. Elucidation of the REST complex, and comparison of chromatin marks and gene expression levels in control and REST-deficient stem cells, shows that REST target genes are poised by a mechanism independent of Polycomb, even at promoters which bear the H3K27me3 mark. Specifically, genes under REST control are actively repressed in stem cells by a balance of the H3K4me3 mark and a repressor complex that relies on histone deacetylase activity. Thus, chromatin distinctions between pro-neural and terminal neuronal genes are established at the embryonic stem cell stage by two parallel, but distinct, repressor pathways. Myelination of the peripheral nervous system is required for axonal function and long term stability. After peripheral nerve injury, Schwann cells transition from axon myelination to a demyelinated state that supports neuronal survival and ultimately remyelination of axons. Reprogramming of gene expression patterns during development and injury responses is shaped by the actions of distal regulatory elements that integrate the actions of multiple transcription factors. We used ChIP-seq to measure changes in histone H3K27 acetylation, a mark of active enhancers, to identify enhancers in myelinating rat peripheral nerve and their dynamics after demyelinating nerve injury. Analysis of injury-induced enhancers identified enriched motifs for c-Jun, a transcription factor required for Schwann cells to support nerve regeneration. We identify a c-Jun-bound enhancer in the gene for Runx2, a transcription factor induced after nerve injury, and we show that Runx2 is required for activation of other induced genes. In contrast, enhancers that lose H3K27ac after nerve injury are enriched for binding sites of the Sox10 and early growth response 2 (Egr2/Krox20) transcription factors, which are critical determits of Schwann cell differentiation. Egr2 expression is lost after nerve injury, and many Egr2-binding sites lose H3K27ac after nerve injury. However, the majority of Egr2-bound enhancers retain H3K27ac, indicating that other transcription factors maintain active enhancer status after nerve injury. The global epigenomic changes in H3K27ac deposition pinpoint dynamic changes in enhancers that mediate the effects of transcription factors that control Schwann cell myelination and peripheral nervous system responses to nerve injury.

What are the properties of super-enhancers?

Super-enhancers differ from typical enhancers in size, transcription factor density and content, ability to activate transcription, and sensitivity to perturbation. Defined by their magnitude of size, transcription factor density, and binding of transcriptional machinery, super-enhancers have been associated with genes driving cell differentiation. In this respect, the super-enhancer definition is useful in identifying regulatory elements likely to control genes important for cell type specification. Super-enhancers thus play key roles in the control of mammalian cell identity.

Super-enhancers are large clusters of transcriptional enhancers that drive expression of genes that define cell identity. Improved understanding of the roles that super-enhancers play in biology would be afforded by knowing the constellation of factors that constitute these domains and by identifying super-enhancers across the spectrum of human cell types. We describe here the population of transcription factors, cofactors, chromatin regulators, and transcription apparatus occupying super-enhancers in embryonic stem cells and evidence that super-enhancers are highly transcribed. We produce a catalog of super-enhancers in a broad range of human cell types and find that super-enhancers associate with genes that control and define the biology of these cells. Interestingly, disease-associated variation is especially enriched in the super-enhancers of disease-relevant cell types. Furthermore, we find that cancer cells generate super-enhancers at oncogenes and other genes important in tumor pathogenesis. Thus, super-enhancers play key roles in human cell identity in health and in disease. It is becoming increasingly clear that transcription factors operate in complex networks through thousands of genomic binding sites, many of which bind several transcription factors. However, the extent and mechanisms of crosstalk between transcription factors at these hotspots remain unclear. Using a combination of advanced proteomics and genomics approaches, we identify ∼12,000 transcription factor hotspots (∼400 bp) in the early phase of adipogenesis, and we find evidence of both simultaneous and sequential binding of transcription factors at these regions. We demonstrate that hotspots are highly enriched in large super-enhancer regions (several kilobases), which drive the early adipogenic reprogramming of gene expression. Our results indicate that cooperativity between transcription factors at the level of hotspots as well as super-enhancers is very important for enhancer activity and transcriptional reprogramming. Thus, hotspots and super-enhancers constitute important regulatory hubs that serve to integrate external stimuli on chromatin. Enhancers are critical genomic elements that define cellular and functional identity through the spatial and temporal regulation of gene expression. Recent studies suggest that key genes regulating cell type-specific functions reside in enhancer-dense genomic regions (i.e., super enhancers, stretch enhancers). Here we report that enhancer RNAs (eRNAs) identified by global nuclear run-on sequencing are extensively transcribed within super enhancers and are dynamically regulated in response to cellular signaling. Using Toll-like receptor 4 (TLR4) signaling in macrophages as a model system, we find that transcription of super enhancer-associated eRNAs is dynamically induced at most of the key genes driving innate immunity and inflammation. Unexpectedly, genes repressed by TLR4 signaling are also associated with super enhancer domains and accompanied by massive repression of eRNA transcription. Furthermore, we find each super enhancer acts as a single regulatory unit within which eRNA and genic transcripts are coordinately regulated. The key regulatory activity of these domains is further supported by the finding that super enhancer-associated transcription factor binding is twice as likely to be conserved between human and mouse than typical enhancer sites. Our study suggests that transcriptional activities at super enhancers are critical components to understand the dynamic gene regulatory network.

What is the inheritance pattern of Li–Fraumeni syndrome?

Li-Fraumeni syndrome shows autosomal dominant inheritance.

Li-Fraumeni syndrome (LFS) is a highly penetrant, autosomal domit, human familial cancer predisposition. Although a key role for the tumor suppressor p53 has been implicated in LFS, the genetic and cellular mechanisms underpinning this disease remain unknown. Therefore, modeling LFS in a vertebrate system that is accessible to both large-scale genetic screens and in vivo cell biological studies will facilitate the in vivo dissection of disease mechanisms, help identify candidate genes, and spur the discovery of therapeutic compounds. Here, we describe a forward genetic screen in zebrafish embryos that was used to identify LFS candidate genes, which yielded a p53 mutant (p53(I166T)) that as an adult develops tumors, predomitly sarcomas, with 100% penetrance. As in humans with LFS, tumors arise in heterozygotes and display loss of heterozygosity (LOH). This report of LOH indicates that Knudson's two-hit hypothesis, a hallmark of human autosomal domit cancer syndromes, can be modeled in zebrafish. Furthermore, as with some LFS mutations, the zebrafish p53(I166T) allele is a loss-of-function allele with domit-negative activity in vivo. Additionally, we demonstrate that the p53 regulatory pathway, including Mdm2 regulation, is evolutionarily conserved in zebrafish, providing a bona fide biological context in which to systematically uncover novel modifier genes and therapeutic agents for human LFS.

Which pituitary adenoma is common cause of infertility is women?

Prolactinoma is a pituitary adenoma that is strongly associated with infertility in women mainly due to increased prolactin secretion causing hyperprolactinemia. Other pituitary lesions can also be associated with infertility.

Two hyperprolactinemic infertile women, one with and one without a pituitary adenoma, who were resistant to bromocriptine treatment, were treated orally with Hachimijiogan, a Chinese herbal medicine. This treatment reduced the serum prolactin level, resulting in a normal ovulatory cycle and pregcy, without side effects. Results in 136 hyperprolactinaemic women who presented with infertility, amenorrhoea, menstrual irregularities and/or galactorrhoea are reported. There was radiographic evidence of pituitary microadenoma in 21 (15.4%) patients and 5 (3.7%) had macroadenoma. Four patients were taking antidepressants, 2 antihypertensive drugs and 7 had taken oral contraceptives for a period of 6 months to 5 years. The remaining patients had no obvious cause for elevated prolactin levels. Patients with pituitary adenoma had a significantly higher (p less than 0.001) baseline serum prolactin level (182 +/- 4.6 ng/ml) than those with no adenoma (59.2 +/- 4.2 ng/ml). All patients in the study were treated with bromocriptine (2.5-10 mg) to normalize serum prolactin or to achieve a pregcy. The patients without an adenoma required a significantly smaller dose of bromocriptine (2.5-5.0 mg) (p less than 0.005) than those with an adenoma. Galactorrhoea disappeared in all 64 patients within 2-4 months of treatment, sixty-six (71%) of the 93 patients who desired pregcy achieved it within 3 to 8 months of bromocriptine therapy; 32 of these patients received additional treatment with clomiphene and human chorionic gonadotrophins for induction of ovulation. In the remaining 70 patients menstruation became regular and ovulation was evident in 40% of them. There was no significant difference in the pregcy rate between the patients with or without pituitary adenoma. Similarly, presence of galactorrhoea or a high level of prolactin did not influence the pregcy rate. No complications were observed during pregcy related to pituitary adenomas; 8 (12%) pregcies ended in first trimester abortion. No lethal congenital fetal abnormalities were observed in the patients treated with bromocriptine.(ABSTRACT TRUNCATED AT 250 WORDS) Infertility caused by hyperprolactinemic amenorrhea may be complicated by pituitary adenoma. In a group of 36 women with amenorrhoea-hyperprolactinemia-syndrome were 15 infertility-patients. 10 of them had prolactin levels above 100 ng/ml. In 6 patients a prolactinoma was removed microsurgically. In every case further treatment was necessary to get normal cycles. 8 of these 10 infertility-patients became pregt. Hyperprolactinemia is the most common endocrine disorder of the hypothalamic-pituitary axis. While it can occur in men, it occurs more commonly in women. The prevalence of hyperprolactinemia ranges from 0.4% in an unselected normal adult population to as high as 9-17% in women with reproductive disorders. There are many possible causes of hyperprolactinemia, falling into three general categories: physiologic, pharmacologic and pathologic. When specific treatable underlying causes have been eliminated and in cases of severe hyperprolactinemia, the most likely cause is a prolactin (PRL)-secreting pituitary adenoma. Microadenomas should be treated medically, with a dopamine agonist, if there is an indication for therapy (such as amenorrhea, infertility or bothersome galactorrhea). If there is no indication for therapy, microadenomas may be followed conservatively, as growth is uncommon. Macroadenomas may grow larger; medical therapy is recommended initially, with neurosurgical evaluation reserved for specific clinical situations, such as failure of medical therapy and evidence of mass effect despite medical therapy. In the United States, the dopamine agonists indicated for treatment of hyperprolactinemia are bromocriptine and cabergoline. Bromocriptine is usually given once or twice daily, while cabergoline has a long duration of action and is given once or twice weekly. Results of comparative studies indicate that cabergoline is clearly superior to bromocriptine in efficacy (PRL suppression, restoration of gonadal function) and tolerability. Prolactin is a polypeptide hormone essential for lactation. Its production in the lactotroph cells of the anterior pituitary is regulated primarily by the inhibitory action of hypothalamic dopamine. Hyperprolactinemia is the most common endocrine disorder of the hypothalamic-pituitary axis, occurring mostly in women and presenting most commonly with amenorrhea and galactorrhea. Causes of hyperprolactinemia include physiologic, pharmacologic and pathologic factors; pituitary adenoma is a common pathologic cause. Women may present with decreased libido, infertility, oligomenorrhea/amenorrhea and galactorrhea. Men may present with decreased libido, infertility, gynecomastia or impotence. In the absence of an identifiable and treatable underlying cause, hyperprolactinemia is generally treated with dopamine agonist medications. OBJECTIVE: To report a case of a gonadotroph adenoma diagnosed after a dramatic increase in estradiol level and ovarian hyperstimulation in response to a gonadotropin-releasing hormone agonist. DESIGN: Case report. SETTING: Outpatient practice and university hospital. PATIENT(S): A 35-year-old woman who presented with infertility, amenorrhea, and an elevated basal estradiol concentration. INTERVENTION(S): Ultrasonography, laparoscopy, endocrinologic assays, magnetic resoce imaging, transsphenoidal surgery, and immunocytochemical staining. MAIN OUTCOME MEASURE(S): Ultrasonography and laparoscopy demonstrated bilaterally enlarged ovaries containing multiple preovulatory follicles, similar in appearance in those women undergoing controlled ovarian hyperstimulation with exogenous FSH. The serum estradiol level was moderately elevated, the FSH level was within the normal range, and LH was suppressed. Administration of leuprolide acetate resulted in very elevated estradiol concentrations and even larger ovarian cysts. Magnetic resoce imaging demonstrated a sellar mass. Examination of the tissue excised by transsphenoidal excision of the mass showed a pituitary adenoma that stained strongly for FSH. RESULT(S): Regular menses resumed soon after excision of the gonadotroph adenoma, followed by a spontaneous pregcy. CONCLUSIONS: Gonadotroph adenoma should be suspected in a reproductive age woman with oligomenorrhea or amenorrhea, infertility, multiple preovulatory follicles, and a persistently elevated serum estradiol concentration. Exacerbation of the ovarian hyperstimulation in response to a gonadotropin-releasing hormone agonist in this setting also strongly suggests a gonadotroph adenoma but can be avoided by recognizing the presenting features of this condition. Prolactinoma is the most common secreting pituitary adenoma. It is typically diagnosed in women of reproductive age and is common cause of infertility. Currently the treatment of choice is pharmacotherapy with dopamine agonists, whereas surgical treatment is reserved for a selected group of patients. Pituitary-tumor apoplexy is a rare, life-threatening condition associated with significant morbidity and mortality. The authors present the case of a 25-year-old woman with prolactinoma treated with dopamine agonist. In course of such a treatment the patient became pregt. The bromocriptine was gradually withdrawn. In the 14th week of pregcy she was admitted for symptoms suggesting pituitary tumor apoplexy. The treatment with bromocriptine was reinitiated. In the 20th week of pregcy further deterioration of the patient's neurological condition and visual-field abnormalities were observed. The patient was qualified for surgical treatment - selective transsphenoidal adenomectomy. The successful surgery led to improvement of neurological condition. The early postoperative PRL level decreased significantly and hormonal function of the pituitary was preserved. The pregcy ended in 38th week with a caesarean section. Endocrinological evaluation conducted after the uneventful delivery confirmed normal function of the pituitary. Magnetic resoce imaging (MRI) did not reveal tumor re-growth. The patient is kept under constant medical care. In this case study the authors discussed therapeutic management and reviewed literature regarding gestational pituitary-tumor apoplexy with particular emphasis on surgical treatment.

What is the role of mismatched uracil glycosylase (Mug) in DNA repair?

The mismatch-specific uracil DNA glycosylase (MUG) belongs to a homologous family of DNA glycosylases that initiate base-excision repair of G:U/T mismatches. The crystal structure of the Mug repair complex points to a preference of Mug for G:U over G:T mispairs. Nonetheless, Mug does not repair U:G or T:G mismatches in vivo. Mug possesses xanthine DNA glycosylase (XDG) activity in E.coli. The repair activity of Mug is more robust against xanthine than uracil. Furthermore, Mug excises the alkylated base, 3, N(4)-ethenocytosine (epsilonC) from epsilonC:G mismatches, and may be the only enzyme in E.coli that can remove this mutagenic adduct. Thus, the principal role of Mug may be the repair of DNA damages caused by exogenous chemical agents such as chloroacetaldehyde.

G:U mismatches resulting from deamination of cytosine are the most common promutagenic lesions occurring in DNA. Uracil is removed in a base-excision repair pathway by uracil DNA-glycosylase (UDG), which excises uracil from both single- and double-stranded DNA. Recently, a biochemically distinct family of DNA repair enzymes has been identified, which excises both uracil and thymine, but only from mispairs with guanine. Crystal structures of the mismatch-specific uracil DNA-glycosylase (MUG) from E. coli, and of a DNA complex, reveal a remarkable structural and functional homology to UDGs despite low sequence identity. Details of the MUG structure explain its thymine DNA-glycosylase activity and the specificity for G:U/T mispairs, which derives from direct recognition of guanine on the complementary strand. Base-excision of a self-complementary oligonucleotide with central G:T mismatches by the G:T/U-specific mismatch DNA glycosylase (MUG), generates an unusual DNA structure which is remarkably similar in conformation to an interstrand DNA adduct of the anti-tumor drug cis-diamminedichloroplatinum. The abasic sugars generated by excision of the mismatched thymines are extruded from the double-helix, and the 'widowed' deoxyguanosines rotate so that their N7 and O6 groups protrude into the minor groove of the duplex and restack in an interleaved intercalative geometry, generating a kink in the helix axis. The human thymine-DNA glycosylase has a sequence homolog in Escherichia coli that is described to excise uracils from U.G mismatches (Gallinari, P., and Jiricny, J. (1996) Nature 383, 735-738) and is named mismatched uracil glycosylase (Mug). It has also been described to remove 3,N(4)-ethenocytosine (epsilonC) from epsilonC.G mismatches (Saparbaev, M., and Laval, J. (1998) Proc. Natl. Acad. Sci. U. S. A. 95, 8508-8513). We used a mug mutant to clarify the role of this protein in DNA repair and mutation avoidance. We find that inactivation of mug has no effect on C to T or 5-methylcytosine to T mutations in E. coli and that this contrasts with the effect of ung defect on C to T mutations and of vsr defect on 5-methylcytosine to T mutations. Even under conditions where it is overproduced in cells, Mug has little effect on the frequency of C to T mutations. Because uracil-DNA glycosylase (Ung) and Vsr are known to repair U.G and T.G mismatches, respectively, we conclude that Mug does not repair U.G or T.G mismatches in vivo. A defect in mug also has little effect on forward mutations, suggesting that Mug does not play a role in avoiding mutations due to endogenous damage to DNA in growing E. coli. Cell-free extracts from mug(+) ung cells show very little ability to remove uracil from DNA, but can excise epsilonC. The latter activity is missing in extracts from mug cells, suggesting that Mug may be the only enzyme in E. coli that can remove this mutagenic adduct. Thus, the principal role of Mug in E. coli may be to help repair damage to DNA caused by exogenous chemical agents such as chloroacetaldehyde. The Escherichia coli DNA glycosylase Mug excises 3,N(4)-ethenocytosines (epsilon C) and uracils from DNA, but its biological function is obscure. This is because epsilon C is not found in E. coli DNA, and uracil-DNA glycosylase (Ung), a distinct enzyme, is much more efficient at removing uracils from DNA than Mug. We find that Mug is overexpressed as cells enter stationary phase, and it is maintained at a fairly high level in resting cells. This is true of cells grown in rich or minimal media, and the principal regulation of mug is at the level of mRNA. Although the expression of mug is strongly dependent on the stationary-phase sigma factor, sigma(S), when cells are grown in minimal media, it shows only a modest dependence on sigma(S) when cells are grown in rich media. When mug cells are maintained in stationary phase for several days, they acquire many more mutations than their mug(+) counterparts. This is true in ung as well as ung(+) cells, and a majority of new mutations may not be C to T. Our results show that the biological role of Mug parallels its expression in cells. It is expressed poorly in exponentially growing cells and has no apparent role in mutation avoidance in these cells. In contrast, Mug is fairly abundant in stationary-phase cells and has an important anti-mutator role at this stage of cell growth. Thus, Mug joins a very small coterie of DNA repair enzymes whose principal function is to avoid mutations in stationary-phase cells. Glycidaldehyde is an industrial chemical which has been shown to be genotoxic in in vitro experiments and carcinogenic in rodent studies. It is a bifunctional alkylating agent capable of reacting with DNA to form exocyclic hydroxymethyl-substituted ethenobases. In this work, 8-(hydroxymethyl)-3,N4-etheno-2'-deoxycytidine (8-HM-epsilondC), a potential nucleoside derivative of glycidaldehyde, was synthesized using phosphoramidite chemistry and site-specifically incorporated into a defined 25-mer oligodeoxynucleotide. The 8-HM-epsilonC adduct is structurally related to 3,N4-ethenocytosine (epsilonC), a product of reaction with vinyl chloride or through lipid peroxidation. In Escherichia coli, epsilonC has been shown previously to be a primary substrate for the mismatch uracil-DNA glycosylase (Mug). In this study, we report that the same glycosylase also acts on 8-HM-epsilonC in an oligonucleotide duplex. The enzyme binds to the 8-HM-epsilonC-oligonucleotide to a similar extent as the epsilonC-oligonucleotide. The Mug excision activity toward 8-HM-epsilonC is approximately 2.5-fold lower than that toward the epsilonC substrate. Both activities can be stimulated up to approximately 2-fold higher by the addition of E. coli endonuclease IV. These two adducts, when mispaired with normal bases, were all excised from DNA by Mug with similar efficiencies. Structural studies using molecular simulations showed similar adjustment and hydrogen bonding pattern for both 8-HM-epsilonC*G and epsilonC*G pairs in oligomer duplexes. We believe that these findings may have biological and structural implications in defining the role of 8-HM-epsilonC in glycosylase recognition/repair. The promutagenic and genotoxic exocyclic DNA adduct 1,N(2)-ethenoguanine (1,N(2)-epsilonG) is a major product formed in DNA exposed to lipid peroxidation-derived aldehydes in vitro. Here, we report that two structurally unrelated proteins, the Escherichia coli mismatch-specific uracil-DNA glycosylase (MUG) and the human alkylpurine-DNA-N-glycosylase (ANPG), can release 1,N(2)-epsilonG from defined oligonucleotides containing a single modified base. A comparison of the kinetic constants of the reaction indicates that the MUG protein removes the 1,N(2)-epsilonG lesion more efficiently (k(cat)/K(m) = 0.95 x 10(-3) min(-1) nm(-1)) than the ANPG protein (k(cat)/K(m) = 0.1 x 10(-3) min(-1) nm(-1)). Additionally, while the nonconserved, N-terminal 73 amino acids of the ANPG protein are not required for activity on 1,N(6)-ethenoadenine, hypoxanthine, or N-methylpurines, we show that they are essential for 1,N(2)-epsilonG-DNA glycosylase activity. Both the MUG and ANPG proteins preferentially excise 1,N(2)-epsilonG when it is opposite dC; however, unlike MUG, ANPG is unable to excise 1,N(2)-epsilonG when it is opposite dG. Using cell-free extracts from genetically modified E. coli and murine embryonic fibroblasts lacking MUG and mANPG activity, respectively, we show that the incision of the 1,N(2)-epsilonG-containing duplex oligonucleotide has an absolute requirement for MUG or ANPG. Taken together these observations suggest a possible role for these proteins in counteracting the genotoxic effects of 1,N(2)-epsilonG residues in vivo. To maintain genomic integrity, DNA repair enzymes continually remove damaged bases and lesions resulting from endogenous and exogenous processes. These repair enzymes must distinguish damaged bases from normal bases to prevent the inadvertent removal of normal bases, which would promote genomic instability. The mechanisms by which this high level of specificity is accomplished are as yet unresolved. One member of the uracil-DNA glycosylase family of repair enzymes, Escherichia coli mismatch-specific uracil-DNA glycosylase (Mug), is reported to distinguish U:G mispairs from U:A base pairs based upon specific contacts with the mispaired guanine after flipping the target uracil out of the duplex. However, recent studies suggest other mechanisms for base selection, including local duplex stability. In this study, we used the modified base N6-methyladenine to probe the effect of local helix perturbation on Mug recognition of uracil. N6-Methyladenine is found in E. coli as part of both the mismatch repair and restriction-modification systems. In its cis isomer, N6-methyladenine destabilizes hydrogen bonding by interfering with pseudo-Watson-Crick base pairing. It is observed that the selection of uracil by Mug is sequence dependent and that uracil residues in sequences of reduced thermostability are preferentially removed. The replacement of adenine by N6-methyladenine increases the frequency of removal of the uracil residue paired opposite the modified adenine. These results are in accord with suggestions that local helix stability is an important determit of base recognition by some DNA repair enzymes and provide a potential strategy for identifying the sequence location of modified bases in DNA. The oxidation of the thymine methyl group can generate 5-formyluracil (FoU). Template FoU residues are known to miscode, generating base substitution mutations. The repair of the FoU lesion is therefore important in minimizing mutations induced by DNA oxidation. We have studied the repair of FoU in synthetic oligonucleotides when paired with A and G. In E. coli cell extract, the repair of FoU is four orders of magnitude lower than the repair of U and is similar for both FoU:A and FoU:G base pairs. In HeLa nuclear extract, the repair of FoU:A is similarly four orders of magnitude lower than the repair of uracil, although the FoU:G lesion is repaired 10 times more efficiently than FoU:A. The FoU:G lesion is shown to be repaired by E. coli mismatch uracil DNA glycosylase (Mug), thermophile mismatch thymine DNA glycosylase (Tdg), mouse mismatch thymine DNA glycosylase (mTDG) and human methyl-CpG-binding thymine DNA glycosylase (MBD4), whereas the FoU:A lesion is repaired only by Mug and mTDG. The repair of FoU relative to the other pyrimidines examined here in human cell extract differs from the substrate preferences of the known glycosylases, suggesting that additional, and as yet unidentified glycosylases exist in human cells to repair the FoU lesion. Indeed, as observed in HeLa nuclear extract, the repair of mispaired FoU derived from misincorporation of dGMP across from template FoU could promote rather than minimize mutagenesis. The pathways by which this important lesion is repaired in human cells are as yet unexplained, and are likely to be complex. The 3,N(4)-ethenocytosine (epsilon C) residue might have biological role in vivo since it is recognized and efficiently excised in vitro by the E. coli mismatch-specific uracil-DNA glycosylase (MUG) and the human thymine-DNA glycosylase (hTDG). In the present work we have generated mug defective mutant of E. coli by insertion of a kanamycin cassette to assess the role of MUG in vivo. We show that human TDG complements the enzymatic activity of MUG when expressed in a mug mutant. The epsilon C-DNA glycosylase defective strain did not exhibit spontaneous mutator phenotype and did not show unusual sensitivity to any of the following DNA damaging treatments: methylmethanesulfonate, N-methyl-N'-nitro-N-nitrosoguanidine, ultraviolet light, H(2)O(2), paraquat. However, plasmid DNA damaged by 2-chloroacetaldehyde treatment in vitro was inactivated at a greater rate in a mug mutant than in wild-type host, suggesting that MUG is required for the in vivo processing of the ethenobases. In addition, 2-chloroacetaldehyde treatment induces preferentially G.C --> C.G and A.T --> T.A transversions in mug mutant. Comparison of the mutation frequencies induced by the site-specifically incorporated epsilon C residue in E. coli wild-type versus mug indicates that MUG repairs more than 80% of epsilon C residues in vivo. Furthermore, the results show that nucleotide excision repair and recombination are not involved in the processing of epsilon C in E. coli. Based on the mutagenesis data we suggest that epsilon C may be less toxic and less mutagenic than expected. The increased spontaneous mutation rate for G.C --> A.T transition in the ung mug double mutant as compared to the single ung mutant suggest that MUG may be a back-up repair enzyme to the classic uracil-DNA glycosylase. The gene for the mismatch-specific uracil DNA glycosylase (MUG) was identified in the Escherichia coli genome as a sequence homolog of the human thymine DNA glycosylase with activity against mismatched uracil base pairs. Examination of cell extracts led us to detect a previously unknown xanthine DNA glycosylase (XDG) activity in E. coli. DNA glycosylase assays with purified enzymes indicated the novel XDG activity is attributable to MUG. Here, we report a biochemical characterization of xanthine DNA glycosylase activity in MUG. The wild type MUG possesses more robust activity against xanthine than uracil and is active against all xanthine-containing DNA (C/X, T/X, G/X, A/X and single-stranded X). Analysis of potentials of mean force indicates that the double-stranded xanthine base pairs have a relatively narrow energetic difference in base flipping, whereas the tendency for uracil base flipping follows the order of C/U > G/U > T/U > A/U. Site-directed mutagenesis performed on conserved motifs revealed that Asn-140 and Ser-23 are important determits for XDG activity in E. coli MUG. Molecular modeling and molecular dynamics simulations reveal distinct hydrogen-bonding patterns in the active site of E. coli MUG that account for the specificity differences between E. coli MUG and human thymine DNA glycosylase as well as that between the wild type MUG and the Asn-140 and Ser-23 mutants. This study underscores the role of the favorable binding interactions in modulating the specificity of DNA glycosylases. Mismatch uracil DNA glycosylase (Mug) from Escherichia coli is an initiating enzyme in the base-excision repair pathway. As with other DNA glycosylases, the abasic product is potentially more harmful than the initial lesion. Since Mug is known to bind its product tightly, inhibiting enzyme turnover, understanding how Mug binds DNA is of significance when considering how Mug interacts with downstream enzymes in the base-excision repair pathway. We have demonstrated differential binding modes of Mug between its substrate and abasic DNA product using both band shift and fluorescence anisotropy assays. Mug binds its product cooperatively, and a stoichiometric analysis of DNA binding, catalytic activity and salt-dependence indicates that dimer formation is of functional significance in both catalytic activity and product binding. This is the first report of cooperativity in the uracil DNA glycosylase superfamily of enzymes, and forms the basis of product inhibition in Mug. It therefore provides a new perspective on abasic site protection and the findings are discussed in the context of downstream lesion processing and enzyme communication in the base excision repair pathway.

Which are the cardiac effects of thyronamines?

Thyronamines have negative chronotropy, negative inotropy; in particular thyronamines are considered negative inotropic agents

Sulfotransferases (SULTs) catalyze the sulfation of many endogenous compounds that include monoamine neurotransmitters, such as dopamine (DA), and thyroid hormones (iodothyronines). Decarboxylation of iodothyronines results in formation of thyronamines. In the mouse, thyronamines act rapidly in a nongenomic fashion to initiate hypothermia and decrease cardiac output and heart rate. These effects are attenuated after 1-4 h, and metabolism of thyronamines via sulfation may be a mechanism for termination of thyronamine action. We carried out this study to test thyronamine (T0AM), 3-iodothyronamine (T1AM), 3,5-diiodothyronamine (T2AM), and 3,5,3'-triiodothyronamine (T3AM) as substrates for human liver and cDNA-expressed SULT activities. We characterized several biochemical properties of SULTs using the thyronamines that acted as substrates for SULT activities in a human liver high-speed supernatant pool (n=3). T1AM led to the highest SULT activity. Activities with T0AM and T3AM were 10-fold lower, and there was no detectable activity with T2AM. Thyronamines were then tested as substrates with eight cDNA-expressed SULTs (1A1, 1A2, 1A3, 1C2, 1E1, 2A1, 2B1a, and 2B1b). Expressed SULT1A3 had the greatest activity with T0AM, T1AM, and T3AM, whereas SULT1A1 showed similar activity only with T3AM. Expressed SULT1E1 had low activity with each substrate. T1AM, the most active thyronamine pharmacologically, was associated with the greatest SULT activity of the thyronamines tested in the liver pool and in both the expressed SULT1A3 and SULT1E1 preparations. Our results support the conclusion that sulfation contributes to the metabolism of thyronamines in human liver and that SULT activities may regulate the physiological effects of endogenous thyronamines. A class of thyroid hormone metabolites has dramatic physiological effects on metabolism and heart rate by still-unknown mechanisms of action. A recent study has discovered that thyronamines can inhibit neuronal reuptake of neurotransmitters and prevent the intracellular transport of monoamines for release. This discovery presents a third signaling pathway for thyroid hormone, expands the role that thyroid plays in the central nervous system, and suggests mechanisms of action for the effects of thyronamine-derived neuromodulators. Trace amine-associated receptors, a novel class of G-protein coupled receptors which respond to trace amines but not to classical biogenic amines, have been found to be expressed in heart. Therefore, we investigated the cardiac effects of the trace amines p-tyramine, beta-phenylethylamine, octopamine, and tryptamine. Isolated rat hearts were perfused in the presence of trace amines, monitoring the hemodynamic variables. In addition, radioligand binding experiments with [3H]-p-tyramine and [125I]-3-iodothyronamine were performed in rat ventricular tissue. Octopamine, beta-phenylethylamine, and tryptamine produced a dose-dependent negative inotropic effect as shown by reduced cardiac output (IC(50)=109 microM, 159 microM, and 242 microM, respectively). In the same preparation a similar effect was produced by thyronamine and 3-iodothyronamine, with IC(50)=94 microM and 27 microM, respectively. The negative inotropic effect of octopamine was confirmed in a papillary muscle preparation. All trace amines except tryptamine increased the heart rate, but this action could be attributed to their sympathomimetic properties, since it was abolished by propranolol. The negative inotropic effect of trace amines was significantly increased by the tyrosine kinase inhibitor genistein. Specific and saturable binding of [(3)H]-p-tyramine and [125I]-3-iodothyronamine was observed in ventricular tissue. While [3H]-p-tyramine was displaced by 3-iodothyronamine, [(125)I]-3-iodothyronamine was not displaced by p-tyramine. In conclusion, trace amines and thyronamines are negative inotropic agents. Their effect appears to be mediated by a subtype of trace amine-associated receptor which is characterized by the rank of potency: 3-iodothyronamine > thyronamine = octopamine = beta-phenylethylamine, while tryptamine and p-tyramine are significantly less active. Thyroid hormones [predomitly 3, 5, 3 -I- iodothyronine (T3)] regulate cholesterol and lipoprotein metabolism but cardiac effects restrict their use as hypolipidemic drugs. New molecules have been developped which target specifically the thyroid hormone receptor ss, predomit isoform in liver. The first thyroid hormone agonist, called GC1, has selective actions compared to T3. In animals, GC1 reduced serum cholesterol and serum triglycerides, probably by stimulation important steps in reverse cholesterol transport. Other selective thyromimetic, KB- 2115 and KB - 141 have similar effects. Another class of thyroid hormone analogs, the thyronamines have emerged recently but the basic biology of this new class of endogenous thyroid hormone remains to better understood. Therefore, these molecules may be a potentially treatment for obesity and reduction cholesterol, triglycerides and lipoprotein (a). To date the studies in human are preliminary. Tolerance and efficacy of these drugs are still under investigation. 3-Iodothyronamine (T(1)AM) is an endogenous compound derived from thyroid hormone through decarboxylation and deiodination, which interacts with a novel G protein-coupled receptor, known as trace amine-associated receptor 1 (TAAR1). TAAR1 and other receptors of this family are expressed in several tissues, including the heart. Functional effects have been observed after administration of exogenous T(1)AM: in the isolated heart, a negative inotropic and chronotropic action was produced, and the resistance to ischemic injury was increased, possibly as a consequence of an action on intracellular calcium homeostasis. Extracardiac effects include reduction of body temperature, increased lipid versus carbohydrate metabolism, and modulation of insulin secretion. T(1)AM might play an important physiological or pathophysiological role, and this signaling system might allow the development of new therapeutical agents. Thyronamines are naturally occurring, chemical relatives of thyroid hormone. Systemic administration of synthetic 3-iodothyronamine (T(1)AM) and - to a lesser extent - thyronamine (T(0)AM), leads to acute bradycardia, hypothermia, decreased metabolic rate, and hyperglycemia. This profile led us to hypothesize that the central nervous system is among the principal targets of thyronamines. We investigated whether a low dose i.c.v. infusion of synthetic thyronamines recapitulates the changes in glucose metabolism that occur following i.p. thyronamine administration. Plasma glucose, glucoregulatory hormones, and endogenous glucose production (EGP) using stable isotope dilution were monitored in rats before and 120 min after an i.p. (50 mg/kg) or i.c.v. (0.5 mg/kg) bolus infusion of T(1)AM, T(0)AM, or vehicle. To identify the peripheral effects of centrally administered thyronamines, drug-naive rats were also infused intravenously with low dose (0.5 mg/kg) thyronamines. Systemic T(1)AM rapidly increased EGP and plasma glucose, increased plasma glucagon, and corticosterone, but failed to change plasma insulin. Compared with i.p.-administered T(1)AM, a 100-fold lower dose administered centrally induced a more pronounced acute EGP increase and hyperglucagonemia while plasma insulin tended to decrease. Both systemic and central infusions of T(0)AM caused smaller increases in EGP, plasma glucose, and glucagon compared with T(1)AM. Neither T(1)AM nor T(0)AM influenced any of these parameters upon low dose i.v. administration. We conclude that central administration of low-dose thyronamines suffices to induce the acute alterations in glucoregulatory hormones and glucose metabolism following systemic thyronamine infusion. Our data indicate that thyronamines can act centrally to modulate glucose metabolism. 3-iodothyronamine (T1AM) is a novel relative of thyroid hormone, able to interact with specific G protein-coupled receptors, known as trace amine-associated receptors. Significant functional effects are produced by exogenous T1AM, including a negative inotropic and chronotropic effect in cardiac preparations. This work was aimed at estimating endogenous T1AM concentration in different tissues and determining its cardiac metabolism. A novel HPLC tandem mass spectrometry assay was developed, allowing detection of T1AM, thyronamine, 3-iodothyroacetic acid, and thyroacetic acid. T1AM was detected in rat serum, at the concentration of 0.3±0.03 pmol/ml, and in all tested organs (heart, liver, kidney, skeletal muscle, stomach, lung, and brain), at concentrations significantly higher than the serum concentration, ranging from 5.6±1.5 pmol/g in lung to 92.9±28.5 pmol/g in liver. T1AM was also identified for the first time in human blood. In H9c2 cardiomyocytes and isolated perfused rat hearts, significant Na+-dependent uptake of exogenous T1AM was observed, and at the steady state total cellular or tissue T1AM concentration exceeded extracellular concentration by more than 20-fold. In both preparations T1AM underwent oxidative deamination to 3-iodothyroacetic acid. T1AM deamination was inhibited by iproniazid but not pargyline or semicarbazide, suggesting the involvement of both monoamine oxidase and semicarbazide-sensitive amine oxidase. Thyronamine and thyroacetic acid were not detected in heart. Finally, evidence of T1AM production was observed in cardiomyocytes exposed to exogenous thyroid hormone, although the activity of this pathway was very low. Thyronamines (TAMs) are a newly identified class of endogenous signaling compounds. Their structure is identical to that of thyroid hormone and deiodinated thyroid hormone derivatives, except that TAMs do not possess a carboxylate group. Despite some initial publications dating back to the 1950s, TAMs did not develop into an independent area of research until 2004, when they were rediscovered as potential ligands to a class of G protein-coupled receptors called trace-amine associated receptors. Since this discovery, two representatives of TAMs, namely 3-iodothyronamine (3-T(1)AM) and thyronamine (T(0)AM), have been detected in vivo. Intraperitoneal or central injection of 3-T(1)AM or T(0)AM into mice, rats, or Djungarian hamsters caused various prompt effects, such as metabolic depression, hypothermia, negative chronotropy, negative inotropy, hyperglycemia, reduction of the respiratory quotient, ketonuria, and reduction of fat mass. Although their physiological function remains elusive, 3-T(1)AM and T(0)AM have already revealed promising therapeutic potential because they represent the only endogenous compounds inducing hypothermia as a prophylactic or acute treatment of stroke and might thus be expected to cause fewer side effects than synthetic compounds. This review article summarizes the still somewhat scattered data on TAMs obtained both recently and more than 20 yr ago to yield a complete and updated picture of the current state of TAM research. Thyroid hormones are of crucial importance for the functioning of nearly every organ. Remarkably, disturbances of thyroid hormone synthesis and function are among the most common endocrine disorders affecting approximately one third of the working German population. Over the last ten years our understanding of biosynthesis and functioning of these hormones has increased tremendously. This includes the identification of proteins involved in thyroid hormone biosynthesis like Thox2 and Dehal where mutations in these genes are responsible for certain degrees of hypothyroidism. One of the most important findings was the identification of a specific transporter for triiodothyronine (T3), the monocarboxylate transporter 8 (MCT8) responsible for directed transport of T3 into target cells and for export of thyroid hormones out of thyroid epithelial cells. Genetic disturbances of MCT8 in patients result in a biochemical constellation of high T3 levels in combination with low or normal TSH and thyroxine levels leading to a new syndrome of severe X-linked mental retardation. Importantly mice lacking MCT8 presented only with a mild phenotype, indicating that compensatory mechanisms exist in mice. Moreover, it has become clear that not only genomic actions of T3 exist. T3 is also capable to activate adhesion receptors and it signals via activation of PI3K and MAPK pathways. Most recently, thyroid hormone derivatives were identified, the thyronamines which are decarboxylated thyroid hormones initiating physiological actions like lowering body temperature and heart rate, thereby acting in opposite direction to the classical thyroid hormones. So far it is believed that thyronamines function via the activation of a G-protein coupled receptor, TAAR1. The objective of this review is to summarise the recent findings in thyroid hormone synthesis and action and to discuss their implications for diagnosis of thyroid disease and for treatment of patients. Trace amine-associated receptors (TAAR) are rhodopsin-like G-protein-coupled receptors (GPCR). TAAR are involved in modulation of neuronal, cardiac and vascular functions and they are potentially linked with neurological disorders like schizophrenia and Parkinson's disease. Subtype TAAR1, the best characterized TAAR so far, is promiscuous for a wide set of ligands and is activated by trace amines tyramine (TYR), phenylethylamine (PEA), octopamine (OA), but also by thyronamines, dopamine, and psycho-active drugs. Unfortunately, effects of trace amines on signaling of the two homologous β-adrenergic receptors 1 (ADRB1) and 2 (ADRB2) have not been clarified yet in detail. We, therefore, tested TAAR1 agonists TYR, PEA and OA regarding their effects on ADRB1/2 signaling by co-stimulation studies. Surprisingly, trace amines TYR and PEA are partial allosteric antagonists at ADRB1/2, whereas OA is a partial orthosteric ADRB2-antagonist and ADRB1-agonist. To specify molecular reasons for TAAR1 ligand promiscuity and for observed differences in signaling effects on particular aminergic receptors we compared TAAR, tyramine (TAR) octopamine (OAR), ADRB1/2 and dopamine receptors at the structural level. We found especially for TAAR1 that the remarkable ligand promiscuity is likely based on high amino acid similarity in the ligand-binding region compared with further aminergic receptors. On the other hand few TAAR specific properties in the ligand-binding site might determine differences in ligand-induced effects compared to ADRB1/2. Taken together, this study points to molecular details of TAAR1-ligand promiscuity and identified specific trace amines as allosteric or orthosteric ligands of particular β-adrenergic receptor subtypes.

Matuzumab has been tested for treatment of which cancers?

Matuzumab has been tested for treatment of non-small cell lung, gastric, esophageal, colorectal, primary peritoneal, pancreatic, ovarian and cervical cancers.

Merck KGaA is developing matuzumab, a fully humanized epidermal growth factor receptor (EGFR)-specific monoclonal antibody, as a potential treatment for EGFR-bearing tumors. Matuzumab is currently undergoing phase II clinical trials for gastric, cervical, pancreatic and ovarian cancers. The epidermal growth factor receptor (EGFR) is overexpressed in as many as 77% of colorectal cancer (CRC) cases. The EGFR is known to be involved in carcinogenetic processes such as cell proliferation, apoptosis, angiogenesis, cell motility, and metastasis. Preclinical and clinical studies have shown that targeting EGFR is a valid strategy for anticancer therapy. Currently, 2 classes of anti-EGFR agents are in phase II/III clinical development: monoclonal antibodies and tyrosine kinase (TK) inhibitors. The most established monoclonal antibody is cetuximab, the only EGFR inhibitor that is currently approved for use in patients with metastatic CRC. Several clinical studies of cetuximab, as a single agent or in combination with irinotecan, have shown promising efficacy in patients with metastatic CRC. Two other monoclonal antibodies, matuzumab (EMD 72000) and panitumumab (ABG-EGF), also have shown activity against EGFR-expressing CRC but are still in the early stage of clinical development. The activity of the EGFR TK inhibitors erlotinib and gefitinib have already been investigated in clinical phase III trials in patients with non-small-lung cancer, suggesting that sequential rather than concurrent erlotinib/gefitinib-based treatment provides a benefit in clinical outcome. The EGFR-targeting agents are reasonably well tolerated and have limited overlapping toxicities in combination with other cytotoxic drugs. The most common side effect of anti-EGFR treatment is an acneiform skin rash, which is associated with the clinical outcome of treatment with monoclonal antibodies and TK inhibitors. Future clinical studies are needed to establish these EGFR-targeting agents in anticancer treatment to investigate efficacy of therapies combining EGFR-targeted agents with other targeting agents and to describe additional markers determining the clinical outcome of anti-EGFR therapy. The epidermal growth factor receptor (EGFR) is overexpressed in the majority of colorectal cancers. It is the target for a class of agents at the forefront of development for the treatment of colorectal cancer, ie, the anti-EGFR monoclonal antibodies, which include cetuximab, panitumumab, and matuzumab. At present, cetuximab is the furthest along in terms of established efficacy in the treatment of metastatic or inoperable disease and is licensed for the treatment of patients with irinotecan-refractory colorectal cancer. This article reviews the recent evidence supporting the combination of these anti-EGFR agents with the cytotoxic chemotherapeutic agent irinotecan. Nowadays, targeting epidermal growth factor-receptor (EGFR) represents an additional therapeutic line for patients with metastatic colorectal cancer (MCRC). Cetuximab, the first available anti-EGFR monoclonal antibody, is approved, combined to irinotecan, in EGFR-positive MCRC after progression while under an irinotecan-based chemotherapy. Other anti-EGFR monoclonal antibodies (panitunumab, matuzumab) are currently evaluated. Preliminary data seem to indicate similar efficacy and toxicity profile to that of cetuximab. Orally available EGFR tyrosine kinase inhibitors (gefitinib, erlotinib, EKB 569) have also been evaluated in patients with MCRC. Preliminary data in terms of clinical activity are not favouring their combination to conventional chemotherapy. Furthermore, they seem to increase the rate of severe haematological and digestive toxicities, especially in patients previously exposed to chemotherapy. At this point of the clinical development of these all EGFR inhibitors (monoclonal antibodies or tyrosine kinase inhibitors) in MCRC, informative data from randomized studies are urgently needed. BACKGROUND: Epidermal growth factor receptor (EGFR) is overexpressed in 80%-90% of non-small-cell lung cancer (NSCLC). Matuzumab, a humanized immunoglobulin G(1) (IgG(1)) anti-EGFR monoclonal antibody, blocks activation of EGFR. Paclitaxel and EGFR inhibitors have additive antitumour effects in vitro. This phase I study assessed the tolerability, pharmacokinetics and efficacy of the combination of matuzumab and paclitaxel in patients with advanced NSCLC. MATERIALS AND METHODS: Eighteen chemotherapy-naïve (n = 9) or pretreated (n = 9) patients with stage IIIB or IV EGFR-positive NSCLC received weekly doses of matuzumab (100, 200, 400 or 800 mg) followed by paclitaxel 175 mg/m(2) every 3 weeks. Toxicity was evaluated weekly and pharmacokinetics were measured during cycles 1 and 2. RESULTS: The maximum planned matuzumab dose of 800 mg was achieved without reaching the maximum tolerated dose. Grade 4 neutropenia occurred in one of three patients at 800 mg but resolved within 1 week; five additional patients treated with 800 mg had no dose-limiting toxicity (DLT). Grade 1/2 acneiform skin rash in 14 patients was the most frequent matuzumab-related side-effect. There were no higher-grade adverse events. Grade 2 toxicities included pruritus (n = 2), bronchospasm (n = 1), fissures (n = 1), abdominal pain (n = 1) and hot flushes (n = 1). Paclitaxel was discontinued in four patients due to allergic reactions. Coadministration of paclitaxel did not alter matuzumab pharmacokinetics. Responses occurred in four of 18 patients and included one complete response. CONCLUSIONS: Matuzumab doses up to 800 mg weekly with paclitaxel 175 mg/m(2) every 3 weeks are well tolerated, with no apparent drug interactions and with evidence of antitumor activity. The epidermal growth factor receptor (EGFR) inhibitors erlotinib, gefitinib, and cetuximab have undergone extensive clinical testing and have established clinical activity in non-small cell lung cancer and other types of solid tumors. A number of newer inhibitors are currently in clinical development with different spectra of activity or mechanisms of receptor inhibition. These include monoclonal antibodies, such as panitumumab and matuzumab; dual inhibitors of EGFR and vascular endothelial growth factor receptor, such as ZD6474 and AEE788; inhibitors of multiple EGFR family members, such as lapatinib; and irreversible inhibitors, such as canertinib and HKI272. Preclinical studies suggest that several of these agents may have activity in tumors refractory to erlotinib or gefitinib. Among these agents, ZD6474 has undergone the most extensive clinical testing. The antitumor activity of ZD6474 in these two randomized phase II clinical trials in patients with non-small cell lung cancer was felt to be sufficiently promising to warrant phase III clinical testing. Several of the other EGFR inhibitors are also undergoing advanced clinical testing, either alone or in combination with other agents. EGFR has now been validated as a clinically relevant target, and several different types of agents inhibiting this receptor are currently in development. Future research will be needed to elucidate the role of these agents in patients with EGFR inhibitor-naive and EGFR inhibitor-refractory disease, to define the molecular characteristics that predict response, and to determine whether these drugs should be used in combination with other targeted agents or chemotherapy. OBJECTIVE: The primary objective of this study was to determine the rate of response to matuzumab in patients with recurrent, EGFR-positive ovarian, or primary peritoneal cancer. Secondary end points included safety and tolerability, time to tumor progression, duration of response, and overall survival. METHODS: A multi-institutional single arm phase II trial. RESULTS: Of 75 women screened for the study, 37 were enrolled and treated. Median age of the treated patient population was 58 years, and most patients had more than four prior lines of chemotherapy. Therapy was well tolerated, the most common toxicities being a constellation of skin toxicities, including rash, acne, dry skin, and paronychia, as well as headache, fatigue, and diarrhea. Serious adverse events were very rare but included a single episode of pancreatitis that may have been drug related. All patients completed therapy, receiving 1 to 30 infusions of matuzumab. There were no formal responses (RR=0%, 95% CI: 0-9.5%), although 7 patients (21%) were on therapy for more than 3 months with stable disease. CONCLUSIONS: Matuzumab at the dose and schedule selected is well tolerated. In this population of very heavily pretreated patients with epithelial ovarian and primary peritoneal maligcies, there was no evidence of significant clinical activity when matuzumab was administered as monotherapy. Antibodies targeting epidermal growth factor receptor (EGFR) have proven to be effective in patients with non-small cell lung cancer (NSCLC) that express EGFR. We recently published a phase I study of weekly matuzumab plus paclitaxel. This therapy was well tolerated and showed clinical responses in the majority of patients. Although matuzumab displays potent antitumor activity in some patients, not all patients respond well to treatment. Whether dysregulation of EGFR-mediated pathways precludes or sensitizes cells to paclitaxel is unknown. We sought to determine molecular predictive factors for therapy response in a phase I/II study patient cohort treated with matuzumab+/-paclitaxel. Twenty-three cases [including one complete response (CR), three partial responses (PR), 10 stable diseases (SD)] were screened using immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), PCR/sequencing and denaturing wave high performance liquid chromatography (D-HPLC) for expression, amplification, and mutation status of EGFR and downstream signaling pathways. All patients with PR or CR displayed an either high overall or single-cell EGFR expression in the majority of cells. In addition, all of the moderate responders, who achieved SD after at least two cycles of therapy, showed diffuse EGFR expression rates and/or strong single-cell EGFR expression. In contrast, 44% of the nonresponders showed low overall or single-cell EGFR expression levels. No low-expressing EGFR cases were present within the responder group. In addition, among patients with a gain-of-function mutation in KRAS primary therapy failure and/or short responses to therapy were observed. Our data suggest that EGFR expression and KRAS mutation status is predictive for clinical response to matuzumab +/- paclitaxel in patients with advanced NSCLC. Bronchial and head and neck (HN) cancers share similarities especially regarding the HER pathway. Therapeutic progresses targeting the HER pathway are based on monoclonal antibodies, especially cetuximab, and tyrosine kinase (TK) inhibitors, targeting HER only, as gefitinib and erlotinib, or HER and other receptor(s), as VEGFR for the ZD6474. The results obtained already led to the registration of cetuximab (combined with radiotherapy) for management of locally advanced HN cancers, and the registration of erlotinib (and gefitinib in some countries) for management of non-small-cell lung cancer (NSCLC) in the second or third line setting. Therefore, these first successes led to the development of several drugs including monoclonal antibodies (trastuzumab, panitumumab, matuzumab), TK inhibitors targeting one receptor as well as TK pan-inhibitors (lapatinib, HKI 272, PKI 166, EKB-569, AEE-788), currently assessed through clinical trials worldwide. In the same time, progresses regarding the HER pathway also focused on a better selection of patients who clearly beneficiate from these drugs (EGFR gene mutations, EGFR gene amplification by FISH) allowing the first steps in tailoring anticancer treatments in lung cancer. In conclusion, therapeutic progresses targeting the HER pathway have improve management of HN and NSCLC patients and rise hopes for the future. Non-small cell lung cancer (NSCLC) accounts for about 85% of all new diagnoses of lung cancer. Unfortunately, few NSCLC patients are suitable for radical treatment for curative intent. Because most patients with NSCLC have advanced disease at diagnosis, chemotherapy represents the standard of care, although, to date, a plateau has been reached with this approach. Improvements in the knowledge of tumor biology and mechanisms of oncogenesis have identified the epidermal growth factor receptor (EGFR), a member of the ErbB family, as a molecular target for NSCLC treatment. EGFR is commonly overexpressed in NSCLC and has been associated with impaired prognosis; therefore, its inhibition may lead, through the suppression of tumor proliferation, to improvement in clinical outcomes. Strategies to block EGFR include tyrosine kinase inhibitors, monoclonal antibodies, ligand-linked toxins, and antisense approaches. This article focuses on the treatment of NSCLC with the anti-EGFR monoclonal antibodies, including cetuximab, for which the largest amount of data in the literature exists. Recently, a phase III randomized trial performed in advanced NSCLC patients yielded a statistically significant survival advantage for patients treated with cetuximab plus chemotherapy versus chemotherapy alone. Other anti-EGFR monoclonal antibodies, such as panitumumab, matuzumab, nimotuzumab, and ch806, are in different stages of development for the treatment of advanced NSCLC. OBJECTIVES: A developed population pharmacokinetic model of the humanized monoclonal antibody (mAb) matuzumab was evaluated by external evaluation. Based on the estimates of the final model, simulations of different dosing regimens and the covariate effect were performed. METHODS: The development dataset included 90 patients, and the evaluation dataset included 81 patients; the two sets of patients were from three different studies. In all studies, the patients had different types of advanced carcinoma - mainly colon, rectal and pancreatic cancer. They received matuzumab as multiple 1-hour intravenous infusions in a wide range of dosing regimens (development dataset: from 400 mg every 3 weeks to 2000 mg in the first week followed by 1600 mg weekly; evaluation dataset: from 100 mg weekly to 800 mg weekly). In addition to 1256 serum mAb concentrations for model development, there were 1124 concentrations available for model evaluation. Serum concentration-time data were simultaneously fitted using NONMEM software. The developed two-compartment model - with the parameters central volume of distribution (V(1)) and peripheral volume of distribution (V(2)), intercompartmental clearance and linear clearance (CLL), an additional nonlinear elimination pathway (Michaelis-Menten constant: the concentration with the half-maximal elimination rate and V(max): the maximum elimination rate) and covariate relations - was evaluated by an external dataset. Different simulation scenarios were performed to demonstrate the impact of the incorporated covariate effect and the influence of different dosing regimens and dosing strategies on the concentration-time profiles. RESULTS: The developed model included the covariate fat-free mass (FFM) on V(1) and on CLL. The evaluation did not support the covariate FFM on V(1) and, after deletion of this covariate, the model parameters of the refined model were estimated. The model showed good precision for all parameters: the relative standard errors (RSEs) were <42% for the development dataset and < or = 51% for the evaluation dataset (excluding the higher RSEs for the correlation between V(2) and V(max) and the interindividual variability on V(2) for the evaluation dataset). The model showed good robustness for the ability to estimate highly precise parameters for the combined dataset of 171 patients (RSE <29%). Simulations revealed that variability in concentration-time profiles for minimum and maximum steady-state concentrations was reduced to a marginal extent by a proposed dose adaptation. CONCLUSION: The population pharmacokinetic model for matuzumab was improved by evaluation with an external dataset. The new model obtained precise parameter estimates and demonstrated robustness. After correlation with efficacy data simulation results in particular could serve as a tool to guide dose selection for this 'targeted' cancer therapy. BACKGROUND: Clinical data showed promising antitumour activity with feasible tolerability for matuzumab plus epirubicin, cisplatin and capecitabine (ECX) chemotherapy in untreated advanced oesophago-gastric (OG) cancer. The aim was to evaluate the efficacy of matuzumab plus ECX versus ECX alone. PATIENTS AND METHODS: In this multicentre, randomised open-label phase II study, 72 patients with metastatic OG cancer were randomly assigned to either 800 mg matuzumab weekly plus epirubicin 50 mg/m², cisplatin 60 mg/m² on day 1 and capecitabine 1250 mg/m² daily in a 21-day cycle (ECX) or the same ECX regimen alone. The primary end point was objective response. Secondary end points included progression-free survival (PFS), overall survival (OS), quality of life, safety and tolerability. RESULTS: Following random assignment, 35 patients (median age 59 years) received ECX/matuzumab and 36 patients (median age 64 years) ECX. The addition of matuzumab to ECX did not improve objective response: 31% for ECX/matuzumab [95% confidence interval (CI) 17-49] compared with 58% for the ECX arm (95% CI 41-74) P = 0.994 (one sided). There was no significant difference in median PFS: 4.8 months (95% CI 2.9-8.1) for ECX/matuzumab versus 7.1 months (95% CI 4.4-8.5) for ECX, or in median OS: 9.4 months (95% CI 7.5-16.2), compared with 12.2 months (95% CI 9.8-13.8 months). Grade 3/4 treatment-related toxicity was observed in 27 and 25 patients in the ECX/matuzumab and ECX groups, respectively. CONCLUSION: Matuzumab 800 mg weekly combined with ECX chemotherapy does not increase response or survival for patients with advanced OG cancer. Therefore, ECX/matuzumab should not be examined further in phase III trials. INTRODUCTION: This randomized phase II study investigated pemetrexed in combination with the epidermal growth factor receptor (EGFR)-targeting monoclonal antibody matuzumab compared with pemetrexed alone as second-line therapy for patients with advanced non-small cell lung cancer. METHODS: Patients received pemetrexed 500 mg/m every 3 weeks either alone (n = 50) or in combination with matuzumab at either 800 mg weekly (n = 51) or 1600 mg every 3 weeks (n = 47). The primary end point was objective response, as assessed by an independent review committee. RESULTS: Tumor EGFR expression was detected in 87% of randomized patients. The objective response rate for the pooled matuzumab-treated arms was 11% compared with 5% for pemetrexed alone (p = 0.332). Apart from one patient in the pemetrexed alone group, all responses occurred in patients whose tumors expressed EGFR. The objective response rate for patients receiving weekly matuzumab was 16% compared with 2% for those receiving matuzumab every 3 weeks. There was also a trend for improved overall survival in patients receiving matuzumab weekly versus every 3 weeks (12.4 months versus 5.9 months, respectively, versus 7.9 months for pemetrexed alone). The combination of pemetrexed and matuzumab demonstrated an acceptable safety profile, with the most common grade 3/4 adverse event being neutropenia. CONCLUSION: Although the analysis on the pooled matuzumab-treated arms did not demonstrate a statistically significant improvement in objective response for the addition of matuzumab to pemetrexed compared with pemetrexed alone, the trends for improvement in objective response and overall survival for pemetrexed plus weekly matuzumab compared with pemetrexed alone warrant confirmation in additional clinical trials. Blockade of the epidermal growth factor receptor (EGFR) by monoclonal antibodies is a strategy to improve outcome in patients with non-small cell lung cancer. Cetuximab, a chimeric anti-EGFR monoclonal antibody, has been studied in combination with different chemotherapy protocols in both phase II and phase III trials in patients with advanced NSCLC. In the phase III FLEX trial, cetuximab added to cisplatin/vinorelbine resulted in an absolute overall survival benefit of 1.2 months compared to the same chemotherapy alone in patients with advanced EGFR-expressing NSCLC. In the second phase III trial, cetuximab added to carboplatin plus paclitaxed failed to improve progression-free survival but suggested a survival benefit similar to that seen in the FLEX trial. However, the benefit in survival reached statistical significance only in the FLEX trial. A meta-analysis that included patients from four randomized trials confirmed the efficacy of cetuximab when added to chemotherapy. Thus addition of cetuximab to platinum-based chemotherapy represents a new treatment option for patients with advanced NSCLC. Matuzumab and panitumumab have also been evaluated in phase II trials. Necitumumab is currently evaluated in combination with chemotherapy in two randomized phase III trials. BACKGROUND: To evaluate the safety and tolerability of two different weekly doses of the fully humanized epidermal growth factor receptor (EGFR)-targeting monoclonal antibody matuzumab combined with high-dose 5-fluorouracil, leucovorin and cisplatin (PLF) in the first-line treatment of patients with EGFR-positive advanced gastric and esophagogastric adenocarcinomas. METHODS: Patients were treated in two matuzumab dose groups with the first cohort of patients receiving 400 mg matuzumab in combination with PLF. Based on the safety observations the next cohort of patients received 800 mg matuzumab. The study was conducted in two parts, with phase A, designed to assess the safety and tolerability of the combination, and phase B designed to be a treatment continuation for those patients benefiting from treatment. Treatment cycles were 7 weeks each. Each patient received the dose of matuzumab they were assigned to at study entry for the duration of the study. RESULTS: Fifteen EGFR-positive patients were enrolled into the two matuzumab dose groups; 400 mg dose n=7; 800 mg dose n=8. All patients experienced at least one adverse event (AE). No patient experienced any serious AE which was considered to be related to matuzumab. Two grade 3 AEs possibly related to matuzumab occurred in 2 different patients (13.3 %), both in the 800 mg dose group. No dose-limiting toxicity (DLT) was observed in the 400 mg group. The maximum tolerated dose of matuzumab was not reached. The best confirmed overall response rate was 26.7 %. CONCLUSION: Matuzumab, in combination with PLF, demonstrated an acceptable safety profile with modest anti-tumor activity. Gastric cancer (GC) is currently the second leading cause of cancer death worldwide; unfortunately, most patients will present with locally advanced or metastatic disease. Despite recent progress in diagnosis, surgery, chemotherapy, and radiotherapy, prognosis remains poor. A better understanding of GC biology and signaling pathways is expected to improve GC therapy, and the integration of targeted therapies has recently become possible and appears to be promising. This article focuses on anti-Her-2 therapy, specifically trastuzumab, as well as other epidermal growth factor receptor antagonists such as cetuximab, panitumub, matuzumab, nimotzumab, gefitinib, and erlotinib. Additionally, drugs that target angiogenesis pathways are also under investigation, particulary bevacizumab, ramucirumab, sorafenib, sunitinib, and cediranib. Other targeted agents in preclinical or early clinical development include mTOR inhibitors, anti c-MET, polo-like kinase 1 inhibitors, anti-insulin-like growth factor, anti-heat shock proteins, and small molecules targeting Hedgehog signaling. Matuzumab is a humanized IgG1 EGFR monoclonal antibody. This phase I study investigated the tolerability, safety and pharmacokinetics (PK) of matuzumab in combination with paclitaxel in patients with EGFR-expressing advanced non-small cell lung cancer (NSCLC). Six dose levels/schedules of matuzumab were explored in combination with paclitaxel. Dose was escalated from 100 mg to 1,600 mg on a modified Fibonacci scheme according to the incidence of dose-limiting toxicity (DLT) over the first two cycles. DLT was assessed in patients who completed the first two treatment cycles or who stopped treatment because of a DLT during those cycles. Patients with non-progressive disease could then continue to receive study treatment for up to 6 months. The safety population comprised 44 patients, with DLT evaluable in 33. The maximum tolerated dose was not reached, with only one DLT reported at the 1,600 mg 3-weekly dose level. The most frequent grade 3/4 adverse events across all cycles were dyspnea (23 %) and neutropenia (11 %). Matuzumab exhibited non-linear PK, with accumulation after escalation and repeated dosing. Tumor growth control was seen in 15/44 (34 %) patients, including 5/9 (56 %) at the 800 mg weekly dose level. Matuzumab combined with paclitaxel was generally well tolerated in patients with advanced NSCLC. There was some evidence of anticancer activity in relation to the matuzumab 800 mg weekly dose.

Which are the synonyms of prostate-specific antigen?

Prostate-specific antigen (PSA) is a 33 kDa single chain glycoprotein belonging to the kallikrein family of serine proteases which is produced by epithelial cells of both normal and malignant prostate tissue. PSA is an important marker for the diagnosis of prostate cancer. PSA is also known as human kallikrein-related peptidase 3 (hK3).

Human kallikrein-related peptidase 3 (hK3), also known as prostate-specific antigen (PSA), is a 33 kDa single chain glycoprotein belonging to the kallikrein family of serine proteases. With chymotrypsin-like enzymatic activity, hK3 is directly and indirectly involved in a number of diverse biological functions including male fertility, the regulation of cell proliferation, and the inhibition of angiogenesis. The gene encoding hK3, hKLK3, is located on chromosome 19 and its expression has been shown to be regulated by steroid hormones through androgen receptor-mediated transcription. hK3 was once thought to be exclusively expressed and secreted by prostatic epithelial cells, hence the initial name of prostate-specific antigen, but has since been isolated in several nonprostatic tissues and ongoing characterization of alternative splicing variants has found at least 13 distinct mRNA transcripts. The detection of hK3 in cerebrospinal fluid prompted the hypothesis that hK3 may be produced in the brain. To test this notion, in this study we used RT-PCR amplification of brain tissue total RNA and examined hK3 protein by immunohistochemical, and immunoblot analysis. RT-PCR revealed several hK3 mRNA transcripts in the brain. Confirming these findings, both immunohistochemical staining and western immunoblotting showed evidence for hK3 protein in neuronal cells. Taken together, our findings support the expression of hK3 in neuronal cells reinforcing the concept of hK3 as a ubiquitous protein with more multifarious biological activity than previously believed. Ongoing research seeks to elucidate the functional significance of hK3 in brain cells.

What is the lipid droplet used for in the cell?

Lipid droplets (LDs) are ubiquitous and physiologically active organelles regulating storage and mobilization of lipids in response to metabolic demands.

Several human worldwide diseases like obesity, type 2 diabetes, hepatic steatosis, atherosclerosis and other metabolic pathologies are related to the excessive accumulation of lipids in cells. Lipids accumulate in spherical cellular inclusions called lipid droplets (LDs) whose sizes range from fraction to one hundred of micrometers in adipocytes. It has been suggested that LDs can grow in size due to a fusion process by which a larger LD is obtained with spherical shape and volume equal to the sum of the progenitors' ones. In this study, the size distribution of two populations of LDs was analyzed in immature and mature (5-days differentiated) 3T3-L1 adipocytes (first and second populations, respectively) after Oil Red O staining. A Monte Carlo simulation of interaction between LDs has been developed in order to quantify the size distribution and the number of fusion events needed to obtain the distribution of the second population size starting from the first one. Four models are presented here based on different kinds of interaction: a surface weighted interaction (R2 Model), a volume weighted interaction (R3 Model), a random interaction (Random model) and an interaction related to the place where the LDs are born (Nearest Model). The last two models mimic quite well the behavior found in the experimental data. This work represents a first step in developing numerical simulations of the LDs growth process. Due to the complex phenomena involving LDs (absorption, growth through additional neutral lipid deposition in existing droplets, de novo formation and catabolism) the study focuses on the fusion process. The results suggest that, to obtain the observed size distribution, a number of fusion events comparable with the number of LDs themselves is needed. Moreover the MC approach results a powerful tool for investigating the LDs growth process. Lipid droplets (LDs) are ubiquitous and physiologically active organelles regulating storage and mobilization of lipids in response to metabolic demands. Among the constituent LD neutral lipids, such as triacylglycerols, cholesterol esters, and free fatty acids, oxidizable polyunsaturated molecular species may be quite abundant, yet the structural and functional roles of their oxidation products have not been studied. Our previous work documented the presence of these peroxidized species in LDs. Assuming that hydrophilic oxygen-containing functionalities may markedly change the hydrophobic/hydrophilic molecular balance, here we utilized computational modeling to test the hypothesis that lipid peroxidation causes redistribution of lipids between the highly hydrophobic core and the polar surface (phospho)lipid monolayer-the area enriched with integrated enzymatic machinery. Using quantitative liquid chromatography/mass spectrometry, we characterized molecular speciation of oxTAGs in LDs of dendritic cells in cancer and hypoxic trophoblasts cells as two cellular models associated with dyslipidemia. Among the many types of oxidized lipids identified, we found that oxidatively truncated forms and hydroxyl derivatives of TAGs were the prevailing oxidized lipid species in LDs in both cell types. Using coarse-grained molecular dynamics (CG-MD) simulations we established that lipid oxidation changed their partitioning whereby oxidized lipids migrated into the outer monolayer of the LD, where they can affect essential metabolic pathways and undergo conversions, possibly leading to the formation of oxygenated lipid mediators. Lipid droplets are found in all cell types. Normally present at low levels in the brain, they accumulate in tumours and are associated with neurodegenerative diseases. However, little is known about the mechanisms controlling their homeostasis in the brain. We found that GRAF1a, the longest GRAF1 isoform (GRAF1 is also known as ARHGAP26), was enriched in the brains of neonates. Endogenous GRAF1a was found on lipid droplets in oleic-acid-fed primary glial cells. Exclusive localization required a GRAF1a-specific hydrophobic segment and two membrane-binding regions, a BAR and a PH domain. Overexpression of GRAF1a promoted lipid droplet clustering, inhibited droplet mobility and severely perturbed lipolysis following the chase of cells overloaded with fatty acids. Under these conditions, GRAF1a concentrated at the interface between lipid droplets. Although GRAF1-knockout mice did not show any gross abnormal phenotype, the total lipid droplet volume that accumulated in GRAF1(-/-) primary glia upon incubation with fatty acids was reduced compared to GRAF1(+/+) cells. These results provide additional insights into the mechanisms contributing to lipid droplet growth in non-adipocyte cells, and suggest that proteins with membrane sculpting BAR domains play a role in droplet homeostasis. Eukaryotic cells store excess fatty acids as neutral lipids, predomitly triacylglycerols and sterol esters, in organelles termed lipid droplets (LDs) that bulge out from the endoplasmic reticulum. LDs are highly dynamic and contribute to diverse cellular functions. The catabolism of the storage lipids within LDs is channeled to multiple metabolic pathways, providing molecules for energy production, membrane building blocks, and lipid signaling. LDs have been implicated in a number of protein degradation and pathogen infection processes. LDs may be linked to prevalent human metabolic diseases and have marked potential for biofuel production. The knowledge accumulated on LDs in recent years provides a foundation for diverse, and even unexpected, future research. This review focuses on recent advances in LD research, emphasizing the diverse physiological roles of LDs in the model system of budding yeast. Lipid droplets (LD) are spherical cellular inclusion devoted to lipids storage. It is well known that excessive accumulation of lipids leads to several human worldwide diseases like obesity, type 2 diabetes, hepatic steatosis and atherosclerosis. LDs' size range from fraction to one hundred of micrometers in adipocytes and is related to the lipid content, but their growth is still a puzzling question. It has been suggested that LDs can grow in size due to the fusion process by which a larger LD is obtained by the merging of two smaller LDs, but these events seems to be rare and difficult to be observed. Many other processes are thought to be involved in the number and growth of LDs, like the de novo formation and the growth through additional neutral lipid deposition in pre-existing droplets. Moreover the number and size of LDs are influenced by the catabolism and the absorption or interaction with other organelles. The comprehension of these processes could help in the confinement of the pathologies related to lipid accumulation. In this study the LDs' size distribution, number and the total volume of immature (n=12), mature (n=12, 10-days differentiated) and lipolytic (n=12) 3T3-L1 adipocytes were considered. More than 11,000 LDs were measured in the 36 cells after Oil Red O staining. In a previous work Monte Carlo simulations were used to mimic the fusion process alone between LDs. We found that, considering the fusion as the only process acting on the LDs, the size distribution in mature adipocytes can be obtained with numerical simulation starting from the size distribution in immature cells provided a very high rate of fusion events. In this paper Monte Carlo simulations were developed to mimic the interaction between LDs taking into account many other processes in addition to fusion (de novo formation and the growth through additional neutral lipid deposition in pre-existing droplets) in order to reproduce the LDs growth and we also simulated the catabolism (fission and the decrease through neutral lipid exit from pre-existing droplets) to reproduce their size reduction observed in lipolytic conditions. The results suggest that each single process, considered alone, can not be considered the only responsible for the size variation observed, but more than one of them, playing together, can quite well reproduce the experimental data.

What is the function of circular RNA?

Circular RNAs (circRNAs) are a novel type of RNA that, unlike linear RNAs, form a covalently closed continuous loop and are highly represented in the eukaryotic transcriptome. The biogenesis of circular RNA is an integral, conserved, and regulated feature of the gene expression program. Circular RNAs play a crucial role in fine tuning the level of miRNA mediated regulation of gene expression by sequestering the miRNAs. Recent research has revealed that circRNAs can function as microRNA (miRNA) sponges, regulators of splicing and transcription, and modifiers of parental gene expression.

We previously identified novel human ets-1 transcripts in which the normal order of exons is inverted, and demonstrated that although the order of exons is different than in the genomic DNA, splicing of these exons out of order occurs in pairs using genuine splice sites (1). Here we determine the structure of these novel transcripts, showing that they correspond to circular RNA molecules containing only exons in genomic order. These transcripts are stable molecules, localized in the cytoplasmic component of the cells. To our knowledge, this is the first case of circular transcripts being processed from nuclear pre-mRNA in eukaryotes. This new type of transcript might represent a novel aspect of gene expression and hold some interesting clues about the splicing mechanism. Thousands of loci in the human and mouse genomes give rise to circular RNA transcripts; at many of these loci, the predomit RNA isoform is a circle. Using an improved computational approach for circular RNA identification, we found widespread circular RNA expression in Drosophila melanogaster and estimate that in humans, circular RNA may account for 1% as many molecules as poly(A) RNA. Analysis of data from the ENCODE consortium revealed that the repertoire of genes expressing circular RNA, the ratio of circular to linear transcripts for each gene, and even the pattern of splice isoforms of circular RNAs from each gene were cell-type specific. These results suggest that biogenesis of circular RNA is an integral, conserved, and regulated feature of the gene expression program. Circular RNAs are new players in regulation of post transcriptional gene expression. Animal genomes express many circular RNAs from diverse genomic locations. A recent study has validated a fairly large number of circular RNAs in human, mouse, and nematode. Circular RNAs play a crucial role in fine tuning the level of miRNA mediated regulation of gene expression by sequestering the miRNAs. Their interaction with disease associated miRNAs indicates that circular RNAs are important for disease regulation. In this paper we studied the potential association of circular RNAs (circRNA) with human diseases in two different ways. Firstly, the interactions of circRNAs with disease associated miRNAs were identified, following which the likelihood of a circRNA being associated with a disease was calculated. For the miRNAs associated with individual diseases, we constructed a network of predicted interactions between the miRNAs and protein coding, long non-coding and circular RNA genes. We carried out gene ontology (GO) enrichment analysis on the set of protein coding genes in the miRNA- circRNA interactome of individual diseases to check the enrichment of genes associated with particular biological processes. Secondly, disease associated SNPs were mapped on circRNA loci, and Argonaute (Ago) interaction sites on circular RNAs were identified. We compiled a database of disease-circRNA association in Circ2Traits (http://gyanxet-beta.com/circdb/), the first comprehensive knowledgebase of potential association of circular RNAs with diseases in human.

Can NXY-059 be used for treatment of acute ischemic stroke patients?

No. 2,4-disulfonylphenyl PBN derivative, called NXY-059 in the stroke studies, was shown to be safe in humans and was taken all the way through clinical phase 3 trials and then was deemed to be ineffective.

NXY 059 [CPI 22, NXY 059G], a nitrone with free radical trapping properties, has potential in the treatment of ischaemic stroke.This profile has been selected from R&D Insight, a pharmaceutical intelligence database produced by Adis International Ltd. NXY 059 is based on Centaur Pharmaceuticals' proprietary Nitrone-Related Therapeutics (NRT) technology. A generic form of NXY 059, NXY 059G, has been synthesised. On 12 December 2002, Centaur Pharmaceuticals was acquired by, and integrated into, Renovis. AstraZeneca has exclusive worldwide rights to NXY 059, under a licence from Centaur Pharmaceuticals; the licensing agreement is continuing with Renovis. Renovis will receive a significant milestone payment and retains a co-promotion option for NXY 059 in the US. In addition, Renovis is entitled to royalties on profits from worldwide sales of the drug once commercialised. Centaur received a cash payment of $US1.25 million, and up to 30% of Renovis stock in exchange for these assets. In May 2003, AstraZeneca announced the initiation of two major phase III pivotal clinical trials to determine the effect of NXY 059 on disability and neurological recovery in acute ischemic stroke patients. The trials, known as the SAINT (Stroke-Acute-Ischaemic-NXY-Treatment) trials, will compare the efficacy and safety of a 72-hour intravenous infusion of NXY 059 given within 6 hours of the onset of symptoms vs placebo. The studies will enrol >3000 patients. The SAINT I trial will involve 200 centres across 24 countries in Europe, Asia, Australia and South Africa. The SAINT II trial will involve patients from approximately 150 sites in the US, Canada and South America. AstraZeneca is evaluating NXY 059 in a phase I clinical study in the US. Phase III trials of NXY 059 have begun in the UK and Sweden for the treatment of stroke. In November 2000, Centaur Pharmaceuticals announced that the Japanese regulatory authorities approved AstraZeneca's regulatory filings for phase I clinical studies of NXY 059 in Japan. The purpose of these studies is to investigate the safety and tolerability of 8h and 24h IV infusions of NXY 059 in 56 healthy Japanese male subjects. A secondary objective will be to evaluate the pharmacokinetics of NXY 059 in these volunteers. Collaborators: Lees KR, Zivin JA, Ashwood T, Davalos A, Davis S, Diener E, Grotta J, Lyden P, Kakarieka A, Sheth S, Shuaib A, Wasiewski W, Pocock S, Adams H, Bath P, Oakes D, Wahlgren NG, Söderberg K, Hårdemark HG, Alderfer V, Grönblad A, Emeribe U, Staples C, Bladin C, Levi C, Davis S, Dunbabin D, Schultz D, Crimmins D, Don G, Gerraty R, Thijs V, Willems C, De Deyn P, Vanhooren G, Desfontaines P, Caekebeke J, Etienne U, Stamenova P, Platikanov V, Baldaranov D, Minchev D, Tunev A, Nocheva T, Bar M, Vaclavik D, Lachmann H, Ehler E, Bauer J, Skoda O, Waberzinek G, Keller O, Urbanek K, Rektor I, Kalvach P, Meden P, Andersen G, Kaste M, Koivisto K, Rissanen A, Numminen H, Muuronen A, Amarenco P, Bonafe A, Ziegler F, Boulliat J, Moulin T, Clavelou P, Sablot D, Rollet E, Lavage P, Lucas C, Guillon B, Schneider D, Vogel P, Glahn J, Hamann GF, Weiller C, Hetzel A, Diener C, Hennerici M, Eicke M, Deuschl G, Lachenmayer L, Sander D, Witte OW, Sliwka U, Widder B, Meves S, Ng PW, Ka Sing Wong L, Cheung R, Nagy Z, Béla C, Gyula K, Csányi A, Sándor H, Lászlo C, Micieli G, Agnelli G, Gandolfo C, Carolei A, Guidetti D, Inzitari D, Merican JS, Bee Fung S, Kay--Sin T, Azman Ali R, Anderson C, Barber A, Fink J, Gommans J, Keizer K, van Erven PM, Brouwers PJ, Veering MM, Dippel D, Kwa VI, Franke CL, Kleyweg RP, Boon AE, Bjerke P, Thomassen L, Indredavik J, Hermstad B, Salvesen R, Jörgensen E, Czlonkowska A, Kuczynska A, Freyze W, Wlodek A, Wlodek A, Vasco Salgado A, Cunha L, Gonçalves G, Correia M, Ng I, Hui Meng C, Chan B, Dvorák M, Brozman M, Kurca E, Garay R, Bratislava, Vyletelka J, Nyéky M, Herényiová J, Thorne J, Maritz F, Green J, Badenhorst H, Gardiner J, Lurie D, van Graan E, Lee BC, Kim JS, Lee KH, Roh JK, Lee YS, Serena Leal J, Alvarez Sabin J, Gil Peralta A, Rubio F, Roquer J, Fernández-Bolanos R, Dávalos A, Castillo J, Guiu JM, Diez Tejedor E, Vivancos J, Lluis Martí i Vilalta J, Mostacero E, Chamorro A, Gil Nunez A, Lago A, Egido JA, Callander M, Petersson J, Terent A, Käll TB, Kostulas V, Leijd B, Karlsson JE, Karlsson S, Lees KR, Ford GA, Muir K, Barer D, Sharma A, Jenkinson D, Gray C, MacWalter R, Robinson T. BACKGROUND AND PURPOSE: NXY-059 is a free radical-trapping neuroprotectant demonstrated to reduce disability from ischemic stroke. We conducted analyses on additional end points and sensitivity analyses to confirm our findings. METHODS: We randomized 1722 patients with acute ischemic stroke to a 72-hour infusion of placebo or intravenous NXY-059 within 6 hours of stroke onset. The primary outcome was disability at 90 days, as measured by the modified Rankin Scale (mRS), a 6-point scale ranging from 0 (no residual symptoms) to 5 (bed-bound, requiring constant care). Additional and exploratory analyses included mRS at 7 and 30 days; subgroup interactions with final mRS; assessments of activities of daily living by Barthel index; and National Institutes of Health Stroke Scale (NIHSS) neurological scores at 7 and 90 days. RESULTS: NXY-059 significantly improved the distribution of the mRS disability score compared with placebo at 7, 30, and 90 days (Cochran-Mantel-Haenszel test P=0.002, 0.004, 0.038, respectively; 90-day common odds ratio 1.20; 95% CI, 1.01 to 1.42). The benefit was not attributable to any specific baseline characteristic, stratification variable or subgroup interaction. Neurological scores were improved at 7 days (odds ratio [OR], 1.46; 95% CI, 1.13, 1.89; P=0.003) and the Barthel index was improved at 7 and 30 days (OR, 1.55; 95% CI, 1.22, 1.98; P<0.0001; OR, 1.27; 95% CI, 1.01, 1.59; P=0.02). CONCLUSIONS: NXY-059 within 6 hours of acute ischemic stroke significantly reduced disability. Benefit on neurological scores and activities of daily living was detectable early but not significant at 90 days; however, our trial was underpowered to measure effects on the neurological examination. The benefit on disability is not confounded by interactions and is supported by other outcome measures. NXY-059 is a novel free radical-trapping neuroprotectant that reduces infarct size and preserves brain function in animal models of acute ischemic stroke. It is the first neuroprotectant to demonstrate a reduction in global disability in a phase III clinical trial, as measured by the modified Rankin Scale. Any effect of NXY-059 on hemostasis may be important when treating stroke patients. This phase I randomized, double-blind, placebo-controlled, 3-period crossover study compared the effect of NXY-059, desmopressin, and placebo on bleeding time, platelet aggregation, and adhesion in 30 healthy volunteers. NXY-059 did not prolong bleeding time compared with placebo: mean (SD) time for NXY-059, 369.5 seconds (125.0 seconds) versus placebo, 369.1 seconds (136.0 seconds). There were no significant effects on platelet aggregation or adhesion. At a mean unbound plasma concentration (Cu(ss)) of 335 micromol/L, NXY-059 was well tolerated, with no major safety concerns identified. In conclusion, NXY-059 does not appear to affect primary hemostasis. The SAINT II Trial, a large randomized multicenter clinical trial of the putative neuroprotectant, NXY-059, failed to demonstrate a treatment benefit in acute ischemic stroke. The further development of this agent was suspended. The implications of this outcome are considered from several perspectives, including: (1) the marginally positive antecedent trial, SAINT I, and the critical commentary stimulated by it, which called attention to its interpretively challenging primary outcome measure--a shift in the full-scale modified Rankin scale score--and to other statistical shortcomings; (2) the cogency of the STAIR recommendations, to which the development of NXY-059 closely adhered; and (3) the inherent physiochemical shortcomings of NXY-059 as a neuroprotective agent--its polar, nonlipophilic nature, poor blood-brain barrier penetrability, nonphysiological oxidation potential, and low potency. Caution is urged, however, regarding the unwarranted adoption of a nihilistic view toward neuroprotection on the part of the stroke community in view of the abundant preclinical evidence demonstrating proof-of-principle of the feasibility of neuroprotection, as well as the multiplicity of biochemical and molecular neuroprotective targets. The author offers the personal example of a translational journey in which a promising neuroprotectant agent targeting multiple injury mechanisms, high-dose albumin therapy, has proceeded successfully from preclinical studies that established efficacy through a pilot clinical trial that demonstrated safety and offered strong suggestions of clinical efficacy, leading to a large multicenter clinical trial currently in progress. The continued failure in approving new drugs for treatment of acute stroke has been recently set back by the failure of the NXY-059 (Stroke-Acute Ischemic NXY Treatment (SAINT) II) trial. The disappointment was heightened by the latter study being viewed as a most promising compound for stroke drug development program based on the preclinical data. Since the SAINT I/II development program included many of the STAIR (Stroke Therapy Academic Industry Round table) guidelines, yet have still failed to achieve the expected efficacy, there is a clear need to continue and analyze the path forward for stroke drug discovery. To this end, this review calls for a consortium approach including academia, government (FDA/NIH), and pharmaceutical industry partnerships to define this path. It is also imperative that more attention is given to the evolving discipline of Translational Medicine. A key issue in this respect is the need to devote more attention to the characteristics of the drug candidate nature-target interaction, and its relationship to pharmacodynamic treatment end points. It is equally important that efforts are spent to prove that phenotypic outcomes are linked to the purported mechanism of action of the compound. Development of technologies that allows a better assessment of these parameters, especially in in vivo models are paramount. Finally, rational patient selection and new outcome scales tailored in an adaptive design model must be evaluated. BACKGROUND AND PURPOSE: The SAINT I trial that showed a significant benefit of the neuroprotectant NXY-059 used a novel outcome for acute ischemic stroke trials: a shift toward good functional outcome on the 7-category modified Rankin scale (mRS). METHODS: We used the Cochran-Mantel-Haenszel shift test to analyze the distribution of the 90-day mRS outcomes in the NINDS and ECASS-II databases and compared the results with a dichotomized mRS outcome by logistic regression (0 to 2 vs 3 to 6, or 0 to 1 vs 2 to 6). We also stratified each dataset based on National Institutes of Health Stroke Scale baseline severity. RESULTS: Each dataset showed a statistically significant shift in the 90-day mRS distributions favoring tissue plasminogen activator (odds ratio, 1.6 for NINDS, 1.3 for ECASS-II). For ECASS-II, larger shift effects appeared in National Institutes of Health Stroke Scale 0 to 6 and 16 to 40 strata. Similarly, the mRS 0 to 2 analysis but not mRS 0 to 1 found similar treatment effects in both datasets (odds ratio, 1.6 for NINDS, 1.5 for ECASS-II) and similar variations in the low and high strata in the ECASS-II trial. NINDS found no significant treatment effects across the strata. After removing the strata at the fringes, the shift test lost significance in both datasets. CONCLUSIONS: Tissue plasminogen activator causes a beneficial shift toward wellness on the mRS in both the NINDS and ECASS-II trials, and ECASS-II would have been a positive trial according to the shift approach. However, the shift effect is not global for all treated patients and does not outperform the dichotomized 0 to 2 outcome. Patients with mild and severe deficits also shifted favorably on the mRS in the ECASS-II trial. BACKGROUND AND PURPOSE: In animal models of acute ischemic stroke (AIS), the free radical-trapping agent NXY-059 showed promise as a neuroprotectant. SAINT I and II were randomized, placebo-controlled, double-blind trials to investigate the efficacy of NXY-059 in patients with AIS. METHODS: Patients with AIS received an infusion of intravenous NXY-059 or placebo within 6 hours from the onset of stroke symptoms. A pooled individual patient analysis was prespecified to assess the overall efficacy and to examine subgroups. The primary end point was the distribution of disability scores measured on the modified Rankin scale (mRS) at 90 days. Neurologic and activities of daily living scores were investigated as secondary end points. We also evaluated whether treatment with NXY-059 would reduce alteplase-related intracranial hemorrhages. Finally, we evaluated possible predictors of good or poor outcome. RESULTS: An intent-to-treat efficacy analysis was based on 5028 patients. Baseline parameters and prognostic factors were well balanced between treatment groups. The distribution of scores on the mRS was not different in the group treated with NXY-059 (n=2438) compared with the placebo group (n=2456): odds ratio for limiting disability=1.02; 95% CI, 0.92 to 1.13 (P=0.682, Cochran-Mantel-Haenszel test). Comparisons at each level of the mRS confirmed an absence of benefit. There was no evidence of efficacy in prespecified subgroups or from the secondary outcome analyses. Mortality was equal in the 2 groups (16.7% vs 16.5%), and adverse event rates were similar. Among patients treated with alteplase, there was no decrease in rates of symptomatic or asymptomatic hemorrhage associated with NXY-059 treatment versus placebo. Subgroup analyses identified National Institutes of Health Stroke Scale score, age, markers of inflammation, blood glucose, and right-sided infarct as predictors of poor outcome. CONCLUSIONS: NXY-059 is ineffective for treatment of AIS within 6 hours of symptom onset. This is also true for subgroups and the prevention of alteplase-associated hemorrhage. Acute ischemic stroke (AIS) is a significant cause of death and disability in the United States. It has been 10 years since tissue plasminogen activator became the first medication approved by the US Food and Drug Administration for treatment for AIS. However, this treatment simply reopens arteries. The identification of deleterious cellular reactions that occur secondary to cerebral ischemia has led investigators to search for neuroprotection strategies to complement reperfusion. More than 100 human trials, including a handful of phase III trials, had failed to produce an efficacious neuroprotective agent. In 2006, the first positive trial of neuroprotection was published: the SAINT I (Stroke-Acute Ischemic NXY Treatment) study. In February 2008, the SAINT II study was published, indicating that NXY-059 was not effective for AIS treatment. Today there exists only one FDA-approved treatment for ischemic stroke; i.e., the serine protease tissue-type plasminogen activator (tPA). In the aftermath of the failed stroke clinical trials with the nitrone spin trap/radical scavenger, NXY-059, a number of articles raised the question: are we doing the right thing? Is the animal research truly translational in identifying new agents for stroke treatment? This review summarizes the current state of affairs with plasminogen activators in thrombolytic therapy. In addition to therapeutic value, potential side effects of tPA also exist that aggravate stroke injury and offset the benefits provided by reperfusion of the occluded artery. Thus, combinational options (ultrasound alone or with microspheres/obubbles, mechanical dissociation of clot, activated protein C (APC), plasminogen activator inhibitor-1 (PAI-1), neuroserpin and CDP-choline) that could offset tPA toxic side effects and improve efficacy are also discussed here. Desmoteplase, a plasminogen activator derived from the saliva of Desmodus rotundus vampire bat, antagonizes vascular tPA-induced neurotoxicity by competitively binding to low-density lipoprotein related-receptors (LPR) at the blood-brain barrier (BBB) interface, minimizing the tPA uptake into brain parenchyma. tPA can also activate matrix metalloproteinases (MMPs), a family of endopeptidases comprised of 24 mammalian enzymes that primarily catalyze the turnover and degradation of the extracellular matrix (ECM). MMPs have been implicated in BBB breakdown and neuronal injury in the early times after stroke, but also contribute to vascular remodeling, angiogenesis, neurogenesis and axonal regeneration during the later repair phase after stroke. tPA, directly or by activation of MMP-9, could have beneficial effects on recovery after stroke by promoting neurovascular repair through vascular endothelial growth factor (VEGF). However, any treatment regimen directed at MMPs must consider their pleiotropic nature and the likelihood of either beneficial or detrimental effects that might depend on the timing of the treatment in relation to the stage of brain injury. BACKGROUND AND PURPOSE: Numerous neuroprotective agents have proven effective in animal stroke studies, but every drug has failed to achieve its primary outcome when brought forward to clinical trials. We analyzed the quality and adequacy of animal studies supporting the efficacy of NXY-059 and other neuroprotective agents that are currently being investigated in phase II/III trials. METHODS: We conducted a systematic search of all neuroprotective drugs in Phase II or III trials and collected data from animal studies of focal cerebral ischemia testing agents systemically administered within 24 hours of occlusion. The methodological rigor of each individual study was evaluated using 5 criteria derived from the STAIR guidelines. The adequacy of the preclinical "package" for each drug was then evaluated by combining the results of all studies for each drug to determine which of a further 5 STAIR criteria were met before moving forward from animal to human studies. RESULTS: Our search yielded 13 agents of which 10 had published data in peer-reviewed journals. There is substantial within-drug variability in the quality of preclinical studies as well as substantial variation in the completeness of the collective preclinical literature for different drugs. There has been little or no improvement in the quality of animal studies since NXY-059, and current agents have not been subjected to a more complete preclinical evaluation. CONCLUSIONS: There is significant heterogeneity in the quality of animal testing for neuroprotective agents in stroke. Drugs in the post-SAINT era have not been subjected to more thorough preclinical evaluation. BACKGROUND: NXY-059 is a free radical-trapping neuroprotectant that has been reported to reduce infarct size and preserve brain function in experimental models of acute ischemic stroke. NXY-059 administered as an 8- or 72-hour IV infusion has been reported to be well tolerated in healthy young (age, 20-45 years) and older (55-75 years) white volunteers. NXY-059 is no longer in development following a lack of efficacy found in a Phase III trial in patients with acute ischemic stroke. OBJECTIVES: The primary objectives of this study were to determine the pharmacokinetic (PK) properties of an 8-hour IV infusion of NXY-059 in healthy Chinese volunteers and to compare those data with those previously reported in the white population, therefore exploring any differences in PK properties between the 2 ethnic groups. Secondary objectives were to evaluate PK linearity and tolerability. METHODS: This Phase I, randomized, double-blind (within dose panels), placebo-controlled study was conducted at Peking Union Medical College Hospital, Beijing, China. Healthy male and female Chinese volunteers aged 20 to 45 years were recruited. NXY-059 was administered as a continuous 8-hour IV infusion, starting with a 1-hour loading dose (dosing rate, 3 x maintece infusion rate) followed by a 7-hour maintece dose infusion. Subjects were randomly assigned, in a 3:1 ratio, to receive doses calculated (based on creatinine clearance in individual subjects) to achieve 1 of 3 concentration targets, or inactive vehicle (sodium chloride; placebo). The target unbound plasma NXY-059 concentrations during constant rate infusion (steady state) (Cu(ss)) in the 3 dose panels were 100,200, and 300 micromol/L. An explorative bridging analysis was used to compare PK data from this study with those previously reported in the white population. Linearity of NXY-059 PK properties was assessed. Tolerability was assessed using adverse events (spontaneous reporting, study staff observation, and open questioning), physical examination, including vital sign measurement; and electrocardiography and laboratory analysis. RESULTS: Thirty-six subjects were randomized (mean age, 32 years [range, 20-41 years]; mean body mass index, 22.6 kg/m(2) [range, 20-26 kg/m(2)]). The target exposures of NXY-059 were achieved (mean [SD] Cu(ss) values, 98.3 [8.9], 202.1 [18.3], and 287.9 [25.4] micromol/L, respectively). Steady-state concentrations appeared to have been reached after 4 hours. From the bridging analysis, comparison of PK properties in the 27 Chinese volunteers versus those in 28 white volunteers found similar total plasma clearance of NXY-059 (estimated Chinese:white clearance ratio, 1.077 [95% CI, 1.009-1.150]). There were no apparent differences in other PK parameters between the 2 ethnic groups. The PK properties of NXY-059 in Chinese volunteers were suggestive of linearity. A total of 7 adverse events were reported, all of mild intensity, in the NXY-059 and placebo groups (thirst and polyuria [each in 2 subjects who received NXY-059 and 1 subject who received placebo]; urinary tract infection [1 subject who received NXY-059]). CONCLUSIONS: The results from the present study suggest that the PK properties of NXY-059 were similar in the Chinese and historical white healthy volunteer populations. The nitrone compound PBN, α-phenyl-tert-butylnitrone, and closely related nitrones have anti-cancer activity in several experimental cancer models. The three experimental models most extensively studied include A) the rat choline deficiency liver cancer model, B) the rat C6 glioma model and C) the mouse APC(Min/+) colon cancer model. The two PBN-nitrones mostly studied are PBN and a PBN derivative 2,4-disulfophenyl-tert-butylnitrone, referred as OKN-007. OKN-007 is a proprietary compound that has had extensive commercial development (designated as NXY-059) for another indication, acute ischemic stroke, and after extensive clinical studies was shown to lack efficacy for this indication but was shown to be very safe for human use. This compound administered orally in the rat glioma model has potent activity in treating fully formed gliomas. In this report observations made on the PBN-nitrones in experimental cancer models will be summarized. In addition the experimental results will be discussed in the general framework of the properties of the compounds with a view to try to understand the mechanistic basis of how the PBN-nitrones act as anti-cancer agents. Possible mechanisms related to the suppression of NO production, S-nitrosylation of critical proteins and inhibition of NF-κB activation are discussed. Nitrone therapeutics has been employed in the treatment of oxidative stress-related diseases such as neurodegeneration, cardiovascular disease and cancer. The nitrone-based compound NXY-059, which is the first drug to reach clinical trials for the treatment of acute ischemic stroke, has provided promise for the development of more robust pharmacological agents. However, the specific mechanism of nitrone bioactivity remains unclear. In this review, we present a variety of nitrone chemistry and biological activity that could be implicated for the nitrone's pharmacological activity. The chemistries of spin trapping and spin adduct reveal insights on the possible roles of nitrones for altering cellular redox status through radical scavenging or nitric oxide donation, and their biological effects are presented. An interdisciplinary approach towards the development of novel synthetic antioxidants with improved pharmacological properties encompassing theoretical, synthetic, biochemical and in vitro/in vivo studies is covered. Neuroprotection aims to prevent salvageable neurons from dying. Despite showing efficacy in experimental stroke studies, the concept of neuroprotection has failed in clinical trials. Reasons for the translational difficulties include a lack of methodological agreement between preclinical and clinical studies and the heterogeneity of stroke in humans compared to homogeneous strokes in animal models. Even when the international recommendations for preclinical stroke research, the Stroke Academic Industry Roundtable (STAIR) criteria, were followed, we have still seen limited success in the clinic, examples being NXY-059 and haematopoietic growth factors which fulfilled nearly all the STAIR criteria. However, there are a number of neuroprotective treatments under investigation in clinical trials such as hypothermia and ebselen. Moreover, promising neuroprotective treatments based on a deeper understanding of the complex pathophysiology of ischemic stroke such as inhibitors of NADPH oxidases and PSD-95 are currently evaluated in preclinical studies. Further concepts to improve translation include the investigation of neuroprotectants in multicenter preclinical Phase III-type studies, improved animal models, and close alignment between clinical trial and preclinical methodologies. Future successful translation will require both new concepts for preclinical testing and innovative approaches based on mechanistic insights into the ischemic cascade. The possibility of free radical reactions occurring in biological processes led to the development and employment of novel methods and techniques focused on determining their existence and importance in normal and pathological conditions. For this reason the use of nitrones for spin trapping free radicals became widespread in the 1970s and 1980s, when surprisingly the first evidence of their potent biological properties was noted. Since then widespread exploration and demonstration of the potent biological properties of phenyl-tert-butylnitrone (PBN) and its derivatives took place in preclinical models of septic shock and then in experimental stroke. The most extensive commercial effort made to capitalize on the potent properties of the PBN-nitrones was for acute ischemic stroke. This occurred during 1993-2006, when the 2,4-disulfonylphenyl PBN derivative, called NXY-059 in the stroke studies, was shown to be safe in humans and was taken all the way through clinical phase 3 trials and then was deemed to be ineffective. As summarized in this review, because of its excellent human safety profile, 2,4-disulfonylphenyl PBN, now called OKN-007 in the cancer studies, was tested as an anti-cancer agent in several preclinical glioma models and shown to be very effective. Based on these studies this compound is now scheduled to enter into early clinical trials for astrocytoma/glioblastoma multiforme this year. The potential use of OKN-007 in combination with neurotropic compounds such as the lanthionine ketamine esters is discussed for glioblastoma multiforme as well as for various other indications leading to dementia, such as aging, septic shock, and malaria infections. There is much more research and development activity ongoing for various indications with the nitrones, alone or in combination with other active compounds, as briefly noted in this review.

Is flibanserin effetive for Hypoactive Sexual Desire Disorder?

Yes, flibanserin, a novel serotonin (5-HT)(1A) agonist and 5-HT(2A) antagonist, has been shown to increase sexual desire and reduce distress in women with Hypoactive Sexual Desire Disorder.

INTRODUCTION: Flibanserin, a novel 5-HT(1A) agonist and 5-HT(2A) antagonist, has the potential to treat sexual dysfunction. AIM: Provide historical perspective on the rationale for development of flibanserin to treat sexual dysfunction, based on post hoc analyses of data. MAIN OUTCOME MEASURES: The Arizona Sexual Experiences (ASEX) scale and the Hamilton depression rating scale (HAMD) Genital Symptoms item. METHODS: Sexual function outcomes are presented from four double-blind, randomized controlled studies involving a total of 369 men and 523 women diagnosed with Major Depressive Disorder. Each study had an active treatment arm to confirm assay sensitivity on the primary antidepressive endpoint. Two studies placebo, flibanserin (50mg bid), or fluoxetine (20mg qd) for 6 weeks and two involved placebo, flibanserin (50-100mg bid), or paroxetine (20-40mg qd) for 8 weeks. RESULTS: Individual study completion rates were 77-80%. At baseline, 38% of men and 67% of women reported sexual dysfunction. Assay sensitivity was not demonstrated in the fluoxetine trials and sexual function outcomes were inconsistent. Flibanserin and placebo were associated with low rates of treatment-emergent sexual dysfunction in women during the paroxetine studies. In one study, 70% of flibanserin-treated women with baseline sexual dysfunction reported improvement in sexual function, compared with 30% of placebo-treated women. Mean change from baseline on the HAMD "Genital Symptoms" item in one paroxetine study was significantly better among flibanserin- than placebo-treated women at weeks 4, 6, and 8 (P<0.05). Sexual function adverse events across flibanserin groups were generally comparable to placebo. CONCLUSIONS: Although these studies were not designed or powered to compare sexual function outcomes, results suggested a potential benefit of flibanserin on sexual function, particularly on female sexual desire, and provided a rationale to evaluate the efficacy of flibanserin as a treatment for female hypoactive sexual desire disorder. BACKGROUND: Flibanserin, a novel serotonin (5-HT)(1A) agonist and 5-HT(2A) antagonist, has been shown to increase sexual desire and reduce distress in women with Hypoactive Sexual Desire Disorder (HSDD). In marmoset monkeys, flibanserin has demonstrated pro-social effects on male-female pairmates, while the classic 5-HT(1A) agonist 8-OH-DPAT suppresses female sexual behavior and increases aggressive interactions between pairmates. Activation of 5-HT(1A) and 5-HT(2A) receptors is known to stimulate the hypothalamic-pituitary-adrenal (HPA) axis. This study aims to characterize the effects of repeated flibanserin and 8-OH-DPAT administration on the marmoset HPA axis and to elucidate endocrine correlates of altered marmoset pair behavior. METHODS: Adrenocorticotropic hormone (ACTH) and cortisol were examined at baseline and during 5-HT(1A) agonist and restraint challenges in 8 female marmoset monkeys receiving daily flibanserin (15mg/kg) and an additional 8 female marmosets receiving 8-OH-DPAT (0.1mg/kg) for 15-16weeks. Corresponding vehicle treatments were administered in a counterbalanced, within-subject design. All females were housed in stable male-female pairs. Treatment-induced changes in ACTH and cortisol levels were correlated with previously assessed marmoset pair behavior. RESULTS: While morning basal cortisol levels and HPA responses to a 5-HT(1A) agonist challenge were not altered by chronic flibanserin or 8-OH-DPAT, both treatments increased the responsiveness of the marmoset HPA axis to restraint. Enhanced ACTH responses to restraint correlated with reduced sexual receptivity and increased aggression in 8-OH-DPAT-, but not in flibanserin-treated female marmosets. CONCLUSIONS: Unaltered HPA responses to a 5-HT(1A) agonist challenge after chronic flibanserin and 8-OH-DPAT treatments indicate little or no de-sensitization of the HPA axis to repeated 5-HT(1A) manipulation. Chronic 8-OH-DPAT, but not flibanserin, leads to aggravated ACTH responses to stress that may contribute to anti-sexual and anti-social behavior between 8-OH-DPAT-treated females and their male pairmates. Despite similar flibanserin and 8-OH-DPAT induced ACTH responses to restraint stress, flibanserin-treated females show unchanged cortisol profiles. This is possibly due to flibanserin's regional selectivity in 5-HT(1A) activation and concurrent 5-HT(2A) inhibition. The contrasting restraint-related cortisol responses emulate contrasting behavioral phenotypes of diminished pair-bond of 8-OH-DPAT-treated females compared to the more affiliative pair-bond of flibanserin-treated females. INTRODUCTION: Flibanserin is a mixed 5-HT1A agonist/5-HT2A antagonist that has been developed for the treatment of hypoactive sexual desire disorder in women. AIM: To assess the acute and chronic dose-response effects of flibanserin on measures of sexual desire and copulation in ovariectomized rats primed with estradiol benzoate (EB) alone or in combination with progesterone (P). METHODS: In Experiment 1, sexually experienced ovariectomized (OVX) rats at one testing site were rendered fully sexually receptive with EB + P priming and tested weekly with a sexually active male in bi-level pacing chambers following daily flibanserin treatment for 28 days. In Experiment 2, sexually experienced OVX rats at a different testing site received EB alone and were tested weekly with sexually active males following daily flibanserin treatment. MAIN OUTCOME MEASURES: Female appetitive behaviors (solicitations, hops and darts, anogenital investigations), defensive behaviors, pacing, lordosis, and male copulatory responses (intromissions and ejaculations) were measured during each 30-minute copulation test. RESULTS: Acute flibanserin or 1 week of chronic flibanserin treatment did not modify sexual responses in fully (EB + P) or partially (EB-alone) primed females. After 2 weeks of chronic treatment, fully primed females displayed significantly more solicitations than the three other groups. After 3 weeks of chronic treatment, a significant increase in female solicitations was observed in both hormone-treatment groups. CONCLUSION: This study shows the first evidence that chronic, but not acute, flibanserin treatment augments appetitive sexual behaviors in OVX female rats primed with EB + P or EB alone. Given the positive effect of flibanserin in clinical trials, these results confirm previous reports that solicitations in the female rat are a predictive animal model of human female sexual desire. OBJECTIVE: This study aimed to assess the efficacy and safety of flibanserin, a serotonin receptor 1A agonist/serotonin receptor 2A antagonist, in postmenopausal women with hypoactive sexual desire disorder (HSDD). METHODS: Naturally postmenopausal women with HSDD received flibanserin 100 mg once daily at bedtime (n = 468) or placebo (n = 481) for 24 weeks. Co-primary endpoints were changes from baseline to week 24 in the number of satisfying sexual events (SSEs) across 28 days and in the Female Sexual Function Index (FSFI) desire domain score. Secondary endpoints included change from baseline in Female Sexual Distress Scale-Revised (FSDS-R) Item 13 score (which assesses distress due to low sexual desire), FSDS-R total score, and FSFI total score. The Patient Benefit Evaluation was asked on treatment discontinuation. RESULTS: There were significant improvements with flibanserin versus placebo in the mean (SE) changes in the number of SSEs (1.0 [0.1] vs 0.6 [0.1]), FSFI desire domain score (0.7 [0.1] vs 0.4 [0.1]), FSDS-R Item 13 score (-0.8 [0.1] vs -0.6 [0.1]), FSDS-R total score (-8.3 [0.6] vs -6.3 [0.6]), and FSFI total score (4.2 [0.4] vs 2.7 [0.4]; all P < 0.01). More women on flibanserin (37.6%) than women on placebo (28.0%) reported experiencing meaningful benefits from the study medication on treatment discontinuation. The most frequent adverse events associated with flibanserin were dizziness, somnolence, nausea, and headache. CONCLUSIONS: In naturally postmenopausal women with HSDD, flibanserin, compared with placebo, has been associated with improvement in sexual desire, improvement in the number of SSEs, and reduced distress associated with low sexual desire, and is well tolerated. Hypoactive sexual desire disorder (HSDD) is the most commonly described form of female sexual dysfunction. There is currently no pharmacological therapy approved to treat HSDD, and therefore, there is an unmet medical need for the development of efficacious treatment alternatives. Flibanserin is a novel, non-hormonal drug for the treatment of HSDD in pre- and postmenopausal women, although the application submitted to the U.S. Food and Drug Administration by Sprout Pharmaceuticals is only for premenopausal women. Flibanserin works by correcting an imbalance of the levels of the neurotransmitters that affect sexual desire. More specifically, flibanserin increases dopamine and norepinephrine, both responsible for sexual excitement, and decreases serotonin, responsible for sexual inhibition. Clinically, flibanserin has exhibited some encouraging results in terms of its ability to increase the frequency of satisfying sexual events, and the intensity of sexual desire. However, adverse events such as dizziness, nausea, fatigue and somnolence, typical of a centrally acting drug, are also frequently related to flibanserin treatment.

List available biomedical question answering systems.

We live in an age of access to more information than ever before. The exponential growth in the volume of publications in the biomedical domain has made it impossible for an individual to keep pace with the advances. Thus, there is a need for intelligent information retrieval systems that can summarize relevant and reliable textual sources to satisfy a user's query. Question answering is a specialized type of information retrieval with the aim of returning precise short answers to queries posed as natural language questions. This accentuates the need for fast and accurate biomedical question answering systems. In this paper we introduce INDOC -- a biomedical question answering system based on novel ideas of indexing and extracting the answer to the questions posed. Increased access to information allows for more informed and empowered researchers, while information overload becomes an increasingly serious risk. INDOC displays the results in clusters to help the user arrive the most relevant set of documents quickly. Evaluation was done against the standard OHSUMED test collection. We present a review and comparison of three biomedical question answering systems: askHERMES, EAGLi ( http://eagl.unige.ch/EAGLi/ ), and HONQA ( http://services.hon.ch/cgi-bin/QA10/qa.pl ).

The Internet is having a profound impact on physicians' medical decision making. One recent survey of 277 physicians showed that 72% of physicians regularly used the Internet to research medical information and 51% admitted that information from web sites influenced their clinical decisions. This paper describes the first cognitive evaluation of four state-of-the-art Internet search engines: Google (i.e., Google and Scholar.Google), MedQA, Onelook, and PubMed for answering definitional questions (i.e., questions with the format of "What is X?") posed by physicians. Onelook is a portal for online definitions, and MedQA is a question answering system that automatically generates short texts to answer specific biomedical questions. Our evaluation criteria include quality of answer, ease of use, time spent, and number of actions taken. Our results show that MedQA outperforms Onelook and PubMed in most of the criteria, and that MedQA surpasses Google in time spent and number of actions, two important efficiency criteria. Our results show that Google is the best system for quality of answer and ease of use. We conclude that Google is an effective search engine for medical definitions, and that MedQA exceeds the other search engines in that it provides users direct answers to their questions; while the users of the other search engines have to visit several sites before finding all of the pertinent information. The exponential growth in the volume of publications in the biomedical domain has made it impossible for an individual to keep pace with the advances. Even though evidence-based medicine has gained wide acceptance, the physicians are unable to access the relevant information in the required time, leaving most of the questions uswered. This accentuates the need for fast and accurate biomedical question answering systems. In this paper we introduce INDOC--a biomedical question answering system based on novel ideas of indexing and extracting the answer to the questions posed. INDOC displays the results in clusters to help the user arrive the most relevant set of documents quickly. Evaluation was done against the standard OHSUMED test collection. Our system achieves high accuracy and minimizes user effort. We live in an age of access to more information than ever before. This can be a double-edged sword. Increased access to information allows for more informed and empowered researchers, while information overload becomes an increasingly serious risk. Thus, there is a need for intelligent information retrieval systems that can summarize relevant and reliable textual sources to satisfy a user's query. Question answering is a specialized type of information retrieval with the aim of returning precise short answers to queries posed as natural language questions. We present a review and comparison of three biomedical question answering systems: askHERMES (http://www.askhermes.org/), EAGLi (http://eagl.unige.ch/EAGLi/), and HONQA (http://services.hon.ch/cgi-bin/QA10/qa.pl).

Which dediodinases are present in kidney?

Type 1 and Type 3 deiodinases are both present in liver

When activated by dithiothreitol, iodothyronine 5'-deiodinase (I-5'D) activity in kidney microsomes is less sensitive to inhibition by propylthiouracil (PTU) and iopanoate (IOP) at omolar, compared to micromolar, substrate concentrations. The enzymatic activities at omolar substrate concentrations are, however, completely eliminated in the presence of a combination of 10 microM IOP and 100 microM PTU. In this report we present evidence that 1) the relative PTU insensitivity results from the residual activities of the high Km enzyme which, while being very sensitive to PTU inhibition at micromolar substrate concentrations, becomes progressively less PTU sensitive as substrate concentrations decline relative to its Km; and 2) the relative IOP insensitivity is due to the presence in kidney microsomes of a low Km enzyme which is relatively insensitive to IOP, but highly sensitive to inhibition by PTU. Classifying the deiodinases on the basis of PTU sensitivity, therefore, requires that not only the thiol concentrations, but, as in the case of the type I enzyme, also the substrate concentrations be specified. The PTU resistance of the type I enzyme at omolar substrate concentrations suggests a role of this enzyme in T3 neogenesis in PTU-treated animals. We have examined the influence of assay conditions on the 6-n-propyl-2-thiouracil (PTU) sensitivity of the iodothyronine 5'-deiodinase in brown adipose tissue (BAT) from hypothyroid rats. These results were compared with similar studies of 5'-deiodinase activity in kidney microsomes from euthyroid animals. Even though BAT microsomes contain largely type II (PTU-insensitive) deiodinase activity, the 5'-deiodination of T4 can be inhibited by PTU if the dithiothreitol (DTT) concentration in the assay is reduced to 5 mM or less. The apparent Ki for PTU of BAT microsomes was 4.3 mM at 5.0 mM DTT and 0.41 mM at 0.5 mM DTT. The kinetics of inhibition were noncompetitive. With kidney microsomes, PTU inhibition of rT3 5'-deiodination was both time and enzyme/substrate ratio dependent. For example, using 1 microgram microsomal protein, 2 nM rT3, and 5 mM DTT, the inhibitory effect of PTU was not maximal until 12 min after PTU addition. At stable reaction velocities PTU inhibition was uncompetitive, and the Ki was about 1 microM. Deiodination by kidney microsomes was completely inhibited by 50 microM PTU. Even though it is possible to inhibit the type II 5'-deiodinase activity with high concentrations of PTU (in the presence of low DTT concentrations), the deiodinase in kidney is about 1000-fold more sensitive to PTU. By these criteria the kidney microsome 5'-deiodinase is type I. In the present study the hypothesis was tested that N-bromoacetyl-3,3',5-[125I]triiodothyronine (BrAc[125I]T3) is a useful affinity label for both type I and type III iodothyronine deiodinases (ID-I and ID-III). Therefore, the microsomal fractions of various rat tissues were tested for ID-I and ID-III activities, and microsomal proteins were labeled with BrAc[125I]T3 and analyzed by SDS-PAGE. In agreement with previous observations, high ID-I activities were found in liver, kidney and thyroid, and high ID-III activities in brain, in particular fetal brain, and placenta. SDS-PAGE of BrAc[125I]T3-labeled microsomes showed a prominent radioactive approximately 27 kDa protein (p27) in liver, kidney and thyroid, which was previously identified as ID-I, and a approximately 32 kDa protein (p32) in brain, in particular fetal brain, and placenta. A good correlation was found between the affinity labeling of p32 and the inactivation of ID-III by BrAcT3, suggesting that p32 represents ID-III or a subunit thereof. After treatment of microsomes with 0.05% deoxycholate or carbonate buffer (pH 11.5) p32 was still labeled by BrAc[125I]T3, indicating that p32 is a transmembrane protein. Although 3,3',5'-triiodothyronine (rT3) is not a substrate for ID-III, p32 was readily labeled with BrAc[125I]rT3. Labeling of p32 in rat brain microsomes by BrAc[125I]rT3 was not affected by addition of 100 microM unlabeled thyroxine (T4) or T3, whereas deiodination of [125I]T3 by ID-III was inhibited by 91 and 96% in the presence of 1 microM T4 and T3, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

What is the presumed key event in Fanconi anemia pathogenesis?

Monoubiquitination of the Fanconi anaemia protein FANCD2 is a key event leading to repair of interstrand cross-links. Failure of FANCD2 monoubiquitination by the nuclear FA protein complex has a severe impact on the DNA repair functions of cells.

Fanconi anemia (FA) is characterized by congenital abnormalities, bone marrow failure, chromosome fragility, and cancer susceptibility. Eight FA-associated genes have been identified so far, the products of which function in the FA/BRCA pathway. A key event in the pathway is the monoubiquitination of the FANCD2 protein, which depends on a multiprotein FA core complex. In a number of patients, spontaneous genetic reversion can correct FA mutations, leading to somatic mosaicism. We analyzed the FA/BRCA pathway in 53 FA patients by FANCD2 immunoblots and chromosome breakage tests. Strikingly, FANCD2 monoubiquitination was detected in peripheral blood lymphocytes (PBLs) in 8 (15%) patients. FA reversion was further shown in these patients by comparison of primary fibro-blasts and PBLs. Reversion was associated with higher blood counts and clinical stability or improvement. Once constitutional FANCD2 patterns were determined, patients could be classified based on the level of FA/BRCA pathway disruption, as "FA core" (upstream inactivation; n = 47, 89%), FA-D2 (n = 4, 8%), and an unidentified downstream group (n = 2, 4%). FA-D2 and unidentified group patients were therefore relatively common, and they had more severe congenital phenotypes. These results show that specific analysis of the FA/BRCA pathway, combined with clinical and chromosome breakage data, allows a comprehensive characterization of FA patients. Fanconi anemia is an autosomal recessive syndrome characterized by diverse clinical symptoms, hypersensitivity to DNA crosslinking agents, chromosomal instability and susceptibility to cancer. Fanconi anemia has at least 11 complementation groups (A, B, C, D1, D2, E, F, G, I, J, L); the genes mutated in 8 of these have been identified. The gene BRCA2 was suggested to underlie complementation group B, but the evidence is inconclusive. Here we show that the protein defective in individuals with Fanconi anemia belonging to complementation group B is an essential component of the nuclear protein 'core complex' responsible for monoubiquitination of FANCD2, a key event in the DNA-damage response pathway associated with Fanconi anemia and BRCA. Unexpectedly, the gene encoding this protein, FANCB, is localized at Xp22.31 and subject to X-chromosome inactivation. X-linked inheritance has important consequences for genetic counseling of families with Fanconi anemia belonging to complementation group B. Its presence as a single active copy and essentiality for a functional Fanconi anemia-BRCA pathway make FANCB a potentially vulnerable component of the cellular machinery that maintains genomic integrity. Recent studies show overlap between Fanconi anemia (FA) proteins and those involved in DNA repair mediated by homologous recombination (HR). However, the mechanism by which FA proteins affect HR is unclear. FA proteins (FancA/C/E/F/G/L) form a multiprotein complex, which is responsible for DNA damage-induced FancD2 monoubiquitination, a key event for cellular resistance to DNA damage. Here, we show that FANCD2-disrupted DT40 chicken B-cell line is defective in HR-mediated DNA double-strand break (DSB) repair, as well as gene conversion at the immunoglobulin light-chain locus, an event also mediated by HR. Gene conversions occurring in mutant cells were associated with decreased nontemplated mutations. In contrast to these defects, we also found increased spontaneous sister chromatid exchange (SCE) and intact Rad51 foci formation after DNA damage. Thus, we propose that FancD2 promotes a subpathway of HR that normally mediates gene conversion by a mechanism that avoids crossing over and hence SCEs. Monoubiquitination of the Fanconi anaemia protein FANCD2 is a key event leading to repair of interstrand cross-links. It was reported earlier that FANCD2 co-localizes with NBS1. However, the functional connection between FANCD2 and MRE11 is poorly understood. In this study, we show that inhibition of MRE11, NBS1 or RAD50 leads to a destabilization of FANCD2. FANCD2 accumulated from mid-S to G2 phase within sites containing single-stranded DNA (ssDNA) intermediates, or at sites of DNA damage, such as those created by restriction endonucleases and laser irradiation. Purified FANCD2, a ring-like particle by electron microscopy, preferentially bound ssDNA over various DNA substrates. Inhibition of MRE11 nuclease activity by Mirin decreased the number of FANCD2 foci formed in vivo. We propose that FANCD2 binds to ssDNA arising from MRE11-processed DNA double-strand breaks. Our data establish MRN as a crucial regulator of FANCD2 stability and function in the DNA damage response. Fanconi Anemia (FA) is a genetic disorder characterized by the inability of patient cells to repair DNA damage caused by interstrand crosslinking agents. There are currently 14 verified FA genes, where mutation of any single gene prevents repair of DNA interstrand crosslinks (ICLs). The accumulation of ICL damage results in genome instability and patients having a high predisposition to cancers. The key event of the FA pathway is dependent on an eight-protein core complex (CC), required for the monoubiquitination of each member of the FANCD2-FANCI complex. Interestingly, the majority of patient mutations reside in the CC. The molecular mechanisms underlying the requirement for such a large complex to carry out a monoubiquitination event remain a mystery. This paper documents the extensive efforts of researchers so far to understand the molecular roles of the CC proteins with regard to its main function in the FA pathway, the monoubiquitination of FANCD2 and FANCI.

What is the effect of Allopurinol on asphyxia in neonates?

Allopurinol was shown in a number of clinical trial to be safe and effective for treatment of neonatal asphyxia. Allopurinol improves short-term and long-term clinical outcomes of neonatal asphyxia. Allopurinol should be administered as soon as possible. Postulated mechanism of allopurinol action in this setting is prevention of hypoxia-perfusion injury by reduction of free radical formation.

OBJECTIVE: Free radical-induced postasphyxial reperfusion injury has been recognized as an important cause of brain tissue damage. We investigated the effect of high-dose allopurinol (ALLO; 40 mg/kg), a xanthine-oxidase inhibitor and free radical scavenger, on free radical status in severely asphyxiated newborns and on postasphyxial cerebral perfusion and electrical brain activity. METHODS: Free radical status was assessed by serial plasma determination of nonprotein-bound iron (microM), antioxidative capacity, and malondialdehyde (MDA; microM). Cerebral perfusion was investigated by monitoring changes in cerebral blood volume (delta CBV; mL/100 g brain tissue) with near infrared spectroscopy; electrocortical brain activity (ECBA) was assessed in microvolts by cerebral function monitor. Eleven infants received 40 mg/kg ALLO intravenously, and 11 infants served as controls (CONT). Plasma nonprotein-bound iron, antioxidative capacity, and MDA were measured before 4 hours, between 16 and 20 hours, and at the second and third days of age. Changes in CBV and ECBA were monitored between 4 and 8, 16 and 20, 58 and 62, and 104 and 110 hours of age. RESULTS: Six CONT and two ALLO infants died after neurologic deterioration. No toxic side effects of ALLO were detected. Nonprotein-bound iron (mean +/- SEM) in the CONT group showed an initial rise (18.7 +/- 4.6 microM to 21.3 +/- 3.4 microM) but dropped to 7.4 +/- 3.5 microM at day 3; in the ALLO group it dropped from 15.5 +/- 4.6 microM to 0 microM at day 3. Uric acid was significantly lower in ALLO-treated infants from 16 hours of life on. MDA remained stable in the ALLO group, but increased in the CONT group at 8 to 16 hours versus < 4 hours (mean +/- SEM; 0.83 +/- 0.31 microM vs 0.50 +/- 0.14 microM). During 4 to 8 hours, delta CBV-CONT showed a larger drop than delta CBV-ALLO from baseline. During the subsequent registrations CBV remained stable in both groups. ECBA-CONT decreased, but ECBA-ALLO remained stable during 4 to 8 hours of age. Neonates who died had the largest drops in CBV and ECBA. CONCLUSION: This study suggests a beneficial effect of ALLO treatment on free radical formation, CBV, and electrical brain activity, without toxic side effects. OBJECTIVE: To investigate whether postnatal allopurinol would reduce free radical induced reperfusion/reoxygenation injury of the brain in severely asphyxiated neonates. METHOD: In an interim analysis of a randomised, double blind, placebo controlled study, 32 severely asphyxiated infants were given allopurinol or a vehicle within four hours of birth. RESULTS: The analysis showed an unaltered (high) mortality and morbidity in the infants treated with allopurinol. CONCLUSION: Allopurinol treatment started postnatally was too late to reduce the early reperfusion induced free radical surge. Allopurinol administration to the fetus with (imminent) hypoxia via the mother during labour may be more effective in reducing free radical induced post-asphyxial brain damage. In newborn infants, allopurinol is being tested as a free radical scavenger to prevent brain damage caused by reperfusion and oxygenation after perinatal hypoxia and ischemia (birth asphyxia). To develop rational dosing schemes for future studies, knowledge of the pharmacokinetics in this patient group is essential. In the present study, a population pharmacokinetic model was designed and validated for allopurinol in this specific patient group. One-compartment and 2-compartment models were fitted to plasma concentration time data of 24 newborns entered in 2 clinical trials using nonlinear mixed effects modeling. A bootstrap procedure was performed to check the robustness of the model. The data were best described using a 1-compartment model with linear elimination. Estimated pharmacokinetic parameters were volume of the central compartment (V, 0.79 L/kg) and total body clearance (CL, 0.078 L/h/kg), with 42% and 60% interindividual variability, respectively. The median values for these parameters of 1000 bootstrap replicates were very similar (95% confidence intervals were 0.67 to 0.96 and 0.054 to 0.10 for V and CL, respectively), indicating the robustness of the model. A population pharmacokinetic model has been designed and validated which adequately describes the data of 2 clinical studies in critically ill newborn infants. The model will be used to design dosing strategies for future evaluation of the benefits of allopurinol in these patients. OBJECTIVE: Free-radical-induced reperfusion injury has been recognised as an important cause of brain tissue damage after birth asphyxia. Allopurinol reduces the formation of free radicals, thereby potentially limiting the amount of hypoxia-reperfusion damage. In this study the long-term outcome of neonatal allopurinol treatment after birth asphyxia was examined. DESIGN: Follow-up of 4 to 8 years of two earlier performed randomised controlled trials. SETTING: Leiden University Medical Center, University Medical Center Groningen and University Medical Center Utrecht, The Netherlands. PATIENTS: Fifty-four term infants were included when suffering from moderate-to-severe birth asphyxia in two previously performed trials. INTERVENTION: Infants either received 40 mg/kg allopurinol (with an interval of 12 h) starting within 4 h after birth or served as controls. MAIN OUTCOME MEASURES: Children, who survived, were assessed with the Wechsler Preschool and Primary Scales of Intelligence test or Wechsler Intelligence Scale for Children and underwent a neurological examination. The effect of allopurinol on severe adverse outcome (defined as mortality or severe disability at the age of 4-8 years) was examined in the total group of asphyxiated infants and in a predefined subgroup of moderately asphyxiated infants (based on the amplitude integrated electroencephalogram). RESULTS: The mean age during follow-up (n=23) was 5 years and 5 months (SD 1 year and 2 months). There were no differences in long-term outcome between the allopurinol-treated infants and controls. However, subgroup analysis of the moderately asphyxiated group showed significantly less severe adverse outcome in the allopurinol-treated infants compared with controls (25% vs 65%; RR 0.40, 95%CI 0.17 to 0.94). CONCLUSIONS: The reported data may suggest a (neuro)protective effect of neonatal allopurinol treatment in moderately asphyxiated infants. New knowledge of the pathophysiology and evolution of hypoxic-ischemic brain injuries has made feasible interventions to improve clinical outcomes for newborns surviving birth asphyxia. Brain injury following hypoxic-ischemic insult is a complex process evolving over hours to days, which provides a unique window of opportunity for neuroprotective treatment interventions. The specific pathologic processes preceding the onset of irreversible cerebral injury appear to be a combination of several mechanisms that are variable according to the severity and duration of the insult and to biochemical modifications in the brain. Advances in neuroimaging, brain monitoring techniques, and tissue biomarkers have improved the ability to diagnose, monitor, and care for newborn infants with neonatal encephalopathy, as well as to predict their outcome. The role of oxidative stress in newborn morbidity with respect to the higher risk of free radical damage in these babies is growing. However, challenges remain in early identification of infants at risk for neonatal encephalopathy, determination of timing and extent of hypoxic-ischemic brain injury, as well as optimal management and treatment duration. Potential neuroprotective strategies targeting different pathways leading to neuronal cell death in response to hypoxic-ischemic insult have been investigated: hypothermia, erythropoietin, iminobiotin, deferioxamine, magnesium, allopurinol, xenon, melatonin and statins. Hypothermia is currently the only recognized beneficial therapy. However, many infants still develop significant adverse outcomes. It is becoming evident that the association of moderate hypothermia with neuroprotective drugs may enhance the outcome. By virtue of their pleiotropic effects without toxic effects, melatonin and statins may act at different levels of the multiple mechanisms responsible for the progression of the neurodegenerative process and represent promising neuroprotectants, alone or as additional adjunctive therapy, for reducing brain injury and its long-term sequelae in infants. More clinical studies are needed to clarify the role of these potential neuroprotective drugs.

Is recommended the use of perioperative treatment with thyroid hormone therapy in patients undergoing coronary artery bypass grafting?

Currently there is no substantial evidence to justify routine use of thyroid hormones in patients undergoing coronary artery bypass grafting.

The treatment of hypothyroidism in patients undergoing coronary artery bypass surgery is a difficult clinical problem. To determine perioperative thyroid replacement therapy in patients with hypothyroidism, plasma total thyroxine (T4), total triiodothyroxine (T3), free T4, free T3 and thyroid-stimulating hormone levels were measured preoperatively and at 1, 2, 3, 7, and 14 days after operation in 9 patients with hypothyroidism and were compared with levels in 14 patients with normal thyroid function who underwent coronary bypass surgery. In the normal control group, total T4 decreased to its lowest level on the 1st postoperative day and then increased gradually to the preoperative level at 7 days. Total T4 remained within the normal range throughout the entire postoperative course. In 6 patients with hypothyroidism who were treated with thyroid hormone before surgery, total T4 decreased immediately after operation and only increased after starting thyroid replacement therapy. In 3 hypothyroid patients without prior thyroid replacement, total T4 showed a change similar to patients in the control group but remained below the normal range until starting thyroid replacement therapy. Coronary bypass surgery was performed safely in patients with hypothyroidism. Preoperative thyroid replacement with suboptimal doses was safe in patients with severe hypothyroidism. Adequate postoperative thyroid replacement was achieved in all patients without complications. Thyroid hormone alterations (known as the "sick-euthyroid syndrome") are common following major surgery, but the time course for appearance and recovery from these alterations has not previously been longitudinally studied in a large group of surgical patients. The authors prospectively studied 59 patients undergoing major surgery (coronary artery bypass grafting, pneumonectomy, or subtotal colectomy). Compared with preoperative values, the mean serum T4, T3, free T3, and TSH concentrations decreased significantly (p less than 0.05) following surgery. Serum reverse T3 and T3 resin uptake index increased, while free T4 levels remained unchanged. These changes were seen within 6 hours of surgery and normalized by 1 week after surgery. Although the serum TSH response to TRH was normal before and after surgery in 56 of the 59 patients, the maximal TRH-induced increase in serum TSH and the integrated serum TSH response to TRH were suppressed in the early perioperative period. This postoperative TSH suppression correlated with elevated postoperative plasma dopamine concentrations (r = 0.57, p less than 0.05). Three patients with compensated primary hypothyroidism were detected in the study and represent the first documentation of serial thyroid hormone and TSH levels in hypothyroid patients undergoing major surgery. These patients had similar changes in thyroid hormone values compared with euthyroid patients. The serum TSH response to TRH was suppressed into the normal range in two of these patients on the day following surgery. The authors conclude that the sick-euthyroid syndrome occurs within a few hours of major surgery and remits with convalescence. Postoperative decreases in serum TSH may mask the diagnosis of hypothyroidism. Surgical consultants should be aware of these rapid postoperative changes so that thyroid function tests are properly interpreted in patients who have undergone major surgery. BACKGROUND: Thyroid hormone has many effects on the cardiovascular system. During and after cardiopulmonary bypass, serum triiodothyronine concentrations decline transiently, which may contribute to postoperative hemodynamic dysfunction. We investigated whether the perioperative administration of triiodothyronine (liothyronine sodium) enhances cardiovascular performance in high-risk patients undergoing coronary-artery bypass surgery. METHODS: We administered triiodothyronine or placebo to 142 patients with coronary artery disease and depressed left ventricular function. The hormone was administered as an intravenous bolus of 0.8 microgram per kilogram of body weight when the aortic cross-clamp was removed after the completion of bypass surgery and then as an infusion of 0.113 microgram per kilogram per hour for six hours. Clinical and hemodynamic responses were serially recorded, as was any need for inotropic or vasodilator drugs. RESULTS: The patients' preoperative serum triiodothyronine concentrations were normal (mean [+/- SD] value, 81 +/- 22 ng per deciliter [1.2 +/- 0.3 nmol per liter]), and they decreased by 40 percent (P < 0.001) 30 minutes after the onset of cardiopulmonary bypass. The concentrations in patients given intravenous triiodothyronine became supranormal and were significantly higher than those in patients given placebo (P < 0.001). However, the concentrations were once again similar in the two groups 24 hours after surgery. The mean postoperative cardiac index was higher in the triiodothyronine group (2.97 +/- 0.72 vs. 2.67 +/- 0.61 liters per minute per square meter of body-surface area, P = 0.007), and systemic vascular resistance was lower (1073 +/- 314 vs. 1235 +/- 387 dyn.sec.cm-5, P = 0.003). The two groups did not differ significantly in the incidence of arrhythmia or the need for therapy with inotropic and vasodilator drugs during the 24 hours after surgery, or in perioperative mortality and morbidity. CONCLUSIONS: Raising serum triiodothyronine concentrations in patients undergoing coronary-artery bypass surgery increases cardiac output and lowers systemic vascular resistance, but does not change outcome or alter the need for standard postoperative therapy. A controversy persists as to whether cardiopulmonary bypass (CPB) decreases plasma levels of triiodothyronine (T3), thereby justifying peri-operative administration of T3 to improve haemodynamic recovery. To examine the effects of T3 therapy on post-CPB haemodynamics and to determine whether the potential inotropic effects of T3 are mediated by an increase in beta-adrenergic responsiveness, a prospective, randomized, double-blind, placebo-controlled study was performed in 20 patients undergoing cardiac surgery with CPB. T3 or placebo solution (10 patients in each group) was given intravenously at the time of aortic unclamping and 4, 8, 12 and 20 h thereafter. End points included (1) thyroid hormone levels measured by radioimmunoassay (2) standard haemodynamic parameters (3) the density of lymphocyte beta-adrenoceptors measured by a radioligand (125I-iodocyanopindolol) binding technique. Post-CPB values (cross clamp removal) of T3 (pg.ml-1) were not significantly decreased compared with pre-CPB values: 3.3 +/- 0.2 vs 3.1 +/- 0.2 in controls and 3.3 +/- 0.4 vs 3.7 +/- 0.6 in T3-treated patients, respectively. The haemodynamic parameters were no different between the two groups at any postoperative time point. Likewise, density and affinity of lymphocyte beta-adrenoceptors were not significantly different from pre-operative values in either group. Thus, there seems to be no sound justification for a routine use of T3 in patients undergoing open-heart procedures. OBJECTIVE: To test the hypothesis that triiodothyronine (T(3)) administration improves hemodynamic variables and decreases inotropic drug requirements in cardiac surgery patients. DESIGN: Prospective, randomized, double-blind, placebo-controlled trial. SETTING: Tertiary care medical center. PATIENTS: A total of 211 patients undergoing coronary artery surgery at high risk for requiring inotropic drug support. INTERVENTION: At release of aortic cross-clamp, patients were randomized to an intravenous infusion of T(3) (0.8 microg/kg followed by 0.12 microg.kg(-1).h(-1) for 6 hours), dopamine (positive control, 5 microg.kg(-1).min(-1) for 6 hours) or placebo. MAIN OUTCOME MEASURES: Perioperative hemodynamic variables, inotropic support requirements, and serum T(3) concentrations. RESULTS: Mean+/-SEM free T(3) serum concentrations decreased significantly during cardiopulmonary bypass in all groups (from 0.0035+/-0.0001 nmol/L [0.23+/-0.01 ng/dL] to 0.001+/-0.0001 nmol/L [0.7+/- 0.00 ng/dL]; P=.001) and increased to 0.0133+/-0.0004 nmol/L [0.87+/-0.03 ng/dL] (twice normal range; P<.001) following initiation of intravenous T(3). Intravenous T(3) did not change hemodynamic variables or inotropic drug requirements; however, heart rate increased (P<.001), and a trend toward decreased use of inotropic agents was demonstrated in the dopamine group. CONCLUSIONS: Triiodothyronine administration prevents decreases in serum thyroid hormone concentrations associated with cardiopulmonary bypass. Intravenous T(3) does not have dramatic effects on hemodynamic variables in this setting as has been previously suggested. Although mild effects on myocardial performance may exist, we cannot recommend at this time the routine use of intravenous T(3) as an inotropic agent in patients undergoing coronary artery bypass graft surgery. The outcome of coronary bypass surgery was analyzed in 25 patients who were on thyroxin replacement therapy for chronic thyroid disorders at the time of operation. It was hypothesized that if such patients were given only their routine dose of thyroxin on the day of surgery, hemodynamic and cardiorespiratory recovery may be poor. All the patients on thyroxin replacement therapy were given their routine dose of thyroxin orally or via a nasogastric tube in the perioperative period. No supplemental dose was used. Based on preoperative levels of thyroid stimulating hormone, 68% of these patients were biochemically hypothyroid prior to surgery. Analysis of a large number of variables showed no difference in outcome against a control group who had no previous thyroid problems. We conclude that routine thyroxin administration is all that is required for a satisfactory outcome in patients undergoing coronary bypass surgery while on thyroxin replacement therapy. A prospective randomized and double-blind study was performed to evaluate whether perioperative triiodothyronine administration has any effect on cardiovascular performance after coronary artery bypass surgery. Sixty patients were assigned to 2 groups of 30 each. When crossclamping ended, group A received an intravenous bolus of triiodothyronine, followed by infusion for 6 hours. Group B received a placebo. Serum triiodothyronine levels and hemo-dynamic parameters were serially measured. Mean postoperative cardiac index was slightly, but not significantly, higher in group A, whereas systemic vascular resistance was significantly lower in group A. Compared with preoperative values, serum triiodothyronine levels dropped significantly in group B at the end of cardiopulmonary bypass and remained low 12 hours postoperatively, while levels rose significantly in group A. No significant differences were detected between the groups in the incidence of arrhythmia, the need for inotropic support, intensive care unit stay, mortality, and morbidity. Perioperative administration of triiodothyronine increased cardiac output slightly and decreased systemic vascular resistance, but it had no effect on operative outcome. Routine use after coronary surgery is thus not recommended. BACKGROUND: The impact of thyroid disease on patients undergoing coronary artery bypass grafting has been reported in only small series of selected patients. METHODS: We investigated 30-day mortality of patients on thyroxine replacement therapy undergoing isolated coronary artery bypass grafting from 1993 to 2000 and identified variables of importance for outcome. RESULTS: A total of 3,631 patients (606 women) had isolated coronary artery bypass grafting of whom 58 patients (30 women) were treated for hypothyroidism. The mortality rate was higher among women with thyroxine replacement (16.7%, 95% confidence interval [CI] 5.6 to 34.7) than those without thyroxine replacement (5.9%, 95% CI 4.1 to 8.2; p = 0.02) and no difference between men with (3.6%, 95% CI 0.1 to 17.8) and without (2.6%, 95% CI 2.0 to 3.2) thyroxine treatment (p = 0.8). Intake of diuretics (p < 0.001) was directly associated with mortality whereas intake of aspirin (p = 0.01), levothyroxine dose (p = 0.03), and serum thyroxine level (p = 0.01) were inversely associated with mortality among women on thyroxine replacement. CONCLUSIONS: Women on thyroxine replacement therapy undergoing coronary artery bypass grafting had an increased mortality rate. We speculate that insufficient thyroid hormone replacement could partly play a role in this outcome. Hypothyroidism is a common disorder affecting the cardiovascular, respiratory, hematopoietic, and renal organ systems--each of which is particularly germane in the management of the surgical patient. In general, treatment of recognized hypothyroidism is recommended before any surgical procedure whenever possible and euthyroidism should be documented by measurement of serum TSH as part of the preoperative evaluation. Such a strategy is likely to result in better surgical outcomes with improved morbidity and mortality. One exception to treating first with thyroid hormone is the patient with angina or coronary artery disease requiring bypass grafting, angioplasty or stenting. In this setting, preoperative thyroid hormone therapy could tax the ischemic myocardium. The coronary blood flow should be addressed first, and thyroid hormone therapy initiated afterwards. The authors have emphasized the need for caution in the interpretation of low serum thyroid hormones in sick or surgical patients because of the importance of distinguishing between hypothyroidism and the "euthyroid sick syndrome." There is no clear evidence at this point to support thyroid hormone replacement in the latter patients, and it may be potentially harmful. Rather, we hold that T3 treatment of various surgical and other patients with nonthyroidal illness should be deferred until proof of its therapeutic efficacy is demonstrated. OBJECTIVE: Despite improved perioperative management, atrial fibrillation (AF) after coronary artery bypass grafting (CABG) remains a relevant clinical problem, whose pathogenetic mechanisms remain incompletely explained. A reduced incidence of postoperative AF has been described in CABG patients receiving IV tri-iodothyronine (T3). This study was designed to define the role of thyroid metabolism on the genesis of postoperative AF. METHODS AND RESULTS: Free T3 (fT3), free thyroxine (fT4), and thyroid stimulating hormone were assayed at admission in 107 consecutive patients undergoing isolated CABG surgery. Patients with thyroid disease or taking drugs known to interfere with thyroid function were excluded. A preoperative rhythm other than sinus rhythm was considered an exclusion criterion. Thirty-three patients (30.8%) had postoperative AF. An older age (P=0.03), no therapy with beta-blockers (P=0.08), chronic obstructive pulmonary disease (P=0.08), lower left ventricle ejection fraction (P=0.09) and lower fT3 concentration (P=0.001), were univariate predictors of postoperative AF. On multivariate analysis, low fT3 concentration and lack of beta-blocking therapy were independently related with the development of postoperative AF (odds ratio, OR, 4.425; 95% confidence interval, CI, 1.745-11.235; P=0.001 and OR 3.107; 95% CI 1.087-8.875; P=0.03, respectively). Postoperative AF significantly prolonged postoperative hospital stay (P=0.002). CONCLUSIONS: Low basal fT3 concentration can reliably predict the occurrence of postoperative AF in CABG patients. Cardiac surgery using cardiopulmonary bypass produces a generalized systemic inflammatory response, resulting in increased postoperative morbidity and mortality. Under these circumstances, a typical pattern of thyroid abnormalities is seen in the absence of primary disease, defined as sick euthyroid syndrome (SES). The presence of postoperative SES mainly in small children and neonates exposed to long bypass times and the pharmacological profile of thyroid hormones and their effects on the cardiovascular physiology make supplementation therapy an attractive treatment option to improve postoperative morbidity and mortality. Many studies have been performed with conflicting results. In this article, we review the important literature on the development of SES in paediatric postoperative cardiac patients, analyse the existing information on thyroid hormone replacement therapy in this patient group and try to summarize the findings for a recommendation. The question addressed in this review is whether supplementation with thyroid hormones during the perioperative period improves the outcome of patients undergoing coronary artery bypass surgery. Altogether 88 relevant papers were identified using the below mentioned search, seven papers represented the best evidence to answer the question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses were tabulated. We conclude that although widespread interest has been shown on the use of thyroid hormones in the perioperative period, and the effect of cardiopulmonary bypass on thyroid hormone metabolism widely studied, there is no substantial evidence to justify routine use of thyroid hormones in patients undergoing coronary artery bypass grafting. CONTEXT: Effects of thyroid hormone therapy on postoperative morbidity and mortality in adults remain controversial. OBJECTIVE: The aim was to conduct a systematic review evaluating effects and risks of postoperative T(3) therapy in adults. DATA SOURCES: Electronic databases and reference lists through March 2010 were searched. STUDY SELECTION: Studies with comparable control groups comparing T(3) to placebo therapy in randomized controlled trials were selected. DATA EXTRACTION: Two reviewers independently screened and reviewed titles, abstracts, and articles. Data were abstracted from 14 randomized controlled trials (13 cardiac surgery and one renal transplantation). In seven studies, iv T(3) was given in high doses (0.175-0.333 μg/kg · h) for 6 to 9 h, in four studies iv T(3) was given in low doses (0.0275-0.0333 μg/kg · h for 14 to 24 h), and in three studies T(3) was given orally in variable doses and durations. DATA SYNTHESIS: Both high- and low-dose iv T(3) therapy increased cardiac index after coronary artery bypass surgery. Mortality was not significantly altered by high-dose iv T(3) therapy and could not be assessed for low-dose iv or oral T(3). Effects on systemic vascular resistance, heart rate, pulmonary capillary wedge pressure, new onset atrial fibrillation, inotrope use, serum TSH and T(4) were inconclusive. LIMITATIONS: Numbers of usable unique studies and group sizes were small. Duration of T(3) therapy was short, and dosages and routes of administration varied. CONCLUSIONS: Short duration postoperative iv T(3) therapy increases cardiac index and does not alter mortality. Effects on other parameters are inconclusive.

When is the protein NFL a biomarker?

Neurofilament light protein (NFL), may be released into the cerebrospinal fluid (CSF) during pathological processes in the central nervous system (CNS). Neurofilament light chain is a prognostic biomarker in neurological disorders such as amyotrophic lateral sclerosis, frontotemporal degeneration, axonal injury, late-onset cerebellar ataxia, multiple sclerosis and head trauma.

OBJECTIVE: To determine if CNS-derived proteins present in the CSF of multiple sclerosis (MS) patients reflect different pathologic processes of MS and if these proteins could be useful as biologic markers of disease activity. METHODS: Concentrations of the neurofilament light protein (NFL), glial fibrillary acidic protein (GFAP), S100B, and the neuron-specific enolase protein (NSE) were determined in the CSF of 66 MS patients and 50 healthy control subjects with immunoassays. RESULTS: The mean levels of the NFL were increased during all stages of MS compared with controls (p < 0.001), peaking almost 10 times higher during acute relapses. The highest levels of GFAP were found during the secondary progressive course (p < 0.001) with a strong correlation with neurologic deficits (Expanded Disability Status Scale score, r = 0.73, p < 0.001). No increase of S100B or NSE protein was found in the CSF of MS patients compared with control subjects. CONCLUSIONS: Increased level of NFL is a general feature of MS, indicating continuous axonal damage during the entire course of the disease with the most profound damage during acute relapses. GFAP may serve as a biomarker for disease progression, probably reflecting the increasing rate of astrogliosis. BACKGROUND: Loss of cortical neurons is a key pathological feature in neurodegenerative dementias. Cerebrospinal fluid (CSF) neurofilaments (Nf) are a biomarker for neuronal death and axonal loss. OBJECTIVE: To perform a meta-analysis to investigate the value of CSF Nf levels for the laboratory-supported differential diagnosis of neurodegenerative dementias. METHODS: A systematic review and meta-analysis of studies on CSF Nf heavy (NfH) and light (NfL) levels in patients with dementia. The dementia subgroups analysed were Alzheimer (AD), frontotemporal lobe dementia (FTLD), vascular dementia (SVD), minimal cognitive deficit (MCI). RESULTS: We identified 12 studies on CSF NfH and NfL levels which met the inclusion criteria and 11 were of a quality good enough to be used in this meta-analysis. CSF data was available on 818 patients (306 AD, 106 SVD, 98 FTLD, 25 MCI, 283 controls). Overall CSF NfH and NfL levels were higher in patients with AD, FTLD and SVD when compared to controls. The size of the effect ranged from 0.71 to 1.38. The strongest effect was observed for the comparison of FTLD patients with controls, both for NfL (1.38) and NfH (0.74). CSF NfL were also able to separate patients with FTLD from those with AD. CONCLUSION: At present we cannot recommend CSF NfH and NfL levels for use as a screening test in the diagnosis of dementia because of the rather small effect size. However, both neurofilament proteins may be of value for targeted investigation of some patients with FTLD, SVD and AD. In light of our previous observation of higher levels of cerebrospinal fluid (CSF) amyloid beta-42 (Abeta42) and CSF/serum albumin ratio in major depressive disorder (MDD), we analyzed two additional CSF biomarkers reflecting neurodegeneration-neurofilament protein light (NFL) and glial fibrillary acidic protein (GFAp)-in relationship to prevalent geriatric depression. Neuropsychiatric, physical, and lumbar puncture examinations, with DSM-III-R-based depression diagnoses and measurement of CSF levels of NFL and GFAp, were evaluated among a population-based sample of 78 elderly women (mean age, 73.9+/-3.2 years) without dementia for at least 10 years after CSF collection. Eleven (13.1%) women had MDD, and higher levels of NFL compared with women without depression. A multivariate model including age, NFL, Abeta42 and the CSF/serum albumin ratio showed that each biomarker was independently and positively associated with MDD, and that this biomarker profile explained more variation in the model compared with single or combined biomarkers. A CSF profile with higher levels of NFL, Abeta42, and CSF/serum albumin ratio may indicate neuropathological and vascular events in depression etiology. This contrasts with the well-characterized pattern of low Abeta42, higher CSF/serum albumin ratio, and higher NFL in Alzheimer's disease. BACKGROUND: Sports-related head trauma is common but still there is no established laboratory test used in the diagnostics of minimal or mild traumatic brain injuries. Further the effects of recurrent head trauma on brain injury markers are unknown. The purpose of this study was to investigate the relationship between Olympic (amateur) boxing and cerebrospinal fluid (CSF) brain injury biomarkers. METHODS: The study was designed as a prospective cohort study. Thirty Olympic boxers with a minimum of 45 bouts and 25 non-boxing matched controls were included in the study. CSF samples were collected by lumbar puncture 1-6 days after a bout and after a rest period for at least 14 days. The controls were tested once. Biomarkers for acute and chronic brain injury were analysed. RESULTS: NFL (mean ± SD, 532±553 vs 135±51 ng/L p = 0.001), GFAP (496±238 vs 247±147 ng/L p<0.001), T-tau (58±26 vs 49±21 ng/L p<0.025) and S-100B (0.76±0.29 vs 0.60±0.23 ng/L p = 0.03) concentrations were significantly increased after boxing compared to controls. NFL (402±434 ng/L p = 0.004) and GFAP (369±113 ng/L p = 0.001) concentrations remained elevated after the rest period. CONCLUSION: Increased CSF levels of T-tau, NFL, GFAP, and S-100B in >80% of the boxers demonstrate that both the acute and the cumulative effect of head trauma in Olympic boxing may induce CSF biomarker changes that suggest minor central nervous injuries. The lack of normalization of NFL and GFAP after the rest period in a subgroup of boxers may indicate ongoing degeneration. The recurrent head trauma in boxing may be associated with increased risk of chronic traumatic brain injury. BACKGROUND: There is a lack of reliable biomarkers of axonal degeneration. Neurofilaments are promising candidates to fulfil this task. We compared two highly sensitive assays to measure two subunits of the neurofilament protein (neurofilament light (NfL) and neurofilament heavy chain (NfH)). METHODS: We evaluated the analytical and clinical performance of the UmanDiagnostics NF-light(®) enzyme-linked immunosorbent assay (ELISA) in the cerebrospinal fluid (CSF) of a group of 148 patients with clinically isolated syndrome (CIS) or multiple sclerosis (MS), and 72 controls. We compared our results with referring levels of our previously-developed CSF NfH(SMI35) assay. RESULTS: Exposure to room temperature (up to 8 days) or repetitive thawing (up to 4 thaws) did not influence measurement of NfL concentrations. Values of NfL were higher in all disease stages of CIS/MS, in comparison to controls (p ≤ 0.001). NfL levels correlated with the Expanded Disability Status Scale (EDSS) score in patients with relapsing disease (r(s) = 0.31; p = 0.002), spinal cord relapses and with CSF markers of acute inflammation. The ability of NfL to distinguish patients from controls was greater than that of NfH(SMI35) in both CIS patients (p = 0.001) and all MS stages grouped together (p = 0.035). CONCLUSIONS: NfL proved to be a stable protein, an important prerequisite for a reliable biomarker, and the NF-light(®) ELISA performed better in discriminating patients from controls, compared with the ECL-NfH(SMI35) immunoassay. We confirmed and expanded upon previous findings regarding neurofilaments as quantitative markers of neurodegeneration. Our results further support the role of neurofilaments as a potential surrogate measure for neuroprotective treatment in MS studies. BACKGROUND: Neurofilaments are promising biomarkers in multiple sclerosis (MS) and increased levels in cerebrospinal fluid (CSF) indicate axonal damage or degeneration. In a previous study, neurofilament light chain (NfL) levels in CSF of relapsing remitting (RR) patients with MS were normalized by natalizumab treatment. AIMS OF THE STUDY: We compared the coherence between NfL and neurofilament heavy chain (NfH(SMI) (35) ) levels in longitudinal CSF samples in a subset of these patients. METHODS: In 30 patients with RRMS, CSF was obtained prior to and following 12 months of natalizumab treatment. NfH(SMI) (35) was measured by an electrochemiluminescence-based immunoassay. NfL levels were determined previously by the UmanDiagnostics NF-light(®) assay. RESULTS: NfH(SMI) (35) decreased in 73.3% and NfL in 90% of the patients following natalizumab treatment (32.4 vs 27.4 pg/ml, P = 0.002 and 820 vs 375 pg/ml, P < 0.0001). Patients experiencing a relapse showed higher NfH(SMI) (35) levels compared with patients in remission (47.7 vs 27.6 pg/ml, n = 8, P = 0.001). This difference was less obvious for NfL (1055 vs 725 pg/ml, P = 0.256). In patients in remission, NfL levels were lower following natalizumab treatment (830 vs 365 pg/ml, n = 20, P = 0.0002), whereas the same comparison failed significance for NfH(SMI) (35) (28.3 vs 26.9 pg/ml, P = 0.086). CONCLUSIONS: We confirm previous findings, indicating reduced axonal damage under natalizumab treatment by measuring NfH(SMI) (35) , using an assay with independent methodology. In comparison with NfH(SMI) (35) , NfL changes were more pronounced and the treatment effect also included patients in remission. Our results suggest that NfL is superior over NfH(SMI) (35) as therapeutic biomarker and is a promising candidate to measure neuroaxonal damage in MS treatment trials. Conflict of interest statement: Competing Interests: J. Gaiottino reports no disclosures; N. Norgren is employed by UmanDiagnostics AB, Sweden; R. Dobson, J. Topping, A. Nissim, A. Malsapina, J.P. Bestwick, A.U. Monsch, A. Regeniter report no disclosures; R.L. Lindberg has received research support from the Swiss MS Society, Swiss National Science Foundation, European FP6 and IMI JU programs, Roche Postdoc Fellowship Program (RPF-program), unrestricted research grants from Novartis and Biogen. L. Kappos reports, the University Hospital Basel as employer of Dr. Kappos has received and dedicated to research support fees for board membership, consultancy or speaking, or grants, in the last 3 years from Actelion, Advancell, Allozyne, Bayer, Bayhill, Biogen Idec, BioMarin, CSL Behring, Eli Lilly, European Union, GeNeuro, Genmab, Gianni Rubatto Foundation, Glenmark, Merck Serono, MediciNova, Mitsubishi Pharma, Novartis, Novartis Research Foundation, Novonordisk, Peptimmune, Roche, Roche Research Foundation, Sanofi-Aventis, Santhera, Swiss MS Society, Swiss National Research Foundation, Teva, UCB, and Wyeth. D. Leppert is an employee of F. Hoffmann-La Roche Ltd. A. Petzold reports no disclosure. G. Giovannoni has received research grant support from Bayer–Schering Healthcare, Biogen–Idec, GW Pharma, Merck Serono, Merz, Novartis, Teva and Sanofi–Aventis. He has received personal compensation for participating on Advisory Boards in relation to clinical trial design, trial steering committees and data and safety monitoring committees from: Bayer–Schering Healthcare, Biogen–Idec, Eisai, Elan, Fiveprime, Genzyme, Genentech, GSK, Ironwood, Merck–Serono, Novartis, Pfizer, Roche, Sanofi–Aventis, Synthon BV, Teva, UCB Pharma and Vertex Pharmaceuticals. J. Kuhle has received research support from the Swiss MS Society, Swiss ALS Society, Protagen AG, Roche and Novartis and served in scientific advisory boards for Genzyme/Sanofi-Aventis, Merck Serono and Novartis Pharma. His work is supported by an ECTRIMS Research Fellowship Programme and by the “Forschungsfonds” of the University of Basel, Switzerland. This does not alter the authors' adherence to all the PLOS ONE policies on sharing data and materials. BACKGROUND: Prevalence of neurocognitive impairment in HIV-1 infected patients is reported to be high. Whether this is a result of active HIV-related neurodegeneration is unclear. We examined axonal injury in HIV-1 patients by measuring the light subunit of neurofilament protein (NFL) in CSF with a novel, sensitive method. METHODS: With a cross-sectional design, CSF concentrations of neurofilament protein light (NFL) (marker of neuronal injury), neopterin (intrathecal immunoactivation) and CSF/Plasma albumin ratio (blood-brain barrier integrity) were analyzed on CSF from 252 HIV-infected patients, subdivided into untreated neuroasymptomatics (n = 200), HIV-associated dementia (HAD) (n = 14) and on combinations antiretroviral treatment (cART) (n = 85), and healthy controls (n = 204). 46 HIV-infected patients were included in both treated and untreated groups, but sampled at different timepoints. Furthermore, 78 neuroasymptomatic patients were analyzed before and after treatment initiation. RESULTS: While HAD patients had the highest NFL concentrations, elevated CSF NFL was also found in 33% of untreated neuroasymptomatic patients, mainly in those with blood CD4+ cell counts below 250 cells/μL. CSF NFL concentrations in the untreated neuroasymptomatics and treated groups were equivalent to controls 18.5 and 3.9 years older, respectively. Neopterin correlated with NFL levels in untreated groups while the albumin ratio correlated with NFL in both untreated and treated groups. CONCLUSIONS: Increased CSF NFL indicates ongoing axonal injury in many neuroasymptomatic patients. Treatment decreases NFL, but treated patients retain higher levels than controls, indicating either continued virus-related injury or an aging-like effect of HIV infection. NFL correlates with neopterin and albumin ratio, suggesting an association between axonal injury, neuroinflammation and blood-brain barrier permeability. NFL appears to be a sensitive biomarker of subclinical and clinical brain injury in HIV and warrants further assessment for broader clinical use. OBJECTIVES: Magnetic resoce imaging (MRI) of the brain and spinal cord is the gold standard for assessing disease activity in multiple sclerosis (MS). MRI is an excellent instrument for determination of accumulated damage to the brain and spinal cord, but tells us little about ongoing tissue damage. In this study, biomarkers of oligodendrocyte, axonal and astrocyte injury were related to MRI and clinical findings and used to assess tissue damage in MS. MATERIALS AND METHODS: Cerebrospinal fluid from 44 patients with relapsing-remitting MS, 20 with secondary progressive MS and 15 controls were investigated with ELISA to determine levels of myelin basic protein (MBP), neurofilament light (NFL) and glial fibrillary acidic protein (GFAp). Patients underwent MRI of the brain and spinal cord, and gadolinium enhancing lesions, T1 lesions and T2 lesions were counted. RESULTS: Patients in clinical relapse and patients with nonsymptomatic gadolinium enhancing lesions had high levels of MBP and NFL, indicating ongoing damage to oligodendrocytes and axons. The level of MBP dropped quickly within a week from the onset of a relapse, whereas NFL remained elevated for several weeks and GFAp slowly rose during the course of a relapse. Relapsing-remitting MS patients without gadolinium enhancing lesions had values of MBP, NFL and GFAp similar to controls, while patients with secondary progressive disease had moderately increased values of all biomarkers. CONCLUSIONS: Analysis of MBP, NFL and GFAp provides direct means to measure tissue damage and is a useful addition to our methods for evaluation of MS. BACKGROUND: Neurofilaments (Nf) are major structural proteins that occur exclusively in neurons. In spinal cord injury (SCI), the severity of disease is quantified by clinical measures that have limited sensitivity and reliability, and no blood-based biomarker has been established to further stratify the degree of injury. We aimed to examine a serum-based NfL immunoassay as predictor of the clinical outcome in SCI. METHODS: Longitudinal measurement of serum NfL was performed in patients with central cord syndrome (CCS, n=4), motor-incomplete SCI (iSCI, n=10), motor-complete SCI (cSCI, n=13) and healthy controls (HC, n=67), and correlated with clinical severity, neurological outcome, and neuroprotective effect of the drug minocycline. RESULTS: Baseline NfL levels were higher in iSCI (21 pg/mL) and cSCI (70 pg/mL) than in HC (5 pg/mL, p=0.006 and p<0.001) and CCS (6 pg/mL, p=0.025 and p=0.010). Levels increased over time (p<0.001) and remained higher in cSCI versus iSCI (p=0.011) and than in CCS (p<0.001). NfL levels correlated with American Spinal Injury Association (ASIA) motor score at baseline (r=-0.53, p=0.004) and after 24 h (r=-0.69, p<0.001) and 3-12-month motor outcome (baseline NfL: r=-0.43, p=0.026 and 24 h NfL: r=-0.72, p<0.001). Minocycline treatment showed decreased NfL levels in the subgroup of cSCI patients. CONCLUSIONS: Serum NfL concentrations in SCI patients show a close correlation with acute severity and neurological outcome. Our data provide evidence that serum NfL is of prognostic value in SCI patients for the first time. Further, blood NfL levels may qualify as drug response markers in SCI. BACKGROUND: Mild traumatic brain injury (TBI) or concussion is common in many sports. Today, neuropsychological evaluation is recommended in the monitoring of a concussion and in return-to-play considerations. To investigate the sensitivity of neuropsychological assessment, we tested amateur boxers post bout and compared with controls. Further the relationship between neuropsychological test results and brain injury biomarkers in the cerebrospinal fluid (CSF) were investigated. METHOD: Thirty amateur boxers on high elite level with a minimum of 45 bouts and 25 non-boxing matched controls were included. Memory tests (Rey Osterrieth Complex Figure, Listening Span, Digit Span, Controlled Word Association Test, and computerized testing of episodic memory), tests of processing speed and executive functions (Trail Making, Reaction Time, and Finger Tapping) were performed and related to previously published CSF biomarker results for the axonal injury marker neurofilament light (NFL). RESULTS: The neurological assessment showed no significant differences between boxers and controls, although elevated CSF NFL, as a sign of axonal injury, was detected in about 80% of the boxers 1-6 days post bout. The investigation of the relationship between neuropsychological evaluation and CSF NFL concentrations revealed that boxers with persisting NFL concentration elevation after at least 14 days resting time post bout, had a significantly poorer performance on Trail Making A (p = 0.041) and Simple Reaction Time (p = 0.042) compared to other boxers. CONCLUSION: This is the first study showing traumatic axonal brain injury can be present without measureable cognitive impairment. The repetitive, subconcussive head trauma in amateur boxing causes axonal injury that can be detected with analysis of CSF NFL, but is not sufficient to produce impairment in memory tests, tests of processing speed, or executive functions. The association of prolonged CSF NFL increase in boxers with impairment of processing speed is an interesting observation, which needs to be verified in larger studies. OBJECT: In previous studies of traumatic brain injury (TBI), neural biomarkers of injury correlate with injury severity and predict neurological outcome. The object of this paper was to characterize neurofilament-H (NFL-H) as a predictor of injury severity in patients who have suffered mild TBI (mTBI). Thus, the authors hypothesized that phosphorylated NFL-H (pNFL-H) levels are higher in mTBI patients than in healthy controls and identify which subjects experienced a more severe injury such as skull fractures, intracranial hemorrhaging, and/or contusions as detected by CT scans. METHODS: In this prospective clinical study, blood (8 ml) was collected from subjects (n = 34) suffering from mTBI (as defined by the American Congress of Rehabilitation and Glasgow Coma Scale scores between 13 and 15) at Parkland Hospital, Dallas, Texas, on Days 1 and 3 after injury). Additional clinical findings from the CT scans were also used to categorize the TBI patients into those with and those without clinical findings on the scans (CT+ and CTgroups, respectively). The serum levels of pNFL-H were measured using the enzyme-linked immunosorbent assay. RESULTS: Compared with healthy controls, the mTBI patients exhibited a significant increase in the serum levels of pNFL-H on Days 1 (p = 0.00001) and 3 (p = 0.0001) after TBI. An inverse correlation was observed between pNFL-H serum levels and Glasgow Coma Scale scores, which was significant. Additionally, using receiver operating characteristic curve analysis to compare the mTBI cases with controls to determine sensitivity and specificity, an area under the curve of 100% was achieved for both (p = 0.0001 for both). pNFL-H serum levels were only significantly higher on Day 1 in mTBI patients in the CT+ group (p < 0.008) compared with the CT- group. The area under the curve (82.5%) for the CT+ group versus the CT- group was significant (p = 0.021) with a sensitivity of 87.5% and a specificity of 70%, using a cutoff of 1071 pg/ml of pNFL-H in serum. CONCLUSIONS: This study describes the serum profile of pNFL-H in patients suffering from mTBI with and without CT findings on Days 1 and 3 after injury. These results suggest that detection of pNFL-H may be useful in determining which individuals require CT imaging to assess the severity of their injury. OBJECTIVE: Diffusion tensor imaging (DTI) is sensitive to white matter tract pathology. A core signature involving the corticospinal tracts (CSTs) has been identified in amyotrophic lateral sclerosis (ALS). Raised neurofilament light chain protein (NfL) in cerebrospinal fluid (CSF) is thought to reflect axonal damage in a range of neurological disorders. The relationship between these two measures was explored. METHODS: CSF and serum NfL concentrations and DTI acquired at 3 Tesla on the same day were obtained from ALS patients (n = 25 CSF, 40 serum) and healthy, age-similar controls (n = 17 CSF, 25 serum). Within-group correlations between NfL and DTI measures of microstructural integrity in major white matter tracts (CSTs, superior longitudinal fasciculi [SLF], and corpus callosum) were performed using tract-based spatial statistics. RESULTS: NfL levels were higher in patients compared to controls. CSF levels correlated with clinical upper motor neuron burden and rate of disease progression. Higher NfL levels were significantly associated with lower DTI fractional anisotropy and increased radial diffusivity in the CSTs of ALS patients, but not in controls. INTERPRETATION: Elevated CSF and serum NfL is, in part, a result of CST degeneration in ALS. This highlights the wider potential for combining neurochemical and neuroimaging-based biomarkers in neurological disease.

Is protein CXCR4 used as a prognostic marker of cancer?

Yes, the chemokine C-X-C motif receptor 4 (CXCR4) has been found to be a prognostic marker in various types of cancer.

INTRODUCTION: Sentinel lymph node (SLN) biopsy is an important independent prognostic factor for invasive cutaneuos melanoma, although its role is strongly debated. In clinical practice SLN leads to complete lymph node dissection of basin draining melanoma site. However only 7-30% of positive sentinel node patients present additional non SLN metastasis. Melanoma cells diffusion through SLN and extranodal spreading depends upon biological features, such as cell chemokine receptors and adhesion molecules. CXCR4 has been proposed in melanoma patients as prognostic marker. Therefore we have analyzed both histopathological parameters and CXCR4 expression in melanoma infiltrate of SLN, in order to evaluate its potential prognostic role. RESULTS: Micrometastases were detected in 23 cases (48.93%); metastases >2 mm in 23 cases (48.93%) and isolated metastatic cells in one case (2.01%). High CXCR4 expression was observed in 21 nodal metastases. Node metastases in complete dissection were associated to >10% relative tumor area (RTA) in all lymph nodes (p = 0.006). Extranodal invasion (p = 0.006) and >2 mm centripetal metastasis thickness (p = 0.01), while shorter Disease Free Survival (DFS) was significantly associated to high CXCR4 expression (p = 0.02). MATERIALS AND METHODS: Forty-seven positive lymph node metastases were collected and analysed for both histopathological parameters and CXCR4 expression. CONCLUSION: More than 10% RTA in SLN, extranodal invasion and centripetal metastasis thickness all predict additional lymph node metastases in melanoma site draining basins. Moreover, high CXCR4 expression is correlated to shorter DFS and could be used as a prognostic marker in order to stratify melanoma patients at higher progression risk. The molecular basis of sarcoma remains poorly understood. However, recent studies have begun to uncover some of the molecular pathways involved in sarcomagenesis. The chemokine receptor CXCR4 has been implicated in sarcoma development and has been found to be a prognostic marker for poor clinical outcome. There is growing evidence that overexpression of CXCR4 plays a significant role in development of metastatic disease, especially in directing tumor cells towards the preferential sites of metastases in sarcoma, lung and bone. Although further investigation is necessary to validate these pathways, there is potential for clinical application, particularly in the use of pharmacologic inhibitors of CXCR4 as means of preventing sarcoma metastasis. Interaction between CXCR4 and CXCL12 plays a role in tumor progression. The present study examined CXCR4, CXCL12 and CD133 expression in liver metastases of colorectal cancer (CLM) and determined whether the expression profiles affect the tumor microenvironment and thus progression, and whether they could serve as a prognostic marker for survival. Liver metastases of colorectal cancer collected from 92 patients were evaluated by CXCR4, CXCL12 and CD133 immunohistochemistry and clinicopathological data were analyzed. The expression profile of CXCR4 was determined in the colorectal cancer cell line, SW48. The expression of cytoplasmic CXCR4 was higher in 36 (39%) patients than that indicated by CXCR4 staining intensity of hepatocytes. High levels of nuclear CXCR4 expression in 23 (25%) patients significantly correlated with CXCL12 expression in hepatocytes. Nuclear CXCR4 expression was increased in the cancer cells after exposure to CXCL12. Univariate and multivariate analyses demonstrated that the high levels of nuclear CXCR4 and CXCL12 expression in hepatocytes were significantly better prognostic factors for overall and hepatic disease-free survival in patients with CLM. The expression of CXCR4 and CXCL12 in CLM may have an interactive effect that could alter the tumor microenvironment. CXCR4 expression in metastatic liver tumors together with the upregulation of CXCL12 in hepatocytes may help to predict the clinical outcomes of patients with CLM after hepatectomy. BACKGROUND: Node-positive breast cancer patients are a high-risk group. However, not all such patients will succumb to the disease. The molecular basis for this biologic heterogeneity is poorly understood. The chemokine receptor CXCR4 is a marker of metastatic disease. Its prognostic role in node-positive patients is unknown. We postulate that high CXCR4 overexpression in node-positive breast cancer specimens predicts a poor outcome. METHODS: 185 node-positive breast cancer patients were evaluated. All had standardized treatment and surveillance protocols. CXCR4 levels were detected with Western blots. Results were quantified against 1 µg of HeLa cells. CXCR4 expression was defined as high (≥ 7.5-fold) or low (<7.5-fold). Primary endpoints were cancer recurrence and death. Statistical analyses were Kaplan-Meier curves, log-rank test, and Cox proportional hazard model, with a P-value of ≤ 0.05 as significant. RESULTS: The mean follow-up time was 54 months; 148 patients (80%) had low CXCR4 and 37 patients (20%) had high CXCR4 level. The 5-year overall survival (OS) for the low and high CXCR4 group was 69% and 57%, respectively (P=0.02). The 5-year disease-free survival (DFS) for the low and high CXCR4 group was 62% and 53%, respectively (P=0.08). On multivariate analysis, T stage (P=0.001) and grade (P=0.04) were independent predictors of DFS, while T stage (P=0.005), grade (P=0.024), and CXCR4 level (P=0.01) were independent predictors of OS. CONCLUSION: High CXCR4 level in cancer specimens independently predicts a poor outcome for patients with node-positive breast cancer. PURPOSE: CXCR4 has been identified as a prognostic marker for acute myeloid leukemia (AML) and other maligcies. We describe the development and characterization of a fully human antibody to CXCR4 and its application for therapy of AML, non-Hodgkin lymphoma (NHL), chronic lymphoid leukemia (CLL), and multiple myeloma. EXPERIMENTAL DESIGN: Human transgenic mice were immunized with CXCR4-expressing cells, and antibodies reactive with CXCR4 were analyzed for apoptosis induction and ability to interfere with CXCL12-induced migration and calcium flux. In vivo efficacy was determined in multiple AML, NHL, and multiple myeloma xenograft tumors in severe combined immunodeficient mice. RESULTS: BMS-936564/MDX-1338 is a fully human IgG(4) monoclonal antibody that specifically recognizes human CXCR4. In vitro studies show that MDX-1338 binds to CXCR4-expressing cells with low omolar affinity, blocks CXCL12 binding to CXCR4-expressing cells, and inhibits CXCL12-induced migration and calcium flux with low omolar EC(50) values. When given as monotherapy, MDX-1338 exhibits antitumor activity in established tumors including AML, NHL, and multiple myeloma xenograft models. In addition, we show that MDX-1338 induced apoptosis on a panel of cell lines and propose that antibody-induced apoptosis is one of the mechanisms of tumor growth inhibition. CONCLUSIONS: BMS-936564/MDX-1338 is a potent CXCR4 antagonist which is efficacious as monotherapy in tumor-bearing mice and is currently in phase I for the treatment of relapsed/refractory AML, NHL, CLL, and multiple myeloma. Breast cancer is one of the leading causes of cancer related deaths worldwide. Breast cancer-related mortality is associated with the development of metastatic potential of primary tumor lesions. The chemokine receptor CXCR4 has been found to be a prognostic marker in various types of cancer, including breast cancer. Recent advances in the field of cancer biology has pointed to the critical role that CXCR4 receptor and its ligand CXCL12 play in the metastasis of various types of cancer, including breast cancer. Breast tumors preferentially metastasize to the lung, bones and lymph nodes, all of which represent organs that secrete high levels of CXCL12. CXCL12 acts as a chemoattractant that drives CXCR4-positive primary tumor cells towards secondary metastatic sites leading to the onset of metastatic lesions. Since its discovery in 2001, the CXCR4 field has progressed at a very fast rate and further studies have pointed to the role of CXCR4 in dissemination of tumor cells from primary sites, transendothelial migration of tumor cells as well as the trafficking and homing of cancer stem cells. This review summarizes the information that has been obtained over the years regarding the role of CXCL12-CXCR4 signaling in breast cancer, discusses its potential application to the development of new therapeutic tools for breast cancer control, and elucidates the potential therapeutic challenges which lie ahead and the future directions that this field can take for the improvement of prognosis in breast cancer patients. The G-protein-coupled receptor, CXCR4, is highly expressed on a number of cell types, and together with its ligand, CXCL12, plays an important role in immune development and trafficking of cells. CXCR4 promotes tumor growth, angiogenesis and metastasis, and is a prognostic marker in a number of different types of tumors. Additionally, CXCR4 is utilized, together with CD4, for entry of T-tropic HIV viruses. Ethnic differences in incidence and mortality of various cancers, and in the response to highly active antiretroviral treatment (HAART) of HIV-1 infected individuals have been reported. The aim of this study was to establish if differences in the CXCR4-CXCL12 axis exist between ethnically divergent uninfected South Africans. CXCR4 density was significantly higher on CD4(+) and CD8(+) T cells, B cells and CD56(dim) NK cells, and CXCL12 levels lower in Black compared with Caucasian individuals. Furthermore, an inverse correlation was observed between CXCR4 density on CD56(+) and CD3(+) cells and age, only in Black individuals. CXCL12-3'A heterozygosity (AG) found in 28% of Caucasians did not explain the higher plasma levels of CXCL12 compared to Black individuals who were all GG genotypes, suggesting that other factors influence homeostatic levels of CXCL12. In conclusion, this study demonstrates that ethnically divergent populations show clear differences in both CXCR4 density and CXCL12 plasma levels which may influence the course of cancer and HIV-1 infection. Pancreatic ductal adenocarcinoma (PDAC) remains a major unsolved health problem. As conventional treatments have shown only a modest impact on disease course, development of new therapeutic strategies based on the molecular biology of PDAC must be a high priority. The identification of relevant predictive and prognostic biomarkers which can be used to select patient subgroups that may benefit from conventional treatments and new targeted agents will be of considerable interest. We have demonstrated the ability of the metabolizing gemcitabine protein (the human Equilibrative nucleoside transporter 1 and the deoxycytidine kinase) in predicting the benefit of adjuvant gemcitabine-based therapy in resected PDAC patients. Beside these predictive biomarkers, we have evaluated different molecular factors that may impact on the likely course of this cancer. The chemokine receptor CXCR4 that has been shown to be implicated in PDAC tumorigenicity and aggressiveness could serve as a prognostic marker for survival after a curative-intent surgery and was associated with the pattern of tumour recurrence (distant versus local relapse). Our findings were validated in an independent cohort of patients. Overall our results suggested that (i) the benefit of an adjuvant gemcitabine-based therapy can be predicted based on the tumour expression of hENT1 and dCK, (ii) CXCR4 is an independent negative prognostic factor and an independent predictor of distant relapse suggesting that anti-CXCR4 targeting therapies can be a promising treatment in combination with cytotoxic chemotherapy in the adjuvant setting. These data open new perspectives for designing trials based on a molecular driven strategy. Aberrant chemokine (C-X-C motif) receptor CXCR4 expressions in maligt tissues have been reported, but its role in gastric cancer prognosis remains unknown. Our studies were designed to investigate the expression and prognostic significance of CXCR4 in patients with gastric cancer. CXCR4 expression was retrospectively analyzed by immunohistochemistry in 97 patients with gastric adenocarcinoma from China. Results were assessed for association with clinical features and overall survival by using Kaplan-Meier analysis. Prognostic values of CXCR4 expression and clinical outcomes were evaluated by Cox regression analysis. A molecular prognostic stratification scheme incorporating CXCR4 expression was determined by using receiver operating characteristic (ROC) analysis. The results show that CXCR4 predomitly localized in the cell membranes and cytoplasm. The protein level of CXCR4 was upregulation in gastric cancer tissues and upregulated expression of CXCR4 was only significantly associated with Lauren classification (P<0.001). Increased CXCR4 expression in gastric cancer tissues was positively correlated with poor overall survival of gastric cancer patients (P<0.001). Further multivariate Cox regression analysis suggested that intratumoral CXCR4 expression was an independent prognostic indicator for the disease. Applying the prognostic value of intratumoral CXCR4 density to TNM stage system showed a better prognostic value in patients with gastric cancer. In conclusion, intratumoral CXCR4 expression was recognized as an independent prognostic marker for the overall survival of patients with gastric cancer. On the basis of TNM stage, detection of CXCR4 expression will be helpful for predicting prognosis for patients with gastric cancer. PURPOSE: Radioresistance of cancer cells remains a fundamental barrier for maximum efficient radiotherapy. Tumor heterogeneity and the existence of distinct cell subpopulations exhibiting different genotypes and biological behaviors raise difficulties to eradicate all tumorigenic cells. Recent evidence indicates that a distinct population of tumor cells, called cancer stem cells (CSC), is involved in tumor initiation and recurrence and is a putative cause of tumor radioresistance. There is an urgent need to identify the intrinsic molecular mechanisms regulating the generation and maintece of resistance to radiotherapy, especially within the CSC subset. The chemokine C-X-C motif receptor 4 (CXCR4) has been found to be a prognostic marker in various types of cancer, being involved in chemotaxis, stemness and drug resistance. The interaction of CXCR4 with its ligand, the chemokine C-X-C motif ligand 12 (CXCL12), plays an important role in modulating the tumor microenvironment, angiogenesis and CSC niche. Moreover, the therapeutic inhibition of the CXCR4/CXCL12 signaling pathway is sensitizing the maligt cells to conventional anti-cancer therapy. CONTENT: Within this review we are summarizing the role of the CXCR4/CXCL12 axis in the modulation of CSC properties, the regulation of the tumor microenvironment in response to irradiation, therapy resistance and tumor relapse. CONCLUSION: In light of recent findings, the inhibition of the CXCR4/CXCL12 signaling pathway is a promising therapeutic option to refine radiotherapy. PURPOSE: The prognostic value of aberrant C-X-C chemokine receptor type 4 (CXCR4) levels in NSCLC has been described in empirical studies. This meta-analysis evaluates the value of CXCR4 as a prognostic marker for NSCLC and determines the relationship between CXCR4 and clinicopathological features of NSCLC. METHODS: A comprehensive search of the English-language literature in PubMed, Embase, Google Scholar and Web of Science was performed. Articles containing sufficient published data to determine an estimate of the hazard ratio (HR) and a 95% confidence interval (95% CI) for over survival (OS) or disease-free survival (DFS) were selected. Of 417 potentially relevant studies, 10 eligible studies (1,334 NSCLC patients) met the inclusion criteria. RESULTS: Overall, high CXCR4 expression was significantly associated with a poor OS rate (HR=1.59, 95% CI=1.36-1.87, P<0.001) while the association with DFS was not statistically significant (HR=1.00, 95% CI=0.37-2.69, P=0.993). Stratified analysis by subcellular localization found that CXCR4 overexpression in the non-nucleus predicts poor OS (HR=1.65, 95% CI=1.40-1.95, P<0.001) and DFS (HR=3.06, 95% CI=2.15-4.37, P<0.001), but elevated CXCR4 expression in the nucleus was positively associated with DFS (HR=0.44, 95% CI=0.26-0.75, P=0.002). NSCLC patients with CXCR4 expression were more likely to be diagnosed with adenocarcinoma cancer (OR=1.45, 95% CI=1.07-1.95, P=0.016), lymph node involvement (OR=0.69, 95% CI=0.50-0.96, P=0.027), and distant metastasis (OR=0.36, 95% CI=0.14-0.93, P=0.035). CONCLUSION: Aberrant overexpression of CXCR4 is associated with worse overall survival, adenocarcinoma histology, distant metastasis, lymph node involvement in NSCLC.

How does thyroid hormone regulate SR-Ca2+ ATPase (SERCA) protein in the heart?

The thyroid hormone (TH) induced regulation of SERCA is mediated both by non-genomic and genomic actions. Genomic actions are mediated by the binding of T(3) receptors (TRs) to the thyroid response elements in the SERCA promotor and result in increased gene expression. Thyroid hormone increases the transcription of SERCA 2 through three thyroid hormone response elements. Data show that the regulation of cardiac SERCA by thyroid hormone is made at the pretranslational and possibly transcriptional level TRβ1 is shown to be coupled to the expression of SERCA in the heart An increase of TR expression in the hypertrophied heart has been show to result in increased SERCA expression. Inhibition of TRα1 by dronedarone does not change the expression of SERCA in the heart Findings show that SERCA 2 gene expression is regulated by TR isoform-specific interactions with transcription factor (MEF-2) Hypothyroidism is accompanied by decreased expression of SERCA in the heart. T3 increases expression of the cardiac SERCA TH treatment can reverse the reduction in the ratio of SERCA to phospholamban expression which is found in postinfarcted hearts TH treatment results in increased expression of SERCA in hearts from banded rats

Age-associated slowing of cardiac relaxation related to the decline in the Ca2+ pump function of cardiac sarcoplasmic reticulum (SR) has been previously described. It is unclear if the decreased Ca2+ pump function results from a lower amount of Ca2(+)-ATPase protein or a decreased pumping activity of the enzyme. To determine if these alterations could be mediated by changes in the amount of the protein itself, the level of the messenger RNA (mRNA) coding for the Ca2(+)-ATPase of the SR of Fischer rat hearts (4- and 30-month-old rats) were quantitated with a Northern blotting technique. We observed that the levels of SR Ca2(+)-ATPase mRNA were 60% lower in old rats as compared with young rats, suggesting that a quantitative reduction in the levels of the corresponding protein could occur during aging to explain the delayed diastolic relaxation documented in old animals as opposed to a change in the specific activity of this enzyme. The thyroid hormone responsiveness of SR Ca2(+)-ATPase mRNA has been previously established. We have found in this study that the thyroxine levels were consistently lower in old rats; however, this difference was relatively small (4.3 +/- 0.7 and 3.1 +/- 0.8 micrograms/dl [mean +/- SD), respectively, in young and old rats). In addition, no age-induced decrease in 3,5,3'-triiodothyronine levels was observed, suggesting that the aging process itself may be responsible for the changes in SR Ca2(+)-ATPase mRNA levels. Thyroid hormone (T3) increases the transcription of the sarcoplasmic reticulum Ca2+ adenosine triphosphatase (ATPase) gene (SERCA 2) through three thyroid hormone response elements. The existence of repetitive cis elements with different configurations is likely to serve specific functions such as interactions with nuclear transcription factors. In addition, the presence of different T3 receptor isoforms (T3Rs) may contribute to another level of complexity in providing specificity for T3 action. In this study, we investigated T3R alpha 1-vs. T3R beta 1-specific interactions with the myocyte enhancer-specific factor-2 (MEF-2) on the expression of the SERCA 2 gene in transient transfection assays in embryonal heart-derived H9c2 cells. MEF-2a in combination with either T3R alpha 1 or T3R beta 1 isoforms resulted in a 2.5-fold increase in SERCA 2 transgene expression in the absence of T3. Addition of T3 did not induce any further increase in SERCA 2 expression when T3R alpha 1 and MEF-2a expression vectors were cotransfected. In contrast, in the presence of T3R beta 1 and MEF-2, the addition of T3 increased chlorampenicol acetyltransferase activity by an additional 2.2-fold to a total 5.5-fold increase. The interaction between MEF-2a and T3R is transcription factor specific because another factor that binds to MEF-2 consensus sites (heart factor 1b) was not able to interact with T3R. In addition, MEF-2a failed to interact with other nuclear factors (cAMP response element-binding protein and Egr-1) that stimulate SERCA 2 gene transcription. In addition, we found that a single homologous thyroid hormone response element is not able to mediate the interactions between MEF-2a and T3Rs to increase SERCA 2 gene transcription. Our findings point to T3R isoform-specific interactions with a cell type-specific transcription factor (MEF-2) in the regulation of SERCA 2 gene expression. We asked whether thyroid hormone (T4) would improve heart function in left ventricular hypertrophy (LVH) induced by pressure overload (aortic banding). After banding for 10-22 wk, rats were treated with T4 or saline for 10-14 d. Isovolumic LV pressure and cytosolic [Ca2+] (indo-1) were assessed in perfused hearts. Sarcoplasmic reticulum Ca2+-ATPase (SERCA), phospholamban, and alpha- and beta-myosin heavy chain (MHC) proteins were assayed in homogenates of myocytes isolated from the same hearts. Of 14 banded hearts treated with saline, 8 had compensated LVH with normal function (LVHcomp), whereas 6 had abnormal contraction, relaxation, and calcium handling (LVHdecomp). In contrast, banded animals treated with T4 had no myocardial dysfunction; these hearts had increased contractility, and faster relaxation and cytosolic [Ca2+] decline compared with LVHcomp and LVHdecomp. Myocytes from banded hearts treated with T4 were hypertrophied but had increased concentrations of alpha-MHC and SERCA proteins, similar to physiological hypertrophy induced by exercise. Thus thyroid hormone improves LV function and calcium handling in pressure overload hypertrophy, and these beneficial effects are related to changes in myocyte gene expression. Induction of physiological hypertrophy by thyroid hormone-like signaling might be a therapeutic strategy for treating cardiac dysfunction in pathological hypertrophy and heart failure. Type 2 iodothyronine deiodinase (D(2)) catalyzes intracellular 3, 5, 3' triiodothyronine (T(3)) production from thyroxine (T(4)), and its messenger RNA mRNA is highly expressed in human, but not rodent, myocardium. The goal of this study was to identify the effects of D(2) expression in the mouse myocardium on cardiac function and gene expression. We prepared transgenic (TG) mice in which human D(2) expression was driven by the alpha-MHC promoter. Despite high myocardial D(2) activity, myocardial T(3) was, at most, minimally increased in TG myocardium. Although, plasma T(3) and T(4), growth rate as well as the heart weight was not affected by TG expression, there was a significant increase in heart rate of the isolated perfused hearts, from 284 +/-12 to 350 +/- 7 beats/min. This was accompanied by an increase in pacemaker channel (HCN2) but not alpha-MHC or SERCA II messenger RNA levels. Biochemical studies and (31)P-NMR spectroscopy showed significantly lower levels of phosphocreatine and creatine in TG hearts. These results suggest that even mild chronic myocardial thyrotoxicosis, such as may occur in human hyperthyroidism, can cause tachycardia and associated changes in high energy phosphate compounds independent of an increase in SERCA II and alpha-MHC. OBJECTIVE: A decrease in plasma T3 concentration is a frequent finding in patients with heart failure. However, the role of this 'low T3 syndrome' on disease evolution has never been clarified. As phenotypic and functional cardiomyocyte impairments are alterations that correlate with the failing myocardium, we studied the long-term effects of T3 deprivation on human cardiomyocyte structure and calcium handling. METHODS: Atrial cardiomyocytes and myocardial tissue were cultured with or without 3 nM T3. Microscopical examination of structural features was followed by analysis of alpha-sarcomeric actinin and sarcoplasmic reticulum calcium ATP-ase (SERCA-2) content. Calcium handling was studied by [Ca2+](i) imaging. RESULTS: When stimulated with cyclopiazonic acid, a SERCA-2 inhibitor, T3-deprived cardiomyocytes showed significantly faster (P=0.03) and more transient (P=0.04) increases in [Ca(2+)](i) than T3-supplemented cells. Moreover, in the T3-free cultures a significantly lower number of cells (P=0.003) responded to caffeine, a typical activator of sarcoplasmic reticulum Ca(2+)-release channel. T3-deprived cardiomyocytes also presented altered morphology with larger dimensions than T3-supplemented cells (P < 0.0001). Additionally, in T3-deprived samples alpha-sarcomeric actinin and SERCA-2 protein levels were reduced to 65.6 +/- 3% (P < 0.0001) and 74.1 +/- 4% (P=0.005), respectively, when compared with the T3-supplemented group. CONCLUSIONS: Our data show that human cardiomyocyte calcium handling and phenotype are strongly influenced by T3 suggesting important implications of the 'low T3 syndrome' on the progression of heart failure. Physiological and pathological cardiac hypertrophy have directionally opposite changes in transcription of thyroid hormone (TH)-responsive genes, including alpha- and beta-myosin heavy chain (MyHC) and sarcoplasmic reticulum Ca(2+)-ATPase (SERCA), and TH treatment can reverse molecular and functional abnormalities in pathological hypertrophy, such as pressure overload. These findings suggest relative hypothyroidism in pathological hypertrophy, but serum levels of TH are usually normal. We studied the regulation of TH receptors (TRs) beta1, alpha1, and alpha2 in pathological and physiological rat cardiac hypertrophy models with hypothyroid- and hyperthyroid-like changes in the TH target genes, alpha- and beta-MyHC and SERCA. All 3 TR subtypes in myocytes were downregulated in 2 hypertrophy models with a hypothyroid-like mRNA phenotype, phenylephrine in culture and pressure overload in vivo. Myocyte TRbeta1 was upregulated in models with a hyperthyroid-like phenotype, TH (triiodothyronine, T3), in culture and exercise in vivo. In myocyte culture, TR overexpression, or excess T3, reversed the effects of phenylephrine on TH-responsive mRNAs and promoters. In addition, TR cotransfection and treatment with the TRbeta1-selective agonist GC-1 suggested different functional coupling of the TR isoforms, TRbeta1 to transcription of beta-MyHC, SERCA, and TRbeta1, and TRalpha1 to alpha-MyHC transcription and increased myocyte size. We conclude that TR isoforms have distinct regulation and function in rat cardiac myocytes. Changes in myocyte TR levels can explain in part the characteristic molecular phenotypes in physiological and pathological cardiac hypertrophy. Exercise training improves the aging-induced downregulation of myosin heavy chain (MHC) and sarcoplasmic reticulum (SR) Ca(2+)-ATPase, which participate in the regulation of cardiac contraction and relaxation. Thyroid hormone receptor (TR), a transcriptional activator, affected the regulation of gene expression of MHC and SR Ca(2+)-ATPase. We hypothesized that myocardial TR signaling contributes to a molecular mechanism of exercise training-induced improvement of MHC and SR Ca(2+)-ATPase genes with cardiac function in old age. We investigated whether TR signaling and gene expression of MHC and SR Ca(2+)-ATPase in the aged heart are affected by exercise training, using the hearts of sedentary young rats (4 mo old), sedentary aged rats (23 mo old), and trained aged rats (23 mo old, swimming training for 8 wk). Trained aged rats showed improvement in cardiac function. Expression of TR-alpha1 and TR-beta1 proteins in the heart were significantly lower in sedentary aged rats than in sedentary young rats and were significantly higher in trained aged rats than in sedentary aged rats. The activity of TR DNA binding to the transcriptional regulatory region in the alpha-MHC and SR Ca(2+)-ATPase genes and the mRNA and protein expression of alpha-MHC and SR Ca(2+)-ATPase in the heart and plasma 3,3'-triiodothyronine and thyroxine levels were altered in association with changes in the myocardial TR protein levels. These findings suggest that exercise training improves the aging-induced downregulation of myocardial TR signaling-mediated transcription of MHC and SR Ca(2+)-ATPase genes, thereby contributing to the improvement of cardiac function in trained aged hearts. Maternal hypothyroxinemia during early pregcy poses an increased risk for poor neuropsychological development of the fetus. We tested the hypothesis that maternal hypothyroidism before the onset of fetal thyroid function also affects postnatal development of heart and lungs. This question was addressed in transgenic mice that express herpes simplex virus thymidine kinase in their thyroidal follicle cells. Treatment with ganciclovir rendered these mice severely hypothyroid because viral thymidine kinase converts ganciclovir into a cytotoxic nucleoside analog. Since ganciclovir crosses the placenta, it also destroyed the thyroid of transgenic embryos while leaving the thyroids of nontransgenic littermates unaffected. Hypothyroidism of both mother and fetus did not affect prenatal heart and lung development. However, the postnatal switch from beta- to alpha-myosin heavy chain (beta- and alpha-MHC, respectively) gene expression and the increase of SERCA-2a mRNA expression did not occur in the ventricular myocardium of either the transgenic (thyroid destroyed) or nontransgenic (intact thyroid) offspring of hypothyroid mothers. Similarly, postnatal animals of the latter two groups retained elevated surfactant protein (SP) A, B, and C mRNA levels in their alveolar epithelium. In hypothyroid pups from hypothyroid mothers, these changes were accompanied by decreased alveolar septation. Our study shows that these effects of maternal hypothyroidism become manifest after birth and are aggravated by the concomitant existence of neonatal hypothyroidism. Hypothyroid heart displays a phenotype of cardioprotection against ischemia and this study investigated whether administration of dronedarone, an amiodarone-like compound that has been shown to preferentially antagonize thyroid hormone binding to thyroid hormone receptor alpha1 (TRalpha1), results in a similar effect. Dronedarone was given in Wistar rats (90 mg/kg, once daily (od) for 2 weeks) (DRON), while untreated animals served as controls (CONT). Hypothyroidism (HYPO) was induced by propylthiouracil administration. Isolated rat hearts were perfused in Langendorff mode and subjected to 20 minutes of zero-flow global ischemia (I) followed by 45 minutes of reperfusion (R). 3,5,3' Triiodothyronine remained unchanged while body weight and food intake were reduced. alpha-Myosin heavy chain (alpha-MHC) decreased in DRON while beta-myosin heavy chain (beta-MHC) and sarcoplasmic reticulum Ca2+ adenosine triphosphatase (ATPase) expression (SERCA) was similar to CONT. In HYPO, alpha-MHC and SERCA were decreased while beta-MHC was increased. Myocardial glycogen content was increased in both DRON and HYPO. In DRON, resting heart rate and contractility were reduced and ischemic contracture was significantly suppressed while postischemic left ventricular end-diastolic pressure and lactate dehydrogenase release (IU/L min) after I/R were significantly decreased. In conclusion, dronedarone treatment results in cardioprotection by selectively mimicking hypothyroidism. This is accompanied by a reduction in body weight because of the suppression of food intake. TRs might prove novel pharmacologic targets for the treatment of cardiovascular illnesses. Thyroid hormone (TH) is critical for cardiac development and heart function. In heart disease, TH metabolism is abnormal, and many biochemical and functional alterations mirror hypothyroidism. Although TH therapy has been advocated for treating heart disease, a clear benefit of TH has yet to be established, possibly because of peripheral actions of TH. To assess the potential efficacy of TH in treating heart disease, type 2 deiodinase (D2), which converts the prohormone thyroxine to active triiodothyronine (T3), was expressed transiently in mouse hearts by using the tetracycline transactivator system. Increased cardiac D2 activity led to elevated cardiac T3 levels and to enhanced myocardial contractility, accompanied by increased Ca(2+) transients and sarcoplasmic reticulum (SR) Ca(2+) uptake. These phenotypic changes were associated with up-regulation of sarco(endo)plasmic reticulum calcium ATPase (SERCA) 2a expression as well as decreased Na(+)/Ca(2+) exchanger, beta-myosin heavy chain, and sarcolipin (SLN) expression. In pressure overload, targeted increases in D2 activity could not block hypertrophy but could completely prevent impaired contractility and SR Ca(2+) cycling as well as altered expression patterns of SERCA2a, SLN, and other markers of pathological hypertrophy. Our results establish that elevated D2 activity in the heart increases T3 levels and enhances cardiac contractile function while preventing deterioration of cardiac function and altered gene expression after pressure overload. Pressure overload-induced cardiac hypertrophy leads to decreased contractile performance, frequently progressing to heart failure. Cardiac hypertrophy and heart failure can be accompanied by the so-called sick thyroid syndrome, resulting in decreased serum T(3) levels along with decreased expression of thyroid hormone receptors (TRalpha1 and TRbeta1) and sarco(endo)plasmic reticulum Ca-ATPase (SERCA). Because the binding of T(3) occupied receptors to the thyroid response elements in the SERCA promotor can increase gene expression, we wanted to determine whether increasing TR expression in the hypertrophied heart could also improve SERCA expression and cardiac function. Mice subjected to aortic constriction to generate pressure overload-induced hypertrophy were also subjected to gene therapy using adeno-associated virus (AAV) expressing either TRalpha1 or TRbeta1, with LacZ expressing AAV serving as control. After 8 wk of aortic constriction, a similar degree of hypertrophy was observed in all three groups; however, mice treated with TRalpha1 or TRbeta1 showed improved contractile function. Administration of a physiological dose of T(3) increased serum T(3) levels only into the lower range of normal. This T(3) dose, with or without AAV TR treatment, did not result in any significant increase in contractile performance. Calcium transients measured in isolated myocytes also exhibited an enhanced rate of decay associated with TRalpha1 or TRbeta1 treatment. Western blot analysis showed increased SERCA expression in the TRalpha1- or TRbeta1-treated groups relative to the LacZ-treated control group. These results demonstrate that increasing TR expression in the hypertrophied heart is associated with an improvement in contractile function and increased SERCA expression. Thyroid hormone (TH) is critical for tissue differentiation at early stages of development, induces physiological hypertrophy and regulates the expression of important contractile proteins such as myosin heavy chain (MHC) isoform and calcium cycling proteins. Furthermore, TH seems to control the response to stress by regulating important cardioprotective molecules such as heat shock proteins (HSPs). Thus, the present study investigated whether TH administration immediately after acute myocardial infarction can favourably remodel the post-infarcted myocardium. Acute myocardial infarction was induced in rats by coronary artery ligation (AMI, n=10), while SHAM-operated animals served as controls (SHAM, n = 8). TH was administered for 13 weeks (AMI-THYR, n = 9). Cardiac contractile function and left ventricular (LV) chamber remodelling was assessed by serial echocardiography and in Langendorff heart preparations. AMI significantly reduced LV ejection fraction (EF%); 30.0 (s.e.m, 2.3) Vs. 73.8 (1.8) in SHAM, P < 0.05. In addition, +dp/dt and -dp/dt (in mmHg/s) were 4,051 (343) and 2,333 (118) respectively for SHAM Vs. 2,102 (290) and 1,368 (181) for AMI, P < 0.05. With TH treatment, EF% was increased to 49.5 (2.7) in AMI-THYR, P < 0.05, while +dp/dt and -dp/dt (in mmHg/s) were 3,708 (231) and 2,035 (95) for AMI-THYR, P < 0.05 Vs. AMI. A marked elevation of the expression of beta-MHC and a reduced ratio of SERCA/Phospholamban were found in viable myocardium of AMI hearts, which was prevented by TH. Furthermore, heat shock protein 70 myocardial content was decreased in AMI hearts and was significantly increased after TH treatment. An ellipsoidal reshaping of LV chamber was observed with TH; cardiac sphericity index, (ratio of long/short axis, SI), was 1.98 (0.03) for SHAM, 1.52 (0.05) for AMI and 1.72(0.02) for AMI-THYR, P < 0.05. In conclusion, long-term TH administration immediately after AMI results in sustained improvement of cardiac haemodynamics. Reduced expression of sarcoplasmic reticulum calcium ATPase (SERCA)2 and other genes in the adult cardiac gene program has raised consideration of an impaired responsiveness to thyroid hormone (T3) that develops in the advanced failing heart. Here, we show that human and murine cardiomyopathy hearts have increased expression of friend of GATA (FOG)-2, a cardiac nuclear hormone receptor corepressor protein. Cardiac-specific overexpression of FOG-2 in transgenic mice led to depressed cardiac function, activation of the fetal gene program, congestive heart failure, and early death. SERCA2 transcript and protein levels were reduced in FOG-2 transgenic hearts, and FOG-2 overexpression impaired T3-mediated SERCA2 expression in cultured cardiomyocytes. FOG-2 physically interacts with thyroid hormone receptor-alpha1 and abrogated even high levels of T3-mediated SERCA2 promoter activity. These results demonstrate that SERCA2 is an important target of FOG-2 and that increased FOG-2 expression may contribute to a decline in cardiac function in end-stage heart failure by impaired T3 signaling. Besides the well-characterized genomic action of thyroid hormone (TH), mediated by thyroid hormone receptors (TRs), accumulating data support the so-called non-genomic action of TH, which is often related to activation of signalling pathways. In this study, we sought to determine whether TH activates intracellular signalling pathways in the adult cardiac myocytes and whether such activation modulates cell growth and the expression of target proteins important in cardiac function. We demonstrate that TH promotes a rapid increase in the phosphorylation of several kinases, ERK1/2, PKCdelta, p38-MAPK and Akt. This activation is inhibited by triiodothyroacetic acid (triac), which is a TH analogue known to displace the hormone from membrane bound receptors, indicating that this TH effect is mediated through a cell membrane-initiated mechanism. Furthermore, using specific inhibitors of the TH-activated kinases, we show that the long-term effects of TH on the expression of sarcoplasmic reticulum Ca(2+)-ATPase (SERCA), alpha- and beta-myosin heavy chain (MHC) and cell growth are reverted, implying that what is initiated as a non-genomic action of the hormone interfaces with genomic effects. These data provide further insights into the underlying mechanisms of TH action in the heart with potentially important implications in the management of cardiac pathology. Thyroid hormones play a major role in the development and function of several organs, especially the brain. The actions of thyroid hormones are exerted through the interaction of T3 with nuclear receptors and regulation of gene expression. The present study analyzed the effects of hypothyroidism and T3 administration on gene expression in the rat brain and cerebellum during the postnatal period. To obtain hypothyroid pups, antithyroid drugs were administered to pregt rats from gestational day 9, and after delivery. T3 was administered to the pups, at single daily doses of 5ng/g body weight from postnatal day 11 to 15. The pups were sacrificed 24hours after the last injection. Hypothyroid neonates showed increased cholesterol levels and decreased expression of D1 in liver and of Serca-2 in heart, which were normalized with T3 treatment. In the brain, there was decreased expression of Ngrn and Rasd2 in the striatum and of the genes encoding sinatotagmin12 (Syt12), hairless (Hr), neurotrofina3 (Nt3) and RevErbAα(Nrd1d) in the cerebellum, which were also normalized by T3 treatment. These results demonstrate that during the postnatal period, T3 reaches the brain and directly influences gene expression in this organ. In parallel, we studied the possible actions of a T3 analog, Kb430, which in vitro binds preferentially to thyroid receptor α (TRα). This compound had no effect on any of the parameters studied. To investigate whether the lack of activity of this compound was due to rapid metabolism, we compared its activity with that of T3 in T3 receptor transactivation assays using the reporter gene chloramphenicol acetyl transferase in Cos7 cells transiently expressed through TRα or TRα transfection. The results indicate that Kb430 lacks biological activity.

Which trancription factor activates the betalain pathway?

The beet Y locus encodes an anthocyanin MYB-like protein that activates the betalain red pigment pathway.

Nearly all flowering plants produce red/violet anthocyanin pigments. Caryophyllales is the only order containing families that replace anthocyanins with unrelated red and yellow betalain pigments. Close biological correlation of pigmentation patterns suggested that betalains might be regulated by a conserved anthocyanin-regulating transcription factor complex consisting of a MYB, a bHLH and a WD repeat-containing protein (the MBW complex). Here we show that a previously uncharacterized anthocyanin MYB-like protein, Beta vulgaris MYB1 (BvMYB1), regulates the betalain pathway in beets. Silencing BvMYB1 downregulates betalain biosynthetic genes and pigmentation, and overexpressing BvMYB1 upregulates them. However, unlike anthocyanin MYBs, BvMYB1 will not interact with bHLH members of heterologous anthocyanin MBW complexes because of identified nonconserved residues. BvMYB1 resides at the historic beet pigment-patterning locus, Y, required for red-fleshed beets. We show that Y and y express different levels of BvMYB1 transcripts. The co-option of a transcription factor regulating anthocyanin biosynthesis would be an important evolutionary event allowing betalains to largely functionally replace anthocyanins.

List common symptoms of patients with the DOORS syndrome.

DOORS syndrome is a constellation of deafness, onychodystrophy, osteodystrophy, mental retardation, and seizures. It is a rare autosomal recessive disorder of unknown cause.

Author information: (1)Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA. (2)Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK. (3)Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA; Department of Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine, Houston, TX, USA. (4)Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA. (5)Department of Pediatrics, Toyohashi Municipal Hospital, Toyohashi, Aichi, Japan. (6)Children's Hospital Central California, Madera, California, USA. (7)Genetics Service, Belfast City Hospital, Belfast, Ireland. (8)Medical Genetics Service, Clinical Hospital of Porto Alegre, Porto Alegre, Brazil. (9)Department of Medical Genetics, University Hospital Antwerp, 2650 Antwerp, Belgium. (10)Department of Medical Genetics, Poznañ University of Medical Sciences, Poznañ, Poland. (11)Medical Genetics Department, Istanbul Medical Faculty, Istanbul University, Turkey. (12)Department of Genetics, University of Groningen, Groningen, Netherlands. (13)Department of Pediatric Genetics, Amrita Institute of Medical Sciences and Research Centre, Kerala, India. (14)Genetic Health Service New Zealand-Northern Hub, Auckland City Hospital, Auckland, New Zealand. (15)Pediatric Neurology, Braunschweig Hospital, Braunschweig, Germany. (16)Department of Pediatrics, Saveetha Medical College and Hospital, Saveetha University, Chennai, Tamil Nadu, 600077, India. (17)Division of Genetics, Children's Mercy Hospitals and Clinics and the University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA. (18)Department of Medical Genetics, Montreal Children's Hospital, McGill University Health Center, Quebec, Canada. (19)Department of Pediatrics, NKP Salve Institute of Medical Sciences and Lata Mangeshkar Hospital, Maharashtra, India. (20)University of Washington Medical Center, Seattle, WA, USA. (21)Center for Human Genetics, Facultad de Medicina, Clínica Alemana-Universidad del Desarrollo, Santiago, Chile. (22)Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA. (23)Department of Clinical Genetics, Churchill Hospital, Oxford, UK. (24)Clinical Genetics Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK. (25)Centre Référence Anomalie Développement et Syndromes Malformatifs, Centre Hospitalier Universitaire de Nice, France. (26)Kariminejad-Najmabadi Pathology and Genetics Center, Tehran, Iran. (27)Manchester Centre for Genomic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; Manchester Centre for Genomic Centre for Genetic Medicine, Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; St Mary's Hospital, Manchester Academic Health Science Centre, Manchester, UK. (28)Department of Medical Genetics, University Medical Center Utrecht, Utrecht, Netherlands. (29)Institut für Humangenetik, University of Duisburg-Essen, University Hospital Essen, Essen, Germany. (30)Department of Pediatrics and Translational Genetics, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands. (31)Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA. (32)Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Howard Hughes Medical Institutes, Houston, TX, USA. Electronic address: [email protected]. (33)Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK; Epilepsy Society, Buckinghamshire, UK. Electronic address: [email protected].

Which is the most well-accepted method for Down syndrome non-invasive prenatal diagnosis?

Currently, two applications for NIPD of Down syndrome have been developed with potential and have displayed positive results; the NIPD using next-generation sequencing technologies and the NIPD using the methylated DNA immunoprecipitation (MeDIP) real-time quantitative polymerase chain reaction (qPCR). This study examined the methylation difference in AIRE and RASSF1A between maternal and placental DNA, and the implication of this difference in the identification of free fetal DNA in maternal plasma and in prenatal diagnosis of trisomy 21. Diagnosis of trisomy 21 was established according to the ratio of fetal-specific AIRE to RASSF1A in maternal plasma. Both methods confirmed that AIRE and RASSF1A were hypomethylated in maternal blood cells but hypermethylated in placental or chorionic villus tissues. It was concluded that hypermethylated AIRE and RASSF1A may serve as fetal-specific markers for the identification of fetal DNA in maternal plasma and may be used for noninvasive prenatal diagnosis of trisomy 21.

Both intact fetal cells as well as cell-free fetal DNA are present in the maternal circulation and can be recovered for non-invasive prenatal genetic diagnosis. Although methods for enrichment and isolation of rare intact fetal cells have been challenging, diagnosis of fetal chromosomal aneuploidy including trisomy 21 in first- and second-trimester pregcies has been achieved with a 50-75% detection rate. Similarly, cell-free fetal DNA can be reliably recovered from maternal plasma and assessed by quantitative PCR to detect fetal trisomy 21 and paternally derived single gene mutations. Real-time PCR assays are robust in detecting low-level fetal DNA concentrations, with sensitivity of approximately 95-100% and specificity near 100%. Comparing intact fetal cell versus cell-free fetal DNA methods for non-invasive prenatal screening for fetal chromosomal aneuploidy reveals that the latter is at least four times more sensitive. These preliminary results do not support a relationship between frequency of intact fetal cells and concentration of cell-free fetal DNA. The above results imply that the concentration of fetal DNA in maternal plasma may not be dependent on circulating intact fetal cells but rather be a product of growth and cellular turnover during embryonic or fetal development. This report describes the first identification and characterization of three chromosome-21-specific DNA sequences (and reference sequences from other chromosomes) that are differentially methylated between peripheral blood and placental tissue, with the aim of providing epigenetic biomarkers for quantifying cell-free fetal DNA in maternal plasma. To select sequences to be screened for differential methylation, three strategies were adopted: (i) investigating promoters of highly differentially expressed genes; (ii) choosing 'random' promoter regions; and (iii) choosing 'random' non-promoter regions. Over 200 pre-selected DNA sequences were screened using a methylation-specific restriction enzyme assay. Differentially methylated sequences located at 21q22.3 (AIRE, SIM2 and ERG genes), 1q32.1 (CD48 gene and FAIM3 gene), 2p14 (ARHGAP25 gene) and 12q24 (SELPLG gene) were identified. Bisulphite conversion confirmed that CpG sites within the AIRE promoter region are highly differentially methylated, and optimized methylation-specific primers for this region that are highly specific for placental DNA were devised. Next, it was shown that the methylation status of chorionic villus sample DNA from first trimester pregcies matched the hypermethylated state of term placenta. Thus there is no indication of a difference in methylation status between early and term pregcy for the sequences tested. The identified sequences constitute candidate biomarkers for non-invasive prenatal diagnosis of Down syndrome. BACKGROUND: Obtaining fetal DNA or RNA by either chorionic villus sampling (CVS) or amniocentesis is currently, the gold standard prenatal diagnosis. However, these invasive procedures carry risk of miscarriage. A reliable method for non-invasive prenatal diagnosis (NIPD) has long been sought to reduce the risk of miscarriage. METHODS: Cell-free fetal RNA was extracted from the plasma of peripheral blood from 121 women 9-20 weeks of pregcy. Five single nucleotide polymorphism (SNP) loci in PLAC4 gene were analyzed by reverse transcriptase multiplex ligation-dependent probe amplification (RT-MLPA), followed by capillary electrophoresis. Karyotype analysis was used for confirmation of prenatal diagnosis of trisomy 21. RESULTS: Of 121 samples, 23 were diagnosed with trisomy 21, 87 with normal ploidy, nine had all five SNP loci homozygous and two had one heterozygous SNP locus. Comparing with karyotype analysis, the diagnostic sensitivity and specificity of RT-MLPA were 92% and 100%, respectively. CONCLUSIONS: RT-MLPA is a convenient and reliable method for the diagnosis of trisomy 21. We have shown that this method has good specificity, high sensitivity, and high throughput, making this technique applicable for NIPD in clinical practice. This study examined the methylation difference in AIRE and RASSF1A between maternal and placental DNA, and the implication of this difference in the identification of free fetal DNA in maternal plasma and in prenatal diagnosis of trisomy 21. Maternal plasma samples were collected from 388 singleton pregcies, and placental or chorionic villus tissues from 112 of them. Methylation-specific PCR (MSP) and methylation-sensitive restriction enzyme digestion followed by fluorescent quantitative PCR (MSRE + PCR) were employed to detect the maternal-fetal methylation difference in AIRE and RASSF1A. Diagnosis of trisomy 21 was established according to the ratio of fetal-specific AIRE to RASSF1A in maternal plasma. Both methods confirmed that AIRE and RASSF1A were hypomethylated in maternal blood cells but hypermethylated in placental or chorionic villus tissues. Moreover, the differential methylation for each locus could be seen during the whole pregt period. The positive rates of fetal AIRE and RASSF1A in maternal plasma were found to be 78.1% and 82.1% by MSP and 94.8% and 96.9% by MSRE + PCR. MSRE + PCR was superior to MSP in the identification of fetal-specific hypermethylated sequences (P<0.05). Based on the data from 266 euploidy pregcies, the 95% reference interval of the fetal AIRE/RASSF1A ratio in maternal plasma was 0.33-1.77, which was taken as the reference value for determining the numbers of fetal chromosome 21 in 102 pregcies. The accuracy rate in 98 euploidy pregcies was 96.9% (95/98). Three of the four trisomy 21 pregcies were confirmed with this method. It was concluded that hypermethylated AIRE and RASSF1A may serve as fetal-specific markers for the identification of fetal DNA in maternal plasma and may be used for noninvasive prenatal diagnosis of trisomy 21. INTRODUCTION: Non-invasive prenatal diagnosis (NIPD) of Down syndrome is rapidly evolving. Currently, two applications for NIPD of Down syndrome have been developed with potential and have displayed positive results; the NIPD using next-generation sequencing technologies and the NIPD using the methylated DNA immunoprecipitation (MeDIP) real-time quantitative polymerase chain reaction (qPCR). AREAS COVERED: The MeDIP real-time qPCR approach is based on the identification of differentially methylated regions (DMRs) and their use for discriminating normal from Down syndrome cases. DMRs were identified using high-resolution oligo-arrays. A subgroup of DMRs was selected for further investigation. Through the design of a discrimit equation which combines the results obtained from different DMRs, normal and abnormal cases are correctly classified indicating 100% sensitivity and specificity. EXPERT OPINION: Previous studies have also identified DMRs between non-pregt female blood and placental DNA. However, these methods have been associated with a number of limitations including the low sensitivity and/or specificity of the assays, the limited number of identified DMRs or methylation sensitive sites and SNPs located on DMRs. These limitations have been overawed by the development of the MeDIP real-time qPCR-based methodology. OBJECTIVE: To study whether pregt women would like to be informed if sex chromosomal abnormalities (SCA) were suspected with the non-invasive prenatal diagnosis of fetal Down syndrome (the NIFTY) test. METHODS: Two hundred and one patients carried a singleton pregcy requesting the NIFTY test were invited to give their preferences if there was suspicion of SCA by the NIFTY test. RESULTS: Over 93.5% were ethnic Chinese, with a mean age of 36. Prior Down screening was positive in 66 (32.8%). Over 50% of subjects considered SCA to be better in terms of disability compared to Down syndrome, and only 5.2% considered SCA to be worse. Yet, the majority (198, 98.5%) indicated that they wanted to be informed if there was suspicion of SCA. Of whom 34.8% would have an amniocentesis for confirmation, while 57.1% were not certain, indicating the possibility of accepting these conditions. CONCLUSION: Besides screening Down syndrome by NIFTY, most pregt women would also like to be informed if there was suspicion of SCA. Those screened positive should be counseled by those with experience in genetics to avoid unnecessary pregcy termination. OBJECTIVES: To use proteomics to identify and characterize proteins in maternal serum from patients at high-risk for fetal trisomy 21, trisomy 18, and trisomy 13 on the basis of ultrasound and maternal serum triple tests. METHODS: We performed a comprehensive proteomic analysis on 23 trisomy cases and 85 normal cases during the early second trimester of pregcy. Protein profiling along with conventional sodium dodecyl sulfate polyacrylamide gel electrophoresis/Tandem mass spectrometry analysis was carried out to characterize proteins associated with each trisomy condition and later validated using Western blot. RESULTS: Protein profiling approach using surface enhanced laser desorption/ionization time-of-flight mass (SELDI-TOF/MS) spectrometry resulted in the identification of 37 unique hydrophobic proteomic features for three trisomy conditions. Using sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by Matrix Assisted Laser Desorption Ionization - Time of Flight/Time of Flight (MALDI-TOF/TOF) and western blot, glyco proteins such as alpha-1-antitrypsin, apolipoprotein E, apolipoprotein H, and serum carrier protein transthyretin were identified as potential maternal serum markers for fetal trisomy condition. The identified proteins showed differential expression at the subunit level. CONCLUSIONS: Maternal serum protein profiling using proteomics may allow non-invasive diagnostic testing for the most common trisomies and may complement ultrasound-based methods to more accurately determine pregcies with fetal aneuploidies. BACKGROUND: Non-invasive methods to assess the foetal genome during pregcy will provide new opportunities to offer pregt women a more comprehensive genetic diagnosis of their established foetus. The aim of this study was to determine the presence and frequency of foetal cells in transcervical cell (TCC) mucus samples from pregt women and determine their suitability for early prenatal diagnosis. METHODS: Syncytiotrophoblasts in aspirated TCC mucus samples were identified by immunostaining with the foetal-specific antibody NDOG1. Genetic analysis of foetal cells was performed by laser capture microdissection and quantitative fluorescent PCR (QF-PCR). RESULTS: In 116 of 207 (56%) TCC samples, abundant syncytiotrophoblasts were retrieved. However, when TCC samples were stratified for the presence of chorionic villous fragments, syncytiotrophoblasts were identified in 85 of 109 (78%) samples. Significant numbers of syncytiotrophoblasts were found in TCC samples collected between 6 and 9weeks of gestation (mean 741, range 25-2884). QF-PCR analysis of NDOG1 positive syncytiotrophoblasts and matching maternal DNA confirmed their foetal origin and correct foetal cell sexing was achieved in 97% of TCC samples. The one discordant sex diagnosis was associated with a dizygotic dichorionic twin pregcy resulting from the implantation of a female T21 embryo and a normal male embryo, where the female T21 foetus had succumbed at 6weeks of gestation and was vanishing. CONCLUSIONS: Syncytiotrophoblasts can be successfully isolated from TCC samples and represent a suitable source of cells for genetic analysis of the established foetus in early pregcy. The study highlights a vanishing twin as a potential cause for discordant non-invasive prenatal test results.

Is the H3K4me3 histone mark related to transcriptional initiation or elongation?

H3K4me3 is associated with transcriptionally active genes, but its function in the transcription process is still unclear. It is well known to occur in the promoter region of genes for transcription activation but its levels correlate positively with the antisense expression levels of the associated sense genes implying that it may be also involved in the activation of antisense transcription. Although it is mostly associated with transcription initiation H3K4me3 levels determine the efficiency of transcription elongation.

Trimethylation of lysine residue K4 of histone H3 (H3K4me3) strongly correlates with active promoters for RNA polymerase II-transcribed genes. Several reader proteins, including the basal transcription factor TFIID, for this nucleosomal mark have been identified. Its TAF3 subunit specifically binds the H3K4me3 mark via its conserved plant homeodomain (PHD) finger. Here, we report the solution structure of the TAF3-PHD finger and its complex with an H3K4me3 peptide. Using a combination of NMR, mutagenesis, and affinity measurements, we reveal the structural basis of binding affinity, methylation-state specificity, and crosstalk with asymmetric dimethylation of R2. A unique local structure rearrangement in the K4me3-binding pocket of TAF3 due to a conserved sequence insertion underscores the requirement for cation-pi interactions by two aromatic residues. Interference by asymmetric dimethylation of arginine 2 suggests that a H3R2/K4 "methyl-methyl" switch in the histone code dynamically regulates TFIID-promoter association. An organism's genome sequence serves as a blueprint for the proteins and regulatory RNAs essential for cellular function. The genome also harbors cis-acting non-coding sequences that control gene expression and are essential to coordinate regulatory programs during embryonic development. However, the genome sequence is largely identical between cell types within a multi-cellular organism indicating that factors such as DNA accessibility and chromatin structure play a crucial role in governing cell-specific gene expression. Recent studies have identified particular chromatin modifications that define functionally distinct cis regulatory elements. Among these are forms of histone 3 that are mono- or tri-methylated at lysine 4 (H3K4me1 or H3K4me3, respectively), which bind preferentially to promoter and enhancer elements in the mammalian genome. In this work, we investigated whether these modified histones could similarly identify cis regulatory elements within the zebrafish genome. By applying chromatin immunoprecipitation followed by deep sequencing, we find that H3K4me1 and H3K4me3 are enriched at transcriptional start sites in the genome of the developing zebrafish embryo and that this association correlates with gene expression. We further find that these modifications associate with distal non-coding conserved elements, including known active enhancers. Finally, we demonstrate that it is possible to utilize H3K4me1 and H3K4me3 binding profiles in combination with available expression data to computationally identify relevant cis regulatory sequences flanking syn-expressed genes in the developing embryo. Taken together, our results indicate that H3K4me1 and H3K4me3 generally mark cis regulatory elements within the zebrafish genome and indicate that further characterization of the zebrafish using this approach will prove valuable in defining transcriptional networks in this model system. Trimethylation of histone H3 Lys 4 (H3K4me3) is a mark of active and poised promoters. The Set1 complex is responsible for most somatic H3K4me3 and contains the conserved subunit CxxC finger protein 1 (Cfp1), which binds to unmethylated CpGs and links H3K4me3 with CpG islands (CGIs). Here we report that Cfp1 plays uticipated roles in organizing genome-wide H3K4me3 in embryonic stem cells. Cfp1 deficiency caused two contrasting phenotypes: drastic loss of H3K4me3 at expressed CGI-associated genes, with minimal consequences for transcription, and creation of "ectopic" H3K4me3 peaks at numerous regulatory regions. DNA binding by Cfp1 was dispensable for targeting H3K4me3 to active genes but was required to prevent ectopic H3K4me3 peaks. The presence of ectopic peaks at enhancers often coincided with increased expression of nearby genes. This suggests that CpG targeting prevents "leakage" of H3K4me3 to inappropriate chromatin compartments. Our results demonstrate that Cfp1 is a specificity factor that integrates multiple signals, including promoter CpG content and gene activity, to regulate genome-wide patterns of H3K4me3. Tri-methylated H3 lysine 4 (H3K4me3) is associated with transcriptionally active genes, but its function in the transcription process is still unclear. Point mutations in the catalytic domain of ATX1 (ARABIDOPSIS TRITHORAX1), a H3K4 methyltransferase, and RNAi knockdowns of subunits of the AtCOMPASS-like (Arabidopsis Complex Proteins Associated with Set) were used to address this question. We demonstrate that both ATX1 and AtCOMPASS-like are required for high level accumulation of TBP (TATA-binding protein) and Pol II at promoters and that this requirement is independent of the catalytic histone modifying activity. However, the catalytic function is critically required for transcription as H3K4me3 levels determine the efficiency of transcription elongation. The roles of H3K4me3, ATX1, and AtCOMPASS-like may be of a general relevance for transcription of Trithorax-activated eukaryotic genes. While previous studies have shown that histone modifications could influence plant growth and development by regulating gene transcription, knowledge about the relationships between these modifications and gene expression is still limited. This study used chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-Seq), to investigate the genome-wide distribution of four histone modifications: di and trimethylation of H3K4 (H3K4me2 and H3K4me3) and acylation of H3K9 and H3K27 (H3K9ac and H3K27ac) in Oryza sativa L. japonica. By analyzing published DNase-Seq data, this study explored DNase-Hypersensitive (DH) sites along the rice genome. The histone marks appeared mainly in generic regions and were enriched around the transcription start sites (TSSs) of genes. This analysis demonstrated that the four histone modifications and the DH sites were all associated with active transcription. Furthermore, the four histone modifications were highly concurrent with transcript regions-a promising feature that was used to predict missing genes in the rice gene annotation. The predictions were further validated by experimentally confirming the transcription of two predicted missing genes. Moreover, a sequence motif analysis was constructed in order to identify the DH sites and many putative transcription factor binding sites.

What does polyadenylate-binding protein 4 (PABP4) bind to?

PABP4 binds mRNA poly(A) tails.

Poly(A) binding protein (PABP) binds mRNA poly(A) tails and affects mRNA stability and translation. We show here that there is little free PABP in NIH3T3 cells, with the vast majority complexed with RNA. We found that PABP in NIH3T3 cytoplasmic lysates and recombit human PABP can bind to AU-rich RNA with high affinity. Human PABP bound an AU-rich RNA with Kd in the nm range, which was only sixfold weaker than the affinity for oligo(A) RNA. Truncated PABP containing RNA recognition motif domains 3 and 4 retained binding to both AU-rich and oligo(A) RNA, whereas a truncated PABP containing RNA recognition motif domains 1 and 2 was highly selective for oligo(A) RNA. The inducible PABP, iPABP, was found to be even less discriminating than PABP in RNA binding, with affinities for AU-rich and oligo(A) RNAs differing by only twofold. These data suggest that iPABP and PABP may in some situations interact with other RNA regions in addition to the poly(A) tail. Tob is a member of an emerging family of anti-proliferative proteins that suppress cell growth when over-expressed. tob mRNA is highly expressed in anergic T cells and over-expression of Tob suppresses transcription of interleukin-2 (IL-2) through its interaction with Smads. Here, we identified two types of cDNA clones coding for poly(A)-binding protein (PABP) and inducible PABP (iPABP) by screening an expression cDNA library with the GST-Tob probe. Co-immunoprecipitation and GST-pull down experiments showed that Tob associated with the carboxyl-terminal region of iPABP. We then found that iPABP, like PABP, was involved in regulation of translation: iPABP enhanced translation of IL-2 mRNA in vitro. The enhanced translation of IL-2 mRNA required the 3'UTR and poly(A) sequences. Tob abrogated the enhancement of translation through its interaction with carboxyl-terminal region of iPABP in vitro. Consistently, over-expression of Tob in NIH3T3 cells, in which exogenous iPABP was stably expressed, resulted in suppression of IL-2 production from the simultaneously transfected IL-2 expression plasmid. Finally, Tob, whose expression was induced by anergic stimulation, was co-immunoprecipitated with iPABP in human T cells. These findings suggest that Tob is involved in the translational suppression of IL-2 mRNA in anergic T cells through its interaction with iPABP. The poly(A)-binding protein (PABP) is an important translation initiation factor that binds to the polyadenylated 3' end of mRNA. We have previously shown that PABP2 interacts with the RNA-dependent RNA polymerase (RdRp) and VPg-Pro of turnip mosaic virus (TuMV) within virus-induced vesicles. At least eight PABP isoforms are produced in Arabidopsis thaliana, three of which (PABP2, PABP4 and PABP8) are highly and broadly expressed and probably constitute the bulk of PABP required for cellular functions. Upon TuMV infection, an increase in protein and mRNA expression from PAB2, PAB4 and PAB8 genes was recorded. In vitro binding assays revealed that RdRp and the viral genome-linked protein (VPg-Pro) interact preferentially with PABP2 but are also capable of interaction with one or both of the other class II PABPs (i.e. PABP4 and PABP8). To assess whether PABP is required for potyvirus replication, A. thaliana single and double pab knockouts were isolated and inoculated with TuMV. All lines showed susceptibility to TuMV. However, when precise monitoring of viral RNA accumulation was performed, it was found to be reduced by 2.2- and 3.5-fold in pab2 pab4 and pab2 pab8 mutants, respectively, when compared with wild-type plants. PABP levels were most significantly reduced in the membrane-associated fraction in both of these mutants. TuMV mRNA levels thus correlated with cellular PABP concentrations in these A. thaliana knockout lines. These data provide further support for a role of PABP in potyvirus replication. Translational control of many mRNAs in developing metazoan embryos is achieved by alterations in their poly(A) tail length. A family of cytoplasmic poly(A)-binding proteins (PABPs) bind the poly(A) tail and can regulate mRNA translation and stability. However, despite the extensive biochemical characterization of one family member (PABP1), surprisingly little is known about their in vivo roles or functional relatedness. Because no information is available in vertebrates, we address their biological roles, establishing that each of the cytoplasmic PABPs conserved in Xenopus laevis [PABP1, embryonic PABP (ePABP), and PABP4] is essential for normal development. Morpholino-mediated knockdown of PABP1 or ePABP causes both anterior and posterior phenotypes and embryonic lethality. In contrast, depletion of PABP4 results mainly in anterior defects and lethality at later stages. Unexpectedly, cross-rescue experiments reveal that neither ePABP nor PABP4 can fully rescue PABP1 depletion, establishing that PABPs have distinct functions. Comparative analysis of the uncharacterized PABP4 with PABP1 and ePABP shows that it shares a mechanistically conserved core role in promoting global translation. Consistent with this analysis, each morphant displays protein synthesis defects, suggesting that their roles in mRNA-specific translational regulation and/or mRNA decay, rather than global translation, underlie the functional differences between PABPs. Domain-swap experiments reveal that the basis of the functional specificity is complex, involving multiple domains of PABPs, and is conferred, at least in part, by protein-protein interactions. Poly(A)-binding protein 1 (PABP1) has a fundamental role in the regulation of mRNA translation and stability, both of which are crucial for a wide variety of cellular processes. Although generally a diffuse cytoplasmic protein, it can be found in discrete foci such as stress and neuronal granules. Mammals encode several additional cytoplasmic PABPs that remain poorly characterised, and with the exception of PABP4, appear to be restricted in their expression to a small number of cell types. We have found that PABP4, similarly to PABP1, is a diffusely cytoplasmic protein that can be localised to stress granules. However, UV exposure unexpectedly relocalised both proteins to the nucleus. Nuclear relocalisation of PABPs was accompanied by a reduction in protein synthesis but was not linked to apoptosis. In examining the mechanism of PABP relocalisation, we found that it was related to a change in the distribution of poly(A) RNA within cells. Further investigation revealed that this change in RNA distribution was not affected by PABP knockdown but that perturbations that block mRNA export recapitulate PABP relocalisation. Our results support a model in which nuclear export of PABPs is dependent on ongoing mRNA export, and that a block in this process following UV exposure leads to accumulation of cytoplasmic PABPs in the nucleus. These data also provide mechanistic insight into reports that transcriptional inhibitors and expression of certain viral proteins cause relocation of PABP to the nucleus. Cytoplasmic poly(A) binding protein 4 (PABPC4) is an RNA-processing protein that plays an important role in the regulation of gene expression. The aim of this study was to investigate the expression pattern and identify the potential clinical significance of PABPC4 in colorectal cancer. Immunohistochemical analysis revealed that 26.7% (27/101 patients) of primary colorectal tumors and 60.5% (23/38 patients) of corresponding adjacent, normal tissues showed high cytoplasmic expression of PABPC4, whereas expression was absent in 98% (43/44 patients) of distant, normal tissues. Using Kaplan-Meier analysis, we observed that the expression of PABPC4 was significantly correlated with disease-free survival and overall survival in patients with stage II and stage III colorectal cancer (P=0.022 and P=0.020, respectively). PABPC4 expression was positively associated with survival outcome, and may have predictive value in the prognosis of patients with colorectal cancer. Taken together, our findings indicate that PABPC4 may play a role in the pathogenesis of colorectal cancer. Cytoplasmic poly(A)-binding proteins (PABPs) regulate mRNA stability and translation. Although predomitly localized in the cytoplasm, PABP proteins also cycle through the nucleus. Recent work has established that their steady-state localization can be altered by cellular stresses such as ultraviolet (UV) radiation, and infection by several viruses, resulting in nuclear accumulation of PABPs. Here, we present further evidence that their interaction with and release from mRNA and translation complexes are important in determining their sub-cellular distribution and propose an integrated model for regulated nucleo-cytoplasmic transport of PABPs. Spermiogenesis is a postmeiotic process that drives development of round spermatids into fully elongated spermatozoa. Spermatid elongation is largely controlled post-transcriptionally after global silencing of mRNA synthesis from the haploid genome. Here, rats that differentially express EGFP from a lentiviral transgene during early and late steps of spermiogenesis were used to flow sort fractions of round and elongating spermatids. Mass-spectral analysis of 2D gel protein spots enriched >3-fold in each fraction revealed a heterogeneous RNA binding proteome (hnRNPA2/b1, hnRNPA3, hnRPDL, hnRNPK, hnRNPL, hnRNPM, PABPC1, PABPC4, PCBP1, PCBP3, PTBP2, PSIP1, RGSL1, RUVBL2, SARNP2, TDRD6, TDRD7) abundantly expressed in round spermatids prior to their elongation. Notably, each protein within this ontology cluster regulates alternative splicing, sub-cellular transport, degradation and/or translational repression of mRNAs. In contrast, elongating spermatid fractions were enriched with glycolytic enzymes, redox enzymes and protein synthesis factors. Retrogene-encoded proteins were over-represented among the most abundant elongating spermatid factors identified. Consistent with these biochemical activities, plus corresponding histological profiles, the identified RNA processing factors are predicted to collectively drive post-transcriptional expression of an alternative exome that fuels finishing steps of sperm maturation and fitness.

What is the average diameter of intermediate filaments?

Intermediate filaments have an average diameter of 10 nanometers (nm).

The critical concentration required for filament assembly in vitro from highly purified desmin was determined by both turbidity and centrifugation assays. Assembly was done in the presence of 2 mM-Ca2+, 2 mM-Mg2+ or 150 mM-Na+ at 2, 22 and 37 degrees C. Similar values for critical concentration were obtained by both assays. As temperature increased, critical concentration decreased for each cation. The critical concentration was lowest in the presence of Ca2+ at 2, 22 and 37 degrees C, but was highest in the presence of 150 mM-Na+ at 2 degrees C. Negative staining showed that supernatants from the centrifugation assays contained protofilaments, protofibrils and short particles (less than 300 nm), but pellets contained long filaments (greater than 1 micron) with an average diameter of 10 nm. As the temperature increased, both the average diameter and average length of particles in the supernatant increased. Thermodynamic analysis indicated that hydrophobic interactions were domit during desmin assembly, but that ionic interactions might also be involved. Our results demonstrated that the specific cation and temperature and temperature-cation interactions all are important in assembly of desmin intermediate filaments. A new model for stratum corneum keratin structure, function, and formation is presented. The structural and functional part of the model, which hereafter is referred to as "the cubic rod-packing model", postulates that stratum corneum keratin intermediate filaments are arranged according to a cubic-like rod-packing symmetry with or without the presence of an intracellular lipid membrane with cubic-like symmetry enveloping each individual filament. The new model could account for (i) the cryo-electron density pattern of the native corneocyte keratin matrix, (ii) the X-ray diffraction patterns, (iii) the swelling behavior, and (iv) the mechanical properties of mammalian stratum corneum. The morphogenetic part of the model, which hereafter is referred to as "the membrane templating model", postulates the presence in cellular space of a highly dynamic small lattice parameter (<30 nm) membrane structure with cubic-like symmetry, to which keratin is associated. It further proposes that membrane templating, rather than spontaneous self-assembly, is responsible for keratin intermediate filament formation and dynamics. The new model could account for (i) the cryo-electron density patterns of the native keratinocyte cytoplasmic space, (ii) the characteristic features of the keratin network formation process, (iii) the dynamic properties of keratin intermediate filaments, (iv) the close lipid association of keratin, (v) the insolubility in non-denaturating buffers and pronounced polymorphism of keratin assembled in vitro, and (vi) the measured reduction in cell volume and hydration level between the stratum granulosum and stratum corneum. Further, using cryo-transmission electron microscopy on native, fully hydrated, vitreous epidermis we show that the subfilametous keratin electron density pattern consists, both in corneocytes and in viable keratinocytes, of one axial subfilament surrounded by an undetermined number of peripheral subfilaments forming filaments with a diameter of approximately 8 nm. Several aspects of the intermediate filaments' molecular architecture remain mysterious despite decades of study. The growth process and the final architecture may depend on the physical, chemical, and biochemical environment. Aiming at clarifying this issue, we have revisited the structure of the human hair follicle by means of X-ray microdiffraction. We conclude that the histology-based growth zones along the follicle are correlated to the fine architecture of the filaments deduced from X-ray microdiffraction. Our analysis reveals the existence of two major polymorph intermediate filament architectures. Just above the bulb, the filaments are characterized by a diameter of 100 Angstroms and a low-density core. The following zone upwards is characterized by the lateral aggregation of the filaments into a compact network of filaments, by a contraction of their diameter (to 75 Angstroms) and by the setting up of a long-range longitudinal ordering. In the upper zone, the small structural change associated with the tissue hardening likely concerns the terminal domains. The architecture of the intermediate filament in the upper zones could be specific to hard alpha-keratin whilst the other architecture found in the lower zone could be representative for intermediate filaments in a different environment. The prevailing model of the mechanical function of intermediate filaments in cells assumes that these 10 nm diameter filaments make up networks that behave as entropic gels, with individual intermediate filaments never experiencing direct loading in tension. However, recent work has shown that single intermediate filaments and bundles are remarkably extensible and elastic in vitro, and therefore well-suited to bearing tensional loads. Here we tested the hypothesis that the intermediate filament network in keratinocytes is extensible and elastic as predicted by the available in vitro data. To do this, we monitored the morphology of fluorescently-tagged intermediate filament networks in cultured human keratinocytes as they were subjected to uniaxial cell strains as high as 133%. We found that keratinocytes not only survived these high strains, but their intermediate filament networks sustained only minor damage at cell strains as high as 100%. Electron microscopy of stretched cells suggests that intermediate filaments are straightened at high cell strains, and therefore likely to be loaded in tension. Furthermore, the buckling behavior of intermediate filament bundles in cells after stretching is consistent with the emerging view that intermediate filaments are far less stiff than the two other major cytoskeletal components F-actin and microtubules. These insights into the mechanical behavior of keratinocytes and the cytokeratin network provide important baseline information for current attempts to understand the biophysical basis of genetic diseases caused by mutations in intermediate filament genes. Neurofilaments (NFs) are essential cytoskeletal filaments that impart mechanical integrity to nerve cells. They are assembled from three distinct molecular mass proteins that bind to each other to form a 10-nm-diameter filamentous rod with sidearm extensions. The sidearms are considered to play a critical role in modulating interfilament spacing and axonal caliber. However, the precise mechanism by which NF protrusions regulate axonal diameter remains to be well understood. In particular, the role played by individual NF protrusions in specifying interfilament distances is yet to be established. To gain insight into the role of individual proteins, we investigated the structural organization of NF architecture under different phosphorylation conditions. To this end, a physically motivated sequence-based coarse-grain model of NF brush has been developed based on the three-dimensional architecture of NFs. The model incorporates the charge distribution of sidearms, including charges from the phosphorylation sites corresponding to Lys-Ser-Pro repeat motifs. The model also incorporates the proper grafting of the real NF sidearms based on the stoichiometry of the three subunits. The equilibrium structure of the NF brush is then investigated under different phosphorylation conditions. The phosphorylation of NF modifies the structural organization of sidearms. Upon phosphorylation, a dramatic change involving a transformation from a compact conformation to an extended conformation is found in the heavy NF (NF-H) protein. However, in spite of extensive phosphorylation sites present in the NF-H subunit, the tails of the medium NF subunit are found to be more extended than the NF-H sidearms. This supports the notion that medium NF protrusions are critical in regulating NF spacings and, hence, axonal caliber. Intermediate filaments are filaments 10 nm in diameter that make up an important component of the cytoskeleton in most metazoan taxa. They are most familiar for their role as the fibrous component of α-keratins such as skin, hair, nail, and horn but are also abundant within living cells. Although they are almost exclusively intracellular in their distribution, in the case of the defensive slime produced by hagfishes, they are secreted. This article surveys the impressive diversity of biomaterials that animals construct from intermediate filaments and will focus on the mechanisms by which the mechanical properties of these materials are achieved. Hagfish slime is a dilute network of hydrated mucus and compliant intermediate filament bundles with ultrasoft material properties. Within the cytoplasm of living cells, networks of intermediate filaments form soft gels whose elasticity arises via entropic mechanisms. Single intermediate filaments or bundles are also elastic, but substantially stiffer, exhibiting modulus values similar to that of rubber. Hard α-keratins like wool are stiffer still, an effect that is likely achieved via dehydration of the intermediate filaments in these epidermal appendages. The diverse mechanisms described here have been employed by animals to generate materials with stiffness values that span an impressive eleven orders of magnitude. Mammalian appendages such as hair, quill and wool have a unique structure composed of a cuticle, a cortex and a medulla. The cortex, responsible for the mechanical properties of the fibers, is an assemblage of spindle-shaped keratinized cells bound together by a lipid/protein sandwich called the cell membrane complex. Each cell is itself an assembly of macrofibrils around 300 nm in diameter that are paracrystalline arrays of keratin intermediate filaments embedded in a sulfur-rich protein matrix. Each macrofibril is also attached to its neighbors by a cell membrane complex. In this study, we combined atomic force microscopy based o-indentation with peak-force imaging to study the omechanical properties of macrofibrils perpendicular to their axis. For indentation depths in the 200 to 500 nm range we observed a decrease of the dynamic elastic modulus at 1 Hz with increasing depth. This yielded an estimate of 1.6GPa for the lateral modulus at 1 Hz of porcupine quill's macrofibrils. Using the same data we also estimated the dynamic elastic modulus at 1 Hz of the cell membrane complex surrounding each macrofibril, i.e., 13GPa. A similar estimate was obtained independently through elastic maps of the macrofibrils surface obtained in peak-force mode at 1 kHz. Furthermore, the macrofibrillar texture of the cortical cells was clearly identified on the elasticity maps, with the boundaries between macrofibrils being 40-50% stiffer than the macrofibrils themselves. Elasticity maps after indentation also revealed a local increase in dynamic elastic modulus over time indicative of a relaxation induced strain hardening that could be explained in term of a α-helix to β-sheet transition within the macrofibrils.