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Can the FAST and ROSIER adult stroke recognition tools be applied to confirmed childhood arterial ischemic stroke? BACKGROUND: Stroke recognition tools have been shown to improve diagnostic accuracy in adults. Development of a similar tool in children is needed to reduce lag time to diagnosis. A critical first step is to determine whether adult stoke scales can be applied in childhood stroke.Our objective was to assess the applicability of adult stroke scales in childhood arterial ischemic stroke (AIS) METHODS: Children aged 1 month to < 18 years with radiologically confirmed acute AIS who presented to a tertiary emergency department (ED) (2003 to 2008) were identified retrospectively. Signs, symptoms, risk factors and initial management were extracted. Two adult stroke recognition tools; ROSIER (Recognition of Stroke in the Emergency Room) and FAST (Face Arm Speech Test) scales were applied retrospectively to all patients to determine test sensitivity. RESULTS: 47 children with AIS were identified. 34 had anterior, 12 had posterior and 1 child had anterior and posterior circulation infarcts. Median age was 9 years and 51% were male. Median time from symptom onset to ED presentation was 21 hours but one third of children presented within 6 hours. The most common presenting stroke symptoms were arm (63%), face (62%), leg weakness (57%), speech disturbance (46%) and headache (46%). The most common signs were arm (61%), face (70%) or leg weakness (57%) and dysarthria (34%). 36 (78%) of children had at least one positive variable on FAST and 38 (81%) had a positive score of > 1 on the ROSIER scale. Positive scores were less likely in children with posterior circulation stroke. CONCLUSION: The presenting features of pediatric stroke appear similar to adult strokes. Two adult stroke recognition tools have fair to good sensitivity in radiologically confirmed childhood AIS but require further development and modification. Specificity of the tools also needs to be determined in a prospective cohort of children with stroke and non-stroke brain attacks.
ROSIER scale is used for which disorder?
551fd9c06b348bb82c000012_008
{ "answer_start": [ 823 ], "text": [ "Stroke" ] }
Betrixaban compared with warfarin in patients with atrial fibrillation: results of a phase 2, randomized, dose-ranging study (Explore-Xa). AIMS: Patients with atrial fibrillation (AF) are at increased risk of stroke. Betrixaban is a novel oral factor Xa inhibitor administered once daily, mostly excreted unchanged in the bile and with low (17%) renal excretion. METHODS AND RESULTS: Patients with AF and more than one risk factor for stroke were randomized to one of three blinded doses of betrixaban (40, 60, or 80 mg once daily) or unblinded warfarin, adjusted to an international normalized ratio of 2.0-3.0. The primary outcome was major or clinically relevant non-major bleeding. The mean follow-up was 147 days. Among 508 patients randomized, the mean CHADS2 score was 2.2; 87% of patients had previously received vitamin K antagonist therapy. The time in therapeutic range on warfarin was 63.4%. There were one, five, five, and seven patients with a primary outcome on betrixaban 40, 60, 80 mg daily, or warfarin, respectively. The rate of the primary outcome was lowest on betrixaban 40 mg (hazard ratio compared with warfarin = 0.14, exact stratified log-rank P-value 0.04, unadjusted for multiple testing). Rates of the primary outcome with betrixaban 60 or 80 mg were more similar to those of wafarin. Two ischaemic strokes occurred, one each on betrixaban 60 and 80 mg daily. There were two vascular deaths, one each on betrixaban 40 mg and warfarin. Betrixaban was associated with higher rates of diarrhoea than warfarin. CONCLUSION: Betrixaban was well tolerated and had similar or lower rates of bleeding compared with well-controlled warfarin in patients with AF at risk for stroke.
Which clotting factor is inhibited by betrixaban?
55200c606b348bb82c000013_092
{ "answer_start": [ 222 ], "text": [ "xa" ] }
Andexanet alfa for the reversal of Factor Xa inhibitor related anticoagulation. Andexanet alfa is a specific reversal agent for Factor Xa inhibitors. The molecule is a recombinant protein analog of factor Xa that binds to Factor Xa inhibitors and antithrombin:LMWH complex but does not trigger prothrombotic activity. In ex vivo, animal, and volunteer human studies, andexanet alfa (AnXa) was able to dose-dependently reverse Factor Xa inhibition and restore thrombin generation for the duration of drug administration. Further trials are underway to examine its safety and efficacy in the population of patients experiencing FXa inhibitor-related bleeding.
Andexanet Alfa is an antidote of which clotting factor inhibitors?
5880b073c872c95565000003_017
{ "answer_start": [ 433 ], "text": [ "Xa" ] }
Inhibition of protein kinase C delta attenuates allergic airway inflammation through suppression of PI3K/Akt/mTOR/HIF-1 alpha/VEGF pathway. Vascular endothelial growth factor (VEGF) is supposed to contribute to the pathogenesis of allergic airway disease. VEGF expression is regulated by a variety of stimuli such as nitric oxide, growth factors, and hypoxia-inducible factor-1 alpha (HIF-1α). Recently, inhibition of the mammalian target of rapamycin (mTOR) has been shown to alleviate cardinal asthmatic features, including airway hyperresponsiveness, eosinophilic inflammation, and increased vascular permeability in asthma models. Based on these observations, we have investigated whether mTOR is associated with HIF-1α-mediated VEGF expression in allergic asthma. In studies with the mTOR inhibitor rapamycin, we have elucidated the stimulatory role of a mTOR-HIF-1α-VEGF axis in allergic response. Next, the mechanisms by which mTOR is activated to modulate this response have been evaluated. mTOR is known to be regulated by phosphoinositide 3-kinase (PI3K)/Akt or protein kinase C-delta (PKC δ) in various cell types. Consistent with these, our results have revealed that suppression of PKC δ by rottlerin leads to the inhibition of PI3K/Akt activity and the subsequent blockade of a mTOR-HIF-1α-VEGF module, thereby attenuating typical asthmatic attack in a murine model. Thus, the present data indicate that PKC δ is necessary for the modulation of the PI3K/Akt/mTOR signaling cascade, resulting in a tight regulation of HIF-1α activity and VEGF expression. In conclusion, PKC δ may represent a valuable target for innovative therapeutic treatment of allergic airway disease.
What does mTOR stands for?
5505a587f73303d458000005_002
{ "answer_start": [ 422 ], "text": [ "mammalian target of rapamycin" ] }
chromDraw: an R package for visualization of linear and circular karyotypes. Species-specific sets of chromosomes-karyotypes-are traditionally depicted as linear ideograms with individual chromosomes represented by vertical bars. However, linear visualization has its limitations when the shared collinearity and/or chromosomal rearrangements differentiating two or more karyotypes need to be demonstrated. In these instances, circular visualization might provide easier comprehension and interpretation of inter-species chromosomal collinearity. The chromDraw graphical tool was developed as a user-friendly graphical tool for visualizing both linear and circular karyotypes based on the same input data matrix. The output graphics, saved in two different formats (EPS and SVG), can be easily imported to and modified in presentation and image-editing computer programs. The tool is freely distributed under GNU General Public License (GPL) and can be installed from Bioconductor or from the chromDraw home page.
Which R package is used for visualization of linear and circular karyotypes?
588f2de394c1512c50000001_001
{ "answer_start": [ 0 ], "text": [ "chromDraw" ] }
Selective disactivation of neurofibromin GAP activity in neurofibromatosis type 1. Neurofibromatosis type 1 (NF1) is a common familial tumour syndrome with multiple clinical features such as neurofibromas, café-au-lait spots (CLS), iris Lisch nodules, axillary freckling, optic glioma, specific bone lesions and an increased risk of malignant tumours. It is caused by a wide spectrum of mutations affecting the NF1 gene. Most mutations result in the loss of one allele at the DNA, mRNA or protein level and thus in the loss of any function of the gene product neurofibromin. The idea of the simultaneous loss of several different neurofibromin functions has been postulated to explain the pleiotropic effects of its loss. However, we have identified a novel missense mutation in a family with a classical multi-symptomatic NF1 phenotype, including a malignant schwannoma, that specifically abolishes the Ras-GTPase-activating function of neurofibromin. In this family, Arg1276 had mutated into proline. Based on complex biochemical studies as well as the analysis of the crystal structure of the GTPase-activating protein (GAP) domain of p120GAP in the presence of Ras, we unequivocally identified this amino acid as the arginine finger of the neurofibromin GAP-related domain (GRD)-the most essential catalytic element for RasGAP activity. Here, we present data demonstrating that the mutation R1276P, unlike previously reported missense mutations of the GRD region, does not impair the secondary and tertiary protein structure. It neither reduces the level of cellular neurofibromin nor influences its binding to Ras substantially, but it does completely disable GAP activity. Our findings provide direct evidence that failure of neurofibromin GAP activity is the critical element of NF1 pathogenesis. Thus, therapeutic approaches aimed at the reduction of Ras.GTP levels in neural crest-derived cells can be expected to relieve most of the NF1 symptoms.
Which is the gene mutated in type 1 neurofibromatosis?
5343fc1aaeec6fbd07000003_033
{ "answer_start": [ 109 ], "text": [ "NF1" ] }
Benzodiazepine intoxication treated with flumazenil (Anexate, RO 15-1788). The efficacy and safety of flumazenil were assessed in comparison to placebo in a double-blind randomised study of 31 adults intoxicated with benzodiazepines. The criteria of efficacy were the degree of sedation, and orientation in time and space. Patients who received flumazenil awoke within minutes but central depression returned partly one hour later, which reflects the short elimination half-life of the drug. Side effects were few and the results indicate that flumazenil is effective in the primary management of benzodiazepine overdose and in states where benzodiazepines have been taken with other drugs.
Which drug should be used as an antidote in benzodiazepine overdose?
514a0a57d24251bc05000051_048
{ "answer_start": [ 345 ], "text": [ "flumazenil" ] }
In-silico analysis of kallikrein gene expression in pancreatic and colon cancers. Human kallikreins are a cluster of 15 serine protease genes located in the chromosomal band 19q13.4, a non-randomly rearranged region in many solid tumors, including pancreatic cancer. We utilized the SAGE and EST databases of the Cancer Genome Anatomy Project to perform in-silico analysis of kallikrein gene expression in normal and cancerous pancreatic and colon tissues and cell lines using virtual Northern blotting (VNB), digital differential display (DDD) and X-profiler. At least two kallikreins, KLK6 and KLK10, are significantly up-regulated in pancreatic cancer. We probed 2 normal and 6 pancreatic cancer SAGE libraries with gene-specific tags for each of these kallikreins. KLK6 was found to be expressed in 5/6 cancer libraries and showed the most marked (5-fold) increase in average expression levels in cancer vs. normal. These data were verified by screening the EST databases, where all mRNA clones isolated were from cancerous libraries, with no clones detected in normal pancreatic tissues or cell lines. X-profiler comparison of two pools of normal and cancerous pancreatic libraries further verified the significant increase of KLK6 expression levels in pancreatic cancer. DDD data showed a 13-fold increase in KLK10 expression in pancreatic cancer. Three kallikrein genes, KLK6, 8 and 10 are overexpressed in colon cancer compared to normal colon, while one kallikrein, KLK1, is down-regulated. While no expression of KLK6 was detected in normal colon, KLK6-specific tags were detectable in 2 cancer libraries. Similar results were obtained by EST screening; no KLK6 clones were detected in any of the 28 normal libraries examined, while 10 KLK6 EST clones were found in colon adenocarcinoma. KLK10 was not detectable in normal colon. Gene-specific tags were, however, detectable with high density in colon cancer and 7 EST clones were found to be expressed in colon Adenocarcinoma.
How many tissue kallikrein genes are present in the human genome?
511a3573df1ebcce7d000018_008
{ "answer_start": [ 117 ], "text": [ "15" ] }
Expression and Structural Analyses of Human DNA Polymerase θ (POLQ). DNA polymerase theta (pol θ) is an evolutionarily conserved protein encoded by the POLQ gene in mammalian genomes. Pol θ is the defining enzyme for a pathway of DSB repair termed "alternative end-joining" (altEJ) or "theta-mediated end-joining." This pathway contributes significantly to the radiation resistance of mammalian cells. It also modulates accuracy in repair of breaks that occur at stalled DNA replication forks, during diversification steps of the mammalian immune system, during repair of CRISPR-Cas9, and in many DNA integration events. Pol θ is a potentially important clinical target, particularly for cancers deficient in other break repair strategies. The enzyme is uniquely able to mediate joining of single-stranded 3' ends. Because of these unusual biochemical properties and its therapeutic importance, it is essential to study structures of pol θ bound to DNA. However, challenges for expression and purification are presented by the large size of pol θ (2590 residues in humans) and unusual juxtaposition of domains (a helicase-like domain and distinct DNA polymerase, separated by a region predicted to be largely disordered). Here we summarize work on the expression and purification of the full-length protein, and then focus on the design, expression, and purification of an active C-terminal polymerase fragment. The generation of this active construct was nontrivial and time consuming. Almost all published biochemical work to date has been performed with this domain fragment. Strategies to obtain and improve crystals of a ternary pol θ complex (enzyme:DNA:nucleotide) are also presented, along with key elements of the structure.
Which human gene encode for DNA polymerase θ?
5aacd487fcf4565872000007_001
{ "answer_start": [ 69 ], "text": [ "DNA polymerase theta (pol θ) is an evolutionarily conserved protein encoded by the POLQ gene in mammalian genomes" ] }
Early discharge of patients with presumed opioid overdose: development of a clinical prediction rule. OBJECTIVE: To develop a clinical prediction rule to identify patients who can be safely discharged one hour after the administration of naloxone for presumed opioid overdose. METHODS: Patients who received naloxone for known or presumed opioid overdose were formally evaluated one hour later for multiple potential predictor variables. Patients were classified into two groups: those with adverse events within 24 hours and those without. Using classification and regression tree methodology, a decision rule was developed to predict safe discharge. RESULTS: Clinical findings from 573 patients allowed us to develop a clinical prediction rule with a sensitivity of 99% (95% CI = 96% to 100%) and a specificity of 40% (95% CI = 36% to 45%). Patients with presumed opioid overdose can be safely discharged one hour after naloxone administration if they: 1) can mobilize as usual; 2) have oxygen saturation on room air of >92%; 3) have a respiratory rate >10 breaths/min and <20 breaths/min; 4) have a temperature of >35.0 degrees C and <37.5 degrees C; 5) have a heart rate >50 beats/min and <100 beats/min; and 6) have a Glasgow Coma Scale score of 15. CONCLUSIONS: This prediction rule for safe early discharge of patients with presumed opioid overdose performs well in this derivation set but requires validation followed by confirmation of safe implementation.
Which medication should be administered when managing patients with suspected acute opioid overdose?
5149f494d24251bc0500004c_006
{ "answer_start": [ 308 ], "text": [ "naloxone" ] }
A proposed modification to Hy's law and Edish criteria in oncology clinical trials using aggregated historical data. PURPOSE: Identifying drug-induced liver injury is a critical task in drug development and postapproval real-world care. Severe liver injury is identified by the liver chemistry threshold of alanine aminotransferase (ALT) >3× upper limit of normal (ULN) and bilirubin >2× ULN, termed Hy's law by the Food and Drug Administration. These thresholds require discontinuation of the causative drug and are seldom exceeded in most patient populations. However, because maintenance of therapy is critical in the treatment of advanced cancer, customized thresholds may be useful in oncology patient populations, particularly for those with baseline liver chemistries elevations. METHODS: Liver chemistry data from 31 aggregated oncology clinical trials were modeled through a truncated robust multivariate outlier detection (TRMOD) method to develop the decision boundary or threshold for examining liver injury in oncology clinical trials. RESULTS: The boundary of TRMOD identified outliers with an ALT limit 5.0× ULN and total bilirubin limit 2.7× ULN. In addition, TRMOD was applied to the aggregated oncology data to examine fold-baseline ALT and total bilirubin, revealing limits of ALT 6.9× baseline and bilirubin 6.5× baseline. Similar ALT and bilirubin threshold limits were observed for oncology patients both with and without liver metastases. CONCLUSIONS: These higher liver chemistry thresholds examining fold-ULN and fold-baseline data may be valuable in identifying potential severe liver injury and detecting liver safety signals of clinical concern in oncology clinical trials and postapproval settings while helping to avoid premature discontinuation of curative therapy.
Hy's law measures failure for what organ?
58f4b25e70f9fc6f0f000011_010
{ "answer_start": [ 244 ], "text": [ "liver" ] }
Surviving competitive athletics with hypertrophic cardiomyopathy. Hypertrophic cardiomyopathy (HC) is probably the most common cause of sudden cardiac death in youthful athletes, and this diagnosis has represented a contraindication to continued participation in competitive sports. Less well appreciated is the fact that within the clinical spectrum of HC are patients who, despite having this disease, have been able to undertake particularly intensive and often extraordinary levels of training for sports competition over many years without dying suddenly. Fourteen such patients (13 men and 1 woman, aged 30 to 66 years [mean 43]) form the present study group. HC was initially identified at 24 to 57 years of age (mean 34), usually under fortuitous circumstances. Patients most often competed in distance running (including the marathon, 7), but also in swimming, triathalon, basketball, and football. The duration of training ranged from 6 to 22 years (mean 15) and 5 continue to train and compete actively. The magnitude of training, competition, and achievement was considerable in most patients; 12 of the 14 performed either at the national, collegiate or professional level in their sport, completed numerous marathon and triathalon events, or sustained particularly rigorous training regimens of > or = 50 miles/week. Echocardiographic studies demonstrated a left ventricular wall thickness of 18 to 28 mm (mean 20) in most patients (12 of 14) having a relatively localized pattern of ventricular septal hypertrophy. It is possible for some patients with HC to tolerate particularly intense athletic training and competition for many years, and even maintain high levels of achievement without incurring symptoms and disease progression or dying suddenly.(ABSTRACT TRUNCATED AT 250 WORDS)
Which is the most common cause of sudden cardiac death in young athletes?
530cf4e0c8a0b4a00c000006_011
{ "answer_start": [ 66 ], "text": [ "Hypertrophic cardiomyopathy" ] }
Identification of a novel inherited ALK variant M1199L in the WNT type of medulloblastoma. Rearrangements involving the ALK gene were identified in a variety of cancers, including paediatric tumour neuroblastoma where presence of ALK expression is also associated with adverse prognosis. Microarrays data indicate that ALK is expressed in another paediatric tumour - medulloblastoma. Therefore, we investigated if the ALK gene is mutated in medulloblastoma and performed simultaneously the molecular profiling of tumours. Tumours from sixty-four medulloblastoma patients were studied for detection of ALK alterations in exons 23 and 25 using Sanger method. The molecular subtypes of tumours were identified by detection of mutations in the CTNNB1 gene, monosomy 6 and by immunohistochemistry using a panel of representative antibodies. Among three ALK variants detected two resulted in intron variants (rs3738867, rs113866835) and the third one was a novel heterozygous variant c.3595A>T in exon 23 identified in the WNT type of tumour. It resulted in methionine to leucine substitution at codon position 1199 (M1199L) of the kinase domain of ALK protein. Results of analysis using three in silico algorithms confirmed the pathogenicity of this single nucleotide variation. The same gene alteration was detected in both patient and maternal peripheral blood leukocytes indicating an inherited type of the detected variant. Presence of ALK expression in tumour tissue was confirmed by immunohistochemistry. The tumour was diagnosed as classic medulloblastoma, however with visible areas of focal anaplastic features. The patient has been disease free for 6 years since diagnosis. This is the first evidence of an inherited ALK variant in the WNT type of medulloblastoma, what altogether with presence of ALK expression may point towards involvement of the ALK gene in this type of tumours.
What disease is the ALK tyrosine kinase associated with?
5a871a6861bb38fb24000009_015
{ "answer_start": [ 161 ], "text": [ "cancer" ] }
Molecular basis of albinism: mutations and polymorphisms of pigmentation genes associated with albinism. Albinism, caused by a deficiency of melanin pigment in the skin, hair, and eye (oculocutaneous albinism [OCA]), or primarily in the eye (ocular albinism [OA]), results from mutations in genes involved in the biosynthesis of melanin pigment. The lack of melanin pigment in the developing eye leads to fovea hypoplasia and abnormal routing of the optic nerves. These changes are responsible for the nystagmus, strabismus, and reduced visual acuity common to all types of albinism. Mutations in six genes have been reported to be responsible for different types of oculocutaneous and ocular albinism, including the tyrosinase gene (TYR) and OCA1 (MIM# 203100), the OCA2 gene and OCA2 (MIM# 203200), the tyrosinase-related protein-1 gene (TYRP1) and OCA3 (MIM# 203290), the HPS gene and Hermansky-Pudlak syndrome (MIM# 203300), the CHS gene (CHS1), and Chediak-Higashi syndrome (MIM# 214500), and the X-linked ocular albinism gene and OA1 (MIM#300500). The function of only two of the gene products is known tyrosinase and tyrosinase-related protein-1 both of which are enzymes in the melanin biosynthetic pathway. Continued mutational analysis coupled with function/structure studies should aid our understanding of the function of the remaining genes and their role in albinism. Mutation and polymorphism data on these genes are available from the International Albinism Center Albinism Database web site (http://www.cbc.umn.edu/tad).
Which mutated enzyme is responsible for oculocutaneous 1 (OCA1)-type albinism?
58cbb98c02b8c60953000034_037
{ "answer_start": [ 717 ], "text": [ "tyrosinase" ] }
Gene looping is conferred by activator-dependent interaction of transcription initiation and termination machineries. Gene looping juxtaposes the promoter and terminator regions of RNA polymerase II-transcribed genes in yeast and mammalian cells. Here we report an activator-dependent interaction of transcription initiation and termination factors during gene looping in budding yeast. Chromatin analysis revealed that MET16, INO1, and GAL1p-BUD3 are in a stable looped configuration during activated transcription. Looping was nearly abolished in the absence of transcription activators Met28, Ino2, and Gal4 of MET16, INO1, and GAL1p-BUD3 genes, respectively. The activator-independent increase in transcription was not accompanied by loop formation, thereby suggesting an essential role for activators in gene looping. The activators did not facilitate loop formation directly because they did not exhibit an interaction with the 3' end of the genes. Instead, activators physically interacted with the general transcription factor TFIIB when the genes were activated and in a looped configuration. TFIIB cross-linked to both the promoter and the terminator regions during the transcriptionally activated state of a gene. The presence of TFIIB on the terminator was dependent on the Rna15 component of CF1 3' end processing complex. Coimmunoprecipitation revealed a physical interaction of Rna15 with TFIIB. We propose that the activators facilitate gene looping through their interaction with TFIIB during transcriptional activation of genes.
Which protein mediates gene loop formation in the yeast S. cerevisiae?
58adc1ff9ef3c34033000006_008
{ "answer_start": [ 1497 ], "text": [ "TFIIB" ] }
Synergistic loss of prostate cancer cell viability by coinhibition of HDAC and PARP. UNLABELLED: Tumors with BRCA germline mutations are defective in repairing DNA double-strand breaks (DSB) through homologous recombination (HR) pathways, making them sensitive to PARP inhibitors (PARPi). However, BRCA germline mutations are rare in prostate cancer limiting the ability to therapeutically target these pathways. This study investigates whether histone deacetylase (HDAC) inhibitors (HDACi), reported to modulate DSB repair pathways in sporadic cancers, can downregulate DSB repair pathways and sensitize prostate cancer cells to PARPi. Prostate cancer cells cotreated with the HDAC inhibitor, suberoylanilide hydroxamic acid (SAHA) and the PARPi, olaparib, demonstrated a synergistic decrease in cell viability compared with single-agent treatment (combination index < 0.9), whereas normal prostatic cells did not. Similarly, clonogenicity was significantly decreased after cotreatment. Flow cytometric cell-cycle analysis and Annexin-V staining revealed significant apoptosis upon treatment with SAHA+olaparib. This coincided with increased DNA damage observed by immunofluorescence microscopy analysis of γH2AX foci, a marker of DSBs. In addition, immunoblot analysis showed a significant and persistent increase in nuclear γH2AX levels. Both SAHA and olaparib downregulated the expression of HR-related proteins, BRCA1 and RAD51, whereas SAHA + olaparib had an additive effect on RAD51. Silencing RAD51 sensitized prostate cancer cells to SAHA and olaparib alone. Collectively, cotreatment with HDACi and PARPi downregulated HR-related protein expression and concomitantly increased DNA damage, resulting in prostate cancer cell death. IMPLICATIONS: These findings provide a strong rationale for supporting the use of combined HDAC and PARP inhibition in treating advanced prostate cancer.
What is the target of the drug Olaparib?
54d649843706e89528000009_014
{ "answer_start": [ 741 ], "text": [ "PARP" ] }
Biosynthesis and intracellular targeting of the CLN3 protein defective in 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.
What is the effect of a defective CLN3 gene?
56b710f276d8bf8d13000003_010
{ "answer_start": [ 90 ], "text": [ "Batten disease" ] }
Treatment of suicidal and deliberate self-harming patients with borderline personality disorder using dialectical behavioral therapy: the patients' and the therapists' perceptions. The aim was to investigate patients and therapists perception of receiving and giving dialectical behavioral therapy (DBT). Ten deliberate self-harm patients with borderline personality disorder and four DBT-therapists were interviewed. The interviews were analyzed with qualitative content analysis. The patients unanimously regard the DBT-therapy as life saving and something that has given them a bearable life situation. The patients and the therapists are concordant on the effective components of the therapy: the understanding, respect, and confirmation in combination with the cognitive and behavioral skills. The experienced effectiveness of DBT is contrasted by the patient's pronouncedly negative experiences from psychiatric care before entering DBT.
Which personality disorder is treated using dialectical behavior therapy?
5a68f005b750ff4455000016_010
{ "answer_start": [ 64 ], "text": [ "borderline personality disorder" ] }
Pleiotropic effects of the melanocortin 1 receptor (MC1R) gene on human pigmentation. Variants of the melanocortin 1 receptor (MC1R) gene are common in individuals with red hair and fair skin, but the relative contribution to these pigmentary traits in heterozygotes, homozygotes and compound heterozygotes for variants at this locus from the multiple alleles present in Caucasian populations is unclear. We have investigated 174 individuals from 11 large kindreds with a preponderance of red hair and an additional 99 unrelated redheads, for MC1R variants and have confirmed that red hair is usually inherited as a recessive characteristic with the R151C, R160W, D294H, R142H, 86insA and 537insC alleles at this locus. The V60L variant, which is common in the population may act as a partially penetrant recessive allele. These individuals plus 167 randomly ascertained Caucasians demonstrate that heterozygotes for two alleles, R151C and 537insC, have a significantly elevated risk of red hair. The shade of red hair frequently differs in heterozygotes from that in homozygotes/compound heterozygotes and there is also evidence for a heterozygote effect on beard hair colour, skin type and freckling. The data provide evidence for a dosage effect of MC1R variants on hair as well as skin colour.
Which gene is responsible for red hair?
5ace19420340b9f05800000a_038
{ "answer_start": [ 127 ], "text": [ "MC1R" ] }
SEA0400, a novel Na+/Ca2+ exchanger inhibitor, reduces calcium overload induced by ischemia and reperfusion in mouse ventricular myocytes. Given the potential clinical benefit of inhibiting Na+/Ca2+ exchanger (NCX) activity during myocardial ischemia reperfusion (I/R), pharmacological approaches have been pursued to both inhibit and clarify the importance of this exchanger. SEA0400 was reported to have a potent NCX selectivity. Thus, we examined the effect of SEA0400 on NCX currents and I/R induced intracellular Ca2+ overload in mouse ventricular myocytes using patch clamp techniques and fluorescence measurements. Ischemia significantly inhibited inward and outward NCX current (from -0.04+/-0.01 nA to 0 nA at -100 mV; from 0.23+/-0.08 nA to 0.11+/-0.03 nA at +50 mV, n=7), Subsequent reperfusion not only restored the current rapidly but enhanced the current amplitude obviously, especially the outward currents (from 0.23+/-0.08 nA to 0.49+/-0.12 nA at +50 mV, n=7). [Ca2+]i, expressed as the ratio of Fura-2 fluorescence intensity, increased to 138+/-7% (P<0.01) during ischemia and to 210+/-11% (P<0.01) after reperfusion. The change of NCX current and the increase of [Ca2+]i during I/R can be blocked by SEA0400 in a dose-dependent manner with an EC50 value of 31 nM and 28 nM for the inward and outward NCX current, respectively. The results suggested that SEA0400 is a potent NCX inhibitor, which can protect mouse cardiac myocytes from Ca2+ overload during I/R injuries.
The small molecule SEA0400 is an inhibitor of which ion antiporter/exchanger?
5506c3e38e1671127b00000a_042
{ "answer_start": [ 1393 ], "text": [ "NCX" ] }
Functional centromeres determine the activation time of pericentric origins of DNA replication in Saccharomyces cerevisiae. The centromeric regions of all Saccharomyces cerevisiae chromosomes are found in early replicating domains, a property conserved among centromeres in fungi and some higher eukaryotes. Surprisingly, little is known about the biological significance or the mechanism of early centromere replication; however, the extensive conservation suggests that it is important for chromosome maintenance. Do centromeres ensure their early replication by promoting early activation of nearby origins, or have they migrated over evolutionary time to reside in early replicating regions? In Candida albicans, a neocentromere contains an early firing origin, supporting the first hypothesis but not addressing whether the new origin is intrinsically early firing or whether the centromere influences replication time. Because the activation time of individual origins is not an intrinsic property of S. cerevisiae origins, but is influenced by surrounding sequences, we sought to test the hypothesis that centromeres influence replication time by moving a centromere to a late replication domain. We used a modified Meselson-Stahl density transfer assay to measure the kinetics of replication for regions of chromosome XIV in which either the functional centromere or a point-mutated version had been moved near origins that reside in a late replication region. We show that a functional centromere acts in cis over a distance as great as 19 kb to advance the initiation time of origins. Our results constitute a direct link between establishment of the kinetochore and the replication initiation machinery, and suggest that the proposed higher-order structure of the pericentric chromatin influences replication initiation.
Do origins of replication close to yeast centromeres fire early or late?
58eb99f3eda5a57672000009_002
{ "answer_start": [ 575 ], "text": [ "early" ] }
Diagnosis of pneumoperitoneum on supine abdominal radiographs. A blinded, retrospective study was performed to determine the value of supine abdominal radiographs in diagnosing pneumoperitoneum. Supine films from 44 cases of pneumoperitoneum were randomly interspersed among supine films from 87 control subjects without free air, and the films were reviewed for the presence or absence of various signs of pneumoperitoneum, including Rigler's sign (gas on both sides of the bowel wall), the falciform ligament sign (gas outlining the falciform ligament), the football sign (gas outlining the peritoneal cavity), the inverted-V sign (gas outlining the medial umbilical folds), and the right-upper-quadrant gas sign (localized gas in the right upper quadrant). One or more of these signs were present in 26 cases (59%) of pneumoperitoneum, including the right-upper-quadrant gas sign in 18 cases (41%), Rigler's sign in 14 cases (32%), and the falciform ligament and football signs in one case each (2%). Unfortunately, there were frequent errors in the interpretation of the right-upper-quadrant gas sign and Rigler's sign, with a total of 11 false-positive cases (13%). Further analysis of the true-positive right-upper-quadrant gas signs showed that these gas collections were always triangular or linear with an inferolateral to superomedial orientation and, if triangular, a concave superolateral border. In the true-positive Rigler's signs, the bowel wall thickness ranged from 1 to 8 mm, whereas the false positives all had a bowel wall thickness of 1 mm or less. Proper interpretation of the various signs of pneumoperitoneum on supine films should lead to more accurate diagnosis of this condition.
Falciform ligament sign is characteristic to which disease?
5a72329e2dc08e987e000006_003
{ "answer_start": [ 407 ], "text": [ "pneumoperitoneum" ] }
Aberrant functional network recruitment of posterior parietal cortex in Turner syndrome. Turner syndrome is a genetic disorder caused by the complete or partial absence of an X chromosome in affected women. Individuals with TS show characteristic difficulties with executive functions, visual-spatial and mathematical cognition, with relatively intact verbal skills, and congruent abnormalities in structural development of the posterior parietal cortex (PPC). The functionally heterogeneous PPC has recently been investigated using connectivity-based clustering methods, which sub-divide a given region into clusters of voxels showing similar structural or functional connectivity to other brain regions. In the present study, we extended this method to compare connectivity-based clustering between groups and investigate whether functional networks differentially recruit the PPC in TS. To this end, we parcellated the PPC into sub-regions based on temporal correlations with other regions of the brain. fMRI data were collected from 15 girls with TS and 14 typically developing (TD) girls, aged 7-14, while they performed a visual-spatial task. Temporal correlations between voxels in the PPC and a set of seed regions were calculated, and the PPC divided into clusters of voxels showing similar connectivity. It was found that in general the PPC parcellates similarly in TS and TD girls, but that regions in bilateral inferior parietal lobules, and posterior right superior parietal lobule, were reliably recruited by different networks in TS relative to TD participants. These regions showed weaker correlation in TS with a set of regions involved in visual processing. These results suggest that abnormal development of visuospatial functional networks in TS may relate to the well documented cognitive difficulties in this disorder.
What chromosome is affected in Turner's syndrome?
58bca2f302b8c6095300000c_002
{ "answer_start": [ 175 ], "text": [ "X" ] }
CancerSubtypes: an R/Bioconductor package for molecular cancer subtype identification, validation and visualization. Summary: Identifying molecular cancer subtypes from multi-omics data is an important step in the personalized medicine. We introduce CancerSubtypes, an R package for identifying cancer subtypes using multi-omics data, including gene expression, miRNA expression and DNA methylation data. CancerSubtypes integrates four main computational methods which are highly cited for cancer subtype identification and provides a standardized framework for data pre-processing, feature selection, and result follow-up analyses, including results computing, biology validation and visualization. The input and output of each step in the framework are packaged in the same data format, making it convenience to compare different methods. The package is useful for inferring cancer subtypes from an input genomic dataset, comparing the predictions from different well-known methods and testing new subtype discovery methods, as shown with different application scenarios in the Supplementary Material. Availability and implementation: The package is implemented in R and available under GPL-2 license from the Bioconductor website (http://bioconductor.org/packages/CancerSubtypes/). Contact: [email protected] or [email protected]. Supplementary information: Supplementary data are available at Bioinformatics online.
Which R/Bioconductor package has been developed for cancer subtype identification?
5a6e3155b750ff445500003f_007
{ "answer_start": [ 405 ], "text": [ "CancerSubtypes" ] }
LHCII is an antenna of both photosystems after long-term acclimation. LHCII, the most abundant membrane protein on earth, is the major light-harvesting complex of plants. It is generally accepted that LHCII is associated with Photosystem II and only as a short-term response to overexcitation of PSII a subset moves to Photosystem I, triggered by its phosphorylation (state1 to state2 transition). However, here we show that in most natural light conditions LHCII serves as an antenna of both Photosystem I and Photosystem II and it is quantitatively demonstrated that this is required to achieve excitation balance between the two photosystems. This allows for acclimation to different light intensities simply by regulating the expression of LHCII genes only. It is demonstrated that indeed the amount of LHCII that is bound to both photosystems decreases when growth light intensity increases and vice versa. Finally, time-resolved fluorescence measurements on the photosynthetic thylakoid membranes show that LHCII is even a more efficient light harvester when associated with Photosystem I than with Photosystem II.
Which is the most abundant membrane protein on Earth?
5519a7d5622b194345000015_003
{ "answer_start": [ 70 ], "text": [ "LHCII" ] }
The radiology of pulmonary cryptococcosis in a tertiary medical center. Pulmonary cryptococcal infections occur in both immunocompetent and immunocompromised individuals, with a reported increased incidence of diffuse pulmonary disease in acquired immune deficiency syndrome (AIDS) patients. The authors observed no differences in the radiographic appearances of pulmonary cryptococcal disease between human immunodeficiency virus (HIV) patients and other immunocompromised individuals. Chest computed tomography (CT) contributes to a more comprehensive understanding of pulmonary cryptococcal infections.
Which is the main reason for the increase in the incidence of cryptococcal disease?
5ace37d50340b9f058000011_012
{ "answer_start": [ 432 ], "text": [ "HIV" ] }
Mutations of the human tyrosinase gene associated with tyrosinase related oculocutaneous albinism (OCA1). Mutations in brief no. 204. Online. Mutations in the human tyrosinase gene produce tyrosinase-related oculocutaneous albinism (OCA1, MIM #203100). Tyrosinase is a copper containing enzyme and is responsible for catalyzing the rate limiting step in melanin biosynthesis, the hydroxylation of tyrosine to dopaquinone. We report 13 new mutations in the tyrosinase gene associated with OCA1A (without pigment) and OCA1B (with pigment) including 9 missense mutations (H19Q, R521, R77C, G97R, C289R, L312V, P313R, F340L and H404P), two nonsense mutations (W80X and R116X) and two frameshift mutations (53delG and 223 delG). Our previous work has defined clusters of missense mutations that appear to represent functional domains of the enzyme, and three of the missense mutations fall into these clusters including two (F340L and H404P) that flank the copper B bindng site and the missense mutation R52I that is located in the amino terminal end cluster of the protein. The G97R missense mutation is the first identified within the epidermal growth factor (EGF)-like sequence and the H19Q missense mutation alters the cleavage site of the signal peptide sequence. Mutational analysis can provide a definitive diagnosis of the type of OCA as well as help structure/function analysis.
Which mutated enzyme is responsible for oculocutaneous 1 (OCA1)-type albinism?
58cbb98c02b8c60953000034_017
{ "answer_start": [ 23 ], "text": [ "tyrosinase" ] }
Mechanisms of activation of NADPH oxidases. The members of the NOX family of enzymes are expressed in a variety of tissues and serve a number of functions. There is a high level of conservation of primary protein sequence, as well as functional features, although specialized responses are beginning to emerge. In this context, our data demonstrate that the NOX1 cytoplasmic domains interact efficiently with the cytoplasmic subunits of the phagocyte NADPH oxidase and identify the second cytoplasmic loop of NOX electron transporters as a crucial domain for enzyme function. Studies of cytosolic co-factors showed that the C-terminal cytoplasmic domain of NOX1 was absolutely required for activation with NOXO1 and NOXA1 and that this activity required interaction of the putative NADPH-binding region of this domain with NOXA1. Finally, we have provided the first example of how alternative splicing of a NOX co-factor may be involved in the regulation of NADPH oxidase function.
Which NADPH oxidase family member requires interaction with NOXO1 for function?
58a5a51060087bc10a000021_030
{ "answer_start": [ 657 ], "text": [ "NOX1" ] }
Phenotypic spectrum of patients with PLA2G6 mutation and PARK14-linked parkinsonism. BACKGROUND: PLA2G6 is the causative gene for infantile neuroaxonal dystrophy, neurodegeneration associated with brain iron accumulation, and Karak syndrome. Based on previous reports, patients with PLA2G6 mutations could show axonal dystrophy, dystonia, dementia, and cerebellar signs. Recently, PLA2G6 was also reported as the causative gene for early-onset PARK14-linked dystonia-parkinsonism. METHODS: To clarify the role of PLA2G6 mutation in parkinsonism, we conducted mutation analysis in 29 selected patients with very early-onset ( < 30, mean 21.2 ± 8.4 years, ± SD) parkinsonism. These patients had other clinical features (e.g., mental retardation/dementia [14/29], psychosis [15/29], dystonia [11/29], and hyperreflexia [11/29]). RESULTS: Two novel compound heterozygous PLA2G6 mutations were detected (patient A: p.F72L/p.R635Q; patients B1 and B2: p.Q452X/p.R635Q). All 3 patients had early-onset l-dopa-responsive parkinsonism with dementia and frontotemporal lobar atrophy. Disease progression was relatively rapid. SPECT in patient B1 showed frontotemporal lobar hypoperfusion. MRI in patient A showed iron accumulation in the substantia nigra and striatum. CONCLUSIONS: Although the clinical presentation of PLA2G6-associated neurodegeneration was reported to be homogeneous, our findings suggest patients with PLA2G6 mutation could show heterogeneous phenotype such as dystonia-parkinsonism, dementia, frontotemporal atrophy/hypoperfusion, with or without brain iron accumulation. Based on the clinical heterogeneity, the functional roles of PLA2G6 and the roles of PLA2G6 variants including single heterozygous mutations should be further elucidated in patients with atypical parkinsonism, dementia, or Parkinson disease. PLA2G6 mutations should be considered in patients with early-onset l-dopa-responsive parkinsonism and dementia with frontotemporal lobar atrophy.
Which gene is mutated in the Karak syndrome?
588f9950ed9bbee70d000002_004
{ "answer_start": [ 97 ], "text": [ "PLA2G6" ] }
First trimester maternal serum PAPP-A and free β-HCG levels in hyperemesis gravidarum. OBJECTIVE: To evaluate whether hyperemesis gravidarum (HG) affects first-trimester maternal serum PAPP-A and free β-hCG levels. METHOD: An observational study was conducted in 115 cases of HG and 110 control pregnancies who attended the first-trimester prenatal screening program between January 2006 and July 2010. RESULTS: Maternal serum TSH levels were lower and free T4, and transaminases (ALT, AST) levels were higher in pregnancies complicated with HG compared with controls (p < 0.05 for all). In HG cases, median values of maternal serum PAPP-A were significantly higher with respect to normal pregnancies (1.2 vs 1.0 MoM; p = 0.009). Similarly, median values of free β-hCG were 1.3 MoM in HG pregnancies and 1.0 MoM in controls (p = 0.006). Multivariate analysis revealed that PAPP-A and hCG were independently associated with HG after controlling for TSH, free T4, AST, and ALT. CONCLUSION: HG is associated with elevated levels of PAPP-A and free β-hCG, and such changes are independent of serum indicators of thyroid and liver function.
Which protein is associated with hyperemesis gravidarum during pregrancy?
58da1aa08acda34529000012_003
{ "answer_start": [ 1047 ], "text": [ "hCG" ] }
Antigenotoxic effects of p53 on spontaneous and ultraviolet light B--induced deletions in the epidermis of gpt delta transgenic mice. Tumor development in the skin may be a multistep process where multiple genetic alterations occur successively. The p53 gene is involved in genome stability and thus is referred to as "the guardian of the genome." To better understand the antigenotoxic effects of p53 in ultraviolet light B (UVB)-induced mutagenesis, mutations were measured in the epidermis of UVB-irradiated p53(+/+) and p53(-/-) gpt delta mice. In the mouse model, point mutations and deletions are separately identified by the gpt and Spi(-) assays, respectively. The mice were exposed to UVB at single doses of 0.5, 1.0, or 2.0 kJ/m(2) . The mutant frequencies (MFs) were determined 4 weeks after the irradiation. All doses of UVB irradiation enhanced gpt MFs by about 10 times than that of unirradiated mice. There were no significant differences in gpt MFs and the mutation spectra between p53(+/+) and p53(-/-) mice. The predominant mutations induced by UVB irradiation were G:C to A:T transitions at dipyrimidines. In contrast, in unirradiated p53(-/-) mice, the frequencies of Spi(-) large deletions of more than 1 kb and complex-type deletions with rearrangements were significantly higher than those of the Spi(-) large deletions in p53(+/+) counterparts. The specific Spi(-) mutation frequency of more than 1 kb deletions and complex types increased in a dose-dependent manner in the p53(+/+) mice. However, no increase of such large deletions was observed in irradiated p53(-/-) mice. These results suggest that the antigenotoxic effects of p53 may be specific to deletions and complex-type mutations induced by double-strand breaks in DNA.
Which tumor suppressor is referred to as "the guardian of the genome"?
55421ee7ccca0ce74b000002_037
{ "answer_start": [ 398 ], "text": [ "p53" ] }
Twiddler's syndrome in a patient with a deep brain stimulation device for generalized dystonia. Deep brain stimulation (DBS) is the technique of neurostimulation of deep brain structures for the treatment of conditions such as essential tremor, dystonia, Parkinson's disease and chronic pain syndromes. The procedure uses implanted deep brain stimulation electrodes connected to extension leads and an implantable pulse generator (IPG). Hardware failure related to the DBS procedure is not infrequent, and includes electrode migration and disconnection. We describe a patient who received bilateral globus pallidus internus DBS for dystonia with initially good clinical response, but the device eventually failed. Radiographs showed multiple twisting of the extension leads with disconnection from the brain electrodes and a diagnosis of Twiddler's syndrome was made. Twiddler's syndrome was first described in patients with cardiac pacemakers. Patients with mental disability, elderly and obese patients are at increased risk. Twiddler's syndrome should be suspected whenever there is a failure of the DBS device to relieve symptoms previously responsive to stimulation. Surgical correction is usually required.
Neurostimulation of which nucleus is used for treatment of dystonia?
54fc99f36ad7dcbc12000004_002
{ "answer_start": [ 599 ], "text": [ "globus pallidus internus" ] }
Betrixaban compared with warfarin in patients with atrial fibrillation: results of a phase 2, randomized, dose-ranging study (Explore-Xa). AIMS: Patients with atrial fibrillation (AF) are at increased risk of stroke. Betrixaban is a novel oral factor Xa inhibitor administered once daily, mostly excreted unchanged in the bile and with low (17%) renal excretion. METHODS AND RESULTS: Patients with AF and more than one risk factor for stroke were randomized to one of three blinded doses of betrixaban (40, 60, or 80 mg once daily) or unblinded warfarin, adjusted to an international normalized ratio of 2.0-3.0. The primary outcome was major or clinically relevant non-major bleeding. The mean follow-up was 147 days. Among 508 patients randomized, the mean CHADS2 score was 2.2; 87% of patients had previously received vitamin K antagonist therapy. The time in therapeutic range on warfarin was 63.4%. There were one, five, five, and seven patients with a primary outcome on betrixaban 40, 60, 80 mg daily, or warfarin, respectively. The rate of the primary outcome was lowest on betrixaban 40 mg (hazard ratio compared with warfarin = 0.14, exact stratified log-rank P-value 0.04, unadjusted for multiple testing). Rates of the primary outcome with betrixaban 60 or 80 mg were more similar to those of wafarin. Two ischaemic strokes occurred, one each on betrixaban 60 and 80 mg daily. There were two vascular deaths, one each on betrixaban 40 mg and warfarin. Betrixaban was associated with higher rates of diarrhoea than warfarin. CONCLUSION: Betrixaban was well tolerated and had similar or lower rates of bleeding compared with well-controlled warfarin in patients with AF at risk for stroke.
Which clotting factor is inhibited by betrixaban?
55200c606b348bb82c000013_145
{ "answer_start": [ 222 ], "text": [ "xa" ] }
Ataxin-3 protein modification as a treatment strategy for spinocerebellar ataxia type 3: removal of the CAG containing exon. Spinocerebellar ataxia type 3 is caused by a polyglutamine expansion in the ataxin-3 protein, resulting in gain of toxic function of the mutant protein. The expanded glutamine stretch in the protein is the result of a CAG triplet repeat expansion in the penultimate exon of the ATXN3 gene. Several gene silencing approaches to reduce mutant ataxin-3 toxicity in this disease aim to lower ataxin-3 protein levels, but since this protein is involved in deubiquitination and proteasomal protein degradation, its long-term silencing might not be desirable. Here, we propose a novel protein modification approach to reduce mutant ataxin-3 toxicity by removing the toxic polyglutamine repeat from the ataxin-3 protein through antisense oligonucleotide-mediated exon skipping while maintaining important wild type functions of the protein. In vitro studies showed that exon skipping did not negatively impact the ubiquitin binding capacity of ataxin-3. Our in vivo studies showed no toxic properties of the novel truncated ataxin-3 protein. These results suggest that exon skipping may be a novel therapeutic approach to reduce polyglutamine-induced toxicity in spinocerebellar ataxia type 3.
Which is the protein implicated in Spinocerebellar ataxia type 3?
57138eb21174fb175500000a_006
{ "answer_start": [ 201 ], "text": [ "ataxin-3" ] }
Novel mutation in SLC9A6 gene in a patient with Christianson syndrome and retinitis pigmentosum. Mutations in the SLC9A6 gene cause Christianson syndrome in boys. This X-linked syndrome is characterized by profound mental retardation with autistic behavior, microcephaly, epilepsy, ophthalmoplegia, and ataxia. Progressive cerebellar atrophy with motor regression is a remarkable feature in some patients. We report on a 22year-old male patient with Christianson syndrome carrying the novel p.Gln306X mutation. The infantile phenotype suggested pervasive developmental disorder, then profound mental retardation ensued. In later childhood, progressive cerebellar atrophy was diagnosed on serial brain MRIs and motor regression occurred. Furthermore, ophthalmological evaluations showed a retinitis pigmentosum previously unreported in this condition. We conclude that the natural history of the disease in this patient tends to confirm the degenerative nature of Christianson syndrome, and that retinal degeneration may be part of the condition. Before the onset of degeneration, the syndromic association of severe mental retardation, autistic behavior, external ophthalmoplegia, and facial dysmorphism in male patients is a clue to the diagnosis.
Mutation of which gene is implicated in the Christianson syndrome?
5895bc397d9090f35300000b_010
{ "answer_start": [ 114 ], "text": [ "SLC9A6" ] }
Mutations of the human tyrosinase gene associated with tyrosinase related oculocutaneous albinism (OCA1). Mutations in brief no. 204. Online. Mutations in the human tyrosinase gene produce tyrosinase-related oculocutaneous albinism (OCA1, MIM #203100). Tyrosinase is a copper containing enzyme and is responsible for catalyzing the rate limiting step in melanin biosynthesis, the hydroxylation of tyrosine to dopaquinone. We report 13 new mutations in the tyrosinase gene associated with OCA1A (without pigment) and OCA1B (with pigment) including 9 missense mutations (H19Q, R521, R77C, G97R, C289R, L312V, P313R, F340L and H404P), two nonsense mutations (W80X and R116X) and two frameshift mutations (53delG and 223 delG). Our previous work has defined clusters of missense mutations that appear to represent functional domains of the enzyme, and three of the missense mutations fall into these clusters including two (F340L and H404P) that flank the copper B bindng site and the missense mutation R52I that is located in the amino terminal end cluster of the protein. The G97R missense mutation is the first identified within the epidermal growth factor (EGF)-like sequence and the H19Q missense mutation alters the cleavage site of the signal peptide sequence. Mutational analysis can provide a definitive diagnosis of the type of OCA as well as help structure/function analysis.
Which mutated enzyme is responsible for oculocutaneous 1 (OCA1)-type albinism?
58cbb98c02b8c60953000034_029
{ "answer_start": [ 456 ], "text": [ "tyr" ] }
A frameshift mutation in the LYST gene is responsible for the Aleutian color and the associated Chédiak-Higashi syndrome in American mink. One of the colors of mink is Aleutian (aa)-a specific gun-metal gray pigmentation of the fur-commonly used in combination with other color loci to generate popular colors such as Violet (aammpp) and Sapphire (aapp). The Aleutian color allele is a manifestation of mink Chédiak-Higashi syndrome (CHS), which has been described in humans and several other species. As with forms of CHS in other species, we report that the mink CHS is linked to the lysosomal trafficking regulator ( LYST ) gene. Furthermore, we have identified a base deletion (c.9468delC) in exon 40 of LYST, which causes a frameshift and virtually terminates the LYST product prematurely (p.Leu3156Phefs*37). We investigated the blood parameters of three wild-type mink and three CHS mink. No difference in the platelet number between the two groups was observed, but an accumulation of platelets between the groups appears different when collagen is used as a coagulant. Microscopic analysis of peripheral blood indicates giant inclusions in the neutrophils of the Aleutian mink types. Molecular findings at the LYST locus enable the development of genetic tests for analyzing the color selection in American mink.
Which mutated gene causes the Chédiak–Higashi Syndrome?
58cbd0d502b8c60953000035_001
{ "answer_start": [ 29 ], "text": [ "LYST gene" ] }
Chest pain in a young patient: an unusual complication of Epstein-Barr virus. A 29-year-old man presented with sudden left-sided pleuritic chest pain on a background of sore throat during the preceding week. On examination he had tender cervical lymphadenopathy, he was tachycardic and had a 24 mm Hg blood pressure difference between the left and right arms. Bloods revealed deranged liver function tests and a lymphocytosis. His D-dimer was raised, hence he was treated for presumed pulmonary embolism before imaging was available. Monospot test was positive. He subsequently had both a CT pulmonary angiogram and a CT angiogram of the aorta to exclude pulmonary embolism and aortic dissection. The CT revealed splenomegaly with a large subdiaphragmatic haematoma secondary to splenic rupture. This had likely caused referred pain through diaphragmatic irritation. He was taken to theatre for urgent splenectomy. The unifying diagnosis was infectious mononucleosis complicated by spontaneous splenic rupture secondary to Epstein-Barr virus infection.
Which virus can be diagnosed with the monospot test?
5a690487b750ff445500001f_004
{ "answer_start": [ 1023 ], "text": [ "Epstein-Barr virus" ] }
BRCA1-associated epigenetic regulation of p73 mediates an effector pathway for chemosensitivity in ovarian carcinoma. The majority of tumors arising in BRCA1 mutation carriers exhibit inactivation of p53, a key effector of cell death after DNA damage. Despite the loss of p53, BRCA1-deficient tumor cells exhibit increased sensitivity to cisplatin, and patients with BRCA1-associated ovarian carcinomas experience improved outcomes with platinum-based chemotherapy compared with sporadic cases. Although it is known that chemosensitivity in BRCA1-associated cancers is associated with unrepaired DNA damage, the specific effector pathway mediating the cellular response to platinum-induced damage in these tumors is poorly understood. Here, we show that the p53-related gene p73, encoding a proapoptotic protein that is linked to chemosensitivity in many settings, is upregulated through a novel epigenetic mechanism in both human and murine models of BRCA1-associated ovarian carcinoma. BRCA1-deficient ovarian carcinoma cells exhibit hypermethylation within a p73 regulatory region, which includes the binding site for the p73 transcriptional repressor ZEB1, leading to the abrogation of ZEB1 binding and increased expression of transactivating p73 isoforms (TAp73). Cisplatin chemotherapy induces TAp73 target genes specifically in BRCA1-deficient cells, and knockdown of TAp73 in these cells causes chemoresistance while having little or no effect on BRCA1-expressing tumor cells. In primary ovarian carcinomas, ZEB1 binding site methylation and TAp73 expression correlate with BRCA1 status and with clinical response. Together, these findings uncover a novel regulatory mechanism that supports the contribution of TAp73 as an important mediator of the response to platinum chemotherapy in a subset of ovarian carcinomas. TAp73 might represent a response predictor and potential therapeutic target for enhancing chemosensitivity in this disease.
How many TAp73 isoforms have been identified in humans?
5173bdb38ed59a060a000020_033
{ "answer_start": [ 1063 ], "text": [ "7" ] }
Endoplasmic reticulum-specific BH3-only protein BNIP1 induces mitochondrial fragmentation in a Bcl-2- and Drp1-dependent manner. Bcl-2/adenovirus E1B 19-kDa interacting protein 1 (BNIP1), which is predominantly localized to the endoplasmic reticulum (ER), is a pro-apoptotic Bcl-2 homology domain 3 (BH3)-only protein. Here, we show that the expression of BNIP1 induced not only a highly interconnected ER network but also mitochondrial fragmentation in a BH3 domain-dependent manner. Functional analysis demonstrated that BNIP1 expression increased dynamin-related protein 1 (Drp1) expression followed by the mitochondrial translocation of Drp1 and subsequent mitochondrial fission. Both BNIP1-induced mitochondrial fission and the translocation of Drp1 were abrogated by Bcl-2 overexpression. These results collectively indicate that ER-specific BNIP1 plays an important role in mitochondrial dynamics by modulating the mitochondrial fission protein Drp1 in a BH3 domain-dependent fashion.
What is the functional role of the protein Drp1?
5717dbfe7de986d80d000001_015
{ "answer_start": [ 661 ], "text": [ "mitochondrial fission" ] }
Towards effective immunotherapy of myeloma: enhanced elimination of myeloma cells by combination of lenalidomide with the human CD38 monoclonal antibody daratumumab. BACKGROUND: In our efforts to develop novel effective treatment regimens for multiple myeloma we evaluated the potential benefits of combining the immunomodulatory drug lenalidomide with daratumumab. Daratumumab is a novel human CD38 monoclonal antibody which kills CD38+ multiple myeloma cells via antibody-dependent cell-mediated cytotoxicity, complement-dependent cytotoxicity and apoptosis. DESIGN AND METHODS: To explore the effect of lenalidomide combined with daratumumab, we first carried out standard antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity assays in which the CD38+ multiple myeloma cell line UM-9 and primary multiple myeloma cells isolated from patients were used as target cells. We also tested the effect of lenalidomide on daratumumab-dependent cell-mediated-cytotoxicity and complement-dependent cytotoxicity of multiple myeloma cells directly in the bone marrow mononuclear cells of multiple myeloma patients. Finally, we determined the daratumumab-dependent cell-mediated cytotoxicity using peripheral blood mononuclear cells of multiple myeloma patients receiving lenalidomide treatment. RESULTS: Daratumumab-dependent cell-mediated cytotoxicity of purified primary multiple myeloma cells, as well as of the UM-9 cell line, was significantly augmented by lenalidomide pre-treatment of the effector cells derived from peripheral blood mononuclear cells from healthy individuals. More importantly, we demonstrated a clear synergy between lenalidomide and daratumumab-induced antibody-dependent cell-mediated cytotoxicity directly in the bone marrow mononuclear cells of multiple myeloma patients, indicating that lenalidomide can also potentiate the daratumumab-dependent lysis of myeloma cells by activating the autologous effector cells within the natural environment of malignant cells. Finally, daratumumab-dependent cell-mediated cytotoxicity was significantly up-regulated in peripheral blood mononuclear cells derived from 3 multiple myeloma patients during lenalidomide treatment. CONCLUSIONS: Our results indicate that powerful and complementary effects may be achieved by combining lenalidomide and daratumumab in the clinical management of multiple myeloma.
Which molecule is targeted by Daratumumab?
56c04412ef6e39474100001b_035
{ "answer_start": [ 780 ], "text": [ "CD38" ] }
Molecular and cellular bases of chronic myeloid leukemia. Chronic myeloid leukemia (CML) is a myeloproliferative disease characterized by the overproduction of granulocytes, which leads to high white blood cell counts and splenomegaly in patients. Based on clinical symptoms and laboratory findings, CML is classified into three clinical phases, often starting with a chronic phase, progressing to an accelerated phase and ultimately ending in a terminal phase called blast crisis. Blast crisis phase of CML is clinically similar to an acute leukemia; in particular, B-cell acute lymphoblastic leukemia (B-ALL) is a severe form of acute leukemia in blast crisis, and there is no effective therapy for it yet. CML is induced by the BCR-ABL oncogene, whose gene product is a BCR-ABL tyrosine kinase. Currently, inhibition of BCR-ABL kinase activity by its kinase inhibitor such as imatinib mesylate (Gleevec) is a major therapeutic strategy for CML. However, the inability of BCR-ABL kinase inhibitors to completely kill leukemia stem cells (LSCs) indicates that these kinase inhibitors are unlikely to cure CML. In addition, drug resistance due to the development of BCRABL mutations occurs before and during treatment of CML with kinase inhibitors. A critical issue to resolve this problem is to fully understand the biology of LSCs, and to identify key genes that play significant roles in survival and self-renewal of LSCs. In this review, we will focus on LSCs in CML by summarizing and discussing available experimental results, including the original studies from our own laboratory.
What tyrosine kinase, involved in a Philadelphia- chromosome positive chronic myelogenous leukemia, is the target of Imatinib (Gleevec)?
5324a8ac9b2d7acc7e000018_031
{ "answer_start": [ 773 ], "text": [ "BCR-ABL" ] }
Specific antidotes in development for reversal of novel anticoagulants: a review. In the last decade, several direct oral anticoagulants (DOAC; dabigatran, rivaroxaban, apixaban, edoxaban) have been marketed for prophylaxis and/or treatment of thromboembolism without having specific antidotes available for their reversal. Current management of bleeding associated to DOAC includes the removal of all antithrombotic medications and supportive care. Non-specific procoagulant agents (prothrombin complex concentrates and activated factor VIIa) have been used in case of serious bleeding. Currently, some specific antidotes for the DOAC are under development. Idarucizumab (BI 655075; Boehringer Ingelheim) is a fragment of an antibody (Fab), which is a specific antidote to the oral direct thrombin inhibitor dabigatran. Andexanet alfa (r-Antidote, PRT064445; Portola Pharmaceuticals) is a truncated form of enzymatically inactive factor Xa, which binds and reverses the anticoagulant action of the factor Xa inhibitors (e.g.: rivaroxaban, apixaban and edoxaban). Aripazine (PER-977, ciraparantag; Perosphere Inc.) is a synthetic small molecule (~500 Da) that reverses oral dabigatran, apixaban, rivaroxaban, as well as subcutaneous fondaparinux and LMWH in vivo. These antidotes could provide an alternative for management of life-threatening bleeding events occurring with the above-mentioned anticoagulants. In addition, the specific antidote anivamersen (RB007; Regado Biosciences Inc.) is an RNA aptamer in clinical development to reverse the anticoagulant effect of the parenteral factor IXa inhibitor pegnivacogin, which is also in development. This anticoagulant-antidote pair may provide an alternative in situations in which a fast onset and offset of anticoagulation is needed, like in patients undergoing cardiac surgery with extracorporeal circulation, as an alternative to the heparin/protamine pair. This patent review includes a description of the pharmacological characteristics of the novel specific antidotes, the available results from completed non-clinical and clinical studies and the description of ongoing clinical trials with the new compounds.
Andexanet Alfa is an antidote of which clotting factor inhibitors?
5880b073c872c95565000003_064
{ "answer_start": [ 999 ], "text": [ "factor Xa" ] }
Effect of dural detachment on long-term tumor control for meningiomas treated using Simpson grade IV resection. OBJECT: Meningiomas treated by subtotal or partial resection are associated with significantly shorter recurrence-free survival than those treated by gross-total resection. The Simpson grading system classifies incomplete resections into a single category, namely Simpson Grade IV, with wide variations in the volume and location of residual tumors, making it complicated to evaluate the achievement of surgical goals and predict the prognosis of these tumors. Authors of the present study investigated the factors related to necessity of retreatment and tried to identify any surgical nuances achievable with the aid of modern neurosurgical techniques for meningiomas treated using Simpson Grade IV resection. METHODS: This retrospective analysis included patients with WHO Grade I meningiomas treated using Simpson Grade IV resection as the initial therapy at the University of Tokyo Hospital between January 1995 and April 2010. Retreatment was defined as reresection or stereotactic radiosurgery due to postoperative tumor growth. RESULTS: A total of 38 patients were included in this study. Regrowth of residual tumor was observed in 22 patients with a mean follow-up period of 6.1 years. Retreatment was performed for 20 of these 22 tumors with regrowth. Risk factors related to significantly shorter retreatment-free survival were age younger than 50 years (p = 0.006), postresection tumor volume of 4 cm(3) or more (p = 0.016), no dural detachment (p = 0.001), and skull base location (p = 0.016). Multivariate analysis revealed that no dural detachment (hazard ratio [HR] 6.42, 95% CI 1.41-45.0; p = 0.02) and skull base location (HR 11.6, 95% CI 2.18-218; p = 0.002) were independent risk factors for the necessity of early retreatment, whereas postresection tumor volume of 4 cm(3) or more was not a statistically significant risk factor. CONCLUSIONS: Compared with Simpson Grade I, II, and III resections, Simpson Grade IV resection includes highly heterogeneous tumors in terms of resection rate and location of the residual mass. Despite the difficulty in analyzing such diverse data, these results draw attention to the favorable effect of dural detachment (instead of maximizing the resection rate) on long-term tumor control. Surgical strategy with an emphasis on detaching the tumor from the affected dura might be another important option in resection of high-risk meningiomas not amenable to gross-total resection.
Simpson grading is used to describe resection of which brain tumor?
56c1f010ef6e394741000041_005
{ "answer_start": [ 58 ], "text": [ "meningioma" ] }
Evaluating the quality of Marfan genotype-phenotype correlations in existing FBN1 databases. BACKGROUND: Genetic FBN1 testing is pivotal for confirming the clinical diagnosis of Marfan syndrome. In an effort to evaluate variant causality, FBN1 databases are often used. We evaluated the current databases regarding FBN1 variants and validated associated phenotype records with a new Marfan syndrome geno-phenotyping tool called the Marfan score. METHODS AND RESULTS: We evaluated four databases (UMD-FBN1, ClinVar, the Human Gene Mutation Database (HGMD), and Uniprot) containing 2,250 FBN1 variants supported by 4,904 records presented in 307 references. The Marfan score calculated for phenotype data from the records quantified variant associations with Marfan syndrome phenotype. We calculated a Marfan score for 1,283 variants, of which we confirmed the database diagnosis of Marfan syndrome in 77.1%. This represented only 35.8% of the total registered variants; 18.5-33.3% (UMD-FBN1 versus HGMD) of variants associated with Marfan syndrome in the databases could not be confirmed by the recorded phenotype. CONCLUSION: FBN1 databases can be imprecise and incomplete. Data should be used with caution when evaluating FBN1 variants. At present, the UMD-FBN1 database seems to be the biggest and best curated; therefore, it is the most comprehensive database. However, the need for better genotype-phenotype curated databases is evident, and we hereby present such a database.Genet Med advance online publication 01 December 2016.
Which gene mutations cause the Marfan syndrome?
58d8e6818acda3452900000a_007
{ "answer_start": [ 113 ], "text": [ "FBN1" ] }
Anti-ischemic effect of a novel cardioprotective agent, JTV519, is mediated through specific activation of delta-isoform of protein kinase C in rat ventricular myocardium. BACKGROUND: A new 1,4-benzothiazepine derivative, JTV519, has a strong protective effect against Ca(2+) overload-induced myocardial injury. We investigated the effect of JTV519 on ischemia/reperfusion injury in isolated rat hearts. METHODS AND RESULTS: At 30 minutes of reperfusion after 30-minute global ischemia, the percent recovery of left ventricular developed pressure was improved, and the creatine phosphokinase and lactate dehydrogenase leakage was reduced in a concentration-dependent manner when JTV519 was administered in the coronary perfusate both at 5 minutes before the induction of ischemia and at the time of reperfusion. The myocardial protective effect of JTV519 was completely blocked by pretreatment of the heart with GF109203X, a specific protein kinase C (PKC) inhibitor. In contrast, the effect of JTV519 was not affected by alpha(1)-, A(1)-, and B(2)-receptor blockers that couple with PKC in the cardiomyocyte. Both immunofluorescence images and immunoblots of JTV519-treated left ventricular myocardium and isolated ventricular myocytes demonstrated that this agent induced concentration-dependent translocation of the delta-isoform but not the other isoforms of PKC to the plasma membrane. CONCLUSIONS: The mechanism of cardioprotection by JTV519 against ischemia/reperfusion injury involves isozyme-specific PKC activation through a receptor-independent mechanism. This agent may provide a novel pharmacological approach for the treatment of patients with acute coronary diseases via a subcellular mechanism mimicking ischemic preconditioning.
The drug JTV519 is derivative of which group of chemical compounds?
54f9b74306d9727f76000004_038
{ "answer_start": [ 190 ], "text": [ "1,4-benzothiazepine" ] }
Small heat shock protein 20 interacts with protein phosphatase-1 and enhances sarcoplasmic reticulum calcium cycling. BACKGROUND: Heat shock proteins (Hsp) are known to enhance cell survival under various stress conditions. In the heart, the small Hsp20 has emerged as a key mediator of protection against apoptosis, remodeling, and ischemia/reperfusion injury. Moreover, Hsp20 has been implicated in modulation of cardiac contractility ex vivo. The objective of this study was to determine the in vivo role of Hsp20 in the heart and the mechanisms underlying its regulatory effects in calcium (Ca) cycling. METHODS AND RESULTS: Hsp20 overexpression in intact animals resulted in significant enhancement of cardiac function, coupled with augmented Ca cycling and sarcoplasmic reticulum Ca load in isolated cardiomyocytes. This was associated with specific increases in phosphorylation of phospholamban (PLN) at both Ser16 and Thr17, relieving its inhibition of the apparent Ca affinity of SERCA2a. Accordingly, the inotropic effects of Hsp20 were abrogated in cardiomyocytes expressing nonphosphorylatable PLN (S16A/T17A). Interestingly, the activity of type 1 protein phosphatase (PP1), a known regulator of PLN signaling, was significantly reduced by Hsp20 overexpression, suggesting that the Hsp20 stimulatory effects are partially mediated through the PP1-PLN axis. This hypothesis was supported by cell fractionation, coimmunoprecipitation, and coimmunolocalization studies, which revealed an association between Hsp20, PP1, and PLN. Furthermore, recombinant protein studies confirmed a physical interaction between AA 73 to 160 in Hsp20 and AA 163 to 330 in PP1. CONCLUSIONS: Hsp20 is a novel regulator of sarcoplasmic reticulum Ca cycling by targeting the PP1-PLN axis. These findings, coupled with the well-recognized cardioprotective role of Hsp20, suggest a dual benefit of targeting Hsp20 in heart disease.
Which protein phosphatase has been found to interact with the heat shock protein, HSP20?
5506ce078e1671127b00000b_003
{ "answer_start": [ 1525 ], "text": [ "PP1" ] }
Oxantel disrupts polymicrobial biofilm development of periodontal pathogens. Bacterial pathogens commonly associated with chronic periodontitis are the spirochete Treponema denticola and the Gram-negative, proteolytic species Porphyromonas gingivalis and Tannerella forsythia. These species rely on complex anaerobic respiration of amino acids, and the anthelmintic drug oxantel has been shown to inhibit fumarate reductase (Frd) activity in some pathogenic bacteria and inhibit P. gingivalis homotypic biofilm formation. Here, we demonstrate that oxantel inhibited P. gingivalis Frd activity with a 50% inhibitory concentration (IC50) of 2.2 μM and planktonic growth of T. forsythia with a MIC of 295 μM, but it had no effect on the growth of T. denticola. Oxantel treatment caused the downregulation of six P. gingivalis gene products and the upregulation of 22 gene products. All of these genes are part of a regulon controlled by heme availability. There was no large-scale change in the expression of genes encoding metabolic enzymes, indicating that P. gingivalis may be unable to overcome Frd inhibition. Oxantel disrupted the development of polymicrobial biofilms composed of P. gingivalis, T. forsythia, and T. denticola in a concentration-dependent manner. In these biofilms, all three species were inhibited to a similar degree, demonstrating the synergistic nature of biofilm formation by these species and the dependence of T. denticola on the other two species. In a murine alveolar bone loss model of periodontitis oxantel addition to the drinking water of P. gingivalis-infected mice reduced bone loss to the same level as the uninfected control.
Oxantel is used for periodontitis treatment. How does it work?
530c7f52970c65fa6b000010_001
{ "answer_start": [ 0 ], "text": [ "Oxantel disrupts polymicrobial biofilm" ] }
Differential response of p53 target genes to p73 overexpression in SH-SY5Y neuroblastoma cell line. p73, the first p53 gene homologue, encodes an array of p73 proteins including p73 alpha full-length (TAp73 alpha) and amino-truncated isoforms (Delta Np73 alpha), two proteins with opposite biological functions. TAp73 alpha can induce tumor suppressive properties, while Delta Np73 alpha antagonizes p53 as well as TAp73 in a dominant-negative manner. In human malignant neuroblasts, p53 protein is wild-type but known to be excluded from the nucleus, therefore disabling its function as a tumor suppressor. The present study investigates whether there is a functional link between p73 isoforms and p53 in neuroblastoma. Experiments were performed on two neuroblastoma cell lines differing in their p53 status, e.g. wild-type p53 SH-5Y5Y cells and mutated p53 IGR-N-91 cells. Data indicate that (i) both TA- and Delta N-p73 alpha enhance p53 protein level in SH-SY5Y cells, whereas level remains unchanged in IGR-N-91 cells; (ii) only in SH-SY5Y cells does forced TAp73 alpha overexpression markedly induce nuclear accumulation of p53 protein; (iii) p21 protein expression is increased in both cell lines infected with TAp73, suggesting that, in IGR-N-91 cells, p21 is induced by p73 through a p53-independent pathway; (iv) in the SHSY5Y cell line, Btg2 expression is strongly enhanced in cells overexpressing TA, and to a lesser extent in cells overexpressing Delta N. Taken together our results suggest that TAp73 may restore p53 function in NB with wild-type nonfunctional p53, but not in NB with mutated p53.
How many TAp73 isoforms have been identified in humans?
5173bdb38ed59a060a000020_081
{ "answer_start": [ 252 ], "text": [ "7" ] }
Daratumumab and its potential in the treatment of multiple myeloma: overview of the preclinical and clinical development. Despite the recent major advancement in therapy for multiple myeloma, it remains an incurable disease. There remains an unmet need for novel therapies that target different mechanisms of action. Immunotherapy with monoclonal antibodies is a promising area of development and will expand our therapeutic armamentarium in the fight against myeloma. Daratumumab is a novel, high-affinity, therapeutic human monoclonal antibody against unique CD38 epitope with broad-spectrum killing activity. It has a favorable safety profile as monotherapy in patients with relapsed/refractory myeloma and also demonstrates significant single-agent activity. Abundant preclinical data supports its use in combination therapy and clinical studies on various exciting combinations are underway. This review focuses on the CD38 antigen and its targeting with daratumumab and provides an update on the results of recent clinical studies involving daratumumab.
Which molecule is targeted by Daratumumab?
56c04412ef6e39474100001b_011
{ "answer_start": [ 561 ], "text": [ "CD38" ] }
Update on denosumab in the management of postmenopausal osteoporosis: patient preference and adherence. Patient adherence to many osteoporosis treatments, primarily bisphosphonates, is generally poor, thus leading to a significant reduction in antifracture efficacy. Patient perceptions about the necessity of the prescribed medication to treat osteoporosis and the concerns about the potential adverse effects are important and potentially modifiable determinants of adherence, in addition to other factors, such as difficult dosing regimens and high dosing frequency. Denosumab (Dmab) is a fully human monoclonal antibody against the receptor activator of nuclear factor-κB ligand (RANKL), which, through the prevention of the RANKL/RANK interaction, inhibits osteoclast-mediated bone resorption and significantly reduces the risk of vertebral, nonvertebral, and hip fractures. It is administered subcutaneously every 6 months for the treatment of postmenopausal osteoporosis. Preference and adherence to Dmab treatment were assessed in various clinical trials. Although with some limitations, available data suggest that Dmab is preferred to bisphosphonates, produces greater satisfaction than bisphosphonates, and would be preferentially chosen for long-term treatment. Moreover, patient perceptions about the necessity of Dmab treatment clearly outweigh the concerns about the injections, and positive beliefs about treatment positively influence medication-taking behavior. According to these data, Dmab may represent a reasonable alternative to bisphosphonates, particularly for osteoporotic women in whom a suboptimal or even poor adherence to oral treatments is expected.
Which is the target of the drug Denosumab?
56e6ec49edfc094c1f000005_003
{ "answer_start": [ 684 ], "text": [ "RANKL" ] }
Safety, tolerability, pharmacokinetics and pharmacodynamics of single doses of empagliflozin, a sodium glucose cotransporter 2 (SGLT2) inhibitor, in healthy Japanese subjects. This randomized, placebo-controlled within dose groups, double-blind, single rising dose study investigated the safety, tolerability, pharmacokinetics and pharmacodynamics of 1 mg to 100 mg doses of empagliflozin in 48 healthy Japanese male subjects. Empagliflozin was rapidly absorbed, reaching peak levels in 1.25 to 2.50 h; thereafter, plasma concentrations declined in a biphasic fashion, with mean terminal elimination half-life ranging from 7.76 to 11.7 h. Increase in empagliflozin exposure was proportional to dose. Oral clearance was dose independent and ranged from 140 to 172 mL/min. In the 24 h following 100 mg empagliflozin administration, the mean (%CV) amount of glucose excreted in urine was 74.3 (17.1) g. The amount and the maximum rate of glucose excreted via urine increased with dose of empagliflozin. Nine adverse events, all of mild intensity, were reported by 8 subjects (7 with empagliflozin and 1 with the placebo). No hypoglycemia was reported. In conclusion, 1 mg to 100 mg doses of empagliflozin had a good safety and tolerability profile in healthy Japanese male subjects. Exposure to empagliflozin was dose proportional. The amount and rate of urinary glucose excretion were higher with empagliflozin than with the placebo, and increased with empagliflozin dose.
Which protein does empagliflozin inhibit?
571e12097de986d80d000017_004
{ "answer_start": [ 128 ], "text": [ "SGLT2" ] }
Practical perspectives on the use of tipranavir in combination with other medications: lessons learned from pharmacokinetic studies. Drug-drug interactions are a major practical concern for physicians treating human immunodeficiency virus (HIV) because of the many medications that HIV-positive patients must take. Pharmacokinetic drug interactions can occur at different levels (absorption, distribution, metabolism, excretion) and are difficult to predict. Of all the processes that give rise to drug interactions, metabolism by cytochrome P450 (CYP3A) is the most frequent. Moreover, medications prescribed to HIV-positive patients may also be CYP3A inhibitors and inducers: Tipranavir, in the absence of ritonavir, is a CYP3A inducer, and ritonavir is a CYP3A inhibitor. Fortunately, the drug interactions between tipranavir coadministered with ritonavir and other antiretroviral medications or with other medications commonly used in HIV therapy are well characterized. This review summarizes the pharmacokinetic interactions between tipranavir/ritonavir and 11 other antiretroviral medications and between tipranavir/ritonavir and drugs used to treat opportunistic infections such as fungal infections, antiretroviral-treatment-related conditions such as hyperlipidemia, and side effects such as diarrhea.
Cytochrome p450 CYP3A is induced by rifampicin and compounds used to treat what virus?
5ab2cc66fcf4565872000015_003
{ "answer_start": [ 613 ], "text": [ "HIV" ] }
The p53-binding protein 1-Tudor-interacting repair regulator complex participates in the DNA damage response. The 53BP1-dependent end-joining pathway plays a critical role in double strand break repair and is uniquely responsible for cellular sensitivity to poly(ADP-ribose) polymerase inhibitors (PARPi) in BRCA1-deficient cancers. We and others have investigated the downstream effectors of 53BP1, including replication timing regulatory factor 1 (RIF1) and Pax transactivation domain-interacting protein (PTIP), in the past few years to elucidate how loss of the 53BP1-dependent repair pathway results in PARPi resistance in BRCA1 patients. However, questions regarding the upstream regulation of the 53BP1 pathway remain unanswered. In this study, we identified the Tudor-interacting repair regulator (TIRR) that specifically associates with the ionizing radiation-induced foci formation region of 53BP1. 53BP1 and TIRR form a stable complex, which is required for their expression. Moreover, the 53BP1-TIRR complex dissociates after DNA damage, and this dissociation may be ataxia telangiectasia mutated-dependent. Similar to 53BP1, loss of TIRR restores PARPi resistance in BRCA1-deficient cells. Collectively, our data identified a novel 53BP1-TIRR complex in DNA damage response. TIRR may play both positive and negative roles in 53BP1 regulation. On the one hand, it stabilizes 53BP1 and thus positively regulates 53BP1. On the other hand, its association with 53BP1 prevents 53BP1 localization to sites of DNA damage, and thus TIRR is also an inhibitor of 53BP1.
Which protein is regulated by Tudor interacting repair regulator (TIRR)?
5a774fdcfaa1ab7d2e000008_007
{ "answer_start": [ 1338 ], "text": [ "53BP1" ] }
Subpallial Enhancer Transgenic Lines: a Data and Tool Resource to Study Transcriptional Regulation of GABAergic Cell Fate. Elucidating the transcriptional circuitry controlling forebrain development requires an understanding of enhancer activity and regulation. We generated stable transgenic mouse lines that express CreER and GFP from ten different enhancer elements with activity in distinct domains within the embryonic basal ganglia. We used these unique tools to generate a comprehensive regional fate map of the mouse subpallium, including sources for specific subtypes of amygdala neurons. We then focused on deciphering transcriptional mechanisms that control enhancer activity. Using machine-learning computations, in vivo chromosomal occupancy of 13 transcription factors that regulate subpallial patterning and differentiation and analysis of enhancer activity in Dlx1/2 and Lhx6 mutants, we elucidated novel molecular mechanisms that regulate region-specific enhancer activity in the developing brain. Thus, these subpallial enhancer transgenic lines are data and tool resources to study transcriptional regulation of GABAergic cell fate.
Which resource has been developed in order to study the transcriptional regulation of GABAergic cell fate?
5a6d196db750ff4455000032_003
{ "answer_start": [ 1027 ], "text": [ "subpallial enhancer transgenic lines" ] }
Stress Responses in Alfalfa (Medicago sativa L.) : V. Constitutive and Elicitor-Induced Accumulation of Isoflavonoid Conjugates in Cell Suspension Cultures. The isoflavonoid conjugates medicarpin-3-O-glucoside-6''-O-malonate (MGM), afrormosin-7-O-glucoside (AG), and afrormosin-7-O-glucoside-6''-O-malonate (AGM) were isolated and characterized from cell suspension cultures of alfalfa (Medicago sativa L.), where they were the major constitutive secondary metabolites. They were also found in alfalfa roots but not in other parts of the plant. The phytoalexin medicarpin accumulated rapidly in suspension cultured cells treated with elicitor from Colletotrichum lindemuthianum, and this was subsequently accompanied by an increase in the levels of MGM. In contrast, net accumulation of afrormosin conjugates was not affected by elicitor treatment. Labeling studies with [(14)C]phenylalanine indicated that afrormosin conjugates were the major de novo synthesized isoflavonoid products in unelicited cells. During elicitation, [(14)C]phenylalanine was incorporated predominantly into medicarpin, although a significant proportion of the newly synthesized medicarpin was also conjugated. Treatment of (14)C-labeled, elicited cells with l-alpha-aminooxy-beta-phenylpropionic acid, a potent inhibitor of PAL activity in vivo, resulted in the initial appearance of labeled medicarpin of very low specific activity, suggesting that the phytoalexin could be released from a preformed conjugate under these conditions. Our data draw attention to the involvement of isoflavone hydroxylases during the constitutive and elicitor-induced accumulation of isoflavonoids and their conjugates in alfalfa cell cultures.
Which is the major phytoalexin in alfalfa (Medicago sativa L.)?
5543829fed966d112c000009_007
{ "answer_start": [ 185 ], "text": [ "medicarpin" ] }
Synphilin isoforms and the search for a cellular model of lewy body formation in Parkinson's disease. A common finding in many neurodegenerative diseases is the presence of inclusion bodies made of aggregated proteins in neurons of affected brain regions. In Parkinson's disease, the inclusion bodies are referred to as Lewy bodies and their main component is alpha-synuclein. Although many studies have suggested that inclusion bodies may be cell protective, it is still not clear whether Lewy bodies promote or inhibit dopaminergic cell death in Parkinson's disease. Synphilin-1 interacts with alpha-synuclein and is present in Lewy bodies. Accumulation of ubiquitylated synphilin-1 leads to massive formation of inclusion bodies, which resemble Lewy bodies by their ability to recruit alpha-synuclein. We have recently isolated an isoform of synphilin-1, synphilin-1A, that spontaneously aggregates in cells, and is present in detergent-insoluble fractions of brain protein samples from alpha-synucleinopathy patients. Synphilin-1A displays marked neuronal toxicity and, upon proteasome inhibition, accumulates into ubiquitylated inclusions with concomitant reduction of its intrinsic toxicity. The fact that alpha-synuclein interacts with synphilin-1A, and is recruited to synphilin-1A inclusion bodies in neurons together with synphilin-1, further indicates that synphilin-1A cell model is relevant for research on Parkinson's disease. Synphilin-1A cell model may help provide important insights regarding the role of inclusion bodies in Parkinson's disease and other neurodegenerative disorders.
What is the main component of the Lewy bodies?
550c3d45a103b78016000008_015
{ "answer_start": [ 360 ], "text": [ "alpha-synuclein" ] }
Altered cell surface expression of human MC1R variant receptor alleles associated with red hair and skin cancer risk. The human melanocortin-1 receptor gene (MC1R) encodes a G-protein coupled receptor that is primarily expressed on melanocytes, where it plays a key role in pigmentation regulation. Variant alleles are associated with red hair colour and fair skin, known as the RHC phenotype, as well as skin cancer risk. The R151C, R160W and D294H alleles, designated 'R', are strongly associated with the RHC phenotype and have been proposed to result in loss of function receptors due to impaired G-protein coupling. We recently provided evidence that the R151C and R160W variants can efficiently couple to G-proteins in response to alpha-melanocyte stimulating hormone. The possibility that altered cellular localization of the R151C and R160W variant receptors could underlie their association with RHC was therefore considered. Using immunofluorescence and ligand binding studies, we found that melanocytic cells exogenously or endogenously expressing MC1R show strong surface localization of the wild-type and D294H alleles but markedly reduced cell surface expression of the R151C and R160W receptors. In additional exogenous expression studies, the R variant D84E and the rare I155T variant, also demonstrated a significant reduction in plasma membrane receptor numbers. The V60L, V92M and R163Q weakly associated RHC alleles, designated 'r', were expressed with normal or intermediate cell surface receptor levels. These results indicate that reduced receptor coupling activity may not be the only contributing factor to the genetic association between the MC1R variants and the RHC phenotype, with MC1R polymorphisms now linked to a change in receptor localization.
Which gene is responsible for red hair?
5ace19420340b9f05800000a_018
{ "answer_start": [ 41 ], "text": [ "MC1R" ] }
Orteronel plus prednisone in patients with chemotherapy-naive metastatic castration-resistant prostate cancer (ELM-PC 4): a double-blind, multicentre, phase 3, randomised, placebo-controlled trial. BACKGROUND: Orteronel is an investigational, partially selective inhibitor of CYP 17,20-lyase in the androgen signalling pathway, a validated therapeutic target for metastatic castration-resistant prostate cancer. We assessed orteronel in chemotherapy-naive patients with metastatic castration-resistant prostate cancer. METHODS: In this phase 3, double-blind, placebo-controlled trial, we recruited patients with progressive metastatic castration-resistant prostate cancer and no previous chemotherapy from 324 study centres (ie, hospitals or large urologic or group outpatient offices) in 43 countries. Eligible patients were randomly assigned in a 1:1 ratio to receive either 400 mg orteronel plus 5 mg prednisone twice daily or placebo plus 5 mg prednisone twice daily. Randomisation was done centrally with an interactive voice response system and patients were stratified by region (Europe, North America, and not Europe or North America) and the presence or absence of radiographic disease progression at baseline. The two primary endpoints were radiographic progression-free survival and overall survival, determined in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT01193244. FINDINGS: From Oct 31, 2010, to June 29, 2012, 2353 patients were assessed for eligibility. Of those, 1560 were randomly assigned to receive either orteronel plus prednisone (n=781) or placebo plus prednisone (n=779). The clinical cutoff date for the final analysis was Jan 15, 2014 (with 611 deaths). Median follow-up for radiographic progression-free survival was 8·4 months (IQR 3·7-16·6). Median radiographic progression-free survival was 13·8 months (95% CI 13·1-14·9) with orteronel plus prednisone and 8·7 months (8·3-10·9) with placebo plus prednisone (hazard ratio [HR] 0·71, 95% CI 0·63-0·80; p<0·0001). After a median follow-up of 20·7 months (IQR 14·2-25·4), median overall survival was 31·4 months (95% CI 28·6-not estimable) with orteronel plus prednisone and 29·5 months (27·0-not estimable) with placebo plus prednisone (HR 0·92, 95% CI 0·79-1·08; p=0·31). The most common grade 3 or worse adverse events were increased lipase (137 [17%] of 784 patients in the orteronel plus prednisone group vs 14 [2%] of 770 patients in the placebo plus prednisone group), increased amylase (77 [10%] vs nine [1%]), fatigue (50 [6%] vs 14 [2%]), and pulmonary embolism (40 [5%] vs 27 [4%]). Serious adverse events were reported in 358 [46%] patients receiving orteronel plus prednisone and in 292 [38%] patients receiving placebo plus prednisone. INTERPRETATION: In chemotherapy-naive patients with metastatic castration-resistant prostate cancer, radiographic progression-free survival was prolonged with orteronel plus prednisone versus placebo plus prednisone. However, no improvement was noted in the other primary endpoint, overall survival. Orteronel plus prednisone was associated with increased toxic effects compared with placebo plus prednisone. On the basis of these and other data, orteronel is not undergoing further development in metastatic castration-resistant prostate cancer. FUNDING: Millennium Pharmaceuticals, Inc, a wholly owned subsidiary of Takeda Pharmaceutical Company Limited.
Orteronel was developed for treatment of which cancer?
56c1f01def6e394741000045_012
{ "answer_start": [ 481 ], "text": [ "castration-resistant prostate cancer" ] }
Endothelial deletion of Sag/Rbx2/Roc2 E3 ubiquitin ligase causes embryonic lethality and blocks tumor angiogenesis. SAG (Sensitive to Apoptosis Gene), also known as RBX2 or ROC2, is a RING protein required for the activity of Cullin-RING ligase (CRL). Our recent study showed that Sag total knockout caused embryonic lethality at E11.5-12.5 days with associated defects in vasculogenesis. Whether Sag is required for de novo vasculogenesis in embryos and angiogenesis in tumors is totally unknown. Here, we report that Sag endothelial deletion also causes embryonic lethality at E15.5 with poor vasculogenesis. Sag deletion in primary endothelial cells (ECs) or knockdown in MS-1 ECs inhibits migration, proliferation and tube formation, with p27 accumulation being responsible for the suppression of migration and proliferation. Furthermore, Sag deletion significantly inhibits angiogenesis in an in vivo Matrigel plug assay, and tumor angiogenesis and tumorigenesis in a B16F10 melanoma model. Finally, MLN4924, an investigational small molecule inhibitor of NEDD8-activating enzyme (NAE) that inhibits CRL, suppresses in vitro migration, proliferation and tube formation, as well as in vivo angiogenesis and tumorigenesis. Taken together, our study, using both genetic and pharmaceutical approaches, demonstrates that Sag is essential for embryonic vasculogenesis and tumor angiogenesis, and provides the proof-of-concept evidence that targeting Sag E3 ubiquitin ligase may have clinical value for anti-angiogenesis therapy of human cancer.
Which enzyme does MLN4924 inhibit?
56ed03862ac5ed1459000004_001
{ "answer_start": [ 1061 ], "text": [ "NEDD8-activating enzyme" ] }
Mutations in the ribosomal protein genes in Japanese patients with Diamond-Blackfan anemia. BACKGROUND: Diamond-Blackfan anemia is a rare, clinically heterogeneous, congenital red cell aplasia: 40% of patients have congenital abnormalities. Recent studies have shown that in western countries, the disease is associated with heterozygous mutations in the ribosomal protein (RP) genes in about 50% of patients. There have been no studies to determine the incidence of these mutations in Asian patients with Diamond-Blackfan anemia. DESIGN AND METHODS: We screened 49 Japanese patients with Diamond-Blackfan anemia (45 probands) for mutations in the six known genes associated with Diamond-Blackfan anemia: RPS19, RPS24, RPS17, RPL5, RPL11, and RPL35A. RPS14 was also examined due to its implied involvement in 5q- syndrome. RESULTS: Mutations in RPS19, RPL5, RPL11 and RPS17 were identified in five, four, two and one of the probands, respectively. In total, 12 (27%) of the Japanese Diamond-Blackfan anemia patients had mutations in ribosomal protein genes. No mutations were detected in RPS14, RPS24 or RPL35A. All patients with RPS19 and RPL5 mutations had physical abnormalities. Remarkably, cleft palate was seen in two patients with RPL5 mutations, and thumb anomalies were seen in six patients with an RPS19 or RPL5 mutation. In contrast, a small-for-date phenotype was seen in five patients without an RPL5 mutation. CONCLUSIONS: We observed a slightly lower frequency of mutations in the ribosomal protein genes in patients with Diamond-Blackfan anemia compared to the frequency reported in western countries. Genotype-phenotype data suggest an association between anomalies and RPS19 mutations, and a negative association between small-for-date phenotype and RPL5 mutations.
Which class of genes are mutated in Diamond Blackfan Anemia patients?
58e74bff3e8b6dc87c000004_008
{ "answer_start": [ 17 ], "text": [ "ribosomal protein genes" ] }
McLeod phenotype without the McLeod syndrome. BACKGROUND: McLeod neuroacanthocytosis syndrome is a late-onset X-linked multisystem disorder affecting the peripheral and central nervous systems, red blood cells (RBCs), and internal organs. A variety of mutations have been found in the responsible gene (XK) including single nonsense and missense mutations, nucleotide mutations at or near the splice junctions of introns of XK, and different deletion mutations. To date no clear phenotype-genotype correlation is apparent. The clinical details of one case of McLeod phenotype without apparent neuromuscular abnormalities have been reported. Here the clinical details of two additional cases are presented, of which the genetic details have previously been published. STUDY DESIGN AND METHODS: Two asymptomatic or minimally symptomatic cases at ages expected to manifest the McLeod syndrome (MLS) were evaluated. The first case had been authenticated as a genuine McLeod both by serology and by genotyping (R222G missense mutation) and the second case had a mutation in XK (IVS2+5G>A) and by serology exhibited very weak Kx antigen and no detectable Kell antigens, except extremely low k antigen by adsorption-elution technique. The patients were examined for hematologic, neurologic, and other clinical abnormalities. RESULTS: Despite documented McLeod phenotype on RBCs, and identified mutations of XK, neurologic and other clinical findings were minimal at ages expected to manifest MLS. CONCLUSIONS: The different XK mutations may have different effects upon the XK gene product and thus may account for the variable phenotype.
Mutation of which gene is associated with McLeod syndrome?
531464a6e3eabad021000014_018
{ "answer_start": [ 1069 ], "text": [ "XK" ] }
H2A histone-fold and DNA elements in nucleosome activate SWR1-mediated H2A.Z replacement in budding yeast. The histone variant H2A.Z is a universal mark of gene promoters, enhancers, and regulatory elements in eukaryotic chromatin. The chromatin remodeler SWR1 mediates site-specific incorporation of H2A.Z by a multi-step histone replacement reaction, evicting histone H2A-H2B from the canonical nucleosome and depositing the H2A.Z-H2B dimer. Binding of both substrates, the canonical nucleosome and the H2A.Z-H2B dimer, is essential for activation of SWR1. We found that SWR1 primarily recognizes key residues within the α2 helix in the histone-fold of nucleosomal histone H2A, a region not previously known to influence remodeler activity. Moreover, SWR1 interacts preferentially with nucleosomal DNA at superhelix location 2 on the nucleosome face distal to its linker-binding site. Our findings provide new molecular insights on recognition of the canonical nucleosome by a chromatin remodeler and have implications for ATP-driven mechanisms of histone eviction and deposition.
Which protein mediates the replacement of H2A by H2A.Z in the yeast Saccharomyces cerevisiae?
58a6db8660087bc10a00002c_027
{ "answer_start": [ 57 ], "text": [ "SWR1" ] }
Shprintzen-Goldberg syndrome: fourteen new patients and a clinical analysis. The Shprintzen-Goldberg syndrome (SGS) is a disorder of unknown cause comprising craniosynostosis, a marfanoid habitus and skeletal, neurological, cardiovascular, and connective-tissue anomalies. There are no pathognomonic signs of SGS and diagnosis depends on recognition of a characteristic combination of anomalies. Here, we describe 14 persons with SGS and compare their clinical findings with those of 23 previously reported individuals, including two families with more than one affected individual. Our analysis suggests that there is a characteristic facial appearance, with more than two thirds of all individuals having hypertelorism, down-slanting palpebral fissures, a high-arched palate, micrognathia, and apparently low-set and posteriorly rotated ears. Other commonly reported manifestations include hypotonia in at least the neonatal period, developmental delay, and inguinal or umbilical hernia. The degree of reported intellectual impairment ranges from mild to severe. The most common skeletal manifestations in SGS were arachnodactyly, pectus deformity, camptodactyly, scoliosis, and joint hypermobility. None of the skeletal signs alone is specific for SGS. Our study includes 14 mainly German individuals with SGS evaluated over a period of 10 years. Given that only 23 other persons with SGS have been reported to date worldwide, we suggest that SGS may be more common than previously assumed.
Which disease is included as an additional feature in the Goldberg-Shprintzen syndrome?
5519110f622b19434500000c_006
{ "answer_start": [ 158 ], "text": [ "craniosynostosis" ] }
Minor lesion mutational spectrum of the entire NF1 gene does not explain its high mutability but points to a functional domain upstream of the GAP-related domain. More than 500 unrelated patients with neurofibromatosis type 1 (NF1) were screened for mutations in the NF1 gene. For each patient, the whole coding sequence and all splice sites were studied for aberrations, either by the protein truncation test (PTT), temperature-gradient gel electrophoresis (TGGE) of genomic PCR products, or, most often, by direct genomic sequencing (DGS) of all individual exons. A total of 301 sequence variants, including 278 bona fide pathogenic mutations, were identified. As many as 216 or 183 of the genuine mutations, comprising 179 or 161 different ones, can be considered novel when compared to the recent findings of Upadhyaya and Cooper, or to the NNFF mutation database. Mutation-detection efficiencies of the various screening methods were similar: 47.1% for PTT, 53.7% for TGGE, and 54.9% for DGS. Some 224 mutations (80.2%) yielded directly or indirectly premature termination codons. These mutations showed even distribution over the whole gene from exon 1 to exon 47. Of all sequence variants determined in our study, <20% represent C-->T or G-->A transitions within a CpG dinucleotide, and only six different mutations also occur in NF1 pseudogenes, with five being typical C-->T transitions in a CpG. Thus, neither frequent deamination of 5-methylcytosines nor interchromosomal gene conversion may account for the high mutation rate of the NF1 gene. As opposed to the truncating mutations, the 28 (10.1%) missense or single-amino-acid-deletion mutations identified clustered in two distinct regions, the GAP-related domain (GRD) and an upstream gene segment comprising exons 11-17. The latter forms a so-called cysteine/serine-rich domain with three cysteine pairs suggestive of ATP binding, as well as three potential cAMP-dependent protein kinase (PKA) recognition sites obviously phosphorylated by PKA. Coincidence of mutated amino acids and those conserved between human and Drosophila strongly suggest significant functional relevance of this region, with major roles played by exons 12a and 15 and part of exon 16.
Which is the gene mutated in type 1 neurofibromatosis?
5343fc1aaeec6fbd07000003_030
{ "answer_start": [ 227 ], "text": [ "NF1" ] }
New case of thyroid dysgenesis and clinical signs of hypothyroidism in Williams syndrome. The authors report a female presenting with congenital heart defects, liver hemangiomas, and facial dysmorphisms admitted to hospital at 3 months of age because of feeding difficulties and poor growth. She had hypotonia and large tongue, "coarse" face, and umbilical hernia in presence of complex congenital cardiovascular malformations. In spite of normal neonatal screening we performed serum levels of thyroid hormones. Thyrotropin level was very high (>50 microU/ml; normal value 0.2-4 microU/ml), while serum free T(3) (FT3) and free T(4) (FT4) levels were normal (FT3 3.6 pg/ml, normal value 2.8-5.6 pg/ml; FT4 11.6 pg/ml, normal value 6.6-14 pg/ml); antithyroid autoantibodies were absent. Thyroid scintigraphy with sodium 99m Tc pertechnetate showed a small ectopic thyroid located in sublingual position, so treatment with L-thyroxine 37.5 microg/24 hr was started with rapid improvement of the clinical picture. At 17 months of age the patient developed the complete characteristic phenotype of Williams syndrome (WS); the clinical diagnosis was proven by fluorescent in situ hybridization (FISH) analysis which showed hemizygous deletion of the elastin gene on chromosome 7. Recently a case of thyroid hemiagenesis in a child with WS has been reported; our patient underscores the association of hypothyroidism and WS. Moreover, our case shows that clinical manifestations of hypothyroidism may be present and the treatment may be necessary as it is in isolated congenital hypothyroidism.
Which hormone abnormalities are common in Williams syndrome ?
530cefaaad0bf1360c00000d_025
{ "answer_start": [ 1401 ], "text": [ "thyroid" ] }
[Molecular mechanism of tissue-specific actions of SERM]. Selective estrogen receptor modulator (SERM) is designated as synthetic ligands for estrogen receptors (ERs), exhibiting tissue-specific agonisitic/antagonisitic activities. Among SERM, raloxifen is a most clinically successful as an anti-oseteoporotic agent. Such tissue-specific actions of SERM are presumed to mediate through unusual structure alteration of liganded ERs coupled with co-regulator recruitments.
What is a SERM?
5a74e9ad0384be955100000a_021
{ "answer_start": [ 58 ], "text": [ "Selective estrogen receptor modulator" ] }
Thyroid hypoplasia as a cause of congenital hypothyroidism in Williams syndrome. In the Williams-Beuren syndrome (WBS), disorders of the thyroid function and morphology have been reported and programs of thyroid screening and surveillance are recommended. However, the frequency of biochemical thyroid assessment, particularly in the first year of life, is being debated. In this report we describe an infant with WBS and congenital hypothyroidism, due to an important thyroid hypoplasia. The patient, a 1-month-old female, negative at primary neonatal thyroid screening, was referred to our hospital for dyspnea. Thyroid function tests showed a raised TSH (42 mIU/l; normal range 0.5-4 mIU/l) with a low FT(4) concentration (10.21 pmol/l; normal range: 10.29-24.45 pmol/l). Ultrasound examination of the neck showed a significant thyroid hypoplasia, whereas (99m)Tc-pertechnetate thyroid scintigraphy evidenced a thyroid gland in normal position, with reduced shape and overall weak fixation. Therefore, treatment with L-thyroxinewas started. Thyroid hypoplasia is a frequent characteristic of WBS and abnormalities of thyroid function are common in patients with this feature. Therefore, the possibility of congenital hypothyroidism should always be taken into consideration too and, even if congenital hypothyroidism neonatal screening is negative, thyroid (morphology and function) evaluation should be regularly assessed when the diagnosis is made and, thereafter, every year in the first years of life.
Which hormone abnormalities are common in Williams syndrome ?
530cefaaad0bf1360c00000d_004
{ "answer_start": [ 437 ], "text": [ "thyroid" ] }
Second-generation tyrosine kinase inhibitors as therapy for chronic myeloid leukemia. Chronic myeloid leukemia (CML) was the first human malignancy to be associated with a single genetic abnormality, characterized by a reciprocal translocation involving chromosomes 9 and 22 (the Philadelphia chromosome). The fusion gene that results (BCR-ABL) produces a constitutively activated tyrosine kinase that exists in different isoforms depending on BCR break-points. Imatinib mesylate is a highly selective inhibitor of this kinase, producing normal blood-counts in 98% of patients in chronic phase CML and disappearance of the Philadelphia chromosome in 86%. However, 17% of patients in the chronic phase will either relapse or develop resistance resulting mainly from one or more point mutations affecting at least 30 amino acids within the Abl kinase protein. This review focuses on the relevant biology of CML, imatinib mesylate resistance mechanisms, and the current status of the next generation of Bcr-Abl inhibitors.
What tyrosine kinase, involved in a Philadelphia- chromosome positive chronic myelogenous leukemia, is the target of Imatinib (Gleevec)?
5324a8ac9b2d7acc7e000018_068
{ "answer_start": [ 336 ], "text": [ "BCR-ABL" ] }
Two novel tyrosinase (TYR) gene mutations with pathogenic impact on oculocutaneous albinism type 1 (OCA1). Oculocutaneous albinism (OCA) is a heterogeneous group of autosomal recessive disorders resulting from mutations of the tyrosinase (TYR) gene and presents with either complete or partial absence of pigment in the skin, hair and eyes due to a defect in an enzyme involved in the production of melanin. In this study, mutations in the TYR gene of 30 unrelated Iranian OCA1 patients and 100 healthy individuals were examined using PCR-sequencing. Additionally, in order to predict the possible effects of new mutations on the structure and function of tyrosinase, these mutations were analyzed by SIFT, PolyPhen and I-Mutant 2 software. Here, two new pathogenic p.C89S and p.H180R mutations were detected in two OCA1 patients. Moreover, the R402Q and S192Y variants, which are common non-pathogenic polymorphisms, were detected in 17.5% and 35% of the patients, respectively. The outcome of this study has extended the genotypic spectrum of OCA1 patients, which paves the way for more efficient carrier detection and genetic counseling.
Which mutated enzyme is responsible for oculocutaneous 1 (OCA1)-type albinism?
58cbb98c02b8c60953000034_112
{ "answer_start": [ 227 ], "text": [ "tyr" ] }
Chronic myelogenous leukemia with the e6a2 BCR-ABL and lacking imatinib response: presentation of two cases. The BCR-ABL fusion gene represents the hallmark of chronic myelogenous leukemia (CML) and is derived from a translocation between chromosome 9 and 22. The majority of CML patients have a breakpoint in the major BCR region of the BCR gene giving rise to e13a2 or e14a2 BCR-ABL transcripts. Occasionally, other BCR breakpoints occur. The current report describes two e6a2 CML patients with imatinib treatment failure and unusual disease progression. One patient was Philadelphia chromosome positive and one was Philadelphia chromosome negative with an atypical BCR-ABL rearrangement, ins (22;9).
What tyrosine kinase, involved in a Philadelphia- chromosome positive chronic myelogenous leukemia, is the target of Imatinib (Gleevec)?
5324a8ac9b2d7acc7e000018_055
{ "answer_start": [ 113 ], "text": [ "BCR-ABL" ] }
A clinical trial of escalating doses of flumazenil for reversal of suspected benzodiazepine overdose in the emergency department. STUDY OBJECTIVE: To determine if flumazenil, when used in doses higher than those currently recommended, could reverse the effects of a benzodiazepine (BDZ) overdose in patients who might not otherwise respond and whether the higher dose was associated with increased adverse effects. DESIGN: Multicenter, randomized, double-blind, placebo-controlled, balanced, with parallel groups. Open-label flumazenil administration was available if a patient failed to respond or became resedated. SETTING: Sixteen emergency departments in the United States. POPULATION: Patients presenting to the ED with clinically significant signs and symptoms of a known or suspected BDZ overdose. INTERVENTIONS: Patients were randomized to receive 10 mL/min of placebo or flumazenil (1 mg/10 mL) each minute for ten minutes. If there was no response, up to 3 mg of open-label flumazenil could be administered. MEASUREMENTS AND MAIN RESULTS: Of 170 patients enrolled, 87 received flumazenil and 83 received placebo. The demographic characteristics of both groups were comparable. Ten minutes after the beginning of study drug infusion, patients were evaluated using the Clinical Global Impression Scale (CGIS), Glasgow Coma Scale (GSC), and Neurobehavioral Assessment Scale (NAS). The mean +/- SD CGIS score at ten minutes for BDZ-positive patients was 1.41 +/- 0.72 for patients who received flumazenil and 3.41 +/- 0.91 for the placebo group (P < .01). There was no difference in the mean CGIS score between the flumazenil (3.25 +/- 1.15) and placebo (3.75 +/- 0.69) groups in BDZ-negative patients. The GCS and NAS were also significantly better in patients who were BDZ-positive and received flumazenil. The mean +/- SD dose of flumazenil administered during the double-blind phase was 71.3 +/- 34.2 mL (7.13 mg) compared with 95.06 +/- 16.03 mL of placebo. Of the 39 patients who had BDZ-positive drug screens and received flumazenil, 29 (74%) responded to 3 mg or less. Six additional patients responded to 4 or 5 mg, and one patient responded to 8 mg. The most common adverse effects in patients who received flumazenil were injection site pain (10.3%), agitation (8%), vomiting (3.4%), dizziness (3.4%), headache (3.4%), tachycardia (3.4%), and crying (3.4%). Three patients developed seizures. Two were associated with significant tricyclic antidepressant overdoses and one with propoxyphene ingestion. Two patients had positive drug screens for BDZ. CONCLUSION: Flumazenil rapidly and effectively reverses the clinical signs and symptoms of a BDZ overdose. Most patients will respond to 3 mg or less, but a small number may require a higher dose for reversal of clinical symptoms. Patients with concomitant tricyclic antidepressant overdose may be at risk for developing seizures.
Which drug should be used as an antidote in benzodiazepine overdose?
514a0a57d24251bc05000051_043
{ "answer_start": [ 1803 ], "text": [ "flumazenil" ] }
Sequestration of p53 in the cytoplasm by adenovirus type 12 E1B 55-kilodalton oncoprotein is required for inhibition of p53-mediated apoptosis. The adenovirus E1B 55-kDa protein is a potent inhibitor of p53-mediated transactivation and apoptosis. The proposed mechanisms include tethering the E1B repression domain to p53-responsive promoters via direct E1B-p53 interaction. Cytoplasmic sequestration of p53 by the 55-kDa protein would impose additional inhibition on p53-mediated effects. To investigate further the role of cytoplasmic sequestration of p53 in its inhibition by the E1B 55-kDa protein we systematically examined domains in both the Ad12 55-kDa protein and p53 that underpin their colocalization in the cytoplasmic body and show that the N-terminal transactivation domain (TAD) of p53 is essential for retaining p53 in the cytoplasmic body. Deletion of amino acids 11 to 27 or even point mutation L22Q/W23S abolished the localization of p53 to the cytoplasmic body, whereas other parts of TAD and the C-terminal domain of p53 are dispensable. This cytoplasmic body is distinct from aggresome associated with overexpression of some proteins, since it neither altered vimentin intermediate filaments nor associated with centrosome or ubiquitin. Formation of this structure is sensitive to mutation of the Ad12 55-kDa protein. Strikingly, mutation S476/477A near the C terminus of the Ad12 55-kDa protein eliminated the formation of the cytoplasmic body. The equivalent residues in the Ad5 55-kDa protein were shown to be critical for its ability to inhibit p53. Indeed, Ad12 55-kDa mutants that cannot form a cytoplasmic body can no longer inhibit p53-mediated effects. Conversely, the Ad12 55-kDa protein does not suppress p53 mutant L22Q/W23S-mediated apoptosis. Finally, we show that E1B can still sequester p53 that contains the mitochondrial import sequence, thereby potentially preventing the localization of p53 to mitochondria. Thus, cytoplasmic sequestration of p53 by the E1B 55-kDa protein plays an important role in restricting p53 activities.
What is the role of TAD protein domain?
58dcb47c8acda34529000020_004
{ "answer_start": [ 765 ], "text": [ "transactivation domain" ] }
Test-retest variability of serotonin 5-HT2A receptor binding measured with positron emission tomography and [18F]altanserin in the human brain. The role of serotonin in CNS function and in many neuropsychiatric diseases (e.g., schizophrenia, affective disorders, degenerative dementias) support the development of a reliable measure of serotonin receptor binding in vivo in human subjects. To this end, the regional distribution and intrasubject test-retest variability of the binding of [18F]altanserin were measured as important steps in the further development of [18F]altanserin as a radiotracer for positron emission tomography (PET) studies of the serotonin 5-HT2A receptor. Two high specific activity [18F]altanserin PET studies were performed in normal control subjects (n = 8) on two separate days (2-16 days apart). Regional specific binding was assessed by distribution volume (DV), estimates that were derived using a conventional four compartment (4C) model, and the Logan graphical analysis method. For both analysis methods, levels of [18F]altanserin binding were highest in cortical areas, lower in the striatum and thalamus, and lowest in the cerebellum. Similar average differences of 13% or less were observed for the 4C model DV determined in regions with high receptor concentrations with greater variability in regions with low concentrations (16-20%). For all regions, the absolute value of the test-retest differences in the Logan DV values averaged 12% or less. The test-retest differences in the DV ratios (regional DV values normalized to the cerebellar DV) determined by both data analysis methods averaged less than 10%. The regional [18F]altanserin DV values using both of these methods were significantly correlated with literature-based values of the regional concentrations of 5-HT2A receptors determined by postmortem autoradiographic studies (r2 = 0.95, P < 0.001 for the 4C model and r2 = 0.96, P < 0.001 for the Logan method). Brain uptake studies in rats demonstrated that two different radiolabeled metabolites of [18F]altanserin (present at levels of 3-25% of the total radioactivity in human plasma 10-120 min postinjection) were able to penetrate the blood-brain barrier. However, neither of these radiolabeled metabolites bound specifically to the 5-HT2A receptor and did not interfere with the interpretation of regional [18F]altanserin-specific binding parameters obtained using either a conventional 4C model or the Logan graphical analysis method. In summary, these results demonstrate that the test-retest variability of [18F]altanserin-specific binding is comparable to that of other PET radiotracers and that the regional specific binding of [18F]altanserin in human brain was correlated with the known regional distribution of 5-HT2A receptors. These findings support the usefulness of [18F]altanserin as a radioligand for PET studies of 5-HT2A receptors.
Which receptors can be evaluated with the [18F]altanserin?
55242d512c8b63434a000006_036
{ "answer_start": [ 664 ], "text": [ "5-HT2A" ] }
Prevention of JNK phosphorylation as a mechanism for rosiglitazone in neuroprotection after transient cerebral ischemia: activation of dual specificity phosphatase. Rosiglitazone, a synthetic peroxisome proliferator-activated receptor-γ (PPARγ) agonist, prevents cell death after cerebral ischemia in animal models, but the underlying mechanism has not been clarified. In this study, we examined how rosiglitazone protects neurons against ischemia. Mice treated with rosiglitazone were subjected to 60 minutes of focal ischemia followed by reperfusion. Rosiglitazone reduced infarct volume after ischemia and reperfusion. We show that this neuroprotective effect was reversed with a PPARγ antagonist. Western blot analysis showed a significant increase in expression of phosphorylated stress-activated protein kinases (c-Jun N-terminal kinase (JNK) and p38) in ischemic brain tissue. Rosiglitazone blocked this increase. Furthermore, we observed that rosiglitazone increased expression of the dual-specificity phosphatase 8 (DUSP8) protein and messenger RNA in ischemic brain tissue. Dual-specificity phosphatase 8 is a mitogen-activated protein kinase phosphatase that can dephosphorylate JNK and p38. Another key finding of the present study was that knockdown of DUSP8 in primary cultured cortical neurons that were subjected to oxygen-glucose deprivation diminished rosiglitazone's effect on downregulation of JNK phosphorylation. Thus, rosiglitazone's neuroprotective effect after ischemia is mediated by blocking JNK phosphorylation induced by ischemia via DUSP8 upregulation.
Which protein is affected by dusp8 activation?
5148691bd24251bc0500002d_002
{ "answer_start": [ 14 ], "text": [ "JNK" ] }
[STI571 (Glivec)--a new drug for the treatment of chronic myeloid leukemia]. Chronic myeloid leukaemia (CML) is characterised by the occurrence of the Philadelphia (Ph) chromosome (9/22 translocation) and the formation of a fusion protein--the BCR-ABL transcript with constitutive activation of the BCR-ABL tyrosine kinase and consequent changes in the intracellular signal transduction, which is responsible for the deregulated myeloid cell proliferation. STI571 (signal transduction inhibition number 571) is a potent and selective inhibitor of the BCR-ABL tyrosine kinase. In the chronic phase of the disease, normal peripheral blood values are achieved within the first month of treatment in the large majority of patients and in many patients also a cytogenic response within the following months. The results in the advanced phase are far less favourable, which is explained by the development of resistance owing to reactivation of the BCR-ABL signal transduction. Side effects are primarily nausea, vomiting, various rashes, oedema, most often in the periorbital region, and musculoskeletal symptoms, including muscle cramps. Perspectives for treatment with STI571 are described, as are combinations with alpha-interferon and other cytostatics with a synergistic profile.
What tyrosine kinase, involved in a Philadelphia- chromosome positive chronic myelogenous leukemia, is the target of Imatinib (Gleevec)?
5324a8ac9b2d7acc7e000018_091
{ "answer_start": [ 299 ], "text": [ "BCR-ABL" ] }
CAGEr: precise TSS data retrieval and high-resolution promoterome mining for integrative analyses. Cap analysis of gene expression (CAGE) is a high-throughput method for transcriptome analysis that provides a single base-pair resolution map of transcription start sites (TSS) and their relative usage. Despite their high resolution and functional significance, published CAGE data are still underused in promoter analysis due to the absence of tools that enable its efficient manipulation and integration with other genome data types. Here we present CAGEr, an R implementation of novel methods for the analysis of differential TSS usage and promoter dynamics, integrated with CAGE data processing and promoterome mining into a first comprehensive CAGE toolbox on a common analysis platform. Crucially, we provide collections of TSSs derived from most published CAGE datasets, as well as direct access to FANTOM5 resource of TSSs for numerous human and mouse cell/tissue types from within R, greatly increasing the accessibility of precise context-specific TSS data for integrative analyses. The CAGEr package is freely available from Bioconductor at http://www.bioconductor.org/packages/release/bioc/html/CAGEr.html.
Which tool is used for promoterome mining using CAGE data?
56afe6d40a360a5e45000017_002
{ "answer_start": [ 551 ], "text": [ "CAGEr" ] }
A novel mutation in the endosomal Na+/H+ exchanger NHE6 (SLC9A6) causes Christianson syndrome with electrical status epilepticus during slow-wave sleep (ESES). Mutations in the solute carrier family 9, subfamily A member 6 (SLC9A6) gene, encoding the endosomal Na+/H+ exchanger 6 (NHE6) are associated with Christianson syndrome, a syndromic form of X-linked intellectual disability characterized by microcephaly, severe global developmental delay, autistic behavior, early onset seizures and ataxia. In a 7-year-old boy with characteristic clinical and neuroimaging features of Christianson syndrome and epileptic encephalopathy with continuous spikes and waves during sleep, we identified a novel splice site mutation (IVS10-1G>A) in SLC9A6. These findings expand the clinical spectrum of the syndrome and indicate NHE6 dysfunction as a new cause of electrical status epilepticus during slow-wave sleep (ESES).
Which syndrome is NHE6 associated with?
56d860ad51531f7e33000002_002
{ "answer_start": [ 307 ], "text": [ "Christianson syndrome" ] }
A polymorphism study of the human Agouti gene and its association with MC1R. To determine whether the Agouti Signalling Protein (ASP) gene is associated with skin and hair coloration in humans, the complete coding region of ASP was screened for polymorphisms. Analysis of ASP in Caucasian, African-American, Spanish Basque, Hispanic, Apache and Australian Aboriginal populations revealed no amino acid substitutions. A single polymorphism in the 3' untranslated region occurred at a frequency of 0.2 in African-Americans. Variants of the Melanocortin 1 Receptor (MC1R) gene have been found to be associated with red hair and fair skin in humans. Red hair individuals are usually compound heterozygotes or homozygous for one of a number of MC1R polymorphisms associated with red hair. Some individuals however are heterozygous for only one of these polymorphisms and dizygotic twins can be concordant for MC1R variants but discordant for hair colour. A recent study has also identified rare redheads carrying no MC1R variants indicating that polymorphisms of the human MC1R gene are required but not sufficient for the red hair phenotype. To address the question of whether ASP also contributes to the red hair phenotype, individuals previously identified as having unexpected MC1R genotypes were screened for polymorphisms at the ASP locus. No polymorphisms were found in any of these individuals. Results indicate that the human ASP gene is unlikely to function in normal human pigmentation in the same way as MC1R.
Which gene is responsible for red hair?
5ace19420340b9f05800000a_040
{ "answer_start": [ 739 ], "text": [ "MC1R" ] }
Antigenotoxic effects of p53 on spontaneous and ultraviolet light B--induced deletions in the epidermis of gpt delta transgenic mice. Tumor development in the skin may be a multistep process where multiple genetic alterations occur successively. The p53 gene is involved in genome stability and thus is referred to as "the guardian of the genome." To better understand the antigenotoxic effects of p53 in ultraviolet light B (UVB)-induced mutagenesis, mutations were measured in the epidermis of UVB-irradiated p53(+/+) and p53(-/-) gpt delta mice. In the mouse model, point mutations and deletions are separately identified by the gpt and Spi(-) assays, respectively. The mice were exposed to UVB at single doses of 0.5, 1.0, or 2.0 kJ/m(2) . The mutant frequencies (MFs) were determined 4 weeks after the irradiation. All doses of UVB irradiation enhanced gpt MFs by about 10 times than that of unirradiated mice. There were no significant differences in gpt MFs and the mutation spectra between p53(+/+) and p53(-/-) mice. The predominant mutations induced by UVB irradiation were G:C to A:T transitions at dipyrimidines. In contrast, in unirradiated p53(-/-) mice, the frequencies of Spi(-) large deletions of more than 1 kb and complex-type deletions with rearrangements were significantly higher than those of the Spi(-) large deletions in p53(+/+) counterparts. The specific Spi(-) mutation frequency of more than 1 kb deletions and complex types increased in a dose-dependent manner in the p53(+/+) mice. However, no increase of such large deletions was observed in irradiated p53(-/-) mice. These results suggest that the antigenotoxic effects of p53 may be specific to deletions and complex-type mutations induced by double-strand breaks in DNA.
Which tumor suppressor is referred to as "the guardian of the genome"?
55421ee7ccca0ce74b000002_038
{ "answer_start": [ 511 ], "text": [ "p53" ] }
Post-dural puncture headache: pathophysiology, prevention and treatment. Post-dural puncture headache (PDPHA) has been a vexing problem for patients undergoing dural puncture for spinal anaesthesia, as a complication of epidural anaesthesia, and after diagnostic lumbar puncture since Bier reported the first case in 1898. This Chapter discusses the pathophysiology of low-pressure headache resulting from leakage of cerebrospinal fluid (CSF) from the subarachnoid to the epidural spaces. Clinical and laboratory research over the last 30 years has shown that use of small-gauge needles, particularly of the pencil-point design, is associated with a lower risk of PDPHA than traditional cutting point needle tips (Quincke-point needles). A careful history can rule out other causes of headache. A positional component of headache is the sine qua non of PDPHA. In high-risk patients (e.g. age < 50 years, post-partum, large-gauge-needle puncture), patients should be offered early (within 24-48 h of dural puncture) epidural blood patch. The optimum volume of blood has been shown to be 12-20 ml for adult patients. Complications of autologous epidural blood patch are rare.
What is the definitive treatment for low pressure headache?
53262cdcd6d3ac6a34000003_007
{ "answer_start": [ 1015 ], "text": [ "epidural blood patch" ] }
A missense mutation in the ZFHX1B gene associated with an atypical Mowat-Wilson syndrome phenotype. Mowat-Wilson syndrome (MWS) is a rare mental retardation-multiple congenital anomalies syndrome associated with typical facial dysmorphism. Patients can show a variety of other anomalies like short stature, microcephaly, Hirschsprung disease, malformations of the brain, seizures, congenital heart defects and urogenital anomalies. Mutations leading to haploinsufficiency of the ZFHX1B gene have been described as the underlying cause of this condition. We report on the clinical findings in a 2(1/2)-year-old boy with some aspects out of the MWS-spectrum in addition to unusual anomalies and a novel missense mutation in the ZFHX1B gene.
Which gene is responsible for the development of the Mowat-Wilson syndrome?
5519113b622b19434500000f_015
{ "answer_start": [ 27 ], "text": [ "ZFHX1B" ] }
Interpreting gaze in Turner syndrome: impaired sensitivity to intention and emotion, but preservation of social cueing. Women with Turner's syndrome (TS), who lack a complete X-chromosome, show an impairment in remembering faces and in classifying "fear" in face images. Could their difficulties extend to the processing of gaze? Three tasks, all of which rely on the ability to make use of the eye-region of a pictured face, are reported. Women with TS were impaired at judging mental state from images of the upper face ("reading the mind in the eyes"). They were also specifically impaired at interpreting "fear" from displays of the eye-region of the face. However, they showed normal susceptibility to direction of gaze as an attentional cue (social cueing), since they were as sensitive as controls to the validity of the cue, under conditions where it should be ignored. In this task, unlike those of reading the upper face for intention or expression, PIQ accounted for a significant amount of individual variance in task performance. The processing of displays of the eye region affording social and affective information is specifically affected in TS. We speculate that amygdala dysfunction is likely to be implicated in this anomalous behaviour. The presence in the female karyotype of two complete X-chromosomes is protective for some socio-cognitive abilities related to the modulation of behaviour by the interpretation of gaze.
What chromosome is affected in Turner's syndrome?
58bca2f302b8c6095300000c_008
{ "answer_start": [ 175 ], "text": [ "X" ] }
Severe progressive obstructive cardiomyopathy and renal tubular dysfunction in Donohue syndrome with decreased insulin receptor autophosphorylation due to a novel INSR mutation. UNLABELLED: Donohue syndrome (leprechaunism; OMIM *246200) is a rare, recessively inherited disorder of extreme insulin resistance due to mutations in the insulin receptor gene (INSR) causing either defects in insulin binding or receptor autophosphorylation and tyrosine kinase activity. We report a patient with pronounced clinical picture of leprechaunism who developed severe progressive hypertrophic obstructive cardiomyopathy (HOCM) and renal tubular dysfunction which improved on continuous subcutaneous infusion of recombinant human insulin-like growth factor-1 (rhIGF-I). INSR gene molecular analysis and insulin receptor (IR) autophosphorylation on cultured fibroblasts were performed. A novel homozygous missense mutation p.Leu795Pro was found, located in the extracellular portion of the β subunit of the insulin receptor. The post-binding defect of the insulin receptor signaling in cultured fibroblasts demonstrated decreased insulin receptor autophosphorylation. CONCLUSION: Treatment with rhIGF-I partially reversed severe progressive HOCM and renal tubular dysfunction in a patient with Donohue syndrome associated with a novel p.Leu795Pro INSR gene mutation causing a severe decrease in IR autophosphorylation.
Which hormone receptor function is altered in patients with Donohue syndrome?
5314bd7ddae131f847000006_003
{ "answer_start": [ 111 ], "text": [ "insulin receptor" ] }
Alpha- and beta-synuclein expression in Parkinson disease with and without dementia. Parkinson disease (PD) is the most important movement disorder and about 50% of patients develop dementia over the time. PD belongs to the group of Lewy body disorders. Alpha-synuclein (AS) is the main component of Lewy bodies and its aggregation is a key event in the pathogenesis of PD. Beta-synuclein (BS) inhibits AS aggregation in vitro and in vivo and has been shown to interact directly with AS regulating its functionality and preventing its oligomerization. Recently, we have described a molecular subgroup of DLB characterized by the drastic BS reduction in cortical areas. In this study we have analyzed the expression of two BS transcripts and the main AS transcript SNCA140, in frozen samples of three brain areas, temporal cortex, caudate nucleus and pons, from patients with PD and PDD in comparison with controls. Relative mRNA expression was determined by real-time PCR with SybrGreen, neuron-specific-enolase as housekeeping gene and the deltadeltaCt method. The most important difference in BS and AS mRNA expression between PD and PDD was found in the caudate nucleus, where BS mRNA was overexpressed in PD and AS mRNA diminished in PDD. Our findings provide new insights into the pathogenesis of dementia in PD, indicating that differential BS and AS expression in the caudate nucleus may represent one of the molecular mechanisms involved in these complex diseases.
What is the main component of the Lewy bodies?
550c3d45a103b78016000008_024
{ "answer_start": [ 254 ], "text": [ "Alpha-synuclein" ] }
Principles of hand ontogenesis in man. Human hand anlagen of different developmental stages are studied light and scanning electron microscopically. The findings are compared with experimental and ultrastructural results obtained from avian limb anlagen. Shaping, cell differentiation and the spatial arrangement of different cells are found to be the basic processes of hand development. The shaping of the arm and hand seems to anticipate future grasping movements. Factors controlling this developmental process are on the one hand the apical ectodermal ridge (AER) that maintains in the underlying mesoderm a high level of mitotic activity, and on the other hand a species-specific pattern of cell death in different zones of arm and hand. Interdigital cell death, microfilament bundles included in the basal compartment of AER cells, and local anchorings of the AER ectoderm by collagen fibrils are involved in finger separation. The flexion creases are genetically fixed and their development cannot be explained by mechanical factors. It is found that the early hand anlage is already composed of relatively autonomous founder cells committed to different lineages. This is true for the muscle precursor cells which originate from the brachial somites. These migrating somite cells are determined to belong to the myogenic lineage. However, their distribution, mitotic activity and later arrangement in single muscles are controlled by factors localized within the hand itself. Tendons develop autonomously from somatopleural cells. Other already committed cells are the angioblasts forming the endothelial lining of the blood vessels, the neural crest cells differentiating into melanocytes and Schwann cells, and the blood-derived cells like chrondro- or osteoclasts. The differentiation of somatopleural cells into cartilage, connective tissue or smooth muscle depends on their position within the hand anlage. Possible mechanisms leading to the specific pattern are discussed.
Where do the Schwann cells and melanocytes originate from?
58b56fe422d3005309000007_006
{ "answer_start": [ 1647 ], "text": [ "neural crest cells" ] }
Donohue syndrome in a neonate with homozygous deletion of exon 3 of the insulin receptor gene. Donohue syndrome describes the clinical consequences of the most severe genetic loss of insulin receptor function. The cardinal features are severe linear growth impairment pre- and postnatally with abnormal glucose metabolism and a characteristic pattern of soft tissue overgrowth. We report a 5 day old neonate with refractory hyperglycemia and paradoxical hypoglycemia, severe intrauterine growth retardation, typical 'elfin' facies (hypertrichosis, large and low-set ears, broad nasal tip, flared nares, thick lips), reduced subcutaneous fat, distended abdomen, and enlarged external genitalia and nipples. Fasting serum insulin and C-peptide were severely elevated at >2,100 pmol/l and >2,331 pmol/l, respectively. In addition, hepatic, ovarian and renal enlargement was demonstrated by ultrasonography. The neonate died within two months secondary to hypoglycemia. Diplex PCR analysis of the insulin receptor gene revealed the neonate to be homozygous for deletion of exon 3. Both parents were heterozygous for this deletion but were metabolically healthy. As such a deletion has previously been reported in Israel, we suggest that it may show a founder effect in the Middle East.
Which hormone receptor function is altered in patients with Donohue syndrome?
5314bd7ddae131f847000006_010
{ "answer_start": [ 72 ], "text": [ "insulin receptor" ] }
A randomized evaluation of betrixaban, an oral factor Xa inhibitor, for prevention of thromboembolic events after total knee replacement (EXPERT). Betrixaban is an oral direct inhibitor of factor Xa (FXa) being developed for the prevention of venous thromboembolism (VTE). Its antithrombotic effects had not been previously tested in patients. This exploratory clinical trial in the US and Canada randomized 215 patients undergoing elective total knee replacement (TKR) in a 2:2:1 ratio to receive post-operative betrixaban 15 mg or 40 mg p.o. bid or enoxaparin 30 mg s.c. q12h, respectively, for 10-14 days. The betrixaban dosage was blinded, but enoxaparin was not. Primary efficacy outcome was the incidence of VTE, consisting of deep-vein thrombosis (DVT) on mandatory unilateral (operated leg) venography, symptomatic proximal DVT, or pulmonary embolism (PE) through Day 10-14. Safety outcomes included major and clinically significant non-major bleeds through 48 h after treatment. All efficacy and bleeding outcomes were adjudicated by a blinded independent central adjudication committee. Of 214 treated patients, 175 (82%) were evaluable for primary efficacy. VTE incidence was 14/70 (20%; 95% CI: 11, 31) for betrixaban 15 mg, 10/65 (15%; 95% CI: 8, 27) for betrixaban 40 mg, and 4/40 (10%; 95% CI: 3, 24) for enoxaparin. No bleeds were reported for betrixaban 15 mg, 2 (2.4%) clinically significant non-major bleeds with betrixaban 40 mg, and one (2.3%) major and two (4.6%) clinically significant non-major bleeds with enoxaparin. A dose- and concentration-dependent effect of betrixaban on inhibition of thrombin generation and anti-Xa levels was observed. Betrixaban demonstrated antithrombotic activity and appeared well tolerated in knee replacement patients at the doses studied.
Which clotting factor is inhibited by betrixaban?
55200c606b348bb82c000013_088
{ "answer_start": [ 196 ], "text": [ "Xa" ] }
Use of flumazenil in the treatment of drug overdose: a double-blind and open clinical study in 110 patients. OBJECTIVES: To assess the efficacy, usefulness, safety, and dosages of flumazenil required when flumazenil is used in the diagnosis of benzodiazepine-induced coma (vs. other drug-induced coma), and to reverse or prevent the recurrence of unconsciousness. DESIGN: A two-phase study: a controlled, randomized, double-blind study followed by a prospective, open study. SETTING: An 800-bed, teaching, university-affiliated hospital. PATIENTS: Unconscious patients (n = 110) suspected of benzodiazepine overdose, graded 2 to 4 on the Matthew and Lawson coma scale, were treated with flumazenil, the specific benzodiazepine receptor antagonist. The first 31 patients were studied in a double-blind fashion, while the rest of the patients were given flumazenil according to an open protocol. INTERVENTIONS; All patients received supplemental oxygen; endotracheal intubation was performed, and synchronized intermittent mandatory ventilation was initiated whenever it was deemed necessary. A peripheral intravenous cannula was inserted, as were indwelling arterial and urinary bladder catheters. Blood pressure, electrocardiogram, respiratory rate, end-tidal CO2, and core temperature were continuously monitored. The first 31 double-blind patients received either intravenous flumazenil (to a maximum of 1 mg) or saline, while the rest of the patients were given flumazenil until either regaining consciousness or a maximum of 2.5 mg was injected. Patients remaining unconscious among double-blind patients or those patients relapsing into coma after the first dose were later treated in the open phase of the study. Treatment continued by boluses or infusion as long as efficacious. MEASUREMENTS AND MAIN RESULTS: Fourteen of 17 double-blind, flumazenil-treated patients woke after a mean of 0.8 +/- 0.3 (SD) mg vs. one of 14 placebo patients (p < .001). Seventy-five percent of the aggregated controlled and uncontrolled patients awoke from coma scores of 3.1 +/- 0.6 to 0.4 +/- 0.5 (p < .01) after the injection of 0.7 +/- 0.3 mg of flumazenil. These patients had high benzodiazepine serum blood concentrations. Twenty-five percent of the patients did not regain consciousness. These patients had very high serum concentrations of nonbenzodiazepine drugs. Sixty percent of the responders who had primarily ingested benzodiazepines remained awake for 72 +/- 37 mins after flumazenil administration; 40% relapsed into coma after 18 +/- 7 mins and various central nervous system depressant drugs were detected in their blood in addition to benzodiazepines. Seventy-one percent of the patients had ingested tricyclic antidepressants. Seventy-eight percent of the responders were continually and efficaciously treated for < or = 8 days. Fourteen (25%) of the intubated patients were extubated safely while 12 patients, who had shown increased respiratory insufficiency, resumed satisfactory respiration after flumazenil injection. Five cases of transient increase in blood pressure and heart rate were encountered. There were 27 mildly unpleasant "waking" episodes, such as anxiety, restlessness, and aggression, but no patient had benzodiazepine withdrawal signs, convulsions, or dysrhythmia, most noticeably absent in tricyclic antidepressant-intoxicated patients. CONCLUSIONS: Flumazenil is a valid diagnostic tool for distinguishing pure benzodiazepine from mixed-drug intoxication or nondrug-induced coma. Flumazenil is effective in preventing recurrence of benzodiazepine-induced coma. Respiratory insufficiency is reversed after its administration. Flumazenil is safe when administered cautiously, even in patients with coma caused by a mixed overdose of benzodiazepine plus tricyclic antidepressants.
Which drug should be used as an antidote in benzodiazepine overdose?
514a0a57d24251bc05000051_040
{ "answer_start": [ 3656 ], "text": [ "Flumazenil" ] }
First example of anti-Kx in a person with the McLeod phenotype and without chronic granulomatous disease. BACKGROUND: Kx is lacking in the RBCs of patients with the McLeod syndrome. This condition is sometimes associated with chronic granulomatous disease (CGD). If given allogeneic RBCs, CGD patients with the McLeod phenotype may produce anti-Kx and anti-Km, and only phenotypically matched McLeod blood would be compatible. McLeod phenotype persons without CGD have made anti-Km but not anti-Kx (2 examples), and thus both McLeod and K(O) blood would be compatible. CASE REPORT: RBCs from a transfused patient with the McLeod phenotype but not with CGD (non-CGD McLeod) were typed for the Kell blood group antigens, and the plasma was analyzed for the presence of antibody by agglutination. The molecular basis was determined by analyzing for XK protein on RBC membranes by Western immunoblotting, by sequencing the XK gene, and by RFLP. RESULTS: The RBCs did not react with anti-Kx + anti-Km and showed weakening of Kell system antigens. The patient's plasma reacted moderately (2+) with RBCs of common Kell type and strongly (4+) with K(O) RBCs and RBCs of common Kell type treated with dithiothreitol, and did not react with McLeod RBCs. XK protein was absent from the RBC membranes. The XK gene had a point mutation in the donor splice site of intron 1 (G>C). CONCLUSION: This is the first report describing the molecular alteration in a non-CGD McLeod patient who has made anti-Kx. The immune response of people with the McLeod phenotype can vary, and K(O) blood may not always be compatible.
Mutation of which gene is associated with McLeod syndrome?
531464a6e3eabad021000014_056
{ "answer_start": [ 1294 ], "text": [ "XK" ] }
In vitro characterization of mutant yeast RNA polymerase II with reduced binding for elongation factor TFIIS. We have reported previously the isolation and genetic characterization of mutations in the gene encoding the largest subunit of yeast RNA polymerase II (RNAPII), which lead to 6-azauracil (6AU)-sensitive growth. It was suggested that these mutations affect the functional interaction between RNAPII and transcription-elongation factor TFIIS because the 6AU-sensitive phenotype of the mutant strains was similar to that of a strain defective in the production of TFIIS and can be suppressed by increasing the dosage of the yeast TFIIS-encoding gene, PPR2, RNAPIIs were purified and characterized from two independent 6AU-sensitive yeast mutants and from wild-type (wt) cells. In vitro, in the absence of TFIIS, the purified wt polymerase and the two mutant polymerases showed similar specific activity in polymerization, readthrough at intrinsic transcriptional arrest sites and nascent RNA cleavage. In contrast to the wt polymerase, both mutant polymerases were not stimulated by the addition of a 3-fold molar excess of TFIIS in assays of promoter-independent transcription, readthrough or cleavage. However, stimulation of the ability of the mutant RNAPIIs to cleave nascent RNA and to read through intrinsic arrest sites was observed at TFIIS:RNAPII molar ratios greater than 600:1. Consistent with these findings, the binding affinity of the mutant polymerases for TFIIS was found to be reduced by more than 50-fold compared with that of the wt enzyme. These studies demonstrate that TFIIS has an important role in the regulation of transcription by yeast RNAPII and identify a possible binding site for TFIIS on RNAPII.
Which RNA polymerase II subunit carries RNA cleavage activity?
5a4df811966455904c00000e_004
{ "answer_start": [ 103 ], "text": [ "TFIIS" ] }
Methods to study transcription-coupled repair in chromatin. Transcription-coupled repair (TCR) is a sub-pathway of nucleotide excision repair that allows for the enhanced repair of the transcribed strand of active genes. A classical method to study DNA repair in vivo consists in the molecular analysis of UV-induced DNA damages at specific loci. Cells are irradiated with a defined dose of UV light leading to the formation of DNA lesions and incubated in the dark to allow repair. About 90% of the photoproducts consist of cyclobutane pyrimidine dimers, which can be cleaved by the DNA nicking activity of the T4 endonuclease V (T4endoV) repair enzyme. Strand-specific repair in a suitable restriction fragment is determined by alkaline gel electrophoresis followed by Southern blot transfer and indirect end-labeling using a single-stranded probe. Recent approaches have assessed the role of transcription factors in TCR by analyzing RNA polymerase II occupancy on a damaged template by chromatin immunoprecipitation (ChIP). Cells are treated with formaldehyde in vivo to cross-link proteins to DNA and enrichment of a protein of interest is done by subsequent immunoprecipitation. Upon reversal of the protein-DNA cross-links, the amount of coprecipitated DNA fragments can be detected by quantitative PCR. To perform ChIP on UV-damaged templates, we included an in vitro photoreactivation step prior to PCR analysis to ensure that all precipitated DNA fragments serve as substrates for the PCR reaction. Here, we provide a detailed protocol for both the DNA repair analysis and the ChIP approaches to study TCR in chromatin.
Which gene strand is targeted by transcription-coupled repair (TCR)?
5545186cbf90a13052000002_004
{ "answer_start": [ 181 ], "text": [ "the transcribed strand" ] }
Transcriptional regulation by MAP kinases. Tyrosine kinase growth factor receptors activate MAP kinase by a complex mechanism involving the SH2/3 protein Grb2, the exchange protein Sos, and Ras. The GTP-bound Ras protein binds to the Raf kinase and initiates a protein kinase cascade that leads to MAP kinase activation. Three MAP kinase kinase kinases have been described--c-Raf, c-Mos, and Mekk--that phosphorylate and activate Mek, the MAP kinase kinase. Activated Mek phosphorylates and activates MAP kinase. Subsequently, the activated MAP kinase translocates into the nucleus where many of the physiological targets of the MAP kinase signal transduction pathway are located. These substrates include transcription factors that are regulated by MAP kinase phosphorylation (e.g., Elk-1, c-Myc, c-Jun, c-Fos, and C/EBP beta). Thus the MAP kinase pathway represents a significant mechanism of signal transduction by growth factor receptors from the cell surface to the nucleus that results in the regulation of gene expression. Three MAP kinase homologs have been identified in the rat: Erk1, Erk2, and Erk3. Human MAP kinases that are similar to the rat Erk kinases have also been identified by molecular cloning. The human Erk1 protein kinase has been shown to be widely expressed as a 44-kDa protein in many tissues. The human Erk2 protein kinase is a 41-kDa protein that is expressed ubiquitously. In contrast, a human Erk3-related protein kinase has been found to be expressed at a high level only in heart muscle and brain. The loci of these MAP kinase genes are widely distributed within the human genome: erk2 at 22q11.2; erk1 at 16p11.2; and ek3-related at 18q12-21. In the yeast Saccharomyces cerevisiae, five MAP kinase gene homologs have been described: smkl, mpk1, hog1, fus3, and kss1. Together, these kinases are a more diverse group than the human erks that have been identified. Thus the erks are likely to represent only one subgroup of a larger human MAP kinase gene family. A candidate for this extended family of MAP kinases is the c-Jun NH2-terminal kinase (Jnk), which binds to and phosphorylates the transcription factor c-Jun at the activating sites Ser-63 and Ser-73. Evidence is presented here to demonstrate that Jnk is a distant relative of the MAP kinase group that is activated by dual phosphorylation at Tyr and Thr.
Which MAP kinase phosphorylates the transcription factor c-jun?
5518e7da622b194345000004_023
{ "answer_start": [ 2082 ], "text": [ "Jnk" ] }
Emerging anticoagulants. Warfarin, heparin and their derivatives have been the traditional anticoagulants used for prophylaxis and treatment of venous thromboembolism. While the modern clinician is familiar with the efficacy and pharmacokinetics of these agents, their adverse effects have provided the impetus for the development of newer anticoagulants with improved safety, ease of administration, more predictable pharmacodynamics and comparable efficacy. Research into haemostasis and the coagulation cascade has made the development of these newer anticoagulants possible. These drugs include the factor Xa inhibitors and IIa (thrombin) inhibitors. Direct and indirect factor Xa inhibitors are being developed with a relative rapid onset of action and stable pharmacokinetic profiles negating the need for close monitoring; this potentially makes them a more attractive option than heparin or warfarin. Examples of direct factor Xa inhibitors include apixaban, rivaroxaban, otamixaban, betrixaban and edoxaban. Examples of indirect factor Xa inhibitors include fondaparinux, idraparinux and idrabiotaparinux. Direct thrombin inhibitors (factor IIa inhibitors) were developed with the limitations of standard heparin and warfarin in mind. Examples include recombinant hirudin (lepirudin), bivalirudin, ximelagatran, argatroban, and dabigatran etexilate. This review will discuss emerging novel anticoagulants and their use for the prophylaxis and management of venous thromboembolism, for stroke prevention in nonvalvular atrial fibrillation and for coronary artery disease.
Which clotting factor is inhibited by betrixaban?
55200c606b348bb82c000013_042
{ "answer_start": [ 985 ], "text": [ "xa" ] }
Cathepsin A regulates chaperone-mediated autophagy through cleavage of the lysosomal receptor. Protective protein/cathepsin A (PPCA) has a serine carboxypeptidase activity of unknown physiological function. We now demonstrate that this protease activity triggers the degradation of the lysosome-associated membrane protein type 2a (lamp2a), a receptor for chaperone-mediated autophagy (CMA). Degradation of lamp2a is important because its level in the lysosomal membrane is a rate-limiting step of CMA. Cells defective in PPCA show reduced rates of lamp2a degradation, higher levels of lamp2a and higher rates of CMA. Restoration of PPCA protease activity increases rates of lamp2a degradation, reduces levels of lysosomal lamp2a and reduces rates of CMA. PPCA associates with lamp2a on the lysosomal membrane and cleaves lamp2a near the boundary between the luminal and transmembrane domains. In addition to the well-studied role of PPCA in targeting and protecting two lysosomal glycosidases, we have defined a role for the proteolytic activity of this multifunctional protein.
Which is the receptor for substrates of Chaperone Mediated Autophagy?
51bdd9c2047fa84d1d000002_001
{ "answer_start": [ 332 ], "text": [ "lamp2a" ] }
Ehlers-Danlos syndrome and periventricular nodular heterotopia in a Spanish family with a single FLNA mutation. BACKGROUND: The Ehlers-Danlos syndrome (EDS) comprises a group of hereditary connective tissue disorders. Periventricular nodular heterotopia (PNH) is a human neuronal migration disorder characterised by seizures and conglomerates of neural cells around the lateral ventricles of the brain, caused by FLNA mutations. FLNA encodes filamin A, an actin binding protein involved in cytoskeletal organisation. The amino-terminal actin binding domain (ABD) of filamins contains two tandem calponin homology domains, CHD1 and CHD2. OBJECTIVE: To report clinical and genetic analyses in a Spanish family affected by a connective tissue disorder suggestive of EDS type III and PNH. METHODS: A clinical and molecular study was undertaken in the three affected women. Clinical histories, physical and neurological examinations, brain magnetic resonance imaging studies, and skin biopsies were done. Genetic analysis of the FLNA gene was undertaken by direct sequencing and restriction fragment length polymorphism analysis. RESULTS: Mutation analysis of the FLNA gene resulted in the identification of a novel mutation in exon 3 (c.383C-->T) segregating with the combination of both syndromes. This mutation results in a substitution of an alanine residue (A128V) in CHD1. CONCLUSIONS: The findings suggest that the Ala128Val mutation causes the dual EDS-PNH phenotype. This association constitutes a new variant within the EDS spectrum. This is the first description of a familial EDS-PNH association with a mutation in FLNA.
What tissue is most affected in Ehlers-Danlos syndromes?
58cdb41302b8c60953000042_018
{ "answer_start": [ 189 ], "text": [ "connective tissue" ] }
Orteronel (TAK-700), a novel non-steroidal 17,20-lyase inhibitor: effects on steroid synthesis in human and monkey adrenal cells and serum steroid levels in cynomolgus monkeys. Surgical or pharmacologic methods to control gonadal androgen biosynthesis are effective approaches in the treatment of a variety of non-neoplastic and neoplastic diseases. For example, androgen ablation and its consequent reduction in circulating levels of testosterone is an effective therapy for advanced prostate cancers. Unfortunately, the therapeutic effectiveness of this approach is often temporary because of disease progression to the 'castration resistant' (CRPC) state, a situation for which there are limited treatment options. One mechanism thought to be responsible for the development of CRPC is extra-gonadal androgen synthesis and the resulting impact of these residual extra-gonadal androgens on prostate tumor cell proliferation. An important enzyme responsible for the synthesis of extra-gonadal androgens is CYP17A1 which possesses both 17,20-lyase and 17-hydroxylase catalytic activities with the 17,20-lyase activity being key in the androgen biosynthetic process. Orteronel (TAK-700), a novel, selective, and potent inhibitor of 17,20-lyase is under development as a drug to inhibit androgen synthesis. In this study, we quantified the inhibitory activity and specificity of orteronel for testicular and adrenal androgen production by evaluating its effects on CYP17A1 enzymatic activity, steroid production in monkey adrenal cells and human adrenal tumor cells, and serum levels of dehydroepiandrosterone (DHEA), cortisol, and testosterone after oral dosing in castrated and intact male cynomolgus monkeys. We report that orteronel potently suppresses androgen production in monkey adrenal cells but only weakly suppresses corticosterone and aldosterone production; the IC(50) value of orteronel for cortisol was ~3-fold higher than that for DHEA. After single oral dosing, serum levels of DHEA, cortisol, and testosterone were rapidly suppressed in intact cynomolgus monkeys. In castrated monkeys treated twice daily with orteronel, suppression of DHEA and testosterone persisted throughout the treatment period. In both in vivo models and in agreement with our in vitro data, suppression of serum cortisol levels following oral dosing was less than that seen for DHEA. In terms of human CYP17A1 and human adrenal tumor cells, orteronel inhibited 17,20-lyase activity 5.4 times more potently than 17-hydroxylase activity in cell-free enzyme assays and DHEA production 27 times more potently than cortisol production in human adrenal tumor cells, suggesting greater specificity of inhibition between 17,20-lyase and 17-hydroxylase activities in humans vs monkeys. In summary, orteronel potently inhibited the 17,20-lyase activity of monkey and human CYP17A1 and reduced serum androgen levels in vivo in monkeys. These findings suggest that orteronel may be an effective therapeutic option for diseases where androgen suppression is critical, such as androgen sensitive and CRPC.
Which enzyme is inhibited by Orteronel?
54e0c3e71388e8454a000013_011
{ "answer_start": [ 2853 ], "text": [ "CYP17A1" ] }
Emerging anticoagulants. Warfarin, heparin and their derivatives have been the traditional anticoagulants used for prophylaxis and treatment of venous thromboembolism. While the modern clinician is familiar with the efficacy and pharmacokinetics of these agents, their adverse effects have provided the impetus for the development of newer anticoagulants with improved safety, ease of administration, more predictable pharmacodynamics and comparable efficacy. Research into haemostasis and the coagulation cascade has made the development of these newer anticoagulants possible. These drugs include the factor Xa inhibitors and IIa (thrombin) inhibitors. Direct and indirect factor Xa inhibitors are being developed with a relative rapid onset of action and stable pharmacokinetic profiles negating the need for close monitoring; this potentially makes them a more attractive option than heparin or warfarin. Examples of direct factor Xa inhibitors include apixaban, rivaroxaban, otamixaban, betrixaban and edoxaban. Examples of indirect factor Xa inhibitors include fondaparinux, idraparinux and idrabiotaparinux. Direct thrombin inhibitors (factor IIa inhibitors) were developed with the limitations of standard heparin and warfarin in mind. Examples include recombinant hirudin (lepirudin), bivalirudin, ximelagatran, argatroban, and dabigatran etexilate. This review will discuss emerging novel anticoagulants and their use for the prophylaxis and management of venous thromboembolism, for stroke prevention in nonvalvular atrial fibrillation and for coronary artery disease.
Which clotting factor is inhibited by betrixaban?
55200c606b348bb82c000013_102
{ "answer_start": [ 960 ], "text": [ "xa" ] }
Phosphorylation-mediated inactivation of coactivator-associated arginine methyltransferase 1. Multiple protein arginine methyltransferases are involved in transcriptional activation of nuclear receptors. Coactivator-associated arginine methyltransferase 1 (CARM1)-mediated histone methylation has been shown to activate nuclear receptor-dependent transcription; however, little is known about the regulation of its enzymatic activity. Here, we report that the methyltransferase activity of CARM1 is negatively regulated through phosphorylation at a conserved serine residue. When the serine residue is mutated to glutamic acid, which mimics the phosphorylated serine residue, the mutant CARM1 exhibits diminished ability to bind the methyl donor adenosylmethionine and diminished histone methylation activity. Moreover, such mutation leads to the inhibition of CARM1 transactivation of estrogen receptor-dependent transcription. Our results provide an example for the regulation of protein arginine methyltransferase activity by phosphorylation. As CARM1 is a potent transcriptional coactivator of estrogen receptor, our results suggest that phosphorylation of CARM1 serves as a unique mechanism for inactivating CARM1-regulated estrogen-dependent gene expression.
Which is the methyl donor of histone methyltransferases?
516e7fda298dcd4e51000081_012
{ "answer_start": [ 746 ], "text": [ "adenosylmethionine" ] }
Characterization of radioactive metabolites of 5-HT2A receptor PET ligand [18F]altanserin in human and rodent. This study was performed to identify and characterize the radiometabolites of the serotonin 5-HT2A receptor ligand [18F]altanserin in supporting quantification of the target receptors by positron emission tomography. In analogy to its analog ketanserin, we postulated 4-(4-fluorobenzoyl)piperidine (FBP) and altanserinol for the previously observed two polar radiometabolites, corresponding to dealkylation at the piperidine nitrogen and reduction at the ketone, respectively. To test this hypothesis and characterize the in vivo and in vitro behavior of the radiometabolites, we synthesized nonradioactive authentic compounds altanserinol, 1-(4-fluorophenyl)-1-(piperidin-4-yl)methanol (FBPOH), and isolated nonradioactive FBP metabolite from monkey plasma. [18F]Altanserinol was obtained by NaBH4 reduction of [18F]altanserin, followed by acid hydrolysis. Identification of radiometabolites was carried out by high performance liquid chromatography and thin layer chromatography comparison of the radioactive plasma after injection of tracers with five authentic compounds. Human studies revealed that at least four radiometabolites, one identified as [18F]altanserinol, resulted from reduction of the ketone functionality. The N-dealkylation product [18F]FBP was not detectable; however, a radiometabolite of FBP was present in plasma after administration of [18F]altanserin. Monkey studies showed nonradioactive FBP was converted rapidly to a less polar metabolite. In rat, altanserin and altanserinol were converted to each other in vivo, and all the radiometabolites likely penetrated the blood-brain barrier and entered the brain. Displacement binding of altanserin to cloned serotonin 5-HT2A, 5-HT2C, 5-HT6, and 5-HT7 receptors showed Ki values of 0.3, 6.0, 1,756, and 15 nM; the binding of FBP and altanserinol to these four 5-HT subtypes was negligible. We conclude from these studies that the radiometabolites of [18F]altanserin from N-dealkylation and ketone reduction should not interfere with specific receptor quantification in an equilibrium paradigm.
Which receptors can be evaluated with the [18F]altanserin?
55242d512c8b63434a000006_023
{ "answer_start": [ 203 ], "text": [ "5-HT2A" ] }