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Which web-based pedigree editors are available? | Pedigreejs and Madeline 2.0 Pedigree Drawing Engine (PDE) | The Madeline 2.0 Pedigree Drawing Engine (PDE) is a pedigree drawing program for
use in linkage and family-based association studies. The program is designed to
handle large and complex pedigrees with an emphasis on readability and
aesthetics. For complex pedigrees, we use a hybrid algorithm in which
consanguinous loops are drawn as cyclic graphs whenever possible, but we resort
to acyclic graphs when matings can no longer be connected without line
crossings. A similar hybrid approach is used to avoid line crossings for matings
between distant descendants of different founding groups. Written in
object-oriented C++ and released under the GNU General Public License (GPL),
Madeline 2.0 PDE reads input files specified on the command line and generates
pedigree drawings without user interaction. Pedigree output in scalable vector
graphics (SVG) format can be viewed in browsers with native SVG rendering
support or in vector graphics editors. We provide an easy-to-use public web
service, which is experimental and still under development.
AVAILABILITY: http://kellogg.umich.edu/madeline. |
What is the mechanism of action of Solriamfetol? | Solriamfetol is a selective norepinephrine-dopamine reuptake inhibitor. It is used to treat excessive sleepiness in obstructive sleep apnea and narcolepsy patients. | Excessive sleepiness (ES) is associated with several sleep disorders, including
narcolepsy and obstructive sleep apnea (OSA). A role for monoaminergic systems
in treating these conditions is highlighted by the clinical use of US Food and
Drug Administration-approved drugs that act on these systems, such as
dextroamphetamine, methylphenidate, modafinil, and armodafinil. Solriamfetol
(JZP-110) is a wake-promoting agent that is currently being evaluated to treat
ES in patients with narcolepsy or OSA. Clinical and preclinical data suggest
that the wake-promoting effects of solriamfetol differ from medications such as
modafinil and amphetamine. The goal of the current studies was to characterize
the mechanism of action of solriamfetol at monoamine transporters using in vitro
and in vivo assays. Results indicate that solriamfetol has dual reuptake
inhibition activity at dopamine (DA; IC50 = 2.9 μM) and norepinephrine (NE; IC50
= 4.4 μM) transporters, and this activity is associated in vivo with increased
extracellular concentration of DA and NE as measured by microdialysis.
Solriamfetol has negligible functional activity at the serotonin transporter
(IC50 > 100 μM). Moreover, the wake-promoting effects of solriamfetol are
probably owing to activity at DA and NE transporters rather than other
neurotransmitter systems, such as histamine or orexin. The dual activity of
solriamfetol at DA and NE transporters and the lack of significant
monoamine-releasing properties of solriamfetol might explain the differences in
the in vivo effects of solriamfetol compared with modafinil or amphetamine.
Taken together, these data suggest that solriamfetol may offer an important
advancement in the treatment of ES in patients with narcolepsy or OSA. Introduction: Obstructive sleep apnea (OSA) is highly prevalent and constitutes
a major health hazard. Current pharmacotherapy is ineffective in correcting
sleep-disordered breathing and is used adjunctively to address residual
sleepiness. A new drug, solriamfetol, a selective norepinephrine-dopamine
reuptake inhibitor, is the first drug of its class that is being considered by
the US Food and Drug Administration (FDA) to treat excessive sleepiness in OSA
and narcolepsy patients. Areas covered: This review covers drug chemistry,
pharmacodynamics, pharmacokinetics, and metabolism of solriamfetol. Results of
three Phase 3 trials, Treatment of OSA and Narcolepsy Excessive Sleepiness
(TONES 3, 4, 5), relevant to OSA patients are summarized. Published
abstracts/articles and a 2017 Jazz Investor Presentation provided data.
Databases searched included PubMed, Google Scholar, Lexi-Comp, Scopus, Science,
and Ovid. Expert commentary: Solriamfetol shows promise as adjunctive therapy in
OSA. It is well tolerated and effective in reducing sleepiness and is an
alternative to modafinil or armodafinil. Unlike stimulants like methylphenidate
or dextroamphetamine, it does not have cardiac effects, rebound hypersomnia, or
withdrawal effects. |
What is the difference between the nuclease Cas13a and C2c2 | Cas13a was previously called C2c2. | Application of the bacterial CRISPR/Cas systems to eukaryotes is revolutionizing
biology. Cas9 and Cas12 (previously called Cpf1) are widely used as DNA
nucleases for inducing site-specific DNA breaks for different kinds of genome
engineering applications, and in their mutated forms as DNA-binding proteins to
modify gene expression. Moreover, histone modifications, as well as cytosine
methylation or base editing, were achieved with these systems in plants.
Recently, with the discovery of the nuclease Cas13a (previously called C2c2),
molecular biologists have obtained a system that enables sequence-specific
cleavage of single-stranded RNA molecules. The latest experiments with this and
also the alternative Cas13b system demonstrate that these proteins can be used
in a similar manner in eukaryotes for RNA manipulation as Cas9 and Cas12 for DNA
manipulations. The first application of Cas13a for post-transcriptional
regulation of gene expression in plants has been reported. Recent results show
that the system is also applicable for combating viral infection in plants. As
single-stranded RNA viruses are by far the most abundant class of viruses in
plants, the application of this system is of special promise for crops. More
interesting applications are imminent for plant biologists, with nuclease dead
versions of Cas13 enabling the ability to visualize RNA molecules in vivo, as
well as to edit different kinds of RNA molecules at specific bases by
deamination or to modify them by conjugation. Moreover, by combining DNA- and
RNA-directed systems, the most complex of changes in plant metabolism might be
achievable. |
Phlorotannin is extracted from what plant? | Phlorotannin is extracted from Brown Seaweed or brown Algae | A process for the effective extraction and fractionation of phlorotannins from
Fucus vesiculosus with high antioxidant potentials was investigated. The
antioxidant activity of F. vesiculosus extract/fractions was assessed by
2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, reducing power, and
ferrous ion-chelating assays. Among the crude extract and different polarity
fractions, the phlorotannin-enriched ethyl acetate fraction possessed the
highest DPPH scavenging activity and reducing power. This fraction was further
fractionated by Sephadex LH-20 column chromatography or ultrafiltration. The
antioxidant properties were evaluated by both the above chemical antioxidant
tests and a mononuclear cell-based bioassay. Sephadex subfractions LH-2 and LH-3
with high total phlorotannin content exhibited strong DPPH quenching activity,
comparable to those of ascorbic acid and butylated hydroxytoluene and
significantly higher than that of α-tocopherol. Polyphenols in F. vesiculosus
were found to consist mainly of high molecular weight phlorotannin polymers.
There were no clear relationships between the degree of polymerization,
molecular size, and antioxidant activity. All the subfractions separated by
Sephadex LH-20 column chromatography and ultrafiltration showed a high ability
to scavenge reactive oxygen species generated by mononuclear cells. Further
characterization of the phlorotannin compounds was performed on six Sephadex
subfractions. Several phlorotannin oligomers were tentatively identified on the
basis of HPLC-ESI-MS(n) analyses. Phlorotannin is the collective term for polyphenols derived from brown algae
belonging to the genera Ascopyllum, Ecklonia, Eisenia, Fucus and Sargassum etc.
Since the incidence of allergies is currently increasing in the world, there is
a focus on phlorotannins having anti-allergic and anti-inflammatory effects. In
this study, six purified phlorotannins (eckol; 6,6'-bieckol; 6,8'-bieckol;
8,8'-bieckol; phlorofucofuroeckol (PFF)-A and PFF-B) from Eisenia arborea,
orally administered to mice, were examined for their suppression effects on ear
swelling. In considering the suppression, we also examined whether the
phlorotannins suppressed release of chemical mediators (histamine, leukotriene
B₄ and prostaglandin E₂), and mRNA expression and/or the activity of
cyclooxygenase-2 (COX-2), using RBL-2H3 cells, a cultured mast cell model.
Results showed that the phlorotnins exhibited suppression effects in all
experiments, with 6,8'-bieckol, 8,8'-bieckol and PFF-A showing the strongest of
these effects. In conclusion, orally administered phlorotannins suppress mouse
ear swelling, and this mechanism apparently involves suppression of chemical
mediator release and COX-2 mRNA expression or activity. This is the first report
of the anti-allergic effects of the orally administered purified phlorotannins
in vivo. Phlorotannins show potential for use in functional foods or drugs. |
Where are pannexins localized? | Pannexins (Panxs) are a multifaceted family of ion and metabolite channels that play key roles in a number of physiological and pathophysiological settings. These single membrane large-pore channels exhibit a variety of tissue, cell type, and subcellular distributions. | Pannexins (Panxs) are a multifaceted family of ion and metabolite channels that
play key roles in a number of physiological and pathophysiological settings.
These single membrane large-pore channels exhibit a variety of tissue, cell
type, and subcellular distributions. The lifecycles of Panxs are complex, yet
must be understood to accurately target these proteins for future therapeutic
use. Here we review the basics of Panx function and localization, and then
analyze the recent advances in knowledge regarding Panx trafficking. We examine
several intrinsic features of Panxs including specific post-translational
modifications, the divergent C-termini, and oligomerization, all of which
contribute to Panx anterograde transport pathways. Further, we examine the
potential influence of extrinsic factors, such as protein-protein interactions,
on Panx trafficking. Finally, we highlight what is currently known with respect
to Panx internalization and retrograde transport, and present new data
illustrating Panx1 internalization following an activating stimulus. Pannexins (Panx) are proteins homologous to the invertebrate gap junction
proteins called innexins (Inx) and are traditionally described as transmembrane
channels connecting the intracellular and extracellular compartments. Three
distinct Panx paralogs (Panx1, Panx2 and Panx3) have been identified in
vertebrates but previous reports on Panx expression and functionality focused
primarily on Panx1 and Panx3 proteins. Several gene expression studies reported
that Panx2 transcript is largely restricted to the central nervous system (CNS)
hence suggesting that Panx2 might serve an important role in the CNS. However,
the lack of suitable antibodies prevented the creation of a comprehensive map of
Panx2 protein expression and Panx2 protein localization profile is currently
mostly inferred from the distribution of its transcript. In this study, we
characterized novel commercial monoclonal antibodies and surveyed Panx2
expression and distribution at the mRNA and protein level by real-time qPCR,
Western blotting and immunofluorescence. Panx2 protein levels were readily
detected in every tissue examined, even when transcriptional analysis predicted
very low Panx2 protein expression. Furthermore, our results indicate that Panx2
transcriptional activity is a poor predictor of Panx2 protein abundance and does
not correlate with Panx2 protein levels. Despite showing disproportionately high
transcript levels, the CNS expressed less Panx2 protein than any other tissues
analyzed. Additionally, we showed that Panx2 protein does not localize at the
plasma membrane like other gap junction proteins but remains confined within
cytoplasmic compartments. Overall, our results demonstrate that the endogenous
expression of Panx2 protein is not restricted to the CNS and is more ubiquitous
than initially predicted. Pannexins (Panx) are proteins with a similar membrane topology to connexins, the
integral membrane protein of gap junctions. Panx1 channels are generally of
major importance in a large number of system and cellular processes and their
function has been thoroughly characterized. In contrast, little is known about
channel structure and subcellular distribution. We therefore determine the
subcellular localization of Panx1 channels in cultured cells and aim at the
identification of channel morphology in vitro. Using freeze-fracture replica
immunolabeling on EYFP-Panx1-overexpressing HEK 293 cells, large particles were
identified in plasma membranes, which were immunogold-labeled using either GFP
or Panx1 antibodies. There was no labeling or particles in the nuclear membranes
of these cells, pointing to plasma membrane localization of Panx1-EYFP channels.
The assembly of particles was irregular, this being in contrast to the regular
pattern of gap junctions. The fact that no counterparts were identified on
apposing cells, which would have been indicative of intercellular signaling,
supported the idea of Panx1 channels within one membrane. Control cells
(transfected with EYFP only, non-transfected) were devoid of both particles and
immunogold labeling. Altogether, this study provides the first demonstration of
Panx1 channel morphology and assembly in intact cells. The identification of
Panx1 channels as large particles within the plasma membrane provides the
knowledge required to enable recognition of Panx1 channels in tissues in future
studies. Thus, these results open up new avenues for the detailed analysis of
the subcellular localization of Panx1 and of its nearest neighbors such as
purinergic receptors in vivo. Pannexins are a family of integral membrane proteins with distinct
post-translational modifications, sub-cellular localization and tissue
distribution. Panx1 is the most studied and best-characterized isoform of this
gene family. The ubiquitous expression, as well as its function as a major ATP
release and nucleotide permeation channel, makes Panx1 a primary candidate for
participating in the pathophysiology of CNS disorders. While many investigations
revolve around Panx1 functions in health and disease, more recently, details
started emerging about mechanisms that control Panx1 channel activity. These
advancements in Panx1 biology have revealed that beyond its classical role as an
unopposed plasma membrane channel, it participates in alternative pathways
involving multiple intracellular compartments, protein complexes and a myriad of
extracellular participants. Here, we review recent progress in our understanding
of Panx1 at the center of these pathways, highlighting its modulation in a
context specific manner. This article is part of a Special Issue entitled: Gap
Junction Proteins edited by Jean Claude Herve. Pannexins (Panx1, 2, 3) are channel-forming glycoproteins expressed in mammalian
tissues. We previously reported that N-glycosylation acts as a regulator of the
localization and intermixing of Panx1 and Panx3, but its effects on Panx2 are
currently unknown. Panx1 and Panx2 intermixing can regulate channel properties,
and both pannexins have been implicated in neuronal cell death after ischemia.
Our objectives were to validate the predicted N-glycosylation site of Panx2 and
to study the effects of Panx2 glycosylation on localization and its capacity to
interact with Panx1. We used site-directed mutagenesis, enzymatic
de-glycosylation, cell-surface biotinylation, co-immunoprecipitation, and
confocal microscopy. Our results showed that N86 is the only N-glycosylation
site of Panx2. Panx2 and the N86Q mutant are predomitly localized to the
endoplasmic reticulum (ER) and cis-Golgi matrix with limited cell surface
localization was seen only in the presence of Panx1. The Panx2 N86Q mutant is
glycosylation-deficient and tends to aggregate in the ER reducing its cell
surface trafficking but it can still interact with Panx1. Our study indicates
that N-glycosylation may be important for folding and trafficking of Panx2. We
found that the un-glycosylated forms of Panx1 and 2 can readily interact,
regulating their localization and potentially their channel function in cells
where they are co-expressed. |
What is the mechanism of action of cariprazine? | Cariprazine is a dopamine D3/D2 partial agonist atypical antipsychotic with preferential binding to D3 receptors. Cariprazine shows also has affinity for 5-HT2B, and 5-HT1A receptors. It also shows moderate affinity toward σ1, 5-HT2A, and histamine H1 receptors. It is approved for the treatment of schizophrenia and manic or mixed episodes associated with bipolar I disorder | RATIONALE: Cariprazine (RGH-188) is a D₃-preferring dopamine D₃/D₂ receptor
partial agonist antipsychotic candidate for the treatment of schizophrenia and
bipolar mania. Substance abuse is a frequent comorbidity of both disorders and
is associated with serious health issues. Based on preclinical efficacy,
dopamine D₂ and D₃ receptor partial agonists and antagonists are assumed to have
relapse-preventing potential in human cocaine addiction.
OBJECTIVES: We investigated the anti-abuse potential of cariprazine in cocaine
self-administration paradigms. Aripiprazole and bifeprunox were used as
comparators because of their pharmacological similarity to cariprazine.
METHODS: The effects of compounds on cocaine's rewarding effect were
investigated in a continuous self-administration regimen. The relapse-preventing
potential of drugs was studied in rats with a history of cocaine
self-administration after a period of complete abstinence in a relapse to
cocaine-seeking paradigm.
RESULTS: Cariprazine, as well as aripiprazole and bifeprunox, were able to
reduce the rewarding effect of cocaine (minimum effective doses were 0.17, 1,
and 0.1 mg/kg, respectively) and attenuated relapse to cocaine seeking with half
maximal effective dose [ED₅₀] values of 0.2, 4.2, and 0.17 mg/kg, respectively.
CONCLUSIONS: These results may predict a relapse-preventing action for
cariprazine in humans in addition to its already established antipsychotic and
antimanic efficacy. The aim of this study was to evaluate whether chronic treatment with
cariprazine, a dopamine D2 and D3 receptor partial agonist with preferential
binding to D3 receptors, shows antidepressant-like effects in the chronic mild
stress (CMS)-induced anhedonia model. Male Wistar rats were subjected to the CMS
procedure for 7 weeks; nonstressed animals served as controls. For the last 5
weeks of the CMS procedure, rats were injected once daily with vehicle,
imipramine (10 mg/kg), aripiprazole (1 and 5 mg/kg), or cariprazine (0.01, 0.03,
0.065, 0.25, and 1.0 mg/kg). Activity in reversing CMS-induced decreases in
consumption of 1% solution of sucrose was measured. CMS significantly reduced
sucrose intake. Imipramine, and both doses of aripiprazole and cariprazine 0.03,
0.065, and 0.25 mg/kg significantly attenuated CMS-induced reductions in sucrose
intake; the lowest and highest cariprazine doses (0.01 and 1 mg/kg) did not have
this effect. Cariprazine showed greater potency (ED50=0.052) relative to
aripiprazole (ED50=4.4) in this model. Thus, in the rat CMS model, cariprazine
showed antidepressant-like action with greater potency than aripiprazole. These
results suggest that cariprazine may have clinical utility in the treatment of
depression and the negative symptoms of schizophrenia. Cariprazine is an antipsychotic medication and received approval by the U.S.
Food and Drug Administration for the treatment of schizophrenia in September
2015. Cariprazine is a dopamine D3 and D2 receptor partial agonist, with a
preference for the D3 receptor. Cariprazine is also a partial agonist at the
serotonin 5-HT1A receptor and acts as an antagonist at 5-HT2B and 5-HT2A
receptors. The recommended dose range of cariprazine for the treatment of
schizophrenia is 1.5-6 mg/d; the starting dose of 1.5 mg/d is potentially
therapeutic. Cariprazine is administered once daily and is primarily metabolized
in the liver through the CYP3A4 enzyme system and, to a lesser extent, by
CYP2D6. There are two active metabolites of note, desmethyl-cariprazine and
didesmethyl-cariprazine; the latter's half-life is substantially longer than
that for cariprazine and systemic exposure to didesmethyl-cariprazine is several
times higher than that for cariprazine. Three positive, 6-week, Phase 2/3,
randomized controlled trials in acute schizophrenia demonstrated superiority of
cariprazine over placebo. Pooled responder rates were 31% for cariprazine 1.5-6
mg/d vs. 21% for placebo, resulting in a number needed to treat (NNT) of 10. In
a 26-72 week, randomized withdrawal study, significantly fewer patients relapsed
in the cariprazine group compared with placebo (24.8% vs. 47.5%), resulting in
an NNT of 5. The most commonly encountered adverse events (incidence ≥5% and at
least twice the rate of placebo) are extrapyramidal symptoms (number needed to
harm [NNH] 15 for cariprazine 1.5-3 mg/d vs. placebo and NNH 10 for 4.5-6 mg/d
vs. placebo) and akathisia (NNH 20 for 1.5-3 mg/d vs. placebo and NNH 12 for
4.5-6 mg/d vs. placebo). Short-term weight gain appears small (approximately 8%
of patients receiving cariprazine 1.5-6 mg/d gained ≥7% body weight from
baseline, compared with 5% for those randomized to placebo, resulting in an NNH
of 34). Cariprazine is associated with no clinically meaningful alterations in
metabolic variables, prolactin, or the ECG QT interval. Cariprazine is also
approved for the acute treatment of manic or mixed episodes associated with
bipolar I disorder. Clinical trials are ongoing in patients with acute bipolar I
depression and as adjunctive treatment to antidepressant therapy in patients
with major depressive disorder. OBJECTIVE: Cariprazine, a dopamine D3/D2 partial agonist atypical antipsychotic
with preferential binding to D3 receptors, is approved for the treatment of
schizophrenia and manic or mixed episodes associated with bipolar I disorder.
The efficacy and safety of cariprazine was established in three randomized,
double-blind, placebo-controlled, 6-week trials in patients with acute
exacerbation of schizophrenia. This 53-week study evaluated the long-term safety
and tolerability of cariprazine in patients with schizophrenia.
METHODS: This was a multicenter, open-label, flexible-dose study of cariprazine
3-9 mg/d in adults with schizophrenia. Participants included new patients and
patients who had completed one of two phase III lead-in studies (NCT01104766,
NCT01104779). Eligible patients entered a no-drug screening period of up to 1
week followed by 48 weeks of flexibly dosed, open-label cariprazine treatment
(3-9 mg/d) and 4 weeks of safety follow-up.
RESULTS: A total of 586 patients received open-label cariprazine treatment, ~39%
of whom completed the study. No unexpected safety issues or deaths were
reported. The most common (≥10%) adverse events (AEs) observed were akathisia
(16%), headache (13%), insomnia (13%), and weight gain (10%). Serious AEs
occurred in 59 (10.1%) patients, and 73 (12.5%) patients discontinued the study
due to AEs during open-label treatment. Mean changes in metabolic, hepatic, and
cardiovascular parameters were not considered clinically relevant. Mean body
weight increased by 1.5 kg during the study, prolactin levels decreased
slightly, and measures of efficacy remained stable.
CONCLUSIONS: Long-term cariprazine treatment at doses up to 9 mg/d appeared to
be generally safe and well tolerated in patients with schizophrenia. BACKGROUND: Cariprazine, a D3-preferring dopamine D2/D3 receptor partial
agonist, is a new antipsychotic drug recently approved in the United States for
the treatment of schizophrenia and bipolar mania. We recently demonstrated that
cariprazine also has significant antianhedonic-like effects in rats subjected to
chronic stress; however, the exact mechanism of action for cariprazine's
antidepressant-like properties is not known. Thus, in this study we examined
whether the effects of cariprazine are mediated by dopamine D3 receptors.
METHODS: Wild-type and D3-knockout mice were exposed to chronic unpredictable
stress for up to 26 days, treated daily with vehicle, imipramine (20 mg/kg),
aripiprazole (1 and 5 mg/kg), or cariprazine (0.03, 0.1, 0.2, and 0.4 mg/kg),
and tested in behavioral assays measuring anhedonia and anxiety-like behaviors.
RESULTS: Results showed that cariprazine significantly attenuated chronic
unpredictable stress-induced anhedonic-like behavior in wild-type mice,
demonstrating potent antidepressant-like effects comparable with aripiprazole
and the tricyclic antidepressant imipramine. This antianhedonic-like effect of
cariprazine was not observed in D3-knockout mice, suggesting that the
cariprazine antidepressant-like activity is mediated by dopamine D3 receptors.
Moreover, cariprazine significantly reduced drinking latency in the
novelty-induced hypophagia test in wild-type mice, further confirming its
antianhedonic-like effect and showing that it also has anxiolytic-like activity.
CONCLUSIONS: In combination with previous studies, these results suggest that
cariprazine has a unique pharmacological profile and distinct dopamine D3
receptor-dependent mechanism of action that may be beneficial in the treatment
of schizophrenia, bipolar disorder, and major depressive disorder. In spite of tremendous development in central nervous system research, current
treatment is suboptimal, especially in severe mental disorders. In medicine,
there are two main methods of improving the health care provided: seeking new
treatment procedures and perfecting (optimizing) the existing ones. Optimization
of treatment includes not only practical tools such as therapeutic drug
monitoring but also implementation of general trends in the clinical practice.
New pharmacological options include new more sophisticated forms of
monoaminergic drugs, old drugs rediscovered on the base of a better
understanding of pathophysiology of mental illnesses, and drugs aimed at new
treatment targets. In depression, treatment resistance to antidepressive
pharmacotherapy represents one of the most important clinical challenges.
Switching to monotherapy with new multimodal/multifunctional antidepressants and
augmentation with new atypical antipsychotics (aripiprazole and brexpiprazole)
may be promising options. Further, current evidence supports utility and safety
of adjunctive treatment of nutraceuticals. Novel approaches being studied
include ketamine and opioids. Recent advances in technology and emerging
knowledge about dysfunctional brain circuits and neuroplasticity have led to the
development of different new neuromodulation techniques usually used as add-on
therapy. Antipsychotics are still the cornerstone of the current treatment of
schizophrenia. Two new partial dopamine agonists, brexpiprazole and cariprazine,
are now available in addition to aripiprazole. Although the mechanisms of action
are similar, the two agents differ in terms of their pharmacodynamic profiles.
Further, two new formulations of long-acting injections of second-generation
antipsychotics (aripiprazole lauroxil and 3-month paliperidone palmitate) were
introduced into clinical practice. New treatment options not yet available
include cannabidiol, glutamate modulators, and nicotine receptors agonists. Cariprazine, an orally active and potent dopamine D3-preferring D3/D2 receptor
partial agonist, is approved to treat adults with schizophrenia (in the United
States and Europe) and manic or mixed episodes associated with bipolar I
disorder (in the United States). Cariprazine also displays partial agonism at
serotonin [5-hydroxytryptamine (5-HT)] 5-HT1A receptors and antagonism at 5-HT2A
and 5-HT2B receptors in vitro. The study objective was to determine whether
cariprazine leads to functional alterations of monoamine systems in vivo via
electrophysiological recordings from anesthetized rats. Dorsal raphe nucleus
(DRN), locus coeruleus (LC), and hippocampus pyramidal neurons were recorded,
and cariprazine was administered systemically or locally through iontophoresis.
In the DRN, cariprazine completely inhibited the firing activity of 5-HT
neurons, which was fully reversed by the 5-HT1A receptor antagonist, WAY100635.
In the LC, cariprazine reversed the inhibitory effect of the preferential 5-HT2A
receptor agonist, 2,5-dimethoxy-4-iodoamphetamine, on norepinephrine (NE)
neurons (ED50 = 66 µg/kg) but did not block the inhibitory effect of the α
2-adrenergic receptor agonist, clonidine. Cariprazine, iontophorized into the
hippocampus, diminished pyramidal neuronal firing through activation of 5-HT1A
receptors, while its concomitant administration did not dampen the suppressant
effect of 5-HT. These results indicate that, in vivo, cariprazine acted as a
5-HT1A autoreceptor agonist in the DRN, a 5-HT2A receptor antagonist in
modulating the firing activity of LC NE neurons, and a full agonist at 5-HT1A
receptors mediating the electrophysiological effect of 5-HT on pyramidal
neurons. The modulatory actions of cariprazine on these monoaminergic systems
may contribute to its therapeutic effectiveness in patients with depressive
episodes. |
Which tool is used to visualise the junction sites of chloroplast genomes? | IRscope is an online program to visualize the junction sites of chloroplast genomes. It allows the users to depict the genetic architecture of up to ten chloroplast genomes in the vicinity of the sites connecting the inverted repeats to the short and long single copy regions. The software and its dependent libraries are fully coded in R and the reflected plot is scaled up to realistic size of nucleotide base pairs in the vicinity of the junction sites. The input of the program is an annotation GenBank (.gb) file, the accession or GI number of the sequence or a DOGMA output file. | MOTIVATION: Genome plotting is performed using a wide range of visualizations
tools each with emphasis on a different informative dimension of the genome.
These tools can provide a deeper insight into the genomic structure of the
organism.
RESULTS: Here, we announce a new visualization tool that is specifically
designed for chloroplast genomes. It allows the users to depict the genetic
architecture of up to ten chloroplast genomes in the vicinity of the sites
connecting the inverted repeats to the short and long single copy regions. The
software and its dependent libraries are fully coded in R and the reflected plot
is scaled up to realistic size of nucleotide base pairs in the vicinity of the
junction sites. We introduce a website for easier use of the program and R
source code of the software to be used in case of preferences to be changed and
integrated into personal pipelines. The input of the program is an annotation
GenBank (.gb) file, the accession or GI number of the sequence or a DOGMA output
file. The software was tested using over a 100 embryophyte chloroplast genomes
and in all cases a reliable output was obtained.
AVAILABILITY AND IMPLEMENTATION: Source codes and the online suit available at
https://irscope.shinyapps.io/irapp/ or https://github.com/Limpfrog/irscope. |
Which curated databases exist for spider-venom toxins? | ArachnoServer and its updated version ArachnoServer 2.0 are manually curated databases providing information on the sequence, structure and biological activity of protein toxins from spider venoms. | BACKGROUND: Venomous animals incapacitate their prey using complex venoms that
can contain hundreds of unique protein toxins. The realisation that many of
these toxins may have pharmaceutical and insecticidal potential due to their
remarkable potency and selectivity against target receptors has led to an
explosion in the number of new toxins being discovered and characterised. From
an evolutionary perspective, spiders are the most successful venomous animals
and they maintain by far the largest pool of toxic peptides. However, at
present, there are no databases dedicated to spider toxins and hence it is
difficult to realise their full potential as drugs, insecticides, and
pharmacological probes.
DESCRIPTION: We have developed ArachnoServer, a manually curated database that
provides detailed information about proteinaceous toxins from spiders. Key
features of ArachnoServer include a new molecular target ontology designed
especially for venom toxins, the most up-to-date taxonomic information
available, and a powerful advanced search interface. Toxin information can be
browsed through dynamic trees, and each toxin has a dedicated page summarising
all available information about its sequence, structure, and biological
activity. ArachnoServer currently manages 567 protein sequences, 334 nucleic
acid sequences, and 51 protein structures.
CONCLUSION: ArachnoServer provides a single source of high-quality information
about proteinaceous spider toxins that will be an invaluable resource for
pharmacologists, neuroscientists, toxinologists, medicinal chemists, ion channel
scientists, clinicians, and structural biologists. ArachnoServer is available
online at http://www.arachnoserver.org. ArachnoServer (www.arachnoserver.org) is a manually curated database providing
information on the sequence, structure and biological activity of protein toxins
from spider venoms. These proteins are of interest to a wide range of biologists
due to their diverse applications in medicine, neuroscience, pharmacology, drug
discovery and agriculture. ArachnoServer currently manages 1078 protein
sequences, 759 nucleic acid sequences and 56 protein structures. Key features of
ArachnoServer include a molecular target ontology designed specifically for
venom toxins, current and historic taxonomic information and a powerful advanced
search interface. The following significant improvements have been implemented
in version 2.0: (i) the average and monoisotopic molecular masses of both the
reduced and oxidized form of each mature toxin are provided; (ii) the advanced
search feature now enables searches on the basis of toxin mass, external
database accession numbers and publication date in ArachnoServer; (iii) toxins
can now be browsed on the basis of their phyletic specificity; (iv) rapid BLAST
searches based on the mature toxin sequence can be performed directly from the
toxin card; (v) private silos can be requested from research groups engaged in
venoms-based research, enabling them to easily manage and securely store data
during the process of toxin discovery; and (vi) a detailed user manual is now
available. |
What is the difference between CRISPR-Cas12a and CRISPR-Cpf1? | CRISPR-Cas12a and CRISPR-Cpf1 refer to the same thing. | |
Please list 2 antitoxin antibodies approved by the FDA for reducing the recurrence of Clostridium difficile infection | The antitoxin antibodies actoxumab and bezlotoxumab bind to and neutralize TcdA and TcdB, respectively. Bezlotoxumab was recently approved by the FDA for reducing the recurrence of CDI. | Clostridium difficile infection (CDI) represents the most prevalent cause of
antibiotic-associated gastrointestinal infections in health care facilities in
the developed world. Disease symptoms are caused by the two homologous
exotoxins, TcdA and TcdB. Standard therapy for CDI involves administration of
antibiotics that are associated with a high rate of disease recurrence,
highlighting the need for novel treatment paradigms that target the toxins
rather than the organism itself. A combination of human monoclonal antibodies,
actoxumab and bezlotoxumab, directed against TcdA and TcdB, respectively, has
been shown to decrease the rate of recurrence in patients treated with
standard-of-care antibiotics. However, the exact mechanism of antibody-mediated
protection is poorly understood. In this study, we show that the antitoxin
antibodies are protective in multiple murine models of CDI, including systemic
and local (gut) toxin challenge models, as well as primary and recurrent models
of infection in mice. Systemically administered actoxumab-bezlotoxumab prevents
both the damage to the gut wall and the inflammatory response, which are
associated with C. difficile in these models, including in mice challenged with
a strain of the hypervirulent ribotype 027. Furthermore, mutant antibodies
(N297Q) that do not bind to Fcγ receptors provide a level of protection similar
to that of wild-type antibodies, demonstrating that the mechanism of protection
is through direct neutralization of the toxins and does not involve host
effector functions. These data provide a mechanistic basis for the prevention of
recurrent disease observed in CDI patients in clinical trials. The exotoxins toxin A (TcdA) and toxin B (TcdB) are produced by the bacterial
pathogen Clostridium difficile and are responsible for the pathology associated
with C. difficile infection (CDI). The antitoxin antibodies actoxumab and
bezlotoxumab bind to and neutralize TcdA and TcdB, respectively. Bezlotoxumab
was recently approved by the FDA for reducing the recurrence of CDI. We have
previously shown that a single molecule of bezlotoxumab binds to two distinct
epitopes within the TcdB combined repetitive oligopeptide (CROP) domain,
preventing toxin binding to host cells. In this study, we characterize the
binding of actoxumab to TcdA and examine its mechanism of toxin neutralization.
Using a combination of approaches including a number of biophysical techniques,
we show that there are two distinct actoxumab binding sites within the CROP
domain of TcdA centered on identical amino acid sequences at residues 2162-2189
and 2410-2437. Actoxumab binding caused the aggregation of TcdA especially at
higher antibody:toxin concentration ratios. Actoxumab prevented the association
of TcdA with target cells demonstrating that actoxumab neutralizes toxin
activity by inhibiting the first step of the intoxication cascade. This
mechanism of neutralization is similar to that observed with bezlotoxumab and
TcdB. Comparisons of the putative TcdA epitope sequences across several C.
difficile ribotypes and homologous repeat sequences within TcdA suggest a
structural basis for observed differences in actoxumab binding and/or
neutralization potency. These data provide a mechanistic basis for the
protective effects of the antibody in vitro and in vivo, including in various
preclinical models of CDI. OBJECTIVE: To review the pharmacology, pharmacokinetics, efficacy, safety, and
place in therapy of bezlotoxumab (BEZ), a novel monoclonal antibody against
Clostridium difficile toxin B.
DATA SOURCES: A PubMed search was conducted for data between 1946 and April 2017
using MeSH terms bezlotoxumab, MK-6072, or MDX-1388 alone and the terms
Clostridium difficile combined with monoclonal antibody or antitoxin.
STUDY SELECTION AND DATA EXTRACTION: The literature search was limited to
English-language studies that described clinical efficacy, safety, and
pharmacokinetics in humans and animals. Abstracts featuring prepublished data
were also evaluated for inclusion.
DATA SYNTHESIS: BEZ is indicated for adult patients receiving standard-of-care
(SoC) antibiotics for C difficile infection (CDI) to prevent future recurrence.
Two phase III trials-MODIFY I (n = 1452) and MODIFY II (n = 1203)-demonstrated a
40% relative reduction in recurrent CDI (rCDI) with BEZ compared with placebo
(16.5% vs 26.6%, P < 0.0001). The most common adverse drug events associated
with BEZ were mild to moderate infusion-related reactions (10.3%).
CONCLUSIONS: In patients treated with SoC antibiotics, BEZ is effective in
decreasing rCDI. BEZ has no apparent effect on treatment of an initial CDI
episode. In light of increasing rates of CDI, BEZ is a promising option for
preventing recurrent episodes. The greatest benefit has been demonstrated in
high-risk patients, though the targeted patient population is yet to be defined. Clostridium difficile infection (CDI) is the most common nosocomial infection in
the U.S. 25% of CDI patients go on to develop recurrent CDI (rCDI) following
current standard of care (SOC) therapy, leading to morbidity, mortality and
economic loss. The first passive immunotherapy drug targeting C.difficile toxin
B (bezlotoxumab) has been approved recently by the FDA and EMA for prevention of
rCDI. Areas covered: A body of key studies was selected and reviewed by the
authors. The unmet needs in CDI care were ascertained with emphasis in rCDI,
including the epidemiology, pathophysiology and current management. The current
knowledge about the immune response to C. difficile toxins and how this
knowledge led to the development and the clinical use of bezlotoxumab is
described. Current and potential future competitors to the drug were examined.
Expert commentary: A single 10 mg/kg intravenous infusion of bezlotoxumab has
been shown to decrease rCDI by ~40% (absolute reduction ~10%) in patients being
treated for primary CDI or rCDI with SOC antibiotics. Targeting C.difficile
toxins by passive immunotherapy is a novel mechanism for prevention of
C.difficile infection. Bezlotoxumab will be a valuable adjunctive therapy to
reduce the burden of CDI. During the past decade, the incidence and severity of Clostridium difficile
infection (CDI) have significantly increased, leading to a rise in
CDI-associated hospitalizations, health care costs, and mortality. Although
treatment options exist for CDI, recurrence is frequent following treatment.
Furthermore, patients with at least one CDI recurrence are at an increased risk
of developing additional recurrences. A novel approach to the prevention of
recurrent CDI is the use of monoclonal antibodies directed against the toxins
responsible for CDI as an adjunct to antibiotic treatment. Bezlotoxumab, a human
monoclonal antibody that binds and neutralizes C. difficile toxin B, is the
first therapeutic agent to receive United States Food and Drug Administration
approval for the prevention of CDI recurrence. Clinical studies have
demonstrated superior efficacy of bezlotoxumab in adults receiving antibiotic
therapy for CDI compared with antibiotic therapy alone for the prevention of CDI
recurrence. Bezlotoxumab was well tolerated in clinical trials, with the most
common adverse effects being nausea, vomiting, fatigue, pyrexia, headache, and
diarrhea. The demonstrated efficacy, safety, and characteristics of bezlotoxumab
present an advance in prevention of CDI recurrence. Bezlotoxumab (Zinplava™) is a fully human monoclonal antibody against
Clostridium difficile toxin B indicated for the prevention of C. difficile
infection (CDI) recurrence in patients with a high recurrence risk. It is the
first agent approved for recurrence prevention and is administered as a single
intravenous infusion in conjunction with standard-of-care (SoC) antibacterial
treatment for CDI. In well-designed, placebo-controlled, phase 3 trials (MODIFY
1 and 2), a single infusion of bezlotoxumab, given in combination with SoC
antibacterial therapy for CDI in adults, was effective in reducing CDI
recurrence in the 12 weeks post-treatment, with this benefit being seen mainly
in the patients at high recurrence risk. Bezlotoxumab did not impact the
efficacy of the antibacterials being used to treat the CDI and, consistent with
its benefits on CDI recurrence, appeared to reduce the need for subsequent
antibacterials, thus minimizing further gut microbiota disruption. Longer term,
there were no further CDI recurrences over 12 months' follow-up among patients
who had received bezlotoxumab in MODIFY 2 and entered an extension substudy.
Bezlotoxumab has low immunogenicity and is generally well tolerated, although
the potential for heart failure in some patients requires consideration;
cost-effectiveness data for bezlotoxumab are awaited with interest. Thus, a
single intravenous infusion of bezlotoxumab during SoC antibacterial treatment
for CDI is an emerging option for reducing CDI recurrence in adults at high risk
of recurrence. Bezlotoxumab (Zinplava) for Clostridium Difficile Infection: The First
Monoclonal Antibody Approved to Prevent the Recurrence of a Bacterial Infection. Clostridium difficile infection is a significant cause of infectious diarrhoea
and is associated with considerable morbidity and mortality.1,2 Management of
Clostridium difficile infection often requires treatment with antibiotics
(metronidazole, vancomycin or fidaxomicin) alongside supportive care to manage
hydration, electrolytes and nutrition. However, the risk of recurrence is
approximately 20%.2 Here, we review the evidence for bezlotoxumab (▼ Zinplava -
Merck Sharp & Dohme Limited), a monoclonal antibody licensed for the prevention
of recurrence of Clostridium difficile in adults who are at high risk of
recurrence. |
List the functions of the protein lactotransferrin. | Lactotransferrin has numerous biological roles, including the regulation of iron absorption and modulation of immune responses, and has anti-microbial, anti-viral, antioxidant, anti-cancer, and anti-inflammatory activities. | Gastric cancer (GC) is the second leading cause of cancer-associated mortality
worldwide. In advanced and metastatic GC, conventional chemotherapy results in
limited efficacy and the average survival rate is currently approximately 10
months. Dysregulated activation of numerous genes, including zinc finger,
DHHC-type containing 14; caspase-associated recruitment domain-containing
protein; and Ras association domain family member 10, have been implicated in
GC. The tumor suppressor function of lactotransferrin (LTF) has been reported in
a variety of tumors, including GC, nasopharyngeal carcinoma (NPC) and prostate
cancer. However, the mechanism of the tumor suppressor function of LTF in GC
remains unclear. In the present study, the expression levels of LTF in patient
GC tissue samples were investigated using reverse transcription-quantitative
polymerase chain reaction, and it was demonstrated that the LTF mRNA expression
level in GC tissue samples was reduced by ~20-fold compared with the adjacent
non-cancerous tissues (t=4.56, P<0.01). A similar trend in LTF protein
expression was observed by western blot analysis. Furthermore, the present study
demonstrated that the mitogen-activated protein kinase (MAPK) signaling pathway
intermediates p38, c-Jun N-terminal kinase (JNK) and c-Jun were highly expressed
in GC tissue samples, and indicated that LTF downregulation may be associated
with the dysregulation of the MAPK signaling pathway in GC tissues. In addition,
the present study indicated that LTF overexpression reduced the expression of
p38, JNK2 and c-Jun in the GC cell line, SGC7901. The present study demonstrates
that LTF expression is downregulated in GC tissues and that LTF may serve an
important role in the dysregulation of the MAPK signaling pathway. Lactoferrin (lactotransferrin; Lf) is an iron-binding glycoprotein and one of
the most important bioactivators in milk and other external secretions. It has
numerous biological roles, including the regulation of iron absorption and
modulation of immune responses, and has anti-microbial, anti-viral, antioxidant,
anti-cancer, and anti-inflammatory activities. Lf regulates the quantity of iron
absorbed in the intestine via its role in iron transport and can also chelate
iron, directly or indirectly. Notably, it has been used as an adjuvant therapy
for some intestinal diseases. It is now used in nutraceuticalsupplemented infant
formula and other food products. This article reviews the content, distribution,
physiologic functions and current applications of Lf, and aims to shed light on
future prospects for additional applications of Lf. |
Does Axitinib prolong survival of Pancreatic Cancer patients? | No. The addition of axitinib to gemcitabine does not improve overall survival in advanced pancreatic cancer. | BACKGROUND: Axitinib is a potent, selective inhibitor of vascular endothelial
growth factor (VEGF) receptors 1, 2, and 3. A randomised phase 2 trial of
gemcitabine with or without axitinib in advanced pancreatic cancer suggested
increased overall survival in axitinib-treated patients. On the basis of these
results, we aimed to assess the effect of treatment with gemcitabine plus
axitinib on overall survival in a phase 3 trial.
METHODS: In this double-blind, placebo-controlled, phase 3 study, eligible
patients had metastatic or locally advanced pancreatic adenocarcinoma, no
uncontrolled hypertension or venous thrombosis, and Eastern Cooperative Oncology
Group performance status 0 or 1. Patients, stratified by disease extent
(metastatic vs locally advanced), were randomly assigned (1:1) to receive
gemcitabine 1000 mg/m(2) intravenously on days 1, 8, and 15 every 28 days plus
either axitinib or placebo. Axitinib or placebo were administered orally with
food at a starting dose of 5 mg twice a day, which could be dose-titrated up to
10 mg twice daily if well tolerated. A centralised randomisation procedure was
used to assign patients to each treatment group, with randomised permuted blocks
within strata. Patients, investigators, and the trial sponsor were masked to
treatment assignments. The primary endpoint was overall survival. All efficacy
analyses were done in all patients assigned to treatment groups for whom data
were available; safety and treatment administration and compliance assessments
were based on treatment received. This study is registered at
ClinicalTrials.gov, number NCT00471146.
FINDINGS: Between July 27, 2007, and Oct 31, 2008, 632 patients were enrolled
and assigned to treatment groups (316 axitinib, 316 placebo). At an interim
analysis in January, 2009, the independent data monitoring committee concluded
that the futility boundary had been crossed. Median overall survival was 8·5
months (95% CI 6·9-9·5) for gemcitabine plus axitinib (n=314, data missing for
two patients) and 8·3 months (6·9-10·3) for gemcitabine plus placebo (n=316;
hazard ratio 1·014, 95% CI 0·786-1·309; one-sided p=0·5436). The most common
grade 3 or higher adverse events for gemcitabine plus axitinib and gemcitabine
plus placebo were hypertension (20 [7%] and 5 [2%] events, respectively),
abdominal pain (20 [7%] and 17 [6%]), fatigue (27 [9%] and 21 [7%]), and
anorexia (19 [6%] and 11 [4%]).
INTERPRETATION: The addition of axitinib to gemcitabine does not improve overall
survival in advanced pancreatic cancer. These results add to increasing evidence
that targeting of VEGF signalling is an ineffective strategy in this disease.
FUNDING: Pfizer. INTRODUCTION: Advanced understanding of the pathogenesis of renal cell carcinoma
(RCC) has led to development and approval of several molecularly targeted
therapies since 2005. Axitinib is a potent and selective inhibitor of vascular
endothelial growth factor receptors 1, 2 and 3. In the randomized Phase III AXIS
trial, axitinib significantly prolonged progression-free survival compared with
sorafenib, respectively (6.7 vs 4.7 months; p < 0.0001), and improved objective
response rate (19 vs 9%; p = 0.0001), resulting in its approval for advanced or
metastatic RCC after failure of one systemic therapy. However, overall survival
was similar with axitinib and sorafenib. Common adverse events associated with
axitinib include diarrhea, hypertension and fatigue.
AREAS COVERED: The properties, clinical efficacy, adverse events,
pharmacokinetics and pharmacodynamics of axitinib are summarized and its
position in the overall therapeutic landscape for metastatic RCC among several
targeted therapies is described.
EXPERT OPINION: Axitinib is generally well-tolerated and provides definitive
clinical benefits in patients with advanced or metastatic RCC as second-line
therapy. However, as with other tyrosine kinase inhibitors of the same class,
axitinib does not prolong overall survival; therefore, selection of second-line
tyrosine kinase inhibitor therapy, including axitinib, must be carefully
considered to maximize outcomes for each patient. OBJECTIVE: Axitinib is a potent and selective inhibitor of vascular endothelial
growth factor receptors 1-3. This analysis compared efficacy and safety of
axitinib plus gemcitabine in patients with advanced pancreatic cancer from
Japan, North America and the European Union, enrolled in a randomized Phase III
study.
METHODS: Patients (n = 632), stratified by disease extent, were randomly
assigned (1:1) to receive axitinib/gemcitabine or placebo/gemcitabine. Axitinib
was administered at a starting dose of 5 mg orally twice daily and gemcitabine
at 1000 mg/m(2) once weekly for 3 weeks in 4 week cycles. Primary endpoint was
overall survival.
RESULTS: Among Japanese patients, median overall survival was not estimable (95%
confidence interval, 7.4 months-not estimable) with axitinib/gemcitabine (n =
58) and 9.9 months (95% confidence interval, 7.4-10.5) with placebo/gemcitabine
(n = 56) (hazard ratio 1.093 [95% confidence interval, 0.525-2.274]). Median
survival follow-up (range) was 5.1 months (0.02-12.3) with axitinib/gemcitabine
vs. 5.4 months (1.8-10.5) with placebo/gemcitabine. Similarly, no difference was
detected in overall survival between axitinib/gemcitabine and
placebo/gemcitabine in patients from North America or the European Union. Common
adverse events with axitinib/gemcitabine in Japanese patients were fatigue,
anorexia, dysphonia, nausea and decreased platelet count. Axitinib safety
profile was generally similar in patients from the three regions, although there
were differences in incidence of some adverse events. An exploratory analysis
did not show any correlation between axitinib/gemcitabine-related hypertension
and overall survival.
CONCLUSIONS: Axitinib/gemcitabine, while tolerated, did not provide survival
benefit over gemcitabine alone in patients with advanced pancreatic cancer from
Japan or other regions. |
Which Python tool has been developed for network-based stratification of tumor mutations? | PyNBS is a modularized Python 2.7 implementation of the network-based stratification (NBS) algorithm for stratifying tumor somatic mutation profiles into molecularly and clinically relevant subtypes. | |
Through which protein interaction does MLP regulate F-actin dynamics? | The interaction of MLP with CFL2 has direct implications in actin cytoskeleton dynamics in regulating CFL2-dependent F-actin depolymerization, with maximal depolymerization enhancement at an MLP/CFL2 molecular ratio of 2:1. Deregulation of this interaction by intracellular pH variations, CFL2 phosphorylation, MLP or CFL2 gene mutations, or expression changes, as observed in a range of cardiac and skeletal myopathies, could impair F-actin depolymerization, leading to sarcomere dysfunction and disease. | The muscle LIM protein (MLP) and cofilin 2 (CFL2) are important regulators of
striated myocyte function. Mutations in the corresponding genes have been
directly associated with severe human cardiac and skeletal myopathies, and
aberrant expression patterns have often been observed in affected muscles.
Herein, we have investigated whether MLP and CFL2 are involved in common
molecular mechanisms, which would promote our understanding of disease
pathogenesis. We have shown for the first time, using a range of biochemical and
immunohistochemical methods, that MLP binds directly to CFL2 in human cardiac
and skeletal muscles. The interaction involves the inter-LIM domain, amino acids
94 to 105, of MLP and the amino-terminal domain, amino acids 1 to 105, of CFL2,
which includes part of the actin depolymerization domain. The MLP/CFL2 complex
is stronger in moderately acidic (pH 6.8) environments and upon CFL2
phosphorylation, while it is independent of Ca(2+) levels. This interaction has
direct implications in actin cytoskeleton dynamics in regulating CFL2-dependent
F-actin depolymerization, with maximal depolymerization enhancement at an
MLP/CFL2 molecular ratio of 2:1. Deregulation of this interaction by
intracellular pH variations, CFL2 phosphorylation, MLP or CFL2 gene mutations,
or expression changes, as observed in a range of cardiac and skeletal
myopathies, could impair F-actin depolymerization, leading to sarcomere
dysfunction and disease. |
Is there any association between suicide and autism in adolescents, yes or no? | Adults with autism spectrum disorder (ASD) are at increased risk of suicide compared to the general population. | The present exploratory study examined the level of peer victimization,
depressive symptomatology, anxiety symptomatology, and level of suicidal
ideation among adolescents and young adults diagnosed with Asperger's Syndrome
(AS). This cross-sectional study used a self-administrated mail questionnaire
and a Web-based questionnaire. The study included two samples. The first sample
used snowball sampling, beginning with parents of adolescents and young adults
diagnosed with AS who participated in a qualitative study conducted in 2002. The
second sample consisted of a volunteer sample of parents who accessed Web sites
for parents and individuals diagnosed with Autism Spectrum Disorder. A total
sample of 10 adolescents and young adults diagnosed with AS was obtained. The
high proportion of respondents with scores above the cutoff point on the overt
victimization and relational victimization scales suggests that these
adolescents and young adults experienced high levels of victimization. Of the
sample, 20 percent met criteria for a diagnosis of Major Depressive Disorder, 30
percent met criteria for Generalized Anxiety Disorder and 50 percent had
clinically significant level of suicidal ideation. The Autistic Spectrum Disorders (ASD) are characterized by an atypical
sociability, alterations in communication, restricted interests and
stereotypies, with adding affective and adaptative disabilities. The suicidal
behaviors are frequently observed in the adolescents and adults with an ASD
without intellectual deficience. However, the clinical research on the topic is
limited and the diagnosis not assessed in the emergency units. Among the
individual risk factors of the suicidal behavior in ASD patients, mood and
anxiety disorders are found as well as a familial affective disorder history.
The intimidation and the lack of socio-professional integration were also
reported as environnemental risk factors. Laters tudies taking into account the
cognitive characteristics would permit to investigate the suicidal phenomenology
in ASD patients. Suicide is a major problem in Western society. However we have very little
understanding of suicidal behaviour among individuals with autism spectrum
disorders. The purpose of this review is to synthesise primary research on
suicidal behaviour among adolescents and young adults with autism spectrum
disorders in order to estimate prevalence and to identify and critically
evaluate risk factors for suicidal behaviour in this population. Four primary
research studies were identified for this review following a comprehensive
literature search. The available research provides little empirical evidence for
the processes underlying suicidal behaviour in adolescents and young adults with
autism. Although the suicide risk of autism spectrum disorder (ASD) has been suggested
to be higher than previously recognized, there are few case reports focusing on
the process for preventing suicide reattempts. We reported that a 17-year-old
male who had attempted suicide by jumping was admitted to our emergency
department and hospitalized for lumbar spine fracture. In addition to the
diagnosis of adjustment disorder, he was diagnosed as ASD according to his life
history. This article presents the characteristics of the suicidal behaviors and
the process for preventing a suicide reattempt associated with an adolescent
with ASD who attempted suicide. INTRODUCTION: Most studies on suicide exclude subjects with autism spectrum
disorders, yet there is a risk group. The purpose of this article is to present
the data in the literature regarding the clinical and epidemiological
characteristics of suicidality in subjects with autism spectrum disorders and to
identify the factors that promote the transition to action.
METHODS: This review was carried out using the data set collected in Medline
PubMed, items with "autism spectrum disorder", "pervasive developmental
disorder", "Asperger's syndrome", "suicide", "suicide attempt", and "suicide
behavior".
RESULTS: In all subjects from our research on PubMed, 21.3% of subjects with
autism spectrum disorder reported suicidal ideation, have attempted suicide or
died by suicide (115 out of 539 subjects) and 7.7% of subjects supported for
suicidal thoughts or attempted suicide exhibited an autism spectrum disorder (62
out of 806 subjects), all ages combined. Suicidal ideation and morbid
preoccupation are particularly common in adolescents and young adults. Suicide
attempts are accompanied by a willingness for death and can lead to suicide.
They are more common in high-functioning autism and Asperger subjects. The
methods used are often violent and potentially lethal or fatal in two cases
published. Suicide risk depends on many factors that highlight the vulnerability
of these subjects, following autistic and developmental symptoms. Vulnerability
complicating the diagnosis of comorbid depressive and anxiety disorders are
major factors associated with suicidality. Vulnerability but also directly
related to suicidality, since the origin of physical and sexual abuse and
victimization by peers assigning them the role of "scapegoat" are both
responsible for acting out.
CONCLUSION: Given the diversity of factors involved in the risk of suicide in
this population, this does not validate "a" program of intervention, but the
intervention of "customized programs". Their implementation should be as early
as possible in order to treat while the brain has the greatest plasticity. The
aim is to provide the necessary access to the greatest possible autonomy. Hence,
including working communication skills and interaction, these subject will have
independent means of protection, an essential complement to measures to protect
vulnerable subjects; the vulnerability of direct and indirect suicidality.
Comorbid diagnoses must take into account the specificities of these patients,
their difficulties in communicating their mental state, and adapted and
innovative therapeutic strategies must be offered and validated. OBJECTIVES: Considering that suicide is one of the most common reasons of
adolescent death worldwide, there is a lack of clinical awareness on suicidal
behaviors of children and adolescents with autism spectrum disorder (ASD). The
present study aims to assess the rate of suicidality (suicidal ideation,
behaviors and attempts) and associated risk factors for suicidality in high
functioning ASD.
METHODS: Medical records of 55 adolescents (six girls, 49 boys), aged between
7-20 years, with diagnosis of ASD were reviewed. The participants were all able
to speak fluently and had no significant limitations in intellectual
functioning. Clinical assessment of participants was carried out on the basis of
Diagnostic and Statistical Manual of Mental Disorders 4th Edition, Text Revision
criteria and Schedule for Affective Disorders and Schizophrenia for School-Age
Children-Present and Lifetime Version. Eskin's Suicide Screening Questionnaire
and sociodemographic data form including detailed history of suicidal behaviors
were used. The study group was also divided into suicidal and non-suicidal
groups for the purpose of comparing the results.
RESULTS: The rate of suicidal behaviors was 29% and suicide attempt was 12.7%.
Types of suicidality were behaviors (43.7%), thoughts (37.5%), and verbal
declarations (18.7%). A number of bizarre acts were recorded. Rates of comorbid
psychiatric disorders such as mood disorders, anxiety disorders and disruptive
behaviors were 23.6%, 43.6% and 65.4% respectively. Groups with the psychotic
features, positive family history for suicidal behaviors and completed suicide
showed more suicidality than the non-suicidal group.
CONCLUSION: Consistent with the previous findings, rate of suicidality is higher
in individuals with ASD. The type of suicidal behaviors showed some differences
compared to typically developing individuals. The presence of psychotic features
and positive family history for suicidality may be risk factors for suicidality
in children and adolescents with ASD. To prevent suicide and implement
protective health care systems, identifying the population at risk is crucial. BACKGROUND: Previous studies reported a high prevalence of depression among
patients with autism spectrum disorder (ASD) and suggested a relationship
between ASD and suicidality. However, whether ASD independently increases the
risk of attempted suicide regardless of depression has not been determined.
METHODS: Using the Taiwan National Health Insurance Research Database, 5,618
adolescents aged 12-17 years and young adults aged 18-29 years with ASD
(ICD-9-CM code: 299) and 22,472 age- and sex-matched controls were enrolled
between 2001 and 2009 and followed to the end of 2011. Any suicide attempt was
identified during the follow-up period.
RESULTS: Patients with ASD had a higher incidence of suicide attempts (3.9% vs
0.7%, P < .001) than did those without ASD. Both adolescents (HR = 5.79; 95% CI,
3.98-8.41) and young adults (HR = 5.38; 95% CI, 3.58-8.06) with ASD were more
likely to attempt suicide in later life after adjusting for demographic data and
psychiatric comorbidities. Sensitivity analyses after excluding the first year
(HR = 4.52; 95% CI, 3.39-6.03) or first 3 years (HR = 3.36; 95% CI, 2.40-4.70)
of observation showed consistent findings.
CONCLUSIONS: Patients with ASD had an increased risk of suicide attempts
compared with those without ASD. ASD was an independent risk factor of attempted
suicide. Further studies are needed to clarify the underlying pathophysiology
between ASD and suicidality and to elucidate whether prompt intervention for ASD
may reduce this risk. Until recently, suicidality in autism spectrum disorder (ASD) was rarely
discussed. A cluster of recent articles, including an article by Culpin et al.1
in this issue, has highlighted not only that suicidal thoughts and suicide
attempts can occur in adolescents and young adults with ASD, but also that
suicidality is likely more common in ASD than in the general population.
Retrospectively, the lack of focus on suicidality in ASD seems surprising when
self-injurious behavior has long been a focus of attention in ASD.2 The emerging
studies indicate that the increased risk of self-injurious behavior in younger
and less cognitively able children with ASD3,4 is matched by an increased risk
of suicidality in those at a more advanced developmental level. |
Is lactotransferrin a tumour suppressor? | Lactotransferrin (LTF) has been confirmed to act as a tumor suppressor in multiple cancers. | Lactotransferrin (LTF) has been shown to regulate tumorogenesis. However, little
is known about the role of LTF in regulating the development of human
nasopharyngeal carcinoma (NPC). The aim of our study was to investigate whether
LTF could regulate the development of NPC by characterizing the pattern of LTF
expression in human NPC tissues using cDNA and tissue microarrays. Loss of LTF
expression was observed in a significantly higher frequency of NPC tissues
compared to that in nontumor nasopharyngeal epithelial tissues. While 61.25% of
NPC tissues at the T1/T2 stage were positive for LTF expression, only 40.82% of
NPC at the T3/T4 stage were stained by anti-LTF. Similarly, 41.58% of NPC with
local lymph node metastasis displayed LTF expression, a value significantly
lower than the 46.36% in primary tumors (p < 0.05). These findings suggest that
LTF may negatively regulate the development and metastasis of NPC in vivo.
Furthermore, overexpression of or treatment with LTF inhibited the proliferation
of NPC cells and promoted cell cycle arrest at the G(0)/G(1) phase in vitro.
While LTF treatment downregulated expression of cyclin D1 and phosphorylation of
retinoblastoma protein (Rb), expression of p21 and p27 in 5-8F NPC cells was
enhanced. Moreover, LTF treatment modulated the mitogen-activated protein kinase
(MAPK) pathway, but did not affect p53 and STAT3 expression in 5-8F NPC cells.
Thus LTF is likely to be a candidate tumor suppressor and downregulates the
development of NPC by inhibiting NPC proliferation through induction of cell
cycle arrest and modulation of the MAPK signaling pathway. Therefore, our
findings provide new insights in understanding the mechanism(s) underlying the
action of LTF in regulating the development of human NPC. LTF (lactotransferrin, also known as lactoferrin) is a key component of innate
immune defense. It has recently been found to have anti-tumor and
anti-metastatic activity in different cancers. We previously reported LTF to be
the most significantly downregulated gene in nasopharyngeal carcinoma (NPC)
specimens relative to normal nasopharyngeal epithelial tissues, and it was also
negatively associated with the progression and metastasis of NPC. However, the
mechanism underlying this remains unclear. In the current study, we revealed
that LTF can suppress 3-phosphoinositide-dependent protein kinase 1 expression
via the mitogen-activated protein kinase/c-Jun pathway and thus repress AKT
signaling. We also showed that LTF interacts with keratin 18 (K18) and so blocks
the formation of the K18-14-3-3 complex, leading to downregulation of
K18-mediated AKT activation. Thus, LTF suppresses AKT signaling by two separate
mechanisms, leading to inhibition of NPC tumorigenesis. This is the first report
on the tumor suppressive effects of LTF through repression of AKT signaling in
NPC. It suggests that both LTF and AKT signaling merit further study in the
field of NPC research. LTF (lactotransferrin, or lactoferrin) plays important role in innate immunity,
and its anti-tumor function has also been reported in multiple cancers. We
previously reported that LTF is significantly down-regulated in nasopharyngeal
carcinoma (NPC) and acts as a tumor suppressor by suppressing AKT signaling.
However, the exact mechanism of the down-regulation of LTF in NPC has not been
revealed. In the current study, we screened and identified LTF is a bona fide
target of miR-214 in NPC cells. miR-214 mimics significantly suppressed LTF mRNA
and protein expression levels in NPC cells. miR-214 not only can promote NPC
cell proliferation and invasion abilities in vitro, but also can accelerate
tumor formation and lung metastasis in a mouse xenograft model. The pro-tumor
function of miR-214 was depended on LTF suppression since LTF re-expression can
reverse it. miR-214 can also activate AKT signaling by suppressing LTF
expression. Furthermore, miR-214 expression level was up-regulated in NPC
especially in metastasis-prone NPC tumor tissues compared with normal
nasopharyngeal epithelial tissues, while the LTF expression level was negatively
correlated with miR-214, suggesting that miR-214 targeting is partly responsible
for LTF down-regulation in NPC specimens. BACKGROUND: Lactotransferrin (LTF) has been confirmed to act as a tumor
suppressor in multiple cancers; however, its roles in oral squamous cell
carcinoma (OSCC), one of maligt head and neck carcinomas, has not been
explored.
METHODS: Here, the expression of LTF in OSCC tissues and TCA8113 cells was
detected with RT-PCR, qPCR, and IHC. And the correlation between LTF expression
and OSCC metastasis was assessed. MS-PCR was performed to reveal the methylation
status in promoter regions of LTF both in OSCC tissue samples and cells. The
influences of 5-Aza-Cdc treatment to the methylation status and expression
levels of LTF were also analyzed. At last, the functions of LTF in OSCC
progression were demonstrated by MTT analysis, clone formation assay, and cell
cycle analysis in TCA8113 cells with forced ectopic expression of LTF.
RESULTS: LTF showed a low or null expression pattern in OSCC tissues and cells,
at least partially, due to the hypermethylated status in promoter regions for
5-Aza-Cdc, a methyltransferase inhibitor, could restore the expression of LTF in
TCA8113 cells. And the expression level of LTF exhibited a negative correlation
with OSCC metastasis.
CONCLUSIONS: Re-expression of LTF inhibited the growth, proliferation, as well
as cell cycle progression of TCA8113 cells. In conclusion, hypermethylation
contributes much to LTF inactivation in OSCC. And LTF can partially reverse the
maligt phenotypes of OSCC cells and may be served as a potential target for
diagnosis and therapy of OSCC in future. Gastric cancer (GC) is the second leading cause of cancer-associated mortality
worldwide. In advanced and metastatic GC, conventional chemotherapy results in
limited efficacy and the average survival rate is currently approximately 10
months. Dysregulated activation of numerous genes, including zinc finger,
DHHC-type containing 14; caspase-associated recruitment domain-containing
protein; and Ras association domain family member 10, have been implicated in
GC. The tumor suppressor function of lactotransferrin (LTF) has been reported in
a variety of tumors, including GC, nasopharyngeal carcinoma (NPC) and prostate
cancer. However, the mechanism of the tumor suppressor function of LTF in GC
remains unclear. In the present study, the expression levels of LTF in patient
GC tissue samples were investigated using reverse transcription-quantitative
polymerase chain reaction, and it was demonstrated that the LTF mRNA expression
level in GC tissue samples was reduced by ~20-fold compared with the adjacent
non-cancerous tissues (t=4.56, P<0.01). A similar trend in LTF protein
expression was observed by western blot analysis. Furthermore, the present study
demonstrated that the mitogen-activated protein kinase (MAPK) signaling pathway
intermediates p38, c-Jun N-terminal kinase (JNK) and c-Jun were highly expressed
in GC tissue samples, and indicated that LTF downregulation may be associated
with the dysregulation of the MAPK signaling pathway in GC tissues. In addition,
the present study indicated that LTF overexpression reduced the expression of
p38, JNK2 and c-Jun in the GC cell line, SGC7901. The present study demonstrates
that LTF expression is downregulated in GC tissues and that LTF may serve an
important role in the dysregulation of the MAPK signaling pathway. |
What is CVT-301? | CVT-301 is inhaled levodopa (LD) formulation for development as a self-administered treatment for relief of OFF periods in Parkinson's disease. CVT-301 provided rapid improvement of motor function, and daily OFF time was significantly reduced at the higher dose. | BACKGROUND: Although levodopa is the most effective oral PD therapy, many
patients experience motor fluctuations, including sudden loss of dose effect and
delayed benefit. CVT-301 is a levodopa inhalation powder with the potential for
rapid onset of action. The objective of this study was to evaluate CVT-301
self-administered by PD patients to relieve OFF episodes.
METHODS: PD patients with ≥2 hours per day of OFF time despite oral levodopa ≥4
times per day were randomized to CVT-301 or placebo for 4 weeks, to be used up
to 3 times per day for OFF episodes. After 2 weeks, the study-drug dose was
escalated from 35 to 50 mg. The primary end point was mean change in UPDRS Part
III score from a predose OFF state to the average of postdose scores obtained at
10, 20, 30, and 60 minutes, as assessed in-clinic at the end of week 4. Home
diaries were recorded.
RESULTS: Eighty-six patients used the study drug at an average frequency of 2.1
times per day for CVT-301 and for placebo. At 4 weeks, least-squares mean change
in UPDRS Part III score favored CVT-301 by 7.0 points (P < 0.001). A treatment
effect was evident at 10 minutes. At 4 weeks, least-squares mean OFF-time change
from baseline favored CVT-301 by 0.9 hours per day (P = 0.045). The most
frequently reported adverse events in the CVT-301 group were dizziness, cough,
and nausea, each in 7% (3 of 43 patients).
CONCLUSIONS: CVT-301 self-administered during OFF episodes provided rapid
improvement of motor function, and daily OFF time was significantly reduced at
the higher dose. CVT-301 was generally safe and well-tolerated. © 2016 The
Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of
International Parkinson and Movement Disorder Society. BACKGROUND: Spirometry patterns suggesting restrictive and obstructive pulmonary
dysfunction have been reported in Parkinson's disease (PD). However, the
patterns' precise relation to PD pathophysiology remains unclear. Purpose/Aim.
To assess ON- versus OFF-state pulmonary function, the quality of its
spirometric evaluation, and the quality of longitudinal spirometric findings in
a large sample of PD patients with motor fluctuations.
METHODS: During a placebo-controlled trial of an inhaled levodopa formulation,
CVT-301, in PD patients with ≥2 h/d of OFF time, spirometry was performed by
American Thoracic Society (ATS) guidelines at screening and throughout the
4-week treatment period.
RESULTS: Among 86 patients, mean motor impairment during an OFF state at
screening was moderately severe. However, mean spirometry results at screening
were within normal ranges, and in a mixed model for repeated measures (MMRM),
the results at screening were not dependent on motor state (ON vs. OFF). In the
placebo group (n = 43), 76% of ON-state and 81% of OFF-state examinations
throughout the study met ATS quality metrics, and in an MMRM analysis, mean
findings at these patients' arrivals for treatment-period visits showed no
significant 4-week change. Across all 86 patients, flow-volume curves prior to
any study-drug administration showed only a 3% incidence of "sawtooth"
morphology.
CONCLUSIONS: In PD patients with motor fluctuations, longitudinal spirometry of
acceptable quality was generally obtained. Although mean findings were normal,
about a quarter of spirograms did not meet ATS quality criteria. Spirogram
morphology may be less indicative of various forms of respiratory dysfunction
than has previously been reported in PD. Inhaled drugs offer advantages, such as rapid onset of action, but require
formulations and delivery systems that reproducibly and conveniently administer
the drug. CVT-301 is a powder formulation of levodopa delivered by a
breath-actuated inhaler that has been developed for treating OFF episodes (motor
fluctuations between doses of standard oral levodopa) in patients with
Parkinson's disease (PD). We present preclinical, phase 1, and phase 2 results
for CVT-301. In dogs insufflated with a levodopa powder, plasma levodopa peaked
in all animals 2.5 min after administration; in contrast, in dogs dosed orally
with levodopa plus carbidopa, plasma levodopa was not detected until 30 min
after administration. In 18 healthy persons, comparisons between inhaled CVT-301
and oral carbidopa/levodopa showed analogous differences in pharmacokinetics.
Among 24 PD patients inhaling CVT-301 as a single 50-mg dose during an OFF
episode, 77% showed an increase in plasma levodopa (>400 ng/ml) within 10 min
versus 27% for oral dosing with carbidopa/levodopa at a 25-mg/100-mg dose.
Improvements in timed finger tapping and overall motor function (Part III of the
Unified Parkinson's Disease Rating Scale) were seen 5 and 15 min after
administration, the earliest assessment time points. For average and best
change, the improvements were statistically significant compared to placebo. The
most common adverse event was cough; all cough events were mild to moderate,
occurred at the time of inhalation, resolved rapidly, and became less frequent
after initial dosing. These results support further development of CVT-301 for
better management of PD. Levodopa remains the most effective treatment for Parkinson's disease and is
considered the gold standard therapy. However, disease progression and changes
in the gastrointestinal tract result in a declining window of treatment response
in a majority of patients. Efforts have been made recently to improve levodopa
bioavailability either by developing more effective oral formulations or by
innovating routes of administration (intestinal infusion, transcutaneous or
inhaled levodopa). IPX066 is a novel levodopa-carbidopa (LD/CD) oral formulation
combining immediate-release (IR) and extended-release (ER) LD/CD recently
approved in the USA and the EU. Levodopa-carbidopa intestinal gel (LCIG) is an
approved therapy consisting of a suspension of levodopa and carbidopa infused
directly into the proximal jejunum via a percutaneous endoscopic
gastrojejunostomy (PEG-J) tube through a portable infusion pump. Ongoing studies
are evaluating the 'accordion pill' (AP09004), an ER LD/CD formulation with
gastroretentive properties. ND0612 is a proprietary liquid formulation of LD/CD
that enables subcutaneous administration via a small patch-pump device, and
CVT-301 is a levodopa inhalation powder with rapid onset of action; both are
currently in active studies. Other novel formulations have been discontinued,
including DM-1992, which is a bilayer formulation containing an IR LD/CD layer
and an ER LD/CD layer with gastroretentive properties, and XP21279, a novel oral
levodopa prodrug that is absorbed from the small and large intestine by
high-capacity nutrient transporters expressed throughout the gastrointestinal
system. ODM-101 is a new oral formulation of levodopa/carbidopa/entacapone that
contains a higher amount of carbidopa (65 or 105 mg), but no active studies are
underway. The current review aims to summarize the pharmacokinetic aspects,
clinical efficacy, and potential adverse events of novel levodopa formulations
currently available or under development. BACKGROUND: Ever since the pioneering reports in the 60s,
L-3,4-Dioxyphenylalanine (levodopa) has represented the gold standard for the
treatment of Parkinson's Disease (PD). However, long-term levodopa (LD)
treatment is frequently associated with fluctuations in motor response with
serious impact on patient quality of life. The pharmacokinetic and
pharmacodynamic properties of LD are pivotal to such motor fluctuations:
discontinuous drug delivery, short half-life, poor bioavailability, and narrow
therapeutic window are all crucial for such fluctuations. During the last 60
years, several attempts have been made to improve LD treatment and avoid
long-term complications.
METHODS: Research and trials to improve the LD pharmacokinetic since 1960s are
reviewed, summarizing the progressive improvements of LD treatment.
RESULTS: Inhibitors of peripheral amino acid decarboxylase (AADC) have been
introduced to achieve proper LD concentration in the central nervous system
reducing systemic adverse events. Inhibitors of catechol-O-methyltransferase
(COMT) increased LD half-life and bioavailability. Efforts are still being made
to achieve a continuous dopaminergic stimulation, with the combination of oral
LD with an AADC inhibitor and a COMT inhibitor, or the intra-duodenal
water-based LD/ carbidopa gel. Further approaches to enhance LD efficacy are
focused on new non-oral administration routes, including nasal, intra-duodenal,
intrapulmonary (CVT-301) and subcutaneous (ND0612), as well as on novel ER
formulations, including IPX066, which recently concluded phase III trial.
CONCLUSION: New LD formulations, oral compounds as well as routes have been
tested in the last years, with two main targets: achieve continuous dopaminergic
stimulation and find an instant deliver route for LD. BACKGROUND: CVT-301, an inhaled levodopa (LD) formulation, is under development
for relief of OFF periods in Parkinson's disease (PD). Previously, we reported
that CVT-301 improved OFF symptoms relative to placebo. In this study, we
evaluate pulmonary function in patients treated with a single dose of CVT-301 or
placebo for 3 hours, or received multiple doses/day for 4 weeks.
METHODS: As part of two phase 2 studies, pulmonary safety and tolerability of
CVT-301 were evaluated in PD patients experiencing motor fluctuations (≥2 hours
OFF/day), Hoehn and Yahr stage 1-3, and forced expiratory volume in 1
second/forced vital capacity ratio ≥75% of predicted (in ON state). In study A,
patients received single doses of oral carbidopa/LD and each of the following
via the inhaled route: placebo and 25 and 50 mg LD fine particle dose (FPD)
CVT-301. In study B, patients received up to 3 inhaled doses/day of 35 mg (weeks
1-2) and 50 mg LD FPD CVT-301 (weeks 3-4) versus placebo. Assessments included
spirometry and treatment-emergent adverse events (TEAEs).
RESULTS: In study A, (n = 24) mean age ± standard deviation was 61.3 ± 7.4
years, mean time since diagnosis was 10.5 ± 4.6 years, and mean duration of LD
treatment 8.4 ± 3.7 years. Assessment of pulmonary function (predose to 3 hours
postdose) showed that spirometry findings were within normal ranges, regardless
of treatment groups, or motor status at screening. In study B, (n = 86) mean age
was 62.4 ± 8.7 years, time since PD diagnosis was 9.4 ± 3.9 years, and duration
of LD treatment 7.8 ± 3.9 years. Longitudinal assessment of pulmonary function
over 4 weeks showed no significant difference in spirometry between CVT-301
versus placebo groups. In both studies, the most common CVT-301 TEAE was
mild-to-moderate cough (study A: 21%; study B: 7% vs. 2% in placebo). Other
common TEAEs in study B were dizziness and nausea.
CONCLUSION: Acute and longitudinal assessment of pulmonary function showed that
CVT-301 treatment was not associated with acute airflow obstruction in this
population. CVT-301 was generally safe and well tolerated. Levodopa (LD), in combination with a decarboxylase inhibitor, is a mainstay and
the most effective therapeutic agent in the treatment of Parkinson's disease
(PD). Unfortunately, during chronic treatment with this agent, ON-OFF phenomena
and dyskinesia appear. Despite the many medical treatment options available,
unpredictable OFF episodes can still occur and be severe and disabling. A rescue
therapy that provides a rapid and predictable ON response for patients with OFF
periods would be of great value for such patients. Areas covered: CVT-301 is a
self-administered dry powder aerosol inhaled formulation of LD that is being
developed as a self-administered treatment for OFF periods. The PK profile of
CVT-301, the efficacy, and the safety highlighted in randomized clinical trials
will be reviewed. Expert opinion: CVT-301 may offer several potential advantages
including increased systemic bioavailability through pulmonary absorption, rapid
onset of action, avoidance of first-pass drug metabolism and less plasma-level
variability. List of Abbreviations: PD: Parkinson's disease; LD: Levodopa; CD:
Carbidopa; AADC: aromatic L-amino acid decarboxylase; IR: immediate-release;
FPD: fine particle dose; GI: gastrointestinal; PK: pharmacokinetic; CVs:
coefficient of variation; UPDRS: Unified Parkinson's Disease Rating Scale; AEs:
adverse events; FEV: forced expiratory volume; FVC: forced vital capacity; DLCO:
diffuse lung CO ; tmax: time to maximum concentration. |
Are there tools for visualizing and processing long-read sequencing data? | Yes. Tools such as NanoPack for instance have been developed for visualization and processing of long-read sequencing data from Oxford Nanopore Technologies and Pacific Biosciences. | SUMMARY: Here we describe NanoPack, a set of tools developed for visualization
and processing of long-read sequencing data from Oxford Nanopore Technologies
and Pacific Biosciences.
AVAILABILITY AND IMPLEMENTATION: The NanoPack tools are written in Python3 and
released under the GNU GPL3.0 License. The source code can be found at
https://github.com/wdecoster/opack, together with links to separate scripts
and their documentation. The scripts are compatible with Linux, Mac OS and the
MS Windows 10 subsystem for Linux and are available as a graphical user
interface, a web service at http://oplot.bioinf.be and command line tools.
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. |
Name siRNA drugs that have entered phase 2-3 clinical trials (by 2019). | siRNAs that have entered phase 2-3 clinical trials by 2019 include PF-04523655, TKM-080301, Atu027, SYL040012, SYL1001, siG12D-LODER (phase 2), QPI-1002, QPI-1007, and patisiran (phase 3). | Ten years after Fire and Melo's Nobel Prize for discovery of gene silencing by
double-stranded RNA, a remarkable progress was achieved in RNA interference
(RNAi). Changes in the chemical structure of synthetic oligonucleotides make
them more stable and specific, and new delivery strategies became progressively
available. The attention of pharmaceutical industry rapidly turned to RNAi, as
an opportunity to explore new drug targets. This review addresses nine
small-interfering RNAs (siRNAs) and one unique microRNA (miRNA) inhibitor, which
entered the phase 2-3 clinical trials. The siRNAs in focus are PF-04523655,
TKM-080301, Atu027, SYL040012, SYL1001, siG12D-LODER (phase 2), QPI-1002,
QPI-1007, and patisiran (phase 3). Regarding miRNAs, their content can be down-
or up-regulated, by using miRNA inhibitors (AntimiRs) or miRNA mimics.
Miravirsen is an AntimiR-122 for hepatitis C virus infection. The flexibility of
RNAi technology is easily understood taking into account: (i) the different drug
targets (i.e. p53, caspase 2, PKN3, β2-adrenergic receptor, mutated KRAS,
microRNAs); (ii) therapeutic conditions, including ophthalmic diseases, kidney
injury, amyloidosis, pancreatic cancer, viral hepatitis; and (iii) routes of
administration (ocular, intravenous, subcutaneous, intratumoral). Although some
issues are still matters of concern (delivery, toxicity, cost, and biological
barriers), RNAi definitively opens a wide avenue for drug development. |
Where is fatty acid binding protein 2 expressed? | fatty acid binding protein 2 is expressed by intestinal epithelial cells | The human intestinal fatty acid binding protein 2 (FABP2) mediates fat
absorption by binding and intracellular trafficking of long-chain free fatty
acids. Studies with knockout mice and association analysis of polymorphisms
revealed that FABP2 is a susceptibility gene for type 2 diabetes (noninsulin
dependent diabetes mellitus [NIDDM]) and related traits. Relevant FABP2 promoter
polymorphisms c.-80_-79insT (rs5861422), c.-136_-132delAGTAG (rs5861423),
c.-168_-166delAAGinsT (rs1973598), c.-260G>A (rs6857641), c.-471G>A (rs2282688),
and c.-778G>T (rs10034579) result in two haplotypes A and B, whereby B possesses
two- to three-fold lower transcriptional activity than A. We show in luciferase
reporter gene assays by a series of chimeric FABP2 promoter constructs in
intestinal Caco-2 cells that polymorphism c.-80_-79insT essentially determines
different activities of the FABP2 promoter. In accordance, in electrophoretic
mobility shift assays (EMSAs), transcriptional factors GATA-5 and -6 bind with
higher binding affinities to the FABP2 promoter region containing the -80A
allele compared to B. As functional consequence, haplotype A is twice as much
more activated by GATA factors than haplotype B in liver Huh7 cells.
Additionally, a construct bearing the -80B allele in the background of haplotype
A reversed the activity from A to B. Thus, the GATA mediated differential
activation of FABP2 haplotypes depends on polymorphism c.-80_-79insT. This
provides the molecular basis for the variant specific transcriptional regulation
of the diabetes type 2-associated FABP2 gene. The human fatty acid binding protein (FABP2) is involved in intestinal
absorption and intracellular trafficking of long-chain fatty acids. Here we
investigate transcriptional regulation of FABP2 by the endodermal hepatic
nuclear factor 1 alpha (HNF-1alpha). In electromobility shift and supershift
assays we show the presence of two adjacent HNF-1alpha binding sites within the
FABP2 promoter regions -185 to -165 and -169 to -149. HNF-1alpha activates an
FABP2 promoter luciferase construct by 3.5 and 20-fold in Caco-2 and Hela cells,
respectively. Mutational analysis of HNF-1alpha elements resulted in about 50%
reduction of basal and HNF-1alpha induced activity of FABP2 promoter constructs,
predomitly caused by deletion of the -185 to -165 site. Thus, our data
suggest a major role of HNF-1alpha in control of FABP2 expression in intestine
via a functional HNF-1alpha recognition element within FABP2 promoter region
-185 to -165. Variants of the human intestinal fatty acid binding protein 2 gene (FABP2) are
associated with traits of the metabolic syndrome. Relevant FABP2 promoter
polymorphisms c.-80_-79insT, c.-136_-132delAGTAG, c.-168_-166delAAGinsT,
c.-260G>A, c.-471G>A, and c.-778G>T result in two haplotypes A and B. Activation
of haplotypes by rosiglitazone stimulated PPARgamma/RXRalpha leads to 2-fold
higher activity of haplotype B than A. As shown by chimeric FABP2 promoter
constructs, the higher responsiveness of FABP2 haplotype B is mainly but not
solely determined by polymorphism c.-471G>A. As shown by EMSA and
promoter-reporter assays, Oct-1 interacts with the -471 region of FABP2
promoters, induces the activities of both FABP2 promoter haplotypes and
abolishes the different activities of haplotypes induced by rosiglitazone
activated PPARgamma/RXRalpha. In conclusion, our findings suggest a functional
role of PPARgamma/RXRalpha and Oct-1 in the regulation of the FABP2 gene. BACKGROUND: This meta-analysis aimed to determine the role of human fatty acid
binding protein 2 (FABP2) expression in the diagnosis of necrotizing
enterocolitis (NEC) of newborns.
DATA SOURCES: Eligible studies for further statistical analysis were identified
from various databases including PubMed, Expert Medica Database, Web of Science,
Cochrane Library, Google Scholar, China BioMedicine and China National Knowledge
Infrastructure. Random effects model was used, and summary standardized mean
difference (SMD) with its 95% confidence interval (CI) was calculated to assess
the association of FABP2 expression and NEC.
RESULTS: Ten articles which included 572 infants (262 infants with NEC and 310
healthy controls) were included in the current meta-analysis. FABP2 showed a
positive relationship with NEC of newborns (SMD=2.88, 95% CI=2.09-3.67,
P<0.001). And FABP2 expression was higher in patients with advanced stage of NEC
(stage III or stage II+III) than in those with early stage of NEC (stage I)
(SMD=-0.48, 95% CI=-0.87 to -0.09, P=0.015). Ethnicity-stratified analysis
yielded significantly different estimates with a high FABP2 expression in NEC in
both Caucasians (SMD=3.16, 95% CI=1.90-4.43, P<0.001) and Asians (SMD=2.57, 95%
CI=1.50-3.64, P<0.001). Sample-based subgroup analysis showed that FABP2
expression was positively correlated with neonatal NEC in both urinary- and
blood-sample subgroups (all P<0.05).
CONCLUSION: The results prove that the high FABP2 expression is related to the
damage to intestinal cells, which may be a possible early detection marker
identifying neonatal NEC. Small intestinal epithelial cells (IEC) play a major role in the absorption of
nutrients and toxins. Due to the similarity of genome-wide single copy protein
orthologues between cattle and human, establishment of rumit's primary small
IEC culture could be a valuable tool for toxicity studies. Therefore, the
current study focused on the development and characterization of buffalo IEC
culture, as cattle slaughter is banned in India. The buffalo jejunum fragments
were washed consecutively several times in saline, warm phosphate buffered
saline (PBS), PBS with 5 mM dithiothreitol, digesting solution and 2% sorbitol
in PBS. The cells were cultured on 17 µg/cm2 collagen coated plates and
transwell plates with serum (2% Fetal bovine serum (FBS) and 10% FBS) and
serum-free culture conditions. The cells were differentiated into typical
epithelial cobblestone morphology from day 5 onwards in 50% successful cultures.
The cultured IEC were characterized by gene expression of epithelial cell
markers, cytokeratin and vimentin, and enterocyte markers like villin, zonula
occluden (ZO1), fatty acid binding protein 2 (FABP2) and small intestinal
peptidase (IP). Based on the morphology and gene expression profile, 10% FBS has
been recommended for culturing primary buffalo IEC on collagen coated plates for
10 days. However, 50% of the successful cultures could not show epithelial
phenotype on 10% FBS culture conditions even on collagen coated plates.
Interestingly, undifferentiated IEC showed an increasing expression of FABP2, IP
and ZO1 transcripts compared to differentiated intestinal cells with 10% FBS on
collagen plates. Therefore, future studies are needed to understand the role of
FABP2, IP and ZO1 in differentiation of buffalo IEC. |
Which gene mutation is associated with Woodhouse Sakati syndrome? | DCAF17 mutations are associated with Woodhouse-Sakati syndrome, a rare disorder characterized by alopecia, hypogonadotropic hypogonadism, sensorineural hearing loss, diabetes mellitus, and extrapyramidal movements. | First described in 1983, Woodhouse-Sakati syndrome (WSS) is a rare autosomal
recessive genetic disorder that leads to a spectrum of hypogonadal symptoms in
adolescence. The responsible gene, DCAF17 located on chromosome 2q31.1, was
discovered in 2008 and to date nine mutations have been reported in the
literature. The aim of the study was to review WSS descriptively in the light of
new case reports with focus on endocrine features. Phenotypic description of
three patients (two females, one male) with WSS followed in the Endocrinology
Department of the University Hospital of Nancy, France, and exhaustive review of
the literature using the PUBMED database were performed. Of 72 patients from 29
families with documented WSS who were identified, 39 had undergone genetic
testing. WSS was invariably associated with hypogonadism, decreased IGF1 and
frontotemporal alopecia starting in childhood. In addition to this triad, some
patients exhibited intellectual disabilities of varying severity (87 %),
bilateral deafness (76 %), cervicofacial dystonia and limb pain (42 % of cases,
rising to 89 % after 25 years) and diabetes (66 %, rising to 96 % after
25 years). The pathophysiology of WSS remains unclear. Woodhouse Sakati syndrome (WSS, MIM 241080) is a rare autosomal recessive
genetic condition characterized by alopecia, hypogonadism, hearing impairment,
diabetes mellitus, learning disabilities and extrapydamidal manifestations.
Sequence variants in the gene DCAF17, encoding nucleolar substrate receptor,
were identified as the underlying cause of inherited WSS. Considerable
phenotypic heterogeneity exists in WSS with regard to severity, organs
involvement and age of onset, both in inter-familial and intra-familial cases.
In this study, the genetic characterization of a consanguineous pedigree showing
mild features of WSS was performed, followed by structural analysis of truncated
protein. Exome sequencing identified a novel single base deletion variant
(c.270delA; K90Nfs8*) in third exon of the gene DCAF17 (RefSeq; NM_025000),
resulting in a truncated protein. Structural analysis of truncated DCAF17
revealed absence of amino acid residues crucial for interaction with DDB1. Taken
together, the data confirmed the single base pair deletion as the underlying
cause of this second report of WSS from Pakistan. This signifies the vital yet
unexplored role of DCAF17 both in development and maintece of adult tissues
homeostasis. Two consanguineous Qatari siblings presented for evaluation: a 17-4/12-year-old
male with hypogonadotropic hypogonadism, alopecia, intellectual disability, and
microcephaly and his 19-year-old sister with primary amenorrhea, alopecia, and
normal cognition. Both required hormone treatment to produce secondary sex
characteristics and pubertal development beyond Tanner 1. SNP array analysis of
both probands was performed to detect shared regions of homozygosity which may
harbor homozygous mutations in a gene causing their common features of abnormal
pubertal development, alopecia, and variable cognitive delay. Our patients
shared multiple homozygous genomic regions; ten shared regions were >1 Mb in
length and constituted 0.99% of the genome. DCAF17, encoding a transmembrane
nuclear protein of uncertain function, was the only gene identified in a
homozygous region known to cause hypogonadotropic hypogonadism. DCAF17 mutations
are associated with Woodhouse-Sakati syndrome, a rare disorder characterized by
alopecia, hypogonadotropic hypogonadism, sensorineural hearing loss, diabetes
mellitus, and extrapyramidal movements. Sequencing of the coding exons and
flanking intronic regions of DCAF17 in the proband revealed homozygosity for a
previously described founder mutation (c.436delC). Targeted DCAF17 sequencing of
his affected sibling revealed the same homozygous mutation. This family
illustrates the utility of SNP array testing in consanguineous families to
efficiently and inexpensively identify regions of genomic homozygosity in which
genetic candidates for recessive conditions can be identified. BACKGROUND Woodhouse-Sakati syndrome (WSS) is a rare autosomal recessive genetic
condition that was first described in 1983. Since its original description,
approximately 50 cases have been reported with various clinical signs and
symptoms. Characteristics include progressive neurologic deterioration with
extrapyramidal involvement and polyendocrinopathy most notable for hypogonadism
starting in early adolescence. Clinical presentation is variable, and a subset
of patients may have additional features, such as premature aging, alopecia,
distinctive facial features, cognitive impairment, or deafness. CASE REPORT We
illustrate the phenotypic variability of 5 patients with WSS due to the
previously reported homozygous single nucleotide deletion c.436delC in the
DCAF17 gene, identified in 2008. Despite identical genetic alteration, our 5
patients had various clinical features among them and compared with previously
reported cases with the same pathogenic mutation. CONCLUSIONS The phenotypic
variability of WSS due to c.436delC founder mutation may have a wider range than
previously recognized. BACKGROUND AND PURPOSE: Woodhouse-Sakati syndrome is a rare autosomal recessive
disorder characterized by hypogonadism, alopecia, diabetes mellitus, and
progressive extrapyramidal signs. The disease is caused by biallelic pathogenic
variants in the DCAF17 gene. The purpose of this study was to describe the
spectrum of brain MR imaging abnormalities in Woodhouse-Sakati syndrome.
MATERIALS AND METHODS: We reviewed brain MR images of 26 patients with a
clinical and genetic diagnosis of Woodhouse-Sakati syndrome (12 males, 14
females; age range, 16-45 years; mean age, 26.6 years). Follow-up studies were
conducted for 6 patients.
RESULTS: All patients had abnormal MR imaging findings. The most common
abnormalities were a small pituitary gland (76.9%), pronounced basal ganglia
iron deposition (73%), and white matter lesions in 69.2%. White matter lesions
showed frontoparietal and periventricular predomice. All white matter lesions
spared subcortical U-fibers and were nonenhanced. Prominent perivascular spaces
(15.3%) and restricted diffusion in the splenium of the corpus callosum (7.6%)
were less frequent findings. Follow-up studies showed expansion of white matter
lesions with iron deposition further involving the red nucleus and substantia
nigra. Older age was associated with a more severe degree of white matter
lesions (P < .001).
CONCLUSIONS: Small pituitary gland, accentuated iron deposition in the globus
pallidus, and nonenhancing frontoparietal/periventricular white matter lesions
were the most noted abnormalities seen in our cohort. The pattern and extent of
these findings were observed to correlate with older age, reflecting a possible
progressive myelin destruction and/or axonal loss. The presence of pituitary
hypoplasia and white matter lesions can further distinguish Woodhouse-Sakati
syndrome from other neurodegenerative diseases with brain iron accumulation
subtypes. |
Mention computational tools that have been developed for alternative polyadenylation (APA) sites analysis | TAPAS, PlantAPA and IntMAP | Polyadenylation [poly(A)] is an essential process during the maturation of most
mRNAs in eukaryotes. Alternative polyadenylation (APA) as an important layer of
gene expression regulation has been increasingly recognized in various species.
Here, a web platform for visualization and analysis of alternative
polyadenylation (VAAPA) was developed. This platform can visualize the
distribution of poly(A) sites and poly(A) clusters of a gene or a section of a
chromosome. It can also highlight genes with switched APA sites among different
conditions. VAAPA is an easy-to-use web-based tool that provides functions of
poly(A) site query, data uploading, downloading, and APA sites visualization. It
was designed in a multi-tier architecture and developed based on Smart GWT
(Google Web Toolkit) using Java as the development language. VAAPA will be a
valuable addition to the community for the comprehensive study of APA, not only
by making the high quality poly(A) site data more accessible, but also by
providing users with numerous valuable functions for poly(A) site analysis and
visualization. Alternative polyadenylation (APA) is an important layer of gene regulation that
produces mRNAs that have different 3' ends and/or encode diverse protein
isoforms. Up to 70% of annotated genes in plants undergo APA. Increasing numbers
of poly(A) sites collected in various plant species demand new methods and tools
to access and mine these data. We have created an open-access web service called
PlantAPA (http://bmi.xmu.edu.cn/plantapa) to visualize and analyze genome-wide
poly(A) sites in plants. PlantAPA provides various interactive and dynamic
graphics and seamlessly integrates a genome browser that can profile
heterogeneous cleavage sites and quantify expression patterns of poly(A) sites
across different conditions. Particularly, through PlantAPA, users can analyze
poly(A) sites in extended 3' UTR regions, intergenic regions, and ambiguous
regions owing to alternative transcription or RNA processing. In addition, it
also provides tools for analyzing poly(A) site selections, 3' UTR lengthening or
shortening, non-canonical APA site switching, and differential gene expression
between conditions, making it more powerful for the study of APA-mediated gene
expression regulation. More importantly, PlantAPA offers a bioinformatics
pipeline that allows users to upload their own short reads or ESTs for poly(A)
site extraction, enabling users to further explore poly(A) site selection using
stored PlantAPA poly(A) sites together with their own poly(A) site datasets. To
date, PlantAPA hosts the largest database of APA sites in plants, including
Oryza sativa, Arabidopsis thaliana, Medicago truncatula, and Chlamydomonas
reinhardtii. As a user-friendly web service, PlantAPA will be a valuable
addition to the community of biologists studying APA mechanisms and gene
expression regulation in plants. MOTIVATION: The length of the 3' untranslated region (3' UTR) of an mRNA is
essential for many biological activities such as mRNA stability, sub-cellular
localization, protein translation, protein binding and translation efficiency.
Moreover, correlation between diseases and the shortening (or lengthening) of 3'
UTRs has been reported in the literature. This length is largely determined by
the polyadenylation cleavage site in the mRNA. As alternative polyadenylation
(APA) sites are common in mammalian genes, several tools have been published
recently for detecting APA sites from RNA-Seq data or performing
shortening/lengthening analysis. These tools consider either up to only two APA
sites in a gene or only APA sites that occur in the last exon of a gene,
although a gene may generally have more than two APA sites and an APA site may
sometimes occur before the last exon. Furthermore, the tools are unable to
integrate the analysis of shortening/lengthening events with APA site detection.
RESULTS: We propose a new tool, called TAPAS, for detecting novel APA sites from
RNA-Seq data. It can deal with more than two APA sites in a gene as well as APA
sites that occur before the last exon. The tool is based on an existing method
for finding change points in time series data, but some filtration techniques
are also adopted to remove change points that are likely false APA sites. It is
then extended to identify APA sites that are expressed differently between two
biological samples and genes that contain 3' UTRs with shortening/lengthening
events. Our extensive experiments on simulated and real RNA-Seq data demonstrate
that TAPAS outperforms the existing tools for APA site detection or
shortening/lengthening analysis significantly.
AVAILABILITY AND IMPLEMENTATION: https://github.com/arefeen/TAPAS.
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. |
What is patisiran? | Patisiran (ONPATTRO™) is a double-stranded small interfering RNA encapsulated in a lipid nanoparticle for delivery to hepatocytes. By specifically binding to a genetically conserved sequence in the 3' untranslated region of mutant and wild-type transthyretin (TTR) messenger RNA, patisiran causes its degradation (via RNA interference) and subsequently a reduction in serum TTR protein levels and tissue TTR protein deposits. It has been approved in the USA for the treatment of the polyneuropathy of hereditary TTR-mediated amyloidosis (hATTR) in adults and subsequently approved in the EU for the treatment of hATTR in adults with stage 1 or 2 polyneuropathy. | |
Losigamone can be used for treatment of which disease? | Losigamone is sometimes used as an add-on therapy for epilepsy. | Patients with drug resistant epilepsy represent about 40% of the whole
population of epileptic patients. These patients require more than one
antiepileptic drug. In animal models of epilepsy, it is possible to determine
which combinations produce supra-additive anticonvulsive effects with minimal or
even no adverse reactions. The experimental data can be helpful for predicting
effective drug combinations in patients with refractory epilepsy. Losigamone is
a new antiepileptic drug with an unknown mechanism of action. The drug belongs
to the group of beta-methoxy-butenolides, and exists as a racemic mixture of two
etiomers (AO-242 and AO-294). The drug is eliminated by oxidation. Cytochrome
CYP2A6 appears to be the main isoenzyme responsible for the metabolism of
losigamone. In vitro, losigamone exerts anticonvulsant activity in the
picrotoxin model in CA1 and CA3 hippocampal areas, the low Ca(2+) model in CA1
area and the low Mg(2+) model in the entorhinal cortex and hippocampus. In vivo,
the drug exhibits significant efficacy against maximal electroshock-induced
seizures in rodents and pentetrazole-induced clonic convulsions in mice. Potency
of losigamone varies with the respective seizure test, animal species used in
experiments and route of drug administration. Toxicity studies do not indicate
any teratogenic risk of the drug, at least in animals. In clinical trial,
losigamone proved to have satisfactory effectiveness and good tolerance in the
treatment of partial and secondary generalized seizures. The etiomer AO-242
seems to be more potent than AO-294 or racemate. OBJECTIVES: The influence of the new antiepileptic drug losigamone (CAS
112856-44-7/123783-52-8) on the pharmacokinetics of a combined oral
contraceptive containing ethinylestradiol (CAS 57-63-6) and levonorgestrel (CAS
797-63-7) was investigated in 16 healthy women.
METHODS: This phase I study consisted of 3 periods with an uncontrolled first
period and a double-blind, placebo-controlled, cross-over design in the second
and third period. All subjects received a single dose of 200 mg losigamone (1
tablet) in period 1 (on day 14) as well as multiple doses of losigamone (3
tablets = 600 mg per day) or placebo for 15 days in periods 2 and 3. During all
three periods an oral contraceptive containing 30 microg ethinylestradiol and
150 microg levonorgestrel was given. Single-dose pharmacokinetics was
investigated on day 14 of period 1. Multiple-dose pharmacokinetic investigations
were performed on day 15 of periods 2 and 3. The samples were assayed to derive
pharmacokinetic data of ethinylestradiol and levonorgestrel. In addition, the
concentrations of losigamone racemate (AO-33) and its etiomers AO-242 and
AO-294 were determined in these samples.
RESULTS: The mean values of the pharmacokinetic parameters AUC and Cmax of
ethinylestradiol and levonorgestrel after multiple-dose treatment with
losigamone or placebo were quite similar and met the criteria for
bioequivalence. The 90% confidence intervals of the log-transformed ratios of
the geometric means of the primary pharmacokinetic variables were included in
the respective acceptance ranges of 80% to 125% (AUC) and 70% to 143% (Cmax).
CONCLUSIONS: The study demonstrated that multiple doses of losigamone did not
influence the multiple dose kinetics of ethinylestradiol and levonorgestrel. The
single- and multiple-dose kinetics of 200 mg losigamone and its etiomeres did
not differ from each other in a significant way. The combination of losigamone
and the combined oral contraceptive was well tolerated and no serious adverse
events occurred. It can be stated that the antiepileptic drug losigamone and the
combined contraceptive do not interact each others metabolism. Epilepsy is one of the most prevalent neurological syndromes in the world today.
Epilepsy describes a group of brain disorders whose symptoms and causes are
diverse and complicated, but all share a common behavioural manifestation: the
seizure. Seizures result from the abnormal discharge of groups of neurons within
the brain, usually within a focal point, that can result in the recruitment of
large brain regions into epileptiform activity. Although the range of
explanations for the development of seizures can be as varied as genetic
composition to acute head trauma, the net result is often similar. The
excitability of neurons is governed by the input they receive from their
neighbours and the intrinsic excitability of the neuron. In this review we focus
on elements that are crucial to determining the intrinsic excitability of
neurons in the CNS, the voltage gated ion channels (VGICs). VGICs as well as
being important for physiological function are critical in producing
hyperexcitability such as that associated with seizure discharges. Many drugs
routinely used in the clinical setting, as well as several novel experimental
drugs, have shown interactions with VGICs that underpin, at least in part, their
anticonvulsant action. We review the physiological roles of voltage gated ion
channels that are selective for sodium, potassium and calcium conductance and
attempt to highlight their role in the pathology of epilepsy. This is
supplemented by the mechanisms of drug action at these important anticonvulsant
targets for classical and clinically relevant compounds (e.g. phenytoin,
ethosuximide) as well as some important second generation drugs (e.g.
gabapentin, levetiracetam) and novel experimental agents (e.g. retigabine,
losigamone, safinamide). We also briefly discuss the urgent need for new drugs
in this arena and the potential of combinatorial methods and recombit
screening to identify leads. As an extension of a previous validation study, the concentration-dependent
effects of a series of anticonvulsant drugs were examined in aggregating cell
cultures of foetal rat telencephalon. Cultures were treated either at an early
(day 5 to day 14) or at an advanced (day 20 to day 28) developmental stage, and
assayed for changes in the activities of the cell type-specific enzymes choline
acetyltransferase (ChAT), acetylcholinesterase (AChE), glutamic acid
decarboxylase (GAD), glutamine synthetase (GS) and 2',3'-cyclic nucleotide
3'-phosphohydrolase (CNP). Five drugs (carbamazepine, diazepam, phenobarbital,
phenytoin and valproate), currently used in the treatment of epileptic patients,
were tested together with losigamone, a recently developed anticonvulsant. The
results show distinct, concentration-dependent patterns of biochemical changes
for the different drugs. Phenytoin, carbamazepine, losigamone and diazepam
greatly reduced GAD, ChAT and AChE activities, indicating a relatively high
neuron-specific toxic potential. Diazepam produced a more general pattern of
toxicity and, in contrast to the anticonvulsants, showed higher toxicity in
less-differentiated cultures. Phenobarbital and valproate slightly but
significantly increased the activities of several enzymes. The patterns of
concentration-dependent effects observed in this three-dimensional cell culture
system are in good agreement with the presumed neurotoxic and/or teratogenic
potential of these drugs. INTRODUCTION: About 3% of people will be diagnosed with epilepsy during their
lifetime, but about 70% of people with epilepsy eventually go into remission.
METHODS AND OUTCOMES: We conducted a systematic review and aimed to answer the
following clinical questions: What are the effects of starting antiepileptic
drug treatment following a single seizure? What are the effects of drug
monotherapy in people with partial epilepsy? What are the effects of additional
drug treatments in people with drug-resistant partial epilepsy? What is the risk
of relapse in people in remission when withdrawing antiepileptic drugs? What are
the effects of behavioural and psychological treatments for people with
epilepsy? What are the effects of surgery in people with drug-resistant temporal
lobe epilepsy? We searched: Medline, Embase, The Cochrane Library, and other
important databases up to July 2009 (Clinical Evidence reviews are updated
periodically; please check our website for the most up-to-date version of this
review). We included harms alerts from relevant organisations such as the US
Food and Drug Administration (FDA) and the UK Medicines and Healthcare products
Regulatory Agency (MHRA).
RESULTS: We found 83 systematic reviews, RCTs, or observational studies that met
our inclusion criteria. We performed a GRADE evaluation of the quality of
evidence for interventions.
CONCLUSIONS: In this systematic review we present information relating to the
effectiveness and safety of the following interventions: antiepileptic drugs
after a single seizure; monotherapy for partial epilepsy using carbamazepine,
gabapentin, lamotrigine, levetiracetam, phenobarbital, phenytoin, sodium
valproate, or topiramate; addition of second-line drugs for drug-resistant
partial epilepsy (allopurinol, eslicarbazepine, gabapentin, lacosamide,
lamotrigine, levetiracetam, losigamone, oxcarbazepine, retigabine, tiagabine,
topiramate, vigabatrin, or zonisamide); antiepileptic drug withdrawal for people
with partial or generalised epilepsy who are in remission; behavioural and
psychological treatments for partial or generalised epilepsy (biofeedback,
cognitive behavioural therapy (CBT), educational programmes, family counselling,
relaxation therapy (alone or plus behavioural modification therapy, yoga); and
surgery for drug-resistant temporal lobe epilepsy ( lesionectomy, temporal
lobectomy, vagus nerve stimulation as adjunctive therapy). INTRODUCTION: About 3% of people will be diagnosed with epilepsy during their
lifetime, but about 70% of people with epilepsy eventually go into remission.
METHODS AND OUTCOMES: We conducted a systematic review and aimed to answer the
following clinical questions: What are the effects of starting antiepileptic
drug treatment following a single seizure? What are the effects of drug
monotherapy in people with partial epilepsy? What are the effects of additional
drug treatments in people with drug-resistant partial epilepsy? What is the risk
of relapse in people in remission when withdrawing antiepileptic drugs? What are
the effects of behavioural and psychological treatments for people with
epilepsy? What are the effects of surgery in people with drug-resistant temporal
lobe epilepsy? We searched: Medline, Embase, The Cochrane Library, and other
important databases up to July 2009 (Clinical Evidence reviews are updated
periodically; please check our website for the most up-to-date version of this
review). We included harms alerts from relevant organisations such as the US
Food and Drug Administration (FDA) and the UK Medicines and Healthcare products
Regulatory Agency (MHRA).
RESULTS: We found 83 systematic reviews, RCTs, or observational studies that met
our inclusion criteria. We performed a GRADE evaluation of the quality of
evidence for interventions.
CONCLUSIONS: In this systematic review we present information relating to the
effectiveness and safety of the following interventions: antiepileptic drugs
after a single seizure; monotherapy for partial epilepsy using carbamazepine,
gabapentin, lamotrigine, levetiracetam, phenobarbital, phenytoin, sodium
valproate, or topiramate; addition of second-line drugs for drug-resistant
partial epilepsy (allopurinol, eslicarbazepine, gabapentin, lacosamide,
lamotrigine, levetiracetam, losigamone, oxcarbazepine, retigabine, tiagabine,
topiramate, vigabatrin, or zonisamide); antiepileptic drug withdrawal for people
with partial or generalised epilepsy who are in remission; behavioural and
psychological treatments for partial or generalised epilepsy (biofeedback,
cognitive behavioural therapy (CBT), educational programmes, family counselling,
relaxation therapy (alone or plus behavioural modification therapy, yoga); and
surgery for drug-resistant temporal lobe epilepsy ( lesionectomy, temporal
lobectomy, vagus nerve stimulation as adjunctive therapy). BACKGROUND: Epilepsy is a common neurologic disorder, affecting approximately 50
million people worldwide; nearly a third of these people are not well controlled
by a single antiepileptic drug and usually require treatment with a combination
of two or more antiepileptic drugs. In recent years, many newer antiepileptic
drugs have been investigated as add-on therapy for partial epilepsy; losigamone
is one of these drugs and is the focus of this systematic review.
OBJECTIVES: To investigate the efficacy and safety of losigamone when used as an
add-on therapy for partial epilepsy.
SEARCH METHODS: We searched the Cochrane Epilepsy Group Specialized Register (1
May 2012), the Cochrane Central Register of Controlled Trials (CENTRAL Issue 4
of 12, The Cochrane Library, 2012) and MEDLINE (1 May 2012). We searched trials
registers and contacted the manufacturer of losigamone and authors of included
studies for additional information. There were no language restrictions.
SELECTION CRITERIA: Randomized controlled add-on trials comparing losigamone
with placebo for partial epilepsy.
DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial
quality and extracted data. The primary outcomes were 50% or greater reduction
in seizure frequency and seizure freedom; the secondary outcomes were treatment
withdrawal and adverse events. Results are presented as risk ratios (RR) with
95% confidence intervals (CIs) or 99% CIs (for the individual listed adverse
events to make an allowance for multiple testing).
MAIN RESULTS: Two trials involving a total of 467 patients were eligible for
inclusion. Both trials assessed losigamone 1200 or 1500 mg/d as an add-on
therapy for partial epilepsy. One trial was assessed as being of good
methodologic quality while the other was of uncertain quality. For the efficacy
outcomes, results did show patients taking losigamone were significantly more
likely to achieve a 50% or greater reduction in seizure frequency (RR 1.75; 95%
CI 1.14 to 2.72), but associated with a significant increase of treatment
withdrawal when compared with those taking placebo (RR 2.16; 95% CI 1.28 to
3.67). For the safety outcomes, results indicated the proportion of patients who
experienced adverse events in the losigamone group was higher than the placebo
group (RR 1.34; 95% CI 1.00 to 1.80), dizziness was the only adverse event
significantly in relation to losigamone (RR 3.82; 99% CI 1.69 to 8.64). The
proportion of patients achieving seizure freedom was not reported in either
trial report. A subgroup analysis according to different doses of losigamone
showed that a higher dose of losigamone (1500 mg/d) is associated with a greater
reduction in seizure frequency than lower doses, but is also associated with
more dropouts due to adverse events.
AUTHORS' CONCLUSIONS: The results of this review showed losigamone can reduce
seizure frequency but was associated with more treatment withdrawals when used
as an add-on therapy for people with partial epilepsy. However, trials included
were of short-term duration and uncertain quality. Future well-designed
randomized, double-blind, placebo-controlled trials with a longer-term duration
are needed. The GABAA receptor (GABAAR) is a major target of antiseizure drugs (ASDs). A
variety of agents that act at GABAARs s are used to terminate or prevent
seizures. Many act at distinct receptor sites determined by the subunit
composition of the holoreceptor. For the benzodiazepines, barbiturates, and
loreclezole, actions at the GABAAR are the primary or only known mechanism of
antiseizure action. For topiramate, felbamate, retigabine, losigamone and
stiripentol, GABAAR modulation is one of several possible antiseizure
mechanisms. Allopregolone, a progesterone metabolite that enhances GABAAR
function, led to the development of ganaxolone. Other agents modulate GABAergic
"tone" by regulating the synthesis, transport or breakdown of GABA. GABAAR
efficacy is also affected by the transmembrane chloride gradient, which changes
during development and in chronic epilepsy. This may provide an additional
target for "GABAergic" ASDs. GABAAR subunit changes occur both acutely during
status epilepticus and in chronic epilepsy, which alter both intrinsic GABAAR
function and the response to GABAAR-acting ASDs. Manipulation of subunit
expression patterns or novel ASDs targeting the altered receptors may provide a
novel approach for seizure prevention. BACKGROUND: Epilepsy is a common neurologic disorder, affecting approximately 50
million people worldwide; nearly a third of these people are not well controlled
by a single antiepileptic drug (AED) and usually require treatment with a
combination of two or more AEDs. In recent years, many newer AEDs have been
investigated as add-on therapy for partial epilepsy; losigamone is one of these
drugs and is the focus of this systematic review. This is an update of a
Cochrane review first published in 2012 (Cochrane Database of Systematic Reviews
2012, Issue 6).
OBJECTIVES: To investigate the efficacy and safety of losigamone when used as an
add-on therapy for partial epilepsy.
SEARCH METHODS: We searched the Cochrane Epilepsy Group Specialized Register (16
February 2015), the Cochrane Central Register of Controlled Trials (CENTRAL, The
Cochrane Library 16 February 2015) and MEDLINE (Ovid, 1946 to 16 February 2015).
We searched trials registers and contacted the manufacturer of losigamone and
authors of included studies for additional information. We did not impose any
language restrictions.
SELECTION CRITERIA: Randomized controlled, add-on trials comparing losigamone
with placebo for partial epilepsy.
DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial
quality and extracted data. The primary outcomes were 50% or greater reduction
in seizure frequency and seizure freedom; the secondary outcomes were treatment
withdrawal and adverse events. Results are presented as risk ratios (RRs) with
95% confidence intervals (CIs) or 99% CIs (for the individual listed adverse
events to make an allowance for multiple testing).
MAIN RESULTS: Two trials involving a total of 467 patients, aged over 18 years,
were eligible for inclusion. Both trials assessed losigamone 1200 mg/day or 1500
mg/day as an add-on therapy for partial epilepsy. One trial was assessed as
being of good methodological quality while the other was of uncertain quality.
For the efficacy outcomes, results did show patients taking losigamone were
significantly more likely to achieve a 50% or greater reduction in seizure
frequency (RR 1.76; 95% CI 1.14 to 2.72), but associated with a significant
increase of treatment withdrawal when compared with those taking placebo (RR
2.16; 95% CI 1.28 to 3.67). For the safety outcomes, results indicated the
proportion of patients who experienced adverse events in the losigamone group
was higher than the placebo group (RR 1.34; 95% CI 1.00 to 1.80), dizziness was
the only adverse event significantly reported in relation to losigamone (RR
3.82; 99% CI 1.69 to 8.64). The proportion of patients achieving seizure freedom
was not reported in either trial report. A subgroup analysis according to
different doses of losigamone showed that a higher dose of losigamone (1500
mg/day) was associated with a greater reduction in seizure frequency than lower
doses, but was also associated with more dropouts due to adverse events.
AUTHORS' CONCLUSIONS: The results of this review showed losigamone did reduce
seizure frequency but was associated with more treatment withdrawals when used
as an add-on therapy for people with partial epilepsy. However, trials included
were of short-term duration and uncertain quality. Future well-designed
randomized, double-blind, placebo-controlled trials with a longer-term duration
are needed. No new studies have been found since the last version of this
review. |
Which curated data resources for ChIP-seq data are available? | The MGA repository, Cistrome Data Browser, CR Cistrome and GeneProf data. | GeneProf Data (http://www.geneprof.org) is an open web resource for analysed
functional genomics experiments. We have built up a large collection of
completely processed RNA-seq and ChIP-seq studies by carefully and transparently
reanalysing and annotating high-profile public data sets. GeneProf makes these
data instantly accessible in an easily interpretable, searchable and reusable
manner and thus opens up the path to the advantages and insights gained from
genome-scale experiments to a broader scientific audience. Moreover, GeneProf
supports programmatic access to these data via web services to further
facilitate the reuse of experimental data across tools and laboratories. Diversified histone modifications (HMs) are essential epigenetic features. They
play important roles in fundamental biological processes including
transcription, DNA repair and DNA replication. Chromatin regulators (CRs), which
are indispensable in epigenetics, can mediate HMs to adjust chromatin structures
and functions. With the development of ChIP-Seq technology, there is an
opportunity to study CR and HM profiles at the whole-genome scale. However, no
specific resource for the integration of CR ChIP-Seq data or CR-HM ChIP-Seq
linkage pairs is currently available. Therefore, we constructed the CR Cistrome
database, available online at http://compbio.tongji.edu.cn/cr and
http://cistrome.org/cr/, to further elucidate CR functions and CR-HM linkages.
Within this database, we collected all publicly available ChIP-Seq data on CRs
in human and mouse and categorized the data into four cohorts: the reader,
writer, eraser and remodeler cohorts, together with curated introductions and
ChIP-Seq data analysis results. For the HM readers, writers and erasers, we
provided further ChIP-Seq analysis data for the targeted HMs and schematized the
relationships between them. We believe CR Cistrome is a valuable resource for
the epigenetics community. Author information:
(1)Clinical Translational Research Center, Shanghai Pulmonary Hospital, Tongji
University, Shanghai 200433, China.
(2)Department of Bioinformatics, School of Life Sciences and Technology, Tongji
University, Shanghai 200092, China.
(3)Department of Biostatistics and Computational Biology, Dana-Farber Cancer
Institute and Harvard T.H. Chan School of Public Health, Boston, MA 02215, USA.
(4)Center for Functional Cancer Epigenetics, Dana-Farber Cancer Institute,
Boston, MA 02215, USA.
(5)MOE Key Laboratory of Bioinformatics, Bioinformatics Division and Center for
Synthetic & Systems Biology, TNLIST; Department of Automation, Tsinghua
University, Beijing 100084, China.
(6)Department of Biochemistry, University at Buffalo, Buffalo, NY 14214, USA.
(7)Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard
Medical School, Boston, MA 02215, USA.
(8)Department of Biostatistics and Computational Biology, Dana-Farber Cancer
Institute and Harvard T.H. Chan School of Public Health, Boston, MA 02215, USA
[email protected].
(9)Clinical Translational Research Center, Shanghai Pulmonary Hospital, Tongji
University, Shanghai 200433, China [email protected]. |
How many pseudokinases are there in the human kinome? | There are approximately 50 pseudokinases in the human kinome. | The human protein kinome comprises 535 proteins that, with the exception of
approximately 50 pseudokinases, control intracellular signaling networks by
catalyzing the phosphorylation of multiple protein substrates. While a major
research focus of the last 30 years has been cancer-associated Tyr and Ser/Thr
kinases, over 85% of the kinome has been identified to be dysregulated in at
least one disease or developmental disorder. Despite this remarkable statistic,
for the majority of protein kinases and pseudokinases, there are currently no
inhibitors progressing toward the clinic, and in most cases, details of their
physiologic and pathologic mechanisms remain at least partially obscure. By
curating and annotating data from the literature and major public databases of
phosphorylation sites, kinases, and disease associations, we generate an
unbiased resource that highlights areas of unmet need within the kinome. We
discuss strategies and challenges associated with characterizing catalytic and
noncatalytic outputs in cells, and describe successes and new frontiers that
will support more comprehensive cancer-targeting and therapeutic evaluation in
the future. Cancer Res; 78(1); 15-29. ©2017 AACR. |
What is the mechanism of action of Inclisiran? | Inclisiran, a novel, synthetic, siRNA molecule, inhibits PCSK9 synthesis in hepatocytes. Inclisiran targets intracellular PCSK9 synthesis specifically, resulting in a dose-dependent, long-term, significant reduction in LDL-C. | BACKGROUND: Inclisiran (ALN-PCSsc) is a long-acting RNA interference (RNAi)
therapeutic agent that inhibits the synthesis of proprotein convertase
subtilisin-kexin type 9 (PCSK9), a target for the lowering of low-density
lipoprotein (LDL) cholesterol.
METHODS: In this phase 1 trial, we randomly assigned healthy volunteers with an
LDL cholesterol level of at least 100 mg per deciliter in a 3:1 ratio to receive
a subcutaneous injection of inclisiran or placebo in either a
single-ascending-dose phase (at a dose of 25, 100, 300, 500, or 800 mg) or a
multiple-dose phase (125 mg weekly for four doses, 250 mg every other week for
two doses, or 300 or 500 mg monthly for two doses, with or without concurrent
statin therapy); each dose cohort included four to eight participants. Safety,
the side-effect profile, and pharmacodynamic measures (PCSK9 level, LDL
cholesterol level, and exploratory lipid variables) were evaluated.
RESULTS: The most common adverse events were cough, musculoskeletal pain,
nasopharyngitis, headache, back pain, and diarrhea. All the adverse events were
mild or moderate in severity. There were no serious adverse events or
discontinuations due to adverse events. There was one grade 3 elevation in the
γ-glutamyltransferase level, which was considered by the investigator to be
related to statin therapy. In the single-dose phase, inclisiran doses of 300 mg
or more reduced the PCSK9 level (up to a least-squares mean reduction of 74.5%
from baseline to day 84), and doses of 100 mg or more reduced the LDL
cholesterol level (up to a least-squares mean reduction of 50.6% from baseline).
Reductions in the levels of PCSK9 and LDL cholesterol were maintained at day 180
for doses of 300 mg or more. All multiple-dose regimens reduced the levels of
PCSK9 (up to a least-squares mean reduction of 83.8% from baseline to day 84)
and LDL cholesterol (up to a least-squares mean reduction of 59.7% from baseline
to day 84).
CONCLUSIONS: In this phase 1 trial, no serious adverse events were observed with
inclisiran. Doses of 300 mg or more (in single or multiple doses) significantly
reduced levels of PCSK9 and LDL cholesterol for at least 6 months. (Funded by
Alnylam Pharmaceuticals and the Medicines Company; ClinicalTrials.gov number,
NCT02314442 .). The identification of the critical role of proprotein convertase
subtilisin/kexin type 9 (PCSK9) has rapidly led to the development of PCSK9
inhibition with monoclonal antibodies (mAbs). PCSK9 mAbs are already in limited
clinical use and are the subject of major cardiovascular outcomes trials, which,
if universally positive, could see much wider clinical application of these
agents. Patients with familial hypercholesterolaemia are the most obvious
candidates for these drugs, but other patients with elevated cardiovascular
risk, statin intolerance or hyperlipoproteinaemia(a) may also benefit. PCSK9
mAbs, administered once or twice monthly, reduce LDL cholesterol levels by 50%
to 70%, and appear to be safe and acceptable to patients over at least 2 years
of treatment; however, treatment-emergent adverse effects are not always
identified in clinical trials, as well-evidenced by statin myopathy. Inclisiran
is a promising RNA-based therapy that promotes the degradation of PCSK9 mRNA
transcripts and has similar efficacy to mAbs, but with a much longer duration of
action. The cost-effectiveness and long-term safety of therapies targeted at
inhibiting PCSK9 remain to be demonstrated if they are to be used widely in
coronary prevention. Over the last 3 decades, hypolipidaemic treatment has significantly reduced both
Cardiovascular (CV) risk and events, with statins being the cornerstone of this
achievement. Nevertheless, residual CV risk and unmet goals in hypolipidaemic
treatment make novel options necessary. Recently marketed monoclonal antibodies
against proprotein convertase subtilisin/kexin type 9 (PCSK9) have shown the way
towards innovation, while other ways of PCSK9 inhibition like small interfering
RNA (Inclisiran) are already being tested. Other effective and well tolerated
drugs affect known paths of lipid synthesis and metabolism, such as bempedoic
acid blocking acetyl-coenzyme A synthesis at a different level than statins,
pemafibrate selectively acting on peroxisome proliferator-activated receptor
(PPAR)- alpha receptors and oligonucleotides against apolipoprotein (a).
Additionally, other novel hypolipidaemic drugs are in early phase clinical
trials, such as the inhibitors of apolipoprotein C-III, which is located on
triglyceride (TG)-rich lipoproteins, or the inhibitors of angiopoietin-like 3
(ANGPTL3), which plays a key role in lipid metabolism, aiming to beneficial
effects on TG levels and glucose metabolism. Among others, gene therapy
substituting the loss of essential enzymes is already used for Lipoprotein
Lipase (LPL) deficiency in autosomal chylomicronaemia and is expected to
eliminate the lack of Low- Density Lipoprotein (LDL) receptors in patients with
homozygous familial hypercholesterolaemia. Experimental data of High-Density
Lipoprotein (HDL) mimetics infusion therapy have shown a beneficial effect on
atherosclerotic plaques. Thus, many novel hypolipidaemic drugs targeting
different aspects of lipid metabolism are being investigated, although they need
to be assessed in large trials to prove their CV benefit and safety. Dyslipidemia is one of the most important risk factors for cardiovascular
disease. Insufficient reduction in LDL-C from existing therapies in patients at
high risk of atherogenic cardiovascular disease is an unmet clinical need.
Circulating PCSK9 causes hypercholesterolemia by reducing LDL receptors in
hepatocytes. Areas covered: PCSK9 inhibition has emerged as a promising new
therapeutic strategy to reduce LDL-C. Inclisiran, a novel, synthetic, siRNA
molecule, inhibits PCSK9 synthesis in hepatocytes. Inclisiran targets
intracellular PCSK9 synthesis specifically, resulting in a dose-dependent,
long-term, significant reduction in LDL-C. Inclisiran has been well tolerated
and safe, without severe adverse events so far. This review discusses current
PCSK9 inhibitors and the results of phase I and II clinical trials of
inclisiran. Expert opinion: Plasma PCSK9 enhances the degradation of LDL
receptor, resulting in accumulation of LDL-C in the circulation. Current
approaches with monoclonal antibodies sequester circulating PCSK9 but require
frequent injections. Inclisiran inhibits translation of PCSK9 mRNA and thus
switches off PCSK9 production and provides advantages over monoclonal antibodies
with an infrequent dosing interval of twice a year to reduce LDL-C by over 50%.
Ongoing studies will establish the long-term safety of inclisiran in patients
with high cardiovascular risk and an elevated LDL-C. BACKGROUND: To our knowledge, inclisiran was the first agent composed of small
interfering RNAs (siRNAs) to be preliminarily used to reduce proatherogenic
lipoprotein cholesterol levels. Inclisiran was evaluated in large clinical
trials but did not receive government approval. The ability of inclisiran to
reduce low-density lipoprotein cholesterol (LDL-C) greatly improved its chances
of becoming a novel therapeutic option for patients with hyperlipidemia.
OBJECTIVE: Our goal was to summarize the preliminary effectiveness and safety
data for inclisiran.
METHODS: We conducted a comprehensive search of PubMed, Scopus, Web of Science,
the OVID EMB Reviews database, and Clinical Trials with the keyword "inclisiran"
to find all related randomized controlled trials (RCTs). Five recently published
RCTs involving 583 adults aged 18-65 years with hyperlipidemia were included in
the analysis.
RESULTS: Subgroup analysis suggested that inclisiran 100 mg (standard mean
difference [SMD] - 2.09; 95% confidence interval [CI] - 2.51 to - 1.66;
p < 0.05), 300 mg (SMD - 2.74; 95% CI - 3.61 to - 1.87; p < 0.05), and 500 mg
(SMD - 2.21; 95% CI - 2.62 to - 1.80; p < 0.05) significantly (p < 0.05) reduced
LDL-C and total cholesterol even though pooled analysis showed no LDL-C-lowering
effect (SMD 0.15; 95% CI - 0.34 to 0.04; p = 0.116). Compared with patients
receiving placebo, pooled and subgroup analysis of patients receiving inclisiran
showed no favorable changes in triglycerides or high-density lipoprotein
cholesterol (p > 0.05). The most commonly reported adverse events were
musculoskeletal pain, nasopharyngitis, headache, and elevated C-reactive protein
(CRP), none of which were significant (p > 0.05).
CONCLUSIONS: To date, inclisiran has been effective in treating hyperlipidemia.
Major adverse events were not identified, although other possible adverse events
may be discovered with more RCTs and extensive long-term follow-up. OBJECTIVE: To evaluate the efficacy and safety of inclisiran by diabetes status.
RESEARCH DESIGN AND METHODS: ORION-1 (ClinicalTrials.gov, NCT02597127)
randomized 501 subjects with atherosclerotic cardiovascular disease (ASCVD) or
ASCVD risk equivalents and high LDL cholesterol (LDL-C), despite maximally
tolerated LDL-C-lowering therapies, to one or two doses of placebo or
inclisiran. Levels of lipids and proprotein convertase subtilisin/kexin type 9
(PCSK9) at baseline and day 180 were compared.
RESULTS: Inclisiran was associated with marked declines in LDL-C (median -28% to
-52%, P < 0.0001 and -28% to -55%, P < 0.005 for all doses in the without- and
with-diabetes groups, respectively) and PCSK9. The inclisiran-treated groups
also had lower apolipoprotein B, non-HDL cholesterol, and lipoprotein(a) but
higher HDL cholesterol. Inclisiran had an adverse profile similar to that of
placebo, and adverse events were proportionally balanced in the baseline with-
and without-diabetes groups.
CONCLUSIONS: PCSK9-targeted siRNA-driven strategies may provide a novel
therapeutic option for managing dyslipidemia in the presence and absence of
diabetes. |
Which tool has been developed for visualization of non-covalent contacts? | Visualizations of biomolecular structures empower us to gain insights into biological functions, generate testable hypotheses, and communicate biological concepts. Typical visualizations (such as ball and stick) primarily depict covalent bonds. In contrast, non-covalent contacts between atoms, which govern normal physiology, pathogenesis, and drug action, are seldom visualized. The Protein Contacts Atlas has been developed as an interactive resource of non-covalent contacts from over 100,000 PDB crystal structures. This resource enables researchers from different disciplines to investigate diverse questions in the framework of non-covalent contacts, including the interpretation of allostery, disease mutations and polymorphisms, by exploring individual subunits, interfaces, and protein-ligand contacts and by mapping external information. | |
What is opdivo? | Opdivo or nivolumab is a treatment for patients with unresectable or metastatic melanoma and disease progression following ipilimumab and, if BRAF V600 mutation positive, a BRAF inhibitor. | On December 22, 2014, the FDA granted accelerated approval to nivolumab (OPDIVO;
Bristol-Myers Squibb) for the treatment of patients with unresectable or
metastatic melanoma and disease progression following ipilimumab and, if BRAF
V600 mutation positive, a BRAF inhibitor. Approval was based on a clinically
meaningful, durable objective response rate (ORR) in a non-comparative analysis
of 120 patients who received 3 mg/kg of nivolumab intravenously every 2 weeks
with at least 6-month follow-up in an ongoing, randomized, open-label,
active-controlled clinical trial. The ORR as assessed by a blinded independent
review committee per RECIST v1.1 was 31.7% (95% confidence interval, 23.5-40.8).
Ongoing responses were observed in 87% of responding patients, ranging from 2.6+
to 10+ months. In 13 patients, the response duration was 6 months or longer. The
risks of nivolumab, including clinically significant immune-mediated adverse
reactions (imARs), were assessed in 268 patients who received at least one dose
of nivolumab. The FDA review considered whether the ORR and durations of
responses were reasonably likely to predict clinical benefit, the adequacy of
the safety database, and systematic approaches to the identification,
description, and patient management for imARs in product labeling. Clin Cancer
Res; 23(14); 3484-8. ©2017 AACR. |
Has Hesperidin any role as a Neuroprotective Agent? | Neuroprotective effect of hesperetin and nano-hesperetin on recognition memory impairment and the elevated oxygen stress in rat model of Alzheimer's disease | The present study evaluated antioxidant and neuroprotective activities of
hesperidin, a flavanone mainly isolated from citrus fruits, and its aglycone
hesperetin using cell-free bioassay system and primary cultured rat cortical
cells. Both hesperidin and hesperetin exhibited similar patterns of
1,1-diphenyl-2-picrylhydrazyl radical scavenging activities. While hesperidin
was inactive, hesperetin was found to be a potent antioxidant, inhibiting lipid
peroxidation initiated in rat brain homogenates by Fe2+ and L-ascorbic acid. In
consistence with these findings, hesperetin protected primary cultured cortical
cells against the oxidative neuronal damage induced by H2O2 or xanthine and
xanthine oxidase. In addition, it was shown to attenuate the excitotoxic
neuronal damage induced by excess glutamate in the cortical cultures. When the
excitotoxicity was induced by the glutamate receptor subtype-selective ligands,
only the N-methyl-D-aspartic acid-induced toxicity was selectively and markedly
inhibited by hesperetin. Furthermore, hesperetin protected cultured cells
against the A(beta(25-35))-induced neuronal damage. Hesperidin, however, exerted
minimal or no protective effects on the neuronal damage tested in this study.
Taken together, these results demonstrate potent antioxidant and neuroprotective
effects of hesperetin, implying its potential role in protecting neurons against
various types of insults associated with many neurodegenerative diseases. BACKGROUND: Hesperidin, a flavanone present in citrus fruits, has been
identified as a potent anticancer agent because of its proapoptotic and
antiproliferative characteristics in some tumor cells. However, the precise
mechanisms of action are not entirely understood.
AIM: The main purpose of this study is to investigate the involvement of
peroxisome proliferator-activated receptor-gamma (PPARγ) in hesperidin's
anticancer actions in human pre-B NALM-6 cells, which expresses wild-type p53.
METHODS: The effects of hesperidin on cell-cycle distribution, proliferation,
and caspase-mediated apoptosis were examined in NALM-6 cells in the presence or
absence of GW9662. The expression of peroxisome proliferator-activated
receptor-gamma (PPARγ), p53, phospho-IκB, Bcl-2, Bax, and XIAP proteins were
focused on using the immunoblotting assay. The transcriptional activities of
PPARγ and nuclear factor-kappaB (NF-κB) were analyzed by the transcription
factor assay kits. The expression of PPARγ and p53 was analyzed using the RT-PCR
method.
RESULTS: Hesperidin induced the expression and transcriptional activity of PPARγ
and promoted p53 accumulation and downregulated constitutive NF-κB activity in a
PPARγ-dependent and PPARγ-independent manner. The growth-inhibitory effect of
hesperidin was partially reduced when the cells preincubated with PPARγ
antagonist prior to the exposure to hesperidin.
CONCLUSIONS: The findings of this study clearly demonstrate that
hesperidin-mediated proapoptotic and antiproliferative actions are regulated via
both PPARγ-dependent and PPARγ-independent pathways in NALM-6 cells. These data
provide the first evidence that hesperidin could be developed as an agent
against hematopoietic maligcies. Huntington's disease (HD) is a progressive neurodegenerative disorder with a
spectrum of cognitive, behavioral, and motor abnormalities. The mitochondrial
toxin 3-nitropropionic acid (3-NP) effectively induces specific behavioral
changes, primarily manifested as prepulse inhibition (PPI) deficit of acoustic
startle stimuli, and selective striatal lesions in rats and primates mimicking
those in HD. The implications of nitric oxide in a variety of neurodegenerative
diseases attract attention to study the possible role of flavonoids in
interaction with nitric oxide pathways involved in HD. The present study
investigates the potential effect of hesperidin, a flavanone group member, on
3-NP-induced behavioral, neurochemical, histopathological and cellular changes.
Systemic administration of 3-NP to rats for 5 days (20 mg/kg) caused reduction
of locomotor activity by days 2 and 5, 55% deficit of PPI response, elevation of
cortical, striatal and hippocampal malondialdehyde (MDA) levels by 63%, 41% and
56%, reduction of respective catalase activity by 50%. Immunohistochemical
staining of cortices, striata and hippocampi showed patches of iNOS positive
cells. Electron microscopic ultrastructural examination showed marked
mitochondrial swelling, perivascular edema and shrunken nerve cells.
Pretreatment with hesperidin (100 mg/kg) ahead of 3-NP prevented any changes of
locomotor activity or PPI response, slightly increased cortical, striatal and
hippocampal MDA levels by 10% and reduced respective catalase activity by 22%,
20% and 5%. Only few iNOS positive cells were detected in sections from rats
pretreated with hesperidin which also reduced cellular abnormalities induced by
3-NP. This study suggests a potential neuroprotective role of hesperidin against
3-NP-induced Huntington's disease-like manifestations. Such neuroprotection can
be referred to its antioxidant and anti-inflammatory activities. Rotenone a widely used pesticide that inhibits mitochondrial complex I has been
used to investigate the pathobiology of PD both in vitro and in vivo. Studies
have shown that the neurotoxicity of rotenone may be related to its ability to
generate reactive oxygen species (ROS), leading to neuronal apoptosis. The
current study was carried out to investigate the neuroprotective effects of
hesperidin, a citrus fruit flavanol, against rotenone-induced apoptosis in human
neuroblastoma SK-N-SH cells. We assessed cell death, mitochondrial membrane
potential, ROS generation, ATP levels, thiobarbituric acid reactive substances,
reduced glutathione (GSH) levels, and the activity of catalase, superoxide
dismutase (SOD) and glutathione peroxidase (GPx) using well established assays.
Apoptosis was determined in normal, rotenone, and hesperidin treated cells, by
measuring the protein expression of cytochrome c (cyt c), caspases 3 and 9, Bax,
and Bcl-2 using the standard western blotting technique. The apoptosis in
rotenone-induced SK-N-SH cells was accompanied by the loss of mitochondrial
membrane potential, increased ROS generation, the depletion of GSH, enhanced
activities of enzymatic antioxidants, upregulation of Bax, cyt c, and caspases 3
and 9, and downregulation of Bcl-2, which were attenuated in the presence of
hesperidin. Our data suggests that hesperidin exerts its neuroprotective effect
against rotenone due to its antioxidant, maintece of mitochondrial function,
and antiapoptotic properties in a neuroblastoma cell line. AIM: Epilepsy is a chronic neurological disorder with complex pathophysiology.
Several evidences suggest a role of oxidative stress and mitochondrial
dysfunction in pathophysiology of epilepsy. Hesperidin (Hesp) acts as a powerful
anti-oxidant agent against superoxide, singlet oxygen, and hydroxyl radicals.
Thus, this study was undertaken to evaluate the possible neuroprotective
mechanism of Hesp against pentylenetetrazole (PTZ)-induced convulsions in mice.
MATERIALS AND METHODS: Sixty males Laca mice (20-25 g) were randomly divided
into 10 treatment groups (n = 6). Seven days pretreatment of Hesp (100, 200
mg/kg, p.o.) was carried out before PTZ (80 mg/kg, intraperitoneal [i.p.])
challenge, whereas diazepam (DZP) (0.2, 0.5 mg/kg) and gabapentin (Gbp) (10, 20
mg/kg) were administered i.p. 30 min before PTZ administration, that is, on
7(th) day. Following PTZ challenge, severity of convulsions (onset of jerks,
myoclonic seizures, extensor phase and death), brain anti-oxidant enzyme levels
and mitochondrial complex enzymes activities were estimated.
RESULTS: Single i.p. PTZ (80 mg/kg) challenge demonstrated severe convulsions,
oxidative damage (raised lipid peroxidation [LPO], nitrite concentration as well
as depleted reduced glutathione, superoxide dismutase and catalase levels), and
depletion of mitochondrial enzyme Complex (I, II, IV) activities. Hesp (200
mg/kg), DZP (0.5 mg/kg) and Gbp (20 mg/kg) pretreatments attenuated PTZ induced
behavioral, biochemical and mitochondrial alterations. However, administration
of Hesp (100 mg/kg) in combination with DZP (0.2 mg/kg) or Gbp (10 mg/kg)
potentiated their neuroprotective effect, which was significant as compared to
their effects in PTZ treated animals.
CONCLUSION: Hesp possesses potent anticonvulsant activity which might be
mediated through modulation of gamma-amino butyric acid/benzodiazepine receptor
action. PURPOSE: Hesperidin, a glycoside flavonoid, is thought to act as an anti-cancer
agent, since it has been found to exhibit both pro-apoptotic and
anti-proliferative effects in several cancer cell types. The mechanisms
underlying hesperidin-induced growth arrest and apoptosis are, however, not well
understood. Here, we aimed to investigate the anti-proliferative and apoptotic
effects of hesperidin on non-small cell lung cancer (NSCLC) cells and to
investigate the mechanisms involved.
METHODS: The anti-proliferative and apoptotic effects of hesperidin on two
NSCLC-derived cell lines, A549 and NCI-H358, were determined using a WST-1
colorimetric assay, a LDH cytotoxicity assay, a Cell Death Detection assay, an
AnnexinV-FITC assay, a caspase-3 assay and a JC-1 assay, respectively, all in a
time- and dose-dependent manner. As a control, non-cancerous MRC-5 lung
fibroblasts were included. Changes in whole genome gene expression profiles were
assessed using an Illumina Human HT-12v4 beadchip microarray platform, and
subsequent data analyses were performed using an Illumina Genome Studio and
Ingenuity Pathway Analyser (IPA).
RESULTS: We found that after hesperidin treatment, A549 and NCI-H358 cells
exhibited decreasing cell proliferation and increasing caspase-3 and other
apoptosis-related activities, in conjunction with decreasing mitochondrial
membrane potential activities, in a dose- and time-dependent manner. Through a
GO analysis, by which changes in gene expression profiles were compared, we
found that the FGF and NF-κB signal transduction pathways were most
significantly affected in the hesperidin treated NCI-H358 and A549 NSCLC cells.
CONCLUSIONS: Our results indicate that hesperidin elicits an in vitro growth
inhibitory effect on NSCLC cells by modulating immune response-related pathways
that affect apoptosis. When confirmed in vivo, hesperidin may serve as a novel
anti-proliferative agent for non-small cell lung cancer. Cancer is the third cause of death worldwide, with complex etiology, and is
defined as an uncontrolled growth of cells. A high proportion of cancer
incidence and deaths are due to different environmental and genetic factors such
as high body mass index, low fruit and vegetable intake, lack of physical
activity, tobacco use, alcohol consumption, exposure to radiation, chronic
infections, and heredity also. In addition, oxidative stress plays a crucial
role in the pathophysiology of different types of cancer. Hence, screening and
testing of more effective compounds with minimum side effects for the prevention
and treatment of cancers started a few decades ago. Regarding this, much
attention has been paid to natural antioxidants as a novel prevention and
treatment strategy for cancer. Flavonoids are one of the most important
ingredients in vegetables and fruits, especially in the genus Citrus. Hesperidin
is a flavonone glycoside, belonging to the flavonoid family, which is widely
found in Citrus species and acts as a potent antioxidant and anticancer agent.
In the present review, we attempt to provide an overview and summarize the
scientific literature about the cancer chemoprotective effects of hesperidin
with an emphasis on its relation to the protection roles against oxidative
stress. BACKGROUND: The benefits of the Mediterranean diet for protecting against many
diseases are usually attributed to high consumption of certain foods,
characterized by the presence of bioactive substances such as polyphenols.
Inflammation plays an important role in the pathogenesis of numerous diseases
such as arthritis, allergies or neurodegenerative disorders. Dietary polyphenols
constitute a large family of bioactive substances with potential beneficial
effects against a broad group of diseases. Citrus fruits and juices are a rich
source of vitamin C and flavonoids, with a potential effect on the inflammatory
response.
OBJECTIVE: The aim was to evidence the potential anti-inflammatory effects of
the flavonoids hesperidin for its possible therapeutic application against
diverse pathologies.
METHOD: In the present review, available literature about the anti-inflammatory
effects of hesperidin is reported and discussed. Moreover, we also discuss the
chemistry, bioavailability and proposed mechanisms of action of hesperidin.
RESULTS: Hesperidin is a flavonoid present in high concentration in citrus
species and has numerous biological properties, principally antioxidant and
anti-inflammatory. Several studies have been performed in order to evaluate the
effects of hesperidin as anti-inflammatory agent using cellular and animal
models and few clinical trials. Hesperidin treatment decreased inflammatory
mediators and exerted significant antioxidant effects. The molecular basis for
its anti-inflammatory effects seems to be mediated by signalling pathways
especially the nuclear factor κβ pathway.
CONCLUSION: Although hesperidin evidenced anti-inflammatory effects, the
specific mechanism of action is not completely known and additional studies are
required for elucidation of the molecular targets. We found that hesperidin, a plant-derived bioflavonoid, may be a candidate agent
for neuroprotective treatment in the retina, after screening 41 materials for
anti-oxidative properties in a primary retinal cell culture under oxidative
stress. We found that the intravitreal injection of hesperidin in mice prevented
reductions in markers of the retinal ganglion cells (RGCs) and RGC death after
N-methyl-D-aspartate (NMDA)-induced excitotoxicity. Hesperidin treatment also
reduced calpain activation, reactive oxygen species generation and TNF-α gene
expression. Finally, hesperidin treatment improved electrophysiological
function, measured with visual evoked potential, and visual function, measured
with optomotry. Thus, we found that hesperidin suppressed a number of cytotoxic
factors associated with NMDA-induced cell death signaling, such as oxidative
stress, over-activation of calpain, and inflammation, thereby protecting the
RGCs in mice. Therefore, hesperidin may have potential as a therapeutic
supplement for protecting the retina against the damage associated with
excitotoxic injury, such as occurs in glaucoma and diabetic retinopathy. Alzheimer disease (AD) is a progressive dementia affecting a large proportion of
the aging population. There is evidence that brain tissue in patients with AD is
exposed to oxidative stress during the course of the disease. Hesperetin (Hst)
is a natural flavonoid, which has been reported to exert various biological
activities such as antioxidant and anti-inflammatory effect. The present study
aimed to investigate the effects of hesperetin and o-hesperetin on
neurobehavioral activity and superoxide dismutase (SOD), glutathione peroxidase
(GPx), glutathione reductase (GRx) and catalase (CAT) enzymes activity,
malondialdehyde (MDA) and glutathione (GSH) levels in hippocampal area of rats
in an experimental model of AD. The AD was induced in animals by
intracerebroventricular injection of STZ (icv-STZ) unilaterally. Animals were
treated with the Hst and o-Hst (10, 20 mg/kg body weight), then after three
successive weeks, recognition memory was examined (passive avoidance test and
novel object recognition test) and antioxidant parameters were evaluated. In our
study behavioral testes showed improvement on memory retrieval and recognition
memory consolidation. Furthermore the Hst and o-Hst increased the activity of
antioxidant enzymes (SOD, glutathione GPx, GRx and CAT) and GSH levels and
decreased MDA in the hippocampal area. These results suggested that Hst and
o-Hst may inhibit STZ-induced oxidative stress, and that it may possess
therapeutic potential for the treatment of AD. Hesperidin, a flavanoglycone abundantly present in citrus fruits, is reported to
have antioxidant, anti-inflammatory, and neuroprotective properties. Previous
reports from our laboratory indicated the neuroprotective effect of hesperidin
against aluminum chloride (AlCl3)-induced memory loss, acetylcholine esterase
hyperactivity, oxidative stress, and enhanced expression of amyloid β protein
biosynthesis-related markers. However, their role on AlCl3-induced inflammation,
caspase activation, Tau pathology, altered Akt/GSK 3β signaling pathway, and Aβ
clearance marker has not yet been fully elucidated. Intraperitonial injection of
AlCl3 (100 mg/kg body weight) for 60 days significantly elevated the expressions
of insulin-degrading enzyme (IDE), cyclin-dependent kinase 5 (CDK 5), and
phosphoTau (pTau); inflammatory markers such as glial fibrillary acidic protein
(GFAP), ionized calcium-binding adapter molecule 1 (Iba-1), NF-kB,
cyclooxygenase-2 (COX-2), interleukin (IL)-1β, IL-4, IL-6, tumor necrosis
factor-alpha (TNF-α), inducible nitric oxide synthase (iNOS); and apoptotic
markers including cytosolic cytochrome c (cyto c), caspase-3, caspase-8, and
caspase-9, and lowered expressions of mitochondrial cyto c, phospho-Akt (pAkt)
and phospho-glycogen synthase kinase-3β (pGSK-3β) in the hippocampus and cortex.
Co-administration of hesperidin to AlCl3 rats for 60 days significantly
ameliorated the aluminum-induced pathological changes. The behavioral studies
also supported the above findings. Our results imply that treatment with
hesperidin might be a potent option for treating the symptoms of cognitive
impairment in Alzheimer's disease by targeting its most prominent hallmarks. AIMS: There is increasing evidence showing that mild traumatic brain injury
(mTBI) is associated with increased depression-related disorders in humans.
Recent studies suggest that dietary intake or supplementation of natural
flavonoids like hesperidin can be used for therapy of patients with brain injury
and depression. However, the exact mechanisms by which hesperidin indicates its
neuroprotective effects are not fully understood. The purpose of this study was
to explore the influence of hesperidin on depression-related symptoms in a mouse
model of mTBI, and that what mechanisms are primarily involved in the
antidepressant effects of this bioflavonoid.
MAIN METHODS: Ten days after mTBI-induction, mice received oral hesperidin
treatment (50 mg/kg/14 days), then animals were subjected to different
depression tests including sucrose preference test, forced swim test,
novelty-suppressed feeding test, and tail suspension test. We also measured
levels of tumor necrosis factor (TNF)-α, interleukin-(IL)-1β, malondialdehyde
(MDA), and brain-derived-neurotrophic-factor (BDNF) in the hippocampus.
KEY FINDINGS: Our results show that mTBI induction induced depressive-like
behaviors in mice by increasing inflammatory cytokines (IL-1β and TNF-α) and
oxidative stress marker (MDA), and reducing BDNF levels in the hippocampus.
Interestingly, hesperidin treatment was effective to significantly reduce
depression-related symptoms in mTBI-induced mice. In addition, hesperidin
decreased the levels of IL-1β, TNF-α and MDA, and increased BDNF levels in the
hippocampus. The major strength of our study is that four behavioral tests gave
similar results.
SIGNIFICANCE: This study suggests that the antidepressant-like effect of
hesperidin may be mediated, at least in part, by decreased neuroinflammation and
oxidative damage, and enhanced BDNF production in the hippocampus. OBJECTIVE: We examined the protective effects of hesperidin on cerebral
vasospasm by establishing an experimental rat model of subarachnoid hemorrhage
and performing biochemical, pathologic, and histomorphometric analysis on these
data.
METHODS: Forty albino Wistar rats were randomly divided into 5 groups of n = 8
in each: group (G)1, no experimental interventions; G2, subjected to
subarachnoid hemorrhage; G3, subjected to subarachnoid hemorrhage and
administered saline (100 mg/kg); G4, subjected to subarachnoid hemorrhage and
treated with low-dose hesperidin (50 mg/kg); and G5, subjected to subarachnoid
hemorrhage and treated with high-dose hesperidin (100 mg/kg). Subarachnoid
hemorrhage was created by injecting 0.15 cc of autologous blood taken from the
rat-tail artery and injected into the cisterna magna from the craniocervical
junction. Drugs were administered intraperitoneally as twice daily doses for 48
hours. Rats were euthanized at the end of this period.
RESULTS: No statistically significant decrease was observed in malondialdehyde
levels, which is the end-product of lipid peroxidation, among the drug groups
(G4 and G5). Thin sections prepared from the basilar artery were examined
morphologically. Severe luminal narrowing and vessel-wall thickening were
observed in the subarachnoid hemorrhage groups (G2, G3). In the
hesperidin-administered groups (G4, G5), it was determined that vessel wall
thickness measurements revealed thinner walls than in the subarachnoid
hemorrhage groups (G2, G3) and the luminal diameters were significantly larger
than in the subarachnoid hemorrhage groups (G2, G3).
CONCLUSIONS: These findings suggest that hesperidin has no effect on
malondialdehyde-associated lipid-peroxidation activity; however, it might be
useful in subarachnoid hemorrhage therapy because of its beneficial effects on
vessel wall thickness and luminal diameters. |
Are apoE mimetics being considered as a treatment against Alzheimer's disease? | Yes, apoE mimetics are being considered as a treatment against Alzheimer's disease, and they have been shown to protect AD mouse models against these AD-like features. | BACKGROUND: Amyloid-β (Aβ) peptides derive from the amyloid precursor protein
(APP) and play a pivotal role in Alzheimer's disease (AD) pathogenesis. Our
previous work showed that the APP intracellular domain (AICD), which is produced
simultaneously with Aβ, also contributes to the development of AD-like features.
Studies show that administration of apolipoprotein E (apoE) and apoE-derived
small peptide mimetics protect AD mouse models against these AD-like features.
However, the effects of apoE-mimetic treatment on AICD-mediated AD-like
pathologies remain to be elucidated.
OBJECTIVE: To study the effects of an apoE mimetic (COG112) on
neuroinflammation, hyperphosphorylation of tau and defects in adult neurogenesis
in AICD- overexpressing transgenic mice (FeCγ25 line).
METHODS: Beginning at 1 month of age, animals were administered subcutaneous
COG112 3 times per week for 3 months, followed by immunohistochemical analysis
for neuroinflammation, neurogenesis and phosphorylated tau.
RESULTS: Treatment with COG112 significantly reduced neuroinflammation in AICD
mice and protected against impaired adult hippocampal neurogenesis. We also
found that COG112 treatment reduced hyperphosphorylation and somatodendritic
accumulation of tau in the hippocampus and cerebral cortex of AICD mice.
CONCLUSIONS: Reduction of neuroinflammation by the apoE-mimetic COG112 protects
against impaired neurogenesis and tau pathology in AICD transgenic mice. These
data suggest that neuroinflammation plays an important role in AICD-induced
AD-like pathologies. |
Which diseases are treated with netarsudil? | In 2 large, randomized, double-masked trials, once-daily dosing of netarsudil 0.02% was found to be effective and well tolerated for the treatment of patients with ocular hypertension and open-angle glaucoma. | Inhibition of Rho kinase (ROCK) to improve fluid outflow through the trabecular
meshwork and lower intraocular pressure is a strategy for the development of new
anti-glaucoma agents. Alpha-aryl-beta-amino isoquinoline analogs were identified
as potent ROCK inhibitors. Compounds that provided a longer duration of
intraocular pressure reduction in Dutch Belted rabbits also inhibited
norepinephrine transporter. Ester 60 improved bioavailability of its parent ROCK
inhibitor, 29 (Ki=0.2nM) and demonstrated an effective and sustained IOP
reduction for 24h after dosing. From these studies, netarsudil (a.k.a. AR-13324)
was discovered and is currently in clinical trials for the treatment of glaucoma
and ocular hypertension. PURPOSE: Rho-associated protein kinase (ROCK) inhibitors lower intraocular
pressure (IOP) by increasing aqueous outflow through the trabecular meshwork
(TM). The preclinical characterization of netarsudil, a new ROCK/norepinephrine
transporter (NET) inhibitor currently in clinical development, is presented
herein.
METHODS: The kinase inhibitory activity of netarsudil was compared to its
esterase metabolite, netarsudil-M1, and 3 other ROCK inhibitors using a
commercially available kinase assay kit. Disruption of actin stress fibers was
measured in primary porcine TM cells and disruption of focal adhesions in
transformed human TM (HTM) cells. Induction of fibrosis markers after exposure
to transforming growth factor-β2 (TGF-β2) was conducted in primary HTM cells.
Ocular hypotensive activity and tolerability of topical formulations were
evaluated in normotensive Dutch Belted rabbits and Formosan Rock monkeys. In
vitro corneal metabolism assays were conducted using dog, pig, rabbit, monkey,
and human corneas. In vivo ocular pharmacokinetics was studied in Dutch Belted
rabbits.
RESULTS: Netarsudil inhibited kinases ROCK1 and ROCK2 with a Ki of 1 nM each,
disrupted actin stress fibers and focal adhesions in TM cells with IC50s of 79
and 16 nM, respectively, and blocked the profibrotic effects of TGF-β2 in HTM
cells. Netarsudil produced large reductions in IOP in rabbits and monkeys that
were sustained for at least 24 h after once daily dosing, with transient, mild
hyperemia observed as the only adverse effect.
CONCLUSION: Netarsudil is a novel ROCK/NET inhibitor with high potency in
biochemical and cell-based assays, an ability to produce large and durable IOP
reductions in animal models, and favorable pharmacokinetic and ocular
tolerability profiles. Netarsudil ophthalmic solution (Rhopressa) for the reduction of elevated
intraocular pressure; ertugliflozin (Steglatro) for adults with type-2 diabetes;
and lutetium lu 177 dotatate (Lutathera) for certain gastroenteropancreatic
neuroendocrine tumors. Peripheral vision loss followed by "tunnel vision" and eventual irreversible
blindness is the fate of patients afflicted by various forms of glaucoma
including primary open-angle glaucoma (POAG) and normotensive glaucoma (NTG).
These complex and heterogeneous diseases are characterized by extensive death of
retinal ganglion cells (RGCs) accompanied by retraction and severance of their
axonal connections to the brain and thus damage to and thinning of the optic
nerve. Since patients suffering from this glaucomatous optic neuropathy (GON)
first notice visual impairment when they have lost > 40% of their RGCs, early
diagnosis is the key to retard the progression of glaucoma. Elevated intraocular
pressure (IOP), low cerebrospinal and/or low intracranial fluid pressure,
advancing age, and ethnicity are major risk factors associated with POAG.
However, retinal vascular abnormalities and a high sensitivity of RGCs and optic
nerve head components to neurotoxic, inflammatory, oxidative and mechanical
insults also contribute to vision loss in POAG/GON. Current treatment modalities
for POAG and NTG involve lowering IOP using topical ocular drugs, combination
drug products, and surgical interventions. Two recently approved
multi-pharmacophoric drugs (e.g., rho kinase inhibitor, Netarsudil; a drug
conjugate, Latanoprostene Bunod) and novel aqueous humor drainage devices
(iStent and CyPass) are also gaining acceptance for treating POAG/ NTG.
Neuroprotective and regenerative agents, coupled with electroceutical,
mechanical support systems, stem cell transplantation and gene therapy are
emerging therapeutics on the horizon to help combat GON. The latter techniques
and approaches hope to rejuvenate RGCs and repair the optic nerve structures,
thereby providing a gain of function of the visual system for the glaucoma
patients. Once-daily (p.m.) netarsudil ophthalmic solution 0.02% (Rhopressa) is approved
in the United States for lowering elevated intraocular pressure (IOP) in
patients with open-angle glaucoma or ocular hypertension. Netarsudil, a Rho
kinase (ROCK) inhibitor that lowers IOP primarily by increasing trabecular
outflow, produces statistically and clinically significant reductions in mean
IOP from baseline, with comparable effects on nocturnal and diurnal IOP. In
three phase III trials of patients with elevated IOP, the ocular hypotensive
efficacy of once-daily netarsudil 0.02% met the criteria for noninferiority to
twice-daily timolol 0.5% at all time points over 3 months in patients with
baseline IOP less than 25 mmHg. The most frequent adverse event (AE) was
generally mild conjunctival hyperemia, the severity of which did not increase
with continued dosing. Netarsudil was associated with minimal treatment-related
serious or systemic AEs, likely due to the lack of systemic exposure. This
report summarizes the available preclinical and clinical data on netarsudil. Netarsudil ophthalmic solution is a novel topical intraocular pressure
(IOP)-lowering agent that has recently been approved by the US Food and Drug
Administration (FDA) for the treatment of ocular hypertension and open-angle
glaucoma. Its unique pharmacology allows for IOP lowering as a result of direct
reduction in trabecular outflow resistance in addition to a decrease in
episcleral venous pressure and aqueous humor production. The efficacy of
netarsudil has been shown in animal studies and human clinical trials. It has
been shown to be noninferior to the therapy with topical timolol in individuals
with baseline IOP <25 mmHg. Importantly, netarsudil has been shown to reduce IOP
to the same degree, regardless of baseline levels. There are no known systemic
safety issues associated with netarsudil. The most common local adverse effects
relate to conjunctival hyperemia. The once-daily dosing schedule is advantageous
for individuals who have difficulties with medication adherence. Further studies
of a combination of netarsudil and latanoprost agents are currently underway. |
Can you computationally predict Molecular Recognition Features (MoRFs) regions in Intrinsically Disordered Proteins (IDPs)? | Yes. There are various tools available in the literature that enable computational identification of Molecular Recognition Features (MoRFs) regions in intrinsically disordered protein sequences. | MOTIVATION: Intrinsically disordered regions of proteins play an essential role
in the regulation of various biological processes. Key to their regulatory
function is the binding of molecular recognition features (MoRFs) to globular
protein domains in a process known as a disorder-to-order transition. Predicting
the location of MoRFs in protein sequences with high accuracy remains an
important computational challenge.
METHOD: In this study, we introduce MoRFCHiBi, a new computational approach for
fast and accurate prediction of MoRFs in protein sequences. MoRFCHiBi combines
the outcomes of two support vector machine (SVM) models that take advantage of
two different kernels with high noise tolerance. The first, SVMS, is designed to
extract maximal information from the general contrast in amino acid compositions
between MoRFs, their surrounding regions (Flanks), and the remainders of the
sequences. The second, SVMT, is used to identify similarities between regions in
a query sequence and MoRFs of the training set.
RESULTS: We evaluated the performance of our predictor by comparing its results
with those of two currently available MoRF predictors, MoRFpred and ANCHOR.
Using three test sets that have previously been collected and used to evaluate
MoRFpred and ANCHOR, we demonstrate that MoRFCHiBi outperforms the other
predictors with respect to different evaluation metrics. In addition, MoRFCHiBi
is downloadable and fast, which makes it useful as a component in other
computational prediction tools.
AVAILABILITY AND IMPLEMENTATION: http://www.chibi.ubc.ca/morf/. MOTIVATION: Intrinsically disordered regions of proteins play an essential role
in the regulation of various biological processes. Key to their regulatory
function is often the binding to globular protein domains via sequence elements
known as molecular recognition features (MoRFs). Development of computational
tools for the identification of candidate MoRF locations in amino acid sequences
is an important task and an area of growing interest. Given the relative
sparseness of MoRFs in protein sequences, the accuracy of the available MoRF
predictors is often inadequate for practical usage, which leaves a significant
need and room for improvement. In this work, we introduce MoRFCHiBi_Web, which
predicts MoRF locations in protein sequences with higher accuracy compared to
current MoRF predictors.
METHODS: Three distinct and largely independent property scores are computed
with component predictors and then combined to generate the final MoRF
propensity scores. The first score reflects the likelihood of sequence windows
to harbour MoRFs and is based on amino acid composition and sequence similarity
information. It is generated by MoRFCHiBi using small windows of up to 40
residues in size. The second score identifies long stretches of protein disorder
and is generated by ESpritz with the DisProt option. Lastly, the third score
reflects residue conservation and is assembled from PSSM files generated by
PSI-BLAST. These propensity scores are processed and then hierarchically
combined using Bayes rule to generate the final MoRFCHiBi_Web predictions.
RESULTS: MoRFCHiBi_Web was tested on three datasets. Results show that
MoRFCHiBi_Web outperforms previously developed predictors by generating less
than half the false positive rate for the same true positive rate at practical
threshold values. This level of accuracy paired with its relatively high
processing speed makes MoRFCHiBi_Web a practical tool for MoRF prediction.
AVAILABILITY: http://morf.chibi.ubc.ca:8080/morf/. MOTIVATION: Intrinsically Disordered Proteins (IDPs) lack stable tertiary
structure and they actively participate in performing various biological
functions. These IDPs expose short binding regions called Molecular Recognition
Features (MoRFs) that permit interaction with structured protein regions. Upon
interaction they undergo a disorder-to-order transition as a result of which
their functionality arises. Predicting these MoRFs in disordered protein
sequences is a challenging task.
METHOD: In this study, we present MoRFpred-plus, an improved predictor over our
previous proposed predictor to identify MoRFs in disordered protein sequences.
Two separate independent propensity scores are computed via incorporating
physicochemical properties and HMM profiles, these scores are combined to
predict final MoRF propensity score for a given residue. The first score
reflects the characteristics of a query residue to be part of MoRF region based
on the composition and similarity of assumed MoRF and flank regions. The second
score reflects the characteristics of a query residue to be part of MoRF region
based on the properties of flanks associated around the given residue in the
query protein sequence. The propensity scores are processed and common averaging
is applied to generate the final prediction score of MoRFpred-plus.
RESULTS: Performance of the proposed predictor is compared with available MoRF
predictors, MoRFchibi, MoRFpred, and ANCHOR. Using previously collected training
and test sets used to evaluate the mentioned predictors, the proposed predictor
outperforms these predictors and generates lower false positive rate. In
addition, MoRFpred-plus is a downloadable predictor, which makes it useful as it
can be used as input to other computational tools.
AVAILABILITY:
https://github.com/roneshsharma/MoRFpred-plus/wiki/MoRFpred-plus:-Download. MOTIVATION: Intrinsically disordered proteins lack stable 3-dimensional
structure and play a crucial role in performing various biological functions.
Key to their biological function are the molecular recognition features (MoRFs)
located within long disordered regions. Computationally identifying these MoRFs
from disordered protein sequences is a challenging task. In this study, we
present a new MoRF predictor, OPAL, to identify MoRFs in disordered protein
sequences. OPAL utilizes two independent sources of information computed using
different component predictors. The scores are processed and combined using
common averaging method. The first score is computed using a component MoRF
predictor which utilizes composition and sequence similarity of MoRF and
non-MoRF regions to detect MoRFs. The second score is calculated using
half-sphere exposure (HSE), solvent accessible surface area (ASA) and backbone
angle information of the disordered protein sequence, using information from the
amino acid properties of flanks surrounding the MoRFs to distinguish MoRF and
non-MoRF residues.
RESULTS: OPAL is evaluated using test sets that were previously used to evaluate
MoRF predictors, MoRFpred, MoRFchibi and MoRFchibi-web. The results demonstrate
that OPAL outperforms all the available MoRF predictors and is the most accurate
predictor available for MoRF prediction. It is available at
http://www.alok-ai-lab.com/tools/opal/.
CONTACT: [email protected] or [email protected].
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. Intrinsically disordered proteins and regions are involved in a wide range of
cellular functions, and they often facilitate protein-protein interactions.
Molecular recognition features (MoRFs) are segments of intrinsically disordered
regions that bind to partner proteins, where binding is concomitant with a
transition to a structured conformation. MoRFs facilitate translation,
transport, signaling, and regulatory processes and are found across all domains
of life. A popular computational tool, MoRFpred, accurately predicts MoRFs in
protein sequences. MoRFpred is implemented as a user-friendly web server that is
freely available at http://biomine.cs.vcu.edu/servers/MoRFpred/ . We describe
this predictor, explain how to run the web server, and show how to interpret the
results it generates. We also demonstrate the utility of this web server based
on two case studies, focusing on the relevance of evolutionary conservation of
MoRF regions. Intrinsically disordered proteins (IDPs) contain long unstructured regions,
which play an important role in their function. These intrinsically disordered
regions (IDRs) participate in binding events through regions called molecular
recognition features (MoRFs). Computational prediction of MoRFs helps identify
the potentially functional regions in IDRs. In this study, OPAL+, a novel MoRF
predictor, is presented. OPAL+ uses separate models to predict MoRFs of varying
lengths along with incorporating the hidden Markov model (HMM) profiles and
physicochemical properties of MoRFs and their flanking regions. Together, these
features help OPAL+ achieve a marginal performance improvement of 0.4-0.7% over
its predecessor for diverse MoRF test sets. This performance improvement comes
at the expense of increased run time as a result of the requirement of HMM
profiles. OPAL+ is available for download at
https://github.com/roneshsharma/OPAL-plus/wiki/OPAL-plus-Download. |
Which malignancies is Keytruda approved for before 2017? | Before 2017 Keytruda was approved for the treatment of several types of malignancies, such as metastatic melanoma, metastatic non-small-cell lung cancer, recurrent or metastatic head and neck cancer, refractory Hodgkin lymphoma, and urothelial carcinoma. | |
Which was the first approved tumor treatment using a common biomarker rather than specified tumor locations in the body? | The first approved tumor treatment using a common biomarker rather than specified tumor locations in the body was Keytruda, which is a treatment for cancer patients with positive microsatellite instability-high (MSI-H) markers or mismatch repair deficient (dMMR) markers. | |
What does Prevnar 13 consist of? | Prevnar 13 consists of 13 serotype-specific polysaccharides of Streptococcus pneumoniae (pneumococcus), each covalently conjugated to a non-toxic immunogenic carrier protein. | The 13-valent pneumococcal conjugate vaccine (Prevenar 13(®), Prevnar 13(®))
[PCV13] consists of 13 serotype-specific polysaccharides of Streptococcus
pneumoniae (pneumococcus), each covalently conjugated to a non-toxic immunogenic
carrier protein. PCV13 has a well established immunogenicity and tolerability
profile in adults, particularly those ≥50 years of age. Results of CAPiTA, a
randomized, double-blind, placebo-controlled trial in >84,000 older adults aged
≥65 years, showed that PCV13 was effective in preventing vaccine-type
pneumococcal community-acquired pneumonia (CAP), vaccine-type pneumococcal
nonbacteraemic (noninvasive) CAP and vaccine-type invasive pneumococcal disease
(IPD). These findings, along with changes in pneumococcal serotype distribution
and epidemiology of pneumococcal disease, prompted the US Advisory Committee on
Immunization Practices (ACIP) to recommend PCV13 in series with 23-valent
pneumococcal polysaccharide vaccine (PPVS23) for all adults aged ≥65 years.
PCV13 also has a role in preventing pneumococcal disease (pneumonia and IPD) in
younger adults with immunocompromising conditions and potentially in those with
other underlying medical conditions that increase the risk of pneumococcal
disease. |
What is the route of administration of apixaban? | Apixaban is administered orally. | |
What is the cause of a STAG3 truncating variant? | Linkage analysis identified a locus on chromosome 7 where exome sequencing successfully identified a homozygous two base pair duplication (c.1947_48dupCT), leading to a truncated protein p.(Y650Sfs*22) in the STAG3 gene, confirming it as the cause of POI in this family | STUDY QUESTION: Does a novel homozygous NOBOX truncating variant, identified in
whole exome sequencing (WES) of patients with primary ovarian insufficiency
(POI), cause defective transcriptional activation of multiple oocyte-related
genes?
SUMMARY ANSWER: A novel homozygous truncating mutation of NOBOX was confirmed to
exhibit a loss-of-function effect using well-defined molecular and functional
analyses.
WHAT IS KNOWN ALREADY: Several NOBOX mutations have been reported to be
associated with POI but all of them are heterozygous mutations.
STUDY DESIGN, SIZE, DURATION: This is a cross sectional study in 96 patients
diagnosed with POI and 211 women not diagnosed with POI in China.
PARTICIPANTS/MATERIALS, SETTING, METHODS: Blood samples collected from the
participants were subjected to whole exome sequencing. Full-length transcript of
NOBOX was cloned directly from human fetal ovary (FO). Functional analysis was
performed for a NOBOX sequence variant associated with POI.
MAIN RESULTS AND THE ROLE OF CHANCE: One novel homozygous truncating variant,
chr7:144098161delC, in the NOBOX gene was found in a POI patient. The truncating
variant showed a severe defect in transcriptional activation of GDF9 a
well-known target NOBOX. Furthermore, using real-time quantitative PCR analysis,
we found many oocyte-related genes were expressed at lower level in truncating
variant cells than in control cells. In addition, we found that the truncated
NOBOX lost its ability to induce the G2/M arrest.Notably, our results confirmed
that the 1725 bp NOBOX transcript is expressed in human FO and is the only
functional isoform in transcriptional activation assays.
LIMITATIONS REASONS FOR CAUTION: Although the in vitro assays demonstrated the
loss-of-function effect of truncating mutation on NOBOX transcriptional
activation, further studies are needed to validate its long-term effects on
folliculogenesis and POI.
WIDER IMPLICATIONS OF THE FINDINGS: This is the first homozygous mutation of
NOBOX associated with POI showing a loss-of-function effect using well-defined
molecular and functional analyses. These results will aid both researchers and
clinicians in understanding the molecular pathology of NOBOX and POI to develop
diagnostic assays or therapeutic approaches.
STUDY FUNDING/COMPETING INTERESTS: Research funding is provided by the Ministry
of Science and Technology of China [2012CB944704; 2012CB966702], the National
Natural Science Foundation of China [Grant number: 31171429] and Beijing
Advanced Innovation Center for Structural Biology. The authors declare no
conflict of interest. |
Which tools have been developed for computing split-networks? | Split-networks are a generalization of phylogenetic trees that have proven to be a powerful tool in phylogenetics. Tools for computing such networks include SPECTRE, FlatNJ and QNet. | We present QNet, a method for constructing split networks from weighted quartet
trees. QNet can be viewed as a quartet analogue of the distance-based
Neighbor-Net (NNet) method for network construction. Just as NNet, QNet works by
agglomeratively computing a collection of circular weighted splits of the taxa
set which is subsequently represented by a planar split network. To illustrate
the applicability of QNet, we apply it to a previously published Salmonella data
set. We conclude that QNet can provide a useful alternative to NNet if distance
data are not available or a character-based approach is preferred. Moreover, it
can be used as an aid for determining when a quartet-based tree-building method
may or may not be appropriate for a given data set. QNet is freely available for
download. Split networks are a type of phylogenetic network that allow visualization of
conflict in evolutionary data. We present a new method for constructing such
networks called FlatNetJoining (FlatNJ). A key feature of FlatNJ is that it
produces networks that can be drawn in the plane in which labels may appear
inside of the network. For complex data sets that involve, for example,
non-neutral molecular markers, this can allow additional detail to be visualized
as compared to previous methods such as split decomposition and NeighborNet. We
illustrate the application of FlatNJ by applying it to whole HIV genome
sequences, where recombination has taken place, fluorescent proteins in corals,
where ancestral sequences are present, and mitochondrial DNA sequences from gall
wasps, where biogeographical relationships are of interest. We find that the
networks generated by FlatNJ can facilitate the study of genetic variation in
the underlying molecular sequence data and, in particular, may help to
investigate processes such as intra-locus recombination. FlatNJ has been
implemented in Java and is freely available at
www.uea.ac.uk/computing/software/flatnj. SUMMARY: Split-networks are a generalization of phylogenetic trees that have
proven to be a powerful tool in phylogenetics. Various ways have been developed
for computing such networks, including split-decomposition, NeighborNet, QNet
and FlatNJ. Some of these approaches are implemented in the user-friendly
SplitsTree software package. However, to give the user the option to adjust and
extend these approaches and to facilitate their integration into analysis
pipelines, there is a need for robust, open-source implementations of associated
data structures and algorithms. Here, we present SPECTRE, a readily available,
open-source library of data structures written in Java, that comes complete with
new implementations of several pre-published algorithms and a basic interactive
graphical interface for visualizing planar split networks. SPECTRE also supports
the use of longer running algorithms by providing command line interfaces, which
can be executed on servers or in High Performance Computing environments.
AVAILABILITY AND IMPLEMENTATION: Full source code is available under the GPLv3
license at: https://github.com/maplesond/SPECTRE. SPECTRE's core library is
available from Maven Central at:
https://mvnrepository.com/artifact/uk.ac.uea.cmp.spectre/core. Documentation is
available at:
http://spectre-suite-of-phylogenetic-tools-for-reticulate-evolution.readthedocs.io/en/latest/.
CONTACT: [email protected].
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. |
List 3 apoE mimetics. | COG133, COG112 and Ac-hE18A-NH(2) are apoE mimetics. | |
What are there sex differences in SAMHD1 activity? | The host restriction factor SAMHD1 exists in a hyperphosphorylated, less active state in male-derived macrophages. SAMHD1 is an essential modulator of infectivity in a sex-dependent manner in macrophages, constituting a novel component of sex differences in innate immune control of HIV-1. | BACKGROUND: Macrophages are major targets for HIV-1, contribute to viral
propagation in vivo, and are instrumental in the pathogenesis of HAND. While it
is known that host sex affects HIV-1 viremia and influences the severity of
HIV-1-associated neurocognitive disease, a cellular or molecular basis for these
findings remains elusive.
METHODS: We explored whether sex affects HIV-1 infectivity of primary human
macrophages and CD4+ T cells in vitro.
RESULTS: Macrophages derived from female donors were less susceptible to HIV-1
infection than those derived from males. This sex-dependent difference in
macrophage infectivity was independent of the requirement for CD4/CCR5-mediated
virus entry and was not observed in CD4+ T cells. Investigations into the
mechanism governing these sex-dependent differences revealed that the host
restriction factor SAMHD1 exists in a hyperphosphorylated, less active state in
male-derived macrophages. In addition, the major kinase responsible for SAMHD1
phosphorylation, CDK1, exhibited lower levels of expression in female-derived
macrophages in all tested donor pairs. The sex-dependent differences in viral
restriction imposed by SAMHD1 were abrogated upon its depletion.
CONCLUSIONS: We conclude that SAMHD1 is an essential modulator of infectivity in
a sex-dependent manner in macrophages, constituting a novel component of sex
differences in innate immune control of HIV-1. |
Which enhancers are characterized as latent? | Here, we describe latent enhancers, defined as regions of the genome that in terminally differentiated cells are unbound by TFs and lack the histone marks characteristic of enhancers but acquire these features in response to stimulation. | According to current models, once the cell has reached terminal differentiation,
the enhancer repertoire is completely established and maintained by
cooperatively acting lineage-specific transcription factors (TFs). TFs activated
by extracellular stimuli operate within this predetermined repertoire, landing
close to where master regulators are constitutively bound. Here, we describe
latent enhancers, defined as regions of the genome that in terminally
differentiated cells are unbound by TFs and lack the histone marks
characteristic of enhancers but acquire these features in response to
stimulation. Macrophage stimulation caused sequential binding of
stimulus-activated and lineage-determining TFs to these regions, enabling
deposition of enhancer marks. Once unveiled, many of these enhancers did not
return to a latent state when stimulation ceased; instead, they persisted and
mediated a faster and stronger response upon restimulation. We suggest that
stimulus-specific expansion of the cis-regulatory repertoire provides an
epigenomic memory of the exposure to environmental agents. |
What is the difference between COG133 and COG112? | COG112 results from the fusion of COG133 to a protein transduction domain. | |
Velocardial facial syndrome, otherwise known as Di George syndrome is caused by a deletion in chromosome 21, yes or no? | Velocardial facial syndrome, otherwise known as Di George syndrome is caused by a deletion in chromosome 22. | Most of the children with Di George syndrome and 60% of patients with
velocardiofacial syndrome exhibit a microdeletion within chromosome 22q11. The
phenotypic expression of this chromosomal abnormality is highly variable.
PATIENTS: Forty-nine children, 0 to 15 years of age, were demonstrated as
carriers of a 22q11 microdeletion. The main referral diagnoses were: Di George
syndrome (19 cases), velocardiofacial syndrome (14 cases); congenital heart
defect with dysmorphism (9 cases); hypoparathyroidism (2 cases). The
microdeletion was detected by fluorescent in situ hybridization with probes
specific of the 22q11 region.
RESULTS: Facial dysmorphism was the only constant feature. A congenital heart
defect was present in 84% of cases. Significant hypocalcemia was documented in
51% of cases and thymic hypo or agenesis in 83%. Significant immune deficiency
was documented in nine cases. The most frequent associated defects were urinary
tract malformations (8 cases). A cleft palate was present in height enfants but
velopharyngeal insufficiency was almost constant. Two-thirds of children had
psychomotor delay, and five children exhibited behavioral problems. Of the 35
couples of parents tested, eight mothers were found to be carriers of the
deletion.
CONCLUSION: For the pediatrician, it is essential to know the variability of the
clinical picture. The long-term prognosis is conditioned by the possibility of
mental retardation and learning disabilities. Parents should be tested for the
presence of the deletion. The occurrence of the microdeletion in asymptomatic
relatives raises difficult problems in genetic counselling. New high-resolution cytogenetical technique identified an increased number of
terminal, interstitial and subtelomeric microdeletion as the etiology of many
syndromes of multiple congenital anomalies, mental retardation and facial
dysmorphy. A loss of contiguous genes shows a high phenotypical variability and
at the same time it is significant for genetic prognosis. 1) Variability of
clinical features depends on the size and pathogenetic mechanism of underlying
deletion; 2) Dysmorphic face features are of a characteristic type and can be
somatoscopically recognized; 3) Heart defects and mental retardation are common
features of microdeletion syndromes; 4) New mutations represent the most common
etiology of microdeletions; only 1 to 10% of mutations are transmitted from the
parental gonadal mosaics, from the balanced translocation or from the same
microdeletion in parents; 5) Recurrence risk is low, but it may be as high as
50% in individual cases of inherited mutation; 6) Genetic heterogeneity is high
and the responsible genes can be located at different chromosomes (e.g. Di
George syndrome due to mutation on 22q or 10q) and can also result from
microdeletion or point mutation (in the Shprintzen syndrome 70% represent
microdeletion and 30% point mutation at 22q11, in Rubinstein-Taybi syndrome 10%
cases result from microdeletions and 90% from point mutations); 7) Population
incidence of microdeletions is high (1:4000 to 1:30,000) because their etiologic
mechanism is related to the common unequal crossing over; 8) Imprinting plays a
role in some cases, e.g. Prader-Willi syndrome results from nullisomy of
paternal 15q12 chromosome, Angelman syndrome is related to that of maternal
15q12 chromosome; 9) Prenatal prevention of the high risk familial chromosomal
rearrangements is feasible since the 12th gestation week. The deletion of chromosome 22q11.2 is involved in the majority of DiGeorge or
velo-cardiofacial syndrome. The phenotypic variability was noted in the "CATCH
22" acronym. This acronym doesn't recapitulate the full spectrum of the
symptoms. The diagnosis of this syndrome can be done with the prenatal
diagnosis, with fetal pathology or with a child alive.
METHODS: Review of 52 cases with the microdeletion 22q11. Six cases were
diagnosed during the prenatal period, 12 cases at fetal pathology examination,
and 34 cases during infancy.
RESULTS: Cardiac malformations were the major indications (75%) to search for
the microdeletion. The facial dysmorphy was difficult to diagnose during the
antenatal period or in dead foetus, thereby it was not often recognized. The
renal anomalies usually present in 35% of cases, were diagnosed in only 6 to 16%
of the cases in our study.
CONCLUSION: Phenotypic diversity of the DiGeorge syndrome is important. Its
knowledge allows to better determine the indications of the research of the
microdeletion. 22q11.2. |
Is the protein Asporin related to disease? | Yes,
Accumulating evidence demonstrates the involvement of asporin in OA pathogenesis. Asporin has been reported as a tumor suppressor in breast cancer, while asporin-activated invasion has been described in gastric cancer. | Author information:
(1)Department of Clinical and Molecular Pathology, Institute of Molecular and
Translational Medicine, Faculty of Medicine and Dentistry, Palacky University,
Olomouc, Czech Republic.
(2)Laboratory of Experimental Medicine, Institute of Molecular and Translational
Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech
Republic.
(3)Department of Histology and Embryology, Faculty of Medicine in Hradec
Kralove, Charles University, Hradec Kralove, Czech Republic.
(4)Department of Immunology, Faculty of Medicine and Dentistry, Palacky
University, Olomouc, Czech Republic.
(5)Department of Medical Chemistry and Biochemistry, Institute of Molecular and
Translational Medicine, Faculty of Medicine and Dentistry, Palacky University,
Olomouc, Czech Republic.
(6)Department of Comprehensive Cancer Care, Masaryk Memorial Cancer Institute,
Brno, Czech Republic.
(7)Department of Cytokinetics, Institute of Biophysics, Academy of Sciences of
the Czech Republic, v.v.i., Brno, Czech Republic.
(8)Center of Biomolecular and Cellular Engineering, International Clinical
Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic.
(9)Department of Experimental Biology, Faculty of Science, Masaryk University,
Brno, Czech Republic. Asporin has been implicated as an oncogene in various types of human cancers;
however, the roles of asporin in the development and progression of colorectal
cancer (CRC) have not yet been determined. With clinical samples, we found that
asporin was highly expressed in CRC tissues compared to adjacent normal tissues
and the asporin expression levels were significantly associated with lymph node
metastasis status and TNM stage of the patients. Through knockdown of asporin in
CRC cell lines RKO and SW620 or overexpression of asporin in cell lines HT-29
and LoVo, we found that asporin could enhance wound healing, migration and
invasion abilities of the CRC cells. Further more, with the human umbilical vein
endothelial cells (HUVECs) tube formation assays and the xenograft model, we
found that asporin promoted the tumor growth through stimulating the VEGF
signaling pathway. The portal vein injection models suggested that asporin
overexpression stimulated the liver metastasis of HT29 cell line, while asporin
knockdown inhibited the liver metastasis of RKO cell line. In addition, asporin
was found to augment the phosphorylation of EGFR/src/cortactin signaling
pathway, which might be contributed to the biological functions of asporin in
CRC metastasis. These results suggested that asporin promoted the tumor growth
and metastasis of CRC, and it could be a potential therapeutic target for CRC
patients in future. |
Can TAD disruption lead to disease? | TAD boundaries are insulators of genomic neighborhoods. Τhe disruption of these structures by genomic rearrangements can result in gene misexpression and disease. | In eukaryotes transcriptional regulation often involves multiple long-range
elements and is influenced by the genomic environment. A prime example of this
concerns the mouse X-inactivation centre (Xic), which orchestrates the
initiation of X-chromosome inactivation (XCI) by controlling the expression of
the non-protein-coding Xist transcript. The extent of Xic sequences required for
the proper regulation of Xist remains unknown. Here we use chromosome
conformation capture carbon-copy (5C) and super-resolution microscopy to analyse
the spatial organization of a 4.5-megabases (Mb) region including Xist. We
discover a series of discrete 200-kilobase to 1 Mb topologically associating
domains (TADs), present both before and after cell differentiation and on the
active and inactive X. TADs align with, but do not rely on, several domain-wide
features of the epigenome, such as H3K27me3 or H3K9me2 blocks and
lamina-associated domains. TADs also align with coordinately regulated gene
clusters. Disruption of a TAD boundary causes ectopic chromosomal contacts and
long-range transcriptional misregulation. The Xist/Tsix sense/antisense unit
illustrates how TADs enable the spatial segregation of oppositely regulated
chromosomal neighbourhoods, with the respective promoters of Xist and Tsix lying
in adjacent TADs, each containing their known positive regulators. We identify a
novel distal regulatory region of Tsix within its TAD, which produces a long
intervening RNA, Linx. In addition to uncovering a new principle of
cis-regulatory architecture of mammalian chromosomes, our study sets the stage
for the full genetic dissection of the X-inactivation centre. Author information:
(1)Max Planck Institute for Molecular Genetics, RG Development & Disease, 14195
Berlin, Germany; Institute for Medical and Human Genetics, Charité
Universitätsmedizin Berlin, 13353 Berlin, Germany.
(2)Institute for Medical and Human Genetics, Charité Universitätsmedizin Berlin,
13353 Berlin, Germany.
(3)Medical Genetics Unit, Policlinico Tor Vergata University Hospital, 00133
Rome, Italy.
(4)Institute of Human Genetics Biozentrum, Julius Maximilian University of
Würzburg, 97070 Würzburg, Germany.
(5)Medical Genetics Department, Istanbul Medical Faculty, Istanbul University,
34093 Istanbul, Turkey.
(6)Department of Pediatrics, School of Medicine, University of Utah, Salt Lake
City, UT 84108, USA.
(7)Instituto de Genética Médica y Molecular (INGEMM), IdiPAZ, Hospital
Universitario La Paz, 28046 Madrid, Spain; U753 Centro de Investigación
Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III,
28046 Madrid, Spain.
(8)Service de Génétique, C.H.U. de Poitiers, 86021 Poitiers, France.
(9)Department Developmental Genetics, Max Planck Institute for Molecular
Genetics, 14195 Berlin, Germany.
(10)Max Planck Institute for Molecular Genetics, RG Development & Disease, 14195
Berlin, Germany.
(11)Department of Computational Molecular Biology, Max Planck Institute for
Molecular Genetics, 14195 Berlin, Germany.
(12)Genomics Division, MS 84-171, Lawrence Berkeley National Laboratory,
Berkeley, CA 94720, USA.
(13)Max Planck Institute for Molecular Genetics, Sequencing Core Facility, 14195
Berlin, Germany.
(14)Max Planck Institute for Molecular Genetics, RG Development & Disease, 14195
Berlin, Germany; Berlin-Brandenburg Center for Regenerative Therapies (BCRT),
Charité Universitätsmedizin Berlin, 13353 Berlin, Germany.
(15)Max Planck Institute for Molecular Genetics, RG Development & Disease, 14195
Berlin, Germany; Institute for Medical and Human Genetics, Charité
Universitätsmedizin Berlin, 13353 Berlin, Germany; Berlin-Brandenburg Center for
Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, 13353 Berlin,
Germany.
(16)Genomics Division, MS 84-171, Lawrence Berkeley National Laboratory,
Berkeley, CA 94720, USA; U.S. Department of Energy Joint Genome Institute,
Walnut Creek, CA 94598, USA; School of Natural Sciences, University of
California, Merced, CA 95343, USA.
(17)Max Planck Institute for Molecular Genetics, RG Development & Disease, 14195
Berlin, Germany; Institute for Medical and Human Genetics, Charité
Universitätsmedizin Berlin, 13353 Berlin, Germany; Berlin-Brandenburg Center for
Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, 13353 Berlin,
Germany. Electronic address: [email protected]. BACKGROUND: The human genome is highly organized in the three-dimensional
nucleus. Chromosomes fold locally into topologically associating domains (TADs)
defined by increased intra-domain chromatin contacts. TADs contribute to gene
regulation by restricting chromatin interactions of regulatory sequences, such
as enhancers, with their target genes. Disruption of TADs can result in altered
gene expression and is associated to genetic diseases and cancers. However, it
is not clear to which extent TAD regions are conserved in evolution and whether
disruption of TADs by evolutionary rearrangements can alter gene expression.
RESULTS: Here, we hypothesize that TADs represent essential functional units of
genomes, which are stable against rearrangements during evolution. We
investigate this using whole-genome alignments to identify evolutionary
rearrangement breakpoints of different vertebrate species. Rearrangement
breakpoints are strongly enriched at TAD boundaries and depleted within TADs
across species. Furthermore, using gene expression data across many tissues in
mouse and human, we show that genes within TADs have more conserved expression
patterns. Disruption of TADs by evolutionary rearrangements is associated with
changes in gene expression profiles, consistent with a functional role of TADs
in gene expression regulation.
CONCLUSIONS: Together, these results indicate that TADs are conserved building
blocks of genomes with regulatory functions that are often reshuffled as a whole
instead of being disrupted by rearrangements. |
Is L-4F an apoE mimetic peptide? | No, L-4F is an apoA-I mimetic peptide. | Pancreatic cancer is an aggressive maligcy that is unresponsive to
conventional radiation and chemotherapy. Therefore, development of novel immune
therapeutic strategies is urgently needed. L-4F, an Apolipoprotein A-I (ApoA-I)
mimetic peptide, is engineered to mimic the anti-inflammatory and anti-oxidative
functionalities of ApoA-I. In this work, H7 cells were orthotopically implanted
in C57BL/6 mice and treated with L-4F. Then, pancreatic cancer progression and
the inflammatory microenvironment were investigated in vivo. The cytotoxicity of
L-4F toward H7 cells was assessed in vitro. Furthermore, we investigated the
effects of L-4F on macrophage polarization by analyzing the polarization and
genes of mouse bone marrow-derived macrophages in vitro. The results show that
L-4F substantially reduced the tumorigenicity of H7 cells. L-4F inhibited
inflammation by reducing the accumulation of inflammatory cells, such as
IL-17A-, IL-4-, GM-CSF-, IL-1β-, and IL-6-producing cells and Th1 and Th17.
Notably, L-4F also decreased the percentage of macrophages in tumor tissues,
especially M2 macrophages (CD11b+F4/80+CD206+), which was also confirmed in
vitro. Additionally, the expression of the M2 marker genes Arg1, MRC1, and CCL22
and the inflammatory genes IL-6, iNOS, and IL-12 was decreased by L-4F,
indicating that L-4F prevents M2 type macrophage polarization. However, L-4F
could not directly attenuate H7 cell invasion or proliferation and did not
induce apoptosis. In addition, L-4F potently down-regulated STAT3, JNK and ERK
signaling pathways but not affects the phosphorylation of p38 in RAW 264.7
cells. These results suggest that L-4F exhibits an effective therapeutic effect
on pancreatic cancer progression by inhibiting tumor-associated macrophages and
inflammation. |
Which cells secrete lactotransferrin? | We conclude that lactotransferrin represents a late stage differentiation marker of neutrophils, macrophages and distinct subtypes of dendritic cells. | Considerable effort has been expended to identify genes that account for myeloid
lineage commitment and development. However, currently available non-invasive
mouse models utilize myeloid-specific reporters that are significantly expressed
in hematopoietic stem cells as well as lymphoid compartments. Here, we describe
a myeloid-specific marker that is not shared by any other lineage. We show that
lactotransferrin mRNA is expressed by Gr-1(+)/CD11b(+) cells in the bone marrow,
as opposed to hematopoietic stem cells or any peripheral cell population. To
follow the progeny of lactotransferrin-expressing bone marrow cells, we
generated a mouse model in which a reporter gene is irreversibly activated from
the lactotransferrin-promoter. We found that lactotransferrin-reporter labels a
majority of neutrophils, monocytes, macrophages and distinct subtypes of
dendritic cells, while excluding T, B, natural killer cells,
interferon-producing killer dendritic cells, plasmacytoid dendritic cells,
erythrocytes and eosinophils. Lactotransferrin-reporter(-) bone marrow cells
retain lymphoid, erythroid and long-term repopulating potential, while
lactotransferrin-reporter(+) bone marrow cells confer only myeloid, but not
lymphoid potential. We conclude that lactotransferrin represents a late stage
differentiation marker of neutrophils, macrophages and distinct subtypes of
dendritic cells. |
Which plant does oleuropein originate from? | Oleuropein originates from olive trees, and is specifically found in olive leaf extracts. | Olive leaves are rich in polyphenolic compounds that are known to have
antioxidant, antimicrobial, and anti-inflammatory activities. Therefore, olive
leaf extract (OLE) is considered as a natural supplement. In this study we
evaluated the antibacterial and the anti-inflammatory effect of OLE and its
individual phenolic components in vitro. Polymorphonuclear cells (PMNCs) were
isolated from the whole blood using Histopaque solution and cultured in
RPMI-enriched medium. Tumor necrosis factor α (TNFα) level was determined by
ELISA after 24 h of lipopolysaccharide stimulation. The antibacterial activity
of OLE was determined by well diffusion assay. We found a significant decrease
in TNFα secretion level in PMNCs culture treated with OLE. Oleuropein is the
only OLE component that has shown anti-inflammatory effects at a concentration
of 20 μg/mL. Furthermore, OLE exhibited antibacterial activity against some gram
positive bacterial strains; however, gram negative bacterial strains were
resistant to OLE. Downregulation of TNFα secretion in PMNCs culture in response
to OLE treatment indicates that this polyphenol-rich extract has an
anti-inflammatory effect, and oleuropein is the major OLE component responsible
for this effect. The antibacterial activity of OLE is limited to gram positive
bacteria. |
Reslizumab is a humanized monoclonal antibody to treat what specific type of asthma? | Reslizumab in the treatment of severe eosinophilic asthma: an update. | Within the context of the heterogeneous phenotypic stratification of asthmatic
population, many patients are characterized by moderate-to-severe eosinophilic
asthma, not adequately controlled by relatively high dosages of inhaled and even
oral corticosteroids. Therefore, these subjects can obtain significant
therapeutic benefits by additional biologic treatments targeting interleukin-5
(IL-5), given the key pathogenic role played by this cytokine in maturation,
activation, proliferation, and survival of eosinophils. In particular,
reslizumab is a humanized anti-IL-5 monoclonal antibody that has been found to
be an effective and safe add-on therapy, capable of decreasing asthma
exacerbations and significantly improving disease control and lung function in
patients experiencing persistent allergic or nonallergic eosinophilic asthma,
despite the regular use of moderate-to-high doses of inhaled corticosteroids.
These important therapeutic effects of reslizumab, demonstrated by several
controlled clinical trials, have led to the recent approval by US Food and Drug
Administration of its use, together with other antiasthma medications, for the
maintece treatment of patients suffering from severe uncontrolled asthma. The starting point for this drug was the growing realization that eosinophils
appeared to be associated with a severe form of asthma in which patients were
subject to exacerbations of their condition that could not be adequately managed
using inhaled and/or oral corticosteroids. Studies of the pathophysiology of
eosinophils revealed that they produce many bioactive compounds that contribute
to the pathophysiology of a number of diseases including asthma. Interleukin-5
(IL-5) in particular is an important factor in some forms of severe asthma. A
rat antibody to IL-5 (39D10) was humanized producing the product now know as
reslizumab. However, initial studies of this antibody in patients with asthma
were unsuccessful. It was only when the importance of the eosinophilic asthma
endotype was recognized that reslizumab was found to indeed reduce the severity
and exacerbations of asthma in patients who were inadequately treated by inhaled
and/ or oral corticosteroids. These studies have determined that reslizumab is a
valuable drug for the management of such patients provided that they have an
eosinophil count of > 400 cells/mcL. Because a very small percentage of patients
receiving reslizumab may experience anaphylaxis, reslizumab must be only given
in a facility with adequate facilities and by a health professional trained in
the management of anaphylaxis. Human eosinophils represent approximately 1% of peripheral blood leukocytes.
However, these cells have the propensity to leave the blood stream and migrate
into inflamed tissues. Eosinophilic inflammation is present in a significant
proportion of patients with severe asthma. Asthma is a chronic inflammatory
disorder that affects more than 315 million people worldwide, with 10% having
severe uncontrolled disease. Although the majority of patients can be
efficiently treated, severe asthmatics continue to be uncontrolled and are at
risk of exacerbations and even death. Interleukin-5 (IL-5) plays a fundamental
role in eosinophil differentiation, maturation, activation and inhibition of
apoptosis. Therefore, targeting IL-5 is an appealing approach to the treatment
of patients with severe eosinophilic asthma. Reslizumab, a humanized anti-IL-5
monoclonal antibody, binds with high affinity to amino acids 89-92 of IL-5 that
are critical for binding to IL-5 receptor α. Two phase III studies have
demonstrated that reslizumab administration in adult patients with severe asthma
and eosinophilia (≥400 cells/μL) improved lung function, asthma control, and
symptoms. Thus, the use of blood eosinophils as a baseline biomarker could help
to select patients with severe uncontrolled asthma who are likely to achieve
benefits in asthma control with reslizumab. In conclusion, targeted therapy with
reslizumab represents one step closer to precision medicine in patients with
severe eosinophilic asthma. A marked heterogeneity is exhibited by asthma both clinically and at the
molecular level with different phenotypes driven by diverse mechanistic pathways
that require specifically targeted treatments. Biologics aimed at IL-4/13, IL-5
or IgE are proven or potentially effective treatments for patients with
difficult to treat eosinophilic asthma. Importantly, it is now widely accepted
that biologic-based therapies give significant clinical improvements in those
patient populations where asthma phenotypes are taken into account. Such asthma
phenotypes have been identified by reproducible and straightforward
discriminatory biomarkers. This short review discusses recent studies of the
effectiveness of the anti-IL-5 reslizumab in relation to the use of simple
reproducible biomarkers in eosinophilic asthma. RATIONALE: Reslizumab is a humanized anti-IL-5 monoclonal antibody used as
add-on maintece treatment for patients with uncontrolled eosinophilic asthma.
OBJECTIVES: To predict response and nonresponse to intravenous reslizumab at 52
weeks with an algorithm we developed based on clinical indicators from pivotal
clinical trials.
METHODS: Patients aged 18 years and older who met Global Initiative for Asthma 4
or 5 criteria and received intravenous reslizumab (n = 321) in two trials (
www.clinicaltrials.gov identifiers, NCT01287039 and NCT01285323) were selected
as the data source. A mathematical model was constructed that was based on
change from baseline to 16 weeks in Asthma Control Questionnaire and Asthma
Quality of Life Questionnaire scores and FEV1, and number of clinical asthma
exacerbations during the year before enrollment and in the first 16 weeks of
treatment, and these measures were evaluated for their ability to predict the
outcome at 52 weeks: responder, nonresponder, or indeterminate.
MEASUREMENTS AND MAIN RESULTS: The algorithm predicted that 276 patients would
be classified as responders; in 248 (89.9%), the prediction was correct. In
comparison, 26 patients were predicted to be nonresponders; 50.0% of these
predictions were correct. Nineteen patients were classified as indeterminate.
The algorithm had 95.4-95.5% sensitivity and 40.6-54.1% specificity. Jackknife
and cross-study validation confirmed the robustness of the algorithm.
CONCLUSIONS: Our algorithm enabled prediction at 16 weeks of treatment of the
response to intravenous reslizumab treatment at 52 weeks, but it was not
suitable for predicting nonresponse. A positive score at 16 weeks should
encourage continued treatment, and a negative score should prompt close
monitoring to determine whether discontinuation is warranted. |
What is the function of the protein Magt1? | The magnesium transporter 1 (MAGT1) is a critical regulator of basal intracellular free magnesium ([Mg2+]i) levels. | The magnesium transporter 1 (MAGT1) is a critical regulator of basal
intracellular free magnesium ([Mg2+]i) levels. It has been shown that MAGT1 was
involved in the disorder in Mg2+ homeostasis after Epstein-Barr virus (EBV)
infection. Here, we identified the effects of MAGT1-mediated disturbance of Mg2+
homeostasis on chronic hepatitis B virus (HBV)-infected natural killer (NK) and
CD8+ T cells. The expression of MAGT1 was gradually decreased with the increase
of infected time in CD8+ T cells, but not with that in NK cells, of the
patients. Decreased level of intracellular free Mg2+ ([Mg2+]i) leads to
defective expression of programmed cell death 1 (PD-1) and the NK activating
receptor (NKG2D) in NK and CD8+ T cells. Our data illustrate that [Mg2+]i plays
a key role in control of HBV infection. Cation homeostasis, in relation to various immune-suppressive diseases, is a
novel field of investigation. Recently, patients with a loss-of-function
mutation in magnesium transporter 1 (MAGT1) were reported to present a
dysregulated Mg2+ homeostasis in T lymphocytes. Using Magt1-knockout mice
(Magt1-/y ), we show that Mg2+ homeostasis was impaired in Magt1-/y B cells and
Ca2+ influx was increased after BCR stimulation, whereas T and NK cell function
was unaffected. Consequently, mutant B cells displayed an increased
phosphorylation of BCR-related proteins differentially affecting protein kinase
C activation. These in vitro findings translated into increased frequencies of
CD19+ B cells and marginal zone B cells and decreased frequencies of plasma
cells among CD45+ splenocytes in vivo. Altogether, our study demonstrates for
the first time, to our knowledge, that abolished MAGT1 function causes
imbalanced cation homeostasis and developmental responses in B cells. Therefore,
this study might contribute to a further understanding of B cell-related
pathologies. |
Can oleuropein aglycone interfere with amyloid aggregation? | Yes, oleuropein aglycone interferes in vitro and in vivo with amyloid aggregates. | Author information:
(1)Department of Biomedical, Experimental and Clinical Sciences 'Mario Serio',
University of Florence, Viale Morgagni, 50 50134 Florence, Italy; Department of
Neuroscience, Psychology, Area of Medicine and Health of the Child of the
University of Florence, Viale Pieraccini, 6, 50139 Florence, Italy.
(2)Department of Physics, University of Genova, via Dodecaneso 33, 16146,
Genova, Italy.
(3)Department of Molecular Medicine, Institute of Biochemistry, University of
Pavia, Viale Taramelli 3/B, 27100 Pavia, Italy.
(4)Department of Molecular Medicine, Institute of Biochemistry, University of
Pavia, Viale Taramelli 3/B, 27100 Pavia, Italy; Wolfson Drug Discovery Unit,
Centre for Amyloidosis and Acute Phase Proteins, Division of Medicine Royal Free
Campus, University College London, NW3 2PF London, UK.
(5)Department of Biomedical, Experimental and Clinical Sciences 'Mario Serio',
University of Florence, Viale Morgagni, 50 50134 Florence, Italy.
(6)Department of Molecular Medicine, Institute of Biochemistry, University of
Pavia, Viale Taramelli 3/B, 27100 Pavia, Italy; Wolfson Drug Discovery Unit,
Centre for Amyloidosis and Acute Phase Proteins, Division of Medicine Royal Free
Campus, University College London, NW3 2PF London, UK; Interuniversity Center
for the Study of Neurodegenerative Diseases (CIMN), Florence, Italy.
(7)Department of Biomedical, Experimental and Clinical Sciences 'Mario Serio',
University of Florence, Viale Morgagni, 50 50134 Florence, Italy;
Interuniversity Center for the Study of Neurodegenerative Diseases (CIMN),
Florence, Italy.
(8)Department of Biomedical, Experimental and Clinical Sciences 'Mario Serio',
University of Florence, Viale Morgagni, 50 50134 Florence, Italy;
Interuniversity Center for the Study of Neurodegenerative Diseases (CIMN),
Florence, Italy. Electronic address: [email protected]. |
What is the function of the transcriptional co-activator p300? | The transcriptional co-activator p300 is a histone acetyltransferase (HAT) that is typically recruited to transcriptional enhancers and regulates gene expression by acetylating chromatin. | p300, a transcriptional co-activator with histone acetyl transferase (HAT)
activity, plays an essential role in the pathogenesis of cardiomyocyte
hypertrophy in response to multiple pro-hypertrophic stimuli including
hyperglycemia. However, the precise mechanisms by which p300 expression is
regulated remain unclear. The purpose of this study was to investigate the role
of miR-150, a potential p300-targeting microRNA (miRNA), in the
post-transcriptional control of p300 expression and cardiomyocyte hypertrophy
induced by high glucose. We observed that the expression of miR-150 was
significantly reduced, whereas the expression of p300 was strongly elevated,
concomitant with cardiomyocyte hypertrophy, in the hearts of diabetic rats
compared with normal controls. Similar alterations were observed in neonatal rat
cardiomyocytes that had been exposed to high levels of glucose. miR-150 mimics
inhibited p300 3'-UTR luciferase reporter activity, as well as endogenous p300
expression. In addition, miR-150 mimics prevented glucose-induced cardiomyocyte
hypertrophy. Co-transfection with a p300 expression vector and miR-150 mimics
reversed the protective effect of miR-150 on cardiomyocyte hypertrophy. We
further showed that the high glucose-mediated activation of PKCβ(2) in turn
mediated the down-regulation of miR-150 expression. These data demonstrated a
novel upstream role for miR-150 in p300-mediated cardiomyocyte hypertrophy and
revealed a previously uncharacterized miRNAs and HATs cross-talk mechanism for
the hypertrophic phenotype induced by high glucose. The transcriptional co-activator p300 is a histone acetyltransferase (HAT) that
is typically recruited to transcriptional enhancers and regulates gene
expression by acetylating chromatin. Here we show that the activation of p300
directly depends on the activation and oligomerization status of transcription
factor ligands. Using two model transcription factors, IRF3 and STAT1, we
demonstrate that transcription factor dimerization enables the
trans-autoacetylation of p300 in a highly conserved and intrinsically disordered
autoinhibitory lysine-rich loop, resulting in p300 activation. We describe a
crystal structure of p300 in which the autoinhibitory loop invades the active
site of a neighbouring HAT domain, revealing a snapshot of a
trans-autoacetylation reaction intermediate. Substrate access to the active site
involves the rearrangement of an autoinhibitory RING domain. Our data explain
how cellular signalling and the activation and dimerization of transcription
factors control the activation of p300, and therefore explain why gene
transcription is associated with chromatin acetylation. |
What is another name for the plant Sideritis scardica? | Sideritis scardica is also known as ironwort or mountain tea. | |
How are gas vesicle proteins used in imaging? | Gas vesicles (GVs)-a unique class of gas-filled protein nanostructures-have recently been introduced as a promising new class of ultrasound contrast agents that can potentially access the extravascular space and be modified for molecular targeting. | Ultrasound is among the most widely used biomedical imaging modalities, but has
limited ability to image specific molecular targets due to the lack of suitable
oscale contrast agents. Gas vesicles-genetically encoded protein
ostructures isolated from buoyant photosynthetic microbes-have recently been
identified as oscale reporters for ultrasound. Their unique physical
properties give gas vesicles significant advantages over conventional
microbubble contrast agents, including oscale dimensions and inherent
physical stability. Furthermore, as a genetically encoded material, gas vesicles
present the possibility that the oscale mechanical, acoustic, and targeting
properties of an imaging agent can be engineered at the level of its constituent
proteins. Here, we demonstrate that genetic engineering of gas vesicles results
in ostructures with new mechanical, acoustic, surface, and functional
properties to enable harmonic, multiplexed, and multimodal ultrasound imaging as
well as cell-specific molecular targeting. These results establish a
biomolecular platform for the engineering of acoustic omaterials. Gas vesicles (GVs) are a unique class of gas-filled protein ostructures that
are detectable at subomolar concentrations and whose physical properties
allow them to serve as highly sensitive imaging agents for ultrasound and MRI.
Here we provide a protocol for isolating GVs from native and heterologous host
organisms, functionalizing these ostructures with moieties for targeting and
fluorescence, characterizing their biophysical properties and imaging them using
ultrasound and MRI. GVs can be isolated from natural cyanobacterial and
haloarchaeal host organisms or from Escherichia coli expressing a heterologous
GV gene cluster and purified using buoyancy-assisted techniques. They can then
be modified by replacing surface-bound proteins with engineered, heterologously
expressed variants or through chemical conjugation, resulting in altered
mechanical, surface and targeting properties. Pressurized absorbance
spectroscopy is used to characterize their mechanical properties, whereas
dynamic light scattering (DLS)and transmission electron microscopy (TEM) are
used to determine oparticle size and morphology, respectively. GVs can then
be imaged with ultrasound in vitro and in vivo using pulse sequences optimized
for their detection versus background. They can also be imaged with
hyperpolarized xenon MRI using chemical exchange saturation transfer between
GV-bound and dissolved xenon-a technique currently implemented in vitro. Taking
3-8 d to prepare, these genetically encodable ostructures enable multimodal,
noninvasive biological imaging with high sensitivity and potential for molecular
targeting. |
From where is gamabufotalin (GBT) isolated? | gamabufotalin (GBT) was isolated from toad venom. | BACKGROUND: Gamabufotalin (CS-6), a major bufadienolide of Chansu, has been used
for cancer therapy due to its desirable metabolic stability and less adverse
effect. However, the underlying mechanism of CS-6 involved in anti-tumor
activity remains poorly understood.
METHODS: The biological functions of gamabufotalin (CS-6) were investigated by
migration, colony formation and apoptosis assays in NSCLC cells. The nuclear
localization and interaction between transcriptional co-activator p300 and NF-κB
p50/p65 and their binding to COX-2 promoter were analyzed after treatment with
CS-6. Molecular docking study was used to simulate the interaction of CS-6 with
IKKβ. The in vivo anti-tumor efficacy of CS-6 was also analyzed in xenografts
nude mice. Western blot was used to detect the protein expression level.
RESULTS: Gamabufotalin (CS-6) strongly suppressed COX-2 expression by inhibiting
the phosphorylation of IKKβ via targeting the ATP-binding site, thereby
abrogating NF-κB binding and p300 recruitment to COX-2 promoter. In addition,
CS-6 induced apoptosis by activating the cytochrome c and caspase-dependent
apoptotic pathway. Moreover, CS-6 markedly down-regulated the protein levels of
COX-2 and phosphorylated p65 NF-κB in tumor tissues of the xenograft mice, and
inhibited tumor weight and size.
CONCLUSIONS: Our study provides pharmacological evidence that CS-6 exhibits
potential use in the treatment of COX-2-mediated diseases such as lung cancer. Deciding appropriate therapy for multiple myeloma (MM) is challenging because of
the occurrence of multiple chromosomal changes and the fatal nature of the
disease. In the current study, gamabufotalin (GBT) was isolated from toad venom,
and its tumor-specific cytotoxicity was investigated in human MM cells. We found
GBT inhibited cell growth and induced apoptosis with the IC50 values <50 nM.
Mechanistic studies using functional approaches identified GBT as an inhibitor
of c-Myc. Further analysis showed that GBT especially evoked the ubiquitination
and degradation of c-Myc protein, thereby globally repressing the expression of
c-Myc target genes. GBT treatment inhibited ERK and AKT signals, while
stimulating the activation of JNK cascade. An E3 ubiquitin-protein ligase, WWP2,
was upregulated following JNK activation and played an important role in c-Myc
ubiquitination and degradation through direct protein-protein interaction. The
antitumor effect of GBT was validated in a xenograft mouse model and the
suppression of MM-induced osteolysis was verified in a SCID-hu model in vivo.
Taken together, our study identified the potential of GBT as a promising
therapeutic agent in the treatment of MM. Amphibian granular glands provide a wide range of compounds on the skin that
defend against pathogens and predators. We identified three bufadienolides-the
steroid-like compounds arenobufagin, gamabufotalin, and telocinobufagin-from the
boreal toad, Anaxyrus boreas, through liquid chromatography mass spectrometry
(LC/MS). Compounds were detected both after inducing skin gland secretions and
in constitutive mucosal rinses from toads. We described the antimicrobial
properties of each bufadienolide against Batrachochytrium dendrobatidis (Bd), an
amphibian fungal pathogen linked with boreal toad population declines. All three
bufadienolides were found to inhibit Bd growth at similar levels. The maximum Bd
inhibition produced by arenobufagin, gamabufotalin, and telocinobufagin were
approximately 50%, in contrast to the complete Bd inhibition shown by
antimicrobial skin peptides produced by some amphibian species. In addition,
skin mucus samples significantly reduced Bd viability, and bufadienolides were
detected in 15 of 62 samples. Bufadienolides also appeared to enhance growth of
the anti-Bd bacterium Janthinobacterium lividum, and thus may be involved in
regulation of the skin microbiome. Here, we localized skin bacteria within the
mucus layer and granular glands of toads with fluorescent in situ hybridization.
Overall, our results suggest that bufadienolides can function in antifungal
defense on amphibian skin and their production is a potentially convergent trait
similar to antimicrobial peptide defenses found on the skin of other species.
Further studies investigating bufadienolide expression across toad populations,
their regulation, and interactions with other components of the skin mucosome
will contribute to understanding the complexities of amphibian immune defense. |
What are super-enhancers | Super-enhancers are large clusters of enhancers covering the long region of regulatory DNA and are densely occupied by transcription factors, active histone marks, and co-activators. Accumulating evidence points to the critical role that super-enhancers play in cell type-specific development and differentiation, as well as in the development of various diseases. | The transcriptional regulation of genes determines the fate of animal cell
differentiation and subsequent organ development. With the recent progress in
genome-wide technologies, the genomic landscapes of enhancers have been broadly
explored in mammalian genomes, which led to the discovery of novel specific
subsets of enhancers, termed super-enhancers. Super-enhancers are large clusters
of enhancers covering the long region of regulatory DNA and are densely occupied
by transcription factors, active histone marks, and co-activators. Accumulating
evidence points to the critical role that super-enhancers play in cell
type-specific development and differentiation, as well as in the development of
various diseases. Here, I provide a comprehensive description of the optimal
approach for identifying functional units of super-enhancers and their unique
chromatin features in normal development and in diseases, including cancers. I
also review the recent updated knowledge on novel approaches of targeting
super-enhancers for the treatment of specific diseases, such as small-molecule
inhibitors and potential gene therapy. This review will provide perspectives on
using super-enhancers as biomarkers to develop novel disease diagnostic tools
and establish new directions in clinical therapeutic strategies. |
Is Apelin usually decreased in diabetes? | Different studies in both animals and humans have shown that plasma apelin concentrations are usually increased during obesity and type 2 diabetes. | BACKGROUND: Apelin regulates insulin sensitivity and secretion in animals.
However, whether plasma apelin predicts incident diabetes in humans remains
unknown.
METHODS: We studied a cohort including 447 subjects (148 men, 299 women) without
diabetes and followed for an average of 3y. Diabetes was diagnosed by an oral
glucose tolerance test, plasma hemoglobin A1c, and if the subject was taking
medications for diabetes. Plasma apelin-12 at baseline was measured with a
commercial kit.
RESULTS: Plasma apelin concentrations were higher in women than in men at
baseline (p=0.007). During follow-up, 43 subjects developed type 2 diabetes.
Higher plasma apelin concentrations were associated with a higher risk of
diabetes in men (p=0.049) but not in women. Plasma apelin predicted incident
type 2 diabetes in men (hazard ratio, 2.13, 95% CI 1.29-3.51, p<0.05), but not
in women, adjusted for age, family history of diabetes, hemoglobin A1c, body
mass index, hypertension, and HOMA2-IR. Apelin could improve the prediction
ability beyond traditional risk factors in men, and the sensitivity and
specificity of plasma apelin at 0.9ng/ml for this prediction were 63.2% and
58.9%, respectively. In men at risk for diabetes (HbA1c 5.7-6.4%, FPG
100-125mg/dl, or OGTT-2h-PG 140-199mg/dl), the risk for developing diabetes was
higher in those with higher plasma apelin concentration than in those with lower
plasma apelin concentrations (10.6%/year vs. 5.1%/year, p<0.001).
CONCLUSIONS: Plasma apelin is a novel biomarker for predicting type 2 diabetes
in men. Adipose tissue is an enormously active endocrine organ, secreting various
hormones, such as adiponectin, leptin, resistin and visfatin, together with
classical cytokines, such as tumor necrosis factor-alpha (TNF-α) and
interleukin-6 (IL-6). All these adipocytokines play significant roles in the
regulation of energy metabolism, glucose and lipid metabolism, reproduction,
cardiovascular function and immunity. Adipocytokines are significantly regulated
by nutritional status and can directly influence other organ systems, including
brain, liver and skeletal muscle. Adiponectin plays a key role as an
anti-inflammatory hormone. Upregulated expression of resistin, vaspin, apelin
and TNF-α plays a significant role in induction of insulin resistance linked
with obesity and type 2 diabetes. Ghrelin, the circulating peptide, has been
found to stimulate appetite and regulate energy balance. Thus, it can be
considered 1 of the candidate genes for obesity and type 2 diabetes. Omentin is
a novel adipokine produced by visceral adipose tissue. Circulating levels of
omentin are decreased in insulin-resistant states, for example, in obesity and
diabetes. IL-6 plays a vital role in regulating the accumulation of lipids
intramyocardially. Based on the biologic relevance of these adipocytokines, they
can no longer be considered as energy storage sites alone but must also be
considered in metabolic control. Hence, the present review summarizes the
regulatory roles of adipocytokines in diabetes linked with obesity. |
What is a mitosome? | Mitosomes are the simplest and the least well-studied type of anaerobic mitochondria. The mitosomes have abandoned typical mitochondrial traits such as the mitochondrial genome and aerobic respiration and their single role known to date is the formation of iron-sulfur clusters | Pyridine nucleotide transhydrogenase (PNT) catalyzes the direct transfer of a
hydride-ion equivalent between NAD(H) and NADP(H) in bacteria and the
mitochondria of eukaryotes. PNT was previously postulated to be localized to the
highly divergent mitochondrion-related organelle, the mitosome, in the
anaerobic/microaerophilic protozoan parasite Entamoeba histolytica based on the
potential mitochondrion-targeting signal. However, our previous proteomic study
of isolated phagosomes suggested that PNT is localized to organelles other than
mitosomes. An immunofluorescence assay using anti-E. histolytica PNT (EhPNT)
antibody raised against the NADH-binding domain showed a distribution to the
membrane of numerous vesicles/vacuoles, including lysosomes and phagosomes. The
domain(s) required for the trafficking of PNT to vesicles/vacuoles was examined
by using amoeba transformants expressing a series of carboxyl-terminally
truncated PNTs fused with green fluorescent protein or a hemagglutinin tag. All
truncated PNTs failed to reach vesicles/vacuoles and were retained in the
endoplasmic reticulum. These data indicate that the putative targeting signal is
not sufficient for the trafficking of PNT to the vesicular/vacuolar compartments
and that full-length PNT is necessary for correct transport. PNT displayed a
smear of >120 kDa on SDS-PAGE gels. PNGase F and tunicamycin treatment, chemical
degradation of carbohydrates, and heat treatment of PNT suggested that the
apparent aberrant mobility of PNT is likely attributable to its hydrophobic
nature. PNT that is compartmentalized to the acidic compartments is
unprecedented in eukaryotes and may possess a unique physiological role in E.
histolytica. BACKGROUND: Mitochondria of opisthokonts undergo permanent fission and fusion
throughout the cell cycle. Here, we investigated the dynamics of the mitosomes,
the simplest forms of mitochondria, in the anaerobic protist parasite Giardia
intestinalis, a member of the Excavata supergroup of eukaryotes. The mitosomes
have abandoned typical mitochondrial traits such as the mitochondrial genome and
aerobic respiration and their single role known to date is the formation of
iron-sulfur clusters.
RESULTS: In live experiments, no fusion events were observed between the
mitosomes in G. intestinalis. Moreover, the organelles were highly prone to
becoming heterogeneous. This suggests that fusion is either much less frequent
or even absent in mitosome dynamics. Unlike in mitochondria, division of the
mitosomes was absolutely synchronized and limited to mitosis. The association of
the nuclear and the mitosomal division persisted during the encystation of the
parasite. During the segregation of the divided mitosomes, the subset of the
organelles between two G. intestinalis nuclei had a prominent role.
Surprisingly, the sole dynamin-related protein of the parasite seemed not to be
involved in mitosomal division. However, throughout the cell cycle, mitosomes
associated with the endoplasmic reticulum (ER), although none of the known
ER-tethering complexes was present. Instead, the ER-mitosome interface was
occupied by the lipid metabolism enzyme long-chain acyl-CoA synthetase 4.
CONCLUSIONS: This study provides the first report on the dynamics of mitosomes.
We show that together with the loss of metabolic complexity of mitochondria,
mitosomes of G. intestinalis have uniquely streamlined their dynamics by
harmonizing their division with mitosis. We propose that this might be a
strategy of G. intestinalis to maintain a stable number of organelles during
cell propagation. The lack of mitosomal fusion may also be related to the
secondary reduction of the organelles. However, as there are currently no
reports on mitochondrial fusion in the whole Excavata supergroup, it is possible
that the absence of mitochondrial fusion is an ancestral trait common to all
excavates. |
What is the price of KYMRIAH treatment in 2019? | Kymriah, produced by Novartis has a price tag of US$475,000. | Chimeric antigen receptor (CAR) T cells represent a medical and scientific
breakthrough that may represent a paradigm for the future of personalized
medicine in the age of cancer immunotherapy. As with many new cancer agents,
such novel and incredible results come with a high price. At the time of the
writing of this article, there are two CAR T cells available, Kymriah, produced
by Novrtis with a price tag of US$475,000 and Yescarta produced by Gilead
Pharmaceuticals with a price tag of US$373,000, neither price including the
required hospital admission in order to administer the agent in addition to
potential treatment of side effects. There are several issues that are
imperative to recognize when understanding the high cost, however the two more
pertinent issues are low availability of the agent and no billing code. While
only approved for less than a year, there are thoughts about how to bring the
price down with more approved CAR T cells and more center with the ability to
administer this therapy, however results may be years away before they are
realized. In the short term, insurance companies are grappling over how to pay
for CAR T therapy, with one of the biggest voids concerning the absence of a
billing code for CAR T cells. Regardless, its high price tag highlights moral
issues underlying value-based payments and whether the treatment is worth the
cost while evaluating the juxtaposition of life years and monetary values. As
CAR T cells expand the boundaries of immunotherapy with extraordinary results,
the need for a lower price in combination for more availability of CAR T cells
will grow until some of these fundamental issues are addressed. |
Human dihydroorotate dehydrogenase is a drug target and is involved in what biosynthetic pathway | Dihydroorotate dehydrogenase (DHODH) mediates the fourth step of de novo pyrimidine biosynthesis | Dihydroorotase and dihydroorotate dehydrogenase, two enzymes of the pyrimidine
biosynthetic pathway, were purified from Plasmodium berghei to apparent
homogeneity. Orotate and a series of 5-substituted derivatives were found to
inhibit competitively the purified enzymes from the malaria parasite. The order
of effectiveness as inhibitors on pyrimidine ring cleavage reaction for
dihydroorotase was 5-fluoro orotate greater than 5-amino orotate, 5-methyl
orotate greater than orotate greater than 5-bromo orotate greater than 5-iodo
orotate with Ki values of 65, 142, 166, 860, 2200 and greater than 3500 microM,
respectively. 5-Fluoro orotate and orotate were the most effective inhibitors
for dihydroorotate dehydrogenase. In vitro, 5-fluoro orotate and 5-amino orotate
caused 50% inhibition of the growth of P. falciparum at concentrations of 10 nM
and 1 microM, respectively. In mice infected with P. berghei, these two orotate
analogs at a dose of 25 mg/kg body weight eliminated parasitemia after a 4-day
treatment, an effect comparable to that of the same dose of chloroquine. The
infected mice treated with 5-fluoro orotate at a lower dose of 2.5 mg/kg had a
95% reduction in parasitemia. The effects of the more potent compounds tested in
combination with inhibitors of other enzymes of this pathway on P. falciparum in
vitro and P. berghei in vivo are currently under investigation. These results
suggest that the pyrimidine biosynthetic pathway in the malarial parasite may be
a target for the design of antimalarial drugs. The novel anticancer drug candidate brequinar sodium (DuP 785, NSC 368390,
6-fluoro-2-(2'-fluoro-1,1'-biphenyl-4-yl)-3-methyl-4-quinoline- carboxylic acid
sodium salt) was shown previously to be an inhibitor of dihydroorotate
dehydrogenase, the fourth enzyme of the de novo pyrimidine biosynthetic pathway.
Brequinar sodium inhibits the activity of this enzyme isolated from mammalian
sources only but not those forms isolated from yeast or bacteria, which also use
ubiquinone as the cofactor. Brequinar sodium also does not inhibit the activity
of a soluble Zymobacterium oroticum dihydroorotate dehydrogenase which uses NAD+
as a cofactor. Brequinar sodium inhibits L1210 dihydroorotate dehydrogenase with
mixed inhibition kinetics with respect to either the substrate (dihydroorotate)
or the cofactor (ubiquinone Q6) with Ki' values in the 5-8 nM range. Our results
suggest that brequinar sodium inhibits dihydroorotate dehydrogenase by binding
to the enzyme at a unique site that is distinct from the dihydroorotate or the
ubiquinone-binding site. This binding site appears to be unique to the mammalian
enzyme, because brequinar sodium does not inhibit the yeast, Escherichia coli,
or Z. oroticum forms of the enzyme. The novel anticancer drug candidate brequinar sodium [DuP 785, NSC 368390,
6-fluoro-2-(2'-fluoro-1,1'-biphenyl-4-yl)-3-methyl-4-quinoline carboxylic acid
sodium salt] inhibits dihydroorotate dehydrogenase, the fourth enzyme in the de
novo pyrimidine biosynthetic pathway leading to the formation of UMP. Sixty-nine
quinoline 4-carboxylic acid analogs were analyzed as inhibitors of L1210
dihydroorotate dehydrogenase. This structure-activity relationship study
identified three critical regions of brequinar sodium and its analogs, where
specific substitutions are required for the inhibition of the activity of
dihydroorotate dehydrogenase. The three principal regions are: (i) the C(2)
position where bulky hydrophobic substituents are necessary, (ii) the C(4)
position which has a strict requirement for the carboxylic acid and its
corresponding salts, and (iii) the benzo portion of the quinoline ring with
appropriate substitutions. These results will be useful in the elucidation of
the precise nature of the interaction between brequinar sodium and
dihydroorotate dehydrogenase. Dihydroorotate dehydrogenase (DHOD) is the fourth enzyme in the de novo
pyrimidine biosynthetic pathway and is essential in Trypanosoma cruzi, the
parasitic protist causing Chagas' disease. T. cruzi and human DHOD have
different biochemical properties, including the electron acceptor capacities and
cellular localization, suggesting that T. cruzi DHOD may be a potential
chemotherapeutic target against Chagas' disease. Here, we report nucleotide
sequence polymorphisms of T. cruzi DHOD genes and the kinetic properties of the
recombit enzymes. T. cruzi Tulahuen strain possesses three DHODgenes: DHOD1
and DHOD2, involved in the pyrimidine biosynthetic (pyr) gene cluster on an 800
and a 1000 kb chromosomal DNA, respectively, and DHOD3, located on an 800 kb
DNA. The open reading frames of all three DHOD genes are comprised of 942 bp,
and encode proteins of 314 amino acids. The three DHOD genes differ by 26
nucleotides, resulting in replacement of 8 amino acid residues. In contrast, all
residues critical for constituting the active site are conserved among the three
proteins. Recombit T. cruzi DHOD1 and DHOD2 expressed in E. coli possess
similar enzymatic properties, including optimal pH, optimal temperature, Vmax,
and Km for dihydroorotate and fumarate. In contrast, DHOD3 had a higher Vmax and
Km for both substrates. Orotate competitively inhibited all three DHOD enzymes
to a comparable level. These results suggest that, despite their genetic
variations, kinetic properties of the three T. cruziDHODs are conserved. Our
findings facilitate further exploitation of T. cruzi DHOD inhibitors, as
chemotherapeutic agents against Chagas' disease. Pyrimidine biosynthesis presents an attractive drug target in malaria parasites
due to the absence of a pyrimidine salvage pathway. A set of compounds designed
to inhibit the Plasmodium falciparum pyrimidine biosynthetic enzyme
dihydroorotate dehydrogenase (PfDHODH) was synthesized. PfDHODH-specific
inhibitors with low omolar binding affinities were identified that bind in
the N-terminal hydrophobic channel of dihydroorotate dehydrogenase, the presumed
site of ubiquinone binding during oxidation of dihydroorotate to orotate. These
compounds also prevented growth of cultured parasites at low micromolar
concentrations. Models that suggest the mode of inhibitor binding is based on
shape complementarity, matching hydrophobic regions of inhibitor and enzyme, and
interaction of inhibitors with amino acid residues F188, H185, and R265 are
supported by mutagenesis data. These results further highlight PfDHODH as a
promising new target for chemotherapeutic intervention in prevention of malaria
and provide better understanding of the factors that determine specificity over
human dihydroorotate dehydrogenase. Pyrimidine biosynthesis is an attractive drug target in a variety of organisms,
including humans and the malaria parasite Plasmodium falciparum. Dihydroorotate
dehydrogenase, an enzyme catalyzing the only redox reaction of the pyrimidine
biosynthesis pathway, is a well-characterized target for chemotherapeutical
intervention. In this study, we have applied SPROUT-LeadOpt, a software package
for structure-based drug discovery and lead optimization, to improve the binding
of the active metabolite of the anti-inflammatory drug leflunomide to the target
cavities of the P. falciparum and human dihydroorotate dehydrogenases. Following
synthesis of a library of compounds based upon the SPROUT-optimized molecular
scaffolds, a series of inhibitors generally showing good inhibitory activity was
obtained, in keeping with the SPROUT-LeadOpt predictions. Furthermore, cocrystal
structures of five of these SPROUT-designed inhibitors bound in the ubiquinone
binding cavity of the human dihydroorotate dehydrogenase are also analyzed. Malaria remains a globally prevalent infectious disease that leads to
significant morbidity and mortality. While there are a number of drugs approved
for its treatment, drug resistance has compromised most of them, making the
development of new drugs for the treatment and prevention of malaria essential.
The completion of the Plasmodium falciparum genome and a growing understanding
of parasite biology are fueling the search for novel drug targets. Despite this,
few targets have been chemically validated in vivo. The pyrimidine biosynthetic
pathway illustrates one of the best examples of successful identification of
anti-malarial drug targets. This review focuses on recent studies to exploit the
fourth enzyme in the de novo pyrimidine biosynthetic pathway of P. falciparum,
dihydroorotate dehydrogenase (PfDHODH), as a new target for drug discovery.
Several chemical scaffolds have been identified by high throughput screening as
potent inhibitors of PfDHODH and these show strong selectivity for the malarial
enzyme over that from the human host. Potent activity against parasites in whole
cell models with good correlation between activity on the enzyme and the
parasite have also been observed for a number of the identified series. Lead
optimization of a triazolopyrimidine-based series has identified an analog with
prolonged plasma exposure, that is orally bioavailable, and which shows good
efficacy against the in vivo mouse model of the disease. These data provide
strong evidence that PfDHODH is a validated target for the identification of new
antimalarial chemotherapy. The challenge remains to identify compounds with the
necessary combination of potency and metabolic stability to allow identification
of a clinical candidate. The pyrimidine biosynthesis pathway in the protozoan pathogen Toxoplasma gondii
is essential for parasite growth during infection. To investigate the properties
of dihydroorotate dehydrogenase (TgDHOD), the fourth enzyme in the T. gondii
pyrimidine pathway, we expressed and purified recombit TgDHOD. TgDHOD
exhibited a specific activity of 84U/mg, a k(cat) of 89s(-1), a K(m)=60μM for
l-dihydroorotate, and a K(m)=29μM for decylubiquinone (Q(D)). Quinones lacking
or having short isoprenoid side chains yielded lower k(cat)s than Q(D). As
expected, fumarate was a poor electron acceptor for this family 2 DHOD. The
IC(50)s determined for A77-1726, the active derivative of the human DHOD
inhibitor leflunomide, and related compounds MD249 and MD209 were, 91μM, 96μM,
and 60μM, respectively. The enzyme was not significantly affected by brequinar
or TTFA, known inhibitors of human DHOD, or by atovaquone. DSM190, a known
inhibitor of Plasmodium falciparum DHOD, was a poor inhibitor of TgDHOD. TgDHOD
exhibits a lengthy 157-residue N-terminal extension, consistent with a potential
organellar targeting signal. We constructed C-terminally c-myc tagged TgDHODs to
examine subcellular localization of TgDHOD in transgenic parasites expressing
the tagged protein. Using both exogenous and endogenous expression strategies,
anti-myc fluorescence signal colocalized with antibodies against the
mitochondrial marker ATPase. These findings demonstrate that TgDHOD is
associated with the parasite's mitochondrion, revealing this organelle as the
site of orotate production in T. gondii. The TgDHOD gene appears to be essential
because while gene tagging was successful at the TgDHOD gene locus, attempts to
delete the TgDHOD gene were not successful in the KU80 background. Collectively,
our study suggests that TgDHOD is an excellent target for the development of
anti-Toxoplasma drugs. Author information:
(1)Drug Design and Development Research Group, Department of Chemistry, Faculty
of Science, University of Malaya, Malaysia. Electronic address:
[email protected].
(2)Drug Design and Development Research Group, Department of Chemistry, Faculty
of Science, University of Malaya, Malaysia; Aurigene Discovery Technologies
(Malaysia) Sdn. Bhd, Malaysia; School of Pharmacy, International Medical
University, 57000 Kuala Lumpur, Malaysia.
(3)Drug Design and Development Research Group, Department of Chemistry, Faculty
of Science, University of Malaya, Malaysia.
(4)Aurigene Discovery Technologies (India) Ltd, India.
(5)Aurigene Discovery Technologies (Malaysia) Sdn. Bhd, Malaysia.
(6)Drug Design and Development Research Group, Department of Chemistry, Faculty
of Science, University of Malaya, Malaysia; Department of Molecular Medicine,
Faculty of Medicine, University of Malaya, Malaysia. Dihydroorotate dehydrogenase (DHODH) mediates the fourth step of de novo
pyrimidine biosynthesis and is a proven drug target for inducing
immunosuppression in therapy of human disease as well as a rapidly emerging drug
target for treatment of malaria. In Toxoplasma gondii, disruption of the first,
fifth, or sixth step of de novo pyrimidine biosynthesis induced uracil
auxotrophy. However, previous attempts to generate uracil auxotrophy by
genetically deleting the mitochondrion-associated DHODH of T. gondii (TgDHODH)
failed. To further address the essentiality of TgDHODH, mutant gene alleles
deficient in TgDHODH activity were designed to ablate the enzyme activity.
Replacement of the endogenous DHODH gene with catalytically deficient DHODH gene
alleles induced uracil auxotrophy. Catalytically deficient TgDHODH localized to
the mitochondria, and parasites retained mitochondrial membrane potential. These
results show that TgDHODH is essential for the synthesis of pyrimidines and
suggest that TgDHODH is required for a second essential function independent of
its role in pyrimidine biosynthesis. Author information:
(1)Departamento de Síntese de Fármacos, Instituto de Tecnologia em Fármacos,
Farmanguinhos-FIOCRUZ, Rua Sizedo Nabuco 100, Manguinhos, Rio de Janeiro, RJ
21041-250, Brazil; Programa de Pós Graduação em Química, Instituto de Química,
Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
(2)Centro de Pesquisas René Rachou, CPqRR-FIOCRUZ, Belo Horizonte, MG 30190-002,
Brazil; Programa de Pós Graduação em Medicina Molecular, Faculdade de Medicina,
Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
(3)Laboratório de Cristalografia de Proteínas, Faculdade de Ciências
Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Avenida do Café s/n
Monte Alegre, 14040-903 Ribeirão Preto, SP, Brazil.
(4)Programa de Pós Graduação em Química, Instituto de Química, Universidade
Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
(5)Departamento de Síntese de Fármacos, Instituto de Tecnologia em Fármacos,
Farmanguinhos-FIOCRUZ, Rua Sizedo Nabuco 100, Manguinhos, Rio de Janeiro, RJ
21041-250, Brazil.
(6)Grupo de Biofísica Computacional e Modelagem Molecular, Programa de
Computação Científica (PROCC), FIOCRUZ, Av. Brasil 4365, Rio de Janeiro, CEP
21040-360, Brazil.
(7)Centro de Pesquisas René Rachou, CPqRR-FIOCRUZ, Belo Horizonte, MG 30190-002,
Brazil.
(8)Departamento de Síntese de Fármacos, Instituto de Tecnologia em Fármacos,
Farmanguinhos-FIOCRUZ, Rua Sizedo Nabuco 100, Manguinhos, Rio de Janeiro, RJ
21041-250, Brazil; Programa de Pós Graduação em Química, Instituto de Química,
Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil. Electronic
address: [email protected]. Dihydroorotate dehydrogenase (DHODH), in the de novo pyrimidine biosynthetic
pathway, is the fourth enzyme of pyrimidine synthesis and is used to oxidize
dihydroorotate and hence to orotat. We cloned and characterized here the dhod of
silkworms, Bombyx mori. The full-length cDNA sequence of dhod is 1339 bp,
including an open reading frame (ORF) of 1173 bp that encoded a 390 amino acid
protein. And two domains were involved in the Dihydroorotate dehydrogenase amino
acid sequence of silkworms, Bombyx mori (BmDHODH), namely a DHO_dh domain and a
transmembrane domain in N-termina. The silkworm dhod is expressed throughout
development and in nine tissues. Moreover, knockdown of the silkworm dhod gene
reduced cell growth and proliferation through G2/M phase cell cycle arrest.
Similarly, DHODH inhibitor (leflunomide) also reduced cell growth and
proliferation, with a significant decrease of cyclin B and cdk2. DHODH is the
fourth enzyme of pyrimidine synthesis, so we also found that leflunomide can
inhibit, at least in part, the endomitotic DNA replication in silk glands cells.
These findings demonstrate that downregulation of BmDHODH inhibits cell growth
and proliferation in silkworm cells, and the endomitotic DNA replication in silk
gland cells. Human dihydroorotate dehydrogenase (HsDHODH) is a key enzyme of pyrimidine de
novo biosynthesis pathway. It is located on the mitochondrial inner membrane and
contributes to the respiratory chain by shuttling electrons to the ubiquinone
pool. We have discovered ascofuranone (1), a natural compound produced by
Acremonium sclerotigenum, and its derivatives are a potent class of HsDHODH
inhibitors. We conducted a structure-activity relationship study and have
identified functional groups of 1 that are essential for the inhibition of
HsDHODH enzymatic activity. Furthermore, the binding mode of 1 and its
derivatives to HsDHODH was demonstrated by co-crystallographic analysis and we
show that these inhibitors bind at the ubiquinone binding site. In addition, the
cytotoxicities of 1 and its potent derivatives 7, 8, and 9 were studied using
human cultured cancer cells. Interestingly, they showed selective and strong
cytotoxicity to cancer cells cultured under microenvironment (hypoxia and
nutrient-deprived) conditions. The selectivity ratio of 8 under this
microenvironment show the most potent inhibition which was over 1000-fold higher
compared to that under normal culture condition. Our studies suggest that under
microenvironment conditions, cancer cells heavily depend on the pyrimidine de
novo biosynthesis pathway. We also provide the first evidence that 1 and its
derivatives are potential lead candidates for drug development which target the
HsDHODH of cancer cells living under a tumor microenvironment. |
List targets of classical analgesics. | Patient phenotypes in pharmacological pain treatment varies between individuals, which could be partly assigned to their genotypes regarding the targets of classical analgesics (OPRM1, PTGS2) | Opioid receptors are currently classified as mu (mu: mOP), delta (delta: dOP),
kappa (kappa: kOP) with a fourth related non-classical opioid receptor for
nociceptin/orphainin FQ, NOP. Morphine is the current gold standard analgesic
acting at MOP receptors but produces a range of variably troublesome
side-effects, in particular tolerance. There is now good laboratory evidence to
suggest that blocking DOP while activating MOP produces analgesia (or
antinociception) without the development of tolerance. Simultaneous targeting of
MOP and DOP can be accomplished by: (i) co-administering two selective drugs,
(ii) administering one non-selective drug, or (iii) designing a single drug that
specifically targets both receptors; a bivalent ligand. Bivalent ligands
generally contain two active centres or pharmacophores that are variably
separated by a chemical spacer and there are several interesting examples in the
literature. For example linking the MOP agonist oxymorphone to the DOP
antagonist naltrindole produces a MOP/DOP bivalent ligand that should produce
analgesia with reduced tolerance. The type of response/selectivity produced
depends on the pharmacophore combination (e.g. oxymorphone and naltrindole as
above) and the space between them. Production and evaluation of bivalent ligands
is an emerging field in drug design and for anaesthesia, analgesics that are
designed not to be highly selective morphine-like (MOP) ligands represents a new
avenue for the production of useful drugs for chronic (and in particular cancer)
pain. |
Is actin present in the nucleus? | Yes,
The revitalization of research into nuclear actin occurred after it was found that cellular stresses induce the nuclear localization and alter the structure of actin. | We provide evidence for a mechanism of DNA repair that requires nuclear
myosin/actin-dependent contact between homologous chromosomes to prevent
formation of chromosomal rearrangement in human cells. We recently showed that
DNA double strand breaks (DSBs) induced by γ-rays or endonucleases cause
ATM-dependent contact formation between homologous chromosomes at damaged sites
of transcriptionally active chromatin in G0/G1-phase cells. Here, we report that
the mechanism of contact generation between homologous chromosomes also requires
homology-directed repair proteins, including BRCA1, RAD51 and RAD52, and nuclear
myosin/actin-motors. Moreover, inhibition of ATM kinase or deficiency in nuclear
actin polymerization causes carcinogenic RET/PTC chromosome rearrangements after
DSBs induction in human cells. These data suggest that DSBs in transcriptionally
active euchromatin in G0/G1-phase cells are repaired through a mechanism that
requires contact formation between homologous chromosomes and that this
mechanism is mediated by HDR proteins and nuclear myosin/actin motors. DNA double-strand breaks repaired by non-homologous end joining display limited
DNA end-processing and chromosomal mobility. By contrast, double-strand breaks
undergoing homology-directed repair exhibit extensive processing and enhanced
motion. The molecular basis of this movement is unknown. Here, using Xenopus
laevis cell-free extracts and mammalian cells, we establish that nuclear actin,
WASP, and the actin-nucleating ARP2/3 complex are recruited to damaged chromatin
undergoing homology-directed repair. We demonstrate that nuclear actin
polymerization is required for the migration of a subset of double-strand breaks
into discrete sub-nuclear clusters. Actin-driven movements specifically affect
double-strand breaks repaired by homology-directed repair in G2 cell cycle
phase; inhibition of actin nucleation impairs DNA end-processing and
homology-directed repair. By contrast, ARP2/3 is not enriched at double-strand
breaks repaired by non-homologous end joining and does not regulate
non-homologous end joining. Our findings establish that nuclear actin-based
mobility shapes chromatin organization by generating repair domains that are
essential for homology-directed repair in eukaryotic cells. Until recently it was widely accepted that the dynamic cytoskeletal matrix is
exclusive to the cytoplasm of eukaryotes, evolving before the emergence of the
cell nucleus to enable phagocytosis, cell motility and the sophisticated
functioning of the endomembrane system within the cytosol. The discovery of the
existence of a prokaryotic cytoskeleton has changed this picture significantly.
As a result, the idea has taken shape that the appearance of actin occurred in
the very first cell; therefore, the emergence of microfilaments precedes that of
the eukaryotic cytoskeleton. The discovery of nuclear actin opened new
perspective on the field, suggesting that the nuclear activities of actin
reflect the functions of primordial actin-like proteins. In this paper, we
review the recent literature to explore the evolutionary origin of nuclear
actin. We conclude that both ancient and eukaryotic features of the actin world
can be detected in the nucleus today, which supports the idea that the
cytoskeleton attained significant eukaryotic innovations before the tandem
evolution of the cytoskeleton and nucleus occurred. While it is long known that actin is part of the nuclear proteome, its
properties and functions as regulated, functional and dynamically assembled
actin filaments are only recently emerging. Thus, newly uncovered roles for
intranuclear actin filaments are opening new perspectives on how the nucleus and
its genomic content may be organized in particular with regard to a given stage
of the cell cycle. Here, we summarize recent studies on actin filament
polymerization and turnover within the nuclear compartment of mammalian cells.
We emphasize and discuss novel findings, in which transient and dynamic nuclear
actin filaments have been visualized in physiological contexts, and focus on
aspects of signalling mechanisms, chromatin reorganization and DNA repair.
Further, a better understanding of the spatiotemporal control of nuclear
actin-regulating factors in mammalian cells will ultimately provide a more
detailed view on how the nuclear F-actin cytoskeleton contributes to genome
organization and nuclear architecture. While actin was discovered in the nucleus over 50 years ago, research lagged for
decades due to strong skepticism. The revitalization of research into nuclear
actin occurred after it was found that cellular stresses induce the nuclear
localization and alter the structure of actin. These studies provided the first
hints that actin has a nuclear function. Subsequently, it was established that
the nuclear import and export of actin is highly regulated. While the structures
of nuclear actin remain unclear, it can function as monomers, polymers, and even
rods. Furthermore, even within a given structure, distinct pools of nuclear
actin that can be differentially labeled have been identified. Numerous
mechanistic studies have uncovered an array of functions for nuclear actin. It
regulates the activity of RNA polymerases, as well as specific transcription
factors. Actin also modulates the activity of several chromatin remodeling
complexes and histone deacetylases, to ultimately impinge on transcriptional
programing and DNA damage repair. Further, nuclear actin mediates chromatin
movement and organization. It has roles in meiosis and mitosis, and these
functions may be functionally conserved from ancient bacterial actin homologs.
The structure and integrity of the nuclear envelope and sub-nuclear compartments
are also regulated by nuclear actin. Furthermore, nuclear actin contributes to
human diseases like cancer, neurodegeneration, and myopathies. Here, we explore
the early discovery of actin in the nucleus and discuss the forms and functions
of nuclear actin in both normal and disease contexts. Anat Rec, 301:1999-2013,
2018. © 2018 Wiley Periodicals, Inc. |
What is the indication for KYMRIAH? | Kymriah™ has been approved for the treatment of pediatric patients and young adults with refractory or relapse (R/R) B cell precursor acute lymphoblastic leukemia. | Two autologous chimeric antigen receptor (CAR) T cell therapies (Kymriah™ and
Yescarta™) were recently approved by the FDA. Kymriah™ is for the treatment of
pediatric patients and young adults with refractory or relapse (R/R) B cell
precursor acute lymphoblastic leukemia and Yescarta™ is for the treatment of
adult patients with R/R large B cell lymphoma. In common, both are CD19-specific
CAR T cell therapies lysing CD19-positive targets. Their dramatic efficacy in
the short term has been highlighted by many media reports. By contrast, their
glaring safety gaps behind the miracles remain much less addressed. Here, we
focus on addressing the crucial challenges in relation to the gaps. |
What is the effect of NFIA on astrocyte differentiation? | NFIA promotes astrocyte differentiation from neural precursor cells. | Author information:
(1)Institute of Physiological Chemistry, University Medical Center Johannes
Gutenberg University Mainz, 55128 Mainz, Germany.
(2)Institute of Molecular Biology (IMB), 55128 Mainz, Germany.
(3)Institute of Molecular Biology (IMB), 55128 Mainz, Germany; Broad Institute
of MIT and Harvard, Cambridge, MA, USA; Department of Stem Cell and Regenerative
Biology, Harvard University, Cambridge, MA, USA.
(4)Instituto Cajal, CSIC, Madrid, Spain.
(5)Institute of Molecular Biology (IMB), 55128 Mainz, Germany; Focus Program
Translational Neuroscience, Johannes Gutenberg University Mainz, 55131 Mainz,
Germany. Electronic address: [email protected].
(6)Institute of Physiological Chemistry, University Medical Center Johannes
Gutenberg University Mainz, 55128 Mainz, Germany; Focus Program Translational
Neuroscience, Johannes Gutenberg University Mainz, 55131 Mainz, Germany; Centre
for Developmental Neurobiology, Institute of Psychiatry, Psychology &
Neuroscience, King's College London, London SE1 1UL, UK; MRC Centre for
Neurodevelopmental Disorders, Institute of Psychiatry, Psychology &
Neuroscience, King's College London, London SE1 1UL, UK. Electronic address:
[email protected]. |
What is the mode of action for Tocilizumab? | Tocilizumab (TCZ) is a recombinant humanized monoclonal antibody against the IL-6 receptor and has been approved in many countries, including the United States, for the treatment of moderate to severe RA in patients who have not adequately responded to one or more disease-modifying antirheumatic drugs | Tocilizumab is a recombit humanized antihuman interleukin-6 receptor
monoclonal antibody, which inhibits binding of IL-6 to its soluble (sIL-6R) and
membrane-expressed (mIL-6R) receptors. The work investigated whether the
observed decline in peripheral neutrophil and platelet counts after tocilizumab
administration can be directly explained by tocilizumab IL-6R blockade, thus
demonstrating the mechanism of tocilizumab action. Tocilizumab and total sIL-6R
concentrations, neutrophil and platelet counts from 4 phase 3 studies in
rheumatoid arthritis patients were available. Patients received 4 or 8 mg/kg
tocilizumab intravenous infusions every 4 weeks for a total of 6 doses. A
population approach was applied to describe the relationship between tocilizumab
and sIL-6R concentrations and subsequent changes in neutrophil and platelet
counts. Following tocilizumab administration, concentrations of total sIL-6R
increased, while neutrophil and platelet counts declined. These changes were
transient, with counts returning to their respective baseline levels soon after
tocilizumab is eliminated from the body. Tocilizumab concentrations were
described by a two compartment model with parallel linear and Michaelis-Menten
elimination. The quasi-steady-state target-mediated drug disposition model
described tocilizumab relationships to total sIL-6R, which allowed computation
of unobserved unbound sIL-6R concentrations. The neutrophil counts were
described as a direct function of unbound sIL-6R concentrations. The platelet
counts were described by the transit-compartment life-span model with inhibition
of production that depended on the unbound sIL-6R concentrations. Thus, the
observed changes in sIL-6R, neutrophil, and platelet data are consistent with
the tocilizumab mechanism of action and can be fully explained by tocilizumab
binding to sIL-6R and mIL-6R. Rheumatoid arthritis (RA) is a systemic inflammatory disease characterized by
joint pain, swelling, stiffness, and progressive destruction of the small joints
of the hands and feet. Treatment of RA has improved over the past decade. With
multiple cytokines well-known now to play a role in the pathogenesis of RA,
including tumor necrosis factor alpha, interleukin (IL)-1β, and IL-6, many
targeted biological treatments against these cytokines have emerged, changing
the treatment of this disease. Tocilizumab (TCZ) is a recombit humanized
monoclonal antibody against the IL-6 receptor and has been approved in many
countries, including the United States, for the treatment of moderate to severe
RA in patients who have not adequately responded to one or more
disease-modifying antirheumatic drugs (DMARDs) or cannot tolerate other approved
drug classes for RA. The aim of this review is to discuss the role of IL-6 in
RA, and to provide an overview of the mode of action, pharmacokinetics, and
safety of TCZ. Furthermore, efficacy studies of TCZ as both monotherapy and
combination therapy will be evaluated. There have been several important
clinical trials evaluating the efficacy and safety of TCZ in RA patients; this
review summarizes this data from 14 key trials with emphasis on Phase III
trials. Review of these trials provides strong evidence that its use, both as
monotherapy and in combination with methotrexate or other DMARDs, is an
effective treatment in reducing the signs and symptoms of RA. TCZ showed
tolerable safety but care is required for its use since there are some important
safety concerns including elevated liver enzymes, elevated low-density
lipoprotein, infections, and gastrointestinal perforations. Additionally, given
the efficacy of TCZ in the treatment of RA, this review discusses how TCZ may be
beneficial in the treatment of other autoimmune diseases, spinal disease,
cardiovascular disease, organ transplantation, and maligcies where elevated
levels of IL-6 may play a role in the pathogenesis of these diseases. Interleukin (IL)-6 has a variety of biological functions. For example, it
stimulates the production of acute-phase reactants (C-reactive protein and serum
amyloid A) and hepcidin which interferes with iron recycling and absorption,
causing iron-deficient anemia, and augments expression of vascular endothelial
growth factor and receptor activator of nuclear factor-κB ligand in synovial
cells, leading to neovascularization and osteoclast formation. IL-6 also acts on
lymphocytes, not only on B cells to stimulate autoantibody production, but also
on naïve T helper cells to promote Th17 cell differentiation. Thus, an imbalance
between T cell subsets possibly contributes to development of rheumatoid
arthritis. Several clinical studies have demonstrated that a humanized anti-IL-6
receptor antibody, tocilizumab, improves clinical symptoms in rheumatoid
arthritis. Tocilizumab prevented radiographic progression of joint destruction
by inhibiting cartilage/bone resorption. Tocilizumab also improved hematological
abnormalities, including hypergammaglobulinemia, high levels of autoantibodies,
and elevation of erythrocyte sedimentation rate and acute-phase proteins.
Importantly, tocilizumab improved quality of life by reducing systemic symptoms,
including fatigue, anemia, anorexia, and fever. These findings have confirmed
that hyperproduction of IL-6 is responsible for the above clinical symptoms,
including joint destruction. Many patients treated with tocilizumab achieved
clinical remission associated with decreased serum IL-6, suggesting that IL-6
enhances autoimmunity. Tocilizumab is a new therapeutic option for rheumatoid
arthritis. |
Where is the protein protamine 2 expressed? | Human sperm express two types of protamine: protamine 1 (P1) and the family of protamine 2 (P2) proteins. | Ectopic autografting of testis tissue is a promising approach for studying
testicular development, male germline preservation and restoration of male
fertility. In this study, we examined the fate of various testicular cells in
adult mouse testes following ectopic autografting at 1, 2, 4 and 8 weeks post
grafting. Histological examination showed no evidence of re-establishment of
spermatogenesis in autografts, and progressive degeneration of seminiferous
tubules was detected. Expression of germ cell-specific proteins such as POU5F1,
DAZL, TNP1, TNP2, PRM1 and PRM2 revealed that, although proliferating and
differentiating spermatogenic germ cells such as spermatogonia, spermatocytes
and spermatids could survive in autografts until 4 weeks, only terminally
differentiated germ cells such as sperm persisted in autografts until 8 weeks.
The presence of Sertoli and peritubular myoid cells, as indicated by expression
of WT1 and ACTA2 proteins, respectively, was evident in the autografts until 8
weeks. Interestingly, seminal vesicle weight and serum testosterone level were
restored in autografted mice by 8 weeks post grafting. The expression of Leydig
cell-specific proteins such as CYP11A1, HSD3B2 and LHCGR showed revival of
Leydig cell (LC) populations in autografts over time since grafting. Elevated
expression of PDGFRA, LIF, DHH and NEFH in autografts indicated de novo
regeneration of LC populations. Autografted adult testis can be used as a model
for investigating Leydig cell regeneration, steroidogenesis and regulation of
the intrinsic factors involved in Leydig cell development. The success of this
rodent model can have therapeutic applications for adult human males undergoing
sterilizing cancer therapy. BACKGROUND: Protamines are sperm nuclear proteins with a crucial role in
chromatin condensation. Their function is strongly linked to sperm head
morphology and male fertility. Protamines appear to be affected by a complex
pattern of selective constraints. Previous studies showed that sexual selection
affects protamine coding sequence and expression in rodents. Here we analyze
selective constraints and post-copulatory sexual selection acting on protamine 2
(Prm2) gene sequences of 53 species of primates and rodents. We focused on
possible differences in selective constraints between these two clades and on
the two functional domains of PRM2 (cleaved- and mature-PRM2). We also assessed
if and how changes in Prm2 coding sequence may affect sperm head dimensions.
RESULTS: The domain of Prm2 that is cleaved off during binding to DNA
(cleaved-Prm2) was found to be under purifying selection in both clades, whereas
the domain that remains bound to DNA (mature-Prm2) was found to be positively
selected in primates and under relaxed constraint in rodents. Changes in
cleaved-Prm2 coding sequence are significantly correlated to sperm head width
and elongation in rodents. Contrary to expectations, a significant effect of
sexual selection was not found on either domain or clade.
CONCLUSIONS: Mature-PRM2 may be free to evolve under less constraint due to the
existence of PRM1 as a more conserved and functionally redundant copy. The
cleaved-PRM2 domain seems to play an important role in sperm head shaping.
However, sexual selection on its sequence may be difficult to detect until it is
identified which sperm head phenotype (shape and size) confers advantages for
sperm performance in different mammalian clades. This work aimed at investigating the effect of resveratrol on (1) DNA integrity
and (2) fertilizing capacity of sperm by quantifying the presence of key
paternal transcripts considered as markers for male fertility (protamine 1
[PRM1] and protamine 2 [PRM2]) and pregcy success (adducin 1 alpha [ADD1]) in
cryopreserved human spermatozoa through modulation of AMP-activated protein
kinase (AMPK). The study populations was drawn from 22 normozoospermic healthy
volunteers which were incubated with or without AMPK activator (resveratrol
[RSV], 15 µM) or inhibitor (Compound C [CC], 30 µM) for 1 h and were then
cryopreserved. Untreated frozen-thawed spermatozoa served as controls. The
RSV-induced AMPK activation decreased the level of DNA fragmentation in
comparison with the control (21.18 ± 0.92 vs. 22.50 ± 0.40; p < 0.01). The
relative mRNA expression levels of protamines (1 and 2) and ADD1 in RSV
pretreated frozen-thawed human spermatozoa were also improved significantly
compared to the control (p < 0.05). Conversely, the inhibitory effect of CC on
AMPK activity deteriorated the deleterious effects of cryopreservation on these
parameters (p < 0.01). In conclusion, these results demonstrated the
cryoprotective effect of the RSV-induced increase in AMPK activity on DNA
integrity and key paternal transcripts of cryopreserved human spermatozoa. These
findings are of great importance for improving the available cryopreservation
protocols in terms of the number of lesions that produced over key genes and the
dramatic effects on sperm DNA fragmentation. |
Can miR-122 target RUNX2? | Yes, miR-122 directly targets RUNX2. | OBJECTIVE: Accumulating evidence has suggested that microRNAs play critical
roles in the development and progression of human glioma. The role of miR-122 in
glioma tumorigenesis has been poorly defined. The current study is designed to
investigate whether and how miR-122 affects proliferation and apoptosis of human
glioma cells.
PATIENTS AND METHODS: 8 normal brain tissues and 19 glioma tissues (7 for low
grade and 12 for high grade) were collected. The expressions of miR-122 and
runt-related transcription factors (RUNX2) in normal brain/glioma tissues and
normal astrocytes (NHA)/multiple glioma cell lines (U87, U251, and U118) were
analyzed by Real-time polymerase chain reaction (PCR). Western blot and
luciferase activity assays were performed to validate the predicted relationship
between miR-122 and RUNX2. The effects of miR-122 on cell proliferation and
apoptosis were assessed by cell counting kit-8 (CCK-8), colony forming, and
Annexin V-FITC/PI apoptosis assays using both gain- and loss-of-function
approaches.
RESULTS: MiR-122 expression is downregulated in glioma tissues compared with
normal brain tissues, and is negatively correlated with the WHO grade. In
contrast, the RUNX2 expression is upregulated in glioma tissues, and is
positively correlated with the WHO grade. In glioma cell lines, the miR-122
expression is also constantly downregulated. MiR-122 functions as a tumor
suppressor by inhibiting proliferation and inducing apoptosis, which is achieved
by directly targeting RUNX2. Overexpression of RUNX2 can partially abrogate the
effect of miR-122 on glioma cells.
CONCLUSIONS: These results demonstrate a crucial role of miR-122 in regulating
cell proliferation and apoptosis. Identifying the miR-122/RUNX2 signaling
provides novel insights into the development of therapeutic targets for glioma. |
Tocilizumab is an anti-TNF antibody, yes or no? | Tocilizumab (TCZ) is a humanized monoclonal antibody against IL-6 receptor licensed in 2009 | (1) First-line disease-modifying treatment for rheumatoid arthritis is based on
"slow-acting" antirheumatic agents, generally methotrexate. Subsequent options
include a TNF-alpha antagonist, followed by rituximab or possibly abatacept; (2)
Tocilizumab, a monoclonal antibody, inhibits interleukin-6 receptors. It is
licensed in the European Union for patients with rheumatoid arthritis in whom
other drugs have failed; (3) Clinical evaluation includes 4 placebo-controlled
trials of the methotrexate-tocilizumab combination, after failure of a
slow-acting antirheumatic drug (3 trials) or failure of a slow-acting
antirheumatic drug and a TNF-alpha antagonist (1 trial). An indirect comparison
suggests that tocilizumab is no more effective than rituximab in patients with
multiple treatment failure; (4) Tocilizumab, like TNF-alpha antagonists, is an
immunosuppressant. It carries a risk of serious infections, haematological
disorders (neutropenia, thrombocytopenia), gastrointestinal bleeding, hepatic
disorders, and systemic and local reactions during the infusion; (5) the adverse
effects of long-term tocilizumab therapy are unknown, particularly the risk of
cancer; (6) Tocilizumab carries a risk of interactions with drugs that are
metabolised by cytochrome P450 isoenzymes. Clinical consequences cannot be ruled
out when co-administered drugs have a narrow therapeutic margin; (7) Tocilizumab
is administered intravenously every 4 weeks, making it slightly more convenient
that rituximab at the beginning of treatment; (8) In patients with rheumatoid
arthritis and multiple treatment failure, it remains to be shown whether
tocilizumab has a better risk-benefit balance than rituximab, a drug with which
we have more experience. It is therefore better to continue to use rituximab, or
possibly abatacept. Tocilizumab is a humanized anti-IL-6 receptor monoclonal antibody, which binds
to circulating soluble IL-6 receptor and membrane-expressed IL-6 receptor,
inhibiting IL-6 binding to both forms of IL-6 receptor. Several Phase III
clinical trials demonstrate the clinical efficacy of tocilizumab as monotherapy
or with disease-modifying anti-rheumatic drugs for adult patients with
moderately to severely active rheumatoid arthritis. Tocilizumab in combination
with methotrexate after 24 weeks of treatment could induce disease remission in
30% of patients with rheumatoid arthritis refractory to anti-TNF antagonist
therapy. The most common adverse reactions reported in clinical studies are
upper respiratory tract infection, nasopharyngitis, headache, hypertension and
mild, reversible increases in alanine aminotransferase enzymes. Serious adverse
reactions include infections, gastrointestinal perforations and hypersensitivity
reactions, including anaphylaxis. The clinical efficacy and safety of
tocilizumab has led to the approval of this innovative drug for the treatment of
rheumatoid arthritis in more than 70 countries worldwide. Recent years have seen many exciting developments in the treatment of rheumatoid
arthritis. Tocilizumab (TCZ) is a monoclonal antibody which inhibits the
interleukin-6 receptor. After initial studies in Japan, it has been extensively
studied in five multicentre clinical trials. This report summarises the key
efficacy and toxicity findings from the major clinical trials. TCZ works quickly
and effectively in rheumatoid arthritis either as monotherapy or in combination
with other agents in early disease, DMARD inadequate responders, seronegative
disease and after anti-TNF failure. The toxicity profile is manageable but
includes infections (most notably skin and soft tissue), increases in serum
cholesterol, transient decreases in neutrophil count and abnormal liver function
tests (especially in combination with methotrexate). In summary, there is
sufficient evidence to make TCZ a first line biologic therapy for rheumatoid
arthritis especially for those who are unable to take methotrexate or who fail
anti-TNF therapy. Rheumatoid arthritis (RA) is a chronic inflammatory arthritis with many systemic
manifestations. Several monoclonal antibodies targeting different components of
the immune systems have been licensed for treatment of RA. Inflammatory
cytokines such as interleukin-6 (IL-6) are found abundantly in the blood and the
joints. The biologic effect of IL-6 on leukocyte, osteoclast, hepatocytes and
bone marrow may mediate the articular and systemic inflammation in RA. Recently,
an anti-IL-6 receptor monoclonal antibody, tocilizumab, has been licensed for
the treatment as monotherapy or in combination with methotrexate of moderate to
severe RA, when disease modifying anti-rheumatic drugs or anti-tumour necrosis
factors (TNF) have failed. It improves symptoms and signs as well as reducing
joint damage. Tocilizumab monotherapy has been shown to be superior to
methotrexate. Its side-effects include infections, decrease in neutrophils, and
increases in lipid and liver transaminases. Overall, tocilizumab has a
well-defined and manageable safety profile that supports a favourable
benefit/risk ratio for patients with RA. Tocilizumab is a monoclonal humanized anti-IL-6-receptor antibody used for the
treatment of rheumatoid arthritis. The safety of tocilizumab in HCV patients is
an open question. We report on safety and efficacy of tocilizumab in a
71-year-old female with rheumatoid arthritis and chronic hepatitis C.
Monotherapy with tocilizumab (8 mg/kg every 4 weeks, i.v.) was prescribed after
the discontinuation, determined by clinical inefficacy, of anti-TNF-alfa agents
(adalimumab and, subsequently, etanercept). We have registered an optimal and
rapid clinical response to tocilizumab with early remission (SDAI <3.3 since 4
weeks). The safety was good with no adverse events and maintece, during a
six-month followup, of normal liver enzymes. These data suggest a good safety
profile of tocilizumab in patients with rheumatoid arthritis and chronic
hepatitis C virus pathology. INTRODUCTION: Anemia of inflammation (AI) is a common complication of rheumatoid
arthritis (RA) and has a negative impact on RA symptoms and quality of life.
Upregulation of hepcidin by inflammatory cytokines has been implicated in AI. In
this study, we evaluated and compared the effects of IL-6 and TNF-α blocking
therapies on anemia, disease activity, and iron-related parameters including
serum hepcidin in RA patients.
METHODS: Patients (n = 93) were treated with an anti-IL-6 receptor antibody
(tocilizumab) or TNF-α inhibitors for 16 weeks. Major disease activity
indicators and iron-related parameters including serum hepcidin-25 were
monitored before and 2, 4, 8, and 16 weeks after the initiation of treatment.
Effects of tocilizumab and infliximab (anti-TNF-α antibody) on cytokine-induced
hepcidin expression in hepatoma cells were analyzed by quantitative real-time
PCR.
RESULTS: Anemia at base line was present in 66% of patients. Baseline serum
hepcidin-25 levels were correlated positively with serum ferritin, C-reactive
protein (CRP), vascular endothelial growth factor (VEGF) levels and Disease
Activity Score 28 (DAS28). Significant improvements in anemia and disease
activity, and reductions in serum hepcidin-25 levels were observed within 2
weeks in both groups, and these effects were more pronounced in the tocilizumab
group than in the TNF-α inhibitors group. Serum hepcidin-25 reduction by the
TNF-α inhibitor therapy was accompanied by a decrease in serum IL-6, suggesting
that the effect of TNF-α on the induction of hepcidin-25 was indirect. In in
vitro experiments, stimulation with the cytokine combination of IL-6+TNF-α
induced weaker hepcidin expression than did with IL-6 alone, and this induction
was completely suppressed by tocilizumab but not by infliximab.
CONCLUSIONS: Hepcidin-mediated iron metabolism may contribute to the
pathogenesis of RA-related anemia. In our cohort, tocilizumab was more effective
than TNF-α inhibitors for improving anemia and normalizing iron metabolism in RA
patients by inhibiting hepcidin production. The recent development of biological agents, namely, anti-tumour necrosis factor
alpha (TNF-α) agents (infliximab, adalimumab and etanercept), anti- CD20
monoclonal antibody (rituximab) and anti-interleukin 6 receptor (IL-6R)
monoclonal antibody (tocilizumab), represents a major breakthrough for the
treatment of immune-mediated disorders. Given their structural and functional
differences, distinct safety profiles can be expected for each of these agents.
Evidence in the literature indicates that patients treated with anti-TNF-α
agents and tocilizumab are at increased risk for bacterial infections. However,
an increased therapeutic use of these biological agents has disclosed other
side-effects, including immediate hypersensitivity reactions, such as
anaphylaxis and urticaria. Both under-diagnosis and over-diagnosis of
hypersensitivity reactions to biological agents are potential problems. Thus, it
is important to identify these reactions and to adopt the right approach to
manage them. This article reviews the general aspects of adverse events during
biologic treatment, focusing on IgE-mediated hypersensitivity reactions to
anti-TNF-α agents, rituximab and tocilizumab, and on the tools for the diagnosis
of these life-threatening reactions. Castleman disease is a rare lymphoproliferative disorder with 2 distinctly
defined clinical forms. While multicentric Castleman disease (UCD) poses a
potential therapeutic challenge, unicentric variant has historically been
considered curable with surgical resection. Hence, little is known to guide
management of patients with UCD, refractory to surgical resection and
combination chemotherapy. We present a case of a patient, negative for HIV and
HHV-8, who had an unsuccessful surgical intervention and no response to
radiotherapy and chemotherapy. He had severe paraneoplastic pemphigus and was
treated with tocilizumab, an anti-interleukin-6 receptor monoclonal antibody
that has demonstrated good response rates in multicentric Castleman disease but
demonstrated no clinical response despite 2 months of treatment. Our report is
the first to describe a lack of response to tocilizumab in the rare setting of
refractory UCD and discuss potential for distinct disease biology. Rheumatoid arthritis (RA) is the most prevalent immune-mediated chronic
rheumatic disease and is associated with joint destruction and disability.
Therapeutic strategies, including biological disease-modifying antirheumatic
drugs (bDMARDs) have improved the prognosis and quality of life of RA patients.
Tocilizumab (TCZ) is a humanized monoclonal antibody against IL-6 receptor
licensed in 2009 that has demonstrated clinical efficacy in various adult RA
populations. RA management guidelines and recommendations consider TCZ as one of
the bDMARDS indicated after methotrexate or other conventional synthetic DMARDs
and/or TNF inhibitors failure in adult RA. Of particular interest is the
demonstration of its effectiveness in monotherapy in comparison with other
bDMARDs. Recent observational studies have shown good results for the safety
profile of TCZ with no new alert signals. |
Is it possible to analyze exosomes with FACS? | Yes,
a novel strategy for generating metabolically-labeled fluorescent exosomes that can be counted by flow cytometry assay (FACS) and characterized. | Plasma-derived vesicles hold a promising potential for use in biomedical
applications. Two major challenges, however, hinder their implementation into
translational tools: (a) the incomplete characterization of the protein
composition of plasma-derived vesicles, in the size range of exosomes, as mass
spectrometric analysis of plasma sub-components is recognizably troublesome and
(b) the limited reach of vesicle-based studies in settings where the
infrastructural demand of ultracentrifugation, the most widely used
isolation/purification methodology, is not available. In this study, we have
addressed both challenges by carrying-out mass spectrometry (MS) analyses of
plasma-derived vesicles, in the size range of exosomes, from healthy donors
obtained by 2 alternative methodologies: size-exclusion chromatography (SEC) on
sepharose columns and Exo-Spin™. No exosome markers, as opposed to the most
abundant plasma proteins, were detected by Exo-Spin™. In contrast, exosomal
markers were present in the early fractions of SEC where the most abundant
plasma proteins have been largely excluded. Noticeably, after a
cross-comparative analysis of all published studies using MS to characterize
plasma-derived exosomes from healthy individuals, we also observed a paucity of
"classical exosome markers." Independent of the isolation method, however, we
consistently identified 2 proteins, CD5 antigen-like (CD5L) and
galectin-3-binding protein (LGALS3BP), whose presence was validated by a
bead-exosome FACS assay. Altogether, our results support the use of SEC as a
stand-alone methodology to obtain preparations of extracellular vesicles, in the
size range of exosomes, from plasma and suggest the use of CD5L and LGALS3BP as
more suitable markers of plasma-derived vesicles in MS. Author information:
(1)Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità,
Viale Regina Elena 299, 00161 Rome, Italy. [email protected].
(2)Department of Neurosciences, Istituto Superiore di Sanità, Viale Regina Elena
299, 00161 Rome, Italy. [email protected].
(3)National Center for Global Health, Istituto Superiore di Sanità, Viale Regina
Elena 299, 00161 Rome, Italy. [email protected].
(4)National Center for Global Health, Istituto Superiore di Sanità, Viale Regina
Elena 299, 00161 Rome, Italy. [email protected].
(5)National Center for Global Health, Istituto Superiore di Sanità, Viale Regina
Elena 299, 00161 Rome, Italy. [email protected].
(6)National Center for Global Health, Istituto Superiore di Sanità, Viale Regina
Elena 299, 00161 Rome, Italy. [email protected].
(7)National Center for Global Health, Istituto Superiore di Sanità, Viale Regina
Elena 299, 00161 Rome, Italy. [email protected].
(8)Core Facilities⁻Cytometry Unit, Istituto Superiore di Sanità, Viale Regina
Elena 299, 00161 Rome, Italy. [email protected].
(9)National AIDS Center, Istituto Superiore di Sanità, Viale Regina Elena 299,
00161 Rome, Italy. [email protected].
(10)Core Facilities⁻Cytometry Unit, Istituto Superiore di Sanità, Viale Regina
Elena 299, 00161 Rome, Italy. [email protected].
(11)National Center for Global Health, Istituto Superiore di Sanità, Viale
Regina Elena 299, 00161 Rome, Italy. [email protected].
(12)National Center for Global Health, Istituto Superiore di Sanità, Viale
Regina Elena 299, 00161 Rome, Italy. [email protected]. BACKGROUND: Microenvironment cues involved in melanoma progression are largely
unknown. Melanoma is highly influenced in its aggressive phenotype by the
changes it determinates in its microenvironment, such as pH decrease, in turn
influencing cancer cell invasiveness, progression and tissue remodelling through
an abundant secretion of exosomes, dictating cancer strategy to the whole host.
A role of exosomes in driving melanoma progression under microenvironmental
acidity was never described.
METHODS: We studied four differently staged human melanoma lines, reflecting
melanoma progression, under microenvironmental acidic pHs pressure ranging
between pH 6.0-6.7. To estimate exosome secretion as a function of tumor stage
and environmental pH, we applied a technique to generate native fluorescent
exosomes characterized by vesicles integrity, size, density, markers expression,
and quantifiable by direct FACS analysis. Functional roles of exosomes were
tested in migration and invasion tests. Then we performed a comparative
proteomic analysis of acid versus control exosomes to elucidate a specific
signature involved in melanoma progression.
RESULTS: We found that metastatic melanoma secretes a higher exosome amount than
primary melanoma, and that acidic pH increases exosome secretion when melanoma
is in an intermediate stage, i.e. metastatic non-invasive. We were thus able to
show that acidic pH influences the intercellular cross-talk mediated by
exosomes. In fact when exposed to exosomes produced in an acidic medium, pH
naïve melanoma cells acquire migratory and invasive capacities likely due to
transfer of metastatic exosomal proteins, favoring cell motility and
angiogenesis. A Prognoscan-based meta-analysis study of proteins enriched in
acidic exosomes, identified 11 genes (HRAS, GANAB, CFL2, HSP90B1, HSP90AB1, GSN,
HSPA1L, NRAS, HSPA5, TIMP3, HYOU1), significantly correlating with poor
prognosis, whose high expression was in part confirmed in bioptic samples of
lymph node metastases.
CONCLUSIONS: A crucial step of melanoma progression does occur at melanoma
intermediate -stage, when extracellular acidic pH induces an abundant release
and intra-tumoral uptake of exosomes. Such exosomes are endowed with
pro-invasive molecules of clinical relevance, which may provide a signature of
melanoma advancement. |
Which company developed opdivo? | Opdivo or nivolumab was developed by Bristol-Myers Squibb. | As part of its single technology appraisal (STA) process, the National Institute
for Health and Care Excellence (NICE) invited the manufacturer (Bristol-Myers
Squibb) of nivolumab (Opdivo®) to submit evidence of its clinical and cost
effectiveness for metastatic or unresectable urothelial cancer. Kleijnen
Systematic Reviews Ltd, in collaboration with Maastricht University Medical
Centre+, was commissioned to act as the independent Evidence Review Group (ERG),
which produced a detailed review of the evidence for the clinical and cost
effectiveness of the technology, based on the company's submission to NICE.
Nivolumab was compared with docetaxel, paclitaxel, best supportive care and
retreatment with platinum-based chemotherapy (cisplatin plus gemcitabine, but
only for patients whose disease has had an adequate response in first-line
treatment). Two ongoing, phase I/II, single-arm studies for nivolumab were
identified, but no studies directly compared nivolumab with any specified
comparator. Evidence from directly examining the single arms of the trial data
indicated little difference between the outcomes measured from the nivolumab and
comparator studies. A simulated treatment comparison (STC) analysis was used in
an attempt to reduce the bias induced by naïve comparison, but there was no
clear evidence that risk of bias was reduced. Multiple limitations in the STC
were identified and remained. The effect of an analysis based on different
combinations of covariates in the prediction model remains unknown. The ERG's
concerns regarding the economic analysis included the use of a non-established
response-based survival analysis method, which introduced additional
uncertainty. The use of time-dependent hazard ratios produced overfitting and
was not represented in the probabilistic sensitivity analysis. The use of a
treatment stopping rule to cap treatment cost left treatment effectiveness
unaltered. A relevant comparator was excluded from the base-case analysis. The
revised ERG deterministic base-case incremental cost-effectiveness ratios based
on the company's Appraisal Consultation Document response were £58,791, £78,869
and £62,352 per quality-adjusted life-year gained versus paclitaxel, docetaxel
and best supportive care, respectively. Nivolumab was dominated by cisplatin
plus gemcitabine in the ERG base case. Substantial uncertainties about the
relative treatment effectiveness comparing nivolumab against all comparators
remained. NICE did not recommend nivolumab, within its marketing authorisation,
as an option for treating locally advanced, unresectable or metastatic
urothelial carcinoma in adults who have had platinum-containing therapy, and
considered that nivolumab was not suitable for use within the Cancer Drugs Fund. |
What are DMARDs? | To determine the utility of ultrasonography in guiding modification of disease-modifying anti-rheumatic drug (DMARD) and steroid therapy for inflammatory arthritis (IA) | Disease-modifying antirheumatic drug (DMARD) therapy is now clearly accepted as
the primary treatment for rheumatoid arthritis, with an increasing emphasis on
use of combination therapy. Data on combination therapy have highlighted the
difficulties in performing these studies and the large number of patients
required to produce meaningful results. Combination studies have focused on use
of rapidly decreasing high-dose steroids as a part of the combination and
emphasize the importance of using patients with early rheumatoid arthritis. Even
with relatively aggressive use of DMARDs, the majority of patients develop
erosions. Adverse reactions to DMARDs continue to concern clinicians, although
evaluation of the frequency of these events has led to a reappraisal of
previously accepted monitoring strategies in some cases. For example, it may not
be cost-effective to subject patients on antimalarials to regular review by an
ophthalmologist because of the low frequency of serious eye defects. Studies
have also identified risk factors for the development of pulmonary toxicity in
association with methotrexate. That DMARDs are effective in treating rheumatoid
arthritis is beyond question-just how effective they are and what combinations
of DMARDs will show improved efficacy will provide data for the next annual
review. BACKGROUND: Therapy of rheumatoid arthritis (RA) is typically characterized by
the sequential use of disease-modifying anti-rheumatic drugs (DMARDs). This
study aimed to reveal treatment patterns with traditional DMARDs and their
changes during the two decades before the recent introduction of new DMARDs.
METHODS: A total of 593 RA patients were followed from their first presentation
to our clinic throughout the course of their disease; 222 patients received
their first DMARD therapy while under our care. More than 2,300 patient years of
therapy were analysed for the efficacy [using C-reactive protein (CRP) and
erythrocyte sedimentation rate (ESR) as surrogates] and duration of drug therapy
of consecutive DMARDs.
RESULTS: Before 1985, 65-90% of initial DMARDs were gold compounds, but their
use decreased continuously thereafter. Antimalarial (AM) drugs were important
initial DMARDs in new patients at all times, whereas sulphasalazine (SSZ) and
methotrexate (MTX) gained increasing significance after 1985 (the first DMARD
was MTX in up to 29% of new patients). Penicillamine (DPA), azathioprine (AZP),
cyclosporin (CyA) and combination therapies were not usually employed initially,
but were reserved for the later course of the disease. Gender, age and
rheumatoid factor were not different between patients receiving different
DMARDs. The baseline acute-phase response was higher in patients treated with
MTX (mean CRP 3.5 mg/dl) than in those treated with SSZ (CRP 2.4 mg/dl; P <
0.05) or AM (CRP 2.1 mg/dl; P < 0.05), suggesting that MTX was used
preferentially in patients with high disease activity. On the other hand, once
AM or SSZ had been discontinued, MTX was the most common subsequent DMARD (in 31
and 56% respectively). Comparison of first DMARDs with subsequent ones revealed
that first DMARDs were more effective: the acute-phase response decreased most
prominently during first therapies (CRP reduction was 1.28 mg/dl during first
courses and 0.35 mg/dl during fourth or later courses; P < 0.01); and retention
rates were significantly longer for first compared with subsequent therapies
(median of 24.5 months for first and 18.6 months for fourth or subsequent
therapies; P < 0.001).
CONCLUSION: MTX was the most commonly employed DMARD therapy for RA and was used
increasingly as first therapy in newly diagnosed RA. Patients with high disease
activity were given MTX therapy more often than other DMARDs, while those with
low activity were more likely to receive SSZ or AM, and MTX on failure of these
drugs. First DMARDs in new patients were retained longer than subsequent DMARDs,
apparently because they are more effective. OBJECTIVES: Patients and rheumatologists have a number of options to consider
for the treatment of rheumatoid arthritis (RA), including biologic response
modifier (BRM) therapy and diseasemodifying antirheumatic drugs (DMARDs). The
objective of this study was to identify the considerations that are most
important to patients and rheumatologists when deciding to initiate BRM therapy
for RA.
METHODS: An online survey was conducted by Harris Interactive (Rochester, NY)
and completed in January 2007. Patients receiving BRMs were asked to rank their
considerations in initiating BRM therapy, patients receiving DMARDs were asked
to rank their considerations in switching to or initiating BRM therapy, and
rheumatologists were asked to rank their considerations in prescribing BRM
therapy. Participants arranged the following 9 factors from most to least
important: efficacy, safety/side effects, years on market, physician's
experience with product, physician's personal preference, method of
administration, dosing frequency, cost (out of pocket), and patient support
programs.
RESULTS: A total of 400 rheumatologists and 729 patients were surveyed (BRMs, n
= 504; DMARDs, n = 225). The following factors were ranked consistently high
across groups: safety (ranked first, first, and second for BRM patients, DMARD
patients, and rheumatologists, respectively), efficacy (second, fourth, and
first, respectively), and physician's experience with the drug (third for all 3
groups). Years on market (ranked seventh, sixth, and seventh, respectively) and
availability of patient support groups ranked consistently low.
CONCLUSIONS: When considering BRM therapy for RA, the 3 most important factors
for patients and physicians are safety, efficacy, and the physician's experience
with the product. The primary goal in the treatment of rheumatoid arthritis (RA) is to maintain
good quality of life by preventing joint destruction and avoiding disability.
For this purpose, all patients with the diagnosis of RA should be treated by
disease-modifying antirheumatic drugs (DMARDs) including biologic DMARDs and
non-biologic DMARDs. All DMARDs are expected to prevent the progression of bone
and cartilage destruction of RA patients from the results of in vitro research,
and prevention of joint destruction is confirmed in vivo in all biologic DMARDs,
but not in all non-biologic DMARDs. In this chapter, we would like to review the
results of basic researches and clinical studies to demonstrate the prevention
of joint destruction by non-biologic DMARDs that have been frequently used I
daily practice. BACKGROUND: Treatment of juvenile idiopathic arthritis (JIA) with
disease-modifying antirheumatic drugs (DMARDs) may improve outcomes compared to
conventional therapy (e.g., non-steroidal anti-inflammatory drugs,
intra-articular corticosteroids). The purpose of this systematic review was to
evaluate the comparative effectiveness and safety of DMARDs versus conventional
therapy and versus other DMARDs.
RESULTS: A systematic evidence review of 156 reports identified in MEDLINE®,
EMBASE®, and by hand searches. There is some evidence that methotrexate is
superior to conventional therapy. Among children who have responded to a
biologic DMARD, randomized discontinuation trials suggest that continued
treatment decreases the risk of having a flare. However, these studies evaluated
DMARDs with different mechanisms of action (abatacept, adalimumab, anakinra,
etanercept, intravenous immunoglobulin, tocilizumab) and used varying
comparators and follow-up periods. Rates of serious adverse events are similar
between DMARDs and placebo in published trials. This review identified 11
incident cases of cancer among several thousand children treated with one or
more DMARD.
CONCLUSIONS: Few data are available to evaluate the comparative effectiveness of
either specific DMARDs or general classes of DMARDs. However, based on the
overall number, quality, and consistency of studies, there is moderate strength
of evidence to support that DMARDs improve JIA-associated symptoms. Limited data
suggest that short-term risk of cancer is low. OBJECTIVES: When rheumatoid arthritis (RA) patients have achieved sustained good
clinical responses can their disease-modifying anti-rheumatic drugs (DMARDs) be
reduced or discontinued? This review addresses this question by summarising the
clinical evidence about DMARD withdrawal. It includes an assessment of
predictive factors for sustained DMARD-free remissions.
METHODS: We evaluated the evidence for discontinuing DMARDs in stable RA in both
randomised controlled trials (RCTs) and observational studies.
RESULTS: Six RCTs evaluated DMARD monotherapy withdrawal in 501 RA patients with
good clinical responses. Flares occurred in 43/248 (17%) patients who continued
DMARD monotherapy and in 117/253 (46%) patients who discontinued DMARDs.
Individuals in whom DMARDs were withdrawn were three times more likely to have
flares. Restarting DMARDs post-flare was usually successful. Four RCTs evaluated
step-down DMARD combinations in comparison to DMARD monotherapy. Patients
achieved good clinical responses with combination DMARDs, which were maintained
after treatment was tapered to DMARD monotherapy. Four observational studies of
tapering or stopping DMARDs in patients with sustained low disease activity
states provided supportive evidence for discontinuing DMARDs in some patients.
Flares during drug-free remissions were predicted by rheumatoid factor and
anti-citrullinated protein antibody status.
CONCLUSIONS: Drug-free remission is achievable in some RA patients.
Discontinuation of DMARDs after patients achieve sustained remissions results in
flares in many patients, which can usually be reversed by restarting DMARDs.
Step-down DMARD combinations are effective and achieve sustained responses.
Further research is required to establish predictors of drug-free remission;
these will identify individuals most likely to benefit or experience disease
flares after discontinuing DMARDs. OBJECTIVE: Disease-modifying antirheumatic drugs (DMARDs) are the standard of
care for rheumatoid arthritis (RA); however, studies have found that many
patients do not receive them. We examined predictors of starting and stopping
DMARDs among a longitudinal cohort of patients with RA.
METHODS: Study participants came from a cohort of RA patients recruited from a
random sample of rheumatologists' practices in Northern California. We examined
patterns and predictors of stopping and starting nonbiologic and biologic DMARDs
during 1982-2009 based on annual questionnaires. Stopping was defined as
stopping all DMARDs and starting was defined as transitioning from no DMARDs to
any DMARDs across 2 consecutive years.
RESULTS: The analysis of starting DMARDs included 471 subjects with 1,974 pairs
of years with no DMARD use in the first of 2 consecutive years. From this
population, subjects started DMARD use by year 2 in 313 (15.9%) of the pairs.
The analysis of stopping DMARDs included 1,026 subjects with 7,595 pairs of
years with DMARD use in the first of 2 consecutive years; in 423 pairs (5.6%),
subjects stopped DMARD use by year 2. In models that adjusted for RA-related
factors, sociodemographics, and comorbidities, significant predictors of
starting DMARDs included younger age, Hispanic ethnicity, shorter disease
duration, and the use of oral glucocorticoids. In separate adjusted models,
predictors of stopping DMARDs included Hispanic ethnicity and low income, while
younger age was associated with a reduced risk of stopping.
CONCLUSION: Efforts to improve DMARD use should focus on patient age, ethnicity,
and income and RA-related factors. Disease modifying antirheumatic drugs (DMARDs) is a category of drugs which is
used as medication in various arthritic conditions to arrest the progression of
disease along with relief from pain. About 83% of population worldwide uses
DMARDs. Withdrawal of COX-2 inhibitors because of cardiovascular side effects
and short-term action associated with glucocorticoids provided a motivation for
development of newer DMARDs. Currently non- biological DMARDs like methotrexate,
sulfasalazine, hydroxychloroquine and azathioprine serve the purpose of
relieving pain and inhibiting the progression of disease. Biological DMARDs like
toclizumab, adalimumab, infliximab, golimumab and abatacept have shown more
efficacy and lesser side effects as compared to non- biological DMARDs but their
access to patient is less because of higher cost. DMARDs act by different
mechanisms against inflammation like inhibition of tumor necrosis factor,
suppression of IL-1 and TNF-α, induction of apoptosis of inflammatory cells, by
increasing chemotactic factors, inhibition of purine synthesis, pyrimidine
metabolism or purine embolism. DMARDs have important applications in diseases
like rheumatoid arthritis, Crohn's disease, juvenile idiopathic arthritis,
psoriatic arthritis and myasthenia gravis. Present review mainly focuses on
DMARDs and their clinical applications giving an overview of their mechanism of
action, pharmacokinetic properties, advantages over conventional therapies,
shortcomings and recent trends. OBJECTIVE: To explore what considerations patients have when deciding about
disease-modifying antirheumatic drugs (DMARDs) and what information patients
need to participate in the decision-making process.
METHODS: In-depth face-to-face interviews were conducted with 32 patients with
inflammatory arthritis who recently consulted their rheumatologist and discussed
initiating DMARDs.
RESULTS: Beliefs in the necessity of DMARDs, either for relief of symptoms or
prevention of future joint damage, were reasons to initiate DMARDs. Furthermore,
trust in the rheumatologist and the health care system was important in this
respect. Patients expressed many concerns about initiating DMARDS. These related
to the perceived aggressive and harmful nature of DMARDs, potential (or unknown)
side effects, influence on fertility and pregcy, combination with other
medicines, time to benefit, and manner of administration. Participants also
worried about the future regarding long-term medication use and drug dependency,
and if a medicine proved to be ineffective, about the risks of future treatments
and running out of options. To decrease uncertainty, participants wanted to be
informed about multiple treatment options, both current and future. They not
only wanted clinical information but also information on how the medications
could affect their daily lives.
CONCLUSION: Health education should inform patients about multiple treatment
options, for the present as well as for the future. It should enable patients to
compare treatments with regard to both clinical aspects as well as possible
consequences for their daily lives. PURPOSE OF REVIEW: Dramatic improvement seen in the prognosis of rheumatoid
arthritis has been driven by higher expectations, led by newer drugs and more
intensive use of the older drugs. Although methotrexate has retained its place
as the first-line agent, there has been great interest in comparing biologicals
to conventional Disease Modifying Anti Rheumatic Drugs (DMARDs) over the past
few years with the updated guidelines from both the American College of
Rheumatology and European League Against Rheumatism. We have tried to critically
summarize the findings of some landmark trials that compare these two
approaches.
RECENT FINDINGS: Treatment of Early Rheumatoid Arthritis, The Swedish
Pharmacotherapy study and Rheumatoid Arthritis Comparison of Active Therapies
are landmark trials that were designed to compare strategies using biologicals
vs. conventional DMARDs. We will review the safety and efficacy data from these
three trials here and also briefly the important cost differential.
CONCLUSION: Methotrexate should be the first-line therapy for most rheumatoid
arthritis patients and will produce the desired results in greater than
one-third of the patients. When methotrexate is not adequate, triple DMARD
therapy should be added which will result in control of approximately another
one-third of the patients. Ultimately, and usually before 1 year of disease, the
remainder of patients will require biological therapies usually added to
conventional DMARDs. There is no evidence that this step-up approach results in
any long-term disadvantage and good evidence that it results in substantial cost
savings. Tocilizumab (TCZ) and tumour necrosis factor inhibitors (TNFi) are recommended
for the treatment of rheumatoid arthritis (RA) in patients with inadequate
response (IR) to prior disease-modifying antirheumatic drugs (DMARDs). This
retrospective analysis assessed the efficacy of TCZ and TNFi, alone or in
combination with DMARDs, in 1603 patients with IR to previous treatment with
either DMARDs (DMARD-IR) and/or TNFi (TNFi-IR), initiating treatment with TCZ or
a TNFi, managed in routine clinical practice. Patients were grouped according to
treatment history and treatment initiated: DMARD-IR patients initiating
treatment with TCZ + DMARD (DMARD-IR TCZ) or TNFi + DMARD (DMARD-IR TNFi),
DMARD-IR and/or TNFi-IR patients initiating treatment with TCZ monotherapy (TCZ
mono) or TNFi monotherapy (TNFi mono), and TNFi-IR patients initiating treatment
with TCZ + DMARD (TNFi-IR TCZ) or TNFi + DMARD (TNFi-IR TNFi). Patients
initiating treatment with TCZ generally had more severe disease and longer
disease duration compared with the corresponding TNFi group. Significantly more
patients achieved remission (DAS28 ESR <2.6) in the TCZ groups compared with
corresponding TNFi groups (DMARD-IR, TCZ 44.0 % vs. TNFi 29.6 %; monotherapy,
TCZ 37.2 % vs. TNFi 30.2 %; TNF-IR, TCZ 41.3 % vs. TNFi 19.2 %; p < 0.001 for
all comparisons). More patients achieved moderate-good responses (EULAR
criteria) in the TCZ treatment groups (79-85 %) compared with TNFi treatment
groups (65-81 %). Patient-reported outcomes showed greater improvements in TCZ
compared with TNFi groups. In patients with inadequate response to DMARDs and/or
TNFi treated in routine clinical practice, TCZ in combination with DMARDs or as
monotherapy resulted in significantly more patients achieving remission and more
marked improvements in patient-reported outcomes compared with TNF inhibitors. OBJECTIVE: To determine the utility of ultrasonography in guiding modification
of disease-modifying anti-rheumatic drug (DMARD) and steroid therapy for
inflammatory arthritis (IA) in routine clinical practice.
METHODS: In this retrospective study, we analyzed DMARD and steroid use in IA
patients referred to a rheumatologist-led ultrasound clinic. Power Doppler (PD)
vascularity and greyscale (GS) synovial hypertrophy joint findings were
categorized as positive/negative for each patient. The erythrocyte sedimentation
rate (ESR) was used as a measure of disease activity.
RESULTS: We assessed single visit data for 46 adult IA patients: 67.4% (n = 31)
rheumatoid arthritis (RA), 15.2% (n = 7) psoriatic arthritis, 10.9% (n = 5)
spondyloarthritis, and 6.5% (n = 3) undifferentiated IA. The mean ESR was 28.8
mm/h. Thirty-seven patients with both GS and PD ultrasound results were
subsequently analyzed. All patients (n = 10) escalated and/or initiated on DMARD
and 9/10 patients escalated or initiated on steroids were PD and GS positive.
Six of seven patients with dose reduction and/or cessation of DMARDs and five of
seven patients with dose reduction or cessation of steroids were PD negative. Of
six patients who were GS positive and PD negative, three had dose reduction
and/or cessation of DMARDs, while four had dose reduction of steroids; none of
the six patients had DMARD/steroid escalation.
CONCLUSION: By clarifying joint inflammation in an IA cohort with overall low
ESR, ultrasonography of physician-selected joints can improve clinical
assessment, resulting in treatment modification. Positive PD findings were
particularly influential, while the clinical significance of GS positivity alone
requires further investigation. BACKGROUND: Rheumatoid arthritis (RA) is the most common chronic inflammatory
disorder and is associated with progressive destruction of synovial joints and
physical disability. Therapies with known benefits include disease-modifying
antirheumatic drugs (DMARDs), such as methotrexate, as well as more recent
biologic agents, such as tumor necrosis factor inhibitors (anti-TNF therapy).
METHOD: This was a retrospective study, which included 205 RA and 112 early RA
(ERA) patients from the Rheumatology Clinic at Gaziantep University School of
Medicine Research Center as well as 104 healthy controls.
RESULTS: The mean neutrophil to lymphocyte ratio (NLR) was found to be 3.15 ±
2.64 in the patient group and 2.03 ± 0.94 in the control group. The mean
platelet to lymphocyte ratio (PLR) was 162.39 ± 107.76 in the patient group and
131.23 ± 48.09 in the control group. There was a significant difference in both
the NLR and PLR between the patient and control groups (both p < 0.01). There
was a significant difference in both the NLR and PLR between patients with
active disease and remission (both p < 0.001) in RA, including anti-TNF therapy
and DMARDs groups. There was a significant difference in NLR (p = 0.001) but not
in PLR (p = 0.051) between active disease and remission in ERA.
CONCLUSION: The results of the present study suggest that the NLR may be
considered a useful marker of disease activity in RA and one that can aid the
diagnosis of ERA. The PLR can be used in the assessment of disease activity in
RA patients undergoing anti-TNF therapy but is not suitable for diagnosing ERA. BACKGROUND: Healthcare of patients with rheumatoid arthritis (RA) in Germany has
mainly been evaluated in the past in RA cohorts from specialized arthritis
centers. This study investigated rheumatological care on a population basis,
using claims data from a nationwide statutory health insurance fund (BARMER GEK)
in combination with patient-reported outcomes from a questionnaire survey of
insured persons with RA.
METHODS: Data from insurants aged 18-79 years with M05 (seropositive RA) or M06
(other RA, ICD-10) diagnoses were analyzed concerning diagnostics, medication
and prescribing physician. A 31-item questionnaire covering patient reported
diagnosis, healthcare utilization and burden of illness was sent to a stratified
random sample of 6193 insured persons. Data from the respondents regarding
rheumatological care and disease status were evaluated.
RESULTS: In 2013 and 2014, a total of 96,921 adults with M05 or M06 diagnosis
were insured. The questionnaire was answered by 51% of the sample and of these
81% confirmed the RA diagnosis. RA had been diagnosed by a rheumatologist in 59%
of the cases, 70% reported moderate to severe pain and 46% had functional
disability. Between at least 40% (claims data) and up to 68% (respondents) were
in specialized rheumatological care. Treatment with disease-modifying
antirheumatic drugs (DMARDs) was 61% (claims data) and 63% (respondents) in
persons in rheumatological care but only 18% outside rheumatological care.
CONCLUSION: The results indicate that specialized rheumatological care is
required to provide adequate treatment for patients with RA in Germany. Patients
with higher age and patients with M06 diagnosis had less drug prescriptions and
were less frequently treated by rheumatologists. OBJECTIVES: This is a demand-based infodemiology study using the Google Trends
and AdWords tools to illustrate infodemiology's potential use in rheumatology.
The study investigates three questions in North American countries: (1) What
terms associated with "rheumatology" and "arthritis" do people search for on
Google? (2) What is the search volume for disease-modifying antirheumatic drugs
(DMARDs)? and (3) What is the search volume for the term "arthritis" compared
with for "hepatitis C" and "breast cancer"?
METHODS: We conducted independent searches by country and search term for
2015-2017. Seventeen DMARDs were searched for 2015 through May 2018, with the
turmeric remedy included for comparison. Data were exported to Excel for further
analysis, adjusted by country population, and expressed as searches per 100,000
inhabitants (SpTh).
RESULTS: There were approximately 550 associated terms for "arthritis" in each
country, and 5679 SpTh for DMARDs across the three countries. Searches for
turmeric numbered slightly lower than for all DMARDs together in Canada and the
USA, but were 70% higher in Mexico. Turmeric was also searched four times more
than the most-searched biological DMARD in Canada and the USA, and 60 times more
in Mexico. Arthritis was more commonly searched for in Canada than hepatitis C
and breast cancer, but hepatitis C was highest in the USA and breast cancer in
Mexico. Monthly trends did not show expected peaks associated with arthritis
awareness campaigns.
CONCLUSION: Infodemiology provides preliminary information that could help in
generating hypotheses, assessing health-care interventions, or even in providing
patient-centered care. |
What is the aim of the MitoCeption protocol? | The MitoCeption protocol directly and quantitatively transfer mitochondria, isolated from cell type A, to recipient cell type B. | Author information:
(1)1] IRMB CHU Saint Eloi, 80 rue Augustin Fliche, 34295 Montpellier cedex 5,
University of Montpellier, France [2] Inserm U1183,CNRS UMR 5535/IFR122, 1919
route de Mende, 34293 Montpellier Cedex 5, University of Montpellier, France.
(2)Institut de Génétique Moléculaire de Montpellier, CNRS UMR 5535/IFR122, 1919
route de Mende, 34293 Montpellier Cedex 5, University of Montpellier, France.
(3)1] Univ Grenoble Alpes, 38000 Grenoble, France [2] Inserm, U823 and U836,
38000 Grenoble, France [3] Grenoble University hospital, Institut of Biologie
and Pathology, 38000 Grenoble, France.
(4)1] Univ Grenoble Alpes, 38000 Grenoble, France [2] Inserm, U823 and U836,
38000 Grenoble, France [3] French blood company/Grenoble University hospital,
Cell Therapy Unit, 38000 Grenoble, France.
(5)1] IRMB CHU Saint Eloi, 80 rue Augustin Fliche, 34295 Montpellier cedex 5,
University of Montpellier, France [2] Inserm U1051, Montpellier, France.
(6)1] IRMB CHU Saint Eloi, 80 rue Augustin Fliche, 34295 Montpellier cedex 5,
University of Montpellier, France [2] Inserm U1183,CNRS UMR 5535/IFR122, 1919
route de Mende, 34293 Montpellier Cedex 5, University of Montpellier, France [3]
Department for Biotherapy at CHU Lapeyronie University Hospital, Montpellier,
France. |
Can prevnar 13 be used in children? | Yes, PCV13 is approved for routine vaccination of all infants as a 4-dose series at age 2, 4, 6, and 12-15 months for children who previously received 1 or more doses of the 7-valent pneumococcal conjugate vaccine (PCV7), and for children with underlying medical conditions that increase their risk for pneumococcal disease or its complications. | OBJECTIVE: To review the immunogenicity, efficacy, and safety of the 13-valent
pneumococcal conjugate vaccine (PCV13) for use in pediatric patients.
DATA SOURCES: A MEDLINE search (2000-September 2011) was conducted using the key
words Streptococcus pneumoniae and pneumococcal conjugate vaccine for clinical
trials, limited to studies conducted in humans and published in English.
STUDY SELECTION AND DATA EXTRACTION: Randomized, controlled, multicenter trials
were reviewed and included to evaluate the safety and efficacy of PCV13.
Literature on the epidemiology and pathology of pneumococcal infections and
recommendations from the Advisory Committee on Immunization Practices (ACIP)
were also reviewed.
DATA SYNTHESIS: PCV13 is approved for routine vaccination of all infants as a
4-dose series at age 2, 4, 6, and 12-15 months for children who previously
received 1 or more doses of the 7-valent pneumococcal conjugate vaccine (PCV7),
and for children with underlying medical conditions that increase their risk for
pneumococcal disease or its complications. PCV13 has comparable immunogenicity
to the serotypes common with PCV7 and also provides protection against 6
additional pneumococcal serotypes. PCV13 has also been shown to have a
comparable adverse reaction profile to PCV7.
CONCLUSIONS: Based on published immunogenicity and safety data, as well as the
recent recommendations by the ACIP for routine use in infants and indications
for high-risk pediatric patients, PCV13 is a revised formulation of pneumococcal
vaccine that should be included on pharmacy formularies. |
Was stelara developed by Amgen? | Stelara was developed by Janssen Pharmaceuticals, Inc., Horsham, PA, USA. | BACKGROUND: Several biologic therapies are approved by the National Institute
for Health and Care Excellence (NICE) for psoriatic arthritis (PsA) patients who
have had an inadequate response to two or more synthetic disease-modifying
antirheumatic drugs (DMARDs). NICE does not specifically recommend switching
from one biologic to another, and only ustekinumab (UST; STELARA®, Janssen
Pharmaceuticals, Inc., Horsham, PA, USA) is recommended after anti-tumour
necrosis factor failure. Secukinumab (SEC; COSENTYX®, Novartis International AG,
Basel, Switzerland) and certolizumab pegol (CZP; CIMZIA®, UCB Pharma, Brussels,
Belgium) have not previously been appraised by NICE.
OBJECTIVE: To determine the clinical effectiveness and cost-effectiveness of CZP
and SEC for treating active PsA in adults in whom DMARDs have been inadequately
effective.
DESIGN: Systematic review and economic model.
DATA SOURCES: Fourteen databases (including MEDLINE and EMBASE) were searched
for relevant studies from inception to April 2016 for CZP and SEC studies;
update searches were run to identify new comparator studies.
REVIEW METHODS: Clinical effectiveness data from randomised controlled trials
(RCTs) were synthesised using Bayesian network meta-analysis (NMA) methods to
investigate the relative efficacy of SEC and CZP compared with comparator
therapies. A de novo model was developed to assess the cost-effectiveness of SEC
and CZP compared with the other relevant comparators. The model was specified
for three subpopulations, in accordance with the NICE scope (patients who have
taken one prior DMARD, patients who have taken two or more prior DMARDs and
biologic-experienced patients). The models were further classified according to
the level of concomitant psoriasis.
RESULTS: Nineteen eligible RCTs were included in the systematic review of
short-term efficacy. Most studies were well conducted and were rated as being at
low risk of bias. Trials of SEC and CZP demonstrated clinically important
efficacy in all key clinical outcomes. At 3 months, patients taking 150 mg of
SEC [relative risk (RR) 6.27, 95% confidence interval (CI) 2.55 to 15.43] or CZP
(RR 3.29, 95% CI 1.94 to 5.56) were more likely to be responders than patients
taking placebo. The NMA results for the biologic-naive subpopulations indicated
that the effectiveness of SEC and CZP relative to other biologics and each other
was uncertain. Limited data were available for the biologic-experienced
subpopulation. Longer-term evidence suggested that these newer biologics reduced
disease progression, with the benefits being similar to those seen for older
biologics. The de novo model generated incremental cost-effectiveness ratios
(ICERs) for three subpopulations and three psoriasis subgroups. In subpopulation
1 (biologic-naive patients who had taken one prior DMARD), CZP was the optimal
treatment in the moderate-severe psoriasis subgroup and 150 mg of SEC was
optimal in the subgroups of patients with mild-moderate psoriasis or no
concomitant psoriasis. In subpopulation 2 (biologic-naive patients who had taken
two or more prior DMARDs), etanercept (ETN; ENBREL®, Pfizer Inc., New York City,
NY, USA) is likely to be the optimal treatment in all subgroups. The ICERs for
SEC and CZP versus best supportive care are in the region of £20,000-30,000 per
quality-adjusted life-year (QALY). In subpopulation 3 (biologic-experienced
patients or patients in whom biologics are contraindicated), UST is likely to be
the optimal treatment (ICERs are in the region of £21,000-27,000 per QALY). The
optimal treatment in subpopulation 2 was sensitive to the choice of evidence
synthesis model. In subpopulations 2 and 3, results were sensitive to the
algorithm for Health Assessment Questionnaire-Disability Index costs. The
optimal treatment is not sensitive to the use of biosimilar prices for ETN and
infliximab (REMICADE®, Merck Sharp & Dohme, Kenilworth, NJ, USA).
CONCLUSIONS: SEC and CZP may be an effective use of NHS resources, depending on
the subpopulation and subgroup of psoriasis severity. There are a number of
limitations to this assessment, driven mainly by data availability.
FUTURE WORK: Trials are needed to inform effectiveness of biologics in
biologic-experienced populations.
STUDY REGISTRATION: This study is registered as PROSPERO CRD42016033357.
FUNDING: The National Institute for Health Research Health Technology Assessment
programme. |
List off label uses for Rituximab. | Off label uses for rituximab are for poly- and dermatomyositis, multiple sclerosis, immune thrombocytopenia, systemic lupus erythematosus (SLE), lupus nephritis (LN), and other immune diseases. | Rituximab is increasingly used off label for difficult-to-treat auto-immune
diseases. We reviewed the main case series or clinical studies to identify the
best indications of rituximab and the situations at substantial risks for
adverse events. Refractory immune thrombocytopenic purpura was the main
indication. However, the long term benefit-to-risk ratio of rituximab treatment
before or after splenectomy is unknown. A single 375 mg/m2 infusion may be as
efficacious as the classical four infusions cycle. Rituximab is the best
treatment for cold agglutinin disease. In warm agglutinin auto-immune anaemia,
its efficacy has essentially been reported in chronic lymphocytic leukemia (CLL)
patients and in children. In CLL patients, lethal adverse events occurred in
patients also receiving cyclophosphamide. Rituximab seems to have an interesting
benefit-to-risk ratio in Wegener granulomatosis (excepted in granulomatous
lesions), HCV-associated symptomatic cryoglobulinemia in patients unresponsive
to anti-viral therapy, pemphigus and thrombotic thrombocytopenic purpura.
Efficacy and safety data in lupus are difficult to interpret. Serum sickness
disease is not exceptional in immune thrombocytopenic purpura (ITP), lupus and
sicca syndrome patients. A substantial infectious risk has been reported in
pemphigus patients and in post-renal transplant cryoglobulinemia. Double-blind
randomised controlled trials and phase IV studies are mandatory in most clinical
settings to confirm the overall favourable perception of rituximab benefit to
risk ratio. BACKGROUND: Rituximab, an anti-CD20 B-cell depleting monoclonal antibody, is
increasingly prescribed off-label for a range of autoimmune diseases. There has
not previously been an audit of off-label rituximab use in the Northern
Territory, where the majority of patients are Aboriginal.
AIMS: To evaluate retrospectively off-label rituximab use in autoimmune diseases
in the Top End of the Northern Territory.
METHODS: We performed a retrospective audit of 8 years of off-label rituximab
use at the Royal Darwin Hospital, the sole tertiary referral centre for the
Darwin, Katherine and East Arnhem regions. Electronic and paper records were
reviewed for demographic information, diagnosis/indication for rituximab, doses,
previous/concomitant immunosuppression, clinical outcomes and specific adverse
events.
RESULTS: Rituximab was prescribed off-label to 66 patients for 24 autoimmune
diseases. The majority of patients (62.1%) were Aboriginal and 60.6% female. The
most common indications were refractory/relapsing disease despite standard
therapies (68.7%) or severe disease with rituximab incorporated into an
induction immunosuppressive regimen (19.4%). Systemic lupus erythematosus was
the underlying diagnosis in 28.8% of cases. A clinically significant response
was demonstrated in 74.2% of cases overall. There were 18 clinically significant
infections; however, 13 were in patients receiving concurrent immunosuppressive
therapy. There was a total of nine deaths from any cause.
CONCLUSION: Rituximab has been used off-label for a range of autoimmune diseases
in this population with a high proportion of Aboriginal patients successfully
and safely in the majority of cases. In patients with immune thrombocytopenia who do not adequately respond to
first-line therapy, there is no clear consensus on which second-line therapy to
initiate and when. This situation leads to suboptimal approaches, including
prolonged exposure to treatments that are not intended for long-term use (eg,
corticosteroids) and overuse of off-label therapies (eg, rituximab) while
approved, more efficacious options exist. These approaches may not only fail to
address symptoms and burden of disease, but may also worsen health-related
quality of life. A better understanding of available second-line treatments may
ensure best use of therapeutic options and thereby optimize patient outcomes. OBJECTIVES: Off-label use of rituximab to treat MS patients in Sweden is high,
and the need for long-term safety data may not be met. Our objectives were to
assess the rate of rituximab prescription in patients with multiple sclerosis in
Sweden and, in addition, to evaluate the safety of rituximab in a single centre
for patients with multiple sclerosis.
MATERIAL AND METHODS: Review of the Swedish MS register was performed to study
the number of MS patients treated with rituximab during the last 6 years.
Investigation also included a retrospective review of medical files in search
for possible side effects/adverse events in all adult patients with MS treated
with rituximab at Uppsala University Hospital.
RESULTS: Presently, in Sweden the rate of rituximab prescriptions in relation to
other annually started of disease- modifying drugs in MS is 53.5%.
CONCLUSIONS: The share of MS patients in Sweden who are treated with rituximab
is very high, and also rapidly increasing. Taken into account the off-label use,
cases with adverse medical conditions that could possibly be related to
rituximab use should be reported thoroughly. OBJECTIVE: Conventional treatment of systemic lupus erythematosus (SLE) and
lupus nephritis (LN) is associated with damage accrual, hence increased
morbidity rate. Off-label use of rituximab (RTX) has shown significant promise
in this patient group; however, data are still controversial. We aimed to
analyze the outcomes of RTX therapy in refractory lupus using a meta-analysis
approach.
METHODS: Electronic search of the medical literature was conducted using a
combination of relevant keywords to retrieve studies on the safety and efficacy
of RTX in SLE and LN patients. Results were screened against our inclusion and
exclusion criteria and two reviewers independently extracted the data for
analysis. Comprehensive meta-analysis software was used to pool the data from
individual studies and provide summary effect estimates.
RESULTS: Thirty-one studies that enrolled 1112 patients were finally eligible
for the meta-analysis. The overall global, complete, and partial response rates
to RTX therapy were 72%, 46%, and 32%, respectively. RTX significantly decreased
Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and British Isles
Lupus Activity Group (BILAG) scores (p<0.001). Prednisone dose was significantly
reduced after RTX treatment in both SLE and LN groups (p<0.001), and proteinuria
was lowered in SLE (p<0.001) than in LN patients (p=0.07). Infection and
infusion-related reactions were the most common side effects.
CONCLUSION: RTX therapy in refractory SLE and LN patients proved clinical
efficacy and favorable safety outcomes. Larger well-designed randomized clinical
trials are warranted. |
Can mitochondria pass through membrane nanotubes? | Yes,
Membrane nanotubes (MNTs) act as "highways" between cells to facilitate the transfer of multiple signals and play an important role in many diseases. Our previous work reported on the transfer of mitochondria via MNTs between cardiomyocytes (CMs) and cardiac myofibroblasts (MFs). | Membrane otubes (MNTs) act as "highways" between cells to facilitate the
transfer of multiple signals and play an important role in many diseases. Our
previous work reported on the transfer of mitochondria via MNTs between
cardiomyocytes (CMs) and cardiac myofibroblasts (MFs); however, the elucidation
of the underlying mechanism and pathophysiological significance of this transfer
requires additional study. In this study, we determined that the mean movement
velocity of mitochondria in MNTs between CMs and MFs was approximately
17.5 ± 2.1 nm/s. Meanwhile, treatment with microtubule polymerisation inhibitors
nocodazole or colcemid in cell culture decreased mitochondrial velocity, and
knockdown of the microtubule motor protein kinesin family member 5B (KIF5B) led
to a similar effect, indicating that mitochondrial movement was dependent on
microtubules and the motor protein KIF5B. Furthermore, we showed that
hypoxia/reoxygenation-induced CM apoptosis was attenuated by coculture with
intact or hypoxia/reoxygenation-treated MFs, which transferred mitochondria to
CMs. This rescue was prevented either by separating the cells using Transwell
culture or by impairing mitochondrial transfer with nocodazole or colcemid
treatment. In conclusion, as a novel means of intercellular communication, MNTs
rescue distressed CMs from apoptosis by transporting mitochondria along
microtubules via KIF5B. |
What is Quorum Sensing in bacteria? | In many pathogenic microorganisms, communication systems, collectively termed quorum sensing (QS), | Quorum sensing is a signaling mechanism through which bacteria modulate a number
of cellular functions (genes), including sporulation, biofilm formation,
bacteriocin production, virulence responses, as well as others. Quorum sensing
is a mechanism of cell-to-cell communication and is mediated by extracellular
chemical signals generated by the bacteria when specific cell densities are
reached. When the concentration of the signal (and cell population) is
sufficiently high, the target gene or genes are either activated or repressed.
Quorum sensing increases the ability of the bacteria to have access to nutrients
or to more favorable environmental niches and enhances bacterial defenses
against eukaryotic hosts, competing bacteria, and environmental stresses. The
physiological and clinical aspects of quorum sensing have received considerable
attention and have been studied at the molecular level. Little is known,
however, on the role of quorum sensing in food spoilage or in the growth and/or
toxin production of pathogens present in food. A number of compounds have been
isolated or synthesized that antagonize quorum sensors, and application of these
antagonists may potentially be useful in inhibiting the growth or virulence
mechanisms of bacteria in different environments, including food. It is
important that food microbiologists have an awareness and an understanding of
the mechanisms involved in bacterial quorum sensing, since strategies targeting
quorum sensing may offer a means to control the growth of undesirable bacteria
in foods. Quorum sensing is used by a large variety of bacteria to regulate gene
expression in a cell-density-dependent manner. Bacteria can synchronize
population behavior using small molecules called autoinducers that are produced
by cognate synthases and recognized by specific receptors. Quorum sensing plays
critical roles in regulating diverse cellular functions in bacteria, including
bioluminescence, virulence gene expression, biofilm formation, and antibiotic
resistance. The best-studied autoinducers are acyl homoserine lactone (AHL)
molecules, which are the primary quorum sensing signals used by Gram-negative
bacteria. In this review we focus on the AHL-dependent quorum sensing system and
highlight recent progress on structural and mechanistic studies of AHL synthases
and the corresponding receptors. Crystal structures of LuxI-type AHL synthases
provide insights into acyl-substrate specificity, but the current knowledge is
still greatly limited. Structural studies of AHL receptors have facilitated a
more thorough understanding of signal perception and established the molecular
framework for the development of quorum sensing inhibitors. Quorum sensing is a process of cell-cell communication that allows bacteria to
share information about cell density and adjust gene expression accordingly.
This process enables bacteria to express energetically expensive processes as a
collective only when the impact of those processes on the environment or on a
host will be maximized. Among the many traits controlled by quorum sensing is
the expression of virulence factors by pathogenic bacteria. Here we review the
quorum-sensing circuits of Staphylococcus aureus, Bacillus cereus, Pseudomonas
aeruginosa, and Vibrio cholerae. We outline these canonical quorum-sensing
mechanisms and how each uniquely controls virulence factor production.
Additionally, we examine recent efforts to inhibit quorum sensing in these
pathogens with the goal of designing novel antimicrobial therapeutics. The term 'quorum sensing' describes intercellular bacterial communication which
regulates bacterial gene expression according to population cell density.
Bacteria produce and secrete small molecules, named autoinducers, into the
intercellular space. The concentration of these molecules increases as a
function of population cell density. Once the concentration of the stimulatory
threshold is reached, alteration in gene expression occurs. Gram-positive and
Gram-negative bacteria possess different types of quorum sensing systems.
Canonical LuxI/R-type/acyl homoserine lactone mediated quorum sensing system is
the best studied quorum sensing circuit and is described in Gram-negative
bacteria which employ it for inter-species communication mostly. Gram-positive
bacteria possess a peptide-mediated quorum sensing system. Bacteria can
communicate within their own species (intra-species) but also between species
(inter-species), for which they employ an autoinducer-2 quorum sensing system
which is called the universal language of the bacteria. Periodontal pathogenic
bacteria possess AI-2 quorum sensing systems. It is known that they use it for
regulation of biofilm formation, iron uptake, stress response and virulence
factor expression. A better understanding of bacterial communication mechanisms
will allow the targeting of quorum sensing with quorum sensing inhibitors to
prevent and control disease. In most bacteria, a global level of regulation, termed quorum sensing (QS),
exists involving intercellular communication via the production and response to
cell density-dependent signal molecules. QS has been associated with a number of
important features in bacteria including virulence regulation and biofilm
formation. Consequently, there is considerable interest in understanding,
detecting, and inhibiting QS. N-acylated homoserine lactones (AHLs) are used as
extracellular QS signals by a variety of Gram-negative bacteria. Chromobacterium
violaceum, commonly found in soil and water, produces the characteristic purple
pigment violacein, regulated by AHL-mediated QS. Based on this readily observed
pigmentation phenotype, C. violaceum strains can be used to detect various
aspects of AHL-mediated QS activity. In another commonly used bioassay organism,
Agrobacterium tumefaciens, QS can be detected by the use of a reporter gene such
as lacZ. Here, we describe several commonly used approaches incorporating C.
violaceum and A. tumefaciens that can be used to detect AHL and QS inhibitors.
Due to the inherent low susceptibility of biofilm bacteria to antimicrobial
agents, biofilm dispersion, whereby bacteria reenter the planktonic community,
is another increasingly important area of research. At least one signal,
distinct from traditional QS, has been identified and there are a variety of
other environmental factors that also trigger dispersion. We describe a
microtiter-based experimental strategy whereby potential biofilm dispersion
compounds can be screened. Many Proteobacteria synthesize acyl-homoserine lactone (AHL) molecules for use
as signals in cell density-dependent gene regulation known as quorum sensing
(QS) and response. AHL detection protocols are essential to QS researchers and
several techniques are available, including a 14C-AHL radiolabel assay. This
assay is based on the uptake of radiolabeled methionine by living cells and
conversion of the radiolabel into S-adenosylmethionine (SAM). The radiolabeled
SAM is then incorporated into AHL signal by an AHL synthase enzyme. Here we
describe a methodology to perform the AHL radiolabel assay, which is unbiased,
relatively fast, and very sensitive compared to other AHL detection protocols. |
What is the cause of Krabbe disease? | Globoid cell leukodystrophy (GLD), or Krabbe disease, is an inherited, neurologic disorder that results from deficiency of a lysosomal enzyme, galactosylceramidase. | Krabbe disease (KD) is a rare disease caused by the deficiency of
β-galactocerebrosidase. This study investigated 22 unrelated Chinese patients,
including their clinical presentations, plasma psychosine levels and
β-galactocerebrosidase gene mutations. We found the late-onset form of KD
present in 82% of the patients in our study, which was more prevalent than in
patients from other populations. Plasma psychosine levels were elevated in KD,
which were correlated with the severity of clinical presentations. Sanger
sequencing identified 8 novel mutations, including 7 missense mutations,
p.H253Y, p.S259L, p.P318L, p.F350V, p.T428A, p.L530P, p.G586D, and 1 splicing
mutation, c.1251+1G>A. Quantitative real-time polymerase chain reaction (PCR)
and multiplex ligation-dependent probe amplification identified a novel exon 12
and 14 deletion, separately. Next generation sequencing, applied at the final
step, revealed 2 missense mutant alleles missed using Sanger sequencing. The
most common mutation in Chinese population is p.P154H, which accounts for 20.5%
of alleles. Consistent with the higher prevalence of the late-onset form of KD,
missense mutations predominated in our study, different with the common mutation
types in Europe and Japan. This work was the first large-scale study of Chinese
KD patients describing their clinical, biochemical and genetic characteristics,
which furthered our understanding of this classical neurological lysosomal
storage disease. Globoid cell leukodystrophy (GLD), or Krabbe disease, is an inherited,
neurologic disorder that results from deficiency of a lysosomal enzyme,
galactosylceramidase. Most commonly, deficits of galactosylceramidase result in
widespread central and peripheral nervous system demyelination and death in
affected infants typically by 2 years of age. Hematopoietic stem-cell
transplantation is the current standard of care in children diagnosed prior to
symptom onset. However, disease correction is incomplete. Herein, the first
adeno-associated virus (AAV) gene therapy experiments are presented in a
naturally occurring canine model of GLD that closely recapitulates the clinical
disease progression, neuropathological alterations, and biochemical
abnormalities observed in human patients. Adapted from studies in twitcher mice,
GLD dogs were treated by combination intravenous and intracerebroventricular
injections of AAVrh10 to target both the peripheral and central nervous systems.
Combination of intravenous and intracerebroventricular AAV gene therapy had a
clear dose response and resulted in delayed onset of clinical signs, extended
life-span, correction of biochemical defects, and attenuation of neuropathology.
For the first time, therapeutic effect has been established in the canine model
of GLD by targeting both peripheral and central nervous system impairments with
potential clinical implications for GLD patients. BACKGROUND: Krabbe disease is a rare neurodegenerative genetic disorder caused
by deficiency of galactocerebrosidase. Patients with the infantile form of
Krabbe disease can be treated at a presymptomatic stage with human stem cell
transplantation which improves survival and clinical outcomes. However, without
a family history, most cases of infantile Krabbe disease present after onset of
symptoms and are ineligible for transplantation. In 2006, New York began
screening newborns for Krabbe disease to identify presymptomatic cases. To
ensure that those identified with infantile disease received timely treatment,
New York public health and medical systems took steps to accurately diagnose and
rapidly refer infants for human stem cell transplantation within the first few
weeks of life. After 11 years of active screening in New York and the
introduction of Krabbe disease newborn screening in other states, new
information has been gained which can inform the design of newborn screening
programs to improve infantile Krabbe disease outcomes.
FINDINGS: Recent information relevant to Krabbe disease screening, diagnosis,
and treatment were assessed by a diverse group of public health, medical, and
advocacy professionals. Outcomes after newborn screening may improve if
treatment for infantile disease is initiated before 30 days of life. Newer
laboratory screening and diagnostic tools can improve the speed and specificity
of diagnosis and help facilitate this early referral. Given the rarity of Krabbe
disease, most recommendations were based on case series or expert opinion.
CONCLUSION: This report updates recommendations for Krabbe disease newborn
screening to improve the timeliness of diagnosis and treatment of infantile
Krabbe disease. In the United States, several states have begun or are
considering Krabbe disease newborn screening. These recommendations can guide
public health laboratories on methodologies for screening and inform clinicians
about the need to promptly diagnose and treat infantile Krabbe disease. The
timing of the initial referral after newborn screening, the speed of diagnostic
confirmation of infantile disease, and the transplantation center's experience
and ability to rapidly respond to a suspected patient with newly diagnosed
infantile Krabbe disease are critical for optimal outcomes. |
Name a CFL2 mutation which is associated with nemaline myopathy? | A mutation in CFL2 was identified in a family with nemaline myopathy, namely a homozygous missense mutation in exon 2 (c.19G>A, p.Val7Met). | Nemaline myopathy and myofibrillar myopathy are heterogeneous myopathies that
both comprise early-onset forms. We present two sisters from a consanguineous
Iraqi Kurdish family with predomit axial and limb girdle weakness. Muscle
biopsies showed features of both nemaline myopathy and myofibrillar myopathy. We
performed homozygosity mapping in both siblings using an Affymetrix 250K Nspl
SNP array. One of the overlapping homozygous regions harbored the gene CFL2.
Because a mutation in CFL2 was identified in a family with nemaline myopathy, we
performed sequence analysis of the gene and a novel homozygous missense mutation
in exon 2 (c.19G>A, p.Val7Met) of CFL2 was identified in both siblings. CFL2
encodes the protein cofilin-2, which plays an important role in regulation of
sarcomeric actin filaments. To our knowledge, this is the second family in which
a mutation in CFL2 causes an autosomal recessive form of congenital myopathy
with features of both nemaline and myofibrillar myopathy. Given the clinical
variability and the multitude of histological features of congenital myopathies,
CFL2 sequence analysis should be considered in patients presenting with an
autosomal recessive form of congenital myopathy. |
What cellular process is the gene product of NANOG involved in? | NANOG is a transcription factor and a biomarker of cancer and pluripotent stem cells. | OBJECTIVE: The objective of this study was to explore the prognostic value of
cancer stem cell markers, namely CD133, NANOG, and NOTCH1, in early stage oral
squamous cell carcinoma (OSCC).
MATERIALS AND METHODS: One hundred forty-four patients with early stage
(cT1T2N0) OSCC were identified from a pre-existing database of patients with
oral cancer. We examined the impact of the immunohistochemical expression of
CD133, NANOG, and NOTCH1 in OSCC. Overall survival (OS) curves were calculated
using the Kaplan-Meier method. Predictors of outcome were identified using
multivariate analysis.
RESULTS: We found that CD133, NANOG, and NOTCH1 were significantly associated
with lymph node metastasis, and NOTCH1 was also significantly associated with
depth of invasion and locoregional recurrence.
CONCLUSIONS: NOTCH1 was identified as an independent prognostic factor for OS.
CLINICAL RELEVANCE: NOTCH1 might prove to be a useful indicator for high-risk
patients with occult metastases from early stage OSCC. The successful development from a single-cell zygote into a complex
multicellular organism requires precise coordination of multiple cell-fate
decisions. The very first of these is lineage specification into the inner cell
mass (ICM) and trophectoderm (TE) during mammalian preimplantation development.
In mouse embryos, transcription factors (TFs) such as Oct4, Sox2, and Nanog are
enriched in cells of ICM, which gives rise to the fetus and yolk sac.
Conversely, TFs such as Cdx2 and Eomes become highly upregulated in TE, which
contribute to the placenta. Here, we review the current understanding of key
transcriptional control mechanisms and genes responsible for these distinct
differences during the first cell lineage specification. In particular, we
highlight recent insights gained through advances in genome manipulation, live
imaging, single-cell transcriptomics, and loss-of-function studies. Cancer stem cells (CSCs) play a central role in the development of breast
cancer. The canonical Wnt/β-catenin signal pathway is critical for maintaining
CSCs characteristics. Diallyl trisulfide (DATS), a natural organosulfur compound
from the garlic, exhibits effective antitumor properties. However, the role of
DATS in regulating breast CSCs activity and the underlying molecular mechanisms
remain obscure. In the present study, we reported that DATS efficiently
inhibited the viability of breast CSCs as evidenced by reducing turmorspheres
formation, decreasing the expression of breast CSCs markers (CD44, ALDH1A1,
Nanog, and Oct4), as well as inhibiting proliferation and inducing apoptosis.
Furthermore, we showed that DATS downregulated the activity of Wnt/β-catenin
pathway, while LiCl-triggered Wnt/β-catenin activation diminished DATS
inhibition on breast CSCs. Taken together, our results illustrated that DATS
suppressed breast CSCs through inhibiting Wnt/β-catenin pathway activation.
These novel findings could provide new insights into the molecular mechanisms of
breast CSCs regulation as well as its target intervention and might provide new
strategies for preventing and treating breast cancers. Author information:
(1)Family Planning Research Institute, Tongji Medical College, Huazhong
University of Science and Technology, Wuhan 430030, China.
(2)Family Planning Research Institute, Tongji Medical College, Huazhong
University of Science and Technology, Wuhan 430030, China; Wuhan Tongji
Reproductive Medicine Hospital, Wuhan 430013, China.
(3)Wuhan Tongji Reproductive Medicine Hospital, Wuhan 430013, China.
(4)Zhong Shen Bioscience Inc., Wuhan, China.
(5)Department of Cell Biology and Neuroscience, Montana State University,
Bozeman, MT 59717, USA; Department of Chemistry and Biochemistry, Montana State
University, Bozeman, MT 59717, USA.
(6)Family Planning Research Institute, Tongji Medical College, Huazhong
University of Science and Technology, Wuhan 430030, China; Wuhan Tongji
Reproductive Medicine Hospital, Wuhan 430013, China. Electronic address:
[email protected]. |
Name the uses of Sideritis scardica in traditional medicine. | Sideritis scardica is used in traditional medicine as a loosening agent in bronchitis and bronchial asthma; against the common cold and lung emphysema; in the treatment of inflammation, gastrointestinal disorders and coughs; and as an active constituent of dietary supplements for the prevention of anemia. Sideritis scardica has been attributed a broad range of properties such as antimicrobial, anti-inflammatory, cytotoxic, antioxidant, gastroprotective, antiglioma, and triple monoamine reuptake inhibition. | |
What are the phenotypic features of the autosomal dominant, development disease, Noonans syndrome | Noonan syndrome (NS) is an autosomal dominant disorder with vast heterogeneity in clinical and genetic features. Various symptoms have been reported for this abnormality such as short stature, unusual facial characteristics, congenital heart abnormalities, developmental complications, and an elevated tumor incidence rate | Noo syndrome is an autosomal domit disease characterized by dysmorphic
features, webbed neck, cardiac anomalies, short stature and cryptorchidism. It
shows phenotypic overlap with Costello syndrome and cardio-facio-cutaneous (CFC)
syndrome. Noo syndrome and related disorders are caused by germline mutations
in genes encoding molecules in the RAS/MAPK pathway. Recently, a
gain-of-function mutation in SHOC2, p.S2G, has been identified as causative for
a type of Noo-like syndrome characterized by the presence of loose anagen
hair. In order to understand the contribution of SHOC2 mutations to the clinical
manifestations of Noo syndrome and related disorders, we analyzed SHOC2 in 92
patients with Noo syndrome and related disorders who did not exhibit PTPN11,
KRAS, HRAS, BRAF, MAP2K1/2, SOS1 or RAF1 mutations. We found the previously
identified p.S2G mutation in eight of our patients. We developed a rapid
detection system to identify the p.S2G mutation using melting curve analysis,
which will be a useful tool to screen for the apparently common mutation. All
the patients with the p.S2G mutation showed short stature, sparse hair and
atopic skin. Six of the mutation-positive patients showed severe mental
retardation and easily pluckable hair, and one showed leukocytosis. No SHOC2
mutations were identified in leukemia cells from 82 leukemia patients. These
results suggest that clinical manifestations in SHOC2 mutation-positive patients
partially overlap with those in patients with typical Noo or CFC syndrome and
show that easily pluckable/loose anagen hair is distinctive in SHOC2
mutation-positive patients. Author information:
(1)Servicio de Reumatología. Hospital Universitario Clementino Fraga Filho,
Universidad Federal de Río de Janeiro (HUCFF-UFRJ), Río de Janeiro, Brasil.
Electronic address: [email protected].
(2)Servicio de Reumatología. Hospital Universitario Clementino Fraga Filho,
Universidad Federal de Río de Janeiro (HUCFF-UFRJ), Río de Janeiro, Brasil. |
Are protamines ubiquitously expressed? | No,
Protamines are nuclear proteins which are specifically expressed in haploid male germ cells. | Protamines are nuclear proteins which are specifically expressed in haploid male
germ cells. Their replacement of histones and binding to DNA is followed by
chromatin hypercondensation that protects DNA from negative influences by
environmental factors. Mammalian sperm contain two types of protamines: PRM1 and
PRM2. While the proportion of the two protamines is highly variable between
different species, abnormal ratios within a species are known to be associated
with male subfertility. Therefore, it is more than likely that correct protamine
expression represents a kind of chromatin checkpoint during sperm development
rendering protamines as suitable biomarkers for the estimation of sperm quality.
This review presents an overview of our current knowledge on protamines
comparing gene and protein structures between different mammalian species with
particular consideration given to man, mouse and stallion. At last, recent
insights into the possible role of inherited sperm histones for early embryo
development are provided. |
Are Crocus sativus compounds being considered against Alzheimer's disease? | Yes, it has been observed that Crocus sativus extracts and compounds have a positive effect against Alzheimer's disease. | Crocus sativus, commonly known as saffron or Kesar, is used in Ayurveda and
other folk medicines for various purposes as an aphrodisiac, antispasmodic, and
expectorant. Previous evidence suggested that Crocus sativus is linked to
improving cognitive function in Alzheimer's disease (AD) patients. The aim of
this study was to in vitro and in vivo investigate the mechanism(s) by which
Crocus sativus exerts its positive effect against AD. The effect of Crocus
sativus extract on Aβ load and related toxicity was evaluated. In vitro results
showed that Crocus sativus extract increases the tightness of a cell-based
blood-brain barrier (BBB) model and enhances transport of Aβ. Further in vivo
studies confirmed the effect of Crocus sativus extract (50 mg/kg/day, added to
mice diet) on the BBB tightness and function that was associated with reduced Aβ
load and related pathological changes in 5XFAD mice used as an AD model. Reduced
Aβ load could be explained, at least in part, by Crocus sativus extract effect
to enhance Aβ clearance pathways including BBB clearance, enzymatic degradation
and ApoE clearance pathway. Furthermore, Crocus sativus extract upregulated
synaptic proteins and reduced neuroinflammation associated with Aβ pathology in
the brains of 5XFAD mice. Crocin, a major active constituent of Crocus sativus
and known for its antioxidant and anti-inflammatory effect, was also tested
separately in vivo in 5XFAD mice. Crocin (10 mg/kg/day) was able to reduce Aβ
load but to a lesser extent when compared to Crocus sativus extract.
Collectively, findings from this study support the positive effect of Crocus
sativus against AD by reducing Aβ pathological manifestations. |
Rickettsia felis was described as a human pathogen almost two decades ago, what is it's main arthropod vector? | Cat fleas (Ctenocephalides felis) carry Rickettsia felis | Rickettsia felis was first recognised two decades ago and has now been described
as endemic to all continents except Antarctica. The rickettsiosis caused by R.
felis is known as flea-borne spotted fever or cat-flea typhus. The large number
of arthropod species found to harbour R. felis and that may act as potential
vectors support the view that it is a pan-global microbe. The main arthropod
reservoir and vector is the cat flea, Ctenocephalides felis, yet more than 20
other species of fleas, ticks, and mites species have been reported to harbour
R. felis. Few bacterial pathogens of humans have been found associated with such
a diverse range of invertebrates. With the projected increase in global
temperature over the next century, there is concern that changes to the ecology
and distribution of R. felis vectors may adversely impact public health. Rickettsia typhi, transmitted by rat fleas, causes most human flea-borne
rickettsioses worldwide. Another rickettsia, Rickettsia felis, found in cat
fleas, Ctenocephalides felis, has also been implicated as a potential human
pathogen. In the continental United States, human cases of flea-borne
rickettsioses are reported primarily from the southern regions of Texas and
California where the cat flea is considered the principal vector. In California,
more than 90% of locally acquired human cases are reported from suburban
communities within Los Angeles and Orange counties despite the almost ubiquitous
presence of cat fleas and their hosts throughout the state. The objective of
this study is to assess the presence and infection rate of Rickettsia species in
cat fleas from selected endemic and nonendemic regions of California. Cat fleas
were collected from cats in Los Angeles County (endemic region) and Sacramento
and Contra Costa counties (nonendemic region). Sequencing of 17 amplicons
confirmed the presence of R. felis in both the endemic and non-endemic regions
with a calculated maximum likelihood estimation of 131 and 234 per 1000 fleas,
respectively. R. typhi was not detected in any flea pools. Two R. felis-like
genotypes were also detected in fleas from Los Angeles County; Genotype 1 was
detected in 1 flea pool and Genotype 2 was found in 10 flea pools. Genotype 1
was also detected in a single flea pool from Sacramento County. Results from
this study show that R. felis is widespread in cat flea populations in both
flea-borne rickettsioses endemic and nonendemic regions of California,
suggesting that a high prevalence of this bacterium in cat fleas does not
predispose to increased risk of human infection. Further studies are needed to
elucidate the role of R. felis and the two R. felis-like organisms as etiologic
agents of human flea-borne rickettsioses in California. |
Are there any anti-amyloid antibody approved as drug for Alzheimer's disease treatment? | No new drugs have been approved during the past 15 years; and the available medications are not cost-effective. | Deficiency of protein phosphatase-2A is a key event in Alzheimer's disease. An
endogenous inhibitor of protein phosphatase-2A, inhibitor-1, I1PP2A, which
inhibits the phosphatase activity by interacting with its catalytic subunit
protein phosphatase-2Ac, is known to be upregulated in Alzheimer's disease
brain. In the present study, we overexpressed I1PP2A by intracerebroventricular
injection with adeno-associated virus vector-1-I1PP2A in Wistar rats. The I1PP2A
rats showed a decrease in brain protein phosphatase-2A activity, abnormal
hyperphosphorylation of tau, neurodegeneration, an increase in the level of
activated glycogen synthase kinase-3beta, enhanced expression of intraneuronal
amyloid-beta and spatial reference memory deficit; littermates treated
identically but with vector only, i.e., adeno-associated virus vector-1-enhanced
GFP, served as a control. Treatment with memantine, a noncompetitive NMDA
receptor antagonist which is an approved drug for treatment of Alzheimer's
disease, rescued protein phosphatase-2A activity by decreasing its demethylation
at Leu309 selectively and attenuated Alzheimer's disease-like pathology and
cognitive impairment in adeno-associated virus vector-1-I1PP2A rats. These
findings provide new clues into the possible mechanism of the beneficial
therapeutic effect of memantine in Alzheimer's disease patients. |
Do Crocus sativus extracts loosen the blood-brain barrier? | No, in vitro and in vivo experiments show that the Crocus sativus extract increases the tightness of a cell-based blood-brain barrier (BBB). | Crocus sativus, commonly known as saffron or Kesar, is used in Ayurveda and
other folk medicines for various purposes as an aphrodisiac, antispasmodic, and
expectorant. Previous evidence suggested that Crocus sativus is linked to
improving cognitive function in Alzheimer's disease (AD) patients. The aim of
this study was to in vitro and in vivo investigate the mechanism(s) by which
Crocus sativus exerts its positive effect against AD. The effect of Crocus
sativus extract on Aβ load and related toxicity was evaluated. In vitro results
showed that Crocus sativus extract increases the tightness of a cell-based
blood-brain barrier (BBB) model and enhances transport of Aβ. Further in vivo
studies confirmed the effect of Crocus sativus extract (50 mg/kg/day, added to
mice diet) on the BBB tightness and function that was associated with reduced Aβ
load and related pathological changes in 5XFAD mice used as an AD model. Reduced
Aβ load could be explained, at least in part, by Crocus sativus extract effect
to enhance Aβ clearance pathways including BBB clearance, enzymatic degradation
and ApoE clearance pathway. Furthermore, Crocus sativus extract upregulated
synaptic proteins and reduced neuroinflammation associated with Aβ pathology in
the brains of 5XFAD mice. Crocin, a major active constituent of Crocus sativus
and known for its antioxidant and anti-inflammatory effect, was also tested
separately in vivo in 5XFAD mice. Crocin (10 mg/kg/day) was able to reduce Aβ
load but to a lesser extent when compared to Crocus sativus extract.
Collectively, findings from this study support the positive effect of Crocus
sativus against AD by reducing Aβ pathological manifestations. |
Are artificial blood cells available? | No,
The critical point for the break through for artificial blood products did not come yet but could be ahead- | Formerly developed resuscitation fluids solely imitated the main function of the
blood -oxygen transport. A research driven by the army requested an oxygen
carrier that does not need cross typing and cooled storage. Artificial oxygen
carriers (AOC) use either the molecular oxygen bondage to hemoglobin: HBOC-
"hemoglobin based oxygen carriers" or the physical dissolution of oxygen in the
blood plasma compartment by hyperbaric pressure in perfluorocarbon emulsions
(PFC). Decades of preclinical and clinical research did pass but the results
were disappointing- in Russia, a not well designed PFC is available locally and
the only approved HBOC in South Africa is not being used much. Other products,
just prior to filing for FDA approval, did not achieve convincing study results
and research and production was stopped. Some trials have been stopped by the
FDA for safety reasons, half of trials with the primary endpoint reduction of
allogeneic transfusion requirement were unsuccessful or offset by an increased
blood requirement later. However, some ventures currently are trying to use the
knowledge gained so far and are investigating third and fourth generation
products of artificial blood components. These imitate the cellular structure of
red cells as micells, ocapsules, (ABC- artificial blood cells) or gas bubbles
(microbubbles), admixture of volume substitutes such as starches, gelatin or
albumin or use hyperbaric oxygenation [38]. Artificial platelets are in clinical
phase IIa, recombit albumin in phase III. In this article, a short overview
about the current situation on artificial blood products is given. The critical
point for the break through for artificial blood products did not come yet but
could be ahead- |
Have apolipoprotein mimetics been used in clinical trials? | Yes, apolipoprotein mimetics have entered clinical trials. | |
What are 2 organisms that can cause Human toxocariasis? | Human toxocariasis , a worldwide parasitic disease , is caused by the larval stage of intestinal nematodes of dogs and cats , namely Toxocara canis and Toxocara cati | Toxocariasis is a preventable parasitic disease that is caused by the dog and
cat roundworms Toxocara cani and T. cati, respectively. Humans become infected
when they accidently ingest infectious Toxocara eggs commonly found in
contaminated soil; children are most often affected. Clinical manifestations of
Toxocara infection in humans include ocular toxocariasis and visceral
toxocariasis. Although infection with Toxocara can cause devastating disease,
the burden of toxocariasis in the United States population remains unknown. In
addition, risk factors for acquiring infection need to be better defined, and
research needs to be conducted to better understand the pathophysiology and
clinical course of toxocariasis. Development of diagnostic tests would enable
clinicians to detect active infection, and determination of optimal drug
regiments would ensure patients were appropriately treated. Addressing these
public health gaps is necessary to understand and address the impact of
toxocariasis in the United States. Human toxocariasis which is caused mainly by the larvae of Toxocara canis and
Toxocara cati, is a worldwide zoonotic disease that can be a potentially serious
human infection. The enzyme-linked immunosorbent assay (ELISA) using T. canis
excretory-secretory (TES) antigens harvested from T. canis larvae is currently
the serological test for confirming toxocariasis. An alternative to producing
large amounts of Toxocara TES and improved diagnosis for toxocariasis is through
the development of highly specific recombit antigens such as the T. canis
second stage larva excretory-secretory 30 kDa protein (recTES-30). The aim of
this study was to evaluate the sensitivity and specificity of a rapid diagnostic
kit (RDT, named as iToxocara kit) in comparison to recTES-30 ELISA in Serendah
Orang Asli village in Selangor, Malaysia. A total of 133 subjects were included
in the study. The overall prevalence rates by ELISA and RDT were 29.3% and
33.1%, respectively, with more positive cases detected in males than females.
However, no association was found between toxocariasis and gender or age. The
percentage sensitivity, specificity, positive predictive value and negative
predictive value of RDT were 85.7%, 90.1%, 80% and 93.2%, respectively. The
prevalence for toxocariasis in this population using both ELISA and RDT was
27.1% (36/133) and the K-concordance test suggested good agreement of the two
tests with a Cohen's kappa of 0.722, P<0.01. In addition, the followed-up
Spearman rank correlation showed a moderately high correlation at R=0.704 and
P<0.01. In conclusion, the RDT kit was faster and easier to use than an ELISA
and is useful for the laboratory diagnosis of hospitalized cases of
toxocariasis. BACKGROUND: Toxocariasis is a prevalent zoonosis disease caused by the closely
related nematode species Toxocara canis and Toxocara cati which parasitise
Canidae and Felidae respectively. In paratenic hosts, larvae of these worms
cause multiple organ damage. However, how these paratenic hosts response to
these worms and whether any common biomarker can be applied for diagnosis are
still unclear.
METHODS: Excreted/secreted (E/S) antigens were prepared by culture of T. canis
larvae in vitro. Using a western blot (WB) assay the humoral IgG responses,
induced by Toxocara spp. larvae to the worm's E/S antigens in different infected
hosts including mice, rabbits and human, were examined.
RESULTS: In a mouse model of toxocariasis, intraperitoneal injection of T. canis
larvae induces inflammatory leukocyte accumulation in the liver and the lungs
but not in the brain, although a remarkable number of larvae were detected in
this organ. Mice and rabbits responded differently to Toxocara spp. resulting in
distinct heterogenous WB band patterns. Mice and rabbits both responded to a
33.1 kDa E/S constituent that turned out to be the most sensitive protein for
serodiagnosis. Sera from human toxocariasis patients showed heterogenous WB band
patterns similar to those observed in rabbits and all responded to the 33.1 kDa
band.
CONCLUSION: 33.1 kDa E/S protein can be considered as a critical common
biomarker for toxocariasis immuno-diagnosis in both paratenic animals and human
and its specificity requires further investigation. La toxocarose humaine est une zoonose parasitaire cosmopolite causée par
Toxocara canis et Toxocara catisqui sont des ascarides des chiens et des chats.
C’est une affection le plus souvent bénigne. Nous rapportons un cas de
pancréatite aigue dans le décours une toxocarose. |
What is the dbSUPER database? | dbSUPER is the first integrated and interactive database of super-enhancers, with the primary goal of providing a resource for assistance in further studies related to transcriptional control of cell identity and disease. dbSUPER provides a responsive and user-friendly web interface to facilitate efficient and comprehensive search and browsing. The data can be easily sent to Galaxy instances, GREAT and Cistrome web-servers for downstream analysis, and can also be visualized in the UCSC genome browser where custom tracks can be added automatically. The data can be downloaded and exported in variety of formats. Furthermore, dbSUPER lists genes associated with super-enhancers and also links to external databases such as GeneCards, UniProt and Entrez. dbSUPER also provides an overlap analysis tool to annotate user-defined regions. | |
List places in the body where somatostatin is produced. | Somatostatin is a cyclic peptide well known for its strong regulatory effects throughout the body. Also known by the name of growth hormone inhibiting hormone, it is produced in many locations, which include the olfactory bulb, hair follicles, pancreas, retina, and central nervous system (CNS). | The kinetics of insulin, glucagon and somatostatin release was studied in human
pancreatic islets. Batches of 10-15 islets were perifused and the hormones
measured with RIA in 30-sec fractions. Increase of glucose from 3 to 20 mm
resulted in a brief pulse of glucagon coinciding with suppression of basal
insulin and somatostatin release. There was a subsequent drop of glucagon
release concomitant with the appearance of a pronounced pulse of insulin and a
slightly delayed pulse of somatostatin. Continued exposure to 20 mm glucose
generated pulsatile release of the three hormones with 7- to 8-min periods
accounting for 60-70% of the secreted amounts. Glucose caused pronounced
stimulation of average insulin and somatostatin release. However, the nadirs
between the glucagon pulses were lower than the secretion at 3 mm glucose,
resulting in 18% suppression of average release. The repetitive glucagon pulses
were antisynchronous to coincident pulses of insulin and somatostatin. The
resulting greater than 20-fold variations of the insulin to glucagon ratio might
be essential for minute-to-minute regulation of the hepatic glucose production. Immune privilege (IP) is believed to exist in the anagen hair follicle (HF).
Studies have shown that downregulation of major histocompatibility complex Class
I occurs and immunosuppressive factors are expressed in the HF bulb and bulge.
However, demonstration and quantification of functional IP in HF cells are
required. We examined the middle (sheath) and lower (bulb) portions of the human
HF using quantitative real-time RT-PCR (qPCR), immunohistology, ELISA, in vitro
coculture with peripheral blood mononuclear cells (PBMCs), and flow cytometry.
We found that HF cells, relative to non-follicular epidermal cells, failed to
promote allogeneic PBMC proliferation and CD4(+) and CD8(+) IFNγ production. By
qPCR, we found significant downregulation of Class I and Class II HLA alleles in
both the bulb and sheath, and upregulation of multiple immunoregulatory genes.
It is noteworthy that somatostatin (SST) was significantly upregulated relative
to epidermis. By immunohistochemistry, SST was most strongly expressed in the HF
outer root sheath, and, by ELISA, cultured sheath cells secreted SST. PBMCs,
cultured with stimulatory allogeneic epidermal cells and SST, secreted
significantly less IFNγ than controls. Addition of SST antagonists to PBMCs
cocultured with allogeneic HF cells increased IFNγ secretion. The data identify
SST as a secretory factor potentially contributing to the HF IP repertoire. Somatostatin (Som), one of the most concentrated neuropeptides in the brain, is
highly expressed in the olfactory bulb (OB). However, the temporal profile by
which OB somatostatin-expressing (Som+) interneurons are produced and the
molecular mechanisms controlling this profile are totally unknown. In the
present study, we found that all the Som+ interneurons in the mouse external
plexiform layer (EPL) and the rat glomerular layer (GL) express the
transcription factor Sp8.Using the 5-bromo-2'-deoxyuridine (BrdU) birth dating
method, combined with immunostaining, we showed that the generation of Som+
interneurons in the mouse and rat OB is confined to the later embryonic and
earlier postnatal stages. Within the mouse OB, the production of Som+
interneurons is maximal during late embryogenesis and decreases after birth,
whereas the generation of Som+ interneurons is low during embryogenesis and
increases gradually after birth in the rat OB. Interestingly, genetic ablation
of Sp8 by cre/loxP-based recombination severely reduces the number of Som+
interneurons in the EPL of the mouse OB. Taken together, these results suggest
that Sp8 is required for the normal production of Som+ interneurons in the EPL
of the mouse OB. Somatostatin (SST) is a neuromodulator which is abundant throughout the central
nervous system (CNS) and has a crucial role in neurodegenerative disorders.
However, little is known about the effects and mechanisms of SST in dopaminergic
(DA) neurons in the context of Parkinson's disease (PD). In the present study, a
model of PD was generated by injecting lipopolysaccharide (LPS) into the
substantia nigra (SN) of rats in order to investigate the effects of SST on
LPS-induced degeneration of DA in vivo. Intramural injection of LPS resulted in
a significant loss of DA neurons, while reduction of neuronal death by SST
pretreatment was confirmed using immunohistochemical staining for tyrosine
hydroxylase and Nissl. In parallel, immunohistochemical detection of OX-42 and
hydroethidine staining were employed to determine the activation of microglia
and production of reactive oxygen species (ROS), respectively. It was found that
SST inhibited the LPS-induced microglial activity and ROS production. ELISA
revealed a decreased production of pro-inflammatory mediators, including tumor
necrosis factor-α, interleukin-1β and prostaglandin E2 when SST was administered
prior to LPS treatment. Western blot analysis showed that LPS-induced expression
of inducible nitric oxide synthase, cyclooxygenase-2 and nuclear factor κB
(NF-κB) p-p65 was attenuated by administration of SST prior to LPS application.
The results indicated that LPS-induced loss of nigral DA neurons was inhibited
by SST and the observed effects of SST on neuroprotection were associated with
suppression of microglial activation and the NF-κB pathway, ensuing decreases of
neuroinflammation and oxidative stress. The present study therefore suggested
that SST is beneficial for treating neurodegenerative diseases, such as PD,
through inhibiting the activation of microglia. |
Is the Philadelphia chromosome a fusion between parts of chromosomes 1 and 9? | No,
Chronic myeloid leukemia is a stem cell disease with the presence of Philadelphia chromosome generated through reciprocal translocation of chromosome 9 and 22. | Chronic myeloid leukemia is a stem cell disease with the presence of
Philadelphia chromosome generated through reciprocal translocation of chromosome
9 and 22. The use of first- and second-generation tyrosine kinase inhibitors has
been successful to an extent. However, resistance against such drugs is an
emerging problem. Apart from several drug-resistant mechanisms, drug
influx/efflux ratio appears to be one of the key determits of therapeutic
outcomes. In addition, intracellular accumulation of drug critically depends on
cell membrane fluidity and lipid raft dynamics. Previously, we reported two
novel cell-penetrating peptides (CPPs), namely, cationic IR15 and anionic SR11
present in tryptic digest of Abrus agglutinin. Here, the potential of IR15 and
SR11 to influence intracellular concentration of imatinib has been evaluated.
Fluorescent correlation spectroscopy and lifetime imaging were employed to map
membrane fluidity and lipid raft distribution following peptide-drug
co-administration. Results show that IR15 and SR11 are the two CPPs which can
modulate membrane fluidity and lipid raft distribution in K562 cells. Both IR15
and SR11 significantly reduce the viability of CML cells in the presence of
imatinib by increasing the intracellular accumulation of the drug. Chronic myeloid leukemia (CML) is a hematologic maligcy associated with
increased circulating myeloid cells and platelets in the peripheral blood, with
accompanying bone marrow hyperplasia. The Philadelphia chromosome,
t(9;22)(q34;q11), is present in 95% of CML patients, resulting in constitutive
tyrosine kinase activity; however, ~5% of CML patients possess a Philadelphia
variant. A novel three-way Philadelphia translocation variant,
t(9;22;17)(q34;q11.2;q11.2), was identified in a 54-year old man who presented
with leukocytosis, anemia and thrombocytosis that was diagnosed with chronic
myeloid leukemia, chronic phase. Cytogenetic analysis by G-banding revealed the
presence of a three-way translocation involving the long arms of chromosomes 9,
22 and 17. Fluorescence is situ hybridization utilizing a dual-color fusion
probe confirmed the presence of the Bcr-Abl fusion gene. Author information:
(1)Department of Medical Oncology, Hematology Section, National Center for
Cancer Care and Research, Hamad Medical Corporation, Doha, Qatar.
[email protected].
(2)Department of Laboratory Medicine and Pathology, Hamad Medical Corporation,
Doha, Qatar. [email protected].
(3)Department of Medical Education, Internal Medicine Section, Hamad Medical
Corporation, Doha, Qatar. [email protected].
(4)Department of Laboratory Medicine and Pathology, Hamad Medical Corporation,
Doha, Qatar;. [email protected].
(5)Clinical Pathology Department, Faculty of Medicine, AlAzhar University,
Cairo, Egypt. [email protected]. |
What is YESCARTA? | Yescarta is an autologous chimeric antigen receptor (CAR) T cell therapy approved by the FDA. Yescarta™ is approved for the treatment of adult patients with R/R large B cell lymphoma. It is a CD19-specific CAR T cell therapy lysing CD19-positive targets. | Two autologous chimeric antigen receptor (CAR) T cell therapies (Kymriah™ and
Yescarta™) were recently approved by the FDA. Kymriah™ is for the treatment of
pediatric patients and young adults with refractory or relapse (R/R) B cell
precursor acute lymphoblastic leukemia and Yescarta™ is for the treatment of
adult patients with R/R large B cell lymphoma. In common, both are CD19-specific
CAR T cell therapies lysing CD19-positive targets. Their dramatic efficacy in
the short term has been highlighted by many media reports. By contrast, their
glaring safety gaps behind the miracles remain much less addressed. Here, we
focus on addressing the crucial challenges in relation to the gaps. |
What are the 3 types of immunoglobulin heavy chain containing antibodies found in human breast milk? | IgA, IgG, AND IgM can be found in human milk. | BACKGROUND: When feeding preterm infants, donor milk is preferred if the
mother's own milk is unavailable. Pasteurization may have detrimental effects on
bioactivity, but more information is needed about its effects on the
immunological compounds. Research aim: This work has two main aims: evaluate the
antibody profile of colostrum and study the quantitative variations in the
antibodies' level and specific reactivity after undergoing Holder
pasteurization. The authors focused on immunoregulatory components of colostrum
(antidietary antibodies and TGF-β2) in the neonatal gut.
METHODS: This is a descriptive cross-sectional study of a convenience sample of
67 donated colostrum samples at different days after delivery, both raw and
pasteurized. Antibody profiles were analyzed at different times during
breastfeeding, and total and specific antibodies (IgM, IgA, and IgG subclasses)
were compared with tetanus toxoid and ovalbumin using enzyme-linked
immunosorbent assay. The processing effect on total and specific antibodies, as
well as TGF-β2, was evaluated by paired analyses.
RESULTS: No variations in immunological compounds were observed throughout the
colostrum stage. The TGF-β2, antibodies' concentrations, and antibodies'
specific reactivity after pasteurization did not vary significantly as days of
lactation varied. Changes in antibody levels were dependent on isotype and IgG
subclass, and IgG4 showed remarkable resistance to heating. Moreover, the effect
of the pasteurization on specific reactivity was antigen dependent.
CONCLUSION: The supply of relevant immunological components is stable throughout
the colostrum stage. The effects of pasteurization on antibodies depend on
isotype, subclass, and specificity. This information is relevant to improving
the immunological quality of colostrum, especially for preterm newborns. |
What is a exposome? | The exposome is a novel conceptual framework that allows for concurrent examination of multiple intrinsic and extrinsic factors, including environmental exposures, as well as changes in exposures over time, to elucidate the complex environmental factors that affect health outcomes. | SIGNIFICANCE: The environment can elicit biological responses such as oxidative
stress (OS) and inflammation as a consequence of chemical, physical, or
psychological changes. As population studies are essential for establishing
these environment-organism interactions, biomarkers of OS or inflammation are
critical in formulating mechanistic hypotheses. Recent Advances: By using
examples of stress induced by various mechanisms, we focus on the biomarkers
that have been used to assess OS and inflammation in these conditions. We
discuss the difference between biomarkers that are the result of a chemical
reaction (such as lipid peroxides or oxidized proteins that are a result of the
reaction of molecules with reactive oxygen species) and those that represent the
biological response to stress, such as the transcription factor NRF2 or
inflammation and inflammatory cytokines.
CRITICAL ISSUES: The high-throughput and holistic approaches to biomarker
discovery used extensively in large-scale molecular epidemiological exposome are
also discussed in the context of human exposure to environmental stressors.
FUTURE DIRECTIONS: We propose to consider the role of biomarkers as signs and to
distinguish between signs that are just indicators of biological processes and
proxies that one can interact with and modify the disease process. Antioxid.
Redox Signal. 28, 852-872. Author information:
(1)International Agency for Research on Cancer (IARC), 150 Cours Albert-Thomas,
Lyon, 69008, France.
(2)Department of Medical Biotechnology and Translational Medicine, University of
Milan, Milan, Italy.
(3)School of Pharmacy and Life Sciences, The Robert Gordon University, Aberdeen,
United Kingdom.
(4)Gillings School of Global Public Health, UNC, Chapel Hill, NC.
(5)Fels Institute for Cancer Research & Molecular Biology, Philadelphia, PA.
(6)Texas Children's Hospital, Baylor College of Medicine, TX.
(7)University of Arkansas for Medical Sciences, AR.
(8)Aichi Cancer Center Research Institute, Nagoya, Japan.
(9)INSERM, Albert Bonniot Institute, Grenoble, France.
(10)National Cancer Institute (INCA), Rio de Janeiro, Brazil.
(11)Emory University, Atlanta, GA.
(12)Centre for Genomics and Child Health, Blizard Institute, London, United
Kingdom.
(13)Murdoch Childrens Research Institute, Melbourne, Australia.
(14)National Institute of Health, NC.
(15)Statistical Cancer Genomics, UCL Cancer Institute & Dept. of Woman's Cancer,
University College London, United Kingdom.
(16)CAS-MPG Partner Institute for Computational Biology, Shanghai Institute for
Biological Sciences, Shanghai, 200031, China.
(17)National Cancer Center Research Institute, Tokyo, Japan.
(18)MRC/PHE Centre for Environment and Health, School of Public Health, Imperial
College London, London, UK.
(19)Departments of Molecular & Cellular Biology and Medicine, Baylor College of
Medicine, Houston, TX.
(20)Baylor College of Medicine, USDA/ARS Children's Nutrition Research Center,
Houston, TX.
(21)UCSF School of Medicine, Epidemiology & Biostatistics, San Francisco, CA. Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect
almost any organ in the human body. Despite significant advancements in our
understanding of SLE over the recent years, its exact mode of onset and disease
progression remains elusive. Low concordance rates among monozygotic twins with
SLE (as low as 24%), clustering of disease prevalence around polluted regions
and an urban-rural difference in prevalence all highlight the importance of
environmental influences in SLE. Experimental data strongly suggests a complex
interaction between the exposome (or environmental influences) and genome
(genetic material) to produce epigenetic changes (epigenome) that can alter the
expression of genetic material and lead to development of disease in the
susceptible individual. In this review, we focus on the available literature to
explore the role of environmental factors in SLE disease onset and progression
and to better understand the role of exposome-epigenome-genome interactions in
this dreaded disease. BACKGROUND: Acne vulgaris is one of the main reasons for dermatological
consultations. Severity and response to treatment may be impacted by various
external factors or exposome.
AIM: To assess the impact of environmental factors on acne and to provide a
comprehensive overview of the acne exposome.
METHODS: Two consensus meetings of five European dermatologists and a
comprehensive literature search on exposome factors triggering acne served as a
basis for this review.
RESULTS: Acne exposome was defined as the sum of all environmental factors
influencing the occurrence, duration and severity of acne. Exposome factors
impact on the response and the frequency of relapse to treatments by interacting
with the skin barrier, sebaceous gland, innate immunity and cutaneous
microbiota. They may be classified into the following six main categories:
nutrition, psychological and lifestyle factors, occupational factors including
cosmetics, as well as pollutants, medication and climatic factors. Moreover,
practical considerations for the dermatologist's clinical practice are proposed.
CONCLUSION: Exposome factors including nutrition, medication, occupational
factors, pollutants, climatic factors, and psychosocial and lifestyle factors
may impact on the course and severity of acne and on treatment efficacy.
Identifying and reducing the impact of exposome is important for an adequate
acne disease management. 1. |
What does the strimvelis treatment consist of? | Strimvelis consists of autologous CD34+ cells transduced to express adenosine deaminase [ADA]. | BACKGROUND: Strimvelis (autologous CD34+ cells transduced to express adenosine
deaminase [ADA]) is the first ex vivo stem cell gene therapy approved by the
European Medicines Agency (EMA), indicated as a single treatment for patients
with ADA-severe combined immunodeficiency (ADA-SCID) who lack a suitable matched
related bone marrow donor. Existing primary immunodeficiency registries are
tailored to transplantation outcomes and do not capture the breadth of safety
and efficacy endpoints required by the EMA for the long-term monitoring of gene
therapies. Furthermore, for extended monitoring of Strimvelis, the young age of
children treated, small patient numbers, and broad geographic distribution of
patients all increase the risk of loss to follow-up before sufficient data have
been collected. Establishing individual investigator sites would be impractical
and uneconomical owing to the small number of patients from each location
receiving Strimvelis.
RESULTS: An observational registry has been established to monitor the safety
and effectiveness of Strimvelis in up to 50 patients over a minimum of 15 years.
To address the potential challenges highlighted above, data will be collected by
a single investigator site at Ospedale San Raffaele (OSR), Milan, Italy, and
entered into the registry via a central electronic platform. Patients/families
and the patient's local physician will also be able to submit healthcare
information directly to the registry using a uniquely designed electronic
platform. Data entry will be monitored by a Gene Therapy Registry Centre (funded
by GlaxoSmithKline) who will ensure that necessary information is collected and
flows between OSR, the patient/family and the patient's local healthcare
provider.
CONCLUSION: The Strimvelis registry sets a precedent for the safety monitoring
of future gene therapies. A unique, patient-focused design has been implemented
to address the challenges of long-term follow-up of patients treated with gene
therapy for a rare disease. Strategies to ensure data completeness and patient
retention in the registry will help fulfil pharmacovigilance requirements.
Collaboration with partners is being sought to expand from a treatment registry
into a disease registry. Using practical and cost-efficient approaches, the
Strimvelis registry is hoped to encourage further innovation in registry design
within orphan drug development. |
Can therapeutic levels of Vedolizumab be found in the breast milk of nursing mothers following treatment for Inflammatory bowel disease? | vedolizumab can be detected in the breast milk of nursing mothers. although more data are imperative, the concentrations of vedolizumab in breast milk are minute and are therefore unlikely to result in systemic or gastro-intestinal immune-suppression of the infant. | |
What is predicted using SURFY? | surfaceome predictor SURFY, based on machine learning. |