46 research outputs found
Varespladib and cardiovascular events in patients with an acute coronary syndrome: the VISTA-16 randomized clinical trial
IMPORTANCE: Secretory phospholipase A2(sPLA2) generates bioactive phospholipid products implicated in atherosclerosis. The sPLA2inhibitor varespladib has favorable effects on lipid and inflammatory markers; however, its effect on cardiovascular outcomes is unknown. OBJECTIVE: To determine the effects of sPLA2inhibition with varespladib on cardiovascular outcomes. DESIGN, SETTING, AND PARTICIPANTS: A double-blind, randomized, multicenter trial at 362 academic and community hospitals in Europe, Australia, New Zealand, India, and North America of 5145 patients randomized within 96 hours of presentation of an acute coronary syndrome (ACS) to either varespladib (n = 2572) or placebo (n = 2573) with enrollment between June 1, 2010, and March 7, 2012 (study termination on March 9, 2012). INTERVENTIONS: Participants were randomized to receive varespladib (500 mg) or placebo daily for 16 weeks, in addition to atorvastatin and other established therapies. MAIN OUTCOMES AND MEASURES: The primary efficacy measurewas a composite of cardiovascular mortality, nonfatal myocardial infarction (MI), nonfatal stroke, or unstable angina with evidence of ischemia requiring hospitalization at 16 weeks. Six-month survival status was also evaluated. RESULTS: At a prespecified interim analysis, including 212 primary end point events, the independent data and safety monitoring board recommended termination of the trial for futility and possible harm. The primary end point occurred in 136 patients (6.1%) treated with varespladib compared with 109 patients (5.1%) treated with placebo (hazard ratio [HR], 1.25; 95%CI, 0.97-1.61; log-rank P = .08). Varespladib was associated with a greater risk of MI (78 [3.4%] vs 47 [2.2%]; HR, 1.66; 95%CI, 1.16-2.39; log-rank P = .005). The composite secondary end point of cardiovascular mortality, MI, and stroke was observed in 107 patients (4.6%) in the varespladib group and 79 patients (3.8%) in the placebo group (HR, 1.36; 95% CI, 1.02-1.82; P = .04). CONCLUSIONS AND RELEVANCE: In patients with recent ACS, varespladib did not reduce the risk of recurrent cardiovascular events and significantly increased the risk of MI. The sPLA2inhibition with varespladib may be harmful and is not a useful strategy to reduce adverse cardiovascular outcomes after ACS. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01130246. Copyright 2014 American Medical Association. All rights reserved
Cognitive Architecture, Concepts, and Introspection: An Information-Theoretic Solution to the Problem of Phenomenal Consciousness
A Scalable High-Throughput Chemical Synthesizer
A machine that employs a novel reagent delivery technique for biomolecular synthesis has been developed. This machine separates the addressing of individual synthesis sites from the actual process of reagent delivery by using masks placed over the sites. Because of this separation, this machine is both cost-effective and scalable, and thus the time required to synthesize 384 or 1536 unique biomolecules is very nearly the same. Importantly, the mask design allows scaling of the number of synthesis sites without the addition of new valving. Physical and biological comparisons between DNA made on a commercially available synthesizer and this unit show that it produces DNA of similar quality
El Diario de Pontevedra : periódico liberal: Ano XXIV Número 6895 - 1907 abril 13
Abstract Background Facioscapulohumeral muscular dystrophy (FSHD) is in most cases caused by a contraction of the D4Z4 macrosatellite repeat on chromosome 4 (FSHD1) or by mutations in the SMCHD1 or DNMT3B gene (FSHD2). Both situations result in the incomplete epigenetic repression of the D4Z4-encoded retrogene DUX4 in somatic cells, leading to the aberrant expression of DUX4 in the skeletal muscle. In mice, Smchd1 regulates chromatin repression at different loci, having a role in CpG methylation establishment and/or maintenance. Methods To investigate the global effects of harboring heterozygous SMCHD1 mutations on DNA methylation in humans, we combined 450k methylation analysis on mononuclear monocytes from female heterozygous SMCHD1 mutation carriers and unaffected controls with reduced representation bisulfite sequencing (RRBS) on FSHD2 and control myoblast cell lines. Candidate loci were then evaluated for SMCHD1 binding using ChIP-qPCR and expression was evaluated using RT-qPCR. Results We identified a limited number of clustered autosomal loci with CpG hypomethylation in SMCHD1 mutation carriers: the protocadherin (PCDH) cluster on chromosome 5, the transfer RNA (tRNA) and 5S rRNA clusters on chromosome 1, the HOXB and HOXD clusters on chromosomes 17 and 2, respectively, and the D4Z4 repeats on chromosomes 4 and 10. Furthermore, minor increases in RNA expression were seen in FSHD2 myoblasts for some of the PCDHβ cluster isoforms, tRNA isoforms, and a HOXB isoform in comparison to controls, in addition to the previously reported effects on DUX4 expression. SMCHD1 was bound at DNAseI hypersensitivity sites known to regulate the PCDHβ cluster and at the chromosome 1 tRNA cluster, with decreased binding in SMCHD1 mutation carriers at the PCDHβ cluster sites. Conclusions Our study is the first to investigate the global methylation effects in humans resulting from heterozygous mutations in SMCHD1. Our results suggest that SMCHD1 acts as a repressor on a limited set of autosomal gene clusters, as an observed reduction in methylation associates with a loss of SMCHD1 binding and increased expression for some of the loci
Clinically Advanced p38 Inhibitors Suppress DUX4 Expression in Cellular and Animal Models of Facioscapulohumeral Muscular Dystrophy
Increased DUX4 expression during muscle differentiation correlates with decreased SMCHD1 protein levels at D4Z4
Intrinsic epigenetic regulation of the D4Z4 macrosatellite repeat in a transgenic mouse model for FSHD
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118685.pdf (publisher's version ) (Open Access)Facioscapulohumeral dystrophy (FSHD) is a progressive muscular dystrophy caused by decreased epigenetic repression of the D4Z4 macrosatellite repeats and ectopic expression of DUX4, a retrogene encoding a germline transcription factor encoded in each repeat. Unaffected individuals generally have more than 10 repeats arrayed in the subtelomeric region of chromosome 4, whereas the most common form of FSHD (FSHD1) is caused by a contraction of the array to fewer than 10 repeats, associated with decreased epigenetic repression and variegated expression of DUX4 in skeletal muscle. We have generated transgenic mice carrying D4Z4 arrays from an FSHD1 allele and from a control allele. These mice recapitulate important epigenetic and DUX4 expression attributes seen in patients and controls, respectively, including high DUX4 expression levels in the germline, (incomplete) epigenetic repression in somatic tissue, and FSHD-specific variegated DUX4 expression in sporadic muscle nuclei associated with D4Z4 chromatin relaxation. In addition we show that DUX4 is able to activate similar functional gene groups in mouse muscle cells as it does in human muscle cells. These transgenic mice therefore represent a valuable animal model for FSHD and will be a useful resource to study the molecular mechanisms underlying FSHD and to test new therapeutic intervention strategies
Some DUX4-bound repetitive elements are transcriptionally activated by DUX4.
<p>(A) ∼1% of DUX4-bound regions show statistically-significant activation in response to DUX4 in our conservative analysis. We show normalized RNA-seq read counts within an arbitrary distance of 1 kb from DUX4-bound regions (peaks), comparing counts averaged over two myoblast lines that do not express <i>DUX4</i> (x-axis) to counts averaged over two myoblast lines transduced with lentiviral <i>DUX4</i> (y-axis). Only regions with at least 10 reads summed over all four samples are shown, and counts are plotted on a log scale. The 738 regions shown as green points show statistically significant activation in response to DUX4 (≥2-fold activation, FDR-adjusted p-value≤0.1) and the 6 orange points show significant repression (same thresholds). Regions surrounding DUX4-bound repeats are shown as “+” symbols, with dots representing DUX4-bound unique regions. Some regions (“x” symbols) had normalized counts of 0 in one condition and are plotted at an arbitrary low value so they appear on a log-scale. (B) DUX4-bound regions with more predicted DUX4 binding motifs are more likely to be transcriptionally activated. The y-axis value gives the percentage of regions that are transcriptionally activated by DUX4 (≥2-fold, FDR-adjusted p-value≤0.1). (C) DUX4-bound regions with more predicted DUX4 binding motifs have greater DUX4 occupancy, using ChIP-seq peak height as a proxy for DUX4 occupancy (shown on a log-scale).</p