50 research outputs found
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Raloxifene prevents stress granule dissolution, impairs translational control and promotes cell death during hypoxia in glioblastoma cells.
Glioblastoma (GBM) is the most common primary malignant brain tumor, and it has a uniformly poor prognosis. Hypoxia is a feature of the GBM microenvironment, and previous work has shown that cancer cells residing in hypoxic regions resist treatment. Hypoxia can trigger the formation of stress granules (SGs), sites of mRNA triage that promote cell survival. A screen of 1120 FDA-approved drugs identified 129 candidates that delayed the dissolution of hypoxia-induced SGs following a return to normoxia. Amongst these candidates, the selective estrogen receptor modulator (SERM) raloxifene delayed SG dissolution in a dose-dependent manner. SG dissolution typically occurs by 15 min post-hypoxia, however pre-treatment of immortalized U251 and U3024 primary GBM cells with raloxifene prevented SG dissolution for up to 2 h. During this raloxifene-induced delay in SG dissolution, translational silencing was sustained, eIF2α remained phosphorylated and mTOR remained inactive. Despite its well-described role as a SERM, raloxifene-mediated delay in SG dissolution was unaffected by co-administration of β-estradiol, nor did β-estradiol alone have any effect on SGs. Importantly, the combination of raloxifene and hypoxia resulted in increased numbers of late apoptotic/necrotic cells. Raloxifene and hypoxia also demonstrated a block in late autophagy similar to the known autophagy inhibitor chloroquine (CQ). Genetic disruption of the SG-nucleating proteins G3BP1 and G3BP2 revealed that G3BP1 is required to sustain the raloxifene-mediated delay in SG dissolution. Together, these findings indicate that modulating the stress response can be used to exploit the hypoxic niche of GBM tumors, causing cell death by disrupting pro-survival stress responses and control of protein synthesis
Evaluation of the selectivity and sensitivity of isoform- and mutation-specific RAS antibodies
Researchers rely largely on antibodies to measure the abundance, activity, and localization of a protein, information that provides critical insight into both normal and pathological cellular functions. However, antibodies are not always reliable or universally valid for the methods in which they are used; in particular, the reliability of commercial antibodies against RAS is highly variable. Waters et al . rigorously assessed 22 commercially available RAS antibodies for their utility to detect the distinct RAS isoforms in various cell types and for their use in specific analytical methods. Their findings show how reliably one can interpret the data acquired from each reagent
Rare coding variants in PLCG2, ABI3, and TREM2 implicate microglial-mediated innate immunity in Alzheimer's disease
We identified rare coding variants associated with Alzheimer’s disease (AD) in a 3-stage case-control study of 85,133 subjects. In stage 1, 34,174 samples were genotyped using a whole-exome microarray. In stage 2, we tested associated variants (P<1×10-4) in 35,962 independent samples using de novo genotyping and imputed genotypes. In stage 3, an additional 14,997 samples were used to test the most significant stage 2 associations (P<5×10-8) using imputed genotypes. We observed 3 novel genome-wide significant (GWS) AD associated non-synonymous variants; a protective variant in PLCG2 (rs72824905/p.P522R, P=5.38×10-10, OR=0.68, MAFcases=0.0059, MAFcontrols=0.0093), a risk variant in ABI3 (rs616338/p.S209F, P=4.56×10-10, OR=1.43, MAFcases=0.011, MAFcontrols=0.008), and a novel GWS variant in TREM2 (rs143332484/p.R62H, P=1.55×10-14, OR=1.67, MAFcases=0.0143, MAFcontrols=0.0089), a known AD susceptibility gene. These protein-coding changes are in genes highly expressed in microglia and highlight an immune-related protein-protein interaction network enriched for previously identified AD risk genes. These genetic findings provide additional evidence that the microglia-mediated innate immune response contributes directly to AD development
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Effects of Emulsion-Based Resonant Infrared Matrix Assisted Pulsed Laser Evaporation (RIR-MAPLE) on the Molecular Weight of Polymers
The molecular weight of a polymer determines key optoelectronic device characteristics, such as internal morphology and charge transport. Therefore, it is important to ensure that polymer deposition techniques do not significantly alter the native polymer molecular weight. This work addresses polymers deposited by resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE). By using a novel emulsion-based target technique, the deposition of smooth, contiguous films with no evidence of chemical degradation have been enabled. However, structural degradation via a reduction in molecular weight remains an open question. The common polymer standard, PMMA, and the optoelectronic polymers, P3HT and MEH-PPV, have been characterized before and after emulsion-based RIR-MAPLE deposition via gel permeation chromatography to determine if RIR-MAPLE affects the deposited polymer molecular weight. Proton nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy measurements have also been conducted to verify the absence of chemical degradation. These measurements verify that there is no chemical degradation of the polymers, and that PMMA and P3HT show no structural degradation, but MEH-PPV exhibits a halving of the weight-averaged molecular weight after RIR-MAPLE deposition. Compared with competing laser deposition techniques, RIR-MAPLE is shown to have the least effect on the molecular weight of the resulting thin films
Emulsion-Based RIR-MAPLE Deposition of Conjugated Polymers: Primary Solvent Effect and Its Implications on Organic Solar Cell Performance
Emulsion-based, resonant
infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) has
been demonstrated as an alternative technique to deposit conjugated
polymer films for photovoltaic applications; yet, a fundamental understanding
of how the emulsion target characteristics translate into film properties
and solar cell performance is unclear. Such understanding is crucial
to enable the rational improvement of organic solar cell (OSC) efficiency
and to realize the expected advantages of emulsion-based RIR-MAPLE
for OSC fabrication. In this paper, the effect of the primary solvent
used in the emulsion target is studied, both experimentally and theoretically,
and it is found to determine the conjugated polymer cluster size in
the emulsion as well as surface roughness and internal morphology
of resulting polymer films. By using a primary solvent with low solubility-in-water
and low vapor pressure, the surface roughness of deposited P3HT and
PCPDTBT polymer films was reduced to 10 nm, and the efficiency of
P3HT:PC<sub>61</sub>BM OSCs was increased to 3.2% (∼100 times
higher compared to the first MAPLE OSC demonstration [Caricato, A. P.; Appl. Phys. Lett. 2012, 100, 073306]). This work unveils the mechanism
of polymer film formation using emulsion-based RIR-MAPLE and provides
insight and direction to determine the best ways to take advantage
of the emulsion target approach to control film properties for different
applications
Torques con extremos en doble escocia y alambre enrollado en el aro - Lan0003
Proyectos del Plan Nacional I+D+I con referencias PB94-0129, PB97-1132, BHA 2002-00138, HUM 2006-06250/HISTProyectos de la CAM con referencias 06/0020/1997, 06/0094/1998, 06/0090/2000, 06/0043/2001Programa Consolider-Ingenio 2010 con sigla CSD2007-00058NoInstituto Valencia de Don JuanLangreoTorques con extremos en doble escocia y alambre enrollado en el ar
Vaccination with toxoid SAg inhibits <i>S. pyogenes</i> nasopharyngeal infection in mice.
<p>(A) Time-line of vaccination protocol. (B) Anti-SpeA IgG antibody titres (mean ± SEM) from HLA-B6 mice (n = 5 mice per group), either sham vaccinated, or vaccinated with SpeA<sub>Y100A</sub> as described in <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1004155#s4" target="_blank">Materials and Methods</a>. (C) Sham or SpeA<sub>Y100A</sub> vaccinated HLA-B6 mice were nasally inoculated with ∼1×10<sup>8</sup> bacterial CFUs of <i>S. pyogenes</i> MGAS8232. Nasopharyngeal CFUs were assessed at 48 h. Each symbol represents an individual mouse. Statistical significance is displayed as **<i>p</i><0.01 by Student's <i>t</i>-test.</p