355 research outputs found
Enhanced Integrin α4β1-Mediated Adhesion Contributes to a Mobilization Defect of Endothelial Progenitor Cells in Diabetes.
Diabetes is associated with a deficit of circulating endothelial progenitor cells (EPCs), which has been attributed to their defective mobilization from the bone marrow. The basis for this mobilization defect is not completely understood, and we sought to determine if hyperglycemic conditions enhanced EPC adhesion. We found that culturing EPCs in high glucose media increased adhesion to bone marrow stromal cells. This enhanced adhesion was associated with decreased expression of protein kinase A regulatory subunit 1β (PRKAR1β), activation of protein kinase A (PKA), and phosphorylation of α4-integrin on serine 988. This potentiated adhesion was reversed by treatment with a PKA inhibitor, overexpression of PRKAR1β, or expression of a phosphorylation-defective α4-integrin variant (α4[S988A]). Using a model of type 1 diabetes, we showed that α4(S988A)-expressing mice have more circulating EPCs than their wild-type counterparts. Moreover, diabetic α4(S988A) mice demonstrate enhanced revascularization after hind limb ischemia. Thus, we have identified a novel signaling mechanism activating PKA in diabetes (downregulation of an inhibitory regulatory subunit) that leads to deficits of circulating EPCs and impaired vascular repair, which could be reversed by α4-integrin mutation
Antitumor activity of an anti-CD98 antibody.
CD98 is expressed on several tissue types and specifically upregulated on fast-cycling cells undergoing clonal expansion. Various solid (e.g., nonsmall cell lung carcinoma) as well as hematological malignancies (e.g., acute myeloid leukemia) overexpress CD98. We have identified a CD98-specific mouse monoclonal antibody that exhibits potent preclinical antitumor activity against established lymphoma tumor xenografts. Additionally, the humanized antibody designated IGN523 demonstrated robust tumor growth inhibition in leukemic cell-line derived xenograft models and was as efficacious as standard of care carboplatin in patient-derived nonsmall lung cancer xenografts. In vitro studies revealed that IGN523 elicited strong ADCC activity, induced lysosomal membrane permeabilization and inhibited essential amino acid transport function, ultimately resulting in caspase-3 and -7-mediated apoptosis of tumor cells. IGN523 is currently being evaluated in a Phase I clinical trial for acute myeloid leukemia (NCT02040506). Furthermore, preclinical data support the therapeutic potential of IGN523 in solid tumors
Atrazine and cancer incidence among pesticide applicators in the agricultural health study (1994-2007).
Atrazine is a triazine herbicide used widely in the United States. Although it is an animal carcinogen, the mechanism in rodents does not appear to operate in humans. Few epidemiologic studies have provided evidence for an association
Genetic variation and gene expression across multiple tissues and developmental stages in a non-human primate
By analyzing multitissue gene expression and genome-wide genetic variation data in samples from a vervet monkey pedigree, we generated a transcriptome resource and produced the first catalog of expression quantitative trait loci (eQTLs) in a nonhuman primate model. This catalog contains more genome-wide significant eQTLs per sample than comparable human resources and identifies sex- and age-related expression patterns. Findings include a master regulatory locus that likely has a role in immune function and a locus regulating hippocampal long noncoding RNAs (lncRNAs), whose expression correlates with hippocampal volume. This resource will facilitate genetic investigation of quantitative traits, including brain and behavioral phenotypes relevant to neuropsychiatric disorders
Multi-phase nature of sintered vs. arc-melted CrxAlFeCoNi high entropy alloys - experimental and theoretical study
High entropy CrxAlFeCoNi alloys with x = 0, 0.5, 1.0 and 1.5 were synthesized using arc-melting and sintering preparation techniques. Three crystal structures (fcc, bcc and σ) were observed using XRD technique, while EDX measurements showed the presence of up to three chemically different phases (FeCr-rich phase with fcc structure, AlNi-rich phase with bcc structure and Cr-rich phase with bcc and/or σ structures). The reasons for the observed phase coexistence were addressed to total energy electronic structure calculations using KKR-CPA method accounting for chemical disorder effects. Such theoretical analysis confirmed that the multi-phase system was energetically more favorable than the single-phase one. Furthermore, DSC measurements allowed to identify two phase transitions in melted samples, unlike sintered ones due to high-temperature nitrogen corrosion. This process turned out to be highly selective, resulting in the formation of the scales consisting of AlnNm–phases at the cost of total Al loss in the HEA alloy
Consumer Bankruptcy Update
Materials from the Consumer Bankruptcy Update presentations held by UK/CLE in December 2000
Direct Experimental Constraints on the Spatial Extent of a Neutrino Wavepacket
Despite their high relative abundance in our Universe, neutrinos are the
least understood fundamental particles of nature. They also provide a unique
system to study quantum coherence and the wavelike nature of particles in
fundamental systems due to their extremely weak interaction probabilities. In
fact, the quantum properties of neutrinos emitted in experimentally relevant
sources are virtually unknown and the spatial extent of the neutrino wavepacket
is only loosely constrained by reactor neutrino oscillation data with a spread
of 13 orders of magnitude. Here, we present the first direct limits of this
quantity through a new experimental concept to extract the energy width,
, of the recoil daughter nucleus emitted in the nuclear
electron capture (EC) decay of Be. The final state in the EC decay process
contains a recoiling Li nucleus and an electron neutrino () which
are entangled at their creation. The Li energy spectrum is measured to high
precision by directly embedding Be radioisotopes into a high resolution
superconducting tunnel junction that is operated as a cryogenic sensor. The
lower limit on the spatial uncertainty of the recoil daughter was found to be
\,pm, which implies the final-state system is
localized at a scale more than a thousand times larger than the nucleus itself.
From this measurement, the first direct lower limits on the spatial extent of
the neutrino wavepacket were extracted using two different theoretical methods.
These results have wide-reaching implications in several areas including the
nature of spatial localization at sub-atomic scales, interpretation of neutrino
physics data, and the potential reach of future large-scale experiments.Comment: 20 pages, 3 figures, v3 corrects and updates one of the wavepacket
width calculation
A Deep Catalogue of Protein-Coding Variation in 983,578 Individuals
Rare coding variants that substantially affect function provide insights into the biology of a gene1-3. However, ascertaining the frequency of such variants requires large sample sizes4-8. Here we present a catalogue of human protein-coding variation, derived from exome sequencing of 983,578 individuals across diverse populations. In total, 23% of the Regeneron Genetics Center Million Exome (RGC-ME) data come from individuals of African, East Asian, Indigenous American, Middle Eastern and South Asian ancestry. The catalogue includes more than 10.4 million missense and 1.1 million predicted loss-of-function (pLOF) variants. We identify individuals with rare biallelic pLOF variants in 4,848 genes, 1,751 of which have not been previously reported. From precise quantitative estimates of selection against heterozygous loss of function (LOF), we identify 3,988 LOF-intolerant genes, including 86 that were previously assessed as tolerant and 1,153 that lack established disease annotation. We also define regions of missense depletion at high resolution. Notably, 1,482 genes have regions that are depleted of missense variants despite being tolerant of pLOF variants. Finally, we estimate that 3% of individuals have a clinically actionable genetic variant, and that 11,773 variants reported in ClinVar with unknown significance are likely to be deleterious cryptic splice sites. To facilitate variant interpretation and genetics-informed precision medicine, we make this resource of coding variation from the RGC-ME dataset publicly accessible through a variant allele frequency browser
Evidence for Genetic Overlap Between Schizophrenia and Age at First Birth in Women
ImportanceA recently published study of national data by McGrath et al in 2014 showed increased risk of schizophrenia (SCZ) in offspring associated with both early and delayed parental age, consistent with a U-shaped relationship. However, it remains unclear if the risk to the child is due to psychosocial factors associated with parental age or if those at higher risk for SCZ tend to have children at an earlier or later age.ObjectiveTo determine if there is a genetic association between SCZ and age at first birth (AFB) using genetically informative but independently ascertained data sets.Design, setting, and participantsThis investigation used multiple independent genome-wide association study data sets. The SCZ sample comprised 18 957 SCZ cases and 22 673 controls in a genome-wide association study from the second phase of the Psychiatric Genomics Consortium, and the AFB sample comprised 12 247 genotyped women measured for AFB from the following 4 community cohorts: Estonia (Estonian Genome Center Biobank, University of Tartu), the Netherlands (LifeLines Cohort Study), Sweden (Swedish Twin Registry), and the United Kingdom (TwinsUK). Schizophrenia genetic risk for each woman in the AFB community sample was estimated using genetic effects inferred from the SCZ genome-wide association study.Main outcomes and measuresWe tested if SCZ genetic risk was a significant predictor of response variables based on published polynomial functions that described the relationship between maternal age and SCZ risk in offspring in Denmark. We substituted AFB for maternal age in these functions, one of which was corrected for the age of the father, and found that the fit was superior for the model without adjustment for the father's age.ResultsWe observed a U-shaped relationship between SCZ risk and AFB in the community cohorts, consistent with the previously reported relationship between SCZ risk in offspring and maternal age when not adjusted for the age of the father. We confirmed that SCZ risk profile scores significantly predicted the response variables (coefficient of determination R2 = 1.1E-03, P = 4.1E-04), reflecting the published relationship between maternal age and SCZ risk in offspring by McGrath et al in 2014.Conclusions and relevanceThis study provides evidence for a significant overlap between genetic factors associated with risk of SCZ and genetic factors associated with AFB. It has been reported that SCZ risk associated with increased maternal age is explained by the age of the father and that de novo mutations that occur more frequently in the germline of older men are the underlying causal mechanism. This explanation may need to be revised if, as suggested herein and if replicated in future studies, there is also increased genetic risk of SCZ in older mothers
Whole-genome sequencing reveals host factors underlying critical COVID-19
Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2–4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease
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