275 research outputs found
Initial Vibration Analysis of the Advanced Stirling Radioisotope Generator's (ASRG's) Affect on Spacecraft Instruments
Assess if nominal Advanced Stirling Radioisotope Generator (ASRG)
vibration levels are sufficiently benign for unimpeded spacecraft
instrument operation
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Vitamin D-responsive SGPP2 variants associated with lung cell expression and lung function
Background: Vitamin D is associated with lung health in epidemiologic studies, but mechanisms mediating observed associations are poorly understood. This study explores mechanisms for an effect of vitamin D in lung through an in vivo gene expression study, an expression quantitative trait loci (eQTL) analysis in lung tissue, and a population-based cohort study of sequence variants. Methods: Microarray analysis investigated the association of gene expression in small airway epithelial cells with serum 25(OH)D in adult non-smokers. Sequence variants in candidate genes identified by the microarray were investigated in a lung tissue eQTL database, and also in relation to cross-sectional pulmonary function in the Health, Aging, and Body Composition (Health ABC) study, stratified by race, with replication in the Framingham Heart Study (FHS). Results: 13 candidate genes had significant differences in expression by serum 25(OH)D (nominal p < 0.05), and a genome-wide significant eQTL association was detected for SGPP2. In Health ABC, SGPP2 SNPs were associated with FEV1 in both European- and African-Americans, and the gene-level association was replicated in European-American FHS participants. SNPs in 5 additional candidate genes (DAPK1, FSTL1, KAL1, KCNS3, and RSAD2) were associated with FEV1 in Health ABC participants. Conclusions: SGPP2, a sphingosine-1-phosphate phosphatase, is a novel vitamin D-responsive gene associated with lung function. The identified associations will need to be followed up in further studies
Specific micronutrient concentrations are associated with inflammatory cytokines in a rural population of Mexican women with a high prevalence of obesity
It has been recognised recently that obese individuals have lower concentrations of micronutrients and this may affect the concentrations of inflammatory cytokines. A cross-sectional study was carried out to evaluate the association of specific micronutrients' status with chronic inflammation caused by obesity in 280 women (36·1 (sd 7·5) years) from seven rural communities in Mexico. Measurements of weight, height and waist circumference were made on all women and body composition was determined by dual-energy X-ray absorptiometry. Concentrations of the cytokines IL-1, TNF-α, IL-6, IL-10 and IL-12, lipid profile, and the micronutrients Zn and vitamins A, C and E were determined in fasting blood samples. Ordered logistic regression models were used to determine associations between categorised cytokine levels and micronutrients. It was found that 80 % of women were overweight or obese, and had significantly higher concentrations of C-reactive protein than normal-weight women (P = 0·05). The risk of higher levels of TNF-α, IL-6, IL-10 and IL-12 was reduced significantly among women with higher Zn concentrations (OR 0·63, 95 % CI 0·42, 0·96, P = 0·03; OR 0·57, 95 % CI 0·39, 0·86, P = 0·025; OR 0·63, 95 % CI 0·41, 0·96, P = 0·04; OR 0·62, 95 % CI 0·41, 0·95, P = 0·03, respectively). Higher concentrations of vitamin A were slightly associated with reduced risks of higher levels of IL-1 and IL-12 (OR 0·97, 95 % CI 0·95, 0·99, P = 0·03; OR 0·97, 95 % CI 0·94, 0·99, P = 0·03, respectively); when adjusting for BMI, this association was lost. No associations were found between vitamin C or vitamin E:lipids concentrations and inflammatory cytokines. In conclusion, higher Zn concentrations are associated with reduced risks of higher concentration of inflammation markers in a population of women with a high prevalence of obesity
In search of novel immune-modulatory compounds from British Columbia wild mushrooms and their effectiveness in inflammatory micro-circulation of mice
Natural products have been an integral component of people's health and health outcomes for thousands of years. In particular, several mushroom species have demonstrated beneficial therapeutic potential. The goals of this research are to explore the immune-stimulatory and anti-inflammatory potential of wild mushrooms native to the North Central region of British Columbia. Out of 42 mushroom extracts examined, four exhibited strong immune-stimulatory activity as assessed by induction of tumor-necrosis factor alpha (TNF-a) production in macrophage cells. Out of thirty-three extracts tests, nineteen demonstrated potent anti-inflammatory activity as determined by inhibition of lipopolysaccharide-induced TNF-a production in macrophage cells. Sodium hydroxide extract of Echinodontium trinctorium exhibited potent anti-inflammatory activity and was selected for further study. A small molecular weight (~5-25 kDa) carbohydrate was successfully purified using sequential size-exclusion and ion-exchange chromatography. GC-MS analysis showed that the polysaccharide has glucose (89.7%) as the major back-bone monosaccharide, and also the presence of other monosaccharides such as mannose (3.1%), galactose (2.8%), fucose (2.4%), and xylose (2.0%). The study also revealed the presence of 1,3-linked glucose linkages. Both the semi-purified anti-inflammatory compound(s) from E. tinctorium and the methanol extract of Inonotus obliquus can ameliorate histamine-induced vasodilation in the 2A arterioles (gluteus maximus muscle) in mice. This is the first study to demonstrate the anti-inflammatory activity of purified compounds and extracts from mushroom in an animal microcirculation model using intravital microscopy
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Refining the accuracy of validated target identification through coding variant fine-mapping in type 2 diabetes.
We aggregated coding variant data for 81,412 type 2 diabetes cases and 370,832 controls of diverse ancestry, identifying 40 coding variant association signals (P < 2.2 × 10-7); of these, 16 map outside known risk-associated loci. We make two important observations. First, only five of these signals are driven by low-frequency variants: even for these, effect sizes are modest (odds ratio ≤1.29). Second, when we used large-scale genome-wide association data to fine-map the associated variants in their regional context, accounting for the global enrichment of complex trait associations in coding sequence, compelling evidence for coding variant causality was obtained for only 16 signals. At 13 others, the associated coding variants clearly represent 'false leads' with potential to generate erroneous mechanistic inference. Coding variant associations offer a direct route to biological insight for complex diseases and identification of validated therapeutic targets; however, appropriate mechanistic inference requires careful specification of their causal contribution to disease predisposition
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Multi-ancestry study of blood lipid levels identifies four loci interacting with physical activity.
Many genetic loci affect circulating lipid levels, but it remains unknown whether lifestyle factors, such as physical activity, modify these genetic effects. To identify lipid loci interacting with physical activity, we performed genome-wide analyses of circulating HDL cholesterol, LDL cholesterol, and triglyceride levels in up to 120,979 individuals of European, African, Asian, Hispanic, and Brazilian ancestry, with follow-up of suggestive associations in an additional 131,012 individuals. We find four loci, in/near CLASP1, LHX1, SNTA1, and CNTNAP2, that are associated with circulating lipid levels through interaction with physical activity; higher levels of physical activity enhance the HDL cholesterol-increasing effects of the CLASP1, LHX1, and SNTA1 loci and attenuate the LDL cholesterol-increasing effect of the CNTNAP2 locus. The CLASP1, LHX1, and SNTA1 regions harbor genes linked to muscle function and lipid metabolism. Our results elucidate the role of physical activity interactions in the genetic contribution to blood lipid levels
Large-scale genome-wide association studies and meta-analyses of longitudinal change in adult lung function.
BACKGROUND: Genome-wide association studies (GWAS) have identified numerous loci influencing cross-sectional lung function, but less is known about genes influencing longitudinal change in lung function.
METHODS: We performed GWAS of the rate of change in forced expiratory volume in the first second (FEV1) in 14 longitudinal, population-based cohort studies comprising 27,249 adults of European ancestry using linear mixed effects model and combined cohort-specific results using fixed effect meta-analysis to identify novel genetic loci associated with longitudinal change in lung function. Gene expression analyses were subsequently performed for identified genetic loci. As a secondary aim, we estimated the mean rate of decline in FEV1 by smoking pattern, irrespective of genotypes, across these 14 studies using meta-analysis.
RESULTS: The overall meta-analysis produced suggestive evidence for association at the novel IL16/STARD5/TMC3 locus on chromosome 15 (P  =  5.71 × 10(-7)). In addition, meta-analysis using the five cohorts with ≥3 FEV1 measurements per participant identified the novel ME3 locus on chromosome 11 (P  =  2.18 × 10(-8)) at genome-wide significance. Neither locus was associated with FEV1 decline in two additional cohort studies. We confirmed gene expression of IL16, STARD5, and ME3 in multiple lung tissues. Publicly available microarray data confirmed differential expression of all three genes in lung samples from COPD patients compared with controls. Irrespective of genotypes, the combined estimate for FEV1 decline was 26.9, 29.2 and 35.7 mL/year in never, former, and persistent smokers, respectively.
CONCLUSIONS: In this large-scale GWAS, we identified two novel genetic loci in association with the rate of change in FEV1 that harbor candidate genes with biologically plausible functional links to lung function
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