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991.
992.
Garrett I. Ash Matthew A. Kostek Harold Lee Theodore J. Angelopoulos Priscilla M. Clarkson Paul M. Gordon Niall M. Moyna Paul S. Visich Robert F. Zoeller Thomas B. Price Joseph M. Devaney Heather Gordish-Dressman Paul D. Thompson Eric P. Hoffman Linda S. Pescatello 《PloS one》2016,11(1)
Glucocorticoid receptor (NR3C1) polymorphisms associate with obesity, muscle strength, and cortisol sensitivity. We examined associations among four NR3C1 polymorphisms and the muscle response to resistance training (RT). European-American adults (n = 602, 23.8±0.4yr) completed a 12 week unilateral arm RT program. Maximum voluntary contraction (MVC) assessed isometric strength (kg) and MRI assessed biceps size (cm2) pre- and post-resistance training. Subjects were genotyped for NR3C1 -2722G>A, -1887G>A, -1017T>C, and +363A>G. Men carrying the -2722G allele gained less relative MVC (17.3±1.2vs33.5±6.1%) (p = 0.010) than AA homozygotes; men with -1887GG gained greater relative MVC than A allele carriers (19.6±1.4vs13.2±2.3%) (p = 0.016). Women carrying the -1017T allele gained greater relative size (18.7±0.5vs16.1±0.9%) (p = 0.016) than CC homozygotes. We found sex-specific NR3C1 associations with the muscle strength and size response to RT. Future studies should investigate whether these associations are partially explained by cortisol’s actions in muscle tissue as they interact with sex differences in cortisol production. 相似文献
993.
Young Kwang Chae Debora de Melo Gagliato Sachin Gopalkrishna Pai Benedito Carneiro Nisha Mohindra Francis Joseph Giles Praveen Ramakrishnan-Geethakumari Joohyuk Sohn Shuying Liu Huiqin Chen Naoto Ueno Gabriel Hortobagyi Ana Maria Gonzalez-Angulo 《PloS one》2016,11(4)
EGFR and cMET cross-talk is involved in breast cancer (BC) progression and resistance to different targeted therapies, however little is known about the co-expression patterns of EGFR and cMET or its prognostic significance in BC. Protein levels of EGFR, cMET and their phosphorylated proteins were measured in 825 BC samples using reverse phase protein array (RPPA). Given unimodal distribution of proteins, the median was selected as a cut-off after sensitivity analyses. Kaplan-Meier survival curves were used to estimate relapse-free (RFS) and overall survival (OS). Cox-proportional hazards models were utilized to determine associations between EGFR and cMET with outcomes. Mean age was 58 years with 457 (55%) hormone receptor (HR) positive, 211 (26%) triple-negative (TN) and 148 (18%) HER2 positive tumors (HER2+). HER2+ was associated with higher EGFR expression and phosphorylation, compared to HR and TN (p<0.05). High EGFR expression was associated with higher phosphorylated-cMET (p-cMET) but not cMET (ANOVA p-cMET p < 0.001; cMET p = 0.34). The same association was found with high phosphorylated-EGFR (p-EGFR) group at Tyr992 and Tyr1068 (both p < 0.001). High expressions in either of two p-EGFRs were linked with higher cMET as well (all p<0.001). For the TN subtype, high expression in EGFR and p-EGFR at Tyr992 but not at Tyr1068 was associated with higher p-cMET (p<0.00, p = 0.012, p = 0.4 respectively). Only high expression in p-EGFR at Tyr992 was linked with higher expression of cMET (p = 0.02). In contrast, among HER2 subtype, high expression in p-EGFR at Tyr1068 but not at Tyr992 was associated with higher cMET and p-cMET (cMET p = 0.023;p-cMET p<0.001). Four subgroups of patients defined by dichotomized EGFR/p-EGFR and cMET/p-cMET level demonstrated no significant differences in survival. In multivariate analyses, neither cMET nor EGFR expression/activation was found to be an independent prognostic factor in survival outcome. 相似文献
994.
Joseph Khoory Jessica Estanislau Abdallah Elkhal Asmae Lazaar Mark I. Melhorn Abigail Brodsky Ben Illigens Itaru Hamachi Yasutaka Kurishita Alexander R. Ivanov Sergey Shevkoplyas Nathan I. Shapiro Ionita C. Ghiran 《PloS one》2016,11(1)
Acute, inflammatory conditions associated with dysregulated complement activation are characterized by significant increases in blood concentration of reactive oxygen species (ROS) and ATP. The mechanisms by which these molecules arise are not fully understood. In this study, using luminometric- and fluorescence-based methods, we show that ligation of glycophorin A (GPA) on human red blood cells (RBCs) results in a 2.1-fold, NADPH-oxidase-dependent increase in intracellular ROS that, in turn, trigger multiple downstream cascades leading to caspase-3 activation, ATP release, and increased band 3 phosphorylation. Functionally, using 2D microchannels to assess membrane deformability, GPS-ligated RBCs travel 33% slower than control RBCs, and lipid mobility was hindered by 10% using fluorescence recovery after photobleaching (FRAP). These outcomes were preventable by pretreating RBCs with cell-permeable ROS scavenger glutathione monoethyl ester (GSH-ME). Our results obtained in vitro using anti-GPA antibodies were validated using complement-altered RBCs isolated from control and septic patients. Our results suggest that during inflammatory conditions, circulating RBCs significantly contribute to capillary flow dysfunctions, and constitute an important but overlooked source of intravascular ROS and ATP, both critical mediators responsible for endothelial cell activation, microcirculation impairment, platelet activation, as well as long-term dysregulated adaptive and innate immune responses. 相似文献
995.
Maria I. Fonseca Shuhui Chu Aimee L. Pierce William D. Brubaker Richard E. Hauhart Diego Mastroeni Elizabeth V. Clarke Joseph Rogers John P. Atkinson Andrea J. Tenner 《PloS one》2016,11(2)
Chronic activation of the complement system and induced inflammation are associated with neuropathology in Alzheimer’s disease (AD). Recent large genome wide association studies (GWAS) have identified single nucleotide polymorphisms (SNPs) in the C3b/C4b receptor (CR1 or CD35) that are associated with late onset AD. Here, anti-CR1 antibodies (Abs) directed against different epitopes of the receptor, were used to localize CR1 in brain, and relative binding affinities of the CR1 ligands, C1q and C3b, were assessed by ELISA. Most Abs tested stained red blood cells in blood vessels but showed no staining in brain parenchyma. However, two monoclonal anti-CR1 Abs labeled astrocytes in all of the cases tested, and this reactivity was preabsorbed by purified recombinant human CR1. Human brain-derived astrocyte cultures were also reactive with both mAbs. The amount of astrocyte staining varied among the samples, but no consistent difference was conferred by diagnosis or the GWAS-identified SNPs rs4844609 or rs6656401. Plasma levels of soluble CR1 did not correlate with diagnosis but a slight increase was observed with rs4844609 and rs6656401 SNP. There was also a modest but statistically significant increase in relative binding activity of C1q to CR1 with the rs4844609 SNP compared to CR1 without the SNP, and of C3b to CR1 in the CR1 genotypes containing the rs6656401 SNP (also associated with the larger isoform of CR1) regardless of clinical diagnosis. These results suggest that it is unlikely that astrocyte CR1 expression levels or C1q or C3b binding activity are the cause of the GWAS identified association of CR1 variants with AD. Further careful functional studies are needed to determine if the variant-dictated number of CR1 expressed on red blood cells contributes to the role of this receptor in the progression of AD, or if another mechanism is involved. 相似文献
996.
Elizabeth Riley Hidefusa Okabe Laura Germine Jeremy Wilmer Michael Esterman Joseph DeGutis 《PloS one》2016,11(11)
Sustained attentional control is critical for everyday tasks and success in school and employment. Understanding gender differences in sustained attentional control, and their potential sources, is an important goal of psychology and neuroscience and of great relevance to society. We used a large web-based sample (n = 21,484, from testmybrain.org) to examine gender differences in sustained attentional control. Our sample included participants from 41 countries, allowing us to examine how gender differences in each country relate to national indices of gender equality. We found significant gender differences in certain aspects of sustained attentional control. Using indices of gender equality, we found that overall sustained attentional control performance was lower in countries with less equality and that there were greater gender differences in performance in countries with less equality. These findings suggest that creating sociocultural conditions which value women and men equally can improve a component of sustained attention and reduce gender disparities in cognition. 相似文献
997.
Kirsty E. Russell Kian Fan Chung Colin J. Clarke Andrew L. Durham Patrick Mallia Joseph Footitt Sebastian L. Johnston Peter J. Barnes Simon R. Hall Karen D. Simpson Malcolm R. Starkey Philip M. Hansbro Ian M. Adcock Coen H. Wiegman 《PloS one》2016,11(1)
Introduction
Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine associated with acute and chronic inflammatory disorders and corticosteroid insensitivity. Its expression in the airways of patients with chronic obstructive pulmonary disease (COPD), a relatively steroid insensitive inflammatory disease is unclear, however.Methods
Sputum, bronchoalveolar lavage (BAL) macrophages and serum were obtained from non-smokers, smokers and COPD patients. To mimic oxidative stress-induced COPD, mice were exposed to ozone for six-weeks and treated with ISO-1, a MIF inhibitor, and/or dexamethasone before each exposure. BAL fluid and lung tissue were collected after the final exposure. Airway hyperresponsiveness (AHR) and lung function were measured using whole body plethysmography. HIF-1α binding to the Mif promoter was determined by Chromatin Immunoprecipitation assays.Results
MIF levels in sputum and BAL macrophages from COPD patients were higher than those from non-smokers, with healthy smokers having intermediate levels. MIF expression correlated with that of HIF-1α in all patients groups and in ozone-exposed mice. BAL cell counts, cytokine mRNA and protein expression in lungs and BAL, including MIF, were elevated in ozone-exposed mice and had increased AHR. Dexamethasone had no effect on these parameters in the mouse but ISO-1 attenuated cell recruitment, cytokine release and AHR.Conclusion
MIF and HIF-1α levels are elevated in COPD BAL macrophages and inhibition of MIF function blocks corticosteroid-insensitive lung inflammation and AHR. Inhibition of MIF may provide a novel anti-inflammatory approach in COPD. 相似文献998.
Christopher D. Zahm Joseph M. Szulczewski Alyssa A. Leystra Terrah J. Paul Olson Linda Clipson Dawn M. Albrecht Malisa Middlebrooks Andrew T. Thliveris Kristina A. Matkowskyj Mary Kay Washington Michael A. Newton Kevin W. Eliceiri Richard B. Halberg 《PloS one》2016,11(2)
A widely accepted paradigm in the field of cancer biology is that solid tumors are uni-ancestral being derived from a single founder and its descendants. However, data have been steadily accruing that indicate early tumors in mice and humans can have a multi-ancestral origin in which an initiated primogenitor facilitates the transformation of neighboring co-genitors. We developed a new mouse model that permits the determination of clonal architecture of intestinal tumors in vivo and ex vivo, have validated this model, and then used it to assess the clonal architecture of adenomas, intramucosal carcinomas, and invasive adenocarcinomas of the intestine. The percentage of multi-ancestral tumors did not significantly change as tumors progressed from adenomas with low-grade dysplasia [40/65 (62%)], to adenomas with high-grade dysplasia [21/37 (57%)], to intramucosal carcinomas [10/23 (43%]), to invasive adenocarcinomas [13/19 (68%)], indicating that the clone arising from the primogenitor continues to coexist with clones arising from co-genitors. Moreover, neoplastic cells from distinct clones within a multi-ancestral adenocarcinoma have even been observed to simultaneously invade into the underlying musculature [2/15 (13%)]. Thus, intratumoral heterogeneity arising early in tumor formation persists throughout tumorigenesis. 相似文献
999.
Makoto Mizuno Atsuyuki Tomizawa Kousaku Ohno Joseph A. Jakubowski Atsuhiro Sugidachi 《PloS one》2016,11(4)
Platelets play pivotal roles in both hemostasis and thrombosis. Although models of intravital platelet imaging are available for thrombosis studies in mice, few are available for rat studies. The present effort aimed to generate fluorescent platelets in rats and assess their dynamics in a rat model of arterial injury. We generated CD41-ZsGreen1 transgenic rats, in which green fluorescence protein ZsGreen1 was expressed specifically in megakaryocytes and thus platelets. The transgenic rats exhibited normal hematological and biochemical values with the exception of body weight and erythroid parameters, which were slightly lower than those of wild-type rats. Platelet aggregation, induced by 20 μM ADP and 10 μg/ml collagen, and blood clotting times were not significantly different between transgenic and wild-type rats. Saphenous arteries of transgenic rats were injured with 10% FeCl3, and the formation of fluorescent thrombi was evaluated using confocal microscopy. FeCl3 caused time-dependent increases in the mean fluorescence intensity of injured arteries of vehicle-treated rats. Prasugrel (3 mg/kg, p.o.), administered 2 h before FeCl3, significantly inhibited fluorescence compared with vehicle-treated rats (4.5 ± 0.4 vs. 14.9 ± 2.4 arbitrary fluorescence units at 30 min, respectively, n = 8, P = 0.0037). These data indicate that CD41-ZsGreen1 transgenic rats represent a useful model for intravital imaging of platelet-mediated thrombus formation and the evaluation of antithrombotic agents. 相似文献
1000.
Lucas J. Cunningham Jessica K. Lingley Lee R. Haines Joseph M. Ndung’u Stephen J. Torr Emily R. Adams 《PLoS neglected tropical diseases》2016,10(2)