Publications by authors named "Welsh D"

Idiopathic pulmonary arterial hypertension (IPAH) is an incurable condition leading to right ventricular failure and death and inflammation is postulated to be associated with vascular remodelling. Interleukin (IL)-33, a member of the "alarmin" family can either act on the membrane ST2 receptor or as a nuclear repressor, to regulate inflammation. We show, using immunohistochemistry, that IL-33 expression is nuclear in the vessels of healthy subjects whereas nuclear IL-33 is markedly diminished in the vessels of IPAH patients.

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Objective: The gut microbiome has been implicated in obesity and metabolic syndrome; however, most studies have focused on fecal or colonic samples. Several species of Artemisia have been reported to ameliorate insulin signaling both in vitro and in vivo. The aim of this study was to characterize the mucosal and luminal bacterial populations in the terminal ileum with or without supplementation with Artemisia extracts.

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Although research has increasingly emphasized how adolescent sexual behavior may be associated with aspects of health beyond unwanted pregnancy and sexually transmitted infections, no current theoretical or conceptual model fully explains associations between sexual behavior and multiple facets of health. We provide a conceptual model that explicates possible processes of how adolescent sexual behavior may influence physical, mental, and social health. Next, we review the current literature consistent with this conceptual model, demonstrating that although early sexual behavior can be associated with some negative outcomes, sex may be, on average, a positive experience in late adolescence.

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Background: Chronic alcohol intoxication suppresses immune function and increases osteoporosis risk suggesting bone-tissue cytotoxicity. Human immunodeficiency virus infection leads to similar impairments. This study investigated the effects of chronic alcohol administration during the early stage of simian immunodeficiency virus (SIV) infection on hematopoietic stem and progenitor cells (HSPCs) and their differentiated progeny in the bone marrow and peripheral blood of rhesus macaques.

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Dysfunctional electrical signalling within the arteriolar wall is a major cause of cardiovascular disease. The endothelial cell layer constitutes the primary electrical pathway, co-ordinating contraction of the overlying smooth muscle cell (SMC) layer. As myoendothelial gap junctions (MEGJs) provide direct contact between the cell layers, proper vasomotor responses are thought to depend on a high, uniform MEGJ density.

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Many recent corporate scandals have been described as resulting from a slippery slope in which a series of small infractions gradually increased over time (e.g., McLean & Elkind, 2003).

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Many studies have described alternatives to the BOD5 standard method, with substantial decreases in incubation time observed. However, most of these have not maintained the features that make the BOD5 assay so relevant - a high level of substrate bio-oxidation and use of wastewater treatment plant (WWTP) sludge as the biocatalyst. Two recently described ferricyanide-mediated (FM)-BOD assays, one for trade wastes and one for WWTP influents and treated effluents, satisfy these criteria and were investigated further here for their suitability for use with diverse biocatalysts.

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In animals, circadian rhythms in physiology and behavior result from coherent rhythmic interactions between clocks in the brain and those throughout the body. Despite the many tissue specific clocks, most understanding of the molecular core clock mechanism comes from studies of the suprachiasmatic nuclei (SCN) of the hypothalamus and a few other cell types. Here we report establishment and genetic characterization of three cell-autonomous mouse clock models: 3T3 fibroblasts, 3T3-L1 adipocytes, and MMH-D3 hepatocytes.

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An association between circadian clock function and mood regulation is well established and has been proposed as a factor in the development of mood disorders. Patients with depression or mania suffer disturbed sleep-wake cycles and altered rhythms in daily activities. Environmentally disrupted circadian rhythms increase the risk of mood disorders in the general population.

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Background: Although Veterans Affairs (VA) hospitals have been smoke-free inside of buildings since 1991, smoke-free campuses have not been initiated. The purpose of this article is to describe staff attitudes regarding making the VA hospital a smoke-free campus except for the mandated smoking shelters.

Methods: In 2008, a cross-sectional, anonymous survey was conducted with a convenience sample of employees at a Midwestern VA (N = 397).

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Employees are getting less sleep, which has been shown to deplete self-regulatory resources and increase unethical behavior (Barnes, Schaubroeck, Huth, & Ghumman, 2011; Christian & Ellis, 2011). In this study, we extend the original mediated model by examining the role of 2 moderators in the relationship between sleep deprivation, depletion, and deceptive behavior. First, we derive psychological arguments from the psychopharmacology literature to hypothesize that caffeine moderates the relationship between sleep deprivation and depletion by replenishing self-regulatory resources.

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Effects of tobacco smoke on hematologic derangements have received little attention. This study employed a mouse model of cigarette smoke exposure to explore the effects on bone marrow niche function. While lung cancer is the most widely studied consequence of tobacco smoke exposure, other malignancies, including leukemia, are associated with tobacco smoke exposure.

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Modern microbial mats are highly complex and dynamic ecosystems. Diffusive equilibration in thin films (DET) and diffusive gradients in thin films (DGT) samplers were deployed in a modern smooth microbial mat from Shark Bay in order to observe, for the first time, two-dimensional distributions of porewater solutes during day and night time. Two-dimensional sulfide and alkalinity distributions revealed a strong spatial heterogeneity and a minor contribution of sulfide to alkalinity.

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A new diffusive gradients in thin films (DGT) technique with a mixed binding layer (Chelex-100 and the titanium dioxide based adsorbent Metsorb) is described for the simultaneous measurement of labile trace metal (Mn, Co, Ni, Cu, Cd, and Pb) and oxyanion (V, As, Mo, Sb, W, and P) concentrations in freshwater and seawater. The mixed binding layer (MBL) DGT technique was evaluated against the Chelex-DGT and Metsorb-DGT techniques, and all elution efficiencies and diffusion coefficients have been remeasured for the above analytes. Diffusion coefficients (D) measured using MBL-DGT generally agreed well with those measured by Chelex-DGT (DMBL/DChelex = 0.

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Recent reports have noted that T-type Ca2+ channels (CaV3.x) are expressed in vascular smooth muscle and are potential targets of regulation. In this study, we examined whether and by what mechanism nitric oxide (NO), a key vasodilator, influences this conductance.

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Previously, we showed that FI34, a frailty index based on 34 health and function ability variables, is heritable and a reliable phenotypic indicator of healthy aging. We have now examined the relationship between major components of energy expenditure and the FI34 in participants of the Louisiana Healthy Aging Study. Resting metabolic rate was associated with FI34, even after adjustment for fat-free mass, fat mass, age, sex, thyroid hormones, and insulin-like growth factor 1 levels, in multiple regression analyses.

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Objectives: Substantial evidence indicates that depressed participants perform more poorly than nondepressed participants on a number of memory tasks. Cognitive deficits associated with depression (i.e.

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Restructuring of long-term care in Western Health, a regional health authority within Newfoundland and Labrador, created a unique opportunity to study the widespread impacts of the transition. Staff and long-term-care residents were relocated from a variety of settings to a newly constructed facility. A plan was developed to assess the impact of relocation on staff, residents, and families.

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Hypoxia can be defined as a reduction in available oxygen, whether in a whole organism or in a tissue or cell. It is a real life cause of pulmonary hypertension in humans both in terms of patients with chronic hypoxic lung disease and people living at high altitude. The effect of hypoxia on the pulmonary vasculature can be described in two ways; Hypoxic pulmonary vasoconstriction (HPV) (resulting from smooth muscle cell contraction) and pulmonary vascular remodelling (PVR) (resulting from pulmonary vascular cell proliferation).

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Like neurons in the suprachiasmatic nucleus (SCN), the master circadian pacemaker in the brain, single fibroblasts can function as independent oscillators. In the SCN, synaptic and paracrine signaling among cells creates a robust, synchronized circadian oscillation, whereas there is no evidence for such integration in fibroblast cultures. However, interactions among single-cell fibroblast oscillators cannot be completely excluded, because fibroblasts were not isolated in previous work.

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Recent investigations have identified that T-type Ca(2+) channels (CaV3.x) are expressed in rat cerebral arterial smooth muscle. In the study reported here, we isolated the T-type conductance, differentiated the current into the CaV3.

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A titanium dioxide-based DGT method (Metsorb-DGT) was evaluated for the measurement of As(V), V(V), Sb(V), Mo(VI), W(VI) and dissolved reactive phosphorus (DRP) in synthetic waters. Mass vs. time DGT deployments at pH 6.

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Despite the increased attention paid to biases attributable to common method variance (CMV) over the past 50 years, researchers have only recently begun to systematically examine the effect of specific sources of CMV in previously published empirical studies. Our study contributes to this research by examining the extent to which common rater, item, and measurement context characteristics bias the relationships between organizational citizenship behaviors and performance evaluations using a mixed-effects analytic technique. Results from 173 correlations reported in 81 empirical studies (N = 31,146) indicate that even after controlling for study-level factors, common rater and anchor point number similarity substantially biased the focal correlations.

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We report the synthesis of four different RGD peptide derivatives which spontaneously self-assemble into nanoscale architectures. Depending on the information programmed into the molecular-scale building blocks by organic synthesis, these compounds assemble into different nanoscale morphologies. This process can be fully understood using multiscale modelling which provides predictive insight into subtle differences, such as whether the compounds form spherical micelles, rod-like cylinders or tubular assemblies, and predicts experimentally observed critical aggregation concentrations (CACs).

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