192 research outputs found

    Biosynthesis of Triglyceride and Other Fatty Acyl Esters by Developing Rat Brain

    Full text link
    The biosynthesis of triglyceride from 1,2-diglyceride and long-chain acyl coenzyme A (CoA) was studied in developing rat brain. Diglyceride acyltransferase activity was highest in a microsomal fraction, had a neutral pH optimum, and was stimulated by MgCl 2 . Palmitoyl CoA and oleoyl CoA served equally well as acyl donors. The enzyme catalyzed the acylation of both endogenous diglyceride and several naturally occurring and synthetic exogenous diglycerides. In addition, short-chain primary and secondary alcohols were found to be acylated under these conditions. A second acylation system, active at low pH, was found to catalyze esterification of ethanol and cholesterol, but not diglyceride, with free fatty acid. These results demonstrate that brain has the capacity to acylate a wide variety of physiological and nonphysiological hydroxyl compounds.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66158/1/j.1471-4159.1984.tb12842.x.pd

    TOPOGRAPHICAL DISTRIBUTION OF LIPID BIOSYNTHETIC ENZYMES ON PEROXISOMES (MICROBODIES)

    Full text link
    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72338/1/j.1749-6632.1982.tb21437.x.pd

    Impact of Chromogranin A deficiency on catecholamine storage, catecholamine granule morphology and chromaffin cell energy metabolism in vivo

    Get PDF
    Chromogranin A (CgA) is a prohormone and granulogenic factor in neuroendocrine tissues with a regulated secretory pathway. The impact of CgA depletion on secretory granule formation has been previously demonstrated in cell culture. However, studies linking the structural effects of CgA deficiency with secretory performance and cell metabolism in the adrenomedullary chromaffin cells in vivo have not previously been reported. Adrenomedullary content of the secreted adrenal catecholamines norepinephrine (NE) and epinephrine (EPI) was decreased 30–40 % in Chga-KO mice. Quantification of NE and EPI-storing dense core (DC) vesicles (DCV) revealed decreased DCV numbers in chromaffin cells in Chga-KO mice. For both cell types, the DCV diameter in Chga-KO mice was less (100–200 nm) than in WT mice (200–350 nm). The volume density of the vesicle and vesicle number was also lower in Chga-KO mice. Chga-KO mice showed an ~47 % increase in DCV/DC ratio, implying vesicle swelling due to increased osmotically active free catecholamines. Upon challenge with 2 U/kg insulin, there was a diminution in adrenomedullary EPI, no change in NE and a very large increase in the EPI and NE precursor dopamine (DA), consistent with increased catecholamine biosynthesis during prolonged secretion. We found dilated mitochondrial cristae, endoplasmic reticulum and Golgi complex, as well as increased synaptic mitochondria, synaptic vesicles and glycogen granules in Chga-KO mice compared to WT mice, suggesting that decreased granulogenesis and catecholamine storage in CgA-deficient mouse adrenal medulla is compensated by increased VMAT-dependent catecholamine update into storage vesicles, at the expense of enhanced energy expenditure by the chromaffin cell

    Giving RSEs a Larger Stage through the Better Scientific Software Fellowship

    Full text link
    The Better Scientific Software Fellowship (BSSwF) was launched in 2018 to foster and promote practices, processes, and tools to improve developer productivity and software sustainability of scientific codes. BSSwF's vision is to grow the community with practitioners, leaders, mentors, and consultants to increase the visibility of scientific software production and sustainability. Over the last five years, many fellowship recipients and honorable mentions have identified as research software engineers (RSEs). This paper provides case studies from several of the program's participants to illustrate some of the diverse ways BSSwF has benefited both the RSE and scientific communities. In an environment where the contributions of RSEs are too often undervalued, we believe that programs such as BSSwF can be a valuable means to recognize and encourage community members to step outside of their regular commitments and expand on their work, collaborations and ideas for a larger audience.Comment: submitted to Computing in Science & Engineering (CiSE), Special Issue on the Future of Research Software Engineers in the U

    Relations between plasma microRNAs, echocardiographic markers of atrial remodeling, and atrial fibrillation: Data from the Framingham Offspring study

    Get PDF
    BACKGROUND: Circulating microRNAs may reflect or influence pathological cardiac remodeling and contribute to atrial fibrillation (AF). OBJECTIVE: The purpose of this study was to identify candidate plasma microRNAs that are associated with echocardiographic phenotypes of atrial remodeling, and incident and prevalent AF in a community-based cohort. METHODS: We analyzed left atrial function index (LAFI) of 1788 Framingham Offspring 8 participants. We quantified expression of 339 plasma microRNAs. We examined associations between microRNA levels with LAFI and prevalent and incident AF. We constructed pathway analysis of microRNAs\u27 predicted gene targets to identify molecular processes involved in adverse atrial remodeling in AF. RESULTS: The mean age of the participants was 66 +/- 9 years, and 54% were women. Five percent of participants had prevalent AF at the initial examination and 9% (n = 157) developed AF over a median 8.6 years of follow-up (IQR 8.1-9.2 years). Plasma microRNAs were associated with LAFI (N = 73, p \u3c 0.0001). Six of these plasma microRNAs were significantly associated with incident AF, including 4 also associated with prevalent AF (microRNAs 106b, 26a-5p, 484, 20a-5p). These microRNAs are predicted to regulate genes involved in cardiac hypertrophy, inflammation, and myocardial fibrosis. CONCLUSIONS: Circulating microRNAs 106b, 26a-5p, 484, 20a-5p are associated with atrial remodeling and AF

    Extent of podoconiosis-related stigma in Wolaita Zone, Southern Ethiopia: a cross-sectional study

    Get PDF
    Studies have indicated that social stigma related to podoconiosis (endemic non-filarial elephantiasis) has a major impact on the psychosocial wellbeing of patients. However, little effort has been made so far to quantify the level of both felt and enacted stigma in a range of domains of life. We used a recently developed podoconiosis stigma assessment scale to measure levels of stigma as recalled over the previous 12 months. One hundred and fifty patients with podoconiosis rated the levels of stigma they perceived and experienced in 'interpersonal interactions', 'major life areas' and 'community, social and civic life'. High levels of stigma were observed on both felt and enacted stigma scales. The overall average stigma score was 40.7 (range 0 to 96). Enacted stigma was scored higher than felt stigma (mean score 21.2 vs. 19.5, respectively). The mean enacted stigma score was higher in 'major life areas', and 'community, social and civic life' than 'interpersonal interactions', while felt stigma was experienced most at the interpersonal level. Over half of patients reported that they had considered suicide in response to discrimination and prejudice, particularly in interpersonal interactions. Forced divorce, dissolution of marriage plan, insults and exclusion at social events were some of the most commonly mentioned forms of enacted stigma reported by affected individuals. Scores for overall level of stigma and enacted stigma increased significantly with stage of podoconiosis while the association observed in relation to felt stigma was only marginally significant (p = 0.085). Appropriate stigma reduction strategies must be identified and implemented in communities highly endemic for podoconiosis

    Corrosion behaviour of Mg–Zn–Y–Mischmetal alloys in phosphate buffer saline solution

    Full text link
    The influence of the processing route and chemical composition in the corrosion behaviour of two Mg-Zn-Y-Mischmetal alloys has been evaluated in phosphate buffer saline solution. The corrosion resistance of the alloy processed by conventional techniques was substantially higher than that found for the same alloy processed from atomised powders. Fine homogeneous distribution of the second-phase particles promoted severe attack due to the enhanced number of galvanic microcells. A higher concentration of zinc and a lower content of rare earth additions improved the corrosion resistance of the alloys due to the lower volume fraction of second-phase particles. © 2012 Elsevier Ltd.Peer Reviewe

    Defining Global Gene Expression Changes of the Hypothalamic-Pituitary-Gonadal Axis in Female sGnRH-Antisense Transgenic Common Carp (Cyprinus carpio)

    Get PDF
    BACKGROUND: The hypothalamic-pituitary-gonadal (HPG) axis is critical in the development and regulation of reproduction in fish. The inhibition of neuropeptide gonadotropin-releasing hormone (GnRH) expression may diminish or severely hamper gonadal development due to it being the key regulator of the axis, and then provide a model for the comprehensive study of the expression patterns of genes with respect to the fish reproductive system. METHODOLOGY/PRINCIPAL FINDINGS: In a previous study we injected 342 fertilized eggs from the common carp (Cyprinus carpio) with a gene construct that expressed antisense sGnRH. Four years later, we found a total of 38 transgenic fish with abnormal or missing gonads. From this group we selected the 12 sterile females with abnormal ovaries in which we combined suppression subtractive hybridization (SSH) and cDNA microarray analysis to define changes in gene expression of the HPG axis in the present study. As a result, nine, 28, and 212 genes were separately identified as being differentially expressed in hypothalamus, pituitary, and ovary, of which 87 genes were novel. The number of down- and up-regulated genes was five and four (hypothalamus), 16 and 12 (pituitary), 119 and 93 (ovary), respectively. Functional analyses showed that these genes involved in several biological processes, such as biosynthesis, organogenesis, metabolism pathways, immune systems, transport links, and apoptosis. Within these categories, significant genes for neuropeptides, gonadotropins, metabolic, oogenesis and inflammatory factors were identified. CONCLUSIONS/SIGNIFICANCE: This study indicated the progressive scaling-up effect of hypothalamic sGnRH antisense on the pituitary and ovary receptors of female carp and provided comprehensive data with respect to global changes in gene expression throughout the HPG signaling pathway, contributing towards improving our understanding of the molecular mechanisms and regulative pathways in the reproductive system of teleost fish
    corecore