961 research outputs found

    Electrophysiological properties of human beta-cell lines EndoC-ÎČH1 and -ÎČH2 conform with human beta-cells

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    © The Author(s) 2018Limited access to human islets has prompted the development of human beta cell models. The human beta cell lines EndoC-ÎČH1 and EndoC-ÎČH2 are increasingly used by the research community. However, little is known of their electrophysiological and secretory properties. Here, we monitored parameters that constitute the glucose-triggering pathway of insulin release. Both cell lines respond to glucose (6 and 20 mM) with 2- to 3-fold stimulation of insulin secretion which correlated with an elevation of [Ca2+]i, membrane depolarisation and increased action potential firing. Similar to human primary beta cells, KATP channel activity is low at 1 mM glucose and is further reduced upon increasing glucose concentration; an effect that was mimicked by the KATP channel blocker tolbutamide. The upstroke of the action potentials reflects the activation of Ca2+ channels with some small contribution of TTX-sensitive Na+ channels. The repolarisation involves activation of voltage-gated Kv2.2 channels and large-conductance Ca2+-activated K+ channels. Exocytosis presented a similar kinetics to human primary beta cells. The ultrastructure of these cells shows insulin vesicles composed of an electron-dense core surrounded by a thin clear halo. We conclude that the EndoC-ÎČH1 and -ÎČH2 cells share many features of primary human ÎČ-cells and thus represent a useful experimental model.Peer reviewedFinal Published versio

    Child and adolescent psychiatric patients and later criminality

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    <p>Abstract</p> <p>Background</p> <p>Sweden has an extensive child and adolescent psychiatric (CAP) research tradition in which longitudinal methods are used to study juvenile delinquency. Up to the 1980s, results from descriptions and follow-ups of cohorts of CAP patients showed that children's behavioural disturbances or disorders and school problems, together with dysfunctional family situations, were the main reasons for families, children, and youth to seek help from CAP units. Such factors were also related to registered criminality and registered alcohol and drug abuse in former CAP patients as adults. This study investigated the risk for patients treated 1975–1990 to be registered as criminals until the end of 2003.</p> <p>Methods</p> <p>A regional sample of 1,400 former CAP patients, whose treatment occurred between 1975 and 1990, was followed to 2003, using database-record links to the Register of Persons Convicted of Offences at the National Council for Crime Prevention (NCCP).</p> <p>Results</p> <p>Every third CAP patient treated between 1975 and 1990 (every second man and every fifth woman) had entered the Register of Persons Convicted of Offences during the observation period, which is a significantly higher rate than the general population.</p> <p>Conclusion</p> <p>Results were compared to published results for CAP patients who were treated between 1953 and 1955 and followed over 20 years. Compared to the group of CAP patients from the 1950s, the results indicate that the risk for boys to enter the register for criminality has doubled and for girls, the risk seems to have increased sevenfold. The reasons for this change are discussed. Although hypothetical and perhaps speculative this higher risk of later criminality may be the result of lack of social control due to (1) rising consumption of alcohol, (2) changes in organisation of child social welfare work, (3) the school system, and (4) CAP methods that were implemented since 1970.</p

    Early Adoption of an Improved Household Energy System in Urban Rwanda

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    Cooking with solid fuels and inefficient cookstoves has adverse consequences for health, environment, and human well-being. Despite the promise of improved cookstoves to reduce these impacts, adoption rates are relatively low. Using a 2-wave sample of 144 households from the baseline and first midline of an ongoing 4-year randomized controlled trial in Rwanda, we analyze the drivers and associations of early adoption of a household energy intervention marketed by a private sector firm. Households sign an annual contract to purchase sustainably produced biomass pellets and lease a fan micro-gasification cookstove with verified emissions reductions in laboratory settings. Using difference-in-differences and fixed effects estimation techniques, we examine the association between take-up of the improved cooking system and household fuel expenditures, health outcomes, and time use for primary cooks. Thirty percent of households adopted the pellet and improved cookstove system. Adopting households had more assets, lower per capita total expenditures and cooking fuel expenditures, and higher per capita hygiene expenditures. Households with married household heads and female cooks were significantly more likely to adopt. Adjusting for confounders, we find significant reduction in primary cooks’ systolic blood pressure, self-reported prevalence of shortness of breath, an indicator of respiratory illness, time spent cooking, and household expenditures on charcoal. Our findings have implications for marketing of future clean fuel and improved cookstove programs in urban settings or where stoves and fuel are purchased. Analysis of follow-up surveys will allow for estimation of long-term impacts of adoption of interventions involving pellets and fan micro-gasification cookstoves

    Endoscopists attitudes on the publication of "quality" data for endoscopic procedures: a cross-sectional survey

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    <p>Abstract</p> <p>Background</p> <p>Whilst the public now have access to mortality & morbidity data for cardiothoracic surgeons, such "quality" data for endoscopy are not generally available. We studied endoscopists' attitudes to and the practicality of this data being published.</p> <p>Methods</p> <p>We sent a questionnaire to all consultant gastrointestinal (GI) surgeons, physicians and medical GI specialist registrars in the Northern region who currently perform GI endoscopic procedures (n = 132). We recorded endoscopist demographics, experience and current data collection practice. We also assessed the acceptability and utility of nine items describing endoscopic "quality" (e.g. mortality, complication & completion rates).</p> <p>Results</p> <p>103 (78%) doctors responded of whom 79 were consultants (77%). 61 (59%) respondents were physicians. 77 (75%) collect any "quality" data. The most frequently collected item was colonoscopic completion rate. Data were most commonly collected for appraisal, audit or clinical governance. The majority of doctors (54%) kept these data only available to themselves, and just one allowed the public to access this. The most acceptable data item was annual number of endoscopies and the least was crude upper GI bleeding mortality. Surgeons rated information less acceptable and less useful than physicians. Acceptability and utility scores were not related to gender, length of experience or current activity levels. Only two respondents thought all items totally unacceptable and useless.</p> <p>Conclusion</p> <p>The majority of endoscopists currently collect "quality" data for their practice although these are not widely available. The endoscopists in this study consider the publication of their outcome data to be "fairly unacceptable/not very useful" to "neutral" (score 2–3). If these data were made available to patients, consideration must be given to both its value and its acceptability.</p

    Expression and trans-specific polymorphism of self-incompatibility RNases in Coffea (Rubiaceae)

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    Self-incompatibility (SI) is widespread in the angiosperms, but identifying the biochemical components of SI mechanisms has proven to be difficult in most lineages. Coffea (coffee; Rubiaceae) is a genus of old-world tropical understory trees in which the vast majority of diploid species utilize a mechanism of gametophytic self-incompatibility (GSI). The S-RNase GSI system was one of the first SI mechanisms to be biochemically characterized, and likely represents the ancestral Eudicot condition as evidenced by its functional characterization in both asterid (Solanaceae, Plantaginaceae) and rosid (Rosaceae) lineages. The S-RNase GSI mechanism employs the activity of class III RNase T2 proteins to terminate the growth of "self" pollen tubes. Here, we investigate the mechanism of Coffea GSI and specifically examine the potential for homology to S-RNase GSI by sequencing class III RNase T2 genes in populations of 14 African and Madagascan Coffea species and the closely related self-compatible species Psilanthus ebracteolatus. Phylogenetic analyses of these sequences aligned to a diverse sample of plant RNase T2 genes show that the Coffea genome contains at least three class III RNase T2 genes. Patterns of tissue-specific gene expression identify one of these RNase T2 genes as the putative Coffea S-RNase gene. We show that populations of SI Coffea are remarkably polymorphic for putative S-RNase alleles, and exhibit a persistent pattern of trans-specific polymorphism characteristic of all S-RNase genes previously isolated from GSI Eudicot lineages. We thus conclude that Coffea GSI is most likely homologous to the classic Eudicot S-RNase system, which was retained since the divergence of the Rubiaceae lineage from an ancient SI Eudicot ancestor, nearly 90 million years ago.United States National Science Foundation [0849186]; Society of Systematic Biologists; American Society of Plant Taxonomists; Duke University Graduate Schoolinfo:eu-repo/semantics/publishedVersio

    TIGER : The gene expression regulatory variation landscape of human pancreatic islets

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    Genome-wide association studies (GWASs) identified hundreds of signals associated with type 2 diabetes (T2D). To gain insight into their underlying molecular mechanisms, we have created the translational human pancreatic islet genotype tissue-expression resource (TIGER), aggregating >500 human islet genomic datasets from five cohorts in the Horizon 2020 consortium T2DSystems. We impute genotypes using four reference panels and meta-analyze cohorts to improve the coverage of expression quantitative trait loci (eQTL) and develop a method to combine allele-specific expression across samples (cASE). We identify >1 million islet eQTLs, 53 of which colocalize with T2D signals. Among them, a low-frequency allele that reduces T2D risk by half increases CCND2 expression. We identify eight cASE colocalizations, among which we found a T2D-associated SLC30A8 variant. We make all data available through the TIGER portal (http://tiger.bsc.es), which represents a comprehensive human islet genomic data resource to elucidate how genetic variation affects islet function and translates into therapeutic insight and precision medicine for T2D.Peer reviewe

    Measurement of inclusive D*+- and associated dijet cross sections in photoproduction at HERA

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    Inclusive photoproduction of D*+- mesons has been measured for photon-proton centre-of-mass energies in the range 130 < W < 280 GeV and a photon virtuality Q^2 < 1 GeV^2. The data sample used corresponds to an integrated luminosity of 37 pb^-1. Total and differential cross sections as functions of the D* transverse momentum and pseudorapidity are presented in restricted kinematical regions and the data are compared with next-to-leading order (NLO) perturbative QCD calculations using the "massive charm" and "massless charm" schemes. The measured cross sections are generally above the NLO calculations, in particular in the forward (proton) direction. The large data sample also allows the study of dijet production associated with charm. A significant resolved as well as a direct photon component contribute to the cross section. Leading order QCD Monte Carlo calculations indicate that the resolved contribution arises from a significant charm component in the photon. A massive charm NLO parton level calculation yields lower cross sections compared to the measured results in a kinematic region where the resolved photon contribution is significant.Comment: 32 pages including 6 figure
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