89 research outputs found

    System among the corticosteroids: specificity and molecular dynamics.

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    Fil: Brookes, Jennifer C.. University College London; Estados UnidosFil: Galigniana, Mario Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Harker, Anthony H.. University College London; Estados UnidosFil: Stoneham, A. Marshall. University College London; Estados UnidosFil: Vinson, Gavin P.. Queen Mary University of London; Reino Unid

    The Global Lake Ecological Observatory Network (GLEON): the evolution of grassroots network science

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    Nine years later, with over 380 members from 40 countries, and 50 publications to its credit, GLEON is growing at a rapid pace and pushing the boundaries of the practice of network science. GLEON is really three networks: a network of lakes, data, and peopl

    Could humans recognize odor by phonon assisted tunneling?

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    Our sense of smell relies on sensitive, selective atomic-scale processes that are initiated when a scent molecule meets specific receptors in the nose. However, the physical mechanisms of detection are not clear. While odorant shape and size are important, experiment indicates these are insufficient. One novel proposal suggests inelastic electron tunneling from a donor to an acceptor mediated by the odorant actuates a receptor, and provides critical discrimination. We test the physical viability of this mechanism using a simple but general model. Using values of key parameters in line with those for other biomolecular systems, we find the proposed mechanism is consistent both with the underlying physics and with observed features of smell, provided the receptor has certain general properties. This mechanism suggests a distinct paradigm for selective molecular interactions at receptors (the swipe card model): recognition and actuation involve size and shape, but also exploit other processes.Comment: 10 pages, 1 figur

    Research methods for subgrouping low back pain

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    <p>Abstract</p> <p>Background</p> <p>There is considerable clinician and researcher interest in whether the outcomes for patients with low back pain, and the efficiency of the health systems that treat them, can be improved by 'subgrouping research'. Subgrouping research seeks to identify subgroups of people who have clinically important distinctions in their treatment needs or prognoses. Due to a proliferation of research methods and variability in how subgrouping results are interpreted, it is timely to open discussion regarding a conceptual framework for the research designs and statistical methods available for subgrouping studies (a method framework). The aims of this debate article are: (1) to present a method framework to inform the design and evaluation of subgrouping research in low back pain, (2) to describe method options when investigating prognostic effects or subgroup treatment effects, and (3) to discuss the strengths and limitations of research methods suitable for the hypothesis-setting phase of subgroup studies.</p> <p>Discussion</p> <p>The proposed method framework proposes six phases for studies of subgroups: studies of assessment methods, hypothesis-setting studies, hypothesis-testing studies, narrow validation studies, broad validation studies, and impact analysis studies. This framework extends and relabels a classification system previously proposed by McGinn et al (2000) as suitable for studies of clinical prediction rules. This extended classification, and its descriptive terms, explicitly anchor research findings to the type of evidence each provides. The inclusive nature of the framework invites appropriate consideration of the results of diverse research designs. Method pathways are described for studies designed to test and quantify prognostic effects or subgroup treatment effects, and examples are discussed. The proposed method framework is presented as a roadmap for conversation amongst researchers and clinicians who plan, stage and perform subgrouping research.</p> <p>Summary</p> <p>This article proposes a research method framework for studies of subgroups in low back pain. Research designs and statistical methods appropriate for sequential phases in this research are discussed, with an emphasis on those suitable for hypothesis-setting studies of subgroups of people seeking care.</p

    Development and worldwide use of non-lethal, and minimal population-level impact, protocols for the isolation of amphibian chytrid fungi

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    T.W.J.G., M.C.F., D.S.S., A.L., E.C., F.C.C., J.B., A.A.C., C.M., F.S., B.R.S., S.O., were supported through the Biodiversa project RACE: Risk Assessment of Chytridiomycosis to European Amphibian Biodiversity (NERC standard grant NE/K014455/1 and NE/E006701/1; ANR-08-BDVA-002-03). M.C.F., J.S., C.W., P.G. were supported by the Leverhulme Trust (RPG-2014-273), M.C.F., A.C., C.W. were supported by the Morris Animal Foundation. J.V. was supported by the Bolyai János Research Grant of the Hunagrian Academy of Sciences (BO/00597/14). F.G. and D.G. were supported by the Conservation Leadership Programme Future Conservationist Award. C.S.A. was supported by Fondecyt (No. 1181758). M.C.F. and A.C. were supported by. Mohamed bin Zayed Species Conservation Fund Project (152510704). GMR held a doctoral scholarship (SFRH/BD/69194/2010) from Fundação para a Ciência e a Tecnologia. L.F.T., C.L., L.P.R. K.R.Z., T.Y.J., T.S.J. were supported by São Paulo Research Foundation (FAPESP #2016/25358-3), the National Counsel of Technological and Scientific Development (CNPq #300896/2016–6) and a Catalyzing New International Collaborations grant from the United States NSF (OISE-1159513). C.S.A. was supported by Fondecyt (No. 1181758). T.M.D. was supported by the Royal Geographical Society and the Royal Zoological Society of Scotland. B.W. was supported by the National Research Foundation of Korea (2015R1D1A1A01057282).Peer reviewedPublisher PD

    Development and worldwide use of non-lethal, and minimal population-level impact, protocols for the isolation of amphibian chytrid fungi

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    © The Author(s) 2018.Parasitic chytrid fungi have emerged as a significant threat to amphibian species worldwide, necessitating the development of techniques to isolate these pathogens into culture for research purposes. However, early methods of isolating chytrids from their hosts relied on killing amphibians. We modified a pre-existing protocol for isolating chytrids from infected animals to use toe clips and biopsies from toe webbing rather than euthanizing hosts, and distributed the protocol to researchers as part of the BiodivERsA project RACE; here called the RML protocol. In tandem, we developed a lethal procedure for isolating chytrids from tadpole mouthparts. Reviewing a database of use a decade after their inception, we find that these methods have been applied across 5 continents, 23 countries and in 62 amphibian species. Isolation of chytrids by the non-lethal RML protocol occured in 18% of attempts with 207 fungal isolates and three species of chytrid being recovered. Isolation of chytrids from tadpoles occured in 43% of attempts with 334 fungal isolates of one species (Batrachochytrium dendrobatidis) being recovered. Together, these methods have resulted in a significant reduction and refinement of our use of threatened amphibian species and have improved our ability to work with this group of emerging pathogens.T.W.J.G., M.C.F., D.S.S., A.L., E.C., F.C.C., J.B., A.A.C., C.M., F.S., B.R.S., S.O., were supported through the Biodiversa project RACE: Risk Assessment of Chytridiomycosis to European Amphibian Biodiversity (NERC standard grant NE/K014455/1 and NE/E006701/1; ANR-08-BDVA-002-03). M.C.F., J.S., C.W., P.G. were supported by the Leverhulme Trust (RPG-2014-273), M.C.F., A.C., C.W. were supported by the Morris Animal Foundation. J.V. was supported by the Bolyai János Research Grant of the Hunagrian Academy of Sciences (BO/00597/14). F.G. and D.G. were supported by the Conservation Leadership Programme Future Conservationist Award. C.S.A. was supported by Fondecyt (No. 1181758). M.C.F. and A.C. were supported by. Mohamed bin Zayed Species Conservation Fund Project (152510704). GMR held a doctoral scholarship (SFRH/ BD/69194/2010) from Fundação para a Ciência e a Tecnologia. L.F.T., C.L., L.P.R. K.R.Z., T.Y.J., T.S.J. were supported by São Paulo Research Foundation (FAPESP #2016/25358-3), the National Counsel of Technological and Scientifc Development (CNPq #300896/2016–6) and a Catalyzing New International Collaborations grant from the United States NSF (OISE-1159513). C.S.A. was supported by Fondecyt (No. 1181758). T.M.D. was supported by the Royal Geographical Society and the Royal Zoological Society of Scotland. B.W. was supported by the National Research Foundation of Korea (2015R1D1A1A01057282).Peer Reviewe

    A genetic link between risk for Alzheimer's disease and severe COVID-19 outcomes via the OAS1 gene

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    Recently, we reported oligoadenylate synthetase 1 (OAS1) contributed to the risk of Alzheimer’s disease, by its enrichment in transcriptional networks expressed by microglia. However, the function of OAS1 within microglia was not known. Using genotyping from 1313 individuals with sporadic Alzheimer’s disease and 1234 control individuals, we confirm the OAS1 variant, rs1131454, is associated with increased risk for Alzheimer’s disease. The same OAS1 locus has been recently associated with severe coronavirus disease 2019 (COVID-19) outcomes, linking risk for both diseases. The single nucleotide polymorphisms rs1131454(A) and rs4766676(T) are associated with Alzheimer’s disease, and rs10735079(A) and rs6489867(T) are associated with severe COVID-19, where the risk alleles are linked with decreased OAS1 expression. Analysing single-cell RNA-sequencing data of myeloid cells from Alzheimer’s disease and COVID-19 patients, we identify co-expression networks containing interferon (IFN)-responsive genes, including OAS1, which are significantly upregulated with age and both diseases. In human induced pluripotent stem cell-derived microglia with lowered OAS1 expression, we show exaggerated production of TNF-α with IFN-γ stimulation, indicating OAS1 is required to limit the pro-inflammatory response of myeloid cells. Collectively, our data support a link between genetic risk for Alzheimer’s disease and susceptibility to critical illness with COVID-19 centred on OAS1, a finding with potential implications for future treatments of Alzheimer’s disease and COVID-19, and development of biomarkers to track disease progression

    Henipavirus Neutralising Antibodies in an Isolated Island Population of African Fruit Bats

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    Isolated islands provide valuable opportunities to study the persistence of viruses in wildlife populations, including population size thresholds such as the critical community size. The straw-coloured fruit bat, Eidolon helvum, has been identified as a reservoir for henipaviruses (serological evidence) and Lagos bat virus (LBV; virus isolation and serological evidence) in continental Africa. Here, we sampled from a remote population of E. helvum annobonensis fruit bats on Annobón island in the Gulf of Guinea to investigate whether antibodies to these viruses also exist in this isolated subspecies. Henipavirus serological analyses (Luminex multiplexed binding and inhibition assays, virus neutralisation tests and western blots) and lyssavirus serological analyses (LBV: modified Fluorescent Antibody Virus Neutralisation test, LBV and Mokola virus: lentivirus pseudovirus neutralisation assay) were undertaken on 73 and 70 samples respectively. Given the isolation of fruit bats on Annobón and their lack of connectivity with other populations, it was expected that the population size on the island would be too small to allow persistence of viruses that are thought to cause acute and immunising infections. However, the presence of antibodies against henipaviruses was detected using the Luminex binding assay and confirmed using alternative assays. Neutralising antibodies to LBV were detected in one bat using both assays. We demonstrate clear evidence for exposure of multiple individuals to henipaviruses in this remote population of E. helvum annobonensis fruit bats on Annobón island. The situation is less clear for LBV. Seroprevalences to henipaviruses and LBV in Annobón are notably different to those in E. helvum in continental locations studied using the same sampling techniques and assays. Whilst cross-sectional serological studies in wildlife populations cannot provide details on viral dynamics within populations, valuable information on the presence or absence of viruses may be obtained and utilised for informing future studies

    Recent Asian origin of chytrid fungi causing global amphibian declines

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    Globalized infectious diseases are causing species declines worldwide, but their source often remains elusive. We used whole-genome sequencing to solve the spatiotemporal origins of the most devastating panzootic to date, caused by the fungus Batrachochytrium dendrobatidis, a proximate driver of global amphibian declines. We traced the source of B. dendrobatidis to the Korean peninsula, where one lineage, BdASIA-1, exhibits the genetic hallmarks of an ancestral population that seeded the panzootic. We date the emergence of this pathogen to the early 20th century, coinciding with the global expansion of commercial trade in amphibians, and we show that intercontinental transmission is ongoing. Our findings point to East Asia as a geographic hotspot for B. dendrobatidis biodiversity and the original source of these lineages that now parasitize amphibians worldwide
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