471 research outputs found

    Viral etiology of hospitalized acute lower respiratory infections in children under 5 years of age – a systematic review and meta-analysis

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    Aim To estimate the proportional contribution of influenza viruses (IV), parainfluenza viruses (PIV), adenoviruses (AV), and coronaviruses (CV) to the burden of severe acute lower respiratory infections (ALRI). Methods The review of the literature followed PRISMA guidelines. We included studies of hospitalized children aged 0-4 years with confirmed ALRI published between 1995 and 2011. A total of 51 studies were included in the final review, comprising 56 091 hospitalized ALRI episodes. Results IV was detected in 3.0% (2.2%-4.0%) of all hospitalized ALRI cases, PIV in 2.7% (1.9%-3.7%), and AV in 5.8% (3.4%-9.1%). CV are technically difficult to culture, and they were detected in 4.8% of all hospitalized ALRI patients in one study. When respiratory syncytial virus (RSV) and less common viruses were included, at least one virus was detected in 50.4% (40.0%-60.7%) of all hospitalized severe ALRI episodes. Moreover, 21.9% (17.7%-26.4%) of these viral ALRI were mixed, including more than one viral pathogen. Among all severe ALRI with confirmed viral etiology, IV accounted for 7.0% (5.5%-8.7%), PIV for 5.8% (4.1%-7.7%), and AV for 8.8% (5.3%-13.0%). CV was found in 10.6% of virus-positive pneumonia patients in one study. Conclusions This article provides the most comprehensive analysis of the contribution of four viral causes to severe ALRI to date. Our results can be used in further cost-effectiveness analyses of vaccine development and implementation for a number of respiratory viruses

    The acanthamoeba shikimate pathway has a unique molecular arrangement and is essential for aromatic amino acid biosynthesis

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    The shikimate pathway is the only known biosynthetic route for de novo synthesis of aromatic compounds. It is described as an ancient eukaryotic innovation that has been retained in a subset of eukaryotes, replaced in plants through the acquisition of the chloroplast, but lost in many including humans. Herein, we demonstrate that Acanthamoeba castellanii possesses the shikimate pathway by biochemical and a combination of bioinformatics and molecular biological methods. The growth of A. castellanii (Neff strain and a recently isolated clinical specimen, both T4 genotypes) is inhibited by glyphosate [N-(phosphonomethyl) glycine], an inhibitor of EPSP synthase and the addition of phenylalanine and tryptophan, which are dependent on the shikimate pathway, rescued A. castellanii from glyphosate indicating that glyphosate was specific in action. A. castellanii has a novel complement of shikimate pathway enzymes including unique gene fusions, two Type I and one Type II DAHP synthases (for which their likely sensitivities to feedback inhibition by phenylalanine, tyrosine and tryptophan has been modelled) and a canonical chorismate synthase. The shikimate pathway in A. castellanii therefore has a novel molecular arrangement, is required for amino acid biosynthesis and represents an attractive target for antimicrobials

    A core outcome set for localised prostate cancer effectiveness trials : protocol for a systematic review of the literature and stakeholder involvement through interviews and a Delphi survey

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    Acknowledgements We would like to thank Professor Craig Ramsay, Professor Luke Vale, and Professor Vikki Entwistle for their comments on earlier drafts of the protocol. This study is funded by the Cancer Research Aberdeen and North East Scotland (CRANES) charity. Paula Williamson would like to acknowledge funding from the European Union Seventh Framework Programme (FP7/2007-2013, FP7/2007-2011) under grant agreement number 305081 for the COMET initiative, which provided support for this work.Peer reviewedPublisher PD

    The effectiveness and cost-effectiveness of resuscitative endovascular balloon occlusion of the aorta (REBOA) for trauma patients with uncontrolled torso haemorrhage : study protocol for a randomised clinical trial (the UK-REBOA trial)

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    Acknowledgements The UK-REBOA trial grantholders include Jan O. Jansen, University of Aberdeen, UK, and University of Alabama at Birmingham, USA; Marion K. Campbell, University of Aberdeen, UK; Chris Moran, Nottingham University Hospital Trust, UK; Karim Brohi, Queen Mary University of London, UK; Fiona Lecky, University of Sheffield, UK; Robbie Lendrum, Bart’s Health NHS Trust, UK; Graeme MacLennan, University of Aberdeen, UK; Jonathan J. Morrison, University of Maryland, USA; Nigel Tai, Academic Department of Military Surgery and Trauma, Royal Centre for Defence Medicine, UK; Tim Harris, Bart’s Health NHS Trust, UK; John Norrie, University of Edinburgh, UK; Dwayne Boyers, University of Aberdeen, UK; Alan Paterson, University of Strathclyde, UK; and Nick Welch. Funding {4} This study/project is funded by the National Institute for Health Research (NIHR) HTA Programme (reference 14/199/09). The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care. The funder has/had no role in the design of the study; the collection, analysis, and interpretation of data; or writing the manuscript. The Health Services Research Unit, Institute of Applied Health Sciences (University of Aberdeen), is core-funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorates.Peer reviewedPublisher PD

    Active sites for ice nucleation differ depending on nucleation mode

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    The nucleation of ice crystals in clouds is poorly understood, despite being of critical importance for our planet's climate. Nucleation occurs largely at rare "active sites" present on airborne particles such as mineral dust, but the nucleation pathway is distinct under different meteorological conditions. These give rise to two key nucleation pathways where a particle is either immersed in a supercooled liquid water droplet (immersion freezing mode) or suspended in a supersaturated vapor (deposition mode). However, it is unclear if the same active sites are responsible for nucleation in these two modes. Here, we directly compare the sites that are active in these two modes by performing immersion freezing and deposition experiments on the same thin sections of two atmospherically important minerals (feldspar and quartz). For both substrates, we confirm that nucleation is dominated by a limited number of sites and show that there is little correlation between the two sets of sites operating in each experimental method: across both materials, only six out of 73 sites active for immersion freezing nucleation were also active for deposition nucleation. Clearly, different properties determine the activity of nucleation sites for each mode, and we use the pore condensation and freezing concept to argue that effective deposition sites have size and/or geometry requirements not of relevance to effective immersion freezing sites. Hence, the ability to nucleate is pathway dependent, and the mode of nucleation has to be explicitly considered when applying experimental data in cloud models. [Abstract copyright: Copyright © 2021 the Author(s). Published by PNAS.

    Defective Gp130-Mediated Signal Transducer and Activator of Transcription (Stat) Signaling Results in Degenerative Joint Disease, Gastrointestinal Ulceration, and Failure of Uterine Implantation

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    The receptor subunit gp130 transduces multiple cell type–specific activities of the leukemia inhibitory factor (LIF)/interleukin (IL)-6 family of cytokines through the signal transducer and activator of transcription (STAT) and src homology 2 domain–bearing protein tyrosine phosphatase (SHP)-2/ras/Erk pathways. To define STAT-dependent physiological responses, we generated mice with a COOH-terminal gp130ΔSTAT “knock-in” mutation which deleted all STAT-binding sites. gp130ΔSTAT mice phenocopyed mice deficient for IL-6 (impaired humoral and mucosal immune and hepatic acute phase responses) and LIF (failure of blastocyst implantation). However, unlike mice with null mutations in any of the components in the gp130 signaling pathway, gp130ΔSTAT mice also displayed gastrointestinal ulceration and a severe joint disease with features of chronic synovitis, cartilaginous metaplasia, and degradation of the articular cartilage. Mitogenic hyperresponsiveness of synovial cells to the LIF/IL-6 family of cyto-kines was caused by sustained gp130-mediated SHP-2/ras/Erk activation due to impaired STAT-mediated induction of suppressor of cytokine signaling (SOCS) proteins which normally limits gp130 signaling. Therefore, the joint pathology in gp130ΔSTAT mice is likely to arise from the disturbance of the otherwise balanced activation of the SHP-2/ras/Erk and STAT signaling cascades emanating from gp130
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