56 research outputs found

    Risk factors for SARS-CoV-2 seroprevalence following the first pandemic wave in UK healthcare workers in a large NHS Foundation Trust [version 1; peer review: awaiting peer review]

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    Background: We aimed to measure SARS-CoV-2 seroprevalence in a cohort of healthcare workers (HCWs) during the first UK wave of the COVID-19 pandemic, explore risk factors associated with infection, and investigate the impact of antibody titres on assay sensitivity. Methods: HCWs at Sheffield Teaching Hospitals NHS Foundation Trust were prospectively enrolled and sampled at two time points. SARS-CoV-2 antibodies were tested using an in-house assay for IgG and IgA reactivity against Spike and Nucleoprotein (sensitivity 99·47%, specificity 99·56%). Data were analysed using three statistical models: a seroprevalence model, an antibody kinetics model, and a heterogeneous sensitivity model. Results: As of 12th June 2020, 24·4% (n=311/1275) of HCWs were seropositive. Of these, 39·2% (n=122/311) were asymptomatic. The highest adjusted seroprevalence was measured in HCWs on the Acute Medical Unit (41·1%, 95% CrI 30·0–52·9) and in Physiotherapists and Occupational Therapists (39·2%, 95% CrI 24·4–56·5). Older age groups showed overall higher median antibody titres. Further modelling suggests that, for a serological assay with an overall sensitivity of 80%, antibody titres may be markedly affected by differences in age, with sensitivity estimates of 89% in those over 60 years but 61% in those ≤30 years. Conclusions: HCWs in acute medical units working closely with COVID-19 patients were at highest risk of infection, though whether these are infections acquired from patients or other staff is unknown. Current serological assays may underestimate seroprevalence in younger age groups if validated using sera from older and/or more symptomatic individuals

    Countering Extremists on Social Media:Challenges for Strategic Communication and Content Moderation

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    Extremist exploitation of social media platforms is an important regulatory question for civil society, government, and the private sector. Extremists exploit social media for a range of reasons-from spreading hateful narratives and propaganda to financing, recruitment, and sharing operational information. Policy responses to this question fit under two headings, strategic communication and content moderation. At the center of both of these policy responses is a calculation about how best to limit audience exposure to extremist narratives and maintain the marginality of extremist views, while being conscious of rights to free expression and the appropriateness of restrictions on speech. This special issue on "Countering Extremists on Social Media: Challenges for Strategic Communication and Content Moderation" focuses on one form of strategic communication, countering violent extremism. In this editorial we discuss the background and effectiveness of this approach, and introduce five articles which develop multiple strands of research into responses and solutions to extremist exploitation of social media. We conclude by suggesting an agenda for future research on how multistakeholder initiatives to challenge extremist exploitation of social media are conceived, designed, and implemented, and the challenges these initiatives need to surmount

    Chemical Constituents from Gouania longipetala and Glyphaea brevis

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    Five compounds were isolated altogether from the two medicinal plants. Glycerol monovalerate (1), palmarumycin BG1 (2), and de-O-methyllasiodiplodin (3) were isolated from G. longipetala. Additionally, epicatechin (4) and its’ dimer procyanidin B2 (5) were isolated from the stem bark of G. brevis. Their structures were elucidated by spectroscopic experiments. 1 displayed moderate antibacterial activities with the least MIC of 125 µg/mL against E. faecalis. In addition, 1 reduced DPPH with an IC50 value of 102.34 µg/mL

    Neurofilament triplet proteins are restricted to a subset of neurons in the rat neocortex.

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    The cellular localisation of neurofilament triplet subunits was investigated in the rat neocortex. A subset of mainly pyramidal neurons showed colocalisation of subunit immunolabelling throughout the neocortex, including labelling with the antibody SMI32, which has been used extensively in other studies of the primate cortex as a selective cellular marker. Neurofilament-labelled neurons were principally localised to two or three cell layers in most cortical regions, but dramatically reduced labelling was present in areas such as the perirhinal cortex, anterior cingulate and a strip of cortex extending from caudal motor regions through the medial parietal region to secondary visual areas. However, quantitative analysis demonstrated a similar proportion (10-20%) of cells with neurofilament triplet labelling in regions of high or low labelling. Combining retrograde tracing with immunolabelling showed that cellular content of the neurofilament proteins was not correlated with the length of projection. Double labelling immunohistochemistry demonstrated that neurofilament content in axons was closely associated with myelination. Analysis of SMI32 labelling in development indicated that content of this epitope within cell bodies was associated with relatively late maturation, between postnatal days 14 and 21. This study is further evidence of a cell type-specific regulation of neurofilament proteins within neocortical neurons. Neurofilament triplet content may be more closely related to the degree of myelination, rather than the absolute length, of the projecting axon

    Chemical constituents from <i>Gouania longipetala</i> and <i>Glyphaea brevis</i>

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    <div><p>Five compounds were isolated altogether from the two medicinal plants. Glycerol monotricosanoate (<b>1</b>), palmarumycin BG1 (<b>2</b>) and de-<i>O</i>-methyllasiodiplodin (<b>3</b>) were isolated from <i>Gouania longipetala</i>. In addition, epicatechin (<b>4</b>) and its dimer procyanidin B2 (<b>5</b>) were isolated from the stem bark of <i>Glyphaea brevis</i>. Their structures were elucidated by using spectroscopic experiments. They exhibited radical scavenging and moderate antibacterial effects.</p></div
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