59 research outputs found

    Anti-Endothelial Cell Antibodies are not frequently elevated in hospitalized patients with COVID-19

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    COVID-19 is now established to be associated with a thrombotic phenomenon, now called COVID-19 associated coagulopathy (CAC). Anti-Endothelial Cell Antibodies (AECA) are a heterogenous group of autoantibodies targeting various endothelial cell antigens or antigens adhering to endothelial cells, They are commonly observed in a variety of auto-immune and rheumatologic conditions, and were observed in patients with the severe acute respiratory syndrome (SARS) in 2005. We aimed to assess AECA status in patients with COVID-19 and their potential contributing role to endothelial injury and CAC. AECA identification was a relatively infrequent finding in COVID-19 patients on admission, and their presence, albeit in only 2/33 patients, was not associated with disease severity. However, as the autoantibodies were only measured at admission, we cannot exclude the possibility of pathogenic AECA developing later in the course of diseaseFurther studies using additional methods are needed to evaluate the presence and potential pathogenic role of AECA in later stages of COVID-19

    A Unified Nanopublication Model for Effective and User-Friendly Access to the Elements of Scientific Publishing

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    Scientific publishing is the means by which we communicate and share scientific knowledge, but this process currently often lacks transparency and machine-interpretable representations. Scientific articles are published in long coarse-grained text with complicated structures, and they are optimized for human readers and not for automated means of organization and access. Peer reviewing is the main method of quality assessment, but these peer reviews are nowadays rarely published and their own complicated structure and linking to the respective articles is not accessible. In order to address these problems and to better align scientific publishing with the principles of the Web and Linked Data, we propose here an approach to use nanopublications as a unifying model to represent in a semantic way the elements of publications, their assessments, as well as the involved processes, actors, and provenance in general. To evaluate our approach, we present a dataset of 627 nanopublications representing an interlinked network of the elements of articles (such as individual paragraphs) and their reviews (such as individual review comments). Focusing on the specific scenario of editors performing a meta-review, we introduce seven competency questions and show how they can be executed as SPARQL queries. We then present a prototype of a user interface for that scenario that shows different views on the set of review comments provided for a given manuscript, and we show in a user study that editors find the interface useful to answer their competency questions. In summary, we demonstrate that a unified and semantic publication model based on nanopublications can make scientific communication more effective and user-friendly

    Subnormal vitamin B12 concentrations and anaemia in older people: a systematic review

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    <p>Abstract</p> <p>Background</p> <p>Pernicious anaemia is undeniably associated with vitamin B12 deficiency, but the association between subnormal vitamin B12 concentrations and anaemia in older people is unclear. The aim of this systematic review was to evaluate the association between subnormal vitamin B12 concentrations and anaemia in older people.</p> <p>Methods</p> <p>Clinical queries for aetiology and treatment in bibliographic databases (PubMed [01/1949-10/2009]; EMBASE [01/1980-10/2009]) were used. Reference lists were checked for additional relevant studies. Observational studies (≥50 participants) and randomized placebo-controlled intervention trials (RCTs) were considered.</p> <p>Results</p> <p>25 studies met the inclusion criteria. Twenty-one observational cross-sectional studies (total number of participants n = 16185) showed inconsistent results. In one longitudinal observational study, low vitamin B12 concentrations were not associated with an increased risk of anaemia (total n = 423). The 3 RCTs (total n = 210) were well-designed and showed no effect of vitamin B12 supplementation on haemoglobin concentrations during follow-up in subjects with subnormal vitamin B12 concentrations at the start of the study. Due to large clinical and methodological heterogeneity, statistical pooling of data was not performed.</p> <p>Conclusions</p> <p>Evidence of a positive association between a subnormal serum vitamin B12 concentration and anaemia in older people is limited and inconclusive. Further well-designed studies are needed to determine whether subnormal vitamin B12 is a risk factor for anaemia in older people.</p

    The relationship between subtypes of depression and cardiovascular disease: a systematic review of biological models

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    A compelling association has been observed between cardiovascular disease (CVD) and depression, suggesting individuals with depression to be at significantly higher risk for CVD and CVD-related mortality. Systemic immune activation, hypothalamic–pituitary–adrenal (HPA) axis hyperactivity, arterial stiffness and endothelial dysfunction have been frequently implicated in this relationship. Although a differential epidemiological association between CVD and depression subtypes is evident, it has not been determined if this indicates subtype specific biological mechanisms. A comprehensive systematic literature search was conducted using PubMed and PsycINFO databases yielding 147 articles for this review. A complex pattern of systemic immune activation, endothelial dysfunction and HPA axis hyperactivity is suggestive of the biological relationship between CVD and depression subtypes. The findings of this review suggest that diagnostic subtypes rather than a unifying model of depression should be considered when investigating the bidirectional biological relationship between CVD and depression. The suggested model of a subtype-specific biological relationship between depression and CVDs has implications for future research and possibly for diagnostic and therapeutic processes

    Are anti-SARS-CoV-2 S/N IgG/IgM antibodies always predictive of previous SARS-CoV-2 infection?

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    Objectives: We planned this study to verify whether immunoassays for quantifying anti-SARS-CoV-2 IgG/IgM antibodies against both spike (S) and nucleocapsid (N) proteins may be used for identifying previous SARS-CoV-2 infections.Methods: The study population consisted of a cohort of fully vaccinated healthcare workers. All study subjects underwent regular medical visits and molecular testing for diagnosing SARS-CoV-2 infections every 2-4 weeks between 2020-2022. Venous blood was drawn for measuring anti-SARS-CoV-2 antibodies with MAGLUMI 2019-nCoV lgG/ IgM CLIA Assays directed against both SARS-CoV-2 S and N proteins.Results: Overall, 31/53 (58.5%) subjects had tested positive for SARS-CoV-2 by RT-PCR throughout the study (24 once, 7 twice). No positive correlation was found between antiSARS-CoV-2 S/N IgM antibodies and molecular test positivity. In univariate regression analysis, both a molecular test positivity (r=0.33; p=0.015) and the number of positive molecular tests (r=0.43; p=0.001), but not vaccine doses (r=-0.12; p=0.392), were significantly correlated with anti-SARS-CoV-2 S/N IgG antibodies. These two associations remained significant in multiple linear regression analysis (p=0.029 and p&lt;0.001, respectively) after adjusting for sex, age, body mass index, and vaccine doses. In ROC curve analysis, anti-SARS-CoV-2 S/N IgG antibodies significantly predicted molecular test positivity (AUC, 0.69; 95% CI; 0.55-0.84), with the best cutoff of 0.05 AU/mL displaying 67.9% accuracy, 0.97 sensitivity, and 0.27 specificity.Conclusions: Although anti-SARS-CoV-2 S/N IgG antibodies provide helpful information for identifying previous SARS-CoV-2 infections, a lower cutoff than that of sample reactivity should be used. Anti-SARS-CoV-2 S/N IgM antibodies using conventional cutoffs seem useless for this purpose

    The pronounced decline of anti-SARS-CoV-2 spike trimeric IgG and RBD IgG in baseline seronegative individuals six months after BNT162b2 vaccination is consistent with the need for vaccine boosters

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    Background: This observational retrospective study aimed to define the kinetics of serum levels of anti-SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) spike trimeric and anti-receptor binding domain (RBD) IgG antibodies up to 6 months after BNT162b2 vaccination. Methods: The sample consisted of 86 SARS-CoV-2 baseline seronegative subjects (median age 45 years, IQR 31-53 years; 52.3% females) undergoing vaccination with Pfizer/BioNTech BNT162b2. Blood was drawn before receiving the first and the second vaccine dose, as well as 1, 3 and 6 months after the second vaccine dose. The serum levels of anti-SARS-CoV-2 spike trimeric IgG and RBD IgG antibodies were assayed. Results: The peak of both antibodies types was reached 1 month after the second dose (2808 and 2163 BAU/mL for anti-SARS-CoV-2 spike trimeric IgG and RBD IgG), after which serum levels progressively declined, falling after 6 months to 486 BAU/mL and 167 BAU/mL for anti-SARS-CoV-2 spike trimeric IgG and RBD IgG, respectively. The median rate of 6-month decline was 85% and 93% for anti-SARS-CoV-2 spike trimeric IgG and RBD IgG, respectively. The rate of vaccine recipients with serum antibodies levels above the 80% threshold of vaccine efficacy declined from over 95% at the peak to 72% and 5% at 6 months for anti-SARS-CoV-2 spike trimeric IgG and RBD IgG, respectively. Conclusions: The results of this retrospective observational study are consistent with the need for timely administration of vaccine boosters to prevent that humoral immunity will wane
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