230 research outputs found

    Large-Scale Analysis of the Accuracy of the Journal Classification Systems of Web of Science and Scopus

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    Journal classification systems play an important role in bibliometric analyses. The two most important bibliographic databases, Web of Science and Scopus, each provide a journal classification system. However, no study has systematically investigated the accuracy of these classification systems. To examine and compare the accuracy of journal classification systems, we define two criteria on the basis of direct citation relations between journals and categories. We use Criterion I to select journals that have weak connections with their assigned categories, and we use Criterion II to identify journals that are not assigned to categories with which they have strong connections. If a journal satisfies either of the two criteria, we conclude that its assignment to categories may be questionable. Accordingly, we identify all journals with questionable classifications in Web of Science and Scopus. Furthermore, we perform a more in-depth analysis for the field of Library and Information Science to assess whether our proposed criteria are appropriate and whether they yield meaningful results. It turns out that according to our citation-based criteria Web of Science performs significantly better than Scopus in terms of the accuracy of its journal classification system

    Lipids and Cardiovascular Organ Damage in Type 2 Diabetes Mellitus

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    One of the mechanisms underlying increased cardiovascular (CV) risk in patients with type 2 diabetes mellitus is atherogenic dyslipidemia, that is characterized by elevated triglycerides and free fatty acids (FFAs) levels, low levels of high-density lipoprotein cholesterol (HDL) and an excess of small dense low-density lipoprotein particles (sdLDLs). Each component of atherogenic dyslipidemia is associated with CV events and triggers alterations at different levels of CV system through different pathways. FFAs and sdLDLs induce endothelial dysfunction, intima-media thickening, plaque formation and arterial stiffening through increase in oxidative stress and inflammation and promoting lipid accumulation and smooth muscle cells (SMCs) proliferation in vascular wall. In contrast, HDL exerts protective effect on arterial wall by increasing nitric oxide availability, by reverse cholesterol transport and by suppression of SMCs proliferation and migration. FFAs overload results in a switch in myocardial substrate utilization, causing changes in myocardial energy metabolism and an increase in baseline oxygen consumption. Accumulation of toxic lipid intermediates in myocardium provokes damage of cellular membrane integrity, organelle dysfunction and apoptosis with consequent decrease in myocardial performance. The structural and functional changes in myocardium can be reversed by therapy with reconstructed HDL. Therefore, the impact of atherogenic dyslipidemia on CV system is not limited on accelerated atherosclerosis, but causes different organ damages that must be considered in their complexity

    Serum Neurofilament Light is elevated in COVID-19 Positive Adults in the ICU and is associated with Co-Morbid Cardiovascular Disease, Neurological Complications, and Acuity of Illness

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    In critically ill COVID-19 patients, the risk of long-term neurological consequences is just beginning to be appreciated. While recent studies have identified that there is an increase in structural injury to the nervous system in critically ill COVID-19 patients, there is little known about the relationship of COVID-19 neurological damage to the systemic inflammatory diseases also observed in COVID-19 patients. The purpose of this pilot observational study was to examine the relationships between serum neurofilament light protein (NfL, a measure of neuronal injury) and co-morbid cardiovascular disease (CVD) and neurological complications in COVID-19 positive patients admitted to the intensive care unit (ICU). In this observational study of one-hundred patients who were admitted to the ICU in Tucson, Arizona between April and August 2020, 89 were positive for COVID-19 (COVID-pos) and 11 was COVID-negative (COVID-neg). A healthy control group (n=8) was examined for comparison. The primary outcomes and measures were subject demographics, serum NfL, presence and extent of CVD, diabetes, sequential organ failure assessment score (SOFA), presence of neurological complications, and blood chemistry panel data. COVID-pos patients in the ICU had significantly higher mean levels of Nfl (229.6 ± 163 pg/ml) compared to COVID-neg ICU patients (19.3 ± 5.6 pg/ml), Welch's t-test, p =.01 and healthy controls (12.3 ± 3.1 pg/ml), Welch's t-test p =.005. Levels of Nfl in COVID-pos ICU patients were significantly higher in patients with concomitant CVD and diabetes (n=35, log Nfl 1.6±.09), and correlated with higher SOFA scores (r=.5, p =.001). These findings suggest that in severe COVID-19 disease, the central neuronal and axonal damage in these patients may be driven, in part, by the level of systemic cardiovascular disease and peripheral inflammation. Understanding the contributions of systemic inflammatory disease to central neurological degeneration in these COVID-19 survivors will be important to the design of interventional therapies to prevent long-term neurological and cognitive dysfunction

    Evaluation of a Novel Method Using Computed Tomography to Predict New Onset of Atrial Fibrillation or Embolic Events after Transcatheter Aortic Valve Implantation: the Role of Hounsfield Unit Density Ratio in the Left Atrial Appendage

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    Backgrounds: Evaluation of left atrial appendage (LAA) with angio-computed tomography (CCTA) in order to predict new onset of atrial fibrillation (AF) or embolic events is a new upcoming topic. No previous reported studies are available in patients undergoing transcatheter aortic valve implantation (TAVI). Methods: We analyzed pre-procedural CCTA scans of 325 patients who underwent TAVI performing a linear coefficient of attenuation analyses with Hounsfield units (HU) in LAA. HU in LAA distal and proximal was calculated, as well as the ratio. A sensibility and specificity analyses was conducted in order to identify the optimal cutoff to predict new onset AF or embolic events after TAVI. Results: Patients were divided into 4 groups according to the presence of AF. Baseline clinical and echocardiographic features were similar except for a significantly higher STS score and mitral regurgitation severity in PRE-TAVI AF group (p=0.003 and p=0.002 respectively). HU analyses showed a statistical difference in measure performed in LAA distal and in the HU LAA distal/Proximal ratio, with the lowest value in patients with pre-TAVI AF (p<0.001 and p<0.001 respectively). The ROC analyses found 0.84 as the cut-off for to predict the composite endpoint of new AF or embolic events, with sensitivity of 51% and specificity of 52% (p=0.008). Conclusion: In patients with aortic stenosis (AS), use of LAA assessment with CCTA to predict embolic events or new onset AF is no efficacy and cannot be substituted clinical indications for prevention and therapy of embolic events

    Análisis bibliométrico de la producción científica peruana en cardiología y medicina cardiovascular

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    Objective. To determine the characteristics and trend of the articles published on cardiology and cardiovascular medicine in the Peruvian context, and to understand how it has changed over the years. Materials and methods. A bibliometric study of original articles published up to 2020 by Peruvian authors in journals indexed under the category “Cardiac & Cardiovascular Systems” in Web of Science (WOS) was performed. The articles were included according to the selection criteria in the Rayyan web application and the bibliometric analysis was performed using the Bibliometrix package in the R programming language and VOSviewer. Results. A total of 159 published articles were included, and an increase in the number of publications since 2015 was observed. The most cited article was a clinical trial by Fitchett et al. and published in 2016. Miranda JJ was the Peruvian author with the highest number of published articles followed by Hernández AV and Málaga G. The institutional affiliation with the highest number of original articles was Universidad Peruana Cayetano Heredia. Regarding the terms or keywords, it was found that most of the published studies had terms related to epidemiology, while in the most recent articles, the terms were related to outcomes or specific interventions that are used in clinical studies. Conclusions. In the last five years, there has been an increase in the scientific production on cardiology and cardiovascular medicine by authors with Peruvian institutional affiliation, with a greater production from the Universidad Peruana Cayetano Heredia. The journal with the highest number of publications by authors with Peruvian institutional affiliation on cardiology and cardiovascular medicine was Circulation, where two of the most cited articles with Peruvian institutional affiliation were also found.Objetivo. Determinar las características y la tendencia de los artículos publicados sobre cardiología y medicina cardiovascular en el contexto peruano, y comprender cómo ha cambiado a lo largo de los años. Materiales y métodos. Se realizó un estudio bibliométrico de artículos originales publicados hasta el año 2020 por autores peruanos en revistas indexadas bajo la categoría «Cardiac & Cardiovascular Systems» en Web of Science (WOS). Se incluyeron los artículos según los criterios de selección en el aplicativo web Rayyan y se realizó el análisis bibliométrico mediante el paquete Bibliometrix en el lenguaje de programación R y VOSviewer. Resultados. Se incluyeron 159 artículos publicados, y se observó un incremento del número de publicaciones desde 2015. El artículo más citado fue un ensayo clínico realizado por Fitchett et al. y publicado en 2016. Miranda JJ fue el autor peruano con mayor número artículos publicados seguido de Hernández AV y Málaga G. La filiación institucional con mayor número de artículos originales fue la Universidad Peruana Cayetano Heredia. En cuanto a los términos o palabras clave, se encontró que la mayor cantidad de estudios publicados contaban con términos relacionados con la epidemiología, mientras que en los artículos más recientes, los términos se relacionaron con desenlaces o intervenciones específicas que son utilizados en estudios clínicos. Conclusiones. Se encontró un incremento en los últimos cinco años en la producción científica sobre cardiología y medicina cardiovascular de autores con filiación institucional peruana, con una mayor producción de la Universidad Peruana Cayetano Heredia. La revista con mayores publicaciones de autores con filiación institucional peruana sobre cardiología y medicina cardiovascular fue Circulation, donde también se encontraron dos de los artículos con filiación institucional peruana más citados

    Acute Limb Ischemia and Pseudoaneurysm of Femoralis Artery Post Cardiac Catheterization in Pediatric

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    Acute Limb Ischemia and Pseudoaneurysm of Femoralis Artery Post CardiacCatheterization in Pediatri

    The Research Space: using the career paths of scholars to predict the evolution of the research output of individuals, institutions, and nations

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    In recent years scholars have built maps of science by connecting the academic fields that cite each other, are cited together, or that cite a similar literature. But since scholars cannot always publish in the fields they cite, or that cite them, these science maps are only rough proxies for the potential of a scholar, organization, or country, to enter a new academic field. Here we use a large dataset of scholarly publications disambiguated at the individual level to create a map of science-or research space-where links connect pairs of fields based on the probability that an individual has published in both of them. We find that the research space is a significantly more accurate predictor of the fields that individuals and organizations will enter in the future than citation based science maps. At the country level, however, the research space and citations based science maps are equally accurate. These findings show that data on career trajectories-the set of fields that individuals have previously published in-provide more accurate predictors of future research output for more focalized units-such as individuals or organizations-than citation based science maps

    When a meta-analysis equals a single large-scale trial with meaningful follow-up

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    © 2021 The Author(s). Published on behalf of the European Society of Cardiology. All rights reserved. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1093/eurheartj/ehab460This commentary refers to ‘Cardiac mortality in patients randomised to elective coronary revascularisation plus medical therapy or medical therapy alone: a systematic review and meta-analysis’, by E.P. Navarese et al. doi:10.1093/ eurheartj/ehab246 and the discussion piece ‘In the pool: dilution or drowning?’, by V. Dayan et al. doi:10.1093/ eurheartj/ehab443Peer reviewe
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