1,720,973 research outputs found
Sympathetic nervous system activation and heart failure: Current state of evidence and the pathophysiology in the light of novel biomarkers
No full textHeart failure (HF) is a complex clinical syndrome characterized by the activation of at least several neurohumoral pathways that have a common role in maintaining cardiac output and adequate perfusion pressure of target organs and tissues. The sympathetic nervous system (SNS) is upregulated in HF as evident in dysfunctional baroreceptor and chemoreceptor reflexes, circulating and neuronal catecholamine spillover, attenuated parasympathetic response, and augmented sympathetic outflow to the heart, kidneys and skeletal muscles. When these sympathoexcitatory effects on the cardiovascular system are sustained chronically they initiate the vicious circle of HF progression and become associated with cardiomyocyte apoptosis, maladaptive ventricular and vascular remodeling, arrhythmogenesis, and poor prognosis in patients with HF. These detrimental effects of SNS activity on outcomes in HF warrant adequate diagnostic and treatment modalities. Therefore, this review summarizes basic physiological concepts about the interaction of SNS with the cardiovascular system and highlights key pathophysiological mechanisms of SNS derangement in HF. Finally, special emphasis in this review is placed on the integrative and up-to-date overview of diagnostic modalities such as SNS imaging methods and novel laboratory biomarkers that could aid in the assessment of the degree of SNS activation and provide reliable prognostic information among patients with HF
Clinical use of ivabradine in the acute coronary syndrome: A systematic review and narrative synthesis of current evidence
No full textHeart rate (HR) lowering during acute coronary syndrome (ACS) is beneficial as it reduces myocardial oxygen consumption. However, the role of ivabradine as an HR-lowering agent in the setting of ACS is not clear. We aimed to systematically review and synthesize the current evidence on the role of ivabradine use in the ACS. A systematic review was conducted for eligible randomized clinical trials and quasi-experimental studies, between 2009 and 2020, that investigated the use of ivabradine in ACS. Various clinical endpoints were evaluated such as major adverse cardiovascular events, efficacy in HR control, impact on left ventricular (LV) dimensions and function, and overall safety. Eleven publications were included encompassing a total of 1833 patients. The mean age of the examined cohort was 57 +/- 11 years and 80 % were men. Seven studies were in the setting of STsegment elevation myocardial infarction (MI) while the remaining studies also included patients with unstable angina and non-ST-segment elevation MI. Ivabradine was administered as a peroral drug with dosing from 2.5 to 7.5 mg b.i.d. Overall, the addition of ivabradine was superior to the control arm concerning HR control with a good safety profile. Beneficial effects on LV function and potential impact on infarct size reduction were observed as well. The use of ivabradine appeared to not affect short-term mortality. In conclusion, the use of ivabradine for HR control is safe, feasible, and efficacious for HR control in the ACS. Further studies are required to elucidate other potentially beneficial effects of ivabradine
Carbohydrate Antigen 125: A Biomarker at the Crossroads of Congestion and Inflammation in Heart Failure
Full text linkBecause heart failure (HF) is more lethal than some of the common malignancies in the general population, such as prostate cancer in men and breast cancer in women, there is a need for a cost-effective prognostic biomarker in HF beyond natriuretic peptides, especially concerning congestion, the most common reason for the hospitalisation of patients with worsening of HF. Furthermore, despite diuretics being the mainstay of treatment for volume overload in HF patients, no randomised trials have shown the mortality benefits of diuretics in HF patients, and appropriate diuretic titration strategies in this population are unclear. Recently, carbohydrate antigen (CA) 125, a well-established marker of ovarian cancer, emerged as both a prognostic indicator and a guide in tailoring decongestion therapy for patients with HF. Hence, in this review the authors present the molecular background regarding the role of CA125 in HF and address valuable clinical aspects regarding the relationship of CA125 with both prognosis and therapeutic management in HF
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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