1,721,059 research outputs found
Cardioprotective Role of Sphingosine 1-Phosphate Receptor Agonist Fingolimod (FTY720) in Global Ischemia-Reperfusion Models
Get PDFBackground and purpose: Ischemic Heart Diseases (IHD) are the most common cause of morbidity and mortality. Incidence and prevalence is continuously growing. There is an escalating risk for revascularization or resuscitation in patients with IHD. Recently, it has been reported that sphingosine 1-phosphate receptor agonist plays anti-apoptotic and anti-inflammatory role in ischemia-reperfusion injury. The aim of our study is to investigate the cardioprotective effects of sphingosine 1-phosphate receptor agonist fingolimod (FTY720) in global ischemia-reperfusion injury related to the cardiac arrest, cardiopulmonary bypass, and heart transplantation. Methods: In all the three experimental studies, global ischemia-reperfusion was achieved by cardiac arrest either by Ventricular fibrillation or cardioplegia (CPB HT) in anesthetized (sodium pentobarbital, 60 mg/ml/kg i.v) and ventilated male Sprague-Dawley rats (300 - 350 g). The global ischemic period lasted 10 min in the cardiac arrest and cardioplegic arrest, but in transplantation, ischemia time was 60 min while reperfusion times were maintained for either 60 min or 24 hours. Where applicable, monitoring was done using electrocardiogram and hemodynamic data recorded at baseline, 1 hour and 24 hours of reperfusion. The level of high energy phosphates was measured. Apoptotic, inflammatory and oxidative markers were analyzed. The statistical significance was considered as p ≤ 0.05. Experimental design: In all the above mentioned protocols, 10 animals were used in each of the control and treated groups. The first study examined the cardioprotective potential of fingolimod using the following treatment strategy, treatment administered (post ischemia) immediately at the early phase of reperfusion (fingolimod 1mg/kg i.v) compared to saline controls (0.9% saline). In next two experimental models, treatment administration was done 15 min before ischemic phase (fingolimod 1mg/kg i.v.) compared to controls (0.9% saline), followed by 10 min ischemia and 60 min reperfusion in cardioplegic arrest while 60 min ischemic phase remained from heart explantation to reperfusion, and reperfusion phase lasted for 24 hours following blood and tissue collection Results: Three experimental models demonstrated significant myocardial protection in Fingolimod treated groups as compared to control groups. Hemodynamic assessment showed improved cardiac function at late phase. Reduced frequency of apoptotic cells and inflammatory mediators were found in the treated group. High energy phosphates were preserved in the treated as compared to control groups. Reactive Oxygen Species (ROS) were also attenuated in the fingolimod-treated group. Increased phosphorylation of Akt and Erk1/2 signaling pathways found in fingolimod treated group as compared to control, these are important part of Reperfusion Injury Salvage Kinase (RISK) and Survivor Activating Factor Enhancement(SAFE) pathways. Conclusions: The intravenous administration of fingolimod in global ischemia-reperfusion was cardioprotective. Fingolimod cardioprotection appears to be mediated through preservation of high energy phosphates, reduction in oxidative stress, inhibition of apoptosis and inflammation leading to preserved cardiac functions. In summary, targeting sphingosine 1-phosphate receptors modulation may offer a new potential therapeutic cardioprotective agent to attenuate myocardial damage during global myocardial ischemia and reperfusion
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
LEFT ATRIAL APPENDAGE CLOSURE USING LEFT FEMORAL VEIN APPROACH
No full textAtrial Fibrillation (AF) is the most common tachyarrhythmia and is associated with major complications such as thromboembolic events. Anticoagulation therapy remains an important component of AF treatment to avoid thromboembolism. Left Atrial Appendage (LAA) closure may be considered in patients with AF with high stroke risk and contraindications for long term Oral Anti Coagulation (OAC) therapy. Devices for LAA closure are usually placed trans-septally using the Right Femoral Vein (RFV) approach (1). Alternative approaches for accessing the left atrium have been reported. (2) but there are no reports on usage of the Laft Femoral Vein (LFV) for LAA closure by using watchman device, that is unusual for septal puncture(3). In this report, we describe a LAA closure in a 83 year old patient using the LFV approach
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
