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Exercise-induced apoptosis in rat kidney is mediated by both angiotensin II AT1 and AT2 receptors
No full textHistol Histopathol. 2006 May;21(5):459-66.
Exercise-induced apoptosis in rat kidney is mediated by both angiotensin II AT1 and AT2 receptors.
Podhorska-Okolow M, Dziegiel P, Gomulkiewicz A, Kisiela D, Dolinska-Krajewska B, Jethon Z, Carraro U, Zabel M.
Source
Department of Histology and Embryology, Medical University of Wroclaw, Wroclaw, Poland. [email protected]
Abstract
Excessive physical exercise may lead to disturbance of the entire homeostasis in the body, including damage not only in skeletal muscles but also in many distant organs. The mechanisms responsible for the exercise-induced changes could include oxidative stress or angiotensin II. We previously showed that acute exercise led to apoptosis in kidney but not as a result of oxidative stress. In this study, we examined the role of angiotensin II and its AT1 and AT2 receptors in mediation of exercise-induced apoptosis in kidney. We clearly demonstrated that acute physical exercise induced apoptosis in renal cells of distal convoluted tubuli and cortical and medullary collecting ducts. Moreover, the cells displayed an increased expression of both AT1 and AT2 angiotensin II receptors and of p53 protein. The results suggest that angiotensin II could upregulate p53 expression in renal distal convoluted tubular cells and in the cells collecting ducts via both AT1 and AT2 receptors, which might be the crucial apoptosis-mediating mechanism in kidneys after excessive exercise.
PMID:
16493576
[PubMed - indexed for MEDLINE
Effects of adaptive exercise on apoptosis in cells of rat renal tubuli.
No full textEur J Appl Physiol. 2007 Feb;99(3):217-26. Epub 2006 Nov 11.
Effects of adaptive exercise on apoptosis in cells of rat renal tubuli.
Podhorska-Okolow M, Dziegiel P, Murawska-Cialowicz E, Saczko J, Kulbacka J, Gomulkiewicz A, Rossini K, Jethon Z, Carraro U, Zabel M.
Source
Department of Histology and Embryology, Medical University of Wroclaw, Wroclaw, Poland. [email protected]
Abstract
Regular exercise is known to improve physiological and functional capacity of many organs due to adaptive processes. We have previously shown that acute exercise in untrained rats results in apoptosis of renal tubular cells and that the apoptotic process seems to be associated with stimulation of angiotensin II, AT1 and AT2 receptors. In this study, we examined the influence of regular training on apoptosis and the role of angiotensin II receptors and antioxidant enzymes in mediating the adaptive response in renal tubular cells. We measured apoptosis, expression of AT1 and AT2 receptors, level of lipid peroxidation (TBARS) and activities of antioxidant enzymes, SOD, GPx and CAT in kidneys of sedentary rats that were exposed to acute exercise and rats that were trained for 8 weeks. In untrained animals, the acute exercise resulted in increased apoptosis and increased expression of AT1 and AT2 receptors in renal tubular cells, while in the rats exposed to the 8-week regular training, there were no changes in apoptosis nor AT1 and AT2 receptor expression as compared to the sedentary animals. The TBARS levels were significantly increased in acutely exercised rats, while in rats pre-exposed to the training they remained unchanged. The acute exercise, as well as regular training, did not change SOD, CAT or GPx activities. These findings suggested that the acute exercise-induced apoptosis in renal tubules could involve action of AT1 and AT2 receptors as well as oxidative stress, while the regular training was shown to prevent apoptosis in renal tubular cells via modulated expression of AT1 and AT2 receptors.
PMID:
17102979
[PubMed - indexed for MEDLINE
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
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
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