1,720,963 research outputs found
Cyanidin-3-O-glucoside exhibits anti-inflammatory properties and improves intestinal epithelial barrier integrity in Caco-2 cells exposed to TNF-alpha
No full textThe intestinal mucosal barrier plays an important role in the body’s protection against luminal pathogens and antigenic molecules; intercellular tight junctions (TJs), mainly composed of cytoplasmic proteins, including zona occludens (ZO) proteins, and two distinct transmembrane proteins, occludin and claudin, are the key structures responsible for intestinal epithelial barrier integrity (Turner, 2009). A dysregulation of one of this components, resulting in a paracellular permeability alteration, can lead to severe intestinal disorders, including inflammatory bowel disease (IBDs), the collective name for Crohn’s disease and ulcerative colitis, characterized by symptoms such as weight loss, diarrhoea, rectal bleeding, abdominal pain, fever and anemia (Cao et
al, 2013). TNF-α-induced increase in intestinal epithelial tight junction permeability has been proposed to be an important proinflammatory mechanism contributing to intestinal inflammation in IBD, as demonstrated by the presence of markedly elevated levels of this cytokine in the intestinal tissue and serum of patients suffering from Crohn's disease (Ye et al, 2006). Although the molecular mechanism involved in intestinal barrier dysfunction caused by proinflammatory cytokines is still unclear and it represents a research focus in pathogenesis of IBD, it has been believed that NF-kB plays a very important role in the proinflammatory cytokines induced intestinal barrier disruption and in a downregulation of tight junction proteins expression. Recent studies
support beneficial effects of anthocyanins, a class of flavonoid compounds that are widely
distributed in mediterranean diet, in various chronic inflammatory diseases, such as IBDs. The aim of this work was to determine some of the intracellular mechanisms involved in TNF-α modulation of intestinal epithelial permeability by using an in vitro intestinal epithelial system consisting of filter grown Caco-2 monolayers and the effects exerted by Cyanidin-3-O-glucoside (C3G) pretreatment. Caco-2 cells exposure to TNF-α for 6 h activated IKK/NF-kB proinflammatory pathway, and induced COX-2 and IL6 expression. Interestingly, cells pretreatment for 24h with C3G (20 and 40 μM) was effective in preventing TNF-α-induced changes. Furthermore, C3G was able to improve intracellular redox status altered by TNF-α by increasing GSH levels and cellular antioxidant power. Furthermore, TNF-α exposure for 6h altered Caco-2 cells barrier permeability and integrity. C3G pretreatment prevented the increase in Caco-2 TJ permeability and epithelial barrier integrity. In conclusion, C3G showed anti-inflammatory properties through the modulation of NF-kB pathway and improved intestinal epithelial barrier integrity altered by TNF-α in Caco-2 cells. These data suggest that anthocyanins could contribute, as complementary approaches to the conventional already existing therapeutic approaches (i.e. non-steroidal anti-inflammatory drugs), to the management of IBDs (Romier et al, 2008)
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
Cyanidin-3-O-glucoside inhibits NF-kB signalling in intestinal epithelial cells exposed to TNF-α and exerts protective effects via Nrf2 pathway activation
No full textChronic intestinal inflammatory disorders, such as Inflammatory Bowel Diseases (IBDs), are characterized by excessive release of proinflammatory mediators, intestinal barrier dysfunction and excessive activation of NF-kB cascade. Previous studies shown that TNF-α plays a central role in intestinal inflammation of IBDs and supported beneficial effects of flavonoids against chronic inflammatory diseases. In this study, we employed an in vitro model of acute intestinal inflammation using intestinal Caco-2 cells exposed to TNF-α. The protective effects of cyanidin-3-glucoside (C3G), an anthocyanin widely distributed in mediterranean diet, were then evaluated. Caco-2 cells exposure to TNF-α activated NF-kB proinflammatory pathway and induced IL6 and COX-2 expression. Cells pretreatment for 24h with C3G (20-40μM) prevented TNF-α-induced changes, and improved intracellular redox status. Our results demonstrated that C3G, also without any kind of stimulus, increased the translocation of the transcription factor Nrf2 into the nucleus so activating antioxidant and detoxifying genes. In conclusion, C3G exhibited protective effects through the inhibition of NF-kB signalling in Caco-2 cells and these beneficial effects appear to be due to its ability to activate cellular protective responses modulated by Nrf2. These data suggest that anthocyanins could contribute, as complementary or preventive approaches, to the management of chronic inflammatory diseases
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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