1,720,986 research outputs found
Ergosterol promotes neurite outgrowth, inhibits amyloid-beta synthesis, and extends longevity: In vitro neuroblastoma and in vivo Caenorhabditis elegans evidence
No full textAims: Alzheimer's disease (AD), the most common neurodegenerative disorder associated with aging, is characterized by amyloid-beta (A beta) plaques in the hippocampus. Ergosterol, a mushroom sterol, exhibits neuroprotective activities; however, the underlying mechanisms of ergosterol in promoting neurite outgrowth and preventing A beta associated aging have never been investigated. We aim to determine the beneficial activities of ergosterol in neuronal cells and Caenorhabditis elegans (C. elegans). Materials and methods: The neuritogenesis and molecular mechanisms of ergosterol were investigated in wildtype and A beta precursor protein (APP)-overexpressing Neuro2a cells. The anti-amyloidosis properties of ergosterol were determined by evaluating in vitro A beta production and the potential inhibition of A beta-producing enzymes. Additionally, AD-associated transgenic C. elegans was utilized to investigate the in vivo attenuating effects of ergosterol. Key findings: Ergosterol promoted neurite outgrowth in Neuro2a cells through the upregulation of the transmembrane protein Teneurin-4 (Ten-4) mRNA and protein expressions, phosphorylation of the extracellular signal-regulated kinases (ERKs), activity of cAMP response element (CRE), and growth-associated protein-43 (GAP-43). Furthermore, ergosterol enhanced neurite outgrowth in transgenic Neuro2A cells overexpressing either the wild-type APP (Neuro2a-APPwt) or the Swedish mutant APP (Neuro2a-APPswe) through the Ten-4/ ERK/CREB/GAP-43 signaling pathway. Interestingly, ergosterol inhibited A beta synthesis in Neuro2a-APPwt cells. In silico analysis indicated that ergosterol can interact with the catalytic sites of beta- and gamma-secretases. In A beta-overexpressing C. elegans, ergosterol decreased A beta accumulation, increased chemotaxis behavior, and prolonged lifespan. Significance: Ergosterol is a potential candidate compound that might benefit AD patients by promoting neurite outgrowth, inhibiting A beta synthesis, and enhancing longevity
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
Antioxidant effects of anthocyanins-rich extract from black sticky rice on human erythrocytes and mononuclear leukocytes
Get PDFThe present study was aimed at determining the optimum dose of anthocyanins-rich extract (ARE) from Thai pigmented rice for its antioxidant effects. Three different methods of antioxidant analysis [Oxygen Radical Absorbance Capacity (ORAC) assay, Folin Cioculteau Phenol (FCP) assay and Vanillin assay] were used and the results obtained were excellently correlated (r > 0.98). Among red rice, black rice and black sticky rice, black sticky rice had the highest antioxidant level within the range 1368.34 } 16.85 TE mM /kg dry mass, 922.03 } 3.84 mM GE/kg dry mass and 218.97 } 0.74 CE mM/kg dry mass, respectively. ARE with the highest antioxidant level was used in the following tests: Hemolysis test and Heinz body formation, which were used to assess the antioxidant activities of ARE on human erythrocytes, respectively. Comet assay was also used to assess the antioxidant activities of ARE on mononuclear leukocytes and it was found that the optimum dose of ARE (600 mg/L) inhibited hemolysis induced by 2,2'-Azobis(2-amidinopropane) dihydrochloride and Heinz body formation induced by Nacetylphenylhydrazine. Moreover, 200 - 1000 mg/L of ARE was able to inhibit hydrogen peroxideinduced genotoxicity in mononuclear leukocytes in a dose-dependent manner. Nevertheless, high dose of ARE (. 800 mg/L) induced cytotoxicity and genotoxicity by itself. The results strongly suggested that optimum dose of ARE was beneficial for health promotion by reducing oxidative stress in cellular model.Key words: Antioxidant, pigmented rice, comet assay, hemolysis, Heinz body
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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