1,720,954 research outputs found
YEAST AS A MODEL FOR THE STUDY OF HUMAN p53
No full textThe p53 tumor suppressor gene is a major barrier against cancer, preventing tumor development and promotes apoptosis induced by chemotherapy. P53 is able to regulate apoptosis both through its transcriptional activity and by the induction of the outer mitochondrial membrane (OMM) permeabilization promoting the release of cytochrome c.
In the yeast S. cerevisiae, the machinery of the basic apoptotic process seems to be conserved as it presents many of the cytological markers of apoptosis such as chromatin condensation, DNA fragmentation and the release of cytochrome c from mitochondria to the cytoplasm. It was recently reported that the expression of p53 in S. cerevisiae is able to activate the apoptotic processes, making this system a good model to analyze the basic mechanisms of apoptosis induced by p53.
It was recently identified a novel mutation in p53, in which lysine 351 is replaced by an asparagine (K351N) in a cisplatin-resistant ovarian carcinoma cell line (A2780 CIS). The K351N mutation is associated with the acquisition of resistance to apoptosis induced by cis-platinum in this cell line.
The K351N mutation significantly reduces the thermodynamic stability of p53 tetramers, the transcriptional activity of p53 and affects the export from the nucleus to the cytosol induced by cisplatinum treatment. The characterization of this mutant could thus help to envisage the development of new cancer drugs that can suppress this phenotype in tumors.
We cloned the two human genes, p53 and its mutated form p53K351N, under the control of Gal1-Gal10 vector and we transformed them in both wild type and S. cerevisiae strains mutated in genes involved in the apoptotic response. We then analyzed the effect of the p53 expression during an apoptotic stimulus (H2O2) and during aging
p53 death signal is mainly mediated by Nuc1(EndoG) in the yeast Saccharomyces cerevisiae
No full textThe tumor suppressor p53 plays a central role in the regulation of cellular growth and apoptosis. In the yeast Saccharomyces cerevisiae, the overexpression of the human p53 leads to growth inhibition and apoptotic cell death on minimal medium. In the present work, we show that p53-expressing cells are more susceptible to cell death after an apoptotic stimulus such as H2O2. The analysis of mutants involved in yeast apoptosis-like death suggests that the observed cell death is Yca1 independent and mainly mediated through Nuc1p. © 2013 Federation of European Microbiological Societies
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
