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Influence of mismatch repair system and p53 on celi cycle perturbation, apoptosis and chromosomal damage induced by bleomycin
No full textThe antibiotic bleomycin (BLM) is an anticancer drug used for the treatment of a variety of tumors. Similarly to ionizing radiations, its cytotoxic activity is mainly related to the generation of oxygen radicals and, for this reason, BLM is classified as a radiomimetic agent. Here we describe the influence or either the mismatch repair system (MMR) or p53 on cell cycle alterations, apoptosis and chromosomal damage induced by BLM. The MMR-deficient colon carcinoma cell line HCTI16 and its MMR-proficient subline HCTlI6/3-6, both expressing wild-type p53,were transfected with a vector encoding a dominant-negative p53 mutant, or with an empty vector. Four transfected clones having the following phenotypes: MMR-proficient/p53 wild-type, MMR-proficient/p53 mutant, MMR-deficient/p53 wild-type and MMR-deficient/p53 mutant were selected and subjected to BLM treatment. Loss of p53 alone resulted in abrogation of BLM-induced G1 arrest and a higher accumulation of cells in the G2/M phase. Inactivation of p53 was also associated with increased cell sensitivity to apoptosis and chromosomal damage induced by the drug. Loss of MMR function alone was associated with increased cell resistance to G2/M arrest, apoptosis and chromosomal damage caused by bleomycin. Disabling both p53 and MMR function led to abrogation of BLM-induced G1 arrest and to impairment of drug-induced apoptosis, which was however less pronounced than that observed in the MMR deficient/p53 wild-type clone. Chromosomal damage in BLM-treated MMR-deficient clones was lower than in MMR-proficient ones both at 3 and 48 hours after treatment.
In conclusion, our data show that the functional status of both the MMR system and p53 influences cellular responses to bleomycin, being MMR-proficient/p53 mutant cells the most sensitive and MMR-deficient/p53 wild-type cells the most resistant to the drug
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
Apoptosi e danno cromosomico indotti da bleomicina: effetti del sistema di riparo degli appaiamenti erronei tra le basi e p53
No full textDispelling 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
PlGF induces melanoma resistance to temozolomide through a mechanism that involves NF-kB activation.
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