1,720,960 research outputs found
The Importance of a Proper Aetiological Diagnosis in the Management of Patients with Invasive Mycoses:A Case Report of a Brain Abscess by Scedosporium apiospermum
No full textRetrospective protein expression and epigenetic inactivation studies of CDH1 in patients affected by low-grade glioma.
No full textAberrant methylation of CpG islands in the promoter regions of tumour cells results in loss of gene function. In addition to genetic lesions, changes in the methylation profile of the promoters may be considered a factor for tumour-specific aberrant expression of the genes.We investigated the methylation status of E-cadherin gene (CDH1) promoter in low-grade glioma and correlated it with clinical outcome. Eighty-four cases of low-grade glioma (43 diffuse astrocytomas, 27 oligodendrogliomas and 14 oligoastrocytomas) with assessable paraffin-embedded tumour blocks and normal brain tissue, derived from non-cancerous tissue adjacent to tumour and commercially normal brain tissue, were collected, from which we determined CDH1 promoter methylation status and E-cadherin protein expression by methylation-specific polymerase chain reaction (MSP) and immunohistochemistry, respectively. CDH1 promoter was found hypermethylated in 54 out of 84 low grade gliomas (64%) compared with 84 normal brain tissue. CDH1 hypermethylation was found in 65% astrocytomas, 66% oligodendrogliomas and 57% oligoastrocytomas. A significant correlation between hypermethylation status, patient survival and progression-free survival was found (P = 0.04). Survival and progression-free survival were lower in patients with hypermethylated CDH1 promoter. We found that 15 astrocytomas, 9 oligodendrogliomas and 6 oligoastrocytomas were immunoreactive for E-cadherin. The incidence of loss of immunoreactivity for E-cadherin decreased significantly with age, overall survival and progression-free survival (P = 0.001, Kaplan-Meier test). We have demonstrated that CDH1 promoter hypermethylation significantly associated with down-regulated E-cadherin expression and overall survival of patients. This may have a bearing on the prognosis of low-grade glioma
miR-155 is up-regulated in primary and secondary glioblastoma and promotes tumour growth by inhibiting GABA receptors
Full text linkAn altered expression of microRNAs (miRNAs) contributes both to the development of cancer and to the progression of the disease. Malignant tumours and tumour cell lines have widespread deregulated expressions of miRNAs compared to normal tissues. In this study, we investigated the expression profiles of 340 mammalian miRNAs in 93 cases of multiform glioblastoma (primary and secondary glioblastoma tumours), by means of DNA microarrays. We show that the expression profiles of 10 miRNAs can distinguish primary from secondary glioblastoma types. Moreover, we found elevated miR-155 levels in primary and secondary glioblastoma tissues as well as in glioblastoma primary cultures. We hypothesised that γ-aminobutyric acid A receptor 1 (GABRA1) is a miR-155 target, and studied the correlation between miR-155 up-regulation and the GABRA1 protein in cultured glioblastoma cells by miRNA silencing. We show that a decrease in miR-155 expression to normal levels restores the expression of GABRA1, making glioblastoma cells sensitive to signals that inhibit cell proliferation mediated by GABRA1. In conclusion, the expression patterns of different miRNAs characterise primary and secondary glioblastomas. The aberrant overexpression of miR-155 contributes to the malignant phenotype of glioblastoma cells removing growth inhibition
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
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