1,721,172 research outputs found
Gene Expression Analysis of Chronically Inflamed and Healthy Human Periodontal Ligament Cells in vivo
No full textBackground: In the periodontium, the functions of the cell populations regarding the host-mediated tissue destruction in health and disease are not well understood. The purpose of this study was to measure the expression of genes differentially expressed in chronically inflamed periodontal ligament (PDL) cells compared to healthy PDL cells. Methods: We compared the genome-wide gene expressions of chronically inflamed and healthy PDL cells by microarray analysis, and validated the data by real-time RT-PCR to identify the genes that might play distinct roles in chronic periodontal disease in vivo. Results: The expression rates of 14,239 genes were investigated and 3,165 of them were found differentially expressed by at least two-fold; the expression rates of 1,515 genes were significantly upregulated and the expression rates of 1,650 genes were significantly downregulated in inflamed PDL cells. Conclusion: We focused on mainly structural components, for example, laminins and integrins, as well as degrading enzymes, for example, MMPs and cathepsins. The molecular composition of the laminin network varies in chronically inflamed compared to healthy PDL cells in vivo. Furthermore, integrin alpha6beta4, together with laminin-332, might be involved in chronic periodontal inflammation. Diverse keratins were upregulated, indicating that the epithelial cell rests of Malassez might also be involved in chronic periodontitis. The microarray analysis has identified a profile of genes potentially involved in chronic periodontal inflammation in vivo
Profiling of Differentially Expressed Genes in Peri-implantitis and Periodontitis in vivo by Microarray Analysis
No full textThe purpose of this study was to compare gene expression profiles of peri-implantitis and periodontitis to elucidate potential differences at the molecular level. With the help of microarray analysis, genome-wide gene expression of inflamed peri-implant granulation tissue, inflamed and healthy periodontal tissues (n=48 patients) were compared and the data were validated by real-time reverse transcription polymerase chain reaction. After highlighting different gene classes, we focused on the extracellular matrix-receptor interaction pathway and gene expression of extracellular matrix molecules, their receptors and matrix degrading enzymes. Only genes of non-fibril-forming collagens (types IV, VI, VII, and Q) were increased in peri-implantitis compared to periodontitis, whereas the expressions of two fibril-forming collagens (types III and K) were decreased in peri-implantitis, which suggested that peri-implant tissue re-models faster than periodontal tissue in vivo. Furthermore, cathepsin D and cathepsin S seem to participate in the destruction of peri-implant connective tissue. Despite their clinical similarities, the present investigation demonstrated that peri-implantitis and periodontitis are two different disease entities at least at the messanger ribonucleic acid level. The data provide insight for future studies aimed at dissecting the pathogenesis of peri-implant inflammation
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
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