1,720,984 research outputs found
Studies on the Development of Scarring Trachoma in Tanzania
Get PDFTrachoma is an ancient blinding disease which remains a public health and socio-economic threat to many communities, mainly in sub-Saharan Africa. Repeated conjunctival infection with Chlamydia trachomatis is thought to cause prolonged inflammation which leads to scarring and blindness, however, the disease is often found to progress in the absence of detected infection. Furthermore, despite apparently similar infection exposure, only some individuals progress to scarring. The relationship between infection and scarring progression and the immunopathological mechanisms underlying it are not clearly understood. A four-year longitudinal study was conducted in northern Tanzania in order to identify associations between C. trachomatis infection, conjunctival inflammation and immuno-fibrogenic gene expression with disease and scarring progression. Children aged 6-10 years at baseline were eligible for inclusion and 666 children were enrolled in the study. Participants were visited every three months for four years. Clinical signs and conjunctival swabs for C. trachomatis detection and immuno-fibrogenic gene expression by qPCR were collected at each time-point. Conjunctival photographs from baseline and final timepoints were graded and compared side-by-side to determine scarring incidence and progression. All community members were offered mass drug administration (MDA) with azithromycin for trachoma control annually for three years during the study. Host immuno-fibrogenic gene expression was profiled at the first five time-points. At baseline, host immune responses were analysed in relation to C. trachomatis infection, trachomatous inflammation – follicular (TF), papillary inflammation (TP) and scarring. Th1 and NK cell associated pathways were strongly associated with infection, suggesting their importance in the clearance of infection. Growth and matrix factors (MMPs) were strongly associated with the inflammation that persisted after infection was cleared (TF/TP), suggesting they might contribute to scarring development. Th17 pathway-associated cytokines were associated with infection and inflammation, therefore their contribution to protection versus pathology is unclear. The effect of azithromycin on inflammatory gene expression was investigated due to the reported immunomodulatory role of this antibiotic. Azithromycin treatment was found to have an anti-inflammatory effect on conjunctival gene expression, detectable three months posttreatment, suggesting that it may protect against pathological inflammation and therefore scarring development. The effect was gone by 6 months post treatment. Of the 448 children with outcome data, 103 (23.0%) had trachomatous scarring progression over the four-year study period. In 48 (10.7%) children this was incident scarring, whereas 55 (12.3%) had progression of pre-existing scarring. Scarring progression was strongly associated with papillary inflammation. Weaker associations between TF and C. trachomatis infection with scarring in univariate models were absent in a multivariable model adjusting for TP. These data suggest that the effect of infection and TF is mediated through TP, and that other factors contributing to the development of TP are important in driving scarring progression. Female sex was also associated with scarring progression. These findings suggest that the use of TP by trachoma control programs might be a more discriminating clinical marker to predict future scarring disease and requirements for trichiasis surgery than TF. In addition to clearing C. trachomatis infection, MDA might have an additional independent mechanism for reducing conjunctival inflammation, which may reduce subsequent risk of scarring progression
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
The conjunctival transcriptome in Ethiopians after trichiasis surgery: associations with the development of eyelid contour abnormalities and the effect of oral doxycycline treatment
No full textData includes: study ID, timepoint (in months), age, sex, trial arm, eyelid contour abnormalities (ECA) binary outcome, chlamydia detection (binary), qPCR cycle threshold values and qPCR delta cycle threshold values
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
Longitudinal gene expression dataset [The immuno-pathogenesis of progressive scarring trachoma: results of a four-year longitudinal study in Tanzanian children]
No full textLongitudinal data is provided for the following article "The immuno-pathogenesis of progressive scarring trachoma: results of a four-year longitudinal study in Tanzanian children"
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
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