1,720,956 research outputs found
IL-12 and IL-7 synergise to control MAIT cell cytotoxic responses to bacterial infection
No full textBackgroundBacterial respiratory tract infections and exacerbations of chronic lung diseases are commonly caused by nontypeable Haemophilus influenzae (NTHi). Cell-mediated cytotoxicity may be key to controlling infection, but the responses of NTHi-specific T cell populations are not well understood. Mucosal-associated invariant T (MAIT) cells are a recently-discovered, innate-like subset of T cells with cytotoxic function, whose role in lung immunity is unclear. ObjectiveThe aim of this study was to determine the mechanisms behind conventional T and MAIT cell cytotoxic responses to NTHi. MethodsHuman ex vivo lung explants were infected with a clinical strain of NTHi. Monocyte-derived macrophages were also infected with NTHi in vitro and co-cultured with autologous T cells. Cytotoxic responses of T cell subsets were measured by flow cytometry. ResultsWe found significant upregulation of the cytotoxic markers, CD107a and granzyme B, in lung CD4+, CD8+ and MAIT cell populations. We show that MAIT cell cytotoxic responses were upregulated by a combination of both time-dependent antigen presentation and through a novel mechanism by which IL-12 and IL-7 synergistically control granzyme B through upregulation of the IL-12 receptor. ConclusionsOverall our data provide evidence for a cytotoxic role of MAIT cells in the lung and highlight important differences in the control of adaptive and innate-like T cell responses. Understanding these mechanisms may lead to new therapeutic opportunities to modulate the anti-bacterial response and improve clinical outcome. <br/
Human lung fibroblasts present bacterial antigen to autologous lung T helper cells
No full textLung fibroblasts are key structural cells that reside in the submucosa where they are in contact with large numbers of CD4+ T helper cells. During severe viral infection and chronic inflammation the submucosa is susceptible to bacterial invasion by lung microbiota such as Nontypeable Haemophilus influenzae (NTHi). Given their proximity in tissue, we hypothesised that human lung fibroblasts play an important role in modulating T helper cell responses to NTHi. We demonstrate that fibroblasts express the critical CD4+ T cell antigen-presentation molecule HLA-DR within the human lung, and that this expression can be recapitulated in vitro in response to interferon (IFN)?. Furthermore, we observed that cultured lung fibroblasts could internalize live NTHi. While unable to express CD80 and CD86 in response to stimulation, fibroblasts expressed the co-stimulatory molecules 4-1BBL, OX-40L and CD70, all of which are related to memory T cell activation and maintenance. CD4+ T cells isolated from the lung were predominantly (mean 97.5%) CD45RO+ memory cells. Finally, cultured fibroblasts activated IFN? and IL-17A cytokine production by autologous, NTHi-specific lung CD4+ T cells, and cytokine production was inhibited by a HLA-DR blocking antibody. These results indicate a novel role for human lung fibroblasts in contributing to responses against bacterial infection through activation of bacteria-specific CD4+ T cells
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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