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Opposite effects of IFN-gamma on CCR5 and CXCR4 espression and on entry of M- and T-tropic HIV in epithelial cells
No full textIFN-alpha2b increases interleukin-10 expression in primary activated human CD8+ T cells
No full textInterleukin-10 (IL-10) is a multifunctional cytokine with diverse effects on most hematopoietic cell types. It appears the principal function of IL-10 is to limit and ultimately terminate inflammatory response. We demonstrate here that interferon-alpha2b (IFN-alpha) increases the expression of IL-10 in activated primary CD8(+) T cells. Optimal induction of mRNA expression and protein synthesis was observed when IFN-alpha was added to cells activated by the combination of anti-CD3 monoclonal antibody (mAb) and IL-2. Maximal stimulation of IL-10 protein production was observed after prolonged incubation periods (48-72 h). No effects were observed on the production of IL-4, whereas IFN-gamma was produced with a faster kinetics than an untreated control. Our data indicate that IFN-alpha promotes the development of a CD8(+) T cell population with enhanced anti-inflammatory activity, which may play a critical role in the regulation of a proper immune response
Optimizing Measures of Information Encoding in Astrocytic Calcium Signals
No full textWhile most models of brain information encoding focus on neurons, recent studies have shown that calcium dynamics of astrocytes, the major class of non-neural cells in the brain, can add information about key cognitive variables that is not found in the activity of nearby neurons. This raises the question of what could be the contribution of astrocytes in information processing, and calls for analysis tools to characterize this contribution. Here we construct simulations with realistic dependencies of astrocytic activity on external variables and we use these simulations to understand how to optimally set parameters of information theoretic analysis of astrocytic activities. Applications of our techniques to simulated and real astrocytic data show how to set parameters of information analyses that provide conservative, yet reliable, estimates of astrocytic calcium dynamics contribution to circuit-level brain information processing
Opposite effects of interferong on CCR5 and CXCR4 expression and on entry of M- and T-tropic HIV in epithelial cells
No full text
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
Engagement of CD28 modulates CXC chemokine receptor 4 surface expression in both resting and CD3-stimulated CD4+ T cells
No full textOptimal CD4+ T cell activation requires the cooperation of multiple signaling
pathways coupled to the TCR-CD3 complex and to the CD28 costimulatory molecule.
In this study, we have investigated the expression of surface CXC chemokine
receptor 4 (CXCR4) in enriched populations of CD4+ T PBL, stimulated with
anti-CD3 and anti-CD28 mAbs, immobilized on plastic. Anti-CD3 alone induced a
progressive down-regulation of surface CXCR4, accompanied by a significant
decline in the entry of the HXB2 T cell line-tropic (X4-tropic) HIV-1 clone in
CD4+ T cells. Of note, this effect was strictly dependent on the presence in
culture of CD14+ monocytes. On the other hand, anti-CD28 alone induced a small
but reproducible increase in the expression of surface CXCR4 as well as in the
entry of HXB2 HIV-1 clone in resting CD4+ T cells. When the two mAbs were used in
combination, anti-CD28 potently synergized with anti-CD3 in inducing the
expression of CD69 activation marker and stimulating the proliferation of CD4+ T
cells. On the other hand, anti-CD28 counteracted the CXCR4 down-modulation
induced by anti-CD3. The latter effect was particularly evident when anti-CD28
was associated to suboptimal concentrations of anti-CD3. Because CXCR4 is the
major coreceptor for the highly cytopathic X4-tropic HIV-1 strains, which
preferentially replicate in proliferating CD4+ T cells, the ability of anti-CD28
to up-regulate the surface expression of CXCR4 in both resting and activated CD4+
T cells provides one relevant mechanism for the progression of HIV-1 disease
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
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