1,721,066 research outputs found
Resistant viral variants in cellular reservoirs of human immunodeficiency virus infection
Full text linkSince the advent of antiretroviral therapy (ART), morbidity and mortality rates in those infected with human immunodeficiency virus type 1 (HIV-1) have been significantly reduced. However, HIV-1 is known to persist in several types of cells and tissues, and will usually return to pretreatment levels when therapy is stopped, even in those individuals who have been on suppressive ART for a long time. The discovery of drug sanctuaries and viral reservoirs in the body, in which HIV may persist, has helped to explain why therapeutic eradication of HIV-1 has proved so difficult. Several studies have indicated that the latent reservoir is an archive, composed of a mixture of wild-type and drug-resistant strains. Archived variants are assumed to remain life-long, thereby precluding the successful recycling of any drug towards which resistance has arisen. Several studies have underlined the value of pro-viral DNA as an additional source of information on the total burden of resistance in an individual. The HIV mutation patterns detected in plasma do not necessarily reflect those found in the cell-associated compartment, and may not be the same as those in different anatomical compartments. Although assessment of drug resistance in plasma is of direct and immediate importance for treatment, examination of the genotypic pattern of HIV-1 in cellular compartments might also provide information allowing a more sustainable response to therapy and better disease management
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
Lack of reduction of thymidine kinase activity in stavudine-treated HIV-infected patients
No full textIt has been demonstrated that prolonged in vivo or in vitro treatment with some nucleosides analogs may favor the selection of cells with a reduced activity of enzymes involved in the phosphorylation of these drugs leading to a reduced sensitivity to their antiretroviral action. The aim of this study was to evaluate the effect, in vivo, of zidovudine and stavudine treatment on thymidine kinase (TK) activity. The results obtained showed that TK levels in PBMC from naive patients and stavudine-treated patients did not significantly differ ( naive TK = 4.16 +/- 1.19 U/mg protein; stavudine TK = 3.65 +/- 1.73 U/mg protein; p = 0.42), suggesting that the treatment with this nucleoside analog is not associated to a defect of TK activity. On the contrary, PBMC from zidovudine-treated patients showed a significant reduction in TK activity compared to naive patients (naive TK = 4.16 +/- 1.19 U/mg protein; zidovudine TK = 2.70 +/- 1.54; p = 0.014. Although the clinical significance of these results has to be established, we can speculate that stavudine and zidovudine, which are presumably phosphorylated by the same cellular kinases, might display a different ability to in vivo select cells with a resistant phenotype
Inhibition of HIV type 1 BaL replication by MIP-1alpha, MIP-1beta, and RANTES in macrophages
No full textVariations 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
Reactivation of Toxoplasma gondii in HIV-infected population from rural area of Zimbabwe
No full textAppropriate 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
SARS-CoV-2 infection: diagnostic testing results occasionally require special attention
Full text linkThe case refers to a 51-year-old symptomatic man with a new SARS-CoV-2 RNA positive nasopharyngeal swab after two negative ones and the lack of significant development of antibody response measured by different diagnostic serological test. Our case underlines that a discrepancy between clinical course of SARS-CoV-2 infection and results from diagnostic tests may exist. This concept is rapidly emerging and supports the need for a deep knowledge of available and “in development” tests for a correct interpretation of their findings
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