Search results for "HIV"
showing 10 items of 1527 documents
Predictors of therapy failure in newly diagnosed pulmonary tuberculosis cases in Beira, Mozambique.
2018
Abstract Objective Tuberculosis (TB) remains a major global health issue, ranking in the top ten causes of death worldwide. A deep understanding of factors influencing poor treatment outcomes may allow the development of additional treatment strategies, focused on the most vulnerable groups. Aims of the study were: (i) to evaluate the treatment outcome among TB subjects followed in an outpatient setting and (ii) to analyze factors associated with treatment failure in newly diagnosed patients with pulmonary TB in Beira, the second largest city of Mozambique. Results A total of 301 TB adult patients (32.6% females) were enrolled. Among them, 62 (20.6%) experienced a treatment failure over a 6…
A novel methodology for large-scale phylogeny partition
2011
Understanding the determinants of virus transmission is a fundamental step for effective design of screening and intervention strategies to control viral epidemics. Phylogenetic analysis can be a valid approach for the identification of transmission chains, and very-large data sets can be analysed through parallel computation. Here we propose and validate a new methodology for the partition of large-scale phylogenies and the inference of transmission clusters. This approach, on the basis of a depth-first search algorithm, conjugates the evaluation of node reliability, tree topology and patristic distance analysis. The method has been applied to identify transmission clusters of a phylogeny …
Frequency-dependent selection in human immunodeficiency virus type 1.
2001
Genetic variation is the main evolutionary strategy adopted by RNA viruses and retroviruses. Evolution operates through competition between different individuals in the same environment, resulting in the imposition of the fittest variant. The process of competition could be affected by various factors, including the frequency of the different competing individuals. In order to investigate this aspect, individual virus populations derived from a human immunodeficiency virus type 1 isolate were studied at different competing proportions. The dynamics of variant imposition in each competition experiment permitted the detection of frequency-dependent selection (FDS); i.e. the imposition of vari…
Interplay between RNA structure and protein evolution in HIV-1.
2010
The genomes of many RNA viruses contain abundant secondary structures that have been shown to be important for understanding the evolution of noncoding regions and synonymous sites. However, the consequences for protein evolution are less well understood. Recently, the secondary structure of the HIV-1 RNA genome has been experimentally determined. Using this information, here we show that RNA structure and proteins do not evolve independently. A negative correlation exists between the extent of base pairing in the genomic RNA and amino acid variability. Relaxed RNA structures may favor the accumulation of genetic variation in proteins and, conversely, sequence changes driven by positive sel…
Evolutionary plasticity of SH3 domain binding by Nef proteins of the HIV-1/SIVcpz lentiviral lineage
2021
ABSTRACTThe accessory protein Nef of human and simian immunodeficiency viruses (HIV and SIV) is an important pathogenicity factor known to interact with cellular protein kinases and other signaling proteins. A canonical SH3 domain binding motif in Nef is required for most of these interactions. For example, HIV-1 Nef activates the tyrosine kinase Hck by tightly binding to its SH3 domain. An archetypal contact between a negatively charged SH3 residue and a highly conserved arginine in Nef (Arg77) plays a key role here. Combining structural analyses with functional assays, we here show that Nef proteins have also developed a distinct structural strategy - termed the “R-clamp” - that favors th…
Genotyping of a nosocomial outbreak of pandemic influenza A/H1N1 2009
2011
Background: Epidemiological surveys have revealed outbreaks of pandemic influenza A (H1N1) 2009 in several different contexts. Molecular characterization of the influenza virus could help to provide a more accurate description of these outbreaks. Objective: To genotype pandemic influenza A (H1N1) 2009 isolates from an epidemiologically defined nosocomial outbreak. Study design: We sequenced the neuraminidase (NA) and hemagglutinin (HA) influenza A (H1N1) 2009 genes from ten HIV-positive patients involved in an epidemiologically defined outbreak in the Clinical Microbiology and Infectious Diseases (CMID) Department. Sequences were aligned to search for specific genetic features of the involv…
Trends in HIV sexual prevention: Attitudinal beliefs and behavioral intention in Spanish young people over the past two decades (1999-2020).
2022
Abstract Despite preventive efforts, HIV exposure is still a concern for public health. The current prevalence is related to unsafe sex, which is based on socio-cognitive variables. Therefore, information about these variables is required to verify whether the past preventive strategies have been effective and improve the future ones. However, there is not updated information to adjust future preventive interventions. For this reason, this study analyzes trends by gender in Spanish young people over the past two decades in perceived susceptibility to HIV, severity perceived to HIV, condom confidence and the intention of condom use, from 1999 to 2020. For this purpose, 11,665 Spanish young p…
African and European HIV-positive women: psychological and psychosocial differences.
2000
The objectives were to study and compare the psychosocial and psychopathological aspects of HIV infection in African and European HIV-positive women living in France. All women included were seen in a semi-structured interview to assess personal history, history of their HIV infection, social and family relationships, preoccupation with childbearing and concerns about HIV infection and its prognosis. The comparison of psychological and psychosocial factors between HIV-positive African and European women showed certain significant differences. The demographic characteristics did not differ, except for current professional activity, with more African women being unemployed. The medical aspect…
Crecimiento postraumático en hombres gays con VIH en Buenos Aires, Argentina
2021
Este estudio cualitativo tuvo como objetivo explorar los significados atribuidos al virus de inmunodeficiencia humana (VIH) y la experiencia de cambios positivos posteriores al diagnóstico (crecimiento postraumático) en hombres gays de Buenos Aires, Argentina. Se efectuaron catorce entrevistas individuales en profundidad. Se implementó un análisis temático asignando códigos a fragmentos de transcripciones y organizándolos en temas. La edad media de los participantes fue de 41.29 (D.E.=11.97) y una media de 8.42 (D.E.=7.08) años desde el diagnóstico, tres de los cuales lo habían recibido en el último año. La mayoría informó cambios positivos que atribuyeron al diagnóstico de VIH, los que se …
Il Gran Caffè di Giuseppe Damiani Almeyda
2015
Il testo affronta lo studio di un’opera giovanile di Giuseppe Damiani Almeyda (1834-1911), figura di spicco del panorama architettonico in Sicilia tra la seconda metà dell’Ottocento ed i primi del Novecento. Il progetto del Gran Caffè, vincitore di prestigiosi riconoscimenti, anche se realizzato quando Damiani non era ancora trentenne, risulta molto maturo e segna una tappa importante nella formazione dell’architetto. Se ne ritroveranno richiami progettuali nel Politeama, edificio a cui il suo nome è legato, e in una grandiosa opera didattica, la Scuola Italiana di Architettura Civile, che, purtroppo, non è mai stata pubblicata. I disegni originali, a matita, inchiostro ed acquerello su car…