914 resultados para HIV-1-INFECTED UGANDAN ADULTS


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Although some studies have shown diversity in HIV integrase (IN) genes, none has focused particularly on the gene evolving in epidemics in the context of recombination. The IN gene in 157 HIV-1 integrase inhibitor-naive patients from the Sao Paulo State, Brazil, were sequenced tallying 128 of subtype B (23 of which were found in non-B genomes), 17 of subtype F (8 of which were found in recombinant genomes), 11 integrases were BF recombinants, and 1 from subtype C. Crucially, we found that 4 BF recombinant viruses shared a recurrent recombination breakpoint region between positions 4900 and 4924 (relative to the HXB2) that includes 2 gRNA loops, where the RT may stutter. Since these recombinants had independent phylogenetic origin, we argue that these results suggest a possible recombination hotspot not observed so far in BF CRF in particular, or in any other HIV-1 CRF in general. Additionally, 40% of the drug-naive and 45% of the drug-treated patients had at least 1 raltegravir (RAL) or elvitegravir (EVG) resistance-associated amino acid change, but no major resistance mutations were found, in line with other studies. Importantly, V151I was the most common minor resistance mutation among B, F and BF IN genes. Most codon sites of the IN genes had higher rates of synonymous substitutions (dS) indicative of a strong negative selection. Nevertheless, several codon sites mainly in the subtype B were found under positive selection. Consequently, we observed a higher genetic diversity in the B portions of the mosaics, possibly due to the more recent introduction of subtype F on top of an ongoing subtype B epidemics and a fast spread of subtype F alleles among the B population.

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The HIV-1 subtype C has spread efficiently in the southern states of Brazil (Rio Grande do Sul, Santa Catarina and Parana). Phylogeographic studies indicate that the subtype C epidemic in southern Brazil was initiated by the introduction of a single founder virus population at some time point between 1960 and 1980, but little is known about the spatial dynamics of viral spread. A total of 135 Brazilian HIV-1 subtype C pol sequences collected from 1992 to 2009 at the three southern state capitals (Porto Alegre, Florianopolis and Curitiba) were analyzed. Maximum-likelihood and Bayesian methods were used to explore the degree of phylogenetic mixing of subtype C sequences from different cities and to reconstruct the geographical pattern of viral spread in this country region. Phylogeographic analyses supported the monophyletic origin of the HIV-1 subtype C clade circulating in southern Brazil and placed the root of that clade in Curitiba (Parana state). This analysis further suggested that Florianopolis (Santa Catarina state) is an important staging post in the subtype C dissemination displaying high viral migration rates from and to the other cities, while viral flux between Curitiba and Porto Alegre (Rio Grande do Sul state) is very low. We found a positive correlation (r(2) = 0.64) between routine travel and viral migration rates among localities. Despite the intense viral movement, phylogenetic intermixing of subtype C sequences from different Brazilian cities is lower than expected by chance. Notably, a high proportion (67%) of subtype C sequences from Porto Alegre branched within a single local monophyletic sub-cluster. These results suggest that the HIV-1 subtype C epidemic in southern Brazil has been shaped by both frequent viral migration among states and in situ dissemination of local clades.

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Background: The city of Sao Paulo has the highest AIDS case rate, with nearly 60% in Brazil. Despite, several studies involving molecular epidemiology, lack of data regarding a large cohort study has not been published from this city. Objectives: This study aimed to describe the HIV-1 subtypes, recombinant forms and drug resistance mutations, according to subtype, with emphasis on subtype C and BC recombinants in the city of Sao Paulo, Brazil. Study design: RNA was extracted from the plasma samples of 302 HIV-1-seropositive subjects, of which 211 were drug-naive and 82 were exposed to ART. HIV-1 partial pol region sequences were used in phylogenetic analyses for subtyping and identification of drug resistance mutations. The envelope gene of subtype C and BC samples was also sequenced. Results: From partial pol gene analyses, 239 samples (79.1%) were assigned as subtype B, 23 (7.6%) were F1, 16 (5.3%) were subtype C and 24 (8%) were mosaics (3 CRF28/CRF29-like). The subtype C and BC recombinants were mainly identified in drug-naive patients (72.7%) and the heterosexual risk exposure category (86.3%), whereas for subtype B, these values were 69.9% and 57.3%, respectively (p = 0.97 and p = 0.015, respectively). An increasing trend of subtype C and BC recombinants was observed (p < 0.01). Conclusion: The HIV-1 subtype C and CRFs seem to have emerged over the last few years in the city of Sao Paulo, principally among the heterosexual population. These findings may have an impact on preventive measures and vaccine development in Brazil.

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Introduction: Human T-cell lymphotropic virus type 1 (HTLV-1) infection is intractable and endemic in many countries. Although a few individuals have severe symptoms, most patients remain asymptomatic throughout their lives and their infections may be unknown to many health professionals. HTLV-1 can be considered a neglected public health problem and there are not many studies specifically on patients' needs and emotional experiences. Objective: To better understand how women and men living with HTLV-1 experience the disease and what issues exist in their healthcare processes. Methods: A qualitative study using participant observation and life story interview methods was conducted with 13 symptomatic and asymptomatic patients, at the outpatient clinic of the Emilio Ribas Infectious Diseases Institute, in Sao Paulo, Brazil. Results and Discussion: The interviewees stated that HTLV-1 is a largely unknown infection to society and health professionals. Counseling is rare, but when it occurs, focuses on the low probability of developing HTLV-1 related diseases without adequately addressing the risk of infection transmission or reproductive decisions. The diagnosis of HTLV-1 can remain a stigmatized secret as patients deny their situations. As a consequence, the disease remains invisible and there are potentially negative implications for patient self-care and the identification of infected relatives. This perception seems to be shared by some health professionals who do not appear to understand the importance of preventing new infections. Conclusions: Patients and medical staff referred that the main focus was the illness risk, but not the identification of infected relatives to prevent new infections. This biomedical model of care makes prevention difficult, contributes to the lack of care in public health for HTLV-1, and further perpetuates the infection among populations. Thus, HTLV-1 patients experience an "invisibility" of their complex demands and feel that their rights as citizens are ignored.

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The impact of Structured Treatment Interruption (STI) in peripheral blood mononuclear cell (PBMC) proviral reservoirs in 41 highly active antiretroviral therapy (HAART)-treated viremic individuals at baseline and 12 weeks after STI was determined using quantitative PCR (qPCR). Viral load increased 0.7 log(10) and CD4 decreased 97.5 cells/mm(3) after 12 weeks. A total of 28 of the 41 individuals showed an increased proviral load, 19 with a statistically significant increase above 10%. An increase in active viral replication is an important factor in the replenishment of the proviral reservoir even for short time periods.

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This work presents major results from a novel dynamic model intended to deterministically represent the complex relation between HIV-1 and the human immune system. The novel structure of the model extends previous work by representing different host anatomic compartments under a more in-depth cellular and molecular immunological phenomenology. Recently identified mechanisms related to HIV-1 infection as well as other well known relevant mechanisms typically ignored in mathematical models of HIV-1 pathogenesis and immunology, such as cell-cell transmission, are also addressed. (C) 2011 Elsevier Ltd. All rights reserved.

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Financial support: FUNDHERP, CTC, INCTC, FAPESP, CNPq and CAPES.

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Abstract Background The city of Sao Paulo has the highest AIDS case rate, with nearly 60% in Brazil. Despite, several studies involving molecular epidemiology, lack of data regarding a large cohort study has not been published from this city. Objectives This study aimed to describe the HIV-1 subtypes, recombinant forms and drug resistance mutations, according to subtype, with emphasis on subtype C and BC recombinants in the city of São Paulo, Brazil. Study design RNA was extracted from the plasma samples of 302 HIV-1-seropositive subjects, of which 211 were drug-naive and 82 were exposed to ART. HIV-1 partial pol region sequences were used in phylogenetic analyses for subtyping and identification of drug resistance mutations. The envelope gene of subtype C and BC samples was also sequenced. Results From partial pol gene analyses, 239 samples (79.1%) were assigned as subtype B, 23 (7.6%) were F1, 16 (5.3%) were subtype C and 24 (8%) were mosaics (3 CRF28/CRF29-like). The subtype C and BC recombinants were mainly identified in drug-naïve patients (72.7%) and the heterosexual risk exposure category (86.3%), whereas for subtype B, these values were 69.9% and 57.3%, respectively (p = 0.97 and p = 0.015, respectively). An increasing trend of subtype C and BC recombinants was observed (p < 0.01). Conclusion The HIV-1 subtype C and CRFs seem to have emerged over the last few years in the city of São Paulo, principally among the heterosexual population. These findings may have an impact on preventive measures and vaccine development in Brazil.

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The HAM/TSP caused by HTLV-1 infection usually affects patients to disabling states, and sometimes can lead them to paraplegia presenting symptoms of depression and anxiety, impacting on quality of life. Objective: The purpose of this study was to evaluate the frequency of depression and anxiety and its impact on quality of life in HTLV-1-infected TSP/HAM patients. Material and Methods: This was a cross-sectional study including 67 asymptomatic (control group) and 63 with TSP/HAM subjects. The instruments used were a demographic questionnaire, scales for anxiety and depression diagnosis (BDI and BAI), questionnaire for the assessment of Quality of Life of the World Health Organization (WHOQOL-Brief) and neurological scale to measure the disability level (Osame’s Disability Status Scale). All patients had HTLV-I diagnosis by serological and molecular approaches, monitored at Instituto de Infectologia Emílio Ribas from May 2008 to July 2009. Data were analyzed statistically by frequencies, the Mann-Whitney test and the Spearman correlation test. Data among groups were analyzed and correlated with functional and severity aspects. Results: The results showed that patients with HAM/TSP compared to asymptomatic carriers had higher rates of depression (p < 0.001) and anxiety (p < 0.001), and impairment on quality of life in the areas of: dissatisfaction with health (p < 0.001), physical (p < 0.001) and the environment (p = 0.003). The main factors that correlated with levels of depression and anxiety and the domains of the WHOQOL-brief were: education, family income and social class. Conclusion: A well conducted evaluation and counseling may help in treatment, for a better quality of life of these patients.

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Background Human T-cell lymphotropic virus type 1 (HTLV-1) infection can increase the risk of developing skin disorders. This study evaluated the correlation between HTLV-1 proviral load and CD4+ and CD8+ T cells count among HTLV-1 infected individuals, with or without skin disorders (SD) associated with HTLV-1 infection [SD-HTLV-1: xerosis/ichthyosis, seborrheic dermatitis or infective dermatitis associated to HTLV-1 (IDH)]. Methods A total of 193 HTLV-1-infected subjects underwent an interview, dermatological examination, initial HTLV-1 proviral load assay, CD4+ and CD8+ T cells count, and lymphproliferation assay (LPA). Results A total of 147 patients had an abnormal skin condition; 116 (79%) of them also had SD-HTLV-1 and 21% had other dermatological diagnoses. The most prevalent SD-HTLV-1 was xerosis/acquired ichthyosis (48%), followed by seborrheic dermatitis (28%). Patients with SD-HTLV-1 were older (51 vs. 47 years), had a higher prevalence of myelopathy/tropical spastic paraparesis (HAM/TSP) (75%), and had an increased first HTLV-1 proviral load and basal LPA compared with patients without SD-HTLV-1. When excluding HAM/TSP patients, the first HTLV-1 proviral load of SD-HTLV-1 individuals remains higher than no SD-HTLV-1 patients. Conclusions There was a high prevalence of skin disorders (76%) among HTLV-1-infected individuals, regardless of clinical status, and 60% of these diseases are considered skin disease associated with HTLV-1 infection.

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NLRP3-inflammasome activation was evaluated in monocyte-derived dendritic cells (DC) obtained through IL-4 (IL4-DC) or IFN-α (IFN-DC) protocols and pulsed with chemically inactivated HIV-1. Inflammasome' genes expression and IL-1β secretion were compared in DC isolated from 15 healthy subjects (HC) and 10 HIV-1 infected individuals (HIV+). FINDINGS: Whether HIV was able to increased NLRP3-inflammasome genes expression and IL-1β secretion in IL4-DC from HC, the induction of inflammasome appeared significantly reduced in IFN-DC from HC, suggesting a different responsive state of IFN-DC compared to IL4-DC. No inflammasome activation was observed in IL4-DC as well as in IFN-DC derived from HIV + subjects, confirming previous findings on "unresponsive" state of DC derived from HIV + possibly due to chronic inflammatory state of these individuals. CONCLUSIONS: Our results showed that IFN-α differently modulates inflammasome expression during monocytes-DC in vitro differentiation. These findings could be of interest considering the on-going research about DC manipulation and therapeutic strategies for HIV + involving DC-based immune-vaccines.

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Host determinants of HIV-1 viral tropism include factors from producer cells that affect the efficiency of productive infection and factors in target cells that block infection after viral entry. TRIM5 restricts HIV-1 infection at an early post-entry step through a mechanism associated with rapid disassembly of the retroviral capsid. Topoisomerase I (TOP1) appears to play a role in HIV-1 viral tropism by incorporating into or otherwise modulating virions affecting the efficiency of a post-entry step, as the expression of human TOP1 in African Green Monkey (AGM) virion-producing cells increased the infectivity of progeny virions by five-fold. This infectivity enhancement required human TOP1 residues 236 and 237 as their replacement with the AGM counterpart residues abolished the infectivity enhancement. Our previous studies showed that TOP1 interacts with BTBD1 and BTBD2, two proteins which co-localize with the TRIM5 splice variant TRIM5 in cytoplasmic bodies. Because BTBD1 and BTBD2 interact with one HIV-1 viral tropism factor, TOP1, and co-localize with a splice variant of another, we investigated the potential involvement of BTBD1 and BTBD2 in HIV-1 restriction.

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The M184V mutation decreases the replication capacity of HIV-1. This prospective study aimed to characterize the virologic and immunologic changes during monotherapy with lamivudine (3TC) in patients with limited options for a fully suppressive new therapy.

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Various patterns of HIV-1 disease progression are described in clinical practice and in research. There is a need to assess the specificity of commonly used definitions of long term non-progressor (LTNP) elite controllers (LTNP-EC), viremic controllers (LTNP-VC), and viremic non controllers (LTNP-NC), as well as of chronic progressors (P) and rapid progressors (RP).