249 resultados para HIV Protease Inhibitors


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During the year of 2001, a retrospective, descriptive study in order to determine the influence of the antiretroviral therapy received by 111 HIV-HCV coinfected patients who had undergone at least one liver biopsy was conduced, 74 of them were treated with a protease inhibitor regimen (WPI), and 37 with a non-protease inhibitor regimen (NPI). The main characteristics found were: a young patient population (mean age 41 years old in both groups), composed in most part of male individuals (74.3% WPI and 51.4% NPI) with previous risk factors for both infections (WPI 93.2% and NPI 89.2%). The most significant findings included AIDS-defining disease (WPI 18.9% and NPI 13.5% of the cases), elevated hepatic enzyme levels (WPI: SGOT 52.1 and NPI 53.2), absence of liver disease-related symptoms (16.2% for both groups), average CD4 count > 350 for both groups (WPI 362.2 and NPI 378.1), predominantly low-grade fibrosis in both populations (0-2 in 63.6% of WPI patients and in 80% of NPI patients), with necro-inflammatory activity ranging from 5-7 in 51.3% and 42.9% of WPI patients and NPI patients, respectively. It is suggested a sequential biopsy to better evaluate the evolution of the hepatic disease, according to the HAART regimen received.

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The objective of this study is to identify subtypes of Human Immunodeficiency Virus type 1 (HIV-1) and to analyze the presence of mutations associated to antiretroviral resistance in the protease (PR) and reverse transcriptase (RT) regions from 48 HIV-1 positive treatment naïve patients from an outpatient clinic in Maringá, Paraná, Brazil. Sequencing was conducted using PR, partial RT and group-specific antigen gene (gag) nested PCR products from retrotranscribed RNA. Transmitted resistance was determined according to the Surveillance Drug Resistance Mutation List (SDRM) algorithm. Phylogenetic and SimPlot analysis of concatenated genetic segments classified sequences as subtype B 19/48 (39.6%), subtype C 12/48 (25%), subtype F 4/48 (8.3%), with 13/48 (27.1%) recombinant forms. Most recombinant forms were B mosaics (B/F 12.5%, B/C 10.4%), with one C/F (2.1%) and one complex B/C/F mosaic (2.1%). Low levels of transmitted resistance were found in this study, 2/48 (2.1% to NRTIs and 2.1% for PI). This preliminary data may subsidize the monitoring of the HIV evolution in the region.

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SUMMARY Combination Antiretroviral Therapy (cART) aims to inhibit viral replication, delay immunodeficiency progression and improve survival in AIDS patients. The objective of this study was to compare two different schemes of cART, based on plasma viral load (VL) and CD4+ T lymphocyte count, during 48 weeks of treatment. For this purpose, 472 medical charts of a Specialized Outpatient Service were reviewed from 1998 to 2005. Out of these, 58 AIDS patients who had received a triple drug scheme as the initial treatment were included in the study and two groups were formed: Group 1 (G1): 47 individuals treated with two nucleoside reverse-transcriptase inhibitors (NRTI) and one non-nucleoside reverse-transcriptase inhibitor; Group 2 (G2): 11 patients treated with two NRTI and one protease inhibitor. In G1 and G2, 53.2% and 81.8% respectively were patients with an AIDS-defining disease. The T CD4+ lymphocyte count increased progressively up until the 24th week of treatment in all patients, while VL became undetectable in 68.1% of G1 and in 63.6% of G2. The study concluded that the evolutions of laboratory tests were similar in the two treatment groups and that both presented a favorable clinical evolution.

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The colonization of the oral cavity is a prerequisite to the development of oropharyngeal candidiasis. Aims: The aims of this study were: to evaluate colonization and quantify Candida spp. in the oral cavity; to determine the predisposing factors for colonization; and to correlate the levels of CD4+ cells and viral load with the yeast count of colony forming units per milliliter (CFU/mL) in HIV-positive individuals treated at a University Hospital. Saliva samples were collected from 147 HIV patients and were plated on Sabouraud Dextrose Agar (SDA) and chromogenic agar, and incubated at 30 ºC for 72 h. Colonies with similar morphology in both media were counted and the result expressed in CFU/mL. Results: Of the 147 HIV patients, 89 had positive cultures for Candida spp., with a total of 111 isolates, of which C. albicans was the most frequent species (67.6%), and the mean of colonies counted was 8.8 × 10³ CFU/mL. The main predisposing factors for oral colonization by Candida spp. were the use of antibiotics and oral prostheses. The use of reverse transcriptase inhibitors appears to have a greater protective effect for colonization. A low CD4+ T lymphocyte count is associated with a higher density of yeast in the saliva of HIV patients.

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As lesões anorretais são comuns nos pacientes positivos para o vírus da imunodeficiência humana. A terapia antirretroviral de alta efetividade tem pouca influência na progressão das neoplasias anais. Estudou-se a prevalência das lesões anorretais em 88 pacientes HIV positivos atendidos no serviço de doenças infecto-parasitárias do Hospital Universitário de Brasília, em uso de terapia antirretroviral de alta efetividade. Dados sócio-demográficos foram coletados usando um questionário pré-elaborado e os pacientes foram submetidos a exame proctológico. Cerca de 71% relataram coito anal e 30,7% estavam em uso de inibidor de protease. A prevalência das lesões anorretais foi 36,4%, sendo as mais freqüentes: condiloma acuminado e fissura anal. O condiloma acuminado foi a lesão anorretal mais prevalente e teve associação com o uso de lopinavir/ritonavir. Sugere-se o rastreamento das lesões anorretais causadas pelo papilomavírus humano nos pacientes HIV positivos/AIDS em uso de inibidor de protease.

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INTRODUCTION: HIV-infected children and adolescents treated with highly active antiretroviral therapy (HAART) regimens that include a protease inhibitor (PI) can show significant improvements in clinical outcomes, nutritional status and quality of life. The study aimed to report nutritional and metabolic alterations for pediatric patients continuously exposed to HAART and for healthy controls for up to 1 year. METHODS: Clinical, anthropometric, lipid profile and food intake data were collected prospectively over approximately 12-months for each patient. RESULTS: Fifty-one individuals were studied, of these, 16 were healthy. After 12 months follow-up, HIV-positive individuals remained below the healthy control group parameters. No change was observed concerning food intake. Triglyceride serum levels were higher in patients using protease inhibitor at the onset of the study [PI groups: 114 (43 - 336), and 136 (63 - 271) versus control group: 54.5 (20 - 162); p = 0.003], but after twelve months follow-up, only the group using protease inhibitor for up to two months presented higher values [140 (73 - 273) versus 67.5 (33 - 117); p = 0.004]. HDL-cholesterol was lower in HIV-positive individuals [HIV-positive groups: 36 (27 - 58) and 36 (23 - 43); control 49.5 (34 - 69); p = 0.004]. CONCLUSIONS: HIV-infected children and adolescents treated with highly active antiretroviral therapy showed compromised nutritional parameters compared to a paired healthy control group. Individuals using protease inhibitor presented worse triglyceride serum levels compared to their healthy counterparts.

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FUNDAMENTO: Hipertensão arterial sistêmica (HAS) é fator de risco modificável, cujo controle pode reduzir doença cardiovascular nos pacientes com vírus da imunodeficiência adquirida (HIV). OBJETIVO: Estimar a prevalência de HAS e descrever as características dos pacientes com HAS e pré-hipertensão infectados pelo HIV/AIDS. MÉTODOS: Estudo seccional alinhado a uma coorte de pacientes com HIV/AIDS. Considerou-se hipertensão em níveis > 140/90 mmHg ou uso de anti-hipertensivos e pré-hipertensão em níveis > 120/80 mmHg. RESULTADOS: Dos 958 pacientes, 388 (40,5%) eram normotensos, 325 (33,9%) pré-hipertensos e 245 (25,6%) hipertensos. Desses 245 pacientes, 172 (70,2%) sabiam ser hipertensos e 36 (14,8%) apresentavam pressão arterial controlada. Tiveram diagnóstico de HAS após o diagnóstico do HIV 62 pacientes (54,4%). Lipodistrofia ocorreu em 95 (46,1%) dos pacientes, já sobrepeso/obesidade em 129 (52,7%). Utilização de antirretrovirais ocorreu em 184 (85,9%), 89 (41,6%) com inibidores de protease (IP) e 95 (44,4%) sem IP. Utilizavam antivirais > 24 meses 74,7%. Idade, antecedentes familiares de hipertensão, circunferência abdominal, índice de massa corporal e triglicerídeos foram maiores entre pacientes hipertensos. Tempo de infecção pelo HIV, contagem de linfócitos CD4, carga viral, tempo e tipo de esquema antirretroviral foram semelhantes nos hipertensos e pré-hipertensos. CONCLUSÃO: A elevada frequência de hipertensos não controlados e de riscos cardiovasculares nos infectados pelo HIV apontam a necessidade de medidas preventivas e terapêuticas contra HAS nesse grupo.

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We have examined by gelatin-SDS-PAGE the protease activity in cell lysates of Giardia duodenalis trophozoites of two axenic strains isolated in Brazil from a symptomatic patient (BTU-11) and an asymptomatic carrier (BTU-10), and the reference strain Portland 1 (P1). The proteolysis band patterns showed differences among strains isolated from asymptomatic and symptomatic individuals. The lysate of the strain BTU-10, showed only five hydrolysis bands, while a greater number of bands (10-11 bands) was seen in strains BTU-11 and P1. The protease activity in all lysates was inhibited by cysteine (E-64 and iodoacetamide) and serine proteases (TPCK and TLCK) inhibitors, but not by PMSF and EDTA. In general, the results revealed protease activities in G. duodenalis trophozoites of Brazilian axenic strains and the predominance of cysteine proteinases. It should be stressed the inter-strain difference in hydrolysis band patterns observed between strains isolated from symptomatic patients and the strain obtained from an asymptomatic carrier.

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In the context of universal access to antiretroviral therapy, the surveillance of human immunodeficiency virus type 1 (HIV-1) genetic diversity and resistance becomes pivotal. In this work our purpose was to describe the genetic variability; prevalence of drug-resistance mutations; and genotypic resistance profiles in HIV-1 infected individuals under antiretroviral treatment, from the Federal District, Brasília, Central Brazil. The entire viral protease and codons 19 to 234 of the reverse transcriptase gene from 45 HIV-1 isolates were amplified and sequenced for subtyping and genotyping. By phylogenetic analysis, 96% of the samples clustered with subtype B and the remaining 4% with HIV-1 subtype F sequences. One major protease inhibitor resistance-associated mutation, I50V, was detected in 38% of the samples. Minor mutations were also found at the protease gene: L10I/V (7%), K20M (2%), M36I (11%), L63P (20%), A71T (2%), and V77I (7%). Many mutations associated with reduced susceptibility to nucleoside or non-nucleoside reverse transcriptase inhibitors were detected: M41L (11%), E44D (4%), D67N (11%), T69D (2%), K70R (11%), L74V (2%), L100I (4%), K103N (18%), V118I (9%), Y181C (11%), M184V (18%), G190A (4%), T215Y (4%), and K219E (4%). This study has shown that 84% of the studied population from the Federal District, showing evidences of therapy failure, presented viral genomic mutations associated with drug resistance. The main antiretrovirals to which this population showed resistance were the PI amprenavir (38%), the NNRTIs delavirdine, nevirapine (31%), and efavirenz (24%), and the NRTIs lamivudine (18%), abacavir, and zidovudine (13%).

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Here we report the subcellular localization of an intracellular serine protease of 68 kDa in axenic promastigotes of Leishmania (Leishmania) amazonensis, using subcellular fractionation, enzymatic assays, immunoblotting, and immunocytochemistry. All fractions were evaluated by transmission electron microscopy and the serine protease activity was measured during the cell fractionation procedure using a-N-r-tosyl-L-arginine methyl ester (L-TAME) as substrate, phenylmethylsulphone fluoride (PMSF) and L-1-tosylamino-2-phenylethylchloromethylketone (TPCK) as specific inhibitors. The enzymatic activity was detected mainly in a membranous vesicular fraction (6.5-fold enrichment relative to the whole homogenate), but also in a crude plasma membrane fraction (2.0-fold). Analysis by SDS-PAGE gelatin under reducing conditions demonstrated that the major proteolytic activity was found in a 68 kDa protein in all fractions studied. A protein with identical molecular weight was also recognized in immunoblots by a polyclonal antibody against serine protease (anti-SP), with higher immunoreactivity in the vesicular fraction. Electron microscopic immunolocalization using the same polyclonal antibody showed the enzyme present at the cell surface, as well as in cytoplasmic membranous compartments of the parasite. Our findings indicate that the internal location of this serine protease in L. amazonensis is mainly restricted to the membranes of intracellular compartments resembling endocytic/exocytic elements.

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The hepatitis C virus (HCV) NS3 protease has been one of the molecular targets of new therapeutic approaches. Its genomic sequence variability in Brazilian HCV isolates is poorly documented. To obtain more information on the magnitude of its genetic diversity, 114 Brazilian HCV samples were sequenced and analysed together with global reference sequences. Genetic distance (d) analyses revealed that subtype 1b had a higher degree of heterogeneity (d = 0.098) than subtypes 1a (d = 0.060) and 3a (d = 0.062). Brazilian isolates of subtype 1b were distributed in the phylogenetic tree among sequences from other countries, whereas most subtype 1a and 3a sequences clustered into a single branch. Additional characterisation of subtype 1a in clades 1 and 2 revealed that all but two Brazilian subtype 1a sequences formed a distinct and strongly supported (approximate likelihood-ratio test = 93) group of sequences inside clade 1. Moreover, this subcluster inside clade 1 presented an unusual phenotypic characteristic in relation to the presence of resistance mutations for macrocyclic inhibitors. In particular, the mutation Q80K was found in the majority of clade 1 sequences, but not in the Brazilian isolates. These data demonstrate that Brazilian HCV subtypes display a distinct pattern of genetic diversity and reinforce the importance of sequence information in future therapeutic approaches.

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Reverse transcriptase (RT) is a multifunctional enzyme in the human immunodeficiency virus (HIV)-1 life cycle and represents a primary target for drug discovery efforts against HIV-1 infection. Two classes of RT inhibitors, the nucleoside RT inhibitors (NRTIs) and the nonnucleoside transcriptase inhibitors are prominently used in the highly active antiretroviral therapy in combination with other anti-HIV drugs. However, the rapid emergence of drug-resistant viral strains has limited the successful rate of the anti-HIV agents. Computational methods are a significant part of the drug design process and indispensable to study drug resistance. In this review, recent advances in computer-aided drug design for the rational design of new compounds against HIV-1 RT using methods such as molecular docking, molecular dynamics, free energy calculations, quantitative structure-activity relationships, pharmacophore modelling and absorption, distribution, metabolism, excretion and toxicity prediction are discussed. Successful applications of these methodologies are also highlighted.

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Leishmania causes tegumental and visceral diseases called leishmaniasis. Disease control is possible interrupting the transmission cycle, but HIV co-infection, chemotheraphy toxicity and lack of a vaccine are paramount difficulties. So, is necessary to study new Leishmania molecules and investigate the possibility to develop rational drugs using these molecules as targets. Leishmania express many peptidases during their life, and cysteine are the most abundant protease and many inhibitors were developed but failed to kill parasites. On the other hand, inhibitors of serine proteases killed promastigotes, indicating the possibility of these enzymes to be important targets in the development of anti-Leishmania drugs.

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OBJETIVO: descrever a diversidade genética dos isolados de HIV-1 de mulheres soropositivas acompanhadas em um centro de referência. MÉTODOS: estudo transversal, no qual foram incluídas 96 mulheres com dois testes sorológicos ELISA e um teste confirmatório Western Blot. Das amostras de sangue periférico, foram determinadas a carga viral pelo kit b-DNA e a contagem de linfócitos T CD4 e T CD8 pela citometria de fluxo excalibur. A extração e purificação do DNA pró-viral foi realizada pela reação em cadeia da polimerase (PCR), utilizando o kit QIAamp Blood (Qiagen Inc., Chatsworth, CA, USA). O sequenciamento da região pol foi realizado em 52 isolados com o (3100 Genetic Analyzer, Applied Biosystems Inc., Foster City, CA) e a genotipagem foi investigada pela ferramenta Rega (Rega Subtyping Tool). O padrão de resistência aos antirretrovirais (ARV) foi inferido pelo algoritmo do banco de dados Stanford HIV Resistance. Os estágios clínicos das participantes foram definidos como A, B ou C segundo os critérios do Center for Diseases Control (CDC). Para a análise estatística dos dados, foram utilizados os testes do χ2 para as variáveis categóricas e o teste t de Student para as variáveis numéricas. RESULTADOS: a média de idade da amostra, o tempo médio de doença e de tratamento foram: 33,7; 3,8 e 2,5 anos, respectivamente. A média da carga viral foi log10 2,3 cópias/mL; a dos linfócitos T CD4 e T CD8 foi 494,9 células/µL e 1126,4 células/µL. Sobre o estágio clínico, 30 mulheres estavam no estádio A, 47 no B e 19 no C. O sequenciamento dos 52 isolados encontrou 33 do subtipo B, quatro do F, um do C e 14 do recombinante BF. A análise da resistência aos ARV mostrou 39 (75,0%) isolados susceptíveis, 13 (25,0%) resistentes aos inibidores da transcriptase reversa (INTR) e três (5,7%) aos inibidores da protease (IP). CONCLUSÕES: Houve grande diversidade do HIV-1 e elevado percentual de isolados resistentes aos ARV na amostra estudada.

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Candidíase oral (CO) e leucoplasia pilosa (LP) são importantes indicadores da progressão da infecção pelo vírus da imunodeficiência humana (HIV) para o quadro de AIDS, principalmente em locais onde exames específicos são inacessíveis. OBJETO: Relacionar CO e LP ao número de células CD4+ e à carga viral (CV) em pacientes brasileiros HIV-positivos, confirmando-as como marcadores clínicos confiáveis de progressão da doença. FORMA DE ESTUDO: Coorte longitudinal. CASUÍSTICA E MÉTODO: Avaliamos prospectivamente 124 pacientes HIV-positivos, isentos de terapia antiretroviral. Todos foram submetidos a exame ORL, dosagem de células CD4+ e CV, sendo divididos em dois grupos: P e A, de acordo com a presença ou ausência de CO e LP. Depois de seis meses, os pacientes do grupo A foram subdivididos nos subgrupos P6 (presença de lesões) e A6. Dosamos novamente CD4+ e carga viral. Os resultados foram analisados estatisticamente. RESULTADOS: No grupo P (43 pacientes, 28 CO e 15 LP) a contagem de células CD4+ foi menor e a carga viral maior em relação ao grupo A (p<0,001). Após 6 meses, 15 dos 81 pacientes do grupo A foram excluídos por iniciarem terapia antiretroviral. Dezoito (11 CO e 7 LP), passaram a compor o grupo P6. Os demais, sem lesões, compuseram o grupo A6. A contagem de células CD4+ no grupo P6 foi menor (p< 0,001) que no grupo A6. O inverso ocorreu com a carga viral. DISCUSSÃO E CONCLUSÃO: CO e LP indicam contagem de células CD4+ abaixo de 300 cels/mm³ e carga viral elevada, sendo marcadores clínicos confiáveis da progressão da doença.