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1.
HIV Med ; 19(2): 90-101, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28857427

RESUMO

OBJECTIVES: B-cell dysfunction and activation are thought to contribute to lymphoma development in HIV-positive people; however, the mechanisms are not well understood. We investigated levels of several markers of B-cell dysfunction [free light chain (FLC)-κ, FLC-λ, immunoglobulin G (IgG), IgA, IgM and IgD] prior to lymphoma diagnosis in HIV-positive people. METHODS: A nested matched case-control study was carried out within the EuroSIDA cohort, including 73 HIV-positive people with lymphoma and 143 HIV-positive lymphoma-free controls. Markers of B-cell dysfunction were measured in prospectively stored serial plasma samples collected before the diagnosis of lymphoma (or selection date in controls). Marker levels ≤ 2 and > 2 years prior to diagnosis were investigated. RESULTS: Two-fold higher levels of FLC-κ [odds ratio (OR) 1.84; 95% confidence interval (CI) 1.19, 2.84], FLC-λ (OR 2.15; 95% CI 1.34, 3.46), IgG (OR 3.05; 95% CI 1.41, 6.59) and IgM (OR 1.46; 95% CI 1.01, 2.11) were associated with increased risk of lymphoma > 2 years prior to diagnosis, but not ≤ 2 years prior. Despite significant associations > 2 years prior to diagnosis, the predictive accuracy of each marker was poor, with FLC-λ emerging as the strongest candidate with a c-statistic of 0.67 (95% CI 0.58, 0.76). CONCLUSIONS: FLC-κ, FLC-λ and IgG levels were higher > 2 years before lymphoma diagnosis, suggesting that B-cell dysfunction occurs many years prior to lymphoma development. However, the predictive value of each marker was low and they are unlikely candidates for risk assessment for targeted intervention.


Assuntos
Linfócitos B/imunologia , Linfócitos B/patologia , Infecções por HIV/complicações , Ativação Linfocitária , Linfoma/patologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Imunoglobulina G/sangue , Cadeias Leves de Imunoglobulina/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
2.
HIV Med ; 16(9): 533-43, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25988795

RESUMO

OBJECTIVES: The long-term side effects of stavudine (d4T) led to recommendations in 2009 to phase out use of this drug. We aimed to describe temporal patterns of d4T use across Europe. METHODS: Patients taking combination antiretroviral therapy (cART) in EuroSIDA with follow-up after 1 January 2006 were included in the study. cART was defined as d4T-containing [d4T plus at least two other antiretrovirals (ARVs) from any class] or non-d4T-containing (at least three ARVs from any class, excluding d4T). Poisson regression was used to describe temporal changes in the prevalence of d4T use and factors associated with initiating d4T. RESULTS: A total of 5850 patients receiving cART on 1 January 2006 were included in the current analysis, rising to 7768 patients on January 1 2013. During this time, the prevalence of d4T use fell from 11.2% to 0.7%, with an overall decline of 19% per 6 months [95% confidence interval (CI) 19-20%]. d4T use declined fastest in Northern Europe [26% (95% CI 23-29%) per 6 months], and slowest in Eastern Europe [17% (95% CI 16-19%) per 6 months]. In multivariable Poisson regression models, new d4T initiations decreased by 14% per 6 months [adjusted incidence rate ratio (aIRR) 0.86; 95% CI 0.80-0.91]. Factors associated with initiating d4T were residence in Eastern Europe (aIRR 4.31; 95% CI 2.17-9.98) versus other European regions and HIV RNA > 400 copies/mL (aIRR 3.11; 95% CI 1.60-6.02) versus HIV RNA < 400 copies/mL. CONCLUSIONS: d4T use has declined sharply since 2006 to low levels in most regions; however, a low but persistent level of d4T use remains in Eastern Europe, where new d4T initiations post 2006 are also more common. The reasons for the regional differences may be multifactorial, but it is important to ensure that all clinicians treating HIV-positive patients are aware of the potential harmful effects associated with d4T.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Estavudina/uso terapêutico , Adulto , Fármacos Anti-HIV/efeitos adversos , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Europa (Continente) , Feminino , Seguimentos , HIV-1/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Viral/análise , RNA Viral/efeitos dos fármacos , Análise de Regressão , Estavudina/efeitos adversos
3.
Curr Microbiol ; 68(2): 199-203, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24077953

RESUMO

This study provides a comprehensive picture of the C. neoformans/C. gattii molecular types most often associated with human cryptococcosis in Portugal and assesses the impact of C. gattii in these infections. One hundred and twenty-two clinical isolates, from distinct patients, were identified as C. neoformans and genotyped by URA5-RFLP, with the molecular types VNI (45.5 %) and VNIII (30.9 %) being the most commonly found ones. The molecular types VNII (11.4 %) and VNIV (11.4 %) were less abundant. One patient was found to be infected with a VGII isolate. This patient exhibited unusual clinical symptoms of cryptococcosis, reinforcing the suspicion for the presence of a different genotypic pattern, as determined afterwards. This case was detected in 2007 and is the first report of a potential autochthonous C. gattii infection case in Portugal, as the patient revealed no historical record of travelling outside the country.


Assuntos
Criptococose/microbiologia , Cryptococcus neoformans/genética , Cryptococcus/genética , Genótipo , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Adulto , Idoso , Cryptococcus/isolamento & purificação , Cryptococcus neoformans/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Adulto Jovem
4.
Rev Port Pneumol ; 19(3): 129-33, 2013.
Artigo em Inglês, Português | MEDLINE | ID: mdl-23669438

RESUMO

It is well established that HIV patients are at high risk of opportunistic infections (OI), like the ones caused by Pneumocystis jirovecii, a worldwide pathogen implicated in interstitial pneumonia (PcP). We present a case of a newly diagnosed HIV-1 patient with multiple OI, including a persistent form of PcP, an invasive aspergillosis (IA), cytomegalovirus and Mycobacterium xenopi lung infection. We describe the combination of laboratorial screening, surgery and antimicrobial therapy that were crucial for patient recovery.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/complicações , Soropositividade para HIV/complicações , Pneumocystis carinii , Pneumonia por Pneumocystis/complicações , Humanos , Masculino , Pessoa de Meia-Idade
5.
Clin Microbiol Infect ; 18(6): E177-84, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22487139

RESUMO

Specific single-nucleotide polymorphisms (SNPs) are recognized as important DNA sequence variations influencing the pathogenesis of Pneumocystis jirovecii and the clinical outcome of Pneumocystis pneumonia, which is a major worldwide cause of illness among immunocompromised patients. Genotyping platforms for pooled DNA samples are promising methodologies for genetic characterization of infectious organisms. We have developed a new typing strategy for P. jirovecii, which consisted of DNA pools prepared according to clinical data (HIV diagnosis, microscopic and molecular detection of P. jirovecii, parasite burden, clinical diagnosis and follow-up of infection) from individual samples using quantitative real-time PCR followed by multiplex-PCR/single base extension (MPCR/SBE). The frequencies of multiple P. jirovecii SNPs (DHFR312, mt85, SOD215 and SOD110) encoded at three distinct loci, the dihydrofolate reductase (DHFR), the mitochondrial large-subunit rRNA (mtLSU rRNA) and the superoxide dismutase (SOD) loci, were estimated in seven DNA pooled samples, representing a total of 100 individual samples. The studied SNPs were confirmed to be associated with distinct clinical parameters of infection such as parasite burden and follow-up. The MPCR/SBE-DNA pooling methodology, described in the present study, was demonstrated to be a useful high-throughput procedure for large-scale P. jirovecii SNPs screening and a powerful tool for evaluation of clinically relevant SNPs potentially related to parasite burden, clinical diagnosis and follow-up of P. jirovecii infection. In further studies, the candidate SNPs mt85, SOD215 and SOD110 may be used as molecular markers in association with MPCR/SBE-DNA pooling to generate useful information for understanding the patterns and causes of Pneumocystis pneumonia.


Assuntos
Tipagem Molecular/métodos , Técnicas de Tipagem Micológica/métodos , Micologia/métodos , Pneumocystis carinii/classificação , Pneumocystis carinii/genética , Adulto , Análise por Conglomerados , DNA Fúngico/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Pneumocystis carinii/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos
6.
J Clin Microbiol ; 49(5): 1810-5, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21389160

RESUMO

Pneumocystis jirovecii pneumonia (PcP) is a major cause of respiratory illness in patients with AIDS. The identification of multiple single-nucleotide polymorphisms (SNPs) at three distinct P. jirovecii loci encoding dihydrofolate reductase (DHFR), mitochondrial large-subunit rRNA (mtLSU rRNA), and superoxide dismutase (SOD) was achieved using multiplex-PCR (MPCR) followed by direct sequencing and two single-base extension (SBE) techniques. Four SNPs (DHFR312, mt85, SOD215, and SOD110), correlated previously with parameters of disease, were amplified and genotyped simultaneously. The concordance of results between the standard sequencing technique (direct sequencing) and SBE analysis was 96.9% for the acrylamide gel electrophoresis and 98.4% for the capillary electrophoresis. The cross-genetic analysis established several statistical associations among the SNPs studied: mt85C-SOD110T, SOD110T-SOD215C, and SOD110C-SOD215T. These results were confirmed by cluster analysis. Data showed that among the isolates with low to moderate parasite burden, the highest percentages of DHFR312C, mt85C, SOD110T, and SOD215C were detected, whereas for high parasite burden cases the highest frequencies were observed among isolates with DHFR312T, mt85T, SOD110C, and SOD215T. The polymorphisms studied were shown to be suitable genetic targets potentially correlated with PcP clinical data that can be used as predictors of outcome in further studies to help clinical decision-making in the management of PcP. The MPCR/SBE protocol described for the first time in the present study was shown to be a rapid, highly accurate method for genotyping P. jirovecii SNPs encoded by different loci that could be used for epidemiological studies and as an additional procedure for the prognostic classification and diagnosis of PcP.


Assuntos
Técnicas Microbiológicas/métodos , Técnicas de Tipagem Micológica/métodos , Pneumocystis carinii/classificação , Pneumocystis carinii/genética , Pneumonia por Pneumocystis/microbiologia , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Nucleotídeo Único , Adulto , Análise por Conglomerados , DNA Mitocondrial/genética , DNA Ribossômico/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular/métodos , Pneumocystis carinii/isolamento & purificação , Pneumonia por Pneumocystis/diagnóstico , RNA Ribossômico 23S/genética , Superóxido Dismutase/genética , Tetra-Hidrofolato Desidrogenase/genética
7.
Virology ; 408(2): 174-82, 2010 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-20947116

RESUMO

The human immunodeficiency virus replication cycle begins by sequential interactions between viral envelope glycoproteins with CD4 molecule and a member of the seven-transmembrane, G-protein-coupled, receptors' family (coreceptor). In this report we focused on the contribution of CCR8 as alternative coreceptor for HIV-1 and HIV-2 isolates. We found that this coreceptor was efficiently used not only by HIV-2 but particularly by HIV-1 isolates. We demonstrate that CXCR4 usage, either alone or together with CCR5 and/or CCR8, was more frequently observed in HIV-1 than in HIV-2 isolates. Directly related to this is the finding that the non-usage of CXCR4 is significantly more common in HIV-2 isolates; both features could be associated with the slower disease progression generally observed in HIV-2 infected patients. The ability of some viral isolates to use alternative coreceptors besides CCR5 and CXCR4 could further impact on the efficacy of entry inhibitor therapy and possibly also in HIV pathogenesis.


Assuntos
HIV-1/fisiologia , HIV-1/patogenicidade , HIV-2/fisiologia , HIV-2/patogenicidade , Receptores CCR8/fisiologia , Receptores de HIV/fisiologia , Antagonistas dos Receptores CCR5 , Linhagem Celular , Estudos de Coortes , Infecções por HIV/fisiopatologia , Infecções por HIV/virologia , HIV-1/isolamento & purificação , HIV-2/isolamento & purificação , Humanos , Técnicas In Vitro , Receptores CCR5/fisiologia , Receptores CCR8/antagonistas & inibidores , Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/fisiologia , Receptores de HIV/antagonistas & inibidores , Especificidade da Espécie , Replicação Viral/fisiologia
8.
Acta Reumatol Port ; 35(2): 259-63, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20711100

RESUMO

We present a case of a previously asymptomatic 34-year-old man that presented to the emergency department with two weeks of fever, arthralgia of the wrists and knees and sore throat. He was diagnosed with cytomegalovirus (CMV) mononucleosis. The patient remained symptomatic in the 5 following months. After an extensive workup to exclude other clinical conditions, a liver biopsy was performed and CMV hepatitis was diagnosed. He started valganciclovir therapy. Approximately one year after the initial complaints, the patient remained ill and presented clinical criteria compatible with Adult Onset Still's Disease. The patient had a marked improvement after institution of prednisolone, an effect that has been sustained during the following months.


Assuntos
Infecções por Citomegalovirus/complicações , Mononucleose Infecciosa/complicações , Doença de Still de Início Tardio/etiologia , Adulto , Humanos , Masculino
9.
Int J STD AIDS ; 21(4): 265-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20378898

RESUMO

Chlamydia trachomatis, serovar L2, is the causative agent of lymphogranuloma venereum (LGV), which during recent years has been responsible for various outbreaks reported among men who have sex with men (MSM) in Western Europe, America, Canada and Australia. Samples from nine patients with chronic proctitis, seen at a local hospital were sent to us for identification of C. trachomatis serovar L2. The presence of C. trachomatis serovar L DNA was identified by realtime polymerase chain reaction (PCR) in two patients. They both had high positive C. trachomatis antibody titres (>/=10,000) and were found to be infected with serovar L2b by sequencing after amplification of the omp 1 gene by a nested PCR technique. These two individuals met the diagnostic criteria for LGV serovar L2b infection and, to our knowledge, these are the first cases described in Portugal.


Assuntos
Chlamydia trachomatis/classificação , Chlamydia trachomatis/isolamento & purificação , Linfogranuloma Venéreo/diagnóstico , Linfogranuloma Venéreo/microbiologia , Proctite/microbiologia , Adulto , Anticorpos Antibacterianos/sangue , Chlamydia trachomatis/imunologia , DNA Bacteriano/análise , Infecções por HIV/complicações , Homossexualidade Masculina , Humanos , Incidência , Linfogranuloma Venéreo/epidemiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Portugal , Proctite/diagnóstico , Proctite/epidemiologia , Doenças Retais/diagnóstico , Doenças Retais/epidemiologia , Doenças Retais/microbiologia , Sorotipagem
10.
Clin Microbiol Infect ; 16(7): 878-84, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19719744

RESUMO

Pneumocystis jirovecii is a poorly understood pathogen that causes opportunistic pneumonia (Pneumocystis pneumonia (PcP)) in patients with AIDS. The present study was aimed at correlating genetic differences in P. jirovecii isolates and clinical patient data. A description of genetic diversity in P. jirovecii isolates from human immunodeficiency virus-positive patients, based on the identification of multiple single-nucleotide polymorphisms (SNPs) at five distinct loci encoding mitochondrial large-subunit rRNA (mtLSU rRNA), cytochrome b (CYB), superoxide dismutase (SOD), dihydrofolate reductase (DHFR), and dihydropteroate synthase (DHPS), was achieved using PCR with DNA sequencing and restriction fragment length polymorphism analysis. The statistical analysis revealed several interesting correlations among the four most relevant SNPs (mt85, SOD110, SOD215, and DHFR312) and specific clinical parameters: mt85C was associated with undiagnosed or atypical PcP episodes and favourable follow-up; SOD215C was associated with favourable follow-up; and DHFR312T was associated with PcP cases presenting moderate to high parasite burdens. The genotypes mt85C/SOD215C and SOD110T/SOD215C were found to be associated with less virulent P. jirovecii infections, whereas the genotype SOD110T/SOD215T was found to be related to more virulent PcP episodes. The present work demonstrated that potential P. jirovecii haplotypes may be related to the clinical data and outcome of PcP.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/microbiologia , DNA Fúngico/genética , Pneumocystis carinii/genética , Pneumonia por Pneumocystis/microbiologia , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Sequência de Bases , Citocromos b/genética , DNA Fúngico/análise , Di-Hidropteroato Sintase/genética , Feminino , Amplificação de Genes , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Tipagem Micológica , Pneumocystis carinii/isolamento & purificação , Reação em Cadeia da Polimerase , Portugal , RNA/genética , RNA Mitocondrial , Análise de Sequência de DNA , Superóxido Dismutase/genética , Tetra-Hidrofolato Desidrogenase/genética , Adulto Jovem
11.
J Hosp Infect ; 73(1): 15-23, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19647337

RESUMO

Isolation of patients with highly infectious diseases (HIDs) in hospital rooms with adequate technical facilities is essential to reduce the risk of spreading disease. The European Network for Infectious Diseases (EUNID), a project co-funded by European Commission and involving 16 European Union member states, performed an inventory of high level isolation rooms (HIRs, hospital rooms with negative pressure and anteroom). In participating countries, HIRs are available in at least 211 hospitals, with at least 1789 hospital beds. The adequacy of this number is not known and will depend on prevailing circumstances. Sporadic HID cases can be managed in the available HIRs. HIRs could also have a role in the initial phases of an influenza pandemic. However, large outbreaks due to natural or to bioterrorist events will need management strategies involving healthcare facilities other than HIRs.


Assuntos
Doenças Transmissíveis/transmissão , Instalações de Saúde/estatística & dados numéricos , Hospitais de Isolamento/estatística & dados numéricos , Isolamento de Pacientes/métodos , Bioterrorismo , Surtos de Doenças/prevenção & controle , União Europeia , Humanos
12.
Virus Res ; 142(1-2): 41-50, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19200444

RESUMO

We have previously shown the existence of primary human immunodeficiency virus type 2 isolates (MIC97 and MJC97) unable to use major coreceptors to entry into peripheral blood mononuclear cells, including CCR5 and CXCR4. We have now created a set of chimeric viruses derived from HIV-2(ROD), to study the contribution of env gene products in chemokine receptors usage and replication kinetics phenotype. The results obtained indicate that an env gene fragment, corresponding to the C1-C4 region of SU glycoprotein of both MIC97 and MJC97, impair efficient utilization of the major HIV coreceptors CCR5 and CXCR4 in phytohemagglutinin-stimulated peripheral blood mononuclear cells by ROD-MIC97 and ROD-MJC97 chimeric viruses. It also disrupts the ability to utilize established coreceptors for viral entry into GHOST-CD4 coreceptor-expressing cell lines. Resistance to CCR5 and CXCR4 inhibitors, as well as the ability to infect Delta32/Delta32ccr5 PBMC, was also observed in recombinant viruses containing the C1-C4 region from either MIC97 or MJC97. We also show that the presence of the TM region of env gene from MIC97 and MJC97 is sufficient to reduce viral replicative kinetics of ROD strain, indicating that this region, despite the presence and contribution of ROD genetic backbone, has an important role in viral progeny production efficiency.


Assuntos
Quimera/fisiologia , Infecções por HIV/metabolismo , HIV-2/fisiologia , Receptores CCR5/metabolismo , Receptores CXCR4/metabolismo , Internalização do Vírus , Linhagem Celular , Células Cultivadas , Quimera/genética , Produtos do Gene env , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-2/genética , Humanos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Ligação Proteica , Receptores CCR5/genética , Receptores CXCR4/genética
13.
Euro Surveill ; 13(50)2008 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-19087868

RESUMO

We describe two cases of lymphogranuloma venereum (LGV) in men who have sex with men in Portugal in 2008. These first two confirmed cases of LGV L2b proctitis in Portugal highlight the need for an enhanced surveillance programme in Portugal.


Assuntos
Surtos de Doenças/estatística & dados numéricos , Linfogranuloma Venéreo/epidemiologia , Vigilância da População , Doenças Retais/epidemiologia , Humanos , Incidência , Masculino , Portugal/epidemiologia , Fatores de Risco
14.
Scand J Infect Dis ; 37(10): 766-71, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16191898

RESUMO

In the present study, in order to improve the detection of Pneumocystis jirovecii dihydropteroate synthase (DHPS) mutations in pulmonary specimens of HIV-infected patients with P. jirovecii pneumonia, we evaluated a microfiltration procedure for the removal of human cell contamination and a nested-PCR method, for amplification in specimens with low parasite load. In the studied population, PCR amplification of the DHPS gene was more successful in unfiltered than in filtered specimens, with both touchdown-PCR and nested-PCR procedures (p<0.05 and p<0.001, respectively), but the amount of host DNA in the samples analysed seems to be inversely related with the successful PCR parasite detection. Amplification of P. jirovecii DHPS gene with nested-PCR was achieved in 77.5% of the specimens studied, demonstrating that this is a useful method for the identification of mutations in pulmonary specimens, including samples with low parasite loads, and will facilitate the evaluation of the relationship between the P. jirovecii DHPS polymorphisms and clinical resistance to sulfa drugs.


Assuntos
Di-Hidropteroato Sintase/genética , Pneumocystis carinii/enzimologia , Pneumonia por Pneumocystis/microbiologia , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético , Líquido da Lavagem Broncoalveolar/microbiologia , DNA Fúngico/análise , Filtração/métodos , Humanos , Mutação , Pneumocystis carinii/genética , Escarro/microbiologia
16.
Virology ; 313(1): 136-46, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12951028

RESUMO

In vivo, human immunodeficiency virus type 2 (HIV-2) infection reveals several unique characteristics when compared to HIV-1 infection, the most remarkable of which is the extraordinarily long asymptomatic period. Here we describe two HIV-2 primary isolates, obtained from asymptomatic individuals, which do not infect any coreceptor-expressing cell lines tested. In those cells, we show that the absence of replication is directly related to cell entry events. Furthermore, productive infection observed in peripheral blood mononuclear cells (PBMC) was not inhibited by natural ligands and monoclonal antibodies directed to CCR5 and CXCR4. Finally, viral entry efficiency and viral progeny production of these viruses are markedly impaired in PBMC, indicating a reduced replicative fitness of both viruses. In conclusion, our data suggest that in some HIV-2 asymptomatic individuals, the circulating viruses are unable to use the major coreceptors to infect PBMC. This fact should have important implications in HIV-2 pathogenesis and transmission.


Assuntos
Infecções por HIV/virologia , HIV-2/fisiologia , Receptores CCR5/fisiologia , Receptores CXCR4/fisiologia , Antígenos CD4/imunologia , Linhagem Celular , Infecções por HIV/imunologia , HIV-2/isolamento & purificação , Humanos , Leucócitos Mononucleares/imunologia , Receptores CXCR4/imunologia , Replicação Viral
17.
J Med Virol ; 61(1): 111-6, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10745242

RESUMO

The human immunodeficiency virus type 2 (HIV-2) is responsible for 4. 5% of AIDS cases in Portugal. Six HIV-2 subtypes have been described so far, subtype A being proposed as more pathogenic than the rest. The relationship between the clinical status and levels of both cellular and plasma HIV-2 viraemia is not well known, nor their modifications under antiretroviral therapy. Thirty-two consecutive HIV-2 infected persons (17 men, 15 women) attending two different hospitals in Lisbon in 1997 were enrolled prospectively in the study. All but 4 individuals most likely acquired the infection through heterosexual contact. More than half of the study population was of African origin, mainly from Guinea-Bissau. Eleven (34.4%) patients had developed clinical manifestations included within the B or C groups of the CDC classification system for HIV infection, with the rest being asymptomatic. Half of the population was undergoing antiretroviral treatment at the time of the study. HIV-2 subtypes were investigated using a new Nef-based restriction fragment length polymorphism (RFLP) method that allows differentiation of the main two variants, A and B. Plasma viral load was quantified using a new quantitative competitive reverse transcriptase polymerase chain reaction (QcRT-PCR) procedure as well as the Amp-RT assay. Virus isolation was attempted from peripheral blood mononuclear cells. All but one person carried HIV-2 subtype A. Plasma viraemia examined by QcRT-PCR was measurable in 15 (50%) of 30 subjects, yielding in all instances values below 20,000 HIV-2 RNA copies per ml. Plasma RT activity could be detected in only 10 (33%) of 30 subjects, a rate much lower than that seen in HIV-1 infection. Virus was isolated from 16 (53.3%) of 30 patients. A significant correlation was found between CD4+ counts, clinical status, rate of virus isolation, and plasma viral load by both QcRT-PCR and Amp-RT. In conclusion, HIV-2 subtype A is the predominant variant circulating in Portugal among both natives and immigrants. A lower cellular and plasma viral load with respect to HIV-1 was seen in persons without immunosuppression, from whom the rate of virus recovery was extremely low.


Assuntos
HIV-2/isolamento & purificação , Feminino , Produtos do Gene nef/análise , HIV-2/classificação , HIV-2/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Portugal , Estudos Prospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sorotipagem , Carga Viral , Produtos do Gene nef do Vírus da Imunodeficiência Humana
18.
J Clin Microbiol ; 38(4): 1370-4, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10747109

RESUMO

The reverse transcriptase (RT) and protease genes from 12 human immunodeficiency virus type 2 (HIV-2)-infected individuals who had been exposed to antiretroviral drugs for longer than 6 months were examined for the presence of mutations which could be involved in drug resistance. Four individuals carried virus genotypes with amino acid substitutions potentially associated with resistance to nucleoside analogues: two at codon 70 (K-->R) and two at codon 184 (M-->V). Moreover, the latter two patients harbored a codon Q151M mutation which is associated to multidrug resistance in HIV-1, and one of these subjects carried some of the typically linked mutations at codons 65 and 69. With regard to the protease inhibitors, substitutions associated with resistance to protease inhibitors at codon 46 were observed in all individuals. Moreover, minor resistance mutations, as well as new ones of unknown meaning, were often seen in the protease gene. In conclusion, amino acid changes in the HIV-2 RT and protease genes which could be associated with drug resistance seem to occur at positions identical to those for HIV-1.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-2/efeitos dos fármacos , HIV-2/genética , Adolescente , Adulto , Substituição de Aminoácidos , Fármacos Anti-HIV/farmacologia , Resistência Microbiana a Medicamentos/genética , Feminino , Infecções por HIV/virologia , Protease de HIV/genética , Transcriptase Reversa do HIV , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , DNA Polimerase Dirigida por RNA/genética , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/uso terapêutico , Análise de Sequência de DNA
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