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1.
J Virol ; 96(19): e0081122, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36154612

RESUMO

Although many HIV-1-specific CD8+ T cell epitopes have been identified and used in various HIV-1 studies, most of these epitopes were derived from HIV-1 subtypes B and C. Only 17 well-defined epitopes, none of which were protective, have been identified for subtype A/E infection. The roles of HIV-1-specific T cells have been rarely analyzed for subtype A/E infection. In this study, we identified six novel HLA-B*15:02-restricted optimal HIV-1 subtype A/E epitopes and then analyzed the presentation of these epitopes by HIV-1 subtype A/E virus-infected cells and the T cell responses to these epitopes in treatment-naive HIV-1 subtype A/E-infected HLA-B*15:02+ Vietnamese individuals. Responders to the PolTY9 or PolLF10 epitope had a significantly lower plasma viral load (pVL) than nonresponders among HLA-B*15:02+ individuals, whereas no significant difference in pVL was found between responders to four other epitopes and nonresponders. The breadth of T cell responses to these two Pol epitopes correlated inversely with pVL. These findings suggest that HLA-B*15:02-restricted T cells specific for PolTY9 and PolLF10 contribute to the suppression of HIV-1 replication in HLA-B*15:02+ individuals. The HLA-B*15:02-associated mutation Pol266I reduced the recognition of PolTY9-specific T cells in vitro but did not affect HIV-1 replication by PolTY9-specific T cells in Pol266I mutant virus-infected individuals. These findings indicate that PolTY9-specific T cells suppress replication of the Pol266I mutant virus even though the T cells selected this mutant. This study demonstrates the effective role of T cells specific for these Pol epitopes to control circulating viruses in HIV-1 subtype A/E infection. IMPORTANCE It is expected that HIV-1-specific CD8+ T cells that effectively suppress HIV-1 replication will contribute to HIV-1 vaccine development and therapy to achieve an HIV cure. T cells specific for protective epitopes were identified in HIV-1 subtype B and C infections but not in subtype A/E infection, which is epidemic in Southeast Asia. In the present study, we identified six T cell epitopes derived from the subtype A/E virus and demonstrated that T cells specific for two Pol epitopes effectively suppressed HIV-1 replication in treatment-naive Vietnamese individuals infected with HIV-1 subtype A/E. One of these Pol protective epitopes was conserved among circulating viruses, and one escape mutation was accumulated in the other epitope. This mutation did not critically affect HIV-1 control by specific T cells in HIV-1 subtype A/E-infected individuals. This study identified two protective Pol epitopes and characterized them in cases of HIV-1 subtype A/E infection.


Assuntos
Linfócitos T CD8-Positivos , Epitopos de Linfócito T , Infecções por HIV , HIV-1 , Replicação Viral , Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Antígenos HLA-B/imunologia , Humanos , Linfócitos T Citotóxicos/imunologia , Produtos do Gene pol do Vírus da Imunodeficiência Humana/imunologia
2.
J Virol ; 95(6)2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33361435

RESUMO

The Gag280 mutation is associated with HLA-C*01:02 but not with HLA-B*52:01 in subtype A/E-infected individuals, whereas this mutation is associated with HLA-B*52:01 but not with HLA-C*01:02 in subtype B infections. Although it is known that the Gag280 mutant is selected by HLA-B*52:01-restricted GagRI8 (Gag275-282)-specific T cells in subtype B infections, it remains unknown why this Gag280 mutation is associated with HLA-C*01:02 rather than HLA-B*52:01 in subtype A/E infections. The subtype B and A/E viruses have different consensus sequence, with Thr and Val at Gag280, respectively. To clarify the effect of this difference in Gag280 consensus sequence, we investigated the role of HLA-C*01:02-restricted GagYI9 (Gag277-285)-specific T cells in selection of Gag280 mutations in subtype A/E-infected Vietnamese and subtype B-infected Japanese individuals. GagYI9-4V-specific T cells, which were frequently elicited in Vietnamese individuals infected with the consensus-type A/E virus, failed to recognize GagV280T mutant A/E virus-infected cells. GagYI9-4T mutant epitope-specific T cells, which were weakly elicited in individuals infected with the mutant A/E virus, had weak or no ability to recognize the mutant virus. These results account for the mechanism for selection and accumulation of GagV280T mutants in the case of subtype A/E infections. In contrast, HLA-C*01:02-restricted GagYI9-4T-specific T cells were weakly elicited in Japanese individuals infected with the subtype B virus, explaining why HLA-C*01:02-restricted Gag280 mutations are not accumulated in the case of a subtype B infection. The present study demonstrated that a difference in the Gag280 consensus sequence influenced the elicitation of the GagYI9-specific T cells involved in the accumulation of HLA-C*01:02-associated Gag280 mutations.IMPORTANCE HIV-1 mutations escaped from HIV-specific CD8+ T cells are mostly detected as HLA-associated mutations. A diversity of HLA-associated mutations is somewhat distinct to each race and region, since HLA allele distribution differs among them. A difference in the consensus sequence among HIV-1 subtypes may also influence the diversity of HLA-associated mutations. HLA-C*01:02-associated GagV280T and HLA-B*52:01-associated GagT280A/S mutations were previously identified in HIV-1 subtype A/E-infected and subtype B-infected individuals, respectively, though these subtype viruses have a different consensus sequence at Gag280. We demonstrated that the GagV280T mutant virus was selected by HLA-C*01:02-restricted GagYI9-4V-specific T cells in subtype A/E-infected Vietnamese but that HLA-C*01:02-restricted GagYI9-4T-specific T cells were weakly elicited in subtype B-infected Japanese. Together with our recent study which demonstrated the mechanism for the accumulation of HLA-B*52:01-associated mutations, we clarified the mechanism for the accumulation of different Gag280 mutations and the effect of the difference in the consensus sequence on the accumulation of escape mutations.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Genes gag/genética , Infecções por HIV/imunologia , HIV-1/genética , Evasão da Resposta Imune/genética , Povo Asiático , Sequência Consenso , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Antígenos HLA-B/genética , Antígenos HLA-B/imunologia , Antígenos HLA-C/genética , Antígenos HLA-C/imunologia , Humanos , Mutação , Linfócitos T Citotóxicos/imunologia , Replicação Viral
3.
J Virol ; 94(12)2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32295903

RESUMO

Cell entry by HIV-1 is mediated by its principal receptor, CD4, and a coreceptor, either CCR5 or CXCR4, with viral envelope glycoprotein gp120. Generally, CCR5-using HIV-1 variants, called R5, predominate over most of the course of infection, while CXCR4-using HIV-1 variants (variants that utilize both CCR5 and CXCR4 [R5X4, or dual] or CXCR4 alone [X4]) emerge at late-stage infection in half of HIV-1-infected individuals and are associated with disease progression. Although X4 variants also appear during acute-phase infection in some cases, these variants apparently fall to undetectable levels thereafter. In this study, replication-competent X4 variants were isolated from plasma of drug treatment-naive individuals infected with HIV-1 strain CRF01_AE, which dominantly carries viral RNA (vRNA) of R5 variants. Next-generation sequencing (NGS) confirmed that sequences of X4 variants were indeed present in plasma vRNA from these individuals as a minor population. On the other hand, in one individual with a mixed infection in which X4 variants were dominant, only R5 replication-competent variants were isolated from plasma. These results indicate the existence of replication-competent variants with different coreceptor usage as minor populations.IMPORTANCE The coreceptor switch of HIV-1 from R5 to CXCR4-using variants (R5X4 or X4) has been observed in about half of HIV-1-infected individuals at late-stage infection with loss of CD4 cell count and disease progression. However, the mechanisms that underlie the emergence of CXCR4-using variants at this stage are unclear. In the present study, CXCR4-using X4 variants were isolated from plasma samples of HIV-1-infected individuals that dominantly carried vRNA of R5 variants. The sequences of the X4 variants were detected as a minor population using next-generation sequencing. Taken together, CXCR4-using variants at late-stage infection are likely to emerge when replication-competent CXCR4-using variants are maintained as a minor population during the course of infection. The present study may support the hypothesis that R5-to-X4 switching is mediated by the expansion of preexisting X4 variants in some cases.


Assuntos
Infecções por HIV/imunologia , HIV-1/genética , Receptores CCR5/genética , Receptores CXCR4/genética , Receptores de HIV/imunologia , Adulto , Idoso , Sequência de Aminoácidos , Contagem de Linfócito CD4 , Coinfecção , Progressão da Doença , Feminino , Regulação da Expressão Gênica , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Ligação Proteica , RNA Viral/genética , RNA Viral/imunologia , Receptores CCR5/imunologia , Receptores CXCR4/imunologia , Receptores de HIV/genética , Tropismo Viral/genética , Tropismo Viral/imunologia , Ligação Viral , Internalização do Vírus
4.
Biochem Biophys Res Commun ; 508(1): 46-51, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30470571

RESUMO

HIV-1 CRF01_AE viruses are highly prevalent in Southeast Asia. However, vulnerability sites in Env of CRF01_AE viruses have not been investigated sufficiently. We examined the sensitivity of CRF01_AE viruses from Japan and Vietnam, together with subtype B viruses from Japan, to neutralization and Fc-mediated signaling. Neutralization coverage of broadly neutralizing antibodies (bnAbs), 2G12 and b12, was significantly low against CRF01_AE viruses, compared with subtype B viruses. In contrast, the conventional antibody targeting the CD4 binding site (CD4bs), 49G2, showed better neutralization and Fc-mediated signaling activities against CRF01_AE viruses than subtype B viruses. Fc-mediated signaling activity of anti-CD4 induced (CD4i) antibody, 4E9C, was also detected against CRF01_AE viruses more than subtype B viruses. These results suggest that conventional antibodies against CD4bs and CD4i may play an important role in the control of CRF01_AE viruses.


Assuntos
Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Sítios de Ligação/imunologia , Antígenos CD4/imunologia , Epitopos/imunologia , Anticorpos Anti-HIV/imunologia , HIV-1/genética , Humanos , Testes de Neutralização , Receptores de IgG/imunologia , Transdução de Sinais/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética
5.
J Virol ; 92(5)2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29237835

RESUMO

HIV-1-specific cytotoxic T cells (CTLs) play an important role in the control of HIV-1 subtype B or C infection. However, the role of CTLs in HIV-1 subtype A/E infection still remains unclear. Here we investigated the association of HLA class I alleles with clinical outcomes in treatment-naive Vietnamese infected with subtype A/E virus. We found that HLA-C*12:02 was significantly associated with lower plasma viral loads (pVL) and higher CD4 counts and that the HLA-A*29:01-B*07:05-C*15:05 haplotype was significantly associated with higher pVL and lower CD4 counts than those for individuals without these respective genotypes. Nine Pol and three Nef mutations were associated with at least one HLA allele in the HLA-A*29:01-B*07:05-C*15:05 haplotype, with a strong negative correlation between the number of HLA-associated Pol mutations and CD4 count as well as a positive correlation with pVL for individuals with these HLA alleles. The results suggest that the accumulation of mutations selected by CTLs restricted by these HLA alleles affects HIV control.IMPORTANCE Most previous studies on HLA association with disease progression after HIV-1 infection have been performed on cohorts infected with HIV-1 subtypes B and C, whereas few such population-based studies have been reported for cohorts infected with the Asian subtype A/E virus. In this study, we analyzed the association of HLA class I alleles with clinical outcomes for 536 HIV-1 subtype A/E-infected Vietnamese individuals. We found that HLA-C*12:02 is protective, while the HLA haplotype HLA-A*29:01-B*07:05-C*15:05 is deleterious. The individuals with HIV-1 mutations associated with at least one of the HLA alleles in the deleterious HLA haplotype had higher plasma viral loads and lower CD4 counts than those of individuals without the mutations, suggesting that viral adaptation and escape from HLA-mediated immune control occurred. The present study identifies a protective allele and a deleterious haplotype for HIV-1 subtype A/E infection which are different from those identified for cohorts infected with HIV-1 subtypes B and C.


Assuntos
Genes MHC Classe I/genética , Genes MHC Classe I/imunologia , Aptidão Genética , HIV-1/genética , HIV-1/imunologia , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética , Produtos do Gene pol do Vírus da Imunodeficiência Humana/imunologia , Adulto , Alelos , Povo Asiático , Contagem de Linfócito CD4 , Genótipo , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/patogenicidade , Antígenos HLA-A/genética , Antígenos HLA-A/imunologia , Antígeno HLA-B7/genética , Antígeno HLA-B7/imunologia , Antígenos HLA-C/genética , Antígenos HLA-C/imunologia , Haplótipos/genética , Haplótipos/imunologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Mutação , Vietnã , Carga Viral , Replicação Viral
6.
AIDS Care ; 30(12): 1560-1566, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30021450

RESUMO

Missed clinic visits can lead to poorer treatment outcomes in HIV-infected patients. Suboptimal antiretroviral therapy (ART) adherence has been linked to subsequent missed visits. Knowing the determinants of missed visits in Asian patients will allow for appropriate counselling and intervention strategies to ensure continuous engagement in care. A missed visit was defined as having no assessments within six months. Repeated measures logistic regression was used to analyse factors associated with missed visits. A total of 7100 patients were included from 12 countries in Asia with 2676 (37.7%) having at least one missed visit. Patients with early suboptimal self-reported adherence <95% were more likely to have a missed visit compared to those with adherence ≥95% (OR = 2.55, 95% CI(1.81-3.61)). Other factors associated with having a missed visit were homosexual (OR = 1.45, 95%CI(1.27-1.66)) and other modes of HIV exposure (OR = 1.48, 95%CI(1.27-1.74)) compared to heterosexual exposure; using PI-based (OR = 1.33, 95%CI(1.15-1.53) and other ART combinations (OR = 1.79, 95%CI(1.39-2.32)) compared to NRTI+NNRTI combinations; and being hepatitis C co-infected (OR = 1.27, 95%CI(1.06-1.52)). Patients aged >30 years (31-40 years OR = 0.81, 95%CI(0.73-0.89); 41-50 years OR = 0.73, 95%CI(0.64-0.83); and >50 years OR = 0.77, 95%CI(0.64-0.93)); female sex (OR = 0.81, 95%CI(0.72-0.90)); and being from upper middle (OR = 0.78, 95%CI(0.70-0.80)) or high-income countries (OR = 0.42, 95%CI(0.35-0.51)), were less likely to have missed visits. Almost 40% of our patients had a missed clinic visit. Early ART adherence was an indicator of subsequent clinic visits. Intensive counselling and adherence support should be provided at ART initiation in order to optimise long-term clinic attendance and maximise treatment outcomes.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Adesão à Medicação , Adulto , Assistência Ambulatorial , Instituições de Assistência Ambulatorial/organização & administração , Ásia , Feminino , Humanos , Renda , Masculino , Pessoa de Meia-Idade , Prevenção Secundária , Autorrelato
7.
Proc Natl Acad Sci U S A ; 112(27): E3574-81, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26100894

RESUMO

Klebsiella pneumoniae is now recognized as an urgent threat to human health because of the emergence of multidrug-resistant strains associated with hospital outbreaks and hypervirulent strains associated with severe community-acquired infections. K. pneumoniae is ubiquitous in the environment and can colonize and infect both plants and animals. However, little is known about the population structure of K. pneumoniae, so it is difficult to recognize or understand the emergence of clinically important clones within this highly genetically diverse species. Here we present a detailed genomic framework for K. pneumoniae based on whole-genome sequencing of more than 300 human and animal isolates spanning four continents. Our data provide genome-wide support for the splitting of K. pneumoniae into three distinct species, KpI (K. pneumoniae), KpII (K. quasipneumoniae), and KpIII (K. variicola). Further, for K. pneumoniae (KpI), the entity most frequently associated with human infection, we show the existence of >150 deeply branching lineages including numerous multidrug-resistant or hypervirulent clones. We show K. pneumoniae has a large accessory genome approaching 30,000 protein-coding genes, including a number of virulence functions that are significantly associated with invasive community-acquired disease in humans. In our dataset, antimicrobial resistance genes were common among human carriage isolates and hospital-acquired infections, which generally lacked the genes associated with invasive disease. The convergence of virulence and resistance genes potentially could lead to the emergence of untreatable invasive K. pneumoniae infections; our data provide the whole-genome framework against which to track the emergence of such threats.


Assuntos
Variação Genética , Genoma Bacteriano/genética , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Animais , Anti-Infecciosos/farmacologia , Proteínas de Bactérias/classificação , Proteínas de Bactérias/genética , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Genes Bacterianos/genética , Genômica/métodos , Humanos , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/patogenicidade , Filogenia , Dinâmica Populacional , Saúde Pública/estatística & dados numéricos , Saúde Pública/tendências , Análise de Sequência de DNA , Especificidade da Espécie , Virulência/genética
8.
AIDS Care ; 29(10): 1243-1254, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28132544

RESUMO

The scale-up of antiretroviral therapy (ART) has led to a substantial change in the clinical population of HIV-positive patients receiving care. We describe the temporal trends in the demographic and clinical characteristics of HIV-positive patients initiating ART in 2003-13 within an Asian regional cohort. All HIV-positive adult patients that initiated ART between 2003 and 2013 were included. We summarized ART regimen use, age, CD4 cell count, HIV viral load, and HIV-related laboratory monitoring rates during follow-up by calendar year. A total of 16 962 patients were included in the analysis. Patients in active follow-up increased from 695 patients at four sites in 2003 to 11,137 patients at eight sites in 2013. The proportion of patients receiving their second or third ART regimen increased over time (5% in 2003 to 29% in 2013) along with patients aged ≥50 years (8% in 2003 to 18% in 2013). Concurrently, CD4 monitoring has remained stable in recent years, whereas HIV viral load monitoring, although varied among the sites, is increasing. There have been substantial changes in the clinical and demographic characteristics of HIV-positive patients receiving ART in Asia. HIV programmes will need to anticipate the clinical care needs for their aging populations, expanded viral load monitoring, and, the eventual increase in second and third ART regimens that will lead to higher costs and more complex drug procurement needs.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Avaliação de Processos e Resultados em Cuidados de Saúde/métodos , Avaliação de Programas e Projetos de Saúde/métodos , Carga Viral/efeitos dos fármacos , Adulto , Ásia/epidemiologia , Contagem de Linfócito CD4 , Estudos de Coortes , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde/estatística & dados numéricos , Adulto Jovem
9.
J Virol ; 89(14): 7363-72, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25972553

RESUMO

UNLABELLED: The effect of antiretroviral drug resistance mutations on cytotoxic T lymphocyte (CTL) recognition has been analyzed in HIV-1 subtype B infections, but it remains unclear in infections by other HIV-1 subtypes that are epidemic in countries where antiretroviral drugs are not effectively used. We investigated the effect of nonnucleoside reverse transcriptase (RT) inhibitor (NNRTI)-resistance mutations (Y181C, Y181I, and Y181V) on epitope recognition by CTLs specific for 3 different HIV-1 epitopes (HLA-A*02:01-restricted IV10, HLA-B*35:01-restricted NY9, and HLA-C*12:02-restricted KY9) in subtype B and subtype A/E infections and the accumulation of these mutations in treatment-naive Japanese and Vietnamese. These NNRTI-resistance mutations critically affected NY9-specific and KY9-specific T cell responses in the subtype B infections, whereas they showed a different effect on IV10-specific T cell responses among the subtype B-infected individuals. These mutations affected IV10-specific T cell responses but weakly affected NY9-specific T cell responses in the subtype A/E infections. The substitution at position 3 of NY9 epitope which was found in the subtype A/E virus differently influenced the peptide binding to HLA-B*35:01, suggesting that the differences in peptide binding may result in the differences in T cell recognition between the subtype B virus and A/E virus infections. The Y181C mutation was found to be accumulating in treatment-naive Vietnamese infected with the subtype A/E virus. The present study demonstrated different effects of NNRTI-resistance RT181 mutations on CTL responses between the 2 subtype infections. The Y181C mutation may influence HIV-1 control by the CTLs in Vietnam, since this mutation has been accumulating in treatment-naive Vietnamese. IMPORTANCE: Antiretroviral therapy leads to the emergence of drug-resistant HIV-1, resulting in virological and clinical failures. Though HIV-1-specific CTLs play a critical role in HIV-1 infection, some of drug resistance mutations located in CTL epitopes are known to affect HIV-1-specific CTL responses. Nonnucleoside reverse transcriptase inhibitor (NNRTI)-resistance RT181 mutations are frequently observed in patients treated with NNRTIs. Such drug resistance mutations may have an influence on immune control by HIV-1-specific CTLs, especially in countries where antiretroviral drugs are not effectively used. We here investigated the effect of three NNRTI-resistance RT181 mutations on immune responses by HIV-1-specific CTLs and the recent accumulation of these mutations in treatment-naive Vietnamese infected with HIV-1 subtype A/E virus. RT181 mutations affected CTL recognition in both subtype A/E and B infections, while the RT Y181C mutation has been accumulating in treatment-naive Vietnamese. The results suggest that the Y181C mutation may influence HIV-1 control by CTLs in Vietnam.


Assuntos
Farmacorresistência Viral , Transcriptase Reversa do HIV/genética , Transcriptase Reversa do HIV/imunologia , Mutação de Sentido Incorreto , Nucleosídeos/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Linfócitos T Citotóxicos/imunologia , Epitopos/genética , Epitopos/imunologia , Genótipo , Infecções por HIV/virologia , Transcriptase Reversa do HIV/classificação , Humanos , Japão , Proteínas Mutantes/genética , Proteínas Mutantes/imunologia , Nucleosídeos/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Vietnã
10.
BMC Public Health ; 13: 1158, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24325208

RESUMO

BACKGROUND: Antimicrobial resistance is a major contemporary public health threat. Strategies to contain antimicrobial resistance have been comprehensively set forth, however in developing countries where the need for effective antimicrobials is greatest implementation has proved problematic. A better understanding of patterns and determinants of antibiotic use and resistance in emerging economies may permit more appropriately targeted interventions.Viet Nam, with a large population, high burden of infectious disease and relatively unrestricted access to medication, is an excellent case study of the difficulties faced by emerging economies in controlling antimicrobial resistance. METHODS: Our working group conducted a situation analysis of the current patterns and determinants of antibiotic use and resistance in Viet Nam. International publications and local reports published between 1-1-1990 and 31-8-2012 were reviewed. All stakeholders analyzed the findings at a policy workshop and feasible recommendations were suggested to improve antibiotic use in Viet Nam.Here we report the results of our situation analysis focusing on: the healthcare system, drug regulation and supply; antibiotic resistance and infection control; and agricultural antibiotic use. RESULTS: Market reforms have improved healthcare access in Viet Nam and contributed to better health outcomes. However, increased accessibility has been accompanied by injudicious antibiotic use in hospitals and the community, with predictable escalation in bacterial resistance. Prescribing practices are poor and self-medication is common - often being the most affordable way to access healthcare. Many policies exist to regulate antibiotic use but enforcement is insufficient or lacking.Pneumococcal penicillin-resistance rates are the highest in Asia and carbapenem-resistant bacteria (notably NDM-1) have recently emerged. Hospital acquired infections, predominantly with multi-drug resistant Gram-negative organisms, place additional strain on limited resources. Widespread agricultural antibiotic use further propagates antimicrobial resistance. CONCLUSIONS: Future legislation regarding antibiotic access must alter incentives for purchasers and providers and ensure effective enforcement. The Ministry of Health recently initiated a national action plan and approved a multicenter health improvement project to strengthen national capacity for antimicrobial stewardship in Viet Nam. This analysis provided important input to these initiatives. Our methodologies and findings may be of use to others across the world tackling the growing threat of antibiotic resistance.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Países em Desenvolvimento , Farmacorresistência Bacteriana , Uso de Medicamentos/normas , Política de Saúde , Humanos , Vietnã
11.
AIDS Res Ther ; 9(1): 24, 2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22897817

RESUMO

OBJECTIVE: This study reports the clinical characteristics and outcome of HIV-associated Penicilliummarneffei infection in northern Vietnam. METHODS: We conducted a retrospective chart review of all patients with laboratory confirmed Penicilliummarneffei infection admitted to the National Hospital for Tropical Diseases in Hanoi, Vietnam, between July 2006 and September 2009. RESULTS: 127 patients with P. marneffei infection were identified. All were HIV-infected; median CD4+ T-cell count was 24 cells/µl (IQR:12-48); 76% were men. Common clinical features were fever (92.9%), skin lesions (82.6%), hepatomegaly (61.4%), lymphadenopathy (40.2%), weight loss (59.1%) and cough (49.6%). Concurrent opportunistic infections were present in 22.0%; half of those had tuberculosis. Initial treatment regimens were: itraconazole or ketoconazole capsule (77.2%), amphotericin B (20.5%), and fluconazole (1.6%). In-hospital mortality was 12.6% and showed no significant difference in patients treated with itraconazole (or ketoconazole) and amphotericin B (p = 0.43). Dyspnea, ascites, and increased LDH level were independent predictors of mortality. No seasonality was observed. CONCLUSION: The clinical features, treatments and outcomes of HIV-associated P. marneffei infection in northern Vietnam are similar to those reported in other endemic regions. Dyspnea was an important predictor of mortality. More patients were treated with itraconazole than amphotericin B and no significant difference in treatment outcome was observed. It would be of clinical value to compare the efficacy of oral itraconazole and amphotericin B in a clinical trial.

12.
Glob Health Med ; 4(3): 146-151, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35855066

RESUMO

There is little evidence regarding the association between hepatitis B virus (HBV) chronicity and HLA-DP among the HIV-infected Vietnamese population. To study this, we conducted a cross-sectional analysis and a prospective study involving an HIV-infected Vietnamese cohort. The association between HBV chronicity and HLA-DP single nucleotide polymorphisms (SNPs) of rs3077 and rs9277535 among Vietnamese patients with previous HBV exposure was first evaluated. In addition, treatment-naive patients with chronic HBV infection were followed between 2012 and 2017 for HBV clearance after the initiation of antiretroviral therapy (ART). A total of 820 subjects with previous HBV exposure were included in the cross-sectional study. Among them, 147 (17.9 %) had chronic HBV infection, and 673 (82.1 %) achieved HBV clearance. The proportions of minor allele homozygotes of rs3077 and rs9277535 were 10.9 % and 15.2 % (p = 0.481) and 4.1 % and 11.7 % (p = 0.003), respectively. Multivariate analysis showed that rs9277535 minor homozygote was a significant protective factor against chronic HBV infection (odds ratio [OR], 0.271; 95 % confidence interval [CI]; 0.114-0.642, p = 0.001). Further, none of the 43 patients in the prospective study, who received ART possessed the rs9277535 minor homozygote. The average follow-up period was 4.8 years, and 10 subjects (23.3 %, 4.9 %/person-years) achieved HBV clearance. Univariate analysis revealed that the SNPs were not significantly associated with HBV clearance. In conclusion, our study confirmed that the rs9277535 minor allele homozygote was significantly associated with HBV clearance among HIV-infected Vietnamese patients.

13.
BMJ Open ; 12(12): e062745, 2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36576192

RESUMO

OBJECTIVES: Given limited data on factors associated with hepatitis C virus (HCV) treatment discontinuation and failure in low- and middle-income countries, we aimed to describe patient populations treated for HCV in five countries and identify patient groups that may need additional support. DESIGN: Retrospective cohort analysis using routinely collected data. SETTING: Public sector HCV treatment programmes in India (Punjab), Indonesia, Myanmar, Nigeria (Nasarawa) and Vietnam. PARTICIPANTS: 104 957 patients who initiated treatment in 2016-2022 (89% from Punjab). PRIMARY OUTCOMES: Treatment completion and cure. RESULTS: Patient characteristics and factors associated with outcomes varied across countries and facilities. Across all patients, median age was 40 years (IQR: 29-52), 30.6% were female, 7.0% reported a history of injecting drugs, 18.2% were cirrhotic and 4.9% were coinfected with HIV. 79.8% were prescribed sofosbuvir+daclastasvir. Of patients with adequate follow-up, 90.6% (89,551) completed treatment. 77.5% (69,426) of those who completed treatment also completed sustained virological testing at 12 weeks (SVR12), and of those, 92.6% (64 305) were cured. In multivariable-adjusted models, in most countries, significantly lower treatment completion was observed among patients on 24-week regimens (vs 12-week regimens) and those initiated in later years of the programme. In several countries, males, younger patients <20 years and certain groups of cirrhotic patients were less likely to complete treatment or be cured. In Punjab, treatment completion was also lower in those with a family history of HCV and people who inject drugs (PWID); in other countries, outcomes were comparable for PWID. CONCLUSION: High proportions of patients completed treatment and were cured across patient groups and countries. SVR12 follow-up could be strengthened. Males, younger people and those with decompensated cirrhosis on longer regimens may require additional support to complete treatment and achieve cure. Adequate programme financing, minimal user fees and implementation of evidence-based policies will be critical to close gaps.


Assuntos
Hepatite C Crônica , Hepatite C , Abuso de Substâncias por Via Intravenosa , Masculino , Humanos , Feminino , Adulto , Hepacivirus , Antivirais/uso terapêutico , Estudos Retrospectivos , Hepatite C Crônica/tratamento farmacológico , Abuso de Substâncias por Via Intravenosa/complicações , Países em Desenvolvimento , Setor Público , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C/complicações , Estudos de Coortes , Cirrose Hepática/complicações
14.
PLoS One ; 16(4): e0250828, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33914827

RESUMO

Tenofovir disoproxil fumarate (TDF) is still widely prescribed for human immunodeficiency virus (HIV)-infected pregnant women, despite its renal and bone toxicity. Although TDF-exposed infants often show transient growth impairment, it is not clear whether maternal TDF causes infantile rickets via maternal/fetal renal dysfunction in Asian populations. This prospective observational study was conducted in Vietnam and involved pregnant HIV-infected women treated with TDF-based regimen (TDF group) or zidovudine-based regimen (AZT-group). At birth, 3, 12, and 18 months of age, and included body length, weight, head circumference, serum alkaline phosphatase (ALP), creatinine, calcium, phosphorus, urine-ß2-microglobulin (U-BMG), percentage of tubular reabsorption of phosphate (%TRP), and radiographic wrist score for rickets. Age-adjusted multivariate linear regression analysis evaluated the association of TDF/AZT use during pregnancy with fetal renal function and bone health. The study included 63 mother-infant pairs (TDF group = 53, AZT group = 10). In the mothers, detectable U-BMG (>252 µg/L) was observed more frequently in the TDF- than AZT group (89 vs 50%, p<0.001), but other renal/bone parameters were similar. In infants, maternal TDF use was not associated with growth impairment, renal dysfunction, or abnormal bone findings, but with a slightly higher ALP levels (p = 0.019). However, shorter length was associated with maternal AZT (p = 0.021), and worse radiographic scores were associated with LPV/r (p = 0.024). In Vietnamese population, TDF usage during pregnancy was not associated with infant transient rickets, growth impairment, or renal dysfunction, despite mild maternal tubular impairment. Maternal AZT and LPV/r influenced infant growth and bone health, though further studies are needed to confirm this finding.


Assuntos
Infecções por HIV/tratamento farmacológico , Exposição Materna/efeitos adversos , Tenofovir/efeitos adversos , Zidovudina/efeitos adversos , Microglobulina beta-2/urina , Estatura/efeitos dos fármacos , Endopeptidases/sangue , Feminino , Humanos , Lactente , Masculino , Análise Multivariada , Gravidez , Gestantes , Estudos Prospectivos , Tenofovir/uso terapêutico , Vietnã , Zidovudina/uso terapêutico
15.
Glob Health Med ; 2(6): 374-383, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33409417

RESUMO

The Brief Coping Orientation to Problem Experienced (Brief COPE) inventory is one of the most widely used instruments in coping research; however, no study has evaluated the psychometric properties of the Brief COPE in the Vietnamese population. This study aimed to validate a culturally appropriate Vietnamese version of the Brief COPE for the evaluation of coping strategies in people living with HIV/AIDS in Vietnam. We translated the Brief COPE into Vietnamese, and it was self-administered among 1,164 HIV-infected patients receiving antiretroviral therapy at a large HIV outpatient clinic in Hanoi between January 2019 and March 2020. Data on demographics and HIV-related information, depression and social support were also collected. Confirmatory factor analysis (CFA) and exploratory factor analysis (EFA) were conducted to assess construct validity. Content validity, internal consistency, and convergent validity were also assessed. The CFA of a 14-factor structure of the original Brief COPE revealed acceptable model fitness, but poor internal consistency for some subscales. In the subsequent EFA, we found a revised 26-item version which had a six-factor structure consisting of problem-solving, avoidance, humor, social support, religion, and substance use. The final CFA found that the model fitness of the revised scale with fewer factor structures was comparable to that of the original Brief COPE; the internal consistency of the revised scale was even better than that of the original scale. Furthermore, six factors of the revised scale showed anticipated associations with depression and social support.

16.
Clin Infect Dis ; 49(7): e79-83, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19712034

RESUMO

Trichinellosis outbreaks occur occasionally in Vietnam following the consumption of undercooked pork. Diagnosing trichinella can be problematic because fever and myalgia are nonspecific, and diagnosis may be delayed. We describe 5 Vietnamese patients in whom trichinellosis was diagnosed after several weeks of illness.


Assuntos
Doenças Transmitidas por Alimentos/parasitologia , Trichinella/isolamento & purificação , Triquinelose/diagnóstico , Adolescente , Adulto , Animais , Febre/etiologia , Humanos , Masculino , Músculo Estriado/patologia , Dor , Triquinelose/patologia , Triquinelose/fisiopatologia , Vietnã , Adulto Jovem
17.
J Int AIDS Soc ; 22(3): e25264, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30924281

RESUMO

INTRODUCTION: Cotrimoxazole (CTX) is recommended as prophylaxis against Pneumocystis jiroveci pneumonia, malaria and other serious bacterial infections in HIV-infected patients. Despite its in vitro activity against Mycobacterium tuberculosis, the effects of CTX preventive therapy on tuberculosis (TB) remain unclear. METHODS: Adults living with HIV enrolled in a regional observational cohort in Asia who had initiated combination antiretroviral therapy (cART) were included in the analysis. Factors associated with new TB diagnoses after cohort entry and survival after cART initiation were analysed using Cox regression, stratified by site. RESULTS: A total of 7355 patients from 12 countries enrolled into the cohort between 2003 and 2016 were included in the study. There were 368 reported cases of TB after cohort entry with an incidence rate of 0.99 per 100 person-years (/100 pys). Multivariate analyses adjusted for viral load (VL), CD4 count, body mass index (BMI) and cART duration showed that CTX reduced the hazard for new TB infection by 28% (HR 0.72, 95% CI l 0.56, 0.93). Mortality after cART initiation was 0.85/100 pys, with a median follow-up time of 4.63 years. Predictors of survival included age, female sex, hepatitis C co-infection, TB diagnosis, HIV VL, CD4 count and BMI. CONCLUSIONS: CTX was associated with a reduction in the hazard for new TB infection but did not impact survival in our Asian cohort. The potential preventive effect of CTX against TB during periods of severe immunosuppression should be further explored.


Assuntos
Infecções por HIV/complicações , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Tuberculose/prevenção & controle , Adulto , Fármacos Anti-HIV/uso terapêutico , Antirretrovirais/uso terapêutico , Ásia/epidemiologia , Estudos de Coortes , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Tuberculose/epidemiologia , Tuberculose/etiologia , Tuberculose/mortalidade , Carga Viral
19.
Infect Drug Resist ; 11: 275-282, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29535543

RESUMO

INTRODUCTION: Pseudomonas aeruginosa has many mechanisms of resistance to fluoroquinolones. The main mechanism is to change the effect of two enzymes that open the DNA helix - the enzyme DNA gyrase (gyrA) and the topoisomerase IV (parC). In addition, mutations that render the MexAB-oprM pump (mexR) dysfunctional, leading to its overexpression, also enhance resistance to fluoroquinolones. In this study, we aim to detect point mutations of gyrA, parC, and mexR genes that are predicted to be associated with fluoroquinolone resistance in 141 fluoroquinolone-resistant clinical isolates of P. aeruginosa isolated in Vietnam during 2013-2016. METHODS: We tested minimum inhibitory concentrations (MICs) of fluoroquinolone antibiotics in 141 clinical isolates of P. aeruginosa using the VITEK 2 Compact System, followed by PCR assay, to detect and clone the fluoroquinolone resistance-determining region (FRDR) of gyrA, parC, and mexR. Point mutations were analyzed through Sanger sequencing, and the correlation between genetic mutations and phenotypic resistance of 141 clinical isolates was undertaken. RESULTS: Fluoroquinolone-resistant substitution mutations such as Ile for Thr83 and Met for Thr133 in gyrA, Leu for Ser87 in parC, and Val for Glu126 in the repressor of mexR were mainly detected. Comparative analytical data indicated that amino acid alterations within the gyrA and parC genes are highly associated with resistance to ciprofloxacin (CIP) and levofloxacin (LEV) in the isolates, whereas alterations in the efflux regulatory mexR gene are not highly consistent with resistance in these isolates. Moreover, fluoroquinolone-resistant clinical isolates of P. aeruginosa were mainly isolated from pus and sputum specimens. CONCLUSION: In clinical isolates of P. aeruginosa, a high correlation was observed between MICs of CIP and LEV and alterations in gyrA and parC genes. However, mutations occurring in mexR did not highly correlate with the antibiotic resistance of the bacterium.

20.
Sci Rep ; 7(1): 15489, 2017 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-29138432

RESUMO

Depression is the most common mental health issue among people living with HIV/AIDS (PLWHA). This study explored how different types and sources of social support are associated with depression among HIV-infected patients in Vietnam. We carried out a cross-sectional survey on 1,503 HIV-infected patients receiving antiretroviral therapy at two HIV clinics in Hanoi in 2016. Depression was prevalent in 26.2% of participants. Higher score of social support, especially emotional/informational support and positive social interaction, showed significant association with lower depression rate. Although family was primary source of all types of social support, receiving emotional/informational support not only from family but also from outside of family correlated with a lower proportion of depression. In countries with constrained social resources and/or with family-oriented social structures, as in Vietnam, expanding social networks between HIV populations and society is a potentially important option for reducing depression.


Assuntos
Depressão/prevenção & controle , Infecções por HIV/psicologia , Rede Social , Apoio Social , Adulto , Instituições de Assistência Ambulatorial , Fármacos Anti-HIV/uso terapêutico , Estudos de Coortes , Estudos Transversais , Depressão/epidemiologia , Depressão/psicologia , Família/psicologia , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Projetos Piloto , Prevalência , Qualidade de Vida , Autorrelato/estatística & dados numéricos , Vietnã/epidemiologia
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