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1.
Antiviral Res ; 92(2): 382-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21920388

RESUMO

Presence of drug-resistance mutations in drug-naïve hepatitis B virus (HBV) infected patients can seriously compromise response to antiviral treatment. Therefore, our study was aimed at defining the prevalence of HBV drug-resistance in a population of 140 patients, all infected with HBV-D-genotype (the most common HBV-genotype in Eastern Europe, Mediterranean countries and Middle East) and naïve to antiviral therapy. HBV reverse-transcriptase (RT) region was sequenced and analyzed for 20 mutations, confirmed by in vitro studies as associated with resistance to nucleos(t)ide HBV-RT inhibitors (rtL80I/V-rtI169T-rtV173L-rtL180M-rtA181T/V/S-rtT184A/S/G/C-rtA194T-rtS202C/G/I-rtM204V/I-rtN236T-rtM250V). Amino acid changes at other six RT positions, potentially associated with resistance, were also analyzed (rtV84M-rtV191I-rtV207L-rtV214A-rtQ215S-rtI233V). Overall, only 2/140 (1.4%) patients carried primary drug-resistance mutations [rtA181V (0.7%), and rtA194T (0.7%)], while 3/140 (2.1%) patients harbored the secondary mutations rtV173L (1.4%) and rtL180M (0.7%). Additionally, five polymorphic mutations, with a suggested role in drug resistance, were detected [rtQ215S (12.8%), rtI233V (4.3%), rtV214A (3.6%), rtV191I (0.7%), rtV207L (0.7%)]. Notably, no YMDD mutations, namely rtM204V/I, were found. Taken together, the rate of important drug resistance mutations in naïve HBV D-genotype infected patients is today very low, and suggests the potential full efficacy of new-generation antiviral drugs used in first line therapy. Whether such low rate can be extrapolated to non HBV-D subtypes, requires a detailed investigation to be performed in a different cohort of patients.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Mutação de Sentido Incorreto , Adulto , Substituição de Aminoácidos , Análise Mutacional de DNA , DNA Viral/química , DNA Viral/genética , Europa Oriental , Genótipo , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Humanos , Região do Mediterrâneo , Pessoa de Meia-Idade , Oriente Médio , Dados de Sequência Molecular , Prevalência , DNA Polimerase Dirigida por RNA/genética , Análise de Sequência de DNA , Proteínas Virais/genética
2.
Int J STD AIDS ; 14(6): 417-25, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12816671

RESUMO

As part of an extensive multi-institutional DIANAIDS study focused on assessing the risk factors, natural history, diagnosis and follow-up of genital human papillomavirus (HPV) infections in HIV-infected women, the present communication reports a sub-cohort of 142 women (89 HIV+ and 48 HIV-), followed-up for a mean of 14.07 (+/-10.84) months to analyse the factors predicting the persistence and clearance of HPV infections (polymerase chain reaction [PCR] and sequencing) and cervical Papanicolaou (PAP) smear abnormalities, using both univariate (Kaplan-Meier) and multivariate (Cox) survival analysis. The appearance of new HPV infections during the follow-up was significantly more frequent in HIV-positive than in HIV-negative women, odds ratio (OR) 8.800 (95% confidence interval [CI]: 1.199-64.611), and also the clearance rate was significantly less frequent in HIV-positive than in HIV-negative women, 69.2% vs 22.8%, respectively (OR 0.330; 95% CI: 0.163-0.670). These two groups were also markedly different with respect to the clinical course of the cervical lesions, in the frequency of progressive disease (determined by PAP smear) was higher in HIV-positive group (12/89) than in HIV-negative women (2/52) (OR 3.506; 95% CI 0.816-15.055) (P = 0.055), in whom the disease regressed more frequently than in HIV-positive women (13.5% vs 7.9%) (OR 0.584; 95% CI 0.217-1.573). Using (1) HPV-positivity, (2) oncogenic HPV-type and (3) significant PAP smear abnormality at the end of follow-up as outcome measures, (1) was significantly (P < 0.001) predicted by the following variables in univariate analysis: age, mode of contraception, CD4 count, and HIV-positivity. The significant predictors of (2) were age and mode of contraception. The outcome measure (3) was significantly predicted by CD4 count, PAP smear abnormality and PCR status at entry. In the multivariate analysis, the significant independent predictive factors for HPV-positivity proved to be only the HIV status (P < 0.001), and PCR status at entry, p53 polymorphism at aa-72, oncogenic HPV type and significant PAP smear at entry remained independent predictors, with the significance level of P < 0.05. None of the significant predictors of oncogenic HPV type in univariate analysis retained their independent value in multivariate analysis. Oncogenic HPV type at entry proved to be an independent predictor of significant PAP smear (P < 0.05). The present results indicate that HIV-infected women, even on highly active antiretroviral therapy, demonstrate a more aggressive clinical course of cervical HPV infections, and fail to eradicate the disease more frequently than HIV-negative women. This persistence of HPV-positivity, oncogenic HPV type and significant PAP smear abnormality can be predicted by the results of PAP test and HPV typing in univariate analyses, and partly retain their independent predictive value also in multivariate analysis. Clearly, in addition to regular monitoring by PAP smear, HPV testing for the oncogenic HPV types seems to provide additional prognostic information in the management of cervical lesions in HIV-infected women.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/patologia , Infecções Oportunistas Relacionadas com a AIDS/virologia , Teste de Papanicolaou , Papillomaviridae , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Infecções Tumorais por Vírus/patologia , Infecções Tumorais por Vírus/virologia , Doenças do Colo do Útero/patologia , Doenças do Colo do Útero/virologia , Esfregaço Vaginal , Adolescente , Adulto , Fatores Etários , Análise de Variância , Anticoncepção/efeitos adversos , Anticoncepção/métodos , DNA Viral/análise , DNA Viral/genética , Progressão da Doença , Feminino , Seguimentos , Soronegatividade para HIV , Humanos , Itália , Pessoa de Meia-Idade , Papillomaviridae/classificação , Papillomaviridae/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Risco , Análise de Sobrevida , Esfregaço Vaginal/normas
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