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1.
J Viral Hepat ; 21(7): 458-65, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24750327

RESUMO

Hepatitis C virus (HCV) vaccines may be able to increase viral clearance in combination with antiviral therapy. We analysed viral dynamics and HCV-specific immune response during retreatment for experienced patients in a phase Ib study with E1E2MF59 vaccine. Seventy-eight genotype 1a/1b patients [relapsers (30), partial responders (16) and nonresponders (32) to interferon-(IFN)/ribavirin-(RBV)] were randomly assigned to vaccine (V:23), Peg-IFNα2a-180-ug/qw and ribavirin 1000-1200-mg/qd for 48 weeks (P/R:25), or their combination (P/R + V:30). Vaccine (100 µg/0.5 mL) was administered intramuscularly at week 0-4-8-12-24-28-32-36. Neutralizing of binding (NOB) antibodies and lymphocyte proliferation assay (LPA) for E1E2-specific-CD4 + T cells were performed at week 0-12-16-48. Viral kinetics were analysed up to week 16. The vaccine was safe, and a sustained virological response (SVR) was achieved in 4 P/R + V and 2 P/R patients. Higher SVR rates were observed in prior relapsers (P/R + V = 27.3%; P/R = 12.5%). Higher NOB titres and LPA indexes were found at week 12 and 16 in P/R + V as compared to P/R patients (P = 0.023 and 0.025, P = 0.019 and <0.001, respectively). Among the 22 patients with the strongest direct antiviral effects of IFN (ε ≥ 0.800), those treated with P/R + V (10) reached lower HCV-RNA levels (P = 0.026) at week 16. HCV E1E2MF59 vaccine in combination with Peg-IFNα2a + RBV was safe and elicited E1E2 neutralizing antibodies and specific CD4 + T cell proliferation. Upon early response to IFN, vaccinations were associated with an enhanced second phase viral load decline. These results prompt phase II trials in combination with new antiviral therapies.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Antivirais/uso terapêutico , Hepatite C Crônica/terapia , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Polissorbatos/administração & dosagem , Ribavirina/uso terapêutico , Esqualeno/administração & dosagem , Vacinas contra Hepatite Viral/imunologia , Adjuvantes Imunológicos/efeitos adversos , Anticorpos Neutralizantes/sangue , Linfócitos T CD4-Positivos/imunologia , Proliferação de Células , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Anticorpos Anti-Hepatite C/sangue , Humanos , Injeções Intramusculares , Polissorbatos/efeitos adversos , RNA Viral/sangue , Proteínas Recombinantes/uso terapêutico , Esqualeno/efeitos adversos , Resultado do Tratamento , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/efeitos adversos , Vacinas contra Hepatite Viral/genética , Carga Viral
3.
Clin Pharmacol Ther ; 84(2): 212-5, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18388885

RESUMO

A novel biomathematical model that analyzes the combined alanine transaminase (ALT) and viral-load kinetics during the first month of pegylated interferon (Peg-IFN) plus ribavirin (RBV) therapy was successfully applied in 90 of 97 (93%) chronic hepatitis C patients in order to compute the number of infected cells at the end of therapy (I(eot)). The I(eot) indices were lower in sustained virological responders than in relapsers (RELs) and nonresponders (NRs) (median values: 31 vs. 2,190 vs. 1,090,000; P < 0.001), and were independently associated with treatment outcomes (P = 0.003). A threshold of 250 I(eot) was shown to identify sustained virological response (SVR) with high positive predictive value (93%) and good diagnostic accuracy (81%). The time taken to attain 250 I(eot) ranged from 3 to 11 months in patients with hepatitis C virus (HCV) genotypes 2 or 3 and from 3 to 18 months in those with HCV genotypes 1 or 4. Overall, the duration of therapy would have been 49 months less than that suggested by the most recent algorithms based on a rapid virological response (RVR) at week 4.


Assuntos
Alanina Transaminase/sangue , Antivirais/uso terapêutico , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Interleucina-2/análogos & derivados , Ribavirina/uso terapêutico , Carga Viral , Adulto , Antivirais/administração & dosagem , Biomarcadores/sangue , Portadores de Fármacos , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/enzimologia , Humanos , Interleucina-2/administração & dosagem , Interleucina-2/uso terapêutico , Cinética , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Modelos Teóricos , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/uso terapêutico , Valor Preditivo dos Testes , RNA Viral/isolamento & purificação , Curva ROC , Ribavirina/administração & dosagem , Resultado do Tratamento
4.
J Viral Hepat ; 14(5): 360-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17439526

RESUMO

Liver stiffness was measured by transient elastography (FibroScan) in 228 consecutive patients with chronic viral hepatitis, with (115) or without cirrhosis (113), to study its correlations with serum transaminases [alanine aminotransferase (ALT)], fibrosis stage and surrogate noninvasive markers of fibrosis (APRI, FORNS, FibroTest and hyaluronic acid). The dynamic profiles of serum transaminases and liver stiffness were compared by multiple testing in 31 patients during a 6-month follow-up. We identified 8.3 and 14 kPa as the fibrosis >/=F2 and cirrhosis cut-offs, respectively: their sensitivities were 85.2%/78.3%; specificities 90.7%/98.2%; positive predictive values 93.9%/97.8%; negative predictive values 78.8%/81.6%; diagnostic accuracies 87.3%/88.2%. FibroScan performed better than the other surrogate markers of fibrosis (P < 0.001). Other than fibrosis, other factors independently associated with liver stiffness were ALT for all patients and chronic hepatitis patients (P < 0.001), and 12-month persistently normal ALT (biochemical remission, P < 0.001) in cirrhotics. In patients with biochemical remission either spontaneous or after antiviral therapy (48 of 228, 21%), liver stiffness was lower than in patients with identical fibrosis stage, but elevated ALT (P < 0.001). The liver stiffness dynamic profiles paralleled those of ALT, increasing 1.3- to 3-fold during ALT flares in 10 patients with hepatitis exacerbations. Liver stiffness remained unchanged in 21 with stable biochemical activity (P = 0.001). In conclusion, transient elastography is a new liver parameter that behaves as a reliable surrogate marker of fibrosis in chronic viral hepatitis patients, provided that its relationship with major changes of biochemical activity is taken into account.


Assuntos
Alanina Transaminase/sangue , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Cirrose Hepática/patologia , Adulto , Idoso , Biomarcadores/sangue , Biópsia , Elasticidade , Feminino , Seguimentos , Humanos , Fígado/cirurgia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Sensibilidade e Especificidade , Fatores de Tempo
5.
J Antimicrob Chemother ; 60(2): 341-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17567633

RESUMO

OBJECTIVES: We studied the impact of hepatitis B virus (HBV) polymerase/reverse transcriptase (Pol/Rt) heterogeneity on adefovir rescue therapy in 34 consecutive chronic hepatitis B patients with viral breakthrough during lamivudine monotherapy. METHODS: The Pol/Rt A-F domains were directly sequenced in all patients at baseline, and 12 and 24 months. Response to therapy was evaluated at 3, 6, 12 and 24 months by quantitative HBV-DNA. RESULTS: Primary treatment failures did not occur. At 6 months 24/34 (70.6%) patients had viraemia<10(4) copies/mL [initial viral response (IVR)]; at 12 and 24 months 23 (71.9%) and 26 (81.3%) of 32 had HBV-DNA<200 copies/mL [complete viral response (CVR)]. IVR or CVR patients did not show viral breakthroughs, which occurred in one of the six remaining patients. All but three patients had baseline rtM204I/V substitutions associated with rtL180M in 23, rtL80I/V in 14, rtV173L in 4, rtT184S in 3, rtQ215S in 2 and rtA181S in 2 cases. rtA181S without rtM204I/V was found in one patient. Four of the six patients (67%) without 24 month CVR showed rtA181S or rtT184S substitutions either alone or with typical lamivudine resistance profiles. Baseline HBV-DNA levels were negatively associated with IVR (univariate analysis, P=0.023). At least one of rtA181S and rtT184S substitutions correlated negatively with IVR and CVR (univariate analysis, P=0.001) and was independently associated with absence of CVR (P = 0.016). CONCLUSIONS: Lamivudine monotherapy favours the emergence of viral quasispecies that influence the response rate to adefovir rescue therapy independently from baseline viraemia and lower the susceptibility to other nucleos(t)ide analogues.


Assuntos
Antivirais/farmacologia , DNA Polimerase Dirigida por DNA/genética , Farmacorresistência Viral/genética , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Hepatite B/tratamento farmacológico , Hepatite B/virologia , Lamivudina/farmacologia , DNA Polimerase Dirigida por RNA/genética , Adenina/análogos & derivados , Adenina/farmacologia , Adenina/uso terapêutico , Adulto , Idoso , Antivirais/uso terapêutico , DNA Viral/genética , Feminino , Seguimentos , Humanos , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Nucleosídeos/farmacologia , Nucleotídeos/farmacologia , Organofosfonatos/farmacologia , Organofosfonatos/uso terapêutico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Viremia/virologia
6.
J Med Virol ; 75(1): 20-6, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15543588

RESUMO

Albania is a Mediterranean country, still with a high endemicity level of hepatitis B virus (HBV) infection. The chronic hepatitis B profile was characterized in this geographical area and used as a model to investigate the impact of endemicity level on the prevalence of the two major forms of chronic hepatitis B (HBeAg-positive and HBeAg-negative chronic hepatitis B). A cross-sectional study was conducted among 62 chronic hepatitis B patients consecutively admitted to the most important tertiary health care center for the diagnosis and treatment of liver disease in Albania. HBV-DNA was measured with an in-house PCR with a sensitivity of 10(4) copies/ml which uses primers encompassing the pre-core/core region. PCR products were subjected to sequencing and oligohybridization assay. Of the 62 patients, 75.8% had HBeAg-negative chronic hepatitis B. Genotype D was found in all 39 patients with detectable HBV viremia, for whom the heterogeneity of the region modulating HBeAg expression was assessed. Basic core promoter (BCP) mutations (1762/1764) were observed more often in anti-HBe-positive and older patients. In more than 90% of the HBeAg-negative chronic hepatitis B patients with detectable viremia, HBV that carries the G to A pre-core mutation at nucleotide 1896 was found. Patients with HBeAg-positive chronic hepatitis B were younger than HBeAg-negative chronic hepatitis B patients, and for symptomatic and asymptomatic liver-disease patients, the age of peak prevalence was at least 10 years lower for HBeAg-positive chronic hepatitis B patients. In conclusion, the virological and clinical pattern of chronic hepatitis B in Albania is similar to that observed in other Mediterranean countries; it seems to be independent of the HBV endemicity level.


Assuntos
Vírus da Hepatite B/genética , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/virologia , Adulto , Fatores Etários , Idoso , Albânia/epidemiologia , DNA Viral/sangue , DNA Viral/química , Variação Genética , Genótipo , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/classificação , Vírus da Hepatite B/isolamento & purificação , Humanos , Fígado/patologia , Pessoa de Meia-Idade , Epidemiologia Molecular , Hibridização de Ácido Nucleico , Mutação Puntual/genética , Regiões Promotoras Genéticas/genética , Análise de Sequência de DNA , Viremia
7.
Mycopathologia ; 119(3): 129-32, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1435953

RESUMO

The growth of Cryptococcus neoformans in a minimal liquid synthetic medium with or without thiamine (10 micrograms/ml) was investigated. In these media the presence or absence of thiamine had no effect on the development of C. neoformans. To check these results, we performed a series of experiments on a solid form of the minimal synthetic medium. In this study a series of six serial transfers were carried out to starve the cells of nutrients that may have been carried over from their growth on rich media. In each of the transfers on the solid synthetic medium, C. neoformans showed a similar and scarce growth. This finding indicates that C. neoformans could be autotrophic in respect to thiamine.


Assuntos
Cryptococcus neoformans/crescimento & desenvolvimento , Tiamina/fisiologia , Meios de Cultura
8.
Mycopathologia ; 123(1): 19-25, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8247095

RESUMO

Candida albicans starved cells were incubated in minimal synthetic liquid media containing different concentrations of ammonium sulphate (0.00, 0.02, 0.05, 0.10, 0.03, 0.50 g/L). Culture growth was monitored by measuring daily the optical density and by evaluating RNA and protein cellular content after 48 and 96 hours from the inoculum. The environmental availability of ammonium ion influenced the biomass production, that was maximum when its concentration was 0.10 and 0.30 g/L. In addition, an effect on cell duplication time was observed, this was particularly evident when the (NH4)2SO4 concentration was 0.10 g/L. The protein content increased in relation to the increase of ammonium ion availability, with a peak in correspondence to 0.30 g/L and a drop when the greatest concentrations were employed. RNA production was inversely proportional in respect to protein production. The optimal range of ammonium sulphate concentration for C. albicans growth was 0.10-0.30 g/L; over these concentrations there was an inhibitory effect. The rate of the protein and RNA syntheses seems to indicate the growth phase and the nitrogen nutritional conditions of the cultures, respectively.


Assuntos
Sulfato de Amônio/metabolismo , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Proteínas Fúngicas/biossíntese , RNA Fúngico/biossíntese , Sulfato de Amônio/toxicidade , Candida albicans/efeitos dos fármacos , Divisão Celular , Meios de Cultura
9.
G Batteriol Virol Immunol ; 82(1-12): 114-20, 1989.
Artigo em Italiano | MEDLINE | ID: mdl-2490393

RESUMO

Cells of Candida albicans, after 24 hours of growth in YM, were starved, alternatively, in citrate buffer, physiological solution, MMS deprived of glucose or ammonium sulphate. The eventual growth was monitored by determining the absorbance at 675 nm. Simultaneously, the cell morphology was also controlled. In a second series of experiments, the C. albicans cells taken from YM were starved for 72 hours in one of the mediums as stated above, and then reinoculated in MMS liquid without, alternatively, glucose or ammonium sulphate. Again the eventual growth was monitored as in the above method. The achieved results indicate the presence of a reserve of nitrogen, which can be utilized when a source of C is given to the cell. We therefore discuss the apparent lack of glucidic reserve and we propose a method for the consumption of nitrogen reserve. The aim of the work is to define how to obtain cells that contain the smallest amount possible of endogenous reserve.


Assuntos
Candida albicans/crescimento & desenvolvimento , Sulfato de Amônio/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/metabolismo , Meios de Cultura/farmacologia , Metabolismo Energético , Glucose/metabolismo , Glucose/farmacologia , Nitrogênio/metabolismo
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