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1.
J Viral Hepat ; 20(2): 85-94, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23301543

RESUMO

In persistent hepatitis C virus (HCV) infection, HCV-specific cytotoxic T lymphocyte (CTL) reactivity is impaired and this affects HCV control. Interleukin-7 receptor (CD127) expression on these cells could regulate CTL reactivity through Mcl-1/Bim balance modulation. Bim is a pro-apoptotic molecule blocked by the action of Mcl-1. Mcl-1/Bim expression and T cell reactivity on HCV-specific CTLs were compared according to CD127 phenotype. Peripheral blood lymphocytes (PBL) from HLA-A2(+) HCV(+) patients were obtained. HCV-specific CTLs were visualized by staining PBL with anti-CD8 and HLA-A2/peptide pentameric complexes (pentamer). Mcl-1/Bim/CD127 phenotype of HCV-specific CTLs was tested by staining detectable CD8(+)/pentamer(+) cells with anti-Mcl-1/Bim/CD127 antibodies. HCV-specific CTL proliferation ability after specific in vitro challenge was tested in the presence and absence of pancaspase inhibitor z-VAD-fmk. All stained cells were analysed by flow cytometry. CD127(low)-expressing HCV-specific CTLs associated with high HCV viraemia, while CD127(high) correlated with undetectable viral loads (P < 0.001). Directly ex vivo, pentamer(+) cell frequency was similar according to CD127 expression level. Nevertheless, CD127(low) pentamer(+) cell proliferation after specific in vitro challenge was impaired (P < 0.05), although this was corrected by z-VAD-fmk treatment (P < 0.05). Mcl-1 expression was low directly ex vivo (P < 0.01), and Bim was up-regulated after antigen encounter (P < 0.05) of CD127(low) pentamer(+) cells. The ex vivo difference between Mcl-1 and Bim expression on pentamer(+) cells correlated positively with CD127 expression level (P < 0.001) and with pentamer(+) cell reactivity (P < 0.05). In summary, a low ex vivo Mcl-1 expression and Bim up-regulation after antigen encounter are involved in CD127(low) HCV-specific CTL hyporeactivity during chronic infection, but it can be overcome by apoptosis blockade.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Hepacivirus/imunologia , Hepatite C Crônica/imunologia , Subunidade alfa de Receptor de Interleucina-7/genética , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Linfócitos T Citotóxicos/fisiologia , Adulto , Apoptose , Proteína 11 Semelhante a Bcl-2 , Proliferação de Células , Células Cultivadas , Estudos Transversais , Regulação para Baixo , Feminino , Hepacivirus/fisiologia , Hepatite C Crônica/metabolismo , Hepatite C Crônica/virologia , Interações Hospedeiro-Patógeno , Humanos , Interferon gama/metabolismo , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Masculino , Pessoa de Meia-Idade , Proteína de Sequência 1 de Leucemia de Células Mieloides , Fenótipo , Linfócitos T Citotóxicos/virologia , Replicação Viral
2.
Aliment Pharmacol Ther ; 31(1): 120-4, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19709096

RESUMO

BACKGROUND: Azathioprine (AZA) liver toxicity arises in approximately 3% of inflammatory bowel disease patients and may result in treatment discontinuation. AIM: To describe the tolerance to mercaptopurine (MP) in patients with previous AZA-related liver injury. METHODS: Retrospective description of 31 patients (14 Crohn's, 17 ulcerative colitis), in which AZA therapy was interrupted because of liver injury, with MP started as alternative therapy. RESULTS: Mean AZA dose was 2.2 +/- 0.4 mg x kg/day. Median (interquartile range) of AZA exposure when liver injury was detected was 2 months (1-5.2). The type of AZA-related injury was cytolitic in 32%, cholestatic in 39% and mixed in 29%. After a median of 2.5 months (0.7-5.2), the therapy was switched to MP at a mean dose of 1.3 +/- 0.2 mg x kg/day. Median of follow-up of MP therapy was 32 months (8-54). In 87.1% of patients (95%CI: 70-96%), MP was tolerated without further liver injury; of these, 77.4% tolerated full MP doses and 9.7% tolerated lower doses. In a further cohort of 12.9% of patients, (95%CI: 3-29%), liver injury reappeared (two cholestasis, two mixed), 1-3 months after the onset of MP exposure. CONCLUSION: The administration of MP is a good alternative in patients with AZA-related liver injury, before thiopurines are definitely discarded.


Assuntos
Azatioprina/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Mercaptopurina/uso terapêutico , Adolescente , Adulto , Colite Ulcerativa/complicações , Doença de Crohn/complicações , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
3.
Am J Transplant ; 6(10): 2348-55, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16869810

RESUMO

Hepatitis C recurrence after liver transplantation (LT) is universal, and frequently leads to cirrhosis and death. The aim of our study was to assess the efficacy and safety of 48-weeks of full-dose peg-interferon-alpha-2a (n = 4) or alpha-2b (n = 51) plus ribavirin (>11 mg/kg/day) in a multicentric cohort of 55 patients > or =12 months after LT. All subjects had histologically proven HCV recurrence, excluding severe cholestatic recurrence. Mean age was 54.3 +/- 9.7, 77% male, 90.9% genotype 1, 32.7% cirrhotics. All but 5 patients received monotherapy with tacrolimus (54.5%), cyclosporine (30.7%) or mycophenolate mofetil (5.5%). The rates of end-of-treatment response and sustained virological response (SVR) were 66.7% and 43.6%, respectively. Low baseline HCV-RNA (p = 0.005) and a length from LT to therapy between 2-4 years (p = 0.011) were predictors of SVR. The lack of achieving a viral load decrease > or =1-log10 at week 4 and/or 2-log10 at week 12 was 100% predictive of failure. The most frequent side effects were neutropenia (76,4%), anemia (60%) and infectious complications (30.9%). Toxicity led to peg-interferon withdrawal in 16 (29%) subjects. In 15 patients with post-treatment biopsy, the histological activity index was significantly improved (p = 0.006), whereas fibrosis did not change (p = 0.14). Three patients died (cholangitis, hepatic artery thrombosis and lung cancer). In conclusion, HCV therapy after LT was very effective, although it led to a significant rate of toxicity.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C , Interferon-alfa/uso terapêutico , Transplante de Fígado/efeitos adversos , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Adolescente , Adulto , Idoso , Biópsia , Feminino , Seguimentos , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C/patologia , Hepatite C/virologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , Proteínas Recombinantes , Recidiva , Estudos Retrospectivos , Transplante Homólogo , Resultado do Tratamento
4.
J Viral Hepat ; 13(7): 466-73, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16792540

RESUMO

To evaluate, among 70 hepatitis C virus (HCV)-monoinfected and 36 human immunodeficiency virus (HIV)-coinfected naïve patients with genotypes 1/4 receiving weight-adjusted pegylated interferon-alpha-2b/ribavirin, viral kinetics and the feasibility to predict treatment failure measuring early HCV-RNA decreases. HCV-RNA was assessed at baseline, weeks 4, 12 and 24. Receiver operating characteristic (ROC) curves were calculated to determine the most sensitive cut-off values of viral decrease at week 4 predicting treatment failure. Baseline predictors of failure were evaluated by univariate and multivariate analyses. Despite similar baseline HCV-RNA (5.75 vs 5.72 log(10)IU/ml, P = 0.6), HCV monoinfection led to significantly lower HCV-RNA values at weeks 4 (3.7 vs 4.3 log(10)IU/ml, P = 0.01), 12 (2.3 vs 3.5 log(10)IU/ml, P = 0.01) and 24 (1.4 vs 3.3 log(10)IU/ml, P = 0.001) and a higher rates of viral clearance at weeks 24 (60%vs 36%, P = 0.02), 48 (46%vs 25%, P = 0.03) and 72 (37%vs 17%). The lack of achieving an HCV-RNA decrease of at least 1 log(10) at week 4 was highly predictive of treatment failure for HCV-monoinfected patients (Se 100%, Sp 50%, positive predictive value (PPV) 57%, negative predictive value (NPV) 100%, ROC curve area, 0.86 [95% confidence interval (CI) 0.77-0.95], but not for HCV/HIV-coinfected patients (cut-off, 0 log(10), Se 100%, Sp 27%, PPV 21%, NPV 100%, ROC curve area, 0.71 (95% CI 0.49-0.93). HIV coinfection was independently associated with failure (odds ratio 2.95, 95% CI 1.08-8.04, P = 0.01). Thus the magnitude of HCV-RNA decreases at week 4 correlated with treatment response. Significant differences in viral kinetics and cut-off values predicting nonresponse suggest a slower HCV clearance rate in HIV coinfection, which was independently associated with treatment failure.


Assuntos
Antivirais/uso terapêutico , Soropositividade para HIV/virologia , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Feminino , Genótipo , HIV/imunologia , Soropositividade para HIV/metabolismo , Hepacivirus/isolamento & purificação , Hepacivirus/metabolismo , Hepatite C/imunologia , Humanos , Interferon alfa-2 , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis , Estudos Prospectivos , RNA Viral/metabolismo , Proteínas Recombinantes
6.
Transplant Proc ; 37(9): 3963-4, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16386597

RESUMO

The efficacy of pegylated interferon (p-IFN) and ribavirin (RB) in transplant patients is not well known. Chronic hepatitis C evolves in a more aggressive form after transplantation, causing a worse survival. Twenty-one naïve patients with recurrent chronic hepatitis C demonstrated by biopsy were treated for 48 weeks with p-IFN alpha2b (1.5 microg/kg/wk) and RB (>10.6 mg/kg/d). Quantification of RNA was performed (Amplicor Cobas 2.0 Roche) at baseline, 4, 12, 24, 48, and 72 weeks. A qualitative technique was used when quantitative levels were undetectable. At more than 1 year since liver transplantation we did not detect coinfection with human immunodeficiency virus or use steroid treatment. Among the cohort there were 16 men (76.2%). The mean overall age was 52 +/- 12 years. Time from liver transplant to treatment was 1637 +/- 1030 days. They were all infected with genotype 1. Eight patients received cyclosporine and the others tacrolimus. One patient was coinfected with hepatitis B virus and was receiving lamivudine. The mean initial histological activity index was 6.9 +/- 1.5 and fibrosis, 2.52 +/- 1.8 (Ishak). Two patients needed spleen embolization before the treatment. Two patients had to stop the treatment: one due to clinical intolerance, and the other one due to a cholangitis. In 14%, p-IFN doses were adjusted. In 32% RB was adjusted. Five (23.8%) did not respond at 24 weeks. Fourteen (66.7%) showed end-treatment responses but four relapsed at 72 weeks. A sustained viral response was achieved in 9 (42.8%). One patient died due to arterial thrombosis just after completing the treatment.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Transplante de Fígado , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Biópsia , Feminino , Hepatite B/tratamento farmacológico , Hepatite C Crônica/patologia , Humanos , Interferon alfa-2 , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Recidiva , Resultado do Tratamento
7.
Med Clin (Barc) ; 116(4): 125-8, 2001 Feb 03.
Artigo em Espanhol | MEDLINE | ID: mdl-11222157

RESUMO

BACKGROUND: To study the hepatitis B virus (HBV) transmission from donors HBsAg-/AntiHBc+ to liver transplant recipients. PATIENTS AND METHOD: We studied retrospectively the HBV serological markers in 43 donors from our center and also the serological condition of the 41 recipients. The HBV serological markers were analyzed by ELISA and HBV DNA was detected by hybridation assays. RESULTS: 13 donors samples showed some HBV serological markers: 6 anti-HBc and anti- HBs (13.9%), 4 anti-HBc (9%) and 3 anti- HBs (6.9%). There were no cases of hepatitis B among liver recipients from donors with negative serological markers. Among the 13 recipients with HBV serological markers, 9 were followed during 39 (SD 17) months. The 5 recipients with no HBV markers, who received an anti- HBc+ with or without anti- HBs (100%) developed hepatitis B. The two liver recipients with anti-HBs solely, did not developed infection (0%). Of the 41 recipients, 15 had some HBV markers before transplant and two of them received an anti-HBc+ and did not develop the infection (0%). CONCLUSIONS: In our study, the prevalence of serological HBV infection in donors and recipients was of 30.2 and 31.7%, respectively. Anti-HBc with or without anti-HBs donors transmitted the HBV infection in all the cases (100%) to the susceptible recipients. The presence of anti-HBs in recipients protected these against the infection. Only the anti-HBs positive donors did not trasmit the HBV infection.


Assuntos
Hepatite B/transmissão , Transplante de Fígado , Doadores de Tecidos , Adulto , DNA Viral/análise , Feminino , Hepatite B/imunologia , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Humanos , Transplante de Fígado/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Risco
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