Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Viral Hepat ; 19(10): 724-31, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22967104

RESUMO

Quantitative hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) assays are emerging as effective tools of on-treatment predictors of response to antiviral agents, in addition to monitoring serum HBV DNA levels. However, the dynamic relationship between quantitative HBsAg, as well as HBeAg and HBV DNA, and the predictability of subsequent clinical outcomes during entecavir (ETV) therapy remain unclear. Eighty-two patients with HBeAg-positive chronic hepatitis B (CHB) received ETV therapy for ≥3 years. Virologic response (VR) after 3 years of ETV therapy was achieved in 73 (89.0%) patients. Among baseline and on-treatment factors, on-treatment HBV DNA levels performed better with respect to the prediction of response than HBsAg and HBeAg levels. Especially, the performance of absolute values of HBV DNA with respect to response was superior to HBV DNA decline from the baseline. The best predictive value was an absolute HBV DNA level of 2.3 log(10) IU/mL at month 6 (areas under the curve [AUROC], 0.977; 95% CI, 0.940-1.000; P < 0.001). HBeAg seroconversion after 3 years of therapy was achieved in 26 (31.7%) patients. On-treatment HBeAg levels performed better with respect to the prediction of seroconversion than HBsAg and HBV DNA levels. The best cut-off value for the HBeAg level at month 12 for the prediction of seroconversion was 0.62 log(10) PEIU/mL. Although the HBsAg level at baseline is often used to predict the antiviral potency of entecavir, on-treatment HBV DNA and HBeAg levels are more helpful for prediction of subsequent clinical outcomes in HBeAg-positive CHB patients with entecavir treatment.


Assuntos
Antivirais/administração & dosagem , DNA Viral/sangue , Monitoramento de Medicamentos/métodos , Guanina/análogos & derivados , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Adulto , Feminino , Guanina/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Resultado do Tratamento
2.
Neuroscience ; 179: 1-8, 2011 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-21277949

RESUMO

Adolescence is a critical vulnerable period during which exposure to nicotine greatly enhances the possibility to develop drug addiction. Growing evidence suggests that serotonergic (5-HT) neurotransmission may contribute to the initiation and maintenance of addictive behavior. As the dorsal raphe (DR) and median raphe (MnR) nuclei are the primary 5-HT source to the forebrain, the current study tested the hypothesis that there are age-dependent effects of acute nicotine administration on activation of 5-HT neurons within these regions. Both adolescent (Postnatal day 30) and adult (Postnatal day 70) male Sprague-Dawley rats received subcutaneous injection of either saline or nicotine (0.2, 0.4, or 0.8 mg/kg). Subsequently, the number of 5-HT cells that were double-labeled for Fos and tryptophan hydroxylase was counted in seven subregions within the DR and the entire MnR. The results show that acute nicotine injection induces Fos expression in 5-HT neurons in a region-specific manner. In addition, adolescents show broader regional activations at either a lower (0.2 mg/kg) and a higher (0.8 mg/kg) dose of nicotine, displaying a unique U-shape response curve across doses. In contrast, 5-HT cells with activated Fos expression were restricted to fewer regions in adults, and the patterns of expression were more consistent across doses. The results reveal dose-dependent effects of nicotine during adolescence with apparent sensitization at different ends of the dosage spectrum examined compared to adults. These data indicate that initial exposure to nicotine may have unique effects in adolescence on the ascending 5-HT system, with the potential for consequences on the affective-motivational qualities of the drug and the subsequent propensity for repeated use.


Assuntos
Comportamento Aditivo/metabolismo , Neurônios/efeitos dos fármacos , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Núcleos da Rafe/efeitos dos fármacos , Fatores Etários , Animais , Comportamento Aditivo/fisiopatologia , Imuno-Histoquímica , Masculino , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-fos/biossíntese , Proteínas Proto-Oncogênicas c-fos/efeitos dos fármacos , Núcleos da Rafe/metabolismo , Ratos , Ratos Sprague-Dawley , Serotonina/metabolismo
3.
J Viral Hepat ; 12(4): 393-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15985010

RESUMO

The efficacy of lamivudine re-treatment in chronic hepatitis B (CHB) patients who relapse after HBeAg seroconversion with lamivudine has not been investigated. The aim of this study was to evaluate the efficacy of lamivudine re-treatment in relapsed patients. Among 192 patients who had achieved HBeAg seroconversion with lamivudine at a dose of 100 mg/day, 121 patients discontinued lamivudine. Relapse occurred in 49 patients (40.5%). Thirty-three relapsed patients received lamivudine re-treatment for at least 6 months. The mean duration of lamivudine re-treatment was 16 months and the follow-up period was 8.9 months. HBeAg seroconversion was achieved in 23 patients (69.7%). The cumulative HBeAg seroconversion rates at 5, 9, and 12 months were 60, 64, and 67%, respectively. The mean time to HBeAg seroconversion in lamivudine re-treatment was shorter than that in the initial therapy (4.7 months vs. 9.7 months). Viral breakthrough occurred in six (18.2%) patients. All patients with viral breakthrough were accompanied by elevation of serum alanine aminotransferase (ALT) levels. Among 15 patients who discontinued lamivudine re-treatment after HBeAg seroconversion, relapse occurred in six patients (40%). All relapses occurred within 9 months after the discontinuation of lamivudine re-treatment. In conclusion, lamivudine re-treatment in relapsed patients after initial lamivudine therapy had a higher response rate and shorter duration to HBeAg seroconversion than during the initial therapy. However, HBeAg seroconversion induced by lamivudine re-treatment was not durable.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Adulto , Alanina Transaminase/sangue , Antivirais/administração & dosagem , Feminino , Antígenos E da Hepatite B/sangue , Humanos , Lamivudina/administração & dosagem , Masculino , Recidiva , Retratamento
4.
J Viral Hepat ; 12(2): 216-21, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15720539

RESUMO

The aim of this study was to determine whether the changing patterns of quantitative hepatitis B e antigen (HBeAg) levels by serial monitoring could predict HBeAg seroconversion and viral breakthrough during lamivudine therapy. We retrospectively analysed 340 HBeAg positive naive chronic hepatitis B patients treated with lamivudine. The mean duration of lamivudine therapy was 18.7 (range 6-56) months. The changing patterns and reduction rates of pretreatment HBeAg levels by serial monitoring were categorized into three groups: Decrescendo group (n = 195), Decrescendo-crescendo group (n = 65) and no changing or fluctuating group (n = 80). Of 109 patients who had achieved HBeAg seroconversion, 105 (96.3%) were included in the decrescendo group. The decrescendo group, pretreatment quantitative HBeAg levels, alanine aminotransferase levels, and the duration of lamivudine therapy were independent predictive factors for HBeAg seroconversion. Of 82 patients who had viral breakthrough, 53 (64.6%) were in the decrescendo-crescendo group and 21 (25.6%) were in the no changing or fluctuating group. The only predictive factor for viral breakthrough was the changing patterns of quantitative HBeAg levels, especially, the decrescendo-crescendo group and the no changing or fluctuating group. The mean time of turning points in the decrescendo-crescendo group was 7.1 months earlier than the mean time of viral breakthrough (9.0 months vs 16.5 months). Therefore, the changing patterns of quantitative HBeAg levels by serial monitoring during lamivudine therapy may allow not only the prediction of treatment responses, but also an early recognition of a viral breakthrough.


Assuntos
Antígenos E da Hepatite B/imunologia , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Lamivudina/uso terapêutico , Adolescente , Adulto , Fatores Etários , Idoso , Biomarcadores/análise , Estudos de Coortes , Intervalos de Confiança , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Antígenos E da Hepatite B/análise , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Fatores Sexuais , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...