RESUMO
Nucleos(t)ide analogues (NA) are effective in suppressing hepatitis B virus (HBV) replication, but most patients require long-term treatment. This study aimed to investigate switching to peginterferon as a strategy to stop NA. Hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients who developed HBeAg seroconversion during NA treatment were studied. All patients received open-label peginterferon alfa-2a 180 µg/wk for 48 weeks, and NA was stopped at week 4 of peginterferon treatment. The primary endpoint was sustained response, which was defined as negative HBeAg, positive anti-HBe and HBV DNA <2000 IU/mL at week 72. Other secondary endpoints including HBsAg loss at week 72 were also studied. Forty-one patients treated with entecavir for 56 ± 23 months were recruited. Sustained response was achieved in 30 patients (73%, 95% confidence interval 58%-84%). At week 72, 31 (76%) patients had HBeAg seroconversion, 56 (23%) patients had undetectable HBV DNA, 31 (76%) patients had normal ALT, and 6 patients (15%) had HBsAg loss. Baseline HBsAg level was the best predictor for both sustained response and HBsAg loss; the best HBsAg cut-off for sustained response was <1500 IU/mL and that for HBsAg loss was <500 IU/mL by receiver operating characteristic curve analysis. Twenty-two of 25 (88%) patients with baseline HBsAg <1500 IU/mL had sustained response. Five of 10 (50%) patients with baseline HBsAg <500 IU/mL developed HBsAg loss. Switching to peginterferon can be considered as a treatment option in NA-treated patients with HBeAg seroconversion, particularly among those with lower HBsAg levels.
Assuntos
Substituição de Medicamentos , Guanina/análogos & derivados , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adolescente , Adulto , Idoso , Antivirais , Feminino , Guanina/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Soroconversão , Resultado do Tratamento , Adulto JovemRESUMO
Frequency compression (FC) is an effective alternative to conventional amplification for patients with severe-to-profound middle- and high-frequency hearing loss and with some residual low frequency hearing. The present work investigated the underlying factors accounting for the intelligibility of FC-processed speech. Eighteen normal-hearing participants listened to FC-processed Mandarin sentences, and testing conditions included two compression strategies (i.e., linear and nonlinear), four degrees of compression, and two segmental conditions (i.e., vowel-center and vowel-onset). Results showed that the nonlinear strategy outperformed the linear strategy in enhancing the intelligibility of FC-processed sentences. A small frequency range of source compression region involved a lesser degree of compression, and favored a higher intelligibility score. Vowel segments carried a large amount of intelligibility information contained in nonlinearly frequency-compressed sentences, but could not fully account for the intelligibility improvement from nonlinear frequency-compression. The intelligibility benefit of FC-processed Mandarin sentences may be partially attributed to the additional F1-F2 transitional spectral envelope cue provided by nonlinear FC with the F1-included spectral region preserved.