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1.
N Engl J Med ; 341(1): 22-6, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10387938

RESUMO

BACKGROUND: Hepatitis B virus (HBV) infections in patients who lack detectable hepatitis B surface antigen (HBsAg) are called occult infections. Although such infections have been identified in patients with chronic hepatitis C liver disease, their prevalence and clinical significance are not known. METHODS: With the polymerase chain reaction, we searched for HBV DNA in liver and serum samples from 200 HBsAg-negative patients with hepatitis C virus (HCV)-related liver disease (147 with chronic hepatitis, 48 with cirrhosis, and 5 with minimal histologic changes). One hundred of the patients had detectable antibodies to the HBV core antigen (anti-HBc); 100 were negative for all HBV markers. Eighty-three were treated with interferon alfa. We also studied 50 patients with liver disease who were negative both for HBsAg and for HCV markers. In six patients found to have occult HBV infection, we evaluated possible genomic rearrangements through cloning or direct sequencing procedures. RESULTS: Sixty-six of the 200 patients with chronic hepatitis C liver disease (33 percent) had HBV sequences, as did 7 of the 50 patients with liver disease unrelated to hepatitis C (14 percent, P=0.01). Among the 66 patients, 46 were anti-HBc-positive and 20 were negative for all HBV markers (P<0.001). Twenty-two of these 66 patients (33 percent) had cirrhosis, as compared with 26 of the 134 patients with hepatitis C infection but no HBV sequences (19 percent, P=0.04). HBV sequences were detected in 26 of the 55 patients in whom interferon therapy was ineffective and 7 of the 28 patients in whom interferon therapy was effective (P=0.06). None of the sequenced HBV genomes had changes known to interfere with viral activity and gene expression. CONCLUSIONS: Occult hepatitis B infection occurs frequently in patients with chronic hepatitis C liver disease and may have clinical significance.


Assuntos
DNA Viral/análise , Genoma Viral , Vírus da Hepatite B/genética , Hepatite B/complicações , Hepatite C Crônica/complicações , Adulto , Antivirais/uso terapêutico , DNA Viral/sangue , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Hepatite B/virologia , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/uso terapêutico , Fígado/química , Fígado/patologia , Cirrose Hepática/complicações , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade
2.
J Hepatol ; 30(6): 1023-7, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10406179

RESUMO

BACKGROUND/AIMS: Contradictory data have been reported about the predictive value of the variability in interferon sensitivity determining region (ISDR) of hepatitis C virus (HCV) genotype-1b on response to interferon-alpha (IFN-alpha) therapy. The aim of this study was to examine this issue in a series of patients with long-term response to IFN treatment. METHODS: We retrospectively analyzed 24 patients with chronic HCV genotype-1b infection treated with IFN-alpha (total dose median 677, range 216-1350 MU) selected in 6 Italian Liver Units. These patients were defined as true long-term responders (LTR) since they showed persisting biochemical and virological responses to IFN treatment (mean follow-up 38 months). HCV genomes from pretreatment serum samples were amplified and directly sequenced. The ISDR amino-acid sequences obtained were aligned and compared with the published sequence of HCV-J. RESULTS: Amino-acid substitutions were found in 23 of the 24 patients, and 22 of them showed an H to R amino-acid change at codon 2218. Fourteen patients showed only one mutation (at codon 2218), two had 2, five had 3, one had 4 and one had 5 mutations. When we compared the ISDR sequences from the 24 LTR with those of non-responders (NR), we found no significant correlation between the number of mutations and the response to therapy. CONCLUSIONS: Our results demonstrate that the persisting efficacy of IFN treatment in patients with chronic HCV is not related to the number of ISDR amino acid substitutions of the infecting viruses. Further studies are needed to verify whether other NS5A sequences outside the ISDR might be involved in the mechanisms of IFN resistance.


Assuntos
Hepatite C Crônica/genética , Hepatite C Crônica/terapia , Interferon-alfa/uso terapêutico , RNA Polimerase Dependente de RNA/genética , Proteínas não Estruturais Virais/genética , Adulto , Idoso , Sequência de Aminoácidos , Códon , Feminino , Seguimentos , Humanos , Interferon-alfa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Mutação , Fatores de Tempo
3.
J Chemother ; 9(3): 219-26, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9210006

RESUMO

It is well known that lithium chloride (LiCl) is able to trigger human monocytes to release tumor necrosis factor alpha (TNF alpha). In this study we have evaluated the in vitro effect of LiCl on TNF alpha and interleukin-6 (IL-6) release by monocytes from patients affected by non-metastatic (BCa/M0) and metastatic breast cancer (BCa/M1), preincubated with autologous serum (sPt). Our data demonstrate that monocytes from cancer patients (BCa) treated with LiCl released lower amounts of TNF alpha compared to those from healthy donors (HD). Preincubation in autologous serum (sPt) impaired TNF alpha production by monocytes from BCa with LiCl. On the contrary, our data indicate that IL-6 production by monocytes treated was not impaired. Moreover, the results obtained from the same cells, preincubated in sPt and treated with LiCl, indicate that serum factors may synergize with LiCl treatment in releasing IL-6.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Interleucina-6/biossíntese , Cloreto de Lítio/uso terapêutico , Monócitos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossíntese , Idoso , Neoplasias da Mama/sangue , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Monócitos/metabolismo
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