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1.
Aliment Pharmacol Ther ; 48(5): 564-573, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29963713

RESUMO

BACKGROUND: Host genetic modifiers of the natural history of chronic hepatitis B (CHB) remain poorly understood. Recently, a genome-wide association study (GWAS)-identified polymorphism in the STAT4 gene that contributes to the risk for hepatocellular carcinoma (HCC) was shown to be associated with the full spectrum of hepatitis B virus (HBV) outcomes in Asian patients. However, the functional mechanisms for this effect are unknown and the role of the variant in modulating HBV disease in Caucasians has not been investigated. AIMS: To determine whether STAT4 genetic variation is associated with liver injury in Caucasian patients with CHB and to investigate potential mechanisms mediating this effect. METHODS: STAT4 rs7574865 was genotyped in 1085 subjects (830 with CHB and 255 healthy controls). STAT4 expression in liver, PBMCs and NK cells, STAT4 phosphorylation and secretion of interferon-gamma (IFN-γ) according to STAT4 genetic variation was examined. RESULTS: STAT4 rs7574865 genotype was independently associated with hepatic inflammation (OR: 1.42, 95% CI: 1.07-2.06, P = 0.02) and advanced fibrosis (OR: 1.83, 95% CI: 1.19-2.83, P = 0.006). The minor allele frequency of rs7574865 was significantly lower than that in healthy controls. rs7574865 GG risk carriers expressed lower levels of STAT4 in liver, PBMCs and in NK cells, while NK cells from patients with the risk genotype had impaired STAT4 phosphorylation following stimulation with IL-12/IL-18 and a reduction in secretion of IFN-γ. CONCLUSION: Genetic susceptibility to HBV persistence, hepatic inflammation and fibrosis in Caucasians associates with STAT4 rs7574865 variant. Downstream effects on NK cell function through STAT4 phosphorylation-dependent IFN-γ production likely contribute to these effects.


Assuntos
Hepatite B Crônica/complicações , Hepatite B Crônica/genética , Cirrose Hepática/genética , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genética , População Branca , Adulto , Estudos de Casos e Controles , Células Cultivadas , Feminino , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Hepatite B Crônica/etnologia , Humanos , Cirrose Hepática/etnologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , População Branca/genética , População Branca/estatística & dados numéricos
2.
Panminerva Med ; 57(4): 201-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25897630

RESUMO

Hepatitis B virus (HBV) infection is still a relevant problem worldwide and many cases of hepatocellular carcinoma (HCC) are related to HBV. The prognosis of HBV-related HCC is poor, particularly for advanced stage diagnosis. Although follow-up strategies were adopted for patients at risk, there is need for an optimal early biomarker for the screening purpose. MicroRNAs (miRNAs) are small non-coding RNAs, tightly connected to cell type and differentiation status and act as genetic regulator which can be involved in oncogenic processes. The alteration in miRNA expression pattern may represent a new opportunity for HBV-related HCC diagnosis and therapies. Some studies focused on miRNA polymorphism responsible for HCC susceptibility; others found several miRNAs deregulated by HBV X protein as well as miRNAs altered in HBV-related HCC tissue and cells. A high variability among results emerged, probably due to different techniques employed, biological substrates, experimental procedures, criteria of miRNAs selection and ethnic provenience of the included patients. Interestingly, circulating miRNAs have been studied as potential HCC-biomarkers but the reported accuracy is still not convincing, particularly in distinguishing patients with HCC from patients with cirrhosis. Hence, the use of miRNAs remains in an experimental phase and more studies are required to define their role in the clinical practice.


Assuntos
Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/fisiologia , Neoplasias Hepáticas/virologia , MicroRNAs/genética , Predisposição Genética para Doença , Humanos , MicroRNAs/sangue
3.
Aliment Pharmacol Ther ; 41(10): 939-48, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25801076

RESUMO

BACKGROUND: The PNPLA3/Adiponutrin rs738409 C/G single nucleotide polymorphism is associated with the severity of steatosis, steatohepatitis and fibrosis in patients with non-alcoholic fatty liver disease, as well as the severity of steatosis and fibrosis in patients with chronic hepatitis C (CHC). AIM: To test in genotype 1(G1)-CHC patients, the putative association between the PNPLA3 variant and histological features of steatohepatitis, as well as their impact on the severity of fibrosis. METHODS: Four hundred and thirty-four consecutively biopsied Caucasian G1-CHC patients were genotyped for PNPLA3 rs738409, its effect evaluated by using an additive model. Histological features of steatohepatitis in CHC were assessed using the Bedossa classification. Hepatic expression of PNPLA3 mRNA was evaluated in 63 patients. RESULTS: The prevalence of steatohepatitis increased from 16.5% in patients with PNPLA3 CC, to 23.2% in CG and 29.2% in the GG genotype (P = 0.02). By multiple logistic regression, PNPLA3 genotype (OR 1.54, 95% CI 1.03-2.30, P = 0.03), together with age (OR 1.03, 95% CI 1.00-1.05, P = 0.02), BMI ≥ 30 (OR 2.06, 95% CI 1.04-4.10, P = 0.03) and homoeostasis model assessment (HOMA, OR 1.18, 95% CI 1.04-1.32, P = 0.006) were independently linked to steatohepatitis. When stratifying for obesity, PNPLA3 was associated with NASH in non-obese patients only (12.0% in CC vs. 18.3% in CG vs. 27.3% in GG, P = 0.01), including after correction for metabolic confounders (OR 2.06, 95% CI 1.26-3.36, P = 0.004). We showed an independent association between steatohepatitis (OR 2.05, 95% CI 1.05-4.02, P = 0.003) and severe fibrosis. Higher liver PNPLA3 mRNA was associated both with the severity of steatosis (adjusted P = 0.03) and steatohepatitis after adjusting for gender, age, BMI and HOMA (P = 0.002). CONCLUSION: In patients with genotype 1 hepatitis C, the PNPLA3 G variant is associated with a higher risk of steatosis severity and steatohepatitis, particularly among non-obese subjects.


Assuntos
Fígado Gorduroso/genética , Hepatite C Crônica/genética , Lipase/genética , Proteínas de Membrana/genética , Hepatopatia Gordurosa não Alcoólica/genética , Adulto , Estudos de Coortes , Fígado Gorduroso/patologia , Feminino , Genótipo , Hepacivirus/genética , Humanos , Cirrose Hepática/patologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/epidemiologia , Polimorfismo de Nucleotídeo Único , População Branca/genética
4.
Minerva Gastroenterol Dietol ; 61(2): 61-70, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25323305

RESUMO

There are currently several drugs approved for the treatment of chronic hepatitis B including recombinant interferons, such as interferon-α and its pegylated formulation, and the nucleos(t)ide analogues, such as lamivudine, adefovir, telbivudine, entecavir and tenofovir. Pegylated-interferon is an immune-modulatory agent that works mainly by enhancing the innate immune response while nucleos(t)ide analogues are oral drugs with direct inhibition of viral replication. Each agent has its own advantages and drawbacks. Pegylated-Interferon treatment has a finite duration without induction of drug resistance but only a limited number of patients achieve a sustained virological response to therapy. On the other hand, the care with nucleos(t)ide analogues requires a long-term treatment with a potential risk of induction of drug resistance, but higher rates of viral replication suppression are achieved. Nevertheless, second generation nucleos(t)ide analogues, such as Entecavir and Tenofovir, have both high genetic barrier to resistance and potent antiviral action. This review describes the mechanisms of antiviral activity and the efficacy of viral suppression of the different available drugs for chronic hepatitis B treatment, considering the recent clinical guidelines for an optimal management of chronic HBV infection.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Genótipo , Hepatite B/genética , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/sangue , Humanos , Guias de Prática Clínica como Assunto
5.
Genes Immun ; 14(5): 286-90, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23594959

RESUMO

IL28B polymorphisms strongly predict spontaneous and treatment-induced clearance of hepatitis C virus (HCV) infection. A recent study proposed a 32-base pair deletion in the CC-chemokine receptor 5 (CCR5) gene (CCR5-Δ32) interacting with the IL28B polymorphisms to influence spontaneous HCV clearance. The aim of this study was to clarify the role of CCR5-Δ32 in treatment-induced clearance of chronic hepatitis C (CHC). A cross-sectional cohort of 813 Caucasian patients with CHC genotype 1 (365 responders and 448 non-responders) who had received standard of care dual therapy with interferon (IFN)-α and ribavirin (RBV) was genotyped for the CCR5-Δ32 and IL28B polymorphisms to examine their interaction with respect to treatment response. CCR5-Δ32 did not influence treatment-induced recovery to IFN-α/RBV in CHC, and did not improve prediction of sustained virological response in the context of the IL28B polymorphisms in a multivariate model. CCR5-Δ32 homozygotes were significantly more frequent in those with CHC than healthy controls in the European cohorts (2.9% vs 0.4%, P<0.0001), but not in Australians of European ancestry. In conclusion, CCR5-Δ32 does not influence treatment response in the context of IL28B polymorphisms. Although CCR5-Δ32 may affect viral clearance within closely controlled geographical and genetic environments, we found no effect in larger cohorts treated with dual therapy.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Receptores CCR5/genética , Deleção de Sequência , Adulto , Austrália , Sequência de Bases , Estudos de Coortes , Estudos Transversais , Quimioterapia Combinada , Epistasia Genética , Europa (Continente) , Feminino , Genótipo , Hepatite C Crônica/etnologia , Hepatite C Crônica/genética , Humanos , Interferon-alfa/uso terapêutico , Interferons , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Ribavirina/uso terapêutico , Resultado do Tratamento , População Branca/genética
8.
J Viral Hepat ; 13(6): 355-62, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16842437

RESUMO

In this study, we compare results obtained by sequences analysis and commercial kits in the detection of hepatitis B virus (HBV) polymerase and precore (PC) and core promoter mutations. A total of 23 serum samples from lamivudine treated patients were tested for polymerase mutations by direct sequencing, INNO-LiPA HBV DR and AFFIGENE HBV DE/3TC. Full concordance among the three assays was observed in 63% of the total analysed codons. Concordant results were obtained between sequencing and LiPA in 80%, between sequencing and AFFIGENE in 73% and between LiPA and AFFIGENE in 74% of all tested codons. All discrepancies were observed in mixed population samples in which AFFIGENE and LiPA detected additional viral variants not revealed by sequence. In two patients, with serial samples, LiPA detected earlier than sequence and AFFIGENE an emerging mutate strain. PC and core promoter viral variants were detected in 28 serum samples collected from 14 HBV inactive carriers and from 14 hepatitis B patients with chronic liver disease. Direct sequencing, INNO-LiPA HBV PreCore and AFFIGENE HBV MUTANT VL 19 showed fully coincident results in 88% of tested positions. These findings showed that all assays evaluated were sensitive and accurate tools to analyse HBV genomic variability. Sequence analysis is essential to study new emerging mutations as LiPA and AFFIGENE assays are more easily useful in clinical laboratories to detect the appearance of well-characterized HBV variants.


Assuntos
Análise de Sequência de DNA/métodos , Sondas de DNA , DNA Viral/análise , Hepatite B/tratamento farmacológico , Hepatite B/virologia , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B/enzimologia , Vírus da Hepatite B/genética , Humanos , Lamivudina/uso terapêutico , Mutação , Regiões Promotoras Genéticas , Precursores de Proteínas/genética , DNA Polimerase Dirigida por RNA/genética , Kit de Reagentes para Diagnóstico , Inibidores da Transcriptase Reversa/uso terapêutico
9.
Panminerva Med ; 47(3): 191-4, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16462727

RESUMO

AIM: The trend towards increasing prevalence of Helicobacter pylori (H. pylori) antibiotic resistance may jeopardize the efficacy of most regimens. Culture of the bacterium, the useful method able to address therapy, is influenced by various factors. Thus, validation of the procedure is fundamental. Most studies have been carried out in microbiological settings, while only few have been conducted in clinical frames. We evaluated the accuracy of culture for detection of H. pylori in a clinical dedicated laboratory. METHODS: Forty-six patients (28 females, 18 males, mean age 56+/-4.7 years) were included. Thirty experienced failure to H. pylori eradication after at least 3 courses of treatment. The control group included 16 subjects suffering from gastroesophageal reflux disease and negativity for H. pylori infection. Diagnostic strategy was based on histology, culture testing, serology and 13C-urea breath test. A patient was considered infected if 2 tests were positive. A commercial culture medium in microaerophilic atmosphere was utilized. RESULTS: Out of 30 positive specimens, culture correctly identified 29. In 1 case, no growth of micro-organisms occurred. In the control group, bacterial culture accurately identified all negative samples. One of them indicated growth but neither aspect nor confirmation tests identified H. pylori. Sensitivity was 96.7%, specificity 100%, and accuracy 97.8%. Positive and negative predictive values were 100% and 94.1%, respectively. CONCLUSIONS: Culture of H. pylori is a feasible method and provides a good level of diagnostic accuracy even in a clinical setting by following international guidelines combined with training of specialized personnel.


Assuntos
Testes Respiratórios/métodos , Helicobacter pylori/isolamento & purificação , Ureia/metabolismo , Isótopos de Carbono , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Aliment Pharmacol Ther ; 20(3): 281-7, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15274664

RESUMO

AIM: To evaluate the clinical and virological impact of the prolonged use of lamivudine in 94 patients with HBe antigen-negative chronic hepatitis B. METHODS: Initial virological and biochemical responses were obtained in 84 (89%) and in 83 (88%) patients respectively. RESULTS: The virological response peaked within the first 12 months, but diminished to 39% at 48 months because of drug resistance. Overall a virological breakthrough developed in 44 patients (52.4%). After virological breakthrough, the actuarial probability of maintaining biochemical remission diminished to 15% at 24 months and 0% at 29 months. There was no response in 10.6%. Polymerase gene mutations were observed in 82.5% of virological breakthroughs but also in 75% of the non-responders. Overall 7.4% of patients developed a hepatocellular carcinoma. CONCLUSION: Almost 90% of patients responded initially to lamivudine but the emergence of drug resistance progressively reduced the rate of virological remission to 39% at the fourth year of therapy. YMDD mutants explained the 75% of lamivudine resistances and were also selected very early in non-responders. Although the biochemical response is invariably lost within 29 months of the YMDD mutant's duration, the clinical outcome was benign despite severe postvirological breakthrough hepatitic flares in about 12% of cases.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Carcinoma Hepatocelular/etiologia , Avaliação de Medicamentos , Feminino , Seguimentos , Antígenos E da Hepatite B/análise , Hepatite B Crônica/imunologia , Humanos , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
11.
Ital J Gastroenterol ; 28(9): 499-504, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9131394

RESUMO

The high genetic variability of the 5' end of the envelope protein-coding region E2 (HVR1 E2) of Hepatitis C Virus (HCV) RNA has been suggested by many authors to play an important role in both virus persistence and outcome of liver disease. We studied the relations between HVR1 E2 variability and HCV genotypes, HCV-RNA levels and liver disease in 8 chronic HCV carriers (5 males and 3 females, median age 41 years, followed-up for a mean period of 3 years). Four were healthy HCV carriers with persistently normal ALT levels and normal liver histology and 4 patients with chronic liver disease. In each patient, the HVR1 E2 variability of 2 serum HCV-RNA isolates obtained at least 12 months apart were evaluated by direct sequencing. Nucleotide and amino acid homologies ranged between 97.6%-57.1% and 92.8%-25% in healthy carriers and 95.2%-55.9% and 89.3%-32.1% in patients, respectively. We did not observe any correlation between HVR1 E2 heterogeneity and HCV genotypes, viraemia levels, presence and extent of liver necroinflammation. Our findings suggest that HVR1 E2 heterogeneity has no direct implications in hepatitis, pathogenesis but it could play a major role in virus persistence.


Assuntos
Hepacivirus/genética , Hepatite C/virologia , RNA Viral/análise , Proteínas do Envelope Viral/genética , Adulto , Sequência de Bases , Doença Crônica , Primers do DNA/química , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Hepacivirus/imunologia , Hepatite C/patologia , Anticorpos Anti-Hepatite C/análise , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Viremia/virologia
12.
Physiol Behav ; 59(4-5): 915-20, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8778886

RESUMO

The purpose of the study reported here was to compare behavior, learning, and health problems in boys ages 6 to 12 with lower plasma phospholipid total omega-3 or total omega-6 fatty acid levels with those boys with higher levels of these fatty acids. A greater frequency of symptoms indicative of essential fatty acid deficiency was reported by the parents of subjects with lower plasma omega-3 or omega-6 fatty acid concentrations than those with higher levels. A greater number of behavior problems, assessed by the Conners' Rating Scale, temper tantrums, and sleep problems were reported in subjects with lower total omega-3 fatty acid concentrations. Additionally, more learning and health problems were found in subjects with lower total omega-3 fatty acid concentrations. (Only more colds and more antibiotic use were reported by those subjects with lower total omega-6 fatty acids). These findings are discussed in relation to recent findings for omega-3 experimentally deprived animals.


Assuntos
Transtornos do Comportamento Infantil/sangue , Ácidos Graxos Ômega-3/sangue , Saúde , Aprendizagem/fisiologia , Criança , Comportamento Infantil , Ácidos Graxos Ômega-6 , Ácidos Graxos Insaturados/sangue , Humanos , Masculino , Fosfolipídeos/sangue
13.
Hepatology ; 22(5): 1374-8, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7590650

RESUMO

Interferon alfa (IFN) therapy is efficacious in chronic viral hepatitides. It may, however, cause adverse immunologic reactions in patients with concomitant autoimmune phenomena. A minority of patients with chronic type C hepatitis have antibodies against liver and kidney microsomes (anti-LKM) in serum. We therefore carried out this study to find out whether IFN is safe and efficacious also in this subgroup. We treated 92 consecutive cases of chronic hepatitis C with IFN. Twelve patients had anti-LKM< and the remaining 80 tested negative to the anti-LKM. The hepatitis C virus (HCV) infection was diagnosed on the basis of positive anti-HCV and HCV-RNA tests. We compared the clinical and virological virological results of the therapy and the side effects found in the two groups. We found that the response to therapy and the outcome after 1 year of follow-up were similar. Treatment was discontinued in one anti-LKM-positive patient because of a drastic increase in ALT levels at the fourth month of therapy. No untoward effect was observed in the other cases. Hepatitis C patients with anti-LKM may be exposed to an increased risk of an adverse hepatitic reaction while being treated with IFN. However, we found that the extent of the risk was minimal compared with the expected benefits of the therapy. IFN is therefore recommended as the first therapy to choose in these patients. They must, however, be monitored more closely for possible liver dysfunction than the ordinary hepatitis C patient.


Assuntos
Antivirais/uso terapêutico , Autoanticorpos/análise , Hepatite C/imunologia , Hepatite C/terapia , Interferon-alfa/uso terapêutico , Microssomos Hepáticos/imunologia , Adulto , Idoso , Autoimunidade , Feminino , Humanos , Rim/imunologia , Rim/ultraestrutura , Masculino , Microssomos/imunologia , Pessoa de Meia-Idade , Resultado do Tratamento
14.
Am J Clin Nutr ; 62(4): 761-8, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7572706

RESUMO

Attention-deficit hyperactivity disorder (ADHD) is the term used to describe children who are inattentive, impulsive, and hyperactive. The cause is unknown and is thought to be multifactorial. Based on the work of others, we hypothesized that some children with ADHD have altered fatty acid metabolism. The present study found that 53 subjects with ADHD had significantly lower concentrations of key fatty acids in the plasma polar lipids (20:4n-6, 20:5n-3, and 22:6n-3) and in red blood cell total lipids (20:4n-6 and 22:4n-6) than did the 43 control subjects. Also, a subgroup of 21 subjects with ADHD exhibiting many symptoms of essential fatty acid (EFA) deficiency had significantly lower plasma concentrations of 20:4n-6 and 22:6n-3 than did 32 subjects with ADHD with few EFA-deficiency symptoms. The data are discussed with respect to cause, but the precise reason for lower fatty acid concentrations in some children with ADHD is not clear.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/metabolismo , Ácidos Graxos Essenciais/metabolismo , Estudos de Casos e Controles , Criança , Comportamento Infantil , Registros de Dieta , Ácidos Graxos Essenciais/sangue , Ácidos Graxos Essenciais/deficiência , Nível de Saúde , Humanos , Lipídeos/sangue , Masculino , Inquéritos e Questionários
15.
J Viral Hepat ; 2(4): 171-4, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7489343

RESUMO

Variations in the serum levels of hepatitis C virus (HCV) RNA. IgM antibody against the HCV 'core' structural protein (c22) and alanine amino-transferase (ALT) were measured in 23 patients with chronic hepatitis C who underwent therapy with interferon-alpha 2a (IFN alpha 2a). Low pretreatment levels of viraemia and undetectable IgM anti-core were significantly associated with a long-term response to treatment. In patients with hepatitis relapses after the end of treatment, HCV RNA levels increased before or at the same time as ALT in 29 out of 34 cases (85%). ALT flares occurred before or simultaneously with IgM anti-core elevations in 18 out of 20 cases (90%). Therefore, post-treatment hepatitis C exacerbations show the same sequence of events seen as in hepatitis B exacerbations (increases of viraemia followed by those of ALT and IgM anti-'core'). These findings underscore the diagnostic and prognostic usefulness of monitoring anti-HCV-positive patients with quantitative assays for HCV markers.


Assuntos
Alanina Transaminase/sangue , Hepacivirus/isolamento & purificação , Anticorpos Anti-Hepatite C/sangue , Hepatite C/imunologia , Hepatite C/virologia , RNA Viral/sangue , Biomarcadores , Doença Crônica , Hepacivirus/genética , Hepatite C/sangue , Hepatite C/terapia , Antígenos da Hepatite C , Humanos , Imunoglobulina M/sangue , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Proteínas Recombinantes , Recidiva , Proteínas do Core Viral/imunologia
16.
Int J Clin Lab Res ; 25(1): 35-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7787208

RESUMO

We designed a reverse transcription, polymerase chain reaction-based assay for serum hepatitis D virus RNA. Amplified hepatitis D virus cDNA was revealed by ethidium bromide staining, followed by blotting onto a nylon membrane and hybridization with a 32phosphorus-labelled oligonucleotide, or by a DNA enzyme immunoassay (DEIA) using a double stranded DNA-specific monoclonal antibody. The absolute sensitivity was expressed as number of hepatitis D virus RNA molecules, using a serum of known viral RNA concentration. Three sets of primers were used, encompassing the base positions 66-686 (variable rod-stabilizing region), 701-962 (conserved, viroid-like domain) and 886-1,333 (portion of the open reading frame 5 encoding for the carboxyterminus of the hepatitis D antigen) of the viral genome. The lower detection limits, after amplification of the three RNA portions, as assessed by ethidium bromide staining, were 7.5 x 10(6), 7.5 x 10(4) and 7.5 x 10(2) molecules of hepatitis D virus RNA per assay, respectively. The region encompassing bases 886-1,333 was chosen for blotting and hybridization to a radiolabelled oligonucleotide probe or for a capture-based DNA enzyme immunoassay, where the microplate was coated with this same probe. The two procedures showed comparable sensitivity, i.e., about 10 molecules of viral RNA per assay. The specificity of the assay was further on a panel of both anti-hepatitis D-positive and -negative sera. Amplification of serum hepatitis D virus RNA by reverse transcription/polymerase chain reaction followed by detection of the amplified cDNA by DNA enzyme immunoassay is a promising and feasible routine assay for detecting low amounts of circulating virions.


Assuntos
Vírus Delta da Hepatite/genética , Reação em Cadeia da Polimerase/métodos , RNA Viral/sangue , Animais , Sequência de Bases , Humanos , Dados de Sequência Molecular , Pan troglodytes
17.
Gastroenterology ; 107(2): 479-85, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8039625

RESUMO

BACKGROUND/AIMS: Prolonged interferon administration to patients with chronic hepatitis C, although increasing the sustained response rate, is poorly accepted and may favor drug resistance. A pulse-treatment schedule would be preferred for compliance and costs. METHODS: One hundred thirty-five patients with chronic hepatitis C received 6 MU units of interferon alfa-2a, three times weekly, continuously for 9 months (group 1: 66 patients) or for two 3-month cycles, separated by 6 months pause (group 2: 69 patients). RESULTS: At the end of therapy, 25 of 54 patients of group 1 (46.3%) and 28 of 60 of group 2 (46.7%) had normal serum aminotransferase levels. Six months after the end of treatment, sustained responders were still similar in the two groups (11 or 16.7% vs. 7 or 10.1%; NS). A loss of response before the end of therapy was seen in 10 patients of group 1 and 6 of group 2; interferon-neutralizing antibodies developed in 1 of 7 and 6 of 6 of such patients, respectively. CONCLUSIONS: The intermittent administration of interferon alfa-2a to patients with chronic hepatitis C shows a sustained response rate comparable with that achieved with continuous treatment at the same dosage. Hepatitis breakthroughs during pulse therapy appeared to be limited to interferon neutralizing antibodies, whereas a prolonged, continuous treatment is more likely to induce other forms of interferon resistance.


Assuntos
Hepatite C/terapia , Interferon-alfa/administração & dosagem , Adolescente , Adulto , Idoso , Anticorpos/metabolismo , Doença Crônica , Esquema de Medicação , Feminino , Seguimentos , Hepacivirus/genética , Hepatite C/imunologia , Hepatite C/microbiologia , Humanos , Interferon alfa-2 , Interferon-alfa/imunologia , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , Proteínas Recombinantes
19.
FEMS Microbiol Rev ; 14(3): 259-65, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7522024

RESUMO

Hepatitis C virus (HCV) infection is associated with a wide spectrum of liver disease ranging from asymptomatic carriage to severe forms of chronic hepatitis. HCV is not invariably pathogenic and genetic heterogeneity of HCV could be a major cause of such a variability. In clinical practice this means that presence and replication of the virus do not invariably imply a virus-induced liver damage. IgM antibodies that are the best diagnostic tools for the other forms of viral hepatitis are not sensitive and specific enough for hepatitis C, therefore we have to look for alternatives. Detection of anti-HCV does not help to distinguish past from present infections and only anti-HCV seroconversion in previously negative patients can indicate a recent HCV infection. However, the significant association between serum anti-C100-3 and HCV-RNA suggests that anti-HCV can be considered an indirect marker of HCV infectivity. In anti-HCV-negative infections and early acute hepatitis cases HCV-RNA detection will represent a valid diagnostic alternative. In patients undergoing antiviral therapy monitoring anti-HCV by immunoblotting assays and HCV-RNA by quantitative assays represent a valid tool to predict response that invariably has occurred in patients who had undetectable serum HCV-RNA and/or decreasing anti-HCV titres. Assays that detect multiple anti-HCV antibodies all together appear unsuitable for monitoring because they miss the disappearance of single antibodies. Anti-C22 appears the most frequent and earliest to be detected and usually it has the highest titre. Anti-C100 titres decrease earlier than anti-C33 and anti-C22 in patients with chronic HCV hepatitis who respond to antiviral therapy. The natural course of HCV infection appears to be characterized by three consecutive phases: disease, asymptomatic carrier and recovery. If transition from the first to the last occurs very slowly or the disease phase persists for years it may warrant in susceptible hosts severe forms of liver disease.


Assuntos
Hepatite C/complicações , Hepatopatias/etiologia , Hepacivirus/genética , Hepacivirus/imunologia , Anticorpos Anti-Hepatite/sangue , Hepatite C/imunologia , Hepatite C/transmissão , Anticorpos Anti-Hepatite C , Humanos , RNA Viral/análise
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