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1.
Clin Microbiol Infect ; 26(8): 1094.e1-1094.e5, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32450255

RESUMO

OBJECTIVES: To detect possible severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA contamination of inanimate surfaces in areas at high risk of aerosol formation by patients with coronavirus disease 2019 (COVID-19). METHODS: Sampling was performed in the emergency unit and the sub-intensive care ward. SARS-CoV-2 RNA was extracted from swabbed surfaces and objects and subjected to real-time RT-PCR targeting RNA-dependent RNA polymerase and E genes. Virus isolation from positive samples was attempted in vitro on Vero E6 cells. RESULTS: Twenty-six samples were collected and only two were positive for low-level SARS-CoV-2 RNA, both collected on the external surface of continuous positive airway pressure helmets. All transport media were inoculated onto susceptible cells, but none induced a cytopathic effect on day 7 of culture. CONCLUSIONS: Even though daily contact with inanimate surfaces and patient fomites in contaminated areas may be a medium of infection, our data obtained in real-life conditions suggest that it might be less extensive than hitherto recognized.


Assuntos
Betacoronavirus/crescimento & desenvolvimento , Fômites/virologia , RNA Polimerase Dependente de RNA/genética , Proteínas do Envelope Viral/genética , Animais , Betacoronavirus/genética , Chlorocebus aethiops , Proteínas do Envelope de Coronavírus , Contaminação de Equipamentos , Humanos , Unidades de Terapia Intensiva , Viabilidade Microbiana , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2 , Células Vero , Proteínas Virais/genética
3.
J Viral Hepat ; 25(4): 320-328, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29112304

RESUMO

To examine mid-term benefits on hepatic complications, extrahepatic clinical syndromes and quality of life associated with HCV cure; to review the few safety issues linked to oral direct-acting antivirals (DAAs); and to discuss the potential population benefits of reducing the burden of HCV infection. DAAs cure HCV infection in more than 95% of patients. The halting of liver inflammation and fibrosis progression translates into both hepatic and extrahepatic benefits and reduces the need for liver transplantation. A reduction in the frequency of extrahepatic manifestations such as mixed cryoglobulinaemia and vasculitis and improvements in quality of life and fatigue have also been described. A few safety issues linked to DAAs such as the potential recurrence of aggressive HCC, the flares of hepatitis B virus in patients with overt or occult HBV infection are been discussed. Curing HCV infection also has a high potential to reduce the burden of HCV infection at the population level. With widespread scaling up of HCV treatment, several modeling studies suggest that major reductions in HCV prevalence and incidence are possible, and that elimination of viral hepatitis is an achievable target by 2030.


Assuntos
Antivirais/efeitos adversos , Antivirais/uso terapêutico , Hepatite B/patologia , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Exacerbação dos Sintomas , Vírus da Hepatite B , Humanos , Recidiva
4.
Clin Microbiol Infect ; 21(11): 1027-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26166544

RESUMO

The prevalence and management of chronic hepatitis B virus (HBV) infection differ among European countries. The availability and reimbursement of diagnostics and drugs may also vary, determining distinct treatment outcomes. Herein, we analyse differences in medical facilities for the care of patients with chronic HBV infection across Europe. A survey was sent to the members of the ESCMID Study Group for Viral Hepatitis, all of whom are experts in chronic HBV infection management. The comprehensive survey asked questions regarding hepatitis B surface antigen (HBsAg) prevalence, the availability of diagnostics and drugs marketed, and distinct clinical practice behaviours in the management of chronic HBV infection. World Bank data were used to assess the economic status of the countries. With 16 expert physicians responding (69%), the HBsAg prevalence rates were <1% in France, Hungary, Italy, The Netherlands, Portugal, Spain, and the UK, intermediate (1-5%) in Turkey, Romania, and Serbia, and high (>5%) in Albania and Iran. Regarding the availability and reimbursement of HBV diagnostics (HBV DNA and liver stiffness measurement), HBV drugs (interferon, lamivudine, tenofovir, and entecavir), HBV prophylaxis, and duration of HBeAg-positive and HBeAg-negative HBV infection, the majority of high-income and middle-income countries had no restrictions; Albania, Iran and Serbia had several restrictions in diagnostics and HBV drugs. The countries in the high-income group were also the ones with no restrictions in medical facilities, whereas the upper-middle-income countries had some restrictions. The prevalence of chronic HBV infection is much higher in southern and eastern than in western European countries. Despite the availability of European guidelines, policies for diagnostics and treatment vary significantly across European countries.


Assuntos
Acessibilidade aos Serviços de Saúde , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Antivirais/uso terapêutico , Testes Diagnósticos de Rotina/métodos , Testes Diagnósticos de Rotina/estatística & dados numéricos , Uso de Medicamentos , Europa (Continente)/epidemiologia , Feminino , Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/epidemiologia , Humanos , Masculino , Estudos Soroepidemiológicos , Inquéritos e Questionários
5.
J Viral Hepat ; 22(4): 391-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25258145

RESUMO

Chronic hepatitis C virus (HCV) infection is characterized by persistent B-cell activation, with enhanced differentiation and reduced proliferative ability. To assess the possible role of HCV in altering B-cell subset distribution, we examined ex vivo frequencies and B-cell inhibitory receptor expression in 37 chronic HCV-infected patients and 25 healthy donors (HD). In addition, we determined whether short-term exposure to culture-derived HCV (HCVcc) resulted in B-cell subset skewing and/or activation. There was a statistically significant increase in the frequencies of immature transitional, activated memory and tissue-like memory (TLM) B cells in HCV-infected patients compared with HD. We also found that the frequency of memory B cells correlated with serum HCV RNA levels. The proportion of B cells expressing the marker of exhaustion Fc receptor-like 4 (FcRL4) was generally low even though significantly higher in the patients' memory B-cell compartment compared with HD, and a positive correlation was found between the frequencies of the patients' TLM FcRL4+ B cells and serum alanine aminotransferase and histological activity index at liver biopsy. Exposure to cell-free HCVcc in vitro did not result in B-cell skewing but induced significant activation of naïve, TLM and resting memory B cells in HCV-infected patients but not in HD, in whom cell-associated virus was an absolute requirement for activation of memory B cells. These findings provide corroborative evidence in favour of significant B-cell subset skewing in chronic HCV infection and in addition show that expression of exhaustion markers in selected B-cell subsets does not impair virus-induced B-cell activation.


Assuntos
Linfócitos B/imunologia , Hepatite C Crônica/imunologia , Subpopulações de Linfócitos/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/sangue , Linfócitos B/química , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Memória Imunológica , Imunofenotipagem , Fígado/patologia , Subpopulações de Linfócitos/química , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Receptores Fc/análise , Carga Viral
6.
J Viral Hepat ; 15(1): 66-70, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18088247

RESUMO

Monitoring of HCV-RNA in blood during antiviral therapy is performed mostly by commercially available reverse transcription polymerase chain reaction-based (RT-PCR) assays, with a lower detection limit of 30-50 IU/mL of HCV-RNA. Use of different tests in the pivotal trials of combination therapy has generated some discordance, in terms of predictive value of the early virological response (EVR). To evaluate whether the use of a more sensitive test, as a qualitative assay based on transcription mediated amplification (TMA) with a lower detection limit of 5-10 IU/mL of HCV-RNA, may obtain a better prediction of EVR and of the ultimate virological outcome, we retrospectively evaluated serial samples from 108 naïve patients with HCV genotype 1 chronic hepatitis, treated with pegylated alpha2b interferon plus ribavirin for 48 weeks and with a 24 weeks stopping rule. Serum samples of patients, obtained during treatment at weeks 4, 12, 24 and 48 and after treatment at week 24, were evaluated by TMA. Comparison of the RT-PCR and TMA assays for the qualitative detection of HCV-RNA showed no significant differences in performance when these tests were used at the end of the treatment period for assessing patients without an on-treatment virological response and those who eventually obtain a sustained virological response. Our results show instead that the use of TMA assay to detect HCV-RNA at 12 and 24 weeks of the combination therapy is more effective than RT-PCR in identifying patients with the highest probability of sustained HCV-RNA clearance.


Assuntos
Quimioterapia Combinada , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Técnicas de Amplificação de Ácido Nucleico/métodos , RNA Viral/isolamento & purificação , Transcrição Gênica , Antivirais/uso terapêutico , Feminino , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Polietilenoglicóis , Valor Preditivo dos Testes , RNA Viral/sangue , RNA Viral/genética , Proteínas Recombinantes , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Ribavirina/uso terapêutico , Sensibilidade e Especificidade , Resultado do Tratamento
7.
Gut ; 53(11): 1673-81, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15479691

RESUMO

BACKGROUND/AIMS: Hepatitis C virus (HCV) infection results in a high frequency of chronic disease. The aim of this study was to identify early prognostic markers of disease resolution by performing a comprehensive analysis of viral and host factors during the natural course of acute HCV infection. METHODS: The clinical course of acute hepatitis C was determined in 34 consecutive patients. Epidemiological and virological parameters, as well as cell mediated immunity (CMI) and distribution of human leukocyte antigens (HLA) alleles were analysed. RESULTS: Ten out of 34 patients experienced self-limiting infection, with most resolving patients showing fast kinetics of viral clearance: at least one negative HCV RNA test during this phase predicted a favourable outcome. Among other clinical epidemiological parameters measured, the self-limiting course was significantly associated with higher median peak bilirubin levels at the onset of disease, and with the female sex, but only the latter parameter was independently associated after multivariate analysis. No significant differences between self-limiting or chronic course were observed for the distribution of DRB1 and DQB1 alleles. HCV specific T cell response was more frequently detected during acute HCV infection, than in patients with chronic HCV disease. A significantly broader T cell response was found in patients with self-limiting infection than in those with chronic evolving acute hepatitis C. CONCLUSION: The results suggest that host related factors, in particular sex and CMI, play a crucial role in the spontaneous clearance of this virus. Most importantly, a negative HCV RNA test and broad CMI within the first month after onset of the symptoms represent very efficacious predictors of viral clearance and could thus be used as criteria in selecting candidates for early antiviral treatment.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/imunologia , Linfócitos T/imunologia , Adulto , Alelos , Feminino , Seguimentos , Genes MHC da Classe II , Predisposição Genética para Doença , Antígenos HLA-DR/genética , Cadeias HLA-DRB1 , Hepatite C/genética , Hepatite C/virologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C Crônica/genética , Hepatite C Crônica/imunologia , Teste de Histocompatibilidade , Humanos , Imunidade Celular , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Viral/sangue , Remissão Espontânea
9.
J Biol Regul Homeost Agents ; 17(2): 128-32, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14518710

RESUMO

Hepatitis C virus (HCV) is a common transmissible agent responsible for a significant proportion of chronic liver disease, cirrhosis and hepatocellular carcinoma worldwide. The natural history of acute HCV infection is characterized by a high rate of progression to persistent infection. The resulting chronic liver disease is dependent upon a delicate balance of host, viral and environmental factors which may significantly influence its clinical outcome.


Assuntos
Hepacivirus , Hepatite C/etiologia , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/imunologia , Progressão da Doença , Variação Genética , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/imunologia , Hepatite C Crônica/etiologia , Hepatite C Crônica/imunologia , Humanos , Cirrose Hepática/etiologia , Cirrose Hepática/imunologia , Fatores de Risco
10.
Mol Immunol ; 38(6): 485-92, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11741698

RESUMO

Hepatitis C virus (HCV) is a major cause worldwide of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma, and the development of an effective vaccine represents a high priority goal. The hyper variable region 1 (HVR1) of the second envelope protein (E2) of HCV contains a principal neutralizing determinant, but it is highly variable among different isolates and it is involved in the escape from host immune response. To be effective, a vaccine should elicit a cross-reacting humoral response against the majority of viral variants. We show that it is possible to achieve a broadly cross-reactive immune response in rabbits by immunization with mimotopes of the HVR1, selected from a specialized phage library using HCV patients' sera. Some of the cross-reacting anti-mimotope antibodies elicited in rabbits, recognize discontinuous epitopes in a manner similar to those induced by the virus in infected patients.


Assuntos
Anticorpos Anti-Hepatite C/imunologia , Hepatite C Crônica/imunologia , Proteínas do Envelope Viral/imunologia , Vacinas contra Hepatite Viral/imunologia , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Especificidade de Anticorpos , Reações Cruzadas , Feminino , Hepatite C Crônica/prevenção & controle , Humanos , Epitopos Imunodominantes/genética , Epitopos Imunodominantes/imunologia , Dados de Sequência Molecular , Biblioteca de Peptídeos , Coelhos , Proteínas do Envelope Viral/genética
12.
Antiviral Res ; 52(2): 153-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11672825

RESUMO

The hypervariable region 1 (HVR1) of the E2 protein of hepatitis C virus (HCV) is highly heterogeneous and is responsible for significant inter- and intra-individual variation of the infecting virus, which may represent an important pathogenetic mechanism leading to escape and persistent infection. Moreover, a binding site for neutralizing antibodies (Ab) has been allegedly identified in this region. Prospective studies of serological responses to synthetic oligopeptides derived from HVR1 sequences of patients with acute and chronic HCV infection showed extensive serological cross-reactivity for unrelated HVR1 peptides in the majority of the patients. A significant correlation was found between HVR1 sequence variation, and intensity, and cross-reactivity of humoral immune responses providing strong evidence in support of the contention that HCV variant selection is driven by the host immune pressure. Monoclonal Ab (mAb) generated following immunization of mice with peptides derived from natural HVR1 sequences also showed cross-reactivity for several HVR1 sequences attesting to the existence of conserved amino acid motifs among different variants. These findings suggest that it is possible to induce a broadly cross-reactive immune response to HVR1 and that this mechanism can be used to generate protective immunity for a large repertoire of HCV variants.


Assuntos
Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/imunologia , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Reações Cruzadas , Mapeamento de Epitopos , Epitopos de Linfócito B/imunologia , Anticorpos Anti-Hepatite C/sangue , Humanos , Estrutura Terciária de Proteína
13.
J Immunol ; 167(7): 3878-86, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11564805

RESUMO

The hypervariable region 1 (HVR1) of the E2 protein of hepatitis C virus (HCV) is a highly heterogeneous sequence that is promiscuously recognized by human sera via binding to amino acid residues with conserved physicochemical properties. We generated a panel of mAbs from mice immunized with HVR1 surrogate peptides (mimotopes) affinity-selected with sera from HCV-infected patients from a phage display library. A high number of specific clones was obtained after immunization with a pool of nine mimotopes, and the resulting mAbs were shown to recognize several 16- and 27-mer peptides derived from natural HVR1 sequences isolated from patients with acute and chronic HCV infection, suggesting that HVR1 mimotopes were efficient antigenic and immunogenic mimics of naturally occurring HCV variants. Moreover, most mAbs were shown to bind HVR1 in the context of a complete soluble form of the E2 glycoprotein, indicating recognition of correctly folded HVR1. In addition, a highly promiscuous mAb was able to specifically capture bona fide viral particles (circulating HCV RNA) as well as rHCV-like particles assembled in insect cells expressing structural viral polypeptides derived from an HCV 1a isolate. These findings demonstrate that it is possible to induce a broadly cross-reactive clonal Ab response to multiple HCV variants. In consideration of the potentially important role of HVR1 in virus binding to cellular receptor(s), such a mechanism could be exploited for induction of neutralizing Abs specific for a large repertoire of viral variants.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Hepacivirus/imunologia , Proteínas do Envelope Viral/imunologia , Vírion/imunologia , Especificidade de Anticorpos , Antígenos Virais/química , Reações Cruzadas , Mapeamento de Epitopos , Hepacivirus/isolamento & purificação , Hepatite C/imunologia , Hepatite C/virologia , Humanos , Peptídeos/imunologia , Dobramento de Proteína , Proteínas do Envelope Viral/química
14.
Clin Infect Dis ; 33(1): 70-5, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11389497

RESUMO

Because hepatitis C virus (HCV) genotypes have raised considerable interest as variables that influence chronic hepatitis C progression, a case-control study was conducted to estimate their effects on patients with cirrhosis. Case patients (n = 46) had tested positive for anti-HCV antibody and HCV RNA and were residents of the study area who had cirrhosis recently diagnosed. Controls (n = 138) were drawn randomly from a residents' cohort from the same area. Demographic and other information were recorded. Presence of HCV infection, presence of HCV RNA, and HCV genotypes were assessed. Crude, stratified, and logistic regression analyses were performed. HCV genotype 2a/c occurred in 84 controls (60.9%) and 9 case patients (19.6%); HCV genotype 1b was found in 45 controls (32.6%) and 34 case patients (73.9%). HCV 1b genotype showed an independent effect on the risk of cirrhosis (odds ratio, 7.49; 95% confidence interval, 3.15--17.81). No significant effects related to other variables were observed. These results indicate that the genetic diversity of HCV phylogenetic variants may explain differences in biological behaviors.


Assuntos
Fibrose/virologia , Hepacivirus/genética , Hepatite C Crônica/virologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Fibrose/diagnóstico , Genótipo , Hepacivirus/classificação , Anticorpos Anti-Hepatite C/sangue , Hepatite C Crônica/complicações , Humanos , Itália , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Fatores de Risco
17.
Int Rev Immunol ; 20(2): 289-300, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11878771

RESUMO

Hepatitis C Virus (HCV) is a major cause of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma, worldwide, and the development of an effective vaccine represents a high priority goal. The Hyper Variable Region 1 (HVR1) of the second Envelope protein (E2) of HCV contains a principal neutralizing determinant, but it is highly variable among different isolates and it is involved in the escape from host immune response. Thus, to be effective, a vaccine should elicit a cross-reacting humoral response against the majority of viral variants. We show that it is possible to achieve a broadly cross-reactive immune response in rabbits by immunization with mimotopes of the HVR1. selected from a specialized phage library using HCV patients' sera. At least some of the cross-reacting anti-mimotope antibodies, elicited in rabbits, recognize discontinuous epitopes in a manner similar to those induced by the virus in infected patients.


Assuntos
Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/biossíntese , Sequência de Aminoácidos , Animais , Variação Antigênica , Reações Cruzadas , Mapeamento de Epitopos , Hepacivirus/genética , Humanos , Imunização , Mimetismo Molecular , Dados de Sequência Molecular , Coelhos , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia
19.
Hepatology ; 30(2): 537-45, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10421665

RESUMO

Sequence heterogeneity of hepatitis C virus (HCV) is unevenly distributed along the genome, and maximal variation is confined to a short sequence of the HCV second envelope glycoprotein (E2), designated hypervariable region 1 (HVR1), whose biological function is still undefined. We prospectively studied serological responses to synthetic oligopeptides derived from HVR1 sequences of patients with acute and chronic HCV infection obtained at baseline and after a defined follow-up period. Extensive serological cross-reactivity for unrelated HVR1 peptides was observed in the majority of the patients. Antibody response was restricted to the IgG1 isotype and was focused on the carboxyterminal end of the HVR1 region. Cross-reactive antibodies could be readily elicited following immunization of mice with multiple antigenic peptides carrying HVR1 sequences derived from our patients. The vigor and heterogeneity of cross-reactive antibody responses were significantly higher in patients with chronic hepatitis compared with those with acute hepatitis and in patients infected with HCV type 2 compared with patients infected with other viral genotypes (predominantly type 1), which suggest that higher time-related HVR1 sequence diversification previously described for type 2 may result from immune selection. The finding of a statistically significant correlation between HVR1 sequence variation, and intensity, and cross-reactivity of humoral immune responses provided stronger evidence in support of the contention that HCV variant selection is driven by the host's immune pressure.


Assuntos
Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Proteínas do Envelope Viral/imunologia , Adolescente , Adulto , Idoso , Sequência de Aminoácidos , Criança , Reações Cruzadas , Mapeamento de Epitopos , Feminino , Hepatite C/imunologia , Humanos , Imunização , Imunoglobulina G/sangue , Imunoglobulina G/classificação , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteínas do Envelope Viral/química
20.
J Clin Microbiol ; 37(7): 2371-2, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10364620

RESUMO

In a cohort of subjects from Italy, anti-hepatitis C virus (HCV) and HCV RNA [HCV(+) subgroup] prevalences were 24.6 and 79.6%, respectively. HCV types 1b and 2a/c accounted for 95% of infections. Adjusted alanine aminotransferase levels were higher in males than in females and in RNA-positive subjects than in RNA-negative subjects regardless of HCV type. Genotype distribution was unrelated to demographic variables.


Assuntos
Hepacivirus/genética , Hepatite C/epidemiologia , Alanina Transaminase/sangue , Estudos de Coortes , Demografia , Feminino , Genótipo , Hepacivirus/classificação , Hepacivirus/isolamento & purificação , Hepatite C/sangue , Humanos , Itália/epidemiologia , Masculino , Epidemiologia Molecular , RNA Viral/sangue , Sistema de Registros , Sorotipagem , Fatores Sexuais
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