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1.
Emerg Microbes Infect ; 10(1): 929-938, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33913790

RESUMO

Context: Today, infective endocarditis (IE) caused by Enterococcus faecalis represents 10% of all IE and is marked by its difficult management and the frequency of relapses. Although the precise reasons for that remain to be elucidated, the evolution of the culprit strain under selective pressure through microdiversification could be, at least in part, involved. Material and methods: To further study the in situ genetic microdiversity and its possible phenotypic manifestations in E. faecalis IE, we sequenced and compared multiple isolates from the valves, blood culture and joint fluid of five patients who underwent valvular surgery. Growth rate and early biofilm production of selected isolates were also compared. Results: By sequencing a total of 58 E. faecalis genomes, we detected a considerable genomic microdiversity, not only among strains from different anatomical origins, but also between isolates from the same studied cardiac valves. Interestingly, deletions of thousands of bases including the well-known virulence factors ebpA/B/C, and srtC, as well as other large prophage sequences containing genes coding for proteins implicated in platelet binding (PlbA and PlbB) were evidenced. The study of mutations helped unveil common patterns in genes related to the cell cycle as well as central metabolism, suggesting an evolutionary convergence in these isolates. As expected, such modifications were associated with a significant impact on the in-vitro phenotypic heterogeneity, growth, and early biofilm production. Conclusion: Genome modifications associated with phenotypic variations may allow bacterial adaptation to both antibiotic and immune selective pressures, and thus promote relapses.


Assuntos
Endocardite Bacteriana/microbiologia , Enterococcus faecalis/classificação , Variação Genética , Infecções por Bactérias Gram-Positivas/microbiologia , Idoso , Idoso de 80 Anos ou mais , Códon sem Sentido , Enterococcus faecalis/genética , Enterococcus faecalis/isolamento & purificação , Feminino , Genoma Bacteriano , Valvas Cardíacas/microbiologia , Humanos , Masculino , Fenótipo , Deleção de Sequência , Sequenciamento Completo do Genoma
2.
Br J Dermatol ; 183(1): 105-113, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31610037

RESUMO

BACKGROUND: Necrotizing soft-tissue infections (NSTIs) are life threatening, requiring broad-spectrum antibiotics. Their aetiological diagnosis can be limited by poor performance of cultures and administration of antibiotics before surgery. OBJECTIVES: We aimed (i) to compare 16S-targeted metagenomics (TM) and unbiased semiquantitative panmicroorganism DNA- and RNA-based shotgun metagenomics (SM) with cultures, (ii) to identify patients who would best benefit from metagenomics approaches and (iii) to detect the microbial pathogens in surrounding non-necrotic 'healthy' tissues by SM-based methods. METHODS: A prospective observational study was performed to assess the analytical performance of standard cultures, TM and SM on tissues from 34 patients with NSTIs. Pathogen identification obtained with these three methods was compared. RESULTS: Thirty-four necrotic and 10 healthy tissues were collected from 34 patients. The performance of TM was inferior to that of the other methods (P < 0·05), whereas SM performed better than standard culture, although the result was not statistically significant (P = 0·08). SM was significantly more sensitive than TM for the detection of all bacteria (P = 0·02) and more sensitive than standard culture for the detection of anaerobic bacteria (P < 0·01). There was a strong correlation (r = 0·71, Spearman correlation coefficient) between the semiquantitative abundance of bacteria in the culture and the bacteria-to-human sequence ratio in SM. Low amounts of bacterial DNA were found in healthy tissues, suggesting a bacterial continuum between macroscopically 'healthy' and necrotic tissue. CONCLUSIONS: SM showed a significantly better ability to detect a broader range of pathogens than TM and identify strict anaerobes than standard culture. Patients with diabetes with NSTIs appeared to benefit most from SM. Finally, our results suggest a bacterial continuum between macroscopically 'healthy' non-necrotic areas and necrotic tissues. What's already known about this topic? Necrotizing soft-tissue infections (NSTIs) are characterized by rapidly progressive necrosis of subcutaneous tissues and high mortality, despite surgical debridement combined with broad-spectrum antibiotics. The spectrum of potentially involved pathogens is very large, and identification is often limited by the poor performance of standard cultures, which may be impaired by previous antibiotic intake. Metagenomics-based approaches show promise for better identification of the pathogens that cause these infections, but they have not been evaluated in this medical context. What does this study add? Shotgun metagenomics (SM) showed higher sensitivity than 16S rRNA gene sequencing and a better ability than culture to detect anaerobic bacteria. As a result, a significant proportion of infections with bacteria, such as Pasteurella multocida or Clostridium perfringens, were detected only by SM. SM bacterial quantification enabled better detection of low amounts of bacterial DNA from macroscopically 'healthy' tissue, suggesting a subclinical infectious extension. What is the translational message? The high analytical performance of SM shown in this study should allow its future implementation for the diagnosis of necrotizing fasciitis, complementing or replacing routine methods. The large amount of data, including additional information on antimicrobial resistance, virulence profiles and metabolic adaptation of the pathogens, will improve microbiological documentation. Our results will improve our understanding of infectious pathophysiology in the future, leading to potentially better medical care.


Assuntos
Fasciite Necrosante , Infecções dos Tecidos Moles , Bactérias/genética , Humanos , Metagenômica , RNA Ribossômico 16S/genética , Infecções dos Tecidos Moles/diagnóstico
3.
Clin Microbiol Infect ; 22(5): 459.e1-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26806260

RESUMO

Large-scale hepatitis C screening is required to prevent further spread of the infection, improve access to care in the context of new hepatitis C virus (HCV) drug regimens without interferon-alpha and subsequently reduce the risk of long-term complications of chronic liver disease. Rapid diagnostic tests (RDTs) represent an attractive alternative to enzyme immunoassay using blood from venepuncture. The aim of the present study was to prospectively assess the clinical performance of CE-marked RDTs detecting anti-HCV antibodies in fingerstick capillary whole blood and/or oral fluid. A total of 513 individuals, including 318 patients with chronic HCV infection, 25 patients with resolved HCV infection and 170 HCV-seronegative individuals, were prospectively enrolled. The specificity of RDTs with fingerstick whole blood varied from 98.8% to 100%. The clinical sensitivity was high for the OraQuick(®) and Toyo(®) tests (99.4% and 95.8%, respectively), but low for the Labmen(®) test (63.1%). The specificity and clinical sensitivity in crevicular fluid were both satisfactory for the OraQuick(®) test (100% and 97.6%, respectively). HCV antibody RDTs were easy and rapid to perform in the context of patient care. They were highly specific. Both the OraQuick(®) and Toyo(®) tests reached the expected level of performance for wide-scale use, with a performance advantage for the OraQuick(®) HCV test. RDTs appear to be a promising new tool for wide-scale screening of HCV infection in high-risk to medium-risk populations. Hence, careful assessment of the performance of HCV RDTs must be recommended before they can be implemented in clinical practice.


Assuntos
Cromatografia de Afinidade/métodos , Testes Diagnósticos de Rotina/métodos , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/análise , Anticorpos Anti-Hepatite C/sangue , Hepatite C Crônica/diagnóstico , Adolescente , Adulto , Idoso , Sangue/imunologia , Feminino , Líquido do Sulco Gengival/imunologia , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito , Estudos Prospectivos , Sensibilidade e Especificidade , Fatores de Tempo , Adulto Jovem
4.
J Clin Virol ; 69: 203-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26209408

RESUMO

BACKGROUND: The NS5A protein of the hepatitis C virus has been shown to be involved in the development of hepatocellular carcinoma. OBJECTIVES: In a French multicenter study, we investigated the clinical and epidemiological features of a new HCV genotype 1b strain bearing a wide insertion into the V3 domain. STUDY DESIGN: We studied NS5A gene sequences in 821 French patients infected with genotype 1b HCV. RESULTS: We identified an uncharacterized V3 insertion without ORF disruption in 3.05% of the HCV sequences. The insertion comprised 31 amino-acids for the majority of patients; 3 patients had 27 amino-acids insertions and 1 had a 12 amino-acids insertion. Sequence identity between the 31 amino-acids insertions and the V3 domain ranged from 48 to 96% with E-values above 4e(-5), thus illustrating sequence homology and a partial gene duplication event that to our knowledge has never been reported in HCV. Moreover we showed the presence of the duplication at the time of infection and its persistence at least during 12 years in the entire quasispecies. No association was found with extrahepatic diseases. Conversely, patients with cirrhosis were two times more likely to have HCV with this genetic characteristic (p=0.04). Moreover, its prevalence increased with liver disease severity (from 3.0% in patients without cirrhosis to 9.4% in patients with both cirrhosis and HCC, p for trend=0.045). CONCLUSIONS: We identified a duplicated V3 domain in the HCV-1b NS5A protein for the first time. The duplication may be associated with unfavorable evolution of liver disease including a possible involvement in liver carcinogenesis.


Assuntos
Carcinoma Hepatocelular/virologia , Hepacivirus/genética , Cirrose Hepática/virologia , Neoplasias Hepáticas/virologia , Mutagênese Insercional , Proteínas não Estruturais Virais/genética , Adulto , Idoso , Estudos Transversais , Feminino , França , Duplicação Gênica , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estrutura Terciária de Proteína , RNA Viral/análise , Análise de Sequência de RNA , Proteínas não Estruturais Virais/química
5.
J Viral Hepat ; 22(11): 890-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25818002

RESUMO

TNFα has been shown to play a role in hepatitis C virus (HCV)-induced insulin resistance (IR). Polymorphism of the IL28B gene that encodes IFN-lambda 3 may be associated with IR through modulation of TNFα. The aim of this study was to investigate the relationship between IL28B rs12979860 genotype, the level of TNFα activation and the degree of IR in patients with chronic hepatitis C. One hundred and thirty-three nondiabetic genotype 1 HCV-infected patients with biopsy proven noncirrhotic hepatitis C were investigated for IR (using HOMA index), IL28B rs12979860 genotype and fasting circulating levels of soluble receptor 1 of TNFα (sTNFR1) and adipokines: leptin, adiponectin and IL-6. The HOMA-IR was positively correlated with serum levels of leptin (r = 0.35, P < 0.0001) and sTNFR1 (r = 0.35, P < 0.0001) but not with IL-6 or adiponectin. IL28B rs12979860 CC genotype was observed in 35% patients. Genotype CC and nongenotype CC patients were similar in terms of HOMA-IR (means 1.6 ± 0.9 vs 1.7 ± 1.4) and had similar circulating levels of sTNFR1 and adipokines. Independent factors associated with IR were ferritin (OR = 1.002, P = 0.02), leptin (OR = 1.06, P = 0.02) and sTNFR1 (OR = 7.9, P = 0.04). This study suggests that in nondiabetic, noncirrhotic, HCV genotype 1-infected patients, there is no relationship between IL28B rs12979860 genotype and HOMA-IR or sTNFR1 level. HCV-related IR may be mediated through TNFα independent of IL28B genotype.


Assuntos
Hepatite C Crônica/complicações , Resistência à Insulina , Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/sangue , Adiponectina/sangue , Adulto , Idoso , Biomarcadores/sangue , Feminino , Hepatite C Crônica/patologia , Humanos , Interferons , Interleucina-6/sangue , Leptina/sangue , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Oncogene ; 32(39): 4683-93, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-23108410

RESUMO

Chronic infection by hepatitis C virus (HCV) is a major risk factor for the onset and development of hepatocellular carcinoma (HCC), although the underlying mechanisms are unclear. The c-Myc oncogene contributes to the genesis of many types of cancers, including HCC, partly via the induction of genetic damage and the inhibition of the cellular response to genotoxic stress. Here, we show a previously undiscovered mechanistic link between HCV infection and enhanced c-Myc expression. c-Myc expression was augmented in non-tumoral liver tissues from HCV-infected individuals with or without HCC and in hepatocyte cell lines harboring an HCV replicon and the infectious HCV strain JFH1. Increased c-Myc expression was confirmed in vivo in a transgenic murine model expressing the entire HCV open reading frame, demonstrating a direct role for HCV protein expression in c-Myc induction. Mechanistically, activation of Akt by the HCV non-structural protein NS5A, and the subsequent stabilization of the transcription factor ß-catenin, was demonstrated to be responsible for activation of the c-Myc promoter, and for increased c-Myc transcription. ß-Catenin-dependent c-Myc expression in this context led to increased production of reactive oxygen species, mitochondrial perturbation, enhanced DNA damage and aberrant cell-cycle arrest. Together, these data provide a novel insight into the mechanisms involved in HCV-associated HCCs, strongly suggesting that c-Myc has a crucial contributory role in this process.


Assuntos
Transformação Celular Viral/genética , Genes myc , Hepacivirus/fisiologia , Proteínas de Neoplasias/análise , Proteínas Proto-Oncogênicas c-myc/análise , Proteínas Proto-Oncogênicas c-myc/biossíntese , Proteínas não Estruturais Virais/fisiologia , beta Catenina/fisiologia , Adulto , Idoso , Animais , Carcinoma Hepatocelular/química , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/virologia , Núcleo Celular/química , Dano ao DNA , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Feminino , Hepacivirus/patogenicidade , Hepatócitos/química , Hepatócitos/ultraestrutura , Humanos , Neoplasias Hepáticas/química , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Fases de Leitura Aberta/genética , Estresse Oxidativo , Regiões Promotoras Genéticas , Mapeamento de Interação de Proteínas , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-akt/fisiologia , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/fisiologia , Interferência de RNA , RNA Viral/genética , Espécies Reativas de Oxigênio , Proteínas não Estruturais Virais/genética , beta Catenina/biossíntese , beta Catenina/genética
7.
Aliment Pharmacol Ther ; 34(6): 656-63, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21752038

RESUMO

BACKGROUND: Transient elastography measures liver stiffness, which correlates with the hepatic fibrosis stage and has excellent accuracy for the diagnosis of cirrhosis in patients with chronic hepatitis C. AIM: To assess prospectively the kinetics of liver stiffness in treated patients with chronic hepatitis C and compare them with the viral kinetics on treatment and with the final outcome of therapy. METHODS: 91 patients with chronic hepatitis C with significant fibrosis (>7.0kPa) at baseline were included. They received therapy with pegylated interferon-α and ribavirin. The kinetics of liver stiffness were characterized during therapy and thereafter by means of Fibroscan, and compared with the virological responses at weeks 4, 12, 24, end of treatment and 12 and 24weeks after. RESULTS: A significant liver stiffness decrease was observed during therapy, which continued after treatment only in patients who achieved a sustained virological response. In this group, the median intra-patient decrease relative to baseline at the end of follow-up was -3.4kPa, vs-1.8kPa in the patients who did not achieve an SVR. Similar dynamics were observed in cirrhotic and non-cirrhotic patients. In multivariate analysis, only the SVR was associated with long-term improvement of liver stiffness (odds ratio: 3.10; 95% confidence interval: 1.20-8.02, P=0.019). CONCLUSIONS: In patients with advanced fibrosis at the start of therapy, liver stiffness is significantly reduced during treatment, but improvement continues off treatment only in patients who achieve a sustained virological response. Liver stiffness assessment earlier than 6months after the end of therapy does not appear to be clinically meaningful.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/fisiopatologia , Interferon-alfa/uso terapêutico , Cirrose Hepática/fisiopatologia , Fígado/efeitos dos fármacos , Polietilenoglicóis/uso terapêutico , Adulto , Técnicas de Imagem por Elasticidade , Feminino , França , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Proteínas Recombinantes , Ribavirina/uso terapêutico
8.
Clin Microbiol Infect ; 17(2): 238-41, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20412189

RESUMO

Tracing risk factors for acquiring hepatitis C virus (HCV) in an HCV-infected patient, the only identified risk was working at the same butcher's counter of a supermarket as another HCV-infected patient, using a common ham cutting machine, with frequent bleeding hand injuries. A phylogenetic analysis showed a high percentage of nucleotide homology between the two patients' strains.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/diagnóstico , Hepatite C/transmissão , Doenças Profissionais/diagnóstico , Doenças Profissionais/virologia , Adulto , Feminino , Traumatismos da Mão , Humanos , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência , Proteínas do Envelope Viral/genética , Proteínas não Estruturais Virais/genética
9.
J Viral Hepat ; 14(1): 29-35, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17212641

RESUMO

Liver steatosis is highly prevalent in chronic hepatitis C virus (HCV) infection, especially in patients infected with genotype 3 virus, but its significance for the outcome of antiviral treatment is not fully understood. We have monitored steatosis in liver biopsies from 231 patients with chronic HCV infection who received pegylated recombinant interferon-alpha and ribavirin in a phase III study (DITTO trial). The degree of steatosis, along with relevant metabolic parameters, was correlated with the early disappearance of virus and with the final outcome of treatment. Our data suggest that the presence of steatosis impairs the early reduction of viral load during treatment in patients infected with HCV genotype 3 and non-3. Steatosis negatively affected the final outcome of treatment mainly in patients infected with HCV genotype non-3 virus. Based on these findings, we propose that interventions aiming at reducing hepatic steatosis prior to the onset of antiviral therapy may be of benefit to patients infected with HCV of the non-3 genotypes. Patients infected with genotype 3, on the other hand, should be offered early antiviral treatment.


Assuntos
Antivirais/uso terapêutico , Fígado Gorduroso/complicações , Hepacivirus/crescimento & desenvolvimento , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Biópsia , Fígado Gorduroso/virologia , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Estimativa de Kaplan-Meier , Cinética , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Proteínas Recombinantes , Resultado do Tratamento
10.
Gut ; 53(3): 420-4, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14960527

RESUMO

BACKGROUND AND AIM: Recent studies suggest that liver steatosis in chronic hepatitis C may be the expression of a direct cytopathic effect of hepatitis C virus (HCV), particularly in patients infected with genotype 3. To investigate this hypothesis, we studied the relationship between steatosis evolution and HCV clearance after antiviral treatment in patients with chronic hepatitis C and paired liver biopsies. METHODS: A total of 151 patients (37 with HCV genotype 3; 114 with HCV non-3 genotypes) were selected according to the following criteria: presence of steatosis at initial biopsy; no antiviral treatment prior to the first biopsy; antiviral treatment received between the two biopsies; body mass index (BMI) <28 kg/m(2); absence of excessive alcohol intake; no serum hepatitis B surface antigen or human immunodeficiency virus antibodies; and absence of diabetes mellitus. Evolution of steatosis was examined by comparing steatosis grades between the two biopsies. RESULTS: Twenty five patients (16.5%) were sustained virological responders (SVR) to antiviral treatment. Steatosis evolution after antiviral treatment was as follows: improvement in 36% of cases; stability in 51%; and worsening in 13%. Steatosis improvement was significantly more frequent in SVR than in non-responders (NR) (64% v 31%; p<0.004). This significant difference occurred in patients infected with genotype 3 (91% v 19%; p<0.0001) but not in those infected with non-3 genotypes (43% v 34%; NS). Among the 25 SVR, improvement in steatosis was significantly more frequent in patients infected with genotype 3 than in those infected with non-3 genotypes (91% v 43%; p<0.04) whereas in NR, improvement in steatosis did not differ between those infected with genotype 3 and non-3 genotypes (19% v 34%; NS). In multivariate analysis, four factors were independently associated with steatosis improvement: sustained virological response to antiviral therapy (odds ratio (OR) 6.06 (95% confidence interval (CI) 1.61-22.9); p = 0.01), severe steatosis (OR 5.50 (95% CI 1.54-19.6); p = 0.01), HCV genotype 3 (OR 2.90 (95% CI 0.85-10.0); p = 0.07), and BMI >25 kg/m(2) (OR 0.24 (95% CI 0.08-0.73); p = 0.02). CONCLUSIONS: Our results showed significant improvement in steatosis in patients infected with HCV genotype 3, who achieved sustained viral clearance. This provides further evidence for direct involvement of HCV genotype 3 in the pathogenesis of hepatic steatosis.


Assuntos
Antivirais/uso terapêutico , Fígado Gorduroso/virologia , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Adulto , Biópsia , Progressão da Doença , Fígado Gorduroso/patologia , Feminino , Genótipo , Hepacivirus/classificação , Hepatite C Crônica/complicações , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Resultado do Tratamento
11.
Neurology ; 60(5): 808-12, 2003 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-12629238

RESUMO

BACKGROUND: Hepatitis C virus (HCV)-associated neuropathy is usually associated with mixed cryoglobulinemia (MC) and vasculitis. MC may contain viral RNA, and tissues showing vasculitis may contain intracellular HCV. Local HCV replication remains to be evidenced. OBJECTIVE: To delineate the spectrum of HCV-associated neuropathy and to assess the presence of HCV in nerve and muscle tissues. METHODS: Thirty consecutive HCV-infected patients with peripheral neuropathy were included. Genomic and replicative strands of HCV RNA were detected in both nerve and muscle biopsy samples using distinctive reverse transcription nested PCR. RESULTS: Neuropathy was consistent with distal axonal polyneuropathy (DPN) in 25 of 30 patients, mononeuropathy multiplex (MM) in 3 of 30, and demyelinating polyneuropathy in 2 of 30. Pain was present in 18 of 30 patients and MC in 16 of 30. Biopsy showed inflammatory vascular lesions in 26 of 30 patients (87%), including necrotizing arteritis (6/30), small-vessel vasculitis (12/30) of either the lymphocytic (9/12) or the leukocytoclastic (3/12) type, and perivascular inflammatory infiltrates (8/30). All patients with necrotizing arteritis had DPN and positive MC detection. Both pain (p < 0.03) and positive MC detection (p < 0.01) were associated with the presence of vasculitis. Positive-strand genomic HCV RNA was detected in tissues of 10 of 30 patients (muscle 9, nerve 3). In contrast, negative-strand replicative RNA was never detected. Genomic RNA was found in nerve tissue samples showing vasculitis (necrotizing arteritis 2, small-vessel lymphocytic vasculitis 1). CONCLUSION: Painful DPN associated with MC and neuromuscular vasculitis is the most frequent type of HCV neuropathy. The usual detection of MC and the lack of local HCV replication indicate that HCV neuropathy results from virus-triggered immune-mediated mechanisms rather than direct nerve infection and in situ replication.


Assuntos
Hepatite C/complicações , Nervo Mediano/virologia , Músculo Esquelético/virologia , Doenças do Sistema Nervoso Periférico/virologia , RNA Viral/isolamento & purificação , Nervo Sural/virologia , Potenciais de Ação , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Crioglobulinemia/diagnóstico , Crioglobulinemia/virologia , Feminino , Humanos , Masculino , Nervo Mediano/patologia , Pessoa de Meia-Idade , Mononeuropatias/diagnóstico , Mononeuropatias/etiologia , Mononeuropatias/patologia , Músculo Esquelético/patologia , Condução Nervosa , Dor/etiologia , Doenças do Sistema Nervoso Periférico/diagnóstico , Polineuropatias/diagnóstico , Polineuropatias/etiologia , Polineuropatias/patologia , Púrpura/diagnóstico , Púrpura/etiologia , Estudos Retrospectivos , Nervo Sural/patologia , Vasculite/etiologia , Vasculite/patologia
12.
Gut ; 52(2): 288-92, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12524415

RESUMO

BACKGROUND AND AIMS: Steatosis, a frequent histological finding in patients with chronic hepatitis C (CHC), has been suggested to influence liver fibrosis progression. The aim of the present study was to evaluate in patients with CHC and paired liver biopsies the relationship between the evolution of steatosis and that of fibrosis between the two biopsies. METHODS: Ninety six patients were selected according to the following criteria: absence of treatment; absence of cirrhosis at initial biopsy; and serum hepatitis B surface antigen and human immunodeficiency virus antibody negativity. Degrees of necroinflammatory activity, fibrosis, and steatosis grades were assessed in the two biopsies. In addition to histological lesions, parameters studied included the source of infection, duration of infection, body mass index, alcohol intake, alanine aminotransferase levels, hepatitis C virus genotype, and viral load. RESULTS: The mean interval between the two biopsies was 48 (32) months. Steatosis was found in 54% of patients at first biopsy, and was severe in 9%. Worsening of steatosis was observed in 34% of patients, stability in 50%, and improvement in 16%. Worsening of steatosis was significantly associated with hepatic fibrosis progression in patients with (p=0.03) or without (p<0.03) steatosis at diagnosis. Overall, fibrosis progression was observed in 31% of patients and stability in 69%. In a univariate analysis, fibrosis progression was associated with male sex (p=0.05), worsening of histological activity (p=0.04), and worsening of steatosis (p=0.0003). In a multivariate analysis, the only factor independently associated with fibrosis progression was worsening of steatosis (worsening v improvement/stability: odds ratio 4.7 (95% confidence interval 1.3-10.8); p=0.0001). CONCLUSIONS: Our results suggest that in untreated patients with CHC and serial liver biopsies, fibrosis progression is strongly associated with worsening of steatosis.


Assuntos
Fígado Gorduroso/patologia , Hepatite C/patologia , Cirrose Hepática/patologia , Fígado/patologia , Adulto , Consumo de Bebidas Alcoólicas , Análise de Variância , Biópsia/métodos , Doença Crônica , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
13.
Gut ; 52(1): 126-9, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12477773

RESUMO

AIMS AND METHODS: To examine the association between smoking and histological liver lesions in chronic hepatitis C, we studied 244 consecutive patients (152 men, 92 women; mean age 45.9 (12.6) years) with histologically proven chronic hepatitis C. Daily tobacco consumption during the six months preceding liver biopsy was recorded as the number of cigarettes smoked daily. Total lifetime tobacco consumption was recorded as the number of cigarette packs smoked per year (packs-years). Liver biopsy specimens were graded for histological activity and fibrosis according to the METAVIR scoring system. RESULTS: The proportion of patients with moderate (A2) or marked (A3) activity increased gradually from 62.0% in non-smokers to 81.7% in patients who smoked more than 15 cigarettes per day (p<0.009). A similar relationship was observed with total lifetime tobacco consumption: 59.0% of patients who had never smoked had grade A2 or A3 disease activity compared with 84.6% of patients who smoked more than 20 packs per year (p<0.002). Multivariate analysis showed that age over 50 years (odds ratio (OR) 5.4), alcohol intake exceeding 20 g/day (OR 2.75), and tobacco consumption of more than 15 cigarettes/day (OR 3.6) were independently related to the histological activity score. No relationship was found between the severity of fibrosis and either daily tobacco consumption or total lifetime tobacco consumption. Multivariate analysis showed that only age over 50 years (OR 8.8), daily alcohol intake exceeding 30 g/day (OR 3.4), and histological activity score (OR 7.9) were independently related to the fibrosis score. CONCLUSION: This study suggests that smoking, independent of alcohol, could aggravate the histological activity of chronic hepatitis C and that patients with chronic hepatitis C virus infection should be advised to reduce or stop smoking.


Assuntos
Hepatite C Crônica/patologia , Fígado/patologia , Fumar/efeitos adversos , Adulto , Idoso , Consumo de Bebidas Alcoólicas , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Fatores de Tempo
14.
Transfusion ; 41(9): 1120-5, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11552068

RESUMO

BACKGROUND: The routes of transmission of human herpes virus 8 (HHV-8) remain unclear. In particular, HHV-8 transmission by blood components and organ transplantation is still debated and raises public health issues. The objective of this study was to determine the prevalence of anti-HHV-8 in selected populations of persons or patients with or without risk factors for the transmission of viral infections, in order to determine the routes of HHV-8 transmission. STUDY DESIGN AND METHODS: A total of 1431 persons or patients at low or high risk of sexually, blood-, or graft-transmitted viral infections were tested by means of a standardized immunofluorescence serologic assay detecting anti-HHV-8. RESULTS: The persons or patients could be classified into three distinct groups according to anti-HHV-8 prevalence: a low prevalence group (0.0% to 5.0%), including healthy blood donors, healthy pregnant women, multiply transfused patients with thalassemia major, and IV drug users; an intermediate prevalence group (5.0% to 20.0%), including organ donors, kidney transplant recipients, and multiply transfused patients with sickle cell disease; a high prevalence group (>20.0%), including HIV-negative persons at high risk of sexually-transmitted viral infections, and HIV-infected homosexual men and heterosexuals. CONCLUSION: The sexual route appears to be the main route of HHV-8 transmission; bloodborne transmission of HHV-8, if it exists, is rare. In contrast, organ transplantation recipients might be exposed to HHV-8 transmission by the transplanted organ, which raises the issue of systematic screening of organ donors.


Assuntos
Anticorpos Antivirais/análise , Transfusão de Sangue , Infecções por Herpesviridae/transmissão , Herpesvirus Humano 8/imunologia , Transplante de Órgãos , Comportamento Sexual , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estudos Soroepidemiológicos , Doadores de Tecidos
15.
J Virol ; 75(12): 5703-10, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11356980

RESUMO

Chronic hepatitis C virus (HCV) infection is a major cause of liver disease. The HCV polyprotein contains a hypervariable region (HVR1) located at the N terminus of the second envelope glycoprotein E2. The strong variability of this 27-amino-acid region is due to its apparent tolerance of amino acid substitutions together with strong selection pressures exerted by anti-HCV immune responses. No specific function has so far been attributed to HVR1. However, its presence at the surface of the viral particle suggests that it might be involved in viral entry. This would imply that HVR1 is not randomly variable. We sequenced 460 HVR1 clones isolated at various times from six HCV-infected patients receiving alpha interferon therapy (which exerts strong pressure towards quasispecies genetic evolution) and analyzed their amino acid sequences together with those of 1,382 nonredundant HVR1 sequences collected from the EMBL database. We found that (i) despite strong amino acid sequence variability related to strong pressures towards change, the chemicophysical properties and conformation of HVR1 were highly conserved, and (ii) HVR1 is a globally basic stretch, with the basic residues located at specific sequence positions. This conservation of positively charged residues indicates that HVR1 is involved in interactions with negatively charged molecules such as lipids, proteins, or glycosaminoglycans (GAGs). As with many other viruses, possible interaction with GAGs probably plays a role in host cell recognition and attachment.


Assuntos
Hepacivirus/fisiologia , Hepacivirus/patogenicidade , Proteínas do Envelope Viral/química , Proteínas Virais/química , Proteínas Virais/genética , Sequência de Aminoácidos , Sequência Conservada , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , Interferon gama/uso terapêutico , Dados de Sequência Molecular , Conformação Proteica , Análise de Sequência de DNA , Relação Estrutura-Atividade
16.
J Hepatol ; 31(6): 979-84, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10604569

RESUMO

BACKGROUND/AIMS: Liver iron accumulation has been described in patients with chronic active hepatitis (CAH) C, and could play a role in the course of liver disease and negatively influence the response to interferon. The aim of this study was to determine the prevalence and severity of liver iron accumulation in CAH C, to assess its relationship with the HFE C282Y and H63D mutations, and to study its interactions with hepatic histological lesions. METHODS: Two hundred and nine patients (131 men, 78 women, mean age 44.3+/-12.0 years) with CAH C, including 19 patients with cirrhosis (9.1%) were studied. A semiquantitative grading system from 0 to 3 was used for histological assessment of liver iron accumulation on Perls' staining. The HFE C282Y and H63D mutations were screened for by restriction enzyme analysis performed on PCR-amplified products. Histological scores of activity and fibrosis were determined according to a previously validated METAVIR score system. RESULTS: Liver iron accumulation was found in 88/209 patients (42.1%), and was generally mild. The C282Y and H63D allele frequencies were in 23 (11.0%), and 50 (23.9%), respectively. No association was found between the presence of liver iron accumulation and the detection of the C282Y and H63D mutations. A significant relationship was found between the severity of histological activity and liver iron accumulation of macrophagic or mixed (i.e. both macrophagic and hepatocytic) type (p = 0.04). Although the number of cirrhotic patients was small, cirrhosis was more frequently observed in patients with than without liver iron accumulation (17.2% vs. 3.3%, p = 0.004). CONCLUSIONS: Overall, these data suggest that the liver iron accumulation in patients with CAH C is significantly associated with histological activity and cirrhosis, whereas the two missense hemochromatosis gene mutations are not major determinants.


Assuntos
Antígenos HLA/genética , Hepatite C Crônica/genética , Hepatite C Crônica/metabolismo , Antígenos de Histocompatibilidade Classe I/genética , Ferro/metabolismo , Fígado/metabolismo , Proteínas de Membrana , Adulto , Feminino , Frequência do Gene , Hemocromatose/genética , Proteína da Hemocromatose , Hepatite C Crônica/patologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Prevalência
18.
Hepatology ; 30(3): 775-8, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10462385

RESUMO

It has been suggested that hepatitis C virus (HCV) infection could be associated with B-cell clonal expansion. The aim of this study was to analyze the relationship between lymphoproliferative disorders and HCV infection in liver transplant recipients. We studied 157 patients receiving a liver transplant between January 1989 and May 1997 with a follow-up longer than 3 months. The incidence of posttransplant lymphoproliferative disorders (PTLDs) was analyzed with reference to the indication for liver transplantation, the induction and maintenance immunosuppression, the incidence of acute rejection episodes, and Epstein-Barr virus (EBV) infection. Six PTLDs occurred after a median posttransplant follow-up of 7 months (3.8%). Four of the 6 PTLDs occurred among the 38 patients transplanted for HCV-related cirrhosis, and 2 PTLDs occurred in the 119 patients receiving a liver transplant for non-HCV liver diseases (10.5% vs. 1.7%, respectively; P =.03). The 4-year probability of PTLD was significantly higher in patients receiving a liver transplant for HCV-related cirrhosis than non-HCV liver diseases (12.3% vs. 2.2%, respectively; P =.015). Patients receiving a liver transplant for HCV-related cirrhosis were more likely to receive antithymocyte globulins (ATG). However, in patients treated with ATG, the 4-year probability of PTLD was higher among those patients receiving a liver transplant for HCV-related cirrhosis than for non-HCV liver diseases (27.1% vs. 6.4%, respectively; P =.08). EBV gene products were detected in tumor tissues in 3 of 4 patients with HCV-associated PTLD. Our data suggest that, in addition to EBV infection, 2 mutually nonexclusive factors, i.e., the use of ATG and HCV infection, could play a role in the occurrence of PTLD after a liver transplant for HCV-related cirrhosis.


Assuntos
Hepatite C/complicações , Transplante de Fígado/efeitos adversos , Transtornos Linfoproliferativos/etiologia , Adulto , Idoso , Linfócitos B/imunologia , Feminino , Herpesvirus Humano 4/isolamento & purificação , Humanos , Ativação Linfocitária , Transtornos Linfoproliferativos/virologia , Masculino , Pessoa de Meia-Idade
19.
J Virol ; 73(8): 6490-9, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10400744

RESUMO

Sustained hepatitis C virus (HCV) RNA clearance is achieved in 8 to 12% of patients with chronic HCV infection treated with alpha interferon (IFN-alpha) at the approved dose of 3 MU three times a week for 6 months and in about 25% of those receiving this treatment for 12 months. We used single-strand conformation polymorphism analysis combined with cloning and sequencing strategies to characterize the genetic evolution of HCV second envelope gene hypervariable region 1 (HVR1) quasispecies during and after IFN therapy in patients who failed to clear HCV RNA. Sustained HCV RNA clearance was achieved in 6% of patients. Profound changes in HVR1 quasispecies major variants were estimated to occur in 70% of the patients during and after therapy. These changes were evolutionary and were characterized by shifts in the virus population, related to selection and subsequent diversification of minor pretreatment variants. The quasispecies changes appeared to be induced by changes in the host environment likely resulting from the IFN-induced enhancement and post-IFN attenuation of neutralizing and possibly cytotoxic responses against HVR1. The remaining patients had no apparent changes in HVR1 quasispecies major variants, suggesting selection of major pretreatment variants, but some changes were observed in other genomic regions. We conclude that IFN-alpha administration and withdrawal profoundly alters the nature of circulating HCV quasispecies, owing to profound changes in virus-host interactions, in patients in whom sustained HCV RNA clearance fails to occur. These changes are associated with profound alterations of the natural outcome of HCV-related liver disease, raising the hypothesis of a causal relationship.


Assuntos
Antivirais/uso terapêutico , Evolução Molecular , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Interferon-alfa/uso terapêutico , Proteínas do Envelope Viral/genética , Adolescente , Adulto , Idoso , Alanina Transaminase/metabolismo , Feminino , Variação Genética , Hepacivirus/classificação , Hepatite C Crônica/metabolismo , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Filogenia , RNA Viral , Proteínas Recombinantes
20.
J Virol Methods ; 80(1): 33-44, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10403674

RESUMO

This study was undertaken in order to determine whether screening of viremic blood donations by testing of pooled donor samples could constitute a technically feasible transfusional safety measure. A pilot study of real-time simulation, on a day-to-day basis, of screening of three viral genomes (hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV)) was conducted by five French Blood Centers on plasma samples collected from blood donors and studied within undiluted samples and within sample pools of various sizes. This study was carried out within time conditions compatible with the release of platelets. For the detection of HCV and HIV genomes, the five laboratories achieved a sensitivity that decreased with the size of the sample pool. Four were successful in detecting all undiluted samples. In the 1/10 diluted samples, four failed to detect one HIV or HCV sample. In the 1/100 diluted samples, all laboratories failed to detect one or more HIV or HCV samples. For HBV genome, no participating laboratories detected all of the samples of the panel, even undiluted samples, and the sample pooling considerably affected sensitivity. The improvement and standardization of assays needs to be attained, and training of laboratories appears to be a step crucial for routine screening of viral genomes in blood donations.


Assuntos
Doadores de Sangue , Genoma Viral , HIV/isolamento & purificação , Hepacivirus/isolamento & purificação , Vírus da Hepatite B/isolamento & purificação , Sangue/virologia , HIV/genética , Hepacivirus/genética , Vírus da Hepatite B/genética , Humanos , Programas de Rastreamento/métodos , Projetos Piloto , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Fatores de Tempo , Carga Viral
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