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1.
BMC Public Health ; 18(1): 409, 2018 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-29587697

RESUMEN

BACKGROUND: We investigated the association between self-reported skirt size (SS) and change in SS, and incidence of chronic liver disease (CLD) in a prospective cohort study of women recruited to the UKCTOCS trial. METHODS: Women recruited to UKCTOCS in England without documented CLD self-reported their current UK SS during trial participation and were asked to recall their SS when aged in 20s (via completion of a questionnaire 3-5 years after recruitment). Participants were followed up via electronic health record linkage and hazard ratios (HR) calculated for incident liver-related events (LRE). RESULTS: Three hundred twenty-two (0.3%) of 94,124 women experienced a first LRE. Compared to SS ≤ 16, rates of LRE were higher in the SS ≥ 18 groups (both when aged in 20s and at questionnaire completion). Event rates were higher if there was no change in SS or an increase in SS, compared to a decrease in SS. In the models adjusted for potential confounders, HRs for LRE were higher in the groups of women reporting SS ≥ 18 both when aged in 20s (HR = 1.39 (95% CI; 0.87-2.23)) and at questionnaire completion (HR = 1.37 (95% CI; 1.07-1.75)). Compared to a decrease in SS, HRs were higher in the no change (HR = 1.78 (95% CI; 0.95-3.34)) and increase (HR = 1.80 (95% CI; 1.01-3.21)) groups. CONCLUSION: CLD is associated with high SS and an increase in SS over time. These data suggest SS can be used in simple public health messages about communicating the risk of liver disease. TRIAL REGISTRATION: UKCTOCS is registered as an International Standard Randomised Controlled Trial, number ISRCTN22488978 . Registered 06/04/2000.


Asunto(s)
Hepatopatías/epidemiología , Posmenopausia , Circunferencia de la Cintura , Anciano , Enfermedad Crónica , Detección Precoz del Cáncer , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/diagnóstico , Estudios Prospectivos , Autoinforme , Reino Unido/epidemiología
2.
Br J Dermatol ; 171(2): 267-73, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24942271

RESUMEN

BACKGROUND: Methotrexate is a cost-effective systemic treatment for moderate-to-severe psoriasis, but the perceived risk of associated liver fibrosis prevents optimal use. Procollagen III aminoterminal propeptide (PIIINP) is a widely adopted noninvasive biomarker of liver fibrosis; however, its clinical utility is narrow owing to limited evidence of performance and the need for serial measurement. The Enhanced Liver Fibrosis (ELF) assay is a validated biomarker of liver fibrosis. OBJECTIVES: To evaluate the diagnostic accuracy of the ELF test compared with PIIINP for the diagnosis of liver fibrosis in a cohort of patients with psoriasis treated with methotrexate. METHODS: A retrospective cohort study comparing the diagnostic accuracy of PIIINP and ELF in detecting liver fibrosis in patients treated with methotrexate. Liver biopsy was the reference standard. RESULTS: Twenty-seven patients were identified and included in the study. The diagnostic accuracies [area under the receiver operating curve (AUROC)] of serial PIIINP and serial ELF were 0·589 [95% confidence interval (CI) 0·379-0·800] and 0·643 (95% CI 0·391-0·895), respectively, for mild fibrosis; and 0·576 (95% CI 0·237-0·916) and 0·674 (95% CI 0·421-0·927) for at least moderate fibrosis. The AUROC values for single PIIINP and single ELF were 0·582 (95% CI 0·363-0·801) and 0·693 (95% CI 0·482-0·904), respectively, for mild fibrosis; and 0·667 (95% CI 0·363-0·971) and 0·806 (95% CI 0·564-1·000) for at least moderate fibrosis. CONCLUSIONS: This pilot study suggests that ELF may be at least equivalent or possibly superior to PIIINP in the detection of liver fibrosis in patients with psoriasis treated with methotrexate, and supports further investigations into the performance of ELF in this clinical setting.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Fármacos Dermatológicos/efectos adversos , Cirrosis Hepática/inducido químicamente , Metotrexato/efectos adversos , Fragmentos de Péptidos/metabolismo , Procolágeno/metabolismo , Adulto , Anciano , Biomarcadores/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico , Femenino , Humanos , Estilo de Vida , Cirrosis Hepática/diagnóstico , Masculino , Persona de Mediana Edad , Proyectos Piloto , Psoriasis/tratamiento farmacológico , Curva ROC , Estudios Retrospectivos
3.
J Viral Hepat ; 21(6): 430-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24750297

RESUMEN

Assessment of liver fibrosis is important in determining prognosis, disease progression and need for treatment in patients with chronic hepatitis B (CHB). Limitations to the use of liver biopsy in assessing fibrosis are well recognized, and noninvasive tests are being increasingly evaluated including transient elastography (TE) and serum markers such as the Enhanced Liver Fibrosis (ELF) test. We assessed performance of ELF and TE in detecting liver fibrosis with reference to liver histology in a cohort of patients with CHB (n = 182), and compared the performance of these modalities. Median age was 46 and mean AST 70 IU/L. Cirrhosis was reported in 20% of liver biopsies. Both modalities performed well in assessing fibrosis at all stages. Area under receiver operator characteristic (AUROC) curves for detecting METAVIR fibrosis stages F ≥ 1, F ≥ 2, F ≥ 3 and F4 were 0.77, 0.82, 0.80 and 0.83 for ELF and 0.86, 0.86, 0.90 and 0.95 for TE. TE performed significantly better in the assessment of severe fibrosis (AUROC 0.80 for ELF and 0.90 for TE, P < 0.01) and cirrhosis (0.83 for ELF and 0.95 for TE, P < 0.01). This study demonstrates that ELF has good performance in detection of liver fibrosis in patients with CHB, and when compared, TE performs better in detection of severe fibrosis/cirrhosis.


Asunto(s)
Biomarcadores/sangre , Técnicas de Laboratorio Clínico/métodos , Diagnóstico por Imagen de Elasticidad/métodos , Hepatitis B Crónica/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/patología , Adolescente , Adulto , Anciano , Biopsia , Estudios de Cohortes , Femenino , Histocitoquímica , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Sensibilidad y Especificidad , Adulto Joven
4.
J Viral Hepat ; 21 Suppl 1: 60-89, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24713006

RESUMEN

The number of hepatitis C virus (HCV) infections is projected to decline while those with advanced liver disease will increase. A modeling approach was used to forecast two treatment scenarios: (i) the impact of increased treatment efficacy while keeping the number of treated patients constant and (ii) increasing efficacy and treatment rate. This analysis suggests that successful diagnosis and treatment of a small proportion of patients can contribute significantly to the reduction of disease burden in the countries studied. The largest reduction in HCV-related morbidity and mortality occurs when increased treatment is combined with higher efficacy therapies, generally in combination with increased diagnosis. With a treatment rate of approximately 10%, this analysis suggests it is possible to achieve elimination of HCV (defined as a >90% decline in total infections by 2030). However, for most countries presented, this will require a 3-5 fold increase in diagnosis and/or treatment. Thus, building the public health and clinical provider capacity for improved diagnosis and treatment will be critical.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Pruebas Diagnósticas de Rutina/estadística & datos numéricos , Erradicación de la Enfermedad , Quimioterapia Combinada/métodos , Femenino , Salud Global , Hepatitis C Crónica/diagnóstico , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Prevalencia , Adulto Joven
5.
Mucosal Immunol ; 7(1): 89-100, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23715172

RESUMEN

Vaccines that induce T cells, which recognize conserved viral proteins, could confer universal protection against seasonal and pandemic influenza strains. An effective vaccine should generate sufficient mucosal T cells to ensure rapid viral control before clinical disease. However, T cells may also cause lung injury in influenza, so this approach carries inherent risks. Here we describe intranasal immunization of mice with a lentiviral vector expressing influenza nucleoprotein (NP), together with an NFκB activator, which transduces over 75% of alveolar macrophages (AM). This strategy recalls and expands NP-specific CD8+ T cells in the lung and airway of mice that have been immunized subcutaneously, or previously exposed to influenza. Granzyme B-high, lung-resident T-cell populations persist for at least 4 months and can control a lethal influenza challenge without harmful cytokine responses, weight loss, or lung injury. These data demonstrate that AM can be harnessed as effective antigen-presenting cells for influenza vaccination.


Asunto(s)
Memoria Inmunológica , Virus de la Influenza A/inmunología , Macrófagos Alveolares/inmunología , Infecciones por Orthomyxoviridae/inmunología , Mucosa Respiratoria/inmunología , Linfocitos T/inmunología , Traslado Adoptivo , Animales , Linfocitos T CD8-positivos/inmunología , Línea Celular , Reacciones Cruzadas/inmunología , Citocinas/biosíntesis , Epítopos de Linfocito T/inmunología , Femenino , Expresión Génica , Orden Génico , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Humanos , Inmunización , Inmunización Secundaria , Subtipo H1N1 del Virus de la Influenza A/inmunología , Lentivirus/genética , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/patología , Pulmón/virología , Macrófagos Alveolares/metabolismo , Ratones , Infecciones por Orthomyxoviridae/mortalidad , Infecciones por Orthomyxoviridae/terapia , Mucosa Respiratoria/metabolismo , Transducción Genética , Transgenes , Replicación Viral/inmunología
6.
QJM ; 107(1): 17-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24065837

RESUMEN

The availability of the direct-acting antiviral agents (DAAs) boceprevir and telaprevir provides improved treatment outcomes for many patients infected with hepatitis C virus (HCV) genotype 1. However, HCV infection must first be identified before a decision on treatment can be made and currently many patients remain unaware that they have the virus. Given the lack of prompt diagnosis, disease severity should be determined as a baseline reference for treatment, and novel non-invasive techniques for evaluating fibrosis are now available. For patients receiving a DAA regimen, response-guided therapy based on the detection, absence or level of HCV RNA at specified time points is required to achieve an optimal treatment outcome. Knowledge of the test used to measure HCV RNA and its analytical sensitivity, as well as how to interpret the results correctly, are therefore required to administer therapy appropriately. Furthermore, effective treatment management includes appropriate handling of side effects. This increased complexity associated with DAA regimens has resulted in confusion over many aspects of care, including treatment monitoring, viral load result interpretation and the optimal duration of therapy. These issues are discussed here in addition to the benefits of referring patients infected with HCV to a specialist centre.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C/tratamiento farmacológico , Atención a la Salud/organización & administración , Monitoreo de Drogas/métodos , Diagnóstico Precoz , Hepacivirus/aislamiento & purificación , Hepatitis C/diagnóstico , Hepatitis C/virología , Humanos , ARN Viral/sangre , Especialización , Carga Viral
7.
J Viral Hepat ; 16(5): 315-24, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19243499

RESUMEN

Immunomodulators that induce local endogenous interferon-alpha (IFN-alpha) production by plasmacytoid dendritic cells (pDCs) may offer new strategies for the treatment of patients chronically infected with the hepatitis C virus (HCV). However, such an approach may be compromised if reports are true that IFN-alpha production by pDCs from patients with chronic HCV (cHCV) is profoundly impaired. To address the question of pDC dysfunction in cHCV more definitively, in the present study a panel of four prototypic synthetic agonists of toll-like receptor 7 (TLR7) or TLR9 were administered in vitro to pDCs purified from cHCV patients and from normal uninfected donors and their responses compared in terms of not only IFN-alpha production but also the global expression of other cytokines and phenotypic maturation. Plasmacytoid DCs from uninfected donors produced substantial levels of IFN-alpha in response to three of the four agonists and yet only one TLR9 agonist, a class C CpG oligodeoxynucleotide (ODN), induced robust IFN-alpha production by pDCs from cHCV patients. Proinflammatory cytokine production and phenotypic maturation in response to all four agonists was equivalent in infected and uninfected pDCs. These data point to a profound but selective defect in IFN-alpha production by pDCs from cHCV donors. Nonetheless, a class C CpG ODN successfully induced robust IFN-alpha production, suggesting that this class of TLR9 agonist may have utility as a future immunotherapeutic for the treatment of chronic HCV infection.


Asunto(s)
Células Dendríticas/inmunología , Hepatitis C Crónica/inmunología , Factores Inmunológicos/farmacología , Interferón-alfa/biosíntesis , Oligodesoxirribonucleótidos/farmacología , Receptor Toll-Like 9/agonistas , Adulto , Anciano , Células Cultivadas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Receptor Toll-Like 7/agonistas , Adulto Joven
8.
Clin Liver Dis ; 12(4): 883-900, x, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18984472

RESUMEN

Liver fibrosis is a common pathway of injury after chronic insult to the liver. The evolution of liver fibrosis to cirrhosis has many clinical implications, including bleeding, infection, hepatocellular carcinoma, and death. The reference standard for diagnosing liver fibrosis is currently histologic assessment of tissue obtained through liver biopsy. Although this provides valuable information, it has limitations, including its invasiveness, sampling error, observer variability, and the use of categorical scoring systems. This article outlines the various noninvasive markers, including blood tests, imaging, and novel technologies. It examines the principles behind their development, their diagnostic accuracy, and their evolution.


Asunto(s)
Diagnóstico por Imagen/métodos , Cirrosis Hepática/sangre , Cirrosis Hepática/diagnóstico , Biomarcadores/sangre , Enfermedad Crónica , Humanos , Hígado/diagnóstico por imagen , Hígado/metabolismo , Cirrosis Hepática/diagnóstico por imagen , Pruebas de Función Hepática/métodos , Pruebas de Función Hepática/tendencias , Sensibilidad y Especificidad , Ultrasonografía
9.
QJM ; 101(8): 631-41, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18522976

RESUMEN

BACKGROUND: New techniques for diagnosing hereditary haemochromatosis (HHC) have become available alongside traditional tests such as liver biopsy and serum iron studies. AIM: To evaluate DNA tests in people suspected of having haemochromatosis at clinical presentation compared to liver biopsy, and in family members of those diagnosed with haemochromatosis compared to phenotypic iron studies in UK. METHODS: Decision analytic models were constructed to compare the costs and consequences of the diagnostic strategies for a hypothetical cohort of people with suspected haemochromatosis. For each strategy, the number of cases of haemochromatosis identified and treated and the resources used were estimated. RESULTS: For diagnostic strategies in people suspected clinically of having haemochromatosis, the DNA strategy is cost saving compared to liver biopsy (cost saved per case detected, 123 pounds) and continues to be so across all ranges of parameters. For family testing, the DNA strategy is cost saving for the offspring of the proband but not for siblings. If the DNA test cost were to reduce by 40% to 60 pounds or, if in the phenotypic model, those with initially normal iron indices were retested twice instead of once, the DNA strategy would be the cheaper one. CONCLUSION: Diagnostic strategies involving DNA testing are likely to be cost saving in clinical cases with iron overload and in the offspring of index cases. This study supports the UK guideline recommendations for the use of DNA testing in UK.


Asunto(s)
ADN/análisis , Técnicas de Apoyo para la Decisión , Hemocromatosis/diagnóstico , Sobrecarga de Hierro/diagnóstico , Hierro/sangre , Biopsia/economía , Biopsia/métodos , Análisis Costo-Beneficio , Árboles de Decisión , Femenino , Marcadores Genéticos/genética , Pruebas Genéticas , Hemocromatosis/genética , Humanos , Sobrecarga de Hierro/genética , Hígado/patología , Masculino , Fenotipo , Sensibilidad y Especificidad , Oligoelementos , Reino Unido
10.
Clin Exp Immunol ; 152(2): 265-73, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18341617

RESUMEN

We have described previously an immunostimulant derived from Onchocerca volvulus, the helminth parasite that causes onchocerciasis. Recombinant O. volvulus activation-associated secreted protein-1 (rOv-ASP-1) was a potent adjuvant for antibody and cellular responses to protein, polypeptide and small peptide antigens. Our aims were to determine whether rOv-ASP-1 is immunostimulatory for human peripheral blood mononuclear cells (PBMC) and, if so, whether it could augment cellular responses against human pathogen antigens in vitro. Cytokines from rOv-ASP-1-stimulated human PBMC were measured by a fluorescence activated cell sorter-based multiplex assay. Recall responses of normal healthy donor (NHD) and chronic hepatitis C virus (c-HCV)-infected patient PBMC to tetanus toxoid (TT) or HCV core (HCVco) antigen, respectively, were measured by interferon-gamma enzyme-linked immunospot assays. Interferon-gamma was the predominant cytokine induced by rOv-ASP-1. 77.3% of NHD anti-TT and 88.9% of c-HCV anti-HCVco responses were enhanced by rOv-ASP-1. The immunostimulant effect was dependent upon contact between CD56+ and CD56- fractions of PBMC. We have described a helminth-derived protein that can act as an immunostimulant for human recall responses in vitro to TT and, perhaps more importantly, HCV antigens in patients with chronic HCV infection. Our longer-term goal would be to boost anti-viral responses in chronic infections such as HCV.


Asunto(s)
Antígenos Helmínticos/inmunología , Antígenos Virales/inmunología , Proteínas del Helminto/inmunología , Hepacivirus/inmunología , Subgrupos Linfocitarios/inmunología , Toxoide Tetánico/inmunología , Adyuvantes Inmunológicos , Adulto , Anciano , Antígeno CD56/análisis , Comunicación Celular/inmunología , Células Cultivadas , Citocinas/biosíntesis , Femenino , Hepatitis C Crónica/inmunología , Humanos , Memoria Inmunológica , Mediadores de Inflamación/metabolismo , Interferón gamma/biosíntesis , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/inmunología
11.
Clin Exp Immunol ; 148(3): 494-500, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17362265

RESUMEN

Monocyte-derived dendritic cells (MoDCs) are a promising cellular adjuvant for effector immune responses against tumours and chronic viral infections, including hepatitis C virus (HCV). If autologous DC therapeutic approaches are to be applied in persistent HCV infections in patients, it is important to have an unambiguous understanding of the functional status of the cell type used, namely MoDCs from patients with chronic hepatitis C (CHC) infection. Because of conflicting published reports of either impaired or normal MoDC function in CHC infection, we re-examined the ability of MoDCs from CHC and normal healthy donors (NHD) to mature to an inflammatory stimulus [tumour necrosis factor (TNF)-alpha] and their subsequent functional capabilities. Expression of maturation-associated phenotypic markers [human leucocyte antigen (HLA)-DR, CD83, CD86, CD40], allostimulatory capacity in mixed lymphocyte reactions (MLRs) and CD40-ligand-induced cytokine and chemokine generation were compared in CHC- versus NHD-MoDCs. TNF-alpha-stimulated CHC-MoDCs up-regulated phenotypic markers, but to significantly lower levels than NHD-MoDCs. At physiological ratios of DCs to T cells, CHC-MoDCs were less allostimulatory than NHD-MoDCs, but not when DC numbers were substantially increased. CHC- and NHD-MoDCs generated equivalent amounts of cytokines [TNF-alpha, interleukin (IL)-1beta, IL-6, IL-12p70, IL-15, IL-10] and chemokines [interferon-inducible protein (IP)-10, macrophage inflammatory protein (MIP)-1alpha, regulated upon activation, normal T expressed and secreted (RANTES)] after CD40 ligation. Because the functional defect was not apparent at high MoDC : T cell ratios, autologous MoDC therapy with sufficiently high numbers of DCs could, in theory, overcome any impairment of MoDC function in CHC.


Asunto(s)
Células Dendríticas/inmunología , Hepatitis C Crónica/inmunología , Monocitos/inmunología , Adulto , Anciano , Diferenciación Celular/inmunología , Células Cultivadas , Quimiocinas/biosíntesis , Citocinas/biosíntesis , Femenino , Citometría de Flujo/métodos , Humanos , Inmunocompetencia , Prueba de Cultivo Mixto de Linfocitos , Masculino , Persona de Mediana Edad , Factor de Necrosis Tumoral alfa/inmunología
12.
Gut ; 55(11): 1650-60, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17047111

RESUMEN

The diagnosis of fibrosis within liver disease is important for prognosis, stratification for treatment, and monitoring of treatment efficacy. The rising incidence and prevalence of non-alcoholic fatty liver disease (NAFLD) has driven the search for accurate non-invasive tools of liver fibrosis within this condition. With the aid of a systematic review, we explore how the field has evolved from the discovery of simple blood parameters to panel markers of liver fibrosis. We will discuss the biological plausibility, limitations, potential uses, and emerging diagnostic techniques of non-invasive markers in this rapidly expanding field.


Asunto(s)
Hígado Graso/complicaciones , Cirrosis Hepática/etiología , Biomarcadores/sangre , Hígado Graso/diagnóstico , Humanos , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/patología , Índice de Severidad de la Enfermedad
14.
Gut ; 52(10): 1500-4, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12970145

RESUMEN

BACKGROUND: Hepatitis C virus (HCV) infection is a major public health problem recognised by the UK National Strategy that proposes that a care pathway for assessment, diagnosis, and treatment be established in all prisons, integrated within managed clinical networks. A prison sentence provides the opportunity to focus on traditionally hard to reach patients. AIMS: To evaluate the prevalence of HCV infection in a UK prison cluster and to assess the effectiveness of a prison outreach service for hepatitis C. SUBJECTS: Male prisoners. METHODS: A nurse specialist led clinic within a cluster of adult prisons was established, offering health education on hepatitis C, advice on harm minimisation, and HCV testing. Infected prisoners were offered access to a care pathway leading to treatment. Outcome measures were uptake of the service, and diagnosis and treatment of hepatitis C. RESULTS: A total of 8.5% of 1618 prisoners accepted testing: 30% had active infection with HCV. Most were ineligible for treatment due to psychiatric illness or did not receive treatment for logistic reasons. Injecting drug use was the major risk factor in all cases. Only 7% of HCV polymerase chain amplification positive inmates received treatment in prison. CONCLUSION: There is a large pool of HCV infected prisoners at risk of complications, constituting a source of infection during their sentence and after discharge. A prison outreach clinic and care pathway was perceived as effective in delivering health education, reducing the burden on prison and hospital services. It provided an opportunity for intervention but had a limited effect in eradicating HCV in prisoners and it remains unclear how this might be achieved.


Asunto(s)
Política de Salud , Hepatitis C/diagnóstico , Hepatitis C/prevención & control , Servicio Ambulatorio en Hospital/organización & administración , Prisioneros , Prisiones/organización & administración , Adulto , Relaciones Comunidad-Institución , Inglaterra , Humanos , Masculino , Enfermeras Clínicas , Educación del Paciente como Asunto , Prevalencia , Factores de Riesgo , Abuso de Sustancias por Vía Intravenosa
16.
J Viral Hepat ; 9(1): 18-28, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11851899

RESUMEN

CD8+ T lymphocyte responses are important in the clearance of viral infections. In chronic infections they may contribute to pathogenesis. To investigate the role of CD8+ T lymphocyte responses in viral clearance and chronic hepatitis C we have compared hepatitis C virus (HCV) specific cytotoxicity and interferon-gamma (IFN-gamma) production in patients with resolved-acute, and chronic HCV infection. CD8+ T cell responses to a panel of 13 HCV T cell peptide epitopes were studied using Elispot assays of IFN-gamma production and chromium release cytotoxicity assays. Responses of seven patients with resolved acute HCV infection were compared with those of 14 chronically infected patients. HCV-specific cytotoxicity differentiated the two populations of patients. The majority (71%) of patients with resolved acute infection tested positive to 42% of relevant peptides compared with the minority (28%) of patients with chronic hepatitis C (P=0.03) who responded to only 8% of relevant peptides (P=0.0009). In contrast, HCV-specific IFN-gamma production was detected in 86% of patients with either resolved or chronic infection in response to 42% and 35%, respectively, of relevant peptides tested (not significant). In patients with chronic infection the magnitude of the HCV-specific IFN-gamma production was inversely correlated to viral load (R2=0.52; P=0.042). Failure to clear HCV infection may be attributable to the presence of noncytolytic IFN-gamma producing CD8+ T lymphocytes in chronically infected patients. However these CD8+ T cells may play a beneficial role in contributing to the control of viral load in chronic hepatitis C.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Hepatitis C Crónica/inmunología , Hepatitis C/inmunología , Enfermedad Aguda , Adulto , Anciano , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/virología , Línea Celular Transformada , Células Cultivadas , Citotoxicidad Inmunológica , Epítopos de Linfocito T/inmunología , Femenino , Hepatitis C/sangre , Hepatitis C Crónica/sangre , Humanos , Inmunofenotipificación , Interferón gamma/biosíntesis , Masculino , Persona de Mediana Edad
17.
Hepatology ; 30(4): 1037-44, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10498657

RESUMEN

How Hepatitis C Virus (HCV) causes persistent infection is unknown. One hypothesis is that HCV evades the host immune response through mutation in immune epitopes. We have investigated mutations in the HCV genome to see if they cluster within immune epitopes; and we have studied the effect of antibody deficiency on mutation rates. We studied patients with chronic hepatitis C, 3 with antibody deficiency and 3 with normal immunity. Regions of the core and envelope genes of HCV, encoding cytotoxic (CTL), and B cell epitopes were sequenced at 2 time points, 2 years apart. The diversity of quasispecies increased with time. The HCV genetic mutation rate was higher than previously predicted. The cryptic nucleotide mutation rate in core was similar to that observed in envelope, suggesting that the error rate of the HCV RNA polymerase is similar in both regions. In contrast, the coding mutation rate was decreased in core and increased in envelope. No genetic mutation was seen in any of the core CTL epitopes despite detectable cellular responses. All patients had mutations within a previously described envelope CTL epitope but did not exhibit immune responses to either index or mutated peptides. There was no difference in mutation rates in any cellular or humoral epitopes between patients with antibody deficiency and normal immunity. Thus we have found no evidence that mutations were selected by T-lymphocytes or antibodies. These findings implicate alternative virus-host interactions in the selection of HCV mutations.


Asunto(s)
Variación Genética , Hepacivirus/genética , Hepacivirus/inmunología , Proteínas del Núcleo Viral/genética , Proteínas del Envoltorio Viral/genética , Adulto , Agammaglobulinemia/inmunología , Anciano , Secuencia de Aminoácidos/genética , Anticuerpos/análisis , Linfocitos B/inmunología , Secuencia de Bases/genética , Epítopos/genética , Femenino , Humanos , Región Variable de Inmunoglobulina/genética , Masculino , Datos de Secuencia Molecular , Mutación , Valores de Referencia , Linfocitos T Citotóxicos/inmunología
19.
Mamm Genome ; 9(3): 220-5, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9501306

RESUMEN

We have generated a detailed physical map of the 6p21.3/p22.1 boundary, using a combination of yeast artificial chromosome (YAC) fragmentation and high-resolution sequence tagged site (STS) content mapping. YACs from the CEPH, St. Louis, and ICRF libraries have been used to construct a 4.5-Mb contig spanning the markers D6S306 to D6S1571. YAC insert sizes were determined by pulsed field gel electrophoresis (PFGE). Chimerism of YACs was determined by fluorescent in situ hybridization (FISH), and their integrity was determined by fingerprinting with Alu-PCR. We have identified 10 new CA repeat loci in this region as well as over 50 novel STSs, several tRNA genes, a new histone H2B gene and the phospholipase D gene. Using these new markers, we have rapidly generated a bacterial clone contig of over 250 kb, spanning the markers D6S1260 to D6S1918 (WI-3111) with STSs spaced on average every 6 kb.


Asunto(s)
Mapeo Cromosómico , Cromosomas Artificiales de Levadura , Hibridación Fluorescente in Situ/métodos , Lugares Marcados de Secuencia , Animales , Secuencia de Bases , Cromosomas Bacterianos , Marcadores Genéticos , Histonas/genética , Humanos , Ratones , Datos de Secuencia Molecular , ARN de Transferencia de Serina , ARN de Transferencia de Valina
20.
J R Coll Physicians Lond ; 32(6): 557-63, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9881313

RESUMEN

OBJECTIVE: To evaluate the effect of a three-hour training session in formulating questions and searching databases. DESIGN: A randomised controlled trial and before and after study, with blinded outcome assessment. SETTING: Oxford University Medical School, first clinical year. SUBJECTS: Altogether 108 medical students were randomly assigned to an experimental group (54) or a control group (54), and all were given the task of searching for evidence around an ulcer related problem or a cardiac problem. Students in the experimental group were randomly allocated to research one of the two problems before training and the remaining problem afterwards. Control students received no training and were randomly allocated to search for evidence around either of these problems. MAIN OUTCOME MEASURES: Searching performance; the quality of evidence retrieved; student satisfaction. RESULTS: Training improved the students' search performance and the quality of evidence retrieved. Students' satisfaction with the training was high. CONCLUSIONS: A three-hour interactive training session improved the students' ability to search databases and retrieve evidence and was well received by the students.


Asunto(s)
Educación de Pregrado en Medicina , Medicina Basada en la Evidencia/educación , Almacenamiento y Recuperación de la Información , MEDLINE , Informática Médica/educación , Investigación/educación , Adulto , Anciano , Enfermedades Cardiovasculares/terapia , Ensayos Clínicos como Asunto , Intervalos de Confianza , Método Doble Ciego , Evaluación Educacional , Femenino , Humanos , Masculino , Estadísticas no Paramétricas , Úlcera/terapia , Reino Unido
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