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1.
J Hepatol ; 74(5): 1064-1074, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33278456

RESUMEN

BACKGROUND & AIMS: Factors associated with a successful outcome upon nucleos(t)ide analogue (NA) treatment withdrawal in HBeAg-negative chronic hepatitis B (CHB) patients have yet to be clarified. The objective of this study was to analyse the HBV-specific T cell response, in parallel with peripheral and intrahepatic viral parameters, in patients undergoing NA discontinuation. METHODS: Twenty-seven patients without cirrhosis with HBeAg-negative CHB with complete viral suppression (>3 years) were studied prospectively. Intrahepatic HBV-DNA (iHBV-DNA), intrahepatic HBV-RNA (iHBV-RNA), and covalently closed circular DNA (cccDNA) were quantified at baseline. Additionally, serum markers (HBV-DNA, HBsAg, HBV core-related antigen [HBcrAg] and HBV-RNA) and HBV-specific T cell responses were analysed at baseline and longitudinally throughout follow-up. RESULTS: After a median follow-up of 34 months, 22/27 patients (82%) remained off-therapy, of whom 8 patients (30% of the total cohort) lost HBsAg. Baseline HBsAg significantly correlated with iHBV-DNA and iHBV-RNA, and these parameters were lower in patients who lost HBsAg. All patients had similar levels of detectable cccDNA regardless of their clinical outcome. Patients achieving functional cure had baseline HBsAg levels ≤1,000 IU/ml. Similarly, an increased frequency of functional HBV-specific CD8+ T cells at baseline was associated with sustained viral control off treatment. These HBV-specific T cell responses persisted, but did not increase, after treatment withdrawal. A similar, but not statistically significant trend, was observed for HBV-specific CD4+ T cell responses. CONCLUSIONS: Decreased cccDNA transcription and low HBsAg levels are associated with HBsAg loss upon NA discontinuation in patients with HBeAg-negative CHB. The presence of functional HBV-specific T cells at baseline are associated with a successful outcome after treatment withdrawal. LAY SUMMARY: Nucleos(t)ide analogue therapy can be discontinued in a high proportion of chronic hepatitis B patients without cirrhosis. The strength of HBV-specific immune T cell responses may contribute to successful viral control after antiviral treatment interruption. Our comprehensive study provides in-depth data on virological and immunological factors than can help guide individualised therapy in patients with chronic hepatitis B.


Asunto(s)
ADN Viral/aislamiento & purificación , Antígenos de la Hepatitis B , Virus de la Hepatitis B , Hepatitis B Crónica , Inmunidad Celular , Hígado , Nucleósidos/uso terapéutico , Privación de Tratamiento/estadística & datos numéricos , Antivirales/uso terapéutico , Biomarcadores/sangre , ADN Circular/aislamiento & purificación , Femenino , Antígenos de la Hepatitis B/análisis , Antígenos de la Hepatitis B/aislamiento & purificación , Antígenos de Superficie de la Hepatitis B/análisis , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/sangre , Hepatitis B Crónica/diagnóstico , Humanos , Inmunidad Celular/efectos de los fármacos , Inmunidad Celular/inmunología , Hígado/patología , Hígado/virología , Masculino , Persona de Mediana Edad , Planificación de Atención al Paciente
2.
World J Gastroenterol ; 24(6): 752-762, 2018 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-29456414

RESUMEN

AIM: To assess the seroprevalence of hepatitis B virus (HBV) immunity among previously vaccinated pediatric liver transplant recipients and present a case report of de novo hepatitis B infection after liver transplantation. METHODS: This study focused on children with chronic liver diseases who received primary hepatitis B immunization and had a complete dataset of anti-HBs before and after liver transplantation between May 2001 and June 2017. Medical records were retrospectively reviewed for potential factors relating to HBV immunity loss. RESULTS: In total, 50 children were recruited. The mean time from liver transplantation to anti-HBs testing was 2.53 ± 2.11 years. The mean anti-HBs levels before and after liver transplantation were 584.41 ± 415.45 and 58.56 ± 6.40 IU/L, respectively. The rate of non-immunity (anti-HBs < 10 IU/L) in the participants was 46% (n = 26) at one year, 57% (n = 7) at two years and 82% (n = 17) at > three years following liver transplantation. The potential factors relating to HBV immunity loss after liver transplantation were identified as anti-HBs (P = 0.002), serum albumin (P = 0.04), total bilirubin (P = 0.001) and direct bilirubin (P = 0.003) before liver transplantation. A five-year-old boy with biliary cirrhosis received 4 doses of HBV vaccine with an anti-HBs titer of > 1000 IU/L and underwent liver transplantation; his anti-HBc-negative father was the donor. After liver transplantation, the boy had stenosis of the hepatic artery up to the inferior vena cava anastomosis and underwent venoplasty three times. He also received subcutaneous injections of enoxaparin for 5 mo and 20 transfusions of blood components. Three years and ten months after the liver transplantation, transaminitis was detected with positive tests for HBsAg, HBeAg, and anti-HBc (2169.61, 1706 and 8.45, respectively; cutoff value: < 1.00) and an HBV viral load of 33212320 IU/mL. CONCLUSION: The present study showed that loss of hepatitis B immunity after liver transplantation is unexpectedly common. In our case report, despite high levels of anti-HBs prior to transplantation, infection occurred at a time when, unfortunately, the child had lost immunity to hepatitis B after liver transplantation.


Asunto(s)
Enfermedad Hepática en Estado Terminal/cirugía , Anticuerpos contra la Hepatitis B/sangre , Vacunas contra Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Hepatitis B/inmunología , Trasplante de Hígado/efectos adversos , Niño , Preescolar , Enfermedad Hepática en Estado Terminal/inmunología , Femenino , Hepatitis B/sangre , Hepatitis B/diagnóstico , Hepatitis B/virología , Anticuerpos contra la Hepatitis B/inmunología , Antígenos de la Hepatitis B/inmunología , Antígenos de la Hepatitis B/aislamiento & purificación , Vacunas contra Hepatitis B/administración & dosificación , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Donadores Vivos , Masculino , Vacunación Masiva , Estudios Retrospectivos , Estudios Seroepidemiológicos , Pruebas Serológicas
3.
Occup Environ Med ; 73(12): 857-863, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27484956

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) transmission is known to occur through direct contact with infected blood. There has been some suspicion that the virus can also be detected in aerosol form. However, this has never been directly shown. The purpose of this study was to sample and analyse surgical smoke from laparoscopic surgeries on patients with hepatitis B to determine whether HBV is present. METHODS: A total of 11 patients who underwent laparoscopic or robotic abdominal surgeries between October 2014 and February 2015 at Korea University Anam Hospital were included in this study. A high efficiency collector was used to obtain surgical smoke in the form of hydrosol. The smoke was analysed by using nested PCR. RESULTS: Robotic or laparoscopic colorectal resections were performed in 5 cases, laparoscopic gastrectomies in 3 cases and laparoscopic hepatic wedge resections in another 3 cases. Preoperatively, all of the patients had positive hepatitis B surface antigen (HBsAg). 2 patients had detectable HBsAb, and 2 were positive for hepatitis B e antigen. 3 patients were taking antihepatitis B viral medications at the time of the study. The viral load measured in the patients' blood was undetectable to 1.7×108 IU/mL. HBV was detected in surgical smoke in 10 of the 11 cases. CONCLUSIONS: HBV is detectable in surgical smoke. This study provides preliminary data in the investigation of airborne HBV infection.


Asunto(s)
Antígenos de la Hepatitis B/aislamiento & purificación , Virus de la Hepatitis B/aislamiento & purificación , Laparoscopía , Exposición Profesional/análisis , Humo/análisis , Adulto , Anciano , Monitoreo del Ambiente , Femenino , Hospitales Universitarios , Humanos , Laparoscopía/efectos adversos , Masculino , Persona de Mediana Edad , Exposición Profesional/efectos adversos , Reacción en Cadena de la Polimerasa , República de Corea , Humo/efectos adversos
4.
World J Gastroenterol ; 20(35): 12485-92, 2014 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-25253948

RESUMEN

A biosensor is an analytical device used for the detection of analytes, which combines a biological component with a physicochemical detector. Recently, an increasing number of biosensors have been used in clinical research, for example, the blood glucose biosensor. This review focuses on the current state of biosensor research with respect to efficient, specific and rapid detection of hepatitis B virus (HBV). The biosensors developed based on different techniques, including optical methods (e.g., surface plasmon resonance), acoustic wave technologies (e.g., quartz crystal microbalance), electrochemistry (amperometry, voltammetry and impedance) and novel nanotechnology, are also discussed.


Asunto(s)
Técnicas Biosensibles , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/diagnóstico , Acústica , Animales , Técnicas Biosensibles/instrumentación , ADN Viral/aislamiento & purificación , Técnicas Electroquímicas , Diseño de Equipo , Hepatitis B/virología , Anticuerpos contra la Hepatitis B/aislamiento & purificación , Antígenos de la Hepatitis B/aislamiento & purificación , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Humanos , Nanomedicina , Valor Predictivo de las Pruebas , Resonancia por Plasmón de Superficie , Transductores , Carga Viral
6.
Cent Eur J Public Health ; 21(1): 22-5, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23741894

RESUMEN

OBJECTIVES: The aim of this study was to determine the prevalence of HBV infection among pregnant women in districts of Eastern Slovakia with a diverse prevalence of Roma population. METHODS: Overall 59,279 serum samples from 9 regional departments of clinical microbiology from Eastern Slovakia were collected in the period from January 2008 till December 2009 and analysed. RESULTS: The number of HBsAg positive samples overall and during pregnancy was 1.74% and 2.12%, respectively. Comparing districts with higher (> 5%) and lower (< 5%) Roma population, there was no significant difference in the prevalence of HBsAg positive samples overall (1.95% vs.1.62%). However, in the subgroup of pregnant women the prevalence of HBsAg positive samples (2.72% vs. 0.95%) differs significantly (p < 0.01). CONCLUSIONS: The prevalence of HBV infection among pregnant women in Eastern Slovakia did not rapidly exceed the estimated nationwide prevalence. However, in districts with higher Roma population the expected higher prevalence of HBV infection was confirmed. This indicates the need to pay special attention to the prevention of hepatitis B in these districts.


Asunto(s)
Hepatitis B/etnología , Hepatitis B/epidemiología , Complicaciones Infecciosas del Embarazo/etnología , Complicaciones Infecciosas del Embarazo/virología , Femenino , Hepatitis B/virología , Antígenos de la Hepatitis B/aislamiento & purificación , Humanos , Vigilancia de la Población , Embarazo , Eslovaquia/epidemiología
7.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 30(6): 312-314, jun. -jul. 2012.
Artículo en Inglés | IBECS | ID: ibc-104116

RESUMEN

Introduction: The aim of this study was to assess the prevalence of occult HBV infection in HIV-positive patients in a centre in Southern Spain. Methods: The HBV serological markers were investigated in all the patients and the presence of HBV-DNA was tested by PCR in patients with isolated anti-HBc. Results: An isolated anti-HBc pattern was detected in 144/520 (27.7%) patients. HBV-DNA was detected in one of these patients (0.7%).Conclusions: In Southern Spain, there is a low prevalence of occult HBV infection among HIV-infected patients, despite increasing immigration from endemic countries (AU)


Introducción: El objetivo de este estudio fue evaluar la prevalencia de infección oculta por VHB en pacientes infectados por VIH del sur de España. Métodos: Se investigaron los marcadores serológicos para VHB y se analizó la presencia de ADN-VHB en los anti-HBc "solo". Resultados: El patrón anti-HBc "solo" fue detectado en 144/520 (27,7%) pacientes. El ADN-VHB fue detectado en un paciente (0,7%).Conclusiones: La prevalencia de infección oculta por VHB es baja entre los pacientes infectados por VIH a pesar del aumento en la inmigración desde países endémicos (AU)


Asunto(s)
Humanos , Infecciones por VIH/epidemiología , Hepatitis B Crónica/epidemiología , Comorbilidad , Anticuerpos contra la Hepatitis B/aislamiento & purificación , Antígenos de la Hepatitis B/aislamiento & purificación , Virus de la Hepatitis B/genética , Biomarcadores/análisis
8.
Pediatr. catalan ; 71(1): 7-12, ene.-mar. 2011. tab, ilus
Artículo en Español | IBECS | ID: ibc-131384

RESUMEN

Fundamento. La inmigración es importante en nuestro medio. Algunos protocolos de atención al niño inmigrante incluyen la determinación del estado serológico respecto al virus de la hepatitis B (VHB). Objetivo. Valorar la conveniencia de la determinación sistemática del antígeno de superficie (HBsAg), anticuerpo contra el core (HBSerologia del virus de l’hepatitis B en infants recentment immigrats Ana Estabanell 1, Rosa M. Masvidal 2, Elisa de Frutos 2, Dolors Riera 3, Cecilia Cruz 1, Beatriz Miguel 2 1 CAP Gòtic (annex Rull). ABS Gòtic. Institut Català de la Salut. Barcelona. 2 CAP Dr. Lluís Sayé. ABS Raval Nord. Institut Català de la Salut. Barcelona. 3 CAP Drassanes. ABS Raval Sud. Institut Municipal d’Assistència Sanitària de Barcelona. cAc), anticuerpo contra el Ag de superficie (HBsAc), en niños inmigrantes. Determinar la prevalencia del HBsAc positivo en los vacunados contra el VHB. Método. Se determinaron HbsAg, HBsAc, HBcAc en niños de 6 meses a 15 años procedentes de países de baja renta que habían llegado hacía menos de 12 meses. Se registró su estado vacunal. Se estimó la prevalencia y el intervalo de confianza del resultado. Resultados. De los 1.226 niños/as, se determinó el HbsAg en 1.098 (89,5%), siendo 8 positivos: 0,79% (intervalo de confianza (IC) 95%: 0,37-1,43), dos de éstos constaban como vacunados para el VHB. En 1.024 se determinó el HBcAc, siendo el único marcador positivo en 7 casos: 0,98% (IC 0,47-1,80); el HBsAc se determinó en 987 y fue positivo en el 33,23%. De los 333 niños vacunados con tres dosis, en 267 se determinó el HBsAc, siendo positivo en el 59,9% (IC 95%: 55,15-64,45). Conclusiones. Consideramos indicada la determinación del HbsAg a los niños inmigrantes, incluyendo los que aportan datos de vacunación del VHB completa. No creemos justificado solicitar el HBcAc de manera sistemática. En niños inmigrantes vacunados puede estar indicado determinar los HBsAc(AU)


Background. Immigration is an important phenomenon in our environment. Some guidelines for the care of the immigrant child include the evaluation of hepatitis B virus (HBV) serology. Objective. To evaluate the need for the systematic measurement of surface antigen (HBsAg), core antigen antibody (HBcAb), and surface antigen antibody (HBsAb) in young immigrants, and to determine the prevalence of HBsAb in those who receive HBV vaccination. Method. HBsAg, HBsAb, and HBcAb values were determined in children from 6 months to 15 years of age who emigrated from low-income countries within the prior 12 months. The prevalence and confidence intervals were calculated. Results. Of the 1,226 children evaluated, HBsAg was measured in 1,098 (89.5%) and was positive in 8 (0.79%, CI 0.37-1.43), including two cases in whom vaccination had been documented; HBcAb was measured in 1,024 and was the only positive HBV marker in 7 cases (0.98%, CI 0.47-1.80); and HBsAb was measured in 987 and was positive in 33.26%. In 30.8% of the children, the only positive marker was HBsAb. Of the 333 children Background. Immigration is an important phenomenon in our environment. Some guidelines for the care of the immigrant child include the evaluation of hepatitis B virus (HBV) serology. Objective. To evaluate the need for the systematic measurement of surface antigen (HBsAg), core antigen antibody (HBcAb), and surface antigen antibody (HBsAb) in young immigrants, and to determine the prevalence of HBsAb in those who receive HBV vaccination. Method. HBsAg, HBsAb, and HBcAb values were determined in children from 6 months to 15 years of age who emigrated from low-income countries within the prior 12 months. The prevalence and confidence intervals were calculated. Results. Of the 1,226 children evaluated, HBsAg was measured in 1,098 (89.5%) and was positive in 8 (0.79%, CI 0.37-1.43), including two cases in whom vaccination had been documented; HBcAb was measured in 1,024 and was the only positive HBV marker in 7 cases (0.98%, CI 0.47-1.80); and HBsAb was measured in 987 and was positive in 33.26%. In 30.8% of the children, the only positive marker was HBsAb. Of the 333 children(AU)


Asunto(s)
Humanos , Masculino , Femenino , Niño , Hepatitis B/sangre , Serología/métodos , Serología/normas , Emigrantes e Inmigrantes/clasificación , Hepatitis , Hepatitis B/prevención & control , Anticuerpos contra la Hepatitis B/uso terapéutico , Antígenos de la Hepatitis B/inmunología , Antígenos de la Hepatitis B/aislamiento & purificación , Antígenos e de la Hepatitis B , Emigración e Inmigración/tendencias , Migrantes/clasificación , Hepatitis B/inmunología , Vacunación Masiva/métodos , Vacunación/métodos , Vacunación/tendencias
9.
J Am Coll Health ; 59(1): 37-41, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20670927

RESUMEN

UNLABELLED: The prevalence of chronic hepatitis B (HBV) among college-age US-born Asian and Pacific Islanders (A/PI) is not well known. OBJECTIVES: To compare the prevalence of hepatitis B surface antigen (HBsAg) seropositivity in US-born to A/PI-born students at a public university. PARTICIPANTS: Undergraduate who self-identified themselves as A/PI. RESULTS: Of 145 US-born A/PI, 1.4% (confidence interval [CI] = 0.0%, 3.3%) tested positive for HBsAg compared to 3.3% (CI = 0.5%, 6.1%) of the 152 A/PI-born students. Approximately 1/3 of all students were unaware of their HBV vaccination status. CONCLUSIONS: HBsAg prevalence among A/PI undergraduates, including US-born, is considerably higher (3 to 11 times) than the mainstream US population (0.3% to 0.5%) and supports the Centers for Disease Control and Prevention (CDC) recommendations for testing all persons of A/PI ancestry, including US-born persons whose parents were born in regions with HBsAg prevalence of >or=8%. Awareness of HBV vaccination status was relatively low and vaccination did not assure that individuals were HBsAg negative.


Asunto(s)
Asiático , Antígenos de la Hepatitis B/aislamiento & purificación , Hepatitis B/epidemiología , Nativos de Hawái y Otras Islas del Pacífico , Estudiantes , Adulto , Femenino , Humanos , Masculino , Estados Unidos/epidemiología , Universidades , Adulto Joven
10.
Med. clín (Ed. impr.) ; 132(17): 649-653, mayo 2009. tab
Artículo en Español | IBECS | ID: ibc-60636

RESUMEN

Fundamento y objetivo: Detectar casos asintomáticos relacionados con un brote, valorar la seroprevalencia de hepatitis B (HB) en deportistas de orientación y establecer recomendaciones. Pacientes y método: Se realizó un estudio transversal de seroprevalencia entre 116 deportistas de orientación que habían competido en las categorías implicadas en un brote previo y una muestra estratificada de 166 corredores del resto de otras categorías de competición. Se analizaron marcadores de HB: antígeno de superficie del virus de la HB (VHB) (HBsAg), anticuerpo contra el antígeno core del VHB (anti-HBc), anticuerpos contra el HBsAg, anti-HBc tipo inmunoglobina M y antecedentes de vacunación. Los resultados se expresan utilizando pesos ponderados. Resultados: La seroprevalencia de HB (anti-HBc positivos) fue del 6,7% (n=12; intervalo de confianza [IC] del 95%: 0,6 a 12,9). No se observó ningún caso de HB aguda o crónica. Todos los marcadores fueron negativos para el 61,1% (n=64; IC del 95%: 46,3 a 75,6), y el 32,3% (n=29; IC del 95%: 18,2 a 46,4) tenía marcadores de inmunidad por vacunación. Entre los sujetos menores de 25 años, el 28,4% estaba sin vacunar a pesar de que entraban en el calendario vacunal. Conclusiones: Los resultados muestran que la seroprevalencia de HB entre deportistas de orientación no difiere de la población general. Sin embargo, es necesario reforzar la vacunación entre adolescentes y adultos jóvenes. Se dan recomendaciones generales para la prevención de HB a las federaciones de orientación (AU)


Background and objective: Our objectives were to detect asymptomatic cases involved in an outbreak of hepatitis B, to assess the seroprevalence of hepatitis B (HB) in orienteers and to establish recommendations. Patients and method: One hundred sixteen orienteers who had competed in the categories involved in the previous outbreak as well as a stratified random sample of 166 of the remaining orienteers in other competition categories were included in a cross-sectional serological prevalence study. HB surface antigen (anti-HBs); total antibody to HB core antigen (total anti-HBc); HB surface antigen (Ag HBs); and antibody IgM to HB core antigen (anti-HBcIgM) along with the history of vaccination for hepatitis B were analyzed. The results were weighted. Results: The seroprevalence of HB (total anti-HBc positive) was 6.7% (n=12, 95%CI 0.6-12.9). No case of acute HB or chronic infection was observed. All the serological markers were negative for 61.1% (n=64, 95%CI 46.3-75.6), and 31.5% (n=29, 95%CI 18.2-46.4) had markers of immunity due to vaccination. Among individuals under 25 years of age, 28.4% were unvaccinated, although they were covered by vaccination programs. Conclusion: Our results suggest that the seroprevalence of HB among orienteers is not different from the general population in Spain. However, it is necessary to reinforce the vaccination among adolescents and young adults. General recommendations for the prevention of HB were made to orienteering federations (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Hepatitis B Crónica/epidemiología , Antígenos de la Hepatitis B/aislamiento & purificación , Vacunas contra Hepatitis B/administración & dosificación , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/transmisión , Anticuerpos contra la Hepatitis B/aislamiento & purificación , Distribución por Edad , Deportes
11.
Int J Infect Dis ; 13(3): 394-8, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19036623

RESUMEN

OBJECTIVE: To examine the presence of hepatitis B surface antigen (HBsAg), hepatitis B core antigen (HBcAg), and hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) in renal tissues from patients with HBV-related glomerulonephritis. METHODS: Renal tissue biopsies taken from patients with HBV-related glomerulonephritis and two control groups were prepared for immunocytochemical detection of HBsAg and HBcAg. HBV cccDNA was examined using a nested PCR. RESULTS: Of the 63 HBV-related glomerulonephritis patients studied, HBsAg was present in the renal tissues of 48 (76.2%) and HBcAg in the renal tissues of 27 (42.9%). The HBsAg and HBcAg positive rates in HBV-related glomerulonephritis patients were higher than those of the 20 patients with non-HBV-related glomerulonephritis (p<0.05). However, there was no significant difference when the HBV-related glomerulonephritis patients were compared with 12 patients with renal tuberculosis, renal atrophy, renal calculus, and renal tumor with positive serum HBV markers. In patients with HBV-related glomerulonephritis, there was no significant difference in HBsAg and HBcAg positive rates in renal tissue between patients with and without serum hepatitis B e antigen (HBeAg). By nested PCR, two of five patients with HBV-related glomerulonephritis were positive for HBV cccDNA. CONCLUSION: The location and replication of HBV in renal tissue make the kidney a potential reservoir for HBV. HBV cccDNA may be key in the search for anti-HBV drugs.


Asunto(s)
ADN Viral/aislamiento & purificación , Glomerulonefritis/virología , Antígenos de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/virología , Adolescente , Adulto , Estudios de Casos y Controles , ADN Circular/aislamiento & purificación , Femenino , Glomerulonefritis/sangre , Antígenos de la Hepatitis B/sangre , Virus de la Hepatitis B , Hepatitis B Crónica/sangre , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Replicación Viral , Adulto Joven
12.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 26(supl.7): 32-38, mayo 2008. ilus
Artículo en Es | IBECS | ID: ibc-71306

RESUMEN

Hay al menos 4 análogos de los nucleótidos/nucleósidos aprobados para el tratamiento de la hepatitis crónica por virus de la hepatitis B (HBC): lamivudina, adefovir dipivoxil, entecavir y telbivudina. La introducción de estos fármacos ha supuesto un cambio radical en el tratamiento de esta enfermedad. Las ventajas de estos fármacos son la administración oral, la excelente tolerancia y la eficacia en todos los tipos de HBC (enfermedad hepática compensada y descompensada). Las limitaciones son la necesidad de tratamientos prolongados que dificultan la adhesión y pueden ocasionar la selección de cepas del virus de la hepatitis B resistentes a los distintos fármacos. La tasa de resistencias es diferente para cada uno de los fármacos. Los análogos de nucleótidos, como el adefovir y el tenofovir, son útiles en pacientes con resistencia a análogos de nucleósidos, como lamivudina, entecavir y telbivudina, y viceversa. En casos de resistencia a uno de estos fármacos se aconseja el tratamiento combinado


At least 4 nucleos(t)ide analogs have been approved for the treatment of chronic hepatitis B: lamivudine, adefovir dipivoxil, entecavir, and telbivudine. The introduction of these drugs has radically changed the treatment of this disease. The advantages of these drugs are their oral administration, excellent tolerability and efficacy in all types of chronic hepatitis B (compensated and decompensated disease). The limitations are the need for prolonged treatments, which hampers adherence and can cause selection of HBV strains resistant to distinct drugs. The resistance rate differs for each of the drugs. Nucleotide analogs such as adefovir and tenofovir are useful in patients resistant to nucleoside analogs such as lamivudine, entecavir and telbivudine and vice versa. In cases of resistance to one of these drugs, combined treatment is advised


Asunto(s)
Humanos , Hepatitis B Crónica/tratamiento farmacológico , Nucleósidos/agonistas , Nucleótidos/agonistas , Antivirales/uso terapéutico , Lamivudine/uso terapéutico , Antígenos de la Hepatitis B/aislamiento & purificación
13.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 26(supl.7): 39-48, mayo 2008. ilus, tab
Artículo en Es | IBECS | ID: ibc-71307

RESUMEN

La hepatitis crónica por virus de la hepatitis B continúa siendo un grave problema de salud mundial. El hecho de que una alta carga viral se relacione con una mayor progresión a cirrosis y hepatocarcinoma en estos pacientes hace necesaria la búsqueda de nuevos fármacos que logren una rápida, potente y duradera supresión de la replicación viral. El entecavir es un nuevo antiviral muy potente que ha demostrado, en estudios en fase II y III, su superioridad con respecto a placebo y lamivudina en los pacientes infectados de forma crónica por el virus de la hepatitis B, en términos de mejoría histológica, eficacia para lograr la supresión de la replicación viral y normalización de la cifra de transaminasas. Su tolerabilidad es buena, ya que sus efectos secundarios, en su mayoría, suelen ser leves o moderados, con una incidencia de aparición similar a la encontrada con placebo o lamivudina. Además, en pacientes naïve no se ha objetivado la aparición de resistencias tras 3 años de tratamiento. Sin embargo, en pacientes con resistencia previa a lamivudina, la incidencia de las recidivas alcanza en torno al 15% a los 3 años. Se necesitan más estudios que lo comparen con las otras opciones terapéuticas disponibles en la actualidad, así como ensayos a más largo plazo para evaluar su seguridad, pero parece que el entecavir va ocupar un lugar preponderante en el tratamiento de los pacientes crónicamente infectados por el virus de la hepatitis B


Chronic hepatitis B continues to be a serious problem worldwide. Because a high viral load is associated with greater progression to cirrhosis and hepatocarcinoma in these patients, new drugs that achieve rapid, potent and lasting suppression of viral replication must be sought. Entecavir is a new, highly potent antiviral agent; phase II and III studies have demonstrated this drug to be superior to placebo and lamivudine in patients with chronic hepatitis B virus in terms of histological improvement, efficacy in achieving suppression of viral replication and normalizing transaminase counts. The drug is well tolerated, since its adverse effects are usually mild or moderate and their incidence is similar to that found with placebo or lamivudine. Moreover, in treatment-naïve patients, no resistance has been observed after 3 years of therapy. However, in patients with prior resistance to lamivudine, the incidence of resistance is approximately 15% at 3 years. Further studies are required that compare this drug with other currently available therapeutic options, as well as longer term trials to evaluate its safety. It seems that entecavir will occupy a major place in the treatment of patients with chronic hepatitis B virus infection


Asunto(s)
Humanos , Hepatitis B Crónica/tratamiento farmacológico , Antivirales/uso terapéutico , Farmacorresistencia Viral , Lamivudine/uso terapéutico , Antígenos de la Hepatitis B/aislamiento & purificación
14.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 25(5): 317-323, mayo 2007. tab
Artículo en Es | IBECS | ID: ibc-056898

RESUMEN

Introducción. Las hepatitis virales constituyen uno de los principales problemas sociosanitarios y económicos a nivel mundial por lo que precisan un estrecho control epidemiológico. Métodos. En el presente trabajo estudiamos la seroprevalencia de las hepatitis virales una muestra representativa de la población de una zona básica de salud urbana en Valladolid (España). Resultados. La prevalencia de anticuerpos anti-VHA (AcVHA) fue del 52%, de HBcAc del 8,2%, de AcVHC del 1,1%, de AcVHE 0,8% y AcVHG 5,8%. La prevalencia de AcVHA, HBcAc y AcVHG aumenta significativamente con la edad (p < 0,005 en todos los casos). En menores de 20 años la prevalencia de AcVHA es del 3,8%, HBcAc < 0,28% y AcVHG 1,3%. En el grupo de edad de 20-39 años, la seroprevalencia frente al VHA se asocia con niveles educativos bajos (p 5 0,009) y con el nacimiento en otras provincias (p 5 0,016). La seroprevalencia de HBcAc se asocia principalmente con hospitalizaciones anteriores a 1990 (p 5 0,002; OR: 3,32 [1,48-7,42]), realización del servicio militar obligatorio anterior a 1990 (p < 0,0001; OR: 37,33 [3,68-378,03]) y prácticas de acupuntura (p 5 0,018; OR: 57,75 [26,17-127,42]). La seroprevalencia frente a VHG se asocia con hospitalizaciones antes de 1990 (p 5 0,019; OR: 2,969 [1,154-7,639]). Los seropositivos frente a VHC tenían antecedentes de transfusiones (2 casos) hospitalización (1 caso) o drogadicción (1 caso). De los seropositivos frente a VHE sólo un caso tenía antecedentes de viaje a zona endémica para VHE. Conclusiones. Nuestro estudio muestra que las seroprevalencias de las hepatitis virales en una muestra representativa de población urbana de Castilla y León son similares a las seroprevalencias obtenidas en el resto de España y de los países desarrollados, inferior a la observada en los estudios realizados en España en los últimos 20 años consecuencia de las medidas profilácticas adoptadas (AU)


Introduction. Viral hepatitis is a major social, health and economic problem worldwide, requiring strict epidemiological control. Methods. This study presents the viral hepatitis seroprevalence in a representative sample from an urban health care area in Valladolid (Spain). Results. Antibody prevalence was as follows: anti-HAV 52%; anti-HBc, 8.2%; anti-HCV, 1.1%; anti-HEV, 0.8%; and anti-HGV 5.8%. Prevalence of anti-HAV, anti-HBc and anti-HGV increased significantly with age (P < 0.005 in all cases). In individuals younger than 20, prevalence of anti-HAV was 3.8%, anti-HBc < 0.28% and anti-HGV 1.3%. In the 20-39 year-old group, seroprevalence against HAV was associated with low educational levels (P 5 0.009) and with birth in other provinces (P 5 0.016). Anti-HBc seroprevalence was mainly associated with three factors: prior hospitalization before 1990 (P 5 0.002; OR 3.32 [1.48-7.42]); compulsory military service before 1990 (P < 0.0001; OR 37.33 [3.68-378.03]); and acupuncture treatments (P 5 0.018; OR 57.75 [26.17-127.42]). Seroprevalence against HGV was associated with hospitalizations before 1990 (P 5 0.019; OR 5 2.969 [1.154-7.639]). Seropositive status to HCV revealed a transfusion history (2 cases), hospitalization (1 case) or drug addiction (1 case). Only one case among those seropositive to HEV had a history of a prior trip to a HEV-endemic area. Conclusions. Our study shows that the seroprevalences of viral hepatitis in a representative sample of urban population of Castille and Leon are similar to the seroprevalences observed in the rest of Spain and other developed countries, lower than the ones observed in the studies performed in Spain in the last 20 years due to the measures of prophylaxis that werw taken (AU)


Asunto(s)
Humanos , Hepatitis Viral Humana/epidemiología , Estudios Seroepidemiológicos , Virus de Hepatitis/aislamiento & purificación , Antígenos de la Hepatitis C/aislamiento & purificación , Antígenos de Hepatitis A/aislamiento & purificación , Antígenos de Hepatitis delta/aislamiento & purificación , Antígenos de la Hepatitis B/aislamiento & purificación
15.
Protein Expr Purif ; 49(2): 168-75, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16829133

RESUMEN

The current HBsAg vaccine has performed a vital role in preventing the transmission of HBV during the past 20 years. However, a number of individuals still show no response or a low response to the vaccine. In the present study, the HBV envelope large protein gene was cloned into the eukaryotic expression vector pPIC9k and was subsequently expressed in the yeast Pichia pastoris. The HBV large protein (L protein) was produced and secreted into the medium, where some of the L protein formed particles. The soluble L protein and particles were purified by column chromatography and sucrose density gradient centrifugation. Western blot analysis demonstrated that the particle was composed of both HBV L and S protein. To compare the antigenicity of the L protein and HBsAg, rabbits were immunized with the soluble L protein and the commercially available HBV vaccine and the increasing level of antibodies was determined by ELISA. The results showed that the anti-HBsAg antibody, from rabbits injected with the L protein at a dose of 2 and 10microg, was detected on day 14, whereas rabbits vaccinated with 10 and 2microg HBsAg did not develop antibodies until day 21 and 28, respectively. The antibody level in groups inoculated with the L protein was approximately 50% higher than in the group injected with HBsAg using the same dose. Furthermore, 2microg L protein induced a significant and rapid anti-HBsAg antibody response than 10microg HBsAg. Therefore, we suggest that the L protein is an ideal candidate for a new generation HB vaccine to protect people from HBV infection.


Asunto(s)
Vacunas contra Hepatitis B/genética , Vacunas contra Hepatitis B/aislamiento & purificación , Virus de la Hepatitis B/genética , Pichia , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/aislamiento & purificación , Animales , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos/inmunología , Relación Dosis-Respuesta Inmunológica , Hepatitis B/genética , Hepatitis B/inmunología , Hepatitis B/prevención & control , Antígenos de la Hepatitis B/biosíntesis , Antígenos de la Hepatitis B/genética , Antígenos de la Hepatitis B/inmunología , Antígenos de la Hepatitis B/aislamiento & purificación , Antígenos de la Hepatitis B/farmacología , Vacunas contra Hepatitis B/biosíntesis , Vacunas contra Hepatitis B/inmunología , Vacunas contra Hepatitis B/farmacología , Virus de la Hepatitis B/inmunología , Humanos , Inmunización , Pichia/genética , Conejos , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/farmacología , Factores de Tiempo , Proteínas del Envoltorio Viral/biosíntesis , Proteínas del Envoltorio Viral/inmunología , Proteínas del Envoltorio Viral/farmacología
16.
Hepatology ; 43(3): 539-47, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16496321

RESUMEN

Dendritic cells (DC) of hepatitis B virus (HBV) carriers have been reported to exhibit functional impairment. Possible explanations for this phenomenon are infection of HBV by DC or alteration of DC function by HBV. We therefore analyzed whether DC support the different steps of HBV infection and replication: uptake, deposition of the HBV genome in the nucleus, antigen expression, and progeny virus release. When HBV genomes were artificially introduced into monocyte-derived DC by adenoviral vectors, low-level expression of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) but no HBV replication was detected. When monocyte-derived DC were subjected to wild-type HBV or a recombinant HBV expressing Renilla luciferase under a non-liver-specific promoter, intracellular HBV DNA was detected in a low percentage of cells. However, neither nuclear cccDNA was formed nor luciferase activity was detected, indicating that either uncoating or nucleocytoplasmic transport were blocked. To verify our observation in the in vivo situation, myeloid and plasmacytoid DC were isolated from blood of high viremic HBV carriers, and analyzed by quantitative polymerase chain reaction (PCR) and electron microscopy. Although circulating DC had in vivo been exposed to more than 10(4) HBV virions per cell, HBV genomic DNA was hardly detected, and no nuclear cccDNA was detected at all. By using electron microscopy, subviral particles were found in endocytic vesicles, but virions were undetectable as were viral capsids in the cytoplasm. In conclusion, circulating DC may take up HBV antigens, but neither support nucleocytoplasmic transport nor replication of HBV.


Asunto(s)
Células Dendríticas/virología , Antígenos de la Hepatitis B/aislamiento & purificación , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis B/inmunología , Adenoviridae , Portador Sano , Células Cultivadas , Células Dendríticas/inmunología , Expresión Génica , Técnicas de Transferencia de Gen , Vectores Genéticos , Hepatitis B/genética , Humanos , Virión/genética , Virión/inmunología , Replicación Viral/genética , Replicación Viral/inmunología
17.
Rev Inst Med Trop Sao Paulo ; 44(6): 331-4, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12532217

RESUMEN

The presence of serological markers for hepatitis B virus (HBsAg, anti-HBc IgM and Anti-HBc total) was investigated in the serum of 1,396 individuals who had clinical suspect of hepatitis. It was observed that 50.7% of the individuals were positive and, from the total of the studied individuals, 14.5% were positive for HBsAg. From these, 8.5% were also positive for anti-HBc IgM. The analysis in relation to gender showed a higher seroprevalence index among male individuals (p < 0.0001). It was observed the occurrence of subtypes adw2 (62.7%), ayw3 (23.5%), ayw2 (9.8%) and adw4 (3.9%). The viral DNA was detected in 61 (33.9%) HBsAg positive samples and in one sample positive only for anti-HBc total. These results indicate an important incidence of the HBV infection in this population, and reinforce previous studies regarding this virus in the central west region of Brazil.


Asunto(s)
ADN Viral/aislamiento & purificación , Virus de la Hepatitis B/genética , Hepatitis B/epidemiología , Biomarcadores/sangre , Brasil/epidemiología , Femenino , Hepatitis B/sangre , Anticuerpos contra la Hepatitis B/aislamiento & purificación , Antígenos de la Hepatitis B/aislamiento & purificación , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/inmunología , Humanos , Masculino , Estudios Seroepidemiológicos , Serotipificación
18.
Virus Res ; 74(1-2): 59-73, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11226575

RESUMEN

The hepatitis B virus protein HBx has been implicated in the development of liver cancer. It has been shown that the HBx protein is able to bind to single-stranded DNA in a specific manner. This DNA binding activity might be relevant for HBx oncogene character. To study the HBx interaction with nucleic acids in more detail we expressed full-length HBx as well as several N- and C-terminally truncated HBx proteins as 6xHis and GST-fusions in E. coli. Using a gel shift assay, we were able to demonstrate that all of the truncated HBx proteins have the ability to bind to an AU-rich RNA. The affinity of GST-HBx #3 (residues 80-142) was an order of magnitude higher than that of GST-HBx #2 (residues 5-79), indicating that a high affinity RNA binding site is located in HBx C-terminal half. AUF1 is the protein ligand that binds to AU-rich RNA regions present in certain proto-oncogene mRNAs and causes their rapid degradation. By a competitive binding experiment of AUF1 and HBx to the AU-rich RNA oligonucleotide, we show that HBx is able to displace AUF1 from its binding site on the RNA oligonucleotide. This new aspect of HBx function is discussed in the context of cellular transformation.


Asunto(s)
Antígenos de la Hepatitis B/metabolismo , Virus de la Hepatitis B/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo D , Proteínas de Unión al ARN/metabolismo , ARN/metabolismo , Transactivadores/metabolismo , Sitios de Unión , Unión Competitiva , Cromatografía de Afinidad , Clonación Molecular , Electroforesis en Gel de Poliacrilamida , Enteropeptidasa/metabolismo , Escherichia coli , Expresión Génica , Vectores Genéticos , Antígenos de la Hepatitis B/genética , Antígenos de la Hepatitis B/aislamiento & purificación , Virus de la Hepatitis B/genética , Hepatitis B Crónica/epidemiología , Ribonucleoproteína Nuclear Heterogénea D0 , Reacción en Cadena de la Polimerasa , Unión Proteica , Sondas ARN/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/aislamiento & purificación , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Eliminación de Secuencia , Transactivadores/genética , Transactivadores/aislamiento & purificación , Proteínas Reguladoras y Accesorias Virales
19.
Commun Dis Public Health ; 3(2): 141-2, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10902261

RESUMEN

False positive hepatitis B surface and e antigen results on the Abbott Axsym analyser are causing concern. All users of this technology should be aware of the problem.


Asunto(s)
Antígenos de la Hepatitis B/aislamiento & purificación , Hepatitis B/diagnóstico , Inmunoensayo/normas , Tamizaje Masivo/instrumentación , Tamizaje Masivo/normas , Reacciones Falso Positivas , Hepatitis B/inmunología , Humanos , Juego de Reactivos para Diagnóstico/normas , Sensibilidad y Especificidad , Reino Unido
20.
Br J Cancer ; 80(1-2): 59-66, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10389978

RESUMEN

The major risk factors for hepatocellular carcinomas (HCC) in high incidence areas include infection with hepatitis B and C viruses (HBV, HCV) and exposure to aflatoxin. Genetic alterations in 24 liver resection specimens from Shanghai and Qidong were studied. Hepatitis B virus was integrated in all patient samples, and a null phenotype for the GSTM1 enzyme was present in 63% of patients. Alteration of p53 was present in 95% (23/24) of cases: mutations of the p53 gene in 12 HCC, p53 overexpression in 13 and loss of heterozygosity (LOH) of chromosome 17p in 17. All seven HCCs with a p53 mutation from Qidong and three of five from Shanghai had the aflatoxin-associated point mutation with a G to T transversion at codon 249, position 3. No HCC had microsatellite instability. LOH of chromosome 4q, 1p, 16q and 13q was present in 50%, 46%, 42% and 38%, respectively, and 4q was preferentially lost in HCCs containing a p53 mutation: LOH of 4q was present in 75% (9/12) of HCC with, but only 25% (3/12) of HCC without, a p53 gene mutation (P = 0.01). These data indicate a possible interaction between p53 gene mutation and 4q loss in the pathogenesis of HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Cromosomas Humanos Par 4/genética , Genes p53 , Neoplasias Hepáticas/genética , Pérdida de Heterocigocidad , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/virología , China , Cromosomas Humanos Par 17/genética , ADN/análisis , Epóxido Hidrolasas/genética , Genes p53/genética , Glutatión Transferasa/genética , Hepatitis B/complicaciones , Hepatitis B/diagnóstico , Antígenos de la Hepatitis B/aislamiento & purificación , Antígenos de la Hepatitis C/aislamiento & purificación , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/virología , Repeticiones de Microsatélite , Mutación , Reacción en Cadena de la Polimerasa
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