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1.
J Gastroenterol ; 44(6): 568-76, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19370306

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) causes one of the most important chronic viral infections worldwide. HBV is classified into eight genotypes whose epidemiology varies geographically. In Brazil, genotypes A, D, and F are more frequent, while in East Asia, genotypes B and C predominate. Several studies showed that immigrants retain the HBV infection pattern of their ancestral country. PURPOSE: To identify HBV genotypes infecting chronic carriers in Brazilian families of Western and Asian descent by Hepatitis B surface antigen gene sequencing and analyze the route of viral transmission by phylogenetic analysis of viral sequences. METHODS: Eighty-seven people chronically infected with HBV were separated into two groups: Western descent (27) and Asian descent (60). Surface and pre-core/core genes were amplified from serum HBV-DNA and sequences were subjected to phylogenetic analysis. RESULTS: HBV genotype A was found in 74% of Western subjects, while genotype C was found in 94% of Asian patients. Thirty-eight percent of Western families were infected with HBV with similar pre-core/core sequences, while only 25% of Asian families showed similarity in these sequences. CONCLUSIONS: Phylogenetical analysis of pre-core/core HBV gene suggested intra-familial transmission of HBV in 38% of Western families and 25% of Asian families. Analysis of HBsAg gene sequences helped to define the HBV genotype but did not allow inferring route of transmission as its sequences showed a smaller phylogenetic signal than pre-core/core sequences. Chronic HBV carriers of Asian descent born in or living in Brazil were infected with the same HBV genotype predominant in their ancestral country.


Asunto(s)
Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Filogenia , Adulto , Asia/etnología , Brasil/epidemiología , Europa (Continente)/etnología , Femenino , Genotipo , Hepatitis B Crónica/genética , Humanos , Masculino , Estudios Seroepidemiológicos , Adulto Joven
2.
J Gastroenterol ; 37(9): 732-6, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12375147

RESUMEN

BACKGROUND: The aim of this study was to evaluate an alternative treatment (consensus interferon plus ribavirin) for chronic hepatitis C patients resistant to combined therapy. METHODS: Fourteen patients previously resistant to interferon alpha plus ribavirin were consecutively assigned to receive 15 microg of consensus interferon plus ribavirin (1000 mg) daily for 4 weeks, and 9-15 microg every other day plus daily ribavirin for the following 44 weeks. Alanine aminotransferase and hepatitis C virus (HCV) RNA (Amplicor Monitor; Roche) levels were monitored during therapy and for 24 weeks after its completion. RESULTS: A rapid and marked decrease of HCV RNA viremia of more than 2 logs was observed in 10 (71%) of 14 patients at week 2 of treatment. At the end of therapy, 10 (71%) of 14 patients had undetectable HCV RNA. The end-of-treatment response rates were 6 of 9 (67%) patients for genotype 1 and 4 of 5 (80%) for other genotypes. Sustained response was observed in 4 (36%) of 11 patients who completed 24 weeks of follow-up. CONCLUSIONS: A marked and rapid decrease of viral load was observed during therapy with high doses of consensus interferon plus ribavirin in patients previously resistant to combined therapy, even in those infected with genotype 1. Of 11 patients who completed the post-treatment follow-up, 36% presented a sustained response.


Asunto(s)
Antivirales/administración & dosificación , Antivirales/uso terapéutico , Farmacorresistencia Viral Múltiple , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Interferón Tipo I/administración & dosificación , Interferón Tipo I/uso terapéutico , Interferón-alfa/administración & dosificación , Interferón-alfa/uso terapéutico , Ribavirina/administración & dosificación , Ribavirina/uso terapéutico , Adulto , Alanina Transaminasa/sangre , Alanina Transaminasa/efectos de los fármacos , Quimioterapia Combinada , Femenino , Hepatitis C Crónica/sangre , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Proteínas Recombinantes , Factores de Tiempo , Carga Viral
3.
BMC Fam Pract ; 5: 7, 2004 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-15084223

RESUMEN

BACKGROUND: Clinical studies for testing new drugs against hepatitis B ought to be carried out in low prevalence areas despite difficulties on patient recruitment. In such areas, relatives of chronic hepatitis B patients are considered to be at risk of acquiring the hepatitis B virus (HBV). The aim of this study was to evaluate the prevalence of HBV markers (anti-HBc, HBsAg and anti-HBs) in familial members of chronic hepatitis B (CHB) patients according to their origin (Asian or Western) in a low prevalence area, the city of São Paulo, Brazil. METHODS: Twenty three Asian CHB probands and their 313 relatives plus 31 CHB probands of Western origin and their 211 relatives were screened for HBV serological markers; the study was carried out in the outpatient clinic of the University of São Paulo School of Medicine. RESULTS: Mother to child transmission was greater in the Asian group whereas sexual transmission was more frequent in the Western group (p < 0.0001). Anti-HBc was positive in 90% and 57% of the Asian and Western parents (p = 0.0432) and in 97% and 33% of the Asian and Western brothers (p = 0.0001), respectively. HBsAg was more frequent among the Asian (66%) than the Western (15%) mothers (p = 0.0260) as well as among the Asian (81%) than the Western (19%) brothers (p = 0.0001). We could detect 110 new HBsAg-positive subjects related to the 54 index patients, being the majority (81%) of Asian origin. CONCLUSION: In low prevalence area of hepatitis B, family members and household contacts of chronic HBV carriers are at high risk for acquiring hepatitis B.


Asunto(s)
Pueblo Asiatico/estadística & datos numéricos , Portador Sano/sangre , Relaciones Familiares , Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/etnología , Población Blanca/estadística & datos numéricos , Adulto , Brasil/etnología , Portador Sano/diagnóstico , ADN Viral/sangre , Transmisión de Enfermedad Infecciosa/estadística & datos numéricos , Femenino , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/transmisión , Humanos , Técnicas para Inmunoenzimas , Masculino , Selección de Paciente , Prevalencia , Factores de Riesgo , Estudios Seroepidemiológicos
4.
Rev Inst Med Trop Sao Paulo ; 46(1): 25-31, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15057330

RESUMEN

UNLABELLED: Hepatocellular carcinoma (HCC) is an important type of cancer etiologically related to some viruses, chemical carcinogens and other host or environmental factors associated to chronic liver injury in humans. The tumor suppressor gene p53 is mutated in highly variable levels (0-52%) of HCC in different countries. OBJECTIVE: The objective of the present study was to compare the frequency of aberrant immunohistochemical expression of p53 in HCC occurring in cirrhotic or in non-cirrhotic patients as well as in liver cell dysplasia and in adenomatous hyperplasia. We studied 84 patients with HCC or cirrhosis. RESULTS: We detected p53 altered immuno-expression in 58.3% of patients in Grade III-IV contrasting to 22.2% of patients in Grade I-II (p = 0.02). Nontumorous areas either in the vicinity of HCC or in the 30 purely cirrhotic cases showed no nuclear p53 altered expression, even in foci of dysplasia or adenomatous hyperplasia. No significant difference was found among cases related to HBV, HCV or alcohol. CONCLUSION: The high frequency of p53 immunoexpression in this population is closer to those reported in China and Africa, demanding further studies to explain the differences with European and North American reports.


Asunto(s)
Carcinoma Hepatocelular/química , Fibrosis/metabolismo , Neoplasias Hepáticas/química , Proteína p53 Supresora de Tumor/análisis , Biomarcadores/análisis , Carcinoma Hepatocelular/patología , Fibrosis/patología , Humanos , Hiperplasia/metabolismo , Hiperplasia/patología , Inmunohistoquímica , Hígado/metabolismo , Hígado/patología , Neoplasias Hepáticas/patología
5.
Rev Inst Med Trop Sao Paulo ; 51(5): 261-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19893978

RESUMEN

BACKGROUND: The quantitation of serum HBeAg is not commonly used to monitor viral response to therapy in chronic hepatitis B. METHODS: In this study, 21 patients receiving varying therapies were followed and their viral response monitored by concomitant viral load and HBeAg quantitation in order to study the meaning and the kinetics of both parameters. RESULTS: It was possible to distinguish between three different patterns of viral response. The first was characterized by a simultaneous decrease in serum HBV DNA and HBeAg. The second pattern was characterized by a decrease in serum HBeAg but persistent detection of HBV DNA. The third pattern was characterized by undetectable HBV DNA with persistent HBeAg positivity, which points to a non-response (Pattern III-B) except when HBeAg levels showed a slow but steady drop, characterizing a 'slow responder' patient (Pattern III-A). CONCLUSIONS: The first pattern is compatible with a viral response. A long-term HBeAg seropositivity with a slow and persistent decrease (Pattern III-A) is also compatible with a viral response and calls for a prolongation of anti-viral treatment.


Asunto(s)
ADN Viral/sangre , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B , Hepatitis B Crónica/sangre , Hepatitis B Crónica/tratamiento farmacológico , Adulto , Anciano , Antivirales/uso terapéutico , Niño , Farmacorresistencia Viral , Femenino , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/inmunología , Antígenos e de la Hepatitis B/inmunología , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Retratamiento , Carga Viral , Adulto Joven
6.
World J Gastroenterol ; 14(16): 2522-8, 2008 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-18442199

RESUMEN

AIM: To evaluate the epidemiological, clinical, laboratory and histological variables capable of predicting the progression of hepatic structural disturbances in chronic hepatitis C patients during the time interval between two liver biopsies. METHODS: Clinical charts of 112 chronic hepatitis C patients were retrospectively analyzed, whereas liver biopsies were revised. Immunohistochemical detection of interferon receptor was based on the Envision-Peroxidase System. RESULTS: In the multivariate analysis, the variables in the age at first biopsy, ALT levels, presence of lymphoid aggregates and siderosis were the determinants of the best model for predicting the severity of the disease. The direct progression rate of hepatic structural lesions was significantly higher in untreated patients, intermediate in treated non-responders and lower in treated responders to antiviral therapy (non-treated vs responders, 0.22 +/- 0.50 vs -0.15 +/- 0.46, P = 0.0053). Immuno-expression of interferon receptor is not a relevant factor. CONCLUSION: The best predictors of the progression of fibrosis are age at the first liver biopsy, extent of ALT elevation, inflammation at liver histology and hepatic siderosis. Antiviral treatment is effective in preventing the progression of liver structural lesions in chronic hepatitis C patients.


Asunto(s)
Hepatitis C Crónica/patología , Adulto , Biopsia , Progresión de la Enfermedad , Femenino , Hepatitis C Crónica/etiología , Hepatitis C Crónica/fisiopatología , Humanos , Inmunohistoquímica , Cirrosis Hepática/patología , Cirrosis Hepática/fisiopatología , Cirrosis Hepática/virología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Receptores de Interferón/metabolismo , Análisis de Regresión
7.
Dig Dis Sci ; 51(8): 1413-9, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16868833

RESUMEN

The aim of this study was to compare portal and splenic blood flows and the liver morphology in hepatosplenic (HS) and hepatointestinal (HI) schistosomiasis. Doppler ultrasound measurements were performed in 48 adult patients with schistosomiasis, according to the criteria of the World Health Organization, and compared with those performed in 20 healthy controls. Portal flow was significantly higher (P < 0.0001) in both HS and HI (2481 +/- 1467 and 2159 +/- 1446 ml/min, respectively) than in normal individuals (842 +/- 322 ml/min). There was no difference in splenic blood flow (822 +/- 685 and 458 +/- 292 ml/min, respectively) between HS and HI, but these values were significantly higher than those of normal controls (243 +/- 94 ml/min). Portal and splenic overflow are found in both the HS and the HI forms of schistosomiasis.


Asunto(s)
Hipertensión Portal/fisiopatología , Parasitosis Intestinales/fisiopatología , Circulación Hepática/fisiología , Parasitosis Hepáticas/fisiopatología , Esquistosomiasis mansoni/fisiopatología , Enfermedades del Bazo/fisiopatología , Ultrasonografía Doppler , Adulto , Animales , Velocidad del Flujo Sanguíneo/fisiología , Heces/parasitología , Femenino , Humanos , Hipertensión Portal/diagnóstico por imagen , Hipertensión Portal/etiología , Parasitosis Intestinales/complicaciones , Parasitosis Intestinales/diagnóstico por imagen , Parasitosis Hepáticas/complicaciones , Parasitosis Hepáticas/diagnóstico por imagen , Masculino , Schistosoma mansoni/aislamiento & purificación , Esquistosomiasis mansoni/complicaciones , Esquistosomiasis mansoni/diagnóstico por imagen , Enfermedades del Bazo/diagnóstico por imagen , Enfermedades del Bazo/parasitología
8.
World J Gastroenterol ; 12(45): 7271-7, 2006 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-17143940

RESUMEN

AIM: To evaluate the impact of hepatitis C virus (HCV) infection with genotype 1 or 3 and the presence or absence of liver cirrhosis (LC) in the early viral kinetics response to treatment. METHODS: Naive patients (n = 46) treated with interferon-alpha (IFN-alpha) and ribavirin and followed up with frequent early HCV-RNA determinations were analysed. Patients were infected with genotype 1 (n = 28, 7 with LC) or 3 (n = 18, 5 with LC). RESULTS: The first phase decline was larger in genotype 3 patients than in genotype 1 patients (1.72 vs 0.95 log IU/mL, P < 0.001). The second phase slope decline was also larger in genotype 3 patients than in genotype 1 patients (0.87 vs 0.15 log/wk, P < 0.001). Differences were found in both cirrhotic and non-cirrhotic patients. Genotype 1 cirrhotic patients had a slower 2nd phase slope than non-cirrhotic patients (0.06 vs 0.18 log/wk, P < 0.02). None of genotype 1 cirrhotic patients had a 1st phase decline larger than 1 log (non-cirrhotic patients: 55%, P < 0.02). A similar trend toward a slower 2nd phase slope was observed in genotype 3 cirrhotic patients but the 1st phase slope decline was not different. Sustained viral response was higher in genotype 3 patients than in genotype 1 patients (72% vs 14%, P < 0.001) and in genotype 1 non-cirrhotic patients than in genotype 1 cirrhotic patients (19% vs 0%). A second phase decline slower than 0.3 log/wk was predictive of non-response in all groups. CONCLUSION: Genotype 3 has faster early viral decline than genotype 1. Cirrhosis correlates with a slower 2nd phase decline and possibly with a lower 1st phase slope decline in genotype 1 patients.


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Cirrosis Hepática/virología , Ribavirina/uso terapéutico , Brasil , Esquema de Medicación , Quimioterapia Combinada , Genotipo , Hepacivirus/clasificación , Hepacivirus/efectos de los fármacos , Humanos , Cinética , Cirrosis Hepática/tratamiento farmacológico , ARN Viral/sangre , Carga Viral
9.
J Clin Microbiol ; 42(6): 2455-60, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15184419

RESUMEN

A method for genotyping hepatitis B virus by partial HBsAg gene sequencing with primers common to all known genotypes was developed. Mutations related to anti-HBs resistance are also detected with this method. Samples from 103 Brazilian patients were analyzed. Precore and core region of these viruses were also sequenced in 101 patients. Genotypes A, B, C, D, and F were found with frequencies of 49.5, 2.9, 13.6, 24.3, and 9.7%, respectively. Genotypes B and C were found only in Asian patients, whereas genotypes A, D, and F were more common in patients without an Asian background. Precore mutants were found in 32 (31.7%) of 101 patients, with a higher frequency in those infected with genotype D (22 of 25 [88.0%]). Analysis of nucleotide 1858 showed presence of thymine in all patients with genotypes B, C, and D and in a few patients with genotypes A (10.0%) and F (30.0%), who showed more frequently the presence of cytosine. This nucleotide was closely related to the presence of precore mutants. Mutations in the basal core promoter were found in 64 of 101 (63.4%) samples. These mutations were more frequent in patients infected with genotype F (90.0%) and less frequent in patients infected with genotype B (33.3%). Deletions in this region were found in two genotype C-infected patients.


Asunto(s)
Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Mutación , Secuencia de Aminoácidos , Femenino , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Humanos , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas , Análisis de Secuencia de ADN
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