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2.
Sci Rep ; 10(1): 6708, 2020 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-32317697

RESUMEN

Hepatitis B virus (HBV) infection is still a concern in vulnerable populations. In a study performed by our team in 1999-2003 in two Afro-Brazilian communities, Furnas dos Dionísios (FD) and São Benedito (SB), high prevalence rates of HBV exposure (42.7% and 16.0%, respectively), high susceptibility to HBV (55.3% and 63.0%) and low HBV vaccination like profile rates (2.0% and 21.0%) were observed. In 2015-2016, we reassessed HBV epidemiological and molecular features in these two communities to verify the impact of health actions adopted in the last years. The prevalence rate of HBV exposure among the enrolled 331 subjects was 35.3% in FD and 21.8% in SB. HBV chronic infection (5.8% in FD, 4.9% in SB) remained high. The rate of HBV vaccination like profile increased from 10.7% to 43.5% (2.0% to 45.9% in FD, 21.0% to 39.5% in SB) while susceptible subjects declined from 58.9% to 26.3% (55.3% to 18.8% in FD, 63.0% to 38.7% in SB). Among 18 HBsAg positive samples, 13 were successfully sequenced (pre-S/S region). Phylogenetic analyses showed that all isolates belong to HBV subgenotype A1, clustering within the Asian-American clade. Despite the maintenance of high prevalence rate of HBV exposure over these 13 years of surveillance, significant improvements were observed, reinforcing the importance of facilitated HBV vaccination to difficult-to-access population to close gaps in prevention.


Asunto(s)
Población Negra , Hepatitis B/epidemiología , Adolescente , Adulto , Asiático , Conducta , Biomarcadores/sangre , Brasil/epidemiología , Niño , Preescolar , Demografía , Femenino , Hepatitis B/sangre , Hepatitis B/inmunología , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/fisiología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Filogenia , Prevalencia , Vacunación , Adulto Joven
3.
PLoS One ; 10(8): e0135816, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26275046

RESUMEN

Hepatitis B virus genotype A1 (HBV/A1), of African origin, is the most prevalent genotype in Brazil, while HBV/F predominates in the other South American countries. However, HBV/D is the most common in the three states of southern Brazil, where 'islands' of elevated prevalence, as Chapecó and other cities, have been described. In this study, 202 HBV chronic carriers attending in 2013 the viral hepatitis ambulatory of Chapecó, were investigated. In comparison with previous studies performed in the same ambulatory, a rapid aging of the HBV infected population was observed (mean age of the newly diagnosed patients increasing from 29.9 ± 10.3 years in 1996 to 44.4 ± 13.3 years in 2013), probably due to a singular vaccination schedule at Chapecó that included not only children but also adolescents. Phylogenetic and BLAST analyses (S region) classified 91 HBV isolates into genotypes A (n = 3) and D (n = 88). The majority of HBV/D isolates were closely related to D3 sequences. To understand the reasons for the absence or near absence of genotypes A and F, and how HBV/D was introduced in the south of Brazil, HBV/D infected patients were inquired about their genealogical and geographical origins. Forty-three (52%) patients have their four grandparents of Italian origin, vs. seven (8%) who have their four grandparents of Brazilian origin. At all, 65 out of 83 (78%) patients had at least one grandparent originating from Italy. Taking into consideration the fact that Italy is one of the few countries where subgenotype D3 is predominant, the results strongly suggested that HBV/D was introduced in Brazil through Italian immigration which culminated between 1870 and 1920.


Asunto(s)
Genotipo , Virus de la Hepatitis B/genética , Hepatitis B Crónica/genética , Filogenia , Adolescente , Adulto , Brasil , Emigración e Inmigración , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/epidemiología , Hepatitis B Crónica/etnología , Hepatitis B Crónica/transmisión , Humanos , Italia , Persona de Mediana Edad
4.
Rev Soc Bras Med Trop ; 40(1): 18-24, 2007.
Artículo en Portugués | MEDLINE | ID: mdl-17486248

RESUMEN

To assess the results from lamivudine treatment (100 mg or 150 mg) for chronic hepatitis B, 34 patients were followed at a clinic in Cuiabá, Mato Grosso, Central Brazil. Among them, 21 (62%) had liver cirrhosis and 24 (70%) were HBeAg-positive. The viral genotype was determined for 18 patients, among whom genotype A was the most prevalent (12). The median follow-up was 27 months (range from 7 to 64 months). Among the total, 23 (67%) presented a biochemical response after 2 to 24 months of treatment. Among the 24 HBeAg-positive subjects, 13 (54%) became HBeAg-negative during the follow-up. Among the anti-HBe-positive patients, 70% obtained normalization of aminotransferase levels. Fourteen (41%) did not present any initial biochemical or serological response or presented breakthrough. The L180M and M204V mutations were found in six of the non-responders. Four patients died after at least 21 months of lamivudine and three patients with liver cirrhosis developed liver cancer after 24 months. From the third year onwards, complications such as digestive system hemorrhage or liver cancer started to emerge. The present findings suggest that an early response to lamivudine treatment may be associated with better control over chronic hepatitis B.


Asunto(s)
Antivirales/uso terapéutico , Antígenos e de la Hepatitis B/inmunología , Hepatitis B Crónica/tratamiento farmacológico , Lamivudine/uso terapéutico , Adolescente , Adulto , Anciano , Alanina Transaminasa/metabolismo , Aspartato Aminotransferasas/metabolismo , Niño , Farmacorresistencia Viral/genética , Femenino , Estudios de Seguimiento , Genotipo , Hepatitis B Crónica/enzimología , Hepatitis B Crónica/inmunología , Humanos , Cirrosis Hepática/virología , Masculino , Persona de Mediana Edad , Factores de Tiempo , Resultado del Tratamiento , Carga Viral
5.
Rev. Soc. Bras. Med. Trop ; 40(1): 18-24, jan.-fev. 2007. tab, graf
Artículo en Portugués | LILACS | ID: lil-449163

RESUMEN

Para avaliar resultados do tratamento da hepatite B crônica com lamivudina, 100mg ou 150mg diários, foram acompanhados 34 pacientes em um serviço em Cuiabá, Mato Grosso. Entre os 34, 21 (62 por cento), eram cirróticos e 24 (70 por cento) HBeAg positivos. Genótipo viral foi determinado em 18, sendo predominante o genótipo A (12). O acompanhamento teve mediana de 27 meses (7 a 64). Do total, 23 (67 por cento) apresentaram resposta bioquímica entre dois e 24 meses de tratamento. Dos 24 pacientes com positividade para o HBeAg, 13 (54 por cento) apresentaram negativação do HBeAg durante o acompanhamento. Entre os anti-HBe positivos, 70 por cento tiveram normalização das aminotransferases. Quatorze (41 por cento) não apresentaram resposta bioquímica ou sorológica de início ou apresentaram breakthrough. Em seis dos que não responderam, foram encontradas as mutações L180M e M204V. Quatro pacientes faleceram após pelo menos 21 meses de lamivudina e três cirróticos desenvolveram hepatocarcinoma após 24 meses. A partir do terceiro ano surgiram complicações, como hepatocarcinoma ou hemorragia digestiva. Os presentes achados sugerem que resposta precoce ao tratamento com lamivudina pode estar associada a um melhor controle da hepatite B crônica.


To assess the results from lamivudine treatment (100 mg or 150 mg) for chronic hepatitis B, 34 patients were followed at a clinic in Cuiabá, Mato Grosso, Central Brazil. Among them, 21 (62 percent) had liver cirrhosis and 24 (70 percent) were HBeAg-positive. The viral genotype was determined for 18 patients, among whom genotype A was the most prevalent (12). The median follow-up was 27 months (range from 7 to 64 months). Among the total, 23 (67 percent) presented a biochemical response after 2 to 24 months of treatment. Among the 24 HBeAg-positive subjects, 13 (54 percent) became HBeAg-negative during the follow-up. Among the anti-HBe-positive patients, 70 percent obtained normalization of aminotransferase levels. Fourteen (41 percent) did not present any initial biochemical or serological response or presented breakthrough. The L180M and M204V mutations were found in six of the non-responders. Four patients died after at least 21 months of lamivudine and three patients with liver cirrhosis developed liver cancer after 24 months. From the third year onwards, complications such as digestive system hemorrhage or liver cancer started to emerge. The present findings suggest that an early response to lamivudine treatment may be associated with better control over chronic hepatitis B.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Adulto , Persona de Mediana Edad , Antivirales/uso terapéutico , Antígenos e de la Hepatitis B/inmunología , Hepatitis B Crónica/tratamiento farmacológico , Lamivudine/uso terapéutico , Alanina Transaminasa/metabolismo , Aspartato Aminotransferasas/metabolismo , Farmacorresistencia Viral/genética , Estudios de Seguimiento , Genotipo , Hepatitis B Crónica/enzimología , Hepatitis B Crónica/genética , Hepatitis B Crónica/inmunología , Cirrosis Hepática/virología , Factores de Tiempo , Resultado del Tratamiento , Carga Viral
6.
J Immunol Methods ; 313(1-2): 38-47, 2006 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-16753174

RESUMEN

The hepatitis B virus surface protein (HBsAg) displays the major B cells antigenic determinants that can induce protective immunity and prevent the hepatitis B virus (HBV) infection, a major health problem. A panel of murine monoclonal antibodies against the HBsAg (MAb anti-HBs), raised after mice immunization with a pool of plasma of hepatitis chronic carriers, has been established. Mainly using simple immunological tools such as enzyme-linked immunosorbent assay (ELISA) and Western blot analysis, we could trace the location of the epitopes on the HBsAg determinants. We also report the use of two specific methodology approaches based on molecular biology and biochemical techniques such as, respectively, cloning and expression of preS1 major neutralizing epitope of the HBsAg in Escherichia coli and ELISA accomplished to chemical reduction with dithiothreitol (DTT), which were able to complete the MAb anti-HBs characterization. Our results showed that the majority of the MAbs anti-HBs were directed to the HBV common determinant a. One MAb recognizes a discontinuous epitope present in all forms of the HBsAg when evaluated by Western blot.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Epítopos/inmunología , Antígenos de Superficie de la Hepatitis B/inmunología , Alquilación , Animales , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/aislamiento & purificación , Far-Western Blotting , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Glicoproteínas/inmunología , Antígenos de Superficie de la Hepatitis B/genética , Inmunoglobulina G/inmunología , Ratones , Ratones Endogámicos BALB C , Oxidación-Reducción , Precursores de Proteínas/genética , Precursores de Proteínas/inmunología , Proteínas Recombinantes de Fusión/inmunología , Proteínas del Envoltorio Viral/inmunología
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