Hepatitis B e antigen-positive human serum was treated with 50-90% ethanol at room temperature for 1-60 min, then the antigenicity of S antigen (hepatitis B surface antigen, in a narrow sense) was determined by radioimmunoassay and the antigenicities of pre-S1 and pre-S2 antigens were measured by enzyme immunoassay. In addition, hepatitis B virus (HBV) DNA in the treated serum was detected by p...

UNLABELLED BACKGROUND AND RATIONALE FOR THE STUDY: Hepatitis B (HB) is one of the most prevalent occupational infections in health attendance environments. According to the Brazil Ministry of Health, health professionals must be vaccinated against the hepatitis B virus (HBV) and provide laboratory proof of immunization. AIMS To evaluate the seroprevalence of HBV infection and to analyze the r...

Breast fed infants may be at greater risk of mother to infant hepatitis B virus infection compared with formula fed infants. We studied 85 infants born to 84 hepatitis B surface antigen positive mothers (only two of whom were hepatitis B e positive), and who had received immunisation against hepatitis B virus. Our results indicate that breast feeding does not increase the risk of developing hep...

BACKGROUND Healthcare workers' practices regarding hepatitis B have an important effect on the control of this problem in workplaces. METHODS A questionnaire-based cross-sectional study was used to investigate the role of knowledge, cues to action, and risk perceptions as predictors of preventive behavioral intentions for hepatitis B among healthcare works in Broujen, Iran (n = 150). History ...

Hepatitis B surface antigen prevalence in populations of blood donors in Cameroon is estimated at 6% 16%. As such, the Objective of this study was to determine the prevalence of Hepatitis B surface antigen in a population of bank employees, who represent a sample closer to the general population. In tests carried out both Yaounde and Douala in December 2011, we detected the hepatitis B surface ...

OBJECTIVE To determine the immunogenicity of hepatitis B vaccine in preterm infants when the first dose of vaccine is delayed until hospital discharge. METHODS One hundred two preterm infants (23 to 36 weeks gestational age) born to hepatitis B surface antigen-negative mothers were enrolled. Immunization was initiated just before hospital discharge with subsequent doses 1 and 6 months later. ...

A pentadecapeptide (2F10 peptide) is capable of mimicking the group-specific "a" determinant of human hepatitis B surface antigen (HBsAg) at both the B- and the T-cell level. This peptide represents a sequence on the heavy-chain hypervariable region of a monoclonal "internal image" anti-idiotype (anti-id 2F10) that has partial sequence homology to the "a" determinant epitope of HBsAg. To identi...

This work shows that class II-linked humoral lack of response to an antigen can be overcome by joint immunization with the antigen and a T-helper cell determinant (TDh) well recognized by class II molecules of a non-responder individual. Thus, SJL/J mice (H-2s), which are non-responders to the S region of hepatitis B virus surface antigen (HBsAg), were rendered responders by joint immunization ...

The ability of potato-derived major surface antigen of hepatitis B virus (P-HBsAg) to elicit antibody responses to different dosages of P-HBsAg ranging from 0.02 to 30 μg administered orally in mice was examined. All immunized groups produced specific serum IgG and fecal IgA antibodies against P-HBsAg, even at low levels (<5 μg), after administration of a 0.5-μg yeast-derived HBsAg (Y-HBsAg; LG...