Sera from two blood donors, one of whom was implicated in a case of post-transfusion hepatitis B, were found to be positive for anti-HBc and negative for HBsAg by conventional radioimmunoassay and were retested for HBsAg after concentration (pepsin digestion and polyethylene glycol precipitation). The presence of occult HBsAg was confirmed in both. These observations have implications for blood...

Sera from two blood donors, one of whom was implicated in a case of post-transfusion hepatitis B, were found to be positive for anti-HBc and negative for HBsAg by conventional radioimmunoassay and were retested for HBsAg after concentration (pepsin digestion and polyethylene glycol precipitation). The presence of occult HBsAg was confirmed in both. These observations have implications for blood...

Hepatitis B core antigen (HBcAg) was prepared from human liver tissue and used in an immunoelectro-osmophoresis screening test to detect antibody to HBcAg (anti-HBc) in patients with evidence of liver disease and in blood donors. With the exception of two immunosuppressed HBsAg carriers, anti-HBc was found in all cases of hepatitis B infection even when HBsAg was detectable only by radioimmunoa...

To evaluate the possibility of occult hepatitis B virus (HBV) infection in alcoholics carriers of "anti-HBc alone", and to verify the behavior of this serological pattern after a single dose of hepatitis B vaccine, 18 alcoholics who had this serological profile were evaluated by the polymerase chain reaction method, and 17 of them were vaccined. All were negative for HBV DNA. Nine (52.9%) of th...

BACKGROUND Home based care (HBC) has been an important component of the response to the AIDS epidemic in Africa, and particularly so before antiretroviral therapy (ART) became available. Has HBC become unnecessary now that ART is available in many African countries? One way to investigate this is to assess the changing need for comprehensive HBC as an ART programme becomes available. The Bangwe...

Conflicts between humans and Asiatic black bears ( Ursus thibetanus ) are widespread in Asia pose challenges to human-bear coexistence. Identifying effective mitigation measures requires a thorough understanding of conflicts (HBC). We assessed spatial-temporal patterns HBC their impact factors around the Baoshan Section Gaoligongshan Nature Reserve (GNNR) 2012 2020. The results suggested that c...

The recent addition of testing volunteer blood donors for antibody to hepatitis B core antigen (anti-HBc) has raised questions not apparent when such testing is applied to hepatitis B (HB) infected patients. The review of published studies, and our own, demonstrates that it is difficult to evaluate false positive results. Some patients appear to lose antibody to hepatitis B surface antigen (ant...

São Paulo, December 2, 2003 Dear Editor, In the original article “The biological meaning of anti-HBc positive result in blood donors: relation to HBV-DNA and to other serological markers” published in May-June 2003, the authors stated that “a recent study shows a high prevalence of anti-HBc (16%) in blood donors” and referred our paper (ALMEIDA NETO et al., 2001). Actually, we have not studied ...

Hepatitis B core antigen (HBcAg) was prepared from human liver tissue and used in an immunoelectro-osmophoresis screening test to detect antibody to HBcAg (anti-HBc) in patients with evidence of liver disease and in blood donors. With the exception of two immunosuppressed HBsAg carriers, anti-HBc was found in all cases of hepatitis B infection even when HBsAg was detectable only by radioimmunoa...

We investigate the molecular structure and vibrational properties of perchlorinated hexa-peri-hexabenzocoronene (HBC-Cl) by density functional theory (DFT) calculations and IR and Raman spectroscopy, in comparison to the parent HBC. The theoretical and experimental IR and Raman spectra demonstrated very good agreement, elucidating a number of vibrational modes corresponding to the observed peak...