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G Taliani

Publications and source records attributed to G Taliani.

At least 55 records · Page 3Linked to original sources

Levels of pre-S antigens and HBV DNA in sera from high and low viremic HBV carriers.

The biological and clinical significances of pre-S antigens and HBV replication were investigated. Some 125 sera, 28 from HBeAg and 97 from anti-HBe-positive HBsAg, carriers were studied. The aim was to verify whether pre-S antigens could be expressed in serum in complete absence of viremia. Pre-S proteins, determined by an enzyme immunoassay, were found in sera regardless of the presence of HBV DNA, as detected by spot-hybridization. The sera without detectable HBV DNA were investigated further by PCR using specific primers for the S and C regions of HBV. PCR analysis of samples revealed that 4 out of 5 HBeAg and 33 out of 41 (80.5%) anti-HBe positive sera contained HBV-amplified sequences of S and C regions. Pre-S antigen values correlated well with the amounts of HBV DNA in serum detected by PCR in anti-HBe-positive subjects with high titers of pre-S antigens (10(4)-10(6)). In addition, PCR highlighted the presence of HBV DNA sequences in 8 out of 17 (47.1%) pre-S-negative HBsAg-positive sera.

Antibodies, Monoclonal↗

Correlation of preS antigens and clinical status during chronic hepatitis B virus infection.

The serum kinetics of preS1 and preS2 antigens has been evaluated in 38 serial samples from eight patients with chronic active (CAH) or chronic persistent (CPH) hepatitis, followed for 2-7 years (mean 4.4 years) in whom liver biopsy was performed at intervals, and in 46 samples from ten asymptomatic HBsAg carriers followed for 4-5 years (mean 4.6 years). Four patterns of preS behaviour have been observed: (1) persistently positive preS1 and preS2; (2) disappearance of preS2; (3) disappearance of both preS1 and preS2; and (4) persistently negative preS1 and preS2. Pattern 4 has been observed exclusively among healthy carriers, while seven out of eight chronic patients exhibited either pattern 1 or 2. Among the chronic patients, preS2 disappearance was accompanied or followed by alanine aminotransferase (ALT) normalization. The correlation of preS antigens with conventional viral replication markers showed that 100% of hepatitis B virus (HBV)-DNA-positive and 86.6% of HBeAg-positive sera were preS1/preS2 positive, while 61% of HBV-DNA-negative and 64% of HBeAg-negative sera were preS1/preS2 negative. Our data suggest that continuous monitoring of preS antigens in follow-up sera will allow for an improved prognostic evaluation of chronic HBV infection.

Adolescent↗

Clearance of hepatitis B virus DNA and pre-S surface antigens in patients with markers of acute viral replication.

To clarify the relationship between the pre-S antigens and other serological markers of hepatitis B virus (HBV) replication, we followed up 27 patients: 21 presented with symptoms of acute hepatitis (two progressed to chronicity) and six suffered from chronic hepatitis. Pre-S1, pre-S2, HBV DNA, IgM antihepatitis core antigen (HBc), hepatitis B e antigen (HBeAg), and anti-HBe were detected in about 200 sera serially collected at different times for at least 6-12 months from the onset of clinical observation. In the early symptomatic phase of acute hepatitis, the pre-S1 and pre-S2 antigens were present in 95% of the cases and correlated well with high levels of alanine-transferase (ALT) and IgM anti-HBc, while HBV DNA was present in the sera of only six (28.6%) patients (P less than 0.0001). This was the first marker to disappear (1 month after the initial stage). All of the HBV DNA-positive patients were also HBeAg positive, whereas no HBeAg-negative subjects were found with serum HBV DNA. In the six chronic patients, pre-S antigens were always present independently of the HBeAg/anti-HBe status; HBV DNA was detected in three of them, even if transiently, and in two of these it reappeared together with pre-S2 epitope. The follow-up data suggest that, in acute hepatitis, the clearance of pre-S antigens can be considered as a prognostic index of clinical resolution and that, in chronic hepatitis, the persistence of pre-S antigens seems to indicate progression of the disease. In particular, pre-S2, in patients in whom it is intermittent, can be considered as an index of reactivation.

Acute Disease↗

Incidence of hepatitis B virus DNA and DNA-polymerase in sera of Italian asymptomatic carriers with the serological markers of HBV.

The presence of Hepatitis B virus (HBV) DNA in sera of patients with HBV related diseases is considered a reliable marker of virus active replication. In this paper HBV DNA was assayed by the molecular hybridization method with a 32P labeled nick translated HBV probe. The assay was positive in sera of 21 out of 22 HBeAg-positive and 4 out of 8 HBeAg-negative asymptomatic HBsAg carriers. 15 HBsAg-negative sera obtained from healthy donors showed no HBV DNA. Almost 80 per cent of HBeAg and HBV DNA positive sera revealed a DNA-polymerase activity. In order to determine the infectivity of HBsAg carriers, it appears that, whenever possible, the HBV DNA spot hybridization should be performed in conjunction with the DNA-polymerase, HBsAg and HBeAg tests.

Carrier State↗

Seroepidemiology of infection with hepatitis A virus and hepatitis B virus in the Seychelles.

A batch of 417 serum samples obtained from native-born subjects were tested for the presence of hepatitis B surface antigen (HBsAg) and corresponding antibody (anti-HBs), by enzyme-linked immunosorbent assay (ELISA); and antibodies to hepatitis B core antigen (anti-HBc), e-antigen (anti-HBe), and hepatitis A virus (anti-HAV), by radioimmunoassay (RIA). HBsAg was found in only two of the 417 subjects studied. Anti-HBs was detected in 112 samples (26.8%), anti-HBc in 114 (27.3%) and anti-HBe in 31 samples (7.4%). Serologic evidence of a previous or present infection by hepatitis B virus (HBV) was found in 34.5% of the samples studied. Males showed a greater prevalence of anti-HBs and anti-HBc, while anti-HBe was more common in females; however, these differences were not significant. With regard to age, a significantly higher prevalence of anti-HBs (p less than 0.05), anti-HBc (p less than 0.025) and anti-HBe (p less than 0.025) was found in the older age groups. Anti-HAV antibodies were present in 90% of the subjects studied, with no variation between the sexes. The anti-HAV rate in the group under 20 years was similar to that found in the older age groups. The total infection rate of hepatitis B virus in the Seychelles is lower than in other tropical areas, HBs antigen/antibody ratio approaching that in temperate areas. Elucidation of the reasons for the low prevalence of hepatitis B virus carriers among the Sevchelles population requires further investigation.

Adolescent↗

[Advantages of spectrophotometric reading of ELISA plates for determination of the HBs/anti-HB system].

It has been tested some diluted HBsAg and anti-HBs positive sera by modified ELISA test. We have found a correlation between HBsAg titer and spectrophotometric reading value and we have shown it in a curve. On the other hand, by neutralization of different dilutions of a RIA anti-HBs positive serum with different dilutions of a HBsAg positive serum we have carried out a checkboard and we have found that the best titer for neutralizing HBsAg is 30 ng/ml. This HBsAg has been called "standard". Using HBsAg "standard" we have tested 50 sera of hemophiliacs and we have found 1 HBsAg positive (2%) and 38 anti-HBs positive patients (76%).

Antibodies, Viral↗