Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Discordant results for e antigen, DNA polymerase activity, and Dane particle frequency were noted in the sera of two patients representing an index case-contact case pair with chronic aggressive hepatitis B. The lack of correlation between presence of e antigen and the infecting viral strain, as well as the strong relationship of e antigen to persistent and significant viremia, emphasize the role of the host's immune response in the expression of this antigen.
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PMID:Discordant e antigen, DNA polymerase activity, and Dane particle responses in two patients representing an index case-contact case pair with hepatitis B virus infection. 40 11

Evidence available indicates that the so-called Dane particles are the hepatitis virus. A DNA polymerase is associated with the core of these particles. The probability that this is the viral DNA polymerase offers the possibility of preventing hepatitis B multiplication by selective inhibition of this enzyme. This investigation reports that trisodium phosphonoformate (PFA) at low concentrations but not phosphonoacetate acid (PAA) inhitits Dane particle associated DNA polymerase.
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PMID:Trisodium phosphonoformate inhibits hepatitis B Dane particle DNA polymerase. 43

To determine if the presence of hepatitis B e antigen (HBeAg) and elevated DNA polymerase activity in the serum of chronic HBeAg carriers indicate increased contagiousness in a household setting, the household contacts of 74 carriers were prospectively evaluated for serologic evidence of hepatitis B infection. Thirty of the HBsAg carriers had HBeAg and 44 had anti-HBe. Twenty-eight HBeAg-positive carriers regularly demonstrated elevated DNA polymerase when serially drawn serum samples were analyzed. None of the anti-HBE-positive carriers demonstrated elevation of DNA polymerase activity. Both household contacts of HBeAg-positive and anti-HBe-positive carriers demonstrated serologic evidence of hepatitis B infection (HBsAg, anti-HBs, and anti-HBc). However, infection was significantly more frequent among spouses and sexual partners of carriers who had either HBeAg (P less than 0.001) or elevated DNA polymerase activity (P less than 0.001). Thus, the data indicate that a particular subpopulation of spouses and sexual partners of hepatitis B carriers are at significantly greater risk for acquiring infection.
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PMID:Hepatitis B e antigen, DNA polymerase activity, and infection of household contacts with hepatitis B virus. 43 28

Serum levels of hepatitis B virus specific DNA polymerase and hepatitis B e antigen were studied serially in 34 patients with hepatitis B virus infection--20 who had the acute illness and recovered, seven who died with fulminant disease, three who died as a result of subacute hepatic necrosis, and four who went on to develop chronic active hepatitis. DNA polymerase activity was present in 16 (80%) and HBeAg in 13 (65%) of the uncomplicated cases at presentation and in all of those patients from whom the initial sample was obtained before the peak in aminotransferase. Both markers disappeared after 30 days from the onset but DNAP remained persistently positive during a follow-up period of four to 10 months in the four patients who progressed to chronic hepatitis. These results indicate that DNAP and HBeAg are transiently present in all cases of acute hepatitis B. Only their persistence after the acute episode could represent a useful prognostic marker of chronically. In this respect, DNAP was more reliable in our patients than HBeAg. In uncomplicated acute hepatitis, the peak in DNAP levels, which defines the time of maximum virus replication in the liver, preceded the peak in aminotransferase levels. Among the 10 patients who developed massive liver damage after hepatitis B infection, DNAP was detected in five of the seven with fluminant hepatitis, with enzyme levels that were comparable with those observed in uncomplicated acute hepatitis and presentation, but not in the cases of subacute hepatic necrosis. These findings are consistent with the hypothesis that in hepatitis B infection, liver damage, whatever the severity, is not directly related to the degree of virus replication.
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PMID:Changes in hepatitis B virus DNA polymerase in relation to the outcome of acute hepatitis type B. 43 51

A study was undertaken to assess the state of hepatitis B virus (HBV) infection in hemodialysis patients. From 97 hemodialysis patients tested, 51 were found to have at least one hepatitis B virus specific marker. 18 were HBsAg carriers, 12 of these carriers have to be regarded as infectious as judged from the presence of HBeAg and/or HBV-specific DNA polymerase activity in the serum. Antinuclear antibodies (ANA) were found in the sera of approximately 20% of the hemodialysis patients with a high prevalence in cases which lacked HBV markers. We conclude from our study that HBsAg-positive hemodialysis patients should be dialyzed in a separate unit and preferably served by personnel which is anti-HBs-positive. The question whether patients in which anti-HBc represents the only HBV marker should be separated is still open and needs further work. The role of non-A/non-B infection is difficult to determine and further studies are needed to elucidate this question.
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PMID:Hepatitis B virus markers in 97 long-term hemodialysis patients. 49 11

HBeAg/anti-HBe and Dane particle-associated DNA polymerase activity were detected in serum samples from 358 HBsAg asymptomatic carriers found during normal routine screening of 11,200 blood donors (HBsAg prevalence 3.1%). Since virus specific DNA polymerase activity and HBeAg seem to be associated in some way with hepatitis B virus infectivity and liver damage, 5% of the HBsAg carriers examined, as detected by the presence of HBeAg, and 9.5%, as shown by DNA polymerase activity, can be expected to have liver damage and a potential risk of transmitting hepatitis B to contacts. On the other hand, 48% of subjects were theoretically healthy and non-infective because of the presence of anti-HBe in their blood. The differentiation of groups of asymptomatic HBsAg carriers, on the basis of these serological markers, may have important clinical and epidemiological implications.
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PMID:Prevalence of HBeAg, anti-HBe and Dane particle-associated DNA polymerase activity in asymptomatic carriers of HBsAg. 49 12

Eight patients with chronic hepatitis B infection (seven with chronic active hepatitis and one with chronic persistent hepatitis) were treated with daily intramuscular injections of human leucocyte interferon for periods of 5 to 8 weeks and in one case for 5 months. In one patient there was a marked fall in virus-associated DNA polymerase activity and in the number of DNA containing viral particles during each of two courses of interferon. Hepatitis Be antigen (HBeAg) also disappeared, the aspartate transaminase levels fell and liver histology improved. In the four other patients with detectable DNA polymerase activity there was an early fall but this was transient and in one of these patients there was a continuing rise in activity despite treatment. One other patient became HBeAg negative but hepatitis B surface antigen (HBsAg) titres were mostly unaffected by treatment. A marked decrease in T-lymphocyte mediated cytotoxicity towards HBsAg coated target cells was demonstrated and raises the possibility that an immunosuppressant action of interferon may offsets its direct anti-viral action but may also account for the improvement in liver function which occurred in some patients.
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PMID:Effects of human leucocyte interferon on hepatitis B virus replication and immune responses in patients with chronic hepatitis B infection. 50 26

In order to evaluate the potential infectivity of blood of hepatitis B patients, the Dane particle associated DNA polymerase was determined, which is a reliable marker for the presence of complete viral particles. Enzyme activities were compared with hepatitis B e antigen (HBeAg) titers determined by radioimmunoassay. Detectable DNA polymerase activity was only present in HBeAg positive blood, preferentially in samples with high antigen titers (1 : 1000 and above). These samples therefore have to be considered as highly infectious. However, blood with low HBeAg levels and free of detectable polymerase activity can still be infectious, since the polymerase reaction is rather insensitive compared to the radioimmunological HBeAg determination.
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PMID:Quantitative correlation between the Dane particle-associated DNA polymerase and the hepatitis B e antigen. 51 39

A radioimmunoassay for hepatitis e antigen (HBeAg) and antibody to e (anti-HBe) was developed and sera of 71 asymptomatic chronic carriers of hepatitis B surface antigen (HBsAg), in 44 of whom liver biopsy was obtained, were tested. In addition, testing for Dane particle associated DNA polymerase activity was performed in all sera. HBeAg was detected in 14 subjects (19.7%) and anti-HBe in 46 (64.8%). The highest proportion of HBeAg positivity (40%) was found among carriers with histological evidence of chronic hepatitis, whereas anti-HBe was present in 80% of carriers with normal liver histology, in 58% of carriers with non-specific reactive hepatitis and in 60% of carriers with chronic liver lesions. DNA polymerase activity was present in 92.8% of sera positive for HBeAg, in 13% of sera positive for anti-HBe, and in 9% of sera negative for both markers. Our results demonstrate that not all HBsAg carriers reactive to HBeAg show evidence of chronic hepatitis nor, conversely, that anti-HBe is invariably associated with the healthy carrier state of HBsAg. Finally, circulating Dane particles, as revealed by the presence of serum specific DNA polymerase activity, may also be present in anti-HBe positive sera other than those of some HBsAg carriers lacking both HBeAg and anti-HBe.
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PMID:Radioimmunoassay in the detection of the hepatitis B e antigen/antibody system in asymptomatic carriers of hepatitis B surface antigen. Correlation with serum Dane particle associated DNA polymerase activity. 54 99

Family members of 34 asymptomatic HBsAg carriers were tested for different hepatitis B virus (HBV) markers. Among 67 family members tested 24 (36%) presented signs of a past or ongoing HBV-infection. Spread of HBV-infection was particularly high in those families in which the HBsAg carrier was positive for HBeAg and Dane particle-associated DNA polymerase activity. Non-parenteral "horizontal" transmission of HBV among spouses and brothers and sisters and probably parenteral vertical transmission of HBV from carrier mothers to their infants occurred in approximately the same frequency. Fathers transmitted HBV unfrequently to their offsprings. The results show that the risk to acquire a HBV-infection from an asymptomatic HBsAg carrier is closely linked to the serological findings in the HBe/anti-HBe-system of the index HBsAg carrier and not to the family relationship to the HBsAg carrier.
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PMID:[Spread of hepatitis B virus infection among family contacts of asymptomatic HBsAg carriers (author's transl)]. 54 1


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