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)

Among the known causes for the occurrence of hepatocellular carcinoma (HCC), chemical carcinogens, chronic alcoholic intake and hepatitis B virus (HBV), especially in Asia, has been emphasized. HBV has been industriously studied and many queries about the relationship between HBV infection and hepatocarcinogenesis have been clarified. Recent discovery of hepatitis C virus (HCV) revealed that there may be the participation of this virus in hepatocarcinogenesis. However, a precise mechanism in such a viral infection has not been known. Host immunological defence mechanisms including the role of cytokines should be also taken into consideration. Cellular gene abnormalities have been noted in the late period of cancer cell progression. The technical development in the clinically available diagnostic procedures have enabled us to detect early phase of HCC. Some new concepts in the pathological diagnosis of precancerous lesions of HCC and also early HCC have been reported recently. We gave an outline of the recent advances and references in the study of HCC.
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PMID:Recent advances in the study of hepatocellular carcinoma. 133 81

Hepatitis B virus infection is endemic in West Africa, and as a result, this region has a high rate of hepatoma. The recent development of an effective, safe vaccine against hepatitis B virus that provides durable immunity may now make feasible the prevention of persistent hepatitis B virus infection and thus the prevention of hepatoma. A comprehensive primary health care program in which over 70% of children in The Gambia, West Africa, receive all their childhood immunizations afforded a unique opportunity to carry out a large public health research program to prevent hepatoma and at the same time strengthen the country's primary health care program. In 1986, phased introduction of hepatitis B virus vaccine was initiated in The Gambia's Expanded Programme on Immunization. By 1990, 124,577 children had been carefully identified and recruited into the 35-year longitudinal cohort study; 59,803 of these children received hepatitis B virus vaccine. The other 62,774 unvaccinated children will serve as controls. Preliminary studies have demonstrated that the rate of hepatitis B virus infection has fallen to less than 5% in children who received all four doses of hepatitis B virus vaccine. This study should provide the data from which the protective efficacy of hepatitis B virus vaccine against hepatoma can be accurately determined. In addition, it has energized The Gambia's Expanded Programme on Immunization so that at present more than 90% of all children are receiving all their childhood immunizations. This model cancer prevention program demonstrates the potential synergy between public health research and practice.
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PMID:Hepatitis B virus vaccine in The Gambia, West Africa: synergy between public health research and practice. 133 28

The data generated by Yeh et al. on hepatitis B virus, aflatoxin, and primary hepatocellular carcinoma (PHC) in Southern Guangxi, China was used to evaluate the cancer potency of aflatoxin. We examined model fits to these data to explore whether hepatitis B virus (HBV) and aflatoxin intake act together to affect PHC rates in an additive, multiplicative, or interactive fashion, using relative and excess risk model forms. Purely additive models fit the data poorly. Fitted models were checked for plausibility by comparing predictions for the U.S. population with actual PHC incidence rates in the United States, and parameter stability was evaluated. The multiplicative relative risk and the interactive excess risk models provided satisfactory descriptions of the Yeh et al. data and U.S. PHC rates. There is about an eight-fold difference in the potency estimate for aflatoxin under the multiplicative relative risk (5.7 (mg/kg-day)-1) and interactive excess risk models (45.6 mg/kg-day)-1). The assumptions and limitations of the various models are discussed.
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PMID:Risk assessment for aflatoxin B1: a modeling approach. 133 6

Reports of an increase in a serum epoxide hydrolase (sEH), immunochemically related to microsomal EH in humans and rats with hepatocellular carcinoma (HCC), suggested its use as a serum marker for this disease. We have now measured sEH levels (as either immunochemically determined content or enzyme activity) in a number of human and experimental models of liver disease. sEH was elevated above the normal range in at least 50% of individuals with HCC, including: 3 of 6 northern Californians; 4 of 7 Koreans with hepatitis B-associated HCC; hepatitis B-associated HCC in woodchucks; and male rats receiving chronic treatment with aflatoxin B1 or ciprofibrate. sEH was rarely elevated in other forms of chronic liver disease. Only 2 of 9 Koreans with hepatitis B-associated cirrhosis, 1 of 8 carriers, but none with chronic active hepatitis or infection with no apparent liver disease had elevated sEH. In addition, no elevations were found in woodchucks with noncancerous viral hepatitis. In aflatoxin B1- and M1-treated rats sEH was not elevated in those with only hyperplastic foci or hepatocellular adenomas, and in two rat initiation-promotion protocols sEH was elevated only in those rats which received the entire set of treatments. sEH was also increased during acute hepatotoxicity in rats treated with CCl4 or 1,2-dibromo-3-chloropropane. The mechanism of increase in sEH during hepatocarcinogenesis appears to be different from that of other markers of HCC, for in the Korean patients, there was no correlation between sEH concentrations and those of alpha-fetoprotein or ferritin, nor was there a correlation with alpha-fetoprotein concentrations in the aflatoxin-treated rats. Furthermore, the increase in sEH does not correlate with induction of microsomal EH in the liver of experimental animals. Studies to date indicate that sEH is selective for HCC and severe hepatonecrotic injury, and may be of some use in the diagnosis of HCC, particularly as a complement to other serum markers.
Cancer Epidemiol Biomarkers Prev
PMID:Serum epoxide hydrolase (preneoplastic antigen) in human and experimental liver injury. 133 49

Hepatocellular carcinoma is one of the major human cancers, causing at least 250,000 deaths each year. Two of the major risk factors for this disease are aflatoxin exposure and hepatitis B virus. This study was undertaken to explore the relationship between dietary exposure to aflatoxins and the excretion of the major aflatoxin-DNA adduct and other metabolites into the urine of chronically exposed people who were either hepatitis B virus surface antigen-positive or -negative. The diets of 20 individuals, 10 males and 10 females, with ages ranging from 15 to 56 years, were monitored for 1 week, and aflatoxin intake levels were determined for each day. Starting on the fourth day, total 24-h urines were consecutively obtained for 4 days. The subjects were generally paired for hepatitis B virus status. Preparative monoclonal antibody affinity chromatography/high-performance liquid chromatography and competitive enzyme-linked immunosorbent assays were carried out on each of the urine samples, and the relationship between aflatoxin intake values and the excretion of (a) total aflatoxin metabolites and (b) aflatoxin-N7-guanine (AFB-N7-guanine) was determined. The average intake of total aflatoxins was 12.0 micrograms for the entire study group during the 1-week collection period. However, there was considerable day-to-day variation in exposures, from a low of zero to a high of 29.6 micrograms total aflatoxins/day. Initial efforts to characterize total aflatoxin metabolites in the urine samples were made by competitive enzyme-linked immunosorbent assay. The correlation coefficient for the analysis was 0.65, with P < 0.001.(ABSTRACT TRUNCATED AT 250 WORDS)
Cancer Epidemiol Biomarkers Prev
PMID:Molecular dosimetry of aflatoxin-N7-guanine in human urine obtained in The Gambia, West Africa. 133 82

The viral infections with greatest impact on the renal transplant recipient are those due to cytomegalovirus, Epstein-Barr virus, and the two hepatitis viruses, hepatitis B and C. All of these are modulated by the administered immunosuppressive therapy, and all have both direct and indirect effects on the transplant patient. The direct effects are the infectious disease clinical syndromes that are produced (fever and malaise, pneumonia, hepatitis, and so forth). The indirect effects are several--all of these viruses contribute to the patient's net state of immunosuppression, predisposing him or her to the development of opportunistic superinfection with a variety of pathogens. In addition, both Epstein-Barr virus and hepatitis B virus have been clearly linked to the development of certain malignancies (lymphoproliferative disease and hepatocellular carcinoma, respectively). Finally, cytomegalovirus has been linked to allograft injury. Although antiviral strategies effective for cytomegalovirus and Epstein-Barr virus infection are being developed, similar programs are not yet available for the hepatitis viruses.
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PMID:Viral infection in the renal transplant recipient. 134 23

Aflatoxins have long been suspected to be human hepatic carcinogens but no direct study was feasible until assays to measure individual aflatoxin exposure became available. We have used assays for urinary aflatoxin B1, its metabolites AFP1 and AFM1, and DNA-adducts (AFB1-N7-Gua) to assess the relation between aflatoxin exposure and liver cancer, as part of an ongoing prospective study of 18,244 middle-aged men in Shanghai, People's Republic of China. After 35,299 person-years of follow-up, 22 cases of liver cancer had been identified. For each case, 5 or 10 controls were randomly selected from cohort members without liver cancer on the date the disorder was diagnosed in the case and matched to within 1 year for age, within 1 month for sample collection, and for neighbourhood of residence. Subjects with liver cancer were more likely than were controls to have detectable concentrations of any of the aflatoxin metabolites (relative risk 2.4, 95% confidence interval 1.0-5.9). The highest relative risk was for aflatoxin P1 (6.2, 1.8-21.5). In an analysis adjusting for the effects of hepatitis B surface antigen seropositivity, level of education, cigarette smoking, and alcohol consumption, the relative risk for the presence of aflatoxin metabolites was 3.8 (1.2-12.2). There was a strong interaction between serological markers of chronic hepatitis B infection and aflatoxin exposure in liver-cancer risk. Reduction of aflatoxin exposure may be a useful intermediate goal in prevention of liver cancer, since the benefits of wide-scale hepatitis B vaccination will not be apparent for many years.
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PMID:Urinary aflatoxin biomarkers and risk of hepatocellular carcinoma. 135 Aug 20

Altered glycosylation of alpha-fetoprotein (AFP) has been proposed as a marker of hepatocellular carcinoma (HCC) in humans. The lectin-binding properties of woodchuck AFP were investigated to determine if woodchuck hepatitis virus (WHV)-induced HCCs are also accompanied by changes in AFP glycosylation. Ninety-eight to 100% of the AFP from normal, WHV-free woodchucks with physiologic AFP elevations and from WHV-carrier woodchucks with HCC bound to concanavalin A, indicating that virtually all of the AFP was glycosylated. Three percent or less of the serum AFP of normal woodchucks bound to Lens culinaris agglutinin (LCA). In contrast, the AFP from woodchucks with HCC had an increased LCA-binding fraction (range, 8-77%). The increased LCA-binding AFP in WHV-induced HCC is analogous to that which frequently accompanies hepatitis B virus (HBV)-induced HCC in humans. This study corroborates the relationship of altered glycoconjugate synthesis to virus-induced malignant transformation, confirms the importance of AFP glycoforms as markers of HCC, and demonstrates that the WHV-infected woodchuck should be useful in investigating changes in AFP glycosylation during hepadnavirus hepatocarcinogenesis and HCC growth.
Cancer Lett 1992 Apr 15
PMID:Altered glycosylation of alpha-fetoprotein in hepadnavirus-induced hepatocellular carcinoma of the woodchuck. 137 41

Chemotherapy is the mainstay of therapy for patients with non-Hodgkin lymphoma. Among side-effects associated with the use of chemotherapy, immunosuppression is one which can be potentially fatal. In hepatitis B carriers, immunosuppression permits widespread infection of the hepatocytes and its subsequent withdrawal causes an "immunological rebound" leading to massive necrosis of hepatocytes. 4 patients who died of fulminant hepatitis following chemotherapy are reported. These were patients with positive hepatitis B serology. Caution is advised when treating non-Hodgkin lymphoma in patients from hepatitis B endemic regions.
Eur J Cancer 1992
PMID:Fulminant hepatic failure in non-Hodgkin lymphoma patients treated with chemotherapy. 138 Dec 11

We analyzed the pattern of alpha-fetoprotein (AFP) synthesis in 40 consecutive human hepatocarcinomas (HCC) in relation to hepatitis B viral (HBV) infection. In addition, histopathological characteristics of liver parenchyma and the tumor itself were examined. Elevated AFP (> 20 ng/ml) were found in 90% of HCC patients and in none of the controls. In 35% of HCC cases, serum AFP was above 100,000 ng/ml. AFP levels were significantly higher in patients seropositive for hepatitis B surface antigen (HBsAg) compared with their negative counterparts (mean log[AFP]: 4.28 +/- 1.67 vs. 3.28 +/- 1.96, respectively; geometric mean (GM): 19,322.6 ng/ml and 1939.5 ng/ml, respectively; p < 0.05). Furthermore, serum AFP levels were higher in HCC patients with liver cirrhosis than in those without (log[AFP]: 4.43 +/- 1.58 vs. 3.23 +/- 1.98, respectively; p < 0.05). However, the relationship of cirrhosis with AFP was confounded by the high prevalence of HBsAg in cirrhotic HCC patients. There was no correlation of AFP with either liver necrosis (abnormal AFP in 45% of cases; mean log[AFP]: 3.99 +/- 1.91 vs. 3.75 +/- 1.85 for HCC with and without necrosis, respectively; 0.05 < p < 0.68, not significant (NS)), or inflammation (abnormal AFP in 25%; mean log[AFP]: 4.33 +/- 1.62 vs. 3.70 +/- 1.93 for HCC with and without inflammation, respectively; 0.05 < p < 0.39, NS). A vast majority of HCC (75%) were moderately (grade 2-3) or poorly differentiated tumors (grade 3, grade 4, or combined grade 3-4). Serum AFP did not correlate with tumor grade. Immunohistochemical analysis of HBsAg and AFP confirmed the serological findings, and confirmed earlier observations of elevated AFP in HBsAg-positive patients. These results may reflect pathogenic and biological differences between HBsAG-secreting and nonsecreting HCC.
Cancer Invest 1992
PMID:Alpha-fetoprotein synthesis in human hepatocellular carcinoma: correlation with hepatitis B surface antigen expression. 138 40


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