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Biomedical subjects

H Yotsuyanagi

Publications and source records attributed to H Yotsuyanagi.

At least 19 recordsLinked to original sources

Successful treatment of hepatitis B virus-associated membranous nephropathy with lamivudine.

We present a case of chronic hepatitis B with membranous nephropathy, that was improved by lamivudine treatment. A 37-year-old man was admitted to our hospital for the evaluation of proteinuria. He was diagnosed as having chronic glomerulonephritis associated with chronic hepatitis B. Histopathological findings of the renal biopsy specimen indicated membranous nephropathy. He suffered from nephrotic syndrome associated with leg edema, which was parallel to the exacerbation of hepatitis. Lamivudine was started for the treatment of hepatitis, which caused the disappearance of serum hepatitis B virus DNA and the normalization of ALT level in 4 weeks. Additionally, proteinuria disappeared 120 weeks after the treatment was started. Lamivudine treatment may remit HBV-associated nephropathy.

Adult↗

Frequent presence of HBV in the sera of HBsAg-negative, anti-HBc-positive blood donors.

BACKGROUND: Recent studies have revealed that HBV may not be cleared even after the disappearance of serum HBsAg. The purpose of this study was to investigate whether the replication of HBV persists in HBsAg-negative blood donors who lack apparent liver disease. STUDY DESIGN AND METHODS: Serum HBV was examined by using PCR coupled with Southern blotting in 50 blood donors who were identified to be HBsAg negative but anti-HBc positive. RESULTS: HBV DNA was detected in the sera from 19 (38%) of 50 donors. In 11 of the 19, HBV existed exclusively as immune complexes, while HBV presumably did not exist as immune complexes in the remaining eight. The levels of HBV DNA were similar to those in patients who had recovered from acute HBV. Some nucleotide substitutions, which did not confer amino acid changes in the major epitope of HBsAg, were found in the preS-S regions. CONCLUSION: The replication of HBV is ongoing in a substantial proportion of healthy blood donors who have anti-HBc. Blood from such donors may contain very low levels of HBV free of immune complex formation and should be excluded for transfusion. The fact that such blood donors apparently lacked liver disease suggests no pathogenicity of such "occult" HBV.

Adult↗

A case-control study for clinical and molecular biological differences between hepatitis B viruses of genotypes B and C. Japan HBV Genotype Research Group.

Clinical and molecular virological differences were evaluated in 50 Japanese patients chronically infected with HBV of genotype B and C who were matched for age and sex as well as the severity of liver disease in a case-control study. Hepatitis B e antigen (HBeAg) was significantly less frequent (16% vs. 42%, P <.01), whereas antibody to HBeAg (anti-HBe) was significantly more common (84% vs. 56%, P <. 01) in genotype B than C patients. The predominance of mutants with G-to-A mutation at nucleotide (nt) 1896 in the precore region (A1896) over the wild-type was comparable between genotype B and C patients (60% and 62%, respectively), and it correlated with anti-HBe. The double mutation in the basic core promoter (A-to-T at nt 1762 and G-to-A at nt 1764), however, was significantly more frequent in genotype C than B patients (58% vs. 16%, P <.01), and it did not correlate with anti-HBe or HBeAg. By the multiple logistic regression analysis, the double mutation in the basic core promoter (T1762/A1764) was significantly associated with genotype C [odds ratio (OR), 9.3; 95% confidence interval (CI), 3.4-25.1]], age > or = 35 years (OR, 5.5; CI, 1.5-20.5), and more advanced liver disease (OR, 4.1; CI, 1.6-10.2), but it was not associated with sex, HBeAg, HBV DNA, or the precore mutation (A1896). These results suggest a role of the double mutation in the basic core promoter in association with genotype C and a longer duration of infection in the aggravation of chronic hepatitis B.

Adult↗

The significance of hepatitis B virus DNA detected in hepatocellular carcinoma of patients with hepatitis C.

BACKGROUND: Recently, it has been reported that hepatitis B virus (HBV) DNA is detected in cancerous liver tissues in some hepatitis B surface antigen negative chronic hepatitis C patients with hepatocellular carcinoma (HCC). However, the significance of HBV DNA detected in such cases remains unclear. METHODS: The authors determined the presence or absence and the titers of HBV DNA in the liver tissue of anti-hepatitis C virus (HCV) positive/HBs antigen negative patients with HCC by polymerase chain reaction (PCR) and Southern hybridization, and correlated them with clinicopathologic parameters. RESULTS: HBV DNA was found in cancerous liver tissues from 12 (50.0%) of the 24 patients studied. However, Southern hybridization of genomic DNA in the cancerous liver tissues led to detection of HBV DNA in only 3 (12.5%) of the 24 patients, suggesting that the copy number of HBV DNA may be very low in most cases. Indeed, the titration of HBV DNA in cancerous liver tissues performed by the end point dilution method revealed that most contained less than one copy of HBV DNA per cell, although cells of monoclonal origin carrying integrated HBV DNA should have at least one copy of it. There was no significant difference in HBV DNA positivity between the HCC patients with and without underlying cirrhosis. CONCLUSIONS: The results of this study corroborate previous reports of frequent detection of HBV DNA in the liver tissue of anti-HCV positive/HBs antigen negative patients with HCC, but do not support an essential role of HBV in hepatocarcinogenesis in patients with chronic hepatitis C and occult HBV infection.

Aged↗

Virologic analysis of non-B, non-C hepatocellular carcinoma in Japan: frequent involvement of hepatitis B virus.

Serum and liver tissues from hepatitis B surface antigen-negative/anti-hepatitis C virus (HCV)-negative (non-B, non-C) hepatocellular carcinoma (HCC) patients in Japan were examined for the presence of hepatitis B virus (HBV), HCV, and TT virus (TTV) by polymerase chain reaction. The studies evaluated the contribution of these viruses to pathogenesis of HCC. HBV DNA was detected in the sera of 20 (47.6%) of 42 non-B, non-C HCC patients, which was significantly higher than in age-matched controls without liver disease (P<.001). In 8 of 12 patients with liver tissues available, HBV DNA was detected in cancerous and adjacent noncancerous liver tissues. No HCV RNA was detected. The positivity for TTV DNA was not significantly different between HCC patients and controls. These results indicate that HBV is associated with a substantial proportion of non-B, non-C HCC cases in Japan. The role of HBV in hepatocarcinogenesis in such patients needs to be clarified.

Adult↗

Hepatitis viral infection in Behçet's disease.

To elucidate the role of hepatitis viruses in the pathogenesis of Behçet's disease (BD), we measured hepatitis viral markers (anti-hepatitis A (anti-HA), HBsAg, anti-HBs, anti-HBc) and viral nucleic acids (hepatitis B virus (HBV)-DNA, hepatitis C virus (HCV)-RNA, GB virus C (GBV-C)-RNA, TT virus (TTV)-DNA) in the sera of 68 BD patients along with 76 blood donors matched for age and sex. Positivity of anti-HA in patients with BD (36.8%) was lower than that in blood donors (68.0%). Both anti-HCV and HCV-RNA were detected in only one (1.5%) patient with BD and in none of the blood donors. The prevalence ratios of HBsAg, anti-HBs, anti-HBc in both groups were similar (2.9:0, 16.2:15.8 and 17.7:19.7%, respectively). However, serum HBV-DNA was detected more frequently in BD patients (8/68; 11.8%) than in blood donors (2/76; 2.6%) (P<0.05). The prevalence of GBV-C-RNA was also higher in patients with BD (4/68; 5.9%) compared with blood donors (0%). However, characteristics and clinical features are similar between GBV-C-RNA-positive and -negative groups. With respect to the prevalence of TTV-DNA, there was no significant difference between BD patients (23.5%) and blood donors (30.3%). Our study indicates that HBV and GBV-C infection might be related to BD, although the role of these viruses remains to be investigated.

Journal Article↗

Steatosis and intrahepatic hepatitis C virus in chronic hepatitis.

Hepatic steatosis has been reported as one of the characteristics which discriminates hepatitis C from other forms of hepatitis, besides lymphoid follicles and bile duct damage. However, it is unclear whether or not the presence of hepatitis C virus (HCV) itself is associated with the development of steatosis. The possibility that the HCV itself is directly related to the development of steatosis was examined. The intrahepatic core protein levels, as a marker of the HCV load, were correlated with the presence of steatosis in 43 patients with chronic hepatitis C. Among 43 patients studied by Western blotting, the core protein was detected in the liver in 27 (62.8%). On the other hand, hepatic steatosis was observed in 21 (48.8%) of the 43 patients. Importantly, the core protein was detectable in 19 (90.4%) of the 21 patients with steatosis, while it was detected in only 8 (36.4%) of the 22 patients without steatosis (P = 0.008). However, serum HCV-RNA levels as determined by the Amplicor monitor were not significantly different between patients with and without steatosis. Multivariate analysis showed that the serum alanine aminotransferase level (P = 0. 013), body mass index (P = 0.038), and intrahepatic HCV core protein positivity (P = 0.038) were the independent parameters best predictive of steatosis. These results indicate a close relationship between intrahepatic HCV and the development of steatosis, and suggest a possible role of the HCV itself or core protein in the pathogenesis of steatosis in human chronic hepatitis C.

Aged↗

Compensatory apoptosis in preneoplastic liver of a transgenic mouse model for viral hepatocarcinogenesis.

The HBx protein of hepatitis B virus has been shown to induce hepatocellular carcinoma in transgenic mice as direct evidence for its involvement in hepatocarcinogenesis. In these transgenic mice, however, it is not clear why hepatocytes do not acquire a neoplastic phenotype by 13 months old despite the continuous growth stimulation by the HBx protein from 2 months old. In this study, we show that the accelerated proliferation of hepatocytes is counterbalanced by apoptosis, which maintains liver homeostasis. A decrease in the extent of apoptosis seems to precede the emergence of neoplasia in the transgenic mouse liver. The disappearance or block of apoptotic signals, which may be the result of additional genetic or epigenetic aberrations, may result in the preneoplastic hepatocytes becoming neoplastic.

Aging↗

Precore wild-type DNA and immune complexes persist in chronic hepatitis B after seroconversion: no association between genome conversion and seroconversion.

Precore hepatitis B virus (HBV) mutants may gradually prevail during or after seroconversion (SC) from hepatitis B e antigen (HBeAg) to hepatitis B e antigen antibody (anti-HBe) status in many chronic hepatitis B (CH-B) patients. However, patients with CH-B still produce anti-HBe more than several years after SC, and the relationship between SC and genome conversion in the precore region has not been clarified. Therefore, in patients with CH-B who had a sustained loss of HBeAg and complete remission of hepatitis after SC, the precore region was sequenced in paired serum samples from 1 year before SC to 3 years after SC. Mutant precore defective HBV DNA was found in only 6 (19%) of 31 CH-B patients who had a complete remission of hepatitis after SC. Mixed-type HBV DNA (precore wild-type and mutant-type) was found in 4 (13%) patients. Wild-type HBV DNA was found in 21 (68%) CH-B patients after SC. Longer-term follow-up of 11 CH-B patients indicated that 3 of 11 patients experienced precore genome conversion 2 to 3 years after SC. E-plus DNA or e-minus DNA was semiquantitated by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) assays before and after SC. E-plus DNA levels decreased from 10(5.56+/-1.58) to 10(2.45+/-1.61). Similarly, e-minus DNA levels declined from 10(4.25+/-1.56) to 10(1.86+/-1.37). By dot-blot assay, serum HBV DNA became negative soon after SC, as did serum HBeAg. In contrast, HBeAg-containing immune complexes were still detected after SC. Anti-HBe antibody was produced throughout SC and thereafter, as determined by a sensitive experimental assay. Therefore, we conclude that genome-conversion in the precore region is a separate event from HBeAg/anti-HBe seroconversion.

Acute Disease↗

Persistent viremia after recovery from self-limited acute hepatitis B.

To define the duration of viremia in the course of acute hepatitis B, we semiquantitatively determined the levels of hepatitis B virus (HBV) DNA in the sera, using polymerase chain reaction (PCR) coupled with Southern blotting, of non-immunocompromised patients with self-limited acute hepatitis B. In the sera of 10 of 11 patients, HBV DNA, which was presumably coated with viral proteins, was detected for a long period after recovery, even at the final observation times, which ranged from 6 to 19 months after disease onset. To characterize the mode of HBV that was present in serum, we immunoprecipitated immune complexes in sera by the addition of anti-human immunoglobulin G (IgG) and determined the levels of HBV DNA separately in the supernatants and pellets. In the acute phase of hepatitis B, high levels of HBV DNA were detected both in the supernatants and pellets at comparative levels. After the convalescent phase, the amount of HBV DNA in the supernatant decreased with respect to that in the pellets. It is notable that, in most cases, serum HBV persisted as a form of immune complex even after the seroconversion to antibody to hepatitis B surface antigen (anti-HBs). These data suggest that the replication of HBV may persist in some organs, most likely in the liver or peripheral blood cells, for a long period after recovery from acute hepatitis B, and the data indicate the possible transmission of HBV from organ transplantation donors who exhibit serological markers of past infection only.

Acute Disease↗

Regulation of Fas gene expression in HeLa cells as determined by modified RT-PCR.

We determined human Fas messenger RNA (mRNA) levels in HeLa cells using a 'mutagenic' reverse transcription-polymerase chain reaction, which quantitates mRNA levels using the corresponding genomic DNA as an internal control. The expression level of Fas mRNA was very low in serum-deprived quiescent HeLa cells. In conjunction with the start of cell-cycle progression upon the addition of serum to culture medium, the Fas mRNA level gradually increased, reached its peak at 36 h and returned to the basal level after 48 h. HeLa cells at 36 h exhibiting a high level of Fas mRNA expression were more susceptible to the anti-Fas antibody apoptotic signal. Thus, the regulation of Fas expression is associated with cell-cycle progression, and this method for Fas mRNA detection may be useful, particularly for the analysis of small amounts of samples.

Antibodies↗

The core protein of hepatitis C virus induces hepatocellular carcinoma in transgenic mice.

Hepatitis C virus (HCV) is the main cause of chronic hepatitis worldwide. Chronic hepatitis ultimately results in the development of hepatocellular carcinoma (HCC). However, the mechanism of hepatocarcinogenesis in chronic HCV infection is still unclear. The ability of the core protein of HCV to modulate gene transcription, cell proliferation and cell death may be involved in the pathogenesis of HCC. Here, we report the development of HCC in two independent lines of mice transgenic for the HCV core gene, which develop hepatic steatosis early in life as a histological feature characteristic of chronic hepatitis C. After the age of 16 months, mice of both lines developed hepatic tumors that first appeared as adenomas containing fat droplets in the cytoplasm. Then HCC, a more poorly-differentiated neoplasia, developed from within the adenomas, presenting in a 'nodule-in-nodule' manner without cytoplasmic fat droplets; this closely resembled the histopathological characteristics of the early stage of HCC in patients with chronic hepatitis C. These results indicate that the HCV core protein has a chief role in the development of HCC, and that these transgenic mice provide good animal models for determining the molecular events in hepatocarcinogenesis with HCV infection.

Animals↗

Acute exacerbation of autoimmune liver disease associated with hantaviral infection.

Hantavirus is known to cause haemorrhagic fever with renal syndrome (HFRS). Although liver dysfunction has been reported in HFRS, hepatic manifestations of hantaviral infection have not been well described. We describe a case of autoimmune cholangitis in which an exacerbation of hepatitis was associated with hantaviral infection. Seroconversion of both IgG- and IgM-class antibodies to hantavirus was noted coincident with acute exacerbation of hepatitis, which was resolved promptly by treatment with corticosteroid. No extrahepatic manifestations were noted. This case suggests that hantavirus may trigger acute exacerbation of autoimmune liver disease without extrahepatic manifestations and that it may cause community-acquired hepatitis.

Antibodies, Antinuclear↗

Sialadenitis histologically resembling Sjogren syndrome in mice transgenic for hepatitis C virus envelope genes.

Hepatitis C virus (HCV), a major causative agent of non-A, non-B chronic hepatitis, is also suggested to be associated with extrahepatic manifestations such as mixed cryoglobulinemia and glomerulonephritis. Two independent lines of transgenic mice carrying the HCV envelope genes have been shown previously to express the HCV envelope proteins in organs, including the liver and salivary glands, which results in no pathological changes in the liver. Further analysis of these animals now has revealed that they develop an exocrinopathy involving the salivary and lachrymal glands. This pathology resembles Sjogren syndrome, which also is suggested to have a possible association with chronic hepatitis C. These observations suggest that HCV might be involved in the pathogenesis of sialadenitis in humans and that this transgenic mouse system would be a good animal model for the study of HCV infection.

Age Factors↗