[Divergence and heterogeneity of HDV-RNA sequences in Japan].
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Base Sequence↗
Biomedical subjects
Fumio Imazeki
Publications and source records attributed to Fumio Imazeki.
[HDV genomic change and pathogenesis].
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Amino Acid Sequence↗
Hepatocyte growth factor activator inhibitor 2/placental bikunin (HAI-2/PB) gene is frequently hypermethylated in human hepatocellular carcinoma.
To identify methylation-mediated silencing of genes in hepatocellular carcinoma (HCC), we surveyed genes induced by treatment with 5-aza-2'-deoxycytidine (5-Aza-CdR) in six human hepatoma cell lines using cDNA microarray analysis and determined the methylation status of 5' CpG islands by bisulfite DNA sequencing or methylation-specific PCR. Fifty genes exhibited a >5-fold induction in response to treatment with 5-Aza-CdR in at least one of the hepatoma cell lines examined. Among these genes, the hepatocyte growth factor activator inhibitor 2/placental bikunin (HAI-2/PB) gene was maximally induced by 5-Aza-CdR in three of six cell lines studied (HLE, HuH7, and Hep3B). Bisulfite sequencing revealed that the 5' CpG island of this gene was densely methylated in HLE, HuH7, and Hep3B cells. After treatment with 5-Aza-CdR, re-expression and demethylation of HAI-2/PB gene were detected in these cells. These findings suggest that HAI-2/PB expression may be inappropriately repressed by promoter hypermethylation in HCC. Methylation-specific PCR analysis demonstrated that HAI-2/PB hypermethylation occurred in 21 of 26 HCC tumors (80.8%), whereas in the corresponding nontumorous liver tissues, it was found in 7 of 26 samples (26.9%). In addition, HAI-2/PB hypermethylation was not detected in any of the seven normal liver samples from individuals without HCC. Reverse transcription-PCR analysis demonstrated that promoter hypermethylation was associated with the reduced expression of the HAI-2/PB gene in HCC tumors. In conclusion, we have found that the HAI-2/PB gene is silenced by promoter hypermethylation in human hepatoma cells by means of cDNA microarray analysis after 5-Aza-CdR treatment, and that HAI-2/PB hypermethylation occurs frequently in primary HCC tumors.
Antimetabolites, Antineoplastic↗
Gene expression profiling reveals the mechanism and pathophysiology of mouse liver regeneration.
Comprehensive analysis of the changes in gene expression during liver regeneration was carried out by using an in-house microarray composed of 2,304 distinct mouse liver cDNA clones. Mice were subjected to partial two-thirds hepatectomy, and changes in mRNA levels were monitored up to 48 h. Of the 2,304 genes analyzed, 496 genes showed expression levels measurable at all time points after the partial hepatectomy. 317 genes were up- or down-regulated 2-fold or more at least at one time point during liver regeneration and were classified into eight clusters based on their expression patterns. With a more stringent cut-off value of +/-2 S.D., 68 genes were listed and were classified into five clusters. In these two analyses with different clustering criteria, functionally categorized genes showed similar cluster distributions. Genes involved in protein synthesis and posttranslational processing were significantly enriched in the cluster characterized by rapid gene activation and subsequent persistence. This suggests the importance of modulating the efficiency of protein supply and/or altering the composition of protein population from the early phase of hepatocyte proliferation. Genes for two major liver functions, i.e. plasma protein secretion and intermediate metabolism were enriched in distinct clusters exhibiting the features of gradual gene activation and sustained repression, respectively. Therefore, these genes are differentially regulated during the regeneration, possibly leading to changes in the flow of amino acids and energy from enzyme proteins to plasma proteins in their synthesis. Thus, clustering analysis of expression patterns of functionally classified genes gave insights into mechanism and pathophysiology of liver regeneration.
Animals↗
Bezafibrate treatment: a new medical approach for PBC patients?
BACKGROUND: A new medical approach to primary biliary cirrhosis (PBC) has been desired. We investigated the feasibility of using combination ursodeoxycholic acid (UDCA)-bezafibrate therapy in patients with PBC nonresponsive to UDCA monotherapy. METHODS: During a 6-month period, 22 PBC patients with elevated serum alkaline phosphatase (ALP) despite UDCA monotherapy received either UDCA at 600 mg/day (control group) or UDCA at 600 mg/day plus bezafibrate at 400 mg/day (bezafibrate group). Each patient underwent detailed clinical and biochemical evaluation. RESULTS: During treatment, changes in ALP level were greater in the bezafibrate group than in the control group (P< 0.01). During and at the end of treatment, serum ALP levels were significantly lower than those before treatment in patients receiving UDCA plus bezafibrate (P< 0.05). At the end of the 6 months, normalization of serum ALP was observed in 5 of 11 (45.4%) patients given bezafibrate and in 2 of 11 (18.1%) patients not given bezafibrate (P< 0.16). Bile acid proportions during the combination therapy did not change. Pruritus disappeared in 1 of 7 bezafibrate-group patients with this symptom. CONCLUSIONS: UDCA at 600 mg/day plus bezafibrate at 400 mg/day may be considered as a new therapeutic option for patients with PBC.
Alkaline Phosphatase↗
Analysis of the genotype-determining region of hepatitis A viral RNA in relation to disease severities.
Although hepatitis A is still a considerable problem in Japan, correlation of genomic differences of hepatitis A virus (HAV) and the clinical status of hepatitis A has not been studied. To examine whether the HAV genotype is associated with the disease severity, we analyzed the HAV genotype-determining region in sera from patients with hepatitis A of various clinical degrees. Serum samples from 47 Japanese patients with sporadic hepatitis A from 4 different areas in Japan, including 8 with fulminant hepatitis, 11 with severe acute hepatitis (AHs), and 28 with AHs, were examined for HAV RNA. The 168 base pair sequence of the genotype-determining region, which is located at the VP1/2A junction, was amplified by reverse transcription-polymerase chain reaction, and the nucleotide sequence was determined by direct sequencing. By comparing sequences for VP1/2A, we determined that 44 of 47 cases examined were of subgenotype IA, two were of subgenotype IB, and one was of subgenotype IIIA. With respect to subgenotype IA strains, individuals who were infected between 1990 and 1996 tended to show similar sequences, whereas those infected between 1997 and 1999 showed sequences slightly different from those of the 1990-1996 cases. There were no apparent associations between disease severity and sequences of the genotype-determining region. Hepatitis A of our study was caused by a variety of subgenotype IA strains, consistent with the sporadic spread of infection. Disease severity was not associated with the nucleotide sequence of the HAV genotype-determining region.
Journal Article↗
Significance of prior hepatitis B virus infection in the development of hepatocellular carcinoma in patients with chronic hepatitis C.
To clarify the clinical significance of prior hepatitis B virus (HBV) infection in the development of C-viral hepatocellular carcinoma (HCC), we conducted two studies: (1) Two hundred thirty-four patients with C-viral HCC and 320 patients with C-viral chronic liver disease without HCC admitted to our hospital between 1990 and 1994 were analyzed for the association of hepatitis B core antibody (HBcAb) positivity with HCC by multivariate logistic regression analysis, and this revealed HBcAb positivity as an independent risk factor for development of HCC adjusted for age and sex. (2) Four hundred fifty-nine patients with biopsy-proven hepatitis C virus-related chronic liver disease between 1986 and 1998 were enrolled in the cohort study and followed for the development of HCC. During an average follow-up of 6.6 +/- 3.3 years, HCC developed in 63 patients, 37 of 160 patients positive for HBcAb and 26 of 299 patients negative for HBcAb. Multivariate Cox proportional regression analysis showed that the incidence of HCC increased by age, advanced stage of liver fibrosis, mean alanine aminotransferase value of more than 80 IU/liter, and positivity of HBcAb. Sustained virological responders after interferon therapy revealed a reduced risk for HCC development. In conclusion, prior HBV infection was shown to be one of the independent risk factors for development of HCC in C-viral chronic liver disease.
Carcinoma, Hepatocellular↗
Successful clearance of hepatitis B virus after allogeneic stem cell transplantation: beneficial combination of adoptive immunity transfer and lamivudine.
We report a 38-yr-old male with acute lymphocytic leukemia (ALL), whose serological tests for the hepatitis B virus (HBV) before transplantation showed a chronic carrier status, and a liver biopsy specimen revealed chronic liver injury because of HBV. The patient underwent allogeneic peripheral blood stem cell transplantation (PBSCT) from his sibling who was hepatitis B surface antibody (HBsAb) positive. He had received lamivudine treatment for the prophylaxis of HBV reactivation during cytotoxic chemotherapy, and lamivudine administration continued after transplantation. Successful engraftment was documented 3 wk after PBSCT, and clearance of the hepatitis B surface antigen (HBsAg) was observed 2 months after PBSCT. Liver function tests transiently showed a mild elevation of aminotransferases on day 25, although this returned to normal after the dose escalation of the immunosuppressive agent. We presume that the combination of adoptive immunity transfer by bone marrow transplantation (BMT) from an HBsAb-positive donor and antiviral drugs such as lamivudine is beneficial in clearing HBV in chronic carriers.
Adult↗
Influence of hepatitis B virus genotypes on the progression of chronic type B liver disease.
To investigate the hepatitis B virus (HBV) genotype-related differences in the progression of liver disease, 585 patients with chronic HBV infection including 258 with histologically verified chronic liver disease (CLD) and 74 with hepatocellular carcinoma (HCC) were examined. The mean ages of both patients with advanced fibrosis (F3 or F4) and with HCC were significantly older in genotype B than in genotype C patients (P =.018, P =.024, respectively). Both the hepatitis B e antigen (HBeAg) negativity rate at biopsy and the cumulative HBe seroconversion rate in patients with CLD were significantly higher in genotype B patients than genotype C patients (P <.01, P =.022, respectively). Multivariate analysis revealed that genotype B, presence of precore mutation, high ALT levels, and severe histologic activity were independent factors for HBe seroconversion. Among all the biopsy-proven CLD patients, the ratio of patients with advanced fibrosis in genotype B was significantly lower than that in genotype C (4/30 vs. 74/224, respectively; P =.034). This difference was more remarkable in younger patients (< or =45 years; 1/25 vs. 47/180, respectively; P =.020), and there was no difference in older patients (>45 years). The distribution of each genotype between CLD and HCC was very similar (B and C: 11.2% and 87.0% vs. 10.8% and 89.2%, respectively). In conclusion, our results suggest that, although the patients with genotype B experience earlier HBe seroconversion, slower progression of liver fibrosis, and slower development of HCC, the life-long risk of progression to advanced fibrosis and development of HCC may not differ among genotypes B- and C-related chronic liver disease.
Adult↗
Favorable prognosis of chronic hepatitis C after interferon therapy by long-term cohort study.
The prognosis of patients with chronic hepatitis C after interferon (IFN) therapy is still poorly defined. The present study evaluated the effect of IFN therapy on survival in a cohort of such patients. The study included 459 patients with biopsy-proven C-viral chronic liver disease who were followed for 8.2 +/- 2.9 years (range, 7-183 months). Survival status was examined by medical records or direct questionnaires. Fifteen (14%) of 104 IFN-untreated patients and 33 (9%) of 355 patients treated with IFN died during follow-up. Among the treated patients, 4 (3%) of 116 with sustained virologic response and 29 (12%) of 239 without sustained virologic response died. Liver-related death was shown in 32 (67%) patients, and hepatocellular carcinoma (HCC) caused 25 (52%) of the 48 deaths. Multivariate Cox proportional regression analysis revealed that IFN treatment decreased the risk ratio for overall death to 0.521 (confidence interval [CI]: 0.263-1.034) and for liver-related death to 0.208 (CI: 0.088-0.495) compared with untreated patients, and sustained virologic response showed a decrease in the risk ratio for overall death to 0.219 (CI: 0.068-0.710) and for liver-related death to 0.030 (CI: 0.003-0.267). IFN treatment showed no association with liver-unrelated death. Furthermore, the standardized mortality ratios for all causes of death and liver-related death were reduced in IFN-treated patients compared with untreated patients (1.4 vs. 2.0 for total death and 7.9 vs. 19.7 for liver-related death). In conclusion, the present data suggest that IFN therapy has a long-term clinical benefit for patients with chronic hepatitis C patients by reducing liver-related death, especially in patients with sustained virologic response.
Adult↗
Chronic graft-versus-host disease complicated by acute hepatitis B.
We observed a 45-year-old man with acute hepatitis B while receiving treatment of chronic graft-versus-host disease (GVHD) of the liver. When he developed a sudden elevation of serum aminotransferases 17 months after bone marrow transplantation, he was under immunosuppressive therapy consisting of cyclosporin A against chronic GVHD of the liver. Serologic tests for hepatitis B virus (HBV) showed no reactivation but de novo acute infection. The serum levels of aminotransferases after elevation of biliary tract enzymes increased mildly. However, icterus was not observed in his sequential course. A liver biopsy specimen revealed mild acute liver injury accompanied by slight degeneration of bile ducts. It is presumed that owing to immunosuppressive therapy, his liver dysfunction was relatively mild, and the hepatitis became quiescent without becoming serious. On the other hand, the serum of the patient remained hepatitis B surface antigen positive for more than 1 year after the onset of the hepatitis, which suggested chronicity of HBV infection.
Acute Disease↗
Analysis of T cell receptor variable regions and complementarity determining region 3 of infiltrating T lymphocytes in the liver of patients with chronic type B hepatitis.
OBJECTIVES: T cell receptor (TCR) variable regions and complementarity determining regions 3 (CDR3) of infiltrating T cells in the livers of patients with chronic hepatitis B were examined in detail. METHODS: TCR usage was examined by the inverse polymerase chain reaction in 2 hepatitis B e antigen-positive patients, one at an early stage and the other at an advanced stage. RESULTS: In 61 productively rearranged clones bearing TCRalpha genes in the liver of the patient with early stage chronic hepatitis B, the Valpha 7.2 gene segment was most frequently used (16.4%), while the other Valpha gene segments were used less frequently. All but one of the clones with the Valpha7.2 gene were joined with the Jalpha33 gene, and the CDR3 regions of these clones were the same length and similar in amino acid sequence. In contrast, in 68 productively rearranged clones from the liver of the patient with advanced stage disease, all Valpha gene segments were used less frequently, and combinations of the Valpha and Jalpha gene segments varied. CONCLUSIONS: Our data suggest a relatively restricted usage of TCR in the liver in early stage chronic hepatitis B.
Adult↗
Evaluation of the clinical usefulness of COBAS AMPLICOR HCV MONITOR assay (ver2.0): Comparison with AMPLICOR HCV MONITOR assay (ver1.0) and HCV core protein level.
The quantitation of serum levels of hepatitis C virus (HCV) RNA in chronic hepatitis C has been regarded as one of the most important indicators for the outcome of interferon (IFN) therapy. The AMPLICOR HCV MONITOR version 1.0 (AMPLICOR v1.0) assay is widely used for the evaluation of the HCV level. A new generation assay called the COBAS AMPLICOR HCV MONITOR version 2.0 (COBAS v2.0) assay, which is semiautomated and modified to amplify all genotypes equally, has been developed. The aim of this study was to evaluate the clinical relevance of the COBAS v2.0 assay in comparison with the AMPLICOR v1.0 assay and HCV core protein assay in patients with chronic hepatitis C before IFN therapy. HCV RNA was detectable in 230 cases (97.5%) and undetectable in 6 cases (2.5%) by the COBAS v2.0 assay. The RNA levels measured by the AMPLICOR v1.0 assay correlated significantly with those measured by the COBAS v2.0 assay, and the sensitivity of the new version 2.0 assay was better than that of version 1.0, especially in serotype 2. In relation to the outcome of IFN therapy, HCV RNA levels from virologically sustained responders by the AMPLICOR v1.0 assay were 82.3 +/- 22.9 kcopies/ml in serotype 1 and 36.9 +/- 13.4 kcopies/ml in serotype 2, and those from virologically nonsustained responders were 525.2 +/- 48.6 kcopies/ml in serotype 1 and 76.7 +/- 19.5 kcopies/ml in serotype 2. The rates of sustained response to <100 kcopies/ml were 34/63 (54.0%) in serotype 1 and 24/48 (50.0%) in serotype 2. A statistically significant virological response was seen in serotype 1 (P < 0.0001), but not in serotype 2. In contrast, the levels in virologically sustained responders by the COBAS v2.0 assay were 88.2 +/- 20.5 KIU/ml in serotype 1 and 136.8 +/- 40.1 KIU/ml in serotype 2, and those in virologically nonsustained responders were 608.8 +/- 48.4 KIU/ml in serotype 1 and 328.3 +/- 62.8 KIU/ml in serotype 2. The rates of sustained response to <100 KIU/ml were 33/60 (55.0%) in serotype 1 and 21/35 (60.0%) in serotype 2. Statistical significance in virological response was seen in both serotype 1 (P < 0.0001) and serotype 2 (P < 0.05). Although the sensitivity of the HCV core protein assay was lower than that with the COBAS v2.0 assay, the HCV core protein levels also correlated well with the results of the COBAS v2.0 assay. The HCV core protein levels of virologically sustained responders were 37.6 +/- 12.0 pg/ml in serotype 1, 81.3 +/- 37.0 pg/ml in serotype 2, and those of virologically nonsustained responders were 289.9 +/- 23.5 pg/ml in serotype 1, 191.4 +/- 32.1 pg/ml in serotype 2. This assay could predict the outcome of IFN therapy in both serotype 1 (P < 0.0001) and serotype 2 (P < 0.05). Thus, both the COBAS v2.0 assay and the HCV core protein assay showed that the viral load was an indicator of virologically sustained response in serotype 2 and in serotype 1.
Adolescent↗
Hepatic graft-versus-host disease resembling acute hepatitis: additional treatment with ursodeoxycholic acid.
Hepatic graft-versus-host disease (GVHD) is a frequent complication after bone-marrow transplantation (BMT). The disease is often refractory to immunosuppressive therapy. We present a 30-year-old Japanese male, who developed an abrupt elevation of aminotransferases, on day 135 after allogeneic BMT. A liver biopsy specimen revealed degeneration of the small bile ducts and portal fibrosis, and the diagnosis of chronic hepatic GVHD was confirmed. No manifestation of chronic GVHD was observed except liver dysfunction. The administration of prednisolone (PSL) and cyclosporin (CsA) ameliorated laboratory data to a degree, but they did not return to normal. Treatment with ursodeoxycholic acid (UDCA), subsequently added to the immunosuppressive therapy, apparently normalized the levels of biliary tract enzyme and total bilirubin. His liver function test completely returned to normal on day 260. We believe that it is worthwhile to administer UDCA as an additional treatment for not only common hepatic GVHD but also atypical cases presenting as acute hepatitis.
Acute Disease↗
[A case of steatohepatitis associated with tamoxifen].
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Antineoplastic Agents, Hormonal↗
Acute hepatitis C virus infection, 1986-2001: a rare cause of fulminant hepatitis in Chiba, Japan.
BACKGROUND/AIMS: Hepatitis C virus (HCV) is the most common cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. It is controversial whether HCV causes fulminant hepatitis. METHODOLOGY: To determine the clinical features and etiology of acute hepatitis and fulminant hepatitis in Japan, an endemic area of hepatitis C, between 1986 and 2001 inclusively, a retrospective study of consecutively referred patients was performed. Two hundred and sixty-three patients admitted to a liver clinic after diagnosis of acute hepatitis or fulminant hepatitis, were evaluated. RESULTS: We found 181 cases of acute hepatitis and 82 cases of fulminant hepatitis/late onset hepatic failure. No cases of fulminant hepatitis were positive for HCV RNA. Only three cases had positive anti-HCV antibody, and they were thought to indicate past HCV infection. The main cause of infection in these three patients was hepatitis A virus in one,hepatitis B virus in one, and drugs in the remaining one. HCV did not seem to be the major cause. The three cases died without receiving liver transplantation. CONCLUSIONS: It was revealed that fulminant hepatitis C rarely occurs in Japan, as well as in the USA and European countries. Investigators should search for other causes in fulminant cases presenting an HCV marker.
Adult↗
Prevalence of obesity in patients with acute hepatitis; is severe obesity a risk factor for fulminant hepatitis in Japan?
BACKGROUND/AIMS: The prevalence of obesity in acute convalescent hepatitis and fulminant hepatitis has not been reported. The aim of this study was to investigate whether obesity affected the disease severity in Japanese patients with acute hepatitis. METHODOLOGY: 31 non-severe acute hepatitis (NS-AH) and 24 severe acute hepatitis and 14 fulminant hepatitis patients (S-AH) between January 1995 and December 2001 were analyzed retrospectively. Height and weight were used to calculate the body mass index (BMI) in these 69 patients. RESULTS: Mean height, weight and BMI were not significantly different between S-AH and NS-AH patients. Two severely obese (BMI greater than 35kg/m2) patients had developed S-AH. CONCLUSIONS: Severe obesity may be one of the prognostic factors in acute hepatitis. Further studies are needed.
Acute Disease↗
Acute-onset autoimmune hepatitis resembling acute hepatitis: a case report and review of reported cases.
We report a 54-year-old Japanese man, whose ALT level was 1689 IU/L, without increased gamma-globulin level or autoantibodies. He could not be diagnosed as autoimmune hepatitis (AIH) using scoring systems, and his liver function became normalized after steroid treatment. Recently, AIH with acute presentation of disease and acute-onset AIH without bridging fibrosis have been increasingly reported but cases without the character of increasing gamma-globulin level or autoantibodies before immunosuppressive treatment are extremely rare. This is the third such case report in the literature.
Acute Disease↗