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T Monna

Publications and source records attributed to T Monna.

At least 19 recordsLinked to original sources
PubMed2000

Contribution of hepatitis C virus to the progression of alcoholic liver disease.

BACKGROUND: We determined hepatitis C virus (HCV) antibody, HCV RNA, and genotype in patients with alcoholic liver disease and studied the involvement of HCV in alcoholic liver disease. Additionally, we used the histological activity index (HAI) to study the influence of HCV on the severity of inflammation. METHODS: The subjects were 143 patients with alcoholic liver disease: 7 with fatty liver (FL), 18 with hepatic fibrosis (HF), 24 with alcoholic hepatitis (ALH), 39 with chronic hepatitis (CH), 42 with liver cirrhosis (LC), and 13 with hepatocellular carcinoma (HCC). The HCV RNA positivity rate in each type of disease was 0/7 (0%), 1/18 (6%), 2/24 (8%), 27/39 (69%), 24/42 (57%), and 7/13 (54%), respectively. It was high in the advanced hepatic lesions. RESULTS: Clinically, the serum hepatic function tests after abstinence from drinking improved significantly in the HCV RNA negative patients compared with the positive patients. The proportion of genotype II in each type of disease was 0/0, 0/1 (0%), 1/2 (50%), 18/27 (67%), 18/24 (75%), and 7/7 (100%), respectively. It became high with the advance of pathophysiology. The HCV RNA amount stood at 7.5 +/- 0.4 [log (copies/ml)] in CH, 7.9 +/- 0.4 in LC, and 8.4 +/- 0.8 in HCC, with a statistically significant difference between CH and HCC. However, we found no changes in the HCV RNA amount due to abstinence from drinking. The HAI score was high in the HCV RNA positive patients, but several cases in the HCV RNA negative group showed severe inflammatory changes. Therefore, judging the presence or absence of HCV RNA with the HAI score alone was considered difficult. CONCLUSIONS: These results suggest that HCV, particularly genotype II, plays an important role in the advance of disease to LC and HCC in heavy drinkers.

Adult↗
PubMed1999

Significant role of apoptosis in type-1 autoimmune hepatitis.

We used the terminal deoxyribonucleotidyl transferase-mediated deoxyuridine triphosphate-digoxigenin nick-end labeling (TUNEL) method to detect apoptosis, and immunohistochemical staining for molecules related to apoptosis, a marker of cell proliferation, and surface markers of lymphocytes to examine 20 patients with autoimmune hepatitis (AIH). Confluent hepatic necrosis was frequently found, in which rosette formation of hepatocytes and ductular proliferation were common. TUNEL staining and staining for Lewis Y antigen, Bax protein, and Fas antigen were found in biliary epithelial cells in bile ducts and proliferating atypical bile ductules in regions of confluent necrosis with severe lymphocytic infiltration. TUNEL staining and staining for Lewis Y antigen and Bax protein were found in rosette-forming hepatocytes. Many hepatocytes in lobules without injury were stained for proliferating cell nuclear antigen (PCNA). bcl-2 oncoprotein was found in many lymphocytes surrounding proliferating atypical bile ductules and rosette-forming hepatocytes in regions of confluent necrosis, in which CD20 and OPD 4 were found. Apoptosis of both hepatocytes in rosette arrangement and biliary epithelial cells in bile ducts and proliferating atypical bile ductules may play a role in progression of AIH as well as confluent hepatic necrosis.

Adult↗
PubMed1998

Characteristics of patients with hepatitis C virus with and without GB virus C/hepatitis G virus co-infection and efficacy of interferon alfa.

GB virus C/hepatitis G virus (GBV-C/HGV) infection seems to be common among patients with hepatitis C virus (HCV) infection. We studied retrospectively the proportions of patients with GBV-C/HGV RNA and antibodies to the GBV-C/HGV second envelope protein (anti-E2) among 149 subjects with chronic hepatitis C who had received interferon alfa. The clinical characteristics of patients with GBV-C/HGV RNA or anti-E2 were examined, as was the efficacy of the treatment. Stored serum specimens were tested for GBV-C/HGV RNA by the reverse transcription polymerase chain reaction and for anti-E2 by an enzyme-linked immunosorbent assay. Of the 149 patients before therapy, 8 (5%) had GBV-C/HGV RNA only, 72 (48%) had anti-E2 only, and 4 (3%) had both. The mean age of patients with GBV-C/HGV RNA (some with anti-E2) was significantly less than that of patients with anti-E2 only. Results of laboratory and histological evaluations were not different depending on the presence of GBV-C/HGV RNA or anti-E2. The GBV-C/HGV RNA titer decreased during therapy in all 12 patients with GBV-C/HGV RNA; only 4, with a low titer before therapy and with anti-E2 detected at some time, had sustained clearance of GBV-C/HGV. Our results suggested that half of the patients with chronic hepatitis C had been exposed to GBV-C/HGV, but in almost all, the virus had been cleared; also, even chronic GBV-C/HGV infection did not affect the severity of the disease arising from HCV. Interferon alfa treatment was sometimes effective against GBV-C/HGV, and anti-E2 may be associated with clearance of GBV-C/HGV.

Adult↗
PubMed1998

Longitudinal changes of bone mineral content with age in patients with cirrhosis of the liver.

Bone disorders are associated with cirrhosis. Knowledge of the natural course of bone changes in cirrhosis could help in decision-making about medical treatment. We carried out one measurement of bone mineral density (BMD) in 184 Japanese patients (98 men and 86 women) with cirrhosis by dual-energy X-ray absorptiometry. Differences in BMD values means +/- SD between the 98 cirrhotic men and 283 healthy men of the same age reported in another study were not significant. In the 86 cirrhotic women, BMD tended to show a greater decrease with age than in healthy controls reported elsewhere. Differences in BMD values (means +/- SD) between 622 healthy women reported elsewhere and our patients were not significant for women up to age 60 years, but at 60 years or more, the mean BMD in cirrhotic women (0.692 +/- 0.100) was lower than that in healthy women (0.749 +/- 0.101; P < 0.01). In 61 of the 184 patients (31 men and 30 women), the bone mineral content (BMC) of lumbar vertebrae was measured at least twice, at intervals of 10-72 months. In this longitudinal part of the study, the group mean of estimated annual change for cirrhotic men was -0.4%, close to that of healthy men (-0.2%). This mean in cirrhotic women was -2.8%, significantly different from that of healthy women (-1.1%; P < 0.05). As expected, cirrhotic women were the most likely to lose BMC, and many needed prompt treatment.

Absorptiometry, Photon↗
PubMed1998

Relationship between glutathione and polyamine metabolism after partial hepatectomy in alcohol-treated rats.

In a liver regeneration inhibiting model after partial hepatectomy in rats, we determined hepatic glutathione concentration and studied its relation with polyamine, an indicator of liver regeneration. Experiment 1: Male ODS rats and Wistar rats as control were maintained with vitamin C-deficient diets for 2 weeks. In the alcohol group, 3 g/kg of ethanol was administered orally 1 hr before partial hepatectomy. Experiment 2: Wistar rats were divided into four groups, according to the presence or absence of alcohol and vitamin E (VE), and a 6-week pair-feeding was done. As for partial hepatectomy, about 70% of the total liver was excised. As a result, in experiment 1, hepatic glutathione levels were significantly decreased by acute alcohol administration in both ODS and Wistar rats, and its level of alcohol administration group of ODS rats was the lowest. Hepatic ornithine decarboxylase activity and putrescine level 4 hr after partial hepatectomy showed almost a similar behavior, being the lowest in the alcohol administration group of ODS rats. In experiment 2, hepatic glutathione level showed no influence by chronic alcohol administration, but was the lowest in the VE-deficient alcohol administration group. Hepatic ODC activity and putrescine level 4 hr after partial hepatectomy showed no influence by chronic alcohol administration, but was the lowest in the VE-deficient alcohol administration group. These results clarified that intrahepatic glutathione levels before partial hepatectomy were decreased in the models in which hepatic ODC activities after surgery were suppressed.

Animals↗
PubMed1998

Types of organic solvents used in workplaces and work environment conditions with special references to reproducibility of work environment classification.

A survey of solvent was conducted for 196 unit work areas in 95 plants in 1994 to 1996 in Hiroshima Prefecture, Japan. The survey had been repeated every 6 months (i.e., twice a year) during the 3-year period. Sampling and analysis of the solvent vapors were carried out after national protocols set by the regulation. Toluene was most frequently detected regardless of the type of solvent work (except for degreasing), whereas the second- and the third-most common solvents varied depending on the type of solvent works. Among chlorinated hydrocarbon solvents for degreasing, dichloromethane was most widely used. Solvent concentrations were generally low as none of the median concentrations exceeded corresponding Administrative Control Levels set by the regulation, either individually or even when the assumption of additiveness was applied. Among the 1176 cases analyzed, 80% of the unit work areas were evaluated as adequate (i.e., classified as Class I). Furthermore, about 57% stayed in Class I throughout the 3 years, suggesting that solvent exposure conditions were generally quite stable. In regulatory evaluation by classification, A-sampling was decisive in most cases, whereas the role of B-sampling was limited.

Chi-Square Distribution↗
PubMed1997

Induction of apoptosis in a human hepatocellular carcinoma cell line by a neutralizing antibody to transforming growth factor-alpha.

A cell line derived from a Japanese man with hepatocellular carcinoma was established in culture and designated OCUH-16. The cell line has the morphological and chromosomal features of hepatocellular carcinoma cells and has a short doubling time (approximately 33 h). OCUH-16 cells were shown to express transforming growth factor-alpha (TGF-alpha) in addition to albumin, DNA polymerase-alpha, c-JUN, and the retinoblastoma gene product. Electron microscopy revealed TGF-alpha immunoreactivity associated with the cell membrane, but TGF-alpha was not detected in medium conditioned by OCUH-16 cells by enzyme-linked immunosorbent assay. Reverse transcription and polymerase chain reaction analysis revealed the presence of TGF-alpha messenger RNA in these cells. Culture of OCUH-16 cells in the presence of a neutralizing antibody to TGF-alpha inhibited cell proliferation and induced many cells to undergo apoptosis (programmed cell death). These observations suggest that endogenous TGF-alpha is necessary for OCUH-16 cell growth.

Antibodies, Monoclonal↗
PubMed1997

Expression of cytochrome P450 isoforms in rat hepatic stellate cells.

The current study evaluated the expression and the inducibility of cytochrome P450 isoforms in rat hepatic stellate cells (HSCs). Immunoblotting study revealed that HSCs expressed several P450s and CYP2C11, 3A2, and 2D1 were major isoforms. The levels of CYP2B1, 2C11, 2D1, 2E1, and 3A2 in HSCs were 14 - 38% of those in hepatocytes. CYP1A2 content was similar in each cell type. These P450 levels in HSCs gradually decreased during culture as seen in hepatocytes; the level of CYP3A2 rapidly, whereas that of CYP2D1 slowly decreased. Phenobarbital, a typical inducer of CYP3A2 and 2B1 increased CYP3A2 level as well, but had less potency in the induction of CYP2B1 in HSCs. These results indicate that multiple P450 isoforms were present in HSCs, but their content and inducibility were different between HSCs and hepatocytes.

Animals↗
PubMed1997

Prevalence of GBV-C and hepatitis G virus variants in patients with fulminant hepatic failure in Japan.

BACKGROUND/AIMS: Whether GB virus C and hepatitis G virus participate in fulminant hepatic failure is controversial. We studied the prevalence of the viral RNA in 48 patients. There were possible routes of infection, including blood transfusion, in 22 patients (group 1), and no risk factors in the other 26 (group 2). METHODS: We assayed serum viral RNA with reverse transcription and nested polymerase chain reactions. Serum was obtained at admission, and after transfusion in group 2. RESULTS: Five (10%) serum samples from group 1 at admission had viral RNA of the 5'-untranslated region, and three of these samples had viral RNA of the NS3/helicase region. All five patients had transfusions before sampling. Two (4%) samples from group 2 were positive by both tests only after transfusion. Of two patients, one with non-A-E fulminant hepatic failure survived. Her serum alanine aminotransferase did not increase further after transfusion, but did stay above the reference range during follow-up. The other patient, with infection with hepatitis B virus detected at admission, died. After transfusion, his alanine aminotransferase did not increase further. Partial nucleotide sequences of GB virus C and hepatitis G virus from three fulminant hepatic failure patients and five control patients with chronic hepatitis C were compared with published sequences. A viral variant causing fulminant hepatitis, suggested elsewhere, was not found, nor was all of a characteristic pattern of six mutations found elsewhere. CONCLUSIONS: GB virus C and hepatitis G virus may cause hepatitis, but probably not severe hepatitis such as fulminant hepatic failure.

Base Sequence↗
PubMed1997

Detection by ligase chain reaction of precore mutant of hepatitis B virus.

The clinical diagnosis of infection with the most common precore mutant of hepatitis B virus (HBV), that with a point mutation from guanine to adenine at nucleotide 83 in the precore region, is important because the disease may progress rapidly despite interferon therapy. A practical method to detect this mutant is needed. With the ligase chain reaction (LCR), target DNA sequences can be amplified and single base mutations can be detected. We tried to detect mutant HBV by the LCR alone, but the limit of detection (10(9) copies per tube) was too high. To increase the sensitivity, we used the LCR on DNA already amplified by the polymerase chain reaction (PCR), and tested serum samples from 23 subjects with chronic HBV infection for mutant and wild-type HBV. As few as 10(2) copies per tube could be detected. The results corresponded with the results of nucleotide sequencing for 22 of the 23 patients. The ratio of clones of mutant and total viruses was estimated for each individual by PCR-coupled LCR. Seroconversion could be identified earlier in the illness by an increase in this ratio than by the decrease in HBeAg. We also tested serum samples from 11 patients with acute liver failure by PCR-coupled LCR. Mutant HBV was detected at a low ratio in all 4 patients with acute self-limited hepatitis (AH). Wild-type HBV coexisted with mutant HBV in 6 of 7 patients with fulminant hepatitis (FH), and the mean ratio of mutant to total HBV was significantly higher than that in AH. PCR-coupled LCR could be used to detect mutant HBV and to estimate the ratio of mutant to total viruses.

Adolescent↗
PubMed1997

Hepatic expression of c-Myb in chronic human liver disease.

C-Myb is a sequence-specific DNA binding protein that regulates the expression of genes involved in cell proliferation and differentiation. The present study was designed to elucidate the role of c-Myb in the pathogenesis of chronic liver disease by an immunohistochemical approach. In normal (control) livers, few or no hepatic cells were positive for c-Myb. In livers from patients with chronic viral hepatitis, positive staining for c-Myb was found not only in spindle-shaped mesenchymal cells in expanded portal areas, but also in perisinusoidal cells (PSCs) within liver lobules. In cirrhotic livers, a few PSCs within lobules were positive for c-Myb, while no staining was seen in fibrous septa. Immunoelectron microscopy revealed that c-Myb-positive PSCs displayed morphological features of hepatic stellate cells. Other sinusoidal lining cells including Kupffer cells and sinusoidal endothelial cells, as well as hepatocytes, were all negative for c-Myb. Dual c-Myb/alpha-smooth muscle actin (alphaSMA) staining revealed that more than 97% of c-Myb-positive cells were alphaSMA-positive. Moreover, dual c-Myb/proliferating cell nuclear antigen (PCNA) staining showed that approximately 70% of c-Myb-positive cells also expressed PCNA. The labeling index (LI) (number of c-Myb-positive cells/0.1 mm2) significantly correlated with serum transaminase concentrations and increased in parallel with the disease activity. However, the LI showed no correlation with the degree of fibrosis. These results suggest that c-Myb may be involved in stellate cell activation and proliferation in chronically diseased human livers, and that the level of c-Myb expression is associated with the activity of chronic hepatitis.

Actins↗
PubMed1997

Acetaldehyde as well as ethanol is metabolized by human CYP2E1.

Acetaldehyde was oxidized by rat and human hepatic microsomes in the presence of NADPH. We designated this NADPH-dependent oxidation system MAOS (microsomal acetaldehyde-oxidizing system), to distinguish it from the NAD-dependent acetaldehyde oxidation system of acetaldehyde dehydrogenase in mitochondria and cytosol. This activity was increased 2.3-fold by giving rats ethanol. Judging from the Vmax/Km values, the metabolic capacity of rat hepatic microsomes for MAOS activity was increased 24-fold by ethanol. The acetaldehyde oxidation activity of eight forms of purified rat cytochrome P450 was investigated in a reconstituted system. CYP2E1 had the highest level, followed by CYP1A2 and 4A2. Immunoinhibition studies showed that an anti-CYP2E1 antibody inhibited 90% of the MAOS activity in rats given ethanol. NADPH-dependent acetate formation was 12% or 33.6% of the NAD-dependent acetate formation in liver homogenates of control rats and those treated with ethanol, respectively. We investigated human MAOS activity further. Among the 10 forms of human cytochrome P450 expressed in yeast, CYP2E1 had especially high acetaldehyde oxidation activity. The correlation of MAOS activity with the levels of immunoreactive CYP2E1 in individual human microsomes was highly significant (r2 = 0.88, P < .01). These results indicate that hepatic CYP2E1 mainly contributes to MAOS in rats and humans, the pathway of which may play an alternative role against acetaldehyde in the liver after alcohol consumption together with acetaldehyde dehydrogenase in the metabolism of acetaldehyde.

Acetaldehyde↗
PubMed1996

Metabolism of acetaldehyde to acetate by rat hepatic P-450s: presence of different metabolic pathway from acetaldehyde dehydrogenase system.

NADPH-dependent activity of acetaldehyde oxidation was investigated in microsomes by assaying [14C]acetic acid produced from [14C]acetaldehyde with ion-exchange column. Rat hepatic microsomes exhibited acetaldehyde oxidation activity in the presence of NADPH. This activity was induced 2-fold by the treatment of rats with ethanol. We designated this NADPH-dependent oxidation system as microsomal acetaldehyde-oxidizing system (MAOS), to distinguish from the NAD-dependent acetaldehyde oxidation system by acetaldehyde in mitochondria and cytsol. We further investigated essential enzymes contributing to MAOS activity. Acetaldehyde oxidation activity was investigated in eight forms of purified P-450 in a reconstituted system. Cytochrome P-450 (CYP) 2E1 had the highest oxidation activity and CYP1A2 and CYP4A2 had the next highest activity. Other forms had low activity. To assess the contribution of these forms to MAOS activity, immunoblot was done. CYP2E1 was induced 2-fold by ethanol treatment, but CYP1A2 and CYP4A2 were not reflecting the MAOS activity increased by ethanol treatment. These results suggest that CYP2E1 is the essential enzyme in the MAOS of rats.

Acetaldehyde↗
PubMed1996

Effect of vitamin E deficiency on inhibition of liver regeneration by long-term administration of alcohol.

The effects of vitamin E (VE) deficiency on liver regeneration suppressed by long-term administration of alcohol were studied. Male rats were divided into two groups: the alcohol group and the control group. In addition, each group was subdivided into two groups according to the presence or not of VE. Altogether, four groups were provided: a group maintained on the VE-deficient alcohol diet (group EA), a group maintained on the VE-deficient control diet (group EC), a group maintained on the ordinary alcohol diet (group A), and a group maintained on the ordinary control diet (group C). After pair-feeding for 6 weeks, partial hepatectomy was performed to determine the omithine decarboxylase (ODC) activity, polyamine levels, lipid peroxide levels, and DNA synthesis, DNA synthesis at 24 hr after partial hepatectomy was suppressed significantly in the alcohol administration group, regardless of the presence or not of VE DNA synthesis at 48 hr after partial hepatectomy tended to show low values in group EA, compared with group A. As for the hepatic ODC activity, group EA showed the lowest value at 4 hr after partial hepatectomy. Of polyamines, the putrescine level in group EA at 4 hr after partial hepatectomy was significantly low, compared with the other three groups. The levels of spermidine and spermine decreased by long-term administration of alcohol, but the effect of VE deficiency was not found. The lipid peroxide level increased significantly in the VE-deficient diet administration group, but the effect of alcohol administration was not found. These results suggested that the decrease in putrescine after ODC suppression by VE deficiency in addition to the decrease in spermidine and spermine caused by long-term alcohol administration were concerned with suppression of DNA synthesis later.

Animals↗
PubMed1996

Microsomal ethanol oxidizing system activity by human hepatic cytochrome P450s.

To assess the contribution of cytochrome P450 (P450) to the microsomal ethanol oxidation system (MEOS) in humans, we examined ethanol oxidization activity in human hepatic microsomes and multiple forms of human hepatic P450s expressed in B-lymphoblastoid cells. Acetaldehyde produced by the MEOS was converted into a fluorescent derivate with cyclohexane-1,3-dione and analyzed by high-performance liquid chromatography using a fluorescence detector. The ethanol oxidation activity of seven forms of human P450s was investigated. P450s 2E1 and 1A2 formed acetaldehyde at high rates. In immunoinhibition studies, anti-P450 2E1 antibody inhibited the ethanol oxidation activity of human hepatic microsomes by 54%, and anti-P450 1A2 antibody inhibited ethanol oxidation activity by 21%. 7,8-Benzoflavone, an inhibitor of P450 1A forms, also inhibited this activity by 38%. The correlation of ethanol oxidation activity with the levels of immunoreactive P450 2E1 in individual human microsomes was highly significant (r = 0.91, P < .001), and the correlation of ethanol oxidation activity with the levels of P450 1A2 was also highly significant (r = 0.87, P < .001). The Km values of P450s 2E1 and 1A2 for ethanol oxidation were 16.5 and 23.6 mM, respectively. These results indicated that P450 2E1 was a major contributor to the MEOS in humans; however, P450 1A2 was considered to play an important role in the MEOS.

Adolescent↗
PubMed1996

[Effects of chronic ethanol feeding on lipid composition of rat liver plasma membrane--changes of membrane by acute ethanol loading or its withdrawal in vivo].

The effects of chronic ethanol feeding on lipid composition of rat liver plasma membrane were studied by following ethanol loading or its withdrawal in vivo. Male Wistar rats were pair-fed by a liquid diet containing ethanol as 36% of energy or an isocarolic amounts of glucose for 6 weeks. Chronic ethanol feeding resulted in an increase of cholesterol content and the cholesterol/phospholipid molar ratio in liver plasma membrane compared with pair-fed control rats. Acute ethanol (3 g/kg body weight) orally loading to rats fed ethanol chronically did not change any lipid composition of liver plasma membrane. However, withdrawal of ethanol for 2 days led cholesterol content and the cholesterol/phospholipid molar ratio of liver plasma membrane to be normal values. These data indicated that chronic ethanol feeding produced membrane alterlation that induced resistance to ethanol-induced membrane structural disordering (membrane tolerance), and that this alterlation resulted in a homeoviscous adaptation of liver plasma membrane.

Alcoholism↗