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T Okanoue

Publications and source records attributed to T Okanoue.

At least 127 records · Page 7Linked to original sources
PubMed1990

Vitamin K (menaquinone-4) metabolism in liver disease.

We measured menaquinone-4 (MK-4) and MK-4 epoxide concentrations in plasma and liver tissue after intravenous injection of 200 micrograms/kg MK-4 in 42 patients who underwent hepatectomy. They were classified into normal (N; n = 10), chronic hepatitis (CH; n = 12), and liver cirrhosis (LC; n = 20) groups, on the basis of the diagnosis given by the pathologist after examining resected liver specimens. The plasma MK-4 epoxide concentration reached maximum level (Cmax) 60 min after MK-4 injection. The Cmax in groups LC and CH were 85.9 and 126.3 nmol/l, respectively, which is significantly reduced compared with that of group N (184.4 nmol/l) (p less than 0.01 and p less than 0.05, respectively). The MK-4 concentrations in liver tissues of 24 patients 60 min after MK-4 injection were 2.77 in group N, 3.79 in group CH, and 3.83 nmol/g in group LC, and the MK-4 epoxide concentrations were 4.01, 3.09, and 2.62 nmol/g in the respective groups. Consequently, the ratio of MK-4 epoxide to total MK-4 (MK-4 + MK-4 epoxide) in groups CH and LC was significantly lower than in group N (p less than 0.01). It is concluded that the Cmax of MK-4 epoxide after MK-4 injection may serve as an indicator of liver function and that the low ratio of MK-4 epoxide to total MK-4 in the liver shows impairment in vitamin K metabolism.

Carcinoma, Hepatocellular↗
PubMed1990

[The expression of ras p21 product in hepatocellular carcinoma].

To elucidate the cell biological significance of ras oncogene, the expression of ras-p21 was analyzed in 53 cases of liver tissues including 34 cases of hepatocellular carcinoma (HCC), by using immunohistochemical method. In result, 22 (65%) cases of 34 HCC and 34 (79%) cases of 43 liver cirrhosis were positive for p21, whereas all of chronic hepatitis and normal livers were negative. Especially, comparative study between the expression of p21 and clinicopathological background of HCC revealed that p21 was prominently expressed in well differentiated form, nodular type, small liver cancer, and the cases showing AFP levels below 400 ng/ml. From these results, it was indicated that ras oncogene might play an important role in malignant transformation of hepatocytes or differentiation of HCC.

Carcinoma, Hepatocellular↗
PubMed1989

Measurement of vitamin K in human liver by gradient elution high-performance liquid chromatography using platinum-black catalyst reduction and fluorimetric detection.

A sensitive and precise method for measuring endogenous phylloquinone (K1) and menaquinone (MK-n) in human liver was developed, based on gradient elution high-performance liquid chromatography using platinum-black catalyst reduction and fluorimetric detection. Subnanogram levels of vitamin K compounds in 1 g of liver specimen were detectable. We measured vitamin K concentrations in 38 human resected livers. K1 and MK-4 to MK-13 were detected. The concentrations of MK-10 to MK-12 in livers with chronic hepatitis (n = 10) and cirrhosis (n = 22) were significantly lower than in normal livers (n = 6). It is suggested that the decreased concentrations indicate functional damage of the hepatocytes.

Catalysis↗
PubMed1989

Immunoelectron microscopic localization of actin in normal and cholestatic rat hepatocytes.

The immunoelectron microscopic localization of actin in hepatocytes was studied in normal, common bile duct-ligated, and phalloidin treated rats. We used the low temperature embedding procedure with Lowicryl K4M and protein A-gold technique was applied to demonstrate the localization of actin. The tissues embedded in Lowicryl K4M at low temperature provided good preservation of ultrastructure and antigenicity of actin. In control rats bile canaliculi were clearly visualized and most of the gold particles were observed on the bile canalicular microvilli, at the pericanalicular ectoplasm, at the cell border, and on the sinusoidal microvilli. In common bile duct-ligated rats and phalloidin treated rats, pericanalicular ectoplasm was thickened and many gold particles were seen there.

Actins↗
PubMed1989

Changes in serum bile acid composition in relation to histological findings after liver transplantation in piglets.

Changes in the composition of serum bile acids were investigated after orthotopic liver transplantation in piglets. Serum levels of all bile acid components rapidly increased during the anhepatic phase and then quickly decreased, returning to the preoperative state within 6 h of revascularization of the allograft. In the animals in which extrahepatic biliary stenosis was a complication, serum total bile acids (TBA) increased remarkably. A marked increase of hyocholic acid and marked decrease of hyodeoxycholic acid were noted; as percentages of TBA, the average levels per day were 91.3 +/- 1.3 and 5.0 +/- 1.3%, respectively. No change in chenodeoxycholic acid (CDCA) was observed. In the animals suffering acute rejection without extrahepatic biliary stenosis, serum TBA increased slightly and the percentage of CDCA rose, the average level being 29.6 +/- 1.5%. These results suggest that the measurement of the composition of serum bile acids may serve as a useful means of assessing allograft function after liver transplantation.

Animals↗
PubMed1989

[Evaluation of plasma PIVKA-II as a new marker for hepatocellular carcinoma].

We have measured the plasma PIVKA-II levels in 188 cases of various liver disease with HCC and malignant diseases in other organs by an EIA, using a monoclonal antibody (E-1023 kit, Eisai), and also have measured the plasma vitamin K levels in cases of HCC and cholestasis by an HPLC. Plasma PIVKA-II was detected in many cases of HCC (67%, 35 of 52 cases) and cholestasis (60%, 6 of 10 cases). In contrast, the positivities of PIVKA-II in the other diseases including benign liver diseases were very low. Combination assays of PIVKA-II and vitamin K revealed that PIVKA-II correlates with vitamin K in cholestasis but not in HCC, suggesting that PIVKA-II in HCC does not depend on a systemic deficiency of vitamin K. From these results, it was concluded that PIVKA-II is a reliable marker which can reflect the clinical course of HCC.

Adult↗
PubMed1988

Intermediate filaments of hepatocytes and biliary epithelial cells in bile duct obstruction: transmission and scanning electron microscopy study.

The cytoskeletons of hepatocytes and biliary epithelial cells in bile duct ligated rate livers were investigated by transmission and scanning electron microscopy. The three dimensional organization of the intermediate filaments (IFs) of hepatocytes and biliary epithelial cells was clearly demonstrated by scanning electron microscopy. Cell borders and dilated bile canaliculi were well preserved after perfusion with detergent solution. A very dense filamentous network of IFs was seen throughout the cytoplasm, especially around the dilated bile canaliculi and at the cell borders. IFs in biliary epithelial cells were more numerous compared with hepatocytes. Morphometric analysis showed that the IFs of hepatocytes significantly (p greater than 0.001) increased in amount in bile duct ligated rats. The IFs of biliary epithelial cells showed no significant changes in bile duct ligated rats compared to controls. These results suggest that the increase in IFs in hepatocytes results from the adaptation of the hepatocytes to the stress imposed by bile duct ligation. It may be that the resulting intracanalicular pressure and back diffusion of bile induces a metaplastic change in hepatocytes so that they acquire more IFs to function like the bile duct epithelium to conduct bile flow.

Animals↗
PubMed1988

Scanning electron microscopy of the hepatocyte cytoskeleton in human liver tissue.

Portions of eight human livers taken by wedge biopsy or needle biopsy were extracted with 0.5% Triton X-100 and then studied by scanning electron microscopy and immunoelectron microscopy. The wedge-biopsy specimens were perfused with the detergent solution. Needle-biopsy specimens were quickly frozen and cracked and then the cracked tissue was immersed in the detergent solution. The three-dimensional filament network of hepatocytes was visualized. A dense network which consisted of intermediate filaments and microfilaments was observed within the cytoplasm of hepatocytes. These filaments were better preserved in the needle biopsies which were quick-frozen and cracked before extraction than in the wedge biopsies. Variation in the amount of the cytoskeletal filaments was less prominent in the hepatocytes treated by rapid freezing. It is concluded that freeze-cracking is the most favorable method for the study of cytoskeletal pathology in various liver diseases in man.

Biopsy↗
PubMed1988

Deleterious effects of splanchnic congestion on hepatic energy metabolism following repeated portal triad cross-clamping in dogs.

Thirty minutes of warm hepatic ischemia produced by portal triad cross-clamping was repeated five times at 30-minute intervals in three groups of five dogs each: Group A was subjected only to portal triad cross-clamping; Group B received simultaneous clamping of the celiac axis and the superior mesenteric artery; and Group C had a simultaneous splenojugular shunt. The arterial blood ketone body ratio (acetoacetate/beta-hydroxybutyrate: KBR), reflecting the NAD+/NADH ratio in liver mitochondria, decreased significantly after each cross-clamping in all groups. After the first declamping, there was no significant difference in the recovery rate of the KBR among the three groups. After the second declamping, the recovery rate in Group A decreased significantly compared with the rates of Groups B and C (P less than 0.05). After the fourth declamping, the recovery rate in Group B was significantly lower than that of Group C (P less than 0.05). The hepatic energy charge [(ATP + 1/2ADP)/(ATP + ADP + AMP)] 30 minutes after the fifth declamping decreased significantly to 0.75 +/- 0.01 in Group A, compared with 0.84 +/- 0.01 in Group C (P less than 0.01). The lactate and total free plasma amino acid levels in the arterial blood increased significantly in the order of Groups A, B, and C. It is suggested that the inflow of stagnant portal venous blood to ischemic liver impairs hepatic energy metabolism.

Amino Acids↗
PubMed1987

Chronic active hepatitis with histological features of primary biliary cirrhosis.

A 51-year-old woman was evaluated because of Raynaud's phenomenon, Sjögren's syndrome, and general malaise. There was neither skin itching nor jaundice. Endoscopic retrograde cholangiopancreatography showed a normal extrahepatic as well as intrahepatic biliary tree. Serum GOT and GPT fluctuated with episodes of marked increases. The alkaline phosphatase was slightly increased and total cholesterol was normal. There were marked increases of IgG and IgM. AMA was positive at a titer of 1:320, which was measured by an indirect immunofluorescence method. PBC-specific AMA (anti-M2) was positive, but mixed-form AMA (anti-M4) negative. An LE-cell test, ASMA, ANA, and anti-DNA antibody were all positive on several repeated tests. A wedge liver biopsy tissue showed mixed features of PBC and CAH. A diagnosis of CAH was made on the basis of the clinical, serological, and morphologic findings. The patient responded well to prednisolone treatment with prominent improvement of her symptoms and liver function tests. Subsequently, AMA fell to undetectable levels by indirect immunofluorescence method.

Antibodies↗
PubMed1987

Biological significance of AFP-positive cells in rat livers with hyperplastic nodules induced by 3'-Me-DAB; combined immunocytochemical and radioautographical studies.

We investigated alpha-fetoprotein (AFP)-positive cells in 3'-Me-DAB hepatocarcinogenesis. In the early stage of 3'-Me-DAB hepatocarcinogenesis immunoreaction of AFP was detected in proliferating cholangiolar "oval" cells and in the late stage, AFP-positive cells, differing from oval cells, were detected in clusters in rat liver with hyperplastic nodules. The clusters of AFP-positive cells were morphologically classified into two different types of foci and one type of nodule. The combined techniques of immunocytochemistry and ratioautography revealed that AFP-positive foci and nodule had more 3H-thymidine labeling index than did areas without AFP-positive cells in liver with hyperplastic nodules; also one type of AFP-positive foci had a higher labeling index than the other type and in AFP-positive nodules there was active cell proliferation; but AFP-positive foci or nodules had less 3H-thymidine labeling than AFP-positive hepatoma cells. These findings suggested that AFP-positive foci and nodule had different biological significance in development of hepatocellular carcinoma and that AFP-positive foci with higher labeling index and AFP-positive nodule should be surveyed as preneoplastic population.

Animals↗