Biomedical subjects

S Takase

Publications and source records attributed to S Takase.

348 records · Page 20Linked to original sources

PubMedDate not supplied

Effects of ethanol on the secretion of hepatic secretory protein in rat alcoholic liver injury.

It has been pointed out that one of the pathogenetic causes of alcoholic liver injury is the hepatocytic accumulation of exportable proteins due to a decrease in hepatic microtubules caused by acetaldehyde. To confirm and extend this secretory protein accumulation in the hepatocytes, the effects of alcohol treatment on the intracellular transport of secretory protein in the hepatocyte was studied using radioisotope-labeled leucine and fucose. Acute ethanol administration to rats did not show any effects on intrahepatocytic transport and secretion of transferrin. In alcohol pyrazole hepatitis rats, the secretion of transferrin labeled with both radioactive leucine and fucose into the serum was significantly delayed. Delaying in the secretion of fucose-labeled transferrin was more prominent than in leucine-labeled transferrin. This secretory inhibition was accompanied by a corresponding increase in the hepatic retention of both leucine- and fucose-labeled transferrin. At the time of the maximum inhibition of secretion, radioisotope labeled transferrin mainly retained in the Golgi apparatus. These results indicated that movement of secretory proteins along the secretory pathway impaired in alcoholic liver injury and that accumulation of the secretory proteins might play an important role in the development of alcoholic liver injury.

Animals↗

PubMedDate not supplied

Effects of ethanol and its metabolites on collagen synthesis by cultured rat liver cells.

The effects of ethanol and its metabolites on collagen synthesis in cultured rat Ito cells and hepatocytes were studied. In cultured Ito cells, collagen synthetic ability reached peak values after incubation for 24 h and after 8 h in cultured hepatocytes. The distribution patterns of 14C-activity in each collagen fraction were quite different between the two cell types. About 80% of the activity was found in the degraded collagen fraction in the cultured hepatocytes, indicating a rapid turn-over of collagen protein in this cell type. In the Ito cells, the activity in the intact collagen was about 50%. Ethanol and its metabolites added to the incubation medium did not stimulate collagen synthesis in either cell type; rather, they inhibited it. Collagen metabolism in the cells to which ethanol or its metabolites had been added was slower than in the control medium. These results indicate that the pathogenesis of alcoholic liver fibrosis is not simple and that interaction or modulation of cell function in different types of cells should be considered when examining the mechanisms of fibrogenesis in alcoholic liver fibrosis.

Acetaldehyde↗

PubMedDate not supplied

Collagen synthesis by cultured rat liver cells isolated from chronically alcohol-treated rats.

Incorporation rates of 14C-proline into collagen hydroxyproline in cultured Ito cells and hepatocytes isolated from chronically alcohol-treated rats were studied in order to clarify the role of Ito cells in the development of alcoholic liver fibrosis pathogenesis. In the cultured Ito cells isolated from alcohol-treated rats, prolyl hydroxylase activity significantly increased. Total collagen synthesis tended to increase in the alcohol group, and the increase in intracellular intact collagen was statistically significant. More than half of the 14C-radioactivity in intact collagen in cultured Ito cells from control rats was found in collagen other than types I and III collagen (mainly type IV collagen). In Ito cells from alcohol-treated rats, synthesis of collagen other than type I and III significantly increased and type I collagen synthesis tended to be decreased. No significant difference was found in collagen synthesis between the cultured hepatocytes from alcoholic and control rats. These results suggest that chronic alcohol consumption stimulates collagen synthesis in Ito cells, especially type IV collagen. This stimulation of Ito cells may play a role in the development of alcoholic liver fibrosis.

Animals↗

PubMedDate not supplied

Comparison between ballooned hepatocytes occurring in human alcoholic and nonalcoholic liver diseases.

To establish clearly what the pathogenetic differences are in the hepatocytic ballooning between human alcoholic and nonalcoholic liver diseases, hepatic microtubules were examined by morphometric and biochemical methods, and staining of transferrin was carried out on liver sections immunohistochemically. Microheterogeneity of serum transferrin was also detected by immunofixation after isoelectric focusing. Hepatic microtubules were significantly decreased in alcoholic liver disease, and transferrin was clearly stained in the ballooned hepatocytes of alcoholic liver disease but not in nonalcoholic liver disease. The degree to which transferrin was stained was related to hepatic microtubular contents and also related to the appearance of the microheterogeneity of serum transferrin in alcoholic liver disease. These findings indicate that ballooning of hepatocytes in alcoholic liver disease, but not in nonalcoholic liver disease, is caused by the accumulation of exportable proteins due to impairment of microtubular polymerization. This accumulation might be related to the inhibition of glycosylation and secretion of glycoproteins by the impairment of microtubular functions. From these results, it was determined that staining of transferrin in the liver may be useful for differentiation of the etiology of liver diseases.

Biopsy, Needle↗

PubMedDate not supplied

Painless myocardial infarction in identical diabetic twins.

A pair of 37-year-old identical twins with diabetes mellitus are described. One of the brothers was admitted for heart failure without pain, and autonomic neuropathy was found. The clinical diagnosis was inferior myocardial infarction with anteroseptal healed myocardial infarction. Cardiac catheterization revealed triple coronary vessel involvement. The diagnosis was confirmed at autopsy after sudden death. The other brother was also examined by cardiac catheterization, which revealed total right coronary occlusion and hypokinesis of the wall. There had been no previous pain nor upper body discomfort until that time in either twin. Thus, genetic factors should possibly be considered in the genesis of asymptomatic or silent myocardial infarction.

Adult↗

PubMedDate not supplied

[External valvuloplasty under preoperative angioscopic control].

Intraoperative angioscopy was applied to evaluate the venous valvular incompetence and perform external valvuloplasty in case of venous reflux. Sixty-seven limbs, 43 cases of primary varicose veins were examined using intraoperative angioscopy and the angioscopic findings of the incompetent venous valves were classified into three types as follows: valves with elongated and atrophic cusps 43 (50%)--type I, values with expanded and depressed commissures 36 (42%)--type II, and valves with perforated cusps or other changes 7 (8%)--type III, according to the angioscopie findings, external valvuloplasty was done in 31 subterminal valves of the long saphenous veins and 7 highest valves of the superficial femoral vein. Our external valvuloplasty consisted of two techniques. The first was the total plication technique for valvular annulus by a running suture of prolene and the second was by the venocuff sleeve of the autogenetic femorofascial band. The degree of plication was decided by angioscopic observation. Postoperative observation periods were from 2 to 28 months. There was no recurrence of varicose veins or prominent venous reflux. The application of intraoperative angioscopy is therefore useful for the choosing appropriate surgical procedures and for the evaluation of venous valvuloplasty.

Adult↗