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Biomedical subjects

M Itabashi

Publications and source records attributed to M Itabashi.

102 records · Page 6Linked to original sources
PubMed1975

Experimental porphyria induced by 3-(2,4,6-trimethylphenyl)-thioethyl)-4 methylsydnone.

Administration of 3-[2-(2,4,6-trimethylphenyl)-thioethyl]-4-methylsydnone (TTMS) induces hepatic porphyria in rats, mice and dogs. The protoporphyrin pigment in livers of rats and mice is found mainly in bile ducts and leads to bile duct proliferation and portal inflammation. Dog livers contain protoporphyrin predominantly in bile canaliculi. The birefringence of the pigment appears to be associated with bilamellar components within the pigment. The markedly depressed catalase activity in livers of rats does not increase after clofibrate administration. The catalase activity of mouse liver is depressed slightly and responds to clofibrate treatment.

Alcohol Oxidoreductases↗
PubMed1975

Response of microbodies in Morris hepatoma 9618A to clofibrate.

Regulation of the formation of microbodies in Morris hepatoma 9618A was studied by examination of the response of the organelles to clofibrate. The fine structures of microbodies in the hepatoma cells closely resembled those in hepatocytes of normal adult rats. In clofibrate-treated rats, the tumor cells showed a slight increase in the size of microbodies and in catalase activity; however, the tumor microbodies did not increase in number. In contrast, in adult clofibrate-treated rats and rats on the day of birth whose mothers received clofibrate during the gestation period, the hepatocytes showed microbodies that were greater in both number and size, and the catalase activity in the liver was definitely elevated.

Animals↗
PubMed1975

Peroxisomes in liver tumors of rats induced by 3'-methyl-4-(dimethylamino)azobenzene.

Peroxisomes were present in trabecular carcinoma and adenocarcinoma induced by 3-methyl-4-(dimethylamino)azobenzene in the liver of rats. Peroxisomes in well-differentiated trabecular carcinoma (type I) resembled more or less those in hepatocytes in their electron microscopic features, but were considerably small in number. Poorly differentiated trabecular carcinoma (type II) and adenocarcinoma contained peroxisomes in far smaller number than in the well-differentiated trabecular carcinoma, or frequently showed no peroxisomes. Peroxisomes in poorly differentiated trabecular carcinoma and adenocarcinoma were small in size, contained scanty matrix in general, and almost lacked crystalloid nucleoids; however, they were easily identified by electron microscopic cytochemistry of catalase. Catalase activity of these tumors was significantly lower than in the liver tissues. These tumors did not respond to ethyl chlorophenxyisobutyrate either by proliferation of peroxisomes or by elevation of catalase activity. It is thus suggested that the cellular mechanisms for regulating the formation of peroxisomes and synthesis of the enzyme involved are impaired in the tumor cells.

Adenocarcinoma↗
PubMedDate not supplied

Antibody to the receptor for polymerized human serum albumin in acute and persistent infection with hepatitis B virus.

The antibody against the receptor for polymerized human serum albumin was determined by radioimmunoassay. The method involved the inhibition by the test serum, absorbed with HBsAg particles without the receptor, on the binding of polymerized human serum albumin to HBsAg particles with the receptor fixed on a solid support. The amount of polymerized human serum albumin captured by the receptor on HBsAg was then determined by the radiolabeled monoclonal antibody directed to an epitope specific for polymerized human serum albumin. In acute infection, the antibody to the receptor for polymerized human serum albumin appeared in the early recovery phase while HBs antigenemia and elevated transaminase levels were still present, preceding the antibody to HBsAg (anti-HBs). The antibody was detected in 4 (1%) of 358 sera from asymptomatic carriers of HBsAg containing antibody to HBeAg, and in none of 67 sera containing HBeAg. Although the antibody was found in as many as 111 (74%) of 150 sera from blood donors who had presumably acquired anti-HBs after natural infection, it was not detected in any sera from 77 recipients of hepatitis B vaccine who had seroconverted for anti-HBs. On the basis of these observations, the determination of antibody to the receptor for polymerized human serum albumin helps in further understanding the immunity to hepatitis B virus.

Acute Disease↗
PubMedDate not supplied

Comparison between pancreatoduodenectomy and hepatopancreatoduodenectomy for bile duct cancer.

BACKGROUND/AIMS: Pancreatoduodenectomy has been accepted as a standard operative procedure for distal bile duct cancer with low operative mortality. However, hepatopancreatoduodenectomy has not been accepted as a standard treatment modality for diffuse bile duct cancer. METHODOLOGY: From December 12, 1992 to December 15, 2000, 37 patients with the diagnosis of extrahepatic bile duct adenocarcinoma (cholangiocarcinoma) underwent pancreatoduodenectomy or hepatopancreatoduodenectomy, at the department of surgery, Ibaraki Prefectural Central Hospital and the Cancer Center. The differences in indications and results of both operative procedures were investigated retrospectively. RESULTS: Thirty-day operative mortality was 0% after either pancreatoduodenectomy or hepatopancreatoduodenectomy. One- to 5-year cumulative survival rates for the 24 patients after pancreatoduodenectomy were 76.3%, 41.5%, 41.5%, 41.5%, 41.5%, respectively. One- to 4-year cumulative survival rates for the 13 patients after hepatopancreatoduodenectomy were 48.0%, 32.0%, 32.0%, 16.0%, respectively. There were no statistically significant differences between cumulative survival rates after pancreatoduodenectomy and hepatopancreatoduodenectomy either in all the patients or in patients with UICC stage IV. CONCLUSIONS: Hepatopancreatoduodenectomy should be tried for patients with diffuse bile duct cancer, because only hepatopancreatoduodenectomy has the possibility of a cure at this time.

Aged↗
PubMedDate not supplied

Extended intestinal metaplasia. A survey of 1392 gastrectomies from dwellers of the Pacific basin.

BACKGROUND: To assess the extent of gastric intestinal metaplasia (IM) in gastrectomy specimens in populations of the Pacific basin having different incidence of gastric carcinoma. MATERIALS AND METHODS: One thousand three hundred and nine-two gastrectomies were investigated: 1088 had a gastric carcinoma and 304 miscellaneous gastric diseases. Twenty-one thousand three hundred and fourteen histological sections were reviewed under low-power (4X). IM was either spotty (SIM) or extended (EIM= encompassing one or more entire low-power fields/section). Widespread IM (WIM) was regarded as EIM if present in > or =5 histological sections. RESULTS AND CONCLUSION: The percent of gastrectomies harboring a carcinoma increased significantly with increasing age more notably in those with diffuse carcinomas (DC) than in those with intestinal carcinomas (IC). The percent of gastrectomies with EIM was significantly higher in specimens with IC than with DC, particularly among elderly patients, and in specimens from countries with a high cancer incidence. The percent of gastrectomies with WIM was higher in specimens having IC than in those having DC. Migration per se did not influence the frequency of specimens with EIM in elderly Japanese patients: Japanese migrants to Hawaii had a similarly high frequency of EIM as those dwelling in Japan. Japanese patients with a gastric carcinoma showed atypical mitoses in areas with EIM far from the tumor, suggesting that cellular mutation(s) play a role in the evolution of EIM towards gastric dysplasia and carcinoma in that ethnic group. The drawback of gastric biopsies in assessing the extent of gastric intestinal metaplasia and, thereby, estimating possible cancer risk in long-term studies has been stressed.

Age Factors↗
PubMedDate not supplied

Comparative studies on the histogenesis of squamous carcinoma of esophagus in mice and in human subjects.

Histological changes occurring in the esophageal mucosa of 110 C57b1 mice, after protracted topical treatment with diethylnitrosamine, were compared to those present in human esophagus in three patients operated for early esophageal cancer. Both in mice and in human material, the histological changes were classified into slight, moderate or severe dysplasia, carcinoma in situ, questionable invasive carcinoma and invasive carcinoma. Starting from moderate dysplasia, the epithelial-stroma border became irregular with bud formation bulging into the stroma. The findings strongly suggest an association between the degree of cellular atypia, the formation of epithelial buds, and progression towards invasive carcinoma.

Animals↗