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M Tsuchitani

Publications and source records attributed to M Tsuchitani.

50 records · Page 3Linked to original sources
PubMed1987

Relationship between cellular morphology and immunocytological findings of spontaneous pituitary tumours in the aged rat.

A total of 339 spontaneous pituitary tumours from 284 aged rats were studied by light microscopy. Based on the cellular morphology in preparations stained by haematoxylin and eosin, tumour cells were classified into 4 types: granular; agranular small; agranular large polygonal; and agranular large slender cells. Eight tumours consisted of mixed neoplastic masses of 2 types of cells. A total of 85 cases representative for each tumour type was used for special staining and immunocytochemistry. All tumours of the granular cell type and some tumours of the agranular large polygonal cell type had granules which stained red by azocarmine and were positive for prolactin. All agranular small cell type tumours were also positive for prolactin and agranular slender cell type tumours were positive for adrenocorticotropic hormone. Only tumours of the agranular large polygonal cell type gave an indefinite or negative reaction for all the various pituitary hormones. These results indicate a relatively good correlation between the cellular morphology and the immunocytochemistry of spontaneous pituitary tumours in aged rats.

Adrenocorticotropic Hormone↗
PubMed1985

Microfilarial granulomas in the spleens of wild-caught cynomolgus monkeys (Macaca fascicularis).

Splenic nodules from 38 cynomolgus monkeys (Macaca fascicularis) which were captured in Malaysia and Indonesia were studied histologically. The lesions were characterized by well-circumscribed focal fibrosis, accumulation of eosinophils and histiocytes, hemorrhage or hemosiderosis, and loss of normal splenic architecture. Small arteries in the lesion frequently had intimal thickening and narrowing of the lumen in addition to the presence of microfilariae. Microfilariae were also seen in the extravascular area of the lesion, and were occasionally engulfed by multinucleated giant cells. The splenic lesion was thought to have been initiated by incomplete infarction caused by intimal thickening and microfilarial occupation of the small arteries.

Animals↗
PubMed1985

A new diabetic strain of rat (WBN/Kob).

A new, spontaneously occurring diabetic syndrome has been observed in the aged males of an inbred strain of Wistar rats, WBN/Kob. The main clinical sign, glycosuria, was first detected at about 60 weeks of age, and thereafter some animals developed hyperlipidaemia and gradual emaciation. Prior to the onset of glucosuria, male rats showed impaired glucose tolerance after a glucose load at 21 weeks of age. The histopathologic lesions of the pancreas in the diabetic males consisted of multifocal fibrosis, decreased in number and size of islets and atrophy of exocrine tissue. Multifocal inflammatory foci of varying stages were the main pancreatic lesion in prediabetic male rats. This inflammatory change was detected even in 12-week-old rats and tended to occur around the islets. Therefore focal fibrosis and the decrease in the number and size of islets were considered to result from post-inflammatory scarring. The maturity-onset of this syndrome and the impaired glucose tolerance in younger animals suggested that diabetes mellitus of this rat strain is insulin-independent type II. However, the histological lesions of the pancreas were somewhat different from previous reports of both type I and II diabetes mellitus in man and animals.

Animals↗
PubMed1983

The morphogenesis of a papillomatous gastric polyp in the crab-eating monkey (Macaca fascicularis).

The histopathology of gastric papillomas in 17 crab-eating monkeys from Indonesia and Malaysia was investigated. The changes in the affected mucosa consisted of papillomatous proliferation with accidental heterotopia, desquamation or necrosis of the epithelium associated with eggs or adults of the small nematode Nochtia nochti, inflammatory cell infiltration and haemorrhage or oedema and fibrosis. The primary pathogenic effect of this parasite was due to its irritant action on the gastric mucosa. Hyper-regeneration, with a downward shift of the proliferating zone in the gastric gland and an inflammatory process, appeared to play a significant role in the morphogenesis of this lesion. It is concluded that the gastric papilloma associated with Nochtia nochti in the monkey is a parasitic inflammatory polyp.

Animals↗
PubMed1983

Naturally occurring Tyzzer's disease in a clean mouse colony: high mortality with coincidental cardiac lesions.

Light and electron microscopic examinations were performed on tissues from 12 young mice which were affected by naturally-occurring Tyzzer's disease. Eight of the 12 mice had cardiac lesions which have not previously been reported in mice and which caused a high mortality. The cardiac lesions were detected in mice which had severe and advanced intestinal lesions which penetrated the deeper mucosa and muscular layer with active regeneration of the mucosal epithelium. Periodical serological tests to monitor the bacterial and viral status of this colony showed that it was free of other agents of murine disease such as mouse hepatitis virus, Corynebacterium kutscheri and Salmonella spp. until the onset of Tyzzer's disease and that no mixed infection occurred at the onset. It is considered that an advanced intestinal lesion is essential for the formation of cardiac lesions in Tyzzer's disease in mice.

Animals↗
PubMedDate not supplied

Cadmium-induced dental lesions in ovariectomized rats.

The effects of cadmium chloride on both incisor and molar teeth of ovariectomized female rats were studied histopathologically. The rats were injected intravenously with the compound at doses of 1.0 and 2.0 mg/kg, 5 days/wk. Six rats per group were sacrificed at 4, 8, and 13 wk. Discoloration of the incisors was observed in the rats of the 2.0-mg/kg group from 8 wk. Histopathologic examination of the incisor demonstrated decreased iron-containing pigment in ameloblasts and destruction of the enamel organ. These changes were accompanied with accumulation of cadmium and loss of iron in the teeth. Necrosis of the dental pulp occurred from the coronal end of both the incisor and molar teeth extended to the apical, deep portion of the teeth. The dental pulp of the molar teeth, which is shorter than that of the incisor, was mildly affected by cadmium intoxication. These findings suggested that intradental ischemia due to cadmium toxicity may have contributed to the development of the pulpal necrosis.

Animals↗
PubMedDate not supplied

Case report: spontaneous hemangiosarcoma in the pancreas of a Fischer rat.

Spontaneous hemangioma or hemangiosarcoma is sometimes found in the viscera and soft tissue of rats and mice. However, there is no report of the tumor occurring in the pancreas of rats. We report a pancreatic hemangiosarcoma in a 109-wk-old, male Fischer 344 rat, which was used in the control group of a carcinogenicity study. The tumor destroyed and compressed the normal pancreatic tissue and displayed a high density in terms of the numerous capillaries and strands of endothelial tumor cells. A reticulin stain revealed a dense network formation. The frequency of proliferating cell nuclear antigen-positive staining showed active proliferation of the tumor cells. Immunohistochemically, some of the tumor cells stained positive with factor VIII-related antigen, and ultrastructurally, Weibel-Palade bodies were rarely observed in the cytoplasm of the tumor cell. From these findings, the tumor was diagnosed as a hemangiosarcoma that occurred naturally in the pancreas.

Animals↗