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T Ishiwata

Publications and source records attributed to T Ishiwata.

69 records · Page 4Linked to original sources
PubMed1994

Fibronectin biosynthesis in endothelial regeneration after intimal injury.

In this experiment, we sought to identify the major fibronectin (FN) synthesizing cells, the source of FN production, and the role of FN in intimal regeneration. In rats in which vascular endothelial denudation had been induced, serial morphologic changes after intimal injury were studied by light and electron microscopic examination using immunohistochemical techniques and in situ hybridization. At 2 weeks after intimal injury, regenerated endothelial cells had pleomorphic cytoplasm and loose cellular junctions. Immunohistochemically, factor VIII-related antigen was localized in the regenerated endothelial cells, and immunoreaction products of FN were increased in the thickened neointima. Ultrastructurally, FN was localized in the proliferated endoplasmic reticulum of regenerated endothelial cells in the intima, while the alpha 5 subunit of alpha 5 beta 1 integrin, one of the fibronectin receptors, was localized in the plasma membrane and increased endoplasmic reticulum of regenerated endothelial cells. FN mRNA was localized in a large number of regenerated endothelial cells (87.2 and 89.8%) by in situ hybridization at 2 and 4 weeks after intimal injury. These findings indicate that FN may mainly contribute to endothelial cell functions such as spreading and adhesion in the regenerative stage.

Animals↗
PubMed1994

Process of basement membrane re-formation after intimal denudation.

During re-endothelialization after intimal denudation induced by balloon catheter in the rat aorta, re-formation of the basement membrane (BM) was examined in samples taken 15 min, 3, 7, 14, 21 and 28 days after the balloon-induced injury. Although the luminal surface of the aortic wall was covered by round-shaped regenerating endothelial cells (ECs) by 7 days after intimal denudation, no continuous BM structure was detectable until 21 days. Periodic acid-thiosemicarbazide gelatin-methenamine silver (PATSC-GMS) staining for electron microscopy and immunostaining of type IV collagen and laminin demonstrated the accumulation of BM components underneath the regenerating ECs after 14 days. The expression of type IV collagen mRNA was revealed in regenerating ECs by in situ hybridization. A continuous BM structure first appeared 21 days after intimal denudation and was almost complete by 28 days. Simultaneously, the regenerating ECs flattened and attached more closely to the BM than in earlier phases. In conclusion, we consider that the regenerating ECs produce the BM components and suggest that reorganization of the newly formed BM is important in the process of differentiation of regenerating ECs.

Animals↗
PubMed1994

[Report of two cases with idiopathic true exfoliation of the lens capsule--histopathological and electron microscopical study].

True exfoliation is a delamination of the superficial or all layers of the anterior lens capsule, appearing as a transparent membrane in the anterior chamber. It is a rare occurrence and most of the reported cases have been associated with histories of exposure to excessive heat, ocular trauma, or intraocular inflammation. We report two cases of idiopathic true exfoliation without any contributory history. In one case, the lens was surgically removed intracapsularly, and served for histological study and scanning and transmission electron microscopy. The anterior fourth of the capsule was delaminated. Underlying epithelial cells showed nonspecific senile changes.

Aged↗
PubMed1991

[An autopsy case of cardiomyopathy combined with nephrotic syndrome and pulmonary cytomegalic inclusion disease].

A 63-year-old male complained of palpitation and dyspnea. ECG showed paroxysmal supraventricular tachycardia. Echocardiogram revealed asymmetrical thickening of the cardiac septum, and by other clinico-pathological observations, nephrotic syndrome and colon adenoma were detected. For these diseases, steroid therapy and operation were performed, respectively. Ten months later, chest X-ray revealed diffuse abnormal shadow in the bilateral lung fields, and the patient expired due to respiratory distress syndrome. The patient's heart weighted 300g and showed extensive myofibril disarray in bilateral ventricles involving the septal region of the heart. Degeneration and atrophy of the atrioventricular node was seen. In the lungs, organizing pneumonia, old pleuritis, diffuse septal fibrosis and cytomegalovirus infection were demonstrated in the alveolar walls. Kidneys showed slightly sclelotic changes in glomeruli and edema-fibrosis in the interstitium. In this rare case, hypertrophic cardiomyopathy was combined with nephrotic syndrome due to glomerular change, and colon adenoma. The patient died of cytomegalovirus infection in the lungs. The histogenesis of myofibril disarray was discussed in these diseases.

Cardiomyopathy, Hypertrophic↗
PubMed1990

[A hepatocellular carcinoma showing sarcomatous features and an extensive metastasis].

A 47-year-old female was admitted for a right hypochondrial pain and was diagnosed as having a hepatic tumor with a cystic lesion. After a right and a caudal lobectomy, she died of hepatic failure due to a tumoral recurrence. At autopsy, a cystic tumoral nodule, 15 x 7 cm in size, and numerous other nodules were revealed in the liver. Metastases were seen in both lungs, the left kidney, the colon, the mesenterium, the peritoneum, the diaphragm, and the para-pancreatic lymph nodes. The hepatic tumors consisted of four types of tumor cells: spindle, round, mixed (spindle and round cells), and cells with pseudoalveolar features. All tumor cells showed a positive immunohistochemical reaction to polyclonal keratin, low molecular monoclonal keratin, alpha 1 anti-trypsin, vimentin and to actin in their cytoplasms. This is considered a very rare case.

Actins↗
PubMed1989

[In vivo biomicroscopy of the human lens].

The human lens was observed in vivo by a specular microscope and specially designed cone contact lens. The lens fibers of central part of the anterior cortex were photographed and their widths measured in 16 healthy normal males in the third and fourth decades of life. The average width of the fibers was 12.35 +/- 1.17 microns and 12.36 +/- 0.80 microns. There was no statistically significant difference in average width between the two groups when the objectives were divided by their age in twenties and thirties.

Adult↗
PubMed1983

Oncocytic adenocarcinoma of the ovary.

A case of ovarian adenocarcinoma mainly composed of oncocytes was studied by light and electron microscopy. Oncocytes, characterized by granular and eosinophilic cytoplasm by light microscopy possessed numerous mitochondria at the ultrastructural level. These oncocytes were classified into two types: typical and condensed oncocytes. Typical oncocytes seemed to be active, whereas condensed oncocytes were thought to be involved in a degenerative process. The two types of cells showed a close similarity to oncocytes in other organs (e.g., thyroid, parathyroid and salivary glands). This appears to be the first report of an ovarian oncocytic tumor.

Adenocarcinoma↗
PubMedDate not supplied

Differential expression of hepatocyte growth factor and its receptor (c-Met) in a rat artificial anus model.

Hepatocyte growth factor is a multifunctional polypeptide that has been implicated in cancer growth, tissue development and wound repair. It is mainly synthesized in mesenchymal cells and acts on epithelial cells, where its actions are dependent on binding to a specific cell-surface hepatocyte growth factor receptor (c-Met). In an artificial anus, two different types of epithelial cells (ductal cells of the colon and squamous cells of the skin) intermingle with each other. In the present study, we examined the localization of hepatocyte growth factor and c-Met during the process of repair in a rat artificial anus model, and attempted to clarify the cell types that express hepatocyte growth factor or c-Met messenger RNA by in situ hybridization. Western blot analysis revealed abundant localization of the mature form of hepatocyte growth factor in artificial anal tissues. Moderate hepatocyte growth factor immunoreactivity was noted in regenerated squamous cells in the skin and colonic ductal cells, and strong expression in macrophages and fibroblasts. Moderate c-Met immunoreactivity was present in regenerated epithelial cells in the skin and colon. Throughout the repair process, hepatocyte growth factor and c-Met immunoreactivities were more prominently localized in the squamous cells of the skin than in colonic ductal cells. Competitive reverse transcription-polymerase chain reaction analysis revealed that hepatocyte growth factor mRNA was maximal on day 14 after the operation; however, c-Met mRNA expression had two peaks, on day 1 and day 7. Hepatocyte growth factor mRNA was expressed more in the stromal fibroblasts, macrophages and endothelial cells, and c-Met mRNA was predominant in regenerated squamous cells of the skin. These findings suggest the possibility that hepatocyte growth factor may act in a paracrine manner to mainly enhance the growth of squamous cells of the skin and to a lesser extent the ductal cells of the colon in the artificial anus.

Animals↗
PubMedDate not supplied

Increased cyclin D1 in human pancreatic cancer is associated with decreased postoperative survival.

Cyclin D 1 belongs to a family of protein kinases that have been implicated in cell cycle regulation. In the present study we characterized cyclin D1 expression in 6 cultured human pancreatic cancer cell lines and in normal and cancerous human pancreatic tissues. A 4.4-kb cyclin D1 mRNA transcript was present in all cell lines and in all pancreatic tissues. Cyclin D1 mRNA levels were 2.1-fold higher in the pancreatic cancers than in normal pancreatic tissues (p < 0.0002). Cancer patients with lower cyclin D1 levels (n=16) had a median survival of 15.5 months whereas patients with higher levels (n=16) had a median survival of 6.5 months (p < 0.007). These data indicate that cyclin D1 expression may serve as a predictor of postoperative survival in pancreatic cancer patients, and raise the possibility that treatment modalities blocking cyclin D1 activity may have a future role in the therapy of these patients.

Adult↗
PubMedDate not supplied

Tumor angiogenesis as an independent prognostic indicator in human papillary thyroid carcinoma.

Angiogenesis has been determined to play a very important role in either the growth of solid tumors or their recurrence in distant organs. Microvessels stained immunohistochemically for the factor VIII-related antigen were counted in one hundred patients with papillary thyroid carcinoma in order to clarify the association of tumor angiogenesis with the prognosis of the disease. The mean microvessel count (MVC) was significantly higher in tumors with distant recurrence than those without recurrence. Disease-free survival of patients with a high MVC (>/= 23) was significantly worse than that of patients with a low MVC (</= 22), as well as the overall survival. In multivariate analysis, the MVC was most strongly correlated with disease-free survival, and was independent of other prognostic factors. In conclusion, the MVC is a potent prognostic indicator in papillary thyroid carcinoma.

Adolescent↗
PubMedDate not supplied

Effect of general anesthesia on the abnormal immune response in patients with rheumatoid arthritis.

OBJECTIVE: To evaluate the influence of mental stress on the neuroendocrine-immune system in patients with rheumatoid arthritis (RA). METHODS: Twenty-four patients with RA and 10 patients with osteoarthritis (OA) who underwent total knee or hip arthroplasty under general anesthesia were enrolled in this study. The blood levels of interleukin-6 (IL-6), IL-1 receptor antagonist (IL-1Ra), tumor necrosis factor-alpha (TNF-alpha), soluble TNF receptors (TNF-Rs) and other substances related to stress were measured just before administering anesthesia on the day of the operation when the patients lay on the operating table and roughly 30 min later when the patients were under general anesthesia without mental stress. These values were compared with those at the same time on the day before the operation, which were considered as controls. RESULTS: In patients with RA under general anesthesia, the levels of IL-6, TNF-alpha, and TNF-R1 and TNF-R2 in the peripheral blood were significantly decreased compared with the levels before anesthesia (p < 0.01). Before anesthesia the levels of IL-1Ra in the peripheral blood were significantly higher, and the level of IL-1Ra was enhanced after the administration of general anesthesia, when compared with the level on the day before the operation (p < 0.01). Such changes were not apparent in patients with OA. CONCLUSION: In patients with RA, excessive mental stress should be eliminated to modify the interaction between the stress-immune system and stress-endocrine system as a method to better control disease activity.

Aged↗