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Biomedical subjects

S Yoshimatsu

Publications and source records attributed to S Yoshimatsu.

78 records · Page 5Linked to original sources
PubMedDate not supplied

Combined effects of ultrasound and ionizing radiation on lymphocyte chromosomes.

The effects of ionizing radiation and ultrasound upon the induction of chromosomal-type aberrations and sister chromatid exchanges were investigated. No statistically significant increase in the frequencies of dicentric and ring chromosomes or sister chromatid exchanges was discovered after ultrasound exposure alone at the diagnostic level. Nor could elevated frequencies of these phenomena be found following exposure to ultrasound before or after ionizing radiation, compared with those resulting from an equivalent dose of ionizing radiation alone. However, simultaneous exposure to ultrasound and ionizing radiation seemed to induce a slight enhancement of sister chromatid exchanges, although no significant change was noted in the yields of dicentric and ring chromosomes.

Abnormalities, Radiation-Induced↗
PubMedDate not supplied

Correlation of 99mTc-GSA hepatic scintigraphy with liver biopsies in patients with chronic active hepatitis type C.

99mTc-DTPA-galactosyl human serum albumin (99mTc-GSA) liver scintigraphy was performed in 230 patients with chronic active hepatitis type C, and its quantitative indices were compared with histological findings. 99mTc-GSA findings correlated well with four indices of the histology activity index (HAI), especially with the fibrosis score. Ninety patients were given interferon treatments, and 99mTc-GSA findings were compared with the results of the treatments. We classified the effects of interferon treatment into three groups according to clinical outcome: group 1: good effect (HCV-RNA negative, n = 34), group 2: moderate effect (HCV-RNA positive, but the value of GPT was normal for six months after the end of treatment, n = 19) and group 3: no effect (n = 37). Quantitative indices of 99mTc-GSA showed significant differences between groups. Follow-up study with 99mTc-GSA scintigrams was obtained in eight patients. The results of 99mTc-GSA improved in three patients in group 1 and deteriorated in five patients in group 3. There is a possibility that 99mTc-GSA scintigraphy can be used to predict the clinical outcome of chronic active hepatitis type C after interferon treatment.

Adult↗
PubMedDate not supplied

Percutaneous microwave coagulation therapy: an experimental study.

PURPOSE: Microwave coagulation therapy (MCT) is a surgical alternative for inoperable hepatocellular carcinomas (HCCs). We have recently developed a percutaneous method for using MCT under ultrasound guidance. The purpose of this study was to investigate the feasibility of percutaneous MCT (PMCT) in an animal model and correlate the ultrasound findings with histological results. MATERIALS AND METHODS: Microwaves were administered for 30, 45, 60 and 90 seconds to 12 cadaveric porcine livers in vivo one hour after sacrificing them, to determine the most suitable coagulation time for the percutaneous method. The cadaveric livers were then subjected to histologic evaluation. The temperature around the electrode was measured in both cadaveric and living livers during PMCT. Ultrasound-guided MCT was also performed in nine rabbits. The histological findings after PMCT were evaluated in the cadaveric and living livers, and the areas of coagulation necrosis were correlated with the ultrasound findings. RESULTS: After microwave emission, coagulation necrosis of a spindle shape occurred primarily from the base of the electrode. The maximum area of coagulation was obtained at 60 seconds. The maximum temperature of cadaveric liver under PMCT was 95 degrees at 3 mm from the electrode; that of living liver was 85.1 degrees at 5 mm. Ultrasound revealed hyperechoic areas after PMCT in both cadaveric and living livers. On microscopy, parenchymal necrosis of the liver was observed only in living livers one month after MCT. Hyperechoic areas measured with ultrasound were significantly larger than the actual necrotic areas (p < 0.01), probably due to air bubbles which developed within the tissue. CONCLUSIONS: PMCT completely coagulated the liver tissue around the electrode. These preliminary results indicate that PMCT should be an effective treatment for hepatic neoplasms. In terms of clinical application, the hyperechoic areas observed during PMCT appear to be considerably larger than the areas actually treated.

Animals↗
PubMedDate not supplied

Small cell carcinoma of the stomach: a case report.

A case of a gastric small cell carcinoma discovered incidentally by screening ultrasonography is presented. Ultrasonography demonstrated a subcardial metastatic lymph node and multiple hepatic metastatic lesions. Upper GI series and gastroendoscopy revealed a large ulcerated tumor in the cardia of the stomach, and a Borrmann type II tumor, 4 x 2.5 cm, was found in the resected stomach. We describe the radiological findings of the upper GI series, ultrasonography, CT, and gastroendoscopy, and review the literature.

Aged↗