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Biomedical subjects

T Shimura

Publications and source records attributed to T Shimura.

At least 163 records · Page 9Linked to original sources
PubMed1985

[Pathology of intracerebral hemorrhage in ruptured aneurysms of the posterior communicating artery at its origin from the internal carotid artery].

There were thirty-two autopsied cases of ruptured aneurysms at the junction of the internal carotid and posterior communicating arteries in the file of Montefiore Medical Center from 1948 to 1983 (Table 1). The age range of the patients was 11-83 years. Seven were men and twenty-five were women. Fifteen had previous surgery; either clipping of the neck of the aneurysm or ligation of the common carotid artery. Analysis of the hemorrhage associated with the ruptured aneurysms revealed two distinct patterns. One is subarachnoid hemorrhage alone (18 cases) and another is subarachnoid hemorrhage and intraventricular rupture through the temporal horn (14 cases). These aneurysms did not produce a large intracerebral hematoma in the temporal lobe because they ruptured into the temporal horn. Among the post-operative cases (14 cases), only 3 cases had intraventricular hemorrhage. Correlation of these autopsy findings with CT Scans revealed that an intraventricular hematoma in the temporal horn could be interpreted as a large intracerebral hematoma in the temporal lobe.

Adolescent↗
PubMed1984

[Preclinical studies of intra-arterial chemotherapy using mitomycin C microspheres].

Heated albumin microspheres 45 +/- 8 microns dia. containing 5% mitomycin C were infused into rabbit femoral artery to assess the depot effects. MMC levels were measured in the muscle and VX -2 tumor tissues fed by the femoral artery as well as in the drainage vein blood. Furthermore, the histologic changes in the VX -2 tumor and the MMC microspheres entrapped in the arterioles were surveyed microscopically. Drug concentration in the case of MMC microspheres was maintained at high levels in both tissue and venous blood over 4 hours, but in the rabbits infused conventional MMC, drug levels decreased below the assay limitation 2 hours after injection. The microscopic findings 2 weeks later revealed necrotic VX -2 tumor tissue as well as the MMC microspheres remaining in the arterioles .

Animals↗
PubMed1984

[Combined therapy with polyamine biosynthesis inhibitors and mitomycin C].

An attempt was made to analyse tumor growth after cessation of combined therapy with the polyamine biosynthesis inhibitors, alpha-difluoromethylornithine (DFMO) and methylglyoxal-bis-guanylhydrazone (MGBG), as well as mitomycin C (MMC). DFMO 1000 mg/kg, MGBG 50 mg/kg and/or MMC 2 mg/kg were given intraperitoneally to BALB/c nu/nu mice xenotransplanted human gastric cancer, and its growth as well as DNA biosynthesis were measured daily, after cessation of these combined treatments. Histological observation of the tumor was also performed by hematoxylin-eosin staining. The combination with DFMO and MGBG stunted tumor growth during the treatment, but 3 days later its growth and DNA biosynthesis were accelerated distinctly. MMC injection halted tumor growth, and 5 days after termination of MMC injection its growth rate and DNA biosynthesis almost completely recovered. The microscopic findings on the 4th day after termination of MMC injection were similar to those of DFMO + MGBG treatment. The combination DFMO, MGBG and MMC suppressed not only tumor growth during the treatment, but also tumor growth and DNA biosynthesis over 7 days. The histologic observation 4 days later revealed extensive damage.

Animals↗
PubMed1984

[Experimental studies on hepatic cancer chemo-embolization].

Mitomycin microspheres (MMC MS), which contain about 5% of MMC and have an average diameter of 45 +/- 8 microns, were administered into the rat hepatic artery in a preclinical study on antitumor treatment for human hepatic cancer. Plasma GOT and GPT activities increased markedly 24 hours after MMC MS injection; they decreased to within the normal range within 3 days of the injection. Hepatic necrobiosis was observed in the area adjacent to the hepatic arterioles containing MMC MS, but was not observed in rats injected with placebo microspheres. The hepatic vein blood of MMC MS treated rats contained a markedly high level of MMC, compared to rats treated in the conventional fashion with MMC. Furthermore, MMC MS remained within hepatic arterioles for over 3 weeks.

Alanine Transaminase↗
PubMed1984

[Experimental hyperthermo-chemotherapy for human gastric carcinoma transplanted in the nude mice].

Human gastric carcinomas serially xenotransplanted into BALB/c nu/nu mice were treated by hyperthermo-chemotherapy with mitomycin C (MMC). The antitumor efficacy was assessed by both single and double treatments of 25-minute hyperthermia (43.5 degrees C) and/or 2.0 mg/kg of MMC (ip). Tumor weight was estimated using Battelle's Columbus Laboratories protocol. To assess DNA biosynthesis in the tumor cells, the xenotransplanted tumors were excised at prescribed times after these treatments 60 minutes after 3H-thymidine injection (ip), and were examined microscopically. In the group treated twice by hyperthermo-chemotherapy marked growth inhibition and microscopic damage of the tumors were observed, while such features were not recorded in groups treated twice by hyperthermia only and chemotherapy only, nor in groups given single hyperthermo-chemotherapy, or hyperhermia and chemotherapy. In the single-treated groups, DNA biosynthesis was remarkably inhibited by hyperthermo-chemotherapy over 24 hours. The present results suggest that repeated treatments of hyperthermo-chemotherapy with MMC may be effective in the treatment of human gastrointestinal cancer.

Animals↗
PubMed1983

[New management of brain neoplasms. 2. Local injection of adriamycin].

This is the second paper on a trial treatment of malignant brain tumors by postoperative intracavity chemotherapy. In 34 patients with malignant brain tumors in cerebral hemispheres, 0.5 mg adriamycin (ADM) was injected through an Ommaya's device into the tumor-bed every other day after subtotal removal of tumor at craniotomy. Usual total doses of ADM were 5.0-10.0 mg. The patients were usually treated with 60Co-irradiation and immunotherapy after local injection of ADM. Twenty patients with malignant astrocytomas (Kernohan grade 3 or 4) of the cerebral hemisphere were treated with this local injection method of ADM. Clinical effect obtained was 65% and one-year survival rate was 55%. On the other hand, in 14 patients with other malignant brain tumors such as metastatic carcinoma, primary sarcoma, germinoma and medulloblastoma, clinical effect obtained was 36% and one-year survival rate was also 36%. In the autopsy cases of malignant brain tumors, the similar pathological findings were observed as obtained in the patients treated with local injection of bleomycin (BLM). Macroscopically there were extensive necrotic foci, small haemorrhages and increasing fibrin deposit. However, in the cases treated with ADM, the rate of increasing of fibrin debris and necrotic tissues in the tumor cavity were much less than those of in the cases with BLM. Comparative study was carried out on the estimation of the levels of concentration of ADM in the tumor tissues when ADM was injected locally and intravenously. The recurrent tumor tissues were used for the estimation of locally administered ADM.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1983

[Combined antitumor therapy with polyamine biosynthesis inhibitors and mitomycin C].

A combined effect of the polyamine biosynthesis inhibitors, alpha-difluoromethylornithine (DFMO) and methyglyoxal-bis-guanylhydrazone (MGBG) with mitomycin C (MMC) was studied. DFMO, MGBG and MMC were given intraperitoneally to nude mice xenotransplanted human gastric cancer. This new combination of the three drugs resulted in the complete halt of the xenotransplanted tumor growth and marked decline of spermine levels in the tumor tissues. The other treatments with DFMO and MGBG as well as MMC alone were inferior to this new combined therapy in suppression in both tumor growth and tissue spermine level. These data suggest that this new combined treatment be effective against human gastric cancer.

Animals↗
PubMed1983

3-D envisioning by real time perpendicular bi-plane echocardiography (simultaneous multifrequency ultrasonography-III).

Simultaneous dual B-modes, the tomographic plane of which can be moved freely keeping the intersecting angle always perpendicular, was devised and based on simultaneous multifrequency ultrasonography (Miwa, et al, 1981). Dual probes, the ends of which are linked by two arms and three nodes with potentiometers are used to display the intersecting line on the both B-mode images by computation. Both images can be displayed together on one CRT, or separately on the different CRTs. This has proved to be a great help for understanding the 3-D structure of heart. Quantitative dimension and displacement speed measurement of 3-D structure of heart such as myocardium thickness, inner diameter of ventricle, and their changing speed, can be performed very exactly at the accurate three dimensional orientation to the heart. We have also recognized that measuring beam for M-mode must be guided to an exact orientation by this technology. Otherwise, unexpected error has been introduced very usually, if guided only by conventional single B-mode due to lack of information of three dimensional incident angle to the wall, valve,..

Biophysical Phenomena↗