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Biomedical subjects

H Niitani

Publications and source records attributed to H Niitani.

At least 199 records · Page 11Linked to original sources
PubMed1981

Regional changes in cardiac structural proteins in myocardial infarction: biochemical and histologic correlates.

1. Quantitative analysis of structural proteins from a minute amount of myocardial tissue was performed from 10 mu thick cardiac tissue slices weighing 2 to 5 mg by the extraction in glycerol solution and by sodium dodecylsulfate (SDS) gel electrophoresis, and these changes were compared with the histologic alterations in the striated structure of the adjacent cardiac slices in the experimental myocardial infarction in the dog. 2. Approximately 69 micrograms of structural proteins were obtained from 1 mg of the normal heart muscle. In the central portions of the myocardial infarction, reductions in myosin heavy chain (HC), light chain (LC) 1 and alpha-actinin were observed at 12 to 24 hours after the coronary occlusion followed by the decrease in myosin LC 2 at 48 hours. Those changes became intense at 72 hours to 7 days, but restored gradually at 14 to 28 days. 3. Alterations in the striated structure of cardiac muscle fibers of the adjacent tissues slices were found simultaneously with the changes in structural proteins. At 12 to 24 hours after the coronary ligation increase in eosinophilia and overstretch of cross-striation were observed. The findings of coagulation necrosis, loss of striation, fragmentation, swelling of A-band, etc. of the infarcted fibers were markedly observed at 48 hours to 7 days, but the histologic restoration of cardiac fibers was found with the recovery of the infarcted tissue at 14 to 28 days after the coronary ligation. 4. Changes in the compositions of structural proteins corresponded well to the alterations in the striated structure in chronology and in quantity.

Actinin↗
PubMed1981

Alterations in cardiac troponin subunits in myocardial infarction.

1. Alterations in troponin subunits in myocardial infarction were studied in the dog heart by the analysis of troponin-tropomyosin complex, i.e, native tropomyoin, of total structural proteins in SDS gel electrophoresis, and by the measurement of degree of activation of actomyosin-ATPase by Ca++. 2. At 12 to 24 hours after coronary ligation, reductions in TN-C and tropomyosin were observed followed by a decrease in TN-I at 48 hours. The relative contents of these subunits were the lowest at 72 hours to 7 days falling to less than 10% of those in the non-ischemic myocardium. On the contrary, TN-T was preserved through the course of myocardial infarction. 3. Actomyosin-ATPase activity was increased at 12 to 24 hours after coronary ligation and then reduced rapidly at 24 to 48 hours together with the degradation of myosin. However, the activation of actomyosin-ATPase by Ca++-troponin-tropomyosin was reduced already at 12 hours simultaneously with the reduction in TN-C, and almost completely lost at 48 hours. 4. Troponin subunits and actomyosin-ATPase activity returned to those of the control myocardium at 28 days after coronary ligation indicating the recovery of infarcted tissue.

Adenosine Triphosphatases↗
PubMed1980

Experimental and clinical effect of ACNU in Japan with emphasis on small-cell carcinoma of the lung.

The experimental and clinical effects of ACNU so far recorded in Japan are reviewed. ACNU was highly effective in leukemia L-1210 and in other types of leukemias, ascites tumors, and solid tumors of mice and rats. On the basis of the results of phase I study, the maximum clinically tolerable single dose of ACNU was 101.8-135.7 mg/m2 at a time, and the total acceptable dose was 300-600 mg. The desirable interval between doses was 6-8 weeks. Phase II study revealed that ACNU seemed to be effective against small-cell carcinoma of the lung, brain tumors, Hodgkin's disease, and chronic myelocytic leukemia. In the treatment of small-cell carcinoma of the lung ACNU reduced the rate of brain metastasis and prolonged the survival of patients.

Animals↗
PubMed1980

Comparison of survival in nonresected well differentiated and poorly differentiated adenocarcinoma of the lung.

One hundred nineteen cases of advanced adenocarcinoma of the lung were divided into well differentiated adenocarcinoma (72 cases) and poorly differentiated adenocarcinoma (47 cases) histologically and/or cytologically. The median survival of 72 cases of well differentiated adenocarcinoma (7.9 months) was significantly (P less than 0.025) longer than that of poorly differentiated adenocarcinoma (4.9 months) irrespective of stage, difference in treatment regimen, or response to treatment. In 9 evaluable cases, the objective response rate to chemotherapy was 25% (6/24) in poorly differentiated adenocarcinoma and 11.3% (8/71) in well differentiated adenocarcinoma, respectively. In 45 patients who received a combination of chemotherapy and radiotherapy, the median survival of 22 well differentiated adenocarcinomas (11.8 months) was significantly (P less than 0.05) longer than than of 23 poorly differentiated adenocarcinomas (5.6 months). The same tendency was observed in 74 patients who received chemotherapy alone. Analysis based on the grade of differentiation is essential for the accurate assessment of the efficacy of treatment in adenocarcinomas of the lung.

Adenocarcinoma↗
PubMed1979

Effect of 1(4-amino-2-methyl-5-pyrimidinyl) methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) on Sato lung carcinoma (SLC). Preliminary result of immunochemotherapy for SLC by combination of ACNU and Propionibacterium acnes.

ACNU was highly effective for Sato lung carcinoma transplanted intravenously or intramuscularly by using a large single dose, and the cytotoxic action of ACNU for SLC showed clear dependence upon tumor size. Nonspecific activation of host-defence mechanism by Propionibacterium acnes contributed to the suppression for the regrowth of solid SLC treated by ACNU.

Animals↗
PubMed1979

Combined effect of BCG and coenzyme Q10 on ATP-ase activity and coenzyme Q content in spleen lymphocytes of tumor-bearing rats.

Effect of BCG, coenzyme Q10, or their combination on ATPase activity in spleen lymphocytes of tumor-bearing rats was investigated in relation to changes in the content of individual coenzyme Q homologs in these cells. Contents of both coenzyme Q9 and Q10 in spleen lymphocytes significantly decreased in the late stage of Donryu rats bearing Sato lung carcinoma. Oligomycin-sensitive ATPase activity in spleen lymphocytes was also significantly depressed in this stage. The depressed, oligomycin-sensitive ATPase activity was significantly recovered by a 3-time intramuscular administration of coenzyme Q10 emulsified with ethanol and saline, and the decreased contents of coenzymes Q9 and Q10 were slightly restored by this treatment. This enzyme activity was also significantly recovered by an intravenous administration of BCG, and was elevated more by the combined treatment with BCG and the emulsified coenzyme Q10. These results suggest that the combined treatment with BCG and emulsified coenzyme Q10 can contribute to the improvement of the depressed bioenergetics in lymphocytes of tumor-bearing animals, and that this combined effect of BCG and emulsified coenzyme Q10 might be based on the combination of their individual activating effect on lymphocytes.

Adenosine Triphosphatases↗
PubMed1979

Effect of BCG on cytostatic activity of peritoneal macrophages from normal and tumor-bearing rats.

In tumor-bearing rats inoculated intramuscularly with 5 x 10(4) SLC cells, the cytostatic activity of peritoneal macrophages was elevated in the early stage (7 days after transplantation) and decreased in the advanced stage (21 days after transplantation). When BCG was intraperitoneally administered into normal and tumor-bearing rats, peritoneal macrophages showed higher cytostatic activity than the untreated macrophages. This elevated cytostatic activity of the marcophages obtained from BCG-treated tumor-bearing rats was maintained even at an advanced stage.

Animals↗