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Biomedical subjects

K Hisada

Publications and source records attributed to K Hisada.

At least 217 records · Page 12Linked to original sources
PubMed1987

Biodistributions of 201Tl in tumor bearing animals and inflammatory lesion induced animals.

The accumulation of 201Tl in tumor and inflammatory tissues were small. However, this nuclide showed a high concentration in viable tumor tissue, less in connective tissue (containing inflammatory tissue), and was not seen in necrotic tumor tissue regardless of the time after administration of 201Tl(I)-chloride. In inflammatory lesions, 201Tl accumulated in subcutaneous tissue infiltrated with neutrophils and macrophages, and quite large amounts of this nuclide were accumulated in subcutaneous tissue and sites where neutrophils were crowded. Most 201Tl existed in a free form in the fluid of tumor and inflammatory tissues regardless of the time after administration. A small amount of this nuclide was localized in the nuclear, mitochondrial and microsomal fractions in these tissues, and the nuclide was bound to protein in these fractions. The distribution of 201Tl(III)-chloride in tumor bearing animals was essentially the same as that of 201Tl(I)-chloride.

Animals↗
PubMed1987

Effect of roasting on ochratoxin A level in green coffee beans inoculated with Aspergillus ochraceus.

The heat stability of ochratoxin A in green coffee beans inoculated with Aspergillus ochraceus was studied. Heat treatment (roasting) at 200 degrees C for 10 or 20 min reduced the levels of ochratoxin A by only 0-12% in the dried whole beans. Almost all of the ochratoxin A was infused into the coffee decoction when the roasted samples were ground and extracted with boiling water. Therefore, the reduction of ochratoxin A concentration of contaminated coffee beans by roasting under these conditions is ineffective.

Aspergillus↗
PubMed1987

Distribution of 46Sc and 51Cr in tumor-bearing animals and the mechanism for accumulation in tumor and liver.

Tumor uptake rates, concentrations in mitochondrial fraction (containing lysosome) of liver and tumors, avid accumulations in connective tissue (especially inflammatory tissue) and binding substances in these tissues for 46Sc3+ and 51Cr3+ were essentially similar to those for 67Ga3+, 111In3+, 169Yb3+, 167Tm3+, 95Zr4+ and 181Hf4+. However, the main binding substance of 46Sc3+ and 51Cr3+ in tumor and liver was the acid mucopolysaccharide (as described concerning 95Zr and 181Hf) whose molecular weight exceeded 40,000, although the main binding substance of 67Ga3+, 111In3+, 169Yb3+ and 167Tm3+ was the acid mucopolysaccharide with a molecular weight of about 10,000.

Animals↗
PubMed1987

Quantitative estimation of hemorrhage in chronic subdural hematoma using the 51Cr erythrocyte labeling method.

Red cell survival studies using an infusion of chromium-51-labeled erythrocytes were performed to quantitatively estimate hemorrhage in the chronic subdural hematoma cavity of 50 patients. The amount of hemorrhage was determined during craniotomy. Between 6 and 24 hours after infusion of the labeled red cells, hemorrhage accounted for a mean of 6.7% of the hematoma content, indicating continuous or intermittent hemorrhage into the cavity. The clinical state of the patients and the density of the chronic subdural hematoma on computerized tomography scans were related to the amount of hemorrhage. Chronic subdural hematomas with a greater amount of hemorrhage frequently consisted of clots rather than fluid.

Adolescent↗
PubMed1987

[Investigation of 99mTc labeled tumor seeking agents--usefulness of 99mTc-isoniazid].

For the development of 99mTc labeled tumor seeking agents, 273 drugs and chemicals were evaluated. Agents labeled by SnCl2-HCl method were injected to rats bearing Yoshida sarcoma. Scintigrams of the rats 2 hours after injection and the excised tumor and organs placed on a plate were taken and evaluated their affinity to the tumor. Isoniazid (INH) was found to be the most useful agent as a result of this screening study. Intensive study on 99mTc-INH was subsequently performed. Another labeling method, FeSO4-H2SO4 method, was evaluated and shown to be superior in both absolute tumor uptake and tumor to muscle ratio. Uptake of 99mTc-INH to Yoshida sarcoma occurred early after injection and maintained its level until later time. On the other hand, radioactivity in the blood and muscle decreased rapidly; that is, tumor to blood and muscle ratio showed rapid increase. Other animal tumor models, mouse bearing Ehrlich tumor or Sarcoma 180, were also used to evaluate the usefulness of 99mTc-INH. The labeled agent showed good localization in these tumors too. In conclusion 99mTc-INH might be a good tumor seeking agent and further clinical trials would be warrant.

Animals↗
PubMed1987

[Scintigraphy with 111In-labeled leukocytes: simplified procedure for labeling].

To utilize 111In leukocytes in a routine work, simplified procedure for sterile leukocytes preparation and labeling with water soluble oxine sulfate was performed. Viability and chemotaxis of leukocytes were maintained during separation and labeling. Chelated rate of 111In with oxine sulfate was 93.5%. Labeling efficiency of 111In leukocytes was 93.8%. Obvious blood pool images due to remained erythrocytes were not observed. 111In labeled leukocytes showed good migration into inflammatory focci.

Humans↗
PubMed1986

Clinical studies on diabetic myocardial disease using exercise testing with myocardial scintigraphy and endomyocardial biopsy.

Nine diabetics without significant coronary stenosis participated in an exercise testing protocol with thallium-201 myocardial scintigraphy. Endomyocardial biopsy of right ventricle was also obtained. There were 4 patients with abnormal perfusion (positive group) and 5 patients with normal perfusion (negative group). All cases of the positive group were familial diabetics and there was only one case of dietary treatment, whereas in the negative group, there were only 2 cases of familial diabetics and 3 cases receiving dietary treatment. No statistical differences between the positive and negative groups were observed for the data of exercise performance and hemodynamic parameters in cardiac catheterization at rest. However, the mean ejection fraction in the positive group (62 +/- 13%) was significantly lower than in the negative group (77 +/- 4%). In both groups, the mean diameter of myocardial cells and the mean percent fibrosis of biopsy specimens showed significant increases compared with the control group. The mean percent fibrosis in the positive group (24.1 +/- 8.5%) compared with that in the negative group (16.5 +/- 5.9%) showed a tendency to increase. It is suggested that the abnormal perfusion of thallium-201 in the positive group indicates subclinically a pathological change of microcirculation caused by diabetes mellitus.

Adult↗
PubMed1986

A single-strip mini-paper chromatographic method for rapid purity-control of 99mTc-labeled radiopharmaceuticals.

A single-strip miniaturized paper chromatographic method (Mini-PC) was developed using 80%-90% acetone solvent for rapid purity-control of 99mTc-radiopharmaceuticals. Routine 99mTc-radiopharmaceuticals (eight kinds of "kit" made agents) and diluted agents (in which radiochemical impurities might be formed) were analyzed by Mini-PC and other methods. This showed that, compared with the other methods, the Mini-PC technique is useful for the simple and rapid routine analysis of radiochemical impurities of "kit" made 99mTc-radiopharmaceuticals.

Chromatography, Paper↗