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Biomedical subjects

K Hisada

Publications and source records attributed to K Hisada.

At least 451 records · Page 25Linked to original sources
PubMed1977

[Tumor affinity of 99mTc-labeled radiopharmaceuticals, 99mTc-Sn-urokinase and 99mTc-Sn-mannitol].

Biolgic distribution of 99mTc-labeled fibrinolytic agent, urokinase, and 99mTc-labeled mannitol, which was obtained as a side-product in the preparation of 99mTc(Sn)-urokinase, have been studied in Ehrlich's tumor-bearing mice to get a promising indicator for the positive delineation of malignant tumor. The preparation of 99mTc-labeled radiopharmaceuticals, 99mTc-UK and 99mTc-Man, was made by the reduction with stannous chloride and labeling efficiency was examined by Sephadex G-25M gel chromatography and by silica gel plate thin layer chromatography. Labeling yield of 99mTc-UK by Sephadex G25M in 0.9% NaCl eluant was 13% and that of 99mTc-Man by TLC in 85% methanol solvent was over 95%. A higher uptake to the implanted solid tumor tissue in mice was found in 99mTc-Man than in 99mTc-UK, of which the excellent tumor accumulation was expected from the positive delineation of malignant tumor with 131I-fibrinogen, 131I-fibrinogen antibody and 125I-plasmin. The poor result in 99mTc-UK, however, may be attributed to the poor fibrinolytic activity of Ehrlich's tumor. In biologic distribution of 99mTc-UK was found high concentration for liver kidney and stomach. In the other hand, a higher tumor tissue uptake, a fast blood disappearance and a low concentration for different organs were found in biologic distribution of 99mTc-Man. Therefore, 99mTc-Man may be assumed as a more preferable 99mTc-labeled tumor localizing radiopharmaceuticals, to which it would be needed as absolute biologic characteristics that 99mTc-labeled compounds possess a high tumor uptake as well as a fast blood disappearance with a low uptake for different organs. However, the possible delineation with 99mTc-labeled fibrinolytic agents, including urokinase and streptokinase, may be promised for malignant tumors in human-subject, which generally have a higher activity in fibrinogenesis than in fibrinolysis.

Animals↗
PubMed1977

[Diagnosis of cold thyroid nodules by 201T1 scientigraphy].

Fifty two patients with cold thyroid nodule demonstrated on the thyroid scan were imaged with 201Tl which were given intravenously as thallium chloride in dose of 2 mCi. Thirty nine of 52 patients were confirmed and investigated whether 201Tl concentrated or not. Fourteen of 15 (93 percent) thyroid carcinomas, 5 of 17 (29 percent) thyroid adenomas, 1 of 2 adenomatous goiters and all of 5 of chronic thyroiditis were visualized as positive with 201 Tl. One thyroid carcinoma did not concentrate 201Tl which was confirmed to have cystic degeneration. Of the 19 benign cold thyroid nodules except chronic thyroiditis 6 were positively visualized with 201Tl. However, 201Tl did not accumulate in the other 13 benign nodules, 11 out of which were confirmed to have cystic degeneration. The data suggests that if the thyroid nodule is found to have negative accumulation of 201Tl, malignancy can be ruled out except a small microscopical lesion.

Adenocarcinoma↗
PubMed1977

[Whole-body retention studies of 169Yb-citrate.--Estimation of radiation dose to humans from 169Yb-citrate (author's transl)].

For purpose of the estimation of the radiation dose to humans from 169Yb-citrate, the whole-body retention studies using five rats were carried out. Following intravenous administration of 169Yb-citrate, the whole-body activity was monitored for 40 days by the animal counter. The whole-body retention curve consisted of three components: the first with a 3.6 hours effective half-time, the second with an 154 hours effective half-time and the third with a 29.9 days effective half-time. Therefore it was assumed that 32% of the administered 169Yb-citrate clears from the kidney with a short biologic half-time (3.6hours), 18% remains in the liver and other soft tissues with a relatively long biologic half-time (194 hours) and 50% remains in the bone with a long biologic half-time (850 days). Based on these biological data and the MIRD Committe method, the average dose to the bone and whole-body were 20.8 rads/mCi and 4.5 rads/mCi respectively.

Animals↗
PubMed1977

[Study of distribution of 203Hg-chlormerodrin, 203Hg-nitrate and 99mTc-DMSA in kidney by macroautoradiography (author's transl)].

Serial macroautoradiograms were obtained to determine the distribution of 203Hg-chlormerodrin, 203Hg-nigrate and 99mTc-DMSA in kidney. In the study, normal rats were used and these three radiopharmaceuticals were injected intravenously. Initial images of 203Hg-chlormerodrin showed the accumulation in the outer cortex, but no significant radioactivity in the medullary. On the other hand, delayed images revealed radioactivity shifting in concentration from the outer cortex to the inner cortex. Distribution pattern of 203Hg-nitrate was similar to that of 203Hg-chlormerodrin. In contrast to 203Hg-chlormerodrin and 203Hg-nitrate, 99mTc-DMSA was retained in the outer cortex without temporal changes in the distribution.

Animals↗