[en] Unscheduled DNA synthesis was induced by UV irradiation of spleen cells obtained from C 57 Bl mice after repeated total body irradiation of 0.05 Gy ⁶⁰Co (0.00125 Gy/mice) and determined autoradiographically. An enhancement in the ability for repair of UV induced DNA lesions was observed in cells of gamma irradiated animals. While the amount of ³H-thymidine incorporated per cell was increased, the percentage of labeled cells remained unchanged. The present results are compared with previous data on low dose radiation exposure in men. (Author)

[en] 30 female C57 bl. mice were treated with adenocarcinoma im. in the right hind leg. Three days later, cis-dichlorodiamine platinum was applied orally (15 mg/kg) to all animals and additional 0.05 mg prednisolone i.p. to 20 animals. Tissue samples from blood, liver, kidneys, spleen, heart, lungs, tumors and gastrointestinal tract were analyzed for their Pt concentrations after therapy with cis-dichlorodiamine platinum complexes and prednisolone by instrumental neutron activation analysis. The amount of Pt in most organs examined remained under 0.05% of the quantity applied. Maximum values were detected at the end of the experiment, except for the gastrointestinal tract, the liver and the kidneys. Treatment of the animals with prednisolone did not produce a significantly different distribution of Pt. Only in tumor tissues a significantly higher amount of Pt was observed after prednisolone treatment at 48 h but not at 72 h. Blood levels increased with time after prednisolone treatment, without prednisolone, blood levels decreased. (author)

No abstract available

[en] The title complex were prepared from no-carrier-added sup(99m)Tc-TcOsub(4)sup(-) and the air-sensitive reducing ligand DMPE under argon in ethanol-water. At acidic pH [Tc(III)Clsub(2) dmpesub(2)]sup(+) was formed, while alkaline pH led to the formation of 95% yield in less than 1 hour, otherwise the [Tc(V)Osub(2)dmpesub(2)]sup(+) intermediate was present. Electrophoresis demonstrated the unit positive charge and reversed-phase ion-pair HPLC provided separation and identification of sup(99m)Tc-products by direct comparison with known sup(99m)Tc-complexes. In rats the sup(99m)Tc-complexes were excrated by kidneys and liver and reached high heart/blood but only low heart/lung and heart/liver ratios. In dogs satisfactory myocardial scintigrams were obtained in spite of high liver activity. (author)

[en] Accumulation of a radioactive label in tumor tissue is required for scintigraphic visualization of the tumor and has been achieved by application of bleomycin as carrier. This chemotherapeutic polypeptide drug has been labeled with ⁶⁴Cu. Thin layer chromatography of ⁶⁴Cu-bleomycin which was incubated for 22 hours at 37⁰C showed no changes of the chelate. When urine of the ⁶⁴Cu-bleomycin treated animals was chromatographed considerable amounts (9.3%) of free ⁶⁴Cu appeared 2 hours after injection of the chelate and dissociation was found to be almost complete 4 hours after injection of labeled bleomycin. The distribution of ⁶⁴Cu-bleomycin is similar to that found with sup(99m)Tc-bleomycin with long lasting accumulation in kidneys and liver. Highest concentration ratios of the activity in mesenchymal tumor (Yoshida) and blood respectively were found 6 hours after intravenous administration of ⁶⁴Cu-bleomycin. (author)

[en] For the preparation of sup(99m)Tc-TBI, ligand exchange (a) and direct reductive complex formation from TcO₄-(b) were studied. HPLC analysis (RP C18) revealed a 2nd sup(99m)Tc compound from (a) only; therefore, reaction conditions for (b) were optimized in a parameter study. Finally sup(99m)Tc-TBI was obtained at 97 % yield and purified from ligand by prep HPLC or Sep Pak C18. Biodistribution in mice showed rapid blood clearance, initial high uptake in lungs and prominent persisting activity in liver and heart. Clinical studies showed a corresponding pattern in patients yielding high-quality myocardial scintigrams at and after 1 hour p.i.. Liver activity was the main interference, especially in the inferior apical region. In resting studies transmural infarction was seen as reduced accumulation, whereas non-transm. inf. and ischemic regions were only detected after stress. In contrast to ²⁰¹Tl these stress-induced perfusion defects persisted for 6 hrs. The compound deserves further clinical evaluation. (Author)