(2R, 5S) - (+) -cis-3, 5-Dimethyl-2- (3-pyridyl) thiazolidin-4-one hydrochloride (SM 12502), a new PAF antagonist, was labeled with carbon-14 at C 2 of the thiazolidinone ring for use in metabolic studies. The synthesis was achieved according to the scheme illustrated in Fig, 3.14C-Carbonation of 3-pyridyllithium (3) followed by chlorination and esterification gave mehyl [carbonyl-14C] nicotinate (6) . Reduction of 6 with diisobutylaluminium hydride produced a mixture of the alcohol (7) and the aldehyde (8) . Oxidation of the mixture with manganese dioxide gave 8 as a sole product. Condensation of 8 with methylamine and subsequent cyclocondensation of the imine (9) with (S) -2-mercaptopropionic acid (10) yielded a cis and trans mixture of the thiazolidinone (11) . Isolation of the desired stereoisomer by chiralphase HPLC and subsequent treatment with hydrochloric acid afforded 1. The overall yield of 1 was 22% from 2.
In order to develop contrast agents for tumor diagnosis in magnetic resonance imaging (MRI) , we investigated the effects of several gadolinium-complexes on T1relaxation time of proton in some tissues of Ehrlich solid tumor-bearing mice. L-Aspartic acid, L-glutamic acid, DL-homocysteine, L-glutamyl-glutamic acid, glutathione, sperimidine and ethylenediaminetetrakis (methylenephosphate) (EDTMP) were used as ligands for Gd3+.Since each Gd-complex could not be purified except Gd-EDTMP, the mixture of GdCl3 and a ligand was administered intravenously. Among the compounds tested, the mixture of aspartic acid, glutathione or spermidine with GdCl3 showed the almost same or above reduction of T1relaxation times in the tumor tissue compared with Gd-diethylenetriamine pentaacetic acid (Gd-DTPA) which is used clinically. Furthermore, the contrast-enhancing effect of the three mixtures in the tumor was observed by in vivo T1-weighted magnetic resonance imaging. The in vivo tissue distribution using radioactive 153Gd3+ showed that these mixtures mentioned above were also taken up more highly in the tumor than 153GdCl3itself and 153Gd-DTPA, suggesting the formation of Gd-complexes. However, the overall tissue distribution of the mixtures was similar to that of 153GdCl3 because the Gd-complexes were not purified. Gd-EDTMP exhibited the almost same effects with Gd-DTPA as a contrast agent.
Under separate joint research porgrams, clinical trials of radioimmunoimaging with111In-ZCE-025 and IMACIS-1 were performed at our hospital. ZCE-025 is a murine monoclonal antibody (M0Ab) against CEA, and IMACIS-1 is a cocktail composed of131I labeled murine MoAb F (ab') 2 against CEA and131I labeled murine MoAb F (ab') 2 against CA19-9. This report covers the data limited exclusively to our hospital. Five primary colorectal cancer patients were subjected to the study with 111In-ZCE-025. Although high uptake by the liver was noted, all primary lesions were depicted by both planar and SPECT imagings. However, there were some false positive lymph nodes, resulting in a low positive predictive value. Seven patients were subjected to the study with IMACIS-1. Four patients were postsurgical and one patient was pre-surgical for breast cancer. Three of the 4 post-surgical patients were known to have metastases and one was indefinite of recurrence. Besides these breast cancer patients, there were two other patients; one with gastric carcinoma and the other with hepatocellular carcinoma. In this IMACIS-1 group, metastatic lesions from breast cancer were depicted in 2 cases. Although background was low in general, tumor uptakes were not so high.
Uniform 125I disk sources were prepared as a reference source to calibrate NaI (Tl) scintillation detector to measure125I activity on a filter of air monitor in a laboratory. The base of the disk source was a charcoal activated polyurethane foam rubber mat of 75mm in diameter, 2mm in thicknes. 125I disk sources of approximate 0.5kBq, 1kBq, and 10kBq were obtained through immersing disks in ethanol solution containing Na125I of 0.5kBq/ml, 1kBq/ml and 10kBq/ml, respectively, and then drying up them. The uniformity of the distribution of 125I on the disk source was estimated by analyzing the autoradiograph of the disk source using an imaging analyzer. The radioactivity of125I was distributed uniformly on the surface of the disk source within an uncertainty of about 10%.
Wood-plastic combination (WPC) was produced by γ-irradiation of persimmon impregnated with acrylonitrile and styrene. The hardness and strength of WPC obtained zvere higher than those of an unmodified wood. Thus, it was found that the WPC is suited for a head of golf club, because the shore hardness value of WPC is 36% greater than that of unmodified wood. An impregnation method of monomers with some pigments could produce colored WPC without diminishing natural grain. Head of golf club could be manufactured from colored WPC in practice.
High-performance liquid chromatography (H PLC) equiped with on line radiometric and optical detectors have been applied to the radiochemical analysis of ten commonly-used99mTc-radiopharmaceuticals with a view point to check the radiochemical purities of the compounds before use. Chromatographic conditions were determined by examination of the types of column and mobile phase. A gel filtration (Shim-pack DIOL-300) and reversed-phase column (Zorbax ODS) were found to be suitable for99mTc-HSA and the other99mTc-compounds, respectively. From these results, HPLC has been shown to be useful method for the analysis of99mTc-radiopharmaceuticals, with rapidity and excellent precision.