A comparative study of 99mTc-YIGSR and 99mTc-MIBI uptake in tumor cells / 华中科技大学学报（医学）（英德文版）

To investigate a new kind of tumor tracer 99mTc-YIGSR developed from a five amino structure (YIGSR) of the Laminin -chain, which can bind to the laminin receptors of tumor specifically, and radiolabeled with MAG3. (1) Preparation of the 99mTc-YIGSR probe: with S-Acetly-NH3-MAG3 as the chelator and with proper reductants YIGSR was labeled with 99mTc; (2) Cell culture and viability measurement: EAC was maintained in RPMI 1640 supplemented with calf serum; the trypan blue exclusion was applied to calculate the cell viability; (3) Study of the cell dynamic: The EAC's uptake of 99mTc-YIGSR and 99mTc-MIBI was observed at 37 degrees C and 22 degrees C, respectively. (1) The labeling efficiencies of 99mTc-YIGSR and 99mTc-MIBI were (62 +/- 3)% and (96 +/- 2)%, respectively; (2) The cell viability was declined with time of incubation; (3) At 37 degrees C, the EAC'S uptake of 99mTc-YIGSR and 99mTc-MIBI reached the peak of (43.16 +/- 2.4) % and (24.4 +/- 1.8) % at 60 min, respectively; and at 22 degrees C, the highest uptake was (26.5 +/- 2.1) % and (9.47 +/- 1.9) % at 60 min, respectively. The in vitro study suggests that 99mTc-YIGSR is superior to 99mTc-MIBI in cell uptake and has potential value in tumor imaging.

Radiopharmacokinetics, renal clearance and dosimetry of 99m Tc-MAG3

Background. Technetium-99m-mercaptoacetyltriglycine (99-mTc-MAG3) is a radiopharmaceutical for tubular function and can be prepared with 99-mtechnetium and the ligand Bz-MAG3 (Instituto Nacional de Investigaciones Nucleares, Mexico City). No radiopharmacokinetic parameters have been found for the healty adult Mexican population with 99mTc-MAG3, prepared with the nationally produced or imported Bz-MAG3 kit. Methods. The radiopharmacokinetic parametrs and the clearance of 99mTc-Mag3 in seven healthy Mexican volunteers were determined by the single-and multi-sample methods. Computer programs were used for the calculations. Results. Using several plasma samples from 0.43 min and the BIEXP program, it was show that 99mTc-MAG3 follows a two-compartment model of distribution, with an apparent volumen in the central compartment Vdcc = 6.7 + 1.0 1, T½Ó = 0.07 + 0.02 h-1, T½ ß = 0.49 + 0.15 h-1, mean residence time MRT = 0.60 + 0.17 h and clearance = 208 57 (ml/min)/1.73 m². In comparison, the clearance value with a single sample drawn 43 min post-injection and calculated with Tauxe's formula was 193 ñ 59 (ml/min)/m². Conclusions. The 15 ml difference between the two methods is neither statistically different (p= 0.11) nor important for routine clinical studies. The single-sample method is recommendad because it is reliable and can be done at the same time that dynamic renal scan is aquiered. Estimated absorbed radiation dose was calvulated for several organs