The Use of Technetium-99m for Intravital Tracing of Transplanted Multipotent Stromal Cells.

We studied the possibility of in vivo tracing of multipotent mesenchymal stromal cells labeled with a radiophermaceutic preparation based on metastable isotope Technetium-99m and injected to rats with modeled traumatic brain injury. Accumulation of labeled cells occurred primarily in the liver and lungs. The cells distribution in internal organs greatly varied depending on the administration route.

[Changes in the activity of the mononuclear phagocytic system in inflammatory diseases and atherosclerosis, as evidenced by radionuclide study].

The purpose of the investigation was to determine the activity of mononuclear phagocytes in inflammatory diseases and atherosclerosis at various predominant sites. The mononuclear phagocytic system was studied using labeled compounds, which determined the functional activity of reticular endothelial elements in all tissues of an organism. The analysis of the results of studying the activity of the mononuclear phagocytic system leads to the conclusion that virtually good agreement of the values of the parameters under study in the groups of patients supports the commonness of the processes of development of inflammatory reactions and atherogenesis.

[Radionuclide technique for diagnosing the mononuclear phagocytic system].

The purpose of the investigation was to determine the possibility of using colloidal radiopharmaceuticals to study the mononuclear phagocytic system in the clinical setting. The technique for studying the mononuclear phagocytic system using the labeled compounds involved the single intravenous administration of a radiolabeled colloidal solution, the registration and plotting of a change in colloid radioactivity, and the determination of radioactivity of the body as a whole and that of the lung, liver, spleen, and peritoneum. The performed investigation using colloidal radiopharmaceuticals makes it possible to study the mononuclear phagocytic system and to reveal the regularities of colloid accumulation in the organs and tissues in various diseases just in the clinical setting.

[Structure-activity relationship of cephalosporins. III. Effect of sulfur-containing functional groups on the biological activity of cephalosporins--derivatives of 7-aminocephalosporanic acid].

The relationship between the in vitro antimicrobial activity of cephalosporin antibiotics and the presence and space arrangement of sulfur-containing descriptors of the radical at position 7 in the cefem nucleus was studied. It was noted that the sulfur-containing fragments were markedly less frequent in the structures of the known cephalosporins than the nitrogen- and oxygen-containing descriptors. It was concluded that at present information related only to two of the fragments under investigation might be used as characteristics in predicting antimicrobial activity of cephalosporins by the pattern recognition.

[Structure-activity relationship of cephalosporins. II. Effect of oxygen-containing functional groups on the biological activity od cephalosporins--derivatives of 7-aminocephalosporanic acid].

The statistical analysis of 529 compounds belonging to the group of cephalosporins revealed a significant influence of oxygen-containing descriptors of the radical at position 7 in the cefem nucleus on the biological activity of the compounds. It was concluded that prediction of the antimicrobial properties of the antibiotics by the pattern recognition was possible with using factors reflecting the presence and space arrangement of the following functional groups in the cephalosporin molecules:-OH (phenolic group), C-O-C (ether), C = O (ester, amide) and -O- (in the heterocycle). The results of the study were compared with the data on the impact of nitrogen-containing descriptors on the biological activity of cephalosporins and practical recommendations for synthesis of new active compounds were proposed.