[Experience of the development special medical technical laboratory for studies of effects caused by potent electromagnetic radiation in biologic objects].

This article covers topics of creating special medical technical laboratory for medial and biologic studies concerning influence of potent high-frequency elecromagnetic radiation on various biologic objects. The authors gave example of such laboratory, described its construction features, purpose and main characteristics of the included devices.

Bis-benzimidazole anticancer agents: targeting human tumour helicases.

Certain DNA minor groove binding agents, distamycin, netropsin, and a series of anticancer bis-benzimidazoles can block DNA helicase activity by binding to duplex DNA at specific base sequences. DNA helicases are crucial to cell DNA replication, transcription and repair because these enzymes separate double-stranded DNA, thereby preparing the strands for enzymatic manipulation. From our studies we have developed a hypothesis that focuses on cellular DNA helicase action as a mechanistic site where these minor groove binders can act. A crucial aspect for modulation of DNA activity by drugs is for specificity and selectivity. A series of DNA-interactive bis-benzimidazole analogues of Hoechst 33258 was also prepared to explore the potential for anticancer activity mediated for certain of the drugs via bioreductive activation by endogenous NADH or NADPH. The biological endpoints examined included intracellular distribution in euoxic and hypoxic conditions observed by fluorescence microscopy; relative efficacy as antimetabolites determined by the MTT [tetrazolium salt, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay in euoxic and hypoxic conditions; and relative inhibitory activities on human DNA helicase, as determined by degree of dissociation of GC B6486 DNA. The intracellular distribution was unique to each of the test compounds. Compounds V-93 and V-153, the respective semiquinone and quinone derivatives, demonstrated the predicted enhanced cytotoxicity and anti-helicase activities, supporting the concept that preferential binding of DNA at 5'-CG and TG sequences provides a novel approach to anticancer drug development.

Repeated BCG vaccination is more effective than a single dose in preventing diabetes in non-obese diabetic (NOD) mice.

Stimulation of the non-obese diabetic (NOD) mouse immune-system with a single bacillus Calmette-Guerin (BCG) vaccination can inhibit the development of diabetes. The optimal dose, and the time and number of vaccinations is still to be clarified. In this study we evaluated the protective effect of repeated BCG vaccinations on preventing diabetes in NOD mice. 17/32 (53%) of the control group, 8/31 (26%) of the single vaccine-treated (at age 35 days) mice, and 7/23 (30%) of the single vaccine-treated (at age 90 days) mice developed diabetes, and none of the repeated BCG vaccination (at age 35 & 90 days, n = 14) animals developed the disease, up to 250 days of age (p < 0.05, compared with controls and each of the single-vaccination groups). While the severity of insulitis was lower in repeatedly BCG-treated mice at age 120 days as compared with controls and single BCG-vaccination groups, we could not detect significant differences in the Intracellular adhesion molecule-1 (ICAM-1) expression between the various groups. There were no differences in weight gain and blood hematocrit between the different groups. Our report demonstrates that repeated BCG vaccination is safe and more effective than a single dose in preventing type I diabetes in NOD mice. This data should be considered in planning new human trials with BCG.