[Features of organic nonelectrolyte binding to the erythrocyte membrane]. / Osobennosti sviazyvaniia organicheskikh neélektrolitov éritrotsitarnoi membrany.

The capacity of erythrocyte membranes for organic nonelectrolytes from different chemical groups of chemical compounds was studied by the spin probe method and scanning electron microscopy. Hydrophobic spin-labeled derivatives of gamma-carbolin and stearic acid and the screened phenol antioxidant fenozan-1 were used as nonelectrolytes. Based on the analysis of electron spin resonance spectra of the hydrophobic spin-labeled nonelectrolytes and electron micrographs of erythrocytes, differences in the capacity of distribution regions in the intramembrane space of the derivative of gamma-carbolin and fenozan-1, on the one hand, and the spin-labeled derivative of fatty acid, on the other hand, were found. The first group has at least two membrane distribution regions, whereas in the second case only one type of distribution was found. The influence of limited membrane capacity on the realization of biological activity of organic nonelectrolytes is discussed.

[Changes in the surface architectonics of erythrocytes under the influence of the synthetic antioxidant fenozan-1]. / Izmeneniia poverkhnostnoi arkhitektoniki éritrotsitov pod vliianiem sinteticheskogo antioksidanta fenozana-1.

Scanning electron microscopy revealed changes in erythrocyte morphology induced by the synthetic antioxidant phenozan-1. Phenozan-1 at 10(-7)-10(-5) M acts as an echinocytogen. This effect of the antioxidant is, probably, due to its distribution in the external monolayer of the erythrocyte membrane and associated structural changes.

[A comparative study of the action of 1-methyl-1-nitrosourea and 1,3-dimethyl-1-nitrosourea on tumor cell DNA in vitro and in vivo by the alkaline elution method]. / Sravnitel'noe izuchenie deistviia 1-metil-1-nitrozomocheviny i 1,3-dimetil-1-nitrozomocheviny na DNK opukholevykh kletok in vitro i in vivo metodom shchelochnoi éliutsii.

DNA damage of the tumor cells was studied by the method of alkali elution from filters after introduction of 1-methyl-1-nitrosourea (MNU) and 1,3-dimethyl-1-nitrosourea (DMNU) to mice with Ehrlich ascites carcinoma or after treatment of the cultivated cells with these drugs. DNA was essay fluorometrically using DAPI. The degree of DNA damage was characterized by the constant of the alkali elution rate (Kae), which was estimated according to the anamorphism of the kinetic curves of elution. It was shown that in the case of MNU application the tumor cell DNA was damaged to a greater extent than in the case of DMNU application. Kae increased with the concentration of drugs. A correlation was established between the antitumor activity of the drug (kappa), K(ae), and the number of chromosome defects per cell (gaps, deletions, microfragments, ring chromosomes, and translocations). This suggests that kappa is due both to DNA damage and chromosome defects.

[Structural and biochemical parameters of blood components of mice after gamma irradiation with small doses of different intensity]. / Strukturnye i biokhimicheskie pokazateli élementov krovi myshei posle gamma-oblucheniia v malykh dozakh raznoi intensivnosti.

The complex study on the low gamma-irradiation on the structural feature of lymphocyte DNA and lipid peroxidation (LPO) regulatory system parameters in mice blood was carried out depending on irradiation intensity. It was found that DNA alkaline elution rate constants, viscosity of the different regions of erythrocyte membranes and LPO products content in mice blood plasma varied nonlinearly depending on dose or dose rate. The proportion of the damage types and the range of the DNA structural changes substantially differ depending on the gamma-irradiation dose and its intensity. It is considered that the proportion of the DNA and membrane damage and repair can change depending on radiation dose and dose rate.

[Characteristics of sulfhydryl groups of histone H3 from the calf thymus using mercury-containing nitroxyl radicals]. / Kharakteristika sul'fgidril'nykh grupp gistona H3 iz timusa telenka s pomoshch'iu rtut'soderzhashchikh nitroksil'nykh radikalov.

The interaction between total histone and deoxyribonucleoprotein (DNP) preparations from calf thymus with mercury-containing nitroxyl radicals in low ionic strength solutions, 2 M NaCl and urea was investigated. It was found that the label is rapidly incorporated into the SH-groups of histone H3 to produce characteristic EPR signals. Titration of SH-groups within DNP demonstrated that in low ionic strength solutions only one SH-group (presumably, the SH-group of the cysteine residue in position 110) is accessible to the reagents. After dissociation by 2 M NaCl, two SH-groups become titrable; however, the EPR spectra point to differences in the conformational state of these two groups. In 4 M urea, these differences are compensated for by structural disintegration. The spin labels may be used for the analysis of SH-groups under different conditions and at different functional states of nucleoproteins.

[Ultrasonic hemolysis of normal and pathological erythrocytes]. / Izuchenie ul'trazvukovogo gemoliza éritrotsitov v norme i pri patologii.

The kinetic method of the investigation of erythrocyte haemolysis normal and at different tumour pathologies by ultrasound was developed. The quantitative parameters of the mechanical resistance of erythrocytes were studied (time and velocity of haemolysis, time of half-destruction, the distribution of erythrocytes by their haemolytic resistance). The studied parameters differ between the normal state and the tumour in organism. The analysis of the differential distribution of erythrocytes by their resistance to ultrasonic haemolysis revealed the occurrence in the patient's blood of erythrocytes with increased resistance ("young" erythrocytes). The mechanical resistance of the erythrocytes at pathology was shown to increase as compared with the normal state. The differences in the effective constants of ultrasonic haemolysis velocity were estimated for the normal state and for different tumours. They are caused by the changes in visco-elastic properties of red blood cells.