[Certain biochemical blood markers in the process of cholinergic therapy in Alzheimer's disease]. / Nekotorye biokhimicheskie pokazateli krovi v protsesse kholinergicheskoi terapii pri bolezni Al'tsgeimera.

Acetylcholinesterase (AChE) activity and parameters of the system of regulation of lipid peroxidation (LPO) were estimated in blood of patients with Alzheimer's disease (AD) during therapy with amiridine and gliatiline. It was found that the therapy was accompanied by inhibition of AChE activity. A significant correlation was observed between clinical efficiency and changes of AChE activity. AD was characterised by essential changes in LPO parameters: the level of the primary products of oxidation was increased three times with a sharp increase (seven times) of total unsaturation of lipids. A significant correlation was found between AChE activity and the level of the primary products of oxidation in blood erythrocytes of AD patients before and after therapy with amiridine and gliatiline.

[Volume effect and change in compressibility in intercalation of ethidium bromide and daunomycin in DNA]. / Ob''emnyi éffekt i izmenenie szhimaemosti pri interkaliatsii étidiuma bromida i daunomitsina v DNK.

A combination of high-precision and density techniques was used to investigate the binding of ethidium bromide and daunomycin to DNA. It was shown that intercalation is accompanied by a decrease in apparent volume and adiabatic compressibility of DNA, which were -28 cm3mol-1 and -20.10(-4) cm3mol-1bar-1 for binding of ethidium to DNA, and -28 cm3mol-1 and -18.10(-4) cm3mol-1bar-1 for daunomycin, respectively. The values obtained have been compared with those of the hydration contributions of atomic groups to the apparent molar volume and apparent molar compressibility of the ligands as well as the contribution of intrinsic compressibility of DNA. The volume effects in the intercalation of ligands correspond to the values expected for the dehydration of aromatic heterocyclic rings. On other hand, negative compressibility changes may be explained by a decrease of the intrinsic compressibility of DNA and possible increase of its hydration as result of conformational changes upon ligand binding.

[Synthetic bioantioxidants--inhibitors of acetylcholinesterase activity]. / Sinteticheskie bioantioksidanty--ingibitory atsetilkholinésteraznoi aktivnosti.

The inhibitory effects of synthetic antioxidants (3-oxypyridine, pyrimidine and hindered phenols) on the enzymic activity of membrane-bound acetylcholinesterase (AChE) was studied. In terms of estimated kinetic characteristics of AChE-reaction (KM, Vmax, KI), the pattern of enzyme inhibition by the hindered phenol compounds was found to be of non-competitive or mixed type depending on the inhibitor structure or on the substrate acetylcholine or acetylthiocholine used. The comparative study of the inhibitory action of water-soluble derivatives of hindered phenols and fatty-soluble ionol made it possible to reveal possible contributions to the inhibition of both direct and mediated (by the membrane microsurroundings) effects on the membrane-bound AChE by the studied synthetic bioantioxidants.

[The mechanisms of the inhibition of erythrocyte acetylcholinesterase activity by photodynamic herbicides]. / Mekhanizmy tormozheniia aktivnosti éritrotsitarnoi atsetilkholinésterazy nekotorymi fotodinamicheskimi gerbitsidami.

A comparative study of kinetics and mechanisms of action of some photodynamic herbicides (dipyridil, phenantroline, and acepox) on mechanical resistance and acetylcholinesterase activity of erythrocytes has been carried out. Acepox had a slight damaging effect, and phenantroline was the strongest inhibitor. The data on mechanical destruction of erythrocytes correlated with tests on toxicity of obtained samples carried out on mice and infusorians. The proposed criteria may help to search for nontoxic drugs.

[Hemolytic resistance of erythrocytes in the development of experimental tumors]. / Gemoliticheskaia ustoichivost' éritrotsitov pri razvitii éksperimental'nykh opukholei.

Peculiarities of variations in the mechanical resistance of erythrocytes from mice with tumours were studied depending on the growth stage of tumours (lymphoma NK/Ly and sarcoma S-37). The accumulation of erythrocytes with the increased mechanical resistance at the stage of rapid tumour development (on the 4 to 6th days) was revealed by the kinetic method of ultrasonic haemolysis. Quantitative parameters of ultrasonic haemolytic resistance of erythrocytes from normal and tumour-bearing mice were used as criteria for the red blood cell changes depending on the cell age in blood. The increase of haemolytic resistance at the rapid stage of tumour growth may be caused by a higher number of "young" erythrocytes in blood. Ultrasonic haemolytic resistance increases when there is no changes in the erythrocyte quantity and hemoglobin concentration. The kinetic study of ultrasonic haemolysis of the erythrocytes isolated from peripheric blood permits estimating the reaction of the blood forming organs to the origin and development of tumours.

[Effect of chlorine-containing pesticides on the hemolytic stability and acetylcholinesterase activity of erythrocytes]. / Vliianie nekotorykh khlorsoderzhashchikh pestitsidov na gemoliticheskuiu ustoichivost' i atsetilkholinésteraznuiu aktivnost' éritrotsitov.

The hemolytic action of the chlorine-containing pesticides, trichloroacetic acid (TCA), pentachlorophenolate (PCP), chlorophos and pentachloronitrobenzene (PCNB) on red cells was studied, as were their effects on acetylcholinesterase activity and resistance of red cells to mechanical hemolysis by ultrasound. The modifying action of pesticides on red cell membranes was shown to lead to their mechanical resistance. TCA, PCP and chlorophos were found to sensitize red cells whereas PCNB to make them resistant to the mechanical action of ultrasound. The kinetic characteristics of the structural functional disorders of red cells might be used as quantitative criteria of the efficacy of the action of pesticides on the cells.

[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.

[Ultrasonic effects on biological structures]. / Nekotorye osobennosti deistviia ul'trazvuka na biologicheskie struktury.

Several important generalizations can be made concerning the interaction of cavitation ultrasound and biological structures including cellular and molecular phenomena. Physicochemical modifications of nucleic acid bases are independent on whether the bases are individually in sonicated solution or they are incorporated within DNA molecule. The ultrasonic effects involving cavitation phenomena obey pseudomonomolecular (first-order) kinetics, as a function of the amplitude of the acoustic parameter and time of exposure.

[Ultrasonic study of nucleic acids. Effect of pH]. / Issledovanie nukleinovykh kislot ul'trazvukovym metodom, vliianie pH.

The ultrasonic absorption of nucleic acids in water solutions was studied by the pulse ultrasonic technique depending on pH, at frequency 12 mHz T = 20 dedrees C. The obtained data show the occurrence of structural relaxation in DNA solutions caused by the proton exchange and transfer reactions with the extremal pH at 2.5 and 11.7. Possible mechanisms of the excess ultrasonic absorption were discussed concerning the protolytic processes with the charged DNA groups (N--P1 exchange and the hydrolysis of lactam groups at acid and alkaline pH correspondingly).

[Study of the hydration of nucleic acids (DAN and RNA) and their derivatives by an ultrasonic method]. / Izuchenie gidratatsii nukleinovykh kislot (KNK i RNK) i ikh proizvodnykh ul'trazvukovym metodom

Adiabatic compressibilty and the values of hydration of nucleic acids (DNA and RNA) and their derivatives: nucleosides, (cytidine, adenosine, uridine) and adenine nucleotides (AMP, ADP, ATP) in neutral aqueous solutions at T= 25 degrees C have been calculated from the data of measuring the rate of ultrasound propagation and other parameters. The data obtained well agree with the results of other methods.