[Regularities of endogenous lipid metabolites formation in phorbol 12-miristate 13-acetate-stimulated peripheral blood lymphocytes at leukemia].

Regularities of biologically active lipid metabolites formation in dynamics (5, 10, 30, 60 s) by phorbol 12-miristate 13-acetate stimulation in [14C]palmitic acid have been investigated in normal and leukemia peripheral blood lymphocytes prelabeled with [14C]palmitate. In normal cells there was two-phase formation of 1,2-diacylglycerol (5, 30 s), lysophosphatidylcholine (10, 60 s), as well as free palmitic acid at 10 s of stimulation. Under the identical experimental conditions there was inhibition of investigated lipid release processes at early (5 and 10 s) stages of stimulation of leukemic lymphocytes.

[The influence of low-energy millimeter electromagnetic waves on the stability of DNA molecules in solution].

The influence of low-energy millimeter electromagnetic waves on aqueous saline solution of DNA from the liver of healthy rats and rats with sarcoma 45 has been investigated. The characteristic parameters of irradiated and unirradiated DNA, melting temperature, and the range of melting were obtained from melting curves. The duration of exposure did not practically affect the range of melting, while the thermostability of DNA increased; as irradiation duration increased to 90 min, the melting temperature of tumor increased by approximately 1.

[A novel method of analysis of ligand-polynucleotide adsorption isotherms].

The adsorption of ethidium bromide on the synthetic double-stranded polyribonucleotide poly(G)poly(C) was investigated by adsorption spectroscopy. The adsorption isotherms were analyzed in the framework of the Crothers-Gursky model. It was shown that adsorption parameters (e.

[Formation of complexes between DNA and cationic amphiphile molecules by the fluorescent probe method].

The formation of complexes of DNA with dodecylamine, dodecyltrimethylammonium, tetradecyltrimethylammonium, and hexadecyltrimethylammonium was studied using a fluorescent probe pyrene. The dependences of the spectral parameters of the hydrophobic pyrene probe on the concentration of the cationic amphiphile in the presence and absence of DNA were obtained and analyzed. It is shown that, in the absence of DNA, these dependences exhibit only one S-shaped region, which corresponds to the micelle formation of the amphiphile, whereas in the presence of DNA there are two S-shaped regions, which indicates the cooperative formation of two types of DNA-cationic amphiphile complexes.

[The study of the interaction of antineoplastic drugs mitoxantrone and ametantrone with DNA using the analysis of changes in circular dichroism spectra].

The influence of the ionic strength and temperature of medium on the changes in the geometry of the double stranded DNA of different nucleotide content upon the formation of complexes with antitumor drugs mitoxantrone and ametantrone was investigated. It is shown that from circular dichroism spectra it is possible to determine the relative intensity of changes in the geometry of DNA double helix upon binding with the drugs investigated. The binding of one ametantrone molecule causes greater changes in the geometry of DNA double helix than the binding of mitoxantrone.