[Nitric oxide metabolites and their significance in pathogenesis of bronchial asthma].

To study the possible potential of nitric oxide (NO) in the processes of atopic inflammation, the authors evaluated the intensity of nitrosyling and oxidative stresses in the bronchoalvelar lavage fluid and expired air condensate of patients with bronchial asthma (BA). Chronic inflammation was shown to result in an increase in the processes of nitration and oxidation in worsening BA and to reliably correlate with airway NO-producing functions, by explaining the pathological effects of NO due to the formation of 3-nitrotyrosine and malonic dialdehyde with the existing imbalance in NO metabolism, by intensifying nitrosylating stress. In the authors' opinion, nitrosothiols that are required as a NO donor may be rapidly destroyed or virtually do not form so the peroxynitrite-nitrosothiol ratio may predetermine the final effects of NO.

[Definition of parameters of the condition of oxidizing stress in smooth muscle cells under influence of exogenous nitroso-glutatyon in vitro].

Influence of exogenous nitroso-glutatyon on intensity of oxidizing processes in smooth muscles of colon and bronchial tubes in intact and atopic sensitised porpoises (guinea pigs) was studied. In sensitised porpoises, antioxidant protection has been initially reduced against the background of increased maintenance of products of oxidizing that reflects a picture of oxidizing damage and can be associated with an inflammatory process. In incubation with nitroso-glutatyon, a decrease in activities of syperoxiddismutase and catalase is marked and, in sensitised animals, this effect has been expressed to a lesser degree.

[Enzymes of purine metabolism of lymphocytes and eosinophiles in bronchial asthma].

The activity of the enzyme purine metabolism (5'-nucleotidase, adenosine deaminase, xanthine oxidase and the content of uric acid, i.e. the final product of the purine metabolism) were determined in lymphocytes, eosinophiles and blood serum of patients with bronchial asthma.

Evidence for formation of somatic cell hybrids in a population of irradiated cells.

Experiments using two genetically marked lines of Djungarian hamster cells (DM-15 HPRT- and DH-TK-) and the technique of hybrid selection in selective HAT medium revealed viable colonies in a mixed culture irradiated with a dose of 5 Gy. The sublines grown from these colonies were examined. Chromosome analysis showed that about 45% of those cells were hybrids inheriting chromosome markers of both parent strains.

[The formation and viability of hybrid cells in a population after irradiation at lethal doses].

With the use of two genetically labeled lines of Djungarian hamster cells and the method of hybrid selection on a HAT-selective medium it was found that in the irradiated mixed culture of the above cell lines, cells were formed that survived in the conditions of total destruction of irradiated parent cells. The chromosome analysis showed that about 45% of the survived cells were hybrids resulting from the radiation-induced fusion of two initial cell lines. These hybrid cells were capable of reproduction.