[Dynamics in changes of a1-thymosin level under irradiation of mice thymus in vivo and in vitro: relation to the antibody-antigen production of epithelial thymus reticulum]. / Dinamika izmenenii urovnia a1-timozina pri obluchenii timusa myshei in vivo i in vitro: sviaz s produktsiei autoantitel k antigenam épitelialnogo retikuluma timusa.

In 3- and 9-month experiments with mice, a study was made of the effect of radiation on serum alpha 1-thymosine concentration after whole-body irradiation and local exposure of the thymus at doses of 1-20 Gy. The effect of 137Cs-gamma-rays on the in vitro cultured thymus stroma cells, with respect to alpha 1-thymosine secretion, and the influence of local irradiation of the thymus of production of autoantibodies that react with epithelial thymus cells were studied. Both whole-body irradiation and local exposure of the thymus were shown to cause changes in the alpha 1-thymosine content of the blood plasma. The direction and dynamics of the changes observed are different with whole-body and local exposure. Irradiation of cultured thymus cells of mice causes alterations in alpha 1-thymosine secretion, that is, stimulation at a dose of 1 Gy and inhibition at higher doses. With respect to dose- and time-response, these changes are closer to those observed in alpha 1-thymosine concentration in mouse serum after whole-body irradiation than after local exposure of the thymus in vivo. At remote times after local irradiation of the thymus with doses of 1-10 Gy, autoantibodies are found in mouse serum that react with epithelial cells of the thymus stroma. Autoantibodies are absent at doses of 15 and 20 Gy.

[Effect of modifiers of microsomal enzymes on the enzymatic denitrosation of dialkyl-N-nitrosamines]. / Vliianie modifikatorov mikrosomal'nykh fermentov na fermentativnoe denitrozirovanie dialkil-N-nitrozoaminov.

The antioxidant butyl-hydroxytoluene has been shown to increase denitrosation of some dialkyl-N-nitrosamines by the liver microsomes of different lines of rats and to protect against diethyl-N-nitrosamine toxicity. 3-Methylcholanthrene, while decreasing denitrosation of diethyl-N-nitrosamine, increased its toxic effect. This data suggested that enzymatic denitrosation is an effective pathway for the inactivation of dialkyl-N-nitrosamines.

[Heterogeneity of phospholipid membranes detected by the fluorescent probe method]. / Geterogennost' fosfolipidnykh membran, vyiavliaemaia metodom fluorestsentnykh zondov.

The measurements of fluorescence polarization index within the emission spectra of the fluorescent probes 4-dimethylaminochalcone (DMCh) and 3-methoxybenzantrone (MBA) have indicated that probes are distributed in liposomes prepared from synthetic dipalmitoyl lecithin (DPL) between binding sites of two types. By the method described in the present paper the spectra measured experimentally have been divided into two spectral components. The shape and position of this componential spectra were independent of the probe:lipid concentrations ratio.