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M M Vilenchik

Publications and source records attributed to M M Vilenchik.

30 records · Page 2Linked to original sources
PubMedDate not supplied

[Synergistic mechanisms in the combined carcinogenic action of radiation and other factors: the role of mutation and the activation of oncogenes and genes controlling growth factor synthesis].

A hypothesis is proposed on the role in the radiation carcinogenesis of mutation and (or) activation of combination of the several prooncogenes, some of which are homologous on the growth factors or probably to the actin. The antibodies to the products of oncogenes may be used to study mechanisms of carcinogenic action of radiation and others factors or even as diagnostic tool or remedy.

Animals↗
PubMedDate not supplied

[Magnetic susceptibility of rhodopsin molecules].

It has been calculated that if rhodopsin molecules are associated in photoreceptor membranes they have such a high diamagnetic susceptibility anisotropy that it manifests itself macroscopically in the magnetic field in the order of magnitude of 0.1 kG (8 . 10(3) A/m), but the velocity of this orientation is very low. Thus the interaction with the magnetic field might be limited by kinetics. Malignant transformation is as a rule accompanied by changes in 1) the properties of membrane proteins, 2) their orientation in the membrane, 3) the physical state of lipids in which the membrane proteins are located. Under definite conditions these changes can lead to selective effects of the magnetic fields on the growth of cancer cells in vitro and in vivo (see ref. 2). It is also suggested from thermodynamic considerations that the magnetic anisotropy of biological material (membrane proteins, collagenous structures, muscle and chromatin fibres) might be one of the bases of other biological effects of magnetic fields.

Animals↗
PubMedDate not supplied

Comparative investigation of rate of sedimentation of DNA from human fibroblasts and tumor cells of HeLa line before and after moderate heating.

Changes in DNA after heating of human cells at 43.5 and 44 degrees C were found for the first time by means of sedimentation in an alkaline sucrose gradient. These changes are probably mainly determined by three processes: the appearance in DNA of alkali-labile bonds, the formation of stable DNA--protein complexes, and changes in the superstructure of the DNA, in particular partial unfolding of the nucleosomes. The existence of a mechanism for nonexcision repair of thermal lesions in DNA by an enzyme ("repurinase") catalyzing the formation of a glycoside bond between the base of a purine precursor of DNA and the deoxyribose residue of an apurine component is suggested.

Adult↗