Mathematical model for satellite associations of human acrocentric chromosomes.

Short arms, satellite stalks and satellites of human acrocentric chromosomes (13, 14, 15, 21 and 22) represent heterochromatic regions. Enforced by mutual attraction of heterochromatic regions, the short arms of acrocentric chromosomes come close to each other and compose associations. The associations of human acrocentric chromosomes cause nucleolus formation, undergo age-related changes, account for elevated incidence of chromosome rearrangements and, consequently, can cause chromosome diseases.

[Variability of radiation-induced adaptive response in old age individuals and their correction by Peptide bioregulator -Livagen].

Effect of aging on adaptive response of cellular systems to low (stimulated) dozes of gamma-rays (0, 2 and 0, 5 Gy) and to disturbing dozes of radiation (1 and 2 Gy) has been investigated. PHA-stimulated cells were from 72-86 year-old individuals; control - 30-40 year-old individuals. The potentialities of induction of adaptive response in cells exposed to previously irradiated by stimulating dozes of gamma-rays with subsequent damaging effect of copper chloride (10(-3)M) has been investigated.

Anti-aging peptide bioregulators induce reactivation of chromatin.

The effect of synthetic peptide bioregulators (Epitalon, Livagen and Vilon) on structural and facultative heterochromatin of cultivated lymphocytes have been studied among old (75-88yr.) people. The data obtained indicate that epitalon, livagen and vilon: 1) activate synthetic processes, caused by reactivation of ribosomal genes as a result of deheterochromatinization (decondensation) of nucleolus organizer regions; 2) induce unrolling (deheterochromatinization) of total heterochromatin; 3) release genes repressed by heterochromatinization (condensation) of euchromatic regions forming facultative heterochromatin; 4) epitalon and livagen induce deheterochromatinization (decondensation) of pericentromeric structural heterochromatin of the chromosomes1 and 9.

Bioregulator Vilon-induced reactivation of chromatin in cultured lymphocytes from old people.

The effect of the synthetic peptide bioregulator Vilon on structural and facultative heterochromatin of cultured lymphocytes from old people has been studied. The data obtained indicate that Vilon (a) induces unrolling (deheterochromatinization) of total heterochromatin; (b) activates synthetic processes caused by the reactivation of ribosomal genes as a result of deheterochromatinization of nucleolus organizer regions; (c) releases the genes repressed due to the condensation of euchromatic regions forming facultative heterochromatin; (d) does not induce decondensation of pericentromeric structural heterochromatin. Our results indicate that Vilon causes progressive activation (deheterochromatinization) of the facultative heterochromatin with increased aging.