[Influence of radiation on survivability, behavior and neurochemical correlates of rats].

The aim of the work was to study the dependence of individual radiosensitivity of white and black rats on radiation. The rats under study were derived from a cross between black and white rats and called Ratus Ratus-Georgia. Comparative radiosensitivity of white (Wistar) and black rats was studied at a total exposure with sublethal and lethal doses (5, 7 and 9 Gy).

Physical predictors, behavioural/emotional attributes and neurochemical determinants of dominant behaviour.

Significant differences in physical and behavioural/emotional/cognitive predictors and attributes, as well as of neurochemical inducers of behaviour, between dominant and subordinate animals are discussed. It is still unknown whether these factors are the causes of differences between dominants and subordinates, or vice versa whether the differences between dominants and subordinates are the origin of differences in these factors. The possibility is discussed that no differences exist among juveniles in the concentrations of neurochemical agents (known in the literature as determinants of dominance) between the brains of future dominants and future subordinates.

[New class of RNA and centrosomal hypothesis of cell aging].

The recent discovery of a new class of RNA in a centrosome may be an indirect evidence of the centrosomal hypothesis of cellular ageing and differentiation. The presence of a reverse transcriptase domain in this class of RNA, together with its specificity to this organelle, makes the centrosome a place of information memorizing and reproduction. This feature of centrosome is one of the main points of centrosomal hypothesis of cell aging and differentiation.

RNA in centrosomes: structure and possible functions.

A novel RNA was detected in the centrosomes of Spisula solidissima mollusk oocytes in 2006. This RNA was named centrosomal RNA (cnRNA); five different cnRNAs were described. During the sequencing of the first transcript, cnRNA 11, it was discovered that the transcript contained a conserved structure--a reverse transcriptase domain.

[A new model of depression induced by psychogenenic stress].

A new depression model has been obtained, based on use of stressors of the psychogenic nature. The laboratory rats in a special stress-camera turned out to be unable to induce the bilateral reaction of active avoidance, with subsequently led to formation of depression in the animals. Analysis of the tests sensitive to depression--a forceful swimming and a hanging by tail as well as of dynamics of the animals' body mass and of the behavior on the whole confirms development of their depression.

Testosterone dynamics during encounter: role of emotional factors.

This study attempts to develop a new theory to explain the varying dynamics of testosterone levels in dominant (winners) and subordinate (losers) males, both pre- and post-encounter. The crux of our new theory consists of the following four theses: (1) the strengthening of testosterone synthesis is a result of not only the existence of challenges, but also of a positive mood before an encounter that is associated with the anticipation of a victory; (2) in situations where the anticipation of victory is present but the positive mood is absent, no rise in testosterone levels will occur; (3) testosterone acts as a "pleasure" hormone and usually releases in situations where the individual achieves or anticipates possible satisfaction; (4) an increased release of testosterone to the blood not only decreases anxiety but also elevates the mood, which increases animal's/human's assertiveness and consequently aggressiveness.

The role of androgens in regulating emotional state and aggressive behavior.

This manuscript attempts to develop a new theory to explain both the pre- and post-encounter increase in testosterone levels and the varying dynamics of androgen levels in dominant and subordinate males. The new theory includes the following hypotheses: (i) The pre-encounter increase in testosterone levels is a result of the excitement that is caused by the anticipation of victory. Individuals who do not experience this kind of emotion before the encounter usually do not demonstrate an increased secretion of androgens.

Discovery of centrosomal RNA and centrosomal hypothesis of cellular ageing and differentiation.

In 2006, a group of scientists studying centrosomes of Spisula solidissima mollusc oocytes under the leadership of Alliegro (Alliegro, M.C.; Alliegro, M.

[Chronic psychogenic stress as a factor of formation depressive behavior in rats].

The problem of adequate animal model of depression still remains. In our experiments depression-like condition on white rats were reached by the chronic stressors of psychogenic nature. Stress was carried out in a modified shuttle chamber of active avoidance.

[Study of self-regulating behavior at different stages of psychogenic stress before the formation of depressive-like state in rats].

During last decades abnormalities of neuro-psychic sphere have become a topic of great interest. Among them an important place takes depression. Psychogenic factors are commonly the most frequent cause of depressive condition, and till now the study of so-called transitional period (from the beginning of stressor action till the formation of depressive state) continues to be an actual task of scientific research.

Possible relation of plasma testosterone level to aggressive behavior of male prisoners.

Analysis of testosterone concentration in the blood and urine concentration of norepinephrine and epinephrine showed that testosterone level in aggressive prisoners was higher than in moderately aggressive prisoners, although both concentrations were near the low boundary of normal. The level of norepinephrine was also higher in aggressive prisoners than in moderately aggressive jailed inmates. These data and published reports attest to pronounced role of norepinephrine in the formation the aggressive behavior.

Gerontology research in Georgia.

Gerontology research carried out in different scientific centers of Georgia follows the basic directions of most work in this field: epidemiology, investigation of the mechanisms of aging, and finding ways to prevent senile pathologies and to prolong life. The genealogy and epidemiology of long-living peaple have been studied in areas with high occurrence of these people by considering the sex ratio and social status of the long-living, the influence of environmental factors, and the development of senile pathologies. According to the centrosome (centriole) model of aging, the centrosomes and the cytoskeleton, important structures in cellular differentiation and morphogenesis, may be involved in the initiation of the replication senescence mechanism.

Centriole, differentiation, and senescence.

Irreversible differentiation (change of morphogenetic status) and programmed death (apoptosis) are observed only in somatic cells, and cell division is the only way by which the morphogenetic status of the offspring cells may be modified. It is known that there is a fixed limit to the number of possible cell divisions, the so-called Hayflick limit. Existing links between cell division, differentiation, and apoptosis make it possible to conclude that all of these processes could be controlled by a single self-reproducing structure.

Interhemispheric transfer of kinesthetic information and line bisection task performance in patient with callosal agenesis.

Patient G.J., male, 7 yrs, with callosal agenesis, was found perfectly able to cross-replicate hand postures in right-to left and left-to-right directions.

[Small sample assessment method for a bio-medical research].

A new method of small sample assessment is suggested. It is based on combining of different variational series into a single one. Performing combination procedure, common biological laws and logical consideration should be taken into account.

Stress-induced increase of testosterone: contributions of social status and sympathetic reactivity.

The vast number of studies in both human and animals confirm the inhibiting role of different stressors in the hormonal function of the testicles, decreasing the testosterone (T) level in the blood. However, there also are data suggesting that stress does not invariably inhibit the activity of the testicles. Moreover, the T level in blood may be increased at initial stages of acute stress.

[Centrosomal hypothesis of cellular aging and differentiation].

The article is dedicated to analysis of centrosomal hypothesis of cellular aging in the light of new data concerning existence of centrosomal RNA, and also in the light of the role of maternal and daughter centrosomes in processes of asymmetric division of stem cells. It is supposed that these data confirm the central role of centrosomes in aging and cellular differentiation. Additional arguments concerning conceptual consistency of telomeric and centrosomal hypothesis of cellular aging are presented.

[Aggressive behavior, its adaptive function and mechanisms of development of psychosomatic disorders and diseases of adaptation].

A correlation between physiologic and behavioral responses to emotional stress and agonistic conflict (triad model), as well as ideas of autonomic-humoral support of subsequent activity suggest that motor activity and situational aggressive behavior are essential final stages of stress reaction and, therefore, mechanisms of adaptation. Failure in final the stage of adaptive response causes mobilization changes to be directed against the host organism itself. This phenomenon forms the basis for psychosomatic disorders.

Centriolar mechanisms of differentiation and replicative aging of higher animal cells.

The centrosome (centriole) and the cytoskeleton produced by it are structures, which probably determine differentiation, morphogenesis, and switching on the mechanism of replicative aging in all somatic cells of multicellular animals. The mechanism of such programming of the events seems to include cytoskeleton influences and small RNAs related to the centrosome. 1) If these functions are really related with centrioles, the multicellular organism's cells which: a) initially lack centrioles (e.

Potential role of centrioles in determining the morphogenetic status of animal somatic cells.

Irreversible differentiation (change of morphogenetic status) and programmed death (apoptosis) are observed only in somatic cells. Cell division is the only way by which the morphogenetic status of the offspring cells may be modified. It is known that there is a fixed limit to the number of possible cell divisions, the so-called 'Hayflick limit'.