[Ultrasound duplex scanning of head and neck vessels with the aim of preoperational preparation of the patients with inherent microtia of the III degree].

For surgical treatment of patients with inherent microtia of the III degree we use one stage method of otoplasty with silicone implant and parietotemporal fascial flap. In order to receive most full picture of the status of superficial temporal artery and its branches the additional diagnostic study is necessary. Method of ultrasound duplex scanning let to study any vessel in real time regimen under monitor screen control. Received by us results of ultrasound duplex scanning of superficial temporal artery branches in patients with inherent microtia of the III degree let us to conclude about the status of the vessel wall, to determine diameter and vessel occlusion, to evaluate and measure blood flow parameters. It is diagnostically necessary criteria for answering the question about flap vitality and in such a way let to avoid possible complications.

[Structural and functional changing induced by exposure to adaptive doses of X-rays in the human lymphocytes both normal and defective by reparation of DNA double strands breaks]. / Strukturnye i funktsional'nye preobrazovaniia, indutsiruemye X-radiatsiei v diapazone adaptiruiushchikh doz, v normal'nykh i defektnykh do reparatsiidvoinykh razryvov DNK G0-limfotsitakh cheloveka.

In the present work it is shown that the phenomenon of interphase chromosome centromeric region displacement, earlier revealed by the authors, is not realized in G0-lymphocytes with heterozygous BRCA1/2 gene mutations. The role of these genes in DNA double strand break (DSB) reparation is known. It is concluded that chromosome locus displacement is necessary for DSB repair, at least in the process of homologous recombination. In accordance with our data, some feature (pericentromeric cluster disintegration and displacement, the nucleus size increasing) characteristic for S- and G0-lymphocytes are observed in normal G0-lymphocytes treated with 3 and 10 cGy. However, the size of nucleus in G0-lymphocytes is restored through 6 hours after irradiation in opposite to the process in dividing cells. It was proposed that some typical for resting cell functions of G0-lymphocytes after inducing by adaptive doze of radiation are stopped as similarly as after stimulation of cells. Interestingly, that the process of the induced chromosome loci displacement is correlated with the decreasing of DNA reparation possibilities under UV-irradiation. The induced apoptosis level also decreases when chromosome loci are displaced. The possible mechanisms of the revealed phenomenon are discussed. This research supported by RFBR grant (No. 01-04-49180).

[Theoretical and experimental approach to the problem of changes in functional capability of cells under the effects of adaptive doses of ionizing radiation]. / Teoreticheskie i éksperimental'nye podkhody k probleme indutsiruemykh adaptiruiushchimi dozami ioniziruiushchei radiatsii izmenenii funktsional'nykh vozmozhnostei kletok.

It is concluded that a dose range from background dose to several cGy may be separated into two parts: a) first--the interval of small doses limited from above by D* which is determined from (1 g (D*/Doc)) < -0.51 g (n/2)), where Dse is an average dose of a single event, n--quantity of irradiated cells; in this interval only one track intersects a sensitive volume; b) second--the interval of low doses, in which in average one track intersects the volume and which is ranged from top D* to bottom Dse. Because events in this region qualitatively are similar to background events, cells in the dose range b) may be adapted to the influence of radiation. The first stage of the adaptive response of cells is associated with chromosome loci (centromere) movement in a cell nucleus and as we suggest the latter is the fundamental mechanism for repairing DSB DNA and switching of gene transcription. Because the movement of chromosome loci both in the resting cells under the adapting doses and in the normal dividing cells is much the same (but the latter lose their function characteristic for differentiated resting cells), it could be assumed that the resting cells under the adapting doses also lose their functional parameters. Under chronic exposure to low doses this functional changes can be principal for discussion on the influence of low doses on health.

[Potential relationship between mutation process induced by low doses of ionizing radiation, and positional dynamics of chromosomes in nuclei of eukaryotic cells]. / O vozmozhnoi sviazi mutatsionnogo protsessa, indutsirovannogo malymi dozami ioniziruiushchei radiatsii, i pozitsionnoi dinamikoi khromosom v iadrakh kletok éukariot.

The mutation process has many stages. The information presented in this article suggest that a cell exposed to low LET radiation in the low-dose range (up to 1 cGy) must almost completely repair all spontaneous and radiation-induced DNA lesions. But reparation of DNA double-stranded breaks (DSB), which are the basis of genome instability has peculiarity. We have shown that the mechanisms of action of low doses (which initiate natural antimutagenic reactions of resting cells--an adaptive response) are associated with chromosome loci (centromere) movement in a cell nucleus. We suggest that the movement of chromosome loci in cell nucleus is the fundamental mechanism for repair of DSB and switching of the transcription of gene (it is known that in case of lymphoid cells Ikaros-complexes repressor is colocolizated with centromere loci); in particular, of nucleolar transcription activities because the latter is dependent on centromere arrangement. Because the movement of chromosome loci in both the mitotic cycle and under adapting dose on resting cells is much the same it could be assumed that in latter case the cells also lose their functional characteristic for differentiated resting cells. Under chronic exposure to low doses the functional changes can be the cause of organic changes if adapting dose affects the sufficient part of the cells. The role of cells of evolutional or ontogenetic reserve in mutation process is considered.

[Use of Regenkur hydrogel in the local treatment of burns]. / Primenenie gidrogelia Regenkura dlia mestnogo lechenia ozhogov.

In local treatment of patients with II-IIIA degree burns with the area of from 1.5 to 20% of body surface, the use of hydrogel on the basis of a polymeric sorbent Regencur contributed to attenuation of pain, 2-fold reduction in number of dressings, creation of favourable conditions for course of the reparative processes in burn wounds.