Effects of Screen Time and Season on Cardiovascular System Indicators in Primary Schoolchildren.

Indicators of the cardiovascular system, including heart rate (HR) and blood pressure (BP) variability parameters, were analyzed in primary school students with different computer screen times. The study included 4084 students of grades 1-4 (age 7-12 years) from 66 Moscow schools. The screen time at school and out of school was assessed by teachers, based on the national Sanitary Rules and Regulations: 0, no screen time; 1, screen time matching hygienic standards; 2, screen time at least twice greater than recommended. Physiological examinations were carried out by spiroarteriocardiorhythmography with a face mask, the conditions corresponding to the functional stress test (mild hypercapnia/hypoxia). Testing took place in spring and autumn (independent samples). Statistical data processing was performed using nonparametric criteria. It was revealed that the introduction of computer technologies in school lessons within the limits of hygienic standards was accompanied by an increase, within the normal range, of systolic BP in girls at the end of grade 2 and 4 and in boys at the beginning and end of grade 4. Screen time at least twice higher than the hygienic standard did not have an additional effect on BP, but provoked shifts in the function of autonomic regulation. Boys were more sensitive to the influence of this environmental factor. Their pattern of seasonal variability in total power (TP) of the HR variability spectrum was reversed compared to that of children who did not use computers at school; i.e., higher TP values were observed in spring. In grade 4, the process was accompanied by an increase in spontaneous arterial baroreflex sensitivity and a decrease in the relative power of the LF range in the variability spectrum of systolic BP. The changes were assumed to reflect the adaptive response to changes in educational environment.

[Epigenetic regulation of adaptogenesis by pathology and aging.]

The organism adaptive possibilities by pathology and aging are discussed in account of the epigenetic. The organism adaptation to inner and external factors is carried out by organism unite humoral protective system, inclusive hypothalamus-hypophysis-pineal and hypothalamus-hypophysis-thymus axises. AEDG, AEDP, EDR, KED, EW, KE short peptides are the epigenetic regulators of gene expression and protein synthesis, which can be involve to the adaptation by stress and in the activation of hypothalamus-hypophysis-pineal and hypothalamus-hypophysis-thymus axises. These short peptides regulate the synthesis of proteins of heat shock, stress-protective proteins, cytocines, fibrinolysis and hemostasis factors and can participate in primary and tardive epigenetic regulation of adaptive response by stress, pathology and aging. The early functional diagnostic of element disturbances of organism unite humoral protective system by age-associative pathology can be usefull for the detection of deficient synchronization of epigenetic mechanisms, by wich the depletion and decrease of organism reserve possibilities occurs. The use of peptide can grade the adaptive syndrome manifestation by the stress and age pathology.

[Possible mechanism of the selective action of the inhibitors of glycolysis in the endothelial cells and the human carcinoma cells in the culture].

It is known that the production of energy and synthesis of macromolecules in cancer cells depend on the glucose metabolism to a greater extent than in non-tumor. In this paper we carry out a comparative study of the effectiveness of the two modifiers glycolysis 2 - D-deoxyglucose (2-DG) and dichloroacetate (DCA) in the induction of the cell death, changes in the cell cycle progression and in the alteration of the intracellular ROS levels in endothelial cells (line ECV304) and human carcinoma cells (line HeLa G-63) in order to identify cause-effect relations between these events. It has been shown that inhibition of the various stages of the glycolysis result in blocking cells in C2/M phase of the cell cycle and the induction of the cell death. This effect was record for HeLa G-63 cells only. DCA is inhibitor of the pyruvate dehydrogenase kinase and 2-DG is inhibitor of the glucose transport and glycosylation induced selective dose-dependent cytotoxic effect in HeLa G-63 cells. The increase of intracellular levels of the oxygen radicals induced by DCA in the cells HeLa G-63 suggests that the cytotoxic effect of the DCA is mediated by activation of the mitochondrial functions. The cytotoxic effect of 2-DG depend on the level of glucose in the culture medium, therefore we suggest that not only the oxidative stress, but and the energy depletion involved in selective response of the cancer cells on the actions of the inhibitors of glycolysis.

[Assessing of the role superoxide, nitric oxide and redox metals in cytotoxic effect of the H2O2 and amyloid-beta-protein].

On the cells of neuroendocrine tumor of rats (line PC12) in culture was estimating of the governing mechanisms of the cytotoxicity of the oxidative stress and the role of the amyloids in increasing this stress. Using flowcytometric assessment of the cytotoxicity H2O2 and fragment beta-amyloid (Abeta) peptide (25-35) has been shown the dose-dependent increasing of the quote of the cells with DNA content < 2c. Isoeffective consentrations were 1 MM H2O2 and 5 MkappaM Abeta. The cytotoxicity H2O2 and A were accompanig with the increasing of the intracellular level of O2-. The treatment of the cells GSNO (donor of NO) and o-phenantrolin (chelators of Fe ions) significantly decreased the intracellular level of O2- as well as the cytotoxicity H2O2 and Abeta. Thus, in direct experiments has been shown of the part amyloids in the increasing of the oxidative stress and participation of the reactive oxide radicals in the cytotoxic effect of the Abeta. The addition argument which confirmed contribution of the oxidative stress in the cytotoxic effect of the Abeta was the similarity of the cellular response on the action of the oxidative agent - H2O2 and Abeta.

Changes in nitric oxide and superoxide levels in human endotheliocytes and carcinoma cells after exposure to low-dose ionizing radiation.

The exposure of HeLa G63 and ECV-304 cells to γ-rays of (137)Cs as well as ß-particles of (3)H(2)O and (3)H-thymidine induced changes in redox status of not only irradiated cells, but also their progeny. Increased intracellular levels of nitric oxide (NO) were observed only in HeLa G63 cells and persisted over three cell generations; ß-particles from (3)H(2)O were most efficient. Intracellular superoxide (O(2)(-)) level had similar dynamics in both cell lines. Intracellular O(2)(-) level decreased immediately after irradiation, but then increased and significantly surpassed the control level. These changes in the intracellular level of O(2)(-) were accompanied by decondensation of nuclear chromatin. Increased level of free radicals in the progeny of irradiated cells and changes in chromatin conformation and the absence of correlation between radiation-induced structural damage to chromosomes and intracellular level of free radicals suggest participation of epigenetic mechanisms of inheritance.

[Immediate and delayed effects of low doses of beta-radiation in mammalian cells in culture].

We have carried out the comparative examination into the efficacy of induction of NO and superoxide anion by incorporated and unincorporated sources of ionizing radiation in endotheliocytes (line ECV 304) and carcinoma cells (line HeLa G63) expressing various forms of NO-synthases. The increased intracellular nitric oxide levels were observed after exposure of the cells to beta-particles of 3H-thymidine and 3H2O, as well as to gamma-rays of 137Cs in HeLa G63 cells expressing the inducible forms of NO-synthases. A higher incidence of the intracellular NO level was observed after exposure to beta-particles of 3H2O than to beta-particles of 3H-thymidine or gamma-rays of 137Cs even though 3H-thymidine and gamma-rays elicited more chromosomal damages. Modification of the intracellular superoxide level was shown to have a similar dynamics of the changes in time for the both cellular lines. Shortly after irradiation, the intracellular superoxide level was lower than in non-irradiated cells, and then it became higher than the control level. The increased intracellular superoxide and NO levels were observed after exposure of the cells to beta-particles of 3H-thymidine and 3H2O, as well as to gamma-rays of 137Cs in the progeny of irradiated cells. Modification of the intracellular superoxide level was accompanied by decondensation of the cellular chromatin. A higher intracellular free radical level in the progeny of irradiated cells along with decondensation of cellular chromatin, as well as the absence of correlation between a radiation-induced structural damage of chromosomes and intracellular free radical level allow us to speculate in favor of the participation of epigenetic inheritance mechanisms.

Modification of intracellular level of free radicals and apoptosis in cultured human endotheliocytes and carcinoma cells.

The intracellular levels of superoxide O(2)(-)and nitric oxide NO were directly measured under intravital conditions in cultured human endotheliocytes ECV 304 and carcinoma cells HeLa G-63. Comparative analysis of changes in the intracellular levels of superoxide and NO induced by ascorbic acid revealed a negative correlation between NO and O(2)(-)levels, whose strength depended on concentration of the acid. In pharmacological concentrations, ascorbic acid induced apoptotic death of carcinoma cells, but did not trigger apoptosis of endotheliocytes. The study demonstrated a possible way of cytotoxic action of ascorbic acid in pharmacological concentrations.

Dynamics of intracellular superoxide and NO content in human endotheliocytes and carcinoma cells after treatment with NO synthase inhibitors.

The dynamics of intracellular levels of superoxide and NO after cell treatment with NO synthase inhibitors were studied in human cells expressing various NOS isoforms: endotheliocytes and ECV-304 (eNOS) and carcinoma cells and HeLa-G63 (iNOS). Cytometric analysis of changes in the cell fluorescence intensity was carried out using superoxide and NO fluorescent indicators (dihydroethidene and DAF-2-DA, respectively). Intracellular levels of superoxide decreased in HeLa-G63 and ECV-304 cells after their incubation in medium with aminoguanidine, L-NAME, and D-NAME. Intracellular NO level decreased only in HeLa-G63 cells after incubation in medium with aminoguanidine and L-NAME, but not D-NAME. The level of NO returned to normal after 7-h culturing in inhibitor-free medium, while the level of superoxide increased and remained high throughout 3 generations. Incubation of cells with D-NAME did not increase the intracellular level of superoxide. Presumably, high prolonged generation of superoxide is a delayed result of inhibition of NO synthesis in HeLa-G63 cells.

Cytogenic abnormalities in buccal cells during spinal deformities in children.

Evaluation of the incidence of nucleus abnormalities in buccal epithelium allows detecting the presence and intensity of the effect of various ecological conditions and pathologies of the musculoskeletal system. Two coefficients were used: mean number of NA per cell and ratio of cells with karyolysis to the total number of cells with NA. Coefficient of karyolysis decreases with increasing anthropogenic load In pupils of a special school in Moscow these coefficients were similar. Analysis of coefficients showed that karyolysis coefficient was reduced in mothers of children with spinal deformities.

Intracellular NO concentration and its changes in carcinoma cells and cultured human endotheliocytes under the influence of inhibitors and inductors of nitric oxide synthases.

We carried out cytophotometric evaluation of NO content in cells expressing various types of NO synthases. Endogenous production of NO can be modified by NO synthase inductors and inhibitors.

[The blocking of the proliferation of the human endothelial cells in culture by beta-irradiation from internal and external sources of the radiation. S-block is induced by the 3H2O beta-particles].

Recently we shown that low doses (0.12-0.46 Gy) of (methyl-3H)-thymidine incorporated into human endothelial cells induce the accumulation cells in G2-phase of the cell cycle. The temperate doses of (1-6 Gy) gamma-rays 137Cs were less effective in the induction of the G2-block estimated by flow cytometry analysis of DNA content and in the induction of the chromosome aberrations (bridges and fragments in anaphase). The aim of this study was the comparative investigation of efficiency of beta-rays emitted 3H from 3H-thymidine and 3H2O by several of the cellular parameters. Here we shown that at the equal conditions of the incubation of the cells in medium with 3H2O induced the accumulation cells in S-phase without decreasing of the mitotic activity and without increasing of the chromosome aberrations level. Unlike from 3H2O the incubation of the cells with 3H-thymidine induced the accumulation cells in G2-phase with decrease of the mitotic activity and with increase of the chromosome aberrations level. Concurrent treatment cells with 3H-thymidine and thymidine abrogate these cellular effects of the 3H-thymidine. Inhibitor ATM-kinase caffeine abrogate as G2-block as S-phase block. These results suggest that the low-dose beta-radiation activates S-phase and G2-phase checkpoints requiring ATM-mediated signal transduction pathway. The factors, which impact on the efficiency of the internal and of the external sources of the irradiation, depend on theirs disposition in relation to radiosensitive target--DNA was discussed.

[Internal and external sources of the radiation induce the blocking of the proliferation of the human endothelial cells in culture. G2-block is induced by beta-particle 3H-thymidine and gamma-rays 137Cs].

We found that low doses (0.12-0.46Gy) of (methyl-) 3H-thymidine incorporated into human endothelial cells induce the accumulation cells in G2-phase of the cell cycle. Temperate doses of (1-6 Gy) gamma-rays 137Cs were less effective in the G2-block estimated by flow cytometry analysis of DNA content. Furthermore, the induced the high level of the chromosome aberrations (bridges and fragments in anaphases). 1Gy of gamma-ray 137Cs and 0.005 Gy of beta-rays induced the same per cent of the aberrant anaphases. Apparently, that the damages of the cellular hereditary structures are responsible for the blocking of the cellular proliferation in G2-phase. We suggest, that the disposition 3H-thymidine into radiosensitive target (DNA) defines the high cytotoxic of the beta-rays.

[Use of a cytogenetic method for buccal epithelium study, and a method of laser correlation spectrometry for health disturbances monitoring in children].

Buccal epithelium cytogenetic disturbances were studied in schoolchildren from Moscow schools, a country school (Novgorod region) and a Moscow boarding school for chindren with musculoskeletal diseases (scoliosis and kyphosis). The minimal mean frequency of cells with karyorrhexis were revealed in children from an ecologically pure Novgorod region. Moscow schoolchildren demonstrated more than 13-fold higher level of this parameter. Children with spinal deformities had an intermediate frequency. Cells with karyolysis minimal mean frequency were observed in Moscow pupils. Children from Novgorod demonstrated a statistically valid higher level of this parameter, and the maximum was reached in Moscow boarding school. No difference between these groups was revealed in a study of the mean frequency of binucleated cells, cells with pyknosis, cells with micronuclei, or "broken eggs" incidence. Laser correlation spectrometry (LCS) method was used for parallel studies. It was shown that the distribution of spectra in Moscow pupils and in children with spinal deformities differs from that in children living in ecologically pure region. Normal spectra prevailed in pupils of country school, who demonstrated, in addition, high levels of anabolic and low levels of catabolic type metabolism. The examined Moscow schoolchildren demonstrated almost the same incidence of normal spectra. They differed from the country children by statistically valid reduction of anabolic type spectra, and by increased levels of catabolic type spectra. Young patients with spinal deformities demonstrated the maximum incidence of catabolic type spectra. The authors suggest the availability of a qualitative correlation between both the monitoring methods used in this study. It was shown that children living in unfavorable conditions and patients with musculoskeletal diseases manifested an enhanced incidence of buccal epithelium cells with karyorrhexis and karyolysis, as well as higher levels of catabolic type spectra accompanied by reduction of normal and anabolic type spectra.

[Modification of cellular radiosensitivity by NO-synthase inhibitors].

We recently reported that the treatment of V-79 and HeLa cells with nitric oxide synthase (NOS) inhibitor N-nitro-L-arginine methyl ester (L-NAME) significantly reduced the level of the radiation-induced unstable chromosome aberrations. The stereoisomer D-NAME had no effect. We suggest that the radioprotective effect of L-NAME resulted from the action on the generation reactive radicals due to the inhibition of the NOS-activity. We tested this suggestion on the NO-resistant (ECV-304) and NO-sensitive (HeLa) cells, which were treated with L-NAME or aminoguanidine or D-NAME or cysteamine before gamma-irradiation. There are no significantly differences in radiosensitivity between these cells estimated after exposure by gamma-rays with different doses. However, the radioprotective effect of the NOS-inhibitors manifested only for HeLa. D-NAME had no radioprotective effect neither HeLa nor ECV-304. In contrast NOS-inhibitors, cysteamine treatment EVC-304 reduced the radiation-induced level chromosome aberrations almost twofold. The different mechanisms of the modification of cellular radiosensitivity are discussed.

[Molecular reasons for the regulation of the enzymatic activity of bovine pancreatic deoxyribonuclease I as studied by dynamic light scattering and fluorescent spectroscopy].

The effect of catalytic bivalent and inhibitory monovalent cations on the interactions of bovine pancreatic deoxyribonuclease I with the circle single-stranded DNA of M13 phase was studied. It was found that monovalent cations affect the site of binding to DNA and the active center of the enzyme; in their presence, a break of the formation of the enzyme-substrate complex occurs. The results provide evidence that conformational changes of the protein molecule in all cases are more substantial that it could be expected from X-ray data published earlier.

[Polysystemic assessment of the state of sanogenesis in workers employed in nuclear fuel plants. The analysis of functional state of cardiovascular, respiratory, and psychomotor systems]. / Polisistemnaia otsenka sostoianiia sanogeneza rabotnikov predpriiatiia iaderno-toplivnogo tsikla.Analiz funktsional'nogo sostoianiia serdechno-sosudistoi, dykhatel'noi i psikhomotornoi sistem.

The state of the cardiovascular, respiratory, and psychomotor systems of workers employed in nuclear fuel plant was evaluated using a computer-assisted laboratory complex. It was found that neuroendocrine regulation of the peripheral circulation and muscular activity responsible for fine motions are most vulnerable to industrial hazardous factors.

[The cytogenetic damage, radiosensitivity and adaptive response in children living in the different districts of Moscow]. / Tsitogeneticheskie povrezhdeniia, radiochuvstvitel'nost' i adaptivnyi otvet u detei, prozhivaiushchikh v raznykh raionakh Moskvy.

The spontaneous level of blood lymphocytes with micronuclei (MN), the sensitivity to 1.0 Gy irradiation and adaptive response (AR) after adaptive irradiation with a dose of 0.05 Gy 5 hr later have been studied in children population living in different districts of Moscow. It was shown that spontaneous frequency of cells with MN, the sensitivity to 1.0 Gy acute irradiation and the AR manifestation have significant differences in samples taken from children living in different districts. The individual variability is significant also. In each group of children the individuals with the enhanced radiosensitivity after adaptive irradiation have been observed. In conformance with the data of radioecological inspection the radiation situation in different Moscow districts is quite safe on overage but in some districts the spontaneous level of lymphocytes with MN, and radiosensitivity after 0.05 Gy irradiation were enhanced, the AR was not found.

[NO-dependent pathway of the modifying of the cellular sensitivity to gamma- and neutron irradiation]. / NO-zavisimyi put' modifikatsii kletochnoi chuvstvel'nosti k deistviiu gamma- i neitronnogo izlucheniia.

The modifying effect of L-NAME, the NO-synthase inhibitor and D-NAME, the inactive enantiomer was investigated in human carcinoma cells (HeLa) and Chinese hamster fibroblasts (V-79) exposed to different doses of gamma-rays and 0.85 MeV neutrons. We estimated the level of the chromosome aberrations manifested as the bridges and fragments in anaphases. Radioprotective effect of L-NAME showed the inverse dependence on the exposure dose and at low doses (1 Gy) it was higher in the V-79 cells, than in the HeLa cells. However, at high doses (3, 4, 6 Gy) the efficiency of L-NAME for these cellular lines was almost equal (DFR = 2). The modifying effect of L-NAME was almost equal for gamma-irradiation and neutrons, although the exposure of V-79 cells to neutrons induced more the asymmetric chromosome aberrations (RBE = 4). The D-NAME had no effect on the level of the radiation-induced chromosome aberrations, although D-NAME treatment of cells increased the chromatin condensation, as well as L-NAME. The counteractive condensation does not play the major role in the radioprotective effect of L-NAME. We suggest that the radioprotective effect of L-NAME resulted from the action on the generation reactive radicals due to the inhibition of the inducible NO-synthase.

[Laser-correlation spectroscopy of the lacrimal fluid in the evaluation of the semiotic nature of postoperative inflammatory reaction and the degree of its severity in patients with diabetes mellitus after intraocular lens implantation]. / Lazernaia korreliatsionnaia spektroskopiia sleznoi zhidkosti v otsenke semioticheskogo kharaktera posleoperatsionnoi vospalitel'noi reaktsii i stepeni ee tiazhesti u bol'nykh sakharnym diabetom s implantatsiei intraokuliarnykh linz.

Lavages of the lacrimal fluid were examined, before operation and immediately after operation, in 47 patients with diabetes mellitus and with pseudophakia in order to define the possibilities of the method of laser-correlation spectroscopy (LCS) in evaluating the semiotic nature and a severity degree of postoperative inflammation. It was found that, when the subjective symptomatology of inflammation in the LCS spectrums intensified, there was a higher contribution to the light dissemination of particles with a hydrodynamic diameter of 600 nm and more (i.e. of heavy lipoprotein complexes and of immune complexes), which were determined after a computer-based processing as a condition of primary intoxication and of immune shifts. The LCS results objectively confirmed that the degree of inflammatory changes during the early postoperative period was reliably higher in patients with a level of glycolyzed hemoglobin exceeding 9% versus patients with the above parameter being below 9%.

New approach to objective diagnostics of polyfunctional disorders of the neuromuscular regulation in children with various forms of spine deformities.

A combination of two methodical approaches (parallel evaluation of the psychomotor function and metabolic shifts) was used in examination of children with scoliosis. We evaluated adaptation of children at the certain stage of the disease for prediction of its further course and correction of the treatment.