The delayed effects of high-energy krypton on neurological manifestations, biochemical, hematological and cytogenetic indices were investigated with primates as a model. Several primates developed distinct neurological reactions. Dynamics of several biochemical and hematological indices correlated with the neurological reactions. In this case, some biochemical and hematological indices deviated from the physiological norm. In primates that had no neurological reactions these changes were less evident. The data can be considered as a prerequisite for research and development of a system of protecting cosmonaut's organism against the effects of galactic cosmic radiation.

A study has been conducted of cytogenetic violations that occur in blood lymphocytes of Macaca mulatta monkeys after local exposure of the hippocampal region to accelerated 78Kr ions at a dose of 3 Gy. Analysis revealed a low level of chromosomal aberrations in the control group of monkeys. The number of cells with chromosomal aberrations did not exceed 1.67

Purpose: Characterization of the response of mouse microglia cells of the SIM-A9 line to the γ-irradiation. Material and methods: Irradiation of the cells in suspension was carried out using a GUT-200M installation (cobalt-60 γ-radiation source). The radiosensitivity of cells was assessed by the number of surviving cells and their clonogenic activity. The effect of γ-radiation on the phenotype and expression of colony-stimulating growth factor receptor-1 and of epidermal growth factor, which are required to stimulate microglial cells proliferation, was studied using flow cytometry after staining the cells with appropriate fluorescently labeled CD11b, CD45, TMEM119, CSF-1R и EGFR antibodies. Analysis of the relative expression of mRNA genes for the cytokines IL-1β, IL-6, and TNFα in response to γ-radiation was performed using RT-PCR. Statistical analysis was carried out using Student’s t-test in the Origin program. Results: High radiosensitivity of SIM-A9 cells has been demonstrated. When analyzing the dependence of the clonogenic activity of cells on the radiation dose, it was shown that the D37 value for these cells was equal to 1 Gy. Irradiation caused a cell cycle block in the G0/G1 phase with a decrease in the proportion of cells in the S– and G2/M-phases. The cell death of irradiated SIM-A9 cells occurred by apoptosis. The peculiarity of SIM-A9 cells compared to brain microglia is their phenotype of activated microglia CD11b+/CD45high with an insignificant content of CD11b+/CD45-/low cells and no change in it after irradiation. An increase in the level of mRNA expression of the proinflammatory cytokine genes IL-1β, IL-6 and TNFα in response to γ-irradiation of SIM-A9 cells was shown, which reflects their activation and corresponds to the response of brain microglia cells during total mice irradiation and local cranial irradiation. Conclusion: The obtained patterns indicate the possibility of using the SIM-A cell line in model radiobiological studies, including the study of intercellular interactions of brain cells of different types with microglia cells.

SIM-A9 is a line of spontaneously immortalized mouse microglia cells obtained from newborn C57BL/6 mice’s cerebrum. The aim of this work is to characterize SIM-A9 line by the ratio of cells with the resting and activated microglia phenotype, to analyze the expression of stem/progenitor cell markers CD133 and nestin, growth factors receptors CSF-1R and EGFR, and the karyotype of this line. The light microscopy, immunocytochemistry, flow cytometry and RT/PCR were used to analyze the morphology, phenotype, and gene expression levels of pro-inflammatory cytokines, and the mFISH method was used to analyze the karyotype. It was shown for the first time that SIM-A9 cells express a high level of TSPO protein, CD68, CD11b and CD45 markers on the surface membrane of cells, which corresponds to the phenotype of activated microglia. Despite this, the cells of this line respond with additional activation to LPS stimulation, which leads to an increase in the pro-inflammatory cytokine genes IL-1β, TNFα, IL-6 expression and a high level of active oxygen and nitrogen metabolites formation. It was shown that SIM-A9 cells express stem and progenitor cells markers, CD133+ and nestin, which allows us to consider the cells of this line as early poorly differentiated progenitor cells, despite their phenotype corresponding to activated microglia. It was also found that SIM-A9 cells express receptors of two growth factors CSF-1 and EGF, CSF-1R and EGFR, which indicates the possibility of SIM-A9 cells proliferation stimulation by two alternative mechanisms under the action of the corresponding factors. SIM-A9 cells have a hypotetraploid karyotype with a large number of structural and quantitative chromosome anomalies.

SIM-A9 is a line of spontaneously immortalized mouse microglial cells obtained from the brain of newborn C57BL/6 mice. The purpose of this work is to characterize the microglia of the SIM-A9 mouse line on the basis of the ratio of cells with the phenotype of resting and activated microglia in culture and to analyze the expression of markers of CD133 stem (progenitor) cells and nestin, which are receptors for growth factors CSF-1R and EGFR, as well as to analyze the karyotype of this line. Light microscopy and immunocytochemistry combined with flow cytometry and RT–PCR were used to analyze the morphology, phenotype, and expression level of pro-inflammatory cytokine genes, and the mFISH method was used to analyze the karyotype. It has been shown for the first time that SIM-A9 cells express a high level of TSPO protein and CD68, CD11b, and CD45 high markers on the surface membrane of cells, which corresponds to the phenotype of activated microglia. Despite this, the cells of the line respond with additional activation in response to lipopolysaccharide stimulation, which leads to an increase in the expression of pro-inflammatory cytokine genes IL-1β, TNFα, and IL-6 and the formation of a high level of active oxygen and nitrogen metabolites. SIM-A9 cells were shown to express markers of stem and progenitor cells CD133 + and nestin, which allows us to consider them as early poorly differentiated progenitor cells, despite their phenotype corresponding to activated microglia. It was also found that SIM-A9 cells express receptors of the two growth factors CSF-1 and EGF, CSF-1R and EGFR, which indicates the possibility of stimulation of SIM-A9 cell proliferation by two alternative mechanisms under the action of corresponding factors. SIM-A9 cells have a hypotetraploid karyotype with a large number of structural and quantitative chromosome anomalies.

Abstract-The cultivation of Chinese hamster fibroblasts (line V79) on ion-track membranes of various polyesters has been tested. Light and electron microscopy were used to take photographs of polyester membranes with fibroblasts grown on them, which indicated the attachment and proliferation of cells on ion-track adhesive surfaces. The greatest survival of fibroblasts was observed on ion-track membranes with a pore diameter of up to 0.5 μ. It was shown that the chemical composition of the track membrane affects the survival and proliferation rate of Chinese hamster fibroblasts. Polyethylene terephtalate and polyethylene naphtalate membranes provided the highest percentage of grown colonies and the greatest proliferation rate of cells. Track-etched polyester membranes can be used to create adhesive surfaces for the cultivation of fibroblasts and the production of artificial connective tissue. Key words: ion-track membranes and technologies, tissue engineering, fibroblasts, burn therapy

Currently, one of the rapidly developing applications of polymer matrices, or scaffolds, is tissue engineering. The usage of ion-track technologies to create scaffolds for the cultivation of various cell populations can open up new opportunities in fundamental cell biology and practical regenerative medicine.

The radiobiological effects of accelerated ions with high charge and high energy (HZE) on mammalian cells and their propagation in time are still not sufficiently explained and attract great deal of attention. This work aims to compare the immediate and delayed effects with emphasis on the latter. As shown by our group, the dependence of mutant fraction on expression time after irradiation may have interesting, non-monotonic, character depending on LET (linear energy transfer) of the used heavy ions. We speculate that this phenomenon may occur due to the induced genomic instability. Another area of our research is the study of the DNA structural changes in these mutants induced at different expression times. Chinese hamster V79 cells were irradiated with accelerated ions 11 B, 18 O, 20 Ne, and gamma radiation. The LET was ranging from 0.23 keV/μm of 60 Co gamma rays up to 136 keV/μm of 20 Ne ions. DNA of unique HPRT mutants was isolated, concentration measured, HPRT exons amplified, and analyzed at several different time points, up to about 40 days, after exposure. Over 1200 HPRT mutants were analyzed for deletions of exons and sorted into three main categories: partial deletion, PD—with deletion of one to eight exons; total deletions, TD—with all nine exons deleted; and no deletions—no change in the HPRT structure observed. In general, the number of samples with partial deletion was increasing with LET of the used radiation, suggesting that higher energy deposition to the cell nucleus is more likely to cause larger structural changes. In the case of total deletions, increase in their number with LET was observed up to LET ∼115 keV/μm followed by a sharp decrease. The samples were also analyzed for the distribution of deletions, in particular exons at various expression times, the so-called mutational patterns. Hypothesis of the mechanisms behind observed phenomena is given, and possible implications for further research are discussed.

In a study on primates (Macaca mulatta), neurobiological and radiobiological effects have been studied of the synchronous combined action of 7-day antiorthostatic hypokinesia and exposure of the monkeys' head first to γ-rays during 24 h and then to accelerated 12C ions. The neurobiological effects were evaluated by the cognitive functions which model the basic elements of operator activity and the concentration of monoamines and their metabolites in peripheral blood. The radiobiological effects were evaluated by the chromosomal aberration and DNA double-strand break (DSB) yield in peripheral blood lymphocytes. The results of the cognitive function research show that the typological features of the animals' higher nervous activity are the prevailing factor that determines changes in these functions. The monkey of the strong balanced type effectively retained its cognitive functions after the exposures, while in the weak unbalanced type animals these functions were impaired. These changes went along with a decrease in the concentration of monoamines and their metabolites and an increase in the DNA DSB and chromosomal aberration yield in lymphocytes.

The mutagenic effect of accelerated heavy charged particles on the Chinese hamster V79 cell line is studied. The induction of HPRT mutations in irradiated cells for a long expression time (up to 45 days) after exposure to radiation with different LET are analyzed. The maximum yield of mutant clones is observed at different expression times, depending on the characteristics of ionizing radiation; in this case, the position of the maximum is shifted toward later time intervals with increasing LET of radiation.

Proton-beam irradiation (1, 2, and 4 Gy, 150 MeV) of hybrid male mice F1 (CBA × C57BL/6J) has changed their adaptive behavior in a different ways. The irradiated mice performed significantly less successfully than control ones in the puzzle-box test at those stages when the underpass to the safe box compartment was masked by wood shavings, and they had to dig to get to it. At the same time, they were significantly more successful at the stages when the underpass was masked by a light plug, which should be removed as it blocked the entrance. A reduction in neurogenesis in two proliferative forebrain zones had been demonstrated in irradiated mice.

Fundamental research on the harmful effects of ionizing radiation on living cells continues to be of great interest. Recently, priority has been given to the study of high-charge and high-energy (HZE) ions that comprise a substantial part of the galactic cosmic ray (GCR) spectra that would be encountered during long-term space flights. Moreover, predictions of the delayed genetic effects of high linear energy transfer (LET) exposure is becoming more important as heavy ion therapy use is increasing. This work focuses mainly on the basic research on the delayed effects of HZE ions on V79 Chinese hamster cells, with emphasis on the induction of HPRT mutations after prolonged expression times (ET). The research was conducted under various irradiation conditions with accelerated ions 18O (E = 35.2 MeV/n), 20Ne (E = 47.7 MeV/n and 51.8 MeV/n), and 11B (E = 32.4 MeV/n), with LET in the range from 49 to 149 keV/μm and with 60Co γ-rays. The HPRT mutant fractions (MF) were detected in irradiated cells in regular intervals during every cell culture recultivation (every 3 days) up to approximately 40 days (70–80 generations) after irradiation. The MF maximum was reached at different ET depending on ionizing radiation characteristics. The position of the maximum was shifting towards longer ET with increasing LET. We speculate that the delayed mutations are created de novo and that they are the manifestation of genomic instability. Although the exact mechanisms involved in genomic instability initiation are yet to be identified, we hypothesize that differences in induction of delayed mutations by radiations with various LET values are related to variations in energy deposition along the particle track. A dose dependence of mutation yield is discussed as well.

The impact of γ radiation of 137 Сs (doses of 1 and 3 Gy), low-intensity laser radiation (λ = 670 nm, 5.3 or 10.6 J/cm 2 ) as well as the influence of consecutive laser and γ radiation on peripheral blood and blood cells (erythrocytes, leukocytes, lymphocytes, granulocytes) were studied by analyzing the number of blood cells, blood absorption spectra, and activity of antioxidant defense enzymes. Two series of experiments were performed on four groups of rats. The rats of the control group (group 1) were not exposed to γ or laser radiation. In the experimental groups, single irradiation of the whole body of rats with γ radiation (group 2), three- or four-day over-vein irradiation of blood in the tail vein by low-intensity laser radiation (group 3), and successive three- or four-day irradiation of blood by laser and then a single irradiation of the whole body with γ radiation (group 4) were performed. It was shown that changes of the blood cell content in the experimental groups are accompanied by changes in the spectral characteristics of the blood and the activity of antioxidant defense enzymes. The radioprotective effect of low-intensity laser radiation is manifested as an increase in the average number of leukocytes and lymphocytes in the group as compared with the postradiation, as well as an increase in the activity of antioxidant protection enzymes. The possibility of using low-intensity optical radiation for correction of hematological disorders caused by ionizing radiation is discussed.

In this paper, two types of fullerene C60 solutions are compared with respect to their structural features and toxic properties. The results are discussed in terms of their potential in medical and biological applications. The fullerene cluster state at the nanoscale in these solutions is analyzed by small-angle neutron scattering. Experiments on the cytotoxicity of these systems on Chinese-hamster V-79 cells showed no toxic effects of the solutions.