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Free-space terahertz signal is encoded onto an optical signal probing the absorption of CdSe/CdS core/shell quantum dots, utilizing quantum-confined Stark effect. The demonstrated ultrafast electro-absorption modulation could support Tbit/s data rates with extinction ratio exceeding 6 dB. © 2024 The Authors.

To preserve reproductive cells of rare and endangered species of sturgeon fish using low-temperature cryopreservation methods, acoustic-mechanical impact with the use of piezoactuators was used. As a result of the research, the optimum parameters of signal frequency and time of impact on sturgeon cells were established, at which a high survival rate of sperm after defrosting was observed.Using mathematical modelling, the mechanism of acoustic-mechanical influence was studied, which consists in the wave and mechanical action created by the piezoactuator, which leads to acceleration of the process of diffusion of the cryoprotector inside the cells.For the first time a new methodological approach to low-temperature preservation of fish reproductive cells with the use of acoustic-mechanical impact has been proposed, which makes it possible to preserve genetic material with high survival rate and quality indicators.

This study was conducted in order to investigate of the points of formation of ice particles during cooling of fish sperm. The object of the study was spermatozoa of the Russian sturgeon (Acipenser gueldenstaedtii Brandt, 1833), hybrid Acipenser ruthenus × Huso huso, the spiny-tailed sturgeon Acipenser nudiventris Lovetsky, 1828, and the inconnu Stenodus leucichthys Güldenstädt, 1772. The growth of ice microparticles is formed at the perturbation temperature of the corresponding aqueous suspension, with the concentration of dissolved substances increasing in the non-freezing phase. The process of ice formation and the increase concentration of the remaining liquid continues as it cools to form amorphous (glassy) ice. It is interesting to bring the mass of ice with a further decrease in temperature to (-196) ° C. Cooling causes compression of the formed ice crystals.

The sperm of Russian sturgeon (Acipenser gueldenstaedtii Brandt et Ratzeburg, 1833) was the research object. Acoustic-mechanical influence on sturgeon semen improves fish-biological and reproductive indices of the seminal fluid. The most optimal indices for reproductive cells of male Russian sturgeon are 500 Hz, 90 V with the exposure duration of 1 minute. It has been shown that when a piezo-actuator with a frequency of 500 Hz and an amplitude of 90 V is applied to the sperm mixture with the cryoprotectant, ice crystals are formed later, which may influence the survival of cells after defrosting.

Advances in nanotechnology in various fields of human activity contribute to increase of their production, improved properties and wider implementation of nanomaterials. However, increasing use may enhance their release into the environment and can lead to affecting human health. The toxicity of colloidal solutions of metal nanoparticles (Cu, Mn) and their oxides, obtained in the absence and presence of a stabilizer, was examined and compared with the use of the standard test system of Allium cepa L.. The phytotoxicity of the experimental solutions was evaluated according to the growth response of the onion roots; the cyto- and genotoxicity were estimated due to the proliferative activity of the root meristem cells. It was established that solutions of stabilized metal nanoparticles were at given concentration toxic to Allium cepa L. according to the integral index of roots growth, however, were not cytotoxic. Difference in the phytotoxicity of stabilized and non-stabilized metal nanoparticles and their oxides depended on their phase composition and affected root growth.

To improve the quality of the frozen material during cryopreservation, scientists apply various effects on cells: mechanical, chemical or physical. In this work we use acoustic-mechanical effects on cells before cryopreservation. As a result of the studies, the optimal parameters of the impact of the piezoactuator were selected to improve the quality of defrosted reproductive cells of male sturgeons. The object of research was the sperm of the Russian sturgeon. The progressive motility time of native spermatozoa posure time (0.5 min; 1 min, 1.5 min) and frequency (300 Hz, 500 Hz, 550 Hz) were used. Analysis of the motility of thawed sperm showed that the best result in terms of the percentage of sperm motility was obtained when using a frequency of 500 Hz for 1 minute (27%). At the same time, the best indicator of sperm motility time was given by using a frequency of 300 Hz for 1 minute (390 s).

Ukraine’s further economic growth should be directed by Government Sustainable Development Strategy for harmonization of economy, environmental and social protection. One of the important modern problems is pollution by waste. The feasibility of introducing an eco-project for the municipal solid waste recycling is substantiated at the present research. The complex mathematical model of profit forecast is developed, which shows the tariffs influence on profitability of eco-project on construction of the plant for municipal solid waste recycling in Poltava region of Ukraine. The authors determine and analyse the dependences of the expected eco-project revenue from the change in tariffs for waste management services for each of the consumer categories. Two scenarios of economic development (inertial and innovative) are compared and resulted that the both scenarios have environmental and economic effect, so they are investment attractive. Emphasis is placed on the shortcomings and gaps of the existing tariff policy. The paper demonstrates lack of incentives for the development of business recycling under the existing tariff policy, so to establish a single tariff is proposed uniting the services cost for the removal, sorting, processing and disposal of the waste and also without dividing by consumer categories.

In gliomas, expression of certain marker genes is strongly associated with survival and tumor type and often exceeds histological assessments. Using a human interactome model, we algorithmically reconstructed 7494 new-type molecular pathways that are centered each on an individual protein. Each single-gene expression and gene-centric pathway activation was tested as a survival and tumor grade biomarker in gliomas and their diagnostic subgroups (IDH mutant or wild type, IDH mutant with 1p/19q co-deletion, MGMT promoter methylated or unmethylated), including the three major molecular subtypes of glioblastoma (proneural, mesenchymal, classical). We used three datasets from The Cancer Genome Atlas and the Chinese Glioma Genome Atlas, which in total include 527 glioblastoma and 1097 low grade glioma profiles. We identified 2724 such gene and 2418 pathway survival biomarkers out of total 17,717 genes and 7494 pathways analyzed. We then assessed tumor grade and molecular subtype biomarkers and with the threshold of AUC > 0.7 identified 1322/982 gene biomarkers and 472/537 pathway biomarkers. This suggests roughly two times greater efficacy of the reconstructed pathway approach compared to gene biomarkers. Thus, we conclude that activation levels of algorithmically reconstructed gene-centric pathways are a potent class of new-generation diagnostic and prognostic biomarkers for gliomas.

We have examined cytogenetic status of the rural population living on dioxin-contaminated territories (DCT, TCDD in soil 2.6 ng/kg) compared to the villagers of the control area (TCDD in soil 0.18 ng kg(-1)). The examination took place almost 40 years after the war. The consequences of some confounding factors (years of residence in the region, farming, and aging) has been examined. Karyological analysis of buccal and nasal epitheliocytes among healthy adult males living on DCT and control area (26 and 35 persons) was conducted. A wide range of cytogenetic (micronuclei, nuclear protrusions), proliferative (binucleated cells and cells with doubled nucleus) and endpoints of cell death (cells with perinuclear vacuoles, with damaged nucleus membrane, condensed chromatin, pyknosis, karyorrhexis, karyolysis) had been analyzed. The frequent amount of cells with nuclear protrusions in both epithelia was slightly decreased in the DСT group. Biomarkers of early and late stages of nuclear destruction in buccal epithelium (cells with damaged nuclear membrane, karyolysis) were elevated significantly in DCT. Higher level of the same parameters was also identified in nasal epithelium. The cytogenetic status of healthy adult males on DCT had got "normalization" by present moment in comparison with our early data. Nevertheless, in exposed group some alteration of the cytogenetic status was being registered (mostly biomarkers of apoptosis). Years of residence (and exposure to dioxins) affected the cytogenetic status of DCT inhabitants, whereas no influence of farming factors (pesticides, fertilizers, etc.) had been discovered. Some biomarkers of proliferation and cell death were affected by aging., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

For the first time the multiorgan karyological analysis of five organs of rats was applied for the study of the cytogenetic and cytotoxic action of the four types of non-contact electrochemically activated water in the 30-days in vivo experiment. The effects of investigated waters were not detected in bone marrow polychromatic erythrocytes. "Anolyte" (ORP = -362 mV) did not have a negative effect on rats. "Catholyte-5" (ORP = +22 mV) and "Catholyte-25" (ORP = -60 mV) induced cytogenetic abnormalities in the bladder and fore stomach. The same catholytes and "Catholyte-40" (ORP = -10 mV) changed the proliferation indices: increased the mitotic index in the fore stomach epithelium and reduced the frequency of binucleated cells in the fore stomach, bladder and lungs. The increase in the rate of cells with cytogenetic abnormalities on the background of the promotion of mitotic activity can be considered as a manifestation of the negative effect, typical for catolytes, but the effect of each out of them has its own features.

The influence of light water with the reduced content of heavy stable isotopes of oxygen and hydrogen (deuterium) on the cytogenetic status of irradiated animals was investigated. In mice, hybrids of the first generation (CBA x C57B1) F1, the increase in the output (two-fold at the dose of 2 Gy) of aberrant mitoses in the cells of bone marrow and the decrease in the duration of the mitotic index of the first cellular cycle occurred under the influence of the two week maintenance before the irradiation on light water with ppm 35 obtained by the method of rectification as compared with the irradiated animals that were kept on the distilled water. It has been discovered that 24 h after irradiation the number of leukocytes in the group which consumed light water is lower than that in the animals that were contained on the distilled water. Moreover, the cellularity of the bone marrow in the group which consumed light water was higher than that in the animals that were contained on distilled water. The prolonged application of light water before irradiation (for 14 days) led to an increase in the sensitivity of the chromosomal apparatus of mice to γ-irradiation against the background of an increase in the mitotic activity of cells.

Experiments showed that drinking water supplemented with a complex of 12 microelements and organic acids stimulates body mass gain and strengthening of radioresistance in mice. Obviously, availability of water with the mineral and organic complex before and after irradiation was the factor in survival of a part of mice exposed to the absolutely lethal dose (7.6 Gy from gamma-quanta 60Co) and reduction of chromosomal aberrations rate in bone marrow cells in consequence of nonlethal (1 Gy) irradiation.

Titanium dioxide is manufactured worldwide in large quantities for use in a wide range of applications including as food additives, in cosmetics and pigments for coloring ingested and externally applied drugs. Although TiO(2) is chemically inert it can cause negative health effects, such as lung cancer in rats. However, the mechanisms involved in TiO(2)-induced genotoxicity and carcinogenicity have not been clearly defined and are poorly studied in vivo. In the present research genotoxicity and carcinogenicity of titanium dioxide were studied in a mouse model. We treated CBAB6F1 mice by oral gavage with titanium dioxide particles (microsized, TDM, 160nm; nanosized, TDN, 33nm) in doses of 40, 200 and 1000mg/kg bw, daily for seven days. Genotoxic effects were analyzed in the cells of brain, liver and bone marrow by means of the Comet assay and in the cells of bone marrow, forestomach, colon and testis with a poly-organ karyological assay (analysis of micronuclei, nuclear protrusions, atypical nuclei, multinucleated cells, mitotic and/or apoptotic index). TDM induced DNA-damage and micronuclei in bone-marrow cells and TDN induced DNA-damage in the cells of bone marrow and liver. TDM and TDN increased the mitotic index in forestomach and colon epithelia, the frequency of spermatids with two and more nuclei, and apoptosis in forestomach (only TDN) and testis. This is one of the first poly-organ studies of TDM- and TDN-induced genotoxicity in vivo in mice. These effects are caused by a secondary genotoxic mechanism associated with inflammation and/or oxidative stress. Given the increasing use of TiO(2) nanoparticles, these findings indicate a potential health hazard associated with exposure to TiO(2) particles., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The paper gives an assessment of the association of structural-functional (histological and cytological), cytogenetic, and cytotoxic changes in the analysis of various exposures of the body during both experiments (oral acrylamide) and population examinations (impact of pulp-and-paper mill waste on the nasal and oral mucosae). The assessment of the association of the study parameters is shown to serve to more completely objectify the pattern of actuating factors.

To evaluate the cytogenetic and cytotoxic effects of a set of pollutions in the town of Koryazhma, the investigators made a complete karyological analysis (cytogenetic, apoptotic, and indirect proliferation parameters) of buccal and nasal epithelial exfoliative cells in two groups of old school age children living at various distances from a pulp-and-paper mill (PPM). The residential area that is adjacent to the PPM can be considered to be poor in the influence of genotoxic factors since there were 1.6- and 1.65-fold increases in cytogenetic disorders and cells with an atypically shaped nucleus, respectively, with a 1.57-fold reduction in the level of cell apoptosis. Karyological changes were revealed in the nasal mucosa, rather than in the buccal mucosa, which permitted one to recommend for the evaluation of the influence of environmental factors, the impact of ambient air pollution in particular, and to conduct cytogenetic studies on the cells of not only the buccal epithelium (that has been better studied), but also those of the nasal epithelium.

Long-term studies of 2 (cytohistology and genetic monitoring) laboratories of the Research Institute of Human Ecology and Environmental Hygiene, Russian Academy of Medical Sciences, to investigate the influence of environmental factors in the experiments made it possible to develop a noninvasive procedure for evaluating their cytological and cytogenetic impacts on man. A concurrent study of morphofunctional (histological, cytological) and cytogenetic parameters in both experimental and field trials can substantially extend and refine the interpretation of responses to environmental factors, which generates a need for using these parameters in hygienic and epidemiological studies.

The mutagenic effect of antituberculous drug dioxazid was studied on rats receiving this preparation in a dose of 25 mg/kg (in conversion to dioxidine) via inhalation route for 3 months. The percentage of cells with micronuclei and the content of polychromatophilic erythrocytes among all bone marrow erythrocytes and percentage of cells with micronuclei, protrusions, and binucleated cells in the lungs and urinary bladder were evaluated. Dioxazid caused no changes in organs, except the increase in the percentage of binucleated cells in bladder epithelium, which attests to minor cytotoxic effect of the drug for this organ.

Antibacterial preparation dioxidine administered four times in doses of 10, 100, and 300 mg/kg increased the incidence of micronucleated cells in the bone marrow, lungs, and large intestine of mice. Bone marrow cells were most sensitive, while cells of the lungs and large intestine exhibited lower sensitivity to the cytogenetic effect of dioxidine.

Some physicochemical properties of the microbial exopolysaccharide (EPS) ethapolan synthesized by Acinetobacter sp. 12S depended on whether the producer was grown on a mixture of ethanol and glucose or on single substrates. Irrespective of the carbon source in the nutrient medium, the contents of carbohydrates, pyruvic acid, uronic acids, and mineral components in the EPS remained unchanged. The EPS were also identical in their monosaccharide composition: the molar ratio of glucose, mannose, galactose, and rhamnose was 3:2:1:1. EPS with a higher proportion of fatty acids was synthesized during growth on the mixture of ethanol and glucose. Average molecular weight and the proportion of high-molecular (over two million) fractions were greater in ethapolan produced on the substrate mixture. In the presence of 0.1 M KCl, after transformation into the H+ form, and in the Cu(2+)-glycine system, solutions of these EPS showed higher viscosity than solutions of EPS synthesized on single substrates. The reasons for the improved rheological properties of the EPS produced on the substrate mixture are discussed.

The possibility of intensifying the synthesis of microbial exopolysaccharides (EPS) by a strain of Acinetobacter sp. grown on a mixture of two substrates nonequivalent in terms of bioenergetics (ethanol + glucose) was shown. Based on theoretical calculations of the energy requirements for biomass and EPS synthesis from the energy-deficient substrate (glucose), the supplementary concentration of the energy-excessive substrate (ethanol) was determined that prevents the loss of glucose carbon that occurs when glucose is oxidized to CO2 to obtain energy for the processes of constructive metabolism. This made it possible to increase the efficiency of conversion of the substrate carbon to EPS. The introduction of ethanol into glucose-containing medium at a molar ratio of 3.1:1 allowed the amount of the EPS synthesized to be increased 1.8- to 1.9-fold; their yield relative to biomass increased 1.4- to 1.7-fold, and the yield of EPS relative to the substrate consumed increased 1.5- to 2-fold as compared to growth of the producer on single substrates. These results form the basis for the development of new technologies for obtaining secondary metabolites of practical value with the use of mixed growth substrates.

Enhanced synthesis of the exopolysaccharide (EPS) ethapolan by Acinetobacter sp. 12S was observed when the bacterium was grown on a mixture of two energetically nonequivalent substrates (ethanol and glucose) taken in a molar proportion of 3.1:1. The efficiency of carbon transformation into EPSs was maximum when sodium ions were absent in the medium, the concentration of nitrogen source was reduced to 0.3-0.45 g/l, and the inoculum was grown on ethanol. Such conditions provided an increase in the maximum specific growth rate and its attainment in earlier cultivation terms. Molasses as a substitution for glucose was inefficient. The activities of the key enzymes of C2-metabolism in Acinetobacter sp. 12S cells grown on the substrate mixture was 1.1 to 1.7 times lower than they were during growth on ethanol alone. The activity of isocitrate lyase in cells grown on the substrate mixture declined to an even greater extent (by 4 to 7 times), indicating that the role of the glyoxylate cycle in such cells is insignificant.

An Acinetobacter sp. strain grown on carbohydrate substrates (mono- and disaccharides, molasses, starch) was shown to synthesize exopolysaccharides (EPS). Glucose catabolism proved to proceed via the Embden-Meyerhof-Parnas and Entner-Doudoroff pathways. Pyruvate entered the tricarboxylic acid cycle due to pyruvate dehydrogenase activity. Pyruvate carboxylation by pyruvate carboxylase was the anaplerotic reaction providing for the synthesis of intermediates for the constructive metabolism of Acinetobacter sp. grown on C6-substrates. The C6-metabolism in Acinetobacter sp. was limited by coenzyme A. Irrespective of the carbohydrate growth substrate (glucose, ethanol), the activities of the key enzymes of both C2- and C6-metabolism was high, except for the isocitrate lyase activity in glucose-grown bacteria. Isocitrate lyase activity was induced by C2-compounds (ethanol or acetate). After their addition to glucose-containing medium, both substrates were utilized simultaneously, and an increase was observed in the EPS synthesis, as well as in the EPS yield relative to biomass. The mechanisms responsible for enhancing the EPS synthesis in Acinetobacter sp. grown on a mixture of C2- and C6-substrates are discussed.