State of the mineral component of rat bone tissue during hypokinesia and the recovery period

Experiments were conducted on young growing rats. Hypokinesia lasting from 20 to 200 days caused retarded gain in weight and volume of the femur and delayed development of the cortical layer of the diaphysis. In contrast, the density of the cortical layer of the femoral diaphysis increased due to elevation of the mineral saturation of the bone tissue microstructures. Incorporation of Ca into the bone tissue in hypokinesia had a tendency to reduce. Partial normalization of the bone tissue mineral component occurred during a 20 day recovery period following hypokinesia

Effect of six-month hypokinesia in dogs on mineral component, reconstruction and mechanical properties of bone tissue

Ca45 incorporation into the bones of the limbs, particularly in the area of the muscle attachment increased in dogs as a result of 6 month hypokinesia. There were no phenomena of osteoporosis in the cortical layer of the diaphyses; however, changes in the form of osteons, an increase in the number of anastomoses between the channels and the thinning of the subperiosteal layer pointed to disturbances of the bone tissue reconstruction. Mineral saturation of the bone microstructures of the experimental dogs had a tendency to rise. No changes in the mechanical properties of the long bones occurred as a result of hypokinesia in dogs

Comparative analysis of the content of metals and ecotoxicants in the hair of 7-year-old girls, living in different environmental conditions

The investigation and the comparative analysis of the content of metals (ecotoxicants) in the hair of 7-year-old girls, attending the first grade of a comprehensive school, living in different environmental conditions, were carried out. In a modern industrial city with a developed petrochemical infrastructure, there are chemical substances in the air, which often exceed the maximum permissible concentration, and the prolonged exposure of toxic substances causes a change in the functional state of the developing organism. In the conditions of technogenic pollution of the environment, it is especially important to study the impact of metals and ecotoxicants, having a toxic effect on the human body. The scale of growth of modern production is so large, that the amount of substances, emitted per unit of time, is much greater than the amount, which can be neutralized by the environment. Based on the numerous observations, it can be stated, that children are particularly sensitive to the impact of unfavorable environmental factors. Growing organism is characterized by the lowest threshold of perception to the influence of pollutants, high reactivity to external influences, and the degree of its adaptive capacity depends on the age, gender and a number of other individual characteristics. Such experimental direction has an applied significance and is of great scientific and practical interest, since it reflects the general state of the organism and the morphofunctional status of children of the age under study, living in different environmental conditions. On this basis, the study of the content of metals and ecotoxicants in the hair of seven-year-old girls, attending the first grade of a comprehensive school, living in different environmental conditions, was carried out. The following methods were used in the study: biochemical, statistical and the method of directed selection of the contingent. In the process of the study it has been found, that environmental pollution is one of the causative factors of reducing the adaptive capacity of the body, and the peculiarities of hair chemical composition, in regards to the studied substances, are determined by the ecological conditions of living

Biomedical aspects of student`s health activity at the State college of Olympic reserve and physical education

This research highlights the importance of health-improving exercises for students during their training sessions in the gym. The main idea is to show how exercising choice depends on body type. According to our research it was discovered that body type plays a big role in choosing definite program for students and helps them to reach the best resultsПредставлено исследование организации оздоровительных занятий студентов ГУОР в условиях тренажерного зала в зависимости от типов телосложения. Показано, что знание своего типа телосложения оказывает значимое влияние на выбор соответствующей тренировочной программ

Silicate weathering in anoxic marine sediments

Two sediment cores retrieved at the northern slope of Sakhalin Island, Sea of Okhotsk, were analyzed for biogenic opal, organic carbon, carbonate, sulfur, major element concentrations, mineral contents, and dissolved substances including nutrients, sulfate, methane, major cations, humic substances, and total alkalinity. Down-core trends in mineral abundance suggest that plagioclase feldspars and other reactive silicate phases (olivine, pyroxene, volcanic ash) are transformed into smectite in the methanogenic sediment sections. The element ratios Na/Al, Mg/Al, and Ca/Al in the solid phase decrease with sediment depth indicating a loss of mobile cations with depth and producing a significant down-core increase in the chemical index of alteration. Pore waters separated from the sediment cores are highly enriched in dissolved magnesium, total alkalinity, humic substances, and boron. The high contents of dissolved organic carbon in the deeper methanogenic sediment sections (50–150 mg dm−3) may promote the dissolution of silicate phases through complexation of Al3+ and other structure-building cations. A non-steady state transport-reaction model was developed and applied to evaluate the down-core trends observed in the solid and dissolved phases. Dissolved Mg and total alkalinity were used to track the in-situ rates of marine silicate weathering since thermodynamic equilibrium calculations showed that these tracers are not affected by ion exchange processes with sediment surfaces. The modeling showed that silicate weathering is limited to the deeper methanogenic sediment section whereas reverse weathering was the dominant process in the overlying surface sediments. Depth-integrated rates of marine silicate weathering in methanogenic sediments derived from the model (81.4–99.2 mmol CO2 m−2 year−1) are lower than the marine weathering rates calculated from the solid phase data (198–245 mmol CO2 m−2 year−1) suggesting a decrease in marine weathering over time. The production of CO2 through reverse weathering in surface sediments (4.22–15.0 mmol CO2 m−2 year−1) is about one order of magnitude smaller than the weathering-induced CO2 consumption in the underlying sediments. The evaluation of pore water data from other continental margin sites shows that silicate weathering is a common process in methanogenic sediments. The global rate of CO2 consumption through marine silicate weathering estimated here as 5–20 Tmol CO2 year−1 is as high as the global rate of continental silicate weathering

Triphenilphosphonium Analogs of Chloramphenicol as Dual-Acting Antimicrobial and Antiproliferating Agents

Activitat antibiòtica; Ribosoma bacterià; Simulacions de dinàmica molecularActividad antibiótica; Ribosoma bacteriano; Simulaciones de dinámica molecularAntibiotic activity; Bacterial ribosome; Molecular dynamics simulationsIn the current work, in continuation of our recent research, we synthesized and studied new chimeric compounds, including the ribosome-targeting antibiotic chloramphenicol (CHL) and the membrane-penetrating cation triphenylphosphonium (TPP), which are linked by alkyl groups of different lengths. Using various biochemical assays, we showed that these CAM-Cn-TPP compounds bind to the bacterial ribosome, inhibit protein synthesis in vitro and in vivo in a way similar to that of the parent CHL, and significantly reduce membrane potential. Similar to CAM-C4-TPP, the mode of action of CAM-C10-TPP and CAM-C14-TPP in bacterial ribosomes differs from that of CHL. By simulating the dynamics of CAM-Cn-TPP complexes with bacterial ribosomes, we proposed a possible explanation for the specificity of the action of these analogs in the translation process. CAM-C10-TPP and CAM-C14-TPP more strongly inhibit the growth of the Gram-positive bacteria, as compared to CHL, and suppress some CHL-resistant bacterial strains. Thus, we have shown that TPP derivatives of CHL are dual-acting compounds targeting both the ribosomes and cellular membranes of bacteria. The TPP fragment of CAM-Cn-TPP compounds has an inhibitory effect on bacteria. Moreover, since the mitochondria of eukaryotic cells possess qualities similar to those of their prokaryotic ancestors, we demonstrate the possibility of targeting chemoresistant cancer cells with these compounds.This research was funded by RFBR [grants 20-04-00873 to N.V.S. (synthesis of analogs, binding assays, in vitro translation), 20-015-00537 to P.A.N. (potential measurement, screening of TolC-containing transporters), and 20-54-76002 to I.A.O. (toeprinting and in vitro translation)], President grant MD 2626.2021.1.4 to I.A.O. (bacteria inhibition assays), grants from the Instituto de Salud Carlos III: PI17/02087 to A.L. (cancer cell proliferation assays) by the Ministry of Science and Higher Education of the Russian Federation [grant FENU-2020-0019 to G.I.M. (molecular dynamics simulations)] and by the Government of the Russian Federation [No. AAAA-A17-117120570004-6 to A.A.B.]

Spectral and Thermodynamic Characteristics of Complexes of Seleno- and Thioacetals with Iodine

Seleno- and thioacetal complexes of iodine were studied spectrophotometrically. The spectral and thermodynamic parameters of the complexes are compared with the special features of the electronic and steric structure of the donor molecules and with the characteristics of tetracyanoethylene complexes of the same compounds

Preferences of Hungarian consumers for quality, access and price attributes of health care services — result of a discrete choice experiment

In 2010, a household survey was carried out in Hungary among 1037 respondents to study consumer preferences and willingness to pay for health care services. In this paper, we use the data from the discrete choice experiments included in the survey, to elicit the preferences of health care consumers about the choice of health care providers. Regression analysis is used to estimate the effect of the improvement of service attributes (quality, access, and price) on patients’ choice, as well as the differences among the socio-demographic groups. We also estimate the marginal willingness to pay for the improvement in attribute levels by calculating marginal rates of substitution. The results show that respondents from a village or the capital, with low education and bad health status are more driven by the changes in the price attribute when choosing between health care providers. Respondents value the good skills and reputation of the physician and the attitude of the personnel most, followed by modern equipment and maintenance of the office/hospital. Access attributes (travelling and waiting time) are less important. The method of discrete choice experiment is useful to reveal patients’ preferences, and might support the development of an evidence-based and sustainable health policy on patient payments

Structure and evolution of dune massifs in the Vilyui River Basin over the Late Quaternary Period (by the example of the Makhatta and Kysyl-Syr Tukulans)

© 2017, Pleiades Publishing, Ltd. The data of the comprehensive study of deposits of dune sand massifs—the Makhatta and Kysyl-Syr Tukulans—in the Vilyui River Basin (Central Yakutia) are given. We have revealed the structure and preliminarily reconstructed the evolution of tukulans in the Vilyui River basin and the environmental conditions of the surrounding area in the Late Pleistocene–Holocene period (the chronological period of the formation of tukulans) on the basis of lithological and palynological data and 17 radiocarbon datings. It has been revealed that the tukulans should be assigned to eolian deposits formed on sediments of complicated facial structure. We have distinguished four stages in the vegetation evolution within the last 40000-year period and three chronostratigraphical phases in the development of dune massifs