Course Of Intake Research Articles

Metabolic estimation of efficiency of vitamin and mineral complexes in qualified athletes

In professional athletes who adapt to intense physical training and psycho-emotional stress, the formation of oxidative stress is shown. This fact determines the expediency of targeted correction of disorders of the balance of pro- and antioxidant systems in blood and tissues caused by intense physical training. The aim of the work was to study the effect of vitamin-mineral complex on the parameters of oxidative blood metabolism in professional athletes. Material and methods. The prospective study included 74 professional athletes representing cyclic sports and randomized into 2 groups: the main group (n=42), who personalized received one of two vitamin-mineral complexes (with different concentrations of antioxidants), and a control group (n=32), who received a placebo. The duration of the course of daily intake of vitamin-mineral complex, an additional source of vitamins C, E, A, D, group B, minerals and trace elements, a source of β-carotene (1.5 mg), lutein (4.5 mg) and L-carnitine, was 30 days. The parameters of oxidative metabolism of blood (the level of 8-isoprostan, oxidized low-density lipoproteins, superoxide dismutase activity, the concentration of carotenes, tocopherols, lycopene, lutein and zeaxanthin) were studied in the athletes of both groups before and after the course of intake, and in the main group these results were used to individualize the metabolic correction. Results. After completing the course of metabolic support, an increase in the concentration of lutein and zeaxanthin (1.26 fold), α- and β-carotene (1.21 and 1.17 fold, respectively), α- and γ-tocopherol (1.46 and 1.62 fold), and the coefficient vitamin E/cholesterol (1.18 fold) have been demonstrated in athletes. In addition, activation of superoxide dismutase (1.24 fold) and a decrease in the level of 8-isoprostane (1.49 fold) have been recorded. No such changes have been observed in the athletes included in the control group. Conclusion. It was found that the course of metabolic support, including the use of individually prescribed vitamin-mineral complex, allowed to optimize the state of oxidative metabolism of athletes blood plasma.

THE MAYAK WORKER DOSIMETRY SYTEM (MWDS-2013): DETERMINATION OF THE INDIVIDUAL SCENARIO OF INHALED PLUTONIUM INTAKE IN THE MAYAK WORKERS.

In order to estimate doses of workers exposed to plutonium, it is necessary to make assumptions about both the route and the time course of intake. The objective of this study was to determine a time course for the inhalation rate for plutonium (intake regime) useful for biokinetic modeling. Records from workplace air sampling, personnel biophysical examinations and autopsy data from former Mayak Production Association (MPA) workers were used. Plutonium accumulation strongly correlated with the volumetric activity of plutonium in workplace air. Using data from activity in air at MPA workplaces over time, a three-step function of intake was adopted. The adequacy of this three-step function was tested by comparing predicted doses using more complicated intake regimes. Uncertainties on the three-step function were also characterized based on air sampling data. The three-step function was assumed to be common to all workers, but an individual intake regime for each worker was calculated by convoluting it with the worker's actual employment history.

The development of opiate addiction in the rat

Opiate intake was studied in rats, which were given free choice between water and etonitazene (ETZ) solutions (2, 4, and 8 mg/l) for 30 weeks. After an abstinence of 19 weeks, the opiate was reoffered. The long-term course of intake could be subdivided in three phases: a period of controlled intake (25 weeks), a period of increasing consumption (week 25–30), and the stage of drug addiction (retest). During controlled intake, environmental and individual variables reversibly influenced ETZ intake (high intake in socially deprived and in subordinate rats, low intake in group-housed and in dominant rats). After 25 weeks of situation-specific intake, the rats spontaneously increased ETZ consumption. In the retest after long-term ETZ-abstinence, their intake was strongly increased compared to both their own intake before and to that of drug-naive controls. ETZ intake could no longer be influenced by environmental, gustatory, or individual factors (“loss of control”) indicating opiate addiction. In contrast, rats that have formerly had forced administration by means of a 2 mg/l ETZ solution did not become addicted. Signs of opiate withdrawal, however, occured in both series of forced and voluntary intake. Principles of the temporal development of opiate addiction are compared with those described previously for ethanol addiction.

Free choice ethanol intake of laboratory rats under different social conditions

To study the effects of different kinds of social deprivation on voluntary ethanol (ETOH) intake male Wistar rats were housed by (a) individual caging, (b) "contact" caging (partial social deprivation), and (c) group caging (four individuals per cage). In the latter condition the individuals were separated once a week from each other for 24 h. The rats simultaneously received water 5%, 10% and 20% ETOH for a period of 14 weeks. Additional control animals received water. Isolated individuals drank significantly more alcohol than group-housed or contact-caged rats. After a few days they preferred the 20% solution. Circadian measures revealed a discontinuous intake of high doses (greater than 0.5 g/kg/h) during short time periods. Contact-caged rats consumed much less ETOH, but both the preference for 20% ETOH and the circadian course of intake were similar to those occurring after isolation. ETOH intake of group-housed individuals was low. These individuals preferred the 5% solution and continuously consumed small ETOH doses. During the period of short-term isolation they drank even more ETOH than long-term isolated individuals. In contrast to the latter, the enhancement of intake decreased after some weeks. It is suggested that the differences between the housing groups not only reflect different degrees of isolation stress, but may also be explained by a contribution of different reinforcing or aversive psychotropic effects of ETOH. Reduction of isolation stress is probably most important in the situation of short term separation, whereas dose-dependent reinforcement via social stimulation or sedation may affect the drug taking behavior under the other social conditions.