Toxic effect of copper-zinc pyrite ore on erythropoiesis in chronic experiment

Natural ores contain a large number of harmful components for human health. Workers of mining and processing enterprises, who have long-term contact with these natural elements, are often diagnosed with anemia, that pathogenesis is not sufficiently studied. Aim of the study was to detail the mechanisms of rats’ erythron disorders in the long-termintoxication by natural complex of heavy metal compounds of copper-zinc pyrite ore.Material and methods. The work was performed on 60 white non-linear male rats aged 3-4 months weighing 220,52 ± 15,51 g. The experimental group of animals (n = 40) were injected orally with water suspension of copper-zinc powder in a bread crumb an hour before standard feeding during 75-120 days. The blood and bone marrow of experimental groups of rats were carried out on the 75-th, 90-th, 105-th and 120-th days of the experiment. The blood and bone marrow of rats’ control groups were studied on the 75-th and 105-th day. The central part of erythron was assessed by the number and composition of the erythroblastic islets (EI) of bone marrow, the number of free macrophages, the coefficients of involvement of colonyforming units of red blood cells (CFU-E) and macrophages into erythropoiesis.Results. In the peripheral blood of experimental rats the number of red blood cells and the content of hemoglobin were reliably less than the control values on the 90-th and 120-th day, the number of reticulocytes was exceeded the control group on the 75-th, 105-th and 120-th day. In the bone marrow of experimental rats there were only a single EI1 and EI2 classes of maturity. Throughout the experiment, the content of free macrophages and EI with reticulocytes «crown» in the bone marrow of rats was elevated, and the concentration of iron and erythropoietin in the blood, on the contrary, was reduced. The intensity of CFU-E involvement in the erythropoiesis was less than the control level by 2 times on 105th and 120th days of the experiment.Conclusion. With long-term introduction of copper-zinc pyrite ore in the bone marrow of rats the process of formation of EI de novo is suppressed by destabilizing the contact of free bone macrophages with young red blood cells. There is reduces in the content of serum erythropoietin and bound iron, that combines with the change of erythropoiesis nature, leads to decreasing of the number of mature red blood cells and content of hemoglobin in the peripheral blood

Preparing Children for Social Activity in Preschool Educational Organizations - Pedagogical Need

This article discusses the need to prepare students of the direction of preschool education" for social and pedagogical activities, the essence and priority principles of this process, the content of the training of future educators of the direction "Preschool education" the orientation of the child to social life,  the role of training sessions in preparing future educators for social and pedagogical activities, as well as the possibility of preparing students for the socialization of children in organizations of preschool education outside the auditorium, is highlighted

The impact of increased physical exertion on the state of adrenal cortex and pubertal development in boys

© 2014, Pleiades Publishing, Inc. The study of the functional state of the adrenal cortex (AC) in young athletes aged 11 to 15 years, which was assessed by daily free (Cf) and bound (Cb) cortisol excretion levels, and the comparison of these levels with those of the boys from the control group made it possible to conclude that the increased physical exertion in the form of regular athletic training had a dominating effect on the age-related changes in the AC and pubertal development in the young athletes. It was found that the 12- to 14-year-old athletes had stably high Cf excretion levels, which were significantly decreased by the age of 15 years on the background of high Cb levels, as compared to the nonathletes, whose urinary cortisol levels were significantly lower (p < 0.05) and were progressively increased (p < 0.05) from 13 to 15 years of age. It was found that pubertal development (the development of secondary sex characteristics) was relatively delayed in the athletes, and pubertal changes in the glucocorticoid function of the AC reflected mainly its adaptive responses providing the increased resistance of the child’s body to increased physical exertion

Influence of the initial autonomic tone on the state of hemodynamics of primary schoolchildren

The functional state of the cardiovascular system and its reaction to local isometric exercise in seven- and eight-year-old children was studied with consideration for the initial tone of the autonomic nervous system. Using the methods of variational pulsometry and tetrapolar thoracic rheography, it was established that children with predominant sympathetic influences on the heart rate (67-56. 55% of the total number of those examined) had increased stroke and minute blood volumes against the background of relative tachycardia, compared with normo- and vagotonics. In sympathotonic boys, the leading component in the mechanism of urgent adaptation of the cardiovascular system to static exercise is spastic reactions of the vascular bed, which allow this contingent of schoolchildren to be identified as a group of children at high risk of autonomic dystonia with the hypertensive vascular syndrome. © 2012 Pleiades Publishing, Ltd

Improving the performance of the organization in the implementation of quality management system

When developing and implementing a quality management system, the competence of all employees, productivity and efficiency of the organization are improved, along with the improvement of product quality indicatorsПри разработке и внедрении системы менеджмента качества достигаются повышение компетентности всех сотрудников, производительности и эффективности организации, вместе с этим улучшаются показатели качества продукци

Criteria for improving the efficiency of metrological support of production

Повышение эффективности производства и качества выпускаемой продукции возможно только при организации современного метрологического обеспечения на этапах проектирования и разработки, производства и испытаний.Improving the efficiency of production and quality of products is possible only with the organization of modern metrological support at the stages of design and development, production and testing

Reaction of the adrenal cortex to graded exercise in children with different initial tonus of the autonomic nervous system

It was found that the response of the adrenal cortex to graded bicycle exercise in children depends on the initial autonomic tonus and is adequate to the background excretion level of hormone metabolites. Seven-year-old sympathotonic girls with increased excretion of 17-hydroxycorticosteroids at rest demonstrated the lowest increase in this parameter after exercise in comparison with more pronounced increment in vagotonics with relative low initial level of glucocorticoid metabolites. Enhanced excretion of glucocorticoid metabolites with a decrease in androgens observed in 9-year-old sympathotonic girls attests to predominance of catabolic processes over anabolic ones and low efficiency of switching from muscle exercise to recovery in children. © 2013 Springer Science+Business Media New York

Influence of the initial autonomic tone on the state of hemodynamics of primary schoolchildren

The functional state of the cardiovascular system and its reaction to local isometric exercise in seven- and eight-year-old children was studied with consideration for the initial tone of the autonomic nervous system. Using the methods of variational pulsometry and tetrapolar thoracic rheography, it was established that children with predominant sympathetic influences on the heart rate (67-56. 55% of the total number of those examined) had increased stroke and minute blood volumes against the background of relative tachycardia, compared with normo- and vagotonics. In sympathotonic boys, the leading component in the mechanism of urgent adaptation of the cardiovascular system to static exercise is spastic reactions of the vascular bed, which allow this contingent of schoolchildren to be identified as a group of children at high risk of autonomic dystonia with the hypertensive vascular syndrome. © 2012 Pleiades Publishing, Ltd

The impact of increased physical exertion on the state of adrenal cortex and pubertal development in boys

© 2014, Pleiades Publishing, Inc. The study of the functional state of the adrenal cortex (AC) in young athletes aged 11 to 15 years, which was assessed by daily free (Cf) and bound (Cb) cortisol excretion levels, and the comparison of these levels with those of the boys from the control group made it possible to conclude that the increased physical exertion in the form of regular athletic training had a dominating effect on the age-related changes in the AC and pubertal development in the young athletes. It was found that the 12- to 14-year-old athletes had stably high Cf excretion levels, which were significantly decreased by the age of 15 years on the background of high Cb levels, as compared to the nonathletes, whose urinary cortisol levels were significantly lower (p < 0.05) and were progressively increased (p < 0.05) from 13 to 15 years of age. It was found that pubertal development (the development of secondary sex characteristics) was relatively delayed in the athletes, and pubertal changes in the glucocorticoid function of the AC reflected mainly its adaptive responses providing the increased resistance of the child’s body to increased physical exertion

Influence of the initial autonomic tone on the state of hemodynamics of primary schoolchildren

The functional state of the cardiovascular system and its reaction to local isometric exercise in seven- and eight-year-old children was studied with consideration for the initial tone of the autonomic nervous system. Using the methods of variational pulsometry and tetrapolar thoracic rheography, it was established that children with predominant sympathetic influences on the heart rate (67-56. 55% of the total number of those examined) had increased stroke and minute blood volumes against the background of relative tachycardia, compared with normo- and vagotonics. In sympathotonic boys, the leading component in the mechanism of urgent adaptation of the cardiovascular system to static exercise is spastic reactions of the vascular bed, which allow this contingent of schoolchildren to be identified as a group of children at high risk of autonomic dystonia with the hypertensive vascular syndrome. © 2012 Pleiades Publishing, Ltd