Цель исследования-изучить влияние имплантации в большеберцовую кость гидроксилапатита и перорального введения препаратов кальция на прочностные характеристики плечевых костей крыс. Эксперимент поставлен на 210 самцах лабораторных крыс, имеющих исходную массу тела от 135 до 145 г: А-группа-контроль, в Б-группе перфорировали большеберцовые кости, в В-группе производили пластику дефекта материалом ОК-015. В Г-группе после перфорации и в Д-группе после имплантации применяли «Биомин МК» внутрижелудочно через зонд из расчета 90 мг/кг/сутки. Прочность плечевых костей исследовали при изгибе с трехточечной моделью нагружения. Перфорация большеберцовых костей приводила к падению прочности плечевых костей с максимальными отклонениями к 30-м суткам после операции. Имплантирование материала ОК-015 в ранние сроки после операции сопровождалось усугублением выявленных отклонений, с 30-х суток восстановление прочности происходит быстрее. При внутрижелудочном зондовом введении препарата «Биомин МК» после перфорации большеберцовых костей величина минимальной работы разрушения превышала показатели Б-группы с 15-х по 180-е сутки на 7,07%,

Aim. To study the morphological features of lymph nodes in people aged 65-69 years and to analyze the results with data from other researchers. Materials and methods. The study was carried out on 30 lymph nodes obtained during autopsy of people aged 65-69 years. Lymph nodes were subjected to standard histological protocol; slides were stained with hematoxylin and eosin. An immunohistochemical study was performed to determine the expression of the markers Ki-67, p53, bcl-2 and Cyclin B1. Results. The thickening of the capsule and connective tissue trabecules were determined on the sections of the lymph nodes, the cleavage of trabecules by adipocytes. The zonal structure of the lymph node is smoothed. Lymphatic nodules in the cortex have unclear contours, they do not have germinal centers. The boundaries of the internodular zone and paracortex are not determined. The marginal sinus is unevenly expanded. In the medulla, medullary cords are replaced by white adipose tissue. The medullary sinuses are dilated, adipocytes are located in the lumen of some of them. Small arteries and arterioles with thickened walls and signs of hyalinosis occur. An immunohistochemical study of the proliferative activity of lymph node cells shows a significant decrease in the number of positively stained lymphocytes in both the cortex and medulla by the expression of the Ki-67 marker. In a study of the expression of Cyclin B1 and p53 receptors, the reaction is negative in both cases, while a reaction with antibodies to bcl-2 revealed weak cytoplasmic staining of lymphocytes of the cortex and medulla. Conclusion. Own and literature data shows that with age, unidirectional degenerative and dystrophic changes occur in the lymph nodes of humans, rats and mice. This results in increase in the proportion of connective and adipose tissue and a decrease in lymphoid tissue in the lymph nodes. These changes can be considered morphological signs of inhibition of lymphocytopoiesis, humoral and cellular immunity in the lymph nodes.

Currently, sodium benzoate is widely used in the food industry, cosmetology and medicine. The literature provides information about the effect of its introduction on the growth and shaping of bones, the parameters of the crystal lattice of the regenerate formed therein. However, information about the effect of this food additive on the phase composition of the bone regenerate being formed and the degree of this influence is practically absent, which was the purpose of the study. The experiment was conducted on 210 white male rats, divided into 6 groups: 1st - control animals, 2nd and 3rd - rats, daily receiving intragastrically 1 ml of sodium benzoate 500 and 1000 mg/kg/day, respectively for 60 days. The 4th group - rats being inflicted a defect in both tibial bones, and the 5th and 6th - rats being inflicted a defect after the end of the 60-day injection of sodium benzoate. The timing of the experiment after the introduction of sodium benzoate was 3, 10, 15, 24 and 45 days. The area of the forming regenerate of tibial bones was investigated by X-ray diffraction analysis: the percentage content in the mineral of the regenerate of whitlockite, hydroxylapatite and calcite was calculated by the method of internal control. The impact of the introduction of sodium benzoate and the application of the defect on the above indicators was evaluated by two-factor analysis of variance. The results of the study showed that 60-day administration of sodium benzoate leads to an increase in the amorphism of the biomineral of the forming regenerate of tibial bones, the severity and recovery rate of which depends on its administered dose. Thus, the group being inflicted the defect of the tibial bones after the completion of the 60-day administration of sodium benzoate at a dose of 500 mg/kg/day had greater calcite content on day 10 to 45 by 17.88%, 12.88% and 6.63%, and whitlockite - on day 3, 24 and 45 by 14.30%, 4.52% and 6.20%, and hydroxylapatite - less on day 15 to 45 by 3.11%, 3.31% and 2.14%, compared with the defect-inflicted group without the introduction of sodium benzoate. An increase in the administered dose of sodium benzoate up to 1000 mg/kg/day led to aggravation of the identified deviations: the whitlockite content on day 3, 24, and 45 was higher by 16.15%, 6.21% and 9.54%, and the hydroxylapatite content on day 15 to 45 was lower by 3.98%, 4.16% and 3.34%. The conducted two-factor analysis of variance showed that the introduction of sodium benzoate had a significant effect on the change in the content of calcite, whitlockite and hydroxylapatite in the regenerate, the strength and duration of which depends on its administered dose. The maximum power of influence was registered for the increased content of calcite and the decreased content of hydroxylapatite in the mineral of the regenerate on day 45 of the experiment, and for the increased content of whitlockite - on day 3. When a defect was inflicted, the power of influence was maximal for the increased content of calcite and decreased content of hydroxylapatite on day 10, and the increased content of whitlockite - on day 15. In this case, a reverse dose-dependent effect was observed in all periods of the experiment.

BACKGROUND: Osteoporosis and osteopenias are the most common metabolic diseases of skeleton leading to loss of bone mass, which in turn contributes to increase in the incidence of fractures occur against their background. To note, bone fractures often require not only correction of phosphorus-calcium metabolism, but also bone-plastic operations. AIM: To investigate the structure of the middiaphysis of the humeral bone after plastic surgery of the tibia defect with OK-015 material and substantiate the possibilities of correction of its damages by “Biomin MK”. MATERIALS AND METHODS: The experiment involved 210 male laboratory rats with initial body weight from 135 to 145 g: group A — control, in group B perforation of the tibia, in group C filling of the defect with OK-015 material. In the group D after perforation and in the group E after implantation, “Biomin MK” was used intragastrically through a tube at a dose of 90 mg/kg/day. RESULTS: Perforation of the tibia was accompanied by an increase in resorptive processes and inhibition of bone formation in the diaphysis of the humeral bone with maximum deviations by the 30th day after surgery. The implantation of the OK-015 material was accompanied by aggravation of the identified alterations within 15 days, but in the later period, the structure of the middiaphysis recovered faster. With intragastric administration of “Biomin MK” through a tube after the bone plasty, the structure of the middiaphysis of the humeral bones showed more evident changes by the 7th and 15th day, but by the 30th and 60th day after the implantation, the thickness of the layer of the external circumferential lamellae was greater than in group C by the 3.77% and 4.27%, and the thickness of the internal circumferential lamellae and the diameter of osteons by the 60th day — by 3.51%, 6.46% and 18.64%. CONCLUSIONS: The administration of “Biomin MK” during implantation of OK-015 material into the tibia is accompanied by the restoration of the structure of the middiaphysis of the humeral bones, mainly from the 30th to 60th days after the surgery.