FORMATION OF MALE FERTILITY IN ONTOGENESIS

The main human species mission is fertility, which is an important point of the concept of health in general and of reproductive health in particular. Endocrinologists, obstetrician-gynaecologists, urologists and paediatricians are focused in this field of medicine. A decline in male fertility of up to 30–35% results in infertility which becomes serious concerns growing for human population. Many of the problems that lead to impaired male fertility are rooted in childhood, or rather, in prenatal ontogenesis. The penetration of vascular-bed substances into the cavity of the seminiferous tubules depends on the maturity and functional status of the structures constituting the blood-testicular barrier (BTB). A breach of BTB results in damage to the sperm epithelium and, as a consequence, in different grades of impairment of spermatogenesis. Among the diseases that predispose men to infertility varicocele predominates (up to 30%). One of the reasons for infertility is the impaired integrity of BTB when the process of spermatogenesis changes, sometimes in combination with infection, trauma, and toxic effects. Given the unfavorable prognosis of the consequences of these diseases in children, their careful and timely diagnosis is important. Fertility estimation places special emphasis on the state of BTB, which can be determined by the content of claudine-11, antisperm antibodies, inhibin B, and other markers.

INFLUENCE OF INDUSTRIAL VIBRATION ON MINERAL METABOLISM, ORGANS OF THE ORAL CAVITY AND FETAL MYOCARDIUM

In the study, the morphometric analysis of bone trabeculae of the developing jaws, tooth buds, tongue muscles, masseter muscle, and myocardium of 20-day fetuses of Wistar rats, exposed to vibration from the 9th to the 18th day of prenatal ontogenesis, was performed. The concentration of Ca, Cd, Cu, Fe, Mg, P, Pb, Se, Zn was determined in the liver of pregnant females exposed to vibration. The morphometric study revealed an acceleration of the osteogenesis of jaws and dentinogenesis of tooth buds. In the myocardium and masseter muscle signs of interstitial edema and a decrease in the area of the vessels of the microvasculature are determined. In the liver, there is a decrease in the amount of Ca, Mg and Fe, which is accompanied by an increase in the content of Cd and Pb. The revealed shifts in mineral metabolism indicate gross impairment of chemicals' homeostasis in the mother-fetus system, which underlies the imperfect morphogenesis of the fetal dentition and will be the basis for the formation of pathology of orofacial organs and cardiovascular pathology in offspring.

MORPHOFUNCTIONAL FORMATION OF THE SKIN AS AN ORGAN IN THE PROCESS OF ONTOGENESIS

The development of new areas of medicine requires more accurate visualization of the structural components of the skin of laboratory rats, their spatial distribution and dynamics of changes in the postnatal period. The study was carried out on male Wistar rats skin at different periods of postnatal ontogenesis. There is a gradual accumulation and development of skin derivatives in the skin in the postnatal period, as well as structures laid down in prenatal ontogenesis. In connection with the addition of new functions performed by the skin, qualitative and quantitative morphological and functional changes occur in it.

INVESTIGATION OF EMBRYONIC HISTOGENESIS OF THE PAROTID GLAND

Lectinohistochemistry methods are very sensitive and allow to identify certain types and subpopulations of cells, to characterize non-cellular tissue structures in morphological studies, when they cannot be differentiated by using traditional methods of carbohydrate histochemistry. In many diseases, changes in the carbohydrate component of various glycoconjugates are observed, which contribute to the modification of morphofunctional characteristics of the cell and changes in its interaction with other cells and extracellular factors. Most studies are devoted to the study of the existing pathology of individual organs and systems (or their norms) in adults and animals. Data from the scientific literature on the histotopography of lectin receptors in the first months of human prenatal ontogenesis are few, and regarding the peculiarities of the expression of carbohydrate determinants of the rudiments of the human parotid gland in early prenatal ontogenesis - are absent. Glycopolymers compounds make up structural and functional basis of cells and tissues of a living organism. The necessity of anatomical-lectinohistochemical examination of the parotid gland in early prenatal period of ontogenesis is substantiated, as the evidences concerning its topography are fragmentary and unsystematized, and certain aspects of its ontogenesis are disputable. A natural redistribution of glycopolimers of the cytolemma and cytoplasm of the cells of the epithelial anlage of the parotid salivary gland and the mesenchyma adjacent to it in the course of investigating 50 human embryos and prefetuses aged up 21 days to 12 weeks at stages 9-23 and the beginning of the fetal period according to the classification of Carnegy’s institute has been revealed. Invagination of epithelial cells in the regions bucco-alveolar pockets into the underlying mesenchyme and their transformation into epithelial cords due to the accumulation of specific glycopolymers lectin WGA, SNA, HPA, RCA, LABA. The results of lectin-histochemical examination of the early prenatal ontogenesis of the parotid gland can form the basis for the work of laboratories dealing with screening of morphological material in order to assess the degree of maturation and prognosis of fetus viability and diagnostics of deviations from normal development.

Features of the structure of the muscles acting on the hip joint of the human fetus

Aim - to identify the features of the anatomical structure of the muscles acting on the hip joint in the fetal period of prenatal ontogenesis. Material and methods. The study was carried out on corpses of 200 fetuses aged from 12th to 38th weeks. Anatomical and morphometric research methods were used. Results. As a result of the study, it was established that the muscles of the pelvis and thigh of the fetus are different from the definitive ones: more heads are noted, a different direction of force action vector, functional indicators of the extensor and rotator muscles prevail. There are critical periods of organogenesis of functional muscle groups. Conclusions. The main trend of organogenesis of the muscles of the pelvis and thigh is the fusion of small muscle insertions into larger organs. A feature of the fetal muscles acting on the hip joint is the morpho - functional predominance of the insteps and adductor muscles that create the necessary conditions for the hip joint morphogenesis. The 20th-22th and 28th-30th weeks of intrauterine development are critical periods in human hip joint morphogenesis.

Results of 3-D reconstruction in dynamic analysis for determining the bone tissue density of the maxilla in human prenatal ontogenesis

The quality of the bone tissue of the jaw bones is of special significance since it is characterized by the pronounced age dynamics and depends both on the course of the mineralization of the skeleton as a whole, and on the specifics of the mineral content of the bone tissue of the particular jaws. The aim is to find out the peculiarities of bone density (MO Hu) in various anatomical areas of the germs of the human maxillary jaw in the dynamics of prenatal ontogenesis using computed tomography and standardized software i-CATVision. The study has been conducted using macroscopy, morphometry, computed tomography, and statistical analysis. The study of the germs of the maxilla in prenatal ontogenesis confirms the asynchrony of density, which is directly proportional to its mineralization, between the right and left sides, which is most pronounced in the alveolar, malar and palatal ridges. Mineral saturation of bone tissue, which reflects its density (MO Hu), is an interdependent coefficient of ratio to its growth rate (%). Alveolar ridges maintain a stable, non-correlated dynamic growth sequence in all experimental age groups, in the frontal area, with a rate of density increase (%) up to 30 weeks of prenatal ontogenesis. The highest density factor of the malar ridges accounts for the 11–16 weeks of the development of the fetus, in the percentage distribution of mineral saturation among the frontal, palatal and alveolar ridges, more than a third of the total value. This analysis forms the idea of the distribution of micro and macro elements that provide bone density, among the stable morphological structures of the maxilla and enriches knowledge with quantitative morphology and becomes a guide for further research and prenatal diagnostics of fetal development as well. We find it promising to carry out the research on mineral content and density of bone tissue of pathologically altered upper jaws of pre-fetuses, human fetuses, newborns and to study their development under conditions of external factors in ecologically unfavorable regions.