The aim of research was to study age-related changes of the human bulbourethral glands and features of their course in the benign prostatic hyperplasia.

Material and methods. The study included bulbourethral glands of 44 men aged 17–90. Patients in the second period of maturity with and without benign prostatic hyperplasia composed a separate group; their cases were analyzed separately. Geometric and optical parameters allowing evaluating age-related changes in the bulbourethral glands and distinguishing their characteristics in the benign  prostatic hyperplasia were measured using sections stained by the Mallory’s method and PAS-reaction.

Results. A decrease in height of glandulocytes, section area of the secretory units, and in total share of parenchyma was observed in the bulbourethral glands from adolescence to senile. The optical density of the glandulocyte cytoplasm was maximal in young men and significantly reduced in the first period of adulthood. In the second period of adulthood and elderly age, changes in this parameter were minor. In the senile period, the optical density of the glandulocyte cytoplasm was minimal in all compared age groups. Presence of PAS-positive material in glandular cells indicates the preservation of the ability to secretion in old age. In men of the second period of maturity with benign prostatic hyperplasia, all morphometric parameters of the bulbourethral gland parenchyma were higher than those in cases without nodal changes in the prostate. At the same time, the optical density of PAS-positive material in the glandulocyte cytoplasm exceeded twice similar values for men without this pathology.

Conclusion. Adolescence is a period of maximal activity of the bulbourethral glands. Involutive  parenchyma changes occurring from the first period of adulthood up to and including the elderly age were compensated by secretory cell activity sufficient to provide the necessary level of the bulbourethral  gland functioning. In old age, the bulbourethral glands retained the ability to secrete. In men of the second period of maturity with benign prostatic hyperplasia, functional activity increased compared to individuals without this pathology.

The aim of research was to study radiation-induced changes in the protein content in the brain neurons after exposure to small doses of ionizing radiation.

Material and methods. The study was performed in compliance with the rules of bioethics. The study included 300 male rats, aged 4 months at the beginning of the experiment, that were exposed to radiation in total doses of 0.1; 0.2; 0.5 and 1 Gy given as a single dose or fractionated (equal portions for 5 days with a dose rate of 0.5 and 6.6 Gy/h). Morphometric and tinctorial parameters of neurons and the dynamics of protein content in the brain neurons over the entire life span of animals were assessed using neuromorphological methods. The results obtained were statistically processed using software packages Statistica 6.1, which included parametric criteria and mathematical modeling.

Results. In animals of the control group and in animals exposed to radiation wave-like changes in the protein content in the brain neurons occurred during the whole life; in animals exposed to irradiation parameters of these changes gradually decreased by the end of the irradiation period. Regression analysis showed that irradiation in the studied doses had a nonlinear stochastic effect on the protein content in neurons, had no dose-time dependence and did not result in significant organic changes in the brain neurons. At the end of the experiment, with the death of both irradiated and control animals, the protein content in neurons was statistically significantly reduced in all groups, but to a greater extent in irradiated animals. Moreover, the greatest decrease in protein content was observed in the pear-shaped neurons of the cerebellar cortex, and the parietal cortex neurons were more resistant to the radiation factor in terms of protein content.

Conclusion. No significant radiation-induced changes in the content and topochemistry of histochemical reaction products were revealed when detecting protein in the structures of brain neurons. At the end of the experiment, the protein content in the neurons of the parietal cortex of the irradiated  animals practically correlated to that in animals of age control, and was statistically significantly reduced in other parts of the brain.

Local radiation injuries in the form of radiation ulcers resulting from the local exposure to ionizing radiation are characterized by a long wave-like course, poor prognosis for self-healing and require specialized high-tech treatment techniques. Damage to vessels of the microvasculature being a component of their pathomorphogenesis along with the damage to the epithelial and connective tissue cells, is one of the reasons for the morphological features of this type of damage. Gene induction of the vascular growth in the microvasculature can be a component of the local treatment of local radiation injuries.

The aim of the study was to assess the effect of a pro-angiogenic gene therapeutic preparation based on pl-vegf165 (Neovasculgen, Russia) on the healing process of simulated long-term nonhealing severe local radiation injuries (ulcers).

Material and methods. The study included white male rats (n=40), which were divided into 4 groups, 10 animals in each group: a control group, a group with a single administration of the preparation in 14 days after irradiation, a group with a double administration of the preparation in 14 and 27 days after exposure, and a group with a single late administration of the preparation in 35 days after exposure. Macroscopic planimetry was the main criterion for assessing the healing process. Routine histological and morphometric investigations were also performed.

Results. The study results demonstrated that statistically significant differences in the dynamics of local radiation injury healing on the criterion “the ulcer surface area” were registered between the control group and experimental groups in the long-term period – in more than 60 days.

Conclusion. The results obtained can be due to the development of new blood vessels of the  microvasculature resulting from the gene induction of angiogenesis.

Objective – to carry out comparative analysis of embryo survival and pregnancy rate after the vitrification of human embryos at different stages of the preimplantation development.

Material and methods. A total of 1311 embryos were analyzed. For vitrification of embryos, the Irvine Scientific media (USA) and the CryoTop open-type carriers (Japan) were used. The vitrification and the defrosting of embryos were carried out according to the manufacturer's recommendations. The statistical processing of the results was performed on a computer in the statistical computing environment R (R V. 3. 5. 3, RStudio V. 1. 1. 463), the primary data entry was performed using MS Excel spreadsheets. We used methods of descriptive statistics, tests for comparing proportions, including an accurate binomial test for small samples and a single-sample test of proportions with continuity correction for large samples.

Results. The range of the embryo survival is quite wide and ranges from 75% to 100%. When conducting a detailed analysis of the dependence of the pregnancy rate on the stage of cryopreserved blastocysts, we found a direct link between the clinical indicators and the structure of the embryos of 5–6 days of the preimplantation development. The blastocysts with the highest degree of the internal cell mass and the trophoblast formation in combination with a high degree of the expansion (4) give the best results of the clinical pregnancy rate.

Conclusions. When performing vitrification we found out that the stage of the blastocyst development influences their survival and pregnancy rates. The phenomenon of hatching in the embryos of 5–6-day preimplantation development should be regarded as a factor that reduces the success of vitrification.

The aim of research is to study morphofunctional reorganization of the oral mucosa during regeneration of a wound defect using polymer membranes based on a copolymer of vinylidene fluoride with and without tetrafluoroethylene.

Material and methods. The study included 35 white Wistar rats weighed 220–280 g. All animals were divided into three groups: group 1 – intact animals, group 2 – an experimental comparison group, and group 3 – an experimental main group. A wound defect in rats was formed by the excision of the mucosal flap in rats; this defect was overlapped by a polymer membrane in animals of the 3rd group. Histological and macroscopic studies were performed in 3, 7 and 12 days.

Results. More rapid development of the granulated and loose fibrous connective tissue noted already on the 3rd day of the study was recorded in animals of the 3rd group. On the 7th day of the study a 1.5-time decrease in inflammatory infiltrate was recorded in animals of the experimental main group, while in the experimental comparison this indicator decreased in only 1.35 times. Moreover, the formation of the loose fibrous connective tissue in the main experimental group occurred 3.2 times more intensively than in the comparison group. On the 12th day, the specific area of the loose fibrous connective tissue in the experimental main group was 1.4 times larger, and the specific area of scar tissue was 3 times smaller than in the experimental comparison group.

Conclusion. Application of polymer membrane demonstrated a decrease in inflammatory infiltrate and more rapid maturation of the loose fibrous connective tissue compared with the open wound  management. Moreover, there was a significantly smaller formation of the dense fibrous connective  tissue. Thus, it is possible to conclude on the effectiveness of polymer piezoelectric membrane application in the management of oral wound.

Currently, the mortality rate in pediatric population resulted from such diseases as respiratory distress syndrome, pneumonia and infections is extremely high. It cannot be ruled out that this is due to impaired functioning of the children's immune system. The thymus gland appears to be the central organ of immunopoiesis in children, that is why pediatricians pay special attention to thymic hyperplasia. To date, there is no consensus on the nature and clinical significance of the thymic enlargement.

The aim of research was to study morphometric parameters of the thymus gland in children of the first year of life having thymic enlargement.

Material and methods. To analyze the incidence of thymic enlargement in deceased children, the authors selected 764 autopsy protocols of children for the period from 2012 to 2017; of these, 117 were children who died in their first year of life. Autopsies were performed in Saratov Centralized Pediatric Prosectorium. The thymic enlargement in deceased children of the first year of life was detected in 34% (40 cases). Autopsy material of 32 children was selected (15 cases with and 17 cases without the thymic enlargement) for histological examination. The thymic index was calculated to specify correlation between the thymus mass and the age and body weight of a child. Morphometric studies were performed using an mVizo-103 microvisor.

Results. As demonstrated, infectious diseases are a risk factor for the formation of thymomegaly in  children of the first year of life. A morphological study detected that the thymic enlargement occurred  mainly due to the enlargement of the cortical layer with the reduction of the lobule area. The lobule area in the studied group of children reduced by 15%, and the number of lobes bordering in the field of view increased by 50%, respectively to the similar parameters in children of the comparison group.

Conclusion. Thus, infectious pathologies appear to be the most common cause of death in children with the thymic enlargement. The study results support the fact that histological signs of thymomegaly are the increased number of bordering thymic lobes in the field of view and the increased number of immature thymocytes.

The purpose of present work was to characterize morphological alterations of rat hippocampal neurons
after long-term (12-months) consumption of excessive doses of ionic fluoride (F–).

Material and methods. Male Wistar rats were assigned to four groups. Animals from control group were given drinking water with background F– content of 0.4 mg/L, rats from other groups  received the same water with 5, 20 and 50 mg/L (as NaF). The morphology of neurons in CA3 and CA1 hippocampal areas was evaluated after staining of brain slices with toluidine blue according to Nissl’s method.

Results. Long-term intoxication of rats with F– resulted in disorganization of cellular layer and decline in numerical density of pyramidal neurons in CA3 and CA1 hippocampal areas, which most probably indicates the death of a part of the cells. The neurons of both hippocampus zones exhibited such  pathological changes as unequal distribution of Nissl substance, shifting of nuclei to periphery, cytoplasm  vacuolization. Some neurons underwent swelling, other, in contrast, shrunk, spindle neurons  or cells with spiral-like outgrowths were also visualized. In hippocampus of F–-exposed rats, the number of normochromic neurons decreased, but amount of hyperchromic and hypochromic cells increased.

Conclusion. Long-term intake of excessive F– doses by the rats was established to induce dystrophic and necrobiotic changes of pyramidal neurons in CA3 and CA1 hippocampal zones. The revealed pathological processes can be a cause of disturbances in inter-neuronal communications in the hippocampus and lead to development of various neurological and cognitive disorders.

The aim of the study was to identify the features of the macro- and microscopic structure, as well as the cellular composition of the intestinal glands in adults with clinically confirmed total dolichomegacolon and colonoptosis.

Material and methods. On total preparations of the colon obtained from the corpses of persons 42–87 years old, structural changes of the glandular apparatus were studied in cases with total  dolichomegacolon (n=7) and total colonoptosis (n=5), diagnosed postmortem. Microscopic examination was performed on histological preparations stained with methylene blue, with subsequent fixation in a saturated solution of ammonium molybdenum acid, hematoxylin–eosin, and picrofuxin by Van-Gieson. Parametric and nonparametric statistical methods based on the Statistica 6.0 program were used. Data processing included the calculation of arithmetic averages and their errors.

Results. The analysis of cell composition of the colon epithelium in total dolichomegacolon revealed a progressive decrease in the number of glands in the proximo-distal direction from 22.5±1.1% in the caecum to 37±0.9% in the rectum. Besides, the length of the glands decreased, on average by 26.5±0.8% for all parts of the large intestine without a pronounced gradient from the caecum to the rectum. According to the decrease in length of the intestinal gland, there was a decrease in the number of epithelial cells forming its walls with a maximum in the descending colon – a decrease of 21.4±1.1%. Structural changes in total colonoptosis were similar in nature and did not significantly differ in large values of reduction of the glandular apparatus. Due to analyzing the cellular component of the colon glands, a multidirectional character of changes in the composition of the glands was noted: a decrease in the percentage of absorption cells on average by 21.1±0.8% and an increase in the proportion 
of goblet cells by 33.4±1.2% on average, due to a compensatory increase in the amount of mucus in the studied pathological conditions.

Conclusion. Actual data on the decrease in the number and change in the structure of the glandular apparatus of all parts of the large intestine of adult people against the background of clinically verified total dolichomegacolon and colonoptosis were obtained. The nature of the identified structural and  functional rearrangements is of great importance both for proctological practice and for theoretical and practical medicine in general.

The aim of the study was to identify characteristics of the neuron reactions and macroglial cells in the limbic cerebral cortex after ethanol poisoning, alcohol withdrawal and chronic alcohol intoxication in humans.

Material and methods. The study included Nissl stained histological sections in the area 24 b in healthy people (n=5), in people died from ethanol poisoning (in the period of ethanol resorption, n=5)  and in people during alcohol withdrawal (at the end of ethanol elimination, n=5) having early signs of an alcohol disease. The number and proportion of neurons in identification groups (unmodified/low- modified, hypochromic, shriveled hyperchromic, “shadow cells”), the number of satellite cells and the ratio of satellite cells to the number of unchanged neurons (glio-neuronal index), the average area of the neuron bodies was calculated on horizontal sections of the anterior limbic cortex 1 mm2 in area.

Results. The study proposed to distinguish between acute (or transient), delayed and chronic response of neuronal cells. The acute reaction that develops during ethanol poisoning is expressed by acute swelling of neurons and results from a combination of altering factors: the toxic effects of ethanol and the overproduction of catecholamines. The acute reaction is more pronounced in the dopaminergic layer  III of the anterior limbic cortex than in layer V. It is transient, since in the period of alcohol withdrawal (ethanol elimination) it regresses and becomes delayed. The latter is to increase and dominate the  proportion of atrophic reduced in the size of lowmodified and atrophic wrinkled neurons, increased phagocytic activity of dead neurons, as well as the development of compensatory-adaptive reaction of the satellite form of glia, the most pronounced in layer III. Delayed reaction of neurons is due to the weakening and cessation of acute effects of toxicants; as a result, the signs of previous long-term  intoxication effects of ethanol, its toxic metabolites and increased concentrations of catecholamines, hich caused cell atrophy, come to the fore. Chronic cell response is expressed by a significant increase in the proportion of neurons-"shadows", the number of macroglial cells and atrophic wrinkling of neurons. In people with early manifestations of an alcohol disease, signs of acute neuronal damage are combined with signs of atrophic ones. 

The aim of the study was to compare features of fatty degeneration of the thymus in humans and vertebrate animals living in the natural and anthropogenic environment.

Material and methods. This was a comparative morphological study. For the first time, the methods of light microscopy were applied to compare the thymus in humans and vertebrates belonging to four classes: Amphibia, Reptilia, Aves, Mammalia.

The results of the study evidence the absence of fatty degeneration of the thymus in the vast majority of animals living in the natural environment. Owing to the specific features of biology, an insignificant amount of adipose tissue (0.38±0.041%) in the area of interlobular septa appears only in the thymus of a white-breasted hedgehog. There is no fat replacement of the lymphoid tissue of the thymus in the hedgehog, since fat cells remain separated from the lymphocytes and reticulo-epithelial stroma by the connective tissue fibers of the interlobular septa. In vertebrates under vivar conditions, as well as in humans, the severity of fatty degeneration increases tenfold due to the effects of physical inactivity. It was found that in the second period of maturity, the area occupied by the adipose tissue in the thymus of mature American mink reaches 3.07±0.68%, in an outbred rat – 28.4±4.1% and in humans – 39.15±6.65%. The early terms of the onset of fatty degeneration and the greatest severity of this phenomenon in the thymus of a human are associated not only with the influence of hypokinesia and excessive intake of calories, but also due to a complex of other adverse effects that are found in abundance in an anthropogenic environment.

Conclusion. Thus, fatty degeneration is not an obligate effect of age-related involution of the lymphoid system, but most likely results from the influence of specific conditions of existence.

Numerous studies on animal models endow prolactin with multiple functions, both physiological (reproduction, lactation, growth, metabolism, transport and electrolyte behaviour) and pathological (immunity and carcinogenesis). Prolactin is an acidophilic cells hormone of the anterior pituitary gland. For the past decade, there have been many discoveries regarding the functions of prolactin and its receptor (PRL-R). Prolactin has its effect by binding to membrane-bound receptor isoforms, known as long-form and short-form receptors. The PRL-R receptor is expressed in various tissues, such as the mammary gland, prostate gland, ovaries, immune system cells, adipocytes, liver, etc. One of the most well-known functions of prolactin is to stimulate the proliferation and differentiation of breast cells necessary for lactation. Animal models have provided information on the biology of prolactin proteins and give convincing evidence that each prolactin isoform has independent biological functions. It is important to remember that excessive secretion of this hormone is associated with such symptoms as hypogonadism and infertility. Today, up to 40% of all female infertility cases are caused by hyperproduction of prolactin. One of the infertility causes is  a combination of hyperprolactinemia and external genital endometriosis, which is currently not well studied. It remains relevant to determine the role of prolactin and dopamine in the pathogenesis of  infertility in women with external genital endometriosis and the possibility of using dopamine agonists in the treatment of this disease. This review focuses on the role of prolactin and its receptors in the pathogenesis of infertility associated with endometriosis.

The paper provides a brief data overview of the national and the foreign recent decades literature on various aspects of the morphofunctional organization of the greater omentum in the physiological and various pathological states of the organism (in the process of morphogenesis, in the conditions of age-related alterations, under various experimental exposures, as well as in the postoperative transformations after surgical interventions due to inflammatory and tumor processes). The data on morphofunctional organization of the greater omentum main tissue components (mesothelium, adipose and lymphoid tissues) have been analyzed and summarized.

Detection of blood vessels and assessment of their functional state is an acute issue of modern histology.

The aim of the study was to develop a double immunofluorescence staining technique to study different types of blood vessels in the rat lung.

Material and methods. The study included samples of the right and left lungs of sexually mature (3–5 months) male Wistar rats (n=5). Rabbit polyclonal antibodies to von Willebrand factor (Agilent, USA) and mouse monoclonal (clone 1A4) antibodies to smooth muscle α-actin (Agilent, USA) were applied to detect blood vessels. Sections were analyzed using the method of confocal laser microscopy.

Results. In the study the authors designed a double immunofluorescence protocol, which allows highly selective detection of blood vessels of various types in the rat lung. The use of von Willebrand factor as one of the markers facilitates blood vessel endothelium identification. Application of the second marker – smooth muscle α-actin – allows identifying a layer of smooth myocytes; and their structural features provide detection of the blood vessel type (whether it belongs to the arterial or venous bed). The proposed protocol is characterized by good reproducibility and allows producing high quality drugs. Due to the high specific immunoreactivity of the antibodies used, the stage of thermal unmasking of antigens can be removed from the staining protocol, which makes it less time-consuming, shortens the preparation time of the sections and ensures their better preservation. The use of von Willebrand factor and smooth muscle α-actin as markers allow evaluating not only the structure, but also the functional status of the studied blood vessels. This provides application of the proposed method for scientific and
clinical diagnostic studies.

This article is the first part of two articles on Nikolay Ivanovich Pirogov. In this article we will discuss how Pirogov developed in his early professional career his unique scientific attitude toward medical problems. He extended this scientific view already before his appointment as Professor of Applied Anatomy and Hospital Surgery at the Medical-Surgical Academy and chief surgeon of the Second Military Landforce Hospital (with 1000 beds) in 1841. After his resignation as Professor in 1860 and during his retirement he used his views and skills towards the management of mass casualties during wars or others, which eventually developed into the International Red Cross.
In the second article “Nikolay Ivanovich Pirogov as an innovator in anatomy, surgery, and anaesthesiology.” we will highlight his professional career as an anatomist, surgeon and anaesthesiologist. The authors of these two parts want to emphasize that these two articles are an extract from previously published extensive articles related to Nikolay Ivanovich Pirogov. You can find these articles in the reference list under  the name of the first author [20–25].