Acute herpes simplex virus infection in pregnant women results in intrauterine infection of the fetus in 45–50% of cases, thus being the cause of septic complications and severe somatic and neurological disorders in the newborn.The aim of the study was to investigate the placentas of new mothers with newly diagnosed herpes simplex virus type 2 infection (HSV-2) using histological and immunochemical methods.Material and methods. This histological study included 10 placentas of new mothers after operative delivery by caesarean section with newly diagnosed HSV-2 infection. The comparison group (control) consisted of 10 placentas of women with a physiological pregnancy. Histological sections of the placenta were stained with hematoxylin and eosin, Giemsa's solution and Picro-Mallory staining. Identification of the pro- and antiinflammatory phenotype of macrophages (CD68, CD163), subpopulations of CD4 and CD8 lymphocytes, TLR4 receptor expression was performed by immunohistochemical method using specific antibodies. Quantification of the cell population and TLR4 receptors was performed morphometrically. The data obtained were statistically analysed using MS Excel (2016) and SPSS Statistics 17.0.Results. Morphological manifestations of acute herpes simplex virus infection were combined inflammatory and compensatory in nature in the third trimester of pregnancy. The histological picture of the fetal part of the placenta demonstrated a decreased number of M2 (antiinflammatory) macrophages and an increased number of M1 (pro-inflammatory) macrophages. The imbalance between CD163+ and CD68+ profiles of placental macrophages with the numerical predominance of the latter evidenced a pronounced cellular immune response; this, in turn, was supported by intense TLR4 immunopositive staining of the fetal part of the placenta. There was perivillous fibrin deposition of varying degrees, villus agglutination, and necrosis of trophoblast cells associated with a relatively small population of CD4+ and CD8+. Villitis of viral etiology was characterized by destructive infiltration of maternal CD8+ T-lymphocytes penetrating the chorionic villi, combined with activated macrophages in the villi of the fetal part of the placenta. Modifications in the proportion of immune cells during HSV-2 infection supported cytotoxic and autoimmune reactions in the placenta in response to HSV-2 introduction.Conclusion. The results obtained evidence the development of a pronounced immunopathological process in the tissues of the fetal part of the placenta, which results in the decreased protective and compensatory properties of the placenta and increases risk of perinatal complications.

Depleted uranium has high cumulative capacity and, upon entering the human body, exerts radiological and chemotoxic effects. The aim of the study was to immunohistochemically evaluate the activity of caspase-3 and -9, as well as the response of stromal mast cells in the parotid salivary gland at 1, 3, and 6 months after a single oral administration of an aqueous solution of depleted uranium oxides. Material and methods. The experiment was conducted on 180 outbred male white rats divided into 6 groups (3 experimental and 3 control). Animals in the experimental groups received a single oral dose of depleted uranium (0.01 mg/100 g body weight). The parotid glands of control and experimental groups were examined after 1, 3, and 6 months. Organs were fixed in 10% neutral formalin, followed by histological staining (hematoxylin-eosin), immunohisto- chemical detection of caspases-3 and -9, and identification of mast cells (tryptase⁺, ChAE⁺). Results. At 1 month after depleted uranium administration, ultrastructural changes in acinar cells (vacuolization, protein dystrophy) and stromal inflammatory reactions (edema, vascular congestion) were observed. Immunohistochemical analysis revealed a significant increase in caspase-9 activity in the parenchyma, while caspase-3 expression increased significantly only by the 3rd month. By the 6th month, caspase-induced apoptosis in the parenchyma decreased but persisted in ductal cells. Mast cells showed peak activity at 1 month (increased tryptase⁺ and ChAE⁺ cells), followed by a decline in functional activity by the 6th month. Conclusion. Oral intake of depleted uranium oxides induces a biphasic response in the parotid gland: an early phase (1 month) involves acute damage with activation of the mitochondrial apoptosis pathway (caspase-9) and mast cell degranulation, while a late phase (3–6 months) transitions to chronic inflammation with predominant caspase-3-dependent apoptosis in the ducts. These findings enhance the understanding of depleted uranium toxicity mechanisms, highlighting the role of stromal-parenchymal interactions in long-term salivary gland damage.

Introduction: Progestogen-based drugs have anti-ischemic, antispasmodic, and immunomodulatory effects. Therefore, studying the effect of micronized progesterone (MP) on the inflammatory process in the placenta is of great importance. Materials and Methods: Four observation groups were formed: Control Group 1 (CG1, n=6) – intact rats; Control Group 2 (CG2, n=6) – pregnant rats with simulated placental insufficiency; Experimental Group 1 (EG1, n=7) – rats with simulated placental insufficiency that received MP dosage 20 mg/day; Experimental Group 2 (EG2, n=7) – rats with simulated placental insufficiency that received MP dosage 40 mg/day. An analysis of the placenta, anthropometric parameters of the fetuses, and physical development parameters of the offspring was conducted. Histological and immunohistochemical analyses of the placentas were performed. Results and Discussion: Miscarriage was observed in 16% of animals from CG2, which did not receive MP therapy, compared to rats from CG1. In intact CG1 and EG1 rats, the course of pregnancy, parturition, and developmental parameters of the pups were within physiological norms. In rats from EG2, the course of pregnancy and parturition, the condition of rat pups did not differ from the physiological norm; however, one rat developed convulsions during birth. Immunohistochemical analysis revealed reduced inflammatory manifestations in the placenta of rats treated with MP, compared to animals from the control group that did not receive pharmacological correction. Conclusion: Under experimental conditions, MP can prolong pregnancy to physiological norms and have a positive effect on the physical development of the offspring.

The effect of altered gravity on the digestive system is one of the challenging issues in space biology and medicine. The study of the effect of weightlessness on the mast cell (MC) functioning in the gastrointestinal organs is determined by their multifunctionality and participation in the developing adaptive and pathological processes.   The aim of the study was to investigate the morphofunctional state of MCs in the stomach membranes of Wistar rats during 14 days of ground-based simulated weightlessness conditions and in a 3-day recovery period.   Material and methods. The experiment involved 3 groups of Wistar rats: control, experimental – exposed to antiorthostatic suspension – and a 3-day-recovery group, 7 animals each, respectively. Identification of MCs was carried out using May-Grunwald staining with additional staining with Giemsa solution and immunohistochemical tryptase detection. The results obtained were statistically processed with SPSS 13 using parametric and non-parametric criteria.   Results. A significantly increased number of metachromatic MC population was found only in the mucosa in animals of the antiorthostatic suspension and 3-day-recovery groups compared to the vivarium control. There was a sharp decrease in degranulating forms of MCs in the submucosalcoat in animals of the 3-day-recovery group compared to the control. A significantly increased number of degranulating forms of MCs was revealed in the muscle membrane in animals of the antiorthostatic suspension group. Immunohistochemical staining of MCs with antibodies to tryptase, in contrast to staining for metachromasia, allowed identifying a significant representation of tryptase-positive cells in the gastric mucosa in animals of the 3-day-recovery group. Conclusion. The results obtained support gravisensitivity of certain structural components of the stomach, and also evidence MC and their secretome participation in the developing adaptive responses to the effects of altered gravity both at the cellular and tissue levels.

Spaceflight has crucial effects on living organisms, primarily due to weightlessness, which causes essential morphofunctional changes in the tissues of almost all body systems. Smooth muscle tissue is one of the main system-forming components of the gastrointestinal tract, which makes its study particularly relevant to space gastroenterology. Integrins are cell adhesion receptors expressed in practically all cell types, including smooth muscle cells. By mediating interactions with the extracellular matrix and intercellular signaling, smooth muscle cell integrins actively participate in adaptation to microgravity conditions. However, this aspect of smooth muscle tissue function has not been addressed in space gastroenterology until now. The aim of the study was to investigate the expressions of integrins alpha-5, alpha-2, and alpha-1 expression in smooth myocytes of the gastric and jejunal muscular layer in Mongolian gerbils (Meriones unguiculatus) after a 12-day spaceflight, which was part of the Foton M-3 project. We detected a slight increase in integrin alpha-1 expression, a trend toward decreased integrin alpha-2 expression, and a significant decrease in integrin alpha-5 expression in the gastric and jejunal muscularis propria in Mongolian gerbils from the spaceflight group, which may indicate weakened interactions between cells and the extracellular matrix and potentially lead to reduced smooth muscle contractility. Research on the fundamental role of integrins in the development of the digestive system adaptive mechanisms to zero-gravity conditions may be useful in developing preventive measures to mitigate the risk of gastrointestinal smooth muscle hypotrophy and maintain the health of astronauts during their professional activities aboard the ISS.