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The study of the embryonic development of the pancreas gives the opportunity to understand the mechanisms of organ regeneration in case of various pathologies. Worldwide research works, studying histo- and organogenesis of human pancreas, are based on data, received from model animals. Numerous processes of pancreatic development take several hours and remain unclear because white laboratory mouse has short gestation period. Spiny mouse (Acomys) has the prolonged prenatal period and can be a convenient model to study the stages of histo- and organogenesis of the pancreas. The review analyzed similarities and differences in the structure of human pancreas, white laboratory mouse and spiny mouse, the features of prenatal histo- and organogenesis of the pancreas, which should be considered in conducting and interpreting results of fundamental research, and possibility of using of spiny mice as a model animal to study embryonic development and pathology of the pancreas.

The article presents data on the regeneration of the auricle tissues of Acomys cahirinus mice (n=12) and Balb/c mice (n=12). Two experimental models were used: a full-thickness perforated defect with a diameter of 3 mm and subtotal removal of the auricle. Macrophotography and histological examination using general histological stains and detection of elastic fibers were performed after 2, 5, 15, 21, 30, 60, 90, and 120 days. It was found that regeneration in Acomys is more pronounced, which manifested itself in the complete elimination of the defect by 30-60 days in contrast to the control (Balb/c). A feature of this was less pronounced post-traumatic inflammation in Acomys mice. It was established the growth of a full-fledged auricle in case of its surgical removal. An important feature of regeneration in this case is the development of new cartilage tissue both from the edges of the original cartilage and developed in the form of separate islands of cartilage tissue. The newly formed cartilage was characterized by high cel-lularity, a smaller volume of the matrix, in the structure of which elastic fibers were formed. However, it should be noted that within 30-60 days. the recovery process, apparently, is not completed, the formed tissue regenerate enters the remodeling phase.

A number of sarcolemma proteins are responsible for muscle fiber repair. Dysferlin encoded by the

The novel coronavirus infection named COVID-19 was first detected in Wuhan, China, in December 2019, and it has been responsible for significant morbidity and mortality in scores of countries. At the time this article was being written, the number of infected and deceased patients continued to grow worldwide. Most patients with severe forms of the disease suffer from pneumonia and pulmonary insufficiency; in many cases, the disease is generalized and causes multiple organ failures and a dysfunction of physiological systems. One of the most serious and prognostically ominous complications from COVID-19 is coagulopathy, in particular, decompensated hypercoagulability with the risk of developing disseminated intravascular coagulation. In most cases, local and diffuse macro- and microthromboses are present, a condition which causes multiple-organ failure and thromboembolic complications. The causes and pathogenic mechanisms of coagulopathy in COVID-19 remain largely unclear, but they are associated with systemic inflammation, including the so-called cytokine storm. Despite the relatively short period of the ongoing pandemic, laboratory signs of serious hemostatic disorders have been identified and measures for specific prevention and correction of thrombosis have been developed. This review discusses the causes of COVID-19 coagulopathies and the associated complications, as well as possible approaches to their early diagnosis, prevention, and treatment.

A tumor of the uterus, consisting of smooth muscles, is called myoma and fibroids, and in practice, the terms are used synonymously. Myoma of the uterus is a common disease in women of childbearing age. The frequency of its detection without regard to age is 2.45%. With age, its prevalence increases and reaches 8.31% by the age of 50. The estimate of the final probability of contracting uterine fibroids in the population throughout life is 9.7%. According to sectional data, uterine fibroids, including small nodes, occur in 20% of women. In 50% of cases, these tumors are manifested by clinically pronounced disorders that lead a woman to a doctor.

Aim. To assess of adaptive immunity of the duodenal mucosa in neonates with sepsis. Methods. A study of duodenal biopsy specimens obtained during duodenoscopy from neonates who had signs of suspected ulcerative lesions of the digestive tract. Five of them were obtained from infants with clinical and laboratory signs of neonatal sepsis (NS), two from infants without sepsis (comparison group). Immunohistochemical staining was performed using the Novolink Polymer Detection System imaging system with commercial antibodies to CD4, CD8, CD20 and Bcl-2, and the CSAII Biotin-free Tyramide Signal Amplification System imaging system with commercial antibodies to caspase-3 and caspase-9 in accordance with the manufacturers instructions. Results. It was found that the number of CD4+ T-lymphocytes of the duodenal mucosa in neonatal sepsis group in 4 of 5 infants did not differ from the control group. The number of CD8+ lymphocytes in neonates with sepsis in 3 of 5 cases was even higher than in the control group. The number of CD20+ B-lymphocytes in 4 infants with sepsis was significantly less compared with the control. Activation of apoptosis in mucosal cells was detected, which was manifested by a large number of caspase-3-positive cells (in 4 of 5 cases) in comparison with the control group. The number of caspase-9-positive cells in the studied groups was almost equal. A substantial decrease in the number of Bcl-2-positive mucosal cells in all 5 infants with sepsis was noted as compared with the control indicators. Conclusion. The study revealed moderate immunosuppression in the duodenal mucosa in neonates with sepsis, manifested by low values of CD20+ B-lymphocytes in the absence of a significant decrease in the number of CD4+ and CD8+ T-lymphocytes. The detected moderate activation of apoptosis processes against the background of reduced antiapoptotic potential creates the conditions for a possible translocation of the intestinal microbiota into the bloodstream.

Different transcription factors, which are synthesized at different stages of cell differentiation, are often considered markers of p-cell precursors. One of these transcription factors is MafA, the role of which is not fully understood. According to one hypothesis, it activates insulin gene expression in the differentiating p-cells. According to another, this factor is only necessary for the regulation of insulin secretion by already differentiated p-cells. In favor of the latter hypothesis, we showed that MafA is not expressed in the immature p-cells during the prenatal development of the human pancreas. In order to finally determine whether MafA is a marker of differentiating cells or it is synthesized in already mature p-cells the aim of our investigation was the analysis of dynamical changes of MafA-positive cell population and C-kit-positive endocrinocyte precursors in Langerhans islets during experimental diabetes in rats. The study was performed on male Wistar rats (250-300g body weight) which were intraperitoneally injected with alloxan. Animals were sacrificed 1,2, 7, 14, 21 days of the experiment for the morphological analysis of pancreas. Paraffin sections of pancreas were stained immunohistochemically with antibodies against MafA, C-kit, insulin and glucagon. The maximum number of MafA-positive cells in the islets was found during normal prenatal development of pancreas. At all stages of the experimental diabetes the number of MafA-positive cells in the islets decreased, wherein the number of insulin-positive cells in the islets increased by the end of the first and third weeks of the experiment. It was also established that in experimental diabetes, changes in populations of MafA- and C-kit-positive cells occur in different ways. Thus, the results of our research showed that MafA cannot be considered as a marker of progenitor cells and is expressed only in the mature cells of the Langerhans islets, that confirms our previous data obtained during the study of prenatal development of human pancreas.

We studied the autopsy material obtained from 7 children who died in the neonatal period in order to evaluate the composition of lymphocytes of the intestinal mucosa against the background of morphological changes in the tissues of the gastrointestinal tract in newborns with sepsis. The main group consisted of 4 children with neonatal sepsis, the control group – of 3 newborns who died from other causes. The research material included the specimen of the small and large intestine.Results. Small intestine: it was found that there were less CD4 + lymphocytes in the small intestinal mucosa in the group of children who died from neonatal sepsis in 75% of cases than in the control group, but this difference was not statistically significant (p=0.1). There were no differences in the number of CD8 + and CD20 + cells in the studied groups. Large intestine: the number of CD4 + lymphocytes of the mucous membrane of the colon was greater in the main group of children than in the control group (p=0.03). An increase in the number of CD4 + cells was registered in 3 of 4 cases of neonatal sepsis. The number of CD8+ and CD20+ lymphocytes in the studied groups was the same (р>0.05).Conclusion. The increase in T-lymphocytes CD4+ in the mucous membrane of the large intestine is probably connected with the antigenic stimulation of opportunistic intestinal bacteria. We found no morphological signs of the suppression of the cells of adaptive immunity associated with the intestinal mucosa.

Dysferlinopathies are a group of muscular dystrophies with autosomal-recessive inheritance caused by mutations in DYSF gene. Dysferlin is a 237 kDa transmembrane protein responsible for reparation of the sarcolemma. It has calcium-sensitive C2 domains and after dysferlin binding with calcium ions the first one activates vesicles fusion and patch mechanism repair. There are number of knockout animal strains with dysferlin gene mutations. Bla/J mice have the ETn retrotransposon inserted in intron 4 of the DYSF gene of wild-type mice - C57Bl/6. The pathogenesis ascertainment of dysferlinopathies is important not only for revealing of physiological function of dysferlin, but its deficiency influence on reparative regeneration of skeletal muscles. In this paper the description of main pathohistological processes in skeletal muscle that take place in mice with dysferlinopathy after acute myotoxic injury is present. This article reviews quantitative evaluation of main pathomorphological processes in reparative regeneration: alteration (necrotized muscle fibers ratio), proliferation (Ki-67-positive myonuclei ratio), differentiation (mean cros-sectional area, percentage of centrinucleated muscle fibers, myo-genin-positive nuclei ratio, slow/fast muscle fibers ratio). It was identified that dysferlin-deficient mice have increased alteration level with more necrotized muscle fibers (35,1% (29,4%; 42,9%) in Bla/J vs. 25,8% (17,9%; 37,4%) in C57Bl/6 on 2 day after alteration, p

Coronary artery disease remains one of the primary healthcare problems due to the high cost of treatment, increased number of patients, poor clinical outcomes, and lack of effective therapy. Though pharmacological and surgical treatments positively affect symptoms and arrest the disease progression, they generally exhibit a limited effect on the disease outcome. The development of alternative therapeutic approaches towards ischemic disease treatment, especially of decompensated forms, is therefore relevant. Therapeutic angiogenesis, stimulated by various cytokines, chemokines, and growth factors, provides the possibility of restoring functional blood flow in ischemic tissues, thereby ensuring the regeneration of the damaged area. In the current study, based on the clinically approved plasmid vector pVax1, multigenic constructs were developed encoding vascular endothelial growth factor (VEGF), fibroblast growth factors (FGF2), and the DsRed fluorescent protein, integrated via picornaviruses’ furin-2A peptide sequences. In vitro experiments demonstrated that genetically modified cells with engineered plasmid constructs expressed the target proteins. Overexpression of VEGF and FGF2 resulted in increased levels of the recombinant proteins. Concomitantly, these did not lead to a significant shift in the general secretory profile of modified HEK293T cells. Simultaneously, the secretome of genetically modified cells showed significant stimulating effects on the formation of capillary-like structures by HUVEC (endothelial cells) in vitro. Our results revealed that when the multicistronic multigene vectors encoding 2A peptide sequences are created, transient transgene co-expression is ensured. The results obtained indicated the mutual synergistic effects of the growth factors VEGF and FGF2 on the proliferation of endothelial cells in vitro. Thus, recombinant multicistronic multigenic constructs might serve as a promising approach for establishing safe and effective systems to treat ischemic diseases.

The study assessed reactivity of stromal-vascular skeletal muscle differons to acute chemical injury. Dysferlin-deficient Bla/J mice and the wild-type С57BL/6 mice were intramuscularly injected with 100 μl of 0.5% procaine solution. The middle segment of gastrocnemius muscle was taken on postsurgery days 2, 4, 10, and 14 for routine histological examination. To evaluate proliferation and vascularization, the paraffin sections were stained immunohistochemically with antibodies to α-smooth muscle actin and Ki-67. The connective tissue was stained according to Mallory. The study revealed diminished proliferative activity of stromal-vascular differons and decreased vascular density in muscles of Bla/J mice. Thus, mutations in the DYSF gene coding dysferlin down-regulate the reparation processes in all differons of skeletal muscle.

Global changes in recent decades, caused by scientific and technological breakthroughs, which are characterized as a genomic revolution and the fourth industrial revolution, raise new pressing issues both for society as a whole and for public health. The latter can not exist and develop without a qualitative, and most importantly, modern medical education, in which significant changes are also taking place. In particular, the transition to standards by the World Federation of Medical Education (WFME) and the Association of Medical Education in Europe (AMEE) - «International Standards of Medical Education for Improving the Quality of Health» (Copenhagen, March 15-19, 2003). In this article, based on the analysis of trends in the development of health care and medical education, possible options for correcting approaches in the teaching of morphological disciplines (normal anatomy, histology, pathology) in medical universities are considered.