Bulletin of Experimental Biology and Medicine最新文献

Boundary cap cells are a population of multipotent stem cells that have great potential for the use in the treatment of damaged nervous system. We studied the patterns of distribution of the gap junction protein connexin-43 (Cx43) in boundary cap cells of the ventral root of the spinal cord of rat embryos (E12-E20; n=40). It was found that Cx43 is expressed in ventral boundary cap cells at all stages of its existence during embryogenesis. At the early stages of prenatal development, the cytoplasmic distribution of Cx43 in the boundary cap cells predominates; at the later stages, Cx43-immunopositive punctate structures are identified. These puncta represent gap junction plaques between the cells. It can be assumed that during the early embryogenesis, Cx43 regulates the main histogenetic processes in boundary cap cells and only in the later stages of prenatal development, Cx43-mediated communications are formed between boundary cap cells.

In adult male mice with high (HR) and low (LR) resistance to hypoxia, on days 21 and 28 after subcutaneous injection of Lewis lung carcinoma cells, a morphological and morphometric study of the primary tumor nodes and metastases in the lungs was carried out. Peripheral blood parameters and subpopulation composition of blood cells, the expression of genes responsible for the development of inflammation (Nfkb, Il1b, Il6, Tnfa, Il10, and Tgfb) and the response to hypoxia (Hif1a) in the liver were also assessed. The tumors were detected in 84.6% HR and 91.7% LR mice. The mitotic index of tumor cells in the subcutaneous nodes of HR animals was statistically significantly higher. The metastases area on days 21 and 28 did not differ. In animals of both groups, an increase in the absolute number of leukocytes, monocytes, and granulocytes, a decrease in the hemoglobin content and the absolute number of erythrocytes in the peripheral blood were detected on day 28 of the experiment. Only in LR animals, an increase in the absolute number of CD11b⁺ monocytes was found on day 28 of the experiment in comparison with the control group. The expression of Hif1a, Nfkb, Tnfa, and Tgfb genes in the liver of LR animals was higher than in HR mice, which attested to more pronounced systemic inflammatory response. These data should be taken into account when developing new approaches for the treatment of neoplastic disorders.

The effectiveness and safety of two types of samples based on a biocompatible polymer material made of methacrylic oligomers (Reperen) as a potential antiadhesion pericardial barrier were evaluated in in vitro and in vivo experiments. Two kinds of samples, reinforced with a polyamide mesh and without reinforcement, were used. In in vitro experiments, no adhesion and aggregation of human fibroblasts to the test samples were detected. In in vivo experiments, the samples implanted to rats into the thigh muscles were easily separated from the surrounding tissues 1, 2, and 3 weeks after implantation, being weakly fixed only in the area of the edges. Histological examination at week 2 after implantation revealed no differences between the experimental and control groups. At week 1 and 3, fibrosis and inflammation were more pronounced in animals of the control group (with simulated implantation). The properties demonstrated by both samples of Reperen barriers (with and without polyamide mesh reinforcement) in vivo and in vitro allow considering them as a potential antiadhesion pericardial barrier for clinical use.

Screening of cell surface markers of three glioma cell lines (astrocytoma 1321N1, glioblastoma T98g, and glioblastoma astrocytoma U373 MG) was performed. Glioma cells expressed common mesenchymal cell markers, although the expression levels varied between the cell lines. The expression of proneural markers and glioma cancer stem cell markers was very low and also varied. Induction of differentiation towards the mesodermal cell lineages showed effective adipogenic and osteogenic differentiation for only the U373 MG cell line, while the 1321N1 and T98g lines demonstrated weak adipogenic potential and failed to undergo osteogenic differentiation. The obtained results point to the intratumor phenotypical heterogeneity of cells in gliomas and to the differences between the three studied types of gliomas with regard to the content of cells with mesenchymal phenotype.

We studied the effect of bone marrow cells (BMC) and nanosecond repetitively pulsed microwaves (RPMs, 10 GHz, pulse duration 100 nsec, pulse repetition rate 8 Hz, peak power flux density (pPFD) 140 W/cm²) on the regeneration of thermally damaged skin in rats. The combined use of BMC and RPMs accelerates separation of an eschar with its complete rejection on day 14 of the experiment. Histological analysis demonstrated a statistically significant increase in the relative area of the granulation tissue and thickness of newly formed epidermis in the group with combined exposure. Combined therapy ensured completion of wound epithelialization in 100% of rats by day 30 of the study.

The tissue preparations of the pelvic veins obtained during laparoscopy were examined. The expression of markers of proliferation (Ki-67), apoptosis (p53), and angiogenesis (CD31, CD34), as well as estrogen and progesterone receptors in women with pelvic varicose veins was assessed by the immunohistochemical method. A decrease in the median expression of the proliferation marker (Ki-67) and estrogen and progesterone receptors and simultaneous increase in the expression of apoptosis marker (p53) and activation of angiogenesis processes (markers CD31 and CD34) were observed with increasing the severity of the disease. These data extend our understanding of the pathogenetic mechanisms of pelvic varicose veins and contribute to the development of methods of pathogenetically based targeted therapy.

The changes in astrocytes and their role in the development of brain diseases can be identified by morphological analysis of tissue specimens, in particular, by immunohistochemical detection of glial fibrillary acidic protein (GFAP). The study presents analysis of GFAP expression in white matter astrocytes of deceased newborns depending on the duration of the postmortem period. Autopsy material of the brain tissue obtained from 48 deceased newborns was divided into 8 groups depending on the duration of the postmortem period. Immunohistochemical analysis was performed with antibodies to GFAP in tissue samples taken from the superior and inferior brain areas relative to the position of the body stored before autopsy. The area of GFAP+ staining per field of view was determined in the white matter using an image analysis system. Morphometric analysis revealed a decrease in the mean values of the area of GFAP+ staining, i.e. the number of fibrotic astrocytes and their processes decreased with increasing the duration of the postmortem period. The mean areas of GFAP+ staining in the superior and inferior areas of the white matter did not differ significantly between the groups. The identified changes reflect the development of nonspecific postmortem changes which should be considered when taking tissue samples for molecular biological studies and in differential forensic diagnosis with lifetime lesions and diseases.

The functioning of the ventricular myocardium in hypertrophic cardiomyopathy (HCM) under high hemodynamic load leads to depletion of its resources and is associated with the risk of developing a dilated stage. In patients with HCM, the cardiomyocytes of the interventricular septum are hypertrophied, the proportion of cardiomyocytes in which myofibrils constitute less than 50% of the sarcoplasm volume increases with increasing the cardiomyocyte length and correlates with echocardiographic signs of left ventricular obstruction. These cardiomyocytes are characterized by ultrastructural signs of synthetic activity. In the myocardium of patients with HCM, single cardiomyocytes with "critical" loss of myofibrils and nonspecific degenerative changes corresponding to the picture of irreversible changes in the cardiomyocyte ultrastructure were revealed. The presence of cardiomyocytes with this ultrastructural phenotype is an early marker of exhaustion of the compensatory capabilities of the myocardium in HCM.

Epithelial progenitor cells of the primitive pancreatic ducts differentiate in 3 directions, which is accompanied by changes in cell phenotype. We analyze the distribution of the pancreatic and duodenal homeobox 1 (PDX1) in the epithelial cells of pancreatic ducts during the prenatal development in order to determine the potential use of this marker as an indicator of pancreatic cell maturation. Pancreatic autopsies from human fetuses (gestation weeks 17-23) were examined by immunohistochemical methods. In general, PDX1 was detected in the epithelial cells that are involved in various morphogenetic processes related to the growth and branching of the fetal pancreatic ducts. The intensive positive reaction to PDX1/cytokeratin 19 indicates immature (progenitor) polypotent ductal cells.

We studied morphofunctional features of human platelets exposed in vitro to low-pulse laser radiation (LPLR) with different wavelengths. Platelet-rich plasma (PRP) was irradiated at wavelengths of 635, 488, and 355 nm. LPLR with λ=635 nm and 1 W power after 10 min caused degranulation of many platelets, formation of small platelet conglomerates, and accelerated platelet adhesion on glass. LPLR with λ=635 nm and 2 mW and LPLR with λ=488 nm did not cause significant changes in the morphofunctional platelet status. LPLR with λ=355 nm induced massive platelets' deformation, sharp decrease in their morphofunctional status without activation.