The effect of Escherichia coli ZP strain with a conjugation-based colicin E7 delivery on growth performance, hematological, biochemical, and histological parameters, gut microbiota, and nonspecific immunity of broilers.

The Escherichia coli ZP strain (ZP) was constructed based on the known probiotic E. coli strain Nissle 1917. It was genetically modified to carry the colicin E7 synthesis gene encoding DNase on a conjugative plasmid and the colicin E7 immunity gene in the chromosome. The aim of this study was to evaluate the effects of the daily ZP per oral administration (5 × 108 or 5 × 1010 CFU per bird) on the growth performance, hematological, biochemical, histological parameters, gut microbiota, and nonspecific immunity of the 4-24 days old broilers. The ZP administration increased the abundance of genera Bacillus, Butyrivibrio, and Clostridium and did not influence the weight gain of 4-16 days old broilers. The biochemical parameters were within normal ranges for poultry in experimental and control groups. The ZP administration had no effect on the erythrocyte numbers, hemoglobin and immunoglobulin Y concentrations, but significantly increased the serum lysozyme concentration, leukocyte numbers, and reactive oxygen species production by phagocytes compared with the control group. It did not cause inflammatory changes in intestinal mucosa, Peyer's patches, and spleen. Thus, the ZP had no detrimental effects on broiler health and could be an efficient probiotic for the broiler colibacillosis prophylaxis.

Effect of Glycodelin on the Cytokine Profile of Rats during Allogeneic Bone Marrow Cell Transplantation.

The protein glycodelin (PP14, PAEP) is associated with pregnancy and exhibits pronounced immunotropic properties. We studied the effect of glycodelin on the cytokine profile of blood serum during transplantation a suspension of allogeneic red bone marrow cells to Wistar rats. Recombinant glycodelin was administered to the animals 4 times (14 µg each time). Against the background of bone marrow cell transplantation, the levels of proinflammatory (IL-1α, IL-1ß, and IL-18) and regulatory (IL-7, IL-12) cytokines and CSF (M-CSF) increased in blood serum, which indicates a systemic inflammatory response to the allograft. Glycodelin administration against the background of bone marrow cell allotransplantation led to a significant decrease in the proinflammatory cytokine IL-17A on day 21 of the experiment; the concentrations of the other cytokines remained unchanged. In general, glycodelin can suppress the level of IL-17A, a marker of graft rejection, which opens perspectives for its further investigation as a potential drug.

[MORPHO-FUNCTIONAL CHANGES OF THYMUS TISSUES IN CHILDREN WITH CONGENITAL HEART DISEASE].

Biopsy specimens of the thymus were studied in children aged under 11 months (n = 77) with congenital heart defects and circulatory hypoxia of varying severity. Histological sections were stained with hematoxylin-eosin and Shubich's method (to demonstrate mast cells). The expression of Ki-67, CD3 and CD34 was assessed by immunohistochemistry. The ultrastructure of thymic tissues was also examined. It was found that the severity of hypoxia determined the morphological changes in the organ associated with a development of large complex of tissue reactions. A disruption of internal structure and a loss of integrity of epithelio-reticular cells and thymocytes were demonstrated in ultrathin sections. Thymocyte proliferation index (Ki-67) and thymocytopoiesis intensity (CD3+) were reduced in all the zones of the thymus. The degree of hypoxia affected the redistribution of CD3+ lymphocytes leading to their accumulation in the medulla. The processes of endogenous regeneration took place which involved the cells of fibroblastic line and progenitor cells (CD34+) together with active formation of new blood vessels. These findings suggest that the morphological changes identified in the tissues of the thymus are a manifestation of tissue adaptation to hypoxia of varying severity under conditions of endogenous regeneration, simultaneously reflecting the processes of substitution cytogenesis.

[Mandibular bone tissue regeneration after the introduction of the implantation system performed on the basis of carbon composite material].

The purpose of this study was to investigate the processes of regeneration of bone tissue after the introduction of new implant systems. In the experiment, performed on 10 male pigs of Landras breed aged 50-55 days and weighing 17-18.5 kg, the time course of histological changes was studied in the area of mandibular regeneration after the formation of tissue defect and the introduction of the implant of a proposed construction. Morphological analysis of the experimental results 90, 180 and 270 days after the operation demonstrated the process of reparative regeneration of damaged bone along implant-bone block boundaries. Bone repair proceeded through the stage of formation of the woven bone with its progressive substitution by the lamellar bone, with the maintenance of the shape, size and symmetry of the damaged organ.

[Morphological and immunohistochemical features of the thymus structure in neonatal infants with congenital heart diseases].

The paper gives the results of morphological and immunohistochemical studies of the thymus in congenital hypoxia induced by the intrauterine development of heart diseases. The morphological changes in the thymic structure have been found to depend on the complicacy of the heart defect determining the degree of hypoxia. There are significant thymic structural changes manifesting themselves as disorders of the epithelial stroma. Its destruction areas exhibit activated fibroblastic differon that positively responds to vimentin and CD34. Increased resistance of lymphocytes to apoptosis has been ascertained and their proliferative properties determined. There is a progressive accumulation of the antiapoptotic protein Bcl-2 in the cytoplasm of thymocytes in the cortex of a thymic lobe and a decrease in Ki-67 expression in the lymphocytes in the thymic lobes, especially in cases of severe heart defects.