Vol 148, No 5 (2015)

The article considers the interaction of pro- and eukaryotes from the standpoint of tissue biology. Examples of long-term persistence of prokaryotes in eukaryotic cells are presented. Morpho-functional characteristics of the interactions of pro- and eukaryotic cells are given, including their ultrastructural relationship. It is shown that the symbiosis between unrelated organisms is a reflection of their adaptation to the use of trophic resources of the environment. One of the implications of endocytobiosis of non-pathogenic bacteria in eukaryotic cells is to increase the biodiversity. The concept of multicellular eukaryotic organisms as complex cell and tissue systems of symbiotic interactions of pro- and eukaryotic cells, is discussed.

Bcl-2 protein expression was studied in hippocampal CA1, CA2, CA3 and CA4 pyramidal neurons in Mongolian gerbils (Meriones unguiculatus) ,, of the in in the early (Day 2) and late (Day 7) reperfusion period after a 7-minute forebrain ischemia and following ischemic postconditioning (IPostC), as well as in sham-operated animals (n=60). In the latter, the highest level of Bcl-2 expression was found in CA4 neurons, while the lowest - in CA1 neurons (P<0.01). Reversible ischemic brain damage led to the increasing deficit of morphologically unchanged hippocampal neurons with the increasing duration of reperfusion period. This was accompanied by a significant decrease in expression of Bcl-2 in the early reperfusion period, but in the late reperfusion period this decrease largely disappeared. IPostC, applied as three episodes of ischemia-reperfusion lasting 15/15 seconds, contributed to significant increase in the number of morphologically unchanged CA1 and CA3 neurons in the early reperfusion period, while the expression of Bcl-2 was increased in morphologically unchanged neurons in all the hippocampal areas. In the late reperfusion period after IPostC, the number of unchanged neurons was increased in hippocampal areas CA1, CA3 and CA4 (P<0.05), while a significant increase in Bcl-2 expression (by 12.7%, P<0.01) was detected only in CA1 neurons. The results suggest that the cytoprotective effect of IPostC in hippocampal CA1 area is realized through a mechanism leading to increased expression of Bcl-2 protein, i.e., by blocking apoptosis.

Ultrastructural changes in synapses between parallel fibers (PF) and the spines of Purkinje cell dendrites (PCD) in frog cerebellum were studied after exposure to high concentrations (1 mM) of glutamate (Glu) and NO-generating compound in experimental model. It was shown that exposure to Glu resulted in the envelopment of the terminal bouton by the spine, while under the influence of NO-generating compound, on the contrary, the spine was surrounded by the bouton. Morphological study has shown that in Glu solution there was the predominance of synapses in which the glial cells surrounded the spines, while in the presence of NO they covered the boutons. After the electrical stimulation of PF, the relative number of synapses, containing the boutons surrounded by glial cells, was 10 times higher as compared to those in which the glial cells surrounded the spines. The observed morphological changes reflect the functional state of synapses between PF and PCD in response to the damaging effects of excess Glu and NO, that is expressed in different forms of synaptic contacts and neuron-glial structures.

The experiments on the elongation of the tibia in 18 dogs were performed for 10 days using the Ilizarov apparatus with an automatic drive providing the pace of 3 mm/day for 120 moves (group 1) and 180 moves (group 2). The impact of fractionation of distraction on the structure of the peroneal nerve was estimated. In group 1, perineurium micro-injuries and endoneural blood vessel destruction were detected. In group 2, perineurium preserved its integrity and fine-lamellar structure, endoneural blood vessels were also preserved, however, the decrease in the total area of nerve fiber bundles was more pronounced. Morphometric analysis of the preserved myelinated nerve fibers 60 days after the cessation of distraction indicated less marked axonal atrophy and better myelination in group 2.

The peculiarities of structural transformations of different portions of the cranial caval veins were studied in 60 rats at Days 1-30 after birth. The alternating periods of rapid and slow increase in the length of the cranial caval veins were identified. Wall thickness in all the parts of the right cranial caval vein increased less significantly as compared with its length during the early period after birth (Days 1-11). At Days 16-30, the rate of growth of the length was reduced, while the vessel wall thickness increased. This regularity was not observed in the development of the left cranial caval vein. Instead, this vessel demonstrated alternating periods of accelerated and decelerated growth of the wall thickness.

The objective of this study was to examine cell proliferation, apoptosis and angiogenesis in pathologically unchanged lung and in non-small cell lung cancer with the use of appropriate markers. The material studied included samples of pathologically unchanged lung (n=80) and those obtained at operations in 237 cases of non-small cell lung cancer. Immunohistochemical methods were used to demonstrate Ki-67, topoisomerase IIα (ТороIIα), p53, bcl-2, bax, CD34 and podoplanin. Argyrophilic proteins associated with nucleolar organizer regions (Ag-NOR proteins), were detected by impregnation with silver nitrate. The quantitative data were obtained and the peculiarities of the expression of markers associated with proliferation, apoptosis and angiogenesis in pathologically unchanged lung were determined. In the alveoli, the labeling index of Ki-67 and ТороIIα was less than 1%, AgNOR area index was equal to 1.31±0.20; p53, bcl-2, bax expression was absent, density of blood vessels was equal to 86 (73-102), while lymphatic vessels were absent. In the bronchus, the labeling index of Ki-67 and ТороIIα were respectively 4 (1-8) and less than 1%, AgNOR area index - 1.85±0.24, bax expression - 100%, density of blood and lymph vessels -22 (17-31) and 4 (2-7) respectively; p53 and bcl-2 expression were absent. The results were compared with the expression of markers in non-small cell lung cancer. This comparison has fundamental and differential diagnostic value in the study of histopathological lung material. The expression of markers associated with proliferation, apoptosis and angiogenesis changes from pathologically unchanged lung to non-small cell lung cancer.

Using general histological and immunohistochemical methods, the sources of «reserve cells» of the epithelial lining of the uterus and vagina were studied on the material obtained from human embryos and fetuses. From 13th to 20th week of fetal development, the epithelial lining of the cervix was formed with the participation of the urogenital sinus (UGS). The cells of the latter interacted with the coelomic epithelial cells of the paramesonephric ducts (PMD). After 25th week, UGS cells were dispersed along the length of the cervix, lying on the basement membrane beneath the columnar epithelial cells. It is suggested that epitheliocytes of UGS are the source of the «reserve cells». Taking into account the tissue nature of the «reserve cell» it is expedient to determine them as mesonephroblasts. Cells are present in the cervical epithelium as a concomitant determined cellular differon.

The study of the sections of Wistar rat pancreas (n=4) using the methods of immunocytochemistry and confocal laser microscopy has demonstrated previously unknown fact of the presence of NeuN protein in the secretory epithelial cells of the exocrine part of this organ. The protein was located in the apical part of the cytoplasm slightly below the zone of zymogen granules. Until now the nuclear protein NeuN was considered to be the panneuronal differentiation marker and was used in the studies of neurogenesis.