Existence of glucocorticoid-specific receptors in the plasma membranes of rat liver

It was found that isolated plasma membranes whose purity was assayed by determinations of marker enzyme activities, specifically bind dexamethasone. The association constant and the number of binding sites were found to be equal to (7,03 +/- 4,05) . 10(9) M-1 and (1,6 +/- 0,18) . 10(-14) mol/mg protein, respectively. It was assumed that lipoprotein components of plasma membranes are involved in this binding.     

Cryopreserved neurons of a mollusc are capable of morphological differentiation in culture in vitro

It was shown in culture in vitro that neurons isolated from the cryopreserved brain of adult molluscs Lymnaea stagnalis L. retain viability. Isolated brains were frozen in liquid nitrogen vapors at a rate of 400-500 degrees C/min in the presence of 2 M dimethylsulfoxide. The samples were then plunged into liquid nitrogen and stored from 1 month to 2 years. Upon thawing and removing the cryoprotectant, the neurons were isolated from the brain and then introduced into a cellular culture in vitro. It was shown that the thawed neurons were capable of regenerating new nerve processes similar to those formed by unfrozen neurons in the control.     

Ontogeny-specific interaction of psychophysiological mechanisms of emotional perception and educational achievement in students

In order to explore the process of adaptation of children to school environment psychophysiological characteristics of perception of emotional speech information and school progress were experimentally studied. Forty-six schoolchildren of three age groups (7-10, 11-13, and 14-17 years old) participated in the study. In experimental session, a test sentence was presented to a subject through headphones with two emotional intonations (joy and anger) and without emotional expression. A subject had to recognize the type of emotion. His/her answers were recorded. School progress was determined by year grades in Russian, foreign language, and mathematics. Analysis of variance and linear regression analysis showed that ontogenetic features of a correlation between psychophysiological mechanisms of emotion recognition and school progress were gender- and subject-dependent. This correlation was stronger in 7-13-year-old children than in senior children. This age boundary was passed by the girls earlier than by the boys.     

Sporogenesis, antibiotic biosynthesis and the systematic position of Fusidium coccineum

Cytomorphological study of the wild and isogenic improved strains of F. coccineum revealed that with increasing of the antibiotic potency the character of the strain sporulation changed towards predominant formation of the spore "heads" which is characteristic of the sporogenesis of the genus Acremonium. These data allow one to revise the systematic position of the strains of F. coccineum and to classify them according to Gamsas belonging to Acremonium designated as Acremonium fusidioides. The criteria of the highly potent strains of this organisms are the following: formation of the spore "heads", changes in the event sequence during sporulation, decreasing of the spore index L/B with an increase in the strain potency. These criteria may be used in further improvement on the organism.     

Ultrastructure of the cells and DNA synthesis in skeletal muscle regeneration. A study of the regeneration of the frog sartorius muscle by an electron microscopic autoradiographic method

The ultrastructure of cells of the regenerating frog's sartorius muscle and their capacity to synthesize DNA was studied by means of 3H-thymidine (3HT) electron microscope autoradiography. On the 8-17th post injury (p.i.) days, 2 hours following 3HT administration, only mononuclear cells were seen labeled, the myotube nuclei incorporating no 3HT. Along with the endothelial cells, fibroblasts, phagocytes and cells identified conventionally as myoblasts, satellite cells examined from both necrotic and viable parts of injured myofibers were labeled. No myoblast sequestration from the injured myofibers occurred. By the 13-15th p.i. days, numerous myoblast-like cells are accumulated beneath the glycocalix layer covering the free ends of myotubes which are rich in ribosomes and display an active sarcomerogenesis. Some of these myoblast-like cells become labeled after 3HT pulse. The 13 day p.i. regenerates examined 72 hours following 3HT injection display labeling in numerous myotube nuclei. This is indicative of the myoblast fusion, which is believed to play a principal role in the regenerative somatic myogenesis. Within the myonuclei adjacent to the areas of the regeneration, membranous and/or fibrillar structures of an unknown origin were frequently observed.