The effect of a 105-day experiment in isolated environment on the functional state of the cardiovascular system of the participants

We studied the effect of a 105-day experiment in an isolated environment on the functional state of the cardiovascular system of six male participants aged 25 to 40 years; as well as the diagnostic significance of novel research methods, in particular, the ECG variance mapping and the assessment of endotheliumdependent flow mediated dilation in the right brachial artery. Our results indicate that the conditions of isolation resulted in changes in the internal cardiac hemodynamics and, consequently, to progressive development of cardiac arrhythmias. This is probably related to the changes in neurohumoral regulation of the heart and disturbance of the sympathetic and parasympathetic innervations. The changes in the vascular wall and vasomotor endothelial function in two subjects suggest endothelial dysfunction and an increased risk of atherosclerosis.     

Alkaline phosphatase activity of normal and transformed cultured human cells

A study was made of the relationship between the activity of alkaline phosphatase and the proliferation of cultured human cells with different replicative potentials. It is shown that alkaline phosphatase plays a role as one of endogenic stimulators of cellular proliferation. The ageing of diploid cells is accompanied by a decrease in the enzyme activity. Maximum activity was observed during a period of logarithmic cell growth. Addition of placental alkaline phosphatase to the synchronized diploid cells stimulated DNA synthesis in the S-phase of the cell cycle. Heteroploid cells with a high growth rate possessed a 30-100 times higher alkaline phosphatase activity than in the diploid cells. Under certain conditions alkaline phosphatase may presumably function as a proteinkinase.     

Intracellular mechanisms participating in the formation of neuronal calcium signals

Ion and metabolic processes in the endoplasmic reticulum, mitochondria, plasma membrane, etc. providing calcium signaling in the cells of excitable and nonexcitable tissues are discussed.Neirofiziologiya/Neurophysiology, Vol. 36, Nos. 5/6, pp. 405–417, September–December, 2004.This revised version was published online in April 2005 with a corrected cover date and copyright year.     

Study of the effects of amyotrophic leukospongiosis causative agent on neuroglia cells in vitro

The influence of amyotrophic leukospongiosis (AL) causative agent on the ultrastructure of different types of cells of dissociated rat embryo brain and spinal cord cultures was studied. The AL agent belongs to the unconventional viruses (prions) and causes degenerative changes in the CNS. Large neurons and fibrous astrocytes were shown to be most sensitive. It was noted that the time of development and the degree of the dystrophic changes depend on the agent concentration. The destruction of cell membranes resulted in the pair neuron confluence. The formation of giant mitochondria with intramitochondrial inclusions was detected. It is supposed that the energetic apparatus of sensitive cells is primarily damaged by the infectious agent.     

Trial of different nutrient media for the production of an intracellular thermolabile enterotoxin by Escherichia coli strains H74-114 and 86

The conditions of cultivation, ensuring the maximum accumulation of intracellular thermolabile enterotoxin in the cultures of two E. coli strains of different origin, have been studied. Culture media manufactured in the USSR have been selected and the conditions of cultivation, necessary for obtaining intracellular thermolabile enterotoxin in preparative amounts, have been established. Under these conditions the yield of thermolabile enterotoxin in 1.4 mg per 1 liter of culture medium for strain H74-114 and 1.0 mg per 1 liter of culture medium for strain 86.