Dynamics of functional interconnections between cerebral motor cortex neurons of cats under stimulation

In acute experiments on cats the activity of the motor cortex neurons was recorded. The dynamics of interneuronal connections at passive bending and electrostimulation of the limb contralateral to the place of recording was studied by methods of cross-correlation analysis of impulse trains. At passive bending a considerable decrease of the number of common inputs between neighbouring neurons (within 50-100 microns) and an increase in their number between remote (from 100 till 400 microns) cortical neurons. During electro-stimulation a certain increase in the number of direct inhibitory interactions between the neighbouring neurons was observed.     

Comparative Analysis of the Frequency of Neuron Spike Activity in the Sensorimotor Cortex of the Right and Left Hemispheres in Conditions of Immobilization Catatonia in Rabbits

Multineuron activity was recorded from the sensorimotor cortex of the right and left hemispheres during immobilization catatonia in rabbits. The first session of immobilization of the animals was followed by changes in spike frequency in 47% of neurons in the sensorimotor cortex of the right hemisphere. Of these, 30% showed decreases in spike frequency and 17% showed increases. Spike frequency in the sensorimotor cortex of the left hemisphere changed in only 18% of cells, of which 13% showed decreases in spike frequency and 5% showed increases. The spike frequency of neighboring (recorded with the same electrode) neurons could change reciprocally. Differences in neuron activity in the two hemispheres were virtually absent after the second session of immobilization (several days after the first) – spike activity changed in 21% of neurons in the right hemisphere and 24% in the left hemisphere. The ratios of the numbers of neurons with increases and decreases in spike activity in hypnosis also became identical in the cortex of the right and left hemispheres. A hypothesis is proposed for the involvement of cortical neurons in the organization of hypnosis-like states.     

A method of analyzing of the “Dose-effect” dependence in multifactor medico-biological experiments

A conceptual-logical and mathematical approximation model has been created for the organism's response to external factors. The mathematical model of the “dose-effect” dependence for the combined effect of several factors is constructed using the basic equation of the Volterra mathematical theory of the struggle for existence. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 3, pp. 328–331, March, 1994 Presented by L. A. Tiunov, Member of the Russian Academy of Medical Sciences     

Antitumor action of glycopeptides from the cell wall of Lactobacillus bulgaricus

The antitumor action of the substance blastolysin, the main components of which are glycopeptide fragments from the cell wall ofLactobacillus bulgaricus, was studied. Blastolysin exhibits a specific antitumor effect against sarcoma S-180, leukemia P-388, plasmacytoma MOPC-315, adenocarcinoma AKATOL, melanosarcoma B-16, carcinoma LLC, and spontaneous tumors of mice. It has low toxicity, does not depress hematopoiesis, and in the character of its action on tumor tissue it differs essentially from known chemotherapeutic preparations.M. M. Shemyakin Institute of Bioorganic Chemistry, Academy of Sciences of the USSR, Moscow. Scientific-Production Laboratory of Biologically Active Substances, Sofia, Bulgaria. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 12, pp. 709–712, December, 1977.