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L A Maksimenko

Publications and source records attributed to L A Maksimenko.

12 recordsLinked to original sources
PubMed1991

[The range of control of the afferent system of the flexor reflex].

The control processes caused by the action of electric inhibition of the nerve fibres and depolarized and hyperpolarized influences in the neurones structures of the spinal cord are discussed. Three typical bands of the amplitude control of motor apparatus in the multineuronic reflex ring are distinguished. The transmission of the action potentials in the battle control bands is carried out by the double way modulation. The first band is characterized by the most effective control with amplitude of the signal control in the limit of three thresholds. In the third band the transmission of information is possible in the inversion regime with unsteady polarity of the reflex movement. The second band unfits for the transmission of control commands.

Action Potentials↗
PubMed1987

[Transmission of amplitude-modulated signals in the presynaptic inhibition system of the cat spinal cord].

In experiments with cats under the hexenal anesthesia it has been found that the transmission of information in multineuronic reflex ring carries out by frequency-dependent way. The optimum frequency subrange corresponds to each meaning of the modulation depth. Appearing signal distortions are accompanied by the phase lead of dorsal potentials with maximum on "resonance" frequency. The mechanism of presynaptic inhibition serves as control command amplifier. For all this the information signal amplitude grows, signal relation to noise increases, noise immunity of information transmission through the neuronic communication channel of multineuronic reflex ring improves considerably.

Action Potentials↗
PubMed1985

[Comparative analysis of possible ways of activating depolarizing neurons in the system of flexor reflex afferents].

Two schemes of activation of depolarizing neurons at the level of the first synaptic relay in the polysynaptic reflex arc were compared on an electronic model. It is shown that in the system without a feedback a long delay in the transition process of dorsal surface potentials must be observed during rhythmic stimulation of the afferent input. A decrease in the amplitude-frequency characteristics in this system must be observed as well. These findings contradict to neurophysiological data about changes in the N1-cord dorsum potential. The conclusion is made that a more acceptable scheme of activation of depolarizing neurons is the one with a negative feedback circuit formed by C-interneurons.

Animals↗
PubMedDate not supplied

[Enzyme activity of nucleocapsid proteins of the curly potato dwarf virus].

The individual nucleocapsid proteins of phytorhabdovirus of curly potato dwarf were isolated: N-protein (m. w. 56 kDa), NS-protein (m. w. 49 kDa), L-protein (m. w. 128 kDa). It was establish that L and NS proteins displayed enzyme activity in the replication, phosphorylation and adenylation systems in vitro. Major N protein (m. w. 56 kDa) did not show the enzyme activity in these systems. The revelation of RNA-polymerase, poly(A)-polymerase and proteinkinase activities of nucleocapsid proteins are characteristic of the viruses belonging to the Rhabdoviridae family.

DNA-Directed RNA Polymerases↗
PubMedDate not supplied

[Physico-chemical properties and functional peculiarities of mRNP of different subcellular location of Nicotiana rustica plants affected by potato curly dwarf virus].

mRNP of different subcellular location of N. rustica plants affected by PCDV contain virus-specific proteins. RNA-replicase, poly (A)-polymerase and protein kinase have been found in mRNP under study. The most expressed replicase, poly(A)-polymerase and protein kinase activity has been noticed in the systems containing membrane-bound non-polysomal mRNP.

Cell Membrane↗
PubMedDate not supplied

[Functional properties of prosomal protein 39 kappaDa from Datura stramonium leaves infected with Potato Virus X].

Free cytoplasmic informosomes isolated from Datura stramonium plants infected by PVX contain a low-molecular ribonucleoprotein complex (RNP). This complex as to its main physico-chemical parameters (sedimentation coefficient 10S, buoyant density in CsSO4 1.31 g/cm3, stability to 1% lauroylsarcosinate-Na) corresponds to the prosome (inhibitory RNP). Prosomes isolated from free mRNP of D. stramonium plants infected by PVX contain the protein of 39 kDa. This protein was shown to be capable to phosphorylate in vitro in the composition of informosomes and prosomes. It is possible that this protein can be the protein-repressor, since it is absent in the translated polysome-associated form of mRNP. The label incorporation has shown that the protein of 39 kDa is able to reduce in vitro the template activity of genomic RNA PVX to 40% and RNA TMIV--to 30%. Moreover, the protein 39 of kDa has the protease activity. It affects substrate-case in like trypsin. It is supposed that it can participate in splitting the intracellular proteins as well as in the expression of the virus genome, it can also influence the template activity of cell RNAs.

Datura stramonium↗
PubMedDate not supplied

[The coding of frequency-modulated signals by the presynaptic control system].

Mechanism of presynaptic inhibition transforms frequency-modulated sensory signals amplitude-frequency-modulated reaction of potentials of dorsal side of spinal cord. Frequency regulation is characterized by a wide threshold range which is several times higher than amplitude regulation mode. Neuromuscular system of motor apparatus is a kind of impulse-frequency detector. The system isolates analogous amplitude changes of mechanic movements by demodulation of frequency-modulated dorsal potentials. The detection mode is facilitated by preliminary transformation.

Animals↗