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A V Tereshchenko

Publications and source records attributed to A V Tereshchenko.

At least 19 recordsLinked to original sources
PubMed1991

[Electrophysiological analysis of corticofugal influences on neurons of the preoptic area].

Evoked potentials (EPs) and neuronal responses of the medial (MPO) and lateral (LPO) preoptic region (RPO) and adjacent areas of the hypothalamus to stimulation of the prefrontal (area 8), cingulum (area 24), periamigdaloideus (RPA) cortex and hippocampus (area CA3) have been studied on cats anesthetized with ketamine. Cortical areas were selected according to their evolutionary status. It is determined that the most pronounced EPs are generated in the RPO to stimulation of the periamigdaloideus and cingulum cortex. A close correlation between responses of single units and EPs waveforms is shown. The majority of neurons responsible for cortical stimuli are located mainly in the basal part of the LPO. It is this area of the RPO where the prevalence of initial excitatory reactions is observed. The MPO contains much less neurons responding to cortical stimulation. In this area of the RPO mainly initial inhibitory reactions are registered. For the LPO a ratio between the inhibitory and excitatory reactions is 0.6:1, for the MPO the same ratio is 5.8:1. In the area of the RPO adjoining the bed nucleus stria terminalis (BST) the initial inhibitory reactions prevail over the initial excitatory ones too (ratio 4.9:1). In the area of the RPO immediately adjoining the nucleus supraopticus the initial excitatory reactions are registered and the ratio between the initial inhibitory reactions and initial excitatory ones is 0.7:1. In the RPO a pronounced convergence of the stimuli from the different cortical areas to the definite cells is found as well. In the RPO which is a zone of wide convergence 3/4 of neurons responded to stimulation of two and more cortical inputs. The combinations of inputs from the prefrontal and cingulum cortex as well as from prefrontal and periamigdaloideus cortex are the most frequent types of convergence of different cortical stimuli to the preoptic neurons.

Animals↗
PubMed1991

[Reactions of neurons of the preoptic area in the presence of serial cortical stimuli].

Evoked potentials (EPs) and neuronal responses of the medial (MPO) and lateral (LPO) preoptic region (RPO) and adjacent areas of the anterior hypothalamus to serial (6-300 s) stimulation of the prefrontal (area 8), cingulum (area 24), periamygdaloideus (RPA) cortex and hippocampus (field CA3) were studied on experimental cats anesthetized by ketamine. Cortical areas were selected according to their evolutionary status. Responses of preoptic neurons to serial stimulation were grouped into four main types: excitatory, inhibitory, excitatory on-off-effect and inhibitory on-off-effect. No pronounced changes in the patterns of response reactions were found when frequency of the stimuli increased, only intensity of the reactions changed. Neurons responding to serial cortical stimulation were located mainly in the central part of the MPO and in the basal part of the LPO. These areas of the RPO contained neurons with the most pronounced convergence of different cortical stimuli to the same cell. In serial cortical stimulation inhibitory reactions developed more frequently than excitatory ones (ratio 3.4:1). A gradient of inhibitory reactions to stimulation of different cortical areas was observed while comparing them in terms of evolution from new to old structures. Prevalence of inhibitory responses over excitatory ones was minimal (ratio 1.7:1), when the neocortex (area 8) was stimulated and it was more pronounced (ratio 1.9:1) during stimulation of the evolutionary intermediate cortex (area 24). That prevalence was still more significant (ratio 4.5:1) in case of paleocortical (RPA) stimulation and it was the most pronounced (ratio 10.2:1) during stimulation of the archicortex (hippocampus).

Animals↗
PubMed1988

[Characteristics of morphogenesis of cryptorchism in childhood].

The main morphological features of undescended testes in children of 2-14 years old were incomplete cytodifferentiation of Sertoli cells (absence of transition of Sa = Sb cells into Sc type), reduced number of spermatogonia and dystrophic changes in germ cells. Intense progressive sclerosis developed in the interstitium and walls of seminiferous tubules. The dark Sertoli cells were described as a distinct cell type for the first time. The results of the morphological study indicated that cryptorchism should be surgically corrected during the first two years of life.

Adolescent↗
PubMed1985

[Testicular torsion in children].

The observations of 40 children with testicle torsion have shown results of the surgical treatment to depend not only on duration of the postoperative period but also on the degree of torsion and anatomical peculiarities of the spermatic cord. The preserved during operation testicle where non-recognized irreversible lesions have already occurred due to torsion can in later period result in the appearance of antisperm antibodies and threat of a lesion of the contralateral testicle.

Adolescent↗