Ultrastructural dynamics of the muscular branches of the normal brachial plexus and in exposure to reflexotherapy

The changes in the ultrastructure of myelinic fibers of branchial plexus muscular branches have been studied during exposure to acupuncture of different duration. The studies were performed using muscular branches obtained from the forelegs of sexually mature white rats, weighing 150-170 g. The nerves were processed for electron microscopy according to a conventional technique. It is demonstrated that myelinic conductors react to the exposure by a complex of structural changes of a reactive, non-specific nature.     

Neuronal Networks on Multielectrode Arrays as High Sensitive Biosensors of the Functional State of Nerve Cells

The dynamics of changes of spontaneous neuronal activity in primary hippocampal cell cultures developing on a multielectrode array (MEA) was studied using a multielectrode system. The intensification of bioelectrical activity, which depended on the duration of cultivation and stabilized by the second week in vitro, has been revealed. An increase in the concentration of glutamate (up to 2 μM) by addition into the incubation medium during the stabilization period resulted in a rapid and significant reorganization of the neuronal network activity pattern. On the other hand, inhibition and subsequent gradual recovery of the neuronal network activity immediately after the neurotransmitter addition at higher concentrations (50 or 100 μM) have been observed. At the same time, on some electrodes in the presence of high doses of glutamate (100 μM), a complete or partially irreversible suppression of the activity has been recorded. A significant reduction in spontaneous activity of the neuronal network, which was not accompanied by neuronal death, also occurred when copper ions (Cu²⁺) at a concentration of 10 μM were added into the incubation medium for 48 h. The obtained data demonstrate high biosensor sensitivity of the neuronal network cultured on the multielectrode array, which makes it possible to use it as an effective test system for studies of biologically active compounds.     

Appearance of entodermal antigen in the mouth mucosa of dogs in recurrent spontaneous stomatitis]

An additional component absent in the same areas of the mouth under normal conditions appeared in dogs with spontaneous stomatitis in the ectodermal derivatives (mucosa of the cheeks, tongue and the hard palate). This component proved to be fully identical to the antigens of the mucosa of the soft palate, esophagus, stomach, small and large intestine, which were entodermal derivatives. No entodermal antigen was revealed in the other organs and tissues under study.     

Relationship between hypercapnic and hypoxic stimuli of respiration during muscular activity]

Pulmonary ventilation (V) and alveolar gas composition (PACO2, PAO2) were studied in 12 healthy men who performed gradual muscular work under conditions of controlled hypercapnia, hypoxia, hyperoxia or their combinations. The respiratory response was estimated by absolute values of ventilation at the given PACO2 value and by its rise by 1 mm Hg of increased PACO2 (delta V/delta PACO2) under rest and under transitional and steady-state exercise. The exercise on-switch was accompanied by displacement to the top and an increased slope of the response curve (delta V/delta PACO2) not related to the work load. These changes suggest multiplicative interaction of the neurogenic and hypercapnic drives in the load switch-on. During steady-state exercise an important role of the hypoxic drive was revealed: hypoxemia induced a shift of the delta V/delta PACO2 response curve to a higher level, especially with the great work load. Thus the positive interaction between the hypercapnic and hypoxic respiratory drive augments with muscular exercise.     

Ambiguity of the solution of the inverse problem of electroencephalography

It has been shown for homogeneous conducting medium that if different stationary distributions of current sources form identical potential fields on the plane boundary, the difference between these two distributions is the distribution of current sources with all multiple moments equaling zero. Examples of current source distributions are presented which satisfy this condition.     

Sources of electrophysiological and foci of hemodynamic brain activity most relevant for controlling a hybrid brain–Computer interface based on classification of EEG patterns and near-infrared spectrography signals during motor imagery

A method is described for joint use of electroencephalography and near-infrared spectrography to locate sources of electrophysiological and foci of hemodynamic brain activity during motor execution and imagination. The sources of electrophysiological and foci of hemodynamic brain activity most relevant for controlling a hybrid brain-computer interface based on motor imagery are revealed and discussed.     

Summer bird population in the central part of the Prilenskoe plateau

Bird censuses were taken by routing in the central part of the Prilenskoe plateau, a region poorly explored by ornithologists. The summer population of birds in different habitats at watersheds, in valleys and along riverbanks has been characterized on the basis of the original data obtained.