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Byline: T. B. Shvets-Teneta-Gurii (1), G. I. Troshin (1), M. R. Novikova (1), N. M. Khonicheva (1), O. A. Shostak (1), I. V. Borovskaya (1) Keywords: rat; cerebral cortex; sleep-waking cycle; oxidative-reductive state Abstract: Freely mobile mongrel male rats weighing 300--350 g were used for studies of changes in the oxidative-reductive (redox) state of brain tissue during cycles of waking, slow-wave sleep, and paradoxical sleep, by recording the potential of the oxidative-reductive state of brain tissue with platinum electrodes implanted into the cerebral cortex ad hippocampus. Electromyograms were also recorded from the cervical muscles, and overall movement activity was also recorded. A common platinum reference electrode was implanted into the nasal bones. These experiments showed that in rats, episodes of waking and paradoxical sleep occurred on the background of increases in the oxidation-reduction potential state of brain tissue at a series of brain points, which we termed 'metabolically active.' Transitions from waking and paradoxical sleep to slow-wave sleep were accompanied by decreases in the potential of the redox state. The magnitude of changes in the tissue redox state varied up to 100 mV. It is suggested that transitions from waking and paradoxical sleep to slow-wave sleep are accompanied by dynamic changes in the balance of brain tissue energy metabolism between the main energy sources. Oxidative phosphorylation dominates in waking and paradoxical sleep, while aerobic glycolysis dominates slow-wave sleep. We suggest that this latter should be interpreted as a decrease in the potential of the tissue redox state and the formation within the tissue of oscillations during slow-wave sleep. Formation of oscillations is typical for acceleration of glycolytic processes. Recently published data suggest that the major compartment or aerobic glycolysis is the astroglia. Author Affiliation: (1) Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow Article History: Registration Date: 12/10/2004

Byline: T. B. Shvets-Teneta-Gurii (1), I. V. Borovskaya (1), A. G. Dubinin (2), M. R. Novikova (1), G. I. Troshin (3), O. A. Shostak (1) Abstract: Paradoxical sleep is regarded by many authors [1, 2, 6--11] as consisting of episodes of integrative brain activity, this view being based on data relating to changes in overall brain electrical activity (depression of electrocorticograms or the appearance in electrocorticograms of oscillations at the theta rhythm) and increases in neuron activity, data showing negative changes in the potential of the direct current, and data demonstrating increases in brain temperature and local brain blood flow, increases in glucose utilization, and increases in the levels of free oxygen in brain tissue. We have previously observed that episodes of paradoxical sleep are accompanied by increases in the redox potential of brain tissue (E) by several millivolts [3]. In these experiments, we used a direct current amplifier with a low input resistance (1 M[OMEGA]), which decreased the true magnitudes of changes in E accompanying episodes of paradoxical sleep. One of the aims of the present work was to determine more accurate measures of the functional changes of this type of sleep, by using a direct current amplifier with a high input resistance (1 G[OMEGA]). The second aim of the present work was to obtain more accurate data on differences in changes in oxidative metabolism in different parts of the brain during episodes of paradoxical sleep, by making simultaneous recordings of E from two points of the brain, using several different combinations of pairs of points. Author Affiliation: (1) Russian Academy of Sciences, Institute of Higher Nervous Activity and Neurophysiology, 5A Butlerov Street, 117865, Moscow, Russia (2) D. I. Mendeleev Chemical-Technical University, Moscow (3) Science Research Institute of Communications, Moscow Article History: Registration Date: 08/10/2004

Hippocampus is believed to be selectively vulnerable to stress. We hypothesized that this phenomenon may be mediated by relatively high vulnerability to neuroinflammation related to impairments of local glucocorticoid metabolism and signaling. We have evaluated inflammatory responses induced by acute or chronic combined stress in the cerebral cortex and hippocampus as well as circulating and brain corticosterone (CS) levels as well as expression of corticosterone target genes. The hippocampus showed higher stress-induced expression of the proinflammatory cytokine IL-1β as compared to the cerebral cortex. A month after the termination of the chronic stress, IL-1β mRNA in the cerebral cortex reached control level, while in the hippocampus it remained significantly increased. Under chronic stress, the maladaptive inflammatory response in hippocampus was accompanied by a significant increase in local CS levels, as compared to cerebral cortex. Under acute stress, the increased CS level induced changes in CS-regulated genes expression (CRF and IGF1), while this phenomenon was not observed after chronic stress. Thus, the hippocampus appears to be more vulnerable to stress-induced inflammation as compared to the neocortex and demonstrates persistent inflammatory response induced by chronic stress. Stress-induced maladaptive inflammatory response is associated with a selective increase in hippocampal CS accumulation and changes in CS signaling.

The number and viability of microorganism specimens Bacillus spp. isolated from permafrost soil remained unchanged after incubation at temperatures of -16-37°C. Experiments on F1 CBA/Black-6 mice showed that incubation of bacteria at -5°C for 72 h promotes a decrease in their toxicity and an increase in their immunostimulating effect.

Local application of ointment with Bacillus spp. strain MG8 (15,000-20,000 living bacterial cells), isolated from permafrost specimens, on the skin wound of about 60 mm(2) stimulated the reparation processes in experimental mice. A possible mechanism stimulating the regeneration of the damaged tissues under the effect of MG8 could be modulation of the immune system reactivity with more rapid switchover to humoral immunity anti-inflammatory mechanisms aimed at de novo synthesis of protein.

The effects of a new microorganism species (Bacillus spp., strain M3) isolated from permafrost specimens from Central Yakutia (Mamontova Mountain) on the bone marrow hemopoiesis were studied on laboratory mice. Analysis of the count and immunophenotype of bone marrow cells indicated that even in low doses (1000-5000 microbial cells) these microorganisms modulated hemopoiesis and lymphopoiesis activity. The percentage of early hemopoietic precursors (CD117(+)CD34(-)) increased, intensity of lymphocyte precursor proliferation and differentiation (CD25(+)CD44(-)) decreased, and the percentage of lymphocytes released from the bone marrow (CD25(+)CD44(+)) increased on day 21 after injection of the bacteria. These changes in activity of hemopoiesis were associated with changes in the level of regulatory T lymphocytes (reduced expression of TCRαβ) and were most likely compensatory. The possibility of modulating hemopoiesis activity in the bone marrow by low doses of one microorganism strain isolated from the permafrost could be useful for evaluating the effects of other low dose bacteria on the bone marrow hemopoiesis.

Applications of cold and warm activated cellular immunity and orientation and exploratory behavior in mice. Application of cold increased the number of turns to the left in the open field, muscle force, and activity of the food instinct, and caused an increase in the total count of peripheral blood leukocytes. Warm applications reduced the food instinct activity and stimulated the humoral immunity.

Data are presented on chemical study of flavonoid glycosides in some botanical subjects using matrix-assisted laser desorption ionization, compared to HPLC. The method of matrix-assisted laser desorption ionization (MALDI) allows characterizing the composition of anthocyanin and flavonoid mixture without preliminary separation of components with minimal sample preparation, which greatly simplifies identification of bioactive phytogenic compounds.

Qualitative composition and content of anthocyanins in the Rosa spinossima L. fruit were studied. The anthocyanin sum was isolated by talc adsorption with subsequent desorption. The presence of anthocyanins in the resultant fraction was confirmed by thin layer chromatography. Three spots corresponding to anthocyanins were found. Anthocyanins were identified by mass spectrometry. Ion peaks corresponding to glycoside cyanidin and delphinidin were found. Position of sugar in the glycoside structure was determined by UV spectrophotometry with aluminum chloride. The content of anthocyanins was measured by direct UV spectrophotometry by the anthocyanins absorption. Anthocyanin content in raw material in conversion to cyanidin-3-glucoside was 1.46±0.03%.

The immunobiological potential of a new microorganism species isolated from permafrost specimens (PMO strain 3M) collected from the Mammoth Mountain in Yakutia was studied in laboratory mice. PMO injected intraperitoneally in doses of 2500 to 50 × 10(6) microbial bodies caused characteristic dose-dependent effects on the structure and functions of the immune system (thymus and spleen indexes, functional activity of splenic macrophages, cellular and humoral immunity). Doses of PMO stimulating functional activities of both cellular and humoral immunity were detected.

Juniperus oblonga Bieb is widely spread in the Caucasus Mountains, particularly in its eastern and southern regions. Diuretic effect of juniper berries is determined by the presence of volatile oils and polyphenol complex, particularly flavonoids. Flavonoids were extracted from raw material with 70% ethanol and then with ethyl acetate. Column chromatography of ethyl acetate fraction on polyamide yielded 5 compounds, which were identified on the basis of physicochemical constants of parent compounds and products of acid hydrolysis and alkaline degradation of aglycones and on the basis of UV-spectroscopy as apigenin, isoquercitrin, apigenin-7-glucoside, quercetin-3-rutinoside, and scutellarin-7-glucoside. Quantitative composition of flavonoid in equivalent to rutin concentration in Juniperus oblonga Bieb was 0.910±0.007% (UV-spectrophotometry data).

Monarda fistulosa essential oil characterized by pronounced therapeutic effects is proposed for the treatment of seborrhea. Studies of its antibacterial, antimycotic, and antiinflammatory activities showed that it inhibits microorganism growth and is superior to hydrocortisone in combination with vitamin B6 by its antiinflammatory activity.

Granulomatosis was induced in male Wistar rats by intravenous injection of SiO(2). The course of SiO(2) granulomatosis was cyclic in animals receiving radon baths: phase 1 was characterized by an increase in the number and size of granulomas, while during phase 2 the intensity of the inflammatory process decreased and fibrosing of granulomas progressed. No trends to alleviation of the inflammatory process were noted in rats with SiO(2) granulocytosis receiving tap water baths.

The systems responses of the brain to therapeutic transcranial electrical and electromagnetic stimulation were studied and the neurophysiological criteria for assessing the efficacy of this treatment were identified using comparative clinical and experimental studies with analysis of spontaneous bioelectrical activity, along with assessment of behavioral and clinical measures. Study groups consisted of six patients with chronic post-traumatic unconscious states during courses of transcranial electrical stimulation and 17 intact Wistar rats subjected to transcranial electromagnetic stimulation. A relationship was found between the effects of transcranial stimulation and the initial level of intercenter interactions of brain bioelectrical activity assessed in terms of coherence. Hypersynchronization of biopotentials, identified as a major element in the reactivity to this type of stimulation, may be of the greatest value in the recovery of patients with cerebral pathology in cases with initially reduced levels of intercenter interactions in the absence of pathologically increased functional connections in the brain.

Gas chromatographic method for measuring volatile sulfur compounds in solutions for intravenous infusions is proposed.

This article is devoted to an analysis of the factors forming slow changes in the potential of a metallic electrode coming into direct contact with living tissue. Data are presented in this paper according to which, the electrochemical activity of the tissue also participates, in addition to electrical activity, in the formation of the electrode potential. The article is in the nature of a discussion.