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Low-frequency vibration, irrespective of its duration (20 Hz, A = 0.4 mm), is shown to increase GABA level, glutamatedecarboxylase enzyme activity (EC 4.1.1.15) in the large hemispheres, cerebellum, brain stem of adult male rats (12 months). Meanwhile GABA aminotransferase activity (EC 2.6.1.19) remains, mainly, unchanged. The observed shifts are more clear under 30 min vibration than under 7h and 30 day effects. Glutaminic and aspartic acids content increases under 30 min and decreases under 7h and 30 day vibration in the given brain structures.

An experimental alcohol intoxication was accompanied by an increase in content of total phospholipids and phosphatide acid in rat brain with simultaneous decrease in content of free ethanolamine. The phenomenon demonstrate the activation of phosphatidogenesis. In the liver tissue an opposite alterations were observed; the lipolytic reactions were activated.

Concentration of L-cystathionine was distinctly increased in rabbit brain within the period of maximal action of drugs, stimulating the central nervous system (phenamine, strychnine corasole). A distinct decrease in content of L-cystathionine was observed within one hour after the administration of strychnine and corasole.

Evaluation of brain metabolism is an important part in examination of brain lesions. Phosphorus magnetic resonance spectroscopy opens up great opportunities for studying the energy metabolism and allows noninvasive examination of metabolic processes occurring both in healthy and in pathologic brain tissue by obtaining a spectrum of phosphorus-containing metabolites involved in the turnover of cell membrane phospholipids. The technique presented in this paper was used to conduct 31 P MR spectroscopy and to estimate the ratio between the peaks of the main metabolites and intracellular pH of the healthy brain tissue of 23 volunteers in the age group under 30 years old in clinical settings. Based on the recorded stable phosphorus spectra of metabolites of the healthy brain tissue, the value of intracellular pH (6.963±0.044) and the ratio of the main PME/PDE peaks (1.17±0.20) were calculated. The database was created to subsequently analyze the metabolic changes in brain tissue spectra in norm and in pathology, as well as the intracellular pH variations that have diagnostic and prognostic value.

The possibility of segmenting three-dimensional objects by DICOM-series is well known and available both on specialized workstations and on personal computers. The technique, however, is relatively rarely used in clinical practice, and we believe that the benefits of preoperative preparation using segmented 3D models are underestimated. The article is devoted to our experience in using segmentation of anatomical structures based on CT and MRI for preoperative preparation for surgical operations performed in neurosurgical departments on patients with vascular pathology. The paper discusses the types and possibilities of segmentation, provides some examples describing the clinical use of the technique.

This paper presents findings of the comparative computer analysis of brain bioelectrical activity (EEG) in three groups of rural population, which include: long-livers, their close relatives, and representatives of families without records of longevity (the latter was conventionally accepted as the «control group»). Registration of EEG was carried out in conditions of quiet wakefulness with eyes closed. For each group, the average spectral power, frequency characteristics, EEG indices in the ranges of δ-, θ-, α- and β-rhythms were estimated. The results have revealed the increased ascending effects of the synchronizing link and the weakening of the activating assumptions of non-specific brain systems in long-livers, which we consider as reflection of inhibitory mechanisms which are required to replenish the mobilization resources. With regard to the group of relatives, there were revealed a smaller percentage of δ-rhythm and a greater severity of the α-rhythm index in the temporal areas, as compared to the control group, which is indicative of a more optimal level of processes responsible for memory, integration of afferent (auditory and visual) information and harmonization of the emotional background.

The paper describes symptoms, pathogenesis and variants of topographic disorientation. The restorative and compensatory rehabilitation strategies in topographical disorientation are reviewed. It has been concluded that clarification of the variant of topographic disorientation and selection of optimal neurorehabilitation strategies is of great importance for improving medical and social outcomes in patients with stroke and other focal brain lesions.

The paper describes clinical cases in 2 patients (brothers) with giant cell arteritis. It analyzes the genetic and epigenetic aspects of the disease. The data available in the Russian and foreign literature are given.

Chronic cerebral circulatory insufficiency (CCCI) is a result of cerebral microangiopathy, most commonly due to uncontrolled hypertension. In this case, the brain is affected due to recurrent silent infarcts and/or microbleedings without clinical manifestations of stroke and chronic brain ischemia. Progressive cognitive impairments with a preponderance of inadequate attention and lower rates of cognitive performance, with impaired planning and control abilities in relative preservation of memory serve as the main manifestation of chronic progressive non-stroke vascular lesion in the brain. The above impairments are generally associated with emotional changes as affective lability and depression. The paper gives an account of a characteristic clinical case of CCCI, analyzes the mechanisms for the development of neurological symptoms, and sets forth current approaches to managing these patients.

The problem is considered whether the brain response is completely determined by the stimulus and the personal experience or in some cases the brain is free to choose its behavioral response to achieve the desired goal. The attempt is made to approach to this important philosophical problem basing on modern knowledge about the brain. The paper consists of four parts. In the first part the theoretical views about the free choice problem solving are considered, including views about the freedom of choice as a useful illusion, the hypothesis on appliance of quantum mechanics laws to the brain functioning and the theory of mentalism. In other tree parts consequently the more complicated brain functions such as choice reaction, thinking and creation are analyzed. The general conclusion is that the possibility of quite unpredictable, but sometimes very effective decisions increases when the brain functions are more and more complicated. This fact can be explained with two factors: increasing stochasticity of the brain processes and the role of top-down determinations from mental to neural levels, according to the theory of mentalism.

Considerable modifications of the pools of free amino acid and some other compounds in the body ectothermic animals in response to the decrease in temperature are a consequence of the complexity of their adaptation mechanisms. There is no data in the literature on the contribution of such free connections in the low-temperature adaptation of brain ectothermic animals. In a previous study, it was found that as a result of exposure to acute cold shock in the brain eurothermal fish in large numbers appear two ninhydrinpositive compounds of unknown nature. In this paper, found that by the beginning of the winter period in the brain are accumulated the same connection also. Found that these are metabolites of phospholipids, phosphoethanolamine and phosphoserine. Phosphoethanolamine pool 94 times more in winter than in summer, and phosphoserine is only in the winter. Assumes that the accumulation of phosphoethanolamine and phosphoserine related to adaptation and modification of membrane phospholipid at low temperatures.

Results of experimental researches of the cerebral blood flow (CBF) dynamics in human under acute hypoxia have been analyzed in the paper. It was found that changes of CBF under severe acute hypoxia are of nonlinear character and have several phases--the primary growth in the first minutes of hypoxia, relative stabilization and secondary growth. Secondary growth has no relation to changes of the hypoxemia level. It begins earlier under more severe hypoxia and in individuals with less resistance to oxygen deficit. Opposite to this, hypoxic training prolongs the time from the onset of hypoxia till the moment of the CBF secondary growth. The hypothesis was suggested that the CBF secondary growth reflects a phase of certain exhaustion of the brain's neuronal mitochondrial reserve capacity, which is accompanied by accumulation of vasoactive substances--precursors of ATP.

The paper gives data on the ways of identifying the pattern of head insertion, wire point, the degree of head flexion and extension, asynclitism, and configuration from the fetal and neonatal skull. The findings are important for the assessment of the course of labor and the quality of its management and for the diagnosis of birth injury. Emphasis is laid on the significance of brain compression in the genesis of fetal asphyxia.

In this paper we present results of a comprehensive analysis of the effect of heat shock at different stages of ontogenesis (adult stage, development of the mushroom bodies and the central complex) on courtship behavior (latency, duration and efficacy of courtship), sound production (pulse interval, dispersion of interpulse interval, the percentage of distorted pulses, the mean duration of the pulse parcels), learning and memory formation compared with the content of isoforms LIMK1 in Drosophila melanogaster male with altered structure of the limk1 gene. The heat shock is shown to affect the behavior parameters and LIMK1 content in analyzed strains of Drosophila. The most pronounced effect of the heat shock was observed at the stage of development of the central complex (CC). Heat shock at CC and adult restores the ability of learning and memory formation in the mutant strain agn(ts3), which normally is not able to learn and form memory. Correlations between changes of content of isoforms LIMK1 and behavioral parameters due to heat shock have not been established.

Mathematical model presented in this paper is based on the data obtained in experimental studies of the mechanism of glutamate-induced deregulation of Ca2+ homeostasis and mitochondrial depolarization in cultured nerve cells. According to our hypothesis the secondary Ca2+ increase during a prolonged glutamate challenge is mainly due to a profound mitochondrial depolarization which stops mitochondrial Ca2+ uptake in the face of continuous Ca2+ influx into the cell. It is supposed that a progressive decrease in mitochondrial NADH during glutamate exposure greatly enhances sensitivity of mitochondria to intracellular Ca-neurotoxicity. A system of equations developed in this work made it possible to provide a satisfactory simulation of most of experimental events observed in the present study.

The results of recent publications on a role of stem cells in the processes of neurogenesis, adaptation and neuroplasticity are summarized. An aim of the paper was to present evidence for a possibility of development and regeneration of cellular elements in the adult brain in normality and pathology. The latter was driven by the discussion of the studies on Alzheimer's disease, Parkinson's disease, schizophrenia and affective disorders. Pharmacological effects on the neurogenesis and perspectives of this research are reviewed.

This paper focuses on the modeling of the neural representations of subjective auditory image motion characters that can be induced by bilateral brain dysfunctions. The modeling is based on a biologically inspired computational model that simulates the behavior of bilaterally located populations of binaural auditory neurons. To assess neural model responses in terms of psychophysical data, a special method is designed. The application of the method reveals the inertness of auditory image motion perception. The results of the modeling show stable influence of both value and bilateral location of the noises (which mimic effect of different brain part dysfunctions) on phenomena of auditory image localization.

Disbalance of the trace elements increases the risk of cerebrovascular disease and, first of all, of ischemic stroke (IS). This is due to the fact that certain trace elements are necessary for maintaining various aspects of the metabolism of neurons and glia. Energetic and plastic processes in the nervous tissue have an extremely active dynamics and their dependence on the availability of brain macro-and micronutrients makes it necessary to take into account the trace element status of patients with IS. This paper presents the results of clinical and basic research which revealed the association between the content of certain trace elements in different biological substrates and the course of stroke. The importance of magnesium, zinc, manganese, copper and selenium for the support of the function of the nervous tissue was shown. The study of the trace element profile in various regions of the brain in patients with IS is a very promising area of modern neurological research.

For many years the modern methods of functional tomographic brain imaging (fMRI and PET) were actively used not only for the research of basic brain functions, but also in clinical practice. In present paper we described the basic characteristics of the signal registered with fMRI and PET, the principles of image reconstruction, as well as the methodological requirements, which are necessary to obtain reliable results. The advantages and limitations of modem tomographic methods of the brain functions investigation are discussed. The need of the complex approach use in brain study is emphasized and methods for the study of functional integration of the brain are suggested.

In this paper possible mechanism of improvement of the functional state of the brain areas, maintaining movement, visual, auditory, and higher functions of the brain during correction of generalized spastic syndrome (botulinotherapy with Xeomin) in patients in a vegetative state (VS) is discussed. If to consider the vegetative state as stable pathological condition (SPC) of the brain, then from the perspective of the theory of structural and functional organization of the brain with systems with rigid and flexible elements (N.P. Behtereva), the therapy led to an unbalance of SPC, "functional release" of neurons and redistribution of their functions to provide other activities, the formation of new interneuronal connections. Taking into account the functional variability of neurons (S.V. Medvedev), blocking neuromuscular transmission in spastic muscles leads to a reduction of abnormal afferent and efferent hyperactivity of motor and sensory neuronal circuits, which releases the brain for other activities. This allows to consider botulinotherapy of pharmacoresistant muscle spasticity in patients in VS and minimal consciousness, not only as a symptomatic treatment, but also as a "indirect neuroprotection".

This paper proposes Bayesian approach to classification of EEG patterns on the basis of imaginary movements of extremities based on analysis ofcovariance matrices of native EEG recordings. An efficacy of a Brain-Computer Interface (BCI) based on the proposed classifier is evaluated. Bayesian classifier is shown to be competitive with the MCSP (Multiclass Common Spatial Patterns) classifier known from the literature as one of the efficient variant for BCI implementation. The influence of eye movement and blinking artifacts on the BCI performance is investigated. It is shown that the presence of such artifacts does not affect the classification accuracy.

The paper is based upon the results of clinic-pathological and virological correlations in 29 lethal cases of influenza in Saint-Petersburg and Leningrad region during the epidemics 2009/2010. Immunohistochemical analysis of lungs, heart and brain using monoclonal sera to HA and HP proteins of influenza virus, virological and morphological analysis of experimental influenza in mice infected by A/WSN/33 (HIN1) and A/California/07/09 (H1N1) viruses had been carried out. In the majority of investigated strains was proved the amino acid mutation with replacement D222G. The replication of virus was demonstrated at the late stages of diseases, but the desquamation of respiratory epithelium and cytoproliferative weren't found out. Besides the "influenza cells", previously described by A. V Zinserling the cells with enlarge light nuclei were observed. Patients with influenza died from respiratory distress syndrome with minimal bacterial infection. We've established that H1N1 virus not only damages the cells of respiratory epithelium and alveolar macrophages but it can injure endothelium of different organs and neuroglia. The questions which have to be discussed are listed.

In the current paper a role of the serotinergic system in organization of impulsive behaviour in animals was considered. The results of influence of antagonists and agonists of the different types and subtypes of 5-HT receptors (1A, B; 2A, B, C; 7) and the effects of the dorsal raphe nuclei lesions on characteristics of impulsivity related with a motor control, mechanisms of attention, reinforcement and decision making were summarized. The data on knock-out animals and the experiments with microdialysis have been also considered. There was emphasized the important role of interaction of 5-HT-, dopamine- and glutamatergic systems in mediation of impulsive behaviour.

Familial (hereditary) cerebral cavernous malformations (CCM) are rare disorders, they have autosomal-dominant type of inheritance. We report 12 families of non-Hispanic descent in which 54 typical CCM were discovered. In 8 families CCM were identified in 2 generations, in 2 - in 3 generations. 46 lesions were supratentorial, 8 - subtentorial. Multiple lesions were present in 67% of cases. Manifestation was observed in 24 persons, including seizures in 17 and hemorrhage in 7. In 9 of 10 families onset of symptoms was earlier with every next generation. In one patient asymptomatic parietal CCM was associated with symptomatic posterior fossa AVM and cutaneous angioma. On the follow-up MRI revealed no new lesions. Surgical treatment was performed in 14 cases: in 13 patients 15 CCM were removed, and 1 patient underwent third ventriculostomy. The paper discusses evaluation and management of families with symptomatic and asymptomatic types of disease, trends and perspectives of further investigations.

The paper describes a critical approach to the existing clinical classifications of central nerve system (CNS) lesion, which do not consider a morphological substrate. It proposes the clinical and morphological directionality of the major classifications of brain lesions: intraventricular, leptomeningeal, and cerebellar hemorrhages and periventricular leukomalacia. The differential diagnosis of periventricular leukomalacia with teleencephalic gliosis, edematous hemorrhagic leukoencephalopathy and other brain lesions. This is a discordance between the clinical, neurosonographic, and morphological classifications of perinatal CNS lesions. The author proposes to elaborate the clinical, morphological, and functional criteria for the differential diagnosis of brain lesions in children, by taking their pathomorphology as a basis.

The paper describes an unusual clinical case. During a neurosurgical operation (removal of parastem tumor (neuroma) on the right side), bilateral registration of the bispectal index (BSI) in order to monitor a hypnotic component of anesthesia showed that the tumor removal stage was marked by a paradoxical reaction of the BSI as an increase in its values up to 70-80% (corresponds to the patient's emergence) on the right, ipsilaterally, with the preserved low BSI values on the left--30-40%. Possible explanations of the observed are considered.

The paper gives the studying the brain in 57 male patients with different types of ethanol intoxication and in 14 control group subjects. The material has been examined by a complex of histological, histochemical, and morphometric studies. The different regions of the brains from those who have died and had signs of alcoholic intoxication exhibit large microorganisms that belong to protozoa, as judged from their structure are identified. They are most commonly oval in shape. The peripheral portions of the parasites' bodies are light and homogeneous and the middle ones are muddy and granular. Their cytoplasm frequently displays vacuoles and inclusions that most often looked like basophilic acicular crystals. One or two nuclei that have large hyperchromic nucleoli are located in the center of the described microorganisms or eccentrically. They are encapsulated in a number of cases. The signs of mitotic division can be seen in individual parasites. Some of them die and are prone to petrification. All these signs allow the described protozoa to be assigned to amoebas.

The paper analyzes the impact of the volemic status and its correction on systemic hemodynamic parameters (transpulmonary thermodilution PiCCO plus technique), the value of intracranial pressure and the biochemical composition of brain interstitial fluid (tissue microdialysis) in the affected and conditionally intact hemisphere in 8 patients with intracranial hemorrhages and a reduced awakening level up to 4-8 scores by the Glasgow coma scale. It has been shown that in patients with significant metabolic disturbance in the involved hemisphere, hypovolemia correction using hydroxyethyl starch 130/0.4 is accompanied by activated oxidative phosphorylation and a lower lactate/pyruvate ratio, without changing the of blood pressure and increasing pulmonary extravascular water.

The paper analyzes the impact of anemia correction on the time course of changes in oxygen tension in the brain and on the biochemical composition of brain interstitial fluid (tissue microdialysis) in the affected and conditionally intact hemisphere in 8 patients with intracranial hemorrhages and a reduced awakening level up to 4-8 scores by the Glasgow coma scale. Anemia correction in patients with intracranial hemorrhage was shown to fail to change oxygen tension in the brain and to be followed by a reduction in lactate/pyruvate ratio in the involved cerebral hemisphere. Only in significant anemia (Hb < 7 g/dl), hemotransfusion elevated cerebral perfusion pressure, by increasing mean blood pressure.

The paper contains the protocol of examination and surgical management of patients with stenosing lesions of mail cerebral arteries. Diagnostic algorithm including evaluation of clinical and instrumental data is presented. Indications for ultrasonic (duplex scanning, transcranial Doppler study) and neuroradiological (CT, spiral CT angiography, MRI) methods of assessment of stenosing lesions are described. Indications for digital subtraction angiography as well as CT- and MR-angiographic studies in postoperative period are to be specified. Variants of reconstructive surgical procedures on carotid, vertebral and subclavial arteries, surgical revascularization of the brain and endovascular procedures on brachiocephalic arteries are discussed. Indications and contraindication to different kinds of surgical treatment and selection of anesthesia are listed. Methods of intraoperative multimodal and neurodynamic monitoring and criteria of application of temporary intraluminal shunt on the main stage of carotid reconstructions are described. Tactics of step-by-step surgical management of multiple stenosing lesions of brachiocephalic arteries is presented. The paper also contains recommendations for preoperative preparation and early and delayed postoperative management of patients.

The paper deals with a comparative study of various aspects of reactivity (substrate and inhibitor specificity, sensitivity to action of hydrophobic organophosphorus inhibitors, capability for reactivation) of preparations of the brain, erythrocyte, and serum cholinesterases of a group of mammals (human, rabbit, rat, cattle, dog, and cat). It has turned out that at preservation of the species and tissue specificity, catalytic properties of cerebral and erythrocytic cholinesterases of the same animal species are very close to each other.

Estimation of the volume of cerebral lesion, reversibility of ischemia and prognosis of the disease determinate management tactics in patients with severe head injuries and non-traumatic intracranial hemorrhages. Data of multimodal neuromonitoring in patients with intracranial hemorrhage in the earlier stages of comatose period were analyzed in this paper. They included incracranial pressure, cerebral perfusion pressure, bulb oxymetry, brain oxygen tension, tissue microdialysis. Typical parameters for different types of neurological outcomes were defined.

The analysis of neurophysiological and neurotransmitter implementing of nervous processing: excitation, inhibition and disinhibition that were distinguished by Pavlov's school was fulfilled in the paper. The systematization of our data and one of literature permits to do the next conslucision. (I) The increasing of inhibitory hyperpolarization processes that become apparent in increasing of slow potential oscillations (SPO) and phasic neuronal activity (alternation of activation and inhibition of action potentials) determines the elaboration of internal inhibition. The basic neurotransmitter of hyperpolarization inhibition in the brain cortes is gamma-aminobutyric acid (GABA). (II) The reinforcement and, after a few combination with it, a conditional stimulus call the activation of electroencephalogram (EEG). On the background of activation EEG take place the transfer of neurons from chaotic or irregular group action potentials to the next forms activity: (1) the acceleration of action potentials, (2) tonic flows of impulses due to decreasing of inhibitory pauses and postinhibitory activation, in other words, disinhibition, (3) tonic inhibition of action potentials in brain cortex, (4) the most part of neurons of hippocampus and other structures of limbic system works in the rhythm theta--5-7 c/sec on the background of activation of EEG. (III) The glutamatergic neurotransmitter system plays the important role in the transmission of "modal-specific" influences of conditional and unconditional stimuli. The cholinergic and other neurotransmitter systems take part in the transmission of "modal-nonspecific" influences. (IV) The tonic inhibition that appears by EEG activation, it may be, plays the important role in realization of external inhibition. (V) Neurophysiological and neurotransmitter basis of behavioral disinhibition, presumably, can have several reasons: (1) a simple exceeding of excitatory influences over inhibitory one, (2) "the inhibition of inhibition", (3) "depolarization induced suppression of inhibition" (DSI).

The role of traditions, revision of dogmatic concepts, and emergence of novel theories in the investigations of the vertebrate brain evolution on the bases of modern neuroscientific data represent the objective of the present paper. Problems of homology, encephalization, recapitulation, dissolution, and the significance of their revision for understanding the brain evolution are considered. Arguments for equal importance in studying consequences of both phylogenetic and divergent adaptive evolution are presented. Comparative study of functional mechanisms is suggested as a perspective trend of the evolutionary physiology. It will be a valuable tool both for understanding the brain evolution and for applied investigations in neurobiology and medicine.

In the paper, the mechanism of forming of rhythmic slow-wave fluctuations in craniospinal cavity was investigated. In five young healthy persons, at rest and under voluntary respiration arrest test, the bioimpedansograms of head and lumbosacral part of vertebral column were synchronously registered as these recordings reflect the changes of relationships between blood/CSF volumes in cranial and lumbosacral regions, respectively. The recordings were subjected to frequency and spectral computer analysis (PC Macintosh G-4, Chart 5.2. software). The rapid (pulsatile) as well as slow and counter-directed waves (frequency 6-10 cycles/min) of these processes were revealed in cranial and lumbosacral regions. The data obtained suggest the CSF dynamic concept of origin of the craniosacral rhythm. The pulse and slow-frequency oscillations of the cerebral vessels tone initiate corresponding intracranial pressure waves, and the latter are the motivating forces for to-and-fro CSF shifts in caudal direction. This mechanism is accompanied by tonic contractions of lumbar muscles and sacrum movements, and it is manually perceptible as a craniosacral rhythm.