[Cognitive disorders in burnout syndrome]. / Kognitivnye narusheniya pri sindrome emotsional'nogo vygoraniya.

OBJECTIVE: To study the impairment of cognitive functions in patients with different stages of the burnout syndrome (BS). MATERIAL AND METHODS: 78 patients aged 25-45 years (average age 36.9±9.5 years) were examined, which at the BS stage were divided into two subgroups: Residence (51.3%, n=40) and Exhaustion (48.7%, n=38). The control group consisted of 106 practically healthy (average age 36.3±7.2 years) The following methods were used: Russian-language version of the MBI questionnaire, questionnaire to diagnose the level of emotional burnout by V.V. Boyko, questionnaire CFQ, method «Learning 10 words¼ by A.R. Luria, registration of cognitive evoked potentials (EP) in the psychophysiological visual test VCPT. RESULTS: Subjective symptoms of memory loss were in 47 patients (60.3% of the total number of patients with EBS): 17 patients (42.5%) from the subgroup Resistance and 30 patients (78.9%) from the subgroup Exhaustion. The quantitative evaluation of the subjective symptoms in the CFQ test showed a reliable increase in all patient groups (p<0.05) and especially in the subgroup Exhaustion. There was statistically reliable decrease of the P200 component in subgroup Resistence and control group in the alloys Cz (p<0.001) and Fz (p<0.001), as well as statistically reliable reduction of the P300 component in the indicated leads (Cz (p<0.001) and Pz (p<0.001)) in patients in the subgroup Resistance. Most BS patients had cognitive complaints that were more common at the Exhaustion stage. At the same time, objective cognitive impairments were detected only in patients at the stage of Exhaustion. Only the long-term memory is affected. Psychophysiological research has shown a decrease in the level of attention in both subgroups, which demonstrated an increased impairment of mental processes. CONCLUSION: Cognitive impairment in patients with BS manifests in various forms of attention, memory impairment, and performance degradation in the resistance and exhaustion phases, and can result from high asthenization.

Structure and antibacterial properties of Ag-doped micropattern surfaces produced by photolithography method.

Photolithography methods offer ample opportunities for creating biological surface patterns over large areas. Herein, samples with patterned surface having the same Ag total coverage area and content, but different surface topography made of periodically spaced Ag/Si pillars with a diameter of 10 and 50 µm and a height of 3, 1, and 0.2 µm were produced by photolithography technique and studied to uncover the dependences of bactericide ion release on surface topography and antibacterial effect on Ag+ ion concentration. Reactive ion etching of Si wafers in areas unprotected by Ag capping layer was accompanied by a number of competing processes: (i) formation of Ag particles on the tops of pillars due to temperature-activated diffusion and coalescence, (ii) sputtering of Ag from the pillar to surface and redeposition into the etching cavities, resulting in the formation of small Ag nanoparticles located in areas between pillars, (iii) precipitation of AgSix phase as a result of chemical interaction of sputtered Si ions with Ag ions and atoms in surrounding plasma. Samples with the largest pillar heights which had also Ag particles formed between pillars demonstrated the fastest Ag+ ion release and, correspondingly, a noticeable antibacterial effect toward antibiotic-resistant hospital Escherichia coli K-261 strains already after 3 h. All samples showed 100% antibacterial effect after 24 h. Thus our results open up new possibilities for the production of scalable micropattern surfaces with controlled bactericide ion release and pronounced antibacterial characteristics for future applications in the orthopedic field.

Antibacterial Performance of TiCaPCON Films Incorporated with Ag, Pt, and Zn: Bactericidal Ions Versus Surface Microgalvanic Interactions.

It is very important to prevent bacterial colonization at the early postoperative stages. There are four major strategies and their corresponding types of antibacterial surfaces specifically designed to fight infection: bactericide release, anti-adhesion, pH-sensitive, and contact-killing. Herein, we aimed at determining the antibacterial efficiency of different types of bactericidal ions and revealing the possible contribution of surface microgalvanic effects arising from a potential difference on heterogeneous surfaces. We considered five types of TiCaPCON films, with Ag, Zn, Pt, Ag + Zn, and Pt + Zn nanoparticles (NPs) on their surface. The Ag-modified film demonstrated a pronounced antibacterial effect at a very low Ag ion concentration of 0.11 ppb in physiological solution that was achieved already after 3 h of immersion in Escherichia coli ( E. coli) bacterial culture. The Zn-containing sample also showed a noticeable antibacterial effect against E. coli and Staphylococcus aureus ( S. aureus) strains, wherein the concentration of Zn ions was 2 orders of magnitude higher (15 ppb) compared with the Ag ions. The presence of Ag NPs accelerated the leaching of Zn ion out of the TiCaPCON-Ag-Zn film, but no synergistic effect of the simultaneous presence of the two bactericidal components was observed. After the incubation of the samples with Ag, Zn, and Ag + Zn NPs in E. coli and S. aureus suspensions for 24 and 8 h, respectively, all bacterial cells were completely inactivated. The Pt-containing film showed a very low Pt ion release, and therefore the contribution of this type of ions to the total bactericidal effect could be neglected. The results of the electrochemical studies and Kelvin probe force microscopy indicated that microgalvanic couples were formed between the Pt NPs and the TiCaPCON film, but no noticeable antibacterial effect against either E. coli or S. aureus strains was observed. All ion-modified samples provided good osteoblastic cell attachment, spreading, and proliferation and therefore were concluded to be nontoxic for cells. In addition, the TiCaPCON films with Ag, Pt, and Zn NPs on their surface demonstrated good osteoconductive characteristics.

[Event-Related Potentials in Schizotypal Personality Disorder and Schizophrenia.]

The article presents an analysis of event-related potentials in Go/NoGo test from patients with schizophrenia and schizotypal personality disorder relative to healthy subjects. Identified differences in the group of patients with schizophrenia are consistent with previous studies and indicate a violation of the processes associated with different stages of visual information processing and executive functions. Special features of the brain activity from patients with schizotypal personality disorder were significantly less pronounced, and, presumably, pointed on the changes in the processes of attention redistribution and action monitoring. The results agree well with the clinical symptoms of schizophrenia and schizotypal personality disorder that allows us to consider this technique as a possible additional diagnostic criterion of these disorders.

[Analysis of independent components for event-related potentials from patients with an established diagnosis of schizophrenia, obsessive-compulsive and depressive disorders].

We investigated the possibility to classify data from patients with different psychiatric disorders on the base of physiological measures of the brain activity. Event-related potentials during the execution of GO/NOGO task were recorded from age matched groups of patients with schizophrenia, major depression and obsessive-compulsive disorder. Separation of independent components for event-related potentials was performed by applying Independent Component Analysis method. Picked out components were used in the method of discriminant analysis to classify the data according to clinical diagnosis. Discriminant analysis of components for event-related potentials allows classifying the data of patients with a suitable amount of matches with an established diagnosis.

[Functional biomarkers in the diagnostics of mental disorders: cognitive event-related potentials].

The article is devoted to recent researches in the field of fundamental knowledge about the mechanisms of information processing in human brain for the diagnosis of mental disorders performed in the laboratory of neurobiology for action programming of the Bechtereva Institute of Human Brain, RAS. These researches were connected with analysis of functional components for cognitive ERPs obtained in diverse behavioral conditions. The main goal of this fundamental approach is the decomposition of multi-channel ERPs into functionally different components. These components are generated in various cortical areas have different temporal dynamics and reflect a variety of mental operations. The main methodology we used is the independent component analysis, applied to a large set of ERPs (from hundreds of people) obtained by varying of functional conditions in one psychological test. In particular, components related to psychological processes such as the comparison of sensory signals with the trace in working memory, inhibition of current activity, monitoring of the conflict were identified in the GO/NOGO test. In the framework of European project normative database was constructed for the components described above and this allowed comparing the data obtained from large groups of patients (including patients with attention deficit disorder, schizophrenia, obsessive disorders, depression, autism, dyslexia, brain trauma and dementia) with the healthy subjects. This article presents data from patients with a diagnosis of attention deficit disorder and schizophrenia.

[Power spectra of the main EEG rhythms in children with different types of attention deficit hyperactivity disorder].

We investigated a group of children aged 9-12 years with attention deficit hyperactivity disorder (ADHD) combined type, have divided into two variants of the clinical picture of ADHD: residual-organic variant (ADH D RO) and idiopathic variant (ADHD RI). We studied the power spectral analysis in the main frequency bands in background EEG eyes closed and are open. The significant differences between both groups observed in the theta frequency band in the fronto-central and occipital leads. In the fronto-central leads of the cortex were the maximum values in the group of children ADHD RO, whereas in children with ADHD IR, the largest values of power spectra were in the occipital leads. Statistically significant differences in spectral power in the alpha range between healthy subjects and groups children with ADHD had not been received. Thus, our studies have shown that these two variants of ADHD have some neurophysiological differences that must be considered when choosing a treatment.

[Improving source localization of ERPs in the GO/NOGO task by modeling of their cross-covariance structure].

We studied 19-channel event-related potentials (ERPs) during the GO/NOGO task in 517 healthy subjects. Decomposition of multi-channel ERP into independent components was performed with a method based on modeling the cross-covariance structure of the transient response. The results show that this method allows us to obtain low-correlated components with acceptable reliability. The identified components have been associated with psychological processes such as the attended sensory mismatch operation, the decision-making on the subsequent action, the action inhibition operation, the conflict monitoring operation and others. In conclusion, the separation of the ERP recording into independent components and the use of the sLORETA helps localizing sources of ERPs more accurately than the conventional analysis of the ERP.

[Developmental features of the brain bioelectrical activity in children with remote consequences of a perinatal lesion of the CNS. II. EEG typology in normal and mental disorders].

This research represents EEG - investigation by children with remote consequences of perinatal CNS pathology. Its described the different EEG types in normal and mental disorders in children. Its showed a early EEG - markers of abnormal ontogenesis in longitudinal study. The data obtained gives to prevent a negative dynamic of mental and speech development (learning disability, motor alalia, autism).

[Analysis of EEG characteristic at early stages of depression using method of independent components].

Independent Component Analysis (ICA) was used for 19-channel resting EEG analysis 111 patients at early stages of depressive disorder and 526 age-matched healthy subjects. Comparison of independent components power spectra in depressed patients and healthy subjects in two states: Eyes closed and Eyes open, has revealed significant differences between groups for three frequency bands: Theta (4-7.5 Hz), Alpha (7.5-14 Hz), and Beta (14-20 Hz). Increased power of alpha and theta activity in depressed patients at parietal and occipital sites may be caused by decreased cortical activation of these regions. Diffuse enhancement of beta activity level can correlate with anxiety symptoms which take an important place in clinical picture of depressive disorder at early stages. Using of ICA method for comparison of spectral characteristics of EEG in groups of patients with different brain pathology and healthy subjects gives a possibility to localize more precisely the discovered differences as compare to traditional analysis of EEG spectra.

[The comparison of clustering methods of EEG independent components in healthy subjects and patients with post concussion syndrome after traumatic brain injury].

The comparison of three different clustering methods of 19-channels EEG independent components in 518 healthy subjects and 87 patients with post concussion syndrome after traumatic brain injury was performed to define more exact the location of sources of pathologic brain activity. Following methods of grouping were used: clustering of independent components topographies, clustering of coordinates of equivalent dipole sources corresponding to independent components topographies and sorting of independent components using extremes of equivalent source current density computed by Standardized Low Resolution Electromagnetic Tomography (sLORETA).The comparison of power spectra of independent components revealed statically significant increase of EEG power located in frontal and temporal brain areas in delta, theta and alpha frequency bands in patients with post concussion syndrome after traumatic brain injury. The method of clustering of independent components topographies seems to be most sensitive in comparison with other two methods.

[Normative EEG spectral characteristics in healthy subjects from 7 to 89 years].

EEGs were recorded at 885 healthy subjects of both sexes with age from 7 to 89 years in "eyes closed" and "eyes opened" conditions. Both average EEG power spectra and EEG independent component power spectra were computed for 20 age groups of subjects separately, and corresponding confidence intervals of average power were estimated for four frequency bands: delta, theta, alpha and beta. These quantitative data can be useful as objective criteria for diagnostics of brain dysfunctions.

[Mortality after surgical treatment of patients with hypertensive intracerebral hematomas].

Authors summarized the experience of specialized neurosurgical clinic for treatment of patients with stroke. From 1998 till 2008 1035 patients with hypertensive intracerebral hematomas were examined and treated in the clinic. 635 patients were operated, 400 received conservative treatment. Volumes of hematomas varied from 3 to 130 ml. Mean volume of hematoma in the "surgical" group was 52.9 ml (SD = 23.1), in the "conservative" group -- 37.2 ml (SD = 22.9). Two types of indications for surgery were defined: a) indications for life-saving surgery; b) indications for surgical treatment, implying achievement of good functional result. Hematomas were removed using different techniques: craniectomy or craniotomy -- 123 patients; minimally-invasive craniotomy and limited encephalotomy -- 78; puncture aspiration -- 65; puncture aspiration combined with local fibrinolysis (prourokinase) -- 291; combined procedures (including endoscopic) -- 49; external ventricular drainage -- 29. 30-days mortality in the "surgical" group was 29%, in the "conservative" group -- 38.7%. Critical volumes of hematomas of different localization with maximal effect on mortality were distinguished. Main causes of lethal outcome in the "surgical" group were the following: pulmonary artery thomboembolism -- 21.5%, pneumonia -- 29%, recurrent hemorrhage -- 19.5%. Therefore, surgical management of hypertensive intracerebral hematomas in selected groups of patients is associated with lower rate of mortality, in comparison with conservative management. Basically, it refers to the patients in severe condition, with volumes of hematoma above critical limits specific for certain localization.

[Methods of localization of equivalent EEG sources in the diagnostics of protracted loss of consciousness].

Results of EEG study of patients in a protracted unconscious state due to severe cranial trauma using different methods of source localization (independent component analysis, the LORETA method) are presented in order to compare their diagnostic value. Also the results of the study of somatosensory evoked potentials (SSEP) to median nerve stimulation of and EEG are compared. The independent higher frequency components of the EEG power spectrum had the higher activity in the delta-band, were localized predominantly in the frontal brain hemispheres (frontal, temporal regions), positively correlated with pathological neurodynamic SSEP changes (r=0,69; p=0,003) and negatively with the scores on the Glasgow outcome scale (r=-0,66; p=0,005).

[Local fibrinolysis of hypertensive intracerebral hematomas].

Authors presented the results of experimental and clinical studies of effects of recombinant prourokinase on brain tissue, its toxicity and safety in intracerebral administration for lysis of hypertensive intracerebral hematomas. Experiments were performed in 64 rabbits. Histological specimens were examined in different periods after injection of prourokinase into white matter and into experimental hematoma. It is revealed that dose of 615 mg/kg causes minimal changes in cerebral tissue. Clinical study was based on analysis of puncture aspiration of intracerebral hematomas with local fibrinolysis performed in 275 patients with hemorrhagic stroke. Dynamics of MRI, clinical and laboratory parameters, coagulation, analysis of aspirated products of lysis were assessed. Authors showed that recombinant prourokinase and the drug "Puroplazan" are effective for local fibrinolysis. The drugs are non-toxic and non-allergenic and do not cause cerebral edema.