[About rare causes of the loss of hearing].

The present paper reports a clinical case of local syphilitic meningoencephalitis known as Argyll-Robertson syndrome and manifested in the form of acute sensorineural loss of hearing. The patient was a 46 year old resident of the city of Irkutsk. He experienced the sharp impairment of hearing involving both ears with the accompanying feeling of dizziness, disturbed orientation of the locomotorbehaviour, the lurching gate, subfebrility, the loss of the ability to speak and write. The diagnosis was based on the presence of anisocoria, the absence of consensual pupillary reaction to the light, weak atropine action on the pupils, well expressed positive results of the VRDL (blood) and RW (liquor) tests, an enhanced signal from the left temporal region in the T-2 regime during MRI, positive hearing dynamics within 12 hours after the onset of anti-inflammatory, antibacterial and infusion therapy. The specific feature of the clinical case being considered is differential diagnostics was performed with the purpose of distinguishing it from otogenic brain abscess associated with chronic left-hand mesotympanitis.

[Effect of succinate-containing solution on the level of metabolism during perioperative period in children].

DESIGN: A randomized prospective study. PATIENTS AND METHODS: The study included 87 children aged from 5 to 18, ASA I-II. The patients were divided into two groups. We assessed the impact of reamberin 1.5% (succinate-containing infusion solution) on the level of metabolism and recovery after surgery in patients of main group (n = 44) and control group (n = 43) during different surgeries. All patients received general anaesthesia with sevoflurane, fentanyl, and rocuronium. RESULTS: Reamberin 1.5% promotes to increase the level of basal metabolism in the early postoperative period, decreases the duration of awakening periods, improves recovery of motor activity and adequate breathing.

[Haemodynamics during kidney transplantation and general anaesthesia in combination with epidural block and without it in pediatric patients].

RESEARCH OBJECTIVE: To compare haemodynamic effects of general anaesthesia in combination with epidural block and without it during kidney transplantation in Pediatric patients. METHODS: 61 Pediatric patients undergoing kidney transplantation were divided into two groups. General anaesthesia with sevoflurane, propofol, phentanilum and regional ropivacaine epidural block were used in the group 1. General anaesthesia was used only in the group 2. Haemodynamic parameters were assessed: Arterial blood pressure, stroke volume, central venous pressure and cardiac index. RESULTS: Both techniques of anaesthesia were adequate. CONCLUSION: regional ropivacaine epidural block and general anaesthesia combination provides more stable haemodynamic parameters than general anaesthesia single use.

[Oxygenation state of brain in children upon reamberin infusion during post-anesthesia recovery].

The effect of reamberin (1.5% solution of succinic acid and ion complex) on the oxygenation status of the brain was studied in children aged 1 - 14 years during recovery from anesthesia. It is established that reamberin in a dose of 2 ml/kg administered twice at the end of an operation increases the fraction of oxidized hemoglobin and cytochrome oxidase and enhances the regional saturation of brain tissue with oxygen, which is indicative of an increase in the potential of metabolism activation in neurons.

[Reamberin administration for early postnarcosis recovery in children].

The possibility of using 1.5% succinic acid solution (reamberin) in order to activate recovery from anesthesia was studied in a group of 91 patients aged 1-14 years. Based on clinical data and BIS-index, it is established that the administration of reamberin during exit from anesthesia stage shortens the wake-up period, decreases the time of restoration of the motor activity and adequate respiration, and accelerates brain function recovery.

[Postoperative infusion therapy in children].

The study investigates the influence of Voluven 6% and HAES-steril 10% on the hemodynamics and organism water balance of 40 children from 3 months to 17 years of age, which were divided into two groups according to the type of the administered colloid. It is acquired that infusion of colloids with 1:3 ratio compared to crystalloids in general volume of infused liquids (Voluven 6% in the dose of 5 ml/kg/hour in case of median blood loss of 15% of the total circulating blood volume during two hour long surgery and HAES-steril 10% in the dose of 4 ml/kg/hour in case of the blood loss up to 25% of TCBV) allows to effectively neutralize hemodynamic changes based upon administration of anesthetic agents and intraoperative fluid loss. While administration of Voluven 6% is accompanied by significant, statistically accurate decrease of lower limb impedance, which indicates the increased amount of water in them, HAES-steril 10% administration leads to redistribution of water in the body segments with its predominant significant increase in the torso.

[Pharmacokinetics of fentanyl during sevoflurane based general anesthesia in children].

The research is based on the analysis of 50 cases of anesthesia during reconstructive surgeries in children. The anesthesia was based on inhalation of sevolflurane and injection of fentanyl by the bolus infusion scheme. During the different stages of anesthesia the opioid concentration in plasma was measured. Analysis of hemodynamic parameters showed no statistically significant differences in changes in performance, indicating the steady flow of anesthesia. Infusion of fentanyl provided a smooth, gradual decrease in its concentration in plasma, while analgesia remained adequate. The combination of sevoflurane in a concentration of 1.3 MAC and infusion of fentanyl to a total dose 6 mkg/kg/h was effective in provisioning stable anesthesia in the given category of patients with surgical pathology.

[Postanesthetic agitation syndrome after inhalation anesthesia with sevofluorane in children].

The paper analyzes the publications dedicated to the problem of agitation after inhalation anesthesia with sevofluorane. A brief explanation of the conception "agitation" is given in the context of interpretation of explanatory and psychological dictionaries. According to most of the analyzed papers, it is concluded that the incidence of the postanesthetic agitation syndrome occurs after anesthesia with sevofluorane than after that with halothane. The leading risk factors of agitation are preschool age, significant psychoemotional lability in the preoperative period (difficult parting with parents), fear. The efficiency of the preventive measures given in the analyzed paper is disputable. These include opioids (fentanyl), benzodiazepines (midasolam), clonidine, ketamine, dexmedotomidine, nitrous oxide, propofol, etc. The authors conclude that this problem is of no high significance in the aspect of priority, the width and safety of sevofluorane use in the anesthetic maintenance of children although it by far needs further more detailed study.

Experimental-design Specific Changes in Spontaneous EEG and During Intermittent Photic Stimulation by High Definition Transcranial Direct Current Stimulation.

Electroencephalography (EEG) as a biomarker of neuromodulation by High Definition transcranial Direct Current Stimulation (HD-tDCS) offers promise as both techniques are deployable and can be integrated into a single head-gear. The present research addresses experimental design for separating focal EEG effect of HD-tDCS in the '4-cathode × 1-anode' (4 × 1) montage over the left motor area (C3). We assessed change in offline EEG at the homologous central (C3, C4), and occipital (O1, O2) locations. Interhemispheric asymmetry was accessed for background EEG at standard frequency bands; and for the intermittent photic stimulation (IPS). EEG was compared post- vs pre-intervention in three HD-tDCS arms: Active (2 mA), Sham (ramp up/down at the start and end), and No-Stimulation (device was not powered), each intervention lasting 20 min. The asymmetric background EEG changes were only in the central areas with right-side amplitude spectra prevalence, most pronounced in the no-stimulation arm, where they depended on comparison time-points and were consistent with markers of transition between drowsiness and vigilance - bilateral decrease in the delta and asymmetric central increase in the alpha and beta1 bands. For the active arm, similar but less pronounced changes occurred in the alpha band. In contrast, responses to IPS developed similar asymmetric amplitude increase at four harmonics of the IPS of 3 Hz only in the active arm, against a background of a brain-wide symmetric increase in both active and sham arms. Our protocols and analyses suggest methodological caveats for how EEG of tDCS studies could be conducted to isolate putative brain polarization outcomes.

[EEG bispectral index as an indicator of the electrical activity of the central nervous system in children during anesthetic maintenance and intensive care].

The paper presents different investigators' data on the use of the bispectral (BIS) index in children during anesthetic maintenance and intensive care. The most of publications deal with the use of the BIS index during anesthesia with sevoflurane, which shows its high efficiency in estimating the depth of sleep. There are positive aspects in the use of the BIS index in the evaluation of sedative tolerance and central nervous system function, when brain death is diagnosed, cerebral oxygenation adequateness, etc. Data are given on the ambiguity of BIS index values in infants less than a year of age.

Liquid crystal as laser medium with tunable gain spectra.

Amplified spontaneous emission intensity and gain spectra in polarized light have been measured in a dye doped nematic liquid crystal for different orientation of its optical axis and pump intensity. A possibility for switching the gain of the liquid crystal by an external electric field is shown experimentally. The liquid crystal materials with field controlled gain can be used in microlasers and light micro-amplifiers in both planar and waveguiding geometry.

[Effect of volatile inhalational anesthetics on cerebral blood volume and oxygen status in children].

The investigation evaluated the effect of various volatile anesthetics on cerebral blood volume and oxygen status in sick children at the stage of anesthesia induction. Ninety-two children were distributed into 3 groups: Groups 1 (n = 36) and 2 (n = 24) underwent stepwise induction with halothane and enflurane, respectively. Group 3 (n = 32) had vital capacity rapid inhalation induction with sevoflurane. Cerebral oximetry (NIRS method) was used to measure the content of hydroxyhemoglobin, deoxyhemoglobin, the total level of hemoglobin and to assess regional cerebral tissue saturation (rSO2). Halothane was ascertained to increase cerebral blood volume by 20.5% whereas enflurane and sevoflurane increased it only by 8.8 and 9.0%, respectively. In all cases, the value of rSO2 remained comparatively high, by exceeding the baseline level by 3-5%.

[Central and cerebral hemodynamics during gynecological laparoscopic interventions in children].

The authors examined central and cerebral hemodynamics in children during gynecological laparoscopic interventions. The course of 64 anesthesias was analyzed in girls aged 3 to 16 years, who had undergone laparoscopic surgery. Central hemodynamics was studied by tetrapolar rheography on a Diamant apparatus; cerebral oximetry was examined on a Critikon RedOx Monitor 2020 device. The findings demonstrate that pneumoperitoneum application causes immediate cardiovascular changes. Transfer of patients to Trendelenburg's position had a beneficial impact on central hemodynamics, by facilitating the normalization of venous return, thus maintaining cardiac output. Central hemodynamic disorders promptly affected cerebral blood volume and oxygen status. After pneumoperitoneum application, there was an average of 3% reduction in regional cerebral tissue saturation.

[Temperature balance and the possibility of its maintenance during general anesthesia in children].

The problems of hypothermia in the perioperative period, which are one of the most important ones in pediatric practice, in babies in particular, are solved, by using a broad spectrum of methods for preventing and correcting the patients' thermal balance. Convection heating systems exercise an on-line control over the baby's thermal regime during a surgical intervention and intensive care. The authors' own experience allows these systems to be recommended for wide practical application in the activities of anesthesiology and intensive care services.

Fluorescent diagnostics of human gastric cancer and sodium fluorescein accumulation in experimental gastric cancer in rats.

Patients (459) with chronic gastritis, ulcers, polyposis and different types of gastric cancers were examined by endoscopic fluorescent technique using a special drug based on the sodium salt of fluorescein (F1). Eighty-five percent of gastric cancers showed positive fluorescence. The F1 distribution in the stomach of the rat with induced gastric cancer was examined. In all cases the level of F1 fluorescence in the tumor was higher than in the adjacent normal tissues of the stomach. Thus, all the obtained results confirm the selective accumulation of F1 in tumors of the stomach.

On the intercorrelation of some frequency and amplitude parameters of the human EEG and its functional significance. Communication II: neurodynamic imbalance in endogenous asthenic-like disorders.

In 67 borderline psychiatric patients suffering from schizotypal/slowly developing schizophrenic disorders and 18 patients suffering from cyclothymia, the factor structure of the period (interval-amplitude) parameters of the EEG proved to be similar to that obtained in normal subjects during mental activity and reported in part I (Lazarev, Int. J. Psychophysiol., 28 (1998) 77-98). However, 51 patients with schizotypal disorders with a predominance of asthenic-like symptomatology, characterized by mild thought disorders with difficulty in focusing attention, were distinguished from normal subjects, cyclothymic patients and other patients of schizotypy without well-defined asthenic symptoms by significantly increased values of EEG Factor II which was positively related to the index-presence in epoch, frequency and regularity of low-amplitude beta-waves, and reduced values of an EEG Factor III which was positively correlated with mean alpha-period and theta-index. According to normative data (part I; Lazarev, Int. J. Psychophysiol., 28 (1998) 77-98), this probably reflects a neurodynamic imbalance between an excess of 'cortical excitation' (Factor II) and a deficit of 'active selective inhibition' (Factor III). This imbalance appears to be opposite to the changes in values of these factors found in normal subjects during focusing attention and motor automation, when compared with relaxed wakefulness. The functional properties of Factors II and III ascribed on the basis of psychological testing suggest that such an imbalance could reflect a predominance of successively organised associative mental processes over the selective inhibition of irrelevant associations. This could cause difficulties in voluntary attention, mental automation and in the performance of simultaneous mental operations. In most cases, there was no difference in Factor I which was positively related to the index, amplitude and regularity of alpha-activity and wave amplitudes in other bands, and negatively related to the indices and mean periods of delta- and theta-waves, the factor presumed to depict 'general activation'.

On the intercorrelation of some frequency and amplitude parameters of the human EEG and its functional significance. Communication. I: Multidimensional neurodynamic organization of functional states of the brain during intellectual, perceptive and motor activity in normal subjects.

In 95 normal subjects, a separate evaluation of the amplitude and frequency parameters of EEG by period analysis made it possible to reveal, using factor analysis, four independent groups of parameters--the EEG factors, two of which being independent of the amplitude fluctuations. They were considered as integral EEG characteristics of qualitatively different neurophysiological processes. Decrease of Factor I values during mental activity (called 'general activation') reflected an intercorrelated desynchronization of the wave amplitudes in all the bands, a decrease of alpha-index (percentage presence in epoch) and regularity together with parallel increase of the indices and mean periods of delta- and theta-waves. This generalized reaction has shown 'non-specific' dependence upon novelty and difficulty of the tasks and stimuli with certain task-specific topographical distribution. An increase of values of regional Factor Ia in the anterior areas was caused by delta- and theta-amplitude synchronization, more pronounced during matching the rhymes (MR) than in mental multiplication (MM). An increase of Factor II values (related to increase of the index, frequency and regularity of beta-activity and called 'cortical excitation', CE) was more expressed during MR, whereas an increase of Factor III values (an increase of mean alpha-period and theta-index called 'active selective inhibition', ASI) was characteristic of MM, the latter reaction being evident in the right hemisphere. During analysis of external sound stimuli and rhythmical clenching of a fist, an increase of Factor III values was accompanied by decrease of Factor II values [corrected]; in the motor activity, such reciprocal reaction being localized in the central areas contralateral to the hand moved . Neuropsychological analysis suggests that CE correlates with associative and successively organized mental operations involving search for memory traces and ASI presumably relates to different aspects of mental selectivity such as simultaneous mental operations, voluntary attention and mental automation, the latter two cases being supported by parallel reduction of CE.

Topographic aspects of photic driving in the electroencephalogram of children and adolescents.

The electroencephalogram amplitude spectra at 11 fixed frequencies of intermittent photic stimulation of 3 to 24 Hz were combined into driving "profiles" for 14 scalp points in 8 male and 7 female normal subjects aged 9 to 17 years. The driving response varied over frequency and was detected in 70 to 100% of cases in the occipital areas (maximum) and in 27 to 77% of cases in the frontal areas (minimum) using as a criterion peak amplitude 20% higher than those of the neighbors. Each subject responded, on average, to 9.7 +/- 1.15 intermittent photic stimulation frequencies in the right occipital area and to 6.8 +/- 1.97 frequencies in the right frontal area. Most of the driving responses (in relation to the previous background) were significant according to the spectral F-test (alpha = 0.05), which also detected changes in some cases of low amplitude responses not revealed by the peak criterion. The profiles had two maxima in the alpha and theta bands in all leads. The latter was not present in the background spectra in the posterior areas and was less pronounced in the anterior ones. The weight of the profile theta maximum increased towards the frontal areas where the two maxima were similar, while the profile amplitudes decreased. The profiles repeated the shape of the background spectra, except for the theta band. The interhemispheric correlation between profiles was high. The theta driving detected in all areas recorded suggests a generalized influence of the theta generators in prepubertal and pubertal subjects.

Photic driving in the electroencephalogram of children and adolescents: harmonic structure and relation to the resting state.

In order to identify latent bioelectrical oscillators, 15 normal subjects (aged 9-17 years, 8 males, 7 females) were subjected to intermittent photic stimulation. The EEG amplitude spectra corresponding to the 11 fixed frequencies of stimulation presented (3-24 Hz) were combined to form "profiles" of the driving reaction in the right occipital area. The driving response varied with frequency, and was demonstrable in 70-100% of cases (using as criterion peak amplitudes 20% larger than those of the neighbors). The strongest responses were observed at the frequency closest to the alpha peak of the resting EEG. A secondary profile maximum was in the theta band. In 10 subjects, this maximum exceeded half the alpha peak (with an average of 72.4% of the alpha peak), while in the resting spectra, theta amplitudes were much lower than the alpha maxima. This responsiveness in theta activity seems to be characteristic of prepubertal and pubertal subjects. The profiles and resting EEG spectra showed a highly significant Pearson's correlation, with the peak in the theta band of the profiles being the main difference observed between them. The correlation coefficient was significantly correlated with the ratio of the maxima in the theta and alpha bands (R = -0.77, P<0.001). The correlation coefficient between profile and resting spectrum may be a useful indicator in screening methods used to reveal latent cerebral oscillators. Profiles for the second and third harmonics were correlated with those of the first harmonic (fundamental frequency), when considering the corresponding EEG frequencies. Peak frequencies in all three profiles were close to those of the individual's background alpha rhythm, and peak amplitudes in higher harmonics were not much lower than those of the fundamental frequency (mean values of 84 and 63%, for second and third harmonics, respectively).

Sodium fluorescein accumulation in cultured cells.

The mechanism of intracellular fluorescein accumulation was investigated by studying fluorescein accumulation kinetics in individual cells in culture. The experiments were done with K562 human erythroleukemia cell culture and a primary culture of human embryonic skin fibroblasts. Various experimental conditions were used by varying pH and ion composition of the external media, and/or temperature. All the experimental results obtained are in support of the proposed theoretical model describing fluorescein accumulation in cells along the pH gradient. In addition, we could show that fluorescein molecules are bound to some intracellular macromolecules. Fluorescein accumulation in the cells studied does not depend on their malignant nature. It is therefore reasonable to conclude that fluorescein accumulation observed in clinical investigations of human gastric cancer is governed by the ph gradient between the cells and the extracellular fluid; this gradient is much greater in the tumor than in normal tissues.