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Journal Article 2016; 37(1): 33-40 PubMed PMID: 26994383 Citation  Keywords:  Aged, Anesthesia, General, Anesthetics, Inhalation:pharmacology, Consciousness:drug effects, Delta Rhythm:drug effects, Dominance, Cerebral:drug effects, Female, Gamma Rhythm:drug effects, Humans, Intraoperative Neurophysiological Monitoring, Male, Middle.   

OBJECTIVES: The main objective was to indicate sufficient general anaesthesia (GA) inhibition for negative experience rejection in GA.

PATIENTS AND METHODS: We investigated the group of patients (n = 17, mean age 63.59 years, 9 male--65.78 years, 8 female - 61.13 years) during GA in open thorax surgery and analyzed EEG signal by power spectrum (pEEG) delta (DR), and gamma rhythms (GR). EEG was performed: OPO - the day before surgery and in surgery phases OP1-OP5 during GA. Particular GA phases: OP1 = after pre- medication, OP2 = surgery onset, OP3 = surgery with one-side lung ventilation, OP4 = end of surgery, both sides ventilation, OP5 = end of GA. pEEG registering in the left frontal region Fp1-A1 montage in 17 right handed persons.

RESULTS: Mean DR power in OP2 phase is significantly higher than in phase OP5 and mean DR power in OP3 is higher than in OP5. One-lung ventilation did not change minimal alveolar concentration and gases should not accelerate decrease in mean DR power. Higher mean value of GR power in OPO than in OP3 was statistically significant. Mean GR power in OP3 is statistically significantly lower than in OP4 correlating with the same gases concentration in OP3 and OP4.

CONCLUSION: Our results showed DR power decreased since OP2 till the end of GA it means inhibition represented by power DR fluently decreasing is sufficient for GA depth. GR power decay near the working memory could reduce conscious cognition and unpleasant explicit experience in GA....

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Comparative Study 2014; 35(4): 274-279 PubMed PMID: 25038600 Citation  Keywords:  Animals, Body Water:metabolism, Brain:metabolism, Cerebral Cortex:physiopathology, Disease Models, Animal, Electrophysiological Phenomena:physiology, Male, Neurons:physiology, Rats, Rats, Wistar, Water Intoxication:chemically induced,.   

OBJECTIVES: Our previous experiments with animal models revealed that water intoxication induces brain oedema and opens plasma membranes. Present study is aimed to determine whether the standard method of hyperhydration can influence cerebral microenvironment also in young rats. Neuronal functions were tested by standard electrical cortical stimulation.

METHODS: Hyperhydration was induced by administration of distilled water (DW) intraperitoneally. Three groups of young rats were used: 12, 25, and 35-day-old. Cortical excitability was tested 19 to 20 hours after DW administration by electrical stimulation of the sensorimotor cortex with intensity necessary to elicit cortical afterdischarges (AD). Water content in the brain was estimated by dry/wet ratio and value of natremia by standard biochemical examination. Control animals of the same age groups were tested in the same way, only they did not receive DW.

RESULTS: Brain water content in hyperhydrated animals was smaller than in controls in all studied age groups. Natremia was the same (normal) in both the hyperhydrated and control animals aged 25 days. Excitability of cortical neurons in young hyperhydrated animals was significantly inhibited in comparison to the same age groups of controls.

CONCLUSION: Hyperhydration induced in young rats (12, 25, 35-day-old) had different effects than in adults. Absence of hyponatremia, lower water content in the brain and significant inhibition of cortical excitability can be explained on the basis of ontogenetically dependent aquaporine expression (AQP 4) and different activity of ionic membrane transporters....

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Journal Article 2012; 33(4): 462-468 PubMed PMID: 22936254 Citation  Keywords:  Adaptation, Physiological, Automobile Driving, Biomechanical Phenomena, Case-Control Studies, Female, Humans, Pregnancy:physiology, Reference Values, Spine:physiology, Stress, Physiological:physiology, Vibration, Weight-Bearing:physiology,.   

OBJECTIVES: During a longer car drive there are changes in rheological properties of driver's or passenger's connective tissues taking place as a consequence of monotonous and vibration load. These changes show more among the pregnant drivers, whose motion system is under heavier demands due to pregnancy. To asses these changes we have used the TVS (transfer vibration through the spine) method.

METHODS: The TVS is based on application of γ excitation pulses with half-length 5 ms and then harmonic excitation continuously periodically changing from 5 Hz to 160 Hz on C7 and L5 vertebrae. This wave is transferred along the axial system and the acceleration of all the spinous tips of the vertebrae, along which the waves spread between C7 and S1, is detected by accelerometric sensors. The measurement was carried out on three drivers before and after a 4-hours driving. The same measurements of wave transfer along the spine with just one pregnant woman were carried out in th 16th, 26th and 32nd week of pregnancy. Consequently we constructed a simplified model of the spine in order to analyze gathered data by discovering elementary properties of the measured system.

RESULTS: After both vibration and physical load there is a more significant dampening of the spinal tissues apparent, i.e. lower acceleration amplitude and the tissues resonance frequency also shifts towards the lower frequencies. On the other hand after long lasting relaxation on a bed an opposite tendency showed, the acceleration amplitude was higher, tissues were relaxed and dampening was lower. The same tendency manifested among the pregnant women. The influence of progressing pregnancy on the spinal segment transfer function showed through a shifting of peaks above 20Hz. Their size also changes monotonously. An absorption area moves towards higher frequencies, rigidity of axial system connections grows.

CONCLUSION: The results say that drivers, including pregnant women, show changes in mechanical properties of examined tissues before and after vibration or other type of load. Or conversely before and after relaxation on a bed. Results of this work will be further analyzed, verified and evaluation procedures will be improved. We expect to find dependencies between excitation and resonance frequencies during the transfer via the axial system, the rheological properties of the axial system components and the physical nature of the load of the axial system. They are then going to be applicable for the prevention of injuries of the axial system, physiotherapy practices in the rehabilitation of post-operative conditions, the dosage of training loads of athletes, in determining the effects of job stress regimes and their prevention....

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Journal Article 2011; 32(Suppl 1): 131-136 PubMed PMID: 22167215 Citation  Keywords:  Animals, Dextran Sulfate, Drug Evaluation, Preclinical, Electromyography:methods, Electrophysiological Phenomena:drug effects, Erythromycin:administration & dosage, Female, Gastrointestinal Agents:administration & dosage, Gastrointestinal Diseases:chemica.   

OBJECTIVES: Electrogastrography (EGG) is a non-invasive investigation of gastric myoelectrical activity. The aim of study was to evaluate the impact of erythromycin on EGG in gastrointestinal toxic injury induced by dextran sodium sulphate (DSS) in experimental pigs.

METHODS: The experiments were carried out on 12 adult pigs (weighing 30-35 kg). EGG was recorded using Digitrapper equipment (Synectics Medical AB, Stockholm). Running spectrum activity was used for EGG evaluation. There were two groups of animals: Group I: 6 controls with erythromycin administration (1,600 mg intragastrically); Group II: 6 animals treated with DSS (for 5 days, 0.25 g/kg per day in a dietary bolus) followed by erythromycin administration. Baseline and subsequent six separate 30-minute EGG-recordings (from time 0 to 360 min) were accomplished in each animal.

RESULTS AND CONCLUSION: A total of 84 records were analysed. Baseline dominant frequency of slow waves was fully comparable in both groups. In Group I, there was a significant increase in dominant frequency after erythromycin administration (maximum between 240-360 min). There was a flat non-significant and delayed increase in dominant frequency after erythromycin administration in Group II. The difference between Group I and II at particular time intervals was not significant but a diverse trend was evident. EGG recording enables us to register a gastric myoelectrical effect of prokinetic drugs. Erythromycin induced a significant increase in the dominant frequency of slow waves. DSS caused toxic injury to the porcine gastrointestinal tract responsible for the delayed and weaker myoelectrical effect of erythromycin in experimental animals....

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Comparative Study 2011; 32(5): 691-696 PubMed PMID: 22167130 Citation  Keywords:  Adaptation, Physiological:physiology, Adolescent, Anorexia Nervosa:metabolism, Body Mass Index, Child, Female, Humans, Obesity:metabolism, ROC Curve, Resistin:blood, Young Adult,.   

OBJECTIVES: There are only few studies available on blood resistin (RES) levels in patients with anorexia nervosa (AN), which revealed scarce results, however it has been demonstrated that RES mRNA expression in adipose tissue of these patients is increased. The aim of this study is: 1) the evaluation of serum resistin levels in girls with AN and determination a threshold value differentiating these patients from healthy subjects; 2) analysis of the relationship between serum resistin levels and BMI in examined subjects.

DESIGN AND SETTING: Serum RES concentration has been assayed using ELISA kit in 195 adolescent girls: 87 with restrictive AN (mean BMI-SDS: -2.65 ± 0.2), 17 with not otherwise specified eating disorders (NOS) (mean BMI-SDS: -1.4 ± 0.68), 30 with simple obesity (OB) (mean BMI-SDS: 6.91 ± 1.23) and 61 healthy (mean BMI-SDS: -0.18 ± 0.54).

RESULTS: Mean serum RES concentration in AN (2.8 ± 0.6 ng/ml) and NOS (3.1 ± 0.9 ng/ml) were significantly lower (p<0.0001) than in OB and H groups (4.8 ± 0.5 and 4.1 ± 0.4 ng/ml respectively). After corrected for BMI, RES values in AN were similar as in H subjects, but significantly higher (p<0.005) in comparison to OB group. ROC curve analysis revealed that 3.87 ng/ml is the threshold value of RES serum concentration differentiating AN from H girls (specificity 100%, sensitivity 80%). No significant correlations between BMI and serum resistin concentration are found in AN group, although a significant positive correlation has been established for all examined subjects.

CONCLUSION: Additional adaptive mechanisms may be involved in regulation of RES levels in adolescent girls with AN....

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Journal Article 2011; 32(4): 510-517 PubMed PMID: 21876486 Citation  Keywords:  Animal Feed, Animal Nutritional Physiological Phenomena:physiology, Animals, Animals, Suckling:growth & development, Colostrum:metabolism, Dietary Supplements, Esters:pharmacokinetics, Eukaryota, Fatty Acids:pharmacokinetics, Female, Iodine:pharmacokineti.   

OBJECTIVES: The aim of the study was to compare iodine utilization from different sources by sows and their progeny and the levels of T3 and T4 in their serum.

DESIGN: Pregnant Czech Large White × Landrace sows were fed with an experimental KPK diet (a diet for lactating sows) 14 days before parturition until weaning (at a piglet age of 28 days). In group A (n=50, 10 sows, 40 piglets) the feed was supplemented with KI (0.6 mg of iodine per kg of feed). Iodine enriched alga Chlorella spp. (0.6 mg of iodine per kg of feed) was used as a supplement in group B (n=50, 10 sows, 40 piglets). In group C (n=50, 10 sows, 40 piglets) the sows were injected i.m. with IFAE at a dose of 100 mg of iodine per sow. Iodine, T3 and T4 were measured in each group for comparison of iodine utilization.

RESULTS: The use of IFAE resulted in higher serum concentrations in sows compared to KI and alga. In contrast, iodine concentrations in milk and piglets were lower when IFAE were used. We found a wide variation in the concentrations of T3 and T4 in the serum of piglets in all groups.

CONCLUSION: Our results indicate a good utilization of iodized oil by sows. However, its transfer into milk is lower compared to the other iodine sources....

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Journal Article 2010; 31(4): 538-548 PubMed PMID: 20802458 Citation  Keywords:  Analysis of Variance, Animals, Body Weight, Male, Maze Learning:physiology, Noise, Rats, Rats, Wistar, Reversal Learning:physiology, Spatial Behavior:physiology, Stress, Physiological:physiology, Stress, Psychological:physiopathology,.   

OBJECTIVE: This study investigated the cognitive effect of chronic exposure to environmental noise on RAWM performance of juvenile rats, and the ability of adult rats exposed to a novel acute stress to perform in the RAWM as a function of whether or not they were exposed to environmental noise as juveniles.

METHODS: We examined the consequences of exposure to noise during the juvenile-early periadolescent period on adulthood stress response by assessing cognitive performance in the RAWM. Male rats were exposed to environmental noise during the childhood-prepubescent period (21-35 PND), and their RAWM performance was tested at the end of the exposure to noise, and then again two months later when they had to cope with a new stressful event. RAWM execution included a 3-day training phase and a reversal learning phase on day 4. Escape latency, reference memory errors and working memory errors were compared between experimental and control groups. In addition, body weight gain and serum corticosterone levels were evaluated.

RESULTS: Stressed rats demonstrated spatial impairment, as evidenced by poor execution on day 4. This effect was significantly noticeable in the doubly stressed group. Noise annoyance was evidenced by reduced body weight gain and increased serum corticosterone levels.

CONCLUSIONS: Our results suggest that environmental noise may produce potent stress-like effects in developing subjects that can persist into adulthood, affecting spatial learning abilities. This cognitive impairment may restrict the subject's ability to learn under a new spatial configuration....

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Journal Article 2010; 31(1): 19-39 PubMed PMID: 20150886 Citation  Keywords:  Animals, Behavior:physiology, Behavior Therapy:methods, Diet Therapy:psychology, Exercise:physiology, Exercise Therapy:methods, Humans, Models, Biological, Neurobiology, Nutritional Physiological Phenomena:physiology, Relaxation Therapy:psychology, Stress.   

BACKGROUND AND OBJECTIVE: Stress is natural and belongs to life itself. To sustain it and even grow with it biology invented different mechanisms, since stress resistance is obligatory. These pathways, we surmise, can be activated and learned intentionally, through professional stress management training or 'mind-body medicine', or endogenously and automatically through autoregulation. Since the primary goal of various stress-reducing approaches is corresponding, we expect to find an overlapping physiology and neurobiological principle of stress reduction. These common pathways, as we speculate, involve some of the very same signalling molecules and structures.

METHODS: Concepts of stress and stress management are described and then associated with underlying molecular and neurobiological pathways. Evidence is gathered from different sources to substantiate the hypothesis of an overlapping neurobiological principle in stress autoregulation.

RESULTS: Stress describes the capacity and mechanisms to sustain and adjust to externally or internally challenging situations. Therefore, organisms can rely on the endogenous ability to self-regulate stress and stressors, i.e., autoregulatory stress management. Stress management usually consists of one to all of the following instruments and activities: behavioral or cognitive, exercise, relaxation and nutritional or food interventions (BERN), including social support and spirituality. These columns can be analyzed for their underlying neurobiological and autoregulatory pathways, thereby revealing a close connection to the brain's pleasure, reward and motivation circuits that are particularly bound to limbic structures and to endogenous dopamine, morphine, and nitric oxide (NO) signalling. Within this work, we demonstrate the existence of opioid, opiate, dopamine and related pathways for each of the selected stress management columns.

DISCUSSION: Stress management techniques may possess specific and distinct physiological effects. However, beneficial behaviors and strategies to overcome stress are, as a more general principle, neurobiologically rewarded by pleasure induction, yet positively and physiologically amplified and reinforced, and this seems to work via dopamine, endorphin and morphine release, apart from other messenger molecules. These latter effects are unspecific, however, down-regulatory and clearly stress-reducing by their nature.

CONCLUSIONS: There seems to exist a common neurobiological mechanism, i.e., limbic autoregulation, that involves dopamine, morphine and other endogenous signalling molecules, e.g., other opioid receptor agonists, endocannabinoids, oxytocin or serotonin, many of which act via NO release, and this share seems to be of critical importance for the self-regulation and management of stress: stress management is an endogenous potential....

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