An Assessment of Serum Selenium Concentration in Women with Ovarian Cancer.

BACKGROUND: Available studies on the effect of serum selenium levels on the risk of malignancies show some conflicting results. In this study, we investigated the correlation between serum selenium levels and ovarian cancer occurrence. METHODS: 314 women (157 diseased patients and 157 healthy ones) matched in terms of age and BMI were included in the study. The measurements of selenium in the collected blood samples were performed using an ICP mass spectrometer. Univariable and multivariable analyzes were performed to determine the relationship between the factors under the study and the occurrence of ovarian cancer. RESULTS: The mean concentration of selenium was lower among diseased ones than among controls (53.31 µg/L vs. 78.99 µg/L). A decrease in selenium concentration was noticed with the advancement of ovarian cancer. In univariable and multivariable analyzes, a clear relationship between low selenium concentration and the occurrence of ovarian cancer was found (35.3 (95% CI: 11.2-111; p < 0.001) and 45.8 (95% CI: 12.8-164; p < 0.001)). CONCLUSION: The studied patients with ovarian cancer are characterized by statistically significant lower serum selenium levels than patients from the control group. Among the study group, a decrease in selenium concentration was observed with an increase in the FIGO stage. The determination of the role of selenium as a prophylactic factor in ovarian cancer requires further prospective studies.

Femistina versus Canephron as a prevention of urinary tract infections after midurethral sling surgery - Non-inferiority study.

OBJECTIVE: Urinary tract infection (UTI) is relatively common post-operative complication following midurethral sling placement (MUS), even in cases where intraoperative antibiotic prophylaxis was given. The primary aim of this study was to investigate the non-inferiority of Femistina as compared with Canephron in reducing symptomatic UTI in first six months following surgery. STUDY DESIGN: A sample size of 144 patients per group was established, to provide at least 90% power to demonstrate the non-inferiority of phytodrug Femistina versus Canephron as a prevention of post-MUS urinary tract infection. RESULTS: Women suffering from stress urinary incontinence and mixed urinary incontinence (MUI) with predominant SUI symptoms as confirmed by urodymamics (n = 320) were randomized in a 1:1 ratio to Femistina (40 mg, oral, twice daily for 20 days) or Canephron (3 × 5 ml taken orally-three times daily for 4 weeks). Both groups were homogenous for age, type of operation (only TOT outside-in) and severity of illness as indicated by ICIQ-SF questionnaire. We found that symptoms of UTI were significantly lower in patients receiving Femistina. During first 6 months after surgery UTI was confirmed in only 10 patients receiving Femistina (6,25%) when compared to 25 (15,63%) subjects receiving Canephron, p < 0.007. CONCLUSION: Femistina is not inferior to Canephron in preventing lower urinary tract infection after midurethral sling surgery.

New Kid on the Block: The Efficacy of Phytomedicine Extracts Urox® in Reducing Overactive Bladder Symptoms in Rats.

The aim of the current study was to determine if phytomedicine (Urox®) would reverse retinyl acetate (RA)-induced changes characteristic of bladder overactivity. There were 60 rats divided into the following 4 groups: I-control, II-received RA to induce detrusor overactivity (DO), III-received Urox (840 mg daily for 14 days), and IV-received combination of RA and Urox®. The cystometry was performed 2 days after the last dose of Urox®. Next, urothelium thickness and biochemical parameter measurements were performed. In group IV, a decrease in basal pressure and detrusor overactivity index was noted when compared to group II. Furthermore, in group IV the following parameters were increased: threshold pressure, voided volume, intercontraction interval, and bladder compliance in comparison with group II. There were significant elevations in c-Fos expression in the neuronal voiding centers in group II, while the expression of c-Fos in group IV was normalized. No significant changes in the values of the analyzed biomarkers in group III were found, while in group II, an elevation in BDNF, NGF, CGRP, ATP, Rho kinase, malondialdehyde, 3-nitrotyrosine, TRPV1, OCT-3, and VAChT and then a decrease in E-cadherin and Z01 were found. A successful restoration of all the abovementioned biomarkers' levels was observed in group IV. Phytomedicine extracts (Urox®) were found to be potent in reversing RA-induced changes in several cystometric and biochemical parameters that are determinants of overactive bladder (OAB). The actions of Urox® were proved to be dependent on several factors, such as growth factors and several OAB biomarkers but not pro-inflammatory cytokines.

An Assessment of Serum Selenium Concentration in Women with Endometrial Cancer.

Background: Numerous studies have shown a relationship between low serum selenium levels and an increased risk of developing cancer. Methods: A total of 306 women participated in the study: 153 patients diagnosed with endometrial cancer and 153 healthy women who were matched, in terms of birth year (+/−3 years), to the patients from the study group. The quantitative measurement of selenium content in the collected blood samples was performed using a mass spectrometer with excitation in inductively coupled plasma. In order to determine the relationship between the risk factors and the incidence of endometrial cancer, analyses based on single- and multi-factor conditional logistic regression models were performed. Results: The mean concentration of selenium was lower in patients with endometrial cancer than in healthy controls (60.63 µg/L (0.77 µmol/L) vs. 78.74 µg/L (0.99 µmol/L), respectively). When compared in quartiles, a significant association of lower selenium concentration with the incidence of endometrial cancer was recorded. The highest OR was observed in the first and second quartiles (OR-22.0, p-value < 0.001; medium selenium level 46.95 µg/L (0.59 µmol/L), and OR-5.94; p-value < 0.001; medium selenium level 63.60 µg/L (0.80 µmol/L), respectively). Conclusion: A strong correlation between the level of selenium in the blood serum and the risk of endometrial cancer indicates that patients with low levels should be a candidate group requiring appropriate preventive examinations. Further research on a larger group of patients is required.

The influence of Potentilla chinensis aqueous extract on urinary bladder function in retinyl acetate-induced detrusor overactivity in rats.

INTRODUCTION & OBJECTIVES: In overactive bladder (OAB) therapy several herbal medicines presented promising effects, however the results are sparse to provide their efficacy. Herbals may become a popular alternative for OAB therapy. Therefore, we investigated whether Potentilla chinensis extract (PCE) would reverse retinyl acetate (RA)-induced detrusor overactivity (DO). MATERIAL & METHODS: 60 rats were divided into 4 groups, as follows: I - control, II - rats with RA-induced DO, III - rats received PCE in dose of 500 mg/kg, and IV - rats with RA-induced DO which received PCE. PCE or vehicle were administered orally for 14 days. The cystometry and bladder blood flow assessment were performed 3 days after the last dose of the PCE. Then the rats were put into the metabolic cages for 24 h. Next, urothelium thickness measurement and biochemical analyses were performed. < /p>

Results. Intravesical infusion of RA solution induced DO. PCE had no influence on the urinary bladder function and  micturition cycles in normal rats. PCE diminished the severity of RA-induced DO. In the urothelium the RA induced the elevation of ATP, CGRP, substance P, VEGF-A, OTC3, and ERK1/2. The concentration of NOS2, CDH1, and ZO1 decreased. Moreover, RA affected the concentration of SNARE proteins (increased concentration of SNAP23, SNAP25, and SV2A). Also in detrusor the elevated level of ROCK1 and VAChT were observed. In turn, PCE in RA-induced DO caused a reversal of the described biochemical changes within urothelium, detrusor muscle and urine. < /p>

Conclusions. PCE attenuates detrusor overactivity. The potential mechanisms of action of PCE in the urinary bladder seem to be multifactorial and complex. PCE seems to become a reasonable novel OAB therapy.

Spectral analysis versus signal complexity methods for assessing attention related activity in human EEG.

We aimed to find the most effective analytical method for assessment of attention related activity to be used in neurofeedback training. We compared commonly used spectral EEG methods with those measuring signal complexity - based on calculation of entropy and fractal dimension. The 14 subjects were examined with a modified delayed matching-to-sample task. All investigated methods revealed significant differences of EEG signals recorded in control and attentional trials, however the selection of signals with such differences varied between subjects and applied methods. The results indicated: (i) the importance of the individual analysis of signals from each subject and session, (ii) benefits of applying signal complexity methods to support spectral analysis in a further application and (iii) an advantage of the signal complexity method, carrying information of assembles of spectral components, over common spectral methods.

Cannabinoids in depressive disorders.

Cannabis sativa is one of the most popular recreational and medicinal plants. Benefits from use of cannabinoid agents in epilepsy, multiple sclerosis, Parkinson's disease, Alzheimer's disease, and others have been suggested. It seems that the endocannabinoid system is also involved in the pathogenesis and treatment of depression, though its role in this mental disease has not been fully understood yet. Both the pro- and antidepressant activity have been reported after cannabis consumption and a number of pre-clinical studies have demonstrated that both agonist and antagonist of the endocannabinoid receptors act similarly to antidepressants. Responses to the cannabinoid agents are relatively fast, and most probably, the noradrenergic, serotoninergic, glutamatergic neurotransmission, neuroprotective activity, as well as modulation of the hypothalamic-pituitary-adrenal axis are implicated in the observed effects. Based on the published data, the endocannabinoid system evidently gives novel ideas and options in the field of antidepressant treatment, however further studies are needed to determine which group of patients could benefit from this type of therapy.

CB1 cannabinoid receptor ligands augment the antidepressant-like activity of biometals (magnesium and zinc) in the behavioural tests.

OBJECTIVE: During the last few decades, endocannabinoid system has emerged as a novel possible target for antidepressant treatment. Although the medical literature provides information on the mood-changing effects of CB1 ligands, little is known about the possible interaction between the simultaneous activation or inhibition of the CB1 receptor and administration of other agents that possess antidepressant potential. The main goal of our study was to evaluate the influence of the CB1 cannabinoid receptor ligands (oleamide - an endogenous agonist and AM251 - an inverse agonist/antagonist) on the antidepressant-like activity of biometals (i.e. magnesium and zinc). METHODS: The forced swim test and the tail suspension test in mice were used to determine the antidepressant-like activity. KEY FINDINGS: Concomitant intraperitoneal administration of per se inactive doses of oleamide (5 mg/kg) or AM251 (0.25 mg/kg) and the tested biometals (i.e. magnesium, 10 mg/kg or zinc, 5 mg/kg) shortened the immobility time of animals in the forced swim test and the tail suspension test. The observed effect was not associated with an increase in spontaneous locomotor activity of mice. CONCLUSIONS: The simultaneous modulation of the cannabinoid system and supplementation of magnesium or zinc produce at least additive antidepressant-like effect.

EEG-neurofeedback training of beta band (12-22Hz) affects alpha and beta frequencies - A controlled study of a healthy population.

The frequency-function relation of various EEG bands has inspired EEG-neurofeedback procedures intending to improve cognitive abilities in numerous clinical groups. In this study, we administered EEG-neurofeedback (EEG-NFB) to a healthy population to determine the efficacy of this procedure. We evaluated feedback manipulation in the beta band (12-22Hz), known to be involved in visual attention processing. Two groups of healthy adults were trained to either up- or down-regulate beta band activity, thus providing mutual control. Up-regulation training induced increases in beta and alpha band (8-12Hz) amplitudes during the first three sessions. Group-independent increases in the activity of both bands were observed in the later phase of training. EEG changes were not matched by measured behavioural indices of attention. Parallel changes in the two bands challenge the idea of frequency-specific EEG-NFB protocols and suggest their interdependence. Our study exposes the possibility (i) that the alpha band is more prone to manipulation, and (ii) that changes in the bands' amplitudes are independent from specified training. We therefore encourage a more comprehensive approach to EEG-neurofeedback training embracing physiological and/or operational relations among various EEG bands.

SN003, a CRF1 receptor antagonist, attenuates depressive-like behavior and detrusor overactivity symptoms induced by 13-cis-retinoic acid in rats.

Overactive bladder (OAB) often co-exists with depression in women. The corticotropin-releasing factor (CRF) system participates in the pathophysiology of both disorders. Therefore, we tested the effects of acute treatment with a reversible CRF receptor type-1 (CRF1) antagonist, SN003 (1mg/kg, i.v.), representatives of first (solifenacin, 0.03mg/kg, i.v.) and second (mirabegron, 1mg/kg, i.v.) line treatments for OAB as well as an antidepressant imipramine (30mg/kg, i.p.) on changes in depressive-like behavior and detrusor overactivity (DO) symptoms induced by a 6-week administration of 13-cis-retinoic acid (13-cis-RA, 1mg/kg/day, i.p.) in female Wistar rats, using in vivo cystometric investigations, forced swim test (FST) and spontaneous locomotor activity test. Following cystometric and behavioral studies, tissue was harvested and CRF level was assessed in the hypothalamus, amygdala and plasma. 13-cis-RA-induced depressive-like behavior and DO symptoms were associated with increased CRF levels in the hypothalamus, amygdala and plasma. Solifenacin and mirabegron attenuated DO symptoms induced by 13-cis-RA, did not display antidepressant-like activity and did not influence CRF levels in brain tissues or plasma. Imipramine and SN003 displayed antidepressant-like activity and lowered increased levels of CRF in brain tissues and plasma. Imipramine attenuated changes in some of the cystometric parameters, which are associated with OAB dry (without urge incontinence), whereas SN003 attenuated changes in almost all cystometric parameters that were induced by 13-cis-RA. CRF1 antagonist may be beneficial in case of OAB wet (with urge incontinence) or dry co-existing with depression. The possible mechanism may be related to the effects on central/peripheral CRF system.

Inhibition of the CRF1 receptor influences the activity of antidepressant drugs in the forced swim test in rats.

Hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA) and impairment of the central corticotropin-releasing factor (CRF) system are factors in the pathogenesis of depression. Though several antagonists of the CRF1 receptor were effective in the recognized behavioral tests for antidepressant activity, there is still little information on the potential interactions between CRF1 receptor inhibitors and conventional antidepressant therapy. The aim of our study was to assess the influence of SN003, a CRF1 receptor blocker, on the activity of imipramine and fluoxetine in the forced swim test (FST) in rats which presented some signs of depression. The experiments were carried out on female Wistar rats subjected to 14-day subcutaneous corticosterone (CORT) administration (20 mg/kg/day). The antidepressant-like effect was determined by the FST and the CRF levels in the hypothalamus, amygdala, and peripheral blood were measured by a high-sensitivity immunoenzymatic test. SN003 (0.5 mg/kg) potentiated the antidepressant-like effect of imipramine (15 mg/kg) and fluoxetine (7.5 mg/kg). Moreover, the co-administration of the tested agents abolished CORT-induced increase in CRF levels in the examined biological material more profoundly than monotherapy. Our present findings give further evidence that the blockage of CRF action may be useful in the treatment of mood disorders. The concurrent use of well-known antidepressants with CRF1 receptor antagonists could be beneficial in terms of safety, since it requires lower doses of the applied agents.

The influence of caffeine on the activity of moclobemide, venlafaxine, bupropion and milnacipran in the forced swim test in mice.

AIMS: Worrying data indicate that excessive caffeine intake applies to patients suffering from mental disorders, including depression. It is thus possible to demonstrate the usefulness of caffeine and its derivatives in the treatment of depression. The main goal of the present studywas to evaluate the influence of caffeine (5mg/kg) on the activity of moclobemide (1.5 mg/kg), venlafaxine (1 mg/kg), bupropion (10 mg/kg), and milnacipran (1.25 mg/kg). Moreover, we assessed the influence of caffeine on their serum and brain levels using highperformance liquid chromatography. MAIN METHODS: The experiment was carried out on naïve adult male Albino Swiss mice. Caffeine and tested drugs were administered intraperitoneally. The influence of caffeine on the activity of selected antidepressant drugs was evaluated in forced swim test (FST). Locomotor activity was estimated to verify and exclude false positive/negative results. To assess the influence of caffeine on the levels of studied antidepressant drugs, their concentrations were determined in murine serum and brains using high-performance liquid chromatography. KEY FINDINGS: Caffeine potentiated activity of all antidepressants examined in FST and the observed effects were not due to the increase in locomotor activity in the animals. Only in the case of co-administration of caffeine and milnacipran an increased milnacipran concentration in serum was observed without affecting its concentration in the brain. SIGNIFICANCE: Caffeine potentiates the activity of antidepressant drugs from different chemical groups. The interactions of caffeine with venlafaxine, bupropion and moclobemide occur in pharmacodynamic phase, whereas the interaction of caffeine­milnacipran occurs, at least partially, in pharmacokinetic phase.

Brain-training for physical performance: a study of EEG-neurofeedback and alpha relaxation training in athletes.

In recent years, EEG-neurofeedback training (EEG-NFB) has been increasingly used to optimize various brain functions. Better performance in various activities was also reported after relaxation trainings, another popular method in therapeutic practice. Both these methods are used as a part of professional coaching in sports training centers. In the present study, we aimed to evaluate the impact of such holistic training on physiological (EEG) and behavioral measures on semi-professional athletes. EEG-NFB paradigm was intended for amplification of the amplitudes of SMR (12-15 Hz) and beta1 (13-20 Hz) bands and simultaneous reduction of the amplitude of theta (4-7.5 Hz) and beta2 (20-30 Hz). Participation in NFB sessions was accompanied with self-administration of relaxing, audio-visual stimulation after each daily athletic training session. The training program resulted in the increase of alpha and beta1 power of trained participants when assessed in rest with eyes-closed. In eyes - open state, participants of the trained group maintained the same level in all frequency bands, in opposite to the control subjects, whose power decreased in the second measurement in beta1 band when compared to the first one. The trained group exhibited greater reduction of reaction times in a test of visual attention than the control group and showed improvement in several performance measures of Kraepelin's work-curve, used to evaluate speed, effectiveness and work accuracy. Together, these results present initial support for the use of holistic, neurophysiological training in sports workout.

A novel in-vitro model of human aortic valve mineralization.

BACKGROUND AND AIM OF THE STUDY: The study aim was to develop an in-vitro model of human aortic valve homograft (AVH) mineralization, as a basis for further research on the subject of calcific aortic valve disease (CAVD). METHODS: Human aortic valves were excised during autopsy (12-24 h post-mortem) from donors who had died due to accident or suicide. The mean (±SD) donor age was 32.5 ± 11.4 years. Under sterile conditions each aortic cusp (three cusps per valve) was cut in half to provide a total of 240 tissue samples. AVH mineralization was assessed in solutions with different Ca and P concentrations and CaxPO4 ionic product values. The impact of time on aortic valve mineralization rate was assessed using energy-dispersive X-ray fluorescence (ED-XRF). RESULTS: The model showed that human AVH mineralization can be best observed in a solution with a CaxPO4 ionic product of 2.2 mmol2/l2. The optimum incubation time for observing AVH mineralization was 21 days. CONCLUSION: A novel in-vitro AVH mineralization model was developed for use in future studies.

Impact of meditation on emotional processing--a visual ERP study.

Impact of meditation on emotional processing, and its clinical applications, has recently drawn significant interest. In this visual event-related potential (ERP) study we investigated whether long-term meditation practitioners exhibit different ERP responses to the emotional load of stimuli (IAPS pictures) than control subjects with no experience in meditation. Differences were observed in the late positive potential (LPP). LPP amplitude is typically greater in ERPs evoked by emotionally arousing scenes, specifically negative images, compared to neutral scenes. This effect was also replicated in our study, but not in case of meditators' frontal scalp regions, who differed significantly in this respect from control subjects. Our findings provide support for different emotional processing in meditation practitioners: at high levels of processing meditators are less affected by stimuli with adverse emotional load, while processing of positive stimuli remains unaltered. To further confirm this observation, a long-term longitudinal random assignment study would be desirable.

Cross-trial correlation analysis of evoked potentials reveals arousal-related attenuation of thalamo-cortical coupling.

We describe a computational method for assessing functional connectivity in sensory neuronal networks. The method, which we term cross-trial correlation, can be applied to signals representing local field potentials (LFPs) evoked by sensory stimulations and utilizes their trial-to-trial variability. A set of single trial samples of a given post-stimulus latency from consecutive evoked potentials (EPs) recorded at a given site is correlated with such sets for all other latencies and recording sites. The results of this computation reveal how neuronal activities at various sites and latencies correspond to activation of other sites at other latencies. The method was used to investigate the functional connectivity of thalamo-cortical network of somatosensory system in behaving rats at two levels of alertness: habituated and aroused. We analyzed potentials evoked by vibrissal deflections recorded simultaneously from the ventrobasal thalamus and barrel cortex. The cross-trial correlation analysis applied to the early post-stimulus period (<25 ms) showed that the magnitude of the population spike recorded in the thalamus at 5 ms post-stimulus correlated with the cortical activation at 6-13 ms post-stimulus. This correlation value was reduced at 6-9 ms, i.e. at early postsynaptic cortical response, with increased level of the animals' arousal. Similarly, the aroused state diminished positive thalamo-cortical correlation for subsequent early EP waves, whereas the efficacy of an indirect cortico-fugal inhibition (over 15 ms) did not change significantly. Thus we were able to characterize the state related changes of functional connections within the thalamo-cortical network of behaving animals.

Extracting functional components of neural dynamics with Independent Component Analysis and inverse Current Source Density.

Local field potentials have good temporal resolution but are blurred due to the slow spatial decay of the electric field. For simultaneous recordings on regular grids one can reconstruct efficiently the current sources (CSD) using the inverse Current Source Density method (iCSD). It is possible to decompose the resultant spatiotemporal information about the current dynamics into functional components using Independent Component Analysis (ICA). We show on test data modeling recordings of evoked potentials on a grid of 4 × 5 × 7 points that meaningful results are obtained with spatial ICA decomposition of reconstructed CSD. The components obtained through decomposition of CSD are better defined and allow easier physiological interpretation than the results of similar analysis of corresponding evoked potentials in the thalamus. We show that spatiotemporal ICA decompositions can perform better for certain types of sources but it does not seem to be the case for the experimental data studied. Having found the appropriate approach to decomposing neural dynamics into functional components we use the technique to study the somatosensory evoked potentials recorded on a grid spanning a large part of the forebrain. We discuss two example components associated with the first waves of activation of the somatosensory thalamus. We show that the proposed method brings up new, more detailed information on the time and spatial location of specific activity conveyed through various parts of the somatosensory thalamus in the rat.

Fresh-wet storage accelerates aortic homograft calcification.

The studies were focused on the influence of the fresh-wet storage procedure on aortic valve homograft (AVH) mineralization. Thirty-four aortic valves excised at autopsy were investigated. The cusps were divided into halves, the first one was used as a control while the second half was stored in Morgan, Morton, and Parker's Medium 199 supplemented with an antibiotic mixture at 4 degrees C for 28 days. The elemental compositions of the samples were determined by the energy dispersive X-ray fluorescence method. The Ca/P ratio and Ca concentration was used as markers of the mineralization development. It was found that the AVH mineralization was accelerated by the applied fresh-wet storage procedure. The aggravation of the AVH mineralization was correlated with the Ca content before storage especially in case of old donors. For donors older than 40 years an increase of Ca concentrations by approximately 40% was observed. To limit AVH mineralization due to fresh-wet storage, age of donors should not exceed approximately 40 years. Another method to reduce AVH mineralization relies on a modification of the medium commonly applied in the fresh-wet storage procedure, and research are ongoing.

Influence of zinc supplementation on imipramine effect in a chronic unpredictable stress (CUS) model in rats.

Zinc is an endogenous modulator of neuronal activity and may play an important role in the pathogenesis of depression. Recent studies have shown that zinc exhibits antidepressant-like activity in some models of depression in rodents. Our previous studies have shown that the footshock-induced fighting behavior was reduced in the rats subjected to chronic unpredictable stress (CUS). This test is used as the new experimental model of depression. Various antidepressant drugs given repeatedly prevented this kind of behavioral depression. The aim of the present study was to evaluate the effect of prolonged treatment with zinc hydroaspartate and to examine if zinc supplementation could modulate the imipramine effect in CUS model of behavioral depression in rats. The experiments were carried out on male Wistar rats. Chronic stress (persisting for 16 days) was induced by the modified method described by Katz et al. Zinc hydroaspartate at the dose of 30 mg/kg/day or 15 mg/kg/day and imipramine at the dose of 5 mg/kg/day were administered once daily for 14 days. Imipramine was given (ip) 1 h before every stress session and zinc hydroaspartate (ip) l h before the antidepressant. The footshock-induced fighting behavior test was performed 48 h after the last session of the chronic stress. It was demonstrated that in chronically stressed rats the number of fighting attacks was significantly reduced (by about 75%). Zinc hydroaspartate at the dose of 30 mg/kg/day, given alone, prevented the deficit in fighting behavior in chronically stressed rats. Neither imipramine at the dose of 5 mg/kg/day nor zinc hydroaspartate (15 mg/kg/day) administered alone changed the intensity of fighting behavior in chronically stressed rats. However, when imipramine was given at the same dose in the rats pretreated with zinc hydroaspartate (15 mg/kg/day) the deficit of fighting behavior was not observed. The present results indicate that zinc similarly to antidepressants protects the rats against the CUS-induced behavioral depression. Moreover, our findings suggest that zinc supplementation could potentiate the antidepressant effect of imipramine.

Attention-dependent coupling between beta activities recorded in the cat's thalamic and cortical representations of the central visual field.

We have previously proposed that enhanced 16-24 Hz (beta) local field potential activity in the primary visual cortex and lateral geniculate nucleus may be an electrophysiological correlate of the attentional mechanism that increases the gain of afferent visual information flow to the cortex. In this study, we measured coupling between beta signals recorded in the thalamic (i.e. lateral geniculate or perigeniculate) and cortical representations of the central visual field (within 5 degrees from area centralis), during visual and auditory attentive situations. Signal coupling was calculated in two ways: (i) by means of crosscorrelation between raw beta activities, which depends primarily on phase coherence, and (ii) by phase-independent crosscorrelation between amplitude envelopes of beta activities. Mean amplitudes of raw signal cross correlations obtained for thalamo-cortical recording pairs were not significantly different when calculated during behavioural demands for either visual or auditory attention. In contrast, amplitudes of envelope cross correlations obtained during behaviour requiring visual attention were, on average, two times higher than those calculated during the auditory task. This attention-related coupling emerged from synchronized amplitude modulation of beta oscillatory activity that occurs within the cortico-thalamic circuit involved in central vision.