Open field test for the assessment of anxiety-like behavior in Gnathonemus petersii fish

The open field test (OFT) is a basic and most widely used test for investigation in animal studies of the neurobiological basis of anxiety and screening for novel drug targets. Here, we present the results of an OFT for weakly electric fish Gnathonemus petersii. This study aimed to describe the behavioral response of G. petersii exposed to an OFT, simultaneously with an evaluation of electrical organ discharges (EOD), to determine whether any association between EOD and patterns of motor behavior in the OFT exists. Treatment of OFT activity and its temporal patterning was assessed for the whole 6-min trial as well as per-minute distributions of activity using a near-infrared camera and an EOD data acquisition system. Our results demonstrated that the time spent, distance moved, and time of activity were significantly higher in the periphery of the OFT arena. The zone preference pattern over the 6-min test session showed that G. petersii prefer the outer zone (83.61%) over the center of the arena (16.39%). The motor behavior of fish measured as distance moved, active time, and swim speed were correlated with the number of EODs; however, no relationship was found between EOD and acceleration.

Chemobrain in blood cancers: How chemotherapeutics interfere with the brain's structure and functionality, immune system, and metabolic functions

Cancer treatment brings about a phenomenon not fully clarified yet, termed chemobrain. Its strong negative impact on patients' well-being makes it a trending topic in current research, interconnecting many disciplines from clinical oncology to neuroscience. Clinical and animal studies have often reported elevated concentrations of proinflammatory cytokines in various types of blood cancers. This inflammatory burst could be the background for chemotherapy-induced cognitive deficit in patients with blood cancers. Cancer environment is a dynamic interacting system. The review puts into close relationship the inflammatory dysbalance and oxidative/nitrosative stress with disruption of the blood-brain barrier (BBB). The BBB breakdown leads to neuroinflammation, followed by neurotoxicity and neurodegeneration. High levels of intracellular reactive oxygen species (ROS) induce the progression of cancer resulting in increased mutagenesis, conversion of protooncogenes to oncogenes, and inactivation of tumor suppression genes to trigger cancer cell growth. These cell alterations may change brain functionality, as well as morphology. Multidrug chemotherapy is not without consequences to healthy tissue and could even be toxic. Specific treatment impacts brain function and morphology, functions of the immune system, and metabolism in a unique mixture. In general, a chemo-drug's effects on cognition in cancer are not direct and/or in-direct, usually a combination of effects is more probable. Last but not least, chemotherapy strongly impacts the immune system and could contribute to BBB disruption. This review points out inflammation as a possible mechanism of brain damage during blood cancers and discusses chemotherapy-induced cognitive impairment.

Ketamine disrupts locomotion and electrolocation in a novel model of schizophrenia, Gnathonemus petersii fish

The present study aimed to examine a weakly electric fish Gnathonemus petersii (G. petersii) as a candidate model organism of glutamatergic theory of schizophrenia. The idea of G. petersii elevating the modeling of schizophrenia symptoms is based on the fish's electrolocation and electrocommunication abilities. Fish were exposed to the NMDA antagonist ketamine in two distinct series differing in the dose of ketamine. The main finding revealed ketamine-induced disruption of the relationship between electric signaling and behavior indicating impairment of fish navigation. Moreover, lower doses of ketamine significantly increased locomotion and erratic movement and higher doses of ketamine reduced the number of electric organ discharges indicating successful induction of positive schizophrenia-like symptoms and disruption of fish navigation. Additionally, a low dose of haloperidol was used to test the normalization of the positive symptoms to suggest a predictive validity of the model. However, although successfully induced, positive symptoms were not normalized using the low dose of haloperidol; hence, more doses of the typical antipsychotic haloperidol and probably also of a representative of atypical antipsychotic drugs need to be examined to confirm the predictive validity of the model.

Several reasons why ketamine as a neuroplastic agent may have failed to prevent postoperative delirium: Implications for future protocols

Ketamine exerts anti-inflammatory, neuroprotective and neuroplastic activity, therefore it may counteract the neurotoxic processes underlying postoperative delirium. However, the majority of studies in this field failed. We identified several pharmacological reasons why these studies may have failed, together with suggestions of how to remediate them. Among them, the interaction with intravenous general anesthetics exerting the opposite effect on GABA interneurons than ketamine may be of principal importance. We suggest biomarkers which may elucidate the influence of this interaction on the different steps of neuroplastic pathways. We hypothesize that administering ketamine before or after general anesthesia could both prevent the interactions and strengthen the effect of ketamine by timing surgery within the climax of ketamine-induced neuroplastic changes or by stabilizing AMPA receptors. It is vital to deal with these questions because the protocols of ongoing studies are based again on the administration of ketamine during general anesthesia (the major identified pitfall).

The effect of low-frequency rTMS on auditory hallucinations, EEG source localization and functional connectivity in schizophrenia

BACKGROUND

Low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) diminishes auditory hallucinations (AHs). The aims of our study were a) to assess the efficacy of LF-rTMS in a randomized, sham-controlled double-blind alignment, b) to identify the electrophysiological changes accompanying the LF-rTMS, and c) to identify the influence of LF-rTMS on brain functional connectivity (FC).

METHODS

Nineteen schizophrenia patients with antipsychotic-resistant AHs were randomized to either active (n = 10) or sham (n = 9) LF-rTMS administered over the left temporo-parietal region for ten days. The clinical effect was assessed by the Auditory Hallucination Rating Scale (AHRS). The localization of the differences in electrical activity was identified by standardized low resolution brain electromagnetic tomography (sLORETA) and FC was measured by lagged phase synchronization.

RESULTS

AHRS scores were significantly improved for patients receiving active rTMS compared to the sham (median reduction: 40 % vs 12 %; p = 0.01). sLORETA revealed a decrease of alpha-2, beta-1,-2 bands in the left hemisphere in the active group. Active rTMS led to a decrease of the lagged phase connectivity in beta bands originating in areas close to the site of stimulation, and to a prevailing increase of alpha-2 FC. No significant differences in current density or FC were observed in the sham group.

LIMITATIONS

Limitations to our study included the small group sizes, and the disability of LORETA to assess subcortical neuronal activity.

CONCLUSIONS

LF-rTMS attenuated AHs and induced a decrease of higher frequency bands on the left hemisphere. The FC changes support the assumption that LF-rTMS is linked to the modulation of cortico-cortical coupling.

Histopathological Findings of Lung Cancer in Black Coal Miners in the Czech Republic

Background

Coal miners with coal workers’ pneumoconiosis (CWP, J60 according to ICD-10) were previously found to have a significantly higher risk of lung carcinoma compared to the general male population. The presented study aimed to analyze the incidence of lung carcinoma in miners, histopathological findings in cohorts with and without CWP, and effect of smoking cessation on the histopathological profile.

Methods

Analysed cohorts consisted of miners with (n = 3476) and without (n = 6687) CWP. Data on personal and working history obtained from the medical records were combined with information on lung cancer from the Czech Oncological Register and histopathological findings. Statistical analysis was performed using non-parametric tests and the incidence risk ratio (significance level of 5%).

Results

In 1992-2015, 180 miners (2.7%) without CWP and 169 (4.9%) with CWP, respectively, were diagnosed with lung carcinoma. The risk of lung cancer in miners with CWP was 1.82 (95% CI: 1.48-2.25) times higher than in those without CWP. Squamous cell carcinoma (37%) was the most common histopathological type, followed by adenocarcinoma (22%) and small cell carcinoma (21%). A statistically significant difference between the cohorts (p = 0.003) was found in the histopathological subtypes, with the incidence of small cell carcinoma being 2 times higher in miners without CWP than in those with CWP. Only a few individuals with lung carcinoma were non-smokers. The incidence of small cell carcinoma, which is strongly associated with smoking, is significantly higher in miners without CWP.

Conclusions

Smoking constitutes the most important risk factor for developing lung carcinoma even in that cohort. However, CWP remains a very important risk factor.

This work was supported by grant of Research Support Foundation, Vaduz. Markus R. Tödtli Consulting and project Healthy Aging in the Industrial Environment CZ.02.1.01/0.0/0.0/16_019/0000798 (HAIE).

Key messages

Novel concept suppressing plasma heat pulses in a tokamak by fast divertor sweeping

One of the remaining challenges in magnetic thermonuclear fusion is survival of the heat shield protecting the tokamak reactor vessel against excessive plasma heat fluxes. Unmitigated high confinement edge localized mode (ELM) is a regular heat pulse damaging the heat shield. We suggest a novel concept of magnetic sweeping of the plasma contact strike point fast and far enough in order to spread this heat pulse. We demonstrate feasibility of a dedicated copper coil in a resonant circuit, including the induced currents and power electronics. We predict the DEMO ELM properties, simulate heat conduction, 3D particles motion and magnetic fields of the plasma and coil in COMSOL Multiphysics and Matlab. The dominant system parameter is voltage, feasible 18 kV yields 1 kHz sweeping frequency, suppressing the ELM-induced surface temperature rise by a factor of 3. Multiplied by other known mitigation concepts, ELMs might be mitigated enough to ensure safe operation of DEMO.

Suicide attempts as a cause of pelvic injuries during the COVID-19 pandemic

OBJECTIVES

We decided to compare the incidence and spectrum of pelvic fractures in 2020 affected by the anti-pandemic measures due to COVID-19 with previous years 2018 and 2019.

METHODS

This retrospective study included 391 patients treated at the author's clinic for pelvic fractures. From the medical records we recorded gender, age, mechanism of injury, trauma energy, fracture type based on the AO classification and severity of injury.

RESULTS

As expected, we observed no difference in the number of fractures caused by simple falls. However, we failed to prove a reduction in the number of high-energy injuries. In contrary, we observed an increase in the number of high-energy injuries in the period between lockdowns (p=0.0375). A surprising result was a dramatic increase in suicide attempts as a cause of pelvic fractures, with 6 (2.2 %) in 2018 and 2019 compared to 13 (10 %) in 2020 alone (p=0.0017).

CONCLUSION

We observed the increased number of suicidal attempts only on a limited number of specific patients with pelvic fractures; therefore, we cannot formulate any general conclusions regarding the incidence of suicide during the COVID-19 pandemic. Nevertheless, we consider this to be a warning signal highlighting the worsened population mental health due to COVID-19 pandemic (Tab. 2, Fig. 1, Ref. 34).

Effect of Lactic Fermentation and Cooking on Nutrient and Mineral Digestibility of Peas

Peas are prospectively beneficial legumes in the human diet, and especially in a vegan and vegetarian diet, due to their high content of proteins and starch. Their frequent lack of appeal in human nutrition can be caused by their bloating effect and the content of some antinutritional compounds inhibiting the absorption of important nutrients. This study brings a comprehensive comparison of the nutrient content of pea flour after cooking and lactic fermentation before and after digestion in vitro. As a control sample, raw pea flour was used (sample 1). Raw pea flour was cooked for 10 min (sample 2) and 120 min (sample 3) at 100°C or it was fermented by Lactobacillus plantarum (sample 4) and cooked for 10 min at 100°C (sample 5). The samples were analyzed for protein and amino acids content, maltose, glucose, raffinose, total polyphenols, phytic acid, phytase, and mineral composition (P, Mg, Mn, Fe, Cu, Zn) before and after in vitro digestion. The results showed a significant (p < 0.05) increase in the protein digestibility of samples 3, 4 and 5. In the fermented samples were observed a higher concentration of Cys, Met, and Gln when compared to non-fermented samples. The fermentation of pea flour resulted in a significant (p < 0.05) decrease in glucose, maltose, and raffinose content. Cooking of pea flour for 10 and 120 min, but not fermenting, significantly (p < 0.05) decreased the polyphenols content. Cooking and fermentation together did not affect phytic acid concentration and phytase activity. Mg, Mn, Fe, Cu and, Zn concentration in pea flour was significantly (p < 0.05) decreased by cooking. On the other hand, fermentation significantly (p<0.05) improved the bioaccessibility of Mn and Fe. These findings suggest that lactic fermentation of pea flour is a promising culinary preparation that can improve the digestibility of peas.

Evidence for the Association between the Intronic Haplotypes of Ionotropic Glutamate Receptors and First-Episode Schizophrenia

The heritable component of schizophrenia (SCH) as a polygenic trait is represented by numerous variants from a heterogeneous group of genes each contributing a relatively small effect. Various SNPs have already been found and analyzed in genes encoding the NMDAR subunits. However, less is known about genetic variations of genes encoding the AMPA and kainate receptor subunits. We analyzed sixteen iGluR genes in full length to determine the sequence variability of iGluR genes. Our aim was to describe the rate of genetic variability, its distribution, and the co-occurrence of variants and to identify new candidate risk variants or haplotypes. The cumulative effect of genetic risk was then estimated using a simple scoring model. GRIN2A-B, GRIN3A-B, and GRIK4 genes showed significantly increased genetic variation in SCH patients. The fixation index statistic revealed eight intronic haplotypes and an additional four intronic SNPs within the sequences of iGluR genes associated with SCH (p < 0.05). The haplotypes were used in the proposed simple scoring model and moreover as a test for genetic predisposition to schizophrenia. The positive likelihood ratio for the scoring model test reached 7.11. We also observed 41 protein-altering variants (38 missense variants, four frameshifts, and one nonsense variant) that were not significantly associated with SCH. Our data suggest that some intronic regulatory regions of iGluR genes and their common variability are among the components from which the genetic predisposition to SCH is composed.

Predictive value of heart rate in treatment of major depression with ketamine in two controlled trials

OBJECTIVE

Ketamine has been shown to be effective in treatment of episodes of major depressive disorder (MDD). This controlled study aimed to analyse the predictive and discriminative power of heart rate (HR) and heart rate variability (HRV) for ketamine treatment in MDD.

METHODS

In 51 patients, HR and HRV were assessed at baseline before and during ketamine infusion and 24 hours post ketamine infusion. Montgomery-Åsberg Depression Rating Scale (MADRS) was used to assess changes of depressive symptoms. A 30% or 50% reduction of symptoms after 24 hours or within 7 days was defined as response. A linear mixed model was used for analysis.

RESULTS

Ketamine infusion increased HR and HRV power during and after infusion. Responders to ketamine showed a higher HR during the whole course of investigation, including at baseline with medium effect sizes (Cohen's d = 0.47-0.67). Furthermore, HR and HRV power discriminated between responders and non-responders, while normalized low and high frequencies did not.

CONCLUSION

The findings show a predictive value of HR and HRV power for ketamine treatment. This further underlines the importance of the autonomous nervous system (ANS) and its possible malfunctions in MDD.

SIGNIFICANCE

The predictive power of HR and HRV markers should be studied in prospective studies. Neurophysiological markers could improve treatment for MDD via optimizing the choice of treatments.

Simultaneous fMRI-EEG-Based Characterisation of NREM Parasomnia Disease: Methods and Limitations

Functional magnetic resonance imaging (fMRI) techniques and electroencephalography (EEG) were used to investigate sleep with a focus on impaired arousal mechanisms in disorders of arousal (DOAs). With a prevalence of 2–4% in adults, DOAs are significant disorders that are currently gaining attention among physicians. The paper describes a simultaneous EEG and fMRI experiment conducted in adult individuals with DOAs (n=10). Both EEG and fMRI data were validated by reproducing well established EEG and fMRI associations. A method for identification of both brain functional areas and EEG rhythms associated with DOAs in shallow sleep was designed. Significant differences between patients and controls were found in delta, theta, and alpha bands during awakening epochs. General linear models of the blood-oxygen-level-dependent signal have shown the secondary visual cortex and dorsal posterior cingulate cortex to be associated with alpha spectral power fluctuations, and the precuneus with delta spectral power fluctuations, specifically in patients and not in controls. Future EEG–fMRI sleep studies should also consider subject comfort as an important aspect in the experimental design.

Functional Connectivity Changes in Obsessive-Compulsive Disorder Correspond to Interference Control and Obsessions Severity

Introduction: Deficits in neurocognitive mechanisms such as inhibition control and cognitive flexibility have been suggested to mediate the symptoms in obsessive-compulsive disorder (OCD). These mechanisms are proposedly controlled by the "affective" and "executive" orbitofronto-striato-thalamo-cortical (CSTC) circuits with well-documented morphological and functional alterations in OCD that are associated with OCD symptoms. The precuneus region has been suggested in OCD as another key structure associated with the mechanism of "thought-action fusion." Our study aimed to elucidate the association of the altered functional coupling of the CSTC nodes (and precuneus), the OCD symptoms, and interference control/cognitive flexibility. Methods: In a group of 36 (17 medicated and 19 drug-free) OCD patients and matched healthy volunteers, we tested functional connectivity (FC) within the constituents of the dorsolateral prefrontal cortex "executive" CSTC, the orbitofrontal cortex/anterior cingulate "affective" CSTC, and precuneus. The functional connections showing the strongest effects were subsequently entered as explanatory variables to multiple regression analyses to identify possible associations between observed alterations of functional coupling and cognitive (Stroop test) and clinical measures (obsessions, compulsions, and anxiety level). Results: We observed increased FC (FWE p < 0.05 corr.) between CSTC seeds and regions of the parieto-occipital cortex, and between the precuneus and the angular gyrus and dorsolateral prefrontal cortex. Decreased FC was observed within the CSTC loop (caudate nucleus and thalamus) and between the anterior cingulate cortex and the limbic lobe. Linear regression identified a relationship between the altered functional coupling of thalamus with the right somatomotor parietal cortex and the Stroop color-word score. Similar association of thalamus FC has been identified also for obsessions severity. No association was observed for compulsions and anxiety. Conclusions: Our findings demonstrate altered FC in OCD patients with a prevailing increase in FC originating in CSTC regions toward other cortical areas, and a decrease in FC within the constituents of CSTC loops. Moreover, our results support the role of precuneus in OCD. The association of the cognitive and clinical symptoms with the FC between the thalamus and somatomotor cortex indicates that cognitive flexibility and inhibitory control are strongly linked and both mechanisms might contribute to the symptomatology of OCD.

The Ups and Downs of BACE1: Walking a Fine Line between Neurocognitive and Other Psychiatric Symptoms of Alzheimer's Disease

Although neurocognitive deficit is the best-recognized indicator of Alzheimer's disease (AD), psychotic and other noncognitive symptoms are the prime cause of institutionalization. BACE1 is the rate-limiting enzyme in the production of Aβ of AD, and one of the promising therapeutic targets in countering cognitive decline and amyloid pathology. Changes in BACE1 activity have also emerged to cause significant noncognitive neuropsychiatric symptoms and impairments of circadian rhythms, as evident from clinical trials and reports in transgenic models. In this study, we consider key characteristics of BACE1 with its contribution to neurocognitive deficit and other psychiatric symptoms of AD. We argue that a growing list of noncognitive mental impairments related to pharmacological modulation of BACE1 might present a major obstacle in clinical translation of emerging therapeutic leads targeting this protease. The adverse effects of BACE1 inhibition on mental health call for a revision of treatment strategies that assume indiscriminate inhibition of this key protease, and stress the need for further mechanistic and translational studies.

The Role of Zebrafish and Laboratory Rodents in Schizophrenia Research

Schizophrenia is a severe disorder characterized by positive, negative and cognitive symptoms, which are still not fully understood. The development of efficient antipsychotics requires animal models of a strong validity, therefore the aims of the article were to summarize the construct, face and predictive validity of schizophrenia models based on rodents and zebrafish, to compare the advantages and disadvantages of these models, and to propose future directions in schizophrenia modeling and indicate when it is reasonable to combine these models. The advantages of rodent models stem primarily from the high homology between rodent and human physiology, neurochemistry, brain morphology and circuitry. The advantages of zebrafish models stem in the high fecundity, fast development and transparency of the embryo. Disadvantages of both models originate in behavioral repertoires not allowing specific symptoms to be modeled, even when the models are combined. Especially modeling the verbal component of certain positive, negative and cognitive symptoms is currently impossible.

The Antidepressant Effect of Ketamine Is Dampened by Concomitant Benzodiazepine Medication

The rapid antidepressant effect of ketamine has become a breakthrough in the research and treatment of depression. Although predictive and modulating factors of the response to ketamine are broadly studied, little is known about optimal concurrent medication protocols. Concerning gamma-aminobutyric acid neurotransmission being a shared target for both ketamine and benzodiazepines (BZD), we evaluated the influence of BZD on the antidepressant effect of a single ketamine infusion in depressed patients. Data from 47 patients (27 females) with major depression (MADRS ≥ 20, ≥ 1 prior nonresponse to antidepressant treatment in current episode) who participated in two previous studies (EudraCT Number: 2009-010625-39 and 2013-000952-17) entered the analysis. All of the subjects were given an infusion of a subanesthetic dose of racemic ketamine (0.54 mg per kg) as an add-on medication to ongoing antidepressant treatment. Thirteen patients (28%) reached ≥ 50% reduction in MADRS within one week after ketamine administration. Nineteen (40%) patients took concomitant benzodiazepines on a daily basis. The doses of BZDs were significantly higher in nonresponders (p=0.007). ROC analysis distinguished responders from nonresponders by a criterion of >8mg of diazepam equivalent dose (DZ equivalent) with a sensitivity of 80% and a specificity of 85% (p<0.001). RM-ANOVA revealed a different time pattern of response to ketamine between the BZD+ (>8mg of DZ equivalent) and BZD- (≤8mg of DZ equivalent) groups, with a significantly worse outcome in BZD+ on day 3 (p=0.04) and day 7 (p=0.02). The results of the study indicate that concomitant benzodiazepine treatment in higher doses may attenuate ketamine's antidepressant effect. The pathophysiological, clinical and methodological implications of this finding should be considered in future research and ketamine treatment.

The effect of gabapentin and pregabalin on bone turnover and bone strength: A prospective study in Wistar rats

BACKGROUND

There are limited data on the effects of GBP on bone and no data for PGB. Some data suggest that there is a significant influence of sex hormone balance on the susceptibility of bone to antiepileptic drug-induced bone loss.

METHODS

Forty-eight male Wistar rats were divided into six groups that were subjected to two surgeries, sham (noORX) or real orchidectomy (ORX), and were fed three diets, a SLD, a SLD enriched with GBP or a SLD enriched with PGB. Dual energy X-ray absorptiometry was used to measure the bone mineral density. The concentrations of bone turnover markers were assayed. The femurs were biomechanically tested.

RESULTS

Significant reductions in bone mineral density, weight and biomechanical strength were observed in ORX animals. GBP or PGB exposure did not cause significant alterations in bone mineral density or biomechanical strength. No changes in bone turnover markers were observed, except for RANKL. A significant increase was found in the ORX GBP and ORX PGB groups. Within the orchidectomized animal group, RANKL levels were significantly higher in the ORX PGB group than in the ORX GBP group.

CONCLUSIONS

Because neither GBP nor PGB affected bone mineral density or mechanical bone strength, both of these antiepileptic drugs could be considered drugs with lower risks to bone health. A shift in RANKL levels indicates that the effects of GBP and PGB on osteoclast activity may be dependent on the hormonal status of animals.

Neural and neuronal discoordination in schizophrenia: From ensembles through networks to symptoms

Despite the substantial knowledge accumulated by past research, the exact mechanisms of the pathogenesis of schizophrenia and causal treatments still remain unclear. Deficits of cognition and information processing in schizophrenia are today often viewed as the primary and core symptoms of this devastating disorder. These deficits likely result from disruptions in the coordination of neuronal and neural activity. The aim of this review is to bring together convergent evidence of discoordinated brain circuits in schizophrenia at multiple levels of resolution, ranging from principal cells and interneurons, neuronal ensembles and local circuits, to large-scale brain networks. We show how these aberrations could underlie deficits in cognitive control and other higher order cognitive-behavioural functions. Converging evidence from both animal models and patients with schizophrenia is presented in an effort to gain insight into common features of deficits in the brain information processing in this disorder, marked by disruption of several neurotransmitter and signalling systems and severe behavioural outcomes.

Salivary gland function in thyroid cancer patients with radioiodine administration history

AIM

Radioiodine (RAI) improves survival in patients with locally advanced or metastatic differentiated thyroid carcinoma (DTC). Although there has been an ongoing debate on RAI-induced salivary gland damage, published data have been inconsistent. Therefore, the purpose of our study was to compare salivary gland function in intermediate and high risk DTC patients after single or repeated RAI treatment with their age- and sex-matched RAI-naive counterparts.

METHODS

Uptake and excretion of parotid and submandibular glands were quantitatively evaluated using ^99mTc-pertechnetate salivary gland scintigraphy in 23 patients previously treated with RAI. Patients (median 9.25 GBq ¹³¹I-NaI; Q1-Q3: 5.55-16.65; range: 5.55-27.5) were divided into subgroups according to previously administered ¹³¹I-NaI activity using cut-off values 5.55 GBq and 9.25 GBq. Their salivary gland scintigraphy results were compared with RAI-naive patients using Mann-Whitney test.

RESULTS

Compared to RAI-naive patients, parotid glands pertechnetate uptake was significantly lower in those treated with > 9.25 GBq (P=0.034) and parotid glands excretion fraction was already decreased with RAI activities > 5.55 GBq (P=0.031). In submandibular glands, no statistically significant difference in either function was observed even with RAI activity > 9.25 GBq.

CONCLUSION

Our data suggest that RAI therapy using activities ≤ 5.55 GBq does not substantially decrease saliva production. Activities > 5.55 GBq may lead to significant decrease in parotid excretion, and activities > 9.25 GBq also diminish parotid uptake. Surprisingly, submandibular glands, providing majority of seromucinous saliva under basal condition, seem to be unaffected even by RAI activities above 9.25 GBq.

Neonatal immune activation by lipopolysaccharide causes inadequate emotional responses to novel situations but no changes in anxiety or cognitive behavior in Wistar rats

Infection during the prenatal or neonatal stages of life is considered one of the major risk factors for the development of mental diseases such as schizophrenia or autism. However, the impacts of such an immune challenge on adult behavior are still not clear. In our study, we used a model of early postnatal immune activation by the application of bacterial endotoxin lipopolysaccharide (LPS) to rat pups at a dose of 2 mg/kg from postnatal day (PD) 5 to PD 9. In adulthood, the rats were tested in a battery of tasks probing various aspects of behavior: spontaneous activity (open field test), social behavior (social interactions and female bedding exploration), anxiety (elevated plus maze), cognition (active place avoidance in Carousel) and emotional response (ultrasonic vocalization recording). Moreover, we tested sensitivity to acute challenge with MK-801, a psychotomimetic drug. Our results show that the application of LPS led to increased self-grooming in the female bedding exploration test and inadequate emotional reactions in Carousel maze displayed by ultrasonic vocalizations. However, it did not have serious consequences on exploration, locomotion, social behavior or cognition. Furthermore, exposition to MK-801 did not trigger social or cognitive deficits in the LPS-treated rats. We conclude that the emotional domain is the most sensitive to the changes induced by neonatal immune activation in rats, including a disrupted response to novel and stressful situations in early adulthood (similar to that observed in human patients suffering from schizophrenia or autism), while other aspects of tested behavior remain unaffected.

Widespread white matter microstructural differences in schizophrenia across 4322 individuals: results from the ENIGMA Schizophrenia DTI Working Group

The regional distribution of white matter (WM) abnormalities in schizophrenia remains poorly understood, and reported disease effects on the brain vary widely between studies. In an effort to identify commonalities across studies, we perform what we believe is the first ever large-scale coordinated study of WM microstructural differences in schizophrenia. Our analysis consisted of 2359 healthy controls and 1963 schizophrenia patients from 29 independent international studies; we harmonized the processing and statistical analyses of diffusion tensor imaging (DTI) data across sites and meta-analyzed effects across studies. Significant reductions in fractional anisotropy (FA) in schizophrenia patients were widespread, and detected in 20 of 25 regions of interest within a WM skeleton representing all major WM fasciculi. Effect sizes varied by region, peaking at (d=0.42) for the entire WM skeleton, driven more by peripheral areas as opposed to the core WM where regions of interest were defined. The anterior corona radiata (d=0.40) and corpus callosum (d=0.39), specifically its body (d=0.39) and genu (d=0.37), showed greatest effects. Significant decreases, to lesser degrees, were observed in almost all regions analyzed. Larger effect sizes were observed for FA than diffusivity measures; significantly higher mean and radial diffusivity was observed for schizophrenia patients compared with controls. No significant effects of age at onset of schizophrenia or medication dosage were detected. As the largest coordinated analysis of WM differences in a psychiatric disorder to date, the present study provides a robust profile of widespread WM abnormalities in schizophrenia patients worldwide. Interactive three-dimensional visualization of the results is available at www.enigma-viewer.org.

EEG correlates of induced anxiety in obsessive-compulsive patients: comparison of autobiographical and general anxiety scenarios

BACKGROUND

The underlying symptomatology of obsessive-compulsive disorder (OCD) can be viewed as an impairment in both cognitive and behavioral inhibition, regarding difficult inhibition of obsessions and behavioral compulsions. Converging results from neuroimaging and electroencephalographic (EEG) studies have identified changes in activities throughout the medial frontal and orbital cortex and subcortical structures supporting the cortico-striato-thalamo-cortical circuit model of OCD. This study aimed to elucidate the electrophysiological changes induced by autobiographical and general anxiety scenarios in patients with OCD.

METHODS

Resting-state eyes-closed EEG data were recorded in 19 OCD patients and 15 healthy controls. Cortical EEG sources were estimated by standardized low-resolution electromagnetic tomography (sLORETA). The changes in the emotional state were induced by two different scenarios: the autobiographical script related to patient's OCD symptoms and the script triggering general anxiety.

RESULTS

During the resting state, we proved increased delta activity in the frontal, limbic and temporal lobe and the sub-lobar area in OCD patients. In a comparison of neural activities during general anxiety in OCD patients and the control group, we proved an increase in delta (parietal, temporal, occipital, frontal and limbic lobes, and sub-lobal area), theta (temporal, parietal and occipital lobes) and alpha-1 activities (parietal lobe). Finally, we explored the neural activity of OCD patients during exposure to the autobiographic scenario. We proved an increase in beta-3 activity (left frontal lobe).

CONCLUSION

Our study proved differences in neural activation in OCD patients and healthy controls during imagination of general anxiety. Exposure to the autobiographic OCD scenario leads to activation of left frontal brain areas. The results show the possibility of using specific scenarios in OCD therapy.

Individual prolactin reactivity modulates response of nucleus accumbens to erotic stimuli during acute cannabis intoxication: an fMRI pilot study

RATIONALE

Self-report studies indicate that cannabis could increase sexual desire in some users. We hypothesized that intoxication increases activation of brain areas responsive to visual erotica, which could be useful in the treatment of hypoactive sexual desire disorder, a condition marked by a lack of sexual desire.

OBJECTIVES

The aim of this study is to assess the aphrodisiacal properties of cannabis.

METHODS

We conducted an open-randomized study with 21 heterosexual casual cannabis users. A 3T MRI was used to measure brain activation in response to erotic pictures. Blood samples were collected to determine the serum levels of cannabinoids, cortisol and prolactin. Participants were grouped according to whether they had ever experienced any aphrodisiacal effects during intoxication (Group A) or not (Group non-A).

RESULTS

Intoxication was found to significantly increase activation in the right nucleus accumbens in the Group A while significantly decreasing activation in the Group non-A. There was also a significant interaction between the group and intoxication, with elevated prolactin in the Group non-A during intoxication. No intoxication-related differences in subjective picture evaluations were found.

CONCLUSION

Cannabis intoxication increases activation of the right nucleus accumbens to erotic stimuli. This effect is limited to users whose prolactin is not elevated in response to intoxication. This effect may be useful in the treatment of low sexual desire.

Endocannabinoid system in sexual motivational processes: Is it a novel therapeutic horizon?

The endocannabinoid system (ECS), which is composed of the cannabinoid receptors types 1 and 2 (CB1 and CB2) for marijuana's psychoactive ingredient Δ⁹-tetrahydrocannabinol (Δ⁹-THC), the endogenous ligands (AEA and 2-AG) and the enzymatic systems involved in their biosynthesis and degradation, recently emerged as important modulator of emotional and non-emotional behaviors. For centuries, in addition to its recreational actions, several contradictory claims regarding the effects of Cannabis use in sexual functioning and behavior (e.g. aphrodisiac vs anti-aphrodisiac) of both sexes have been accumulated. The identification of Δ⁹-THC and later on, the discovery of the ECS have opened a potential therapeutic target for sexual dysfunctions, given the partial efficacy of current pharmacological treatment. In agreement with the bidirectional modulation induced by cannabinoids on several behavioral responses, the endogenous cannabinoid AEA elicited biphasic effects on sexual behavior as well. The present article reviews current available knowledge on herbal, synthetic and endogenous cannabinoids with respect to the modulation of several aspects of sexuality in preclinical and human studies, highlighting their therapeutic potential.

Validity of Quinpirole Sensitization Rat Model of OCD: Linking Evidence from Animal and Clinical Studies

Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder with 1–3% prevalence. OCD is characterized by recurrent thoughts (obsessions) and repetitive behaviors (compulsions). The pathophysiology of OCD remains unclear, stressing the importance of pre-clinical studies. The aim of this article is to critically review a proposed animal model of OCD that is characterized by the induction of compulsive checking and behavioral sensitization to the D2/D3 dopamine agonist quinpirole. Changes in this model have been reported at the level of brain structures, neurotransmitter systems and other neurophysiological aspects. In this review, we consider these alterations in relation to the clinical manifestations in OCD, with the aim to discuss and evaluate axes of validity of this model. Our analysis shows that some axes of validity of quinpirole sensitization model (QSM) are strongly supported by clinical findings, such as behavioral phenomenology or roles of brain structures. Evidence on predictive validity is contradictory and ambiguous. It is concluded that this model is useful in the context of searching for the underlying pathophysiological basis of the disorder because of the relatively strong biological similarities with OCD.

Altered Neural Correlate of the Self-Agency Experience in First-Episode Schizophrenia-Spectrum Patients: An fMRI Study

BACKGROUND

The phenomenology of the clinical symptoms indicates that disturbance of the sense of self be a core marker of schizophrenia.

AIMS

To compare neural activity related to the self/other-agency judgment in patients with first-episode schizophrenia-spectrum disorders (FES, n = 35) and healthy controls (HC, n = 35).

METHOD

A functional magnetic resonance imaging (fMRI) using motor task with temporal distortion of the visual feedback was employed. A task-related functional connectivity was analyzed with the use of independent component analysis (ICA).

RESULTS

(1) During self-agency experience, FES showed a deficit in cortical activation in medial frontal gyrus (BA 10) and posterior cingulate gyrus, (BA 31; P < .05, Family-Wise Error [FWE] corrected). (2) Pooled-sample task-related ICA revealed that the self/other-agency judgment was dependent upon anti-correlated default mode and central-executive networks (DMN/CEN) dynamic switching. This antagonistic mechanism was substantially impaired in FES during the task.

DISCUSSION

During self-agency experience, FES demonstrate deficit in engagement of cortical midline structures along with substantial attenuation of anti-correlated DMN/CEN activity underlying normal self/other-agency discriminative processes.

Electrophysiological correlates of bilateral and unilateral repetitive transcranial magnetic stimulation in patients with bipolar depression

Repetitive transcranial magnetic stimulation (rTMS) has been demonstrated to have efficacy in the treatment of unipolar depression but limited research has explored the efficacy of rTMS in bipolar depression. Therefore, we conducted a comparative clinical trial evaluating clinical responses to prefrontal bilateral and unilateral rTMS in patients suffering from bipolar depression. We hypothesized that, 1) the response to the treatment would be associated with a decrease in the frequency of beta waves, 2) bilateral stimulation of the cortex would bring about more extensive changes in brain activity than unilateral stimulation, and 3) bilateral stimulation is more effective than unilateral. Thirty patients with bipolar depression were divided into two groups. Bilateral Group (n=15) who received rTMS in the left DLPFC (10Hz) and right DLPFC (1-Hz), and unilateral group (n=15) who received the stimulation only in the right DLPFC (1-Hz) during 20 treatment sessions. The proportion of responders in the bilateral stimulation group was significantly higher than that in the unilateral group [80% versus 47%]. The remission rate was 40% in the bilateral group and 40% in the unilateral group (not significant). In the responders to bilateral rTMS treatment, a significant reduction of alpha1-2, beta 1-3, and gamma frequencies were observed in medial and superior frontal and cingulate gyrus . Responders to the unilateral treatment showed decrease of gamma frequency in postcentral gyrus, precuneus, superior and inferior parietal lobule, Cuneus and angular gyrus. In conclusion, we found that bilateral stimulation was more effective than the unilateral stimulation and evidence that beta frequency activity could possibly be used as a marker for response to rTMS.

Profile measurements of the electron temperature on the ASDEX Upgrade, COMPASS, and ISTTOK tokamak using Thomson scattering, triple, and ball-pen probes

The ball-pen probe (BPP) technique is used successfully to make profile measurements of the electron temperature on the ASDEX Upgrade (Axially Symmetric Divertor Experiment), COMPASS (COMPact ASSembly), and ISTTOK (Instituto Superior Tecnico TOKamak) tokamak. The electron temperature is provided by a combination of the BPP potential (ΦBPP) and the floating potential (Vfl) of the Langmuir probe (LP), which is compared with the Thomson scattering diagnostic on ASDEX Upgrade and COMPASS. Excellent agreement between the two diagnostics is obtained for circular and diverted plasmas and different heating mechanisms (Ohmic, NBI, ECRH) in deuterium discharges with the same formula Te = (ΦBPP - Vfl)/2.2. The comparative measurements of the electron temperature using BPP/LP and triple probe (TP) techniques on the ISTTOK tokamak show good agreement of averaged values only inside the separatrix. It was also found that the TP provides the electron temperature with significantly higher standard deviation than BPP/LP. However, the resulting values of both techniques are well in the phase with the maximum of cross-correlation function being 0.8.

In search of neural mechanisms of mirror neuron dysfunction in schizophrenia: resting state functional connectivity approach

It has been repeatedly shown that schizophrenia patients have immense alterations in goal-directed behaviour, social cognition, and social interactions, cognitive abilities that are presumably driven by the mirror neurons system (MNS). However, the neural bases of these deficits still remain unclear. Along with the task-related fMRI and EEG research tapping into the mirror neuron system, the characteristics of the resting state activity in the particular areas that encompass mirror neurons might be of interest as they obviously determine the baseline of the neuronal activity. Using resting state fMRI, we investigated resting state functional connectivity (FC) in four predefined brain structures, ROIs (inferior frontal gyrus, superior parietal lobule, premotor cortex and superior temporal gyrus), known for their mirror neurons activity, in 12 patients with first psychotic episode and 12 matched healthy individuals. As a specific hypothesis, based on the knowledge of the anatomical inputs of thalamus to all preselected ROIs, we have investigated the FC between thalamus and the ROIs. Of all ROIs included, seed-to-voxel connectivity analysis revealed significantly decreased FC only in left posterior superior temporal gyrus (STG) and the areas in visual cortex and cerebellum in patients as compared to controls. Using ROI-to-ROI analysis (thalamus and selected ROIs), we have found an increased FC of STG and bilateral thalamus whereas the FC of these areas was decreased in controls. Our results suggest that: (1) schizophrenia patients exhibit FC of STG which corresponds to the previously reported changes of superior temporal gyrus in schizophrenia and might contribute to the disturbances of specific functions, such as emotional processing or spatial awareness; (2) as the thalamus plays a pivotal role in the sensory gating, providing the filtering of the redundant stimulation, the observed hyperconnectivity between the thalami and the STGs in patients with schizophrenia might explain the sequential overload with sensory inputs that leads to the abnormal cognitive processing.

ISPD gene homozygous deletion identified by SNP array confirms prenatal manifestation of Walker-Warburg syndrome

Walker-Warburg syndrome (WWS) is a rare form of autosomal recessive, congenital muscular dystrophy that is associated with brain and eye anomalies. Several genes encoding proteins involved in abnormal α-dystroglycan glycosylation have been implicated in the aetiology of WWS, most recently the ISPD gene. Typical WWS brain anomalies, such as cobblestone lissencephaly, hydrocephalus and cerebellar malformations, can be prenatally detected through routine ultrasound examinations. Here, we report two karyotypically normal foetuses with multiple brain anomalies that corresponded to WWS symptoms. Using a SNP-array examination on the amniotic fluid DNA, a homozygous microdeletion was identified at 7p21.2p21.1 within the ISPD gene. Published data and our findings led us to the conclusion that a homozygous segmental intragenic deletion of the ISPD gene causes the most severe phenotype of Walker-Warburg syndrome. Our results also clearly supports the use of chromosomal microarray analysis as a first-line diagnostic test in patients with a foetus with one or more major structural abnormalities identified on ultrasonographic examination.

Prothrombotic changes due to an increase in thyroid hormone levels

OBJECTIVE

With increasing free thyroxine levels, a gradually rising risk of venous thromboembolism has been described in case-control studies. However, reports on the influence of thyroid hormones on haemostasis, while suggesting a hypercoagulable state in thyrotoxicosis, have often been inconclusive. This study evaluates multiple markers of haemostasis and fibrinolysis in a paired design, making it more sensitive to changes in thyroid hormone levels.

DESIGN

We analysed multiple variables in patients who shifted from severe hypothyroidism to mild hyperthyroidism during thyroid cancer treatment. Those with possible residual disease were excluded.

METHODS

Ninety patients following total thyroidectomy were tested on two occasions: i) before radioiodine remnant ablation and ii) 6 weeks later, on levothyroxine (lT4) suppression treatment, and the results were compared using the Wilcoxon's test for paired data.

RESULTS

During lT4 treatment, significant increases (all P<0.001) in fibrinogen (from median 3.4 to 3.8 g/l), von Willebrand factor (from 85 to 127%), factor VIII (from 111 to 148%) and plasminogen activator inhibitor 1 (from 6.5 to 13.9 μg/l) were observed. In addition, the activation times of platelet adhesion and aggregation stimulated with collagen and epinephrine (EPI)/ADP, i.e. closure times in platelet function analyser (PFA-100), were significantly shortened (P<0.001): for EPI from median 148 to 117 s and for ADP from 95 to 80 s. Changes in other tests were less prominent or insignificant.

CONCLUSIONS

An increase in thyroid hormone levels shifts the haemostatic balance towards a hypercoagulable, hypofibrinolytic state. This may contribute to the increased cardiovascular morbidity and mortality observed even in mild thyrotoxicosis.

Sad mood induction has an opposite effect on amygdala response to emotional stimuli in euthymic patients with bipolar disorder and healthy controls

BACKGROUND

Aberrant amygdala reactivity to affective stimuli represents a candidate factor predisposing patients with bipolar disorder (BD) to relapse, but it is unclear to what extent amygdala reactivity is state-dependent. We evaluated the modulatory influence of mood on amygdala reactivity and functional connectivity in patients with remitted BD and healthy controls.

METHODS

Amygdala response to sad versus neutral faces was investigated using fMRI during periods of normal and sad mood induced by autobiographical scripts. We assessed the functional connectivity of the amygdala to characterize the influence of mood state on the network responsible for the amygdala response.

RESULTS

We included 20 patients with remitted BD and 20 controls in our study. The sad and normal mood exerted opposite effects on the amygdala response to emotional faces in patients compared with controls (F1,38 = 5.85, p = 0.020). Sad mood amplified the amygdala response to sad facial stimuli in controls but attenuated the amygdala response in patients. The groups differed in functional connectivity between the amygdala and the inferior prefrontal gyrus (p ≤ 0.05, family-wise error-corrected) of ventrolateral prefrontal cortex (vlPFC) corresponding to Brodmann area 47. The sad mood challenge increased connectivity during the period of processing sad faces in patients but decreased connectivity in controls.

LIMITATIONS

Limitations to our study included long-term medication use in the patient group and the fact that we mapped only depressive (not manic) reactivity.

CONCLUSION

Our results support the role of the amygdala-vlPFC as the system of dysfunctional contextual affective processing in patients with BD. Opposite amygdala reactivity unmasked by the mood challenge paradigm could represent a trait marker of altered mood regulation in patients with BD.

White matter changes in first episode psychosis and their relation to the size of sample studied: a DTI study

BACKGROUND

White matter abnormality has been recently proposed as a pathophysiological feature of schizophrenia (SZ). However, most of the data available has been gathered from chronic patients, and was therefore possibly confounded by factors such as duration of the disease, and treatment received. The extent and localization of these changes is also not clear.

METHODS

We examined a population of early stage SZ patients using diffusion tensor imaging (DTI). 77 SZ patients and 60 healthy controls (HCs) were included in the analysis using Tract-Based Spatial Statistics (TBSS). We have also analyzed 250 randomly created subsets of the original cohort, to investigate the relation between the result of TBSS analysis, and the size of the sample studied.

RESULTS

We have found a significant decrease in fractional anisotropy (FA) in the patient group. This change is present in most major white matter (WM) tracts including the corpus callosum, superior and inferior longitudinal fasciculi, inferior fronto-occipital fasciculus, and posterior thalamic radiation. Furthermore, we identified a clear trend towards an increase in the number and spatial extent of significant voxels reported, with an increasing number of subjects included in the analysis.

CONCLUSION

Our study shows that FA is significantly decreased in patients at an early stage of schizophrenia, and that the extent of this finding is dependent on the size of studied sample; therefore underpowered studies might produce results with false spatial localization.

Biochemical, histopathological and morphological profiling of a rat model of early immune stimulation: relation to psychopathology

Perinatal immune challenge leads to neurodevelopmental dysfunction, permanent immune dysregulation and abnormal behaviour, which have been shown to have translational validity to findings in human neuropsychiatric disorders (e.g. schizophrenia, mood and anxiety disorders, autism, Parkinson’s disease and Alzheimer’s disease). The aim of this animal study was to elucidate the influence of early immune stimulation triggered by systemic postnatal lipopolysaccharide administration on biochemical, histopathological and morphological measures, which may be relevant to the neurobiology of human psychopathology. In the present study of adult male Wistar rats we examined the brain and plasma levels of monoamines (dopamine, serotonin), their metabolites, the levels of the main excitatory and inhibitory neurotransmitters glutamate and γ-aminobutyric acid and the levels of tryptophan and its metabolites from the kynurenine catabolic pathway. Further, we focused on histopathological and morphological markers related to pathogenesis of brain diseases - glial cell activation, neurodegeneration, hippocampal volume reduction and dopaminergic synthesis in the substantia nigra. Our results show that early immune stimulation in adult animals alters the levels of neurotransmitters and their metabolites, activates the kynurenine pathway of tryptophan metabolism and leads to astrogliosis, hippocampal volume reduction and a decrease of tyrosine hydroxylase immunoreactivity in the substantia nigra. These findings support the crucial pathophysiological role of early immune stimulation in the above mentioned neuropsychiatric disorders.

Denosumab associated with bone density increase and clinical improvement in a long-term hemodialysis patient. Case report and review of the literature

Denosumab is a human monoclonal antibody representing a novel therapy of osteoporosis. Contrary to always other antiosteoporotic drugs, it is not contraindicated in advanced chronic kidney disease, as its pharmacokinetic does not differ from patients with normal kidney function. However, published case reports in chronic kidney disease (CKD) patients stopped the therapy after single dose because of hypocalcemia. We present a case of successful treatment of osteoporosis in a young hemodialysis patient with repeated denosumab doses.