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Introduction: Vocal and motor tics are characteristic for Tic disorders (TD) and Tourette's syndrome (APA 2022). Because of the pathophysiology of the disorders not being fully understood and the presence of the externally measurable symptoms; great attention has been paid to the cortico-striatal regions of patients with TD. In addition to the alterations in motor symptoms patients can experience a premonitory urge (PU) which can be felt before a tic (Reese et al. Behav. Ther. 2014; 45 177–186). Previous studies found an impact of these urges on sensory perception, attention and social cognition as well as an involvement of the brain regions insula, anterior cingulate cortex (ACC) and the temporoparietal junction (TPJ) (Seeley J. Neurosci. 2019; 39 9878–9882, Kucyi et al. J. Neurophysiol. 2012; 108 3382–3392, Uddin et al. Brain Topogr. 2019; 32 926–942). These findings lead to the idea of altered functional connectivity of the salience network (SN) in patients with TD. Objectives: This study aims to investigate the connectivity changes of the SN in patients with TD. We examined functional resting-state scans of patients with TD and searched for possible correlations between the tic and PU severity and the connectivity of the SN. Methods: 21 Patients (mean age: 30.9 years ± 10.0 [range = 19–57], 6 females) diagnosed with TD, and 20 healthy controls (mean age: 29.7 years ± 8.9 [range = 18–50], 5 females) underwent a resting-state fMRI scan. Functional and anatomical images were conducted on a 3T Siemens Prisma fit MRI scanner. PU and tic severity were measured by the Premonitory Urges for Tics Scale (PUTS) and the Yale Global Tic Severity Scale (YGTSS). The connectivity analysis of the resting-state scans was done using the CONN toolbox v21.a. After pre-processing and de-noising steps, a whole-brain seed-based connectivity analysis was carried out with the seeds being the major cortical nods of the SN. For the correlation analysis a linear regression of the YGTSS score/PUTS score and the brain connectivity of the seed regions was conducted. Results: The PUTS score was 25.3±5.4 (range 10-33) and the YGTSS total tic score was 23.1±7.9 (range 10-38) for the patients. The connectivity analysis revealed a significant difference in connectivity between the groups for the ACC, the right insula and the TPJ. A negative correlation between the YGTSS scores and the connectivity of the left insula and the right superior frontal gyrus (SFG) was shown in the correlation analysis. No significant correlation was found for the PUTS scores in the investigated seed regions. Conclusions: The right SFG mediates motor urgency and inhibitory control. Since we found a negative correlation between the insula and the right SFG regarding to higher YGTSS scores of the patients, our results might shed some light on the pathophysiology regarding lower inhibitory control in patients which experience higher tic severity. Disclosure of Interest: None Declared [ABSTRACT FROM AUTHOR]

Objectives: The development of integrated magnetic resonance (MR)-positron emission tomography (PET) hybrid imaging opens up new horizons for imaging in neuro-oncology. In cerebral gliomas the definition of tumour extent may be difficult to ascertain using standard MR imaging (MRI) only. The differentiation of post-therapeutic scar tissue, tumour rests and tumour recurrence is challenging. The relationship to structures such as the pyramidal tract to the tumour mass influences the therapeutic neurosurgical approach.Methods: The diagnostic information may be enriched by sophisticated MR techniques such as diffusion tensor imaging (DTI), multiple-volume proton MR spectroscopic imaging (MRSI) and functional MRI (fMRI). Metabolic imaging with PET, especially using amino acid tracers such as (18)F-fluoroethyl-L-tyrosine (FET) or (11)C-L-methionine (MET) will indicate tumour extent and response to treatment.Results: The new technologies comprising MR-PET hybrid systems have the advantage of providing comprehensive answers by a one-stop-job of 40-50 min. The combined approach provides data of different modalities using the same iso-centre, resulting in optimal spatial and temporal realignment. All images are acquired exactly under the same physiological conditions.Conclusions: We describe the imaging protocol in detail and provide patient examples for the different imaging modalities such as FET-PET, standard structural imaging (T1-weighted, T2-weighted, T1-weighted contrast agent enhanced), DTI, MRSI and fMRI.Key Points: Hybrid MR-PET opens up new horizons in neuroimaging. Hybrid MR-PET allows brain tumour assessment in one stop. Hybrid MR-PET allows simultaneous acquisition of structural, functional and molecular images. [ABSTRACT FROM AUTHOR]

Abstract Background Tourette syndrome is a neuropsychiatric disorder characterized by motor and phonic tics. Deficient motor inhibition underlying tics is one of the main hypotheses in its pathophysiology. Therefore the question arises whether this supposed deficient motor inhibition affects also voluntary movements. Despite severe motor tics, different personalities who suffer from Tourette perform successfully as neurosurgeon, pilot or professional basketball player. Methods For the investigation of fine motor skills we conducted a motor performance test battery in an adult Tourette sample and an age matched group of healthy controls. Results The Tourette patients showed a significant lower performance in the categories steadiness of both hands and aiming of the right hand in comparison to the healthy controls. A comparison of patients’ subgroup without comorbidities or medication and healthy controls revealed a significant difference in the category steadiness of the right hand. Conclusions Our results show that steadiness and visuomotor integration of fine motor skills are altered in our adult sample but not precision and speed of movements. This alteration pattern might be the clinical vignette of complex adaptations in the excitability of the motor system on the basis of altered cortical and subcortical components. The structurally and functionally altered neuronal components could encompass orbitofrontal, ventrolateral prefrontal and parietal cortices, the anterior cingulate, amygdala, primary motor and sensorimotor areas including altered corticospinal projections, the corpus callosum and the basal ganglia.

We present the concept of a solar thermo-photovoltaic (STPV) collection system based on a large-area, nanoimprint-patterned film of plasmonic structures acting as an integrated solar absorber/narrow-band thermal emitter (SANTE). The SANTE film concept is based on integrating broad-band solar radiation absorption with selective narrow-band thermal IR radiation which can be efficiently coupled to a photovoltaic (PV) cell for power generation. By employing a low reflectivity refractory metal (e.g., tungsten) as a plasmonic material, we demonstrate that the absorption spectrum of the SANTE film can be designed to be broad-band in the visible range and narrow-band in the infrared range. A detailed balance calculation demonstrates that the total STPV system efficiency exceeds the Shockley–Queisser limit for emitter temperatures above Te = 1200 K, and achieves an efficiency as high as 41% for Te = 2300 K. Emitter temperatures in this range are shown to be achievable under modest sun concentrations (less than 1000 suns) due to the thermal insulation provided by the SANTE film. An experimental demonstration of the wide-angle, frequency-selective absorptivity is presented. [ABSTRACT FROM AUTHOR]

Major depressive disorder (MDD) typically manifests itself in depressed affect, anhedonia, low energy, and additional symptoms. Despite its high global prevalence, its pathophysiology still gives rise to questions. Current research places alterations in functional connectivity among MDD's most promising biomarkers. However, given the heterogeneity of previous findings, the use of higher-resolution imaging techniques, like ultra-high field (UHF) fMRI (≥7 Tesla, 7T), may offer greater specificity in delineating fundamental impairments. In this study, 7T UHF fMRI scans were conducted on 31 MDD patients and 27 age-gender matched healthy controls to exploratorily contrast cerebral resting-state functional connectivity patterns between both groups. The CONN toolbox was used to generate functional network connectivity (FNC) analysis based on the region of interest (ROI)-to-ROI correlations in order to enable the identification of clusters of significantly different connections. Correction for multiple comparisons was implemented at the cluster level using a false discovery rate (FDR). The analysis revealed three significant clusters differentiating MDD patients and healthy controls. In Clusters 1 and 2, MDD patients exhibited between-network hypoconnectivity in basal ganglia-cortical pathways as well as hyperconnectivity in thalamo-cortical pathways, including several individual ROI-to-ROI connections. In Cluster 3, they showed increased occipital interhemispheric within-network connectivity. These findings suggest that alterations in basal ganglia-thalamo-cortical circuits play a substantial role in the pathophysiology of MDD. Furthermore, they indicate potential MDD-related deficits relating to a combination of perception (vision, audition, and somatosensation) as well as more complex functions, especially social-emotional processing, modulation, and regulation. It is anticipated that these findings might further inform more accurate clinical procedures for addressing MDD., (© 2024. The Author(s).)

Aims: Metamizole is quite an old drug with analgesic, antipyretic and spasmolytic properties. Recent findings have shown that it may induce several cytochrome P450 (CYP) enzymes, especially CYP3A4 and CYP2B6. The clinical relevance of these properties is uncertain. We aimed to unravel potential pharmacokinetic interactions between metamizole and the CYP3A4 substrate quetiapine., Methods: Plasma concentrations of quetiapine from a large therapeutic drug monitoring database were analysed. Two groups of 33 patients, either receiving quetiapine as a monotherapy (without CYP modulating comedications) or with concomitantly applied metamizole, were compared addressing a potential impact of metamizole on the metabolism of quetiapine being reflected in differences of plasma concentrations of quetiapine and dose-adjusted plasma concentrations., Results: Patients comedicated with metamizole showed >50% lower plasma concentrations of quetiapine (median 45.2 ng/mL, Q 1  = 15.5; Q 3  = 90.5 vs. 92.0 ng/mL, Q 1  = 52.3; Q 3  = 203.8, P = .003). The dose-adjusted plasma concentrations were 69% lower in the comedication group (P = .001). Subgroup analyses did not suggest a dose dependency of the metamizole effect or an influence of quetiapine formulation (immediate vs. extended release). Finally, the comedication group exhibited a significantly higher proportion of patients whose quetiapine concentrations were below the therapeutic reference range (78.8% in the metamizole group vs. 54.4% in the control group, P = .037) indicating therapeutically insufficient drug concentrations., Conclusion: The combination of metamizole and quetiapine leads to significantly lower drug concentrations of quetiapine, probably via an induction of CYP3A4. Clinicians must consider the risk of adverse drug reactions, especially treatment failure under quetiapine when adding metamizole., (© 2024 The Author(s). British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)