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1.
Schizophr Bull ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641344

RESUMO

BACKGROUND: Ventral striatal hypoactivation during reward anticipation has consistently been observed in patients with schizophrenia. In addition, that hypoactivation has been shown to correlate negatively with negative symptoms, and in particular with apathy. However, little is known about the stability of these results over time and their reliability across different centers. METHODS: In total, 67 patients with schizophrenia (15 females) and 55 healthy controls (13 females) were recruited in 2 centers in Switzerland and Germany. To assess the neural bases of reward anticipation, all participants performed a variant of the Monetary Incentive Delay task while undergoing event-related functional magnetic resonance imaging at baseline and after 3 months. Stability over time was measured using intra-class correlation (ICC(A,1)) and stability between centers was measured with mixed models. RESULTS: Results showed the expected ventral striatal hypoactivation in patients compared to controls during reward anticipation. We showed that these results were stable across centers. The primary analysis did not reveal an effect of time. Test-retest reliability was moderate for controls, and poor for patients. We did not find an association between ventral striatal hypoactivation and negative symptoms in patients. CONCLUSIONS: Our results align with the hypothesis that ventral striatal activation is related to modulation of motivational saliency during reward anticipation. They also confirm that patients with schizophrenia show impaired reward anticipation. However, the poor test-retest reliability and the absence of an association with symptoms suggests that further research is needed before ventral striatal activity can be used as a biomarker on the individual patient level.

2.
Schizophr Bull ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577901

RESUMO

BACKGROUND AND HYPOTHESIS: Abnormal thalamic nuclei volumes and their link to cognitive impairments have been observed in schizophrenia. However, whether and how this finding extends to the schizophrenia spectrum is unknown. We hypothesized a distinct pattern of aberrant thalamic nuclei volume across the spectrum and examined its potential associations with cognitive symptoms. STUDY DESIGN: We performed a FreeSurfer-based volumetry of T1-weighted brain MRIs from 137 healthy controls, 66 at-risk mental state (ARMS) subjects, 89 first-episode psychosis (FEP) individuals, and 126 patients with schizophrenia to estimate thalamic nuclei volumes of six nuclei groups (anterior, lateral, ventral, intralaminar, medial, and pulvinar). We used linear regression models, controlling for sex, age, and estimated total intracranial volume, both to compare thalamic nuclei volumes across groups and to investigate their associations with positive, negative, and cognitive symptoms. STUDY RESULTS: We observed significant volume alterations in medial and lateral thalamic nuclei. Medial nuclei displayed consistently reduced volumes across the spectrum compared to controls, while lower lateral nuclei volumes were only observed in schizophrenia. Whereas positive and negative symptoms were not associated with reduced nuclei volumes across all groups, higher cognitive scores were linked to lower volumes of medial nuclei in ARMS. In FEP, cognition was not linked to nuclei volumes. In schizophrenia, lower cognitive performance was associated with lower medial volumes. CONCLUSIONS: Results demonstrate distinct thalamic nuclei volume reductions across the schizophrenia spectrum, with lower medial nuclei volumes linked to cognitive deficits in ARMS and schizophrenia. Data suggest a distinctive trajectory of thalamic nuclei abnormalities along the course of schizophrenia.

3.
Brain ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608149

RESUMO

Adaptive coding of reward is the process by which neurons adapt their response to the context of available compensations. Higher rewards lead to a stronger brain response, but the increase of the response depends on the range of available rewards. A steeper increase is observed in a narrow range, and a more gradual slope in a wider range. In schizophrenia, adaptive coding appears affected in different domains, and in the reward domain in particular. Here we tested adaptive coding of reward in a large group of patients with schizophrenia (N = 86) and controls (N = 66). We assessed 1) the association between adaptive coding deficits and symptoms; 2) the longitudinal stability of deficits (the same task was performed three months apart); 3) the stability of results between two experimental sites. We used fMRI and the Monetary Incentive Delay task to assess participant' adaptation to two different reward ranges: a narrow and a wide range. We used a region of interest analysis, evaluating adaptation within striatal and visual regions. Patients and controls underwent a full demographic and clinical assessment. We found reduced adaptive coding in patients, due to a decreased slope in the narrow reward range, with respect to that of control participants in striatal but not visual regions. This pattern was observed at both research sites. Upon re-test, patients increased their narrow range slopes, showing improved adaptive coding, whereas controls slightly reduced them. At re-test, patients with overly steep slopes in the narrow range also showed higher levels of negative symptoms. Our data confirm deficits in reward adaptation in schizophrenia and reveal a practice effect in patients, leading to improvement, with steeper slopes upon retest. However, in some patients, an overly steep slope may result in poor discriminability of larger rewards, due to early saturation of the brain response. Together, the loss of precision of reward representation in new (first exposure, underadaptation) and more familiar (re-test, overadaptation) situations may contribute to the multiple motivational symptoms in schizophrenia.

4.
Mol Psychiatry ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671214

RESUMO

Formal thought disorder (FTD) is a clinical key factor in schizophrenia, but the neurobiological underpinnings remain unclear. In particular, the relationship between FTD symptom dimensions and patterns of regional brain volume loss in schizophrenia remains to be established in large cohorts. Even less is known about the cellular basis of FTD. Our study addresses these major obstacles by enrolling a large multi-site cohort acquired by the ENIGMA Schizophrenia Working Group (752 schizophrenia patients and 1256 controls), to unravel the neuroanatomy of FTD in schizophrenia and using virtual histology tools on implicated brain regions to investigate the cellular basis. Based on the findings of previous clinical and neuroimaging studies, we decided to separately explore positive, negative and total formal thought disorder. We used virtual histology tools to relate brain structural changes associated with FTD to cellular distributions in cortical regions. We identified distinct neural networks positive and negative FTD. Both networks encompassed fronto-occipito-amygdalar brain regions, but positive and negative FTD demonstrated a dissociation: negative FTD showed a relative sparing of orbitofrontal cortical thickness, while positive FTD also affected lateral temporal cortices. Virtual histology identified distinct transcriptomic fingerprints associated for both symptom dimensions. Negative FTD was linked to neuronal and astrocyte fingerprints, while positive FTD also showed associations with microglial cell types. These results provide an important step towards linking FTD to brain structural changes and their cellular underpinnings, providing an avenue for a better mechanistic understanding of this syndrome.

5.
BJPsych Open ; 10(3): e80, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38616714

RESUMO

BACKGROUND: Among important dimensions related to the use of coercive measures, professionals' attitude towards coercion is of particular interest. Little is known about how experiences of violence in the workplace might influence these attitudes. AIMS: The present study aimed to investigate potential correlates of attitudes towards coercion, especially experiences of violence in the workplace. METHOD: Mental health professionals were contacted through an online survey to assess their attitudes towards coercion using the Staff Attitude to Coercion Scale (SACS). The three subscales of the SACS (critical, pragmatic and positive attitudes) were analysed in a multivariate multiple linear regression, using a set of covariates including experiences of violence in the workplace. We hypothesised that experience of violence in the workplace would correlate with less critical attitudes of staff members towards coercion. RESULTS: A total of 423 professionals were included in the regression analysis. Age, professional category, feeling of insecurity, having witnessed or used coercion, and the emotional burden associated with coercive measures had a joint significant effect on the three SACS subscales. A feeling of insecurity, but not the experience of violence, was associated with a less critical, more positive appraisal of coercive measures. The emotional burden related to the use of coercion was associated with a more critical attitude. CONCLUSIONS: The present results highlight the importance of considering staff members' training and well-being regarding their feelings of insecurity when addressing attitudes towards coercion. The experience of patients should be integrated into staff training and coercion reduction programmes.

6.
Sci Adv ; 10(11): eadi7598, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489363

RESUMO

Ultrafast optical control of quantum systems is an emerging field of physics. In particular, the possibility of light-driven superconductivity has attracted much of attention. To identify nonequilibrium superconductivity, it is necessary to measure fingerprints of superconductivity on ultrafast timescales. Recently, nonlinear THz third-harmonic generation (THG) was shown to directly probe the collective degrees of freedoms of the superconducting condensate, including the Higgs mode. Here, we extend this idea to light-driven nonequilibrium states in superconducting La2-xSrxCuO4, establishing an optical pump-THz-THG drive protocol to access the transient superconducting order-parameter quench and recovering on few-picosecond timescales. We show in particular the ability of two-dimensional TH spectroscopy to disentangle the effects of optically excited quasiparticles from the pure order-parameter dynamics, which are unavoidably mixed in the pump-driven linear THz response. Benchmarking the gap dynamics to existing experiments shows the ability of driven THG spectroscopy to overcome these limitations in ordinary pump-probe protocols.

7.
Schizophr Res ; 267: 182-190, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38554698

RESUMO

BACKGROUND: The clinical profiles of methamphetamine-induced psychosis (MIP) and schizophrenia are largely overlapping making differentiation challenging. In this systematic review and meta-analysis, we aim to compare the positive and negative symptoms of MIP and schizophrenia to better understand the differences between them. STUDY DESIGN: In accordance with our pre-registered protocol (CRD42021286619), we conducted a search of English-language studies up to December 16th, 2022, in PubMed, EMBASE, and PsycINFO, including stable outpatients with MIP and schizophrenia. We used the Newcastle-Ottawa Scale to measure the quality of cross-sectional, case-control, and cohort studies. STUDY RESULTS: Of the 2052 articles retrieved, we included 12 studies (6 cross-sectional, 3 case-control, and 2 cohort studies) in our meta-analysis, involving 624 individuals with MIP and 524 individuals with schizophrenia. Our analysis found no significant difference in positive symptoms between the two groups (SMD, -0.01; 95%CI, -0.13 to +0.11; p = 1). However, individuals with MIP showed significantly less negative symptoms compared to those with schizophrenia (SMD, -0.35; 95CI%, -0.54 to -0.16; p = 0.01; I2 = 54 %). Our sensitivity analysis, which included only studies with a low risk of bias, did not change the results. However, our meta-analysis is limited by its cross-sectional approach, which limits the interpretation of causal associations. Furthermore, differences in population, inclusion criteria, methodology, and drug exposure impact our findings. CONCLUSIONS: Negative symptoms are less prominent in individuals with MIP. While both groups do not differ regarding positive symptoms, raises the possibility of shared and partly different underlying neurobiological mechanisms related to MIP and schizophrenia.

8.
medRxiv ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38370846

RESUMO

Background: Schizophrenia is associated with an increased risk of aggressive behaviour, which may partly be explained by illness-related changes in brain structure. However, previous studies have been limited by group-level analyses, small and selective samples of inpatients and long time lags between exposure and outcome. Methods: This cross-sectional study pooled data from 20 sites participating in the international ENIGMA-Schizophrenia Working Group. Sites acquired T1-weighted and diffusion-weighted magnetic resonance imaging scans in a total of 2095 patients with schizophrenia and 2861 healthy controls. Measures of grey matter volume and white matter microstructural integrity were extracted from the scans using harmonised protocols. For each measure, normative modelling was used to calculate how much patients deviated (in z-scores) from healthy controls at the individual level. Ordinal regression models were used to estimate the associations of these deviations with concurrent aggressive behaviour (as odds ratios [ORs] with 99% confidence intervals [CIs]). Mediation analyses were performed for positive symptoms (i.e., delusions, hallucinations and disorganised thinking), impulse control and illness insight. Aggression and potential mediators were assessed with the Positive and Negative Syndrome Scale, Scale for the Assessment of Positive Symptoms or Brief Psychiatric Rating Scale. Results: Aggressive behaviour was significantly associated with reductions in total cortical volume (OR [99% CI] = 0.88 [0.78, 0.98], p = .003) and global white matter integrity (OR [99% CI] = 0.72 [0.59, 0.88], p = 3.50 × 10-5) and additional reductions in dorsolateral prefrontal cortex volume (OR [99% CI] = 0.85 [0.74, 0.97], p =.002), inferior parietal lobule volume (OR [99% CI] = 0.76 [0.66, 0.87], p = 2.20 × 10-7) and internal capsule integrity (OR [99% CI] = 0.76 [0.63, 0.92], p = 2.90 × 10-4). Except for inferior parietal lobule volume, these associations were largely mediated by increased severity of positive symptoms and reduced impulse control. Conclusions: This study provides evidence that the co-occurrence of positive symptoms, poor impulse control and aggressive behaviour in schizophrenia has a neurobiological basis, which may inform the development of therapeutic interventions.

9.
Nutrients ; 16(4)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38398834

RESUMO

Bariatric surgery candidates (BSC) are a highly vulnerable group for mental health impairments. According to the theoretical model of weight stigma, weight-related experienced stigmatization (ES) negatively influences mental health through weight bias internalization (WBI). This study tested this model among BSC and investigated whether this association depends on a negative body image in terms of weight and shape concern as a potential moderator. As part of a German multicenter study, ES, WBI, weight and shape concern, and depressive symptoms were assessed via self-report questionnaires among n = 854 BSC. Simple and moderated mediation analyses were applied to analyze whether WBI influences the relationship between ES and depressive symptoms, and whether this influence depends on weight and shape concern. WBI significantly mediated the relationship between ES and depressive symptoms by partially reducing the association of ES with depressive symptoms. Weight and shape concern emerged as significant moderators in the overall model and specifically for associations between WBI and depressive symptoms. The results suggest that the association between ES and depressive symptoms among BSC is stronger in those with high WBI. This association is strengthened by weight and shape concern, especially at low and mean levels. Studies evaluating longitudinal associations between weight-related stigmatization and mental health are indicated, as well as intervention studies targeting WBI in order to reduce adverse effects of ES on mental health in BSC.


Assuntos
Cirurgia Bariátrica , Obesidade , Humanos , Obesidade/complicações , Obesidade/cirurgia , Obesidade/psicologia , Peso Corporal , Estereotipagem , Depressão/etiologia , Depressão/psicologia , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/psicologia
10.
Obes Facts ; 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38350429

RESUMO

Introduction The Weight Bias Internalization Scale and the Modified Weight Bias Internalization Scale are well-established self-report questionnaires for assessing weight bias internalization, which is widespread among bariatric patients. However, among this group, psychometric properties of the Weight Bias Internalization Scale have only been examined in small samples showing unsatisfactory model fit and have not been explored for the modified questionnaire. Methods This study psychometrically evaluated and compared the Weight Bias Internalization Scale and Modified Weight Bias Internalization Scale in a large sample of prebariatric patients (N=825, mean age=46.75 years, SD=11.55) regarding item characteristics, model fit to unidimensionality, reliability, construct validity, and measurement invariance. Results Item 4 of both questionnaires showed low corrected item-total correlations (<.40) and was therefore removed from the scales. The new 10-item versions showed improved item characteristics, internal consistency, model fit to unidimensionality, and convergent and divergent validity when compared to the 11-item versions. The best psychometric properties were found for the 10-item version of the Modified Weight Bias Internalization Scale. Conclusion The 10-item version of the Modified Weight Bias Internalization Scale surpasses the other versions studied in all psychometric properties. Therefore, it should be used in prebariatric patients to detect weight bias internalization and provide them with psychological interventions that could improve bariatric surgery outcomes.

11.
Eval Health Prof ; 47(1): 3-10, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36898680

RESUMO

The use of coercive practices, i.e., interventions against a person's will, is controversial. Recent observational studies highlighted their potential detrimental effects on patients' mental health, but this topic remains understudied. This study investigated the effect of a common coercive practice, seclusion (i.e., being locked in a closed room), on mental health using a trial emulation of observational data to allow causal inference. We used data from 1200 psychiatric inpatients, classified as being either secluded or non-secluded during their hospital stay. Inverse probability of treatment weighting was used to emulate the random assignment to the intervention. The primary outcome was the Health of the Nations Outcome Scales (HoNOS). The secondary outcome was the first item of the HoNOS, which focuses on overactive, aggressive, disruptive, or agitated behavior. Both outcomes were assessed at hospital discharge. There was a significant effect of seclusion with increases in both total HoNOS score (p = .002) and item 1 of the HoNOS (p = .01). Seclusion may have a negative causal effect of patients' mental health status and should therefore be avoided in mental health care settings. Training efforts should raise the awareness of the medical staff about potential adverse effects instead of therapeutic benefits.


Assuntos
Transtornos Mentais , Humanos , Transtornos Mentais/terapia , Transtornos Mentais/psicologia , Isolamento de Pacientes/psicologia , Pacientes Internados/psicologia , Agressão/psicologia , Nível de Saúde
12.
Curr Neuropharmacol ; 22(4): 736-748, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37888890

RESUMO

We conducted a scientometric analysis to outline clinical research on posttraumatic stress disorder (PTSD). Our primary objective was to perform a broad-ranging scientometric analysis to evaluate key themes and trends over the past decades. Our secondary objective was to measure research network performance. We conducted a systematic search in the Web of Science Core Collection up to 15 August 2022 for publications on PTSD. We identified 42,170 publications published between 1945 and 2022. We used CiteSpace to retrieve the co-cited reference network (1978-2022) that presented significant modularity and mean silhouette scores, indicating highly credible clusters (Q = 0.915, S = 0.795). Four major trends of research were identified: 'war veterans and refugees', 'treatment of PTSD/neuroimaging', 'evidence syntheses', and 'somatic symptoms of PTSD'. The largest cluster of research concerned evidence synthesis for genetic predisposition and environmental exposures leading to PTSD occurrence. Research on war-related trauma has shifted from battlefield-related in-person exposure trauma to drone operator trauma and is being out published by civilian-related trauma research, such as the 'COVID-19' pandemic impact, 'postpartum', and 'grief disorder'. The focus on the most recent trends in the research revealed a burst in the 'treatment of PTSD' with the development of Mhealth, virtual reality, and psychedelic drugs. The collaboration networks reveal a central place for the USA research network, and although relatively isolated, a recent surge of publications from China was found. Compared to other psychiatric disorders, we found a lack of high-quality randomized controlled trials for pharmacological and nonpharmacological treatments. These results can inform funding agencies and future research.


Assuntos
Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Predisposição Genética para Doença
13.
Schizophrenia (Heidelb) ; 9(1): 85, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38071394

RESUMO

Response to antipsychotic medications (AP) is subjected to a wide and unpredictable variability and efforts were directed to discover predictive biomarkers to personalize treatment. Electroencephalography abnormalities in subjects with schizophrenia are well established, as well as a pattern of EEG changes induced by APs. The aim of this review is to provide a synthesis of the EEG features that are related to AP efficacy, including both pre-treatment signatures and changes induced by APs during treatment. A systematic review of English articles using PubMed, PsychINFO and the Cochrane database of systematic reviews was undertaken until july 2023. Additional studies were added by hand search. Studies having as an endpoint the relationship between AP-related clinical improvement and electroencephalographic features were included. Heterogeneity prevented a quantitative synthesis. Out of 1232 records screened, 22 studies were included in a final qualitative synthesis. Included studies evaluated resting-state and task-related power spectra, functional connectivity, microstates and epileptic abnormalities. At pre-treatment resting-state EEG, the most relevant predictors of a poor response were a change in theta power compared to healthy control, a high alpha power and connectivity, and diminished beta power. Considering EEG during treatment, an increased theta power, a reduced beta-band activity, an increased alpha activity, a decreased coherence in theta, alpha and beta-band were related to a favorable outcome. EEG is promising as a method to create a predictive biomarker for response to APs; further investigations are warranted to harmonize and generalize the contradictory results of reviewed studies.

14.
Cerebellum ; 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38151675

RESUMO

Multiple lines of evidence across human functional, lesion, and animal data point to a cerebellar role, in particular of crus I, crus II, and lobule VIIB, in cognitive function. However, a mapping of distinct facets of cognitive function to cerebellar structure is missing. We analyzed structural neuroimaging data from the Healthy Brain Network (HBN). Cerebellar parcellation was performed with a validated automated segmentation pipeline (CERES) and stringent visual quality check (n = 662 subjects retained from initial n = 1452). Canonical correlation analyses (CCA) examined regional gray matter volumetric (GMV) differences in association to cognitive function (quantified with NIH Toolbox Cognition domain, NIH-TB), accounting for psychopathology severity, age, sex, scan location, and intracranial volume. Multivariate CCA uncovered a significant correlation between two components entailing a latent cognitive canonical (NIH-TB subscales) and a brain canonical variate (cerebellar GMV and intracranial volume, ICV), surviving bootstrapping and permutation procedures. The components correspond to partly shared cerebellar-cognitive function relationship with a first map encompassing cognitive flexibility (r = 0.89), speed of processing (r = 0.65), and working memory (r = 0.52) associated with regional GMV in crus II (r = 0.57) and lobule X (r = 0.59) and a second map including the crus I (r = 0.49) and lobule VI (r = 0.49) associated with working memory (r = 0.51). We show evidence for a structural subspecialization of the cerebellum topography for cognitive function in a transdiagnostic sample.

15.
bioRxiv ; 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37961617

RESUMO

Objective: Schizophrenia is a multifaceted disorder associated with structural brain heterogeneity. Despite its relevance for identifying illness subtypes and informative biomarkers, structural brain heterogeneity in schizophrenia remains incompletely understood. Therefore, the objective of this study was to provide a comprehensive insight into the structural brain heterogeneity associated with schizophrenia. Methods: This meta- and mega-analysis investigated the variability of multimodal structural brain measures of white and gray matter in individuals with schizophrenia versus healthy controls. Using the ENIGMA dataset of MRI-based brain measures from 22 international sites with up to 6139 individuals for a given brain measure, we examined variability in cortical thickness, surface area, folding index, subcortical volume and fractional anisotropy. Results: We found that individuals with schizophrenia are distinguished by higher heterogeneity in the frontotemporal network with regard to multimodal structural measures. Moreover, individuals with schizophrenia showed higher homogeneity of the folding index, especially in the left parahippocampal region. Conclusions: Higher multimodal heterogeneity in frontotemporal regions potentially implies different subtypes of schizophrenia that converge on impaired frontotemporal interaction as a core feature of the disorder. Conversely, more homogeneous folding patterns in the left parahippocampal region might signify a consistent characteristic of schizophrenia shared across subtypes. These findings underscore the importance of structural brain variability in advancing our neurobiological understanding of schizophrenia, and aid in identifying illness subtypes as well as informative biomarkers.

16.
Res Sq ; 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37841855

RESUMO

Formal thought disorder (FTD) is a key clinical factor in schizophrenia, but the neurobiological underpinnings remain unclear. In particular, relationship between FTD symptom dimensions and patterns of regional brain volume deficiencies in schizophrenia remain to be established in large cohorts. Even less is known about the cellular basis of FTD. Our study addresses these major obstacles based on a large multi-site cohort through the ENIGMA Schizophrenia Working Group (752 individuals with schizophrenia and 1256 controls), to unravel the neuroanatomy of positive, negative and total FTD in schizophrenia and their cellular bases. We used virtual histology tools to relate brain structural changes associated with FTD to cellular distributions in cortical regions. We identified distinct neural networks for positive and negative FTD. Both networks encompassed fronto-occipito-amygdalar brain regions, but negative FTD showed a relative sparing of orbitofrontal cortical thickness, while positive FTD also affected lateral temporal cortices. Virtual histology identified distinct transcriptomic fingerprints associated for both symptom dimensions. Negative FTD was linked to neuronal and astrocyte fingerprints, while positive FTD was also linked to microglial cell types. These findings relate different dimensions of FTD to distinct brain structural changes and their cellular underpinnings, improve our mechanistic understanding of these key psychotic symptoms.

18.
Schizophr Bull ; 49(6): 1530-1541, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-37606273

RESUMO

BACKGROUND AND HYPOTHESIS: The cholinergic system is altered in schizophrenia. Particularly, patients' volumes of basal-forebrain cholinergic nuclei (BFCN) are lower and correlated with attentional deficits. It is unclear, however, if and how BFCN changes and their link to cognitive symptoms extend across the schizophrenia spectrum, including individuals with at-risk mental state for psychosis (ARMS) or during first psychotic episode (FEP). STUDY DESIGN: To address this question, we assessed voxel-based morphometry (VBM) of structural magnetic resonance imaging data of anterior and posterior BFCN subclusters as well as symptom ratings, including cognitive, positive, and negative symptoms, in a large multi-site dataset (n = 4) comprising 68 ARMS subjects, 98 FEP patients (27 unmedicated and 71 medicated), 140 patients with established schizophrenia (SCZ; medicated), and 169 healthy controls. RESULTS: In SCZ, we found lower VBM measures for the anterior BFCN, which were associated with the anticholinergic burden of medication and correlated with patients' cognitive deficits. In contrast, we found larger VBM measures for the posterior BFCN in FEP, which were driven by unmedicated patients and correlated at-trend with cognitive deficits. We found no BFCN changes in ARMS. Altered VBM measures were not correlated with positive or negative symptoms. CONCLUSIONS: Results demonstrate complex (posterior vs. anterior BFCN) and non-linear (larger vs. lower VBM) differences in BFCN across the schizophrenia spectrum, which are specifically associated both with medication, including its anticholinergic burden, and cognitive symptoms. Data suggest an altered trajectory of BFCN integrity in schizophrenia, influenced by medication and relevant for cognitive symptoms.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológico , Esquizofrenia/patologia , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/tratamento farmacológico , Prosencéfalo , Imageamento por Ressonância Magnética/métodos , Antagonistas Colinérgicos/efeitos adversos , Cognição
19.
Adv Mater ; 35(41): e2305622, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37565798

RESUMO

Terahertz (THz) radiation is a powerful tool with widespread applications ranging from imaging, sensing, and broadband communications to spectroscopy and nonlinear control of materials. Future progress in THz technology depends on the development of efficient, structurally simple THz emitters that can be implemented in advanced miniaturized devices. Here, it is shown how the natural electronic anisotropy of layered conducting transition metal oxides enables the generation of intense terahertz radiation via the transverse thermoelectric effect. In thin films grown on off-cut substrates, femtosecond laser pulses generate ultrafast out-of-plane temperature gradients, which in turn launch in-plane thermoelectric currents, thus allowing efficient emission of the resulting THz field out of the film structure. This scheme is demonstrated in experiments on thin films of the layered metals PdCoO2 and La1.84 Sr0.16 CuO4 , and model calculations that elucidate the influence of the material parameters on the intensity and spectral characteristics of the emitted THz field are presented. Due to its simplicity, the method opens up a promising avenue for the development of highly versatile THz sources and integrable emitter elements.

20.
Front Psychiatry ; 14: 1224328, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37636826

RESUMO

Background: Coercion is one of the most important challenges in mental health. In Switzerland, forced medication can be applied during an emergency (Art. 435 of the Civil Code) or over a longer period in case of endangerment of others or oneself (Art. 434). We aimed to analyze the predictors of this specific treatment without consent. Methods: Forced medication prescriptions in the Division of Adult Psychiatry of the Geneva University Hospitals between 2018 and 2021 were retrospectively analyzed. Medication under Article 434 was the main outcome variable. Age, gender, admission mode, main diagnosis, and the Health of the Nation Outcome Scales (HoNOS) score at admission were considered as potential predictors. T-test and Pearson's chi-square test were used to compare continuous and categorical variables. A logistic regression was performed to find significant predictors of forced medication. Results: Seventy-one out of 4,326 inpatients were subjected to forced medication under Art. 434. HoNOS global scores at admission were not significantly different in the forced medication group compared to the control group. Aggressive behavior was lower in the former at the univariate level. Forced medication was associated at the multivariate level with female gender, involuntary admission, and psychosis. Conclusion: Women suffering from psychosis are more at risk of receiving involuntary and repeated medication. The risk of deterioration in psychosocial functioning or behavioral disorganization seems to be the main argument for this coercive measure. Future studies should focus on the patient's perception of this coercion to prevent it and improve adherence to care. Follow-up after discharge might be useful to evaluate a long-term benefit.

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