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Background Brain magnetic resonance imaging studies have not investigated the cortical surface comprehensively in schizophrenia subjects by assessing thickness, surface area and gyrification separately during the first-episode of psychosis (FEP) or chronic schizophrenia (ChSch). Methods We investigated cortical surface abnormalities in 137 FEP patients and 240 ChSch subjects compared to 297 Healthy Controls (HC) contributed by five cohorts. Maps showing results of vertexwise between-group comparisons of cortical thickness, area, and gyrification were produced using T1-weighted datasets processed using FreeSurfer 5.3, followed by validated quality control protocols. Results FEP subjects showed large clusters of increased area and gyrification relative to HC in prefrontal and insuli cortices (Cohen's d: 0.049 to 0.28). These between-group differences occurred partially beyond the effect of sample. ChSch subjects displayed reduced cortical thickness relative to HC in smaller fronto-temporal foci (d: −0.73 to −0.35), but not beyond the effect of sample. Differences between FEP and HC subjects were associated with male gender, younger age, and earlier illness onset, while differences between ChSch and HC were associated with treatment-resistance and first-generation antipsychotic (FGA) intake independently of sample effect. Conclusions Separate assessments of FEP and ChSch revealed abnormalities that differed in regional distribution, phenotypes affected and effect size. In FEP, associations of greater cortical area and gyrification abnormalities with earlier age of onset suggest an origin on anomalous neurodevelopment, while thickness reductions in ChSch are at least partially explained by treatment-resistance and FGA intake. Associations of between-group differences with clinical variables retained statistical significance beyond the effect of sample.

Objective: People with Alzheimer’s disease (AD) dementia have impaired sleep. However, the characteristics of sleep in the early stages of AD are not well known, and studies with the aid of biomarkers are lacking. We assessed the subjective sleep characteristics of non-demented older adults and compared their amyloid profiles. Methods: We enrolled 30 participants aged ≥ 60 years, with no dementia or major clinical and psychiatric diseases. They underwent [11C]PiB-PET-CT, neuropsychological evaluations, and completed two standardized sleep assessments (Pittsburgh Sleep Quality Inventory and Epworth Sleep Scale). Results: Comparative analysis of subjective sleep parameters across the two groups showed longer times in bed (p = 0.024) and reduced sleep efficiency (p = 0.05) in individuals with positive amyloid. No differences in other subjective sleep parameters were observed. We also found that people with multiple-domain mild cognitive impairment (MCI) had shorter self-reported total sleep times (p = 0.034) and worse overall sleep quality (p = 0.027) compared to those with single-domain MCI. Conclusions: Older adults testing positive for amyloid had a longer time in bed and lower sleep efficiency, regardless of cognitive status. In parallel, individuals with multiple-domain MCI reported shorter sleep duration and lower overall sleep quality.

Background Cannabidiol (CBD) is a non-intoxicating substance present in the extract of Cannabis sativa popularised by its therapeutic potential. A limited number of neuroimaging studies have investigated CBD effects on brain function primarily in healthy individuals, people with early/ clinical high risk of psychosis, and social anxiety disorder. As a result of heterogeneity in the population examined, imaging modality and neurocognitive paradigm, the acute brain effects of CBD and the molecular mechanisms that may underlie its effects remain unclear. Methods We meta-analysed neuroimaging studies that examined the acute effects of CBD, relative to placebo, on human brain function using SPECT and fMRI while performing diverse cognitive tasks. Subsequently, we examined the relationship between the spatially distributed pooled effects of CBD on brain signal and the distribution of candidate mechanistic targets for the effects of CBD including fatty acid amide hydrolase (FAAH), dopamine D2, serotonin and cannabinoid-type-1 receptors as indexed by their gene expression data. Results CBD modulated the function of several brain regions, including the medial frontoparietal, midcingulo-insular, pericentral, lateral frontoparietal, and dorsal frontoparietal networks as well as the striatum and cerebellum. There was a significant inverse relationship between the magnitude of pooled CBD effect on brain activation and expression of FAAH but not the other targets. Discussion These preliminary findings suggest that the effect of CBD in the human brain may be linked to local FAAH availability and suggests that there is a strong case for directly examining whether the effects of CBD on FAAH underlie its effects on brain function and behaviour.

Objective: Positron emission tomography (PET) allows in vivo evaluation of molecular targets in neurodegenerative diseases, such as Alzheimer’s disease. Mild cognitive impairment is an intermediate stage between normal cognition and Alzheimer-type dementia. In vivo fibrillar amyloid-beta can be detected in PET using [11C]-labeled Pittsburgh compound B (11C-PiB). In contrast, [18F]fluoro-2-deoxy-d-glucose (18F-FDG) is a neurodegeneration biomarker used to evaluate cerebral glucose metabolism, indicating neuronal injury and synaptic dysfunction. In addition, early cerebral uptake of amyloid-PET tracers can determine regional cerebral blood flow. The present study compared early-phase 11C-PiB and 18F-FDG in older adults without cognitive impairment, amnestic mild cognitive impairment, and clinical diagnosis of probable Alzheimer’s disease. Methods: We selected 90 older adults, clinically classified as healthy controls, with amnestic mild cognitive impairment, or with probable Alzheimer’s disease, who underwent an 18F-FDG PET, early-phase 11C-PiB PET and magnetic resonance imaging. All participants were also classified as amyloid-positive or -negative in late-phase 11C-PiB. The data were analyzed using statistical parametric mapping. Results: We found that the probable Alzheimer’s disease and amnestic mild cognitive impairment group had lower early-phase 11C-PiB uptake in limbic structures than 18F-FDG uptake. The images showed significant interactions between amyloid-beta status (negative or positive). However, early-phase 11C-PiB appears to provide different information from 18F-FDG about neurodegeneration. Conclusions: Our study suggests that early-phase 11C-PiB uptake correlates with 18F-FDG, irrespective of the particular amyloid-beta status. In addition, we observed distinct regional distribution patterns between both biomarkers, reinforcing the need for more robust studies to investigate the real clinical value of early-phase amyloid-PET imaging.

Purpose: The aim of this study was to describe the incidence and risk factors for hospital readmission and infection during the months after COVID-19 hospital admission. Methods: This prospective study included adult patients who were hospitalized due to COVID-19 and had been discharged from April 2020 to August 2020. All patients had a medical evaluation with a structured questionnaire 6 to 11 months after hospital admission. The authors included only patients with confirmed COVID-19 by RT-PCR. Patients with pregnant/postpartum women, with a proven COVID-19 reinfection or incapable of answering the questionnaire were excluded. Results: A total of 822 patients completed the follow-up assessment, and 68% reportedat least one recurrent symptom related to COVID-19. The most frequent symptom was myalgia (42%). Thirty-two percent of patients visited an emergency room after COVID-19 hospitalization, and 80 (10%) patients required re-hospitalization. Risk factors for hospital readmission were orotracheal intubation during COVID-19 hospitalization (p = 0.003, OR = 2.14), Charlson score (p = 0.002, OR = 1.21), congestive heart failure (p = 0.005, OR = 2.34), peripheral artery disease (p = 0.06, OR= 2.06) and persistent diarrhea after COVID-19 hospitalization discharge (p= 0.02, OR = 1.91). The main cause of hospital readmission was an infection, 43 (54%). Pneumonia was the most frequent infection (29%). Conclusions: The presence of symptoms after six months of COVID-19 diagnosis was frequent, and hospital readmission was relatively high. HIGHLIGHTS 32% of the patients visited an emergency room after COVID-19 hospitalization. The rate of hospital readmission after COVID-19 hospitalization is high, in the present sample 10% of patients needed a second hospitalization in 6-months Patients with persistent diarrhea after COVID-19 discharge had two times more chance to have another hospitalization in the next 6-months.

Background: Previous studies of hippocampal function and volume related to episodic memory deficits in patients with amnestic mild cognitive impairment (aMCI) have produced mixed results including increased or decreased activity and volume. However, most of them have not included biomarkers, such as amyloid-β (Aβ) deposition which is the hallmark for early identification of the Alzheimer’s disease continuum. Objective: We investigated the role of Aβ deposition, functional hippocampal activity and structural volume in aMCI patients and healthy elderly controls (HC) using a new functional MRI (fMRI) ecological episodic memory task. Methods: Forty-six older adults were included, among them Aβ PET PIB positive (PIB+) aMCI (N = 17), Aβ PET PIB negative (PIB–) aMCI (N = 15), and HC (N = 14). Hippocampal volume and function were analyzed using Freesurfer v6.0 and FSL for news headlines episodic memory fMRI task, and logistic regression for group classification in conjunction with episodic memory task and traditional neuropsychological tests. Results: The aMCI PIB+ and PIB–patients showed significantly worse performance in relation to HC in most traditional neuropsychological tests and within group difference only on story recall and the ecological episodic memory fMRI task delayed recall. The classification model reached a significant accuracy (78%) and the classification pattern characterizing the PIB+ included decreased left hippocampal function and volume, increased right hippocampal function and volume, and worse episodic memory performance differing from PIB–which showed increased left hippocampus volume. Conclusion: The main findings showed differential neural correlates, hippocampal volume and function during episodic memory in aMCI patients with the presence of Aβ deposition.

BackgroundMajor depressive disorder (MDD) is associated with an increased risk of brain atrophy, aging-related diseases, and mortality. We examined potential advanced brain aging in MDD patients, and whether this process is associated with clinical characteristics in a large multi-center international dataset.MethodsWe performed a mega-analysis by pooling brain measures derived from T1-weighted MRI scans from 29 samples worldwide. Normative brain aging was estimated by predicting chronological age (10-75 years) from 7 subcortical volumes, 34 cortical thickness and 34 surface area, lateral ventricles and total intracranial volume measures separately in 1,147 male and 1,386 female controls from the ENIGMA MDD working group. The learned model parameters were applied to 1,089 male controls and 1,167 depressed males, and 1,326 female controls and 2,044 depressed females to obtain independent unbiased brain-based age predictions. The difference between predicted “brain age” and chronological age was calculated to indicate brain predicted age difference (brain-PAD).FindingsOn average, MDD patients showed a higher brain-PAD of +0.90 (SE 0.21) years (Cohen’s d=0.12, 95% CI 0.06-0.17) compared to controls. Relative to controls, first-episode and currently depressed patients showed higher brain-PAD (+1.2 [0.3] years), and the largest effect was observed in those with late-onset depression (+1.7 [0.7] years). In addition, higher brain-PAD was associated with higher self-reported depressive symptomatology (b=0.05, p=0.004).InterpretationThis highly powered collaborative effort showed subtle patterns of abnormal structural brain aging in MDD. Substantial within-group variance and overlap between groups were observed. Longitudinal studies of MDD and somatic health outcomes are needed to further assess the predictive value of these brain-PAD estimates.FundingThis work was supported, in part, by NIH grants U54 EB020403 and R01 MH116147.

To evaluate color vision changes and retinal processing of chromatic and luminance pathways in subjects with Alzheimer disease (AD) and mild cognitive impairment (MCI) compared with a matched control group and whether such changes are associated with impaired brain glucose metabolism and β-amyloid deposition in the brain.We evaluated 13 patients with AD (72.4 ± 7.7 years), 23 patients with MCI (72.5 ± 5.5 years), and 18 controls of comparable age (P = 0.44) using Cambridge color test and the heterochromatic flicker ERG (HF-ERG). The Cambridge color test was performed using the trivector protocol to estimate the protan, deutan and tritan color confusion axes. HF-ERG responses were measured at a frequency of 12 Hz, which ERGs reflect chromatic activity, and at 36 Hz, reflecting luminance pathway. A study subsample was performed using neuropsychological assessments and positron emission tomography.Patients with AD presented higher mean values indicating poorer color discrimination for protan (P = 0.04) and deutan (P = 0.001) axes compared with the controls. Along the tritan axis, both patients with AD and patients with MCI showed decreased color vision (P = 0.001 and P = 0.001) compared with controls. The analyses from the HF-ERG protocol revealed no differences between the groups (P = 0.31 and P = 0.41). Diffuse color vision loss was found in individuals with signs of neurodegeneration (protan P = 0.002, deutan P = 0.003 and tritan P = 0.01), but not in individuals with signs of β-amyloid deposition only (protan P = 0.39, deutan P = 0.48, tritan P = 0.63), regardless of their clinical classification.Here, patients with AD and patients with MCI present acquired color vision deficiency that may be linked with impaired brain metabolism.

BackgroundPositive symptoms are a useful predictor of aggression in schizophrenia. Although a similar pattern of abnormal brain structures related to both positive symptoms and aggression has been reported, this observation has not yet been confirmed in a single sample.MethodTo study the association between positive symptoms and aggression in schizophrenia on a neurobiological level, a prospective meta-analytic approach was employed to analyze harmonized structural neuroimaging data from 10 research centers worldwide. We analyzed brain MRI scans from 902 individuals with a primary diagnosis of schizophrenia and 952 healthy controls.ResultsThe result identified a widespread cortical thickness reduction in schizophrenia compared to their controls. Two separate meta-regression analyses revealed that a common pattern of reduced cortical gray matter thickness within the left lateral temporal lobe and right midcingulate cortex was significantly associated with both positive symptoms and aggression.ConclusionThese findings suggested that positive symptoms such as formal thought disorder and auditory misperception, combined with cognitive impairments reflecting difficulties in deploying an adaptive control toward perceived threats, could escalate the likelihood of aggression in schizophrenia.

An early and persistent sign of Alzheimer’s disease (AD) is glucose hypometabolism, which can be evaluated by positron emission tomography (PET) with 18F-2-fluoro-2-deoxy-D-glucose ([18F]FDG). Cannabidiol has demonstrated neuroprotective and anti-inflammatory properties but has not been evaluated by PET imaging in an AD model. Intracerebroventricular (icv) injection of streptozotocin (STZ) is a validated model for hypometabolism observed in AD. This proof-of-concept study evaluated the effect of cannabidiol treatment in the brain glucose metabolism of an icv-STZ AD model by PET imaging. Wistar male rats received 3 mg/kg of STZ and [18F]FDG PET images were acquired before and 7 days after STZ injection. Animals were treated with intraperitoneal cannabidiol (20 mg/kg—STZ–cannabidiol) or saline (STZ–saline) for one week. Novel object recognition was performed to evaluate short-term and long-term memory. [18F]FDG uptake in the whole brain was significantly lower in the STZ–saline group. Voxel-based analysis revealed a hypometabolism cluster close to the lateral ventricle, which was smaller in STZ–cannabidiol animals. The brain regions with more evident hypometabolism were the striatum, motor cortex, hippocampus, and thalamus, which was not observed in STZ–cannabidiol animals. In addition, STZ–cannabidiol animals revealed no changes in memory index. Thus, this study suggests that cannabidiol could be an early treatment for the neurodegenerative process observed in AD.

The neurobiological mechanisms underlying the effects of delta-9-tetrahydrocannabinol (THC) remain unclear. Here, we examined the spatial acute effect of THC on human regional brain activation or blood flow (hereafter called 'activation signal') in a 'core' network of brain regions from 372 participants, tested using a within-subject repeated measures design under experimental conditions. We also investigated whether the neuromodulatory effects of THC are related to the local expression of the cannabinoid-type-1 (CB1R) and type-2 (CB2R) receptors. Finally, we investigated the dose-response relationship between THC and key brain substrates. These meta-analytic findings shed new light on the localisation of the effects of THC in the human brain, suggesting that THC has neuromodulatory effects in regions central to many cognitive tasks and processes, related to dose, with greater effects in regions with higher levels of CB1R expression.

Importance: Owing to its anti-inflammatory properties and antiviral “in vitro” effect against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), cannabidiol (CBD) has been proposed as a ...

Special Issue: The ENIGMA Consortium: the first 10 years., Schizophrenia is associated with widespread alterations in subcortical brain structure. While analytic methods have enabled more detailed morphometric characterization, findings are often equivocal. In this meta-analysis, we employed the harmonized ENIGMA shape analysis protocols to collaboratively investigate subcortical brain structure shape differences between individuals with schizophrenia and healthy control participants. The study analyzed data from 2,833 individuals with schizophrenia and 3,929 healthy control participants contributed by 21 worldwide research groups participating in the ENIGMA Schizophrenia Working Group. Harmonized shape analysis protocols were applied to each site's data independently for bilateral hippocampus, amygdala, caudate, accumbens, putamen, pallidum, and thalamus obtained from T1-weighted structural MRI scans. Mass univariate meta-analyses revealed more-concave-than-convex shape differences in the hippocampus, amygdala, accumbens, and thalamus in individuals with schizophrenia compared with control participants, more-convex-than-concave shape differences in the putamen and pallidum, and both concave and convex shape differences in the caudate. Patterns of exaggerated asymmetry were observed across the hippocampus, amygdala, and thalamus in individuals with schizophrenia compared to control participants, while diminished asymmetry encompassed ventral striatum and ventral and dorsal thalamus. Our analyses also revealed that higher chlorpromazine dose equivalents and increased positive symptom levels were associated with patterns of contiguous convex shape differences across multiple subcortical structures. Findings from our shape meta-analysis suggest that common neurobiological mechanisms may contribute to gray matter reduction across multiple subcortical regions, thus enhancing our understanding of the nature of network disorganization in schizophrenia., Center for Integrated Healthcare, U.S. Department of Veterans Affairs, Grant/Award Number: I01 CX000497; Commonwealth Health Research Board, Grant/Award Number: HRA_POR/2011/100; Conselho Nacional de Desenvolvimento Científico e Tecnológico, Grant/Award Numbers: 478466/2009, 480370/2009; Department of Energy, Labor and Economic Growth, Grant/Award Number: DE-FG02-99ER62764; Forskningsrådet om Hälsa, Arbetsliv och Välfärd, Grant/Award Numbers: K2009-62X-15077-06-3, K2012-61X-15077-09-3, 523-2014-3467, 2009-7053, 2013-2838; Fundação Amazônia Paraense de Amparo à Pesquisa, Grant/Award Numbers: 2009/14891-9, 2010/18672-7, 2012/23796-2, 2013/039; Instituto de Salud Carlos III, Grant/Award Numbers: FIS 00/3095, 01/3129, PI020499, PI060507, PI10/001; National Health and Medical Research Council, Grant/Award Numbers: 1009064, 496682; National Institutes of Health, Grant/Award Numbers: 1RC1MH089257, MH 60722, MH019112, MH064045, MH085096, MH098130, MO1 RR025758, P41RR14075, P50 MH071616, R01 DA053028, R01 EB020062, R01 HD050735, R01 MH056584, R01 MH084803, R01 MH116147, R01 MH117601, R01EB005846, R01EB015611, R01MH074797, R21 MH097196, R21MH097196, R37MH43375, S10 OD023696, T32 AG058507, T32 MH073526, TR000153, U01 MH097435, U24 RR021382A, U24 RR021992, U24 RR025736, U24 RR21992, U24RR021992, U54 EB020403, U54EB020403, UL1 TR000153; National Science Foundation, Grant/Award Numbers: 1636893, 1734853; Norges Forskningsråd, Grant/Award Numbers: 213837, 217776, 223273; Science Foundation Ireland, Grant/Award Numbers: 08/IN.1/B1916, 12/IP/1359; Wellcome Trust, Grant/Award Number: 072894/2/03/Z.

Altered structural brain asymmetry in autism spectrum disorder (ASD) has been reported. However, findings have been inconsistent, likely due to limited sample sizes. Here we investigated 1,774 individuals with ASD and 1,809 controls, from 54 independent data sets of the ENIGMA consortium. ASD was significantly associated with alterations of cortical thickness asymmetry in mostly medial frontal, orbitofrontal, cingulate and inferior temporal areas, and also with asymmetry of orbitofrontal surface area. These differences generally involved reduced asymmetry in individuals with ASD compared to controls. Furthermore, putamen volume asymmetry was significantly increased in ASD. The largest case-control effect size was Cohen's d = -0.13, for asymmetry of superior frontal cortical thickness. Most effects did not depend on age, sex, IQ, severity or medication use. Altered lateralized neurodevelopment may therefore be a feature of ASD, affecting widespread brain regions with diverse functions. Large-scale analysis was necessary to quantify subtle alterations of brain structural asymmetry in ASD.

Impaired glucose metabolism reflects neuronal/synaptic dysfunction and cognitive function decline in patients with obstructive sleep apnea (OSA). The study investigated the extent to which exercise training (ET) improves cerebral metabolic glucose rate (CMRgl) and cognitive function in patients with OSA. Patients with moderate to severe OSA were randomly assigned to ET (3 times/week, n = 23) or no intervention (control, n = 24). Echocardiography and apolipoprotein ε4 (APOEε4) genotyping were obtained at baseline. Both groups underwent cardiopulmonary exercise testing, polysomnography, cognitive tests, brain magnetic resonance imaging, and 18F-fluoro-2-deoxy-d-Glucose positron emission tomography (18FDG-PET) at baseline and study end. Compared with control, exercise-trained group had improved exercise capacity, decreased apnea–hypopnea index (AHI), oxygen desaturation and arousal index; increased attention/executive functioning, increased CMRgl in the right frontal lobe (P P P 2 saturation during sleep and non-rapid eye movement sleep (r = − 0.43, P P P Trial registration: NCT02289625 (13/11/2014).

Approximately 10% of adolescents worldwide are overweight or obese, hence the urgent and universal need to elucidate possible mechanisms that lead to obesity in the adolescent population.We examined the hypothalamic metabolism and its relationship with physical development in obese and eutrophic adolescents.We performed a case-control study with 115 adolescents between 11 and 18 years of age, to compare obese (BMI z-score ≥ 2) and nonobese individuals (eutrophic controls; BMI z-score ≤ 1). The following hypothalamic metabolite ratios were examined as primary outcomes: glutamate/creatine (Cr), the sum of glutamate and glutamine/Cr, N-acetylaspartate (NAA)/Cr, myoinositol/Cr, and total choline/Cr (glycerophosphocholine + phosphocholine/Cr), quantified by magnetic resonance spectroscopy. BMI z-scores, pubertal status, and scores on the Yale Food Addiction Scale, the Binge Eating Scale, and the Child Depression Inventory were assessed as secondary outcomes. Pearson coefficients (r) or nonparametric Spearman correlation (rho) analyses were performed between hypothalamic metabolite ratios and other parameters, such as BMI z-scores, physical development, food habits, depression symptoms, and serum protein concentrations (cytokines, hormones, and neuropeptides).Adolescents with obesity showed a lower hypothalamic NAA/Cr ratio (0.70 ± 0.19) compared to their eutrophic counterparts (0.84 ± 0.20; P = 0.004). The NAA/Cr ratio was negatively correlated with BMI z-scores (r = -0.25; P = 0.03) and serum insulin (rho = -0.27; P = 0.04), C-peptide (rho = -0.26; P = 0.04), amylin (r = -0.27; P = 0.04), ghrelin (rho = -0.30; P = 0.02), and neuropeptide Y (r = -0.27; P = 0.04). Also, the NAA/Cr ratio was positively correlated with circulating IL-8 levels (rho = 0.26; P = 0.04).High BMI z-scores are associated with lower hypothalamic NAA/Cr ratios. The negative correlations found between the NAA/Cr ratio and serum cytokines, hormones, and neuropeptides suggest a broad cross-talk linking hormonal imbalances, neurohumoral alterations, and hypothalamic functions in adolescents with obesity.

Background: Multiple sclerosis (MS) is a demyelinating and inflammatory disease of the central nervous system. Its diagnosis is clinical, often confirmed by magnetic resonance imaging. This image modality, however, is not ideal for discrimination of demyelination in grey and white matter regions from inflammatory lesions. Positron Emission Tomography (PET), using specific radiopharmaceuticals, can be a tool to differentiate between these processes. The radiopharmaceutical [C-11]PIB is widely used for detection of beta-amyloid plaques, but has also been suggested for the analysis of myelin content due to its consistent uptake in white matter. The aim of this study was to evaluate [C-11]PIB PET imaging as a tool for detecting demyelinated regions in white and grey matter of non-human primate model of progressive MS.Methods: Experimental autoimmune encephalomyelitis (EAE) was induced in marmosets by injection of re-combinant human myelin oligodendrocyte glycoprotein (rhMOG) emulsified in either Incomplete Freund's Adjuvant (IFA) or Complete Freund's Adjuvant (CFA). [C-11]PIB PET images were acquired prior to immunization (baseline) and after symptoms were present (end of experiment). Brain tissue was isolated for histochemical analysis.Results: All rhMOG/IFA-treated and rhMOG/CFA-treated animals showed clinical signs of EAE. The rhMOG/CFA group presented a significant [C-11]PIB uptake reduction only in the left motor cortex (9%, P = 0.011). For the rhMOG/IFA group, significant decrease in [C-11]PIB uptake was observed in the whole brain (15%, P = 0.015), in the right hemisphere of body of corpus callosum (34%, P = 0.02), splenium of corpus callosum (38%, P = 0.004), hippocampus (19%, P = 0.036), optic tract (13%, P = 0.025), thalamus (14%, P = 0.041), Globus pallidus (23%, P = 0.017), head of caudate nucleus (25%, P = 0.045), tail of caudate nucleus (29%, P = 0.003), putamen (28%, P = 0.047) and left hemisphere of body of corpus callosum (14%, P = 0.037) and head of caudate nucleus (23%, P = 0.023). [C-11]PIB uptake significantly correlated with luxol fast blue histology (myelin marker), both in the rhMOG/IFA (r(2) = 0.32, P Conclusion: [C-11]PIB PET imaging is an efficient tool for detecting demyelination in grey and white matter, in a non-human primate model of progressive MS.

Background Post-stroke depression (PSD) and cognitive impairment (PCI) are common conditions. This study aims to describe the protocol and preliminary findings of an investigation into factors associated with PSD and PCI 1–3 months after stroke (subacute phase) in survivors from the Study of Stroke Mortality and Morbidity (EMMA study). Methods Stroke patients underwent to clinical and neurological evaluations on admission to hospital. Cerebral magnetic resonance and biomarkers (serotonin, BDNF, IL-6 and IL-18) were carried out in the subacute phase. DSM-IV major depression for the diagnosis of PSD, cognitive functioning for the diagnosis of PCI and functional disability were also recorded at same time. Results Of the 103 eligible patients, 85.4% had ischemic stroke and 73.7% had first-ever stroke. In the subacute phase, 27.2% had PCI and 13.6% had current PSD (5.8% with ‘first episode’ and 7.8% with ‘recurrent’ depression). PCI was associated with low education (0–7 years of formal education: 75%) and ageing (median age: 70; interquartile range: 59–75 y-old). Left-sided stroke was more frequently associated with increased PCI than right-sided stroke (71.4% vs. 28.4%, p = 0.005). PSD was neither associated with stroke laterality nor tentorial area. Overall, biomarkers levels were not alterated in patients with PSD and PCI. Limitations Findings are based on small sample and less disabled stroke participants, e.g. those without aphasia and deafness. Conclusions Findings reinforce the need of early recognition and rehabilitation of PCI and PSD, mainly among those less educated and with left-sided stroke. PSD might occur through a pathophysiological pathway other than classical depression.

Background: According to the recent NIA-AA, a probable predictor of Alzheimer’s disease convertor in mild cognitive impairment (MCI) is the Aβ protein deposit in PET PIB exam. However, there is a lack of studies investigating functional connectivity in PIB +/- MCI patients. Objectives: to investigate differences in functional connectivity during resting state in MCI patients with PET PIB+ and - biomarkers. Methods: PET PIB+ (N=12 and PIB- (N=12) MCI patients underwent fMRI during resting state using 3 ROIS related to memory (posterior cingulate and bilateral hippocampus). Results: there were significant connectivity differences (p

Background: Visual atrophy scales from the medial temporal region are auxiliary biomarker methods in Alzheimer’s Disease(AD).They may correlated with progression from preclinical to clinical AD. Objective: We aimed to compare medial temporal lobe atrophy (MTA) and entorhinal cortex atrophy (ERICA) scales for magnetic resonance image as a useful tool for probable AD diagnosis and evaluate their accuracy, sensitivity and specificity, regarding clinical diagnosis and 11C-PIB-PET. Methods: 2 neurologists blinded to diagnosis classified 113 adults (over 65y) through MTA and ERICA scales and correlated with sociodemographic data, amyloid brain cortical burden through the 11C-PIB-PET and clinical cognitive status, divided into 30 cognitive unimpaired (CU) individuals, 52 MCI and 31 dementia compatible with AD (DCAD). Results: Inter-rater reliability of these atrophy scales was excellent (0.8- 1) by Cohen analysis. CU group had significantly lower MTA scores (median value 0) than ERICA (median value 1)for both hemispheres. 11C-PIB-PET was positive in 45% of the whole sample. In MCI and DCAD groups, ERICA depicted greater sensitivity and MTA greater specificity. Accuracy was under 70% for both scores in all clinical groups. Conclusion: Our study achieved a moderate sensitivity for ERICA score and could be a better screening tool for DCAD or MCI than MTA score. But, none of them could be considered a useful biomarker in preclinical AD.

The last four decades have witnessed tremendous growth in research studies applying neuroimaging methods to evaluate pathophysiological and treatment aspects of psychiatric disorders around the world. This article provides a brief history of psychiatric neuroimaging research in Brazil, including quantitative information about the growth of this field in the country over the past 20 years. Also described are the various methodologies used, the wealth of scientific questions investigated, and the strength of international collaborations established. Finally, examples of the many methodological advances that have emerged in the field of in vivo neuroimaging are provided, with discussion of the challenges faced by psychiatric research groups in Brazil, a country of limited resources, to continue incorporating such innovations to generate novel scientific data of local and global relevance.

Clinical characteristics of COVID-19 SARS-CoV-2 may remain viable in the environment for up to 72 hours (). Besides, an infected respiratory droplet can spread viral loads in the environment up to 2 meters from where it is generated through coughing, sneezing, or speaking. In this manner, COVID-19 is acquired either by inhaling droplets or touching a contaminated surface and then touching the nose, mouth, or eyes. An infected patient usually transmits the disease for an average period of 7 days [...]

Changes in hippocampal subfield volumes (HSV) along the Alzheimer's disease (AD) continuum have been scarcely investigated to date in elderly subjects classified based on the presence of β-amyloid aggregation and signs of neurodegeneration. We classified patients (either sex) with mild dementia compatible with AD (n = 35) or amnestic mild cognitive impairment (n = 39), and cognitively unimpaired subjects (either sex; n = 26) using [11 C]PIB-PET to assess β-amyloid aggregation (A+) and [18 F]FDG-PET to account for neurodegeneration ((N)+). Magnetic resonance imaging-based automated methods were used for HSV and white matter hyperintensity (WMH) measurements. Significant HSV reductions were found in A+(N)+ subjects in the presubiculum/subiculum complex and molecular layer, related to worse memory performance. In both the A+(N)+ and A+(N)- categories, subicular volumes were inversely correlated with the degree of Aβ deposition. The A-(N)+ subgroup showed reduced HSV relative to the A-(N)- subgroup also in the subiculum/presubiculum. Combining all (N)- subjects, HSV were lower in subjects presenting significant cognitive decline irrespective of A+/A- classification (controlling for WMH load); these between-group differences were detected again in the presubiculum, but also involved the CA4 and granular layer. These findings demonstrate that differential HSV reductions are detectable both in (N)+ and (N)- categories along the AD continuum, and are directly related to the severity of cognitive deficits. HSV reductions are larger both in A+(N)+ and A+(N)- subjects in direct proportion to the degree of Aβ deposition. The meaningful HSV reductions detected in the A-(N)+ subgroup highlights the strength of biomarker-based classifications outside of the classical AD continuum.

COVID-19 may lead to persistent and potentially incapacitating clinical manifestations (post-acute sequelae of SARS-CoV-2 infection (PASC)). Using easy-to-apply questionnaires and scales (often by telephone interviewing), several studies evaluated samples of COVID-19 inpatients from 4 weeks to several months after discharge. However, studies conducting systematic multidisciplinary assessments of PASC manifestations are scarce, with thorough in-person objective evaluations restricted to modestly sized subsamples presenting greatest disease severity.We will conduct a prospective observational study of surviving individuals (above 18 years of age) from a cohort of over 3000 subjects with laboratory-confirmed COVID-19 who were treated as inpatients at the largest academic health centre in Sao Paulo, Brazil (Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo). All eligible subjects will be consecutively invited to undergo a 1-2-day series of multidisciplinary assessments at 2 time-points, respectively, at 6-9 months and 12-15 months after discharge. Assessment schedules will include detailed multidomain questionnaires applied by medical research staff, self-report scales, objective evaluations of cardiopulmonary functioning, physical functionality and olfactory status, standardised neurological, psychiatric and cognitive examinations, as well as diagnostic laboratory, muscle ultrasound and chest imaging exams. Remaining material from blood tests will be incorporated by a local biobank for use in future investigations on inflammatory markers, genomics, transcriptomics, peptidomics and metabolomics.All components of this programme have been approved by local research ethics committees. We aim to provide insights into the frequency and severity of chronic/post-COVID multiorgan symptoms, as well as their interrelationships and associations with acute disease features, sociodemographic variables and environmental exposures. Findings will be disseminated in peer-reviewed journals and at scientific meetings. Additionally, we aim to provide a data repository to allow future pathophysiological investigations relating clinical PASC features to biomarker data extracted from blood samples.RBR-8z7v5wc; Pre-results.

Objective: Asymmetry is a subtle but pervasive aspect of the human brain, and it may be altered in several psychiatric conditions. MRI studies have shown subtle differences of brain anatomy between people with major depressive disorder and healthy control subjects, but few studies have specifically examined brain anatomical asymmetry in relation to this disorder, and results from those studies have remained inconclusive. At the functional level, some electroencephalography studies have indicated left fronto-cortical hypoactivity and right parietal hypoactivity in depressive disorders, so aspects of lateralized anatomy may also be affected. The authors used pooled individual-level data from data sets collected around the world to investigate differences in laterality in measures of cortical thickness, cortical surface area, and subcortical volume between individuals with major depression and healthy control subjects.Methods: The authors investigated differences in the laterality of thickness and surface area measures of 34 cerebral cortical regions in 2,256 individuals with major depression and 3,504 control subjects from 31 separate data sets, and they investigated volume asymmetries of eight subcortical structures in 2,540 individuals with major depression and 4,230 control subjects from 32 data sets. T-1-weighted MRI data were processedwith a single protocol using FreeSurfer and the Desikan-Killiany atlas. The large sample size provided 80% power to detect effects of the order of Cohen's d=0.1.Results: The largest effect size (Cohen's d) of major depression diagnosis was 0.085 for the thickness asymmetry of the superior temporal cortex, which was not significant after adjustment for multiple testing. Asymmetry measures were not significantly associated with medication use, acute compared with remitted status, first episode compared with recurrent status, or age at onset.Conclusions: Altered brain macro-anatomical asymmetry may be of little relevance to major depression etiology in most cases.

We organized 10Kin1day, a pop-up scientific event with the goal to bring together neuroimaging groups from around the world to jointly analyze 10,000+ existing MRI connectivity datasets during a 3-day workshop. In this report, we describe the motivation and principles of 10Kin1day, together with a public release of 8,000+ MRI connectome maps of the human brain. Ongoing grand-scale projects like the European Human Brain Project (1), the US Brain Initiative (2), the Human Connectome Project (3), the Chinese Brainnetome (4) and exciting world-wide neuroimaging collaborations such as ENIGMA (5) herald the new era of big neuroscience. In conjunction with these major undertakings, there is an emerging trend for bottom-up initiatives, starting with small-scale projects built upon existing collaborations and infrastructures. As described by Mainen et al. (6), these initiatives are centralized around self-organized groups of researchers working on the same challenges and sharing interests and specialized expertise. These projects could scale and open up to a larger audience and other disciplines over time, eventually lining up and merging their findings with other programs to make the bigger picture., The 10Kin1day workshop was generously sponsored by the Neuroscience and Cognition program Utrecht (NCU) of the Utrecht University (https://www.uu.nl/en/research/ neuroscience-and-cognition-utrecht), the ENIGMA consortium (http://enigma.ini.usc.edu), and personal grants: MvdH: NWOVIDI (452-16-015), MQ Fellowship; SB-C: the Wellcome Trust; Medical Research Council UK; NIHR CLAHRC for Cambridgeshire and Peterborough Foundation National Health Services Trust; Autism Research Trust; LB: New Investigator Award, Canadian Institutes of Health Research; Dara Cannon: Health Research Board (HRB), Ireland (grant code HRA-POR2013-324); SC: Research Grant Council (Hong Kong)-GRF 14101714; Eveline Crone: ERC-2010-StG-263234; UD: DFG, grant FOR2107 DA1151/5-1, DA1151/5-2, SFB-TRR58, Project C09, IZKF, grant Dan3/012/17; SD: MRC-RFA-UFSP-012013 (Shared Roots MRC Flagship grant); TF: Marie Curie Programme, International Training Programme, r’Birth; DG: National Science Centre (UMO-2011/02/A/NZ5/00329); BG: National Science Centre (UMO-2011/02/A/NZ5/00329); JH: Western Sydney University Postgraduate Research Award; LH: Science Foundation Ireland, ERC; HH: Research Grant Council (Hong Kong)-GRF 14101714; LJ: Velux Stiftung, grant 369 & UZH University Research Priority Program Dynamics of Healthy Aging; AJ: DFG, grant FOR2107 JA 1890/7-1; KJ: National Science Centre (UMO-2013/09/N/HS6/02634); VK: The Russian Foundation for Basic Research (grant code 15-06-05758A); TK: DFG, grant FOR2107 KI 588/14-1, DFG, grant FOR2107 KI 588/15-1; AK: DFG, grant FOR2107 KO 4291/4-1, DFG, grant FOR2107 KO 4291/3-1; IL: The Russian Foundation for Basic Research (grant code 15-06-05758A); EL: Health and Medical Research Fund - 11121271; SiL: NHMRC-ARC Dementia Fellowship 1110414, NHMRC Dementia Research Team Grant 1095127, NHMRC Project Grant 1062319; CL-J: 537-2011, 2014849; AM: Wellcome Trust Strategic Award (104036/Z/14/Z), MRC Grant MC_PC_17209; CM: Heisenberg-Grant, German Research Foundation, DFG MO 2363/3-2; PM: Foundation for Science and Technology, Portugal - PDE/BDE/113601/2015; KN: National Science Centre (UMO-2011/02/A/NZ5/00329); PN: National Science Centre (UMO-2013/09/N/HS6/02634); JiP: NWO-Veni 451-10-007; PaR: PER and US would like to thank the Schizophrenia Research Institute and the Chief-Investigators of the Australian Schizophrenia Research Bank V. Carr, U. Schall, R. Scott, A. Jablensky, B. Mowry, P. Michie, S. Catts, F. Henskens, and C. Pantelis; AS: National Science Centre (UMO-2011/02/A/NZ5/00329); SS: European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 707730; CS-M: Carlos III Health Institute (PI13/01958), Carlos III Health Institute (PI16/00889), Carlos III Health Institute (CPII16/00048); ES: National Science Centre (UMO-2011/02/A/NZ5/00329); AT: The Russian Foundation for Basic Research (grant code 1506-05758A); DT-G: PI14/00918, PI14/00639; Leonardo Tozzi: Marie Curie Programme, International Training Programme, r’Birth; SV: IMPRS Neurocom stipend; TvE: National Center for Research Resources at the National Institutes of Health (grant numbers: NIH 1 U24 RR021992 (Function Biomedical Informatics Research Network), NIH 1 U24 RR025736-01 (Biomedical Informatics Research Network Coordinating Center; http://www.birncommunity.org) and the NIH Big Data to Knowledge (BD2K) award (U54 EB020403 to Paul Thompson). NvH: NWO-VIDI (452-11-014); MW: National Science Centre (UMO-2011/02/A/NZ5/00329); Veronica O’Keane: Meath Foundation; AV and AW: CRC Obesity Mechanism (SFB 1052) Project A1 funded by DFG. The funding sources had no role in the study design, data collection, analysis, and interpretation of the data.

BackgroundLeft-right asymmetry is an important organizing feature of the healthy brain. Various studies have reported altered structural brain asymmetry in autism spectrum disorder (ASD). However, findings have been inconsistent, likely due to limited sample sizes and low statistical power.MethodsWe investigated 1,774 subjects with ASD and 1,809 controls, from 54 datasets, for differences in the asymmetry of thickness and surface area of 34 cerebral cortical regions. We also examined global hemispheric measures of cortical thickness and area asymmetry, and volumetric asymmetries of subcortical structures. Data were obtained via the ASD Working Group of the ENIGMA (Enhancing NeuroImaging Genetics through Meta-Analysis) consortium. T1-weighted MRI data were processed with a single protocol using FreeSurfer and the Desikan-Killiany atlas.ResultsASD was significantly associated with reduced leftward asymmetry of total hemispheric average cortical thickness, compared to controls. Eight regional thickness asymmetries, distributed over the cortex, also showed significant associations with diagnosis after correction for multiple comparisons, for which asymmetry was again generally lower in ASD versus controls. In addition, the medial orbitofrontal surface area was less rightward asymmetric in ASD than controls, and the putamen volume was more leftward asymmetric in ASD than controls. The largest effect size had Cohen’sd= 0.15. Most effects did not depend on age, sex, IQ, or disorder severity.ConclusionAltered lateralized neurodevelopment is suggested in ASD, affecting widespread cortical regions with diverse functions. Large-scale analysis was necessary to reliably detect, and accurately describe, subtle alterations of structural brain asymmetry in this disorder.

We organized 10Kin1day, a pop-up scientific event with the goal to bring together neuroimaging groups from around the world to jointly analyze 10,000+ existing MRI connectivity datasets during a 3-day workshop. In this report, we describe the motivation and principles of 10Kin1day, together with a public release of 8,000+ MRI connectome maps of the human brain.

Voxel-based morphometry (VBM) is a useful approach for investigating neurostructural brain changes in dementia. We systematically reviewed VBM studies of Alzheimer's disease (AD) and mild cognitive impairment (MCI), specifically focusing on grey matter (GM) atrophy in the frontal lobe. Methods: Two searches were performed on the Pubmed database. A set of exclusion criteria was applied to ensure the selection of only VBM studies that directly investigated GM volume abnormalities in AD and/or MCI patients compared to cognitively normal controls. Results: From a total of 46 selected articles, 35 VBM studies reported GM volume reductions in the frontal lobe. The frontal subregions, where most of the volume reductions were reported, included the inferior, superior and middle frontal gyri, as well as the anterior cingulate gyrus. We also found studies in which reduced frontal GM was detected in MCI patients who converted to AD. In a minority of studies, correlations between frontal GM volumes and behavioural changes or cognitive deficits in AD patients were investigated, with variable findings. Conclusion: Results of VBM studies indicate that the frontal lobe should be regarded as an important brain area when investigating GM volume deficits in association with AD. Frontal GM loss might not be a feature specific to late AD only. Future VBM studies involving large AD samples are warranted to further investigate correlations between frontal volume deficits and both cognitive impairment and neuropsychiatric symptoms. RESUMO Morfometria baseada em voxel (MBV) é uma abordagem útil para investigar mudanças neuroestruturais no cérebro em demência. Revisamos sistematicamente estudos de MBV de doença de Alzheimer (DA) e comprometimento cognitivo leve (CCL), focando especificamente na atrofia de matéria cinzenta (MC) no lobo frontal. Métodos: Duas pesquisas foram realizadas na base de dados do Pubmed. Critérios de exclusão foram utilizados para assegurar a seleção somente de estudos de MBV que investigassem diretamente anormalidades de volume de MC em pacientes com DA e/ou CCL comparados com controles de cognição normal. Resultados: De um total de 46 artigos selecionados, 35 estudos de MBV reportaram reduções de volume de MC no lobo frontal. As sub-regiões frontais em que a maioria das reduções de volume foram encontradas incluem os giros frontais inferior, superior e médio, bem como o giro do cíngulo anterior. Também acharam-se perdas de MC em pacientes com CCL que desenvolveram DA. Uma menor parte dos estudos investigou correlações entre volumes de MC frontal e mudanças comportamentais ou déficits cognitivos em DA, com achados variáveis. Conclusão: Os resultados de estudos de MBV indicam que o lobo frontal deve ser visto como uma importante área cerebral quando da investigação de déficits de volume de MC em associação com DA. Perda de MC frontal pode não ser uma característica apenas de DA tardia. Estudos de MBV futuros com grandes amostras de pacientes com DA são necessários para investigar mais a fundo a relação entre déficits de volume frontal e sintomas de comprometimento cognitivo e neuropsiquiátricos.

The Barratt Impulsiveness Scale (BIS-11) is the most widely used questionnaire to study impulsivity in persons with psychiatric disorders, but it has rarely been applied to persons with epilepsy. The present study aimed to evaluate the usefulness of BIS-11 as a tool to explore impulsivity in two distinct epilepsy syndromes.The BIS-11 was applied to 20 patients with juvenile myoclonic epilepsy (JME) (32.5±8.95years old), 20 patients with temporal lobe epilepsy (TLE) (37.7±13.25years old), and 26 healthy controls (31.86±11.25years old). The scores in motor, attentional, and lack of planning impulsivity were compared between groups.Patients with JME showed higher scores than patients with TLE and controls in all domains: motor (JME vs TLE: 28.60 vs 13.25 (mean score), p0.001 and JME vs controls: 28.60 vs 14.12, p0.001), attentional (JME vs TLE: 21.55 vs 13.45, p0.001 and JME vs controls: 21.55 vs 14.88, p0.001) and nonplanning (JME vs TLE: 28.05 vs 13.10, p0.001 and JME vs controls: 28.05 vs 16.15, p0.001).Higher BIS-11 scores in all domains of impulsivity [i.e., motor, attentional, and lack of planning] corroborated previous findings described in patients with JME. On the other hand, BIS-11 could not demonstrate problem solving and inhibitory control deficits related to impulsive behavior, which were described in patients with TLE. Other behavioral measures may be more sensitive to some aspects of impulsivity in TLE. Our results reinforce the concept that distinct epileptic syndromes require different neuropsychological approaches, especially considering a complex construct such as impulsivity.

Background: Stigma is a major problem in schizophrenia, and the most effective way to reduce it is to provide information. But literature lacks studies evaluating long-term efficacy of mass communication. Aims: This is a pilot study to assess if a brief intervention (TV report) may have long-term effects. Method: Assessing stigma scores from subjects before and after seeing a vignette. Results: We found that the social distance and restriction to patients not only fell after a brief intervention but also kept lower after 1 and 3 months. Conclusion: We conclude that even brief intervention may create persistent impact in reducing discrimination.

Bellvitge Univ Hosp, Bellvitge Biomed Res Inst IDIBELL, Dept Psychiat, Lhospitalet De Llobregat, Barcelona, Spain

The relationship between depression and epilepsy has been known since ancient times, however, to date, it is not fully understood. The prevalence of psychiatric disorders in persons with epilepsy is high compared to general population. It is assumed that the rate of depression ranges from 20 to 55% in patients with refractory epilepsy, especially considering those with temporal lobe epilepsy caused by mesial temporal sclerosis. Temporal lobe epilepsy is a good biological model to understand the common structural basis between depression and epilepsy. Interestingly, mesial temporal lobe epilepsy and depression share a similar neurocircuitry involving: temporal lobes with hippocampus, amygdala and entorhinal and neocortical cortex; the frontal lobes with cingulate gyrus; subcortical structures, such as basal ganglia and thalamus; and the connecting pathways. We provide clinical and brain structural evidences that depression and epilepsy represent an epiphenomenon sharing similar neural networks. A relação entre depressão e epilepsia é conhecida desde a antiguidade; entretanto, até o momento, não é completamente compreendida. A prevalência de transtornos psiquiátricos nas pessoas com epilepsia é elevada quando comparada à população em geral. A taxa de depressão varia de 20 a 55% nos pacientes com epilepsia refratária, especialmente considerando-se aqueles com epilepsia do lobo temporal causada por esclerose mesial temporal. A epilepsia do lobo temporal é um bom modelo biológico para compreender as bases estruturais comuns entre a epilepsia e a depressão. É relevante ressaltar que a epilepsia do lobo mesial e a depressão apresentam circuitos similares envolvendo: os lobos temporais com o hipocampo, a amigdala, o córtex entorrinal e o neocortex; os lobos frontais com o giro cíngulo; estruturas subcorticais, como os núcleos da base e o tálamo, e suas vias de conexão. Postulamos por meio de evidências clínicas e estruturais que a depressão e a epilepsia representam um epifenômeno com redes neuronais similares.

STUDY OBJECTIVES To investigate muscle sympathetic nerve activity (MSNA) response and executive performance during mental stress in obstructive sleep apnea (OSA). METHODS Individuals with no other comorbidities (age = 52 ± 1 y, body mass index = 29 ± 0.4, kg/m2) were divided into two groups: (1) control (n = 15) and (2) untreated OSA (n = 20) defined by polysomnography. Mini-Mental State of Examination (MMSE) and Inteligence quocient (IQ) were assessed. Heart rate (HR), blood pressure (BP), and MSNA (microneurography) were measured at baseline and during 3 min of the Stroop Color Word Test (SCWT). Sustained attention and inhibitory control were assessed by the number of correct answers and errors during SCWT. RESULTS Control and OSA groups (apnea-hypopnea index, AHI = 8 ± 1 and 47 ± 1 events/h, respectively) were similar in age, MMSE, and IQ. Baseline HR and BP were similar and increased similarly during SCWT in control and OSA groups. In contrast, baseline MSNA was higher in OSA compared to controls. Moreover, MSNA significantly increased in the third minute of SCWT in OSA, but remained unchanged in controls (P < 0.05). The number of correct answers was lower and the number of errors was significantly higher during the second and third minutes of SCWT in the OSA group (P < 0.05). There was a significant correlation (P < 0.01) between the number of errors in the third minute of SCWT with AHI (r = 0.59), arousal index (r = 0.55), and minimum O2 saturation (r = -0.57). CONCLUSIONS As compared to controls, MSNA is increased in patients with OSA at rest, and further significant MSNA increments and worse executive performance are seen during mental stress. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov, registration number: NCT002289625.

The presence of cognitive impairment is a frequent complaint among elderly individuals in the general population. This study aimed to investigate the relationship between aging-related regional gray matter (rGM) volume changes and cognitive performance in healthy elderly adults. Morphometric magnetic resonance imaging (MRI) measures were acquired in a community-based sample of 170 cognitively-preserved subjects (66 to 75 years). This sample was drawn from the "Sao Paulo Ageing and Health" study, an epidemiological study aimed at investigating the prevalence and risk factors for Alzheimer's disease in a low income region of the city of Sao Paulo. All subjects underwent cognitive testing using a cross-culturally battery validated by the Research Group on Dementia 10/66 as well as the SKT (applied on the day of MRI scanning). Blood genotyping was performed to determine the frequency of the three apolipoprotein E allele variants (APOE e2/e3/e4) in the sample. Voxelwise linear correlation analyses between rGM volumes and cognitive test scores were performed using voxel-based morphometry, including chronological age as covariate. There were significant direct correlations between worse overall cognitive performance and rGM reductions in the right orbitofrontal cortex and parahippocampal gyrus, and also between verbal fluency scores and bilateral parahippocampal gyral volume (p < 0.05, familywise-error corrected for multiple comparisons using small volume correction). When analyses were repeated adding the presence of the APOE e4 allele as confounding covariate or excluding a minority of APOE e2 carriers, all findings retained significance. These results indicate that rGM volumes are relevant biomarkers of cognitive deficits in healthy aging individuals, most notably involving temporolimbic regions and the orbitofrontal cortex.

OBJECTIVE: To make individual assessments using automated quantification methodology in order to screen for perfusion abnormalities in cerebral SPECT examinations among a sample of subjects with OCD. METHODS: Statistical parametric mapping (SPM) was used to compare 26 brain SPECT images from patients with OCD individually with an image bank of 32 normal subjects, using the statistical threshold of p < 0.05 (corrected for multiple comparisons at the level of individual voxels or clusters). The maps were analyzed, and regions presenting voxels that remained above this threshold were sought. RESULTS: Six patients from a sample of 26 OCD images showed abnormalities at cluster or voxel level, considering the criteria described above, which represented 23.07%. However, seven images from the normal group of 32 were also indicated as cases of perfusional abnormality, representing 21.8% of the sample. CONCLUSION: The automated quantification method was not considered to be a useful tool for clinical practice, for analyses complementary to visual inspection. OBJETIVO: Avaliar uma amostra de pacientes com transtorno obsessivo-compulsivo (TOC), individualmente, empregando uma metodologia de quantificação automatizada para rastrear anormalidades de perfusão em exames de SPECT cerebral. MÉTODOS: Foi utilizado o Statistical Parametric Mapping (SPM) para comparar 26 imagens de SPECT cerebral de pacientes com TOC, individualmente, com um banco de 32 imagens de voluntários normais, usando o limiar estatístico de p < 0,05 (corrigido para comparações múltiplas ao nível do voxel individual ou clusters). Os mapas foram analisados procurando por regiões que apresentassem voxels acima desse limiar. RESULTADOS: Seis pacientes da amostra de 26 imagens com TOC mostraram anormalidades ao nível do cluster ou voxel, considerando os critérios descritos acima, os quais representaram 23,07%. Contudo, sete imagens do grupo de 32 voluntários normais também foram apontadas com anormalidades de perfusão, que representou 21,8% da amostra. CONCLUSÃO: O método de quantificação automatizada não foi considerado como uma ferramenta útil na prática clínica, como forma de análise complementar à inspeção visual.

BACKGROUND: Schizophrenia is one of the most intriguing and studied psychiatric diseases and its physiopathology has advanced a lot in the last century. OBJECTIVE: To review the most important advances in the physiopathology of schizophrenia. METHOD: Review of the literature of each proposed topic by articles searched in Medline and/or chosen accordingly the authors’ experience. RESULTS: The dopaminergic hypothesis was one of the first ethiological theories and until today is among the ones that presents the most consistent evidences. However, it fails to explain important features found in schizophrenia, such as the natural history, the cognitive impairments and the structural abnormalities. Evidences provided by epidemiological studies of genetic and environmental risk factors, associated with the findings of neuropathological and neuroimaging studies, suggest an interactive model with several factors acting together to create a global alteration of the brain development. CONCLUSION: The physiophatology of schizophrenia has advanced a lot in the last century, evolving from unicausal theories towards more complex models that consider the interaction among several genetic and environmental factors.

CONTEXTO: A esquizofrenia é uma das mais intrigantes doenças psiquiátricas e, talvez por isso, a mais pesquisada, com grandes avanços sobre sua fisiopatologia no último século. OBJETIVO: Revisar os principais avanços na compreensão fisiopatológica da esquizofrenia. MÉTODO: Revisão da literatura para cada tópico proposto a partir de artigos levantados no Medline e/ou considerados importantes a partir da experiência dos autores. RESULTADOS: A hipótese dopaminérgica representa uma das primeiras teorias etiológicas e permanece até os dias atuais como uma das que apresenta evidências mais consistentes. No entanto, essa teoria falha em explicar a história natural, os prejuízos cognitivos e as alterações estruturais encontradas na esquizofrenia. A demonstração de estudos epidemiológicos de fatores de risco genéticos e ambientais, somados aos estudos neuropatológicos e de neuroimagem, sugerem um modelo interativo em que inúmeros fatores atuam conjuntamente para alterações mais globais do desenvolvimento cerebral. CONCLUSÃO: A compreensão fisiopatológica da esquizofrenia avançou bastante no último século, evoluindo de teorias etiológicas unicausais para modelos mais complexos que consideram a interação de inúmeros fatores genéticos e ambientais.BACKGROUND: Schizophrenia is one of the most intriguing and studied psychiatric diseases and its physiopathology has advanced a lot in the last century. OBJECTIVE: To review the most important advances in the physiopathology of schizophrenia. METHOD: Review of the literature of each proposed topic by articles searched in Medline and/or chosen accordingly the authors’ experience. RESULTS: The dopaminergic hypothesis was one of the first ethiological theories and until today is among the ones that presents the most consistent evidences. However, it fails to explain important features found in schizophrenia, such as the natural history, the cognitive impairments and the structural abnormalities. Evidences provided by epidemiological studies of genetic and environmental risk factors, associated with the findings of neuropathological and neuroimaging studies, suggest an interactive model with several factors acting together to create a global alteration of the brain development. CONCLUSION: The physiophatology of schizophrenia has advanced a lot in the last century, evolving from unicausal theories towards more complex models that consider the interaction among several genetic and environmental factors.

Diversos estudos têm demonstrado associação entre fatores de risco cardiovascular e desenvolvimento de declínio cognitivo. Também há evidências do aumento das taxas de morbimortalidade em pacientes com doenças cardiovasculares e déficit cognitivo. Dentre os fatores de risco cardiovascular, hipertensão arterial e insuficiência cardíaca apresentaram forte associação com a presença de déficit cognitivo, entretanto os mecanismos cerebrais subjacentes não foram totalmente esclarecidos. Nos pacientes cardiopatas, o prejuízo cognitivo se dá principalmente nos aspectos de memória (fixação e aprendizado) e processamento das informações. Nesse artigo, revisa-se os achados de neuroimagem observados em amostras de pacientes com fatores de risco cardiovascular com declínio cognitivo, incluindo achados regionais de anormalidades volumétricas, hiperintensidade de substância branca, acidentes vasculares silenciosos, infartos lacunares e déficits funcionais na perfusão cerebral global (associada à redução do débito cardíaco) e perfusão cerebral regional. Discute-se, também, as implicações destes achados para a fisiopatologia do declínio cognitivo e suas aplicações clínicas. Finalmente, aborda-se o potencial de utilização de novas técnicas de imagem em estudos futuros na avaliação das alterações estruturais e funcionais associadas a fatores de riscos vasculares em amostras de base populacional.Several research studies have shown associations between cardiovascular risk factors and the development of cognitive decline. There is also evidence of an increased rate of morbidity and mortality in subjects with cardiovascular diseases with concomitant cognitive decline. Congestive heart failure and hypertension, among all cardiovascular risk factors, have shown a strong relationship with the presence of cognitive deficits, but the brain mechanisms underlying such association have not yet been clarified. The cognitive decline associated with cardiac diseases is characterized mainly by impairments of memory (learning and fixation), attention and information processing. In this article, we review neuroimaging abnormalities that may be found in samples of subjects presenting with cardiovascular risk factors and cognitive decline, including regional brain volumetric changes, white matter hyperintensities, silent brain infarcts, lacunars infarcts, and functional deficits in global blood flow (associated to reduced cardiac output) or regional cerebral blood flow. We discuss the implications of these findings to the knowledge about the pathophysiology of cognitive deficits associated with cardiovascular risk factors, as well as their potential clinical applications. Finally, we discuss the potential use of novel imaging technologies in future studies evaluating abnormalities in brain structure and function related to cardiovascular risk factors, in large samples of elderly patients.

A maconha é a droga ilícita mais utilizada. Apesar disto, apenas um pequeno número de estudos investigaram as conseqüências neurotóxicas de longo prazo do uso de cannabis. As técnicas de neuroimagem se constituem em poderosos instrumentos para investigar alterações neuroanatômicas e neurofuncionais e suas correlações clínicas e neuropsicológicas. Uma revisão computadorizada da literatura foi conduzida nos indexadores MEDLINE e PsycLIT entre 1966 e novembro de 2004 com os termos 'cannabis', 'marijuana', 'neuroimaging', 'magnetic resonance', 'computed tomography', 'positron emission tomography', 'single photon emission computed tomography", 'SPET', 'MRI' e 'CT'. Estudos de neuroimagem estrutural apresentam resultados conflitantes, com a maioria dos estudos não relatando atrofia cerebral ou alterações volumétricas regionais. Contudo, há uma pequena evidência de que usuários de longo prazo que iniciaram um uso regular no início da adolescência apresentam atrofia cerebral assim como redução na substância cinzenta. Estudos de neuroimagem funcional relatam aumento na atividade neural em regiões que podem estar relacionadas com intoxicação por cannabis e alteração do humor (lobos frontais mesial e orbital) e redução na atividade de regiões relacionadas com funções cognitivas prejudicadas durante a intoxicação aguda. A questão crucial se efeitos neurotóxicos residuais ocorrem após o uso prolongado e regular de maconha permanece obscura, não existindo até então estudo endereçando esta questão diretamente. Estudos de neuroimagem com melhores desenhos, combinados com avaliação cognitiva, podem ser elucidativos neste aspecto.Cannabis is the most widely used illicit drug. Despite this, only a small number of studies have investigated the long-term neurotoxic consequences of cannabis use. Structural and functional neuroimaging techniques are powerful research tools to investigate possible cannabis-induced pathophysiological changes. A computer literature review was conducted in the MEDLINE and PsycLIT databases between 1966 and November of 2004 with the search terms 'cannabis', 'marijuana', 'neuroimaging', 'magnetic resonance', 'computed tomography', 'positron emission tomography', 'single photon emission computed tomography", 'SPET', 'MRI' and 'CT'. Structural neuroimaging studies have yielded conflicting results. Most studies report no evidence of cerebral atrophy or regional changes in tissue volumes, and one study suggested that long-term users who started regular use on early adolescence have cerebral atrophy as well as reduction in gray matter. However, several methodological shortcomings limit the interpretation of these results.Functional neuroimaging studies have reported increases in neural activity in regions that may be related with cannabis intoxication or mood-change effects (orbital and mesial frontal lobes, insula, and anterior cingulate) and decreases in activity of regions related with cognitive functions impaired during acute intoxication.The important question whether residual neurotoxic effects occur after prolonged and regular use of cannabis remains unclear, with no study addressing this question directly. Better designed neuroimaging studies, combined with cognitive evaluation, may be elucidative on this issue.

A maconha é a droga ilícita mais utilizada. Apesar disto, apenas um pequeno número de estudos investigaram as conseqüências neurotóxicas de longo prazo do uso de cannabis. As técnicas de neuroimagem se constituem em poderosos instrumentos para investigar alterações neuroanatômicas e neurofuncionais e suas correlações clínicas e neuropsicológicas. Uma revisão computadorizada da literatura foi conduzida nos indexadores MEDLINE e PsycLIT entre 1966 e novembro de 2004 com os termos 'cannabis', 'marijuana', 'neuroimaging', 'magnetic resonance', 'computed tomography', 'positron emission tomography', 'single photon emission computed tomography", 'SPET', 'MRI' e 'CT'. Estudos de neuroimagem estrutural apresentam resultados conflitantes, com a maioria dos estudos não relatando atrofia cerebral ou alterações volumétricas regionais. Contudo, há uma pequena evidência de que usuários de longo prazo que iniciaram um uso regular no início da adolescência apresentam atrofia cerebral assim como redução na substância cinzenta. Estudos de neuroimagem funcional relatam aumento na atividade neural em regiões que podem estar relacionadas com intoxicação por cannabis e alteração do humor (lobos frontais mesial e orbital) e redução na atividade de regiões relacionadas com funções cognitivas prejudicadas durante a intoxicação aguda. A questão crucial se efeitos neurotóxicos residuais ocorrem após o uso prolongado e regular de maconha permanece obscura, não existindo até então estudo endereçando esta questão diretamente. Estudos de neuroimagem com melhores desenhos, combinados com avaliação cognitiva, podem ser elucidativos neste aspecto. Cannabis is the most widely used illicit drug. Despite this, only a small number of studies have investigated the long-term neurotoxic consequences of cannabis use. Structural and functional neuroimaging techniques are powerful research tools to investigate possible cannabis-induced pathophysiological changes. A computer literature review was conducted in the MEDLINE and PsycLIT databases between 1966 and November of 2004 with the search terms 'cannabis', 'marijuana', 'neuroimaging', 'magnetic resonance', 'computed tomography', 'positron emission tomography', 'single photon emission computed tomography", 'SPET', 'MRI' and 'CT'. Structural neuroimaging studies have yielded conflicting results. Most studies report no evidence of cerebral atrophy or regional changes in tissue volumes, and one study suggested that long-term users who started regular use on early adolescence have cerebral atrophy as well as reduction in gray matter. However, several methodological shortcomings limit the interpretation of these results.Functional neuroimaging studies have reported increases in neural activity in regions that may be related with cannabis intoxication or mood-change effects (orbital and mesial frontal lobes, insula, and anterior cingulate) and decreases in activity of regions related with cognitive functions impaired during acute intoxication.The important question whether residual neurotoxic effects occur after prolonged and regular use of cannabis remains unclear, with no study addressing this question directly. Better designed neuroimaging studies, combined with cognitive evaluation, may be elucidative on this issue.