EDSON AMARO JUNIOR
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Radiologia, Faculdade de Medicina - Docente
LIM/44 - Laboratório de Ressonância Magnética em Neurorradiologia, Hospital das Clínicas, Faculdade de Medicina
LIM/44 - Laboratório de Ressonância Magnética em Neurorradiologia, Hospital das Clínicas, Faculdade de Medicina
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- Stroke lesion in cortical neural circuits and post-stroke incidence of major depressive episode: A 4-month prospective study(2011) TERRONI, Luisa; AMARO JR., Edson; IOSIFESCU, Dan V.; TINONE, Gisela; SATO, Joao Ricardo; LEITE, Claudia Costa; SOBREIRO, Matildes F. M.; LUCIA, Mara Cristina Souza; SCAFF, Milberto; FRAGUAS, RenerioObjective. Little is known about the relevance of lesion in neural circuits reported to be associated with major depressive disorder. We investigated the association between lesion stroke size in the limbic-cortical-striatal-pallidal-thalamic (LCSPT) circuit and incidence of major depressive episode (MDE). Methods. We enrolled 68 patients with first-ever ischemic stroke and no history of major depressive disorder. Neurological and psychiatric examinations were performed at three time-points. We diagnosed major depressive episode, following DSM-IV criteria. Lesion location and volume were determined with magnetic resonance imaging, using a semi-automated method based on the Brodmann Cytoarchitectonic Atlas. Results. Twenty-one patients (31%) experienced major depressive episode. Larger lesions in the left cortical regions of the LCSPT circuit (3,760 vs. 660 mm(3); P = 0.004) were associated with higher incidence of MDE. Secondary analyses revealed that major depressive episode was associated with larger lesions in areas of the medial prefrontal cortex including the ventral (BA24) and dorsal anterior cingulate cortex (BA32) and subgenual cortex (BA25); and also the subiculum (BA28/36) and amygdala (BA34). Conclusions Our findings indicate that depression due to stroke is aetiologically related to the disruption of the left LCSPT circuit and support the relevance of the medial prefrontal cortex dysfunction in the pathophysiology of depression.
- Age-effects in white matter using associated diffusion tensor imaging and magnetization transfer ratio during late childhood and early adolescence(2016) MOURA, Luciana Monteiro; KEMPTON, Matthew; BARKER, Gareth; SALUM, Giovanni; GADELHA, Ary; PAN, Pedro Mario; HOEXTER, Marcelo; AQUILLA, Marco Antonio Gomes Del; PICON, Felipe Almeida; ANES, Mauricio; OTADUY, Maria Concepcion Garcia; AMARO JR., Edson; ROHDE, Luis Augusto; MCGUIRE, Philip; BRESSAN, Rodrigo Affonseca; SATO, Joao Ricardo; JACKOWSKI, Andrea ParolinIn the last decade, several studies have described the typical brain white matter maturation in children and adolescents. Diffusion tensor imaging (DTI) is the most frequent MRI technique used to investigate the structural changes across development. However, few previous studies have used the magnetization transfer ratio (MTR), which gives a closer measure of myelin content. Here, we employed both techniques for the same sample of 176 typically developing children from 7 to 14 years of age. We investigated the associations between DTI parameters and MTR measure, to assess the myelination in the brain in development. Secondly, we investigated age-effects on DTI parameters (fractional anisotropy, axial, radial and mean diffusivities) and MTR. No significant correlations between MTR and DTI parameters were observed. In addition, a significant age-effect was detected for DTI data but was not visible for MTR data. Thereby, changes in white matter at this age might be primarily correlated with microstructural changes.
- Long-term stability of the cortical volumetric profile and the functional human connectome throughout childhood and adolescence(2021) SATO, Joao Ricardo; BIAZOLI, Claudinei Eduardo; ZUGMAN, Andre; PAN, Pedro Mario; BUENO, Ana Paula Arantes; MOURA, Luciana Monteiro; GADELHA, Ary; PICON, Felipe Almeida; JR, Edson Amaro; SALUM, Giovanni Abrahao; MIGUEL, Euripedes Constantino; ROHDE, Luis Augusto; BRESSAN, Rodrigo Affonseca; JACKOWSKI, Andrea ParolinThere is compelling evidence showing that between-subject variability in several functional and structural brain features is sufficient for unique identification in adults. However, individuation of brain functional connectomes depends on the stabilization of neurodevelopmental processes during childhood and adolescence. Here, we aimed to (1) evaluate the intra-subject functional connectome stability over time for the whole brain and for large scale functional networks and (2) determine the long-term identification accuracy or 'fingerprinting' for the cortical volumetric profile and the functional connectome. For these purposes, we analysed a longitudinal cohort of 239 children and adolescents scanned in two sessions with an interval of approximately 3 years (age range 6-15 years at baseline and 9-18 years at follow-up). Corroborating previous results using short between-scan intervals in children and adolescents, we observed a moderate identification accuracy (38%) for the whole functional profile. In contrast, identification accuracy using cortical volumetric profile was 95%. Among the large-scale networks, the default-mode (26.8%), the frontoparietal (23.4%) and the dorsal-attention (27.6%) networks were the most discriminative. Our results provide further evidence for a protracted development of specific individual structural and functional connectivity profiles.
- Associations between children's family environment, spontaneous brain oscillations, and emotional and behavioral problems(2019) SATO, Joao Ricardo; JR, Claudinei Eduardo Biazoli; SALUM, Giovanni Abrahao; GADELHA, Ary; CROSSLEY, Nicolas; VIEIRA, Gilson; ZUGMAN, Andre; PICON, Felipe Almeida; PAN, Pedro Mario; HOEXTER, Marcelo Queiroz; JR, Edson Amaro; ANES, Mauricio; MOURA, Luciana Monteiro; DEL'AQUILLA, Marco Antonio Gomes; MCGUIRE, Philip; ROHDEZ, Luis Augusto; MIGUEL, Euripedes Constantino; BRESSAN, Rodrigo Affonseca; JACKOWSKI, Andrea ParolinThe family environment in childhood has a strong effect on mental health outcomes throughout life. This effect is thought to depend at least in part on modifications of neurodevelopment trajectories. In this exploratory study, we sought to investigate whether a feasible resting-state fMRI metric of local spontaneous oscillatory neural activity, the fractional amplitude of low-frequency fluctuations (fALFF), is associated with the levels of children's family coherence and conflict. Moreover, we sought to further explore whether spontaneous activity in the brain areas influenced by family environment would also be associated with a mental health outcome, namely the incidence of behavioral and emotional problems. Resting-state fMRI data from 655 children and adolescents (6-15years old) were examined. The quality of the family environment was found to be positively correlated with fALFF in the left temporal pole and negatively correlated with fALFF in the right orbitofrontal cortex. Remarkably, increased fALFF in the temporal pole was associated with a lower incidence of behavioral and emotional problems, whereas increased fALFF in the orbitofrontal cortex was correlated with a higher incidence.
- Effects of the brain-derived neurotropic factor variant Val66Met on cortical structure in late childhood and early adolescence(2018) ARAUJO, Celia Maria de; ZUGMAN, Andre; SWARDFAGER, Walter; BELANGERO, Sintia Iole Nogueira; OTA, Vanessa Kiyomi; SPINDOLA, Leticia Maria; HAKONARSON, Hakon; PELLEGRINO, Renata; GADELHA, Ary; SALUM, Giovanni Abrahao; PAN, Pedro Mario; MOURA, Luciana Monteiro de; AQUILLA, Marco Del; PICON, Felipe Almeida; AMARO JR., Edson; SATO, Joao Ricardo; BRIETZKE, Elisa; GRASSI-OLIVEIRA, Rodrigo; ROHDE, Luis Augusto P.; MIGUEL, Euripedes Constantino; BRESSAN, Rodrigo A.; JACKOWSKI, Andrea ParolinBackground: The brain-derived neurotrophic factor (BDNF) Val66Met polymorphism (rs6265) has been associated with several neuropsychiatric disorders and regional structural brain changes in adults, but little is known about Val66Met's effect on brain morphology during typical or atypical neurodevelopment. Windows of vulnerability to psychopathology may be associated with the different alleles of the Val66Met polymorphism during childhood and adolescence. Methodology: We investigated the effect of Val66Met on cortical thickness in MRI scans of 718 children and adolescents (6-12 years old) with typical development, and in those meeting DSM criteria for a psychiatric disorder. Results: Val66Met had a significant effect on cortical thickness. Considering the typically developing group, Met carriers presented thicker parietal and occipital lobes and prefrontal cortices compared to Val homozygotes. Met carriers with psychiatric disorders presented thicker medial and lateral temporal cortices than Val homozygotes. Furthermore, a significant genotype x psychiatric diagnosis interaction was found: Met-carriers with a psychiatric diagnosis presented thinner bilateral prefrontal cortices than Val homozygotes. Conclusion: This study provides evidence that Val66Met is associated with cortical maturation in children and adolescents with and without psychiatric disorders.
- Temporal Stability of Network Centrality in Control and Default Mode Networks: Specific Associations with Externalizing Psychopathology in Children and Adolescents(2015) SATO, Joao Ricardo; BIAZOLI JR., Claudinei Eduardo; SALUM, Giovanni Abrahao; GADELHA, Ary; CROSSLEY, Nicolas; SATTERTHWAITE, Theodore D.; VIEIRA, Gilson; ZUGMAN, Andre; PICON, Felipe Almeida; PAN, Pedro Mario; HOEXTER, Marcelo Queiroz; ANES, Mauricio; MOURA, Luciana Monteiro; DEL'AQUILLA, Marco Antonio Gomes; AMARO JR., Edson; MCGUIRE, Philip; LACERDA, Acioly L. T.; ROHDE, Luis Augusto; MIGUEL, Euripedes Constantino; JACKOWSKI, Andrea Parolin; BRESSAN, Rodrigo AffonsecaAbnormal connectivity patterns have frequently been reported as involved in pathological mental states. However, most studies focus on ""static,"" stationary patterns of connectivity, which may miss crucial biological information. Recent methodological advances have allowed the investigation of dynamic functional connectivity patterns that describe non-stationary properties of brain networks. Here, we introduce a novel graphical measure of dynamic connectivity, called time-varying eigenvector centrality (tv-EVC). In a sample 655 children and adolescents (7-15 years old) from the Brazilian ""High Risk Cohort Study for Psychiatric Disorders"" who were imaged using resting-state fMRI, we used this measure to investigate age effects in the temporal in control and default-mode networks (CN/DMN). Using support vector regression, we propose a network maturation index based on the temporal stability of tv-EVC. Moreover, we investigated whether the network maturation is associated with the overall presence of behavioral and emotional problems with the Child Behavior Checklist. As hypothesized, we found that the tv-EVC at each node of CN/DMN become more stable with increasing age (P < 0.001 for all nodes). In addition, the maturity index for this particular network is indeed associated with general psychopathology in children assessed by the total score of Child Behavior Checklist (P = 0.027). Moreover, immaturity of the network was mainly correlated with externalizing behavior dimensions. Taken together, these results suggest that changes in functional network dynamics during neurodevelopment may provide unique insights regarding pathophysiology. (C) 2015 Wiley Periodicals, Inc.
- Motor Readiness Increases Brain Connectivity Between Default-Mode Network and Motor Cortex: Impact on Sampling Resting Periods from fMRI Event-Related Studies(2015) BAZAN, Paulo Rodrigo; BIAZOLI JR., Claudinei Eduardo; SATO, Joao Ricardo; AMARO JR., EdsonThe default-mode network (DMN) has been implicated in many conditions. One particular function relates to its role in motor preparation. However, the possibly complex relationship between DMN activity and motor preparation has not been fully explored. Dynamic interactions between default mode and motor networks may compromise the ability to evaluate intrinsic connectivity using resting period data extracted from task-based experiments. In this study, we investigated alterations in connectivity between the DMN and the motor network that are associated with motor readiness during the intervals between motor task trials. fMRI data from 20 normal subjects were acquired under three conditions: pure resting state; resting state interleaved with brief, cued right-hand movements at constant intervals (lower readiness); and resting state interleaved with the same movements at unpredictable intervals (higher readiness). The functional connectivity between regions of motor and DMNs was assessed separately for movement periods and intertask intervals. We found a negative relationship between the DMN and the left sensorimotor cortex during the task periods for both motor conditions. Furthermore, during the intertask intervals of the unpredictable condition, the DMN showed a positive relationship with right sensorimotor cortex and a negative relation with the left sensorimotor cortex. These findings indicate a specific modulation on motor processing according to the state of motor readiness. Therefore, connectivity studies using task-based fMRI to probe DMN should consider the influence of motor system modulation when interpreting the results.
- Cognitive performance in transient global hypoxic brain injury due to moderate drowning(2018) NUCCI, Mariana Penteado; LUKASOVA, Katerina; VIEIRA, Gilson; SATO, Joao Ricardo; AMARO JUNIOR, EdsonIntroduction: Drowning is a serious and frequently neglected public health threat. Primary respiratory impairment after submersion often leads to brain dysfunction. Depending on the period of global hypoxia (respiratory failure), clinical aspects of neurological dysfunction are evident on the first evaluation after the water rescue. Nowadays, many neuropsychological assessments after drowning are inconclusive, with some studies reporting only minor neurological or cognitive impairments. The aim of this study is to identify measures in neuropsychological tests that most contribute to classify volunteers as moderate drowning subjects or healthy controls. To the best of our knowledge, this study is the first neuropsychological prospective case-control study of moderate drowning in a country with large coastal cities. Method: Fifteen moderate drowning patients (DP), who met the inclusion criteria, were compared with 18 healthy controls (HC). All subjects were assessed on memory, learning, visual spatial ability, executive function, attention, and general intellectual functioning and underwent structural magnetic resonance (MR) imaging of the brain at 3.0 T, in order to exclude subjects with anatomic abnormalities. Results: Neuropsychological tests assessing learning, execution function, and verbal fluencyRey Auditory Verbal Learning Test (RAVLT) general learning ability, Digit Span total, Phonological Verbal Fluency (total FAS correct), and Brief Visuospatial Memory Test Revised (BVMT) correct recognitionhave the strongest discriminating ability, using predictive models via the partial least squares (PLS) approach for data classification, while the other tests have shown similar predictive values between groups. Conclusions: Learning, execution function, and verbal fluency domains were the most critically affected domains. Serious impairments in the same domains have already been reported in severe drowning cases, and we hypothesize that subtle alterations found in moderate drowning cases, although not sufficient to be detected in daily routine, may possibly have a negative impact on cognitive reserve.
- Genetic risk for Alzheimer's disease and functional brain connectivity in children and adolescents(2019) AXELRUD, Luiza Kvitko; SATO, Joao Ricardo; SANTORO, Marcos Leite; TALARICO, Fernanda; PINE, Daniel Samuel; ROHDE, Luis Augusto; ZUGMAN, Andre; AMARO JR., Edson; BRESSAN, Rodrigo Affonseca; GRASSI-OLIVEIRA, Rodrigo; PAN, Pedro Mario; HOFFMANN, Mauricio Scopel; SIMIONI, Andre Rafael; GUINJOAN, Salvador Martin; HAKONARSON, Hakon; BRIETZKE, Elisa; GADELHA, Ary; SILVA, Renata Pellegrino da; HOEXTER, Marcelo Queiroz; MIGUEL, Euripedes Constantino; BELANGERO, Sintia Iole; SALUM, Giovanni AbrahaoResearch suggested accumulation of tau proteins might lead to the degeneration of functional networks. Studies investigating the impact of genetic risk for Alzheimer's disease (AD) on early brain connections might shed light on mechanisms leading to AD development later in life. Here, we aim to investigate whether the polygenic risk score for Alzheimer's disease (AD-PRS) influences the connectivity among regions susceptible to tau pathology during childhood and adolescence. Participants were youth, aged 6 -14 years, and recruited in Porto Alegre (discovery sample, n = 332) and Sao Paulo (replication sample, n = 304), Brazil. Subjects underwent genotyping and 6-min resting state funcional magnetic resonance imaging. Connections between the local maxima of tau pathology networks were used as dependent variables. The AD-PRS was associated with the connectivity between the right precuneus and the right superior temporal gyrus (discovery sample: beta = 0.180, p(adjusted) = 0.036; replication sample: beta = 0.202, p = 0.031). This connectivity was also associated with inhibitory control (beta = 0.157, p(adjusted) = 0.035) and moderated the association between the AD-PRS and both immediate and delayed recall. These findings suggest the AD-PRS may affect brain connectivity in youth, which might impact memory performance and inhibitory control in early life.
- Global efficiency of the motor network is decreased in Parkinson's disease in comparison with essential tremor and healthy controls(2021) NOVAES, Natalia Pelizari; BALARDIN, Joana Bisol; HIRATA, Fabiana Campos; MELO, Luciano; JR, Edson Amaro; BARBOSA, Egberto Reis; SATO, Joao Ricardo; CARDOSO, Ellison FernandoBackground Graph theory (GT) is a mathematical field that analyses complex networks that can be applied to neuroimaging to quantify brain's functional systems in Parkinson's disease (PD) and essential tremor (ET). Objectives To evaluate the functional connectivity (FC) measured by the global efficiency (GE) of the motor network in PD and compare it to ET and healthy controls (HC), and correlate it to clinical parameters. Methods 103 subjects (54PD, 18ET, 31HC) were submitted to structural and functional MRI. A network was designed with regions of interest (ROIs) involved in motor function, and GT was applied to determine its GE. Clinical parameters were analyzed as covariates to estimate the impact of disease severity and medication on GE. Results GE of the motor circuit was reduced in PD in comparison with HC (p .042). Areas that most contributed to it were left supplementary motor area (SMA) and bilateral postcentral gyrus. Tremor scores correlated positively with GE of the motor network in PD subgroups. For ET, there was an increase in the connectivity of the anterior cerebellar network to the other ROIs of the motor circuit in comparison with PD. Conclusions FC measured by the GE of the motor network is diminished in PD in comparison with HC, especially due to decreased connectivity of left SMA and bilateral postcentral gyrus. This finding supports the theory that there is a global impairment of the motor network in PD, and it does not affect just the basal ganglia, but also areas associated with movement modulation. The ET group presented an increased connectivity of the anterior cerebellar network to the other ROIs of the motor circuit when compared to PD, which reinforces what it is known about its role in this pathology.