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1.
Cereb Cortex ; 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34791077

RESUMO

Abnormal tactile response is an integral feature of Autism Spectrum Disorders (ASDs), and hypo-responsiveness to tactile stimuli is often associated with the severity of ASDs core symptoms. Patients with Phelan-McDermid syndrome (PMS), caused by mutations in the SHANK3 gene, show ASD-like symptoms associated with aberrant tactile responses. The neural underpinnings of these abnormalities are still poorly understood. Here we investigated, in Shank3b-/- adult mice, the neural substrates of whisker-guided behaviors, a key component of rodents' interaction with the surrounding environment. We assessed whisker-dependent behaviors in Shank3b-/- adult mice and age-matched controls, using the textured novel object recognition (tNORT) and whisker nuisance (WN) test. Shank3b-/- mice showed deficits in whisker-dependent texture discrimination in tNORT and behavioral hypo-responsiveness to repetitive whisker stimulation in WN. Sensory hypo-responsiveness was accompanied by a significantly reduced activation of the primary somatosensory cortex (S1) and hippocampus, as measured by c-fos mRNA induction, a proxy of neuronal activity following whisker stimulation. Moreover, resting-state fMRI showed a significantly reduced S1-hippocampal connectivity in Shank3b mutants, in the absence of altered connectivity between S1 and other somatosensory areas. Impaired crosstalk between hippocampus and S1 might underlie Shank3b-/- hypo-reactivity to whisker-dependent cues, highlighting a potentially generalizable somatosensory dysfunction in ASD.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34651219

RESUMO

PURPOSE: FDG-PET is an established supportive biomarker in dementia with Lewy bodies (DLB), but its diagnostic accuracy is unknown at the mild cognitive impairment (MCI-LB) stage when the typical metabolic pattern may be difficultly recognized at the individual level. Semiquantitative analysis of scans could enhance accuracy especially in less skilled readers, but its added role with respect to visual assessment in MCI-LB is still unknown. METHODS: We assessed the diagnostic accuracy of visual assessment of FDG-PET by six expert readers, blind to diagnosis, in discriminating two matched groups of patients (40 with prodromal AD (MCI-AD) and 39 with MCI-LB), both confirmed by in vivo biomarkers. Readers were provided in a stepwise fashion with (i) maps obtained by the univariate single-subject voxel-based analysis (VBA) with respect to a control group of 40 age- and sex-matched healthy subjects, and (ii) individual odds ratio (OR) plots obtained by the volumetric regions of interest (VROI) semiquantitative analysis of the two main hypometabolic clusters deriving from the comparison of MCI-AD and MCI-LB groups in the two directions, respectively. RESULTS: Mean diagnostic accuracy of visual assessment was 76.8 ± 5.0% and did not significantly benefit from adding the univariate VBA map reading (77.4 ± 8.3%) whereas VROI-derived OR plot reading significantly increased both accuracy (89.7 ± 2.3%) and inter-rater reliability (ICC 0.97 [0.96-0.98]), regardless of the readers' expertise. CONCLUSION: Conventional visual reading of FDG-PET is moderately accurate in distinguishing between MCI-LB and MCI-AD, and is not significantly improved by univariate single-subject VBA but by a VROI analysis built on macro-regions, allowing for high accuracy independent of reader skills.

3.
Br J Clin Psychol ; 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34651307

RESUMO

OBJECTIVE: Huntington's disease (HD) is a dramatic neurodegenerative disorder encompassing severe motor symptoms coupled to significant cognitive and social cognition deficits. However, it is not clear whether and how patients' neuropsychological profile changes between the prodromal and the manifest stages of the condition. The aim of the present in-depth review is to consider cognitive and social cognition impairment in HD patients by differentiating deficits arising before diagnosis from those evident from the manifest phase onwards. METHODS: Electronic databases were searched between January 1st , 2010 and December 31st , 2020 by using multiple combinations of keywords related to the investigation of neuropsychological profile in HD for preliminary search, and by defining strict selection criteria for studies to be included. RESULTS: Forty-two studies were included. Evidence suggests that the neuropsychological profile in HD reflects a complex pathological spectrum of deficits. It includes impairment in the realms of executive functions, memory, attention, information processing, and social cognition. Interestingly, patients' profiles differ significantly between the manifest and the prodromal stages of their condition, not only in quantitative terms but also from a qualitative point of view. CONCLUSIONS: Researchers and clinicians should thus include in clinical routine timely and specific neuropsychological assessments in order to monitor patients' cognitive status as time goes by, with the ultimate goal to implement effective clinical management strategies. PRACTITIONER POINTS: The neuropsychological profile in HD encompasses a complex pathological spectrum of deficits. Patients' profiles differ significantly between the manifest and the prodromal stages of their condition. Clinicians should include in everyday practice a timely and specific neuropsychological assessment. Detecting patients' cognitive status during the early stages of the condition already can contribute significantly to implement effective clinical management strategies.

4.
Nat Commun ; 12(1): 6084, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34667149

RESUMO

Postmortem studies have revealed increased density of excitatory synapses in the brains of individuals with autism spectrum disorder (ASD), with a putative link to aberrant mTOR-dependent synaptic pruning. ASD is also characterized by atypical macroscale functional connectivity as measured with resting-state fMRI (rsfMRI). These observations raise the question of whether excess of synapses causes aberrant functional connectivity in ASD. Using rsfMRI, electrophysiology and in silico modelling in Tsc2 haploinsufficient mice, we show that mTOR-dependent increased spine density is associated with ASD -like stereotypies and cortico-striatal hyperconnectivity. These deficits are completely rescued by pharmacological inhibition of mTOR. Notably, we further demonstrate that children with idiopathic ASD exhibit analogous cortical-striatal hyperconnectivity, and document that this connectivity fingerprint is enriched for ASD-dysregulated genes interacting with mTOR or Tsc2. Finally, we show that the identified transcriptomic signature is predominantly expressed in a subset of children with autism, thereby defining a segregable autism subtype. Our findings causally link mTOR-related synaptic pathology to large-scale network aberrations, revealing a unifying multi-scale framework that mechanistically reconciles developmental synaptopathy and functional hyperconnectivity in autism.


Assuntos
Transtorno do Espectro Autista/metabolismo , Transtorno do Espectro Autista/fisiopatologia , Sinapses/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Adolescente , Animais , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/fisiopatologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Criança , Feminino , Haploinsuficiência , Humanos , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Sinapses/genética , Serina-Treonina Quinases TOR/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo
5.
Front Psychol ; 12: 701381, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512458

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has represented an individual and collective trauma with an impact on mental health. Restrictive measures such as lockdowns have increased risk factors for the development or triggering of various psychopathologies. Timely psychological intervention has constituted a protective factor that has been indicated as a form of prevention. The main objective of this study was to measure changes in the levels of traumatic stress and anxiety in a clinical population of adolescents and young adults aged 13 to 24 years - already assisted by the local primary and specialty care services before the pandemic - following a trauma-focused psychotherapeutic group intervention according to the eye movement desensitization and reprocessing protocol, conducted remotely before the end of the first lockdown. The Impact of Event Scale-Revised (IES-R), State-Trait Anxiety Inventory (STAI) scales, and the Emotion Thermometer were administered pre- and post-treatment. At the end of the treatment, the Post-Traumatic Growth Inventory (PTGI) questionnaire was administered. The results show that there was a significant improvement pre- and post-intervention in the scores of the scales STAI, IES-R, and Emotion Thermometer with a reduction in post-traumatic symptoms related in particular to the domains of intrusiveness and hyperarousal. The domain of avoidance was less significantly modified by therapy. This overall clinical improvement did not correlate with any of the demographic variables of the sample. In addition, the results show a significant positive global perceived change (PTGI) that did not correlate with the reduction of anxiety or post-traumatic symptoms measured by the other self-report scales. The explored use of telemedicine has revealed a valuable clinical opportunity.

6.
Eur J Neurol ; 28(3): 745-753, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33175462

RESUMO

BACKGROUND AND PURPOSE: The aim of this study was to evaluate brain metabolic correlates of apathy in amyotrophic lateral sclerosis (ALS). METHODS: A total of 165 ALS patients underwent 18 F-2-fluoro-2-deoxy-D-glucose positron emission tomography (18 F-FDG-PET) and Frontal Systems Behaviour Scale (FrSBe) evaluation. FrSBe provides "before" and "after" apathy subscores, referring to premorbid and morbid conditions. "After" apathy subscore and "before-after" gap, i.e. the difference between "before" and "after" subscores, were regressed against whole-brain metabolism. Among patients with a pathological "after" apathy subscore (i.e., ≥65), we compared patients with "before" apathy subscores ≥65 and <65, and patients with "before-after" gaps of <22 and ≥22. RESULTS: In the whole sample, the "after" apathy subscore negatively correlated with metabolism in the dorsolateral prefrontal cortex (DLPFC), dorsomedial prefrontal cortex (DMPFC), ventrolateral prefrontal cortex (VLPFC), premotor cortex (PMC) and anterior cingulate cortex (ACC), and insula bilaterally. A positive correlation was found in the cerebellum and pons. The "before-after" gap negatively correlated with metabolism in bilateral DLPFC, DMPFC and PMC, and left VLPFC and ACC, and positively correlated with cerebellar and pontine clusters. Among patients with an "after" apathy subscore ≥65, we found no difference between those with "before" apathy subscores ≥65 and <65. Patients with a "before-after" gap ≥22, compared to patients with a gap <22, showed relative hypometabolism in bilateral DLPFC and DMPFC, and left ACC and PMC, and relative cerebellar and pontine hypermetabolism. CONCLUSION: No studies on brain 18 F-2-fluoro-2-deoxy-D-glucose positron emission tomography correlates of apathy have been performed in ALS. We found that FrSBe "after" apathy subscore correlated with metabolic changes in brain regions known as neuroanatomical correlates of apathy. Furthermore, our findings support the relevance of the gap between premorbid and morbid conditions to detect behavioural changes due to the neurodegenerative process underlying ALS.


Assuntos
Esclerose Amiotrófica Lateral , Apatia , Esclerose Amiotrófica Lateral/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Fluordesoxiglucose F18 , Humanos , Tomografia por Emissão de Pósitrons
7.
Eur J Nucl Med Mol Imaging ; 48(4): 1124-1133, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33029654

RESUMO

PURPOSE: To assess the brain metabolic correlates of the different regional extent of ALS, evaluated with the King's staging system, using brain 18F-2-fluoro-2-deoxy-D-glucose-PET (18F-FDG-PET). METHODS: Three hundred ninety ALS cases with King's stages 1, 2, and 3 (n = 390), i.e., involvement of 1, 2, and 3 body regions respectively, underwent brain 18F-FDG-PET at diagnosis. King's stage at PET was derived from ALSFRS-R and was regressed out against whole-brain metabolism in the whole sample. The full factorial design confirmed the hypothesis that differences among groups (King's 1, King's 2, King's 3, and 40 healthy controls (HC)) existed overall. Comparisons among stages and between each group and HC were performed. We included age at PET and sex as covariates. RESULTS: Brain metabolism was inversely correlated with stage in medial frontal gyrus bilaterally, and right precentral and postcentral gyri. The full factorial design resulted in a significant main effect of groups. There was no significant difference between stages 1 and 2. Comparing stage 3 to stage 1+2, a significant relative hypometabolism was highlighted in the former in the left precentral and medial frontal gyri, and in the right medial frontal, postcentral, precentral, and middle frontal gyri. The comparisons between each group and HC showed the extension of frontal metabolic changes from stage 1 to stage 3, with the larger metabolic gap between stages 2 and 3. CONCLUSIONS: Our findings support the hypothesis that in ALS, the propagation of neurodegeneration follows a corticofugal, regional ordered pattern, extending from the motor cortex to posterior and anterior regions.


Assuntos
Esclerose Amiotrófica Lateral , Fluordesoxiglucose F18 , Esclerose Amiotrófica Lateral/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Glucose , Humanos , Tomografia por Emissão de Pósitrons
8.
Neurobiol Aging ; 98: 205-213, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33316576

RESUMO

We tested the Cognitive Reserve (CR) hypothesis in Amyotrophic Lateral Sclerosis (ALS), enrolling 111 patients, using education as CR proxy, 18F-FDG-PET to assess brain damage, and ECAS to measure cognition. Education was regressed out against brain metabolism, including age, sex, spinal/bulbar onset, ALSFRS-R, and ECAS as covariates. Clusters showing a significant correlation were used as seed regions in an interregional correlation analysis (IRCA) in the ALS group and in 40 controls. In the ALS group, we found a negative correlation between brain metabolism and education in the right anterior cingulate and bilateral medial frontal gyrus. In the IRCA in the ALS group, the medial frontal cluster metabolism positively correlated with that of frontotemporal regions (right > left), bilateral caudate nuclei, and right insula, and negatively correlated with that of corticospinal tracts, cerebellum, and pons. In controls, the IRCA showed significant positive correlations in the same regions but less extended. Our results agree with the CR hypothesis. The negative correlation between the medial frontal cluster and the cerebellum found only in ALS patients might reflect cerebellar compensation.


Assuntos
Esclerose Amiotrófica Lateral/complicações , Esclerose Amiotrófica Lateral/psicologia , Encéfalo/metabolismo , Disfunção Cognitiva/etiologia , Reserva Cognitiva , Escolaridade , Esclerose Amiotrófica Lateral/diagnóstico por imagem , Esclerose Amiotrófica Lateral/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Dano Encefálico Crônico/diagnóstico por imagem , Dano Encefálico Crônico/etiologia , Dano Encefálico Crônico/patologia , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos
9.
Sci Adv ; 6(51)2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33355124

RESUMO

Fine-grained descriptions of brain connectivity are required to understand how neural information is processed and relayed across spatial scales. Previous investigations of the mouse brain connectome have used discrete anatomical parcellations, limiting spatial resolution and potentially concealing network attributes critical to connectome organization. Here, we provide a voxel-level description of the network and hierarchical structure of the directed mouse connectome, unconstrained by regional partitioning. We report a number of previously unappreciated organizational principles in the mammalian brain, including a directional segregation of hub regions into neural sink and sources, and a strategic wiring of neuromodulatory nuclei as connector hubs and critical orchestrators of network communication. We also find that the mouse cortical connectome is hierarchically organized along two superimposed cortical gradients reflecting unimodal-transmodal functional processing and a modality-specific sensorimotor axis, recapitulating a phylogenetically conserved feature of higher mammals. These findings advance our understanding of the foundational wiring principles of the mammalian connectome.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33229451

RESUMO

OBJECTIVE: To identify the metabolic changes related to the various levels of cognitive deficits in amyotrophic lateral sclerosis (ALS) using 18F-2-fluoro-2-deoxy-D-glucose positron emission tomography (18F-FDG-PET) imaging. METHODS: 274 ALS patients underwent neuropsychological assessment and brain 18F-FDG-PET at diagnosis. According to the criteria published in 2017, cognitive status was classified as ALS with normal cognition (ALS-Cn, n=132), ALS with behavioural impairment (ALS-Bi, n=66), ALS with cognitive impairment (ALS-Ci, n=30), ALS with cognitive and behavioural impairment (ALS-Cbi, n=26), ALS with frontotemporal dementia (ALS-FTD, n=20). We compared each group displaying some degree of cognitive and/or behavioural impairment to ALS-Cn patients, including age at PET, sex and ALS Functional Rating Scale-Revised as covariates. RESULTS: We identified frontal lobe relative hypometabolism in cognitively impaired patients that resulted more extensive and significant across the continuum from ALS-Ci, through ALS-Cbi, to ALS-FTD. ALS-FTD patients also showed cerebellar relative hypermetabolism. ALS-Bi patients did not show any difference compared with ALS-Cn. CONCLUSIONS: These data support the concept that patients with cognitive impairment have a more widespread neurodegenerative process compared with patients with a pure motor disease: the more severe the cognitive impairment, the more diffuse the metabolic changes. Otherwise, metabolic changes related to pure behavioural impairment need further characterisation.

11.
Front Syst Neurosci ; 14: 569108, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33132856

RESUMO

Conditioning, extinction, and reinstatement are fundamental learning processes of animal adaptation, also strongly involved in human pathologies such as post-traumatic stress disorder, anxiety, depression, and dependencies. Cued fear conditioning, extinction, restatement, and systematic manipulations of the underlying brain amygdala and medial prefrontal cortex, represent key experimental paradigms to study such processes. Numerous empirical studies have revealed several aspects and the neural systems and plasticity underlying them, but at the moment we lack a comprehensive view. Here we propose a computational model based on firing rate leaky units that contributes to such integration by accounting for 25 different experiments on fear conditioning, extinction, and restatement, on the basis of a single neural architecture having a structure and plasticity grounded in known brain biology. This allows the model to furnish three novel contributions to understand these open issues: (a) the functioning of the central and lateral amygdala system supporting conditioning; (b) the role played by the endocannabinoids system in within- and between-session extinction; (c) the formation of three important types of neurons underlying fear processing, namely fear, extinction, and persistent neurons. The model integration of the results on fear conditioning goes substantially beyond what was done in previous models.

12.
Neurobiol Aging ; 96: 117-127, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33002765

RESUMO

From previous studies in healthy volunteers the prefrontal regions are deeply involved in prospective memory (PM), although little is known about the functional neural basis of PM in prodromal Alzheimer's disease (AD). To this end, we retrospectively recruited 18 patients with mild cognitive impairment caused by AD and 23 matched healthy control subjects who had undergone 18F-fluorodeoxyglucose positron emission tomography and the PM-specific paradigm test. Brain metabolism was correlated with the PM score in the 2 groups separately to find those brain areas correlated with PM performance, which were then used as a hub for an inter-regional metabolic connectivity analyses (inter-regional correlation analysis). Of note, in mild cognitive impairment caused by AD, but not in healthy control subjects, PM score positively correlated with metabolic levels in the right anterior prefrontal cortex (middle and inferior frontal gyri), which disclosed a loss of interhemispheric connectivity in the inter-regional correlation analysis. According to our findings, the functioning of the right anterior prefrontal cortex and its interhemispheric metabolic connectivity is crucial in early AD to sustain PM performance, which deteriorates along with progressive metabolic failure of the interconnected areas.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/psicologia , Diagnóstico Precoce , Memória Episódica , Tomografia por Emissão de Pósitrons/métodos , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Idoso , Doença de Alzheimer/metabolismo , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Córtex Pré-Frontal/metabolismo , Compostos Radiofarmacêuticos , Estudos Retrospectivos
13.
Brain Sci ; 10(9)2020 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-32961718

RESUMO

(1) Background: Cognitive features of patients with amyotrophic lateral sclerosis (ALS) have never been specifically analyzed according to the lateralization of motor impairment. In the present study we investigated the cognitive performances of ALS patients to describe the relationship between motor and cognitive dysfunction, according to site and side of disease onset. (2) Methods: Six-hundred and nine ALS patients underwent a comprehensive neuropsychological evaluation at diagnosis in Turin ALS Centre Tests included-mini-mental state examination (MMSE), frontal assessment battery (FAB), trail-making test A/B (TMT A-B), digit span forward and backward (digit span FW/digit span BW), letter fluency test (FAS), category fluency test (CAT), Rey auditory verbal learning test (RAVLT), Babcock story recall test (BSRT), Rey-Osterrieth complex figure test (ROCFT), Wisconsin card sorting test (WCST), Raven's coloured progressive matrices (CPM47). Cognitive performances of patients, grouped by side and site of onset, were statistically compared using z-scores, as appropriate. (3) Results: Bulbar patients and bilateral spinal onset patients (Sbil) were generally characterized by lower cognitive performances in most neuropsychological tests, when compared to patients with lateralized onset (right-side spinal onset, Sri and left-side spinal onset, Sle). Digit span backward and visual memory task (ROCFT) median z-scores were significantly higher, reflecting a better cognitive performance, in Sri patients when compared to bulbar/Sbil patients, while verbal memory tasks (RAVLT and BRST) resulted in significantly higher scores in Sle patients. Our results are in keeping with hemispheric functional lateralization of language and visuospatial abilities. (4) Conclusions: In ALS patients, as in other neurodegenerative diseases, we found a direct relationship between lateralized motor and cognitive features.

14.
Mov Disord ; 35(11): 2009-2018, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32822512

RESUMO

It remains unclear whether the supportive imaging features described in the diagnostic criteria for progressive supranuclear palsy (PSP) are suitable for the full clinical spectrum. The aim of the current study was to define and cross-validate the pattern of glucose metabolism in the brain associated with a diagnosis of different PSP variants. A retrospective multicenter cohort study performed on 73 PSP patients who were referred for a fluorodeoxyglucose positron emission tomography PET scan: PSP-Richardson's syndrome, n = 47; PSP-parkinsonian variant, n = 18; and progressive gait freezing, n = 8. In addition, we included 55 healthy controls and 58 Parkinson's disease (PD) patients. Scans were normalized by global mean activity. We analyzed the regional differences in metabolism between the groups. Moreover, we applied a multivariate analysis to obtain a PSP-related pattern that was cross-validated in independent populations at the individual level. Group analysis showed relative hypometabolism in the midbrain, basal ganglia, thalamus, and frontoinsular cortices and hypermetabolism in the cerebellum and sensorimotor cortices in PSP patients compared with healthy controls and PD patients, the latter with more severe involvement in the basal ganglia and occipital cortices. The PSP-related pattern obtained confirmed the regions described above. At the individual level, the PSP-related pattern showed optimal diagnostic accuracy to distinguish between PSP and healthy controls (sensitivity, 80.4%; specificity, 96.9%) and between PSP and PD (sensitivity, 80.4%; specificity, 90.7%). Moreover, PSP-Richardson's syndrome and PSP-parkinsonian variant patients showed significantly more PSP-related pattern expression than PD patients and healthy controls. The glucose metabolism assessed by fluorodeoxyglucose PET is a useful and reproducible supportive diagnostic tool for PSP-Richardson's syndrome and PSP-parkinsonian variant. © 2020 International Parkinson and Movement Disorder Society.


Assuntos
Transtornos dos Movimentos , Paralisia Supranuclear Progressiva , Encéfalo/diagnóstico por imagem , Estudos de Coortes , Humanos , Estudos Retrospectivos , Paralisia Supranuclear Progressiva/diagnóstico por imagem
15.
Neuroimage Clin ; 27: 102312, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32622315

RESUMO

OBJECTIVE: To evaluate the metabolic correlates of lifetime sport practice in ALS through brain 18F-FDG-PET. METHODS: 131 patients completed a questionnaire about lifetime exposures, including physical activity related to sports, hobbies and occupations, and underwent brain 18F-FDG-PET. Exposure to sports was expressed as MET (Metabolic Equivalent of Task). We considered only regular practice (at least 2 h/week, for at least three months). We compared brain metabolism between two groups: subjects who did not report regular sport practice during life (N-group) and patients who did (Y-group). The resulting significant clusters were used in each group as seed regions in an interregional correlation analysis (IRCA) to evaluate the impact of lifetime sport practice on brain networks typically involved by the neurodegenerative process of ALS. Each group was compared to healthy controls (HC, n = 40). RESULTS: We found a significant, relative cerebellar hypermetabolism in the N-group compared to the Y-group. The metabolism of such cerebellar cluster resulted correlated to more significant and widespread metabolic changes in areas known to be affected by ALS (i.e. frontotemporal regions and corticospinal tracts) in the N-group as compared to the Y-group, despite the same level of disability as expressed by the ALS FRS-R. Such findings resulted independent of age, sex, site of onset (bulbar/spinal), presence/absence of C9ORF72 expansion, cognitive status and physical activity related to hobbies and occupations. When compared to HC, the N-group showed more widespread metabolic changes than the Y-group in cortical regions known to be relatively hypometabolic in ALS patients as compared to HC. CONCLUSIONS: We hypothesize that patients of the N-group might cope better with the neurodegenerative process, since they show more widespread metabolic changes as compared to the Y-group, despite the same level of disability. Nevertheless, further studies are necessary to corroborate this hypothesis.


Assuntos
Esclerose Amiotrófica Lateral , Esclerose Amiotrófica Lateral/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Fluordesoxiglucose F18 , Humanos
16.
JAMA Neurol ; 77(8): 1008-1017, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32421156

RESUMO

Importance: During a time with the potential for novel treatment strategies, early detection of disease manifestations at an individual level in presymptomatic carriers of a hexanucleotide repeat expansion in the C9orf72 gene (preSxC9) is becoming increasingly relevant. Objectives: To evaluate changes in glucose metabolism before symptom onset of amyotrophic lateral sclerosis or frontotemporal dementia in preSxC9 using simultaneous fluorine 18-labeled fluorodeoxyglucose ([18F]FDG positron emission tomographic (PET) and magnetic resonance imaging as well as the mutation's association with clinical and fluid biomarkers. Design, Setting, and Participants: A prospective, case-control study enrolled 46 participants from November 30, 2015, until December 11, 2018. The study was conducted at the neuromuscular reference center of the University Hospitals Leuven, Leuven, Belgium. Main Outcomes and Measures: Neuroimaging data were spatially normalized and analyzed at the voxel level at a height threshold of P < .001, cluster-level familywise error-corrected threshold of P < .05, and statistical significance was set at P < .05 for the volume-of-interest level analysis, using Benjamini-Hochberg correction for multiple correction. W-score maps were computed using the individuals serving as controls as a reference to quantify the degree of [18F]FDG PET abnormality. The threshold for abnormality on the W-score maps was designated as an absolute W-score greater than or equal to 1.96. Neurofilament levels and performance on cognitive and neurologic examinations were determined. All hypothesis tests were 1-sided. Results: Of the 42 included participants, there were 17 with the preSxC9 mutation (12 women [71%]; mean [SD] age, 51 [9] years) and 25 healthy controls (12 women [48%]; mean [SD] age, 47 [10] years). Compared with control participants, significant clusters of relative hypometabolism were found in frontotemporal regions, basal ganglia, and thalami of preSxC9 participants and relative hypermetabolism in the peri-Rolandic region, superior frontal gyrus, and precuneus cortex. W-score frequency maps revealed reduced glucose metabolism with local maxima in the insular cortices, central opercular cortex, and thalami in up to 82% of preSxC9 participants and increased glucose metabolism in the precentral gyrus and precuneus cortex in up to 71% of preSxC9 participants. Other findings in the preSxC9 group were upper motor neuron involvement in 10 participants (59%), cognitive abnormalities in 5 participants (29%), and elevated neurofilament levels in 3 of 16 individuals (19%) who underwent lumbar puncture. Conclusions and Relevance: The results suggest that [18F]FDG PET can identify glucose metabolic changes in preSxC9 at an individual level, preceding significantly elevated neurofilament levels and onset of symptoms.


Assuntos
Esclerose Amiotrófica Lateral/diagnóstico , Proteína C9orf72/genética , Córtex Cerebral/diagnóstico por imagem , Demência Frontotemporal/diagnóstico , Tomografia por Emissão de Pósitrons/normas , Sintomas Prodrômicos , Adulto , Idoso , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/metabolismo , Esclerose Amiotrófica Lateral/patologia , Biomarcadores , Estudos de Casos e Controles , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Expansão das Repetições de DNA , Feminino , Fluordesoxiglucose F18 , Demência Frontotemporal/genética , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Heterozigoto , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Estudos Prospectivos
17.
Artigo em Inglês | MEDLINE | ID: mdl-32397541

RESUMO

Neuroscientific research has largely investigated the neurobiological correlates of maternal and (to a much lesser extent) paternal responsiveness in the post-partum period. In contrast, much less is known about the neural processing of infant emotions during pregnancy. Twenty mothers and 19 fathers were recruited independently during the third trimester of pregnancy. High-density electroencephalography (hdEEG) was recorded while expectant parents passively viewed images representing distressed, ambiguous, happy, and neutral faces of unknown infants. Correlational analyses were performed to detect a link between neural responses to infant facial expressions and emotional self-awareness. In response to infant emotions, mothers and fathers showed similar cerebral activity in regions involved in high-order socio-affective processes. Mothers and fathers also showed different brain activity in premotor regions implicated in high-order motor control, in occipital regions involved in visuo-spatial information processing and visual mental imagery, as well as in inferior parietal regions involved in attention allocation. Low emotional self-awareness negatively correlated with activity in parietal regions subserving empathy in mothers, while it positively correlated with activity in temporal and occipital areas implicated in mentalizing and visual mental imagery in fathers. This study may enlarge knowledge on the neural response to infant emotions during pregnancy.


Assuntos
Emoções , Expressão Facial , Psicologia da Criança , Atenção , Pai , Feminino , Humanos , Lactente , Masculino , Mães , Gravidez , Autoimagem
18.
Neuroscience ; 445: 83-94, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31917352

RESUMO

Central release of the neuropeptide oxytocin (OXT) modulates neural substrates involved in socio-affective behavior. This property has prompted research into the use of intranasal OXT administration as an adjunctive therapy for brain conditions characterized by social impairment, such as autism spectrum disorders (ASD). However, the neural circuitry and brain-wide functional networks recruited by intranasal OXT administration remain elusive. Moreover, little is known of the neuroadaptive cascade triggered by long-term administration of this peptide at the network level. To address these questions, we applied fMRI-based circuit mapping in adult mice upon acute and repeated (seven-day) intranasal dosing of OXT. We report that acute and chronic OXT administration elicit comparable fMRI activity as assessed with cerebral blood volume mapping, but entail largely different patterns of brain-wide functional connectivity. Specifically, acute OXT administration focally boosted connectivity within key limbic components of the rodent social brain, whereas repeated dosing led to a prominent and widespread increase in functional connectivity, involving a strong coupling between the amygdala and extended cortical territories. Importantly, this connectional reconfiguration was accompanied by a paradoxical reduction in social interaction and communication in wild-type mice. Our results identify the network substrates engaged by exogenous OXT administration, and show that repeated OXT dosing leads to a substantial reconfiguration of brain-wide connectivity, entailing an aberrant functional coupling between cortico-limbic structures involved in socio-communicative and affective functions. Such divergent patterns of network connectivity might contribute to discrepant clinical findings involving acute or long-term OXT dosing in clinical populations.


Assuntos
Encéfalo , Ocitocina , Administração Intranasal , Tonsila do Cerebelo , Animais , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Camundongos
19.
Eur J Nucl Med Mol Imaging ; 47(2): 437-450, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31768600

RESUMO

RATIONALE: In Parkinson's disease (PD), spatial covariance analysis of 18F-FDG PET data has consistently revealed a characteristic PD-related brain pattern (PDRP). By quantifying PDRP expression on a scan-by-scan basis, this technique allows objective assessment of disease activity in individual subjects. We provide a further validation of the PDRP by applying spatial covariance analysis to PD cohorts from the Netherlands (NL), Italy (IT), and Spain (SP). METHODS: The PDRPNL was previously identified (17 controls, 19 PD) and its expression was determined in 19 healthy controls and 20 PD patients from the Netherlands. The PDRPIT was identified in 20 controls and 20 "de-novo" PD patients from an Italian cohort. A further 24 controls and 18 "de-novo" Italian patients were used for validation. The PDRPSP was identified in 19 controls and 19 PD patients from a Spanish cohort with late-stage PD. Thirty Spanish PD patients were used for validation. Patterns of the three centers were visually compared and then cross-validated. Furthermore, PDRP expression was determined in 8 patients with multiple system atrophy. RESULTS: A PDRP could be identified in each cohort. Each PDRP was characterized by relative hypermetabolism in the thalamus, putamen/pallidum, pons, cerebellum, and motor cortex. These changes co-varied with variable degrees of hypometabolism in posterior parietal, occipital, and frontal cortices. Frontal hypometabolism was less pronounced in "de-novo" PD subjects (Italian cohort). Occipital hypometabolism was more pronounced in late-stage PD subjects (Spanish cohort). PDRPIT, PDRPNL, and PDRPSP were significantly expressed in PD patients compared with controls in validation cohorts from the same center (P < 0.0001), and maintained significance on cross-validation (P < 0.005). PDRP expression was absent in MSA. CONCLUSION: The PDRP is a reproducible disease characteristic across PD populations and scanning platforms globally. Further study is needed to identify the topography of specific PD subtypes, and to identify and correct for center-specific effects.


Assuntos
Doença de Parkinson , Encéfalo/diagnóstico por imagem , Fluordesoxiglucose F18 , Glucose , Humanos , Itália , Países Baixos , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Espanha
20.
Mov Disord ; 35(4): 587-594, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31872507

RESUMO

BACKGROUND: An ideal imaging biomarker for a neurodegenerative disorder should be able to measure abnormalities in the earliest stages of the disease. OBJECTIVE: We investigated metabolic network changes in two independent cohorts of drug-naïve Parkinson's disease (PD) patients who have not been exposed to dopaminergic medication. METHODS: We scanned 85 de novo, drug-naïve PD patients and 85 age-matched healthy control subjects from Italy (n = 96) and the United States (n = 74) with [18 F]-fluorodeoxyglucose PET. All patients had clinical follow-ups to verify the diagnosis of idiopathic PD. Spatial covariance analysis was used to identify and validate de novo PD-related metabolic patterns in the Italian and U.S. cohorts. We compared the de novo PD-related metabolic patterns to the original PD-related pattern that was identified in more advanced patients who had been on chronic dopaminergic treatment. RESULTS: De novo PD-related metabolic patterns were identified in each of the two independent cohorts of drug-naïve PD patients, and each differentiated PD patients from healthy control subjects. Expression values for these disease patterns were elevated in drug-naïve PD patients relative to healthy controls in the identification as well as in each of the validation subgroups. The two de novo PD-related metabolic patterns were topographically very similar to each other and to the original PD-related pattern. CONCLUSIONS: Reproducible PD-related patterns are expressed in de novo, drug-naïve PD patients. In PD, disease-related metabolic patterns have stereotyped topographies that develop independently of chronic levodopa treatment. © 2019 International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , Preparações Farmacêuticas , Humanos , Itália , Levodopa , Redes e Vias Metabólicas , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/tratamento farmacológico
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