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1.
Dev Med Child Neurol ; 62(1): 125-131, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31393613

RESUMO

AIM: To examine if congenital visual impairment is associated with differences in brain anatomy in children. METHOD: Ten children (8-12y) with congenital disorders of the peripheral visual system with severe visual impairment (SVI; >0.8 logMAR) or mild-to-moderate visual impairment (MVI; 0.6-0.8 logMAR) were compared to 21 typically sighted comparison (TSC) children. Thalamus volume, grey matter density, white matter microstructure, and integrity of visual tracts were investigated in SVI, MVI, and TSC groups with anatomical and diffusion-weighted magnetic resonance imaging. RESULTS: Compared to the TSC group, the SVI group had lower white matter integrity in tracts of the visual system (optic radiations: SVI 0.35±0.015, TSC 0.39±0.007 [p=0.022]; posterior corpus callosum: SVI 0.37±0.019; TSC 0.42±0.009 [p=0.033]) and lower left thalamus volume (SVI 4.37±0.087; TSC 4.99±0.339 [p=0.015]). Neuroanatomical differences were greater in the SVI group, while no consistent differences between the MVI and TSC group were observed. INTERPRETATION: Posterior tracts of the visual system are compromised in children with congenital visual impairment versus those who are typically sighted. The severity of visual input appears to have affected neuroanatomical development as significant reductions were only found in the SVI group. WHAT THIS PAPER ADDS: Severe visual impairment in mid-childhood is associated with reduced integrity of visual pathways and reduced thalamus volume.


Assuntos
Corpo Caloso/patologia , Tálamo/patologia , Transtornos da Visão/congênito , Transtornos da Visão/patologia , Vias Visuais/patologia , Substância Branca/patologia , Criança , Corpo Caloso/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Índice de Gravidade de Doença , Tálamo/diagnóstico por imagem , Transtornos da Visão/diagnóstico por imagem , Vias Visuais/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
2.
Immunity ; 52(1): 167-182.e7, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31883839

RESUMO

Multiple sclerosis (MS) is a demyelinating, autoimmune disease of the central nervous system. While work has focused on myelin and axon loss in MS, less is known about mechanisms underlying synaptic changes. Using postmortem human MS tissue, a preclinical nonhuman primate model of MS, and two rodent models of demyelinating disease, we investigated synapse changes in the visual system. Similar to other neurodegenerative diseases, microglial synaptic engulfment and profound synapse loss were observed. In mice, synapse loss occurred independently of local demyelination and neuronal degeneration but coincided with gliosis and increased complement component C3, but not C1q, at synapses. Viral overexpression of the complement inhibitor Crry at C3-bound synapses decreased microglial engulfment of synapses and protected visual function. These results indicate that microglia eliminate synapses through the alternative complement cascade in demyelinating disease and identify a strategy to prevent synapse loss that may be broadly applicable to other neurodegenerative diseases. VIDEO ABSTRACT.


Assuntos
Complemento C3/imunologia , Encefalomielite Autoimune Experimental/patologia , Microglia/patologia , Esclerose Múltipla/patologia , Sinapses/patologia , Tálamo/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Callithrix , Linhagem Celular Tumoral , Complemento C3/antagonistas & inibidores , Modelos Animais de Doenças , Feminino , Gliose/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Receptores de Complemento 3b/metabolismo
3.
Medicine (Baltimore) ; 98(40): e17127, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31577703

RESUMO

To investigate the functional connectome alterations in cerebral small-vessel disease (CSVD) patients with thalamus lacunes and its relation to cognitive impairment.This case-control study was approved by the local research ethics committee, and all participants provided informed consent. There were 14 CSVD patients with thalamus lacunes (CSVDw.), 27 without (CSVDwo.), and 34 healthy controls (HC) recruited matched for age, sex, and education to undergo a 3T resting-state functional MR examination. The whole-brain functional connectome was constructed by thresholding the Pearson correlation matrices of 90 brain regions, and the topologic properties were analyzed by using graph theory approaches. Networks were compared between CSVD patients and HC, and associations between network measures and cognitive function were tested.Compared with HC, the functional connectome in CSVDw. patients showed abnormalities at the global level and at the nodal level (P < .05, false discovery rate corrected). The network-based statistics method identified a significantly altered network consisting 6 nodes and 13 connections. Among all the 13 connections, only two connections had significant correlation with episodic memory (EM) and processing speed (PS) respectively (P < .05). The CSVDwo. patients showed no significant network alterations relative to controls (P > .05).The configurations of brain functional connectome in CSVDw. patients were perturbed but not obvious for those without, and correlated with the mild cognitive impairment, especially for EM and PS. This study suggested that lacunes on thalamus played a vital role in mediating the neural functional changes of CSVD patients.


Assuntos
Doenças de Pequenos Vasos Cerebrais/patologia , Disfunção Cognitiva/patologia , Conectoma , Leucoencefalopatias/patologia , Tálamo/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Estudos Transversais , Escolaridade , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Leucoencefalopatias/complicações , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Índice de Gravidade de Doença , Fatores Sexuais , Tálamo/diagnóstico por imagem
4.
Phys Rev E ; 100(3-1): 032405, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31639915

RESUMO

Absence epilepsy is characterized by a sudden paroxysmal loss of consciousness accompanied by oscillatory activity propagating over many brain areas. Although primary generalized absence seizures are supported by the global corticothalamic system, converging experimental evidence supports a focal theory of absence epilepsy. Here a physiology-based corticothalamic model is investigated with spatial heterogeneity due to focal epilepsy to unify global and focal aspects of absence epilepsy. Numeric and analytic calculations are employed to investigate the emergent spatiotemporal dynamics as well as their underlying dynamical mechanisms. They can be categorized into three scenarios: suppressed epilepsy, focal seizures, or generalized seizures, as summarized from a phase diagram vs focal width and characteristic axon range. The corresponding temporal frequencies and spatial extents of cortical waves in generalized seizures and focal seizures agree well with experimental observations of global and focal aspects of absence epilepsy, respectively. The emergence of the spatiotemporal dynamics corresponding to focal seizures provides a biophysical explanation of the temporally higher frequency but spatially more localized cortical waves observed in genetic rat models that display characteristics of human absence epilepsy. Predictions are also presented for further experimental test.


Assuntos
Córtex Cerebral/patologia , Epilepsia Tipo Ausência/patologia , Modelos Neurológicos , Tálamo/patologia , Animais , Humanos , Ratos
5.
Eur J Radiol ; 119: 108620, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31422164

RESUMO

PURPOSE: This study aimed to evaluate the amide proton transfer (APT) values in neonates with mild hypoxic-ischemic encephalopathy (HIE) using APT imaging. METHOD: A total of 30 full-term neonates with mild HIE (16 males and 14 females; mean postnatal age 4.2 days, age range 2-7 days) and 12 normal neonates (six males and six females; mean postnatal age 3.3 days, age range 2-5 days) underwent conventional magnetic resonance imaging and APT imaging. APT measurements were performed in multiple regions of interest (ROIs) in the brain. APT values were statistically analyzed to assess for significant differences between the mild HIE and normal neonates in different regions of the brain, and correlation with neonatal gestational age. RESULTS: In 30 neonates with mild HIE, 10% (3/30) of the HIE patients had normal conventional MRI. There were significant differences in APT values of the HIE group in bilateral caudate, bilateral thalamus, bilateral centrum semiovale and left globus pallidus/putamen (p < 0.05), and no statistical difference was observed in right globus pallidus/putamen (p = 0.051) and brainstem (p = 0.073) between the two groups. Furthermore, APT values in bilateral caudate, bilateral globus pallidus/putamen, bilateral thalamus, and brainstem regions (p < 0.05) exhibited positive linear correlations with gestational age in the control group, except for bilateral centrum semiovale (right: Pearson's r = 0.554, p = 0.062; left: Pearson's r = 0.561, p = 0.058). In the mild HIE groups, no significant correlation with gestational age was found in all regions. CONCLUSIONS: APT imaging is a feasible and useful technique with diagnostic capability for neonatal HIE.


Assuntos
Amidas , Hipóxia-Isquemia Encefálica/patologia , Imagem por Ressonância Magnética/métodos , Prótons , Encéfalo/patologia , Estudos de Casos e Controles , Criança , Diagnóstico Precoce , Estudos de Viabilidade , Feminino , Idade Gestacional , Humanos , Hipóxia-Isquemia Encefálica/congênito , Recém-Nascido , Masculino , Projetos Piloto , Medição de Risco , Tálamo/patologia
6.
J Clin Neurosci ; 68: 168-173, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31324472

RESUMO

The aim of this study was to compare brain volume reduction in patients with Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) with age-related changes in age- and gender-matched healthy individuals. Sixty-six patients were divided in three groups based on medical history, neurological and neurocognitive assessment: 26 patients with AD, 20 patients with aMCI and 20 healthy controls. All participants underwent high-resolution magnetic resonance (MR) imaging on 3 T unit. MR volumetry of cerebral cortex, white matter and lateral ventricles volumes, as well as volumes of subcortical nuclei (hippocampus, amygdala, thalamus) was performed. Global cerebral and grey matter volumes were lower in AD patients compared to aMCI (p = 0.023 and p = 0.001, respectively) and controls (p < 0.001 and p < 0.001, respectively). Volume of lateral ventricles was significantly higher in AD patients compared to controls (right p = 0.007, left p = 0.007). Volumes of thalamus were lower in AD patients (right p < 0.001, left p < 0.001), and in aMCI patients (right p = 0.004, left p = 0.015), compared to controls. Hippocampal volume was lower in AD patients compared to both aMCI patients (right p = 0.047, left p = 0.003) and controls (right p < 0.001, left p < 0.001). In aMCI patients, hippocampal volume was lower than in controls (right p = 0.004, left p = 0.007). Volumes of amygdala were lower in AD patients compared to controls (righ p = 0.003, left p = 0.001). Our results show that thalamic volume loss could be an early sign associated with poorercognitiveperformance in aMCI, preceeding the atrophy of amygdala, global grey and white matter volume loss, and cerebrospinal fluid spaces dilatation.


Assuntos
Doença de Alzheimer/patologia , Disfunção Cognitiva/patologia , Tálamo/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
7.
Pan Afr Med J ; 33: 2, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303947

RESUMO

Ischemic stroke can result from multiple etiologies. It can also be a complication of tuberculous meningoencephalitis and determine its outcome. stroke secondary to tuberculous meningoencephalitis, occurs in 30% cases in the basal ganglia region, unusually in the thalamus. The mechanism of stroke in this condition is vasculitis. We report an unusual case of bilateral thalamic infarcts complicating tuberculous meningoencephalitis. Ischemic stroke in tuberculous meningoencephalitis is unpredictable with poor prognosis despite antituberculous drug treatment, emphasising the importance of primary prevention, particularly in tuberculosis endemic areas.


Assuntos
Infarto Encefálico/etiologia , Meningoencefalite/complicações , Acidente Vascular Cerebral/etiologia , Tuberculose Meníngea/complicações , Adolescente , Antituberculosos/administração & dosagem , Infarto Encefálico/diagnóstico , Humanos , Masculino , Meningoencefalite/tratamento farmacológico , Meningoencefalite/microbiologia , Prognóstico , Acidente Vascular Cerebral/diagnóstico , Tálamo/patologia , Tuberculose Meníngea/tratamento farmacológico
8.
PLoS One ; 14(5): e0217922, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31150514

RESUMO

To meet the need for Parkinson's disease biomarkers and evidence for amount and distribution of pathological changes, MRI diffusion tensor imaging (DTI) has been explored in a number of previous studies. However, conflicting results warrant further investigations. As tissue microstructure, particularly of the grey matter, is heterogeneous, a more precise diffusion model may benefit tissue characterization. The purpose of this study was to analyze the diffusion-based imaging technique restriction spectrum imaging (RSI) and DTI, and their ability to detect microstructural changes within brain regions associated with motor function in Parkinson's disease. Diffusion weighted (DW) MR images of a total of 100 individuals, (46 Parkinson's disease patients and 54 healthy controls) were collected using b-values of 0-4000s/mm2. Output diffusion-based maps were estimated based on the RSI-model combining the full set of DW-images (Cellular Index (CI), Neurite Density (ND)) and DTI-model combining b = 0 and b = 1000 s/mm2 (fractional anisotropy (FA), Axial-, Mean- and Radial diffusivity (AD, MD, RD)). All parametric maps were analyzed in a voxel-wise group analysis, with focus on typical brain regions associated with Parkinson's disease pathology. CI, ND and DTI diffusivity metrics (AD, MD, RD) demonstrated the ability to differentiate between groups, with strongest performance within the thalamus, prone to pathology in Parkinson's disease. Our results indicate that RSI may improve the predictive power of diffusion-based MRI, and provide additional information when combined with the standard diffusivity measurements. In the absence of major atrophy, diffusion techniques may reveal microstructural pathology. Our results suggest that protocols for MRI diffusion imaging may be adapted to more sensitive detection of pathology at different sites of the central nervous system.


Assuntos
Diagnóstico por Imagem , Imagem de Tensor de Difusão , Degeneração Neural/diagnóstico , Doença de Parkinson/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Tronco Encefálico/diagnóstico por imagem , Tronco Encefálico/patologia , Imagem de Difusão por Ressonância Magnética , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Degeneração Neural/diagnóstico por imagem , Degeneração Neural/patologia , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Tálamo/diagnóstico por imagem , Tálamo/patologia
9.
Medicina (B Aires) ; 79(2): 111-114, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31048276

RESUMO

The purpose of this study was to combine two automated methods of magnetic resonance imaging (MRI) structural analysis in order to identify structural changes in patients born in Argentina with idiopathic generalized epilepsy (IGE) compared to a healthy adult control group. Twenty-eight patients with IGE and 26 controls with no significant demographic differences were included. The analysis of the brain structures was conducted with two automated methods of magnetic resonance image analysis: voxelbased morphometry and FSL-integrated registration and segmentation toolbox (FSL-FIRST). FSL showed volume decrease in both thalamus in patients with IGE compared to the control group (left: 8092 mm3 control group vs. 7424 mm3 IGE, p = 0.0015; right: 7951 mm3 control group vs. 7247 mm3 IGE, p = 0.0016). A reduction in the volume of both caudate nuclei was also seen (left: 3612 mm3 control group vs. 3376 mm3 IGE, p = 0.01; right: 3683 mm3 control group vs. 3459 mm3 IGE, p = 0.04). Voxel-based-morphometry showed a volume decrease in both caudate nuclei in patients with IGE compared to the control group. The other cerebral structures analyzed did not show significant differences between the groups. In conclusion, this study shows the reduction in volume in the subcortical, thalamic, and caudate nuclei structures in patients with IGE in comparison to control group. This study conducted in our country delves into the analysis of brain structural changes in patients with EGI compared to healthy subjects.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Epilepsia Generalizada/diagnóstico por imagem , Epilepsia Generalizada/patologia , Imagem por Ressonância Magnética/métodos , Adulto , Análise de Variância , Argentina , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Tamanho do Órgão , Valores de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tálamo/diagnóstico por imagem , Tálamo/patologia
10.
Neurotox Res ; 36(1): 144-162, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31049881

RESUMO

A murine model used to investigate the osmotic demyelination syndrome (ODS) demonstrated ultrastructural damages in thalamus nuclei. Following chronic hyponatremia, significant myelinolysis was merely detected 48 h after the rapid reinstatement of normonatremia (ODS 48 h). In ODS samples, oligodendrocytes and astrocytes revealed injurious changes associated with a few cell deaths while both cell types seemed to endure a sort of survival strategy: (a) ODS 12 h oligodendrocytes displayed nucleoplasm with huge heterochromatic compaction, mitochondria hypertrophy, and most reclaimed an active NN cell aspect at ODS 48 h. (b) Astrocytes responded to the osmotic stress by overall cell shrinkage with clasmatodendrosis, these changes accompanied nucleus wrinkling, compacted and segregated nucleolus, destabilization of astrocyte-oligodendrocyte junctions, loss of typical GFAP filaments, and detection of round to oblong woolly, proteinaceous aggregates. ODS 48 h astrocytes regained an active nucleus aspect, without restituting GFAP filaments and still contained cytoplasmic proteinaceous deposits. (c) Sustaining minor shrinking defects at ODS 12 h, neurons showed slight axonal injury. At ODS 48 h, neuron cell bodies emerged again with deeply indented nucleus and, owing nucleolus translational activation, huge amounts of polysomes along with secretory-like activities. (d) In ODS, activated microglial cells got stuffed with huge lysosome bodies out of captures cell damages, leaving voids in interfascicular and sub-vascular neuropil. Following chronic hyponatremia, the murine thalamus restoration showed macroglial cells acutely turned off transcriptional and translational activities during ODS and progressively recovered activities, unless severely damaged cells underwent cell death, leading to neuropil disruption and demyelination.


Assuntos
Doenças Desmielinizantes/patologia , Pressão Osmótica , Tálamo/patologia , Tálamo/ultraestrutura , Animais , Astrócitos/patologia , Astrócitos/ultraestrutura , Axônios/patologia , Axônios/ultraestrutura , Doenças Desmielinizantes/etiologia , Modelos Animais de Doenças , Hiponatremia/complicações , Hiponatremia/patologia , Masculino , Camundongos Endogâmicos C57BL , Neurônios/patologia , Neurônios/ultraestrutura , Oligodendroglia/patologia , Oligodendroglia/ultraestrutura
11.
BMC Psychiatry ; 19(1): 108, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30953482

RESUMO

BACKGROUND: Based on genome-wide association studies, a single-nucleotide polymorphism in the NRGN gene (rs12807809) is considered associated with schizophrenia (SZ). Moreover, hippocampal dysfunction is associated with rs12807809. In addition, converging evidence suggests that hippocampal dysfunction is involved in SZ pathophysiology. However, the association among rs12807809, hippocampal dysfunction and SZ pathophysiology is unknown. Therefore, this study investigated the association between rs12807809 and hippocampal functional connectivity at rest in SZ. METHODS: In total, 158 participants were studied, including a C-carrier group carrying the non-risk C allele (29 SZ patients and 46 healthy controls) and a TT homozygous group carrying the risk T allele (30 SZ patients and 53 healthy controls). All participants were scanned using resting-state functional magnetic resonance imaging. Hippocampal functional connectivity was computed and compared among the 4 groups. RESULTS: Significant main effects of diagnosis were observed in the functional connectivity between the hippocampus and bilateral fusiform gyrus, bilateral lingual gyrus, left inferior temporal gyrus, left caudate nucleus, bilateral thalamus and bilateral anterior cingulate gyri. In contrast, no significant main effect of genotype was found. In addition, a significant genotype by diagnosis interaction in the functional connectivity between the hippocampus and left anterior cingulate gyrus, as well as bilateral middle cingulate gyri, was observed, with TT homozygotes with SZ showing less functional connectivity than C-carriers with SZ and healthy control TT homozygotes. CONCLUSIONS: These findings are the first to suggest an association between rs12807809 and abnormal Papez circuit function in patients with SZ. This study also implicates NRGN variation and abnormal Papez circuit function in SZ pathophysiology.


Assuntos
Genótipo , Neurogranina/genética , Polimorfismo de Nucleotídeo Único , Esquizofrenia/genética , Esquizofrenia/patologia , Adulto , Alelos , Feminino , Estudo de Associação Genômica Ampla , Giro do Cíngulo/patologia , Hipocampo/patologia , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Lobo Temporal/fisiopatologia , Tálamo/patologia
12.
J Clin Neurosci ; 64: 89-93, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30962057

RESUMO

OBJECTIVES: Obsessive compulsive personality disorder (OCPD) is currently thought to bear a close relationship with obsessive-compulsive disorder (OCD), and other compulsive disorders such as eating disorder and autistic spectrum disorder, as well as with the personality disorders, focusing on some important dimensions like phenomenology, heritability, environmental risk factors, comorbidity, course of illness, neurocognitive endophenotypes, and treatment response. In the present study, when we have taken into consideration the knowledge aforementioned, we aimed to examine OFC and thalamus volumes in patients with OCPD. METHODS: We comparatively measured orbito-frontal cortex (OFC) and thalamus volumes of patients with OCPD and healthy control subjects. RESULTS: Patients with OCPD had considerably smaller left and right OFC volumes compared to those of healthy control subjects. We also found that thalamus volumes of patients were statistically significantly greater than those of healthy comparisons for both sides of region of interest. CONCLUSIONS: We consider that volumetric alterations determined in the present study may be involved in the pathophysiology of the OCPD, considering that OCPD might be related to OCD spectrum disorders neuroanatomically.


Assuntos
Transtorno da Personalidade Compulsiva/diagnóstico por imagem , Transtorno da Personalidade Compulsiva/patologia , Lobo Frontal/patologia , Tálamo/patologia , Adulto , Feminino , Lobo Frontal/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/patologia , Tálamo/diagnóstico por imagem
13.
Neuroimage Clin ; 22: 101791, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30991612

RESUMO

OBJECTIVE: To investigate the structural integrity of fibre tracts underlying overt motor behaviour in PDOC. METHODS: This cross-sectional study examined 15 PDOC patients and 22 healthy participants. Eight PDOC patients met the criteria for the vegetative state, 5 met the criteria for the minimally conscious state and 2 met the criteria for emerging from the minimally conscious state. We used fibre tractography to reconstruct the white matter fibres known to be involved in voluntary motor execution (i.e., those connecting thalamus with M1, M1 with cerebellum, and cerebellum with thalamus) and used fractional anisotropy (FA) as a measure of their integrity. RESULTS: PDOC patients showed significantly reduced FA relative to controls on the fibres connecting thalamus and M1. This went above and beyond a widespread injury to the white matter and correlated with clinical severity. In a subset of patients, we also identified a similar pattern of injury in the fibres connecting M1 and cerebellum but a relative preservation of those connecting cerebellum and thalamus. CONCLUSIONS: Our results suggest that structural damage to motor fibres may lead to reduced responsiveness in PDOC patients across all diagnostic sub-categories, and therefore behavioural assessments may underestimate the level of retained cognitive function and awareness across the PDOC spectrum.


Assuntos
Cerebelo/patologia , Atividade Motora , Córtex Motor/patologia , Estado Vegetativo Persistente/patologia , Tálamo/patologia , Substância Branca/patologia , Adulto , Cerebelo/diagnóstico por imagem , Estudos Transversais , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Fibras Nervosas/patologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/patologia , Estado Vegetativo Persistente/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto Jovem
14.
eNeuro ; 6(2)2019.
Artigo em Inglês | MEDLINE | ID: mdl-30993181

RESUMO

The transition from adolescence to adulthood is associated with brain remodeling in the final stages of developmental growth. It is also a period when a large proportion of this age group engages in binge alcohol drinking (occasional consumption of four to five drinks leading to intoxication) and heavy alcohol drinking (binge drinking on ≥5 d in a month). Here we report on magnetic resonance imaging of developmental changes in the brain occurring during late adolescence and early adulthood (3.5-7.5 years of age) in a rhesus macaque model of alcohol self-administration. Monkeys were imaged prior to alcohol exposure, and following ∼6 and ∼12 months of daily (22 h/d) access to ethanol and water. The results revealed that the brain volume increases by 1 ml/1.87 years throughout the late adolescence and early adulthood in controls. Heavy alcohol drinking reduced the rate of brain growth by 0.25 ml/year per 1 g/kg daily ethanol. Cortical volume increased throughout this period with no significant effect of alcohol drinking on the cortical growth rate. In subcortical regions, age-dependent increases in the volumes of globus pallidus, thalamus, brainstem, and cerebellum were observed. Heavy drinking attenuated the growth rate of the thalamus. Thus, developmental brain volume changes in the span of late adolescence to young adulthood in macaques is altered by excessive alcohol, an insult that may be linked to the continuation of heavy drinking throughout later adult life.


Assuntos
Alcoolismo , Encéfalo , Depressores do Sistema Nervoso Central/efeitos adversos , Etanol/efeitos adversos , Consumo de Álcool por Menores , Fatores Etários , Alcoolismo/complicações , Alcoolismo/diagnóstico por imagem , Alcoolismo/patologia , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/patologia , Modelos Animais de Doenças , Feminino , Macaca mulatta , Imagem por Ressonância Magnética , Masculino , Tálamo/diagnóstico por imagem , Tálamo/efeitos dos fármacos , Tálamo/crescimento & desenvolvimento , Tálamo/patologia
16.
Neuroimage Clin ; 22: 101749, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30875641

RESUMO

BACKGROUND: Cerebral microbleeds (CMBs) are considered to be risk factors for cognitive dysfunction. The specific pathology and clinical manifestations of CMBs are different based on their locations. We investigated the association between CMBs at different locations and cognitive dysfunction and explored the potential underlying pathways in a rural Han Chinese population. METHODS: We used baseline data from 562 community-dwelling adults (55-65 years old) in the Taizhou Imaging Study between 2013 and 2015. All individuals underwent multimodal brain magnetic resonance imaging (MRI) and 444 subjects completed neuropsychological tests: the Mini-Mental Status Examination and the Montreal Cognitive Assessment. Multinomial logistic regression was used to estimate the association between CMBs and cognitive dysfunction. The volume of brain regions and white matter microstructure were analyzed using Freesurfer and tract-based spatial statistics, respectively. RESULTS: CMBs were detected in 104 individuals (18.5%) in our study. Multinomial logistic regression found deep/mixed CMBs were associated with global cognitive dysfunction (OR 3.52; 95% CI 1.21 to 10.26), whereas lobar CMBs (OR 1.76; 95% CI 0.56 to 5.53) were not. Quantification of multimodal brain MRI showed that deep/mixed CMBs were accompanied by decreased thalamic volume and loss of fractional anisotropy of bilateral anterior thalamic radiations. CONCLUSION: Deep/mixed CMBs were associated with cognitive dysfunction in this Chinese cross-sectional study. Disruption of thalamocortical connectivity might be a potential pathway underlying this relationship.


Assuntos
Córtex Cerebral/patologia , Hemorragia Cerebral/patologia , Hemorragia Cerebral/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Tálamo/patologia , Substância Branca/patologia , Idoso , Córtex Cerebral/diagnóstico por imagem , Hemorragia Cerebral/complicações , Hemorragia Cerebral/diagnóstico por imagem , China , Disfunção Cognitiva/etiologia , Estudos Transversais , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tálamo/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
17.
Neuroimage Clin ; 22: 101754, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30921612

RESUMO

OBJECTIVE: Focused ultrasound thalamotomy is an emerging treatment for essential tremor, and it is ideal for studying reorganization in the human brain after acute injury because it creates a controlled thalamic ablation without breaching the cortex. However, there is not yet a metric capable of detecting microstructural changes in the presence of acute phase edema with good sensitivity in the chronic phase, when the lesion boundaries become inconspicuous. METHODS: We prospectively studied microstructural changes at the lesion site using generalized q-sampling imaging with restricted diffusion imaging. We obtained diffusion-weighted MRI scans preoperatively, 1 day after (n = 18), and 1 year after (n = 9) focused ultrasound thalamotomy. The restricted diffusion imaging maps were compared at the group level, controlling for improvement in contralateral hand tremor. RESULTS: The restricted diffusion imaging metric significantly increased in the 1 day post images, and the area with restricted diffusivity extended beyond the lesion boundaries identified on T2-weighted imaging. Two distinct zones of microstructural changes were identified, and the lesion area was identifiable at 1 year. The anterior and medial aspects of the lesion had a significant changes in RDI at 1 year, potentially signifying reorganization. The voxels with significant changes in restricted diffusion imaging values extend beyond the VIM into the surrounding white matter. INTERPRETATION: Correcting for free water contamination with restricted diffusion imaging allowed us to study microstructural changes after focused ultrasound thalamotomy. We observed statistically significant changes in RDI in the anterior and medial aspect of the lesion at 1 year. Whether these changes represent tissue reorganization remains to be confirmed in future studies. These findings may support performing additional ablations antero-medially for durable efficacy.


Assuntos
Tremor Essencial/diagnóstico por imagem , Tremor Essencial/cirurgia , Tálamo/patologia , Tálamo/cirurgia , Idoso , Imagem de Tensor de Difusão , Feminino , Ablação por Ultrassom Focalizado de Alta Intensidade , Humanos , Estudos Longitudinais , Masculino , Tálamo/diagnóstico por imagem
18.
World Neurosurg ; 126: e1169-e1182, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30885860

RESUMO

OBJECTIVE: Thalamic glioma is a type of midline glioma with poor outcomes. In the present study, we investigated the clinical and molecular features of thalamic gliomas in Chinese patients. METHODS: The data from 26 patients with thalamic glioma who had undergone surgery at Shanghai Huashan Hospital from January 2011 to August 2015 were retrospectively analyzed. Various clinical and molecular factors were evaluated to explore their effects on prognosis. H3K27M mutation status and its association with relevant molecular factors were also investigated. RESULTS: The mean age of the patients was 38.88 years, and no significant difference was found in sex. The most common initial symptoms were headaches (38.46%; 10 of 26) and motor deficits (30.77%; 8 of 26). The H3K27M mutation was identified in 12 patients, and mutant thalamic glioma showed less frequent O-6-methylguanine DNA methyltransferase (MGMT) promoter methylation compared with the wild-type group (P = 0.015; χ1 test). Multivariate analysis showed that the H3K27M mutation was an independent unfavorable prognostic factor for overall survival. MGMT promoter unmethylation and the TP53 mutation were identified as negative prognostic factors for progression-free survival. CONCLUSIONS: Our results revealed the clinical and molecular characteristics of thalamic glioma in China. Our data have shown the absence of MGMT promoter methylation in H3K27M mutant thalamic glioma, validating it as a hallmark of H3K27M mutant gliomas. In addition, H3K27M mutation was identified as the sole unfavorable prognostic factor on overall survival. MGMT promoter unmethylation and TP53 mutation were identified as independent prognostic factors for progression-free survival.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioma/genética , Glioma/patologia , Tálamo/patologia , Adolescente , Adulto , Idoso , Criança , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
19.
Ann Neurol ; 85(3): 340-351, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30719730

RESUMO

OBJECTIVE: Central nervous system pathology in multiple sclerosis includes both focal inflammatory perivascular injury and injury to superficial structures, including the subpial region of the cortex, which reportedly exhibits a gradient of damage from the surface inward. We assessed how early in the multiple sclerosis course a "surface-in" process of injury suggesting progressive biology may begin. METHODS: We focused on the thalamus, which notably has both a cerebrospinal fluid (CSF) interface and a white matter interface. Thalamic volume trajectories were assessed in a prospectively followed cohort of children from initial presentation with either multiple sclerosis or monophasic acquired demyelination, and healthy controls. Voxelwise volume changes were calculated using deformation-based morphometry, and analyzed in relation to distance from the CSF interface by mixed effects modeling and semiparametric smoothing methods. RESULTS: Twenty-seven children with multiple sclerosis and 73 children with monophasic demyelination were prospectively followed with yearly brain scans (mean follow-up = 4.6 years, standard deviation = 1.9). A total of 282 healthy children with serial scans were included as controls. Relative to healthy controls, children with multiple sclerosis and children with monophasic demyelination demonstrated volume loss in thalamic regions adjacent to the white matter. However, only children with multiple sclerosis exhibited an additional surface-in gradient of thalamic injury on the ventricular side, which was already notable in the first year of clinical disease (asymptote estimate = 3.01, 95% confidence interval [CI] = 1.44-4.58, p = 0.0002) and worsened over time (asymptote:time estimate = 0.33, 95% CI = 0.12-0.54, p = 0.0021). INTERPRETATION: Our results suggest that a multiple sclerosis disease-specific surface-in process of damage can manifest at the earliest stages of the disease. ANN NEUROL 2019;85:340-351.


Assuntos
Esclerose Múltipla/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/diagnóstico por imagem , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/patologia , Progressão da Doença , Seguimentos , Humanos , Imagem por Ressonância Magnética , Esclerose Múltipla/patologia , Tamanho do Órgão , Tálamo/patologia
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