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1.
AJNR Am J Neuroradiol ; 43(10): 1516-1522, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36137664

RESUMO

BACKGROUND AND PURPOSE: Sturge-Weber syndrome is a rare congenital neuro-oculo-cutaneous disorder. Although the principal mechanism of Sturge-Weber syndrome is characterized by a leptomeningeal vascular malformation, few data regarding perfusion abnormalities of the brain parenchyma are available. Therefore, the aim of this study was to assess the diagnostic performance of arterial spin-labeling perfusion imaging in the early stage of Sturge-Weber syndrome before 1 year of age until 3.5 years of age. We hypothesized that a leptomeningeal vascular malformation has very early hypoperfusion compared with controls with healthy brains. MATERIALS AND METHODS: We compared the CBF using arterial spin-labeling perfusion imaging performed at 3T MR imaging in the brain parenchymal regions juxtaposing the leptomeningeal vascular malformation in patients with Sturge-Weber syndrome (n = 16; 3.5 years of age or younger) with the corresponding areas in age-matched controls with healthy brains (n = 58). The analysis was performed following two complementary methods: a whole-brain voxel-based analysis and a visual ROI analysis focused on brain territory of the leptomeningeal vascular malformation. RESULTS: Whole-brain voxel-based comparison revealed a significant unilateral decrease in CBF localized in the affected cortices of patients with Sturge-Weber syndrome (P < .001). CBF values within the ROIs in patients with Sturge-Weber syndrome were lower than those in controls (in the whole cohort: median, 25 mL/100g/min, versus 44 mL/100g/min; P < .001). This finding was also observed in the group younger than 1 year of age, emphasizing the high sensitivity of arterial spin-labeling in this age window in which the diagnosis is difficult. CONCLUSIONS: Arterial spin-labeling perfusion imaging in the early stage of Sturge-Weber syndrome can help to diagnose the disease by depicting a cortical hypoperfusion juxtaposing the leptomeningeal vascular malformation.


Assuntos
Síndrome de Sturge-Weber , Malformações Vasculares , Humanos , Pré-Escolar , Síndrome de Sturge-Weber/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Perfusão , Imagem de Perfusão
2.
Sci Rep ; 10(1): 6379, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286406

RESUMO

Humans show great interindividual variability in the degree they engage in social relationship. The neural basis of this variability is still poorly understood, particularly in children. In this study, we aimed to investigate the neural basis of interindividual variability in the first step of social behavior, that is social perception, in typically developing children. For that purpose, we first used eye-tracking to objectively measure eye-gaze processing during passive visualization of social movie clips in 24 children and adolescents (10.5 ± 2.9 y). Secondly, we correlated eye-tracking data with measures of fractional anisotropy, an index of white matter microstructure, obtained using diffusion tensor imaging MRI. The results showed a large interindividual variability in the number of fixations to the eyes of characters during visualization of social scenes. In addition, whole-brain analysis showed a significant positive correlation between FA and number of fixations to the eyes,mainly in the temporal part of the superior longitudinal fasciculi bilaterally, adjacent to the posterior superior temporal cortex. Our results indicate the existence of a neural signature associated with the interindividual variability in social perception in children, contributing for better understanding the neural basis of typical and atypical development of a broader social expertise.


Assuntos
Córtex Cerebral/fisiologia , Rede Nervosa/fisiologia , Percepção Social , Substância Branca/fisiologia , Adolescente , Criança , Imagem de Tensor de Difusão , Feminino , Fixação Ocular , Humanos , Masculino
3.
J Nutr Health Aging ; 22(3): 425-430, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29484357

RESUMO

OBJECTIVES: Since physical activity (PA) has demonstrated benefits for cardiovascular health, it is possible to hypothesize that higher or increasing PA slows the progression of white matter hyperintensities (WMH). We investigated the association between PA and the progression of WMH in non-demented older adults with memory complaints. DESIGN: We included 152 participants (mean age 74.7±3.8 years; 63.8% women) in the analyses, in whom information on self-reported PA and MRI was available at both baseline and 3-year follow-up. From the PA questionnaire, the baseline metabolic equivalent of task (MET-minute/week) and changes in MET-minute/week over three years were separately calculated for overall, leisure-time, and non-leisure time PA. WMH volume at baseline and 3-year follow-up was obtained by using an automated segmentation algorithm. RESULTS: Mixed-effect linear regression models showed that none of the baseline PA variables was associated with progression of WMH over time. People who had decreased their PA levels over three years tended to show greater progression of WMH compared with those who had maintained PA levels of ≥1200 MET-min/week (roughly equivalent to ≥300 minutes of brisk walking) in the unadjusted model (ß±SE=4.85±2.42, p=0.045); however, this association was no longer significant after adjustment for confounders (ß±SE =3.63±2.18, p=0.096). CONCLUSIONS: We did not find any significant association between PA and WMH in non-demented older adults with memory complaints. However, decrease over time in PA levels tended to be associated with progression of WMH. A larger longitudinal study with data on PA assessed using objective measures would provide important information in this field.


Assuntos
Atividades Cotidianas , Cognição/fisiologia , Exercício Físico , Transtornos da Memória/fisiopatologia , Caminhada , Substância Branca/fisiologia , Idoso , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino
4.
J Nutr Health Aging ; 22(1): 174-179, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29300438

RESUMO

OBJECTIVES: The association between circulating biomarkers of red blood cells (RBC) omega-3 polyunsaturated fatty acids (PUFAs) and cerebral white matter hyperintensities (WMH) on the brain MRI remains yet unclear. We investigated the cross-sectional and prospective associations of RBC omega-3 PUFAs with WMH in dementia-free older adults with subjective memory complaints. DESIGN: Participants were 234 older adults with assessments for both PUFA and MRI near to baseline; among them, 79 also had an MRI assessment at 3-year follow-up. The measurement of WMH volume was obtained by an automated segmentation algorithm. We related individual or combinational baseline RBC omega-3 PUFAs levels with baseline WMH volumes and WMH evolution over 3 years. We carried out multiple (cross-sectional) and mixed-effect (prospective analysis, with random effects at participant's level) linear regressions with adjustment for age, sex, time interval between date of blood draw for measurement of fatty acids and date of brain MRI, the status of APOE e4 carrier, body mass index, and vascular risk factors. Associations were considered significant at p ≤ 0.006 to take into account multiplicity (8 comparisons). RESULTS: None of the eight RBC omega-3 PUFAs tested was significantly associated with WMH at both cross-sectional and prospective analyses. CONCLUSIONS: We did not find any association between omega-3 PUFAs and WMH in non-demented older adults with memory complaints. A longer longitudinal study with data on omega-3 PUFAs and WMH would contribute important information to this field.


Assuntos
Eritrócitos/metabolismo , Ácidos Graxos Ômega-3/uso terapêutico , Substância Branca/irrigação sanguínea , Idoso , Estudos Transversais , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/farmacologia , Feminino , Humanos , Estudos Longitudinais , Masculino
5.
Ann Pathol ; 16(4): 307-9, 1996 Sep.
Artigo em Francês | MEDLINE | ID: mdl-9172626

RESUMO

This technical note describes antigen retrieval procedures using a pressure cooker. These procedures are perfectly adapted to routine immunohistochemistry and improve the overall quality of immunostaining.


Assuntos
Antígenos/análise , Temperatura Alta , Imuno-Histoquímica/métodos , Automação , Pressão , Soluções
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