Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 2 de 2
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34819378

RESUMO

We have studied the three-dimensional (3D) cytoarchitecture of the human hippocampus in neuropathologically healthy and Alzheimer's disease (AD) individuals, based on phase-contrast X-ray computed tomography of postmortem human tissue punch biopsies. In view of recent findings suggesting a nuclear origin of AD, we target in particular the nuclear structure of the dentate gyrus (DG) granule cells. Tissue samples of 20 individuals were scanned and evaluated using a highly automated approach of measurement and analysis, combining multiscale recordings, optimized phase retrieval, segmentation by machine learning, representation of structural properties in a feature space, and classification based on the theory of optimal transport. Accordingly, we find that the prototypical transformation between a structure representing healthy granule cells and the pathological state involves a decrease in the volume of granule cell nuclei, as well as an increase in the electron density and its spatial heterogeneity. The latter can be explained by a higher ratio of heterochromatin to euchromatin. Similarly, many other structural properties can be derived from the data, reflecting both the natural polydispersity of the hippocampal cytoarchitecture between different individuals in the physiological context and the structural effects associated with AD pathology.


Assuntos
Mapeamento Encefálico/métodos , Hipocampo/diagnóstico por imagem , Imageamento Tridimensional/métodos , Tomografia Computadorizada por Raios X/métodos , Núcleo Celular/metabolismo , Meios de Contraste , Giro Denteado/diagnóstico por imagem , Eucromatina/química , Substância Cinzenta/diagnóstico por imagem , Heterocromatina/química , Humanos , Aprendizado de Máquina , Distribuição Normal , Reconhecimento Automatizado de Padrão , Análise de Componente Principal , Reprodutibilidade dos Testes , Substância Branca/diagnóstico por imagem
2.
Clin Exp Rheumatol ; 31(6): 974-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23981294

RESUMO

OBJECTIVES: To compare clinical characteristics of children with chronic non-infectious osteomyelitis (CNO) with either mono- or multifocal bone lesions, and to report potential advantages of using whole-body MRI. METHODS: A retrospective evaluation of 31 children (19 girls, 12 boys) diagnosed with CNO between 2001 and 2011. CNO was diagnosed as mono-, or multifocal inflammatory bone lesions (osteomyelitis, osteitis, osteosclerosis), duration of complaints more than 6 weeks and exclusion of infection and malignancy. Clinical and radiological data were registered. The definition of mono- or multifocality was based on the description of imaging results. RESULTS: Mean age at disease onset was 10.3 ± 2.6 years. Mean duration of active disease was 44.4 ± 25.6 months. Twenty-two (71.0%) had two or more bone lesions and 9 (29.0%) had one lesion. Of those with multifocal lesions six were initially detected as monofocal. The most frequent location of the bone lesions was in the metaphysis of the lower extremities. MRI/CT discovered most lesions compared to x-ray and scintigraphy. MRI was performed in 93.5% of which 25.8 % had a whole-body-MRI. Whole-body MRI revealed disclosure of several silent lesions. Extra-osseous involvement occurred in 64.5%. In the multifocal group 22.7 % had psoriasis and 13.6 % had pustulosis palmoplantaris but neither was seen in the monofocal group. All were treated with NSAIDs; 54.8% corticosteroids, 29.1 % methotrexate, 9.7 % pamidronate and 3.2 % infliximab. CONCLUSIONS: Monofocal CNO had comparable clinical and radiological characteristics to multifocal disease. We conclude that whole-body MRI is a relevant screening instrument for the diagnosis of CNO.


Assuntos
Osteíte , Osteomielite , Adolescente , Corticosteroides/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Biópsia , Criança , Doença Crônica , Dinamarca/epidemiologia , Feminino , Humanos , Imunossupressores/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Osteíte/diagnóstico , Osteíte/tratamento farmacológico , Osteíte/epidemiologia , Osteomielite/diagnóstico , Osteomielite/tratamento farmacológico , Osteomielite/epidemiologia , Valor Preditivo dos Testes , Recidiva , Estudos Retrospectivos , Fatores de Tempo , Imagem Corporal Total
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...