RESUMO
UNLABELLED: Parkinson disease with and without dementia (PDD and PD, respectively), dementia with Lewy bodies (DLB), and Alzheimer dementia (AD) traditionally have been viewed as distinct clinical and pathologic entities. However, intriguing overlaps in biochemical, clinical, and imaging findings question the concept of distinct entities and suggest a continuous spectrum in which individual patients express PD-typical patterns and AD-typical patterns to a variable degree. METHODS: Following this concept, we built a topological map based on regional patterns of the cerebral metabolic rate of glucose as measured with (18)F-FDG PET to rank and localize single subjects' disease status according to PD-typical (PD vs. controls) and AD-typical (AD vs. controls) pattern expression in patients clinically characterized as PD, PDD, DLB, amnestic mild cognitive impairment, and AD. RESULTS: The topology generally confirmed an indivisible spectrum of disease manifestation according to 2 separable expression patterns. The expression values derived from the first pattern were highly correlated with individual cognitive, but not motor, disability. The opposite was found for the corresponding expression values of the second pattern. CONCLUSION: The metabolic imaging analysis supports the notion that there is a continuous spectrum of neurodegeneration between AD and PD. Furthermore, PDD and DLB may in fact represent 1 overlapping disease entity, characterized by the presence of mixed neuropathology and only different by the time course.
Assuntos
Cognição , Transtornos dos Movimentos/metabolismo , Transtornos dos Movimentos/psicologia , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/psicologia , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/psicologia , Mapeamento Encefálico , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/psicologia , Feminino , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador , Doença por Corpos de Lewy/diagnóstico por imagem , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/psicologia , Masculino , Transtornos dos Movimentos/diagnóstico por imagem , Doenças Neurodegenerativas/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Doença de Parkinson/psicologia , Doença de Parkinson Pós-Encefalítica/diagnóstico por imagem , Doença de Parkinson Pós-Encefalítica/metabolismo , Doença de Parkinson Pós-Encefalítica/psicologia , Cintilografia , Compostos RadiofarmacêuticosRESUMO
Postencephalitic parkinsonism (PEP), a chronic complication of encephalitis lethargica, is a tauopathy characterized by multisystem neuronal loss and gliosis with widespread neurofibrillary lesions composed of both 3- and 4-repeat (3R and 4R) tau isoforms. Previous immunohistochemical studies in a small number of PEP cases demonstrated absence of Lewy bodies as well as the lack of other alpha-synuclein pathology, classifying PEP as a "pure" tauopathy. Neuropathologic examination of 10 brains with clinico-pathologically verified PEP confirmed widespread neurodegeneration in subcortical and brainstem areas associated with multifocal neurofibrillary pathology comprising both 3R and 4R tau. Very rare beta-amyloid deposits were observed in two elderly patients, while Lewy bodies and neurites or any other alpha-synuclein deposits were completely absent. The causes and molecular background of total absence of alpha-synuclein pathology in PEP, in contrast to most other tauopathies, remain as unknown as the pathogenesis of PEP.
Assuntos
Doença de Parkinson Pós-Encefalítica/patologia , alfa-Sinucleína/metabolismo , Adulto , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Tronco Encefálico/metabolismo , Tronco Encefálico/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Degeneração Neural , Neurônios/metabolismo , Doença de Parkinson Pós-Encefalítica/metabolismo , Tauopatias/metabolismo , Tauopatias/patologiaRESUMO
Tau-immunoreactive astrocytes have been reported in the brain of progressive supranuclear palsy (PSP) and are referred to as glial fibrillary tangles (GFTs). We found a number of GFTs in the heavily degenerated brain region in four cases of postencephalitic parkinsonism of Economo (PPE) with a clinical history of over a half-century. GFTs had the appearance of tufts of spider-like radiating fibers or small thorn-like feature by Gallyas-Braak method and also by anti-tau immunostaining.
Assuntos
Encéfalo/patologia , Emaranhados Neurofibrilares/metabolismo , Neuroglia/metabolismo , Doença de Parkinson Pós-Encefalítica/metabolismo , Proteínas tau/metabolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/imunologia , Neuroglia/imunologia , Doença de Parkinson Pós-Encefalítica/imunologia , Doença de Parkinson Pós-Encefalítica/patologia , Proteínas tau/imunologiaRESUMO
The distribution of methionine-enkephalin (ME)-like and substance P (SP)-like immunoreactivity in the basal ganglia of untreated schizophrenics as compared with normal control cases, and untreated Huntington and Parkinson patients was studied using the unlabeled peroxidase-antiperoxidase (PAP) method. ME but not SP was reduced in the pallidum of one of six schizophrenics. The remaining five cases showed no differences to the controls. In contrast, no or only very faint homogeneously distributed ME and SP was found in any part of the basal ganglia in Huntington's disease. In Parkinson's disease, SP immunoreactivity was within normal range.
