Assuntos
Movimentos Oculares/fisiologia , Manganês/sangue , Doença de Parkinson/fisiopatologia , ATPases Translocadoras de Prótons/genética , alfa-Sinucleína/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/sangue , Doença de Parkinson/genética , Adulto JovemRESUMO
KEY POINTS: A cerebellar dentate nuclei (DN) contribution to volitional oculomotor control has recently been hypothesized but not fully understood. Cerebrotendinous xanthomatosis (CTX) is a rare neurometabolic disease typically characterized by DN damage. In this study, we compared the ocular movement characteristics of two sets of CTX patients, with and without brain MRI evidence of DN involvement, with a set of healthy subjects. Our results suggest that DN participate in voluntary behaviour, such as the execution of antisaccades, and moreover are involved in controlling the precision of the ocular movement. The saccadic abnormalities related to DN involvement were independent of global and regional brain atrophy. Our study confirms the relevant role of DN in voluntary aspects of oculomotion and delineates specific saccadic abnormalities that could be used to detect the involvement of DN in other cerebellar disorders. ABSTRACT: It is well known that the medial cerebellum controls saccadic speed and accuracy. In contrast, the role of the lateral cerebellum (cerebellar hemispheres and dentate nuclei, DN) is less well understood. Cerebrotendinous xanthomatosis (CTX) is a lipid storage disorder due to mutations in CYP27A1, typically characterized by DN damage. CTX thus provides a unique opportunity to study DN in human oculomotor control. We analysed horizontal and vertical visually guided saccades and horizontal antisaccades of 19 CTX patients. Results were related to the presence/absence of DN involvement and compared with those of healthy subjects. To evaluate the contribution of other areas, abnormal saccadic parameters were compared with global and regional brain volumes. CTX patients executed normally accurate saccades with normal main sequence relationships, indicating that the brainstem and medial cerebellar structures were functionally spared. Patients with CTX executed more frequent multistep saccades and directional errors during the antisaccade task than controls. CTX patients with DN damage showed less precise saccades with longer latencies, and more frequent directional errors, usually not followed by corrections, than either controls or patients without DN involvement. These saccadic abnormalities related to DN involvement but were independent of global and regional brain atrophy. We hypothesize that two different cerebellar networks contribute to the metrics of a movement: the medial cerebellar structures determine accuracy, whereas the lateral cerebellar structures control precision. The lateral cerebellum (hemispheres and DN) also participates in modulating goal directed gaze behaviour, by prioritizing volitional over reflexive movements.
Assuntos
Núcleos Cerebelares/fisiologia , Movimentos Sacádicos , Xantomatose Cerebrotendinosa/fisiopatologia , Adolescente , Adulto , Estudos de Casos e Controles , Núcleos Cerebelares/diagnóstico por imagem , Núcleos Cerebelares/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeAssuntos
Fácies , Deformidades Congênitas do Pé , Hipotricose , Deficiência Intelectual , Adulto , Feminino , Deformidades Congênitas do Pé/complicações , Deformidades Congênitas do Pé/diagnóstico , Deformidades Congênitas do Pé/genética , Humanos , Hiperinsulinismo/etiologia , Hipotricose/complicações , Hipotricose/diagnóstico , Hipotricose/genética , Deficiência Intelectual/complicações , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Proteína KRIT1 , Proteínas Associadas aos Microtúbulos/genética , Mutação/genética , Fenótipo , Proteínas Proto-Oncogênicas/genética , Fatores de Transcrição/genéticaAssuntos
Paralisia de Bell , Gangliosidose GM1/imunologia , Herpes Simples/complicações , Idoso , Anticorpos/metabolismo , Paralisia de Bell/etiologia , Paralisia de Bell/metabolismo , Paralisia de Bell/virologia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Linhagem Celular Tumoral , Feminino , Herpes Simples/genética , Humanos , Imageamento por Ressonância Magnética , Simplexvirus/genética , Simplexvirus/patogenicidadeRESUMO
Neuromyotonia(NMT) or Isaacs syndrome is a rare syndrome characterized by continuous spontaneous muscle fiber contraction resulting from hyperexcitability of peripheral nerves often associated with autoimmune disorders and tumours. Here we report an unpublished association of NMT and bladder cancer.