RESUMO
Dendritic regression of striatal spiny projection neurons (SPNs) is a pathological hallmark of Parkinson's disease (PD). Here we investigate how chronic dopamine denervation and dopamine replacement with L-DOPA affect the morphology and physiology of direct pathway SPNs (dSPNS) in the rat striatum. We used a lentiviral vector optimized for retrograde labeling (FuG-B-GFP) to identify dSPNs in rats with 6-hydroxydopamine (6-OHDA) lesions. Changes in morphology and physiology of dSPNs were assessed through a combination of patch-clamp recordings and two photon microscopy. The 6-OHDA lesion caused a significant reduction in dSPN dendritic complexity. Following chronic L-DOPA treatment, dSPNs segregated into two equal-sized clusters. One group (here called "cluster-1"), showed sustained dendritic atrophy and a partially normalized electrophysiological phenotype. The other one ("cluster-2") exhibited dendritic regrowth and a strong reduction of intrinsic excitability. Interestingly, FosB/∆FosB induction by L-DOPA treatment occurred preferentially in cluster-2 dSPNs. Our study demonstrates the feasibility of retrograde FuG-B-GFP labeling to study dSPNs in the rat and reveals, for the first time, that a subgroup of dSPNs shows dendritic sprouting in response to chronic L-DOPA treatment. Investigating the mechanisms and significance of this response will greatly improve our understanding of the adaptations induced by dopamine replacement therapy in PD.
Assuntos
Neurônios/patologia , Doença de Parkinson/fisiopatologia , Degeneração Estriatonigral/fisiopatologia , Animais , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Dopamina/metabolismo , Discinesia Induzida por Medicamentos/metabolismo , Feminino , Levodopa/farmacologia , Camundongos , Camundongos Transgênicos , Neostriado/metabolismo , Fenótipo , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D1/metabolismoRESUMO
Objetivo: Avaliar os casos de aposentadoria por deficiência visual na região metropolitana do Recife de modo a facilitar estratégias para prevenir a invalidez. Métodos: Avaliação retrospectiva de 637 prontuários de pacientes aposentados no Posto de Atendimento ao Segurado do INSS de Afogados, no período de 2,5 anos. Resultados: 2,7 porcento dos casos de aposentadoria de origem oftalmológica, sendo 5,9 porcento devido a acidente de trabalho e 94,1 porcento por doença comum. As doenças oculares mais freqüentes foram: glaucoma, retinopatia diabética, retinopatia hipertensiva, luxação do cristalino por Síndrome de Marfan e queimadura química. Conclusão: O conhecimento das oftalmopatias que levaram à aposentadoria é importante no sentido de executar medidas de prevenção de cegueira e reabilitação visual.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Pessoas com Deficiência Visual , Estudos Retrospectivos , Avaliação da Capacidade de TrabalhoRESUMO
During a cholera epidemic, Vibrio cholerae was isolated from two springs which supplied mineral water to a spa and to a commercial water bottling plant. Epidemiologic investigation found that cholera attack rates were 10-fold greater among visitors to the spa than among non-visitors. A subsequent matched-pair case-control study which excluded persons who had visted the spa showed that a history of consumption of the bottled non-carbonated water was significantly more common among bacteriologically confirmed cholera cases than among paired controls.
