DuodenoscopyCrohn DiseaseParkinson DiseaseAlzheimer DiseaseAmyloid beta-Peptidesalpha-SynucleinAntiparkinson Agentstau ProteinsBrainAmyloid beta-Protein PrecursorParkinsonian DisordersNeurofibrillary TanglesPlaque, AmyloidLewy BodiesDementiaParkinson Disease, SecondaryLewy Body DiseaseLevodopaGlucosylceramidaseCognition DisordersAmyloidNeuropsychological TestsApolipoprotein E4Substantia NigraNeurodegenerative DiseasesNeurofibrilsNeuronsDeep Brain StimulationAmyloid Precursor Protein SecretasesPresenilin-1Multiple System AtrophyAge of OnsetDopamineNerve Degeneration1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridineMild Cognitive ImpairmentAtrophyDopaminergic NeuronsOxidopamineDementia, VascularSupranuclear Palsy, ProgressiveSubthalamic NucleusMental Status SchedulePeptide FragmentsGenetic Predisposition to DiseaseDisease Models, AnimalMPTP PoisoningGait Disorders, NeurologicCognitionApolipoproteins EMagnetic Resonance ImagingPostural BalancePositron-Emission TomographyPutamenAgingMutationHippocampusMice, TransgenicCase-Control StudiesDance TherapyPresenilin-2AutopsyHypokinesiaCerebral CortexSeverity of Illness IndexNerve Tissue ProteinsEssential TremorUbiquitin-Protein LigasesNeuroprotective AgentsDisease ProgressionBenzothiazolesMemory DisordersThiazolesAspartic Acid EndopeptidasesPedunculopontine Tegmental NucleusREM Sleep Behavior DisorderPostmortem ChangesOncogene ProteinsGenetic TestingGaucher DiseaseTyrosine 3-MonooxygenasePergolideGaitGenotypeCholinesterase InhibitorsLongitudinal StudiesCarbidopaMitochondriaMemantineBiological MarkersPresenilinsAniline CompoundsCohort Studiesbeta-SynucleinSynucleinsCorpus StriatumOxidative StressBrain ChemistryPC12 CellsNational Institute on Aging (U.S.)