TY  - JOUR
A1  - Kuzkina, A.
A1  - Rößle, J.
A1  - Seger, A.
A1  - Panzer, C.
A1  - Kohl, A.
A1  - Maltese, V.
A1  - Musacchio, T.
A1  - Blaschke, S. J.
A1  - Tamgüney, G.
A1  - Kaulitz, S.
A1  - Rak, K.
A1  - Scherzad, A.
A1  - Zimmermann, P. H.
A1  - Klussmann, J. P.
A1  - Hackenberg, S.
A1  - Volkmann, J.
A1  - Sommer, C.
A1  - Sommerauer, M.
A1  - Doppler, K.
T1  - Combining skin and olfactory α-synuclein seed amplification assays (SAA)—towards biomarker-driven phenotyping in synucleinopathies
JF  - npj Parkinson’s Disease
N2  - Seed amplification assays (SAA) are becoming commonly used in synucleinopathies to detect α-synuclein aggregates. Studies in Parkinson’s disease (PD) and isolated REM-sleep behavior disorder (iRBD) have shown a considerably lower sensitivity in the olfactory epithelium than in CSF or skin. To get an insight into α-synuclein (α-syn) distribution within the nervous system and reasons for low sensitivity, we compared SAA assessment of nasal brushings and skin biopsies in PD (n = 27) and iRBD patients (n = 18) and unaffected controls (n = 30). α-syn misfolding was overall found less commonly in the olfactory epithelium than in the skin, which could be partially explained by the nasal brushing matrix exerting an inhibitory effect on aggregation. Importantly, the α-syn distribution was not uniform: there was a higher deposition of misfolded α-syn across all sampled tissues in the iRBD cohort compared to PD (supporting the notion of RBD as a marker of a more malignant subtype of synucleinopathy) and in a subgroup of PD patients, misfolded α-syn was detectable only in the olfactory epithelium, suggestive of the recently proposed brain-first PD subtype. Assaying α-syn of diverse origins, such as olfactory (part of the central nervous system) and skin (peripheral nervous system), could increase diagnostic accuracy and allow better stratification of patients.
KW  - diagnostic markers
KW  - Parkinson's disease
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357687
SN  - 2373-8057
VL  - 9
ER  - 
TY  - JOUR
A1  - Mencacci, Niccoló E.
A1  - Isaias, Ioannis U.
A1  - Reich, Martin M.
A1  - Ganos, Christos
A1  - Plagnol, Vincent
A1  - Polke, James M.
A1  - Bras, Jose
A1  - Hersheson, Joshua
A1  - Stamelou, Maria
A1  - Pittman, Alan M.
A1  - Noyce, Alastair J.
A1  - Mok, Kin Y.
A1  - Opladen, Thomas
A1  - Kunstmann, Erdmute
A1  - Hodecker, Sybille
A1  - Münchau, Alexander
A1  - Volkmann, Jens
A1  - Samnick, Samuel
A1  - Sidle, Katie
A1  - Nanji, Tina
A1  - Sweeney, Mary G.
A1  - Houlden, Henry
A1  - Batla, Amit
A1  - Zecchinelli, Anna L.
A1  - Pezzoli, Gianni
A1  - Marotta, Giorgio
A1  - Lees, Andrew
A1  - Alegria, Paulo
A1  - Krack, Paul
A1  - Cormier-Dequaire, Florence
A1  - Lesage, Suzanne
A1  - Brice, Alexis
A1  - Heutink, Peter
A1  - Gasser, Thomas
A1  - Lubbe, Steven J.
A1  - Morris, Huw R.
A1  - Taba, Pille
A1  - Koks, Sulev
A1  - Majounie, Elisa
A1  - Gibbs, J. Raphael
A1  - Singleton, Andrew
A1  - Hardy, John
A1  - Klebe, Stephan
A1  - Bhatia, Kailash P.
A1  - Wood, Nicholas W.
T1  - Parkinson’s disease in GTP cyclohydrolase 1 mutation carriers
JF  - Brain
N2  - GTP cyclohydrolase 1, encoded by the GCH1 gene, is an essential enzyme for dopamine production in nigrostriatal cells. Loss-of-function mutations in GCH1 result in severe reduction of dopamine synthesis in nigrostriatal cells and are the most common cause of DOPA-responsive dystonia, a rare disease that classically presents in childhood with generalized dystonia and a dramatic long-lasting response to levodopa. We describe clinical, genetic and nigrostriatal dopaminergic imaging ([(123)I]N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl) tropane single photon computed tomography) findings of four unrelated pedigrees with DOPA-responsive dystonia in which pathogenic GCH1 variants were identified in family members with adult-onset parkinsonism. Dopamine transporter imaging was abnormal in all parkinsonian patients, indicating Parkinson's disease-like nigrostriatal dopaminergic denervation. We subsequently explored the possibility that pathogenic GCH1 variants could contribute to the risk of developing Parkinson's disease, even in the absence of a family history for DOPA-responsive dystonia. The frequency of GCH1 variants was evaluated in whole-exome sequencing data of 1318 cases with Parkinson's disease and 5935 control subjects. Combining cases and controls, we identified a total of 11 different heterozygous GCH1 variants, all at low frequency. This list includes four pathogenic variants previously associated with DOPA-responsive dystonia (Q110X, V204I, K224R and M230I) and seven of undetermined clinical relevance (Q110E, T112A, A120S, D134G, I154V, R198Q and G217V). The frequency of GCH1 variants was significantly higher (Fisher's exact test P-value 0.0001) in cases (10/1318 = 0.75%) than in controls (6/5935 = 0.1%; odds ratio 7.5; 95% confidence interval 2.4-25.3). Our results show that rare GCH1 variants are associated with an increased risk for Parkinson's disease. These findings expand the clinical and biological relevance of GTP cycloydrolase 1 deficiency, suggesting that it not only leads to biochemical striatal dopamine depletion and DOPA-responsive dystonia, but also predisposes to nigrostriatal cell loss. Further insight into GCH1-associated pathogenetic mechanisms will shed light on the role of dopamine metabolism in nigral degeneration and Parkinson's disease.
KW  - DOPA-responsive-dystonia
KW  - GCH1
KW  - Parkinson's disease
KW  - dopamine
KW  - exome sequencing
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-121268
VL  - 137
IS  - 9
ER  - 
TY  - JOUR
A1  - Deeb, Wissam
A1  - Giordano, James J.
A1  - Rossi, Peter J.
A1  - Mogilner, Alon Y.
A1  - Gunduz, Aysegul
A1  - Judy, Jack W.
A1  - Klassen, Bryan T.
A1  - Butson, Christopher R.
A1  - Van Horne, Craig
A1  - Deny, Damiaan
A1  - Dougherty, Darin D.
A1  - Rowell, David
A1  - Gerhardt, Greg A.
A1  - Smith, Gwenn S.
A1  - Ponce, Francisco A.
A1  - Walker, Harrison C.
A1  - Bronte-Stewart, Helen M.
A1  - Mayberg, Helen S.
A1  - Chizeck, Howard J.
A1  - Langevin, Jean-Philippe
A1  - Volkmann, Jens
A1  - Ostrem, Jill L.
A1  - Shute, Jonathan B.
A1  - Jimenez-Shahed, Joohi
A1  - Foote, Kelly D.
A1  - Wagle Shukla, Aparna
A1  - Rossi, Marvin A.
A1  - Oh, Michael
A1  - Pourfar, Michael
A1  - Rosenberg, Paul B.
A1  - Silburn, Peter A.
A1  - de Hemptine, Coralie
A1  - Starr, Philip A.
A1  - Denison, Timothy
A1  - Akbar, Umer
A1  - Grill, Warren M.
A1  - Okun, Michael S.
T1  - Proceedings of the Fourth Annual Deep Brain Stimulation Think Tank: A Review of Emerging Issues and Technologies
JF  - Frontiers in Integrative Neuroscience
N2  - This paper provides an overview of current progress in the technological advances and the use of deep brain stimulation (DBS) to treat neurological and neuropsychiatric disorders, as presented by participants of the Fourth Annual DBS Think Tank, which was convened in March 2016 in conjunction with the Center for Movement Disorders and Neurorestoration at the University of Florida, Gainesveille FL, USA. The Think Tank discussions first focused on policy and advocacy in DBS research and clinical practice, formation of registries, and issues involving the use of DBS in the treatment of Tourette Syndrome. Next, advances in the use of neuroimaging and electrochemical markers to enhance DBS specificity were addressed. Updates on ongoing use and developments of DBS for the treatment of Parkinson's disease, essential tremor, Alzheimer's disease, depression, post-traumatic stress disorder, obesity, addiction were presented, and progress toward innovation(s) in closed-loop applications were discussed. Each section of these proceedings provides updates and highlights of new information as presented at this year's international Think Tank, with a view toward current and near future advancement of the field.
KW  - deep brain stimulation
KW  - Parkinson’s disease
KW  - Alzheimer’s disease
KW  - closed-loop
KW  - depression
KW  - post-traumatic stress disorder
KW  - Tourette syndrome
KW  - DARPA
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-168493
VL  - 10
IS  - 38
ER  - 
TY  - JOUR
A1  - Contarino, Maria Fiorella
A1  - Smit, Marenka
A1  - van den Dool, Joost
A1  - Volkmann, Jens
A1  - Tijssen, Marina A. J.
T1  - Unmet Needs in the Management of Cervical Dystonia
JF  - Frontiers in Neurology
N2  - Cervical dystonia (CD) is a movement disorder which affects daily living of many patients. In clinical practice, several unmet treatment needs remain open. This article focuses on the four main aspects of treatment. We describe existing and emerging treatment approaches for CD, including botulinum toxin injections, surgical therapy, management of non-motor symptoms, and rehabilitation strategies. The unsolved issues regarding each of these treatments are identified and discussed, and possible future approaches and research lines are proposed.
KW  - cervical dystonia
KW  - botulinum toxin
KW  - deep brain stimulation
KW  - physical therapy modalities
KW  - non-motor features
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165225
VL  - 7
IS  - 165
ER  - 
TY  - JOUR
A1  - Kremer, Naomi I.
A1  - Pauwels, Rik W. J.
A1  - Pozzi, Nicolò G.
A1  - Lange, Florian
A1  - Roothans, Jonas
A1  - Volkmann, Jens
A1  - Reich, Martin M.
T1  - Deep Brain Stimulation for Tremor: Update on Long-Term Outcomes, Target Considerations and Future Directions
JF  - Journal of Clinical Medicine
N2  - Deep brain stimulation (DBS) of the thalamic ventral intermediate nucleus is one of the main advanced neurosurgical treatments for drug-resistant tremor. However, not every patient may be eligible for this procedure. Nowadays, various other functional neurosurgical procedures are available. In particular cases, radiofrequency thalamotomy, focused ultrasound and radiosurgery are proven alternatives to DBS. Besides, other DBS targets, such as the posterior subthalamic area (PSA) or the dentato-rubro-thalamic tract (DRT), may be appraised as well. In this review, the clinical characteristics and pathophysiology of tremor syndromes, as well as long-term outcomes of DBS in different targets, will be summarized. The effectiveness and safety of lesioning procedures will be discussed, and an evidence-based clinical treatment approach for patients with drug-resistant tremor will be presented. Lastly, the future directions in the treatment of severe tremor syndromes will be elaborated.
KW  - deep brain stimulation
KW  - tremor
KW  - essential tremor
KW  - Parkinson’s disease
KW  - outcomes
KW  - clinical approach
KW  - target considerations
KW  - future directions
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244982
SN  - 2077-0383
VL  - 10
IS  - 16
ER  -