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Neurogenetics 2022 Apr 9. Epub 2022 Apr 9.

Movement Disorders Centre, Toronto Western Hospital, University of Toronto, Toronto, ON, Canada.

The syndromic group of hereditary spastic paraplegias has a heterogeneous clinical profile and a broad differential diagnosis, including neurometabolic disorders that are potentially treatable. This group includes 5,10-methylenetetrahydrofolate reductase deficiency, cobalamin C deficiency disease, dopamine responsive dystonia, cerebrotendinous xanthomatosis, biotinidase deficiency, GLUT1 deficiency syndrome, delta-e-pyrroline-carboxylase-synthetase deficiency, hyperonithinemia-hyperammonemia-homocitrullinuria syndrome, arginase deficiency, multiple carboxylase deficiency, and X-linked adrenoleukodystrophy. This review describes these diseases in detail, highlighting the importance of early diagnosis and effective treatment aiming at preserving functionality and quality of life in these patients. Read More

World J Clin Cases 2021 Oct;9(28):8552-8556

School of Basic Medical Sciences, Beijing University of Chinese Medicine, Beijing 100029, China.

Background: Spinocerebellar ataxia type 3 (SCA3) is a rare neurodegenerative disease with high genetic heterogeneity. SCA3 mainly manifests as progressive cerebellar ataxia accompanied by paralysis of extraocular muscles, dysphagia, lingual fibrillation, pyramidal tract sign, and extrapyramidal system sign. However, it rarely has clinical manifestations similar to Parkinson-like symptoms, and is even rarer in patients sensitive to dopamine. Read More

Tremor Other Hyperkinet Mov (N Y) 2021 06 24;11:23. Epub 2021 Jun 24.

Department of neurology, Beaumont Hospital, Dublin.

Background: Mutations in the GCH-1 gene are associated with Autosomal Dominant Dopamine Responsive Dystonia (DYT 5). One of the hallmarks of this condition is dramatic and sustained response to low doses of levodopa.

Case Report: We present the case of a 22 year old female patient with genetically confirmed GCH-1 Dopa-Responsive Dystonia who had no response to low dose Levodopa but who achieved symptom control on a total dose of 900 mg/day. Read More

Saudi J Anaesth 2020 Oct-Dec;14(4):524-527. Epub 2020 Sep 24.

Department of Anaesthesia, Dr. Sampurnanand Medical College (Mahatma Gandhi Hospital), Jodhpur, Rajasthan, India.

Segawa's syndrome, dopamine-responsive dystonia, is a rare genetic disorder that typically begins in childhood by around 4-6 years of age. It is characterized by abnormal gait and dystonia. A 33-year-old man presented for autologous skin grafting of a nonhealing wound under general anesthesia. Read More

Brain 2021 03;144(2):462-472

Department of Human Genetics, McGill University, Montréal, QC, H3A 1A1, Canada.

Genome-wide association studies (GWAS) have identified numerous loci associated with Parkinson's disease. The specific genes and variants that drive the associations within the vast majority of these loci are unknown. We aimed to perform a comprehensive analysis of selected genes to determine the potential role of rare and common genetic variants within these loci. Read More

Curr Opin Neurol 2020 08;33(4):474-481

Center of Expertise for Parkinson & Movement Disorders, Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands.

Purpose Of Review: We discuss the latest neuroimaging studies investigating the pathophysiology of Parkinson's tremor, essential tremor, dystonic tremor and Holmes tremor.

Recent Findings: Parkinson's tremor is associated with increased activity in the cerebello-thalamo-cortical circuit, with interindividual differences depending on the clinical dopamine response of the tremor. Although dopamine-resistant Parkinson's tremor arises from a larger contribution of the (dopamine-insensitive) cerebellum, dopamine-responsive tremor may be explained by thalamic dopamine depletion. Read More

Front Neurol 2019 29;10:555. Epub 2019 May 29.

Honorary Senior Lecturer in Paediatric Neurology, Imperial College, London, United Kingdom.

Mutations in the gene have been implicated in the pathogenesis of early-onset Parkinson's disease. We present a case of movement disorder in a 4-year-old child from consanguineous parents and with a family history of Dopamine responsive dystonia, who was diagnosed with early-onset Parkinson's disease based on initial identification of a pathogenic mutation. However, the evolution of the child's clinical picture was unusually rapid, with a preponderance of pyramidal rather than extrapyramidal symptoms, leading to re-investigation of the case with further imaging and genetic sequencing. Read More

Parkinsonism Relat Disord 2019 08 3;65:277-278. Epub 2019 Jun 3.

Department of Neurology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan; Research Institute for Diseases of Old Age, Graduate School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.

Front Syst Neurosci 2018 27;12:28. Epub 2018 Jun 27.

Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States.

Striatal cholinergic dysfunction is a common phenotype associated with various forms of dystonia in which anti-cholinergic drugs have some therapeutic benefits. However, the underlying substrate of striatal cholinergic defects in dystonia remain poorly understood. In this study, we used a recently developed knock-in mouse model of dopamine-responsive dystonia (DRD) with strong symptomatic responses to anti-cholinergic drugs, to assess changes in the prevalence and morphology of striatal cholinergic interneurons (ChIs) in a model of generalized dystonia. Read More

Pract Neurol 2015 Oct 4;15(5):340-5. Epub 2015 Jun 4.

Department of Neurology, Institute of Neurological Sciences, Southern General Hospital, Glasgow, UK.

The clinical spectrum of dopamine-responsive dystonias (DRDs) has expanded over the last decade to comprise several distinct disorders. At the milder end of the clinical spectrum is the autosomal-dominant guanosine triphosphate cyclohydrolase deficiency syndrome (GTPCH-DRD), and at the more severe end is the much less common autosomal recessive tyrosine hydroxylase deficiency syndrome (TH-DRD), with intermediate forms in between. Understanding the pathophysiology of DRDs can help in their optimal diagnosis and management. Read More

JIMD Rep 2015 26;24:109-13. Epub 2015 May 26.

Division of Neuropediatrics and Metabolic Medicine, Department of General Pediatrics, University Hospital Heidelberg, Im Neuenheimer Feld 430, 69120, Heidelberg, Germany.

Sepiapterin reductase (SR) deficiency is a rare autosomal recessively inherited error of tetrahydrobiopterin (BH4) biosynthesis, resulting in disturbed dopaminergic and serotonergic neurotransmission. The clinical phenotype is characterized by dopa-responsive movement disorders including muscular hypotonia, dystonia, and parkinsonism. Due to the rarity of the disease, the phenotype of SR deficiency is far from being completely understood. Read More

Mol Biosyst 2014 Dec 11;10(12):3101-10. Epub 2014 Sep 11.

Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.

L-Dopa has been used to increase dopamine concentrations in the treatment of Parkinson's disease and dopamine-responsive dystonia. The binding interaction between L-dopa (phytochemical) and human serum albumin (HSA) under simulated physiological conditions was investigated by spectroscopic and molecular modeling methods. The results revealed that L-dopa caused fluorescence emission quenching of HSA through a static quenching procedure and the binding constant obtained was 2. Read More

Mov Disord Clin Pract 2014 Sep 6;1(3):154-160. Epub 2014 Jun 6.

Movement Disorders Section, Neuroscience Department Raul Carrea Institute for Neurological Research (FLENI) Buenos Aires Argentina.

Autosomal dominant cerebellar ataxias (ADCAs) are clinically heterogeneous disorders classified according to genetic subtype and collectively known as SCAs. In a few SCAs, movement disorders can be the most frequent extracerebellar sign. The aim of this article is to perform a systematic review of movement disorders frequency and characteristics in ADCAs. Read More

Can J Neurol Sci 2003 Mar;30 Suppl 1:S34-44

Unité des Troubles du Mouvement André-Barbeau, Centre Hospitalier de l'Université de Montréal, Montreal, QC, Canada.

Dystonia is a syndrome of sustained muscular contractions with numerous underlying etiologies. This review examines the varied phenomenology of dystonias, its evolving classification including recent genetic data as well as its clinical investigation and treatment. Although age of onset, anatomical distribution and family history are key elements of the investigation of dystonia, classification increasingly relies on etiologic and genetic criteria. Read More