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Zheng Z, Zhu Z, Pu J, Zhou C, Cao L, Lv D, Lu J, Zhao G, Chen Y, Tian J, Yin X, Zhang B, Yan Y, Zhao G. Early-onset familial essential tremor is associated with nucleotide expansions of spinocerebellar ataxia in China. Mol Biol Rep 2024; 51:113. [PMID: 38227102 DOI: 10.1007/s11033-023-09023-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Accepted: 10/23/2023] [Indexed: 01/17/2024]
Abstract
BACKGROUND Essential tremor (ET) is a neurological disease characterized by action tremor in upper arms. Although its high heritability and prevalence worldwide, its etiology and association with other diseases are still unknown. METHOD We investigated 10 common spinocerebellar ataxias (SCAs), including SCA1, SCA2, SCA3, SCA6, SCA7, SCA8, SCA12, SCA17, SCA36, dentatorubral-pallidoluysian atrophy (DRPLA) in 92 early-onset familial ET pedigrees in China collected from 2016 to 2022. RESULT We found one SCA12 proband carried 51 CAG repeats within PPP2R2B gene and one SCA3 proband with intermediate CAG repeats (55) with ATXN3 gene. The other 90 ET probands all had normal repeat expansions. CONCLUSION Tremor can be the initial phenotype of certain SCA. For early-onset, familial ET patients, careful physical examinations are needed before genetic SCA screening.
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Affiliation(s)
- Zhilin Zheng
- Department of Neurology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China
| | - Zeyu Zhu
- Department of Neurology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China
| | - Jiali Pu
- Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Chen Zhou
- Department of Neurology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China
| | - Lanxiao Cao
- Department of Neurology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China
| | - Dayao Lv
- Department of Neurology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China
| | - Jinyu Lu
- Department of Neurology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China
| | - Gaohua Zhao
- Department of Neurology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China
| | - Yanxing Chen
- Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jun Tian
- Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xinzhen Yin
- Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Baorong Zhang
- Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
| | - Yaping Yan
- Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
| | - Guohua Zhao
- Department of Neurology, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, Zhejiang, China.
- Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
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Mishima T, Yuasa-Kawada J, Fujioka S, Tsuboi Y. Perry Disease: Bench to Bedside Circulation and a Team Approach. Biomedicines 2024; 12:113. [PMID: 38255218 PMCID: PMC10813069 DOI: 10.3390/biomedicines12010113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/28/2023] [Accepted: 01/02/2024] [Indexed: 01/24/2024] Open
Abstract
With technological applications, especially in genetic testing, new diseases have been discovered and new disease concepts have been proposed in recent years; however, the pathogenesis and treatment of these rare diseases are not as well established as those of common diseases. To demonstrate the importance of rare disease research, in this paper we focus on our research topic, Perry disease (Perry syndrome). Perry disease is a rare autosomal dominant neurodegenerative disorder clinically characterized by parkinsonism, depression/apathy, weight loss, and respiratory symptoms including central hypoventilation and central sleep apnea. The pathological classification of Perry disease falls under TAR DNA-binding protein 43 (TDP-43) proteinopathies. Patients with Perry disease exhibit DCTN1 mutations, which is the causative gene for the disease; they also show relatively uniform pathological and clinical features. This review summarizes recent findings regarding Perry disease from both basic and clinical perspectives. In addition, we describe technological innovations and outline future challenges and treatment prospects. We discuss the expansion of research from rare diseases to common diseases and the importance of collaboration between clinicians and researchers. Here, we highlight the importance of researching rare diseases as it contributes to a deeper understanding of more common diseases, thereby opening up new avenues for scientific exploration.
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Affiliation(s)
| | | | | | - Yoshio Tsuboi
- Department of Neurology, Fukuoka University, Fukuoka 814-0180, Japan; (T.M.); (J.Y.-K.); (S.F.)
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Pietracupa S, Bologna M, Tommasin S, Berardelli A, Pantano P. The Contribution of Neuroimaging to the Understanding of Essential Tremor Pathophysiology: a Systematic Review. THE CEREBELLUM 2021; 21:1029-1051. [PMID: 34657271 DOI: 10.1007/s12311-021-01335-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/10/2021] [Indexed: 12/14/2022]
Abstract
Essential tremor (ET) is one of the most common movement disorders. Over the last 10 years, magnetic resonance imaging (MRI) has shed light on the structural and functional abnormalities possibly involved in ET pathophysiology. In this systematic review, we aimed to identify the cortical and subcortical structures involved and the role that different brain areas play in the pathophysiology of motor and non-motor ET features. We found that structural (grey and white matter) cerebellar damage and connectivity alterations between the cerebellum and various cortical areas play a role in both motor and non-motor symptoms of ET. In particular, many studies found an association between MRI findings and non-motor symptoms.
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Affiliation(s)
| | - Matteo Bologna
- IRCCS Neuromed, Via Atinense 18, Pozzilli, IS, Italy.,Department of Human Neuroscience, Sapienza University of Rome, Rome, Italy
| | - Silvia Tommasin
- Department of Human Neuroscience, Sapienza University of Rome, Rome, Italy
| | - Alfredo Berardelli
- IRCCS Neuromed, Via Atinense 18, Pozzilli, IS, Italy.,Department of Human Neuroscience, Sapienza University of Rome, Rome, Italy
| | - Patrizia Pantano
- IRCCS Neuromed, Via Atinense 18, Pozzilli, IS, Italy.,Department of Human Neuroscience, Sapienza University of Rome, Rome, Italy
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4
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Louis ED, Faust PL. Essential Tremor Within the Broader Context of Other Forms of Cerebellar Degeneration. THE CEREBELLUM 2021; 19:879-896. [PMID: 32666285 DOI: 10.1007/s12311-020-01160-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Essential tremor (ET) has recently been reconceptualized by many as a degenerative disease of the cerebellum. Until now, though, there has been no attempt to frame it within the context of these diseases. Here, we compare the clinical and postmortem features of ET with other cerebellar degenerations, thereby placing it within the broader context of these diseases. Action tremor is the hallmark feature of ET. Although often underreported in the spinocerebellar ataxias (SCAs), action tremors occur, and it is noteworthy that in SCA12 and 15, they are highly prevalent, often severe, and can be the earliest disease manifestation, resulting in an initial diagnosis of ET in many cases. Intention tremor, sometimes referred to as "cerebellar tremor," is a common feature of ET and many SCAs. Other features of cerebellar dysfunction, gait ataxia and eye motion abnormalities, are seen to a mild degree in ET and more markedly in SCAs. Several SCAs (e.g., SCA5, 6, 14, and 15), like ET, follow a milder and more protracted disease course. In ET, numerous postmortem changes have been localized to the cerebellum and are largely confined to the cerebellar cortex, preserving the cerebellar nuclei. Purkinje cell loss is modest. Similarly, in SCA3, 12, and 15, Purkinje cell loss is limited, and in SCA12 and 15, there is preservation of cerebellar nuclei and relative sparing of other central nervous system regions. Both clinically and pathologically, there are numerous similarities and intersection points between ET and other disorders of cerebellar degeneration.
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Affiliation(s)
- Elan D Louis
- Department of Neurology and Therapeutics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Phyllis L Faust
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY, USA
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5
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Kakei S, Manto M, Tanaka H, Mitoma H. Pathophysiology of Cerebellar Tremor: The Forward Model-Related Tremor and the Inferior Olive Oscillation-Related Tremor. Front Neurol 2021; 12:694653. [PMID: 34262527 PMCID: PMC8273235 DOI: 10.3389/fneur.2021.694653] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 05/18/2021] [Indexed: 01/14/2023] Open
Abstract
Lesions in the Guillain-Mollaret (G-M) triangle frequently cause various types of tremors or tremor-like movements. Nevertheless, we know relatively little about their generation mechanisms. The deep cerebellar nuclei (DCN), which is a primary node of the triangle, has two main output paths: the primary excitatory path to the thalamus, the red nucleus (RN), and other brain stem nuclei, and the secondary inhibitory path to the inferior olive (IO). The inhibitory path contributes to the dentato-olivo-cerebellar loop (the short loop), while the excitatory path contributes to the cerebrocerebellar loop (the long loop). We propose a novel hypothesis: each loop contributes to physiologically distinct type of tremors or tremor-like movements. One type of irregular tremor-like movement is caused by a lesion in the cerebrocerebellar loop, which includes the primary path. A lesion in this loop affects the cerebellar forward model and deteriorates its accuracy of prediction and compensation of the feedback delay, resulting in irregular instability of voluntary motor control, i.e., cerebellar ataxia (CA). Therefore, this type of tremor, such as kinetic tremor, is usually associated with other symptoms of CA such as dysmetria. We call this type of tremor forward model-related tremor. The second type of regular tremor appears to be correlated with synchronized oscillation of IO neurons due, at least in animal models, to reduced degrees of freedom in IO activities. The regular burst activity of IO neurons is precisely transmitted along the cerebellocerebral path to the motor cortex before inducing rhythmical reciprocal activities of agonists and antagonists, i.e., tremor. We call this type of tremor IO-oscillation-related tremor. Although this type of regular tremor does not necessarily accompany ataxia, the aberrant IO activities (i.e., aberrant CS activities) may induce secondary maladaptation of cerebellar forward models through aberrant patterns of long-term depression (LTD) and/or long-term potentiation (LTP) of the cerebellar circuitry. Although our hypothesis does not cover all tremors or tremor-like movement disorders, our approach integrates the latest theories of cerebellar physiology and provides explanations how various lesions in or around the G-M triangle results in tremors or tremor-like movements. We propose that tremor results from errors in predictions carried out by the cerebellar circuitry.
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Affiliation(s)
- Shinji Kakei
- Department of Anatomy and Physiology, Jissen Women's University, Tokyo, Japan
| | - Mario Manto
- Service de Neurologie, Médiathèque Jean Jacquy, CHU-Charleroi, Charleroi, Belgium
- Service des Neurosciences, University of Mons, Mons, Belgium
| | - Hirokazu Tanaka
- Faculty of Information Technology, Tokyo City University, Tokyo, Japan
| | - Hiroshi Mitoma
- Department of Medical Education, Tokyo Medical University, Tokyo, Japan
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Lenka A, Louis ED. Do We Belittle Essential Tremor by Calling It a Syndrome Rather Than a Disease? Yes. Front Neurol 2020; 11:522687. [PMID: 33178097 PMCID: PMC7594521 DOI: 10.3389/fneur.2020.522687] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 08/26/2020] [Indexed: 12/23/2022] Open
Abstract
Essential tremor (ET) is among the most prevalent neurological diseases. Appreciation in recent years of a richer tremor phenomenology, additional motor and non-motor features, variability in the natural course of tremor, associations with a host of other neurological conditions, and etiological and pathophysiological heterogeneity have resulted in general awareness of the clinical richness of ET. Along with this evolving view of ET have surfaced several conundrums regarding nomenclature. One of these is whether ET should be labeled a "syndrome" or "disease." Here, we revisit the classical definitions of "syndrome" and "disease" and discuss ET in this context. Considering the characteristics of "disease" and "syndrome" and evaluating the characteristics of ET, it seems to fit more into the "disease" construct. There are several reasons: There is considerable knowledge of the underlying etiologies and pathophysiology of ET, in numerous studies ET has been linked with other neurological conditions, the condition is progressive and deteriorative, and therapeutic approaches are grounded in an understanding of disease mechanisms and its associated neuroanatomy. Moreover, the etiological-pathological-clinical heterogeneity suggests that ET should be regarded as a "family of diseases" more appropriately termed "the essential tremors." This nomenclatural issue is not a mere matter of words; public health implications are numerous. A condition with the label "syndrome" may not be recognized as a serious problem, may be plagued by diminished public awareness, and may not garner funds for research that a condition with the label "disease" or "diseases" would. ET should be regarded as a family of diseases.
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Affiliation(s)
- Abhishek Lenka
- Department of Neurology, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Elan D. Louis
- Department of Neurology, University of Texas Southwestern, Dallas, TX, United States
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7
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Nietz A, Krook-Magnuson C, Gutierrez H, Klein J, Sauve C, Hoff I, Christenson Wick Z, Krook-Magnuson E. Selective loss of the GABA Aα1 subunit from Purkinje cells is sufficient to induce a tremor phenotype. J Neurophysiol 2020; 124:1183-1197. [PMID: 32902350 DOI: 10.1152/jn.00100.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Previously, an essential tremor-like phenotype has been noted in animals with a global knockout of the GABAAα1 subunit. Given the hypothesized role of the cerebellum in tremor, including essential tremor, we used transgenic mice to selectively knock out the GABAAα1 subunit from cerebellar Purkinje cells. We examined the resulting phenotype regarding impacts on inhibitory postsynaptic currents, survival rates, gross motor abilities, and expression of tremor. Purkinje cell specific knockout of the GABAAα1 subunit abolished all GABAA-mediated inhibition in Purkinje cells, while leaving GABAA-mediated inhibition to cerebellar molecular layer interneurons intact. Selective loss of GABAAα1 from Purkinje cells did not produce deficits on the accelerating rotarod, nor did it result in decreased survival rates. However, a tremor phenotype was apparent, regardless of sex or background strain. This tremor mimicked the tremor seen in animals with a global knockout of the GABAAα1 subunit, and, like essential tremor in patients, was responsive to ethanol. These findings indicate that reduced inhibition to Purkinje cells is sufficient to induce a tremor phenotype, highlighting the importance of the cerebellum, inhibition, and Purkinje cells in tremor.NEW & NOTEWORTHY Animals with a global knockout of the GABAAα1 subunit show a tremor phenotype reminiscent of essential tremor. Here we show that selective knockout of GABAAα1 from Purkinje cells is sufficient to produce a tremor phenotype, although this tremor is less severe than seen in animals with a global knockout. These findings illustrate that the cerebellum can play a key role in the genesis of the observed tremor phenotype.
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Affiliation(s)
- Angela Nietz
- University of Minnesota, Department of Neuroscience, Minneapolis, Minnesota
| | | | - Haruna Gutierrez
- University of Minnesota, Department of Neuroscience, Minneapolis, Minnesota
| | - Julia Klein
- University of Minnesota, Department of Neuroscience, Minneapolis, Minnesota
| | - Clarke Sauve
- University of Minnesota, Department of Neuroscience, Minneapolis, Minnesota
| | - Isaac Hoff
- University of Minnesota, Department of Neuroscience, Minneapolis, Minnesota
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8
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Louis ED, Faust PL. Essential tremor: the most common form of cerebellar degeneration? CEREBELLUM & ATAXIAS 2020; 7:12. [PMID: 32922824 PMCID: PMC7427947 DOI: 10.1186/s40673-020-00121-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 08/03/2020] [Indexed: 02/07/2023]
Abstract
Background The degenerative cerebellar ataxias comprise a large and heterogeneous group of neurological diseases whose hallmark clinical feature is ataxia, and which are accompanied, to variable degrees, by other features that are attributable to cerebellar dysfunction. Essential tremor (ET) is an exceptionally common neurological disease whose primary motor feature is action tremor, although patients often manifest intention tremor, mild gait ataxia and several other features of cerebellar dysfunction. Main Body In this paper, we review the abundant evidence derived from clinical, neuroimaging and postmortem studies, linking ET to cerebellar dysfunction. Furthermore, we review the combination of clinical, natural history and postmortem features suggesting that ET is neurodegenerative. We then compare the prevalence of ET (400 – 900 cases per 100,000) to that of the other cerebellar degenerations (ranging from <0.5 – 9 cases per 100,000, and in composite likely to be on the order of 20 cases per 100,000) and conclude that ET is 20 to 45 times more prevalent than all other forms of cerebellar degeneration combined. Conclusion Given the data we present, it is logical to conclude that ET is, by far, the most common form of cerebellar degeneration.
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Affiliation(s)
- Elan D Louis
- Department of Neurology and Therapeutics, University of Texas Southwestern, Dallas, TX USA
| | - Phyllis L Faust
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY USA
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Amrutkar DV, Dyhring T, Jacobsen TA, Larsen JS, Sandager-Nielsen K. Anti-Tremor Action of Subtype Selective Positive Allosteric Modulators of GABAA Receptors in a Rat Model of Essential Tremors. THE CEREBELLUM 2020; 19:265-274. [DOI: 10.1007/s12311-020-01106-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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10
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Retinal nerve fiber layer thickness in patients with essential tremor and Parkinson’s disease. JOURNAL OF SURGERY AND MEDICINE 2019. [DOI: 10.28982/josam.661757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Louis ED, Hernandez N, Dyke JP, Ma RE, Dydak U. In Vivo Dentate Nucleus Gamma-aminobutyric Acid Concentration in Essential Tremor vs. Controls. THE CEREBELLUM 2019; 17:165-172. [PMID: 29039117 DOI: 10.1007/s12311-017-0891-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Despite its high prevalence, essential tremor (ET) is among the most poorly understood neurological diseases. The presence and extent of Purkinje cell (PC) loss in ET is the subject of controversy. PCs are a major storehouse of central nervous system gamma-aminobutyric acid (GABA), releasing GABA at the level of the dentate nucleus. It is therefore conceivable that cerebellar dentate nucleus GABA concentration could be an in vivo marker of PC number. We used in vivo 1H magnetic resonance spectroscopy (MRS) to quantify GABA concentrations in two cerebellar volumes of interest, left and right, which included the dentate nucleus, comparing 45 ET cases to 35 age-matched controls. 1H MRS was performed using a 3.0-T Siemens Tim Trio scanner. The MEGA-PRESS J-editing sequence was used for GABA detection in two cerebellar volumes of interest (left and right) that included the dentate nucleus. The two groups did not differ with respect to our primary outcome of GABA concentration (given in institutional units). For the right dentate nucleus, [GABA] in ET cases = 2.01 ± 0.45 and [GABA] in controls = 1.86 ± 0.53, p = 0.17. For the left dentate nucleus, [GABA] in ET cases = 1.68 ± 0.49 and [GABA] controls = 1.80 ± 0.53, p = 0.33. The controls had similar dentate nucleus [GABA] in the right vs. left dentate nucleus (p = 0.52); however, in ET cases, the value on the right was considerably higher than that on the left (p = 0.001). We did not detect a reduction in dentate nucleus GABA concentration in ET cases vs. CONTROLS One interpretation of the finding is that it does not support the existence of PC loss in ET; however, an alternative interpretation is the observed pattern could be due to the effects of terminal sprouting in ET (i.e., collateral sprouting from surviving PCs making up for the loss of GABA-ergic terminals from PC degeneration). Further research is needed.
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Affiliation(s)
- Elan D Louis
- Department of Neurology, Yale School of Medicine, Yale University, LCI 710, 15 York Street, PO Box 208018, New Haven, CT, 06520-8018, USA. .,Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, USA. .,Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, CT, USA.
| | - Nora Hernandez
- Department of Neurology, Yale School of Medicine, Yale University, LCI 710, 15 York Street, PO Box 208018, New Haven, CT, 06520-8018, USA
| | - Jonathan P Dyke
- Department of Radiology, Weill Cornell Medical College, New York, NY, USA
| | - Ruoyun E Ma
- School of Health Sciences, Purdue University, West Lafayette, IN, USA.,Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Ulrike Dydak
- School of Health Sciences, Purdue University, West Lafayette, IN, USA.,Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, USA
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12
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[Magnetic resonance-guided focused ultrasound : A new option for tremor treatment]. DER NERVENARZT 2018; 90:408-411. [PMID: 30406441 DOI: 10.1007/s00115-018-0627-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abstract
We describe two cases of typical essential tremor with aspartic acidemia and mildly increased concentrations of plasma glutamic acid. Although this is a preliminary report, we emphasize the possibility of using amino acids, including aspartic acid, as biomarkers for the detection of essential tremor.
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Affiliation(s)
- Shiroh Miura
- Division of Respirology, Neurology and Rheumatology, Department of Medicine, Kurume University School of Medicine
| | - Ryuta Fujioka
- Department of Food and Nutrition, Beppu University Junior College
| | - Takayuki Taniwaki
- Division of Respirology, Neurology and Rheumatology, Department of Medicine, Kurume University School of Medicine
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14
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Zheng X, Vieira Campos A, Ordieres-Meré J, Balseiro J, Labrador Marcos S, Aladro Y. Continuous Monitoring of Essential Tremor Using a Portable System Based on Smartwatch. Front Neurol 2017; 8:96. [PMID: 28360883 PMCID: PMC5350115 DOI: 10.3389/fneur.2017.00096] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 02/27/2017] [Indexed: 12/31/2022] Open
Abstract
INTRODUCTION Essential tremor (ET) shows amplitude fluctuations throughout the day, presenting challenges in both clinical and treatment monitoring. Tremor severity is currently evaluated by validated rating scales, which only provide a timely and subjective assessment during a clinical visit. Motor sensors have shown favorable performances in quantifying tremor objectively. METHODS A new highly portable system was used to monitor tremor continuously during daily lives. It consists of a smartwatch with a triaxial accelerometer, a smartphone, and a remote server. An experiment was conducted involving eight ET patients. The average effective data collection time per patient was 26 (±6.05) hours. Fahn-Tolosa-Marin Tremor Rating Scale (FTMTRS) was adopted as the gold standard to classify tremor and to validate the performance of the system. Quantitative analysis of tremor severity on different time scales is validated. RESULTS Significant correlations were observed between neurologist's FTMTRS and patient's FTMTRS auto-assessment scores (r = 0.84; p = 0.009), between the device quantitative measures and the scores from the standardized assessments of neurologists (r = 0.80; p = 0.005) and patient's auto-evaluation (r = 0.97; p = 0.032), and between patient's FTMTRS auto-assessment scores day-to-day (r = 0.87; p < 0.001). A graphical representation of four patients with different degrees of tremor was presented, and a representative system is proposed to summarize the tremor scoring at different time scales. CONCLUSION This study demonstrates the feasibility of prolonged and continuous monitoring of tremor severity during daily activities by a highly portable non-restrictive system, a useful tool to analyze efficacy and effectiveness of treatment.
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Affiliation(s)
- Xiaochen Zheng
- Department of Industrial Engineering, Technical University of Madrid , Madrid , Spain
| | | | - Joaquín Ordieres-Meré
- Department of Industrial Engineering, Technical University of Madrid , Madrid , Spain
| | - Jose Balseiro
- University Hospital of Getafe, Getafe , Madrid , Spain
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Lau CI, Lin CC, Chen HJ, Wang HC, Chen WH, Liang JA. Increased risk of essential tremor in migraine: A population-based retrospective cohort study. PLoS One 2017; 12:e0173586. [PMID: 28288163 PMCID: PMC5348003 DOI: 10.1371/journal.pone.0173586] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 02/22/2017] [Indexed: 11/18/2022] Open
Abstract
Purpose To examine the long-term risk of essential tremor (ET) in migraine. Methods Using population-based administrative data from a subset of the National Health Insurance Research Database (NHIRD) of Taiwan, we identified 22,696 newly diagnosed migraineurs (mean age 44.5 years) and a matched migraine-free cohort of 90,784 individuals in the period 2000–2008. Multivariable Cox proportional hazards regression analysis was conducted for assessing the ET risk for the migraine cohort compared to the migraine-free cohort. Results After adjusting for covariates, the migraine cohort had a 1.83-fold increased risk (95% CI 1.50–2.23) of subsequent ET in comparison to the migraine-free cohort (8.97 vs. 4.81 per 10,000 person-years). In the subgroup analysis, patients with migraine were associated with higher risks of ET, regardless of gender, age or the existence of comorbidities. Conclusion Our findings demonstrated an association between migraine and ET, suggesting a possible shared pathophysiology underpinning both disorders.
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Affiliation(s)
- Chi-Ieong Lau
- Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.,Division of Clinical Neurology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Institute of Cognitive Neuroscience, University College London, Queen Square, London, United Kingdom.,College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan
| | - Che-Chen Lin
- Management Office for Health Data, China Medical University Hospital, Taichung, Taiwan.,Healthcare Service Research Center (HSRC), Taichung Veterans General Hospital, Taichung, Taiwan
| | - Hsuan-Ju Chen
- Management Office for Health Data, China Medical University Hospital, Taichung, Taiwan.,College of Medicine, China Medical University, Taichung, Taiwan
| | - Han-Cheng Wang
- Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.,College of Medicine, Taipei Medical University, Taipei, Taiwan.,College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wei-Hung Chen
- Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.,College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Ji-An Liang
- Graduate Institute of Clinical Medical Science, School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.,Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan
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Effect of Primidone on Dentate Nucleus γ-Aminobutyric Acid Concentration in Patients With Essential Tremor. Clin Neuropharmacol 2016; 39:24-8. [PMID: 26757316 DOI: 10.1097/wnf.0000000000000127] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES It is not known whether current use of the medication primidone affects brain γ-aminobutyric acid (GABA) concentrations. This is an important potential confound in studies of the pathophysiology of essential tremor (ET), one of the most common neurological diseases. We compared GABA concentrations in the dentate nucleus in 6 ET patients taking primidone versus 26 ET patients not taking primidone. METHODS (1)H magnetic resonance spectroscopy was performed using a 3.0-T Siemens Tim Trio scanner. The MEGA-PRESS J-editing sequence was used for GABA detection in 2 cerebellar volumes of interest (left and right) that included the dentate nucleus. RESULTS The right dentate GABA concentration was similar in the 2 groups (2.21 ± 0.46 [on primidone] vs 1.93 ± 0.39 [not on primidone], P = 0.15), as was the left dentate GABA concentration (1.61 ± 0.35 [on primidone] vs 1.67 ± 0.34 [not on primidone], P = 0.72). The daily primidone dose was not associated with either right or left dentate GABA concentrations (P = 0.89 and 0.76, respectively). CONCLUSIONS We did not find a difference in dentate GABA concentrations between 6 ET patients taking daily primidone and 26 ET patients not taking primidone. Furthermore, there was no association between daily primidone dose and dentate GABA concentration. These data suggest that it is not necessary to exclude ET patients on primidone from magnetic resonance spectroscopy studies of dentate GABA concentration, and if assessment of these concentrations was to be developed as a biomarker for ET, primidone usage would not confound interpretation of the results.
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Ferrucci R, Bocci T, Cortese F, Ruggiero F, Priori A. Cerebellar transcranial direct current stimulation in neurological disease. CEREBELLUM & ATAXIAS 2016; 3:16. [PMID: 27595007 PMCID: PMC5010772 DOI: 10.1186/s40673-016-0054-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 08/25/2016] [Indexed: 01/05/2023]
Abstract
Several studies have highlighted the therapeutic potential of transcranial direct current stimulation (tDCS) in patients with neurological diseases, including dementia, epilepsy, post-stroke dysfunctions, movement disorders, and other pathological conditions. Because of this technique’s ability to modify cerebellar excitability without significant side effects, cerebellar tDCS is a new, interesting, and powerful tool to induce plastic modifications in the cerebellum. In this report, we review a number of interesting studies on the application of cerebellar tDCS for various neurological conditions (ataxia, Parkinson’s disease, dystonia, essential tremor) and the possible mechanism by which the stimulation acts on the cerebellum. Study findings indicate that cerebellar tDCS is a promising therapeutic tool in treating several neurological disorders; however, this method’s efficacy appears to be limited, given the current data.
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Affiliation(s)
- Roberta Ferrucci
- Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122 Milan, Italy ; Dipartimento di Scienze della Salute, Università degli Studi di Milano, via Rudinì 8, 20142 Milan, Italy
| | - Tommaso Bocci
- Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122 Milan, Italy
| | - Francesca Cortese
- Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122 Milan, Italy
| | - Fabiana Ruggiero
- Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122 Milan, Italy
| | - Alberto Priori
- Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122 Milan, Italy ; Dipartimento di Scienze della Salute, Università degli Studi di Milano, via Rudinì 8, 20142 Milan, Italy ; III Clinica Neurologica, Polo Ospedaliero San Paolo, via Rudinì 8, 20142 Milan, Italy
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A Variable Oscillator Underlies the Measurement of Time Intervals in the Rostral Medial Prefrontal Cortex during Classical Eyeblink Conditioning in Rabbits. J Neurosci 2016; 35:14809-21. [PMID: 26538651 DOI: 10.1523/jneurosci.2285-15.2015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
UNLABELLED We were interested in determining whether rostral medial prefrontal cortex (rmPFC) neurons participate in the measurement of conditioned stimulus-unconditioned stimulus (CS-US) time intervals during classical eyeblink conditioning. Rabbits were conditioned with a delay paradigm consisting of a tone as CS. The CS started 50, 250, 500, 1000, or 2000 ms before and coterminated with an air puff (100 ms) directed at the cornea as the US. Eyelid movements were recorded with the magnetic search coil technique and the EMG activity of the orbicularis oculi muscle. Firing activities of rmPFC neurons were recorded across conditioning sessions. Reflex and conditioned eyelid responses presented a dominant oscillatory frequency of ≈12 Hz. The firing rate of each recorded neuron presented a single peak of activity with a frequency dependent on the CS-US interval (i.e., ≈12 Hz for 250 ms, ≈6 Hz for 500 ms, and≈3 Hz for 1000 ms). Interestingly, rmPFC neurons presented their dominant firing peaks at three precise times evenly distributed with respect to CS start and also depending on the duration of the CS-US interval (only for intervals of 250, 500, and 1000 ms). No significant neural responses were recorded at very short (50 ms) or long (2000 ms) CS-US intervals. rmPFC neurons seem not to encode the oscillatory properties characterizing conditioned eyelid responses in rabbits, but are probably involved in the determination of CS-US intervals of an intermediate range (250-1000 ms). We propose that a variable oscillator underlies the generation of working memories in rabbits. SIGNIFICANCE STATEMENT The way in which brains generate working memories (those used for the transient processing and storage of newly acquired information) is still an intriguing question. Here, we report that the firing activities of neurons located in the rostromedial prefrontal cortex recorded in alert behaving rabbits are controlled by a dynamic oscillator. This oscillator generated firing frequencies in a variable band of 3-12 Hz depending on the conditioned stimulus-unconditioned stimulus intervals (1 s, 500 ms, 250 ms) selected for classical eyeblink conditioning of behaving rabbits. Shorter (50 ms) and longer (2 s) intervals failed to activate the oscillator and prevented the acquisition of conditioned eyelid responses. This is an unexpected mechanism to generate sustained firing activities in neural circuits generating working memories.
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Gallea C, Popa T, García-Lorenzo D, Valabregue R, Legrand AP, Marais L, Degos B, Hubsch C, Fernández-Vidal S, Bardinet E, Roze E, Lehéricy S, Vidailhet M, Meunier S. Intrinsic signature of essential tremor in the cerebello-frontal network. Brain 2015; 138:2920-33. [PMID: 26115677 DOI: 10.1093/brain/awv171] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 04/24/2015] [Indexed: 11/12/2022] Open
Abstract
Essential tremor is a movement disorder characterized by tremor during voluntary movements, mainly affecting the upper limbs. The cerebellum and its connections to the cortex are known to be involved in essential tremor, but no task-free intrinsic signatures of tremor related to structural cerebellar defects have so far been found in the cortical motor network. Here we used voxel-based morphometry, tractography and resting-state functional MRI at 3 T to compare structural and functional features in 19 patients with essential tremor and homogeneous symptoms in the upper limbs, and 19 age- and gender-matched healthy volunteers. Both structural and functional abnormalities were found in the patients' cerebellum and supplementary motor area. Relative to the healthy controls, the essential tremor patients' cerebellum exhibited less grey matter in lobule VIII and less effective connectivity between each cerebellar cortex and the ipsilateral dentate nucleus. The patient's supplementary motor area exhibited (i) more grey matter; (ii) a lower amplitude of low-frequency fluctuation of the blood oxygenation level-dependent signal; (iii) less effective connectivity between each supplementary motor area and the ipsilateral primary motor hand area, and (iv) a higher probability of connection between supplementary motor area fibres and the spinal cord. Structural and functional changes in the supplementary motor area, but not in the cerebellum, correlated with clinical severity. In addition, changes in the cerebellum and supplementary motor area were interrelated, as shown by a correlation between the lower amplitude of low-frequency fluctuation in the supplementary motor area and grey matter loss in the cerebellum. The structural and functional changes observed in the supplementary motor area might thus be a direct consequence of cerebellar defects: the supplementary motor area would attempt to reduce tremor in the motor output by reducing its communication with M1 hand areas and by directly modulating motor output via its corticospinal projections.See Raethjen and Muthuraman (doi:10.1093/brain/awv238) for a scientific commentary on this article.
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Affiliation(s)
- Cécile Gallea
- 1 Centre de NeuroImagerie de Recherche - Institut du Cerveau et de la Moelle épinière, ICM, Paris, France 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France
| | - Traian Popa
- 1 Centre de NeuroImagerie de Recherche - Institut du Cerveau et de la Moelle épinière, ICM, Paris, France 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France
| | - Daniel García-Lorenzo
- 1 Centre de NeuroImagerie de Recherche - Institut du Cerveau et de la Moelle épinière, ICM, Paris, France 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France
| | - Romain Valabregue
- 1 Centre de NeuroImagerie de Recherche - Institut du Cerveau et de la Moelle épinière, ICM, Paris, France 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France
| | | | - Lea Marais
- 1 Centre de NeuroImagerie de Recherche - Institut du Cerveau et de la Moelle épinière, ICM, Paris, France 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France
| | - Bertrand Degos
- 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France 6 AP-HP, Hôpital de la Pitié Salpêtrière, Département de Neurologie, Paris, France
| | - Cecile Hubsch
- 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France 6 AP-HP, Hôpital de la Pitié Salpêtrière, Département de Neurologie, Paris, France
| | - Sara Fernández-Vidal
- 1 Centre de NeuroImagerie de Recherche - Institut du Cerveau et de la Moelle épinière, ICM, Paris, France 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France
| | - Eric Bardinet
- 1 Centre de NeuroImagerie de Recherche - Institut du Cerveau et de la Moelle épinière, ICM, Paris, France 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France
| | - Emmanuel Roze
- 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France 6 AP-HP, Hôpital de la Pitié Salpêtrière, Département de Neurologie, Paris, France
| | - Stéphane Lehéricy
- 1 Centre de NeuroImagerie de Recherche - Institut du Cerveau et de la Moelle épinière, ICM, Paris, France 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France 7 AP-HP, Hôpital de la Pitié Salpêtrière, Département de Neuroradiologie, Paris, France
| | - Marie Vidailhet
- 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France 6 AP-HP, Hôpital de la Pitié Salpêtrière, Département de Neurologie, Paris, France
| | - Sabine Meunier
- 2 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Paris, France 3 CNRS, UMR 7225, Paris, France 4 Inserm, U 1127, Paris, France
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Clark LN, Ye X, Liu X, Mirzozoda K, Louis ED. Genetic analysis of ten common degenerative hereditary ataxia loci in patients with essential tremor. Parkinsonism Relat Disord 2015; 21:943-7. [PMID: 26077168 DOI: 10.1016/j.parkreldis.2015.06.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 05/01/2015] [Accepted: 06/03/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND To investigate the association of repeat expansion size in 10 common degenerative hereditary ataxia genes with essential tremor. These genes were spinocerebellar ataxia (SCA)-1 (ATXN1), SCA-2 (ATXN2), SCA-3 (ATXN3), SCA-6 (CACNA1A), SCA-7 (ATXN7), SCA-8 (ATXN8OS), SCA-10 (ATXN10), SCA-12 (PPP2R2B), SCA-17 (TBP) and dentatorubral-pallidolysian atrophy (DRPLA) (ATN1). METHODS Genetic analysis of repeat size in 10 degenerative hereditary ataxia loci was performed in 323 essential tremor patients and 299 controls enrolled at Columbia University. To test for differences in the allele distribution between patients and controls, a CLUMP analysis was performed. RESULTS None of the essential tremor patients had a repeat expansion in the intermediate or pathogenic range. Significant differences in the distribution of repeats in the 'normal' range for SCA2 and SCA8 (both p ≤ 0.02) were observed between essential tremor patients and controls. CONCLUSIONS Our study suggests that pathogenic repeat expansions in SCA loci are not associated with essential tremor.
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Affiliation(s)
- L N Clark
- Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY, USA; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
| | - X Ye
- Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
| | - X Liu
- Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
| | - K Mirzozoda
- Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
| | - E D Louis
- Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA; Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, USA.
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Are patients with limb and head tremor a clinically distinct subtype of essential tremor? Can J Neurol Sci 2015; 42:181-6. [PMID: 25857448 DOI: 10.1017/cjn.2015.23] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Essential tremor (ET) is the most common tremor disorder in adults. In addition to upper limbs, the tremor in ET may also involve head, jaw, voice, tongue, and trunk. Though head tremor (HT) is commonly present in patients with ET, large comparative studies of ET patients with HT (HT+) and without HT (HT-) are few. METHODS To determine whether ET with HT is a distinct clinical subtype by comparing ET patients with and without HT, a chart review of 234 consecutive patients with ET attending the neurology clinics of the National Institute of Mental Health and Neurosciences, India, was done. A movement disorder specialist confirmed the diagnosis of ET in all patients using the National Institutes of Health collaborative genetic criteria. RESULTS HT was present in 44.4% of the patients. Comparison between HT+ and HT- showed that the HT+ group patients: (1) were older, (2) had later onset of tremor, (3) had unimodal distribution of age at onset with a single peak in the fifth decade, (4) had more frequent voice tremor, and (5) were more likely to have mild cervical dystonia. HT was part of presenting symptoms in nearly two thirds of the ET patients and in the rest it was detected during clinical examination. CONCLUSIONS Several demographic and clinical variables suggest that ET patients with HT have a distinct clinical phenotype.
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