Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Peak dose dyskinesia is a major problem in the treatment of parkinsonian patients with levodopa and yet this remains the best pharmacological agent for treating the condition. The hypothesis which this research set out to test was that thalamotomy in the area of the thalamus which receives the input from the medial segment of the globus pallidus would decrease or prevent the dyskinesia. A well established primate model of parkinsonism was used. Eight monkeys (Macaca fascicularis) were rendered parkinsonian with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Regular dosing with levodopa or apomorphine reliably resulted in peak dose dyskinesia. Thalamotomy was carried out using a radiofrequency electrode. To ensure that the appropriate area of the thalamus was targeted, that is the area receiving the pallidal input, an anatomical tracing study was carried out. The anterograde anatomical tracer horseradish peroxidase, covalently bound to wheatgerm agglutinin, was injected into the medial segment of the globus pallidus bilaterally in three monkeys. The target site for thalamotomy was accurately worked out from the tracings obtained. Chorea was usually abolished and always reduced by a thalamotomy in the pallidal terminal territory. This result was obtained after 10 thalamotomies: 4 animals receiving bilateral lesions, with an interval between operations, and 2 animals undergoing unilateral surgery. Lesions in three control sites were carried out and had no permanent effect on chorea. The effect of lesions in other areas was also assessed. Dystonia was not relieved by any thalamic lesion. Thalamotomy is a long established procedure used to help parkinsonian tremor. Appropriately placed thalamotomy should be considered for the relief of disabling peak dose dyskinesia, which is predominantly choreic, in parkinsonian patients on otherwise successful levodopa therapy.
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PMID:The use of thalamotomy in the treatment of levodopa-induced dyskinesia. 158 Jan 97

To study the demographic and clinical correlates of essential tremor (ET), we analyzed a comprehensive database of 350 patients evaluated at the Movement Disorders Clinic at Baylor College of Medicine from 1982 to 1989. The age at onset of tremor showed bimodal distribution for both male and female patients, with peaks in 2nd and 6th decades. ET appeared most frequently in hands, followed by head, voice, tongue, leg, and trunk. Half of the patients (47%) had associated dystonia, including cervical dystonia, writer's cramp, spasmodic dysphonia, and cranial dystonia, and 20% of the patients had associated parkinsonism. At least one 1st-degree relative of 62.5% of ET patients reported tremor. Alcohol relieved tremor in 2/3 of ET patients. Sixty-eight percent of patients who had adequate follow-up improved with propranolol, and 72% with primidone. There was no significant difference in various clinical variables between the 219 patients with familial ET and 131 with sporadic ET. Patients with early-onset ET were more likely to have hand involvement and associated dystonia than patients with late-onset ET. Dystonia was more frequently associated with mild ET than with severe ET. Patients with low-frequency tremor were older and had more head but less hand involvement than patients with high-frequency tremor. The lack of relevant differences between ET subgroups suggests that, despite variable expression, ET represents a single disease entity.
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PMID:Essential tremor: clinical correlates in 350 patients. 162 Mar 68

Tardive dyskinesia (TD) is a consequence of chronic neuroleptic therapy. It is an irregular stereotyped movement disorder that is usually choreic in appearance, and is subject to temporary volitional control. Dystonia, akathisia, and tics are uncommon variants of the classic tardive syndrome. Characteristic clinical features including amelioration by action, augementation by distraction, partial volitional suppressibility, and lack of subjective distress help differentiate TD from other movement disorders such as resting tremor, Huntington's disease, spontaneous dyskinesias, and abnormal movements accompanying psychiatric illnesses.
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PMID:Recognition and differential diagnosis of tardive dyskinesia. 257 70

Voluntary suppressibility of abnormal movements is helpful in the classification of movement disorders because this ability appears to be a common component of tics. However, there has been no systematic study of voluntary suppressibility in other movement disorders. We have therefore assessed 146 patients with tremors and dyskinetic disorders as to their ability to suppress movements by mental concentration. Patients were videotaped while trying to stop their movements, and the length of time they could suppress their abnormal movements was recorded. One hundred percent (10 of 10) of patients with tics could suppress movements for an average of 2.5 min. Two percent (1 of 50) of essential tremor patients could suppress the tremor, and the tremor of 24% (12 of 50) was made worse by mental concentration. Eighty percent (4 of 5) of neuroleptic-induced tremor could be improved mentally. Seventy percent (35 of 50) of patients with parkinsonian tremor could voluntarily diminish their tremor for an average of 48 s. Fifty percent (8 of 16) of chorea (tardive dyskinesia, Huntington's disease, postencephalitic) was reduced. Dystonia was suppressible in 20% (3 of 15). It is concluded that movement disorders besides tics can be voluntarily suppressed and that suppressibility should not be used to classify movement disorders. Tics, however, are easier to suppress and can be suppressed for a longer time.
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PMID:Volitional control of involuntary movements. 273 7

Spastic dysphonia is a syndrome often producing a strain-strangle voice. We have previously classified most of these patients as having focal laryngeal dystonia, a disorder of central motor processing. In a study of 1,280 cases of dystonia registered at the Dystonia Clinical Research Center at the Columbia-Presbyterian Medical Center, we found 110 patients who had vocal cord involvement. These patients had historical information evaluated for age of onset (mean 34.6 years), duration of symptoms (mean 13.8 years), sex (1.4:1 female to male) family history (positive in 23%), and primary (66%) and secondary (34%) etiology; neurological evaluation for other dystonic involvement (25% with segmental cranial involvement, 23% with generalized dystonia) or tremor (irregular 23%, regular 6% on EMG). Treatment options were evaluated and included speech therapy, psychotherapy, biofeedback (with limited success), systemic medication (limited success except in abductor cases), nerve section (with late failure rate), and the use of botulinum toxin (improvement in all 34 injected patients).
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PMID:Clinical and laboratory characteristics of focal laryngeal dystonia: study of 110 cases. 337 39

Twenty patients with tongue tremor associated with essential tremor are reported. Patients were unaware of the tongue tremor, and voice disturbance was a complaint in only one patient. Three patients had an isolated tongue tremor. Hand tremor was present in 16 patients. Dystonia, myoclonus, and tremor of other body parts were present in some patients. Three patients had a mild-to-moderate dysarthria. The frequency of tongue tremor (4-8 Hz) was identical to hand tremor. The intravenous infusion of ethanol suppressed tongue tremor. Therapy with propranolol, primidone, or clonazepam also reduced tongue tremor amplitude. Tongue tremor is a common finding in some essential tremor patients but often there are no symptoms.
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PMID:Essential tongue tremor. 350 57

Thirty-one patients with Wilson's disease were evaluated with detailed neurologic and medical examinations. Mean age (+/- SD) at onset was 21 +/- 5 years and at examination was 28 +/- 6 years. Of the 90% of patients who were first treated with penicillamine, 31% deteriorated initially despite therapy, and half never recovered to pretherapy baseline. At the time of our evaluations, the most common neurologic findings were dysarthria (97%), dystonia (65%), dysdiadochokinesia (58%), rigidity (52%), gait and postural abnormalities (42%), and tremor (32%). Chorea and dementia were rare. Twenty-two patients underwent magnetic resonance imaging. All but one of the 19 symptomatic patients had abnormal scans. The three asymptomatic patients had normal scans. Most lesions were seen in the caudate, putamen, subcortical white matter, midbrain, and pons. Generalized brain atrophy was also common. Lesions were less common in the thalamus, cerebellar vermis, midbrain tegmentum, globus pallidus, red nucleus, and dentate nucleus. Dystonia and bradykinesia correlated with putamen lesions, and dysarthria correlated with both putamen and caudate lesions.
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PMID:Clinical assessment of 31 patients with Wilson's disease. Correlations with structural changes on magnetic resonance imaging. 382 91

Twenty index patients with hereditary essential tremor and their kindreds were studied to define the phenotype of this condition. Ninety-three first degree and 38 more distant relatives were examined; 53 definite and 18 possible secondary cases were identified. The age of tremor onset was bimodally distributed with a median at approximately 15 years. Segregation analysis indicated autosomal dominant inheritance and penetrance was virtually complete by the age of 65 years. There were no examples of the disease skipping a generation. Men and women were affected in equal proportions. About 50% of cases were alcohol responsive. In the majority of families alcohol responsiveness was either consistently present or did not occur, but in 20% of kindreds definite heterogeneity of responsiveness was encountered within each family. The typical phenotype was a mild symmetrical postural tremor of the upper limbs. Tremor of the legs, head, facial muscles, voice, jaw and tongue occurred but never in isolation and rest, task specific (e.g. primary writing tremor) and primary orthostatic tremors were not found. Head tremor was invariably mild and 75% was of a 'no-no' type. Dystonia (e.g. torticollis and writer's cramp) were not encountered, a finding which strongly suggests that many previous studies of 'essential tremor' were contaminated by cases of idiopathic or hereditary torsion dystonia. No association with Parkinson's disease was found but classical migraine occurred in approximately 26% of cases and co-segregated with tremor. The severity of arm tremor (assessed using a clinical rating scale and by scoring tremor in Archimedes spirals) and disability increased with advancing age and increasing tremor duration, but there was no correlation between age at tremor onset and either tremor severity or disability. Men and women were affected with equal severity. The sex of the affected parent had no influence on the severity of tremor or the degree of disability experienced by an affected child. Disability commenced in the second decade and progressively increased. All the index patients and 59% of the definite secondary cases had tremor induced disabilities. Eighty-five percent of index patients and 38% of secondary cases also reported some degree of social handicap. Twenty-five percent of index patients and 12% of secondary cases had been compelled to change jobs or retire. Biological fitness was normal.
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PMID:A study of hereditary essential tremor. 792 67

We reviewed the database of the Dystonia Clinic at the University of Kansas Medical Center for patients with dystonia and tremor. Of 296 patients with idiopathic dystonia, 24 had dystonic tremor, 20 with cervical dystonia had an isolated head-nodding tremor, two patients with writer's cramp had ipsilateral hand tremor, and two patients with generalized dystonia had arm tremor. Eight patients, all with cervical dystonia, had essential tremor that preceded the onset of their dystonia.
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PMID:Essential tremor and dystonia. 823 62

Leigh syndrome (LS) is the clinical prototype of a genetically-determined mitochondrial encephalopathy. Twenty-two of 34 patients with LS had evidence of a movement disorder (MD). Dystonia, the most common MD, was present in 19 cases, rigidity in 4, tremor in 2, chorea in 2, hypokinesia in 2, myoclonus in 1, and tics in 1. Dystonia was most commonly multifocal at onset and showed progression in six patients. In half of the cases an enzymatic defect was detected, most commonly cytochrome C oxidase. The neuroradiologic findings showed prominent basal ganglia lesions in 20/21 patients. Putamen, caudate, substantia nigra and globus pallidus were involved in this order of frequency. This experience was reflected in a literature review encompassing 284 cases of LS. However, only 26.4% had MD. Eleven patients, including one of our cases, presented as the primary torsion dystonia phenotype. There are clinical and pathological similarities between LS and other metabolic diseases affecting the central nervous system. The enhanced vulnerability of the nervous system to metabolic stress and the resemblance in the distribution of the pathology of these diverse conditions suggests a common pathogenetic mechanism. An excitotoxin-mediated mechanism is favored, one which might account for the frequent involvement of the basal ganglia in LS.
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PMID:Disorders of movement in Leigh syndrome. 839 42


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