Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0013421 (dystonia)
 8,418 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This review considers the evidence for possible involvement of central nervous system pacemaker neurons in several clinical disorders of movement. Two basic types of tremor are discussed from this point of view, i.e., 4--7/sec parkinsonian tremor, of possible thalamocortical origin, and 7--11/sec essential tremor of possible olivo-cerebellar origin. The importance of motor programs and abnormalities in their utilization are considered with reference to the loss of motor function in parkinsonism (? loss of motor programs), and the inappropriate release of such programs as a possible basis for the involuntary movements seen in other movement disorders, such as chorea, athetosis, dystonia, and hemiballismus. The possible role of pacemaker neurons controlling such programs is considered. Finally, the subject of locomotion and the pacemaker model of the spinal locomotor pattern generator for stepping are considered in relation to clinical disorders of gait. While critical evidence is lacking for pacemaker inovlvement in any of these disorders, their possible role is emphasized.
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PMID:Possible involvement of central pacemakers in clinical disorders of movement. 35 Jun 32

Anticonvulsants cause dyskinesias more commonly than has been appreciated. Diphenylhydantoin (DPH), carbamazepine, primidone, and phenobarbitone may cause asterixis. DPH, but not other anticonvulsants, may cause orofacial dyskinesias, limb chorea, and dystonia in intoxicated patients. These dyskinesias are similar to those caused by neuroleptic drugs and may be related to dopamine antagonistic properties possessed by DPH.
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PMID:Anticonvulsant-induced dyskinesias: a comparison with dyskinesias induced by neuroleptics. 101 Oct 32

A variety of hyperkinetic movement disorders has been associated with the use of neuroleptics (dopamine receptor blocking drugs), but tardive tremor has not been previously documented. We describe five patients in whom tremor occurred after chronic treatment with neuroleptics, was aggravated by and persisted after neuroleptic withdrawal, and improved after treatment with the dopamine depleting drug tetrabenazine. This involuntary oscillatory movement, with a frequency range of 3-5 Hz, was most prominent during maintenance of a posture, but was also present at rest and during a goal-directed movement. The tremor was accompanied by other tardive movement disorders, including akathisia, chorea, dystonia, myoclonus, and stereotypy. There was no family history or other explanation for tremor in these patients. We suggest that this hitherto unreported movement disorder is best termed "tardive tremor."
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PMID:Tardive tremor. 134 52

Levodopa-induced dyskinesias (LID) in Parkinson's disease (PD) may be classified into three main categories: "On" dyskinesias, diphasic dyskinesias (DD), and "off" periods. The study of 168 parkinsonian patients showed that about half (n = 84) showed one pattern of LID only. A combination of two was present in 68, and 16 had the three presentation patterns. A fairly good correlation between type of dyskinesia and presentation pattern was established. Chorea, myoclonus, and dystonic movements occurred during the "on" period. Dystonic postures, particularly affecting the feet, were mainly present in the "off" period, but a few patients had a diphasic presentation. Repetitive stereotyped movements of the lower limbs always corresponded to DD. Acute pharmacological tests using dopamine agonists (subcutaneous apomorphine 3-8 mg; intravenous lisuride 0.1-0.15 mg) and dopamine antagonists (intravenous sulpiride 200-400 mg and intravenous chlorpromazine 25 mg) were performed in 40 patients. Dopamine agonists enhanced "on" dyskinesias and markedly reduced or abolished "off" period dystonia and DD. Dopamine antagonists reduced all types of LID but usually aggravated parkinsonism. These clinical and pharmacological results indicate that LID in PD are a heterogeneous phenomenon difficult to explain on the basis of a single pathophysiological mechanism.
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PMID:Levodopa-induced dyskinesias in Parkinson's disease: clinical and pharmacological classification. 135 58

Seventy individuals with ataxia telangiectasia were studied: 29 females and 41 males with an age range of 2 to 42 years. The majority (43/68) presented by 3 years of age with truncal ataxia. All had progressive, handicapping neurological symptoms exhibiting ataxia (70/70), ocular motor apraxia (70/70), an impassive face (70/70), dysarthria (70/70), chorea (68/70), dystonia (55/70) and peripheral neuropathy (50/70). Clinical immune deficiency was present in 43 of 70 patients. Ocular telangiectasia were seen in all but one case and excessive thinness in 54 of 70. The mean age of loss of walking was 10 years and of writing 8 years. All 60 tested showed increased sensitivity to ionizing irradiation, 43 of 48 had an elevated alpha-fetoprotein level and 14 of 21 had an immunoglobulin deficiency. Although there was a marked variation in disease findings sibs were always similar. The heterogeneity seen seems at odds with the unilocus linkage of ataxia telangiectasia to 11q23.
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PMID:Ataxia telangiectasia in the British Isles: the clinical and laboratory features of 70 affected individuals. 137 28

Twenty patients with propionic acidemia were reviewed retrospectively. Two groups were identified: those who presented in the first week of life (11 patients) or after the neonatal period (9 patients). The early onset of disease had a much higher death rate (hazard ratio: 7.52) and all patients in this group were mentally retarded (IQ < or = 60). Movement disorder was common in both groups. Of the early-onset group, 3 patients had mild chorea or dystonia. Four in the late-onset group had a severe movement disorder. In the late onset group, cranial computed tomography disclosed transient basal ganglia lucencies following an episode of metabolic decompensation; however, no disturbance in amine neurotransmitter metabolite concentrations were found in the cerebrospinal fluid.
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PMID:Neurologic outcome of propionic acidemia. 141 75

In a series of 225 patients with astrocytomas (grades I-IV) of the basal ganglia and the thalamus, 20 had a movement disorder. In all patients the histological diagnosis was verified by stereotactic biopsy. Tremor was observed in twelve patients, dystonia in eight, chorea in three, and chorea/ballismus and myoclonus in one. The tumour involved the thalamus in 16 patients. Corticospinal tract dysfunction was evident in 70% of the patients with movement disorders and in 73% of those without. Demographic, clinical, histological and neuroradiological data of the patients with a movement disorder were compared with the data of patients without. CT data yielded no differences with respect to the involvement of anatomical structures. Movement disorders were significantly associated with low-grade astrocytomas.
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PMID:Movement disorders in astrocytomas of the basal ganglia and the thalamus. 2264 3

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

Certain genetic aspects of the movement disorders, including parkinsonism, dystonia, ataxia, chorea, tics, and others, are reviewed. Clinical features, diagnostic techniques, and laboratory tests of newly recognized inherited syndromes are discussed. Progress in linkage analysis in several disorders is also presented.
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PMID:Genetic considerations in movement disorders. 162 59

To assess the need for a regional expertise in movement disorders, the numbers of patients, clinic visits, and medication changes for a new movement disorder clinic were recorded. During 3 1/2 years, 355 patients were seen, with 1,329 clinic visits. Idiopathic Parkinson's disease was the most common diagnosis, comprising 36% of the population, followed by dystonia (17%), tremor (12%), parkinsonism (i.e., Parkinson's plus syndromes, drug-induced parkinsonism, etc.) (10%), chorea (10%), Tourette's syndrome (6.5%), and tardive dyskinesia (3.4%). Distribution of follow-up visits was similar, with Parkinson's disease (52%) being most frequent and Tourette's syndrome (3.1%) least frequent. The relative utilization of medical care by each patient group was assessed by determining the number of medication changes and the number of clinic visits per follow-up year. No differences in these measures were found using a one-way analysis of variance. Of the Parkinson's disease patients, 67% had Hoehn and Yahr stages III-IV and 77% of the clinic visits were made by this subgroup. When considered in light of the prevalence of each of the diseases, these data show a need for an expertise in movement disorders for a population base of the size we have served.
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PMID:Profile of patients enrolled in a new movement disorder clinic. 175 52


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