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

Heavily T2-weighted high-field MR images provide a unique opportunity for the evaluation of the extrapyramidal motor system. The images are affected by the presence of small amounts of naturally occurring paramagnetic substances--principally iron--that delineate the neostriatum (caudate and putamen), globus pallidus, red nucleus, substantia nigra, and dentate nucleus, primarily by a decrease in signal secondary to the T2* effect. Movement disorders are associated with either increased or decreased signal or both in these structures, depending on the pathologic process. In the initial evaluation of 113 patients with a variety of movement disorders, good correlation of imaging abnormalities can be made with a simplified schema of the extrapyramidal pathways and a system of classification of abnormal movements, parkinsonism/tremor, dystonia, chorea, myoclonus, and hemiballismus. Parkinsonisms are characterized by abnormalities of the cortico-ponto-cerebello-dentato-rubro-thalamo-cortico-spinal tract or the nigrostriatal tract. Dystonias are characterized by abnormalities of the neostriatum predominantly affecting the putamen. Choreas are also characterized by abnormalities of the neostriatum but predominantly affecting the caudate nucleus. Hemiballismus is characterized by lesions affecting the subthalamic nucleus or associated pathway.
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PMID:Study of movement disorders and brain iron by MR. 244 Feb 91

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

Torsion dystonia is a movement disorder of unknown etiology characterized by loss of control of voluntary movements appearing as sustained muscle contractions and/or abnormal postures. Dystonic movements can be caused by lesions in the basal ganglia, drugs, or gene defects. Several hereditary forms have been described, most of which have autosomal dominant transmission with variable expressivity. In the Ashkenazi Jewish population the defective gene frequency is about 1/10,000. Here, linkage analysis using polymorphic DNA and protein markers has been used to locate a gene responsible for susceptibility to dystonia in a large, non-Jewish kinship. Affected members of this family have a clinical syndrome similar to that found in the Jewish population. This dystonia gene (ITD1) shows tight linkage with the gene encoding gelsolin, an actin binding protein, and appears by multipoint linkage analysis to lie in the q32-q34 region of chromosome 9 between ABO and D9S26, a region that also contains the locus for dopamine-beta-hydroxylase.
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PMID:Human gene for torsion dystonia located on chromosome 9q32-q34. 257 73

Rats with an inherited movement disorder (dystonic, dt), their phenotypically normal littermates, and normal unrelated controls were studied using a metabolic mapping technique, 2-deoxyglucose autoradiography. This approach was used to identify potential sites of abnormality underlying the movement disorder, as no morphological abnormalities using light and electron microscopic techniques have been identified in this mutation. There was a significant overall glucose utilization (GU) reduction in the dt rats and their littermate controls when they were at rest and not displaying abnormal movements. Conversion of GU values to standard scores showed abnormalities in dt compared with both control groups in the following areas: deep cerebellar nuclei, locus coeruleus, pontine gray, ventrolateral-ventromedial thalamic complex, nucleus of the third nerve, lateral habenula, and basolateral amygdala. Littermates were different from nonlittermates in several regions, including the dentate and red nuclei. A study of relative GU performed in animals displaying dystonic movements also showed abnormalities in the deep cerebellar nuclei and locus coeruleus, and in the red nucleus, external cuneate, and medial septum. Correlations computed for GU in pairs of regions with known anatomical connections suggested that cerebellar, substantia nigra, and basal ganglia efferents may be abnormal. These studies complement existing biochemical and neuropharmacological data which show abnormalities in the cerebellum of the dt rat. Additionally, the function of brain stem and even basal ganglia nuclei is affected in this mutant, perhaps as a consequence of abnormal cerebellar activity. The partial effects in the littermates suggest that abnormalities in only a few regions are not sufficient to produce the movement disorder, and a gene dose effect may exist.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Regional cerebral glucose utilization reveals widespread abnormalities in the motor system of the rat mutant dystonic. 258 66

Ten consecutive patients with a progressive pan-autonomic failure of the Shy-Drager syndrome were investigated. Movement disorders of the vocal cords were examined with a fiber-optic laryngoscope as well as a video-recorder. Moderate to severe vocal cord paralysis was present in five of ten patients. The vocal cords were almost immobile during inspiration, while there was no limitation of the adduction during phonation. In two cases, grade of vocal cord paralysis was asymmetric. One patient developed peculiar twisting-like dystonic movements of the vocal cord. Polygraphic studies revealed that SaO2 was lowered in spite of tachypnea during sleep. In two cases, the expiratory flow volume curve in effort-dependent portion near TLC showed a plateau and the inspiratory part of the curve also showed a plateau indicating constant flow. These functional disorders suggest an upper airway obstruction probably due to the vocal cord dysfunction. There was no vocal cord paralysis in two patients who had neither snore nor stridor. Development of a severe vocal cord dysfunction usually manifested itself clinically as stridor, snore or respiratory failure requiring tracheostomy. There was little information on the pathology of the vagal nerves and nuclei supplying motor control to the laryngeal muscles. The mechanism of the selective involvement of abductor muscle (posterior muscle) of the vocal cord (Gerhardt syndrome) remains unsolved. Vocal cord paralysis should be looked for since it can result in respiratory failure leading to death.
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PMID:[Bilateral abductor vocal cord paralysis (Gerhardt syndrome) in the Shy-Drager syndrome]. 260 29

Metoclopramide, a dopamine-2 receptor antagonist used for various gastrointestinal disorders, may cause or exacerbate a variety of extrapyramidal movement disorders. To draw attention to the frequent occurrence of metoclopramide-induced movement disorders, we identified and studied 16 patients who had been exposed to this neuroleptic. The average age at onset was 63 years (range, 24 to 85 years), and women outnumbered men 3 to 1. Tardive dyskinesia was the most common movement disorder (n = 10 [63%]). Five patients had metoclopramide-induced parkinsonism, 1 patient had tardive dystonia, and 1 patient had akathisia. The average duration of exposure prior to onset of movement disorders was 12 months (range, 1 day to 4 years). Therapy was continued for an average of 6 months (range, 1 day to 2 years) after the onset of symptoms, reflecting clinical nonrecognition of the movement disorder and its relationship to metoclopramide. To prevent persistent and disabling movement disorders, long-term use of metoclopramide should be avoided, and patients should be carefully observed for potential neurologic reactions.
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PMID:Metoclopramide-induced movement disorders. Clinical findings with a review of the literature. 268 75

Tardive dystonia is a rare movement disorder. We outline the development of tardive dystonia in a young schizophrenic, and demonstrate the importance of applying a double-blind, placebo-controlled, cross-over trial of any putative successful treatment.
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PMID:Tardive dystonia. The benefits of time. 257 26

The movement disorder investigated in these studies has some features in common with human idiopathic dystonia, and information obtained in these studies may be of potential clinical benefit. The present experimental results indicated that peptidergic stimulation of the LC resulted in a NE-mediated inhibition of cerebellar Purkinje cells located at terminals of the ceruleo-cerebellar pathway. However, it is not certain as to the following: (a) what receptors were stimulated by the ACTH N-terminal fragments at the LC that resulted in this disorder; (b) whether NE, released onto Purkinje cell synapses located at terminals of the ceruleo-cerebellar pathway, did indeed cause the long-term depression at Purkinje cell synapses (previously described by others) that resulted in the long duration of the movement disorder; (c) whether the inhibition of inhibitory Purkinje cells resulted in disinhibition or increased excitability of the unilateral cerebellar fastigial or interpositus nuclei, the output targets of the Purkinje cell axons, that may have been an important contributing factor to this disorder. These questions are currently being investigated.
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PMID:A dystonia-like syndrome after neuropeptide (MSH/ACTH) stimulation of the rat locus ceruleus. 284 Aug 7

The role of neuroleptics in causing the tardive dyskinesia syndrome is controversial. To properly assess the contribution of drugs as the etiology of dyskinesias, the effects of aging, the natural history of psychosis, and characteristics of spontaneous dyskinesias must be considered. Though the buccolinguo-masticatory triad is seen more often in tardive than in spontaneous dyskinesias, these two disorders have many symptoms in common. Other dyskinesias, such as idiopathic and tardive dystonia or tardive Tourette's syndrome and dyskinesias in untreated schizophrenia, are poorly understood. Chronic neuroleptic treatment may only precipitate TD in those already predisposed to develop such movement disorders. Tardive dyskinesia is not a unique movement disorder, but rather spans several clinical and epidemiological phenomena which must be considered in a balanced evaluation of how much of the permanent dyskinesias should be attributed to neuroleptic drugs.
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PMID:Is tardive dyskinesia a unique disorder? 286 Jun 61

About 2.5% of patients treated with neuroleptic drugs develop acute dystonia within 48 h of commencing therapy. The symptoms remit on drug withdrawal or following anticholinergic therapy. Acute dystonia can also be reliably induced in many primate species by neuroleptic treatment with comparable time course, symptomatology and pharmacological characteristics to those observed in man. In general, New World monkeys appear more susceptible to acute dystonia than Old World primates. It is at present not clear whether all primates, including man, would exhibit dystonia if a sufficiently high dose of neuroleptic was administered. Alternatively, some unknown, possibly species-specific or even genetic, factors may determine an individual's susceptibility to develop dystonia. Use of a rodent model of dystonia might enable more detailed analysis of biochemical correlates of dystonic behaviour. Whilst rodents do not exhibit overt dystonic behaviour after neuroleptic treatment, they may develop oral dyskinesias which bear a close pharmacological similarity to dystonia in man and primates. However, it is not known whether chewing induced by neuroleptic drugs in rats resembles acute dystonia in primates or whether this is another movement disorder possibly unique to rodent species. The pathophysiology of acute dystonia remains unknown, but may involve striatal dopaminergic and cholinergic function. In view of the close similarity between dystonia in man and other primates, studies on the mechanisms whereby neuroleptic drugs cause acute dystonic reactions in monkeys may give some clues to the pathogenesis of spontaneous dystonia in man.
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PMID:Acute dystonia induced by neuroleptic drugs. 287 78


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