Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027066 (myoclonus)
 4,275 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

Any attempt to classify and to understand the basic mechanism underlying the neurological symptoms as pyramidal and/or sensitive, should start from the fundamental laws of nervous system functioning: 1) the law of reciprocal innervation of Sherrington; 2) the law of hierarchy of levels of Jackson and 3) the law of supersensitivity of deafferented structures of Cannon. Paresis on one side, Jacksonian jerks on the other side represent two opposite conditions known respectively as negative and positive symptoms of corticomotor involvement. Unluckly involuntary movements cannot be explained with these three laws. They are the clinical expression of the disorganization and disintegration of functions: a true disregulation unrespectful of laws and general principles. They must be considered as the result of conflicts of antagonist functions controlling each other, i.e. tremor, chorea, myoclonus, torsion spasm etc. The author emphasizes the clinical-descriptive aspect of the problem.
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PMID:[Involuntary movements]. 269

A case of familial juvenile Alzheimer's disease with apallic state at the relatively early stage and various neurological features was reported. A 33-year-old woman showed a progressive dementia followed by apallic state at the relatively early stage, and died of cardiac failure at the age of 45. Neurological examination disclosed chorea, myoclonus, rigidity, pyramidal sign, and generalized convulsion. Neuropathologically, extensive senile changes such as senile plaques, neurofibrillary tangles, and granurovascular degenerations were observed in the brain, chiefly in the cerebral cortex and limbic system. The present case was characterized by a severe neuronal loss in the subcortical gray matter such as the caudate nucleus, dentate nucleus, substantia nigra, and thalamus as well as a marked myelin loss and axonal damages in the cerebral white matter. This case suggested a combination of multisystemic degeneration and a primary degeneration of the cerebral white matter. The additional peculiar aspects in this case were the senile plaques and amyloid angiopathy in the cerebellar cortex, and the senile plaques and grumose degeneration in the cerebellar dentate nucleus. In the clinicopathological standpoint, the apallic state in this case could be attributed to a severe degeneration of the cerebral white matter in addition to the cerebral cortical deterioration. Furthermore, the occurrence of chorea and myclonus might be contributed to the severe degeneration of the caudate nucleus and to the degeneration of the dentate nucleus, particularly to the grumose degeneration, respectively.
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PMID:[A case of familial juvenile Alzheimer's disease with apallic state at the relatively early stage and various neurological features--a clinicopathological study]. 279 15

An autopsy case of a 66 year-old woman is reported. She developed personality change and psychotic symptoms at the age of 58. She began to show gait disturbance and forgetfullness at the age of 60. She was admitted to Okayama University Hospital at the age of 61, when she showed personality change, dementia, cerebellar sings and chorea like involuntary movement. The illness progressed slowly and she died of septicemia at the age of 66. At autopsy brain weighed 990 g. Macroscopically, the atrophy of the brain stem was severe, and the cerebellum was slightly atrophic. Microscopically, the globus pallidus was almost intact, but the degeneration involved dentate nuclei, their projections, red nucleus and the subthalamic nuclei, so this case was considered to be a case of pseudo-Huntington form of dentatorubropallidoluysian atrophy, proposed by Hirayama. The most striking feature of this case was marked atrophy of the brain stem and her intense familial history. Investigation of her familial history revealed that there were 18 affected cases in 5 successive generations. Their onset of the disease varied from the age of 10 to 60 years old. Cases of juvenile onset showed myoclonus and convulsion as the initial symptoms, and convulsion as the initial symptoms, and those of presenile onset showed dementia, cerebellar ataxia and chorea like involuntary movement. And in some of these cases it was proved by NMR-CT that their brain stem were small. We discussed the meaning of the atrophy of the brain stem in these cases and the difference of the symptoms between the cases of juvenile onset and the cases of presenile onset.
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PMID:[An autopsy case of dentatorubropallidoluysian atrophy showing marked atrophy of the brain stem]. 296 93

Experiments are described in which the gamma-aminobutyric acid (GABA) antagonist bicuculline was injected into the lentiform complex of conscious monkeys. Injections into either the lateral segment of the globus pallidus, or the medial part of the putamen, gave rise to chorea of the contralateral limbs and/or orofacial region. Control injections of vehicle alone were without effect. Injections of bicuculline into the lateral part of the putamen gave rise to contralateral myoclonus. The chorea produced by lateral pallidal or medial putaminal injections was virtually indistinguishable from the dyskinesia (chorea/ballism) which has been shown, in previous studies, to be induced by injection of GABA antagonists into the subthalamic nucleus. It is proposed that the primary site of action of the GABA antagonist in producing chorea, in the present studies, was the lateral segment of the globus pallidus. The mode of action is suggested to be interruption of GABAergic transmission from the striatum to the lateral pallidal segment. Since this also occurs in Huntington's disease, it is proposed that experimental chorea induced by this method in the monkey may be a useful model of the dyskinesia seen in Huntington's disease in man. Loss of influence of inhibitory striatopallidal fibres would lead to abnormally increased activity of lateral pallidal neurons. These in turn project to the subthalamic nucleus, upon which they have an inhibitory action. Dyskinesia is thus produced by physiological inhibition of the subthalamic nucleus, whose destruction, both in man and the monkey, is known to produce ballism. It is proposed that ballism and chorea share common neural mechanisms, both involving the loss of influence of the subthalamic nucleus on the medial segment of the globus pallidus.
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PMID:Chorea and myoclonus in the monkey induced by gamma-aminobutyric acid antagonism in the lentiform complex. The site of drug action and a hypothesis for the neural mechanisms of chorea. 317 91

We report three members of a single family who developed a newly described combination of myoclonus and chorea in association with mild ataxia. The occurrence of this and related syndromes suggests that inherited, slowly progressive myoclonus, chorea, and dystonia, alone or in combination, should be viewed as a spectrum of hyperkinetic involuntary movements, and that each motor component may represent variable expression of the same genetic defect.
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PMID:Hereditary myoclonus and chorea: the spectrum of hereditary nonprogressive hyperkinetic movement disorders. 350 55

This review concentrated on the more recent findings of investigations into the functional anatomy and pathophysiology of movement disorders. Attempts were made to provide explanations for rigidity, bradykinesia, and tremor. What little is known of the pathophysiology of chorea, tics, and dystonia is discussed. Greater information is available to allow pathophysiologic classification of different types of myoclonus.
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PMID:The pathophysiology of movement disorders. 624 55

The descriptive aspects of all types of movement disorders and their related syndromes and terminologies used in the literature are reviewed and described. This comprises the features of (a) movement disorders secondary to neurological diseases affecting the extrapyramidal motor system, such as: athetosis, chorea, dystonia, hemiballismus, myoclonus, tremor, tics and spasm, (b) drug induced movement disorders, such as: akathisia, akinesia, hyperkinesia, dyskinesias, extrapyramidal syndrome, and tardive dyskinesia, and (c) abnormal movements in psychiatric disorders, such as: mannerism, stereotyped behaviour and psychomotor retardation. It is intended to bring about a more comprehensive overview of these movement disorders from a phenomenological perspective, so that clinicians can familiarize with these features for diagnosis. Some general statements are made in regard to some of the characteristics of movement disorders.
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PMID:Clinical features of movement disorders. 662 43

In patients suffering from tick-borne encephalitis development of epileptic seizures, Kozhevnikov's epilepsy, Jackson's epilepsy, myoclonus-epilepsy, chorea-epilepsy Hunt's myoclonic dyssynergy and various hyperkineses without general convulsions was observed. It was found that a particular place in the structure of the convulsive syndrome was occupied by Kozhevnikov's epilepsy which was not so frequently encountered in other diseases. This is, probably, due to a particular vulnerability of the motor structures, mainly, at the spinal level, at which the final motor response is formed.
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PMID:[Tick-borne encephalitis and epilepsy]. 679 56

A 15 year old boy was evaluated in the psychiatric emergency room for the acute onset of "confusion,"insomnia, headache, and shaking of one week's duration. Two days later hallucinations, formication and a movement disorder emerged characterized by action tremor, myoclonus, chorea and ataxia. Further history revealed inhalation of gasoline for its euphoric effects. Plasma lead levels were in the toxic range. Chelation therapy reversed the clinical symptoms. Behavioral changes and a movement disorder in the context of gasoline inhalation are highly suggestive of organic lead encephalopathy. Recognition of this syndrome is important as chelation therapy is effective.
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PMID:Organic lead encephalopathy: behavioral change and movement disorder following gasoline inhalation. 705 7


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