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)

To elucidate the pathophysiological features of childhood onset dopa-responsive dystonia (DRD) we used a variety of quantitative analysis techniques to evaluate aspects of reflex- and voluntary motor control in two brothers with this disorder. The observed patterns were compared with those obtained in patients with adult onset Parkinson's disease (PD) and Huntington's disease (HD). In both brothers onset of the disease was in the first decade. Both responded either to treatment with L-Dopa or a combination of L-Dopa with trihexiphenidyl. Neurophysiological studies revealed slowing of different upper extremity voluntary motor activities and a low frequency postural tremor similar to results in other basal ganglia disorders including PD. In contrast to adult onset PD, fastest isometric voluntary index finger contractions did not show the typical kinetic tremor oscillations superimposed on the force trajectories. Also, different to adult PD, no impairment of stance regulating reflexes or saccadic and smooth pursuit eye movements was found in DRD. Magnetoelectrical stimulation of motor cortex showed normal efferent cortical spinal activity. Data indicate that like in other basal ganglia diseases slowing of voluntary motor activity is also a constant feature in DRD. DRD patients show, however, a clear difference to the pattern of motor abnormalities obtainable in PD. Both the pattern of motor control abnormalities is different, and the longlasting effect. In contrast to PD the pathophysiological mechanism in DRD possibly involves a lack of maturation of dopaminergic substantia nigra neurons rather than a degenerative process.
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PMID:Motor control in childhood onset dopa-responsive dystonia (Segawa syndrome). 251 99

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

There are a number of different relationships among aging, psychosis and movement disorders, most of which have been proposed to involve the neurotransmitter dopamine. Dopamine content and dopamine receptors have been shown to decrease with age, which may relate to the time of onset of different motor and psychotic disorders, as well as to the appearance of these disorders. For example, some so-called senile movement disorders, such as senile tremor and senile chorea, may relate to alterations in dopaminergic transmission with age, as might the general findings of increased slowing of movements and mildly increased rigidity with age, although it is not clear how common some of these changes are in the medically healthy elderly. Decrease in dopamine with age may also be associated with the findings that choreiform and psychotic disorders (which have been proposed to be related to excess dopaminergic activity) tend to predominate at younger ages, whereas parkinsonism is more common at later ages. Certain findings support this notion, such as the appearance of both dyskinesia and psychosis in patients treated with L-dopa, the finding that psychosis may be less common in patients with later-onset Huntington's disease, and the fact that neuroleptic-induced parkinsonism is often more severe in the elderly. However, the situation is more complicated than this, because there are a number of phenomena that do not fit the pattern, including the observation of an increased incidence of tardive dyskinesia in the elderly. Age-related changes in other transmitters are undoubtedly important in both movements disorders and psychosis, and even dopamine has been proposed to have both trophic and toxic properties over the aging process. In general, care is warranted in the use of any psychotropic medications in the elderly, because there can be widespread and often unpredictable effects of these drugs on both motor and mental function.
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PMID:Association of psychosis and movement disorders in the elderly. 289 37

Patients with Huntington's disease (HD) and relatives at risk were examined with respect to their capacity to produce rapid voluntary motor activity. For this purpose, the fastest possible self-paced single isometric forefinger extensions and the fastest alternating forefinger movements were tested. In addition to these fastest voluntary performances, the time course of spontaneous hyperkinetic finger movements and the peak frequency of finger and hand tremor were analysed as a measure of the temporal characteristics of involuntary movements. Comparison of these parameters in HD patients and individuals at risk with age and sex-matched normal controls revealed a significant slowing of all types of contractions or movements in the majority (up to 95%) of the patients and in up to 40% of the relatives at risk. Reaction times were only slightly prolonged, and the abnormalities of the movement parameters showed no correlation with detailed psychometric data. Hence it is unlikely that the disturbance in the execution of rapid motor acts is due to dementia. Tremor was also slower than normal and the hyperkinesias were still slower than the fastest voluntary contractions. It appears from this study that slowness of motor performance is not only evident in Parkinson's disease but may represent a more general dysfunction in basal ganglia disease.
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PMID:Impairment of rapid movement in Huntington's disease. 295 6

The corticomotoneurone pathways were examined in 21 patients with movement disorders, using the technique of percutaneous electrical stimulation of the motor cortex. Conduction in these pathways was assessed by measuring the latency to onset of electromyographic activity in the muscles of the upper limb after cortical stimulation. In all patients [five with primary (idiopathic) torsion dystonia and two with secondary (symptomatic) hemidystonia, seven with Huntington's disease, four with essential tremor, and three with Parkinson's disease] central motor conduction was normal. This and other evidence suggests that the origin of the disorder of movement in these conditions lies in the delivery of abnormal motor commands to a normal corticomotoneuronal system.
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PMID:Electrophysiology of the corticomotoneurone pathways in patients with movement disorders. 350 37

The ability of the selective GABA-receptor agonist, progabide, to suppress abnormal involuntary movements was evaluated in a preliminary open pilot study. 17 patients, 10 males and 7 females, aged 10-78 years, with hyperkinetic movement disorders were included in the study. Daily doses of progabide ranged from 900 to 3600 mg (median 2400 mg) corresponding to 14-45 mg/kg (median 45 mg/kg), while the duration of treatment varied from 2 to 52 weeks. Improvement, with a reduction of involuntary movements exceeding 25%, occurred in two of four patients with Gilles de la Tourette's syndrome, and in two of three patients with postanoxic intention myoclonus, while no consistent beneficial effects were registered in ten patients with Huntington's chorea, postanoxic choreoathetosis, torsion dystonia, tardive dyskinesia, action tremor, essential myoclonus, or oro-branchio-respiratory myoclonus.
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PMID:Progabide in the treatment of hyperkinetic extrapyramidal movement disorders. 386 33

GABA mimetics inhibit extrapyramidal DA and ACh neurons and affect an unknown system beyond both DA and ACh receptors, which is involved in extrapyramidal motor outputs. Based on these data, the rationale is discussed for the clinical use of GABA mimetics in Huntington's chorea, parkinsonian tremor, L-DOPA or neuroleptic-induced dyskinesias.
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PMID:The potential of GABA-mimetics in the therapy of extrapyramidal disorders. 610 32

Of 2.1 million patients seen in 25 years at the University College Hospital, Ibadan, Nigeria, only 25 suffered from heredodegenerative disorders of the nervous system. Six patients had hereditary ataxia, 10 essential tremor, 4 Huntington's chorea, 2 ataxia telangiectasia, and 3 Charcot-Marie-Tooth disease.
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PMID:Hereditary neurodegenerative disorders in Nigerian Africans. 623 May 42

The cerebrospinal fluid concentration of hydroxylase cofactor has been measured in patients with Parkinson's disease, the Shy-Drager and Steele-Richardson syndromes, adult onset focal dystonia, essential tremor, Huntington's disease and presenile dementia. The results were compared with age matched controls and low values were demonstrated for all disease groups studied except for focal dystonia.
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PMID:CFS hydroxylase cofactor levels in some neurological diseases. 644 17


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