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)

Dose-related fluctuations in response to L-Dopa such as the "wearing-off" phenomenon are a common side effect of long-term L-Dopa therapy. In a retrospective clinical analysis, 18 of 32 chronically treated parkinsonian fluctuators developed a delay in onset of a beneficial effect induced by single doses of L-Dopa. In these patients, there was a threefold increase in latency from ingestion of the first morning dose to "start-up" of a response (from 0.4 +/- 0.2 to 1.1 +/- 0.3 h) in parallel to a twofold decrease in its duration (from 4.2 +/- 1.1 to 1.7 +/- 0.8 h). Longer durations of illness and of L-Dopa therapy, occurrence of totally ineffective doses, poorer responsiveness to afternoon and evening doses, and early-morning dystonia were more prevalent in this group. In 14 of the 32 parkinsonian fluctuators, monitored "start up" of clinical effect occurred at about an hour after the first morning oral dose of L-Dopa. The dose-induced elevations in plasma L-Dopa levels started after a mean of about 0.5 h and were maximal at 1.25 h. The study suggests that prolongation of "start-up" latencies in response to single doses of L-Dopa is a rather common complication of chronic treatment and may increase patients' disability by further decreasing the duration of daily "on" periods. Causes for this phenomenon are unknown but retarded absorption of orally administered L-Dopa may be important.
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PMID:Delayed onset of responses to single doses of L-dopa in parkinsonian fluctuators on long-term L-dopa therapy. 308 28

A daughter and her mother developed hereditary progressive dystonia with marked diurnal fluctuation (HPD) at the age of 4 and 34, respectively. L-Dopa, tetrahydrobiopterin (BH4) or 5-hydroxytryptophan (5-HTP) was orally administered to them. L-Dopa cured completely their symptoms. 5-HTP as well as BH4 improved their symptoms, especially dystonic movements. Biopterin and 5-hydroxyindoleacetic acid concentrations in CSF increased during BH4 medication. These findings suggest that the serotonergic system of the central nervous system might play some role in the pathogenesis of dystonia in HPD.
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PMID:Effect of tetrahydrobiopterin and 5-hydroxytryptophan on hereditary progressive dystonia with marked diurnal fluctuation: a suggestion of the serotonergic system involvement. 325 39

A classification of child dystonias is proposed as a guide to etiological diagnosis. The analysis of symptoms and signs provides a distinction between dystonia and other involuntary movements: dystonia is a tonic involuntary movement which appears during voluntary activity as a slow and involuntary movement. Two groups of child dystonic syndromes can be distinguished: 1) dystonic syndromes where dystonia is the main neurologic abnormality; they result mainly from toxic and anoxic disorders and from torsion dystonia; 2) dystonic syndromes with associated dystonia and intellectual impairment; they are often familial neurometabolic disorders. Analysis of child dystonias show some common features: a long interval between the causative brain lesion and the onset of dystonia is possible, and may last several years. In neuro-metabolic disorders also dystonia appears after the first year of life, when psycho-motor impairment has already appeared. Etiologic investigations can provide a diagnosis and sometimes a treatment in several varieties of dystonia, e. g. L-Dopa in torsion dystonia, correction of metabolic disturbance in Wilson disease or glutaric aciduria. Genetic counselling should be provided.
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PMID:[Dystonia in the child]. 328 10

In this review, the authors present a critical overview of the historical development, indications, complications, operative techniques, and results of procedures for the alleviation of the major dyskinesias. Emphasis is placed upon recent refinement of technique, particularly stereotaxis, as well as neurophysiologic stimulation and recording, computerized tomographic scanning (CT) and magnetic resonance imaging (MRI). Specific disorders that may be amenable to surgical therapy include spasticity secondary to spinal cord pathology, cerebral palsy, and multiple sclerosis; the tremor and rigidity of Parkinson's disease; essential tremor; dystonia; spasmodic torticollis; post-traumatic and postinfarction intention tremor; cerebral palsy with tremor; hemiballismus; myoclonus; and dyskinesias induced by L-DOPA.
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PMID:Neurosurgical management of spasticity, rigidity, and tremor. 332 80

The authors present a detailed description of transcerebral electrophoresis of L-DOPA conducted in 20 patients aged 9 months to 12 years suffering from a hyperkinetic form of childhood cerebral paralysis. Each patient received 10 sessions. The results of the treatment were assessed by a 5-point score system. Diminution of involuntary movements by 1 point was observed in 1 patient, by 2 points in 10 patients, by 3 points in 7 patients and by 4 points in 1 patient; in one case no positive results were noted. Muscular dystonia and the severity of tonic reflexes decreased in all patients; voluntary movements also improved. Treatment with transcerebral electrophoresis of L-DOPA was well tolerated and was not associated with side-effects.
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PMID:[Transcerebral electrophoresis of L-DOPA in the combined treatment of the hyperkinetic form of infantile cerebral palsy]. 338 15

Six non-human primates received doses of MPTP sufficient to produce a severe parkinsonian syndrome. Levodopa therapy reversed parkinsonian features in all animals, but resulted in dose-dependent choreoathetoid movements of the lower limbs of 3, together with akathisia and dystonia in 2. 'End-of-dose deterioration' was common to all animals, although 'on-off' periods were only seen in 3. Preliminary observations using a clinical rating scale and automatic activity counters demonstrate that both the motor response to levodopa and the complications of therapy are readily quantifiable. We suggest that this is a useful experimental model for testing new strategies in the management of idiopathic Parkinson's disease, particularly with regard to the prevention of drug-induced involuntary movements.
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PMID:Levodopa-induced dyskinesia and response fluctuations in primates rendered parkinsonian with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). 349 42

Twenty children with dystonia sensitive to L-Dopa were identified in a collaborative study by 11 European colleagues. Most cases showed clinical characteristics similar to those described by Segawa (age and mode of onset, marked diurnal fluctuations, predominant limb involvement with no or minimal axial dystonia and, in all cases, dramatic relief of symptoms with small doses of L-Dopa). The typical diurnal fluctuation of symptoms was not observed in 7 children. Significant differences in this respect were noted among affected siblings. There were 9 sporadic and 11 familial cases. The pedigrees observed do not contradict nor clearly confirm Segawa's hypothesis that this might be a dominantly inherited disorder with low penetrance. Response to low doses of L-Dopa was usually dramatic, the benefit was maintained over periods ranging from one to eight years without complications. Recurrence of symptoms on withdrawal was observed in all cases in which it was attempted. These cases represent a form of progressive, presumably hereditary, childhood dystonia, similar to that originally described in Japan and different from dystonia musculorum deformans. The absence of fluctuations of symptoms despite good L-Dopa response and the great variability in the severity of the disorder were important features which will require further study as will the homogeneity of the syndrome, the mode of genetic transmission and the need for persistent L-Dopa treatment in adult life.
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PMID:DOPA-sensitive progressive dystonia of childhood with fluctuations of symptoms--Segawa's syndrome and possible variants. Results of a collaborative study of the European Federation of Child Neurology Societies (EFCNS). 372 92

HVA and 5-HIAA in CSF were determined in five patients with non-fluctuating progressive dystonia before and after treatment with L-Dopa. The response to L-Dopa was unequivocally favourable in one patient. The HVA-level in her CSF was significantly reduced before treatment, whereas in the other four non-responding patients the pre-treatment HVA was normal. It is postulated, that the biochemical delineation of clinical responsiveness to a neurotransmitter may provide useful clues towards the classification of extrapyramidal disease in childhood.
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PMID:Treatment of non-fluctuating progressive dystonia: a neuropharmacological approach. 620 4

We measured the kinetic constants for the unidirectional influx of L-DOPA into red blood cells of patients with Parkinson's disease (seven patients), Huntington's disease (seven patients), and other extrapyramidal diseases (11 patients), and in five controls. Influx consisted of two components with low affinity and high exchange capacity. In individual subjects, the L-DOPA concentration giving half-maximal influx (Km) varied between 0.04 and 2.19 mM, and the maximum velocity (Vmax) of the saturable transport component was between 20 and 578 mumol/l cell water/h, which is compatible with the neutral amino acids of low affinity for the transport system. The range of Kd (the first-order rate constant for the unsaturable component) was between 0.11 and 0.36 hour-1. There was no gross deficit of the L-DOPA uptake process in patients with Parkinson's disease, Huntington's disease, dystonia, or other extrapyramidal diseases.
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PMID:Normal erythrocyte uptake of L-DOPA in Parkinson's, Huntington's, and related diseases. 622 Dec 1

The activity of the sympathoadrenal system (SAS) was studied in 132 patients with central nervous system diseases such as parkinsonism, deforming muscular dystonia (DMD), Huntington's chorea, myopathy and asthenic neurosis. The estimation was based on determinations of urine catecholamine (CA) excretion with the help of the fluorometric method developed by E. Sh. Matlina et. al. (1965). The control group included 50 healthy subjects. The findings obtained confirmed the reported data concerning the role of CA in the pathogenesis of the studied forms of nervous pathology. The study showed a decrease in dopamine excretion (DA) in parkinsonism, its increase in Huntington's chorea and DMD, and insufficiency of SAS activity in myopathy. Furthermore, additional criteria pointing to alterations in the diurnal SAS activity in the patients were revealed. These changes manifested themselves in the disruption of the diurnal rhythm of CA excretion as well as in the deficiency of DOPA and DA synthesis and deposition following a single dose of L-DOPA and nacome.
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PMID:[Circadian rhythm of catecholamine excretion, effect of L-DOPA and Nacom in various diseases of the nervous system]. 622 55


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