Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The clinical, biochemical, and pharmacologic responses to L-dopa were studied in 87 patients with Parkinson's disease. Eleven of the 87 patients had a long-duration response, 39 had a short-duration response, and 37 had a combination of both. Thirty-four of the 39 patients with short-duration response to L-dopa experienced a consistent and reproducible sequence of clinical and biochemical events after each dose, characterized by improvement of parkinsonism and a single phase of dystonia occurring during or shortly after the peak of dopa concentration in plasma and during maximal clinical improvement. We have called this the I-D-I- response, for Parkinsonism-Improvement-Dystonia-Improvement-Parkinsonism. The remaining five patients all had the onset of the disease at an unusually young age and showed a distinctly different response pattern consisting of a first phase of dystonia, before there was any improvement, followed by a phase of improvement without dystonia and then by a second phase of dystonia before the abrupt return of parkinsonism. We have called this the D-I-D response, for Parkinsonism-Dystonia-Improvement-Dystonia-Parkinsonsim. Dystonia occurs in the D-I-D- response when the concentration of dopa in plasma passes through a critical but relatively low level, whereas it remains absent as long as the concentration of dopa remains above that level. In the I-D-I- response, dystonia is avoided by keeping the plasma concentration of dopa low, in the D-I-D- response by keeping it high. It is postulated that in the D-I-D response postsynaptic depolarization blockade due to supramaximal stimulation of the neuronal system mediating dystonia occurs, whereas in the I-D-I response the postsynaptic members of the same neuronal population respond with excitation but not with depolarization blockade.
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PMID:Patterns of dystonia ("I-D-I" and "D-I-D-") in response to l-dopa therapy for Parkinson's disease. 83 64

Dystonia refers to involuntary, prolonged muscle contractions leading to sustained, often twisting, postures. High dose anticholinergic therapy for childhood onset dystonia, botulinum toxin injections for focal dystonia, and levodopa for diurnal dystonia provide symptomatic relief for some patients. Despite this, treatment of both idiopathic and secondary dystonia remains inadequate for many patients. Baclofen, a pre-synaptic acting GABA agonist, has been reported to benefit dystonia in a number of retrospective studies. Dramatic improvement in symptoms, especially in gait, was found in almost 30% of 31 children and adolescents with idiopathic dystonia in one retrospective study using doses ranging from 40 to 180 mg daily. The response to baclofen of adults with focal dystonia is less dramatic. One series of 60 adults with cranial dystonia found sustained benefit in 18%. Smaller series have not consistently found significant benefit in adults. Baclofen has been used to treat several secondary dystonias: tardive dystonia has occasionally been reported to improve and there are isolated reports of improvement in dystonia occurring in Parkinson's disease and in glutaric aciduria.
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PMID:Baclofen in the treatment of dystonia. 151 73

We examined whether the N-methyl-D-aspartate antagonist MK-801 (dizocilpine) would reverse parkinsonism or potentiate the effects of L-dopa in primates treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). In contrast to its effect in rodent models, treatment with MK-801 (0.1 mg/kg) caused bradykinesia and ataxia in parkinsonian primates, but no locomotor stimulation. Coadministration of MK-801 (0.1 mg/kg) with L-dopa (20 mg/kg) induced marked dystonia accompanied by bradykinesia and ataxia. Dystonia was not induced by either treatment given alone. These findings indicate that MK-801 should not be advocated as an adjunct to dopamine agonist therapy in Parkinson's disease.
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PMID:Dystonia induced by combined treatment with L-dopa and MK-801 in parkinsonian monkeys. 164 62

We report the clinical spectrum of 3 patients with Parkinson's disease who experienced complex patterns of levodopa-related dystonia. Dystonia was unrelieved by multiple medication regimens but responded well to continuous, duodenal levodopa infusions. Patients were able to remain mobile without severe dystonia despite a very narrow window of benefit between the levodopa concentration necessary to achieve the "on" state and that which caused the onset of dystonic spasms.
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PMID:Continuous levodopa infusions to treat complex dystonia in Parkinson's disease. 247 82

We studied the features of dystonia in 9 patients with untreated idiopathic Parkinson's disease and in 56 patients on sustained treatment with L-dopa. Dystonia was seen as an initial symptom in patients with both early- and late-onset Parkinson's disease and included action dystonia of the limbs and cranial dystonia. Although the coexistence of parkinsonism and dystonia suggests a common pathophysiology, antiparkinsonian drugs did not consistently influence dystonic spasms. L-dopa-induced dystonia was seen as an off-period, biphasic, or peak-dose phenomenon. Each type showed a distinctive pattern of localization of dystonic spasms, possibly reflecting neurochemical aspects of basal ganglia somatotopy. Neuropharmacological studies performed in 12 patients suggest that off-period dystonia is genuinely induced by L-dopa and best relieved by antiparkinsonian agents.
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PMID:Dystonia in Parkinson's disease: clinical and pharmacological features. 334 68

We studied various forms of dystonia associated with Parkinson's disease (PD) in 207 patients who were on levodopa therapy for more than 1 year. Dystonia, sometimes more than one type, occurred in 63 (30%). In five patients, dystonia preceded initiation of treatment. Fifteen patients had peak-dose dystonia, 33 had early-morning dystonia, and 20 had "off-period" dystonia. The different clinical features of the dystonias are presented and compared. Findings indicate that dystonia is a frequent feature of levodopa-treated PD patients.
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PMID:Forms of dystonia in patients with Parkinson's disease. 358 17

The "off" painful dystonia (OPD), usually concerning the feet, is a type of abnormal involuntary movement, induced by the chronic use of levodopa. It is mostly observed in the advanced stage of Parkinson's disease (PD), particularly in the early morning, in the evening, and late at night. Indeed, some patients have experienced OPD also during "on" periods when dystonic posture of the foot alternates with dyskinesia. The pain probably is due to sustained muscle contraction, which causes prolonged muscle spasm, as in primary dystonia or torticollis. Dopaminergic drugs like bromocriptine, pergolide, and especially apomorphine (s.c. infusions, or bolus), can dramatically improve the OPD. Anticholinergics baclofen and lithium are alos used in the management of OPD with some benefit. On the other hand, clinical experience shows that in many cases, these therapeutic procedures are not always enough to produce the expected results. Thirty PD patients (22 men and eight women) with OPD of the foot were treated with botulinum toxin (Botox, Btx) using electromyograms to guide injections. Dystonia was evaluated using a quantitative rating scale. The selection of the muscles for Btx treatment was carried out on the basis of foot posture. We injected Btx into tibialis posterior, tibialis anterior, gastrocnemius, flexor digitorum longus, and extensores hallucis longus with a median dose 40 IU for each muscle, distributed in two sites. In all patients, the pain improved within 10 days, whereas in 21 patients, the pain disappeared completely for 4 months (range, 3-7 months); a concomitant improvement in intensity of the dystonic spasm was also observed. No side effects were reported. Seven patients with associated "on" foot dystonia described an improvement of foot posture on walking. In conclusion, in this uncontrolled study, the use of Btx in OPD seemed a promising tool to improve pain linked to foot dystonia; however, because of the well-known underlying dopaminergic defect in OPD, the Btx therapy should be considered only if the dopaminergic treatment established for the management of OPD has failed.
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PMID:"Off" painful dystonia in Parkinson's disease treated with botulinum toxin. 765 52

Twenty index patients with hereditary essential tremor and their kindreds were studied to define the phenotype of this condition. Ninety-three first degree and 38 more distant relatives were examined; 53 definite and 18 possible secondary cases were identified. The age of tremor onset was bimodally distributed with a median at approximately 15 years. Segregation analysis indicated autosomal dominant inheritance and penetrance was virtually complete by the age of 65 years. There were no examples of the disease skipping a generation. Men and women were affected in equal proportions. About 50% of cases were alcohol responsive. In the majority of families alcohol responsiveness was either consistently present or did not occur, but in 20% of kindreds definite heterogeneity of responsiveness was encountered within each family. The typical phenotype was a mild symmetrical postural tremor of the upper limbs. Tremor of the legs, head, facial muscles, voice, jaw and tongue occurred but never in isolation and rest, task specific (e.g. primary writing tremor) and primary orthostatic tremors were not found. Head tremor was invariably mild and 75% was of a 'no-no' type. Dystonia (e.g. torticollis and writer's cramp) were not encountered, a finding which strongly suggests that many previous studies of 'essential tremor' were contaminated by cases of idiopathic or hereditary torsion dystonia. No association with Parkinson's disease was found but classical migraine occurred in approximately 26% of cases and co-segregated with tremor. The severity of arm tremor (assessed using a clinical rating scale and by scoring tremor in Archimedes spirals) and disability increased with advancing age and increasing tremor duration, but there was no correlation between age at tremor onset and either tremor severity or disability. Men and women were affected with equal severity. The sex of the affected parent had no influence on the severity of tremor or the degree of disability experienced by an affected child. Disability commenced in the second decade and progressively increased. All the index patients and 59% of the definite secondary cases had tremor induced disabilities. Eighty-five percent of index patients and 38% of secondary cases also reported some degree of social handicap. Twenty-five percent of index patients and 12% of secondary cases had been compelled to change jobs or retire. Biological fitness was normal.
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PMID:A study of hereditary essential tremor. 792 67

Movement disorders have been coined for diseases characterized by excessive and abnormal movements occurring in a conscious patient. Movement disorders are frequent among neurologic and psychiatric patients. They have a behavioral, or psychiatric, component. Movement disorders are mostly associated with disordered function in the basal ganglia, brain stem, and cerebellum. Such diseases are characterized by the occurrence of involuntary movement. This paper describes general concept of movement disorder, and shows classification by WHO (1991) and by Joseph, AB. and Young, RR. (1992). The classification of WHO includes I. Extrapyramidal movement disorders: 1) Parkinson disease, 2) Secondary parkinsonism, 3) Other degenerative diseases of the basal ganglia, 4) Dystonia, and 5) Other extrapyramidal and movement disorders. II. Behavioral and emotional disorders with onset usually occurring in childhood and adolescence: 1) Hyperkinetic disorders, 2) Tic disorders, and 3) others.
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PMID:[Movement disorders--concept and grand classification]. 827 55

Dystonia is a persistent attitude or posture in one or other of the extremes of athetoid movement. It may take the form of an over-extension or over-flexion of the hand, torsion of the spine, with arching and twisting of the back or forceful closure of the eyes and a fixed grimace. Dystonia is classified into idiopathic and symptomatic dystonia. Idiopathic dystonia is further divided into generalized, focal and segmental dystonia. Generalized dystonia covers classical torsion dystonia, paradoxical dystonia, myoclonic dystonia, dystonia with diurnal variation and Dopa-responsive dystonia. Dystonic tic, paroxysmal dystonia and hypnotic dystonia show a dystonic posture, although they are also accompanied by various other involuntary movements such as athetosis or chorea. Torticollis, writer's cramp or blepharospasm is assigned to the focal dystonia and Meige syndrome to the segmental dystonia. Symptomatic dystonia is observed in various neurological disorders, including cerebrovascular diseases, Parkinson's disease and Wilson's disease.
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PMID:[Dystonia]. 827 58


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