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)

Four women with Parkinson's disease undergoing prolonged levodopa therapy had daily episodes of dystonic posturing, affecting one lower extremity, several years after initiation of treatment. The dystonia occurred only in the early morning, on awakening and before the first dose of levodopa, when the patients were in the akinetic-rigid state with no dyskinesias. It further interfered with gait, slowly subsided within one to two hours, and did not recur until next morning. This abnormal involuntary posture was unaffected by manipulations of daily levodopa dosage and schedule, completely disappeared after withdrawal of drug therapy, and recurred following its readministration. Additional adverse reactions including dyskinesias, "on-off" phenomena, and declining efficacy of levodopa were present in all patients. Early-morning dystonia may represent another late side effect secondary to long-term levodopa administration in parkinsonism.
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PMID:Early-morning dystonia. A late side effect of long-term levodopa therapy in Parkinson's disease. 44

Tiapride, a substituted benzamide derivative closely related to metoclopramide, reduced levodopa-induced peak dose involuntary movements in 16 patients with idiopathic Parkinson's disease. However, an unacceptable increase in disability from Parkinsonism with aggravation of end-of-dose akinesia led to its cessation in 14 patients. Tiapride had no effect on levodopa-induced early morning of "off-period" segmental dystonia. These results fail to support the notion that levodopa-induced dyskinesias are caused by overstimulation of a separate group of dopamine receptors.
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PMID:Tiapride in levodopa-induced involuntary movements. 45 86

Ventricular fluid concentrations of homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA), the respective metabolites of dopamine and serotonin, were measured in 57 patients undergoing thalamotomy for relief of movement disorders. The diseases included were Parkinson disease, dystonia, cerebral palsy, multiple sclerosis, and posttraumatic or posthypoxic encephalopathy. Untreated parkinsonian patients had the lowest mean HVA level (119 ng per milliliter). Patients with multiple sclerosis or with posttraumatic or posthypoxic encephalopathy with both intellectual impairment and bilateral motor involvement had lower mean HVA levels (197 and 177 ng per milliliter, respectively) than cerebral palsy patients with bilateral motor disease (233 ng per milliliter), dystonia patients (246 ng per milliliter), or multiple sclerosis patients with normal intellect (376 ng per milliliter). The data suggest that diffuse cerebral disease may lead to diminished dopaminergic activity. Ventricular fluid 5-HIAA levels were similar in all groups of patients. Chronic cerebellar stimulation markedly increased ventricular fluid HVA and 5-HIAA levels, indicating that cerebellar stimulation affected cerebral dopaminergic and serotonergic systems.
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PMID:Ventricular fluid homovanillic acid and 5-hydroxyindoleacetic acid concentrations in patients with movement disorders. 56 83

In this chapter, we have attempted to demonstrate that chronic manganese intoxication, in both animals and man, is a better model of dystonia than of Parkinson's disease. It is proposed that many of the monoamine and endocrine changes in dystonia may be the result of disturbances in manganese metabolism. A search for such modifications in human dystonia victims is presently underway. Preliminary studies indicate that head and pubic hair manganese concentrations are elevated in dystonia patients.
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PMID:Role of manganese in dystonia. 82 21

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

The occurence of extranuchal dystonia, facial spasm, parkinsonian symptoms (facial masking, bradykinesia, rigidity), tremor and family history of tremor was tabulated in a group of 30 patients with IST. The incidence of extranuchal dystonia increased as severity of IST increased. There was a strong trend for severity of extranuchal dystonia to increase as severity of torticollis increased, which was significant (p less than 0.001). There was a similar trend for severity of facial spasm to increase with increasing severity of torticollis (p less than 0.025). Parkinsonian features were seen in 10 of 30 patients, and in three the diagnosis of Parkinson's disease could be entertained. Tremor was seen in 26 of 30 patients being mild in 12, moderate in 11, and severe in three. A family history of tremor was present in 16 of 28 cases for whom history was available (12 primary, four secondary relations). The results are most consistent with the hypothesis that IST is a variant of DMD with tremor as an integral part of the disease and tremor represents a forme of the disease in family members.
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PMID:Dystonia and tremor in spasmodic torticollis. 94 73

We report a sporadic case of Dopa responsive dystonia and two families with different combinations of parkinsonism and dystonia. The possible relationships between Dopa responsive dystonia and early onset Parkinson's disease are discussed.
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PMID:Dopa responsive dystonia and juvenile Parkinson's disease: two subtypes of the same disorder? 129 88

We investigated digastric reflex excitability in normals and in patients with extrapyramidal disorders such as primary cranial dystonias and Parkinson's disease. Relationships between exteroceptive suppression of masseter muscle and digastric reflex were also investigated in some cases. Digastric reflex hyperexcitability was observed in dystonic patients when compared to normals and parkinsonian patients. Furthermore, some patients with cranial dystonia presented absence of exteroceptive suppression reflex in masseter muscle with enlarged digastric response. These results indicate hyperexcitability of the digastric reflex and abnormal agonist-antagonist muscle co-contraction in chewing reflexes of patients with cranial dystonias. This shows that digastric reflex is an important electrophysiological investigation to explore the physiopathological mechanisms of primary cranial dystonias.
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PMID:Electrophysiological study on jaw-opening reflex recorded from digastric muscle in Parkinson's disease and primary cranial dystonias. 129 25

Dopa-sensitive dystonia has been recognised for twenty years. It may occur in the first years of life. It first affects the lower limbs, then generalized becomes, as in torsion dystonia. Eight clinical cases are presented in five boys and three girls. The absence of the disorder in the parents, but its presence in siblings in three cases suggests that it might be recessively inherited. The symptoms are severe enough to cause major functional disability. In some cases, the intensity of the motor disorder varies during the days being, less pronounced in the morning or after a nap and more marked in the evening. Nonetheless, this feature is not constant and thus cannot be considered as an essential diagnostic criterion. Treatment with levodopa gives remarkable and durable results, but it must be continued indefinitely. Abnormal movements accompany an overdose but regress when the dosage is decreased. Unlike Parkinson's disease, it is not necessary to increase or fragment doses to avoid fluctuations in the efficacy of treatment during the day. On the contrary, after several years of the illness a decrease in daily dosage sometimes to a single dose is possible. Discontinuing treatment leads to reappearance of dystonia after two or three days. There are no established biological criteria to aid diagnosis. However, a decrease in urine levels of homovanillic acid was observed in two cases. Dopa-sensitive dystonia should be regarded as distinct from juvenile Parkinson's disease, firstly because of its symptomatology and secondly, and more importantly, because of its particular course, since fluctuations in therapeutic efficacy are never observed. It is the only known example of dopaminergic insufficiency that is chronically almost completely controlled by a modest exogenous supply of levodopa.
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PMID:[Dopa-sensitive dystonia]. 130 57

Animal data indicate that serotonin (5-HT) is a major neurotransmitter involved in the control of numerous central nervous system functions including mood, aggression, pain, anxiety, sleep, memory, eating behavior, addictive behavior, temperature control, endocrine regulation, and motor behavior. Moreover, there is evidence that abnormalities of 5-HT functions are related to the pathophysiology of diverse neurological conditions including Parkinson's disease, tardive dyskinesia, akathisia, dystonia, Huntington's disease, familial tremor, restless legs syndrome, myoclonus, Gilles de la Tourette's syndrome, multiple sclerosis, sleep disorders, and dementia. The psychiatric disorders of schizophrenia, mania, depression, aggressive and self-injurious behavior, obsessive compulsive disorder, seasonal affective disorder, substance abuse, hypersexuality, anxiety disorders, bulimia, childhood hyperactivity, and behavioral disorders in geriatric patients have been linked to impaired central 5-HT functions. Tryptophan, the natural amino acid precursor in 5-HT biosynthesis, increases 5-HT synthesis in the brain and, therefore, may stimulate 5-HT release and function. Since it is a natural constituent of the diet, tryptophan should have low toxicity and produce few side effects. Based on these advantages, dietary tryptophan supplementation has been used in the management of neuropsychiatric disorders with variable success. This review summarizes current clinical use of tryptophan supplementation in neuropsychiatric disorders.
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PMID:L-tryptophan in neuropsychiatric disorders: a review. 130 30


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