Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Similar movement disorders developed in two 8-year-old retarded children while they were receiving phenytoin. Seizures subsequent to a diphtheria-pertussis-tetanus immunization had developed in each child at 1 to 2 months of age. A static encephalopathy ensued, characterized by mental retardation, ataxia, spasticity, and a mixed seizure disorder. Intermittent dystonia and choreoathetosis developed insidiously while serum phenytoin concentrations were in the therapeutic range. Sustained dystonia and choreoatheosis developed 2 hours after an oral provocation with phenytoin. The baseline abnormalities on the electroencephalogram remained unchanged during the choreoathetosis. Recognizable metabolic abnormalities known to be associated with similar movement disorders were excluded. It was concluded from these studies that the movement disorder is secondary to phenytoin and can occur at therapeutic serum concentrations. Phenytoin is a central anticholinergic agent and a central stimulant of serotonin, and may induce movement disorders as a result of altering these neurotransmitters in the brain. The variable expression of these movement disorders may relate to the nature of the preexisting striatal insult.
 ...
PMID:Phenytoin-induced dystonia and choreoathetosis in two retarded epileptic children. 94 1

Glutaric aciduria is a disorcer of lysine, tryptophan, and hydroxylysine metabolism characterized by intermittent metabolic acidemia, dystonia, athetosis and mental retardation. It is due to a recessively inherited deficiency of glutaryl-CoA dehydrogeanse, the enzyme(s) which catalyze the dehydrogenation of glutaryl-CoA to glutaconyl-CoA and decarboxylation of the latter to crotonyl-CoA. Abnormal quantities of glutaric, beta-hydroxyglutaric, and glutaconic acids are found in the urine of these patients. The nature of the movement disorder prompted study of the effects of the abnormally excreted metabolites on brain glutamate decarboxylase, an enzyme implicated in the pathogenesis of Huntington's chorea. Glutamate decarboxylase activity was examined in rat and rabbit brain acetone powders, stabilized with pyridoxal phosphate and glutathione. Glutarate, beta-hydroxyglutarate, and glutaconate were competitive inhibitors of this emzyme, Ki values being 1.3 X 10(-3) mol/l, 2.5 X 10(-4) mol/l, respectively. This inhibition may explain the neurological accompaniments of this syndrome.
 ...
PMID:Inhibition of brain glutamate decarboxylase by glutarate, glutaconate, and beta-hydroxyglutarate: explanation of the symptoms in glutaric aciduria? 124 44

In a male infant with macrocephaly and dystonic cerebral palsy glutaric aciduria type I was detected by analysis of urine for organic acids. Glutaric aciduria type I is an inherited metabolic disorder of organic acids due to a defect of glutaryl-CoA-dehydrogenase in the intermediate metabolic step of lysine and tryptophan degradation. In the urine glutaric acid is usually accompanied by 3-hydroxy-glutaric acid in abnormal quantities. The enzyme defect in our patient was proved in cultured fibroblasts. In the cerebral computer tomography marked atrophy of bilateral frontotemporal regions could be demonstrated. The amount of urinary glutarat excretion decreased after protein but especially after lysine and tryptophan restriction in the diet. The administration of carnitine improved carnitine levels in blood and urine. Although the progression of neurological impairment could be stopped, dystonia and dyskinesis remained nearly unaltered. In spite of severe motor retardation, recognition and vocalisation were established. In the two year old patient mental retardation is relatively mild comparing with motor retardation. The administration of 100 or 200 mg Riboflavin/day was stopped, as it did not alter clinical symptoms or excretion of glutarat. Baclofen, an analogue of gamma-amino-butyric acid, was orally given (2 mg/kg/day) and improved dystonia, but did not influence organic aciduria. The neurological manifestations may be due in part to inhibition of neuronal glutamat decarboxylase by glutaric acid with decreased gamma-amino-butyric acid biosynthesis. The characteristic clinical symptoms with macrocephaly and dystonia and the very typical pattern of organic acids in urine are a challenge for rapid diagnosis and therapy.
 ...
PMID:[Macrocephaly and dystonic cerebral palsy in a child with type I glutaric aciduria]. 194 71

We studied 5 boys, 2 to 10 years old, with marked or complete deficiency of hypoxanthine-guanine phosphoribosyltransferase and Lesch-Nyhan syndrome with varying degrees of mental retardation, dysarthria, chorea, dystonia, spasticity, and ataxia. Four patients had marked reduction of homovanillic acid in the cerebrospinal fluid (CSF) and all showed low CSF 3-methoxy-4-hydroxy phenylethylene glycol, indicating reduced dopamine and norepinephrine turnover. Three patients showed high CSF 5-hydroxyindoleacetic acid, suggesting increased serotonin turnover. Some patients improved with carbidopa-levodopa, but others benefited from tetrabenazine, a monoamine-depleting agent. This study provides support for the theory of abnormal central monoamine metabolism in Lesch-Nyhan syndrome.
 ...
PMID:Lesch-Nyhan syndrome: a study of motor behavior and cerebrospinal fluid neurotransmitters. 245 72

A woman aged 21 with a variant form of metachromatic leucodystrophy (MLD) combined with another form of leucodystrophy is described. The clinical symptoms were retinitis pigmentosa and progressive neurological deficits such as mental retardation, dystonia, pyramidal tract involvement and peripheral neuropathy. The biochemical findings were marked deficiency of arylsulfatase-A and cerebroside-sulfatase in cultured fibroblasts and excretion of sulfatides in the urine. Sulfatide-loading of cultured fibroblasts showed almost normal uptake and degradation of sulfatides. The patient's sister suffers from a clinically similar neurological disease, but normal activity of arylsulfatase-A was found in her leucocytes. A severe oral-facial dystonia in the patient was successfully controlled by l-dopa.
 ...
PMID:A variant form of metachromatic leucodystrophy in a patient suffering from another congenital degenerative neurological disease. 285 48

We describe a family with a syndrome of mental retardation, dystonic movements of the hands and dysarthria inherited in an X-linked recessive pattern. DNA marker studies gave a maximum lod score of 2.11 at theta of 0.00 for DXS41 with a likely localization of the gene to Xpter----Xp21.
 ...
PMID:X-linked mental retardation with dystonic movements of the hands. 317 52

Tardive dystonia is a relatively uncommon long term complication of neuroleptic therapy. The prevalence of this syndrome is unknown. This study, of chronic hospitalised psychiatric patients, revealed a tardive dystonia prevalence of 1.5%. Risk factors in this small population appeared to be mental retardation and convulsive therapy.
 ...
PMID:Tardive dystonia in a psychiatric hospital. 361 60

This is the first reported case of dystonia with a partial deletion of the long arm (q) of chromosome 18. Neurologic findings in the 18q- syndrome include mental retardation, seizures, nystagmus, incoordination, tremor, and chorea. A 36-year-old woman with an 18q terminal deletion [karyotype 46,XX,del(18)(q22.2)] had hypothyroidism, diabetes mellitus, borderline intelligence, short stature, short neck, sensorineural hearing loss, and sensorimotor axonal neuropathy. Parents' karyotypes were normal. She had had incoordination and writing difficulty since childhood. Posturing and tremor of the head began at age 16, followed by arm tremors. She had jaw deviation and tremor, neck tremor with retrocollis, involuntary pronation of the right arm, coarse postural and severe action tremor, and tight pen grip with dystonic wrist extension on writing. The 18q- syndrome should be added to the list of genetic causes of secondary dystonia. A karyotype analysis should be considered in secondary dystonias, particularly when there are associated features such as short stature and endocrinopathies.
 ...
PMID:Dystonia in a patient with deletion of 18q. 756 32

A case, diagnosed as 18p-syndrome by typical clinical appearance and by chromosomal analysis, presented with multiple nervous system defects consisting of bilateral pyramidal tract signs, weakness and focal dystonia of the lower extremities, and concentric visual field defect. Chromosomal analysis revealed karyotype 46, X, dic (Y;18) (p11;p11), inv(9) (p11q13), and the points of chromosomal breakages were thought to be in the short arm of chromosome 18 and in the short arm of Y chromosome. 18p-syndrome is caused by a chromosomal deletion, and presents with a wide variety of clinical appearances. Many cases have been reported since the original descriptions by de Grouchy in 1963, though with few mentions of neurological deficits other than mental retardation. Furthermore, there have been no reports of pyramidal tract signs, weakness and focal dystonia of the lower extremities, or visual field defect, without recognizable anatomical abnormalities. Our case of 18p-syndrome is quite rare because of multiple nervous system abnormalities mentioned above, not accompanied by malformations of the central nervous system.
 ...
PMID:[18p-syndrome with bilateral pyramidal tract signs, dystonia of the lower extremities and concentric visual field defect]. 792 61

A family with a syndrome of mental retardation, dystonic movements of the hands, and dysarthria (MIM no. 309510) was described and mapped to Xp22 by Partington et al. (Am J Med Genet 1988; 30:251-262). The original localization encompassed the distal half of the short arm of the X chromosome, with a peak lod score of 2.1 at the DXS41 locus. The gene localization for this disorder (PRTS) has now been refined using recently characterized dinucleotide repeat markers. The PRTS gene maps between DXS365 and DXS28, an interval estimated to be less than 15 cM. A peak lod score of 3.01 at a recombination fraction of zero was generated by 2-point linkage analysis with the marker DXS989. Dystonic movements may be progressive and could be overlooked in children. Clinical assessments of affected men who are mentally retarded should be critically evaluated for this manifestation, where they belong to families in which the gene localization overlaps with PRTS.
 ...
PMID:X-linked mental retardation with dystonic movements of the hands (PRTS): revisited. 794 40


1 2 3 4 5 6 7 8 9 10 Next >>