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

We report on 4 boys (3 in one family) who have a remarkably constant syndrome of childhood-onset choreoathetosis with later spasticity, postnatal microcephaly, growth and mental retardation, apparent external ophthalmoplegia and varying degrees of deafness. The pedigrees are consistent with X-linked inheritance. The syndrome is compared and contrasted with others comprising basal ganglion dysfunction in childhood. It is concluded that clinically and genetically the condition is unique.
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PMID:A new X-linked syndrome comprising progressive basal ganglion dysfunction, mental and growth retardation, external ophthalmoplegia, postnatal microcephaly and deafness. 653 52

This study presents the results of neurological assessments of a representative sample of seven-year-old Swedish children with perceptual, motor and attentional deficits and their controls (N = 141). Among those children diagnosed as suffering from minimal brain dysfunction (MBD), the majority showed neurodevelopmental deviations indicative of the "clumsy child syndrome'. However, 20 per cent had slight signs of choreoathetosis, diparesis, hemiparesis or ataxia. Other associated neurodevelopmental deviations are considered. The correlation between neurological findings and background factors is discussed: the MBD group had higher scores for various "organic' background factors than the comparison children, and the children with neurological syndromes had somewhat higher scores than the remaining children with MBD. The difficulties in distinguishing MBD from mental retardation, cerebral palsy and childhood psychoses is clearly illustrated. Long-term follow-up will indicate the prognostic significance of these findings.
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PMID:Perceptual, motor and attentional deficits in seven-year-old children: neurological and neurodevelopmental aspects. 687 93

Lesch-Nyhan Syndrome (LNS) is a biochemical disorder characterized by a virtually complete deficiency of an enzyme of purine metabolism, hypoxanthineguanine phosphoribosyltransferase. This sex-linked recessive inborn error of metabolism is characterized clinically by: hyperuricaemia, excessive production of uric acid, certain characteristic neurological features including self-mutilation, choreoathetosis, spasticity and mental retardation. This paper will review the clinical, biochemical and genetic features of Lesch-Nyhan Syndrome and report a case in which repeated lip chewing resulted in destruction of the lower lip and the need for surgical intervention.
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PMID:Lesch-Nyhan syndrome: surgical treatment in a case with lip chewing. A case report. 693 76

Eighty infants with cerebral palsy including monoplegia, diplegia, quadriplegia, hemiplegia, choreoathetosis, hypotonia with mental retardation and cerebellar ataxia, underwent Computed Cranial Tomography (CCT). Specific morphological anomalies such as ventricular dilatation with or without diverticulum, cortical atrophy, low density areas and calcifications, occur with varying frequency in each clinical groups. There exists a good correlation between the pathogenesis of the lesions, clinical data and CCT pictures.
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PMID:Cranial computerized tomography in cerebral palsy. An attempt at anatomo-clinical and radiological correlations. 720 4

Lesch-Nyhan syndrome is a rare X-linked disease characterized by over-production of uric acid and a central nervous system (CNS) disorder consisting of mental retardation, spasticity, choreoathetosis, and a compulsive form of self-mutilation. A deficiency in hypoxanthine-guanine phosphoribosyl transferase (HPRT) provides the underlying metabolic basis for this disease. A 12 month-old male baby who had orange crystals over the diapers since he was 3 months old was brought to our hospital due to developmental delay. Mental retardation and athetosis were also noted. Chemical analysis revealed hyperuricemia (uric acid 8.6 mg/dl). Urine routine showed microscopic hematuria and uric acid crystals. The activity of HPRT in erythrocyte lysates of parents were both within normal limits, but that of the patient was very low (0.0547 nm/min/mg protein, < 0.05% of control). His younger brother was born 2 months after this disorder diagnosed in this patient. The younger brother was noted to have uric acid crystals over the diapers when he was 40 days old and hyperuricemia (10.6 mg/dl) showed up later. He was also a case of Lesch-Nyhan syndrome since the activity of HPRT in erythrocyte lysates was also low (0.0327 nmol/min/mg protein, < 0.05% of control). Further studies, including carrier detection and deoxyribonucleic acid (DNA) analysis, could be helpful for genetic counseling. This syndrome is rare among Chinese, and this may be due to underdiagnosis.
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PMID:Lesch-Nyhan Syndrome: report on two brothers. 783 90

The term of dentatorubral and Pallidoluysian atrophy (DRPLA) was first introduced by Smith, who proposed that there was a combination of cerebellar ataxia with choreoathetosis based on DRPL lesions. In 1972, Naito et al. reported two families with progressive myoclonus epilepsy (PME) syndrome with cerebellar ataxia, and hyperactive deep tendon reflexes. In 1977, Oyanagi et al. reported 4 autopsied cases of PME, and pointed out degenerative lesions in the DRPL systems. In 1982, Naito and Oyanagi reported this type of PME to be hereditary DRPLA, with a clinicopathological disease entity. This type of PME with DRPLA has been made a major category, especially in Japan. In this article, clinicopathological features of the hereditary DRPLA will be reviewed on the basis of 45 patients with this disease. The disease was inherited as an autosomal dominant fashion, and induces a wide rage of clinical features depending upon the age of onset, ranging from 3 years to 69 years of age. The initial symptoms were variable according to the age of onset and mental retardation was the most prominent symptom in the patients in which the disease started in the first decade and with an epileptic seizure in the second decade. In the following next two decades, the incidence of epileptic seizure, as initial symptoms was decreased to 23% and gait disturbance and ataxia in 38% of the patients, which increased to 73% in the 5th and 6th decades. The cardinal symptoms of hereditary DRPLA includes mental retardation, epileptic seizure and myoclonus, cerebellar ataxia with gait disturbances, psychological symptoms including clonus, cerebellar ataxia with gait disturbances, psychological symptoms including character changes, and dementia.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Hereditary dentatorubro-pallidoluysian atrophy (DRPLA): clinical studies on 45 cases]. 827 85

Two sisters were presented, 16 years old and 12 years old, who showed similar clinical courses. They had had mental retardation since early childhood, and then ataxia began. They suffered from astatic and tonic seizures from early school age, which gradually evolved to intractable epilepsies. Spasticity progressed, and they deteriorated both physically and mentally. They revealed photo-sensitivity; convulsions were induced by the flickering of light. They were attacked by myoclonic seizures as well as choreoathetosis, and became bedridden by the latter part of the elementary school age. There were no fruitful results of any kind from the laboratory examinations for metabolic disorders. EEG showed that the epileptic seizure discharges were induced by photic stimulation; there were frequent 3-4 Hz diffuse spike-and-wave short bursts during waking and sleep periods. MRI findings of the elder sister at the age of 16 revealed remarkable diffuse brain atrophy. Gene analysis showed abnormally enlarged DNA fragments localized on the short arm of chromosome 12. This meant expanded CAG trinucleotide repeats. The younger sister died at the age of 12 years. Autopsy findings revealed degeneration of both dentatorubral and pallidoluysian pathways. There were especially remarkable gliosis and neuronal cell loss in the outer segment of globus pallidus, and moderate neuronal cell loss and typical grumose degeneration in the dentate nucleus. The diagnosis of juvenile-type hereditary dentatorubral-pallidoluysian atrophy was compatible with the pathologic findings. This diagnosis will be made possible before death through the understanding of the clinical symptoms and molecular genetics.
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PMID:[Sisters with early onset hereditary dentatorubral-pallidoluysian atrophy of childhood--DNA analysis and clinicopathological findings]. 853 13

The clinical, genetic, and neuroradiologic characteristics of dentatorubral-pallidoluysian atrophy (DRPLA) are delineated in six patients from three generations of a Japanese family. The clinical characteristics of the disease varied, the age at onset depending on patients with juvenile-onset were characterized by myoclonus, epilepsy, and mental retardation whereas cerebellar ataxia, choreoathetosis, and dementia were typical of adult- and senile-onset patients. All affected individuals showed one expanded allele with the repeat number of CAG at the DRPLA locus, ranging from 58 to 82, and a normal allele, ranging from 10 to 21. The most severely affected patient, a case of maternal transmission and with the largest allele, became bedridden in a vegetative state by age 12. On the CT and MRI, varying degrees of brain atrophy were present in all patients. T2-weighted MRI in patients with senile-onset showed symmetric high-signal lesions in the cerebral white matter, globus pallidus, thalamus, midbrain, and pons. However, MRI in younger patients revealed no such lesions and CT failed to demonstrate lesions in the globus pallidus and brain stem. Thus, intrafamilial heterogeneity of DRPLA was also evident on MRI. High-signal lesions involving both, subcortical white matter and thalamus may be characteristics of senile-onset patients and may correlate with their dementia.
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PMID:Dentatorubral-pallidoluysian atrophy (DRPLA): clinical, genetic, and neuroradiologic studies in a family. 858 78

The Lesch-Nyhan syndrome results from a complete or virtually complete deficiency of the purine salvage enzyme, hypoxanthine guanine phosphoribosyl transferase (HPRT). The disease is characterized by hyperuricemia, choreoathetosis, spasticity, compulsive self-mutilation, and mental retardation. Patients with a partial deficiency of HPRT are spared most of the neurological disorder of Lesch-Nyhan syndrome. The specific relationship between HPRT deficiency and the neurological dysfunction in the Lesch-Nyhan syndrome is not known, at present. The genetic lesion which result in HPRT deficiency are heterogeneous. About 90 different mutations were found in over 110 families. The DNA-based mutation detection technique can be used for the diagnosis of affected males and for the determination of carrier status of asymptomatic females. This technique is also applicable for the prenatal diagnosis for Lesch-Nyhan syndrome. Transgenic mice, deficient in HPRT activity, have been obtained but they do not show any neurological dysfunction. After administration of 9-ethyladenine, however, they showed the self-injury behavior.
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PMID:[Complete and partial deficiency of HPRT]. 897 12

Lesch-Nyhan syndrome is a hereditary disorder of purine metabolism causing overproduction of uric acid and neurological problems including spasticity, choreoathetosis, mental retardation, and compulsive self-mutilation. The syndrome is caused by a defect in the enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT), which converts guanine and hypoxanthine to the nucleotides GMP and IMP. There is evidence that the neurological problems are due to an adverse effect of the HPRT deficiency on the survival and/or development of dopaminergic neurons, specifically. Here we report that HPRT-deficient PC12 mutants that have a normal or near normal dopamine content (55-97% of that of wild-type cells) fail to undergo neuronal differentiation induced by nerve growth factor (NGF) when the de novo pathway of purine synthesis is partially inhibited. However, nerve growth factor-induced differentiation is near normal under these conditions in PC12 HPRT-deficient mutants containing much lower dopamine levels (<8% of that of wild type cells), indicating a neurotoxic effect of the endogenous dopamine in the mutants. The degree of inhibition of the de novo pathway of purine synthesis was the same in both classes of HPRT-deficient mutants. Expression of BCl-2 in a PC12 mutant that has a normal dopamine content allowed partial NGF-induced differentiation suggesting that the apoptotic pathway might be involved in the failure of differentiation when the de novo pathway of purine synthesis is partially inhibited.
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PMID:Impaired differentiation of HPRT-deficient dopaminergic neurons: a possible mechanism underlying neuronal dysfunction in Lesch-Nyhan syndrome. 967 Sep 94


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