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)

In galactosemia, prevention of mental retardation depends on early recognition of the disorder and institution of dietary restriction of galactose. We describe an automated fluorometric micromethod for galactose in whole blood spotted on filter paper. Galactose is oxidized by galactose oxidase to D-galacto-hexadialdose and H2O2 and measured as the highly fluorescent condensation product of homovanillic acid formed when H2O2 is acted upon by horseradish peroxidase. The procedure is 10-fold more sensitive than colorimetric procedures for galactose and is not hampered by the nonspecific fluorescence from endogenous NADPH that is encountered in methods in which galactose dehydrogenase is used. At a sampling rate of 40/h with a sample-to-wash ratio of 1/2, carryover is negligible, reproducibility is excellent, and 80% of steady state is achieved. Analytical recovery of added galactose was 95%. The method has the requisite sensitivity and accuracy for quantification of galactosemia and galactosuria in milkfed newborn infants and genetic evaluation of families of patients.
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PMID:Automated fluorometric analysis of galactose in blood. 87 Feb 60

The authors performed galactose loading tests in children suffering from chronic diseases: recurrent bronchitis vomiting, diarrhoea, milk-intolerance, somatic and mental retardation, cramps. In 32 of the 92 examined cases galactose levels rose until pathological, pseudo- diabetic levels. Stillbirth, cataract, hyperbilirubinaemia, convulsions occurred among family members of 10 patients. Galactose-1-phosphat-uridyl-transferase levels were decreased only in 4 of the 17 patients examined. In the other cases some different pathway of galactose metabolism is suspected. Complete remission of symptoms was achieved with diet devoid of milk sugar (lactose) in 29 patients: one infant died and two others remained mentally retarded. According to the examinations presented minor deviations of galactose metabolism cause clinical symptoms more frequently in early life as it was supposed until now.
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PMID:[Galactose loading test in infants and small children suffering in recurrent bronchitis and other chronic illness (author's transl)]. 611 85

Galactosemia is an autosomal recessive, inborn error of galactose metabolism due to the deficiency of galactose-I-phosphate uridyl transferase. Late-onset neurologic complications may develop despite Galactose restriction. Three adult patients are reported. They suffered from mental retardation. Two of them developed progressive cerebellar ataxia, spastic gait and postural tremor. The magnetic resonance imaging revealed moderate cortical atrophy, multifocal areas of increased signal in the periventricular white matter on T2-weighted images, and in one case, abnormal myelination. The Fluoro-2-deoxy-D-glucose position emission tomography showed different patterns of regional hypometabolism.
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PMID:[Late neurologic complications of galactosemia: study of 3 cases]. 767 42

Classical galactosemia, which is caused by deficiency of galactose-1-phosphate uridyltransferase, is characterized by acute problems of hepatocellular dysfunction, sepsis, cataracts and failure to thrive. Galactose limitation reverses these symptoms immediately; however, the long-term complications, such as mental retardation and ovarian failures are major problems in most of these patients. In order to investigate the molecular basis for phenotype variation in galactosemia, we have screened the most common mutation in the GALT gene, Q188R. We have further examined those patients who are heterozygous for Q188R or negative for this mutation by SSCP analysis and direct sequencing. In three male patients, we have identified, for the first time, two stop-codon mutations in the GALT gene, G212X (exon 7) and E340X (exon 10). Two patients of 8 and 28 years of age, respectively, who are compound heterozygotes for Q188R and G212X, have severe mental retardation and their general clinical condition is more severe than that of patients with missense mutations. The third patient, who is 8 years of age and who is homozygous for E340X, the N314D polymorphism and a silent substitution L218L, presents with a relatively normal physical and mental condition to date.
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PMID:Characterization of two stop codon mutations in the galactose-1-phosphate uridyltransferase gene of three male galactosemic patients with severe clinical manifestation. 852 34

Classical galactosemia is an inherited metabolic disease that results from galactose-1-phosphate uridyltransferase deficiency. Untreated galactosemia has various manifestations, including central nervous system damage, hepatic failure, cataract. Galactose-restricted dietary treatment, the only therapy used in galactosemia, brings considerable improvement, especially in the neonatal period. However, in the most galactosemic patients this treatment does not prevent development of late-onset complications; mental retardation, ovarian failure and neurologic disturbances. This article presents a review of contemporary hypotheses on possible factors influencing the outcome in galactosemia, especially in regard to late-onset complications.
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PMID:[Galactosemia: a problem still unsolved]. 875 65

Classical galactosemia, characterized clinically by acute hepatic dysfunction, sepsis, cataract, and failure to thrive, is caused by deficiency of galactose-1-phosphate uridyltransferase (GALT). Galactose restriction normalizes these acute symptoms; however, long-term complications such as intellectual deficits and ovarian failure are conspicuous in the majority of patients. Here we report two Turkish siblings with classical galactosemia. The clinical course of the two children differed markedly: only the older girl suffered from severe acute symptoms during the neonatal period, and she developed greater mental retardation than her younger affected brother. The functional activity of GALT was virtually absent in each affected children. The mother and two healthy siblings exhibited approximately 50% normal GALT activity and the father approximately 25%. Molecular analysis revealed that these two galactosemic siblings were homozygous for a stop codon mutation of E340X in GALT exon 10. Moreover, two additional mutations, a neutral polymorphism L218L and N314D, which are typical for the Duarte-I variant, were found in the same GALT allele. The two healthy siblings and the parents were heterozygous for these combinations of mutations. In addition, the father's second GALT allele revealed three intron mutations at nucleotide position 1105 (G-->C), 1323 (G-->A) and 1391 (G-->A) and the N314D mutation, which correspond to the mutations of Duarte-2 variant. Our findings indicate that in classical galactosemia several distinct mutations can be present in one allele (in cis) of the GALT gene. Therefore it seems to be necessary to examine all introns and exons of the GALT gene in galactosemic patients who do not carry the Q188R mutation or another frequent mutation in the GALT gene.
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PMID:Simultaneous occurrence of various mutations and polymorphisms in cis and in trans of the galactose-1-phosphate uridyltransferase gene in a Turkish family with classical galactosemia. 976 50

Galactose is a hexose essential for production of energy, which has a prebiotic role and is essential for galactosylation of endogenous and exogenous proteins, ceramides, myelin sheath metabolism and others. The inability to metabolize galactose results in galactosemia. Galactosemia is an autosomal recessive disorder that affects newborns who are born asymptomatic, apparently well and healthy, then develop serious morbidity and mortality upon consuming milk that contains galactose. Those with galactosemia have a deficiency of an enzyme: classic galactosemia (type 1) results from severe deficiency of galactose-1-uridylyltransferase, while galactosemia type II results from galactokinase deficiency and type III results from galactose epimerase deficiency. Many countries include neonatal screening for galactosemia in their national newborn screening program; however, others do not, as the condition is rather rare, with an incidence of 1:30,000-1:100,000, and screening may be seen as not cost-effective and logistically demanding. Early detection and intervention by restricting galactose is not curative but is very rewarding, as it prevents deaths, mental retardation, liver cell failure, renal tubular acidosis and neurological sequelae, and may lead to resolution of cataract formation. Hence, national newborn screening for galactosemia prevents serious potential life-long suffering, morbidity and mortality. Recent advances in communication and biotechnology promise facilitation of logistics of neonatal screening, including improved cost-effectiveness.
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PMID:Screening for galactosemia: is there a place for it? 3121 78