Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.6.1 (sulfatase)
 3,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We describe nine patients with metachromatic leukodystrophy. Seven patients had the juvenile form; in two others, the age at onset was 1 year, but the clinical course was different from the late infantile form. The age at onset ranged from 1 to 18 years; the duration ranged from three to 17 years. Mental retardation associated with motor impairment and pathological EEG and electromyographic findings were the main clinical findings. In patients with early onset, mental retardation was almost the only symptom for the first ten years. Segmental demyelination, remyelination, onion bulb formation, and occasional perivascular macrophages containing metachromatic lipid were the main findings in sural nerves studied after biopsy. The mean arylsulfatase-A (ASA) activity was 1.3 nmoles of nitrocatechol sulfate per milligram of protein per 30 minutes in peripheral leukocytes of the patients, 62.0 in the heterozygotes, and 139.0 in the controls. The ASA band could not be detected in enzyme electrophoresis.
 ...
PMID:Juvenile metachromatic leukodystrophy. Clinical, biochemical, and neuropathologic studies in nine new cases. 610 4

Prenatal diagnosis was requested by a family at risk for metachromatic leukodystrophy (MLD). An examination of the family leukocyte arylsulfatase A profile revealed that the mother had pseudo arylsulfatase A deficiency. Cultured amniotic fluid cells were deficient in arylsulfatase A, so two possibilities were indicated: the fetus was affected with MLD or had the pseudodeficiency phenotype. The only known biochemical test to differentiate the two enzyme deficient phenotypes is cerebroside sulfate loading of growing fibroblasts. The pseudodeficient cells hydrolyze the incorporated sulfatide as efficiently as control cells, whereas MLD cells show no hydrolysis. Application of this test to the at risk cultured amniotic fluid cells resulted in appreciable uptake of the sulfolipid, but no hydrolysis. Control amniotic fluid cell cultures hydrolyzed 82 to 95% of the incorporated sulfatide. Therefore, an affected fetus was indicated. Fibroblasts derived from the aborted fetus showed a deficiency of arylsulfatase A and a similar inability to hydrolyze cerebroside sulfate in the loading test. The loading technique allowed the prenatal diagnosis of MLD when the arylsulfatase A analysis was equivocal.
 ...
PMID:Prenatal diagnosis of metachromatic leukodystrophy in a family with pseudo arylsulfatase A deficiency by the cerebroside sulfate loading test. 610 22

A very high incidence of late infantile metachromatic leukodystrophy (MLD) (1/75 live births) was found in the Jewish Habbanite community which constitutes a genetic isolate of about 1,000-1,200 individuals. Screening in this population for aryl sulfatase A (ASA) levels in married adults revealed a carrier frequency for MLD of 17% and identified six couples of whom both partners were heterozygotes (6% of screened couples). In three pregnancies of these couples, prenatal diagnosis for the detection of ASA in the fetus was performed.
 ...
PMID:Metachromatic leukodystrophy in the habbanite Jews: high frequency in a genetic isolate and screening for heterozygotes. 610 44

Metachromatic leukodystrophy and multiple sulfatase deficiency disorder are severe neurodegenerative diseases inherited as separate autosomal recessive traits. Arylsulfatase A (aryl-sulfate sulfohydrolase, EC 3.1.6.1) activity is deficient in both diseases but in multiple sulfatase deficiency disorder, activities of arylsulfatases B and C and other sulfatases are also reported to be reduced. Somatic hybrid cell clones produced by fusing cultured fibroblasts from patients with these diseases were isolated by a nonselective technique based on unit-gravity sedimentation. Arylsulfatase A activity was restored in these hybrids. The complemented enzyme resembled the normal arylsulfatase A in heat stability, pH optimum, Km, electrophoretic mobility, and immunologic reactivity. Because a structurally normal enzyme can be restored in a hybrid only though intergenic complementation, these results indicate that the mutations responsible for the deficiency of arylsulfatase A activity in metachromatic leukodystrophy and multiple sulfatase deficiency disorder are nonallelic and that at least two genetic loci control the expression of arylsulfatase A activity in the human genome. Furthermore, arylsulfatase C activity was also restored to normal in the hybrids, indicating that a common sulfatase inhibitor is not the cause of the multiple sulfatse deficiency.
 ...
PMID:Complementation of arylsulfatase A in somatic hybrids of metachromatic leukodystrophy and multiple sulfatase deficiency disorder fibroblasts. 610 62

A family exhibiting a leukocytic arylsulfatase A deficiency, probably inherited in an autosomal recessive manner, differed from patients with typical metachromatic leukodystrophy in that sulfatiduria was absent and there was readily detectable cerebroside sulfatase activity. To our knowledge, this family was unique in that there were no known members with metachromatic leukodystrophy and the only neurologic abnormality was progressive retinal pigment degeneration in the proband.
 ...
PMID:Retinal pigment epithelial degeneration associated with leukocytic arylsulfatase A deficiency. 610 18

Biochemical diagnosis of two cases of metachromatic leukodystrophy /hereditary disease was carried out by means of detection of arylsulfatase A deficiency in leukocytes of impaired children. Prenatal diagnosis of metachromatic leukodystrophy was first performed using estimation of the arylsulfatase A activity in bioptic samples of chorion in 8 week pregnancy. Development of the healthy fetus was diagnosed on the basis of detection of the normal enzymatic activity in the chorion of pregnant woman which had earlier two children with metachromatic leukodystrophy. This conclusion was confirmed by analysis of the fetal tissues in which the normal arylsulfatase A activity was found.
 ...
PMID:[Demonstration of arylsulfatase A deficiency in metachromatic leukodystrophy and prenatal diagnosis of the disease]. 610 2

The cholate and taurodeoxycholate activations of cerebroside sulphate sulphohydrolase (cerebroside-3-sulphate 3-sulphohydrolase, EC 3.1.6.8) activity of arylsulphatase A (aryl-sulphate sulphohydrolase, EC 3.1.6.1) were compared. Taurodeoxycholate caused a sharp peak of response at a concentration of 1.25 mg/ml (type-I activation). Cholate also showed type-I activation but, in addition, it evoked a second, higher, response plateau at concentrations between 5 and 10 mg/ml (type-II activation). At the pH of the reaction, cholate is converted largely to the sparingly soluble free aicd, so at the high concentrations associated with type-II activation, copious precipitates were formed. It was found that the precipitated material was essential for the type-II activation. Type-I activation appears to involve bile salt interaction with substrate, while type-II activation appears to involve enzyme interaction with solid-phase cholic acid. the putative mutant arylsulphatase A in an unusual form of metachromatic leukodystrophy hydolysed cerebroside sulphate only in the presence of high levels of cholate. The type-II activation may thus be simulating a physiological desulphation reaction.
 ...
PMID:Bile salt activation of cerebroside sulphate sulphohydrolase. 610 29

A simple assay technique for the determination of sulfatidase activity in leukocytes has been developed for the reliable diagnosis of metachromatic leukodystrophy (MLD). Sulfatide is tritiated in sphingosine and fatty acid by reduction with [3H]sodium borohydride in alkali in the presence of palladium chloride. This labeled natural substrate for aryl sulfatase A (AsA) is hydrolyzed by normal human leukocytes in 25 mM-acetate buffer, pH 5.0, in the presence of 0.3% sodium taurodeoxycholate. The enzyme activity is greatly improved after dialysis, exhibiting better linearity with protein concentration. It is stimulated maximally by 5 mM-MnCl2 with an apparent Km of 0.17 mM for the substrate. Patients with MLD exhibited virtually no detectable sulfatidase activity although they had residual AsA activity that was measured with the synthetic substrate, p-nitrocatechol sulfate (NCS). Potential heterozygotes could be identified by the sulfatidase assay in instances where the NCS assay for AsA was inconclusive. Several individuals with levels of AsA activity characteristic of MLD, including a few healthy carriers and certain patients with unknown neurological diseases, were shown not to have MLD by the presence of measurable levels of sulfatidase in their leukocytes.
 ...
PMID:Leukocyte sulfatidase for the reliable diagnosis of metachromatic leukodystrophy. 610 67

Two cases of metachromatic leukodystrophy, of the late infantile form are reported. The patients were a girl and a boy of 2 years 10 months old, with initial normal development, but by the age of 18 months began with gait disturbances, difficulty to speak and developed progressive mental deterioration, with signs of long tract involvement, absence of deep tendon reflexes, spasticity, blindness, muscle atrophy and finished in a vegetative state. The diagnosis was made electromyography (signs of denervation), motor nerve conduction velocity (very decreased), assay of arylsulfatase A in the urine (absence of activity), sural nerve biopsy (demyelination and presence of metachromatic granules by the cresyl-violet and toluidine blue) and muscle biopsy (atrophy of type I fibers and presence of metachromatic material in the intramuscular nerve fibers). A quick revision about diagnostic methods, transmission, pathogenesis and variant forms is made.
 ...
PMID:[Metachromatic leukodystrophy: report of 2 cases with histochemistry of nerves and muscles]. 611 Apr 17

A genetic analysis was performed in an isolate in which metachromatic leukodystrophy (MLD) and aryl sulfatase A (ASA) pseudodeficiency are relatively frequent. The frequency of matings at risk and the frequency of ASA pseudodeficiency among parents of MLD patients are compatible with allelism between the gene determining MLD and the gene determining ASA pseudodeficiency. Two independent pedigrees including MLD patients and ASA-deficient healthy individuals also fit the model of allelism.
 ...
PMID:The genetics of the aryl sulfatase A locus. 611 34


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