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R J Desnick

Publications and source records attributed to R J Desnick.

At least 361 records · Page 20Linked to original sources

Enzyme replacement in Fabry's disease, an inborn error of metabolism.

Two patients with Fabry's disease were infused with normal plasma to provide active enzyme (ceramide trihexosidase) for hydrolysis of the plasma substrate, galactosylgalactosylglucosylceramide. Maximum ceramide trihexosidase activity occurred 6 hours after infusion of the plasma, attaining a level approximately 150 percent of that in normal plasma; enzymatic activity was detectable for 7 days. The amount of accumulated substrate in the plasma of these recipients decreased about 50 percent on day 10 after infusion. Thus, periodic replacement of ceramide trihexosidase activity in the plasma of patients with Fabry's disease might lead to consistently lower amounts of substrate in the plasma and a decrease in its rate of accumulation in tissues.

Adolescent↗

A method for the quantitative determination of neutral glycosphingolipids in urine sediment.

A method is described for the isolation and quantitation of six neutral glycosyl ceramides from human urinary sediment. Total lipids were extracted from sediments of 24-hr urine collections, and the glycosyl ceramides were isolated by silicic acid column chromatography followed by thin-layer chromatography. Methanolysis of the individual glycosyl ceramides yielded methyl glycosides which were quantitated as the trimethylsilyl ethers by gas-liquid chromatography. By this technique, the submicromolar concentrations of six glycosyl ceramides in normal subjects and in individuals with Fabry's disease, an hereditary glycosphingolipid storage disease, were determined. Trihexosyl ceramide (galactosyl-galactosylglucosyl ceramide) and a digalactosyl ceramide accumulated in the urinary sediment of patients with Fabry's disease.

Adolescent↗

Ocular pathology of Fabry's disease in a hemizygous male following renal transplantation.

The ocular pathology of a hemizygous male with Fabry's disease after renal transplantation is reported. The ocular pathology in this patient was essentially identical to that which has previously been reported for both hemizygotes and heterozygotes afflicted with Fabry's disease. Glycolipid deposits and/or osmophilic inclusion bodies were found universally throughout the ocular vasculature. Endothelial, perithelial and smooth muscle cells of the vessel walls were preferentially involved. Iris pigment epithelium was affected as were the corneal epithelium cells. Reduplication of the basement membrane was seen on electron microscopy. Retinal ganglion cells were unaffected. Involvement of the retinal pigment epithelium and the corneal endothelium was documented for the first time.

Adolescent↗

Delta-aminolevulinic acid dehydratase polymorphism: influence on lead levels and kidney function in humans.

Delta-aminolevulinic acid dehydratase (ALAD) polymorphism has been reported to modify lead pharmacokinetics (i.e., individuals who express the ALAD2 allele [ALAD2 subjects] have higher blood lead levels than homozygotes for the ALAD1 allele [ALAD1 subjects]). In our study of 89 lead-exposed workers (7 ALAD2 homozygotes or heterozygotes) and 34 unexposed workers (10 ALAD2 heterozygotes), concentrations of urinary calcium and creatinine were lower in ALAD2 subjects than in ALAD1 subjects (respective medians: calcium--78 mg/l versus 185 mg/l, p = .003; creatinine--11.2 mmol/l versus 14.9 mmol/l, p = .008). No association was found between ALAD genotype and blood lead levels or bone lead levels. However, expression of the ALAD2 allele occurred less frequently among lead-exposed workers than in unexposed controls. The results indicated the presence of ALAD allele-specific differences in kidney function, as well as a possible genetic healthy-worker selection.

Alleles↗