Disialogangliosides in bovine adrenal medulla.

Gangliosides were isolated from bovine adrenal medulla by DEAE-Sephadex A-25 and Iatrobeads column chromatography. The disialo fraction contained five major gangliosides, A to E; together they accounted for 4.6% of the total lipid-bound sialic acid.

Characterization of GM1 ganglioside by direct inlet chemical ionization mass spectrometry.

Intact permethylated and permethylated-reduced (LiAlH4) derivatives of GM1 ganglioside were analyzed by direct inlet ammonia chemical ionization (CI) mass spectrometry. In addition, the trimethylsilylated derivative of the permethylated-reduced sample of this ganglioside was similarly analyzed. CI mass spectrometry proves to be a highly satisfactory method for structural studies of GM1 ganglioside because of the simple fragmentation pattern and the presence of prominent molecular ions and fragment ions in the high mass region.

Radioassay method of neuraminidase towards N-acetylneuraminosyl hexasaccharides.

We devised a sensitive method to assay for neuraminidase activities towards alpha-(2 leads to 3)-N-acetylneuraminosyl hexasaccharide and alpha-(2 leads to 6)-N-acetylneuraminosyl hexasaccharide, which were isolated from the urine of a patient with adult sialidosis with partial deficiency of beta-galactosidase. Standard assay conditions for the determination of these neuraminidase activities were established and the radiolabeled reduced derivatives of these substrates were used. The fibroblast neuraminidase had its maximum activity at pH 4.

Measurement of eicosapolyenoic acids in the serum by gas-liquid chromatography-chemical ionization mass spectrometry.

The use of octadeutero eicosatetraenoic acid as an internal standard for the reproducible measurement of serum eicosapolyenoic acids (C20:3, C20:4, and C20:5) by gas-liquid chromatography-chemical ionization mass spectrometry is described. The method has the following advantages. The physicochemical properties of the internal standard and the eicosapolyenoic acids are similar.

Eicosapolyenoic acids of serum lipids of Japanese islanders with low incidence of cardiovascular diseases.

Japanese are unique among the peoples of developed countries in having a high intake of eicosapentaenoic acid (C 20:5) from fresh fish and this may in part contribute to their low incidence of cardiovascular diseases. Mass spectroscopic analyses of eicosapolyenoic acids (C20:3, C20:4 and C20:5) were carried out on the serum of aged persons living on Kohama island in Okinawa and known to have the lowest incidence of cardiovascular diseases in Japan. All but 4 of the 77 persons examined (73.

Partial characterization and studies of fibroblast and leucocyte neuraminidase activities towards sialyloligosaccharides in adult sialidosis and mucolipidosis II and III.

We describe the partial characterization and some properties of fibroblast and leucocyte neuraminidase towards 2 leads to 3 and 2 leads to 6 sialyllacose, and 2 leads to 3 and 2 leads to 6 sialylhexasaccharide which were isolated from the urine of a patient with adult sialidosis with partial beta-galactosidase deficiency. Neuraminidase activities were assayed using the radioactive-labeled derivatives of these saccharide substrates. These neuraminidases (acylneuraminyl hydrolase, EC 3.

Four positional isomers of sialyloligosaccharides isolated from the urine of a patient with sialidosis.

Four positional isomers of sialyloligosaccharides were isolated from the urine of an adult patient with sialidosis with partial deficiency of beta-galactosidase. From structural studies including compositional sugar analysis, exoglycosidase digestion, chemical ionization mass spectrometry, proton nuclear magnetic resonance spectrometry, and methylation analysis, their structures were deduced to be as follows: 1. AcNeu alpha 2 leads to 3 Gal beta 1 leads to 4GlcNac beta 1 leads to 2Man alpha 1 leads to 3Man beta 1 leads to 4GlcNac 2.

Increased synthesis of hexacosanoic acid (C23:0) by cultured skin fibroblasts from patients with adrenoleukodystrophy (ALD) and adrenomyeloneuropathy (AMN).

We studied the metabolism of radioactive stearic acid by cultured skin fibroblasts from patients wtih adrenoleukodystrophy (ALD) and its variant, adrenomyeloneuropathy (AMN), to clarify the mechanism of the increased content of very long chain saturated fatty acids in cholesterol esters and sphingolipids, which are known to be the characteristic biochemical changes in ALD and AMN. A substantial amount of hexacosanoic acid (C26 : 0) wa synthesized from stearic acid by ALD and AMN fibroblasts, whereas only a trace amount of hexacosanoic acid was synthesized by control fibroblasts. This indicates that the primary biochemical defect in ALD and AMN may involved the elongation system of very long chain fatty acids.

Topographical distribution of gamma-aminobutyric acid within the cat thalamus in relation to the basal ganglia, as determined by mass fragmentometry.

Chemical ionization mass spectrometry was introduced for the assay of GABA in the cat brain. The method is quite simple, sensitive, and specific for quantitative analysis. Study of the regional distribution of the GABA content within the thalamus disclosed that the ventromedial nucleus (VM) of the thalamus had a high concentration of GABA.

Urinary sialyloligosaccharides in adult type sialidosis: occurrence of two positional isomers.

Two positional isomers of sialyloligosaccharides were isolated from the urine of a patient with adult type sialidosis with partial deficiency of beta-galactosidase. From structural studies including sugar analysis, enzyme degradation and methylation analysis, the following structures are deduced; 1. alpha-AcNeu-(2 leads to 3)-beta-Gal-(1 leads to 4)-beta-GlcNAc-(1 leads to 2)-alpha-Man-(1 leads to 3)-beta-Man-(1 leads to 4)-GlcNAc 2.

Abnormality of long-chain fatty acids in erythrocyte membrane sphingomyelin from patients with adrenoleukodystrophy.

We have devised an analytical method for the determination of fatty acid composition of erythrocyte membrane sphingomyelin by chemical ionization mass spectrometry combined with capillary column gas-liquid chromatography. Fatty acid composition of erythrocyte membrane sphingomyelin from 8 patients with adrenoleukodystrophy (ALD) and 16 healthy controls were examined by this method. The ratio of hexacosanoic acid (C26:0) to docosanoic acid (C22:0) in erythrocyte membrane sphingomyelin from ALD patients was 2.

Characterization of gangliosides in human leucocytes.

Lipids extracted from leucocyte pellets with chloroform-methanol were applied to a DEAE-Sephadex column an the gangliosides were eluted with 0.2M sodium acetate in methanol. The eluate was desalted by Sephadex G-50 column chromatography.

Characterization of glycosphingolipids by direct inlet chemical ionization mass spectrometry.

Permethylated derivatives of cerebrosides and ceramide di-, tri-, tetra-, and penta-hexosides were analyzed by the direct inlet ammonia chemical ionization (CI) mass spectrometry. In the CI mass spectra, the fragment ions produced by the loss of methanol from the protonated molecular ion were observed in all of the glycosphingolipids. Other fragment ions due to the cleavage of glycosidic moiety were major ones under the CI conditions.

Gangliosides and neutral glycolipids of human adrenal medulla.

Glycolipids were isolated from human adrenal medulla by DEAE-Sephadex A-25 and Iatrobeads column chromatography. The lipid-bound sialic acid was about 234 microgram/g fresh tissue. The glanglioside fraction contained two major gangliosides which accounted for 93% of the total lipid-bound sialic acid.

Myopathy and primary aldosteronism: electronmicroscopic study.

We studied two patients with myopathy and primary aldosteronism. Necrosis and vacuolation of muscle fibers were found on light microscopy. Ultrastructurally, the necrotic areas were characterized by dissolution of myofilaments with degenerative vacuoles.

Adult type neuronal storage disease with neuraminidase deficiency.

We describe a patient with adult-onset neuronal storage disease characterized by myoclonus, cerebellar ataxia, convulsive seizures, cherry-red spots, skeletal dysplasia, mild gargoyle features, inguinal hernia, and angiokeratoma. Cytoplasmic inclusions consistent with lysosomal storage disease were demonstrated in neurons of the autonomic nervous system. Accumulation of GM3 and GM2 gangliosides was found in sympathetic ganglia but a catabolic disturbance of these gangliosides was ruled out by normal levels of GM3 ganglioside sialidase and N-acetyl-beta-hexosaminidase A activities.