Search PubMed⌕ Search

Biomedical subjects

S Pollet

Publications and source records attributed to S Pollet.

At least 37 records · Page 2Linked to original sources
PubMed1978

Microanalysis of brain lipids: multiple two-dimensional thin-layer chromatography.

The techniques described allow the quantitation of cholesterol, cerebrosides, sulfatides, ethanolamine phospholipids, phosphatidylcholine, -serine, -inositol, and gangliosides on 500 micrograms of lipid. Lipid extraction required sonication. Separation of the lipid classes was performed on TLC glass plates (10 x 10 cm) coated with silica gel HPTLC 60 F 254 Merck using one multiple two-dimensional chromatography. Most of the methods used for quantitation were standard methods that had been scaled down. The procedure was applied to study regional differences in the central nervous system, to analyze cell membranes or subcellular particles, or to analyze pathological biopsies in the central and peripheral nervous systems.

Animals↗
PubMed1977

Myelin consists of a continuum of particles of different density with varying lipid composition: major differences are found between normal mice and quaking mutants.

Mouse brain myelin consists of a continuum of particles of different densities, as shown by sucrose density gradient centrifugation. In normal animals most of the material (65 per cent) is concentrated between 0.6 and 0.7 M sucrose (the maximum being found at 0.66 M sucrose, corresponding to 23 per cent). The density differences among various myelin fractions are related to their protein/lipid ratios, as lighter fractions contain less protein and more lipid. Lipid analysis shows a decrease in the amount of every lipid from the lightest to the heaviest fraction: the light fraction is richer in phosphatidyl-ethanolamine, phosphatidyl-serine and cerebrosides. The distribution is highly abnormal in purified myelin from Quaking mutant ; very low quantities of myelin with normal density are found, but unexpected large amount of high density particles are found, possibly related to a "pre-myelin" material (oligodendrogial) processes which are not maturing into normal myelin).

Animals↗
PubMed1976

[Mouse brain gangliosides during development: demonstration of a new ganglioside].

The study of gangliosides as a function of age indicates that four of the main components GD1a (G3), GD1b (G2), GT1 (G1) and GQ (G0) are present at birth. They increase with age. On thin-layer chromatography, GD1a seems to be maximum at 18 days and GD1b continues to increase. GM1 increases also from birth to adult age. A new ganglioside has been detected in Mouse brain during its development. Not detected 5 days after birth, it is present at 18 days and in maximal quantity at adult age. This compound does not seem to be correlated to myelination process.

Age Factors↗
PubMed1975

[Substrates and products of fatty acid elongation in mouse brain microsomes].

In brain microsomes, palmitate and stearate elongation involve a membrane lipid-bound substrate. After elongation by malonyl-CoA, acyl-products are partially bound to proteins. Acyl-proteins are not found when endogenous fatty acid elongation takes place. In the dysmyelinating Quaking mouse mutants, "stearyl-membrane" substrate formation is normal; thus, the deficiency observed in very long chain fatty acid formation is not due to a lack in substrate formation.

Animals↗