Sialosyl-lactosylceramide, GM3, is the major ganglioside of human liver, where it constitutes more than 90% of the total lipid-bound sialic acid. When analyzed by thin-layer chromatography, human liver GM3 migrates as two main spots. They are representative of ganglioside molecular species which differ in the acyl moiety. The faster running spot is mainly composed of molecular species with non-hydroxylated CZ2 -CZ4 acyl chains; the other contains mainly molecular species bearing nonhydroxylated c 1 6 -CIS and a-hydroxylated C16 -C24 acyl chains.In this study the content of the two GM3 molecular species groups was investigated in 31 subjects ranging from 19 to 85 years of age. By thin-layer chromatography we observed that the group of molecular species containing non-hydroxylated CZ2 -C24 acyl chains, decreased linearly with subject age, while that of non-hydroxylated C16 -C18 acyl chains and hydroxylated c 1 6 -C24 acyl chains increased linearly.Fast-atom-bombardment mass spectrometry performed on seven samples from subjects ranging from 21 to 78 years of age demonstrated that the age-dependent increase of the lower spot is caused by an increase in the hydroxylated fatty acid form of GM3, the content of non-hydroxylated C16 -Cls fatty acid species remaining constant with age Gangliosides are constituents of the plasma membranes of vertebrate cells [l]. Their structure is composed of a hydrophylic sialic-acid-containing oligosaccharide chain and of a double-chained hydrophobic tail, the ceramide. There are a variety of forms of ceramide molecules, which differ in both the long-chain base moiety and the fatty acid component. Gangliosides are inserted into the outer layer of the plasma membranes through their ceramide moiety, which seems to govern some properties of the membrane microdomain in which the gangliosides are inserted [2 -41.The ganglioside content in human liver has been the subject of two main studies 15, 61. These studies, performed on a single liver sample, have lead to the following conclusions : (a) GM3 is the major liver ganglioside constituting over 90% of the total ganglioside content; (b) GM3 is present as a number of molecular species which differ in the chemical structure of the acyl chain. As described here, these species can be partially separated by thin-layer chromatography.In the course of a survey on the ganglioside composition in tumors and different pathologies involving human liver, we

In our experience, a long time variability for spontaneous liver repair after blunt trauma and non-operative treatment was found, but a parenchymal US normalization was evidenced in a median time shorter than that usually reported in the literature.

Two cases of superior mesenteric artery syndrome are presented. In both, conclusive diagnosis was made noninvasively in the presence of acute symptoms by obtaining details of the duodenum and vessels in a sonographic investigation.

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