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A monodimensional thin layer chromatography method to separate several sugars of clinical interest is described. The separation and identification of 14 sugars (L-fucose, D-galactose, D-glucose, lactose, N-acetylglucosamine, D-maltose, D-manose, L-sorbase, fructose, D-xylose, glucuronic acid, N-acetyllactosamine, 3' and 6' sialyllactose) and maltodextrines (G(2)-G(8)) is possible by using two different eluents mixtures, as well as two different detection reagents. The method has been applied to separate sugars, maltodextrines and oligosaccharides in several biological fluids (blood, urine and faeces), in an infant milk and in human milk. It is a very simple technique (with a high sensitivity) that can be used in any lab.

Rat liver mitochondria were loaded with cytochrome c by incubation with large amounts of [14C]apocytochrome c. After being washed they were incubated with either more apocytochrome c or cytochrome c. There was no release of labeled proteins from the mitochondria when incubated with cytochrome c. However, there was when incubated with apocytochrome c. The material released showed only one radioactive band which migrated as cytochrome c. Also no release of proteins other than cytochrome c was detected when liver mitochondria isolated from rats injected with [35S]methionine were incubated with apocytochrome c. These results suggest that the level and possibly the turnover of cytochrome c in rat liver mitochondria is regulated by the entry of apocytochrome c into mitochondria.

The polyamines spermidine, spermine and putrescine, by themselves, at physiological concentrations, induce the transport of the precursor of ornithine carbamoyltransferase into isolated rat liver mitochondria. The presence of polyamines in the transport medium results in the approach of both mitochondrial membranes, suggesting a possible role of these molecules in the transport of the precursor of ornithine carbamoyltransferase into mitochondria, by the formation and/or stabilization of mitochondrial structures involved in the transport system.

The precursor of ornithine carbamoyltransferase can be transported in vitro into rat liver mitochondria using the postmitochondrial supernatant from rat liver, a more homologous medium than the commonly used rabbit reticulocyte lysate. The transport of the precursor in the case of reticulocyte lysate requires a standard translation mixture. In the presence of the postmitochondrial supernatant the same is true. However, when the components of the translation mixture were added individually to the postmitochondrial supernatant, it was found that spermidine or spermine, at physiological concentrations, sufficed for the transport of the precursor of ornithine carbamoyltransferase. The activity of the postmitochondrial supernatant was inactivated by trypsin and slightly decreased by RNase treatment; it was not lost by dialysis or by heating at 100 degrees C.