Effects of membrane fatty acid composition on cellular metabolism and oxidative stress in dermal fibroblasts from small and large breed dogs.

There is ample evidence that cell membrane architecture contributes to metabolism and aging in animals; however, the aspects of this architecture that determine the rate of metabolism and longevity are still being debated. The 'membrane pacemaker' hypothesis of metabolism and of aging, respectively, suggest that increased lipid unsaturation and large amounts of polyunsaturated fatty acids (PUFAs) in cell membranes increase the cellular metabolic rate as well as the vulnerability of the cell to oxidative damage, thus increasing organismal metabolic rate and decreasing longevity. Here, we tested these hypotheses by experimentally altering the membrane fatty acid composition of fibroblast cells derived from small and large breed dogs by incubating them in a medium enriched in the monounsaturated fatty acid (MUFA) oleic acid (OA, 18:1) to decrease the total saturation.

Galacto, gluco, manno, and disaccharide-based C-glycosides of 2-amino-2-deoxy sugars.

[reaction: see text] Starting from readily available precursors, selenoglycosides derived from GalNAc, GlcNAc, and ManNAc were prepared by either a one- or a two-step process. The anomeric selenides underwent facile C-Se homolysis to provide the corresponding anomeric radicals, which were trapped with alkenes to give C-glycosides. This provides a general entry to alpha-C-glycosides based on 2-amino-2-deoxy sugars that is also applicable to disaccharide variants.

Homoallyl-Substituted Vinylcyclopropanes from α,β-Unsaturated Ketones and Allylindium Derivatives.

Simply reversing the order of addition of aqueous acid and Et O to the Barbier intermediate 1 of the known indium-mediated allylation leads to unprecedented deoxygenative rearrangements [Eq. (a)].