Isolation and identification of cerebrosides from the marine sponge Chondrilla nucula

A cerebroside mixture has been isolated from the marine sponge Chondrilla nucula. Acid-catalyzed methanolysis of this cerebroside mixture afforded methyl glucosides, three long-chain bases, and a mixture of alpha-hydroxy fatty acid methyl esters. The bases were identified as saturated C(17), C(18), and C(19) trihydroxy bases (1,3,4-trihydroxy-2-aminoalkanes) by gas-liquid chromatographic-mass spectrometric analysis of their corresponding trimethylsilyl derivatives. The methyl ester fraction consisted of a mixture of homologous C(16) to C(26) saturated straight-chain alpha-hydroxy esters plus a trace of saturated C(25) iso alpha-hydroxy ester.

Extractives of Australian Timbers. XIV. Triterpene Glycosides of Acacia myrtifolia

Extraction of Acacia myrtifolia has yielded quercitrin and three triterpene glycosides, named myrtifoliosides A, B, and C. Myrtifolioside A, a minor crystalline component, gave erythrodiol and L-arabinose and D-glucose on hydrolysis. Myrtifolioside B (7), C48H80O17,H2O, the major crystalline glycoside, formed erythrodiol, D- glucose, and D-galactose on hydrolysis. Hydrolysis of the methyl ester of the amorphous myrtifolioside C gave methyl oleanolate, D-glucose, and D-galactose. The three glycosides were readily separated on silica gel by elution with a solvent containing sodium acetate.

Ectopic expression of Fgf-4 in chimeric mouse embryos induces the expression of early markers of limb development in the lateral ridge

The biological consequences of constitutive fibroblast growth factor-4 (fgf-4) expression were investigated in chimeric embryos prepared between wild-type host embryos and murine ES cells transfected with a construct in which expression of the murine fgf-4 gene was directed by the phosphoglycerate kinase (PGK-1) promoter. The embryos exhibit abnormalities of the limbs and the anterior central nervous system (CNS). The limb phenotype comprised the induction of outgrowth along the lateral ridge between the definitive fore and hind limbs resembling the early phases of limb development. The CNS defects comprised a complete absence, or marked reduction in forebrain and midbrain structures and rudimentary or absent eye development. Constitutive expression of fgf-4 was also accompanied by ectopic expression of the sonic hedgehog (shh) and msx-1 genes in the lateral ridge. These findings indicate that FGF exhibits multiple activities in early development which include the ability to induce the expression of early markers of limb development in the lateral ridge.