Bufadienolides from Helleborus foetidus and their cytotoxic properties on MCF-7 breast cancer cells.

Twelve bufadienolides and six 19-norbufadienolides were isolated from the aerial parts of Helleborus foetidus. They consist of aglycons and glucosides and include nine previously undescribed compounds and a compound reported for the first time as a genuine natural product. Their structures were established by extensive spectroscopic analysis and the structure and absolute configuration of two previously unreported 3,4-epoxy derivatives were confirmed by single crystal X-ray diffraction analysis.

Toothpastes with Enzymes Support Gum Health and Reduce Plaque Formation.

Enzymes in toothpastes can support host immune responses, and thus maintain oral health. This study aimed to investigate gingival health and the plaque-reducing effects of enzyme-containing toothpastes. A laboratory study tested the antimicrobial potential of different enzyme-containing toothpaste formulations.

An enzymatic method to determine γ-hydroxybutyric acid in serum and urine.

Background: Gamma-hydroxybutyric acid (GHB) has become one of the most dangerous illicit drugs of abuse today. It is used as a recreational and date rape drug because of its depressant effect on the central nervous system, which may cause euphoria, amnesia, respiratory arrest, and coma. There is an urgent need for a simple, easy-to-use assay for GHB determination in urine and blood.

Disparate oxygen responsiveness of two regulatory cascades that control expression of symbiotic genes in Bradyrhizobium japonicum.

Two oxygen-responsive regulatory systems controlling numerous symbiotic genes in Bradyrhizobium japonicum were assayed in free-living cultures for their capacity to activate target genes under different oxygen conditions. NifA- and FixLJ-controlled target genes showed disparate relative expression patterns. Induction of NifA-dependent genes was observed only at oxygen concentrations below 2% in the gas phase, whereas that of FixLJ-controlled targets progressively increased when the oxygen concentration was lowered from 21 to 5, 2, or 0.