Genotoxicity evaluation of wood-derived and vegetable oil-derived stanol esters

Plant stanol esters from wood and vegetable oil sources were tested for genotoxicity in bacterial (Salmonella typhimurium) and mammalian cell (L5178Y) gene mutation assays and in a mammalian cell chromosome aberration assay (CHO cells). The two stanol ester formulations were tested separately at doses up to the limit of solubility, with and...

Short-term tests of estrogenic potential of plant stanols and plant stanol esters

To test for potential estrogenic activity of plant stanols and plant stanol esters, two short-term tests were performed. These were the E-screen test, which measures a substance's ability to induce proliferation of estrogen-responsive human breast adenocarcinoma (MCF-7) cells in culture, and an in vivo test, which measures uterotrophic activity...

A novel pyrroleninone cross-link from bovine dentine

The aim was to identify suspect collagen cross-links in dentine, eluting close to known cross-links in ion-exchange HPLC. Bovine tooth roots as source of dentine were powdered, demineralised, reduced, and acid-hydrolysed. Cross-linking amino acids were isolated from the acid hydrolysate by size exclusion, adsorption, and sequential ion exchange...

Identification of the C3H7 moiety of isopropyl- and propylphosphonates by electrospray tandem mass spectrometry

Structure analysis of phosphorus compounds within the framework of the Chemical Weapons Convention requires the specific identification of alkyl substituents on phosphorus. In this work the distinction of the P-propyl substituent in propylphosphonic acid derivatives by electrospray tandem mass spectrometry was investigated. P-Isopropyl and P-n...

Quantitative analysis of O-isopropyl methylphosphonic acid in serum samples of Japanese citizens allegedly exposed to sarin: Estimation of internal dosage

A convenient and rapid micro-anion exchange liquid chromatography (LC) tandem electrospray mass spectrometry (MS) procedure was developed for quantitative analysis in serum of O-isopropyl methylphosphonic acid (IMPA), the hydrolysis product of the nerve agent sarin. The mass spectrometric procedure involves negative or positive ion electrospray...

Electron ionization mass spectrometry of curcumin analogues: An olefin metathesis reaction in the fragmentation of radical cations

The natural compound curcumin, used in cosmetics, traditional medicines and as a spice in food, is known as a multi-factorial anti-inflammatory agent. To study the anti-inflammatory activity of curcumin derivatives, 24 analogues were synthesized and their structures were confirmed by 1H NMR and electron ionization (EI) mass spectrometry. Most...

Catheptic processing of protein antigens: Enzymic and molecular aspects

Processing of most exogenous protein antigens involves restricted intracellular proteolysis to yield fragments that may be bound specifically by MHC class II glycoproteins. This association is required for functional presentation to antigen-specific T lymphocytes. The proteolytic degradation takes place in antigen-presenting cells, in an acidic,...