A candidate gene approach of the calcineurin pathway to identify variants associated with clinical outcomes in renal transplantation.

Aim: To investigate the potential influence of variants in genes involved in the calcineurin pathway on the efficacy and toxicity of calcineurin inhibitors in renal transplantation.

Materials & Methods: Twenty-three polymorphisms in thirteen genes were tested in 381 renal transplant recipients receiving ciclosporin (n = 221) or tacrolimus (n = 160) and mycophenolate mofetil. Data were collected prospectively over the first year post-transplantation.

Improving the ex vivo stability of drug ester compounds in rat and dog serum: inhibition of the specific esterases and implications on their identity.

In drug development, it has been noticed that some drug compounds, especially esters, are unstable in serum samples ex vivo. This can lead to a substantial underestimation of the actual drug concentration. The rat and the dog, representing a rodent and non-rodent species, respectively, are widely used in preclinical studies.

Determination of rat serum esterase activities by an HPLC method using S-acetylthiocholine iodide and p-nitrophenyl acetate.

Establishing esterase assays allows the determination and comparison of esteratic activities of tissues of one organism and between organisms. We have developed a high-performance liquid chromatography (HPLC) assay for the determination of S-acetylthiocholine (ATC) and p-nitrophenyl acetate (NPA) hydrolyzing activities of rat serum esterases based on ion pair chromatography with on-line radiochemical and ultraviolet (UV) detection. ATC is a substrate for cholinesterases, whereas NPA is cleaved by a variety of esterases and other proteins (e.