Haptens, bioconjugates, and antibodies for penthiopyrad immunosensing.

Haptens, bioconjugates, and antibodies for highly sensitive immunochemical analysis of the new-generation fungicide penthiopyrad are described. Two haptens with equivalent carboxylated linkers were prepared, and the purified active esters were efficiently coupled to proteins. The results revealed slightly different antibody-eliciting capacities for the two synthetic derivatives. All of the produced antibodies were specific for penthiopyrad, and showed affinity values in the nanomolar range.

Ikappa-B kinase-2 inhibitor blocks inflammation in human airway smooth muscle and a rat model of asthma.

RATIONALE: Nuclear factor (NF)-kappaB is a transcription factor known to regulate the expression of many inflammatory genes, including cytokines, chemokines, and adhesion molecules. NF-kappaB is held inactive in the cytoplasm, bound to I-kappaB. The removal of I-kappaB, via the actions of inhibitor of kappaB (I-kappaB) kinase-2 (IKK-2), allows NF-kappaB to enter the nucleus. OBJECTIVES: To determine the impact of inhibiting IKK-2 on in vitro and in vivo models of airway inflammation. METHODS: The effect of inhibiting IKK-2 was assessed in stimulated, cultured, primary human airway smooth muscle cells and an antigen-driven rat model of lung inflammation. MEASUREMENTS: The release of cytokines from cultured cells and inflammatory cytokine expression and cellular burden in the lung were determined. MAIN RESULTS: Two structurally distinct molecules and dominant negative technology demonstrated that inhibition of IKK-2 activity completely blocked cytokine release from cultured cells, whereas the two glucocorticoid comparators had limited impact on granulocyte colony-stimulating factor, interleukin 8, and eotaxin release. In addition, in an in vivo antigen-driven model of airway inflammation, the IKK-2 inhibitor blocked NF-kappaB nuclear translocation, which was associated with a reduction in inflammatory cytokine gene and protein expression, airway eosinophilia, and late asthmatic reaction, similar in magnitude to that obtained with budesonide. CONCLUSION: This study demonstrates that inhibiting IKK-2 results in a general reduction of the inflammatory response in vitro and in vivo. Compounds of this class could have therapeutic utility in the treatment of asthma and may, in certain respects, possess a beneficial efficacy profile compared with that of a steroid.

Determination of tiamenidine in biological specimens by radioimmunoassay.

A simple and highly sensitive radioimmunoassay (RIA) procedure has been developed for the determination of the new antihypertensive drug 2-[(2-chloro-4-methyl-3-thienyl)amino]-2-imidazoline (tiamenidine) in serum, plasma and urine. Antisera to tiamenidine were produced in rabbits against its derivatives conjugated to bovine serum albumin. Studies with metabolites and imidazoline derivatives have shown that the antibodies thus produced are specific for tiamenidine. 3H-Labelled drug was used as tracer. The separation of free from antibody-bound tiamenidine was carried out by using polyethylene glycol. The radioimmunoassay (RIA) allows the determination of tiamenidine in 100 microliter biological specimens directly and without extraction down to a detection limit of 20 pg/ml. Reproducibility and accuracy of the assay are good. A sufficient correlation (r = 0.95) was obtained when serum samples were assayed by the RIA and the GC-MS method. The pharmacokinetic profile of the drug was determined in subjects after oral administration of 1 mg tiamenidine using the newly developed RIA. The course of serum levels up to 24 h after treatment may be well described by a Bateman function with an elimination half-life of about 3-5 h. These values correspond sufficiently well with the data obtained from the rate constant of the excretion via urine.