A comparison of Roche Kinetic Interaction of Microparticles in Solution (KIMS) assay for cannabinoids and GC-MS analysis for 11-nor-9-carboxy-delta9-tetrahydrocannabinol.

In this study, we investigated the effectiveness of the Roche Kinetic Interaction of Microparticles in Solution (KIMS) screening assay for cannabinoid metabolites. Urine specimens (N = 1689) were collected during elimination of cannabinoids from 25 subjects with a history of marijuana use. Specimens were analyzed concurrently for cannabinoid metabolites by a customized Department of Defense (DOD) cannabinoid KIMS kit (50-ng/mL cutoff) and for 11-nor-9-carboxy-delta9-tetrahydrocannabinol (THC-COOH) by GC-MS (15-ng/mL cutoff). As compared to GC-MS results, the sensitivity, specificity, and efficiency of the KIMS assay were 69.7%, 99.8%, and 88.6%, respectively. Many of the false-negative results had GC-MS concentrations between 15 and 26 ng/mL (N = 151). The cannabinoid screening results for the DOD samples tested by the laboratory during the same 8-month period were also evaluated. The linear regression analyses of GC-MS results in the 15-50 ng/mL range and KIMS data resulted in regression coefficients of 0.689 for the research specimens and 0.546 for DOD specimens. The results suggest that the KIMS cannabinoid screening assay is deficient in detecting positives around the cutoff (15-25 ng/mL THC-COOH). This limitation of the KIMS cannabinoid screening method compromises the identification of true positive specimens, therefore reducing the effectiveness of the assay. The success of the DOD program is dependent on sensitive and specific screening assays; the high prevalence of false-negative cannabinoid results compromises the program's primary objective of drug deterrence.

The effects of aspirin and acetaminophen on tetrahymena pyriformis GL growth and macromolecular synthesis.

The effect of aspirin and acetaminophen on Tetrahymena pyriformis GL is examined in this study. The concentration of drug which inhibited T. pyriformis GL growth in 24 hours, indicated as IC50, was 200 micrograms/ml and 580 micrograms/ml for aspirin and acetaminophen, respectively. Macromolecular incorporation study showed that aspirin at 100 micrograms to 400 micrograms/ml had essentially no effect on all parameters examined. Acetaminophen had a significant (P less than 0.01) suppression of 14C-thymidine, 14C-uridine and 14C-acetate uptake, but no effect on 14C-amino acid uptake at concentrations from 400 micrograms to 1200 micrograms/ml. T. pyriformis GL is a useful eukaryocytic single cell organism for drug action study.