Correlation of buccal mucosal transudate collected with a buccal swab and urine levels of cocaine.

In this preliminary study, the level of Benzoyl Ecgonine (BE), a metabolite of cocaine, was compared in urine and buccal mucosal transudate collected by a salt impregnated swab in volunteers admitted for cocaine use. The presence of BE (specificity) was verified by the SYVA EMIT method and the urine and transudate levels measured using the Sigma ELISA methods. Results were confirmed using Gas Chromatography/Mass Spectrometry. In all, 44 patients volunteered, and BE in urine or saliva confirmed that each volunteer had in fact used cocaine. The salt-impregnated swab permitted detection of cocaine or its derivative in 27 of the 44 cases. The paper discusses the possibility of using buccal mucosal transudate as collected by salt-impregnated buccal swab as a minimally-invasive measure of cocaine use. This method would allow positive confirmation by a witness that the sample came from a given patient.

Computer sleep stage scoring--an expert system approach.

This paper describes the application of the expert system concept to sleep stage scoring and is aimed at managing the large variability found in such records. The primary computational burden, sleep parameter calculation, can be relieved by recognizing major classes of recordings or 'somnotypes' having internally consistent sleep parameters for each class but significant differences between classes. The initiation and evolution of somnotypes so as to maintain accuracy while introducing a variety of sleep recordings is treated. The technique is demonstrated on seven all-night recordings resulting in 89.6% accuracy for about 5000 pages of data.