Biomedical subjects
Publications and source records attributed to D Bergemann.
OBJECTIVE: To describe the person of Jan H. van Bemmel from different points of view. METHOD: Triangulation. RESULTS AND CONCLUSIONS: Jan H. van Bemmel successfully contributed to research and education in medical informatics. He inspired a lot of people in The Netherlands and internationally.
A new method for determination of lysergic acid diethylamide (LSD) in body fluids by high-performance liquid chromatography and fluorescence detection was developed based on previously published methods. The new method is suitable for confirmation of samples tested positive by immunoassay, avoiding loss of LSD by absorption to surfaces. The reduced loss of LSD results in improved sensitivity. This is achieved by adding ethylene glycol to the samples, which cover glass surfaces. This principle can similarly be used to improve analysis of other drugs. Body fluids for analysis included urine and whole blood. An internal standard was applied for quantification of LSD. The new method offers satisfying precision data and has a detection limit of less than 0.05 ng/nL.
Different procedures of solid-phase extraction were re-examined and a new solid-phase extraction procedure was developed using gas chromatography-mass spectrometry for the simultaneous detection and quantitation of morphine, 6-monoacetylmorphine, codeine and dihydrocodeine in plasma and whole blood. The effects of different types of sorbent and buffer solutions on the recoveries and purity of the extracts were also studied. Some preparation techniques on whole blood samples were also investigated. The method developed using Chromabond C18 (100) with spiked plasma samples had good recoveries for all opiates of interest: morphine 93.1% +/- 7.4%, 6-monoacetylmorphine 68.0% +/- 6.7%, codeine 77.0% +/- 8.3% and dihydrocodeine 67.9% +/- 8.4%. The detection limit of all compounds was less than 5 micrograms/L. The blank plasma showed no interfering peaks in the GC/MS-analysis.
The report deals with the demands set for a general surgeon in a developing country, which is in a state of conventional war. The pecularities concerning logistics and treatment at the base are dealt with. Conclusions for postgraduate surgical qualification are drawn.