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A potentiometric stripping analysis method for blood lead determination, using Radiometer Tracelab PSU 22, has been investigated. Hemoglobin precipitation by hydrochloric and perchloric acids mixture allows to obtain the same signal for the same lead concentrations in aqueous standards and various blood samples. Thus it is possible to use a time saving calibration procedure. Equilibration time increase improved method sensitivity and precision. The analysis time was 3 minutes per sample. The detection limit was 0.006 microM/L. The relative standard deviation was 3.6% for 1.351 microM/L and 6% for 0.203 microM/L. The results of 66 determinations obtained by this method and by graphite furnace atomic absorption spectrometry were compared (R=0.991). Potentiometric stripping analysis is less expensive and very convenient for clinical laboratories., (Copyright John Libbey Eurotext 2003)

Lipoprotein (a) [Lp(a)] is a lipoprotein which has a plasma concentration that is highly correlated with cardiovascular disease. In this study, the new Lp(a) assay for the Vitek Immuno-Diagnostic Assay System (VIDAS) developed by bioMérieux was evaluated. This method uses an enzyme linked fluorescent immunoassay (ELFIA) technique. Within-run and between-run reproducibility of the Vidass Lp(a) assay are characterized by coefficients of variation (CV) of 3 to 5.9% and 3.9 to 5.9%, respectively. Using analysis of variance, no statistical difference was shown between ELFIA and immunonephelometric assay (INA). When comparing results of the Vidas Lp(a) test with the INA, a highly significant correlation of r = 0.9708 and regression line equation y = 0.963x-0.037 was found. Interference of lipemia was studied: no influence was observed up to 12.3 mmol l(-1) triglycerides. No interference of haemoglobin was noted for Lp(a) > 0.20 g l(-1). Hyperbilirubinemia ( > 120 micromol l(-1)) led to results being underestimated for concentrations of Lp(a) which were < 0.20 g l(-1). No pre-analytical interference of citrate was measured but pre-analytical interference of EDTA was found. In conclusion, this new fully automated immunofluorimetric Lp(a) assay enables to the rapid, accurate and reliable determination of Lp(a) in blood samples.

Philately is an important source of knowledge on numerous items. Evocation of Louis Pasteur's as well as his disciples life and works throughout stamp collection is a perfect example of this. Born in Dôle in 1822, he spent his youth in Arbois. It is at the Ecole normale supérieure that he performed his work on cristals which led him to establish molecular dissymetry principles. Later, he studied of the fermentation process, he searched the reason of wines' disease and the means to prevent it (i.e. pasteurisation), he solved the problem of the silkworm disease and discovered agents of numerous infectious diseases. He demonstrated scientifically the vaccination principle. In 1885 he tried with success the first human antirabic vaccination. Three years later, the Pasteur Institute was inaugurated. After his death, his works survived in numerous institutes all over the world. Many pasteurians received the Nobel Prize.

Extraction of oyster lipids were carried out on total wet organic tissues with a mixture of chloroform-methanol. The different fractions of polar and not polar lipids were separated by thin layer chromatography (TLC) and the methyl esters of the constituant fatty acids has been prepared by transmethylation a cold for use in subsequent gas-liquid chromatography (open tubular gas chromatography). The oyster contained considerable proportions of C16:0 and heiglhly unsaturated acids (specially in lecithin and cephalin) of C20, C22 series which are characteristic of the lipids of most acquatic plants and animals. Studies were made of the seasonal variations.