DONNEES RECENTES SUR LE METABOLISME DU FER

CLERMONT FD-BCIU-Santé (631132104) / SudocLYON1-BU Santé (693882101) / SudocSudocFranceF

THROMBOPENIES INDUITES PAR L'HEPARINE ET DANAPAROIDE SODIQUE (ETUDE BIBLIOGRAPHIQUE ET EXPERIENCE CLERMONTOISE)

CLERMONT FD-BCIU-Santé (631132104) / SudocLYON1-BU Santé (693882101) / SudocSudocFranceF

Effect of tube filling on plasma freezing for coagulation testing

International audienceBackground: Storage of frozen plasma samples for hemostasis testing is a key step to obtain reliable results. Variables that can affect the quality of plasma during storage include the cryotube type and volume and the tube filling level that conditions the residual air volume. To date, there are only few data on which to base recommendations.Objectives: The aim of this study was to investigate the influence of the tube filling volume (20%, 40%, and 80%) of 2-mL microtubes on frozen plasma for a large panel of hemostasis assays.Methods: For this study, 85 subjects were included, and blood samples were collected from them by venipuncture. After double centrifugation, each sample was aliquoted in 3 2-mL microtubes with different volumes (0.4, 0.8, and 1.6 mL) and stored at - 80. C. At the end of the frozen storage period (3 months +/- 1 week), all aliquots from the sample were tested in the same analytical series for a large panel of hemostasis analyses.Results: Compared with completely filled microtubes (1.6/2 mL), storing frozen plasma in smaller volumes (0.4/2 mL) significantly decreased prothrombin time and activated partial thromboplastin time. Conversely, factor II, V, VII, and X levels were increased. Antithrombin, Russell's viper venom time, and anti-Xa activity in patients treated with heparin were also increased.Conclusion: To store plasma at -80. C for hemostasis analysis, samples should be frozen in small-volume microtubes (<2 mL) with screw caps that are filled to 80% of their volume

Fluorination of PVC medical devices to prevent plasticizers migration

International audienceMedical devices (MD) are often made of plasticized polyvinylchloride (PVC). However, plasticizers may leach out into infused solutions and expose the patients to a toxic risk. The aim of the present work is to fluorinate plasticized PVC tubular MDs to create a barrier layer on their internal surface, and to study the impact of such a chemical treatment on the migration of the plasticizers. Following fluorination by pure molecular fluorine, the physico-chemical characterization of these modified MDs was carried out using various spectroscopic and microscopic techniques or tensile tests, evidencing the formation of covalent C-F bonds on the surface of the treated samples without modification of their mechanical and optical properties. The migration of plasticizers from fluorinated MDs was assessed using gas chromatography coupled with mass spectrometry and was found considerably decreased in comparison with the pristine MDs. After 24 h, the amount of tri-octyltrimellitate plasticizer (TOTM) detected in migrates from fluorinated MDs was even lower than the limit of quantification. Complementary cytotoxicity assays were performed according to the ISO EN 10993-5 standard, showing that the new fluorinated material does not cause a cytotoxic effect on L929 cells