Biomedical subjects

Rob Jansen

Publications and source records attributed to Rob Jansen.

5 recordsLinked to original sources

PubMed2003

The European Register for Specialists in Clinical Chemistry and Laboratory Medicine: guide to the Register Version 2-2003 and procedure for re-registration.

The European Communities Confederation of Clinical Chemistry and Laboratory Medicine (EC4) opened a Register for European Chemists in 1997. The operation of the Register is undertaken by a Register Committee (EC4RC). During the last 5 years more than 1,400 clinical chemists entered the register. In this article an update of the first Guide to the Register is given, based on the experience of 5 years of operation and the development of the discipline. The registration is valid for 5 years. In a second part the procedure and the conditions for re-registration are presented.

Accreditation↗

PubMed2002

Covalent binding of nitrogen mustards to the cysteine-34 residue in human serum albumin.

Covalent binding of various clinically important nitrogen mustards to the cysteine-34 residue of human serum albumin, in vitro and in vivo, is demonstrated. A rapid method for detection of these adducts is presented, based on liquid chromatography-tandem mass spectrometry analysis of the adducted tripeptide Cys*-Pro-Phe after digestion of the protein with Pronase.

Binding Sites↗

PubMed2002

The practice of clinical chemistry in the European Union.

The European Communities Confederation of Clinical Chemistry has been actively engaged in raising the level of clinical chemistry in the European Union. Closer contacts between the national societies for clinical chemistry have resulted in more comparable programs for postgraduate training of clinical chemists, closer similarity of contents and practice of the profession in the different countries, and the official registration of professionals. This article reviews some of the characteristics of professional organisation, practice, and regulation in the fifteen European Union countries. Many similarities appear. In half of the countries microbiology, blood-banking and transfusion medicine fall within the domain of clinical chemistry. The minimum number of years for training (university and postgraduate) is eight, but in practice this will extend to 10 or more years. Official regulation of the profession by law exists in a minority of countries. Continuing education and re-registration have not been officially instituted yet in any country, but these issues will be the next steps forward. In those countries that prepare themselves for entering the European Union, training and practice of clinical chemistry are moving towards the common standards of the European Communities Confederation of Clinical Chemistry.

Chemistry, Clinical↗

PubMed2002

Commutability assessment of potential reference materials using a multicenter split-patient-sample between-field-methods (twin-study) design: study within the framework of the Dutch project "Calibration 2000".

BACKGROUND: The Dutch project "Calibration 2000" aims at harmonization of laboratory results via calibration by development of commutable, matrix-based, secondary reference materials. An alternative approach to the NCCLS EP14 protocol for studying commutability of reference materials is presented, the "twin-study design", which in essence is a multicenter, split-patient-sample, between-field-methods protocol. METHODS: The study consisted of the simultaneous analysis of fresh patient sera and potential reference materials (PRMs) for HDL-cholesterol (HDL-C) by 86 laboratories forming 43 laboratory couples. Six subgroups of method combinations were formed. The patient sera were selected and interchanged by each laboratory couple. The PRMs consisted of three types: C37, prepared according to the NCCLS C37 protocol; Fro, frozen selectively pooled human serum; and Lyo, which was the same serum pool as Fro but lyophilized in the presence of sucrose. All PRMs were provided in three HDL-C concentrations. The regression line residuals for the PRMs were normalized by expressing them as multiples of the state-of-the-art within laboratory SD (SD(SA)). In addition, the extra contribution of each PRM to the total measurement uncertainty, CV(Netto), was calculated. RESULTS: Averaged over the three PRM concentrations, 1.6% of the C37 residuals were outside the 3 SD(SA) limit. For the Fro and Lyo PRMs, these values were 2.4% and 11.1%. CV(Netto) values for C37, Fro, and Lyo were 2.9%, 4.3%, and 5.3%, respectively. CONCLUSIONS: The present twin-study design, as a practical alternative to the NCCLS EP14 protocol, is a viable way of studying commutability characteristics of PRMs. The study suggests that the C37 PRMs are the best candidates for a future reference material.

Algorithms↗

PubMed2002

Selection, preparation, and characterization of commutable frozen human serum pools as potential secondary reference materials for lipid and apolipoprotein measurements: study within the framework of the Dutch project "Calibration 2000".

BACKGROUND: The Dutch project "Calibration 2000" aims at harmonization of laboratory results via calibration by development of matrix-based secondary reference materials. We considered the selection, preparation, and characterization of 34 potential reference materials (PRMs). METHODS: Sixteen PRMs were prepared either strictly according to the NCCLS C37-A protocol or in a less stringent and more convenient way. In addition, 18 commercial, so-called human serum-based calibrators or controls were purchased and tested. Lipoprotein integrity was evaluated by examining the physicochemical characteristics of the materials. Commutability of the PRMs was assessed in 86 Dutch clinical laboratories, using a multicenter split-patient-sample between-field-method (twin-study) design. Normalized residuals of the PRMs with respect to the patient regression lines were calculated; in addition, the extra contribution of each PRM to the total measurement uncertainty (CV(Netto)) was calculated. On the basis of these results, the most native PRM was selected to investigate its potential to reduce interlaboratory variation and to improve lipid and apolipoprotein standardization. RESULTS: In general, only the NCCLS C37-A-type materials displayed normalized residuals below the decision limit for commutability and had small CV(Netto) values ranging between 0 and 3.8%. This contrasts with the findings in regularly pooled frozen sera and lyophilized cryoprotected PRMs. In two subsequent external quality assessment surveys, the NCCLS type C37-A materials contributed to reducing the intermethod lipid and (apo)lipoprotein variation to approximately 2-4%. CONCLUSIONS: NCCLS C37-A materials have a strong potential as secondary reference materials, not only for cholesterol but also for HDL-cholesterol, LDL-cholesterol, triglyceride, and apolipoprotein measurements.

Apolipoprotein A-I↗