46 results on '"Luthe, H."'
Search Results
2. Multi-center evaluation of analytical performance of the microparticle enzyme immunoassay for sirolimus
- Author
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Wilson, D., Johnston, F., Holt, D., Moreton, M., Engelmayer, J., Gaulier, J.-M., Luthe, H., Marquet, P., Moscato, D., Oellerich, M., Mosso, R., Streit, F., Brunet, M., Fillee, C., Schmid, R., Wallemacq, P., and Barnes, G.
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- 2006
- Full Text
- View/download PDF
3. Cobas 6000 ANALYZER SERIES-ADDED VALUE FOR A LARGE-VOLUME LABORATORY
- Author
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Luthe, H.
- Published
- 2007
4. Automated CSF cytology – is conventional cytology still necessary?
- Author
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Strik, H.M, Luthe, H, Nagel, I, Ehrlich, B, and Bähr, M
- Published
- 2024
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5. Richtigkeit der HDL-Cholesterinmessung
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Niedmann, P. D., Luthe, H., Wieland, H., Schaper, G., and Seidel, D.
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- 1983
- Full Text
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6. Multicenter evaluation of the first automated diagnostic preeclampsia tests: Elecsys SFLT-1 and PIGF
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Schiettecatte, Johan, Russcher, H., Anckaert, Ellen, Mees, Marleen, Leeser, B., Tirelli, A.s., Fiedler, G.m., Luthe, H., Denk, B., Smitz, Johan, Follicle Biology, and Department of Embryology and Genetics
- Subjects
preeclampsia ,Immunoassay ,angiogenic factors ,VEGFR-1 - Abstract
Objectives Performance evaluation of Elecsys® sFlt-1 and PlGF assays. Design and methods Within-, between-run, total imprecision, functional sensitivity, inter-laboratory comparison, method comparison and lot-to-lot reproducibility were evaluated. Results Within- and between-run CVs were below 4% for sFlt-1 > 60 and PlGF > 20 pg/mL. Total imprecision CVs were below 4.3%. Functional sensitivity was 0.999). In healthy pregnancies, the median levels of sFlt-1 remained constant in first (1107 pg/mL) and second trimesters (1437 pg/mL) but increased in the third trimester (2395 pg/mL), while median PlGF levels increased in the first (30 pg/mL) and second trimesters (279 pg/mL) and peaked at 29 to 32 weeks (626 pg/mL) and decreased thereafter (340 pg/mL). The sFlt-1/PlGF ratio is highest in the first trimester (median: 28) but remained constant in the second (median: 4.7) and third trimesters (median: 5.1). In PE/HELPP samples matched for gestational age the sFlt-1 levels were significantly higher (6894-34,624 pg/mL), whereas PlGF levels were lower (9.2-80 pg/mL) and the median sFlt-1/PlGF ratio is much higher (461; range: 121-2614) than in apparently healthy pregnancies (3.6; range: 0.3-105). Conclusion The new Roche Elecsys sFlt-1 and PlGF immunoassay showed excellent precision and reliability. There was a clear difference in the Elecsys sFlt-1/PlGF ratio between samples obtained from women with apparently normal pregnancy at the time of blood collection and those diagnosed with PE/HELLP at the same age of gestation.
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- 2011
7. Multi-center evaluation of analytical performance of the microparticle enzyme immunoassay for sirolimus.
- Author
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UCL - (SLuc) Centre de l'allergie, UCL - (SLuc) Service de biochimie médicale, UCL - (SLuc) Centre de toxicologie clinique, UCL - MD/BICL - Département de biochimie et de biologie cellulaire, Wilson, D., Johnston, F, Holt, D, Moreton, M, Engelmayer, J., Gaulier, J-M, Luthe, H, Marquet, P., Moscato, D, Oellerich, M., Mosso, R, Streit, F, Brunet, M, Fillee, Catherine, Schmid, R., Wallemacq, Pierre, Barnes, G, UCL - (SLuc) Centre de l'allergie, UCL - (SLuc) Service de biochimie médicale, UCL - (SLuc) Centre de toxicologie clinique, UCL - MD/BICL - Département de biochimie et de biologie cellulaire, Wilson, D., Johnston, F, Holt, D, Moreton, M, Engelmayer, J., Gaulier, J-M, Luthe, H, Marquet, P., Moscato, D, Oellerich, M., Mosso, R, Streit, F, Brunet, M, Fillee, Catherine, Schmid, R., Wallemacq, Pierre, and Barnes, G
- Abstract
OBJECTIVES: This study evaluated the analytical characteristics of the new Abbott microparticle enzyme immunoassay (MEIA) for sirolimus. DESIGN AND METHODS: The protocol consisted of nine sections: evaluation of antibody specificity, linearity, detection limit, quantification limit, endogenous interferents, exogenous interferents, precision, proficiency testing panel, and method comparison. RESULTS: The mean analytical detection limit was 0.68 microg/L. The sirolimus concentration corresponding to a total CV of 20% was 1.5 microg/L. Linearity of response was demonstrated across the dynamic range of the assay. Total precision (CVs) at QC control levels from 5 to 22 microg/L ranged from 5.7 to 12.6%. Assay standardization was found to be in good agreement with LC/MS/MS as compared with target values for spiked sirolimus proficiency samples from an international sirolimus proficiency testing program. Good correlations (R values) of the immunoassay were observed in comparisons to LC/MS/MS. R values tended to be lower in comparisons with LC/UV methods. Across both LC-based methods and all study sites, there was approximately 25% overall positive slope bias due to cross reactivity of the MEIA antibody to metabolites of sirolimus. The assay cross-reactivity to metabolites of sirolimus parent drug ranged from 6 to 63%. Assay interferences were minimal with the exception of hematocrit, which presented a negative relationship to measured sirolimus concentration. CONCLUSIONS: The MEIA demonstrated acceptable analytical characteristics for use for routine monitoring of sirolimus immunosuppressive therapy, and is a viable alternative to HPLC-based methods for sirolimus monitoring.
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- 2006
8. WITHDRAWN: Multi-center evaluation of analytical performance of the microparticle enzyme immunoassay for sirolimus.
- Author
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UCL, Wilson, D., Johnston, F, Holt, D, Moreton, M, Engelmayer, J., Gaulier, J-M, Luthe, H, Marquet, P., Moscato, D, Oellerich, M., Mosso, R, Streit, F, Brunet, M, Fillee, C, Schmid, R., Wallemacq, Pierre, Barnes, G, UCL, Wilson, D., Johnston, F, Holt, D, Moreton, M, Engelmayer, J., Gaulier, J-M, Luthe, H, Marquet, P., Moscato, D, Oellerich, M., Mosso, R, Streit, F, Brunet, M, Fillee, C, Schmid, R., Wallemacq, Pierre, and Barnes, G
- Abstract
The Publisher regrets that this article is an accidental duplication of an article that has already been published in Clin. Biochem. 39 (2006) 378-386, doi:10.1016/j.clinbiochem.2006.01.017. The duplicate article has therefore been withdrawn. This article has been withdrawn consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologizes for any inconvenience this may cause.
- Published
- 2006
9. Multicenter evaluation of the first automated Elecsys sFlt-1 and PlGF assays in normal pregnancies and preeclampsia
- Author
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Schiettecatte, J., primary, Russcher, H., additional, Anckaert, E., additional, Mees, M., additional, Leeser, B., additional, Tirelli, A.S., additional, Fiedler, G.M., additional, Luthe, H., additional, Denk, B., additional, and Smitz, J., additional
- Published
- 2010
- Full Text
- View/download PDF
10. WITHDRAWN: Multi-center evaluation of analytical performance of the microparticle enzyme immunoassay for sirolimus
- Author
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Wilson, D., primary, Johnston, F., additional, Holt, D., additional, Moreton, M., additional, Engelmayer, J., additional, Gaulier, J.-M., additional, Luthe, H., additional, Marquet, P., additional, Moscato, D., additional, Oellerich, M., additional, Mosso, R., additional, Streit, F., additional, Brunet, M., additional, Fillee, C., additional, Schmid, R., additional, Wallemacq, P., additional, and Barnes, G., additional
- Published
- 2006
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11. Automated CSF cytology - is conventional cytology still necessary?
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Strik, H.M, primary, Luthe, H, additional, Nagel, I, additional, Ehrlich, B, additional, and Bähr, M, additional
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- 2005
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12. MULTI-CENTER EVALUATION OF AN IMMUNOASSAY FOR THE MEASUREMENT OF SIROLIMUS ON THE ABBOTT IMX® ANALYZER.
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Wilson, D H, primary, Engelmayer, J, additional, Gaulier, J -M, additional, Luthe, H, additional, Marquet, P, additional, Moscato, D, additional, Mosso, R, additional, Oellerich, M, additional, Ramanathan, L, additional, and Sarkozi, L, additional
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- 2004
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13. Renal transport of aromatic acids in patients with phenylketonuria
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Langenbeck, U., Behbehani, A., and Luthe, H.
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- 1981
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14. Analytical Performance of Aufomated Methods for the Determination of the Tumor Markers CA 15-3 and CA 19-9: A Comparison Between Immunoluminometric and Immunomagnetic Assays.
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Heller, C., primary, Binder, L., additional, Gurlit, L., additional, and Luthe, H., additional
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- 1997
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15. Multicentre evaluation of the Boehringer Mannheim/Hitachi 911 Analysis System
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Zaman, Z., primary, Blanckaert, N., additional, Cobbaert, Ch., additional, Gillery, P., additional, Hagemann, P., additional, Luthe, H., additional, Motta, R., additional, Patrono, D., additional, Jionsué, M.-A., additional, Torralba, A., additional, Castiñeiras, M. J., additional, Fuentes-Arderiu, X., additional, Bablok, W., additional, Domke, I., additional, and Stockmann, W., additional
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- 1993
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16. Buchbesprechungen
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Haider, M., Hoffmann, R., and Luthe, H.
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- 1983
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17. Multicentre evaluation of the Boehringer Mannheim/Hitachi 911 Analysis System.
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Zaman, Z., Blanckaert, N., Cobbaert, Ch., Gillery, P., Hagemann, P., Luthe, H., Motta, R., Patrono, D., Jionsué, M.-A., Torralba, A., Castiñeiras, M. J., Fuentes-Arderiu, X., Bablok, W., Domke, I., and Stockmann, W.
- Published
- 1993
18. Erfahrungen mit einer neuen Endpunktmethode zur enzymatischen Kreatininbestimmung im Serum und Urin an Hitachi 717 und 747 Analysatoren.
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Luthe, H. and Hinsch, W.
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- 1995
19. Erprobung der ISE-Einheit des Hitachi 704.
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Luthe, H., Knoke, K.-J., and Stockmann, W.
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- 1988
20. Erprobung des Paramax-Analysensystems.
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Luthe, H. and Knoke, K.-J.
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- 1988
21. Propionazid�mie mit Myelinisierungsst�rungen im ZNS.
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Behbehani, A. W., Lehnert, W., Langenbeck, U., Luthe, H., and Baumgartner, R.
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- 1984
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22. Order entry: general points of view and personal experience.
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Luthe H, Backhaus S, and Montag B
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- 2007
23. Quantitative gas chromatographic mass spectrometric determination of mandelic acid in blood plasma: Comparison of deuterated and homologous internal standards
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Luthe, H., Ludwig-Köhn, Helge, and Langenbeck, U.
- Abstract
Quantitative gas chromatography/mass spectrometry/selected ion monitoring of mandelic acid in plasma in the lower micromolar range has been investigated using both the deuterated compound and a homologue, 2-phenyllactic acid, as internal standards. On chromatography of the TMSi-ester ethers, the latter is less stable than the former. The chromatographic isotope effect observed for deuterated mandelic acid does not suggest a carrier function for this compound. Normal plasma levels of mandelic acid are about 0.5 µM. Only a minor portion of phenyramidol is metabolized to mandelic acid. Preliminary in vivodata indicate that presence of a stereoselective transport system for D(-)-mandelic acid in gastrointestinal tract and possibly kidney.
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- 1983
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24. ChemInform Abstract: Free Radical Additions. Part 11. Kinetics of Free Radical Additions of Bromomalononitrile to Alkenes and PMO Treatment of the Reactivity and Regioselectivity.
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RIEMENSCHNEIDER, K., primary, BARTELS, H. M., additional, DORNOW, R., additional, DRECHSEL-GRAU, E., additional, EICHEL, W., additional, LUTHE, H., additional, MATTER, Y. M., additional, MICHAELIS, W., additional, and BOLDT, P., additional
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- 1987
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25. Keto acids in tissues and biological fluids:O-t-butyldimethylsilyl quinoxalinols as derivatives for sensitive gas chromatographic/mass spectrometric determination
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Langenbeck, U., primary, Luthe, H., additional, and Schaper, Gritta, additional
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- 1985
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26. Free radical additions. Part II. Kinetics of free radical additions of bromomalononitrile to alkenes and PMO treatment of the reactivity and regioselectivity
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Riemenschneider, K., primary, Bartels, H. M., additional, Dornow, R., additional, Drechsel-Grau, E., additional, Eichel, W., additional, Luthe, H., additional, Matter, Y. M., additional, Michaelis, W., additional, and Boldt, P., additional
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- 1987
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27. Letters to the Editors
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Rocchiccioli, F., primary, Langenbeck, U., additional, and Luthe, H., additional
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- 1986
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28. Keto acids in tissues and biological fluids: O-t-butyldimethylsilyl quinoxalinols as derivatives for sensitive gas chromatographic/mass spectrometric determination
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Langenbeck, U., Luthe, H., and Schaper, Gritta
- Abstract
Quinoxalinol t-butyldimethylsilyl ethers were prepared from three branched-chain and from two aliphatic unbranched 2-keto acids. The electron impact (EI) mass spectra display pronounced [M -57]+ions. With 39–51% of total ion current contained within them, sensitivity is greater than on chemical ionization (CI) mass spectrometry of O-trimethylsilyl derivatives. Mass spectra and chromatographic behaviour of these novel keto acid derivatives are discussed and preliminary quantitative data from rat muscle are given.
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- 1985
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29. Performance evaluation of a turbidimetric cystatin C assay on different high-throughput platforms.
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Hansson LO, Grubb A, Lidén A, Flodin M, Berggren A, Delanghe J, Stove V, Luthe H, Rhode KH, Beck C, and Domke I
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- Autoanalysis, Immunoassay methods, Kidney Diseases diagnosis, Kidney Function Tests methods, Nephelometry and Turbidimetry, Reproducibility of Results, Cystatin C blood, Glomerular Filtration Rate
- Abstract
Objective: The goal with this study was to evaluate the analytical performance of a new cystatin C immunoassay (Tina-quant a Cystatin C, Roche Diagnostics GmbH). The evaluation was carried out at four centers according to a standardized protocol., Material and Methods: The Tina-quant a Cystatin C is a latex particle-enhanced immunoturbidimetric assay. Roche cobas 6000, MODULAR ANALYTICS SWA and COBAS INTEGRA instruments were included in the study. Method comparison studies were carried out against two turbidimetric methods (Dako Cystatin C, Gentian Cystatin C), and one nephelometric method (Siemens N-Latex Cystatin C)., Results: Linearity was proven throughout the measuring range from 0.4 to 8 mg/L. Within-run CVs ranged from 0.7-2.8%, and total CVs from 1.4-4.7 % (concentration range 0.6-3.9 mg/L). Comparable results were obtained with paired serum and Li-heparinate plasma samples. Good agreement was achieved in the comparisons between the Tina-quant a Cystatin C assay and the other commercially available cystatin C assays, two different turbidimetric methods (slope range 0.88-1.04, intercept < 0.17 mg/L, r > or = 0.993) and one nephelometric assay (slope range 0.90-1.05, intercept < 0.21 mg/L, r > or = 0.986)., Conclusions: The Tina-quant a Cystatin C assay was shown to be precise and accurate with proven linearity over the measuring range. Good comparability was obtained with other commercially available assays for the determination of cystatin C. The Tina-quant a Cystatin C assay is very well suited for clinical use on routine clinical chemistry analysers to detect renal dysfunction with a 24 h availability.
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- 2010
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30. Clinical utility of a new enzymatic assay for determination of mycophenolic acid in comparison with an optimized LC-MS/MS method.
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van Gelder T, Domke I, Engelmayer J, de Fijter H, Kuypers D, Budde K, Koeger R, Luthe H, and Oellerich M
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- Adolescent, Adult, Animals, Area Under Curve, Chromatography, Liquid, Dose-Response Relationship, Drug, Female, Humans, IMP Dehydrogenase antagonists & inhibitors, Kidney Transplantation, Male, Middle Aged, Reproducibility of Results, Tandem Mass Spectrometry, Young Adult, Immunosuppressive Agents blood, Mycophenolic Acid blood
- Abstract
The goal of this study was to investigate the clinical utility of a new enzymatic assay for use on COBAS INTEGRA systems (Roche Total MPA assay). From 134 patients, plasma mycophenolic acid (MPA) concentrations were measured with both the enzymatic method and a validated liquid chromatography with tandem mass spectrometry (LC-MS/MS) procedure, to compare these assays. The test principle of the enzymatic assay is inhibition of inosine monophosphate dehydrogenase. Method comparison studies revealed good agreement of results (r > 0.99), overall and in patients with delayed graft function or hypoalbuminemia. MPA area under the concentration-time curve (AUCs) obtained with LC-MS/MS (x) and the enzymatic method (y) compared excellent in patients on cyclosporine (y = 1.04x - 1.05, r = 0.992) or tacrolimus (y = 1.02x - 0.63, r = 0.987). MPA exposure determined with either method at different time points after transplantation agreed well (eg, 25th/50th/75th percentile of day 10 AUCs-LC-MS/MS: 25.8/33.8/45.2 versus enzymatic assay: 26.2/34.4/45.3 mg.h/L). AUCs calculated for both methods were lower at the first 3 time points in patients on cyclosporine compared with tacrolimus (week 4 median cyclosporine/tacrolimus: LC-MS/MS 39.6/56.4 versus enzymatic assay 40.5/56.0 mg.h/L). Both LC-MS/MS and the enzymatic methods revealed a tendency toward lower AUCs and predose levels in patients with biopsy-proven acute rejection (BPAR) (day 10 median: 0.9 mg/L with BPAR and 1.7 mg/L without BPAR). The Roche Total MPA assay is a reliable alternative to LC-MS/MS. It can be applied in the clinical setting allowing for easy, fast, and optimized patient management.
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- 2009
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31. Therapeutic drug monitoring and drugs of abuse testing on the cobas 6000 analyzer series: analytical performance under routine-like conditions.
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Brandhorst G, Luthe H, Domke I, Knoke C, Rhode KH, Sauter H, and Oellerich M
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- Chemistry, Clinical instrumentation, Drug Monitoring instrumentation, Humans, Reproducibility of Results, Substance Abuse Detection instrumentation, Chemistry, Clinical methods, Drug Monitoring methods, Pharmaceutical Preparations analysis, Substance Abuse Detection methods
- Abstract
Background: The analytical performance of the clinical chemistry module c 501 (cobas 6000 analyzer series) was evaluated for therapeutic drug monitoring and drugs of abuse testing using a spectrum of representative assays. Particular attention was paid to potential interactions between reagents using a simulated routine workload., Methods: Within-run and total imprecision were assessed using a selection of representative reagents. Deviation from a consensus mean was tested using samples from a proficiency testing scheme. Method comparison using routine samples was carried out against the MODULAR ANALYTICS SWA and COBAS INTEGRA 800 analysis systems., Results: Total coefficients of variation (CV) ranged from 1.9% to 7.8% for individual drugs, and from 3.2% to 8.6% for drugs of abuse testing. Results from proficiency test samples were between 81% and 125% of the consensus mean for therapeutic drugs. Method comparisons (Passing-Bablok regression) showed overall good comparability to MODULAR ANALYTICS SWA and COBAS INTEGRA 800 systems, with slopes from 0.93 to 1.17 and correlation coefficients r > 0.98. Imprecision in a simulated routine run was tested using a total of 42 methods (10 therapeutic drug monitoring, 9 drugs of abuse testing, 3 enzymes, 12 substrates, 8 specific protein assays). Imprecision in the reference batch run ranged from 0.7% to 5.0% CV for therapeutic drug monitoring assays, except for digoxin (DIG) (7.3%), and from 0.9% to 7.7% for drugs of abuse testing. The CVs of general clinical chemistry and specific protein tests were within the expected limits of 2% and 4%. CV changes in the simulated routine run were within the expected limits for most assays. Negative DeltaCVs (> or = 2%) for DIG, digitoxin (DIGIT), cannabinoids (THC), and phencyclidine (PCP) may indicate improved performance when running these assays in a simulated routine operation. A positive DeltaCV (> or = 3%) was found for amphetamines (AMPHs)., Conclusions: In conclusion, the cobas c 501 module seems to be well-suited for routine use as consolidated workstation. Except for a potential interaction with AMPH, as indicated by the positive DeltaCV, no significant interferences from different reagents could be observed during this study.
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- 2009
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32. Multicenter evaluation of a new inosine monophosphate dehydrogenase inhibition assay for quantification of total mycophenolic acid in plasma.
- Author
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Brandhorst G, Marquet P, Shaw LM, Liebisch G, Schmitz G, Coffing MJ, Domke I, Streit F, Luthe H, and Oellerich M
- Subjects
- Antibody Specificity, Chromatography, High Pressure Liquid, Cross Reactions, Drug Monitoring, Humans, Inosine Monophosphate metabolism, Mass Spectrometry, NAD metabolism, Reproducibility of Results, Enzyme Inhibitors blood, Enzyme Inhibitors pharmacology, IMP Dehydrogenase antagonists & inhibitors, IMP Dehydrogenase blood, Mycophenolic Acid blood
- Abstract
The performance characteristics of a new inosine monophosphate dehydrogenase inhibition assay for the quantification of total mycophenolic acid (MPA) in plasma (Roche Diagnostics) were assessed in a multicenter evaluation. Validation data were collected from four institutions. Within-run and total imprecision were acceptable (n = 21 for each of 7 materials, coefficients of variation ranging 0.7-9.6%). The lower limit of quantification was 0.31 mg/L. The assay was linear from 0.31 to 15.0 mg/L. Method comparison with validated high-performance liquid chromatography with ultraviolet light or liquid chromatography tandem mass spectrometry methods showed good agreement (coefficients of correlation 0.974-0.994, slopes 1.01-1.17, intercepts -0.17 to 0.06). There was no difference found between results from different transplant types (cardiac vs. renal) or comedications (cyclosporine vs. tacrolimus). The recovery of samples from a proficiency testing scheme was acceptable. The cross-reactivity of AcMPAG, an in vitro active metabolite of MPA, was examined by adding AcMPAG to a pool of patient samples and subsequent quantification. MPA overestimation by AcMPAG cross-reactivity was found to be low (<5%). Thus, this interference is expected to be clinically irrelevant. In conclusion, the Roche Total MPA assay is a promising alternative for MPA quantification where chromatographic methods are not available.
- Published
- 2008
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33. Increasing Efficiency and Quality by Consolidation of Clinical Chemistry and Immunochemistry Systems with MODULAR ANALYTICS SWA.
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Mocarelli P, Horowitz GL, Gerthoux PM, Cecere R, Imdahl R, Ruinemans-Koerts J, Luthe H, Calatayud SP, Salve ML, Kunst A, McGovern M, Ng K, and Stockmann W
- Abstract
MODULAR ANALYTICS Serum Work Area (in USA Integrated MODULAR ANALYTICS, MODULAR ANALYTICS is a trademark of a member of the Roche Group) represents a further approach to automation in the laboratory medicine. This instrument combines previously introduced modular systems for the clinical chemistry and immunochemistry laboratory and allows customised combinations for various laboratory workloads. Functionality, practicability, and workflow behaviour of MODULAR ANALYTICS Serum Work Area were evaluated in an international multicenter study at six laboratories. Across all experiments, 236000 results from 32400 samples were generated using 93 methods. Simulated routine testing which included provocation incidents and anomalous situations demonstrated good performance and full functionality. Heterogeneous immunoassays, performed on the E-module with the electrochemiluminescence technology, showed reproducibility at the same level of the general chemistry tests, which was well within the clinical demands. Sample carryover cannot occur due to intelligent sample processing. Workflow experiments for the various module combinations, with menus of about 50 assays, yielded mean sample processing times of <38 minutes for combined clinical chemistry and immunochemistry requests; <50 minutes including automatically repeated samples. MODULAR ANALYTICS Serum Work Area offered simplified workflow by combining various laboratory segments. It increased efficiency while maintaining or even improving quality of laboratory processes.
- Published
- 2008
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34. AmpliChip CYP450 GeneChip: a new gene chip that allows rapid and accurate CYP2D6 genotyping.
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Heller T, Kirchheiner J, Armstrong VW, Luthe H, Tzvetkov M, Brockmöller J, and Oellerich M
- Subjects
- Humans, Polymerase Chain Reaction, Polymorphism, Restriction Fragment Length, Cytochrome P-450 CYP2D6 genetics, Genetic Variation genetics, Genotype, Pharmacogenetics methods
- Abstract
Methods for Cytochrome P450-2D6 (CYP2D6) genotyping are often time-consuming and laborious, which can restrict their use in pretherapeutic screening programs. Gene chip technology could overcome this problem. The aim of this study was to evaluate CYP2D6 genotyping by a new improved gene chip compared to a PCR-RFLP method. AmpliChip CYP450 GeneChip(R) (AmpliChip) is a microarray hybridization method for genotyping CYP2D6 and CYP2C19. One hundred fifty-nine DNA samples were genotyped both by AmpliChip as well as by PCR-RFLP and, where applicable, by a SNaPshot technique which detects single nucleotide polymorphisms based on the single base extension principle. In 152 of the 159 samples, CYP2D6 genotypes determined with the AmpliChip were in accordance with the results of PCR-RFLP. All seven discrepant samples had gene duplications and were subjected to SNaPshot analysis. SNaPshot results concurred with those of the AmpliChip for six out of seven samples. In the one divergent result, DNA sequencing confirmed that the AmpliChip had assigned the correct genotype. In conclusion, AmpliChip is a highly reliable method for CYP2D6 genotyping that allows the correct determination of all relevant CYP2D6 alleles in one single run. It therefore represents a very efficient and fast method, offering new perspectives for the application of pharmacogenetics in clinical medicine.
- Published
- 2006
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35. Automated cerebrospinal fluid cytology: limitations and reasonable applications.
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Strik H, Luthe H, Nagel I, Ehrlich B, and Bahr M
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- Cell Count instrumentation, Cell Count methods, Central Nervous System pathology, Erythrocytes cytology, False Negative Reactions, False Positive Reactions, Female, Flow Cytometry methods, Granulocytes cytology, Humans, Leukocyte Count, Linear Models, Lymphocytes cytology, Lymphoma cerebrospinal fluid, Lymphoma pathology, Monocytes cytology, Plasmacytoma cerebrospinal fluid, Plasmacytoma pathology, Pneumococcal Infections cerebrospinal fluid, Pneumococcal Infections pathology, Sensitivity and Specificity, Software, Cerebrospinal Fluid cytology, Flow Cytometry instrumentation
- Abstract
Objective: To evaluate the precision and clinical applicability of the Bayer ADVIA 120 cytometer (Bayer Healthcare, Fernwald, Germany) for cerebrospinal fluid (CSF) cell count and differentiation., Study Design: One hundred six analyses of CSF from 98 patients by the ADVIA 120 were compared with routine cell count and microscopic differentiation. Correlation coefficients were calculated., Results: In general, the total cell counts of both methods correlated well. The best correlations were seen at higher cell counts, > or = 100 cells per microliter with < 100 erythrocytes per microliter. The best correlations of cell differentiation were seen for lymphocytes and neutrophils, while the results for monocytes and eosinophils were less precise. In some cases, considerable differences between automated and microscopic cell counts and differentiation were seen that were relevant to clinical decision making. The detection of pathologic cell types, such as hemosiderophages, mitoses and neoplastic cells, was not provided by automated cytometry., Conclusion: When experienced personnel are not available, a preliminary cell count and differentiation between neutrophilic and lymphocytic reactions by automated cytometry may be valuable in allowing initial therapeutic decision making. Since the detection of pathologic cell types is not provided and the precision at low cell counts is only moderate, a personal microscopic evaluation of each sample is still indispensable to avoid misdiagnoses.
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- 2005
36. MODULAR ANALYTICS: A New Approach to Automation in the Clinical Laboratory.
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Horowitz GL, Zaman Z, Blanckaert NJ, Chan DW, Dubois JA, Golaz O, Mensi N, Keller F, Stolz H, Klingler K, Marocchi A, Prencipe L, McLawhon RW, Nilsen OL, Oellerich M, Luthe H, Orsonneau JL, Richeux G, Recio F, Roldan E, Rymo L, Wicktorsson AC, Welch SL, Wieland H, Grawitz AB, Mitsumaki H, McGovern M, Ng K, and Stockmann W
- Abstract
MODULAR ANALYTICS (Roche Diagnostics) (MODULAR ANALYTICS, Elecsys and Cobas Integra are trademarks of a member of the Roche Group) represents a new approach to automation for the clinical chemistry laboratory. It consists of a control unit, a core unit with a bidirectional multitrack rack transportation system, and three distinct kinds of analytical modules: an ISE module, a P800 module (44 photometric tests, throughput of up to 800 tests/h), and a D2400 module (16 photometric tests, throughput up to 2400 tests/h). MODULAR ANALYTICS allows customised configurations for various laboratory workloads. The performance and practicability of MODULAR ANALYTICS were evaluated in an international multicentre study at 16 sites. Studies included precision, accuracy, analytical range, carry-over, and workflow assessment. More than 700 000 results were obtained during the course of the study. Median between-day CVs were typically less than 3% for clinical chemistries and less than 6% for homogeneous immunoassays. Median recoveries for nearly all standardised reference materials were within 5% of assigned values. Method comparisons versus current existing routine instrumentation were clinically acceptable in all cases. During the workflow studies, the work from three to four single workstations was transferred to MODULAR ANALYTICS, which offered over 100 possible methods, with reduction in sample splitting, handling errors, and turnaround time. Typical sample processing time on MODULAR ANALYTICS was less than 30 minutes, an improvement from the current laboratory systems. By combining multiple analytic units in flexible ways, MODULAR ANALYTICS met diverse laboratory needs and offered improvement in workflow over current laboratory situations. It increased overall efficiency while maintaining (or improving) quality.
- Published
- 2005
- Full Text
- View/download PDF
37. Multicenter evaluation of analytical performance of the Liaison troponin I assay.
- Author
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Pagani F, Stefini F, Chapelle JP, Lefèvre G, Graïne H, Luthe H, Engelmayer J, and Panteghini M
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Humans, Immunoassay methods, Immunoassay standards, Linear Models, Male, Middle Aged, Statistics, Nonparametric, Troponin I blood
- Abstract
Objectives: This study evaluated the analytical characteristics of the Liaison immunoassay for cardiac troponin I (cTnI)., Design and Methods: The protocol consisted of eight sections: evaluation of antibody specificity, linearity, detection limit and imprecision, method comparison, evaluation of endogenous interferents, anticoagulant interference, sample stability, and reference values., Results: The assay equally measured free and complexed cTnI. The minimum detectable cTnI concentration was 0.021 microg/l. The cTnI concentration corresponding to a total CV of 10% was 0.056 microg/l. Linearity of response was demonstrated along the entire dynamic range of the assay. Assay interferences were minimal. cTnI concentrations in serum and heparinized plasma were significantly different. Values in EDTA plasma were on average approximately 5% higher than in matched serum, but this difference was not significant. The 99th percentile cTnI value in healthy subjects was 0.036 microg/l., Conclusions: Being sensitive, specific, and precise, the Liaison cTnI assay meets current requirements to aid in the diagnosis of myocardial necrosis.
- Published
- 2004
- Full Text
- View/download PDF
38. Multicentre performance evaluation of the E170 module for modular analytics.
- Author
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Bieglmayer C, Chan DW, Sokoll L, Imdahl R, Kobayashi M, Yamada E, Lilje DJ, Luthe H, Meissner J, Messeri G, Celli A, Tozzi P, Roth HJ, Schmidt FP, Mächler ML, Schuff-Werner P, Zingler C, Smitz J, Schiettecatte J, Vonderschmitt DJ, Pei P, Ng K, Ebert C, Kirch P, Wanger M, McGovern M, Stockmann W, and Kuns A
- Subjects
- Calibration, Ferritins blood, Humans, Male, Prostate-Specific Antigen blood, Reagent Kits, Diagnostic classification, Reagent Kits, Diagnostic standards, Sensitivity and Specificity, Software, Thyrotropin blood, Time, Troponin blood, Chemistry, Clinical methods, Reproducibility of Results
- Abstract
The E170 module was evaluated at 13 sites in an international multicentre study. The objective of the study was to assess the analytical performance of 49 analytes, and to collect feedback on the system's reliability and practicability. The typical, within-run coefficients of variation (CVs) for most of the quantitative assays ranged between 1 and 2% while a range of 2-4% was achieved with the infectious disease methods. Total precision CVs were found to be within the manufacturer's expected performance ranges, demonstrating good concordance of the system's measuring channels and a high reproducibility during the 2-4-week trial period. The functional sensitivity of 11 selected assays met the clinical requirements (e.g., thyreotroponin (TSH) 0.008 mU/l, troponin T 0.02 microg/l, total prostate-specific antigen (PSA) 0.03 microg/l). The E170 showed no drift during an 8-hour period and no relevant reagent carryover. Accuracy was confirmed by ring trial experiments and method comparisons vs. Elecsys 2010. The reliability and practicability of the system's hardware and software met with, or even exceeded, the evaluator's requirements. Workflow studies showed that E170 can cover the combined workload of various routine analysers in a variety of laboratory environment. Throughput and sample processing time requirements were achieved while personnel 'hands-on-time' could be reduced.
- Published
- 2004
- Full Text
- View/download PDF
39. Multicenter analytical performance evaluation of the Elecsys proBNP assay.
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Sokoll LJ, Baum H, Collinson PO, Gurr E, Haass M, Luthe H, Morton JJ, Nowatzke W, and Zingler C
- Subjects
- Evaluation Studies as Topic, Humans, Immunoassay methods, Luminescent Measurements methods, Natriuretic Peptide, Brain blood, Reproducibility of Results, Time Factors, Heart Failure blood, Luminescent Measurements instrumentation, Nerve Tissue Proteins blood, Peptide Fragments blood
- Abstract
The purpose of this multicenter study was to evaluate the technical performance of the automated Elecsys proBNP (brain natriuretic peptide) assay, which is indicated as an aid in the diagnosis of individuals suspected of having congestive heart failure. The Elecsys proBNP assay is an electrochemiluminescent immunoassay employing two polyclonal NT-proBNP-specific antibodies in a sandwich test format. The study was performed on the three Elecsys analyzers (E 1010, E 2010, and E 170) at eight different sites world-wide. Within- and total precision were < or = 3%, with total precision slightly higher on the Elecsys E 170 instrument with multiple modules. Reproducibility among sites and platforms was < 5%. Precision at particularly low NT-proBNP concentrations was assessed down to approximately 25 pg/ml with CVs of 12.6% at 29.2 pg/ml and 9.6% at 38.5 pg/ml for the Elecsys 1010/2010 and E 170, respectively. Linearity was evaluated up to 25,000 pg/ml with a sample-based non-linear response observed with recoveries of < 90% for proBNP concentrations < 10,000 pg/ml. Slopes ranged between 0.92 and 1.02 and intercepts from -5.3 to 10.4 pg/ml (r > or = 0.998) among the three types of analyzers. Slopes were 4.95 and 4.53 in comparison to the Biosite Triage and Shionogi BNP assays. There was no assay interference, and no effect of barrier gels, tube composition, or freeze-thaw. NT-proBNP concentrations in EDTA plasma were up to 10% lower than in serum or heparinized plasma and the analyte was stable at 4 degrees C for up to 72 hours (the maximum time tested). There was no circadian rhythm in normal subjects or congestive heart failure patients and there was no effect of drawing position. In summary, the Elecsys proBNP assay exhibits good technical performance and is suitable for use in routine clinical laboratories to aid in the diagnosis of congestive heart failure.
- Published
- 2004
- Full Text
- View/download PDF
40. Technical performance and diagnostic utility of the new Elecsys neuron-specific enolase enzyme immunoassay.
- Author
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Muley T, Ebert W, Stieber P, Raith H, Holdenrieder S, Nagel D, Fürst H, Roth HJ, Luthe H, Blijenberg BG, Gurr E, Uhl W, von Pawel J, and Drings P
- Subjects
- Adenocarcinoma blood, Adenocarcinoma diagnosis, Adenocarcinoma enzymology, Adult, Aged, Aged, 80 and over, Carcinoma, Large Cell blood, Carcinoma, Large Cell diagnosis, Carcinoma, Large Cell enzymology, Carcinoma, Non-Small-Cell Lung blood, Carcinoma, Non-Small-Cell Lung diagnosis, Carcinoma, Small Cell blood, Carcinoma, Squamous Cell blood, Carcinoma, Squamous Cell diagnosis, Carcinoma, Squamous Cell enzymology, Case-Control Studies, Humans, Immunoassay methods, Immunoenzyme Techniques, Lung enzymology, Lung Neoplasms blood, Middle Aged, Sensitivity and Specificity, Biomarkers, Tumor blood, Carcinoma, Non-Small-Cell Lung enzymology, Carcinoma, Small Cell diagnosis, Carcinoma, Small Cell enzymology, Lung Neoplasms diagnosis, Lung Neoplasms enzymology, Phosphopyruvate Hydratase analysis
- Abstract
This international multicenter study was designed to evaluate the technical performance of the new double-monoclonal, single-step Elecsys neuron-specific enolase (NSE) enzyme immunoassay (EIA) and to assess its utility as a sensitive and specific test for the diagnosis of small-cell lung cancer (SCLC). Intra- and interassay coefficients of variation, determined in five control or serum specimens in six laboratories, ranged from 0.7 to 5.3 (inter-laboratory median: 1.3%) and from 1.3 to 8.5 (inter-laboratory median: 3.4%), respectively. Laboratory-to-laboratory comparability was excellent with respect to recovery and inter-assay coefficients of variation. The test was linear between 0.0 and 320 ng/ml (highest measured concentration). There was a significant correlation between NSE concentrations measured using the Elecsys NSE and the established Cobas Core NSE EIA II in all subjects (n = 723) and in patients with lung cancer (n = 333). However, NSE concentrations were systematically lower (approximately 9%) with the Elecsys NSE than with the comparison test. Based on a specificity of 95% in comparison with the group suffering from benign lung diseases (n = 183), the cut-off value for the discrimination between malignant and benign conditions was set at 21.6 ng/ml. NSE was raised in 73.4% of SCLC patients (n = 188) and was significantly higher (p < 0.01) in extensive (87.8%) as opposed to limited disease (56.7%). NSE was also elevated in 16.0% of the cases with non-small cell lung cancer (NSCLC, n = 374). It is concluded that the Elecsys NSE EIA is a reliable and accurate diagnostic procedure for the measurement of NSE in serum samples. The special merits of this new assay are the wide measuring range (according to manufacturer's declaration up to 370 ng/ml) and a short incubation time of 18 min.
- Published
- 2003
- Full Text
- View/download PDF
41. Detection limit, cut-off and specificity of an improved rapid assay for cardiac troponin T.
- Author
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Baum H, Bertsch T, Bohner J, von Pap KW, Hoff T, Wilke B, Katz N, Luthe H, Luz H, Nagel D, Niederhauser C, van Schaik RH, Aschenneller C, Schul I, and Zerback R
- Subjects
- Biomarkers blood, Coronary Disease blood, Humans, Myocardium chemistry, Regression Analysis, Sensitivity and Specificity, Time Factors, Coronary Disease diagnosis, Reagent Kits, Diagnostic standards, Troponin T blood
- Abstract
The performance of an improved version of the troponin T rapid test TROPT Sensitive was investigated in a multicentre evaluation at twelve centres. The detection limit and the cut-off were determined in a method comparison with Elecsys Troponin T using a total of 365 samples from patients with suspected acute coronary syndromes and 91 samples from healthy blood donors or non-cardiological patients. The analytical specificity was determined by measuring 1271 blood samples from blood donors without any myocardial injury. The test cut-off (90% of results positive) is 0.08 microg/L, and the detection limit is about 0.05 microg/L. The analytical specificity of the test is between 99.7 and 99.9%. With its small area of undefined significance between positive and negative results and its high sensitivity and specificity, TROPT Sensitive is very well suited to the reliable detection of troponin T positive patients with acute coronary syndromes.
- Published
- 2001
42. Cardiac troponin I elevation in acute pulmonary embolism is associated with right ventricular dysfunction.
- Author
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Meyer T, Binder L, Hruska N, Luthe H, and Buchwald AB
- Subjects
- Acute Disease, Double-Blind Method, Female, Humans, Male, Middle Aged, Prospective Studies, Pulmonary Embolism blood, Pulmonary Embolism complications, Troponin I blood, Ventricular Dysfunction, Right blood, Ventricular Dysfunction, Right etiology
- Abstract
Objectives: The purpose of this study was to evaluate the prevalence and diagnostic utility of cardiac troponin I to identify patients with right ventricular (RV) dysfunction in pulmonary embolism., Background: Right ventricular overload resulting from elevated pulmonary resistance is a common finding in major pulmonary embolism. However, biochemical markers to assess the degree of RV dysfunction have not been evaluated so far., Methods: In this prospective, double-blind study we included 36 study patients diagnosed as having acute pulmonary embolism., Results: Among the whole study population, 14 patients (39%) had positive troponin I tests. Ten of 16 patients (62.5%) with RV dilatation had increased serum troponin I levels, while only 4 of 14 patients (28.6%) with elevated troponin I values had a normal RV diameter as assessed by echocardiography, indicating that positive troponin I tests were significantly associated with RV dilatation (p = 0.009). Patients with positive troponin I tests had significantly more segmental defects in ventilation/perfusion lung scans than patients with normal serum troponin I (p = 0.0002)., Conclusions: Our data demonstrate that more than one-third of patients clinically diagnosed as having pulmonary embolism presented with elevated serum troponin I concentrations. Troponin I tests helped to identify patients with RV dilatation who had significantly more segmental defects in lung scans. Thus, troponin I assays are useful to detect minor myocardial damage in pulmonary embolism.
- Published
- 2000
- Full Text
- View/download PDF
43. Superiority of combined CK-MB and troponin I measurements for the early risk stratification of unselected patients presenting with acute chest pain.
- Author
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Meyer T, Binder L, Graeber T, Luthe H, Kreuzer H, Oellerich M, and Buchwald AB
- Subjects
- Aged, Chest Pain mortality, Cohort Studies, Coronary Disease blood, Coronary Disease diagnosis, Coronary Disease mortality, Double-Blind Method, Female, Follow-Up Studies, Humans, Isoenzymes, Male, Middle Aged, Myocardial Infarction blood, Myocardial Infarction diagnosis, Myocardial Infarction mortality, Predictive Value of Tests, Prospective Studies, Risk Assessment, Survival Rate, Chest Pain blood, Creatine Kinase blood, Troponin I blood
- Abstract
Background: Recent studies have suggested that positive troponin I tests are associated with an increased risk of cardiac death during short-term follow-up. However, it is unknown if troponin I tests alone or in addition to CK-MB measurements are superior to predict unfavorable outcome during long-term follow-up., Patients and Methods: In a prospective, double-blind study we assessed the prevalence and prognostic value of combined troponin I and CK-MB tests in an unselected cohort of patients (n = 292) admitted to the emergency department for acute chest discomfort. Patients were grouped according to the diagnosis on discharge in those with acute myocardial infarction (1), unstable angina (2), and noncardiac chest pain (3). Six months after enrollment, death rates were obtained and follow-up interviews were performed with respect to survival, recurrence of chest pain, and myocardial infarction., Results: In patients with evidence of coronary heart disease, the mortality rate for abnormal troponin I and normal CK-MB levels was 5.0%. Baseline troponin I and elevated CK-MB levels were associated with a mortality rate of 4.0%. However, the mortality rate was significantly higher (11.1%) in patients presenting with elevated troponin I and CK-MB values. In patients without myocardial infarction on admission, 10.5% with positive troponin I tests died compared to 1.6% with negative tests. The mortality rate in patients without myocardial infarction was 2.7% for patients with elevated CK-MB but normal troponin I values. In patients with both markers elevated a significantly higher mortality rate (16.7%) was found, representing a 6-fold increase in the death event rate. With the additional knowledge of troponin I values, it could be demonstrated that certain cases were misclassified as having noncardiac chest pain. At least some of the latter patients with above-normal values of troponin I were retrospectively to be reclassified as unstable angina. Acute non-Q-wave myocardial infarctions were occasionally misdiagnosed as either angina pectoris or nonischemic chest pain., Conclusions: Our data suggest the superiority of combined CK-MB and troponin I measurements in clinical practice for the early risk stratification of patients presenting with acute chest pain. In nonmyocardial infarctions, both CK-MB and troponin I convey independent prognostic information with regard to fatal outcome. Troponin I tests in addition to CK-MB measurements contribute to a lower rate of misdiagnoses.
- Published
- 1998
- Full Text
- View/download PDF
44. [Propionic acidemia with myelination disorders of the CNS].
- Author
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Behbehani AW, Lehnert W, Langenbeck U, Luthe H, and Baumgartner R
- Subjects
- Brain pathology, Carboxy-Lyases deficiency, Diagnosis, Differential, Humans, Infant, Infant, Newborn, Male, Methylmalonyl-CoA Decarboxylase, Nerve Degeneration, Acidosis pathology, Demyelinating Diseases pathology, Propionates blood
- Abstract
Clinical course and special diagnostic procedures in a 7 1/2 weeks old dystrophic infant with propionic acidemia are described. The disorder manifested with vomiting and diarrhea within the first week of life when the child was on a cow milk formula. Parenteral nutrition with glucose and electrolytes led to improvement. When oral nutrition with a cow milk formula was implemented again, an acute deterioration with diarrhoea and vomiting occurred. Thus, a diagnosis of cow milk allergy was suggested. There was also a severe muscular hypotony. Oral nutrition with a soybean formula did not prevent further clinical deterioration. At 7 1/2 weeks of age the patient died with symptoms of cardiogenic shock. The correct diagnosis was considered too late and confirmed post mortem. Clinical symptoms in the neonatal period like vomiting, muscular hypotony and failure to thrive should alert the physician to a possible diagnosis of a hereditary organic aciduria. Gas chromatography-mass spectrometry of urinary organics acids, in the present case, established the diagnosis. On autopsy, spongy degenerations were found in CNS.
- Published
- 1984
- Full Text
- View/download PDF
45. Hydrogen exchane at the beta-carbon of amino acids during transamination.
- Author
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Walter U, Luthe H, and Söling HD
- Subjects
- Aminooxyacetic Acid pharmacology, Binding Sites, Glutamates, Hydrogen, Ketoglutaric Acids pharmacology, Kinetics, Magnetic Resonance Spectroscopy, Protein Binding, Protein Conformation, Tritium, Alanine Transaminase metabolism, Aspartate Aminotransferases metabolism
- Abstract
The hydrogen exchange at the Beta-carbon of L-alanine, L-glutamate and L-asparate with water has been examined during transamination catalyzed by glutamic-oxaloacetic transaminase and by glutamic-pyruvic transaminase. A significant hydrogen exchange at the Beta-carbon has been demonstrated during incubation of L-[3-3H]alanine + glutamic-pyruvic transaminase, L-[3-3H]alanine + alpha-oxo-glutarate + glutamic-pyruvic transaminase, L-[3-3H]glutamate + glutamic-oxaloacetic transaminase, L-[3-3H]glutamate + oxaloacetate +glutamic-oxaloacetic transaminase, and L-[3-3H]glutamate + pyruvate + glutamic-pyruvic transaminase as shown by the appearance of 3H2O. No hydrogen exchange at the Beta-carbon of L-glutamate occurred during incubation of L-[3-3H]-glutamate with glutamic-pyruvic transaminase alone. The hydrogen exchaned at the Beta-carbon of L-glutamate coincides with transamination as demonstrated by nuclear magnetic resonance studies of 2H2O-L-glutamate exchange during transamination by glutamic-oxaloacetic transaminase and glutamic-pyruvic transaminase. No hydrogen exchange at the Beta-carbon occurred during transamination of L-aspartate by glutamic-oxaloacetic transaminase as shown by nuclear magnetic resonance spectroscopy and confirmed by nuclear magnetic resonance simulation studies. The results are discussed with special reference to the different equilibria between the pyridoxal form and the pyridoxamine form of glutamic-oxaloacetic transaminase and of glutamic-pyruvic transaminase.
- Published
- 1975
- Full Text
- View/download PDF
46. [Accuracy of HDL cholesterol measurements].
- Author
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Niedmann PD, Luthe H, Wieland H, Schaper G, and Seidel D
- Subjects
- Chemical Phenomena, Chemistry, Cholesterol, HDL, Chromatography, Gas, Chromatography, Thin Layer, Gas Chromatography-Mass Spectrometry, Humans, Cholesterol blood, Lipoproteins, HDL blood
- Abstract
The widespread use of different methods for the determination of HDL-cholesterol (in Europe: sodium phosphotungstic acid/MgCl2) in connection with enzymatic procedures (in the USA: heparin/MnCl2 followed by the Liebermann-Burchard method) but common reference values makes it necessary to evaluate not only accuracy, specificity, and precision of the precipitation step but also of the subsequent cholesterol determination. A high ratio of serum vs. concentrated precipitation reagent (10:1 V/V) leads to the formation of variable amounts of delta-3.5-cholestadiene. This substance is not recognized by cholesterol oxidase but leads to an 1.6 times overestimation by the Liebermann-Burchard method. Therefore, errors in HDL-cholesterol determination should be considered and differences up to 30% may occur between HDL-cholesterol values determined by the different techniques (heparin/MnCl2 - Liebermann-Burchard and NaPW/MgCl2-CHOD-PAP).
- Published
- 1983
- Full Text
- View/download PDF
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