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Search Publications by: Johanna Camara (Fed)

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Displaying 26 - 42 of 42

Recommendations for assessing commutability part 3: based on the calibration effectiveness of a reference material

January 18, 2018
Author(s)
Johanna Camara, Weykamp Cas, Goran Nilsson, Robert Rej, Finlay MacKenzie, Ferruccio Ceriotti, Neil Greenberg, Schimmel Heinz, Gerhard Schumann, Thomas Keller, Vincent Delatour, Mauro Panteghini, Chris Burns, W. Greg Miller
A process is described to assess the commutability of a reference material intended for use as a calibrator based on its ability to fulfill its intended use in a calibration traceability scheme to produce equivalent clinical sample results among different

Baseline Assessment of 25-Hydroxyvitamin D Assay Performance: A Vitamin D Standardization Program (VDSP) Interlaboratory Comparison Study

August 18, 2017
Author(s)
Christopher T. Sempos, Stephen Wise, Karen W. Phinney, Susan Tai, Johanna Camara, Gary L. Myers, Ramon Durazo-Arvizu, Lu Tian, John H. Eckfeldt, Andrew N. Hoofnagle, W. Greg Miller, Lorin M. Bachmann, Ian S. Young, J Pettit, G. Caldwell, A Liu, S P. Brooks, K. Sarafin, M. Thamm, C. Scheidt-Nave, G. B. Mensink, M. Busch, M. Rabenberg, Kevin Cashman, Mairead Kiely, Michael Kinsella, K Galvan, J. Y. Zhang, K OH, S. W. Lee, C. L. Jung, L. Cox, G. Goldberg, K. Guberg, S. Meadows, A. Prentice, G. Swan, A. Tedstone, Graham D. Carter, Julia C. Jones, P. Brannon, R. M. Lucas, P. M. Crump, Glenville Jones, E. Cavalier, Joyce Merkel, J. M. Betz
The Vitamin D Standardization Program (VDSP) coordinated an interlaboratory study to assess the comparability of measurements of total 25-hydroxyvitamin D [25(OH)D] in human serum, which is the primary marker of vitamin D status. A set of 50 individual

Baseline assessment of 25-hydroxyvitamin D reference material and proficiency testing/external quality assurance material commutability - a vitamin D standardization program study

August 10, 2017
Author(s)
Karen W. Phinney, Christopher T. Sempos, Hubert W. Vesper, Julianne C. Botelho, M Dasti, Yasamin Rahmani, Susan Tai, Johanna Camara, Stephen A. Wise, Gary L. Myers, Ramon Durazo-Arvizu, Lu Tian, John H. Eckfeldt, Andrew N. Hoofnagle, W. Greg Miller, Lorin M. Bachmann, Ian S. Young, J Pettit, G. Caldwell, A Liu, S P. Brooks, K. Sarafin, M. Thamm, C. Scheidt-Nave, G. B. Mensink, M. Busch, M. Rabenberg, Kevin Cashman, Mairead Kiely, Albert Flynn, Kirsten D. Dowling, B. Quinn, K OH, S. W. Lee, C. L. Jung, L. Cox, G. Goldberg, K. Guberg, S. Meadows, A. Prentice, G. Swan, Alison Tedstone, Schleicher Rosemary, Christine M. Pfeiffer, Graham D. Carter, Julia Jones, P. Brannon, R. M. Lucas, Neil C. Binkley, P. M. Crump, Donald Wiebe, Glenville Jones, J. M. Betz, C. D. Faigen, Joyce Merkel, Elizabeth A. Yetley, Paul M. Coates
The Vitamin D Standardization Program (VDSP) coordinated a study to assess the commutability of reference materials and proficiency testing/external quality assurance materials for total 25-hydroxyvitamin D [25(OH)D] in human serum, the primary indicator

General steps to standardize the laboratory measurement of serum total 25-hydroxyvitamin D

August 1, 2017
Author(s)
Karen W. Phinney, Christopher T. Sempos, J. M. Betz, Johanna Camara, Graham D. Carter, E. Cavalier, Michael W. Clarke, Kirsten D. Dowling, Ramon Durazo-Arvizu, Andrew N. Hoofnagle, A Liu, Kurtis Sarafin, Stephen A. Wise, Paul M. Coates
The Vitamin D Standardization Program (VDSP) has collaborated with numerous groups and agencies to assemble a set of tools, i.e. a reference measurement system, that can be used to establish traceability of 25-hydroxyvitamin D [25(OH)D] assays to relevant

Value Assignment of Vitamin D Metabolites in Vitamin D Standardization Program (VDSP) Serum Samples

June 16, 2017
Author(s)
Karen W. Phinney, Johanna Camara, Susan Tai, Lane C. Sander, Stephen A. Wise, Linde A. De Grande, Linda M. Thienpont, Antonio M. Possolo, Blaza Toman, Christopher T. Sempos, J. M. Betz, Paul M. Coates
Assay variability has been cited as an obstacle to establishing optimal vitamin D exposure. As part of the Vitamin D Standardization Program (VDSP) effort to standardize the measurement of total 25(OH)D, value assignment of total 25(OH)D in 50 single donor

Development of an Improved Standard Reference Material for Vitamin D Metabolites in Human Serum

April 4, 2017
Author(s)
Karen W. Phinney, Susan S. Tai, Mary Bedner, Johanna Camara, Rosalind R. Chia, Lane C. Sander, Katherine E. Sharpless, Stephen A. Wise, James H. Yen, Rosemary L. Schleicher, Madhulika Chaudhary-Webb, Khin L. Maw, Yasamin Rahmani, Hubert W. Vesper, Joseph M. Betz, Joyce Merkel, Christopher T. Sempos, Paul M. Coates, Ramon Durazo-Arvizu, Kurtis Sarafin, Stephen P. Brooks

Summary of NIST/SIM Chemical Metrology Working Group Training Opportunity: Isotope Dilution-Mass Spectrometry Clinical Measurement Course

December 22, 2016
Author(s)
Jeanita Pritchett, Katrice A. Lippa, Mary Bedner, Carolyn Q. Burdette, Johanna Camara, Brian E. Lang, Michael A. Nelson, Lane C. Sander, Lorna T. Sniegoski
The one week NIST-SIM chemical metrology training opportunity was designed to provide SIM NMI/DI laboratory personnel with in-depth classroom and hands-on laboratory experience for the implementation of isotope dilution/mass spectrometry (ID/MS) methods in

Standardizing 25-Hydroxyvitamin D values from the Canadian Health Measures Survey

September 30, 2015
Author(s)
Kurtis Sarafin, Ramon Durazo-Arvizu, Lu Tian, Karen W. Phinney, Susan Tai, Johanna Camara, Hubert W. Vesper, Joyce M. Merkel, Evan Green, Christopher T. Sempos, Stephen P. Brooks
Background: The Canadian Health Measures survey (CHMS) is an ongoing cross sectional national survey that includes a measure of 25-hydroxyvitamin D (25(OH)D) by Diasorin LIAISON immunoassay. The survey repeats approximately every two years with a new

Development of a Standard Reference Material for Metabolomics Research

November 4, 2013
Author(s)
Karen W. Phinney, Guillaume Ballihaut, Mary Bedner, Johanna Camara, Steven J. Christopher, William C. Davis, Nathan G. Dodder, Brian E. Lang, Stephen E. Long, Mark S. Lowenthal, Elizabeth A. McGaw, Karen E. Murphy, Bryant C. Nelson, Jocelyn L. Prendergast, Jessica L. Reiner, Catherine A. Rimmer, Lane C. Sander, Michele M. Schantz, Katherine E. Sharpless, Lorna T. Sniegoski, Susan S. Tai, Jeanice M. Brown Thomas, Thomas W. Vetter, Michael J. Welch, Stephen A. Wise, Laura J. Wood, William F. Guthrie, Robert C. Hagwood, Stefan D. Leigh, James H. Yen, Nien F. Zhang, Madhu Chaurhary-Webb, Huiping Chen, Bridgette Haynes, Donna J. LaVoie, Leslie F. McCoy, Shahzad S. Momin, Neelima Paladugula, Elizabeth C. Pendergrast, Christine M. Pfeiffer, Carissa D. Powers, Zia Fazili-Qari, Daniel Rabinowitz, Michael E. Rybak, Rosemary L. Schleicher, Mary Xu, Mindy Zhang, Arthur L. Castle, Brandi S. Benford, Gauthier Eppe

Expression and characterization of 15N-labeled human C-reactive protein in Escherichia coli and Pichia pastoris for use in isotope-dilution mass spectrometry

September 1, 2012
Author(s)
Eric L. Kilpatrick, Wei-Li Liao, Johanna Camara, Illarion V. Turko, David M. Bunk
Isotope dilution mass spectrometry using stable isotope labeled internal standards is unsurpassed in its ability to quantify analytes with accuracy and low measurement uncertainty. The extension of this technique to proteins relies upon the expression of