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Waerlop G, Leroux-Roels G, Pagnon A, Begue S, Salaun B, Janssens M, Medaglini D, Pettini E, Montomoli E, Gianchecchi E, Lambe T, Godfrey L, Bull M, Bellamy D, Amdam H, Bredholt G, Cox RJ, Clement F. Proficiency tests to evaluate the impact on assay outcomes of harmonized influenza-specific Intracellular Cytokine Staining (ICS) and IFN-ɣ Enzyme-Linked ImmunoSpot (ELISpot) protocols. J Immunol Methods 2023; 523:113584. [PMID: 37918618 DOI: 10.1016/j.jim.2023.113584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 09/30/2023] [Accepted: 10/28/2023] [Indexed: 11/04/2023]
Abstract
The magnitude and quality of cell-mediated immune responses elicited by natural infection or vaccination are commonly measured by Interferon-ɣ (IFN-ɣ) Enzyme-Linked ImmunoSpot (ELISpot) and Intracellular Cytokine Staining (ICS). To date, laboratories apply a variety of in-house procedures which leads to diverging results, complicates interlaboratory comparisons and hampers vaccine evaluations. During the FLUCOP project, efforts have been made to develop harmonized Standard Operating Procedures (SOPs) for influenza-specific IFN-ɣ ELISpot and ICS assays. Exploratory pilot studies provided information about the interlaboratory variation before harmonization efforts were initiated. Here we report the results of two proficiency tests organized to evaluate the impact of the harmonization effort on assay results and the performance of participating FLUCOP partners. The introduction of the IFN-ɣ ELISpot SOP reduced variation of both background and stimulated responses. Post-harmonization background responses were all lower than an arbitrary threshold of 50 SFU/million cells. When stimulated with A/California and B/Phuket, a statistically significant reduction in variation (p < 0.0001) was observed and CV values were strongly reduced, from 148% to 77% for A/California and from 126% to 73% for B/Phuket. The harmonizing effect of applying an ICS SOP was also confirmed by an increased homogeneity of data obtained by the individual labs. The application of acceptance criteria on cell viability and background responses further enhanced the data homogeneity. Finally, as the same set of samples was analyzed by both the IFN-ɣ ELISpot and the ICS assays, a method comparison was performed. A clear correlation between the two methods was observed, but they cannot be considered interchangeable. In conclusion, proficiency tests show that a limited harmonization effort consisting of the introduction of SOPs and the use of the same in vitro stimulating antigens leads to a reduction of the interlaboratory variation of IFN-ɣ ELISpot data and demonstrate that substantial improvements for the ICS assay are achieved as comparable laboratory datasets could be generated. Additional steps to further reduce the interlaboratory variation of ICS data can consist of standardized gating templates and detailed data reporting instructions as well as further efforts to harmonize reagent and instrument use.
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Affiliation(s)
- Gwenn Waerlop
- Center for Vaccinology (CEVAC), Ghent University and University Hospital, Ghent, Belgium.
| | - Geert Leroux-Roels
- Center for Vaccinology (CEVAC), Ghent University and University Hospital, Ghent, Belgium
| | - Anke Pagnon
- Sanofi, Research Global Immunology, Marcy l'Etoile, France
| | - Sarah Begue
- Sanofi, Research Global Immunology, Marcy l'Etoile, France
| | | | | | - Donata Medaglini
- Laboratory of Molecular Microbiology and Biotechnology, Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Elena Pettini
- Laboratory of Molecular Microbiology and Biotechnology, Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Emanuele Montomoli
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy; VisMederi srl, 53100 Siena, Italy
| | | | - Teresa Lambe
- Oxford Vaccine Group, Department of Paediatrics, Medical Sciences Division, University of Oxford, UK; Chinese Academy of Medical Science (CAMS) Oxford Institute (COI), University of Oxford, United Kingdom
| | - Leila Godfrey
- Oxford Vaccine Group, Department of Paediatrics, Medical Sciences Division, University of Oxford, UK
| | - Maireid Bull
- Oxford Vaccine Group, Department of Paediatrics, Medical Sciences Division, University of Oxford, UK; Chinese Academy of Medical Science (CAMS) Oxford Institute (COI), University of Oxford, United Kingdom
| | - Duncan Bellamy
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Håkon Amdam
- Influenza Centre, Department of Clinical Science, University of Bergen, N5021 Bergen, Norway
| | - Geir Bredholt
- Influenza Centre, Department of Clinical Science, University of Bergen, N5021 Bergen, Norway
| | - Rebecca Jane Cox
- Influenza Centre, Department of Clinical Science, University of Bergen, N5021 Bergen, Norway
| | - Frédéric Clement
- Center for Vaccinology (CEVAC), Ghent University and University Hospital, Ghent, Belgium
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Lee SH, Jung Y, Lee MJ, Lee CH. Development of metal radioactive liquid reference material for proficiency test. Appl Radiat Isot 2023; 200:110970. [PMID: 37540991 DOI: 10.1016/j.apradiso.2023.110970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/21/2023] [Accepted: 07/31/2023] [Indexed: 08/06/2023]
Abstract
This study developed liquid reference materials containing various metals, to be used for quality assurance of radiation measurements of the most common metallic wastes generated during the operation or decommissioning of nuclear power plants. The liquid reference materials were prepared by assuming the dissolution of stainless-steel using acid and melting of the major metals present in the stainless steel, namely Fe, Ni, Cr, and Mn, along with the standard sources (134Cs, 137Cs, 60Co, 90Sr). The theoretical massic activity of the standard sources added to the samples and the measured reference values of the gamma and beta emitters in the samples were compared, and they showed good agreement within a one-sigma confidence interval (k = 1). Using the developed reference materials, a proficiency test was conducted on three domestic labs, and the results were evaluated using Z-score. While the evaluation results showed good agreement between the reference values and the reported values for 137Cs and 60Co, all participating labs reported lower values than the reference value for 134Cs. For 90Sr, two out of the three labs reported significantly higher values than the reference value. Based on the results of this study, the developed metal radioactive liquid reference material is expected to be registered as certified reference material (CRM) in the future. They will be used as the CRM for measuring and ensuring the quality of radioactive metal waste.
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Affiliation(s)
- S H Lee
- Environmental Radioactivity Safety Team, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea.
| | - Y Jung
- Environmental Radioactivity Safety Team, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea
| | - M J Lee
- Environmental Radioactivity Safety Team, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea
| | - C H Lee
- Nuclear Decommissioning Research Institute (NDRI), 17 Techno 4-ro, Yuseong-gu, Daejeon, 34013, Republic of Korea
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Vasilev S, Ciupescu LM, Lalkovski N, Balic D, Vasilev D, Marucci G. Trichinella proficiency testing in Southeastern European countries. Vet Parasitol 2023; 320:109982. [PMID: 37421926 DOI: 10.1016/j.vetpar.2023.109982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 06/28/2023] [Accepted: 06/30/2023] [Indexed: 07/10/2023]
Abstract
In some Southeastern European (SEE) countries, like Serbia, Romania, and Bulgaria, trichinellosis is one of the most important foodborne zoonotic diseases. In those countries, EU regulation and local authorities require the staff of laboratories performing official controls on meat to be properly trained and to check their competence by participating regularly in proficiency testing (PT). PTs are organized by National Reference Laboratories for Trichinella of each country and involve all official laboratories testing meat. In Romania and Bulgaria, the organization of PT for the detection of Trichinella larvae in meat by Magnetic Stirrer Method (MSM) started in 2012. In Croatia and Serbia PT was first organized in 2015 and 2017, respectively. This study presents data on the performance obtained by official laboratories of SEE countries that organize PT at national level and compares the performance obtained by laboratories belonging to different countries. Results suggest that the constant participation in PT leads to an increase in the performance of participating laboratories by positively affecting the staff accuracy in sample testing by MSM. Since the percentage of recovered larvae was in some cases suboptimal (<80%) and occasionally very poor (<40%), there is room for improvement. The regular participation in PT by laboratories involved in official controls on meat intended for human consumption is fundamental to guarantee consumer safety.
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Affiliation(s)
- Sasa Vasilev
- University of Belgrade, Institute for the Application of Nuclear Energy, INEP, Banatska 31b, Belgrade, Serbia.
| | | | - Nikolay Lalkovski
- National Diagnostic and Research Veterinary Medical Institute, Sofia, Bulgaria
| | - Davor Balic
- Croatian Veterinary Institute, Veterinary Department Vinkovci, Croatia
| | - Dragan Vasilev
- University of Belgrade, Faculty of Veterinary Medicine, Bulevar oslobodjenja 18, Belgrade, Serbia
| | - Gianluca Marucci
- European Union Reference Laboratory for Parasite, Istituto Superiore di Sanità, Rome, Italy
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Eckert S, Eilers EJ, Jakobs R, Anaia RA, Aragam KS, Bloss T, Popp M, Sasidharan R, Schnitzler JP, Stein F, Steppuhn A, Unsicker SB, van Dam NM, Yepes S, Ziaja D, Müller C. Inter-laboratory comparison of plant volatile analyses in the light of intra-specific chemodiversity. Metabolomics 2023; 19:62. [PMID: 37351733 DOI: 10.1007/s11306-023-02026-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 06/09/2023] [Indexed: 06/24/2023]
Abstract
INTRODUCTION Assessing intraspecific variation in plant volatile organic compounds (VOCs) involves pitfalls that may bias biological interpretation, particularly when several laboratories collaborate on joint projects. Comparative, inter-laboratory ring trials can inform on the reproducibility of such analyses. OBJECTIVES In a ring trial involving five laboratories, we investigated the reproducibility of VOC collections with polydimethylsiloxane (PDMS) and analyses by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). As model plant we used Tanacetum vulgare, which shows a remarkable diversity in terpenoids, forming so-called chemotypes. We performed our ring-trial with two chemotypes to examine the sources of technical variation in plant VOC measurements during pre-analytical, analytical, and post-analytical steps. METHODS Monoclonal root cuttings were generated in one laboratory and distributed to five laboratories, in which plants were grown under laboratory-specific conditions. VOCs were collected on PDMS tubes from all plants before and after a jasmonic acid (JA) treatment. Thereafter, each laboratory (donors) sent a subset of tubes to four of the other laboratories (recipients), which performed TD-GC-MS with their own established procedures. RESULTS Chemotype-specific differences in VOC profiles were detected but with an overall high variation both across donor and recipient laboratories. JA-induced changes in VOC profiles were not reproducible. Laboratory-specific growth conditions led to phenotypic variation that affected the resulting VOC profiles. CONCLUSION Our ring trial shows that despite large efforts to standardise each VOC measurement step, the outcomes differed both qualitatively and quantitatively. Our results reveal sources of variation in plant VOC research and may help to avoid systematic errors in similar experiments.
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Affiliation(s)
- Silvia Eckert
- Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany
| | - Elisabeth J Eilers
- Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany
| | - Ruth Jakobs
- Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany
| | - Redouan Adam Anaia
- Institute of Biodiversity, Friedrich Schiller University Jena, Jena, Germany
- Molecular Interaction Ecology, German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | | | - Tanja Bloss
- Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany
| | - Moritz Popp
- Research Unit Environmental Simulation, Helmholtz Zentrum München, Munich, Germany
| | - Rohit Sasidharan
- Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany
| | | | - Florian Stein
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Anke Steppuhn
- Department of Molecular Botany, Hohenheim University, Stuttgart, Germany
| | - Sybille B Unsicker
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Nicole M van Dam
- Institute of Biodiversity, Friedrich Schiller University Jena, Jena, Germany
- Molecular Interaction Ecology, German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
- Leibniz Institute of Vegetable and Ornamental Crops, Großbeeren, Germany
| | - Sol Yepes
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Dominik Ziaja
- Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany
| | - Caroline Müller
- Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany.
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Broothaerts W, Beaz Hidalgo R, Buttinger G, Seghers J, Maretti M, Robouch P, Corbisier P. Proficiency of European GMO control laboratories to quantify MON89788 soybean in a meat pâté matrix. Food Control 2023; 145:109454. [PMID: 36875540 DOI: 10.1016/j.foodcont.2022.109454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 10/11/2022] [Accepted: 10/14/2022] [Indexed: 11/07/2022]
Abstract
GMO control laboratories in the EU routinely monitor the presence and content of genetically modified organisms (GMOs) in food and feed products collected from the EU market. As the vast majority of GMOs comprize genetically modified plants, most control samples have a plant-based origin. For the first time, a pilot proficiency test was organised requiring the analysis of GMOs in a meat matrix. Meat pâté, a product in which soybean is occasionally identified, was spiked with GM soybean event MON89788, homogenised by mixing, aliquoted in sachets and frozen. The assigned value was determined by two independent expert laboratories. Several DNA extraction methods were tested and proved to be insufficient for the removal of PCR inhibitors present in the DNA extracts, resulting in a GM content underestimated by at least 30%. This problem was solved either by using hot-start qPCR chemistry or by applying the same method in a digital PCR format. A total of 52 laboratories participated in the study. They were requested to verify the presence of any GM soybean in the test item and to quantify the GM event(s) identified by their method of choice. All but one laboratory identified the MON89788 soybean event present in the pâté matrix. The majority of the quantitative results reported were below the assigned value, but did not deviate more than 50% from it. This study demonstrated the proficiency of most GMO control laboratories for the analysis of GMOs in a meat-based product. It also shows that method optimisation for GMO analysis in meat products is nevertheless advisable.
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Thompson M, Sykes M, Mathieson K, Wood R. Comparison of reproducibility precision on mass fraction in some interlaboratory studies of methods of food analysis. Anal Bioanal Chem 2021; 414:1105-1114. [PMID: 34713313 DOI: 10.1007/s00216-021-03736-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 10/06/2021] [Accepted: 10/15/2021] [Indexed: 11/29/2022]
Abstract
The relationship between reproducibility standard deviation and mass fraction in food analysis has been studied in compilations of statistics from collaborative trials and from proficiency tests. There was a broad tendency for both categories of statistics to follow the Horwitz function although systematic deviations from it were easily detected at both extremes of the mass fraction range (below 10-7 and above 10-2). The two compilations were found to have very similar properties over the whole range of mass fractions, that is from about 10-10 (0.1 ppb) upwards. This similarity has implications for the determination of detection limit.
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Affiliation(s)
- Michael Thompson
- School of Biological and Chemical Sciences, Birkbeck University of London, Malet Street, London, WC1E 7HX, UK
| | - Mark Sykes
- Fera Science Ltd, York Biotech Campus, Sand Hutton, York, YO41 1LZ, UK.
| | - Kenneth Mathieson
- Fera Science Ltd, York Biotech Campus, Sand Hutton, York, YO41 1LZ, UK
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Coolen JPM, Jamin C, Savelkoul PHM, Rossen JWA, Wertheim HFL, Matamoros SP, van Alphen LB, On Behalf Of Sig Bioinformatics In Medical Microbiology Nl Consortium. Centre-specific bacterial pathogen typing affects infection-control decision making. Microb Genom 2021; 7. [PMID: 34356004 PMCID: PMC8549354 DOI: 10.1099/mgen.0.000612] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Whole-genome sequencing is becoming the de facto standard for bacterial outbreak surveillance and infection prevention. This is accompanied by a variety of bioinformatic tools and needs bioinformatics expertise for implementation. However, little is known about the concordance of reported outbreaks when using different bioinformatic workflows. In this multi-centre proficiency testing among 13 major Dutch healthcare-affiliated centres, bacterial whole-genome outbreak analysis was assessed. Centres who participated obtained two randomized bacterial datasets of Illumina sequences, a Klebsiella pneumoniae and a Vancomycin-resistant Enterococcus faecium, and were asked to apply their bioinformatic workflows. Centres reported back on antimicrobial resistance, multi-locus sequence typing (MLST), and outbreak clusters. The reported clusters were analysed using a method to compare landscapes of phylogenetic trees and calculating Kendall–Colijn distances. Furthermore, fasta files were analysed by state-of-the-art single nucleotide polymorphism (SNP) analysis to mitigate the differences introduced by each centre and determine standardized SNP cut-offs. Thirteen centres participated in this study. The reported outbreak clusters revealed discrepancies between centres, even when almost identical bioinformatic workflows were used. Due to stringent filtering, some centres failed to detect extended-spectrum beta-lactamase genes and MLST loci. Applying a standardized method to determine outbreak clusters on the reported de novo assemblies, did not result in uniformity of outbreak-cluster composition among centres.
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Affiliation(s)
- Jordy P M Coolen
- Department of Medical Microbiology and Radboudumc Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Casper Jamin
- Department of Medical Microbiology, Care and Public Health Research Institute (CAPHRI), Maastricht University Medical Center+, Maastricht, The Netherlands
| | - Paul H M Savelkoul
- Department of Medical Microbiology, Care and Public Health Research Institute (CAPHRI), Maastricht University Medical Center+, Maastricht, The Netherlands.,Department of Medical Microbiology & Infection Control, Amsterdam University Medical Centers, location VUmc, Amsterdam, The Netherlands
| | - John W A Rossen
- Department of Medical Microbiology and Infection Prevention, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Heiman F L Wertheim
- Department of Medical Microbiology and Radboudumc Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Sébastien P Matamoros
- Department of Medical Microbiology & Infection Control, Amsterdam University Medical Centers, location VUmc, Amsterdam, The Netherlands
| | - Lieke B van Alphen
- Department of Medical Microbiology, Care and Public Health Research Institute (CAPHRI), Maastricht University Medical Center+, Maastricht, The Netherlands
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Thompson M. On normal and log-normal models imposed on results from proficiency tests for genetically modified organisms (GMO). Anal Bioanal Chem 2021; 413:4699-4705. [PMID: 34120196 DOI: 10.1007/s00216-021-03445-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 05/18/2021] [Accepted: 05/31/2021] [Indexed: 10/21/2022]
Abstract
This work forms a background to the recent discussion about normal and log-normal distributions in the results of proficiency tests for GMO analysis. In order to clear up some common confusions, the paper first covers some basic principles, viz., a comparison of normally and log-normally distributed samples of results at various precisions, and a background to the determination of assigned values and scoring in proficiency tests. Then follows brief discussions on the identification of outliers and the use of 'tests for normality'. In conclusion, there is a broad outline of the steps that may assist a proficiency testing scheme in deciding on a suitable model of dispersion.
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Affiliation(s)
- Michael Thompson
- School of Biological and Chemical Sciences, Birkbeck University of London, Malet Street, London, WC1E 7HX, UK.
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Wylezich C, Calvelage S, Schlottau K, Ziegler U, Pohlmann A, Höper D, Beer M. Next-generation diagnostics: virus capture facilitates a sensitive viral diagnosis for epizootic and zoonotic pathogens including SARS-CoV-2. Microbiome 2021; 9:51. [PMID: 33610182 DOI: 10.1186/s40168-020-00973-z/figures/4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 12/07/2020] [Indexed: 05/18/2023]
Abstract
BACKGROUND The detection of pathogens in clinical and environmental samples using high-throughput sequencing (HTS) is often hampered by large amounts of background information, which is especially true for viruses with small genomes. Enormous sequencing depth can be necessary to compile sufficient information for identification of a certain pathogen. Generic HTS combining with in-solution capture enrichment can markedly increase the sensitivity for virus detection in complex diagnostic samples. METHODS A virus panel based on the principle of biotinylated RNA baits was developed for specific capture enrichment of epizootic and zoonotic viruses (VirBaits). The VirBaits set was supplemented by a SARS-CoV-2 predesigned bait set for testing recent SARS-CoV-2-positive samples. Libraries generated from complex samples were sequenced via generic HTS (without enrichment) and afterwards enriched with the VirBaits set. For validation, an internal proficiency test for emerging epizootic and zoonotic viruses (African swine fever virus, Ebolavirus, Marburgvirus, Nipah henipavirus, Rift Valley fever virus) was conducted. RESULTS The VirBaits set consists of 177,471 RNA baits (80-mer) based on about 18,800 complete viral genomes targeting 35 epizootic and zoonotic viruses. In all tested samples, viruses with both DNA and RNA genomes were clearly enriched ranging from about 10-fold to 10,000-fold for viruses including distantly related viruses with at least 72% overall identity to viruses represented in the bait set. Viruses showing a lower overall identity (38% and 46%) to them were not enriched but could nonetheless be detected based on capturing conserved genome regions. The internal proficiency test supports the improved virus detection using the combination of HTS plus targeted enrichment but also points to the risk of cross-contamination between samples. CONCLUSIONS The VirBaits approach showed a high diagnostic performance, also for distantly related viruses. The bait set is modular and expandable according to the favored diagnostics, health sector, or research question. The risk of cross-contamination needs to be taken into consideration. The application of the RNA-baits principle turned out to be user friendly, and even non-experts can easily use the VirBaits workflow. The rapid extension of the established VirBaits set adapted to actual outbreak events is possible as shown for SARS-CoV-2. Video abstract.
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Affiliation(s)
- Claudia Wylezich
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany.
| | - Sten Calvelage
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Kore Schlottau
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Ute Ziegler
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Anne Pohlmann
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Dirk Höper
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
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10
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Wylezich C, Calvelage S, Schlottau K, Ziegler U, Pohlmann A, Höper D, Beer M. Next-generation diagnostics: virus capture facilitates a sensitive viral diagnosis for epizootic and zoonotic pathogens including SARS-CoV-2. Microbiome 2021; 9:51. [PMID: 33610182 PMCID: PMC7896545 DOI: 10.1186/s40168-020-00973-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 12/07/2020] [Indexed: 05/15/2023]
Abstract
BACKGROUND The detection of pathogens in clinical and environmental samples using high-throughput sequencing (HTS) is often hampered by large amounts of background information, which is especially true for viruses with small genomes. Enormous sequencing depth can be necessary to compile sufficient information for identification of a certain pathogen. Generic HTS combining with in-solution capture enrichment can markedly increase the sensitivity for virus detection in complex diagnostic samples. METHODS A virus panel based on the principle of biotinylated RNA baits was developed for specific capture enrichment of epizootic and zoonotic viruses (VirBaits). The VirBaits set was supplemented by a SARS-CoV-2 predesigned bait set for testing recent SARS-CoV-2-positive samples. Libraries generated from complex samples were sequenced via generic HTS (without enrichment) and afterwards enriched with the VirBaits set. For validation, an internal proficiency test for emerging epizootic and zoonotic viruses (African swine fever virus, Ebolavirus, Marburgvirus, Nipah henipavirus, Rift Valley fever virus) was conducted. RESULTS The VirBaits set consists of 177,471 RNA baits (80-mer) based on about 18,800 complete viral genomes targeting 35 epizootic and zoonotic viruses. In all tested samples, viruses with both DNA and RNA genomes were clearly enriched ranging from about 10-fold to 10,000-fold for viruses including distantly related viruses with at least 72% overall identity to viruses represented in the bait set. Viruses showing a lower overall identity (38% and 46%) to them were not enriched but could nonetheless be detected based on capturing conserved genome regions. The internal proficiency test supports the improved virus detection using the combination of HTS plus targeted enrichment but also points to the risk of cross-contamination between samples. CONCLUSIONS The VirBaits approach showed a high diagnostic performance, also for distantly related viruses. The bait set is modular and expandable according to the favored diagnostics, health sector, or research question. The risk of cross-contamination needs to be taken into consideration. The application of the RNA-baits principle turned out to be user friendly, and even non-experts can easily use the VirBaits workflow. The rapid extension of the established VirBaits set adapted to actual outbreak events is possible as shown for SARS-CoV-2. Video abstract.
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Affiliation(s)
- Claudia Wylezich
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany.
| | - Sten Calvelage
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Kore Schlottau
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Ute Ziegler
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Anne Pohlmann
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Dirk Höper
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
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11
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Mejia R, Cuellar M, Salyards J. Implementing blind proficiency testing in forensic laboratories: Motivation, obstacles, and recommendations. Forensic Sci Int Synerg 2020; 2:293-298. [PMID: 33083776 PMCID: PMC7552087 DOI: 10.1016/j.fsisyn.2020.09.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 09/03/2020] [Indexed: 11/23/2022]
Abstract
Regular proficiency testing of forensic examiners is required at accredited laboratories and widely accepted as an important component of a functioning quality assurance program. Yet, unlike in other testing industries, the majority of forensic laboratories testing programs rely entirely on declared proficiency tests. Some laboratories, primarily federal forensic facilities, have adopted blind proficiency tests, which are also used in the medical and drug testing industries. Blind tests offer advantages. They must resemble actual cases, can test the entire laboratory pipeline, avoid changes in behavior from an examiner knowing they are being tested, and are one of the only methods that can detect misconduct. However, the forensic context present both logistical and cultural obstacles to the implementation of blind proficiency tests. In November 2018, we convened a meeting of directors and quality assurance managers of local and state laboratories to discuss obstacles to the adoption of blind testing and assess successful and potential strategies to overcome them. Here, we compare the situation in forensic science to other testing disciplines, identifying obstacles to the implementation of blind proficiency testing in forensic contexts, and proposing ways to address those issues and increase the ecological validity of proficiency tests at forensic laboratories.
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Affiliation(s)
- Robin Mejia
- Carnegie Mellon University Department of Statistics and Data Science, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA
| | - Maria Cuellar
- University of Pennsylvania Department of Criminology, USA
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12
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Wylezich C, Caccio SM, Walochnik J, Beer M, Höper D. Untargeted metagenomics shows a reliable performance for synchronous detection of parasites. Parasitol Res 2020; 119:2623-2629. [PMID: 32591865 PMCID: PMC7366571 DOI: 10.1007/s00436-020-06754-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 06/03/2020] [Indexed: 12/17/2022]
Abstract
Shotgun metagenomics with high-throughput sequencing (HTS) techniques is increasingly used for pathogen identification and characterization. While many studies apply targeted amplicon sequencing, here we used untargeted metagenomics to simultaneously identify protists and helminths in pre-diagnosed faecal and tissue samples. The approach starts from RNA and operates without an amplification step, therefore allowing the detection of all eukaryotes, including pathogens, since it circumvents the bias typically observed in amplicon-based HTS approaches. The generated metagenomics datasets were analysed using the RIEMS tool for initial taxonomic read assignment. Mapping analyses against ribosomal reference sequences were subsequently applied to extract 18S rRNA sequences abundantly present in the sequence datasets. The original diagnosis, which was based on microscopy and/or PCR, could be confirmed in nearly all cases using ribosomal RNA metagenomics. In addition to the pre-diagnosed taxa, we detected other intestinal eukaryotic parasites of uncertain pathogenicity (of the genera Dientamoeba, Entamoeba, Endolimax, Hymenolepis) that are often excluded from routine diagnostic protocols. The study clearly demonstrates the applicability of untargeted RNA metagenomics for the parallel detection of parasites.
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Affiliation(s)
- Claudia Wylezich
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany.
| | - Simone M Caccio
- Department of Infectious Diseases, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Julia Walochnik
- Molecular Parasitology, Institute for Specific Prophylaxis and Tropical Medicine, Medical University of Vienna, Kinderspitalgasse 15, 1090, Vienna, Austria
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
| | - Dirk Höper
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493, Greifswald-Insel Riems, Germany
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13
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Jobbágy V, Hult M. Performance evaluation of a European scale proficiency test on radon-in-water measurements in Europe. Appl Radiat Isot 2020; 160:109111. [PMID: 32174462 DOI: 10.1016/j.apradiso.2020.109111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 02/17/2020] [Accepted: 03/01/2020] [Indexed: 11/27/2022]
Abstract
In 2018, a Europe wide proficiency test (PT) on measurements of the massic activity of 222Rn in drinking water was organised with the participation of 101 European environmental radioactivity monitoring laboratories. The performance of the participating laboratories was evaluated by comparing submitted results to the reference value using percentage deviation, z-score and zeta-score. It was found that 84% of the participants' results were within the ±20% reference range. When analysing the zeta-score it was found that 76% of the participants' results were acceptable. The accompanied questionnaire and workshop helped to identify practices that could lead to erroneous results. As it was probably the largest scale PT on radon-in-water ever, the evaluation of results is representative of the quality of radon-in-water monitoring in the EU today.
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Affiliation(s)
- Viktor Jobbágy
- European Commission, Joint Research Centre (JRC), Geel, Belgium.
| | - Mikael Hult
- European Commission, Joint Research Centre (JRC), Geel, Belgium
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14
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Charles S, Dodier T, Kaindl M, Kastéropoulos A, Knijnenberg A, Larsson M, Lauper S, Merat N, Niewoehner L, Scholz T, Simon L. Conduction of a round-robin test on a real sample for the identification of gunshot residues by SEM/EDX. Forensic Sci Int 2020; 309:110183. [PMID: 32097863 DOI: 10.1016/j.forsciint.2020.110183] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 01/11/2020] [Accepted: 02/03/2020] [Indexed: 11/27/2022]
Abstract
A round-robin test on the identification of GSR particles by SEM/EDX and involving eleven Institutes was conducted on a real sample, in order to evaluate the possibilities/limitations of using such sample to get additional information (compared to the analysis of the usual synthetic sample used within the framework of the ENFSI proficiency test) about the performances of the SEM/EDX systems. Each Institute was asked to analyse this sample following its own standard operating procedure, and by using all the systems in house, whenever available. Between each Institute, a check of the sample was performed by the organizing Institute (NICC), in order inter alia to monitor any degradation and/or contamination of the sample. A total of about 30 analyses were performed on the sample. For each particle of interest identified on the real sample, the detection effectiveness was monitored, as well as the classification allotted by each Institute. The Institutes were also asked to report some of their measurement parameters, and to send the results as they would have been communicated in their own case report. A quite good agreement was observed with regard to the classification of the particles of interest, since a broad consensus was reached for approximately 75% of these particles. A different classification risk exists for some classes, the barium/antimony classes being probably the most critical, as traces of lead may cause the particles to shift (or not) from the consistent with GSR upper-class to the characteristic of GSR upper-class; in the end, the decision to shift from one class to another strongly depends on local rules. At the end of the campaign, a survey sent to collect experience and lessons learned from this exercise showed that analysing a real sample definitively offers an added value, especially in terms of classification process (during the automatic run and when performing the manual review) of particles.
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Affiliation(s)
- Sébastien Charles
- Institut National de Criminalistique et Criminologie, Bruxelles, Belgium.
| | - Thierry Dodier
- Institut de Recherche Criminelle de la Gendarmerie National, Pontoise, France
| | | | | | | | | | | | - Nadine Merat
- Institut National de Police Scientifique, Toulouse, France
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15
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Özçayan G. Determination of 90Sr activity concentration in black tea powder used as proficiency test sample by the modified liquid scintillation counting method. J Environ Radioact 2020; 211:106079. [PMID: 31666205 DOI: 10.1016/j.jenvrad.2019.106079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 10/14/2019] [Accepted: 10/14/2019] [Indexed: 06/10/2023]
Abstract
Environmental monitoring is very important in nuclear facilities and its surroundings during the construction and operation. It requires many and different radioactivity measurements in order to radiation protection, radioactive waste management and environmental protection. An accurate and reliable determination of Strontium-90 in various environment matrices has been studied with many techniques such as co-precipitation, ion exchange, solvent extraction and extraction chromatography for environmental contamination monitoring purposes. In this study, the method used for dissolution and radiochemical separation to determine strontium-90 activity concentration in tea matrix used as proficiency test sample with liquid scintillation counter was investigated. As a result of these studies, the average mean activity concentration of strontium-90 in proficiency test material was determined as 155 ± 16 Bq kg-1 dry matter (k = 2) by liquid scintillation efficiency tracing (CIEMAT/NIST) method for seven selected samples. This value was also confirmed by Joint Research Center-Geel with the CIEMAT/NIST method. The proficiency test results for consistency were checked by Dioxon's Q-test. Uncertainties arising from counting statistics, background, weighing, half-life, chemical recovery, efficiency and homogeneity were calculated.
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Affiliation(s)
- Gülten Özçayan
- Turkish Atomic Energy Authority, Department of Radiation and Accelerator Technologies, Saray Mah, Atom Cad, No:27 06983 Kahramankazan, Ankara, Turkey.
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16
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Broothaerts W, Cordeiro F, Corbisier P, Robouch P, Emons H. Log transformation of proficiency testing data on the content of genetically modified organisms in food and feed samples: is it justified? Anal Bioanal Chem 2020; 412:1129-36. [PMID: 31863124 DOI: 10.1007/s00216-019-02338-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 11/28/2019] [Accepted: 12/06/2019] [Indexed: 11/27/2022]
Abstract
The outcome of proficiency tests (PTs) is influenced, among others, by the evaluation procedure chosen by the PT provider. In particular for PTs on GMO testing a log-data transformation is often applied to fit skewed data distributions into a normal distribution. The study presented here has challenged this commonly applied approach. The 56 data populations from proficiency testing rounds organised since 2010 by the European Union Reference Laboratory for Genetically Modified Food and Feed (EURL GMFF) were used to investigate the assumption of a normal distribution of reported results within a PT. Statistical evaluation of the data distributions, composed of 3178 reported results, revealed that 41 of the 56 datasets showed indeed a normal distribution. For 10 datasets, the deviation from normality was not statistically significant at the raw or log scale, indicating that the normality assumption cannot be rejected. The normality of the five remaining datasets was statistically significant after log-data transformation. These datasets, however, appeared to be multimodal as a result of technical/experimental issues with the applied methods. On the basis of the real datasets analysed herein, it is concluded that the log transformation of reported data in proficiency testing rounds is often not necessary and should be cautiously applied. It is further shown that the log-data transformation, when applied to PT results, favours the positive performance scoring for overestimated results and strongly penalises underestimated results. The evaluation of the participants' performance without prior transformation of their results may highlight rather than hide relevant underlying analytical problems and is recommended as an outcome of this study. Graphical abstract.
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17
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Weesepoel Y, Silletti E, Alewijn M, Bernreuther A. Importance of harmonised sample preparation for moisture and protein content determinations in official food control laboratories: A poultry meat case study. Food Chem 2019; 301:125291. [PMID: 31387031 DOI: 10.1016/j.foodchem.2019.125291] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 07/25/2019] [Accepted: 07/28/2019] [Indexed: 11/15/2022]
Abstract
Commission Regulation (EC) 543/2008 limits moisture and protein contents in poultry meat. However, this regulation leaves room for interpretation regarding sample homogenisation, potentially affecting comparability of laboratory results. Therefore, a proficiency test and sample homogenisation study were organised amongst 19 European National Reference Laboratories (NRL). In the proficiency test, three different pre-homogenised chicken samples (fillets, drumsticks and carcasses) were analysed. Only one NRL produced unsatisfactory results. In the homogenisation study, NRLs were supplied with uniform fillet, drumstick and carcass materials. Homogenisation was performed according to the NRLs in-house methods. Five NRLs did not return satisfactory results. As these NRLs produced satisfactory results in the proficiency test, their increase in z-scores was related to their homogenisation practices. Overall, scattering of individual results was higher for drumsticks compared to fillets and carcasses. Homogenisation practices for poultry meat introduced significant differences in moisture and protein results and standardisation is therefore advisable.
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Affiliation(s)
- Yannick Weesepoel
- Wageningen Food Safety Research, Part of Wageningen University and Research, P.O. Box 230, 6700 AE Wageningen, the Netherlands.
| | - Erika Silletti
- Wageningen Food Safety Research, Part of Wageningen University and Research, P.O. Box 230, 6700 AE Wageningen, the Netherlands
| | - Martin Alewijn
- Wageningen Food Safety Research, Part of Wageningen University and Research, P.O. Box 230, 6700 AE Wageningen, the Netherlands
| | - Alexander Bernreuther
- European Commission, Joint Research Centre - Geel, Retieseweg 111, 2440 Geel, Belgium
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18
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Jobbágy V, Stroh H, Marissens G, Gruber V, Roth D, Willnauer S, Bernreiter M, von Philipsborn H, Hult M. Evaluation of a radon-in-water pilot- proficiency test. Appl Radiat Isot 2019; 153:108836. [PMID: 31387079 DOI: 10.1016/j.apradiso.2019.108836] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 06/19/2019] [Accepted: 08/01/2019] [Indexed: 11/19/2022]
Abstract
A pilot proficiency test (PT) on measurements of the massic activity of 222Rn in drinking water was organised by JRC-Geel. Fourteen environmental radioactivity monitoring laboratories were invited to participate. The key aim of the study was to test, optimise and stream-line the complete process for conducting such a PT in order to perform a large scale Europe-wide PT in a robust manner. The process involved using all state-of-the art knowledge on sampling, transporting and measuring 222Rn in water. It was found that the majority of the participants' results (92%) were within the ±15% reference range. The pilot-PT showed that the applied process was suitable and can be used for the large scale European PT planned for the third quarter of 2018.
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Affiliation(s)
- Viktor Jobbágy
- European Commission, Joint Research Centre, Directorate for Nuclear Safety and Security, Retieseweg 111, B-2440, Geel, Belgium.
| | - Heiko Stroh
- European Commission, Joint Research Centre, Directorate for Nuclear Safety and Security, Retieseweg 111, B-2440, Geel, Belgium
| | - Gerd Marissens
- European Commission, Joint Research Centre, Directorate for Nuclear Safety and Security, Retieseweg 111, B-2440, Geel, Belgium
| | - Valeria Gruber
- AGES - Austrian Agency for Health and Food Safety, Wieningerstraße 8, 4020, Linz, Austria
| | - Dietmar Roth
- AGES - Austrian Agency for Health and Food Safety, Wieningerstraße 8, 4020, Linz, Austria
| | - Stefan Willnauer
- AGES - Austrian Agency for Health and Food Safety, Wieningerstraße 8, 4020, Linz, Austria
| | - Markus Bernreiter
- AGES - Austrian Agency for Health and Food Safety, Wieningerstraße 8, 4020, Linz, Austria
| | - Henning von Philipsborn
- University of Regensburg, Fakultät für Physik Universität Regensburg, Universitätsstraße 31, D-93053, Regensburg, Germany
| | - Mikael Hult
- European Commission, Joint Research Centre, Directorate for Nuclear Safety and Security, Retieseweg 111, B-2440, Geel, Belgium
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19
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Zhang L, Jin C, Jiang Z, Tang T, Jiang Y, Pan PL. [Comparison of commercial HIV-1 viral load tests by using proficiency test results in China, 2013- 2015]. Zhonghua Liu Xing Bing Xue Za Zhi 2019; 38:1231-1235. [PMID: 28910938 DOI: 10.3760/cma.j.issn.0254-6450.2017.09.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To compare the bio-equivalence among commercial HIV-1 viral load tests, including EasyQ HIV-1 v2.0 (EasyQ) from bioMerieux NucliSens of France; VERSANT HIV-1 RNA 3.0 assay (bDNA) from Siemens Healthcare Diagnostics of USA; COBAS AmpliPrep/COBAS TaqMan HIV-1 test (Taqman) from Roche Molecular Diagnosis of USA; Abbott Real Time HIV-1 Kit (M2000) from Abbott Molecular of USA and two domestic HIV-1 viral load test kits (domestic kit) from DaAn Gene Company of Sun Yat-Sen University and Liaoning Bio-Pharmaceutical company of Northeast pharmaceutical group, by using proficiency test results in China from 2013 to 2015. Methods: A total of 2 954 proficiency test results, obtained from 22 positive samples of 6 proficiency tests in 155 laboratories conducted by China CDC were analyzed during 2013-2015. The results from each sample were first logarithmic transformed and then grouped according to the method used, the mean value of logarithmic results was calculated. Subsequently, 22 clusters of mean values were analyzed by Bland-Altman analysis for the consistency, and linear regression analysis for the interdependency. Results: The results indicated that, by taking Taqman as the reference, EasyQ, M2000, bDNA and domestic kit had good consistency (90%-100%) and interdependency. Conclusion: All the viral load tests were bio-equivalent. Moreover, according to the conversion formula derived from domestic proficiency test results, all the viral load results could be converted, which is critical for epidemiological analysis.
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Affiliation(s)
- L Zhang
- National AIDS/STD Reference Laboratory, National Center for AIDS/STD Control and Prevention
| | - C Jin
- National AIDS/STD Reference Laboratory, National Center for AIDS/STD Control and Prevention
| | - Z Jiang
- Division of Prevention and Intervention, National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - T Tang
- National AIDS/STD Reference Laboratory, National Center for AIDS/STD Control and Prevention
| | - Y Jiang
- National AIDS/STD Reference Laboratory, National Center for AIDS/STD Control and Prevention
| | - P L Pan
- National AIDS/STD Reference Laboratory, National Center for AIDS/STD Control and Prevention
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20
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Jobbágy V, Stroh H, Marissens G, Hult M. Comprehensive study on the technical aspects of sampling, transporting and measuring radon-in-water. J Environ Radioact 2019; 197:30-38. [PMID: 30502660 PMCID: PMC6343077 DOI: 10.1016/j.jenvrad.2018.11.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 11/22/2018] [Accepted: 11/22/2018] [Indexed: 05/25/2023]
Abstract
The European Commission's Joint Research Centre organizes proficiency tests (PT) on radon-in-water measurements. In order to optimize sampling, transport and measurement methods many tests and small scale proficiency tests have been performed. The waters from natural springs, wells were sampled on-site in glass bottles then transported cooled to the JRC and collaborating laboratories. For the material characterization standard measurement methods based on gamma-ray spectrometry, emanometry and liquid scintillation counting were used. The influence of sampling, transport and sample handling on radon-loss was tested and quantified. It was observed that parameters like container material, filling height, storage temperature and handling can lead to substantial measurement bias due to radon-loss. This high risk for radon-loss from samples can potentially be a general radioprotection problem as doses to the public may be underestimated. Regular air and road transport can be considered adequate means of transport as they have little influence on radon-loss if a suitable glass sample container with flexible cap is used and that it is completely filled. On the basis of this work, modifications to the related standard as best practices are also proposed.
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Affiliation(s)
- Viktor Jobbágy
- European Commission, Joint Research Centre (JRC-Geel), Retieseweg 111, B-2440, Geel, Belgium.
| | - Heiko Stroh
- European Commission, Joint Research Centre (JRC-Geel), Retieseweg 111, B-2440, Geel, Belgium
| | - Gerd Marissens
- European Commission, Joint Research Centre (JRC-Geel), Retieseweg 111, B-2440, Geel, Belgium
| | - Mikael Hult
- European Commission, Joint Research Centre (JRC-Geel), Retieseweg 111, B-2440, Geel, Belgium
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21
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Stöckel S, Cordes J, Stoffels B, Wildanger D. Scents in the stack: olfactometric proficiency testing with an emission simulation apparatus. Environ Sci Pollut Res Int 2018; 25:24787-24797. [PMID: 29926329 PMCID: PMC6133125 DOI: 10.1007/s11356-018-2515-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/05/2018] [Indexed: 06/08/2023]
Abstract
Olfactometry is globally acknowledged as a technique to determine odor concentrations, which are used to characterize odors for regulatory purposes, e.g., to protect the general public against harmful effects of air pollution. Although the determination procedure for odor concentrations is standardized in some countries, continued research is required to understand uncertainties of odor monitoring and prediction. In this respect, the present paper strives to provide answers of paramount importance in olfactometry. To do so, a wealth of measurement data originating from six large-scale olfactometric stack emission proficiency tests conducted from 2015 to 2017 was retrospectively analyzed. The tests were hosted at a unique emission simulation apparatus-a replica of an industry chimney with 23 m in height-so that for the first time, conventional proficiency testing (no sampling) with real measurements (no reference concentrations) was combined. Surprisingly, highly variable recovery rates of the odorants were observed-no matter, which of the very different odorants was analyzed. Extended measurement uncertainties with roughly 30-300% up to 20-520% around a single olfactometric measurement value were calculated, which are way beyond the 95% confidence interval given by the widely used standard EN 13725 (45-220%) for assessment and control of odor emissions. Also, no evidence has been found that mixtures of odorants could be determined more precisely than single-component odorants. This is an important argument in the intensely discussed topic, whether n-butanol as current reference substance in olfactometry should be replaced by multi-component odorants. However, based on our data, resorting to an alternative reference substance will not solve the inherent problem of high uncertainty levels in dynamic olfactometry. Finally, robust statistics allowed to calculate reliable odor thresholds, which are an important prerequisite to convert mass concentrations to odor concentrations and vice versa.
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Affiliation(s)
- Stephan Stöckel
- Department I3 (Air Pollution Control, Emission), Hessian Agency for Nature Conservation, Environment and Geology, Kassel, Germany
| | - Jens Cordes
- Department I3 (Air Pollution Control, Emission), Hessian Agency for Nature Conservation, Environment and Geology, Kassel, Germany
| | - Benno Stoffels
- Department I3 (Air Pollution Control, Emission), Hessian Agency for Nature Conservation, Environment and Geology, Kassel, Germany
| | - Dominik Wildanger
- Department I3 (Air Pollution Control, Emission), Hessian Agency for Nature Conservation, Environment and Geology, Kassel, Germany.
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22
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Stadler D, Sulyok M, Schuhmacher R, Berthiller F, Krska R. The contribution of lot-to-lot variation to the measurement uncertainty of an LC-MS-based multi-mycotoxin assay. Anal Bioanal Chem 2018; 410:4409-4418. [PMID: 29713754 PMCID: PMC6021480 DOI: 10.1007/s00216-018-1096-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 04/05/2018] [Accepted: 04/17/2018] [Indexed: 12/02/2022]
Abstract
Multi-mycotoxin determination by LC-MS is commonly based on external solvent-based or matrix-matched calibration and, if necessary, the correction for the method bias. In everyday practice, the method bias (expressed as apparent recovery RA), which may be caused by losses during the recovery process and/or signal/suppression enhancement, is evaluated by replicate analysis of a single spiked lot of a matrix. However, RA may vary for different lots of the same matrix, i.e., lot-to-lot variation, which can result in a higher relative expanded measurement uncertainty (Ur). We applied a straightforward procedure for the calculation of Ur from the within-laboratory reproducibility, which is also called intermediate precision, and the uncertainty of RA (ur,RA). To estimate the contribution of the lot-to-lot variation to Ur, the measurement results of one replicate of seven different lots of figs and maize and seven replicates of a single lot of these matrices, respectively, were used to calculate Ur. The lot-to-lot variation was contributing to ur,RA and thus to Ur for the majority of the 66 evaluated analytes in both figs and maize. The major contributions of the lot-to-lot variation to ur,RA were differences in analyte recovery in figs and relative matrix effects in maize. Ur was estimated from long-term participation in proficiency test schemes with 58%. Provided proper validation, a fit-for-purpose Ur of 50% was proposed for measurement results obtained by an LC-MS-based multi-mycotoxin assay, independent of the concentration of the analytes.
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Affiliation(s)
- David Stadler
- Center for Analytical Chemistry, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Straße 20, 3430, Tulln, Austria
| | - Michael Sulyok
- Center for Analytical Chemistry, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Straße 20, 3430, Tulln, Austria.
| | - Rainer Schuhmacher
- Center for Analytical Chemistry, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Straße 20, 3430, Tulln, Austria
| | - Franz Berthiller
- Center for Analytical Chemistry, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Straße 20, 3430, Tulln, Austria
| | - Rudolf Krska
- Center for Analytical Chemistry, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU), Konrad-Lorenz-Straße 20, 3430, Tulln, Austria
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Thanh TT, Vuong LQ, Ho PL, Chuong HD, Nguyen VH, Tao CV. Validation of an advanced analytical procedure applied to the measurement of environmental radioactivity. J Environ Radioact 2018; 184-185:109-113. [PMID: 29407639 DOI: 10.1016/j.jenvrad.2017.12.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 12/26/2017] [Accepted: 12/30/2017] [Indexed: 06/07/2023]
Abstract
In this work, an advanced analytical procedure was applied to calculate radioactivity in spiked water samples in a close geometry gamma spectroscopy. It included MCNP-CP code in order to calculate the coincidence summing correction factor (CSF). The CSF results were validated by a deterministic method using ETNA code for both p-type HPGe detectors. It showed that a good agreement for both codes. Finally, the validity of the developed procedure was confirmed by a proficiency test to calculate the activities of various radionuclides. The results of the radioactivity measurement with both detectors using the advanced analytical procedure were received the ''Accepted'' statuses following the proficiency test.
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Affiliation(s)
- Tran Thien Thanh
- Department of Nuclear Physics, Faculty of Physics and Engineering Physics, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam; Nuclear Technique Laboratory, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam.
| | - Le Quang Vuong
- Department of Nuclear Physics, Faculty of Physics and Engineering Physics, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam
| | - Phan Long Ho
- Department of Nuclear Physics, Faculty of Physics and Engineering Physics, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam; Department of Testing, Institute of Public Health in Ho Chi Minh City, 159, Hung Phu Street, District 8, Ho Chi Minh City, Vietnam
| | - Huynh Dinh Chuong
- Nuclear Technique Laboratory, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam
| | - Vo Hoang Nguyen
- Department of Nuclear Physics, Faculty of Physics and Engineering Physics, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam
| | - Chau Van Tao
- Department of Nuclear Physics, Faculty of Physics and Engineering Physics, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam; Nuclear Technique Laboratory, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam
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Abstract
Coregulation as a form of risk management relies upon a government-private partnership in regulation using government-backed codes of practice or action plans. In Texas, implementation of coregulation to manage aflatoxin risk has been practiced since 2011 and operates under the program title One Sample Strategy (OSS). Aflatoxin-contaminated cereals and oilseeds that contain greater than 20 μg/kg of the toxin (B1, B2, G1, and G2) are adulterated as defined by the Texas Commercial Feed Rules and regulated by the Texas Feed and Fertilizer Control Service of the Office of the Texas State Chemist. The present study was intended to evaluate the implementation and effectiveness of the coregulation program for 3 years based on selected evaluation criteria aiming to improve aflatoxin risk management and thus reduce market and food safety risk in Texas. In 2013, 124 analysts qualified to participate in the program at 23 grain elevators. During the 2013 harvest, use of control samples to ensure testing accuracy revealed that the average relative standard deviation among all participants was 14.5%. In 2014 and 2015, 129 and 151 analysts, respectively, qualified to measure aflatoxin, and the average relative standard deviation values for the working control across the 29 and 30 participating firms were 16.2 and 13.7%, respectively. All firms demonstrated the capability to grind maize to the OSS-prescribed particle size (70% passing through a 20-mesh sieve) in all 3 years. The Texas Feed and Fertilizer Control Service verified testing accuracy of OSS participants analyzing 612, 693, and 482 retained samples in 2013, 2014, and 2015, respectively. Results were plotted in an operating curve to depict type I and type II errors. The implementation of the OSS built upon a quality system-based code of practice successfully managed aflatoxin risk in Texas by using coregulation as a governance option.
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Affiliation(s)
- Mary Sasser
- Office of the Texas State Chemist, Texas A&M AgriLife Research, Texas A&M University System, College Station, Texas 77841, USA
| | - Timothy J Herrman
- Office of the Texas State Chemist, Texas A&M AgriLife Research, Texas A&M University System, College Station, Texas 77841, USA
| | - Kyung-Min Lee
- Office of the Texas State Chemist, Texas A&M AgriLife Research, Texas A&M University System, College Station, Texas 77841, USA
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25
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Ferreira KM, Fenwick AJ. 123I intercomparison exercises: Assessment of measurement capabilities in UK hospitals. Appl Radiat Isot 2017; 134:108-111. [PMID: 29249627 DOI: 10.1016/j.apradiso.2017.11.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 11/11/2017] [Accepted: 11/11/2017] [Indexed: 11/25/2022]
Abstract
Three comparison exercises have been performed in 1996, 1999 and 2015 with 123I to assess the UK hospitals measurement capabilities using radionuclide calibrators for this particular radionuclide. The exercise performed in 1996 showed that only 62% of the participants could measure the solution to within 10% of the standardised value and only 28% could measure within 5% of the certificated value. The intercomparison exercise performed in 1999 showed no improvement in the measurement capability, with only 66% of the participants measuring to within 10% of the standardised value. The exercise performed in 2015 showed great improvement in the hospitals measurement capability, 94% of participants reported results within 10% of the certificated activity and 85% of the participants reported results within the 5% of the reported activity. The intercomparison exercises are an important way to identify possible measurement problems within the medical community. Additionally, the intercomparison exercises provide hospitals with traceability to national primary standards and improve measurement capability within the Nuclear Medicine community.
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Affiliation(s)
| | - Andrew J Fenwick
- National Physical Laboratory, Teddington TW11 0LW, United Kingdom
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26
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Choi Y, Lee S, Kwon SY, Lee Y, Park YK, Ban SJ. Analysis of the proficiency of single radial immunodiffusion assays for quality control of influenza vaccines in Korea. Biologicals 2017; 50:137-140. [PMID: 29111376 DOI: 10.1016/j.biologicals.2017.08.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 07/28/2017] [Accepted: 08/01/2017] [Indexed: 11/17/2022] Open
Abstract
Influenza vaccine potency, which is determined by quantitatively measuring the content of Hemagglutinin (HA), is an essential index representing the efficacy of the vaccine. Standardization of the single radial immunodiffusion (SRID) assay, a method for measuring HA content, and proficiency of the testing institutions are crucial for influenza vaccine quality control. Herein, we assessed the proficiency of SRID assays at the National Control Laboratory (NCL) of Korea and several vaccine manufacturers. Eight laboratories participated in this study, and the proficiencies of all laboratories yielded satisfactory results in overall SRID assays. In contrast, there were some unsatisfactory results in measuring with different types of agarose gel plates produced by other laboratories. Overall, our findings demonstrated that the proficiency of SRID assay in the tested laboratories is acceptable for quality control of influenza vaccines and that detailed review on the validation reports regarding the test methods will be helpful for better control.
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Affiliation(s)
- Yejin Choi
- Vaccines Division, National Institute of Food and Drug Safety Evaluation, 187 Osongsaengmyeoung 2-ro, Osong-eup, Heungdoek-gu, Cheongju 28159, Republic of Korea; Department of Biochemistry, College of Natural Science, Chungbuk National University, Cheongju 28644, Republic of Korea
| | - Sunmi Lee
- Vaccines Division, National Institute of Food and Drug Safety Evaluation, 187 Osongsaengmyeoung 2-ro, Osong-eup, Heungdoek-gu, Cheongju 28159, Republic of Korea; School of Life Sciences and Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Seong Yi Kwon
- Vaccines Division, National Institute of Food and Drug Safety Evaluation, 187 Osongsaengmyeoung 2-ro, Osong-eup, Heungdoek-gu, Cheongju 28159, Republic of Korea
| | - Younghee Lee
- Department of Biochemistry, College of Natural Science, Chungbuk National University, Cheongju 28644, Republic of Korea
| | - Yong Keun Park
- School of Life Sciences and Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Sang Ja Ban
- Vaccines Division, National Institute of Food and Drug Safety Evaluation, 187 Osongsaengmyeoung 2-ro, Osong-eup, Heungdoek-gu, Cheongju 28159, Republic of Korea.
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Dill V, Eschbaumer M, Beer M, Hoffmann B. Inter-laboratory validation of foot-and-mouth disease diagnostic capability in Germany. Vet Microbiol 2017; 203:62-67. [PMID: 28619169 DOI: 10.1016/j.vetmic.2017.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 02/28/2017] [Accepted: 03/01/2017] [Indexed: 11/25/2022]
Abstract
Germany has been free from foot-and-mouth disease virus (FMDV) without vaccination since 1992, but diagnostic capability at regional laboratories is maintained for FMDV exclusion in suspect cases and as surge capacity for outbreak preparedness. A proficiency test was initiated in 2015 to evaluate the diagnostic performance of 20 regional veterinary laboratories. A panel of two identical samples of FMDV genome for real-time reverse transcription polymerase chain reaction (RT-PCR), four lyophilized bovine sera for antibody detection and eight samples of inactivated vaccine antigen for analysis with a lateral-flow device (LFD) were tested with the systems routinely used at the participating institutions. With only one exception, all laboratories reliably detected viral RNA with two real-time RT-PCR assays down to a dilution of 10(-4) of the original material. The LFD pen-side test was evaluated at 8 of 20 laboratories, and FMDV antigen was detected by all participants down to a dilution of 1:81. Serological diagnosis was also very consistent at most participating institutions. Very few false-negative results were returned for the diluted positive sera, and testing of a large cohort of negative samples demonstrated a high specificity of over 99% for the two commercial ELISA kits used (PrioCHECK® FMDV NS and ID Screen® FMD NSP). In conclusion, the proficiency test demonstrated the reliable and robust FMDV diagnostic capability of the German regional veterinary diagnostic laboratories. Furthermore, the suitability of the commercially available ELISA systems for the detection of FMDV-specific antibodies was confirmed. Proficiency tests are an important quality assurance measure for transboundary diseases like FMDV where diagnostic capacity in free countries has to be available at the highest possible standard.
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Affiliation(s)
- Veronika Dill
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald-Insel Riems, Germany
| | - Michael Eschbaumer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald-Insel Riems, Germany.
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald-Insel Riems, Germany
| | - Bernd Hoffmann
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald-Insel Riems, Germany
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Abstract
Explosives residues are often collected from explosion scenes, and from surfaces suspected of being in contact with explosives, by swabbing with solvent-wetted cotton swabs. It is vital that any explosives traces present on the swabs are successfully extracted and detected when received in a laboratory. However, a 2007 proficiency test initiated by the European Network of Forensic Science Institutes (ENFSI) Expert Working Group on Explosives involving TNT-spiked cotton swabs highlighted that explosives may not always be detected from such samples. This paper outlines work performed to determine potential reasons for this finding. Cotton swabs were spiked using a solution of TNT and stored in nylon bags and glass vials for periods of 1, 2 and 4weeks. Simulated swab extracts were also prepared and investigated. The samples were stored in a freezer, or at room temperature either in the dark or exposed to daylight. Overall, the cotton swabs stored at room temperature and exposed to daylight showed a very rapid loss of TNT over time, whereas cotton swabs stored in the freezer, and all simulated swab extracts, gave high recoveries over time. These results will be of benefit for practicing forensic explosives laboratories and for persons undertaking cold-case reviews involving explosive-based samples.
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Affiliation(s)
- Niamh Nic Daeid
- Centre for Anatomy and Human Identification, School of Science and Engineering, University of Dundee, Dow Street, Dundee DD1 5EH, UK.
| | - Holly A Yu
- Centre for Anatomy and Human Identification, School of Science and Engineering, University of Dundee, Dow Street, Dundee DD1 5EH, UK; Department of Chemistry, Curtin University, GPO Box U1987, Perth, WA 6845, Australia
| | - Matthew S Beardah
- Defence Science and Technology Laboratory (Dstl), Fort Halstead, Sevenoaks, Kent TN14 7BP, UK
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29
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Hung NQ, Chuong HD, Vuong LQ, Thanh TT, Tao CV. Intercomparison NaI(Tl) and HPGe spectrometry to studies of natural radioactivity on geological samples. J Environ Radioact 2016; 164:197-201. [PMID: 27500857 DOI: 10.1016/j.jenvrad.2016.07.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 07/29/2016] [Accepted: 07/30/2016] [Indexed: 06/06/2023]
Abstract
In this study, in situ gamma spectra using NaI(Tl) detector have been compared with the laboratory measurements by using HPGe detector on geological samples. The results for measuring naturally occurring terrestrial gamma radiation of 40K and the decay series of 232Th and, 238U respectively of both detectors show a maximum deviation about 5%. The mass activities series from both detectors were checked for coherence using proficiency test procedure from the International Atomic Energy Agency. The reliability and precision pass for final scores for all the analytical determinations of are received "acceptable" for all radionuclides.
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Affiliation(s)
- Nguyen Quoc Hung
- Department of Nuclear Physics, Faculty of Physics and Engineering Physics, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam; Nuclear Technique Laboratory, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam
| | - Huynh Dinh Chuong
- Nuclear Technique Laboratory, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam
| | - Le Quang Vuong
- Department of Nuclear Physics, Faculty of Physics and Engineering Physics, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam
| | - Tran Thien Thanh
- Department of Nuclear Physics, Faculty of Physics and Engineering Physics, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam; Nuclear Technique Laboratory, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam.
| | - Chau Van Tao
- Department of Nuclear Physics, Faculty of Physics and Engineering Physics, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam; Nuclear Technique Laboratory, VNUHCM-University of Science, 227, Nguyen Van Cu Street, District 5, Ho Chi Minh City, Viet Nam
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30
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Dehouck P, Cordeiro F, Snell J, de la Calle B. State of the art in the determination of trace elements in seawater: a worldwide proficiency test. Anal Bioanal Chem 2016; 408:3223-32. [PMID: 26886745 PMCID: PMC4830889 DOI: 10.1007/s00216-016-9390-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 01/28/2016] [Accepted: 02/02/2016] [Indexed: 12/05/2022]
Abstract
This manuscript presents the results of the International Measurement Evaluation Programme 40 (IMEP-40) study, a proficiency test (PT) which was organised to assess the worldwide performance of laboratories for the determination of trace elements in seawater. This PT supports the implementation of the European Union Water Framework Directive 2000/60/EC, which aims at achieving a long-term high level protection of the aquatic environment, covering lakes, ground water and coastal waters. Forty-six participants reported results. The test item was seawater containing the trace elements As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Se and Zn. The trace elements in the test item were present in very low concentrations to mimic natural levels. The results of the participants were rated with z and zeta (ζ) scores in accordance with ISO 13528 and ISO 17043. The standard deviation for proficiency assessment, \documentclass[12pt]{minimal}
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\begin{document}$$ \widehat{\upsigma} $$\end{document}σ^, was set at 25 % of the respective assigned values for the 12 measured elements based on previous experience with similar PTs. The low levels of the trace elements combined with the high salt concentration of the seawater made the measurements challenging. Many laboratories were unable to detect or quantify the elements and reported “lower than X” values. The percentage of satisfactory performances (expressed as z scores) ranged from 41 % (Cr, Fe) to 86 % (Mo). The PT study showed that the use of proper standard methods, like ISO 17294-2, and sensitive techniques, like inductively coupled plasma mass spectrometry (ICP-MS), contributed to performing well in this PT round.
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Affiliation(s)
- Pieter Dehouck
- European Commission, Directorate General Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, 2440, Geel, Belgium.
| | - Fernando Cordeiro
- European Commission, Directorate General Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, 2440, Geel, Belgium
| | - James Snell
- European Commission, Directorate General Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, 2440, Geel, Belgium
| | - Beatriz de la Calle
- European Commission, Directorate General Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, 2440, Geel, Belgium
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31
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Jacobsen S, Patel P, Schmidt-Chanasit J, Leparc-Goffart I, Teichmann A, Zeller H, Niedrig M. External quality assessment studies for laboratory performance of molecular and serological diagnosis of Chikungunya virus infection. J Clin Virol 2016; 76:55-65. [PMID: 26828561 DOI: 10.1016/j.jcv.2016.01.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/10/2016] [Indexed: 10/22/2022]
Abstract
BACKGROUND Since the re-emergence of Chikungunya virus (CHIKV) in Reunion in 2005 and the recent outbreak in the Caribbean islands with an expansion to the Americas the CHIK diagnostic became very important. OBJECTIVES We evaluate the performance of laboratories regarding molecular and serological diagnostic of CHIK worldwide. STUDY DESIGN A panel of 12 samples for molecular and 13 samples for serology were provided to 60 laboratories in 40 countries for evaluating the sensitivity and specificity of molecular and serology testing. RESULTS The panel for molecular diagnostic testing was analysed by 56 laboratories returning 60 data sets of results whereas the 56 and 60 data sets were returned for IgG and IgM diagnostic from the participating laboratories. Twenty-three from 60 data sets performed optimal, 7 acceptable and 30 sets of results require improvement. From 50 data sets only one laboratory shows an optimal performance for IgM detection, followed by 9 data sets with acceptable and the rest need for improvement. From 46 IgG serology data sets 20 provide an optimal, 2 an acceptable and 24 require improvement performance. The evaluation of some of the diagnostic performances allows linking the quality of results to the in-house methods or commercial assays used. CONCLUSION The external quality assurance for CHIK diagnostics provides a good overview on the laboratory performance regarding sensitivity and specificity for the molecular and serology diagnostic required for the quick and reliable analysis of suspected CHIK patients. Nearly half of the laboratories have to improve their diagnostic profile to achieve a better performance.
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Affiliation(s)
- Sonja Jacobsen
- Centre for Biological Threats and Special Pathogens, Highly Pathogenic Viruses, Robert Koch Institute, Berlin, Germany
| | - Pranav Patel
- Centre for Biological Threats and Special Pathogens, Highly Pathogenic Viruses, Robert Koch Institute, Berlin, Germany
| | - Jonas Schmidt-Chanasit
- WHO Collaborating Centre for Arbovirus and Haemorrhagic Fever Reference and Research, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | | | - Anette Teichmann
- Centre for Biological Threats and Special Pathogens, Highly Pathogenic Viruses, Robert Koch Institute, Berlin, Germany
| | - Herve Zeller
- European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
| | - Matthias Niedrig
- Centre for Biological Threats and Special Pathogens, Highly Pathogenic Viruses, Robert Koch Institute, Berlin, Germany.
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Visetpotjanakit S, Kaewpaluek S, Udomsomporn S. Participation in IAEA-TEL-201304/28 ALMERA Proficiency Test Exercise on Determination of Anthropogenic Radionuclides in Water and Flour Samples. Appl Radiat Isot 2015; 109:78-81. [PMID: 26688353 DOI: 10.1016/j.apradiso.2015.11.045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 11/19/2015] [Indexed: 11/26/2022]
Abstract
The Office of Atoms for Peace (OAP) participated in the IAEA-TEL-201304/28 ALMERA Proficiency Test Exercise, "Determination of Anthropogenic Radionuclides in Water and Flour Samples," organized by the ALMERA network. There were three test samples sent together with one known activity sample for quality control purpose. Two of the test samples were spiked water: one contained (134)Cs and (137)Cs and the other contained (90)Sr, (60)Co, (152)Eu and (241)Am. The third sample was wheat flour spiked with (134)Cs and (137)Cs. OAP submitted all results to IAEA after determining (134)Cs, (137)Cs, (60)Co, (152)Eu and (241)Am activities by direct gamma-ray counting and (90)Sr by chemical separation and Cerenkov measurement. Our results with critical comments and statistical analysis are described in this paper.
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Affiliation(s)
- S Visetpotjanakit
- Radiation Monitoring Group, Bureau of Technical Support for Safety Regulation, Office of Atoms for Peace, Thailand.
| | - S Kaewpaluek
- Radiation Monitoring Group, Bureau of Technical Support for Safety Regulation, Office of Atoms for Peace, Thailand
| | - S Udomsomporn
- Radiation Monitoring Group, Bureau of Technical Support for Safety Regulation, Office of Atoms for Peace, Thailand
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Hanon JB, Vandenberge V, Deruelle M, De Leeuw I, De Clercq K, Van Borm S, Koenen F, Liu L, Hoffmann B, Batten CA, Zientara S, Breard E, Van der Stede Y. Inter-laboratory evaluation of the performance parameters of a Lateral Flow Test device for the detection of Bluetongue virus-specific antibodies. J Virol Methods 2015; 228:140-50. [PMID: 26687976 DOI: 10.1016/j.jviromet.2015.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 11/23/2015] [Accepted: 12/01/2015] [Indexed: 12/01/2022]
Abstract
Bluetongue (BT) is a viral vector-borne disease affecting domestic and wild ruminants worldwide. In this study, a commercial rapid immuno-chromatographic method or Lateral Flow Test (LFT) device, for the detection of BT virus-specific antibodies in animal serum, was evaluated in an international inter-laboratory proficiency test. The evaluation was done with sera samples of variable background (ruminant species, serotype, field samples, experimental infections, vaccinated animals). The diagnostic sensitivity was 100% (95% C.I. [90.5-100]) and the diagnostic specificity was 95.2% (95% C.I. [76.2-99.9]). The repeatability (accordance) and reproducibility (concordance) were 100% for seropositive samples but were lower for two of the seronegative samples (45% and 89% respectively). The analytical sensitivity, evaluated by testing positive sera at increasing dilutions was better for the BT LFT compared to some commercial ELISAs. Seroconversion of an infected sheep was detected at 4 days post infection. Analytical specificity was impaired by cross-reactions observed with some of the samples seropositive for Epizootic Haemorrhagic Disease Virus (EHDV). The agreement (Cohen's kappa) between the LFT and a commercial BT competitive ELISA was 0.79 (95% CI [0.62-0.95]). Based on these results, it can be concluded that the BT LFT device is a rapid and sensitive first-line serological test that can be used in the field, especially in areas endemic for the disease where there is a lack of diagnostic facilities.
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Affiliation(s)
- Jean-Baptiste Hanon
- Veterinary and Agrochemical Research Centre (CODA-CERVA), Coordination of the Veterinary Diagnostic, Epidemiology and Risk Analysis Unit (CDV-ERA), Groeselenberg 99, 1180 Brussels, Belgium.
| | - Valerie Vandenberge
- Veterinary and Agrochemical Research Centre (CODA-CERVA), Coordination of the Veterinary Diagnostic, Epidemiology and Risk Analysis Unit (CDV-ERA), Groeselenberg 99, 1180 Brussels, Belgium
| | - Matthias Deruelle
- Veterinary and Agrochemical Research Centre (CODA-CERVA), Coordination of the Veterinary Diagnostic, Epidemiology and Risk Analysis Unit (CDV-ERA), Groeselenberg 99, 1180 Brussels, Belgium
| | - Ilse De Leeuw
- Veterinary and Agrochemical Research Centre (CODA-CERVA), Vesicular and Exotic Diseases Unit, National Reference Laboratory for Bluetongue, Groeselenberg 99, 1180 Brussels, Belgium
| | - Kris De Clercq
- Veterinary and Agrochemical Research Centre (CODA-CERVA), Vesicular and Exotic Diseases Unit, National Reference Laboratory for Bluetongue, Groeselenberg 99, 1180 Brussels, Belgium
| | - Steven Van Borm
- Veterinary and Agrochemical Research Centre (CODA-CERVA), Molecular Platform Unit, Groeselenberg 99, 1180 Brussels, Belgium
| | - Frank Koenen
- Veterinary and Agrochemical Research Centre (CODA-CERVA), Coordination of the Veterinary Diagnostic, Epidemiology and Risk Analysis Unit (CDV-ERA), Groeselenberg 99, 1180 Brussels, Belgium
| | - Lihong Liu
- National Veterinary Institute (SVA), Department of Virology, Immunobiology and Parasitology (VIP), SE-751 89 Uppsala, Sweden
| | - Bernd Hoffmann
- Friedrich-Loeffler-Institut (FLI), Institute of Diagnostic Virology, Südufer 10, 17493 Greifswald-Insel Riems, Germany
| | - Carrie Anne Batten
- The Pirbright Institute, Non Vesicular Reference Laboratory, Ash Road, Pirbright, Woking GU240NF, United Kingdom
| | - Stéphan Zientara
- Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES), UPE, UMR Anses, INRA, ENVA, 14 rue Pierre et Marie Curie, laboratoire de santé animale, Maisons-Alfort, France
| | - Emmanuel Breard
- Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES), UPE, UMR Anses, INRA, ENVA, 14 rue Pierre et Marie Curie, laboratoire de santé animale, Maisons-Alfort, France
| | - Yves Van der Stede
- Veterinary and Agrochemical Research Centre (CODA-CERVA), Coordination of the Veterinary Diagnostic, Epidemiology and Risk Analysis Unit (CDV-ERA), Groeselenberg 99, 1180 Brussels, Belgium; Ghent University, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Salisburylaan 133, 9820 Merelbeke, Belgium
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Kerkhoff W, Stoel RD, Berger CE, Mattijssen EJ, Hermsen R, Smits N, Hardy HJ. Design and results of an exploratory double blind testing program in firearms examination. Sci Justice 2015; 55:514-9. [PMID: 26654088 DOI: 10.1016/j.scijus.2015.06.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 06/08/2015] [Accepted: 06/12/2015] [Indexed: 11/23/2022]
Abstract
In 2010, the Netherlands Forensic Institute (NFI) and the University of Amsterdam (UvA) started a series of tests for the NFI's Firearms Section. Ten cartridge case and bullet comparison tests were submitted by various external parties as regular cases and mixed in the flow of real cases. The results of the tests were evaluated with the VU University Amsterdam (VUA). A total of twenty-nine conclusions were drawn in the ten tests. For nineteen conclusions the submitted cartridge cases or bullets were either fired from the questioned firearm or from one and the same firearm, in tests where no firearm was submitted. For ten conclusions the submitted cartridge cases or bullets were either fired from another firearm than the submitted one or from several firearms, in tests where no firearm was submitted. In none of the conclusions misleading evidence was reported, in the sense that all conclusions supported the true hypothesis. This article discusses the design considerations of the program, contains details of the tests, and describes the various ways the test results were and could be analyzed.
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Sykes M, Croucher J, Smith RA. Resolution of vitamin A cis/trans isomers resolves proficiency test assessments. Food Chem 2013; 141:1597-602. [PMID: 23870865 DOI: 10.1016/j.foodchem.2013.05.086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 05/03/2013] [Accepted: 05/16/2013] [Indexed: 11/18/2022]
Abstract
Proficiency tests run by FAPAS for vitamin A analysis in cod liver oil were observed to give rise to multi-modal distributions of data. For this reason, setting the assigned value for the tests was difficult or even impossible, without too high uncertainty values. The methods used by participants could broadly be categorised into normal phase or reversed-phase high performance liquid chromatography. In a recent test, participants were asked if their method could separate the cis and trans isomers of vitamin A. Results from participants who could separate the isomers gave rise to a unimodal distribution of data. This was synonymous with participants using the normal phase chromatography method. Conversely, results from participants who were unable to separate the isomers, or who were using reversed-phase chromatography, gave rise to multi-modal distributions of data. The recommendation for future tests is to set the assigned value on the basis of the ability to separate the isomers.
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Affiliation(s)
- Mark Sykes
- The Food and Environment Research Agency, Sand Hutton, York YO41 1LZ, UK.
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