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The environmental impact assessment of materials is usually based on laboratory tests, mostly in combination with models describing the longterm fate of the substances of interest in the targeted environmental compartment. Thus, laboratory tests are the fundamental link to achieve appropriate assessment conclusions which makes it essential to generate consistent results. This just as applies to the leaching of cementitious materials. In Europe, the leaching behavior of monolithic building materials is tested in the Dynamic Surface Leaching Test following the specification CEN/TS 16637-2. An interlaboratory comparison on European level regarding this technical specification showed relatively high intra- and interlaboratory variations for the tested materials (monolithic copper slag and cement stabilized coal fly ash). Therefore the German Committee for Structural Concrete (DAfStb) framed a guideline to specify additional testing conditions for cementitious materials. To assess the possible improvement by this guidelines measures, a round robin test with 11 participants from Germany and the Netherlands was conducted. This work aims to provide insight into the factors to be considered in the testing of alkaline materials, including sample preparation, and highlights crucial procedures and their manifestation in the results. All evaluated parameters showed improved results compared to the earlier round robin test. The relative standard deviations for repeatability (RSDr) and reproducibility (RSDR) of the elements calcium, barium, antimony, chromium, molybdenum and vanadium, which are the parameters evaluated in both round robin tests, were RSDr = 4%, 4%, 2%, 5%, 5%, and 5% respectively (4% in average) for this work, in comparison to the European round robin test with an average RSDr of 29% (17%, 17%, 20%, 40%, 36%, and 42%). The RSDR improved from 41% (30%, 36%, 29%, 57%, 40%, and 56%) to 14% (12%, 8%, 6%, 28%, 15%, and 12%). CO2 ingress during testing and the inaccuracy of eluate analytics for concentrations close to the determination limits were identified as the main sources of error.
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Ceniza del Carbón , Materiales de Construcción , Cromo , Cobre , Humanos , Reproducibilidad de los ResultadosRESUMEN
Round robin testing is an important instrument for quality assurance. Increasingly, this also applies to the results of molecular diagnostics in pathology, which directly influence therapy decisions in precision oncology. In metastatic colorectal carcinoma (mCRC), the focus has been on detecting KRAS and NRAS mutations, whose absence allows therapy with EGFR blocking antibodies. Recently, BRAF has been added as another predictive marker, since mCRC patients with BRAF V600E mutation benefit significantly from treatment with encorafenib (a BRAF inhibitor) in combination with cetuximab (anti-EGFR antibody) after systemic therapy. Due to the approval of this treatment in 2020, it is a pre-requisite that BRAF V600E mutation detection in diagnostic pathologies is reliably performed. Therefore, this round robin test with BRAF V600E testing either by immunohistochemistry or molecular methods was performed. The round robin test results demonstrate that molecular BRAF V600E detection is currently clearly superior to immunohistochemical detection.
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Neoplasias Colorrectales , Proteínas Proto-Oncogénicas B-raf , Anticuerpos Monoclonales , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Humanos , Mutación/genética , Medicina de Precisión , Proteínas Proto-Oncogénicas B-raf/genéticaRESUMEN
Emission testing of volatile organic compounds (VOC) from materials and products is commonly based on emission test chamber measurements. To ensure the comparability of results from different testing laboratories, their measurement performance must be verified. For this purpose, Bundesanstalt für Materialforschung und -prüfung (BAM) organizes an international proficiency test (round robin test, RRT) every two years using well-characterized test materials (one sealant, one furniture board, and four times a lacquer) with defined VOC emissions. The materials fulfilled the requirements of homogeneity, reproducibility, and stability. Altogether, 36 VOCs were included of which 33 gave test chamber air concentrations between 13 and 83 µg/m3 . This is the typical concentration range to be expected and to be quantified when performing chamber tests. Three compounds had higher concentrations between 326 and 1105 µg/m3 . In this paper, the relative standard deviations (RSD) of BAM round robin tests since 2008 are compared and the improvement of the comparability of the emission chamber testing is shown by the decrease of the mean RSD down to 28% in 2018. In contrast, the first large European interlaboratory comparison in 1999 showed a mean RSD of 51%.
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Contaminación del Aire Interior , Compuestos Orgánicos Volátiles , Contaminación del Aire Interior/análisis , Materiales de Construcción , Monitoreo del Ambiente , Reproducibilidad de los Resultados , Compuestos Orgánicos Volátiles/análisisRESUMEN
Development and commercialization of self-healing concrete is hampered due to a lack of standardized test methods. Six inter-laboratory testing programs are being executed by the EU COST action SARCOS, each focusing on test methods for a specific self-healing technique. This paper reports on the comparison of tests for mortar and concrete specimens with polyurethane encapsulated in glass macrocapsules. First, the pre-cracking method was analysed: mortar specimens were cracked in a three-point bending test followed by an active crack width control technique to restrain the crack width up to a predefined value, while the concrete specimens were cracked in a three-point bending setup with a displacement-controlled loading system. Microscopic measurements showed that with the application of the active control technique almost all crack widths were within a narrow predefined range. Conversely, for the concrete specimens the variation on the crack width was higher. After pre-cracking, the self-healing effect was characterized via durability tests: the mortar specimens were tested in a water permeability test and the spread of the healing agent on the crack surfaces was determined, while the concrete specimens were subjected to two capillary water absorption tests, executed with a different type of waterproofing applied on the zone around the crack. The quality of the waterproofing was found to be important, as different results were obtained in each absorption test. For the permeability test, 4 out of 6 labs obtained a comparable flow rate for the reference specimens, yet all 6 labs obtained comparable sealing efficiencies, highlighting the potential for further standardization.
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In this study, the results from a round-robin test of hyperspectral imaging systems are presented and analyzed. Fourteen different pushbroom hyperspectral systems from eight different institutions were used to acquire spectral cubes from the visible, near infra-red and short-wave infra-red regions. Each system was used to acquire a common set of targets under their normal operating conditions with the data calibrated and processed using the standard processing pipeline for each system. The test targets consisted of a spectral wavelength standard and of a custom-made pigment panel featuring Renaissance-era pigments frequently found in paintings from that period. The quality and accuracy of the resulting data was assessed with quantitative analyses of the spectral, spatial and colorimetric accuracy of the data. The results provide a valuable insight into the accuracy, reproducibility and precision of hyperspectral imaging equipment when used under routine operating conditions. The distribution and type of error found within the data can provide useful information on the fundamental and practical limits of such equipment when used for applications such as spectral classification, change detection, colorimetry and others.
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BACKGROUND: The present study contrasts the accuracy of different reconstructed models with distinctive segmentation methods performed by various experts. Seven research groups reconstructed nine 3D models of one human femur based on an acquired CT image using their own computational methods. As a reference model for accuracy assessment, a 3D surface scan of the human femur was created using an optical measuring system. Prior to comparison, the femur was divided into four areas; "neck and greater trochanter", "proximal metaphysis", "diaphysis", and "distal metaphysis". The deviation analysis was carried out in GEOMAGIC studio v.2013 software. RESULTS: The results revealed that the highest deviation errors occurred in "neck and greater trochanter" area and "proximal metaphysis" area with RMSE of 0.84 and 0.83 mm respectively. CONCLUSION: In conclusion, this study shows that the average deviation of reconstructed models prepared by experts with various methods, skills and software from the surface 3D scan is lower than 0.79 mm, which is not a significant discrepancy.
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Fémur/diagnóstico por imagen , Imagenología Tridimensional , Laboratorios , Fenómenos Ópticos , Tomografía Computarizada por Rayos X/instrumentación , Tomografía Computarizada por Rayos X/normas , Humanos , Persona de Mediana Edad , Estándares de ReferenciaRESUMEN
Emission testing of products is currently a rapidly increasing field of measurement activity. Labeling procedures for construction products are based on such emission test chamber measurements, and hence, measurement performance should be verified. One possible route is to conduct testing of one material in different laboratories within a round robin test (RRT), ideally using homogeneous reference materials, which can be used within interlaboratory studies or as part of the quality management system to ensure comparable results. The applicability of a lacquer system with nine added VOCs (hexanal, styrene, n-decane, limonene, 2-ethyl-1-hexanol, N-methyl-α-pyrrolidone, 2-ethylhexyl acrylate, dimethyl phthalate, and n-hexadecane) was evaluated in an international RRT with 55 participating laboratories. An intralaboratory quality check confirmed the homogeneity and reproducibility of the lacquer material for most of the compounds (RSD 5%-6%), which was confirmed in the RRT. However, emissions varied for the polar compound N-methyl-α-pyrrolidone and the higher boiling compounds 1,2-dimethyl phthalate, and n-hexadecane which could be traced back to analytical issues. In the RRT, the interlaboratory relative standard deviations (RSDs) ranged from 30% to 65% for all participants but for reference laboratories the range was between 20% and 45%.
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Materiales de Construcción/análisis , Ensayo de Materiales , Compuestos Orgánicos Volátiles/normas , Aire/análisis , Estándares de Referencia , Compuestos Orgánicos Volátiles/análisis , VolatilizaciónRESUMEN
Intrahepatic cholangiocarcinoma harbours druggable genetic lesions including FGFR2 gene fusions. Reliable and accurate detection of these fusions is becoming a critical component of the molecular work-up, but real-world data on the performance of fluorescence in situ hybridisation (FISH) and targeted RNA-based next-generation sequencing (NGS) are very limited. Bridging this gap, we report results of the first round robin test for FGFR2 fusions in cholangiocarcinoma and contextualise test data with genomic architecture. A cohort of 10 cholangiocarcinoma (4 fusion positive and 6 fusion negative) was tested by the Institute of Pathology, University Hospital Heidelberg, Germany. Data were validated by four academic pathology departments in Germany. Fusion-positive cases comprised FGFR2::BICC1, FGFR2::DBP, FGFR2::TRIM8, and FGFR2::ATE1 fusions. In a second step, a round robin test involving 21 academic and non-academic centres testing with RNA-based NGS approaches was carried out; five participants performed FISH testing in addition. Thirteen of 16 (81%) centres successfully passed the NGS only and 3 of 5 (60%) centres passed the combined NGS + FISH round robin test. Identified obstacles were bioinformatic pipelines not optimised for the detection of FGFR2 fusions and assays not capable of detecting unknown fusion partners. This study shows the benefit of targeted RNA-NGS for the detection of FGFR2 gene fusions. Due to the marked heterogeneity of the genomic architecture of these fusions, fusion partner agnostic (i.e. open) methodological approaches that are capable of identifying yet unknown fusion partners are superior. Furthermore, we highlight pitfalls in subsequent bioinformatic analysis and limitations of FISH-based tests.
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Neoplasias de los Conductos Biliares , Colangiocarcinoma , Humanos , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/genética , Fusión Génica , Conductos Biliares Intrahepáticos/patología , Neoplasias de los Conductos Biliares/diagnóstico , Neoplasias de los Conductos Biliares/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Proteínas Portadoras/genética , Proteínas del Tejido Nervioso/genética , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genéticaRESUMEN
BACKGROUND: A medication review aims at the optimization of medication use, the detection of drug-related problems (DRPs) and the recommendation of interventions. As part of the pilot project "Arzneimittelinitiative Sachsen-Thüringen" (ARMIN) and caused by the introduction of several training programs, numerous public pharmacies in Germany currently offer medication reviews for patients. However, a standardized method for external quality control has so far not been established. METHODS: A round robin test for medication reviews was designed in written form by five pharmacists with expertise in different areas (Drug information service ARMIN, Saxonian Chamber of pharmacists, public pharmacy, hospital pharmacy), based on the recommendations of the guideline for medication reviews of the German Federal Chamber of Pharmacists (Bundesapothekerkammer). On the basis of a fictitious case study the participants were asked to check a patient's medication data for the presence of DRPs, propose possible solutions and generate a medication plan. The solutions were assessed by two pharmacists of the drug information service ARMIN on the basis of a best practice solution that had been consented in the study group beforehand. RESULTS: 102 pharmacists and 13 pharmacy students in internship took part in the round robin test. On average, participants achieved a score of 7,62 out of 9 for recognizing DRPs and recommending solutions and a score of 0,79 out of 1 for generating a correct medication plan. 106 participants (92%) met the requirements for successful participation (recognizing the three most relevant DRPs and at least one further DRP as well as generating an adequate medication plan). The implementation of the approach described here proved to be practicable The State Directorate of Saxony accepted the round robin test as a measure for external quality assessment in accordance with legal requirements. CONCLUSIONS: Due to the nationwide introduction of medication reviews as a pharmaceutical service in June 2022, medication reviews performed by German community pharmacies will gain in importance in the coming years. This is why quality assurance is necessary. Since the participants' performance in medication analysis becomes comparable by completing the round robin test, this instrument appears to be potentially suitable for the external quality assessment of medications reviews nationwide.
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Revisión de Medicamentos , Farmacias , Humanos , Armina , Alemania , Proyectos PilotoRESUMEN
Histomorpholgy is one of the mainstays of acute Graft-versus-host disease (GvHD) diagnosis. However, concerns about reproducibility and the most appropriate grading system question its usefulness. Our aim was to assess histomorphological parameters and previously reported grading systems for GvHD regarding reproducibility and validity. Moreover, we propose that sum scores, derived by combining separately scored morphological parameters into a total score, might provide a simplified but equally effective means to grade GvHD. A total of 123 colon biopsies were assessed across four pathologists for intestinal GvHD using a Round-Robin test and results were correlated with clinical findings. Interobserver reproducibility was high for histological parameters that were evaluated as indicators of acute GvHD. Published grading systems were moderately reproducible (ICC 0.679-0.769) while simplified sum scores, in comparison, showed better interrater reliability (ICC 0.818-0.896). All grading systems and sum scores were associated with clinical signs of GvHD and in part with therapy response and survival. However, they were not able to stratify patients according to the clinical severity of GvHD. In a hot-spot analysis 1 crypt apoptotic body (CAB) in 10 crypts was a reasonable cut-off value for minimal diagnostic criteria of GvHD. In conclusion, histology can contribute to the diagnosis of GvHD and is reproducible. Published grading systems are able to reflect clinical findings as are simplified sum scores, which showed improved reproducibility and might be easier to handle as they are based on adding up histological parameters rather than transferring histological findings into a separate grading system. Sum scores will have to be further tested in a prospective setting.
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Colon , Enfermedad Injerto contra Huésped , Humanos , Reproducibilidad de los Resultados , Estudios Prospectivos , Colon/patología , Biopsia , Enfermedad Injerto contra Huésped/patología , Enfermedad AgudaRESUMEN
The solution properties of hydroxyethyl starch (HES) vary significantly owing to different measurement parameters adopted and sample structures. Here, a round-robin study was conducted to compare inter-laboratory measurements of solution properties, weight-average molecular weight (Mw), and molecular weight distribution of four HES candidates covering the low- and medium-molecular-weight range, and 50 commercially available HES 130/0.4 drug samples. Analysis was performed using size exclusion chromatography (SEC) combined with multi-angle laser light scattering (MALLS) and differential refractive index (dRI) detectors. The results indicate that HES molecules in the Mw range of 17,000-130,000, with varying degrees of substitution (between 0.4 and 0.8), yielded a refractive index increment (dn/dc) value of 0.145 ± 0.003 mL/g (solvent: acetic acid-sodium acetate buffer; wavelength: 658 nm) and that the second virial coefficient (A2) is correlated with Mw. The SEC-MALLS-dRI method for Mw determination of HES demonstrated good inter-laboratory reproducibility; however, the study findings suggest that column specifications should be added for HES quality standards. Comparing Mw results obtained using common and experimentally corrected dn/dc and A2 values revealed an influence of dn/dc and A2 on Mw, indicating that the Mw acceptance criteria of HES quality standards should be adjusted.
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Derivados de Hidroxietil Almidón , Refractometría , Cromatografía en Gel , Derivados de Hidroxietil Almidón/química , Rayos Láser , Luz , Peso Molecular , Reproducibilidad de los Resultados , Dispersión de RadiaciónRESUMEN
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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Droplet volume and temperature affect contact angle significantly. Phase change heat transfer processes of nanofluids - suspensions containing nanometre-sized particles - can only be modelled properly by understanding these effects. The approach proposed here considers the limiting contact angle of a droplet asymptotically approaching zero-volume as a thermophysical property to characterise nanofluids positioned on a certain substrate under a certain atmosphere. Graphene oxide, alumina, and gold nanoparticles are suspended in deionised water. Within the framework of a round robin test carried out by nine independent European institutes the contact angle of these suspensions on a stainless steel solid substrate is measured with high accuracy. No dependence of nanofluids contact angle of sessile droplets on the measurement device is found. However, the measurements reveal clear differences of the contact angle of nanofluids compared to the pure base fluid. Physically founded correlations of the contact angle in dependency of droplet temperature and volume are obtained from the data. Extrapolating these functions to zero droplet volume delivers the searched limiting contact angle depending only on the temperature. It is for the first time, that this specific parameter, is understood as a characteristic material property of nanofluid droplets placed on a certain substrate under a certain atmosphere. Together with the surface tension it provides the foundation of proper modelling phase change heat transfer processes of nanofluids.
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Delamination, which is the formation of flakes in drug products owing to specific and localized corrosion of glass vials, is a rare but serious problems, on which the FDA (U.S. Food and Drug Administration) put a warning to the pharma industry in 2011. The Technical Committee (TC) TC12 of the International Commission on Glass (ICG) was created in 2012 with the aim to study the problems related to pharma packaging. The first task of TC12 was to address the problem of predicting the propensity of glass vials to delamination, leaving the study of the mechanism(s) of flake formation as a possible future activity. This paper reports on the results obtained in a round robin test, which involved all the labs of the companies represented in the TC.Five types of vials with different expected delamination propensities were tested using a protocol that includes autoclaving at 121°C of vials filled with NaCl solution adjusted to pH 8 with NaOH solution, a coloration test, and ICP-OES determination of Si, B, and Al.Although there was no flake formation, the results showed that the combination of strong coloration at the bottom of the vials and high silicon concentration in the solution is correlated to an observable morphological modification/corrosion of the inner surface of vials in the bottom region. The test protocol is therefore useful for checking the quality of the vials with respect to the propensity to corrosion. Regarding delamination, no direct correlation with the testing results could be obtained yet. The method allows catching differences in the corrosion behavior, mainly between sets of vials with comparable surface:volume.LAY ABSTRACT: The U.S. Food and Drug Administration (FDA) warned the pharma industry about glass delamination inside primary packaging containers. Delamination is a type of glass corrosion that produces glass flakes, which could seriously affect patient health.Fortunately, delamination is a very rare event. On the other hand, it is very difficult to predict its occurrence. In 2012, the International Commission on Glass (ICG) created a Technical Committee (TC) on pharma packaging-with the initial goal to study an easy and reliable test for predicting the propensity of vials to delamination-involving the most important glass vial producers and pharma companies. This paper reports on the results obtained in a round robin test on different types of vials with different expected propensities to delamination. A specific testing protocol was adopted. In none of the vials, including those with an expected high propensity, glass flakes were observed, demonstrating that delamination is a rare event. However, the test is able to predict the occurrence of morphological modification/corrosion of the inner surface of vials in the bottom region. Therefore, the testing protocol is proposed as a method to evaluate differences in the corrosion behavior mainly between sets of vials with comparable surface:volume.
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Industria Farmacéutica/métodos , Embalaje de Medicamentos/normas , Almacenaje de Medicamentos , Vidrio/química , Corrosión , Concentración de Iones de Hidrógeno , Preparaciones Farmacéuticas/análisis , Estados Unidos , United States Food and Drug AdministrationRESUMEN
During the last decades, it has been observed a growing interest on odor impact because of the frequenter social acceptability problems about energy plants handling and processing stored organic materials (e.g., biogas plants, landfills, farms, distilleries, etc.). In this context, the UNI EN 13725:2004 indicates the "dynamic olfactometry method" as validated, recognized, and adequate measurement procedure for estimating the odor concentration. This protocol is carried out by a panel of specifically trained and selected human receptors, but alternative analytical methodologies are currently under discussion. This work aims to describe the initial steps of a wider research toward the definition of a new analytical protocol for monitoring odor concentration. The alternative methodology is here presented through the implementation of a case study: stored organic materials exploited on an energy plant in Central Italy. The paper describes the preliminary activities related to the survey of the case study (i), the definition of alternative methods and devices for conducting emissions sampling (ii), and the adopted experimental approach (iii). Finally, preliminary results are also presented (iv). The resulting protocol, once validated, could be employed by local authorities to measure both the odor impacts and the effectiveness of specifically designed mitigation strategies.
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Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Gases/análisis , Odorantes/análisis , Calibración , Monitoreo del Ambiente/instrumentación , ItaliaRESUMEN
INTRODUCTION: Cerebrospinal fluid α-synuclein level is increased in sporadic Creutzfeldt-Jakob disease cases. However, the clinical value of this biomarker remains to be established. In this study, we have addressed the clinical validation parameters and the interlaboratory reproducibility by using an electrochemiluminescent assay. METHODS: Cerebrospinal fluid α-synuclein was quantified in a total of 188 sporadic Creutzfeldt-Jakob disease and non-Creutzfeldt-Jakob-disease cases to determine sensitivity and specificity values and lot-to-lot variability. Two round robin tests with 70 additional cases were performed in six independent laboratories. RESULTS: A sensitivity of 93% and a specificity of 96% were achieved in discriminating sporadic Creutzfeldt-Jakob disease. No differences were detected between lots. The mean interlaboratory coefficient of variation was 23%, and the intralaboratory coefficient of variations ranged 2.70%-11.39%. Overall, 97% of samples were correctly diagnosed. DISCUSSION: The herein validated α-synuclein assay is robust, accurate, and reproducible in identifying Creutzfeldt-Jakob disease cases. Thus, it is ready for implementation in the clinical practice to support the diagnosis of Creutzfeldt-Jakob disease.
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1H quantitative NMR (1H qNMR) is known as a powerful tool for determination of analytes without the need for their identical standards, which is eligible to a primary rate method. 1H qNMR has been already stipulated to an assay for purity determination in Japanese Pharmacopoeia (JP), and then this technique has been also applied in several fields such as pharmaceutical and food sciences. However, there is little information about the accuracy of 1H qNMR so that the further applications into other fields such as industrial chemistry could be constricted. In this study, in order to assess the reliability of 1H qNMR, we designed the round-robin test of 1H qNMR under the basis of the measurement conditions described in JP. 1,4-Bis(trimethylsilyl)benzene-d4 [1,4-BTMSB-d4, 99.9±0.6% (w/w)] and 3,5-bis(trifluoromethyl)benzoic acid [3,5-BTMFBA, 99.96±0.06% (w/w)], which are certified reference materials (CRMs), were adopted to analyte and qNMR reference standard respectively for the accurate evaluation in this test. Six NMR instruments in 5 institutions optimized to 1H qNMR conditions provided the purity 1,4-BTMSB-d4 within acceptable error range. This result represented that 1H qNMR has the capability to determine precisely the value of analyte in practical analytical field and to be set as official analytical method for purity determination or assay of concentration of organic compounds.
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Espectroscopía de Resonancia Magnética/normas , Deuterio , Espectroscopía de Resonancia Magnética/instrumentación , Espectroscopía de Resonancia Magnética/métodos , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Even though allergies are an important health issue, wide manufacturer-dependent differences in the detected amounts of allergen-specific IgE (sIgE) have repeatedly been found. These discrepancies hinder diagnostics and research into clinically significant cutoff points for life-threatening symptoms. METHODS: To evaluate whether the reported differences have led to changes in diagnostic testing, we analyzed data from six years of round robin testing (RRT, also known as proficiency testing) at the Gesellschaft zur Förderung der Qualitätssicherung in medizinischen Laboratorien e.V. (Society for Promoting Quality Assurance in medical Laboratories) for the important allergen sources bee venom, wasp venom, and birch pollen. The results of the four main suppliers of in vitro diagnostic sIgE testing were compared in a pseudo-anonymized form using overlay images of box plot graphs for the semiquantitative data and allergen class results. Coefficients of variation (CV) were obtained to study the development of interlaboratory comparability. RESULTS: We found that the large differences between the manufacturer collectives remained constant between January 2010 and April 2015 without any real improvement. The CVs were good for two of the four analyzed suppliers, one was marginal and one above the quality level of 20%. CONCLUSION: The numerous publications that have found discrepancies in the sIgE results of the different suppliers did not change the status quo within the last six years. Unfortunately, this is unlikely to change until there is a characterized standard material with known values of sIgE.
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A European round robin test according to ISO 5725-2 was conceptually prepared, realised, and evaluated. The aim was to determine the inter-laboratory variability of the overall process for the ecotoxicological characterization of construction products in eluates and bioassays. To this end, two construction products BAM-G1 (granulate) and HSR-2 (roof sealing sheet), both made of EPDM polymers (rubber), were selected. The granular construction product was eluted in a one stage batch test, the planar product in the Dynamic Surface Leaching test (DSLT). A total of 17 laboratories from 5 countries participated in the round robin test: Germany (12), Austria (2), Belgium (1), Czech Republic (1) and France (1). A test battery of four standardised ecotoxicity tests with algae, daphnia, luminescent bacteria and zebrafish eggs was used. As toxicity measures, EC50 and LID values were calculated. All tests, except the fish egg test, were basically able to demonstrate toxic effects and the level of toxicity. The reproducibility of test results depended on the test specimens and the test organisms. Generally, the variability of the EC50 or LID values increased with the overall level of toxicity. For the very toxic BAM-G1 eluate a relative high variability of CV = 73%-110% was observed for EC50 in all biotests, while for the less toxic HSR-2 eluate the reproducibility of EC50 varied with sensitivity: it was very good (CV = 9.3%) for the daphnia test with the lowest sensitivity, followed by the algae test (CV = 36.4%). The luminescent bacteria test, being the most sensitive bioassay for HSR-2 Eluate, showed the highest variability (CV = 74.8%). When considering the complex overall process the reproducibility of bioassays with eluates from construction products was acceptable.
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Ecotoxicología/métodos , Pruebas de Toxicidad/métodos , Contaminantes Químicos del Agua/toxicidad , Animales , Bacterias/efectos de los fármacos , Bioensayo/métodos , Bioensayo/normas , Daphnia/efectos de los fármacos , Ecotoxicología/normas , Huevos , Elastómeros/toxicidad , Etilenos/toxicidad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Goma/toxicidad , Estramenopilos/efectos de los fármacos , Pruebas de Toxicidad/normas , Contaminantes Químicos del Agua/análisis , Pez CebraRESUMEN
Ki67 is a broadly used proliferation marker in surgical pathology with an obvious need for standardization to improve reproducibility of assessment. Here, we present results of the so far only existing round robin tests on Ki67, organized annually in Germany, Austria, and Switzerland from 2010 to 2015 with up to 160 participating laboratories (QuIP). In each quality assessment trial, eight probes from each breast cancer, neuroendocrine tumor, and malignant lymphoma were compiled on a tissue microarray (TMA). TMAs were stained in the participants' laboratories with antibodies and procedures also applied in their daily routine. Participating pathologists were expected to assign Ki67 values to one of four different categories for each tumor type. All local stainings and evaluations were reassessed by the organizing panel and compared to a preset standard. On average, 95% of participants reached the benchmark of over 80% concordance rates with the Ki67 category pre-established by the panel. Automatization and type of antibody did not affect the success rate. Concordance rates differed between tumor entities being highest in each tumor type with either very high or very low labeling indices. Lower rates were seen for intermediate Ki67 levels. Staining quality improved during the observation period as did inter-observer concordance with 85% of participants achieving excellent agreement (kappa > 0.8) in the first year and over 95% in 2015. In conclusion, regular external quality assurance trials have been established as a tool to improve the reproducibility and reliability of the prognostic and predictive proliferation marker Ki67.