Extraction et analyse de traces d'oligo- et polysaccharides - (application au contrôle qualité des miels)

La lutte contre la fraude dans le domaine agroalimentaire est un souci permanent pour garantir aux consommateurs des produits de qualité. La production limitée et le prix élevé du miel amènent parfois des pratiques de falsification difficiles à déceler tant au niveau de son origine (appellation) que de sa composition (par l ajout délibéré de sirop de sucre bon marché). L analyse des sucres, constituants majoritaires du miel, est l une des méthodes les plus utilisées pour mettre en évidence ces techniques de fraude. Afin de rendre plus efficace les méthodes actuellement utilisées pour l authentification et le contrôle de la qualité des miels, la recherche de nouveaux marqueurs a été entreprise par extraction sur phase solide et chromatographie des oligo- et polysaccharides. Malgré la variabilité des compositions rencontrées dans ces produits naturels, des profils chromatographiques ont permis de caractériser certaines variétés de miel et de détecter des adultérations dès l ajout de 1 % de sirop de sucre. Cette approche amène de nouvelles solutions et perspectives pour certifier l appellation d un miel et contrer les techniques de falsification qui existent sur le marchéThe fight against the fraud in the agro-alimentary field is a permanent problem to warrant quality products to the consumers. The limited production and the high price of honey provoke falsification practices which are difficult to detect on its origin (appellation) and its composition (by the deliberated addition of cheap sugar syrup). The analysis of sugars, major : In order to improve the current methods for the authentification and the quality control of honeys, the search of new probes was undertaken by solid phase extraction and chromatography of oligo- and polysaccharides. In spite of the great variability of the compositions in these natural products, chromatographic fingerprints allowed to discriminate some varieties of honey and to detect adulterations from an addition of 1 % of sugar syrup. This approach leads new solutions and perspectives to certify a variety of honey and to fight against the falsification techniques which exist on the marketLYON1-BU.Sciences (692662101) / SudocSudocFranceF

Simultaneous analysis of eight nucleoside triphosphates in cell lines by liquid chromatography coupled with tandem mass spectrometry.

International audienc

Overview of accessibility and quality of antiepileptic drugs in Madagascar

International audiencePURPOSE:To determine the accessibility of treatment and the quality of antiepileptic drugs (AEDs) in the Haute Matsiatra district of Madagascar.METHODS:Cross-sectional descriptive study and interviews. Samples of 10 units of each available AED were collected, and the active ingredient was quantified by reversed-phase high-performance liquid chromatography (RP-HPLC) with photodiode-array UV detection. The quality of an AED was considered satisfactory if the quantity of active ingredient in each tablet was in the range ±15% of the average value according to the European Pharmacopeia (6th edition, 2008).RESULTS:The area was well served with health infrastructure but rescue facilities were poorly distributed. Available AEDs were all first-generation, and 73% were generic formulations. People with epilepsy (PWE) surveyed consulted traditional healers and most were treated with plants. PWE did not consider themselves sick but believed they were "possessed"; they consulted a doctor only immediately after a seizure, following the advice of traditional healers. The most prescribed AED was phenobarbital, costing between 0.03 and 0.12 US Dollar (US$) per 100mg. The purchase of full treatment was difficult for 77% of PWE and as a result, 39% took nothing. The quality of AEDs were considered unsatisfactory in 2.8% of cases.CONCLUSION:The AEDs collected in Haute Matsiatra were globally of good quality. The main limiting elements were a lack of knowledge among PWE that epilepsy is a disease, and the cost of traditional treatments

Cross-oncopanel study reveals high sensitivity and accuracy with overall analytical performance depending on genomic regions.

Targeted sequencing using oncopanels requires comprehensive assessments of accuracy and detection sensitivity to ensure analytical validity. By employing reference materials characterized by the U.S. Food and Drug Administration-led SEquence Quality Control project phase2 (SEQC2) effort, we perform a cross-platform multi-lab evaluation of eight Pan-Cancer panels to assess best practices for oncopanel sequencing. All panels demonstrate high sensitivity across targeted high-confidence coding regions and variant types for the variants previously verified to have variant allele frequency (VAF) in the 5-20% range. Sensitivity is reduced by utilizing VAF thresholds due to inherent variability in VAF measurements. Enforcing a VAF threshold for reporting has a positive impact on reducing false positive calls. Importantly, the false positive rate is found to be significantly higher outside the high-confidence coding regions, resulting in lower reproducibility. Thus, region restriction and VAF thresholds lead to low relative technical variability in estimating promising biomarkers and tumor mutational burden. This comprehensive study provides actionable guidelines for oncopanel sequencing and clear evidence that supports a simplified approach to assess the analytical performance of oncopanels. It will facilitate the rapid implementation, validation, and quality control of oncopanels in clinical use.All SEQC2 participants freely donated their time, reagents, and computing resources for the completion and analysis of this project. Part of this work was carried out with the support of the Intramural Research Program of the National Institutes of Health (to Mehdi Pirooznia), National Institute of Environmental Health Sciences (to Pierre Bushel), and National Library of Medicine (to Danielle Thierry-Mieg, Jean Thierry-Mieg, and Chunlin Xiao). Leming Shi and Yuanting Zheng were supported by the National Key R&D Project of China (2018YFE0201600), the National Natural Science Foundation of China (31720103909), and Shanghai Municipal Science and Technology Major Project (2017SHZDZX01). Donald J. Johann, Jr. acknowledges the support by FDA BAA grant HHSF223201510172C. Timothy Mercer and Ira Deveson were supported by the National Health and Medical Research Council (NHMRC) of Australia grants APP1108254, APP1114016, and APP1173594 and Cancer Institute NSW Early Career Fellowship 2018/ECF013. This research has also been, in part, financially supported by the MEYS of the CR under the project CEITEC 2020 (LQ1601), by MH CR, grant No. (NV19-03-00091). Part of this work was carried out with the support of research infrastructure EATRIS-CZ, ID number LM2015064, funded by MEYS CR. Boris Tichy and Nikola Tom were supported by research infrastructure EATRIS-CZ, ID number LM2018133 funded by MEYS CR and MEYS CR project CEITEC 2020 (LQ1601).S

A comprehensive assessment of RNA-seq accuracy, reproducibility and information content by the Sequencing Quality Control Consortium

We present primary results from the Sequencing Quality Control (SEQC) project, coordinated by the US Food and Drug Administration. Examining Illumina HiSeq, Life Technologies SOLiD and Roche 454 platforms at multiple laboratory sites using reference RNA samples with built-in controls, we assess RNA sequencing (RNA-seq) performance for junction discovery and differential expression profiling and compare it to microarray and quantitative PCR (qPCR) data using complementary metrics. At all sequencing depths, we discover unannotated exon-exon junctions, with >80% validated by qPCR. We find that measurements of relative expression are accurate and reproducible across sites and platforms if specific filters are used. In contrast, RNA-seq and microarrays do not provide accurate absolute measurements, and gene-specific biases are observed for all examined platforms, including qPCR. Measurement performance depends on the platform and data analysis pipeline, and variation is large for transcript-level profiling. The complete SEQC data sets, comprising >100 billion reads (10Tb), provide unique resources for evaluating RNA-seq analyses for clinical and regulatory settings