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Biology subjects

Mauri, L.

Publications and source records attributed to Mauri, L..

2 recordsLinked to original sources

CRISPRcleanR WebApp: an interactive web application for processing genome-wide pooled CRISPR-Cas9 viability screen

A limitation of pooled CRISPR-Cas9 viability screens is the high false-positive rate in detecting essential genes arising from copy number-amplified (CNA) regions of the genome. To solve this issue, we developed CRISPRcleanR: a computational method implemented as R/python package and in a dockerized version. CRISPRcleanR detects and corrects biased responses to CRISPR-Cas9 targeting in an unsupervised fashion, accurately reducing false-positive signals, while maintaining sensitivity in identifying relevant genetic dependencies. Here, we present CRISPRcleanRWebApp, a web-based application enabling access to CRISPRcleanR through an intuitive graphical web-interface. CRISPRcleanRWebApp removes the complexity of low-level R/python-language user interactions; it provides a user-friendly access to a complete analytical pipeline, not requiring any data pre-processing, and generating gene-level summaries of essentiality with associated statistical scores; it offers a range of interactively explorable plots, while supporting a wider range of CRISPR guide RNAs libraries with respect to the original package. CRISPRcleanRWebApp is freely available at: https://crisprcleanr-webapp.fht.org/. HighlightsO_LICRISPR-Cas9 screens are widely used for the identification of cancer dependencies C_LIO_LIIn such screens, false-positives arise from targeting copy number amplified genes C_LIO_LICRISPRcleanR corrects this bias in an unsupervised fashion C_LIO_LICRISPRcleanRWebApp is a web user-friendly front-end for CRISPRcleanR C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/483924v2_ufig1.gif" ALT="Figure 1"> View larger version (56K): org.highwire.dtl.DTLVardef@739480org.highwire.dtl.DTLVardef@1a6c0aorg.highwire.dtl.DTLVardef@ab2b8eorg.highwire.dtl.DTLVardef@1b8a623_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

Using ATR-FTIR spectroscopy to characterise crude heparin samples by composition and structural features.

Production of the major anticoagulant drug, heparin, is a complex process that begins with the collection of crude material from a dispersed network of suppliers with poor traceability, an issue that was made apparent in 2007-2008, when batches of heparin were contaminated deliberately in the supply chain, resulting in over 100 deaths in the US alone. Several analytical techniques are used currently for the characterisation of pharmaceutical grade heparin, but few have been applied to its crude counterpart. One exception is NMR spectroscopy which was used to study crude heparin (2017), however, owing to the high set-up and running costs, as well as the need for skilled technical operators, the use of NMR at crude heparin production plants is unviable. An alternative, practical, spectroscopic method is attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) that is user-friendly, economical and, importantly, requires little specialised training or sample preparation. Using a top-down chemometric approach employing principal component analysis, ATR-FTIR spectroscopy was able to distinguish crude heparins based on their similarity to pharmaceutical heparin, as well as on their compositional and structural features, which included levels of sulphation, the extent of related conformational changes, as well as the quantities of chondroitin and dermatan sulphate present. This approach lends itself to automation and will enable users and regulators to undertake quality control of crude heparin during manufacture. The method requires only economical, portable equipment and little specialised training, bringing the high-quality analysis of crude heparin within reach of both manufacturers and regulators for the first time.

biochemistry↗