CfDNA samples from colon (mCRC) and non-small cell lung cancers (NSCLC) (CIRCAN cohort) were compared using three platforms: droplet digital PCR (ddPCR, Biorad); BEAMing/OncoBEAM™-RAS-CRC (Sysmex Inostics); next-generation sequencing (NGS, Illumina), utilizing the 56G oncology panel (Swift Biosciences). Tissue biopsy and time matched cfDNA samples were collected at diagnosis in the mCRC cohort and during 1st progression in the NSCLC cohort. Excellent matches between cfDNA/FFPE mutation profiles were observed.
View Article and Find Full Text PDFNon invasive somatic detection assays are suitable for repetitive tumor characterization or for detecting the appearance of somatic resistance during lung cancer. Molecular diagnosis based on circulating free DNA (cfDNA) offers the opportunity to track the genomic evolution of the tumor, and was chosen to assess the molecular profile of several alterations, including deletions in exon 19 (delEX19), the L858R substitution on exon 21 and the EGFR resistance mutation T790M on exon 20. Our study aimed at determining optimal pre-analytical conditions and mutation detection assays for analyzing cfDNA using the picoliter-droplet digital polymerase chain reaction (ddPCR) assay.
View Article and Find Full Text PDFA PMA (propidium monoazide) pretreatment protocol, in which PMA is applied directly to membrane filters, was developed for the PCR-based quantification (PMA-qPCR) of viable Legionella pneumophila. Using this method, the amplification of DNA from membrane-damaged L. pneumophila was strongly inhibited for samples containing a small number of dead bacteria.
View Article and Find Full Text PDFStaphylococcus aureus necrotizing pneumonia is a severe disease caused by S. aureus strains carrying the Panton Valentine leukocidin (PVL) genes (lukS-PV & lukF-PV) encoded on various bacteriophages (such as phiSLT). Clinical PVL+ strains isolated from necrotizing pneumonia display an increased attachment to matrix molecules (type I and IV collagens and laminin), a phenotype that could play a role in bacterial adhesion to damaged airway epithelium during the early stages of necrotizing pneumonia (J Infect Dis 2004; 190: 1506-15).
View Article and Find Full Text PDFLegionella pneumophila is the causative agent of Legionnaires' disease. This bacterium is ubiquitous in aqueous environments and uses amoebae as an intracellular replicative niche. Real-time PCR has been developed for rapid detection of Legionella DNA in water samples.
View Article and Find Full Text PDF