High-resolution melting analysis for rapid characterization of qnr alleles in clinical isolates and detection of two novel alleles, qnrB25 and qnrB42.

Objectives: qnr genes are plasmid-mediated quinolone resistance genes. Five qnr families have been described with several alleles (7 alleles of qnrA, 53 alleles of qnrB, 1 allele of qnrC, 1 allele of qnrD and 6 alleles of qnrS). Their detection requires a PCR specific for each qnr family and further sequencing for allele characterization.

Preliminary investigation of a mice model of Klebsiella pneumoniae subsp. ozaenae induced pneumonia.

In the present study, we comparatively assessed the pathophysiological mechanisms developed during lung infection of BALB/C female mice infected by an original wild type Klebsiella pneumoniae subsp. ozaenae strain (CH137) or by a referent subspecies K. pneumoniae.

Rapid detection of qnr and qepA plasmid-mediated quinolone resistance genes using real-time PCR.

Plasmid-mediated quinolone resistance genes in clinical strains cannot be detected by phenotypic traits but require gene detection. We developed a multiplex real-time polymerase chain reaction (PCR) assay using high-resolution melting master mix with ResoLight dye to detect qnr genes and a simplex real-time PCR assay using SYBR Green I to detect qepA genes. Using qnr-positive and qepA1-positive control strains, the ResoLight method was able to rapidly identify qnrA, qnrB, qnrS, qnrC, and qnrD genes; the SYBR Green I method identified qepA genes.

Rapid detection of aac(6')-Ib-cr quinolone resistance gene by pyrosequencing.

Pyrosequencing was used to rapidly detect aac(6')-Ib and aac(6')-Ib-cr genes. This plasmid-mediated quinolone resistance determinant is increasing in extended-spectrum beta-lactamase-producing Enterobacteriaceae. This method is faster and more cost-effective than the methods previously described.

Human Bocavirus quantitative DNA detection in French children hospitalized for acute bronchiolitis.

Background: Human Bocavirus (HBoV) is a newly discovered parvovirus whose role as a causative agent of respiratory disease remains unclear.

Study Design: We investigated the presence of HBoV by quantitative PCR in the nasopharyngeal samples of 192 French children consecutively hospitalized for acute bronchiolitis. Other common respiratory viruses were detected using immunofluorescence assays, cell culture detection, or RT-PCR assays.