Although early antibiotic treatment of patients with septic arthritis eradicates bacteria, joint destruction commonly results from the unregulated host inflammatory responses to infection. The spin trap compound phenyl-N-tert-butyl nitrone (PBN) has been shown to have both anti-inflammatory and antioxidant effects. The aim of this study was to assess the effect of combined systemic administration of PBN and cloxacillin on the development of Staphylococcus aureus arthritis. Three days after Naval Medical Research Institute (NMRI) mice were infected intravenously with S. aureus LS-1, daily treatment was started with cloxacillin alone, PBN alone, or cloxacillin and PBN. Arthritis, weight loss and general condition were evaluated for each mouse, and joints were analyzed histopathologically. Systemic administration of PBN in conjunction with cloxacillin ameliorated the course of experimental S. aureus arthritis, as evidenced by an increased cure rate. Thus, combinatorial antioxidant plus antibiotic anti-inflammatory therapies represent a potentially efficacious approach to the management of septic arthritis.

Quarterly Sampling Reports for antimicrobial resistance, specifically in cecal and product. Product reports consist of data for Salmonella, Campylobacter, and Shiga toxin-producing Escherichia coli (STEC). Reports are updated annually. See the FSIS website for additional information.

Between 2016 and 2021, 2398 samples of raw ground beef, veal and lamb were collected at retail stores across Canada. Samples were tested for STEC O157 and non-O157 STEC. STEC O157 and non-O157 STEC were found in 0.1% (3/2398) and 6.0% (145/2398) of the ground meat samples respectively. The prevalence of STEC O157 in Canadian retail raw ground meat is low, similar to ground beef produced from processing facilities. All STEC virulence gene profiles were assessed using criteria of the FAO/WHO risk categories and the majority of the STEC strains were classified as belonging to risk level 5 which is the lowest risk level. This study indicates that the current food safety control measures implemented for ground meats in Canada are effective at maintaining an acceptable level of possible contamination with STEC strains associated with severe clinical outcomes.

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,A requirement of any foodborne pathogen testing method is that it only detects live bacteria. Ethidium monoazide (EMA) and propidium monoazide (PMA) are dyes that penetrate the membranes of dead cells and form cross-linkages in the DNA, which prevents its amplification in PCR. This study investigated whether treatment with EMA or PMA would inhibit sequencing of DNA from dead Escherichia coli. Range finding experiments with qPCR were conducted to determine the optimal concentrations of EMA and PMA needed to inhibit amplification of DNA from dead cells while not influencing live cells. An EMA concentration that differentiated between live and dead cells could not be established. However, a PMA concentration of 25 µM effectively prevented qPCR amplification of DNA from dead E. coli while not impacting the amplification of live E. coli DNA. Sequencing experiments were conducted with PMA-treated live, untreated live, PMA-treated dead, and untreated dead E. coli. There were no significant differences in the detection of virulence genes of interest between the PMA-treated live, untreated live, and untreated dead E. coli. However, no DNA sequencing data was obtained from the PMA-treated dead E. coli. These results suggest that PMA could be incorporated into sample preparation methods prior to sequencing to selectively detect live cells of foodborne pathogens.,