Adhesion of meticillin-resistant Staphylococcus aureus to DACC-coated dressings.

OBJECTIVE: The aim of this in vitro study was to demonstrate the binding capacity of multiple meticillin-resistant Staphylococcus aureus (MRSA) strains and compare the binding capacity to meticillin-sensitive Staphylococcus aureus. METHOD: The binding of Staphylococcus aureus to a surface was assessed by bioluminescent monitoring of the bacterial ATP levels. This assay can be used as an in vitro diagnostic model for bacteria binding in a critically colonised wound. RESULTS: Eleven strains of Staphylococcus aureus were examined including MRSA, all of which efficiently and equally adhered to the dialkyl carbamoyl chloride (DACC)-coated dressing (Sorbact; Abigo Medical AB). The binding capacity was all in the same range 0.7-2.9 × 106 CFU/cm². regardless of the antibiotic resistance properties of the specific strain. CONCLUSION: The decrease of wound bioburden of Staphylococcus aureus including MRSA is the result of the high binding capacity shown in this study and by earlier data. The findings in this study strengthen the held view that development of antibiotic resistance has minimal impact on the surface structures of the microorganisms in wounds.

Heart rate variability and sustained attention in ADHD children.

The major goal of the current study was to investigate the association between continuous performance tests (CPTs) and the heart rate variability (HRV) of attention deficit hyperactivity disorder (ADHD) children. The HRV, specifically the 0.10-Hz component, may be considered to be a psychophysiological index of effort allocation (motivation): The less effort the subject allocates, the greater the 0.10-Hz component. Results indicated that, compared to controls, ADHD subjects had a greater 0.10-Hz component, which was associated with poor test performance over time. Thus, using a psychophysiological measure, we were able to confirm the clinical concept of ADHD from a motivational perspective.

Attachment of Escherichia coli O157:H7 in ground beef to meat grinders and survival after sanitation with chlorine and peroxyacetic acid.

The potential for transfer of Escherichia coli O157:H7 from contaminated ground beef to grinding equipment and the inactivation of attached cells during cleaning and sanitizing was examined. Chub-packed ground beef with lean:fat ratios of 75:25, 80:20 or 90:10 was inoculated with 6 log CFU/g or 2 log CFU/g E. coli O157:H7 strain FRIK 910. Samples were consecutively ground in a Hobart meat grinder with stainless steel (SS) chips (1 cm2) glued to the auger housing. Chips were harvested after grinding, detergent washing with or without manual scrubbing and rinsing, sanitizing in a chlorine or peroxyacetic acid sanitizer, and overnight storage. Survival of E. coli O157:H7 was evaluated both by plate count and enrichment in trypticase soy broth. Approximately 3 to 4 log CFU/cm2 were attached to the SS after grinding with all three fat contents. After washing and sanitizing in a chlorine or peroxyacetic acid sanitizer, viable bacteria were infrequently recovered by plate count. Enrichment of chips resulted in a higher survival rate with both sanitizing treatments, indicating that cell numbers below the limit of detection (5 CFU/cm2) or potentially injured organisms remained on the surface. Manual scrubbing during the washing step reduced the recovery rate. The scrubbing step also increased the number of passing scores assigned using an ATP bioluminescence assay of total residual soil on the chips sanitized in chlorine. The overall results indicate that plate counts alone may not be a reliable indicator of sanitation efficacy and may be validated by enrichment assay.