METHOD: We created an iontophoresis cell; 3% CF was inserted within medullary segment of goat bone and sealed from external saline solution. The cell operated at the following voltages 30, 60 and 90 V and at the following durations 5, 10, 15, 20, 25 and 30 min. Information regarding optimal conditions for its application was then obtained. After which, correlation between voltages and time with CF concentration in the bone was analysed. A bioavailability test was also conducted to observe the optimal rate of CF elution from the graft.
RESULT: The optimal condition for the impregnation process is 3% CF at 90 V for 10 min. Bone graft impregnated with CF at optimal conditions can elute above minimum inhibitory concentration of the CF against MRSA for 21 days.
CONCLUSION: CF iontophoresis was found feasible for allograft impregnation. The technique is simple, inexpensive and reproducible clinically. Iontophoresis offers a novel solution to reduce the rate of perioperative infection in reconstructive surgery involving use of bone graft.
IMPORTANCE: With increasing levels of CA-MRSA reported from most parts of the Western world, there is a great interest in understanding the origin and factors associated with the emergence of these epidemic lineages. To trace the origin, evolution, and dissemination pattern of the European CA-MRSA clone (CC80), we sequenced a global collection of strains of the S. aureus CC80 lineage. Our study determined that a single descendant of a PVL-positive methicillin-sensitive ancestor circulating in sub-Saharan Africa rose to become the dominant CA-MRSA clone in Europe, the Middle East, and North Africa. In the transition from a methicillin-susceptible lineage to a successful CA-MRSA clone, it simultaneously became resistant to fusidic acid, a widely used antibiotic for skin and soft tissue infections, thus demonstrating the importance of antibiotic selection in the success of this clone. This finding furthermore highlights the significance of horizontal gene acquisitions and underscores the combined importance of these factors for the success of CA-MRSA.
METHODS: The antimicrobial activity was tested against the planktonic S. aureus cells using the microdilution broth assay, while the antibiofilm activity were evaluated using the crystal violet and resazurin assays. The cytotoxicity of the SBDs was assessed on MRC5 (normal lung tissue), using the MTT assay.
RESULTS: The individual SBDs showed significant reduction of biomass and metabolic activity in both S. aureus strains. Combinations of the SBDs with OXA and VAN were mainly additive against the planktonic cells and cells in the biofilm. Both the compounds showed moderate toxicity against the MRC5 cell line. The selectivity index suggested that the compounds were more cytotoxic to S. aureus than the normal cells.
CONCLUSION: Both the SBD compounds demonstrated promising antimicrobial and antibiofilm activities and have the potential to be further developed as an antimicrobial agent against infections caused by MRSA.