Fergal J. O'Brien

Treating bone infections and ensuring bone repair is one of the greatest global challenges of modern orthopedics, made complex by antimicrobial resistance (AMR) risks due to long‐term antibiotic treatment and debilitating large bone defects following infected tissue removal. An ideal multi‐faceted solution would will eradicate bacterial infection without long‐term antibiotic use, simultaneously stimulating osteogenesis and angiogenesis. Here, a multifunctional collagen‐based scaffold that addresses these needs by leveraging the potential of antibiotic‐free antimicrobial nanoparticles (copper‐doped bioactive glass, CuBG) to combat infection without contributing to AMR in conjunction with microRNA‐based gene therapy (utilizing an inhibitor of microRNA‐138) to stimulate both osteogenesis and angiogenesis, is developed. CuBG scaffolds reduce the attachment of gram‐positive bacteria by over 80%, showcasing antimicrobial functionality. The antagomiR‐138 nanoparticles induce osteogenesis of human mesenchymal stem cells in vitro and heal a large load‐bearing defect in a rat femur when delivered on the scaffold. Combining both promising technologies results in a multifunctional antagomiR‐138‐activated CuBG scaffold inducing hMSC‐mediated osteogenesis and stimulating vasculogenesis in an in vivo chick chorioallantoic membrane model. Overall, this multifunctional scaffold catalyzes killing mechanisms in bacteria while inducing bone repair through osteogenic and angiogenic coupling, making this platform a promising multi‐functional strategy for treating and repairing complex bone infections.

Introduction: Recent decades have seen a move to minimally invasive techniques to manage urolithiasis. Trainees are expected to develop competency in common endourology procedures. Knowledge of ureter mechanics and the theory behind new technologies is important to ensure safe and efficient techniques. We aim to evaluate the exposure to endourology, self-reported competency in common techniques and knowledge of basic ureter biomechanics and technology in training urologists. Methods: An online survey was circulated to all training urologists in the Republic of Ireland. Questions focused on self-reported competency, clinical knowledge, ureter mechanical properties and laser technology. Results: Thirty responses were received with a range of 1-8 years of urology experience (mean=4 years). The respondents reported high levels of exposure to endourology with the majority reporting competency in flexible ureterorenoscopy (FURS) (n=18, 60%) and semi-rigid ureteroscopy (URS) (n=21, 70%). The respondents demonstrated good clinical knowledge but variable knowledge of laser settings, laser thermodynamics and ureter mechanics. Half of the respondents (n=15, 50%) correctly described fragmentation laser settings, with 10 trainees (n=33%) accurately identifying both factors that increase ureteral access sheath (UAS) insertion force. Most of the respondents (n=20, 67%) described the proximal ureter as the site with the greatest compliance, while the site of the greatest force during ureteroscope insertion was correctly identified by 17% (n=5). Conclusion: To our knowledge, this represents the first study evaluating urologist understanding of laser technology and the mechanical properties of the human ureter. Despite trainees reporting high levels of experience in endourology, there is a variable understanding of the principles of laser technology and ureter mechanics. Further research and education are needed with a focus on laser safety, suitable laser settings and the safe limit of insertion forces.