Two-stage revision of infected shoulder arthroplasty using prosthesis of antibiotic-loaded acrylic cement: minimum three-year follow-up.

PURPOSE: This study aimed to evaluate the clinical outcomes and persistent infection rate of two-stage revision of infected shoulder arthroplasty. METHODS: We enrolled 12 patients who developed an infection after undergoing shoulder arthroplasty between January 2009 and January 2014. They underwent a two-stage revision with PROSTALAC implantation and shoulder re-implantation in the first- and second-stage surgery, respectively. The mean follow-up period was 40.88 months (range, 36-52 months). After the second-stage re-implantation, clinical scores, erythrocyte sedimentation rate, as well as C-reactive protein level were evaluated, and the presence of re-infection and complications were analyzed. RESULTS: Infection was improved in all the cases after PROSTALAC insertion. The mean range of motion of forward elevation, external rotation, and internal rotation at the final follow-up after the second-stage re-implantation were 81.67°, 40.42°, and 16.67° (vertebral level), respectively. The mean visual analog scale score improved from 7.08 points before surgery to 2.33 points after surgery. The Modified American Shoulder and Elbow Surgeons score improved from 32.25 before surgery to 64.17 after surgery (P < 0.05). The Constant shoulder score also improved from 30.92 before surgery to 66.08 after surgery (P < 0.05). Infection had not recurred until the final follow-up. However, dislocation and separation of components were found in two patients who needed a structural allograft because of segmental bone defects. CONCLUSION: Using PROSTALAC in two-stage revision arthroplasty is effective for infection control and produced good clinical outcomes after second-stage shoulder re-implantation. However, cases involving segmental bone defects require additional precautions in maintaining the appropriate tension and height to prevent complications.

Triblock copolymer matrix-based capillary electrophoretic microdevice for high-resolution multiplex pathogen detection.

Rapid and simple analysis for the multiple target pathogens is critical for patient management. CE-SSCP analysis on a microchip provides high speed, high sensitivity, and a portable genetic analysis platform in molecular diagnostic fields. The capability of separating ssDNA molecules in a capillary electrophoretic microchannel with high resolution is a critical issue to perform the precise interpretation in the electropherogram. In this study, we explored the potential of poly(ethyleneoxide)-poly(propyleneoxide)-poly(ethyleneoxide) (PEO-PPO-PEO) triblock copolymer as a sieving matrix for CE-SSCP analysis on a microdevice. To demonstrate the superior resolving power of PEO-PPO-PEO copolymers, 255-bp PCR amplicons obtained from 16S ribosomal RNA genes of four bacterial species, namely Proteus mirabilis, Haemophilus ducreyi, Pseudomonas aeruginosa, and Neisseria meningitidis, were analyzed in the PEO-PPO-PEO matrix in comparison with 5% linear polyacrylamide and commercial GeneScan gel. Due to enhanced dynamic coating and sieving ability, PEO-PPO-PEO copolymer displayed fourfold enhancement of resolving power in the CE-SSCP to separate same-sized DNA molecules. Fivefold input of genomic DNA of P. aeruginosa and/or N. meningitidis produced proportionally increased corresponding amplicon peaks, enabling correct quantitative analysis in the pathogen detection. Besides the high-resolution sieving capability, a facile loading and replenishment of gel in the microchannel due to thermally reversible gelation property makes PEO-PPO-PEO triblock copolymer an excellent matrix in the CE-SSCP analysis on the microdevice.

Improvement in the Microbial Resistance of Resin-Based Dental Sealant by Sulfobetaine Methacrylate Incorporation.

Prevention of dental caries is a key research area, and improvement of the pit and fissure sealants used for caries prevention has been of particular interest. This report describes results of incorporating a zwitterion, sulfobetaine methacrylate (SB), into photo-polymerized resin-based sealants to enhance resistance to cariogenic bacteria and protein adhesion. Varying amounts (1.5-5 wt%) of SB were incorporated into a resin-based sealant, and the flexural strength, wettability, depth of cure, protein adhesion, bacterial viability, and cell cytotoxicity of the resultant sealants were evaluated. The flexural strength decreased with the increasing SB content, but this decrease was statistically significant only for sealants containing ≥3 wt% SB. Incorporating a zwitterion led to a significant reduction in the water contact angle and protein adhesion. The colony-forming unit count showed a significant reduction in the bacterial viability of S. mutans, which was confirmed with microscopic imaging. Moreover, cell cytotoxicity analysis of SB-modified sealants using an L929 fibroblast showed a cytotoxicity comparable to that of an unmodified control, suggesting no adverse effects on the cellular metabolism upon SB introduction. Hence, we conclude that the addition of 1.5-3 wt% SB can significantly enhance the inherent ability of sealants to resist S. mutans adhesion and prevent dental caries.