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Aseptic loosening and osteolysis of joint replacements are driven by macrophage-mediated inflammatory reactions to implant-derived wear debris, but many aspects of these events remain poorly characterized. To better understand the relationships among inflammatory and chemotactic mediators, macrophage phenotype and polarizing cytokines, osteoclast activity, and Toll-like receptors (TLRs) in the pathogenesis of aseptic loosening, we determined how the relative expressions of these factors in the peri-implant tissues correlate to each other and to the life span of the implants using Pearson correlation. The expression of pro-inflammatory mediators and chemokines showed positive correlations among themselves, and with TLR4. Furthermore, M1-polarizing IFN-γ showed positive correlations with a number of pro-inflammatory and chemotactic mediators, whereas M2-polarizing IL-4 showed no such association. IL-8 expression significantly correlated with early time to revision. Similar trends were observed for TNF-α, IFN-γ, and CCL3, while the opposite was detected for IL-4. However, none of the inflammatory mediators correlated with the markers of osteoclast activity or the RANKL/OPG ratio. The results highlight the importance of the inflammatory mediators, IFN-γ and TLR4, in the pathogenesis of aseptic loosening; increased pro-inflammatory status was associated with early time to revision, whereas IL-4 correlated with longer implant survival. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 454-463, 2017., (© 2016 Wiley Periodicals, Inc.)

Staphylococcus aureus device-related infection is a common complication in implantology. Bacterial adhesion on implant surfaces is the initial step in the infective process. The aim was to develop a method suitable for quantitative bacterial adherence studies and to test a new diamond-like carbon (DLC) coating against commonly used metallic biomaterials with regards to Staphylococcus aureus adhesion. Patterned silicon chips with spots of tantalum, titanium, chromium, and DLC were produced using ultraviolet lithography and physical vapor deposition. These patterned chips were used as such or glued to array plates, pretreated with serum and exposed to S. aureus (S-15981) for 90 min, followed by acridine orange staining and fluorescence microscopy. An adhesion index showed that the ranking order of the biomaterials was titanium, tantalum, chromium, and DLC, with the DLC being clearly most resistant against colonization with S. aureus. Micropatterned surfaces are useful for quantitative comparison of bacterial adherence on different biomaterials. In the presence of serum, DLC is superior in its ability to resist adhesion and colonization by S. aureus compared with the commonly used biomaterial metals tantalum, titanium, and chromium., ((c) 2009 Wiley Periodicals, Inc.)

Staphylococci cause the majority of the nosocomial implant-related infections initiated by adhesion of planktonic bacteria to the implant surface. It was hypothesized that plasma accelerating filtered pulsed arc discharge method enables combination of the advantageous properties of diamond with the antisoiling properties of polymers. Diamond-like carbon polytetrafluoroethylene hybrid (DLC-PTFE-h) coating was produced. The adhesion of S. aureus ATCC 25923 (10(8) colony-forming units/mL) to surfaces diminished from 2.32%, 2.35%, and 2.57% of high quality DLC, titanium, and oxidized silicon, respectively, to 1.93% of DLC-PTFE-h. For S. epidermidis ATCC 35984 the corresponding figures were 3.90%, 3.32%, 3.47%, and 2.57%. Differences in bacterial adhesion between recombinant DLC-PTFE-h and other materials were statistically significant (p < 0.05). In contrast, human Caco-2 cells adhered as well to DLC-PTFE-h as to DLC, titanium, or silicon, which were all in the MTT test found to be cytocompatible. DLC-PTFE-h coating can be used to modify the surface properties of any surgical implants and is an unfavorable substrate for staphylococcal cells, but compatible with human Caco-2 cells. DLC-PTFE-h coating may help in the combat against Staphylococcus-related implant infections which usually require both antibiotics and surgical removal of the implant for cure.