Metal-on-metal (MOM) bearings involving cobalt-chromium (Co-Cr) alloys in total hip arthroplasties are becoming more and more popular due to their low wear. Consequences of corrosion products of Co-Cr alloys are for the most part unclear, and the influence of cobalt and chromium ions on biofilm formation has never been studied. Therefore, the aim of this study was to evaluate how Co-Cr ions affect bacterial growth, biofilm formation, and architecture.
View Article and Find Full Text PDFWe introduce a procedure for determining shear forces at the balance between attachment and detachment of bacteria under flow. This procedure can be applied to derive adhesion forces in weak-adherence systems, such as polymer brush coatings, which are currently at the center of attention for their control of bacterial adhesion and biofilm formation.
View Article and Find Full Text PDFAppl Environ Microbiol
November 2007
Otolaryngol Head Neck Surg
September 2007
Objective: We sought to identify bacterial strains responsible for biofilm formation on silicone rubber voice prostheses.
Study Design: We conducted an analysis of the bacterial population in biofilms on used silicone rubber voice prostheses by using new microbiological methods.
Methods: Two microbiological methods were used: polymerase chain reaction-denaturing gradient gel electrophoresis and fluorescence in situ hybridization.
The salivary pellicle is a negatively charged protein film, to which oral bacteria readily adhere. Chitosans are cationic biomolecules with known antimicrobial properties that can be modified in different ways to enhance its antimicrobial activity. Here, we determined the changes in surface chemical composition using X-ray photoelectron spectroscopy (XPS), in hydrophobicity by analyzing water contact angles, in charge through measuring streaming potentials, and evaluated morphology using atomic force microscopy (AFM), of salivary pellicles upon adsorption of different chitosans.
View Article and Find Full Text PDFThe antigen I/II family of surface proteins is expressed by oral streptococci, including Streptococcus mutans, and mediates specific binding to, among others, salivary films. The aim of this study was to investigate the interaction forces between salivary proteins and S. mutans with (LT11) and without (IB03987) antigen I/II through atomic force microscopy (AFM) and to relate these interaction forces with the adhesion of the strains to saliva-coated glass in a parallel plate flow chamber.
View Article and Find Full Text PDFBiomaterial-related infection of joint replacements is the second most common cause of implant failure, with serious consequences. Chronically infected replacements cannot be treated without removal of the implant, as the biofilm mode of growth protects the bacteria against antibiotics. This review discusses biofilm formation on joint replacements and the important clinical phenomenon of small-colony variants (SCVs).
View Article and Find Full Text PDFPeri-operative contamination is the major cause of biomaterial-associated infections, highly complicating surgical patient outcomes. While this risk in traditional implanted biomaterials is well-recognised, newer cell-seeded, biologically conducive tissue-engineered (TE) constructs now targeted for human use have not been assessed for this possibility. We investigated infection incidence of implanted, degradable polyester TE scaffold biomaterials in rabbit knee osteochondral defects.
View Article and Find Full Text PDFThis study examined bacterial adhesion to a new multi-component cross-linked poly(ethylene glycol)-based polymer coating that can be applied by spin-coating or spraying onto diverse biomaterials. Adhesion of five clinically isolated bacterial strains involved in biomaterial-centered infections were studied in a parallel-plate flow chamber at different shear rates and after exposure of the coating to different physiological fluids. The new chemistry inhibits non-specific biomolecular and cell binding interactions.
View Article and Find Full Text PDFThe attachment of waterborne pathogens onto surfaces can be increased by coating the surfaces with positive charge-enhancing polymers. In this paper, the increased efficacy of polydiallyldimethylammonium chloride (p-DADMAC) coatings on glass was evaluated in a parallel plate flow chamber with the use of waterborne pathogens (Raoultella terrigena, Escherichia coli, and Brevundimonas diminuta). p-DADMAC coatings strongly compensated the highly negative charges on the glass surface and even yielded a positively charged surface when applied from a 500 ppm solution.
View Article and Find Full Text PDFA method is presented to prevent microbial adhesion to solid surfaces exploiting the unique properties of polymer brushes. Polyacrylamide (PAAm) brushes were grown from silicon wafers by atom transfer radical polymerization (ATRP) using a three-step reaction procedure consisting of immobilization of a coupling agent gamma-aminopropyltriethoxysilane, anchoring of an ATRP initiator 4-(chloromethyl)benzoyl chloride, and controlled radical polymerization of acrylamide. The surfaces were characterized by X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, ellipsometry, and contact-angle measurements.
View Article and Find Full Text PDFThis review presents the clinical background to abdominal wall reconstruction, the different types of surgical meshes employed and known mechanisms of infection. It is shown that there are major physico-chemical differences between available meshes, which, in combination with the location of the mesh, the surgical technique applied and hernia type involved influence the infection potential.
View Article and Find Full Text PDFThe antigen I/II family of surface proteins is expressed by most oral streptococci, including Streptococcus mutans, and mediates specific adhesion to, among other things, salivary films and extracellular matrix proteins. In this study we showed that antigen I/II-deficient S. mutans isogenic mutant IB03987 was nearly unable to adhere to laminin films under flow conditions due to a lack of specific interactions (0.
View Article and Find Full Text PDFPin tract infections of external fixators used in orthopaedic reconstructive bone surgery are serious complications that can eventually lead to periostitis and osteomyelitis. In vitro experiments have demonstrated that bacteria adhering to stainless steel in a biofilm mode of growth detach under the influence of small electric currents, while remaining bacteria become less viable upon current application. Therefore, we have investigated whether a 100microA electric current can prevent signs of clinical infection around percutaneous pins, implanted in the tibia of goats.
View Article and Find Full Text PDFMicro-implants are increasingly popular in clinical orthodontics to effect skeletal anchorage. However, biofilm formation on their surfaces and subsequent infection of peri-implant tissues can result in either exfoliation or surgical removal of these devices. The present study aimed to assess biofilm formation on five commercially available, surface characterized micro-implant systems in vitro.
View Article and Find Full Text PDFWaterborne diseases constitute a threat to public health despite costly treatment measures aimed at removing pathogenic microorganisms from potable water supplies. This paper compared the removal of Raoultella terrigena ATCC 33257 and Escherichia coli ATCC 25922 by negatively and positively charged types of activated carbon particles. Both strains display bimodal negative zeta-potential distributions in stabilized water.
View Article and Find Full Text PDFAntigen I/II can be found on streptococcal cell surfaces and is involved in their interaction with salivary proteins. In this paper, we determine the adsorption enthalpies of salivary proteins to Streptococcus mutans LT11 and S. mutans IB03987 with and without antigen I/II, respectively, using isothermal titration calorimetry.
View Article and Find Full Text PDFObjectives: The provision of antiplaque benefits to dentifrices assists patients in improving hygiene and reducing susceptibility to gingivitis and caries. Chemical plaque control involves different mechanisms and is mostly associated with antibacterial effects, but also includes effects on pellicle surface chemistry to improve cleansing or discourage renewed plaque formation. It is the aim of this paper to analyze in vitro detachment of co-aggregating oral actinomyces and streptococci from pellicle surfaces by dentifrice supernates and to study subsequent de novo streptococcal deposition.
View Article and Find Full Text PDFBacterial adhesion to and transfer between surfaces is a complicated process. With regard to the success of biomaterials implants, studies on bacterial adhesion and transfer should not be confined to biomaterials surfaces in the human body, but also encompass surfaces in the operating room, where the origin of many biomaterials related infections is found. The purpose of this study was to quantify the transfer of Staphylococcus aureus, Staphylococcus epidermidis, and Propionibacterium acnes from one operating room material to another, while accounting for surface hydrophobicity and roughness, moistness and application of friction during transfer.
View Article and Find Full Text PDFObjectives: Antibiotic-loaded bone cements are used for the permanent fixation of joint prostheses. Antibiotic-loaded cements significantly decrease the incidence of infection. The objective of this study was to investigate whether the viability of bacteria derived from patients with a prosthesis-related infection could be further decreased when antibiotic release from bone cements was combined with application of pulsed ultrasound.
View Article and Find Full Text PDFMost bacterial strains adhere poorly to poly(ethylene oxide) (PEO)-brush coatings, with the exception of a Pseudomonas aeruginosa strain. The aim of this study was to find factors determining whether P. aeruginosa strains do or do not adhere to a PEO-brush coating in a parallel plate flow chamber.
View Article and Find Full Text PDFClin Orthop Relat Res
November 2006
Intraoperative bacterial contamination increases risk for postoperative wound-healing problems and periprosthetic infection, but to what extent remains unclear. We asked whether bacterial contamination of the instruments and bone during primary prosthesis insertion was associated with prolonged wound discharge and subsequent periprosthetic infection. During 100 total hip arthroplasties, four intraoperative cultures were taken from the instruments and two portions of removed bone.
View Article and Find Full Text PDFCataract surgery is routinely performed to replace the clouded lens by a rigid polymeric intra-ocular lens unable to accommodate. By implanting a silicone gel into an intact capsular bag the accommodating properties of the natural lens can be maintained or enhanced. The implantation success of accommodating lenses is hampered by the occurrence of capsular opacification (PCO) due to lens epithelial cell (LEC) growth.
View Article and Find Full Text PDFPurpose: The aim of this study was to determine the effect of continuous wear on physicochemical surface properties of silicone hydrogel (S-H) lenses and their susceptibility to bacterial adhesion.
Methods: In this study, volunteers wore 2 pairs of either "lotrafilcon A" or "balafilcon A" S-H contact lenses. The first pair was worn continuously for a week and the second pair for 4 weeks.
J Biomed Mater Res B Appl Biomater
November 2006
Reprocessing of single-use devices is an upcoming issue in the Western world, but has been for many years in developing countries. In developing countries, the number of bone fractures due to traffic or industrial accidents is high. Patients often need an osteosynthesis with plates and screws, but most patients, however, cannot afford this because of the costs involved and have to rely on the application of used plates and screws.
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