Search results for "Bacterial Adhesion"
showing 10 items of 48 documents
Effect of two prophylaxis methods on adherence of Streptococcus mutans to microfilled composite resin and giomer surfaces
2010
Objectives: Surface attributes of a restoration play an important role in adherence of plaque bacteria. Prophylaxis methods may be involved in modification of or damaging the restoration surface. The aim of the present study was to evaluate the effect of two prophylaxis methods on adherence of Streptococcus mutans to the surface of two restorative materials. Study design: A total of 60 specimens were prepared from each material; a microfilled composite resin (HelioProgress) and a giomer (Beautifil II). For each material, the specimens were randomly divided into three groups (n=20). Group 1: no prophylaxis treatment (control); Group 2: prophylaxis with pumice and rubber cup; Group 3: prophyl…
Host glycoprotein Gp96 and scavenger receptor SREC interact with PorB of disseminating Neisseria gonorrhoeae in an epithelial invasion pathway.
2007
Neisseria gonorrhoeae expresses numerous surface proteins that mediate bacterial adherence and invasion during infection. Gonococci expressing serotype A of the major outer membrane porin PorB (PorB(IA)) are frequently isolated from patients with severe disseminating infections. PorB(IA) triggers efficient adherence and invasion under low phosphate conditions mimicking systemic bloodstream infections. Here, we identify the human heat shock glycoprotein Gp96 and the scavenger receptor SREC as PorB(IA)-specific receptors. Gonococci expressing PorB(IA), but not those expressing PorB serotype B instead, bind to purified native or recombinant Gp96. Depletion of Gp96 from host cells prevented adh…
Towards Laser-Textured Antibacterial Surfaces
2018
AbstractEscherichia coli and Staphylococcus aureus bacterial retention on mirror-polished and ultrashort pulse laser-textured surfaces is quantified with a new approach based on ISO standards for measurement of antibacterial performance. It is shown that both wettability and surface morphology influence antibacterial behavior, with neither superhydrophobicity nor low surface roughness alone sufficient for reducing initial retention of either tested cell type. Surface structures comprising spikes, laser-induced periodic surface structures (LIPSS) and nano-pillars are produced with 1030 nm wavelength 350 fs laser pulses of energy 19.1 μJ, 1.01 μJ and 1.46 μJ, respectively. SEM analysis, optic…
Pyrrolomycins as potential anti-staphylococcal biofilms agents
2010
With the goal of discovering new anti-infective agents active against microbial biofilms, this investigation focused on some natural pyrrolomycins, a family of halogenated pyrrole antibiotics. In this study the anti-staphylococcal biofilm activity of pyrrolomycins C, D, F1, F2a, F2b, F3 and of the synthesized related compounds I, II, III were investigated. The susceptibility of six staphylococcal biofilms was determined by methyltiazotetrazolium staining. Most of the compounds were active at concentrations of 1.5 microg ml(-1) with significant inhibition percentages. A few of the compounds were active at the lowest screening concentration of 0.045 microg ml(-1). The population log reduction…
In vitro anti-biofilm activity of Boswellia spp. oleogum resin essential oils
2009
Aims: To evaluate the anti-biofilm activity of the commercially available essential oils from two Boswellia species. Methods and Results: The susceptibility of staphylococcal and Candida albicans biofilms was determined by methyltiazotetrazolium (MTT) staining. At concentrations ranging from 217·3 μg ml−1 (25% v/v) to 6·8 μg ml−1 (0·75% v/v), the essential oil of Boswellia papyrifera showed considerable activity against both Staphylococcus epidermidis DSM 3269 and Staphylococcus aureus ATCC 29213 biofilms. The anti-microbial efficacy of this oil against S. epidermidis RP62A biofilms was also tested using live/dead staining in combination with fluorescence microscopy, and we observed that …
A POLYCARBOXYLIC/AMINO FUNCTIONALIZED HYALURONIC ACID DERIVATIVE FOR THE PRODUCTION OF pH SENSIBLE HYDROGELS IN THE PREVENTION OF BACTERIAL ADHESION …
2014
A graft copolymer derivative of hyaluronic acid bearing pendant amino and short polymethacrylate portions (HA-EDA-BMP-MANa) has been employed for the production of a pH sensible vancomycin releasing hydrogel and studied in vitro to test its potential anti adhesive property against Staphylococcus aureus colonization. The copolymer obtained through atom transfer radical polymerization bears chargeable (carboxyl and amino groups) portions and it could be formulated as a hydrogel at a concentration of 10% w/v. The HA-EDA-BMP-MANa hydrogels, produced at three different pH values (5, 6 and 7, respectively), were formulated with or without the addition of vancomycin (2% w/v). The vancomycin releas…
A Silicone Ventricular Catheter Coated with a Combination of Rifampin and Trimethoprim for the Prevention of Catheter-related Infections
1998
So-called antiinfective catheters which are generated by incorporation of antimicrobial substances into polymers appear to be effectful devices in the prevention of catheter related infections. Such devices mainly act by prevention of bacterial colonization of the catheter surface rather than by inhibition of adherence. In a preceding study, we developed a rifampin-containing silicone catheter for the prevention of ventricular shunt infection. In the present study, this work was continued with a combination of antimicrobials incorporated in silicone ventricular catheters to reduce the risk of rifampin resistance and to expand the antimicrobial spectrum. We found that the drug release kineti…
The hemagglutinin of Staphylococcus saprophyticus is a major adhesin for uroepithelial cells.
1996
The 160-kDa hemagglutinin of Staphylococcus saprophyticus also serves as a fibronectin-binding protein, and the two activities may be present on different parts of the molecule. Bacteria expressing the 160-kDa hemagglutinin bound in large numbers to histological sections of human ureters, whereas nonhemagglutinating bacteria did not bind. Binding was decreased by an antiserum to the 160-kDa protein and by a preparation of sheep erythrocyte membranes. Fibronectin had no effect. We therefore conclude that binding of S. saprophyticus to uroepithelial cells is mediated by the hemagglutinating activity of the 160-kDa surface protein.
Control of biofilm formation by poly-ethylene-co-vinyl acetate films incorporating nisin.
2010
The aim of this study was to evaluate the effect of poly-ethylene-co-vinyl acetate (EVA) films incorporating different concentrations (0.1%, 0.5% and 1%) of nisin on the biofilm-forming ability of Listeria monocytogenes ATCC 7644, Staphylococcus aureus 815 and Staphylococ-cus epidermidis ATCC 35984. Nisin was incorporated into two grades of EVA (EVA14 and EVA28) in the melt during a common film-blowing operation. The efficacy of EVA/nisin films was evaluated by biofilm biomass measurements and Live/Dead staining in combination with fluorescence microscopy. In order to evaluate whether the nisin incorporation could modify the film surface properties, contact angle measurements and scanning e…
Role of tir and intimin in the virulence of rabbit enteropathogenic Escherichia coli serotype O103:H2.
2000
ABSTRACT Attaching and effacing (A/E) rabbit enteropathogenic Escherichia coli (REPEC) strains belonging to serogroup O103 are an important cause of diarrhea in weaned rabbits. Like human EPEC strains, they possess the locus of enterocyte effacement clustering the genes involved in the formation of the A/E lesions. In addition, pathogenic REPEC O103 strains produce an Esp-dependent but Eae (intimin)-independent alteration of the host cell cytoskeleton characterized by the formation of focal adhesion complexes and the reorganization of the actin cytoskeleton into bundles of stress fibers. To investigate the role of intimin and its translocated coreceptor (Tir) in the pathogenicity of REPEC, …