While urinary tract infections (UTIs) are often suspected on the basis of clinical symptoms and the finding of pyuria on urinalysis, the documentation of a bacterial UTI is based on the significant growth ofa uropathogen on an agar medium incubated at 35-37 degrees C. The recommended length of time for incubation has ranged from 24 to 48 hours. We present a case of a UTI associated with the slow-growing, gram-negative organism, Oligella ureolytica which was finally documented after incubation of an agar medium for more than 48 hours.
View Article and Find Full Text PDFThis paper demonstrates the effectiveness of a new antimicrobial suture coating. An amphiphilic polymer, poly[(aminoethyl methacrylate)-co-(butyl methacrylate)] (PAMBM), inspired by antimicrobial peptides, was bactericidal against S. aureus in time-kill experiments.
View Article and Find Full Text PDFThis study investigated the initial adhesion of Staphylococcus aureus from flowing buffer onto modified albumin films with the objective of probing the influence of electrostatic heterogeneity on bacterial adhesion. Electrostatic heterogeneity, on the lengthscale of 10-100 nm, was incorporated into the protein film through the irreversible random deposition of small amounts of polycation coils to produce isolated positive "patches" on the otherwise negative albumin surface before exposure to bacteria, which also possess a net negative surface charge. The system was benchmarked against an appropriate analog using 1 microm silica spheres and the same cationic patches on a silica substrate.
View Article and Find Full Text PDFA direct comparison of two strategies for designing antimicrobial polymers is presented. Previously, we published several reports on the use of facially amphiphilic (FA) monomers which led to polynorbornenes with excellent antimicrobial activities and selectivities. Our polymers obtained by copolymerization of structurally similar segregated monomers, in which cationic and non-polar moieties reside on separate repeat units, led to polymers with less pronounced activities.
View Article and Find Full Text PDFPolyguanidinium oxanorbornene ( PGON) was synthesized from norbornene monomers via ring-opening metathesis polymerization. This polymer was observed to be strongly antibacterial against Gram-negative and Gram-positive bacteria as well as nonhemolytic against human red blood cells. Time-kill studies indicated that this polymer is lethal and not just bacteriostatic.
View Article and Find Full Text PDFAntimicrobial polynorbornenes composed of facially amphiphilic monomers have been previously reported to accurately emulate the antimicrobial activity of natural host-defense peptides (HDPs). The lethal mechanism of most HDPs involves binding to the membrane surface of bacteria leading to compromised phospholipid bilayers. In this paper, the interactions between biomimetic vesicle membranes and these cationic antimicrobial polynorbornenes are reported.
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