Publications by authors named "Richard A Hull"

Aims: Since management of catheter-associated infections, which are generally biofilm-based, is attempted in certain patients such as older and frail patients by using a catheter lock solution (CLS), we examined the combination of N-acetyl cysteine (NAC), an antibiofilm agent, and levofloxacin, a broad-spectrum antimicrobial agent, for this purpose.

Methods And Results: Intravascular catheters were colonized with methicillin-resistant Staphylococcus epidermidis, levofloxacin-sensitive/methicillin-resistant Staph. aureus, levofloxacin-resistant/methicillin-resistant Staph.

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Unlabelled: Bacterial interference using non-pathogenic Escherichia coli 83972 is a novel strategy for preventing catheter-associated urinary tract infection (CAUTI). Crucial to the success of this strategy is to establish a high coverage and stable biofilm of the non-pathogenic bacteria on the catheter surface. However, this non-pathogenic strain is sluggish to form biofilms on silicone as the most widely used material for urinary catheters.

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Catheter-associated infections can cause severe complications and even death. Effective antimicrobial modification of catheters that can prevent device colonization has the potential of preventing clinical infection. We studied in vitro the antimicrobial activities of central venous catheters impregnated with N-acetylcysteine (NAC), an antibiofilm agent, and a broad-spectrum antibiotic against a range of important clinical pathogens.

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Objectives: To compare the effectiveness of bacterial interference versus placebo in preventing urinary tract infection (UTI).

Methods: The main outcome measure was the numbers of episodes of UTI/patient-year. Randomization was computer generated, with allocation concealment by visibly indistinguishable products distributed from a core facility.

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Background: In vitro, urinary catheter colonization by avirulent Escherichia coli 83972 impedes subsequent catheter colonization by a variety of uropathogenic organisms. However, E. coli 83972 shows a low efficacy of adherence to silicone urinary catheter material, possibly because the fim operon encoding adhesive type 1 fimbriae is incomplete.

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We investigated whether insertion of urinary catheters that had been coated with Escherichia coli HU2117 could establish bladder colonization with this nonvirulent organism. Ten of 12 subjects were successfully colonized for 14 days or more. The rate of symptomatic UTI during colonization was 0.

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This prospective, randomized, placebo-controlled, double-blind pilot trial examined the efficacy of bacterial interference in preventing urinary tract infection (UTI) in 27 patients with spinal cord injury. Patients whose bladders became colonized with Escherichia coli 83972 were half as likely (P=.01) than noncolonized patients to develop UTI during the subsequent year.

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Objectives: Natural microbial defence systems, such as bacteriocins, may be a novel means to prevent catheter-associated urinary tract infection. We investigated in vitro whether a colicin-expressing strain of Escherichia coli could prevent urinary catheter colonization by a colicin-susceptible, uropathgenic strain of E. coli.

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Purpose Of Review: The underlying cause of catheter-associated urinary tract infection is biofilm formation by uropathogens on the urinary catheter. Biofilm is a relatively new concept in medicine, and current measures to prevent biofilm formation are inadequate. Considerable work is being done in this area, but little clinical progress has been made.

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Objectives: The presence of a nonpathogenic organism on the surface of a urinary catheter might impede catheter colonization by pathogens and thus prevent urinary tract infection. Previously, we reported that preinoculating urinary catheters with a nonpathogenic strain of Escherichia coli (83972) significantly impeded catheter colonization in vitro by gram-positive bacteria (Enterococcus faecalis). To explore this phenomenon further, we investigated in vitro whether E.

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Recent clinical studies suggest that the deliberate colonization of the human bladder with a prototypic asymptomatic bacteriuria-associated bacterium, Escherichia coli 83972, may reduce the frequency of urinary tract infection in individuals with spinal cord injuries. However, the mechanism by which E. coli 83972 colonizes the bladder is unknown.

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Purpose: The capacity of a preexisting coating of Escherichia coli 83972 to reduce catheter colonization by Enterococcus faecalis 210 was investigated. Enterococcus was chosen for these trials since it is a common urinary pathogen in patients with an indwelling urinary catheter.

Materials And Methods: Each experiment tested 3 growth conditions.

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