Publications by authors named "Emma B Hume"

Staphylococcus aureus is a common bacterial isolate from cases of microbial keratitis. The virulence factors that contribute to its pathogenicity during this disease have not been fully resolved. The aim of the current study was to examine the effects of the extracellular protease Staphopain A on corneal virulence.

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Staphylococcus is a leading cause of microbial keratitis, characterized by destruction of the cornea by bacterial exoproteins and host-associated factors. The aim of this study was to compare extracellular and cell-associated proteins produced by two different isolates of S. aureus, a virulent clinical isolate (Staph 38) and a laboratory strain (Staphylococcus aureus 8325-4) of weaker virulence in the mouse keratitis model.

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Staphylococcus aureus is a leading cause of corneal infection. CXC receptor 2 binding chemokines have been implicated in the pathogenesis of Pseudomonas aeruginosa keratitis. The role of this receptor in immune responses during Staphylococcus keratitis remains to be fully understood.

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Purpose: One strategy to minimize bacteria-associated adverse responses such as microbial keratitis, contact lens-induced acute red eye (CLARE), and contact lens induced peripheral ulcers (CLPUs) that occur with contact lens wear is the development of an antimicrobial or antiadhesive contact lens. Cationic peptides represent a novel approach for the development of antimicrobial lenses.

Methods: A novel cationic peptide, melimine, was covalently incorporated into silicone hydrogel lenses.

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Purpose: To compare the disinfecting efficacy of five soft contact lens multipurpose disinfection solutions (MPDS) against Fusarium solani clinical isolates and the ISO standard ATCC 36031 strain.

Methods: Three commercially available and two recalled MPDS were tested using the ISO/CD 14,729 stand-alone test for contact lens care products against 10 ocular isolates of F. solani and the ATCC 36031 strain.

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Background: Staphylococcus is the leading cause of microbial keratitis. Staphylococcus aureus isolated from ocular infections with resistance to a wide range of antibiotics, including the commonly prescribed fluoroquinolones, is emerging. The aim of this study was to determine the current antibiotic susceptibilities of ocular S.

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Purpose: To compare the susceptibilities of clinical isolates of Serratia marcescens and the standard ISO ATCC 13880 strain to five contact lens multipurpose disinfection solutions (MPDSs).

Methods: Five commercially available MPDSs, containing either a polymeric biguanide or polyquaternium, were tested using ISO/CD 14729 stand-alone test for contact lens care products against four ocular isolates of S. marcescens and the strain ATCC 13880.

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Interleukin-4 (IL-4) has previously been implicated in a protective response to Staphylococcus aureus corneal infection. Consequently, the specific role of IL-4 during S. aureus corneal infection was investigated using IL-4 gene knockout mice.

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Corneal vascularisation is a potentially devastating occurrence that can cause blindness. Currently, treatments for this condition are limited. In these studies, we have investigated a novel inhibitor of angiogenesis, 12-methyl tetradecanoic acid (12-MTA), to treat corneal vascularisation in mouse models of corneal alkali injury and corneal Pseudomonas aeruginosa infection.

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Purpose: To determine whether interleukin-6 (IL-6) plays a protective role in Staphylococcus aureus keratitis in a gene knockout (gko) mouse model and to determine whether IL-6 may be used as a therapy to modulate host responses and control bacterial infection, thereby reducing scarring.

Methods: The eyes of IL-6 gko mice and wild-type mice were challenged topically with S. aureus and examined at 24 hours after infection.

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Pseudomonas is one of the leading causes of contact lens-related microbial keratitis. Despite the use of antibiotics, the host inflammatory response continues to cause damage to the cornea, which may lead to blindness. CXCR2-binding chemokines have been implicated in the pathogenesis of Pseudomonas keratitis, and the exact role of this receptor remains to be elucidated.

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Staphylococcus is a leading cause of the potentially blinding disease microbial keratitis. Even with the use of antibiotic therapy, the host inflammatory response continues to damage the cornea, which may lead to blindness. Manipulation of the host response may help improve patient outcome from this devastating disease.

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Purpose: Secretory phospholipase A2 (sPLA2) is a potent antibacterial enzyme in tears and has been found to kill Staphylococcus aureus rapidly in vitro. The purpose was to determine whether sPLA2 deposition is associated with contact lens (CL) type, if sPLA2 remains active on CLs, and if this has an effect on bacterial adhesion.

Methods: Ionic (etafilcon A) and nonionic (Polymacon) high-water, soft CLs were used.

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Purpose: Contact lens contamination by Serratia marcescens can lead to the development of microbial keratitis and contact lens-induced acute red eye, particularly during overnight contact lens wear. The aim of this study was to investigate the interaction of S. marcescens with polymorphonuclear leukocytes (PMNs), which occur in closed-eye tears.

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Purpose: The purpose of this study was to determine the effectiveness of mupirocin and polymyxin B, alone and in combination, in vitro and in vivo using rabbit models of, and keratitis.

Methods: Rabbit eyes were intrastromally injected with 1,000 colony-forming units (CFUs) of or or 100 CFUs of Rabbits were then treated with 2.7 mg/mL mupirocin, 10,000 U/mL polymyxin B, a mupirocin:polymyxin B combination, or 0.

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Purpose: To determine the pathogenic role of gamma- and alpha-toxin in a rabbit model of Staphylococcus aureus keratitis.

Methods: S. aureus strains Newman (expressing gamma-toxin), Newman Delta(hlg) (deficient in gamma-toxin), Newman Delta(hlg)/pCU1 hlg(+) (chromosomal gamma-toxin-deficient mutant rescued by a plasmid encoding gamma-toxin), and Newman Delta(hla) (alpha-toxin-deficient) were intrastromally injected into rabbit corneas.

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