Endophthalmitis is an intraocular microbial infection that can lead to permanent blindness, even with prompt anti-microbial therapy. Multi-drug-resistant organisms are on the rise, potentially limiting the efficacy of current empiric antibiotic therapies of intravitreal ceftazidime and vancomycin. Cefiderocol is a recent FDA- and EMA-approved antibiotic for multi-drug-resistant Gram-negative bacteria.
View Article and Find Full Text PDFAn overlooked factor in the efficacy of topical antibiotics to treat bacterial keratitis is the state of the corneal epithelium. Recently, we evaluated topical cefiderocol for the treatment of extensively drug-resistant (XDR) (PA) keratitis in eyes with the corneal epithelium abraded. The goal of this study was to use the same model with the corneal epithelium left intact to evaluate the efficacy of cefiderocol and other antibiotics and compare the results to those of the previous study.
View Article and Find Full Text PDFPurpose: To test cefiderocol, a siderophore-cephalosporin antibiotic for topical monotherapy treatment of experimental extensively drug-resistant (XDR) keratitis.
Design: Preclinical study.
Subjects And Controls: Deidentified keratitis isolates, XDR from eye drop outbreak, rabbits, saline, cefiderocol 50 mg/ml, ciprofloxacin 0.
Endogenous endophthalmitis caused by Gram-negative bacteria is an intra-ocular infection that can rapidly progress to irreversible loss of vision. While most endophthalmitis isolates are susceptible to antibiotic therapy, the emergence of resistant bacteria necessitates alternative approaches to combat intraocular bacterial proliferation. In this study the ability of predatory bacteria to limit intraocular growth of , , and was evaluated in a New Zealand white rabbit endophthalmitis prevention model.
View Article and Find Full Text PDFFront Cell Infect Microbiol
December 2023
Introduction: causes vision threatening keratitis. The transcription factor regulates virulence factors in response to the quorum sensing molecule N-3-oxo-dodecanoyl-L-homoserine lactone. isolates with mutations are characterized by an iridescent high sheen phenotype caused by a build-up of 2-heptyl-4-quinolone.
View Article and Find Full Text PDFEndogenous endophthalmitis caused by Gram-negative bacteria is an intra-ocular infection that can rapidly progress to irreversible loss of vision. While most endophthalmitis isolates are susceptible to antibiotic therapy, the emergence of resistant bacteria necessitates alternative approaches to combat intraocular bacterial proliferation. In this study the ability of predatory bacteria to limit intraocular growth of , , and was evaluated in a New Zealand White rabbit endophthalmitis prevention model.
View Article and Find Full Text PDFPurpose: To test cefiderocol, a siderophore-cephalosporin antibiotic for topical monotherapy treatment of experimental extensively drug resistant (XDR) keratitis.
Design: Preclinical study.
Subjects And Controls: Deidentified keratitis isolates, XDR from eye drop outbreak, rabbits, saline, cefiderocol 50 mg/ml, ciprofloxacin 0.
causes severe vision threatening keratitis. LasR is a transcription factor that regulates virulence associated genes in response to the quorum sensing molecule N-3-oxo-dodecanoyl-L-homoserine lactone. isolates with mutations are characterized by an iridescent high sheen phenotype caused by a build-up of 2-heptyl-4-quinolone.
View Article and Find Full Text PDFAdenoviruses are the major cause of ocular viral infections worldwide. Currently, there is no approved antiviral treatment for these eye infections. Cyclopentenylcytosine (CPE-C) is an antiviral that has demonstrated activity against more than 20 viruses.
View Article and Find Full Text PDFPurpose: Pseudomonas aeruginosa keratitis is a severe ocular infection that can lead to perforation of the cornea. In this study we evaluated the role of bacterial quorum sensing in generating corneal perforation and bacterial proliferation and tested whether co-injection of the predatory bacteria Bdellovibrio bacteriovorus could alter the clinical outcome. P.
View Article and Find Full Text PDFBiologics are almost exclusively administered systemically, but localized delivery is preferable as it minimizes off-target exposure and allows more aggressive treatments. Topical application of biologics to epithelia is generally ineffective because most are covered with fluids and biologics are washed out too quickly to have significant therapeutic effects. Here we explore the idea that attaching a binding domain can serve as an "anchor" to extend the residency time of biologics on wet epithelia, allowing their effective use even with infrequent applications.
View Article and Find Full Text PDFPurpose: keratitis is a severe ocular infection that can lead to perforation of the cornea. In this study we evaluated the role of bacterial quorum sensing in generating corneal perforation and bacterial proliferation and tested whether co-injection of the predatory bacteria could alter the clinical outcome. with mutations were observed among keratitis isolates from a study collecting samples from India, so an isogenic mutant strain of was included.
View Article and Find Full Text PDFTopic: Understanding approaches to sustainability in cataract surgery and their risks and benefits.
Clinical Relevance: In the United States, health care is responsible for approximately 8.5% of greenhouse gas (GHG), and cataract surgery is one of the most commonly performed surgical procedures.
Adenovirus ocular infections are common ocular viral infections seen worldwide, for which there is no approved antiviral therapy available. Ranpirnase is a novel ribonuclease which preferentially degrades tRNA resulting in an inhibition of protein synthesis. The study goal was to determine the anti-adenoviral activity of topical formulations of ranpirnase (OKG-0301) on adenoviral replication in the Ad5/NZW rabbit ocular replication model.
View Article and Find Full Text PDFBacterial stress response signaling systems, like the Rcs system are triggered by membrane and cell wall damaging compounds, including antibiotics and immune system factors. These regulatory systems help bacteria survive envelope stress by altering the transcriptome resulting in protective phenotypic changes that may also influence the virulence of the bacterium. This study investigated the role of the Rcs stress response system using a clinical keratitis isolate of Serratia marcescens with a mutation in the gene.
View Article and Find Full Text PDFMedical textiles are subject to particularly harsh disinfection procedures in healthcare settings where exposure risks are high. This work demonstrates a fabric treatment consisting of a reactive silver ink and low surface energy PDMS polymer that provides for superhydrophobicity and antiviral properties against enveloped herpes simplex virus stocks even after extended ultrasonic bleach washing. The antiviral properties of reactive silver ink has not been previously reported or compared with silver nanoparticles.
View Article and Find Full Text PDFPurpose: Presently, there is no approved antiviral therapy for adenovirus (HAdV) ocular infections. During the COVID-19 pandemic, increased attention has been focused on antiviral treatments. Remdesivir, hydroxychloroquine, ivermectin, and umifenovir (Arbidol) have been touted as potential antiviral treatments for COVID-19.
View Article and Find Full Text PDFAntibiotics (Basel)
February 2022
The treatment of eye infections is very different than treating other body infections that require systemic anti-infectives. Endophthalmitis, keratitis, conjunctivitis, and other ocular infections are treated with direct injection and with topical drops directly to the infection site. There are no anti-infective susceptibility standards to interpret treatment success, but the systemic standards can be used to guide ocular therapy if the concentration of anti-infective in the ocular tissue is assumed to be higher than the concentration in the blood serum.
View Article and Find Full Text PDFPurpose: Females and males respond differently to a number of systemic viral infections. Differences between females and males with respect to the severity of keratitis caused by Gram-negative bacteria such as are less well established.
Methods: In this study, we injected female and male New Zealand White rabbit corneas with a keratitis isolate of and evaluated the eyes after 48 hours for a number of clinical and microbiological parameters.
J Chromatogr B Analyt Technol Biomed Life Sci
November 2021
Besifloxacin has been embraced for the treatment of ocular bacterial infections. While LC-MS/MS has been used in investigating BSF pharmacokinetics, those costly instruments are not universally available and have complicated requirements for operation and maintenance. Additionally, pharmacokinetics of besifloxacin in dose-intense regimens are still unknown.
View Article and Find Full Text PDFThe Rcs phosphorelay is a bacterial stress response system that responds to envelope stresses and in turn controls several virulence-associated pathways, including capsule, flagella, and toxin biosynthesis, of numerous bacterial species. The Rcs system also affects antibiotic tolerance, biofilm formation, and horizontal gene transfer. The Rcs system of the ocular bacterial pathogen was recently demonstrated to influence ocular pathogenesis in a rabbit model of keratitis, with Rcs-defective mutants causing greater pathology and Rcs-activated strains demonstrating reduced inflammation.
View Article and Find Full Text PDFPurpose: Prophylactic topical antiseptics used to eliminate bacteria on the ocular surface prior to ocular surgery should be both effective and non-irritating. Five percent povidone iodine (PI) is an accepted antiseptic used for prophylaxis. Dilute 2.
View Article and Find Full Text PDFIt was previously demonstrated that predatory bacteria are able to efficiently eliminate Gram-negative pathogens including antibiotic-resistant and biofilm-associated bacteria. In this proof-of-concept study we evaluated whether two species of predatory bacteria, and , were able to alter the survival of Gram-negative pathogens on the ocular surface. Clinical keratitis isolates of (strain PAC) and (strain K904) were applied to the ocular surface of NZW rabbits followed by application of predatory bacteria.
View Article and Find Full Text PDFCoagulase-negative staphylococci (CoNS) are frequently occurring ocular opportunistic pathogens that are not easily identifiable to the species level. The goal of this study was to speciate CoNS and document antibiotic susceptibilities from cases of endophthalmitis ( = 50), keratitis ( = 50), and conjunctivitis/blepharitis ( = 50) for empiric therapy. All 150 isolates of CoNS were speciated using (1) API Staph (biochemical system), (2) Biolog GEN III Microplates (phenotypic substrate system), and (3) DNA sequencing of the gene.
View Article and Find Full Text PDFThere is no approved antiviral therapy for adenovirus (HAdV) ocular infections. Astodrimer sodium (SPL7013) is a polyanionic dendrimer with antiviral activity. The current study evaluated the ocular tolerability and anti-adenoviral efficacy of topical SPL7013 in rabbit ocular models.
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