Browsing by Author "Elkashif, Ahmed"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Investigation of auranofin and gold-containing analogues antibacterial activity against multidrug-resistant Neisseria gonorrhoeae
    Elkashif, Ahmed; Seleem, Mohamed N. (Nature Publishing Group, 2020-03-27)
    Neisseria gonorrhoeae represents an urgent public health threat due to the rapid emergence of resistance to current antibiotics and the limited number of anti-gonococcal agents currently in clinical trials. This study utilized a drug repositioning strategy to investigate FDA-approved gold-containing drugs against N. gonorrhoeae. Auranofin, sodium aurothiomalate and aurothioglucose inhibited 48 clinical isolates of N. gonorrhoeae including multidrug-resistant strains at a concentration as low as 0.03 µg/mL. A time-kill assay revealed that auranofin exhibited rapid bactericidal activity against N. gonorrhoeae. Moreover, both sodium aurothiomalate and aurothioglucose did not inhibit growth of vaginal protective commensal lactobacilli. Auranofin, in combination with azithromycin, ceftriaxone, cefixime or tetracycline showed an additive effect against four N. gonorrhoeae strains, suggesting the possibility of using auranofin in dual therapy. Moreover, auranofin reduced the burden of intracellular N. gonorrhoeae by over 99% outperforming the drug of choice ceftriaxone. Auranofin was found superior to ceftriaxone in reducing the secretion of the pro-inflammatory cytokine IL-8 by endocervical cells infected with N. gonorrhoeae. Furthermore, auranofin exhibited a prolonged post-antibiotic effect over 10 h, as well as inability to generate resistant mutants. Overall, the current study suggests that repurposing gold-containing drugs, like auranofin, for treatment of gonorrhea warrants further investigation.
  • Thumbnail Image
    Wearable and Flexible Ozone Generating System for Treatment of Infected Dermal Wounds
    Roth, Alexander; Elkashif, Ahmed; Selyamani, Vidhya; Stucky, Rachel Abigail; Seleem, Mohamed N.; Ziaie, Babak; Rahimi, Rahim (Frontiers, 2020-05-19)
    Wound-associated infections are a significant and rising health concern throughout the world owing to aging population, prevalence of diabetes, and obesity. In addition, the rapid increase of life-threatening antibiotic resistant infections has resulted in challenging wound complications with limited choices of effective therapeutics. Recently, topical ozone therapy has shown to be a promising alternative approach for treatment of non-healing and infected wounds by providing strong antibacterial properties while stimulating the local tissue repair and regeneration. However, utilization of ozone as a treatment for infected wounds has been challenging thus far due to the need for large equipment usable only in contained, clinical settings. This work reports on the development of a portable topical ozone therapy system comprised of a flexible and disposable semipermeable dressing connected to a portable and reusable ozone-generating unit via a flexible tube. The dressing consists of a multilayered structure with gradient porosities to achieve uniform ozone distribution. The effective bactericidal properties of the ozone delivery platform were confirmed with two of the most commonly pathogenic bacteria found in wound infections, Pseudomonas aeruginosa and Staphylococcus epidermidis. Furthermore, cytotoxicity tests with human fibroblasts cells indicated no adverse effects on human cells.