Pentasilver hexaoxoiodate (AgIO) has broad-spectrum antimicrobial efficacy, including the long-term prevention of microbial adherence, the rapid killing of planktonic microorganisms, and the elimination of mature biofilms. This study's goal was to determine whether it may also have antiviral activity against structurally distinct viruses. AgIO was tested following ASTM E1052-20, Standard Practice to Assess the Activity of Microbicides Against Viruses in Suspension, against adenovirus type 5, murine norovirus, poliovirus type 1, SARS-CoV-2 (original), and SARS-CoV-2 (omicron) (host cells: H1HeLa, RAW 264.
View Article and Find Full Text PDFSolutions containing Ag nanoclusters, Ag, and higher oxidation state silver, generated from nanocrystalline silver dressings, were anti-inflammatory against porcine skin inflammation. The dressings have clinically-demonstrated broad-spectrum antimicrobial activity, suggesting application of nanosilver solutions in treating pulmonary infection. Nanosilver solutions were tested for antimicrobial efficacy; against HSV-1 and SARS-CoV-2; and nebulized in rats with acute pneumonia.
View Article and Find Full Text PDFBacterial wilt is a re-emerging disease on dry bean and can affect many other crop species within the Fabaceae. The causal agent, Curtobacterium flaccumfaciens pv. flaccumfaciens (CFF), is a small, Gram-positive, rodshaped bacterium that is seed-transmitted.
View Article and Find Full Text PDFFungi and bacteria cause disease issues in cultivated plants world-wide. In most cases, the fungi and bacteria colonize plant tissues as biofilms, which can be very challenging to destroy or eradicate. In this experiment, we employed a novel (biofilm) approach to crop disease management by evaluating the efficacies of six fungicides, and four silver-based compounds, versus biofilms formed by fungi and bacteria, respectively.
View Article and Find Full Text PDFBackground is provided on biofilms, including their formation, tolerance mechanisms, structure, and morphology within the context of chronic wounds. The features of biofilms in chronic wounds are discussed in detail, as is the impact of biofilm on wound chronicity. Difficulties associated with the use of standard susceptibility tests (minimum inhibitory concentrations or MICs) to determine appropriate treatment regimens for, or develop new treatments for use in, chronic wounds are discussed, with alternate test methods specific to biofilms being recommended.
View Article and Find Full Text PDFAdv Drug Deliv Rev
March 2017
Pre-clinical antimicrobial validation testing for single and combination products, and parameters that should be considered when testing the antimicrobial performance of a medical device, are discussed. Guidance is provided on key elements required for in vitro and in vivo antimicrobial validation, including validation of microbial growth, microbial recovery, neutralization, and antimicrobial activity. An important consideration, both in terms of practicality and economics, is designing in vitro studies that bridge to in vivo testing: A representative in vitro model is used to generate data on many clinically relevant microorganisms, and then one microorganism is selected for use in in vivo testing.
View Article and Find Full Text PDFThis work explores the unique antibiofilm activity of pentasilver hexaoxoiodate (Ag(5)IO(6)). To test this activity, wound dressings were impregnated with Ag(5)IO(6) and compared with various commercially available silver-containing dressings, as well as dressings containing chlorhexidine, iodine and polyhexamethylene biguanide (PHMB). The materials were tested against Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans for their ability to prevent micro-organism adherence, eliminate planktonic micro-organisms and disrupt/eliminate mature biofilms generated using the MBEC™ assay within 24 h of microbial exposure.
View Article and Find Full Text PDFPrevention and treatment of bacterial colonised/infected wounds are critical. Many commercially available silver dressings claim broad-spectrum bactericidal activity over days and are indicated for serious conditions including burns and ulcers. However, there is no peer-reviewed literature available for many newer dressings.
View Article and Find Full Text PDFThis study examined the mechanism of nanocrystalline silver antiinflammatory activity, and tested nanocrystalline silver for systemic antiinflammatory effects. Secondary ion mass spectroscopy of skin treated directly with nanocrystalline silver for 24 hours showed that at skin surfaces there were significant deposits at weights corresponding to Ag, AgO, AgCl, AgNO(3), Ag(2)O, and silver clusters Ag(2-6), but silver penetration was minimal. To test for translocation of the effect, a porcine contact dermatitis model in which wounds were induced on one side of the back and then treated with nanocrystalline silver on the opposite side of the back was used.
View Article and Find Full Text PDFBackground: Nanocrystalline silver dressings have anti-inflammatory activity, unlike solutions containing Ag+ only, which may be due to dissolution of multiple silver species. These dressings can only be used to treat surfaces. Thus, silver-containing solutions with nanocrystalline silver properties could be valuable for treating hard-to-dress surfaces and inflammatory conditions of the lungs and bowels.
View Article and Find Full Text PDFThe kinetics of nanocrystalline silver dressing heat treatment was investigated via isothermal heat treatments at 90 degrees C, 100 degrees C, and 110 degrees C lasting 2-50h. Bactericidal efficacy of the dressings was measured via log reductions, while bacteriostatic longevity was determined via plate-to-plate transfer corrected zones of inhibition. Morphological evolution of the dressing was studied by X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy, while changes in heat flow were measured by differential scanning calorimetry.
View Article and Find Full Text PDFThe anti-inflammatory activity of nanocrystalline silver was examined using a porcine model of contact dermatitis. Inflammation was induced with dinitrochlorobenzene and then treated daily with nanocrystalline silver dressings, 0.5% silver nitrate, or saline.
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