Pseudogymnoascus destructans is a fungal pathogen responsible for a deadly disease among North American bats known as white-nose syndrome (WNS). Since detection of WNS in the United States in 2006, its rapid spread and high mortality has challenged development of treatment and prevention methods, a significant objective for wildlife management agencies. In an effort to mitigate precipitous declines in bat populations due to WNS, we have developed and implemented a multi-year mitigation strategy at Black Diamond Tunnel (BDT), Georgia, singly known as one of the most substantial winter colony sites for tricolored bats (Perimyotis subflavus), with pre-WNS abundance exceeding 5000 individuals.
View Article and Find Full Text PDFFungal pathogens are a growing worldwide concern. Declines in a number of economically and agriculturally important plant and animal species pose a significant threat to both biodiversity and food security. Although many effective antifungal agents have been identified, their toxicity often precludes their use with food products or sensitive animal species.
View Article and Find Full Text PDFBackground: The recently-identified causative agent of White-Nose Syndrome (WNS), Pseudogymnoascus destructans, has been responsible for the mortality of an estimated 5.5 million North American bats since its emergence in 2006. A primary focus of the National Response Plan, established by multiple state, federal and tribal agencies in 2011, was the identification of biological control options for WNS.
View Article and Find Full Text PDFThe recently identified causative agent of white-nose syndrome (WNS), Pseudogymnoascus destructans, has been implicated in the mortality of an estimated 5.5 million North American bats since its initial documentation in 2006 (Frick et al. in Science 329:679-682, 2010).
View Article and Find Full Text PDFJ Ind Microbiol Biotechnol
November 2012
Rhodococcus is an important industrial microorganism that possesses diverse metabolic capabilities; it also has a cell envelope, composed of an outer layer of mycolic acids and glycolipids. Selected Rhodococcus species when induced are capable of transforming nitriles to the corresponding amide by the enzyme nitrile hydratase (NHase), and subsequently to the corresponding acid via an amidase. This nitrile biochemistry has generated interest in using the rhodococci as biocatalysts.
View Article and Find Full Text PDFJ Ind Microbiol Biotechnol
February 2012
Fungal contamination of biomedical processes and facilities can result in major revenue loss and product delay. A biomedical research facility (BRF) culturing human cell lines experienced recurring fungal contamination of clean room incubators over a 3-year period. In 2010, as part of the plan to mitigate contamination, 20 fungal specimens were isolated by air and swab samples at various locations within the BRF.
View Article and Find Full Text PDFPurpose: To examine in vitro effects of evaporation and drying of multipurpose contact lens solutions on survival of Fusarium and Acanthamoeba.
Methods: Conidia of representative Fusarium from the 2004-2006 keratitis outbreak and trophozoites of Acanthamoeba castellanii were inoculated into commercially available multipurpose contact lens care solutions. These solutions were inoculated with 10(2)-10(6) microbial propagules/mL and were evaporated for at least 24 hours.
Purpose: To investigate the relative abilities of different haplotypes of the Fusarium solani (FSSC)-Fusarium oxysporum (FOSC) complexes to attach to and invade hydrogel contact lenses.
Methods: Silicone hydrogel and traditional hydroxyethylmethacrylate soft contact lenses were exposed to conidia [10 ml in phosphate-buffered saline (PBS)] of different haplotypes of fusaria associated with the Fusarium keratitis outbreak of 2004-2006. Select lenses and fungi were examined under conditions of organic enrichment.
Over the past several decades mycotic keratitis has been considered a rare sequel to hydrogel contact lens wear. In 2005--2006 an upswing in the incidence of Fusarium keratitis was associated with a disproportionate use of one multipurpose contact lens solution (MPS, ReNu with MoistureLoc, Bausch & Lomb, Rochester, NY). The MPS, as manufactured and marketed, was sterile and met regulatory guidelines for antimicrobial activity.
View Article and Find Full Text PDFPurpose: To examine in vitro conditions for attachment and penetration of silicone hydrogel (SH) lenses by clinical isolates of the Fusarium oxysporum-F. solani complexes and the relative susceptibilities of the fusaria in the lens matrices to multipurpose contact lens solutions (MPSs).
Methods: SH soft contact lenses were soaked in Sabouraud dextrose broth (SAB) for 2 hours and transferred to 3.
Purpose: To analyze the relative capacities of Fusarium solani and Ulocladium sp. to attach to and penetrate silicone hydrogel soft contact lenses.
Methods: Representative silicone hydrogel (SH, siloxy complexes) and conventional [hydroxyethylmethylacrylate (HEMA)] soft contact lenses were exposed to suspensions of F.
Purpose: To analyze factors implicating the association of ReNu with MoistureLoc (ReNu ML) multipurpose contact lens solution (MPS) with the increased incidence of Fusarium keratitis.
Methods: Used contact lens cases with and without contact lenses and MPS containers were collected from patients with confirmed or possible Fusarium keratitis. Direct microscopy including transparent adhesive tape preparations and swab cultures were used to determine fungal colonization.
Planktonic and attached cells of strains of Candida albicans, C. glabrata and C. krusei with varied susceptibilities to fluconazole (FCZ) were compared for their relative susceptibilities to Ag+ via cell recovery and flow cytometric analyses.
View Article and Find Full Text PDFPurpose: To compare lysozyme adsorption and absorption and bacterial adhesion interactions on conventional (etafilcon A) and silicone (balafilcon A) hydrogel contact lenses.
Method: Lysozyme concentrations and activities associated with the lenses were determined after solvent extraction (trifluoroacetic acid/acetonitrile) and directly on the lenses without extraction with micrococcal- and micro-bicinchoninic acid (BCA) assays. Cells of bacteria with radiolabeled leucine and a cell recovery procedure were used in determinations of bacterial adhesion to lenses.
High efficiency particulate arrestance (HEPA; 99.97% efficient at 0.3 microm) filters, filters with ASHRAE particulate arrestance rating of 90-95% at 1 mum (90-95% filters), and lower efficiency cellulosic-polyester filters from air conditioning systems in hospitals and commercial buildings were removed from the systems and examined microscopically for mold colonization.
View Article and Find Full Text PDFJ Ethnopharmacol
January 2005
The biological activities of the following four important medicinal plants of Balochistan, Pakistan were checked; Grewia erythraea Schwein f. (Tiliaceae), Hymenocrater sessilifolius Fisch. and C.
View Article and Find Full Text PDFAntimicrob Agents Chemother
September 2004
Wild-type and efflux pump-deficient cells of Candida albicans adhering to silicone were compared with planktonic cells by flow cytometry for their relative resistance to fluconazole (FCZ). Flow cytometry data on cells carrying a fusion of green fluorescent protein to efflux pump promoters confirmed that enhanced tolerance of attached cells to FCZ was due in part to increased expression of CaMDR1 and CDR1 promoters. Within 2 h of their attachment to silicone, the adherent cells demonstrated levels of FCZ tolerance shown by cells from 24-h biofilms.
View Article and Find Full Text PDFAntimicrob Agents Chemother
July 2002
The incidence of Acanthamoeba keratitis, a disease associated with contact lens wear, has been in apparent decline with the advent of multipurpose contact lens solutions. The concentrations of the biguanides chlorhexidine digluconate (CHX) and particularly polyhexamethylene biguanide (PHMB) included in multipurpose solutions (MPSs) are sublethal for amoebae. We evaluated by flow cytometry the effects of these two biguanides on phagocytosis of particles and the survival of trophozoites of Acanthamoeba castellanii and A.
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