Med Mycol
November 2024
Microb Pathog
November 2024
invasive candidiasis is considered a global health problem. In such cases, biofilm formation on implanted devices represents a therapeutic challenge and the presence of metabolically inactive persistent cells (PCs) in these communities increases their tolerance to fungicidal drugs. This study investigated the influence of amoxicillin, AMX; cefepime, CEF; gentamicin, GEN; amikacin, AMK; vancomycin, VAN; and ciprofloxacin, CIP; on the production of PCs in biofilms of bloodstream isolates.
View Article and Find Full Text PDFTo evaluate the action of promethazine, fluoxetine and carbonyl cyanide 3-chlorophenylhydrazone as efflux pump inhibitors (EPIs) against multidrug-resistant . The effect of the compounds was evaluated in planktonic cells and bacterial biofilms. Accumulation tests were performed with ethidium bromide to prove their action as EPIs.
View Article and Find Full Text PDFJ Med Microbiol
March 2024
Cryptococcal biofilms have been associated with persistent infections and antifungal resistance. Therefore, strategies, such as the association of natural compounds and antifungal drugs, have been applied for the prevention of biofilm growth. Moreover, the pathogenicity model has been used to investigate the capacity to inhibit the pathogenicity of .
View Article and Find Full Text PDFThis study evaluated the antibiofilm activity of promethazine, deferiprone, and Manuka honey against Staphylococcus aureus and Pseudomonas aeruginosa in vitro and ex vivo in a wound model on porcine skin. The minimum inhibitory concentrations (MICs) and the effects of the compounds on biofilms were evaluated. Then, counting colony-forming units (CFUs) and confocal microscopy were performed on biofilms cultivated on porcine skin for evaluation of the compounds.
View Article and Find Full Text PDFThis study evaluated the antimicrobial activity of promethazine against , and and its effect on the antimicrobial susceptibility of biofilms grown and on porcine heart valves. Promethazine was evaluated alone and in combination with vancomycin and oxacillin against spp. and vancomycin and ceftriaxone against in planktonic form and biofilms grown and .
View Article and Find Full Text PDFJ Microbiol Methods
May 2023
Ex vivo experiments have been performed aiming at mimicking in vivo environments. The main aim of this research was to standardize in vitro dual-species biofilm formation by Staphylococcus pseudintermedius and Malassezia pachydermatis as a strategy to establish an ex vivo biofilm model. Initially, the in vitro formation of biofilms in co-culture was established, using YPD medium, inoculum turbidity of 0.
View Article and Find Full Text PDFThis study evaluated the effect of the iron chelator deferiprone (DFP) on antimicrobial susceptibility and biofilm formation and maintenance by . Planktonic susceptibility to DFP alone and in combination with antibiotics was evaluated by broth microdilution and biofilm metabolic activity was determined with resazurin. DFP minimum inhibitory concentration (MIC) range was 4-64 µg/mL and in combination reduced the MIC for amoxicillin/clavulanate and meropenem.
View Article and Find Full Text PDFFreshwater cetaceans play a significant role as sentinel animals, providing important data on animal species and aquatic ecosystem health. They also may serve as potential reservoirs of emerging pathogens and host virulence genes in their microbiota. In this study, we evaluated virulence factors produced by Gram-negative bacteria recovered from individuals belonging to two populations of free-ranging Amazon river dolphins (Inia geoffrensis).
View Article and Find Full Text PDFLett Appl Microbiol
March 2023
This study aimed to standardize the use of an ex vivo wound model for the evaluation of compounds with antibiofilm activity. The in vitro susceptibility of Staphylococcus aureus ATCC 29213 and Pseudomonas aeruginosa ATCC 27853 to ciprofloxacin and polyhexamethylene biguanide (PHMB) was evaluated in planktonic and biofilm growth. The effects of ciprofloxacin and PHMB on biofilms grown on porcine skin explants were evaluated by colony-forming unit (CFU) counting and confocal microscopy.
View Article and Find Full Text PDFParaquat (1,10-dimethyl-4,4-bipyridinium dichloride; PQ) is a free-radical producing herbicide that affects cell membranes and can upset the environmental balance of microorganisms present in soil, such as spp. This study aimed to evaluate the in vitro activity of PQ against spp. in planktonic and biofilm forms, as well as the protective effect of antioxidant agents against the antifungal effect of PQ and the kinetics of melanin production in response to PQ.
View Article and Find Full Text PDFStudies on the microbiota of freshwater cetaceans are scarce and may provide important data on animal and environmental health. This study aimed to evaluate the antimicrobial susceptibility of Gram-negative bacteria recovered from two populations of free-ranging Amazon river dolphins (Inia geoffrensis). Twenty-one animals were captured and released, 13 from Negro River and 8 from Tapajós River, Brazil.
View Article and Find Full Text PDFThis study aimed to evaluate the effect of aloe emodin, barbaloin and chrysophanol on growing and mature biofilms of . The compounds were added at the moment of inducing biofilm growth or after growth for 72 h to evaluate their effects on growing and mature biofilms, respectively. Then, biofilm biomass was evaluated by crystal violet staining and metabolic activity by the XTT reduction assay.
View Article and Find Full Text PDFMicrob Ecol
November 2021
This study aimed to identify Candida spp. from agricultural soils cultivated with azole fungicides and investigate their susceptibility to clinical (fluconazole, itraconazole, voriconazole, and amphotericin B) and agricultural (tetraconazole and tebuconazole) antifungals in planktonic form. Additionally, Candida biofilm-forming ability and biofilm susceptibility to agricultural antifungals and voriconazole were analyzed.
View Article and Find Full Text PDFMicrobial biofilms are a natural adaptation of microorganisms, typically composed of multiple microbial species, exhibiting complex community organization and cooperation. Biofilm dynamics and their complex architecture are challenging for basic analyses, including the number of viable cells, biomass accumulation, biofilm morphology, among others. The methods used to study biofilms range from techniques to complex models.
View Article and Find Full Text PDFThe emergence of tolerant Cryptococcus neoformans strains to antifungals has been described. It has directed researchers to screen for new antimicrobial compounds. In this context, several plant-derived compounds, such as anthraquinones (aloe emodin, barbaloin, and chrysophanol), have been investigated for their antimicrobial properties.
View Article and Find Full Text PDFThis study proposes a microcosm biofilm (MiB) model for the study of vulvovaginal candidiasis (VVC). Different conditions that mimic the vaginal environment were tested for MiB formation. The best growth conditions were obtained with samples incubated in vaginal fluid simulator medium pH 4.
View Article and Find Full Text PDFJ Med Microbiol
June 2020
species are pathogens commonly associated with cases of meningoencephalitis in individuals who are immunosuppressed due to AIDS. The aim was to evaluate the effects of the antiretroviral darunavir alone or associated with fluconazole, 5-flucytosine and amphotericin B against planktonic cells and biofilms of species. Susceptibility testing of darunavir and the common antifungals against 12 members of the / species complex was evaluated by broth microdilution.
View Article and Find Full Text PDFMicrob Pathog
June 2020
Cryptococcus neoformans/Cryptococcus gattii complex species are etiological agents of cryptococcosis, a systemic mycosis that cause respiratory infection and meningoencephalitis. To establish the infection, these yeasts produce virulence factors, such as melanin, which contribute to pathogenicity and antifungal tolerance. The aim of this study was to investigate melanin production by the C.
View Article and Find Full Text PDFMed Mycol
October 2020
This study initially aimed at investigating the occurrence of azole resistance among Candida spp. from animals and analyzing the involvement of efflux pumps in the resistance phenomenon. Then, the dynamics of antifungal resistance was assessed, by comparing the antifungal epidemiological cutoff values (ECVs) against C.
View Article and Find Full Text PDFInt J Biol Macromol
January 2020
Sporotrichosis, caused by Sporothrix schenckii complex species, is the most prevalent subcutaneous mycosis in many areas of Latin America. Chitosan has been used as an antifungal agent; however the effects of the molecular weight (MW) of chitosan (i.e.
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