Publications by authors named "Glaucia Morgana de Melo Guedes"

Article Synopsis
  • The Candida parapsilosis species complex is a significant concern in healthcare settings due to rising antifungal resistance.
  • Geraniol, a terpene from essential oils, has demonstrated potential antimicrobial effects against this yeast species in both planktonic and biofilm forms.
  • In lab tests, geraniol showed an effective minimum inhibitory concentration (MIC) between 256-512 µg/ml and reduced biofilm activity, while also enhancing the effectiveness of certain antifungal medications like amphotericin B and fluconazole.
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  • Otitis externa is a condition in dogs where the external ear canal becomes inflamed, usually due to bacterial infections, and this study focuses on testing promethazine's effectiveness against it.
  • * The research evaluated how promethazine affects bacterial growth and biofilm formation over 120 hours, determining its minimum inhibitory concentrations (MIC) and minimum biofilm eradication concentration (MBEC).
  • * Results showed that promethazine significantly reduced biofilm growth and could be a promising treatment for recurring bacterial otitis in dogs, highlighting the benefits of repurposing existing drugs to combat antimicrobial resistance.
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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.

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  • The article investigates the use of carbonyl cyanide m-chlorophenyl hydrazone (CCCP) as an efflux pump inhibitor to combat antimicrobial resistance and biofilm formation.
  • It found that CCCP significantly reduces biofilm biomass and enhances the effectiveness of antibiotics against biofilms when used at certain concentrations (128 µM and 512 µM).
  • CCCP also impacts the production of virulence factors, decreasing protease production and increasing siderophore release, indicating its potential as a therapeutic aid in managing infections related to biofilms.
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To 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.

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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 .

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This 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.

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This 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 .

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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.

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This 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.

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Freshwater 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).

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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.

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Article Synopsis
  • The report highlights a multicentric study conducted in Brazil to assess bacterial communities and antimicrobial resistance genes (ARGs) in food-producing animals and healthy humans, using rectal swabs from various regions.
  • The findings revealed a high level of microbial diversity with over 21,000 unique species identified, alongside 405 ARGs linked to multiple antibiotic classes, including previously unreported carbapenemase-encoding genes.
  • The study emphasizes the interconnectedness of humans and animals in the spread of antimicrobial resistance, particularly in low- and middle-income countries, and advocates for enhanced surveillance through One Health approaches.
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Paraquat (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.

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Studies 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.

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This 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.

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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.

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Article Synopsis
  • * This study tested how effective BRP is against four strains of C. difficile, showing a minimum inhibitory concentration of 625 μg/mL, while the control antibiotic vancomycin was more effective at 0.5-2 μg/mL.
  • * Results indicated that BRP not only inhibited the growth of C. difficile but also damaged its cell walls and significantly reduced the biomass and structure of both growing and mature biofilms.
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Microbial 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.

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The 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.

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This 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.

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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.

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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.

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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.

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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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