110 results on '"Brilhante RS"'
Search Results
2. Rhamnolipid enhances Burkholderia pseudomallei biofilm susceptibility, disassembly and production of virulence factors.
- Author
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Sidrim JJ, Ocadaque CJ, Amando BR, de M Guedes GM, Costa CL, Brilhante RS, A Cordeiro R, Rocha MF, and Scm Castelo-Branco D
- Subjects
- Bacterial Proteins genetics, Burkholderia pseudomallei genetics, Burkholderia pseudomallei growth & development, Burkholderia pseudomallei physiology, Ceftazidime pharmacology, Microbial Sensitivity Tests, Siderophores metabolism, Virulence Factors genetics, Anti-Bacterial Agents pharmacology, Bacterial Proteins metabolism, Biofilms drug effects, Burkholderia pseudomallei drug effects, Glycolipids pharmacology, Virulence Factors metabolism
- Abstract
Aim: This study evaluated the effect of the biosurfactant rhamnolipid on the antimicrobial susceptibility, biofilm growth dynamics and production of virulence factors by Burkholderia pseudomallei . Materials & methods: The effects of rhamnolipid on planktonic and biofilm growth and its interaction with antibacterial drugs were evaluated. Then, its effects on growing and mature biofilms and on protease and siderophore production were assessed. Results: Rhamnolipid did not inhibit B. pseudomallei growth, but significantly enhanced the activity of meropenem and amoxicillin-clavulanate against mature biofilms. Rhamnolipid significantly reduced the biomass of mature biofilms, significantly increased protease production by growing and mature biofilms and siderophore release by growing biofilms. Conclusion: Rhamnolipid enhances the antimicrobial activity against B. pseudomallei , assists biofilm disassembly and alters protease and siderophore production by bacterial biofilms.
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- 2020
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3. Efflux pump inhibition controls growth and enhances antifungal susceptibility of Fusarium solani species complex.
- Author
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A Cordeiro R, Portela FV, Pereira LM, de Andrade AR, de Sousa JK, Aguiar AL, Pergentino ML, de Sales GS, de Oliveira JS, Medrano DJ, Brilhante RS, Rocha MF, Scm Castelo-Branco D, and Sidrim JJ
- Subjects
- Amphotericin B pharmacology, Drug Resistance, Fungal, Drug Synergism, Humans, Membrane Transport Proteins, Microbial Sensitivity Tests, Voriconazole pharmacology, Antifungal Agents pharmacology, Biofilms drug effects, Fungal Proteins antagonists & inhibitors, Fusarium drug effects, Fusarium growth & development, Promethazine pharmacology
- Abstract
Aim: To evaluate the inhibition of efflux pumps by using promethazine (PMZ) as a strategy to control Fusarium solani species complex (FSSC). Materials & methods: The susceptibility of FSSC strains to PMZ and the interaction between PMZ and antifungals were evaluated. The efflux pump activity was confirmed by flow cytometry with rhodamine 6G. Finally, PMZ was tested against FSSC biofilms. Results: PMZ inhibited FSSC planktonic growth and showed synergism with antifungals. PMZ reduced R6G efflux and inhibited cell adhesion, impaired the development of biofilms and disrupted mature biofilms. PMZ-challenged biofilms showed increased sensitivity to amphotericin B. Conclusion: The study provides indirect evidence of the occurrence of efflux pumps in FSSC and opens a perspective for this target in the control of fusariosis.
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- 2020
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4. Terpinen-4-ol inhibits the growth of Sporothrix schenckii complex and exhibits synergism with antifungal agents.
- Author
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Brilhante RS, Pereira VS, Oliveira JS, Rodrigues AM, de Camargo ZP, Pereira-Neto WA, Nascimento NR, Castelo-Branco DS, Cordeiro RA, Sidrim JJ, and Rocha MF
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- Drug Synergism, Ergosterol analysis, Microbial Sensitivity Tests, Antifungal Agents pharmacology, Biofilms drug effects, Sporothrix drug effects, Sporothrix growth & development, Terpenes pharmacology
- Abstract
Aim: This study investigated the effect of terpinen-4-ol against Sporothrix schenckii complex and its interactions with antifungals. Materials & methods: The antifungal activity of terpinen-4-ol was evaluated by broth microdilution. The potential effect on cellular ergosterol concentration was evaluated by spectrophotometry. The antibiofilm activity was evaluated by violet crystal staining and XTT reduction assay. The potential pharmacological interactions with antifungals were evaluated by the checkerboard assay. Results: terpinen-4-ol (T-OH) showed minimal inhibitory concentrations ranging from 4 to 32 mg/l decreasing cellular ergosterol content and presented a SMIC ranging from 64 to 1024 mg/l for Sporothrix spp. The combinations of T-OH with itraconazole or terbinafine were synergistic. Conclusion: T-OH has antifungal activity against Sporothrix spp. and acts synergistically with standard antifungals.
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- 2019
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5. Chlorpromazine-impregnated catheters as a potential strategy to control biofilm-associated urinary tract infections.
- Author
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Sidrim JJ, Amando BR, Gomes FI, do Amaral MS, de Sousa PC, Ocadaque CJ, Brilhante RS, A Cordeiro R, Rocha MF, and Scm Castelo-Branco D
- Subjects
- Biofilms growth & development, Escherichia coli drug effects, Escherichia coli growth & development, Humans, Klebsiella pneumoniae drug effects, Klebsiella pneumoniae growth & development, Microbial Sensitivity Tests, Proteus mirabilis drug effects, Proteus mirabilis growth & development, Anti-Infective Agents administration & dosage, Biofilms drug effects, Catheter-Related Infections prevention & control, Chlorpromazine administration & dosage, Enterobacteriaceae Infections prevention & control, Urinary Catheterization methods, Urinary Tract Infections prevention & control
- Abstract
Aim: This study proposes the impregnation of Foley catheters with chlorpromazine (CPZ) to control biofilm formation by Escherichia coli , Proteus mirabilis and Klebsiella pneumoniae . Materials & methods: The minimum inhibitory concentrations (MICs) for CPZ and the effect of CPZ on biofilm formation were assessed. Afterward, biofilm formation and the effect of ciprofloxacin and meropenem (at MIC) on mature biofilms grown on CPZ-impregnated catheters were evaluated. Results: CPZ MIC range was 39.06-625 mg/l. CPZ significantly reduced (p < 0.05) biofilm formation in vitro and on impregnated catheters. In addition, CPZ-impregnation potentiated the antibiofilm activity of ciprofloxacin and meropenem. Conclusion: These findings bring perspectives for the use of CPZ as an adjuvant for preventing and treating catheter-associated urinary tract infections.
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- 2019
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6. Proton pump inhibitors versus Cryptococcus species: effects on in vitro susceptibility and melanin production.
- Author
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Brilhante RS, da Rocha MG, de Oliveira JS, España JD, Pereira VS, Scm Castelo-Branco D, A Pereira-Neto W, Sidrim JJ, A Cordeiro R, and Rocha MF
- Subjects
- Adenosine Triphosphatases, Copper, Copper Sulfate metabolism, Cryptococcus growth & development, Culture Media chemistry, Esomeprazole pharmacology, Glutathione metabolism, Glycine analogs & derivatives, Humans, Lansoprazole pharmacology, Microbial Sensitivity Tests, Omeprazole pharmacology, Pantoprazole pharmacology, Rabeprazole pharmacology, Glyphosate, Antifungal Agents pharmacology, Cryptococcus drug effects, Cryptococcus metabolism, Melanins biosynthesis, Proton Pump Inhibitors pharmacology
- Abstract
Aim: This study aimed to evaluate the effects of proton pump inhibitors (PPIs) on growth and melanin production by Cryptococcus spp. Materials & methods: Minimum inhibitory concentrations (MICs) of omeprazole, esomeprazole, rabeprazole, pantoprazole and lansoprazole against Cryptococcus spp. were determined and the effect of PPIs on melanin production was evaluated, in the presence or absence of copper sulfate or glutathione. Results: PPIs showed MICs ranging from 125-1000 μg/ml and decreased melanization by Cryptococcus cells. Addition of copper sulfate or gluthatione restored melanogenesis of cells grown in the presence of PPIs. The presence of PPIs and glyphosate decreased copper sulfate toxicity (1 mM). Conclusion: PPIs inhibited melanogenesis of Cryptococcus spp., possibly by chelating copper or inhibiting copper ATPase transport.
- Published
- 2019
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7. Pentamidine inhibits the growth of Sporothrix schenckii complex and exhibits synergism with antifungal agents.
- Author
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Brilhante RS, Pereira VS, Oliveira JS, Lopes RG, Rodrigues AM, Camargo ZP, Pereira-Neto WA, Castelo-Branco DS, Cordeiro RA, Sidrim JJ, and Rocha MF
- Subjects
- Biofilms drug effects, Biofilms growth & development, Drug Synergism, Microbial Sensitivity Tests, Microbial Viability drug effects, Sporothrix classification, Sporothrix physiology, Antifungal Agents pharmacology, Pentamidine pharmacology, Sporothrix drug effects
- Abstract
Aim: The purpose of this study was to evaluate the effects of the antileishmanials meglumine antimoniate and pentamidine against Sporothrix schenckii complex., Materials & Methods: The antifungal activity of the two antileishmanials was assessed by broth microdilution. The interaction between the antileishmanials and antifungal drugs (amphotericin B, itraconazole and terbinafine) was evaluated by the checkerboard assay. The effect of prior exposure of Sporothrix spp. yeast cells to antileishmanials was evaluated by broth microdilution., Results: Only pentamidine showed antifungal activity against Sporothrix spp. Synergistic interactions were observed between pentamidine and the antifungals. Also, the pre-exposure to meglumine antimoniate reduced the susceptibility of Sardinella brasiliensis and S. schenckii sensu stricto to amphotericin B and itraconazole., Conclusion: Pentamidine showed antifungal activity against Sporothrix spp., indicating it is a possible therapeutic alternative for the treatment of sporotrichosis.
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- 2018
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8. β-lactam antibiotics & vancomycin increase the growth & virulence of Candida spp.
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Aguiar Cordeiro R, de Jesus Evangelista AJ, Serpa R, Colares de Andrade AR, Leite Mendes PB, Silva Franco JD, de Oliveira JS, de Alencar LP, Sales JA, Carneiro Câmara LM, Souza Collares Maia Castelo-Branco D, Nogueira Brilhante RS, Costa Sidrim JJ, and Gadelha Rocha MF
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- Animals, Caenorhabditis elegans, Candida genetics, Candida growth & development, Humans, Microbial Sensitivity Tests, Virulence drug effects, Antifungal Agents pharmacology, Candida drug effects, Candida pathogenicity, Candidiasis microbiology, Vancomycin pharmacology, beta-Lactams pharmacology
- Abstract
Aim: To investigate the direct effect of antibiotics on growth and virulence of the major Candida species associated with invasive infections., Materials & Methods: Cefepime, imipenem, meropenem, amoxicillin and vancomycin were tested at twofold the peak plasma concentration (2× PP) and the peak plasma concentration (PP). The effects of antibiotics on Candida albicans, Candida parapsilosis, Candida krusei and Candida tropicalis were investigated by colony counting, flow cytometry, proteolytic activity and virulence in Caenorhabditis elegans., Results: Antibiotics increase growth and proteolytic activity of Candida spp; In addition, amoxicillin potentiates virulence of C. krusei and C. tropicalis against Caenorhabditis elegans., Conclusion: These results suggest that antimicrobial therapy may have a direct effect on the pathophysiology of invasive fungal infections in patients at risk.
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- 2018
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9. Aeromonas and Plesiomonas species from scarlet ibis (Eudocimus ruber) and their environment: monitoring antimicrobial susceptibility and virulence.
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Castelo-Branco DS, Silva AL, Monteiro FO, Guedes GM, Sales JA, Oliveira JS, Maia Junior JE, Miranda SA, Sidrim JJ, Alencar LP, Brilhante RS, Cordeiro RA, Bandeira TJ, Pereira Neto WA, and Rocha MF
- Subjects
- Aeromonas classification, Aeromonas drug effects, Aeromonas pathogenicity, Animals, Anti-Bacterial Agents pharmacology, Bacterial Proteins genetics, Bacterial Proteins metabolism, Ecosystem, Gram-Negative Bacterial Infections microbiology, Plesiomonas classification, Plesiomonas drug effects, Plesiomonas pathogenicity, Virulence, Aeromonas isolation & purification, Bird Diseases microbiology, Birds microbiology, Gram-Negative Bacterial Infections veterinary, Plesiomonas isolation & purification
- Abstract
The present study aimed at evaluating the role of captive scarlet ibises (Eudocimus ruber) and their environment as reservoirs of Aeromonas spp. and Plesiomonas spp., and analyzing the in vitro antimicrobial susceptibility and virulence of the recovered bacterial isolates. Thus, non-lactose and weak-lactose fermenting, oxidase positive Gram-negative bacilli were recovered from cloacal samples (n = 30) of scarlet ibises kept in a conservational facility and from water samples (n = 30) from their environment. Then, the antimicrobial susceptibility, hemolytic activity and biofilm production of the recovered Aeromonas spp. and Plesiomonas shigelloides strains were assessed. In addition, the virulence-associated genes of Aeromonas spp. were detected. Ten Aeromonas veronii bv. sobria, 2 Aeromonas hydrophila complex and 10 P. shigelloides were recovered. Intermediate susceptibility to piperacillin-tazobactam and cefepime was observed in 2 Aeromonas spp. and 1 P. shigelloides, respectively, and resistance to gentamicin was observed in 4 P. shigelloides. The automated susceptibility analysis revealed resistance to piperacillin-tazobactam and meropenem among Aeromonas spp. and intermediate susceptibility to gentamicin among P. shigelloides. All Aeromonas isolates presented hemolytic activity, while 3 P. shigelloides were non-hemolytic. All Aeromonas spp. and 3/10 P. shigelloides were biofilm-producers, at 28 °C, while 10 Aeromonas spp. and 6/10 P. shigelloides produced biofilms, at 37 °C. The most prevalent virulence genes of Aeromonas spp. were asa1 and ascV. Scarlet ibises and their environment harbour potentially pathogenic bacteria, thus requiring monitoring and measures to prevent contamination of humans and other animals.
- Published
- 2017
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10. Promethazine improves antibiotic efficacy and disrupts biofilms of Burkholderia pseudomallei.
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Sidrim JJ, Vasconcelos DC, Riello GB, Guedes GM, Serpa R, Bandeira TJ, Monteiro AJ, Cordeiro RA, Castelo-Branco DS, Rocha MF, and Brilhante RS
- Subjects
- Burkholderia pseudomallei physiology, Drug Synergism, Microbial Sensitivity Tests, Plankton drug effects, Anti-Bacterial Agents pharmacology, Biofilms drug effects, Burkholderia pseudomallei drug effects, Promethazine pharmacology
- Abstract
Efflux pumps are important defense mechanisms against antimicrobial drugs and maintenance of Burkholderia pseudomallei biofilms. This study evaluated the effect of the efflux pump inhibitor promethazine on the structure and antimicrobial susceptibility of B. pseudomallei biofilms. Susceptibility of planktonic cells and biofilms to promethazine alone and combined with antimicrobials was assessed by the broth microdilution test and biofilm metabolic activity was determined with resazurin. The effect of promethazine on 48 h-grown biofilms was also evaluated through confocal and electronic microscopy. The minimum inhibitory concentration (MIC) of promethazine was 780 mg l
-1 , while the minimum biofilm elimination concentration (MBEC) was 780-3,120 mg l-1 . Promethazine reduced the MIC values for erythromycin, trimethoprim/sulfamethoxazole, gentamicin and ciprofloxacin and reduced the MBEC values for all tested drugs (p<0.05). Microscopic analyses demonstrated that promethazine altered the biofilm structure of B. pseudomallei, even at subinhibitory concentrations, possibly facilitating antibiotic penetration. Promethazine improves antibiotics efficacy against B. pseudomallei biofilms, by disrupting biofilm structure.- Published
- 2017
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11. RYP1 gene as a target for molecular diagnosis of histoplasmosis.
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Brilhante RS, Guedes GM, Riello GB, Ribeiro JF, Alencar LP, Bandeira SP, Castelo-Branco DS, Oliveira JS, Freire JM, Mesquita JR, Camargo ZP, Cordeiro RA, Rocha MF, and Sidrim JJ
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- Acquired Immunodeficiency Syndrome complications, Base Sequence, Brazil, Coinfection diagnosis, DNA, Fungal blood, DNA, Fungal isolation & purification, Histoplasma isolation & purification, Histoplasmosis microbiology, Humans, Sensitivity and Specificity, DNA, Fungal genetics, Gene Targeting methods, Histoplasma genetics, Histoplasmosis diagnosis, Molecular Diagnostic Techniques methods
- Abstract
This study analyzed the RYP1 gene as a target for the molecular diagnosis of histoplasmosis. This assay detected fungal DNA in 13/13 blood samples from HIV/AIDS-patients with histoplasmosis. Therefore, the detection of RYP1 gene in whole blood sample is a quick and sensitive test to diagnose histoplasmosis., (Copyright © 2016 Elsevier B.V. All rights reserved.)
- Published
- 2016
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12. Terpinen-4-ol, tyrosol, and β-lapachone as potential antifungals against dimorphic fungi.
- Author
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Brilhante RS, Caetano ÉP, Lima RA, Marques FJ, Castelo-Branco DS, Melo CV, Guedes GM, Oliveira JS, Camargo ZP, Moreira JL, Monteiro AJ, Bandeira TJ, Cordeiro RA, Rocha MF, and Sidrim JJ
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- Cell Membrane Permeability drug effects, Ergosterol metabolism, Fungi classification, Fungi metabolism, Microbial Sensitivity Tests, Osmotic Pressure, Phenylethyl Alcohol pharmacology, Antifungal Agents pharmacology, Fungi drug effects, Naphthoquinones pharmacology, Phenylethyl Alcohol analogs & derivatives, Terpenes pharmacology
- Abstract
This study aimed to evaluate the in vitro antifungal activity of terpinen-4-ol, tyrosol, and β-lapachone against strains of Coccidioides posadasii in filamentous phase (n=22) and Histoplasma capsulatum in both filamentous (n=40) and yeast phases (n=13), using the broth dilution methods as described by the Clinical and Laboratory Standards Institute, to determine the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of these compounds. The mechanisms of action of these compounds were also investigated by analyzing their effect on cell membrane permeability and ergosterol synthesis. The MIC and MFCf these compounds against C. posadasii, mycelial H. capsulatum, and yeast-like H. capsulatum, were in the following ranges: 350-5720μg/mL, 20-2860μg/mL, and 40-1420μg/mL, respectively for terpinen-4-ol; 250-4000μg/mL, 30-2000μg/mL, and 10-1000μg/mL, respectively, for tyrosol; and 0.48-7.8μg/mL, 0.25-16μg/mL, and 0.125-4μg/mL, respectively for β-lapachone. These compounds showed a decrease in MIC when the samples were subjected to osmotic stress, suggesting that the compounds acted on the fungal membrane. All the compounds were able to reduce the ergosterol content of the fungal strains. Finally, tyrosol was able to cause a leakage of intracellular molecules., (Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.)
- Published
- 2016
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13. The Importance of Wild Canids in the Epidemiology of Rabies in Northeast Brazil: A Retrospective Study.
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Cordeiro Rde A, Duarte NF, Rolim BN, Soares Júnior FA, Franco IC, Ferrer LL, Almeida CP, Duarte BH, de Araújo DB, Rocha MF, Brilhante RS, Favoretto SR, and Sidrim JJ
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- Aging, Animals, Animals, Wild, Disease Reservoirs veterinary, Female, Male, Rabies epidemiology, Rabies virology, Rabies Vaccines immunology, Rabies virus, Retrospective Studies, Zoonoses, Canidae, Rabies veterinary
- Abstract
Rabies is an endemic disease in Brazil, where it is considered a serious public health problem. Although the number of human and dog-transmitted cases has declined in recent decades, rabies in wildlife has emerged considerably. Among the sylvatic animals, wild canids have been considered important hosts of the rabies virus. We performed a retrospective study of reported cases of rabies in wild canids and human victims in Ceará state (Northeast Brazil) during 2003 to 2013. Information was provided by governmental laboratories involved in rabies detection and by the Ministry of Health. From January 2003 to December 2013, a total of 11 931 animal samples were examined for rabies. Positivity were detected in 438 samples (3.67%), of which 229 (52.28%) were domestic animals, 105 (23.97%) wild canids and 104 (23.74%) other wild animals (bats, marmosets and raccoons). Approximately 33% of wild canids surveyed (n = 317) were positive for rabies. During the studied period, a total of 1923 attacks on humans by wild canids were registered. Males (n = 1405) were more affected than females (n = 520; 72.98% versus 27.01%), and the median age of all cases was 36.5 years. Injuries to individuals up to 19 years old corresponded to approximately 30% (n = 565) of all cases. Most of the victims lived in rural areas (72.46%; n = 1395), and the majority showed bites (81.13%; n = 1677) or scratches (12.23%; n = 253). Injuries were considered profound (52.1%; n = 1003), superficial (40.91; n = 788) or multiple with severe laceration (6.98%; n = 134). Only 1300 (67.53%) victims were enrolled for the complete rabies post-exposure prophylaxis scheme. Data from the present study confirm that wild canids are important hosts of rabies virus in northeastern Brazil and jeopardize rabies control in this area. Local authorities should focus their efforts in education of health professionals. In addition, strategies should be formulated to preserve wildlife., (© 2016 Blackwell Verlag GmbH.)
- Published
- 2016
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14. Synthesis and in vitro antifungal activity of isoniazid-derived hydrazones against Coccidioides posadasii.
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Cordeiro Rde A, de Melo CV, Marques FJ, Serpa R, Evangelista AJ, Caetano EP, Mafezoli J, de Oliveira Mda C, da Silva MR, Bandeira Tde J, Moreira JL, Brilhante RS, Rocha MF, and Sidrim JJ
- Subjects
- Amphotericin B pharmacology, Biosynthetic Pathways drug effects, Cell Membrane drug effects, Drug Synergism, Ergosterol biosynthesis, Itraconazole pharmacology, Microbial Sensitivity Tests, Models, Molecular, Molecular Structure, Permeability drug effects, Antifungal Agents chemical synthesis, Antifungal Agents pharmacology, Coccidioides drug effects, Hydrazones chemical synthesis, Hydrazones pharmacology
- Abstract
Coccidioidomycosis is a potentially severe infection caused by dimorphic fungi Coccidioides immitis and Coccidioides posadasii. Although guidelines are well established, refractory disease is a matter of concern in the clinical management of coccidioidomycosis. In the present study three isoniazid-derived hydrazones N'-[(E)-1-(4-methoxyphenyl)ethylidene]pyridine-4-carbohydrazide, N'-[(E)-1-(4-methylphenyl)ethylidene]pyridine-4-carbohydrazide, and N'-[(E)-1-(phenyl)ethylidene]pyridine-4-carbohydrazide were synthesized and evaluated for antifungal activity against C. posadasii. Susceptibility assays were performed by macrodilution testing. Interactions between the hydrazones and amphotericin B or itraconazole were evaluated by the checkerboard method. We also investigated the impairment of such compounds on cell ergosterol and membrane integrity. The synthesized molecules were able to inhibit C. posadasii in vitro with MIC values that ranged from 25 to 400 μg/mL. Drug interactions between synthesized molecules and amphotericin B proved synergistic for the majority of tested isolates; regarding itraconazole, synergism was observed only when strains were tested against N'-[(E)-1-(phenyl)ethylidene]pyridine-4-carbohydrazide. Reduction of cellular ergosterol was observed when strains were challenged with the hydrazones alone or combined with antifungals. Only N'-[(E)-1-(4-methylphenyl)ethylidene]pyridine-4-carbohydrazide altered membrane permeability of C. posadasii cells. Isoniazid-derived hydrazones were able to inhibit C. posadasii cells causing reduction of ergosterol content and alterations in the permeability of cell membrane. This study confirms the antifungal potential of hydrazones against pathogenic fungi., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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15. Antifungal Resistance and Virulence Among Candida spp. from Captive Amazonian manatees and West Indian Manatees: Potential Impacts on Animal and Environmental Health.
- Author
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Sidrim JJ, Carvalho VL, de Souza Collares Maia Castelo-Branco D, Brilhante RS, de Melo Guedes GM, Barbosa GR, Lazzarini SM, Oliveira DC, de Meirelles AC, Attademo FL, da Bôaviagem Freire AC, de Aquino Pereira-Neto W, de Aguiar Cordeiro R, Moreira JL, and Rocha MF
- Subjects
- Animals, Brazil, Environmental Health, Microbial Sensitivity Tests, Virulence, Candida pathogenicity, Trichechus manatus parasitology
- Abstract
This work aimed at evaluating the antifungal susceptibility and production of virulence factors by Candida spp. isolated from sirenians in Brazil. The isolates (n = 105) were recovered from the natural cavities of Amazonian and West Indian manatees and were tested for the susceptibility to amphotericin B, itraconazole, and fluconazole and for the production of phospholipases, proteases, and biofilm. The minimum inhibitory concentrations (MICs) for amphotericin B ranged from 0.03 to 1 µg/mL, and no resistant isolates were detected. Itraconazole and fluconazole MICs ranged from 0.03 to 16 µg/mL and from 0.125 to 64 µg/mL, respectively, and 35.2% (37/105) of the isolates were resistant to at least one of these azole drugs. Concerning the production of virulence factors, phospholipase activity was observed in 67.6% (71/105) of the isolates, while protease activity and biofilm production were detected in 50.5% (53/105) and 32.4% (34/105) of the isolates, respectively. Since the natural cavities of manatees are colonized by resistant and virulent strains of Candida spp., these animals can act as sources of resistance and virulence genes for the environment, conspecifics and other animal species, demonstrating the potential environmental impacts associated with their release back into their natural habitat.
- Published
- 2016
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16. Cross-resistance to fluconazole induced by exposure to the agricultural azole tetraconazole: an environmental resistance school?
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Rocha MF, Alencar LP, Paiva MA, Melo LM, Bandeira SP, Ponte YB, Sales JA, Guedes GM, Castelo-Branco DS, Bandeira TJ, Cordeiro RA, Pereira-Neto WA, Brandine GS, Moreira JL, Sidrim JJ, and Brilhante RS
- Subjects
- ATP-Binding Cassette Transporters antagonists & inhibitors, ATP-Binding Cassette Transporters genetics, ATP-Binding Cassette Transporters metabolism, Animals, Anti-Allergic Agents pharmacology, Candida genetics, Drug Resistance, Microbial, Ergosterol analysis, Gene Expression Regulation, Fungal, Humans, Itraconazole pharmacology, Malathion pharmacology, Microbial Sensitivity Tests, Promethazine pharmacology, Rhodamines, Sterol 14-Demethylase genetics, Voriconazole pharmacology, Antifungal Agents pharmacology, Candida drug effects, Chlorobenzenes pharmacology, Fluconazole pharmacology, Fungicides, Industrial pharmacology, Triazoles pharmacology
- Abstract
This study aimed to investigate the influence of tetraconazole and malathion, both used in agricultural activities, on resistance to fluconazole, itraconazole and voriconazole in Candida parapsilosis ATCC 22019. The susceptibility to tetraconazole, malathion, fluconazole, itraconazole and voriconazole, through broth microdilution. Then, 12 independent replicates, were separated and exposed to four treatment groups, each one containing three replicates: G1: tetraconazole; G2: malathion; G3: fluconazole (positive control); G4: negative control. Replicates from G1, G2 and G3, were exposed to weekly increasing concentrations of tetraconazole, malathion and fluconazole, respectively, ranging from MIC/2 to 32 × MIC, throughout 7 weeks. The exposure to tetraconazole, but not malathion, decreased susceptibility to clinical azoles, especially fluconazole. The tetraconazole-induced fluconazole resistance is partially mediated by the increased activity of ATP-dependent efflux pumps, considering the increase in antifungal susceptibility after the addition of the efflux pump inhibitor, promethazine, and the increase in rhodamine 6G efflux and CDR gene expression in the G1 replicates. Moreover, MDR expression was only detected in G1 and G3 replicates, suggesting that MDR pumps are also involved in tetraconazole-induced fluconazole resistance. It is noteworthy that tetraconazole and fluconazole-treated replicates behaved similarly, therefore, resistance to azoles of clinical use may be a consequence of using azoles in farming activities., (© 2016 Blackwell Verlag GmbH.)
- Published
- 2016
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17. In vitro susceptibility of antifungal drugs against Sporothrix brasiliensis recovered from cats with sporotrichosis in Brazil.
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Brilhante RS, Rodrigues AM, Sidrim JJ, Rocha MF, Pereira SA, Gremião ID, Schubach TM, and de Camargo ZP
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- Animals, Brazil epidemiology, Cat Diseases epidemiology, Cats, Microbial Sensitivity Tests, Sporotrichosis epidemiology, Sporotrichosis microbiology, Antifungal Agents pharmacology, Cat Diseases microbiology, Sporothrix drug effects, Sporothrix isolation & purification, Sporotrichosis veterinary
- Abstract
Sporotrichosis is an important subcutaneous mycosis of humans and animals. Classically, the disease is acquired upon traumatic inoculation of Sporothrix propagules from contaminated soil and plant debris. In addition, the direct horizontal transmission of Sporothrix among animals and the resulting zoonotic infection in humans highlight an alternative and efficient rout of transmission through biting and scratching. Sporothrix brasiliensis is the most virulent species of the Sporothrix schenckii complex and is responsible for the long-lasting outbreak of feline sporotrichosis in Brazil. However, antifungal susceptibility data of animal-borne isolates is scarce. Therefore, this study evaluated the in vitro activity of amphotericin B, caspofungin, itraconazole, voriconazole, fluconazole, and ketoconazole against animal-borne isolates of S. brasiliensis. The susceptibility tests were performed through broth microdilution (M38-A2). The results show the relevant activity of itraconazole, amphotericin B, and ketoconazole against S. brasiliensis, with the following MIC ranges: 0.125-2, 0.125-4 and 0.0312-2 μg/ml, respectively. Caspofungin was moderately effective, displaying higher variation in MIC values (0.25-64 μg/ml). Voriconazole (2-64 μg/ml) and fluconazole (62.5-500 μg/ml) showed low activity against S. brasiliensis strains. This study contributed to the characterization of the in vitro antifungal susceptibility of strains of S. brasiliensis recovered from cats with sporotrichosis, which have recently been considered the main source of human infections., (© The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2016
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18. Farnesol increases the susceptibility of Burkholderia pseudomallei biofilm to antimicrobials used to treat melioidosis.
- Author
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Castelo-Branco DS, Riello GB, Vasconcelos DC, Guedes GM, Serpa R, Bandeira TJ, Monteiro AJ, Cordeiro RA, Rocha MF, Sidrim JJ, and Brilhante RS
- Subjects
- Amoxicillin pharmacology, Anti-Bacterial Agents pharmacology, Burkholderia pseudomallei physiology, Ceftazidime pharmacology, Humans, Melioidosis drug therapy, Microbial Sensitivity Tests methods, Trimethoprim, Sulfamethoxazole Drug Combination, Biofilms drug effects, Burkholderia pseudomallei drug effects, Farnesol pharmacology, Melioidosis microbiology
- Abstract
Aims: The aim of this study was to analyse the in vitro activity of farnesol alone and combined with the antibacterial drugs amoxicillin, doxycycline, ceftazidime and sulfamethoxazole-trimethoprim against Burkholderia pseudomallei biofilms., Methods and Results: Susceptibility was assessed by the broth microdilution test and cell viability was read with the oxidation-reduction indicator dye resazurin. The biofilms were evaluated through three microscopic techniques (optical, confocal and electronic microscopy). The minimum biofilm erradication concentration (MBEC) for farnesol was 75-2400 mmol l(-1). In addition, farnesol significantly reduced the MBEC values for ceftazidime, amoxicillin, doxycycline and sulfamethoxazole-trimethoprim by 256, 16, 4 and 4 times respectively (P < 0·05). Optical, confocal and electronic microscopic analyses of farnesol-treated B. pseudomallei biofilms demonstrated that this compound damages biofilm matrix, probably facilitating antimicrobial penetration in the biofilm structure., Conclusions: This study demonstrated the effectiveness of farnesol against B. pseudomallei biofilms and its potentiating effect on the activity of antibacterial drugs, in particular ceftazidime, amoxicillin, doxycycline and sulfamethoxazole-trimethoprim., Significance and Impact of the Study: The intrinsic antimicrobial resistance of B. pseudomallei is a serious challenge for the treatment of melioidosis. Thus, this paper reports the inhibitory potential of farnesol against B. pseudomallei biofilms, as well as highlights the favourable pharmacological interaction of farnesol with antibiotics tested, not only on cell viability, but also in the structural morphology of biofilms., (© 2015 The Society for Applied Microbiology.)
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- 2016
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19. Antiretroviral drugs saquinavir and ritonavir reduce inhibitory concentration values of itraconazole against Histoplasma capsulatum strains in vitro.
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Brilhante RS, Caetano ÉP, Riello GB, Guedes GM, Castelo-Branco Dde S, Fechine MA, Oliveira JS, Camargo ZP, Mesquita JR, Monteiro AJ, Cordeiro Rde A, Rocha MF, and Sidrim JJ
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- Drug Synergism, Microbial Sensitivity Tests, Antifungal Agents pharmacology, HIV Protease Inhibitors pharmacology, Histoplasma drug effects, Itraconazole pharmacology, Ritonavir pharmacology, Saquinavir pharmacology
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Recent studies have shown that some drugs that are not routinely used to treat fungal infections have antifungal activity, such as protease inhibitor antiretroviral drugs. This study investigated the in vitro susceptibility of Histoplasma capsulatum var. capsulatum to saquinavir and ritonavir, and its combination with the antifungal itraconazole. The susceptibility assay was performed according to Clinical and Laboratory Standards Institute guidelines. All strains were inhibited by the protease inhibitor antiretroviral drugs. Saquinavir showed minimum inhibitory concentrations ranging from 0.125 to 1μgmL(-1) for both phases, and ritonavir presented minimum inhibitory concentrations ranging from 0.0312 to 4μgmL(-1)and from 0.0625 to 1μgmL(-1) for filamentous and yeast phase, respectively. Concerning the antifungal itraconazole, the minimum inhibitory concentration values ranged from 0.0019 to 0.125μgmL(-1) and from 0.0039 to 0.0312μgmL(-1) for the filamentous and yeast phase, respectively. The combination of saquinavir or ritonavir with itraconazole was synergistic against H. capsulatum, with a significant reduction in the minimum inhibitory concentrations of both drugs against the strains (p<0.05). These data show an important in vitro synergy between protease inhibitors and itraconazole against the fungus H. capsulatum., (Copyright © 2016. Published by Elsevier Editora Ltda.)
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- 2016
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20. Trends in antifungal susceptibility and virulence of Candida spp. from the nasolacrimal duct of horses.
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Brilhante RS, Bittencourt PV, Castelo-Branco Dde S, de Oliveira JS, Alencar LP, Cordeiro Rde A, Pinheiro M, Nogueira-Filho EF, Pereira-Neto Wde A, Sidrim JJ, and Rocha MF
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- Animals, Brazil, Candida classification, Candida genetics, Candida isolation & purification, Candidiasis microbiology, Cross-Sectional Studies, Female, Horses, Male, Peptide Hydrolases analysis, Phospholipases analysis, Urethra microbiology, Antifungal Agents pharmacology, Candida drug effects, Candidiasis veterinary, Drug Resistance, Fungal, Horse Diseases microbiology, Nasolacrimal Duct microbiology, Virulence Factors analysis
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This was a cross-sectional study to investigate the antifungal susceptibility and production of virulence factors in strains of Candida isolated from the outlet and the lumen of the nasolacrimal duct of horses in the state of Ceará, Brazil. The samples were obtained from 103 horses. Sterile cotton swabs were used to collect the material from the outlet of the nasolacrimal duct and urethral probes, for the instillation of 2 ml of saline solution, were used to collect samples from the lumen of the nasolacrimal duct. A total of 77 Candida isolates were obtained, with C. famata, C. tropicalis, C. guilliermondii, and C. parapsilosis sensu lato as the most prevalent species. One isolate (C. glabrata) was resistant to caspofungin. One isolate was resistant only to fluconazole (C. parapsilosis sensu lato), 11 were resistant only to itraconazole (7 C. tropicalis, 2 C. guilliermondii, 1 C. famata, 1 C. parapsilosis sensu lato), while eight C. tropicalis showed resistance to both azoles. Overall, 28 isolates produced phospholipases and 12 produced proteases. These results highlight the importance of investigating the antifungal susceptibility and virulence trends of Candida spp. from the microbiota of the nasolacrimal duct of horses., (© The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2016
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21. Enterobacteria and Vibrio from Macrobrachium amazonicum prawn farming in Fortaleza, Ceará, Brazil.
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Castelo-Branco Dde S, Sales JA, Brilhante RS, Guedes GM, Ponte YB, Sampaio CM, Bandeira Tde J, Moreira JL, Alencar LP, Paiva Mde A, Cordeiro Rde A, Monteiro AJ, Pereira-Neto Wde A, Sidrim JJ, and Rocha MF
- Abstract
Objective: To investigate the isolation of enterobacteria associated with Macrobrachium amazonicum (M. amazonicum) farming and evaluate the in vitro antimicrobial susceptibility of Vibrio strains., Methods: Strains were isolated from female M. amazonicum prawns and environmental and hatchery water. Biochemical assays were used to identify bacterial genera and those belonging to the genus Vibrio were submitted to further analyses for species identification, through Vitek 2 automated system and serotyping. Susceptibility test was performed according to Clinical Laboratory Standards Institute., Results: The following genera of enterobacteria were recovered: Enterobacter (n = 11), Citrobacter (n = 10), Proteus (n = 2), Serratia (n = 2), Kluyvera (n = 2), Providencia (n = 2), Cedecea (n = 1), Escherichia (n = 1), Edwardsiella (n = 1) and Buttiauxella (n = 1). As for Vibrio, three species were identified: Vibrio cholerae non-O1/non-O139 (n = 4), Vibrio vulnificus (V. vulnificus) (n = 1) and Vibrio mimicus (n = 1). Vibrio spp. showed minimum inhibitory concentrations values within the susceptibility range established by Clinical Laboratory Standards Institute for almost all antibiotics, except for V. vulnificus, which presented intermediate profile to ampicillin., Conclusions: Enterobacteria do not seem to be the most important pathogens associated with M. amazonicum farming, whereas the recovery of Vibrio spp. from larviculture, with emphasis on Vibrio cholerae and V. vulnificus, deserves special attention due to their role as potentially zoonotic aquaculture-associated pathogens. Furthermore, the intermediate susceptibility of V. vulnificus to ampicillin reflects the importance of monitoring drug use in prawn farming., (Copyright © 2016 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.)
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- 2016
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22. Azole resistance in Candida spp. isolated from Catú Lake, Ceará, Brazil: an efflux-pump-mediated mechanism.
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Brilhante RS, Paiva MA, Sampaio CM, Castelo-Branco DS, Teixeira CE, de Alencar LP, Bandeira TJ, Monteiro AJ, Cordeiro RA, Pereira-Neto WA, Sidrim JJ, Moreira JL, and Rocha MF
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- Biological Transport, Active, Brazil, Microbial Sensitivity Tests, Antifungal Agents metabolism, Azoles metabolism, Candida drug effects, Candida isolation & purification, Drug Resistance, Fungal, Lakes microbiology
- Abstract
Since, there is no study reporting the mechanism of azole resistance among yeasts isolated from aquatic environments; the present study aims to investigate the occurrence of antifungal resistance among yeasts isolated from an aquatic environment, and assess the efflux-pump activity of the azole-resistant strains to better understand the mechanism of resistance for this group of drugs. For this purpose, monthly water and sediment samples were collected from Catú Lake, Ceará, Brazil, from March 2011 to February 2012. The obtained yeasts were identified based on morphological and biochemical characteristics. Of the 46 isolates, 37 were Candida spp., 4 were Trichosporon asahii, 3 were Cryptococcus laurentii, 1 Rhodotorula mucilaginosa, and 1 was Kodamaea ohmeri. These isolates were subjected to broth microdilution assay with amphotericin B, itraconazole, and fluconazole, according to the methodology standardized by the Clinical and Laboratory Standards Institute (CLSI). The minimum inhibitory concentrations (MICs) of amphotericin B, itraconazole, and fluconazole were 0.03125-2μg/mL, 0.0625 to ≥16μg/mL, and 0.5 to ≥64μg/mL, respectively, and 13 resistant azole-resistant Candida isolates were detected. A reduction in the azole MICs leading to the phenotypical reversal of the azole resistance was observed upon addition of efflux-pump inhibitors. These findings suggest that the azole resistance among environmental Candida spp. is most likely associated with the overexpression of efflux-pumps., (Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.)
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- 2016
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23. Evidence of Fluconazole-Resistant Candida Species in Tortoises and Sea Turtles.
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Brilhante RS, Rodrigues PH, de Alencar LP, Riello GB, Ribeiro JF, de Oliveira JS, Castelo-Branco Dde S, Bandeira Tde J, Monteiro AJ, Rocha MF, Cordeiro Rde A, Moreira JL, and Sidrim JJ
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- Animals, Candida classification, Cloaca microbiology, Drug Resistance, Fungal, Microbial Sensitivity Tests, Mouth microbiology, Amphotericin B pharmacology, Antifungal Agents pharmacology, Candida drug effects, Candida isolation & purification, Fluconazole pharmacology, Itraconazole pharmacology, Turtles microbiology
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The aim of this study was to evaluate the antifungal susceptibility of Candida spp. recovered from tortoises (Chelonoidis spp.) and sea turtles (Chelonia mydas, Caretta caretta, Lepidochelys olivacea, Eretmochelys imbricata). For this purpose, material from the oral cavity and cloaca of 77 animals (60 tortoises and 17 sea turtles) was collected. The collected specimens were seeded on 2% Sabouraud dextrose agar with chloramphenicol, and the identification was carried out by morphological and biochemical methods. Sixty-six isolates were recovered from tortoises, out of which 27 were C. tropicalis, 27 C. famata, 7 C. albicans, 4 C. guilliermondii and 1 C. intermedia, whereas 12 strains were obtained from sea turtles, which were identified as Candida parapsilosis (n = 4), Candida guilliermondii (n = 4), Candida tropicalis (n = 2), Candida albicans (n = 1) and Candida intermedia (n = 1). The minimum inhibitory concentrations for amphotericin B, itraconazole and fluconazole ranged from 0.03125 to 0.5, 0.03125 to >16 and 0.125 to >64, respectively. Overall, 19 azole-resistant strains (14 C. tropicalis and 5 C. albicans) were found. Thus, this study shows that Testudines carry azole-resistant Candida spp.
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- 2015
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24. Inhibitory activity of isoniazid and ethionamide against Cryptococcus biofilms.
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Cordeiro Rde A, Serpa R, Marques FJ, de Melo CV, Evangelista AJ, Mota VF, Brilhante RS, Bandeira Tde J, Rocha MF, and Sidrim JJ
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- Antifungal Agents pharmacology, Cell Membrane Permeability, Ergosterol chemistry, Fluconazole pharmacology, Microbial Sensitivity Tests, Biofilms drug effects, Cryptococcus gattii drug effects, Cryptococcus neoformans drug effects, Ethionamide pharmacology, Isoniazid pharmacology
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In recent years, the search for drugs to treat systemic and opportunistic mycoses has attracted great interest from the scientific community. This study evaluated the in vitro inhibitory effect of the antituberculosis drugs isoniazid and ethionamide alone and combined with itraconazole and fluconazole against biofilms of Cryptococcus neoformans and Cryptococcus gattii. Antimicrobials were tested at defined concentrations after susceptibility assays with Cryptococcus planktonic cells. In addition, we investigated the synergistic interaction of antituberculosis drugs and azole derivatives against Cryptococcus planktonic cells, as well as the influence of isoniazid and ethionamide on ergosterol content and cell membrane permeability. Isoniazid and ethionamide inhibited both biofilm formation and viability of mature biofilms. Combinations formed by antituberculosis drugs and azoles proved synergic against both planktonic and sessile cells, showing an ability to reduce Cryptococcus biofilms by approximately 50%. Furthermore, isoniazid and ethionamide reduced the content of ergosterol in Cryptococcus spp. planktonic cells and destabilized or permeabilized the fungal cell membrane, leading to leakage of macromolecules. Owing to the paucity of drugs able to inhibit Cryptococcus biofilms, we believe that the results presented here might be of interest in the designing of new antifungal compounds.
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- 2015
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25. In vitro antifungal activity of miltefosine and levamisole: their impact on ergosterol biosynthesis and cell permeability of dimorphic fungi.
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Brilhante RS, Caetano EP, Lima RA, Castelo Branco DS, Serpa R, Oliveira JS, Monteiro AJ, Rocha MF, Cordeiro RA, and Sidrim JJ
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- Cell Membrane Permeability drug effects, Coccidioides growth & development, Coccidioides metabolism, Histoplasma drug effects, Histoplasma metabolism, Microbial Sensitivity Tests, Phosphorylcholine pharmacology, Antifungal Agents pharmacology, Coccidioides drug effects, Ergosterol biosynthesis, Histoplasma growth & development, Levamisole pharmacology, Phosphorylcholine analogs & derivatives
- Abstract
Aims: This study aimed to evaluate the in vitro activity of miltefosine and levamisole against strains of Coccidioides posadasii in the filamentous phase and strains of Histoplasma capsulatum in filamentous and yeast phases., Methods and Results: Strains of C. posadasii in the filamentous phase (n = 22) and strains of H. capsulatum in filamentous (n = 40) and yeast phases (n = 13) were, respectively, submitted to broth macrodilution and broth microdilution methods, as described by the Clinical and Laboratory Standards Institute, to determine the minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) of miltefosine and levamisole. The effect of the drugs on cell membrane permeability under osmotic stress conditions and total ergosterol production were also assessed, along with quantification of extravasated molecules. The results show the inhibitory effect of levamisole and miltefosine against C. posadasii and H. capsulatum and the effect of these drugs on ergosterol synthesis and the permeability of the plasma membrane using subinhibitory concentrations against strains subjected to osmotic stress. Levamisole was also able to cause the release of nucleic acids., Conclusions: Miltefosine and levamisole are capable of inhibiting the in vitro growth of C. posadasii and H. capsulatum, probably by altering the permeability of the cellular membrane., Significance and Impact of the Study: This work presents alternatives for the treatment of histoplasmosis and coccidioidomycosis, raising the possibility of the use of miltefosine and levamisole as adjuvants in antifungal therapy, providing perspectives for the design of in vivo studies., (© 2015 The Society for Applied Microbiology.)
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- 2015
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26. Yeast microbiota of natural cavities of manatees (Trichechus inunguis and Trichechus manatus) in Brazil and its relevance for animal health and management in captivity.
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Sidrim JJ, Carvalho VL, Castelo-Branco Dde S, Brilhante RS, Bandeira Tde J, Cordeiro Rde A, Guedes GM, Barbosa GR, Lazzarini SM, Oliveira DC, de Meirelles AC, Attademo FL, Freire AC, Moreira JL, Monteiro AJ, and Rocha MF
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- Animals, Brazil, Candida isolation & purification, Candida physiology, Cryptococcus isolation & purification, Cryptococcus physiology, Female, Male, Rhodotorula isolation & purification, Rhodotorula physiology, Trichechus inunguis microbiology, Trichechus manatus microbiology, Trichosporon isolation & purification, Trichosporon physiology, Microbiota, Trichechus microbiology
- Abstract
The aim of this study was to characterize the yeast microbiota of natural cavities of manatees kept in captivity in Brazil. Sterile swabs from the oral cavity, nostrils, genital opening, and rectum of 50 Trichechus inunguis and 26 Trichechus manatus were collected. The samples were plated on Sabouraud agar with chloramphenicol and incubated at 25 °C for 5 days. The yeasts isolated were phenotypically identified by biochemical and micromorphological tests. Overall, 141 strains were isolated, of which 112 were from T. inunguis (Candida albicans, Candida parapsilosis sensu stricto, Candida orthopsilosis, Candida metapsilosis, Candida guilliermondii, Candida pelliculosa, Candida tropicalis, Candida glabrata, Candida famata, Candida krusei, Candida norvegensis, Candida ciferri, Trichosporon sp., Rhodotorula sp., Cryptococcus laurentii) and 29 were from T. manatus (C. albicans, C. tropicalis, C. famata, C. guilliermondii, C. krusei, Rhodotorula sp., Rhodotorula mucilaginosa, Rhodotorula minuta, Trichosporon sp.). This was the first systematic study to investigate the importance of yeasts as components of the microbiota of sirenians, demonstrating the presence of potentially pathogenic species, which highlights the importance of maintaining adequate artificial conditions for the health of captive manatees.
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- 2015
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27. Emergence of azole-resistant Candida albicans in small ruminants.
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Brilhante RS, Silva ST, Castelo-Branco DS, Teixeira CE, Borges LC, Bittencourt PV, de Oliveira JS, Monteiro AJ, Bandeira TJ, Cordeiro RA, Moreira JL, Sidrim JJ, and Rocha MF
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- Animals, Brazil, Mouth microbiology, Nasal Cavity microbiology, Rectum microbiology, Rhodotorula isolation & purification, Trichosporon isolation & purification, Antifungal Agents pharmacology, Azoles pharmacology, Candida albicans isolation & purification, Drug Resistance, Fungal, Goats microbiology, Sheep microbiology
- Abstract
Small ruminant production is a common agricultural activity worldwide. However, studies on the fungal microbiota of these animals are scarce. Therefore, this study aimed at isolating yeasts from goats and sheep and evaluating the antifungal susceptibility of the recovered Candida albicans. A total of 120 animals from farms in Ceará State, Brazil, were assessed in this study. The samples were collected from nasal, oral and rectal cavities with sterile swabs. Candida spp., Trichosporon spp. and Rhodotorula spp. were isolated from small ruminants. Resistance to three azole drugs was observed in C. albicans. In summary, Candida spp. were predominantly observed as part of the microbiota of the nasal, oral and rectal cavities of small ruminants, including azole-resistant strains of C. albicans.
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- 2015
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28. Simvastatin inhibits planktonic cells and biofilms of Candida and Cryptococcus species.
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Brilhante RS, Caetano EP, Oliveira JS, Castelo-Branco Dde S, Souza ER, Alencar LP, Cordeiro Rde A, Bandeira Tde J, Sidrim JJ, and Rocha MF
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- Amphotericin B pharmacology, Animals, Biofilms growth & development, Candida classification, Candida physiology, Cryptococcus classification, Cryptococcus physiology, Drug Synergism, Fluconazole pharmacology, Itraconazole pharmacology, Microbial Sensitivity Tests, Antifungal Agents pharmacology, Biofilms drug effects, Candida drug effects, Cryptococcus drug effects, Simvastatin pharmacology
- Abstract
The antifungal activity of some statins against different fungal species has been reported. Thus, at the first moment, the in vitro antifungal activity of simvastatin, atorvastatin and pravastatin was tested against Candida spp. and Cryptococcus spp. Then, in a second approach, considering that the best results were obtained for simvastatin, this drug was evaluated in combination with antifungal drugs against planktonic growth and tested against biofilms of Candida spp. and Cryptococcus spp. Drug susceptibility testing was performed using the microdilution broth method, as described by the Clinical and Laboratory Standards Institute. The interaction between simvastatin and antifungals against planktonic cells was analyzed by calculating the fractional inhibitory concentration index. Regarding biofilm susceptibility, simvastatin was tested against growing biofilm and mature biofilm of one strain of each tested yeast species. Simvastatin showed inhibitory effect against Candida spp. and Cryptococcus spp. with minimum inhibitory concentration values ranging from 15.6 to 1000 mg L(-1) and from 62.5 to 1000 mg L(-1), respectively. The combination of simvastatin with itraconazole and fluconazole showed synergism against Candida spp. and Cryptococcus spp., while the combination of simvastatin with amphotericin B was synergistic only against Cryptococcus spp. Concerning the biofilm assays, simvastatin was able to inhibit both growing biofilm and mature biofilm of Candida spp. and Cryptococcus spp. The present study showed that simvastatin inhibits planktonic cells and biofilms of Candida and Cryptococcus species., (Copyright © 2015 Elsevier Editora Ltda. All rights reserved.)
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- 2015
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29. Virulence and antimicrobial susceptibility of clinical and environmental strains of Aeromonas spp. from northeastern Brazil.
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Castelo-Branco Dde S, Guedes GM, Brilhante RS, Rocha MF, Sidrim JJ, Moreira JL, Cordeiro Rde A, Sales JA, Riello GB, de Alencar LP, Paiva Mde A, Vasconcelos DC, de Menezes IS, de Ponte YB, Sampaio CM, Monteiro AJ, and Bandeira Tde J
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- Aeromonas drug effects, Aeromonas genetics, Brazil, Drug Resistance, Bacterial, Humans, Microbial Sensitivity Tests, Virulence genetics, Aeromonas pathogenicity, Environmental Microbiology
- Abstract
The aims of the present study were to isolate and identify clinical and environmental strains of Aeromonas spp. by means of biochemical tests and the automated method VITEK 2 and to investigate the presence of the virulence genes cytotoxic enterotoxin (act), hemolysin (asa-1), and type III secretion system (ascV), and also the in vitro antimicrobial susceptibility of the strains. From the clinical isolates, 19 Aeromonas hydrophila, 3 Aeromonas veronii bv. sobria, and 1 Aeromonas caviae were identified, while from the environmental strains, 11 A. hydrophila, 22 A. veronii bv. sobria, 1 A. veronii bv. veronii, and 1 A. caviae were recovered. The gene act was detected in 69.5% of clinical isolates, asa-1 in 8.6%, and ascV in 34.7%. In the environmental strains, the detection rates were 51.4%, 45.7%, and 54.2% for the genes act, asa-1, and ascV, respectively. Resistance to amoxicillin-clavulanate and piperacillin-tazobactam was observed in 15 and 3 clinical strains, respectively, and resistance to ceftazidime, meropenem, imipenem, ciprofloxacin, and trimethoprim-sulfamethoxazole was observed in 1 strain for each drug. Resistance to amoxicillin-clavulanate and piperacillin-tazobactam was detected in 17 and 1 environmental strain, respectively. Higher resistance percentages were observed in clinical strains, but environmental strains also showed this phenomenon and presented a higher detection rate of virulence genes. Thus, it is important to monitor the antimicrobial susceptibility and pathogenic potential of the environmental isolates.
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- 2015
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30. Exogenous tyrosol inhibits planktonic cells and biofilms of Candida species and enhances their susceptibility to antifungals.
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Cordeiro Rde A, Teixeira CE, Brilhante RS, Castelo-Branco DS, Alencar LP, de Oliveira JS, Monteiro AJ, Bandeira TJ, Sidrim JJ, Moreira JL, and Rocha MF
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- Amphotericin B metabolism, Fluconazole metabolism, Itraconazole metabolism, Microbial Sensitivity Tests, Phenylethyl Alcohol metabolism, Antifungal Agents metabolism, Biofilms drug effects, Candida drug effects, Candida physiology, Drug Synergism, Phenylethyl Alcohol analogs & derivatives
- Abstract
Tyrosol is a quorum-sensing molecule of Candida albicans able to induce hyphal development in the early and intermediate stages of biofilm growth. In the present study, we evaluated the effect of high concentrations of exogenous tyrosol on planktonic cells and biofilms of C. albicans (n = 10) and C. tropicalis (n = 10), and investigated whether tyrosol could be synergic to antifungals that target cellular ergosterol. Antifungal susceptibility and drug interaction against planktonic cells were investigated by the broth microdilution method. Tyrosol was able to inhibit planktonic cells, with MIC values ranging from 2.5 to 5.0 mM for both species. Synergism was observed between tyrosol/amphotericin B (11/20 strains), tyrosol/itraconazole (18/20 strains) and tyrosol/fluconazole (18/20 strains). Exogenous tyrosol alone or combined with antifungals at both 10 × MIC and 50 × MIC were able to reduce biofilm of both Candida species. Mature biofilms were susceptible to tyrosol alone at 50 × MIC or combined with amphotericin at both 10 × MIC and 50 × MIC. On the other hand, tyrosol plus azoles at both 10 × MIC and 50 × MIC enhanced biofilm growth., (© FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2015
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31. β-Lactam antibiotics and vancomycin inhibit the growth of planktonic and biofilm Candida spp.: an additional benefit of antibiotic-lock therapy?
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Sidrim JJ, Teixeira CE, Cordeiro RA, Brilhante RS, Castelo-Branco DS, Bandeira SP, Alencar LP, Oliveira JS, Monteiro AJ, Moreira JL, Bandeira TJ, and Rocha MF
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- Candida growth & development, Catheter-Related Infections prevention & control, Humans, Microbial Sensitivity Tests, Microbial Viability drug effects, Anti-Bacterial Agents pharmacology, Biofilms drug effects, Biofilms growth & development, Candida drug effects, Candida physiology, Vancomycin pharmacology, beta-Lactams pharmacology
- Abstract
The aim of this study was to evaluate the effects of cefepime, meropenem, piperacillin/tazobactam (TZP) and vancomycin on strains of Candida albicans and Candida tropicalis in planktonic and biofilm forms. Twenty azole-derivative-resistant strains of C. albicans (n=10) and C. tropicalis (n=10) were tested. The susceptibility of planktonic Candida spp. to the antibacterial agents was investigated by broth microdilution. The XTT reduction assay was performed to evaluate the viability of growing and mature biofilms following exposure to these drugs. Minimum inhibitory concentrations (MICs) ranged from 0.5 mg/mL to 2 mg/mL for cefepime, TZP and vancomycin and from 0.5 mg/mL to 1 mg/mL for meropenem and the drugs also caused statistically significant reductions in biofilm cellular activity both in growing and mature biofilm. Since all of the tested drugs are commonly used in patients with hospital-acquired infections and in those with catheter-related infections under antibiotic-lock therapy, it may be possible to obtain an additional benefit from antibiotic-lock therapy with these drugs, namely the control of Candida biofilm formation., (Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.)
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- 2015
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32. Easy storage strategies for Sporothrix spp. strains.
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Brilhante RS, Silva NF, Lima RA, Caetano ÉP, Alencar LP, Castelo-Branco Dde S, Moreira JL, Bandeira SP, Camargo ZP, Rodrigues AM, Bandeira Tde J, Monteiro AJ, Cordeiro Rde A, Sidrim JJ, and Rocha MF
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- Cryopreservation, Glycerol chemistry, Lactose chemistry, Microbial Viability, Sporothrix chemistry, Sucrose chemistry, Time, Preservation, Biological methods, Sporothrix physiology
- Abstract
The present study evaluated the maintenance of Sporothrix spp. (6 Sporothrix brasiliensis; 6 S. schenckii; 5 S. mexicana, and 3 S. globosa) in saline at 4°C, and in 10% glycerol plus either 10% lactose or 10% sucrose, at -20°C and -80°C. Viability was assessed after 3, 6, and 9 months of storage, through the recovery of strains on potato dextrose agar and analysis of macro- and micromorphological features. Conidium quantification was performed before and after storage, at 3, 6 and 9 months. 100% viability was observed, regardless of storage conditions or time period. Storage at 4°C and at -20°C did not alter the number of conidia, but lower conidium counts were observed at -80°C. This study shows that the combination of glycerol with lactose or sucrose is effective to maintain Sporothrix spp. at freezing temperatures.
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- 2015
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33. Bipolaris hawaiiensis as an emerging cause of cutaneous phaeohyphomycosis in an Antillean manatee Trichechus manatus manatus.
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Costa Sidrim JJ, Carvalho VL, Branco de Souza Collares Maia DC, Nogueira Brilhante RS, de Meirelles AC, Negrão Silva CP, de Aguiar Cordeiro R, Bezerra Moreira JL, de Jesus Pinheiro Gomes Bandeira T, and Gadelha Rocha MF
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- Animals, Antifungal Agents therapeutic use, Brazil epidemiology, Communicable Diseases, Emerging drug therapy, Communicable Diseases, Emerging epidemiology, Female, Itraconazole therapeutic use, Mitosporic Fungi classification, Phaeohyphomycosis drug therapy, Phaeohyphomycosis epidemiology, Phaeohyphomycosis microbiology, Communicable Diseases, Emerging microbiology, Mitosporic Fungi isolation & purification, Phaeohyphomycosis veterinary, Trichechus manatus microbiology
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Phaeohyphomycoses are emerging and opportunistic diseases caused by dematiaceous fungi that infect many animal species. This paper describes a case of cutaneous phaeohyphomycosis in an Antillean manatee Trichechus manatus manatus caused by Bipolaris hawaiiensis. Blackish skin lesions were observed in an Antillean manatee calf held captive in Brazil. Direct examination of skin scraping from the affected areas revealed the presence of dematious hyphae. Culture of skin fragments led to the isolation and subsequent identification of B. hawaiiensis as the etiologic agent. Treatment with itraconazole for 14 d was effective. Infections by Bipolaris spp. are rare in animals, and this is the first report of B. hawaiiensis in veterinary medicine.
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- 2015
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34. In vitro inhibitory activity of terpenic derivatives against clinical and environmental strains of the Sporothrix schenkii complex.
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Brilhante RS, Silva NF, Marques FJ, Castelo-Branco Dde S, de Lima RA, Malaquias AD, Caetano EP, Barbosa GR, de Camargo ZP, Rodrigues AM, Monteiro AJ, Bandeira Tde J, Cordeiro Rde A, Sidrim JJ, Moreira JL, and Rocha MF
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- Cell Membrane drug effects, Humans, Microbial Sensitivity Tests, Microbial Viability drug effects, Permeability drug effects, Sporothrix isolation & purification, Antifungal Agents pharmacology, Environmental Microbiology, Farnesol pharmacology, Sporothrix drug effects, Sporotrichosis microbiology, Terpenes pharmacology
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Sporotrichosis is a subacute or chronic subcutaneous infection, caused by the fungus Sporothrix schenkii complex, occurring in human and animal tissues. Potassium iodide and itraconazole have been used as effective therapy for first-choice treatment, while amphotericin B may be indicated for disseminated infection. However, the adverse effects of potassium iodide and amphotericin B or the long duration of therapy with itraconazole often weigh against their use, leading to the search for alternatives for the treatment of severe infections. Terpinen-4-ol and farnesol are components of essential oils present in many plant species and have been described to have antifungal activity against microorganisms. In this study, 40 strains of Sporothrix spp. were tested for the susceptibility to terpinen-4-ol and farnesol. Changes in cytoplasmic membrane permeability were also investigated. Terpenes inhibited all Sporothrix strains with MIC values ranging from 87.9 to 1,429.8 μg/ml for terpinen-4-ol and from 0.003 to 0.222 μg/ml for farnesol. The MFC values ranged from 177.8 to 5,722.6 μg/ml and from 0.027 to 0.88 μg/ml, respectively, for terpinen-4-ol and farnesol. Farnesol was the most active compound for the Sporothrix strains. Significant loss of 260 and 280 nm-absorbing material did not occur after treatment with concentrations equivalent to the MIC and sub-MIC of the tested terpenes, when compared to corresponding untreated samples. The failure of terpenes to lyse Sporothrix cells suggests that their primary mechanism of action is not by causing irreversible cell membrane damage. Thus, new studies are needed to better understand the mechanisms involved in the antifungal activity., (© The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2015
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35. Candida tropicalis isolates obtained from veterinary sources show resistance to azoles and produce virulence factors.
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Cordeiro Rde A, de Oliveira JS, Castelo-Branco Dde S, Teixeira CE, Marques FJ, Bittencourt PV, Carvalho VL, Bandeira Tde J, Brilhante RS, Moreira JL, Pereira-Neto Wde A, Sidrim JJ, and Rocha MF
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- Animals, Animals, Domestic, Animals, Wild, Biofilms growth & development, Candida tropicalis isolation & purification, Candida tropicalis physiology, Microbial Sensitivity Tests, Antifungal Agents pharmacology, Azoles pharmacology, Candida tropicalis drug effects, Candida tropicalis enzymology, Drug Resistance, Fungal, Enzymes analysis, Virulence Factors analysis
- Abstract
Candida tropicalis has been associated with invasive candidiasis, being the first or second most common non-Candida albicans Candida species isolated in humans with candidemia and candiduria, as well as being frequently isolated from healthy animals. This study aimed to characterize C. tropicalis isolates (n = 64) obtained from several animal species regarding antifungal susceptibility and production of virulence factors. The isolates were obtained from the microbiota of healthy animals (goats, n = 25; sheep, n = 6; psittacines, n = 14; rheas, n = 6; horses, n = 2; sirenians, n = 5; shrimp, n = 1), as well as from aquatic mammals found dead in the environment (cetaceans, n = 5). The isolates were subjected to in vitro susceptibility testing by broth microdilution according to the CLSI M27-A3 protocol against amphotericin B, caspofungin, itraconazole, and fluconazole. We also evaluated the virulence attributes, such as proteases and phospholipases, as well as biofilm formation. Resistance to itraconazole (n = 29) and fluconazole (n = 30) was detected among isolates from every source; resistance to both azoles was detected in 24 isolates, but none of them were resistant to amphotericin B and caspofungin. Protease production was detected in the majority of the isolates (n = 59), but phospholipase was produced by only a few of them (n = 6). The isolates showed different patterns in biofilm production, being considered strong producers (n = 41), moderate producers (n = 11), weak producers (n = 9) or non-producers (n = 3). In summary, C. tropicalis isolated from animals showed high rate of resistance to azoles, expressed virulence factors and therefore may represent a potential threat to human and animal health., (© The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2015
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36. Synthesis and antifungal activity in vitro of isoniazid derivatives against histoplasma capsulatum var. capsulatum.
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de Aguiar Cordeiro R, de Farias Marques FJ, de Aguiar Cordeiro R, da Silva MR, Donato Maia Malaquias A, Silva de Melo CV, Mafezoli J, Ferreira de Oliveira Mda C, Nogueira Brilhante RS, Gadelha Rocha MF, Pinheiro Gomes Bandeira Tde J, and Costa Sidrim JJ
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- Microbial Sensitivity Tests, Antifungal Agents pharmacology, Histoplasma drug effects, Isoniazid pharmacology
- Abstract
Histoplasmosis is a severe infection that affects millions of patients worldwide and is endemic in the Americas. Amphotericin B (AMB) and itraconazole are highly effective for the treatment of severe and milder forms of the disease, but AMB is toxic, and the bioavailability of itraconazole is erratic. Therefore, it is important to investigate new classes of drugs for histoplasmosis treatment. In this study, a series of nine isoniazid hydrazone derivatives were synthesized and evaluated for their antifungal activities in vitro against the dimorphic fungus Histoplasma capsulatum var. capsulatum. The drugs were tested by microdilution in accordance with CLSI guidelines. The compound N'-(1-phenylethylidene)isonicotinohydrazide had the lowest MIC range of all the compounds for the yeast and filamentous forms of H. capsulatum. The in vitro synergy of this compound with AMB against the planktonic and biofilm forms of H. capsulatum cells was assessed by the checkerboard method. The effects of this hydrazone on cellular ergosterol content and membrane integrity were also investigated. The study showed that the compound alone is able to reduce the ergosterol content of planktonic cells and can alter the membrane permeability of the fungus. Furthermore, the compound alone or in combination with AMB showed inhibitory effects against mature biofilms of H. capsulatum. N'-(1-Phenylethylidene)isonicotinohydrazide alone or combined with AMB might be of interest in the management of histoplasmosis.
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- 2014
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37. In vitro inhibitory effect of miltefosine against strains of Histoplasma capsulatum var. capsulatum and Sporothrix spp.
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Brilhante RS, Malaquias AD, Caetano EP, Castelo-Branco Dde S, Lima RA, Marques FJ, Silva NF, Alencar LP, Monteiro AJ, Camargo ZP, Bandeira Tde J, Rodrigues AM, Cordeiro Rde A, Moreira JL, Sidrim JJ, and Rocha MF
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- Microbial Sensitivity Tests, Microbial Viability drug effects, Phosphorylcholine pharmacology, Antifungal Agents pharmacology, Histoplasma drug effects, Phosphorylcholine analogs & derivatives, Sporothrix drug effects
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Miltefosine (MIL), originally developed for use in cancer chemotherapy, has been shown to have important antifungal activity against several pathogenic fungi. Our aim in this study was to determine the in vitro activity of MIL against the dimorphic fungi Histoplasma capsulatum and Sporothrix spp. This was done using the broth microdilution method. MIL had an in vitro inhibitory effect against all strains of H. capsulatum var. capsulatum and Sporothrix spp. analyzed. The minimal inhibitory concentrations (MIC) varied from 0.25 μg/ml to 2 μg/ml for H. capsulatum var. capsulatum in the filamentous phase and from 0.125 μg/ml to 1 μg/ml in the yeast phase. The MIC interval for Sporothrix spp. in the filamentous phase was 0.25-2 μg/ml. The minimal fungicidal concentrations (MFCs) were ≤4 μg/ml for isolates of both analyzed species. This study demonstrates that MIL has an antifungal effect in vitro against two potentially pathogenic fungi and that more studies should be performed in order to evaluate its applicability in vivo.
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- 2014
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38. In vitro activities of amoxicillin-clavulanate, doxycycline, ceftazidime, imipenem, and trimethoprim-sulfamethoxazole against biofilm of Brazilian strains of Burkholderia pseudomallei.
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Bandeira Tde J, Moreira CA, Brilhante RS, Castelo-Branco Dde S, Neto MP, Cordeiro Rde A, Rodrigues Tde J, Rocha MF, and Sidrim JJ
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- Biofilms growth & development, Brazil, Burkholderia pseudomallei growth & development, Drug Resistance, Multiple, Bacterial, Humans, Microbial Sensitivity Tests, Plankton drug effects, Plankton growth & development, Amoxicillin-Potassium Clavulanate Combination pharmacology, Anti-Bacterial Agents pharmacology, Biofilms drug effects, Burkholderia pseudomallei drug effects, Ceftazidime pharmacology, Doxycycline pharmacology, Imipenem pharmacology, Trimethoprim, Sulfamethoxazole Drug Combination pharmacology
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This study aimed at investigating the in vitro activities of amoxicillin-clavulanate, doxycycline, ceftazidime, imipenem, and trimethoprim-sulfamethoxazole against Burkholderia pseudomallei in planktonic and biofilm forms, through broth microdilution and resazurin-based viability staining, respectively. In planktonic growth, the strains were susceptible to the drugs, while in biofilm growth, significantly higher antimicrobial concentrations were required, especially for ceftazidime and imipenem, surpassing the resistance breakpoints. These results highlight the importance of the routine evaluation of biofilm antimicrobial susceptibility.
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- 2013
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39. Trichophyton tonsurans strains from Brazil: phenotypic heterogeneity, genetic homology, and detection of virulence genes.
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Sidrim JJ, Rocha MF, Leite JJ, Maranhão FC, Lima RA, Castelo-Branco Dde S, Bandeira Tde J, Cordeiro Rde A, and Brilhante RS
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- Antifungal Agents pharmacology, Brazil epidemiology, Child, DNA Fingerprinting, Genotype, Humans, Phenotype, Polymerase Chain Reaction, Polymorphism, Restriction Fragment Length, Random Amplified Polymorphic DNA Technique, Restriction Mapping, Scalp microbiology, Tinea Capitis epidemiology, Tinea Capitis genetics, Trichophyton drug effects, Trichophyton genetics, Trichophyton pathogenicity, Virulence genetics, Tinea Capitis microbiology, Trichophyton classification, Virulence Factors genetics
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The objective of this study was to establish the phenotypical and molecular patterns of clinical isolates of Trichophyton tonsurans circulating in the state of Ceará, northeastern Brazil. For this purpose, 25 T. tonsurans strains isolated from independent cases of tinea capitis in children were phenotypically evaluated regarding their macro- and micro-morphological characteristics, vitamin requirements, urease production, and antifungal susceptibility. The molecular characterization was carried out with random amplified polymorphic DNA molecular markers and M13 fingerprinting. The presence of the genes CarbM14, Sub2, CER, URE, ASP, PBL, and LAC, which encode enzymes related to fungal virulence, was also evaluated. Finally, melanin production was assessed through specific staining. The data obtained demonstrated that these T. tonsurans strains have considerable phenotypical variation, although they showed a low degree of genetic polymorphism according to the markers used. The genes CarbM14, Sub2, CER, and URE were detected in all the analyzed strains. The gene LAC was also identified in all the strains, and melanin synthesis was phenotypically confirmed. The strains were susceptible to antifungals, especially itraconazole (GM = 0.06 μg/mL) and ketoconazole (GM = 0.24 μg/mL). Therefore, T. tonsurans strains can present great phenotypical heterogeneity, even in genetically similar isolates. Moreover, the presence of the LAC gene indicates the possible participation of melanin in the pathogenesis of these dermatophytes.
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- 2013
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40. In vitro antimicrobial susceptibility of clinical and environmental strains of Burkholderia pseudomallei from Brazil.
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Bandeira Tde J, Brilhante RS, Rocha MF, Moreira CA, Cordeiro Rde A, Ribeiro JF, Castelo-Branco Dde S, and Sidrim JJ
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- Humans, Anti-Bacterial Agents pharmacology, Burkholderia pseudomallei drug effects, Melioidosis drug therapy, Melioidosis microbiology
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- 2013
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41. Species of Candida as a component of the nasal microbiota of healthy horses.
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Cordeiro Rde A, Bittencourt PV, Brilhante RS, Teixeira CE, Castelo-Branco Dde S, Silva ST, De Alencar LP, Souza ER, Bandeira Tde J, Monteiro AJ, Sidrim JJ, and Rocha MF
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- Animals, Antifungal Agents pharmacology, Candida classification, Candida drug effects, Female, Male, Microbiological Techniques methods, Mycology methods, Candida isolation & purification, Horses microbiology, Microbiota, Nasal Mucosa microbiology
- Abstract
Respiratory infections are a common problem among equines and occur with variable rates of morbidity and mortality. Although some fungal species are considered primary agents of respiratory tract infections in several mammals, their relevance in respiratory diseases of equines is frequently neglected. In the present study, we performed an active search for Candida spp. in the nasal cavity of horses. The presence of Candida spp. was investigated through the use of nasal swabs that were streaked on culture media. These yeasts were identified through physiological testing and their in vitro antifungal susceptibility were also characterized. The analysis of the material from the nasal cavity of 97 randomly chosen horses resulted in the isolation of Candida spp. from 35 animals (36.08%), out of which 18 (32.14%) were C. famata, 14 (25%) C. parapsilosis, 12 (21.42%) Meyerozyma guilliermondii (C. guilliermondii), 11 (19.64%) C. tropicalis and 1 (1.78%) Wickerhamomyces anomalus (C. pelliculosa). The minimum inhibitory concentration (MIC) values ranged from 0.03125-1 μg/ml for amphotericin B; and from 0.03125-> 16 μg/ml and 0.125 to > 64 μg/ml for itraconazole and fluconazole, respectively. Resistance to fluconazole and itraconazole was observed among C. tropicalis (n = 3) and C. guilliermondii (n = 1). The data show a predominance of non-C. albicans Candida species in the nasal microbiota of healthy equines, including antifungal resistant isolates, reiterating the importance of monitoring fungal pathogens in these animals.
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- 2013
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42. Antifungal susceptibility of emerging opportunistic yeasts and yeast-like fungi from Rhea americana.
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de Aguiar Cordeiro R, Pereira de Alencar L, Nogueira Brilhante RS, de Souza Collares Maia Castelo-Branco D, Cordeiro Teixeira CE, de Brito Macedo R, Teixeira Lima D, Paiva de Araújo Neto M, Jalles Monteiro A, Dutra Alves N, Franco de Oliveira M, Costa Sidrim JJ, and Rocha Gadelha MF
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- Animals, Drug Resistance, Fungal, Microbial Sensitivity Tests, Yeasts isolation & purification, Antifungal Agents pharmacology, Fungi drug effects, Rheiformes microbiology, Yeasts drug effects
- Abstract
Opportunistic yeasts and yeast-like fungi have been recognized as important pathogens in high-risk patients. This study aimed to evaluate the presence of these microorganisms in the microbiota of captive rheas and to investigate the antifungal susceptibility of the isolated strains. Isolates representing Magnusiomyces capitatus (Geotrichum capitatum, n = 11), Trichosporon mucoides (n = 11), Trichosporon asteroides (n = 5), Rhodotorula mucilaginosa (n = 4), Trichosporon asahii (n = 3), Trichosporon cutaneum (n = 3), and Trichosporon ovoides (n = 3) were obtained from the oropharynx, cloaca, and feces of 58 animals. Most of the isolates were susceptible to antifungals in vitro; however, resistance against fluconazole (n = 1) and itraconazole (n = 2) was detected among T. mucoides. This study indicates that healthy rheas can be reservoirs of opportunistic pathogens. Primary resistance to azoles in T. mucoides obtained from these animals demonstrates the potential risk to humans.
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- 2013
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43. Azole-resistant Candida albicans from a wild Brazilian porcupine (Coendou prehensilis): a sign of an environmental imbalance?
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Castelo-Branco DS, Brilhante RS, Paiva MA, Teixeira CE, Caetano EP, Ribeiro JF, Cordeiro RA, Sidrim JJ, Monteiro AJ, and Rocha MF
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- Animals, Brazil, Candida albicans classification, Candida albicans genetics, Microbial Sensitivity Tests, Molecular Typing, Mycological Typing Techniques, Random Amplified Polymorphic DNA Technique, Antifungal Agents pharmacology, Azoles pharmacology, Candida albicans drug effects, Candida albicans isolation & purification, Drug Resistance, Fungal, Porcupines microbiology
- Abstract
This study aimed at evaluating the in vitro antifungal susceptibility of Candida albicans isolates obtained during necropsy of a wild Brazilian porcupine and the mechanism of azole resistance. Initially, we investigated the in vitro susceptibility of the three isolates to amphotericin B, caspofungin, fluconazole, itraconazole, ketoconazole and voriconazole. Afterwards, three sub-inhibitory concentrations (47, 21 and 12 mg/l) of promethazine, an efflux pump inhibitor, were tested in combination with the antifungal drugs in order to evaluate the role of these pumps in the development of antifungal resistance. In addition, the three isolates were submitted to RAPD-PCR and M13-fingerprinting analyses. The minimum inhibitory concentrations (MICs) obtained with the isolates were 1, 0.03125, 250, 125, 8 and 250 mg/l for amphotericin B, caspofungin, fluconazole, itraconazole, ketoconazole and voriconazole, respectively, and the isolates were found to be resistant to all tested azoles. The addition of the three subinhibitory concentrations of promethazine resulted in statistically significant (P < 0.05) reductions in the MICs for all tested drugs, with decreases to azoles being statistically greater than those for amphotericin B and caspofungin (P < 0.05). The molecular analyses showed a genetic similarity among the three tested isolates, suggesting the occurrence of candidemia in the studied animal. These findings highlight the importance of monitoring antifungal susceptibility of Candida spp. from veterinary sources, especially as they may indicate the occurrence of primary azole resistance even in wild animals.
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- 2013
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44. Genetic diversity of Coccidioides posadasii from Brazil.
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Brilhante RS, de Lima RA, Ribeiro JF, de Camargo ZP, Castelo-Branco Dde S, Grangeiro TB, Cordeiro Rde A, Gadelha Rocha MF, and Sidrim JJ
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- Base Sequence, Brazil epidemiology, Coccidioides classification, Coccidioides isolation & purification, Coccidioidomycosis epidemiology, DNA Fingerprinting, DNA, Fungal chemistry, DNA, Fungal genetics, DNA, Ribosomal Spacer chemistry, DNA, Ribosomal Spacer genetics, Genotype, Molecular Sequence Data, Phylogeny, Polymorphism, Single Nucleotide, Random Amplified Polymorphic DNA Technique, Sequence Analysis, DNA, Coccidioides genetics, Coccidioidomycosis microbiology, Genetic Variation
- Abstract
Studies of the genetic variation within populations of Coccidioides posadasii are scarce, especially for those recovered from South America. Understanding the distribution of genotypes among populations is important for epidemiological surveillance. This study evaluated the genetic diversity of 18 Brazilian strains of C. posadasii through the sequencing of the 18-28S region of nuclear rDNA, as well as through RAPD and M13-PCR fingerprinting techniques. The sequences obtained were compared to Coccidioides spp. previously deposited in GenBank. The MEGA5 program was used to perform phylogenetic analyses. Within the C. posadasii clade, a single cluster was observed, containing seven isolates from Ceará, which presented a single nucleotide polymorphism. These isolates were from the same geographical area. The strains of C. posadasii showed a lower rate of genetic diversity in the ITS1 and ITS2 regions. The results of M13 and RAPD-PCR fingerprinting indicated a similar electrophoretic profile. No differences between clinical and environmental isolates were detected. This was the first study assessing the genetic variability of a larger number of C. posadasii isolates from Brazil.
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- 2013
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45. Ciprofloxacin shows synergism with classical antifungals against Histoplasma capsulatum var. capsulatum and Coccidioides posadasii.
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Brilhante RS, Caetano EP, Sidrim JJ, Cordeiro RA, Camargo ZP, Fechine MA, Lima RA, Castelo Branco DS, Marques FJ, Mesquita JR, Lima DT, Monteiro AJ, and Rocha MF
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- Caspofungin, Coccidioides growth & development, Drug Evaluation, Preclinical, Drug Synergism, Echinocandins pharmacology, Histoplasma growth & development, Lipopeptides, Microbial Sensitivity Tests, Mycelium drug effects, Pyrimidines pharmacology, Triazoles pharmacology, Voriconazole, Antifungal Agents pharmacology, Ciprofloxacin pharmacology, Coccidioides drug effects, Histoplasma drug effects
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This study evaluated the in vitro interaction between ciprofloxacin (CIP) and classical antifungals against Histoplasma capsulatum var. capsulatum in mycelial (n = 16) and yeast-like forms (n = 9) and Coccidioides posadasii in mycelial form (n = 16). This research was conducted through broth microdilution and macrodilution, according to Clinical Laboratory Standards Institute. Inocula were prepared to obtain from 0.5 × 10(3) to 2.5 × 10(4) cfu ml(-1) for H. capsulatum and from 10(3) to 5 × 10(3) cfu ml(-1) for C. posadasii. Initially, minimum inhibitory concentration (MIC) for each drug alone was determined. Then, these MICs were used as the highest concentration for each drug during combination assays. The procedures were performed in duplicate. For all combination assays, MICs were defined as the lowest concentration capable of inhibiting 80% of visible fungal growth, when compared to the drug-free control. Drug interaction was evaluated by paired sample t-Student test. The obtained data showed a significant MIC reduction for most tested combinations of CIP with antifungals, except for that of CIP and voriconazole against yeast-like H. capsulatum. This study brings potential alternatives for the treatment of histoplasmosis and coccidioidomycosis, raising the possibility of using CIP as an adjuvant antifungal therapy, providing perspectives to delineate in vivo studies., (© 2012 Blackwell Verlag GmbH.)
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- 2013
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46. Glucose and lactose as cryoprotectants for fungal strains immobilised in sodium alginate: an emphasis on the conservation of the zygomycetes Rhizopus and Mucor.
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Rocha MF, Lima DT, Brilhante RS, Cordeiro RA, Monteiro AJ, Teixeira CE, Ribeiro JF, Castelo-Branco DS, and Sidrim JJ
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- Cell Adhesion drug effects, Cells, Immobilized drug effects, Cryopreservation methods, Culture Media metabolism, Glucuronic Acid metabolism, Hexuronic Acids metabolism, Microbial Viability, Mucor drug effects, Mucor metabolism, Rhizopus metabolism, Temperature, Alginates metabolism, Cryoprotective Agents pharmacology, Glucose pharmacology, Lactose pharmacology, Rhizopus drug effects
- Abstract
This research aimed at investigating the cryoprotectant action of glucose and lactose on strains of Malassezia spp. and zygomycetes immobilised in sodium alginate. Twelve strains of Malassezia spp. (nine M. furfur, two M. globosa and one M. sympodialis) and 12 zygomycetes (five Rhizopus oryzae and seven Mucor hiemales) were immobilised in sodium alginate, within plastic beads, maintained in appropriate media containing glucose and lactose at concentrations of 9% and 23% and preserved at temperatures of -20 and -80 °C. Strain viability was evaluated from 15 to 270 days of storage, through the observation of macro-micromorphologic characteristics. The Malassezia spp. strains were only viable until 90 days of storage, whereas for zygomycetes, viable strains were observed until after 270 days of storage at -80 °C, in the media containing 23% glucose or lactose. The use of 23% glucose or lactose at -80 °C in a sodium alginate cell immobilisation system is efficient for cryopreserving zygomycetes. This research creates perspectives for the use of glucose and lactose in sodium alginate cell immobilisation systems for the preservation of fungi with low viability., (© 2012 Blackwell Verlag GmbH.)
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- 2013
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47. Effect of farnesol on growth, ergosterol biosynthesis, and cell permeability in Coccidioides posadasii.
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Brilhante RS, de Lima RA, Caetano EP, Leite JJ, Castelo-Branco Dde S, Ribeiro JF, Bandeira Tde J, Cordeiro Rde A, Monteiro AJ, Sidrim JJ, and Rocha MF
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- Cell Membrane Permeability drug effects, Coccidioides growth & development, Coccidioides metabolism, Drug Synergism, Drug Therapy, Combination, Ergosterol biosynthesis, Microbial Sensitivity Tests, Osmolar Concentration, Osmotic Pressure, Sodium Chloride chemistry, Antifungal Agents pharmacology, Coccidioides drug effects, Ergosterol antagonists & inhibitors, Farnesol pharmacology, Fluconazole pharmacology
- Abstract
Coccidioidomycosis is a systemic mycosis caused by the dimorphic fungi Coccidioides spp. The treatment for chronic and/or disseminated coccidioidomycosis can be prolonged and complicated. Therefore, the search for new drugs is necessary. Farnesol is a precursor in the sterol biosynthesis pathway that has been shown to present antifungal activity. Thus, the objective of this study was to evaluate the in vitro antifungal activity of farnesol alone and in combination with antifungal agents against clinical and environmental strains of Coccidioides posadasii as well as to determine their effect on the synthesis of ergosterol and on cell permeability. This study employed the broth macrodilution method to determine the MIC of farnesol against 18 strains of C. posadasii. Quantification of ergosterol was performed with 10 strains of C. posadasii after exposure to subinhibitory concentrations of farnesol. Finally, the activity of farnesol was evaluated in the presence of osmotic stress, induced by the addition of NaCl to the culture medium, during the susceptibility tests. The results showed that farnesol exhibited low MICs (ranging from 0.00171 to 0.01369 mg/liter) against all tested strains. The combination of farnesol with the antifungals showed synergistic effects (fractional inhibitory concentration index [FICI] ≤ 0.5). As for the ergosterol quantification, it was observed that exposure to subinhibitory concentrations of farnesol decreased the amount of ergosterol extracted from the fungal cells. Furthermore, farnesol also showed lower MIC values when the strains were subjected to osmotic stress, indicating the action of this compound on the fungal membrane. Thus, due to the high in vitro antifungal activity, this work brings perspectives for the performance of in vivo studies to further elucidate the effects of farnesol on the host cells.
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- 2013
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48. Antifolates inhibit Cryptococcus biofilms and enhance susceptibility of planktonic cells to amphotericin B.
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de Aguiar Cordeiro R, Mourão CI, Rocha MF, de Farias Marques FJ, Teixeira CE, de Oliveira Miranda DF, Neto LV, Brilhante RS, de Jesus Pinheiro Gomes Bandeira T, and Sidrim JJ
- Subjects
- Cryptococcosis microbiology, Cryptococcus gattii physiology, Cryptococcus neoformans isolation & purification, Cryptococcus neoformans physiology, Drug Combinations, Environmental Microbiology, Humans, Microbial Sensitivity Tests, Pyrimethamine metabolism, Sulfadoxine metabolism, Trimethoprim, Sulfamethoxazole Drug Combination metabolism, Amphotericin B metabolism, Antifungal Agents metabolism, Biofilms drug effects, Cryptococcus gattii drug effects, Cryptococcus neoformans drug effects, Folic Acid Antagonists metabolism
- Abstract
The Cryptococcus neoformans species complex contains the most important agents of fungal meningoencephalitis. Therapeutic choices are limited and issues related to toxicity and resistance to antifungals have been described. The present study evaluated the inhibitory effect of the antifolate combinations sulfamethoxazole-trimethoprim (SMX/TMP) and sulfadiazine-pyrimethamine (SDZ/PYR) against planktonic cells and biofilms of C. neoformans and C. gattii. The influence of the antifolate combinations on the amphotericin minimum inhibitory concentration (MIC) of planktonic cells was also investigated. In addition, the effect of these combinations on the cellular ergosterol content of planktonic cells was studied. Strains of C. neoformans (n = 15) and C. gattii (n = 15) obtained from environmental or clinical sources were evaluated by the broth microdilution method. SMX/TMP and SDZ/PYR showed antifungal activity against free living cells and sessile cells of Cryptococcus spp. Moreover, planktonic cells showed increased susceptibility to amphotericin B after pre-incubation with sub-inhibitory concentrations of SMX/TMP or SDZ/PYR. The drug combinations SMX/TMP and SDZ/PYR were able to prevent the biofilm formation and showed inhibitory effect against mature biofilms of both species. Additionally, the study showed that antifolate drugs reduced the ergosterol content in C. neoformans and C. gattii planktonic cells. Our results highlight the antifungal potential of antifolate drugs.
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- 2013
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49. Anti-inflammatory and immunomodulatory effect of an extract of Coccidioides posadasii in experimental arthritis.
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Pinto AC, Cordeiro Rde A, Sidrim JJ, Leite AK, Leite AC, Girão VC, Brilhante RS, Rocha MF, Cunha Fde Q, and Rocha FA
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- Administration, Oral, Animals, Anti-Inflammatory Agents isolation & purification, Arthritis pathology, Biological Products isolation & purification, Bursa, Synovial pathology, Cytokines analysis, Disease Models, Animal, Fungal Proteins administration & dosage, Fungal Proteins isolation & purification, Histocytochemistry, Immunohistochemistry, Immunologic Factors isolation & purification, Injections, Intraperitoneal, Leukocytes immunology, Male, Mice, Rats, Rats, Wistar, Anti-Inflammatory Agents administration & dosage, Arthritis drug therapy, Biological Products administration & dosage, Coccidioides chemistry, Immunologic Factors administration & dosage
- Abstract
Trying to surpass host defenses, fungal infections alter the immune response. Components from nonpathogenic fungi present therapeutic anti-inflammatory and immunomodulating activities. This study reveals that proteins present in a Coccidioides posadasii extract provide anti-inflammatory benefit in experimental arthritis. Zymosan was given intra-articularly to rats and mice, and groups were pretreated with C. posadasii extract either per os or intraperitoneally. Controls received the vehicle. Acute hypernociception was evaluated using articular incapacitation and von Frey methods. Cell influx and cytokine levels were assessed in joint exudates. Joint damage was evaluated by histopathology and determination of glycosaminoglycan content of the cartilage. Synovia was evaluated for cell death and inducible nitric oxide synthase (iNOS) expression using TUNEL and immunohistochemistry, respectively. Pretreatment with C. posadasii extract significantly inhibited acute and chronic cell influx, hypernociception, and provoked reduction of glycosaminoglycan loss while reducing chronic synovitis, cell death, and iNOS expression. Reduction/alkylation of C. posadasii extract abrogated these effects. C. posadasii administration did not alter TNF-α, IL-1β, IL-17, and γ-interferon levels, whereas IL-10 levels were significantly reduced. Data reveal that a C. posadasii extract reduces iNOS expression that is associated with inhibition of synovial apoptosis and decrease in IL-10 levels released into zymosan-inflamed joints. Characterization of active components excluded charged carbohydrates while pointing to a protein as responsible for these effects. In summary, systemic administration of components from a pathogenic fungus provides anti-inflammatory effects, being species-independent and orally active. Besides adding to understand host response against fungi, the results may lead to therapeutic implications.
- Published
- 2013
- Full Text
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50. Synergistic effects of amiodarone and fluconazole on Candida tropicalis resistant to fluconazole.
- Author
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da Silva CR, de Andrade Neto JB, Sidrim JJ, Angelo MR, Magalhães HI, Cavalcanti BC, Brilhante RS, Macedo DS, de Moraes MO, Lobo MD, Grangeiro TB, and Nobre Júnior HV
- Subjects
- Drug Resistance, Fungal, Drug Synergism, Microbial Sensitivity Tests, Amiodarone pharmacology, Antifungal Agents pharmacology, Candida tropicalis drug effects, Candida tropicalis pathogenicity, Fluconazole pharmacology
- Abstract
There have recently been significant increases in the prevalence of systemic invasive fungal infections. However, the number of antifungal drugs on the market is limited in comparison to the number of available antibacterial drugs. This fact, coupled with the increased frequency of cross-resistance, makes it necessary to develop new therapeutic strategies. Combination drug therapies have become one of the most widely used and effective strategies to alleviate this problem. Amiodarone (AMD) is classically used for the treatment of atrial fibrillation and is the drug of choice for patients with arrhythmia. Recent studies have shown broad antifungal activity of the drug when administered in combination with fluconazole (FLC). In the present study, we induced resistance to fluconazole in six strains of Candida tropicalis and evaluated potential synergism between fluconazole and amiodarone. The evaluation of drug interaction was determined by calculating the fractional inhibitory concentration and by performing flow cytometry. We conclude that amiodarone, when administered in combination with fluconazole, exhibits activity against strains of C. tropicalis that are resistant to fluconazole, which most likely occurs via changes in the integrity of the yeast cell membrane and the generation of oxidative stress, mitochondrial dysfunction, and DNA damage that could lead to cell death by apoptosis.
- Published
- 2013
- Full Text
- View/download PDF
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