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1.
Microb Pathog ; 177: 106032, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36804526

RESUMO

Bats (Chiroptera) are flying mammals of great biodiversity and habits. These characteristics contribute for them being natural reservoirs and part of the epidemiological cycle of several potentially zoonotic pathogens, such as viruses, protozoa, fungi and bacteria. Brazil hosts approximately 15% of the world's bat diversity, with 181 distinct species, 68 genera and 9 families. About 60% of infectious diseases in humans are of zoonotic origin and, in the last decades, the detection of zoonotic pathogens in bats and their environment has been reported, such as Rabies virus (RABV) and Histoplasma capsulatum. Thus, the aim of this work was to review the reports of zoonotic pathogens associated with bats in Brazil in the past ten years. We reviewed the main pathogenic microorganisms described and the species of bats most frequently involved in the epidemiological cycles of these zoonotic agents. The obtained data show an upward trend in the detection of zoonotic pathogens in Brazilian bats, such as RABV, Bartonella sp., Histoplasma capsulatum and Leishmania spp., with emphasis on the bat species Artibeus lituratus, Carollia perspicillata, Desmodus rotundus and Molossus molossus. These findings highlight the importance of monitoring bat-associated microrganisms to early identify pathogens that may threaten bat populations, including potentially zoonotic microrganisms, emphasizing the importance of the One Health approach to prevent and mitigate the risks of the emergence of zoonotic diseases.


Assuntos
Quirópteros , Vírus da Raiva , Vírus , Animais , Humanos , Brasil/epidemiologia , Zoonoses/epidemiologia , Vírus/genética , Filogenia
2.
J Appl Microbiol ; 131(3): 1487-1497, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33556197

RESUMO

AIM: This study aimed to assess an ex situ model of biofilm-associated wounds on porcine skin for the study of Staphylococcus aureus and Pseudomonas aeruginosa biofilms in a host-like environment, after 48 to 120 h of incubation. MATERIAL AND RESULTS: Ex situ and in vitro biofilms were comparatively analysed. Overall, CFU-counts and matrix quantification yielded significantly (P < 0·05) higher results for ex situ than in vitro biofilms. Confocal microscopy revealed greater (P < 0·05) biomass and thickness at 48-72 h and greater (P < 0·05) robustness at 72 h of growth. S. aureus ex situ biofilms produced less (P < 0·05) siderophore and proteases than in vitro biofilms, while P. aeruginosa ex situ biofilms produced more (P < 0·05) siderophores and less proteases than in vitro biofilms. CONCLUSIONS: Biofilms grown ex situ present a greater amount of bacterial cells and polymeric matrix than their in vitro counterparts, reaching maturity at 72 h of growth. Moreover the production of virulence factors differs between ex situ and in vitro biofilms. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings emphasize the importance of using ex situ biofilm models, once they mimic in vivo conditions. The use of these models brings perspectives for the pursuit of therapeutic alternatives, as tests may be performed in a host-like environment.


Assuntos
Biofilmes , Pseudomonas aeruginosa , Pele/microbiologia , Staphylococcus aureus , Animais , Técnicas In Vitro , Infecções por Pseudomonas , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/patogenicidade , Infecções Estafilocócicas , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/patogenicidade , Suínos , Ferimentos e Lesões/microbiologia
3.
Mycoses ; 59(5): 281-90, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26864989

RESUMO

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.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Clorobenzenos/farmacologia , Fluconazol/farmacologia , Fungicidas Industriais/farmacologia , Triazóis/farmacologia , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Antialérgicos/farmacologia , Candida/genética , Resistência Microbiana a Medicamentos , Ergosterol/análise , Regulação Fúngica da Expressão Gênica , Humanos , Itraconazol/farmacologia , Malation/farmacologia , Testes de Sensibilidade Microbiana , Prometazina/farmacologia , Rodaminas , Esterol 14-Desmetilase/genética , Voriconazol/farmacologia
4.
J Appl Microbiol ; 120(3): 600-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26669506

RESUMO

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.


Assuntos
Biofilmes/efeitos dos fármacos , Burkholderia pseudomallei/efeitos dos fármacos , Farneseno Álcool/farmacologia , Melioidose/microbiologia , Amoxicilina/farmacologia , Antibacterianos/farmacologia , Burkholderia pseudomallei/fisiologia , Ceftazidima/farmacologia , Humanos , Melioidose/tratamento farmacológico , Testes de Sensibilidade Microbiana/métodos , Combinação Trimetoprima e Sulfametoxazol
5.
Chemotherapy ; 58(5): 337-40, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23171666

RESUMO

BACKGROUND: The aim of this work was to evaluate the interactions between aminoglycosides and the ethyl-acetate fraction of the fern Lygodium venustum SW (EAFLV) METHODS: The ethyl-acetate fraction was obtained from the ethanol extract of L. venustum and was assayed via the checkerboard method associated with aminoglycosides against two bacterial strains multiresistant to antibiotics. RESULTS: The antibiotic activity of all drugs, when associated with the ethyl-acetate fraction, was enhanced in an additive manner, except for the association between EAFLV and amikacin, which showed a synergistic interaction against the Escherichia coli strain. CONCLUSIONS: The results indicated that L. venustum can be a source of secondary metabolites to be used in association with antibiotics like aminoglycosides in antibiotic chemotherapy against resistant bacteria.


Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Produtos Biológicos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Gleiquênias/química , Fenóis/farmacologia , Amicacina/farmacologia , Aminoglicosídeos/química , Antibacterianos/química , Produtos Biológicos/química , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Fenóis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos
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