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1.
J Appl Microbiol ; 131(3): 1487-1497, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33556197

RESUMEN

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.


Asunto(s)
Biopelículas , Pseudomonas aeruginosa , Piel/microbiología , Staphylococcus aureus , Animales , Técnicas In Vitro , Infecciones por Pseudomonas , Pseudomonas aeruginosa/crecimiento & desarrollo , Pseudomonas aeruginosa/patogenicidad , Infecciones Estafilocócicas , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/patogenicidad , Porcinos , Heridas y Lesiones/microbiología
2.
Stud Mycol ; 97: 100095, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33335607

RESUMEN

Histoplasmosis is a serious infectious disease in humans caused by Histoplasma spp. (Onygenales), whose natural reservoirs are thought to be soil enriched with bird and bat guano. The true global burden of histoplasmosis is underestimated and frequently the pulmonary manifestations are misdiagnosed as tuberculosis. Molecular data on epidemiology of Histoplasma are still scarce, even though there is increasing recognition of histoplasmosis in recent years in areas distant from the traditional endemic regions in the Americas. We used multi-locus sequence data from protein coding loci (ADP-ribosylation factor, H antigen precursor, and delta-9 fatty acid desaturase), DNA barcoding (ITS1/2+5.8s), AFLP markers and mating type analysis to determine the genetic diversity, population structure and recognise the existence of different phylogenetic species among 436 isolates of Histoplasma obtained globally. Our study describes new phylogenetic species and the molecular characteristics of Histoplasma lineages causing outbreaks with a high number of severe outcomes in Northeast Brazil between 2011 and 2015. Genetic diversity levels provide evidence for recombination, common ancestry and clustering of Brazilian isolates at different geographic scales with the emergence of LAm C, a new genotype assigned to a separate population cluster in Northeast Brazil that exhibited low diversity indicative of isolation. The global survey revealed that the high genetic variability among Brazilian isolates along with the presence of divergent cryptic species and/or genotypes may support the hypothesis of Brazil being the center of dispersion of Histoplasma in South America, possibly with the contribution of migratory hosts such as birds and bats. Outside Brazil, the predominant species depends on the region. We confirm that histoplasmosis has significantly broadened its area of occurrence, an important feature of emerging pathogens. From a practical point of view, our data point to the emergence of histoplasmosis caused by a plethora of genotypes, and will enable epidemiological analysis focused on understanding the processes that lead to histoplasmosis. Further, the description of this diversity opens avenues for comparative genomic studies, which will allow progress toward a consensus taxonomy, improve understanding of the presence of hybrids in natural populations of medically relevant fungi, test reproductive barriers and to explore the significance of this variation.

3.
Artículo en Inglés | MEDLINE | ID: mdl-28739796

RESUMEN

Clinical and Laboratory Standards Institute (CLSI) conditions for testing the susceptibilities of pathogenic Sporothrix species to antifungal agents are based on a collaborative study that evaluated five clinically relevant isolates of Sporothrixschenckii sensu lato and some antifungal agents. With the advent of molecular identification, there are two basic needs: to confirm the suitability of these testing conditions for all agents and Sporothrix species and to establish species-specific epidemiologic cutoff values (ECVs) or breakpoints (BPs) for the species. We collected available CLSI MICs/minimal effective concentrations (MECs) of amphotericin B, five triazoles, terbinafine, flucytosine, and caspofungin for 301 Sporothrix schenckii sensu stricto, 486 S. brasiliensis, 75 S. globosa, and 13 S. mexicana molecularly identified isolates. Data were obtained in 17 independent laboratories (Australia, Europe, India, South Africa, and South and North America) using conidial inoculum suspensions and 48 to 72 h of incubation at 35°C. Sufficient and suitable data (modal MICs within 2-fold concentrations) allowed the proposal of the following ECVs for S. schenckii and S. brasiliensis, respectively: amphotericin B, 4 and 4 µg/ml; itraconazole, 2 and 2 µg/ml; posaconazole, 2 and 2 µg/ml; and voriconazole, 64 and 32 µg/ml. Ketoconazole and terbinafine ECVs for S. brasiliensis were 2 and 0.12 µg/ml, respectively. Insufficient or unsuitable data precluded the calculation of ketoconazole and terbinafine (or any other antifungal agent) ECVs for S. schenckii, as well as ECVs for S. globosa and S. mexicana These ECVs could aid the clinician in identifying potentially resistant isolates (non-wild type) less likely to respond to therapy.


Asunto(s)
Anfotericina B/farmacología , Antifúngicos/farmacología , Equinocandinas/farmacología , Flucitosina/farmacología , Lipopéptidos/farmacología , Naftalenos/farmacología , Sporothrix/efectos de los fármacos , Esporotricosis/tratamiento farmacológico , Triazoles/farmacología , Caspofungina , Humanos , Pruebas de Sensibilidad Microbiana , Sporothrix/clasificación , Sporothrix/aislamiento & purificación , Terbinafina
4.
J Appl Microbiol ; 120(3): 600-6, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26669506

RESUMEN

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.


Asunto(s)
Biopelículas/efectos de los fármacos , Burkholderia pseudomallei/efectos de los fármacos , Farnesol/farmacología , Melioidosis/microbiología , Amoxicilina/farmacología , Antibacterianos/farmacología , Burkholderia pseudomallei/fisiología , Ceftazidima/farmacología , Humanos , Melioidosis/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana/métodos , Combinación Trimetoprim y Sulfametoxazol
5.
J Appl Microbiol ; 119(4): 962-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26178247

RESUMEN

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.


Asunto(s)
Antifúngicos/farmacología , Coccidioides/efectos de los fármacos , Ergosterol/biosíntesis , Histoplasma/crecimiento & desarrollo , Levamisol/farmacología , Fosforilcolina/análogos & derivados , Permeabilidad de la Membrana Celular/efectos de los fármacos , Coccidioides/crecimiento & desarrollo , Coccidioides/metabolismo , Histoplasma/efectos de los fármacos , Histoplasma/metabolismo , Pruebas de Sensibilidad Microbiana , Fosforilcolina/farmacología
6.
Mycopathologia ; 180(3-4): 277-80, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25898770

RESUMEN

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.


Asunto(s)
Antifúngicos/farmacología , Azoles/farmacología , Candida albicans/aislamiento & purificación , Farmacorresistencia Fúngica , Cabras/microbiología , Ovinos/microbiología , Animales , Brasil , Boca/microbiología , Cavidad Nasal/microbiología , Recto/microbiología , Rhodotorula/aislamiento & purificación , Trichosporon/aislamiento & purificación
7.
Eur J Clin Microbiol Infect Dis ; 32(4): 557-64, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23192488

RESUMEN

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.


Asunto(s)
Anfotericina B/metabolismo , Antifúngicos/metabolismo , Biopelículas/efectos de los fármacos , Cryptococcus gattii/efectos de los fármacos , Cryptococcus neoformans/efectos de los fármacos , Antagonistas del Ácido Fólico/metabolismo , Criptococosis/microbiología , Cryptococcus gattii/fisiología , Cryptococcus neoformans/aislamiento & purificación , Cryptococcus neoformans/fisiología , Combinación de Medicamentos , Microbiología Ambiental , Humanos , Pruebas de Sensibilidad Microbiana , Pirimetamina/metabolismo , Sulfadoxina/metabolismo , Combinación Trimetoprim y Sulfametoxazol/metabolismo
8.
Med Mycol ; 51(5): 555-60, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23286353

RESUMEN

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.


Asunto(s)
Antifúngicos/farmacología , Azoles/farmacología , Candida albicans/efectos de los fármacos , Candida albicans/aislamiento & purificación , Farmacorresistencia Fúngica , Puercoespines/microbiología , Animales , Brasil , Candida albicans/clasificación , Candida albicans/genética , Pruebas de Sensibilidad Microbiana , Tipificación Molecular , Técnicas de Tipificación Micológica , Técnica del ADN Polimorfo Amplificado Aleatorio
9.
Mycoses ; 56(3): 397-401, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23205615

RESUMEN

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.


Asunto(s)
Antifúngicos/farmacología , Ciprofloxacina/farmacología , Coccidioides/efectos de los fármacos , Histoplasma/efectos de los fármacos , Caspofungina , Coccidioides/crecimiento & desarrollo , Evaluación Preclínica de Medicamentos , Sinergismo Farmacológico , Equinocandinas/farmacología , Histoplasma/crecimiento & desarrollo , Lipopéptidos , Pruebas de Sensibilidad Microbiana , Micelio/efectos de los fármacos , Pirimidinas/farmacología , Triazoles/farmacología , Voriconazol
10.
Antimicrob Agents Chemother ; 56(4): 2198-200, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22290941

RESUMEN

This study aimed to evaluate the in vitro combination of farnesol and ß-lactams against Burkholderia pseudomallei. A total of 12 ß-lactamase-positive strains were tested according to CLSI standards. All strains were inhibited by farnesol, with MICs ranging from 75 to 150 µM. The combination of this compound with ß-lactams resulted in statistically significant ß-lactam MIC reduction (P ≤ 0.05). This study provides new perspectives for the use of farnesol combined with ß-lactam antibiotics against strains of B. pseudomallei.


Asunto(s)
Antibacterianos/farmacología , Burkholderia pseudomallei/efectos de los fármacos , Farnesol/farmacología , beta-Lactamas/farmacología , Burkholderia pseudomallei/crecimiento & desarrollo , Farmacorresistencia Bacteriana , Sinergismo Farmacológico , Pruebas de Sensibilidad Microbiana , beta-Lactamasas/metabolismo
11.
Can J Microbiol ; 58(7): 932-6, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22716223

RESUMEN

The effects of the protease inhibitors saquinavir, darunavir, ritonavir, and indinavir on growth inhibition, protease and phospholipase activities, as well as capsule thickness of Cryptococcus neoformans were investigated. Viral protease inhibitors did not reduce fungal growth when tested in concentrations ranging from 0.001 to 1.000 mg/L. A tendency toward increasing phospholipase activity was observed with the highest tested drug concentration in a strain-specific pattern. However, these drugs reduced protease activity as well as capsule production. Our results confirm a previous finding that antiretroviral drugs affect the production of important virulence factors of C. neoformans.


Asunto(s)
Antirretrovirales/farmacología , Cryptococcus neoformans/efectos de los fármacos , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Inhibidores de Proteasas/farmacología , Cryptococcus neoformans/enzimología , Cryptococcus neoformans/patogenicidad , Indinavir/farmacología , Ritonavir/farmacología , Saquinavir/farmacología , Factores de Virulencia/genética
12.
J Appl Microbiol ; 108(5): 1751-6, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19863685

RESUMEN

AIMS: To investigate the presence of fungi during three human decomposition stages: bloated, putrefaction and skeletonization. METHODS AND RESULTS: The samples were gathered in the city of Fortaleza, Ceará, Brazil, from the public morgue and cemeteries. The material was submitted to conventional mycological procedures by direct examination and macro/micro morphological and biochemical analyses. The main fungi isolated were Aspergillus spp., Penicillium spp. and Candida spp. in the bloated stage (n = 34 cadavers) and in the putrefaction stage (n = 6 cadavers), while in the skeletonization stage (n = 20 cadavers), the main fungi were Aspergillus spp., Penicillium spp. and Mucor sp. CONCLUSIONS: Aspergillus, Penicillium and Candida species were associated with decomposed human cadavers. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings enable tracing out the profile of fungal communities of human cadavers for the first time. However, much more research will be necessary to develop this new segment of mycology and to enable its routine use in forensic science.


Asunto(s)
Ecosistema , Ciencias Forenses , Hongos Mitospóricos/fisiología , Cambios Post Mortem , Aspergillus/aislamiento & purificación , Aspergillus/fisiología , Biodiversidad , Brasil , Candida/aislamiento & purificación , Candida/fisiología , Humanos , Hongos Mitospóricos/aislamiento & purificación , Penicillium/aislamiento & purificación , Penicillium/fisiología
13.
J Appl Microbiol ; 107(6): 2063-9, 2009 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-19558469

RESUMEN

AIMS: The purpose of this study was to demonstrate the usefulness of lectin obtained from Talisia esculenta (TEL) seeds as a tool to recognize and study Microsporum canis. For this purpose, we investigated the antifungal and marker action of this lectin and the relationship of these effects with the presence of carbohydrates on the structure of this fungus. METHODS AND RESULTS: The in vitro antifungal activity of TEL was analysed by broth microdilution assay. In addition, TEL was assessed against the arthroconidia present on hairs obtained from infected dogs and cats. The affinity of fluorescein isothiocyanate (FITC)-labelled TEL for macroconidia and arthroconidia of M. canis was also tested. The effects of TEL on the growth of the M. canis strains began with 0.125 mg ml(-1), and 100% inhibition was obtained with a concentration of 2 mg ml(-1). The addition of carbohydrates, especially N-acetyl-glucosamine and d-mannose, inhibited these antifungal effects. TEL was able to inhibit the growth of arthroconidial chitin-rich forms of M. canis obtained from hairs of infected animals and strains cultured in Sabouraud agar. FITC-labelled TEL efficiently marked macroconidial and arthroconidial forms of M. canis, as shown by fluorescent microscopy. CONCLUSIONS: These results show that the inhibitory effects of TEL on M. canis growth may be related to the interaction of lectin with the carbohydrates present at the micro-organism's surface, mainly D-mannose and N-acetyl-glucosamine. SIGNIFICANCE AND IMPACT OF THE STUDY: Talisia esculenta can be used as an important tool in the biochemical study of M. canis or as a molecule to recognize this dermatophyte in infected tissue.


Asunto(s)
Antifúngicos/farmacología , Enfermedades de los Gatos/microbiología , Dermatomicosis/veterinaria , Enfermedades de los Perros/microbiología , Microsporum/efectos de los fármacos , Microsporum/aislamiento & purificación , Lectinas de Plantas/farmacología , Sapindaceae/química , Animales , Bioensayo , Gatos , Dermatomicosis/microbiología , Perros , Cabello/microbiología , Pruebas de Sensibilidad Microbiana , Microsporum/crecimiento & desarrollo , Semillas/química , Esporas Fúngicas/efectos de los fármacos
14.
J Med Entomol ; 46(4): 895-9, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19645295

RESUMEN

The aim of this study was to evaluate the presence of filamentous fungi and yeasts on the external surface of ants at hospitals. From March 2007 to February 2008, 2,899 ants were evaluated in two public hospitals in the city of Fortaleza, Ceará, in northeastern Brazil. The ants were attracted by nontoxic baits, distributed within critical and semicritical hospital areas. The fungi were identified through macro- and micromorphological analysis, biochemical profile, and growth in chromogenic medium. From this study, 5 genera and 13 species of ants were identified, from critical (8% of the collected ants) and semicritical (92%) areas, during the daytime (48%) and nighttime (52%) periods. In the mycological analysis, 75% of the ants were fungi carriers, with the species Tapinoma melanocephalum and species from the genus Pheidole having the most potential as carriers of airborne fungi (75 and 18%, respectively) and yeasts (6 and 1%, respectively). In summary, ants act as carriers of airborne fungi and yeasts, including some pathogenic species.


Asunto(s)
Hormigas/microbiología , Hongos/aislamiento & purificación , Hospitales Públicos , Insectos Vectores/microbiología , Animales , Brasil , Monitoreo del Ambiente , Hongos/clasificación , Infecciones Oportunistas/microbiología , Infecciones Oportunistas/prevención & control
15.
J Appl Microbiol ; 104(5): 1383-90, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18298533

RESUMEN

AIMS: To find new antifungal agents among essential oils from Brazilian Croton species. METHODS AND RESULTS: Plant leaves were steam distilled and the obtained essential oils were analyzed by gas chromatography/mass spectroscopy. The main constituents were estragole and anethole for Croton zehntneri, methyl-eugenol and bicyclogermacrene for Croton nepetaefolius and spathulenol and bicyclogermacrene for Croton argyrophylloides. The antifungal activity of essential oils was evaluated against Candida albicans, Candida tropicalis and Microsporum canis by the agar-well diffusion method and the minimum inhibitory concentration (MIC) by the broth microdilution method. Essential oils of Croton species demonstrated better activity against M. canis. Among the three plants C. argyrophylloides showed the best results, with MIC ranging from 9 to 19 microg ml(-1). The acute administration of the essential oil up to 3 g kg(-1) by the oral route to mice was devoid of overt toxicity. CONCLUSIONS: The studied essential oils are active in vitro against the dermatophyte M. canis and present relative lack of acute toxicity in vivo. SIGNIFICANCE AND IMPACT OF THE STUDY: Because of its antifungal activity and low toxicity, the essential oils of studied Croton species are promising sources for new phytotherapeutic agents to treat dermatophytosis.


Asunto(s)
Antifúngicos/aislamiento & purificación , Croton/fisiología , Aceites Volátiles/aislamiento & purificación , Animales , Antifúngicos/farmacología , Antifúngicos/toxicidad , Brasil , Candida/efectos de los fármacos , Pruebas Antimicrobianas de Difusión por Disco , Femenino , Masculino , Ratones , Pruebas de Sensibilidad Microbiana , Microsporum/efectos de los fármacos , Aceites Volátiles/farmacología , Aceites Volátiles/toxicidad , Pruebas de Toxicidad Aguda
16.
J Mycol Med ; 28(2): 390-392, 2018 Jun.
Artículo en Francés | MEDLINE | ID: mdl-29724543

RESUMEN

Severely immunocompromised patients are at increased risk for uncommon infectious diseases with atypical presentations. Fusarium sp., has been reported in patients with hematological malignancies and prompt diagnosis is necessary due to high mortality. We report a myelodysplastic syndrome (MDS) patient who presented Fusarium solani infection associated with granulocytic sarcoma as an initial presentation of acute myeloid leukemia (AML) transformation. We performed histological examination, immunohistochemistry analysis, culture of the biopsy tissue and DNA sequencing to make a conclusive diagnosis of F. solani and granulocytic sarcoma, reinforcing the necessity of performing complete evaluation of skin lesions in immunocompromised patients.


Asunto(s)
Fusariosis/diagnóstico , Fusarium/aislamiento & purificación , Síndromes Mielodisplásicos/microbiología , Azacitidina/uso terapéutico , Biopsia , Diagnóstico Diferencial , Femenino , Fusarium/efectos de los fármacos , Fusarium/genética , Humanos , Huésped Inmunocomprometido , Leucemia Mieloide Aguda/complicaciones , Persona de Mediana Edad , Micelio/ultraestructura , Sarcoma Mieloide/diagnóstico , Sarcoma Mieloide/microbiología , Sarcoma Mieloide/radioterapia , Análisis de Secuencia de ADN , Piel/microbiología , Piel/patología
17.
J Microbiol Methods ; 69(1): 218-21, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17254654

RESUMEN

We describe simple and cost-effective methods using carbohydrates to improve the in vitro viability of dermatophytes. Glucose and sucrose in different concentrations (3, 6, 9 and 12%) were used to maintain fifteen strains of M. canis and T. mentagrophytes var. mentagrophytes at 4 and -20 degrees C. The strains were phenotypically analyzed before storage and reevaluated at 1, 3, 6 and 9 months. At 1 and 3 months, any alterations in the viability or phenotype pattern of the stored strains were noted. At 6 months, both dermatophytes were 100% viable, when preserved in glucose (3, 6, 9 and 12%) at -20 degrees C. All T. mentagrophytes strains were also viable in sucrose (12%), at 4 degrees C and -20 degrees C. However, sucrose failed to improve the viability of M. canis at both temperatures. At 9 months, the higher viabilities without pleomorphism were seen for both dermatophytes preserved in glucose (9 and 12%) at -20 degrees C.


Asunto(s)
Glucosa/farmacología , Microsporum/citología , Trichophyton/citología , Arthrodermataceae/citología , Arthrodermataceae/efectos de los fármacos , Técnicas de Cultivo de Célula , Microsporum/efectos de los fármacos , Microsporum/ultraestructura , Sacarosa/farmacología , Trichophyton/efectos de los fármacos , Trichophyton/ultraestructura
18.
J Med Microbiol ; 55(Pt 11): 1583-1586, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17030920

RESUMEN

Microsporum canis is the most common species isolated from canine and feline dermatophytosis in the world. However, this study reports a rare case of canine dermatophytosis caused by the anthropophilic dermatophyte Trichophyton tonsurans in the city of Fortaleza, Ceará, Brazil. The fungal characterization was performed by classical mycological examination and by genotypical analysis using the restriction enzymes Sau3A, RsaI, DdeI and EcoRI. The phenotypical characteristics were compatible with T. tonsurans. The results obtained in the genotypical analysis were similar to the digestion pattern of the ITS sequences for T. tonsurans strains. In addition, an antifungal susceptibility test was performed with griseofulvin, ketoconazole and itraconazole. The MICs were 0.5 microg ml(-1) for griseofulvin, 0.25 microg ml(-1) for ketoconazole and 1 microg ml(-1) for itraconazole. This study emphasizes the adaptability of anthropophilic fungi such as T. tonsurans to animal conditions.


Asunto(s)
Dermatomicosis/veterinaria , Enfermedades de los Perros/microbiología , Trichophyton/crecimiento & desarrollo , Animales , ADN de Hongos/química , ADN de Hongos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Dermatomicosis/microbiología , Perros , Femenino , Pruebas de Sensibilidad Microbiana/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , Trichophyton/genética
19.
Vet J ; 172(3): 544-8, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16154787

RESUMEN

To investigate the role of Malassezia pachydermatis as a pathogenic agent in canine otitis, a comparative analysis of isolates from normal and diseased external ear canals in dogs was undertaken. Specimens were collected from the ears of dogs with unilateral or bilateral otitis and from healthy dogs. Mycological analysis was by direct microscopy and fungal culture on Sabouraud's dextrose agar and Dixon's agar. Of the otitis specimens, 63.7% showed typical Malassezia cells on cytological examination. In samples taken from the healthy ears of dogs with unilateral otitis, only 21.43% (P<0.05) showed evidence of Malassezia. M. pachydermatis was identified cytologically and culturally in 57.53% (P<0.05), 14.29% and 30.0% of samples from the ears of dogs with otitis, from the healthy ears of dogs with unilateral otitis and from the ears of healthy dogs with no otitis. In the group with otitis associated with M. pachydermatis, the poodle was the most common breed (39.29%; P<0.05), whereas in the group without otitis, the German Shepherd breed was prominent (although this observation was not statistically significant). In both groups, the majority of dogs with M. pachydermatis were aged between 1 and 3 years (P<0.05). The higher incidence of M. pachydermatis isolated from the ears of dogs with otitis externa suggests a putative pathogenic role of this yeast in this condition.


Asunto(s)
Dermatomicosis/veterinaria , Enfermedades de los Perros/microbiología , Malassezia/aislamiento & purificación , Otitis Externa/veterinaria , Animales , Dermatomicosis/microbiología , Perros , Femenino , Masculino , Otitis Externa/microbiología
20.
Zoonoses Public Health ; 63(6): 486-93, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26815766

RESUMEN

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.


Asunto(s)
Canidae , Rabia/veterinaria , Envejecimiento , Animales , Animales Salvajes , Reservorios de Enfermedades/veterinaria , Femenino , Masculino , Rabia/epidemiología , Rabia/virología , Vacunas Antirrábicas/inmunología , Virus de la Rabia , Estudios Retrospectivos , Zoonosis
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