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Medicinas Complementárias
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1.
Invest Ophthalmol Vis Sci ; 62(6): 26, 2021 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-34038512

RESUMEN

Purpose: To investigate the antifungal and anti-inflammatory effects of baicalein on Aspergillus fumigatus (A. fumigatus) keratitis and the underlying mechanisms. Methods: The noncytotoxic antifungal concentration of baicalein was determined using CCK8, cell scratch assay, minimum inhibitory concentration, biofilm formation, scanning electron microscopy, propidium iodide uptake test and adherence assay in vitro and Draize test in vivo. In fungal keratitis (FK) mouse models, clinical score and plate count were used to evaluate FK severity, and myeloperoxidase assay and immunofluorescence staining were performed to examine neutrophil infiltration and activity. Real-time PCR, ELISA, and Western blot were performed to explore the anti-inflammatory activity of baicalein and the underlying mechanisms in vivo and in vitro. Results: Baicalein at 0.25 mM (noncytotoxic) significantly inhibited A. fumigatus growth, biofilm formation, and adhesion in vitro. In A. fumigatus keratitis mice, baicalein mitigated FK severity, reduced fungal load, and inhibited neutrophil infiltration and activity. Baicalein not only suppressed mRNA and protein levels of proinflammatory factors IL-1ß, IL-6, and TNF-α, but also inhibited the expression of thymic stromal lymphopoietin (TSLP) and TSLP receptor (TSLPR) in vivo and in vitro. In HCECs, mRNA and protein levels of IL-1ß, IL-6, and TNF-α were significantly lower in the TSLP siRNA-treated group, while higher in the rTSLP-treated group than in the corresponding control. Baicalein treatment significantly inhibited rTSLP induced the expression of IL-1ß, IL-6, and TNF-α. Conclusions: Baicalein plays a protective role in mouse A. fumigatus keratitis by inhibiting fungal growth, biofilm formation, and adhesion, and suppressing inflammatory response via downregulation of the TSLP/TSLPR pathway.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Citocinas/antagonistas & inhibidores , Infecciones Fúngicas del Ojo/tratamiento farmacológico , Flavanonas/uso terapéutico , Inflamación/tratamiento farmacológico , Queratitis/tratamiento farmacológico , Animales , Aspergilosis/metabolismo , Aspergilosis/microbiología , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/aislamiento & purificación , Aspergillus fumigatus/ultraestructura , Western Blotting , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Epitelio Corneal/efectos de los fármacos , Epitelio Corneal/metabolismo , Infecciones Fúngicas del Ojo/metabolismo , Infecciones Fúngicas del Ojo/microbiología , Femenino , Queratitis/metabolismo , Queratitis/microbiología , Ratones , Ratones Endogámicos C57BL , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Reacción en Cadena en Tiempo Real de la Polimerasa , Linfopoyetina del Estroma Tímico
2.
J Infect Dis ; 224(6): 1069-1076, 2021 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-33528496

RESUMEN

BACKGROUND: Cutaneous mold infections commonly result from an array of traumatic injuries that involve direct inoculation of contaminated soil into wounds. Here, we explored the use of antimicrobial blue light (aBL; 405 nm wavelength) and the combination of aBL with quinine hydrochloride (aBL + Q-HCL) for the treatment of cutaneous mold infections. METHODS: Efficacy of aBL and aBL + Q-HCL in killing clinically important pathogenic molds (Aspergillus fumigatus, Aspergillus flavus, and Fusarium oxyprorum) was investigated. Ultraperformance liquid chromatography identified and quantified endogenous porphyrins in the mold conidia. Finally, a mouse model of dermabrasion wound infected with a bioluminescent variant of A. fumigatus was developed to investigate the efficacy of aBL in treating cutaneous mold infections. RESULTS: We demonstrated that mold conidia are tolerant to aBL, but Q-HCL enhances efficacy. Transmission electron microscopy revealed intracellular damage by aBL. aBL + Q-HCL resulted in intracellular and cell wall damage. Porphyrins were observed in all mold strains, with A. fumigatus having the highest concentration. aBL and aBL + Q-HCL effectively reduced the burden of A. fumigatus within an established dermabrasion infection and limited recurrence posttreatment. CONCLUSIONS: aBL and aBL + Q-HCL may offer a novel approach for the treatment of mold infections.


Asunto(s)
Antibacterianos/uso terapéutico , Aspergillus fumigatus/aislamiento & purificación , Porfirinas , Quinina/uso terapéutico , Enfermedades Cutáneas Infecciosas/tratamiento farmacológico , Animales , Luz , Ratones , Enfermedades Cutáneas Infecciosas/diagnóstico , Esporas Fúngicas
3.
Mol Biol Rep ; 47(4): 2901-2911, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32239464

RESUMEN

An endophytic fungus Aspergillus fumigatus isolated from Moringa oleifera has been evaluated for its various bioactivities. The chloroformic fungal extract exhibited a good antimicrobial as well as antibiofilm activity against various pathogenic microorganisms. It also demonstrated a good antimutagenicity against the reactive carcinogenic ester generating mutagen, 2-aminofluorene (2-AF) with IC50 values of 0.52 mg ml-1 and 0.36 mg ml-1 in case of co-incubation and pre-incubation, respectively. The antiprolifertive activity against different cancer cell lines; such as HCT-15, HeLa A549 and U87-MG showed the IC50 values of 0.061, 0.065 and 0.072 mg ml-1, respectively. The antioxidant activity of fungal extract has been assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethyl-benzthiazolin-6-sulfonicacid) (ABTS) methods with IC50 values of 40.07 µg and 54.28 µg, respectively. Total phenolics and flavonoid contents have been also determined. Ultra-high performance liquid chromatography (UPLC) of fungal extract revealed the presence of various phenolic compounds (caffeic acid, rutin, ellagic acid, quercetin and kaempferol). Further an attempt has been made to purify the bioactive compounds by column chromatography and GC-MS analysis. The above studies demonstrated a good bioactive potential of endophytic fungus Aspergillus fumigatus and shows the pharmacological importance of an endophytic fungus and justify the need to carry out further studies.


Asunto(s)
Aspergillus fumigatus/aislamiento & purificación , Aspergillus fumigatus/metabolismo , Moringa oleifera/microbiología , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Antioxidantes/farmacología , Aspergillus fumigatus/fisiología , Biopelículas/efectos de los fármacos , Cromatografía Líquida de Alta Presión/métodos , Flavonoides/farmacología , Hongos/efectos de los fármacos , Moringa oleifera/metabolismo , Fenoles/farmacología , Extractos Vegetales/farmacología
4.
Mycoses ; 63(4): 376-381, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31981256

RESUMEN

BACKGROUND: Chronic pulmonary aspergillosis (CPA) is a progressive respiratory disease, caused most commonly by A fumigatus, with significant morbidity and mortality. Azole resistance in A fumigatus is a growing concern worldwide, with resistance to itraconazole reported in up to 50% of patients. AIM: The aim of this study was to determine whether a positive Aspergillus PCR (polymerase chain reaction) is a marker of resistance in CPA patients on azole therapy. METHODS: Patients were selected via a consecutive database search for the first 50 CPA patients with a positive Aspergillus PCR from January to September 2016. Data were collected regarding concurrent and subsequent culture results, current therapy and serum antifungal levels. PCR-positive patients not on therapy were included as the control group. RESULTS: Twenty-three patients were on therapy (15 itraconazole, 4 voriconazole and 4 posaconazole). Cycle threshold (Ct) values ranged from 20.8 to 37.9; no significant difference was found between each treatment and the control group (P = .47). In treated patients, concurrent azole-resistant A fumigatus was found in 75% of A fumigatus-positive cultures (6/8). All of the resistant isolates in the itraconazole group showed therapy resistance. Twenty per cent of all itraconazole levels were sub-therapeutic. No significant difference was found in serum itraconazole levels for patients on itraconazole with a positive PCR versus negative PCR (P = .44). CONCLUSION: Positive sputum, Aspergillus-specific PCR can be associated with azole resistance in CPA patients on therapy.


Asunto(s)
Aspergillus fumigatus/aislamiento & purificación , Azoles/uso terapéutico , Farmacorresistencia Fúngica , Aspergilosis Pulmonar/tratamiento farmacológico , Antifúngicos/uso terapéutico , Aspergillus/efectos de los fármacos , Aspergillus/genética , Aspergillus/aislamiento & purificación , Aspergillus fumigatus/efectos de los fármacos , Femenino , Proteínas Fúngicas/genética , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Estudios Retrospectivos
5.
Pharmacol Res Perspect ; 7(6): e00546, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31763045

RESUMEN

Rezafungin acetate is a novel echinocandin in clinical development for prevention and treatment of invasive fungal infections. Rezafungin is differentiated by a pharmacokinetic/pharmacodynamic (PK/PD) profile that includes a long half-life allowing once-weekly administration, front-loaded plasma drug exposures associated with antifungal efficacy, and penetration into deep-seated infections, such as intra-abdominal abscesses. In this series of in vivo studies, rezafungin demonstrated efficacy in the treatment of neutropenic mouse models of disseminated candidiasis, including infection caused by azole-resistant Candida albicans, and aspergillosis. These results contribute to a growing body of evidence demonstrating the antifungal efficacy and potential utility of rezafungin in the treatment of invasive fungal infections.


Asunto(s)
Antifúngicos/farmacocinética , Aspergilosis/tratamiento farmacológico , Candidiasis Invasiva/tratamiento farmacológico , Equinocandinas/farmacocinética , Administración Oral , Animales , Antifúngicos/administración & dosificación , Aspergilosis/inmunología , Aspergilosis/microbiología , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/aislamiento & purificación , Candida albicans/efectos de los fármacos , Candida albicans/aislamiento & purificación , Candidiasis Invasiva/sangre , Candidiasis Invasiva/inmunología , Candidiasis Invasiva/microbiología , Modelos Animales de Enfermedad , Esquema de Medicación , Equinocandinas/administración & dosificación , Femenino , Semivida , Humanos , Huésped Inmunocomprometido , Masculino , Ratones , Pruebas de Sensibilidad Microbiana , Neutropenia/inmunología
6.
Microbiology (Reading) ; 165(9): 967-975, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31309923

RESUMEN

Endophytes, a potential source of bioactive secondary metabolites, were isolated from the widely used medicinal plant Calotropis procera Ait. Approximately 675 segments from 15 Calotropis procera plants and 15 latex samples were assessed for the presence of endophytic fungi. Finally, eight fungal species were isolated and identified based on their macro- and micro-morphology. The endophytic fungal filtrates were screened for their antimicrobial activity against 11 important pathogenic micro-organisms. The filtrates of nanoparticles were from three of the eight isolated endophytic fungi, namely, Penicillium chrysogenum, Aspergillus fumigatus and Aspergillus flavus, and were highly effective against the tested bacteria, while the remaining endophytic fungal filtrates displayed low activity.


Asunto(s)
Antibacterianos/biosíntesis , Calotropis/microbiología , Endófitos/aislamiento & purificación , Hongos/aislamiento & purificación , Nanopartículas/microbiología , Aspergillus flavus/aislamiento & purificación , Aspergillus flavus/metabolismo , Aspergillus fumigatus/aislamiento & purificación , Aspergillus fumigatus/metabolismo , Endófitos/clasificación , Hongos/clasificación , Pruebas de Sensibilidad Microbiana/métodos , Penicillium chrysogenum/aislamiento & purificación , Penicillium chrysogenum/metabolismo
7.
Mycologia ; 111(2): 217-224, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30896313

RESUMEN

Aspergillus fumigatus resistant to azole as first-line therapy has been reported in azole-naïve patients. This worldwide resistance phenomenon has been linked to fungicide-driven alterations in the cyp51A gene and its promoter region (such as TR34/L98H and TR46/Y121F/T289A). Azole-resistant A. fumigatus related to the use of triazole fungicides in flower fields was recently reported In Colombia. The purpose of this study was to investigate the presence of azole-resistant A. fumigatus in soil samples from vegetable crops such as carrots, potatoes, maize, strawberries, and pea, and from prepared farming land surrounding the city of Bogotá. Species identification was based on sequencing of the ß-tubulin and calmodulin genes. All A. fumigatus strains were screened for azole resistance on agar supplemented with itraconazole or voriconazole. Among the 60 soil samples, 34 (56.6%) were positive for A. fumigatus and 15 samples exhibited strains (n = 18) that grew on agar supplemented with itraconazole or voriconazole. Triazole-resistant strains were isolated from soil samples associated with carrot, potato, maize, and pea crops. Sequencing of the cyp51A gene and its promoter region indicated polymorphism, mainly with the presence of TR46/Y121F/T289A (n = 8), TR34/L98H, and TR53. Eight resistant isolates exhibited cyp51A wild type without alterations in the promoter region. Our study showed evidence of dissemination of azole-resistant A. fumigatus, with high genetic diversity, in vegetable crops in Colombia. These data underline the need to determine the prevalence of azole resistance in A. fumigatus in clinical and environmental settings for other regions of Colombia as well as Latin America.


Asunto(s)
Aspergillus fumigatus/efectos de los fármacos , Azoles/administración & dosificación , Sistema Enzimático del Citocromo P-450/genética , Farmacorresistencia Fúngica , Proteínas Fúngicas/genética , Fungicidas Industriales/administración & dosificación , Enfermedades de las Plantas/prevención & control , Verduras/microbiología , Aspergillus fumigatus/clasificación , Aspergillus fumigatus/crecimiento & desarrollo , Aspergillus fumigatus/aislamiento & purificación , Azoles/farmacología , Calmodulina/genética , Colombia , Fungicidas Industriales/farmacología , Humanos , Polimorfismo Genético , Regiones Promotoras Genéticas , Análisis de Secuencia de ADN , Microbiología del Suelo , Tubulina (Proteína)/genética
8.
J Infect Chemother ; 25(4): 307-310, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30503017

RESUMEN

Aspergillus species are a major cause of life-threatening infections in immunocompromised hosts, and the most common pathogen of invasive aspergillosis is Aspergillus fumigatus. Recently, the development of molecular identification has revealed cryptic Aspergillus species, and A. felis is one such species within the Aspergillus section Fumigati reported in 2013. We describe a case of invasive pulmonary aspergillosis caused by A. felis in a 41-year-old Japanese woman diagnosed with myelodysplastic syndrome. She presented with fever 19 days after undergoing autologous peripheral blood stem cell transplantation and was clinically diagnosed with invasive pulmonary aspergillosis. Bronchoscopy and bronchoalveolar lavage were performed for definitive diagnosis. The ß-tubulin genes of the mold isolated from the bronchoalveolar lavage fluid, and sequenced directly from the PCR products using a primer pair were found to have 100% homology with A. felis. We successfully treated the patient with echinocandin following careful susceptibility testing. To the best of our knowledge, this is the first published case reporting the clinical course for diagnosis and successful treatment of invasive aspergillosis by A. felis.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergillus fumigatus/aislamiento & purificación , Huésped Inmunocomprometido/inmunología , Aspergilosis Pulmonar Invasiva/microbiología , Administración Intravenosa , Adulto , Antifúngicos/farmacología , Aspergillus fumigatus/efectos de los fármacos , Líquido del Lavado Bronquioalveolar/microbiología , Quimioterapia Combinada/métodos , Femenino , Humanos , Aspergilosis Pulmonar Invasiva/tratamiento farmacológico , Aspergilosis Pulmonar Invasiva/inmunología , Pruebas de Sensibilidad Microbiana , Síndromes Mielodisplásicos/inmunología , Síndromes Mielodisplásicos/terapia , Trasplante de Células Madre de Sangre Periférica/efectos adversos
9.
Artículo en Inglés | MEDLINE | ID: mdl-29914956

RESUMEN

A pan-azole-resistant Aspergillus fumigatus strain with the cyp51A mutations Gly138Ser and Asn248Lys was isolated from a patient receiving long-term voriconazole treatment. PCR fragments containing cyp51A with the mutations were introduced along with the Cas9 protein and single guide RNA into the azole-resistant/susceptible strains. Recombinant strains showed increased susceptibility via the replacement of Ser138 by glycine. Genetic recombination, which has been hampered thus far in clinical isolates, can now be achieved using CRISPR/Cas9 genome editing.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/genética , Sistema Enzimático del Citocromo P-450/genética , Farmacorresistencia Fúngica/genética , Proteínas Fúngicas/genética , Edición Génica/métodos , Voriconazol/uso terapéutico , Anciano , Aspergillus fumigatus/aislamiento & purificación , Sistemas CRISPR-Cas/genética , Humanos , Masculino
10.
Rev. otorrinolaringol. cir. cabeza cuello ; 78(1): 36-42, mar. 2018. tab, graf, ilus
Artículo en Español | LILACS | ID: biblio-902812

RESUMEN

RESUMEN Introducción: La otomicosis en pacientes inmunosuprimidos esta caracterizada por ser bilateral y ser causada por candida. Pocos estudios comparan las características micológicas encontradas en la microscopía directa y el cultivo. Objetivo: Identificar las características clínicas y micológicas de la otomicosis en pacientes diabéticos. Material y método: Estudio transversal en centro hospitalario de segundo nivel. Criterios de inclusión: pacientes diabéticos con diagnóstico clínico de otomicosis. Intervención: la muestra se examinó directamente bajo el microscopio y se cultivó. Resultados: Se incluyeron 17 pacientes, 10 mujeres y 7 hombres con una edad media de 47,5 años. Los síntomas predominantes fueron hipoacusia en 91,4% (n =16), prurito en 82,4% (n =14), otorrea en 76,5% (n=13)y otalgia en 70,6% (n =12). Afección bilateral se encontró en 47,1% (n =8). Estudio directo al microscopio mostró levaduras en 94,1% (n =16) y 5,9% mostró aspergillus (n =1). Cándida fue el género más comúnmente encontrado en los cultivos y en el examen directo microscópico con 94,1% (n =16) y Candida albicans la especie más común con 88,2% (n =15). Conclusión: Candida albicans es el agente etiológico más común en pacientes diabéticos con otomicosis. Su presentación clínica más frecuente es hipoacusia, prurito y otorrea. El examen directo identificó adecuadamente a los géneros fúngicos.


ABSTRACT Introduction: Otomycosis in immunocompromised patients is characterize by its bilateral course and the predominant etiologic agent is Candida. Few studies compare the mycological features between microscopic direct exam and culture. Aim: To identify the clinical and mycological characteristics of otomycosis in diabetic patients. Material and method: Transversal study. Secondary care center. Inclusion criteria: diabetic patients with clinical diagnosis of otomycosis. Intervention: Direct examination under a microscope of the ear sample and culture. Results: We included 17 patients, 10 women, 7 men with a mean age of 47.5 years. Symptoms were hearing loss 94.1% (n = 16), pruritus 82.4% (n =14) otorrhoea 76.5% (n =13) and otalgia 70.6% (n =12). Bilateral involvement was found in 47.1% (n =8). Direct microscopic study found 94.1% of yeast (n =16) and 5.9% of Aspergillus (n =1). Candida was the most common fungal genus in culture and microscopic exam with 94.1% (n =16) of cases and Candida albicans was the most common species in 88.2% (n =15) cases. Conclusion: Candida albicans is the most common etiologic agent in diabetic patients with otomycosis. Main symptoms were hearing loss, itching and otorrhea. Direct exam correctly identified the fungal genus.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Complicaciones de la Diabetes/microbiología , Otomicosis/microbiología , Aspergillus fumigatus/aislamiento & purificación , Estaciones del Año , Factores de Tiempo , Infecciones Oportunistas , Candida albicans/aislamiento & purificación , Evolución Clínica , Estudios Transversales , Candida glabrata/aislamiento & purificación , Complicaciones de la Diabetes/epidemiología , Otomicosis/epidemiología
11.
Environ Microbiol ; 20(1): 270-280, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29124846

RESUMEN

Emerging azole resistance in Aspergillus fumigatus poses a serious threat to human health. This nationwide surveillance study investigated the prevalence and molecular characteristics of azole-resistant A. fumigatus environmental isolates in Taiwan, an island country with increasing use of azole fungicides. Of the 2760 air and soil samples screened from 2014 to 2016, 451 A. fumigatus isolates were recovered from 266 samples and 34 isolates from 29 samples displayed resistance to medical azoles (itraconazole, voriconazole or posaconazole). The resistance prevalence was 10.9% and 7.5% in A. fumigatus-positive samples and isolates respectively. Most (29, 85.3%) azole-resistant isolates harboured TR34 /L98H mutations, which were widely distributed, clustered genetically with clinical isolates, and had growth rates that were similar to those of the wild-type isolates. Microsatellite genotyping revealed both the global spread of the TR34 /L98H isolates and the occurrence of TR34 /L98H/S297T/F495I isolates belonging to local microsatellite genotypes. AfuMDR3 and atrF, two efflux transporter genes, were constitutively upregulated in two individual resistant isolates without cyp51A mutations, highlighting their potential roles in azole resistance. These results emphasize the need for periodic environmental surveillance at the molecular level in regions in which azole fungicides are applied, and agricultural fungicide management strategies that generate less selective pressure should be investigated.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Aspergilosis/epidemiología , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/genética , Azoles/uso terapéutico , Farmacorresistencia Fúngica/genética , Microbiología del Aire , Aspergilosis/microbiología , Aspergillus fumigatus/aislamiento & purificación , Sistema Enzimático del Citocromo P-450/genética , Proteínas Fúngicas/genética , Genotipo , Humanos , Itraconazol/uso terapéutico , Pruebas de Sensibilidad Microbiana , Repeticiones de Microsatélite/genética , Mutación/genética , Prevalencia , Microbiología del Suelo , Taiwán/epidemiología , Triazoles/uso terapéutico , Voriconazol/uso terapéutico
12.
Artículo en Inglés | MEDLINE | ID: mdl-28893772

RESUMEN

Aspergillus fumigatus azole resistance has emerged as a global health problem. We evaluated the in vitro antifungal susceptibility of 221 clinical A. fumigatus isolates according to CLSI guidelines. Sixty-one isolates exhibiting MICs at the epidemiological cutoff value (ECV) for itraconazole or above the ECV for any triazole were checked for CYP51A mutations. No mutations were documented, even for the isolates (1.8%) with high voriconazole MICs, indicating that triazoles may be used safely to treat aspergillosis in Brazil.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Aspergillus fumigatus/efectos de los fármacos , Farmacorresistencia Fúngica/genética , Infecciones Fúngicas Invasoras/tratamiento farmacológico , Itraconazol/uso terapéutico , Voriconazol/uso terapéutico , Aspergillus fumigatus/aislamiento & purificación , Brasil , Humanos , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos
13.
J Antimicrob Chemother ; 71(8): 2075-8, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27494830

RESUMEN

Given reports showing a high prevalence of azole resistance in Aspergillus fumigatus, alternatives to azole therapy are discussed when a threshold of 10% of azole-resistant environmental isolates is reached. This raises the issue of calculation of this threshold, either on the prevalence of azole-resistant isolates as a whole or on the prevalence of azole-resistant cases in populations at risk of invasive aspergillosis (IA). For isolate evaluation, there are high disparities in routine microbiological procedures for the isolation of A. fumigatus and azole resistance detection. There are also huge differences between the microbiological work-up for diagnosing IA. Some centres rely on galactomannan detection alone without actively trying to culture appropriate samples, which affects reliability of the figures on the prevalence of resistance and thus the threshold of resistance. Moreover, reports from the laboratory could mix up figures from completely different patient populations: frequent azole-resistant isolates from pneumology patients and rare azole-resistant isolates from haematology patients. Therefore, to sum isolates from different specimens and different wards can lead to erroneous calculations for the restricted populations at risk of developing IA. In conclusion, assessing the incidence of azole resistance in A. fumigatus should be based on harmonized consensual microbiological methods and reports should be restricted to IA episodes in identified populations at risk of IA when the issue is to define an operational threshold for modifying recommendations.


Asunto(s)
Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/aislamiento & purificación , Azoles/farmacología , Farmacorresistencia Fúngica , Aspergilosis Pulmonar Invasiva/tratamiento farmacológico , Humanos , Incidencia , Aspergilosis Pulmonar Invasiva/diagnóstico , Aspergilosis Pulmonar Invasiva/microbiología , Pruebas de Sensibilidad Microbiana/métodos , Prevalencia
15.
Antimicrob Agents Chemother ; 60(1): 387-92, 2016 01.
Artículo en Inglés | MEDLINE | ID: mdl-26525787

RESUMEN

We employed an endpoint genotyping method to update the prevalence rate of positivity for the TR34/L98H mutation (a 34-bp tandem repeat mutation in the promoter region of the cyp51A gene in combination with a substitution at codon L98) and the TR46/Y121F/T289A mutation (a 46-bp tandem repeat mutation in the promoter region of the cyp51A gene in combination with substitutions at codons Y121 and T289) among clinical Aspergillus fumigatus isolates obtained from different regions of Iran over a recent 5-year period (2010 to 2014). The antifungal activities of itraconazole, voriconazole, and posaconazole against 172 clinical A. fumigatus isolates were investigated using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) broth microdilution method. For the isolates with an azole resistance phenotype, the cyp51A gene and its promoter were amplified and sequenced. In addition, using a LightCycler 480 real-time PCR system, a novel endpoint genotyping analysis method targeting single-nucleotide polymorphisms was evaluated to detect the L98H and Y121F mutations in the cyp51A gene of all isolates. Of the 172 A. fumigatus isolates tested, the MIC values of itraconazole (≥16 mg/liter) and voriconazole (>4 mg/liter) were high for 6 (3.5%). Quantitative analysis of single-nucleotide polymorphisms showed the TR34/L98H mutation in the cyp51A genes of six isolates. No isolates harboring the TR46/Y121F/T289A mutation were detected. DNA sequencing of the cyp51A gene confirmed the results of the novel endpoint genotyping method. By microsatellite typing, all of the azole-resistant isolates had genotypes different from those previously recovered from Iran and from the Dutch TR34/L98H controls. In conclusion, there was not a significant increase in the prevalence of azole-resistant A. fumigatus isolates harboring the TR34/L98H resistance mechanism among isolates recovered over a recent 5-year period (2010 to 2014) in Iran. A quantitative assay detecting a single-nucleotide polymorphism in the cyp51A gene of A. fumigatus is a reliable tool for the rapid screening and monitoring of TR34/L98H- and TR46/Y121F/T289A-positive isolates and can easily be incorporated into clinical mycology algorithms.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergillus fumigatus/genética , Sistema Enzimático del Citocromo P-450/genética , Farmacorresistencia Fúngica/genética , Proteínas Fúngicas/genética , Polimorfismo de Nucleótido Simple , Aspergilosis/tratamiento farmacológico , Aspergilosis/epidemiología , Aspergilosis/microbiología , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/enzimología , Aspergillus fumigatus/aislamiento & purificación , Sistema Enzimático del Citocromo P-450/metabolismo , ADN de Hongos/genética , Proteínas Fúngicas/metabolismo , Expresión Génica , Humanos , Irán/epidemiología , Itraconazol/uso terapéutico , Pruebas de Sensibilidad Microbiana , Repeticiones de Microsatélite , Técnicas de Tipificación Micológica , Regiones Promotoras Genéticas , Estudios Retrospectivos , Análisis de Secuencia de ADN , Triazoles/uso terapéutico , Voriconazol/uso terapéutico
17.
Int J Environ Res Public Health ; 12(6): 6319-32, 2015 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-26042369

RESUMEN

Fungal contamination in indoor environments has been associated with adverse health effects for the inhabitants. Remediation of fungal contamination requires removal of the fungi present and modifying the indoor environment to become less favourable to growth.  This may include treatment of indoor environments with an antifungal agent to prevent future growth. However there are limited published data or advice on chemical agents suitable for indoor fungal remediation. The aim of this study was to assess the relative efficacies of five commercially available cleaning agents with published or anecdotal use for indoor fungal remediation. The five agents included two common multi-purpose industrial disinfectants (Cavicide® and Virkon®), 70% ethanol, vinegar (4.0%-4.2% acetic acid), and a plant-derived compound (tea tree (Melaleuca alternifolia) oil) tested in both a liquid and vapour form. Tea tree oil has recently generated interest for its antimicrobial efficacy in clinical settings, but has not been widely employed for fungal remediation. Each antifungal agent was assessed for fungal growth inhibition using a disc diffusion method against a representative species from two common fungal genera, (Aspergillus fumigatus and Penicillium chrysogenum), which were isolated from air samples and are commonly found in indoor air. Tea tree oil demonstrated the greatest inhibitory effect on the growth of both fungi, applied in either a liquid or vapour form. Cavicide® and Virkon® demonstrated similar, although less, growth inhibition of both genera. Vinegar (4.0%-4.2% acetic acid) was found to only inhibit the growth of P. chrysogenum, while 70% ethanol was found to have no inhibitory effect on the growth of either fungi. There was a notable inhibition in sporulation, distinct from growth inhibition after exposure to tea tree oil, Virkon®, Cavicide® and vinegar. Results demonstrate that common cleaning and antifungal agents differ in their capacity to inhibit the growth of fungal genera found in the indoor air environment. The results indicate that tea tree oil was the most effective antifungal agent tested, and may have industrial application for the remediation of fungal contamination in residential and occupational buildings.


Asunto(s)
Contaminación del Aire Interior/prevención & control , Desinfectantes , Fungicidas Industriales , Aceite de Árbol de Té , Ácido Acético , Aspergillus fumigatus/aislamiento & purificación , Etanol , Hongos/aislamiento & purificación , Vivienda , Humanos , Pruebas de Sensibilidad Microbiana , Penicillium chrysogenum/aislamiento & purificación
18.
J Antimicrob Chemother ; 70(4): 1064-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25604745

RESUMEN

OBJECTIVES: The most common mechanism of azole (itraconazole and voriconazole) resistance in Aspergillus fumigatus is a mutation at the cyp51A locus. The aim of our study was to determine the rate of cyp51A mutations in lung transplant recipients (LTR) undergoing targeted antifungal prophylaxis with 12 weeks of voriconazole. METHODS: We conducted a prospective study that included 22 LTR with A. fumigatus between October 2008 and November 2011. Of those, 10 LTR were colonized with A. fumigatus and 12 had invasive pulmonary aspergillosis. RESULTS: Four patients were found to have A. fumigatus isolates with a cyp51A mutation, two had colonization and two had invasive pulmonary aspergillosis. The remaining 18 LTR had WT cyp51A A. fumigatus isolates. All A. fumigatus isolates (except one due to mixed growth) were tested for antifungal susceptibility. A total of nine LTR were exposed to azoles prior to A. fumigatus isolation for a median duration of 249 (IQR 99-524) days. Azole exposure preceded the isolation of two mutant isolates and seven WT isolates. None of the cyp51A mutant isolates conferred phenotypic resistance to azoles. CONCLUSIONS: Targeted antifungal prophylaxis in LTR did not lead to cyp51A resistance mutations in this cohort. Data on larger cohorts who receive universal antifungal prophylaxis are needed.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergillus fumigatus/enzimología , Sistema Enzimático del Citocromo P-450/genética , Proteínas Fúngicas/genética , Trasplante de Pulmón , Tasa de Mutación , Aspergilosis Pulmonar/microbiología , Voriconazol/uso terapéutico , Aspergillus fumigatus/genética , Aspergillus fumigatus/aislamiento & purificación , Quimioprevención/métodos , Humanos , Estudios Prospectivos , Receptores de Trasplantes
19.
Am J Ophthalmol ; 158(1): 64-70.e2, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24792103

RESUMEN

PURPOSE: To compare the in vitro effect of rose bengal and riboflavin as photosensitizing agents for photodynamic therapy (PDT) on fungal isolates that are common causes of fungal keratitis. DESIGN: Experimental study. METHODS: Three isolates (Fusarium solani, Aspergillus fumigatus, Candida albicans) recovered from patients with confirmed fungal keratitis were used in the experiments. Isolates were grown on Sabouraud-Dextrose agar, swabbed, and prepared in suspension, and 1 mL aliquots were inoculated onto test plates in triplicate. Test plates were separated into 5 groups: Group 1, no treatment; Group 2, 0.1% rose bengal alone; Group 3, 518 nm irradiation alone; Group 4, riboflavin PDT (riboflavin + 375 nm irradiation); and Group 5, rose bengal PDT (rose bengal + 518 nm irradiation). Irradiation was performed over a circular area using either a green light-emitting diode (LED) array (peak wavelength: 518 nm) or an ultraviolet-A LED array (peak wavelength: 375 nm). Test plates were irradiated with an energy density of 5.4 J/cm(2). Later, plates were placed in a 30 C incubator and observed for growth. RESULTS: Rose bengal-mediated PDT successfully inhibited the growth of all 3 fungal isolates in the irradiated area. All other groups exhibited unrestricted growth throughout the plate. CONCLUSIONS: Rose bengal-mediated PDT successfully inhibited the growth of 3 types of fungi. No other experimental groups, including riboflavin-mediated PDT, had any inhibitory effect on the isolates. The results might be useful for the treatment of patients suffering from corneal infection.


Asunto(s)
Úlcera de la Córnea/tratamiento farmacológico , Infecciones Fúngicas del Ojo/tratamiento farmacológico , Hongos/efectos de los fármacos , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Riboflavina/farmacología , Rosa Bengala/farmacología , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/aislamiento & purificación , Técnicas Bacteriológicas , Candida albicans/efectos de los fármacos , Candida albicans/aislamiento & purificación , Úlcera de la Córnea/microbiología , Infecciones Fúngicas del Ojo/microbiología , Hongos/aislamiento & purificación , Fusarium/efectos de los fármacos , Fusarium/aislamiento & purificación , Humanos , Luz , Pruebas de Sensibilidad Microbiana
20.
Curr Opin Infect Dis ; 26(6): 493-500, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24126719

RESUMEN

PURPOSE OF REVIEW: Reports from the end of the 2000s forced the medical community to take azole resistance in Aspergillus fumigatus into account. Not only patients with chronic aspergillus disease, who develop resistance during long-term azole treatment, but also azole-naive patients are at risk, owing to the presence of resistant strains in the environment. The purpose of this review is to overview the latest findings concerning the origin, evolution, and implications of azole resistance in A. fumigatus. RECENT FINDINGS: TR34/L98H is the predominant resistance mechanism of environmental origin in A. fumigatus. Recent epidemiological data show that this mechanism is an expanding problem, with reports from China, Iran, and India. However, the TR34/L98H strains from the Middle East are genotypically different from the European isolates; their emergence is, therefore, not due to simple geographical spread of the 'European' isolates. A new environmental resistance mechanism, TR46/Y121F/T289A, was detected in the Netherlands, conferring voriconazole resistance. In patients chronically treated with triazoles, the spectrum of resistance has become more diverse, with the emergence of non-CYP51A-mediated mechanisms. Central registration of treatment and outcome data of patients with resistant aspergillus disease are needed. SUMMARY: Azole resistance in A. fumigatus is evolving to a global health problem.


Asunto(s)
Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Aspergillus fumigatus/efectos de los fármacos , Azoles/uso terapéutico , Farmacorresistencia Fúngica Múltiple , Antifúngicos/farmacología , Aspergillus fumigatus/genética , Aspergillus fumigatus/aislamiento & purificación , Azoles/farmacología , Proteínas Fúngicas/genética , Humanos
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