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Cienfuegos Alayo, Jhoselin Mariset - One of the best experts on this subject based on the ideXlab platform.
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Presencia de Malassezia Pachydermatis en Canis familiaris diagnosticados clínicamente con otitis externa en el distrito de Nuevo Chimbote, región Ancash - Perú 2016
Universidad Privada Antenor Orrego - UPAO, 2017Co-Authors: Cienfuegos Alayo, Jhoselin MarisetAbstract:La otitis canina externa es una inflamación del conducto auditivo externo, que se caracteriza por eritema, aumento de la descarga o descamación del epitelio, acompañado de dolor y/o irritación; entre uno de los agentes responsables de esta afección se tiene a Malassezia Pachydermatis. El presente trabajo de estudio, se realizó para determinar la presencia de Malassezia Pachydermatis en Canis familiaris, diagnosticados clínicamente con otitis externa, en el distrito de Nuevo Chimbote, región Ancash - Perú - 2016. Se utilizaron 53 Canis familiraris, como material biológico, los cuales fueron de diferente raza, edad, sexo. Se empleó como medio de diagnóstico, la citología por extendido directo, demostrándose la presencia de la levadura en un 74% (N=39/53) en Canis familiaris con otitis externa y en un 26% (N=14/53) de otitis canina externa debido a otras causas.External canine otitis is an inflammation of the external auditory canal, characterized by erythema, increased discharge or scaling of the epithelium, accompanied by pain and / or irritation; One of the agents responsible for this condition has Malassezia Pachydermatis. The present study was carried out to determine the presence of Malassezia Pachydermatis in Canis familiaris, clinically diagnosed with otitis externa, in the district of Nuevo Chimbote, Ancash region - Peru - 2016. We used 53 Canis familiraris, as biological material, which Were of different race, age, sex. Direct cytology was used as a diagnostic medium, with the presence of yeast in 74% (N = 39/53) in Canis familiaris with external otitis and 26% (N = 14/53) of otitis Canine due to other causes.Tesi
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Presencia de Malassezia Pachydermatis en canis familiaris diagnosticados clinicamente con otitis externa en el distrito de nuevo chimbote, región ancash - peru 2016
'Universidad Privada Antenor Orrego', 2017Co-Authors: Cienfuegos Alayo, Jhoselin MarisetAbstract:External canine otitis is an inflammation of the external auditory canal, characterized by erythema, increased discharge or scaling of the epithelium, accompanied by pain and / or irritation; One of the agents responsible for this condition has Malassezia Pachydermatis. The present study was carried out to determine the presence of Malassezia Pachydermatis in Canis familiaris, clinically diagnosed with otitis externa, in the district of Nuevo Chimbote, Ancash region - Peru - 2016. We used 53 Canis familiraris, as biological material, which Were of different race, age, sex. Direct cytology was used as a diagnostic medium, with the presence of yeast in 74% (N = 39/53) in Canis familiaris with external otitis and 26% (N = 14/53) of otitis Canine due to other causes.La otitis canina externa es una inflamación del conducto auditivo externo, que se caracteriza por eritema, aumento de la descarga o descamación del epitelio, acompañado de dolor y/o irritación; entre uno de los agentes responsables de esta afección se tiene a Malassezia Pachydermatis. El presente trabajo de estudio, se realizó para determinar la presencia de Malassezia Pachydermatis en Canis familiaris, diagnosticados clínicamente con otitis externa, en el distrito de Nuevo Chimbote, región Ancash - Perú - 2016. Se utilizaron 53 Canis familiraris, como material biológico, los cuales fueron de diferente raza, edad, sexo. Se empleó como medio de diagnóstico, la citología por extendido directo, demostrándose la presencia de la levadura en un 74% (N=39/53) en Canis familiaris con otitis externa y en un 26% (N=14/53) de otitis canina externa debido a otras causas
Domenico Otranto - One of the best experts on this subject based on the ideXlab platform.
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The role of drug efflux pumps in Malassezia Pachydermatis and Malassezia furfur defence against azoles
Mycoses, 2016Co-Authors: Roberta Iatta, Davide Immediato, Maria Rita Puttilli, Domenico Otranto, Claudia CafarchiaAbstract:Summary This study aims to evaluate the effect of efflux pump modulators (EPMs) on the minimal inhibitory concentration (MIC) of fluconazole (FLZ) and voriconazole (VOR) in Malassezia furfur and Malassezia Pachydermatis. The in vitro efficacy of azoles, in combination with EPMs (ie haloperidol-HAL, promethazine-PTZ and cyclosporine A-CYS), against 21 M. furfur from bloodstream infection patients and 14 M. Pachydermatis from the skin of dogs with dermatitis, was assessed using a broth microdilution chequerboard analysis. Data were analysed using the model-fractional inhibitory concentration index (FICI) method. The MIC of FLZ and VOR of Malassezia spp. decreased in the presence of sub-inhibitory concentrations of HAL and/or PTZ. The synergic effect was observed only in strains with FLZ MIC≥128 μg/mL for M. furfur, FLZ MIC≥64 μg/mL for M. Pachydermatis and VOR MIC≥4 μg/mL in both Malassezia spp. These results suggest that the drug efflux pumps are involved as defence mechanisms to azole drugs in Malassezia yeast. The synergism might be related to an increased expression of efflux pump genes, eventually resulting in azole resistance phenomena. Finally, the above FLZ and VOR MIC values might be considered the cut-off to discriminate susceptible and resistant strains.
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azole susceptibility of Malassezia Pachydermatis and Malassezia furfur and tentative epidemiological cut off values
Medical Mycology, 2015Co-Authors: Claudia Cafarchia, Roberta Iatta, Davide Immediato, Maria Rita Puttilli, Domenico OtrantoAbstract:: This study aims to determine the minimal inhibitory concentration (MIC) distribution and the epidemiological cut-off values (ECVs) of Malassezia Pachydermatis and Malassezia furfur isolates for fluconazole (FLZ), itraconazole (ITZ), posaconazole (POS), and voriconazole (VOR). A total of 62 M. Pachydermatis strains from dogs with dermatitis and 78 M. furfur strains from humans with bloodstream infections (BSI) were tested by a modified broth microdilution Clinical and Laboratory Standards Institute (CLSI) method. ITZ and POS displayed lower MICs than VOR and FLZ, regardless of the Malassezia species. The MIC data for azoles of M. Pachydermatis were four two-fold dilutions lower than those of M. furfur. Based on the ECVs, about 94% of Malassezia strains might be categorized within susceptible population for all azoles, except for FLZ, and azole cross-resistance was detected in association with FLZ in M. Pachydermatis but not in M. furfur.The study proposes, for the first time, tentative azole ECVs for M. Pachydermatis and M. furfur for monitoring the emergence of isolates with decreased susceptibilities and shows that the azole MIC distribution varied according to the Malassezia species tested, thus suggesting the usefulness of determining the susceptibility profile for effective treatment of each species.
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antifungal susceptibility of Malassezia Pachydermatis biofilm
Medical Mycology, 2013Co-Authors: Luciana Aguiar Figueredo, Claudia Cafarchia, Domenico OtrantoAbstract:Antifungal resistance has been associated with biofi lm formation in many microorganisms, but not yet in Malassezia Pachydermatis . This saprophytic yeast can cause otitis and dermatitis in dogs and has emerged as an important human pathogen, responsible for systemic infections in neonates in intensive care units. This study aims to evaluate the in vitro antifungal susceptibility of M. Pachydermatis strains, in both their planktonic and sessile forms, to fl uconazole, miconazole, ketoconazole, itraconazole, posaconazole, terbinafi ne and voriconazole using the XTT assay and Clinical and Laboratory Standards Institute (CLSI) microdilution method. The minimum inhibitory concentration (MIC) values recorded for each drug were signifi cantly higher for sessile cells relative to planktonic cells to the extent that 90% of M. Pachydermatis strains in their sessile form were classifi ed as resistant to all antifungal agents tested. Data suggest that M. Pachydermatis biofi lm formation is associated with antifungal resistance, paving the way towards investigating drug resistance mechanisms in Malassezia spp.
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in vitro antifungal susceptibility of Malassezia Pachydermatis from dogs with and without skin lesions
Veterinary Microbiology, 2012Co-Authors: Claudia Cafarchia, Roberta Iatta, Luciana Aguiar Figueredo, Maria Teresa Montagna, Domenico OtrantoAbstract:Abstract Canine Malassezia dermatitis is frequently treated with systemic ketoconazole (KTZ) and itraconazole (ITZ). However, no information is available on the antifungal susceptibility to azoles and allilamine of Malassezia Pachydermatis isolates from dogs with or without skin lesions. The present study was designed to evaluate the in vitro antifungal susceptibility of M. Pachydermatis strains from dogs with or without skin lesions to KTZ, ITZ, miconazole (MICO), fluconazole (FLZ), posaconazole (POS), voriconazole (VOR) and terbinafine (TER) using the Clinical and Laboratory Standards Institute reference Broth Microdilution Method (CLSI M27-A2). The association between the susceptibility to antifungal compounds and the origin of M. Pachydermatis , from skin with or without lesions has been also assessed. A total of 62 M. Pachydermatis strains from healthy dogs (i.e., Group A = 30) or with skin lesions (i.e., Group B = 32) were tested. ITZ, KTZ and POS showed the highest activity against M. Pachydermatis strains, whereas MICO TER and FLZ the lowest. A higher number of Malassezia resistant strains were registered among isolates from Group B than those from Group A. This study indicates that M. Pachydermatis strains were susceptible to ITZ, KTZ, and POS. However, dogs with lesions may harbour strains with low susceptibility to antifungal agents and displaying cross-resistance phenomena to azole. The antifungal therapy in Malassezia infections requires careful appraisal of choice of drugs especially in cases of unresponsiveness to antifungal treatment or recurrent infections.
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genetic variability and phospholipase production of Malassezia Pachydermatis isolated from dogs with diverse grades of skin lesions
Medical Mycology, 2010Co-Authors: Mauro Luis Da Silva Machado, Claudia Cafarchia, Domenico Otranto, Rafael Rodrigues Ferreira, Simone Passos Bianchi, Maria Stefania Latrofa, Antonio Parisi, Laerte FerreiroAbstract:Little detailed information is available on the association of Malassezia Pachydermatis genotypes and the extent of skin damage that they cause. In the present study, isolates of M. Pachydermatis, recovered from the skin of healthy dogs and dogs with dermatitis in Brazil, were characterized on the basis of partial sequencing of the large subunit (LSU), first internal transcribed spacer (ITS-1) and chitin synthase 2 gene (chs-2). The determination of phospholipase production was also included in the investigations. The severity of lesions and hyperpigmentation of dogs with skin disease were evaluated. For each locus, two main sequence types were designated as genotypes A and C. Two other minor sequence types (A2I–C2I) were also recorded and defined for the ITS-1. Genotype A isolates were the most prevalent, being recovered from healthy and diseased animals. No significant difference was detected among genotypes or ITS-1 sequence types and grades of skin damage or hyperpigmentation in the dogs with skin les...
Claudia Cafarchia - One of the best experts on this subject based on the ideXlab platform.
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The role of drug efflux pumps in Malassezia Pachydermatis and Malassezia furfur defence against azoles
Mycoses, 2016Co-Authors: Roberta Iatta, Davide Immediato, Maria Rita Puttilli, Domenico Otranto, Claudia CafarchiaAbstract:Summary This study aims to evaluate the effect of efflux pump modulators (EPMs) on the minimal inhibitory concentration (MIC) of fluconazole (FLZ) and voriconazole (VOR) in Malassezia furfur and Malassezia Pachydermatis. The in vitro efficacy of azoles, in combination with EPMs (ie haloperidol-HAL, promethazine-PTZ and cyclosporine A-CYS), against 21 M. furfur from bloodstream infection patients and 14 M. Pachydermatis from the skin of dogs with dermatitis, was assessed using a broth microdilution chequerboard analysis. Data were analysed using the model-fractional inhibitory concentration index (FICI) method. The MIC of FLZ and VOR of Malassezia spp. decreased in the presence of sub-inhibitory concentrations of HAL and/or PTZ. The synergic effect was observed only in strains with FLZ MIC≥128 μg/mL for M. furfur, FLZ MIC≥64 μg/mL for M. Pachydermatis and VOR MIC≥4 μg/mL in both Malassezia spp. These results suggest that the drug efflux pumps are involved as defence mechanisms to azole drugs in Malassezia yeast. The synergism might be related to an increased expression of efflux pump genes, eventually resulting in azole resistance phenomena. Finally, the above FLZ and VOR MIC values might be considered the cut-off to discriminate susceptible and resistant strains.
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azole susceptibility of Malassezia Pachydermatis and Malassezia furfur and tentative epidemiological cut off values
Medical Mycology, 2015Co-Authors: Claudia Cafarchia, Roberta Iatta, Davide Immediato, Maria Rita Puttilli, Domenico OtrantoAbstract:: This study aims to determine the minimal inhibitory concentration (MIC) distribution and the epidemiological cut-off values (ECVs) of Malassezia Pachydermatis and Malassezia furfur isolates for fluconazole (FLZ), itraconazole (ITZ), posaconazole (POS), and voriconazole (VOR). A total of 62 M. Pachydermatis strains from dogs with dermatitis and 78 M. furfur strains from humans with bloodstream infections (BSI) were tested by a modified broth microdilution Clinical and Laboratory Standards Institute (CLSI) method. ITZ and POS displayed lower MICs than VOR and FLZ, regardless of the Malassezia species. The MIC data for azoles of M. Pachydermatis were four two-fold dilutions lower than those of M. furfur. Based on the ECVs, about 94% of Malassezia strains might be categorized within susceptible population for all azoles, except for FLZ, and azole cross-resistance was detected in association with FLZ in M. Pachydermatis but not in M. furfur.The study proposes, for the first time, tentative azole ECVs for M. Pachydermatis and M. furfur for monitoring the emergence of isolates with decreased susceptibilities and shows that the azole MIC distribution varied according to the Malassezia species tested, thus suggesting the usefulness of determining the susceptibility profile for effective treatment of each species.
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antifungal susceptibility of Malassezia Pachydermatis biofilm
Medical Mycology, 2013Co-Authors: Luciana Aguiar Figueredo, Claudia Cafarchia, Domenico OtrantoAbstract:Antifungal resistance has been associated with biofi lm formation in many microorganisms, but not yet in Malassezia Pachydermatis . This saprophytic yeast can cause otitis and dermatitis in dogs and has emerged as an important human pathogen, responsible for systemic infections in neonates in intensive care units. This study aims to evaluate the in vitro antifungal susceptibility of M. Pachydermatis strains, in both their planktonic and sessile forms, to fl uconazole, miconazole, ketoconazole, itraconazole, posaconazole, terbinafi ne and voriconazole using the XTT assay and Clinical and Laboratory Standards Institute (CLSI) microdilution method. The minimum inhibitory concentration (MIC) values recorded for each drug were signifi cantly higher for sessile cells relative to planktonic cells to the extent that 90% of M. Pachydermatis strains in their sessile form were classifi ed as resistant to all antifungal agents tested. Data suggest that M. Pachydermatis biofi lm formation is associated with antifungal resistance, paving the way towards investigating drug resistance mechanisms in Malassezia spp.
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in vitro antifungal susceptibility of Malassezia Pachydermatis from dogs with and without skin lesions
Veterinary Microbiology, 2012Co-Authors: Claudia Cafarchia, Roberta Iatta, Luciana Aguiar Figueredo, Maria Teresa Montagna, Domenico OtrantoAbstract:Abstract Canine Malassezia dermatitis is frequently treated with systemic ketoconazole (KTZ) and itraconazole (ITZ). However, no information is available on the antifungal susceptibility to azoles and allilamine of Malassezia Pachydermatis isolates from dogs with or without skin lesions. The present study was designed to evaluate the in vitro antifungal susceptibility of M. Pachydermatis strains from dogs with or without skin lesions to KTZ, ITZ, miconazole (MICO), fluconazole (FLZ), posaconazole (POS), voriconazole (VOR) and terbinafine (TER) using the Clinical and Laboratory Standards Institute reference Broth Microdilution Method (CLSI M27-A2). The association between the susceptibility to antifungal compounds and the origin of M. Pachydermatis , from skin with or without lesions has been also assessed. A total of 62 M. Pachydermatis strains from healthy dogs (i.e., Group A = 30) or with skin lesions (i.e., Group B = 32) were tested. ITZ, KTZ and POS showed the highest activity against M. Pachydermatis strains, whereas MICO TER and FLZ the lowest. A higher number of Malassezia resistant strains were registered among isolates from Group B than those from Group A. This study indicates that M. Pachydermatis strains were susceptible to ITZ, KTZ, and POS. However, dogs with lesions may harbour strains with low susceptibility to antifungal agents and displaying cross-resistance phenomena to azole. The antifungal therapy in Malassezia infections requires careful appraisal of choice of drugs especially in cases of unresponsiveness to antifungal treatment or recurrent infections.
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genetic variability and phospholipase production of Malassezia Pachydermatis isolated from dogs with diverse grades of skin lesions
Medical Mycology, 2010Co-Authors: Mauro Luis Da Silva Machado, Claudia Cafarchia, Domenico Otranto, Rafael Rodrigues Ferreira, Simone Passos Bianchi, Maria Stefania Latrofa, Antonio Parisi, Laerte FerreiroAbstract:Little detailed information is available on the association of Malassezia Pachydermatis genotypes and the extent of skin damage that they cause. In the present study, isolates of M. Pachydermatis, recovered from the skin of healthy dogs and dogs with dermatitis in Brazil, were characterized on the basis of partial sequencing of the large subunit (LSU), first internal transcribed spacer (ITS-1) and chitin synthase 2 gene (chs-2). The determination of phospholipase production was also included in the investigations. The severity of lesions and hyperpigmentation of dogs with skin disease were evaluated. For each locus, two main sequence types were designated as genotypes A and C. Two other minor sequence types (A2I–C2I) were also recorded and defined for the ITS-1. Genotype A isolates were the most prevalent, being recovered from healthy and diseased animals. No significant difference was detected among genotypes or ITS-1 sequence types and grades of skin damage or hyperpigmentation in the dogs with skin les...
Rui Kano - One of the best experts on this subject based on the ideXlab platform.
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miconazole tolerant strains of Malassezia Pachydermatis generated by culture in medium containing miconazole
Veterinary Dermatology, 2020Co-Authors: Rui Kano, Hiroshi KamataAbstract:BACKGROUND: Tolerance of Malassezia Pachydermatis to azole drugs has been reported worldwide, from strains isolated from dogs. Canine Malassezia dermatitis often is treated with shampoos containing 2% miconazole (MCZ) or other topical MCZ products. OBJECTIVES: In the in vitro study herein, it was investigated whether MCZ‐induced amino acid substitutions in the lanosterol 14‐alpha‐demethylase (ERG11) gene 1 lead to azole tolerance in M. Pachydermatis. METHODS AND MATERIALS: Toleranced to MCZ was induced in an azole‐susceptible strain of M. Pachydermatis (CBS1879ᵀ) by culture in medium containing MCZ. Antifungal susceptibility to MCZ, clotrimazole (CTZ) and itraconazole (ITZ) was assessed using the modified broth microdilution (BM) method. To assess the potential mechanism of tolerance in the three MCZ‐resistant strains, ERG11 was sequenced. The interaction between the calcineurin inhibitor tacrolimus and MCZ in the azole‐tolerant isolates also was examined. RESULTS: Three strains (NUBS19001 to NUBS19003) from CBS1879ᵀ cultured in medium containing MCZ exhibited minimum inhibitory concentrations (MICs) of 40 mg/L to MCZ, 5 mg/L to ITZ and >32 mg/L to CTZ, meaning that the isolates were tolerant. The combination of MCZ and tacrolimus exerted an indifferent effect against the MCZ‐tolerant strain. BLAST analysis using the NCBI database showed mutations in the cytochrome p450 encoded by ERG11 in the MCZ‐tolerant strains. CONCLUSIONS: In the present in vitro study, it was shown that MCZ exposure can induce amino acid substitutions in ERG11 and subsequent tolerance of M. Pachydermatis to several azoles. Whether topical therapy with azole‐containing products can exert a similar effect in vivo is a question that requires further research.
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high multi azole resistant Malassezia Pachydermatis clinical isolates from canine Malassezia dermatitis
Medical Mycology, 2019Co-Authors: Rui Kano, Chizu Aramaki, Nobuo Murayama, Yuko Mori, Kentaro Yamagishi, Shinichi Yokoi, Hiroshi KamataAbstract:Malassezia Pachydermatis, a lipophilic and aerobic yeast, is a causative agent of Malassezia dermatitis, a common skin mycosis in dogs and cats. This fungus is also responsible for zoonotic fungal infections in human neonates. Ravuconazole (RVZ) is an antifungal azole compound and the active metabolite of fosravuconazole, which was approved for use in humans in Japan in 2018. In the present study, in vitro RVZ susceptibility and multi-azole resistance of 13 clinical M. Pachydermatis strains was investigated using the modified Clinical and Laboratory Standards Institute M27-A3 test. The minimum inhibitory concentrations (MICs) for the 13 isolates ranged from 0.094 to >32 mg/L for itraconazole (ITZ) and from 0.5 to >32 mg/l for RVZ. Similarly, MICs for ITZ- or RVZ-resistant strains (MICs >32 mg/l) were also >32 mg/l for clotrimazole (CTZ), >32 mg/l for miconazole (MCZ), and 0.25 to >32 mg/L for voriconazole (VRZ). BLAST analysis using the NCBI database showed that ERG11 cDNA of the RVZ-resistant strain encoded Gly at codon 461 and Asp in cytochrome p450 encoded by M. Pachydermatis ERG11 mRNA. This work is the first report to describe that an RVZ-resistant M. Pachydermatis strain contains ERG11 mutations. The affinity of the protein encoded by ERG11 for RVZ may differ from that of ITZ. Therefore, RVZ has considerable therapeutic potential for treating ITZ-resistant canine Malassezia dermatitis. However, RVZ-resistant strains already exist in canine Malassezia dermatitis in Japan.
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in vitro susceptibility of Malassezia Pachydermatis isolates from canine skin with atopic dermatitis to ketoconazole and itraconazole in east asia
Journal of Veterinary Medical Science, 2014Co-Authors: Shion Watanabe, Rui Kano, Masahiko Nagata, Atsuhiko Hasegawa, Cheolyong Hwang, Anna Koike, Charles Chen, Hiroshi KamataAbstract:Topical or oral azole antifungals are commonly used in canine atopic dermatitis (AD), as the lipophilic yeast Malassezia Pachydermatis exacerbates canine AD. To examine whether canine AD lesions harbor azole-resistant M. Pachydermatis isolates in East Asia, we investigated the in vitro susceptibility of M. Pachydermatis isolates to ketoconazole (KTZ) and itraconazole (ITZ) obtained from AD lesions of canines in Japan, Korea and Taiwan. The minimum inhibitory concentrations (MICs) of KTZ and ITZ were measured by the E-test using Sabouraud dextrose agar with 0.5% Tween 40. The MICs of KTZ and ITZ for isolates from canines with AD were significantly higher than the MICs for isolates from healthy canines. Our findings suggested that the clinical isolates from canine AD skin lesions were less susceptible to azoles than those from normal canine skin in East Asia.
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genotyping of Malassezia Pachydermatis isolates from canine healthy skin and lesional skin of atopic dermatitis in japan korea and taiwan
Journal of Veterinary Medical Science, 2013Co-Authors: Anna Koike, Rui Kano, Masahiko Nagata, Atsuhiko Hasegawa, Cheolyong Hwang, Charles Chen, Hiroshi KamataAbstract:Isolates of the yeast Malassezia Pachydermatis obtained from skin samples of healthy dogs and of dogs with atopic dermatitis in Japan, Taiwan and Korea were molecularly characterized using intergenic pacer 1 (IGS1) region analysis. The percentage of IGS1 subtype isolates detected in healthy skin was as follows: 1A (6%), 1B (27%), 1C (11%), 2A (6%), 2B (6%), 3A (11%), 3B (6%), 3C (3%) and 3D (24%). In contrast, the most prevalent isolates detected in skin lesions of atopic dermatitis were subtype 3D in Japan and Taiwan and subtype 3C in Korea. All subtype isolates grew well on acidic medium (pH 6). However, subtype 3C and 3D isolates grew better than the other subtype isolates on medium at pH 8.
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genotyping of Malassezia Pachydermatis isolates from canine healthy skin and atopic dermatitis by internal spacer 1 igs1 region analysis
Veterinary Dermatology, 2011Co-Authors: Tetsuya Kobayashi, Rui Kano, Masahiko Nagata, Atsuhiko Hasegawa, Hiroshi KamataAbstract:Isolates of Malassezia Pachydermatis from healthy dog skin and from dogs with atopic dermatitis were molecularly characterized using internal spacer 1 (IGS1) region analyses, and their phospholipase A2 activity and pH growth profiles were then characterized in vitro. The percentage of isolates from healthy dogs that had the following IGS1 subtypes (isotype, %) were as follows: 1A, 6%; 1B, 27%; 1C, 11%; 2A, 6%; 2B, 6%; 3A, 11%; 3C, 3%; and 3D, 24%. In contrast, 9% of isolates from dogs with atopic dermatitis were isotype IB and 91% were isotype 3D, indicating that isolates of subtype 3D were the most prevalent in dogs with atopic dermatitis. Production of phospholipase A2 was statistically higher in isolates of subtype 3D than in the other subtypes. The subtype 3D isolates showed enhanced growth on alkaline medium compared with non-3D subtype isolates. The main clinical sign of canine Malassezia dermatitis is waxy exudates on the skin, which predispose the patient to development of a yeast overgrowth of the subtype 3D. Increased phospholipase A2 production may be involved in the inflammatory process associated with Malassezia dermatitis.
Atsuhiko Hasegawa - One of the best experts on this subject based on the ideXlab platform.
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in vitro susceptibility of Malassezia Pachydermatis isolates from canine skin with atopic dermatitis to ketoconazole and itraconazole in east asia
Journal of Veterinary Medical Science, 2014Co-Authors: Shion Watanabe, Rui Kano, Masahiko Nagata, Atsuhiko Hasegawa, Cheolyong Hwang, Anna Koike, Charles Chen, Hiroshi KamataAbstract:Topical or oral azole antifungals are commonly used in canine atopic dermatitis (AD), as the lipophilic yeast Malassezia Pachydermatis exacerbates canine AD. To examine whether canine AD lesions harbor azole-resistant M. Pachydermatis isolates in East Asia, we investigated the in vitro susceptibility of M. Pachydermatis isolates to ketoconazole (KTZ) and itraconazole (ITZ) obtained from AD lesions of canines in Japan, Korea and Taiwan. The minimum inhibitory concentrations (MICs) of KTZ and ITZ were measured by the E-test using Sabouraud dextrose agar with 0.5% Tween 40. The MICs of KTZ and ITZ for isolates from canines with AD were significantly higher than the MICs for isolates from healthy canines. Our findings suggested that the clinical isolates from canine AD skin lesions were less susceptible to azoles than those from normal canine skin in East Asia.
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genotyping of Malassezia Pachydermatis isolates from canine healthy skin and lesional skin of atopic dermatitis in japan korea and taiwan
Journal of Veterinary Medical Science, 2013Co-Authors: Anna Koike, Rui Kano, Masahiko Nagata, Atsuhiko Hasegawa, Cheolyong Hwang, Charles Chen, Hiroshi KamataAbstract:Isolates of the yeast Malassezia Pachydermatis obtained from skin samples of healthy dogs and of dogs with atopic dermatitis in Japan, Taiwan and Korea were molecularly characterized using intergenic pacer 1 (IGS1) region analysis. The percentage of IGS1 subtype isolates detected in healthy skin was as follows: 1A (6%), 1B (27%), 1C (11%), 2A (6%), 2B (6%), 3A (11%), 3B (6%), 3C (3%) and 3D (24%). In contrast, the most prevalent isolates detected in skin lesions of atopic dermatitis were subtype 3D in Japan and Taiwan and subtype 3C in Korea. All subtype isolates grew well on acidic medium (pH 6). However, subtype 3C and 3D isolates grew better than the other subtype isolates on medium at pH 8.
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genotyping of Malassezia Pachydermatis isolates from canine healthy skin and atopic dermatitis by internal spacer 1 igs1 region analysis
Veterinary Dermatology, 2011Co-Authors: Tetsuya Kobayashi, Rui Kano, Masahiko Nagata, Atsuhiko Hasegawa, Hiroshi KamataAbstract:Isolates of Malassezia Pachydermatis from healthy dog skin and from dogs with atopic dermatitis were molecularly characterized using internal spacer 1 (IGS1) region analyses, and their phospholipase A2 activity and pH growth profiles were then characterized in vitro. The percentage of isolates from healthy dogs that had the following IGS1 subtypes (isotype, %) were as follows: 1A, 6%; 1B, 27%; 1C, 11%; 2A, 6%; 2B, 6%; 3A, 11%; 3C, 3%; and 3D, 24%. In contrast, 9% of isolates from dogs with atopic dermatitis were isotype IB and 91% were isotype 3D, indicating that isolates of subtype 3D were the most prevalent in dogs with atopic dermatitis. Production of phospholipase A2 was statistically higher in isolates of subtype 3D than in the other subtypes. The subtype 3D isolates showed enhanced growth on alkaline medium compared with non-3D subtype isolates. The main clinical sign of canine Malassezia dermatitis is waxy exudates on the skin, which predispose the patient to development of a yeast overgrowth of the subtype 3D. Increased phospholipase A2 production may be involved in the inflammatory process associated with Malassezia dermatitis.
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the genetic diversity of clinical isolates of Malassezia Pachydermatis from dogs and cats
Medical Mycology, 2001Co-Authors: Tomohiro Aizawa, Rui Kano, Yuka Nakamura, Shinichi Watanabe, Atsuhiko HasegawaAbstract:Molecular investigation of 110 clinical isolates of non-lipid-dependent Malassezia Pachydermatis from dogs and cats was carried out by random amplification of polymorphic DNA (RAPD) and chitin synthase 2 (CHS2) gene sequence analyses. The RAPD analysis indicated that the clinical isolates of M. Pachydermatis constituted four distinct genetic types (A, B, C and D). Moreover, the results from CHS2 gene analysis completely agreed with those from the RAPD analyses. The clinical isolates of M. Pachydermatis were obtained from normal external ears, lesions of atopic dermatitis, flea allergic dermatitis, otitis externa, pyoderma and seborrheic dermatitidis in dogs and cats. Type A consisted of 93 clinical isolates as well as the ex-neotype strain of M. Pachydermatis. The isolates of type A M. Pachydermatis originated from lesions of all kinds of diseases. They were predominant on dog and cat skin. The other types, B, C, and D were isolated mainly from otitis externa.
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molecular heterogeneity in clinical isolates of Malassezia Pachydermatis from dogs
Veterinary Microbiology, 1999Co-Authors: Tomohiro Aizawa, Rui Kano, Yuka Nakamura, Shinichi Watanabe, Atsuhiko HasegawaAbstract:Molecular investigation of 16 strains, conventionally identified to be Malassezia Pachydermatis, isolated from dogs in Japan was carried out by random amplification of polymorphic DNA (RAPD) and chitin synthase 2 (CHS2) gene sequence analyses. The RAPD band patterns of 13 clinical isolates were identical to that of standard strain of M. Pachydermatis (CBS-1879). The other three clinical isolates were different from the standard strain of M. Pachydermatis in RAPD patterns, and two of the three isolates were identical. About 620 bp genomic DNA fragments of the CHS2 gene were amplified from the same 16 clinical isolates of M. Pachydermatis by polymerase chain reaction (PCR) and sequenced. The phylogenetic analysis of the nucleotide sequences of CHS2 gene fragments of the 16 clinical isolates revealed that the 13 strains were genetically very close to the standard strain of M. Pachydermatis and the other two isolates were genetically close to the standard strain of M. furfur rather than M. Pachydermatis. The remaining one isolate was phylogenetically distinct from all the seven Malassezia species reported so far.