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Josep Guarro - One of the best experts on this subject based on the ideXlab platform.
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Coelomycetous Fungi in the Clinical Setting: Morphological Convergence and Cryptic Diversity.
Journal of clinical microbiology, 2016Co-Authors: Nicomedes Valenzuela-lopez, Deanna A. Sutton, Nathan P. Wiederhold, Josep Guarro, José F. Cano-lira, Katihuska Paredes, Alberto M. StchigelAbstract:Human infections by coelomycetous fungi are becoming more frequent and range from superficial to systemic dissemination. Traumatic implantation of contaminated plant material is the most common cause. The typical morphological feature of these fungi is the production of asexual spores (conidia) within fruiting bodies called conidiomata. This study aimed to determine the distribution of the coelomycetes in clinical samples by a phenotypic and molecular study of a large set of isolates received from a U.S. reference mycological institution and by obtaining the in vitro antifungal susceptibility pattern of nine antifungals against a selected group of isolates. A total of 230 isolates were identified by sequencing the D1 and D2 domains of the large subunit (LSU) nuclear ribosomal RNA (nrRNA) gene and by morphological characterization. Eleven orders of the phylum Ascomycota were identified: Pleosporales (the largest group; 66.1%), Botryosphaeriales (19.57%), Glomerellales (4.35%), Diaporthales (3.48%), Xylariales (2.17%), Hysteriales and Valsariales (0.87%), and Capnodiales, Helotiales, Hypocreales and Magnaporthales (0.43% each). The most prevalent species were Neoscytalidium dimidiatum, Paraconiothyrium spp., Phoma herbarum, Didymella heteroderae, and Epicoccum sorghinum The most common anatomical site of isolation was superficial tissue (66.5%), followed by the respiratory tract (17.4%). Most of the isolates tested were susceptible to the majority of antifungals, and only flucytosine showed poor antifungal activity.
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Development of murine models of disseminated infection by Neoscytalidium dimidiatum
Medical mycology, 2010Co-Authors: Mery Ruíz-cendoya, Hugo Madrid, F. Javier Pastor, Emilio Mayayo, Marçal Mariné, Josep GuarroAbstract:We have developed two murine models of disseminated infections by Neoscytalidium dimidiatum, an emerging dematiaceous fungus. Immunosuppressed mice were challenged through the lateral tail vein with 1 x 10(5) or 1 x 10(6) CFU/ml and immunocompetent animals with 1 x 10(6) or 1 x 10(7) CFU/ml. N. dimidiatum var. dimidiatum was more virulent than the nonpigmented variety, N. dimidiatum var. hyalinum. All mice infected with N. dimidiatum var. dimidiatum died within 8 days while those infected with N. dimidiatum var. hyalinum survived to the end of the experiment. Fungal load in tissue was also higher in animals inoculated with N. dimidiatum var. dimidiatum. In general, of the five organs tested, spleens and kidneys were most affected.
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Evaluation of antifungal therapy in a neutropenic murine model of Neoscytalidium dimidiatum infection
International journal of antimicrobial agents, 2009Co-Authors: Mery Ruíz-cendoya, Hugo Madrid, Javier Pastor, Josep GuarroAbstract:We evaluated the efficacy of amphotericin B (1.5 mg/kg/day), voriconazole (60 mg/kg/day) and posaconazole (60 mg/kg/day) in a murine model of systemic infection caused by Neoscytalidium dimidiatum. All the treatments were able to prolong survival and to reduce the tissue burden in the spleen and kidneys of infected mice. Neither voriconazole nor posaconazole improved the results achieved with amphotericin B.
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Genotyping and in vitro antifungal susceptibility of Neoscytalidium dimidiatum isolates from different origins
International journal of antimicrobial agents, 2009Co-Authors: Hugo Madrid, Mery Ruíz-cendoya, Josep Cano, Alberto M. Stchigel, Rosane Orofino, Josep GuarroAbstract:This study evaluated the genetic variability and in vitro susceptibility patterns of isolates of Neoscytalidium dimidiatum and Scytalidium hyalinum from different geographical origins. Partial sequences of four loci (the ITS region and D1/D2 domains of the 28S rRNA gene and the tubulin and chitin synthase genes) were analysed. Among a total of 1970 bp sequenced in 24 isolates, 7 polymorphic positions (0.36%) were detected, representing five different sequence types (ST1-ST5), from which two (ST2 and ST3) were detected exclusively in isolates from plants, two (ST1 and ST5) were found only in clinical isolates and one (ST4) was observed in isolates from humans and from a mango tree. We propose subordinating S. hyalinum as a variety of N. dimidiatum. Amphotericin B was the most active drug, but low minimum inhibitory concentrations were also detected for voriconazole, terbinafine and anidulafungin.
Ana Cecilia Mesa-arango - One of the best experts on this subject based on the ideXlab platform.
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Onychomycosis caused by the environmental mold Neoscytalidium dimidiatum in Colombia, and in vitro antifungal susceptibility evaluation.
Medical mycology, 2020Co-Authors: Manuela Gil-gonzález, Juan C. Gómez-velásquez, Natalia Loaiza-díaz, Sindy V. Flórez-muñoz, Gilma Hernández-herrera, Ana Cecilia Mesa-arangoAbstract:Neoscytalidium dimidiatum is a plant pathogen, but can also cause onychomycosis. We compared clinical and epidemiological data of cases of onychomycosis caused by N. dimidiatum and Trichophyton rubrum. We also evaluated the in vitro antifungal susceptibility of N. dimidiatum clinical isolates. It was not possible to establish any statistical differences between groups, except the place of residence and the number of affected nails. The results suggest that onychomycosis caused by N. dimidiatum is clinically similar to that caused by T. rubrum; besides, N. dimidiatum has been shown to have low sensitivity to itraconazole, but high to terbinafine. LAY SUMMARY Cases of onychomycosis caused by Neoscytalidium dimidiatum were studied and compared to cases of onychomycosis caused by T. rubrum. The individuals affected were adults, and the clinical characteristics were not different between groups; accordingly, mycological diagnosis is mandatory.
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ITS rDNA Gene Analysis Versus MALDI-TOF MS For Identification of Neoscytalidium dimidiatum Isolated from Onychomycosis and Dermatomycosis Cases in Medellin (Colombia).
Microorganisms, 2019Co-Authors: Sindy V. Flórez-muñoz, Juan C. Gómez-velásquez, Natalia Loaiza-díaz, Célia Maria Gonçalves Soares, Carla Santos, Nelson Lima, Ana Cecilia Mesa-arangoAbstract:Within the Neoscytalidium genus, N. dimidiatum, N. oculus, N. orchidacearum, and N. novaehollandiae have been recognized. Although these species are frequently found in soil, N. dimidiatum has been identified as an etiologic agent of onychomycosis or dermatomycosis, and N. oculus has been identified as an etiologic agent of an ocular lesion. All these species can be cultured in vitro, but their morphological identification by macroscopic and microscopic traits is difficult and imprecise due to their similarity. In this study, 34 isolates of Neoscytalidium spp. from 32 onychomycosis and two dermatomycosis cases in Medellin (Colombia) were identified at the species level using sequencing of the ITS1+5.8S+ITS2 nuclear rDNA region and MALDI-TOF mass spectrometry (MS). Neoscytalidium dimidiatum strain MUM 17.21 was used to construct the reference spectrum in the in-house library to identify the clinical isolates by MALDI-TOF MS. Additionally, N. dimidiatum PPC-216 and PLAB-055 strains were used to validate the in-house constructed reference spectra. Although four groups were observed in the dendrogram obtained from the proteins of each isolate profile, MALDI-TOF MS and sequencing results are in accordance, since all isolates were identified as N. dimidiatum.
Themis J. Michailides - One of the best experts on this subject based on the ideXlab platform.
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Further Investigation on Limb Dieback of Fig (Ficus carica) Caused by Neoscytalidium dimidiatum in California.
Plant disease, 2020Co-Authors: Giorgio Gusella, David P. Morgan, Themis J. MichailidesAbstract:Fig limb dieback is a cosmopolitan disease caused by Neoscytalidium dimidiatum (Botryosphaeriaceae), characterized by branch and shoot cankers, discoloration of woody tissues, and dieback. The present study investigated the etiology of the disease in California that seems to have become prevalent among fig orchards in the last several years. During orchard surveys in Fresno, Kern, and Madera Counties over 3 years, we isolated consistently and evaluated the pathogenicity of N. dimidiatum under laboratory and field conditions. The effect of summer and winter pruning on the disease severity and the effects of different environmental and mechanical stresses, such as sunburn and wounding by mallets, were assayed. In addition, the susceptibility of six different cultivars and the effects of eradicating cankered shoots from the fig trees as a method to combat the spread of the disease were studied. Pathogenicity tests demonstrated that N. dimidiatum induces cankers on fig, mainly on wounded shoots. Results from the remaining experiments revealed that summer infection leads to more severe canker lesions than those induced by winter infection and that stressed shoots are more susceptible to infection than nonstressed shoots. 'Brown Turkey', 'Conadria', and 'Calimyrna' cultivars (all nonpersistent figs, i.e., needing pollination for fruit development) were less susceptible than the more susceptible 'Kadota', 'Sierra', and 'Black Mission' (all persistent figs, i.e., not needing pollination for fruit development). Canker removal from the orchard seems to be a good agronomic practice to avoid the spread of disease.
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further investigation on limb dieback of fig ficus carica caused by Neoscytalidium dimidiatum in california
Plant Disease, 2020Co-Authors: Giorgio Gusella, David P. Morgan, Themis J. MichailidesAbstract:Fig limb dieback is a cosmopolitan disease caused by Neoscytalidium dimidiatum (Botryosphaeriaceae), characterized by branch and shoot cankers, discoloration of woody tissues, and dieback. The present study investigated the etiology of the disease in California that seems to have become prevalent among fig orchards in the last several years. During orchard surveys in Fresno, Kern and Madera Counties for three years, we isolated consistently and evaluated the pathogenicity of N. dimidiatum under laboratory and field conditions. The effect of summer and winter pruning on the disease severity, and the effects of different environmental and mechanical stresses, such as sunburn and wounding by mallets used to harvest fruit, were assayed. In addition, the susceptibility of six different cultivars and the effect of eradication of cankered shoots from the fig trees as an effective method to combat the spread of the disease were also studied. Pathogenicity tests demonstrated that N. dimidiatum is able to induce cankers on fig, mainly on wounded shoots. Results from the remaining experiments reveal that summer infection leads to more severe canker lesions than those induced by winter infection, and that stressed shoots are more susceptible to infection than non-stressed shoots. Brown Turkey, Conadria and Calimyrna cultivars (all non-persistent figs, meaning requiring pollination for fruit development) were less susceptible compared to more susceptible Kadota, Sierra, and Black Mission (all persistent figs, i.e., non-requiring pollination for fruit development). Canker removal from the orchard seems to be a good agronomic practice to avoid the spread of pre-existing disease.
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Neoscytalidium dimidiatum Causing Canker, Shoot Blight and Fruit Rot of Almond in California.
Plant disease, 2018Co-Authors: M. T. Nouri, Daniel P. Lawrence, Mohammad A. Yaghmour, Themis J. Michailides, Florent P. TrouillasAbstract:Almond trees with trunk and branch cankers were observed in several orchards across almond-producing counties in California. Symptoms of cankers included bark lesions, discoloration of xylem tissues, longitudinal wood necrosis, and extensive gumming. Spur and shoot blight associated with rotted fruit were detected in two orchards in Kern County. The fungus Neoscytalidium dimidiatum was consistently recovered from the various cankers, infected fruit, and blighted shoots and its identity was confirmed based on phylogenetic and morphological studies. Phylogenetic analyses of the internal transcribed spacer, translation elongation factor 1-α, and β-tubulin genes comparing 47 strains from California with reference specimens within the family Botryosphaeriaceae and coupled with detailed morphological observations validated the identity of the pathogenic fungus. Pathogenicity tests conducted in the field using 1- to 2-year-old branches inoculated with mycelium plugs or conidial suspensions and attached fruit inoculated with conidial suspensions fulfilled Koch's postulates. N. dimidiatum appeared highly virulent in almond-producing cankers of up to 22 cm in length within 4 weeks using mycelium plug inoculations as well as severe fruit rot combined with spur blight on the fruit-bearing spurs. This study reports, for the first time, the fungus N. dimidiatum as a pathogen of almond in California causing canker, shoot blight, and fruit rot. Disease symptoms are described and illustrated.
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first report of lasiodiplodia citricola and Neoscytalidium dimidiatum causing death of graft union of english walnut in california
Plant Disease, 2013Co-Authors: Shuaifei Chen, David P. Morgan, Elizabeth J Fichtner, Themis J. MichailidesAbstract:California produces 99% of the English walnuts (Juglans regia) in the USA. In August 2012 in Tulare County, about 5,000 out of 90,000 trees were killed in a walnut nursery by a distinct black canker that developed around the graft union. The cankers appeared to be initiated at the heading cut on the rootstock, and expanded down to the rootstock and through the budded union up to the scion, resulting in mortality of scion. The walnut nursery was located adjacent to a mature walnut orchard. The fungi isolated from the cankers were identified as Lasiodiplodia citricola and Neoscytalidium dimidiatum based on morphological characteristics and DNA sequence comparisons. L. citricola was isolated from one of the 10 graft unions, while N. dimidiatum from the other nine. L. citricola isolates were characterized by white, aerial mycelium on potato dextrose agar that turned gray after 4 days and produced ellipsoidal to ovoid hyaline one-celled conidia that became 2-celled and brown with thick walls and longitudinal striations in the wall (1). N. dimidiatum isolates were characterized by ellipsoid to ovoid, hyaline conidia with a truncate base and an acutely rounded apex, initially 1-celled, and some becoming brown and 2-celled at maturity; no muriform conidia were produced (3). These identifications were confirmed by analyses of the ITS, BT2, and TEF-1α gene regions. The three gene regions were amplified by using the primers and methods described in (4). For L. citricola (isolates 7E78 to 7E80), a DNA sequence BLASTn at GenBank showed 100% identity with accessions GU945354 (ITS) and GU945340 (TEF-1α) of the ex-type specimen (CBS124707, BT2 sequencing data was not available) (3). For N. dimidiatum (isolates 7E61 to 7E63), a BLASTn search showed a high identify (ITS, 100%; BT2, 99%; TEF-1α, 99%) with reference sequence of N. dimidiatum (ITS, GQ330903; BT2, GU251768; TEF-1α, GU251240). Sequences of the studied DNA regions were deposited to GenBank as KC357298 to KC357303 (ITS); KC357304 to KC357309 (BT2); and, KC357310 to KC357315 (TEF-1α). The pathogenicity of L. citricola in comparison with N. dimidiatum in J. regia cvs. Chandler, Tulare, and Vina was evaluated in an orchard at KARE, by using two isolates each of L. citricola (7E78, 7E80) and N. dimidiatum (7E61, 7E63). Pathogenicity tests were performed by inoculating ten 2-year-old branches per isolate in late September 2012 by the method described in (2). After 3 weeks, the average lesion lengths caused by L. citricola on Chandler, Tulare, and Vina were 152, 156, and 188 mm, respectively, and 32, 38, and 34 mm, respectively, caused by N. dimidiatum. The lesion length averages produced on the three cultivars by the four isolates were all significantly (P < 0.05) longer than their respective controls (average length 10 mm on all cultivars). L. citricola, but not N. dimidiatum, killed branches of Chandler, Tulare, and Vina in 10 days. Both L. citricola and N. dimidiatum were reisolated from the inoculated branches and no fungus was isolated from the control, confirming Koch's postulates. These results confirmed that the walnut graft union canker was caused by either L. citricola or N. dimidiatum. To our knowledge, this is the first report of death of newly grafted walnut trees caused by L. citricola and N. dimidiatum worldwide, and also the first report of L. citricola infecting walnut worldwide. References: (1) J. Abdollahzadeh et al. Persoonia. 25:1, 2010. (2) S. F. Chen et al. Plant Dis. 97:994, 2013. (3) D. Pavlic et al. Mycologia. 106:851, 2008. (4) B. Slippers et al. Mycologia. 96:83, 2004.
Hugo Madrid - One of the best experts on this subject based on the ideXlab platform.
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Development of murine models of disseminated infection by Neoscytalidium dimidiatum
Medical mycology, 2010Co-Authors: Mery Ruíz-cendoya, Hugo Madrid, F. Javier Pastor, Emilio Mayayo, Marçal Mariné, Josep GuarroAbstract:We have developed two murine models of disseminated infections by Neoscytalidium dimidiatum, an emerging dematiaceous fungus. Immunosuppressed mice were challenged through the lateral tail vein with 1 x 10(5) or 1 x 10(6) CFU/ml and immunocompetent animals with 1 x 10(6) or 1 x 10(7) CFU/ml. N. dimidiatum var. dimidiatum was more virulent than the nonpigmented variety, N. dimidiatum var. hyalinum. All mice infected with N. dimidiatum var. dimidiatum died within 8 days while those infected with N. dimidiatum var. hyalinum survived to the end of the experiment. Fungal load in tissue was also higher in animals inoculated with N. dimidiatum var. dimidiatum. In general, of the five organs tested, spleens and kidneys were most affected.
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Evaluation of antifungal therapy in a neutropenic murine model of Neoscytalidium dimidiatum infection
International journal of antimicrobial agents, 2009Co-Authors: Mery Ruíz-cendoya, Hugo Madrid, Javier Pastor, Josep GuarroAbstract:We evaluated the efficacy of amphotericin B (1.5 mg/kg/day), voriconazole (60 mg/kg/day) and posaconazole (60 mg/kg/day) in a murine model of systemic infection caused by Neoscytalidium dimidiatum. All the treatments were able to prolong survival and to reduce the tissue burden in the spleen and kidneys of infected mice. Neither voriconazole nor posaconazole improved the results achieved with amphotericin B.
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Genotyping and in vitro antifungal susceptibility of Neoscytalidium dimidiatum isolates from different origins
International journal of antimicrobial agents, 2009Co-Authors: Hugo Madrid, Mery Ruíz-cendoya, Josep Cano, Alberto M. Stchigel, Rosane Orofino, Josep GuarroAbstract:This study evaluated the genetic variability and in vitro susceptibility patterns of isolates of Neoscytalidium dimidiatum and Scytalidium hyalinum from different geographical origins. Partial sequences of four loci (the ITS region and D1/D2 domains of the 28S rRNA gene and the tubulin and chitin synthase genes) were analysed. Among a total of 1970 bp sequenced in 24 isolates, 7 polymorphic positions (0.36%) were detected, representing five different sequence types (ST1-ST5), from which two (ST2 and ST3) were detected exclusively in isolates from plants, two (ST1 and ST5) were found only in clinical isolates and one (ST4) was observed in isolates from humans and from a mango tree. We propose subordinating S. hyalinum as a variety of N. dimidiatum. Amphotericin B was the most active drug, but low minimum inhibitory concentrations were also detected for voriconazole, terbinafine and anidulafungin.
Sindy V. Flórez-muñoz - One of the best experts on this subject based on the ideXlab platform.
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Onychomycosis caused by the environmental mold Neoscytalidium dimidiatum in Colombia, and in vitro antifungal susceptibility evaluation.
Medical mycology, 2020Co-Authors: Manuela Gil-gonzález, Juan C. Gómez-velásquez, Natalia Loaiza-díaz, Sindy V. Flórez-muñoz, Gilma Hernández-herrera, Ana Cecilia Mesa-arangoAbstract:Neoscytalidium dimidiatum is a plant pathogen, but can also cause onychomycosis. We compared clinical and epidemiological data of cases of onychomycosis caused by N. dimidiatum and Trichophyton rubrum. We also evaluated the in vitro antifungal susceptibility of N. dimidiatum clinical isolates. It was not possible to establish any statistical differences between groups, except the place of residence and the number of affected nails. The results suggest that onychomycosis caused by N. dimidiatum is clinically similar to that caused by T. rubrum; besides, N. dimidiatum has been shown to have low sensitivity to itraconazole, but high to terbinafine. LAY SUMMARY Cases of onychomycosis caused by Neoscytalidium dimidiatum were studied and compared to cases of onychomycosis caused by T. rubrum. The individuals affected were adults, and the clinical characteristics were not different between groups; accordingly, mycological diagnosis is mandatory.
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ITS rDNA Gene Analysis Versus MALDI-TOF MS For Identification of Neoscytalidium dimidiatum Isolated from Onychomycosis and Dermatomycosis Cases in Medellin (Colombia).
Microorganisms, 2019Co-Authors: Sindy V. Flórez-muñoz, Juan C. Gómez-velásquez, Natalia Loaiza-díaz, Célia Maria Gonçalves Soares, Carla Santos, Nelson Lima, Ana Cecilia Mesa-arangoAbstract:Within the Neoscytalidium genus, N. dimidiatum, N. oculus, N. orchidacearum, and N. novaehollandiae have been recognized. Although these species are frequently found in soil, N. dimidiatum has been identified as an etiologic agent of onychomycosis or dermatomycosis, and N. oculus has been identified as an etiologic agent of an ocular lesion. All these species can be cultured in vitro, but their morphological identification by macroscopic and microscopic traits is difficult and imprecise due to their similarity. In this study, 34 isolates of Neoscytalidium spp. from 32 onychomycosis and two dermatomycosis cases in Medellin (Colombia) were identified at the species level using sequencing of the ITS1+5.8S+ITS2 nuclear rDNA region and MALDI-TOF mass spectrometry (MS). Neoscytalidium dimidiatum strain MUM 17.21 was used to construct the reference spectrum in the in-house library to identify the clinical isolates by MALDI-TOF MS. Additionally, N. dimidiatum PPC-216 and PLAB-055 strains were used to validate the in-house constructed reference spectra. Although four groups were observed in the dendrogram obtained from the proteins of each isolate profile, MALDI-TOF MS and sequencing results are in accordance, since all isolates were identified as N. dimidiatum.