In recent years the number of opportunistic invasive fusariosis has increased significantly, the main factors involved in these infections being reviewed here. In spite of the extensive literature ...published the advances in the management of disseminated fusariosis have been very poor and it remains a severe infection, refractory to treatment and with a high mortality rate. There are no ideal therapies and the presence of neutropenia has a critical part to play in the outcome of the infection. At least 70 species have been involved in fusariosis.
Fusarium solani
species complex is responsible for nearly 60 % of the cases and
F. oxysporum
species complex for approximately 20 % of them. Most of the infections are caused by four species, i.e.
F. petroliphilum, F. keratoplasticum
and other two unnamed phylogenetic species. The efficacy of amphotericin B and voriconazole, the most used antifungal drugs, for treating invasive fusariosis are controversial but in general the percentage of patients cured in the different clinical trials is low. Infections by
Fusarium verticillioides
seem to have the best prognosis. The recent release of complete genome sequences of the most clinically relevant species and the emergence of fungal genomics offer excellent opportunities for examining the multifactorial processes of
Fusarium
pathogenicity. Using knockout mutants of genes encoding sequence-specific proteins, several virulence factors have been characterized.
The genus Alternaria contains several species of melanized hyphomycetes that cause opportunistic human infections. The published literature contains 210 reported cases of human alternarioses between ...1933 and the present day. The most frequent clinical manifestations are cutaneous and subcutaneous infections (74.3%), followed by oculomycosis (9.5%), invasive and non-invasive rhinosinusitis (8.1%) and onychomycosis (8.1%). Immunosuppression is frequently associated with cutaneous and subcutaneous infections and rhinosinusitis. The most important risk factors for cutaneous and subcutaneous infections are solid organ transplantation and Cushing's syndrome, and those for rhinosinusitis are bone marrow transplants. Having been exposed to soil and garbage is common in all cases of oculomycosis, with corticotherapy being a risk factor in 50% of these cases. Previous contact with soil and/or trauma to the nails is associated with most cases of onychomycosis. In general, alternariosis shows a good response to conventional antifungal drugs. On some occasions, steroid suppression or reduction is sufficient to resolve an infection. Itraconazole is the antifungal drug used most frequently to successfully treat onychomycosis and cutaneous and subcutaneous infections. Posaconazole and voriconazole are promising therapeutic options, with the latter being especially so for oculomycosis.
The taxonomy of the coelomycetes has undergone dramatic changes in recent years, but remains controversial due to the high number of taxa involved, their poor morphological differentiation, the rare ...occurrence of the sexual morphs, and rapid loss of fertility in vitro. In the present study, we revisited the families Cucurbitariaceae and Didymellaceae (Pleosporales, Dothideomycetes), which include numerous plant pathogens, endophytic species associated with a wide host range, and saprobes. The taxonomy of two of the most relevant genera, i.e. Phoma and Pyrenochaeta, remains ambiguous after several phylogenetic studies, and needs further revision. We have studied a total of 143 strains of coelomycetes from clinical or environmental origin, by combining the LSU, ITS, tub2 and rpb2 sequences for a multi-locus analysis and a detailed morphological comparison. The resulting phylogenetic tree revealed that some fungi previously considered as members of Cucurbitariaceae represented five different families, and four of them, Neopyrenochaetaceae, Parapyrenochaetaceae, Pseudopyrenochaetaceae and Pyrenochaetopsidaceae, are proposed here as new. Furthermore, 13 new genera, 28 new species, and 20 new combinations are proposed within the Pleosporineae. Moreover, four new typifications are introduced to stabilise the taxonomy of these fungi.
Phylogeny of saprobic microfungi from Southern Europe Hernández-Restrepo, M.; Gené, J.; Castañeda-Ruiz, R.F. ...
Studies in mycology,
March 2017, 20170301, 2017-Mar, 2017-03-00, Letnik:
86, Številka:
1
Journal Article
Recenzirano
Odprti dostop
During a survey of saprophytic microfungi on decomposing woody, herbaceous debris and soil from different regions in Southern Europe, a wide range of interesting species of asexual ascomycetes were ...found. Phylogenetic analyses based on partial gene sequences of SSU, LSU and ITS proved that most of these fungi were related to Sordariomycetes and Dothideomycetes and to lesser extent to Leotiomycetes and Eurotiomycetes. Four new monotypic orders with their respective families are proposed here, i.e. Lauriomycetales, Lauriomycetaceae; Parasympodiellales, Parasympodiellaceae; Vermiculariopsiellales, Vermiculariopsiellaceae and Xenospadicoidales, Xenospadicoidaceae. One new order and three families are introduced here to accommodate orphan taxa, viz. Kirschsteiniotheliales, Castanediellaceae, Leptodontidiaceae and Pleomonodictydaceae. Furthermore, Bloxamiaceae is validated. Based on morphology and phylogenetic affinities Diplococcium singulare, Trichocladium opacum and Spadicoides atra are moved to the new genera Paradiplococcium, Pleotrichocladium and Xenospadicoides, respectively. Helicoon fuscosporum is accommodated in the genus Magnohelicospora. Other novel genera include Neoascotaiwania with the type species N. terrestris sp. nov., and N. limnetica comb. nov. previously accommodated in Ascotaiwania; Pleomonodictys with P. descalsii sp. nov. as type species, and P. capensis comb. nov. previously accommodated in Monodictys; Anapleurothecium typified by A. botulisporum sp. nov., a fungus morphologically similar to Pleurothecium but phylogenetically distant; Fuscosclera typified by F. lignicola sp. nov., a meristematic fungus related to Leotiomycetes; Pseudodiplococcium typified by P. ibericum sp. nov. to accommodate an isolate previously identified as Diplococcium pulneyense; Xyladictyochaeta typified with X. lusitanica sp. nov., a foliicolous fungus related to Xylariales and similar to Dictyochaeta, but distinguished by polyphialidic conidiogenous cells produced on setiform conidiophores. Other novel species proposed are Brachysporiella navarrica, Catenulostroma lignicola, Cirrenalia iberica, Conioscypha pleiomorpha, Leptodontidium aureum, Pirozynskiella laurisilvatica, Parasympodiella lauri and Zanclospora iberica. To fix the application of some fungal names, lectotypes and/or epitypes are designated for Magnohelicospora iberica, Sporidesmium trigonellum, Sporidesmium opacum, Sporidesmium asperum, Camposporium aquaticum and Psilonia atra.
Pathology to vertebrate hosts has emerged repeatedly in the order Ophiostomatales. Occasional infections have been observed in Sporothrix mexicana at a low level of virulence, while the main ...pathogenic species cluster in a derived clade around S. schenckii s.str.
In this paper, phylogeny and epidemiology of the members of this clade were investigated for 99 clinical and 36 environmental strains using four genetic loci, viz. rDNA ITS and partial CAL, TEF1, and TEF3; data are compared with amplified fragment length polymorphism (AFLP)
genotyping. The four main species of the pathogenic clade were recognised. The species proved to show high degrees of endemicity, which enabled interpretation of literature data where live material or genetic information is lacking. The clade of four species comprised nine subclusters, which
often had limited geographic distribution and were separate from each other in all partitions, suggesting low degrees of interbreeding between populations. In contrast, S. globosa exhibited consistent global distribution of identical AFLP types, suggesting another type of dispersal.
Sporothrix brasiliensis is known to be involved in an expanding zoonosis and transmitted by cats, whereas S. globosa infections originated from putrid plant material, causing a sapronosis. Sporothrix schenckii s.str., the most variable species within the clade, also had
a plant origin, with ecological similarities to that of S. globosa. A hypothesis was put forward that highly specific conditions in the plant material are required to promote the growth of Sporothrix. Fermented, self-heated plant debris may stimulate the thermodependent yeast-like
invasive form of the fungus, which facilitates repeated infection of mammals.
Clinical breakpoints (CBPs) have not been established for the Mucorales and any antifungal agent. In lieu of CBPs, epidemiologic cutoff values (ECVs) are proposed for amphotericin B, posaconazole, ...and itraconazole and four Mucorales species. Wild-type (WT) MIC distributions (organisms in a species-drug combination with no detectable acquired resistance mechanisms) were defined with available pooled CLSI MICs from 14 laboratories (Argentina, Australia, Canada, Europe, India, Mexico, and the United States) as follows: 10 Apophysomyces variabilis, 32 Cunninghamella bertholletiae, 136 Lichtheimia corymbifera, 10 Mucor indicus, 123 M. circinelloides, 19 M. ramosissimus, 349 Rhizopus arrhizus, 146 R. microsporus, 33 Rhizomucor pusillus, and 36 Syncephalastrum racemosum isolates. CLSI broth microdilution MICs were aggregated for the analyses. ECVs comprising ≥95% and ≥97.5% of the modeled populations were as follows: amphotericin B ECVs for L. corymbifera were 1 and 2 μg/ml, those for M. circinelloides were 1 and 2 μg/ml, those for R. arrhizus were 2 and 4 μg/ml, and those for R. microsporus were 2 and 2 μg/ml, respectively; posaconazole ECVs for L. corymbifera were 1 and 2, those for M. circinelloides were 4 and 4, those for R. arrhizus were 1 and 2, and those for R. microsporus were 1 and 2, respectively; both itraconazole ECVs for R. arrhizus were 2 μg/ml. ECVs may aid in detecting emerging resistance or isolates with reduced susceptibility (non-WT MICs) to the agents evaluated.
Mycoleptodiscus includes plant pathogens, animal opportunists, saprobic and endophytic fungi. The present study presents the first molecular phylogeny and revision of the genus based on four loci, ...including ITS, LSU, rpb2, and tef1. An extensive collection of Mycoleptodiscus
cultures, including ex-type strains from the CBS, IMI, MUCL, BRIP, clinical isolates from the USA, and fresh isolates from Brazil and Spain, was studied morphologically and phylogenetically to resolve their taxonomy. The study showed that Mycoleptodiscus sensu lato is polyphyletic.
Phylogenetic analysis places Mycoleptodiscus in Muyocopronales (Dothideomycetes), together with Arxiella, Leptodiscella, Muyocopron, Neocochlearomyces, and Paramycoleptodiscus. Mycoleptodiscus terrestris, the type species, and
M. sphaericus are reduced to synonyms, and one new species is introduced, M. suttonii. Mycoleptodiscus atromaculans, M. coloratus, M. freycinetiae, M. geniculatus, M. indicus, M. lateralis (including M. unilateralis and M. variabilis
as its synonyms) and M. taiwanensis belong to Muyocopron (Muyocopronales, Dothideomycetes), and M. affinis, and M. lunatus to Omnidemptus (Magnaporthales, Sordariomycetes). Based on phylogenetic analyses we propose Muyocopron
alcornii sp. nov., a fungus associated with leaf spots on Epidendrum sp. (Orchidaceae) in Australia, Muyocopron zamiae sp. nov. associated with leaf spots on Zamia (Zamiaceae) in the USA, and Omnidemptus graminis sp. nov. isolated from a grass
(Poaceae) in Spain. Furthermore, Neomycoleptodiscus venezuelense gen. & sp. nov. is introduced for a genus similar to Mycoleptodiscus in Muyocopronaceae.
The fungus Paecilomyces lilacinus is an emerging pathogen that causes severe human infections, including devastating oculomycosis. Usually, it shows low susceptibility to conventional antifungal ...drugs in vitro, and variable susceptibility to novel triazoles. A review of the published literature identified 119 reported cases of human infection by P. lilacinus between 1964 and 2004. Most were cases of oculomycosis (51.3%), followed by cutaneous and sub-cutaneous infections (35.3%), and a smaller group of miscellaneous infections (13.4%). Lens implantation is the most frequent predisposing factor for oculomycosis. Cutaneous and sub-cutaneous infections occur mainly in solid organ and bone marrow transplant recipients, although surgery and primary or acquired immunodeficiency are also relevant predisposing factors. Infections in apparently immunocompetent patients have also been reported. Surgical debridement combined with antifungal drug therapy, or the correction of predisposing factors, such as neutropenia, are usually required to obtain improvement. Treatment with traditional antifungal drugs often fails. Voriconazole has demonstrated good activity in both cutaneous and ocular infections in the few cases in which this drug has been used. The new triazoles ravuconazole and posaconazole show good in-vitro activity against P. lilacinus and could be promising therapeutic alternatives.
Over 200 new sequences are generated for members of the genus Acremonium and related taxa including ribosomal small subunit sequences (SSU) for phylogenetic analysis and large subunit (LSU) sequences ...for phylogeny and DNA-based identification. Phylogenetic analysis reveals that within the Hypocreales, there are two major clusters containing multiple Acremonium species. One clade contains Acremonium sclerotigenum, the genus Emericellopsis, and the genus Geosmithia as prominent elements. The second clade contains the genera Gliomastix sensu stricto and Bionectria. In addition, there are numerous smaller clades plus two multi-species clades, one containing Acremonium strictum and the type species of the genus Sarocladium, and, as seen in the combined SSU/LSU analysis, one associated subclade containing Acremonium breve and related species plus Acremonium curvulum and related species. This sequence information allows the revision of three genera. Gliomastix is revived for five species, G. murorum, G. polychroma, G. tumulicola, G. roseogrisea, and G. masseei. Sarocladium is extended to include all members of the phylogenetically distinct A. strictum clade including the medically important A. kiliense and the protective maize endophyte A. zeae. Also included in Sarocladium are members of the phylogenetically delimited Acremonium bacillisporum clade, closely linked to the A. strictum clade. The genus Trichothecium is revised following the principles of unitary nomenclature based on the oldest valid anamorph or teleomorph name, and new combinations are made in Trichothecium for the tightly interrelated Acremonium crotocinigenum, Spicellum roseum, and teleomorph Leucosphaerina indica. Outside the Hypocreales, numerous Acremonium-like species fall into the Plectosphaerellaceae, and A. atrogriseum falls into the Cephalothecaceae.
Cladosporium is mainly known as a ubiquitous environmental saprobic fungus or plant endophyte, and to date, just a few species have been documented as etiologic agents in vertebrate hosts, including ...humans. In the present study, 10 new species of the genus were isolated from
human and animal clinical specimens from the USA. They are proposed and characterized on the basis of their morphology and a molecular phylogenetic analysis using DNA sequences from three loci (the ITS region of the rDNA, and partial fragments of the translation elongation factor 1-alpha and
actin genes). Six of those species belong to the C. cladosporioides species complex, i.e., C. alboflavescens, C. angulosum, C. anthropophilum, C. crousii, C. flavovirens and C. xantochromaticum, three new species belong to the C. herbarum
species complex, i.e., C. floccosum, C. subcinereum and C. tuberosum; and one to the C. sphaerospermum species complex, namely, C. succulentum. Differential morphological features of the new taxa are provided together with molecular barcodes to distinguish
them from the currently accepted species of the genus.
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