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1.
PLoS Pathog ; 16(1): e1008201, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31945142

RESUMO

Fungal pathogens represent a major human threat affecting more than a billion people worldwide. Invasive infections are on the rise, which is of considerable concern because they are accompanied by an escalation of antifungal resistance. Deciphering the mechanisms underlying virulence traits and drug resistance strongly relies on genetic manipulation techniques such as generating mutant strains carrying specific mutations, or gene deletions. However, these processes have often been time-consuming and cumbersome in fungi due to a number of complications, depending on the species (e.g., diploid genomes, lack of a sexual cycle, low efficiency of transformation and/or homologous recombination, lack of cloning vectors, nonconventional codon usage, and paucity of dominant selectable markers). These issues are increasingly being addressed by applying clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 mediated genetic manipulation to medically relevant fungi. Here, we summarize the state of the art of CRISPR-Cas9 applications in four major human fungal pathogen lineages: Candida spp., Cryptococcus neoformans, Aspergillus fumigatus, and Mucorales. We highlight the different ways in which CRISPR has been customized to address the critical issues in different species, including different strategies to deliver the CRISPR-Cas9 elements, their transient or permanent expression, use of codon-optimized CAS9, and methods of marker recycling and scarless editing. Some approaches facilitate a more efficient use of homology-directed repair in fungi in which nonhomologous end joining is more commonly used to repair double-strand breaks (DSBs). Moreover, we highlight the most promising future perspectives, including gene drives, programmable base editors, and nonediting applications, some of which are currently available only in model fungi but may be adapted for future applications in pathogenic species. Finally, this review discusses how the further evolution of CRISPR technology will allow mycologists to tackle the multifaceted issue of fungal pathogenesis.


Assuntos
Sistemas CRISPR-Cas , Micologia/métodos , Aspergillus fumigatus/genética , Cryptococcus neoformans/genética , Previsões , Edição de Genes , Humanos , Mucorales/genética
2.
PLoS One ; 14(10): e0217667, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31647810

RESUMO

Rice false smut, caused by the ascomycete Ustilaginoidea virens, is a serious disease of rice worldwide. Conidia are very important infectious propagules of U. virens, but the ability of pathogenic isolates to produce conidia frequently decreases in culture, which influences pathogenicity testing. Here, we developed tissue media with rice leaves or panicles that stimulate conidiation of U. virens. Among the tested media, 0.10 g/ml panicle medium was most efficient for conidiation. Whereas, some rice leaf media more effectively increased conidiation than panicle media except 0.10 g/ml panicle medium, and certain non-filtered tissue media were better than their filtered counterparts. Although the conidia induced in rice tissue media were smaller, they were able to germinate on potato sucrose agar medium and infect rice normally. The rice tissue medium is also workable in inducing conidia for conidiation-defective isolates. This method provides a foundation for the production of conidia by U. virens that will be widely applicable in pathogenicity testing as well as in genetic analyses for false smut resistance in rice cultivars.


Assuntos
Hypocreales/fisiologia , Oryza/microbiologia , Doenças das Plantas/microbiologia , Esporos Fúngicos/crescimento & desenvolvimento , Meios de Cultura/química , Meios de Cultura/farmacologia , Resistência à Doença/genética , Interações Hospedeiro-Patógeno , Inflorescência/química , Inflorescência/microbiologia , Micologia/métodos , Oryza/química , Oryza/genética , Doenças das Plantas/genética , Folhas de Planta/química , Folhas de Planta/microbiologia , Esporos Fúngicos/efeitos dos fármacos
4.
Genome Biol Evol ; 11(10): 2807-2817, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31529025

RESUMO

Podospora anserina is a model ascomycetous fungus which shows pronounced phenotypic senescence when grown on solid medium but possesses unlimited lifespan under submerged cultivation. In order to study the genetic aspects of adaptation of P. anserina to submerged cultivation, we initiated a long-term evolution experiment. In the course of the first 4 years of the experiment, 125 single-nucleotide substitutions and 23 short indels were fixed in eight independently evolving populations. Six proteins that affect fungal growth and development evolved in more than one population; in particular, in the G-protein alpha subunit FadA, new alleles fixed in seven out of eight experimental populations, and these fixations affected just four amino acid sites, which is an unprecedented level of parallelism in experimental evolution. Parallel evolution at the level of genes and pathways, an excess of nonsense and missense substitutions, and an elevated conservation of proteins and their sites where the changes occurred suggest that many of the observed fixations were adaptive and driven by positive selection.


Assuntos
Evolução Molecular , Podospora/genética , Alelos , Proteínas Fúngicas/genética , Variação Genética , Genoma Fúngico , Mutação INDEL , Micologia/métodos , Fenótipo , Podospora/crescimento & desenvolvimento
5.
Hautarzt ; 70(8): 558-560, 2019 08.
Artigo em Alemão | MEDLINE | ID: mdl-31384967
6.
BMC Infect Dis ; 19(1): 707, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399065

RESUMO

BACKGROUND: Talaromyces marneffei is a thermally dimorphic fungus endemic in south-east Asia. It predominantly occurs in both immunocompromised and immunosuppressed patients and can be fatal if diagnosis and treatment are delayed. The clinical manifestations of T. marneffei infection are nonspecific and rapid diagnosis of T. marneffei infection remains challenging. CASE PRESENTATION: A 24-year-old man came to our outpatient department with the sign of common skin lesions. The lesions were cuticolor follicular papules with or without central umbilication, nodules and acne-like lesions, which are common in syringoma, steatocystoma multiplex and trichoepithelioma. A dermatoscopy examination was performed to differentiate these skin lesions. The dermatoscopic images revealed circular or quasi-circular whitish amorphous structure with a central brownish keratin plug, providing the diagnostic clues of T. marneffei infection. Therefore, a skin scrapings culture, skin biopsy and serological detection for human immunodeficiency virus (HIV) were performed. The final diagnosis of this patient was T. marneffei and HIV co-infection. CONCLUSION: Rapid diagnosis of T. marneffei infection is clinically challenging since presenting clinical manifestations are nonspecific with significant overlap with other common conditions. This case highlights that dermatoscopy is a promising tool for the rapid diagnosis of T. marneffei infection in patients with nonspecific skin lesions, assisting clinicians to avoid delayed diagnosis or misdiagnosis.


Assuntos
Dermoscopia/métodos , Micoses/diagnóstico , Talaromyces/patogenicidade , Anfotericina B/uso terapêutico , Fármacos Anti-HIV/uso terapêutico , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , China , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Humanos , Itraconazol/administração & dosagem , Itraconazol/uso terapêutico , Masculino , Micologia/métodos , Micoses/tratamento farmacológico , Adulto Jovem
7.
Med Mycol ; 57(Supplement_3): S259-S266, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31292661

RESUMO

The field of diagnostic mycology represents much more than culture and microscopy and is rapidly embracing novel techniques and strategies to help overcome the limitations of conventional approaches. Commercial molecular assays increase the applicability of PCR testing and may identify markers of antifungal resistance, which are of great clinical concern. Lateral flow assays simplify testing and turn-around time, with potential for point of care testing, while proximity ligation assays embrace the sensitivity of molecular testing with the specificity of antibody detection. The first evidence of patient risk stratification is being described and together with the era of next generation sequencing represents an exciting time in mycology.


Assuntos
Micologia/tendências , Micoses/diagnóstico , Técnicas de Laboratório Clínico/tendências , Humanos
8.
J Ethnobiol Ethnomed ; 15(1): 36, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31315635

RESUMO

BACKGROUND: The Guatemalan Highlands is a region of great but so far poorly known mycological diversity. People living in this area have long used wild fungi as a source of food and income. However, our knowledge of the ethnomycological practices of the Mayan peoples of Guatemala is still rudimental, especially if compared with information reported for the neighboring region of Mexico. Among the main indigenous groups of the Maya people inhabiting the highlands of Central Guatemala, stand the Kaqchikel, accounting for nearly 8% of the entire Guatemalan population. The main aim of this study was to record the traditional knowledge and use of edible wild mushrooms by inhabitants of the municipality of San Juan Sacatepéquez that lies at the heart of the Kaqchikel area in the central highlands of Guatemala, also describing the relevant selling practices and dynamics. A secondary aim was to compare the diversity and composition of the mushroom assemblage offered at the market with the macrofungal diversity of woods in the area. METHODOLOGY: This study is the result of 4 years of ethnomycological research, conducted through continuous visits to the municipal market and focused interviews with collectors and vendors. Field sampling in pine-oak forested areas surrounding San Juan Sacatepéquez, from where the mushrooms sold at the market are foraged, were also conducted, in the presence of local collectors. RESULTS: The results show a significant richness of species sold in the market, a network of commerce of purchase, sale, and resale of several species, with relatively stable prices, and knowledge about edible and inedible species that is transmitted mainly within the family nucleus. The business of selling mushrooms in the market is an exclusive activity of women, who are supplied by collectors or by other vendors. Fungi are sold and bought only as food, while no consumption of hallucinogenic mushrooms or medicinal mushrooms was recorded. Several species of Amanita, Cantharellus, Boletus, Lactarius, and Russula were those most commercialized in the 4 years of the study, but we also spotted fungi never reported before as consumed in the country, including Gastropila aff. fumosa (= Calvatia fumosa) and several species of Cortinarius. Field sampling in nearby pine-oak forests confirmed an elevated local macrofungal diversity. CONCLUSION: Our study unveiled the contemporary wealth of Kaqchikel culture for what concerns mushrooms, demonstrating that mushrooms continue to be culturally and economically important for these communities despite the erosion of traditional knowledge. Our results also confirmed the need to investigate in greater detail the Guatemalan mycodiversity that is vast and poorly known.


Assuntos
Agaricales/classificação , Biodiversidade , Comércio/economia , Micologia/métodos , Adulto , Países em Desenvolvimento , Feminino , Guatemala , Humanos , Povos Indígenas , Conhecimento , Masculino , Micologia/economia
9.
Adv Neonatal Care ; 19(6): E3-E10, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31246615

RESUMO

BACKGROUND: Despite availability of rapid fungal potassium hydroxide (KOH) tests, many care providers rely on visual assessment to determine the diagnosis of monilial diaper dermatitis (MDD). PURPOSE: To determine whether a KOH test, when MDD is suspected, would result in more accurate diagnoses, with decreased antifungal medication prescription and exposure. METHODS: Quality improvement project from 2016 through 2017 with protocol implemented in 2017 for treatment of MDD after positive KOH testing. If monilial rash suspected, after 2 negative KOH tests, then antifungal ordered (considered false negative). χ testing and cost determination were performed. SAMPLE: Neonates in 2 level III neonatal intensive care units. OUTCOME VARIABLES: KOH test results, use of antifungal medication, and cost. RESULTS: The patient census included 1051 and 1015 patients in the year before and after the protocol initiation. The medical orders for antifungal medication decreased from 143 to 36 (P < .001; 95% odds ratio confidence interval, 2.24-4.38). There was a 75% reduction in both use and cost, as charged, of antifungal agents. Overall charges, including KOH test costs, decreased by 12%. Three infants received multiple negative KOH tests, then a positive one. These met the definition of false-negative tests, per protocol. There were no cases of fungal sepsis. IMPLICATIONS FOR PRACTICE: Use of a quality improvement protocol, in which the use of KOH testing is required, before antifungal agents are prescribed, results in decreased exposure and costs. IMPLICATIONS FOR RESEARCH: To test the feasibility of bedside "point-of-care" KOH testing, and whether KOH testing and reduced antifungal medication use affects antimicrobial resistance or invasive fungal sepsis.


Assuntos
Antifúngicos , Candidíase Cutânea , Dermatite das Fraldas , Hidróxidos/farmacologia , Sobremedicalização , Compostos de Potássio/farmacologia , Antifúngicos/economia , Antifúngicos/uso terapêutico , Candidíase Cutânea/diagnóstico , Candidíase Cutânea/etiologia , Análise Custo-Benefício , Dermatite das Fraldas/diagnóstico , Dermatite das Fraldas/microbiologia , Dermatite das Fraldas/prevenção & controle , Feminino , Humanos , Indicadores e Reagentes/farmacologia , Recém-Nascido , Masculino , Sobremedicalização/economia , Sobremedicalização/prevenção & controle , Micologia/métodos , Melhoria de Qualidade
10.
Niger Postgrad Med J ; 26(2): 94-99, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31187748

RESUMO

Background: The actual burden of fungal infections in Nigeria is uncertain due to the dearth of research in medical mycology. Evidence generated from dissertations is often overlooked, becoming moribund if not appropriately disseminated. The objectives of this study were to assess dissertations submitted to the Faculty of Pathology, National Postgraduate Medical College of Nigeria, for medical mycology-centred research and ascertain their dissemination by scientific communication. Materials and Methods: Dissertations accepted by the faculty of pathology from 1980 to 2017 were analysed and categorised into respective subdisciplines. Medical microbiology dissertations were further categorised into bacteriology, parasitology, virology and mycology. The proportion of titles under each subcategory was determined. A literature search was conducted to determine if mycology-related dissertations were published in peer-reviewed journals. Results: Six hundred dissertations were indexed under the faculty of pathology. There were 95 (15.8%) medical microbiology dissertations. The distribution of subject matter was bacteriology 62 (65.3%), parasitology 13 (13.7%), virology 15 (15.8%) and mycology 5 (5.3%). Two dissertations in anatomic pathology dealt with fungi. Mycology-related dissertations accounted for 0.8% of all dissertations submitted. Research focused on Candida, Histoplasma capsulatum var. duboisii, dermatophytes and others. At least 57.1% of mycology-related dissertations were disseminated by means of publication in peer-reviewed journals and/or abstract at scientific conferences. Conclusion: Mycology is a neglected research domain amongst post-graduates in the faculty. Scientific communication of research findings was above average.


Assuntos
Dissertações Acadêmicas como Assunto , Comunicação , Micologia , Patologia/educação , Educação de Pós-Graduação em Medicina , Docentes , Humanos , Nigéria , Universidades
11.
Hautarzt ; 70(8): 575-580, 2019 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-31098690

RESUMO

BACKGROUND: Many dermatologists do not understand the perpetual adjustments in the dermatophyte nomenclature. OBJECTIVES: The aim is to explain the background and the development of methods that have led to previous and current changes of dermatophyte taxonomy and to the detection of new dermatophytes. METHODS: In this article we evaluate the recent literature on this topic and our own results in the fields of dermatophyte identification, their detection, and of the associated taxonomic developments. RESULTS: Today, the phylogenetic species concept is the basis of taxonomic classification, including that of dermatophytes. Genetic techniques have decisively advanced this and are state of the art nowadays. The detection of new dermatophyte species was often triggered by clinical observations and by morphologically conspicuous cultures that prompted their subsequent exact mycological characterization. Even today not all species of dermatophytes are unequivocally defined. CONCLUSIONS: By exclusively using selected genetic characteristics for the construction of phylogenetic trees additional taxonomically relevant features are neglected. Therefore it is necessary to better integrate data derived from morphologic, physiologic, ecologic and pathophysiologic observations into phylogenetic analyses. Dermatologists are still asked to contribute such information.


Assuntos
Arthrodermataceae/classificação , Classificação/métodos , Dermatomicoses/diagnóstico , Micologia/métodos , Filogenia , Polimorfismo Genético , Arthrodermataceae/genética , Arthrodermataceae/isolamento & purificação , Humanos , Técnicas de Tipagem Micológica , Análise de Sequência de DNA , Especificidade da Espécie
12.
Rev Iberoam Micol ; 36(2): 61-65, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31078386

RESUMO

BACKGROUND: The gold standard for the sporotrichosis diagnosis is culture; however, serologic approaches have been recently implemented to aid in the sporotrichosis diagnosis. Nevertheless, the clinical consequences of the introduction of serologic tests are poorly addressed. AIMS: To correlate the results of culture and serology of patients with suspected sporotrichosis. METHODS: A retrospective study of 198 patients with suspected sporotrichosis was conducted. Information about culture isolation of Sporothrix from clinical samples and antibody detection by an enzyme-linked immunosorbent assay (ELISA) were obtained from the medical records of the patients. RESULTS: Positive culture and antibody detection was observed in the samples of 84 patients (42.4%). Forty-one samples (20.7%) showed negative results with both techniques and divergent results were obtained in the samples of 73 patients (36.9%). False negative results in the ELISA were observed with 23 patients (31.5%), 78.3% of them with less than 30 days of infection (p=0.0045). Among the initial false positive ELISA in the sera of 50 patients, four samples in culture yielded the growth of Sporothrix, and 27 improved with itraconazole. At the end of follow-up, a diagnosis of proven or probable sporotrichosis was established in 139 patients, and possible sporotrichosis in 11 patients. The treatment of the patients with probable sporotrichosis with antifungal drugs resulted in clinical cure for these individuals. CONCLUSIONS: These two techniques are complementary in the diagnosis of sporotrichosis, making diagnosis and clinical decision more precise.


Assuntos
Micologia/métodos , Testes Sorológicos , Sporothrix/isolamento & purificação , Esporotricose/diagnóstico , Adolescente , Adulto , Idoso , Anticorpos Antifúngicos/análise , Antifúngicos/uso terapêutico , Criança , Pré-Escolar , Estudos Transversais , Ensaio de Imunoadsorção Enzimática/estatística & dados numéricos , Reações Falso-Positivas , Feminino , Humanos , Itraconazol/uso terapêutico , Masculino , Pessoa de Meia-Idade , Resultados Negativos/estatística & dados numéricos , Estudos Retrospectivos , Testes Sorológicos/estatística & dados numéricos , Sporothrix/imunologia , Esporotricose/tratamento farmacológico , Adulto Jovem
13.
Biopreserv Biobank ; 17(5): 395-400, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30938541

RESUMO

Subculturing is frequently used for the preservation of basidiomycetes. In this study, to assess and verify the risks of repeated subculturing on the long-term preservation of strains of culture collections, we performed single nucleotide polymorphism (SNP) analysis in genes encoding enzymes of the mevalonate pathway, 1,3-ß-glucan synthesis, lignin degradation, and the tricarboxylic acid (TCA) cycle of mycelia before and after preserving for a 4-year period by the subculturing 30 times every 45 days of Ganoderma lucidum NBRC 8346. As a result of analyzing 60 genes of the strain, SNPs were found in 18 genes, and 14 of them were found in the exon region. Nonsynonymous coding SNPs were found in two genes (atoB_2, hmgr) encoding enzymes of mevalonate pathway and five genes (lcc1_9, lcc1_11, lcc1_13, dslcc6, aa5_1_9) encoding enzymes of lignin degradation after subculturing of G. lucidum NBRC 8346.


Assuntos
Proteínas Fúngicas/genética , Micologia/métodos , Polimorfismo de Nucleotídeo Único , Reishi/crescimento & desenvolvimento , Éxons , Sequenciamento de Nucleotídeos em Larga Escala , Preservação Biológica , Reishi/genética , Análise de Sequência de DNA
14.
mSphere ; 4(2)2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30894430

RESUMO

Regular protocols for the isolation of fungal extracellular vesicles (EVs) are time-consuming, hard to reproduce, and produce low yields. In an attempt to improve the protocols used for EV isolation, we explored a model of vesicle production after growth of Cryptococcus gattii and Cryptococcus neoformans on solid media. Nanoparticle tracking analysis in combination with transmission electron microscopy revealed that C. gattii and C. neoformans produced EVs in solid media. The properties of cryptococcal vesicles varied according to the culture medium used and the EV-producing species. EV detection was reproduced with an acapsular mutant of C. neoformans, as well as with isolates of Candida albicans, Histoplasma capsulatum, and Saccharomyces cerevisiae Cryptococcal EVs produced in solid media were biologically active and contained regular vesicular components, including the major polysaccharide glucuronoxylomannan (GXM) and RNA. Since the protocol had higher yields and was much faster than the regular methods used for the isolation of fungal EVs, we asked if it would be applicable to address fundamental questions related to cryptococcal secretion. On the basis that polysaccharide export in Cryptococcus requires highly organized membrane traffic culminating with EV release, we analyzed the participation of a putative scramblase (Aim25; CNBG_3981) in EV-mediated GXM export and capsule formation in C. gattii EVs from a C. gattii aim25Δ strain differed from those obtained from wild-type (WT) cells in physical-chemical properties and cargo. In a model of surface coating of an acapsular cryptococcal strain with vesicular GXM, EVs obtained from the aim25Δ mutant were more efficiently used as a source of capsular polysaccharides. Lack of the Aim25 scramblase resulted in disorganized membranes and increased capsular dimensions. These results associate the description of a novel protocol for the isolation of fungal EVs with the identification of a previously unknown regulator of polysaccharide release.IMPORTANCE Extracellular vesicles (EVs) are fundamental components of the physiology of cells from all kingdoms. In pathogenic fungi, they participate in important mechanisms of transfer of antifungal resistance and virulence, as well as in immune stimulation and prion transmission. However, studies on the functions of fungal EVs are still limited by the lack of efficient methods for isolation of these compartments. In this study, we developed an alternative protocol for isolation of fungal EVs and demonstrated an application of this new methodology in the study of the physiology of the fungal pathogen Cryptococcus gattii Our results describe a fast and reliable method for the study of fungal EVs and reveal the participation of scramblase, a phospholipid-translocating enzyme, in secretory processes of C. gattii.


Assuntos
Cryptococcus gattii/enzimologia , Vesículas Extracelulares/química , Polissacarídeos Fúngicos/química , Proteínas Fúngicas/genética , Micologia/métodos , Transporte Biológico , Cryptococcus gattii/genética , Cryptococcus neoformans/citologia , Cryptococcus neoformans/genética , Vesículas Extracelulares/ultraestrutura , Microscopia Eletrônica de Transmissão , Polissacarídeos/genética , Polissacarídeos/isolamento & purificação
15.
Curr Protoc Microbiol ; 53(1): e75, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30661293

RESUMO

The Cryptococcus pathogenic species complex is a group of opportunistic human fungal pathogens that cause cryptococcal meningoencephalitis, an infection associated with unacceptably high mortality rates. The public health relevance of these pathogens has galvanized extensive research over the past several decades and led to characterization of their sexual cycles. This research has allowed several Cryptococcus species to develop into model fungal organisms for both pathogenesis and basic science studies. Many of these studies require observation of the meiotic process and its associated mating structures as well as generation of meiotic progeny with novel phenotypes and genotypes. Herein, we describe how to set up genetic crosses between Cryptococcus strains and observe their mating phenotypes as well as how to recover progeny from these crosses for further analysis. © 2019 by John Wiley & Sons, Inc.


Assuntos
Cruzamentos Genéticos , Cryptococcus neoformans/genética , Técnicas Genéticas , Micologia/métodos , Criptococose/microbiologia , Cryptococcus neoformans/crescimento & desenvolvimento , Meios de Cultura/química , Meios de Cultura/metabolismo , Genes Fúngicos Tipo Acasalamento , Genótipo , Humanos , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento
16.
Rev Iberoam Micol ; 36(1): 9-16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30686747

RESUMO

BACKGROUND: Invasive candidiasis by Candida albicans is associated with high morbidity and mortality, due in part to the late implementation of an appropriate antifungal therapy hindered by the lack of an early diagnosis. AIMS: We aimed to evaluate the in vitro antifungal activity of the antibodies against C. albicans germ tubes (CAGTA) raised in a rabbit model of candidemia. METHODS: We measured the effect of CAGTA activity by colorimetric XTT and crystal violet assays, and colony forming units count, both on C. albicans planktonic cells and during the course of biofilm formation and maturation. Viability and cell morphology were assessed by optical, fluorescent or scanning electron microscopy. RESULTS: CAGTA ≥50µg/ml caused a strong inhibition of C. albicans blastospores growth, and DiBAC fluorescent staining evidenced a fungicidal activity. Moreover, electron microscopy images revealed that CAGTA induced morphological alterations of the surface of C. albicans germ tubes grown free as well as in biofilm. Interestingly, CAGTA ≥80µg/ml reduced the amount of C. albicans biofilm, and this effect started at the initial adhesion stage of the biofilm formation, during the first 90min. CONCLUSIONS: This is the first report showing that CAGTA reduce C. albicans growth, and impair its metabolic activity and ability to form biofilm in vitro. The antigens recognized by CAGTA could be the basis for the development of immunization protocols that might protect against Candida infections.


Assuntos
Anticorpos Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Estruturas Fúngicas/imunologia , Candida albicans/crescimento & desenvolvimento , Micologia/métodos
19.
Int J Dermatol ; 58(3): 319-324, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30246397

RESUMO

BACKGROUND: In the absence of a real gold standard, comparative studies are still done on diagnostic methods for onychomycosis. There are only a few attempts using latent class analysis to determine the value of polymerase chain reaction in comparison to conventional methods. We aimed to determine the value of histological examination in such a way for the diagnosis of onychomycosis. METHODS: Potassium hydroxide mount (KOH), culture and histological examination with periodic acid-Schiff (PAS), and Gomori's methenamine silver (GMS) stains were done in 106 patients having clinically suspected toenail onychomycosis. RESULTS: KOH was positive in 74% of the patients; culture in 14%; PAS in 30%; and GMS in 66%. According to the results of the latent class analysis, culture and PAS were highly specific but poorly sensitive; KOH, highly sensitive but poorly specific; and GMS, both highly sensitive and specific. CONCLUSIONS: Based on these results, we have proposed KOH as a screening test and GMS as a confirmatory test for the diagnosis of onychomycosis in our own practice. However, since positivity rates of different diagnostic methods vary widely in different centers, it is more suitable that every center should determine their own diagnostic strategy by evaluating their own results with latent class analysis.


Assuntos
Onicomicose/diagnóstico , Onicomicose/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Corantes , Feminino , Humanos , Hidróxidos , Indicadores e Reagentes , Análise de Classes Latentes , Masculino , Metenamina , Pessoa de Meia-Idade , Micologia/métodos , Onicomicose/microbiologia , Reação do Ácido Periódico de Schiff , Compostos de Potássio , Sensibilidade e Especificidade , Adulto Jovem
20.
Mycorrhiza ; 29(1): 1-11, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30324505

RESUMO

Empirical and taxonomic approaches are the two main methods used to assign plant mycorrhizal traits to species lists. While the empirical approach uses only available empirical information, the taxonomic approach extrapolates certain core information about plant mycorrhizal types and statuses to related species. Despite recent claims that the taxonomic approach is now almost definitive, with little benefit to be gained from further empirical data collection, it has not been thoroughly compared with the empirical approach. Using the most complete available plant mycorrhizal trait information for Europe and both assignment approaches, we calculate the proportion of species for each trait, and model environmental drivers of trait distribution across the continent. We found large degrees of mismatch between approaches, with consequences for biogeographical interpretation, among facultatively mycorrhizal (FM; 91% of species mismatched), non-mycorrhizal (NM; 45%), and to a lesser extent arbuscular mycorrhizal (AM; 16%) plant species. This can partly be attributed to the taxonomic precision of the taxonomic approach and the use of different AM, NM, and FM concepts. Our results showed that the extrapolations of the taxonomic approach do not consistently match with empirical information and indicate that more empirical data are needed, in particular for FM, NM, and AM plant species. Clarifying certain concepts underlying mycorrhizal traits and empirically describing NM, AM, and FM species within plant families can greatly improve our understanding of the biogeography of mycorrhizal symbiosis.


Assuntos
Evolução Biológica , Botânica/métodos , Micologia/métodos , Micorrizas/fisiologia , Europa (Continente) , Plantas/microbiologia , Simbiose
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