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Item does not contain fulltext BACKGROUND: The skin is the first line of defence against communities of resident viruses, bacteria and fungi. The composition of the microbiome might change with factors related to the environment and host. The microbiome is dominated by bacteria. Dermatophytes and yeasts are the predominant fungi that are also involved in opportunistic infections of skin, hair and nails. Among environmental fungi, Chaetothyriales (black yeasts and relatives) are enriched by hydrocarbon pollution in domesticated habitats and comprise numerous species that cause mild-to-severe disease. METHODS: We investigated the presence of black fungi in the skin microbiome by conducting an analysis in the publicly available metagenomic SRA database (NCBI). We focused on the causative agents of chromoblastomycosis and phaeohyphomycosis and used barcodes and padlock probe sequences as diagnostic tools. RESULTS: A total of 132,159,577 MB was analysed and yielded 18,360 reads that matched with 24 species of black fungi. Exophiala was the most prevalent genus, and Cyphellophora europaea was the most abundant species. CONCLUSION: This study reveals the abundant presence of Chaetothyriales on the skin without necessarily being associated with infection. Most of the detected causal agents are known from mild skin diseases, while also species were revealed that had been reported from CARD9-deficient patients. 01 juni 2023

Made available in DSpace on 2020-12-12T01:57:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-01 National Council for Scientific Research Federal Agency for Scientific Organizations Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Chromoblastomycosis is a neglected disease characterized by cutaneous, subcutaneous or disseminated lesions. It is considered an occupational infectious disease that affects mostly rural workers exposed to contaminated soil and vegetal matter. Lesions mostly arise after a traumatic inoculation of herpotrichiellaceous fungi from the Chaetothyriales order. However, the environmental niche of the agents of the disease remains obscure. Its association with insects has been predicted in a few studies. Therefore, the present work aimed to analyze if social insects, specifically ants, bees, and termites, provide a suitable habitat for the fungi concerned. The mineral oil flotation method was used to isolate the microorganisms. Nine isolates were recovered and phylogenetic analysis identified two strains as potential agents of chromoblastomycosis, i.e., Fonsecaea pedrosoi CMRP 3076, obtained from a termite nest (n = 1) and Rhinocladiella similis CMRP 3079 from an ant exoskeleton (n = 1). In addition, we also identified Fonsecaea brasiliensis CMRP 3445 from termites (n = 1), Exophiala xenobiotica CMRP 3077 from ant exoskeleton (n = 1), Cyphellophoraceae CMRP 3103 from bees (n = 1), Cladosporium sp. CMRP 3119 from bees (n = 1), Hawksworthiomyces sp. CMRP 3102 from termites (n = 1), and Cryptendoxyla sp. from termites (n = 2). The environmental isolate of F. pedrosoi CMRP 3076 was tested in two animal models, Tenebrio molitor and Wistar rat, for its pathogenic potential with fungal retention in T. molitor tissue. In the Wistar rat, the cells resembling muriform cells were observed 30 d after inoculation. Graduate Program in Microbiology Parasitology and Pathology Federal University of Paraná University Center Campo Real Federal University of Paraná Graduate Program in Pharmacology UFPR Medical Department Federal University of Maranhão Embrapa Amazônia Oriental CPATU Westerdijk Fungal Biodiversity Institute Department of Biochemistry and Microbiology Institute of Biological Sciences UNESP-São Paulo State University Division of Microbial Resources CPQBA University of Campinas Center of Expertise in Mycology of Radboud University Medical Center Canisius Wilhelmina Hospital Department of Biochemistry and Microbiology Institute of Biological Sciences UNESP-São Paulo State University CNPq: 312811/2018–7 CAPES: Brazil CAPES: Finance Code 001, Brasilia

The biological control (BC) is an efficient tool in helping to reduce pests in crops of economic interest. In addition to the efficiency, there are advantages in using biological control agents, such as human safety and other non-target organisms and decreasing pesticide residues. The general aim of this work was to evaluate in vitro the pathogenicity power of fifteen Beauveria bassiana strains aiming the biological control of Drosophila suzukii (Matsumura, 1931). Successful infection of entomopathogenic fungi depends primarily on the adherence and penetration ability of a fungus to the host integuments. In addition, scanning electron microscopy was realized. To verify the spore adherence after the spraying tests, insects were collected throughout the bioassays in order to confirm spore evolution on the insect cuticle. In this work, D. suzukii adults were not susceptible to the aqueous suspensions of conidia at concentrations of 108 spores·mL−1 of these strains. There wasn’t death confirmed by fungus extrusion after maintenance in humid chamber. El control biológico es una herramienta eficaz para ayudar a reducir las plagas en los cultivos de interés económico. Además de la eficacia, el uso de estos agentes presenta ventajas, como la seguridad para los seres humanos y otros organismos y la reducción de los residuos de plaguicidas. El objetivo general de este estudio fue evaluar in vitro la patogenicidad de 15 cepas de Beauveria bassiana para el control biológico de Drosophila suzukii (Matsumura, 1931). Además, se sabe que el éxito de la infección de los hongos entomopatógenos depende principalmente de la adherencia y la capacidad de penetración de un hongo en los tegumentos del huésped y, por lo tanto, se realizó una microscopía electrónica. Para comprobar la adherencia de las esporas después de las pruebas de pulverización, se recogieron insectos a lo largo de los bioensayos para confirmar la evolución de las esporas en la cutícula del insecto.. En este trabajo, los adultos de D. suzukii no fueron susceptibles a las suspensiones acuosas de esporas en concentraciones de 108 esporas-mL-1 de estas cepas. No se confirmó la muerte por extrusión de hongos en la cámara húmeda. O controle biológico é uma ferramenta eficiente para ajudar a reduzir pragas em culturas de interesse econômico. Além da eficácia, as vantagens no uso destes agentes, a segurança para humanos e outros organismos não-alvo e a diminuição de resíduos de pesticidas são extremamente relevantes. O objetivo geral deste estudo foi avaliar in vitro a patogenicidade de 15 linhagens de Beauveria bassiana, anteriormente testadas contra outra praga de interesse, visando o controle biológico de Drosophila suzukii (Matsumura, 1931). Para uma infecção no hospedeiro bem-sucedida, os fungos entomopatogênicos dependem principalmente da aderência e capacidade de penetração nos tegumentos do hospedeiro. Sendo assim, foi realizada também uma microscopia eletrônica de varredura. Para verificar se houve aderência dos esporos após os testes de pulverização, foram coletados insetos durante os bioensaios, com o objetivo de confirmar a evolução dos esporos na cutícula dos insetos. Neste trabalho, adultos de D. suzukii não foram suscetíveis às suspensões aquosas de esporos em concentrações de 108 esporos-mL-1 de nenhuma das linhagens testadas, uma vez que não houve morte confirmada por extrusão de fungos após manutenção dos insetos em câmara úmida.

Simple Summary The use of fungi as biocontrol agents against insect pests can be an environmentally friendly alternative to the use of chemical pesticides. In this study, 15 fungal strains were isolated and identified as Beauveria bassiana, which is a fungus that can harm insects. Consequently, we tested these strains, under laboratory conditions, against adults of Lema bilineata Germar (Coleoptera: Chrysomelidae), which is an emerging pest in Brazil. These insects showed a great sensitivity to three of the fungal isolates tested. Then, these three fungal strains were applied to the eggs of this insect and showed a rather high ovicidal capacity. Our findings showed that these fungal isolates, which have pathogenic potential as biocontrol agents against L. bilineata, are a promising alternative to chemical insecticides. However, these results must be expanded with experiments in open fields. Abstract Lema bilineata Germar (Coleoptera: Chrysomelidae) was recently reported to damage Physalis peruviana crops in Brazil. Given the potential for inflicting damage on other Solanaceae species and the lack of alternatives for controlling this pest, we assessed the pathogenicity of 15 Beauveria isolates against L. bilineata adults in vitro. In addition, three of these isolates were tested for their ovicidal effect against L. bilineata eggs. Fungal strains were isolated from mummified corpses of L. bilineata collected in a non-commercial field in Paraná, Brazil. The isolates were identified as Beauveria bassiana using molecular markers. Lema bilineata adults were susceptible to conidial suspensions of all these isolates at a concentration of 108 conidia mL−1. Deaths caused by fungal extrusion were confirmed. Three strains were found to be more virulent against L. bilineata adults and showed ovicidal effects. This is the first study on entomopathogenic fungi isolated from dead insects collected from P. peruviana crops and tested against L. bilineata carried out in Brazil. The results obtained in the laboratory indicate the high potential of the use of three B. bassiana strains against L. bilineata as a biocontrol agent.

Fungal peritonitis is frequent on peritoneal dialysis, with rare cases by Exophiala dermatitidis. A 25-month-old female admitted to the pediatric ICU with acute renal failure was submitted to peritoneal dialysis. After 10 days patient presented fever. Peritoneal fluid culture showed yeast colonies molecularly identified as E. dermatitidis. Patient was treated with voriconazole and hemodialysis. The literature was reviewed. Disseminated infections are frequently fatal, but appropriate diagnose and therapeutic led to cure in this case. Keywords: Phaeohyphomycosis, Fungal infection, Dialysis, Therapeutic management, Molecular diagnosis

SARS-CoV-2 environmental monitoring can track the rate of viral contamination and can be used to establish preventive measures. This study aimed to detect by RT-PCR the presence of SARS-CoV-2 from inert surface samples in public health settings with a literature review about surface contamination and its burden on spread virus. Samples were collected from health settings in Curitiba, Brazil, between July and December 2020. A literature review was conducted using PRISMA. A total of 711 environmental surface samples were collected from outpatient areas, dental units, doctors’ offices, COVID-19 evaluation areas, and hospital units, of which 35 (4.9%) were positive for SARS-CoV-2 RNA. The frequency of environmental contamination was higher in primary care units than in hospital settings. The virus was detected on doctors’ personal items. Remarkably, the previously disinfected dental chair samples tested positive. These findings agree with those of other studies in which SARS-CoV-2 was found on inanimate surfaces. Detection of SARS-CoV-2 RNA on surfaces in public health settings, including those not meant to treat COVID-19, indicates widespread environmental contamination. Therefore, the intensification of disinfection measures for external hospital areas may be important for controlling community COVID-19 dissemination.

Chromoblastomycosis is a chronic, cutaneous or subcutaneous mycosis characterized by the presence of muriform cells in host tissue. Implantation disease is caused by melanized fungi related to black yeasts, which, in humid tropical climates, are mainly members of the genus Fonsecaea. In endemic areas of Brazil, F. pedrosoi and F. monophora are the prevalent species. The current hypothesis of infection is traumatic introduction via plant materials, especially by plant thorns. However, isolation studies have demonstrated a low frequency of the agents in environmental substrates. The present study aimed to detect F. pedrosoi and F. monophora in shells of babassu coconuts, soil, plant debris, and thorns from endemic areas of chromoblastomycosis in Maranhão state, northern Brazil, using Rolling Circle Amplification (RCA) with padlock probes as a new environmental screening tool for agents of chromoblastomycosis. In addition to molecular screening, the environmental samples were analyzed by fungal isolation using mineral oil flotation. The limit of detection of the RCA method was 2.88 × 107 copies of DNA per sample for the used padlock probes, indicating that this represents an efficient and sensitive molecular tool for the environmental screening of Fonsecaea agents. In contrast, with isolation from the same samples using several selective methods, no agents of chromoblastomycosis were recovered.

The species belonging to the genus Fonsecaea are the main causative agents of chromoblastomycosis. The invasive potential of Fonsecaea differs significantly among its various sibling species. Moreover, the lack of clarity on the virulence and availability of precise markers to distinguish and detect Fonsecaea species is attributed to the different ways of dissemination and pathogenicity. Therefore, the present study aimed to propose new molecular tools to differentiate between sibling species causing chromoblastomycosis. We used an infection model of chromoblastomycosis in BALB/c to study species-specific molecular markers for the in vivo detection of Fonsecaea species in biological samples. Specific primers based on the CBF5 gene were developed for Fonsecaea pedrosoi, Fonsecaea monophora, Fonsecaea nubica, and Fonsecaea pugnacius. In addition, a padlock probe was designed for F. pugnacius based on ITS sequences. We also assessed the specificity of Fonsecaea species using in silico, in vitro, and in vivo assays. The results showed that markers and probes could effectively discriminate the species in both clinical and environmental samples, enabling bioprospecting of agents of chromoblastomycosis, thereby elucidating the infection route of the disease.

Chromoblastomycosis is a chronic, cutaneous or subcutaneous mycosis characterized by the presence of muriform cells in host tissue. Implantation disease is caused by melanized fungi related to black yeasts, which, in humid tropical climates, are mainly members of the genus Fonsecaea. In endemic areas of Brazil, F. pedrosoi and F. monophora are the prevalent species. The current hypothesis of infection is traumatic introduction via plant materials, especially by plant thorns. However, isolation studies have demonstrated a low frequency of the agents in environmental substrates. The present study aimed to detect F. pedrosoi and F. monophora in shells of babassu coconuts, soil, plant debris, and thorns from endemic areas of chromoblastomycosis in Maranhão state, northern Brazil, using Rolling Circle Amplification (RCA) with padlock probes as a new environmental screening tool for agents of chromoblastomycosis. In addition to molecular screening, the environmental samples were analyzed by fungal isolation using mineral oil flotation. The limit of detection of the RCA method was 2.88 × 107 copies of DNA per sample for the used padlock probes, indicating that this represents an efficient and sensitive molecular tool for the environmental screening of Fonsecaea agents. In contrast, with isolation from the same samples using several selective methods, no agents of chromoblastomycosis were recovered.

BackgroundTraditionally known as a common contaminant, Rhodotorula mucilaginosa is among the leading causes of invasive fungal infections by non-candida yeasts. They affect mainly immunocompromised individuals, often mimicking the cryptococcosis infection, despite invasive infections by Rhodotorula are still not well explained. Thus, here we aimed to characterize microbiologically clinical isolates of R. mucilaginosa isolated from colonization of a patient with chronic renal disease (CKD), as well as to evaluate their phylogeny, antifungal susceptibility, virulence, and pathogenicity in order to infer the potential to become a possible infection.Methodology/Principal FindingsFor this study, two isolates of R. mucilaginosa from oral colonization of a CKD patient were isolated, identified and characterized by classical (genotypic and phenotypic) methods. Susceptibility to conventional antifungals was evaluated, followed by biofilm production, measured by different techniques (total biomass, metabolic activity, colony forming units and extracellular matrix quantification). Finally, the pathogenicity of yeast was evaluated by infection of Tenebrio molitor larvae.All isolates were resistant to azole and sensitive to polyenes and they were able to adhere and form biofilm on the abiotic surface of polystyrene. In general, similar profiles among isolates were observed over the observed periods (2, 24, 48 and 72 hours). Regarding extracellular matrix components of biofilms at different maturation ages, R. mucilaginosa was able to produce eDNA, eRNA, proteins, and polysaccharides that varied according to time and the strain. The death curve in vivo model showed a large reduction in the survival percentage of the larvae was observed in the first 24 hours, with only 40% survival at the end of the evaluation.Conclusions/SignificanceWe infer that colonization of chronic renal patients by R. mucilaginosa offers a high risk of serious infection. And also emphasize that the correct identification of yeast is the main means for an efficient treatment.Author SummaryThe genus Rhodotorula is known to be a common contaminant, however, it has been increasing in the last years, reports of different forms infections by this yeast, reaching mainly individuals with secondary diseases or with low immunity. However, very little is known about the mechanism that triggers the disease. Thus, this study aims to characterize microbiologically clinical isolates of R. mucilaginosa isolated from a patient with chronic renal disease, as well as to evaluate their phylogeny, antifungal susceptibility, virulence, and pathogenicity in order to infer the potential to become a possible infection. It was possible to characterize in general the clinical isolates, to determine that they are resistant to an important class of the antifungal agents which are the azoles. In addition, they are able to adhere and to form biofilm on abiotic surfaces, this skill represents an important factor of virulence, which would guarantee their presence in medical devices, such as catheters, surfaces. These biofilm works as true reservoirs of these fungi disseminate and cause serious infections. This pathogenic potential was reinforced by a great reduction of survival in the larvae infected with this yeast. Therefore our results infer a high risk of infection to patients who are colonized by R. mucilaginosa.

Following a fatal case of Cryptococcus neoformans meningitis in a child with X-linked hyper-immunoglobulin M syndrome (XHIGM), we evaluated the fungal isolate in an experimental infection in a mouse model with respect to microbiology, epidemiology, virulence and response to therapy. The minimum inhibitory concentrations for antifungals in the susceptibility test were 0.5 mg/L for amphotericin B, 4.0 mg/L for fluconazole and 0.12 mg/L for voriconazole. Evaluation of pathogenicity by means of an experimental infection in BALB/c mice showed that fungus isolated from the blood and cerebrospinal fluid of the child was able to disseminate, reaching the spleen, lungs and brain, where it caused significant macroscopic alterations in the size and texture of each organ. Treatment of infected mice with amphotericin B reduced the fungal load in the spleen and lungs, but not in the brain.

Onychomycosis is a chronic fungal infection of nails, commonly caused by dermatophyte fungi, primarily species of Trichophyton. Because of the limited drug arsenal available to treat general fungal infections and the frequent failure of onychomycosis treatment, the search for new therapeutic sources is essential, and topical treatment with natural products for onychomycosis has been encouraged. Propolis, an adhesive resinous compound produced by honeybees (Apis mellifera), has shown multiple biological properties including significant antifungal and anti-biofilm activities in vitro. In spite of promising in vitro results, in vivo results have not been reported so far. This study assessed an ethanol propolis extract (PE) as a topical therapeutic option for onychomycosis, including its characterization in vitro and its applicability as a treatment for onychomycosis (from bench to clinic). The in vitro evaluation included analysis of the cytotoxicity and the antifungal activity against the planktonic cells and biofilm formed by Trichophyton spp. We also evaluated the capacity of PE to penetrate human nails. Patients with onychomycosis received topical PE treatments, with a 6-month follow-up period. The results of the in vitro assays showed that PE was non-toxic to the cell lines tested, and efficient against both the planktonic cells and the biofilm formed by Trichophyton spp. The results also showed that PE is able to penetrate the human nail. The results for PE applied topically to treat onychomycosis were promising, with complete mycological and clinical cure of onychomycosis in 56.25% of the patients. PE is an inexpensive commercially available option, easy to obtain and monitor. Our results indicated that PE is a promising natural compound for onychomycosis treatment, due to its ability to penetrate the nail without cytotoxicity, and its good antifungal performance against species such as Trichophyton spp. that are resistant to conventional antifungals, both in vitro and in patients.