Publications by authors named "Zoilo Pires de Camargo"

102 Publications

Clinical and epidemiological aspects of feline sporotrichosis caused by Sporothrix brasiliensis and in vitro antifungal susceptibility.

Vet Res Commun 2021 Jun 15. Epub 2021 Jun 15.

Department of Dermatological, Infectious, and Parasitic Diseases, School of Medicine (FAMERP), São José Do Rio Preto, São José do Rio Preto, Brazil.

Sporotrichosis is a subcutaneous mycosis resulting from the traumatic implantation of pathogenic Sporothrix species. In Brazil, zoonotic transmission plays an important role in the epidemiology of the disease, involving especially cats. The objective of this study was to isolate Sporothrix spp. from cats with signs of sporotrichosis, determining the causative species, clinical and epidemiological aspects, and the in vitro susceptibility profile of the isolates against antifungal drugs. From September 2017 to February 2019, 245 samples of lesions were collected from symptomatic cats in São José do Rio Preto, Brazil. Identification of the isolates was performed by morphophysiological parameters and species-specific polymerase chain reaction. The susceptibility profile of the isolates was determined for five drugs (amphotericin B, itraconazole, ketoconazole, potassium iodide and terbinafine), using the broth microdilution method. Clinical and epidemiological aspects were analyzed based on data contained on investigation forms filled by the veterinarians at moment of collection. Sporothrix spp. were isolated in 189 (77.2%) of the samples. Phenotypic and molecular analyses revealed S. brasiliensis as the only causative agent. In vitro susceptibility testing showed lower MIC values for terbinafine (MIC = 0.03-2 μg/ml), ketoconazole (MIC = 0.03-2 μg/ml), and itraconazole (MIC = 0.03-4 μg/ml). Most of the animals were male (73.5%), adults (96.3%), stray (53.5%), and uncastrated (69.8%). Our results show the expansion of the S. brasiliensis epidemic to an area nearly 840 km apart from the epicenter of the long-lasting outbreak of cat-transmitted sporotrichosis in Rio de Janeiro.
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http://dx.doi.org/10.1007/s11259-021-09795-2DOI Listing
June 2021

Puzzling paracoccidioidomycosis: Factors associated with the severity of Paracoccidioides lutzii infections.

Int J Infect Dis 2021 Jun 12;107:284-290. Epub 2021 May 12.

Júlio Muller University Hospital, Federal University of Mato Grosso, Cuiabá, Mato Grosso, Brazil; Laboratory of Mycology/Research, Faculty of Medicine, Federal University of Mato Grosso, Cuiabá, Mato Grosso, Brazil. Electronic address:

Objectives: Historically, the Brazilian Central-West region has had high numbers of paracoccidioidomycosis (PCM) cases caused by the dimorphic fungus Paracoccidioides lutzii.

Methods: This epidemiological, observational, analytical, cross-sectional study was performed to investigate the clinical and laboratory data of 44 PCM patients with a culture-proven P. lutzii infection. All patients were referred to the Systemic Mycosis Center, Júlio Muller University Hospital, Cuiabá, Brazil, during January 2017 to March 2020. The neutrophil to lymphocyte ratio (NLR) was calculated and dichotomized by its median value to include in the identification of factors associated with severity.

Results: At admission, 13 (31.7%) patients showed the disseminated multifocal chronic form of PCM and 16 (36.4%) patients met the clinical severity criteria. Treatment prescribed on admission did not follow the recommendations of the Brazilian Guideline for the Clinical Management of Paracoccidioidomycosis in 26% of the severe PCM cases (prevalence ratio 0.26, 95% confidence interval 0.14-0.49; P < 0.0001). Patients with severe PCM had a higher NLR that was greater than the median (≥4.11).

Conclusions: The NLR biomarker complements the criteria for PCM severity. Applying the low-cost NLR test can greatly increase the diagnostic sensitivity when screening patients for PCM and contribute to better control of the disease, management of complications, and therapeutic strategies.
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http://dx.doi.org/10.1016/j.ijid.2021.05.002DOI Listing
June 2021

and Biofilms Produce Antifungal-Tolerant Persister Cells.

Front Cell Infect Microbiol 2021 22;11:645812. Epub 2021 Apr 22.

Faculty of Medicine, Federal University of Ceará, Fortaleza, Brazil.

Persister cells are metabolically inactive dormant cells that lie within microbial biofilms. They are phenotypic variants highly tolerant to antimicrobials and, therefore, associated with recalcitrant infections. In the present study, we investigated if and are able to produce persister cells. spp. are ubiquitous fungi, commonly found as commensals of the human skin and gut microbiota, and have been increasingly reported as agents of fungemia in immunocompromised patients. Biofilms derived from clinical strains of (n=5) and (n=7) were formed in flat-bottomed microtiter plates and incubated at 35°C for 48 h, treated with 100 μg/ml amphotericin B (AMB) and incubated at 35°C for additional 24 h. Biofilms were scraped from the wells and persister cells were assayed for susceptibility to AMB. Additionally, we investigated if these persister cells were able to generate new biofilms and studied their ultrastructure and AMB susceptibility. Persister cells were detected in both and biofilms and showed tolerance to high doses of AMB (up to 256 times higher than the minimum inhibitory concentration). Persister cells were able to generate biofilms, however they presented reduced biomass and metabolic activity, and reduced tolerance to AMB, in comparison to biofilm growth control. The present study describes the occurrence of persister cells in spp. and suggests their role in the reduced AMB susceptibility of . and biofilms.
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http://dx.doi.org/10.3389/fcimb.2021.645812DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8100310PMC
July 2021

Paracoccidioidomycosis due to P lutzii: The importance of neutrophil/lymphocyte ratio in the symptomatic and asymptomatic phases in severe cases.

Mycoses 2021 Aug 27;64(8):874-881. Epub 2021 May 27.

Júlio Muller University Hospital, Federal University of Mato Grosso, Cuiabá, MT, Brazil.

Background: PCM is a neglected systemic mycosis endemic in Brazil. The middle-west region of Brazil has shown the highest number of PCM by Paracoccidioides lutzii (P lutzii) cases. Differentiating cases of severe PCM from non-severe ones should be a concern at the bedside. Diagnosis of severe PCM by P lutzii is based on the subjectivity of clinical manifestations, which can result in a delay in starting its treatment and, consequently evolution to severe sequelae. There is not laboratory biomarker available to support the early diagnosis of severe PCM that is feasible for all the realities that coexist in Brazil.

Objectives: The aim of this study was to investigate the usefulness of laboratory biomarkers as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and neutrophil/lymphocyte ratio (NLR) in the diagnosis of severe PCM.

Patients/methods: ESR, CRP and NLR were analysed for 44 patients with PCM by P lutzii and a Receiver Operation Characteristic (ROC) curve were generated to identify the NLR cut-off point and point out the presence of severe PCM.

Results: Sixteen (36.4%) had severe PCM and 28 (63.6%) had non-severe PCM. The mean NLR was higher and statistically significant among patients with severe PCM than among those with non-severe PCM. The area under the ROC curve was 0.859 for the diagnosis of severe PCM. The cut-off point for NLR for the diagnosis of severe PCM was 3.318 (sensitivity of 100%, specificity of 77%).

Conclusions: According to results, it is plausible to conclude that NLR represents a potential biomarker for the diagnosis of severe PCM.
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http://dx.doi.org/10.1111/myc.13282DOI Listing
August 2021

A New Duplex PCR-Assay for the Detection and Identification of Species.

J Fungi (Basel) 2021 Feb 26;7(3). Epub 2021 Feb 26.

Laboratory of Emerging Fungal Pathogens, Department of Microbiology, Immunology, and Parasitology, Discipline of Cellular Biology, Federal University of São Paulo (UNIFESP), São Paulo 04023062, Brazil.

Paracoccidioidomycosis (PCM) is a life-threatening systemic fungal infection caused by members of the complex and . Routine diagnoses of PCM down to the species level using classical mycological approaches are unspecific due to overlapping phenotypes. There is an urgent need for specific, sensitive, and cost-effective molecular tools to diagnose PCM. Variation among the exon-2 of the gp43 gene was exploited to design species-specific primer pairs to discriminate between members of the complex and in a duplex PCR assay. Primer-BLAST searches revealed highly species-specific primers, and no significant region of homology was found against DNA databases except for species. Primers PbraCx-F and PbraCx-R targeting DNA produced an amplicon of 308 bp, while primers Plu-F and Plu-R targeting DNA generated an amplicon of 142 bp. The lower limit of detection for our duplex PCR assay was 1 pg of gDNA. A panel of 62 revealed 100% specificity (AUC = 1.000, 95%CI 0.972-1.000, < 0.0001) without cross-reacting with other medically relevant fungi or human DNA. As a proof of concept, we demonstrated the accurate identification of the complex ( = 7) or ( = 6) from a broad range of formalin-fixed, paraffin-embedded (FFPE) tissues of PCM patient's organs. In four cases, FFPE PCR results confirmed, for the first time, co-infection due to (S1) and in the same biopsy. Our duplex PCR assay is useful to detect and differentiate members of the complex and , providing clinical laboratories with an important tool to be applied routinely, especially in atypical cases such as those featuring negative serology and positive mycological examination of clinical specimens as well as for the investigation of putative co-infection cases. This will likely benefit thousands of infected patients every year in a wide area of the Americas.
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http://dx.doi.org/10.3390/jof7030169DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7996757PMC
February 2021

Vancomycin enhances growth and virulence of Trichosporon spp. planktonic cells and biofilms.

Med Mycol 2021 Feb 7. Epub 2021 Feb 7.

Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará. Rua Cel. Nunes de Melo, 1315 - Rodolfo Teófilo - CEP: 60430-275, Fortaleza, Ceará, Brazil.

Invasive fungal infections (IFIs) are important worldwide health problem, affecting the growing population of immunocompromised patients. Although the majority of IFIs are caused by Candida spp., other fungal species have been increasingly recognized as relevant opportunistic pathogens. Trichosporon spp. are members of skin and gut human microbiota. Since 1980's, invasive trichosporonosis has been considered a significant cause of fungemia in patients with hematological malignancies. As prolonged antibiotic therapy is an important risk factor for IFIs, the present study investigated if vancomycin enhances growth and virulence of Trichosporon. Vancomycin was tested against T. inkin (n = 6) and T. asahii (n = 6) clinical strains. Planktonic cells were evaluated for their metabolic activity and virulence against Caenorhabditis elegans. Biofilms were evaluated for metabolic activity, biomass production, amphotericin B tolerance, induction of persister cells, and ultrastructure. Vancomycin stimulated planktonic growth of Trichosporon spp., increased tolerance to AMB, and potentiates virulence against C. elegans. Vancomycin stimulated growth (metabolic activity and biomass) of Trichosporon spp. biofilms during all stages of development. The antibiotic increased the number of persister cells inside Trichosporon biofilms. These cells showed higher tolerance to AMB than persister cells from VAN-free biofilms. Microscopic analysis showed that VAN increased production of extracellular matrix and cells in T. inkin and T. asahii biofilms. These results suggest that antibiotic exposure may have a direct impact on the pathophysiology of opportunistic trichosporonosis in patients at risk.

Lay Abstract: This study showed that the vancomycin stimulated Trichosporon growth, induced morphological and physiological changes on their biofilms, and also enhanced their in vivo virulence. Although speculative, the stimulatory effect of vancomycin on fungal cells should be considered in a clinical scenario.
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http://dx.doi.org/10.1093/mmy/myab001DOI Listing
February 2021

Molecular-based assessment of diversity and population structure of Sporothrix spp. clinical isolates from Espírito Santo-Brazil.

Mycoses 2021 Apr 28;64(4):420-427. Epub 2020 Dec 28.

Infectious Diseases Postgraduate Program, Center for Research in Medical Mycology, Federal University of Espírito Santo (UFES), Espírito Santo, Brazil.

Background: Sporotrichosis is a subcutaneous mycosis caused by Sporothrix species that affects humans and animals. Little information on the genetic diversity and population structure of the pathogen is available for Brazil, which is needed to design effective strategies to tackle the advance of sporotrichosis in endemic areas.

Objectives: We assessed the genetic diversity and mating-type distribution of Sporothrix isolates recovered from human and feline cases of sporotrichosis in Espírito Santo-Brazil to better understand the population structure, epidemiology and diversification of this pathogen, as well as to explore the possible routes of transmission involved in the ongoing outbreaks.

Methods: In all, 75 Sporothrix isolates were identified with phenotypic characteristics. Then, fungal DNA extraction was performed, and the species-specific PCR technique was applied, using markers directed to the calmodulin gene. The mating-type idiomorph of species was identified by PCR using primers targeting the MAT1-1 and MAT1-2 loci.

Results: Among the 75 Sporothrix isolates, 76% were confirmed as S brasiliensis and 24% as S schenckii sensu stricto. S brasiliensis was more prevalent in the metropolitan area and S schenckii s. str. in the mountainous region of the state. In both species, the presence of the two sexual idiomorphs was detected, suggesting that they are heterothallic species.

Conclusions: Our data suggest that sporotrichosis takes on an epidemic-urban character involving S brasiliensis. This species in Espírito Santo is likely to originate from Rio de Janeiro, as most isolates harbour the same MAT 1-2 locus. We confirm that S brasiliensis has significantly broadened its area of occurrence, an essential feature of emerging pathogens.
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http://dx.doi.org/10.1111/myc.13230DOI Listing
April 2021

Immunoproteomic Analysis Reveals Novel Candidate Antigens for the Diagnosis of Paracoccidioidomycosis Due to .

J Fungi (Basel) 2020 Dec 11;6(4). Epub 2020 Dec 11.

Laboratory of Emerging Fungal Pathogens, Department of Microbiology, Immunology, and Parasitology, Discipline of Cellular Biology, Federal University of São Paulo (UNIFESP), São Paulo 04023062, Brazil.

Paracoccidioidomycosis (PCM) is a life-threatening systemic infection caused by the fungal pathogen and related species. Whole-genome sequencing and stage-specific proteomic analysis of offer the opportunity to profile humoral immune responses against and infection using innovative screening approaches. Here, an immunoproteomic approach was used to identify PCM-associated antigens that elicit immune responses by combining 2-D electrophoresis of and proteomes, immunological detection using a gold-standard serum, and mass spectrometry analysis. A total of 16 and 25 highly immunoreactive proteins were identified in and , respectively, and 29 were shown to be the novel antigens for species, including seven uncharacterized proteins. Among the panel of proteins identified, most are involved in metabolic pathways, carbon metabolism, and biosynthesis of secondary metabolites in both immunoproteomes. Remarkably, six isoforms of the surface-associated enolase in the range of 54 kDa were identified as the major antigens in human PCM due to These novel immunoproteomes of will be employed to develop a sensitive and affordable point-of-care diagnostic assay and an effective vaccine to identify infected hosts and prevent infection and development of human PCM. These findings provide a unique opportunity for the refinement of diagnostic tools of this important neglected systemic mycosis, which is usually associated with poverty.
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http://dx.doi.org/10.3390/jof6040357DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7770604PMC
December 2020

Paracoccidioidomycosis due to Paracoccidioides brasiliensis S1 associated with acquired immunodeficiency syndrome: A case report.

Rev Iberoam Micol 2021 Jan-Mar;38(1):5-8. Epub 2020 Dec 13.

Universidade Federal do Espírito Santo-UFES, Brazil. Electronic address:

Background: Paracoccidioidomycosis (PCM) is an endemic disease in Latin America. In immunocompetent hosts, PCM occurs in two main clinical forms: acute and chronic. However, in HIV-infected patients PCM may show up simultaneous manifestations of acute and chronic forms.

Case Report: We present the case of a patient diagnosed with HIV who had disseminated skin lesions and generalized lymphadenopathy, as well as respiratory and central nervous system involvement. The PCM diagnosis was confirmed by direct KOH examination, double immunodiffusion and the isolation of the fungus in samples of an abscess in the subcostal region. The isolate was identified as Paracoccidioides brasiliensis S1 by species-specific PCR using primers for protein-coding gene GP43 (exon 2) followed by PCR-RFLP of the alpha-tubulin gene.

Conclusions: There are few data in literature reporting species-specific molecular identification of Paracoccidioides in HIV/PCM patients. Therefore, this case report may contribute to improve the knowledge about this severe disease, its causative cryptic species, and its consequences to patients.
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http://dx.doi.org/10.1016/j.riam.2020.09.003DOI Listing
December 2020

Biofilm formation on cat claws by Sporothrix species: An ex vivo model.

Microb Pathog 2021 Jan 4;150:104670. Epub 2020 Dec 4.

Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Forensic Medicine, Federal University of Ceará, Coronel Nunes de Melo Street, 1315 - Rodolfo Teófilo - 60430-275, Fortaleza, Ceará, Brazil; Postgraduate in Veterinary Sciences, Faculty of Veterinary, State University of Ceará. Dr. Silas Munguba Avenue, 1700, Itaperi Campus, 60714-903, Fortaleza, Ceará, Brazil.

This work aimed to evaluate the ability of Sporothrix species to attach and form biofilm on the surface of cat claws as an ex vivo model. A total of 14 strains (5 Sporothrix brasiliensis, 3 Sporothrix schenckii s. str., 3 Sporothrix globosa and 3 Sporothrix mexicana) were used. The biofilms were incubated for periods of 01, 03, 07, 10 and fifteenth 15 days. Their metabolic activities were evaluated by the XTT reduction assay and the morphology and structure were investigated by scanning electron microscopy (SEM). The analysis of the SEM images revealed that all the species can form biofilms on cat claws. The metabolic activity in the ex vivo biofilms was similar to that found in in vitro biofilms when incubated for the same period. This is the first report of an ex vivo biofilm model involving cat claws. The ability to form biofilms on cat claws can increase the viable period of the fungus and consequently the number of possibly infected animals and people.
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http://dx.doi.org/10.1016/j.micpath.2020.104670DOI Listing
January 2021

Molecular Tools for Detection and Identification of Species: Current Status and Future Perspectives.

J Fungi (Basel) 2020 Nov 18;6(4). Epub 2020 Nov 18.

Laboratory of Emerging Fungal Pathogens, Department of Microbiology, Immunology, and Parasitology, Discipline of Cellular Biology, Federal University of São Paulo (UNIFESP), São Paulo 04023062, Brazil.

Paracoccidioidomycosis (PCM) is a mycotic disease caused by the species, a group of thermally dimorphic fungi that grow in mycelial form at 25 °C and as budding yeasts when cultured at 37 °C or when parasitizing the host tissues. PCM occurs in a large area of Latin America, and the most critical regions of endemicity are in Brazil, Colombia, and Venezuela. The clinical diagnosis of PCM needs to be confirmed through laboratory tests. Although classical laboratory techniques provide valuable information due to the presence of pathognomonic forms of spp., nucleic acid-based diagnostics gradually are replacing or complementing culture-based, biochemical, and immunological assays in routine microbiology laboratory practice. Recently, taxonomic changes driven by whole-genomic sequencing of have highlighted the need to recognize species boundaries, which could better ascertain taxonomy. In this scenario, classical laboratory techniques do not have significant discriminatory power over cryptic agents. On the other hand, several PCR-based methods can detect polymorphisms in DNA and thus support species identification. This review is focused on the recent achievements in molecular diagnostics of paracoccidioidomycosis, including the main advantages and pitfalls related to each technique. We discuss these breakthroughs in light of taxonomic changes in the genus.
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http://dx.doi.org/10.3390/jof6040293DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7711936PMC
November 2020

Exogenous fungal quorum sensing molecules inhibit planktonic cell growth and modulate filamentation and biofilm formation in the complex.

Biofouling 2020 09 15;36(8):909-921. Epub 2020 Oct 15.

Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará. Rua Cel. Nunes de Melo, Fortaleza, Brazil.

This study investigated the effect of the quorum sensing molecules (QSMs) farnesol, 2-phenylehtanol, tyrosol and tryptophol against planktonic cells, filamentation and biofilms of spp. The antifungal activity of QSMs was evaluated by broth microdilution. QSMs showed MICs in the ranges of 0.01-1µM (farnesol), 1-8 mM (2-phenylehtanol and tyrosol), and >16 mM (tryptophol). Filamentous biofilm formation was inhibited by farnesol and 2-phenylehtanol and stimulated by tyrosol. Yeast biofilm formation was inhibited by 2-phenylehtanol and tyrosol. Tryptophol did not affect biofilm formation. QSMs showed MICs against mature biofilms of 8-32 µM (farnesol), 8-32 mM (2-phenylehtanol) and 64-128 mM (tyrosol). In conclusion, farnesol, 2-phenylethanol and tyrosol have antifungal activity against planktonic and sessile cells and modulate filamentation and biofilm formation in spp.
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http://dx.doi.org/10.1080/08927014.2020.1828373DOI Listing
September 2020

Genome-wide mapping using new AFLP markers to explore intraspecific variation among pathogenic Sporothrix species.

PLoS Negl Trop Dis 2020 07 1;14(7):e0008330. Epub 2020 Jul 1.

Laboratory of Emerging Fungal Pathogens, Department of Microbiology, Immunology, and Parasitology, Discipline of Cellular Biology, Federal University of São Paulo (UNIFESP), São Paulo, Brazil.

Sporotrichosis is a chronic subcutaneous mycosis caused by Sporothrix species, of which the main aetiological agents are S. brasiliensis, S. schenckii, and S. globosa. Infection occurs after a traumatic inoculation of Sporothrix propagules in mammals' skin and can follow either a classic route through traumatic inoculation by plant debris (e.g., S. schenckii and S. globosa) or an alternative route through zoonotic transmission from animals (e.g., S. brasiliensis). Epizootics followed by a zoonotic route occur in Brazil, with Rio de Janeiro as the epicenter of a recent cat-transmitted epidemic. DNA-based markers are needed to explore the epidemiology of these Sporothrix expansions using molecular methods. This paper reports the use of amplified-fragment-length polymorphisms (AFLP) to assess the degree of intraspecific variability among Sporothrix species. We used whole-genome sequences from Sporothrix species to generate 2,304 virtual AFLP fingerprints. In silico screening highlighted 6 primer pair combinations to be tested in vitro. The protocol was used to genotype 27 medically relevant Sporothrix. Based on the overall scored AFLP markers (97-137 fragments), the values of polymorphism information content (PIC = 0.2552-0.3113), marker index (MI = 0.002-0.0039), effective multiplex ratio (E = 17.8519-35.2222), resolving power (Rp = 33.6296-63.1852), discriminating power (D = 0.9291-0.9662), expected heterozygosity (H = 0.3003-0.3857), and mean heterozygosity (Havp = 0.0001) demonstrated the utility of these primer combinations for discriminating Sporothrix. AFLP markers revealed cryptic diversity in species previously thought to be the most prevalent clonal type, such as S. brasiliensis, responsible for cat-transmitted sporotrichosis, and S. globosa responsible for large sapronosis outbreaks in Asia. Three combinations (#3 EcoRI-FAM-GA/MseI-TT, #5 EcoRI-FAM-GA/MseI-AG, and #6 EcoRI-FAM-TA/MseI-AA) provide the best diversity indices and lowest error rates. These methods make it easier to track routes of disease transmission during epizooties and zoonosis, and our DNA fingerprint assay can be further transferred between laboratories to give insights into the ecology and evolution of pathogenic Sporothrix species and to inform management and mitigation strategies to tackle the advance of sporotrichosis.
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http://dx.doi.org/10.1371/journal.pntd.0008330DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7329091PMC
July 2020

inhibitory effect of statins on planktonic cells and biofilms of the species complex.

J Med Microbiol 2020 Jun 12;69(6):838-843. Epub 2020 May 12.

Postgraduate in Veterinary Sciences, Faculty of Veterinary, State University of Ceará, Fortaleza, Ceará, 60714-903, Brazil.

Sporotrichosis, caused by species of the complex, is the most prevalent subcutaneous mycosis in many areas of Latin America. Statins are a class of drugs widely used for lowering high sterol levels through their action on 3-hydroxy-3-methylglutaryl-CoA reductase, a key enzyme in the synthesis of sterol. In this study, the antifungal activity of statins (simvastatin, atorvastatin, pravastatin) against planktonic cells and biofilms of complex species was evaluated, as well as the interaction of pravastatin with classical antifungals (amphotericin B, itraconazole, terbinafine). Eighteen strains of species were used. The antifungal susceptibility assay was performed using the broth microdilution method. Mature biofilms were exposed to statins and metabolic activity was measured by the XTT reduction assay. MICs of statins ranged from 8 to 512 μg ml and from 8 to 256 μg ml for filamentous and yeast forms, respectively. Regarding mature biofilms, MICs of 50 % inhibition (SMIC50) were 128 μg ml for simvastatin and atorvastatin and >2048 μg ml for pravastatin. MICs of 90 % inhibition (SMIC90) were 512 μg ml for simvastatin and >2048 μg ml for atorvastatin and pravastatin.. These results highlight the antifungal and antibiofilm potential of statins against complex species.
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http://dx.doi.org/10.1099/jmm.0.001195DOI Listing
June 2020

Seroepidemiological survey on sporotrichosis-infection in rural areas of the south of Minas Gerais State, Brazil.

Braz J Microbiol 2021 Mar 13;52(1):41-47. Epub 2020 May 13.

Departamento de Microbiologia e Imunologia, Instituto de Ciências Biomédicas, Universidade Federal de Alfenas, Rua Gabriel Monteiro da Silva, 700 - Centro, Alfenas, Minas Gerais, 37130-001, Brazil.

Sporotrichosis is a subcutaneous mycosis caused by traumatic inoculation into the skin by fungi species of the genus Sporothrix. The disease has different clinical manifestations (cutaneous, lymphocutaneous, and disseminated), and can also progress to a systemic infection. Despite having a worldwide distribution, sporotrichosis is most prevalent in tropical and subtropical countries. In Brazil, reports of the disease are higher frequent, where cases of the disease were found in Rio de Janeiro, Sao Paulo, Curitiba, Pernambuco, and Paraiba, among others. Certain groups of people may be more exposed to the causative agent of disease, such as residents of rural areas. Thus, this work aimed to carry out a seroepidemiological survey of the prevalence of sporotrichosis in four rural locations in the south of Minas Gerais State, Brazil. In this study, we used an indirect ELISA test in the survey on the prevalence of sporotrichosis. Data obtained in this study evaluated a population of 631 individuals and showed a prevalence of 44.69%. The distribution of seroprevalence of sporotrichosis with respect to age groups and gender showed no significant statistical difference. Thus, we found a high seroprevalence of sporotrichosis-infection in rural regions of southern Minas Gerais State, Brazil, with no difference in prevalence in relation to gender and age.
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http://dx.doi.org/10.1007/s42770-020-00279-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7966674PMC
March 2021

The threat of emerging and re-emerging pathogenic Sporothrix species.

Mycopathologia 2020 Oct 12;185(5):813-842. Epub 2020 Feb 12.

Laboratory of Emerging Fungal Pathogens, Cell Biology Division, Department of Microbiology, Immunology and Parasitology, Paulista School of Medicine, Federal University of São Paulo, São Paulo, 04023-062, Brazil.

Sporotrichosis is a neglected subcutaneous mycosis of humans and animals acquired by traumatic inoculation of soil and plant material (classical route) contaminated with infectious propagules of the pathogen or being bitten/scratched by infected cats (alternative route). Within a genus composed of 53 species displaying an essentially environmental core, there are only a few members which have considerable impacts on human or animal health. Infections are typically caused by S. brasiliensis, S. schenckii or S. globosa. Rare mammal pathogens include members of the S. pallida and S. stenocereus complexes. To illustrate the tremendous impact of emerging zoonotic sporotrichosis on public health, we discuss the main features of the expanding epidemics driven by S. brasiliensis in cats and humans. The cat entry in the transmission chain of sporotrichosis, causing epizooties (cat-cat) or zoonosis (cat-human), has contributed to the definition of new paradigms in Sporothrix transmission, reaching epidemic levels, making the disease a serious public health problem. Indeed, S. brasiliensis infection in humans and animals is likely to become even more important in the future, with projections of its expansion in biogeographic domains and host range, as well as greater virulence in mammals. Therefore, lessons from a long-standing outbreak in the state of Rio de Janeiro about the source and distribution of the etiological agents among outbreak areas can be used to create better control and prevention plans and increase awareness of sporotrichosis as a serious emerging zoonotic disease.
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http://dx.doi.org/10.1007/s11046-020-00425-0DOI Listing
October 2020

First report of Paracoccidioides brasiliensis infection in fish.

Med Mycol 2020 Aug;58(6):737-743

Departamento de Ciências Patológicas, Centro de Ciências Biológicas, Universidade Estadual de Londrina, PR 445 Km 380, Londrina, Paraná, Brazil.

The thermodimorphic fungus Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis (PCM), a deep mycosis endemic in Latin American countries that affects mainly male rural workers. Infection by P. brasiliensis has also been reported in several species of terrestrial animals; however, the capacity of the fungus to infect aquatic organisms is poorly known. The aim of this study was to detect P. brasiliensis in a fish species, Nile tilapia (Oreochromis niloticus), the most farmed and widely distributed fish in endemic areas for human PCM in Brazil. As a first step, the humoral immune response against the fungus was evaluated in an experimental group of three fish immunized with inactivated P. brasiliensis yeast cells. For the seroepidemiological study, serum samples of Nile tilapia raised in cages (n = 109) and in ponds (n = 105), collected from a fish slaughterhouse, were analyzed for P. brasiliensis antibodies by ELISA using gp43 as antigen. All the inoculated fish produced antibodies against the fungus. The seropositivity observed in fish raised in cages and ponds was 17.4 and 5.7%, respectively. Due to the higher seropositivity observed in caged fish, 100 tissue samples (encephalon, liver, and kidney), from another group of tilapia raised in cages, were analyzed by polymerase chain reaction (PCR; Pb-ITSR and Pb-ITSE). Three tissue samples (liver n = 1, kidney n = 1, and enchepahlon n = 1) from three different fish resulted positive to PCR. This is the first report to show serological and molecular evidence of P. brasiliensis infection in a fish species.
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http://dx.doi.org/10.1093/mmy/myz120DOI Listing
August 2020

Evaluation of (1 → 3)-β-D-glucan assay for diagnosing paracoccidioidomycosis.

Mycoses 2020 Jan 5;63(1):38-42. Epub 2019 Nov 5.

Laboratório Especial de Micologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil.

Background: Paracoccidioidomycosis (PCM) is highly prevalent in Latin America, but no commercial system is available for diagnosing this endemic mycosis.

Objectives: To check the performance of (1 → 3)-β-D-glucan assay (BDG) for diagnosing  PCM in 29 patients with proven fungal disease and compared with double immunodiffusion assay for detecting anti-Paracoccidioides antibodies.

Patients And Methods: We selected 52 serum samples sequentially obtained from 29 patients with active PCM (12 chronic and 17 acute form). Samples were collected at baseline, and for 16 patients, additional serum levels were obtained after 3 and 6 months of antifungal treatment. Detection of BDG in serum was performed by using the Fungitell assay. For the double immunodiffusion assay, Paracoccidioides exoantigen was used in latex agglutination tests to detect serum anti-Paracoccidioides antibodies.

Results: Despite exhibiting good sensitivity in the diagnosis of patients with PCM, we failed to demonstrate any correlation between the postdiagnosis kinetic profile of BDG serum levels and clinical response to antifungal therapy. This finding may be related to the maintenance of quiescent foci of fungal infection in several organs and tissues, a phenomenon that has been previously reported by other authors and helps to understand why so many relapses are documented in patients treated for short periods of time. Finally, we did not find any correlation between BDG quantification and specific anti-P brasiliensis antibodies serum titres in patients with PCM.

Conclusions: In conclusion, BDG is detected in serum samples of most patients with PCM but is probably not useful for predicting clinical response to antifungal therapy.
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http://dx.doi.org/10.1111/myc.13007DOI Listing
January 2020

Proteomic analysis of Paracoccidioides brasiliensis complex isolates: Correlation of the levels of differentially expressed proteins with in vivo virulence.

PLoS One 2019 2;14(7):e0218013. Epub 2019 Jul 2.

Department of Microbiology, Immunology and Parasitology, Discipline of Cellular Biology, Federal University of São Paulo (UNIFESP), São Paulo, Brazil.

Background: Paracoccidioidomycosis (PCM) is a systemic mycosis commonly found in Latin America that is caused by distinct species of Paracoccidioides genus: Paracoccidioides brasiliensis complex (S1, PS2, PS3 and PS4) and Paracoccidioides lutzii. Its pathobiology has been recently explored by different approaches to clarify the mechanisms of host-pathogen interactions underpinning PCM. The diversity of clinical forms of this disease has been attributed to both host- and fungus-related factors.

Methodology/principal Findings: For better understanding of the molecular underpinnings of host-fungus interactions, we evaluated in vivo virulence of nine Paracoccidioides brasiliensis complex isolates and correlated it to protein expression profiles obtained by two-dimensional gel electrophoresis. Based on the recovery of viable fungi from mouse organs, the isolates were classified as those having low, moderate, or high virulence. Highly virulent isolates overexpressed proteins related to adhesion process and stress response, probably indicating important roles of those fungal proteins in regulating the colonization capacity, survival, and ability to escape host immune system reaction. Moreover, highly virulent isolates exhibited enhanced expression of glycolytic pathway enzymes concomitantly with repressed expression of succinyl-CoA ligase beta chain, a protein related to the tricarboxylic acid cycle.

Conclusions/significance: Our findings may point to the mechanisms used by highly virulent P. brasiliensis isolates to withstand host immune reactions and to adapt to transient iron availability as strategies to survive and overcome stress conditions inside the host.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0218013PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6605636PMC
February 2020

Clinical and epidemiological features of paracoccidioidomycosis due to Paracoccidioides lutzii.

PLoS Negl Trop Dis 2019 06 4;13(6):e0007437. Epub 2019 Jun 4.

Federal University of São Paulo, Paulista School of Medicine, Department of Microbiology, Immunology and Parasitology, Cellular Biology Division, São Paulo, São Paulo, Brazil.

Background: The fungus Paracoccidioides lutzii was recently included as a new causative species of paracoccidioidomycosis (PCM) and most cases have been reported from Brazil. According to available epidemiological information, P. lutzii is concentrated in the Middle-West region in Brazil, mainly in the state of Mato Grosso. However, clinical and laboratorial data available on patients infected with P. lutzii remain extremely limited.

Methodology/main Findings: This work describes the clinical manifestations of 34 patients suffering from PCM caused by P. lutzii, treated along 5 years (2011-2017) at a reference service center for systemic mycoses in Mato Grosso, Brazil. Adult rural workers (men), aged between 28 and 67 predominated. All patients had the chronic form of the disease, and the oral mucosa (n = 19; 55.9%), lymph nodes (n = 23; 67.7%), skin (n = 16; 47.1%) and lung (n = 28; 82.4%) were the most affected sites. Alcohol intake (n = 19; 55.9%) and smoking (n = 29; 85.3%) were frequent habits among the patients. No patient suffered from any other life-threatening disease, such as tuberculosis, cancer or other inflammatory or infectious parasitic diseases. The positivity in culture examination (97.1%) was higher than that found for the direct mycological examination (88.2%). Particularly, one patient presented fungemia at diagnosis, which lead to his death. The time elapsed between the initial symptoms and the initiation of treatment of PCM caused by P. lutzii was 19.7 (31.5) months, with most patients diagnosed 7 months after the symptoms' onset.

Conclusions/significance: Compared with the classical clinical-epidemiological profile of PCM caused by P. brasiliensis, the results of this descriptive study did not show significant clinical or epidemiological differences that could be attributed to the species P. lutzii. Future studies may confirm or refute the existence of clinical differences between the two fungal species.
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http://dx.doi.org/10.1371/journal.pntd.0007437DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6548353PMC
June 2019

Sodium butyrate inhibits planktonic cells and biofilms of Trichosporon spp.

Microb Pathog 2019 May 14;130:219-225. Epub 2019 Mar 14.

Department of Pathology and Legal Medicine, School of Medicine, Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Federal University of Ceará, Fortaleza-CE, Brazil; School of Veterinary, Postgraduate Program in Veterinary Science, State University of Ceará, Fortaleza-CE, Brazil.

Trichosporon spp. have been increasingly recognized as an important pathogen of invasive and disseminated infections in immunocompromised patients. These species are prone to form biofilms in medical devices such as catheters and prosthesis, which are associated with antifungal resistance and therapeutic failure. Therefore, new antifungals with a broader anti-biofilm activity need to be discovered. In the present study we evaluate the inhibitory potential of sodium butyrate (NaBut) - a histone deacetylase inhibitor that can alter chromatin conformation - against planktonic and sessile cells of T. asahii and T. inkin. Minimum inhibitory concentration (MIC) of NaBut against planktonic cells was evaluated by microdilution and morphological changes were analyzed by optical microscopy on malt agar supplemented with NaBut. Biofilms were evaluated during adhesion, development and after maturation for metabolic activity and biomass, as well as regarding ultrastructure by scanning electron microscopy and confocal laser scanning microscopy. NaBut inhibited the growth of planktonic cells by 50% at 60 mM or 120 mM (p < 0.05) and also reduced filamentation of Trichosporon spp. NaBut reduced adhesion of Trichosporon cells by 45% (10xMIC) on average (p < 0.05). During biofilm development, NatBut (10xMIC) reduced metabolic activity and biomass up to 63% and 81%, respectively (p < 0.05). Mature biofilms were affected by NaBut (10xMIC), showing reduction of metabolic activity and biomass of approximately 48% and 77%, respectively (p < 0.05). Ultrastructure analysis showed that NaBut (MIC and 10xMIC) was able to disassemble mature biofilms. The present study describes the antifungal and anti-biofilm potential of NaBut against these opportunist emerging fungi.
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http://dx.doi.org/10.1016/j.micpath.2019.03.013DOI Listing
May 2019

Correction to: Effects of metaperiodate and urea solutions on the serological diagnosis of human sporotrichosis using an indirect ELISA test.

Braz J Microbiol 2019 04;50(2):579

Departamento de Microbiologia e Imunologia, Instituto de Ciências Biomédicas, Universidade Federal de Alfenas, Rua Gabriel Monteiro da Silva, 700 - Centro, Alfenas, MG, CEP 37130-001, Brazil.

In the article mentioned above an author's name was misspelled. The correct author name reads as follows: Leila Maria Lopes-Bezerra. We apologize for the inconvenience.
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http://dx.doi.org/10.1007/s42770-019-00070-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6863336PMC
April 2019

Effects of metaperiodate and urea solutions on the serological diagnosis of human sporotrichosis using an indirect ELISA test.

Braz J Microbiol 2019 01 13;50(1):139-145. Epub 2018 Dec 13.

Departamento de Microbiologia e Imunologia, Instituto de Ciências Biomédicas, Universidade Federal de Alfenas, Rua Gabriel Monteiro da Silva, 700 - Centro, Alfenas, MG, CEP 37130-001, Brazil.

Sporotrichosis is an infection of the skin caused by traumatic inoculation of the fungus Sporothrix schenckii. Definitive diagnosis relies on direct visualization of the fungus or its isolation on culture medium, although both have low sensitivity. Alternatively, the detection of the antibody response offers a more rapid alternative for diagnosis. Although the available immunoassays possess good sensitivity and specificity, cross-reactivity is still a problem. This study aimed to evaluate the effect of sodium metaperiodate and 6 M urea solutions on the serological diagnosis of sporotrichosis using an enzyme-linked immunosorbent assay (ELISA) test. Ninety-six-well plates were sensitized with exoantigens from the yeast phase of S. schenckii. Sera of patients with confirmed sporotrichosis, sera of patients with paracoccidioidomycosis, and sera of individuals with a sporotrichin-negative skin test were tested. Two strategies were used; the first consisted of treating the antigen with sodium metaperiodate solution for different incubation times, and the second consisted of treating the serum with 6 M urea solution for different incubation times. ROC curve analysis revealed that the best discrimination parameters were obtained using 6 M urea solution incubated for 5 min and serum dilution at 1/600. The use of 6 M urea solution improves the performance of the ELISA test in the diagnosis of sporotrichosis.
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http://dx.doi.org/10.1007/s42770-018-0005-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6863317PMC
January 2019

Potassium iodide and miltefosine inhibit biofilms of Sporothrix schenckii species complex in yeast and filamentous forms.

Med Mycol 2019 Aug;57(6):764-772

Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Department of Pathology and Legal Medicine, Federal University of Ceará, Fortaleza, CE, Brazil.

This study aimed to evaluate the yeast biofilm growth kinetics and ultrastructure of Sporothrix schenckii complex and assess their mature biofilm susceptibility in filamentous and yeast forms to potassium iodide (KI) and miltefosine (MIL). Yeast biofilms were evaluated by crystal violet staining, XTT reduction assay and microscopic techniques. Susceptibility of planktonic and sessile cells was analyzed by broth microdilution. S. schenckii complex in yeast form produced biofilms, with an optimum maturation at 96 h, showing multilayered blastoconidia embedded in extracellular matrix. KI and MIL minimum inhibitory concentration (MIC) ranges against planktonic cells were 62,500-250,000 μg/ml and 0.125-4 μg/ml, respectively. KI and MIL reduced biofilm metabolic activity by 75.4% and 67.7% for filamentous form and 55.1% and 51.6% for yeast form, respectively. This study demonstrated that S. schenckii complex forms biofilms in vitro, and potassium iodide and miltefosine inhibit Sporothrix spp. biofilms in both filamentous and yeast forms.
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http://dx.doi.org/10.1093/mmy/myy119DOI Listing
August 2019

[Brazilian guidelines for the clinical management of paracoccidioidomycosis].

Epidemiol Serv Saude 2018 08 16;27(spe):e0500001. Epub 2018 Aug 16.

Universidade de São Paulo, Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, SP, Brasil.

Paracoccidioidomycosis is a systemic fungal disease associated with agricultural activities. Its incidence and prevalence are underestimated because of the lack of reporting in several Brazilian states. If paracoccidiodomycosis is not diagnosed and treated early and adequately, endemic fungal infection may result in serious sequelae. In addition to the Paracoccidioides brasiliensis (P. brasiliensis) complex, the appearance of a new species, Paracoccidioides lutzii (P. lutzii), in Rondônia state, where the disease has reached epidemic levels, and in the country's Midwest region and Pará state, are challenges to diagnosis and to the urgent availability of antigens that are reactive with patients' sera. These guidelines aim to update the first Brazilian consensus on paracoccidioidomycosis by providing evidence-based recommendations for bedside patient management. The guidelines provide data on etiology, epidemiology, immunopathogenesis, diagnosis, treatment and sequelae, with emphasis on diagnosis and treatment, as well as current recommendations and challenges in this field of knowledge.
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http://dx.doi.org/10.5123/S1679-49742018000500001DOI Listing
August 2018

Inhibitory effect of a lipopeptide biosurfactant produced by Bacillus subtilis on planktonic and sessile cells of Trichosporon spp.

Biofouling 2018 03 21;34(3):309-319. Epub 2018 Mar 21.

a Department of Pathology and Legal Medicine , Federal University of Ceará , Fortaleza , Brazil.

The present study aimed to investigate the inhibitory effect of a bacterial biosurfactant (TIM96) on clinical strains of Trichosporon. Additionally, the effect of TIM96 on the ergosterol content, cell membrane integrity, and the hydrophobicity of planktonic cells was assessed. The inhibitory activity of TIM96 against Trichosporon biofilms was evaluated by analyzing metabolic activity, biomass and morphology. MIC values ranged from 78.125 to 312.5 μg ml for TIM96; time-kill curves revealed that the decline in the number of fungal cells started after incubation for 6 h with TIM96 at both MIC and 2×MIC. The biosurfactant reduced the cellular ergosterol content and altered the membrane permeability and the surface hydrophobicity of planktonic cells. Incubation at 10×MIC TIM96 reduced cell adhesion by up to 96.89%, thus interfering with biofilm formation. This concentration also caused up to a 99.2% reduction in the metabolic activity of mature biofilms. The results indicate potential perspectives for the development of new antifungal strategies.
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http://dx.doi.org/10.1080/08927014.2018.1437617DOI Listing
March 2018

Sporotrichosis between 1898 and 2017: The evolution of knowledge on a changeable disease and on emerging etiological agents.

Med Mycol 2018 Apr;56(suppl_1):126-143

Westerdijk Fungal Biodiversity Institute, Utrecht, and Center of Expertise in Mycology of Radboudumc/CWZ, Nijmegen, The Netherlands.

The description of cryptic species with different pathogenic potentials has changed the perspectives on sporotrichosis. Sporothrix schenckii causes a benign chronic subcutaneous mycosis, Sporothrix brasiliensis is highly virulent, and Sporothrix globosa mainly causes fixed cutaneous lesions. Furthermore, S. brasiliensis is the prevalent species related to cat-transmitted sporotrichosis. Sources of infection, transmission, and distribution patterns also differ between species, and variability differs between species because of different degrees of clonality. The present review article will cover several aspects of the biology of clinically relevant agents of sporotrichosis, including epidemiological aspects of emerging species. Genomic information of Sporothrix spp. is also discussed. The cell wall is an essential structure for cell viability, interaction with the environment, and the host immune cells and contains several macromolecules involved in virulence. Due to its importance, aspects of glycosylation and cell wall polysaccharides are reviewed. Recent genome data and bioinformatics analyses helped to identify specific enzymes of the biosynthetic glycosylation routes, with no homologs in mammalian cells, which can be putative targets for development of antifungal drugs. A diversity of molecular techniques is available for the recognition of the clinically relevant species of Sporothrix. Furthermore, antigens identified as diagnostic markers and putative vaccine candidates are described. Cell-mediated immunity plays a key role in controlling infection, but Sporothrix species differ in their interaction with the host. The adaptive branch of the immune response is essential for appropriate control of infection.
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http://dx.doi.org/10.1093/mmy/myx103DOI Listing
April 2018

Corrigendum: Clotrimazole is highly effective in vitro against feline Sporothrix brasiliensis isolates.

J Med Microbiol 2018 03;67(3):463

Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.

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http://dx.doi.org/10.1099/jmm.0.000701DOI Listing
March 2018

Clotrimazole is highly effective in vitro against feline Sporothrix brasiliensis isolates.

J Med Microbiol 2017 Nov 6;66(11):1573-1580. Epub 2017 Oct 6.

Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.

Purpose: Sporothrix brasiliensis, the most virulent species in the Sporothrix schenckii complex, is responsible for the ongoing epidemics of human and animal sporotrichosis in Brazil. Feline outbreaks are usually driven by S. brasiliensis and followed by extensive transmission to humans. Itraconazole is the first-line treatment for both feline and human sporotrichosis; however, reduced sensitivity is an emerging issue. Thus, we investigated the effect of the widely used antifungal clotrimazole - alone or in combination with itraconazole - against the pathogenic (yeast) form of feline and human S. brasiliensis isolates, in vitro.

Methodology: Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values were determined for treatment with clotrimazole and itraconazole, as monotherapy or in combination. In addition, the effect of the drugs on neutral lipid levels and the yeast ultrastructure were evaluated by flow cytometry and transmission electron microscopy (TEM), respectively.

Results: The MIC and MFC values show that clotrimazole was more effective than itraconazole against feline S. brasiliensis isolates, while human isolates were more sensitive to itraconazole. Similarly to itraconazole, treatment with clotrimazole induced statistically significant neutral lipid accumulation in S. brasiliensis yeasts, and treated yeasts displayed irregularities in the cell membrane and a thicker cell wall when observed by TEM. Clotrimazole increased the antifungal activity of itraconazole in combination assays, with a synergistic effect for two feline isolates.

Conclusion: The strong activity of clotrimazole against feline S. brasiliensis isolates suggests that this drug is potentially a new alternative for the treatment of feline sporotrichosis, alone or in combination with itraconazole.
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http://dx.doi.org/10.1099/jmm.0.000608DOI Listing
November 2017

The HIV aspartyl protease inhibitor ritonavir impairs planktonic growth, biofilm formation and proteolytic activity in Trichosporon spp.

Biofouling 2017 09;33(8):640-650

a Medical Mycology Specialized Center , Federal University of Ceará , Fortaleza , Brazil.

This study evaluated the effect of the protease inhibitor ritonavir (RIT) on Trichosporon asahii and Trichosporon inkin. Susceptibility to RIT was assessed by the broth microdilution assay and the effect of RIT on protease activity was evaluated using azoalbumin as substrate. RIT was tested for its anti-biofilm properties and RIT-treated biofilms were assessed regarding protease activity, ultrastructure and matrix composition. In addition, antifungal susceptibility, surface hydrophobicity and biofilm formation were evaluated after pre-incubation of planktonic cells with RIT for 15 days. RIT (200 μg ml) inhibited Trichosporon growth. RIT (100 μg ml) also reduced protease activity of planktonic and biofilm cells, decreased cell adhesion and biofilm formation, and altered the structure of the biofilm and the protein composition of the biofilm matrix. Pre-incubation with RIT (100 μg ml) increased the susceptibility to amphotericin B, and reduced surface hydrophobicity and cell adhesion. These results highlight the importance of proteases as promising therapeutic targets and reinforce the antifungal potential of protease inhibitors.
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http://dx.doi.org/10.1080/08927014.2017.1350947DOI Listing
September 2017
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