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We evaluated the growth and the susceptibility to oxidative stress of Sporothrix spp., exposed to different iron concentrations in culture medium, and the susceptibility of Sporothrix spp. to itraconazole, alone and in combination with to the iron chelator deferasirox. The results showed that the growth of S. brasiliensis isolates was more affected by iron availability in comparison to S. schenckii, but both fungal species conidia became more prone to oxidative stress when iron was added to culture medium. Conversely, the combination of itraconazole and deferasirox only resulted in synergism against a minority of S. schenckii isolates.

The present study reports a new occurrence of Rhinocladiella similis isolated as an endophytic fungus in the Caatinga dry tropical forest in Brazil and describes its antifungal susceptibility. The isolate R. similis URM 7800 was obtained from leaves of the medicinal plant Myracrodruon urundeuva. Its morphological characterization was performed on potato dextrose agar medium and molecular analysis using the ITS rDNA sequence. The antifungal susceptibility profile was defined using the Clinical and Laboratory Standards Institute (CLSI) protocol M38-A2. The colony of isolate URM 7800 showed slow growth, with an olivaceous-gray color and powdery mycelium; in microculture, it showed the typical features of R. similis. In the antifungal susceptibility test, isolate URM 7800 showed high minimal inhibitory concentration (MIC) values for amphotericin B (16 μg/mL), voriconazole (16 μg/mL), terbinafine (0.5 μg/mL), and caspofungin (8 μg/mL), among other antifungal drugs. Pathogenic melanized fungi are frequently isolated in environments where humans may be exposed, and these data show that it is essential to know if these isolates possess antifungal resistance.

Four yeast isolates with an affinity to the genus Wickerhamiella were obtained from beach sand, a marine zoanthid and a tree exudate at different localities in Brazil. Two other isolates with almost identical ITS and D1/D2 sequences of the large subunit rRNA gene were isolated from the small intestine of cattle and a grease trap in Thailand. These isolates represent a novel species phylogenetically related to Wickerhamiella verensis, Wickerhamiella osmotolerans, Wickerhamiella tropicalis, Wickerhamiella sorbophila and Wickerhamiella infanticola. The novel species differs by 15–30 nucleotide differences from these species in the D1/D2 sequences. The name Wickerhamiella martinezcruziae f.a., sp. nov. is proposed. The holotype of Wickerhamiella martinezcruziae sp. nov. is CBS 16104T. The MycoBank number is MB 839328.

Syphilis is a chronic bacterial sexually transmitted infectious disease caused by Treponema pallidum. Different age groups are affected by heterogeneous clinical forms of the disease. We report a case of atypical secondary syphilis in an elderly patient with diffuse annular erythematous lesions on the chest, back, upper and lower limbs diagnosed by histopathological, immunohistochemical and serological tests.

We report a case of a 56-year-old Brazilian woman, with relapsing lepromatous leprosy, and onychomycosis caused by a non-dermatophyte filamentous fungi. The pathogenic fungi was identified as Arthrinium arundinis and treated with chemical abrasion of the nail with 40% urea and application of terbinafine cream. Onychomycosis caused by Arthrinium species is rare, and this is the second reported case.

Background Sporotrichosis is a group of zoonotic subcutaneous mycoses, found worldwide and caused by fungi belonging to the genus Sporothrix. Protozoans of the genus Acanthamoeba are widely distributed, and some species may be pathogenic and/or opportunistic. These organisms coexist in the same environment and may interact. Objectives This study determined the profile of interactions of S schenckii sensu stricto and S brasiliensis with A castellanii, using an in vitro co-culture model to evaluate the intrinsic characteristics of the two Sporothrix species and A castellanii. Methods We compared the rate of phagocytosis of S schenckii sensu stricto and S brasiliensis by A castellanii; the viability of S schenckii sensu stricto and S brasiliensis after contact with A castellanii; the viability of the amoeba after contact with a fungal species; and the influence of S schenckii sensu stricto and S brasiliensis on the encystment process of A castellanii. Results The analyses indicated that A castellanii phagocytised both S schenckii and S brasiliensis, with significantly more S schenckii than S brasiliensis in the first two hours of contact. Our results showed a significant increase in conidia and hyphae count after 72 hours of co-culture of A castellanii with S brasiliensis, and the amoebae lysed after they ingested the fungi, indicating that the fungi probably used the amoebae as a source of nutrition. Conclusions Our results were obtained in vitro and these organisms may not behave similarly in vivo; in vivo studies of co-infections are necessary in order to gain a thorough understanding of this relationship.

Background Dermatophytoses affect more than 20% of the world's population and is caused by filamentous fungi, mainly of the genus Trichophyton. The species identification through microscopic direct examination and culture methods is challenging, with molecular presenting high sensitivity and specificity. Although there are several therapy options for dermatophyte infections, treatment failures and antifungal resistance are growing concerns. Objective This study aimed to identify clinical isolates of Trichophyton spp. from southern Brazil using molecular methods and determine their in-vitro antifungal susceptibility. Material and Methods Seventy-five isolates were identified through sequencing of the ITS region. The exposure to seven antifungals drugs was performed according to protocol M28-A2 of the Clinical and Laboratory Standards Institute (CLSI). Results Sixty-one isolates (81%) were identified as T. interdigitale, which differs from the epidemiological data present in the literature. Thirteen isolates were identified as T. rubrum and one as T. tonsurans. Terbinafine was the most effective antifungal, followed by itraconazole and voriconazole, which is in accordance with the results reported in previous studies. Conclusions The use of molecular methods to identify Trichophyton spp. clinical isolates and the performance of susceptibility tests are relevant to epidemiological data, identification of the emergence of antifungal resistance, and to help to translate the in-vitro antifungal susceptibility results into clinical practice.

Chromoblastomycosis (CBM) is a chronic subcutaneous infection caused by genera of melanized fungi: Fonsecaea, Cladophialophora, Phialophora, Exophiala, and Rhinocladiella. Melanin is a virulence factor known to influence antifungal susceptibility. A specific inhibitor of melanin biosynthesis is tricyclazole. The aim of this study was to evaluate the effect of melanin inhibition on antifungal susceptibility of chromoblastomycosis agents and describe the susceptibility profiles of some unusual CBM agents. Seventy-six clinical isolates, representing 13 species of the five main genera of CBM agents, were studied. The antifungal susceptibility testing was performed according to the M38-A2 protocol of CLSI (Reference Method for Broth Dilution Antifungal Susceptibility Testing of Filamentous Fungi, 3rd ed., CLSI Standard M38, 2017). In the melanin inhibition test, 16 mg/liter of tricyclazole was added to the medium used in the inoculum preparation and the susceptibility assay. CBM agents were less susceptible to amphotericin B than azoles and terbinafine. The unusual species showed similar susceptibility profiles to those of other species of the same genera. With tricyclazole exposure, MICs of terbinafine, posaconazole, and itraconazole for Fonsecaea spp. significantly decreased (P < 0.05). For Phialophora spp., this reduction was significant for posaconazole and itraconazole. For the other genera, there was a reduction in MICs of terbinafine and itraconazole; however, the statistical tests were not significant. Melanin inhibition can increase the antifungal susceptibility of most CBM agents to itraconazole and terbinafine, the main drugs used in the disease treatment. This increased susceptibility may open up new possibilities for therapy in refractory cases of CBM and/or cases caused by resistant fungal strains. Further studies are needed to confirm the same results in vivo.

Not applicable

Chromoblastomycosis (CBM) is a skin and subcutaneous infection caused by species of seven fungal genera. Identification of CBM species is performed by DNA sequencing of one or more genes, which becomes a time-consuming work. Fourier Transform Infrared Spectroscopy (FTIR) has been used for the identification of other microorganisms, however, only one CBM genus was evaluated by FTIR analysis to date. Therefore, the study is aimed to differentiate the CBM agents for identification at genera level using FTIR supervised by Internal Transcribed Spacer (ITS) rDNA region. Seventy-seven isolates of the main five CBM genera were prepared for Attenuated Total Reflection FTIR (ATR-FTIR) with a new methodology using slices of dry fungus in glass fixing-modeling proposed in this study. The algorithm Hierarchical Cluster Analysis (HCA) was used to analyze the differences and similarities between species through the spectra. Orthogonal Partial Least Square Discriminant Analysis (OPLS-DA) allowed to correctly classify all samples of five CBM genera. The ATR-FTIR/OPLS-DA models highlighted important contributions of regions attributed to NH and OH stretching, amide I of proteins, polysaccharides bands and fingerprint region for the complete differentiation of the genera investigated. Thus, FTIR can be a fast and inexpensive alternative for identification of CBM agents.

Melanins are a diverse group of dark pigments with similar properties. In fungi, the most studied is the dihydroxynaphtalene (DHN)-melanin, present in several species including all the chromoblastomycosis agents, a chronic, disabling, and recalcitrant subcutaneous mycosis. It is synthesized in a pathway known as the pentaketide pathway, which has the agrochemical tricyclazole as an inhibitor, widely used in in vitro studies because it does not prevent the growth of fungi. There are different methodologies for qualitative and quantitative analyses of DHN-melanin, which made it possible to discover its important structural and antioxidant functions, with melanin acting as a protective factor against the host's immune system. Also, it can interact with some of the main antifungals of medical interest, reducing its activity and the susceptibility of fungi to these agents. This review aims to discuss the aspects of DHN-melanin, focusing on chromoblastomycosis, bringing the main findings of the published scientific studies, and highlighting the need for further research to understand this important fungal pathogenicity and a virulence factor.

One new yeast species, Papiliotrema maritimi sp. nov., is being proposed to be suitable into the Rhynchogastremataceae family, belonging to the Tremellales clade. This new species is related to six others from the Papiliotrema genus: P. taeanensis, P. siamense, P. perniciosus, P. nemorosus, P. bandonii, P. japonica and P. fuscus. The novel species is proposed based on the phylogenetic species concept through analysis of the D1/D2 region, part of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region. A total of 11 strains of Papiliotrema maritimi sp. nov. were obtained from macrophytes leaves collected in south Brazil. Papiliotrema maritimi sp. nov. differs by 12, 15, 25, 25, 25 and 29 substitutions in the D1/D2 domain from the related species P. fuscus, P. japonica, P. siamense, P. nemorosus, P. bandonii, and P. perniciosus, respectively. Concerning the ITS region, there are 11 substitutions and 52 or more substitutions when compared to P. teanensis and its closest relatives. The type strain of Papiliotrema maritimi sp. nov. is UFMG-CM-Y6048. The MycoBank number for Papiliotrema maritimi sp. nov. is MB 835603.

We report a case of phaeohyphomycosis that affected the leg of a 45-year-old Brazilian man, car mechanic and renal transplanted. The direct mycological examination evidenced dematiaceous septated hyphae. The pathogenic fungal species was identified as Exophiala xenobiotica. Antifungal activity in vitro revealed terbinafine as the best antifungal. For treatment, it was chosen surgical excision of the entire lesion and used systemic itraconazole. Phaeohyphomycosis caused by Exophiala xenobiotica is extremely rare and is closely related to transplant patients. Keywords: Exophiala xenobiotica, Phaeohyphomycosis, Immunosuppressed, Renal transplantation

We report a case of a patient with lymphocutaneous sporotrichosis in the right upper limb. The fungus was identified as Sporothrix schenckii senso stricto by calmodulin gene sequencing. The initial treatment was itraconazole (200 mg/day), but in vitro antifungal susceptibility demonstrated high resistant to this and another six antifungals, with exception to terbinafine. The lesions did not regress with itraconazole treatment. Thus, 500 mg/day of terbinafine was prescribed and clinical cure was obtained after four months

The stored food mite Tyrophagus putrescentiae (Schrank) (Acari: Acaridae) has been associated with the presence of several fungal species. The aims of this work were to evaluate T. putrescentiae population growth associated to environmental and medically important fungal species to determine on which fungal species populations of T. putrescentiae performs best, and to evaluate their ability to disperse each fungal species. First, 24 fungal species were inoculated separately in Petri dishes containing Sabouraud agar medium. One week after inoculation, 50 mites were added to each plate. On the 28th evaluation day, mites and eggs were counted in each plate, and 50 mites randomly collected from each replicate were transferred to new plates containing only Sabouraud agar medium. Then, mites, eggs, and fungal population were evaluated in each plate on day 28 again. The highest population increases were on Trichophyton mentagrophytes, Alternaria sp., Microsporum gypseum, and Aspergillus chevalieri. With Fusarium guttiforme and the medically important fungi Microsporum canis, M. gypseum, T. mentagrophytes, and Sporothrix sp., mites were observed to feed on whole mycelium. Only eight fungal species were dispersed by T. putrescentiae to the new Petri dishes: Aspergillus clavatus, Candida tropicalis, Candida albicans, Fusarium guttiforme, Hyphopichia burtonii, Penicillium citrinum, Rhizophus azygosporus, and Trichophyton mentagrophytes. The best performance of T. putrescentiae was found feeding on F. guttiforme, P. citrinum, and T. mentagrophytes. In conclusion, T. putrescentiae successfully used fungi as a food source, and it proved to be an important tool for disseminating both environmental and medically important fungi.

We report a case of chromoblastomycosis in lesions on the chest and foot. Itraconazole was chosen as the initial treatment for this patient, who was followed up for 8 months before becoming noncompliant. The pathogenic fungal species was identified as Rhinocladiella similis by ITS region sequencing. In vitro analyses indicate that the fungus was sensitive to posaconazole and itraconazole. This report presents R. similis as a new agent of chromoblastomycosis and raises the hypothesis that this species could be more resistant to some antifungals than R. aquaspersa.

The eugenol is the active ingredient of clove oil and it has shown to be effective and safe as fish anesthetic. In this study were evaluated the effects of different concentrations of eugenol for anesthesia, recovery time, blood glucose and hematocrit percentage of pearl cichlid (Geophagus brasiliensis) juveniles. Concentrations of 50, 80, 100, 120, 150, 170 and 200 mg L-1 eugenol were evaluated in terms of time to achieve the different stages of anesthesia and recovery in a completely randomized design (CRD) with 12 repetitions. These results were tested using the Kruskal-Wallis test with subsequent Dunn test. The evaluated concentrations had anesthetic action of the deep induction 172.57 ± 25 s (50 mg L-1) and the period of full recovery of 516.25 ± 102 s (200 mg L-1), with statistical difference between the treatments at all the stages. The eugenol effect on blood glucose and on hematocrit percentage at 0 h after deep anesthesia was evaluated for concentrations of 0; 50; 80; 100; 150; 200 mg L-1, in a completely randomized design with five replications, and the results were assessed by One-Way ANOVA. Glucose and percentage of hematocrit: no statistically significant differences (P>0.05) were observed for these variables. All concentrations of eugenol showed to be effective as an anesthetic for G. brasiliensis and did not affect the survival, blood glucose and the percentage of hematocrit. To minimize adverse effects and achieve faster recovery is indicate the use of 50-80 mg L-1 of eugenol for pearl cichlid juveniles.

Two independent surveys of yeasts associated with different bromeliads in different Brazilian regions led to the proposal of a novel yeast species,Bullera vrieseaesp. nov., belonging to the Tremellales clade (Agaricomycotina, Basidiomycota). Analysis of the sequences in the internal transcribed spacer (ITS) region and D1/D2 domain of the LSU rRNA gene suggested affinity to a phylogenetic lineage that includesBullera miyagianaandBullera sakaeratica. Six isolates of the novel species were obtained from different bromeliads and regions in Brazil. Sequence analysis of the D1/D2 domains of the large subunit of the rRNA gene showed that the novel species differs fromB.miyagianaandB. sakaeraticaby 85 and 64 nt substitutions, respectively and by more than 75 nt substitutions in the ITS region. Phenotypically,Bullera vrieseaesp. nov. can be distinguished from both species based on the assimilation ofmeso-erythritol, which was negative forB. vrieseaesp. nov. but positive for the others, assimilation ofd-glucosamine, which was positive forB. vrieseaesp. nov. but negative forB. miyagianaand ofl-sorbose, which was negative forB. vrieseaesp. nov. but positive forB. sakaeratica. The novel speciesBullera vrieseaesp. nov. is proposed to accommodate these isolates. The type strain ofBullera vrieseaesp. nov. is UFMG-CM-Y379T(BRO443T; ex-type CBS 13870T).

We report a case of a patient with lymphocutaneous sporotrichosis in the right upper limb. The fungus was identified as Sporothrix schenckii senso stricto by calmodulin gene sequencing. The initial treatment was itraconazole (200 mg/day), but in vitro antifungal susceptibility demonstrated high resistant to this and another six antifungals, with exception to terbinafine. The lesions did not regress with itraconazole treatment. Thus, 500 mg/day of terbinafine was prescribed and clinical cure was obtained after four months

Candida is a common fungus with the capacity to cause infections in humans. However, most studies have concentrated on clinical isolates and little is known about the identity, ecology and drug resistance of free living species/strains. Here, we isolate eight strains of Candida haemulonii and four strains of Cutaneotrichosporon dermatis from three marine cnidarian zoanthids species (Palythoa caribaeorum, Palythoa variabilis and Zoanthus sociatus) collected from Brazilian coral reefs. Strains were identified by sequencing of the D1/D2 domain LSU rDNA and ITS region. We tested these environmental isolates for their capacity to grow in media with increasing concentration of NaCl, capacity to grow in different temperatures, enzymatic activity and antifungal susceptibility. For C. haemulonii, all strains strongly produced gelatinase, esterase and albuminase and were either able to express lipase, phospholipase and keratinase, but not express urease and DNase. The strains were able to grow at 37 °C, but not at 39 °C, and except for LMS 40, all of them could grow in a 10 % NaCl medium. All isolates were resistant to all antifungals tested, with exception for ketoconazole and tioconazole (MIC = 2 µg/mL). For C. dermatis, all strains could grow at 39 °C and could not express phospholipase, keratinase or gelatinase. However, all were capable of expressing urease, lipase and esterase. Three out of four strains could grow in a 10 % NaCl medium, but none grew in a 30 % NaCl medium. The strains showed high values of minimal inhibitory concentration. LMPV 90 was resistant to tioconazole, terbinafine, fluconazole and posaconazole, and LMS 38 was resistant to all antifungal agents tested. We discuss the characterization of C. haemulonii and C. dermatis as a possible emerging pathogen due to its animal-related enzymatic arsenal and antifungal resistance.

Two yeast species, Papiliotrema leoncinii sp. nov. and Papiliotrema miconiae sp. nov., in the family Rhynchogastremataceae of the Tremellales are proposed. The two species are related to six species of the genus Papiliotrema: Papiliotrema aureus, P. flavescens, P. terrestris, P. baii, P. ruineniae and P. wisconsinensis. The novel species are proposed on the basis of the sequence-based phylogenetic species concept with analysis of the D1/D2 region of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region. A total of 16 strains of Papiliotrema leoncinii sp. nov. were obtained from freshwater and bromeliad leaves collected in Brazil. Papiliotrema leoncinii sp. nov. differs by 11, 12, 16, 14, 11 and 13 substitutions in the D1/D2 domain from the related species P. aureus, P. flavescens, P. terrestris, P. baii, P. ruineniae and P. wisconsinensis, respectively. Differences of 11 substitutions and 21 or more substitutions in ITS regions were found when the sequences of Papiliotrema leoncinii sp. nov. were compared with P. wisconsinensis and its closest relatives. The type strain of Papiliotrema leoncinii sp. nov. is UFMG-CM-Y374T (=CBS 13918T). Papiliotrema miconiae sp. nov. is represented by two strains isolated from a flower of Miconia sp. and a water sample in Brazil. Papiliotrema miconiae sp. nov. differs from the related species P. aureus and P. ruineniae by eight substitutions, from P. flavescens and P. terrestris by 11 substitutions, from P. baii by 10 substitutions and from P. wisconsinensis by 6 substitutions in the D1/D2 domain, and by 7 substitutions from P. wisconsinensis and more than 19 substitutions in the ITS region from its closest relatives. The type strain of Papiliotrema miconiae sp. nov. is CBS 8358T (ML 3666T=DBVPG-4492T). The MycoBank numbers for Papiliotrema leoncinii sp. nov. and Papiliotrema miconiae sp. nov. are MB 813594 and MB 814882, respectively.

Four strains of Hortaea werneckii were isolated from different substrates in Brazil (a salt marsh macrophyte, a bromeliad and a marine zoanthid) and had their identification confirmed by sequencing of the 26S rDNA D1/D2 domain or ITS region. Most of the strains were able to express amylase, lipase, esterase, pectinase and/or cellulase, enzymes that recognize components of plant cells as substrates, but did not express albuminase, keratinase, phospholipase and DNAse, whose substrates are animal-related. Urease production was positive for all isolates, while caseinase, gelatinase and laccase production were variable among the strains. All the strains grew in media containing up to 30% NaCl. We propose that the primary substrate associated with H. werneckii is plant-related, in special in saline environments, where the fungus may live as a saprophyte and decomposer. Infection of animal-associated substrates would be secondary, with the fungus acting as an opportunistic animal pathogen. All strains were resistant to fluconazole and presented high MIC for amphotericin B, while they were susceptible to all the other antifungal agents tested.