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Introduction: Yacon (Smallanthus sonchifolius) is a functional food, rich in fructooligosaccharides, and has been widely used in scientific research, showing effects in reducing lipid and glycemic levels, in addition to having antibacterial, antioxidant and neuroprotective properties. The objective was to evaluate the hydroalcoholic extract of yacon leaf in Candida species. Methods: Thirty-three samples of different species of the genus Candida treated with yacon leaf extract at concentrations of 25 to 400ug/ml were analyzed using the Minimum Inhibitory Concentration method described by the M27-A3 protocol of the Clinical and Laboratory Standards Institute. Results: Among the species of C. albicans, 16 samples showed sensitivity to the extract at the concentrations used. Conclusion: Yeasts of the Candida genus are able to adapt to different environments due to their high degree of resistance to antifungal agents, making it increasingly necessary to use natural substances as alternatives for the treatment of diseases caused by fungi. The antifungal activity of yacon leaf extract against fungi of the genus Candida is being reported for the first time in this study, making yacon a new therapeutic alternative.

The emergence of resistant isolates has brought challenges to the treatment of sporotrichosis, prompting the search for new therapeutic strategies. Previous studies reported that nonsteroidal anti-inflammatory drugs (NSAIDs) show in vitro activity against several pathogenic fungi, including species of Candida, Cryptococcus, and Trichosporon.This study aimed to investigate the in vitro efficacy of three NSAIDs (acetylsalicylic acid, diclofenac sodium, and ibuprofen), alone and in combination with itraconazole, against eleven clinical isolates of Sporothrix brasiliensis and Sporothrix schenckii.Minimal inhibitory concentrations were determined by the broth microdilution method. Drug interactions and the fractional inhibitory concentration index of NSAIDs and itraconazole were assessed by the checkerboard method.When used alone, ibuprofen was the most active NSAID, followed by acetylsalicylic acid. Combinations of NSAIDs with itraconazole showed synergistic antifungal activity against nine isolates. It was also found that itraconazole combined with acetylsalicylic acid, diclofenac sodium, or ibuprofen, led to resistance reversal in two, three, and five of the six drug-resistant isolates, respectively.The results indicate that the combination of itraconazole and the evaluated NSAIDs are a promising strategy for the treatment of sporotrichosis.

Background: The use of peripheral intravenous devices can lead to infections and increase the length of hospital care worldwide in humans and animals. Antisepsis is indicated in several ambulatory and surgical procedures. Chlorhexidine is an antiseptic widely used in veterinary clinical practice. Nanoparticle solutions have been studied to improve antimicrobial effect. Therefore, we aimed to evaluate the antiseptic effect of chlorhexidine nanoemulsion at 0,25% (NM-Cl) in cat skin and to compare it with the chlorhexidine commercial solution at 2.0% (CS-Cl). After a wide trichotomy of the thoracic limbs, the skin antisepsis was performed with NM-Cl or CS-Cl and a catheter was inserted at the cephalic vein. Cutaneous microbiota swab samples (CMSS) were obtained before antisepsis (Tpre), immediately after antisepsis (Tpost), and four, eight, and 24 hours after antisepsis. The samples collected were immediately inoculated in blood agar plates and incubated at 35±2ºC in aerobiosis. The manual counting of the colony-forming unit (CFU) was performed 24 hours after inoculation. Kruskal–Wallis and Mann–Whitney tests were used between groups and inside the same group, at different sample times. Result: The NM-Cl and CS-Cl groups showed a reduction in the CFU between the Tpre and Tpost in all animals (p). Both formulations presented an antiseptic effect 24 hours after antisepsis (p<0.05), and there was no difference between formulations at the different times (p<0.05). Nonetheless, the NM-Cl carried a lowers concentration of chlorhexidine than CS-Cl. Conclusion: The results showed that NM-Cl presents effective antiseptic action and a prolonged residual effect in the cat venipuncture antisepsis. Studies have been carried out to investigate the NM-Cl in veterinary routine.

Introduction Nanoparticle solutions have been studied to improve antimicrobial effect. The aim of this study was to develop, characterize, and evaluate the in vitro and in vivo antiseptic efficacy of 0.25% aqueous-based chlorhexidine nanoemulsion (NM-Cl 0.25% w/v). Methods The NM-Cl 0.25% w/v (2.5mg/mL) and free chlorhexidine nanoemulsion (FCN; same composition of NM-Cl without the molecule of chlorhexidine) were synthetized by the spontaneous emulsification method. Characterization analyses of physical and chemical properties were performed. The NM-Cl 0.25% w/v was compared with chlorhexidine 0.5% alcohol base (CS-Cl 0.5%) in vitro studies (microdilution study and kill curve study), and in vivo study (antisepsis of rats dorsum). Kruskal-Wallis test was used between groups and inside the same group, at different sample times and the Mann-Whitney test was performed when difference was detected. Results The NM-Cl 0.25% w/v presented adequate physicochemical characteristics for a nanoemulsion, revealing a more basic pH than FCN and difference between zeta potential of NM-Cl 0.25% w/v and FCN. The NM-Cl 0.25% w/v and CS-Cl 0.5% solutions were more effective on Gram-positive than on Gram-negative bacteria (p≤0.05). NM-Cl 0.25% w/v presented upper antiseptic effect in the microdilution study and residual antiseptic effect was maintained for a longer time when compared to CS-Cl 0.5% (kill curve study). The four-fold (minimal inhibitory concentration) of NM-Cl 0.25% were the formulations with most durable effect within those tested, presenting residual effect until T6 for both bacteria. In the in vivo study, both formulations (NM-Cl 0.25% w/v and CS-Cl 0.5%) had a reduction of the microorganisms in the skin of the rats (p

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.

Danofloxacin is a veterinary fluoroquinolone used to treat respiratory and gastrointestinal diseases of birds, pigs and cattle. The literature reviewed shows some analytical methods to quantify this fluoroquinolone, but microbiological and biological safety studies are limited. The analytical methods were validated by the Official Codes. The LC-DAD method was developed and validated using an RP-18 column, mobile phase containing a mixture of 0.3% triethylamine (pH 3.0) and acetonitrile (85:15, v/v). The microbiological assay was performed by agar diffusion method (3 x 3) and Staphylococcus epidermidis as a microorganism test. Forced degradation studies were performed in both methods. The minimum inhibitory concentration (MIC) was performed by test microdilution and toxicity studies were evaluated using in silico study, cell proliferation, cell viability test, micronuclei and comet assay. LC and a microbiological assay proved linear, accurate, precise, and robust to quantify danofloxacin, but only the LC method showed selectivity to quantify the drug in the presence of its degradation products. These results demonstrate that the LC method is suitable for stability studies of danofloxacin, but a microbiological assay cannot be used to quantify the drug due to the biological activity of the photoproducts. Ex-vivo cytotoxicity and theoretical and experimental genotoxicity were also observed.

Introduction Sporothrix schenckii is a thermal dimorphic pathogenic fungus causing a subcutaneous mycosis, sporotrichosis. Nitrocoumarin represents a fluorogenic substrate class where the microbial nitroreductase activity produces several derivatives, already used in several other enzyme assays. The objective of this study was the analysis of 6-nitrocoumarin (6-NC) as a substrate to study the nitroreductase activity in Sporothrix schenckii. Methods Thirty-five samples of S. schenckii were cultivated for seven, 14 and 21 days at 35 °C in a microculture containing 6-nitrocoumarin or 6-aminocoumarin (6-AC) dissolved in dimethyl sulfoxide or dimethyl sulfoxide as a negative control, for posterior examination under an epifluorescence microscope. The organic layer of the seven, 14 and 21-day cultures was analyzed by means of direct illumination with 365 nm UV light and by means of elution on G silica gel plate with hexane:ethyl acetate 1:4 unveiled with UV light. Results All of the strains showed the presence of 6-AC (yellow fluorescence) and 6-hydroxylaminocoumarin (blue fluorescence) in thin layer chromatography, which explains the green fluorescence observed in the fungus structure. Conclusion The nitroreductase activity is widely distributed in the S. schenckii complex and 6-NC is a fluorogenic substrate of easy access and applicability for the nitroreductase activity detection. Introdução Sporothrix schenckii é um fungo dimórfico térmico, agente etiológico de micose subcutânea, a esporotricose. Nitrocumarina representa classe de substratos fluorogênicos em que a atividade nitroredutásica microbiana produz vários derivados, já utilizados em vários outros ensaios enzimáticos. O objetivo deste estudo foi analisar 6-nitrocumarina (6-NC) como substrato para estudo da atividade nitroredutásica em Sporothrix schenckii. Métodos Trinta e cinco isolados de S. schenckii foram cultivados por sete, 14 e 21 dias a 35 °C em um microcultivo contendo 6-nitrocumarina ou 6-aminocumarina (6-AC) solubilizada em dimetilsulfóxido ou dimetilsulfóxido como controle negativo, para posterior análise em microscópio de epifluorescência. A fase orgânica da cultura de sete, 14 e 21 dias foi analisada por meio de iluminação direta com luz UV de 365 nm e por eluição em placas de sílica gel G com hexano:acetato de etila 1:4 e revelada com luz UV. Resultados Todos os isolados mostraram a presença de 6-AC (fluorescência amarela) e 6-hidroxilaminocumarina (fluorescência azul) em cromatografia em camada delgada, que explica a fluorescência verde observada na estrutura dos fungos. Conclusão A atividade nitroredutásica é amplamente distribuída no complexo S. schenckii e 6-NC é um substrato fluorogênico de fácil obtenção e aplicabilidade para detecção da atividade nitroredutásica.

The Sporothrix schenckii complex is the etiologic agent of sporotrichosis, a subacute or chronic mycosis which can affect humans and animals. Killer yeasts have been used in the medical field for development of novel antimycotics and biotyping of pathogenic fungi. The action of 18 killer yeasts on the growth of 88 characterized S. schenckii, Sporothrix globosa, Sporothrix brasiliensis, and Sporothrix mexicana clinical and environmental isolates was evaluated. Killer studies were performed on Petri dishes containing cheese black starch agar. The yeasts Candida catenulata (QU26, QU31, QU127, LV102); Trichosporon faecale (QU100); Trichosporon japonicum (QU139); Kluyveromyces lactis (QU30, QU99, QU73); Kazachstania unispora (QU49), Trichosporon insectorum (QU89), and Kluyveromyces marxianus (QU103) showed activity against all strains of the S. schenckii complex tested. Observation by optical microscopy of S. brasiliensis 61 within the inhibition haloes around the colonies of the killer yeasts QU100, QU139, and LV102 showed that there was no conidiation, but there was hyphal proliferation. The toxins were fungistatic against S. brasiliensis 61. There was no difference in susceptibility to the toxins among the S. schenckii species complex. Further investigations are necessary to clearly establish the mechanism of action of the toxins.

The ability to understand the features of the white blood cell is an important skill for medical undergraduates. The objective was to develop a game that would improve medical students' knowledge about the value and interpretation of the white blood cell. The game consists of 63 cards, including different clinical cases involving conditions that modify white blood cell count, related laboratory findings, and the respective diagnosis. The objective of the game was to match the three groups of cards, explaining their association. The evaluation tools included pretests and posttests, in addition to a structured questionnaire to identify the overall perception of the game. The game was applied to 90 undergraduate pre-clinical medical students of the Universidade Federal do Rio Grande do Sul, Brazil. The results of this study show that pretest and posttest mean scores were 8.6 ( ± 1.62) and 9.27 ( ± 1.30), with a statistically significant difference. Thirty-seven students (39.4%) did not know the answer to at ...

The yeasts of the genus Candida infect skin, nails, and mucous membranes of the gastrointestinal and the genitourinary tract. The aim of this study was to determine the prevalence of dermatomycoses caused by Candida spp., and their etiological aspects in the metropolitan area of Porto Alegre, Brazil. A retrospective study with data obtained from tertiary hospital patients, from 1996 to 2011, was performed. The analyzed parameters were date, age, gender, ethnicity, anatomical region of lesions, and the direct examination results. For all the statistical analyses, a = 0.05 was considered. Among positive results in the direct mycological examination, 12.5% of the total of 4,815 cases were positive for Candida spp. The angular coefficient (B) was -0.7%/ year, showing a decrease over the years. The genus Candida was more prevalent in women (15.9% of women versus 5.84% of men), and in addition, women were older than men (54 versus 47 years old, respectively). There was no difference between ethnic groups. The nails were more affected than the skin, with 80.37% of the infections in the nails (72.9% in fingernails and 7.47% in toenails). Our study corroborates the literature regarding the preference for gender, age, and place of injury. Moreover, we found a decrease in infection over the studied period.

The aim of this study was to develop and characterize antigens for the diagnosis of aspergillosis. Nine strains of Aspergillus species Aspergillus fumigatus , Aspergillus flavus , and Aspergillus niger were grown in Sabouraud and Smith broth to produce exoantigens. The antigens were tested by immunodiffusion against sera from patients with aspergillosis and other systemic mycoses. The protein fraction of the antigens was detected by SDS–PAGE; Western blot and representative bands were assessed by mass spectrometry coupled to a nano Acquity UltraPerformance LC and analyzed by the Mascot search engine. Concurrently, all sera were tested with Platelia Aspergillus EIA. The most reactive antigens to sera from patients infected by A. fumigatus were produced by A. fumigatus MG2 Sabouraud and pooled A. fumigatus Sabouraud samples, both with a sensitivity of 93% and specificity of 100% and 97%, respectively. Aspergillus niger and A. flavus antigens were reactive against A. niger and A. flavus sera, each one with a sensitivity and specificity of 100%. Two proteins, probably responsible for antigenic activity, β-glucosidase in A. fumigatus and α-amylase in A. niger were attained. The commercial kit had a specificity of 22%, sensitivity of 100%, positive predictive value of 48%, and negative predictive value of 100%. The antigens produced showed high sensitivity and specificity and can be exploited for diagnostics of aspergilloma.

Several studies have reported that guanylhydrazones display a variety of desirable biological properties, such as antihypertensive, antibacterial, and antimalarial behaviour. They furthermore promote anti-pneumocystosis and anti-trypanosomiasis, exhibit antitumor activity, and show significant cytotoxicity against cancer cell lines. In this work, we have evaluated the cytotoxicity, mutagenicity, and genotoxicity of two guanylhydrazones derivatives, (E)-2-[(2,3-dimethoxyphenyl) methylene] hydrazine carboxymidamide hydrochloride (2,3-DMeB) and (E)-2-[(3,4-dimethoxyphenyl) methylene] hydrazine carboxymidamide hydrochloride (3,4-DMeB), in different biological models. Both 2,3-DMeB and 3,4-DMeB induce weak cytotoxic and mutagenic effects in bacteria and yeast. The genotoxicity of these compounds was determined in a fibroblast cell line (V79) using alkaline comet assay, as well as a modified comet assay with bacterial enzymes formamidopyrimidine DNA-glycosylase (FPG) and endonuclease III (EndoIII). Both guanylhydrazone derivatives induced DNA damage. Treatment of V79 cells with EndoIII and FPG proteins demonstrated a significant effect of 2,3-DMeB and 3,4-DMeB with respect to oxidized bases. In addition, the derivatives induced a significant increase in the frequency of micronucleated cells at high doses. The antifungal and anti-trypanosomal properties of these guanylhydrazone derivatives were also evaluated, and the obtained results suggest that 2,3-DMeB is more effective than 3,4-DMeB. The biological activity of 2,3-DMeB and 3,4-DMeB may thus be related, at least in part, to their oxidative potential, as well as to their ability to interact with DNA. Considering the previously reported in vitro antitumor activity of guanylhydrazone derivatives in combination with the lack of acute toxicity and the fact that DNA damage is only observed at high doses should render both compounds good candidates for in vivo studies on antitumor activity.

Summary Plants of the genus Pterocaulon (Asteraceae) are popularly used in the treatment of skin diseases caused by fungi and bacteria. The aim of this work was to investigate the in vitro activity of the crude methanolic extracts obtained from the aerial parts of Pterocaulon polystachyum, P. balansae, P. lorentzii, P. lanatum, and P. cordobense against 24 Sporothrix schenckii clinical isolates and determine the minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC). MIC were performed by the broth microdilution method according guidelines recommended by Clinical and Laboratory Standards Institute for filamentous fungi and MFC were determined for transference of aliquots of the well that showed 100% of growth inhibition into tubes with culture medium. The extract from P. polystachyum was the most active sample, presenting MIC range of 156 and 312 μg/mL. The popular use of these plants corroborates the importance of ethnopharmacological surveys and opens the possibility for finding new clinically effective antifungal agents.

FUNDAMENTOS: As dermatofitoses apresentam alta prevalência na população em geral e, principalmente, em pacientes com insuficiência renal crônica, necessitando tratamento com antifúngicos tópicos e/ou sistêmicos, cuja eficácia precisa ser avaliada. Estudos in vitro para avaliar a ação de antifúngicos são raros, especialmente, em fungos filamentosos. OBJETIVO: Avaliar o perfil de suscetibilidade de diferentes espécies de dermatófitos, isolados de pacientes com insuficiência renal crônica, em relação a nove antifúngicos disponíveis comercialmente para o tratamento de dermatofitoses. MÉTODO: Analisaram-se 26 isolados de dermatófitos de pacientes com insuficiência renal crônica em relação a nove antifúngicos (cetoconazol, ciclopirox olamina, fluconazol, griseofulvina, itraconazol, miconazol, piroctona olamina, terbinafina e tioconazol) pelo método de microdiluição em caldo proposto pelo Clinical and Laboratory Standards Institute (CLSI), com modificações para dermatófitos. RESULTADOS: Entre os antifúngicos testados, a terbinafina e o tioconazol obtiveram os melhores resultados de sensibilidade e o fluconazol apresentou baixa atividade, especialmente para as amostras da espécie M. gypseum. O ciclopirox olamina, apesar de menos eficaz que a terbinafina, também mostrou resultados satisfatórios. CONCLUSÕES: De modo geral, o perfil de sensibilidade dos antimicóticos testados seguiu o padrão de resultados mostrados por estudos anteriores, ratificando a necessidade de conhecimento da espécie causadora de dermatofitose, devido à variação do perfil de suscetibilidade entre as espécies. Além disso, nossos resultados demonstram a importância da realização de ensaios de sensibilidade in vitro, pois alguns isolados da mesma espécie apresentaram diferente perfil de sensibilidade. BACKGROUND: The prevalence of dermatophytosis in the general population is high, particularly in patients with chronic renal failure. Treatment requires the use of topical and/or systemic antifungal drugs. The efficacy of antifungal agents for the treatment of dermatophytosis has yet to be evaluated. Studies evaluating the in vitro activity of antifungal agents are rare, particularly in filamentous fungi. OBJECTIVE: To evaluate the susceptibility profile of different species of dermatophytes isolated from patients with chronic renal failure to nine antifungal drugs available on the market for the treatment of dermatophytosis. METHODS: Twenty-six isolates of dermatophytes obtained from patients with chronic renal failure were analyzed with respect to their susceptibility to nine antifungal agents (ketoconazole, ciclopirox olamine, fluconazole, griseofulvin, itraconazole, miconazole, piroctone olamine, terbinafine and tioconazole), using the broth microdilution method proposed by the Clinical and Laboratory Standards Institute (CLSI) and adapted for dermatophytes. RESULTS: Of the antifungal agents tested, the best results in terms of sensitivity were found with terbinafine and tioconazole, while the antifungal activity of fluconazole was found to be weak, particularly against strains of M. gypseum. Ciclopirox olamine, although less effective than terbinafine, also yielded satisfactory results. CONCLUSIONS: In general, the sensitivity profile of the antifungal agents tested in this study was similar to results obtained in previous studies, confirming the need to determine which species is causing the dermatophytosis given that antifungal susceptibility varies from one species to another. Furthermore, the present findings show the importance of conducting in vitro sensitivity tests, since the sensitivity profile may differ among isolates of the same species.

Purpose: The aim of this study was to assess the efficacy of peracetic acid (PAA) for the disinfection of dental acrylic resins experimentally contaminated with Candida albicans, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. Methods: Fifteen materials were used for each type of resin (thermosetting, self-curing and microwave-curing). Each material was placed in a test tube containing culture medium with a suspension of each microorganism and then incubated. The materials were rinsed and transferred to other tubes containing 50 mL of water for 5 min, 0.2% peracetic acid for 5 min or glutaraldehyde for 30 min. The materials were placed in the culture agar and incubated. Microbial growth was determined by colony counting after plating. Results: Candida albicans growth was inhibited by peracetic acid and glutaraldehyde treatments. The number of colonies on resins treated with saline was greater than 105 CFU/mL. In resins infected with E. coli, S. aureus and P. aeruginosa the colony growth was not inhibited by saline and peracetic acid, but it was totally inhibited by glutaraldehyde. Conclusion: Surface disinfection using peracetic acid effectively inhibited C. albicans growth on all acrylic resins. Objetivo: O objetivo deste estudo foi avaliar a eficácia do ácido peracético (PAA) na desinfecção de resinas acrílicas dentais experimentalmente contaminadas com Candida albicans, Escherichia coli, Staphylococcus aureus e Pseudomonas aeruginosa. Metodologia: Quinze corpos de prova (CP) foram utilizados para cada tipo de resina (termopolimerizáveis, autopolimerizáveis e ativados por energia de micro-ondas). Cada CP foi colocado em um tubo teste com meio de cultura contendo uma suspensão de cada microrganismo e incubado. Posteriormente, os CP foram lavados e transferidos para outros tubos contendo 50 mL de água por 5 minutos, em 0,2% de ácido peracético por 5 min ou em glutaraldeído por 30 minutos, plaqueados em ágar de cultura e incubados. O crescimento microbiano foi determinado por contagem de colônias após o plaqueamento. Resultado: O crescimento de Candida albicans foi inibido nos tratamentos com ácido peracético e glutaraldeído. O número de colônias nas resinas tratadas com solução salina foi superior a 105 UFC/mL. Nas resinas infectadas com E. coli, S. aureus e P. aeruginosa, o crescimento das colônias não foi inibido nas resinas tratadas com salina e ácido peracético, mas foi totalmente inibida pelo glutaraldeído. Conclusão: A desinfecção com ácido peracético inibiu efetivamente o crescimento de C. albicans em todas as resinas acrílicas.

O objetivo deste trabalho foi identificar a atividade lipolítica de cepas de Sporothrix schenckii utilizando Rodamina B como indicador da hidrólise de triglicerídios (trioleína do óleo de oliva) e comparar estes resultados com a utilização de Tween 80 como substrato. Ácidos graxos livres liberados da atividade lipolítica foram detectados através da emissão de fluorescência laranja em ágar, quando exposto à luz UVA, ou através de halos de precipitação em ágar Tween 80. Não houve diferenças na atividade lipolítica entre as cepas bem como meios de cultivo utilizados. A maior atividade lipolítica (fluorescência laranja) foi observada na biomassa de 10 cepas, sem halos fluorescents ao redor das colônias, enquanto apenas seis isolados apresentaram grandes halos de precipitação. Esses ensaios em placa são úteis para a detecção de S. schenckii produtores de lipase na fase leveduriforme, mas ainda se desconhece se são diferentes enzimas atuando sobre os substratos ou se são variações da mesma enzima com diferentes especificidades.

SUMMARY Pityriasis versicolor is the most common of the diseases caused by Malasseziayeasts. The aim of this study is to determine the prevalence of pityriasis versicolor and its etiological aspects in the metropolitan area of Porto Alegre, Brazil. A retrospective crosssectional study with data from patients of a reference hospital from 1996 to 2011 was performed. Collected data included: date, age, gender, ethnicity, anatomical region of lesion and the direct mycological examination results. Among the positive results in the direct mycological examination, 5.8% (2,239) were positive for pityriasis versicolor. The angular coefficient (B) was -0.3%/year, showing a decrease over the years. The disease was more prevalent in men (7.1% of men versus 5.1% of women that underwent the direct mycological examination); younger age (median 31 years old); "pardo" and black people (3.7% more than expected in the sample); trunk (73.44% of the affected anatomic sites). Lesions in rare sites (groin, genitals, legs, feet and hands) were also observed in this study. In conclusion, due to the decrease in the prevalence of pityriasis versicolor, long-term epidemiological studies in the metropolitan area of Porto Alegre, Brazil, are needed to continue the monitoring of this disease. RESUMO Pitiríase versicolor é a mais comum das doenças causadas pelas leveduras do gênero Malassezia. O objetivo do trabalho foi determinar a prevalência de pitiríase versicolor e seus aspectos etiológicos na região metropolitana de Porto Alegre, Brasil. Foi realizado um estudo retrospectivo transversal com dados de pacientes de hospital de referência entre 1996 a 2011. Os dados coletados foram: data, idade, gênero, etnia, local anatômico da lesão e resultados do exame micológico direto. Dentre os resultados positivos do exame micológico direto, 5,8% (2.239) foram positivos para pitiríase versicolor. O coeficiente angular (B) foi -0,3%/ ano, mostrando uma diminuição ao longo dos anos. A doença foi mais prevalente em homens (7,1% dos homens versus 5,1% das mulheres que se submeteram ao exame micológico direto); jovens (mediana de 31 anos); pardos e pretos (3,7% acima do esperado para a amostra); tronco (73,4% dos locais anatômicos afetados). Lesões em locais raros (virilha, genitálias, pernas, pés e mãos) também foram observadas no estudo. Em conclusão, devido à diminuição da prevalência de pitiríase versicolor, estudos epidemiológicos de longo prazo são necessários para continuar o monitoramento da doença na região metropolitana de Porto Alegre, Brasil.

Introduction: Dermatophytoses are considered a public health problem. The objectives of this study were to determine the evolution of their prevalence in the metropolitan area of Porto Alegre, Brazil, and to analyze the dermatophyte species distribution according to body site and demographic characteristics of the patients. Methodology: This work was a retrospective analysis of data from patients attending a tertiary care hospital during 1996–2011. Results: There were 9,048 cases with cultures positive for dermatophytes. Trichophyton rubrum occurred in 59.6% of the cases, followed by Trichophyton interdigitale (34%), Microsporum canis (2.6%), Epidermophyton floccosum (1.5%), Microsporum gypseum (1.3%), and Trichophyton tonsurans (0.9%). The angular coefficients for T. interdigitale , E. floccosum , T. rubrum , and M. canis were +1.119, +0.211, -0.826 and -0.324% per year, respectively. Males presented higher prevalence of infection (79.3% versus 53.9%). Tinea unguium occurred in 48.5% of the cases, followed by tinea pedis (33.1%). T. rubrum was the predominant species in all regions of the body except the scalp, where M. canis was responsible for 75% of the cases. Conclusion: Monitoring of the evolution of dermatophytosis tracks changes in prevalence over the years and may assist practical measures for the public health control of this disease.

Sporotrichosis is a subacute or chronic mycosis caused worldwide by the dimorphic species complex, Sporothrix schenckii. We studied 85 isolates recovered in Brazil to verify their identification and evaluate their in vitro antifungal susceptibility patterns. Based on phenotypic tests (microscopic features, ability to grow at 30 ◦ Ca nd 37 ◦ C, colony diameters, as well as assimilation of sucrose and raffinose) and molecular assays (amplification of a fragment of the calmodulin gene), the strains were identified as S. schenckii, S. brasiliensis and S. globosa, with a predominance of S. schenckii isolates. There was 37.7% disagreement between the phenotypic and genotypic identification methodologies. In general, terbinafine was the most active drug, followed by ketoconazole and itraconazole, and the less active fluconazole and voriconazole. Five isolates (one S. globosa and four S. schenckii) were found to be itraconazole-resistant strains but, in general, there were no differences in the in vitro antifungal susceptibility profiles among the Sporothrix species.

Onychomycosis is one of the most frequent infections affecting the fingernails or the toenails and it is caused mainly by dermatophytes. The aim of the study was to assess the frequency of onychomycoses in hemodialysis patients and to relate sex, age, duration of hemodialysis and causes of renal failure to the development of nail disorders. The study included 100 patients with chronic renal failure undergoing hemodialysis. The patients underwent detailed clinical examination of the toenails and those with any kind of clinical finding had nail scraping for mycological testing. In the study population, the frequency of onychomycosis was 39%. The most commonly isolated fungi were dermatophytes (69.23%), Candida spp. (15.38%) and nondermatophyte molds (15.38%). T. interdigitale was the most prevalent fungus followed by Candida ssp. and T. rubrum. The risk of onychomycosis increases by 1.9% for each additional year in age and diabetic patients are 88% more likely to develop onychomycosis than nondiabetic ones. The duration of hemodialysis treatment and sex were not associated with the development of onychomycosis. In conclusion, in hemodialysis patients, the frequency of onychomycosis was higher in those at advanced age and with diabetes.

The Sporothrix schenckii complex is the etiologic agent of sporotrichosis, a subacute or chronic mycosis which can affect humans and animals. Killer yeasts have been used in the medical field for development of novel antimycotics and biotyping of pathogenic fungi. The action of 18 killer yeasts on the growth of 88 characterized S. schenckii, Sporothrix globosa, Sporothrix brasiliensis, and Sporothrix mexicana clinical and environmental isolates was evaluated. Killer studies were performed on Petri dishes containing cheese black starch agar. The yeasts Candida catenulata (QU26, QU31, QU127, LV102); Trichosporon faecale (QU100); Trichosporon japonicum (QU139); Kluyveromyces lactis (QU30, QU99, QU73); Kazachstania unispora (QU49), Trichosporon insectorum (QU89), and Kluyveromyces marxianus (QU103) showed activity against all strains of the S. schenckii complex tested. Observation by optical microscopy of S. brasiliensis 61 within the inhibition haloes around the colonies of the killer yeasts QU100, QU139, and LV102 showed that there was no conidiation, but there was hyphal proliferation. The toxins were fungistatic against S. brasiliensis 61. There was no difference in susceptibility to the toxins among the S. schenckii species complex. Further investigations are necessary to clearly establish the mechanism of action of the toxins.

BACKGROUND: The standard methodology for determining the antifungal sensitivity against the Sporothrix schenckii complex recommends the use of the 1640 Roswell Park Memorial Institute culture medium (RPMI) buffered with morpholinepropanolsulfonic acid (MOPS). However, while this is a high-cost medium which requires a laborious implementation and sterilization by filtration, the Sabouraud dextrose broth is a low-cost medium, widely used in mycology, sterilized by autoclave. OBJECTIVE: To evaluate the performance of the Sabouraud dextrose broth culture medium as a substitute for the RPMI 1640-MOPS in determining the antifungal sensitivity of S. schenckii. METHODS: Forty-eight clinical isolates were evaluated against five antifungal agents: itraconazole, ketoconazole, fluconazole, amphotericin B and terbinafine, using the method of broth microdilution advocated by the M38-A2 protocol of the Clinical and Laboratory Standards Institute. RESULTS: There were no significant differences between the Minimum Inhibitory Concentrations obtained in the two culture media for all the antifungals, with the exception of the amphotericin B. Regarding this drug, the Minimum Inhibitory Concentration range obtained were wider for the Sabouraud dextrose broth than for the Roswell Park Memorial Institute morpholinepropanelsulfonic acid. CONCLUSIONS: The Sabouraud dextrose broth showed potential to be used in the in vitro evaluation of the S. schenckii complex antifungal activity. FUNDAMENTOS: A metodologia padronizada para a determinação da sensibilidade aos antifúngicos frente ao complexo Sporothrix schenckii preconiza a utilização do meio de cultura Roswell Park Memorial Institute (RPMI) 1640 tamponado com ácido morfolinopropanosulfônico (MOPS). No entanto, este meio possui custo elevado, execução trabalhosa e esterilização por filtração. Já o caldo Sabouraud-dextrose é amplamente utilizado em micologia, de baixo custo e pode ser esterilizado por autoclavagem. OBJETIVO: Avaliar o desempenho do meio de cultura caldo Sabouraud-dextrose em substituição ao RPMI 1640-MOPS na determinação da sensibilidade de S. schenckii a antifúngicos. MÉTODO: Foram avaliados 48 isolados clínicos frente a cinco antifúngicos: itraconazol, cetoconazol, fluconazol, anfotericina B e terbinafina, utilizando a metodologia da microdiluição em caldo preconizada pelo protocolo M38-A2 do Clinical and Laboratory Standards Institute. RESULTADOS: Não houve diferenças significativas nas Concentrações Inibitórias Mínimas obtidas nos dois meios de cultura para todos os antifúngicos, com exceção da anfotericina B. Para este fármaco, foram obtidas faixas mais amplas de Concentrações Inibitórias Mínimas para caldo Sabouraud-dextrose do que para Roswell Park Memorial Institute-morfolinopropanosulfônico. CONCLUSÕES: O caldo Sabouraud-dextrose mostrou potencial para ser utilizado na avaliação in vitro da atividade antifúngica do complexo S. schenckii.

A esporotricose e uma infeccao subaguda ou cronica, causada por fungos pertencentes ao Complexo Sporothrix. Relato do caso: esporotricose de localizacao nasal foi tratada com iodeto de potassio e como nao se obteve sucesso, reiniciou-se o tratamento com associacao de iodeto de potassio e itraconazol. Porem, ocorreu nova recidiva. As culturas dos exames micologicos foram submetidas a ensaios de atividade antifungica in vitro para auxiliar no tratamento. A terbinafina foi o antifungico que apresentou melhores resultados, por isso, o tratamento foi reiniciado com este antifungico e, apos dois anos do termino do mesmo, nao recidivou. Adicionalmente, ambas as culturas foram comparadas por RAPD, obtendo padroes de fragmentos distintos, indicando que os isolados sao diferentes ou demonstrando um processo microevolutivo do microrganismo. Sporotrichosis is a chronic subacute infection caused by fungi belonging to the Sporothrix Complex. In the present clinical case, nasal sporotrichosis was treated with potassium iodide. This was unsuccessful, and the treatment was restarted with a combination of potassium iodide and itraconazole. This however resulted in a further recurrence of the infection. The mycological cultures were tested in vitro for antifungal activity to assist in treatment. Terbinafine, an antifungal drug, produced the best results and was therefore used for the rest of the treatment course, with no recurrence after two years of its completion. In addition, both cultures were compared using RAPD and different fragment patterns were observed. This indicated that the isolates were either different or indicated a microevolutionary process of this microorganism.

Sporotrichosis is a chronic subacute infection caused by fungi belonging to the Sporothrix Complex. In the present clinical case, nasal sporotrichosis was treated with potassium iodide. This was unsuccessful, and the treatment was restarted with a combination of potassium iodide and itraconazole. This however resulted in a further recurrence of the infection. The mycological cultures were tested in vitro for antifungal activity to assist in treatment. Terbinafine, an antifungal drug, produced the best results and was therefore used for the rest of the treatment course, with no recurrence after two years of its completion. In addition, both cultures were compared using RAPD and different fragment patterns were observed. This indicated that the isolates were either different or indicated a microevolutionary process of this microorganism.

The prevalence of dermatophytosis in the general population is high, particularly in patients with chronic renal failure. Treatment requires the use of topical and/or systemic antifungal drugs. The efficacy of antifungal agents for the treatment of dermatophytosis has yet to be evaluated. Studies evaluating the in vitro activity of antifungal agents are rare, particularly in filamentous fungi.To evaluate the susceptibility profile of different species of dermatophytes isolated from patients with chronic renal failure to nine antifungal drugs available on the market for the treatment of dermatophytosis.Twenty-six isolates of dermatophytes obtained from patients with chronic renal failure were analyzed with respect to their susceptibility to nine antifungal agents (ketoconazole, ciclopirox olamine, fluconazole, griseofulvin, itraconazole, miconazole, piroctone olamine, terbinafine and tioconazole), using the broth microdilution method proposed by the Clinical and Laboratory Standards Institute (CLSI) and adapted for dermatophytes.Of the antifungal agents tested, the best results in terms of sensitivity were found with terbinafine and tioconazole, while the antifungal activity of fluconazole was found to be weak, particularly against strains of M. gypseum. Ciclopirox olamine, although less effective than terbinafine, also yielded satisfactory results.In general, the sensitivity profile of the antifungal agents tested in this study was similar to results obtained in previous studies, confirming the need to determine which species is causing the dermatophytosis given that antifungal susceptibility varies from one species to another. Furthermore, the present findings show the importance of conducting in vitro sensitivity tests, since the sensitivity profile may differ among isolates of the same species.

Dihydroxyacetone (DHA), a three-carbon sugar, is the browning ingredient in commercial sunless tanning formulations. DHA preparations have been used for more than 50 years and are currently highly popular for producing temporary pigmentation resembling an ultraviolet-induced tan. In this work, the in vitro antifungal activity of dihydroxyacetone was tested against causative agents of dermatomycosis, more specifically against dermatophytes and Candida spp. The antifungal activity was determined by the broth microdilution method according to the Clinical and Laboratory Standards Institute guidelines for yeasts and filamentous fungi. The data obtained show that the fungicidal activity varied from 1.6 to 50 mg ml(-1). DHA seems to be a promising substance for the treatment of dermatomycosis because it has antifungal properties at the same concentration used in artificial suntan lotions. Therefore, it is a potential low-toxicity antifungal agent that may be used topically because of its penetration into the corneal layers of the skin.

We report a case of a researcher from a laboratory of Mycology in Rio Grande do Sul, Brazil that presented a clinical evidence of sporotrichosis. The researcher had an accident while manipulating the microculture slides of chromoblastomycosis agents and presented a clinical evidence of sporotrichosis. As the laboratory has some cultures of Sporothrix schenckii, it was suggested that it might be a laboratory contamination. In order to test this hypothesis, the genotypic characterization of the samples was performed by means of the random amplified polymorphic DNA (RAPD) analysis method. In addition, we evaluated the in vitro antifungal activity of four antifungal agents against the isolated fungus. The sample obtained from the researcher was not genetically similar to any of the samples kept in the laboratory and showed the minimum inhibitory concentrations of 0.5 μg/mL for itraconazole and ketoconazole, >64 μg/mL for fluconazole and 0.125 μg/mL for terbinafine. It is suggested that the contamination had an environmental origin.

Plants of the genus Pterocaulon (Asteraceae) are popularly used in the treatment of skin diseases caused by fungi and bacteria. The aim of this work was to investigate the in vitro activity of the crude methanolic extract obtained from the aerial parts of Pterocaulon alopecuroides (Lam.) against some agents of chromoblastomycosis, a chronic fungal infection of the skin and of the subcutaneous tissue caused by traumatic inoculation of the aetiological agent. The extract was active against all the strains tested showing a minimum inhibitory concentration between 625 and 2500 microg ml(-1). The assessment of fungistatic/fungicidal activity demonstrated that the extract was fungistatic against Fonsecaea spp. and fungicidal against all the other fungi. Our results indicate that the identification of bioactive components present in the crude methanolic extract of P. alopecuroides against chromoblastomycosis agents can be an important strategy to manage this mycosis in the future.

The development of azole antifungals has allowed for the treatment of several fungal infections. However, the use of these compounds is restricted because of their hepatotoxicity or because they need to be administered together with other drugs in order to prevent resistance to monotherapy. Benzoxazole derivatives are among the most thriving molecular prototypes for the development of antifungal agents. 2-(2'-hydroxyphenyl) benzoxazoles are versatile molecules that emit fluorescence and have antibacterial, antiviral and antifungal properties. 2-(2'-hydroxy-5'-aminophenyl) benzoxazole (HAMBO) was tested against Candida yeast. The inhibition provided by HAMBO was lower than that of fluconazole, showing low antifungal activity against Candida spp., but equivalent to that of benzoxazoles tested in similar studies. HAMBO showed fungistatic activity against all analysed strains. This class of novel benzoxazole compounds may be used as template to produce better antifungal drugs.

Objective: The objective of this study was to evaluate the behavior of intra-arch latex elastic of different brands and colors when subjected to disinfection procedures. Methods: A total of 320 units of American Orthodontics elastic; Morelli and Uniden were selected and divided into four groups according to the performed disinfection process: autoclave - 15 minutes; hypochlorite - 20 minutes; glutaraldehyde - 30 minutes and control. The disinfecting agents and the disinfection time were defined by a prior microbiological test. Before and after disinfection, by means of a universal trial machine, the maximum generated strength – until the rupture occurred – was evaluated. Results: The autoclave disinfection reduced significantly the strength generated by elastic, in 75% of the brands. The disinfection in hypochlorite increased significantly the strength generated by Morelli elastic; probably the alteration to its elastic property increased its rigidity. Neither the Yellow Uniden nor the American elastic suffered any significant reduction in strength as the result of hypochlorite disinfection. The glutaraldehyde was the disinfectant solution with less significant effect on the strength of the bands, affecting only the Green Uniden. Conclusion: The results suggest that the 2% glutaraldehyde is the disinfectant less aggressive to the elastic performance.