Essential oil (EO) of the leaves of Eugenia uniflora L. (Brazilian cherry tree) was evaluated for its antioxidant, antibacterial and antifungal properties. The acute toxicity of the EO administered by oral route was also evaluated in mice. The EO exhibited antioxidant activity in the DPPH, ABTS and FRAP assays and reduced lipid peroxidation in the kidney of mice. The EO also showed antimicrobial activity against two important pathogenic bacteria, Staphylococcus aureus and Listeria monocytogenes, and against two fungi of the Candida species, C. lipolytica and C. guilliermondii. Acute administration of the EO by the oral route did not cause lethality or toxicological effects in mice. These findings suggest that the EO of the leaves of E. uniflora may have the potential for use in the pharmaceutical industry.

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As drogas antifúngicas são classificadas em agentes químicos clássicos e atuais e em antibióticos. Os agentes químicos clássicos são aqueles medicamentos que apresentam de maneira geral espectro de ação reduzido contra fungos, atuando como fungistático de modo indireto ao modificar as condições locais, como por exemplo o iodo, os ácidos graxos e derivados, ácido salicílico, tolnaftato e tolciclato. Os agentes químicos atuais são representados pelos imidazóis e triazóis, flucitosina e alilaminas e os antibióticos representados pelos poliênicos (anfotericina B, nistatina e natamicina) e a griseofulvina. A descrição de cada antifúngico considerado será apresentada no trabalho.

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Malassezia pachydermatis is recognized as a normal inhabitant and an opportunistic pathogen of the external ear canal and skin of dogs and cats. In especial clinical conditions, and mainly in the cases of therapeutic failure related to external otitis and dermatitis complicated by this yeast, it is recommended test susceptibility to antifungal drugs. The purpose of this work was to evaluate the susceptibility of 44 isolates of M. pachydermatis from the external ear canal and skin of dogs and cats using two different in vitro antifungal susceptibility methods: the Etest® and the broth microdilution method. Thirty-five samples were tested using the Etest®, twenty-four samples were tested using the broth microdilution method and fifteen samples were tested using both tests. The antifungal agents used were ketoconazole (KTZ), fluconazole (FLZ) and itraconazole (ITZ). In the broth microdilution method the yeast was less susceptible to ITZ while KTZ had the strongest activity. On the other hand, the Etest® showed that M. pachydermatis was more susceptible to ITZ while the less active drug was FLZ. The simultaneous evaluation using both methods identified FLZ as the antifungal drug with the highest activity (64.3%), followed by KTZ (57.1%) and ITZ (28.6%). These results showed that there is an urgent need to standardize of the values considered as parameters for growth inhibition of this yeast so a simple and efficient method can be used routinely in the laboratory practice.

Thiabendazole, classified as antiparasitic and also used as an antifungal drug, can be found as otological solution indicated for treatment of parasitic and fungal external otitis in small animals. Malassezia pachydermatis is a yeast recognized as a normal inhabitant on the skin and mucous membranes of dogs and cats. However, it is considered an opportunistic agent that causes external otitis and dermatitis in these animals. The aim of this study was to evaluate the in vitro effect of thiabendazole against 51 isolates of M. pachydermatis using the CLSI Broth Microdilution method that has been adapted for this yeast species (NCCLS, 2002). Based on this test, the Minimum Inhibitory Concentrations (MIC) of thiabendazol was calculated. Subsequently, the susceptibility of each isolate against this antifungal was determined. It was observed that the MIC of thiabendazole against M. pachydermatis ranged from 0.03 to > 4 µg/mL. A total of 13.7% of the isolates were found to be resistant, 47.1% were intermediate and 39.2% were sensitive to the drug. The rate of resistance of the yeasts against thiabendazole was similar to the results previously obtained with other antifungals, while the adapted broth microdilution technique used in this study proved to be efficient.

RESUMOIntrodução: O Cryptococcus neoformans é uma levedura capsulada, agente etiológico da criptococose em humanos e animais, encontrado em fontes ambientais, incluindo excretas de pombos, é uma importante causa de mortalidade em indivíduos imunodeprimidos em todo o mundo. Métodos: com o objetivo de verificar a ocorrência do Cryptococcus neoformans, em excretas de pombos, na cidade de Pelotas, pesquisou-se 70 ambientes, incluindo prédios, praças e locais ao ar livre, da cidade de Pelotas, RS. Após a coleta, os excrementos foram adicionados de salina com cloranfenicol, homogeneizados, semeados em ágar Sabouraud com cloranfenicol e ágar Níger e incubados a 32ºc. Para identificação, realizou-se exame direto, prova da fenoloxidase, urease, assimilação de carboidratos e cultura em meio cGB. Resultados: Dos locais estudados (nº =70), em 26 (37,1%) havia excretas de pombos. Estes lugares foram representados por prédios históricos (nº =8), torre de igreja (nº =1), engenhos e armazéns de arroz (nº =7), praça (nº =1) e locais ao ar livre (nº =9), o isolamento de Cryptococcus neoformans ocorreu em 26,9% (nº =7/26), destes locais. Conclusões: O estudo chama a atenção, para o isolamento do fungo em áreas urbanas, que apresentavam grande acúmulo de excretas, indicando um risco para a saúde pública, especialmente para indivíduos imunocomprometidos. Palavras-chaves: Cryptococcus neoformans. Excretas. Pombos. Ambiente. Urbano. ABSTRACT Introduction:Cryptococcus neoformans is an encapsulated yeast and is the etiological agent for human and animal cryptococcosis. It is found in sources within the environment, including pigeon excrement, and is an important cause of mortality among immunocompromised individuals worldwide. Methods: Seventy different environments in the city of Pelotas, Rio Grande do Sul, were surveyed for the purpose of investigating Cryptococcus neoformans occurrences in pigeon excreta. The environments included buildings, public squares and outdoor locations in the city. After collection, chloramphenicol saline solution was added to the excreta, which were then homogenized and seeded onto Sabouraud agar with chloramphenicol and onto Niger agar, and incubated at 32°c. Identification was performed by direct examination and by means of the phenoloxidase and urease tests, carbohydrate assimilation and culturing in cGB medium. Results: Out of the sites investigated (n = 70), 26 (37.1%) of them contained pigeon excreta. These included historical buildings (n = 8), a church tower (n = 1), rice mills and warehouses (n = 7), a public square (n = 1) and outdoor locations (n = 9). Cryptococcus neoformans was isolated from 26.9% (n = 7/26) of these locations. Conclusions: This study draws attention to isolation of this fungus in urban areas that present large accumulations of pigeon excrement. This represents a risk to public health, especially for immunocompromised individuals.

The purpose of this work was to evaluate the frequency of Malassezia pachydermatis infection and other infectious agents in dogs with external otitis and with healthy auditory tubes. Clinical manifestations of external otitis were evaluated. Samples from the auditory tube of 102 dogs with otitis and from 32 healthy dogs were submitted to direct microscopic examination and cultured in blood agar and Sabouraud dextrose agar with chloramphenicol and cycloheximide. Direct examination showed more than ten cells of M. pachydermatis in 52.0% of the samples from dogs with otitis, but in only 21.8% of the healthy auditory tube samples. M. pachydermatis was isolated in 37.5% of the samples from dogs with healthy auditory tube and 76.5% (p<0.01) of the samples from dogs with otitis. There was an association between M. pachydermatis and Staphylococcus aureus (p<0.01), but not with Pseudomonas aeruginosa (p>0.05). Infection by M. pachydermatis was prevalent in the following breeds: Cocker Spainel, German Shepherd and Brazilian Fila. No differences were found in frequency of the infection in relation to age, sex and ear anatomy of the dogs. Otomycosis were predominantly ceruminous and erythematous. M. pachydermatis was the most frequent agent in external otitis.