Infecções por leveduras são freqüentes em imunocomprometidos, contudo espécies emergentes têm alterado o perfil epidemiológico. A habilidade de secretar proteases tem sido associada à patogenicidade do gênero Candida. Esta pesquisa teve como objetivos diagnosticar leveduroses em pacientes imunocomprometidos e avaliar a virulência dos agentes etiológicos baseado em teste de secreção de protease utilizando soro de albumina bovina como substrato. Do total de 104 pacientes estudados, 19 apresentaram episódios de leveduroses. O trato respiratório (63,2%), seguido pelo trato urinário (10,5%) foram os locais mais comuns de infecção. Candida albicans, Candida parapsilosis, Candida tropicalis e espécies emergentes como Candida krusei e Candida guilliermondii foram isoladas. Cinco isolados de Candida parapsilosis e um de Candida albicans e Candida guilliermondii exibiram alta atividade enzimática. Concluímos que a caracterização enzimática de isolados de Candida pode ser um útil marcador prognóstico, especialmente em imunocomprometidos, uma vez que leveduroses nestes pacientes são geralmente graves.
Purpureocillium lilacinum is a filamentous and hyaline fungus cosmopolitan, saprophytic, largely used in the biological control of plant‐parasitic nematodes and insects, also considered an emerging and opportunistic human pathogen. The standard treatment for hyalohyphomycosis caused by P. lilacinum is not yet defined, since this fungus is resistant to different antifungals, in vitro and in vivo. The aim of this study was to evaluate and compare in vitro antifungal activity against environmental and clinical P. lilacinum isolates and our results demonstrated that these isolates can be resistant to newer generation triazoles, such as voriconazole, and to caspofungin, a drug of the echinocandin class. In summary, we highlight the importance of knowing the different susceptibility profiles of P. lilacinum isolates, and besides that, the emergence of uncommon human and animal opportunistic fungi, such P. lilacinum, especially during COVID‐19, highlight the need for antifungal susceptibility testing of isolates since empirical therapy with different treatment schedules failed in great number of patients.
Cryptococcosis is an infectious disease of worldwide distribution, caused by encapsulated yeasts belonging to the phylum Basidiomycota. The genus Cryptococcus includes several species distributed around the world. The C. gattii/neoformans species complex is largely responsible for most cases of cryptococcosis. However, clinical series have been published of infections caused by Papiliotrema (Cryptococcus) laurentii and Naganishia albida (Cryptococcus albidus), among other related genera. Here, we examined the pathogenic potential and antifungal susceptibility of C. gattii/neoformans species complex (clades I and II) and related genera (Papiliotrema and Naganishia) isolated from environmental and clinical samples. P. laurentii (clade III), N. liquefasciens/N. albidosimilis (clade IV); and N. adeliensis/N. albida (clade V) strains produced higher levels of phospholipase and hemolysins, whereas the C. gattii/neoformans species complex strains (clades I and II) had markedly thicker capsules, produced more biofilm biomass and melanin, which are known virulence attributes. Interestingly, 40% of C. neoformans strains (clade II) had MICs above the ECV established for this species to amphotericin B. Several non-C. gattii/neoformans species complex (clades III to V) had MICs equal to or above the ECVs established for C. deuterogattii and C. neoformans for all the three antifungal drugs tested. Finally, all the non-C. gattii/neoformans clinical isolates (clades III to V) produced more melanin than the environmental isolates might reflect their particularly enhanced need for melanin during in vivo protection. It is very clear that C. gattii/neoformans species complex (clades I and II) strains, in general, show more similar virulence phenotypes between each other when compared to non-C. gattii/neoformans species complex (clades III to V) isolates. These observations together with the fact that P. laurentii and Naganishia spp. (clades III to V) strains were collected from the outside of a University Hospital, identify features of these yeasts important for environmental and patient colonization and furthermore, define mechanisms for infections with these uncommon pathogens.
Background: Sporotrichosis occurs through contact with contaminated soil and plant. However, the incidence of sporotrichosis as a zoonotic epidemic has increased, particularly in Rio de Janeiro. Aim: In this work, we decided to evaluate some T-cell phenotypes involved in the immune response. Materials & methods: We used flow cytometry to quantify TCD4+ and TCD8+ and Treg from immunocompetent and immunosuppressed mice infected with Sporothrix species with different levels of virulence and pathogenicity. Results: It was demonstrated the predominance of TCD4+ over the TCD8+ cells in both groups, inoculated with all the species, and percentages of Treg observed in infected immunocompetent mice. Conclusion: This regulatory phenotype can be associated with a protective immunity in the initial periods of infection.
Caesalpinia pulcherrima is a species widely used in folk medicine for various diseases such as fever, infections and mouth ulcers. In addition, scientific studies have reported medicinal properties such as antitumor, antiviral, antibacterial and antifungal. Therefore, the objective of this work was to evaluate if organic extracts obtained from leaves of C. pulcherrima have medicinal properties. Three organic extracts were obtained (hexane, ethyl acetate and ethanol) from the leaves collected from the Soxhlet equipment. The characterization was made by GC-MS and UPLC-MS and biological properties as antioxidant (AAT, DPPH, ABTS and lipid peroxidation radicals), antimicrobial, cytotoxicity and immunostimulant (using splenocytes of mice Balb/c) were investigated. Results showed several classes of secondary metabolites, but the ethyl acetate showed more phenols and flavonoids than the other extracts. Extracts showed good results in antioxidant tests, especially the ethyl acetate, but did not show antibacterial activity. The fungal evaluation showed high antifungal properties, especially the hexanic and the ethyl acetate against Candida tropicalis, Aspergillus terreu, Candida krusei and Cryptococcus neoformans strains. Cytotoxicity evaluation showed that under 25 μg/mL are the safety doses that can be used for in vitro tests, besides that, extracts were able to induce cytokine stimulation. These results show that the ethyl acetate extract was the best formulation found in this study to be used against fungal infections, for antioxidant proposes and for promote immunostimulation.
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