Fusarium species have emerged as one of the more outstanding groups of clinically important filamentous fungi, causing localized and life-threatening invasive infections with high morbidity and mortality. The ability to produce different types of hydrolytic enzymes is thought to be an important virulence mechanism of fungal pathogens and could be associated with the environment of the microorganism. Here, we have measured the production of two distinct lipolytic enzymes, phospholipase and esterase, by sixteen Fusarium isolates recovered from the hospital environment, immunocompromised patients’ blood cultures, foot interdigital space scrapings from immunocompromised patients, and foot interdigital space scrapings from immunocompetent patients (4 isolates each). Fourteen of these 16 isolates were identified asFusarium solani species complex (FSSC) and two were identified as F. oxysporum species complex (FOSC). Some relevant genus characteristics were visualized by light and electron microscopy such as curved and multicelled macroconidia with 3 or 4 septa, microconidia, phialides, and abundant chlamydospores. All Fusarium isolates were able to produce esterase and phospholipase under the experimental conditions. However, a negative correlation was observed between these two enzymes, indicating that a Fusarium isolate with high phospholipase activity has low esterase activity and vice versa. In addition, Fusarium isolated from clinical material produced more phospholipases, while environmental strains produced more esterases. These observations may be correlated with the different types of substrates that these fungi need to degrade during their nutrition processes.

RESUMO Objetivo: O epitélio pigmentário da retina (EPR) desempenha um importante papel na resposta inflamatória ocular. "Transforming growth factor-beta" (TGF-β) e outros membros de sua superfamília têm sido descritos como reguladores de certas funções do EPR. Neste estudo, os autores investigaram a expressão de receptores da superfamília de TGF-β superfamily nas células do EPR a nível de RNA mensageiro. Métodos: Técnica de RT-PCR foi usada com RNA mensageiro de D407 (linhagem de células do EPR humano) e HaCatT (linhagem de queratócitos humanos usados como controle positivo). Resultados: A expressão de 6 receptores tipo I (TGF-β receptor tipo I, ALK-I, activina receptor tipo I, activina receptor tipo IB, BMP receptor tipo IA, BMP receptor tipo IB), e 4 receptores tipo II (TGF-β receptor tipo II, activina receptor tipo II, activina receptor tipo IIB, BMP receptor tipo II) foi investigada. Os resultados demonstraram que TGF-β, activinas e BMPs expressam receptores específicos a nível de RNA mensageiro em células do EPR. Conclusões: O presente estudo sugere que membros da superfamília de TGF-β podem exercer efeitos nas células de EPR D407 através de seus receptores específicos.

SUMMARY Background: Retinal pigment epithelial (RPE) cells play an important role in the inflammatory response of the eye. Trans-forming growth factor-beta (TGF-β) and other members of the TGF-β superfamily are described to regulate some RPE cells functions. In this study the expression of TGF-β superfamily receptors in RPE cells at mRNA level was investigated Methods: RT-PCR technique was performed using mRNAs from D407 RPE cells (human RPE cell line) and HaCatTcells (human keratinocyte cell line used as positive control). Results: Expression of 6 type 1 receptors (TGF-β type I receptor, ALK-1, Activin type I receptor, activin type IB receptor, BMP type SA receptor, BMP type IB receptor), and 4 type II receptors (TGF-β type lI receptor, activin type II receptor, activin type IIB receptor, BMP type II receptor) were studied. The results demonstrated that TGF-β, activins and BMPs express their own specific receptors at mRNA level. Conclusions: The present study suggests that TGF-β superfamily members can exert effects on D407 RPE cells through their specific receptors.