Paracoccidioides brasiliensis yeast cells can enter mammalian cells and may manipulate the host cell environment to favour their own growth and survival. Moreover, fibronectin and several other host extracellular matrix proteins are recognized by various components of the yeast cell extracts. The present study was designed to isolate and characterize a fibronectin-binding protein from P. brasiliensis. We also compared P. brasiliensis strain 18, tested before (Pb18a) and after (Pb18b) animal passage, in relation to its adhesion and invasion processes. Extracts from both samples, when cultured on blood agar solid medium, showed higher levels of protein expression than when the same samples were cultured on Fava-Netto solid medium, as demonstrated by twodimensional electrophoresis and SDS-PAGE. Also, both Pb18a and Pb18b exhibited stronger adhesion to A549 epithelial cells when cultured on blood agar medium than when cultured on Fava-Netto medium. Ligand affinity binding assays revealed a protein of 54 kDa and pI 5.6 in P. brasiliensis cell-free extracts with the properties of a fibronectin-binding adhesin, which was characterized by tryptic digestion and mass spectroscopy as a homologue of enolase from P. brasiliensis. Antibody raised against this 54 kDa protein abolished 80 % of P. brasiliensis adhesion to A549 epithelial cells. Our results demonstrate that P. brasiliensis produces a fibronectin-binding adhesin, irrespective of the culture medium, and that this activity can be inhibited by a specific antibody and is involved in the adhesion of the fungus to pulmonary epithelial cells.

Host-fungal interactions are inherently complex and dynamic. In order to identify new microbial targets and develop more effective antifungal therapies, it is important to understand the cellular and molecular mechanisms of disease. Paracoccidioidomycosis provokes a variety of clinical symptoms, and Paracoccidioides brasiliensis can reach many tissues, but primarily attacks the lungs.

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Paper-based devices are an excellent match for low-cost point-of-care testing (POCT) tools. Their userfriendliness, portability, and short time of analysis, coupled with ease of local manufacture make these devices the best option for inexpensive diagnostic testing tools. However, despite all their positive features, these low-cost diagnostic devices must present good performance indicators, such as sensitivity, specificity, and accuracy. We developed and validated a paper-based ELISA for toxoplasmosis diagnosis through the detection of Toxoplasma gondii immunoglobulin G (IgG) antibodies in 100 human serum samples. From among the different ways to define the cut-off value, we chose Youden's J index (cut-off ¼ 21.73 A.U.), which presented a higher sensitivity value. Our paper-based assay presented a sensitivity of 0.96, a specificity of 0.87, and a gray zone comprising 16 samples (AE15% of the cut-off value, with 3 false positive outputs). The accuracy of the test was estimated by using ROC curves (AUC ¼ 0.97). We also created a macro in Microsoft Excel® to estimate the accuracy of the test (m-Accuracy) based on a non-parametric method, which evidenced a value ¼ 0.88, which classifies our test as moderately to highly accurate. We also provide the m-Accuracy macro for download and the paperbased microplate designs for printing, in order to collaborate with the scientific community and facilitate further studies using this platform. The improvement of these diagnostic tools can bring this technology for those who need it, contributing to population health and well-being.

Osteopontin (OPN) is an extracellular matrix protein implicated in bone remodeling, but it presents also pro-inflammatory and pro-fibrotic properties. OPN expression also occurs upon exposure of cells to classical mediators of acute inflammation such as tumor necrosis growth factor alpha (TNF-alpha) and interleukin-1 beta (IL-1beta), as well as fibrogenic cytokines such as transforming growth factor beta (TGF-beta), although a detailed understanding of these regulatory pathways is still unknown. Plasma OPN levels in both limited and diffuse systemic sclerosis patients (lSSc and dSSc) were statistically higher compared to those of control subjects. Immunohistology demonstrated that high TGF-beta levels, alpha smooth muscle actin (alphaSMA) levels and consequently high OPN levels were found in the affected skin of sclerodermic patients (lSSc and dSSc) compared to levels found in healthy skin. In order to better understand how OPN interferes with the fibrotic process, healthy skin fibroblasts were treated for 24 and 48 hours with bleomycin and with endothelin-1 (ET-1) plus TGF-beta in order to induce the fibrogenesis. After 48 hours of stimulation, healthy treated fibroblasts showed statistically increased alphaSMA levels (index of differentiation into myofibroblasts) and simultaneously statistically increased OPN levels compared to healthy untreated ones. This study demonstrates that OPN levels increase simultaneously with the increasing of alphaSMA levels, therefore it is reasonable to hypothesize that OPN interferes in the pathogenesis of Systemic Sclerosis in the early stage of fibroblast differentiation process.

Bats are important for the homeostasis of ecosystems and serve as hosts of various microorganisms including bacteria, viruses, and fungi with pathogenic potential. This study aimed to isolate fungi from biological samples obtained from bats captured in the city of Sinop (state of Mato Grosso, Brazil), where large areas of deforestation exist due to urbanization and agriculture. On the basis of the flow of people and domestic animals, 48 bats were captured in eleven urban forest fragments. The samples were processed and submitted to microbiological cultures, to isolate and to identify the fungal genera. Thirty-four (70.83%) of the captured bats were positive for fungi; 18 (37.5%) and 16 (33.33%) of these bats were female and male, respectively. Penicillium sp., Scopulariopsis sp., Fusarium sp., Aspergillus sp., Alternaria sp., Cryptococcus sp., Trichosporon sp., and Candida sp., which may cause opportunistic infections, were isolated. The bat species with the highest number of fungal isolates was Molossus molossus: 21 isolates (43.8%). According to our results, bats captured in urban forest fragments in Sinop harbor pathogenic fungi, increasing the risk of opportunistic fungal infections in humans and domestic animals.

ABSTRACT

Dermatomycoses, which comprise dermatophytosis, candidosis and pityriasis versicolor, affect the most vulnerable populations, represent one of the most common infectious diseases worldwide and cause serious chronic morbidity. 1 Currently, these diseases affect 20%-25% of the world population, but their incidence continues to increase. 2 Dermatophytes, yeasts and non-dermatophytes are etiological agents of dermatomycoses. 1 Superficial and cutaneous mycoses can be detected in skin, hair, nails, mucosa and cutaneomucosal zones due to colonisation of the keratinised layers of the body. They can be extremely contagious,