Publications by authors named "Silvia H M Da Silva"

Article Synopsis
  • The Herpotrichiellaceae family consists of pathogenic fungi linked to diseases like chromoblastomycosis and phaeohyphomycosis, which present complex clinical symptoms and are found globally.
  • Identifying these fungi is difficult due to subjective morphological methods, leading researchers to rely on molecular techniques, particularly genetic sequencing of ribosomal DNA.
  • This study developed optimized PCR-Multiplex methodologies to improve the identification of these fungi, aiming to enhance infection management and provide more accurate epidemiological data.
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Chromoblastomycosis (CBM) and phaeohyphomycosis (FEO) are infections caused by melanized filamentous fungal agents, primarily found in tropical and subtropical regions. Both infections pose significant challenges for the correct identification of the causative agent due to their morphological similarity, making conventional methods of morphological analysis highly subjective. Therefore, molecular techniques are necessary for the precise determination of these species.

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The essential oils of three specimens of (A, B and C) and were extracted by hydrodistillation, and the chemical compositions from the essential oils were identified by gas chromatography and flame ionization detection (CG/MS and CG-FID). The fungicide potential of the EOs against five fungicide yeasts was assessed: INCQS-40175, ATCC 6258, ATCC 62894, ATCC 13803 and IEC-01. The essential oil of the specimen (A) was characterized by the major compounds: α-bulnesene (26.

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Aim: Development of functionalized nanocomposites containing AgNPs-PVP-Glucantime to evaluate their leishmanicidal activity as a novel method for improving the pharmacological properties of the drug Glucantime against extracellular promastigotes and intracellular amastigotes of Leishmania amazonensis in vitro to treat cutaneous leishmaniasis.

Materials & Methods: The silver nanoparticles and nanocomposites prepared containing silver nanoparticles, polyvinylpyrrolidone and different amounts of Glucantime were characterized using transmission electron microscopy, x-ray diffraction, energy-dispersive x-ray spectroscopy and ζ potential analysis; in addition, the in vitro cytotoxicity was evaluated.

Results: The nanocomposites showed an inhibitory effect on the cellular viability of promastigote forms, with values of 47.

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Chemical composition of the methanol extract of Myrciaria floribunda leaves was investigated. The nor-lupane triterpenoids platanic acid and messagenic I acid were identified, along with other known triterpenoids (betulinic aldehyde, ursolic acid acetate and betulinic acid), a new lupane triterpenoid (2α,6α,30-trihydroxybetulinic acid) and the flavonoids catechin, quercetrin and mirycitrin. The structures were determined by spectroscopic methods (NMR, LC-MS, GC-MS).

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Article Synopsis
  • Paracoccidioidomycosis (PCM) is a serious fungal infection prevalent in Latin America, presenting diagnostic challenges due to limitations in current methods.
  • A new latex immunoassay using sensitized latex particles (SLPs) targeting the gp43 antigen shows high sensitivity (98.46%) and specificity (93.94%) for detecting antibodies in PCM patients, and can also identify antigens in those with immune deficiencies.
  • This rapid, cost-effective diagnostic test could significantly improve PCM detection and monitoring in clinical settings, potentially leading to commercialization.
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Cryptococcus neoformans is an important cause of morbidity in HIV-infected patients worldwide. In the northern region of Brazil, the prevalence of this infection is poorly known due to a lack of systematic investigations. This study aimed to determine the occurrence of cryptococcosis by detecting antigenaemia in HIV-infected patients in the State of Para, Brazil.

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Neuroparacoccidioidomycosis (neuroPCM) is the central nervous system infection by the fungus Paracoccidioides brasiliensis. Its diagnosis is a difficult task that depends on neuroimaging techniques such as computed tomography and magnetic resonance imaging. However, the detection of circulating P.

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The main objectives of this study were to obtain clones of Paracoccidioides brasiliensis by two methods (micromanipulation and plating assay) and to determine if the secretion of the 43-kDa glycoprotein (gp43) is dependent on the clonal culture. The results show that the secretion of gp43 is not dependent on clonal cultures. Clones that originally were secretors of this molecule, after subculturing, lost this characteristic; on the other hand, clones that originally did not secrete gp43 began to secrete gp43 after subculturing.

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Paracoccidioidomycosis (PCM), one of the most important systemic mycoses in Central and South America, is caused by the dimorphic fungus Paracoccidioides brasiliensis and has a high prevalence in Brazil. Glycoproteins of 43 and 70 kDa are the main antigenic compounds of P. brasiliensis and are recognized by Western blotting by 100 and 96% of PCM patient sera, respectively.

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