The phenotypic plasticity of Cryptococcus neoformans is widely studied and demonstrated in vitro, but its influence on pathogenicity remains unclear. In this study, we investigated the dynamics of cryptococcal cell and transcriptional remodeling during pulmonary infection in a murine model. We showed that in Cryptococcus neoformans, cell size reduction (cell body ≤ 3 µm) is important for initial adaptation during infection.
View Article and Find Full Text PDFExtracellular vesicles (EVs) has been considered an alternative process for intercellular communication. EVs release by filamentous fungi and the role of vesicular secretion during fungus-host cells interaction remain unknown. Here, we identified the secretion of EVs from the pathogenic filamentous fungus, .
View Article and Find Full Text PDFAntimicrob Agents Chemother
May 2018
The clinical pathogen is a relevant cause of nosocomial infections, and resistance to current treatment with carbapenem antibiotics is becoming a significant problem. Statins are inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) used for controlling plasma cholesterol levels. There is clinical evidence showing other effects of statins, including decrease of lung inflammation.
View Article and Find Full Text PDFAntimicrob Agents Chemother
August 2017
Human cryptococcosis can occur as a primary or opportunistic infection and develops as an acute, subacute, or chronic systemic infection involving different organs of the host. Given the limited therapeutic options and the occasional resistance to fluconazole, there is a need to develop novel drugs for the treatment of cryptococcosis. In this report, we describe promising thiazole compounds 1, 2, 3, and 4 and explore their possible modes of action against To this end, we show evidence of interference in the antioxidant system.
View Article and Find Full Text PDFTrichophyton rubrum is the main etiological agent of dermatophytosis, an infection of the skin that affects millions of people worldwide. In this study, we developed a murine model of the dermatophytosis caused by T. rubrum in which C57BL/6 wild-type, interleukin (IL)-12(-/-), and interferon-gamma (IFN-γ(-/-)) mice were inoculated with 1 × 10(6) conidia/animal.
View Article and Find Full Text PDFLeukotrienes (LTs) produced from arachidonic acid by the action of 5-lipoxygenase (5-LO) are classical mediators of inflammatory responses. However, studies published in the literature regarding these mediators are contradictory and it remains uncertain whether these lipid mediators play a role in host defense against the fungal pathogen Paracoccidioides brasiliensis. To determine the involvement of LTs in the host response to pulmonary infection, wild-type and LT-deficient mice by targeted disruption of the 5-lipoxygenase gene (knockout mice) were studied following intratracheal challenge with P.
View Article and Find Full Text PDFObjectives: Although the most accepted mechanisms of action of amphotericin B and azoles are related to ergosterol, it is possible that these drugs have other effects on the fungal cell. In the present study, the role of endogenous reactive oxygen species (ROS) and peroxynitrite produced by azoles and amphotericin B in the fungus Cryptococcus gattii were examined.
Methods: We studied distinct parameters to evaluate the effect of oxidative and nitrosative stresses induced by these drugs in C.
Objectives: Antimicrobial photodynamic inhibition (aPI) is based on the use of a light source and a photosensitizer to kill pathogens. Little is known about aPI of dermatophytic fungi and its mechanism of action. We aimed to evaluate aPI of Trichophyton rubrum.
View Article and Find Full Text PDFCryptococus gattii is an emergent primary human pathogen that causes meningismus, papilledema, high intracranial pressure and focal involvement of the central nervous system in immunocompetent hosts. Prolonged antifungal therapy is the conventional treatment, but it is highly toxic, selects for resistant strains, contributes to therapy failure and has a poor prognosis. Photodynamic inactivation (PDI) offers a promising possibility for the alternative treatment of cryptococcosis.
View Article and Find Full Text PDFThe presence of Cryptococcus gattii was investigated in different regions of the State of Espírito Santo. The largest number (73) of samples was collected from trees located in public places in Vitória; 47 came from preserved areas or areas with only minor human impact, surrounding this city, at altitudes from 0 to 900m above sea level; 48 came from trees native of the northern and southern regions of the state. The samples were collected from tree hollows and trunks by of swabs and yielded two isolates (1.
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