Publications by authors named "Igor Correia de Almeida"

Article Synopsis
  • Parasites cause many neglected tropical diseases, affecting over a billion people and leading to millions of deaths each year.
  • Recent research shows that tiny particles called extracellular vesicles (EVs) from these parasites help them survive by interacting with host cells and spreading drug resistance.
  • The paper suggests better methods to study these EVs, including how to collect and understand them from infected people and animals, and talks about different tests that can be done in host cells.
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, the aetiologic agent of Chagas disease, releases vesicles containing a wide range of surface molecules known to affect the host immunological responses and the cellular infectivity. Here, we compared the secretome of two distinct strains (Y and YuYu) of , which were previously shown to differentially modulate host innate and acquired immune responses. Tissue culture-derived trypomastigotes of both strains secreted extracellular vesicles (EVs), as demonstrated by electron scanning microscopy.

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Thromboembolic events were described in patients with Chagas disease without cardiomyopathy. We aim to confirm if there is a hypercoagulable state in these patients and to determine if there is an early normalization of hemostasis factors after antiparasitic treatment. Ninety-nine individuals from Chagas disease-endemic areas were classified in two groups: G1, with T.

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Background: The surface coat of Trypanosoma cruzi is predominantly composed of glycosylphosphatidylinositol-anchored proteins, which have been extensively characterized. However, very little is known about less abundant surface proteins and their role in host-parasite interactions.

Methodology/ Principal Findings: Here, we described a novel family of T.

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The definition of a biomarker provided by the World Health Organization is any substance, structure, or process that can be measured in the body, or its products and influence, or predict the incidence or outcome of disease. Currently, the lack of prognosis and progression markers for chronic Chagas disease has posed limitations for testing new drugs to treat this neglected disease. Several molecules and techniques to detect biomarkers in Trypanosoma cruzi-infected patients have been proposed to assess whether specific treatment with benznidazole or nifurtimox is effective.

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TLR2 plays a critical role in the protection against Paracoccidioides brasiliensis conferred by ArtinM administration. ArtinM, a D-mannose-binding lectin from Artocarpus heterophyllus, induces IL-12 production in macrophages and dendritic cells, which accounts for the T helper1 immunity that results from ArtinM administration. We examined the direct interaction of ArtinM with TLR2using HEK293A cells transfected with TLR2, alone or in combination with TLR1 or TLR6, together with accessory proteins.

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When indirect hemagglutination, indirect immunofluorescence and enzyme-linked immunosorbent assay are used together for serologically diagnosing Chagas disease, results that are considered discordant sometimes occur because there is disagreement between what these tests indicate. The availability of the chemiluminescent ELISA method enabled tests on 200 serum samples that had previously produced discordant results from the three above-mentioned methods. CL-ELISA revealed that 193 of these samples were negative and seven were positive.

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Histone tails provide sites for a variety of post-translational modifications implicated in the control of gene expression and chromatin assembly. As both histones and control of gene expression in trypanosomes are highly divergent compared to most eukaryotes, post-translational modifications of Trypanosoma cruzi histones were investigated. After in vivo incubation of live parasites with radiolabeled precursors, histone H4 mainly incorporates [(3)H]-acetyl, and to a lesser extent [(3)H]-methyl residues.

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