Antibody response to Plasmodium vivax in the context of Epstein-Barr virus (EBV) co-infection: A 14-year follow-up study in the Amazon rainforest.

Background: To develop an effective vaccine against Plasmodium vivax, the most widely dispersed human malaria parasite, it is critical to understand how coinfections with other pathogens could impact malaria-specific immune response. A recent conceptual study proposed that Epstein-Barr virus (EBV), a highly prevalent human herpesvirus that establishes lifelong persistent infection, may influence P. vivax antibody responses.

Impact of Epstein-Barr virus co-infection on natural acquired Plasmodium vivax antibody response.

Background: The simultaneous infection of Plasmodium falciparum and Epstein-Barr virus (EBV) could promote the development of the aggressive endemic Burkitt's Lymphoma (eBL) in children living in P. falciparum holoendemic areas. While it is well-established that eBL is not related to other human malaria parasites, the impact of EBV infection on the generation of human malaria immunity remains largely unexplored.

Antibody response to a new member of the DBL family (EBP2) after a brief Plasmodium vivax exposure.

Plasmodium vivax blood-stage invasion into reticulocyte is critical for parasite development. Thus, validation of novel parasite invasion ligands is essential for malaria vaccine development. Recently, we demonstrated that EBP2, a Duffy binding protein (DBP) paralog, is antigenically distinct from DBP and could not be functionally inhibited by anti-DBP antibodies.

Antiplasmodial and cytotoxic effects of the methanol extract, canthinone alkaloids, squalene- and protolimonoid-type triterpenes from Homalolepis suffruticosa roots.

Ethnopharmacological Relevance: Different species of the Simaroubaceae family are used in traditional medicine to treat malaria. Among these is Homalolepis suffruticosa (syn. Simaba suffruticosa and Quassia suffruticosa), which is native to Central Brazil and popularly known as calunga.

In vitro antiplasmodial activity, targeted LC-MS metabolite profiling, and identification of major natural products in the bioactive extracts of Palicourea and Psychotria species from the Amazonia and Atlantic Forest biomes, Brazil.

Introduction: A great variety of bioactive natural products has been reported for different Palicourea and Psychotria species (Rubiaceae). However, few of them as well as few of species of these botanical genera have been evaluated for antiplasmodial activity.

Objective: To assess the antiplasmodial activity of 24 extracts from Palicourea and Psychotria genera, along with the targeted LC-MS metabolite profiling, as well as identification of the main metabolites in the bioactive extracts.

In silico, in vitro and in vivo evaluation of natural Bignoniaceous naphthoquinones in comparison with atovaquone targeting the selection of potential antimalarial candidates.

The natural naphthoquinones lapachol, α- and β-lapachone are found in Bignoniaceous Brazilian plant species of the Tabebuia genus (synonym Handroanthus) and are recognized for diverse bioactivities, including as antimalarial. The aim of the present work was to perform in silico, in vitro and in vivo studies to evaluating the antimalarial potential of these three naphthoquinones in comparison with atovaquone, a synthetic antimalarial. The ADMET properties of these compounds were predicted in silico by the preADMET program.

Bioprospection for antiplasmodial activity, and identification of bioactive metabolites of native plants species from the Mata Atlântica biome, Brazil.

A total of 33 extracts of eleven different plants species from Mata Atlântica biome, Brazil, and different fractions of the bioactive extracts were evaluated against chloroquine-resistant W2 strain by LDH method and cytotoxicity to HepG2 cells by the MTT assay, and chemically characterized by LC-DAD-ESI-MS/MS analysis. The results allowed the identification of and as the most active plant species. Different flavonoids and tannins in and besides alkaloids in were identified.

Phytochemistry and antiplasmodial activity of leaves.

Aiming to investigate the antiplasmodial activity and the phytochemical composition of leaves, the essential oil and dichloromethane extract were analyzed by gas and liquid chromatography, respectively, both of them coupled to mass spectrometry, and were evaluated against the chloroquine-resistant strain (W2) and for cytotoxicity to HepG2 cells. Low growth inhibition of as well as low cytotoxicity to HepG2 cells were observed for the essential oil. The leaves dichloromethane extract showed moderate growth inhibition of and low cytotoxicity to HepG2 cells.

Antiplasmodial activity and cytotoxicity, isolation of active alkaloids, and dereplication of Xylopia sericea leaves ethanol extract by UPLC-DAD-ESI-MS/MS.

Objectives: To assess the antiplasmodial activity of the ethanol extract of Xylopia sericea leaves, Annonaceae, often associated with antimalarial use and to perform a bioguided isolation of active compounds.

Methods: Dereplication of ethanol extract by the UPLC-DAD-ESI-MS/MS technique allowed the identification of the major constituents, isolation and identification of alkaloids. The antiplasmodial and cytotoxic activity of the extract, fractions and isolated compounds was evaluated against the chloroquine-resistant W2 strain Plasmodium falciparum and HepG2 cells, respectively.

In vitro antiplasmodial activity and identification, using tandem LC-MS, of alkaloids from Aspidosperma excelsum, a plant used to treat malaria in Amazonia.

Ethnopharmacological Relevance: Aspidosperma excelsum Benth. (Apocynaceae), a native tree in the Brazilian Amazonia, is traditionally used to treat various diseases, including malaria.

Aim Of Study: To investigate the chemical constitution, antiplasmodial activity and cytotoxicity of samples obtained from A.

Synthesis, SAR, and Docking Studies Disclose 2-Arylfuran-1,4-naphthoquinones as Antiplasmodial Hits.

A total of 28 lapachol-related naphthoquinones with four different scaffolds were synthesized and spectroscopically characterized. antiplasmodial activity was assayed against the chloroquine-resistant W2 strain by the parasite lactate dehydrogenase (LDH) method. Cytotoxicity against Hep G2A16 cell was determined by the MTT assay.

7-Chloroquinolinotriazoles: synthesis by the azide-alkyne cycloaddition click chemistry, antimalarial activity, cytotoxicity and SAR studies.

Twenty-seven 7-chloroquinolinotriazole derivatives with different substituents in the triazole moiety were synthesized via copper-catalyzed cycloaddition (CuAAC) click chemistry between 4-azido-7-chloroquinoline and several alkynes. All the synthetic compounds were evaluated for their in vitro activity against Plasmodium falciparum (W2) and cytotoxicity to Hep G2A16 cells. All the products disclosed low cytotoxicity (CC50 > 100 μM) and five of them have shown moderate antimalarial activity (IC50 from 9.

Spleen cell proliferation during and after skin myiasis by human bot fly Dermatobia hominis.

Spleen cells from mice were examined at 5, 10, 15, 20 and 25 days post-infection (dpi) with Dermatobia hominis larva and at 5, 10, 15, 30 and 60 days post-larval emergence (dple). Cell proliferation in vitro assays were carried out with RPMI-1640 medium and larval secretory product (LSP) of D. hominis at 5, 10, 15, 20 and 25 days.