Search results for "Plasmodium"
showing 10 items of 86 documents
Joziknipholones A and B: The First Dimeric Phenylanthraquinones, from the Roots ofBulbine frutescens
2007
From the roots of the African plant Bulbine frutescens (Asphodelaceae), two unprecedented novel dimeric phenylanthraquinones, named joziknipholones A and B, possessing axial and centrochirality, were isolated, together with six known compounds. Structural elucidation of the new metabolites was achieved by spectroscopic and chiroptical methods, by reductive cleavage of the central bond between the monomeric phenylanthraquinone and -anthrone portions with sodium dithionite, and by quantum chemical CD calculations. Based on the recently revised absolute axial configuration of the parent phenylanthraquinones, knipholone and knipholone anthrone, the new dimers were attributed to possess the P-co…
Rotenoids, Flavonoids, and Chalcones from the Root Bark of Millettia usaramensis.
2015
Five new compounds, 4-O-geranylisoliquiritigenin (1), 12-dihydrousararotenoid B (2), 12-dihydrousararotenoid C (3), 4'-O-geranyl-7-hydroxyflavanone (4), and 4'-O-geranyl-7-hydroxydihydroflavanol (5), along with 12 known natural products (6-17) were isolated from the CH2Cl2/MeOH (1:1) extract of the root bark of Millettia usaramensis ssp. usaramensis by chromatographic separation. The purified metabolites were identified by NMR spectroscopic and mass spectrometric analyses, whereas their absolute configurations were established on the basis of chiroptical data and in some cases also by X-ray crystallography. The crude extract was moderately active (IC50 = 11.63 μg/mL) against the ER-negative…
Naphthalene Derivatives from the Roots of Pentas parvifolia and Pentas bussei
2016
The phytochemical investigation of the CH2Cl2/MeOH (1:1) extract of the roots of Pentas parvifolia led to the isolation of three new naphthalenes, parvinaphthols A (1), B (2), and C (3), two known anthraquinones, and five known naphthalene derivatives. Similar investigation of the roots of Pentas bussei afforded a new polycyclic naphthalene, busseihydroquinone E (4), a new 2,2'-binaphthralenyl-1,1'-dione, busseihydroquinone F (5), and five known naphthalenes. All purified metabolites were characterized by NMR and MS data analyses, whereas the absolute configurations of 3 and 4 were determined by single-crystal X-ray diffraction studies. The E-geometry of compound 5 was supported by DFT-base…
Mbandakamine-Type Naphthylisoquinoline Dimers and Related Alkaloids from the Central African Liana Ancistrocladus ealaensis with Antiparasitic and An…
2018
Four new dimeric naphthylisoquinoline alkaloids, michellamine A5 (2) and mbandakamines C–E (4–6), were isolated from the Congolese plant Ancistrocladus ealaensis, along with the known dimer mbandakamine A (3). They represent constitutionally unsymmetric dimers, each consisting of two 5,8′-coupled naphthylisoquinoline monomers. While the molecular halves of michellamine A5 (2) are linked via C-6′ of both of the naphthalene moieties, i.e., via the least-hindered positions, so that the central biaryl axis is configurationally unstable and not an additional element of chirality, the mbandakamines 3–6 possess three consecutive stereogenic axes. Their monomeric units are linked through an unprece…
In Vitro and In Vivo Antimalarial Activity Assays of Seeds from Balanites aegyptiaca: Compounds of the Extract Show Growth Inhibition and Activity ag…
2011
Balanites aegyptiaca(Balanitaceae) is a widely grown desert plant with multiuse potential. In the present paper, a crude extract fromB. aegyptiacaseeds equivalent to a ratio of 1 : 2000 seeds to the extract was screened for antiplasmodial activity. The determined IC50value for the chloroquine-susceptiblePlasmodium falciparumNF54 strain was 68.26 . Analysis of the extract by gas chromatography-mass spectrometry detected 6-phenyl-2(H)-1,2,4-triazin-5-one oxime, an inhibitor of the parasitic M18 Aspartyl Aminopeptidase as one of the compounds which is responsible for thein vitroantiplasmodial activity. The crude plant extract had a of 2.35 and showed a dose-dependent response. After depletion…
Antileukemic ancistrobenomine B and related 5,1′-coupled naphthylisoquinoline alkaloids from the Chinese liana Ancistrocladus tectorius
2017
A striking feature of the metabolite pattern of the Southeast Asian liana Ancistrocladus tectorius (Ancistrocladaceae) is the predominance of 5,1′-coupled naphthylisoquinoline alkaloids. About 20 alkaloids of this coupling type have so far been discovered in this plant species. Here, we report on the isolation of four new 5,1′-linked naphthylisoquinolines from the twigs and stems of A. tectorius. Two of them, the ancistrobenomines B (5) and C (6), belong to the very rare group of alkaloids with a fully dehydrogenated isoquinoline portion. Likewise unusual for naphthylisoquinoline alkaloids is the presence of a hydroxymethylene group at C-3. Within the large class of meanwhile ca. 180 such n…
Biology of gama delta T Cells in Tuberculosis and Malaria
2002
Tuberculosis and malaria remain the leading causes of mortality among human infectious diseases in the world. It is estimated that 3 to 5 million people die from tuberculosis and malaria each year. Although it is traditionally believed that CD4 and CD8 alphabeta T lymphocytes are mandatory for protective immune responses against Mycobacterium tuberculosis and Plasmodium falciparum (the ethiologic agents of tuberculosis and the most severe form of malaria, respectively), there is still incomplete understanding of the mechanisms of immune protection and of the causes of its failure in the affected patients. Several studies in humans and animal models have suggested that Vgamma9/Vdelta2 T cell…
Plasmodium falciparumMalaria: Reduction of Endothelial Cell Apoptosis In Vitro
2005
ABSTRACTOrgan failure inPlasmodium falciparummalaria is associated with neutrophil activation and endothelial damage. This study investigates whether neutrophil-induced endothelial damage involves apoptosis and whether it can be prevented by neutralization of neutrophil secretory products. Endothelial cells from human umbilical veins were coincubated with neutrophils from healthy donors and with sera from eight patients withP. falciparummalaria, three patients withP. vivaxmalaria, and three healthy controls. Endothelial apoptosis was demonstrated by terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) and annexin V staining. The rate of apoptosis of cells was …
Acalculous cholecystitis in a patient with plasmodium falciparum malaria and cytomegalovirus infection
2017
Acalculous cholecystitis is a syndrome of gallbladder inflammation without gallstones, recognized within the setting of critically ill patients. Acalculous cholecystitis associated with infectious agents is reported in the literature to be rare. Herein we describe a case of acalculous cholecystitis in a patient with malaria caused by Plasmodium falciparum and apparent cytomegalovirus infection, and discuss the possible role of CMV in the pathogenesis of acalculous cholecystitis in patients with malaria.
Malaria and the heart: Two rare case reports of plasmodium falciparum-associated pericarditis
2017
Malaria is one of the most important parasitic diseases in the world, causing significant mortality and morbidity in the tropical regions1 . Although symptoms can range from a mild fever to severe complicated forms, there are limited published data on cardiac involvement of malaria and only a few studies have been carried out regarding cardiac function in severe malaria2–3. Cardiac involvement in the course of malaria ranges from severe forms with hypatension, shock, circulatory collapse and impaired haemodynamic function, to mild disorders documented by Electrocardiogram (ECG) and echocardiography4–6. Pericardial involvement in malaria is a very rare event7–8. We report here two cases of f…