Bruceine A

The title compound, C26H34O11, known as bruceine A, is a natural quassinoid extracted from the dried fruits of Brucea javanica. Its structure consists of five fused rings including an oxygen-containing heterocyclic ring and a lactone ring. Two intra­molecular O—H⋯O links help to establish the mol­ecular conformation. In the crystal, O—H⋯O hydrogen bonds connect the mol­ecules

Effect of the haematocrit layer geometry on Plasmodium falciparum static thin-layer in vitro cultures

<p>Abstract</p> <p>Background</p> <p><it>In vitro </it>cultivation of <it>Plasmodium falciparum </it>is usually carried out through the continuous preservation of infected erythrocytes deposited in static thin layers of settled haematocrit. This technique, called the candle-jar method, was first achieved by Trager and Jensen in 1976 and has undergone slight modifications since then. However, no systematic studies concerning the geometry of the haematocrit layer have been carried out. In this work, a thorough investigation of the effects of the geometric culturing conditions on the parasite's development is presented.</p> <p>Methods</p> <p>Several experimental trials exploring different settings have been carried out, covering haematocrit layer depths that ranged from 6 mm to 3 mm and separation between the walls of the culturing device that ranged from 7.5 mm to 9 mm. The obtained results have been analysed and compared to different system-level models and to an Individual-Based Model.</p> <p>Conclusion</p> <p>In line with the results, a mechanism governing the propagation of the infection which limits it to the vicinity of the interface between the haematocrit layer and the culture medium is deduced, and the most appropriate configurations are proposed for further experimental assays.</p

Deficient spontaneous cell-mediated cytotoxicity and lectin-induced cellular cytotoxicity by peripheral blood mononuclear cells from Thai adults naturally infected with malaria

To assess general cytotoxic effector cell capabilities by peripheral blood mononuclear cells from patients with active malaria infections, we examined antibody-dependent cellular cytotoxicity, spontaneous cell-mediated cytotoxicity, and lectin-induced cellular cytotoxicity by using human and chicken erythrocyte, Chang cell line, and K562 cell line targets. By using human erythrocyte and Change cell line targets, we found that Thai adults naturally infected with malaria had significantly impaired lectin-induced cellular cytotoxicity. In addition, spontaneous cell-mediated cytotoxicity was deficient with K562 but not with Chang cell line targets. Finally, no change in antibody-dependent cellular cytotoxicity was observed when chicken erythrocyte or Chang cell line targets were used. These observations, coupled with our previous observations of a physical loss of peripheral blood T cells, the presence of lymphocytotoxic serum antibodies, and defective T suppressor cell generation in patients with malaria, indicate that major alterations in the cellular immune system occur in patients with active malaria infections.</jats:p