In many gut chronic inflammatory conditions, intestinal epithelium (IE) is deprived of the protection of the mucus secreted by IE-specialized cells. In these events, bleeding and subsequent lysis of erythrocytes are common. This may lead to the release of high amounts of heme in the intestinal lumen, which interacts with IE. Previous works from our group have shown that heme itself is a proinfl...

Malaria parasite metabolizes hemoglobin and detoxifies the resulting toxic ferriprotoporphyrin IX by polymerization into a crystal insoluble pigment, known as hemozoin. A polymer identical to hemozoin, β-hematin, can be obtained in vitro from hematin at acidic pH. Quinoline-containing antimalarials (e.g. chloroquine) inhibit the formation of polymer. Thus, heme polymerization is an essensial an...

Horseradish peroxidase (HRP) mediates efficient conversion of many phenolic contaminants and thus has potential applications for pollution control. Such potentially important applications suffer however from the fact that the enzyme becomes quickly inactivated during phenol oxidation and polymerization. The work here provides the first experimental data of heme consumption and iron releases to ...

Thiol reagents react with cysteine beta 93 of hemoglobin and as a result increase the oxygen affinity of hemoglobin. In the present studies we have used a thiol-disulfide exchange between mixed disulfides of hemoglobin and reduced glutathione to attach intracellular glutathione to hemoglobin and to study its antisickling properties. The rates of production of glutathionyl hemoglobin (G-Hb) depe...

ethylene was polymerized in slurry phase over a ticl4/mg(oc2h5)2 catalyst activated by al(c2h5)3. it was shown experimentally that mass transfer resistance has no effect on polymerization kinetics. after estimation ofthe active site concentration by inhibition method with carbon monoxide, the effects of polymerization temperature, monomer and cocatalyst  oncentrations and hydrogen were investig...

The mechanism of action of artemisinin antimalarials may be ascribed to C-centered radicals that alkylate biomolecules or to the peroxide moiety, which inhibits a specific, as yet undefined, target (4). It is also proposed that artemisinins kill the parasite through inhibition of hemozoin formation, thereby allowing buildup of toxic heme monomer (1, 2, 5). Artemisinin and dihydroartemisinin may...

Cytochrome c (cyt c) is a stable protein that functions in a monomeric state as an electron donor for cytochrome c oxidase. It is also released to the cytosol when permeabilization of the mitochondrial outer membrane occurs at the early stage of apoptosis. For nearly half a century, it has been known that cyt c forms polymers, but the polymerization mechanism remains unknown. We found that cyt ...