Cultured rat embryonic cortical neurons undergo apoptosis when treated with the topoisomerase-I inhibitor camptothecin. Pharmacological or molecular caspase inhibition prevents apoptosis, but the neurons still die in a delayed nonapoptotic manner. Here we examine the mechanisms leading to such caspase-independent death, focusing on events related to mitochondrial malfunction, which accompanies ...

High performance liquid chromatography with TSK 5000 PW or TSK 6000 PW size exclusion columns combined with a 125I labelled hyaluronic acid binding protein assay was used to study the effects of oxygen derived free radicals on synovial fluid hyaluronate. A continuous flux of free radicals was generated by the xanthine oxidase/hypoxanthine system. When the free radical flux was generated with xa...

The overproduction of reactive oxygen species (ROS) and reactive nitrogen species (RNS) is a common underlying mechanism of many neuropathologies, as they have been shown to damage various cellular components, including proteins, lipids and DNA. Free radicals, especially superoxide (O(2)*-), and non-radicals, such as hydrogen peroxide (H(2)O(2)), can be generated in quantities large enough to o...

Radical-induced degradation of proton exchange membranes limits the durability proton-exchange membrane fuel cells. Cerium is widely used as a radical scavenger, but migration cerium ions to the...

OBJECTIVE Amniotic membrane (AM) is used to manage various debilitated ocular surface conditions. The impact of oxidative stress and free radicals on the ocular surface is increasingly being recognized. Hyaluronic acid (HA) has anti-inflammatory properties and is abundantly present in AM. In this in vitro pilot study, we investigated the potential of AM for intrinsic free radical scavenging pro...

Arsenite, the trivalent form of arsenic present in the environment, is a known human carcinogen that lacked mutagenic activity in bacterial and standard mammalian cell mutation assays. We show herein that when evaluated in an assay (AL cell assay), in which both intragenic and multilocus mutations are detectable, that arsenite is in fact a strong dose-dependent mutagen and that it induces mostl...

The thermal decomposition of tert-butyl-1,3-cyclopentadiene has been investigated in single-pulse shock-tube studies at shock pressures of 182-260 kPa and temperatures of 996-1127 K. Isobutene (2-methylpropene), 1,3-cyclopentadiene, and toluene were observed as the major stable products in the thermolysis of dilute mixtures of the substrate in the presence of a free-radical scavenger. Hydrogen ...

The free radical scavenging activity of Trolox was studied for aqueous and lipid environments using the Density Functional Theory. Several reaction mechanisms and free radicals of different chemical nature have been included in this study, as well as the influence of the pH. Trolox was found to be a powerful ˙OH and alkoxy scavenger, regardless of the conditions under which the reaction takes p...