The implantation of foreign material carries a risk of infection which frequently is resistant to all treatment short of removing the implant. We have previously shown that these materials activate neutrophils by contact, leading to production of oxygen free radicals accompanied by release of granule products. Such activation further results in depletion of local host defenses, including the ca...

Potential antioxidative activities of enzymatic extracts from seven species of brown seaweeds were evaluated using four different reactive oxygen species (ROS) scavenging assays containing DPPH (1,1-diphenyl-2-pricrylhydrazyl) free radical, superoxide anion, hydroxyl radical and hydrogen peroxide scavenging assay. The brown seaweeds were enzymatically hydrolyzed to prepare water-soluble extract...

A GROWING NUMBER of articles purport to demonstrate the importance of oxygen free radicals in a variety of pathophysiologic processes, including injury due to radiation, inflammation, and oxygen toxicity. The purpose of this essay is to examine the hypothesis that activated oxygen species may play a role in the extension of myocardial injury due to ischemia followed by reperfusion. Activated ox...

Endogenous and exogenous sources cause free radical-induced DNA damage in living organisms by a variety of mechanisms. The highly reactive hydroxyl radical reacts with the heterocyclic DNA bases and the sugar moiety near or at diffusion-controlled rates. Hydrated electron and H atom also add to the heterocyclic bases. These reactions lead to adduct radicals, further reactions of which yield num...

Chromophore-assisted laser inactivation (CALI) is a technique that selectively inactivates proteins of interest to elucidate their in vivo functions. This method has application to a wide array of biological questions and an understanding of its mechanism is required for its judicious application. We report here that CALI is not mediated by photoinduced thermal denaturation but by photogenerate...

Reactive oxygen species comprise oxygen-based free radicals and non-radical such as peroxynitrite electronically excited (singlet) oxygen. These reactive often have short lifetimes, much of our understanding their formation reactivity in biological especially medical environments has come from complimentary fast reaction methods involving pulsed lasers high-energy radiation techniques. related ...

BACKGROUND Oxygen supplementation is given routinely to parturients undergoing Caesarean section under regional anaesthesia. While the aim is to improve fetal oxygenation, inspiring a high oxygen fraction (FIO2) can also increase free radical activity and lipid peroxidation in both the mother and baby. In this prospective, randomized, double-blind study, we investigated the effect of high inspi...

In order to study the effect of omeprazole on the K/[H+] value of ascorbic acid (K = the ascorbic acid-ascorbic free radical equilibrium constant), changes of the concentration of ascorbate free radical in guinea pig sera were examined after intraperitoneal administration of omeprazole. Furthermore, to see the in vitro effect of omeprazole on ascorbate free radical, changes were examined in asc...

Oxygen free radicals are known to be generated during periods of ischemia followed by reperfusion. There is still some controversy, however, concerning the use of electron paramagnetic resonance spectroscopy to accurately detect and identify the free radical species that are formed. There is no doubt that oxygen radicals are deleterious to the myocardium; free radicals cause left ventricular dy...

background & aim: medicinal plants can be a good replacement for common cancer treatment including chemotherapy, radiation therapy and surgery because they don’t have many side effects. the aim of this study was to investigate the effect of temperature on the free radical scavenging in the presence of medicinal plants. experimental: for determination of free radical scavenging activity was...