Showing papers in "Free Radical Biology and Medicine in 1991"

TL;DR: This review provides a comprehensive summary on the chemical properties of 4-hydroxyalkenals and malonaldehyde, the mechanisms of their formation and their occurrence in biological systems and methods for their determination, as well as the many types of biological activities described so far.

TL;DR: Overall, studies of glycation and protein browning suggest a critical role for oxidative processes perhaps involving decompartmentalized transition metals and a variety of low molecular weight reducing agents in diabetes mellitus and ageing.

TL;DR: D-Alpha-tocotrienol possesses 40-60 times higher antioxidant activity against (Fe2+ + ascorbate)- and (Fe1+ + NADPH)-induced lipid peroxidation in rat liver microsomal membranes and 6.5 times better protection of cytochrome P-450 against oxidative damage than d-alpha-tocopherol.

TL;DR: The sensitivity and selectivity of the GC/MS-SIM technique enables the measurement of DNA base products even in isolated mammalian chromatin without the necessity of first isolating DNA, and despite the presence of histones.

TL;DR: The lack of clear evidence for the occurrence of lipid peroxidation or antioxidant function of vitamin E in vivo can be attributed partly to the presence of active pathways for metabolizing hydroperoxides, aldehydes, and other oxidation products.

TL;DR: Liver and heart homogenates were subjected to in vitro oxidative stresses such as supplementation with organic hydroperoxide or with enzymatic systems generating superoxide anion or hydrogen peroxide and chemiluminescence was higher in the poststress samples than in the control ones.

TL;DR: The interactions of radical intermediates with target biomolecules should lead to the development of relevant biomarkers of these interactions as well as rational chemoprotective strategies with antioxidants or other radical detoxifiers for the prevention of neoplasia.

TL;DR: The induction of HSP70 appears to be a physiological response to the heat shock and oxidative stress of exercise, and it is found that muscle mitochondria undergo progressive uncoupling and increased O2- generation with increasing temperatures.

TL;DR: It is proposed that the noninvasive measurement of oh8dG in urine can be used to estimate in vivo oxidative damage, a biomarker of oxidative DNA damage that is formed from hydroxyl radical attack of guanine residues in DNA.

TL;DR: Iron, lipid peroxidation, peroxidase, catalase, superoxide dismutase, and glutathione levels in the brain, and various theories of induction of Parkinson's disease are discussed in relation to the possible involvement of oxygen radicals.

TL;DR: It is shown that the presence of hydroxyl groups in the B ring of flavonoids is essential for their scavenger activity, and the existence of a hydroxYL at C-3 enhances the scavenger ability of Flavonoids.

TL;DR: In this paper, a series of carotenoids such as beta-carotene were exposed to either spontaneous autoxidation conditions or to radical-initiated autoxification conditions.

TL;DR: One of the greatest needs in the field of free radical biology is the development of reliable methods for measuring oxidative stress status (OSS) in humans.

TL;DR: A review of the disparate AOE responses of the neonatal versus adult animal in hyperoxia explores other possible explanations for the striking O2 tolerance of young versus adult animals, including comparative O2 free radical production rates, inflammatory cell responses, lung lipid composition, repair capabilities, etc.

TL;DR: Lipid radicals also played some role in protein damage in these systems, and BSA could inhibit the peroxidation of liposomes induced by AAPH and less efficiently that induced by AMVN.

TL;DR: It appears that free radicals and lipid peroxidation are involved in the etiology of diabetic retinopathy in the STZ rat model and may prove useful in diagnosis and monitoring of patients with diabetes.

TL;DR: It is found that ozonations of emulsions of fatty acids containing from one to four double bonds give one mole of H2O2 for each mole of ozone reacted, which agrees with expectations.

TL;DR: Pharmacologic investigation of vitamin E (and synthetic, vitamin E-like antioxidants) in nutritional and hyperlipidemic animal models of spontaneous atherosclerosis is required to establish whether any atherosclerotic impact is associated with vitamin E and, if so, what the mechanistic basis of the therapeutic benefit is.

TL;DR: Rat liver microsomal lipids in hexane solution were exposed to the lipid-soluble radical initiator, azobis-isobutyronitrile (AIBN), and the antioxidant activities of α-tocopherol and β-carotene have been compared.

TL;DR: Evidence suggesting a relationship of lipid peroxidation to breast cancer risk is described, and the method used to generate this information might usefully be applied to other disease states are proposed, and some suggestions for further work are made.

TL;DR: Peroxidatic metabolism of benzene's phenolic metabolites may be responsible for the increased free radical activity and toxicity produced by benzene in bone marrow.

TL;DR: After a single exposure to doses ranging from 0.05 to 0.50 Gy, the SOD activities in immune organs of the irradiated rats, at 4 h after whole-body X irradiation, showed significant increases by 50 to 90% in comparison with the control groups.

TL;DR: No such bioactive compound has been found as a metabolite of the 12- and 15-lipoxygenase pathways, and their physiological roles are still unclarified.

TL;DR: Analysis by sodium dodecyl sulphate polyacrylamide gel electrophoresis revealed that besides apolipoprotein B-100 there was evidence of peptides with a higher molecular weight in LDL-.(ABSTRACT TRUNCATED at 250 WORDS)

TL;DR: Results suggest that quantification of these prostanoids may provide a new approach to assess oxidative stress in vivo in humans.

TL;DR: It is found that spermine inhibits the cytochrome C reduction initiated by FMLP- or PMA-stimulated human granulocytes and inhibits the Fe(III)/xanthine oxidase stimulated lipid peroxidation of brain phospholipid liposomes, suggesting that sPermine has at least two antioxidative mechanisms of action.

TL;DR: Results suggest 21-aminosteroid-induced changes in the molecular packing order and drug: fluorescent probe interactions in membrane hydrophobic (or lipid) domains throughout the BMEC.

TL;DR: The hypothesis that GSH and GST provide a biologically significant pathway for protection against aldehydic by-products of lipid peroxidation is supported.