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Pyrazoles represent a significant class of heterocyclic compounds that exhibit pharmacological properties. The present study aimed to investigate the antioxidant potential of pyrazol derivative compounds in brain of mice in vitro and the effect of pyrazol derivative compounds in the oxidative damage and toxicity parameters in mouse brain and plasma of mice. The compounds tested were 3,5-dimethyl-1-phenyl-4-(phenylselanyl)-1H-pyrazol (1a), 3,5-dimethyl-4-(phenylselanyl)-1H-pyrazole (2a), 4-((4-methoxyphenyl)selanyl)-3,5-dimethyl-1-phenyl-1H-pyrazole (3a), 4-((4- chlorophenyl)selanyl)-3, 5-dimethyl-1-phenyl-1H-pyrazole (4a), 3,5-dimethyl-1-phenyl-4-(phenylthio)-1H-pyrazole (1b), 3,5-dimethyl-4- (phenylthio)-1H-pyrazole (2b), 4-((4-methoxyphenyl)thio)-3,5-dimethyl1-phenyl-1H-pyrazole (3b), 4-((4-chlorophenyl)thio)-3,5-dimethyl-1-phenyl-1H-pyrazole (4b), and 3,5- dimethyl-1-phenyl-1H-pyrazole (1c). In vitro, 4-(arylcalcogenyl)-1H-pyrazoles, at low molecular range, reduced lipid peroxidation and reactive species in mouse brain homogenates. The compounds also presented ferric-reducing ability as well nitric oxide-scavenging activity. Especially compounds 1a, 1b, and 1c presented efficiency to 1,1-diphenyl-2-picryl-hydrazyl-scavenging activity. Compounds 1b and 1c presented 2,20 -azinobis(3-ethylbenzthiazoline-6- sulfonic acid)-scavenging activity. In vivo assays demonstrated that compounds 1a, 1b, and 1c (300 mg/kg, intragastric, a single administration) did not cause alteration in the of [delta]-aminolevulinic acid dehydratase activity, an enzyme that exhibits high sensibility to prooxidants situations, in the brain, liver, and kidney of mice. Compound 1c reduced per se the lipid peroxidation in liver and brain of mice. Toxicological assays demonstrate that compounds 1a, 1b, and 1c did not present toxicity in the aspartate aminotransferase, alanine aminotransferase, urea, and creatinine levels in the plasma. In conclusion, the results demonstrated the antioxidant action of pyrazol derivative compounds in in vitro assays. Furthermore, the results showed low toxicity of compounds in in vivo assays. Key words: antioxidant, organoselenium, oxidative stress, toxicity, pyrazoles. Les pyrazoles representent une importante classe de composes heterocycliques dotes de proprietes pharmacologiques. La presente etude portait sur le potentiel antioxydant de composes derives des pyrazoles dans le cerveau de souris in vitro et sur l'effet des composes derives des pyrazoles sur les parametres des dommages et de la toxicite lies a l'oxydation dans le cerveau et le plasma de souris. Les composes evalues etaient les suivants : 3,5-dimethyl-1-phenyl-4-(phenylselanyl)-1H-pyrazole (1a), 3,5-dimethyl-4-(phenylselanyl)-1H-pyrazole (2a), 4-((4-methoxyphenyl)selanyl)- 3,5-dimethyl-1-phenyl-1H-pyrazole (3a), 4-((4chlorophenyl)selanyl)-3,5-dimethyl- 1-phenyl-1H-pyrazole (4a), 3,5-dimethyl-1-phenyl-4-(phenylthio)-1H-pyrazole (1b), 3,5-dimethyl-4-(phenylthio)-1H-pyrazole (2b), 4-((4-methoxyphenyl)thio)-3,5- dimethyl-1-phenyl-1H-pyrazole (3b), 4-((4-chlorophenyl)thio)-3,5-dimethyl-1-phenyl-1H-pyrazole (4b) et 3,5-dimethyl-1-phenyl-1H-pyrazole (1c). In vitro, les 4- (arylcalcogenyl)1H-pyrazoles, dans des proportions moleculaires faibles, entrainaient une diminution des taux de peroxydation lipidique et de derives reactifs dans des homogenats de cerveaux de souris. Les composes presentaient aussi une capacite de reduction ferrique, ainsi que de piegeage de l'oxyde nitrique. En particulier, les composes 1a, 1b et 1c affichaient une activite de piegeage efficace du 1,1-diphenyl-2-picryl-hydrazyle. Les composes 1b et 1c affichaient une activite de piegeage du 2,20-azino-bis (3-ethylbenzthiazoline-6-acide sulfonique). Les epreuves in vivo ont montre que les composes 1a, 1b et 1c (a 300 mg/kg, avec administration unique par voie intragastrique) n'ont pas entraine de diminution de l'activite de la dehydratase de l'acide [delta]-aminolevulinique, une enzyme qui presente une sensibilite elevee en situation de pro-oxydation, dans le cerveau, le foie et les reins de souris. Le compose 1c entrainait intrinsequement une diminution de la peroxydation lipidique dans le cerveau et le foie de souris. Les epreuves toxicologiques montrent que les composes 1a, 1b et 1c ne presentent pas de toxicite quant a l'aspartate aminotransferase et a l'alanine aminotransferase ainsi qu'aux taux d'uree et de creatinine dans le plasma. En conclusion, les resultats ont montre l'activite antioxydante de composes derives des pyrazoles dans le cadre d'epreuves in vitro. En outre, les resultats ont montre la faible toxicite des composes dans le cadre d'epreuves in vivo. Mots-des : antioxydant, organoselenium, stress oxydatif, toxicite, pyrazoles., Introduction Pyrazole, a five-membered ring structure composed of three carbon atoms and two nitrogen atoms in adjacent positions (Fig. 1), is reported to possess a wide range of biological activities [...]

Lead is a major environmental pollutant that causes serious adverse effects on biological systems and cells. In this study, we examined the effect of citicoline on lead-induced apoptosis in PC12 cells. The PC12 cells were pre-treated with citicoline and then exposed to lead for 48 h. The effect of citicoline on cell survival was examined by MTT assay. In addition, levels of lipid peroxidation (LPO), total thiol groups, total antioxidant power (TAP), catalase (CAT), superoxide dismutase (SOD), and reduced glutathione (GSH) were evaluated. The levels of Bax, Bcl-2, and caspase-3 were also measured, by Western blot analysis. Citicoline significantly increased the cell viability of PC12 cells exposed to lead. Treatment of PC12 cells with lead increased LPO levels, and citicoline effectively decreased LPO. Levels of total thiol groups and TAP, CAT, SOD, and GSH were significantly increased in citicoline-treated PC12 cells compared with the lead-treated group. Citicoline pretreatment significantly reduced Bax expression, and increased the level of Bcl-2 expression. Citicoline also reduced caspase-3 activation in PC12 cells compared with the lead-treated group. Our findings indicate that citicoline exerts a neuroprotective effect against lead-induced injury in PC12 cells through mitigation of oxidative stress and, at least in part, through suppression of the mitochondria-mediated apoptotic pathway. Key words: lead toxicity, oxidative stress, apoptosis, PC12 cells, citicoline. Le plomb est un polluant environnemental important qui provoque plusieurs effets indesirables graves sur les systemes biologiques et les cellules. Dans cette etude, les auteurs ont examine l'effet de la citicoline sur l'apoptose induite par le plomb chez les cellules PC12. Les cellules PC12 ont ete pretraitees a la citicoline puis exposees au plomb pendant 48 h. L'effet de la citicoline sur la survie cellulaire a ete examine par un dosage au MTT. De plus, la peroxydation lipidique (LPO), les thiols totaux, le potentiel antioxydant total (PAT), la catalase (CAT), la superoxyde dismutase (SOD) et le glutathion reduit (GSH) ont ete mesures. Les niveaux de Bax, de Bcl-2 et de la caspase-3 ont aussi ete mesures par buvardage de western. La citicoline pouvait accroitre significativement la viabilite des cellules PC12 exposees au plomb. Le traitement des cellules PC12 au plomb augmentait la LPO alors que la citicoline diminuait efficacement la LPO. Les thiols totaux ainsi que le PAT, la CAT, la SOD et le GSH etaient significativement accrus chez les cellules PC12 traitees a la citicoline comparativement au groupe traite au plomb. Le pretraitement a la citicoline reduisait significativement l'expression de Bax et augmentait le niveau d'expression de Bcl-2. La citicoline reduisait aussi l'activation de la caspase-3 dans les cellules PC12 comparativement au groupe traite au plomb. Les donnees des auteurs ont revele que la citicolin exerce des effets neuroprotecteurs envers les dommages induits par le plomb chez les cellules PC12 par l'attenuation du stress oxydant et du moins en partie, par la suppression de la voie mitochondriale de l'apoptose. [Traduit par la Redaction] Mots-cles : toxicite du plomb, stress oxydant, apoptose, cellules PC12, citicoline., Introduction Lead toxicity is a major health concern for public and health care worldwide. Exposure to lead can cause serious adverse effects on various body systems such as the hematopoietic [...]

Byline: M. M. Hasan, H. F. Alharby, A. S. Hajar, K. R. Hakeem and Y. Alzahrani ABSTRACT Drought stress is one of the major abiotic stresses and serious problem for [...]

Some antioxidant anesthetics directly inhibit lipid peroxidation mediated via the generation of reactive oxygen species (ROS). To date, the scavenging effects of midazolam on ROS have not been directly assessed. We investigated the inhibitory effect of midazolam on ROS [hydroxyl radical (H[O.sup.*]) and superoxide ([O.sup.*-.sub.2]-)] by in vitro X-band electron spin resonance with the spin-trapping agent 5,5-dimethyl-1-pyrroline-N-oxide. Our results indicated that H[O.sup.*] and [O.sup.*-.sub.2] were not affected by midazolam at clinically relevant concentrations, but were directly scavenged by midazolam at high concentrations (i.e., >4.6 and >1.5 mM, respectively). Keywords Reactive oxygen species--Oxidative stress Electron spin resonance (ESR)--Antioxidants--Midazolam, Various reports have shown that oxidative stress induced by reactive oxygen species (ROS) such as the hydroxyl radical (H[O.sup.*]) and superoxide ([O.sup.*-.sub.2]) can contribute to the pathophysiology of brain diseases, [...]

Geranylgeranyl reductase from Sulfolobus acidocaldarius was shown to catalyze the reduction of geranylgeranyl groups in the precursors of archaeal membrane lipids, generally reducing all four double bonds. However, when geranylgeranyl diphosphate was subjected to the reductase reaction, only three of the four double bonds were reduced. Mass spectrometry and acid hydrolysis indicated that the allylic double bond was preserved in the partially reduced product derived from geranylgeranyl diphosphate. Thus, the reaction product was shown to be phytyl diphosphate, which is a substrate for archaeal prenyltransferases, unlike the completely reduced compound phytanyl diphosphate.

Green tea, rich in antioxidant and anti-inflammatory catechins, especially epigallocatechin gallate (EGCG), has been shown to reduce surrogate markers of atherosclerosis and lipid peroxidation, particularly LDL oxidation and malondialdehyde concentrations, in several in vitro, animal, and limited clinical studies. Epidemiological observations in Southeast Asian countries indicate an inverse correlation exists between habitual consumption of green tea beverages and the incidence of cardiovascular events. A few short-term clinical studies have reported its effects in attenuating biomarkers of oxidative stress and inflammation among smokers, and an ability to decrease postprandial lipemia in hypercholesterolemic subjects has also been suggested. However, further investigations are needed to confirm the potential role of green tea beverages and the safety of green tea supplements in reducing body fat, as well as other biomarkers of cardiovascular disease risks. Key words: epigallocatechin gallate, green tea, lipid peroxidation, smokers, weight loss doi: 10.1301/nr.2007.aug.361-375

Conventional numerical electromagnetic methods are known to provide accurate means of characterizing wireless channel transfer functions. However, their practical utilization is hampered by their typically large computational cost compared to empirical, measurement-based or ray-tracing techniques. In this paper, a full-wave, time-domain technique, stemming from the spatial expansion of electromagnetic field components in smooth, spline-type basis functions, is shown to provide a rigorous, yet efficient tool for site-specific indoor channel modeling. Based on this method, wireless propagation across indoor channel geometries can be accurately characterized and signal fading statistics can be extracted. Numerical examples, indicating the significantly improved efficiency of the proposed approach, compared to the standard finite-difference time-domain method, are given. Moreover, important wave propagation effects on indoor channel performance, readily accounted for by our full-wave analysis, are demonstrated. Index Terms--Fading properties, finite-difference time-domain (FDTD), multiresolution time-domain (MRTD), scaling-functionbased multiresolution time-domain (S-MRTD), time-domain full-wave electromagnetic modeling, wireless channel.

High intakes of whole grain foods are inversely related to the incidence of coronary heart diseases and type 2 diabetes, but the mechanisms remain unclear. Our study aimed to evaluate the effects of a diet rich in whole grains compared with a diet containing the same amount of refined grains on insulin sensitivity and markers of lipid peroxidation and inflammation. In a randomized crossover study, 22 women and 8 men (BMI 28 [+ or -] 2) were given either whole-grain or refined-grain products (3 bread slices, 2 crisp bread slices, 1 portion muesli, and 1 portion pasta) to include in their habitual daily diet for two 6-wk periods. Peripheral insulin sensitivity was determined by euglycemic hyperinsulinemic clamp tests. 8-Iso-prostaglandin [F.sub.2[alpha]] (8-iso PG[F.sub.2[alpha]]), an [F.sub.2]-isoprostane, was measured in the urine as a marker of lipid peroxidation, and highly sensitive C-reactive protein and IL-6 were analyzed in plasma as markers of inflammation. Peripheral insulin sensitivity [mg glucose * kg body [wt.sup.-1] * [min.sup.-1] per unit plasma insulin (mU/L) x 100] did not improve when subjects consumed whole-grain products (6.8 [+ or -] 3.0 at baseline and 6.5 [+ or -] 2.7 after 6 wk) or refined products (6.4 [+ or -] 2.9 and 6.9 [+ or -] 3.2, respectively) and there were no differences between the 2 periods. Whole-grain consumption also did not affect 8-iso-PG[F.sub.2[alpha]] in urine, IL-6 and C-reactive protein in plasma, blood pressure, or serum lipid concentrations. In conclusion, substitution of whole grains (mainly based on milled wheat) for refined-grain products in the habitual daily diet of healthy moderately overweight adults for 6-wk did not affect insulin sensitivity or markers of lipid peroxidation and inflammation.

The regeneration of a series of 2,3-dihydrobenzo[b]selenophene-5-ol derivatives by water-soluble N-acetylcysteine in a two-phase model system for lipid peroxidation is investigated. The results have shown that the regeneration and catalytic performance is dictated by the number and position of methyl substituents present in the phenolic ring of the antioxidant.

Objective Advanced glycoxidation end products (AGEs), the derivatives of glucose-protein or glucose-lipid interactions, are implicated in the complications of diabetes and aging. The objective of this article was to determine the AGE content of commonly consumed foods and to evaluate the effects of various methods of food preparation on AGE production. Design Two-hundred fifty foods were tested for their content in a common AGE marker [.sup.[epsilon]]N-carboxymethyllysine (CML), using an enzyme-linked immunosorbent assay based on an anti-CML monoclonal antibody. Lipid and protein AGEs were represented in units of AGEs per gram of food. Results Foods of the fat group showed the highest amount of AGE content with a mean of 100[+ or -]19 kU/g. High values were also observed for the meat and meat-substitute group, 43[+ or -]7 kU/g. The carbohydrate group contained the lowest values of AGEs, 3.4[+ or -]1.8 kU/g. The amount of AGEs present in all food categories was related to cooking temperature, length of cooking time, and presence of moisture. Broiling (225[degrees]C) and frying (177[degrees]C) resulted in the highest levels of AGEs, followed by roasting (177[degrees]C) and boiling (100[degrees]C). Conclusions The results indicate that diet can be a significant environmental source of AGEs, which may constitute a chronic risk factor for cardiovascular and kidney damage. J Am Diet Assoc. 2004;104:1287-1291.

The antioxidant effect of [beta]-carotene was investigated in an emulsified linoleic acid model system with or without exposure to light. The effect of tocopherol on the antioxidant action of [beta]-carotene was also investigated. The antioxidant effect of [beta]-carotene was significant, and synergistically increased by the addition of rac [alpha]-tocopherol, in the dark but not in the light. It was confirmed that superoxide anions ([O.sup.-.sub.2]) and hydrogen peroxide ([H.sub.2][O.sub.2]) were formed during the light exposure, and that their formation could be significantly inhibited by the addition of tryptophan or mannitol, scavenger of hydroxyl radicals. These results strongly suggest direct participation of hydroxyl radicals, formed via the Haber-Weiss reaction, in the emulsified linoleic acid model system, with [beta]-carotene inhibition in the dark but an increase in the light. Regarding the mechanism of the antioxidant effect of [beta]-carotene, when [beta]-carotene is oxidized, the hydroperoxide in the acts as an electron acceptor and the hydroperoxide itself then decomposes.

Research shows that porcine leukocyte 12-lipoxygenase selectively oxygenates 2-arachidonylglycerol in vitro and in vivo indicating that the enzyme participates in the endogenous cannabinoid system.

Increased membrane lipid peroxidation causes copper toxicity in Saccharomyces cerevisiae. The ability of the cells to cope with copper is compromised by induction of antioxidant defenses during respiratory adaptation and by membrane fatty acids. These findings are of great significance in the study of the environment because the fatty acid levels of microorganisms show great variation.

A high-performance liquid chromatographic method has been developed to measure adlehyde products of lipid peroxidation including n-alkenals, trans-2-alkenals, 4-hydroxy-2-nonenal, and malonaldehyde. The chromophoric reagent dabsylhydrazine reacts with various aldehydes produced from two different lipid peroxidation model systems: [Fe.sup.2+]/[H.sub.2][O.sub.2] and [Fe.sub.3+]/vitamin C oxidation of arachidonic and linoleic acids, respectively. The formed products were carefully characterized by IR, MS, and NMR spectral analysis and proved to be hydrazone rather than 2-pyrazoline or pyrrole derivatives. EI-MS of all the derivatized straight-chain aldehydes showed a characteristic (M - 28) fragment in the spectra with high consistency. Physicochemical properties including melting points are also described. The detection limits in the range of 11 pmol (5 ng) have been reached by using an NP Octadecyl [C.sub.18] reversed-phase column. 4-Hydroxy-2-nonenal and hexanal were found to be the most abundant aldehydes in the livid peroxidation systems described. The dose - response curve showed great linearity and exhibited good reproducibility of this procedure for quantitative estimation.

Iron complexes (Fe(PMA))n+ (n = 1, 2) are synthetic analogues of iron bleomycin (BLM) and in the presence of oxygen or H2O2, these analogues promote lipid peroxidation. Spectroscopic data detect the presence of a low-spin (hydroperoxo)iron(III) species as intermediates in the lipid peroxidation. Reaction of these model complexes with linoleic acid and arachidonic acid results in 13-OOH and 15-OOH positional isomers, respectively

Sensory evaluation of cooked and 4 degrees Celsius stored pork from fifteen crossbred pigs fed with 131, 62 or 209 ppm iron content-based corn-soy diet reveals that 200 ppm iron content elevates lipid oxidation, nonheme iron (NHI) levels and thiobarbituric acid reactive substance (TBARS) but has no effect on warmed-over aroma (WOA). However, during storage NHI, WOA and TBARS exhibit a correlation and increase to high levels, suggesting that NHI and TBARS are reliable indicators of WOA in pork.

Manganese peroxidase-mediated lipid peroxidation of linolenic acid is involved in the oxidation of phenanthrene to 2,2'-diphenic acid by intact fungal cultures of Phanerochaete chrysosporium. The oxidation requires Mn(II), oxygen and unsaturated lipids and occurs in the same rate as in vitro oxidation activated by Mn.

Studies of an NADH-dependent lipid peroxidation system from channel catfish muscle microsomes reveal its functional nature at -10 degrees Celsius, below which inhibition occurs. The storage temperature is inversely related to subsequent peroxidase activity following thawing. When stored at -10 degrees Celsius, the fish fillets exhibit decreased fatty acid levels.

The estimation of lipid oxidation in meat is facilitated by spectrophotometric evaluation of the malonaldehydethiobarbituric acid, TBA, complex. TBA test involves direct heating of the sample meat in the presence of TBA, and subsequent isolation of the red pigment by centrifugation. The sample is distilled and its distillate is subjected to reaction with TBA. A comparative analysis evaluates the efficiency and specificity of an aqueos acid extraction TBA-C18 method when compared to other TBA tests. The correlation between the sensory analysis of rancid odor and TBA numbers of the other four TBA methods, is also tested.

The different stimulants and suppressors of enzymic lipid peroxidation in channel catfish muscle microsomes were studied. Natural antioxidants, alpha-tocopherol, beta-carotene, rosemary powder, sodium ascorbate and erythorbate were subjectedto lipid peroxidation experiments and mineral composition analysis. Phenolic antioxidants were found to be the most effective enzymic peroxidation system for frozen catfish.