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High Oxidative Stress (high + oxidative_stress)
Selected AbstractsHigh Oxidative Stress Is Correlated with Frailty in Elderly ChineseJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 9 2009I-Chien Wu MD OBJECTIVES: To evaluate the relationship between oxidative stress and frailty in elderly people. DESIGN: Cross-sectional study. SETTING: Community and hospital-based outpatient clinic. PARTICIPANTS: Ninety participants aged 65 and older. MEASUREMENTS: Frailty status was determined according to the presence of weak handgrip strength, weight loss, slow walking speed, exhaustion, and low activity level and was classified as frail (,3 criteria), prefrail (1 or 2 criteria), or robust (0 criteria). An oxidative stress marker (serum 8-hydroxy-2,-deoxyguanosine, 8-OHdG), metabolic markers (body mass index, waist,hip ratio, serum lipids, glucose, and albumin), an inflammatory marker (serum high-sensitivity C-reactive protein, hs-CRP), demographic information, and comorbidities (diabetes mellitus, hypertension, congestive heart failure, osteoarthritis, overweight or obesity, impaired fasting plasma glucose, renal insufficiency, and depression) were assessed. RESULTS: Of the 90 participants, 21 (23.3%) were frail, 56 (62.2%) were prefrail, and 13 (14.4%) were robust. Frail subjects had higher median (range) serum 8-OHdG (2.5 ng/mL (1.5,6.2 ng/mL) vs 2.3 ng/mL (0.5,8.1 ng/mL) and 1.0 ng/mL (0.5,5.3 ng/mL)) and serum hs-CRP (2.5 mg/L (0.3,32.1 mg/L) vs 1.8 mg/L (0.3,50.5 mg/L) and 1.7 mg/L (0.3,4.0 mg/L)) levels, lower mean±standard deviation serum albumin levels (4.1±0.4 g/dL vs 4.4±0.4 g/dL and 4.6±0.2 g/dL) and higher mean waist,hip ratios (0.96±0.11 vs 0.91±0.07 and 0.89±0.05)) than prefrail and robust subjects, respectively (P<.05 for all). In multivariable regression analysis, high serum 8-OHdG level was still significantly associated with frailty after adjusting for age, smoking status, comorbidities, waist,hip ratio, serum albumin level, and hs-CRP level. CONCLUSION: High oxidative stress, characterized by high serum 8-OHdG level, was independently associated with frailty in the selected sample of elderly Chinese. [source] Influence of oxidative stress and grains on sclerotial biomass and carotenoid yield of Penicillium sp.JOURNAL OF BASIC MICROBIOLOGY, Issue 4 2010Abstract Oxidative stress and grains were evaluated for carotenoid production by solid-state fermentation using Penicillium sp. PT95. When the fungus was grown at high oxidative stress, its sclerotial biomass and carotenoid content in sclerotia increased significantly with respect to low oxidative stress (P < 0.01). High oxidative stress also caused a statistically significant increase in carotenoid yield as compared with low oxidative stress (P < 0.01). Both the sclerotial biomass and the amount of carotenoid accumulated in sclerotia of strain PT95 were strongly dependent on the grain medium used. Among the grain media tested under high oxidative stress, buckwheat medium gave the highest content of carotenoid in sclerotia (828 ,g/g dry sclerotia), millet medium gave respectively the highest sclerotial biomass (12.69 g/100 g grain) and carotenoid yield (10.152 mg/100 g grain). (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Resistance to oxidative stress caused by ceftazidime and piperacillin in a bio,lm of PseudomonasLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 5 2004Paola C. Battán Abstract The capacity to form a bio,lm was evaluated in Pseudomonas aeruginosa isolated from patients with lung and urinary infections. Adherence, development of microcolonies and slime formation varied in the studied strains. P. aeruginosa P63 isolated from cystic ,brosis (CF) exhibited important microcolony formation with the densest bio,lm, and was selected to study the oxidative stress produced with ceftazidime and piperacillin by means of chemiluminescence (CL) in cell suspensions and bio,lm. P. aeruginosa strain P63 was compared with P69; both were sensitive to ceftazidime and showed increase of reactive species of oxygen (ROS) in the presence of this antibiotic. P. aeruginosas P69 exhibited resistance to piperacillin and low ROS production, while piperacillin-sensitive strain P63 showed high oxidative stress with this antibiotic. Piperacillin stimulated oxidative stress, increasing ROS production only in the sensitive strain. Higher antibiotic concentrations were necessary to augment ROS in bacteria bio,lm than in suspension. Incubation of P63 strain with ceftazidime or piperacillin in the presence of its own extracellular matrix (EM) or sodium alginate stimulated lesser oxidative stress and slower decrease of ROS than in the absence of these polysaccharides. A variant, V10, obtained from strain P63 showed more sensitivity to the antibiotics than the wild-type, and concomitantly exhibited higher production of ROS in the presence of both the antibiotics studied. Copyright © 2004 John Wiley & Sons, Ltd. [source] Oxidative stress, endothelial function and coenzyme Q10BIOFACTORS, Issue 1-4 2008Romualdo Belardinelli Abstract Reactive oxygen species seem to play an important role in vascular homeostasis. In conditions of high oxidative stress, such as chronic heart failure and multiple coronary risk factors, the rate of inactivation of nitric oxide to peroxynitrite by superoxide anions may be reduced by CoQ10, which can also protect against nitrosative damage. CoQ10 may also influence vascular function indirectly via inhibition of oxidative damage to LDL. Patients with lower levels of extracellular superoxide dismutase (ecSOD) demonstrate greater improvements than patients with normal ec-SOD levels, suggesting that the higher the oxidative stress the greater the improvement in the endothelium-dependent relaxation after the administration of a compound with antioxidant properties like CoQ10. Future studies are needed to inquire whether these effects may translate into benefits in clinical practice. [source] | ||||||||||