Purification and characterization of a low-temperature hydroxylamine oxidase from heterotrophic nitrifier Acinetobacter sp. Y16 / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To purify a low-temperature hydroxylamine oxidase (HAO) from a heterotrophic nitrifying bacterium Acinetobacter sp. Y16 and investigate the enzyme property.</p><p><b>METHODS</b>A HAO was purified by an anion-exchange and gel-filtration chromatography from strain Y16. The purity and molecular mass were determined by RP-HPLC and SDS-PAGE. The HAO activity was detected by monitoring the reduction of potassium ferricyanide using hydroxylamine as substrate and ferricyanide as electron acceptor. The partial amino acid sequence was determined by mass spectrometry.</p><p><b>RESULTS</b>The low-temperature HAO with a molecular mass of 61 kDa was purified from strain Y16 by an anion-exchange and gel-filtration chromatography. The enzyme exhibited an ability to oxidize hydroxylamine in wide temperature range (4-40 °C) in vitro using hydroxylamine as substrate and ferricyanide as electron acceptor. It was stable in the temperature range of 4 to 15 °C and pH range of 6.0 to 8.5 with less than 30% change in its activity. The optimal temperature and pH were 15 °C and 7.5, respectively. Three peptides were determined by mass spectrometry which were shown to be not identical to other reported HAOs.</p><p><b>CONCLUSION</b>This is the first study to purify a low-temperature HAO from a heterotrophic nitrifier Acinetobacter sp. It differs from other reported HAOs in molecular mass and enzyme properties. The findings of the present study have suggested that the strain Y16 passes through a hydroxylamine-oxidizing process catalyzed by a low-temperature HAO for ammonium removal.</p>

Increased oxidative stress and damage in patients with chronic bacterial prostatitis / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate whether chronic bacterial prostatitis (CBP) increases oxidative stress and damage in patients with CBP, and to explore its possible mechanism.</p><p><b>METHODS</b>Eighty patients with CBP and 80 healthy adults as controls were enrolled in a case-control study, in which levels of nitric oxide (NO), vitamin C (VC), and vitamin E (VE) in plasma, as well as malondialdehyde (MDA), activities of superoxide dismutase (SOD), and catalase (CAT) in erythrocytes were determined by spectrophotometry.</p><p><b>RESULTS</b>Compared with the average values of NO, VC, VE, MDA, SOD, and CAT in the healthy control group, those of plasma NO and erythrocyte MDA in the CBP group were significantly increased (P < 0.001), and those of plasma VC and VE as well as erythrocyte SOD and CAT in the CBP group were significantly decreased (P < 0.001). Findings from partial correlation analysis for course of the disease and NO, VC, VE, MDA, SOD, and CAT in 80 patients with CBP, adjusted for age, suggested that with prolonged course of the disease, values of NO and MDA were gradually increased (P < 0.001), and those of VC, VE, SOD, and CAT were gradually decreased (P < 0.05-0.001). The findings from stepwise regression analysis for course of the disease and NO, VC, VE, MDA, SOD, and CAT in CBP group suggested that the model of stepwise regression was Y = -19.1160 + 0.3112MDA + 0.0337NO, F = 22.1734, P < 0.001, r = 0.6045, P < 0.001. The findings from the reliability analysis for VC, VE, SOD, CAT, NO, and MDA in the CBP group showed that the reliability coefficients' alpha (6 items) was 0.7195, P < 0.0001, and the standardized item alpha was 0.9307, P < 0.0001.</p><p><b>CONCLUSION</b>There exist increased oxidative stress and damage induced by chronic bacterial prostatitis in patients, and such a phenomenon is closely related to the course of disease.</p>

Increased oxidative stress and oxidative damage associated with chronic bacterial prostatitis / 亚洲男科学杂志(英文版)

<p><b>AIM</b>To investigate whether chronic bacterial prostatitis might increase oxidative stress and oxidative damage in chronic bacterial prostatitis patients (CBPP), and to explore its possible mechanism.</p><p><b>METHODS</b>Enrolled in a case-control study were 70 randomly sampled CBPP and 70 randomly sampled healthy adult volunteers (HAV), on whom plasma nitric oxide (NO), vitamin C (VC), vitamin E (VE) and beta-carotene (beta-CAR) level, erythrocyte malondialdehyde (MDA) level, as well as erythrocyte superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) activities were determined by spectrophotometry.</p><p><b>RESULTS</b>Compared with the HAV group, values of plasma NO and erythrocyte MDA in the CBPP group were significantly increased (P < 0.001); those of plasma VC, VE and beta-CAR as well as erythrocyte SOD, CAT and GPX activities in the CBPP group were significantly decreased (P < 0.001). Findings from partial correlation for the 70 CBPP showed that with prolonged course of disease, values of NO and MDA were gradually increased (P < 0.001), and those of VC, VE, beta-CAR, SOD, CAT and GPX were gradually decreased (P < 0.05-0.001). The findings from stepwise regression for the 70 CBPP suggested that the model was Y = -13.2077 + 0.1894MDA + 0.0415NO - 0.1999GPX, F = 18.2047, P < 0.001, r = 0.6729, P < 0.001.</p><p><b>CONCLUSION</b>The findings suggest that there exist increased oxidative stress and oxidative damage induced by chronic bacterial prostatitis in the patients, and such phenomenon was closely related to the course of disease.</p>

Overweight and obesity-induced oxidative stress in children / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate whether overweight and obesity might cause oxidative stress and potential oxidative damage in overweight and obese children, and to explore its possible mechanism.</p><p><b>METHODS</b>Eighty-five overweight and obese children (OOC), and eighty-five age-matched healthy children (HC) were recruited in this case-control study. The present study analyzed spectrophotometrically vitamin C (VC), vitamin E (VE), and 3-carotene (P-CAR) in plasma, as well as the activities of superoxide dismutase (SOD), catalase (CAT), and the level of malondialdehyde (MDA) in erythrocytes.</p><p><b>RESULTS</b>Compared with those of VC, VE, P-CAR, SOD, CAT and MDA in the HC group, the average values of VC, VE, 3-CAR, SOD, and CAT in the OOC group were significantly decreased (P<0.001), while the average value of MDA in the OOC group was significantly increased (P<0.001). The regression analysis demonstrated that VC, VE, P-CAR, SOD, and CAT were negatively correlated (P<0.05-0.01), and MDA was positively correlated with BMI (P<0.05). Fitting to the model of multiple stepwise regression of BMI on VC, VE, P-CAR, SOD, CAT, and MDA in 85 OOC was Y= 27.0041 + 0.2541MDA - 2.1448beta-CAR - 0.0090CAT, where F= 43.8088, P<0.001, r = 0.7866, r(2)= 0.6187, adjusted r(2)= 0.6046. The findings from the reliability analysis for VC, VE, P-CAR, SOD, CAT, and MDA used to reflect increased oxidative stress and potential oxidative damage in the OOC showed that the reliability coefficients (alpha, 6 items) = 0.7231, P<0.0001, and that the standardized item alpha = 0.9207, P<0.0001.</p><p><b>CONCLUSION</b>The present study suggests that there exists an increased oxidative stress in overweight and obese children.</p>

Increased oxidative stress in women with pregnancy-induced hypertension / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate whether pregnancy-induced hypertension (PIH) may increase oxidative stress in women with PIH, and to explore the mechanisms by which PIH may increase oxidative stress and potential free radical damage.</p><p><b>METHODS</b>Seventy women with PIH and seventy women with uncomplicated normotensive pregnancy (UNP) whose age, nutritional conditions, levels of hemoglobin and albumin were all matched, were enrolled in a randomized controlled trial. Their plasma concentrations of nitric oxide (NO), vitamin C (VC), vitamin E (VE), and beta-carotene (beta-CAR) as well as their erythrocyte malondialdehyde (MDA), and activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) were determined by spectrophotometry.</p><p><b>RESULTS</b>Compared with average values of the above experimental parameters in the women with UNP, the average value of erythrocyte MDA in the women with PIH significantly increased (P<0.0001), while the average values of plasma NO, VC, VE, and beta-CAR as well as those of erythrocyte SOD, CAT, and GPX in the women with PIH significantly decreased (P<0.0005-0.0001). The findings from partial correlation analysis (controlling for age) for 70 women with PIH showed that with elevated systolic blood pressure (SBP) and diastolic blood pressure (DBP), MDA value gradually increased (P<0.001), and NO, VC, VE, beta-CAR, SOD, CAT, and GPX values gradually decreased (P<0.02-0.001). The findings from reliability analysis for NO, VC, VE, beta-CAR, SOD, CAT, GPX, and MDA values used to reflect increased oxidative stress and potential free radical damage in women with PIH showed that the reliability coefficients (alpha, 8 items) = 0.7062, P<0.0001, and the standardized item alpha = 0.9116, P<0.0001.</p><p><b>CONCLUSION</b>The findings in the present research suggest that pregnancy-induced hypertension can increase oxidative stress and potential free radical damage in women with pregnancy-induced hypertension.</p>

Oxidative stress and free radical damage in patients with acute dipterex poisoning / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate whether acute dipterex poisoning (ADP) may cause oxidative stress and free radical damage in the bodies of acute dipterex poisoning patients (ADPPs), and to explore the mechanisms by which ADP may cause oxidative stress and free radical damage.</p><p><b>METHODS</b>Fifty ADPPs and fifty healthy adult volunteers (HAVs) whose ages, gender and others were matched with the ADPPs were enrolled in a randomized controlled study, in which concentrations of nitric oxide (NO), vitamin C (VC), vitamin E (VE) and beta-carotene (beta-CAR) in plasma as well as concentration of lipoperoxide (LPO), and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and acetylcholinesterase (AChE) in erythrocytes were determined by spectrophotometric analytical methods.</p><p><b>RESULTS</b>Compared with the average values of experimental parameters in the HAVs group, the average values of plasma NO and erythrocyte LPO in the ADPPs group were significantly increased (P<0.0001), while those of plasma VC, VE and beta-CAR as well as erythrocyte SOD, CAT, GPX and AChE in the ADPPs group were significantly decreased (P<0.0001). Bivariate correlation analysis and partial correlation analysis suggested that when NO and LPO values were increased, and VC, VE, beta-CAR, SOD, CAT and GPX values were decreased in the ADPPs, AChE value was decreased gradually in the ADPPs (P<0.001-0.0001). Reliability analysis of experimental parameters reflecting oxidative stress and free radical damage in the ADPPs showed that the reliability coefficient (8 items) alpha=0.6909, and the standardized item alpha=0.8574.</p><p><b>CONCLUSION</b>The findings in the present study suggest that ADP can cause oxidative stress and free radical damage, and inhibit markedly erythrocyte acetylcholinesterase activity in ADPPs.</p>