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Immigrants lack appropriate health care access and other resources needed to reduce their exposure to preventable environmental health risks. Little is known about the impact of lead exposure and oxidative stress among immigrants. Thus, this study was to examine the differences between the blood lead levels (BLLs) and oxidative stress levels of immigrants and non-immigrants, and to investigate the determinants of increased BLLs or oxidative stress levels among immigrants. We collected demographic data of 239 immigrant women and 189 non-immigrant women who resettled in the central area of Taiwan. Each study participant provided blood samples for genotyping and for measuring blood metal levels and oxidative stress. Recent immigrants were at risk for elevated BLLs. Decreased BLLs, malondialdehyde (MDA), and increased blood selenium levels were significantly associated with duration of residence in Taiwan. Elevated BLLs and MDA in recent immigrants may serve as a warning sign for the health care system. The nation's health will benefit from improved regulation of living environments, thereby improving the health of immigrants.

End stage renal disease patients undergoing long-term dialysis are at risk for abnormal concentrations of certain essential and non-essential trace metals and high oxidative stress. We evaluated the effects of zinc (Zn) supplementation on plasma aluminum (Al) and selenium (Se) concentrations and oxidative stress in chronic dialysis patients. Zn-deficient patients receiving continuous ambulatory peritoneal dialysis or hemodialysis were divided into two groups according to plasma Al concentrations (HA group, Al > 50 g/L; and MA group, Al > 30 to ≤ 50 g/L). All patients received daily oral Zn supplements for two months. Age- and gender-matched healthy individuals did not receive Zn supplement. Clinical variables were assessed before, at one month, and after the supplementation period. Compared with healthy subjects, patients had significantly lower baseline plasma Se concentrations and higher oxidative stress status. After two-month Zn treatment, these patients had higher plasma Zn and Se concentrations, reduced plasma Al concentrations and oxidative stress. Furthermore, increased plasma Zn concentrations were related to the concentrations of Al, Se, oxidative product malondialdehyde (MDA), and antioxidant enzyme superoxide dismutase activities. In conclusion, Zn supplementation ameliorates abnormally high plasma Al concentrations and oxidative stress and improves Se status in long-term dialysis patients.

Objective: Ischemic reperfusion (IR) injury is known to have an important influence on the success of transplant surgery and the occurrence of complications. Malondialdehyde (MDA) is an intermediate metabolite of lipid peroxidation resulting from IR-induced reactive oxygen species. This study was designed to investigate the protective effects of propofol on IR injury in liver transplant recipients., Methods: We analyzed 19 recipients prospectively by measuring the blood levels of MDA at nine predefined intervals; before induction of anesthesia (baseline, T0), 1 hour after surgical incision (T1), 1 minute before reperfusion (T2), 30 seconds after reperfusion (T3), as well as 1, 3, 5, 30, and 60 minutes thereafter (T4-8). These patients were randomly allocated to two groups. The propofol group received an infusion (2 mg/kg per hr) after an induction bolus (2 mg/kg). The control group was prescribed midazolam (0.2 mg/kg) for induction without intravenous anesthetic infusion for maintenance., Results: The highest MDA level occured at T6 in the controls and T7 in the propofol group. Compared with the blood levels at baseline, the MDA levels increased significantly at T2-T8 among controls versus T2, T3, T4, and T7 in the propofol group. Compared to the control group, propofol significantly lowered MDA values at T5-T8., Conclusion: There were significantly higher MDA levels among the control versus the propofol group at 3, 5, 30, and 60 minutes after reperfusion in liver transplant recipients., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objectives: We evaluated the relationship of the plasma copper/zinc (Cu/Zn) ratio with nutritional status, inflammation, oxidative stress, and immune function in peritoneal dialysis patients., Design and Methods: Clinical and laboratory parameters were measured in patients (n=45) and age- and sex-matched healthy individuals (n=30)., Results: There were significant negative correlations of the Cu/Zn ratio with nutrition-related parameters (body mass index [BMI], creatinine, hemoglobin, and albumin) and antioxidant (vitamin C and E) levels and positive correlations of the Cu/Zn ratio with the levels of high sensitivity C-reactive protein (hs-CRP) and oxidation products (malondialdehyde [MDA] and protein carbonyl). The Cu/Zn ratio was negatively correlated with the percentages of B- and T-lymphocyte subsets and the ratio of CD4/CD8 antigens., Conclusions: In peritoneal dialysis patients, elevated Cu/Zn ratios are associated with malnutrition, increased oxidative stress, inflammation, and disrupted immune status., (Copyright © 2010. Published by Elsevier Inc.)

Silica particles and metals are important occupational hazards in foundry workers, and exposure may result in DNA damage and lipid peroxidation through oxidative stress. This study aimed to compare oxidative damage by measuring the levels of plasma malondialdehyde (MDA), urinary 8-hydroxydeoxyguanosine (8-OH-dG) and DNA strand breakage in workers at two foundry plants (exposure group) and in town hall employees (control group) in central Taiwan. Air samples for metals analysis in the workplace were also collected to assess the health risk to foundry workers. Significantly higher MDA levels (4.28 microM versus 1.64 microM), DNA strand breakage (6.63 versus 1.22), and 8-OH-dG levels (5.00 microg/g creatinine versus 1.84 microg/g creatinine) were found in exposure group compared with the control group. Higher levels of these parameters were also found in workers involved in manufacturing than in workers involved in administration. Higher air respirable dust concentrations were found in manufacturing departments (0.99 mg/m(3)) than in administrative departments (0.34 mg/m(3)). The health risk assessment on metals exposure showed that the cancer risk for Cd, Cr and Ni were all above 1 x 10(-6). Future studies are necessary to determine whether metals exposure can contribute to oxidative damage in foundry workers.

The purpose of this study was to evaluate the effects of Baduanjin exercise on oxidative stress, antioxidant status and quality of life in middle-aged women. A quasi-experimental design was adopted. Subjects were 31 middle-aged women. Subjects completed a supervised and standardized Baduanjin exercise program 3 times a week for 12 weeks. Malondialdehyde (MDA) level was measured and determined by using a spectrophotometer for oxidative stress. The superoxide dismutase (SOD) was measured for the antioxidant status. A 36-item Short Form Health Survey (SF-36) was used to evaluate changes in quality of life. All outcome measures were collected before intervention and at the end of a 12-week intervention. The results suggest that there are significant differences in serum SOD level with Baduanjin exercise. SOD level was significantly increased after exercise (p < 0.05). Baduanjin exercise contributed significantly to antioxidant status on these samples. However, a reduction in MDA level was observed. The t-test value was 2.03 with a p-value of 0.052. The changes may be meaningful at a 5% level. There are significant improvements in quality of life after the exercise program. Subjects had greater improvements in 4 dimensions of SF-36, namely physical function, body pain, social function and general mental health (p < 0.05). In conclusion, Baduanjin exercise has beneficial effects on improving quality of life, increasing antioxidant enzymes and reducing oxidative stress in middle-aged women. Reduction of MDA level may be more attributable to the increase in the antioxidant enzyme SOD.

Fly ash and ambient emissions of municipal solid waste incinerators contain polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polycyclic aromatic hydrocarbons (PAHs), other organic compounds, metals, and gases. Hazardous substances such as PCDD/Fs, mercury vapors and other silicates, and the components of bottom ash and fly ash elevate the oxidative damage. We compared oxidative damage in workers exposed to hazardous substances at a bottom ash recovery plant and 3 fly ash treatment plants in Taiwan by measuring their levels of plasma malondialdehyde (MDA) and urine 8-hydroxydeoxyguanosine (8-OH-dG). Significantly higher MDA levels were found in fly ash treatment plant workers (3.20 microM) than in bottom ash plant workers (0.58 microM). There was a significant association between MDA levels in workers and their working environment, especially in the fly ash treatment plants. Levels of 8-OH-dG varied more widely in bottom ash workers than in fly ash workers. The association between occupational exposure and 8-OH-dG levels may be affected by the life style of the workers. Because more dioxins and metals may leach from fly ash than from bottom ash, fly ash treatment plant workers should, as much as possible, avoid exposing themselves to fly ash.

The aim of this study is to examine the relationship between alcohol dependence and oxidative status. The biochemical parameters and antioxidants status were measured among 28 patients with alcohol dependence. Nineteen healthy persons without drinking problem were recruited as the control subjects. The activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyltransferase (gamma-GT), and levels of cholesterol, triglyceride (TG), and uric acid were significantly increased in the specimen of patients compared with control. Serum malondialdehyde (MDA) levels of the patients were found to be significantly increased compared with controls and decreased after abstinence. Superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities were, respectively, 86% and 37% lower in alcoholic patients. After 14 d of abstinence, SOD activity was significantly reduced by 85%, CAT by 52%, and GPX by 54%, whereas no change was found in activity of glutathione reductase (GR). The duration of alcohol dependence is significantly correlated with the levels of MDA. In addition, the activity of CAT was significantly correlated with MDA levels. The results of this study suggest that oxidative stress occurred during alcohol dependence and subsequently affected the antioxidants mechanisms.

The purpose of this study was to compare the levels of interleukin-6 (IL-6) and malondialdehyde (MDA) in healthy controls and diabetic patients without coronary heart disease (CHD). Fasting serum IL-6 and MDA were determined in 30 healthy controls and 52 (20 Type 1 and 32 Type 2) diabetic patients without clinical evidence of CHD. MDA was calculated as oxidative stress. The IL-6 concentration was used to evaluate the cytokine function. Results showed that the serum IL-6 and MDA concentrations are significantly higher in Type 2 diabetic patients (p<0.05). In conclusion, we demonstrated that Type 2 diabetic patients are more influenced by oxidative stress than Type 1 diabetic patients and healthy controls, because of the action of cytokine.

The purpose of this study was to examine whether the symptoms of dysmenorrhea in young women were related to serum malondialdehyde (MDA) and interleukin-6 (IL-6) levels. Ninety-four non-smoking and non-drinking female subjects without serious disease from a nursing college in Taiwan were divided into two groups. Group 1 consisted of 51 subjects without dysmenorrheal, and Group 2 of 43 subjects with dysmenorrheal symptom. All subjects were provided informed consent. Results showed that the serum levels of MDA and of IL-6 were significantly different between the two groups (P < 0.05) and (P < 0.005), respectively. We conclude that the pathological mechanism of dysmenorrhea is mediated by oxidative stress caused by the action of cytokine., (Copyright 2004 Elsevier Inc.)

Total blood glutathione and nonglutathione free sulfhydryl compounds, glutathione peroxidase, and glutathione S-transferase in erythrocytes and plasma and also lipid peroxides in plasma were investigated in 48 male smokers and 42 male nonsmokers. We found that the level of total blood glutathione was significantly increased in young smokers (age <40) but no such change was noted in aging smokers (age>/=40). The activities of glutathione peroxidase and glutathione S-transferase in plasma were significantly decreased in young smokers and the plasma levels of these two enzymes and nonglutathione free sulfhydryl compounds were more drastically decreased in aging smokers. The average concentration of plasma lipid peroxides of the aging smokers (2.76+/-0.46 nmol/ml) was significantly higher than that of the aging nonsmokers (2.32+/-0. 41nmol/ml, P=0.049). On the other hand, the level of total blood glutathione was negatively correlated with the level of plasma lipid peroxides (r=-0.305, P=0.002) and was positively correlated with the smoking index (r=0.307, P=0.019) of all the study subjects under age control. These results indicate that the activities of glutathione peroxidase and glutathione S-transferase declined to a great extent under smoking-mediated oxidative stress in the blood of both young and aging smokers. Moreover, the compensatory generation of total blood glutathione may effectively prevent plasma lipids from peroxidation in young smokers, although the activities of glutathione peroxidase and glutathione S-transferase in plasma were decreased. By contrast, total blood glutathione was inadequate for such protection in the aging smokers. We suggest that supplementation of thiol-group-related agents may be considered for the prevention or alleviation of oxidative stress in aging smokers, whose capability and capacity for the disposal of smoking-mediated free radicals and reactive oxygen species are compromised., (Copyright 1999 Academic Press.)

Objectives: The following hypothesis was tested: plasma manganese concentration is associated positively with the product of lipid peroxidation, and lipid peroxidation is associated negatively with the activities of antioxidants in workers exposed to manganese., Methods: The plasma manganese concentration of 22 manganese-exposed workers and 45 referents was determined by graphite furnace atomic absorption spectrophotometry. Malondialdehyde, the product of lipid peroxidation, was determined by high-performance liquid chromatography, and the activities of protective enzymes were measured by ultraviolet-visible spectrophotometry., Results: The activities of superoxide dismutase, glutathione peroxidase, and catalase spread widely among the referents. The activity of superoxide dismutase and the concentrations of malondialdehyde and manganese were significantly higher in the manganese workers than in the referents. The concentration of malondialdehyde in the exposed workers was correlated strongly with the manganese level of plasma., Conclusions: Malondialdehyde can be used as an index of lipid peroxidation induced by manganese exposure.