Decreased serum ceruloplasmin concentration in aluminum welders exposed to ozone

Summary During an epidemiological survey on arc welders, serum copper and ceruloplasmin were determined in two groups of workers. One group consisted of aluminum welders who were divided into two groups: 13 welders working inside aluminum tanks (confined atmosphere) and 8 welders engaged in the production of vans for dump trucks (nonconfined atmosphere). The reference group consisted of 26 workers of the same plant who were not exposed to welding fumes. Ozone, the major pollutant in aluminum arc welding, was thought to be the principal factor in the significant decrease (P < 0.01) of mean ceruloplasmin in confined welders. This decrease in the level of ceruloplasmin was still within the reference values and was not linked to age or to tobacco consumption. We found a linear relationship between ceruloplasmin concentration and the cumulated worktime along the week. This effect could be a sign in the serum of a lung reaction against oxidant activity in this type occupational exposure.     

Neuromelanin-containing neurons of the substantia nigra accumulate iron and aluminum in Parkinson's disease: a LAMMA study

The Laser Microprobe Mass Analyzer (LAMMA) is a sensitive instrument for identifying and localizing trace elements in tissue samples. Using LAMMA, we have examined melanin-containing neurons of the substantia nigra in patients with Parkinson's disease (PD) and controls. We found that iron significantly accumulates within neuromelanin granules of patients with PD compared to controls. Increased aluminum was found in the neuromelanin granules of 2 of 3 PD cases but in no controls. The accumulation of iron and aluminum, which are known to promote oxidant stress, may account for the selective degeneration of neuromelanin-containing neurons in PD.     

氧化修饰低密度脂蛋白在子痫前期中的测定及意义

目的测定氧化修饰低密度脂蛋白(oxLDL)在子痫前期中的变化,探讨其意义。方法采用酶联免疫吸附法(ELISA)测定子痫前期重度组、子痫前期轻度组及对照组血清oxLDL水平。结果(1)3组孕妇血清oxLDL比较,见子痫前期重度组升高(49.35±4.22)μg/d l,与对照组(31.71±3.51)μg/d l比较有显著差异(P<0.01);子痫前期轻度组(39.12±2.37)μg/d l升高,与对照组比较有显著差异(P<0.05);子痫前期重度组与轻度组比较无显著差异(P>0.05)。(2)子痫前期重度组血清oxLDL与收缩压、舒张压呈正相关(r=0.51,P<0.01;r=0.47,P<0.05)。结论研究提示oxLDL可能是子痫前期发病的重要因素。     

紫外分光光度法测定呋麻滴鼻液中盐酸麻黄碱的含量

目的建立呋麻滴鼻液中盐酸麻黄碱的紫外分光光度法的含量测定方法。方法次氯酸钠为氧化剂，测定由盐酸麻黄碱被次氯酸钠氧化后的氧化产物苯甲醛，检测波长为249nm。结果盐酸麻黄碱在2～18μg/ml范围内，线性关系良好(r=0．9996)，平均回收率为98．05％(n=9，RSD=0．72％)。结论本法灵敏度高，快捷准确。     

Association between serum uric acid levels and cardiovascular events in hospitalized patients with type 2 diabetes

AimsThis study aimed to determine the association between serum uric acid (UA) levels and cardiovascular events in hospitalized patients with type 2 diabetes mellitus (T2DM).MethodsA retrospective cohort study was conducted in 2227 hospitalized patients with T2DM. Cox proportional hazards regression was used to assess the association between serum UA and cardiovascular events, including cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, heart failure, unstable angina, and arrhythmias requiring hospitalization.ResultsAmong 1314 men, 143 (10.9%) experienced cardiovascular events. Serum UA level was not associated with the risk of cardiovascular events (hazard ratio [HR] per 100 μmol/L increase in serum UA: 1.12, 95% confidence interval [CI]: 0.90–1.40). Among 913 women, 96 (10.5%) experienced cardiovascular events. For every 100 μmol/L increase in serum UA level, the risk of experiencing a cardiovascular event increased by 27% (HR: 1.27, 95% CI: 1.02–1.57).ConclusionsIn hospitalized patients with T2DM, baseline serum UA levels were positively associated with cardiovascular events in women, but not in men. Serum UA levels may be a significant independent risk factor for cardiovascular events in women with T2DM.     

葛根素对难治性心力衰竭患者氧化/抗氧化系统失衡的调节作用

目的：探讨葛根素对难治性心力衰竭患者血中氧化/抗氧化指标的调节作用。方法：选取健康成人34例，检测静脉血全血超氧 化物歧化酶(SOD)、全血谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)的活性及血浆脂质过氧化物(LPO)和丙二醛(MDA)的 浓度，然后与难治性心力衰竭组治疗前的此5项指标进行比较；选择76例难治性心力衰竭患者，随机分成两组，试验前均监测静脉血 全血 SOD、GSH-Px 和 CAT 的活性及血浆 LPO 和 MDA 的浓度并评价心功能，然后试验组在给予常规治疗的同时合并给予葛根素 注射液300 mg/d，稀释后静脉滴注，疗程2周；对照组只给予常规治疗，2周后，复测上述指标，比较各组治疗前后的变化。结果：1) 难 治性心力衰竭患者全血 SOD、全血 GSH-Px 和 CAT 的活性比健康对照组低，而血浆 LPO 及 MDA 的浓度比健康对照组高，均 P＜0． 01；2) 葛根素组试验前后比较，全血 SOD、全血 GSH-Px 和 CAT 活性明显增高，且血浆 LPO 和全血 MDA 浓度明显降低，均P＜0． 05；而对照组则无显著变化，P＞0． 05；3) 葛根素组心力衰竭纠正的有效率显著高于对照组，P＞0． 05。结论：难治性心力衰竭患者机 体的抗氧化防御能力降低，葛根素可通过提高机体的抗氧化能力，消除氧自由基和脂质过氧化物，起到纠正心力衰竭的作用。     

Mitochondrial glutathione depletion in alcoholic liver disease

Alcoholic liver disease (ALD) is one the most serious consequences of chronic alcohol abuse. Liver cirrhosis, the culmination of the illness, is one of the leading causes of death in Western countries. Mitochondria are a target of ethanol intoxication mainly due to the toxic effects of acetaldehyde, a byproduct of ethanol metabolism. Morphological and functional changes in mitochondria are one of the key hallmarks of chronic ethanol exposure in both chronic alcoholics and experimental models of alcoholism. The functional changes observed in mitochondria from ethanol-treated animals are translated in an overall decrease in ATP levels resulting from a lower rate of ATP synthesis as a consequence of impaired processing at the translational level of some components of oxidative phosphorylation encoded by mitochondrial DNA genome. Mitochondrial glutathione (GSH) plays a critical role in the maintenance of cell functions and viability and in mitochondrial physiology by metabolism of oxygen free radicals generated in the respiratory chain. GSH in mitochondria originates from cytosol by a transport system which translocates GSH into the matrix. This transport system is impaired in chronic ethanol-fed rats, which translates in a selective and significant depletion of the mitochondrial GSH content resulting in the development of an increased susceptibility to oxidant stress. Using the intragastric infusion model of experimental ALD in rats, the profound and selective mitochondrial GSH depletion precedes the onset of alcoholic liver disease, mitochondrial lipid peroxidation, and progression of liver damage. These results suggest that depletion of mitochondrial GSH by impairment of its transport from cytosol into mitochondria could be an additional contributing factor in the development of ALD by favoring pro-oxidant production and oxidant stress in mitochondria.     

Oxidant Stress in Hemodialysis Patients: What Are the Determining Factors?

Oxidant stress contributes to morbidity in hemodialysis patients. Three possible causes of oxidant stress have been suggested: the uremic state, the dialyzer membrane, and bacterial contaminants from the dialysate. Oxidant stress occurs in uremia before dialysis therapy is initiated, as evidenced by increased production of reactive oxygen species, increased levels of oxidized plasma proteins and lipids, and decreased antioxidant defenses. It has been proposed that increased production of reactive oxygen species during hemodialysis is also an important contributor to oxidant stress. Hemodialysis is associated with a transient increase in production of reactive oxygen species, particularly with cellulose membranes. In addition, surveys have shown widespread contamination of dialysate by endotoxin, which may cross membranes and prime production of reactive oxygen species by phagocytic cells. Recent studies, however, show a decrease in protein oxidation from pre- to post-dialysis and a normalization of neutrophil reactive oxygen species production. Taken together, these data suggest that uremia, per se, is the most important cause of oxidant stress in hemodialysis patients. Dialysate quality may also contribute to oxidant stress, but evidence that the dialyzer membrane plays a role is weak.     

抗氧化营养素与老年性黄斑变性的防治

老年性黄斑变性(Age-related macular degeneration,AMD)是老年人视力损伤和致盲的主要原因。视网膜的高耗氧性,高长链多不饱和脂肪酸含量,作为氧自由基的靶点和暴露于可见光的特性使其易产生氧化应激。大量研究均显示抗氧化营养素有助于老年性黄斑变性的防治,本文就其最新研究进展进行综述。眼科学报2007;23:193-198.