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61.
Cytokinemia and oxidative stress are important factors responsible for an inadequate immune response in the early course of acute pancreatitis (AP). The aim of the study was to evaluate the profiles of interleukin 18 (IL-18), glutathione peroxidase (GPx), and selenium concentrations in serum with respect to AP severity and to study the relationships between these parameters and recognized prognostic indicators of AP severity. Prospective clinical analyses were performed on 61 patients with mild and severe forms of AP and for 15 healthy volunteers. In both forms of AP severity, the IL-18 concentration in the serum was significantly higher than in healthy controls. In the severe form of AP, the IL-18 concentration was the highest and exceeded significantly the values recorded on the 1st, 2nd, 3rd, 5th, and 10th days of mild AP. A significantly lower GPx concentration in the serum was recorded in severe AP compared to the mild form and in the control group. There was a significantly lower selenium concentration in the severe form of AP. Significant correlations between GPx and selenium, between IL-18 and GPx, and between IL-18 and selenium were recorded. The ROC analysis shows a high prognostic accuracy of IL-18 and GPx concentrations in the determination of AP severity. IL-18 is released early in the course of AP and may be a key immunomodulator of the inflammatory response in the severe form of this disease. Low GPx and selenium concentrations in severe AP reflect the lower antioxidative ability in this form of AP. IL-18 and GPx may represent new indicators of AP severity.  相似文献   
62.
目的探讨硒对4-羟基壬烯酸(HNE)和β淀粉样蛋白(Aβ)诱导的神经细胞凋亡率的影响及其作用机制。方法取原代大鼠胚胎海马神经细胞置常规培养液中培养后为未处理1组和未处理2组;细胞置于0、100和200nmol/L亚硒酸钠中,加HNE处理24h,分别为对照1组、亚硒酸钠A、B组;细胞置于0、200、500和1000nmol/L亚硒酸钠中,加入Aβ处理24h,分别为对照2组、亚硒酸钠C、D和E组;将SH-SY5Y置于培养液中培养为空白组;细胞置于0、50、100和200nmol/L亚硒酸钠中,加入HNE处理24h,分别为对照3组、亚硒酸钠A1、B1和C1组。采用锥虫蓝染色和细胞形态学检测细胞凋亡率,采用荧光染料H2DCF-DA检测细胞活性氧水平。结果与未处理1组和未处理2组比较,对照1组、对照2组细胞凋亡率明显增加;与对照1组和对照2组比较,亚硒酸钠A、B、C、D和E组细胞凋亡率明显降低(P<0.05,P<0.01)。与空白组比较,对照3组细胞活性氧水平明显升高;与对照3组比较,亚硒酸钠A1、B1和C1组活性氧水平明显降低(P<0.01)。结论硒能够通过抗氧化应激作用抑制HNE和Aβ诱导的神经细胞凋亡。  相似文献   
63.
This study was performed to determine the hepatotoxicity of di(2‐ethylhexyl)phthalate (DEHP) in relation to selenium status. In 3‐week‐old Sprague‐Dawley rats, selenium deficiency was induced by a ≤0.05 selenium mg/kg. A selenium supplementation group was given 1 mg selenium/kg diet for 5 weeks. Di(2‐ethylhexyl)phthalate‐treated groups received 1000 mg/kg dose by gavage during the last 10 days of the experiment. Histopathology, peroxisome proliferation, catalase (CAT) immunoreactivity and activity and apoptosis were assessed. Activities of antioxidant selenoenzymes [glutathione peroxidase 1 (GPx1), glutathione peroxidase 4 (GPx4), thioredoxin reductase (TrxR1)], superoxide dismutase (SOD), and glutathione S‐transferase (GST); aminotransferase, total glutathione (tGSH), and lipid peroxidation (LP) levels were measured. Di(2‐ethylhexyl)phthalate caused cellular disorganization while necrosis and inflammatory cell infiltration were observed in Se‐deficient DEHP group (DEHP/SeD). Catalase activity and immunoreactivity were increased in all DEHP‐treated groups. Glutathione peroxidase 1 and GPx4 activities decreased significantly in DEHP and DEHP/SeD groups, while GST activities decreased in all DEHP‐exposed groups. Thioredoxin reductase activity increased in DEHP and DEHP/SeS, while total SOD activities increased in all DEHP‐treated groups. Lipid peroxidation levels increased significantly in SeD (26%), DEHP (38%) and DEHP/SeD (71%) groups. Selenium supplementation partially ameliorated DEHP‐induced hepatotoxicity; while in DEHP/SeD group, drastic changes in hepatic histopathology and oxidative stress parameters were observed.  相似文献   
64.
65.
Background: Oxidative stress is believed to play a crucial role in aging and age‐related diseases, and is widely thought to increase morbidity and mortality in the elderly. Assessment of biomarkers of oxidative stress, such as 8‐isoprostane and 8‐hydroxy‐2‐deoxyguanosine, are considered to be useful in predicting disease risks at the population level. Objective: The aim of the present study was to assess the health status of the elderly by comparing their lifestyles and levels of oxidative stress biomarkers. Methods: We carried out a cross‐sectional study where urine samples from a total of 100 elderly men and women were assayed for 8‐isoprostane, 8‐hydroxy‐2‐deoxyguanosine, selenium, cadmium and creatinine. They were asked to answer a questionnaire that included questions about their lifestyle. Results: Most of the participants were prehypertensive, non‐alcohol users and on a rich plant‐based diet. There were no differences in any biomarkers of oxidative stress between men and women. 8‐Isoprostane was found to correlate positively with systolic blood pressure in women, but not in men. There was a slight increase of 8‐isoprostane in participants with a poor intake of vegetables, and a decrease of 8‐hydroxy‐2‐deoxyguanosine in participants who consumed fish. Multiple regression analysis showed that oxidative stress biomarkers were positively associated with cadmium, and negatively associated with selenium and fish intake in all participants, 89% of which were non‐smokers. Conclusion: Results from the present study show that fish intake has the potential of decreasing oxidative stress among elderly persons. Geriatr Gerontol Int 2012; 12: 547–554.  相似文献   
66.
目的 探讨乳腺X线摄影非晶硒探测器点状脱膜伪影及其空间分布特点与X线曝光参数(kV,mAs)之间的关系,并提出相应的应对措施.方法 用不同厚度乳腺体模在不同的X线曝光参数(kV,mAs)下成像,通过系统坏点检测程序计算点状脱模伪影数量与成像参数的关系并观察其空间分布特点.选择恰当的校准参数对非晶硒探测器进行校准后通过体模成像和临床实践,观察校准后点状伪影的变化.结果 不同厚度乳腺体模在不同的曝光参数成像时,点状脱膜伪影的空间分布特点和数量不同.恰当校准后,体模成像和临床实践显示,点状脱模伪影明显减少.结论 为了提高乳腺X线成像质量,需根据点状脱膜伪影与曝光参数的关系选择恰当的校准参数.  相似文献   
67.
68.

Background

The present study aimed to identify independent correlates of toenail selenium levels and to examine the association between toenail selenium levels and metabolic syndrome in Korean adults.

Methods

Cross‐sectional analysis was conducted using baseline data from the Trace Element Study of Korean Adults in the Yeungnam area, an ongoing cohort study of Korean adults over the age of 35 years. The baseline survey consisted of questionnaires on demographics, lifestyle characteristics and medical information. Dietary information was obtained through a validated semi‐quantitative food frequency questionnaire. Toenail selenium levels were quantified using neutron activation analysis. Biomarkers associated with metabolic syndrome were obtained from biennial medical check‐ups.

Results

In the multivariable‐adjusted analyses, independent lifestyle and dietary correlates of higher selenium levels were alcohol drinking (4.62% higher than nondrinking) and egg intake (0.43% higher per weekly serving), whereas current smoking (5.42% lower than nonsmoking) and vegetable consumption (0.05% lower per weekly serving) were associated with lower toenail selenium levels. In the multivariable adjusted logistic regression, no significant association was observed between toenail selenium levels and metabolic syndrome (odds ratio = 1.33, 95% confidence interval = 0.58–3.05).

Conclusions

Multiple lifestyle and dietary factors influenced toenail selenium levels, although no meaningful association was observed between toenail selenium levels and metabolic syndrome in Korean adults. Future prospective large‐scale cohort studies are required to determine whether there is a causal relationship between selenium levels and metabolic syndrome in Korean adults.
  相似文献   
69.
黄慧 《西部医学》2022,34(10):1405-1408
硒是机体生长发育及代谢所必需的元素,孕期硒营养不良可能会对妊娠结局产生不良影响,因此孕妇保持适宜的硒营养状态是非常重要的。但目前针对孕妇硒营养状态的评估方法及孕期是否需要常规补硒尚未达成共识,尚需更多更深入的研究提供依据。本文就孕期硒营养状况对母婴结局的影响作一述评,旨在为临床提供一定的参考。  相似文献   
70.
This study was designed to investigate the possibility of β‐cyfluthrin to induce oxidative stress and biochemical perturbations in rat liver and the role of selenium in alleviating its toxic effects. Male Wister rats were randomly divided into four groups of seven each, group I served as control, group II treated with selenium (200 µg/kg BW), group III received β‐cyfluthrin (15 mg/kg BW, 1/25 LD50), and group IV treated with β‐cyfluthrin plus selenium. Rats were orally administered their respective doses daily for 30 days. The administration of β‐cyfluthrin caused elevation in lipid peroxidation (LPO) and reduction in the activities of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), glutathione S‐transferase (GST), glutathione peroxidase (GPx), and glutathione reductase (GR). A decrease in reduced glutathione (GSH) content was also observed. Liver aminotransferases (AST and ALT) and alkaline phosphatase (ALP) were decreased, whereas lactate dehydrogenase (LDH) was increased. Selenium in β‐cyfluthrin‐induced liver oxidative injury of the rats modulated LPO, CAT, SOD, GSH, GST, GPx, and GR. Also, liver AST, ALT, ALP, and LDH were maintained near normal level due to selenium treatment. It is concluded that selenium scavenges reactive oxygen species and render a protective effect against β‐cyfluthrin toxicity. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1323–1329, 2014.  相似文献   
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