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51.
Trace elements as a component of oxidative stress in COPD 总被引:5,自引:0,他引:5
Karadag F Cildag O Altinisik M Kozaci LD Kiter G Altun C 《Respirology (Carlton, Vic.)》2004,9(1):33-37
OBJECTIVE: The purpose of this study was to assess the serum concentrations of those trace elements that act as a component of oxidative stress in COPD patients. Clinically stable COPD outpatients (n = 26) and healthy controls (n = 24) were studied. METHODOLOGY: Serum concentrations of copper (Cu) and zinc (Zn) were determined using a Varian Spectra AA220 flame atomic absorption spectrophotometer. Serum concentration of iron (Fe) was measured by the ferene assay, using a commercially available kit (IL Test Iron) with the ILAb 900 autoanalyser. The lipid peroxidation product malondialdehyde (MDA) in serum samples was measured spectrophotometrically in terms of TBARS (thiobarbituric acid reactive substances). RESULTS: The serum MDA concentration in COPD patients was found to be similar to the control group (0.68 +/- 0.15 nmol/mL vs 0.62 +/- 0.13 nmol/mL, respectively; P= 0.163). The serum concentrations of the trace elements in both study groups were in the normal reference range. There was no difference in Fe concentration between COPD patients and the control group (0.81 +/- 0.38 micro g/mL vs 0.92 +/- 0.41 micro g/mL; P= 0.360). Copper concentrations were higher (1.06 +/- 0.26 microg/mL vs 0.92 +/- 0.19 microg/mL; P <0.040); while zinc was lower in the COPD group compared to the controls (0.83 +/- 0.25 microg/mL vs 1.03 +/- 0.23 microg/mL; P= 0.006). Serum Zn concentrations were lower in the severe COPD patients compared to mild-moderate COPD patients (P = 0.038). CONCLUSION: The results of this study indicate that there are alterations in serum concentrations of trace elements in COPD patients, suggesting that they may play a role in the pathophysiology of this disease by virtue of their role in oxidative stress. We recommend further studies on the role of trace elements in the pathophysiology of COPD, their association with markers of oxidant/antioxidant status and on the clinical significance of their deficiency. 相似文献
52.
MJ Hatfield L Tsurkan JL Hyatt X Yu CC Edwards LD Hicks RM Wadkins PM Potter 《British journal of pharmacology》2010,160(8):1916-1928
Background and purpose:
Carboxylesterases (CEs) metabolize a wide range of xenobiotic substrates including heroin, cocaine, meperidine and the anticancer agent CPT-11. In this study, we have purified to homogeneity human liver and intestinal CEs and compared their ability with hydrolyse heroin, cocaine and CPT-11.Experimental approach:
The hydrolysis of heroin and cocaine by recombinant human CEs was evaluated and the kinetic parameters determined. In addition, microsomal samples prepared from these tissues were subjected to chromatographic separation, and substrate hydrolysis and amounts of different CEs were determined.Key results:
In contrast to previous reports, cocaine was not hydrolysed by the human liver CE, hCE1 (CES1), either as highly active recombinant protein or as CEs isolated from human liver or intestinal extracts. These results correlated well with computer-assisted molecular modelling studies that suggested that hydrolysis of cocaine by hCE1 (CES1), would be unlikely to occur. However, cocaine, heroin and CPT-11 were all substrates for the intestinal CE, hiCE (CES2), as determined using both the recombinant protein and the tissue fractions. Again, these data were in agreement with the modelling results.Conclusions and implications:
These results indicate that the human liver CE is unlikely to play a role in the metabolism of cocaine and that hydrolysis of this substrate by this class of enzymes is via the human intestinal protein hiCE (CES2). In addition, because no enzyme inhibition is observed at high cocaine concentrations, potentially this route of hydrolysis is important in individuals who overdose on this agent. 相似文献53.
1 临床资料软组织挫伤460(男300,女160)例,年龄5~72(平均38)岁,面部伤86例,躯干伤98例,四肢伤200例,躯干合并四肢伤76例,均为12 h内收治病例. 实验组(n=230)给于龙血竭胶囊(龙血竭胶囊是由植物防卫素和龙血竭皂甙组成)口服,3次/d,每次1.2 g;对照组(n=230)给于跌打丸口服,2次/d,每次1丸,疗程均为6 d. 实验组总有效率为96.5%,对照组为83.5%,两组间有显著差别(P<0.01). 实验组用药后3和6 d血糖值均较对照组有明显下降(P<0.01). 实验组与对照组用药后总抗氧化能力(TAO, kU/L)均升高(12.5±0.08→42.5±0.03, 12.6±0.05→32.9±0.04),但实验组升高明显(P<0.01). 相似文献
54.
Sari I Yuksel A Kozaci D Selcuk S Gokce G Yildiz Y Demirel H Sop G Alacacioglu A Gunay N Akkoc N 《Inflammation》2012,35(3):1191-1197
We aimed to evaluate some of the vascular biomarkers in newly diagnosed, colchicine naive familial Mediterranean fever (FMF) patients. Our primary aim was to investigate the effect of regular colchicine treatment on these variables. Twenty-four (12 males [M] and 12 females [F], 33.3?±?13.4?years) newly diagnosed FMF patients were included in the study. These patients were started on colchicine treatment following the initial assessment and were studied again no earlier than 2?months. Five patients were lost to follow-up, and assessment of the on-treatment patients was performed on the remaining 19 patients (8 M and 11 F, 33.6?±?11.8?years). There were 19 healthy subjects (11 M and 8 F, 32.2?±?7.2?years) who served as a control group. Cellular adhesion molecules (CAMs; soluble intercellular adhesion molecule-1 [sICAM-1] and soluble CD146 [sCD146]), plasminogen activator inhibitor-1 (PAI-1), fetuin-A and hs-CRP were studied. Examinations were performed on attack-free periods. The levels of hs-CRP, fetuin-A, sICAM-1, and PAI-1 were significantly higher in newly diagnosed patients compared to those of controls (P?0.05). All studied parameters were significantly downregulated after regular colchicine therapy (P?0.05). Comparison of on-treatment data with controls showed that the levels of the vascular biomarkers, except sCD146, were similar between the groups (P?>?0.05). On-treatment sCD146 was found significantly lower than the controls (P?0.05). In regression analysis, none of the independent variables in the model significantly predicted the vascular biomarkers (P?>?0.05). Administration of therapeutic doses of colchicine markedly reduces vascular injury parameters and normalizes the values in FMF. 相似文献
55.
Nalan Kozaci Mustafa Avcı Ertan Ararat Tansu Pinarbasili Muharrem Ozkaya Ibrahim Etli Eda Donertas Omer F. Karakoyun 《The American journal of emergency medicine》2019,37(5):864-868
Objective
In this study, the accuracy of bedside thoracic ultrasonography (TUSG) performed by emergency physicians with patients in the supine position was compared with that of thoracic computed tomography (TCT) for the determination of thoracic injuries due to trauma.Methods
Patients who suffered the multiple traumas, whose thoracic trauma was identified on physical examination or TCT imaging were included in the study. TUSG was performed following a physical examination by the emergency physician who managed the trauma patient. Subcutaneous emphysema, pneumothorax, pulmonary contusions (PCs), hemothorax, pericardial effusion and tamponade, sternal and clavicular fractures and rib fractures were identified by TUSG. TCT imaging was performed after the ultrasonography examination was completed.Results
Eighty-one patients were included in the study. TCT scans showed subcutaneous emphysema in 16 (19.8%) patients, pneumothorax in 21 (25.9%), PCs in 27 (33.3%), hemothorax in 20 (24.7%), sternum and clavicular fractures in 6 (7.4%) and rib fractures in 21 (25.9%). The sensitivity and specificity of ultrasonography varied for detecting the following pathologies: subcutaneous emphysema (56% and 95%), pneumothorax (86% and 97%), hemothorax (45% and 98%), PCs (63% and 91%), sternal fractures (83% and 97%), clavicular fractures (83% and 100%) and rib fractures (67% and 98%), respectively.Conclusion
In conclusion, ultrasound was found to be highly specific but only moderately sensitive for the identification of thoracic injuries. 相似文献56.
57.
J Mulligan LD Voss ES McCaughey BJ Bailey PR Betts 《Archives of disease in childhood》1998,79(4):318-322
OBJECTIVE: To assess the impact of recent guidelines from the UK joint working party of child health surveillance recommending that all children be measured at age 5 and again between 7 and 9 years of age to determine how many normal school age children are likely to be referred for specialist assessment. METHODS: The longitudinal data of 486 children measured by school nurses in a community setting were examined and compared with measurements made in a research setting by a single, skilled observer. MAIN OUTCOME MEASURES: Number of children identified as having abnormal stature (< 0.4th or > 99.6th centile) and abnormal growth rate height standard deviation score (HSDS) change > 0.67). RESULTS: The community survey identified seven (1.4%) children as having abnormal stature (four short, three tall), 11 (2.3%) were identified as "slow growing", and nine (1.9%) increased their HSDS by more than 0.67. These results were comparable to data collected in ideal research conditions. CONCLUSIONS: Following the recommendations would not result in an excess number of inappropriate referrals. However, this study highlights several unresolved issues such as interobserver variability and time interval between measurements. A large scale prospective study should be considered to establish realistic and cost-effective criteria before implementation of a national screening programme. 相似文献
58.
Lessons Learned From the Implementation of Brighter Bites: A Food Co‐op to Increase Access to Fruits and Vegetables and Nutrition Education Among Low‐Income Children and Their Families 下载免费PDF全文
59.
60.
Carrie P. Earthman PhD RD LD Robert R. Wolfe PhD Steven B. Heymsfield MD 《JPEN. Journal of parenteral and enteral nutrition》2017,41(2):226-237
The 2015 Dudrick Research Symposium “Lean Tissue and Protein in Health and Disease: Key Targets and Assessment Strategies” was held on February 16, 2015, at Clinical Nutrition Week in Long Beach, California. The Dudrick Symposium honors the many pivotal and innovative contributions to the development and advancement of parenteral nutrition made by Dr Stanley J. Dudrick, physician scientist, academic leader, and a founding member of the American Society for Parenteral and Enteral Nutrition. As the 2014 recipient of the Dudrick award, Dr Carrie Earthman chaired the symposium and was the first of 3 speakers, followed by Dr Robert Wolfe and Dr Steven Heymsfield. The symposium addressed the importance of lean tissue to health and response to disease and injury, as well as the many opportunities and challenges in its assessment at the bedside. Lean tissue assessment is beneficial to clinical care in chronic and acute care clinical settings, given the strong relationship between lean tissue and outcomes, including functional status. Currently available bioimpedance techniques, including the use of bioimpedance parameters, for lean tissue and nutrition status assessment were presented. The connection between protein requirements and lean tissue was discussed, highlighting the maintenance of lean tissue as one of the most important primary end points by which protein requirements can be estimated. The various tracer techniques to establish protein requirements were presented, emphasizing the importance of practical considerations in research protocols aimed to establish protein requirements. Ultrasound and other new and emerging technologies that may be used for lean tissue assessment were discussed, and areas for future research were highlighted. 相似文献