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61.
Athanasios C. Pappas Filiz Karadas Peter F. Surai Nicholas A.R. Wood Phillip Cassey Gary R. Bortolotti Brian K. Speake 《Journal of trace elements in medicine and biology》2006,20(3):155-160
Birds deposit the trace element selenium (Se) into their eggs because an adequate supply of this micronutrient is essential for embryonic development. Although there is considerable interest in egg Se with regard to topics as diverse as poultry nutrition and environmental pollution, data on the natural levels of Se in eggs of free-living avian species are currently very limited. To address this lack of information, we measured the yolk Se concentrations in eggs of 14 avian species collected in the wild. The concentrations (ng/g wet yolk) varied from 394 to 2238, with a mean value of 1040. Values (means+/-SD) for eggs from the UK, Canada and New Zealand were, respectively, 522+/-192 (3 species), 1194+/-584 (8 species) and 1147+/-200 (3 species). However, analysis by appropriate statistical models indicates that the effect of phylogenetic relatedness among these species is so significant that it removes any effect of geographical location. In particular, species belonging to the order Passeriformes displayed significantly higher yolk Se levels than Non-Passeriforme species. In marked contrast to the free-living species, our previously published data indicate that the Se concentration in egg yolk of the domestic chicken is only about 100 ng/g wet yolk when the birds are maintained on a basal commercial diet without supplementary Se. The results reveal an extensive interspecies variation in yolk Se (across a 6-fold range) for eggs collected from the wild. Nevertheless, the Se concentrations in the yolks of all the free-living species were far higher (4-21-fold) than that achieved in the yolk of the domestic chicken consuming a standard basal diet. 相似文献
62.
The effects of boron toxicity on root antioxidant systems of two chickpea (Cicer arietinum L.) cultivars 总被引:3,自引:0,他引:3
Murat Ardıc Askım Hediye Sekmen Ismail Turkan Süleyman Tokur Filiz Ozdemir 《Plant and Soil》2009,314(1-2):99-108
Significant differences in the antioxidant systems of the roots of two chickpea (Cicer arietinum L.) cultivars differing in tolerance to drought were observed in under toxic boron (B) conditions. Three-week-old chickpea seedlings were subjected to 0.05 mM (control), 1.6 mM or 6.4 mM B in the form of boric acid (H3BO3) for 7 days. At the end of the treatment period, root length, dry weight, boron concentration, malondialdehyde (MDA) content, and the activities of antioxidant enzymes—superoxide dismutase (SOD), peroxidase (POX), catalase (CAT), ascorbate peroxidase (APOX) and glutathione reductase (GR)—were measured. Root length of the drought-tolerant Gökce cultivar did not change under 1.6 mM B but increased under 6.4 mM B. On the contrary, root length decreased in the drought-sensitive Küsmen cultivar under both B concentrations. While root dry weight was unaffected in Gökce, it decreased in Küsmen under both B concentrations. Boron concentration was significantly higher in Küsmen than in Gökce at both B levels. Significant increases in SOD and POX activities were observed in roots of both cultivars under 1.6 and 6.4 mM B. Root extracts exhibited three SOD and three POX activity bands in both cultivars under B stress when compared to control groups. Although CAT activity in Gökce was increased, it decreased in Küsmen at the highest B concentration as compared to control groups. Roots of both cultivars showed no significant change in APOX activity under B toxicity (except in 1.6 mM B treated roots of Küsmen) when compared to control groups. GR activity in the roots of Küsmen decreased significantly with increasing B concentration. However, a significant increase in GR activity was found in Gökce under 1.6 mM B stress. In addition, lipid peroxidation levels of drought-sensitive Küsmen increased, indicating more damage to membrane lipids due to B toxicity. Lipid peroxidation did not change in the drought-tolerant Gökce cultivar at either B concentration. These results suggest that roots of Gökce are better protected from B-stress-induced oxidative stress due to enhanced SOD, CAT and POX activities under high B levels. 相似文献
63.
Erdem Yavuz Gülay Bayramoğlu B. Filiz Şenkal M. Yakup Arıca 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(14-15):1479-1486
Crosslinked-poly(vinylbenzylchloride), poly(VBC), beads were prepared by suspension polymerization and poly(glycidylmethacrylate) was grafted by surface-initiated-atom radical polymerization (SI-ATRP) technique. Epoxy groups of the grafted poly(GMA) were reacted with hydrazine and ammonia to create an affinity binding sites. The hydrazine and amine functionalized poly(VBC-g-GMA) beads were used as an affinity support for adsorption of invertase from solution and yeast crude extract. The influence of pH, equilibrium time, ionic strength and initial invertase concentration on the adsorption capacities of both hydrazine and amine functionalized beads has been investigated. Maximum invertase adsorptions onto hydrazine and amine functionalized beads, were 86.7 and 30.4 mg/g at pH 4.0 and 5.5, respectively. The experimental equilibrium data fitted well to the Temkin isotherm model. Finally, the hydrazine functionalized poly(VBC-g-GMA) beads were used for the purification of invertase from crude yeast extract in a batch system and the purity of the eluted invertase from the hydrazine functionalized beads was determined as 92% by HPLC from single step purification protocol. 相似文献
64.
Caffeic acid phenethyl ester improves oxidative organ damage in rat model of thermal trauma 总被引:1,自引:0,他引:1
Gurel A Armutcu F Hosnuter M Unalacak M Kargi E Altinyazar C 《Physiological research / Academia Scientiarum Bohemoslovaca》2004,53(6):675-682
Severe burn injuries cause functional impairment in distant internal organs. Although this mechanism is not clear, it is possible that free radical toxicity plays an important role. Research in animals and clinical studies have shown that there is a close relationship between a lipid peroxidative reaction and secondary pathological changes following thermal injury. It has been demonstrated that antioxidant treatment prevents oxidative tissue damage associated with thermal trauma. This study was designed to determine the possible protective effect of caffeic acid phenethyl ester (CAPE) treatment against oxidative damage in the kidney and lung induced by thermal injury. Rats were decapitated either 1, 3 or 7 days after burn injury. CAPE was administered intraperitoneally immediately after thermal injury. Kidney and lung tissues were taken for the determination of malondialdehyde (MDA) level, myeloperoxidase (MPO), catalase (CAT), superoxide dismutase (SOD) and xanthine oxidase (XO) activities. Severe skin thermal injury caused a significant decrease in SOD and CAT activities, as well as significant increases in MDA level, XO and MPO activities in tissues during the postburn period. Treatment of rats with CAPE (10 micromol/kg) significantly elevated the decreased SOD and CAT activities, while it decreased MDA levels and MPO as well as XO activity. 相似文献
65.
Since overexcitation of excitatory amino acid is an important mechanism in seizure genesis wherein free radicals have recently been suggested to play a critical role, we explored the effects of caffeic acid phenethyl ester (CAPE) administration in pentylenetetrazole (PTZ)-induced seizure in mice. CAPE prevents the oxidative damage in brain tissue induced by PTZ, scavenging reactive oxygen species (ROS). Our results demonstrate that CAPE treatment which prevents free radical production and ameliorates seizure severity may be useful at least as an adjunctive treatment of seizure disorders. 相似文献
66.
67.
Effectiveness of algae in the treatment of a wood-based pulp and paper industry wastewater 总被引:4,自引:0,他引:4
In this study, the ability of algae to treat a wood-based pulp and paper industry wastewater was investigated. Tests were performed in batch reactors seeded with a mixed culture of algae. Under different lighting and initial wastewater strength conditions, changes in COD, AOX and color contents of reactors were followed with time. Algae were found to remove up to 58% of COD, 84% of color and 80% of AOX from pulp and paper industry wastewaters. No remarkable differences were observed in COD and color when light intensity and wastewater strength were changed, while AOX removals were strongly affected. Algal species identification studies revealed that some green algae (Chlorella) and diatom species were dominant in the treatment. The study also showed that algae grew mixotrophically, while the main mechanism of color and organics removal from pulping effluents was partly metabolism and partly metabolic conversion of colored and chlorinated molecules to non-colored and non-chlorinated molecules. Adsorption onto algal biomass was not so effective. 相似文献
68.
Abdurrahim Kocyigit Ozcan Erel Mehmet S. Gurel Senel Avci Necmeddim Aktepe 《Biological trace element research》1998,65(3):271-281
The aim of this study was to measure the alterations in serum selenium (Se), copper (Cu), zinc (Zn), and iron (Fe) concentrations
and their carrier proteins, ceruloplasmin (Cp), transferrin (Tf) albumin, and related antioxidant enzyme activities, erythrocyte
Cu-Zn Superoxide dismutase (Cu-Zn SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities in patients with cutaneous
leishmaniasis (CL). Erythrocyte Cu-Zn SOD activities, serum Cu concentrations, and Cp levels were found to be significantly
higher in the patients group than those of controls. However, GSH-Px and CAT activities and Se, Zn, Fe, and Tf levels were
lower in patients than in the control subjects. There were positive important correlation’s between Cu-Zn SOD and Cp, Cu-Zn
SOD and Cu, Cp and Cu, GSH-Px and Se, and Fe and CAT in the patients group. Our results showed that serum essential trace
elements Se, Zn, Cu, and Fe concentrations and their related enzymes Cu-Zn SOD, GSH-Px, and CAT activities change in CL patients.
The changes may be a part of defense strategies of organism and are induced by the hormonelike substances. 相似文献
69.
Istemihan Tengiz Ertugrul Ercan Fahri Sahin Emin Alioglu Can Duman Guray Saydam Filiz Buyukkececi 《Trials》2005,6(1):1-5
Background
In high-risk coronary artery bypass patients; off-pump versus on-pump surgical strategies still remain a matter of debate, regarding which method results in a lower incidence of perioperative mortality and morbidity. We describe our experience in the treatment of high-risk coronary artery patients and compare patients assigned to on-pump and off-pump surgery.Methods
From March 2002 to July 2004, 86 patients with EuroSCOREs > 5 underwent myocardial revascularization with or without cardiopulmonary bypass. Patients were assigned to off-pump surgery (40) or on-pump surgery (46) based on coronary anatomy coupled with the likelihood of achieving complete revascularization.Results
Those patients undergoing off-pump surgery had significantly poorer left ventricular function than those undergoing on-pump surgery (28.6 ± 5.8% vs. 40.5 ± 7.4%, respectively, p < 0.05) and also had higher Euroscore values (7.26 ± 1.4 vs. 12.1 ± 1.8, respectively, p < 0.05). Differences between the two groups were nonsignificant with regard to number of grafts per patient, mean duration of surgery, anesthesia and operating room time, length of stay intensive care unit (ICU) and rate of postoperative atrial fibrillationConclusion
Utilization of off-pump coronary artery bypass graft (CABG) does not confer significant clinical advantages in all high-risk patients. This review suggest that off-pump coronary revascularization may represent an alternative approach for treatment of patients with Euroscore ≥ 10 and left ventricular function ≤ 30%. 相似文献70.
OBJECTIVE: To assess the diagnostic value of fine needle aspiration cytology (FNAC) in ovarian lesions. STUDY DESIGN: Sixty-two fine needle aspirations of varied ovarian masses were performed between January 2000 and February 2003. Aspiration material was obtained from fresh tissues at the time of frozen section before dissection of the specimens. The slides were evaluated by a pathologist who was blinded to the gross findings and histopathologic diagnosis. RESULTS: A total of 62.9% of cases were assessed as malignant and 30.6% as benign. Two false positive and 2 false negative cases occurred. In our series the overall sensitivity and specificity were 95.1% and 90.4%, respectively. Seven benign and 15 malignant lesions could be subclassified specifically. CONCLUSION: We studied excised specimens, but since ovarian masses are reachable by laparoscopically and ultrasonographically guided aspiration, FNAC can be used for diagnoses of these lesions. If a multidisciplinary approach can be carried out in patients with ovarian lesions, cytopathologic interpretation can provide optimum benefits. 相似文献