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81.
Belma Giray Josiane Arnaud İskender Sayek Alain Favier Filiz Hıncal 《Journal of trace elements in medicine and biology》2010,24(2):106-110
Importance of iodine and selenium in thyroid metabolism is well known, but the roles of other essential trace elements including copper, zinc, manganese and iron on thyroid hormone homeostasis remain unclear. The aim of this study was to investigate the status of those trace elements in benign thyroid diseases and evaluate possible links between trace element concentrations and thyroid hormones.The study group was composed of 25 patients with multinodular goiter. Concentrations of thyroid hormones (plasma-free thyroxine, FT4; free triiodothyronine, FT3; and thyrotropin, TSH), selenium, copper, zinc, manganese and iron in plasma, and urinary iodine were determined. The results were compared with those of a healthy control group (n=20) with no thyroid disorder.A mild iodine deficiency was observed in the patients with multinodular goiter whereas urinary iodine levels were in the range of “normal” values in healthy controls. All patients were euthyroid, and their thyroid hormone concentrations were not significantly different from the control group. Plasma selenium, zinc and iron concentrations did not differ from controls, while copper and manganese levels were found to be significantly higher in the patients with multinodular goiter indicating links between these trace elements and thyroid function and possibly in development of goiter. Besides iodine, there was a significant correlation between plasma copper concentration and FT3/FT4 ratio. 相似文献
82.
One of the main interesting areas where it is possible to work is in the applied sciences. This includes, in a wide perspective,
also the work done as a mixture of knowledge transfer and further development of research in a very pragmatic basis. As an
example of this kind of work you can read here some basic information about the method ECOPROFIT, successfully applied in
several countries in Europe and Asia. ECOPROFIT bases in the framework of Public–Private-Partnership (PPP) projects and it
is dedicated to reach a sustainable awareness on climate protection, both at municipal administrations and at private companies.
The method ECOPROFIT aims both economic and environmental aspects and also doesn’t ignore the added social value of the developed
climate protection measures. This enables ECOPROFIT to comply with the three dimensions of sustainable development. 相似文献
83.
84.
Muharrem Bitiren Ali Ziya Karakilcik Mustafa Zerin Ilyas Ozardalı Sehabettin Selek Yaşar Nazlıgül Abdullah Ozgonul Davut Musa Ali Uzunkoy 《Biological trace element research》2010,136(1):87-95
Ulcerative colitis increases oxidative damage accompanied by production of free oxygen radicals. Selenium (Se) and vitamin
E are two natural antioxidants. The present study was undertaken to investigate the possible protective role of Se and vitamin
E combination in experimental colitis induced by acetic acid (AA) in rats. This study was carried out on three groups, namely
the first (control), the second (experimental colitis group, 2 ml 5% acetic acid), and the third groups (2 ml 5% acetic acid,
vitamin E (100 mg/kg body weight (bw)) plus Se (0.2 mg/kg bw)). The activities of catalase (CAT), prolidase (PRS), myeloperoxidase
(MPO), total antioxidant capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI), total thiol (T-SH) were
determined in plasma and colon samples. Macroscopic and microscopic damages in colon were increased by AA treatment (p < 0.01 and p < 0.01, respectively), whereas they were decreased by selenium and vitamin E treatment (p < 0.05 and p < 0.01, respectively). The activities of CAT and PRS in the plasma and colon were significantly affected (p < 0.05 and p < 0.01) by treatment of AA, Se, and vitamin E. MPO activity in colon was increased (p < 0.01) by AA treatment and decreased (p < 0.05) by Se and vitamin E administration. The values of TOS and OSI in plasma were increased (p < 0.5) by AA. The TAC and T-SH in colon were decreased (p < 0.05) by AA and increased (p < 0.05) by Se and vitamin E. Based upon these results, Se and vitamin E may play an important role in preventive indication
of the oxidative damage associated by acetic acid caused inflammation. 相似文献
85.
Canan Küçükgergin A. Fatih Aydın Gül Özdemirler-Erata Güldal Mehmetçik Necla Koçak-Toker Müjdat Uysal 《Biological trace element research》2010,135(1-3):264-274
Hypercholesterolemia and lipid peroxidation play complementary roles in atherosclerosis. Artichoke (Cynara scolymus L., Asteraceae) leaf extract (ALE), rich in antioxidants, has cholesterol-reducing effect. We investigated the effect of ALE on serum and hepatic lipid levels and pro-oxidant–antioxidant balance in the liver and heart of hypercholesterolemic rats. Rats were fed on 4% (w/w) cholesterol and 1% cholic acid (w/w) supplemented diet for 1 month. ALE (1.5 g/kg/day) was given by gavage during the last 2 weeks. High cholesterol (HC) diet caused significant increases in serum and liver cholesterol and triglyceride levels. It increased malondialdehyde (MDA) and diene conjugate (DC) levels in both tissues. Hepatic vitamin E levels and hepatic and cardiac glutathione peroxidase (GSH-Px) activities decreased, but superoxide dismutase and glutathione transferase activities, glutathione, and vitamin C levels remained unchanged due to HC diet. Serum cholesterol and triglyceride levels and ratio of cholesterol to high-density lipoprotein (HDL)-cholesterol decreased in ALE plus HC-treated rats, but liver cholesterol and triglyceride levels remained unchanged. Significant decreases in hepatic and cardiac MDA and DC levels and increases in hepatic vitamin E and GSH-Px activities were observed in ALE-treated hypercholesterolemic rats. Our results indicate that ALE decreases serum lipids and hypercholesterolemia-induced pro-oxidant state in both tissues. 相似文献
86.
87.
Bülent Yılmaz Musa H Asyalı Eren Arıkan Sinan Yetkin Fuat Özgen 《Biomedical engineering online》2010,9(1):39
Background
Polysomnography (PSG) is used to define physiological sleep and different physiological sleep stages, to assess sleep quality and diagnose many types of sleep disorders such as obstructive sleep apnea. However, PSG requires not only the connection of various sensors and electrodes to the subject but also spending the night in a bed that is different from the subject's own bed. This study is designed to investigate the feasibility of automatic classification of sleep stages and obstructive apneaic epochs using only the features derived from a single-lead electrocardiography (ECG) signal. 相似文献88.
Fahriye Ceyda Dudak Esra Acar Soykut Murat Erman Oğuz Fatih Yaşar İsmail Hakkı Boyacı 《Journal of molecular recognition : JMR》2010,23(4):369-378
Staphylococcal enterotoxin B (SEB) is an exotoxin produced by Staphylococcus aureus and commonly associated with food poisoning. In this study, SEB‐binding peptides were identified by screening a phage displayed peptide library. The binding of peptides to SEB was tested with isothermal titration calorimetry (ITC) and of the five selected peptides, three showed affinity to SEB, with one measured to have the highest affinity constant (105 M?1). ITC revealed that the interaction of peptide ligands with SEB was driven entropically and the binding was dominated by hydrophobic interactions. Circular dichroism (CD) measurements and molecular dynamics (MD) simulations, together, give a structural insight into the interaction of peptides with SEB. While SEB binding peptides showed random coil structure before binding, after complex formation they had more ordered structures. The peptide with highest affinity to SEB showed stable conformation during MD simulation. Taken together, our approach about thermodynamic and structural characterization of peptide ligands can be used to develop aptamers, with high affinity and selectivity, for biosensor applications. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
89.
Effects of Selenium Supplementation on Antioxidant Defense and Glucose Homeostasis in Experimental Diabetes Mellitus 总被引:1,自引:0,他引:1
Erbayraktar Z Yilmaz O Artmann AT Cehreli R Coker C 《Biological trace element research》2007,118(3):217-226
The objective of this study was to investigate the effects of different forms of Se supplementation on the antioxidant defense
and glucose homeostasis in experimental diabetes. Sodium selenate (SS) or selenomethionine (SM) were administered (2 μmol
Se kg−1 day−1) via orogastric route to streptozotocine (STZ)-induced diabetic rats in addition to basal diet for 12 weeks. Glucose levels
in whole blood, glutathione peroxidase (GSH-Px) activity in erythrocytes, Se and fructosamine levels in plasma were evaluated
monthly. Plasma Se levels increased significantly in all diabetic groups compared to basal measurements, being more prominent
in SM group [p(SM3/SM0) = 0.018]. The increase in GSH-Px activities was significant at the end of the second month in SS [p(SS2/SS0) = 0.028], whereas at the end of the third month in SM the value was lower [p(SM3/SM0) = 0.018] and the unsupplemented diabetic control (DC) groups, p(DC3/DC0) = 0.012. Glucose increased significantly only in DC group. Fructosamine increased gradually in all diabetic groups, being
significant in DC and SS groups. At the end of the third month, highest fructosamine levels were observed in SS group, which
were significantly higher than the SM group [p(SM/SS) = 0.010]. In conclusion, Se augmented the antioxidant defense by increasing
GSH-Px activity and this effect was more prominent when Se was supplemented as SM, which exerted positive effects also on
glucose homeostasis. 相似文献
90.
Pirie MD Vargas MP Botermans M Bakker FT Chatrou LW 《American journal of botany》2007,94(6):1003-1016
The plastid trnL-F region has proved useful in molecular phylogenetic studies addressing diverse evolutionary questions from biogeographic history to character evolution in a broad range of plant groups. An important assumption for phylogenetic reconstruction is that data used in combined analyses contain the same phylogenetic signal. The trnL-F region is often used in combined analyses of multiple chloroplast markers. These markers are assumed to contain congruent phylogenetic signal due to lack of recombination. Here we show that trnL-F sequences display a phylogenetic signal conflicting with that of other chloroplast markers in Annonaceae, and we demonstrate that this conflict results from ancient paralogy. TrnL-F copy 2 diverged from trnL-F copy 1 (as used in family-wide phylogenetic analyses) in a direct ancestor of the Annonaceae. Although this divergence dates back 88 million years or more, the exons of both copies appear to be intact. In this case, assuming that (putative) chloroplast markers contain the same phylogenetic signal results in an incorrect topology and an incorrect estimate of ages. Our study demonstrates that researchers should be cautious when interpreting gene phylogenies, irrespective of the genome from which they are presumed to have been sampled. 相似文献