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291.
292.
Cytotechnology - Topical formulations containing 1–2% of Pinus brutia bark extract and Pycnogenol® have been prepared to investigate the effect of flavonoids on the stability of O/W... 相似文献
293.
Ozlem Sacan Ismet Burcu Turkyilmaz Bertan Boran Bayrak Ozgur Mutlu Nuriye Akev Refiye Yanardag 《Biometals》2016,29(2):239-248
Zinc (Zn) is a component of numerous enzymes that function in a wide range of biological process, including growth, development, immunity and intermediary metabolism. Zn may play a role in chronic states such as cardiovascular disease and diabetes mellitus. Zn acts as cofactor and for many enzymes and proteins and has antioxidant, antiinflammatory and antiapoptotic effects. Taking into consideration that lung is a possible target organ for diabetic complications, the aim of this study was to investigate the protective role of zinc on the glycoprotein content and antioxidant enzyme activities of streptozotocin (STZ) induced diabetic rat tissues. Female Swiss albino rats were divided into four groups. Group I, control; Group II, control + zinc sulfate; Group III, STZ-diabetic; Group IV, diabetic + zinc sulfate. Diabetes was induced by intraperitoneal injection of STZ (65 mg/kg body weight). Zinc sulfate was given daily by gavage at a dose of 100 mg/kg body weight every day for 60 days to groups II and IV. At the last day of the experiment, rats were sacrificed, lung tissues were taken. Also, glycoprotein components, tissue factor (TF) activity, protein carbonyl (PC), advanced oxidative protein products (AOPP), hydroxyproline, and enzyme activities in lung tissues were determined. Glycoprotein components, TF activity, lipid peroxidation, non enzymatic glycation, PC, AOPP, hydroxyl proline, lactate dehydrogenase, catalase, superoxide dismutase, myeloperoxidase, xanthine oxidase, adenosine deaminase and prolidase significantly increased in lung tissues of diabetic rats. Also, glutathione levels, paraoxonase, arylesterase, carbonic anhydrase, and Na+/K+- ATPase activities were decreased. Administration of zinc significantly reversed these effects. Thus, the study indicates that zinc possesses a significantly beneficial effect on the glycoprotein components and oxidant/antioxidant enzyme activities. 相似文献
294.
Abakay A Gokalp O Abakay O Evliyaoglu O Sezgi C Palanci Y Ekici F Karakus A Tanrikulu AC Ayhan M 《Biological trace element research》2012,145(2):151-157
The aim of this study was to investigate the respiratory function disorders that could be related to dust exposure during
the production of copper mine in copper mineworkers (CMWs). The study included 75 male CMWs (mean age, 32.0 ± 7.1 years, 58.6%
smokers) and 75 male age- and smoking status-matched healthy control subjects. Serum Cu level was significantly higher in
the CMW group (0.80 ± 0.62 μg/ml) than the control group (0.60 ± 0.39 μg/ml) (p = 0.017). Significant negative correlations were found between serum Cu level and forced expiratory volume in first second
(r = −0.600; p < 0.001) and between serum Cu level and forced vital capacity (r = −0.593; p = <0.001) in CMWs. Serum Cu level was significantly higher in the restrictive type pulmonary function disorders group (1.36 ± 0.62 μg/ml)
than obstructive type (0.90 ± 0.55 μg/ml) and normal pulmonary function pattern group (0.53 ± 0.43 μg/ml) (p < 0.001). Patients with radiological parenchymal abnormalities had significantly higher serum copper levels than those without
abnormalities (1.53 ± 0.52 vs. 0.71 ± 0.52 μg/ml, respectively; p = 0.002). In conclusion, result of the study has shown a negative association between pulmonary functions disorders and radiological
abnormalities and serum Cu levels in CMWs. 相似文献
295.
Kemal?O. Yariz Duygu Duman Celia?Zazo Seco Julia Dallman Mingqian Huang Theo?A. Peters Asli Sirmaci Na Lu Margit Schraders Isaac Skromne Jaap Oostrik Oscar Diaz-Horta Juan?I. Young Suna Tokgoz-Yilmaz Ozlem Konukseven Hashem Shahin Lisette Hetterschijt Moien Kanaan Anne?M.M. Oonk Yvonne?J.K. Edwards Huawei Li Semra Atalay Susan Blanton Alexandra?A. DeSmidt Xue-Zhong Liu Ronald?J.E. Pennings Zhongmin Lu Zheng-Yi Chen Hannie Kremer Mustafa Tekin 《American journal of human genetics》2012,91(5):872-882
296.
Hulya Yilmaz-Aydogan Ozlem Kurnaz Ozlem Kucukhuseyin Basak Akadam-Teker Ozlem Kurt Allison Pinar Eronat Atike Tekeli Zehra Bugra Oguz Ozturk 《Gene》2013
Background
The aim of this study was to investigate the individual or combined effects of PPARA-L162V, PPARG-C161T and APOE polymorphisms on hyperlipidemia in coronary heart disease (CHD) patients.Methods
Our study included 223 patients with CHD (103 with type 2 diabetes (T2DM), 120 without diabetes) and 101 controls. All genotypes were determined by PCR–RFLP technique.Results
Genotypic and allelic distributions of PPARA-L162V polymorphism were similar between study and control groups (p > 0.05). The serum total-cholesterol (TC) and LDL-cholesterol (LDL-C) levels were higher in PPARA-V162 allele carriers in non-diabetic CHD patients (p = 0.007 and p = 0.038, respectively). The increasing effect of the PPARA-V162 allele on serum TC and LDL-C levels was weakened with the presence of PPARG-161T allele in the non-diabetic CHD patients. The ApoE4–PPARA-V162 allelic combination of the ApoE/PPARA genes was found to be more frequent in diabetic CHD patients independent of serum lipids (p = 0.035).Conclusions
The PPARA V162 allele has an increasing effect on TC and LDL-C levels and this effect was reduced by carrying PPARG T161 allele in non-diabetic CHD patients. On the other hand, the V162 allele may be associated with an increased risk of CHD in diabetic CHD patients due to the presence of ApoE4 allele independent of serum lipids. We suggest that the PPARA L162V polymorphism may have diverse effects on serum lipids and CHD risk depends on the presence of T2DM. 相似文献297.
Drosophila mei-9 is essential for several DNA repair and recombination pathways, including nucleotide excision repair (NER), interstrand crosslink repair, and meiotic recombination. To better understand the role of MEI-9 in these processes, we characterized 10 unique mutant alleles of mei-9. These include a P-element insertion that disrupts repair functions but not the meiotic function; three nonsense mutations, one of which has nearly wild-type levels of protein; three missense mutations, one of which disrupts the meiotic function but not repair functions; two small in-frame deletions; and one frameshift. 相似文献
298.
Ruth Nussinov Chung-Jung Tsai Serena Muratcioglu Hyunbum Jang Attila Gursoy Ozlem Keskin 《Expert review of proteomics》2015,12(6):669-682
Illustrated here is the critical role of oncogenic KRAS in the initiation of cancer through deregulation of the G1 cell cycle, and elements and scenarios taking place under physiological conditions and in KRAS-driven cancer. Raf, PI3K and RalGDS are major K-Ras effectors. They bind at the same Ras site. What decides the cell selection among them? This temporal and spatial decision is critical since in some cellular context the outcome of their signaling pathways may oppose each other. Key among them is the concentration of calcium/calmodulin, negative feedback loops, where a downstream member of the pathway inhibits its upstream activator and cross-inhibition, where inhibition entails blocking another pathway. These three elements, in addition to spatial restrictions by K-Ras-membrane interactions, are not independent; they integrate to provide blueprints for cell decisions. Importantly, elucidation of signaling requires not only K-Ras binary interactions; but the structures and dynamics of its multiprotein complexes. 相似文献
299.
Formation and function of flavin anion radical in cryptochrome 1 blue-light photoreceptor of monarch butterfly 总被引:3,自引:0,他引:3
Song SH Oztürk N Denaro TR Arat NO Kao YT Zhu H Zhong D Reppert SM Sancar A 《The Journal of biological chemistry》2007,282(24):17608-17612
The monarch butterfly (Danaus plexippus) cryptochrome 1 (DpCry1) belongs in the class of photosensitive insect cryptochromes. Here we purified DpCry1 expressed in a bacterial host and obtained the protein with a stoichiometric amount of the flavin cofactor in the two-electron oxidized, FAD(ox), form. Exposure of the purified protein to light converts the FAD(ox) to the FAD*(-) flavin anion radical by intraprotein electron transfer from a Trp residue in the apoenzyme. To test whether this novel photoreduction reaction is part of the DpCry1 physiological photocycle, we mutated the Trp residue that acts as the ultimate electron donor in flavin photoreduction. The mutation, W328F, blocked the photoreduction entirely but had no measurable effect on the light-induced degradation of DpCry1 in vivo. In light of this finding and the recently published action spectrum of this class of Crys, we conclude that DpCry1 and similar insect cryptochromes do not contain flavin in the FAD(ox) form in vivo and that, most likely, the [see text] photoreduction reaction is not part of the insect cryptochrome photoreaction that results in proteolytic degradation of the photopigment. 相似文献
300.