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391.
Caliskan M Ozcan B Turan C Cuming AC 《Journal of biochemistry and molecular biology》2004,37(3):339-342
Germination is a process which characterized with nescient synthesis of genes. Among the genes synthesized during the germination of wheat embryos, germin genes, proteins and their enzymatic activity were defined. Germin is a water soluble homopentameric glycoprotein which is remarkable resistant to degradation by a broad range of proteases including pepsin. Germin proteins found to have strong oxalate oxidase activity which produces hydrogen peroxide by degrading oxalic acid. The current study, aimed to localize the germin genes, proteins and enzymatic activities in developing coleoptiles which is a rapidly growing protective tissue of leaf primordium and shoot apex. Non-radioactively labeled germin riboprobes were employed to localize germin mRNAs in situ. FITC (Fluorescein isothiocyanate) and alkaline phosphatase linked anti-germin antibodies were used to localize germin proteins under the fluorescence and light microscopy and finally germin enzymatic activity was localized by using appropriate enzyme assay. The results revealed that in coleoptiles germin genes, proteins and their enzymatic activity were predominantly associated with the cells of epidermis and vascular bundle sheath cells. 相似文献
392.
Serkan Demir Zuhal Yolcu Ömer Andaç Orhan Büyükgüngör Turan K. Yazıcılar 《Journal of molecular modeling》2010,16(9):1509-1518
A dinuclear centrosymmetric copper(II) complex with the formula [Cu2(μ-maa)4(maaH)2] has been synthesized and experimentally characterized by IR, electronic spectroscopy, and X-ray single-crystal diffractometry.
Starting from experimental X-ray geometry and using antiferromagnetic singlet ground state, gas phase geometry optimization
was performed by density functional hybrid (B3LYP) method with 6-31G(d) and LANL2DZ basis sets. Gas-phase vibrational frequencies
and single point energy (SPE) calculations have been carried out at the geometry-optimized structure. Molecular electrostatic
potential calculated at the optimized geometry and natural bond orbital analysis data have been extracted from SPE output.
The gas-phase electronic transitions of the title complex were investigated by the time dependent-density functional theory
(TD-DFT) approach with the same theory employing LANL2DZ basis set. Also the calculated UV-Vis based upon TD-DFT results and
IR spectra were simulated for comparison with the experimental ones. 相似文献
393.
Intestinal epithelium secretes novel unilamellar membranes having characteristics similar to lung surfactants and thus has been named Surfactant-like particles (SLP). The chemical analysis of the membranes revealed cholesterol/phospholipid molar ratio of 0.68-0.78, which is much distinct from that of the underlying microvillus membranes (1.34-1.49). The membrane contains 4-6 proteins with a molar weight of 30-120 kDa and is enriched with alkaline phosphatase, contains low amounts of disaccharidases but no Na+, K(+)-ATPase activity. The secretion of SLP is stimulated by fat feeding. Chronic ethanol ingestion also induces the formation of SLP in rat intestine. A number of physiological functions have been attributed to SLP, which include: (i) as a protective lubricant in intestinal lumen, (ii) a role in triacylglycerol transport, (iii) as a vehicle for the transport of luminal proteins into blood, (iv) as a stratum for the adhesion of microorganisms in intestinal lumen, and (v) a role in trans-signalling mechanism across the basolateral surface of enterocytes. 相似文献
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396.
Effect of astaxanthin and aluminum chloride on erythrocyte G6PD and 6PGD enzyme activities in vivo and on erythrocyte G6PD in vitro in rats 下载免费PDF全文
Yusuf Temel Aydın Şükrü Bengü Hurrem Turan Akkoyun Mahire Akkoyun Mehmet Ciftci 《Journal of biochemical and molecular toxicology》2017,31(10)
In this study, we investigated the effect of astaxanthin (Ast) and aluminum (Al) on the erythrocyte glucose‐6‐phosphate dehydrogenase (G6PD) and 6‐phosphogluconate dehydrogenase (6PGD) enzymes activities in vivo and on G6PD enzyme in vitro in rats. For in vitro studies, G6PD enzyme was purified from rat erythrocyte by using 2′,5′‐ADP‐Sepharose 4B affinity gel. The effects of Ast and Al3+ ion were investigated on the purified enzyme. It was determined that Ast increased the enzyme activity, whereas Al3+ inhibited the enzyme activity noncompetitively (IC50 values; 0.679 mM, Ki values 1.32 mM). For in vivo studies, the rats were divided into the groups: control (Cont.), Al, Ast, and Al + Ast. The last three groups were compared with the control group. In Al group, a significant degree of inhibition was observed in the activity of G6PD and 6PGD enzymes when compared with the control group (P < 0.05), whereas there was an increase in the activities of G6PD and 6PGD enzymes in Ast and Al + Ast groups (P < 0.05). 相似文献
397.
High glucose and increased oxidative stress levels are the known important mediators of diabetic nephropathy. However, the effects of these mediators on tissue damage basically due to extracellular matrix expansion in mesangial cells have yet to be fully examined within the context of early stage diabetic nephropathy. In this study, we attempted to characterize changes in mesangial cells of streptozotocin-induced diabetic rats with a comparative investigation of kidney tissue by using different microscopy techniques. The serum levels of urea and creatinine of diabetic rats, as biomarkers of kidney degeneration, decreased significantly compared to those of age-matched controls. In diabetic rats, there are increased malondialdehyde and oxidized-glutathione levels as well as reduced-glutathione and glutathione-peroxidase activity levels in renal tissue compared to those of the controls. By using light and electron microscopies, we showed that there were marked thickening in Bowman’s membrane and glomerular capillary wall, increased amount of extracellular matrix often occupying Bowman’s space, degenerations in tubules, an increased number of mesangial cells in the network of glomerular capillary walls, and increased amount of lipid accumulation in proximal tubules in the renal tissue of diabetic rats. Our confocal microscopy data confirmed also the presence of irregularity and widened in glomerular capillaries, their attachment to the Bowman’s capsule, degenerated heterochromatin, thickening in foci of glomerular basement membrane, and marked increase in mesangial cells. These results suggest that a detailed structural investigation of kidney tissue provides further information on the important role of mesangial cells in pathogenesis of diabetic nephropathy. 相似文献
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399.
The continuous production of 1,3-propanediol (1,3-PDO) was investigated with Clostridium beijerinckii NRRL B-593 using raw glycerol without purification obtained from a biodiesel production process. Ceramic rings and pumice
stones were used for cell immobilization in a packed-bed bioreactor. For comparison purpose, a control bioreactor with suspended
culture was also run. The effect of hydraulic retention time (HRT) on the production of 1,3-PDO in both immobilized and suspended
bioreactors were also investigated. The study revealed that HRT is an important factor for both immobilized and suspended
systems and a HRT of 2 h is the best one in terms of volumetric production rate (g 1,3-PDO/L/h). Furthermore, cell immobilization
had also obvious benefits especially for the robustness and the reliability of the production. The results indicated that
cell immobilization achieved a 2.5-fold higher productivity in comparison to suspended cell system. Based on our results,
continuous production of 1,3-PDO with immobilized cells is an efficient method, and raw glycerol can be utilized without any
pretreatment. 相似文献
400.
Gender-based acute outcome in percutaneous coronary intervention of chronic total coronary occlusion
J. E. Guelker L. Bansemir R. Ott K. Kuhr B. Koektuerk R. G. Turan H. G. Klues A. Bufe 《Netherlands heart journal》2017,25(5):304-311