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51.
Zeliha Selamoglu Talas Ilknur Ozdemir Yetkin Gok Burhan Ates Ismet Yilmaz 《Regulatory peptides》2010,159(1-3):137-141
Synthetic organoselenium compounds can be tailored to achieve greater chemopreventive efficacy with minimal toxic side effects by structural modifications. Two organoselenium compounds (Se I and Se II) were synthesized and evaluated for their antihypertensive and therapeutic properties by adrenomedullin (ADM) levels and tyrosine hydroxylase (TH) activity assays in rat heart tissue. 7,12-Dimethylbenz[a]anthracene (DMBA) is known to generate DNA-reactive species during their metabolism, which may enhance oxidative stress in cells. TH is thought to be a rate-limiting enzyme in the biosynthesis of catecholamines. ADM, a potent endogenous vasodilating and natriuretic peptide, may play an important role in the pathophysiology of chronic heart failure. The effects of Se I and Se II were investigated on TH activity, ADM and total RNA levels in the hearts of albino Wistar rats. TH activity was found to be increased significantly by the effect of DMBA (P < 0.05). This increase was restricted in the Se I and Se II treated groups. ADM level was found to be decreased insignificantly by the effect of DMBA (P > 0.05). Total RNA level was found to be decreased significantly by the effect of DMBA (P < 0.05). This study demonstrates that synthetic organoselenium compounds can regulate DMBA-induced stress related changes in rat heart. 相似文献
52.
Thermal stability of carbonic anhydrase (CA) immobilized within polyurethane (PU) foam was investigated. The catalytic activity of the enzyme was estimated by using p‐nitrophenyl acetate (p‐NPA) as the substrate in tris buffer containing 10% acetonitrile. The immobilized CA was stable during the repeatable washings and stability tests over 45 days stored in tris buffer at ambient conditions indicating that the CA was covalently attached to the polyurethane (PU) foam by crosslinking. The immobilized CA was found to be 98% stable below 50°C, whereas a drastic decrease was seen at temperatures between 50 and 60°C. The optimum temperature for the immobilized CA was found to be 45°C and it lost its activity completely at 60°C. Thermal deactivation energies for the free and immobilized CA were estimated to be 29 and 86 kcal/mol, respectively. The association of unfolded CA with the polymeric backbone chains of the PU foam was also addressed. It was concluded that the immobilized CA was highly stable at temperatures less than 50°C and could be used in biomimetic CO2 sequestration processes. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010 相似文献
53.
54.
Ferahman M Unal E Sakoglu N Ersoy YE As A Ozdemir S 《Biological trace element research》2003,91(1):89-94
Metal ions are required as active components of several proteins, including pancreatic enzymes, and they can play important roles in the etiopathogenesis of acute pancreatitis. In the present study, we measured the concentrations of zinc (Zn) and copper (Cu) in both serum and pancreatic tissue, as markers of trace element status in an experimental acute pancreatitis model. Twenty-four male Wistar rats were divided into two groups: the experimental group (N=24) and the control group (N=10). Acute pancreatitis was induced by injection of 48% ethyl alcohol into the common biliary duct. The animals were sacrificed 24 h later to detect the concentrations of Zn and Cu. There was no significant difference in tissue Zn and Cu concentrations between control and experimental groups (p<0.05). However, in the acute pancreatitis group, serum Zn and Culevels were very significantly lower (p<0.001 and p<0.0001, respectively). In conclusuion, these findings suggested that altered mineral metabolism in serum and pancreatic tissue may have contributed to the pathophysiology of acute pancreatitis. 相似文献
55.
Türk AO Yilmaz M Kivanç M Türk H 《Zeitschrift für Naturforschung. C, Journal of biosciences》2003,58(11-12):850-854
In this study, the antimicrobial activity of the acetone, diethyl ether and ethanol extracts of the lichen Cetraria aculeata has been investigated. The extracts were tested against twelve bacteria and eight fungi and found active against Escherichia coli, Staphylococcus aureus, Aeromonas hydrophila, Proteus vulgaris, Streptococcus faecalis, Bacillus cereus, Bacillus subtilis, Pseudomonas aeruginosa, Listeria monocytogenes. No antimicrobial activity against the fungi was detected. It was determined that only one substance in the extracts has antimicrobial activity and it was characterized as protolichesterinic acid. The MICs of the extracts and protolichesterinic acid were also determined. 相似文献
56.
Heavy metal biosorption by biomass of Ochrobactrum anthropi producing exopolysaccharide in activated sludge 总被引:5,自引:0,他引:5
The removal of chromium, cadmium and copper, toxic metals of high environmental priority due to their toxicity, from dilute aqueous solutions has been studied in the present work, applying a dead exopolysaccharide producing bacterium, Ochrobactrum anthropi, isolated from activated sludge. Particularly, the effect of pH, metal concentration and the effects of contact time were considered. Optimum adsorption pH values of chromium(VI), cadmium(II) and copper(II) were 2.0, 8.0 and 3.0 respectively. Experimental results also showed the influence of initial metal concentration on the metal uptake for dried biomass. Both the Freundlich and Langmuir adsorption models were suitable for describing the short-term biosorption of chromium(VI), cadmium(II) and copper(II) by O. anthropi. 相似文献
57.
Protective effect of selenium treatment on diabetes-induced myocardial structural alterations 总被引:2,自引:0,他引:2
One of the main causes leading to mortality in diabetes is myocardial disease. Using streptozotocin (STZ)-induced diabetic
animals, it has been possible to characterize diabetes-induced myocardial abnormalities. Interstitial and microvascular disorders
are known to be a characteristic part of the diabetic cardiomyopathy and partly resist insulin therapy. Because diabetic damage
is partly attributed to oxidative stress, antioxidant treatment may be able to reduce this damage. The aim of this study was
to investigate the cardioprotective effect of sodium selenite, known as an antioxidant agent. The diabetes was induced by
ip injection of 50 mg/kg body wt STZ. The duration of diabetes was 5 wk. The protected group received (ip) 5 μmol/kg body
wt/d sodium selenite (Na2SeO3) over 4 wk following diabetes induction. Electron and light microscopic morphometry of heart samples revealed typical diabetic
alterations consisting in an increase in collagen content, vacuolation, diminishing of the cardiomyocyte diameter, alteration
in myofilaments and Z-lines of myofibers, and myofibrillary degeneration. Sodium selenite treatment could prevent the loss
of myofibrills and reduction of myocyte diameter. In the sodium-selenite-treated diabetic rat heart, alterations of the discus
intercalaris and nucleus were corrected, and degenerations seen in myofilaments and Z-lines were reversed by this treatment.
Under these findings, one can suggest that sodium selenite treatment may alleviate late diabetic complications when it is
used under control conditions. 相似文献
58.
Selenium (Se) has long been recognized as both an essential mammalian nutrient and a hazardous element. Sodium selenite is
commonly used as a dietary supplement for the treatment of Se deficiency. On the other hand, chronic Se toxicity has been
demonstrated to affect the major organs, including the heart, in experimental animals.
This study examines the effects of high concentrations of extracellular selenite (in the range of 0.001–1 mM) application into the recording bath on the electrical properties of rat papillary muscles. Conventional glass semifloating
microelectrodes were used to record intracellular action potentials (APs) in isolated rat papillary muscles. The amplitude
of APs and the resting membrane potential of papillary muscles were not changed following a 20-min selenite (1 mM) application compared to the first minute of its application. Freshly isolated ventricular myocytes by an enzymatic method
were used to determine the selenite-induced alterations in Na+ currents. Na+ currents, measured at 22°C, by the whole-cell patch-clamp technique, decreased by 38±8% in the presence of 1 mM selenite for 5 min. These selenite-induced effects were not reversed, but are restored by dithiothreitol (1 mM).
These results demonstrated that toxic concentrations of selenite induced a significant shortening in AP duration as a result
of an increase in the rate of repolarization. Our findings also suggest that a decrease in Na+ currents, in addition to Ca2+ currents, may play a role in the shortening of AP duration in rat papillary muscles. 相似文献
59.
Anatomicohistologic study of the retaining ligaments of the face and use in face lift: retaining ligament correction and SMAS plication 总被引:1,自引:0,他引:1
Ozdemir R Kilinç H Unlü RE Uysal AC Sensöz O Baran CN 《Plastic and reconstructive surgery》2002,110(4):1134-47; discussion 1148-9
Plastic surgeons have sought to improve nasolabial folds, jowls, jaw lines, and cervical contour with face-lifting procedures that are abundant in the literature. The retaining ligaments of the face support facial soft tissue in normal anatomic position, resisting gravitational change. As this ligamentous system attenuates, facial fat descends into the plane between the superficial and deep facial fascia, and the stigmata of facial age develop. In this study, surgical correction of the retaining ligaments and plication of the superficial musculoaponeurotic system (SMAS) to reposition the structures that have descended with gravitation are discussed. The anatomy of the facial retaining ligaments was studied in 22 half-faces of 11 fresh cadavers, and the localization, extension, and width of the ligaments were examined macroscopically and histologically. Surgical correction of the retaining ligaments and plication of the SMAS have been accomplished in 27 face-lift patients with this anatomicohistologic study taken into consideration. There was hematoma in one patient at the cheek region and a permanent dimple caused by postoperative edema in two patients, with a localization of one zygomatic and two parotidomasseteric ligaments. In one patient, hypesthesia in the mandibular nerve region was seen, which remitted at 14 weeks. There were no other complications, and with a follow-up of 24 months, excellent aesthetic results and a high level of patient satisfaction were encountered. 相似文献
60.
Reconstruction of facial defects with superficial temporal artery island flaps: a donor site with various alternatives 总被引:11,自引:0,他引:11
Ozdemir R Sungur N Sensöz O Uysal AC Ulusoy MG Ortak T Baran CN 《Plastic and reconstructive surgery》2002,109(5):1528-1535
Color and texture match is crucial in reconstruction of facial tissue defects. Between March of 1997 and July of 2000, island flaps based on the parietal, anterofrontal, centrofrontal, posterofrontal, and superior auricular branches of the superficial temporal artery were used in the reconstruction of tissue defects localized on different regions of the face in 28 patients. According to the size and the location of the defect, the flap was selected. There were 15 male patients and 13 female patients, with ages ranging between 19 and 74 years. In six of the flaps, venous congestion was observed. Because of the elevation of the eyebrow on the flap side, three patients required a sling to the opposite eyebrow. Excellent color and tissue match and transfer of hair-bearing tissue to the eyebrow and beard areas were achieved with no other complications. Satisfactory aesthetic results were gained. 相似文献