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81.
Molecular Biology Reports - Angiotensin-converting enzyme (ACE, EC 3.4.15.1) in the renin-angiotensin system regulates blood pressure by catalyzing angiotensin I to the vasoconstrictor angiotensin... 相似文献
82.
Wei Zhang Marc Freichel Frank van der Hoeven Peter Paul Nawroth Hugo Katus Florian K?lble Edgar Zitron Vedat Schwenger 《PloS one》2016,11(1)
The water channel aquaporin-1 (AQP1) mediates about 50% ultrafiltration during a 2-hour hypertonic dwell in global AQP1 knockout (AQP1-/-) mice. Although AQP1 is widely expressed in various cell types including mesothelial cells, the ultrafiltration has been assumed to be mediated via endothelial AQP1 of the peritoneum. The partial embryonic lethality and reduced body weight in AQP1-/- mice may reflect potential confounding phenotypic effects evoked by ubiquitous AQP1 deletion, which may interfere with functional analysis of endothelial AQP1. Using a Cre/loxP approach, we generated and characterised endothelial cell- and time-specific AQP1 knockout (AQP1fl/fl; Cdh5-Cre+) mice. Compared to controls, AQP1fl/fl; Cdh5-Cre+ mice showed no difference in an initial clinical and biological analysis at baseline, including body weight and survival. During a 1-hour 3.86% mini-peritoneal equilibration test (mini-PET), AQP1fl/fl; Cdh5-Cre+ mice exhibited strongly decreased indices for AQP1-related transcellular water transport (43.0% in net ultrafiltration, 93.0% in sodium sieving and 57.9% in free water transport) compared to controls. The transport rates for small solutes of urea and glucose were not significantly altered. Our data provide the first direct experimental evidence for the functional relevance of endothelial AQP1 to the fluid transport in peritoneal dialysis and thereby further validate essential predictions of the three-pore model of peritoneal transport. 相似文献
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84.
The effects of magnesium supplementation on plasma magnesium, zinc, and copper levels were determined in young adult tae-kwon-do
athletes and sedentary controls at rest and exhaustion. After a 4-week supplementation period with 10 mg/day/kg Mg, the plasma
magnesium, copper, and zinc levels significantly increased in sedentary and training (90–120 min training 5 days a week) subjects
when compared to nonsupplemented controls (p < 0.05). 相似文献
85.
Vedat Sediroglu nci Eroglu Meral Yücel Lemi Türker Ufuk Gündüz 《Journal of biotechnology》1999,70(1-3):115-124
Hydrogen gas can be produced electrochemically by leading a current through two electrodes immersed in a NaCl solution. Bacteriorhodopsin (BR) a protein found in the purple membrane of Halobacterium halobium, is known to pump protons across the membrane upon illumination. In this study, the effect of BR on photoelectrochemical hydrogen production was investigated. A batch type bio-photoelectrochemical reactor was designed and constructed. The photoelectrochemical hydrogen production experiments were performed with free H. halobium packed cells or immobilised H. halobium cells. The cells were either immobilised in polyacrylamide gel (PAG) or on cellulose acetate membrane (CAM). Experiments were also performed with purple membrane fragments of H. halobium immobilised on cellulose acetate membrane. It was found that the presence of bacteriorhodopsin (BR) in the reactor enhances the hydrogen production rate upon illumination. Immobilisation increased the amount of hydrogen produced per mole of BR. Compared to control experiments without BR, the power requirement of the photoelectrochemical reactor per amount of hydrogen produced decreased fourfold when purple membrane fragments immobilised on CAM were used. The presence of BR regulates the pH of the system, increases the hydrogen production rate and causes light-induced proton dissociation, which lowers the electrical power requirement for the electrochemical conversion. 相似文献
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87.
It is well known that oxidative stress plays an important role in the etiology of epilepsy. We investigated effects of selenium (Se) and topiramate (TPM) combination supplementation on antioxidant and oxidant values in control and patients with epilepsy and refractory epilepsy. For the aim, we used control (n?=?19), epilepsy + TPM (n?=?19), epilepsy + TPM + Se (n?=?15) groups. We also used control (n?=?15), refractory epilepsy (n?=?15), and refractory epilepsy + Se (n?=?8) groups. TPM (0.2 mg/daily) and Se, as sodium selenite (twice daily with 0.1 mg doses), were orally supplemented to the patients for 45 days. Erythrocyte lipid peroxidation levels were higher in refractory epilepsy groups than in control although its level and seizure numbers were decreased in TPM and TPM + Se supplemented groups of the patients. The erythrocyte reduced glutathione (GSH), glutathione peroxidase (GSH-Px), plasma total antioxidant status (TAS), and vitamin E concentration in refractory epilepsy group were lower than in control. However, the erythrocyte and plasma TAS, erythrocyte GSH and GSH-Px, and plasma vitamins A and C values were increased either by Se or Se + TPM in epilepsy and refractory epilepsy groups. There were no effects of TPM and Se on plasma β-carotene values in the groups. In conclusion, TPM and selenium caused protective effects on the epilepsy and refractory epilepsy-induced oxidative injury by inhibiting free radical production and supporting antioxidant redox system. 相似文献
88.
Vedat Ali Yürekli Semih Gürler Mustafa Nazıroğlu Abdülhadi Cihangir Uğuz Hasan Rifat Koyuncuoğlu 《Cellular and molecular neurobiology》2013,33(2):205-212
Parkinson’s disease is an incurable progressive neurological condition caused by a degeneration of dopamine-producing cells characterized by motor and non-motor symptoms. The major mechanisms of the antiepileptic actions of ZNS are inhibition of voltage-gated Na+ channel, T-type voltage-sensitive Ca2+ channel, Ca2+-induced Ca2+ releasing system, and neuronal depolarization-induced glutamate release; and enhancement of release of inhibitory neurotransmitters; however, the detailed mechanism of antiparkinsonian effects of ZNS remains to be clarified. We aimed to investigate to the effect of ZNS on the oxidative stress, cell viability, Ca2+ signaling, and caspase activity that induced by the MPP+ model of Parkinson’s in neuronal PC12 cells. Neuronal PC12 cells were divided into four groups namely, control, ZNS, MPP+, and ZNS+MPP+ groups. The dose and duration of ZNS and MPP+ were determined according to cell viability (MTT) analysis which used to assess the cell viability. The cells in ZNS, MPP+, and ZNS+MPP+ groups were incubated for 5 h with 100 μM ZNS, 10 h with 100 μM MPP+, and 10 h with ZNS and MPP+, respectively. Lipid peroxidation and cytosolic free Ca2+ concentrations were higher in the MPP+ group than in control although their levels were lower in ZNS and the ZNS+MPP+ groups than in control. Reduced glutathione and glutathione peroxidase values were lower in the MPP+ group although they were higher in the ZNS and the ZNS+MPP+ groups than in control. Caspase-3 activity was lower in the ZNS group than in the MPP+ group. In conclusion, ZNS induced modulator effects on the oxidative stress, intracellular Ca2+, and the caspase-3 values in an experimental model of Parkinson disease. 相似文献
89.
Seden Demirci Süleyman Kutluhan Mustafa Nazıroğlu Abdülhadi Cihangir Uğuz Vedat Ali Yürekli Kadir Demirci 《Neurochemical research》2013,38(1):90-97
It has been widely suggested that selenium (Se) deficiency play an important role in the pathophysiology of epilepsy. It has been reported that Se provides protection against the neuronal damage in patients and animals with epilepsy by restoring the antioxidant defense mechanism. The neuroprotective effects of topiramate (TPM) have been reported in several studies but the putative mechanism of action remains elusive. We investigated effects of Se and TPM in neuronal PC12 cell by evaluating Ca2+ mobilization, lipid peroxidation and antioxidant levels. PC12 cells were divided into eight groups namely control, TPM, Se, H2O2, TPM + H2O2, Se + H2O2, Se + TPM and Se + TPM + H2O2. The toxic doses and times of H2O2, TPM and Se were determined by cell viability assay which is used to evaluate cell viability. Cells were incubated with 0.01 mM TPM for 5 h and 500 nM Se for 10 h. Then, the cells were exposed to 0.1 mM H2O2 for 10 h before analysis. The cells in all groups except control, TPM and Se were exposed to H2O2 for 15 min before analysis. Cytosolic Ca2+ release and lipid peroxidation levels were higher in H2O2 group than in control, Se and TPM combination groups although their levels were decreased by incubation of Se and TPM combination. However, there is no difference on Ca2+ release in TPM group. Glutathione peroxidase activity, reduced glutathione and vitamin C levels in the cells were lower in H2O2 group than in control, Se and TPM groups although their values were higher in the cells incubated with Se and TPM groups than in H2O2 groups. In conclusion, these results indicate that Se induced protective effects on oxidative stress in PC12 cells by modulating cytosolic Ca2+ influx and antioxidant levels. TPM modulated also lipid peroxidation and glutathione and vitamin C concentrations in the cell system. 相似文献
90.
Mustafa Nazıroğlu Mehmet Berk Akay Ömer Çelik Muhammed İkbal Yıldırım Erdinç Balcı Vedat Ali Yürekli 《Neurochemical research》2013,38(4):780-788
It has been widely suggested that oxidative stress products play an important role in the pathophysiology of epilepsy. Capparis ovata (C. ovata) may useful treatment of epilepsy because it contains antioxidant flavonoids. The current study was designed to determine the effects of C. ovata on lipid peroxidation, antioxidant levels and electroencephalography (EEG) records in pentylentetrazol (PTZ)-induced epileptic rats. Thirty-two rats were randomly divided into four groups. First group was used as control although second group was PTZ group. Oral 100 and 200 mg/kg C. ovata were given to rats constituting the third and fourth groups for 7 days before PTZ administration. Second, third and forth groups received 60 mg/kg PTZ for induction of epilepsy. Three hours after administration of PTZ, EEG records, brain cortex and blood samples were taken all groups. The lipid peroxidation levels of the brain cortex, number of spikes and epileptiform discharges of EEG were higher in PTZ group than in control and C. ovata group whereas they were decreased by C. ovata administration. Vitamin A, vitamin C, vitamin E and β-carotene concentrations of brain cortex and latency to first spike of EEG were decreased by the PTZ administration although the brain cortex and plasma vitamin concentrations, and brain cortex and erythrocyte glutathione and glutathione peroxidase values were increased in PTZ + 100 and PTZ + 200 mg C. ovata groups. In conclusion, C. ovata administration caused protection against the PTZ-induced brain oxidative toxicity by inhibiting free radical and epileptic seizures, and supporting antioxidant redox system. 相似文献