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81.
Ahmet R. Oğuz 《The Journal of membrane biology》2013,246(3):183-188
Chalcalburnus tarichi is an anadromous cyprinid fish that has adapted to extreme conditions (salinity 22 ‰, pH 9.8 and alkalinity 153 mEq × l?1) in Lake Van in eastern Turkey. Changes in immunoreactivity of Na+/K+-ATPase in gill tissue and osmolarity and ion levels in plasma were investigated in C. tarichi during reproductive migration. Physicochemical characteristics and ion levels in Lake Van were high compared freshwater. Plasma osmolality and plasma ion concentrations ([Na+], [K+] and [Cl?]) increased after transfer from freshwater to Lake Van. The mitochondria-rich (MR) cells of the gill were stained in both filament and lamellar epithelia of C. tarichi by immunocytochemistry with a specific antiserum for Na+/K+-ATPase in river fish samples. Density and area of MR cells were decreased in lake-adapted fishes. These results indicated that freshwater acclimation capacity is correlated with the size and distribution of MR cells in C. tarichi, in contrast to many teleost fishes. 相似文献
82.
Effects of Naringenin on Oxidative Stress and Histopathological Changes in the Liver of Lead Acetate Administered Rats 下载免费PDF全文
Ahmet Ozkaya Zafer Sahin Uzeyir Dag Mustafa Ozkaraca 《Journal of biochemical and molecular toxicology》2016,30(5):243-248
Lead has several adverse effects on the body due to one of the environmental pollutants. We aimed to determine the effects of naringenin on the oxidative stress and the hepatic damage against lead acetate treatment in the liver of male rats. Naringenin was administered by orogastric gavage (50 mg/kg) and lead acetate was given as daily 500 parts per million in drinking water for 4 weeks. Lead and antioxidant activities were measured, and histopathological evaluation was performed in the liver. Lead concentrations, malondialdehyde, and antioxidant activity were restored by the naringenin. The grade of necrosis, hydropic degeneration, and hepatic cord disorganization was decreased by the naringenin. However, there were no differences in the degree of sinusoidal congestion, hepatic steatosis, and capsular fibrosis between lead acetate and naringenin + lead acetate groups. We can suggest that naringenin has antioxidant and chelating effects in the liver. Nevertheless, this effect is not enough against the lead acetate induced hepatic injury. 相似文献
83.
Fulya Tekşen Bekir Sitki Şayli Ahmet Aydin Ahmet Sayal Aşkin Işimer 《Biological trace element research》1998,63(2):123-127
Down syndrome is the most common cause of mental retardation, affecting 1 in 700–800 liveborn infants. Although numerous biochemical
abnormalities accompanying the syndrome have not yet been completely clarified, the antioxidant defense system enzymes have
shown to be altered due to increased gene dosage on chromosome 21 and overproduction of superoxide dismutase (SOD-1 or Cu/Zn
SOD). The purpose of this study was to investigate the activities of SOD-1 and glutathione peroxidase (GSH-Px) enzymes and
the levels of their cofactors zinc (Zn), copper (Cu) and selenium (Se) in plasma of 20 Down syndrome patients.
In comparison with age and sex-matched controls (n=15), plasma GSH-Px, SOD, and Cu levels were significantly decreased in the patient group, but Zn and Se concentrations remained
unchanged.
This study was presented as a poster in 29th Annual Meeting of European Society of Human Genetics held in Genoa in May, 1997. 相似文献
84.
Biosynthesis of silver nanoparticles (AgNPs) using microorganisms is an important application of nanobiotechnology and green chemistry because of interest by pharmaceutical and food manufacturers. In this study, biosynthesis of AgNPs by a novel Bacillus strain isolated from a soil sample from Sakarya district in Turkey was investigated. Biosynthesis was performed using cell-free supernatant of the bacterium following 24?h growth. Effects of varying AgNO3 concentration (1–10?mM), pH (5–10), and temperature (30–40°C) on the synthesis of AgNPs were determined. Formation of AgNPs was monitored by UV–VIS spectroscopy. Field emission scanning electron microscopy was used to compare morphologies among the various culture conditions. The peaks created by surface plasmon resonance (SPR) of metals were obtained only at 4 and 6?mM AgNO3 concentrations and the maximum concentration for the biosynthesis was observed at 6?mM. The highest yield was achieved at pH 10 and larger nanoparticles were obtained at this pH. The optimum temperatures for biosynthesis were 33 and 37°C. Fourier transform infrared spectroscopy analysis and transmission electron microcopy images confirmed that the proteins served as capping. Energy-dispersive spectroscopy analysis validated the formation of AgNPs. AgNPs exhibited antibacterial activity toward Gram-positive and Gram-negative pathogens. 相似文献
85.
Sinem Helvacıoğlu Mohammad Charehsaz Etil Güzelmeriç Mehmet Ali Oçkun İrem Ayran Hasan Kırmızıbekmez Yüksel Kan Ahmet Aydın Erdem Yeşilada 《化学与生物多样性》2021,18(10):e2000936
The antioxidant and mutagenic/antimutagenic activities of the fixed oils from Nigella sativa (NSO) and Nigella damascena (NDO) seeds, obtained by cold press-extraction from the cultivar samples, were comparatively investigated for the first time. The antimutagenicity test was carried out using classical and modified Ames tests. The fatty acid composition of the fixed oils was characterized by gas chromatography–mass spectrometry (GC-MS) while the quantification of thymoquinone in the fixed oils was determined by UPC2. The main components of the NSO and NDO were found to be linoleic acid, oleic acid, and palmitic acid. The results of the Ames test confirmed the safety of NSO and NDO from the viewpoint of mutagenicity. The results of the three antioxidant test methods were correlated with each other, indicating NDO as having a superior antioxidant activity, when compared to the NSO. Both NSO and NDO exhibited a significant protective effect against the mutagenicity induced by aflatoxin B1 in Salmonella typhimurium TA98 and TA100 strains. When microsomal metabolism was terminated after metabolic activation of the mycotoxin, a significant increase in antimutagenic activity was observed, suggesting that the degradation of aflatoxin B1 epoxides by these oils may be a possible antimutagenic mechanism. It is worthy to note that this is the first study to assess the mutagenicity of NSO and NDO according to the OECD 471 guideline and to investigate antimutagenicity of NDO in comparison to NSO against aflatoxin. 相似文献
86.
Levetiracetam (LEV), a new anticonvulsant agent primarily used to treat epilepsy, has been used in pain treatment but the cellular mechanism of this action remains unclear. This study aimed to investigate effects of LEV on the excitability and membrane depolarization-induced calcium signaling in isolated rat sensory neurons using the whole-cell patch clamp and fura 2-based ratiometric Ca(2+)-imaging techniques. Dorsal root ganglia (DRG) were excised from neonatal rats, and cultured following enzymatic and mechanical dissociation. Under current clamp conditions, acute application of LEV (30 μM, 100 μM and 300 μM) significantly increased input resistance and caused the membrane to hyperpolarize from resting membrane potential in a dose-dependent manner. Reversal potentials of action potential (AP) after hyperpolarising amplitudes were shifted to more negative, toward to potassium equilibrium potentials, after application of LEV. It also caused a decrease in number of APs in neurons fired multiple APs in response to prolonged depolarization. Fura-2 fluorescence Ca(2+) imaging protocols revealed that HiK(+) (30 mM)-induced intracellular free Ca(2+) ([Ca(2+)](i)) was inhibited to 97.8 ± 4.6% (n = 17), 92.6 ± 4.8% (n = 17, p < 0.01) and 89.1 ± 5.1% (n = 18, p < 0.01) after application of 30 μM, 100 μM and 300 μM LEV (respectively), without any significant effect on basal levels of [Ca(2+)](i). This is the first evidence for the effect of LEV on the excitability of rat sensory neurons through an effect which might involve activation of potassium channels and inhibition of entry of Ca(2+), providing new insights for cellular mechanism(s) of LEV in pain treatment modalities. 相似文献
87.
There is growing awareness that endocytic trafficking plays a critical role in cell–cell communication during animal development. We are beginning to understand how endocytosis can initiate, modulate or terminate signaling. In contrast, our knowledge of the mechanisms involved in secreting signaling peptides remains more limited, particularly when it comes to secretion at the apical surface in epithelial cells. In this study, we review the mechanisms that control secretion in Caenorhabditis elegans , focusing on the role of Patched family members and the V0 complex of the vacuolar-adenosine triphosphatase (V-ATPase) in secreting Hedgehog-related peptides and of MIG-14/Wls and the retromer complex in secreting EGL-20/WNT. 相似文献
88.
Ahmet Gül Huri Ozdogan Burak Erer Serdal Ugurlu Ozgur Kasapcopur Nicole Davis Serhan Sevgi 《Arthritis research & therapy》2015,17(1)
IntroductionThis open-label pilot study aimed to investigate the efficacy of canakinumab in colchicine-resistant familial Mediterranean fever (FMF) patients.MethodPatients with one or more attacks in a month in the preceding 3 months despite colchicine were eligible to enter a 30-day run-in period. Patients who had an attack during the first run-in period advanced to a second 30-day period. At the first attack, patients started to receive three canakinumab 150 mg subcutaneous injections at 4-week intervals, and were then followed for an additional 2 months. Primary efficacy outcome measure was the proportion of patients with 50 % or more reduction in attack frequency. Secondary outcome measures included time to next attack following last canakinumab dose and changes in quality of life assessed by SF-36.ResultsThirteen patients were enrolled in the run-in period and 9 advanced to the treatment period. All 9 patients achieved a 50 % or more reduction in attack frequency, and only one patient had an attack during the treatment period. C-reactive protein and serum amyloid A protein levels remained low throughout the treatment period. Significant improvement was observed in both physical and mental component scores of the Short Form-36 at Day 8. Five patients had an attack during the 2-month follow-up, occurring median 71 (range, 31 to 78) days after the last dose. Adverse events were similar to those observed in the previous canakinumab trials.ConclusionCanakinumab was effective at controlling the attack recurrence in patients with FMF resistant to colchicine. Further investigations are warranted to explore canakinumab’s potential in the treatment of patients with colchicine resistant FMF.
Trial registration
ClinicalTrials.gov . Registered 16 March 2010. NCT01088880Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0765-4) contains supplementary material, which is available to authorized users. 相似文献89.
Zafer Sahin Ahmet Ozkaya Gokhan Cuce Mirac Uckun Ertan Yologlu 《Journal of biochemical and molecular toxicology》2017,31(9)
Testis tissue is prone to oxidation because its plasma membrane contains many polyunsaturated fatty acids. Naringenin is a plant‐derived natural flavonoid. We investigated the possible ameliorative role of naringenin on the hydrogen peroxide (H2O2)‐induced testicular damage in Wistar rats. Animals received 12 mg/kg H2O2 by intraperitoneal injection, and 50 mg/kg naringenin via orogastric gavage for 4 weeks. In the H2O2 group, the testis malondialdehyde level increased, while the amount of reduced glutathione, glutathione transferase activities, and the testis weight decreased. There were severe testicular damages in the H2O2 group otherwise their grade were less in the naringenin + H2O2 group. However, the serum testosterone concentrations decreased in both the H2O2 and the naringenin + H2O2 groups. The testicular zinc and calcium levels reduced in the H2O2‐treated rats. In conclusion, the administration of H2O2 caused oxidative stress in the testes and naringenin supplementation decreased the H2O2‐induced effects, except for changes in testosterone levels. 相似文献
90.