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131.
Orhan I Naz Q Kartal M Tosun F Sener B Choudhary MI 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(9-10):684-688
In the current study, a number of alkaloids including retamine, cytisine, and sparteine (quinolizidine-type), yohimbine and vincamine (indole-type), scopolamine and atropine (tropane-type), colchicine (tropolone-type), allantoin (imidazolidine-type), trigonelline (pyridine-type) as well as octopamine, synephrine, and capsaicin (exocyclic amine-type) were tested in vitro for their inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) at 1 mg/ml concentration by the Ellman method using an ELISA microplate reader. Among the alkaloids tested, only capsaicin exerted a remarkable inhibitory effect towards both AChE and BChE [(62.7 +/- 0.79)% and (75.3 +/- 0.98)%, respectively]. While the rest of the alkaloids did not show any significant inhibition against AChE, three of the alkaloids, namely retamine, sparteine, and yohimbine, exerted a noteworthy anti-BChE effect as compared to galanthamine, the reference drug. 相似文献
132.
Ercan Ozdemir Ayse Demirkazik Ahmet Sevki Taskran Gokhan Arslan 《Bioelectromagnetics》2019,40(5):319-330
Much evidence demonstrates the antinociceptive effect of magnetic fields (MFs). However, the analgesic action mechanism of the electromagnetic field (EMF) is not exactly understood. The aim of the present study was to investigate the effects of 5‐HT1 and 5‐HT2 receptor agonists (serotonin HCl and 2,5‐dimethoxy‐4‐iodoamphetamine [DOI] hydrochloride) on EMF‐induced analgesia. In total, 66 adult male Wistar albino rats with an average body mass of 225 ± 13 g were used in this study. The animals were subjected to repeated exposures of alternating 50 Hz and 5 mT EMF for 2 h a day for 15 days. Prior to analgesia tests, serotonin HCl (5‐HT1 agonist) 4 mg/kg, WAY 100635 (5‐HT1 antagonist) 0.04 mg/kg, DOI hydrochloride (5‐HT2 receptor agonist) 4 mg/kg, and SB 204741 (5‐HT2 antagonist) 0.5 mg/kg doses were injected into rats. For statistical analysis of the data, analysis of variance was used and multiple comparisons were determined by Tukey’s test. Administration of serotonin HCl MF (5 mT)‐exposed rats produced a significant increase in percent maximal possible effect (% MPE) as compared with EMF group (P < 0.05). On the contrary, injection of WAY 100635 to MF‐exposed rats produced a significant decrease in analgesic activity (P < 0.05). Similarly, the administration of DOI hydrochloride significantly increased % MPE values as compared with the EMF group while SB 204741 reduced it (P < 0.05). In conclusion, our results suggested that serotonin 5‐HT1 and 5‐HT2 receptors play an important role in EMF‐induced analgesia; however, further research studies are necessary to understand the mechanism. Bioelectromagnetics. 2019;40:319–330. © 2019 Bioelectromagnetics Society. 相似文献
133.
The main objectives of this study were to optimize β-mannanase fermentation conditions by using Response Surface Methodology (RSM) and to model kinetically using the kinetic models. Based on the results, the optimum fermentation conditions were found to be initial sugar concentration of 10°Bx, whey concentration of 0.75% [w/v], and inoculum size of 8% (v/v). Under optimized conditions, β-mannanase activity (P), sugar consumed (ΔS), maximum β-mannanase production rate (QP), and sugar utilization yield (SUY) were 687.89 U/mL, 47.38 g/L, 118.54 U mL–1 day–1, and 69.73%, respectively. Kinetic models were employed to describe the optimum β-mannanase fermentation process. The kinetic analysis of β-mannanase fermentation showed that β-mannanase fermentation is growth associated because the α value (U/mgX) is approximately 330-fold higher than the β value (U/mgX·hr). Nevertheless, maintenance value (Z) was lower than γ value, thus showing that Aspergillus niger mainly utilizes the sugars for β-mannanase production and fungal growth. Consequently, carob extract and whey powder could be used to be cost-effective carbon and organic nitrogen sources, respectively. It was clearly indicated that the suggested kinetic models can successfully describe the fungal growth, β-mannanase production, and substrate consumption. 相似文献
134.
Athar Ata Chad D. Iverson Kosmulalage S. Kalhari Sarfraz Akhter Jordan Betteridge Mohammad Hadi Meshkatalsadat Ilkay Orhan Bilge Sener 《Phytochemistry》2010,71(14-15):1780-1786
From the aerial parts of Buxus hyrcana, three triterpenoidal alkaloids, 17-oxo-3-benzoylbuxadine (1), buxhyrcamine (2), and 31-demethylcyclobuxoviridine (3), along with 16 known compounds, cyclobuxoviridine (4), Nb-dimethylcyclobuxoviricine (5), E-buxenone (6), Z-buxenone (7), moenjodaramine (8), homomoenjodarmine (9), buxamine A (10), buxamine B (11), 31-hydroxybuxamine B (12), N20-formylbuxaminol E (13), papillozine C (14), buxmicrophylline F (15), buxrugulosamine (16), cyclobuxophylline O (17), spirofornabuxine (18) and arbora-1,9(11)-dien-3-one (19) were isolated. Their structures were elucidated by using NMR spectroscopic methods. All of the compounds exhibited moderate to weak acetylcholinesterase, butyrylcholinesterase and glutathione S-transferase inhibitory activities. Compounds 1–19 also exhibited modest anti-fungal activities against Candida albicans. Compounds 1, 2, 8, 9 and 18 also exhibited weak anti-leishmanial activity. 相似文献
135.
The design of microarrays is currently based on studies focusing on DNA hybridization reaction in bulk solution. However, the presence of a surface to which the probe strand is attached can make the solution‐based approximations invalid, resulting in sub‐optimum hybridization conditions. To determine the effect of surfaces on DNA duplex formation, the authors studied the dependence of DNA melting temperature (Tm) on target concentration. An automated system was developed to capture the melting profiles of a 25‐mer perfect‐match probe–target pair initially hybridized at 23°C. Target concentrations ranged from 0.0165 to 15 nM with different probe amounts (0.03–0.82 pmol on a surface area of 1018 Å2), a constant probe density (5 × 1012 molecules/cm2) and spacer length (15 dT). The authors found that Tm for duplexes anchored to a surface is lower than in‐solution, and this difference increases with increasing target concentration. In a representative set, a target concentration increase from 0.5 to 15 nM with 0.82 pmol of probe on the surface resulted in a Tm decrease of 6°C when compared with a 4°C increase in solution. At very low target concentrations, a multi‐melting process was observed in low temperature domains of the curves. This was attributed to the presence of truncated or mismatch probes. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012 相似文献
136.
137.
Ercan Soydan Ahmet Güler Selim Bıyık Murat Şentürk Deniz Ekinci 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):47-50
Carbonic anhydrase (CA) enzymes have been shown to play an important role in ion transport and in pH regulation in several organisms. Despite this information and the wealth of knowledge regarding the significance of CA enzymes, few studies have been reported about bee CA enzymes and the hazardous effects of chemicals. Using Apis mellifera as a model, this study aimed to determine the risk of pesticides on Apis mellifera Carbonic anhydrase enzyme (Am CA). CA was initially purified from Apis mellifera spermatheca for the first time in the literature. The enzyme was purified with an overall purification of ~35-fold with a molecular weight of ~32?kDa. The enzyme was then exposed to pesticides, including tebuconazole, propoxur, carbaryl, carbofuran, simazine and atrazine. The six pesticides dose-dependently inhibited in vitro AmCA activity at low micromolar concentrations. IC50 values for the pesticides were 0.0030, 0.0321, 0.0031, 0.0087, 0.0273 and 0.0165?μM, respectively. The AmCA inhibition mechanism of these compounds is unknown at this moment. 相似文献
138.
Oguz Tuncer Erdal Peker Nihat Demir Sinan Akbayram Ercan Kirimi 《The Journal of membrane biology》2013,246(7):525-528
We compared spectrophotometric analysis of the umbilical cords of infants with meconium aspiration syndrome (MAS) or with meconium-stained amniotic fluid (MSAF) and healthy infants. In a prospective study, 15 infants with MAS and 37 infants with MSAF were enrolled. Twenty healthy infants formed a control group. The absorption peak of umbilical cords with meconium was significantly higher in the infants with MAS or MSAF than in controls. Spectrophotometric analysis of the umbilical cords with meconium may be useful to identify developed neonates with MAS or MSAF. 相似文献
139.
Ketcham C Wang F Fisher SZ Ercan A van der Wel H Locke RD Sirajud-Doulah K Matta KL West CM 《The Journal of biological chemistry》2004,279(28):29050-29059
Skp1 is an adaptor-like protein in E3(SCF)-ubiquitin ligases and other multiprotein complexes of the cytoplasm and nucleus. In Dictyostelium, Skp1 is modified by an unusual pentasaccharide containing a Galalpha1-Fuc linkage, whose formation is examined here. A cytosolic extract from Dictyostelium was found to yield, after 2400-fold purification, an activity that could transfer Gal from UDP-Gal to both a Fuc-terminated glycoform of Skp1 and synthetic Fuc conjugates in the presence of Mn(2+) and dithiothreitol. The microsomal fraction was devoid of activity. The linkage formed was Galalpha1,3Fuc based on co-chromatography with only this synthetic isomer conjugate, and sensitivity to alpha1,3/6-galactosidase. Skp1 exhibited an almost 1000-fold lower K(m) and 35-fold higher V(max) compared with a simple alpha-fucoside, but this advantage was abolished by denaturation or alkylation of Cys residues. A comparison of a complete series of synthetic glycosides representing the non-reducing terminal mono-, di-, and trisaccharides of Skp1 revealed, surprisingly, that the disaccharide is most active owing primarily to a V(max) advantage, but still much less active than Skp1 itself because of a K(m) difference. These findings indicate that alpha-GalT1 is a cytoplasmic enzyme whose modification of Skp1 requires proper presentation of the terminal acceptor disaccharide by a folded Skp1 polypeptide, which correlates with previous evidence that the Galalpha1,3Fuc linkage is deficient in expressed mutant Skp1 proteins. 相似文献
140.
D Konukoglu M Ercan M Ayaz S Onen 《Journal of trace elements in medicine and biology》2001,15(2-3):119-122
The objective of the study was to investigate the effect of moderate glomerular dysfunction on oxidative stress. We determined the plasma and erythrocyte malondialdehyde (MDA) levels, as a marker of lipid peroxidation, erythrocyte glutathione (GSH) levels and activities of GSH-Px, GSH Red and SOD as an antioxidant enzymes, and plasma trace element levels containing Fe, Cu and Zn in twenty proteinuric patients (6.8 +/- 5.1 g/day) with moderate glomerular function and in 20 anemic control subjects. We found that the erythrocyte and plasma MDA levels and erythrocyte GSH-Px activities were significantly higher (p < 0.001, p < 0.001, p < 0.001, respectively) and the erythrocyte GSH levels and activities of GSH-Red and SOD activities were significantly lower (p < 0.001, p < 0.001, p < 0.001, respectively) in the patients than in the anemic subjects. Plasma Fe and Zn levels were not to be found significantly different in the patients compared to the anemic subjects. But plasma Cu levels were significantly higher in the patients (p < 0.05) when compared with the levels of anemic subjects. This study was concluded that cellular antioxidant activity decreases in proteinuric patients with moderate glomerular function. This may increase lipid peroxidation reactions by causing oxidative stress in erythrocyte membranes. 相似文献