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291.
Sevim Karakas Celik Zehra Safi Öz Ahmet Dursun Aysun Unal Ufuk Emre Salih Cicek Fatih Mehmet Keni 《Molecular biology reports》2014,41(3):1653-1658
Proinflammatory cytokines with immunosuppressive properties play an important role in the pathogenesis of multiple sclerosis (MS). Interleukin 18 (IL-18) is one of the most important innate cytokines produced from macrophages in the early stages of the inflammatory immune response. The purpose of this study was to determine whether there was any relationship between IL18 gene polymorphisms and MS. IL18 genotyping were performed in 101 MS patients and 164 control subjects by using the PCR–restriction fragment length polymorphism (PCR–RFLP) method. The frequency of MS patients with the CC genotype of the IL18 gene at position ?137 was significantly higher than with the GG genotype [p = 0.01, odds ratio (OR) 3.17]. In haplotype analysis of two SNPs in the IL18 gene, frequency of the CC haplotype was significantly higher in MS patients (p = 0.002, OR 3.0). However, the genotype distribution of the IL18 ?607 C/A polymorphism in the MS patient group was not significantly different from that of the control group. These data suggest that IL18 gene polymorphisms at position ?137 might be a genetic risk factor for MS in the Turkish population. 相似文献
292.
Birsen Elibol‐Can Ilknur Dursun Ilknur Telkes Ertugrul Kilic Sinan Canan Ewa Jakubowska‐Dogru 《Developmental neurobiology》2014,74(5):498-513
Ethanol is known as a potent teratogen having adverse effects on brain and behavior. However, some of the behavioral deficits caused by fetal alcohol exposure and well expressed in juveniles ameliorate with maturation may suggest some kind of functional recovery occurring during postnatal development. The aim of this study was to reexamine age‐dependent behavioral impairments in fetal‐alcohol rats and to investigate the changes in neurogenesis and gross morphology of the hippocampus during a protracted postnatal period searching for developmental deficits and/or delays that would correlate with behavioral impairments in juveniles and for potential compensatory processes responsible for their amelioration in adults. Ethanol was delivered to the pregnant dams by intragastric intubation throughout 7–21 gestation days at daily dose of 6 g/kg. Isocaloric intubation and intact control groups were included. Locomotor activity, anxiety, and spatial learning tasks were applied to juvenile and young‐adult rats from all groups. Unbiased stereological estimates of hippocampal volumes, the total number of pyramidal and granular cells, and double cortin expressing neurons were carried out for postnatal days (PDs) PD1, PD10, PD30, and PD60. Alcohol insult during second trimester equivalent caused significant deficits in the spatial learning in juvenile rats; however, its effect on hippocampal morphology was limited to a marginally lower number of granular cells in dentate gyrus (DG) on PD30. Thus, initial behavioral deficits and the following functional recovery in fetal‐alcohol subjects may be due to more subtle plastic changes within the hippocampal formation but also in other structures of the extended hippocampal circuit. Further investigation is required. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 74: 498–513, 2014 相似文献
293.
Bektaşoğlu B Esin Celik S Ozyürek M Güçlü K Apak R 《Biochemical and biophysical research communications》2006,345(3):1194-1200
Reactive oxygen species (ROS) such as superoxide anion, hydroxyl ((*)OH), peroxyl, and alkoxyl radicals may attack biological macromolecules giving rise to oxidative stress-originated diseases. Since (*)OH is very short-lived, secondary products resulting from (*)OH attack to various probes are measured. Although the measurement of aromatic hydroxylation with HPLC/electrochemical detection is more specific than the low-yield TBARS test, it requires sophisticated instrumentation. As a more convenient and less costly alternative, we used p-aminobenzoate, 2,4- and 3,5-dimethoxybenzoate probes for detecting hydroxyl radicals generated from an equivalent mixture of Fe(II)+EDTA with hydrogen peroxide. The produced hydroxyl radicals attacked both the probe and the water-soluble antioxidants in 37 degrees C-incubated solutions for 2h. The CUPRAC (i.e., our original method for total antioxidant capacity assay) absorbance of the ethylacetate extract due to the reduction of Cu(II)-neocuproine reagent by the hydroxylated probe decreased in the presence of (*)OH scavengers, the difference being proportional to the scavenging ability of the tested compound. A rate constant for the reaction of the scavenger with hydroxyl radical can be deduced from the inhibition of color formation. The second-order rate constants of the scavengers were determined with competition kinetics by means of a linear plot of A(0)/A as a function of C(scavenger)/C(probe), where A(0) and A are the CUPRAC absorbances of the system in the absence and presence of scavenger, respectively, and C is the molar concentration of relevant species. The 2,4- and 3,5-dimethoxybenzoates were the best probes in terms of linearity and sensitivity. Iodide, metabisulfite, hexacyanoferrate(II), thiourea, formate, and dimethyl sulfoxide were shown by the modified CUPRAC assay to be more effective scavengers than mannitol, glucose, lysine, and simple alcohols, as in the TBARS assay. The developed method is less lengthy, more specific, and of a higher yield than the classical TBARS assay. The hydroxyl radical scavenging rate constants of ascorbic acid, formate, and hexacyanoferrate(II) that caused interference in other assays could be easily found with the proposed procedure. 相似文献
294.
Sharing is caring? Measurement error and the issues arising from combining 3D morphometric datasets
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Carmelo Fruciano Mélina A. Celik Kaylene Butler Tom Dooley Vera Weisbecker Matthew J. Phillips 《Ecology and evolution》2017,7(17):7034-7046
Geometric morphometrics is routinely used in ecology and evolution and morphometric datasets are increasingly shared among researchers, allowing for more comprehensive studies and higher statistical power (as a consequence of increased sample size). However, sharing of morphometric data opens up the question of how much nonbiologically relevant variation (i.e., measurement error) is introduced in the resulting datasets and how this variation affects analyses. We perform a set of analyses based on an empirical 3D geometric morphometric dataset. In particular, we quantify the amount of error associated with combining data from multiple devices and digitized by multiple operators and test for the presence of bias. We also extend these analyses to a dataset obtained with a recently developed automated method, which does not require human‐digitized landmarks. Further, we analyze how measurement error affects estimates of phylogenetic signal and how its effect compares with the effect of phylogenetic uncertainty. We show that measurement error can be substantial when combining surface models produced by different devices and even more among landmarks digitized by different operators. We also document the presence of small, but significant, amounts of nonrandom error (i.e., bias). Measurement error is heavily reduced by excluding landmarks that are difficult to digitize. The automated method we tested had low levels of error, if used in combination with a procedure for dimensionality reduction. Estimates of phylogenetic signal can be more affected by measurement error than by phylogenetic uncertainty. Our results generally highlight the importance of landmark choice and the usefulness of estimating measurement error. Further, measurement error may limit comparisons of estimates of phylogenetic signal across studies if these have been performed using different devices or by different operators. Finally, we also show how widely held assumptions do not always hold true, particularly that measurement error affects inference more at a shallower phylogenetic scale and that automated methods perform worse than human digitization. 相似文献
295.
Wu Susie R. Celik Ilke Apul Defne Chen Jiquan 《The International Journal of Life Cycle Assessment》2019,24(10):1898-1910
The International Journal of Life Cycle Assessment - The objective of this study was to develop a social impact quantification framework for the resource extraction industry. The framework was... 相似文献
296.
Mehmet Cengiz Baloglu Lutfiye Yildiz Ozer Buket Pirci Gokhan Zengin Abdullahi Ibrahim Uba Yasemin Celik Altunoglu 《化学与生物多样性》2023,20(10):e202300291
Liquidambar orientalis Mill., commonly called the Anatolian sweetgum or Sigla tree, is endemic to southwestern Turkey. It has been historically significant in traditional medicine. In our research, we delved into the therapeutic attributes of its oil, emphasizing its antioxidant, antimicrobial, and antitumor properties. The primary chemical constituent of the gum is styrene, accounting for 78.5 %. The gum demonstrated antioxidant capabilities in several assays, including in 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), cupric reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP). It displayed bactericidal actions against various gram-positive bacteria, such as Staphylococcus aureus, and gram-negative strains, including Escherichia coli. Additionally, the oil showcased potent antitumor effects against breast (MDA-MB-231), lung (A549), and prostate (PC3) cancer cell lines. These effects were found to be both time- and dose-dependent. L. orientalis Mill. oil showed the best antitumor activity against breast, lung, and prostate cancer cell lines after the 24 h and 48 h treatment. Its oil might induce autophagy in the PC3 prostate cancer cell line, whereas its cytotoxicity against MDA-MB-231 and A549 cancer cell lines might not be correlated with autophagy or apoptosis pathways. In conclusion, the oil from the Sigla tree offers promising therapeutic potential and warrants further exploration. 相似文献
297.
In this study, the local atomic rearrangements caused by thermally induced martensitic phase transitions in Ni-37.5 at.%Al alloy model based on embedded atom method are studied using molecular dynamics simulations. The local atomic orders and defective structural part of the transformed regions are analysed using the bond orientational order parameters, which are employed mainly to diagnose short-range order of liquid state structures, and the radial distribution functions. In addition, short-range order properties in the model alloy were analysed using Honeycutt–Andersen method, which is commonly used to determine the relationship between atomic pairs. The results of our simulations disclosed that the local atomic rearrangement is of great importance to understand the local character of the transformation path from austenite to martensite phase. 相似文献
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