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91.
Endometrial cancer (EC) is one of the most common types of gynecologic cancer of the female genital tract; it considered being the fourth leading death factor among other types of cancer. Therefore, developing new anti-cancer agents are crucial for cancer treatment. Based on the potential of Schiff based complexes for the induction of apoptosis, Schiff base compounds, and their metal complexes displayed excellent anticancer properties. In this current study, antiproliferative activity of [L(BF2)2] as a novel binuclear boron-fluoride complex was examined to preliminary research in eight different cell lines, HELA, DU-145, PC3, DLD-1, ECC-1, PNT1-A, HT-29, and MCF-7, it was found to have a potent, suppressive effect on human endometrial adenocarcinoma cell line ECC-1. Based on this data, later investigated its apoptotic, cytotoxic, and genotoxic properties on human endometrial adenocarcinoma cell line ECC-1 in different concentrations. Apoptotic and cytotoxic tests such as single cell gel electrophoresis assay (comet assay), DNA fragmentation laddering, acridine orange test for DNA damage, and ELISA for apoptotic measurement was performed. We also gauged the oxidative status by evaluating total antioxidant status (TAS) and total oxidant status (TOS). Oxidative stress index (OSI) was calculated too. As a result [L(BF2)2] has been found to have a marvelous effect on ECC-1 cells, especially in damaging their DNA and cause a series of reactions lead to apoptosis. Taken together, it suggests that the [L(BF2)2] complex can induce the apoptotic pathway of endometrial cancer cells and is a possible candidate for future cancer treatment studies.  相似文献   
92.
The study was conducted to assess whether selenium (Se) application modulates fertility to alter grain yield in bread wheat grown under different moisture regimes. Seeds of wheat cultivar Millat-2011 were sown in the plots using a randomized complete block design with three replicates per treatment. After germination, the plants were exposed to six moisture regimes, viz. no irrigation after germination, irrigation at boot stage, irrigations at boot and grain-filling stages, irrigations at crown root, boot and grain-filling stages, irrigations at crown root, boot, heading and grain-filling stages and irrigations at crown root, stem elongation, boot, heading and grain-filling stages. At the heading stage, foliar spray of sodium selenate (0, 2 and 4 mg Se L?1) was done. Withholding water at early growth stages significantly increased oxidative stress and decreased growth and grain yield. Irrespective of moisture regimes, foliar application of Se (2 mg L?1) decreased oxidative stress, modulated photosynthetic pigments and fertility and increased grain yield in wheat. The Se-mediated increase in grain yield was attributed to the increase in chlorophyll and ascorbic acid contents and fertility coupled with decrease of oxidative stress under different moisture regimes. The results could be helpful to manage wheat production in the semi-arid environments.  相似文献   
93.
In Turkey, the western thrips Frankliniella occidentalis (Pergande) is a key pest affecting eggplants grown in greenhouses for which an appropriate control strategy is under investigation. It was observed in a previous study that the release of the beneficial predatory mite Amblyseius swirskii (Athias‐Henriot) alone did not result in an effective control of thrips on eggplants. Since pollen is known to improve control efficiency of predators, this study was undertaken to investigate if provision of pollen to eggplants can greatly improve the efficiency of A. swirskii in controlling thrips. The experiments were carried out in both greenhouse and low tunnel. The provision of pollen led to a significant increase in the predator population density on the eggplants but did not result in an effective control of the thrips populations. In this paper, various factors are discussed that could have affected the efficiency of the predatory mite in controlling F. occidentalis on eggplants.  相似文献   
94.
Nitrate reductase activity (NRA) in different compartments of 14 Mediterranean geophytes (bulbous, tuberous and rhizomatous) and actual mineral nitrogen (NO3 and NH4+) in their soils were investigated. The nitrate reduction capacities of each species were determined as NRA per total plant material. Differences among compartments for NRA were significant in all species. The highest NRA was found in leaves of tuberous species (Anemone coronaria, Cyclamen coum) and of most bulbous species (Allium flavum, Allium guttatum, Bellevelia sarmatica, Galanthus plicatus, Leucojum aestivum, Ornithogalum nutans, Tulipa sylvestris). Therefore, in this group of species the contribution of the leaves to total plant NRA was the highest. The other bulbous species (Allium scorodoprasum, Crocus chrysanthus, Fritillaria bithynica, Muscari neglectum) and one rhizomatous taxon (Iris suaveolens) have a different NRA distribution within the plants. In these species the highest values of NRA were found in different organs. For example, in Allium scorodoprasum the highest NRA was in tunics, and in flowers in M. neglectum. Although leaves are the main compartments reducing nitrate in most of the studied geophytes, other compartments also contribute to total plant nitrate reduction.Our results show that the nitrate reduction capacity is different among geophyte species. Even if it roughly reflects the nitrogen supply in a habitat, differences in nitrate reduction capacities of different species collected from same sites indicate that the nitrate reducing capacity is species-specific.  相似文献   
95.
96.
The molecular geometries, normal mode frequencies, intensities and corresponding infrared assignments of monomeric and dimeric 2,3-dimethylpyridine, 2,4-dimethylpyridine, 3,4-dimethylpyridine, 3,5-dimethylpyridine and monomeric 2,6-dimethylpyridine in the ground state were investigated at the density functional theory (DFT)-B3LYP level using the 6-311+G(d, p) basis set. The vibrational frequencies and geometric parameters of C–H stretching and bending in the fundamental region were calculated and compared to the Fourier transform infrared (FT-IR) data obtained. In the studied monomeric and dimeric dimethyl substituted pyridine derivatives, the C–H stretching and bending frequency shifts that occur between the dimer and the monomer may be diagnostic of the magnitude of dimerization energy. As supported by data in the literature, the most stable dimeric form was obtained for the 3,4-dimethylpyridine molecule. Figure Molecular model and numbering scheme of the studied dimeric dimethylpyridinederivatives  相似文献   
97.
98.
Adipokines and ghrelin play role in insulin resistance, the key pathophysiological abnormality in patients with nonalcoholic fatty liver diseases. In the present study, relationship between nonalcoholic steatohepatitis (NASH) and serum adipokine and ghrelin levels was investigated. Thirty seven patients with biopsy-proven NASH and 25 age- and sex-matched controls were enrolled. Ten of NASH patients (27%) had diabetes mellitus (n = 5) or impaired glucose tolerance (n = 5). Body mass index (BMI) was less than 30 kg/m(2) in 67.6% of patients, while in the remaining 32.4% it was more than 30 kg/m(2). Serum adiponectin, leptin, TNF-alpha, and ghrelin were determined. Serum leptin (15.49 +/- 4.84 vs 10.31 +/- 2.53) and TNF-alpha (12.1 +/- 2.7 vs 10.31 +/- 2.56) levels were significantly higher in the NASH group compared to in the control group (P < .001 for each). Nevertheless, adiponectin (11.1 +/- 2.1 vs 17.3 +/- 2.8) and ghrelin (6.46 +/- 1.1 vs 7.8 +/- 1.1) levels were lower in the NASH group than in the control group (P < .001 for each). Serum levels of the adipokines and ghrelin, however, were comparable in the subgroups of patients regardless of whether BMI was < 30 or > 30 or glucose tolerance was impaired or not (P > .05). Additionally, neither adipokines nor ghrelin was correlated with histopathological grade and stage (P > .05). In conclusion; there is a significant relationship between NASH and adipokines and ghrelin independent from BMI and status of the glucose metabolism. These cytokines that appear to have role in the pathogenesis of NASH, however, do not have any effect upon the severity of the histopathology.  相似文献   
99.
Kucukkaya B  Arslan DO  Kan B 《Life sciences》2006,78(11):1217-1224
Heterotrimeric G proteins which couple extracellular signals to intracellular effectors play a central role in cell growth and differentiation. The pluripotent erythroleukemic cell line K562 that acquires the capability to synthesize hemoglobin in response to a variety of agents can be used as a model system for erythroid differentiation. Using Western blot analysis and RT-PCR, we studied alterations in G protein expression accompanying hemin-induced differentiation of K562 cells. We demonstrated the presence of G(alpha s), G(alpha i2) and G(alpha q) and the absence of G(alpha i1), G(alpha o) and G(alpha 16) in K562 cells. We observed the short form of G(alpha s) to be expressed predominantly in these cells. Treatment of K562 cells with hemin resulted in an increase in the levels of G(alpha s) and G(alpha q). On the other hand, the level of G(alpha i2) was found to increase on the third day after induction with hemin, followed by a decrease to levels lower of those of uninduced cells. The mitogen-activated protein kinase ERK1/2 pathway is crucial in the control of cell proliferation and differentiation. Both Gi- and Gq-coupled receptors stimulate MAPK activation. We therefore examined the phosphorylation of ERK1/2 during hemin-induced differentiation of K562 cells. Using anti-ERK1/2 antibodies, we observed that ERK2 was primarily phosphorylated in K562 cells. ERK2 phosphorylation increased gradually until 48 h and returned to basal values by 96 h following hemin treatment. Our results suggest that changes in G protein expression and ERK2 activity are involved in hemin-induced differentiation of K562 cells.  相似文献   
100.
Human ESC-derived mesenchymal stem cell (MSC)-conditioned medium (CM) was previously shown to mediate cardioprotection during myocardial ischemia/reperfusion injury through large complexes of 50–100 nm. Here we show that these MSCs secreted 50- to 100-nm particles. These particles could be visualized by electron microscopy and were shown to be phospholipid vesicles consisting of cholesterol, sphingomyelin, and phosphatidylcholine. They contained coimmunoprecipitating exosome-associated proteins, e.g., CD81, CD9, and Alix. These particles were purified as a homogeneous population of particles with a hydrodynamic radius of 55–65 nm by size-exclusion fractionation on a HPLC. Together these observations indicated that these particles are exosomes. These purified exosomes reduced infarct size in a mouse model of myocardial ischemia/reperfusion injury. Therefore, MSC mediated its cardioprotective paracrine effect by secreting exosomes. This novel role of exosomes highlights a new perspective into intercellular mediation of tissue injury and repair, and engenders novel approaches to the development of biologics for tissue repair.  相似文献   
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