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991.
Given the anti-inflammatory and protective role of probiotics in atherosclerosis and the regulatory role of micro RNA (miRNA) in endothelial cell (dys) functions, this study aimed to investigate the effect of Lactobacillus acidophilus (La) on cellular death and the expression of miRNA-21, 92a, 155, and 663 in human umbilical vein endothelial cell (HUVEC) induced by Escherichia coli lipopolysaccharide (Ec-LPS). LPS-treated and untreated HUVECs were cultured in the presence of different La conditions such as La-conditioned media (LaCM), La water extract (LaWE), La culture-filtered (LaFS) and unfiltered supernatants (LaUFS). After 24 h, apoptosis, necrosis and the levels of the mentioned miRNAs were measured using flow cytometry and real-time PCR methods, respectively. LaCM decreased apoptosis, necrosis and inflammatory miR-155 and conversely increased anti-apoptotic miR-21 in Ec-LPS-treated HUVECs. Association analysis revealed negative correlations between necrosis and the levels of miR-21, miR-92a, and miR-155. The beneficial effects of L. acidophilus on the ECs death and expression of atherosclerosis related miRNAs in these cells imply a new aspect of its regulation in cardiovascular diseases rather than previously described ones and suggest this probiotic bacterium as a candidate in the preventative therapy of atherosclerosis.  相似文献   
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IntroductionOsteoarthritis (OA) is the most common type of arthritis and proinflammatory cytokines have been considered as the main etiologic factor in the pathogenesis of the disease. Serum levels of cytokines, that are associated with innate immunity and TH1 cells, have been analyzed in OA patients, however, there is limited research that profiles cytokines associated with Th17 cells and their relation to vitamin D3 and pain.ResultsSerum levels of IL-17A, and IL-23 were statistically higher in OA patients than in healthy controls, while IL-21 and vitamin D3 were significantly lower in OA patients when compared to controls. A significant positive correlation was found between the serum levels of IL-17A and IL-23 using WOMAC pain scores and vitamin D3 serum levels.DiscussionThe results suggest that IL-17A plays a significant role in OA pathogenesis and the induction of pain. Decreased serum levels of vitamin D3 may reflect a positive role played by the factor in the regulation of immune responses in OA patients.  相似文献   
993.
Efficiency of tiametoxam was determined on population growth parameters of cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae) using demographic toxicology by leaf spray method. At first, bioassay was performed. The LC50 values and confidence limits for thiamethoxam were 169.05?ppm (92.61–342.51). To evaluate, the sub-lethal effect of this insecticide on population growth parameters of cabbage aphid, LC25 and LC10 concentrations of tiametoxam were used at 58.8 and 22.05?ppm, respectively. Also, the LC50 value of insecticide on the life table estimates was measured. Experiments were carried out in the laboratory at 23?±?1?°C, 60?±?5% RH and 16:8 (L:D) photoperiod on cabbage seedlings, Brassica oleracea, var. capitata L. Net fecundity rate decreased in insecticide-treated populations. Intrinsic rates of increase (rm) were lower in tiametoxam treatment than in controls. There was a relative increase in intrinsic death rates of treated populations. The mean generation time and doubling time were also lower in population treated with insecticide than the control. There was a considerable reduction in the average numbers of nymphs reproduced per female as compared with the control. The average longevity of female adults in the control was significantly different (p?<?0.05) from those treated with thiamethoxam.  相似文献   
994.
New carbo[6]helicene derivatives grafted with π‐conjugated cyano‐phenyl arms were synthesized in enantiopure forms and their π‐conjugation examined by UV–vis spectroscopy. The influence of the π‐conjugation on the circular dichroism spectra and molar rotations is discussed based on comparing experimental data with results from quantum‐chemical calculations. The results highlight the fact that increasing the spatial extension of the π‐system in a helicene molecule is an efficient way of increasing its molar rotation. Chirality 25:455–465, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
995.
Mehdi Dehghani 《Grana》2013,52(2):79-101
The pollen morphology of two Bienertia species and 28 Suaeda species from the Old World has been studied with light and scanning electron microscopy. Pollen morphological characters used in this study include pollen diameter, pore number, pore diameter, operculum diameter, chord distance, exine thickness, plus number and characteristics of exine spinules and operculum spinules. Using these characters, the pollen of Bienertia is clearly distinguished from that of Suaeda. In addition, pollen data support recent molecular studies which merge the genus Borszczowia into Suaeda. The pollen grains of Suaeda show notable variation; in some cases this allows morphological distinctions to be made between species. Taxonomically, pore number is observed to be a more useful character than pollen diameter. Principal components analysis (PCA) shows only a weak correlation between pollen characters and habit (life form), habitat, mode of photosynthesis or phylogenetic relationships. Interestingly, however, the annual C3 and C4 species of section Schoberia are usually characterised by a higher pore number than the perennial C4 species.  相似文献   
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997.
Chemoresistance is a complicated process developed by most cancers and accounts for the majority of relapse and metastasis in cancer. The main mechanisms of chemoresistance phenotype include increased expression and/or activated drug efflux pumps, altered DNA repair, altered metabolism of therapeutics as well as impaired apoptotic signaling pathways. Aberrant sphingolipid signaling has also recently received considerable attention in chemoresistance. Sphingolipid metabolites regulate main biological processes such as apoptosis, cell survival, proliferation, and differentiation. Two sphingosine kinases, SphK1 and SphK2, convert sphingosine to sphingosine-1-phosphate, an antiapoptotic bioactive lipid mediator. Numerous evidence has revealed the involvement of activated SphK1 in tumorigenesis and resistance, however, contradictory results have been found for the role of SphK2 in these functions. In some studies, overexpression of SphK2 suppressed cell growth and induced apoptosis. In contrast, some others have shown cell proliferation and tumor promotion effect for SphK2. Our understanding of the role of SphK2 in cancer does not have a sufficient integrity. The main focus of this review will be on the re-evaluation of the role of SphK2 in cell death and chemoresistance in light of our new understanding of molecular targeted therapy. We will also highlight the connections between SphK2 and the DNA damage response. Finally, we will provide our insight into the regulatory mechanisms of SphKs by two main categories, micro and long, noncoding RNAs as the novel players of cancer chemoresistance.  相似文献   
998.
Bioprocess and Biosystems Engineering - Waters contaminated with naphthenic acids (NAs) and associated tailings are one of the major environmental challenges associated with the processing of oil...  相似文献   
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