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Iryna A. Koval Mieke Huisman Eric Saint-Aman Bernt Krebs 《Inorganica chimica acta》2006,359(12):4071-4078
The new asymmetric phenol-based N,O,S-ligand Hpy2th1as was prepared by the straightforward reductive amination of 3-{[bis(pyridin-2-ylmethyl)amino]methyl}-2-hydroxybenzaldehyde with (thiophen-2-yl)methylamine. This potentially hexadentate ligand was used to coordinate to copper(II) chloride. Two dinuclear copper complexes were thus synthesised and fully characterized. Although the two coordination compounds exhibit identical complex cations, the crystal packings of both molecules significantly differ, which is most likely induced by the distinct, but geometrically related anions, namely tetrachlorocuprate(II) and perchlorate. 相似文献
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Coussens G Aesaert S Verelst W Demeulenaere M De Buck S Njuguna E Inzé D Van Lijsebettens M 《Journal of experimental botany》2012,63(11):4263-4273
The biotechnological approach to improve performance or yield of crops or for engineering metabolic pathways requires the expression of a number of transgenes, each with a specific promoter to avoid induction of silencing mechanisms. In maize (Zea mays), used as a model for cereals, an efficient Agrobacterium tumefaciens-mediated transformation system has been established that is applied for translational research. In the current transformation vectors, the promoters of the 35S gene of the cauliflower mosaic virus and of the ubiquitin gene of maize are often used to drive the bialaphos-selectable marker and the transgene, respectively. To expand the number of promoters, genes with either constitutive or seed-specific expression were selected in Brachypodium distachyon, a model grass distantly related to maize. After the corresponding Brachypodium promoters had been fused to the β-glucuronidase reporter gene, their activity was followed throughout maize development and quantified in a fluorimetric assay with the 4-methylumbelliferyl β-D-glucuronide substrate. The promoters pBdEF1α and pBdUBI10 were constitutively and highly active in maize, whereas pBdGLU1 was clearly endosperm-specific, hence, expanding the toolbox for transgene analysis in maize. The data indicate that Brachypodium is an excellent resource for promoters for transgenic research in heterologous cereal species. 相似文献
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Meurs I Calpe-Berdiel L Habets KL Zhao Y Korporaal SJ Mommaas AM Josselin E Hildebrand RB Ye D Out R Kuiper J Van Berkel TJ Chimini G Van Eck M 《PloS one》2012,7(3):e30984
ABCA7, a close relative of ABCA1 which facilitates cholesterol efflux to lipid-poor apoproteins, has been implicated in macrophage lipid efflux and clearance of apoptotic cells in in vitro studies. In the current study, we investigated the in vivo effects of macrophage ABCA7 deficiency on lipid metabolism and atherosclerosis. Chimeras with dysfunctional ABCA7 in macrophages and other blood cells were generated by transplantation of bone marrow from ABCA7 knockout (KO) mice into irradiated low-density lipoprotein receptor (LDLr) KO mice. Unexpectedly, macrophage ABCA7 deficiency did not significantly affect atherosclerosis susceptibility of LDLr KO mice after 10 weeks Western-type diet feeding. However, ABCA7 deficiency was associated with 2-fold (p<0.05) higher macrophage ABCA1 mRNA expression levels. Combined disruption of ABCA1 and ABCA7 in bone-marrow-derived cells increased atherosclerotic lesion development (1.5-fold (p>0.05) as compared to wild type transplanted mice. However, single deletion of ABCA1 had a similar effect (1.8-fold, p<0.05). Macrophage foam cell accumulation in the peritoneal cavity was reduced in ABCA1/ABCA7 dKO transplanted animals as compared to single ABCA1 KO transplanted mice, which was associated with increased ABCG1 expression. Interestingly, spleens of ABCA1/ABCA7 double KO transplanted mice were significantly larger as compared to the other 3 groups and showed massive macrophage lipid accumulation, a reduction in CD3+ T-cells, and increased expression of key regulators of erythropoiesis. In conclusion, deletion of ABCA7 in bone marrow-derived cells does not affect atherogenesis in the arterial wall neither in the absence or presence of ABCA1. Interestingly, combined deletion of bone marrow ABCA1 and ABCA7 causes severe splenomegaly associated with cellular lipid accumulation, a reduction in splenic CD3+ T cells, and induced markers of erythropoeisis. Our data indicate that ABCA7 may play a role in T cell proliferation and erythropoeisis in spleen. 相似文献
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Bongartz JP Buntinx M Coesemans E Hermans B Lommen GV Wauwe JV 《Bioorganic & medicinal chemistry letters》2008,18(21):5819-5823
The synthesis and evaluation of benzetimide derivatives showing potent CXCR3 antagonism are described. Optimization of the screening hits led to the identification of more potent CXCR3 antagonists devoid of anti-cholinergic activity and identification of the key pharmacophore moieties of the series. 相似文献