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Thirty-one 4-oxoquinoline-3-carboxamides derivatives were synthesized and evaluated for their anti-fibrotic activities by the inhibition of TGF-β1-induced total collagen accumulation and anti-inflammatory activities by the inhibition of LPS-stimulated TNF-α production. Among them, three compounds (10a, 10l and 11g) exhibited potent inhibitory effects on both TGF-β1-induced total collagen accumulation and LPS-stimulated TNF-α production. Furthermore, oral administrations of 10l at a dose of 20 mg/kg/day for 4 weeks effectively alleviated lung inflammation and injury, and decreased lung collagen accumulation in bleomycin-induced pulmonary fibrosis model. Histopathological evaluation of lung tissue confirmed 10l as a potential, orally active agent for the treatment of pulmonary fibrosis.  相似文献   
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《Process Biochemistry》2007,42(9):1291-1295
Ellagic acid production from cups extract of valonia acorns by pure and mixed cultures of Aspergillus oryzae and Trichoderma reesei was investigated. Ellagitannin acyl hydrolase and xylanase as well as cellulase during the pure and mixed cultures were also determined. The results revealed that mixed culture could produce higher ellagic acid yield (23%) than either of pure culture. And it was found that the three enzymes from mixed culture appeared synergistic effect on ellagic acid production. Statistical analysis showed that ellagic acid yield was correlated very well with the three enzymes activities, resulting in the model for ellagic acid production with high R2 value of 0.998 and significant level p < 0.004.  相似文献   
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Topors is a DNA topoisomerase I- and p53-binding protein, and mainly functions as a p53 regulator. Accumulating evidence also supports the notion that Topors plays the role as a negative regulator of cell growth, and possibly as a tumor suppressor. Here, we demonstrated that Topors is also involved in normal mitotic progression, since Topors depletion delays mitotic entry and affects mitotic progression. Furthermore, Topors is degradated in response to the activation of the spindle checkpoint. Significantly, Polo-like kinase 1 (Plk1)-associated phosphorylation of Topors at S718 is essential for nocodazole-induced degradation of Topors.  相似文献   
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《Process Biochemistry》2010,45(9):1477-1485
A 48 kDa, chitin-binding lectin with antifungal, antiviral and apoptosis-inducing activities was isolated from the rhizomes of Setcreasea purpurea Boom, a member of family Commelinaceae. Setcreasea purpurea lectin (designated as SPL) is a homotetrameric protein consisting of 12031.9 Da subunits linked by non-covalent bonds as determined by SDS-PAGE, gel filtration and MS. The N-terminal 25 amino-acid sequence of SPL, NVLGRDAYCGSQNPGATCPGLCCSK was determined and homology analysis suggested that SPL belongs to the family of chitin-binding plant lectins composed of hevein domains. The lectin exhibited strong hemagglutinating activity towards rabbit erythrocytes at 0.95 μg/ml and the activity could be reversed exclusively by chitin hydrolysate (oligomers of GlcNAc). Its hemagglutinating activity was stable in pH range of 2.0–9.0 and it showed excellent thermal tolerance. SPL showed antifungal activity against Rhizoctonia solani, Sclerotinia sclerotiorum, Penicillium italicum and Helminthosporiun maydis. It also exhibited inhibitory effect on HIV-1 (IIIB) and HIV-2 (ROD), with an EC50 of 13.8 ± 1.3 and 57.1 ± 15 μg/ml, respectively. Subsequently, MTT method, cell morphological analysis and LDH activity-based cytotoxicity assays demonstrated that SPL was highly cytotoxic to CNE-1 cells and induced apoptosis in a dose-dependent manner. Moreover, due to the caspase inhibitors analyses, caspase was also found to play an important role in the potential apoptotic mechanism of SPL.  相似文献   
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为明确昆虫抗冻蛋白基因转入甘薯(Ipomoea batatas)后是否能提升其抗冻能力,进而为培育甘薯抗冻育种材料奠定基础,将黄粉虫(Tenebrio molitor)抗冻蛋白基因TmAFP导入植物基因表达质粒,经农杆菌介导的遗传转化获得抗冻甘薯新材料。以甘薯品种Huachano为受体材料建立甘薯植株高效再生体系,并采用不同成分的体细胞胚成熟培养基培养胚性悬浮细胞。胚性愈伤组织对除草剂的敏感性测试结果表明,转基因阳性植株筛选的最适培养基为MS+0.2 mg·L–12,4-D+0.8 mg·L^–1 GAP+100 mg·L^–1 Carb。将表达质粒分别转化Huachano后共获得7个胚性愈伤团并最终获得42株再生抗性植株,其中转pSUIBEV3-AFP有23个株系,转pCAMBIA-AFP有19个株系,经PCR、Southern杂交和RT-PCR检测后证实TmAFP基因已整合至甘薯基因组中并获得表达。将转基因甘薯及对照植株在–1℃下处理15小时后转移至室温,结果表明,转基因甘薯植株的抗冻能力显著提升。  相似文献   
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