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51.
Due to their unique fluorescent properties, quantum dots present a great potential for biolabelling applications; however,
the toxic interactions of quantum dots with biopolymers are little known. The toxic interactions of glutathione-capped CdTe
quantum dots with trypsin were studied in this paper using synchronous fluorescence spectroscopy, fluorescence emission spectra,
and UV–vis absorption spectra. The interaction between CdTe quantum dots and trypsin resulted in structure changes of trypsin
and inhibited trypsin's activity. Fluorescence emission spectra revealed that the quenching mechanism of trypsin by CdTe quantum
dots was a static quenching process. The binding constant and the number of binding sites at 288 and 298 K were calculated
to be 1.98 × 106 L mol−1 and 1.37, and 6.43 × 104 L mol−1 and 1.09, respectively. Hydrogen bonds and van der Waals' forces played major roles in this process. 相似文献
52.
Yanxiao Feng Yuechuan Zhang Cuifeng Ying Deqiang Wang Chunlei Du 《基因组蛋白质组与生物信息学报(英文版)》2015,13(3):200-201
<正>The authors regret that there were typos in the online version of Figure 4 published in Issue 1,2015.In the figure legend boxes of panels F and G,‘‘Ni’’should be corrected to‘‘N’’for the labeling of the green curves.The figure in the printed version has been corrected.The correct Figure 4 is shown below.The authors would like to apologize for any inconvenience caused. 相似文献
53.
Meng Sun Jing Ren Hui Du Yanmin Zhang Jie Zhang Sicen Wang Langchong He 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(28):2712-2718
We have developed an online analytical method that combines A431 cell membrane chromatography (A431/CMC) with high performance liquid chromatography and mass spectrometry (LC/MS) for identifying active components from Radix Caulophylli acting on human EGFR. Retention fractions on A431/CMC model were captured onto an enrichment column and the components were directly analyzed by combining a 10-port column switcher with an LC/MS system for separation and preliminary identification. Using Sorafenib tosylate as a positive control, taspine and caulophine from Radix Caulophylli were identified as the active molecules which could act on the EGFR. This A431/CMC-online-LC/MS method can be applied for screening active components acting on EGFR from traditional Chinese medicines exemplified by Radix Caulophylli and will be of great utility in drug discovery using natural medicinal herbs as a source of novel compounds. 相似文献
54.
Zhijiang Yan Mathieu Delannoy Chen Ling Danielle Daee Fekret Osman Parameswary A. Muniandy Xi Shen Anneke B. Oostra Hansen Du Jurgen Steltenpool Ti Lin Beatrice Schuster Chantal Décaillet Andrzej Stasiak Alicja Z. Stasiak Stacie Stone Maureen E. Hoatlin Detlev Schindler Christopher L. Woodcock Hans Joenje Weidong Wang 《Molecular cell》2010,37(6):865-878
55.
Liu Q He X Liu Y Du B Wang X Zhang W Jia P Dong J Ma J Wang X Li S Zhang H 《Biochemical and biophysical research communications》2008,377(3):775-779
Oxidative damage is an important mechanism in X-ray-induced cell death. Radiolysis of water molecules is a source of reactive oxygen species (ROS) that contribute to X-ray-induced cell death. In this study, we showed by ROS detection and a cell survival assay that NADPH oxidase has a very important role in X-ray-induced cell death. Under X-ray irradiation, the upregulation of the expression of NADPH oxidase membrane subunit gp91phox was dose-dependent. Meanwhile, the cytoplasmic subunit p47phox was translocated to the cell membrane and localized with p22phox and gp91phox to form reactive NADPH oxidase. Our data suggest, for the first time, that NADPH oxidase-mediated generation of ROS is an important contributor to X-ray-induced cell death. This suggests a new target for combined gene transfer and radiotherapy. 相似文献
56.
pH-responsive nanoparticles (NPs) are currently under intense development as drug delivery systems for cancer therapy. Among various pH-responsiveness, NPs that are designed to target slightly acidic extracellular pH environment (pHe) of solid tumors provide a new paradigm of tumor targeted drug delivery. Compared to conventional specific surface targeting approaches, the pHe-targeting strategy is considered to be more general due to the common occurrence of acidic microenvironment in solid tumors. This review mainly focuses on the design and applications of pHe-activated NPs, with special emphasis on pHe-activated surface charge reversal NPs, for drug and siRNA delivery to tumors. The novel development of NPs described here offers great potential for achieving better therapeutic effects in cancer treatment. 相似文献
57.
Due to increasing concerns about food safety and environmental issues, bio-based production of flavonoids from safe, inexpensive, and renewable substrates is increasingly attracting attention. Here, the complete biosynthetic pathway, consisting of 3-deoxy-D-arabinoheptulosonate 7-phosphate synthase (DAHPS), chorismate mutase/prephenate dehydrogenase (CM/PDH), tyrosine ammonia lyase (TAL), 4-coumarate:CoA ligase (4CL), chalcone synthase (CHS), chalcone isomerase (CHI), malonate synthetase, and malonate carrier protein, was constructed using pre-made modules to overproduce (2S)-naringenin from D-glucose. Modular pathway engineering strategies were applied to the production of the flavonoid precursor (2S)-naringenin from L-tyrosine to investigate the metabolic space for efficient conversion. Modular expression was combinatorially tuned by modifying plasmid gene copy numbers and promoter strengths to identify an optimally balanced pathway. Furthermore, a new modular pathway from D-glucose to L-tyrosine was assembled and re-optimized with the identified optimal modules to enable de novo synthesis of (2S)-naringenin. Once this metabolic balance was achieved, the optimum strain was capable of producing 100.64 mg/L (2S)-naringenin directly from D-glucose, which is the highest production titer from D-glucose in Escherichia coli. The fermentation system described here paves the way for the development of an economical process for microbial production of flavonoids. 相似文献
58.
Zewu Li Lutao Du Zhaogang Dong Yongmei Yang Xin Zhang Lili Wang Juan Li Guixi Zheng Ailin Qu Chuanxin Wang 《PloS one》2015,10(1)
Zinc finger protein 217 (ZNF217) is essential for cell proliferation and has been implicated in tumorigenesis. However, its expression and exact roles in colorectal cancer (CRC) remain unclear. In this study, we demonstrated that ZNF217 expression was aberrantly upregulated in CRC tissues and associated with poor overall survival of CRC patients. In addition, we found that ZNF217 was a putative target of microRNA (miR)-203 using bioinformatics analysis and confirmed that using luciferase reporter assay. Moreover, in vitro knockdown of ZNF217 or enforced expression of miR-203 attenuated CRC cell proliferation, invasion and migration. Furthermore, combined treatment of ZNF217 siRNA and miR-203 exhibited synergistic inhibitory effects. Taken together, our results provide new evidences that ZNF217 has an oncogenic role in CRC and is regulated by miR-203, and open up the possibility of ZNF217- and miR-203-targeted therapy for CRC. 相似文献
59.
60.
Chen-Xi Hu Hui Huang Li Zhang You Huang Zhu-Fang Shen Ke-Di Cheng Guan-Hua Du Ping Zhu 《Biotechnology letters》2009,31(7):979-984
Dipeptidyl peptidase (DPP) IV inhibitors provide a new strategy for the treatment of type 2 diabetes. Human DPP-IV gene was
cloned from differentiated Caco-2 cells and expressed in Pichia pastoris. The recombinant enzyme was used in a new system for screening of DPP-IV inhibitors. By high throughput screening, a novel
compound (W5188) was identified from 75,000 compounds with an IC50 of 6.5 μM. This method is highly reproducible and reliable for discovery of DPP-IV inhibitors as shown by Z′ value of 0.73
and S/N ratio of 6.89. 相似文献