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901.
Zhen Xing Zhang Qi Xin Zheng Yong Chao Wu Ding Jun Hao 《Biotechnology and Bioprocess Engineering》2010,15(4):545-551
In this study, we evaluated the behavior of neural stem cells (NSCs) using a new peptide hydrogel scaffold named IKVAVmx,
which was made by mixing self-assembling peptide RADA16 and designer peptide RADA16-IKVAV solutions. NSCs derived from rat
cerebral cortex were culture-expanded in neuorobasal medium and seeded on the RADA16 and IKVAVmx hydrogels. Cells could penetrate
the hydrogels and form a 3D cellular network. Compared to pure RADA16 scaffold, we found that IKVAVmx scaffold significantly
promoted cell proliferation and stimulated cell migration into the 3D scaffold. Moreover, Immunocytochemistry and Western
blot analysis indicated that the differentiation ratio of neurons from NSCs in IKVAVmx scaffold was higher than that in pure
RADA16 scaffold. These results suggested that this new hydrogel scaffold provided an ideal substrate for NSCs 3D culture and
suggested its further application for neural tissue engineering. 相似文献
902.
Feng Yan Xiaobei Deng Junpeng Yan Jiancheng Wang Lunguang Yao Songya lv Yipeng Qi Hua Xu 《Journal of microbiology (Seoul, Korea)》2010,48(2):199-205
The inhibitor of apoptosis proteins (IAP) plays an important role in cell apoptosis. We cloned two novel IAP family members,
Ap-iap1 and Ap-iap2, from Antheraea pernyi nucleopolyhedrovirus (ApNPV) genome. Ap-IAP1 contains two baculoviral IAP repeat (BIR) domains followed by a RING domain,
but Ap-IAP2 has only one BIR domain and RING. The result of transient expression in Spodoptera frugiperda (Sf21) showed that Ap-iap1 blocked cell apoptosis induced by actinomycin D treatment and also rescued the p35 deficient Autographa californica nucleopolyhedrovirus (AcNPV) to replicate in Sf9 cells, while Ap-iap2 does not have this function. Several Ap-IAP1 truncations were constructed to test the activity of BIRs or RING motif to inhibit
cell apoptosis. The results indicated that BIRs or RING of Ap-IAP1 had equally function to inhibit cell apoptosis. Therefore
deletion of above both of the above domains could not block apoptosis induced by actinomycin D or rescue the replication of
AcMNPVΔp35. We also screened two phage-display peptides that might interact with Ap-IAP1. 相似文献
903.
Xueyong Zhou Wei Qi Jianbo Zhang Tingting Zou Chen Guo 《Biocontrol Science and Technology》2010,20(8):841-852
Effects of minerals on the conformational changes of protoxin isolated from Bacillus thuringiensis were investigated by circular dichroism and fluorescence spectroscopy. Contact of the protoxin with attapulgite, montmorillonite and kaolinite for 3 h resulted in no significant changes in the spectra of circular dichroism and a slight decrease in the fluorescence intensity. There were significant changes in spectra of circular dichroism of protoxin after desorption in comparison to the native protoxin. The fluorescence intensity of protoxins desorbed from minerals retained 77.5, 63.7 and 60.4% of intensity of native protoxin, respectively. The influential extent of desorption on the secondary structure was higher than that of contact. 相似文献
904.
Wang Qian Zhang Hanxing Chen Quan Chen Xiulan Zhang Yuzhong Qi Qingsheng 《World journal of microbiology & biotechnology》2010,26(6):1149-1153
A deep-sea psychrotrophic bacterium Pseudoaltermonas sp. SM9913, isolated from abyssalbenthic sediments in Bohai Sea, was found to be able to synthesize polyhydroxyalkanoate (PHA)
polymer consisting of mainly 3-hydroxydecanoate and 3-hydroxydodecanoate. PHA accumulation in Pseudoaltermonas sp. SM9913 was confirmed by transmission electron microscope, Nile red dye and gas chromatography/mass spectral. The PHA content
was determined as high as 2–3% of cell dry weight when the strain was grown in a sea water-based liquid medium. The relationship
between PHA and exopolysaccharide accumulation in this strain was discussed. 相似文献
905.
Discovery and synthesis of 6,7,8,9-tetrahydro-5H-pyrimido-[4,5-d]azepines as novel TRPV1 antagonists
Hawryluk NA Merit JE Lebsack AD Branstetter BJ Hack MD Swanson N Ao H Maher MP Bhattacharya A Wang Q Freedman JM Scott BP Wickenden AD Chaplan SR Breitenbucher JG 《Bioorganic & medicinal chemistry letters》2010,20(23):7137-7141
Utilization of a tetrahydro-pyrimdoazepine core as a bioisosteric replacement for a piperazine-urea resulted in the discovery a novel series of potent antagonists of TRPV1. The tetrahydro-pyrimdoazepines have been identified as having good in vitro and in vivo potency and acceptable physical properties. 相似文献
906.
An efficient system to detect protein ubiquitination by agroinfiltration in Nicotiana benthamiana 总被引:1,自引:0,他引:1
Lijing Liu Yiyue Zhang Sanyuan Tang Qingzhen Zhao Zhonghui Zhang Huawei Zhang Li Dong Huishan Guo Qi Xie 《The Plant journal : for cell and molecular biology》2010,61(5):893-903
The ubiquitination proteasome pathway has been demonstrated to regulate all plant developmental and signaling processes. E3 ligase/substrate‐specific interactions and ubiquitination play important roles in this pathway. However, due to technical limitations only a few instances of E3 ligase–substrate binding and protein ubiquitination in plants have been directly evidenced. An efficient in vivo and in vitro ubiquitination assay was developed for analysis of protein ubiquitination reactions by agroinfiltration expression of both substrates and E3 ligases in Nicotiana benthamiana. Using a detailed analysis of the well‐known E3 ligase COP1 and its substrate HY5, we demonstrated that this assay allows for fast and reliable detection of the specific interaction between the substrate and the E3 ligase, as well as the effects of MG132 and substrate ubiquitination and degradation. We were able to differentiate between the original and ubiquitinated forms of the substrate in vivo with antibodies to ubiquitin or to the target protein. We also demonstrated that the substrate and E3 ligase proteins expressed by agroinfiltration can be applied to analyze ubiquitination in in vivo or in vitro reactions. In addition, we optimized the conditions for different types of substrate and E3 ligase expression by supplementation with the gene‐silencing suppressor p19 and by time‐courses of sample collection. Finally, by testing different protein extraction buffers, we found that different types of buffer should be used for different ubiquitination analyses. This method should be adaptable to other protein modification studies. 相似文献
907.
Jared Cumming Suresh Babu Ying Huang Carolyn Carrol Xia Chen Leonard Favreau William Greenlee Tao Guo Matthew Kennedy Reshma Kuvelkar Thuy Le Guoqing Li Nansie McHugh Peter Orth Lynne Ozgur Eric Parker Kurt Saionz Andrew Stamford Corey Strickland Dawit Tadesse Qi Zhang 《Bioorganic & medicinal chemistry letters》2010,20(9):2837-2842
With collaboration between chemistry, X-ray crystallography, and molecular modeling, we designed and synthesized a series of novel piperazine sulfonamide BACE1 inhibitors. Iterative exploration of the non-prime side and S2′ sub-pocket of the enzyme culminated in identification of an analog that potently lowers peripheral Aβ40 in transgenic mice with a single subcutaneous dose. 相似文献
908.
Guozhi Tang Denis J. Kertesz Minmin Yang Xianfeng Lin Zhanguo Wang Wentao Li Zongxing Qiu Junli Chen Jianghua Mei Li Chen Taraneh Mirzadegan Seth F. Harris Armando G. Villaseñor Jennifer Fretland William L. Fitch Julie Qi Hang Gabrielle Heilek Klaus Klumpp 《Bioorganic & medicinal chemistry letters》2010,20(20):6020-6023
909.
Xin-Hua Liu Hui-Feng Liu Xu Shen Bao-An Song Pinaki S. Bhadury Hai-Liang Zhu Jin-Xing Liu Xing-Bao Qi 《Bioorganic & medicinal chemistry letters》2010,20(14):4163-4167
A series of novel 2-chloro-pyridine derivatives containing flavone, chrome or dihydropyrazole moieties as potential telomerase inhibitors were synthesized. The bioassay tests showed that compounds 6e and 6f exhibited some effect against gastric cancer cell SGC-7901 with IC50 values of 22.28 ± 6.26 and 18.45 ± 2.79 μg/mL, respectively. All title compounds were assayed for telomerase inhibition by a modified TRAP assay, the results showed that compound 6e can strongly inhibit telomerase with IC50 value of 0.8 ± 0.07 μM. Docking simulation was performed to position compound 6e into the active site of telomerase (3DU6) to determine the probable binding model. 相似文献
910.
利用大肠杆菌工程菌廉价高效生产聚羟基丁酸酯 总被引:1,自引:0,他引:1
利用大肠杆菌生产聚羟基脂肪酸酯是近来国际上生物可降解塑料的研究热点,本研究通过对适宜于聚羟基脂肪酸酯生产的大肠杆菌菌株的选择和碳源利用试验,初步确立了大肠杆菌代谢工程改造生产聚羟基脂肪酸酯的基础。并在此基础上,通过对大肠杆菌磷酸烯醇式丙酮酸葡萄糖转移酶系统的改造和工程菌环境诱导系统的应用,解决了大肠杆菌工程菌无法同时利用多种碳源合成聚羟基脂肪酸酯的难题。发酵试验证明,工程化改造的大肠杆菌利用廉价底物在5L发酵罐中分批培养32h后,菌体终浓度能够达到8.24g/L,聚羟基脂肪酸酯占细胞干重的84.6%。 相似文献