http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Adsorption of Nucleotides on ${\beta}$-Cyclodextrin Derivative Grafted Chitosan
Xiao Jian-Bo,Yu Hong-Zhu,Xu Ming,Chen Xiao-Qing The Polymer Society of Korea 2006 Macromolecular Research Vol.14 No.4
A novel ${\beta}$-cyclodextrin derivative (CCD-C) was synthesized with chitosan and carboxymethyl-${\beta}$-cyclodextrin. Its structure was characterized by elemental analysis, infrared spectra analysis, and X-ray diffraction analysis. The adsorption properties for guanosine 5'-monophosphate, cytidine 5'-monophosphate and uridine 5'-monophosphate were studied. Experimental results demonstrated that CCD-C had higher adsorption capability for guanosine 5'-monophosphate, and that the adsorption capacity for guanosine 5'-monophosphate was 74.20mg/g. The adsorption capacity was greatly influenced by pH, time and temperature. The introduction of chitosan enhanced the adsorption ability and adsorption selectivity of ${\beta}$-cyclodextrin for guanosine 5'-monophosphate. This novel derivative of chitosan is expected to have wide applications in the separation, concentration and analysis of nucleotides in biological samples.
Adsorption of Nucleotides on ß-Cyclodextrin Derivative Grafted Chitosan
Jian Bo Xiao,Xiao Qing Chen,Hong Zhu Yu,Ming Xu 한국고분자학회 2006 Macromolecular Research Vol.14 No.4
A novel ß-cyclodextrin derivative (CCD-C) was synthesized with chitosan and carboxymethyl-ß-cyclodextrin. Its structure was characterized by elemental analysis, infrared spectra analysis, and X-ray diffraction analysis. The adsorption properties for guanosine 5'-monophosphate, cytidine 5'-monophosphate and uridine 5'-monophosphate were studied. Experimental results demonstrated that CCD-C had higher adsorption capability for guanosine 5'-mono phosphate, and that the adsorption capacity for guanosine 5'-monophosphate was 74.20mg/g. The adsorption capacity was greatly influenced by pH, time and temperature. The introduction of chitosan enhanced the adsorption ability and adsorption selectivity of ß-cyclodextrin for guanosine 5'-monophosphate. This novel derivative of chitosan is expected to have wide applications in the separation, concentration and analysis of nucleotides in biological samples.
( Yi-xiao Ma ),( Xiao-han Wu ),( Hui-shi Wu ),( Zhan-bo Dong ),( Jian-hui Ye ),( Xin-qiang Zheng ),( Yue-rong Liang ),( Jian-liang Lu ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.7
The degradation efficiency and catabolism pathways of the different methylxanthines (MXs) in isolated caffeine-tolerant strain Pseudomonas putida CT25 were comprehensively studied. The results showed that the degradation efficiency of various MXs varied with the number and position of the methyl groups on the molecule (i.e., xanthine > 7-methylxanthine ≈ theobromine > caffeine > theophylline > 1-methylxanthine). Multiple MX catabolism pathways coexisted in strain CT25, and a different pathway would be triggered by various MXs. Demethylation dominated in the degradation of N-7-methylated MXs (such as 7- methylxanthine, theobromine, and caffeine), where C-8 oxidation was the major pathway in the catabolism of 1-methylxanthine, whereas demethylation and C-8 oxidation are likely both involved in the degradation of theophylline. Enzymes responsible for MX degradation were located inside the cell. Both cell culture and cell-free enzyme assays revealed that N-1 demethylation might be a rate-limiting step for the catabolism of the MXs. Surprisingly, accumulation of uric acid was observed in a cell-free reaction system, which might be attributed to the lack of activity of uricase, a cytochrome c-coupled membrane integral enzyme.
Jian Ma,Dingquan Xiao,Bo Wu,Jia-gang Wu,Jian-guo Zhu 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.65 No.2
0.95(Na0.96−xKxLi0.04)(Nb0.89Sb0.07Ta0.04)O3-0.05KNbO3 (abbreviated as KxNLNST-KN, x =0.32 − 0.52) lead-free piezoelectric ceramics were prepared by using the conventional solid-statesintering method, and the intentional addition of a pre-calcined KNbO3 powder was used as asintering aid that might inhibit and compensate for the volatilization of alkali metals during thesintering process. The preparation of the ceramics and the effects of K/Na ratio on the structureand the electrical properties of these ceramics were studied in detail. Compared with the relativelyhigher sintering temperature of Li-, Sb-, and Ta-modified KNN ceramics reported in the literature,the dense ceramic samples were obtained at a reduced temperature of 1060 C, and the ceramicswith x = 0.44 possessed optimal properties: d33 = 298 pC/N, kp = 48%, Pr = 21.9 μC/cm2, andEc = 11.5 kV/cm.
Xiao-bo Wang,Hui-yuan Gao,Bai-ling Hou,Jian Huang,Rong-gang Xi,Li-jun Wu 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.5
Nanoparticle realgar powders (NRP) inhibited U937 cell growth in a time and dose-dependent manner. U937 cells treated with NRP showed typical characteristics of apoptosis including the morphological changes and DNA fragmentation. Caspase family inhibitor (z-VAD-fmk), caspase-8, -9 inhibitor (z-IETD-fmk, Ac-LEHD-CHO, respectively) and caspase-3 inhibitor (z- DEVD-fmk) partially prevented NRP -induced apoptosis. Moreover, the classical substrates of caspase-3, poly-ADP ribose polymerase (PARP) was degraded after U937 cells treatment with NRP. In addition, NRP increased the ratio of Bax/Bcl-2 protein expression. Although p38 inhibitor (SB203580) and ERK inhibitor (PD98059) failed to block cell death, JNK inhibitor (SP600125) had marked inhibitory effects on NRP -induced apoptosis. Furthermore, the phosphorylation of JNK was up-regulated, suggesting that JNK was responsible for NRP -induced apoptosis in U937 cells. These results suggested that the caspase, mitochondria and MAPK signal pathways were involved in NRP-induced U937 apoptosis.
Jian Sun,Shi-Jie Zhang,Hai-Bo Li,Wei Zhou,Wei-Xiao Hu,Shang Shan 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.5
Twenty two new 5-fluorouracil (5-FU) derivatives, 2-butoxy-4-substituted 5-fluoropyrimidines, were synthesized and characterized by IR, 1H NMR, MS, HRMS. All compounds were preliminarily evaluated by MTT assay on human liver BEL-7402 cancer cell line in vitro. Ten compounds were selected to test their cytotoxic activity against A549, HL-60 and MCF-7 cancer cell lines in vitro. These compounds were more sensitive to BEL-7402 than other cell lines, particularly, cytotoxic activity of compounds 6b, 6d-f, 6p, 6s-u were in sub-micromolar scale. The highest cytotoxic potency against A549, HL-60 and MCF-7 was shown by 2-butoxy-4-chloro-5- fluoropyrimidine (5) with IC50 values of 0.10, 1.66 and 0.59 μM, respectively. Compounds 6d and 6e were effective against MCF-7 with IC50 9.73 μM and HL-60 with IC50 8.83 μM, respectively.
Preparation of Homogeneous Microstructure Pure Lead Metaniobate by Two-Step Sintering
Xiao-gang Zhao,Peng Liu,Bo Chao,Su Juan Liu,Ming Pang,Xiao-Ming Chen,Jian-Ping Zhou 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.1
The purpose of the present work is to obtain the Lead metaniobate ceramics with the orthorhombic phase via a two-step sintering method. The samples were first sintered at 1320°C for 10 min, and then sintered separately at 1260°C, 1220°C, and 1180°C for 4 h. All the ceramics show orthorhombic phase and homogeneous microstructure. It was found that the abnormal grain growth was restrained obviously.
( Xiao Fen Jin ),( Bo Zhu ),( Ri He Peng ),( Hai Hua Jiang ),( Jian Min Chen ),( Jing Zhuang ),( Jian Zhang ),( Quan Hong Yao ),( Ai Sheng Xiong ) 생화학분자생물학회 (구 한국생화학분자생물학회) 2010 BMB Reports Vol.43 No.8
In this study, we cloned the ERF-B3 subfamily transcription factor gene BnaERF-B3-hy15 from Brassica napus L. Huyou15. This 600 bp gene encodes a 199 amino acid classic ethylene responsive factor (ERF), which shown no binding or very weak binding GCC box-binding activity by the yeast one-hybrid assay. We used gene shuffling and the yeast one-hybrid system to obtain three mutated sequences that can bind to the GCC box. Sequence analysis indicated that two residues, Gly156 in the AP2 domain and Phe62 at the N-terminal domain were mutated to arginine and serine, respectively. Changes of Gly156 to arginine and Phe62 to serine increased the GCC- binding activity of BnaERF-B3-hy15 and the alter of Gly156 to arginine changed the AP2-domain structure of BnaERF-B3- hy15. [BMB reports 2010; 43(8): 567-572]