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921.
Ming Hu Yansu Guo Huifang Chen Weisong Duan Chunyan Li 《Applied biochemistry and biotechnology》2013,170(2):301-319
Alternative splicing is a common strategy for creating functional diversities of proteins. While conventional identification of splice variants generally targets individual genes in amyotrophic lateral sclerosis, we present a novel exon-centric array that allows genome-wide identification of splice variants and concurrently provides analysis of gene expression. Compare 1 was asymptomatic SOD1G93A transgenic mice with nontransgenic littermates; compare 2 was symptomatic with asymptomatic transgenic mice. RT-PCR was performed to validate. Pathway and GO analysis were performed on abnormal genes. These findings could guide us to demonstrated the potential influence of mutant human CuZn-SOD1 and of splicing regulation in pathological processes. 相似文献
922.
Chuan Jie Cheng Quan Lei Fu Xiong Xiong Bai Shao Jin Liu Liang Shen Wu Qin Fan Hong Xia Li 《Chemical Papers》2013,67(3):336-341
A novel cationic gemini surfactant has been readily synthesised in 70 % total yield. The functional gemini surfactant can act both as an emulsifier and an atom transfer radical polymerisation (ATRP) initiator in mini-emulsion polymerisation of methyl methacrylate (MMA), in which no other emulsifier was required. 1-(Dimethylamino)dodecane (N,N-dimethyldodecylamine, DMDA) was found to be a good ligand in the activator generated by electron transfer (AGET) ATRP reaction. Kinetic studies indicated that the polymerisation featured controlled/living radical polymerisation. 相似文献
923.
Xiaodong Wen Shengchun Yang Haizhu Zhang Xia Zhao Jie Guo 《International journal of environmental analytical chemistry》2013,93(12):1243-1253
As a new developed instrument, a portable tungsten coil electrothermal atomic absorption spectrometer (W-coil ET-AAS) was first coupled with surfactant assisted dispersive liquid–liquid microextraction (SA-DLLME) to improve its analytical performance and expand its applications in this work. SA-DLLME was very simple, rapid and the extraction efficiency was considerably improved by the effect of surfactant, which was suitable to be coupled with the portable instrument in field analysis. After SA-DLLME, concentrated chromium in organic phase was directly determined on W-coil atomiser. The influence factors relevant to SA-DLLME and instrumental conditions were studied systematically. Under the optimal conditions, the limit of detection (LOD) for Cr(VI) was 0.016 µg L?1, with sensitivity enhancement factor (EF) of 107. The relative standard deviation (RSD) for seven replicate measurements of 0.5 µg L?1 of Cr(VI) was 4.6%. The recoveries for the spiked samples were in the acceptable range of 96.8–104%. The rapid, simple and high effective method greatly improved the sensitivity of this portable spectrometer for the determination of Cr(VI) and was applied to the analysis of ultra-trace Cr(VI) in real and certified water samples with satisfactory results. 相似文献
924.
Yuxia Sun Yong Zhou Hongri Liu Zhao Xia Man Luo Kai Wan Chengyan Wang 《Journal of Sol-Gel Science and Technology》2013,66(3):429-433
Highly preferentially oriented polycrystalline BiFeO3 thin film was grown on FTO/glass substrate by a sol–gel method annealed at 500 °C. XRD result showed that the film adopts highly (100) preferential orientation. SEM results indicate that the film is composed of large grains of 40–200 nm and the thickness is about 320 nm. Room temperature saturated polarization and large Pr ~55 μC/cm2 were obtained. Leakage current was substantially reduced by the controlling of ferroelectric polarization. Polarization-modulated conduction mechanism was studied. Moreover, substantial photovoltaic effect was observed. 相似文献
925.
Yong Li Xia Wen Lei Li Feng Wang Ning Zhao Fukui Xiao Wei Wei Yuhan Sun 《Journal of Sol-Gel Science and Technology》2013,66(3):353-362
A one-pot template-free route was developed for the synthesis of novel tetraethylenepentamine modified porous silica as CO2 adsorbents, the obtained materials were characterized by N2 adsorption/desorption, thermogravimetry, elemental analysis, Fourier transform infrared spectrometry,scanning electron microscopy and transmission electron microscopy. It was found that the amine species were inserted into the silica skeleton, which considerably enhanced their dispersion. Compared with similar materials derived from impregnation, the porous structure of the silica can be better reserved, leading to a promising CO2 adsorption capacity of 3.98 mmol CO2/g-adsorbent and a fast adsorption kinetic in simulated flue gas at 348 K. The resulted adsorbents could also be easily regenerated and showed a good durability in multiple adsorption–desorption cycles. All these features make this method a promising option for the preparation of CO2 adsorbents. 相似文献
926.
Yang Xu Ming Wu Yang Liu Prof. Dr. Xi‐Zeng Feng Prof. Dr. Xue‐Bo Yin Prof. Xi‐Wen He Prof. Yu‐Kui Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(7):2276-2283
Carbon dots (Cdots) are an important probe for imaging and sensing applications because of their fluorescence property, good biocompatibility, and low toxicity. However, complex procedures and strong acid treatment are often required and Cdots suffer from low photoluminescence (PL) emission. Herein, a facile and general strategy using carbonization of precursors and then extraction with solvents is proposed for the preparation of nitrogen‐doped Cdots (N‐Cdots) with 3‐(3,4‐dihydroxyphenyl)‐L ‐alanine (L ‐DOPA), L ‐histidine, and L ‐arginine as precursor models. After they are heated, the precursors become carbonized. Nitrogen‐doped Cdots are subsequently extracted into N,N′‐dimethylformamide (DMF) from the carbogenic solid. A core–shell structure of Cdots with a carbon core and the oxygen‐containing shell was observed. Nitrogen has different forms in N‐Cdots and oxidized N‐Cdots. The doped nitrogen and low oxidation level in N‐Cdots improve their emission significantly. The N‐Cdots show an emission with a nitrogen‐content‐dependent intensity and Cdot‐size‐dependent emission‐peak wavelength. Imaging of HeLa cells, a human cervical cancer cell line, and HepG2 cells, a human hepatocellular liver carcinoma line, was observed with high resolution using N‐Cdots as a probe and validates their use in imaging applications and their multicolor property in the living cell system. 相似文献
927.
928.
Dr. Ming‐Hua Xie Xiu‐Li Yang Dr. Yabing He Prof. Dr. Jian Zhang Prof. Dr. Banglin Chen Prof. Dr. Chuan‐De Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(42):14316-14321
A simple strategy to rationally immobilize metalloporphyrin sites into porous mixed‐metal–organic framework (M′MOF) materials by a metalloligand approach has been developed to mimic cytochrome P450 monooxygenases in a biological system. The synthesized porous M′MOF of [Zn2(MnOH–TCPP)(DPNI)] ? 0.5 DMF ? EtOH ? 5.5 H2O ( CZJ‐1 ; CZJ=Chemistry Department of Zhejiang University; TCPP=tetrakis(4‐carboxyphenyl)porphyrin); DPNI=N,N′‐di(4‐pyridyl)‐1,4,5,8‐naphthalenetetracarboxydiimide) has the type of doubly interpenetrated cubic α‐Po topology in which the basic Zn2(COO)4 paddle‐wheel clusters are bridged by metalloporphyrin to form two‐dimensional sheets that are further bridged by the organic pillar linker DPNI to form a three‐dimensional porous structure. The porosity of CZJ‐1 has been established by both crystallographic studies and gas‐sorption isotherms. CZJ‐1 exhibits significantly high catalytic oxidation of cyclohexane with conversion of 94 % to the mixture of cyclohexanone (K) and cyclohexanol (A) (so‐called K–A oil) at room temperature. We also provided solid experimental evidence to verify the catalytic reaction that occurred in the pores of the M′MOF catalyst. 相似文献
929.
Yan Tang Hui‐Ran Yang Hui‐Bin Sun Prof. Shu‐Juan Liu Jing‐Xia Wang Prof. Qiang Zhao Dr. Xiang‐Mei Liu Dr. Wen‐Juan Xu Prof. Sheng‐Biao Li Prof. Wei Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(4):1311-1319
Biothiols, such as cysteine (Cys) and homocysteine (Hcy), play very crucial roles in biological systems. Abnormal levels of these biothiols are often associated with many types of diseases. Therefore, the detection of Cys (or Hcy) is of great importance. In this work, we have synthesized an excellent “OFF‐ON” phosphorescent chemodosimeter 1 for sensing Cys and Hcy with high selectivity and naked‐eye detection based on an IrIII complex containing a 2,4‐dinitrobenzenesulfonyl (DNBS) group within its ligand. The “OFF‐ON” phosphorescent response can be assigned to the electron‐transfer process from IrIII center and C^N ligands to the DNBS group as the strong electron‐acceptor, which can quench the phosphorescence of probe 1 completely. The DNBS group can be cleaved by thiols of Cys or Hcy, and both the 3M LCT and 3LC states are responsible for the excited‐state properties of the reaction product of probe 1 and Cys (or Hcy). Thus, the phosphorescence is switched on. Based on these results, a general principle for designing “OFF‐ON” phosphorescent chemodosimeters based on heavy‐metal complexes has been provided. Importantly, utilizing the long emission‐lifetime of phosphorescence signal, the time‐resolved luminescent assay of 1 in sensing Cys was realized successfully, which can eliminate the interference from the short‐lived background fluorescence and improve the signal‐to‐noise ratio. As far as we know, this is the first report about the time‐resolved luminescent detection of biothiols. Finally, probe 1 has been used successfully for bioimaging the changes of Cys/Hcy concentration in living cells. 相似文献
930.
Akika Futamura Asuka Uemura Takeshi Imoto Dr. Yusuke Kitamura Dr. Hirotaka Matsuura Dr. Chun‐Xia Wang Toshiki Ichihashi Dr. Yusuke Sato Prof. Dr. Norio Teramae Prof. Dr. Seiichi Nishizawa Prof. Dr. Toshihiro Ihara 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(32):10526-10535
We propose a binary fluorimetric method for DNA and RNA analysis by the combined use of two probes rationally designed to work cooperatively. One probe is an oligonucleotide (ODN) conjugate bearing a β‐cyclodextrin (β‐CyD). The other probe is a small reporter ligand, which comprises linked molecules of a nucleobase‐specific heterocycle and an environment‐sensitive fluorophore. The heterocycle of the reporter ligand recognizes a single nucleobase displayed in a gap on the target labeled with the conjugate and, at the same time, the fluorophore moiety forms a luminous inclusion complex with nearby β‐CyD. Three reporter ligands, MNDS (naphthyridine–dansyl linked ligand), MNDB (naphthyridine–DBD), and DPDB (pyridine–DBD), were used for DNA and RNA probing with 3′‐end or 5′‐end modified β‐CyD – ODN conjugates. For the DNA target, the β‐CyD tethered to the 3′‐end of the ODN facing into the gap interacted with the fluorophore sticking out into the major groove of the gap site ( MNDS and DPDB ). Meanwhile the β‐CyD on the 5′‐end of the ODN interacted with the fluorophore in the minor groove ( MNDB and DPDB ). The results obtained by this study could be a guideline for the design of binary DNA/RNA probe systems based on controlling the proximity of functional molecules. 相似文献