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991.
Huong Le Thi Linh Le Duy Dai Do Ngoc Ogunwande Isiaka Ajani 《Chemistry of Natural Compounds》2022,58(5):939-942
Chemistry of Natural Compounds - 相似文献
992.
Wookyoung Jang Do Yeon Kim Seok Joon Mun Jun Hee Choi Yoon Ho Roh Ki Wan Bong 《Journal of polymer science. Part A, Polymer chemistry》2022,60(11):1767-1777
Polyethylene glycol (PEG) hydrogel microparticles generated via stop-flow lithography can be utilized for efficient microparticle-based cell culture processes because of their high biocompatibility, the molecular diffusion capability in the gel structure, and the tunability of their shape and size. However, the typical functionalization process of PEG microparticles with cell-adhesion promoters has inevitable limitations, requiring additional linker molecules and the preconjugation of linkers to cell-adhesion promoters and microparticles. In this study, a simple and direct cell-adhesion promoter functionalization process of the PEG microparticles is presented by use of aza-Michael reaction between remnant unreacted acrylate groups in particles and amine groups in cell-adhesion promoters. On the basis of proposed process, particles are directly conjugated with poly-l -lysine (PLL), a typical cell-adhesion promoter that can electrostatically interact with cellular membranes, in a controllable manner. We demonstrate enhanced cell-adhesion capabilities of the particles along with the increased amount of conjugated PLL in the particles. Furthermore, to validate extended applicability, the particles are directly conjugated with Gly-Arg-Gly-Asp-Ser (GRGDS) peptides, in which RGD sequence is involved in the cell-adhesion behavior of extracellular matrix proteins, including fibronectin. The introduced GRGDS peptides increase the cell-adhesion capacity of the microparticles binding to integrin proteins in cellular membranes. 相似文献
993.
Cam Van T. Do Mai Huong T. Pham Thanh Yen T. Pham Cuc T. Dinh Thu Uyen T. Bui Thuan Dang Tran Van Tuyen Nguyen 《Current Opinion in Green and Sustainable Chemistry》2022
Domestic wastewaters are produced in huge volumes and abundant with carbon, nitrogen and phosphorous, which are a promising source of nutrients for production of microalgae. Microalgae-based bioremediation of domestic wastewater offers various advantages over traditional treatment approaches because the process consumes CO2, completely removes nitrogen and phosphorous for production of green biomass and oxygen. Moreover, the abundance of biochemical compositions (e.g., lipids, proteins, carbohydrates, bioactive compounds) of microalgae biomass is superior to terrestrial plant biomass in refining to multi-products having variety of commercial values. In this review, the most dominant microalgae used for simultaneous removal of pollutants and production of biomass and metabolites from domestic wastewater are presented. Biorefinery of microalgae biomass produced from domestic wastewater for production of multiple products is also explored. Finally, challenges and perspectives of successful microalgae-based bioremediation of domestic wastewater toward the biorefinery are briefly discussed. 相似文献
994.
Woojin Jeon Sang Ho Rha Woongkyu Lee Cheol Hyun An Min Jung Chung Sang Hyun Kim Cheol Jin Cho Seong Keun Kim Cheol Seong Hwang 《固体物理学:研究快报》2015,9(7):410-413
The energy diagram of RuO2/Al‐doped TiO2/RuO2 structures was estimated from the capacitance–voltage and leakage current density–voltage curves. The Al‐doping profile in TiO2 film was varied by changing position of the atomic layer deposition cycle of Al2O3 during the atomic layer deposition of 9 nm‐thick TiO2 film. The interface between the TiO2 film and the RuO2 electrode containing Al‐doping layer showed a higher Schottky barrier by 0.1 eV compared with the opposite interface without the doping layer. The evolution of various leakage current profiles upon increasing the bias with opposite polarity could be well explained by the asymmetric Schottky barrier. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
995.
996.
Calcium Carbonate Mineralized Nanoparticles as an Intracellular Transporter of Cytochrome c for Cancer Therapy 下载免费PDF全文
Ahn Na Koo Kyung Hyun Min Hong Jae Lee Jun Ho Jegal Jae Won Lee Prof. Dr. Sang Cheon Lee 《化学:亚洲杂志》2015,10(11):2380-2387
A new intracellular delivery system based on an apoptotic protein‐loaded calcium carbonate (CaCO3) mineralized nanoparticle (MNP) is described. Apoptosis‐inducing cytochrome c (Cyt c) loaded CaCO3 MNPs (Cyt c MNPs) were prepared by block copolymer mediated in situ CaCO3 mineralization in the presence of Cyt c. The resulting Cyt c MNPs had a vaterite polymorph of CaCO3 with a mean hydrodynamic diameter of 360.5 nm and exhibited 60 % efficiency for Cyt c loading. The Cyt c MNPs were stable at physiological pH (pH 7.4) and effectively prohibited the release of Cyt c, whereas, at intracellular endosomal pH (pH 5.0), Cyt c release was facilitated. The MNPs enable the endosomal escape of Cyt c for effective localization of Cyt c in the cytosols of MCF‐7 cells. Flow cytometry showed that the Cyt c MNPs effectively induced apoptosis of MCF‐7 cells. These findings indicate that the CaCO3 MNPs can meet the prerequisites for delivery of cell‐impermeable therapeutic proteins for cancer therapy. 相似文献
997.
A large eddy simulation (LES) is performed for turbulent flow around a bluff body inside a sudden expansion cylinder chamber,
a configuration which resembles a premixed gas turbine combustor. To promote turbulent mixing and to accommodate flame stability,
a flame holder is installed inside the combustion chamber. The Smagorinsky model and the Lagrangian dynamic subgrid-scale
model are employed and tested. The calculated Reynolds number is 5,000 based on the bulk velocity and the diameter of inlet
pipe. The simulation code is constructed by using a general coordinate system based on the physical contravariant velocity
components. The predicted turbulent statistics are evaluated by comparing with the laser-doppler velocimetry (LDV) measurement
data. The agreement of LES with the experimental data is shown to be satisfactory. Emphasis is placed on the time-dependent
evolutions of turbulent vortical structures behind the flame holder. The numerical flow visualizations depict the behavior
of large-scale vortices. The turbulent behavior behind the flame holder is analyzed by visualizing the sectional views of
vortical structure.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
998.
In this paper, nonlinear matrix equations of the form X + A*f1 (X)A + B*f2 (X)B = Q are discussed. Some necessary and sufficient conditions for the existence of solutions for this equation are derived. It is shown that under some conditions this equation has a unique solution, and an iterative method is proposed to obtain this unique solution. Finally, a numerical example is given to identify the efficiency of the results obtained. 相似文献
999.
Expression, High Cell Density Culture and Purification of Recombinant EC-SOD in Escherichia coli 总被引:1,自引:0,他引:1
Young-Jin Son Ji-Young Bae Seon-Ha Chong Hui Sun Lee Sang Hyun Mo Tae Yoon Kim Han Choe 《Applied biochemistry and biotechnology》2010,162(6):1585-1598
Superoxide dismutase (SOD) catalyzes the dismutation of the biologically toxic superoxide anion into oxygen and hydrogen peroxide and is deployed by the immune system to kill invading microorganisms. Extracellular SOD (EC-SOD) is a copper- and zinc-containing glycoprotein found predominantly in the soluble extracellular compartment that consists of ~30-kDa subunits. Here, we purified recombinant EC-SOD3 (rEC-SOD) from Escherichia coli BL21(DE3) expressing a pET-SOD3-1 construct. Cells were cultured by high-density fed-batch fermentation to a final OD600 of 51.8, yielding a final dry cell weight of 17.6 g/L. rEC-SOD, which was expressed as an inclusion body, comprised 48.7% of total protein. rEC-SOD was refolded by a simple dilution refolding method and purified by cation-exchange and reverse-phase chromatography. The highly purified rEC-SOD thus obtained was a mixture of monomers and dimers, both of which were active. The molecular weights of monomeric and dimeric rEC-SOD were 25,255 and 50,514 Da, respectively. The purified rEC-SOD had 4.3 EU/mg of endotoxin and the solubility of rEC-SOD was more than 80% between pH 7 and 10. In 2 L of fed-batch fermentation, 60 mg of EC-SOD (99.9% purity) could be produced and total activity was 330.24 U. The process established in this report, involving high-cell-density fermentation, simple dilution refolding, and purification with ion-exchange and reverse-phase chromatography, represents a commercially viable process for producing rEC-SOD. 相似文献
1000.
The excited-state lifetime of supersonically cooled adenine was measured in the gas phase by femtosecond pump-probe transient ionization as a function of excitation energy between 36?100 and 37?500cm(-1). The excited-state lifetime of adenine is ~2ps around the 0-0 band of the (1)L(b) ππ(?) state (36?105cm(-1)). The lifetime drops to ~1ps when adenine is excited to the (1)L(a) ππ(?) state with the pump energy at 36?800cm(-1) and above. The excited-state lifetimes of (1)L(a) and (1)L(b) ππ(?) states are differentiated in accordance with previous frequency-resolved and computational studies. 相似文献