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941.
Feng Lan Andrew S. Lee Ping Liang Veronica Sanchez-Freire Patricia K. Nguyen Li Wang Leng Han Michelle Yen Yongming Wang Ning Sun Oscar J. Abilez Shijun Hu Antje D. Ebert Enrique G. Navarrete Chelsey S. Simmons Matthew Wheeler Beth Pruitt Richard Lewis Joseph C. Wu 《Cell Stem Cell》2013,12(1):101-113
942.
Fei Chen Mengxing Dong Meng Ge Lingxiang Zhu Lufeng Ren Guocheng Liu Rong Mu 《基因组蛋白质组与生物信息学报(英文版)》2013,11(1):34-40
DNA sequencing using reversible terminators, as one sequencing by synthesis strategy, has garnered a great deal of interest due to its popular application in the second-generation high-throughput DNA sequencing technology. In this review, we provided its history of development, classification, and working mechanism of this technology. We also outlined the screening strategies for DNA polymerases to accommodate the reversible terminators as substrates during polymerization; particularly, we introduced the "REAP" method developed by us. At the end of this review, we discussed current limitations of this approach and provided potential solutions to extend its application. 相似文献
943.
The advent of induced pluripotent stem cells (iPSCs) has revolutionized the concept of cellular reprogramming and potentially will solve the immunological compatibility issues that have so far hindered the application of human pluripotent stem cells in regenerative medicine. Recent findings showed that pluripotency is defined by a state of balanced lineage potency, which can be artificially instated through various procedures, including the conventional Yamanaka strategy. As a type of pluripotent stem cell, iPSCs are subject to the usual concerns over purity of differen- tiated derivatives and risks of tumor formation when used for cell-based therapy, though they pro- vide certain advantages in translational research, especially in the areas of personalized medicine, disease modeling and drug screening, iPSC-based technology, human embryonic stem cells (hESCs) and direct lineage conversion each will play distinct roles in specific aspects of translational medi- cine, and continue yielding surprises for scientists and the public. 相似文献
944.
Calcium borohydride is a potential candidate for onboard hydrogen storage because it has a high gravimetric capacity (11.5 wt.%) and a high volumetric hydrogen content (~130 kg m?3). Unfortunately, calcium borohydride suffers from the drawback of having very strongly bound hydrogen. In this study, Ca(BH4)2 was predicted to form a destabilized system when it was mixed with LiBH4, NaBH4, or KBH4. The release of hydrogen from Ca(BH4)2 was predicted to proceed via two competing reaction pathways (leading to CaB6 and CaH2 or CaB12H12 and CaH2) that were found to have almost equal free energies. Using a set of recently developed theoretical methods derived from first principles, we predicted five new hydrogen storage reactions that are among the most attractive of those presently known. These combine high gravimetric densities (>6.0 wt.% H2) with have low enthalpies [approximately 35 kJ/(mol?1 H2)] and are thermodynamically reversible at low pressure within the target window for onboard storage that is actively being considered for hydrogen storage applications. Thus, the first-principles theoretical design of new materials for energy storage in future research appears to be possible. Figure
Calculated van’t Hoff plot for reactions (10-24*) listed in the Ca-M(Li, Na, K)-B-H system (Tables 2–4). The region within the rectangular box corresponds to desirable temperatures and pressures for on-board hydrogen storage PH2 = 1-700 bar and T = 233 to +355 K 相似文献
945.
Ren‐Hua Chen Yi‐Gang Li Kun‐Li Jiao Peng‐Pai Zhang Yu Sun Li‐Ping Zhang Xiang‐Fei Fong Wei Li Yi Yu 《Journal of cellular and molecular medicine》2013,17(5):608-616
The expression of the chemorepellent Sema3a is inversely related to sympathetic innervation. We investigated whether overexpression of Sema3a in the myocardial infarction (MI) border zone could attenuate sympathetic hyper‐innervation and decrease the vulnerability to malignant ventricular tachyarrhythmia (VT) in rats. Survived MI rats were randomized to phosphate buffered saline (PBS, n = 12); mock lentivirus (MLV, n = 13) and lentivirus‐mediated overexpression of Sema3a (SLV, n = 13) groups. Sham‐operated rats served as control group (CON, n = 20). Cardiac function and electrophysiological study (PES) were performed at 1 week later. Blood and tissue samples were collected for histological analysis, epinephrine (EPI), growth‐associated factor 43 (GAP43) and tyrosine hydroxylase (TH) measurements. QTc intervals were significantly shorter in SLV group than in PBS and MLV groups (168.6 ± 7.8 vs. 178.1 ± 9.5 and 180.9 ± 8.2 ms, all P < 0.01). Inducibility of VT by PES was significantly lower in the SLV group [30.8% (4/13)] than in PBS [66.7% (8/12)] and MLV [61.5% (8/13)] groups (P < 0.05). mRNA and protein expressions of Sema3a were significantly higher and the protein expression of GAP43 and TH was significantly lower at 7 days after transduction in SLV group compared with PBS, MLV and CON groups. Myocardial EPI in the border zone was also significantly lower in SLV group than in PBS and MLV group (8.73 ± 1.30 vs. 11.94 ± 1.71 and 12.24 ± 1.54 μg/g protein, P < 0.001). Overexpression of Sema3a in MI border zone could reduce the inducibility of ventricular arrhythmias by reducing sympathetic hyper‐reinnervation after infarction. 相似文献
946.
Tingxiu Xiang Lili Li Xuedong Yin Lan Zhong Weiyan Peng Zhu Qiu Guosheng Ren Qian Tao 《Journal of cellular and molecular medicine》2013,17(10):1236-1246
Dickkopf‐related protein 3 (DKK3) is an antagonist of Wnt ligand activity. Reduced DKK3 expression has been reported in various types of cancers, but its functions and related molecular mechanisms in breast tumorigenesis remain unclear. We examined the expression and promoter methylation of DKK3 in 10 breast cancer cell lines, 96 primary breast tumours, 43 paired surgical margin tissues and 16 normal breast tissues. DKK3 was frequently silenced in breast cell lines (5/10) by promoter methylation, compared with human normal mammary epithelial cells and tissues. DKK3 methylation was detected in 78% of breast tumour samples, whereas only rarely methylated in normal breast and surgical margin tissues, suggesting tumour‐specific methylation of DKK3 in breast cancer. Ectopic expression of DKK3 suppressed cell colony formation through inducing G0/G1 cell cycle arrest and apoptosis of breast tumour cells. DKK3 also induced changes of cell morphology, and inhibited breast tumour cell migration through reversing epithelial‐mesenchymal transition (EMT) and down‐regulating stem cell markers. DKK3 inhibited canonical Wnt/β‐catenin signalling through mediating β‐catenin translocation from nucleus to cytoplasm and membrane, along with reduced active‐β‐catenin, further activating non‐canonical JNK signalling. Thus, our findings demonstrate that DKK3 could function as a tumour suppressor through inducing apoptosis and regulating Wnt signalling during breast tumorigenesis. 相似文献
947.
Qing-guo Wei Wen-jing Shi Fu-de Ren Yong Wang Jun Ren 《Journal of molecular modeling》2013,19(1):453-463
The changes of bond dissociation energy (BDE) in the C–NO2 bond and nitro group charge upon the formation of the molecule-cation interaction between Na+ and the nitro group of 14 kinds of nitrotriazoles or methyl derivatives were investigated using the B3LYP and MP2(full) methods with the 6-311++G**, 6-311++G(2df,2p) and aug-cc-pVTZ basis sets. The strength of the C–NO2 bond was enhanced in comparison with that in the isolated nitrotriazole molecule upon the formation of molecule-cation interaction. The increment of the C–NO2 bond dissociation energy (ΔBDE) correlated well with the molecule-cation interaction energy. Electron density shifts analysis showed that the electron density shifted toward the C-NO2 bond upon complex formation, leading to the strengthened C-NO2 bond and the possibly reduced explosive sensitivity. Figure
C1-N2 bond turns strong upon molecule-cation interaction formation, leading to a possibly reduced explosive sensitivity. 相似文献
948.
The interaction between M (M?=?Ca, Yb) atom and C74 (D 3h) has been investigated by all electron relativistic density function theory. With the aid of the representative patch of C74 (D 3h), we studied the interaction between C74 (D 3h) and M (M?=?Ca, Yb) atom and obtained the interaction potential. Optimized structures show that there are three equivalent stable isomers and there is one transition state between every two stable isomers. According to the minimum energy pathway, the possible movement trajectory of M (M?=?Ca, Yb) atom in the C74 (D 3h) cage is explored. The calculated energy barrier for Yb atoms moving from the stable isomer to the transition state is 10.4 kcal mol?1 and the energy barrier for Ca atoms is 6.1 kcal mol?1. The calculated NMR spectra of M@C74 (M?=?Ca, Yb) are in good agreement with the experimental data. There are nine lines in the spectra: one 1/6 intensity signal, four half intensity signals and four full intensity signals. 相似文献
949.
Hao Chen Linfeng Hu Yan Yan Renchao Che Min Chen Limin Wu 《Liver Transplantation》2013,3(12):1636-1646
A facile one‐step hydrothermal co‐deposition method for growth of ultrathin Ni(OH)2‐MnO2 hybrid nanosheet arrays on three dimensional (3D) macroporous nickel foam is presented. Due to the highly hydrophilic and ultrathin nature of hybrid nanosheets, as well as the synergetic effects of Ni(OH)2 and MnO2, the as‐fabricated Ni(OH)2‐MnO2 hybrid electrode exhibits an ultrahigh specific capacitance of 2628 F g?1. Moreover, the asymmetric supercapacitor with the as‐obtained Ni(OH)2‐MnO2 hybrid film as the positive electrode and the reduced graphene oxide as the negative electrode has a high energy density (186 Wh kg?1 at 778 W kg?1), based on the total mass of active materials. 相似文献
950.
Dominic Bresser Elie Paillard Richard Kloepsch Steffen Krueger Martin Fiedler René Schmitz Dietmar Baither Martin Winter Stefano Passerini 《Liver Transplantation》2013,3(4):513-523
The preparation and electrochemical characterization of a new material consisting of carbon coated ZnFe2O4 nanoparticles is presented. This material, which offers an interesting combination of alloying and conversion mechanisms, is capable of hosting up to nine equivalents of lithium per unit formula, corresponding to an exceptional specific capacity, higher than 1000 mAh g?1. Composite electrodes of such a material, prepared using environmentally friendly sodium carboxymethyl cellulose as binder, showed the highest, ever reported, specific capacity and high rate performance upon long‐term testing. Furthermore, in situ X‐ray diffraction analysis allowed identifying the reduction process occurring upon initial lithiation. 相似文献