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Insulin-like growth factor II blocks apoptosis of N-myc2-expressing woodchuck liver epithelial cells
N-myc2 and insulin-like growth factor II (IGF-II) are coordinately overexpressed in the great majority of altered hepatic foci, which are the earliest precancerous lesions observed in the liver of woodchuck hepatitis virus carrier woodchucks, and these genes continue to be overexpressed in hepatocellular carcinomas (HCCs). We have investigated the function of these genes in woodchuck hepatocarcinogenesis by using a woodchuck liver epithelial cell line (WC-3). WC-3 cells react positively with a monoclonal antibody (12.8.5) against woodchuck oval cells, suggesting a lineage relationship with oval cells. Overexpression of N-myc2 in three WC-3 cell lines caused their morphological transformation and increased their growth rate and saturation density in medium containing 10% serum. Removal of serum from the medium increased cell death of the N-myc2-expressing lines, whereas cell death in control lines was minimal. The death of N-myc2-expressing WC-3 cells was accompanied by nucleosomal fragmentation of cellular DNA, and DAPI (4',6-diamidino-2-phenylindole) staining revealed condensation and fragmentation of the nuclei, suggesting that N-myc2-expressing WC-3 cells undergo apoptosis in the absence of serum. In colony regression assays, conducted in the absence of serum, control colonies were stable, while N-myc2-expressing colonies regressed to various degrees. Addition of recombinant human IGF-II to the serum-free medium blocked both cell death and colony regression in all the N-myc2-expressing lines. Therefore, coordinate overexpression of N-myc2 and IGF-II in woodchuck altered hepatic foci may allow cells which otherwise might die to survive and progress to hepatocellular carcinoma. 相似文献
54.
Under normal physiologic conditions the level of circulating red blood cells is regulated precisely by the glycoprotein erythropoietin. In major elective surgery, patients who are participating in preoperative autologous blood donation or who are anemic may not have the capacity to manufacture sufficient red blood cells in response to increases in endogenous erythropoietin that is sufficient to avoid perioperative allogeneic blood transfusion. In these patients pharmacologic doses of recombinant human erythropoietin (Epoetin alfa) have been shown to accelerate erythropoiesis, thereby increasing preoperative red blood cell production, hematocrit level, and hemoglobin concentration and reducing exposure to allogeneic blood transfusion. In four large multicenter studies, 869 patients undergoing major elective surgery were treated with a daily regimen (300 or 100 IU/kg x 14 or 15 doses) or a weekly regimen (600 IU/kg x 4 doses) of subcutaneous Epoetin alfa beginning either 2 or 3 weeks before surgery, respectively. Although all Epoetin alfa regimens were effective at accelerating erythropoiesis and increasing red blood cell production, the weekly regimen was the most patient friendly, cost effective regimen for treating preoperative anemia and minimizing patient risk of allogeneic blood transfusion. 相似文献
55.
Mojtaba Maleknejad Somayyeh Mohammadi Hamid Reza Naji Mehdi Hosseinzadeh 《International Journal of Electronics》2018,105(10):1753-1768
In this article, a low-power and energy-efficient hybrid full adder circuit is proposed, which is implemented based on multi-threshold NAND and NOR gates and transmission gate multiplexers. In order to implement this circuit, carbon nano tube field effect transistors are utilised. For evaluating the proposed design, comprehensive simulations are performed with regard to the most important aspects power, delay and power-delay product. The results are presented and displayed the superiority of the proposed cell in different voltage levels, load conditions, temperatures and robustness against process variations. 相似文献
56.
We report measurements of the wavelength dependence of the 3400-cm(-1) Raman scattering cross section of liquid water for excitation wavelengths between 215 and 550 nm. Using previous measurements of the absolute Raman scattering cross section, we have determined an expression for the wavelength dependence of the absolute Raman cross section for water. 相似文献
57.
Saeed Rasouli Heikalabad Mazaher Naji Asfestani Mehdi Hosseinzadeh 《The Journal of supercomputing》2018,74(5):1994-2005
Quantum-dot cellular automata (QCA) is the appearance of new technology and can be a suitable alternative to semiconductor transistor technology. In this paper, the new structure of the two-input XOR gate is presented, which is the modified version of the three-input XOR gate. This structure can be used to design various useful QCA circuits. By utilizing this gate, we design and implement a new full adder structure with 90-degree cells. This structure is designed in a single layer without cross-wiring. The operation of the proposed structure has been verified by QCADesigner version 2.0.3 and energy dissipation investigated by QCAPro tool. We also compared the effectiveness of our structure with the two previous structures. 相似文献
58.
Influence of electrolytes of Li salts,EMIMBF4, and mixed phases on electrochemical and physical properties of Nafion membrane
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Electrolyte‐soaked Nafion is commonly used as an ionic polymer in soft actuators. Here, a multitechnique investigation was applied to correlate the electrochemical behavior of Nafion membranes with their microstructures and nanostructures as a function of electrolyte type. The influence of electrolytes of Li salts with different counteranions on the Nafion membranes was investigated in terms of hydration level, structure (using X‐ray diffraction and small angle X‐ray scattering), stress–strain characteristics, and electrochemical behavior (by cyclic voltammetery and electrochemical impedance spectroscopy). The effects of using ionic liquid (IL), as the electrolyte, addition of different supporting solvent and the addition of Li+ ions to water‐free IL‐soaked membranes on the structural and electrochemical properties of Nafion were examined. The nano‐ and microstructure of the Nafion changed considerably as a function of the identity of the electrolyte solution. The electrochemical behavior of the IL‐soaked samples was compared with that of the water‐soaked Li+‐exchanged Nafion. It was seen that the ionic conductivity of the Nafion membranes was reduced significantly when water was replaced by pure IL. Using the supporting solvents increased the conductivity of IL‐soaked Nafion membranes dramatically. The presence of a small amount of Li+ ions together with the IL ions caused a significant decrease in charge transfer resistance and increases in double layer capacitance and in ionic conductivity over that of the water‐free sample and also over water‐soaked Li+‐exchanged Nafion. These findings can be useful to improve the knowledge on Nafion's microstructure and also to improve the electromechanical behavior of Nafion‐based ionic polymer–metal composites actuators. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45239. 相似文献
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M. Lakhal M. Bhihi H. Labrim A. Benyoussef S. Naji A. Belhaj B. Khalil M. Abdellaoui O. Mounkachi M. Loulidi A. El kenz 《International Journal of Hydrogen Energy》2013
In this work, we propose a model to investigate the hydrogen storage ab/desorption kinetic properties for the pure MgH2 using Kinetic Monte Carlo (KMC) simulations. To do such computations, the activation energies for different elementary processes have been estimated. Moreover, the different thermodynamical quantities of interest are determined by performing the ab-initio calculations. Then, we discuss the hydrogen diffusion in magnesium hydride (such as adsorption, diffusion and desorption). More precisely, we study the effect of each elementary mechanism on the diffusion that we characterize through the density distribution of hydrogen atoms including filling ratios, diffusion time, temperature and pressure. Among others, we show that all elementary mechanisms are needed to reproduce a behavior of ab/desorption which correlates well with the experimental results reported in literature. In particular, at high temperature and pressure, the results of simulations indicate that the studied material involves slow kinetics. 相似文献