体外沉默Rce1对舌鳞状细胞癌细胞侵袭和迁移能力的影响

目的通过RNA干扰技术沉默Rce1基因,探讨Rce1对舌癌细胞侵袭和迁移能力的影响。方法体外培养舌鳞状细胞癌Cal-27和SCC-4细胞,设计合成Rce1基因的小干扰RNA(si RNA),采用脂质体载体瞬时转染沉默Rce1基因。根据转染的si RNA不同,将实验组分为Rce1-si RNA-1组、Rce1-si RNA-2组、Rce1-si RNA-3组,脂质体载体分别转染相对应序列的si RNA。脂质体转染si CON作为阴性对照组,不转染si RNA作为空白对照组。采用实时定量聚合酶链反应检测各组Rce1、Rho A以及K-Ras基因的表达,蛋白质印迹法(Western blot)检测Rce1、Rho A、K-Ras、金属基质蛋白酶(MMP)-2及MMP-9的表达,采用体外侵袭实验检测Cal-27和SCC-4的侵袭能力,细胞划痕实验检测细胞迁移能力。结果实时定量聚合酶链反应及Western blot检测结果显示,与阴性对照组和空白对照组相比,实验组的Rce1基因及蛋白表达均下调(P<0.05),Rho A、K-Ras基因及蛋白表达无统计学差异(P>0.05),MMP-2、MMP-9表达下降(P<0.05)。体外侵袭实验表明,与对照组相比,实验组在聚碳酯膜上的细胞总数明显减少(P<0.05)。细胞划痕实验表明,实验组划痕处细胞闭合时间明显长于对照组(P<0.05)。结论体外沉默Rce1可以有效下调其在舌癌细胞Cal-27和SCC-4中的表达水平,降低迁移和侵袭能力。

HER-2/neu基因在结肠癌组织中的表达及其临床意义(英文)

Objective: The article aims to detect the expression of HER-2/neu gene in colon cancer tissues and adjacent tissues, to analyze the relationship between different pathologic types and clinical features, also to invest the distribution of patients with positive expression of HER-2 gene. Methods: The expression of HER-2 gene in the 223 samples with colon cancer was detected by immunochemical approach. The expression of HER-2 gene in colon cancer tissues and adjacent tissues and different pathologic types was analyzed by χ2test. The correlation between the expression of HER-2 gene and clinical features was analyzed by Spearman. Results: The number of positive expression of HER-2 gene in colon cancer tissues and adjacent tissues were 74 and 0 respectively, the difference has statistical significance. The number of papillary or tubular adenocarcinoma was 182, among them, 60 cases were positive expression. The number of mucinous adenocarcinoma was41, among them, 14 cases were positive expression. The expression of HER-2/neu gene has no correlation with sex, age, the maximum diameter, general classification, degree of differentiation and depth of invasion, which has no statistical significance.However, the expression of HER-2/neu gene has correlation with metastasis of lymph node and Dukes stage, which has statistical significance. The expression of HER-2/neu gene was positive correlation with metastasis of lymph node and Dukes stage. The correlated coefficient index was 0.320 and 0.320 respectively. In the 74 patients with positive expression of HER-2gene, 59.4% of them were 60-74 years old. And there was 97.3% of the patients without family history of adenocarcinoma.Conclusion: The expression of HER-2/neu gene in colon cancer tissues was higher than in adjacent tissues. The expression of HER-2/neu gene has no correlation with sex, age, the maximum diameter, general classification, degree of differentiation and depth of invasion, but has correlation with metastasis of lymph node and Dukes stage. The expression of HER-2/neu gene was positive correlation with metastasis of lymph node and Dukes stage. The expression of HER-2/neu gene with age of 60-74 years old and without family history of adenocarcinoma was higher than other groups.

Fabrication of Anti-reflecting Si Nano-structures with Low Aspect Ratio by Nano-sphere Lithography Technique

Nano-structured photon management is currently an interesting topic since it can enhance the optical absorption and reduce the surface reflection which will improve the performance of many kinds of optoelectronic devices, such as Si-based solar cells and light emitting diodes. Here, we report the fabrication of periodically nano-patterned Si structures by using polystyrene nano-sphere lithography technique. By changing the diameter of nano-spheres and the dry etching parameters, such as etching time and etching power, the morphologies of formed Si nano-structures can be well controlled as revealed by atomic force microscopy.A good broadband antireflection property has been achieved for the formed periodically nano-patterned Si structures though they have the low aspect ratio(<0.53). The reflection can be significantly reduced compared with that of flat Si substrate in a wavelength range from 400 nm to 1200 nm. The weighted mean reflection under the AM1.5 solar spectrum irradiation can be as low as 3.92% and the corresponding optical absorption is significantly improved, which indicates that the present Si periodic nano-structures can be used in Si-based thin film solar cells.

Effect of rare-earth doping on adsorption of carbon atom on ferrum surface and in ferrum subsurface:A first-principles study

The adsorption of carbon atom on Fe surface and in Fe subsurface with and without rare earth(La and Ce)substitution in the surface layer and subsurface layer was studied by first-principles calculations.The carbon atom is predicted to adsorb at hollow and long bridge site on Fe(100)and Fe(110),respectively.However,the carbon atom shifts to occupy preferentially hollow site on both Fe(100)and Fe(110)with rare earth atom doping at surface layer.The lower adsorption energies involved with stronger adsorption abilities were obtained for carbon atoms on Fe surface with rare earth doping at surface layer,which was determined by the electronic structure of the surface atoms.The La atom was pulled out the surface after carbon adsorption due to strong interaction of La-C,which is consistent with the more charge transfer.In the subsurface region,the carbon atom prefers to occupy at octahedral site with rare earth doping at surface layer in Fe slab.These strong adsorption energies of the carbon atoms on Fe surface and in Fe subsurface with rare earth pose relevant insights into the interaction between carbon and rare earth,which helps to understanding the influence mechanism of rare earth in carburizing.

Microstructure,oxidation behavior and tribological properties of AlCrN/Cu coatings deposited by a hybrid PVD technique

Achieving high hardness and low friction at elevated temperatures for nitride-based hard coatings has substantial scientific interest and application significance.In this study,AlCrN/Cu coatings were deposited by a hybrid PVD technique combining arc evaporation from an Al_(60)Cr_(40) target and magnetron sputtering from a Cu target in a mixed Ar and N_(2) atmosphere.The microstructure,oxidation behavior,and tribological properties of the coatings were investigated.AlCrN/Cu coatings show a dual-phase structure of(Al,Cr)N solid solution and Cu metallic phase.Excessive sputtering power of the Cu target induces the disintegration of interlayer interfaces of the nano-multilayered geometry,accompanied by a decline in hardness from above 30 GPa to 22.7 GPa.Moreover,the formation of fine CuO grains on the coating surface is conducive to reducing the friction coefficient of AlCrN/Cu when exposed to air at high temperatures.The AlCrN/Cu coating with a sputtering power of 0.5 kW obtains a friction coefficient of 0.39±0.05 after pre-oxidation at 800℃,distinctly lower than that of AlCrN,which exhibits a friction coefficient of~0.65.The further transformation of CuO to cubic Cu(Al,Cr)_(2)O_(4),which stems from the solid-state reaction of CuO,Al_(2)O_(3),and Cr_(2)O_(3),would cause a rise in friction coefficient and wear loss.The mechanism of oxidation and tribological behavior of the AlCrN/Cu coatings related to the temperature and Cu content was discussed.