莱菔硫烷诱导人肝癌HepG -2细胞凋亡的JNK途径

探讨莱菔硫烷(sulforaphane,SFN)诱导人肝癌HepG -2细胞凋亡过程中,JNK途径的作用.采用荧光显微镜观察凋亡细胞形态;采用Western Blot法检测人肝癌HepG -2细胞内JNK和p- JNK 蛋白的表达.结果表明,10、20、40 μmol/L的SFN作用人肝癌HepG -2细胞48 h后,...     

TGF-β1与EGF对肺泡Ⅱ型上皮细胞表型及功能的影响

目的:探讨TGF-β1与EGF对肺泡Ⅱ型上皮细胞(RLE-6TN)的影响。方法:将细胞分成对照(C)、TGF-β1(T)、EGF(E)及TGF-β1+EGF(TE)组。采用相差显微镜观察细胞形态,免疫荧光检测α-SMA表达,W.B检测上皮、间质细胞标记物、MMPs及信号蛋白的表达;流式细胞术检测凋亡情况。结果:T及TE组RLE-6TN发生EMT转变并见间质标记物及MT1-MMP、MMP2表达上调,E组Vimentin、MT1-MMP、MMP2及CD147表达上调;T与E组p-ERK、p-38MAPK及p-Akt表达上调,T组p-Smad2表达上调;T与E组均见凋亡,TE组凋亡加剧。结论:单用EGF不能诱导RLE-6TN发生EMT,合用TGF-β1无协同诱导EMT,却能协同诱导凋亡。TGF-β1诱导EMT时,主要通过EGFR信号通路诱导MMPs表达。     

Th17细胞调节宿主免疫应答功能研究进展

T细胞诱导的特异性免疫应答是机体血液淋巴细胞特异性免疫应答的重要组成部分,Th17细胞作为第3类因子可区分于体液中其他辅助T细胞.基于此,论述了Th17细胞系在对抗胞外寄生和胞内寄生细菌以及真菌感染中的作用.一系列研究表明,Th17细胞系能够紧密联系固有免疫和特异性免疫,使机体产生强烈的感染炎症反应.Th17细胞系既能...     

等离子体处理影响有机光伏电池阳极表面性能的研究

采用等离子体处理对有机光伏电池阳极表面进行改性,通过X射线光电子能谱、X射线衍射、分光光度计和四探针等测试技术,研究了改性处理对阳极表面性能的影响.结果表明:等离子体优化了表面化学组分,降低了方块电阻.另外,利用处理前后的阳极样品制备了双层结构器件,通过分析其电流-电压特性,进一步研究了改性对其功函数的影响.研究结果表明,阳极改性对改善有机光伏电池的器件性能具有重要作用.     

Topography,structure, and formation kinetic mechanism of carbon deposited onto nickel in the temperature range from 400 to 850℃

The carbon deposition behavior on nickel particles was observed within the temperature range from 400 to 800℃ in a pure methane atmosphere.The topography,properties,and molecular structure of the deposited carbon were investigated using field-emission scanning electron microscopy (FESEM),temperature-programmed oxidation (TPO) technology,X-ray diffraction (XRD),and Raman spectroscopy.The deposited carbon is present in the form of a film at 400-450℃,as fibers at 500-600℃,and as particles at 650-800℃.In addition,the structure of the deposited carbon becomes more ordered at higher temperatures because both the TPO peak temperature of deposited carbon and the Raman shift of the G band increase with the increase in experimental temperature,whereas the intensity ratio between the D bands and the G band decreases.An interesting observation is that the carbon deposition rate is suppressed in the medium-temperature range (M-T range) and the corresponding kinetic mechanism changes.Correspondingly,the FWHM of the G and D1 bands in the Raman spectrum reaches a maximum and the intensities of the D2,D3,and D4 bands decrease to low limits in the M-T range.These results indicate that carbon structure parameters exhibit two different tendencies with respect to varying temperature.Both of the two group parameters change dramatically as a peak function with increasing reaction temperature within the M-T range.     

前界面缺陷对钙钛矿太阳电池性能的影响模拟

通过对光伏器件的模拟分析可以进一步提高对器件的认识深度,在实际工艺中利于优化器件制备条件,为高效钙钛矿太阳电池提供新思路.借助SCAPS模拟软件研究钙钛矿电池中钙钛矿吸收层、CH_3NH_3PbI_(3-x)Cl_x/TiO_2界面、TCO/TiO_2界面中缺陷态密度对电池性能的影响,模拟表明CH_3NH_3P I_(3-x)Cl_x中缺陷态密度和缺陷能级位置对器件效率的影响非常大,当缺陷态密度小于10~(16)cm~(-3)时,器件光电转换效率都能保持较高数值,达到16%以上.CH_3NH_3PbI_(3-x)Cl_x/TiO_2界面层中CH_3NH_3PbI_(3-x)Cl_x缺陷态密度对器件的FF影响较大,当缺陷态密度小于10~(17)cm~(-3)时器件填充因子都能保持较高的数值,达到78%以上.TiO_2缺陷态密度降低和掺杂浓度提高对器件填充因子和开路电压都有利.TCO/TiO_2界面层中适当增大窗口层掺杂浓度和带隙可以有效改善器件的光伏性能.     

HMOX1在低氧条件下对胶质瘤干细胞的作用

HMOX1(Heme Oxygenase 1)属于血红素加氧酶家族,作为血红素分解代谢中的必须酶,在恶性胶质瘤中高表达。脑胶质瘤干细胞(Glioma Stem Cell,GSC)是胶质瘤中的一小群肿瘤细胞,具有无限增殖、自我更新、多向分化的能力,被认为是肿瘤发生、复发、转移的根源。本实验通过质谱筛选,发现HMOX1特异性在胶质瘤干细胞中被低氧诱导高表达。目前关于HMOX1蛋白与缺氧环境下GSC的功能相关性未见文献报道。为了研究HMOX1是否在低氧时对GSC有调控作用,我们用慢病毒感染体系在GSC中敲低HMOX1表达,接着对细胞进行1%O_2低氧培养,用Western Blot检测基因干涉效果,用Tumor Sphere形成实验观察GSC细胞表型。实验结果表明,在低氧条件下干涉GSC中HMOX1基因的表达对GSC的生长及存活有明显的抑制。综上所述,HMOX1在GSC中特异性被低氧诱导高表达,且对GSC的生长存活具有调控作用,提示HMOX1有可能是GSC在低氧微环境中的重要调控因子。     

Th2CysPrx基因提高酿酒酵母多种胁迫耐受性研究

【目的】过氧化还原蛋白是生物体调节体内氧化还原系统的一种重要蛋白质,在植物生长代谢中起重要作用。前期研究发现过表达刚毛柽柳Th2CysPrx基因的烟草和柽柳中4种抗氧化酶基因(ThGSTZ1、ThGPX、ThSOD和ThPOD)的表达水平上调, 转基因植株的NaCl胁迫耐受性提高。本实验探究Th2CysPrx基因除了响应NaCl胁迫应答,是否还参与其他盐胁迫和其他胁迫的应答。 【方法】将Th2CysPrx构建到pYES2酵母表达载体上,转化到酿酒酵母INVSC1细胞中,分析比较重组酵母(pYES2-Th2CysPrx)和对照酵母(pYES2)细胞在各种非生物胁迫后的生长情况。【结果】过表达Th2CysPrx基因的重组酵母细胞在低温、KCl和LiCl胁迫后存活率与对照相比差异不显著;但H₂O₂、NaCl或NaHCO₃胁迫后酵母细胞的存活率显著提高。此外,高于0.5 mol/L山梨醇或高温(达到44 ℃),或低于质量分数0.007% CdCl₂胁迫后,过表达Th2CysPrx基因能显著提高重组酵母的细胞存活率。【结论】Th2CysPrx基因可以显著增强酵母细胞对NaCl和NaHCO₃胁迫的耐受能力,以及特定的渗透胁迫、高温胁迫、氧化胁迫和重金属胁迫的耐受能力,但对低温、KCl和LiCl胁迫耐受能力无明显影响。     

Fabrication and biological evaluation of polyether ether ketone(PEEK)/bioceramic composites

The repair of vascularized bone defects represents a significantly clinical challenge, and vascular regeneration is one of the necessary factors to promote bone tissue regeneration. To effectively repair large bone defects, new bone tissue must regenerate with a rich vascular network. Therefore, the development of biomaterials that can promote the regeneration of vascularized bone tissue is currently receiving attention from researchers. In this study, Li–Ca–Si bioceramics (LCS) containing Li, Ca, and Si elements was developed, then LCS was compounded with PEEK to prepare PEEK+10% LCS, PEEK+20% LCS, PEEK+30% LCS, and the effect of LCS-PEEK composite biomaterials on the proliferation and angiogenic ability of human umbilical vascular endothelial cells (HUVECs) further explored by Cell Counting Kit-8 (CCK-8), scanning electron microscope (SEM), quantitative real-time PCR (QPCR), Western Blotting and enzyme linked immunosorbent assay (ELISA). The results showed that HUVECs inoculated on 30%LCS ?+ ?PEEK material exhibited the best proliferation ability. And the adhesion ability of endothelial cells on PEEK gradually increased with the increase of LCS contents. Furthermore, the angiogenic ability of HUVECs on LCS-PEEK composites was examined using QPCR and Western blotting, and the results showed that the expression of angiogenic-related genes and proteins of HUVECs on PEEK composites gradually increased with increasing LCS concentration. These results demonstrated that the angiogenic ability of HUVECs was effectively stimulated by LCS-modified PEEK materials. The present results indicate that the PEEK material can be modified with bioceramics to promote angiogenesis, and this study lay the foundation for the subsequent development of scaffolds that promote vascularized bone tissue regeneration.     

喷施草甘膦对大豆表皮细胞超微结构影响的研究

以抗草甘膦大豆及东农42为试验材料,对抗草甘膦大豆和东农42施用草甘膦,从表皮细胞的形态结构来研究草甘膦对抗草甘膦大豆和东农42的不同作用.试验结果如下:抗草甘膦大豆在喷施草甘膦后,表皮细胞、气孔在喷施草甘膦后有一定的变形,到喷施后3～5 d开始逐渐恢复.东农42与抗草甘膦大豆明显不同,表皮细胞、气孔都随着天数的增加变形程度加大.通过统计上表皮的开口气孔数,结果表明气扎数首先出现与对照的偏离,之后抗草甘膦大豆逐渐与对照相接近,而东农42的变化逐渐偏离对照.