Comparative Proteomics Based on 18O Labeling to Evaluate the Hepatotoxicity of Tris (2,3-dibromopropyl) Isocyanuratein Rats

Detecting protein expression levels in organisms exposed to environmental pollutants can help us understand the action mechanism of toxicity. In the present study, adult female Sprague-Dawley (SD) rats received a consecutive intraperitoneal injection of tris(2,3-dibromopropyl) isocyanurate (TBC) for seven days, and the ¹⁶O/¹⁸O labeling comparative proteomic approach was used to study the change of liver proteome in these rats. Thirty six differential proteins were identified between the control group and the high-dose-exposed group (8 mg/kg), of which, twenty eight proteins were down-regulated and eight proteins were up-regulated. Bioinformatics analysis revealed that most of the differential proteins were related with the metabolic and cellular processes. In addition, the contents of malondialdehyde (MDA), catalase (CAT), and glutathione (GSH) in liver were measured to evaluate the oxidative stress status induced by TBC exposure. Together, these findings showed that TBC might be toxic to liver by disrupting metabolic process and apoptosis. The results might provide a better insight into the mechanism of toxicity induced by TBC.     

不同浓度黄芪多糖在SH-SY5Y细胞内外抗氧化的研究

对不同浓度的黄芪多糖在SH-SY5Y细胞内外抗氧活性进行了研究,对其抗氧化清除自由基能力进行了评价。利用DPPH法检测其体外抗氧化作用,发现随着黄芪多糖浓度不断升高,其对自由基的清除率也不断的升高。用二氯荧光素检测方法（DCF）研究了黄芪多糖对细胞内活性氧自由基清除作用,然后用MTT检测其对H2O2损伤SH-SY5Y细胞活力的保护作用。发现黄芪多糖浓度越高,对胞内氧化自由基的清除率就越高,进一步的研究发现黄芪多糖浓度在75 mg/mL 对细胞预处理3 h,其对细胞的保护作用最佳。从细胞内、外两个水平说明黄芪多糖均有良好的抗氧化清除自由基活性的能力。     

New Cell Viability Measurement of SH-SY5Y Cells in the PD Research-Alamarblue~(TM)

The traditional MTT assay requires destructive analyses and is not convenient in continuous monitory of cell viability. However, a new cell model was developed in this research, by using the oxidation-reduction (redox) indicator alamarblue? instead of the MTT assay. The alamarblue?does no harm to cells and provide a much more safe and convenient methods of measurement. Firstly, cell apoptosis was induced by different concentration of 6-OHDA, then the cell viability was tested by the alamarblue?at a serial of time points. Finally, the optimism cells density, 6-OHDA concentration and testing time point were gained to set a wonderful SH-SY5Y cell model in our research. And when it is applied in the study of neuroprotection effects of NAC, GSH and Catalase, the new model reveals undeniable advantages.     

Effects of supersonic fine particle bombarding on thermal cyclic failure lifetime of thermal barrier coating

Thermal barrier coating ( TBC) consisting of a NiCoCrAlY bond coat ( BC) and a ZrO2-8 wt. % Y2O3 topcoat ( TC) was fabricated on the nickel-base superalloy by air plasma spray ( APS) . The BC was treated by supersonic fine particle bombarding ( SFPB) . Thermal cyclic failure and residual stress in thermally grown oxide ( TGO) scale were studied by SEM with EDS and ruby fluorescence spectroscopy ( RFS) . As shown in the results,after treated by SFPB,thickening of TGO was relatively slow,which reduced the level of growth stress. The TBC with SFPB treatment was still remained well undergoing 350 times of thermal cycle. However,after thermal cycle with the same times,the separation of TC was observed in TBC without SFPB treatment. The residual stress analysis by RFS showed that the residual stress of SFPB-treated TBC increased with the increasing number of thermal cycle. The residual stress of conventional TBC reached a value of 650 MPa at 350 times of cycle and that of SFPB-treated TBC only reached 532 MPa at 400 times of cycle. The BC with SFPB treatment after 400 times of cycle was analyzed by RFS,the high stress value was not observed in local thickened region of TGO. Thermal cycling resistance of TBC can be improved by the SFPB technology.     

改性超细炭黑诱发氧化应激的毒性效应与机理

为研究改性超细炭黑(modified ultrafine carbon black, MCB)诱发氧化应激的毒性效应与机理,将小鼠肝细胞和过氧化氢酶(catalase, CAT)暴露于不同质量浓度的MCB溶液中。采用CCK-8、丙二醛(malondialdehyde, MDA)含量和CAT活力检测等方法评价MCB的细胞毒性;利用荧光光谱,紫外-可见吸收光谱,圆二色谱等方法探究MCB对CAT构象的影响。结果表明:细胞活力随MCB质量浓度的升高而降低,低质量浓度的MCB(< 30 mg/L)刺激细胞提高CAT的活力来保护自身免受氧化损伤,高质量浓度的MCB(>30 mg/L)使MDA在细胞内累积并造成氧化还原失衡,造成肝脏的氧化损伤;光谱学研究发现, MCB会改变CAT的二、三级结构和氨基酸微环境,使肽链紧缩极性增强,骨架结构的变化降低了CAT的活性。阐明MCB造成氧化应激效应的毒性机理,同时为纳米材料的毒理研究提供了参考。     

改性超细炭黑诱发氧化应激的毒性效应与机理

为研究改性超细炭黑(modified ultrafine carbon black, MCB)诱发氧化应激的毒性效应与机理,将小鼠肝细胞和过氧化氢酶(catalase, CAT)暴露于不同质量浓度的MCB溶液中。采用CCK-8、丙二醛(malondialdehyde, MDA)含量和CAT活力检测等方法评价MCB的细胞毒性;利用荧光光谱,紫外-可见吸收光谱,圆二色谱等方法探究MCB对CAT构象的影响。结果表明:细胞活力随MCB质量浓度的升高而降低,低质量浓度的MCB(< 30 mg/L)刺激细胞提高CAT的活力来保护自身免受氧化损伤,高质量浓度的MCB(>30 mg/L)使MDA在细胞内累积并造成氧化还原失衡,造成肝脏的氧化损伤;光谱学研究发现, MCB会改变CAT的二、三级结构和氨基酸微环境,使肽链紧缩极性增强,骨架结构的变化降低了CAT的活性。阐明MCB造成氧化应激效应的毒性机理,同时为纳米材料的毒理研究提供了参考。     

热障涂层活塞热应力分析的格点型有限体积法

为研究热障涂层(thermal barrier coating,TBC)活塞热应力问题,将二维格点型有限体积法(cell vertex FVM,CVFVM)推广用于三维复合材料热力性能研究.利用交错网格技术,通过将物性参数和待解变量分别定义在单元中心和节点上,将物性参数的空间变化引入离散过程,从而避免数值不连续问题.采用CV-FVM数值模拟普通活塞热应力场,计算结果与ANSYS计算结果吻合良好.数值模拟TBC活塞热应力场,分析活塞TBC区域的热力性能,结果表明:活塞的最大温度位于燃烧室与活塞顶面的交界区域;应力最大值位于粘结层与陶瓷层的分界面附近;周向应力对活塞的整体应力水平起主要影响.数值结果表明CV-FVM能够作为TBC活塞热力性能研究的数值预测工具.     

三种启动子shRNA表达框的制备及其在筛选有效SiRNA中的应用

为能快速经济地获取小干扰核糖核酸 (small interfering RNA siRNA)，设计采用特异性延伸引
物和上游、下游两条通用引物，通过重叠延伸一步聚合酶链反应(PCR)法一次性快速、简捷地制备包含U6
+1、H1或tRNAVal在内的三种人小RNA多聚酶III启动子 小发夹状RNA（shRNA）表达框.用该方法制备的增
强型绿色荧光蛋白（EGFP）特异性三种启动子 shRNA表达框在转染HepG2细胞后有效地抑制了EGFP转基因
表达，其中以tRNAVal shRNA表达框抑制效果最显著，且未检测到干扰素应答基因2'5'OAS mRNA的表达，
表明该表达框可被有效转染并启动产生特异基因的RNA干扰效应，进而用于快速筛选最佳siRNA位点及其最
适搭配启动子.     

关于基体曲率的热障涂层残余应力分析

采用空心和实心四相同心圆模型,导出了轴对称温度应力状态下的位移公式,分析了基体曲率对热障涂层残余应力的影响。结果表明:热障涂层结构中各层内既有环向应力,又有径向应力,应力大小与温降成线性关系;当陶瓷层在外层时,在氧化层/陶瓷层和粘结层/氧化层界面上产生垂直界面的拉应力,且实心模型的拉应力远大于空心模型的拉应力;当陶瓷层在里层时,空心模型中相应界面上的应力为压应力。     

能量限制抑制安妥明所致小鼠肝脏氧化损伤

对小鼠进行了短时间(10个月)的能量限制,考察了能量限制对安妥明所致小鼠肝脏氧化损伤的影响。实验发现,10个月的能量限制未能改善小鼠肝脏中产生的氧化损伤,但能完全消除安妥明所导致的8-OHdG和羰基蛋白增加。通过实验结果表明,10个月的能量限制能够提高组织对安妥明所引起的氧化损伤的抵抗作用。     

逆境诱导烟草悬浮细胞内处理小体的形成

指出处理小体( processing body,P-body)在真核细胞基因表达调节过程中,特别是在逆境条件下,能为mRNA在细胞质内转运提供储存和降解场所.研究通过农杆菌转化法成功将含有处理小体荧光标记物-脱帽酶1( decapping enzyme,DCP1)与青色荧光蛋白(cyan fluorescent protein,CFP)融合蛋白基因的植物表达载体转入烟草悬浮细胞.利用激光共聚焦显微镜观察到在高温和盐胁迫下,处理小体的数量和体积都有增加.通过蔗糖密度梯度离心分析逆境条件下多核糖体的变化,发现在高温和盐胁迫下,多核糖体解体,呈现翻译抑制特征.     

利用开口矩形波导探头进行热障涂层微波检测的参数优化设计

利用CST微波工作室(computer simulation technology microwave studio)仿真研究用矩形波导作为探头检测热障涂层厚度的可行性,并对波导探头进行仿真计算,分析提离距离对反射系数幅值和相位差的影响.结果表明,在特定的提离距离时利用反射系数的幅值和相位差都可良好地表征涂层的厚度。     

预应力混凝土Y型桥墩强震下耗能机理分析

针对强震下预应力混凝土Y型桥墩的损伤问题,以某市二环路改造工程预应力混凝土Y型桥墩为研究对象,提出了该桥墩的损伤变形及耗能机理,并对其进行了分析.结果表明:强震下Y型桥墩变截面处会出现过多的应力集中,从而导致U形槽区域率先发生损伤,并致使墩柱内力重分布;轴压力的增加会加快墩柱的塑性变形,残余应变增大;横桥向会吸收较多的地震能量,但不能承受过多的位移变化;加固Y型桥墩的U形槽区域,减少桥墩的配重,增加桥墩截面刚度和强度可以有效地提高Y型桥墩的抗震能力.     

茶氨酸对酒精诱导人肝HL7702细胞损伤的保护作用及机理

目的探究茶氨酸在酒精诱导人肝HL7702细胞损伤方面的保护作用及机理。方法选取500~1 000 mmol范围内,梯度设置为100 mmol的6个酒精浓度处理组对HL7702细胞进行初步处理,选择不同浓度茶氨酸培养HL7702细胞,MTT法测定细胞的存活率以确定酒精造模浓度和茶氨酸最适浓度范围。以不同浓度茶氨酸预保护模型浓度酒精处理过的细胞,测定细胞的存活率,检测其过氧化氢（H₂O₂）、丙二醛（MDA）、超氧化物歧化酶活性（SOD）、谷胱甘肽过氧化物酶（GSH-PX）及总抗氧化能力（T-AOC）的含量。结果初步确定酒精造模浓度为800 mmol;茶氨酸浓度在2 000 μg/mL以下对HL7702细胞无毒性,结合实际情况将茶氨酸给药浓度调整为200~800 μg/mL;与模型组相比,茶氨酸显著提高了酒精损伤模型中HL7702的存活率,对HL7702细胞内H₂O₂和MDA的生成起到了一定的抑制作用,而SOD、GSH-PX活性升高,T-AOC能力也增加。结论茶氨酸在不同方面均被证明对酒精诱导人正常肝细胞氧化损伤具有保护作用。其作用机理是茶氨酸通过抑制酒精刺激下抗氧化关键酶活性的降低及氧化反应中间产物的产生,避免人正常肝细胞在酒精诱导下发生氧化损伤及氧化应激反应。     

陶瓷热障涂层在石油化工行业中的应用

热障涂层（TBC）是一种陶瓷涂层,它沉积于耐高温金属或超合金表面,用于保护基底材料,使得用其制成的设备部件能在高温下运行。热障涂层能够阻止外部环境的热量向基体金属传递,提高基体的工作温度,并达到隔热、抗氧化、防腐蚀的目的。石油化工行业有许多操作温度很高的设备,在这些设备的高温部件应用热障涂层,不仅可以使设备的制造成本降低、生产效率提高,而且设备庞大的体积也将相应的减小。     

高能饮食与氧化应激

随着生活水平的提高,城乡居民的膳食结构发生了巨大变化,膳食中油脂和糖的比例不断增多。能量摄入的增加,体内能量代谢旺盛,其副产物活性氧也随之增加,可诱发机体氧化应激。氧化应激又是许多疾病发病过程中共同的作用机制,如：代谢综合征等。从能量代谢诱发氧化应激、活性氧对机体损伤作用、活性氧对信号通路调节等方面来阐述高能膳食性氧化应激在相关疾病中的作用以及防治策略。     

Anti-hypertensive effects of rosiglitazone on renovascular hypertensive rats: role of oxidative stress and lipid metabolism

This study investigated the anti-hypertensive mechanism of rosiglitazone in renovascular hypertensive rats, and examined its relationship to oxidative stress and lipid metabolism. The renovascular hypertension was induced by stenosis of the left renal artery. Four groups of rats were selected: control, induced untreated, rosiglitazone (20.mg/kg) and captopril (10.mg/kg). After 14.d of administration, compared with induced untreated group, rosiglitazone group reduced the renovascular hypertensive rats' systolic blood pressure and diastolic blood pressure, and decreased total cholesterol (TCH), triglyceride (TG), angiotensin II (Ang II) and angiotensin receptor (AT₁) levels(P<0.05). Meanwhile, rosiglitazone remarkably decreased the levels of malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) while improved the levels of supperoxide dismutase (SOD) and reduced glutathione (GSH). These results suggested that rosiglitazone could effectively decreased the blood pressure in renovascular hypertensive rats, and this might be performed by regulating the activity of angiotensin and the lipid metabolism and improving the oxidative stress.     

Effect of TBC plasticization on thin polycarbonate sheet

Tributyl citrate （TBC） plasticizer has been selected to prepare the novel plasticized PC under different time and temperature. The TBC plasticization effect on PC T, mechanical properties and morphology has been investigated by DMTA, DSC, tensile test and SEM. The results show that the TBC content in PC is controlled by plasticization time and temperature. The mass-loss test has conftnned a less lost rate of TBC in PC. The T declines gradually with increasing TBC content. The tensile modulus and strength of the plasticized PC also decrease with the increase of TBC content, and an approximate linear relationship is found to exist between the TBC content and the tensile modulus and strength. The SEM images show that significant changes have taken place on the surface and in the cross-section of plasticized thin PC sheet.     

随焊冲击碾压控制平面封闭焊缝残余变形研究

随焊冲击碾压是一种控制平面封闭焊缝残余应力变形及防止热裂纹的新方法,它通过2个冲击碾压轮迫使焊缝金属沿着一定的方向严生塑性变形流动,达到减小应力变形防止热裂纹的产生．试验结果证明随焊冲击碾压试件表面平整光滑,没有热裂纹．在一定的范围内,试件的最大残余变形量与气锤压力之间有一定的对应关系;在合适的气锤压力下,随焊冲击碾压法可以将薄壁构件平面封闭焊缝引起的残余变形降低到常规焊接状态的1／12以下．由于随焊冲击碾压能够将焊缝外侧周向压应力降低到结构的临界失稳压应力以下,因而减小了薄壁构件失稳变形,同时还减小了由焊缝收缩引起的焊接变形．     

Y3+取代Bi3+对Bi2(Zn1/3Nb2/3)2O7陶瓷烧结温度的影响

采用固相反应制备Bi2(Zn1/3Nb2/3)2O7微波陶瓷,并借助X射线、扫描电镜、LCR4284测试仪,研究Y3 取代Bi3 对Bi2(Zn1/3Nb2/3)2O7陶瓷烧结特性及介电性能的影响。研究结果表明:随着Y3 替代量的增加,晶粒尺寸减小,介电常数先减小后增大,烧结温度升高;适量的Y3 替代可以获得性能很好的BZN介质材料。