The progress of olfactory transduction and biomimetic olfactory-based biosensors

Olfaction is a very important sensation for all animals. Recently great progress has been made in the research of olfactory transduction. Especially the novel finding of the gene superfamily encoding olfactory receptors has led to rapid advances in olfactory transduction. These advances also promoted the research of biomimetic olfactory-based biosensors and some obvious achievements have been obtained due to their potential commercial prospects and promising industrial applications. This paper briefly introduces the biological basis of olfaction, summarizes the progress of olfactory signal transduction in the olfactory neuron, the olfactory bulb and the olfactory cortex, outlines the latest devel- opments and applications of biomimetic olfactory-based biosensors. Finally, the olfactory biosensor based on light addressable potentiometric sensor (LAPS) is addressed in detail based on our recent work and the research trends of olfactory biosensors in future are discussed.     

基于石墨烯-金纳米粒子复合材料的DNA生物传感器

以柠檬酸钠为还原剂和稳定剂制备石墨烯 金纳米粒子复合材料, 复合材料被柠檬酸钠羧基化后与末端氨基修饰的DNA发生键合, 制备DNA探针, 并以蒽醌-2-磺酸钠（AQMS）为杂交指示剂检测DNA序列的特异性. 结果表明: 基于石墨烯-金纳米粒子修饰的DNA传感器可选择性区分单碱基错配的目标DNA序列; 该传感器具有较高的特异选择性.     

Optical detection of acetylcholine esterase based on CdTe quantum dots

In this study, we have constructed a simple, sensitive and rapid biosensor for detection of acetylcholine esterase (AChE) based on CdTe quantum dots (QDs). The detection limit of AChE by one-step enzyme reaction based on the thiolglycolic acid (TGA) stabilized QDs (TGA-QDs) was 10 U/L and the linear range was 10-100 and 100-1200 U/L, respectively. The detection limit of AChE by two-step enzyme reaction based on the 3-mercaptopropionic acid (MGA) stabilized QDs (MGA-QDs) was found to be 20 U/L and the linear range was 100-2500 U/L. The experimental conditions of biosensors were optimized, and the detection mechanism was studied. We also detected AChE in serum samples based on TGA-QDs or MGA-QDs. The linear range was 10-140 and 50-1000 U/L, respectively. The excellent performance of this novel biosensor demonstrated that this strategy has prodigious potential to be applied in practice detection of AChE.     

ICBP90介导PI3K/AKT通路阻断剂LY294002抑制Jurkat T细胞增殖

目的:探讨磷脂酰肌醇3激酶/丝氨酸苏氨酸蛋白激酶B(PI3K/AKT)信号通路特异性抑制剂LY294002在JurkatT细胞增殖中的作用.方法:以急性T细胞白血病胞(Jurkat T 细胞)为模型,PD98059和阿霉素为阳性对照,在倒置显微镜下观察LY294002对Jurkat T细胞的集落形成的影响,四甲基偶氮唑蓝(MTT)检测LY294002处理后Jurkat T细胞的增殖,流式细胞术检测LY294002处理后Jurkat T细胞周期的变化,Western blotting方法检测Jurkat T细胞中ICBP90蛋白的表达以确定其与LY294002抑制Jurkat T细胞增殖的关系.结果:LY294002能够显著抑制Jurkat T细胞的集落形成和增殖,使Jurkat T细胞停滞于G2/M 期,导致Jurkat T细胞ICBP90蛋白的表达显著降低,LY294002与阿霉素联合用药可产生一定的协同效应. 结论:LY294002通过下调Jur-katT细胞ICBP90蛋白的表达,抑制Jurkat T细胞增殖.     

桂枝茯苓丸调控MTDH和PTEN逆转卵巢癌多药耐药的机制研究

研究桂枝茯苓丸在人卵巢癌耐药性裸鼠肿瘤模型中对凋亡的诱导作用,探讨其可能的作用机制。采用实时无标记细胞分析系统检测SKOV3/DDP对顺铂和紫杉醇的耐药性,建立SKOV3/DDP卵巢癌耐药性BALB/c裸鼠肿瘤模型,模型裸鼠随机分为桂枝茯苓丸浓缩液16 g.kg-1.d-1(高)、8 g.kg-1.d-1(中)、4 g.kg-1.d-1(低)剂量组、PI3K抑制剂LY294002组、低剂量桂枝茯苓丸LY294002组(联用组)及对照组,给药10天后剖取肿瘤组织,采用流式细胞术检测肿瘤细胞的凋亡率,采用荧光定量PCR检测肿瘤组织中MTDH、PTEN mRNA的相对表达。结果表明,SKOV3/DDP细胞对顺铂和紫杉醇的耐药倍数分别为4.57和4.36倍。随着桂枝茯苓丸浓缩液剂量的增加,肿瘤细胞的凋亡率逐渐增加,上调PTEN mRNA和下调MTDH mRNA的作用逐渐增强,各组之间差异具有显著性(P < 0.01)。LY294002和低剂量桂枝茯苓丸联用后,抑制凋亡的作用强于二者分别单用的凋亡抑制作用,下调MTDH mRNA和上调PTEN mRNA的作用强于其他各组(P < 0.01)。说明在SKOV3/DDP卵巢癌耐药性BALB/c裸鼠模型中,桂枝茯苓丸能够剂量依赖性地诱导耐药性肿瘤细胞的凋亡,其机制可能与上调PTEN mRNA和下调MTDH mRNA有关。     

PKB negatively modulates TGF-β responsiveness in prostate carcinoma PC-3 cells through its interaction with Smad3

Transforming growth factor-β (TGF-β) is a multi- functional growth regulator belonging to the TGF-β superfamily consisting of TGF-β, activin, bone mor- phological proteins and other factors. It regulates many aspects of cellular behavior, including mi…     

无机介孔材料在第三代电化学生物传感器中的应用研究

无机介孔材料是一种孔直径在2,50nm的多孔材料。这种材料具有结构规则,机械性能高、化学和热能稳定性好等特点。近年来,随着材料合成技术的提高,不断有新型高负载能力和生物相容性好的介孔材料被开发出来。同时,实验表明,无机介孔材料是固载生物大分子的良好载体。利用无机介孔材料固载氧化还原蛋白质并结合其的直接电子转移,为我们提供了一种新的构建第三代生物传感器的方法。基于无机介孔材料的特点及氧化还原蛋白质的直接电子转移,所构建的第三代电化学生物传感器有望具有较传统电化学传感器更好的性能。将介孔材料分为二氧化硅基和非二氧化硅基2大类,描述了无机介孔材料在第三代电化学生物传感器中的应用。     

Optimal design of label-free silicon“ lab on a chip” biosensors

This paper reported the optimal design of label-free silicon on insulator(SOI) "lab on a chip"biosensors.These devices are designed on the basis of the evanescent field detection principles and interferometer technologies.The well-established silicon device process technology can be applied to fabricate and test these biosensor devices.In addition,these devices can be monolithically integrated with CMOS electronics and microfuidics.For these biosensor devices,multi-mode interferometer(MMI) was employed to combine many stand-alone biosensors to form chip-level biosensor arrays,which enable realtime and label-free monitoring and parallel detection of various analytes in multiple test samples.This sensing and detection technology features the highest detection sensitivity,which can detect analytes at extremely low concentrations instantaneously.This research can lead to innovative commercial development of the new generation of high sensitivity biosensors for a wide range of applications in many fields,such as environmental monitoring,food security control,medical and biological applications.     

An effective amperometric biosensor based on graphene modified gold nanowire arrays for glucose detection

A novel glucose biosensor based on graphene nanosheets （GNs） modified gold nanowire arrays （AuN- WAs） electrode was constructed. Highly ordered gold nanowire arrays were prepared by direct electrodeposition in anodic aluminum oxide templates. GNs were synthe- sized through a public route involving graphite oxidation, exfoliation, and chemical reduction. Field emission scan- ning electron microscope and high-resolution transmission electron microscope were employed to characterize the as- prepared AuNWAs and GNs. Glucose oxidase was immobilized on the surface of GNs-AuNWAs modified electrode via a cross-linking method. The cyclic voltam- metry results showed that the GNs-AuNWAs-based glu- cose biosensors have high catalysis activity to hydrogen peroxide （H2O2） than those modified with GNs or AuN- WAs only. Furthermore, amperometric response was employed to detect glucose concentration owing to its simplicity, high selectivity, and relative low cost. Glucose biosensors based on GNs-AuNWAs showed excellent performance with high sen- sitivity of 40.25 μA cm^-2 （mmol/L）^-1, low detection limit of 0.02 mmol/L, and a linear range from 0.02 to 3 mmol/L.     

氧化石墨烯对DNA荧光分子探针FRET效应的研究

研究了氧化石墨烯的浓度、氧化石墨烯与DNA分子荧光探针的反应温度、DNA链长度对FRET效应的影响.研究表明,氧化石墨烯的浓度、氧化石墨烯与DNA分子荧光探针的反应温度、DNA链长度对FRET效应都有着重要的影响.氧化石墨烯浓度越大,其对DNA分子探针的荧光猝灭效率越高;氧化石墨烯与DNA分子荧光探针的反应温度越高,淬灭效率越高;DNA链越长,氧化石墨烯淬灭的效率越低.因此,氧化石墨烯的浓度、氧化石墨烯与DNA分子荧光探针的反应温度、DNA链长度对FRET效应都应该是设计生物传感器时考虑的因素.     

现代生物传感器在食品安全检测中的应用

分析了生物传感器的基本原理、结构以及生物传感器的类型和特点,阐述了现代生物传感器技术在微生物检测、食品药物残留与兽药残留、食品添加剂检测和激素检测中的各种应用,讨论了传感技术在食品安全检测中的重要应用及未来发展方向.     

基于Pt-Au-MoS2-ITO传感器对于H2O2的还原检测

实验探究了二硫化钼（MoS₂）作为一种新型材料与贵金属纳米粒子金（Au）、铂（Pt）的复合基底对于过氧化氢（H₂O₂）的还原性检测,采用氧化铟锡导电玻璃（ITO）作为电极,制备出了基于Pt-Au-MoS₂-ITO的生物传感器,为H₂O₂还原性检测的便携性操作打下了基础.实验采用电化学沉积的方法制备材料,同时使用循环伏安（CV）法、计时电流法等传统电化学手段表征了传感器电化学性能,采用场发射扫描电子显微镜（FE-SEM）来表征传感器表面形貌.建立了用于H₂O₂还原检测的、具有高检测限、高灵敏度和宽检测范围的传感器.     

The molecular mechanism of different sensitivity of breast cancer cell lines to TRAIL

Although Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis of various cancer cells, some caner cell lines are resistant to TRAIL-induced cell death. To investigate the molecular mechanisms underlying TRAIL-resistance, two human breast cancer cell lines, MCF-7 (resistant to TRAIL) and MDA-MB-231 (sensitive to TRAIL), were used as a model system to analyze the different sensitivities to TRAIL cytotoxicity. PKCδ inhibitor rottlerin, but not MEK and ERK1/2 inhibitor U0126 nor PI3K inhibitor LY294002, was shown to enhance TRAIL-induced apoptosis in MCF-7 cells significantly, suggesting that PKCδ might play an important role in the resistance of MCF-7 cells to TRAIL. In contrast, rottlerin, U0126, and Ly294002 had no effect on MDA-MB-231 apoptosis induced by TRAIL under the same conditions. Further experiment showed that the combination of rottlerin and TRAIL cleaved PARP in the MCF-7 cells synergistically, but not in the MDA-MB-231 cells. The role of PKCδ in TRAIL-resistant MCF-7 cells was confirmed by knocking down the endogenous PKCδ expression using RNAi technology. Furthermore, caspase-3 reconstitution in MCF-7 cells was unable to alter PKCδ expression, suggesting that innate caspase-3 deficient in the cells does not cause PKCδ high expression. These data provide evidence for the first time that PKCδ plays a critical role in breast cancer cell lines to TRAIL cytotoxicity.     

LAPS同化MTSAT-2水汽资料在一次中尺度大暴雨模拟中的应用

中尺度分析系统LAPS(local analysis and prediction system)在国内已业务化多年,可以融合多种国内观测资料;但是针对卫星资料的融合应用研究还不够充分。为此,实现了LAPS融合MTSAT-2卫星资料的接口;并结合WRF模式,选取2014年7月24~25日发生在江苏及附近地区的一次强降水过程进行模拟。通过对比LAPS系统融合MTSAT-2卫星资料前后的物理量场的差异,以及经WRF模式预报的降水量差异,分析基于LAPS系统同化MTSAT-2资料对暴雨预报的作用。结果表明,LAPS融合MTSAT-2卫星资料后对地面相对湿度场和降水区域分布均有明显改善作用。利用多种评分方法对24 h累计降水进行检验,发现同化MTSAT-2资料对大雨及以上量级降水的预报改善作用明显,特别是对大暴雨级别的降水预报效果改善最为显著。     

锇聚合物修饰丝网印刷电极的辣根过氧化物酶传感器

酶生物传感器检测环境污染应用前景良好。该文采用戊二醛-牛血清白蛋白交联法将锇-聚乙烯基吡啶(Os(bpy)2(PVP)10Cl2,Os-PVP)与辣根过氧化物酶(HRP)依次固定在丝网印刷电极上,制备电流型过氧化氢生物传感器。通过循环伏安法对修饰电极的氧化还原性质进行研究,并采用计时-电流法对传感器的固定化和工作参数进行了研究,以便提高信号响应的灵敏度和稳定性。在最适合条件下,底物在修饰电极表面进行催化反应的表观Michaelis-Menten常数kampp为1.79mmol/L,并确定以HRP酶为标记物的免疫传感器所采用的底物浓度宜大于20倍的kmapp。     

局地分析预报系统LAPS对多种探测资料融合研究及评估

 以武汉暴雨研究所引进的美国局地分析预报系统（LAPS）为基础,利用"973"项目实验收集的华南、长江流域2008年至2010年间的地面、探空的常规、加密观测和多部新一代多普勒雷达数据,通过设计、运行多种LAPS数据融合方案,开展LAPS的本地化试验.分析评估表明,LAPS系统以NCEP再分析数据为背景场的多种观测数据融合,可以改善NCEP再分析场,获得的分析场更接近实况观测.多种观测数据融合的分析场优于单种观测数据融合的分析场.基于多雷达反射率因子拼图,比较LAPS融合多种观测数据得到的分析风场和NCEP再分析风场,结果表明,LAPS分析风场与多雷达反射因子回波拼图的配置更为合理.     

锇聚合物修饰丝网印刷电极的辣根过氧化物酶传感器

酶生物传感器检测环境污染应用前景良好。该文采用戊二醛-牛血清白蛋白交联法将锇-聚乙烯基吡啶(Os(bpy)2(PVP)10Cl2,Os-PVP)与辣根过氧化物酶(HRP)依次固定在丝网印刷电极上,制备电流型过氧化氢生物传感器。通过循环伏安法对修饰电极的氧化还原性质进行研究,并采用计时-电流法对传感器的固定化和工作参数进行了研究,以便提高信号响应的灵敏度和稳定性。在最适合条件下,底物在修饰电极表面进行催化反应的表观Michaelis-Menten常数kampp为1.79 mmol/L,并确定以HRP酶为标记物的免疫传感器所采用的底物浓度宜大于20倍的kmapp。     

Input Split Hydraulic Hybrid Bus and Control Strategy

Simple and efficient energy management strategy is the key to ensure hybrid vehicle performance. Based on hybrid dynamical system theory and the concept of finite state mechanism,power split hybrid connected structure hydraulic hybrid system was proposed and described. In order to meet the demand for driving,the layered advanced control strategy was proposed in this paper,which referred to vehicle driving experience. Using Matlab /Simulink /Stateflow hybrid modeling method, the economy performance and the acceleration performance of the vehicle under the typical city driving cycles were carried on the simulation analysis. The results show that the proposed topology and control strategy can obviously improve engine output characteristic,effectively enhance the vehicle＇s instantaneous power performance and economy,and also has a better adaptability in different traffic environments.     

Engineering Deinococcus radiodurans into biosensor to monitor radioactivity and genotoxicity in environment

Based on a genetically modified radioresistant bacteria Deinococcus radiodurans, we constructed a real time whole cell biosensor to monitor radioactivity and genotoxicity in highly radioactive environ-ment. The enhanced green fluorescence protein (eGFP) was fused to the promoter of the crucial DNA damage-inducible recA gene from D. radiodurans, and the consequent DNA fragment (PrecA-egfp) car-ried by plasmid was introduced into D. radiodurans R1 strain to obtain the biosensor strain DRG300. This engineered strain can express eGFP protein and generate fluorescence in induction of the recA gene promoter. Based on the correlation between fluorescence intensity and protein expression level in live D. radiodurans cells, we discovered that the fluorescence induction of strain DRG300 responds in a remarkable dose-dependent manner when treated with DNA damage sources such as gamma radiation and mitomycin C. It is encouraging to find the widely detective range and high sensitivity of this re-constructed strain comparing with other whole cell biosensors in former reports. These results suggest that the strain DRG300 is a potential whole cell biosensor to construct a detective system to monitor the biological hazards of radioactive and toxic pollutants in environment in real time.     

电流型酶电极生物传感器抗可逆抑制剂干扰的测定方法

电流型酶电极生物传感器在工业领域的应用中经常会遇到酶活性抑制剂干扰问题,在存在酶活性抑制剂的环境下,用酶电极生物传感检测,分析结果会显著偏低。根据电流型酶电极生物传感器的检测原理,设计了一种抗抑制剂干扰的测定方法,传感器正常定标完成后,先按正常方法进行测定,然后用样品加标样进行第二次测定,两次测定具有相同的酶抑制剂环境。通过两次测定结果比较,算出第二次测定所加标样的响应结果,计算出抑制剂对酶活的抑制系数,最终通过第一次测定结果和抑制系数计算出样品中待测物的浓度。这种测定方法能有效消除酶抑制剂对分析结果的影响,拓展酶电极生物传感器在工业领域中的应用范围。