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1.
Zhang  Chengxiang  Zhang  Xinfu  Zhao  Weiyu  Zeng  Chunxi  Li  Wenqing  Li  Bin  Luo  Xiao  Li  Junan  Jiang  Justin  Deng  Binbin  McComb  David W.  Dong  Yizhou 《Nano Research》2019,12(4):855-861

Triple-negative breast cancer (TNBC) is one type of the most aggressive breast cancers with poor prognosis. It is of great urgency to develop new therapeutics for treating TNBC. Based on current treatment guideline and genetic information of TNBC, a combinational therapy platform integrating chemotherapy drugs and mRNA encoding tumor suppressor proteins may become an efficacious strategy. In this study, we developed paclitaxel amino lipid (PAL) derived nanoparticles (NPs) to incorporate both chemotherapy drugs and P53 mRNA. The PAL P53 mRNA NPs showed superior properties compared to Abraxane® and Lipusu® used in the clinic including high paclitaxel loading capacity (24 wt.%, calculated by paclitaxel in PAL), PAL encapsulation efficiency (94.7% ± 6.8%) and mRNA encapsulation efficiency (88.7% ± 0.7%). Meanwhile, these NPs displayed synergetic cytotoxicity of paclitaxel and P53 mRNA in cultured TNBC cells. More importantly, we demonstrated in vivo anti-tumor efficacy of PAL P53 mRNA NPs in an orthotopic TNBC mouse model. Overall, these chemotherapy drugs derived mRNA NPs provide a new platform to integrate chemotherapy and personalized medicine using tumor genetic information, and therefore represent a promising approach for TNBC treatment.

  相似文献   
2.
Stream gauging data play a vital role in the planning of flood mitigation strategies. A study of the value of stream flow data for the design of levee systems shows that the availability of a reasonable sample of pertinent data can be worth many times the cost of collecting that data.  相似文献   
3.
This paper describes a tool to aid the development of computer vision applications for pixel-level diagnosis. A conceptual framework for constructing pixel processors is described. The proposed tool is based on two domains: one deals with numerical images, named features, and the other deals with symbolic images, named classes. A reduced set of image and operator types is defined. Based on it, an object-oriented language is described. The main objects define features and classes and their associated operators, namely procedures, classifiers, and rules. All system control is goal oriented and is designed to provide symbolic images as results when a request is received from a higher level of the image understanding system. Some knowledge engineering concepts, such as certainty control and instances, are also included.  相似文献   
4.
We describe the characterization, ferroelectric phase stability and polarization switching in strain‐free assemblies of PbZr0.3Ti0.7O3 (PZT) nanostructures. The 3‐dimensionally ordered macroporous structures present uniquely large areas and volumes of PZT where the microstructure is spatially modulated and the composition is homogeneous. Variable temperature powder X‐ray diffraction (XRD) studies show that the global structure is crystalline and tetragonal at room temperature and undergoes a reversible tetragonal to cubic phase transition on heating/cooling. The measured phase‐transition temperature is 50–60 °C lower than bulk PZT of the same composition. The local ferroelectric properties were assessed using piezoresponse force spectroscopy that reveal an enhanced piezoresponse from the nanostructured films and demonstrate that the switching polarization can be spatially mapped across these structures. An enhanced piezoresponse is observed in the nanostructured films which we attribute to the formation of strain free films, thus for the first time we are able to assess the effects of crystallite‐size independently of internal stress. Corresponding polarization distributions have been calculated for the bulk and nanostructured materials using a direct variational method and Landau‐Ginzburg‐Devonshire (LGD) theory. By correlating local and global characterization techniques we have for the first time unambiguously demonstrated the formation of tetragonal and ferroelectric PZT in large volume nanostructured architectures. With the wide range of materials available that can be formed into such controlled architectures we conclude that this study opens a pathway for the effective studies of nanoscale ferroelectrics in uniquely large volumes.  相似文献   
5.
介绍了电磁渡测量流速的基本原理一多普勒效应.分析了影响低流速测量的主要干扰因素一发射泄漏干扰和旁瓣干扰。根据接收信号中发射泄漏干扰不变的特性,提出了去均值滤波的方法来消除干扰,对数据进行预处理;根据旁瓣干扰的信号特性,提出了通过频谱加窗和二次加权平均法构造频域带通滤波器来抑制干扰的方法,在仿真比较完各个窗函数的性能之后...  相似文献   
6.
单层钢板组合剪力墙是一种很好的抗侧力构件,在高层建筑中得到广泛应用。文章利用ANSYS对单层钢板组合剪力墙进行弹塑性分析,考察了不同参数的变化对其抗侧性能的影响,并得出相应结论。  相似文献   
7.
针对部分提质褐煤型煤防水性差的缺点,制备乳化硅油作为型煤的防水剂,在硅油乳液的制备过程中,最佳亲水亲油平衡值(HLB)为10.5,硅油与乳化剂的最佳质量比为4∶1,最佳乳化方式为转相乳化法。试验结果表明:乳化硅油作为防水剂可大幅度增强提质褐煤型煤的防水性,3种不同质量分数的硅油乳液(5%、10%、30%)分别可使原本不具有防水性的型煤60 m in的平均吸水率降至6.98%、5.51%和1.98%。  相似文献   
8.
目的探讨合成抗菌肽TachyplesinⅠ在体外的生物活性及在模拟消化环境中的降解规律。方法采用不同温度、pH值、阳离子浓度、溶剂极性、模拟消化环境分别处理TachyplesinⅠ,通过检测TachyplesinⅠ生物活性的变化分析其稳定性;检测TachyplesinⅠ对小鼠血细胞的溶血活性;通过HPLC图谱变化评定TachyplesinⅠ在模拟消化环境中的降解情况。结果 TachyplesinⅠ在低于100℃、pH值小于10.3的情况下具有稳定性,阳离子浓度和溶液极性对TachyplesinⅠ的抗菌活性具有一定影响;在TachyplesinⅠ浓度大于80 mg/L时,作用时间大于30 min时,表现出一定的溶血活性;TachyplesinⅠ在模拟胃液、胃黏膜匀浆和血浆系统中表现出很高的稳定性,色谱峰型基本未改变,几乎无降解作用,TachyplesinⅠ的最小抑菌浓度为5.0~20.0 mg/L;在模拟小肠液和小肠黏膜匀浆系统中稍微敏感,色谱峰型降低,出现小杂峰,生物活性明显降低,最小抑菌浓度在80~160 mg/L之间。结论 TachyplesinⅠ具有较强的高温耐受性,在酸性条件下稳定,同时具有一定的耐受体内蛋白酶降解的能力。  相似文献   
9.

Background  

Rye products have been demonstrated to lower the acute insulin demand, induce a low and prolonged blood glucose response (high Glycemic Profile, GP) and reduce subclinical inflammation. These products may therefore contribute to a lowered risk of obesity, type 2 diabetes and cardio vascular disease. The objective of the present paper was to evaluate the mechanism for a reduced postprandial insulin demand with rye products, and to explore possible appetite regulating properties.  相似文献   
10.
This work studied X-ray powder diffraction (XRD), electrical resistivity and electron paramagnetic resonance (EPR) measurements for Bi1.8Pb0.4Sr2Ca2.1Cu3−xRuxO10+δ (0.0 ≤ x ≤ 0.4) superconducting samples. XRD analysis and electrical resistivity data showed that the low-content of Ru, x ≤ 0.05, enhanced both the phase formation and the superconducting transition temperature of (Bi, Pb)-2223 phase. A phase change from (Bi, Pb)-2223 phase to (Bi, Pb)-2212 phase was reported for x ≥ 0.15. Two EPR lines were observed for 0.0 ≤ x ≤ 0.075, indicating the presence of both (Bi, Pb)-2223 and (Bi, Pb)-2212 phases. While, one EPR line was observed for x ≥ 0.15, corresponding to the (Bi, Pb)-2212 phase formation. The number of spins (N) participating in the resonance and its spin paramagnetic susceptibility (χ), for the two phases, were calculated as a function of both Ru-content and temperature. In addition, we reported the variation of activation energy (Ea), Curie constant (C), Curie temperature (θ) and effective magnetic moment (μ) with Ru-content.  相似文献   
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