Piperine Targets Different Drug Resistance Mechanisms in Human Ovarian Cancer Cell Lines Leading to Increased Sensitivity to Cytotoxic Drugs

Our goal was to examine the anticancer effects of piperine against the resistant human ovarian cancer cells and to explore the molecular mechanisms responsible for its anticancer effects. Our study used drug-sensitive ovarian cancer cell line W1 and its sublines resistant to paclitaxel (PAC) and topotecan (TOP). We analyzed the cytotoxic effect of piperine and cytostatic drugs using an MTT assay. The impact of piperine on protein expression was determined by immunofluorescence and Western blot. We also examined its effect on cell proliferation and migration. We noticed a different level of piperine resistance between cell lines. Piperine increases the cytotoxic effect of PAC and TOP in drug-resistant cells. We observed an increase in PTPRK expression correlated with decreased pTYR level after piperine treatment and downregulation of P-gp and BCRP expression. We also noted a decrease in COL3A1 and TGFBI expression in investigated cell lines and increased COL3A1 expression in media from W1PR2 cells. The expression of Ki67 protein and cell proliferation rate decreased after piperine treatment. Piperine markedly inhibited W1TR cell migration. Piperine can be considered a potential anticancer agent that can increase chemotherapy effectiveness in cancer patients.     

2种侧围加强内框总成检具结构对比分析

概述了侧围加强内框总成与周边零件的匹配关系,从检具操作的人机工程出发,描述了侧围加强内框总成检具的2种定位方式和结构设计,对比了2种定位方式对于检测结果的影响,总结了其优点和弊端,结果表明侧围加强内框总成检具采用车内方向朝下的定位方式效果更好。     

Fabrication and properties of the superhydrophobic ceria-based composite coating on magnesium alloy

A superhydrophobic ceria-based composite coating is developed to improve anticorrosion properties of AZ61 magnesium alloy, fabricating via chemical conversion method followed by hydrothermal treatment. The cerium conversion coating has a block structure with microcracks. After the hydrothermal treatment, a dense CeO₂ layer, porous CeO₂ nanorods, and stearic absorbing layers are grown stepwise on the conversion coating. And the composite coating is hydrophobic or even superhydrophobic and has almost no microcracks. As the hydrothermal reaction time increases, the water contact angle of the composite coating first increases and then decreases, and it reaches the maximum value of 152° after hydrothermal treatment for 4 h. Both the dense CeO₂ layer and the superhydrophobic stearic absorbing layer can effectively prevent the electrolyte from contacting the substrate; the corrosion current density of the superhydrophobic composite coating is lower than that of the hydrophilic composite coating and the cerium conversion coating, and has the best corrosion resistance.     

Resveratrol as Chemosensitizer Agent: State of Art and Future Perspectives

Resistance to chemotherapy still remains a major challenge in the clinic, impairing the quality of life and survival rate of patients. The identification of unconventional chemosensitizing agents is therefore an interesting aspect of cancer research. Resveratrol has emerged in the last decades as a fascinating molecule, able to modulate several cancer-related molecular mechanisms, suggesting a possible application as an adjuvant in cancer management. This review goes deep into the existing literature concerning the possible chemosensitizing effect of resveratrol associated with the most conventional chemotherapeutic drugs. Despite the promising effects observed in different cancer types in in vitro studies, the clinical translation still presents strong limitations due to the low bioavailability of resveratrol. Recently, efforts have been moved in the field of drug delivery to identifying possible strategies/formulations useful for a more effective administration. Despite the necessity of a huge implementation in this research area, resveratrol appears as a promising molecule able to sensitize resistant tumors to drugs, suggesting its potential use in therapy-refractory cancer patients.     

Structure,mechanical and thermal properties of Y-doped CrAlN coatings

CrAlYN coatings with different Y contents (0, 5 and 12 at.%) were deposited by cathodic arc evaporation to investigate the influence of Y-addition on the structure, mechanical and thermal properties of CrAlN coatings by using X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, thermal gravimetric analysis and nanoindentation. The structural transformation of single phase cubic Cr_0.42Al_0.58N and Cr_0.39Al_0.56Y_0.05N coatings to cubic–wurtzite mixed Cr_0.32Al_0.56Y_0.12N coating leads to a drop in hardness from (30.2±0.7) GPa of Cr_0.42Al_0.58N and (32.0±1.0) GPa of Cr_0.39Al_0.56Y_0.05N to (25.2±0.7) GPa of Cr_0.32Al_0.56Y_0.12N. The incorporation of 5 at.% Y retards the thermal decomposition of CrAlN, verified by the postponed precipitation of w-AlN and N-loss upon annealing. Correspondingly, Cr_0.39Al_0.56Y_0.05N coating consistently exhibits the highest hardness value during thermal annealing. Nevertheless, alloying with Y exerts an adverse effect on the oxidation resistance of CrAlN.     

Integrative improvement on thermophysical properties and ablation resistance of laminated carbon/carbon composites modified by in situ grown HfC nanowires onto carbon fiber cloths

HfC nanowires modified carbon fiber cloth laminated carbon/carbon (HfC_nw-C/C) composites were fabricated by in situ growth of HfC nanowires on carbon cloths via catalytic CVD, followed with lamination of the cloths and densification by pyrolytic carbon (PyC). Morphologies, thermal conductivity, coefficient of thermal expansion (CTE), and ablation resistance of the composites were investigated. Due to the loading of HfC nanowires, the matrix PyC with low texture was obtained; the thermal conductivity of the composites in the Z direction was enhanced from 100℃ to 2500℃; CTE along the X–Y direction also decreased in the range of 2060 ℃ – 2500 ℃, which reaches the maximum of 24 % at 2500℃. Moreover, the 20s-ablation-resistance of HfC_nw-C/C composites exhibits mass and linear ablation rates of 5.3 mg/s and 21.0 μm/s, which are 40 % and 37 % lower than those of pure C/C composites, respectively. Our work shows laminated HfC_nw-C/C composites are a promising candidate for high-temperature applications.     

抗FGF-2纳米抗体抑制碱烧伤诱导大鼠角膜血管新生

目的：研究抗成纤维细胞生长因子（FGF-2）纳米抗体对碱烧伤诱导的大鼠角膜血管生成的治疗作用。方法：将SD大鼠分为：假手术组（Sham），模型组（Model，直径为3 mm的浸有1 mol/L NaOH溶液圆形滤纸贴于大鼠眼角膜中央处30 s，制备大鼠碱烧伤血管生成模型）和治疗组（Treatment，术后7天至21天用3 mg/mL的抗FGF-2纳米抗体溶液滴眼，每日3次，每次10 μL，共14天）。通过体视显微镜和CD31免疫组织化学染色计算大鼠角膜血管生成情况。实时荧光定量PCR、酶联免疫吸附测定和免疫组织化学染色3种方法检测抗血管内皮生长因子（VEGF）和FGF-2的mRNA和蛋白表达水平。结果：（1）血管：治疗组较模型组的面积显著减少，血管管腔较窄（P<0.05），在药物干预14天后，差异最为显著；（2）FGF-2的mRNA和蛋白表达水平：模型组与治疗组的结果相近（P>0.05）；（3）VEGF的mRNA和蛋白表达水平：治疗组显著高于模型组（P<0.05）。此外，假手术组的持续给药也使得VEGF表达显著增加（P<0.05）。 结论：抗FGF-2纳米抗体可抑制由碱烧伤诱导的角膜血管新生，但也使得正常大鼠角膜或病理大鼠角膜的VEGF表达水平代偿性升高。     

Direct View on the Origin of High Li+ Transfer Impedance in All-Solid-State Battery

Large interfacial resistance plays a dominant role in the performance of all-solid-state lithium-ion batteries. However, the mechanism of interfacial resistance has been under debate. Here, the Li⁺ transport at the interfacial region is investigated to reveal the origin of the high Li⁺ transfer impedance in a LiCoO₂(LCO)/LiPON/Pt all-solid-state battery. Both an unexpected nanocrystalline layer and a structurally disordered transition layer are discovered to be inherent to the LCO/LiPON interface. Under electrochemical conditions, the nanocrystalline layer with insufficient electrochemical stability leads to the introduction of voids during electrochemical cycles, which is the origin of the high Li⁺ transfer impedance at solid electrolyte-electrode interfaces. In addition, at relatively low temperatures, the oxygen vacancies migration in the transition layer results in the formation of Co₃O₄ nanocrystalline layer with nanovoids, which contributes to the high Li⁺ transfer impedance. This work sheds light on the mechanism for the high interfacial resistance and promotes overcoming the interfacial issues in all-solid-state batteries.     

巨型水轮发电机剪断销研发与质量控制

为获得设计需要的巨型水轮发电机剪断销的剪切力,得到剪切力波动受控的批量剪断销,通过拉伸试验、冲击试验、硬度试验和剪断销剪切试验等讨论了全尺寸剪断销剪切试验的可行性,分析了剪切试验时正常剪断和非正常剪断的剪断销材料性能差异,探究了剪断销的剪切力质量稳定性控制方法。结果表明:控制剪断销料坯的布氏硬度波动,可实现间接控制剪断销剪切强度的波动;通过试验总结的六步法可达到控制批量剪断销质量和剪切力波动的目的。     

Tuning of shear thickening behavior and elastic strength of polyvinylidene fluoride via doping of ZnO-graphene

ZnO rice like nonarchitects are grafted on the graphene carbon core via a rapid microwave synthesis route. The prepared grafted systems are characterized via XRD, SEM, RAMAN, and XPS to examined the structural and morphological parameters. Zinc oxide grafted graphene sheets (ZnO-G) are further doped in β-phase of polyvinylidene fluoride (PVDF) to prepare the polymer nanocomposites (PNCs) via mixed solvent approach (THF/DMF). β-phase confirmation of PVDF PNCs is done by FTIR studies. It is observed that ZnO-G filler enhances the β-phase content in the PNCs. Non-doped PVDF and PNCs are further studied for rheological behavior under the shear rate of 1–100 s⁻¹. Doping of ZnO-G dopant to the PVDF matrix changes its discontinuous shear thickening (DST) behavior to continues shear thickening behavior (CST). Hydrocluster formation and their interaction with the dopant could be the reason for this striking DST to CST behavioral change. Strain amplitude sweep (10⁻³% -10%) oscillatory test reveals that the PNCs shows extended linear viscoelastic region with high elastic modulus and lower viscous modulus. Effective shear thickening behavior and strong elastic strength of these PNCs present their candidature for various fields including mechanical and soft body armor applications.