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Peng Chen Xiaojun Luo Guanqi Dai Yuchuan Jiang Yue Luo Shuang Peng Hao Wang Penghui Xie Chen Qu Wenyu Lin Jian Hong Xue Ning Aimin Li 《Experimental & molecular medicine》2020,52(7):1062
Dexmedetomidine (DEX) is an anesthetic that is widely used in the clinic, and it has been reported to exhibit paradoxical effects in the progression of multiple solid tumors. In this study, we sought to explore the mechanism by which DEX regulates hepatocellular carcinoma (HCC) progression underlying liver fibrosis. We determined the effects of DEX on tumor progression in an orthotopic HCC mouse model of fibrotic liver. A coculture system and a subcutaneous xenograft model involving coimplantation of mouse hepatoma cells (H22) and primary activated hepatic stellate cells (aHSCs) were used to study the effects of DEX on HCC progression. We found that in the preclinical mouse model of liver fibrosis, DEX treatment significantly shortened median survival time and promoted tumor growth, intrahepatic metastasis and pulmonary metastasis. The DEX receptor (ADRA2A) was mainly expressed in aHSCs but was barely detected in HCC cells. DEX dramatically reinforced HCC malignant behaviors in the presence of aHSCs in both the coculture system and the coimplantation mouse model, but DEX alone exerted no significant effects on the malignancy of HCC. Mechanistically, DEX induced IL-6 secretion from aHSCs and promoted HCC progression via STAT3 activation. Our findings provide evidence that the clinical application of DEX may cause undesirable side effects in HCC patients with liver fibrosis.Subject terms: Cancer microenvironment, Cell growth 相似文献
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Selective hydrogenation of α,β‐unsaturated carbonyls into saturated carbonyls is important to obtain remunerative products. However, it is still a challenge to achieve high activity and selectivity under mild conditions. Herein, Pd, Ir and bimetallic Pd‐Ir nanoparticles were uniformly deposited with high dispersity on the surface of SiC by a facile impregnation method, respectively. The as‐prepared Pd/SiC catalysts efficiently hydrogenate cinnamaldehyde to hydrocinnamaldehyde at room temperature and atmospheric pressure, and the activity of Pd/SiC is observed further enhanced by adding Ir component (conversion of 100%). In addition, the dependence of Pd‐Ir catalyst activity on Pd/Ir molar ratio confirms a synergistic effect between Ir and Pd, which originates from the electron transfer between Pd and Ir. 相似文献
3.
Jiaguo Huang Yan Lyu Jingchao Li Penghui Cheng Yuyan Jiang Kanyi Pu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(49):17960-17968
Despite its high morbidity and mortality, contrast‐induced acute kidney injury (CIAKI) remains a diagnostic dilemma because it relies on in vitro detection of insensitive late‐stage blood and urinary biomarkers. We report the synthesis of an activatable duplex reporter (ADR) for real‐time in vivo imaging of CIAKI. ADR is equipped with chemiluminescence and near‐infrared fluorescence (NIRF) signaling channels that can be activated by oxidative stress (superoxide anion, O2.?) and lysosomal damage (N‐acetyl‐β‐d ‐glucosaminidase, NAG), respectively. By virtue of its high renal clearance efficiency (80 % injected doses after 24 h injection), ADR detects sequential upregulation of O2.? and NAG in the kidneys of living mice prior to a significant decrease in glomerular filtration rate (GFR) and tissue damage in the course of CIAKI. ADR outperforms the typical clinical assays and detects CIAKI at least 8 h (NIRF) and up to 16 h (chemiluminescence) earlier. 相似文献
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Penghui Li Xiaoxi Hu Shuilin Wu Paul K. Chu Kelvin W.K. Yeung Zushun Xu 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):832-839
Polymerizable rare earth complex Eu(AA)3Phen was synthesized by complexion of europium ion, acrylic acid (AA), and 1,10-phenanthroline (Phen). The structure and fluorescence properties of the complex were studied by elemental analysis, 1H-NMR spectroscopy, and fluorescence spectroscopy. Eu-containing copolymer poly(PEGMA-co-MMA-co-METAC-co-Eu(AA)3Phen) (PPMMEu) was then synthesized by free radical copolymerization of Eu(AA)3Phen and other functional monomers including poly(ethylene glycol) methyl ether methacrylate (PEGMA) and [2-(Methacryloyloxy) ethyl] trimethylammonium chloride (METAC). 1H-NMR spectroscopy and fluorescence spectroscopy were used to characterize the copolymer and the interactions between the copolymer and DNA was investigated by TEM, fluorescence spectroscopy, and agarose gel electrophoresis. The desired luminescent cationic copolymer was successfully obtained. The copolymer can form micelles in water solution and can efficiently bind to DNA molecules through electrostatic interaction. The results suggest the potential use of PPMMEu in bioprobes and gene vectors. 相似文献
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A label-free DNA-based electrochemical biosensor owning high sensitivity and selectivity has been established for detecting bisphenol A in a wide range of applications. Coupling the high electrochemical performance of graphene oxide-thionine-Au nanomaterial with the specific binding capacity of the aptamers to BPA, the monitoring of trace amount of BPA was realized, the detection limit was 3.3 pg ⋅ mL−1 with strong anti-interference. Besides, using molecular docking, it was found that BPA binds to the bases DC-49, DC-51, DG-52, DG-53 and DA-63 on the aptamer via hydrogen bonding and π-π stacking interactions. Finally, the biosensor had been successfully applied in different real samples. 相似文献
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通过极差分析研究了不同浓度的硝酸镧和生长素组合对长柄扁桃试管苗生根的影响。结果表明:对长柄扁桃生根影响的主次因素为硝酸镧(La(NO3)3)>吲哚丁酸(IBA)>吲哚乙酸(IAA),最优组合为La(NO3)320 mg·L-1+IBA 0.2 mg·L-1+IAA 0.2 mg·L-1。在此条件下培养42 d后,长柄扁桃试管苗根的诱导频率达到89%,平均根长达到9.2 cm,每株根的平均个数为9.7个。对长柄扁桃的根组织活力进行测定,结果表明添加镧的处理组根系还原力是对照(不加镧)组的1.57倍。经过移栽驯化2个月后,长柄扁桃组培苗的移栽成活率达到94%,株高是对照的1.53倍。 相似文献
7.
Dr. Qing Li Shenhua Li Dr. Shasha He Wan Chen Penghui Cheng Dr. Yan Zhang Prof. Qingqing Miao Prof. Kanyi Pu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(18):7084-7089
Discriminative detection of invasive and noninvasive breast cancers is crucial for their effective treatment and prognosis. However, activatable probes able to do so in vivo are rare. Herein, we report an activatable polymeric reporter (P-Dex) that specifically turns on near-infrared (NIR) fluorescent and photoacoustic (PA) signals in response to the urokinase-type plasminogen activator (uPA) overexpressed in invasive breast cancer. P-Dex has a renal-clearable dextran backbone that is linked with a NIR dye caged with an uPA-cleavable peptide substrate. Such a molecular design allows P-Dex to passively target tumors, activate NIR fluorescence and PA signals to effectively distinguish invasive MDA-MB-231 breast cancer from noninvasive MCF-7 breast cancer, and ultimately undergo renal clearance to minimize the toxicity potential. Thus, this polymeric reporter holds great promise for the early detection of malignant breast cancer. 相似文献
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Yi Yang Xueyi He Penghui Zhang Yassin H. Andaloussi Hailu Zhang Zhongyi Jiang Yao Chen Shengqian Ma Peng Cheng Zhenjie Zhang 《Angewandte Chemie (International ed. in English)》2020,59(9):3678-3684
Developing new materials for the fabrication of proton exchange membranes (PEMs) for fuel cells is of great significance. Herein, a series of highly crystalline, porous, and stable new covalent organic frameworks (COFs) have been developed by a stepwise synthesis strategy. The synthesized COFs exhibit high hydrophilicity and excellent stability in strong acid or base (e.g., 12 m NaOH or HCl) and boiling water. These features make them ideal platforms for proton conduction applications. Upon loading with H3PO4, the COFs (H3PO4@COFs) realize an ultrahigh proton conductivity of 1.13×10?1 S cm?1, the highest among all COF materials, and maintain high proton conductivity across a wide relative humidity (40–100 %) and temperature range (20–80 °C). Furthermore, membrane electrode assemblies were fabricated using H3PO4@COFs as the solid electrolyte membrane for proton exchange resulting in a maximum power density of 81 mW cm?2 and a maximum current density of 456 mA cm?2, which exceeds all previously reported COF materials. 相似文献
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为了获得边坡逐孔爆破最佳降振微差时间,以某个实际边坡逐孔微差爆破施工现场为原型,先利用ANSYS建立二维静态模型,借助有限元折减法确定自然状态下的潜在滑动面和静态安全系数;基于已确定的二维潜在滑动面重新建立同尺寸同性质的三维逐孔微差爆破动态模型,利用LS-DYAN进行动力分析,整个过程分别设置同排3个炮孔0、17、25、42和65 ms等5种不同孔间微差起爆方式;同时,对该施工现场进行排、孔间(25 ms,17 ms)、(25 ms,25 ms)、(25 ms,42 ms)、(25 ms,65 ms)等4种微差时间控制的等比例相似小炮测振实验。提取模拟结果中3个炮孔同时起爆时滑面单元的应力数值代入极限平衡法计算公式,绘制了冲击载荷作用下边坡稳定性系数曲线,通过对曲线的理论分析发现,最佳降振微差时间约为48 ms;而三维数值模拟和测振实验结果均显示,孔间微差时间取42 ms时降振效果较佳。这说明,边坡稳定性系数曲线给出的微差时间与模拟和实验结果较为接近,可为今后边坡逐孔微差爆破降振研究提供参考。 相似文献
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