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101.
4-Anilinoquinazoline derivatives function as tyrosine kinase inhibitors (TKIs). Novel TKIs are needed for cancer mutations and drug-resistant cells. We designed and synthesized 4-anilinoquinazoline derivatives with substitutions at quinazoline positions 6, 7 and 4 using a binding model with multi-target receptor tyrosine kinases, and assessed their antitumor activity against five human tumor cell lines (HepG2, A549, MCF-7, DU145, SH-SY5Y). The majority of the compounds inhibited the proliferation of all the cancer cell types, with some compounds displaying selective inhibition. Compounds 21, 25, 27, and 37 displayed IC50 values of 7.588, 8.619, 6.936, and 8.516 μM, respectively, for A549 cells, which were much lower than that of Gefitinib (14.803 μM). Compound 32 displayed an IC50 value of 2.756 μM for DU145 cells. The representative compound 40 had unexceptionable broad-spectrum inhibition for all cancer cell types, and demonstrate inhibition of vascular endothelial growth factor receptor 2 (VEGFR-2), platelet-derived growth factor receptor beta (PDGFR-β), and epidermal growth factor receptor (EGFR) with IC50 values of 46.4, 673.6 and 384.8 nM, respectively, which were similar to those of Sorafenib for VEGFR-2 and PDGFR-β (140.6 and 582.7 nM, respectively). Molecular docking results supported the molecular level assay results. Data for production of reactive oxygen species and assessment of matrix metalloproteinase corroborated the strong anti-proliferative effect of compound 40. The compound also displayed robust antitumor efficacy and relativity lower toxicity in a xenograft model. These attributes were similar to those of Sorafenib. Compound 40 drug warrants further study as a candidate.  相似文献   
102.
磁场在生活中无处不在,为探究磁场的生物学效应,大量研究工作已经开展。斑马鱼作为新兴的模式生物,在探明磁场与生理功能关系方面具有重要作用。本文梳理了当前磁生物学在斑马鱼上的相关研究。已有研究表明磁场会导致斑马鱼生长畸形、发育延迟和细胞凋亡,影响斑马鱼的游泳行为和方向偏好,也会改变其昼夜节律,还会对生殖和免疫功能产生影响;斑马鱼可能具有不止一种的磁感应机制,除了目前已提出的磁矿石晶体模型、自由基对模型和电磁感应模型等磁感应模型外,磁场引起的DNA损伤、Ca2+稳态异常、微管聚合速率改变、应激反应、生物钟基因cry的表达改变等可部分解释上述现象。针对存在的生物磁感应研究中存在的参数不一和机制不清晰等问题,结合斑马鱼优势,本文提出未来斑马鱼在磁生物学研究中的潜在方向:基于斑马鱼建立磁场和生物参数可控的磁生物学研究模型;非侵入性活体追踪相关生命活动过程,可视化研究磁生物学现象;基于Cry蛋白开展磁场与生物节律关系的研究。  相似文献   
103.
Over the past two decades, strategies for sustainable development and water environment governance have become the main ways to improve regional water-use efficiency. However, the evolutionary characteristics and drivers of the regional water-use efficiency remain unclear, and the effectiveness of national strategic instruments must still be evaluated. The study uses the minimum distance to the strong efficient frontier model (MinDS) to measure water-use efficiency in the Yangtze River Economic Belt, examines the evolutionary characteristics of water-use efficiency from spatial and temporal perspectives, and further investigates drivers of the evolution of the water-use efficiency. The results indicate that the water-use efficiency in the Yangtze River Economic Belt has greatly improved and been maintained at a high level, especially after the national strategy for this economic belt was established. Water-use efficiency improvement is closely related to water environment treatment. There exists a significant spillover effect on the water-use efficiency in the provinces of the Yangtze River Economic Belt. High-level provinces are helpful in driving neighboring provinces to improve their water-use efficiency, while low-level provinces play a negative role. This study confirms the effectiveness of the national strategy and provides a useful perspective for interprovincial water-use efficiency improvement.  相似文献   
104.
目的:探讨低浓度乙醇对糖尿病大鼠心肌损伤后线粒体融合素2(mfn2)表达的影响。方法:糖尿病大鼠模型采用链脲佐菌素55 mg/kg腹腔注射,分为正常对照组(Control组),糖尿病组(DM组)和糖尿病+乙醇组(DM+EtOH组)(n=6);糖尿病+乙醇组于造模成功1周后给予2.5%乙醇日常饮用,1周后改为5%的乙醇持续至8周,8周后行离体心脏灌流,测定心室血流动力学指标,应用自动生化分析仪测定血清乳酸脱氢酶(LDH)和天门冬氨酸转移酶(AST)的水平。Western blot测定左心室组织线粒体融合素2(mfn2)蛋白表达,免疫组化测定心肌组织mfn2蛋白表达。结果:与control组大鼠心肌相比,DM组大鼠心率、左室发展压、左室做功下降,左室舒张末压抬高,血清LDH及AST升高明显,心室mfn2蛋白表达降低;与DM组大鼠心肌相比,DM+EtOH组明显促进心率、左室发展压、左室做功的恢复,降低左室舒张末压,同时降低LDH的水平和AST的释放,mfn2的蛋白表达增高。结论:糖尿病大鼠心肌损伤时,心肌mfn2表达降低;低浓度乙醇增强mfn2在心肌组织中的表达,提示mfn2的增加可能参与低浓度乙醇对糖尿病诱发的心肌损伤的保护作用。  相似文献   
105.
In order to create novel, potent and selective anti-cancer agents, the action of 4-(4-fluorophenyl)amino-5,6,7-trimethoxyquinazoline (compound 1018) on 10 different kinds of tumour cells were assayed by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide]. It possesses a broad spectrum of anti-cancer activity. The mechanism of action of 4-(4-fluorophenyl)amino-5,6,7-trimethoxyquinazoline (hereafter referred to as compound 1018) against tumour cells was studied in androgen-independent prostate cancer PC-3 cells by microscopic observation, LDH (lactate dehydrogenase) release assay and Western blotting. Its activity was dose-dependent, with an IC50 of 13.0±1.4 μM after 72 h treatment. Microscopy and LDH release assay indicated that the effect was through anti-proliferation rather than cytotoxicity. Western blot analysis also showed that treatment of cells with 50 μM compound 1018 for 30 min almost completely inhibited EGF (epidermal growth factor)-induced phosphorylation of ERK1/2 (extracellular-signal-regulated kinase 1/2), which suggests that its anti-proliferative effect is largely associated due to ERK1/2 activation being inhibited. Thus compound 1018 is a potential anti-cancer agent.  相似文献   
106.
目的:探讨乙醇后处理心肌保护作用是否与一氧化氮生成有关。方法:局部结扎冠状动脉左前降支30min,复灌120 min复制离体大鼠心肌缺血/复灌模型。心肌缺血末5 min,复灌初期10min给予乙醇50mmol/L,共灌流15 min进行乙醇后处理干预。实验随机分为五组,正常组,缺血/复灌组,乙醇后处理组,乙醇后处理+L-NAME组和乙醇后处理+苍术苷组。测定心室动力学指标和复灌期间冠脉流出液中乳酸脱氢酶(LDH)含量,TTC染色法测定心肌梗死面积,硝酸还原法测定心肌组织一氧化氮(NO)含量。RT-PCR检测左心室前壁心尖组织Bc-l2和BaxmRNA的表达。结果:与单纯缺血/复灌相比,乙醇后处理明显促进了左室发展压、左室做功的恢复,降低复灌期冠脉流出液中LDH的释放和心肌梗死面积,心肌组织NO释放减少,Bc-l 2/Bax mRNA比值增高。一氧化氮合酶抑制剂L-NAME和线粒体渗透性转换孔道开放剂苍术苷均抑制了乙醇后处理心室功能的恢复、LDH释放的减少和梗死面积的降低,心肌组织NO释放进一步减少,Bc-l 2/Bax mRNA比值降低。结论:乙醇后处理的心肌保护作用可能与减少NO的释放、抑制线粒体渗透性转换孔道的开放和抑制细胞凋亡的发生有关。  相似文献   
107.
目的:比较骨髓间充质干细胞、脂肪间充质干细胞、滑膜间充质干细胞3种间充质干细胞的成软骨分化潜能,为软骨组织工程中种子细胞的选择提供实验依据。方法:采用贴壁法分别分离提取兔骨髓间充质干细胞、脂肪间充质干细胞、滑膜间充质干细胞3种间充质干细胞,并进行传代培养,绘制3种间充质干细胞的生长曲线并比较其倍增时间。将3种间充质干细胞成软骨诱导14 d后,行甲苯胺蓝染色及II型胶原免疫组化染色以观测3种细胞成软骨分化能力。结果:脂肪间充质干细胞的倍增时间短于骨髓间充质干细胞,滑膜间充质干细胞的倍增时间最短;3种细胞成软骨诱导14 d后均产生糖胺聚糖和II型胶原,且组与组之间II型胶原表达水平的差异有统计学意义,骨髓间充质干细胞组高于脂肪间充质干细胞组(P0.01),滑膜间充质干细胞组高于骨髓间充质干细胞组(P0.01)。结论:在一定的培养条件下,3种间充质干细胞均有一定的成软骨细胞分化潜能,滑膜间充质干细胞最快的增殖速度及最强的成软骨分化潜能。  相似文献   
108.
109.
目的:观察乙醇激动乙醛脱氢酶2(ALDH2)对糖尿病大鼠肾脏c-Jun氨基末端激酶(JNK)表达的影响。方法:18只健康雄性SD大鼠随机分为正常对照组、糖尿病组、乙醇+糖尿病组(n=6)。造模8周后,测定血糖、糖化血红蛋白、肾功能、24h尿蛋白含量等指标,测定肾重指数,观察肾脏病理结构改变,检测肾脏组织ALDH2、p-JNK及JNK蛋白表达。结果:与正常对照组相比,糖尿病组血糖、糖化血红蛋白、尿素氮、肌酐、24h尿蛋白量及肾重指数均明显升高。病理切片显示:肾小球系膜基质增多、基底膜增厚、毛细血管腔变窄。肾脏组织ALDH2蛋白表达下降,p-JNK、JNK蛋白表达增加,p-JNK/JNK显著增高。给予乙醇干预后,肾功能损伤降低,病理改变减轻,肾脏组织ALDH2增高,p-JNK、JNK表达下降,p-JNK/JNK降低。结论:增加ALDH2表达可能通过抑制JNK信号通路的活性减轻糖尿病大鼠肾脏损伤。  相似文献   
110.
目的探讨嫌色性肾细胞癌(chromophobe renal cell carcinoma,CRCC)和嗜酸细胞瘤(oncocytoma)的临床病理学特征,提高对二者的认识和诊疗水平。方法对手术切除的5例CRCC和2例Oncocytoma进行肉眼和光镜观察、免疫组织化学染色,分析其临床病理学差异。结果 CRCC以实体结构为主、胞质半透明或嗜酸性颗粒状、核皱缩且核周有空晕;Oncocytoma以巢状结构为主,胞质嗜酸颗粒状、核圆形、核仁小。免疫组化染色显示两者均呈E-cadherin、EMA、CK20、vimentin阳性;CRCC瘤细胞CD10和CK7强阳性而S-100蛋白阴性,5名患者随访8~32个月,其中1例手术12个月后由于转移死亡;Oncocytoma瘤细胞S-100蛋白强阳性、CD10和CK7阴性,2名患者随访41个月,均未出现复发和转移。结论 CRCC和oncocytoma二者形态学各有特征,免疫表型相似,二者鉴别诊断主要在于生长方式和细胞学特征。综上所述:CRCC为惰性肿瘤,Oncocytoma为良性肿瘤,预后较好,手术切除后极少发生复发和转移。  相似文献   
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