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Overexpression of PbrGA2ox1 enhances pear drought tolerance through the regulation of GA_(3)-inhibited reactive oxygen species detoxification and abscisic acid signaling
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作者 Guoling Guo Haiyan Zhang +10 位作者 Weiyu Dong Bo Xu Youyu Wang Qingchen Zhao Lun Liu Xiaomei Tang Li Liu Zhenfeng Ye Wei Heng Liwu Zhu Bing Jia 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期2989-3011,共23页
Drought stress is a devastating natural disaster driven by the continuing intensification of global warming,which seriously threatens the productivity and quality of several horticultural crops,including pear.Gibberel... Drought stress is a devastating natural disaster driven by the continuing intensification of global warming,which seriously threatens the productivity and quality of several horticultural crops,including pear.Gibberellins(GAs)play crucial roles in plant growth,development,and responses to drought stress.Previous studies have shown significant reductions of GA levels in plants under drought stress;however,our understanding of the intrinsic regulation mechanisms of GA-mediated drought stress in pear remains very limited.Here,we show that drought stress can impair the accumulation of bioactive GAs(BGAs),and subsequently identified PbrGA2ox1 as a chloroplast-localized GA deactivation gene.This gene was significantly induced by drought stress and abscisic acid(ABA)treatment,but was suppressed by GA_(3)treatment.PbrGA2ox1-overexpressing transgenic tobacco plants(Nicotiana benthamiana)exhibited enhanced tolerance to dehydration and drought stresses,whereas knock-down of PbrGA2ox1 in pear(Pyrus betulaefolia)by virus-induced gene silencing led to elevated drought sensitivity.Transgenic plants were hypersensitive to ABA,and had a lower BGAs content,enhanced reactive oxygen species(ROS)scavenging ability,and augmented ABA accumulation and signaling under drought stress compared to wild-type plants.However,the opposite effects were observed with PbrGA2ox1 silencing in pear.Moreover,exogenous GA_(3)treatment aggravated the ROS toxic effect and restrained ABA synthesis and signaling,resulting in the compromised drought tolerance of pear.In summary,our results shed light on the mechanism by which BGAs are eliminated in pear leaves under drought stress,providing further insights into the mechanism regulating the effects of GA on the drought tolerance of plants. 展开更多
关键词 PEAR GIBBERELLIN drought stress PbrGA2ox1 reactive oxygen species abscisic acid
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Extraction Equilibria of Trimellitic and [ 1,1′-Biphenyl]-2,2′-dicarboxylic Acid with 1-Octanol, 50%TBP, and 10%TRPO in Kerosene 被引量:2
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作者 周智勇 秦炜 戴猷元 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第6期867-870,共4页
To explore the feasibility of extracting aromatic acid products from oxidizing coal, two aromatic acids, trimellitic and [1,1′-biphenyl]-2,2′-dicarboxylic acid, were selected as the solutes, and the extraction equil... To explore the feasibility of extracting aromatic acid products from oxidizing coal, two aromatic acids, trimellitic and [1,1′-biphenyl]-2,2′-dicarboxylic acid, were selected as the solutes, and the extraction equilibrium of the acids were studied with 1-octanol, 50% tributyl phosphate (TBP) in kerosene, and 10% trialkylphosphine oxide (TRPO) in kerosene. The results showed that the degree of extraction of [1,1′-biphenyl]-2,2′-dicarboxylic acid was larger than that of trimellitic acid for all of the solvent, and the extraction capacity with TRPO is more effective than the one with TBP. The extraction behavior of aromatic polyacid is different from that of carboxylic acid, and the reactive extraction function of aromatic acids with TBP and TRPO is not as effective as that of carboxylic acid. 1-octanol could be used to remove [1,1′-biphenyl]-2,2′-dicarboxylic acid from the mixture of trimellitic acid and [1,1′-biphenyl]-2,2′-dicarboxylic acid. Because the weak hydrogen bond association exists between -OH in 1-octanol and -COOH in aromatic acid, the extractive selectivity of [ 1, 1′-biphenyl]-2,2′-dicarboxylic to trimellitic acid depends on the stoichiometric ratio. 展开更多
关键词 trimellitic acid [1 1′-biphenyl]-2 2′-dicarboxylic acid extraction equilibrium 1-octanol TBP and TRPO
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One-pot synthesis of 2-(1-acyloxypentyl)benzoic acids
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作者 Zhen Li Min Yi Hua Zhang Yi Sheng Lai Si Xun Peng 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第8期915-917,共3页
A one-pot synthesis of 2-(1-acyloxypcntyl) benzoic acids by trapping the carboxylatc/alkoxide dianion with acylating reagents following Grignard addition with n-BuMgBr to 2-formylbcnzoic acid was described. Compared... A one-pot synthesis of 2-(1-acyloxypcntyl) benzoic acids by trapping the carboxylatc/alkoxide dianion with acylating reagents following Grignard addition with n-BuMgBr to 2-formylbcnzoic acid was described. Compared with routine synthetic method, this novel procedure has the advantage of convenient operation and higher yields. 展开更多
关键词 One-pot synthesis 3-n-Butyl-1(3H)-isobcnzofuranone 2-(1-Hydroxypcntyl)benzoic acid 2-(1-Acyloxypcntyl)-benzoic acids
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Flotation behavior and adsorption mechanism of(1-hydroxy-2-methyl-2-octenyl) phosphonic acid to cassiterite 被引量:16
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作者 谭鑫 何发钰 +1 位作者 尚衍波 印万忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第9期2469-2478,共10页
The flotation behavior and adsorption mechanism of novel(1-hydroxy-2-methyl-2-octenyl) phosphonic acid(HEPA) to cassiterite were investigated by micro-flotation tests, zeta potential measurements, FTIR determinati... The flotation behavior and adsorption mechanism of novel(1-hydroxy-2-methyl-2-octenyl) phosphonic acid(HEPA) to cassiterite were investigated by micro-flotation tests, zeta potential measurements, FTIR determination and density functional theory(DFT) calculation. The flotation results demonstrated that HEPA exhibited superior collecting performance compared with styrene phosphonic acid(SPA). The cassiterite recovery maintained above 90% over a wide pH range of 2-9 with 50 mg/L HEPA. The results of zeta potential measurement and FTIR detection indicated that the adsorption of HEPA onto cassiterite was mainly attributed to the chemisorption between HEPA monoanions and Sn species on mineral surfaces. The DFT calculation results demonstrated that HEPA monoanions owned higher HOMO energy and exhibited a better affinity to cassiterite than SPA, which provided very clear evidence for the stronger collecting power of HEPA presented in floatation test and zeta potential measurement. 展开更多
关键词 1-hydroxy-2-methyl-2-octenyl) phosphonic acid CASSITERITE adsorption FLOTATION density functional theory
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Chlorogenic Acid Maintains Glucose Homeostasis through Modulating the Expression of SGLT-1,GLUT-2,and PLG in Different Intestinal Segments of Sprague-Dawley Rats Fed a High-Fat Diet 被引量:13
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作者 PENG Bing Jie ZHU Qi +2 位作者 ZHONG Ying Li XU Shi Hao WANG Zheng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第12期894-903,共10页
Objective To reveal the effects and related mechanisms of chlorogenic acid(CGA)on intestinal glucose homeostasis.Methods Forty male Sprague-Dawley rats were randomly and equally divided into four groups:normal chow(NC... Objective To reveal the effects and related mechanisms of chlorogenic acid(CGA)on intestinal glucose homeostasis.Methods Forty male Sprague-Dawley rats were randomly and equally divided into four groups:normal chow(NC),high-fat diet(HFD),HFD with low-dose CGA(20 mg/kg,HFD-LC),and HFD with high-dose CGA(90 mg/kg,HFD-HC).The oral glucose tolerance test was performed,and fast serum insulin(FSI)was detected using an enzyme-linked immunosorbent assay.The m RNA expression levels of glucose transporters(Sglt-1 and Glut-2)and proglucagon(Plg)in different intestinal segments(the duodenum,jejunum,ileum,and colon)were analyzed using quantitative real-time polymerase chain reaction.SGLT-1 protein and the morphology of epithelial cells in the duodenum and jejunum was localized by using immunofluorescence.Results At both doses,CGA ameliorated the HFD-induced body weight gain,maintained FSI,and increased postprandial 30-min glucagon-like peptide 1 secretion.High-dose CGA inhibited the HFD-induced elevation in Sglt-1 expression.Both CGA doses normalized the HFD-induced downregulation of Glut-2 and elevated the expression of Plg in all four intestinal segments.Conclusion An HFD can cause a glucose metabolism disorder in the rat intestine and affect body glucose homeostasis.CGA can modify intestinal glucose metabolism by regulating the expression of intestinal glucose transporters and Plg,thereby controlling the levels of blood glucose and insulin to maintain glucose homeostasis. 展开更多
关键词 Chlorogenic acid High-fat diet INTESTINE Glucose homeostasis SGLT-1 GLUT-2 PLG GLP-1
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Sphingosine kinase 1 is upregulated with lysophosphatidic acid receptor 2 in human colorectal cancer 被引量:6
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作者 Dai Shida Satoru Inoue +3 位作者 Yuki Yoshida Atsushi Kodaka Tsutomu Tsuji Makoto Tsuiji 《World Journal of Gastroenterology》 SCIE CAS 2016年第8期2503-2511,共9页
AIM: To examine the expression of SphK1, an oncogenic kinase that produces sphingosine 1-phosphate (S1P), and its correlation with the expression of LPAR2, a major lysophosphatidic acid (LPA) receptor overexpressed in... AIM: To examine the expression of SphK1, an oncogenic kinase that produces sphingosine 1-phosphate (S1P), and its correlation with the expression of LPAR2, a major lysophosphatidic acid (LPA) receptor overexpressed in various cancers, in human colorectal cancer.METHODS: Real-time reverse-transcription polymerase chain reaction was used to measure the mRNA expression of SphK1, LPAR2, and the three major S1P receptors in 27 colorectal cancer samples and corresponding normal tissue samples. We also examined the correlation between the expression of SphK1 and LPAR2.RESULTS: Colorectal cancer tissue in 22 of 27 patients had higher levels of SphK1 mRNA than in normal tissue. In two-thirds of the samples, SphK1 mRNA expression was more than two-fold higher than in normal tissue. Consistent with previous reports, LPAR2 mRNA expression in 20 of 27 colorectal cancer tissue samples was higher compared to normal tissue samples. Expression profiles of all three major S1P receptors, S1PR1, S1PR2, and S1PR3, varied without any trend, with no significant difference in expression between cancer and normal tissues. A highly significant positive correlation was found between SphK1 and LPAR2 expression [Pearson&#x02019;s correlation coefficient (r) = 0.784 and P &#x0003c; 0.01]. The mRNA levels of SphK1 and LPAR2 did not correlate with TNM stage.CONCLUSION: Our findings suggest that S1P and LPA may play important roles in the development of colorectal cancer via the upregulation of SphK1 and LPAR2, both of which could serve as new therapeutic targets in the treatment of colorectal cancer. 展开更多
关键词 Sphingosine kinase 1 Lysophosphatidic acid receptor 2 CARCINOGENESIS Colorectal cancer Sphingosine 1-phosphate
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Br?nsted acid catalyzed addition of N^1-p-methyl toluenesulfonyl triazole to olefins for the preparation of N^2-alkyl 1,2,3-triazoles with high N^2-selectivity
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作者 石津玮 朱莉莉 +1 位作者 闻建 陈自立 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1222-1226,共5页
An efficient new method has been developed to synthesize N2‐alkyl 1,2,3‐triazole products by tol‐uenesulfonic acid (TsOH) catalyzed addition of N1‐Ts substituted 1,2,3‐triazoles to olefins. The reac‐tions of m... An efficient new method has been developed to synthesize N2‐alkyl 1,2,3‐triazole products by tol‐uenesulfonic acid (TsOH) catalyzed addition of N1‐Ts substituted 1,2,3‐triazoles to olefins. The reac‐tions of monosubstituted and unsubstituted triazole substrates with various olefins, including vinyl esters, are explored. 展开更多
关键词 Bronsted acid catalysis N2-alkyl 1 2 3-triazole N1-toluenesulfonyl triazole Olefin reaction High N2-selectivity
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Crystal Structures and Luminescent Properties of Three Coordination Polymers Based on 2,5-Furandicarboxylic Acid Ligand and 1,10-Phenanthroline 被引量:3
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作者 赵帅 郝学敏 +2 位作者 王浩 伍一波 郭文莉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第1期131-139,共9页
Three new coordination polymers,namely [Zn(FDA)(phen)(H2O)·H2O]n(1),[Cd(HFDA)(phen)2(NO3)](2) and [Cd(FDA)(phen)]n(3)(H2FDA = 2,5-furandicarboxylic acid,phen = 1,10-phenanthroline) have be... Three new coordination polymers,namely [Zn(FDA)(phen)(H2O)·H2O]n(1),[Cd(HFDA)(phen)2(NO3)](2) and [Cd(FDA)(phen)]n(3)(H2FDA = 2,5-furandicarboxylic acid,phen = 1,10-phenanthroline) have been synthesized by the solvothermal method and characterized by elemental analysis,IR,powder X-ray diffraction,thermogravimetric analysis and X-ray single-crystal diffraction analysis.For 1,the neighboring Zn^2+ ions are bridged by FDA2-as linkers to form one-dimensional(1D) chains,and phen ligands are as the terminal ligands.Furthermore,the 1D chains are packed into a three-dimensional(3D) supramolecular structure through hydrogen bonds and π-π interactions.For 2,the H2FDA ligand is partial deprotonation,which is a rare phenomenon among other coordination polymers based on H2FDA.Under the synergetic effect of phen ligands and the partial deprotonation of H2FDA,the structure of 2 is discrete.For 3,the Cd^2+ ions are linked by two carboxylates of FDA^2-ligand to give rise to 1 D zig-zag chains,and phen ligands chelate the Cd^2+ ions like 1.In addition,solid-state luminescent spectra of three coordination polymers were also studied at room temperature. 展开更多
关键词 2 5-furandicarboxylic acid 1 10-phenanthroline crystal structure
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A One-dimensional Cd(Ⅱ)Coordination Polymer Constructed from 1,4-Benzene-dicarboxylic Acid and 3-(2,6-Di(pyrazin-2-yl)pyridin-4-yl)-1H-indole:Synthesis,Structure and Photoluminescence 被引量:2
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作者 谢玲 卢丽萍 朱苗力 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第10期1606-1614,共9页
A new coordination polymer {[Cd(C_(21)H_(14)N_6)(C_8H_4O_4)]·H_2O}_n(1) was synthesized by an elaborate design via the reaction of 3-(2,6-di(pyrazin-2-yl)pyridin-4-yl)-1H-indole(bppi),1,4-benzene-... A new coordination polymer {[Cd(C_(21)H_(14)N_6)(C_8H_4O_4)]·H_2O}_n(1) was synthesized by an elaborate design via the reaction of 3-(2,6-di(pyrazin-2-yl)pyridin-4-yl)-1H-indole(bppi),1,4-benzene-dicarboxylic acid(H2bdc) and cadmium(Ⅱ) nitrate in CH_3OH/H_2O mixed solvents. Complex 1 crystallizes in orthorhombic,space group Ccca with a = 20.012(4),b = 31.881(6),c = 19.808(4) ?,V = 12638(4) ?~3,Z = 16,C_(29)H_(20)CdN_6O_5,M_r = 644.91,D_c = 1.356 g·cm^(-3),μ = 0.735 mm^(-1),F(000) = 5184,GOOF = 1.046,the final R = 0.0405 and wR = 0.1063 for 6870 observed reflections(I 〉 2σ(I)). The Cd(Ⅱ) centre is hepta-coordinated by three N and four O atoms from one bppi terminal ligand and two bdc2– ligands,respectively,displaying a capped trigonal prism geometry. Structure extension gives coordination polymeric chains,in which the bdc2– linkers connect Cd(Ⅱ) cations into a one-dimensional(1D) coordination polymer along the c axis,giving zigzag chains with the Cd···Cd separation of 11.178(1) ?. The adjacent bppi terminal ligands in the chains are anti-periplanar conformation. The three-dimensional(3D) structure is stabilized by π···π stacking and hydrogen-bonding interactions to form a supramolecular self-penetrating network with 1D channels. In 1,there are voids 2999.7 ?~3 with 23.7% of per unit cell volume. Thermal analysis indicates that the framework of 1 is stable until 651 K and the photoluminescence of 1 in the solid shows very weak fluorescence at 382 and 560 nm upon excitation at 310 nm. 展开更多
关键词 1 4-benzenedicarboxylic acid 3-(2 6-di(pyrazin-2-yl)pyridin-4-yl)-1H-indole one-dimensional cadmium(Ⅱ) coordination polymer π···π stacking interactions photoluminescence
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基于酪蛋白寡肽的W_(1)/O/W_(2)双重乳液体系构建及体外模拟消化特性研究 被引量:1
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作者 姚萍 王筠钠 +3 位作者 张书文 逄晓阳 于景华 吕加平 《中国乳品工业》 CAS 北大核心 2024年第1期5-10,16,共7页
酪蛋白寡肽的生理活性取决于其活性物质在胃肠道消化过程中的稳定性。实验以酪蛋白寡肽为芯材,营养较丰富的亲脂性乳化剂磷脂作为外水相(W_(1)/O),亲水性乳化剂磷酸酯双淀粉作为外水相W_(2),制备W_(1)/O/W_(2)双重乳液体系,探究乳化条件... 酪蛋白寡肽的生理活性取决于其活性物质在胃肠道消化过程中的稳定性。实验以酪蛋白寡肽为芯材,营养较丰富的亲脂性乳化剂磷脂作为外水相(W_(1)/O),亲水性乳化剂磷酸酯双淀粉作为外水相W_(2),制备W_(1)/O/W_(2)双重乳液体系,探究乳化条件(高压均质和高压微射流)对双重乳液体系稳定性的影响。并通过体外模拟消化实验探究其在胃肠中的变化,分析消化过程寡肽缓释特性。结果表明,25 MPa压力下乳液的稳定性较好,包封率为95.5%。双重乳液体系能够抵抗胃酶及较低的pH环境,酪蛋白寡肽的包封率>70%。在胰酶作用下随消化时间增加,该体系游离脂肪酸的释放量增加,酪蛋白寡肽的包封率降低,达到酪蛋白寡肽的缓释。 展开更多
关键词 包埋 W_(1)/O/W_(2)双重乳液 体外消化 游离脂肪酸
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新藤黄酸诱导人鼻咽癌细胞CNE-1凋亡以及对p-p38和p-ERK1/2蛋白的影响 被引量:17
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作者 晏烽根 李庆林 《中国药理学通报》 CAS CSCD 北大核心 2011年第3期355-359,共5页
目的探讨新藤黄酸对人鼻咽癌细胞CNE-1凋亡的作用以及对磷酸化p38、p-ERK1/2蛋白的影响。方法倒置显微镜观察新藤黄酸不同时间和不同浓度处理CNE-1细胞形态变化;采用四甲基偶氮唑蓝(MTT)比色法检测不同浓度新藤黄酸(0.25、0.5、1.0、2.0... 目的探讨新藤黄酸对人鼻咽癌细胞CNE-1凋亡的作用以及对磷酸化p38、p-ERK1/2蛋白的影响。方法倒置显微镜观察新藤黄酸不同时间和不同浓度处理CNE-1细胞形态变化;采用四甲基偶氮唑蓝(MTT)比色法检测不同浓度新藤黄酸(0.25、0.5、1.0、2.0、4.0和8.0μmol.L-1)处理24 h、48 h和72 h对人鼻咽癌细胞CNE-1增殖的抑制作用;新藤黄酸作用CNE-1细胞24 h后的IC50为2.34μmol.L-1,再结合倒置显微镜观察的结果故选用2.0μmol.L-1作为药物作用浓度。Annexin V-FITC/PI双染流式细胞仪检测细胞凋亡率,并应用透射电子显微镜检测细胞凋亡形态改变及线粒体损伤;Western blot检测p-p38、p38、ERK1/2和p-ERK1/2蛋白和线粒体凋亡相关蛋白Cytochrome C和Caspase-3蛋白的表达。结果新藤黄酸对人鼻咽癌细胞CNE-1生长和增殖有抑制作用,并随着新藤黄酸浓度的增加或作用时间的延长细胞活力明显下降。通过电镜可见2.0μmol.L-1新藤黄酸作用CNE-1细胞后细胞体积皱缩变圆,细胞核发生典型核染色质固缩等细胞凋亡形态学的变化;与control组相比包括对线粒体的损伤。Western blot表明p-p38蛋白表达有所上调,特别是在短时间(120 min)内,p-ERK1/2蛋白表达呈现时间依赖性下降;而p38和ERK1/2表达则基本不变。Cytochrome C和Caspase-3蛋白表达也呈现时间依赖性增加。结论新藤黄酸能诱导人鼻咽癌细胞CNE-1凋亡,增强Cytochrome C和Caspase-3蛋白表达,同时对p-p38和p-ERK1/2蛋白也有影响。 展开更多
关键词 新藤黄酸 CNE-1细胞 细胞凋亡 P-P38 P-ERK1/2 p38 ERK1/2
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丹参多酚酸对心房颤动大鼠心肌组织中VCAM-1和ICAM-1水平及ERK1/2-NF-κB信号通路的影响 被引量:11
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作者 李小兵 王旭 +5 位作者 吕瑛 黄建成 李红英 王军 张会军 苏振宇 《吉林大学学报(医学版)》 CAS CSCD 北大核心 2020年第5期1004-1010,I0004,I0005,共9页
目的:研究丹参多酚酸对心房颤动(房颤)大鼠心肌组织中血管细胞黏附分子1(VCAM-1)和细胞间黏附分子1(ICAM-1)水平及细胞外信号调节酶1/2-核转录因子-κB(ERK1/2-NF-κB)信号通路的影响,探讨丹参多酚酸防治房颤的可能机制。方法:48只SD大... 目的:研究丹参多酚酸对心房颤动(房颤)大鼠心肌组织中血管细胞黏附分子1(VCAM-1)和细胞间黏附分子1(ICAM-1)水平及细胞外信号调节酶1/2-核转录因子-κB(ERK1/2-NF-κB)信号通路的影响,探讨丹参多酚酸防治房颤的可能机制。方法:48只SD大鼠随机分为对照组、房颤组和丹参多酚酸组,每组16只。舌下静脉注射氯化钙-乙酰胆碱混合液建立房颤大鼠模型。丹参多酚酸组大鼠用丹参多酚酸(4 mg·kg^-1·d^-1)灌胃,对照组和房颤组大鼠用等量生理盐水灌胃,每天1次,共4周。采用苏木精-伊红(HE)染色观察大鼠心肌组织病理形态表现,Masson染色观察心肌纤维化情况,免疫组织化学染色检测各组大鼠心肌组织中基质金属蛋白酶2(MMP-2)和基质金属蛋白酶9(MMP-9)蛋白表达水平,Western blotting法检测各组大鼠心肌组织中VCAM-1、ICAM-1、ERK1/2、磷酸化细胞外调节蛋白激酶1/2(p-ERK1/2)、NF-κB和磷酸化核转录因子κB(p-NF-κB)蛋白表达水平。结果:HE染色,对照组大鼠心肌细胞未见明显异常;房颤组大鼠心肌组织间质增多,可见炎性细胞浸润;与房颤组比较,丹参多酚酸组大鼠心肌组织间质稍多,炎性细胞浸润不明显。Masson染色,对照组大鼠心肌间质胶原纤维正常;房颤组大鼠心肌间质胶原纤维明显增多;与房颤组比较,丹参多酚酸组大鼠心肌间质胶原纤维较房颤组明显减少。与对照组比较,房颤组和丹参多酚酸组大鼠心肌组织中MMP-2、MMP-9、VCAM-1、ICAM-1、p-ERK1/2和p-NF-κB蛋白表达水平升高(P<0.05);与房颤组比较,丹参多酚酸组大鼠心肌组织中MMP-2、MMP-9、VCAM-1、ICAM-1、p-ERK1/2和p-NF-κB蛋白表达水平降低(P<0.05)。房颤组大鼠心肌组织中MMP-2和MMP-9蛋白表达水平与VCAM-1(r=0.435,P<0.01;r=0.512,P<0.01)和ICAM-1(r=0.486,P<0.01;r=0.579,P<0.01)蛋白表达水平呈正相关关系。结论:丹参多酚酸可通过抑制房颤大鼠心房组织ERK1/2-NF-κB信号通路激活,降低VCAM-1和ICAM-1水平,抑制心肌纤维化,从而发挥对房颤的治疗作用。 展开更多
关键词 丹参多酚酸 心房颤动 血管细胞黏附分子1 细胞间黏附分子1 细胞外信号调节酶1/2-核转录因子-κB信号通路 基质金属蛋白酶
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Metal-organic frameworks derived from divalent metals and 4-(1H-1, 2, 4-triazol-1-yl)benzoic acid
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作者 Jia Li Gao Zhang +3 位作者 Yan-Tao Li Xin Wang Jian-Qi Zhu Yun-Qi Tian 《Open Journal of Inorganic Chemistry》 2012年第3期58-66,共9页
Two inorganic-organic coordination polymers, [Cd(TBA)2]·3H2O (1) and [Cu(TBA)2]·2H2O (2) have been synthesized by reaction of the metal ions of Cd(II) and Cu(II) with the ligand HTBA [HTBA = 4- (1H-1, 2, 4-t... Two inorganic-organic coordination polymers, [Cd(TBA)2]·3H2O (1) and [Cu(TBA)2]·2H2O (2) have been synthesized by reaction of the metal ions of Cd(II) and Cu(II) with the ligand HTBA [HTBA = 4- (1H-1, 2, 4-triazol-1-yl)benzoic acid] under solvothermal condition. The compounds were characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy, X-ray powder diffraction (XRPD), and thermo gravimetric analysis (TGA). The structural analyses reveal the two independent polymers exhibit different structures. Complex 1 exhibits a 3D framework with 1D channels, and complex 2 shows a 2-fold interpenetrating 3D diamond net. 展开更多
关键词 COORDINATION POLYMERS 4-(1H-1 2 4-triazol-1-yl)benzoic acid Crystal Structure CADMIUM Copper
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HIV-1 Env gp120 C2V5 Potential N-Linked Glycosylation Site(s) (PNGs) Variations and Amino Acid Length Polymorphisms among Infected Family Members
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作者 Duri Kerina Felicity Zvanyadza Gumbo +5 位作者 Knut Ivans Kristiansen Munyaradzi Paul Mapingure Simba Rusakaniko Mike Zvavahera Chirenje Babill Stray-Pedersen Fredrik Müller 《Advances in Infectious Diseases》 2011年第1期1-13,共13页
Objective: To ascertain the role of HIV-1 gp120 env PNGs variations and sequence length polymorphism following transmission events as possible supporting forensic evidence to determine directionality of HIV transmissi... Objective: To ascertain the role of HIV-1 gp120 env PNGs variations and sequence length polymorphism following transmission events as possible supporting forensic evidence to determine directionality of HIV transmission. Method: An observational study of HIV-1 infected family members, where median and range values of the amino acid lengths and PNGs for the genotyped C2V5 region were calculated. Wilcoxon rank-sum test was used to determine differences in these parameters between different family members. Results: For heterosexual transmission, two mothers had longer C3 sequences relative to that of their spouses;p=0.006 and=0.025 whilst the opposite was observed for one mother, p = 0.028. No clear trends were observed for PNGs. Index children had longer C2V5 amino acid sequences compared to their mothers p = 0.013, 0.040, 0.043 for families 205, 375, 567 respectively. Second siblings “V4 and V5 sequences were generally shorter relative to the maternal ones p = 0.039 and 0.028, respectively. Adults had longer V3 amino acid sequences compared to children;p = 0.018. Similar trends were also observed regarding PNGs within the entire C2V5 region, C3 and V4 sub-regions;p= 0.0025, 0.005 and 0.008, respectively. First siblings’ C2V5 and C3 sequence lengths were significantly longer relative to those of the second siblings;p = 0.005 and 0.007, respectively. Conclusion: Our results are suggestive that HIV-1 env C2V5 amino acid length polymorphism and PNGs tend to increase with age and HIV disease progression. Though sensitive and should be cautiously handled, it is tempting to propose the direc-tionality of the HIV transmission events with respect to C3 sequence length polymorphisms. Correlating HIV-1 env C2V5 amino acid length polymorphism and age of infection may be the first step towards a possible valuable piece of forensic evidence which may be useful in criminalisation of willful HIV infections. However, bigger studies are war-ranted to substantiate the authenticity of this potentially useful application. 展开更多
关键词 HIV-1 Env120 C2V5 GLYCOSYLATION Amino acid Length Polymorphism PARENT to Child Transmission
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Effects of P2Y_1 receptor on glial fibrillary acidic protein and glial cell line-derived neurotrophic factor production of astrocytes under ischemic condition and the related signaling pathways 被引量:3
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作者 孙景军 刘颖 叶诸榕 《Neuroscience Bulletin》 SCIE CAS CSCD 2008年第4期231-243,共13页
Objective The present study aimed to explore the role of P2Y1 receptor in glial fibrillary acidic protein (GFAP) production and glial cell line-derived neurotrophic factor (GDNF) secretion of astrocytes under isch... Objective The present study aimed to explore the role of P2Y1 receptor in glial fibrillary acidic protein (GFAP) production and glial cell line-derived neurotrophic factor (GDNF) secretion of astrocytes under ischemic insult and the related signaling pathways. Methods Using transient right middle cerebral artery occlusion (tMCAO) and oxygen-glucose-serum deprivation for 2 h as the model of ischemic injury in vivo and in vitro, immunofluorescence, quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR), Western blotting, enzyme linked immunosorbent assay (ELISA) were used to investigate location of P2Y1 receptor and GDNF, the expression of GFAP and GDNF, and the changes of signaling molecules. Results Blockage of P2Y1 receptor with the selective antagonist N^6-methyl-2′-deoxyadenosine 3′,5′-bisphosphate diammonium (MRS2179) reduced GFAP production and increased GDNF production in the antagonist group as compared with simple ischemic group both in vivo and in vitro. Oxygen-glucose-serum deprivation and blockage of P2Y1 receptor caused elevation of phosphorylated Akt and cAMP response element binding protein (CREB), and reduction of phosphorylated Janus kinase2 (JAK2) and signal transducer and activator of transcription3 (STAT3, Ser727). After blockage of P2Y1 receptor and deprivation of oxygen-glucose-serum, AG490 (inhibitor of JAK2) reduced phosphorylation of STAT3 (Ser727) as well as expression of GFAP; LY294002, an inhibitor of phosphatidylinositol 3-kinase (PI3-K), decreased phosphorylation of Akt and CREB; the inhibitor of mitogen-activated protein kinase kinase 1/2 (MEK 1/2) U0126, an important molecule of Ras/extracellular signal- regulated kinase (ERK) signaling pathway, decreased the phosphorylation of JAK2, STAT3 (Ser727), Akt and CREB. Conclusion These results suggest that P2Y1 receptor plays a role in the production of GFAP and GDNF in astrocytes under transient ischemic condition and the related signaling pathways may be JAK2/STAT3 and PI3-K/Akt/CREB, respectively, and that crosstalk probably exists between them. 展开更多
关键词 P2Y1 receptor GLIOSIS glial fibrillary acidic protein glial cell line-derived neurotrophic factor PI3-K/Akt/CREB JAK2/STAT3 Ras/ERK
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固定化脂肪酶ANL-MARE催化酸解合成1-油酸-2-棕榈酸-3-亚油酸甘油三酯
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作者 康梦 何家强 +7 位作者 冯孔龙 黄早成 李一峰 苗建银 符姜燕 朱泽榕 刘果 曹庸 《现代食品科技》 CAS 北大核心 2024年第2期109-119,共11页
1-油酸-2-棕榈酸-3-亚油酸甘油三酯(OPL)是人乳中主要的脂质组成,为满足婴幼儿配方食品母乳化需求,该试验探究了新型固定化脂肪酶ANL-MARE催化制备OPL的方法。试验成功制备和表征了固定化酶ANLMARE,并以ANL-MARE为生物催化剂,建立了一... 1-油酸-2-棕榈酸-3-亚油酸甘油三酯(OPL)是人乳中主要的脂质组成,为满足婴幼儿配方食品母乳化需求,该试验探究了新型固定化脂肪酶ANL-MARE催化制备OPL的方法。试验成功制备和表征了固定化酶ANLMARE,并以ANL-MARE为生物催化剂,建立了一种用三棕榈酸甘油三酯(PPP)、油酸(OA)和亚油酸(LA)高效酶催化制备富含OPL结构脂的方法。经单因素和响应面试验优化,获得OPL最优合成工艺为:PPP与总脂肪酸的摩尔比1:14.27,OA与LA摩尔比为1:0.76,脂肪酶添加量12.70%,反应温度50℃,反应4 h,此条件下产物中OPL相对含量为47.93%,2位棕榈酸(sn-2 PA)占总棕榈酸(PA)的质量分数(sn-2 PA相对含量)为71.69%。此外,固定化酶ANL-MARE与商业脂肪酶相比,表现出较好的催化合成OPL的活性。综上所述,固定化酶ANL-MARE具有催化制备OPL结构脂的重大潜力,为人乳脂替代脂的高效制备提供了新策略和理论基础。 展开更多
关键词 1-油酸-2-棕榈酸-3-亚油酸甘油三酯 酶促酸解法 固定化脂肪酶 ANL-MARE 工艺优化
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3-{2-([5,6]-咪唑-1,10-邻菲咯啉)]}-3′-甲酸-2,2’-联吡啶的合成和晶体结构 被引量:2
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作者 陈明华 祝黔江 +1 位作者 薛赛凤 陶朱 《分子科学学报》 CAS CSCD 北大核心 2010年第1期28-32,共5页
以1,10-邻菲咯啉为原料,经三步反应生成了标题化合物,化合物经1H NMR,MS和X-射线单晶衍射表征.结果表明,化合物晶体为单斜晶系,空间群,P21/c,a=1.24828(16)nm,b=1.18534(15)nm,c=1.37542(16)nm,α=90.00°,β=109.268(4)°,γ=9... 以1,10-邻菲咯啉为原料,经三步反应生成了标题化合物,化合物经1H NMR,MS和X-射线单晶衍射表征.结果表明,化合物晶体为单斜晶系,空间群,P21/c,a=1.24828(16)nm,b=1.18534(15)nm,c=1.37542(16)nm,α=90.00°,β=109.268(4)°,γ=90.00°,V=1.9211(4)nm^(3),Z=4,Mr=418.41,Dc=1.440g.cm^(-3),μ=0.097mm^(-1),F(000)=856,R_(1)=0.0633,wR_(2)=0.1803.CCDC:728109. 展开更多
关键词 1 10-邻菲咯啉 1 10-邻菲咯啉-5 6-二酮 1 10-邻菲咯啉取代半苷脲 3-{2-([5 6]-咪唑-1 10-邻菲咯啉)]}-3’-甲酸-2 2’-联吡啶 晶体结构
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薯蓣皂苷通过GSK3β/Nrf2/HO-1通路改善尿酸诱导的HK-2细胞氧化应激损伤的作用及机制研究
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作者 周丽娟 张伟梁 +3 位作者 刘瑞琦 冯嘉树 黄颖娟 伍新林 《中药新药与临床药理》 CAS CSCD 北大核心 2024年第3期342-348,共7页
目的探讨薯蓣皂苷(dioscin)对尿酸(uric acid,UA)诱导的人肾小管上皮细胞(HK-2)氧化应激损伤的影响及分子机制。方法将HK-2细胞分为正常组、模型组(尿酸刺激造模)、条件对照组(尿酸+DMSO)和薯蓣皂苷组(尿酸+薯蓣皂苷)。通过尿酸诱导HK-... 目的探讨薯蓣皂苷(dioscin)对尿酸(uric acid,UA)诱导的人肾小管上皮细胞(HK-2)氧化应激损伤的影响及分子机制。方法将HK-2细胞分为正常组、模型组(尿酸刺激造模)、条件对照组(尿酸+DMSO)和薯蓣皂苷组(尿酸+薯蓣皂苷)。通过尿酸诱导HK-2细胞氧化应激损伤模型;采用CCK-8法检测细胞活力,流式细胞技术检测细胞活性氧(ROS)水平,Real-time PCR法检测糖原合成激酶3(GSK3β)、核转录因子红系2相关因子2(Nrf2)和血红素加氧酶1(HO-1)在mRNA水平的表达,Western Blot法检测GSK3β、磷酸化糖原合成激酶3(p-GSK3β)、Nrf2及HO-1在蛋白水平的表达。结果经尿酸刺激后,HK-2细胞的活力明显下降,ROS水平明显升高(均P<0.001)。经薯蓣皂苷治疗后,HK-2细胞的活力增加,ROS水平明显降低(均P<0.001)。在蛋白及mRNA水平上,尿酸刺激后Nrf2和HO-1的表达均下降,薯蓣皂苷干预后Nrf2和HO-1表达均明显增加(均P<0.001)。在蛋白水平上,模型组细胞p-GSK3β/GSK3β比值较正常组明显下降,经薯蓣皂苷干预后p-GSK3β/GSK3β比值升高(均P<0.001)。结论薯蓣皂苷可能是通过促进GSK3β的磷酸化,激活Nrf2/HO-1通路,从而缓解尿酸诱导的HK-2细胞氧化应激损伤。 展开更多
关键词 薯蓣皂苷 尿酸 HK-2细胞 GSK3β/Nrf2/HO-1通路 氧化应激
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Regulating effect of glycyrrhetinic acid on bronchial asthma smooth muscle proliferation and apoptosis as well as inflammatory factor expression through ERK1/2 signaling pathway 被引量:18
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作者 Tao Zhang Jia-Yi Liao +1 位作者 Li Yu Guo-Sheng Liu 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第12期1172-1176,共5页
Objective: To study the influence of glycyrrhetinic acid(GA) on bronchial asthma(BA)smooth muscle proliferation and apoptosis as well as inflammatory factor expression and its molecular mechanism.Methods: Male SD guin... Objective: To study the influence of glycyrrhetinic acid(GA) on bronchial asthma(BA)smooth muscle proliferation and apoptosis as well as inflammatory factor expression and its molecular mechanism.Methods: Male SD guinea pigs were selected and made into asthma models, bronchial asthma smooth muscle cells were cultured and divided into BA group, GA group and GA + LM group that were treated with serum-free RPMI1640 culture medium, serumfree RPMI1640 culture medium containing 50 ng/mL glycyrrhetinic acid, serum-free RPMI1640 culture medium containing 50 ng/mL glycyrrhetinic acid and 100 ng/mL LM22B-10 respectively; normal guinea pigs were collected and bronchial smooth muscle cells were cultured as control group. The cell proliferation activity as well as the expression of proliferation and apoptosis genes, inflammatory factors and p-ERK1/2 was determined.Results: Proliferation activity value and m RNA expression of Bcl-2, TNF-α, IL-4, IL-6,YKL-40, protein expression of p-ERK1/2 of airway smooth muscle cell in BA group were significantly higher than those of control group while m RNA expression levels of Bax,caspase-9 as well as caspase-3 were significantly lower than that of control group(P < 0.05); proliferation activity value and m RNA expression of Bcl-2, TNF-α, IL-4, IL-6, YKL-40, protein expression of p-ERK1/2 of airway smooth muscle cell in GA group were significantly lower than those of BA group(P < 0.05) while the m RNA expression levels of Bax, caspase-9 as well as caspase-3 were significantly higher than those of BA group(P < 0.05); proliferation activity value and m RNA expression of Bcl-2, TNF-α, IL-4, IL-6, YKL-40 of airway smooth muscle cell in GA + LM group were significantly higher than those of GA group(P < 0.05) while m RNA expression levels of Bax, caspase-9 as well as caspase-3 were significantly lower that of GA group(P < 0.05).Conclusion: GA can inhibit the proliferation of bronchial smooth muscle cells and reduce the expression of inflammatory factors by inhibiting the phosphorylation of ERK1/2. 展开更多
关键词 Bronchial asthma Glycyrrhetinic acid Extracellular signal-regulated kinase 1/2 Apoptosis Inflammatory factors
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Gambogic acid induces mitochondria-dependent apoptosis by modulation of Bcl-2 and Bax in mantle cell lymphoma JeKo-1 cells 被引量:18
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作者 Jingyan Xu Min Zhou +7 位作者 Jian Ouyang Jing Wang Qiguo Zhang Yong Xu Yueyi Xu Qian Zhang Xihui Xu Hui Zeng 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2013年第2期183-191,共9页
Objective: To study the mechanisms in gambogic acid (GA) -induced JeKo-1 human Mantle Cell Lymphoma cell apoptosis in vitro. Methods: The proliferation of GA-treated JeKo-1 cells was measured by CCK-8 assay and Ki... Objective: To study the mechanisms in gambogic acid (GA) -induced JeKo-1 human Mantle Cell Lymphoma cell apoptosis in vitro. Methods: The proliferation of GA-treated JeKo-1 cells was measured by CCK-8 assay and Ki-67 immunocytochemical detection. Apopt0sis, cell cycle and mitochondrial membrane potential were measured by flow cytometric analysis. Caspase-3, -8 and -9 were detected by colorimetric assay. Bcl-2 and Bax were analyzed by Western blotting. Results: GA inhibited cell growth in a time- and dose- dependent manner. GA induces apoptosis in JeKo- 1 cells but not in normal bone marrow cells, which was involved in reducing the membrane potential of mitochondria, activating caspases-3, -8 and -9 and decreasing the ratio of Bd-2 and Bax without cell cycle arresting. Conclusions: GA induced apoptosis in human MCL JeKo-1 cells by regulating Bcl-2/Bax and activating caspase-3, -8 and -9 via mitochondrial pathway without affecting cell cycle. 展开更多
关键词 Gambogic acid JeKo-1 cells cell cycle arrest apoptosis membrane potential of mitochondria caspase-3 CASPASE-8 caspase-9 BAX BCL-2
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