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MicroRNA-502-3p regulates GABAergic synapse function in hippocampal neurons 被引量:3
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作者 Bhupender Sharma Melissa MTorres +2 位作者 Sheryl Rodriguez Laxman Gangwani Subodh Kumar 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2698-2707,共10页
Gamma-aminobutyric acid(GABA)ergic neurons,the most abundant inhibitory neurons in the human brain,have been found to be reduced in many neurological disorders,including Alzheimer's disease and Alzheimer's dis... Gamma-aminobutyric acid(GABA)ergic neurons,the most abundant inhibitory neurons in the human brain,have been found to be reduced in many neurological disorders,including Alzheimer's disease and Alzheimer's disease-related dementia.Our previous study identified the upregulation of microRNA-502-3p(miR-502-3p)and downregulation of GABA type A receptor subunitα-1 in Alzheimer's disease synapses.This study investigated a new molecular relationship between miR-502-3p and GABAergic synapse function.In vitro studies were perfo rmed using the mouse hippocampal neuronal cell line HT22 and miR-502-3p agomiRs and antagomiRs.In silico analysis identified multiple binding sites of miR-502-3p at GABA type A receptor subunitα-1 mRNA.Luciferase assay confirmed that miR-502-3p targets the GABA type A receptor subunitα-1 gene and suppresses the luciferase activity.Furthermore,quantitative reve rse transcription-polymerase chain reaction,miRNA in situ hybridization,immunoblotting,and immunostaining analysis confirmed that overexpression of miR-502-3p reduced the GABA type A receptor subunitα-1 level,while suppression of miR-502-3p increased the level of GABA type A receptor subunitα-1 protein.Notably,as a result of the overexpression of miR-502-3p,cell viability was found to be reduced,and the population of necrotic cells was found to be increased.The whole cell patch-clamp analysis of human-GABA receptor A-α1/β3/γ2L human embryonic kidney(HEK)recombinant cell line also showed that overexpression of miR-502-3p reduced the GABA current and overall GABA function,suggesting a negative correlation between miR-502-3p levels and GABAergic synapse function.Additionally,the levels of proteins associated with Alzheimer s disease were high with miR-502-3p overexpression and reduced with miR-502-3p suppression.The present study provides insight into the molecular mechanism of regulation of GABAergic synapses by miR-502-3p.We propose that micro-RNA,in particular miR-502-3p,could be a potential therapeutic to rget to modulate GABAergic synapse function in neurological disorders,including Alzheimer's disease and Alzheimer's diseaserelated dementia. 展开更多
关键词 Alzheimer's disease GABAergic synapse gamma-aminobutyric acid type A receptor subunitα-1(GABRα1) microRNA-502-3p(miR-502-3p) miRNA in situ hybridization pATCH-CLAMp
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18β-glycyrrhetinic acid inhibits proliferation of gastric cancer cells through regulating the miR-345-5p/TGM2 signaling pathway 被引量:3
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作者 Xia Li Xiao-Ling Ma +8 位作者 Yi Nan Yu-Hua Du Yi Yang Dou-Dou Lu Jun-Fei Zhang Yan Chen Lei Zhang Yang Niu Ling Yuan 《World Journal of Gastroenterology》 SCIE CAS 2023年第23期3622-3644,共23页
BACKGROUND Gastric cancer(GC)is a common gastrointestinal malignancy worldwide.Based on cancer-related mortality,the current prevention and treatment strategies for GC still show poor clinical results.Therefore,it is ... BACKGROUND Gastric cancer(GC)is a common gastrointestinal malignancy worldwide.Based on cancer-related mortality,the current prevention and treatment strategies for GC still show poor clinical results.Therefore,it is important to find effective drug treatment targets.AIM To explore the molecular mechanism of 18β-glycyrrhetinic acid(18β-GRA)regulating the miR-345-5p/TGM2 signaling pathway to inhibit the proliferation of GC cells.METHODS CCK-8 assay was used to determine the effect of 18β-GRA on the survival rate of GES-1 cells and AGS and HGC-27 cells.Cell cycle and apoptosis were detected by flow cytometry,cell migration was detected by a wound healing assay,the effect of 18β-GRA on subcutaneous tumor growth in BALB/c nude mice was investigated,and the cell autophagy level was determined by MDC staining.TMT proteomic analysis was used to detect the differentially expressed autophagy-related proteins in GC cells after 18β-GRA intervention,and then the protein-protein interaction was predicted using STRING(https://string-db.org/).MicroRNAs(miRNAs)transcriptome analysis was used to detect the miRNA differential expression profile,and use miRBase(https://www.mirbase/)and TargetScan(https://www.targetscan.org/)to predict the miRNA and complementary binding sites.Quantitative real-time polymerase chain reaction was used to detect the expression level of miRNA in 18β-GRA treated cells,and western blot was used to detect the expression of autophagy related proteins.Finally,the effect of miR-345-5p on GC cells was verified by mir-345-5p overexpression.RESULTS 18β-GRA could inhibit GC cells viability,promote cell apoptosis,block cell cycle,reduce cell wound healing ability,and inhibit the GC cells growth in vivo.MDC staining results showed that 18β-GRA could promote autophagy in GC cells.By TMT proteomic analysis and miRNAs transcriptome analysis,it was concluded that 18β-GRA could down-regulate TGM2 expression and up-regulate miR-345-5p expression in GC cells.Subsequently,we verified that TGM2 is the target of miR-345-5p,and that overexpression of miR-345-5p significantly inhibited the protein expression level of TGM2.Western blot showed that the expression of autophagy-related proteins of TGM2 and p62 was significantly reduced,and LC3II,ULK1 and AMPK expression was significantly increased in GC cells treated with 18β-GRA.Overexpression of miR-345-5p not only inhibited the expression of TGM2,but also inhibited the proliferation of GC cells by promoting cell apoptosis and arresting cell cycle.CONCLUSION 18β-GRA inhibits the proliferation of GC cells and promotes autophagy by regulating the miR-345-5p/TGM2 signaling pathway. 展开更多
关键词 18β-glycyrrhetinic acid Gastric cancer MiR-345-5p TGM2 pROLIFERATION AUTOpHAGY
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18β-glycyrrhetinic acid promotes gastric cancer cell autophagy and inhibits proliferation by regulating miR-328-3p/signal transducer and activator of transcription 3
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作者 Yi Yang Yi Nan +7 位作者 Yu-Hua Du Shi-Cong Huang Dou-Dou Lu Jun-Fei Zhang Xia Li Yan Chen Lei Zhang Ling Yuan 《World Journal of Gastroenterology》 SCIE CAS 2023年第27期4317-4333,共17页
BACKGROUND Gastric cancer(GC)is one of the most common cancer types worldwide,and its prevention and treatment methods have garnered much attention.As the active ingredient of licorice,18β-glycyrrhetinic acid(18β-GR... BACKGROUND Gastric cancer(GC)is one of the most common cancer types worldwide,and its prevention and treatment methods have garnered much attention.As the active ingredient of licorice,18β-glycyrrhetinic acid(18β-GRA)has a variety of pharmacological effects.The aim of this study was to explore the effective target of 18β-GRA in the treatment of GC,in order to provide effective ideas for the clinical prevention and treatment of GC.AIM To investigate the mechanism of 18β-GRA in inhibiting cell proliferation and promoting autophagy flux in GC cells.METHODS Whole transcriptomic analyses were used to analyze and screen differentially expressed microRNAs(miRNAs)in GC cells after 18β-GRA intervention.Lentivirus-transfected GC cells and the Cell Counting Kit-8 were used to detect cell proliferation ability,cell colony formation ability was detected by the clone formation assay,and flow cytometry was used to detect the cell cycle and apoptosis.A nude mouse transplantation tumor model of GC cells was constructed to verify the effect of miR-328-3p overexpression on the tumorigenicity of GC cells.Tumor tissue morphology was observed by hematoxylin and eosin staining,and microtubule-associated protein light chain 3(LC3)expression was detected by immunohistochemistry.TransmiR,STRING,and miRWalk databases were used to predict the relationship between miR-328-3p and signal transducer and activator of transcription 3(STAT3)-related information.Expression of STAT3 mRNA and miR-328-3p was detected by quantitative polymerase chain reaction(qPCR)and the expression levels of STAT3,phosphorylated STAT3(p-STAT3),and LC3 were detected by western blot analysis.The targeted relationship between miR-328-3p and STAT3 was detected using the dual-luciferase reporter gene system.AGS cells were infected with monomeric red fluorescent protein-green fluorescent protein-LC3 adenovirus double label.LC3 was labeled and autophagy flow was observed under a confocal laser microscope.RESULTS The expression of miR-328-3p was significantly upregulated after 18β-GRA intervention in AGS cells(P=4.51E-06).Overexpression of miR-328-3p inhibited GC cell proliferation and colony formation ability,arrested the cell cycle in the G0/G1 phase,promoted cell apoptosis,and inhibited the growth of subcutaneous tumors in BALB/c nude mice(P<0.01).No obvious necrosis was observed in the tumor tissue in the negative control group(no drug intervention or lentivirus transfection)and vector group(the blank vector for lentivirus transfection),and more cells were loose and necrotic in the miR-328-3p group.Bioinformatics tools predicted that miR-328-3p has a targeting relationship with STAT3,and STAT3 was closely related to autophagy markers such as p62.After overexpressing miR-328-3p,the expression level of STAT3 mRNA was significantly decreased(P<0.01)and p-STAT3 was downregulated(P<0.05).The dual-luciferase reporter gene assay showed that the luciferase activity of miR-328-3p and STAT33’untranslated regions of the wild-type reporter vector group was significantly decreased(P<0.001).Overexpressed miR-328-3p combined with bafilomycin A1(Baf A1)was used to detect the expression of LC3 II.Compared with the vector group,the expression level of LC3 II in the overexpressed miR-328-3p group was downregulated(P<0.05),and compared with the Baf A1 group,the expression level of LC3 II in the overexpressed miR-328-3p+Baf A1 group was upregulated(P<0.01).The expression of LC3 II was detected after intervention of 18β-GRA in GC cells,and the results were consistent with the results of miR-328-3p overexpression(P<0.05).Additional studies showed that 18β-GRA promoted autophagy flow by promoting autophagosome synthesis(P<0.001).qPCR showed that the expression of STAT3 mRNA was downregulated after drug intervention(P<0.05).Western blot analysis showed that the expression levels of STAT3 and p-STAT3 were significantly downregulated after drug intervention(P<0.05).CONCLUSION 18β-GRA promotes the synthesis of autophagosomes and inhibits GC cell proliferation by regulating the miR-328-3p/STAT3 signaling pathway. 展开更多
关键词 18β-glycyrrhetinic acid miR-328-3p Signal transducer and activator of transcription 3 Cell proliferation Autophagy flow
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Effects of ω-3 fatty acids on toll-like receptor 4 and nuclear factor-κB p56 in lungs of rats with severe acute pancreatitis 被引量:12
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作者 Bin Wang Xiao-Wei Wu +4 位作者 Mei-Xia Guo Min-Li Li Xiao-Bing Xu Xin-Xin Jin Xiao-Hua Zhang 《World Journal of Gastroenterology》 SCIE CAS 2016年第44期9784-9793,共10页
AIM To determine the effects of ω-3 fatty acids(ω-3FA) on the toll-like receptor 4(TLR4)/nuclear factor κB p56(NF-κBp56) signal pathway in the lungs of rats with severe acute pancreatitis(SAP).METHODS A total of 5... AIM To determine the effects of ω-3 fatty acids(ω-3FA) on the toll-like receptor 4(TLR4)/nuclear factor κB p56(NF-κBp56) signal pathway in the lungs of rats with severe acute pancreatitis(SAP).METHODS A total of 56 Sprague-Dawley rats were randomly divided into 4 groups: control group, SAP-saline group, SAP-soybean oil group and SAP-ω-3FA group. SAP was induced by the retrograde infusion of sodium taurocholate into the pancreatic duct. The expression of TLR4 and NF-κBp56 in the lungs was evaluated by immunohistochemistry and Western blot analysis. The levels of inflammatory cytokines interleukin-6 and tumor necrosis factor-alpha in the lungs were measured by enzyme-linked immunosorbent assay. RESULTS The expression of TLR4 and NF-κBp56 in lungs and of inflammatory cytokines in serum significantly increased in the SAP group compared with the control group(P < 0.05), but was significantly decreased in the ω-3FA group compared with the soybean oil group at 12 and 24 h(P < 0.05).CONCLUSION During the initial stage of SAP, ω-3FA can efficiently lower the inflammatory response and reduce lung injury by triggering the TLR4/NF-κBp56 signal pathway. 展开更多
关键词 Severe acute pancreatitis ω-3 fatty acids Lung injury Toll-like receptor 4 Nuclear factor-κB p56 CYTOKINE
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Cytochrome P450 monooxygenase-mediated eicosanoid pathway:A potential mechanistic linkage between dietary fatty acid consumption and colon cancer risk
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作者 Weicang Wang Jianan Zhang Guodong Zhang 《Food Science and Human Wellness》 SCIE 2019年第4期337-343,共7页
Human consumption of linoleic acid(LA,18:2ω-6,abundant in vegetable oils)is very high.Animal experiments showed that excessive LA intake increased azoxymethane-induced colon tumorigenesis,however,the impact of excess... Human consumption of linoleic acid(LA,18:2ω-6,abundant in vegetable oils)is very high.Animal experiments showed that excessive LA intake increased azoxymethane-induced colon tumorigenesis,however,the impact of excessive LA on colon cancer in human is not conclusive,making it difficult to make dietary recommendations for optimal intake of LA.Understanding the molecular mechanisms of LA on colon tumorigenesis could help to clarify its health effect,and facilitate development of mechanismbased strategies for preventing colon cancer.Recent studies show that the previously unappreciated cytochrome P450 monooxygenase-mediated eicosanoid pathway is upregulated in colon cancer and plays critical roles in its pathogenesis,and could contribute to the effects of dietary LA,as well asω-3 fatty acids,on colon tumorigenesis.In this review,we will discuss recent studies about the roles of cytochrome P450 monooxygenases in fatty acid metabolism and its roles in colonic inflammation and colon cancer,and how this information could help us to clarify the health impacts of dietary fatty acids. 展开更多
关键词 Linoleic acid polyunsaturated fatty acids ω-3 Fatty acids Colon cancer Colonic inflammation Cytochrome p450 EICOSANOIDS
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新型配合物Zn(p-FBA)_2(phen)(H_2O)的合成及其晶体结构
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作者 石智强 季宁宁 李季坤 《合成化学》 CAS CSCD 北大核心 2011年第2期218-221,共4页
以醋酸锌、对氟苯甲酸(p-FBA)和邻菲啰啉(phen)为原料,在33%甲醇中通过水热反应合成了新型的单核锌(Ⅱ)配合物Zn(p-FBA)2(phen)(H2O)(1),其结构经UV-Vis,IR,元素分析,热重分析和X-射线单晶衍射表征。1具有较好的热稳定性。1属于三斜晶系... 以醋酸锌、对氟苯甲酸(p-FBA)和邻菲啰啉(phen)为原料,在33%甲醇中通过水热反应合成了新型的单核锌(Ⅱ)配合物Zn(p-FBA)2(phen)(H2O)(1),其结构经UV-Vis,IR,元素分析,热重分析和X-射线单晶衍射表征。1具有较好的热稳定性。1属于三斜晶系,P-1空间群,晶胞参数a=7.893(7),b=10.412(9),c=14.473(13),α=104.504(15)°,β=97.780(17)°,γ=96.431(15)°,V=1 127.6(17)3,Z=2,Dc=1.596 g.cm-3,R1=0.083 2,wR2=0.179 9。1的晶体是由孤立的分子所组成,五配位的锌(Ⅱ)呈畸变的三角双锥结构。1通过分子间弱的C-H┈O氢键形成了一维链状结构,同时分子内O-H┈O氢键起到了稳定1的作用。 展开更多
关键词 对氟苯甲酸 邻菲啰啉 锌(Ⅱ)配合物 晶体结构 合成
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Uncoupling tumor necrosis factor-αand interleukin-10 at tumor immune microenvironment of breast cancer through miR-17-5p/MALAT-1/H19 circuit
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作者 RAGHDA A.SOLIMAN RANA A.YOUNESS +5 位作者 TAMER M.MANIE EMAD KHALLAF MOHAMED EL-SHAZLY MONA ABDELMOHSEN HEBA HANDOUSSA MOHAMED Z.GAD 《BIOCELL》 SCIE 2022年第3期769-783,共15页
Triple Negative Breast Cancer(TNBC)immunotherapy has recently shown promising approach.However,some TNBC patients presented with resistance.One of the reasons was attributed to the excessive release of cytokines at th... Triple Negative Breast Cancer(TNBC)immunotherapy has recently shown promising approach.However,some TNBC patients presented with resistance.One of the reasons was attributed to the excessive release of cytokines at the tumor microenvironment(TME)such as Tumor necrosis factor alpha(TNF-α)and Interleukin-10(IL-10).Fine regulation of these cytokines’levels via non-coding RNAs(ncRNAs)might alleviate the immune quiescent nature of TME at TNBC tumors.However,the extrapolation of ncRNAs as therapeutic tools is highly challenging.Therefore,disentanglement the nature for the isolation of natural compounds that could modulate the ncRNAs and their respective targets is an applicable translational therapeutic approach.Hence,this study aimed to targeting the chief immune suppressive cytokines at the TME(TNF-αand IL-10)via ncRNAs and to examine the effects of Rosemary aerial parts extract on the expression levels of these ncRNAs in TNBC.Results revealed miR-17-5p as a dual regulator of TNF-αand IL-10.Moreover,an intricate interaction has been shown between miR-17-5p and the oncogenic lncRNAs:MALAT1 and H19.Knocking down of MALAT1 and/or H19 caused an induction in miR-17-5p and reduction in TNF-αand IL-10 expression levels.miR-17-5p was found to be down-regulated,while TNF-α,IL-10,MALAT1 and H19 were up-regulated in BC patients.Forced expression of miR-17-5p in MDA-MB-231 cells reduced TNF-α,IL-10,MALAT1 and H19 expression levels,as well as several BC hallmarks.In a translational approach,ursolic acid(UA)isolated from rosemary induced the expression of miR-17-5p,MALAT1 and decreased H19 expression levels.In conclusion,this study suggests miR-17-5p as a tumor suppressor and an immune-activator miRNA in BC through tuning up the immunological targets TNF-α,IL-10 at the TME and the oncological mediators MALAT1 and H19 lncRNAs. 展开更多
关键词 Breast cancer Tumor microenvironment CYTOKINES TNF-α IL-10 miR-17-5p MALAT1 H19 lncRNAs miRNA Ursolic acid
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有机中间体3'-氯-对氟苯丙酮的合成研究 被引量:1
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作者 王树清 王跃 +1 位作者 王歆然 高崇 《有机氟工业》 CAS 2012年第2期7-9,共3页
在催化剂存在下,以对氟苯甲酸、3'-氯丙酸为原料合成了3'-氯-对氟苯丙酮,并考察了缩合反应温度及反应时间、原料配比和催化剂用量等对反应的影响,最适宜的工艺条件:缩合反应温度为165℃、缩合反应时间7 h;脱羧反应温度为290~29... 在催化剂存在下,以对氟苯甲酸、3'-氯丙酸为原料合成了3'-氯-对氟苯丙酮,并考察了缩合反应温度及反应时间、原料配比和催化剂用量等对反应的影响,最适宜的工艺条件:缩合反应温度为165℃、缩合反应时间7 h;脱羧反应温度为290~295℃、脱羧反应时间0.5~1 h;n(3'-氯丙酸)∶n(对氟苯甲酸)=0.6∶0.1;催化剂的用量为2 g(对氟苯甲酸为0.1mol的情况下)。产物收率79.6%,产品纯度w(3'-氯-对氟苯丙酮)为99.0%。 展开更多
关键词 3’--对氟苯丙酮 对氟苯甲酸 3’-氯丙酸
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光催化-电化学联用测定对氟苯甲酸含量
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作者 谢艳招 林凰 +1 位作者 赵林 何芳 《福建分析测试》 CAS 2013年第3期16-20,共5页
目的:建立一种光催化-电化学联用测定水中对氟苯甲酸含量的新方法。方法:在Pt/TiO2存在下,光催化降解水中少量对氟苯甲酸,采用开路电位-时间曲线法,测定光催化降解对氟苯甲酸2 h时产生的氟离子含量,实验结果显示对氟苯甲酸的初始浓度与... 目的:建立一种光催化-电化学联用测定水中对氟苯甲酸含量的新方法。方法:在Pt/TiO2存在下,光催化降解水中少量对氟苯甲酸,采用开路电位-时间曲线法,测定光催化降解对氟苯甲酸2 h时产生的氟离子含量,实验结果显示对氟苯甲酸的初始浓度与光催化生成氟离子的量成良好线性关系,考察了测定方法的标准工作曲线、精密度和准确度。结果:标准工作曲线的回归方程分别为y=3.3318x+0.0002(R2=0.9997)和y=17.826x-44.634(R2=0.9990),线性范围分别为1.00×10-6~1.00×10-4mol.L-1和1.00×10-4~1.00×10-3mol.L-1。结论:采用光催化-电化学联用技术测定水溶液中少量对氟苯甲酸含量,测定结果准确可靠。 展开更多
关键词 光催化 降解 电化学 测定 对氟苯甲酸
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Gambogic Acid Induces Cell Apoptosis and Inhibits MAPK Pathway in PTEN^(-/-)/p53^(-/-) Prostate Cancer Cells In Vitro and Ex Vivo 被引量:10
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作者 PAN Hong LU Li-yuan +3 位作者 WANG Xue-qian LI Bin-xue Kathleen Kelly LIN Hong-sheng 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2018年第2期109-116,共8页
Objective: To investigate the effect of gambogic acid(GA) on the growth and cell death of castrate resistant prostate cancer(PC) with phosphate and tension homology(PTEN) and p53 genes deleted in vitro and ex v... Objective: To investigate the effect of gambogic acid(GA) on the growth and cell death of castrate resistant prostate cancer(PC) with phosphate and tension homology(PTEN) and p53 genes deleted in vitro and ex vivo, and elucidate the underlying possible molecular mechanisms. Methods: PTEN^(-/-)/p53^(-/-)PC cells and Los Angeles prostate cancer-4(LAPC-4) cells were treated with GA for 24 h and 48 h, then cell viability was determined by cell proliferation assay. PTEN^(-/-)/p53^(-/-)PC cells organoids number was calculated under GA treatment for 1 week. In addition, cell titer glo assay was performed to analyze 3 dimensional cell viability of patients derived xenografts(PDX) 170.2 organoids. Flow cytometry was used to detect apoptotic cells treated with GA. And confocal image was performed to detect the apoptotic mitochondrial morphological changes. Apoptotic cell death related protein levels were measured through Western blot(WB) in GA treated cells and organoids. The expression levels of mitogen-activated protein kinases(MAPKs) pathway related ribonucleic acid(RNAs) and proteins were analyzed by reverse transcription polymerase chain reaction(RT-PCR) and WB, respectively. Results: The treatment of GA significantly reduced cell viability of PTEN^(-/-)/p53^(-/-)PC cells and LAPC-4 in a time-and concentration-dependent manner. In organoids, GA showed strong inhibition towards organoids' numbers and diameters and continuously led to a complete organoids inhibition with GA 150 nmol/L. Ex vivo results validated that GA 1 μmol/L inhibited 44.6% PDX170.2 organoids growth. As for mechanism, flow cytometry detected continuously increased apoptotic portion under GA treatment from 1.98% to 11.78%(6 h) and 29.94%(8 h, P〈0.05). In addition, mitochondrial fragmentation emerged in GA treated cells indicated the mitochondrial apoptotic pathway might be involved. Furthermore, WB detected caspases-3,-9 activation and light chain(LC)-3 conversion with GA treatment. WB revealed decreased activity of MAPK pathway and down-regulation of downstream c-fos oncogene RNA level was detected by RT-PCR before undergoing apoptosis(P〈0.05). Conclusion: GA was a potent anti-tumor compound as for PTEN-/-/p53-/-PC, which contributed to cell apoptosis via inhibition of the MAPK pathway and c-fos. 展开更多
关键词 gambogic acid prostate cancer apoptosis mitogen-activated protein kinase pTEN-/-/p53-/-
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对氟甲苯液相氧化制备对氟苯甲醛 被引量:4
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作者 方永勤 王兆岗 吕新宇 《常州大学学报(自然科学版)》 CAS 2011年第2期32-35,共4页
以对氟甲苯为原料,Co/Mn/Br为催化体系,氧气为氧化剂,常压下液相氧化制备对氟苯甲醛,探讨了催化剂配比、催化剂用量、反应温度、溶剂用量、氧气流量对氧化反应的影响。较优工艺条件为:90℃,氧气12.5mL/min,n(Co)∶n(Mn)∶n(Br)=1∶2∶1... 以对氟甲苯为原料,Co/Mn/Br为催化体系,氧气为氧化剂,常压下液相氧化制备对氟苯甲醛,探讨了催化剂配比、催化剂用量、反应温度、溶剂用量、氧气流量对氧化反应的影响。较优工艺条件为:90℃,氧气12.5mL/min,n(Co)∶n(Mn)∶n(Br)=1∶2∶1.5,催化剂用量2.0%(以对氟甲苯计),m(乙酸)∶m(对氟甲苯)=4∶1,反应8h,对氟甲苯转化率35.3%,对氟苯甲醛选择性57.4%。 展开更多
关键词 对氟甲苯 对氟苯甲醛 对氟苯甲酸 液相氧化
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医药中间体对氟苯丁酮的合成研究
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作者 王树清 高崇 +1 位作者 刘政 陈智萍 《化学世界》 CAS CSCD 北大核心 2012年第2期98-100,共3页
在催化剂存在下,以对氟苯甲酸、丁酸为原料合成对氟苯丁酮,分别研究了缩合反应温度及反应时间、脱羧反应温度及反应时间、原料配比和催化剂用量等条件对合成对氟苯丁酮反应的影响,确定了最适宜的操作条件。该方法合成对氟苯丁酮的最佳... 在催化剂存在下,以对氟苯甲酸、丁酸为原料合成对氟苯丁酮,分别研究了缩合反应温度及反应时间、脱羧反应温度及反应时间、原料配比和催化剂用量等条件对合成对氟苯丁酮反应的影响,确定了最适宜的操作条件。该方法合成对氟苯丁酮的最佳操作条件是:缩合反应温度为165℃、缩合反应时间8.5h;脱羧反应温度为280~285℃、脱羧反应时间2.5h;n(丁酸):n(对氟苯甲酸)=0.7:0.1;催化剂还原铁粉的用量为2.5g(对氟苯甲酸为0.1mol的情况下)。对氟苯丁酮的收率可达到88.53%以上,产品纯度99.0%。 展开更多
关键词 对氟苯丁酮 对氟苯甲酸 丁酸
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相转移催化法由对硝基苯甲酸合成对氟苯甲酸的探讨
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作者 徐建泓 方苗利 《浙江医学教育》 2004年第1期53-55,共3页
为了简化对氟苄胺的合成,降低成本,用季铵盐作为相转移催化剂以促进对硝基苯甲酸到对氟苯甲酸的转变,研究了反应时间、温度和催化剂用量对对氟苯甲酸产率的影响,对氟苯甲酸的产率达到了78.9%,比文献报道的75.5%的产率高,同时使反应时间... 为了简化对氟苄胺的合成,降低成本,用季铵盐作为相转移催化剂以促进对硝基苯甲酸到对氟苯甲酸的转变,研究了反应时间、温度和催化剂用量对对氟苯甲酸产率的影响,对氟苯甲酸的产率达到了78.9%,比文献报道的75.5%的产率高,同时使反应时间从10小时缩短为5小时。还考察了其他相转移催化剂的影响。 展开更多
关键词 对氟苄胺 对硝基苯甲酸 对氟苯甲酸 十六烷基三甲基溴化铵 合成
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miR-7/TGF-β2 axis sustains acidic tumor microenvironment-induced lung cancer metastasis 被引量:3
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作者 Tao Su Suchao Huang +15 位作者 Yanmin Zhang Yajuan Guo Shuwei Zhang Jiaji Guan Mingjing Meng Linxin Liu Caiyan Wang Dihua Yu Hiu-Yee Kwan Zhiying Huang Qiuju Huang Elaine Lai-Han Leung Ming Hu Ying Wang Zhongqiu Liu Linlin Lu 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2022年第2期821-837,共17页
Acidosis,regardless of hypoxia involvement,is recognized as a chronic and harsh tumor microenvironment(TME)that educates malignant cells to thrive and metastasize.Although overwhelming evidence supports an acidic envi... Acidosis,regardless of hypoxia involvement,is recognized as a chronic and harsh tumor microenvironment(TME)that educates malignant cells to thrive and metastasize.Although overwhelming evidence supports an acidic environment as a driver or ubiquitous hallmark of cancer progression,the unrevealed core mechanisms underlying the direct effect of acidification on tumorigenesis have hindered the discovery of novel therapeutic targets and clinical therapy.Here,chemical-induced and transgenic mouse models for colon,liver and lung cancer were established,respectively.miR-7 and TGF-β2 expressions were examined in clinical tissues(n=184).RNA-seq,miRNA-seq,proteomics,biosynthesis analyses and functional studies were performed to validate the mechanisms involved in the acidic TME-induced lung cancer metastasis.Our data show that lung cancer is sensitive to the increased acidification of TME,and acidic TME-induced lung cancer metastasis via inhibition of miR-7-5 p.TGF-β2 is a direct target of miR-7-5 p.The reduced expression of miR-7-5 p subsequently increases the expression of TGF-β2 which enhances the metastatic potential of the lung cancer.Indeed,overexpression of miR-7-5 p reduces the acidic p H-enhanced lung cancer metastasis.Furthermore,the human lung tumor samples also show a reduced miR-7-5 p expression but an elevated level of activated TGF-β2;the expressions of both miR-7-5 p and TGF-β2 are correlated with patients’survival.We are the first to identify the role of the miR-7/TGF-β2 axis in acidic p H-enhanced lung cancer metastasis.Our study not only delineates how acidification directly affects tumorigenesis,but also suggests miR-7 is a novel reliable biomarker for acidic TME and a novel therapeutic target for non-small cell lung cancer(NSCLC)treatment.Our study opens an avenue to explore the p H-sensitive subcellular components as novel therapeutic targets for cancer treatment. 展开更多
关键词 acidic tumor microenvironment miR-7-5p TGF-Β2 METASTASIS Lung cancer pH INVASION
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在Pt/TiO_2上光催化降解污水中的对氟苯甲酸 被引量:11
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作者 谢艳招 吴松辉 +2 位作者 赵林 蔡聪育 肖华山 《分子催化》 EI CAS CSCD 北大核心 2012年第5期449-455,共7页
在Pt/TiO2存在下,研究了光催化降解对氟苯甲酸的反应.考察了反应时间、溶液初始pH值以及污染物初始浓度对光催化反应的影响.结果表明,溶液的紫外吸光度值随反应时间不断下降;反应7 h时,溶液的TOC去除率达23.2%;反应0.5~2 h内,氟离子平... 在Pt/TiO2存在下,研究了光催化降解对氟苯甲酸的反应.考察了反应时间、溶液初始pH值以及污染物初始浓度对光催化反应的影响.结果表明,溶液的紫外吸光度值随反应时间不断下降;反应7 h时,溶液的TOC去除率达23.2%;反应0.5~2 h内,氟离子平均生成速率为3.53×10-5mol.L-1.h-1;在反应3~7 h内,氟离子平均生成速率为6.22×10-5mol.L-1.h-1.在溶液初始pH值=3.34~3.72时,氟离子生成速率最大,在碱性范围内,氟离子的生成速率为零.当C0(p-fluorobenzoic acid)<1.80×10-3mol.L-1时,光催化降解生成氟离子的速率随着对氟苯甲酸浓度的增大而增大;当C0(p-fluorobenzoic acid)>2.00×10-3mol.L-1时,光催化降解生成氟离子的速率不再随污染物浓度的变化而发生变化.探讨了可能的反应机理. 展开更多
关键词 光催化 降解 对氟苯甲酸 反应机理
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