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Antibacterial mechanism of kojic acid and tea polyphenols against Escherichia coli O157:H7 through transcriptomic analysis 被引量:1
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作者 Yilin Lin Ruifei Wang +4 位作者 Xiaoqing Li Keren Agyekumwaa Addo Meimei Fang Yehui Zhang Yigang Yu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期736-747,共12页
Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity ag... Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity against E.coli O157:H7 than using either alone.This study aimed to explore responses underlying the antibacterial mechanisms of kojic acid and tea polyphenols from the gene level.The functional enrichment analysis by comparing kojic acid and tea polyphenols individually or synergistically against E.coli O157:H7 found that acid resistance systems in kojic acid were activated,and the cell membrane and genomic DNA were destructed in the cells,resulting in“oxygen starvation”.The oxidative stress response triggered by tea polyphenols inhibited both sulfur uptake and the synthesis of ATP,which affected the bacteria's life metabolic process.Interestingly,we found that kojic acid combined with tea polyphenols hindered the uptake of iron that played an essential role in the synthesis of DNA,respiration,tricarboxylic acid cycle.The results suggested that the iron uptake pathways may represent a novel approach for kojic acid and tea polyphenols synergistically against E.coli O157:H7 and provided a theoretical basis for bacterial pathogen control in the food industry. 展开更多
关键词 Kojic acid Tea polyphenols Antibacterial mechanism Escherichia coli O157:H7 RNA-SEQ
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Unraveling the therapeutic mechanisms of myristic acid and luteolin 7-rutinoside in oral cancer: insights from network pharmacology and molecular docking analysis
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作者 Ansari Vikhar Danish Ahmad Misba Ruhi +4 位作者 Syed Ayaz Ali Qazi Yasar Mohd.Mukhtar Khan Subur W Khan Mohammed Imran Anees 《Pharmacology Discovery》 2024年第2期1-9,共9页
Background:The compound Luteolin-7-rutinoside(L7R)is a flavone derivative of luteolin,predominantly identified in plant species belonging to the families Asteraceae.Conversely,Myristic acid is characterized by its str... Background:The compound Luteolin-7-rutinoside(L7R)is a flavone derivative of luteolin,predominantly identified in plant species belonging to the families Asteraceae.Conversely,Myristic acid is characterized by its structure as a 14-carbon,unsaturated fatty acid.In this investigation,we endeavor to elucidate the putative mechanisms underlying the therapeutic effects of Myristic Acid and Luteolin 7-rutinoside in the context of oral cancer treatment,employing network pharmacology coupled with molecular docking methodologies.Methods:The protein targets of Myristic Acid and Luteolin 7-rutinoside were identified through a search on the Swiss Target Database.Subsequently,a compound-target network was constructed using Cytoscape 3.9.1.Targets associated with OC were retrieved from the OMIM and GeneCards databases.The overlap between compound targets and OC-related targets was determined,and the resulting shared targets were subjected to protein-protein interaction(PPI)network analysis using the STRING database.Additionally,gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses were conducted on the identified targets.Molecular docking were performed to investigate the interactions between the core target and the active compound.Results:The component target network comprises 103 nodes and 102 edges.Among the proteins in the protein-protein interaction(PPI)network,those with higher degrees are TNF,PPARG,and TP53.Analysis through Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways indicates that the treatment of OC with Myristic Acid and Luteolin 7-rutinoside primarily involves the regulation of miRNA transcription and inflammatory response.The identified signaling pathways include Pathways in cancer,PPAR signaling pathway,EGFR signaling pathway,and TNF signaling pathway.Molecular docking studies reveal that Luteolin 7-rutinoside and Myristic acid exhibit higher affinity towards TNF,PPARG,TP53,and EGFR.Conclusion:This study reveals the potential molecular mechanism of Myristic Acid and Luteolin 7-rutinoside in the treatment of oral cancer,and provides a reference for subsequent basic research. 展开更多
关键词 myristic acid luteolin 7-rutinoside network pharmacology oral cancer molecular docking
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改性磁性生物质炭对酸性橙7的吸附
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作者 刘传福 张晨 +4 位作者 吴正德 张健 於中烨 陈宏彬 邱祖民 《南昌大学学报(理科版)》 CAS 2024年第1期42-51,共10页
以竹粉水热炭(BC)作为基底,负载Fe 3O 4磁性材料使其具有磁性,同时经共沉淀法在磁性水热炭表面生长层状双氢氧化物(LDH)来提升吸附性能。将制备的材料用于吸附酸性橙7,探究了不同pH、离子浓度、水质、微塑料、腐殖酸等因素的影响,并通过... 以竹粉水热炭(BC)作为基底,负载Fe 3O 4磁性材料使其具有磁性,同时经共沉淀法在磁性水热炭表面生长层状双氢氧化物(LDH)来提升吸附性能。将制备的材料用于吸附酸性橙7,探究了不同pH、离子浓度、水质、微塑料、腐殖酸等因素的影响,并通过SEM、BET、XRD、FT-IR、VSM等表征手段,分析了吸附过程的机理。结果表明:吸附符合Langmuir模型和准二阶动力学模型。在40℃下,平衡吸附量能达到271.64 mg·g^(-1),该吸附剂具有较好的循环吸附效果,循环4次仍具有较好的去除率。 展开更多
关键词 吸附 水热炭 层状双氢氧化物(LDH) 酸性橙7
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基于二价钴催化氧化脱色酸性橙7的分光光度法快速测定水中过氧乙酸浓度
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作者 许冬梅 陈思颖 +5 位作者 董冬吟 杨仕毅 陈铃心 林晓峰 崔航宇 邹景 《环境化学》 CAS CSCD 北大核心 2024年第9期3165-3173,共9页
文章开发建立了一种快速、简便、准确测定水中过氧乙酸浓度的分光光度方法.该方法基于催化氧化脱色原理,利用Co(Ⅱ)选择性催化过氧乙酸氧化脱色酸性橙7.研究结果表明,酸性橙7脱色程度随过氧乙酸浓度的提高而增加,且酸性橙7在其特征吸收... 文章开发建立了一种快速、简便、准确测定水中过氧乙酸浓度的分光光度方法.该方法基于催化氧化脱色原理,利用Co(Ⅱ)选择性催化过氧乙酸氧化脱色酸性橙7.研究结果表明,酸性橙7脱色程度随过氧乙酸浓度的提高而增加,且酸性橙7在其特征吸收波长484 nm处的吸光度变化值与过氧乙酸浓度具有良好的线性关系.该方法的检测时间仅为1 min、最低检测限为0.48μmol·L^(-1)且线性范围为0—60μmol·L^(-1).共存的过氧化氢以及实际水体水质背景中存在的硫酸根离子、氯离子、碳酸氢根离子、硝酸根离子、腐殖酸和三价铁离子对该方法的测定结果均没有显著影响.该方法还成功运用于监测过氧乙酸活化体系降解双氯芬酸过程中过氧乙酸的浓度变化. 展开更多
关键词 过氧乙酸 测定方法 过氧化氢 酸性橙7 二价钴
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香豆酸诱导MCF-7细胞凋亡的代谢与氧化应激影响
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作者 段芳芳 李红 《江西医药》 CAS 2024年第4期335-339,353,共6页
目的 探讨香豆酸诱导乳腺癌细胞MCF-7凋亡的机制及氧化应激与代谢的影响。方法 采用氧化相关蛋白活性研究香豆酸对MCF-7氧化应激的影响;液相质谱仪结合代谢组学探索香豆酸对MCF-7细胞代谢的影响。结果 香豆酸呈浓度依赖式对MCF-7细胞凋... 目的 探讨香豆酸诱导乳腺癌细胞MCF-7凋亡的机制及氧化应激与代谢的影响。方法 采用氧化相关蛋白活性研究香豆酸对MCF-7氧化应激的影响;液相质谱仪结合代谢组学探索香豆酸对MCF-7细胞代谢的影响。结果 香豆酸呈浓度依赖式对MCF-7细胞凋亡具有一定的促进作用,并上调细胞的氧化应激性导致MCF-7细胞氧化系统失衡;同时香豆酸影响MCF-7的细胞代谢,主要是体现糖代谢,富集显著通路集糖酵解;并筛选到差异代谢物563个,其中上调463个,下调100个。结论 香豆酸诱导MCF-7细胞凋亡作用机制可能是通过影响细胞的氧化应激性以及调控细胞糖代谢来实现。 展开更多
关键词 香豆酸 乳腺癌 MCF-7 氧化应激 细胞代谢 糖酵解
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7-羟乙基白杨素聚乳酸-羟基乙酸共聚物纳米粒的制备及体外释放评价 被引量:1
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作者 王小娟 杨宝乐 +4 位作者 马川 何蕾 景临林 黄琼 马慧萍 《浙江大学学报(医学版)》 CAS CSCD 北大核心 2024年第1期116-125,共10页
目的:制备和评价7-羟乙基白杨素(7-HEC)聚乳酸-羟基乙酸共聚物(PLGA)纳米粒。方法:采用乳化溶剂挥发法制备7-HEC/PLGA纳米粒,以粒径、多分散系数(PDI)、包封率、载药量及Zeta电位为评价指标,通过单因素考察结合Box-Behnken响应面法优化... 目的:制备和评价7-羟乙基白杨素(7-HEC)聚乳酸-羟基乙酸共聚物(PLGA)纳米粒。方法:采用乳化溶剂挥发法制备7-HEC/PLGA纳米粒,以粒径、多分散系数(PDI)、包封率、载药量及Zeta电位为评价指标,通过单因素考察结合Box-Behnken响应面法优化处方。采用甘露醇作为冻干保护剂制备冻干粉,对最优处方制备的7-HEC/PLGA纳米粒进行表征及体外释放研究。结果:经Box-Behnken响应面法优化后的最优处方为:药载比2.12∶20,油水体积比1∶14.7,乳化剂为2.72%大豆磷脂。最优处方条件制备的7-HEC/PLGA纳米粒的平均粒径为(240.28±0.96)nm、PDI为0.25±0.69、包封率为(75.74±0.80)%、载药量为(6.98±0.83)%、电位为(-18.17±0.17)mV。体外释放48 h内累积释放度达到50%以上。结论:优化所得处方工艺稳定、操作简便。所得7-HEC/PLGA纳米粒粒度均匀,包封率较高。相对于7-HEC原料药,7-HEC/PLGA纳米粒的溶出度显著提高。 展开更多
关键词 7-羟乙基白杨素 聚乳酸-羟基乙酸共聚物纳米粒 乳化溶剂挥发法 处方优化 体外释放
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羟基积雪草酸对乳腺癌MCF-7细胞增殖、凋亡和自噬的影响
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作者 谢珠珠 杨柯鸿 +3 位作者 冯文静 邹攀 钱荣康 钱荣华 《湖南中医药大学学报》 CAS 2024年第5期771-777,共7页
目的探讨羟基积雪草酸(madecassic acid,MA)对乳腺癌MCF-7细胞增殖、凋亡及自噬的影响。方法将MCF-7细胞分为阴性对照组、不同浓度的MA(80、100、120、140、160μmol/L)组、不同浓度的他莫昔芬(10、20、30、40、50、35μmol/L)组,干预24... 目的探讨羟基积雪草酸(madecassic acid,MA)对乳腺癌MCF-7细胞增殖、凋亡及自噬的影响。方法将MCF-7细胞分为阴性对照组、不同浓度的MA(80、100、120、140、160μmol/L)组、不同浓度的他莫昔芬(10、20、30、40、50、35μmol/L)组,干预24、36、48 h。初步确定MA发挥抗乳腺癌作用的最佳浓度和最佳时间后,采用MTT法检测细胞活力,计算相应的半抑制浓度(half maximal inhibitory concentration,IC50)值;流式细胞术检测细胞凋亡;JC-1荧光探针检测线粒体膜电位变化;Western blot法检测细胞增殖蛋白细胞核抗原蛋白(proliferating cell nuclear antigen,PCNA)、自噬蛋白苄氯素-1(Beclin-1)、微管相关蛋白1轻链3-Ⅱ/Ⅰ(microtubule-associated protein1 light chain 3Ⅱ/Ι,LC3Ⅱ/Ι)、螯合体1(protein 62,p62)的蛋白相对表达水平。透射电镜检测自噬小体。结果发挥抗肿瘤作用的他莫昔芬最佳浓度为35μmol/L,MA最佳浓度为140μmol/L,最佳时间均为48 h。与阴性对照组相比,MA140μmol/L组和他莫昔芬35μmol/L组的细胞凋亡率,细胞荧光相对强度以及LC3Ⅱ/Ⅰ、Beclin-1蛋白相对表达水平均升高(P<0.05,P<0.01);PCNA、P62蛋白相对表达水平降低(P<0.05,P<0.01)。与MA 140μmol/L组相比,他莫昔芬35μmol/L组细胞凋亡率、细胞荧光相对强度以及Beclin-1蛋白相对表达水平明显升高(P<0.01),PCNA蛋白相对表达水平明显降低(P<0.01)。阴性对照组MCF-7细胞膜完整,核膜清晰,细胞形态良好;MA 140μmol/L组细胞膜、细胞核形态不规则,线粒体基质密度较高、嵴扩张,可见自噬小体;他莫昔芬35μmol/L组细胞膜局部溶解、破损,可见双核仁,线粒体肿胀、基质溶解,可见自噬小体。结论MA可抑制乳腺癌MCF-7细胞的增殖、诱导细胞凋亡和自噬。 展开更多
关键词 乳腺癌 羟基积雪草酸 增殖 凋亡 自噬 MCF-7细胞
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茯苓酸通过调节Nrf2/SLC7A11/GPX4信号通路抑制氧糖剥夺/复氧诱导的心肌细胞铁死亡 被引量:1
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作者 王飞飞 陈伯艳 李琼 《中西医结合心脑血管病杂志》 2024年第2期267-273,共7页
目的:探究茯苓酸通过调节核因子E2相关因子2(Nrf2)/溶质载体家族7成员11(SLC7A11)/谷胱甘肽过氧化物酶4(GPX4)信号通路抑制氧糖剥夺/复氧(OGD/R)诱导的心肌细胞铁死亡的机制。方法:体外培养大鼠心肌细胞H9c2,诱导建立细胞OGD/R模型后以0... 目的:探究茯苓酸通过调节核因子E2相关因子2(Nrf2)/溶质载体家族7成员11(SLC7A11)/谷胱甘肽过氧化物酶4(GPX4)信号通路抑制氧糖剥夺/复氧(OGD/R)诱导的心肌细胞铁死亡的机制。方法:体外培养大鼠心肌细胞H9c2,诱导建立细胞OGD/R模型后以0、1.0、2.5、5.0、10.0、20.0μmol/L茯苓酸处理24 h,通过细胞计数试剂盒-8(CCK-8)法检测各处理组细胞活力后筛选出合适的茯苓酸作用浓度。将H9c2细胞随机分为对照组、模型组、茯苓酸组、ML385组(Nrf2抑制剂组)、茯苓酸+ML385组,除对照组外其余各组建立细胞OGD/R模型后以茯苓酸、ML385分组处理,采用CCK-8法与流式细胞实验分别检测各组H9c2细胞活力、凋亡率;采用试剂盒检测各组H9c2细胞培养基上清中乳酸脱氢酶(LDH)、促炎因子[前列腺素E2(PGE2)、肿瘤坏死因子-α(TNF-α)]、抗炎因子白细胞介素(IL)-10水平及细胞抗氧化因子[过氧化氢酶(CAT)、谷胱甘肽(GSH)]、铁死亡相关指标[铁含量、丙二醛(MDA)]水平;采用免疫印迹实验检测各组H9c2细胞凋亡及Nrf2/SLC7A11/GPX4信号通路相关蛋白表达。结果:与对照组比较,模型组细胞凋亡率、LDH释放量、细胞培养基上清中PGE2及TNF-α水平、细胞铁含量、MDA水平及Bax、Caspase-3蛋白表达均升高(P<0.05),细胞活力、细胞培养基上清中IL-10水平、细胞CAT及GSH水平、Bcl-2及Nrf2、SLC7A11、GPX4蛋白表达降低(P<0.05)。与模型组比较,茯苓酸组细胞凋亡率、LDH释放量、细胞培养基上清中PGE2及TNF-α水平、细胞铁含量、MDA水平及Bax、Caspase-3蛋白表达均降低(P<0.05),细胞活力、细胞培养基上清中IL-10水平、细胞CAT及GSH水平、Bcl-2及Nrf2、SLC7A11、GPX4蛋白表达升高(P<0.05);ML385组细胞凋亡率、LDH释放量、细胞培养基上清中PGE2及TNF-α水平、细胞铁含量、MDA水平及Bax、Caspase-3蛋白表达均升高(P<0.05),细胞活力、细胞培养基上清中IL-10水平、细胞CAT及GSH水平、Bcl-2及Nrf2、SLC7A11、GPX4蛋白表达降低(P<0.05)。与茯苓酸组比较,茯苓酸+ML385组细胞凋亡率、LDH释放量、细胞培养基上清中PGE2及TNF-α水平、细胞铁含量、MDA水平及Bax、Caspase-3蛋白表达均升高(P<0.05),细胞活力、细胞培养基上清中IL-10水平、细胞CAT及GSH水平、Bcl-2及Nrf2、SLC7A11、GPX4蛋白表达降低(P<0.05)。结论:茯苓酸可通过激活Nrf2/SLC7A11/GPX4信号而抑制OGD/R诱导的心肌细胞炎症、脂质过氧化与铁死亡,增强其抗氧化活性及细胞活力,最终减轻其细胞凋亡损伤。 展开更多
关键词 氧糖剥夺/复氧 心肌细胞 茯苓酸 核因子E2相关因子2/溶质载体家族7成员11/谷胱甘肽过氧化物酶4 铁死亡 实验研究
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早产儿BPD的危险因素及血浆BMP-7 miR-15b 25-(OH)D_(3)对其诊断价值分析
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作者 马萌萌 赵学辉 杨洁 《安徽医学》 2024年第2期158-162,共5页
目的 探讨早产儿支气管肺发育不良(BPD)的危险因素及血浆骨形成蛋白-7(BMP-7)、微小核糖核酸-15b(miR-15b)、25羟基维生素D_(3)[25-(OH)D_(3)]对其诊断价值。方法 回顾性分析2022年1月至2023年3月河北省沧州中西医结合医院收治的136例... 目的 探讨早产儿支气管肺发育不良(BPD)的危险因素及血浆骨形成蛋白-7(BMP-7)、微小核糖核酸-15b(miR-15b)、25羟基维生素D_(3)[25-(OH)D_(3)]对其诊断价值。方法 回顾性分析2022年1月至2023年3月河北省沧州中西医结合医院收治的136例早产儿的临床资料,根据其是否伴有BPD,将其分为BPD组(n=45)和非BPD组(n=91)。分析早产儿BPD的单因素,采用多因素logistic回归分析早产儿BPD的危险因素,绘制受试者工作特征(ROC)曲线分析血浆BMP-7、miR-15b、25-(OH)D_(3)对早产儿BPD的诊断价值。结果 两组患儿机械通气时间、吸氧时间、有无脓毒血症及血浆BMP-7、miR-15b、25-(OH)D_(3)水平比较,差异有统计学意义(P<0.05)。多因素logistic回归分析结果显示,机械通气时间长、血浆BMP-7、miR-15b水平偏高、血浆25-(OH)D_(3)水平偏低是早产儿BPD的独立危险因素(OR=2.625、2.208、2.280、2.517,P<0.05)。血浆BMP-7、miR-15b、25-(OH)D_(3)联合诊断早产儿BPD的曲线下面积为0.947,高于血浆BMP-7、miR-15b、25-(OH)D_(3)单独检测(0.822、0.849、0.824,P<0.05)。结论 早产儿BPD的危险因素与机械通气时间长、血浆BMP-7、miR-15b水平偏高、血浆25-(OH)D_(3)水平偏低有关,且血浆BMP-7、miR-15b、25-(OH)D_(3)联合检测对早产儿BPD的诊断价值更高。 展开更多
关键词 早产儿 支气管肺发育不良 骨形成蛋白-7 微小核糖核酸-15b 25羟基维生素D3
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癫痫患者脑电图异常和血清BDNF GFAP miR-7-5p表达特征及与认知功能的关系
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作者 白杨 杨越 齐会珍 《河北医学》 CAS 2024年第4期623-629,共7页
目的:探究癫痫患者脑电图异常和BDNF、GFAP、miR-7-5p表达特征,并探究各指标与患者认知功能的关系。方法:本研究以我院2017年4月至2021年4月期间治疗的294例癫痫患者为对象,采用MoCA评分对患者的认知功能进行评价,并据此对患者进行分组... 目的:探究癫痫患者脑电图异常和BDNF、GFAP、miR-7-5p表达特征,并探究各指标与患者认知功能的关系。方法:本研究以我院2017年4月至2021年4月期间治疗的294例癫痫患者为对象,采用MoCA评分对患者的认知功能进行评价,并据此对患者进行分组:将得分≥26分的198例患者纳入认知正常组,得分<26分的96例患者纳入认知障碍组,患者均接受脑电图检查、血清BDNF、GFAP、miR-7-5p检测,比较组间脑电图检查异常情况及血清BDNF、GFAP、miR-7-5p表达差异,并探究上述指标与认知障碍的关联。结果:对两组患者的MoCA评分进行分析可知认知障碍组患者的Mo-CA各项评分均低于认知正常组(P<0.05)。与认知正常组患者相比,认知障碍组患者脑电图无异常占比降低,认知障碍组患者脑电图痫样放电、脑电图慢波发放的发生率高于认知正常组(P<0.05)。与认知正常组患者相比较,认知障碍组BDNF、miR-7-5p降低,GFAP升高(P<0.05)。通过Pearson相关性分析发现,患者的MoCA评分与血清中的BDNF和miR-7-5p表达呈正相关,与其GFAP表达呈负相关(P<0.05)。经ROC曲线分析,血清BDNF、miR-7-5p及GFAP表达对癫痫患者认知障碍的发生具有一定诊断价值,其AUC值分别为0.836、0.845、0.957。结论:伴有认知障碍的癫痫患者脑电图异常特征以脑电图痫样放电、脑电图慢波发放为主,血清BDNF、miR-7-5p表达低于认知正常的癫痫患者,GFAP表达高于认知正常的癫痫患者,且血清BDNF、miR-7-5p及GFAP表达对癫痫患者认知障碍的发生具有一定诊断价值。 展开更多
关键词 癫痫 脑电图异常 认知障碍 脑源性神经营养因子 胶质纤维酸性蛋白 miR-7-5p
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影响光催化超滤膜反应器降解Acid Blue 7的因素研究 被引量:8
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作者 傅剑锋 季民 金洛楠 《化工进展》 EI CAS CSCD 北大核心 2005年第8期916-920,924,共6页
设计研制了一种光催化超滤膜反应器,并选用一种颗粒状纳米级TiO2作光催化剂,对染料AcidBlue7光氧化降解进行了研究。影响染料降解的因素包括:错流速度、催化剂浓度、染料初始浓度、溶液的pH值以及曝气条件。研究结果发现,光催化超滤反... 设计研制了一种光催化超滤膜反应器,并选用一种颗粒状纳米级TiO2作光催化剂,对染料AcidBlue7光氧化降解进行了研究。影响染料降解的因素包括:错流速度、催化剂浓度、染料初始浓度、溶液的pH值以及曝气条件。研究结果发现,光催化超滤反应器对染料废水处理具有较高的处理效果,且颗粒状光催化剂能够实现良好分离。 展开更多
关键词 光催化 颗粒状纳米TiO2 acid BLUE 7 超滤 反应器
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ADSORPTION STUDIES OF TANNIC ACID BY COMMERCIAL ESTER RESIN XAD-7 被引量:4
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作者 李爱民 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第2期231-239,共9页
Tannic acid and its related compounds are known as refractory organic pollutants, and it can create serious problems for the environment. The adsorption and desorption studies of tannic acid on commercial resins XAD-7... Tannic acid and its related compounds are known as refractory organic pollutants, and it can create serious problems for the environment. The adsorption and desorption studies of tannic acid on commercial resins XAD-7 and D-201 are performed, and all data indicates resin XAD-7 can be used as an effective adsorbent for removing tannic acid during water/wastewater treatment. Furthermore, adsorption thermodynamics studies indicate different adsorption mechanisms for TA on XAD-7 and D-201. FT-IR and solid state 13C-NMR spectroscopy are used to explain the adsorption force between XAD-7 and TA. It suggests that hydrogen bonding is the main adsorption force for TA. Finally, XAD-7's adsorption capacity in the presence of different metal ions is investigated, which indicates that heavy metal ions in solutions can decrease the adsorption capacity for TA on ester resin XAD-7. 展开更多
关键词 ADSORPTION Tannic acid RESIN XAD-7 Metal ion.
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RETINOIC ACID DOWN-REGULATES BONE MORPHOGENETIC PROTEIN 7 EXPRESSION IN RAT WITH CLEFT PALATE 被引量:5
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作者 Lei Guo Yu-yan Zhao +2 位作者 Shi-liang Zhang Kui Liu Xiao-yu Gao 《Chinese Medical Sciences Journal》 CAS CSCD 2008年第1期28-31,共4页
Objective To evaluate the effects of retinoic acid (RA) on expression of bone morphogenetic protein 7 ( BMP-7 ) in rat fetus with cleft palate, and the effects of RA on proliferation and apoptosis of osteoblasts. ... Objective To evaluate the effects of retinoic acid (RA) on expression of bone morphogenetic protein 7 ( BMP-7 ) in rat fetus with cleft palate, and the effects of RA on proliferation and apoptosis of osteoblasts. Methods All-trans RA (ATRA) was used to induce congenital cleft palate in Wistar rat. BMP-7 mRNA expression in maxillary bone tissue of fetal rats was measured by Northern blotting analysis. Flow cytometry and MTF assay were used to measure the apoptosis and proliferation of ATRA-treated MC-3T3-E1 cells. BMP-7 mRNA and protein expressions in ATRA-treated MC-3T3-E1 cells were detected by RT-PCR and Western blotting analysis. Remilts ATRA could induce cleft palate of rat fetus. The incidence rate of cleft palate induced by 100 mg/kg AT-RA (45.5%) was significantly higher than 50 mg/kg ATRA ( 12.5%, P 〈 0. 05 ). BMP-7 mRNA expression decreased in maxillary bone tissue of rat fetus with cleft palate. MC-3T3-E1 cells proliferation treated with 1 × 10^-6 mol/L ATRA decreased by 60%, the cell apoptosis increased by 2 times. BMP-7 mRNA and protein levels in MC-3T3-E1 cells treated with 1 × 10^-6 mol/L ATRA decreased by 60% and 80%, respectively, compared with ATRA-untreated cells ( P 〈 0.05 ). Conclusions BMP-7 may play an important role in embryonic palate development. RA may possess the ability to down-regulate cell proliferation through regulation of BMP-7 gene expression. 展开更多
关键词 bone morphogenetic protein 7 retinoic acid cleft palate OSTEOBLAST
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Regeneration of Acid Orange 7 Exhausted Granular Activated Carbon Using Pulsed Discharge Plasmas 被引量:1
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作者 王慧娟 郭贺 +1 位作者 刘永杰 依成武 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第10期881-886,共6页
In this paper, a pulsed discharge plasma (PDP) system with a multi-needle-to-plate electrodes geometry was set up to investigate the regeneration of acid orange 7 (AO7) exhausted granular activated carbon (GAC).... In this paper, a pulsed discharge plasma (PDP) system with a multi-needle-to-plate electrodes geometry was set up to investigate the regeneration of acid orange 7 (AO7) exhausted granular activated carbon (GAC). Regeneration of GAC was studied under different conditions of peak pulse discharge voltage and water pH, as well as the modification effect of GAC by the pulse discharge process, to figure out the regeneration efficiency and the change of the GAC structure by the PDP treatment. The obtained results showed that there was an appropriate peak pulse voltage and an optimal initial pH value of the solution for GAC regeneration. Analyses of scanning electron microscope (SEM), Boehm titration, Brunauer-Emmett-Teller (BET), Horvath-Kawazoe (HK), and X-ray Diffraction (XRD) showed that there were more mesopore and macropore in the regenerated GAC and the structure turned smoother with the increase of discharge voltage; the amount of acidic functional groups on the GAC surface increased while the amount of basic functional groups decreased after the regeneration process. From the result of the XRD analysis, there were no new substances produced on the GAC after PDP treatment. 展开更多
关键词 pulsed discharge plasma acid orange 7 granular activated carbon REGENERATION pore structure functional groups
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Synthesis and Crystal Structure of 7-Nitro-5-sulfo-napthalene-1,4-dicarboxylate Acid 被引量:1
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作者 WU Rui-Feng ZHANG Tong-Lai +3 位作者 QIAO Xiao-Jing ZHANG Jian-Guo YANG Li YU Wei 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第7期849-853,共5页
The title compound (C12H15NO13S, Mr = 413.31) was synthesized by the nitration of napthalene-1,4-dicarboxylate acid in mixed nitric and sulfuric acids. It crystallizes in monoclinic, space group P2 1/c with a = 8.10... The title compound (C12H15NO13S, Mr = 413.31) was synthesized by the nitration of napthalene-1,4-dicarboxylate acid in mixed nitric and sulfuric acids. It crystallizes in monoclinic, space group P2 1/c with a = 8.100(1), b = 24.369(3), c = 8.634(1) A, β = 105.380(2)°, V = 1643.1(4) A^3, Z = 4, Dc = 1.671 g/cm^3, F(000) = 856, μ(MoKa) = 0.273 mm^- 1, T = 294(2) K, the final R = 0.0400 and wR = 0.1021 for 2866 observed reflections with I 〉 2σ(I). In this crystal there exist a number of H-bonds which link the molecules to form a three-dimensional infinite network structure. The thermal decomposition of the title compound was investigated by using TG-DTG and DSC techniques. 展开更多
关键词 7-nitro-5-sulfo-napthalene-1 4-dicarboxylate acid crystal structure thermal analysis
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The Synthesis of Some Novel N-[α-(Isoflavone-7-O-) Acetyl]Amino Acid Derivatives 被引量:1
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作者 Peng LIU Jun Biao CHANG +2 位作者 Rong Feng CHEN Qiang WANG Jing Xi XIE (Henan Institute of Chemistry, Henan Academy of Science, Zhengzhou 450002 Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第5期391-394,共4页
A series of novel N-[α-(isoflavone-7-O-)acetyl] amino acid methyl esters were prepared from the efficient and regioselective alkylation of isoflavones with chloroacetyl amino acid derivatives under mild condition.
关键词 Isoflavone analogues N-[α-(isoflavone-7-O-)acetyl] amino acid methyl ester synthesis.
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EFFECT OF CIS-9, TRANS-11-CONJUGATED LINOLEIC ACID ON CELL CYCLE OF MAMMARY ADENOCARCINOMA CELLS(MCF-7) 被引量:1
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作者 刘家仁 陈炳卿 +3 位作者 韩晓辉 杨艳梅 郑玉梅 刘瑞海 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2002年第2期93-99,共7页
Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell ... Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B1, D1, p16ink4a and p21cip/waf1 of MCF-7 cells at various c9,t11-CLA concentrations (25μM, 50μM, 100μM and 200μM), at 24h and 48h. 96% ethand was used as negative control. Results: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9,t11-CLA. After treatment with various doses of c9,t11-CLA mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively. Inhibitory effect of c9,t11-CLA on DNA synthesis (except for 25μM, 24h) was demonstrated by significantly less incorporation of 3H-TdR than the negative control (P<0.05 and P<0.01). To further investigate the influence of the cell cycle progression, we found that c9,t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that incubation with different concentration of c9,t11-CLA at various times significantly decreased the expression of PCNA, Cyclin A, B1, D1 in MCF-7 cells compared to the negative control (P<0.01), whereas the expression of p16ink4a and p21cip/waf1, cyclin-dependent kinases inhibitors (CDKI), were increased. Conclusions: The cell growth and proliferation of MCF-7 cells is inhibited by c9,t11-CLA via blocking cell cycle, accompanying reduced expression of cyclin A, B1, D1 and enhanced expression of CDKI (p16ink4a and p21cip/waf1). 展开更多
关键词 Mammary adenocarcinoma cells (MCF-7) cis-9 trans-11-conjugated linoleic acid(c9 t11-CLA) IMMUNOCYTOCHEMISTRY Cell cycle Inhibition
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利用膜分散微反应器高效溶解D-7-ACA的研究 被引量:1
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作者 谢煜 张民 +2 位作者 胡卫国 王玉军 骆广生 《化工学报》 EI CSCD 北大核心 2023年第2期748-755,共8页
合成头孢呋辛的关键中间体3-去氨甲酰基头孢呋辛(DCC)由3-去乙酰基-7-氨基头孢烷酸(D-7-ACA)溶液与酰氯试剂缩合得到,其中利用高浓度NaOH溶液将D-7-ACA溶解在水和甲醇中是第一步。而D-7-ACA中的β-内酰胺环在强碱性条件下容易发生开环反... 合成头孢呋辛的关键中间体3-去氨甲酰基头孢呋辛(DCC)由3-去乙酰基-7-氨基头孢烷酸(D-7-ACA)溶液与酰氯试剂缩合得到,其中利用高浓度NaOH溶液将D-7-ACA溶解在水和甲醇中是第一步。而D-7-ACA中的β-内酰胺环在强碱性条件下容易发生开环反应,造成收率不高。传统反应釜不能精确控制体系的pH、混合效果差,因此溶解得到的D-7-ACA溶解浓度低。采用一种膜分散微反应器,实现了高效溶解D-7-ACA,并研究了D-7-ACA在不同初始浓度、不同温度和pH条件下的降解动力学。接着详细探讨了pH、温度和循环流速等因素对膜分散微反应器溶解D-7-ACA的影响。结果显示,利用膜分散微反应器在最优条件下得到的D-7-ACA溶解浓度为76.50 mg/ml,DCC收率为91.90%,相比传统搅拌法分别提高了5.91%和5.61%。 展开更多
关键词 溶解 降解动力学 微反应器 3-去乙酰基-7-氨基头孢烷酸 3-去氨甲酰基头孢呋辛
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The heading-date gene Ghd7 inhibits seed germination by modulating the balance between abscisic acid and gibberellins 被引量:1
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作者 Yong Hu Song Song +2 位作者 Xiaoyu Weng Aiqing You Yongzhong Xing 《The Crop Journal》 SCIE CSCD 2021年第2期297-304,共8页
Seed dormancy of cultivated rice was largely weakened during the progress of domestication.Correct timing and uniformity of seed germination are important for rapid seedling establishment and highyield production.In t... Seed dormancy of cultivated rice was largely weakened during the progress of domestication.Correct timing and uniformity of seed germination are important for rapid seedling establishment and highyield production.In the present study,we found that the heading-date gene Ghd7 acted as a negative regulator of germination.A mutant of ghd7 showed low sensitivity to exogenous ABA treatment during seed germination.Further investigation revealed reduced accumulation of ABA in mature ghd7 seeds as a consequence of dampened expression of OsNCED genes.Moreover,elevated GA_(3) level was detected in seeds of ghd7 mutant during imbibition course,which was attributed to the induction of genes responsible for the synthesis pathways of bioactive GAs.Thus,Ghd7 inhibits seed germination by increasing the ABA/GA_(3) ratio.Besides revealing pleiotropic effects of Ghd7,our results indicate its role in linking seed germination to growth-phase transition in rice,which would enrich the theoretical basis for future breeding practices. 展开更多
关键词 Ghd7 Seed germination Abscisic acid GIBBERELLINS ABA/GA_(3)ratio
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7-羟基-香豆素-3-羧酸衍生物的合成及抗肿瘤活性 被引量:1
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作者 顾宏霞 何冰 +3 位作者 谭鸿舟 严志奇 何黎琴 吴虹 《化学研究与应用》 CAS 北大核心 2023年第11期2711-2717,共7页
以2,4-二羟基苯甲醛和丙二酸二乙酯为起始原料,经Knoevenagel反应得到7-羟基-香豆素-3-羧酸乙酯(2);再经曼尼希反应、酯水解、酸化,得到7-羟基-8-氨甲基-香豆素-3羧酸(4a~4e);利用其羧基与不同碳数的二溴烷烃反应得到相应的溴代酯(5a~5... 以2,4-二羟基苯甲醛和丙二酸二乙酯为起始原料,经Knoevenagel反应得到7-羟基-香豆素-3-羧酸乙酯(2);再经曼尼希反应、酯水解、酸化,得到7-羟基-8-氨甲基-香豆素-3羧酸(4a~4e);利用其羧基与不同碳数的二溴烷烃反应得到相应的溴代酯(5a~5i),再与硝酸银反应得到9个有机硝酸酯类一氧化氮(NO)供体型7-羟基-香豆素-3羧酸衍生物(6a~6i)。目标化合物的结构经过核磁共振氢谱、碳谱和高分辨质谱确证。用MTT法评价了目标化合物对人肝癌HepG2细胞和人肺癌A549细胞增殖的影响,结果显示,所合成的目标化合物对受试的两种癌细胞均具有较强的增殖抑制作用,其中,化合物6c的活性最好。 展开更多
关键词 7-羟基-香豆素-3-羧酸 曼尼希碱 硝酸酯 NO供体 抗肿瘤活性
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