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Proteomics Study of Benzene Metabolite Hydroquinone Induced Hematotoxicity in K562 Cells
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作者 JIN Yi Shan YI Zong Chun +2 位作者 ZHANG Yu Jing RONG Long YU Chun Hong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第4期341-353,共13页
Objective Hydroquinone(HQ),one of the phenolic metabolites of benzene,is widely recognized as an important participant in benzene-induced hematotoxicity.However,there are few relevant proteomics in HQ-induced hematoto... Objective Hydroquinone(HQ),one of the phenolic metabolites of benzene,is widely recognized as an important participant in benzene-induced hematotoxicity.However,there are few relevant proteomics in HQ-induced hematotoxicity and the mechanism hasn’t been fully understood yet.Methods In this study,we treated K562 cells with 40μmol/L HQ for 72 h,examined and validated protein expression changes by Label-free proteomic analysis and Parallel reaction monitoring(PRM),and performed bioinformatics analysis to identify interaction networks.Results One hundred and eighty-seven upregulated differentially expressed proteins(DEPs)and 279 downregulated DEPs were identified in HQ-exposed K562 cells,which were involved in neutrophilmediated immunity,blood microparticle,and other GO terms,as well as the lysosome,metabolic,cell cycle,and cellular senescence-related pathways.Focusing on the 23 DEGs and 5 DEPs in erythroid differentiation-related pathways,we constructed the network of protein interactions and determined 6 DEPs(STAT1,STAT3,CASP3,KIT,STAT5B,and VEGFA)as main hub proteins with the most interactions,among which STATs made a central impact and may be potential biomarkers of HQ-induced hematotoxicity.Conclusion Our work reinforced the use of proteomics and bioinformatic approaches to advance knowledge on molecular mechanisms of HQ-induced hematotoxicity at the protein level and provide a valuable basis for further clarification. 展开更多
关键词 hydroquinonE PROTEOMICS HEMATOTOXICITY K562 cells
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The First Total Synthesis of Triprenylquinone and Hydroquinones
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作者 Chun Hong LI Xue Song CHEN +2 位作者 Guang Lian ZHOU Zhi Xiang XIE Ying LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第8期1024-1026,共3页
First total synthesis of triprenylquinone and hydroquinones, three naturally occurringcompound 1, 2 and (±) 3, have been achieved from readily available 2-bromo-5-methyl-1,4-dimethoxybenzene 4 and geranyl bromi... First total synthesis of triprenylquinone and hydroquinones, three naturally occurringcompound 1, 2 and (±) 3, have been achieved from readily available 2-bromo-5-methyl-1,4-dimethoxybenzene 4 and geranyl bromide. The triprenylquinone and hydroquinones precursor were readily prepared with use of a Julia reaction. 展开更多
关键词 Sesquiterpene triprenylquinones and hydroquinones total synthesis Julia coupling.
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小鼠白癜风疾病模型的构建及初步研究
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作者 曾令娥 李林英 +3 位作者 王世全 李海涛 王俊亚 赵艳芝 《现代中西医结合杂志》 CAS 2024年第11期1496-1500,共5页
目的比较氢醌乳膏和莫诺苯宗乳膏诱导野生型C57BL/6J小鼠产生白癜风样表型的作用,构建组织病理学相似度高、脱色效果持久稳定且成本低、易操作的白癜风样小鼠模型,为选择白癜风疾病动物模型以研究人类白癜风疾病的发病机制以及药物治疗... 目的比较氢醌乳膏和莫诺苯宗乳膏诱导野生型C57BL/6J小鼠产生白癜风样表型的作用,构建组织病理学相似度高、脱色效果持久稳定且成本低、易操作的白癜风样小鼠模型,为选择白癜风疾病动物模型以研究人类白癜风疾病的发病机制以及药物治疗效果、药物作用机制提供依据。方法将30只C57BL/6J小鼠随机分为3组,每组10只。3组小鼠于背部相同部位去毛后,对照组涂抹乳膏基质,莫诺苯宗组涂抹40%莫诺苯宗乳膏,氢醌组涂抹2.5%氢醌乳膏,均1次/d,建模周期为50 d。肉眼观察造模部位皮肤变化;建模结束后处死各组小鼠,取病变部位皮肤组织,进行酪氨酸酶(TYR)免疫荧光染色观察;摘眼球取血,ELISA法检测血清中TYR、干扰素-γ(IFN-γ)、肿瘤坏死因子-α(TNF-α)、基质金属蛋白酶-9(MMP-9)水平。结果莫诺苯宗组和氢醌组小鼠均出现明显皮肤脱色,TYR表达平均光密度值明显降低。莫诺苯宗组和氢醌组小鼠血清TYR水平均明显低于对照组(P均<0.05),莫诺苯宗组和氢醌组比较差异无统计学意义(P>0.05);氢醌组小鼠血清IFN-γ、MMP-9水平均明显高于对照组和莫诺苯宗组(P均<0.05),血清TNF-α水平与对照组比较差异无统计学意义(P>0.05);莫诺苯宗组小鼠血清TNF-α水平明显高于对照组(P均<0.05),血清IFN-γ、MMP-9水平与对照组比较差异均无统计学意义(P均>0.05)。结论2.5%氢醌乳膏和40%莫诺苯宗乳膏涂抹法均可成功建立野生型C57BL/6J小鼠白癜风模型,其中2.5%氢醌乳膏更易诱导建立白癜风表观模型。 展开更多
关键词 白癜风 氢醌 莫诺苯宗 C57BL/6J小鼠 干扰素-Γ 基质金属蛋白酶-9
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苯酚选择性氧化还原合成对苯二酚研究
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作者 王芳 黄杰军 +1 位作者 徐林 刘相李 《广州化工》 CAS 2024年第2期137-139,共3页
苯酚选择性氧化还原制备对苯二酚反应具有潜在的工业应用价值。本文使用复合型催化剂有机硒醚/CNTs将苯酚选择性地定向氧化为对苯醌,对苯醌在Pt/C催化剂的作用下还原为对苯二酚。为了提高对苯醌的收率,本文将硒催化组分固定在中空多孔... 苯酚选择性氧化还原制备对苯二酚反应具有潜在的工业应用价值。本文使用复合型催化剂有机硒醚/CNTs将苯酚选择性地定向氧化为对苯醌,对苯醌在Pt/C催化剂的作用下还原为对苯二酚。为了提高对苯醌的收率,本文将硒催化组分固定在中空多孔的碳纳米管上以增大催化剂的比表面积,苯酚氧化制备对苯醌选择性高达92.5%,具有催化剂制备简单、原料转化率和产物选择性高和废水排放量少等优势。 展开更多
关键词 苯酚 氧化还原 对苯醌 对苯二酚
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特丁基对苯二酚在不同油脂贮存过程中转化产物的识别、分离与鉴定 被引量:1
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作者 徐梦琪 祝振杰 +2 位作者 陈小军 李军 毕艳兰 《食品科学》 EI CAS CSCD 北大核心 2024年第4期42-49,共8页
以猪油、大豆油和棕榈油为实验原料,模拟贮存过程,分析不同种类油脂贮存过程中特丁基对苯二酚(tert-butylhydroquinone,TBHQ)转化情况。结果表明:随着贮存时间的延长,油样中TBHQ的剩余量及转化的叔丁基对苯醌(2-tert-butyl-1,4-benzoqui... 以猪油、大豆油和棕榈油为实验原料,模拟贮存过程,分析不同种类油脂贮存过程中特丁基对苯二酚(tert-butylhydroquinone,TBHQ)转化情况。结果表明:随着贮存时间的延长,油样中TBHQ的剩余量及转化的叔丁基对苯醌(2-tert-butyl-1,4-benzoquinone,TBBQ)量之和小于TBHQ原始添加量,并在不同油样甲醇提取液的气相色谱图中均发现除TBHQ和TBBQ之外相同的色谱峰。采用液相色谱分别分离纯化出未知色谱峰,并采用超高效液相色谱-四极杆-飞行时间质谱、核磁共振仪、紫外光谱仪和傅里叶变换红外光谱仪对未知化合物结构进行鉴定与表征,结果证明TBHQ在不同油脂中的转化产物相同,除TBBQ外均含有另一转化产物2-(2-甲基烯丙基)氢醌。 展开更多
关键词 特丁基对苯二酚 叔丁基对苯醌 2-(2-甲基烯丙基)氢醌 分离纯化 结构鉴定
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对苯二酚树脂的制备及其电化学性能研究
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作者 胡鹏涛 周立民 +2 位作者 陈龙 刘雨 郭雅妮 《武汉工程大学学报》 CAS 2024年第3期280-284,共5页
以对苯二酚、甲醛和对甲基苯酚为原料,在酸性条件下通过缩聚反应合成了一种对苯二酚树脂。通过傅里叶变换红外光谱和紫外-可见吸收光谱表征了所得聚合物的结构,采用热失重分析考察了聚合物的热稳定性能,利用循环伏安测试和恒电流充放电... 以对苯二酚、甲醛和对甲基苯酚为原料,在酸性条件下通过缩聚反应合成了一种对苯二酚树脂。通过傅里叶变换红外光谱和紫外-可见吸收光谱表征了所得聚合物的结构,采用热失重分析考察了聚合物的热稳定性能,利用循环伏安测试和恒电流充放电测试研究了聚合物的电化学性能。结果表明:合成的聚合物为目标产物,且拥有良好的热稳定性;在0.5 mol/L的Na_(2)SO_(4)溶液中,聚合物发生了可逆的氧化还原反应。在5 mV/s的扫描速率下,其比容量为69.72(mA·h)/g;在0.5 A/g的电流密度下,其比容量为78.23(mA·h)/g,经过100次充放电后,电容量保持率为66.2%,说明具有较高的循环使用寿命。 展开更多
关键词 对苯二酚 对甲基苯酚 甲醛 对苯二酚-甲醛树脂 电化学性能
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MOFs衍生的Fe-N-C纳米酶用于对苯二酚的比色检测
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作者 张元杰 李金凯 刘宗明 《中国粉体技术》 CAS CSCD 2024年第4期128-138,共11页
【目的】建立一种方便的检测对苯二酚(hydroquinone,HQ)的方法。【方法】采用化学掺杂法合成Fe-ZIF-8前驱体,对前驱体热解处理,得到Fe-N-C纳米酶粉末;通过活性对比、自由基捕获和动力学实验,系统探究Fe-N-C的类酶活性;依据HQ具有还原性... 【目的】建立一种方便的检测对苯二酚(hydroquinone,HQ)的方法。【方法】采用化学掺杂法合成Fe-ZIF-8前驱体,对前驱体热解处理,得到Fe-N-C纳米酶粉末;通过活性对比、自由基捕获和动力学实验,系统探究Fe-N-C的类酶活性;依据HQ具有还原性强、可将3,3',5,5'-四甲基联苯胺(TMB)显色体系还原为无色状态的特性,构建比色法检测HQ的传感平台。【结果】Fe-N-C表现出优异的过氧化物酶样活性,可以快速将显色底物TMB催化氧化为蓝色;Fe-N_(x)是Fe-N-C主要的活性位点,羟基自由基(•OH)、超氧自由基(O_(2)^(•−))和单线态氧(^(1)O_(2))是起主要作用的活性氧;Fe-N-C纳米酶对TMB的亲和力优于天然辣根过氧化物酶,该方法检测HQ的线性范围为0~33μmol/L,检测限为0.356μmol/L,同时具有良好的抗干扰能力。【结论】构建一种用于环境分析的金属有机骨架化合物(metal organic framework,MOFs)衍生物纳米酶,可实现HQ的简单和灵敏检测。 展开更多
关键词 纳米酶 金属-有机骨架 比色检测 对苯二酚
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HQEE改性PCL基形状记忆聚氨酯的制备
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作者 刘佩佩 关静 +2 位作者 曾鑫志 于佳宏 张彦飞 《工程塑料应用》 CAS CSCD 北大核心 2024年第5期7-13,共7页
聚(ε-己内酯)(PCL)是一种半结晶性聚合物,由于其具有良好的可降解性和形状记忆性能,PCL的改性被广泛关注和研究。通过分子交联的方式将氢醌-双(β-羟乙基)醚(HQEE)引入一种具有树枝状拓扑结构的PCL基形状记忆聚氨酯。其中,六亚甲基二... 聚(ε-己内酯)(PCL)是一种半结晶性聚合物,由于其具有良好的可降解性和形状记忆性能,PCL的改性被广泛关注和研究。通过分子交联的方式将氢醌-双(β-羟乙基)醚(HQEE)引入一种具有树枝状拓扑结构的PCL基形状记忆聚氨酯。其中,六亚甲基二异氰酸酯作为固化剂、三羟甲基丙烷(TMP)作为交联剂。用傅里叶变换红外光谱分析、X射线衍射光谱分析、热重分析、差示扫描量热分析和形状记忆性能分析表征所制备的形状记忆聚氨酯(SMPU)。分析结果表明,异氰酸酯(—NCO)活性基团全部参与反应,成功制备得到SMPU试样。所制备的SMPU均具有结晶性,且其结晶性能随扩链剂(HQEE和三甲基戊二醇)含量的升高而降低,热降解性能良好,在30.9~40.2℃范围内出现结晶/熔融峰,形状回复率均为100%,形状固定率和形状回复时间均随扩链剂含量的增大而减小。综合分析得到,试样SMPU-H2和SMPU-H3的结晶性能适中,表现出良好的形状记忆性能。其中,SMPU-H2和SMPU-H3的硬段含量分别为38.51%和46.39%,形状记忆转变温度分别为35.5,34.7℃。 展开更多
关键词 聚(ε-己内酯) 聚氨酯 形状记忆聚合物 氢醌-双(β-羟乙基)醚 结晶性 微相分离
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痰热清注射液治疗慢性阻塞性肺病急性加重期作用机制探讨
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作者 谭标标 任薇 《中医药临床杂志》 2024年第6期1081-1087,共7页
目的:研究痰热清注射液治疗慢性阻塞性肺病急性加重期作用机制。方法:在线查询TCMSP数据库、既往文献获取黄芩、熊胆粉、山羊角、金银花、连翘等中药的主要活性成分,利用swisstargetprediction数据库获取其活性成分对应靶点;利用GeneCa... 目的:研究痰热清注射液治疗慢性阻塞性肺病急性加重期作用机制。方法:在线查询TCMSP数据库、既往文献获取黄芩、熊胆粉、山羊角、金银花、连翘等中药的主要活性成分,利用swisstargetprediction数据库获取其活性成分对应靶点;利用GeneCards、OMMI、Drug Bank等数据库获取慢性阻塞性肺病急性加重期靶点。利用Venny平台在线获取药物与疾病靶点交集,通过DAVID数据库对相交靶点进行基因本体分析和通路富集分析,使用STRING数据库构建蛋白相互作用网络,借助Cytoscapr软件行可视化处理并筛选主要活性成分、关键靶点。最后通过AutoDock vina软件将核心靶点与核心成分进行分子对接验证,并利用pymol可视化处理。结果:痰热清注射液中含主要活性成分90个,对应靶点557个;连翘、黄芩、金银花为痰热清注射液的关键作用药物;baicalein、Norwogonin、5,7,4’-Trihydroxy-8-methoxyflavone、5,2’,6’-Trihydroxy-7,8-dimethoxyflavone、(2R)-7-hydroxy-5-methoxy-2-phenylchroman-4-one、Panicolin、Skullcapflavone II、Moslosooflavone、5,7,2,5-tetrahydroxy-8,6-dimethoxyflavone、quercetin等为核心活性成分;STAT3、HSP90AA1、ESR1、SRC、EP300、AKT1、JUN、PIK3R1、RELA等靶点为蛋白互作网络中的核心靶点。结论:痰热清注射液治疗主要通过黄酮类物质调节细胞炎症反应、细胞增殖、凋亡等对慢性阻塞性肺病急性加重期发挥潜在作用。 展开更多
关键词 痰热清注射液 慢性阻塞性肺病急性加重期 网络药理学 分子对接技术 作用机制
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Pd/γ-Al_(2)O_(3)催化剂作用下对苯醌加氢制备对苯二酚
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作者 何翌 陈臣举 张春雷 《上海师范大学学报(自然科学版中英文)》 2024年第1期62-66,共5页
采用浸渍法制备了负载型钯催化剂(Pd/γ-Al_(2)O_(3)),并将制备的催化剂应用于对苯醌加氢制备对苯二酚反应.考察了不同反应温度、压力、时间、催化剂用量等因素对Pd/γ-Al_(2)O_(3)催化剂性能的影响.以甲醇(CH4O)作为溶剂,在反应温度为3... 采用浸渍法制备了负载型钯催化剂(Pd/γ-Al_(2)O_(3)),并将制备的催化剂应用于对苯醌加氢制备对苯二酚反应.考察了不同反应温度、压力、时间、催化剂用量等因素对Pd/γ-Al_(2)O_(3)催化剂性能的影响.以甲醇(CH4O)作为溶剂,在反应温度为30℃、氢气(H2)压力为3.0 MPa、反应时间为2 h、对苯醌和甲醇的质量比m(对苯醌)∶m(甲醇)=3∶47、催化剂质量分数仅为0.25%(以对苯醌质量计)的条件下,对苯醌转化率为100%,对苯二酚的选择性为96.9%,产率为96.9%. 展开更多
关键词 对苯醌 催化加氢 对苯二酚 钯(Pd)催化剂
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多壁碳纳米管/PEDOT复合修饰电极的制备及对苯二酚的测定
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作者 邱善广 张胜健 《山西化工》 CAS 2024年第1期33-36,共4页
采用循环伏安法和悬凃法,在玻碳电极表面进行聚(3,4)-乙撑二氧噻吩(PEDOT)和多壁碳纳米管修饰,制备多壁碳纳米管-聚(3,4)-乙撑二氧噻吩复合修饰电极。通过扫描电镜观察复合电极的表面形貌,通过电化学阻抗谱(EIS)和循环伏安(CV)对复合电... 采用循环伏安法和悬凃法,在玻碳电极表面进行聚(3,4)-乙撑二氧噻吩(PEDOT)和多壁碳纳米管修饰,制备多壁碳纳米管-聚(3,4)-乙撑二氧噻吩复合修饰电极。通过扫描电镜观察复合电极的表面形貌,通过电化学阻抗谱(EIS)和循环伏安(CV)对复合电极进行电化学表征,用差分脉冲法(DPV)研究对苯二酚浓度与峰电流之间的线性关系。实验结果表明,制备的复合修饰电极对对苯二酚有明显的电催化作用,氧化还原峰电流明显增大;在p H为7.0的磷酸缓冲液(PBS)里,对苯二酚的峰电流最大。在1×10^(-5)~5×10^(-4)mol/L对苯二酚的浓度范围内,复合修饰电极的氧化峰电流值与浓度呈线性关系,其线性方程为y=47.95+0.0979x,R2=0.961,检出限为1.9×10^(-6)mol/L。制备的复合修饰电极能够增强电化学信号,具有较好的稳定性。 展开更多
关键词 多壁碳纳米管 PEDOT 修饰电极 对苯二酚
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基于网络药理学及分子对接探讨二至丸治疗早发性卵巢功能不全的作用机制
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作者 简万妍 王艳群 +1 位作者 陈美玲 曾莉 《中国医药科学》 2024年第7期77-81,共5页
目的基于网络药理学方法探讨二至丸治疗早发性卵巢功能不全(POI)的可能分子作用机制。方法使用网络药理学平台(TCMSP)采集二至丸的有效成分和相关的基因;通过基因组注释数据平台(GeneCards)、人类孟德尔遗传数据库(OMIM)数据库获取POI... 目的基于网络药理学方法探讨二至丸治疗早发性卵巢功能不全(POI)的可能分子作用机制。方法使用网络药理学平台(TCMSP)采集二至丸的有效成分和相关的基因;通过基因组注释数据平台(GeneCards)、人类孟德尔遗传数据库(OMIM)数据库获取POI疾病靶点;用蛋白互作网络数据库(STRING)构建蛋白质相互作用网络(PPI),通过CytoHubba筛选核心靶点。使用生物学信息注释数据库(DAVID)平台进行富集分析,采用Cytoscape 3.10.0软件进行拓扑学分析,利用AutoDockTools进行分子对接。结果二至丸内最主要的有效成分为槲皮素、木犀草素、山柰酚、刺槐素等,其中的AKT1、TP53等是关键靶点,包含的通路主要为PI3K-Akt信号通路、流体剪切应力和动脉粥样硬化信号通路等。分子对接验证大部分靶点与成分能进行有效结合。结论揭示二至丸能够经多种成分、靶点及多条信号通路对POI发挥协同治疗作用。 展开更多
关键词 二至丸 早发性卵巢功能不全 网络药理学 分子对接
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高效液相色谱法测定调味面制品中特丁基对苯二酚的含量
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作者 朱晓玲 《现代食品》 2024年第11期141-143,共3页
采用高效液相色谱法测定调味面制品中特丁基对苯二酚含量,样品经甲醇涡旋提取和离心处理后,使用C18色谱柱,流动相为甲醇+0.5%甲酸水(50+50),检测波长为280 nm,柱温为35℃,进行洗脱分离后上机测定。结果表明,特丁基对苯二酚浓度在0~400 m... 采用高效液相色谱法测定调味面制品中特丁基对苯二酚含量,样品经甲醇涡旋提取和离心处理后,使用C18色谱柱,流动相为甲醇+0.5%甲酸水(50+50),检测波长为280 nm,柱温为35℃,进行洗脱分离后上机测定。结果表明,特丁基对苯二酚浓度在0~400 mg·L^(-1)时,R^(2)=0.9995,线性关系良好,相对标准偏差为0.55%,加标回收率为90.9%~92.8%,适用于调味面制品中特丁基对苯二酚含量的准确测定。 展开更多
关键词 特丁基对苯二酚 高效液相色谱 调味面制品
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Possible Role of DNA Polymerase beta in Protecting Human Bronchial Epithelial Cells Against Cytotoxicity of Hydroquinone 被引量:2
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作者 DA-LIN HU HUAN-WEN TANG +11 位作者 HAI-RONG LIANG DONG-SHENG TANG YI-MING LIU WEI-DONG JI JIAN-HUI YUAN YUN HE ZHENG-Yu ZHU JIAN-PING YANG DAO-KUI FANG YAN SHA XIAO-ZHI TU ZHI-XIONG ZHUANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第2期171-177,共7页
Objective To explore the toxicological mechanism of hydroquinone in human bronchial epithelial cells and to investigate whether DNA polymerase beta is involved in protecting cells from damage caused by hydroquinone. M... Objective To explore the toxicological mechanism of hydroquinone in human bronchial epithelial cells and to investigate whether DNA polymerase beta is involved in protecting cells from damage caused by hydroquinone. Methods DNA polymerase beta knock-down cell line was established via RNA interference as an experimental group. Normal human bronchial epithelial cells and cells transfected with the empty vector of pEGFP-C1 were used as controls. Cells were treated with different concentrations of hydroquinone (ranged from 10 μmol/L to 120 μmol/L) for 4 hours. MTT assay and Comet assay [single-cell gel electrophoresis (SCGE)] were performed respectively to detect the toxicity of hydroquinone. Results assay showed that DNA polymerase beta knock-down cells treated with different concentrations of hydroquinone had a lower absorbance value at 490 nm than the control cells in a dose-dependant manner. Comet assay revealed that different concentrations of hydroquinone caused more severe DNA damage in DNA polymerase beta knock-down cell line than in control cells and there was no significant difference in the two control groups. Conclusions Hydroquinone has significant toxicity to human bronchial epithelial cells and causes DNA damage. DNA polymerase beta knock-down cell line appears more sensitive to hydroquinone than the control cells. The results suggest that DNA polymerase beta is involved in protecting cells from damage caused by hydroquinone. 展开更多
关键词 Human bronchial epithelial cells RNA interference hydroquinonE TOXICOLOGY DNA polymerase beta
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Electrochemistry of Hydroquinone Derivatives at Metal and Iodine-modified Metal Electrodes 被引量:1
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作者 HOU Peng HAN Dong-xue +1 位作者 NIU Li LIN Hai-bo 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第4期493-499,共7页
The difference in the electrochemical behavior of hydroquinone and pyrocatechol at platinum and gold surfaces was analyzed using voltammetry and attenuated total reflection Fourier transform infrared spectroscopy. The... The difference in the electrochemical behavior of hydroquinone and pyrocatechol at platinum and gold surfaces was analyzed using voltammetry and attenuated total reflection Fourier transform infrared spectroscopy. The results show that the hydroquinone derivatives are adsorbed on a gold surface with vertical orientation, which makes the electron transfer between the bulk species and the electrode surface easier than that in the case of flat adsorption of hydroquinone derivatives that occurs at a platinum electrode. The formation of the vertical conformation and the rapid process of electron transfer were also confirmed by quantum chemistry calculations. In addition, the pre-adsorbed iodine on the electrodes played a key role on the adsorbed configuration and electron transfer of redox species. 展开更多
关键词 hydroquinone derivatives Iodine-modified ELECTROCHEMISTRY
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Selection of the Mutants with High Hydroquinone Degradation Ability of Serratia Marcesscen by Plasma Mutation
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作者 姚日生 尤启冬 +1 位作者 何炜静 朱慧霞 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第3期364-367,共4页
In this study, an efficient way by plasma induced mutation was applied to improve the hydroquinone degradation capacity of Serratia marcescens AB 90027 (SM27). The results showed that combined with the selection of ... In this study, an efficient way by plasma induced mutation was applied to improve the hydroquinone degradation capacity of Serratia marcescens AB 90027 (SM27). The results showed that combined with the selection of hydroquinone tolerance, the mutant with high hy- droquinone degradation ability induced by plasma could be achieved. The best dose for plasma mutation was 15 s, which showed a 47.0% higher positive mutation ratio. Besides, the aimed mutant was markedly different from the parent strain (SM27) in colonial traits while cultivated on Kings media. Finally, the hydroquinone degradation ratio reached 70.5~o using the induced mutant strain with 1500 mg/L hydroquinone (HQ) after 15 days of cultivation as the selective conditions; however, it was only 46.7% for SM27. The improvement of the degradation capacity by the induced mutant with a high concentration of HQ selection was attributed to its faster growth and higher hydroquinone tolerance compared with that of the parent strain. 展开更多
关键词 serratia marcescens PLASMA MUTATION hydroquinone degradation
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Investigation of the oxidation of hydroquinone at the liquid/liquid interface
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作者 Lu, Xiao Quan Dong, De Fang +3 位作者 Liu, Xiu Hui Yao, Dong Na Wang, Wen Ting Xu, Yu Mei 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第2期225-228,共4页
The oxidation of hydroquinone(QH_2) was investigated for the first time at liquid/liquid(L/L) interface by scanning electrochemical microscopy(SECM).In this study,electron transfer(ET) from QH_2 in aqueous to ferrocen... The oxidation of hydroquinone(QH_2) was investigated for the first time at liquid/liquid(L/L) interface by scanning electrochemical microscopy(SECM).In this study,electron transfer(ET) from QH_2 in aqueous to ferrocene(Fc) in nitrobenzene (NB) was probed.The apparent heterogeneous rate constants for ET reactions were obtained by fitting the experimental approach curves to the theoretical values.The results showed that the rate constants for oxidation reaction of QH_2 were sensitive to the changes of the dri... 展开更多
关键词 SECM Electron transfer Liquid/liquid interface hydroquinonE
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An Estimation Study to Determine the Percentage of Hydroquinone Levels in situ Skin Lightening Creams Using GC-MS and HPLC Spectroscopic Instruments
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作者 Maha Abdallah Alnuwaiser 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2020年第6期1984-1987,共4页
Hydroquinone(HQ)is an phenolic aromatic compound used in cosmetic medicine as skin lightening material since long time ago.Accordingly the several pathological conditions that observed,the use of HQ for this purpose w... Hydroquinone(HQ)is an phenolic aromatic compound used in cosmetic medicine as skin lightening material since long time ago.Accordingly the several pathological conditions that observed,the use of HQ for this purpose was recently contraindicated.The commonly noted health problem associated with hydroquinone use was contact dermatitis.The present study was designed and conducted to determine the HQ presence and concentrations in ten samples of skin lightening cosmetics available in the local market.GC-MS analysis was employed for detection of HQ qualitatively while HPLC analysis was used as a quantitative analysis for determination of the HQ concentrations in each sample.The results obtained indicated that the overall range of HQ levels in all respected samples ranged from 0.0039%to 0.14%. 展开更多
关键词 Skin lightening COSMETICS hydroquinonE GC-MS HPLC Assay
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Chemical analysis of hydroquinone and retinoic acid contents in facial whitening creams
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作者 Aung Myo Htet Ei Ei Thin +1 位作者 Mi Mi Saw Soe Win 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2016年第1期89-90,共2页
Hydroquinone is potentially carcinogenic and is known to be a skin and respiratory irritant.Hydroquinone is carcinogenic it has been banned in some countries because of fears of a cancer risk[1,2].Animal studies have ... Hydroquinone is potentially carcinogenic and is known to be a skin and respiratory irritant.Hydroquinone is carcinogenic it has been banned in some countries because of fears of a cancer risk[1,2].Animal studies have shown that topically applied retinoic acid can be photocarcinogenic[3].The aim of this study was qualitative and quantitative determination of hydroquinone and retinoic acid contents in facial whitening creams by colour reaction tests,FT-IR after TLC separation and HPLC. 展开更多
关键词 hydroquinonE and RETINOIC ACID HPLC FACIAL WHITENING creams
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Molecular Cloning and Characterization of a Candidate Plant Growth-Related and Time-Keeping Constitutive Cell Surface Hydroquinone (NADH) Oxidase (ENOX1) from <i>Arabidopsis lyrata</i>
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作者 Xiaoyu Tang Laura M. C. Ades +1 位作者 Dorothy M. Morré D. James Morré 《Advances in Biological Chemistry》 2015年第1期1-15,共15页
ENOX (ECTO-NOX) proteins are proteins of the external surface of the plasma membrane that catalyze oxidation of both NADH and hydroquinones as well as carry out protein disulfidethiol interchange. They exhibit both pr... ENOX (ECTO-NOX) proteins are proteins of the external surface of the plasma membrane that catalyze oxidation of both NADH and hydroquinones as well as carry out protein disulfidethiol interchange. They exhibit both prion-like and time-keeping (clock) properties. The oxidative and interchange activities alternate to generate a regular period of 24 min in length. Here we report the cloning, expression, and characterization of a plant candidate constitutive ENOX (CNOX or ENOX1) protein from Arabidopsis lyrata. The gene encoding the 335 (165) amino acid protein is found in accession XP-002882467. Functional motifs characteristics of ENOX proteins previously identified by site-directed mutagenesis and present in the candidate ENOX1 protein from plants include adenine nucleotide and copper binding motifs along with essential cysteines. However, the drug binding motif (EEMTE) sequence of human ENOX2 is absent. The activities of the recombinant protein expressed in E. coli were unaffected by capsaicin, EGCg, and other ENOX2-inhibiting substances. Periodic oxidative activity was exhibited both with NAD(P)H and reduced coenzyme Q as substrate. Bound copper was necessary for activity and activity was inhibited by the ENOX1-specific inhibitor simalikalactone D. Addition of melatonin phased the 24-min period such that the next complete period began 24 min after the melatonin addition as appeared to be characteristic of ENOX1 activities in general. Periodic protein disulfide-thiol interchange activity also was demonstrated along with the 2 oxidative plus 3 interchange activity pattern characteristics of the 24-min ENOX1 protein period. Concentrated solutions of the purified plant ENOX1 protein formed insoluble aggregates, devoid of enzymatic activity, resembling amyloid. Activity was restored to aggregate preparations by isoelectric focusing. 展开更多
关键词 ENOX1 ECTO-NOX Proteins Plant Growth hydroquinonE (NADH) Oxidation Plasma Membrane Electron Transport Arabadopsis lyrata
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