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Angiotensin-converting enzyme 2 alleviates liver fibrosis through the renin-angiotensin system 被引量:1
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作者 Bai-Wei Zhao Ying-Jia Chen +2 位作者 Ruo-Peng Zhang Yong-Ming Chen Bo-Wen Huang 《World Journal of Gastroenterology》 SCIE CAS 2024年第6期607-609,共3页
The present letter to the editor is related to the study titled‘Angiotensin-converting enzyme 2 improves liver fibrosis in mice by regulating autophagy of hepatic stellate cells’.Angiotensin-converting enzyme 2 can ... The present letter to the editor is related to the study titled‘Angiotensin-converting enzyme 2 improves liver fibrosis in mice by regulating autophagy of hepatic stellate cells’.Angiotensin-converting enzyme 2 can alleviate liver fibrosis by regulating autophagy of hepatic stellate cells and affecting the renin-angiotensin system. 展开更多
关键词 Angiotensin-converting enzyme 2 Hepatic stellate cells Liver fibrosis Angiotensin II Angiotensin 1-7 Renin-angiotensin system
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Timosaponin AⅢ induces drug-metabolizing enzymes by activating constitutive androstane receptor (CAR) via dephosphorylation of the EGFR signaling pathway 被引量:1
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作者 Muhammad Zubair Hafiz Jie Pan +4 位作者 Zhiwei Gao Ying Huo Haobin Wang Wei Liu Jian Yang 《Journal of Biomedical Research》 CAS CSCD 2024年第4期382-396,共15页
The current study aimed to assess the effect of timosaponin AⅢ(T-AⅢ)on drug-metabolizing enzymes during anticancer therapy.The in vivo experiments were conducted on nude and ICR mice.Following a 24-day administratio... The current study aimed to assess the effect of timosaponin AⅢ(T-AⅢ)on drug-metabolizing enzymes during anticancer therapy.The in vivo experiments were conducted on nude and ICR mice.Following a 24-day administration of T-AⅢ,the nude mice exhibited an induction of CYP2B10,MDR1,and CYP3A11 expression in the liver tissues.In the ICR mice,the expression levels of CYP2B10 and MDR1 increased after a three-day T-AⅢ administration.The in vitro assessments with HepG2 cells revealed that T-AⅢ induced the expression of CYP2B6,MDR1,and CYP3A4,along with constitutive androstane receptor(CAR)activation.Treatment with CAR siRNA reversed the T-AⅢ-induced increases in CYP2B6 and CYP3A4 expression.Furthermore,other CAR target genes also showed a significant increase in the expression.The up-regulation of murine CAR was observed in the liver tissues of both nude and ICR mice.Subsequent findings demonstrated that T-AⅢ activated CAR by inhibiting ERK1/2 phosphorylation,with this effect being partially reversed by the ERK activator t-BHQ.Inhibition of the ERK1/2 signaling pathway was also observed in vivo.Additionally,T-AⅢ inhibited the phosphorylation of EGFR at Tyr1173 and Tyr845,and suppressed EGF-induced phosphorylation of EGFR,ERK,and CAR.In the nude mice,T-AⅢ also inhibited EGFR phosphorylation.These results collectively indicate that T-AⅢ is a novel CAR activator through inhibition of the EGFR pathway. 展开更多
关键词 timosaponin AⅢ CAR metabolism enzyme ERK1/2 signaling pathway EGFR signaling pathway
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伏马菌素B_(1)脱毒研究进展
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作者 李露露 王硕 +1 位作者 王晓萱 龙淼 《动物营养学报》 CAS CSCD 北大核心 2024年第1期115-123,共9页
伏马菌素B_(1)(FB_(1))是由镰刀菌产生的水溶性代谢产物,存在于镰刀菌污染了的谷物、油料作物、坚果、饲草和饲料中,是常见的真菌毒素之一。FB_(1)会对神经系统、呼吸系统、消化系统和生殖系统产生不同毒性作用,给农牧业造成不可估量的... 伏马菌素B_(1)(FB_(1))是由镰刀菌产生的水溶性代谢产物,存在于镰刀菌污染了的谷物、油料作物、坚果、饲草和饲料中,是常见的真菌毒素之一。FB_(1)会对神经系统、呼吸系统、消化系统和生殖系统产生不同毒性作用,给农牧业造成不可估量的经济损失。如何对FB_(1)进行脱毒,以降低其毒性作用,是目前研究的热点。因此,本文对FB_(1)的物理脱毒、化学脱毒、生物脱毒及其应用进行综述,重点对常用于FB_(1)生物脱毒的菌株和酶及其脱毒效果、脱毒机制进行了深入探讨,以期为提高FB_(1)脱毒效率和开发新的FB_(1)脱毒方法提供参考和思路。 展开更多
关键词 伏马菌素B_(1) 饲料 脱毒 微生物
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1-MCP协同活性炭处理抑制鲜切胡萝卜木质化形成研究
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作者 汤尧 李朝哲 +6 位作者 刘春雨 李学进 罗生虎 沈建铎 刘媛媛 马洁 韩泽云 《西华大学学报(自然科学版)》 CAS 2024年第4期44-52,共9页
鲜切胡萝卜在贮藏过程易发生木质化,导致品质下降。为探究1-MCP协同活性炭处理对鲜切胡萝卜木质化抑制保鲜效果,文章分析了乙烯利、活性炭、1-MCP和1-MCP协同活性炭等4种处理方式对鲜切胡萝卜硬度、总酚、抗氧化性、PPO、POD、PAL和木... 鲜切胡萝卜在贮藏过程易发生木质化,导致品质下降。为探究1-MCP协同活性炭处理对鲜切胡萝卜木质化抑制保鲜效果,文章分析了乙烯利、活性炭、1-MCP和1-MCP协同活性炭等4种处理方式对鲜切胡萝卜硬度、总酚、抗氧化性、PPO、POD、PAL和木质素含量的影响。结果表明:1-MCP协同活性炭处理显著延缓了胡萝卜硬度下降;在贮藏第10 d总酚含量达0.20 mg GAE·g^(−1),显著高于其他处理组(P<0.05);抗氧化性也保持最高水平;DPPH自由基清除活性为0.90μmol TE·g^(−1);PPO、POD活性分别为0.23 U·g^(−1)和61.08 U·g^(−1),显著低于对照组(P<0.05);PAL活性和木质素含量分别为81.67 U·g^(−1)和65.88 mg·g^(−1),也显著低于对照组(P<0.05)。可见,1-MCP协同活性炭处理可有效抑制鲜切胡萝卜木质化,提升其贮藏品质。 展开更多
关键词 1-MCP 活性炭 DPPH 酶活 木质化 鲜切胡萝卜
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肌醇需求酶1信号通路在自噬改善大鼠冠心病心肌缺血损伤中的作用
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作者 尹磊 王剑 +2 位作者 金静 章若涵 刘燕飞 《中国循环杂志》 CSCD 北大核心 2024年第5期503-510,共8页
目的:基于探讨肌醇需求酶1(IRE1)信号通路在自噬改善大鼠冠心病心肌缺血损伤中的作用。方法:将H9c2细胞分为对照组、IRE1组、缺氧缺糖(OGD)/复氧(OGD/R)组、OGD/R+IRE1组、氯喹组、IRE1+氯喹组、OGD/R+氯喹组、OGD/R+IRE1+氯喹组、OGD组... 目的:基于探讨肌醇需求酶1(IRE1)信号通路在自噬改善大鼠冠心病心肌缺血损伤中的作用。方法:将H9c2细胞分为对照组、IRE1组、缺氧缺糖(OGD)/复氧(OGD/R)组、OGD/R+IRE1组、氯喹组、IRE1+氯喹组、OGD/R+氯喹组、OGD/R+IRE1+氯喹组、OGD组、OGD+氯喹组、OGD/R+IRE1+敲低X盒结合蛋白1(si-XBP1)组、OGD/R+IRE1+过表达X盒结合蛋白1(XBP1-OE)组。通过自噬双标腺病毒(Adv-RFP-GFP-LC3)评估各组细胞的自噬通量。通过免疫荧光和免疫印迹分析X盒结合蛋白1(XBP1)的核转位。另将32只成年雄性C57BL/6 J小鼠随机分为假手术组、缺血/再灌注(I/R)组、IRE1组和I/R+IRE1组,每组8只。通过超声心动图评估大鼠心功能。通过定量免疫印迹分析自噬相关蛋白。结果:(1)细胞试验:与OGD/R组比,OGD/R+IRE1组H9c2细胞中IRE1蛋白表达水平显著增加(P<0.001),微管相关蛋白轻链3蛋白Ⅱ(LC3Ⅱ)和泛素结合蛋白(p62)蛋白表达均显著降低(P均<0.05)。与OGD/R+氯喹组比,OGD/R+IRE1+氯喹组H9c2细胞中LC3Ⅱ和p62蛋白表达均显著增加(P均<0.05)。与对照组比,OGD/R组H9c2细胞中IRE1细胞核/细胞质荧光强度比显著增加(P<0.001);与OGD/R组比,OGD/R+IRE1组IRE1细胞核/细胞质荧光强度增加(P<0.001)。与OGD/R组比,OGD/R+IRE1组核蛋白中的XBP1水平增加(P<0.05)。与OGD/R+IRE1组比,OGD/R+IRE1+si-XBP1组黄色点状体显著减少(P<0.01),OGD/R+IRE1+XBP1-OE组黄色点状体显著增加(P<0.05)。(2)大鼠体内实验:与假手术组比,I/R组左心室射血分数和短轴缩短率均显著降低(P均<0.05)。与I/R组比,I/R+IRE1组心功能障碍改善(P均<0.05)。与假手术组比,I/R组心肌自噬空泡的数量、IRE1、LC3Ⅱ和p62表达均显著增加(P均<0.05)。与I/R组比,I/R+IRE1组心肌自噬空泡的数量、p62表达均显著降低(P均<0.05),心肌组织中IRE1、LC3Ⅱ的表达均增加(P均<0.05)。结论:IRE1通过促进XBP1的核转位恢复了OGD/R和I/R诱导的自噬通量阻断,自噬通量的恢复有助于保护心功能。 展开更多
关键词 肌醇需求酶1 心功能 心肌缺血/再灌注 缺氧缺糖/复氧 自噬通量
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急性胆囊炎患者胆囊切除术后血清CCK-8、TREM1水平与发生感染的关系
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作者 陈立坤 董彩丽 +4 位作者 顾春芳 杨淑红 尹玉杰 朱小静 渠兴甫 《检验医学与临床》 CAS 2024年第17期2476-2479,2485,共5页
目的分析急性胆囊炎(AC)患者胆囊切除术后血清胆囊收缩素-8(CCK-8)、髓系细胞触发受体1(TREM1)水平与发生感染的关系。方法将该院2020年12月至2022年12月收治的70例胆囊切除术后发生感染的AC患者纳入研究组,66例胆囊切除术后未发生感染... 目的分析急性胆囊炎(AC)患者胆囊切除术后血清胆囊收缩素-8(CCK-8)、髓系细胞触发受体1(TREM1)水平与发生感染的关系。方法将该院2020年12月至2022年12月收治的70例胆囊切除术后发生感染的AC患者纳入研究组,66例胆囊切除术后未发生感染的AC患者纳入对照组。采用酶联免疫吸附试验检测血清CCK-8、TREM1水平。采用Pearson相关分析胆囊切除术后发生感染AC患者血清中CCK-8、TREM1水平与炎症因子水平的相关性。采用受试者工作特征(ROC)曲线分析血清CCK-8、TREM1水平对AC患者胆囊切除术后发生感染的诊断价值。采用多因素Logistic回归分析AC患者胆囊切除术后感染的影响因素。结果研究组与对照组有胆囊结石、胆囊周边积液比例比较,差异均有统计学意义(P<0.05)。与对照组比较,研究组血清CCK-8水平明显降低,TREM1水平明显升高,差异均有统计学意义(P<0.05)。研究组C反应蛋白(CRP)、白细胞介素-8(IL-8)、肿瘤坏死因子-α(TNF-α)水平明显高于对照组,差异均有统计学意义(P<0.05)。胆囊切除术后发生感染的AC患者血清CCK-8水平与CRP、IL-8、TNF-α水平均呈负相关(P<0.05),TREM1水平与CRP、IL-8、TNF-α水平均呈正相关(P<0.05)。ROC曲线分析显示,血清CCK-8与TREM1联合检测诊断AC患者胆囊切除术后发生感染的曲线下面积(AUC)明显大于CCK-8、TREM1单独检测的AUC(Z=5.703,P<0.001;Z=4.584,P<0.001)。有胆囊结石、胆囊周边积液及血清CCK-8水平降低、血清TREM1水平升高均为AC患者胆囊切除术后发生感染的危险因素(P<0.05)。结论胆囊切除术后发生感染的AC患者血清CCK-8水平降低,TREM1水平升高,二者联合检测能够提高对AC患者胆囊切除术后发生感染的诊断价值。 展开更多
关键词 急性胆囊炎 胆囊收缩素-8 髓系细胞触发受体1 感染 酶联免疫吸附试验 胆囊切除术
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贝莱斯芽孢杆菌YH-1凝乳酶对切达干酪成熟特性及生物活性的影响 被引量:1
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作者 刘同吉 王艺会 +2 位作者 薛瑞 任青霞 杨贞耐 《食品与发酵工业》 CAS CSCD 北大核心 2024年第8期8-16,I0001,共10页
为了研究贝莱斯芽孢杆菌YH-1凝乳酶对切达干酪品质的影响,以商品凝乳酶制作的切达干酪(干酪A)为对照组,以70%的商品凝乳酶和30%的YH-1凝乳酶(干酪B),以及YH-1凝乳酶(干酪C)制作的切达干酪为实验组,比较3组干酪在4℃成熟12周过程中成熟... 为了研究贝莱斯芽孢杆菌YH-1凝乳酶对切达干酪品质的影响,以商品凝乳酶制作的切达干酪(干酪A)为对照组,以70%的商品凝乳酶和30%的YH-1凝乳酶(干酪B),以及YH-1凝乳酶(干酪C)制作的切达干酪为实验组,比较3组干酪在4℃成熟12周过程中成熟特性和生物活性的变化。结果表明,干酪A和干酪B在干酪得率、总蛋白含量和氯化钠含量等指标之间没有显著差异(P>0.05)。干酪C的得率和脂肪含量低于干酪A,但总蛋白含量更高。与干酪A相比,干酪C在成熟过程中水分含量和pH值显著偏低,其中乳酸乳球菌活菌数没有明显变化,但在第12周的pH 4.6可溶性氮含量和12%(体积分数)三氯乙酸可溶性氮含量高于干酪A。干酪C的硬度显著高于干酪A和干酪B,而干酪B中的游离氨基酸含量高于干酪C和干酪A。干酪B和干酪C在成熟过程中所产生的醇类、酮类、酸类、酯类和苯环类化合物的含量高于干酪A。干酪生物活性研究表明,用YH-1凝乳酶制作的切达干酪能提高干酪的抗氧化能力和铁离子螯合能力。因此,YH-1凝乳酶具有部分代替商品凝乳酶生产干酪的潜力。 展开更多
关键词 贝莱斯芽孢杆菌YH-1凝乳酶 切达干酪 成熟特性 生物活性
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Expression of interleukin 1β converting enzyme in 5-FU induced apoptosis in esophageal carcinoma cells 被引量:13
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作者 DENG Li Ying 1, ZHANG Yun Han 2, XU Ping 2, YANG Su Min 1 and YUAN Xue Bin 1 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第1期55-57,共3页
AIM To study the role of interleukin 1β converting enzyme (ICE) in antitumor drug induced apoptosis in tumor cells. METHODS Morphological changes in human esophageal carcinoma Eca 109 cells after treated with 5 ... AIM To study the role of interleukin 1β converting enzyme (ICE) in antitumor drug induced apoptosis in tumor cells. METHODS Morphological changes in human esophageal carcinoma Eca 109 cells after treated with 5 fluorouracil (5 FU) were observed under light and electron microscope. Expression of ICE in the tumor cells exposed to 5 FU was examined by the immunocytochemical method. RESULTS The cells treated with 5 FU displayed disappearance of nucleoli, chromatin gathering under nuclear envelope, karyorrhexis, budding and the formation of apoptotic bodies. The expression of ICE was negative in control cells, and 5 FU could induce the ICE expression in Eca 109 cells undergoing apoptosis. The number and the staining intensity of positive cells increased with the extension of action time. CONCLUSION 5 FU may induce apoptosis in human esophageal carcinoma Eca 109 cells; ICE gene may be involved in the regulation of 5 FU induced apoptosis; and ICE protein may mediate apoptosis induced by 5 FU. 展开更多
关键词 ESOPHAGEAL cancinoma cell line APOPTOSIS 5 fluorouracil INTERLEUKIN 1β CONVERTING enzyme
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Metal 2-Hydroxy-1-Naphthaldehyde Thiosemicarbazone (Me-HNT) Complexes-A New Kind of Biomimic Enzyme Catalyst 被引量:4
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作者 Ming DU Fang Zhen LIANG +4 位作者 Bo TANG Yun Jing LUO Han Xi SHEN Bin TENG Yan LIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第1期23-26,共4页
Metal (Me=Fe(III), Mo(VI), Mn(II), Co(II), Ni(II), Zn(II) and Cu(II)) 2-hydroxy-1-naphthaldehyde thiosemicarbazone complexes (MeHNT) were synthesized and used as mimic-enzyme catalysts to mimic the active group of hor... Metal (Me=Fe(III), Mo(VI), Mn(II), Co(II), Ni(II), Zn(II) and Cu(II)) 2-hydroxy-1-naphthaldehyde thiosemicarbazone complexes (MeHNT) were synthesized and used as mimic-enzyme catalysts to mimic the active group of horseradish peroxidase (HRP). The results showed that Fe-HNT, Mo-HNT are effective catalysts, which have similar catalytic activity as HRP. The sequence of catalytic activities of tested biomimic peroxidas is Mo-HNT > Fe-HNT > Zn-HNT > Ni-HNT > Mn-HNT. Among them, Fe-HNT is used as a mimic-enzyme catalyst in determination of ascorbic acid and glucose by coupling the catalytic reaction of glucose oxidase. 展开更多
关键词 biomimic enzyme catalytic activity metal 2-hydroxy-1-naphthaldehyde thiosemicarbazone complexes SPECTROPHOTOMETRY
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Effect of angiotensin Ⅱ type 1 receptor blocker and angiotensin converting enzyme inhibitor on the intraocular growth factors and their receptors in streptozotocin-induced diabetic rats 被引量:5
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作者 Ik Soo Byon Dong Hyun Lee +3 位作者 Eun Sook Jun Min Kyu Shin Sung Who Park Ji Eun Lee 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第6期896-901,共6页
AIM: To investigate the effect of angiotensin II type 1 receptor blocker (ARB) and angiotensin converting enzyme inhibitor (ACEI) on intraocular growth factors and their receptors in streptozotocin-induced diabet... AIM: To investigate the effect of angiotensin II type 1 receptor blocker (ARB) and angiotensin converting enzyme inhibitor (ACEI) on intraocular growth factors and their receptors in streptozotocin-induced diabetic rats. METHODS: Forty Sprague-Dawley rats were divided into 4 groups: control, diabetes mellitus (DM), candesartan- treated DM, and enalapril-treated DM (each group, n---10). After the induction of DM by streptozotocin, candesartan [ARB, 5 mg/(kg · d)] and enalapril [ACEI, 10 mg/(kg · d)] were administered to rats orally for 4Wko Vascular endothelial growth factor (VEGF) and angiotensin II (Ang II) concentrations in the vitreous were measured using enzyme-linked immunosorbent assays, and VEGF receptor 2 and angiotensin II type 1 receptor (ATIR) levels were assessed at week 4 by Western blotting. RESULTS: Vitreous Ang II levels were significantly higher in the DM group and candesartan-treated DM group than in the control (P=0.04 and 0.005, respectively). Vitreous ATIR increased significantly in DM compared to the other three groups (P〈0.007). Candesartan-treated DM rats showed higher vitreal ATIR concentration than the enalapril-treated DM group and control (P〈0.001 and P=0.005, respectively). No difference in vitreous Ang II and ATIR concentration was found between the enalapril- treated DM group and control. VEGF and its receptor were below the minimum detection limit in all 4 groups. CONCLUSION: Increased Ang II and ATIR in the hyperglycemic state indicate activated the intraocular renin-angiotensin system, which is inhibited more effectively by systemic ACEI than systemic ARB. 展开更多
关键词 angiotensin converting enzyme inhibitor angiotensin II type 1 receptor blocker diabetic rat intraocularrenin-angiotensin system
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Deubiquitinating enzyme regulation of the p53 pathway: A lesson from Otub1 被引量:10
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作者 Xiao-Xin Sun Mu-Shui Dai 《World Journal of Biological Chemistry》 CAS 2014年第2期75-84,共10页
Deubiquitination has emerged as an important mechanism of p53 regulation. A number of deubiquitinating enzymes(DUBs) from the ubiquitin-specific protease family have been shown to regulate the p53-MDM2-MDMX networks. ... Deubiquitination has emerged as an important mechanism of p53 regulation. A number of deubiquitinating enzymes(DUBs) from the ubiquitin-specific protease family have been shown to regulate the p53-MDM2-MDMX networks. We recently reported that Otub1, a DUB from the OTU-domain containing protease family, is a novel p53 regulator. Interestingly, Otub1 abrogates p53 ubiquitination and stabilizes and activates p53 in cells independently of its deubiquitinating enzyme activity. Instead, it does so by inhibiting the MDM2 cognate ubiquitin-conjugating enzyme(E2) UbcH5. Otub1 also regulates other biological signaling through this non-canonical mechanism, suppression of E2, including the inhibition of DNA-damage-induced chromatin ubiquitination. Thus, Otub1 evolves as a unique DUB that mainly suppresses E2 to regulate substrates. Here we review the current progress made towards the understanding of the complex regulation of the p53 tumor suppressor pathway by DUBs, the biological function of Otub1 including its positive regulation of p53, and the mechanistic insights into how Otub1 suppresses E2. 展开更多
关键词 p53 MDM2 UBIQUITINATION Deubiquitinating enzymeS Otub1 Cell CYCLE APOPTOSIS
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Elevated pancreatic enzymes, IgM, soluble interleukin-2 receptor in anti-GADab(+) type 1 diabetes 被引量:1
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作者 Hidekatsu Yanai Sumie Moriyama 《World Journal of Diabetes》 SCIE CAS 2011年第5期75-76,共2页
Type 1 diabetes can be classified into immune-mediated diabetes (type 1A) and idiopathic diabetes, which lacks immunological evidence for beta cell autoimmunity (type 1B). Type 1A diabetes is characterized by the pres... Type 1 diabetes can be classified into immune-mediated diabetes (type 1A) and idiopathic diabetes, which lacks immunological evidence for beta cell autoimmunity (type 1B). Type 1A diabetes is characterized by the presence of the anti-glutamic acid decarboxylase antibody (anti-GADab). Fulminant type 1 diabetes is classified as type 1B diabetes, and characterized by the absence of anti-GADab, flu-like symptoms, and elevated serum exocrine pancreatic enzymes. We report a type 1 diabetic patient who showed flu-like symptoms, elevated serum exocrine pancreatic enzymes, and an extremely high-titer of anti-GADab, manifesting the characteristics of both type 1A and fulminant type 1 diabetes. 展开更多
关键词 Anti-glutamic acid DECARBOXYLASE antibody EXOCRINE PANCREATIC enzymeS Type 1 diabetes Soluble INTERLEUKIN-2 receptor
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Mitochondrial malic enzyme 2 promotes breast cancer metastasis via stabilizing HIF-1α under hypoxia 被引量:3
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作者 Duo You Danfeng Du +3 位作者 Xueke Zhao Xinmin Li Minfeng Ying Xun Hu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2021年第3期308-322,共15页
Objective: α-ketoglutarate(α-KG) is the substrate to hydroxylate collagen and hypoxia-inducible factor-1α(HIF-1α), which are important for cancer metastasis. Previous studies have shown that the upregulation of co... Objective: α-ketoglutarate(α-KG) is the substrate to hydroxylate collagen and hypoxia-inducible factor-1α(HIF-1α), which are important for cancer metastasis. Previous studies have shown that the upregulation of collagen prolyl 4-hydroxylase in breast cancer cells stabilizes the expression of HIF-1α by depleting α-KG levels. We hypothesized that mitochondrial malic enzyme 2(ME2) might also affect HIF-1α expression via modulating α-KG levels in breast cancer cells.Methods: We evaluated ME2 protein expression in 100 breast cancer patients using immunohistochemistry and correlated with clinicopathological indicators. The effect of ME2 knockout on cancer metastasis was evaluated using an orthotopic breast cancer model. The effect of ME2 knockout or knockdown on the levels of α-KG and HIF-1α proteins in breast cancer cell lines was determined both in vitro and in vivo.Results: ME2 was found to be upregulated in the human breast cancerous tissues compared with the matched precancerous tissues(P<0.001). The elevated expression of ME2 was associated with a poor prognosis(P=0.019).ME2 upregulation was also related to lymph node metastasis(P=0.016), pathological staging(P=0.033), and vascular cancer embolus(P=0.014). Also, ME2 knockout significantly inhibited lung metastasis in vivo. In the tumors formed by ME2 knockout cells, the levels of α-KG were significantly increased and collagen hydroxylation level did not change significantly but HIF-1α protein expression was significantly decreased, compared to the control samples. In cell culture, cells with ME2 knockout or knockdown demonstrated significantly higher α-KG levels but significantly lower HIF-1α protein expression than control cells under hypoxia. Exogenous malate and α-KG exerted similar effect on HIF-1α in breast cancer cells to ME2 knockout or knockdown. Additionally,treatment with malate significantly decreased 4 T1 breast cancer lung metastasis. ME2 expression was associated with HIF-1α levels in human breast cancer samples(P=0.008).Conclusions: Our results provide evidence that upregulation of ME2 is associated with a poor prognosis of breast cancer patients and propose a mechanistic understanding of a link between ME2 and breast cancer metastasis. 展开更多
关键词 Malic enzyme 2 breast cancer METASTASIS MALATE Α-KETOGLUTARATE hypoxia-inducible factor-1α
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石蒜1-氨基环丙烷-1-羧酸合酶基因LrACS的克隆及功能鉴定
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作者 樊雅婷 李雪纯 +1 位作者 李晓丹 汪仁 《植物资源与环境学报》 CAS CSCD 北大核心 2024年第5期74-82,共9页
为了解1-氨基环丙烷-1-羧酸合酶(ACS)基因在石蒜〔Lycoris radiata(L'Hér.)Herb.〕乙烯合成中的作用,对石蒜ACS基因LrACS进行了克隆,并通过系统进化树和氨基酸序列比对分析明确LrACS与其他同源蛋白的进化关系。利用亚细胞定位... 为了解1-氨基环丙烷-1-羧酸合酶(ACS)基因在石蒜〔Lycoris radiata(L'Hér.)Herb.〕乙烯合成中的作用,对石蒜ACS基因LrACS进行了克隆,并通过系统进化树和氨基酸序列比对分析明确LrACS与其他同源蛋白的进化关系。利用亚细胞定位分析LrACS在细胞中的定位,对LrACS重组蛋白进行体外活性检测,并利用实时荧光定量逆转录PCR(qRT-PCR)分析不同生长时期LrACS的组织特异性表达。结果显示:LrACS的开放阅读框长度为1473 bp,编码490个氨基酸。LrACS的理论相对分子质量为54954.97,理论等电点为pI 8.21。系统进化树分析结果表明LrACS与忽地笑〔Lycoris aurea(L'Hér.)Herb.〕LaACS的亲缘关系最近,均属于Ⅰ型ACS蛋白。亚细胞定位结果显示LrACS主要定位于细胞质基质。体外活性检测结果证实LrACS重组蛋白能够催化S-腺苷甲硫氨酸(SAM)生成1-氨基环丙烷-1-羧酸(ACC)。qRT-PCR分析结果显示:LrACS在花期和叶期的石蒜各组织中均有表达,但其表达具有组织特异性,其中,花期花瓣中LrACS的相对表达量极显著(P<0.01)高于根、鳞茎、花茎,叶期根中LrACS的相对表达量极显著高于鳞茎和叶。综上所述,LrACS主要定位于细胞质基质并在石蒜不同生长时期行使催化SAM生成ACC的功能。 展开更多
关键词 石蒜 1-氨基环丙烷-1-羧酸(ACC) 1-氨基环丙烷-1-羧酸合酶(ACS) 亚细胞定位 酶活 功能鉴定
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伏马毒素B_(1)对棉铃虫生长发育、解毒酶系和抗氧化酶系的影响
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作者 肖宏丽 杨南 +3 位作者 赵倩倩 庞民好 唐博文 刘颖超 《中国生物防治学报》 CSCD 北大核心 2024年第3期600-607,共8页
玉米耕作模式的转变,使伏马毒素B_(1)成为棉铃虫需要面对的新环境因素。为明确棉铃虫对这种新环境因素的适应机制,本研究测定了饲喂伏马毒素B_(1)后棉铃虫的生长发育情况及体内解毒酶、抗氧化酶活性。自棉铃虫3龄幼虫连续摄入伏马毒素B_... 玉米耕作模式的转变,使伏马毒素B_(1)成为棉铃虫需要面对的新环境因素。为明确棉铃虫对这种新环境因素的适应机制,本研究测定了饲喂伏马毒素B_(1)后棉铃虫的生长发育情况及体内解毒酶、抗氧化酶活性。自棉铃虫3龄幼虫连续摄入伏马毒素B_(1)后,幼虫期7 d体质量增长量、产卵量及孵化率较对照组有不同程度的降低,棉铃虫化蛹之前的发育历期较对照组缩短,而蛹期却延长。不同浓度的伏马毒素B_(1)胁迫不同时间后棉铃虫体内酯酶的活性均显著升高,细胞色素P450和谷胱甘肽S-转移酶的活性有不同程度的变化;抗氧化酶系中,过氧化氢酶和超氧化物歧化酶活性在伏马毒素B_(1)胁迫1 d时较对照组均显著升高,过氧化物酶活性仅在高剂量处理5 d时显著升高。棉铃虫伏马毒素B_(1)耐受品系中羧酸酯酶、过氧化氢酶、过氧化物酶活性较敏感品系显著升高,分别上升75.40%、50.74%、117.21%。综上,摄入伏马毒素B_(1)后棉铃虫的生长发育受到影响,棉铃虫通过激活酯酶、过氧化氢酶、过氧化物酶等应对伏马毒素B1的胁迫。 展开更多
关键词 棉铃虫 伏马毒素B_(1) 生长发育 解毒酶 抗氧化酶
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Inositol-requiring enzyme 1α is required for gut development in Xenopus lavies embryos 被引量:1
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作者 Jing Guo Xin-Xin Li +4 位作者 Jiao-Jiao Feng Chen-Yang Yin XueJun Wang Ning Wang Li Yuan 《World Journal of Gastroenterology》 SCIE CAS 2013年第2期227-234,共8页
AIM:To investigate the role of inositol-requiring enzyme 1α(IRE1α) in gut development of Xenopus lavies embryos.METHODS:Xenopus embryos were obtained with in vitro fertilization and cultured in 0.1 × MBSH.One a... AIM:To investigate the role of inositol-requiring enzyme 1α(IRE1α) in gut development of Xenopus lavies embryos.METHODS:Xenopus embryos were obtained with in vitro fertilization and cultured in 0.1 × MBSH.One and half nanogram of IRE1α,1 ng of IRE1α-GR mRNA,1 ng of IRE1αΔC-GR mRNA,and 50 ng of IRE1α morpholino oligonucleotide(MO) or XBP1(C)MO were injected into four blastomeres at 4-cell stage for scoring the phenotype and marker gene analysis.To rescue the effect of IRE1α MO,1 ng of IRE1α-GR mRNA was coinjected with 50 ng of MO.For the activation of the GR-fusion proteins,dexamethasone was prepared as 5 mmol/L stock solutions in 100% ethanol and applied to the mRNA injected embryos at desired stages in a concentration of 10 μmol/L in 0.1 × MBSH.Embryos were kept in dexamethasone up to stage 41.Whole-mount in situ hybridization was used to determine specific gene expression,such as IRE1α,IRE1β,Xbra and Xsox17α.IRE1α protein expression during Xenopus embryogenesis was detected by Western blotting.RESULTS:In the whole-mount in situ hybridization analysis,xenopus IRE1α and IRE1β showed quite different expression pattern during tadpole stage.The relatively higher expression of IRE1α was observed in the pancreas,and significant transcription of IRE1β was found in the liver.IRE1α protein could be detected at all developmental stages analyzed,from stage 1 to stage 42.Gain-of-function assay showed that IRE1α mRNA injected embryos at tailbud stage were nearly normal and the expression of the pan-mesodermal marker gene Xbra and the endodermal gene Xsox17α at stage 10.5 was not significantly changed in embryos injected with IRE1α mRNA as compared to uninjected control embryos.And at tadpole stage,the embryos injected with IRE1α-GR mRNA did not display overt phenotype,such as gut-coiling defect.Loss-of-function assay demonstrated that the IRE1α MO injected embryos were morphologically normal before the tailbud stages.We did not observe a significant change of mesodermal and endodermal marker gene expression,while after stage 40,about 80% of the MO injected embryos exhibited dramatic gut defects in which the guts did not coil,but other structures outside the gastrointestinal tract were relatively normal.To test if the phenotypes were specifically caused by the knockdown of IRE1α,a rescue experiment was performed by co-injection of IRE1α-GR mRMA with IRE1α MO.The data obtained demonstrated that the gut coiling defect was rescued.The deletion mutant of IRE1α was constructed,consisting of the N-terminal part without the C-terminal kinase and RNase domains named IRE1αΔC,to investigate the functional domain of IRE1α.Injection of IRE1αΔCGR mRNA caused similar morphological alterations with gut malformation by interfering with the function of endogenous xIRE1α.In order to investigate if IRE1α/XBP1 pathway was involved in gut development,50 ng of XBP1 MO was injected and the results showed that knockdown of XBP1 resulted in similar morphological alterations with gut-coiling defect at tadpole stage.CONCLUSION:IRE1α is not required for germ layer formation but for gut development in Xenopus lavies and it may function via XBP1-dependent pathway. 展开更多
关键词 Inositol-requiring enzyme 1α XBP1 XENOPUS lavies GUT DEVELOPMENT
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七种蛋白酶抑制剂对多房棘球蚴DNA损伤诱导样1蛋白活性的影响
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作者 张生英 刘仲藜 +1 位作者 郭爱疆 王帅 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第5期2273-2280,共8页
目前,多房棘球蚴病(alveolar echinococcosis, AE)尚无有效药物治疗手段,迫切需要开发新型治疗药物。前期研究表明,HIV蛋白酶抑制剂(HIV protease inhibitors, HIV PIs)具有潜在抗寄生虫功能。本文旨在研究HIV PIs对Echinococcus multil... 目前,多房棘球蚴病(alveolar echinococcosis, AE)尚无有效药物治疗手段,迫切需要开发新型治疗药物。前期研究表明,HIV蛋白酶抑制剂(HIV protease inhibitors, HIV PIs)具有潜在抗寄生虫功能。本文旨在研究HIV PIs对Echinococcus multilocularis(Emu)DNA损伤诱导样1蛋白(DNA damage inducible 1 protein, Ddi1)活性的影响。本研究通过构建真核表达重组载体pFastBac1-Emu Ddi1,在昆虫细胞系Sf9细胞中表达筛选出P1代和P2代,纯化出可溶性Ddi1重组蛋白,然后与目的蛋白的荧光底物检测纯化蛋白的活性,进一步检测沙奎那韦(saquinavir, SQV)、利托那韦(ritonavir, RTV)、安普那韦(amprenavir, APV)、阿扎那韦(atazanavir, ATV)、洛匹那韦(lopinavir, LPV)、福沙那韦(fosamprenavir, Fos)、达芦那韦(darunavir, DRV)等7种HIV PIs对Emu Ddi1重组蛋白活性的抑制能力。结果显示:细胞系内真核表达产物的酶活Km为1.422μmol·L^(-1),具有良好的亲和力和活性,最终筛到沙奎那韦对Ddi1蛋白二聚体活性位点的抑制率达67%,其IC_(50)为34,说明沙奎那韦对Emu Ddi1重组蛋白酶活性具有良好的抑制效果。以上结果提示:沙奎那韦抑制重组蛋白Ddi1的活性,可能成为Ddi1的靶向药物,以期为替代药物或开发联合用药提供基础。 展开更多
关键词 蛋白酶抑制剂 多房棘球蚴 DNA损伤诱导样蛋白 酶活性 抑制率
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Repressing malic enzyme 1 redirects glucose metabolism,unbalances the redox state,and attenuates migratory and invasive abilities in nasopharyngeal carcinoma cell lines 被引量:4
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作者 Fang-Jing Zheng Hao-Bin Ye +3 位作者 Man-Si Wu Yi-Fan Lian Chao-Nan Qian Yi-Xin Zeng 《Chinese Journal of Cancer》 SCIE CAS CSCD 2012年第11期519-531,共13页
A large amount of nicotinamide adenine dinucleotide phosphate(NADPH) is required for fatty acid synthesis and maintenance of the redox state in cancer cells.Malic enzyme 1(ME1)-dependent NADPH production is one of the... A large amount of nicotinamide adenine dinucleotide phosphate(NADPH) is required for fatty acid synthesis and maintenance of the redox state in cancer cells.Malic enzyme 1(ME1)-dependent NADPH production is one of the three pathways that contribute to the formation of the cytosolic NADPH pool.ME1 is generally considered to be overexpressed in cancer cells to meet the high demand for increased de novo fatty acid synthesis.In the present study,we found that glucose induced higher ME1 activity and that repressing ME1 had a profound impact on glucose metabolism of nasopharyngeal carcinoma(NPC) cells.High incorporation of glucose and an enhancement of the pentose phosphate pathway were observed in ME1-repressed cells.However,there were no obvious changes in the other two pathways for glucose metabolism:glycolysis and oxidative phosphorylation.Interestingly,NADPH was decreased under low-glucose condition in ME1-repressed cells relative to wild-type cells,whereas no significant difference was observed under high-glucose condition.ME1-repressed cells had significantly decreased tolerance to low-glucose condition.Moreover,NADPH produced by ME1 was not only important for fatty acid synthesis but also essential for maintenance of the intracellular redox state and the protection of cells from oxidative stress.Furthermore,diminished migration and invasion were observed in ME1-repressed cells due to a reduced level of Snail protein.Collectively,these results suggest an essential role for ME1 in the production of cytosolic NADPH and maintenance of migratory and invasive abilities of NPC cells. 展开更多
关键词 氧化还原状态 鼻咽癌细胞 苹果酸酶 细胞株 葡萄糖 糖代谢 还原型烟酰胺腺嘌呤二核苷酸 侵袭
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心肌酶及sTREM-1、HMGB1在脓毒症心肌损伤患者预后评估中的应用
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作者 王云鹏 王跃玲 +3 位作者 吕旭方 张新蔚 马宝亮 徐丽 《河南医学研究》 CAS 2024年第13期2358-2361,共4页
目的探究心肌酶及血清可溶性髓样细胞触发受体-1(sTREM-1)、高迁移率族蛋白1(HMGB1)在脓毒症心肌损伤(SIMD)患者预后评估中的应用。方法回顾性分析河南大学第一附属医院2020年8月至2022年8月123例SIMD患者,根据患者预后情况分为死亡组(3... 目的探究心肌酶及血清可溶性髓样细胞触发受体-1(sTREM-1)、高迁移率族蛋白1(HMGB1)在脓毒症心肌损伤(SIMD)患者预后评估中的应用。方法回顾性分析河南大学第一附属医院2020年8月至2022年8月123例SIMD患者,根据患者预后情况分为死亡组(38例)与存活组(85例),比较两组一般资料、天冬氨酸转氨酶(AST)、乳酸脱氢酶(LDH)、肌酸激酶(CK)、心肌型肌酸激酶同工酶(CK-MB)、sTREM-1、HMGB1等,并分析其与预后的关系。结果死亡组急性生理学与慢性健康状况评分Ⅱ(APACHEⅡ)、序贯器官衰竭评分(SOFA)高于对照组(P<0.05);死亡组AST、CK、CK-MB水平高于存活组(P>0.05),但两组LDH水平差异无统计学意义(P>0.05);死亡组sTREM-1、HMGB1水平均高于对照组(P<0.05);Cox回归分析显示APACHEⅡ评分、SOFA评分、CK-MB、sTREM-1以及HMGB1与脓毒症心肌损伤患者预后密切相关(P<0.05)。结论心肌酶联合sTREM-1、HMGB1具有评估脓毒症心肌损伤患者的价值。 展开更多
关键词 脓毒症 心肌损伤 心肌酶 血清可溶性髓样细胞触发受体-1 高迁移率族蛋白1
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1-甲基环丙烯结合气调处理对‘帕拉英达’和‘吉禄’芒果保鲜效果的影响
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作者 杞廷美 李艳娇 +3 位作者 赵兴东 彭磊 林奇 包媛媛 《保鲜与加工》 CAS 北大核心 2024年第3期1-13,20,共14页
为探究1-甲基环丙烯(1-Methylcyclopropene,1-MCP)结合气调处理对采后‘帕拉英达’和‘吉禄’芒果贮藏品质的影响,以元江晚熟芒果品种‘帕拉英达’和‘吉禄’为试材,分别用0.5μL/L 1-MCP、微孔膜、PBI气调保鲜袋、1-MCP+微孔膜及1-MCP+... 为探究1-甲基环丙烯(1-Methylcyclopropene,1-MCP)结合气调处理对采后‘帕拉英达’和‘吉禄’芒果贮藏品质的影响,以元江晚熟芒果品种‘帕拉英达’和‘吉禄’为试材,分别用0.5μL/L 1-MCP、微孔膜、PBI气调保鲜袋、1-MCP+微孔膜及1-MCP+PBI气调保鲜袋对芒果进行处理,对其外观指标、失重率、硬度、可溶性固形物(TSS)含量、VC含量、可滴定酸(TA)含量、呼吸强度、商品率以及呼吸代谢相关酶活性变化进行检测分析。结果表明:在(13±1)℃贮藏过程中,与未作任何处理的对照组相比,5种处理在一定时间内均能延缓‘帕拉英达’和‘吉禄’果实黄化指数、病情指数、腐烂指数、色差、失重率、可溶性固形物含量和呼吸强度的上升,抑制果实硬度、VC含量、可滴定酸含量及商品率的下降,显著抑制果实呼吸代谢相关酶活性变化。综合分析,在(13±1)℃贮藏环境中,1-MCP+PBI气调保鲜袋处理对‘帕拉英达’和‘吉禄’芒果的保鲜效果最优,更有利于果实的贮藏。研究结果可为低纬度、高海拔地区晚熟芒果采后保鲜提供技术参考和科学依据。 展开更多
关键词 1-甲基环丙烯 微孔膜 PBI气调保鲜袋 自发气调 晚熟芒果 呼吸代谢酶 贮藏品质
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