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Thymosin Alpha-1 Inhibits Complete Freund's Adjuvant-Induced Pain and Production of Microglia-Mediated Pro-inflammatory Cytokines in Spinal Cord
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作者 Yunlong Xu Yanjun Jiang +10 位作者 Lin Wang Jiahua Huang Junmao Wen Hang Lv Xiaoli Wu Chaofan Wan Chuanxin Yu Wenjie Zhang Jiaying Zhao Yinqi Zhou Yongjun Chen 《神经科学通报:英文版》 SCIE CAS CSCD 2019年第4期637-648,共12页
Activation of inflammatory responses regulates the transmission of pain pathways through an integrated network in the peripheral and central nervous systems.The immunopotentiator thymosin alpha-1(Tal)has recently been... Activation of inflammatory responses regulates the transmission of pain pathways through an integrated network in the peripheral and central nervous systems.The immunopotentiator thymosin alpha-1(Tal)has recently been reported to have anti-inflammatory and neuroprotective functions in rodents.However,how Tα1 affects inflammatory pain remains unclear.In the present study,intraperitoneal injection of Tal attenuated complete Freund's adjuvant(CFA)-induced pain hypersensitivity,and decreased the up-regulation of pro-inflammatory cytokines(TNF-α,IL-1β,and IL-6)in inflamed skin and the spinal cord.We found that CFA-induced peripheral inflammation evoked strong microglial activation,but the effect was reversed by Tα1.Notably,Tα1 reversed the CFA-induced up-regulation of vesicular glutamate transporter(VGLUT)and down-regulated the vesicular γ-aminobutyric acid transporter(VGAT)in the spinal cord.Taken together,these results suggest that Tα1 plays a therapeutic role in inflammatory pain and in the modulation of microgliainduced pro-inflammatory cytokine production in addition to mediation of VGLUT and VGAT expression in the spinal cord. 展开更多
关键词 THYMOSIN alpha-1 CYTOKINE MICROGLIA Vesicular GLUTAMATE TRANSPORTER type 2 Vesicular γ-aminobutyric acid TRANSPORTER
Plant peroxisomal solute transporter proteins
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作者 Lennart Charton Anastasija Plett Nicole Linka 《植物学报:英文版》 SCIE CAS CSCD 2019年第7期817-835,共19页
Plant peroxisomes are unique subcellular organelles which play an indispensable role in several key metabolic pathways, including fatty acid b-oxidation,photorespiration, and degradation of reactive oxygen species. Th... Plant peroxisomes are unique subcellular organelles which play an indispensable role in several key metabolic pathways, including fatty acid b-oxidation,photorespiration, and degradation of reactive oxygen species. The compartmentalization of metabolic pathways into peroxisomes is a strategy for organizing the metabolic network and improving pathway efficiency. An important prerequisite, however, is the exchange of metabolites between peroxisomes and other cell compartments. Since the first studies in the 1970s scientists contributed to understanding how solutes enter or leave this organelle.This review gives an overview about our current knowledge of the solute permeability of peroxisomal membranes described in plants, yeast, mammals and other eukaryotes. In general, peroxisomes contain in their bilayer membrane specific transporters for hydrophobic fatty acids(ABC transporter) and large cofactor molecules(carrier for ATP, NAD and CoA). Smaller solutes with molecular masses below 300–400 Da, like the organic acids malate, oxaloacetate, and 2-oxoglutarate, are shuttled via non-selective channels across the peroxisomal membrane.In comparison to yeast, human, mammals and other eukaryotes, the function of these known peroxisomal transporters and channels in plants are discussed in this review. 展开更多
关键词 PLANT peroxisomal SOLUTE TRANSPORTER PROTEINS
ABCG2基因多态性与结直肠癌发生发展的相关性研究
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作者 张晓梅 孔晓玲 +8 位作者 洪伟伟 张琰 武渊 程艳萍 杨圣 许思易 刘桐 梁戈玉 沈波 《中国预防医学杂志》 CAS CSCD 2019年第4期265-270,共6页
目的探讨ABCG2基因rs2231137和rs2231142单核苷酸多态性(SNP)与结直肠癌发生发展的关系。方法选取2016年1月至2017年7月采用病例-对照研究,收集结直肠癌患者外周血样本690份,社区健康体检者外周血样本431份,使用TaqMan实时荧光定量PCR... 目的探讨ABCG2基因rs2231137和rs2231142单核苷酸多态性(SNP)与结直肠癌发生发展的关系。方法选取2016年1月至2017年7月采用病例-对照研究,收集结直肠癌患者外周血样本690份,社区健康体检者外周血样本431份,使用TaqMan实时荧光定量PCR方法进行基因分型,应用χ^2检验和logistic回归进行ABCG2 rs2231137和rs2231142基因多态性与结直肠癌关联分析。结果对性别和年龄进行分层分析显示,携带ABCG2 rs2231142 AA基因型的男性,与CC基因型相比,结直肠癌发病风险降低(OR=0.50,95%CI:0.28~0.90,P=0.022)。年龄≤60岁携带rs2231137 AA基因型的结直肠癌患者发生Ⅰ、Ⅱ期肿瘤的比例高于Ⅲ、Ⅳ期(OR=0.29,95%CI:0.14~0.61,P=0.001)。结论 ABCG2 rs2231137和rs2231142单核苷酸多态性与结直肠癌的发生发展相关。 展开更多
关键词 转运蛋白 ABCG2 单核苷酸多态性 结直肠癌 连锁不平衡
铝诱导植物根系分泌有机酸阴离子的机理及其调控(英文)
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作者 Jian-li YANG Wei FAN Shao-jian ZHENG 《浙江大学学报:B卷英文版》 SCIE CAS CSCD 2019年第6期513-527,共15页
铝是地壳中最丰富的金属元素。在pH低于5.5的酸性土壤中,部分含铝矿物中的铝会溶解进入土壤溶液,严重危害植物的生长和发育。一些植物能够进化出耐铝机理以制抵抗铝毒害。其中,铝诱导根系分泌有机酸阴离子(包括柠檬酸、苹果酸和草酸)是... 铝是地壳中最丰富的金属元素。在pH低于5.5的酸性土壤中,部分含铝矿物中的铝会溶解进入土壤溶液,严重危害植物的生长和发育。一些植物能够进化出耐铝机理以制抵抗铝毒害。其中,铝诱导根系分泌有机酸阴离子(包括柠檬酸、苹果酸和草酸)是证据最确凿的机理之一。分泌到胞外的有机酸阴离子可以通过螯合作用解除铝毒。编码铝诱导柠檬酸和苹果酸阴离子分泌的转运蛋白基因已被鉴定。同时,众多证据表明这些基因的表达调控与植物耐铝性密切相关。本文概述了近年来植物耐铝机理,特别是铝诱导植物根系分泌有机酸阴离子的生理机制的研究进展。重点总结了编码有机酸转运蛋白基因的鉴定,以及对这些基因表达调控的理解。本文也对调控有机酸转运蛋白基因表达的可能的信号通路作了讨论,并提出了该领域的研究展望。 展开更多
关键词 酸性土壤 铝毒 表达调控 有机酸阴离子 转运蛋白
不同类型淀粉及糖蛋白质比对鲤糖代谢能力的影响 预览
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作者 孙金辉 范泽 +3 位作者 崔培 程镇燕 白东清 乔秀亭 《大连海洋大学学报》 CAS CSCD 北大核心 2019年第2期220-227,共8页
为考察不同糖源对蛋白质的节约作用,以木薯淀粉(CS)和小麦淀粉(WS)为主要糖源,配制3组糖/蛋白质(C/P)比例分别为C5%/P32%、C10%/P30%、C20%/P28%的等能等脂饲料,以初始体质量为(55.73±3.55)g的鲤Cyprinus carpio作为养殖对象,在试... 为考察不同糖源对蛋白质的节约作用,以木薯淀粉(CS)和小麦淀粉(WS)为主要糖源,配制3组糖/蛋白质(C/P)比例分别为C5%/P32%、C10%/P30%、C20%/P28%的等能等脂饲料,以初始体质量为(55.73±3.55)g的鲤Cyprinus carpio作为养殖对象,在试验网箱中养殖8周。结果表明:CS、WS组中鲤肠道淀粉酶活性的最大值均出现在C10%/P30%组,显著高于C20%/P28%组(P<0.05);CS组中,C10%/P30%组鲤肝胰脏磷酸果糖激酶(PFK)、丙酮酸激酶(PK)活性显著高于C5%/P32%组(P<0.05),磷酸烯醇丙酮酸羧激酶(PEPCK)活性显著低于C5%/P32%组(P<0.05);鲤血清中胰岛素(INS)、胰高血糖素(GC)含量最高值分别出现在C10%/P30%和C20%/P28%组,显著高于其他两组(P<0.05);WS组中,C5%/P32%组鲤肝胰脏PFK、葡萄糖-6-磷酸脱氢酶(G6PD)、PEPCK、糖原合成酶(GS)活性显著高于C20%/P28%组(P<0.05);相同C/P比例条件下,CS组的葡萄糖含量显著低于WS组(P<0.05);CS组中,C10%/P30%组葡萄糖转运载体-2(GLUT2)及己糖激酶(HK)基因表达量显著高于其他两组(P<0.05),胰岛素受体(IR)基因表达量C10%/P30%组显著高于C5%/P32%组(P<0.05);而WS组中,各比例组IR、GLUT2及HK基因表达量均无显著性差异(P>0.05),相同C/P比例条件下,CS组的肠道钠钾葡萄糖共转运载体(SGLT1)基因表达量显著高于WS组(P<0.05)。研究表明,木薯淀粉及小麦淀粉对饲料蛋白质均有较好的节约作用,且木薯淀粉效果优于小麦淀粉。 展开更多
关键词 糖蛋白质比 淀粉类型 淀粉酶 糖代谢 转运载体
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乳酸菌代谢低聚糖机理的研究进展 预览
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作者 陈臣 卢艳青 +1 位作者 于海燕 田怀香 《中国食品学报》 EI CAS CSCD 北大核心 2019年第6期274-283,共10页
乳酸菌利用低聚糖是其在肠道中定殖并发挥益生活性的必要条件,对其代谢机理的认识对于探索肠道内微生物的生理活动规律,促进人体健康有重要意义。本文综述了乳酸菌代谢低聚糖的作用机理,分别从糖转运系统、糖基水解酶类和代谢调控等方... 乳酸菌利用低聚糖是其在肠道中定殖并发挥益生活性的必要条件,对其代谢机理的认识对于探索肠道内微生物的生理活动规律,促进人体健康有重要意义。本文综述了乳酸菌代谢低聚糖的作用机理,分别从糖转运系统、糖基水解酶类和代谢调控等方面对低聚果糖(FOS)、低聚半乳糖(GOS)、低聚木糖(XOS)、低聚异麦芽糖(IMO)、棉籽糖系列低聚糖(RFO)等代谢过程进行总结,并对未来的研究方向与热点进行展望。 展开更多
关键词 乳酸菌 低聚糖 转运系统 糖苷酶 代谢调控
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基于ANSYS的运输车车厢有限元分析 预览
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作者 刘轶菡 《客车技术》 2019年第2期21-23,27共4页
介绍了运输车结构及参数,对运输车车厢进行了有限元分析计算。重点阐述了铰链轴和副车架的优化及整车设计的再次优化校核,解决了因车厢重而导致的燃油消耗量大、运输效率低等问题。
关键词 运输车 有限元分析 ANSYS 优化设计
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内源性物质代谢对药物代谢处置的影响及机制研究 预览
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作者 陈泓竹 刘建明 +3 位作者 周芳 贾元威 王广基 张经纬 《中国临床药理学与治疗学》 CAS CSCD 2019年第5期580-588,共9页
内源性物质代谢是机体在细胞、分子等水平上对内外因素的应答过程,是机体自有成分对生理、疾病及外源物质作用的反馈。药物代谢处置是药物发挥药效和产生不良反应的前提。不同生理或疾病状态下,内源性物质代谢发生改变势必影响药物代谢... 内源性物质代谢是机体在细胞、分子等水平上对内外因素的应答过程,是机体自有成分对生理、疾病及外源物质作用的反馈。药物代谢处置是药物发挥药效和产生不良反应的前提。不同生理或疾病状态下,内源性物质代谢发生改变势必影响药物代谢处置,进而影响药效及不良反应。国内外研究表明,内源性物质代谢变化,可导致代谢通路中某些中间产物或终产物的含量改变,从而引起药物代谢酶和转运体的变化。本文就内源性糖代谢、脂代谢、核苷酸代谢、氨基酸代谢及激素等对药物代谢处置的影响及其机制进行综述,以期为不同生理及疾病状态下的临床安全用药和个体化治疗提供借鉴和思路。 展开更多
关键词 内源性物质代谢 药物代谢酶 转运体 临床安全用药
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治疗心血管疾病的中药组分对转运体的调节作用研究进展 预览
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作者 于楠 边原 《实用药物与临床》 CAS 2019年第5期553-557,共5页
药物在肝脏代谢过程中除代谢酶参与外,药物转运体同样也起着举足轻重的作用。除他汀类、沙坦类等心血管系统化学药对转运体会产生影响外,近年来的研究表明,一些常用于治疗心血管系统疾病的中药组分亦会影响转运体的摄取外排功能,在与西... 药物在肝脏代谢过程中除代谢酶参与外,药物转运体同样也起着举足轻重的作用。除他汀类、沙坦类等心血管系统化学药对转运体会产生影响外,近年来的研究表明,一些常用于治疗心血管系统疾病的中药组分亦会影响转运体的摄取外排功能,在与西药联合应用的过程中,可能会对介导西药的肝脏转运体产生影响,从而引起药动学改变而增加药品不良反应的发生。本文从治疗心血管系统疾病的常用中药组分对转运体的影响和与其他药物联用时可能发生的药物相互作用进行介绍,为临床提高药物治疗的有效性和安全性提供依据。 展开更多
关键词 中药 组分 转运体 调节
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An in vitro study on interaction of anisodine and monocrotaline with organic cation transporters of the SLC22 and SLC47 families
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作者 CHEN Jia-Yin Jürgen Brockmoller +2 位作者 Mladen V.Tzvetkov WANG Li-Jun CHEN Xi-Jing 《中国天然药物:英文版》 SCIE CAS CSCD 2019年第7期490-497,共8页
Current study systematically investigated the interaction of two alkaloids, anisodine and monocrotaline, with organic cation transporter OCT1, 2, 3, MATE1 and MATE2-K by using in vitro stably transfected HEK293 cells.... Current study systematically investigated the interaction of two alkaloids, anisodine and monocrotaline, with organic cation transporter OCT1, 2, 3, MATE1 and MATE2-K by using in vitro stably transfected HEK293 cells. Both anisodine and monocrotaline inhibited the OCTs and MATE transporters. The lowest IC50 was 12.9 μmol·L-1 of anisodine on OCT1 and the highest was 1.8 mmol·L-1 of monocrotaline on OCT2. Anisodine was a substrate of OCT2(Km = 13.3 ± 2.6 μmol·L-1 and Vmax = 286.8 ± 53.6 pmol/mg protein/min). Monocrotaline was determined to be a substrate of both OCT1(Km = 109.1 ± 17.8 μmol·L^-1, Vmax = 576.5 ± 87.5 pmol/mg protein/min) and OCT2(Km = 64.7 ± 14.8 μmol·L^-1, Vmax = 180.7 ± 22.0 pmol/mg protein/min), other than OCT3 and MATE transporters. The results indicated that OCT2 may be important for renal elimination of anisodine and OCT1 was responsible for monocrotaline uptake into liver. However neither MATE1 nor MATE2-K could facilitate transcellular transport of anisodine and monocrotaline. Accumulation of these drugs in the organs with high OCT1 expression(liver) and OCT2 expression(kidney) may be expected. 展开更多
关键词 ANISODINE MONOCROTALINE Organic CATION TRANSPORTER OCT MATE
Effect of Taichong(LR 3) acupuncture in spontaneously hypertensive rats
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作者 Luo Xiaozhou Huang Jianting +1 位作者 Yu Juan Tang Chunzhi 《中医杂志:英文版》 SCIE CAS CSCD 2019年第1期74-80,共7页
OBJECTIVE: To evaluate the effects of Taichong(LR3) acupuncture points(acupoints) on the expression of glucose transporter protein 1(GLUT1) in the hypothalamus of spontaneously hypertensive rats(SHRs) as measured by c... OBJECTIVE: To evaluate the effects of Taichong(LR3) acupuncture points(acupoints) on the expression of glucose transporter protein 1(GLUT1) in the hypothalamus of spontaneously hypertensive rats(SHRs) as measured by combined positron emission tomography and computed tomography(PETCT).METHODS: Spontaneously hypertensive rats(SHR)were divided into model, Taichong(LR 3) acupuncture, and sham groups. Additionally, Tokyo Wistar rats were used as the control group. Changes in blood pressure were recorded in different groups of rats before and after the corresponding treatment. Hematoxylin and eosin(HE) staining was used to study basic morphological changes, and immunohistochemistry was used to determine GLUT1 expression in the hypothalamus. Further,PET-CT was utilized to elucidate the antihypertensive mechanism after acupuncture at the Taichong(LR 3) acupoints.RESULTS: PET-CT indicated activation of the hypothalamus. Measurement of blood pressure showed that acupuncture at the Taichong(LR 3) acupoints lowered blood pressure. HE staining did not show any significant pathological changes, although differences in cell number were observed. Immunohistochemical analysis indicated a GLUT1 downregulation in the SHRs of the Taichong(LR 3) acupuncture group after the treatment.CONCLUSION: Acupuncture at Taichong(LR 3) acupoints lowered blood pressure in SHRs, with possible mechanisms being changes in cell number and GLUT1 expression in the hypothalamus. 展开更多
关键词 Hypertension ACUPUNCTURE Point LR 3(Taichong) Positron emission TOMOGRAPHY computed TOMOGRAPHY Glucose transporter type 1 Rats inbred SHR
The zinc transporter Slc39a5 controls glucose sensing and insulin secretion in pancreatic β-cells via Sirt1- and Pgc-1α-mediated regulation of Glut2
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作者 Xinhui Wang Hong Gao +11 位作者 Wenhui Wu Enjun Xie Yingying Yu Xuyan He Jin Li Wanru Zheng Xudong Wang Xizhi Cao Zhuoxian Meng Ligong Chen Junxia Min Fudi Wang 《蛋白质与细胞:英文版》 SCIE CAS CSCD 2019年第6期436-449,共14页
Zinc levels are high in pancreatic β-cells, and zinc is involved in the synthesis, processing and secretion of insulin in these cells. However, precisely how cellular zinc homeostasis is regulated in pancreatic β-ce... Zinc levels are high in pancreatic β-cells, and zinc is involved in the synthesis, processing and secretion of insulin in these cells. However, precisely how cellular zinc homeostasis is regulated in pancreatic β-cells is poorly understood. By screening the expression of 14 Slc39a metal importer family member genes, we found that the zinc transporter Slc39a5 is significantly downregulated in pancreatic β-cells in diabetic db/db mice, obese ob/ob mice and high-fat diet-fed mice. Moreover,β-cell-specific Slc39a5 knockout mice have impaired insulin secretion. In addition, Slc39a5-deficient pancreatic islets have reduced glucose tolerance accompanied by reduced expression of Pgc-1α and its downstream target gene Glut2. The down-regulation of Glut2 in Slc39a5-deficient islets was rescued using agonists of Sirt1, Pgc-1α and Ppar-γ. At the mechanistic level, we found that Slc39a5-mediated zinc influx induces Glut2 expression via Sirt1-mediated Pgc-1α activation. These findings suggest that Slc39a5 may serve as a possible therapeutic target for diabetes-related conditions. 展开更多
关键词 ZINC ZINC TRANSPORTER PANCREATIC ISLETS β-cells insulin secretion
PMC(装卸料)系统运行分析 预览
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作者 胡万有 杨鹏 +1 位作者 杨发 吴海东 《科技视界》 2019年第6期74-76,共3页
我厂4台机组装卸料系统在换料运行过程中,RX(核岛)厂房与KX(燃料)厂房装卸料机、人桥吊车与转运装置不能顺畅衔接、协同高效运作,本文分析该系统运行情况分析,找出合理的方案进行改进,实现换料过程各设备交接零接口。
关键词 堆芯 乏池 装卸料机 人桥吊车 转运装置 快/慢区域
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Emerging transporter-targeted nanoparticulate drug delivery systems
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作者 Hongyan Su Yan Wang +4 位作者 Shuo Liu Yue Wang Qian Liu Guangxuan Liu Qin Chen 《药学学报:英文版》 CSCD 2019年第1期49-58,共10页
Transporter-targeted nanoparticulate drug delivery systems(nano-DDS) have emerged as promising nanoplatforms for efficient drug delivery. Recently, great progress in transporter-targeted strategies has been made, espe... Transporter-targeted nanoparticulate drug delivery systems(nano-DDS) have emerged as promising nanoplatforms for efficient drug delivery. Recently, great progress in transporter-targeted strategies has been made, especially with the rapid developments in nanotherapeutics. In this review, we outline the recent advances in transporter-targeted nano-DDS. First, the emerging transporter-targeted nano-DDS developed to facilitate oral drug delivery are reviewed. These include improvements in the oral absorption of protein and peptide drugs, facilitating the intravenous-to-oral switch in cancer chemotherapy. Secondly, the recent advances in transporter-assisted brain-targeting nano-DDS are discussed,focusing on the specific transporter-based targeting strategies. Recent developments in transportermediated tumor-targeting drug delivery are also discussed. Finally, the possible transport mechanisms involved in transporter-mediated endocytosis are highlighted, with special attention to the latest findings of the interactions between membrane transporters and nano-DDS. 展开更多
关键词 TRANSPORTER Nano-DDS ORAL delivery Brain-targeting TUMOR-TARGETING
循环5-羟色胺对胆汁酸稳态的影响 预览
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作者 秦红岩 左晓 武新安 《基础医学与临床》 CSCD 2019年第4期569-572,共4页
5-羟色胺(5-HT)是人体重要的神经递质和胃肠激素,中枢神经系统和外周循环中的5-HT分属于完全独立的系统,循环5-HT主要来源于肠道。循环5-HT对肝脏胆酸合成酶及外排转运体具有调控作用,并可通过调控回肠及肾脏胆酸转运体影响胆酸的肠-肝... 5-羟色胺(5-HT)是人体重要的神经递质和胃肠激素,中枢神经系统和外周循环中的5-HT分属于完全独立的系统,循环5-HT主要来源于肠道。循环5-HT对肝脏胆酸合成酶及外排转运体具有调控作用,并可通过调控回肠及肾脏胆酸转运体影响胆酸的肠-肝循环及肾排泄,说明外周5-HT对胆汁酸稳态具有调控作用。研究并阐明5-HT对胆酸稳态的影响及机制,可为胆汁酸紊乱性疾病的发病机制研究提供线索,并为其治疗靶点的发现提供依据。 展开更多
关键词 5-羟色胺 胆汁酸 合成酶 转运体 肠-肝循环
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Alleviation of arsenic toxicity by phosphate is associated with its regulation of detoxification,defense,and transport gene expression in barley 预览
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作者 Gerald Zvobgo Jonas Lwalaba Wa Lwalaba +4 位作者 Tichaona Sagonda James Mutemachani Mapodzeke Noor Muhammad Imran Haider Shamsi ZHANG Guo-ping 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第2期381-394,共14页
Arsenic(As) contamination in soils has posed a severe threat to safe crop production. The previous studies showed the antagonism between phosphorus(P) and As in plant growth and As uptake, while the mechanisms of alle... Arsenic(As) contamination in soils has posed a severe threat to safe crop production. The previous studies showed the antagonism between phosphorus(P) and As in plant growth and As uptake, while the mechanisms of alleviating As toxicity by P is not completely clear. Due to the limiting P condition, it is imperative to understand how low P addition can be used to suppress arsenate As(V) uptake and the subsequent mechanisms involved. Thus in this study we investigated the effect of P addition on As uptake, anti-oxidative enzyme activity, and anti-oxidant content, and the relative expression of transport, defense, and detoxification genes using two barley genotypes differing in As toxicity tolerance. P addition significantly reduced As concentration in plant tissues, and caused the great changes in activities of catalase and superoxide dismutase, glutathione content, and the relative expression of examined genes when the plants of the two barley genotypes were exposed to 100 μmol L–1 As, with ZDB160(As-tolerant) being much more affected than ZDB475(As-sensitive). The current results show that P addition can alleviate As toxicity by regulating the expression of As transport, defense, and detoxification genes to a greater extent in As tolerance of barley, suggesting the possibility of controlling As uptake and toxicity by applying low amount of P fertilizers in the As-contaminated soils. 展开更多
关键词 ARSENATE PHOSPHATE TRANSPORTER tolerance toxicity
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MicroRNAs contribute to ATP-binding cassette transporter- and autophagy-mediated chemoresistance in hepatocellular carcinoma 预览
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作者 María V Espelt María L Bacigalupo +1 位作者 Pablo Carabias María F Troncoso 《世界肝病学杂志:英文版(电子版)》 2019年第4期344-358,共15页
Hepatocellular carcinoma (HCC) has an elevated mortality rate, largely because of high recurrence and metastasis. Additionally, the main obstacle during treatment of HCC is that patients usually develop resistance to ... Hepatocellular carcinoma (HCC) has an elevated mortality rate, largely because of high recurrence and metastasis. Additionally, the main obstacle during treatment of HCC is that patients usually develop resistance to chemotherapy. Cancer drug resistance involves many different mechanisms, including alterations in drug metabolism and processing, impairment of the apoptotic machine, activation of cell survival signaling, decreased drug sensitivity and autophagy, among others. Nowadays, miRNAs are emerging as master regulators of normal physiology- and tumor-related gene expression. In HCC, aberrant expression of many miRNAs leads to chemoresistance. Herein, we particularly analyzed miRNA impact on HCC resistance to drug therapy. Certain miRNAs target ABC (ATP-binding cassette) transporter genes. As most of these miRNAs are downregulated in HCC, transporter levels increase and intracellular drug accumulation decrease, turning cells less sensitive to death. Others miRNAs target autophagy-related gene expression, inhibiting autophagy and acting as tumor suppressors. Nevertheless, due to its downregulation in HCC, these miRNAs do not inhibit autophagy or tumor growth and, resistance is favored. Concluding, modulation of ABC transporter and/or autophagy-related gene expression or function by miRNAs could be determinant for HCC cell survival under chemotherapeutic drug treatment. Undoubtedly, more insights on the biological processes, signaling pathways and/or molecular mechanisms regulated by miRNAs are needed. Anyway, miRNA-based therapy together with conventional chemotherapeutic drugs has a great future in cancer therapy. 展开更多
关键词 HEPATOCELLULAR carcinoma CHEMORESISTANCE ABC TRANSPORTER AUTOPHAGY miRNA
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孕期野百合碱暴露对大鼠胎盘的损伤作用及其代谢机制 预览
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作者 刘杰 杨晓静 +4 位作者 郑江 王艳清 向娥 汪晖 郭喻 《中国药物警戒》 2019年第2期65-70,80共7页
目的探讨孕期野百合碱(monocrotaline,MCT)暴露对胎盘的损伤作用及其发生机制。方法 Wistar孕鼠分为给药组和对照组,在妊娠第9天至20天(gestation day,GD)灌胃给予20mg·kg^-1 MCT,对照组给予等体积的溶剂处理。在GD20给药2h后麻醉... 目的探讨孕期野百合碱(monocrotaline,MCT)暴露对胎盘的损伤作用及其发生机制。方法 Wistar孕鼠分为给药组和对照组,在妊娠第9天至20天(gestation day,GD)灌胃给予20mg·kg^-1 MCT,对照组给予等体积的溶剂处理。在GD20给药2h后麻醉处死大鼠,并取母肝及胎盘。观察胎盘重量和形态学改变,分别检测母肝、胎盘中吡咯代谢产物与蛋白结合物(pyrrole-protein adducts,PPAs)的含量,同时检测母肝及胎盘细胞色素P450(cytochrome P450,CYP)3A的基础表达和MCT暴露后表达水平,并确定了胎盘有机阳离子转运体3(organic cation transporter 3,OCT3)和P-糖蛋白(P-glycoprotein,P-gp)的表达变化。结果与对照组相比,孕期MCT处理大鼠胎盘重量显著降低,并伴有胎盘形态结构的损伤。胎盘的CYP3A基础表达远低于母肝,但MCT暴露后,胎盘PPAs含量几乎与母肝一致。与对照组相比,MCT暴露组胎盘的CYP3A1和OCT3表达无显著变化,而P-gp的表达显著增加。结论孕期MCT暴露可造成胎盘损伤,母肝代谢产生的活性吡咯代谢产物可能是造成胎盘损伤的主要原因。 展开更多
关键词 野百合碱 胎盘 细胞色素P4503A 转运体
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矿井运输机PLC控制系统选型设计及应用研究 预览
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作者 乔惠军 《机械管理开发》 2019年第3期198-199,210共3页
简单介绍控制系统工作原理,进行PLC控制器选型,程序设计PLC控制系统元器件及匹配地址。工业实践表明,选择西门子S7-200作为PLC控制器控制给料理想,能够满足工业需求。说明PLC选型合理,可更好地控制矿井运输机稳定运行,减少差错率,提高... 简单介绍控制系统工作原理,进行PLC控制器选型,程序设计PLC控制系统元器件及匹配地址。工业实践表明,选择西门子S7-200作为PLC控制器控制给料理想,能够满足工业需求。说明PLC选型合理,可更好地控制矿井运输机稳定运行,减少差错率,提高给料控制能力。 展开更多
关键词 运输机 PLC控制器 自动化 选型设计
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TP1700型运梁车驱动系统同步控制设计与应用 预览
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作者 王磊 《机床与液压》 北大核心 2019年第15期139-144,共6页
TP1700型运梁车采用分体式4车独立驱动系统,针对其同步精度要求高的问题,进行了理论分析及仿真研究,提出了使用压力与转速信号的同步控制方法。基于液压传动系统的规律,将其简化成泵变量机构与泵控马达两部分。以某一车为基准信号,调节... TP1700型运梁车采用分体式4车独立驱动系统,针对其同步精度要求高的问题,进行了理论分析及仿真研究,提出了使用压力与转速信号的同步控制方法。基于液压传动系统的规律,将其简化成泵变量机构与泵控马达两部分。以某一车为基准信号,调节其余车泵的排量,根据系统结构特点,分别满足不同车之间压力同步或转速同步。利用AMESim软件对系统进行建模与仿真,通过与实测数据进行对比,验证了仿真模型的准确性和系统原理的正确性。仿真和实际使用结果表明,采用压力与转速信号的同步控制方法,能够有效保证系统的同步性。 展开更多
关键词 运梁车 独立驱动系统 高精度 同步 压力与转速
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