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Effects of altering the ratio of C16:0 and cis-9 C18:1 in rumen bypass fat on growth performance, lipid metabolism, intestinal barrier, cecal microbiota, and inflammation in fattening bulls
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作者 Haixin Bai Haosheng Zhang +3 位作者 Congwen Wang Modinat Tolani Lambo Yang Li Yonggen Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2156-2174,共19页
Background C16:0 and cis-9 C18:1 may have different effects on animal growth and health due to unique metabolism in vivo.This study was investigated to explore the different effects of altering the ratio of C16:0 and ... Background C16:0 and cis-9 C18:1 may have different effects on animal growth and health due to unique metabolism in vivo.This study was investigated to explore the different effects of altering the ratio of C16:0 and cis-9 C18:1 in fat supplements on growth performance,lipid metabolism,intestinal barrier,cecal microbiota,and inflammation in fattening bulls.Thirty finishing Angus bulls(626±69 kg,21±0.5 months)were divided into 3 treatments according to the randomized block design:(1)control diet without additional fat(CON),(2)CON+2.5%palmitic acid calcium salt(PA,90%C16:0),and(3)CON+2.5%mixed fatty acid calcium salt(MA,60%C16:0+30%cis-9 C18:1).The experiment lasted for 104 d,after which all the bulls were slaughtered and sampled for analysis.Results MA tended to reduce 0–52 d dry matter intake compared to PA(DMI,P=0.052).Compared with CON and MA,PA significantly increased 0–52 d average daily gain(ADG,P=0.027).PA tended to improve the 0–52 d feed conversion rate compared with CON(FCR,P=0.088).Both PA and MA had no significant effect on 52–104 days of DMI,ADG and FCR(P>0.05).PA tended to improve plasma triglycerides compared with MA(P=0.077),significantly increased plasma cholesterol(P=0.002)and tended to improve subcutaneous adipose weight(P=0.066)when compared with CON and MA.Both PA and MA increased visceral adipose weight compared with CON(P=0.021).Only PA increased the colonization of Rikenellaceae,Ruminococcus and Proteobacteria in the cecum,and MA increased Akkermansia abundance(P<0.05).Compared with CON,both PA and MA down-regulated the m RNA expression of Claudin-1 in the jejunum(P<0.001),increased plasma diamine oxidase(DAO,P<0.001)and lipopolysaccharide(LPS,P=0.045).Compared with CON and MA,PA down-regulated the ZO-1 in the jejunum(P<0.001)and increased plasma LPS-binding protein(LBP,P<0.001).Compared with CON,only PA down-regulated the Occludin in the jejunum(P=0.013).Compared with CON,PA and MA significantly up-regulated the expression of TLR-4 and NF-κB in the visceral adipose(P<0.001)and increased plasma IL-6(P<0.001).Compared with CON,only PA up-regulated the TNF-αin the visceral adipose(P=0.01).Compared with CON and MA,PA up-regulated IL-6 in the visceral adipose(P<0.001),increased plasma TNF-α(P<0.001),and reduced the Ig G content in plasma(P=0.035).Compared with CON,PA and MA increased C16:0 in subcutaneous fat and longissimus dorsi muscle(P<0.05),while more C16:0 was also deposited by extension and desaturation into C18:0 and cis-9 C18:1.However,neither PA nor MA affected the content of cis-9 C18:1 in longissimus dorsi muscle compared with CON(P>0.05).Conclusions MA containing 30%cis-9 C18:1 reduced the risk of high C16:0 dietary fat induced subcutaneous fat obesity,adipose tissue and systemic low-grade inflammation by accelerating fatty acid oxidative utilization,improving colonization of Akkermansia,reducing intestinal barrier damage,and down-regulating NF-κB activation. 展开更多
关键词 C16:0 cis-9 C18:1 Finishing bulls Intestinal homeostasis Lipid metabolism Low-grade inflammation
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Properties of high cis-1,4 content hydroxyl-terminated polybutadiene and its application in composite solid propellants
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作者 Deqian Meng Lipeng Sang +2 位作者 Pingan Zhang Jianru Deng Xiang Guo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期199-209,共11页
In this paper,high cis-1,4 content hydroxyl-terminated polybutadiene(cis-HTPB)with different molecular weights was prepared through the oxidative cracking process using cis-butadiene rubber as raw material.Firstly,thi... In this paper,high cis-1,4 content hydroxyl-terminated polybutadiene(cis-HTPB)with different molecular weights was prepared through the oxidative cracking process using cis-butadiene rubber as raw material.Firstly,this article comprehensively compared the differences between cis-HTPB and conventional I-HTPB in terms of molecular weight distribution,functionality,viscosity,molecular polarity,and other physicochemical properties,which provided effective data support for its subsequent application.In addition,the reaction kinetics study showed that cis-HTPB with isocyanate curing agent has high reactivity,allowing it to be rapidly cured at low temperatures,and the cured elastomers had excellent mechanical properties,with tensile strength and elongation up to 1.89 MPa and 1100%,respectively.It was also found that cis-HTPB has extremely excellent low-temperature resistance,and the glass transition temperature(T_(g))of its cured elastomer is as low as-101℃.Based on the above studies,cis-HTPB is applied as a binder in composite solid propellants for the first time to investigate its practical performance,and the results indicated that cis-HTPB-based propellants have excellent process and mechanical properties. 展开更多
关键词 High cis-1 4 content-HTPB(cis-HTPB) Low-temperature resistance Comparison of physicochemical properties cis-HTPB curing process cis-HTPB based propellant
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茶叶和土壤中cis-联苯菊酯、高效氯氟氰菊酯手性对映体残留分析 被引量:1
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作者 宁亚婷 王新茹 +2 位作者 罗逢健 李建勋 张新忠 《核农学报》 CAS CSCD 北大核心 2023年第11期2243-2251,共9页
为了满足茶叶和土壤中手性农药cis-联苯菊酯和高效氯氟氰菊酯对映异构体残留检测的需要,本试验首次对比研究了正相液相色谱条件下,Daicel ChiralPak®AS-H、Phenomenex®Cellulose-1和Cellulose-3柱对两组手性对映体的拆分效果... 为了满足茶叶和土壤中手性农药cis-联苯菊酯和高效氯氟氰菊酯对映异构体残留检测的需要,本试验首次对比研究了正相液相色谱条件下,Daicel ChiralPak®AS-H、Phenomenex®Cellulose-1和Cellulose-3柱对两组手性对映体的拆分效果,以及气相色谱条件下BGB-172柱的分离测定效果,并建立了基于手性气相色谱分离的茶叶和土壤中cis-联苯菊酯和高效氯氟氰菊酯对映体残留分析方法。样品采用正己烷和丙酮提取,Florisil与GCB混合柱净化,气相色谱手性柱BGB-172程序升温分离,电子捕获检测器(ECD)外标法定性定量测定。结果表明,在2.5~800μg·L^(-1)浓度范围内,cis-联苯菊酯对映体色谱峰面积(Y)与浓度(x)之间分别满足线性方程Y=15381.1x-279657.5(r=0.9967)和Y=17387.6x-399048.0(r=0.9937),对映体分数(EF值)=0.489±0.017;在2.5~200μg·L^(-1)浓度范围内,高效氯氟氰菊酯对映体分别满足线性方程Y=22083.8x-161004.3(r=0.9923)和Y=23001.1x-167694.8(r=0.9922),EF=0.492±0.008。在0.005、0.050和0.50 mg·kg^(-1)3个添加浓度水平下,cis-联苯菊酯和高效氯氟氰菊酯对映体在不同茶叶、土壤样品中的平均添加回收率为61.6%~123.4%,相对标准偏差(RSD)为2.5%~14.6%,检测限低于0.001 mg·L^(-1),方法定量限低于0.005 mg·kg^(-1),不同样品中未见到明显基质效应。综上,该方法能够满足cis-联苯菊酯和高效氯氟氰菊酯对映体残留分析的需要,用于研究茶鲜叶中cis-联苯菊酯和高效氯氟氰菊酯对映体残留消解,且无明显对映体选择性差异。本研究结果为进一步开展2种手性农药在茶叶生长和加工过程中的残留和消解规律研究提供了技术支持。 展开更多
关键词 茶叶和土壤 cis-联苯菊酯 高效氯氟氰菊酯 对映异构体 残留分析
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新型消毒副产物 cis-2-丁烯-1,4-二醛的检测方法建立与评估
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作者 李俊芳 华哲超 +2 位作者 周志洪 黄雄飞 方晶云 《环境化学》 CAS CSCD 北大核心 2023年第4期1148-1155,共8页
饮用水消毒对病原微生物的预防起到至关重要的作用,但是有毒有害消毒副产物的产生,对人类健康造成潜在威胁.cis-2-丁烯-1,4-二醛(BDA)是近年检出的新型消毒副产物,生物毒性强,具有严重的潜在危害.本文建立了BDA的高效液相色谱-串联质谱... 饮用水消毒对病原微生物的预防起到至关重要的作用,但是有毒有害消毒副产物的产生,对人类健康造成潜在威胁.cis-2-丁烯-1,4-二醛(BDA)是近年检出的新型消毒副产物,生物毒性强,具有严重的潜在危害.本文建立了BDA的高效液相色谱-串联质谱的分析方法,旨在定量筛查出水体中的BDA.结果表明:BDA的纯溶剂标准曲线和基质匹配标准曲线的线性较好,相关系数(R^(2))均大于0.99.方法检出限为0.035μmol·L^(−1),定量限值为0.105μmol·L^(−1).回收率在83.6%‒112%之间,相对标准偏差小于10%(n=7).该方法能够快速高效地完成水体中BDA的分析. 展开更多
关键词 消毒 消毒副产物 cis-2-丁烯-1 4-二醛 高效液相色谱-串联质谱 (HPLC-MS/MS) N-乙酰基赖 氨酸衍生
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毛细管气相色谱法测定乳脂中的cis-9,trans-11-共轭亚油酸 被引量:18
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作者 王小静 沈向真 +2 位作者 韩航如 赵茹茜 陈杰 《色谱》 CAS CSCD 北大核心 2006年第6期645-647,共3页
建立了测定乳脂中cis-9,trans-11-共轭亚油酸(CLA)的毛细管气相色谱方法。样品经正己烷-异丙醇提取、甲醇-甲醇钠甲酯化后,进行气相色谱分析;采用程序升温,以保留时间定性,外标法定量。采用该方法测得共轭亚油酸的回收率为100.26%,相对... 建立了测定乳脂中cis-9,trans-11-共轭亚油酸(CLA)的毛细管气相色谱方法。样品经正己烷-异丙醇提取、甲醇-甲醇钠甲酯化后,进行气相色谱分析;采用程序升温,以保留时间定性,外标法定量。采用该方法测得共轭亚油酸的回收率为100.26%,相对标准偏差(RSD)为1.9%(n=6),检测限为1 mg/L。该方法样品用量少,前处理简单,建立的实验条件准确可靠,不仅可以用来测定cis-9,trans-11-CLA的含量,而且对于乳制品中所含的其他脂肪酸的分析测定也具有指导意义。 展开更多
关键词 毛细管气相色谱法 cis-9 trans-11-其轭业油酸 乳脂
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266nm脉冲激光光解基质隔离的cis-(NO)_2
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作者 王雪峰 余敏 秦启宗 《物理化学学报》 SCIE CAS CSCD 北大核心 1996年第8期673-676,共4页
The photodissociation of cis-(NO)2 in N2 and Ar matrices under 266 nm pulsed laser irradiation is reported- Results show the electronically excited o(1D) atom may be formed in the primary photolysis step. In the N2 ma... The photodissociation of cis-(NO)2 in N2 and Ar matrices under 266 nm pulsed laser irradiation is reported- Results show the electronically excited o(1D) atom may be formed in the primary photolysis step. In the N2 matrix, the highly active o(1D) atoms could either react with N2 lattice molecules forming N2O or recombine with nearby N2O forming cis-(NO)2 and trans-(NO)2. However, in the Ar matrix the nascent state o(1D) atom, due to the lack of reactant, quenches to O(3P) as moving through the lattice site and the yield of N2O is less than that in N2 matrix. 展开更多
关键词 基质隔离 激光光解 cis-(NO)2 脉冲
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cis-丙环唑的制备及其晶体结构的研究
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作者 罗金香 杨春龙 《农药学学报》 CAS CSCD 2006年第1期20-24,共5页
采用丙环唑与硝酸成盐法和硅胶柱层析法制备了cis-丙环唑,并培养出单晶,用X射线单晶衍射法确定了其立体结构。晶体属单斜晶系,P21/c空间群,晶胞参数a=1.065 3(3)nm,b=1.894 0(6)nm,c=0.810 4(3)nm,β=100.032(6),°Z=4,V=1.610 0(9)... 采用丙环唑与硝酸成盐法和硅胶柱层析法制备了cis-丙环唑,并培养出单晶,用X射线单晶衍射法确定了其立体结构。晶体属单斜晶系,P21/c空间群,晶胞参数a=1.065 3(3)nm,b=1.894 0(6)nm,c=0.810 4(3)nm,β=100.032(6),°Z=4,V=1.610 0(9)nm3,Dc=1.412g/cm3,F(000)=712,u=0.413mm-1,R=0.066 2,wR=0.136 9。 展开更多
关键词 cis-丙环唑 制备 晶体结构
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13-cis-维A酰衍生物合成方法的改进
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作者 易卫国 刘志常 +3 位作者 向莉 刘西洋 陈静 向建南 《应用化学》 CAS CSCD 北大核心 2007年第5期521-524,共4页
改进并建立了以4-二甲氨基吡啶(DMAP)-对甲苯磺酸盐为催化剂,二环己基碳酰亚胺(DCC)为缩合剂直接用13-cis-维A酸与醇、酚或胺合成13-cis-维A酰衍生物的方法。合成了8种新目标化合物,收率80%~95%,核磁共振氢谱和碳谱研究表明,13-cis-维... 改进并建立了以4-二甲氨基吡啶(DMAP)-对甲苯磺酸盐为催化剂,二环己基碳酰亚胺(DCC)为缩合剂直接用13-cis-维A酸与醇、酚或胺合成13-cis-维A酰衍生物的方法。合成了8种新目标化合物,收率80%~95%,核磁共振氢谱和碳谱研究表明,13-cis-维A酰部分的构型均保持不变。合成方法彻底抑制了反应中N-异维A酰基脲的副反应,而且反应条件温和,对于极易异构化的13c-is-维A酸的酯化和酰胺化反应十分有利。 展开更多
关键词 药物化学 方法改进 异维A酰化 cis-维A酸衍生物 二环己基碳酰亚胺
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“trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物水解反应动力学常数测定”实验教学实施结果与探讨
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作者 张春艳 欧阳小清 +8 位作者 阮婵姿 吕银云 潘蕊 翁玉华 董志强 许振玲 彭淑女 李华敏 任艳平 《大学化学》 CAS 2021年第8期155-163,共9页
主要介绍厦门大学专门为"化学拔尖计划"学生个性化培养"量身定制"并经10年教学实践的"trans/cis-[Co(en)2Cl2]Cl配合物水解反应动力学常数测定"实验教学实施结果及探讨内容。引导学生以动力学实验数据和... 主要介绍厦门大学专门为"化学拔尖计划"学生个性化培养"量身定制"并经10年教学实践的"trans/cis-[Co(en)2Cl2]Cl配合物水解反应动力学常数测定"实验教学实施结果及探讨内容。引导学生以动力学实验数据和实验结果为依据,讨论和探究了介质、温度等对trans/cis-[Co(en)2Cl2]Cl配合物水解反应的影响,让学生直观认识顺-反异构体配合物的结构不同,所表现的水解反应动力学的差异,了解结构决定性质的涵义,培养学生归纳、总结、分析、判断的能力以及批判性思维能力。 展开更多
关键词 trans/cis-[Co(en)_(2)Cl_(2)]Cl 水解反应动力学 实验结果分析与探讨
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“trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物的制备及其光谱鉴定”实验教学实施结果与探讨——培养学生批判性思维的典型案例之一
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作者 欧阳小清 张春艳 +8 位作者 潘蕊 阮婵姿 吕银云 翁玉华 董志强 彭淑女 李华敏 许振玲 任艳平 《大学化学》 CAS 2021年第3期79-86,共8页
主要介绍厦门大学专门为"化学拔尖计划"学生个性化培养"量身定制"的"trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物的制备及其光谱鉴定"实验教学实施结果及探讨。以"trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物... 主要介绍厦门大学专门为"化学拔尖计划"学生个性化培养"量身定制"的"trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物的制备及其光谱鉴定"实验教学实施结果及探讨。以"trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物的制备及其光谱鉴定"实验为载体,围绕着合成两大目标"质"和"量",也就是以如何才能得到又"好"又"多"的trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物等问题为导向,以所展示的详细直观的制备流程和紫外-可见吸收光谱图为基础,以实验结果为依据,以设问、探讨的方式对合成过程、条件等进行仔细分析和深刻反思、判断,以展示实验教学过程中如何有效地培养学生的批判性思维。 展开更多
关键词 trans/cis-[Co(en)_(2)Cl_(2)]Cl 制备与鉴定 实验结果分析与探讨 翻转课堂 批判性思维
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Cis-4-甲氧基环己基-1-氨基甲酸甲酯的合成工艺改进
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作者 何晓明 付炎 +1 位作者 党云洁 罗啸 《煤炭与化工》 CAS 2017年第2期53-56,共4页
以对甲氧基苯酚固定床催化加氢法一步合成对甲氧基环己酮,再经过Bucherer-bergs成环、水解、酯化合成Cis-4-甲氧基环己基-1-氨基甲酸甲酯,反应总收率为28.0%。此方法减少了反应步骤,操作更简单,解决了催化剂分离的问题,同时也节省了生... 以对甲氧基苯酚固定床催化加氢法一步合成对甲氧基环己酮,再经过Bucherer-bergs成环、水解、酯化合成Cis-4-甲氧基环己基-1-氨基甲酸甲酯,反应总收率为28.0%。此方法减少了反应步骤,操作更简单,解决了催化剂分离的问题,同时也节省了生产成本,适于工业化生产。 展开更多
关键词 螺虫乙酯 催化加氢法 对甲氧基环己酮 cis-4-甲氧基环己基-1-氨基甲酸甲酯 固定床
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低温预制钛系催化剂合成cis-1,4-聚异戊二烯 被引量:2
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作者 汪昭玮 于俊伟 +1 位作者 李兴 刘晓暄 《化工学报》 EI CAS CSCD 北大核心 2015年第7期2521-2527,共7页
采用Ziegler-Natta配位聚合制备了高顺式聚异戊二烯,主要考察了非均相催化体系四氯化钛-三异丁基铝二组分催化剂的预制方法以及催化剂预制条件对异戊二烯体系聚合规律的影响。讨论了催化剂配比、预制催化剂温度和陈化温度对催化剂活性... 采用Ziegler-Natta配位聚合制备了高顺式聚异戊二烯,主要考察了非均相催化体系四氯化钛-三异丁基铝二组分催化剂的预制方法以及催化剂预制条件对异戊二烯体系聚合规律的影响。讨论了催化剂配比、预制催化剂温度和陈化温度对催化剂活性及聚合物的凝胶含量、特征黏度、微观结构含量等方面的影响。同时讨论了催化剂用量、聚合温度和聚合时间对聚合活性及聚合物的凝胶含量、特征黏度、微观含量等方面的影响。研究结果表明,合成高cis-1,4-聚异戊二烯的最佳实验条件为:Al/Ti摩尔比1.0,催化剂预制温度-40℃,陈化2 h,Ti/Ip摩尔比6×10-3,聚合温度50℃,聚合时间5 h。所得聚合物最高转化率为87.1%,cis-1,4结构含量为91.76%。 展开更多
关键词 催化剂 配位聚合 cis-1 4-聚异戊二烯 低温 多相反应 活性
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新型N-[cis-3-(2-氯-3,3,3-三氟丙烯基)-2,2-二甲基环丙烷基羰基]-N'-芳氧乙酰肼的合成与生物活性 被引量:1
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作者 蒙柳 石德清 《有机化学》 SCIE CAS CSCD 北大核心 2009年第7期1100-1104,共5页
为了寻找高效、低毒的农药先导化合物,利用cis-3-(2-氯-3,3,3-三氟丙烯基)-2,2-二甲基环丙烷酰氯(1)与芳氧乙酰肼的缩合反应,合成了12种未见文献报道的目标化合物,其结构经IR,1HNMR,MS和元素分析测试技术确证.初步的生物活性测定结果表... 为了寻找高效、低毒的农药先导化合物,利用cis-3-(2-氯-3,3,3-三氟丙烯基)-2,2-二甲基环丙烷酰氯(1)与芳氧乙酰肼的缩合反应,合成了12种未见文献报道的目标化合物,其结构经IR,1HNMR,MS和元素分析测试技术确证.初步的生物活性测定结果表明,部分目标化合物在100mg/L浓度下对双子叶植物(油菜)显示出良好的除草活性;同时,部分化合物在200mg/L浓度下对蚕豆蚜虫(Aphisfabae)显示出较好的杀虫活性。 展开更多
关键词 cis-3-(2-氯-3 3 3-三氟丙烯基)-2 2-二甲基环丙烷羧酸 芳氧乙酸 双酰肼 生物活性
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Effect of apoptosis on gastric adenocarcinoma cell line SGC-7901 induced by cis-9,trans-11-conjugated linoleic acid 被引量:20
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作者 Jia-RenLiu Bing-QingChen +2 位作者 Yan-MeiYang Xuan-LingWang Ying-BenXue 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第6期999-1004,共6页
AIM: To determine the effect of apoptosis on gastric cancer cells (SGC-7901) induced by cis-9, trans-11-conjugated linoleic acid (c9, t11-CLA) and its possible mechanism in the inhibition of cancer cells growth.METHOD... AIM: To determine the effect of apoptosis on gastric cancer cells (SGC-7901) induced by cis-9, trans-11-conjugated linoleic acid (c9, t11-CLA) and its possible mechanism in the inhibition of cancer cells growth.METHODS: Using cell culture, flow cytometery and immunocytochemical techniques, we examined the cell growth, frequency of apoptosis and distribution of cell cycle,expression of ki67, bcl-2, Fas, and c-myc of SGC-7901 cells which were treated with various c9, t11-CLA concentrations (25,50,100 and 200 μmol@L-1) of c9, t11-CLA for 24h and 48 h,with a negative control (0.1% ethanol).RESULTS: The growth of SGC-7901 cells was inhibited by c9,t11-CLA. Eight days after treatment with various concentrations of c9,t11-CLA, as mentioned above, the inhibition rates were 5.9 %, 20.2 %,75.6 % and 82.4 %, respectively. The frequency of apoptosis on SGC-7901 cells induced by different concentrations of c9, t11-CLA (except for 25 μmol@L-1, 24 h) was significantly greater than that in the negative control (P<0.01). To further investigate the influence of the cell cycle progression, we found that apoptosis induced by c9, t11-CLA may be involved in blocking the cell cycle of SGC-7901 cells. Immunocytochemical staining demonstrated that SGC-7901 cells preincubated in media supplemented with different c9, t11-CLA concentrations for various time periods significantly decreased the expressions of ki67 (the expression rates were 18.70-3.20 %, at 24 h and 8.10-0.20 % at 48 h, respectively), bd-2 (4.30-0.15 % at 24 h and 8.05 %-0 at 48 h),and c-myc(4.85-2.20 % at 24 h and 4.75-0.30 % at 48 h) as compared with those in the controls (the expressions of ki67, bcl-2, and c-mycwere 15.1% at 24 h and 13.5 % at 48 h, 6.80 % at 24 h and 8.00 % at 48 h,5.50 % at 24 h and 5.30 % at 48 h, respectively) (P<0.01),whereas the expressions of Fas were increased (0.60-2.75 %,24 h and 0.45-5.95 %, 48 h).CONCLUSION: The growth and proliferation of SGC-7901 cells are inhibited by cg, t11-CLA via blocking the cell cycle,pathways of bcl-2-associated mitochondria with reduced expression of bcl-2 and Fas-associated death domain protein (FADD) with enhanced expression of Fas. But expression of c-myc on SGC-7901 cells is lower than that in negative control, which needs to be studied further. 展开更多
关键词 胃腺癌细胞系 SGC-7901 亚麻酸衍生物 cis-9 trans-11 诱发凋亡
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A HIGHLY ACTIVE NEODYMIUM CHLORIDE ISOPROPANOL COMPLEX/MODIFIED METHYLALUMINOXANE CATALYST FOR PREPARING POLYISOPRENE WITH HIGH CIS-1,4 STEREOSPECIFICITY AND NARROW MOLECULAR WEIGHT DISTRIBUTION 被引量:5
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作者 董伟民 张学全 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第2期157-164,共8页
Neodymium chloride isopropanol complex (NdCl3.3'prOH) activated by modified methylaluminoxane (MMAO) was examined in isoprene polymerization in hexane, with regards to Nd compounds, aluminum (Al) compounds, [Al... Neodymium chloride isopropanol complex (NdCl3.3'prOH) activated by modified methylaluminoxane (MMAO) was examined in isoprene polymerization in hexane, with regards to Nd compounds, aluminum (Al) compounds, [Al]/[Nd] ratio, polymerization temperature and time. NdCl3'3iprOH exhibited high activity producing polymers feasting high cis-l,4 stereospecificity (〉 96%), very high molecular weight (Mn 〉 1.0 × 10^6) and fairly narrow molecular weight distribution (MWD, Mw/Mn 〈 2.0) simultaneously. In comparison, neodymium isopropoxide also showed high activity providing polymers with narrow MWD (Mw/Mn = 2.07), but somewhat low cis-1,4 content (ca. 92%), while neodymium chloride had no activity under present polymerization conditions. The Al compounds affected the polymer yield in the order of Al(i-Bu)3 〉 MMAO 〉 Al(i-Bu)2H. MMAO as cocatalyst afforded polyisoprene with high Mn over 1.0 × 10^6, whereas as stronger chain transfer agent than MMAO, AI(i-Bu)3 and AI(i-Bu)EH yielded polymers with low Mn (1.0 × 10^5-8.0 × 10^5). NdCl3·3'PrOH/MMAO catalyst showed a fairly good catalytic activity even at relatively low [Al]/[Nd] ratio of 30, and the produced polymer remained high cis-1,4 content of 95.8% along with high Mn over 1.0× 10^6 even at elevated temperatures up to 70℃. The polymerization rate is of the first order with respect to the concentration of isoprene. The mechanism of active species formation was discussed preliminarily. 展开更多
关键词 ISOPRENE NEODYMIUM Molecular weight distribution cis-1 4 stereospecificity Ziegler-Natta polymerization.
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High rumen degradable starch decreased goat milk fat via trans-10,cis-12 conjugated linoleic acid-mediated downregulation of lipogenesis genes,particularly,INSIG1 被引量:5
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作者 Lixin Zheng Shengru Wu +6 位作者 Jing Shen Xiaoying Han Chunjia Jin Xiaodong Chen Shengguo Zhao Yangchun Cao Junhu Yao 《Journal of Animal Science and Biotechnology》 CAS CSCD 2020年第3期805-818,共14页
Background:Starch is an important substance that supplies energy to ruminants.To provide sufficient energy for high-yielding dairy ruminants,they are typically fed starch-enriched diets.However,starch-enriched diets h... Background:Starch is an important substance that supplies energy to ruminants.To provide sufficient energy for high-yielding dairy ruminants,they are typically fed starch-enriched diets.However,starch-enriched diets have been proven to increase the risk of milk fat depression(MFD)in dairy cows.The starch present in ruminant diets could be divided into rumen-degradable starch(RDS)and rumen escaped starch(RES)according to their different degradation sites(rumen or intestine).Goats and cows have different sensitivities to MFD.Data regarding the potential roles of RDS in milk fat synthesis in the mammary tissue of dairy goats and in regulating the occurrence of MFD are limited.Results:Eighteen Guanzhong dairy goats(day in milk=185±12 d)with similar parity,weight,and milk yield were selected and randomly assigned to one of three groups(n=6),which were fed an LRDS diet(Low RDS=20.52%),MRDS diet(Medium RDS=22.15%),or HRDS diet(High RDS=24.88%)for 5 weeks.Compared with that of the LRDS group,the milk fat contents in the MRDS and HRDS groups significantly decreased.The yields of short-,mediumand long-chain fatty acids decreased in the HRDS group.Furthermore,increased RDS significantly decreased ruminal B.fibrisolvens and Pseudobutyrivibrio abundances and increased the trans-10,cis-12 conjugated linoleic acid(CLA)and trans-10 C18:1 contents in the rumen fluid.A multiomics study revealed that the HRDS diet affected mammary lipid metabolism down-regulation of ACSS2,MVD,AGPS,SCD5,FADS2,CERCAM,SC5D,HSD17B7,HSD17B12,ATM,TP53RK,GDF1 and LOC102177400.Remarkably,the significant decrease of INSIG1,whose expression was depressed by trans-10,cis-12 CLA,could reduce the activity of SREBP and,consequently,downregulate the downstream gene expression of SREBF1.Conclusions:HRDS-induced goat MFD resulted from the downregulation of genes involved in lipogenesis,particularly,INSIG1.Specifically,even though the total starch content and the concentrate-to-fiber ratio were the same as those of the high-RDS diet,the low and medium RDS diets did not cause MFD in lactating goats. 展开更多
关键词 Dairy goat INSIG1 Milk fat depression Rumen degradable starch Trans-10 cis-12 CLA
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Cis-2-dodecenoic Acid Mediates Its Synergistic Effect with Triazoles by Interfering with Efflux Pumps in Fluconazole-resistant Candida albicans 被引量:3
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作者 YANG Dong Liang HU Yan Ling +7 位作者 YIN Zi Xin ZENG Gui Sheng LI Dan ZHANG Yu Qian XU Zhen Hua GUAN Xiao Ming WENG Li Xing WANG Lian Hui 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2019年第3期199-209,共11页
Objective To evaluate the synergy of the Burkholderia signaling molecule cis-2-dodecenoic acid(BDSF) and fluconazole(FLU) or itraconazole(ITRA) against two azole-resistant C. albicans clinical isolates in vitro and in... Objective To evaluate the synergy of the Burkholderia signaling molecule cis-2-dodecenoic acid(BDSF) and fluconazole(FLU) or itraconazole(ITRA) against two azole-resistant C. albicans clinical isolates in vitro and in vivo. Methods Minimum inhibitory concentrations(MICs) of antibiotics against two azole-resistant C. albicans were measured by the checkerboard technique, E-test, and time-kill assay. In vivo antifungal synergy testing was performed on mice. Analysis of the relative gene expression levels of the strains was conducted by quantitative reverse-transcription polymerase chain reaction(qR T-PCR). Results BDSF showed highly synergistic effects in combination with FLU or ITRA with a fractional inhibitory concentration index of ≤ 0.08. BDSF was not cytotoxic to normal human foreskin fibroblast cells at concentrations of up to 300 μg/mL. The qR T-PCR results showed that the combination of BDSF and FLU/ITRA significantly inhibits the expression of the efflux pump genes CDR1 and MDR1 via suppression of the transcription factors TAC1 and MRR1, respectively, when compared with FLU or ITRA alone. No dramatic difference in the mR NA expression levels of ERG1, ERG11, and UPC2 was found, which indicates that the drug combinations do not significantly interfere with UPC2-mediated ergosterol levels. In vivo experiments revealed that combination therapy can be an effective therapeutic approach to treat candidiasis. Conclusion The synergistic effects of BDSF and azoles may be useful as an alternative approach to control azole-resistant Candida infections. 展开更多
关键词 C. ALBICANS cis-2-dodecenoic acid azole-resistant Combination MDR1 CDR1
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Protective Effects of cis-2-Dodecenoic Acid in an Experimental Mouse Model of Vaginal Candidiasis 被引量:1
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作者 YANG Dong Liang ZHANG Yu Qian +3 位作者 HU Yan Ling WENG Li Xing ZENG Gui Sheng WANG Lian Hui 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第11期816-828,共13页
Objective To evaluate the efficacy of cis-2-dodecenoic acid(BDSF) in the treatment and prevention of vaginal candidiasis in vivo. Methods The activities of different concentrations of BDSF against the virulence factor... Objective To evaluate the efficacy of cis-2-dodecenoic acid(BDSF) in the treatment and prevention of vaginal candidiasis in vivo. Methods The activities of different concentrations of BDSF against the virulence factors of Candida albicans(C. albicans) were determined in vitro. An experimental mouse model of Candida vaginitis was treated with 250 μmol/L BDSF. Treatment efficiency was evaluated in accordance with vaginal fungal burden and inflammation symptoms. Results In vitro experiments indicated that BDSF attenuated the adhesion and damage of C. albicans to epithelial cells by decreasing phospholipase secretion and blocking filament formation. Treatment with 30 μmol/L BDSF reduced the adhesion and damage of C. albicans to epithelial cells by 36.9% and 42.3%, respectively. Treatment with 200 μmol/L BDSF completely inhibited phospholipase activity. In vivo mouse experiments demonstrated that BDSF could effectively eliminate vaginal infection and relieve inflammatory symptoms. Four days of treatment with 250 μmol/L BDSF reduced vaginal fungal loads by 6-fold and depressed inflammation. Moreover, BDSF treatment decreased the expression levels of the inflammatory chemokine-associated genes MCP-1 and IGFBP3 by 2.5-and 2-fold, respectively. Conclusion BDSF is a novel alternative drug that can efficiently control vaginal candidiasis by inhibiting the virulence factors of C. albicans. 展开更多
关键词 C.albicans cis-2-dodecenoic acid Virulence factor CANDIDIASIS
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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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Cis-and Trans-Coordination Assembly of Nitrogen Heterocycle with Copper(Ⅱ) and Silver(Ⅰ)
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作者 TAN Di TAN Gui-ping +3 位作者 HUANG Xiao-chun TONG Shan-ling YANG Ke-er YAN Yan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第6期661-667,共7页
After the preparation of 1,4-bis(4,5-dihydro-lH-imidazol-2-yl)benzene(bdib), a nitrogen heterocycle with potential coordination manners of both cis- and trans-configuration forms, three complexes, including cis-[... After the preparation of 1,4-bis(4,5-dihydro-lH-imidazol-2-yl)benzene(bdib), a nitrogen heterocycle with potential coordination manners of both cis- and trans-configuration forms, three complexes, including cis-[Cuz(bdib )2(/L-OCH3)2]Cl2·2MeOH(1), trans-[Cu(bdib)(AcO)2]n(2), and cis-[Ag2(bdib)2](NO3)2.2H20(3), were successfully self-assembled. Complexes 1 and 2 crystallized in the monoclinic system with P21/n space group and complex 3 in the triclinic system with P1 space group. 展开更多
关键词 Nitrogen heterocycle cis- and trans-coordination COPPER SILVER
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