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为探讨不同浓度的绿萝花制剂对线粒体的抗氧化作用及毒理作用,以小鼠胚胎成纤维细胞及其线粒体为研究对象,在最大无毒作用浓度(TC_0)的基础上设计3个浓度药物组,在TC_0下设计6个浓度药物组,以成纤维细胞线粒体膜电位(MMP)和线粒体总活性氧含量(ROS)为检测指标,在4个不同作用时间点,研究绿萝花对成纤维细胞线粒体的影响。结果表明,绿萝花制剂对鼠胚成纤维细胞(MEF)的TC_0为0.25g/mL,但ROS已急剧上升,MMP下降;绿萝花浓度为0.03g/mL时,抗氧化能力最强,随着浓度的上升(0.03g/mL~0.25g/mL),线粒体抗氧化能力减弱或消失;随着给药浓度的升高,细胞凋亡现象出现趋势明显,浓度高于TC_0时,表现出毒性作用,浓度升高,毒性增大。绿萝花干膏制剂0.03g/mL(以生药含量计算)具有抵抗由H_2O_2引起的MEF线粒体MMP下降和ROS的升高的功能,表现出一定的抗氧化能力和阻滞细胞凋亡发生的作用;TC_0及之上浓度具有细胞毒性作用。 相似文献
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旨在通过构建受体相互作用蛋白1(RIP1)腺病毒干扰载体,研究其对BCG诱导的RAW264.7细胞凋亡相关指标的影响,以探讨其在BCG诱导RAW264.7凋亡过程中的调控作用。笔者构建RIP1腺病毒干扰载体,并转染感染BCG的小鼠RAW264.7细胞系,利用流式细胞仪检测各处理细胞凋亡率、细胞线粒体膜电位、细胞活性氧水平及细胞周期等指标,并用Western blot检测凋亡相关蛋白的表达水平。结果显示:BCG感染显著上调了RIP1的蛋白表达水平并提高了小鼠巨噬细胞RAW264.7的凋亡率,当RIP1被干扰后,BCG感染后的RAW264.7细胞凋亡率和活性氧水平显著降低,而促凋亡蛋白Bax表达量显著下调,线粒体膜电位和抑凋亡蛋白表达量上调。同时,BCG感染后细胞周期滞留于G_1期。BCG感染可有效上调RIP1表达量并诱导RAW264.7细胞凋亡。RIP1通过下调BCG感染后RAW264.7细胞的线粒体膜电位,上调活性氧含量并提高凋亡相关蛋白Bax/Bcl-2比值,使细胞周期阻滞于G_1期从而参与诱导细胞凋亡。 相似文献
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在建立肾小管上皮细胞体外培养模型的基础上,通过在培养液中添加不同浓度的醋酸镉和乙酰半胱氨酸(NAC),用CCK-8法测定细胞存活率,流式细胞仪检测细胞凋亡、细胞内活性氧与线粒体膜电位,探讨了镉对体外培养大鼠肾小管上皮细胞的毒性损伤及NAC的保护效应。结果显示,作用12 h,各染毒组与对照组相比,细胞存活率和线粒体膜电位显著下降(P0.05或P0.01),细胞凋亡率、坏死率、乳酸脱氢酶(LDH)漏出率和细胞内活性氧含量均显著升高(P0.05或P0.01),呈剂量-效应关系;而NAC保护组与染毒组相比,细胞存活率和细胞凋亡率均有显著差异(P0.05),细胞坏死率无明显差异(P0.05)。结果表明,本试验所选择的镉浓度引起的肾小管上皮细胞死亡是以凋亡为主,氧化应激直接参与镉对肾小管上皮细胞的毒性损伤,NAC对肾小管上皮细胞凋亡有一定的保护效应。 相似文献
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旨在探究玉米赤霉烯酮(ZEA)对鸡胚成纤维细胞(DF-1)的毒性作用机制,采用MTT法检测细胞活力变化,比色法检测乳酸脱氢酶(LDH)活力,ELISA法检测Caspase-3含量,Annexin V-FITC/PI双染法检测细胞凋亡,荧光显微镜观察细胞活性氧(ROS)水平,线粒体膜电位变化,RT-qPCR法检测内质网应激(ERs)和细胞凋亡相关基因的mRNA转录水平。结果显示,12.5~50.0 μg·mL-1 ZEA显著抑制DF-1细胞增殖(P<0.01),且呈时间和剂量依赖性关系。25.0 μg·mL-1 ZEA处理细胞24 h后,上清液中LDH和Caspase-3含量显著升高(P<0.01);细胞中ROS水平和细胞凋亡数量极显著升高(P<0.01);线粒体膜电位极显著降低(P<0.01)。凋亡相关基因Caspase-3、Bax mRNA转录水平极显著上调(P<0.01),Bcl-2 mRNA转录水平极显著下调(P<0.01);ERs相关基因GRP78、ATF6、ATF4、CHOP、PERK mRNA转录水平极显著上调(P<0.01)。综上表明,ZEA能通过内质网应激途径导致细胞凋亡并对鸡胚成纤维细胞发挥毒性作用。研究结果为深入研究ZEA对鸡细胞的毒性作用和解毒手段奠定基础,对相关禽类疾病治疗具有意义。 相似文献
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用不同浓度醋酸镉(0、5、10、20μmol/L)以及细胞内钙离子螯合剂BAPTA-AM(10μmol/L)单独或联合作用于大鼠大脑皮质神经细胞12h,利用流式细胞仪检测细胞凋亡率、细胞内[Ca2+];、活性氧(ROS)水平以及线粒体膜电位(△ψm)。结果显示,与对照组相比,各镉染毒组细胞凋亡率、细胞内[Ca2+]i和ROS水平显著或极显著升高(P〈0.05或P〈0.01),△ψm显著或极显著降低(P〈0.05或P〈0O.01)。BAPTA-AM联合组与相应镉染毒组相比,细胞凋亡率、细胞内[Ca2+]i和ROS水平降低,△ψm升高,部分组间差异显著或极显著(P〈0.05或P〈0.01)。结果表明,镉可诱导大脑皮质神经细胞凋亡,细胞内钙稳态失衡在镉诱导大脑皮质神经细胞凋亡中起着重要作用,凋亡机理可能与细胞内钙超栽引起ROS水平升高和△ψm下降有关。 相似文献
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旨在探讨钙稳态失衡在锰致体外培养鸡胚脑神经细胞凋亡中的作用。以体外培养鸡胚脑神经元为研究对象,在含终浓度为0、1.5、22、.5 mmol.L-1MnCl2的DMEM培养液中培养24 h,应用流式细胞仪检测磷脂酰丝氨酸(PS)和线粒体膜电位(ΔΨm),琼脂糖凝胶电泳法(DNA Ladder)检测细胞染色质的断裂,以Fura-3/AM为探针检测细胞内游离钙离子浓度([Ca2+]i),用实时定量PCR法检测细胞内CaMmRNA的表达水平。结果表明,随着MnCl2浓度的升高,ΔΨm呈降低趋势,PS膜外翻增加,细胞染色质DNA发生损伤,产生明显的梯形条带,细胞内[Ca2+]i呈升高趋势,CaMmRNA的表达水平下降。结果提示,过量锰通过抑制CaM活性,引起神经元内[Ca2+]i升高,膜通透性发生改变,ΔΨm降低,从而导致鸡胚脑神经元发生凋亡。 相似文献
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《畜牧兽医学报》2017,(9)
为探究伏马毒素B_1(FB_1)对人脐静脉血管内皮细胞(HUVEC)的毒性及作用机制,采用不同质量浓度的FB_1处理HUVEC,通过CCK-8法检测细胞活力,流式细胞术检测细胞周期,荧光显微镜观察细胞氧化应激,流式细胞术检测线粒体膜电位变化,Hoechst33342染色检测细胞凋亡,荧光定量PCR检测细胞凋亡相关基因的转录情况。结果显示:FB_1处理组在低质量浓度(2.5、5μg·mL~(-1))短时间(6、12h)处理后细胞活力变化不显著,超过此剂量和时间细胞活力显著降低(P0.05或P0.01),且质量浓度为10、20μg·mL~(-1) FB_1处理组活性氧(ROS)的荧光信号增强;FB_1处理组细胞周期由G_0/G_1期向S期转换时阻滞,细胞线粒体膜电位降低,细胞凋亡相关基因Caspase-3转录升高,Bcl-2转录显著降低(P0.05),Caspase-9和Bax转录极显著升高(P0.01)。结果表明,FB_1对人脐静脉血管内皮细胞有毒性作用,能抑制细胞增殖,使细胞周期阻滞在G0/G1期;能通过线粒体途径诱导HUVEC凋亡。研究结果为深入研究FB_1对人类细胞的毒性作用机制及相关疾病治疗奠定基础。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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以国际标准强毒R株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离MG,并收集感染鸡所产蛋分离MG。结果表明,人工感染48小时后上、下呼吸道及肺已被全面感染,96小时气囊已被感染,120小时输卵管已能分离到MG,卵巢始终分离不到MG。人工感染鸡自144小时便能在其所产蛋中分离出MG。药物治疗能在72小时内消除感染,油乳剂苗则需24天后逐渐降低蛋内MG分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内MG,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献