共查询到19条相似文献，搜索用时 406 毫秒
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本文进行了洛克沙胂对鲫鱼的急性毒性试验，并通过洛克沙胂的急性暴露胁迫试验对抗氧化系统的影响进行了探讨。洛克沙胂对鲫鱼的急性毒性较低，24h LC50为181.69mg／L，48h LC50和96h LC50均为176．57mg／L。按洛克沙胂30、45mg／L浓度(以As计)连续暴露5天，洛克沙胂对鱼脑和肝乳酸脱氢酶有显著的抑制作用并呈剂量-效应关系。鱼脑和肝丙二醛含量显著升高,脑、鳃和肝超氧化物歧化酶活性在初期显著增强,后期随剂量增高而受到显著抑制。鱼脑谷胱甘肽-S-转移酶受到极显著的抑制。结果表明：洛克沙胂对鲫鱼巯基酶和抗氧化功能有明显抑制．鱼脑和肝脏氧化损伤最明显，呈现一定的剂量-效应关系。 相似文献
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《黑龙江畜牧兽医》2016,(19)
为了研究洛克沙胂对秀丽隐杆线虫的毒性作用,试验利用模式生物秀丽隐杆线虫分别进行洛克沙胂的致死试验[0(空白对照)~10 000μg/L]、运动毒性试验[0(空白对照)~500μg/L]、生殖毒性试验[0(空白对照)~500μg/L]、寿命毒性试验[0(空白对照)~500μg/L],暴露24 h。通过检测秀丽隐杆线虫的24 h死亡率、第一代和第二代线虫头部摆动频率与身体弯曲频率,以及第一代产卵数目与世代时间、半数死亡时间和寿命等相关评价指标,对洛克沙胂毒性作用进行综合评价。结果表明:与对照组比较,各浓度洛克沙胂暴露组秀丽隐杆线虫第一代和第二代线虫头部摆动频率与身体弯曲频率降低,第一代产卵数目减少,世代时间延长,寿命缩短,差异均有统计学意义(P0.01);随着洛克沙胂暴露浓度的升高,秀丽隐杆线虫第一代和第二代线虫头部摆动频率与身体弯曲频率、第一代产卵数目、世代时间、寿命均存在显著的浓度-效应关系。说明洛克沙胂对秀丽隐杆线虫的运动能力、生殖系统以及寿命都有不良影响,秀丽隐杆线虫可以作为一种有效评价洛克沙胂毒性的生物指示物。 相似文献
3.
在建立猪粪中洛克沙胂HPLC检测方法基础上,选用24头育肥猪,分别混饲给予0、25、50、100 mg/kg洛克沙胂,混饲给药后不同时间采集粪样,以高效液相色谱法测定其中洛克沙胂质量浓度,了解洛克沙胂混饲给药后在猪体内的排泄情况,然后从江苏和山东省15个使用洛克沙胂的集约化猪场采集150头猪的粪样,调查猪粪样中的洛克沙胂含量。结果表明,所建立的猪粪中洛克沙胂HPLC检测方法的平均回收率为82.09%~84.03%,变异系数为2.92%~5.45%,检测限为0.05 mg/kg,定量限为0.1 mg/kg;以不同剂量混饲给药后,洛克沙胂在粪中排泄量在36~48 h达峰,峰质量浓度分别为12.31、22.52、34.78 mg/kg,猪粪中检测不到洛克沙胂的时间分别为72、108、132 h;所调查150个粪样中洛克沙胂平均质量浓度为23.13 mg/kg。 相似文献
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为探讨F-2毒素对雄性生殖机能的影响,取大鼠睾丸支持细胞进行体外培养,运用单细胞凝胶电泳技术检测51、0、20和40 mg/L的F-2毒素攻毒后24 h支持细胞DNA的损伤情况。结果显示,F-2毒素在一定浓度范围内对体外培养的支持细胞DNA产生损伤作用,且受损程度随着F-2毒素攻毒剂量而升高,具有明显量效关系。除5 mg/L剂量组外,其余各组的细胞受损率、彗星尾长和DNA损伤程度与阴性对照组相比差异极显著（P〈0.01）,表明F-2毒素对体外培养的大鼠睾丸支持细胞有毒性作用,能够损伤细胞DNA。 相似文献
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以体外培养的小鼠睾丸间质细胞系TM3 为材料,加入不同质量浓度的钼酸钠溶液（0,10,20,40,80,160mg/L）染毒培养,分别在干预4,8,12,24,48h采用MTT法检测细胞的增殖。干预48h后,采用流式细胞术检测细胞周期和凋亡,单细胞凝胶电泳检测DNA损伤的变化。结果表明：与对照组相比,不同剂量钼酸钠作用24h后,睾丸间质细胞的增殖活性均受到抑制;不同质量浓度的钼酸钠作用48h后,细胞周期阻滞于G0/G1期,20mg/L及其以上剂量组G0/G1期细胞百分率与对照组相比显著升高（P〈0.05或P〈0.01）;与对照组相比,各剂量组TM3 小鼠睾丸间质细胞凋亡率显著升高,差异极显著（P〈0.01）;细胞尾部DNA含量及细胞尾长随着钼剂量的增加呈不同程度的增加,且存在着剂量—效应关系。结论说明钼能够引起睾丸间质细胞周期的紊乱,并诱导睾丸间质细胞发生DNA损伤和凋亡。 相似文献
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以体外培养的小鼠睾丸间质细胞系TM3 为材料,加入不同质量浓度的钼酸钠溶液(0,10,20,40,80,160mg/L)染毒培养,分别在干预4,8,12,24,48h采用MTT法检测细胞的增殖。干预48h后,采用流式细胞术检测细胞周期和凋亡,单细胞凝胶电泳检测DNA损伤的变化。结果表明:与对照组相比,不同剂量钼酸钠作用24h后,睾丸间质细胞的增殖活性均受到抑制;不同质量浓度的钼酸钠作用48h后,细胞周期阻滞于G0/G1期,20mg/L及其以上剂量组G0/G1期细胞百分率与对照组相比显著升高(P<0.05或P<0.01);与对照组相比,各剂量组TM3 小鼠睾丸间质细胞凋亡率显著升高,差异极显著(P<0.01);细胞尾部DNA含量及细胞尾长随着钼剂量的增加呈不同程度的增加,且存在着剂量—效应关系。结论说明钼能够引起睾丸间质细胞周期的紊乱,并诱导睾丸间质细胞发生DNA损伤和凋亡。 相似文献
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本试验旨在研究6-苄氨基嘌呤(6-BA)对大鼠小肠缺血再灌注(I/R)损伤的保护作用。选取80只雄性SD大鼠,随机分为4组,即对照组、I/R模型组和低、高剂量6-BA组。低、高剂量6-BA组于术前3周分别连续灌胃10、20mg/kg的6-BA,对照组和I/R模型组灌胃同体积的生理盐水,每天1次。对照组在暴露肠系膜上动脉后不做阻断;I/R模型组和低、高剂量6-BA组阻断肠系膜血管30min后再灌注60min。随后取大鼠空肠组织分别进行总超氧化物歧化酶(T-SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性和丙二醛(MDA)含量检测;采用单细胞凝胶电泳法检测细胞DNA损伤程度,采用免疫组化法检测半胱氨酸天冬氨酸特异性蛋白酶3(Caspase-3)表达情况。结果显示,与I/R模型组相比,补充10、20 mg/kg的6-BA后,T-SOD、GSH-Px活性显著升高(P0.05),MDA含量显著降低(P0.05);小肠细胞DNA的拖尾现象好转,尾部DNA含量和拖尾率都显著低于I/R模型组(P0.05);Caspase-3阳性表达细胞数量显著减少(P0.05)。由此可见,10、20 mg/kg的6-BA能有效防护I/R对小肠的损伤,且20mg/kg的6-BA作用效果尤为明显。 相似文献
9.
为了研究毒氟磷致小鼠遗传毒性,试验将小鼠外周血淋巴细胞悬液随机分成5组,第1组为D-Hank’s阴性对照组;第2,3,4组为试验组,分别用30%毒氟磷可湿性粉剂按1 mg/L、5 mg/L、10 mg/L剂量进行体外染毒;第5组为10μmol/L阿霉素阳性对照组。通过MTT法测定毒氟磷对细胞的增殖抑制作用,并对DNA损伤进行彗星试验(SCGE)分析。结果表明:1 mg/L、5 mg/L、10 mg/L毒氟磷对细胞的抑制率分别为(6.751±0.021)%、(11.521±0.009)%、(16.254±0.022)%;5 mg/L毒氟磷可致小鼠外周血淋巴细胞DNA损伤,随着染毒剂量的增加DNA受损程度加剧,呈现剂量-效应关系。 相似文献
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采用Chang Liver和L-02 2株人源肝细胞为生物材料,通过细胞生长抑制试验、DNA损伤分析、兴奋性试验,观测喹烯酮和喹乙醇不同作用剂量和作用时间下对细胞生长的影响,对细胞DNA尾长、尾部DNA百分含量和Oliver尾距的影响以及低剂量药物对细胞兴奋效应的诱导作用,并进行统计分析。结果显示,高剂量喹烯酮和喹乙醇对Chang Liver细胞作用24 h的最高抑制率分别达73.29%和31.88%,对L-02细胞作用24 h的最高抑制率分别达76.51%和39.7%,且抑制作用呈剂量和时间相关性,但低剂量喹烯酮也能诱导L-02细胞产生兴奋效应(P0.01);同时,细胞DNA尾长、尾部DNA百分含量和Oliver尾距随药物剂量的增加而不断上升,证明2种药还可显著诱导这2株细胞的DNA损伤(P0.01),且喹乙醇导致的损伤比喹烯酮严重。结果表明,喹烯酮和喹乙醇对人肝细胞均具有一定的毒性,但喹烯酮的毒性作用比喹乙醇小。 相似文献
11.
改良彗星实验检测黄曲霉毒素B_1致雏鸭DNA损伤 总被引：1，自引：0，他引：1
试验旨在通过改良彗星实验检测黄曲霉毒素B1(aflatoxi-B1,AFB1)对雏鸭肝细胞DNA损伤的影响.锥鸭经AFB1灌胃染毒,2 h后分离肝细胞,并通过改良彗星实验测定DNA损伤.结果显示,AFB1能够导致雏鸭肝细胞DNA损伤,表现为尾长、尾部DNA百分含量、尾矩、Olive尾矩等彗星参数与空白和溶剂对照组相比显著增加(P<0.05).表明改良彗星实验能够用于AFB1导致肝细胞DNA损伤的检测,试验还提示,在体肝细胞彗星实验能够作为雏鸭AFB1暴露的遗传毒性标志物. 相似文献
12.
试验旨在通过改良彗星实验检测黄曲霉毒素B1（aflatoxin-B1,AFB1）对雏鸭肝细胞DNA损伤的影响。雏鸭经AFB1灌胃染毒,2 h后分离肝细胞,并通过改良彗星实验测定DNA损伤。结果显示,AFB1能够导致雏鸭肝细胞DNA损伤,表现为〖JP2〗尾长、尾部DNA百分含量、尾矩、Olive尾矩等彗星参数与空白和溶剂对照组相比显著增加（P<0.05）。表明改良彗星实验能够用于AFB1导致肝细胞DNA损伤的检测,试验还提示,在体肝细胞彗星实验能够作为雏鸭AFB1暴露的遗传毒性标志物。 相似文献
13.
The relationship between cellular radiosensitivity and radiation-induced DNA damage measured by the comet assay 总被引：4，自引：0，他引：4
Wada S Kurahayashi H Kobayashi Y Funayama T Yamamoto K Natsuhori M Ito N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(4):471-477
The relationship between deoxyribonucleic acid (DNA) damage and the cell death induced by gamma-irradiation was examined in three kinds of cells, Chinese hamster ovary fibroblast CHO-K1, human melanoma HMV-II and mouse leukemia L5178Y. Cell survival was determined by a clonogenic assay. The induction and rejoining of DNA strand breaks induced by radiation were measured by the alkaline and neutral comet assays. L5178Y cells were the most radiosensitive, while CHO-K1 cells and HMV-II cells were radioresistant. There was an inverse relationship between the survival fraction at 2 Gy (SF2) and the yield of initial DNA strand breaks per unit dose under the alkaline condition for the comet assay, and also a relationship between SF2 and the residual DNA strand breaks (for 4 hr after irradiation) under the neutral condition for the comet assay, the latter being generally considered to be relative to cellular radiosensitivity. In the present analysis, it was considered that the alkaline condition for the comet assay was optimal for evaluating the initial DNA strand breaks, while the neutral condition was optimal for evaluating the residual DNA strand breaks. Since the comet assay is simpler and more rapid than other methods for detecting radiation-induced DNA damage, this assay appears to be a useful predictive assay for evaluating cellular clonogenic radiosensitivity of tumor cells. 相似文献
14.
Detection of radiation-induced apoptosis using the comet assay 总被引：2，自引：0，他引：2
Wada S Khoa TV Kobayashi Y Funayama T Yamamoto K Natsuhori M Ito N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(11):1161-1166
The electrophoresis pattern of apoptotic cells detected by the comet assay has a characteristic small head and spread tail. This image has been referred to as an apoptotic comet, but it has not been previously proven to be apoptotic cells by any direct method. In order to identify this image obtained by the comet assay as corresponding to an apoptotic cell, the frequency of appearance of apoptosis was examined using CHO-K1 and L5178Y cells which were exposed to gamma irradiation. As a method for detecting apoptosis, the terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) assay was used. When the frequency of appearance of apoptotic cells following gamma irradiation was observed over a period of time, there was a significant increase in appearance of apoptosis when using the TUNEL assay. However, there was only a slight increase when using the comet assay. In order to verify the low frequency of appearance of apoptosis when using the comet assay, we attempted to use the TUNEL assay to stain the apoptotic comets detected in the comet assay. The apoptotic comets were TUNEL positive and the normal comets were TUNEL negative. This indicates that the apoptotic comets were formed from DNA fragments with 3'-hydroxy ends that are generated as cells undergo apoptosis. Therefore, it was understood that the characteristic pattern of apoptotic comets detected by the comet assay corresponds to cells undergoing apoptosis. 相似文献
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The effects of dietary nucleotides on thymocyte DNA damages induced by cyclophosphamide (CP) in mice were examined. First, phase I experiment was conducted to determine the optimal timing of detecting thymocyte DNA damages induced by CP (150 mg/kg body weight) in mice. Thymocyte DNA damages was determined at 6, 12, 18, 24 h by single-cell gel electrophosphoresis assay (comet assay) after intraperitoneal injection of CP. The levels of DNA damage at 6, 12, 18, 24 h were all significantly higher than that of the control group (p < 0.01). The highest level of DNA damage appeared at 18 h and then decreased at 24 h. Therefore, 18 h was selected to determine DNA damages induced by CP in subsequent experiments. In phase II experiment, 30 male KunMing mice were divided into three treatments: negative control (NC), positive control (PC) and nucleotides group (NG). Mice in NC and PC were fed nucleotide-free diet, and mice in NG were fed nucleotide-supplemented diet (supplemented with 0.25% nucleotides, a mixture containing equal amounts of AMP, CMP, GMP and UMP). Mice in PC and NG groups were injected with CP (150 mg/kg body weight) at 21 days. DNA damage in thymocytes was evaluated at 18 h after CP treatment. The results indicate that dietary nucleotides do not affect the weights of the thymus and the spleen, or their organ indices (p > 0.05), but significantly decrease the percentage of comet cells and comet tail sizes (p < 0.01). This study demonstrates that dietary nucleotides could reduce the level of thymocyte DNA damage induced by CP in mice. 相似文献
17.
Mohamed Tharwat Aya Takamizawa Yoshinao Z. Hosaka Daiji Endoh Shin Oikawa 《Canadian journal of veterinary research》2012,76(4):241-247
The objective of this study was to investigate hepatocyte apoptosis in dairy cows during the transition period. Four clinically healthy, pregnant dairy cattle were used. The cows had no clinical diseases throughout this study. Blood samples were collected and livers were biopsied from the cows at 3 different times: 3 weeks before expected partition (wk −3); during parturition (wk 0), and 3 weeks (wk +3) after parturition. The damage to deoxyribonucleic acid (DNA) caused by hepatocytes was evaluated by comet assay. The apoptotic features of hepatocytes were examined by immunohistochemistry and electron microscopic analyses. The hepatic triglyceride content markedly increased at wk 0 and wk +3 compared with the values at wk −3. The results of the comet assay showed increases in the mean tail moment values of hepatic cells after parturition in all cows, which suggested increased DNA damage. Histopathologically, the hepatocytes began to contain lipid droplets at wk 0 and were severely opacified at wk +3. Caspase-3-positive and single-stranded DNA-(ssDNA)-positive cells were first detected in the liver after parturition. Condensation of nuclear chromatin, a typical sign of apoptosis, was confirmed by transmission electron microscopy after parturition. These results suggest that apoptosis is induced in hepatocytes of dairy cows around parturition and may result from lipotoxicity in hepatocytes. 相似文献
18.
研究旨在筛选最适合猪MⅡ期卵母细胞玻璃化冷冻的冷冻液,并探究玻璃化冷冻对猪MⅡ期卵母细胞DNA的影响。选取目前应用最多的7种冷冻液（分别为1、2、3、4、5、6、7组）,将MⅡ期卵母细胞随机分为8组,其中对照组直接进行孤雌激活,其余7组分别进行7种冷冻液处理后不经液氮冷冻直接于解冻液中解冻,解冻后进行孤雌激活,通过卵裂率、囊胚率和囊胚细胞数的统计结果筛选出最适冷冻液;应用筛选的3种冷冻液,进行猪MⅡ期卵母细胞玻璃化冷冻,解冻后恢复2 h,统计卵母细胞形态正常率,孤雌激活44~48 h统计卵裂率;应用透射电子显微镜观察正常MⅡ期卵母细胞与玻璃化冷冻-复苏后的MⅡ期卵母细胞超微结构的变化;将猪MⅡ期卵母细胞随机分成对照组、冷冻液处理组和冷冻组,应用彗星电泳技术检测玻璃化冷冻对卵母细胞DNA的损伤。结果发现,与对照组相比,除5组卵裂率、1组囊胚率显著降低（P<0.05）外,其余各组卵裂率、囊胚率均差异不显著（P>0.05）;各组间囊胚细胞数均低于对照组,但差异均不显著（P>0.05）,3、6、7组卵裂率和囊胚率较高;玻璃化冷冻-解冻后,7组卵母细胞的形态正常率、卵裂率均显著低于3、6组（P<0.05）,6组卵裂率高于3组;MⅡ期卵母细胞移入预处理液中后可见明显的皱缩,移入冷冻液中迅速脱水,解冻后可见卵母细胞透明带断裂,胞质皱缩、分布不均;透射电子显微镜下,冷冻后猪MⅡ期卵母细胞透明带及细胞膜损伤,微绒毛严重损伤甚至消失,皮质颗粒排列在质膜下且数量减少,脂滴形态破坏、形成空泡,内质网与脂滴的联系损坏,线粒体肿胀、嵴不明显;彗星电泳发现,与对照组相比,冷冻液处理组头部DNA、尾部DNA和Olive尾矩值均差异不显著（P>0.05）,有彗星拖尾现象;冷冻组头部DNA损伤、尾部DNA损伤与Olive尾矩值均显著高于冷冻液处理组和对照组（P<0.05）,有明显彗星拖尾现象。结果表明,以二甲基亚砜（DMSO）和乙二醇（EG）为主要成分的冷冻液适于猪MⅡ期卵母细胞玻璃化冷冻;玻璃化冷冻对猪MⅡ期卵母细胞超微结构及其DNA存在一定损伤作用,其损伤机制有待进一步研究。 相似文献
19.
通过贝鲁特反应和还原、脱羧反应在体外合成制备3-甲基喹噁啉-2-羧酸,并进行理化鉴定和抗菌活性测试;通过MTT方法研究3-甲基喹噁啉-2-羧酸对多种细胞的生长抑制作用,利用单细胞电泳研究其对细胞DNA的损伤作用,利用流式细胞术研究其对细胞周期的改变。结果显示,体外成功合成制备出3-甲基喹噁啉-2-羧酸,而3-甲基喹噁啉-2-羧酸几乎没有抗菌效果,对多种细胞的生长抑制作用较弱,在剂量检测范围内细胞抑制率不到30%,但在一定剂量下能导致细胞DNA损伤,主要表现为尾长和尾部DNA含量显著升高;并且3-甲基喹噁啉-2-羧酸也能改变Chang细胞的细胞周期,表现为S期阻滞。结果表明,3-甲基喹噁啉-2-羧酸具有一定的细胞毒性。 相似文献