亚硝基胍对含XylE基因的pESnx／FL穿梭质粒克隆细胞的致突变作用

用诱变剂MNNG对含EB病毒类穿梭质粒的pESnx/FL克隆细胞进行致突变研究,MNNG对FL细胞的IC_(50)为1.25μg/ml,对以XylE为靶基因的克险细胞的诱发突变率为2～7×10~(-3),至少是克隆细胞自发突变率的27.8倍。随着MNNG的诱变剂量的增加,转化子数减少,突变子数增加,诱发突变率增加,诱变剂量与诱发突变率呈正相关剂量反应趋势。突变子的Cracking gel快速鉴定法表明,通过两次穿梭,质粒DNA仍能完整存在,且分子量无明显改变。因此,在DNA水平上,MNNG对靶基因XylE无大片段改变。     

渔药孔雀石绿致穿梭质粒pSP189靶基因突变研究

孔雀石绿是一种带有金属光泽的绿色结晶体,属三苯甲烷类染料。孔雀石绿中的化学功能团三苯甲烷具有高毒、高残留及“致畸、致癌、致突变”作用[1],美国、日本、英国等许多国家早已禁止用于水产养殖业。我国也于2002年5月将孔雀石绿列入《食品动物禁用的兽药及其化合物清单》中,     

MNNG所致哺乳类细胞非定标性突变的时相分析

ＭＮＮＧ所致哺乳类细胞非定标性突变的时相分析１孙雪敏１余应年张小山陈星若（浙江医科大学病理生理学教研室及医学分子生物学实验室，杭州３１００３１；１杭州医学高等专科学校，杭州３１００１２）非定标性突变（ｎｏｎｔａｒｇｅｔｅｄｍｕｔａｔｉｏｎ）为原核细胞...     

稀土化合物对 MNNG 致细胞转化的抑制作用

稀土化合物对ＭＮＮＧ致细胞转化的抑制作用崔明珍杨华赵素娟李申德１（北京市劳动卫生职业病防治研究所，北京１０００２０；１中国医学科学院肿瘤研究所，北京１０００２１）为探讨稀土对肿瘤防治的可能性，选用了农牧养殖业应用有代表性的硝酸稀土（ＲＥＮＯ３）和柠檬...     

甲基硝基亚硝基胍诱发的遗传不稳定vero细胞DNA体外复制的保真度

利用在猴肾ｖｅｒｏ细胞抽提物中建立的ＤＮＡ体外复制系统，对穿梭质粒ｐＺ１８９ＤＮＡ进行有效的复制后，将复制产物转化至Ｅ．ｃｏｌｉＭＢＭ７０７０，观察ｐＺ１８９质粒ＤＮＡ中突变靶基因ｓｕｐＦｔＲＮＡ基因突变的情况．在烷化剂甲基硝基亚硝基胍（Ｎ－ｍｅｔｈｙｌ－Ｎ′－ｎｉｔｒｏ－Ｎ－ｎｉｔｒｏｓｏｇｕａｎｉｄｉｎｅ）诱发的遗传不稳定（ｇｅｎｅｔｉｃｉｎｓｔａｂｉｌｉｔｙ）ｖｅｒｏ细胞胞浆抽提物中进行ｐＺ１８９质粒ＤＮＡ复制，发现经过体外复制的ｐＺ１８９质粒中ｓｕｐＦｔＲＮＡ基因突变率高出对照组５－８倍（Ｐ＜０．０５），证实该细胞ＤＮＡ复制系统的复制保真度明显降低     

甲基硝基亚硝基胍诱发的遗传不稳定vero细胞DNA体外复制的保真度

利用在猴肾vero细胞抽提物中建立的DNA体外复制系统，对穿梭质粒pZ189 DNA进行有效的复制后，将复制产物转化至E.coli MBM7070，观察pZ189质粒DNA中突变靶基因supF tRNA基因突变的情况．在烷化剂甲基硝基亚硝基胍(N-methyl-N′-nitro-N-nitrosoguanidine)诱发的遗传不稳定(genetic instability) vero细胞胞浆抽提物中进行pZ189质粒DNA复制, 发现经过体外复制的pZ189质粒中supF tRNA基因突变率高出对照组5-8倍(P<0.05)，证实该细胞DNA复制系统的复制保真度明显降低.     

基于雌激素代谢调控的白藜芦醇对MNNG诱导子宫内膜癌变的抑制作用

目的考察白藜芦醇(Res)是否可能通过调控雌激素内稳态,进而抑制MNNG诱导小鼠子宫内膜的癌变。方法采用MNNG诱导EC小鼠模型,将小鼠随机分为Control组、Res组、MNNG组、MNNG+Res组。HE染色观察组织病理情况;q PCR检测Ccnd1、CK-19、Erbb2 mRNA的表达;LC-MS/MS检测小鼠血清和子宫中E_1、E_2、2-MeOE_1、4-MeOE_1、2-MeOE_2、4-MeOE_2、16α-OHE_1、2-OHE_1、4-OHE_1、2-OHE_2和4-OHE_2的含量。结果 MNNG组小鼠子宫内膜腺体增多、拥挤,局灶形成筛孔;MNNG+Res组小鼠子宫内膜腺体减少,趋于正常。与Control组相比,MNNG组Ccnd1、Erbb2mRNA表达明显升高,MNNG+Res组明显降低。MNNG组小鼠的血清和子宫组织中,2-MeOE_2、2-MeOE_1和4-MeOE_1含量明显下降,4-OHE_2含量明显增加,给予Res治疗后,血清中4-MeOE_1含量明显升高,子宫组织中2-MeOE_2和2-MeOE_1含量明显升高,4-OHE_2在血清和子宫组织中含量均明显降低。结论 EC小鼠体内雌激素内稳态失衡,Res可以上调雌激素代谢产物2-MeOE_2的含量,降低4-OHE_2的含量,抑制EC的发生发展。     

稀土化合物对 MNNG 致细胞转化作用的影响

稀土化合物对ＭＮＮＧ致细胞转化作用的影响杨华１赵素娟１崔明珍１李申德２１．北京市劳动卫生职业病防治研究所（１０００２０）２．中国医学科学院肿瘤研究所细胞生物室稀土化合物在我国各个领域应用广泛，毒理学研究已证明在一定浓度下它是安全的［１］。为了开发稀土...     

几种香茶菜属二萜化合物对自由基导致线粒体损伤的保护作用

目的了解香茶菜属二萜类化合物冬凌草甲素（Ｏｒｉｄ）、腺花香茶素（Ａｄｅ）、黄花香茶菜素（Ｓｃｕｌ）是否具有抗氧化作用。方法用分光光度法测定脂质过氧化物丙二醛（ＭＤＡ）含量及线粒体肿胀度。用荧光分光光度法测定线粒体膜流动性。结果Ｏｒｉｄ,Ａｄｅ,Ｓｃｕｌ４０,８０,１６０μｍｏｌ·Ｌ－１抑制铁－半胱氨酸（Ｆｅ２＋－Ｃｙｓ）引起的肝线粒体ＭＤＡ形成,并呈剂量依赖关系。Ｏｒｉｄ,Ａｄｅ,Ｓｃｕｌ１６０μｍｏｌ·Ｌ－１抑制肝线粒体膜流动性下降（Ｐ值分别为２．２９７±０．０２２,０．３８９±０．００９,０．３８２±０．０１３,Ｆｅ２＋－Ｃｙｓ的Ｐ值为０．４２３±０．０１４）;Ａｄｅ１６０μｍｏｌ·Ｌ－１还可抑制脂质过氧化引起的肝线粒体肿胀。结论Ｏｒｉｄ,Ａｄｅ,Ｓｃｕｌ可能通过抑制脂质过氧化而产生抗氧化作用     

The effect of Calcicol as calcium tonic on delayed neurotoxicity induced by organophosphorus compounds

To examine whether delayed neuropathy is prevented or alleviated when Ca is administered to experimental animals before or after organophosphorus compounds (OPs) dosing, we observed the effects of Calcicol administration as a calcium tonic on delayed neurotoxicity by OPs in hens. The hens (n=28) were randomly divided into seven groups (four in each group). One group received glycerol formal as vehicle group, two groups received 30 mg/kg leptophos or 40 mg/kg triortho-cresyl phosphate (TOCP) (L group and T group), two groups received 2.4 mg/kg Ca(2+) (0.3 ml/kg Calcicol) 24 h before leptophos or TOCP administration, and the last two groups received 2.4 mg/kg Ca after leptophos or TOCP administration, respectively. Although delayed polyneuropathy induced by OPs could not be prevented completely by Calcicol, the clinical signs of organophosphorus-induced delayed neuropathy (OPIDN) in hens that received Calcicol soon before or after OPs administration were less severe than those in hens that received only OPs and there were significant differences in OPIDN score between groups (P<0.05). This shows that polyneuropathy and the recovery function of nerves and muscles suffering from polyneuropathy can be alleviated, as long as calcium tonic is administered before the clinical signs develop. This study offers hope of recovery to humans who are exposed to these OPs because of work, attempted suicide, accidental ingestion or other accidents, etc. Meanwhile, our results indicate further that there is a relationship between a decrease in Ca(2+) concentration in tissues and induction of delayed neuropathy.     

苯丙氨酸二肽类化合物Y101对刀豆蛋白A致小鼠免疫性肝损伤的保护作用

目的:观察苯丙氨酸二肽类化合物Y101(简称Y101)对刀豆蛋白A(CnoA)致小鼠免疫性肝损伤的保护作用,并探讨其可能的作用机制。方法:将昆明种小鼠随机分为生理盐水组、CnoA模型组、Y101低、中、高(25,50,100 mg.kg-1)剂量组和联苯双酯组(LB,150 mg.kg-1)。除生理盐水组外,CnoA模型组和各给药组均于d 5和d 7给药1 h后尾静脉注射20 mg.kg-1 CnoA溶液使之中毒(按0.1 mL/10 g体重)。末次中毒后禁食不禁水,8 h后眼球取血,并迅速取肝脏备检。检测其血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)含量。取肝脏,称重,检测肝脏中丙二醛(MDA)、一氧化氮(NO)、超氧化物歧化酶(SOD)、谷胱甘肽(GSH)的含量;另取肝脏做病理组织学检查。结果:与正常组比较,模型组小鼠血清中ALT、AST活性,肝内MDA、NO含量及肝脾指数显著升高(P<0.01),肝内SOD、GSH水平及胸腺指数明显降低(P<0.01)。低、中、高剂量Y101对肝损伤大鼠上述指标均有不同程度的改变,且呈良好的剂量关系。给予Y101治疗后,中、高剂量组的肝组织病理变化均明显轻于模型组。结论:Y101对CnoA致小鼠免疫性肝损伤具有保护作用,其作用机制可能与其抗氧化作用有关。     

The effect of antivenin on intramuscular pressure elevations induced by rattlesnake venom

The dose of an antivenin required to neutralize a clinical case of venom poisoning, as well as determining the timing or need to initiate antivenin treatment, is frequently difficult to objectively ascertain. In this study, venom from the southern Pacific rattlesnake, Crotalus viridis helleri, was injected into 29 dog hind limb anterolateral compartments. A solution of C. v. helleri venom (15 mg/ml) was prepared using dessicated venom and saline; 0.2 ml were injected sub-fascially so that each of the compartments received 3 mg of venom. In one group no antivenin was given, in a second group four vials of antivenin were administered i.v. 1 hr post-injection, and in the final group eight vials of antivenin were administered i.v. 1 hr following venom injection. In all groups intracompartment pressures, limb girth and surface temperature were measured at regular intervals over the first 48 hr. In the group receiving eight vials of antivenin the intracompartment pressure reached a peak mean pressure of 49 mm Hg at 2 - 4 hr, and then rapidly fell. In those treated with none or four vials the pressure rose to 70 and 60 mm Hg, respectively, and remained elevated over the first 24 hr. The difference between the former and latter two groups is statistically significant. The findings indicate that the intracompartmental pressure, and presumably destructive damage of the venom, can be controlled by adequate levels of i.v. antivenin. Intracompartmental pressure measurements should be considered as an adjunct in the monitoring and decision-making processes for the treatment of patients bitten by rattlesnakes.     

Glucan对氰化钾致肝细胞损伤的保护作用

目的观察氰化钾对肝细胞的损伤作用和Glucan的干预效果及作用机制。方法体外培养的SD乳鼠肝细胞 ,用氰化钾诱导损伤 ,用Glucan预先处理损伤组 ,观察正常对照组、损伤组、Glucan保护组肝细胞的活性 ,并检测培养上清液中的乳酸脱氢酶、超氧化物歧化酶活性和一氧化氮含量的变化。结果氰化钾可使肝细胞中的乳酸脱氢酶漏出增多 ,同时培养液中超氧化物歧化酶活性降低 ,一氧化氮含量减少 ,预先应用Glucan后 ,可部分逆转这些改变。结论Glucan对氰化钾所致的肝细胞损伤有保护作用     

Glucan在Con A所致免疫性肝损伤中的作用

目的观察Glucan对刀豆蛋白A(ConA)所致小鼠免疫性肝损伤的干预效果及其作用机制。方法ConA尾静脉注射制备小鼠免疫性肝损伤模型,在ConA注射前1h腹腔注射Glucan,观察正常对照组、ConA损伤组、Glucan/ConA组肝损伤的情况,检测血清谷丙转氨酶(ALT)、α肿瘤坏死因子(TNF-α)及组织中一氧化氮(NO)含量的变化,并用DNAladder检测肝细胞凋亡的变化。结果ConA尾静脉注射后,出现明显的肝损伤,血清ALT、TNF-α及组织中NO水平明显升高,DNAladder检测可见明显的梯状条带;预先应用Glucan后,可减轻这些改变。结论Glu-can对ConA所致小鼠免疫性肝损伤有保护作用。     

水飞蓟宾对内毒素血症心肌损伤的保护作用及机制

摘要：目的探究水飞蓟宾（SIL）对小鼠内毒素血症心肌损伤的保护作用和分子机制。方法24只C57BL/6小鼠分为对照（Control）组、SIL组、LPS组、LPS+SIL组,每组6只。通过腹腔注射脂多糖（LPS,10 mg/kg）制备内毒素血症心肌损伤小鼠模型。LPS注射前3 d,SIL组和LPS+SIL组每日通过灌胃方式给予SIL（100 mg/kg）,共给药3次;Control组和LPS组每日通过灌胃方式给予等量（0.2 mL）生理盐水,共灌胃3次。LPS注射6 h后超声检测各组小鼠心脏收缩功能;ELISA检测血清IL-1β和TNF-α表达水平;DHE染色观察各组小鼠心肌组织内活性氧（ROS）产量;TUNEL染色检测心肌凋亡率;Western blot检测凋亡相关蛋白Bax、Bcl-2、Caspase 3和NOX2表达。结果与Control组相比,LPS组小鼠左心室射血分数、左心室短轴缩短率和Bcl-2表达量明显降低,而ROS产量、NOX2、Bax、Caspase 3、IL-1β与TNF-α表达量以及心肌凋亡率明显增加（P＜0.05）。与LPS组相比,LPS+SIL组经水飞蓟宾预处理后可明显改善LPS引起的上述改变（P＜0.05）。与Control组相比,单纯给予SIL干预对上述指标的变化无明显影响（P＞0.05）。结论水飞蓟宾可有效缓解内毒素血症心肌损伤,其作用可能与抑制氧化应激、炎症反应和抗凋亡有关。