醋氯芬酸的鼠伤寒沙门氏菌诱变性试验

应用鼠伤寒沙门氏菌回复突变试验研究了醋氯芬酸的诱变作用。试验选用TA97,TA98,TA100,TA102菌株。当醋氯芬酸的浓度在1,10,100,1000,4000μg/皿,无论加或不加S_9混合物时其对四株沙门氏菌株的回复突变作用均为阴性。结果表明,醋氯芬酸在体外对原核细胞无诱变作用。     

尼索地平的鼠伤寒沙门氏菌诱变性试验

应用鼠伤寒沙门氏菌回复突变试验研究了尼索地平的诱变作用.试验选用TA97,TA98,TA100,TA102菌株.当尼索地平的浓度在0.1,1,10,100,1000μg/皿,无论加或不加S9混合物,其对四株沙门氏菌株的回复突变作用均为阴性.结果表明,尼索地平在体外对原核细胞无诱变作用.     

黄芩苷胶囊细菌回复突变试验

目的对黄芩苷胶囊进行细菌回复突变试验,以评价其遗传毒性。方法采用直接平皿掺入法,将胶囊以每皿5,1,0.2,0.04和0.008mg黄芩苷为终浓度在活化与非活化条件下,与鼠伤寒沙门氏菌组氨酸缺陷型突变菌株,37℃接触72h,计数回变菌落数。结果5～0.008mg黄芩苷各组在+S9与-S92种测试系统条件下,各菌株回变菌落数与阴性对照相比无统计学意义差异,回变菌落背景正常,未显示其有抑菌作用和沉淀,且无剂量-反应关系。结论黄芩苷胶囊药粉在该实验条件下对测试菌株无潜在致突变性。     

Ames试验检测不同工艺制作灵香草浸膏的致突变性

Ａｍｅｓ试验检测不同工艺制作灵香草浸膏的致突变性刘淑英，孙毓柏，魏运莲，张文俊，张文郁Ａｍｅｓ试验是美国环保局（ＥＰＡ）确定的化学物质远期安全评价组合试验中的首选方法。文献报道，以细菌致突变试验方法检测化学物质的可靠性达８５～９５％［１～３］。因此，...     

泰格列净Ames试验研究

目的 应用Ames试验探讨泰格列净是否具有致突变性。方法 采用标准平板掺入法,应用组氨酸营养缺陷型鼠伤寒沙门氏菌TA97、TA98、TA100、TA102和TA1535对泰格列净进行回复突变试验。结果 在31.25～2 000μg/皿剂量范围内,加和不加大鼠肝微粒体酶S9平行条件下测试,泰格列净Ames回复突变试验结果为阴性。结论 在本试验条件下,泰格列净无致突变性。     

拉呋替丁的临床应用

拉呋替丁为第二代H2受体拮抗剂,可持续地抑制胃酸、胃蛋白酶的基础分泌、夜间分泌及四肽胃泌素等刺激因子引起的分泌,对抗多种胃刺激因子引起的胃黏膜损伤。本品主要治疗胃溃疡和十二指肠溃疡,可改善急性胃炎、慢性胃炎急性恶变期的黏膜病变,安全、有效、持久,具有良好的市场前景。     

一种灵敏的细菌正向突变试验方法

目前已建立的遗传毒性检测技术有 2 0 0多种 ,其中 ,Ames试验最为常用。Ames试验 ,也就是鼠伤寒沙门菌组氨酸营养缺陷型的回复突变试验 ,是Ames等在70年代建立起来的。 1983年 ,Maron和Ames把该方法规范化 ,选用鼠伤寒沙门菌的 4种品系 (TA97,TA98,T10 0 ,TA10 2 )为标准菌株来检测外源化学物的致突变能力[1 ] 。这种方法被许多实验室采纳 ,广泛用于检测食品、化妆品、药品和饮用水等测试样中的致变物。但是 ,有 2个客观事实限制了它的应用 :(1)某些DNA分子诱变物不能使所用的细菌品系发生回变 ,因此 ,回复突变试验就不能用于这类物质…     

尼索地平的鼠伤寒伤门氏菌诱变性试验

应用鼠伤寒沙门氏菌回复突变试验研究了尼索地平的诱变作用。试验选用ＴＡ９７，ＴＡ９８，ＴＡ１００，ＴＡ１０２菌株。当尼索地平的浓度在０．１，１０，１００，１０００ｕｇ／皿，无论加或不加Ｓ９混合物，其对四株沙门氏菌株的回复突变作用均为阴性。结果表明，尼索地平在体外对原核细胞无诱变作用。     

地红霉素的AMES试验

目的:检测地红霉素的致突变活性.方法:采用组氨酸营养缺陷型鼠伤寒沙门杆菌TA系列4个菌株.试验在有和无代谢活化剂下对受试药品0.08～50μg·皿-1共5个浓度组进行测试.结果:各菌株回复突变菌落数未见明显增多.结论:地红霉素无致突变活性.     

依布硒啉的致突变试验

我们对山东省医学科学院药物研究所提供的新药依布硒啉进行了Ａｍｅｓ试验、小鼠骨髓嗜多染红细胞微核试验和染色体畸变试验。1　Ａｍｅｓ试验用标准平板掺入法进行 ,依布硒啉浓度为 1、10、10 0、10 0 0、5 0 0 0 μｇ 皿 ,并设有阴、阳性对照 ,对鼠伤寒沙门氏菌ＴＡ97、ＴＡ98、ＴＡ10 0、ＴＡ10 2 4种菌株无论加Ｓ9与不加Ｓ9的 ,依布硒啉诱变菌落数均未超过自发回变菌落数的两倍 ,结果为阴性。2　小鼠骨髓嗜多染红细胞微核试验选用昆明种小鼠 ,雌雄各 2 5只 ,随机分为依布硒啉10 0 0 ,5 0 0 ,2 5 0ｍｇ ｋｇ组和阴、阳性对照共 5组 ,连续…     

Evaluation of the mutagenicity of simple substituted quinoxalines in Salmonella typhimurium

Limited information is available on the genotoxicity of simple quinoxalines, distinct from the food related carcinogenic derivatives bearing an aromatic amino group. Isolated positive results, with no apparent structure–activity relationships, were reported in earlier studies on alkyl substituted quinoxalines, raising a safety concern in some regulatory authorities in view of the potential human exposure related to their use as food flavors. In order to elucidate the genotoxic hazard posed by simple quinoxalines, in this work a random set of mono- and bi-substituted methyl, chloro- and hydroxyl- quinoxalines have been tested in an OECD-compliant bacterial reversion test (TG 471). The results obtained do not highlight any genotoxic potential in the set of quinoxalines examined, and suggest that this may be a common trait for other simple substituted quinoxalines. Earlier published positive findings were not confirmed in this work, which call for a cautious approach in the use of literature data for regulatory purpose.     

Antimutagenic and anticlastogenic effects of Turkish Black Tea on TA98 and TA100 strains of Salmonella typhimurium (in vitro) and mice (in vivo)

Context: Black tea has been reported to have significant antimutagenic and anticarcinogenic properties associated with its polyphenols theaflavins (TF) and thearubigins (TR). Similarly, Turkish black tea (TBT) also contains a considerable amount of TF and TR.

Objective: This study investigated the mutagenic, antimutagenic and anticlastogenic properties of TBT.

Materials and methods: The mutagenic and antimutagenic effects of TBT (10 to 40000?μg/plate) were investigated in vitro on Salmonella strains TA98 and TA100 with and without S9 fraction. Anticlastogenic effect was studied at concentrations of 300–1200?mg/kg TBT extract by chromosomal aberrations (CA) assay from bone marrow of mice.

Results: The results of this study did not reveal any mutagenic properties of TBT. On the contrary, TBT extract exhibited antimutagenic activity at >1000?μg/plate concentrations in TA98 strain with and without S9 activation (40% inhibition with S9 and 27% without S9). In TA100 strain, the antimutagenic activity was observed at?>20,000?μg/plate TBT extracts without S9 activation (28% inhibition) and at >1000?μg/plate with S9 activation (59% inhibition). A significant decrease in the percentage of aberrant cells (12.33%?±?1.27) was observed in dimethylbenz(a)anthracene (DMBA) plus highest concentration (1200?mg/kg) of TBT extract-treated group when compared to only DMBA-treated group (17.00%?±?2.28).

Discussion and conclusion: Results indicated that TBT can be considered as genotoxically safe, because it did not exert any mutagenic and clastogenic effects. As a result, TBT exhibited antimutagenic effects more apparently after metabolic activation in bacterial test system and had an anticlastogenic effect in mice.     

Extracellular and intracellular anti-mutagenic effects of bile pigments in the Salmonella typhimurium reverse mutation assay

In vitro anti-genotoxic properties of bile pigments have been explored and confirmed recently. Despite these reports mechanisms to explain DNA protection by endogenous bile pigments remain unclear. Surprisingly, the quantification of cellular pigment absorption which could represent a fundamental prerequisite for intracellular (e.g., anti-mutagenic) effects, has not been explored. Therefore, we aimed to measure the amounts of un-/conjugated bilirubin as well as biliverdin absorbed into colonies of Salmonella typhimurium, utilising HPLC analyses, and to observe whether intracellular compound concentrations could predict anti-genotoxic effects. HPLC analyses confirmed that bacterial bile pigment absorption was concentration-dependent. Plate bile pigment concentrations were inversely associated with genotoxicity of all tested mutagens, irrespective of strain and test conditions. However, protection against frame-shift mutation in strain TA98 most strongly depended on the bacterial absorption of bilirubin and biliverdin, which indicates that bile pigments can protect by intercepting mutations extracellularly and specifically inhibit frame-shift mutations intracellularly.     

白眉蝮蛇毒精氨酸酯酶Ames试验(英文)

目的　研究白眉蝮蛇 (Agkistrodonhalysussuriensis)毒中精氨酸酯酶的致突变作用。 方法　用鼠伤寒沙门细菌营养缺陷型突变株TA97,TA98,TA10 0和TA10 2 ,采用平皿掺入法进行Ames试验 ,将实验分为加和不加代谢激活系统S92组平行试验。精氨酸酯酶设 6个浓度 :10 .0× 10 -3 ,5 .0× 10 -3 ,2 .5× 10 -3 ,1.2 5× 10 -3 ,0 .6 2 5× 10 -3 和 0 .312× 10 -3 U/mL。结果　加和不加代谢激活系统S9两种条件下 ,精氨酸酯酶不诱发鼠伤寒沙门细菌营养缺陷型突株的回复突变。Ames试验结果为阴性。结论　从致突变角度考虑 ,精氨酸酯酶在高于“蝮蛇清栓酶”(主要成分为精氨酸酯酶 )临床治疗剂量约 10 0 0倍的条件下仍然较安全。     

Multi-walled carbon nanotubes: Lack of mutagenic activity in the bacterial reverse mutation assay

The mutagenic effect of multi-walled carbon nanotubes (MWCNTs) characterised by small surface/volume ratio, high diameter and less than 0.1% of metal contaminants was evaluated by the bacterial reverse mutation assay (Ames test) on Salmonella typhimurium TA 98 and TA 100 strains, and on Escherichia coli WP2uvrA strain, in presence and in absence of the metabolic activation system S9. A preliminary cytotoxicity assay was carried out to ensure that cytotoxicity did not interfere with response.     

二乙基二硫代氨基甲酸钠抑制顺铂的致突变作用

二乙基二硫代氨基甲酸钠（ＤＤＴＣ）能明显抑制顺铂诱导鼠伤寒沙门氏菌ＴＡ１００，ＴＡ９８回变，有Ｓ９代谢活化系统时抑制作用增强，１６０．７４μｇ／ｐｌａｔｅＤＤＴＣ对０．２５～２．００μｇ／ｐｌａｔｅ顺铂抑制率为８７．４％～９５．７％（ＴＡ１００）和８９．４％～１０５．５％（ＴＡ９８）．小鼠ｉｐ顺铂１．５ｍｇ·ｋｇ－１，２４ｈ重复ｉｐ１次，每次给顺铂后１ｈｉｐＤＤＴＣ４００～８００ｍｇ·ｋｇ－１或同时ｉｇＤＤＴＣ７５０～１５００ｍｇ·ｋｇ－１．可显著降低顺铂诱发小鼠骨髓多染红细胞微核的形成．体内外实验结果表明ＤＤＴＣ可降低顺铂的致突变作用     

Inhibition of the mutagenic effects of N-methyl-N'-nitro-N-nitrosoguanidine and 9-Aminoacridine by indenopyridines in the Salmonella typhimurium tester strain 1537 and E. coli

Abstract

The goal of the present research was to determine the protective potential of five newly synthesized indenopyridine derivatives against N-methyl-N’-nitro-N-nitrosoguanidine (MNNG) and 9-aminoacridine (9-AA) induced mutagenesis. MNNG sensitive Escherichia coli WP2uvrA and 9-AA sensitive Salmonella typhimurium TA1537 were chosen as the bacterial tester strains. All of the test compounds showed significant antimutagenic activity at various tested concentrations. The inhibition rates ranged from 25.6% (Compound 2 - 1?mM/plate) to 68.2% (Compound 1 - 2.5?mM/plate) for MNNG and from 25.7% (Compound 4 - 1?mM/plate) to 76.1% (Compound 3 - 2.5?mM/plate) for 9-AA genotoxicity. Moreover, the mutagenicity of the test compounds was investigated by using the same strains. None of the test compounds has mutagenic properties on the bacterial strains at the highest concentration of 2.5?mM. Thus, the findings of the present study give valuable clues to develop new strategies for chemical prevention from MNNG and 9-AA genotoxicity by using synthetic indenopyridine derivatives.     

阿比哚致突变作用的研究

目的研究阿比哚的致突变作用。方法应用微生物回复突变试验、小鼠微核试验、哺乳动物培养细胞染色体试验 ,观察阿比哚对细胞的诱变性。结果阿比哚的Ames实验、小鼠体内微核试验、CHL细胞染色体畸变试验均呈阴性结果 ,阿比哚无诱变性。结论阿比哚无致突变作用。     

Effect of weak-, non-, and co-carcinogenic chemicals on 2-acetylaminofluorene-induced mutation in Salmonella typhimurium.

The effects of various weak, non-, and co-carcinogenic chemicals on 2-acetylaminofluorene-induced mutation in Salmonella typhimurium were studied. We found that a single co-mutagen could provide for either enhanced or decreased mutagenesis. A differential effect on mutagenic expression was dependent upon: (1) the type of inducer of S-9 (supernatant from liver homogenate centrifuged at 9000 x g) liver enzymes; (2) the amount of S-9 enzyme preparation employed; and (3) the combined dose of mutagen plus co-mutagen studied. No effect was observed in the absence of S-9. Our data suggest that in S. typhimurium a primary factor in the alteration of mutagenesis by a combination of chemicals is changes in metabolism of the principal mutagen.