本文選題：納米材料　切入點(diǎn)：微核　出處：《南方醫(yī)科大學(xué)》2012年碩士論文　論文類型：學(xué)位論文

【摘要】：納米材料由于尺寸小、結(jié)構(gòu)特殊,具有許多新的理化特性和生物學(xué)特性,在醫(yī)藥、制造業(yè)、日用品、通信和環(huán)境工程等多個(gè)領(lǐng)域具有廣泛的應(yīng)用前景。因此,納米科技被很多國(guó)家列為科技發(fā)展戰(zhàn)略的重中之重。由于納米材料理化性質(zhì)的改變,可能帶來(lái)生物學(xué)效應(yīng)的改變,特別是可能帶來(lái)尚未被人們認(rèn)知的新的生物學(xué)效應(yīng)。由此產(chǎn)生了一個(gè)重要的科學(xué)問(wèn)題,即現(xiàn)行的安全性評(píng)價(jià)方法是否適用于評(píng)價(jià)納米材料的安全性。由于納米科技的快速發(fā)展,納米材料和產(chǎn)品的安全性評(píng)價(jià)已成為迫切需要解決的影響納米科技發(fā)展的瓶頸,也成為當(dāng)前毒理學(xué)研究的前沿和熱點(diǎn)問(wèn)題。 遺傳毒性評(píng)價(jià)是安全性評(píng)價(jià)的重要內(nèi)容之一,國(guó)內(nèi)外對(duì)此也開(kāi)展了不少研究。但由于這些研究著重于納米材料有無(wú)遺傳毒性的測(cè)試和納米尺度等物理特性與遺傳毒性關(guān)系的研究,尚難以回答現(xiàn)行方法是否適用于納米材料遺傳毒性評(píng)價(jià)的問(wèn)題。我們認(rèn)為充分揭示納米材料遺傳毒作用的特征可能是較快回答現(xiàn)行方法是否適用于納米材料評(píng)價(jià)的切入口。 納米材料根據(jù)組成成分和結(jié)構(gòu)的不同,可分為含金屬及其氧化物類、含聚合物類、含復(fù)合物類和含碳類納米材料。為此,本課題擬從四類納米材料中選擇代表物,采用單一細(xì)胞在相同暴露條件下同時(shí)觀察DNA損傷、基因突變和染色體畸變等多個(gè)遺傳毒性終點(diǎn)的研究思路,采用對(duì)納米物質(zhì)與同一常規(guī)尺度物質(zhì)進(jìn)行比較的研究策略。從而較系統(tǒng)地揭示納米材料的遺傳毒作用特征,為我國(guó)確定納米材料遺傳毒性評(píng)價(jià)的決策提供科學(xué)依據(jù)。 目的： 通過(guò)常規(guī)尺度和納米尺度的同種材料進(jìn)行比較研究,揭示納米材料的遺傳毒性特征和可能的遺傳毒作用機(jī)制,為納米材料安全性的決策和評(píng)價(jià)方案的選擇提供依據(jù)。 方法： 以小鼠淋巴瘤細(xì)胞(L5178Y細(xì)胞)作為受試細(xì)胞,采用體外胞質(zhì)分裂阻滯微核細(xì)胞組學(xué)實(shí)驗(yàn)和堿性彗星實(shí)驗(yàn)來(lái)研究常規(guī)尺度和納米尺度物質(zhì)誘導(dǎo)發(fā)生的DNA損傷、染色體斷裂、染色體丟失、染色體重組及基因擴(kuò)增的特征。實(shí)驗(yàn)數(shù)據(jù)以均數(shù)±標(biāo)準(zhǔn)差(X±S)表示,利用SPSS13.0進(jìn)行兩因素析因分析,組間和劑量間兩兩比較采用LSD法。 結(jié)果： 1.納米ZnO在0.5μ.g/ml劑量時(shí)Ⅰ型微核和核芽效應(yīng)與對(duì)照組相比明顯增加(P=0.003,P=0.027),2.5μg/ml劑量時(shí)除Ⅰ型微核和核芽效應(yīng)外,Ⅱ型微核和核質(zhì)橋效應(yīng)與對(duì)照組相比也明顯增加(P=0.001,P=0.012)；而微米ZnO組雖除Ⅰ型微核外其它效應(yīng)有隨劑量增加而上升的趨勢(shì),但與對(duì)照組相比差異均無(wú)統(tǒng)計(jì)學(xué)意義(P=0.694,P=0.058,P=0.074,P=0.438)；納米ZnO在≥0.5μg/ml劑量的Ⅰ型微核、Ⅱ型微核和核芽與同劑量的微米ZnO組比較有統(tǒng)計(jì)學(xué)差異(P0.05)。彗星實(shí)驗(yàn)結(jié)果顯示：納米ZnO在0.5μg/ml劑量時(shí)就可誘導(dǎo)DNA發(fā)生嚴(yán)重?fù)p傷,而微米ZnO在2.5μg/ml劑量時(shí)才產(chǎn)生,從尾部DNA%、尾長(zhǎng)和Olive尾距三項(xiàng)指標(biāo)來(lái)看,納米ZnO在2.5μg/mll劑量時(shí)誘導(dǎo)的數(shù)值遠(yuǎn)大于同劑量的微米ZnO(P=0.015,P=0.008,P=0.001)。 2.納米TiO2在1.56μg/ml劑量時(shí)Ⅰ型微核效應(yīng)與對(duì)照組比明顯增加(P=0.005),3.13μg/ml時(shí)核質(zhì)橋和核芽效應(yīng)與對(duì)照組相比也明顯增加(P=0.015.P=0.031),Ⅱ型微核效應(yīng)在6.25μg/ml劑量時(shí)與對(duì)照組相比明顯增加(P0.001)；微米Ti02在6.25μg/ml劑量時(shí)Ⅰ型微核效應(yīng)與對(duì)照組相比明顯增加(P=0.001),12.5μg/ml時(shí)核質(zhì)橋效應(yīng)與對(duì)照組相比也明顯增加(P=0.015),而Ⅱ型微核和核芽效應(yīng)與對(duì)照組相比無(wú)統(tǒng)計(jì)學(xué)差異(P=0.068,P=0.076)；納米Ti02組的總微核、Ⅰ型微核、Ⅱ型微核和核芽與微米Ti02組比較有統(tǒng)計(jì)學(xué)意義(P=0.014,P=0.005,P=0.010,P=0.031)。彗星實(shí)驗(yàn)結(jié)果顯示：0.78μg/ml劑量組,納米Ti02誘導(dǎo)的尾長(zhǎng)和OTM與對(duì)照組有統(tǒng)計(jì)學(xué)差異(P=0.001,P=0.029),微米TiO2在3.13μg/ml劑量下誘導(dǎo)的尾長(zhǎng)與對(duì)照組有統(tǒng)計(jì)學(xué)差異(P-0.002)。無(wú)論是尾部DNA%,還是尾長(zhǎng),亦或是OTM,納米Ti02誘導(dǎo)的數(shù)值遠(yuǎn)大于同劑量的微米Ti02(P=0.003,P0.001,P0.001)。 3.納米聚苯乙烯組在40μg/ml劑量時(shí)Ⅰ型微核和核質(zhì)橋效應(yīng)與對(duì)照組相比明顯增加(P=0.026,P=0.023),Ⅱ型微核效應(yīng)在80μg/ml劑量與對(duì)照組相比也明顯增加(P=0.008),核芽效應(yīng)在160μg/ml劑量下與對(duì)照組相比也明顯增加(P=0.030)；微米聚苯乙烯在80μg/ml劑量時(shí)Ⅰ型微核和核質(zhì)橋效應(yīng)與對(duì)照組相比明顯增加(P=0.026,P=0.023),Ⅱ型微核效應(yīng)在160μg/ml劑量時(shí)與對(duì)照組相比也明顯增加(P=0.008),而核芽效應(yīng)與對(duì)照組無(wú)統(tǒng)計(jì)學(xué)差異(P=0.093)。彗星實(shí)驗(yàn)結(jié)果顯示：納米聚苯乙烯在20μg/ml劑量下,誘導(dǎo)產(chǎn)生的尾部DNA%、尾長(zhǎng)和OTM與對(duì)照組相比,差異有統(tǒng)計(jì)學(xué)意義(P=0.030,P=0.010,P=0.001),聚苯乙烯誘導(dǎo)的尾部DNA%、尾長(zhǎng)和OTM與對(duì)照組相比,沒(méi)有統(tǒng)計(jì)學(xué)差異(P=0.653,P=0.089,P=0.082)。 4. CdTe/Cds/ZnS630在2.50μg/ml劑量時(shí)Ⅰ型微核、Ⅱ型微核和核芽效應(yīng)與對(duì)照組相比明顯增加(P0.001,P0.001,P=0.010),5.00μg/ml時(shí)核質(zhì)橋效應(yīng)與對(duì)照組相比也明顯增加(P=0.001)；CdTe/Cds/ZnS570在0.63μg/ml劑量時(shí)Ⅰ型微核和核芽效應(yīng)與對(duì)照組相比明顯增加(P=0.042,P=0.001),1.25μg/ml時(shí)Ⅱ型微核和核質(zhì)橋效應(yīng)與對(duì)照組相比也明顯增加(P0.001,P=0.007)。在≥1.25μg/ml劑量時(shí),CdTe/Cds/ZnS570誘導(dǎo)各類損傷的程度大于CdTe/Cds/ZnS630(P=0.001,P0.001,P=0.035,P=0.001)。彗星實(shí)驗(yàn)結(jié)果顯示：在0.63μg/ml劑量下,CdTe/Cds/ZnS630誘導(dǎo)的尾長(zhǎng)與對(duì)照組相比,差異有統(tǒng)計(jì)學(xué)意義(P=0.007),CdTe/Cds/ZnS570誘導(dǎo)的尾部DNA%、尾長(zhǎng)、Olive尾距與對(duì)照組相比都有顯著差異(P0.001,P=0.002,P=0.002),且損傷隨著劑量的增加而加重。 5. SWCNT在40μg/ml劑量時(shí)Ⅰ型微核效應(yīng)與對(duì)照組相比明顯增加(P0.001),80μg/ml時(shí)Ⅱ型微核和核芽效應(yīng)與對(duì)照組相比也明顯增加(P=0.010,P=0.013),160μg/ml時(shí)核質(zhì)橋與對(duì)照組相比有統(tǒng)計(jì)學(xué)差異(P=0.008)；MWCNT在20μg/ml劑量時(shí)Ⅰ型微核和核芽效應(yīng)與對(duì)照組相比明顯增加(P=0.003,P=0.038),40μg/ml時(shí)Ⅱ型微核效應(yīng)與對(duì)照組相比也明顯增加(P=0.024),80μg/ml時(shí)質(zhì)橋效應(yīng)與對(duì)照組相比也有統(tǒng)計(jì)學(xué)差異(P=0.006)；炭黑組Ⅰ型微核、Ⅱ型微核、核質(zhì)橋和核芽效應(yīng)與對(duì)照組相比無(wú)統(tǒng)計(jì)學(xué)差異(P=0.088,P=0.526,P=0.104,P=0.051)。 結(jié)論： 1.含金屬及其氧化物類納米材料ZnO和Ti02與相應(yīng)常規(guī)尺度材料相比,在遺傳毒作用性質(zhì)和強(qiáng)弱上存在差異,納米誘導(dǎo)損傷的程度大于其相應(yīng)的常規(guī)尺度材料。在受試劑量下,都可誘導(dǎo)DNA損傷,納米ZnO和納米TiO2可誘導(dǎo)微核、核質(zhì)橋和核芽效應(yīng),微米ZnO未觀察到這些效應(yīng),微米Ti02可誘導(dǎo)Ⅰ型微核和核質(zhì)橋效應(yīng)。 2.含聚合物類納米聚苯乙烯與常規(guī)尺度聚苯乙烯相比,前者的遺傳毒性大于后者。納米聚苯乙烯在低劑量下可誘導(dǎo)DNA損傷、Ⅰ型微核和核質(zhì)橋效應(yīng),隨著劑量的增高,還可誘導(dǎo)Ⅱ型微核和核芽效應(yīng)；微米聚苯乙烯高劑量下誘導(dǎo)Ⅰ型微核、核質(zhì)橋和Ⅱ型微核效應(yīng),但未觀察到核芽效應(yīng),表明納米與常規(guī)尺度聚苯乙烯在遺傳毒作用性質(zhì)上也存在差異。 3.含復(fù)合物類的CdTe/Cds/ZnS630和CdTe/Cds/ZnS570兩種量子點(diǎn)毒作用性質(zhì)相似,均可誘導(dǎo)細(xì)胞出現(xiàn)Ⅰ型微核、Ⅱ型微核、核質(zhì)橋和核芽效應(yīng),但CdTe/Cds/ZnS570的遺傳毒性大于CdTe/Cds/ZnS630。 4.含碳類的SWCNT、MWCNT與常規(guī)尺度的炭黑顆粒相比,在毒作用性質(zhì)上存在明顯差異,納米管可誘導(dǎo)細(xì)胞出現(xiàn)Ⅰ型微核、Ⅱ型微核、核質(zhì)橋和核芽效應(yīng),炭黑顆粒未觀察到這些效應(yīng),兩種碳納米管遺傳毒作用強(qiáng)弱不同,MWCNT的遺傳毒性較SWCNT強(qiáng),SWCNT在較高劑量下產(chǎn)生毒效應(yīng),而MWCNT在較低劑量下產(chǎn)生。
[Abstract]:Nano materials because of the small size, special structure, it has many new physicochemical and biological characteristics, in manufacturing, medicine, daily necessities, and has wide application prospect in many fields of communication and environmental engineering. Therefore, nano science and technology by many countries as the scientific development strategy of the priority among priorities. Because science the change of properties of nano materials, may bring biological effect change, especially may have not known by us new biological effects. This brings an important scientific problem, safety evaluation method is whether the current suitable for the safety assessment of nanomaterials. Due to the rapid development of nano technology, safety evaluation of nano materials and products has become a bottleneck affecting the development of nano science and technology is urgent needs to solve, also become the frontier and hot issues in the current toxicology research.
Genotoxicity assessment is an important part of safety evaluation at home and abroad, which has been researched a lot. But because of the characteristics of the study focuses on the nano materials have no genetic toxicity test and nano scale physical and genetic toxicity, it is difficult to answer the current method is suitable for the evaluation of genetic toxicity of nano materials. We believe that fully reveal the characteristics of nano materials genetic toxicity may be rapid answer current method is applicable for the evaluation of the entry of nano materials.
Nano materials according to the different compositions and structures, can be divided into metal, containing polymers, containing compound and carbon nano material. Therefore, this paper from four kinds of nano materials choice, using a single cell under the same exposure conditions and observe DNA damage, research ideas gene mutation and chromosome aberration of multiple genetic toxicity end point, using the comparative study method of nano material with the same material. Thus the conventional scale systematically reveal the characteristics of genetic toxicity of nano materials, nano materials for our evaluation to determine the genetic toxicity of decision-making to provide a scientific basis.
Objective:
Through comparative study of the same scale and nano scale materials, the genotoxic characteristics and possible mechanisms of genetic toxicity of nanomaterials will be revealed, which will provide a basis for the decision-making and evaluation of nanomaterials safety.
Method錛，

本文編號(hào)：1617614