Application of γH2AX assay in measurement of DNA double stand breaks

dnA双链断裂(dSbS)是真核细胞dnA损伤最严重的形式,dnA损伤反应的激活可以导致基因组的不稳定,从而引发肿瘤;H2AX磷酸化产生的γH2AX作为一种生物标志物可以清楚地反映dnA损伤程度和修复情况,被国内外广泛应用于细胞凋亡研究中,是细胞损伤应激反应的研究热点之一;本文对γH2AX用作dSbS检测的研究进展做一综述,对其在化合物的遗传毒性评估与临床肿瘤的早期筛查及治疗效果评价进行展望。DNA double strand breaks( DSBs) are the gravest form of DNA damage in eukaryotic cells and it is a serious lesion that can cause genomic instability,ultimately leading to tumorigenesis.Phosphorylated histone H2AX( γH2AX) is a biomarker of cellular response to DSBs and could clearly reflect the status of DNA damage and repair and the biomarker is widely applied in the researches of cell apoptosis both in domestic and abroad.The reviewfocuses on the research progress in the application of γH2AX-based methods to detect DNA DSBs,as well as application in early cancer screenings,assessment on the genotoxicity of environmental compounds,and evaluation of therapeutic effect of medical procedures or treatments.福建省自然基金(2013J01354); 厦门市科技计划项目(3502Z30123003

Effects of benzo[a]pyrene and DDT subacute co-exposure on ALT, AST and γ-GT in mice

目的:探讨不同剂量的苯并[A]芘(b[A]P)和滴滴涕(ddT)联合暴露对小鼠血清中谷丙转氨酶(AlT)、谷草转氨酶(AST)和γ-谷胺酰转移酶(γ-gT)的影响及作用形式。方法:成年雄性昆明种小鼠50只,随机分为10组即空白对照组(正常饲养)、溶剂对照组(食用油和二甲基亚砜处理)、低和高浓度b[A]P染毒组[1.0和10 Mg/(kg·d)]、低和高浓度ddT染毒组[0.6和6 Mg/(kg·d)]、低浓度ddT+低浓度b[A]P染毒组、低浓度ddT+高浓度b[A]P染毒组、高浓度ddT+低浓度b[A]P染毒组、高浓度ddT+高浓度b[A]P染毒组。染毒组各受试物经腹腔注射染毒,每日注射1次,连续31 d。末次染毒24 H后通过眼球摘除取血,自动生化仪检测血清中AlT、AST、γ-gT的活性;并制作肝脏HE切片,观察肝细胞形态。采用两因素三水平析因设计的方差分析对数据进行统计分析。结果:与对照组比较,b[A]P和ddT单独染毒时,均能诱导AlT和AST活性升高(f=41.308,P=0.000;f=20.083,P=0.000),随各自染毒剂量的增加,AlT和AST活性升高,但二者联合暴露对AlT和AST活性均不存在交互作用(分别为P=0.258,P=0.264)。b[A]P和ddT单独染毒对γ-gT活性均未产生明显影响,联合暴露也不存在交互作用(P=0.816)。HE染色观察到肝细胞膜界限模糊,发生水样变性,肝细胞中出现小空泡,呈蜂窝状,随染毒剂量增加,肝细胞质水样变性加剧,部分肝细胞质溶解,并且细胞核肿大,形状不规则。结论:在本实验条件下,b[A]P和ddT单独染毒均能诱导小鼠血清AlT和AST活性升高,不同剂量的b[A]P和ddT联合暴露对小鼠血清AlT、AST活性的作用形式主要表现为单独作用,而非交互作用。b[A]P和ddT的单独和联合暴露均未观察到对γ-gT的活性产生明显影响。OBJECTIVE: To explore the effects of benzo[a] pyrene and DDT exposure alone or in combination on ALT,AST and γ-GT in mice.METHODS:Fifty healthy male Kunming mice were divided into 10 groups at random:blank control group(normal feed);solvent control group(equal volume of oil);1,10 mg/(kg·d) B[a]P groups;0.6,6 mg/(kg·d) DDT groups;1 mg/(kg·d) B[a]P+0.6 mg/(kg·d) DDT group;1 mg/(kg·d) B[a]P+6 mg/(kg·d) DDT group;10 mg/(kg·d) B[a]P+0.6 mg/(kg·d) DDT group and 10 mg/(kg·d) B[a]P+6 mg/(kg·d) DDT group.Exposure groups were treated with oil contained B[a]P and DDT once a day.After 31 days of intraperitoneal injection,eyeballs were extracted and ALT,AST and γ-GT were examined in blood.HE slices were made to confirm the liver damage.Using two factors and three levels factorial ANOVA design for data analysis.RESULTS:The levels of ALT and AST in all B[a]P or DDT alone exposure groups were significantly higher than that of the control groups(F=41.308,P=0.000;F=20.083,P=0.000),showing dose-effect relationships in both.But no interaction was observed in co-exposure groups(P=0.258,P=0.264).No significant changes in γ-GT were observed in all B[a]P or DDT alone exposure groups.Neither was there any interactive effect in co-exposure groups(P=0.816).This was in accordance with the observation in HE slice:hydropic degeneration,endolysis and nuclear enlargement in liver cell.CONCLUSION:Under this experimental condition,increasing levels of ALT and AST could be detected in B[a]P or DDT separate exposure groups.But neither could affect γ-GT level.No interactive effects of ALT,AST and γ-GT could be induced in co-exposure groups.福建省自然科学基金项目(2013J01354); 厦门市科技计划项目(3502Z20123003); 中央高校基本科研业务费专项资金(2011121006

Preliminary exploration of the experiments teaching reform on water quality monitoring and evaluation course for preventive medicine majors

水质监测与评价是预防医学专业实验教学的重要组成部分,熟悉并掌握水质监测与评价的方法与流程,对于本专业学生毕业后从事疾病预防控制、卫生监督等工作具有举足轻重的作用。针对目前国内水质监测与评价实验教学中存在的问题,通过增加现场教学环节、拓展实验教学内容以及强化实验教学管理与分析质量控制等改革措施,将实验教学与校园环境监测紧密结合起来,以激发学生学习的积极性和主动性,培养学生独立思考问题、分析问题和解决问题的能力,进而为全面提高实验教学质量进行了有益的探索与尝试。Water quality monitoring and evaluation is an important part of experimental teaching for preventive medicine majors.Familiarizing with and mastering the methods and procedures of water quality monitoring and evaluation is crucial for students engaging in disease prevention and control or health supervision after graduation.Aiming at solving the existing problems in experimental teaching of water quality monitoring and evaluation, a series of reformative measures, including increasing the frequency of field experimental teaching, expanding the contents of experimental teaching, strengthening the management of experimental teaching, and analyzing quality control, were implemented; and experiment teaching was combined with monitoring of the campus environment.These measures aimed to stimulate students' initiative to learn, cultivate students' independent thinking and problem analyzing and solving skills, and therefore provide useful exploration and trials in comprehensively improving the quality of experimental teaching

Progress research on degradation of decabromodiphenyl ether by microorganisms

本文综述了国内外十溴联苯醚微生物降解的研究进展,主要包括微生物好氧降解、微生物厌氧降解、零价铁-微生物降解和光-微生物降解。在此基础上,提出十溴联苯醚微生物降解研究中存在的问题,并对十溴联苯醚微生物处理方法的相关研究进行展望。中央高校基本科研业务费专项资金资助课题(2011121006); 国家级大学生创新创业训练计划项目资助课题(201210384167); 福建省厦门市科技局科技计划项目资助课题(3502Z20123003

双酚A联合己烯雌酚对未成年雌性SD大鼠的雌激素效应

目的:探讨双酚A(BPA)和己烯雌酚(DES)单独和联合作用于未成年雌性SD大鼠后的雌激素效应,为进一步阐明环境雌激素(EEs)的危害机制提供依据。方法:未成年雌性SD大鼠(21d),分为BPA(200、400和800 mg·kg-1)组,DES(15和150μg·kg-1)组和BPA+DES(100 mg·kg-1 BPA+7.5μg·kg-1 DES,200mg·kg-1 BPA+7.5μg·kg-1 DES,400 mg·kg-1 BPA+7.5μg·kg-1 DES,400mg·kg-1 BPA+75.0μg·kg-1 DES)联合组,同时设对照组;观察各组大鼠子宫湿质量、子宫/体质量比、子宫腔内膜上皮高度、宫腔平滑肌厚度、宫腔腺体数量和成熟卵泡数量。结果:800mg·kg-1 BPA组大鼠子宫湿质量、子宫/体质量比、子宫腔内膜上皮高度、宫腔平滑肌厚度和宫腔腺体数量较对照组明显增加(P0.05)。结论:BPA和DES在单独作用时均具有雌激素活性,BPA联合DES的雌激素效应表现为相加作用。福建省教育厅中青年教师教育科研项目资助课题(JAT160582);;福建省厦门市科技计划项目资助课题(3502Z20159004);;厦门医学院博士基金资助课题(K2016-11

The diversity changes of bacterial community in mariculture water of Litopenasus vannamei at Zhangpu,Fujian Province

为分析凡纳滨对虾(Litopenaeus; vannamei)海水养殖过程中水体细菌群落多样性变化,本研究采用Illumina测序技术对福建漳浦县凡纳滨对虾海水养殖中后期水体样品进行16S; rRNA基因高通量测序,同时进行水质参数测定。结果表明,养殖过程中,氨氮(NH_4~+; -N)、化学需氧量(COD)值波动较大,其他水质参数值波动较小。检测到的细菌种群归属于19个门、35个纲、80个目、135个科、254个属,说明; 该养殖水体中细菌群落具有高度的多样性。变形菌门和拟杆菌门是养殖期间主要优势类群,不同养殖时期细菌组成存在一定的波动,但没有明显的变化规律。蓝细菌; 在第67天、115天表现出高丰度,且其丰度在养殖期间变化较大(比例变化为0.7%~63.9%)。此外,益生菌和潜在致病菌丰度在养殖期间很低。冗余; 分析(Redundancy analysis,RDA)表明,对细菌群落影响最大的水质因子是化学需氧量与硝酸盐浓度比值(COD/NO_3~-; )和COD;降低溶氧可以增加细菌丰富度。总之,本研究初步揭示了对虾养殖中后期水体微生物的演替规律,发现水质因子对养殖水体微生物组成具有显著影响,; 研究结果为凡纳滨对虾健康养殖提供一定的参考意义。To explore the diversity changes of bacterial communities in mariculture; water,water samples from Litopenasus vannamei culture ponds in the; middle and late growth stages at the farms located at Zhangpu,Fujian; Province,China,were collected.Bacterial communities were analyzed; through Illumina Miseq sequencing based on 16SrRNA gene,and the water; quality parameters were also detected.The results showed that the water; quality factors,such as NH_4~+ -N,COD,fluctuated greatly compared with; other parameters.19phyla,35classes,80orders, 135families and; 254bacterial genera were detected,which indicated a high diversity of; microbial flora.Proteobacteriaand Bacteroidetes are the main dominant; group during culture,and while there was a certain fluctuation of; microbial composition in different aquaculture periods,no obvious change; law was observed.Cyanobacteria showed high abundance at the day of 67and; 115,and their abundance varied greatly during culture(0.7%to 63.9%).In; addition,the abundance of probiotics and potential pathogens is low; during culture.The RDA results showed that COD/NO_3~- and COD contents; in water had the greatest influence on bacterial communities,and reduced; DO can increase bacterial richness.This study revealed the change of; bacterial community in the middle and late stages of L.vannamei; culture,and found that water quality factors had a significant effect on; microbial composition. The results provided a significant reference for; the healthy aquaculture of L.vannamei.厦门南方海洋研究中心项目; 深远海(极地)微生物及其基因资源开发与产品应用示范; 国家自然科学基金项

苯并(a)芘和滴滴涕联合暴露对小鼠肝脏细胞凋亡的影响

目的:探讨不同剂量苯并(a)芘[benzo(a)pyrene,B(a)P]、滴滴涕(chlorophenothane,DDT)单独及联合暴露对小鼠肝脏细胞的毒性效应。方法:成年雌性昆明种小鼠66只,随机分为11组:分别为0.5、5、50mg/(kg·d)B(a)P染毒组,0.025、0.25、2.5mg/(kg·d)DDT染毒组,0.5mg/(kg·d)B(a)P+0.025mg/(kg·d)DDT联合染毒组,5mg/(kg·d)B(a)P+0.25mg/(kg·d)DDT联合染毒组,50mg/(kg·d)B(a)P+2.5mg/(kg·d)DDT联合染毒组,空白对照组(正常饲养)和溶剂对照组(植物油处理)。染毒组用含B(a)P、DDT的食用油进行腹腔注射,每天1次,连续21d,于末次给药24h后处死小鼠。取肝脏制作冰冻切片,利用原位缺口未端标记(terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling,TUNEL)法检测肝细胞凋亡情况。结果:5和50mg/(kg·d)B(a)P染毒组小鼠肝脏细胞凋亡率显著高于对照组(P0.05);各浓度联合染毒组小鼠肝脏细胞凋亡率均高于对照组(P0.05),联合染毒组细胞凋亡率和相应的B(a)P染毒组比较,差异无统计学意义(P>0.05)。结论:B(a)P的单独暴露以及与DDT的联合暴露均可导致小鼠肝脏细胞凋亡的发生,并可能引发其他毒性效应

硼砂与尿素在N_2气氛下合成六方氮化硼的工艺

以硼砂、尿素为原料,采用改进的硼砂-尿素法,在N2气氛下合成六方氮化硼(h-BN),考察了焙烧温度、保温时间、硼砂与尿素摩尔比对氮化硼产率、纯度及形貌的影响,对产品进行了表征.结果表明,合成六方氮化硼的最佳工艺条件为:硼砂/尿素摩尔比1:4、焙烧温度1 300℃、保温时间4 h.该条件下氮化硼产率约为47%,纯度达98%,单片直径300~500 nm,粒度约为4&mu;m,比表面积约为13 m2/g.</p

金属离子和小分子物质对耐铬(Ⅵ)菌株M52还原能力的影响

目的:研究从厦门近岸海域沉积物样品中分离筛选出的芽孢八叠球菌属菌株Sporosarcina saromensis M52在含不同浓度六价铬[Cr（Ⅵ）]培养基中的生长情况,定位Cr（Ⅵ）还原酶,探讨金属离子和小分子物质对耐Cr（Ⅵ）菌株M52还原能力的影响。方法:将M52菌株的种子液接种于含不同浓度(0～600mg·L-1)Cr（Ⅵ）LB培养基中,培养0～48h后用紫外分光光度法测量600nm处M52菌液的吸光度（A）值,观察M52菌株在含0、50、100、200、400和600mg·L-1 Cr（Ⅵ）的LB培养基中的生长情况。将M52菌液超声破碎前、破碎后后离心所得胞内和胞外活性物质与对照组M52菌液在37℃、pH 7.5条件下培养0、12、24和48h,用二苯碳酰二肼分光光度法分别测定溶液中Cr（Ⅵ）的浓度,计算各时间点胞内和胞外活性物质中Cr（Ⅵ）的还原率。在LB培养基中分别加入0.2 mmol·L-1的Mn2+、Fe2+和Cu2+,1 mmol·L-1 SDS、1%Triton X-100和吐温80作为处理组,以未作处理的LB液体培养基为对照组,将种子液以4%浓度接种于处理组和对照组,计算M52菌株在0、6、12、24、36和48h对Cr（Ⅵ）的还原率,分析金属离子和小分子物质处理组中M52菌株对Cr（Ⅵ）还原率的变化。结果:当Cr（Ⅵ）浓度低于100mg·L-1时,随浓度增加菌株生长加快;当100mg·L-1≤Cr（Ⅵ）浓度Fe2+,Mn2+存在情况下M52菌株对Cr（Ⅵ）的还原率降低（PTriton X-100>吐温80。结论:低浓度Cr（Ⅵ）可以促进M52菌株生长,高浓度Cr（Ⅵ）则会抑制菌株生长,M52菌株对Cr（Ⅵ）的还原主要发生在胞内,Cu2+和Fe2+可促进M52菌株还原Cr（Ⅵ）,吐温80、Triton X-100和SDS可抑制M52菌株还原Cr（Ⅵ）。国家自然科学基金面上项目资助课题(81673129)福建省教育厅中青年教师教育科研项目资助课题(JAT160001)厦门大学大学生创新创业训练计划项目资助课题(2016Y0070

硼砂与尿素合成六方氮化硼的机理

研究了N_2气氛下硼砂与尿素反应生成六方氮化硼以及主要副产物产生和变化的过程,采用热重-差示扫描量热法(TG-DSC)、X射线衍射(XRD)、扫描电子显微镜(SEM)等检测手段对反应产物和氮化硼样品进行了分析.研究结果表明,氮化硼在700℃左右完全生成,随焙烧温度的提高其结晶度不断提高.反应副产物偏硼酸钠的生成是导致氮化硼产率较低的主要原因,在高温焙烧过程中偏硼酸钠的存在有利于六方氮化硼的结晶过程.研究结果可为硼砂-尿素法六方氮化硼制备工艺的优化和改进提供理论基础.</p