Mitochondrial toxicity and in vitro biological effects of ambient PM2.5 from an urban site in China

Abstract

The roles of PM_2.5-induced mitochondrial damage and oxidative stress on mast cell degranulation were examined in vitro. Mast cells were treated with suspensions of PM_2.5 in Dulbecco’s modified Eagle’s medium at concentrations from 25 to 200?mg/L in the absence or presence of 10?mmol/L N-acetyl-L-cysteine. Biological effects and mitochondrial function were assessed by determining cell viability, β-hexosaminidase release, interleukin-4 secretion, reactive oxygen species generation, adenosine triphosphate production, potential alteration of mitochondrial membrane, and activities of mitochondrial electron transport chain complexes I and III. Exposure of mast cells to PM_2.5 induced reduction of adenosine triphosphate production, collapse of mitochondrial membrane potential, and inhibition of the activity of complex III. Co-treatment of mast cells exposed to PM_2.5 with N-acetyl-L-cysteine attenuated cytotoxicity and the production of reactive oxygen species, and decreased the release of β-hexosaminidase and interleukin-4. Evidently, PM_2.5-induced oxidative stress plays an essential role in mitochondrial toxicity and mast cell activation.     

Epigenetic effect of long-term bisphenol A exposure on human breast adenocarcinoma cells

In this research, epigenetic effects of bisphenol A (BPA) on human breast cancer MCF-7 cells were analyzed. Genome-wide DNA methylation and gene expression were analyzed in MCF-7 cells exposed to BPA (10^?5 and 10^?6 mol/L for 5 weeks). No significant changes in the global level of 5-methyl-2′-deoxycytidine and 5-hydroxymethyl-2′-deoxycytidine were observed. DNA methylation profiling analysis indicated that BPA exposure resulted in the hypermethylation of FOXK2, LKB1, LMX1A and CUGBP2 and the hypomethylation of PTPRN2, TRIM27, BCAS3 and ZNF423. Decreased expression of apoptosis genes (P38 and BCL2L1) and increased expression of chemokine (Cxcl2 and ccl20) were detected. Changes of these genes were speculated to affect the ERα-related cell growth as well as cell apoptosis.     

磷酸三苯酯(TPP)和磷酸三(2-氯异丙基)酯(TCPP)诱导人胚肾细胞HEK293凋亡的机制研究

磷系阻燃剂对人体的潜在毒性作用引起了国内外研究者的广泛关注。肾脏是机体重要的排毒器官,若肾脏细胞受损,可能影响肾脏功能的正常发挥。本研究以人胚肾细胞HEK293为研究对象,结合传统毒理学实验,筛选出磷酸三苯酯(TPP)及磷酸三(2-氯异丙基)酯(TCPP)诱导人胚肾细胞HEK293凋亡的关键靶标基因p53。在此基础上采用分子对接模拟和光谱法分析发现,TPP和TCPP分别以嵌插方式和沟槽方式结合p53-DNA,改变基因片段的框架结构,启动分子起始事件,通过影响相关基因(Bax、Hrk、Bcl-2和Bad)的表达量,导致线粒体途径释放cyt c,最终激活Caspase 7实现细胞凋亡。研究结果阐明了此类污染物诱导凋亡的作用机制,为毒害化学品的污染防控提供理论依据。     

连续流双室微生物燃料电池处理工业废水

以实际中药废水作为阳极基质、实际含镉废水作为阴极电解液,构建了连续流双室微生物燃料电池(MFC),考察了其产电性能及对两种废水的处理效果。78 d的运行数据表明:系统可实现最大输出电压417mV、最大体积功率密度11.8 W/m3,最大体积功率密度运行条件下的库伦效率为18.5%;在阳极进水有机物浓度变化较大的情况下,实现了阳极对中药废水中有机物的有效去除,平均COD去除率为81.5%;阴极对含镉废水中Cd2+的去除率为79.4%～84.8%。这表明MFC同步处理中药废水及重金属废水具有一定的可行性。     

Oxidative and genotoxic effects of bisphenol A on primary gill cell culture of Lake Van Fish (Alburnus tarichi Güldenstädt, 1814)

Lake Van is the largest lake in Turkey. The lake limits lifespan due to its high pH and brackish water. For this reason, only a single species of fish (Van Fish) is living in the lake that has been adapted to these conditions. In the present study, we investigated the total oxidant status (TOS), total antioxidant status (TAS), malondialdehyde (MDA) level and DNA damage effect of bisphenol A (BPA) (10^?7, 10^?6 and 10^?5?M) on primary gill cell culture of Van Fish for 24 and 48?h of incubation periods. TAS levels were not changed when compared to those of the control group, but TOS levels were decreased in both 24 and 48?h. The MDA level increased only at the highest concentration (10^?5) at the end of 12 and 24?h (p?.05). DNA damage increased only at the 10^?5?M concentration after 48?h. At the end of the experiment, BPA exposure caused lipid peroxidation and genotoxic effect. These results indicate that high levels of BPA exposure induced oxidative stress and DNA damage by time- and concentration-dependent fashion in the gill cell culture of Van Fish. Gill cell culture is a useful model for the rapid identification of the harmful effects of chemicals in the aquatic environment.     

微生物-光-电化学耦合技术降解污染物和回收能源的研究进展

微生物电化学技术能同时实现污染物去除和能量回收，但存在污染物去除种类有限及产能效率低的局限，近几年将可再生的太阳能引入微生物电化学技术的微生物-光-电化学耦合技术应运而生。本文简要介绍了微生物-光-电化学耦合技术的发展背景和研究现状，对该技术现有的耦合形式进行分类，并对各种形式的耦合机理进行详细的阐释，最后对其未来的发展进行了展望。     

山区和平原连接处SF6试验及扩散规律研究

为更好了解污染物在复杂地形条件下的湍流扩散规律,2010年9月开展了一系列SF6示踪扩散试验,获取了SF6浓度数据,以此实验数据为基础,计算出SF6浓度分布在水平和垂直方向的扩散标准差、地面峰值浓度等参数,并与P-T-C扩散参数进行对比,总结得出了污染物在山区和平原连接处中性、稳定、强稳定等气象条件下湍流扩散规律。     

某涡轮风扇发动机试车台的声环境研究

涡轮风扇发动机试车台空气流量大,试车噪声呈宽带强噪声,其中突出的低频域噪声可远距离传播,易造成大范围的环境污染。为掌握某型涡轮风扇发动机在室内试车时的噪声特性,并检验试车台建筑物和各项降噪设备的效果,我们对新建试车台的声环境进行了测量。通过对该试车台内、外环境噪声数据的分析,表明新建试车台的声环境满足了我国有关规范的要求。本次研究工作对今后试车台的声学设计具有重要的借鉴意义。     

基于半经验模型对大面积染料敏化太阳电池性能影响因素的研究

以影响大面积染料敏化太阳电池性能的几个物理参量和几何参量为切入点,分析了内部电阻对电池性能的影响,针对几种构型不同的大面积电池,建立了效率的半经验模型.根据并联、串联、和各单元独立式串并联的大面积电池的相关物理参量和几何参量,对电池效率进行了计算.通过比较计算值与测试值的偏差,分析了半经验模型的适用性.在半经验模型的基础上,分析了相关物理参量和几何参量对电池性能的影响.结果表明,在实际应用中,通过半经验模型分析物理参量和几何参量的影响,可以优化大面积电池的性能.     

反硝化微生物燃料电池的基础研究

在启动双室型反硝化微生物燃料电池的基础上,研究了阴极溶解氧及外电阻对其产电性能和污染物去除效果的影响.结果表明,以乙酸钠为阳极电子供体,硝酸钠为阴极电子受体,在25℃的环境温度下,采用先间歇后连续培养的方式,42d内成功启动了反硝化微生物燃料电池.在阴极进水含氧的情况下,氧和硝酸盐可共同用作阴极电子受体.在较小电流密度区域内,氧是阴极的主要电子受体,相应的最大功率密度为26.0W/m3NC;电流密度增加到一定程度后,硝酸盐逐步变为阴极的主要电子受体,相应的最大功率密度为20.9W/m3NC.外阻变化对COD去除及反硝化程度影响较小,阳极COD去除负荷维持在1.2kg/(m3NC·d)左右,出水NO-2-N保持在0.05mg/L以下;但外阻减小有利于提高阴极脱氮效果,外阻为5 Ω时NO-3-N去除负荷达0.111kg/(m3NC·d).