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81.
Kammann U Lang T Berkau AJ Klempt M 《Environmental science and pollution research international》2008,15(7):600-605
BACKGROUND, AIM, AND SCOPE: Gene expression analyses with real-time (RT)-polymerase chain reaction (PCR) gains importance in marine monitoring. This new technique has to be compared to the classical approaches like the well known biomarker ethoxyresorufin-O-deethylase (EROD) to test their suitability for monitoring programmes. The goal of the present study is to compare EROD activity and CYP1A1 mRNA expression in the important monitoring fish species dab (Limanda limanda) and to answer the question of whether these parameters reflect the polycyclic aromatic hydrocarbon (PAH) contamination of the fish. Further on, glyceraldehyd-3-phosphate dehydrogenase (GAPDH) was investigated as a potential housekeeping gene. MATERIALS AND METHODS: Female dab were caught in the summer of 2004 in the North Sea and in the Baltic. EROD activity was determined in liver samples by a kinetic fluorimetric assay according to a standard protocol. The gene expression of CYP1A (cytochrome P450 1A) and GAPDH were determined by means of RT-PCR. Results were compared to gonado somatic index and to the concentration of PAH metabolite 1OHPyr (1-hydroxypyrene) analysed in the bile fluids of the fish, respectively. RESULTS: Dab from all stations showed a considerable individual variation in the levels of both CYP1A mRNA and EROD. Highest mean values for CYP1A mRNA and EROD were detected in the northern part of the sampling area. In contrast, the PAH metabolite 1OHPyr was found at the highest concentration in fish caught near the German coast. CYP1A mRNA and EROD showed only a minor but significant correlation (r = 0.32, p < 0.05, n = 123). 1OHPyr in bile correlated significantly (p < 0.05) with the amount of GAPDH mRNA content in the liver. DISCUSSION: The significant but low correlation of CYP1A mRNA and EROD activity on an individual basis illustrates that these two parameters are apparently not closely linked. However, maximum EROD values correspond with maximum CYP1A mRNA concentrations when station means are regarded. Because EROD and CYP1A mRNA in dab follow different physiological principles, their application will lead to related but not identical monitoring results. This should be taken into account when future marine monitoring programmes are designed. The results also indicate that PAH are not the crucial factor for CYP1A and EROD levels in dab from the off-shore areas in the North Sea. This is remarkable because the PAH metabolism is known to be CYP1A-dependent and the widely used biomarker EROD has been recommended for monitoring PAH-related effects in fish from the North Sea. Due to a correlation between GAPDH and 1OHPyr, GAPDH was not suitable as housekeeping gene for dab. CONCLUSIONS: Neither the results from EROD nor from CYP1A1 mRNA measurements in dab reflected their exposure to PAH as measured by the PAH metabolite 1OHPyr. Thus, the question arises of whether EROD or CYP1A mRNA is a suitable biomarker at all to indicate PAH exposure in dab from the open North Sea. RECOMMENDATIONS AND PERSPECTIVES: For future biological effect monitoring, it is advisable to measure more and predominately independent parameters by RT-PCR and to incorporate more components of the detoxification system. 相似文献
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长江中游沿江地区具有特殊的战略地位,其产业带建设又面临上海浦东开发和三峡工程建设两大契机。必须扩大对外开放,建设开放型产业带;加快改革步伐,建立社会主义市场经济体系;以资源优化配置,促进长江产业带整体效益的提高;必须协调资源、环境与产业带建设的关系,加强基础产业,调整加工制造业,合理布局生产,实现持续发展。 相似文献
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结合东北制药总厂8座深井曝气装置多年来的运行情况,将气提式深井曝气的理论计算作了较为详尽的推导,得出了井深,井径,曝气深度等参数之间的关系式. 相似文献
89.
松花江水中23种有机污染物的迁移转化研究——应用野外实验池方法 总被引:2,自引:0,他引:2
应用野外实验池实测及模式模拟等实验与计算方法对松花江水中23种有机污染物的迁移转化行为进行了模拟研究,应用3个小型野外池于江边现场,经73h,3个不同实验条件的同时测定,得到各池条件下,每一化合物表观总一级动力学常数,由之估算了挥发性有机物的挥发速率常数,硝基芳烃的光解速率常数,建立了适于实验池及河流的箱式模型,应用箱式模型及所得上述参数,数学模拟了污染物在实验池及江水中变化规律,得到现实际符合的 相似文献
90.
考察中高温热处理对含氮沥青基活性碳纤维[PACF(NH3)]脱除SO2的能力的影响结果表明,在900—1100℃尤其是在1000℃下热处理可显著提高PACF(NH3)脱除SO2的能力.当在30℃下模拟烟气中SO2、O2和H2O的浓度分别为0.002ml/ml、0.1ml/ml和0.1ml/ml,气体流动速率为100ml/min时,0.25g的3种不同比表面积的PACF(NH3)完全除去SO2的时间分别从热处理前的0.25h、1h和1h延长到热处理后的1h、2h和3.5h,SO2穿透后的稳态浓度从热处理前的73%、54%和38%下降到热处理后的32%、24%和10%.脱硫活性的提高主要是由于热处理增强了PACF(NH3)对SO2和O2的吸附作用,加速了SO2的氧化反应. 相似文献