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441.
442.
Ting T. Liao Ru W. Jia Xiao H. Fu Hong Chua 《Journal of environmental science and health. Part. B》2013,48(10):760-768
Membrane damage related to morphological change in Vero cells is a sensitive index of the composite biotoxicity of trace lipophilic chemicals. However, judging whether the morphological change in Vero cells happens and its ratio are difficult because it is not a quantitative characteristic. To find biomarkers of cell morphological change for quantitatively representing the ratio of morphological changed cell, the mechanism of cell membrane damage driven by typical lipophilic chemicals, such as trichlorophenol (TCP) and perfluorooctanesulphonate (PFOS), was explored. The ratio of morphologically changed cells generally increased with increased TCP or PFOS concentrations, and the level of four major components of phospholipids varied with concentrations of TCP or PFOS, but only the ratio of phosphatidylcholine (PC)/phosphatidylethanolamine (PE) decreased regularly as TCP or PFOS concentrations increased. Analysis of membrane proteins showed that the level of vimentin in normal cell membranes is high, while it decreases or vanishes after TCP exposure. These variations in phospholipid and membrane protein components may result in membrane leakage and variation in rigid structure, which leads to changes in cell morphology. Therefore, the ratio of PC/PE and amount of vimentin may be potential biomarkers for representing the ratio of morphological changed Vero cell introduced by trace lipophilic compounds, thus their composite bio-toxicity. 相似文献
443.
Yiting Chen Jun Yan Mengli Chen Fucheng Guo Tao Liu Yi Chen 《Frontiers of Environmental Science & Engineering》2022,16(12):157
444.
为研究不同实验室藻密度监测数据的可靠性,现场采集了藻密度样品,处理为现场平行样和实验室前处理后平行样2种,分别由5家实验室的6名技术人员开展检测分析。参考相关技术规范要求,结合其他领域相似工作的成功应用案例,采用Z比分数法对分析结果开展藻密度实验室间比对。结果表明,数据的相对偏差均符合技术规范要求;对藻密度进行数据直接比对和对数转换后比对,各实验室对现场平行样和实验室前处理后平行样的检测结果均为合格;分析方法原理导致藻密度手工监测的绝对数值偏差较大,对当前的太湖水华预警工作适用性不高。 相似文献
445.
蓝藻暴发引发的水华造成了严重的生态灾难和健康危害,蓝藻水华污染因其已成为全球性的环境问题而受到关注。蓝藻产生的藻毒素具有潜在致癌作用,与多种消化道肿瘤的发病率升高相关,其毒理学效应及其健康危害性更是学术界研究和关注的热点。水华蓝藻细胞提取物较之纯藻毒素的毒理学效应有很大不同,研究水华蓝藻细胞提取物对哺乳动物的毒理学效应能为蓝藻水华的健康风险评估提供一定的理论依据。水华蓝藻细胞提取物对实验鼠产生的毒理学效应,如脏器细胞凋亡和对各脏器抗氧化酶防御系统的损害;水华蓝藻细胞提取物对实验鼠遗传毒性和促癌或致癌作用研究是目前研究的热点和难点问题。 相似文献
446.
Perennial monoculture forming grasses are very important natural remediators of pollutants. Their genetic improvement is an important task because introduction of key transgenes can dramatically improve their remediation potential. Transfer of key genes for mercury phytoremediation into the salt marsh cordgrass (Spartina alterniflora) is reported here. S. alterniflora plays an important role in the salt marsh by cycling of␣elements, both nutrients and pollutants, protects the coastline from erosion, is a keystone species in the␣salt marsh supporting a large food web, which in turn supports a significant segment of economy, including tourism, has an impact on cloud formation and consequently on global weather, and is thus an ecologically important species relevant for our life-support systems. Embryogenic callus of S. alterniflora was co-inoculated with a pair of Agrobacterium strains LBA4404 carrying the organomercurial lyase (merB) and mercuric reductase (merA) genes, respectively, in order to co-introduce both the merA and the merB genes. Seven stable geneticin resistant lines were recovered. The presence of merA and merB genes was verified by PCR and Southern blotting. All but one transgenic lines contained both the merA and the merB sequences proving that co-introduction into Spartina of two genes from separate Agrobacterium strains is feasible and frequent, although the overall frequency of transformation is low. Northern blotting showed differences in relative expression of the two transgenes among individual transformants. The steady-state RNA levels appeared to correlate with the phenotype. Line #7 showed the highest resistance to HgCl2 (up to 500 μM), whereas line #3 was the most resistant to phenylmercuric acetate (PMA). Wild-type (WT) callus is sensitive to PMA at 50 μM and to HgCl2 at 225 μM. 相似文献
447.
利用红外光谱仪记录并分析了36株根瘤菌全细胞组分的红外光谱图,所得图谱分辨率高、重现性好,菌株之间的光谱特征和吸收带的位置、强度各不相同。尤其在指纹区(1700-650cm^-1),不同菌株的图谱有较为明显的差别,利用红外光谱技术可以进行根瘤菌的鉴别,菌株水平的差异能充分表现出来,红外光谱分析在一定程度上可反映根瘤菌的分类地位,但实际应用起来,仍有一定的困难。 相似文献
448.
449.
Spinal muscular atrophy (SMA) preimplantation genetic diagnosis (PGD) has been available since 1998. Protocols are based on the detection of the homozygous deletion of exon 7, which are present in 90–98% of SMA patients. A couple where the woman was a heterozygous carrier of the usual SMN1 Del7 mutation and the man was a heterozygous carrier of pMet263Arg substitution in exon 6 of SMN1 gene was referred for PGD. The usual PGD test being unsuitable for this couple, we developed a novel duplex polymerase chain reaction (PCR)-based PGD test for the detection of the mutation pMet263Arg by allele specific amplification, combined with the amplification of D5S641 extragenic polymorphic marker. PCR conditions were established using single control lymphoblasts and lymphocytes from the pMet263Arg substitution carrier. Amplification was obtained in 100% of the 86 single cells tested, amplification refractory mutation system (ARMS) PCR was specific in 100% of single cells tested and a complete genotype (mutation plus D5S641) was achieved in 88% of them. A PGD cycle was performed successfully and a pregnancy was obtained. An unaffected girl was born and postnatal diagnosis confirmed PGD results. This is the first PGD described for SMA because of another mutation than the major homozygous exon 7 deletion of SMN1. In the future, a similar strategy could be adopted for other subtle mutations of this gene. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
450.
Haemoglobinopathies including α- and β-thalassaemia are the world's most common class of single gene disorder. Prenatal diagnosis (PND) for β-thalassaemia has been proven to be an effective strategy for controlling the incidence of new cases and is widely used in several countries where the disease is common. Successful preimplantation genetic diagnosis (PGD) protocols for β-thalassaemia have been introduced using restriction fragment length polymorphism (RFLP), single-stranded conformation polymorphism (SSCP) and denaturing gradient gel electrophoresis (DGGE). However, contamination and allele dropout (ADO) remain an important concern for all of these strategies. In the present study two PGD protocols for detecting β-thalassaemia mutations (codon 41-42 and IVSI-110) and one for α-thalassaemia (SEA mutation) have been designed and tested. These methods contain failsafe mechanisms to reduce the risk of misdiagnosis due to ADO or contamination and utilise multiplex fluorescent PCR (F-PCR). Interestingly, amplification efficiency and ADO were significantly affected by the choice of DNA polymerase and the freshness of the single cells used. The close similarity between the DNA sequences of β-globin and δ-globin was also found to be an important issue that necessitated careful design of primers for the β-globin gene. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献