共查询到20条相似文献,搜索用时 15 毫秒
1.
Hongqi Wang Ruhan Jiang Dekang Kong Zili Liu Xiaoxiong Wu Jie Xu Yi Li 《Frontiers of Environmental Science & Engineering》2020,14(1):9
2.
De Cian M.-C. Andersen A. Toullec J.-Y. Biegala I. Caprais J.-C. Shillito B. Lallier F. 《Marine Biology》2003,142(1):141-151
The hydrothermal-vent tubeworm Riftia pachyptila relies entirely on its intracellular chemoautotrophic symbionts to sustain its metabolism. The host must therefore provide them with inorganic metabolites, including carbon. This study describes a tool for studying cell processes occurring in a bacteria-containing cell by the dissociation of trophosome cell types. The physiological assays performed on cell preparations focused on carbon dioxide conversion and transport processes. Trophosome tissue was mechanically dissociated, resulting in cell suspensions enriched in small (7-20 µm) bacteriocytes, which were viable for several hours. In addition, medium-term cell cultures were also attempted. As a start to the understanding of the CO2 metabolism of these cells, we were interested in evidence of carbonic anhydrase (CA) isoforms, ATPases and chloride exchangers. Variations in intracellular and extracellular pH, and in intracellular concentrations of sodium, potassium and chloride, were followed after addition of selective inhibitors. The data presented here suggest the occurrence of potential cytosolic and membrane-associated carbonic anhydrase isoforms in the bacteriocytes, proton-driven sodium-ATPases and a well represented anion transporter exchanging intracellular chloride against extracellular anions. 相似文献
3.
红壤胶体铁氧化物界面有机氯的非生物转化研究进展 总被引:7,自引:0,他引:7
综述了红壤胶体铁氧化物的结构、形态及其转化;铁氧化物界面有机氯的非生物转化过程及其影响因素;异化铁还原作用下的有机氯转化过程。有机氯的非生物转化主要包括氧化转化与脱氯转化过程。氧化转化包括暗态下的化学氧化与光化学氧化过程;脱氯转化包括脱氢卤化、加氢脱氯、脱双卤、二聚脱氯与亲核置换脱氯等反应过程。有机氯的非生物转化主要受胶体界面pH、Eh、水溶性有机物、金属离子、铁氧化物形态与铁还原细菌等的显著影响。有机氯非生物转化的化学-微生物耦合机制、复合污染条件下重金属对界面有机氯非生物转化过程的影响机制、红壤胶体界面有机氯污染的综合调控技术方法等三个方面值得关注,有助于推动土壤胶体界面环境化学的发展。 相似文献
4.
5.
甲状腺激素(thyroid hormones,THs)对生物体细胞的正常发育和分化至关重要,甲状腺激素失调可引起中枢神经系统、肺、心血管和其他器官的异常发育。研究表明,环境中的卤代有机污染物(halogenated organic contaminants,HOCs)及其代谢产物具有甲状腺激素干扰效应。抑制参与THs代谢的生物酶,例如磺基转移酶(sulfotransferases,SULTs)和脱碘酶(deiodinases,DIs),是HOCs及其代谢产物干扰THs正常功能的重要方式。本文重点综述了HOCs对不同甲状腺激素代谢酶的抑制效应的研究,讨论了环境计算化学和预测毒理学方法在该领域的重要应用,期望为HOCs干扰甲状腺激素酶代谢活性的深入研究提供借鉴与参考。 相似文献
6.
Jingyang Luo Shiyu Fang Wenxuan Huang Feng Wang Le Zhang Fang Fang Jiashun Cao Yang Wu Dongbo Wang 《Frontiers of Environmental Science & Engineering》2022,16(8):106
7.
污染物对鱼类的甲状腺激素干扰效应及其作用机制 总被引:1,自引:0,他引:1
环境中可以影响生物体甲状腺激素合成、运输、作用和代谢等过程的化学污染物称为甲状腺激素干扰物(TDCs),TDCs被认为是继环境雌激素之后最重要的一类内分泌干扰物.鱼类甲状腺的结构、甲状腺激素的转运和功能等与哺乳动物有较大差别.与哺乳动物相比,污染物干扰鱼类甲状腺激素的研究还较为缺乏.在介绍鱼类甲状腺结构、功能以及甲状腺激素在鱼体内动态过程的基础上,分析了污染物对鱼类的甲状腺激素干扰效应及其作用机制,探讨了今后鱼类甲状腺激素干扰研究的主要方向.污染物能对鱼类甲状腺激素水平、相关酶活性及甲状腺结构等产生直接影响;同时,污染物还可以通过干扰鱼类甲状腺系统对由甲状腺激素调节的重要生理过程如生长、繁殖和发育等产生间接影响.污染物主要通过干扰鱼类甲状腺激素的合成与分泌、转运、清除以及与甲状腺激素受体(TR)的相互作用等机制对鱼类产生不利影响.在污染物对鱼类甲状腺激素干扰的研究中,今后应重点关注环境中"新型"卤化有机污染物、鱼类早期发育过程与甲状腺激素干扰效应的关系、TR介导机制以及TDCs的筛选方法等. 相似文献
8.
Alice Barbaglio Daniela Mozzi Michela Sugni Paolo Tremolada Francesco Bonasoro Ramon Lavado Cinta Porte M. Daniela Candia Carnevali 《Marine Biology》2006,149(1):65-77
Regenerative phenomena reproduce developmental processes in adult organisms and are regulated by neuro-endocrine mechanisms.
They can therefore provide sensitive tests for monitoring the effects of exposure to endocrine disrupter contaminants (EDs)
which can be bioaccumulated by the organisms causing dysfunctions in steroid hormone metabolism and activities and affecting
reproduction and development. Echinoderms are prime candidates for this new ecotoxicological approach, since (1) they offer
unique models to study physiological regenerative processes and (2) in echinoderms vertebrate-type steroids can be synthesized
and used as terminal hormones along the neuro-endocrine cascades regulating reproductive, growth and developmental processes.
We are currently exploring the effects on the regenerative potential of echinoderms of different classes of compounds that
are well known to have ED activity. The present paper focuses on the possible effects of well-known compounds with suspected
androgenic activity such as TPT-Cl (Triphenyltin-chloride) and Fenarimol [(±)-2,4-dichloro-α-(pyrimidin-5-yl) benzhydryl alcohol].
The selected test-species is the crinoid Antedon mediterranea, a tractable and sensitive benthic filter-feeding species which represents a valuable experimental model for investigation
on the regenerative process from the macroscopic to the molecular level. The present investigation employs an integrated approach
which combines exposure experiments and biological analysis utilizing microscopy, immunocytochemistry and biochemistry. The
experiments were carried out on experimentally induced arm regenerations in semistatic controlled conditions with exposure
concentrations comparable to those of moderately polluted coastal zones. The bulk of results obtained so far provide indications
of significant sublethal effects from exposure to TPT-Cl and Fenarimol and mechanisms of toxicity related to developmental
physiology, which are associated with variations in steroid levels in the animal tissues. The results indicate that these
two substances (1) affect growth and development by interfering with the same basic cellular mechanisms of regeneration, such
as cell proliferation, migration and differentiation/dedifferentiation, which are possibly controlled by steroid hormones;
and (2) can induce a number of significant modifications in the timing, modalities and pattern of arm regeneration, which
may involve the activation of cell mechanisms related to steroid synthesis/metabolism.
Physical and Chemical Impacts on Marine Organisms, a Bilateral Seminar Italy-Japan held in November 2004 相似文献
9.
Yuxiong Huang Manyu Gao Wenjing Wang Ziyi Liu Wei Qian Ciara Chun Chen Xiaoshan Zhu Zhonghua Cai 《Frontiers of Environmental Science & Engineering》2022,16(9):122
10.
Hydrophobic organic contaminants (HOCs)—pyrene, and natural organic matters (NOM) from different sources were taken as the test compounds to investigate the impact of physicochemical characteristics of NOM on HOCs’ partition to the NOM in this study. The effects of solution property, NOM characteristics, and modification by ozone preoxidation on pyrene partition to NOM were systematically evaluated. According to the fluorescence quenching method, the partition coefficient K oc of pyrene to NOM was calculated, which was found to have a great relationship with the aromatic structures and hydrophobic functional groups of the NOM. The NOM characteristic modification corresponding to solution property could influence the interactions between the NOM and pyrene. Preozonation could destroy the aromatic or hydrophobic structures of the NOM and decrease K oc of pyrene. 相似文献
11.
The stability of H+, NH 4 + , and PO 4 3? ions in rainwater samples was in vestigated under different conditions cf storage and transport. Microbiological and physicochemical processes account for changes. Suppression of microbiological activities in deposition networks using conventional analyses may be achieved by adding AgCl-powder and by cooling to +4 °C. 相似文献
12.
三氯酚暴露致稀有鮈鲫肝脏损伤的比较蛋白质组研究 总被引:1,自引:0,他引:1
为探讨2,4,6-三氯酚(2,4,6-TCP)暴露致鱼类肝脏损伤的毒性效应,以稀有鮈鲫(Gobiocypris rarus)为模式生物,TCP暴露浓度为1、10、100μg·L-1,进行流水暴露实验(28d),利用二维凝胶电泳方法(2-DE),结合质谱分析技术(MALDI-TOF-MS),对TCP致稀有鮈鲫肝脏损伤的蛋白表达谱进行了研究.结果显示,共发现35个差异蛋白点,其中11个蛋白被成功鉴定(C.I.>95%).对鉴定的蛋白根据GOTerms进行功能分类,发现它们主要参与脂类代谢与转运、氧化应激以及蛋白修复和氧化磷酸化等生物学过程。以上结果表明,TCP对稀有鮈鲫具有明显的肝脏毒性效应. 相似文献
13.
Antibiotics are used widely in human and veterinary medicine, and are ubiquitous in environment matrices worldwide. Due to their consumption, excretion, and persistence, antibiotics are disseminated mostly via direct and indirect emissions such as excrements, sewage irrigation, and sludge compost and enter the soil and impact negatively the natural ecosystem of soil. Most antibiotics are amphiphilic or amphoteric and ionize. A non-polar core combined with polar functional moieties makes up numerous antibiotic molecules. Because of various molecule structures, physicochemical properties vary widely among antibiotic compounds. Sorption is an important process for the environment behaviors and fate of antibiotics in soil environment. The adsorption process has decisive role for the environmental behaviors and the ultimate fates of antibiotics in soil. Multiply physicochemical properties of antibiotics induce the large variations of their adsorption behaviors. In addition, factors of soil environment such as the pH, ionic strength, metal ions, and organic matter content also strongly impact the adsorption processes of antibiotics. Review about adsorption of antibiotics on soil can provide a fresh insight into understanding the antibiotic-soil interactions. Therefore, literatures about the adsorption mechanisms of antibiotics in soil environment and the effects of environment factors on adsorption behaviors of antibiotics in soil are reviewed and discussed systematically in this review. 相似文献
14.
不同类型表面活性剂对1,2,4-三氯苯的增溶作用 总被引:6,自引:0,他引:6
研究了阴离子表面活性剂十二烷基硫酸钠、阳离子表面活性剂十六烷基三甲基溴化铵和非离子表面活性剂脂肪醇聚氧乙烯醚LAE对1,2,4-三氯苯(TCB)的增溶作用。讨论了表面活性剂类型对增溶作用的影响。比较发现,非离子型表面活性剂的增溶能力高于离子型表面活性剂。其原因主要是疏水有机物在非离子表面活性剂胶束中的增溶方式不同造成的。3种表面活性剂对TCB的增溶数据还表明,增港作用不仅在临界胶束浓度(MC)以上发生,而且在表面活性剂浓度低于CMC时亦有明显的增溶作用。 相似文献
15.
横向流超滤膜污染动力学模型 总被引:1,自引:0,他引:1
从超滤过程中面滤饼层内对流传输、反向传输和颗粒积累的质量平衡关系出发,建立了描述渗透通量随时间变化关系的横向流超滤膜污染动力学模型,该模型将通常难以确定的滤饼层比阻和反向扩散系数包含在两个经验参数a,b中,通过简单的实验确定参数值后,即可用于横向流超滤过程的数学模拟,模拟计算结果与实验实测数据比较接近,且从理论上说明了横向流超滤从非平衡到最终平衡过渡的原理以及半透膜压,膜面剪切率对渗透通量的影响。 相似文献
16.
Alicia Fernández Cirelli Carlos Ojeda Mariano J. L. Castro Miquel Salgot 《Environmental Chemistry Letters》2008,6(3):135-148
Surfactants are included in different detergent formulations and are one of the most ubiquitous and important families of
organic compounds. Although the generic term applies to a great number of products, 80% of their demand is covered by only
ten types of compounds. The global surfactant market volume size is more than 18 million tons per year. Large quantities of
surfactants are continuously released into the environment, where they can or cannot be degraded depending on their structure.
The alkylbenzenesulphonate (LAS) is the most widely used surfactant. LAS can be degraded under aerobic conditions but is persistent
in the environment under anaerobic conditions. Surfactants may enter the terrestrial environment through several routes, with
the use of sewage sludge as fertiliser on agricultural land being by far the most important. High concentrations of surfactants
and their degradation products may affect the biota. On the other hand, due to their amphiphilic nature, surfactants may interact
both with inorganic as well as organic contaminants affecting their bioavailability. 相似文献
17.
The use of surfactants in a bioremediation process is aimed at increasing the efficiency of the removal of hydrophobic contaminants from the environment. The subjects of the study were three alkyl polyglucosides (APGs) of different alkyl chain length: Glucopon 215 CS UP, Glucopon 600 CS UP, and Glucopon 650 EC. The impact of these surfactants on the surface properties of the test strain Pseudomonas fluorescens ATCC 14700, as well as on the biodegradation of diesel was tested. It was observed, that the length of alkyl chain has an influence on the cell surface properties. The modification of the cell surface hydrophobicity and the electrokinetic potential on the bacteria cells is dependent on the structure of Glucopon molecules. The elongation of alkyl chains in surfactant molecule caused an increase of the hydrophobic properties and a reduction of the electrokinetic potential on the bacteria cells. Moreover, the use of APGs below critical micelle concentration caused an increase of diesel oil biodegradation, especially in the case of Glucopons with longer alkyl chain (Glucopon 600 CS UP and 650 EC). The better diesel oil removal by tested strain after surfactant addition was correlated with the hydrophobic properties of bacteria strain. 相似文献
18.
自然环境中,大多数氯代有机污染物厌氧还原脱氯反应是与土壤环境中一些生源要素的生物化学还原过程相伴生。有机污染物的种类、生物有效性以及毒性能够显著影响这些生源要素的转化,反过来,土壤中活跃的氧化还原反应也可以显著影响有机污染物的动力学转化过程。本文从氧化还原顺序上综述了反硝化过程、铁还原过程、硫酸盐还原过程和产甲烷过程对氯代有机污染物厌氧还原脱氯过程的影响与作用机制,旨在为氯代有机污染物在厌氧环境中还原脱氯的过程与机理的进一步研究、以及还原脱氯与微生物介导的生源要素氧化还原过程的耦合作用机制的揭示提供参考。 相似文献
19.
20.
有机粘土矿物对污染环境修复的研究进展 总被引:132,自引:4,他引:132
本文综述了国外在有机粘土矿物对污染环境修复研究方面的最新进展,具体介绍了利用表面活性剂制备有机粘土矿物的方法,不同类型有机粘土矿物的特征,有机粘土矿物对各种有机污染物的吸附行为及机理,在地下水污染的现场修复,土地填埋防渗添加材料和去除工业废水有机污染物等方面的应用。 相似文献