土壤中氟喹诺酮类药物残留的生态效应及归宿

氟喹诺酮类药物是人工合成的高效广谱抗菌药,对细菌的DNA螺旋酶具有选择性抑制作用,因其具有良好的药物动力学特性及治疗效果,临床应用非常广泛,但同时也引起环境污染.本文综述了氟喹诺酮类药物的理化特性及其对环境的影响,土壤中残留氟喹诺酮类药物的检测以及氟喹诺酮类药物污染土壤的生物修复.     

氟喹诺酮类抗生素在土壤中的归趋及其生态毒性研究进展

氟喹诺酮类抗生素是治疗人和动物细菌性感染的高效广谱抗菌药,因其具有良好的药物动力学特性及治疗效果,临床应用非常广泛.其残留物进入土壤后,会发生吸附、降解、植物吸收等一系列转化过程.本文对土壤中氟喹诺酮类抗生素的主要污染源及其在土壤中的吸附、降解、植物吸收与富集等一系列转化过程进行了分析,并探讨了土壤中氟喹诺酮类抗生素残留所引起的生态效应,旨在为土壤污染防治和修复提供依据.     

氟喹诺酮类抗生素心脏毒性机制的研究进展

氟喹诺酮类抗生素的心脏不良反应较为罕见,但产生的后果严重,所以倍受关注。本文从离子通道角度、动作电位水平和心电图表现等方面对氟喹诺酮类药物心脏毒性电生理机制的研究进展进行综述。     

结核分枝杆菌耐氟喹诺酮类药物的分子机制研究进展

结核病是由结核分枝杆菌(Mycobacterium tuberculosis)通过空气传播引起人类感染的慢性传染病,耐药结核分枝杆菌的流行是目前结核病防治的世界难题。氟喹诺酮类药物是人工合成药物,应用于耐药结核的临床治疗中,在治疗中起着核心的作用。但近年来,氟喹诺酮类药物的抗性菌株不断出现,愈发增加了结核病治疗的困难与治疗失败风险。在临床中氟喹诺酮药物的靶点比较清楚,是结核分枝杆菌的DNA旋转酶。目前发现结核分枝杆菌耐氟喹诺酮类药物的机制主要包括药物靶点DNA旋转酶的关键氨基酸改变、药物外排泵系统、细菌细胞壁厚度的增加以及喹诺酮抗性蛋白MfpA介导的DNA旋转酶活性调控。其中在氟喹诺酮靶标DNA旋转酶功能活性改变的耐药机制方面,编码DNA旋转酶基因突变一直是研究的热点,但近年来发现DNA旋转酶的调控蛋白MfpA以及DNA旋转酶的修饰在细菌耐药性中起着重要的作用,相关机制还亟待发现。本文综述了当前结核分枝杆菌耐氟喹诺酮类药物的作用机制,旨在为研发精准诊断技术和药物发掘提供科学理论基础和参考。     

肺炎克雷伯杆菌对氟喹诺酮耐药的机制研究

目的研究肺炎克雷伯杆菌对氟喹诺酮类药物（FQNs）的耐药机制。方法筛选临床分离的对环丙沙星耐药的肺炎克雷伯杆菌共10株,采用微量肉汤稀释法检测菌株对5种氟喹诺酮类药物的MIC值;采用PCR方法检测菌株染色体和质粒携带的喹诺酮耐药基因（gyrA基因、parC基因和qnr基因）并测序;质粒接合试验验证qnr基因的转移性。结果 10株肺炎克雷伯杆菌对5种氟喹诺酮类药物均产生耐药性。扩增产物经测序发现10株肺炎克雷伯杆菌染色体的gyrA基因和parC基因均有突变;有2株菌株（K79和K107）携带qnrA基因,这2株菌的接合菌对喹诺酮抗菌药的MIC值上升了5～30倍;未检测到qnrB阳性的菌株。结论 gyrA和parC基因突变是肺炎克雷菌对氟喹诺酮类产生耐药机制的主要原因,质粒上qnrA基因的存在,也是产生喹诺酮耐药的一个重要因素。     

氧氟沙星在鲤体内的药物动力学和残留研究

氧氟沙星(Ofloxacin)是氟喹诺酮类药物之一, 由日本第一制药株式会社于1982 年开发的, 由于分子的基本结构中引入了疏水性的氟原子及亲水性的哌嗪环, 其抗菌活性得到了增强、细菌耐药性大大降低。       

氟喹诺酮类抗生素及耐药基因污染控制的研究进展北大核心CSCD

氟喹诺酮类抗生素属于喹诺酮类抗生素,是一类人畜通用的抗生素。近年来,被广泛应用于人类和畜牧、水产等养殖业领域,然而其大量使用,造成在环境中的不断残留和累积,给自然环境和人类健康造成了较大威胁。现有研究表明,微生物降解是有效去除氟喹诺酮类抗生素残留污染的有效方法之一。本文总结和介绍了近年来氟喹诺酮类抗生素微生物降解单株菌和混合菌群、微生物降解酶、降解途径以及微生物降解氟喹诺酮类抗生素的实际应用,并对目前氟喹诺酮类抗生素微生物降解研究中存在的问题进行了分析,以及对未来氟喹诺酮类抗生素微生物降解研究的重点进行了探讨,以期为后续的研究提供参考。     

氟喹诺酮类药物的光化学性质及其光敏毒性机理

氟喹诺酮类药物(fluoroquinolones,FQs)是目前得到广泛应用的广谱、高效的合成抗菌素。本文通过对FQs光化学研究进展的介绍,详述了具有代表性的FQs的光物理、光化学性质及光化学反应途径,以及其对生物分子的光敏损伤机理等。FQs具有较高的三重激发态产额,其激发态能够发生多种光化学反应,此类反应极易受到溶剂性质和某些盐类的影响,其光敏毒性与其分子结构有着密切的联系,尤其受8位取代基的影响非常大。对该类药物光化学性质和光敏毒性机理的研究,将会对此类药物的合理使用和新一代药物的研发提供很好的理论依据。     

肠沙门菌副伤寒甲血清型的萘啶酸抗性和克隆扩散

目的了解玉溪市1999年至2008年甲型副伤寒患者肠沙门菌甲型副伤寒血清型(SPA)分离株的萘啶酸抗性和克隆扩散。方法采用有对照的K-B纸片扩散技术对4060株SPA进行抗微生物药物敏感性试验;对随机选择的166个萘啶酸抗性(NAR)株和20个萘啶酸敏感(NAS)株进行SpeI消化染色体DNA脉冲场凝胶电泳(PFGE)分型、聚类分析以及氟喹诺酮最小抑菌浓度(MIC)测定。结果分离株的NAR率由1999年的12.5%、2000年82.2%、2001年93%上升到2008年的100%;NAS株在1999年占优势,但在2000年以后被NAR株替代;166个NAR株都降低了对氟喹诺酮类药物的敏感性,其MIC值比20个NAS株的高得多。186个菌株SpeI消化产物得出以SpeI01、SpeI02型占优势的9种PFGE型。结论萘啶酸筛检实验可用于检测SPA降低氟喹诺酮敏感性,SpeI01和SpeI02是玉溪流行的主要克隆,建议制定并实施氟喹诺酮药物抗性株引起爆发流行的处理方案。     

铜绿假单胞菌parC基因突变与耐氟喹诺酮的关系

研究了成都地区临床分离的铜绿假单胞菌拓扑异构酶ⅣparC基因突变与耐氟喹诺酮类药物的关系。测定临床分离的55株铜绿假单胞菌的MIC值,从中筛选出1株敏感菌和8株耐药菌,以标准敏感菌株ATCC27853作为质控菌株。用PCR反应扩增parC基因的喹诺酮耐药决定区(QRDR),扩增产物片段长度为396bp,同时对上述10株菌的PCR产物进行测序分析。临床分离敏感菌和标准菌株ATCC27853的parC基因序列与国外报道的序列相同,而R25,R42,R43,R44等4株耐药菌株在87位(TCGCG→TTG)均有突变,该单位点突变引起氨基酸由Ser→Leu的改变,此外,新发现在所有耐药菌株115位有一静止突变(GCT→GCG),该突变未引起氨基酸的改变。拓扑异构酶ⅣparC基因突变是铜绿假单胞菌对氟喹诺酮类药物产生耐药性的机制之一,以87位的突变最为常见。     

Impact of Firm-Based Environmental Standards on Subsidiaries and Their Suppliers: Evidence from Motorola-Penang

How successful are multinational corporations in extending their firm-based environmental standards to their subsidiaries and those subsidiaries' local suppliers in their global production networks in developing countries? We address this question through an in-depth case study of how Motorola, a prominent multinational electronics firm with an extensive global production network, is using a set of firm-based standards to meet several new stringent European Union environmental directives. The case study demonstrates that these firm-based standards appear to be enabling a major subsidiary and its suppliers in one developing economy to reduce the environmental intensities of their production activities. This finding suggests that the firm-based environmental standards of multinationals with extensive global production networks might contribute to a leveling up of environmental standards in subsidiaries and their local suppliers, rather than a "race to the bottom", thus reinforcing the technique or intensity effects associated with open trade, investment, and technology policies.     

Corporate environmental performance,environmental information disclosure,and financial performance: Evidence from China

As pollution emitters and energy users, firms are important causes of environmental problems, making it increasingly vital for them to strengthen their environmental management and information disclosure policies. However, firms doubt whether it pays to be green and whether it is worthwhile to disclose their environmental information, and there are hot debates on these questions in the literature. This paper analyzes the relationships among corporate environmental performance, environmental information disclosure, and financial performance in China, which witnessed rapid growth at the price of environmental degradation. With 950 observations from 475 Chinese listed companies between 2013 and 2014, we find a U-shaped nonlinear relationship between corporate environmental performance and environmental disclosure, an insignificant relationship between environmental performance and financial performance, and a negative relationship between environmental disclosure and financial performance, which is different from most findings in developed countries. The aforementioned results imply that Chinese firms have few motivations to disclose environmental information or improve environmental performance; therefore, mandatory disclosure of environmental information is necessary, and proper environmental policy should be made to punish environmental violations and encourage better environmental performance.     

Visibility of the impact of environmental noise: a response to Kaitala and Ranta

Based on simulation modelling, Kaitala and Ranta (2001 Proc. R. Soc. Lond. B 268, 1769-1774) have argued that detecting the statistical relationships between environmental variability and population fluctuations will be difficult. However, their study was limited in that only one pattern of density dependence and one detection method were used. Here, we show that their conclusion is in part a consequence of their choice of population model and in part a consequence of using relatively weak or inappropriate statistical methods. Other patterns of density dependence respond differently to environmental fluctuations, and the impact of the disturbance on these is clearly visible using their methods. For some patterns of population dynamics, environmental impacts are more readily detectable by correlating running-average environmental conditions with the population time-series or by correlating the first differences of the population time-series with environmental noise. When more appropriate statistical methods are used, environmental forcing is detectable in the majority of cases used by Kaitala and Ranta. The interplay between environmental stochasticity and density-dependent population growth means that there is no single best method to detect the influence of environmental forcing, even when population dynamics are approximately linear. But environmental forcing will often be detectable, contrary to Kaitala and Ranta's assertions.     

生物标志物（Biomarkers）在海洋环境监测中的研究与进展

污染物的存在给海洋环境和生态健康带来了巨大的压力,如何监测这些污染物并对其毒性进行科学的评价,成为当今环境科学关心的热点问题。生物标志物（Biomarkers）是毒理学研究的重要工具,它能对污染事件进行早期预警,并能在一定程度上评估生态风险。对近十多年来生物标志物的研究与应用进行了回顾,总结了不同水平（分子、细胞、个体、系统）生物标志物的种类、特征、检测方法和应用特点,并对现存挑战和未来发展趋向进行了展望,旨在系统的认识生物标志物,并为其在海洋环境监测中的合理应用提供理论借鉴。     

MicroRNA在环境毒理学中的研究进展

MicroRNA（miRNA）是一类长为20～24nt的非编码单链小分子RNA,主要存在于真核生物中,具有组织特异性、无开放阅读框等特点,在转录或翻译水平调控基因表达,参与细胞增殖、分化、凋亡,并与炎症、肿瘤等疾病发生、发展密切相关。环境毒理学研究表明,当生物暴露于环境化学物质时,会引起相关miRNA表达发生变化,进而导致其靶基因表达发生改变。因此,有必要明确环境化学物质、miRNA和相关靶基因三者问的作用关系。在环境毒理学研究和环境监测中,miRNA可作为识别环境中化学物质基因毒性和致癌性的生物标记物,并可用于预测环境化学物质对生物体的毒性。     

A Framework for Information Systems in Life-Cycle-Oriented Environmental Management

Although business firms have improved their environmental performance, a variety of forces are pushing businesses toward adopting environmental management throughout the entire life cycle of their products and processes. In this article we discuss the information systems elements of an environmental management approach we call "life-cycle-oriented environmental management" (LCOEM).This approach requires the firm to manage the effects of its processes from the creation of inputs to the final disposal of outputs, that is, from cradle to grave. We present a framework of the classes of information systems needed, describe their use in an LCOEM setting and define their inter relationships. We conclude with a discussion of the implications of LCOEM information systems.     

Residents’ concerns about lake uses and environments: a comparative study of Lakes Kasumigaura,Suwa, and Biwa in Japan

Lakes are a common water resource. This study analyzed residents’ concerns regarding their lake environments to help solve lake environmental problems. The study area comprised three lakes in Japan—Kasumigaura, Suwa, and Biwa—which have different tendencies to change in water quality. A sample of 1200 respondents was evenly distributed among the three lake regions. A questionnaire survey asked about respondents’ proximity to the lake, their concerns about the lakes’ uses and environments, their evaluations of the lakes, and their opinions regarding environmental improvements. The number of options chosen in response to the multiple-answer questions was used to measure the extent of concern. The results found that knowledge of the water environment, general environmental concerns, the amount of travel time to the lake, and the visiting interval were significantly related to concerns about the lake environment. The results of logistic regression analysis found that high environmental concerns positively influenced attitudes toward lake use. Ways to increase concerns for lake environmental problems and the relationship between concerns and attitudes toward solving lake environmental problems are discussed.     

Longitudinal Analysis of the Eco‐Design Management Standardization Process in Furniture Companies

This article discusses how eco‐design management standards have been adopted and the environmental and economic results that have been obtained by the Spanish furniture manufacturers. This is precisely the industry sector in Spain where the dissemination of eco‐design standards has been most important. Using multiple case‐study methodology, the research has shown that, in three companies, more than 90% of the environmental impact of the companies’ products occurs within the manufacturing phase. Companies have implemented tools for life cycle assessment with eco‐indicators values that allow them to assess complex products and evaluate their significant environmental impacts at each stage. The environmental strategies of these companies are based on the continuous improvement of the internal processes and the review and monitoring of their activities. In this approach, the proper choice of materials and the environmental management of the supply chain are the main problems for companies. The outcomes achieved by the companies included some improvements, such as a greater control of product management and a reduction in operating costs, that have allowed them to obtain competitive advantages. Moreover, the adoption of standard management has enabled the companies to drive innovation of products, improve the image of companies and their products, significantly reduce the environmental impact of their products, and adapt to new, more demanding environmental laws and regulations.     

美国、加拿大环境和健康风险管理方法

对目前美国和加拿大多个部门使用的风险评价与风险管理方法进行了全面回顾和综合分析,论述各种不同方法的特征,深入探讨各种管理方法的基础、利弊、使用经验,辨识环境、人类健康和职业健康风险综合方法中应该包含的要素,阐述风险管理目标的确定方法,以期为中国的环境风险管理提供经验。