Screening of Panamanian Plant Extracts for Pesticidal Properties and HPLC-Based Identification of Active Compounds

A library of 600 taxonomically diverse Panamanian plant extracts was screened for fungicidal, insecticidal, and herbicidal activities. A total of 19 active extracts were submitted to HPLC-based activity profiling, and extracts of Bocconia frutescens, Miconia affinis, Myrcia splendens, Combretum aff. laxum, and Erythroxylum macrophyllum were selected for the isolation of compounds. Chelerythrine (2), macarpine (3), dihydrosanguinarine (5), and arjunolic acid (8) showed moderate-to-good fungicidal activity. Myricetin-3-O-(6’’-O-galloyl)-β-galactopyranoside (13) showed moderate insecticidal activity, but no compound with herbicidal activity was identified.     

广东省主要媒介害虫抗药性现状、对策研究及其应用

目的：研究广东省主要媒介害虫的抗药性现状及其防制对策。方法：生物测定法、酯酶滤纸法、ＰＣＲ技术及药激法。结果：经系统监测,广东省各监测点主要媒介对常用杀虫剂大部分都产生抗性,个别品系株已产生高度抗性。采用酯酶滤纸法快速检测家蝇抗药性及应用ＰＣＲ技术监测家蝇抗药性的研究,发现家蝇个体α－Ｎａ酯酶活性频率分布（ＥＦ５０值）与家蝇对ＤＤＶＰ、巴沙的敏感性（ＬＤ５０）呈一定的相关关系。ＤＤＶＰ、巴沙对家蝇     

脑囊尾蚴病患者治疗后脑CT影像学特征变化

目的 探讨脑囊尾蚴病患者抗囊尾蚴治疗期间脑CT影像变化。方法 选择2010年5月至2015年5月在山东省医学科学院第三附属医院就诊的380例脑囊尾蚴病住院患者作为研究对象,临床给予3阶段阿苯达唑、吡喹酮抗囊尾蚴化疗,治疗前后均行头颅CT扫描,其中210例行增强扫描,对治疗不同阶段患者脑CT影像学资料进行分析。结果 脑囊尾蚴病患者治疗前CT影像显示有单个或多个小囊状低密度,囊内可见小结节状高密度头节影,伴周围水肿;治疗后脑CT复查显示81.58% （310/380）的脑囊尾蚴病患者低密度灶完全吸收,16.32% （62/380）病灶大部分吸收,2.11%（8/380）CT影像显示为钙化灶。患者一般于服用抗囊尾蚴药物2～3 d后出现杀虫反应;随着治疗时间的延长,抗囊尾蚴药物反应逐渐减轻,在第3阶段治疗后大多数患者病灶吸收或钙化。结论 CT检查可明确脑囊尾蚴病病变部位、范围,并可对脑囊尾蚴病进行分型,还能根据抗囊尾蚴治疗期间影像学变化评价治疗效果。     

陕西省淡色库蚊抗药性研究

目的了解陕西省不同地区淡色库蚊对常用杀虫剂的抗性水平。方法采用区分剂量法测定淡色库蚊幼虫对4种杀虫剂的24 h死亡率;采用半数致死浓度（LC50）法测定淡色库蚊幼虫对8种杀虫剂的LC50。结果区分剂量法测定结果显示,除榆林市淡色库蚊对氯菊酯属初步抗性群体外,其余均为抗性群体;LC50测定结果显示,5个市的淡色库蚊对高效氯氰菊酯、氯菊酯、溴氰菊酯、氯氰菊酯、DDT、DDVP、双硫磷、残杀威的LC50分别为0.001 82～0.012 24、0.008 16～0.094 19、0.000 58～0.005 59、0.002 76～0.020 17、0.100 96～1.296 86、0.144 11～0.512 40、0.001 47～0.007 06、0.234 60～1.182 37 mg/L。宝鸡市淡色库蚊的抗药性普遍较高,除溴氰菊酯、氯氰菊酯、双硫磷3种药剂外,其余抗性倍数均在全省最高,而榆林市淡色库蚊的抗药性则普遍较低,除双硫磷和残杀威外,其余各药抗性倍数均为全省最低。结论蚊虫抗药性的产生与杀虫剂的使用密切相关,在创建卫生城市、卫生县城工作中要科学合理用药,开展抗药性监测,以减缓蚊虫抗药性的产生。     

德国小蠊谷胱甘肽S-转移酶在不同发育阶段活性变化及其在野外种群中的水平

目的研究谷胱甘肽S-转移酶（GSTs）在德国小蠊不同发育阶段（若虫到成虫）与北京地区不同野外种群中的活性水平。方法分别采用分光光度法与药膜法测定德国小蠊GSTs活性与其抗性水平。结果德国小蠊GSTs比活力在若虫期随龄期增加而逐渐升高,在4周龄达到最高;随后逐渐降低,在羽化时酶活力降至最低,在成虫期略有升高。德国小蠊敏感品系成虫GSTs比活力为2.70 nmol（/min.mg）,Km值与Vmax分别为2.26 mmol/L和0.33 nmol（/min.mg）;9个区（县）野外种群GSTs比活力为2.76～8.69 nmol（/min.mg）,Km值和Vmax分别为0.65～2.37 mmol/L和0.33～0.54 nmol（/min.mg）。与敏感品系比较,野外种群成虫GSTs比活力和Vmax均较高,Km值较低,且对2种常用杀虫剂表现出不同程度的抗性（对高效氯氰菊酯为1.50～8.37倍;对残杀威为1.04～3.34倍）。结论 GSTs活性随德国小蠊发育阶段不同（若虫到成虫）而变化,并可能参与德国小蠊野外种群的抗性形成。     

植物源杀虫剂和驱避剂在蚊虫防制中的研究进展

随着人们环保意识的提高,使用化学杀虫剂面临的压力越来越大,开发高效、低毒或无毒、不易产生抗性的植物源杀虫剂和驱避剂已成为蚊虫化学防制的热点.该文综述了近5年植物源杀虫剂和驱避剂在蚊虫防制中的研究进展.     

蚊虫杀虫药剂的抗性及防治策略

蚊虫在长期的化学杀虫剂选择压力下,已从多个生理途径进化出抵抗这种选择压的能力,给我们有效控制一些蚊媒传播的疾病带来困难。该文对蚊虫抗药性的主要分子机制和抗性基因的适合度代价进行剖析,并评述目前国内外防治蚊虫传播疾病的各种策略,以期为我国媒介蚊虫的防治工作提供借鉴。     

江苏省部分地区淡色库蚊幼虫对7种杀虫剂的抗药性研究

目的了解江苏省部分地区淡色库蚊幼虫对常用杀虫剂的抗性状况,指导对蚊幼虫防治药物的合理使用。方法选择7种常用化学杀虫剂,采用幼虫浸渍法对江苏省南京、南通、淮安地区的淡色库蚊幼虫进行抗药性测定。结果与实验室敏感品系比较,南京、南通、淮安地区的淡色库蚊幼虫对敌敌畏抗药性均为最高,南通和淮安种群对氯菊酯的抗药性最低,南京种群对生物丙烯菊酯抗药性最低,对氯菊酯的抗药性与对生物丙烯菊酯的接近。结论在对蚊幼虫防治时,杀虫剂的选择应考虑当地抗药性情况,并合理控制使用,减少使用抗性较高的敌敌畏、残杀威和双硫磷,选用抗药性较低的拟除虫菊酯类杀虫剂。     

浙江省不同地区淡色库蚊杀虫剂抗药性监测

目的对浙江省不同地区淡色库蚊抗药性水平进行调查,了解淡色库蚊的抗性表型与有关基因特征及其相关性,为浙江省蚊虫控制提供科学依据。方法淡色库蚊抗药性表型采用幼虫浸渍法;对浙江省4个区域的淡色库蚊进行抗药性测定,基因型研究采用PCR扩增后测序确定。结果不同地区淡色库蚊抗药性表型差异较大,对高效氯氰菊酯、溴氰菊酯、丙烯菊酯、敌敌畏、三氯杀虫酯、残杀威的半数致死浓度（LC50）分别在同类药物抗性差异变化范围为2．1～42．8倍,其中以高效氯氰菊酯抗性差异最高。舟山种群拟除虫菊酯类药物抗性水平明显高于其他地区,其拟除虫菊酯抗性相关基因YSSC基因具有较高多态性,部分样本V3$C基因内含子区域出现3个紧邻的大小分别为20、53和40bp的片段缺失。结论浙江省不同地区淡色库蚊抗性表型差异较大,抗性基因监测发现舟山种群kdr基因存在较复杂的多态性,是否为导致其抗性表型变化的直接原因还有待进一步研究证实。     

Fifteen Years of Experience in Cholinesterase Monitoring of Insecticide Applicators

Abstract

Introduction: Measuring cholinesterase (ChE) enzyme levels in red blood cells (RBC) and plasma has become a useful tool in the early detection of organophosphate and carbamate poisoning in insecticide handlers. Since 1974 the State of California has required testing of pesticide applicators to prevent disease. This study is a review of the testing experience of two physicians and using one laboratory so that a comparison can be made to previous studies by the author and others.

Methods: The files of 366 workers who were referred by their employers for ChE activity monitoring were abstracted for patient data, employer identification, and testing data. Results were entered into the EPIINFO program for analysis.

Results: A total of 366 workers from 45 companies were tested over a 15-year period between 1989 and 2004. Most were applicators. There were 690 attempts to establish baselines, of which 545 (79%) were successful. There were 519 monitoring tests on 228 workers, resulting in the removal from exposure of 18 employees, most in 1996. Self-reported exposure history and symptoms resulted in only 3 responses (.6%). The costs were significant ($47,160 total and $36 per test), especially when considering the failure of 145 (21%) employees to establish baselines. There was monthly and yearly variation in plasma and RBC baselines, monthly variance in plasma monitoring tests, and no monthly variance in RBC monitoring. The use of a third baseline test when the first two varied by 15% avoided two false positives. The mean time for recovery from ChE depression was 5.38 weeks.

Discussion: The California ChE monitoring program remains a valuable tool. There was significant monthly and yearly variation in values for both baseline and monitoring plasma and RBC values, with the exception of RBC monthly variance. Self-reported symptoms were not found to be a valuable tool in measuring exposure. Rates of recovery from ChE depression were highly variable. The warning feature of the program was very effective. The costs of monitoring were substantial, but possibly not as great as a single workers' compensation case.

Conclusions: The California ChE monitoring program serves as a useful and cost-effective means of preventing organophosphate and carbamate overexposure. Elimination of the third baseline test requirement should be considered.