Evaluation of metaflumizone granular fly bait for management of houseflies

The housefly, Musca domestica L. (Diptera: Muscidae), is a pest of great veterinary and public health importance. In this study, the efficacy of metaflumizone granular fly bait was assessed on first generation (F1) housefly adults raised from flies collected at a cattle feedlot in Kansas. All bioassays were conducted as choice tests, with flies having ad libitum access to water, granular sugar and bait. A commercial methomyl-based bait (Golden Malrin^TM) was used as positive control; no bait (water and granular sugar only) was used as negative control. Fly mortality was recorded on days 2, 7 and 14. The metaflumizone bait was significantly more slow-acting than the methomyl bait (mortality rates after 2 days of exposure were 49.9% and 57.9%, respectively). However, there were no significant differences in cumulative mortality later in the bioassays. Cumulative mortality rates on days 7 and 14 were 96.1% (metaflumizone), 91.4% (methomyl) and 99.0% (metaflumizone), 97.6% (methomyl), respectively. Our results demonstrate that the metaflumizone granular fly bait may be an effective modality for incorporation into management programmes for houseflies in and around livestock production facilities as well as in residential settings.     

Maize <Emphasis Type="Italic">Lc</Emphasis> transcription factor enhances biosynthesis of anthocyanins,distinct proanthocyanidins and phenylpropanoids in apple (<Emphasis Type="Italic">Malus domestica</Emphasis> Borkh.)

Flavonoids are a large family of polyphenolic compounds with manifold functions in plants. Present in a wide range of vegetables and fruits, flavonoids form an integral part of the human diet and confer multiple health benefits. Here, we report on metabolic engineering of the flavonoid biosynthetic pathways in apple (Malus domestica Borkh.) by overexpression of the maize (Zea mays L.) leaf colour (Lc) regulatory gene. The Lc gene was transferred into the M. domestica cultivar Holsteiner Cox via Agrobacterium tumefaciens-mediated transformation which resulted in enhanced anthocyanin accumulation in regenerated shoots. Five independent Lc lines were investigated for integration of Lc into the plant genome by Southern blot and PCR analyses. The Lc-transgenic lines contained one or two Lc gene copies and showed increased mRNA levels for phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), flavanone 3 beta-hydroxylase (FHT), dihydroflavonol 4-reductase (DFR), leucoanthocyanidin reductases (LAR), anthocyanidin synthase (ANS) and anthocyanidin reductase (ANR). HPLC-DAD and LC-MS analyses revealed higher levels of the anthocyanin idaein (12-fold), the flavan 3-ol epicatechin (14-fold), and especially the isomeric catechin (41-fold), and some distinct dimeric proanthocyanidins (7 to 134-fold) in leaf tissues of Lc-transgenic lines. The levels of phenylpropanoids and their derivatives were only slightly increased. Thus, Lc overexpression in Malus domestica resulted in enhanced biosynthesis of specific flavonoid classes, which play important roles in both phytopathology and human health.     

Health departments in the U.S. 1920-1988: statements of mission with special reference to the role of C.-E.A. Winslow.

The mission of local health departments in the U.S. is traced from the 1920s to the present through examination of official promulgations of the American Public Health Association and other organizations. As the communicable diseases came under general control, this mission was conceived more broadly. Nevertheless, in effect their public health role was diminished due to the rapid ascendancy of private and not-for-profit medical care, which consistently sought to keep public health out of potential areas of competition. Thinking both within the public health field (as represented by C.-E.A. Winslow) and outside the public health field (as represented by the American Medical Association), had created boundaries limiting public health's role to preventive medical services. This restriction, in turn, largely excluded the public health field from participation in the tremendous expansion of medical care since World War II. The public health role was further limited in 1970 by the removal of much of environmental pollution from its purview. The sum of these and other forces has left the public health field weakened and in considerable confusion about its role at a time when the resurgence of infectious disease (e.g., AIDS and Lyme disease), environmental hazards, and medical care institutions requires a strong public health presence.     

Determination of malathion and diazinon resistance by sequencing the Md alpha E7 gene from Guatemala, Colombia, Manhattan, and Thailand housefly (Musca domestica L.) strains

Organophosphate (OP) insecticides (parathion/diazinon) resistance in housefly (Musca domestica L.) is associated with the change in carboxylesterase activity. The product of alpha E7 gene, which is a member of alpha-esterase gene cluster, is probably playing a role in detoxification of the xenobiotic esters. In parathion/diazinon resistant M. domestica species Gly137 to Asp substitution was found in the active center of the product of alpha E7 gene. In malathion (an OP) resistant M. domestica strains Trp251 to Ser substitution was identified in the active center of the Md alpha E7. In our research, to understand the allelic diversity of the Md alpha E7, the gene was partially sequenced from four different housefly strains from different localities (Guatemala, Manhattan (USA), Colombia (USA) and Thailand). It was found out that; in Thailand strain one allele has Cys residue at the position of 251, the other allele contains a Trp for the same site. In Colombia strain, one allele has Asp137, the other allele contains a Gly residue at this point. The Manhattan and Guatemala strains have Asp137 and Trp251 residues on their both alleles at these two different positions.     

抗溴氰菊酯家蝇在不同用药方式下的敏感性变化及其机制

以具有极高抗水平的抗溴氰菊酯家蝇Musca domestica vicina Macquart DR0品系为试虫,模拟田间几种常见的用药方式(混用、轮用、使用增效剂),在室内进行平行汰选,并以不用药和继续用原药汰选的为比较,研究试虫在这几种用药方式下的敏感性变化及其变化机制。抗性家蝇用辛溴混剂、辛硫磷以及溴氰菊酯＋SV₁汰选后,在F₁₆(F₁₇)代以前,对溴氰菊酯及汰选药剂的抗性发展相对都比较缓慢;F₁₆(F₁₇)代以后,用溴氰菊酯＋SV₁汰选的家蝇对溴氰菊酯的敏感性迅速下降,抗性发展很快。家蝇对溴氰菊酯的敏感性变化与药剂中溴氰菊酯的选择压有关。生化分析结果表明,在不同用药方式汰选下,家蝇体内酯酶、多功能氧化酶、谷胱甘肽-S-转移酶、乙酰胆碱酯酶的酶活或特性发生了不同的变化。     

DIFFERENCES IN SUSCEPTIBILITY TO INSECTICIDES BETWEEN ADULTS AND LARVAE OF HOUSEFLY, MUSCA DOMESTICA (L.)

Abstract  In this paper, we reported the differences in susceptibility to insecticides between adults and larvae of housefly, Musca domestica (L.), and the mechanisms for the differences. The larvae of housefly were much more tolerant to insecticides than the adults, and the tolerance ratio to cyhalothrin was as high as 205.5 for susceptible strain. Mechanism studies showed that higher GST activity was associated with higher insecticide tolerance in the larvae. The co-toxicity coefficient of the mixture of cyhalothrin and methylene dithiocyanate(4:1) on pyrehid-resistant houseflies was 188.     

EFFECTS OF CADMIUM ON HOUSEFLY: INFLUENCE ON GROWTH AND DEVELOPMENT AND METABOLISM DURING METAMORPHOSIS OF HOUSEFLY

Abstract The objective of this study was to elucidate the effects of cadmium on housefly, Musca domestica. It is suggested that of cadmium in low concentrations of had little influence on growth and development of housefly. Cadmium was mainly distributed in the digestive tracts of housefly larvae, where the cadmium content was higher than that of other parts. During the metamorphosis of housefly the change trend of the cadmium content was very apparent. The cadmium content increased gradually in larval period, whereas it decreased significantly after polarization. Until the sixth day after emergence, only negligible cadmium was left in adult housefly. All these results demonstrated that the response of housefly to cadmium is an evolution adaptation in natural selection.     

STUDIES ON A CADMIUM-INDUCED METALLOTHIONEIN IN HOUSEFLY LARVAE, MUSCA DOMESTICA

Abstract  The induction of metallothionein (MT) was studied in the housefly larvae ( Musca domestica ). Upon dietary exposure to Cd, two Cd-binding proteins were isolated from the whole body homogenates, using gel filtration and ion exchange chromatography. Mass spectrometric measurement revealed that they have high purity and the molecular weight are 9045.9Da and 11560.2Da, respectively. Amino acid analysis showed that the content of cysteine is the highest, attaining to 18.2%. However, aromatic amino acid residues such as tyrosine (2.5%) and phenylalanine (3.1%) were also detected. In addition, MT from housefly larvae has strong heat stability. All these results suggest that the properties of MT isolated from housefly are very similar to that of mammalian MT, but some differences still exist.     

Cd^2＋对家蝇生长发育的影响以及在家蝇变态过程中的代谢研究

研究重金属镉对家蝇生长发育的影响,以及镉在家蝇变态过程中的代谢。结果表明：低浓度的Cd^2 对家蝇的生长分育几乎没有什么影响,而高浓度的Cd^2 则影响家蝇卵孵化率,幼虫相对存活率,化蛹率,羽化率,百头幼虫理和百头蛹重。进入家蝇幼虫体内的Cd^2 主要分布在消化道,其次是体壁,脂肪体和血淋巴中含量很少。在家蝇变态过程中,Cd^2 的含量变化趋势十分明显：幼虫期Cd^2 逐渐累积,化蛹后Cd^2 含量大幅度下降,羽化后的第6天,成虫体内只剩下极微量的Cd^2 。这些结果表明家蝇对环境中重金属镉的反应是一种在自然选择过程中形成的高度的进化适应。     

拟除虫菊酯抗性家蝇的交互抗药性研究

拟除虫菊酯的广泛使用使家蝇普遍产生了抗药性,为有效的控制家蝇的危害,需要了解家蝇对轮换或新杀虫剂的交互抗性状况。作者用点滴法测定了两个实验室汰选的拟除虫菊酯抗性家蝇品系对几种杀虫剂的交互抗性,结果表明:二氯苯醚菊酯和溴氰菊酯之间存在较高程度的交互抗药性;拟除虫菊酯抗性较高的家蝇对作用机制不同的新农药(多杀菌素、氟虫腈)表现较低程度的交互抗性。     

家蝇幼虫组织匀浆液的抗病毒活性

以家蝇Musca domesticaL.幼虫为材料,研究了蝇蛆组织匀浆液的抗病毒活性。用鸡胚培养检测了其抗流感病毒的活性,乙型肝炎病毒表面抗原诊断试剂盒检测了其对乙型肝炎病毒表面抗原的破坏作用。结果表明:15μL的家蝇幼虫组织匀浆液对流感病毒的抑制率为72.41%,而30,50和80μL剂量组对病毒的杀灭率都达到80%以上;蝇蛆组织匀浆液对乙型肝炎病毒表面抗原的破坏率可达到87.5%。说明家蝇幼虫体内存在着抗病毒活性物质。这为开发天然的抗病毒药物提供了新的途径。     

DIPTEREX RESISTANCE IN THE HOUSEFLY AND THE SYNERGIC MECHANISM OF SV1 IN RELATION TO PENETRATION THROUGH CUTICLE

Abstract  SV₁ was observed to have obvious synergism and could delay housefly ( Musca domestica vicina ) resistance development to Dipterex. The penetration rates of Dipterex through housefly cuticle were determined in a susceptible and two resistant strains. The results indicated that the penetration in the resistant housefly strains was obviously slower than in the susceptible one. The penetrating rate of SV₁+ Dipterex (in mixture) was higher than that of Dipterex. The penetration reduction in resistant houseflies may be an important factor in bringing forth resistance. The increase of the penetrating rate of Dipterex and the decrease of its metabolic rate are regarded as the important mechanisms of SV₁ synergism to Dipterex.     

Influence of Frequently Used Chemical Insecticides on Mycoflora Carried by Common Housefly, <Emphasis Type="Italic">Musca domestica</Emphasis> L.

The housefly, Musca domestica L. (Diptera: Muscidae), is a major medical and veterinary insect pest. It serves as a vector of many pathogenic microorganisms causing spoilage of food and diseases in human and animals. Use of chemical insecticides is adapted as a principal tool to manage housefly. Insecticides have many unforeseen ecological consequences including effects on non-target organisms. In the present study, we have assessed the effects of 10 different synthetic insecticides on the growth of mycoflora associated with the external body of the housefly by using poison food technique. Our results reveled that all synthetic insecticides enhanced the growth. Surprisingly, in most of the cases, mycelial growth of fungi was significantly increased at high concentration as compared with lower concentration. This study provides useful information about the dangerous effects of synthetic insecticides on environment by increasing the spread of various non-target pathogenic, mycotoxigenic, and food spoiling fungi, carried by houseflies.     

金黄角头小蜂及寄主新纪录(膜翅目:小蜂科)

金黄角头小蜂Dirhinus auratus Ashmead(小蜂科:角头小蜂亚科)在中国大陆首次纪录,研究标本均由家蝇蛹放于室外诱集后饲养获得;家蝇蛹为金黄角头小蜂的寄主新记录.本文提供了金黄角头金小蜂形态描述、分布及形态特征图.研究标本保存在中国科学院动物研究所动物标本馆及安徽师范大学标本馆.     

石蒜总生物碱对家蝇的生物活性

在室内测定了石蒜总生物碱对家蝇的生物活性,表明石蒜总生物碱对家蝇具有一定的触杀作用和生长发育抑制作用.石蒜总生物碱不同浓度(15、12、9、6、3 mg/mL)、不同作用时间(24 h、36 h、48 h、60 h、72 h)以及它们的交互作用分别对家蝇幼虫和成虫的触杀作用有显著影响.当石蒜总生物碱的浓度为15 mg/mL时,家蝇幼虫(3龄早期)和成虫(羽化3d)平均校正死亡率最高,分别为40.96％和38.25％,随着浓度的降低,触杀作用逐渐降低,随着作用时间的延长,触杀作用逐渐增强,72 h的平均校正死亡率分别达39.35％和37.55％,但总生物碱对家蝇幼虫和成虫的触杀作用间无显著差异.处理24、36、48、60、72 h后,石蒜总生物碱对家蝇幼虫的LC50值分别为57.42、36.48、21.92、13.13和10.95 mg/mL,对成虫的LC50值分别为86.66、37.86、23.91、14.15和11.51 mg/mL.老熟幼虫的平均重量除了在3 mg/mL时与对照差异不显著,其他各浓度下都显著低于对照,而在各浓度下的化蛹率、蛹的平均重量和羽化率均显著低于对照.     

The function and structural influence of selective relaxed constraint at functional intracellular loop3 of 5-HT(1A) serotonin-1 receptor family

Superoxide dismutases (SODs) are metalloenzymes that represent one important line of defense against reactive oxygen species (ROS). In this paper, two novel SOD genes, MdSOD1 and MdSOD2, which putatively encode 261 and 214 amino acid residues respectively were identified and characterized from the housefly Musca domestica. The high similarity of MdSOD1 and MdSOD2 with SODs from other organisms indicated that they should be two new members of the SOD family. qPCR exhibited a universal expression of MdSOD1 and MdSOD2 detected in various tissues of housefly larva, including the fat body, gut, hemocyte and epidermis. Expression profiling reveals that MdSOD1 and MdSOD2 can be induced significantly via not only heat shock and cadmium (Cd) stress but also Escherichia coli and Staphylococcus aureus challenge. The two genes were cloned into the prokaryotic expression vector pET-28a to obtain the fusion proteins rMdSOD1 and rMdSOD2. Between them, the activity of rMdSOD2 was found by visual assay methods. ESI-LC-MS/MS analysis showed that three peptide fragments of the protein rMdSOD2 were identical to the corresponding sequence of M. domestica MdSOD2. MdSOD1 and MdSOD2 in housefly larvae were abrogated by feeding bacteria expressing dsRNA. High mortalities were observed in the larvae treated with dsRNA of SODs at heat shock, Cd stress and bacterial invasion. This phenomenon indicated that MdSOD1 and MdSOD2 are related to the survival of M. domestica under stress. This may provide new insights into the role of the two SOD genes in protecting M. domestica against both stress and bacterial invasion.     

Fenitroxon insensitive acetylcholinesterases of the housefly, Musca domestica associated with point mutations

The cDNA of AChE in the housefly, Musca domestica, was sequenced and individual flies were genotyped by this gene in an inhibition assay of AChE activity with an organophaspate, fenitroxon. Mutations at Gly(342) and Tyr(407), which are reportedly conserved in resistant strains of Drosophila, were associated with the insensitivity to fenitroxon. Two other mutations, Ile(162) and Val(260), did not have an apparent effect on insensitivity. However, the four mutations are located in the active site of the enzyme, and therefore the non-neutral mutations in this gene are considered to cause the insensitivity of AChE in the development of insecticide resistance of the housefly.     

显微注射法制备转基因家蝇技术的建立

旨在利用显微注射法对早期家蝇(Musca domestica L.)卵注射含有增强型绿色荧光蛋白(Enhanced green fluorescent protein,EGFP)基因的转座子载体,实现活体基因稳定表达并对其进行验证,为开展家蝇基因功能的研究奠定基础。文中自制适用于显微注射家蝇卵的硼硅酸盐玻璃微量注射针,摸索出家蝇卵壳的软化处理条件,以NanojectⅢ高精度微量注射器为主体构建适用于家蝇的显微注射技术平台;将含有眼部特异表达的3×P3启动子、EGFP的重组质粒PiggyBac-[3×P3]-EGFP与稳定遗传表达辅助质粒pHA3pig helper显微注射到处理过的家蝇卵中,待羽化观察眼部发光情况,检测EGFP的表达及转录水平。结果表明,将家蝇卵在漂白水中漂洗35 s时卵的正常孵化率为55%,处理35 s的卵壳其硬度适宜注射且注射针头不易破碎;羽化后的家蝇眼部带有绿色荧光的占比约为3%,通过分子检测,家蝇的DNA和RNA中均扩增出EGFP特异片段,大小为750 bp。通过该技术平台,能够便捷、有效地实现报告基因在家蝇中的稳定表达,建立以家蝇为主体的生物反应器,为后续家蝇基因功能的研究提供一定参考价值。     

土荆芥生物总碱对家蝇的毒杀作用及药剂敏感性的影响

通过室内毒力测定和生化分析方法,测定了土荆芥生物总碱对敌百虫抗性种群,溴氰菊酯抗性种群,敏感种群等3个家蝇(Musca domestica)种群成虫的毒杀效果,土荆芥生物总碱处理前后家蝇种群成虫对溴氰菊酯和敌百虫的药剂敏感性变化,以及对家蝇成虫羧酸酯酶和谷胱甘肽-S-转移酶的活力的影响。结果表明,土荆芥生物总碱不仅对家蝇有毒杀效果,处理后能提高家蝇对杀虫剂的敏感性,而且能抑制家蝇体内解毒酶系活性。土荆芥生物总碱对不同种群家蝇成虫的LD_(50)没有显著差异;土荆芥生物总碱处理前后,敌百虫对抗性种群和敏感种群的LD_(50)比值分别为1.6277和1.2914,溴氰菊酯对抗性种群和敏感种群的LD_(50)比值分别为2.0768和1.3871;土荆芥生物总碱处理前后,家蝇敌百虫抗性种群、溴氰菊酯抗性种群和敏感种群成虫的羧酸酯酶活性比值分别为1.1692、1.2947和1.2259,谷胱甘肽-S-转移酶活性比值分别为1.2476、1.6519和1.0570。     

戊型肝炎病毒研究新进展

戊型肝炎病毒(hepatitis E virus,HEV)是引起全球多地区大规模流行和散发病例的急性病毒性肝炎的病原体,发展中国家尤为突出;我国是戊型肝炎(hepatitis E,HE)流行的高发区.HE是一种人畜共患病,猪是人HEV病毒的主要储库,因而HE已成为一个全球性的的公共卫生问题.对HEV的病毒学和基因组特征、临床表征、流行病学、主要抗原表位以及HEV诊断试剂和疫苗研制的进展进行了综述.