912 resultados para FLIES DIPTERA TEPHRITIDAE


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Horseflies are economically important blood-feeding arthropods and also a nuisance for humans, and vectors for filariasis. They rely heavily on the pharmacological propriety of their saliva to get blood meat and suppress immune reactions of hosts. Little information is available on horsefly immune suppressants. By high-performance liquid chromatography (HPLC) purification coupling with pharmacological testing, an immunoregulatory peptide named immunoregulin HA has been identified and characterized from salivary glands of the horsefly of Hybomitra atriperoides (Diptera, Tabanidae). Immunoregulin HA could inhibit the secretion of interferon-gamma (IFN-gamma) and monocyte chemoattractant protein (MCP-1) and increase the secretion of interteukin-10 (IL-10) induced by lipopolysaccharide (LIPS) in rat splenocytes. IL-10 is a suppressor cytokine of T-cell proliferative and cytokine responses. IL-10 can inhibit the elaboration of pro-inflammatory cytokines. Immunoregulin HA possibly unregulated the IL-10 production to inhibit IFN-gamma and MCP-1 secretion in the current experiments. This immunosuppression may facilitate the blood feeding of this horsefly. The current works will facilitate to understand the molecular mechanisms of the ectoparasite-host relationship. 2008 Elsevier Ltd. All rights reserved.

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Horseflies are economically important blood-feeding arthropods and also a nuisance for humans and vectors for filariasis. They rely heavily on the pharmacological properties of their saliva to get a blood meal and suppress immune reactions of hosts. Little information is available on antihemostatic substances in horsefly salivary glands; especially no horsefly immune suppressants have been reported. By proteomics or peptidomics and coupling transcriptome analysis with pharmacological testing, several families of proteins or peptides, which act mainly on the hemostatic system or immune system of the host, were identified and characterized from 30,000 pairs salivary glands of the horsefly Tabanus yao (Diptera, Tabanidae). They are: (i) a novel family of inhibitors of platelet aggregation including two members, which possibly inhibit platelet aggregation by a novel mechanism and act on platelet membrane, (ii) a novel family of immunosuppressant peptides including 12 members, which can inhibit interferon-gamma production and increase interleukin-10 secretion, (iii) a serine protease inhibitor with 56 amino acid residues containing anticoagulant activity, (iv) a serine protease with anticoagulant activity, (v) a protease with fibrinogenolytic activity, (vi) three families of antimicrobial peptides including six members, (vii) a hyaluronidase, (viii) a vasodilator peptide, which is an isoform of vasotab identified from Hybomitra bimaculata, and interestingly (ix) two metallothioneins, which are the first metallothioneins reported from invertebrate salivary glands. The current work will facilitate the understanding of the molecular mechanisms of the ectoparasite-host relationship and help in identifying novel vaccine targets and novel leading pharmacological compounds.

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The Ag5 proteins are the most abundant and immunogenic proteins in the venom secretory ducts of stinging insects. An antigen 5-like protein (named tabRTS) composed of 221 amino acid residues was purified and characterized from the salivary glands of the horsefly, Tabanus yao (Diptera, Tabanidae). Its cDNA was cloned from the cDNA library of the horsefly's salivary gland. TabRTS containing the SCP domain (Sc7 family of extracellular protein domain) was found in insect antigen 5 proteins. More interestingly, there is an Arg-Thr-Ser (RTS) disintegrin motif at the C-terminus of tabRTS. The RTS motif is positioned in a loop bracketed by cysteine residues as those found in RTS-disintegrins of Crotalidae and Viperidae snake venoms, which act as angiogenesis inhibitors. Endothelial Cell Tube formation assay in vitro and chicken chorioallantoic membrane (CAM) angiogenesis assay in vivo were performed as to investigate the effect of tabRTS on angiogenesis. It was found that tabRTS could significantly inhibit angiogenesis in vitro and in vivo. Anti-alpha(1)beta(1) monoclonal antibody could dose-dependently inhibit the anti-angiogenic activity of tabRTS. This result indicated that tabRTS possibly targets the alpha(1)beta(1) integrin to exert the anti-angiogenic activity as snake venom RTS-/KTS-disintegrins do. The current work revealed the first angiogenesis inhibitor protein containing RTS motif from invertebrates, a possible novel type of RTS-disintegrin. (C) 2009 Elsevier Ltd. All rights reserved.

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Liriomyza huidobrensis Blanchard (Diptera: Agromyzidae) is a very serious and economically important pest around the world. Liriomyza huidobrensis in China was first reported from Kunming of Yunnan province in 1993. We report here that this pest has recen

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Lar lake, with the international UTM specification of 39S 579680 3976567 & 39S 589930 3976184 is Situated in Lar national Park with an aerial distance of 55 Km of Tehran along Haraz road. The present research is carried out as part of a comprehensives Plan for assessment of bioresearches of Lar lake & the rivers flowing into it. This research includes examination of there benthic Samplings performed in Lar lake and each of the related rivers including Delichaee, Ab-e-sefid , Alarm & Lar (Kamardasht).Tubifex and Chironomus genus were found to have the highest frequencies of occurrence in the lake with %77.117 & %21.823 respectively followed by Chironomidae and Simulidae from the Diptera order which accounted for %72.328 and %13.812 occurrences in four rivers examined in the Study. The benthic biomass at various examined Sites and the average wet weight of the benthic biomass in station No one in the lake Was 17.397g and the figure for the examined site in Alarm was 20.242 g which were the highest level among Other examination stations the index for the abundance of species in Alarm river was greater than the rest of the examined rivers with 12.57. A sum of 354 Pieces of brown trouts was caught in the course of sampling which were closely investigated in terms of their digestive tract Content. It was identified that Daphniidae and Chironomus constituted the bulk of eaten items from the lake with %17.985 and %63.973 respectively. Meanwhile, Chironomidae and Simuladae were the most frequently eanten benthos by the fish with %81.47 and %7.93 respectively.The index for the relative length of gut was recorded at 0.49± 0.08 which is well indicative of the carnivorous diet of the fish.The index for the feeding intensity amounted to 138  83 showing that the one year old fish were of more feeding intensity.The coefficient of condition (K) was estimated at 1.02  0.142 for all the caught fish. The average wet weight of the benthos was 10.348 g per square meter which if extended to 700ha surface area of the lake, the total macrobenthic production in the lake would amount to 72730Kg of wet weight or 6510 Kg of dry weight. Since the Secondary Production of macrobenthos have always been double that of their biomass, it is reasonable to assume that the Secondary Production of macrobenthos amount to 145640 Kg by their wet weight and Since the energy transfer in the food chain of the lake from benthos to fish is 10 percent, the fish production Capacity Coming from benthic resources of the lake (Lar) would be 14.5 MT, half of which (7000-8000MT) could annually be harvested. Further more, the actual fish Production Capacity might exceed the projected level Since Daphnia, Rotifers and Ostracoda which belong to Zooplanktons, play a part in the natural diet of trout. Meanwhile, rivers Play a major role in fish nutrition and the annual fish production in Delichaee river is about 4481.8Kg while the figures for Ab-e-sefid, Alerm and Lar rivers are 2370.7 4848.7 and 2586.2 Kg respectively, that further increase fish Production in the area and every year half of these resources can be exploitable from the river & the lake.Nevertheless, due to ecological & biological importance of rivers and the probability of environmental Pollution, devastation of natural fish habitats & their nursery grounds, Sport fishing is not recommended at all.

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Acoustic communication in drosophilid flies is based on the production and perception of courtship songs, which facilitate mating. Despite decades of research on courtship songs and behavior in Drosophila, central auditory responses have remained uncharacterized. In this study, we report on intracellular recordings from central neurons that innervate the Drosophila antennal mechanosensory and motor center (AMMC), the first relay for auditory information in the fly brain. These neurons produce graded-potential (nonspiking) responses to sound; we compare recordings from AMMC neurons to extracellular recordings of the receptor neuron population [Johnston's organ neurons (JONs)]. We discover that, while steady-state response profiles for tonal and broadband stimuli are significantly transformed between the JON population in the antenna and AMMC neurons in the brain, transient responses to pulses present in natural stimuli (courtship song) are not. For pulse stimuli in particular, AMMC neurons simply low-pass filter the receptor population response, thus preserving low-frequency temporal features (such as the spacing of song pulses) for analysis by postsynaptic neurons. We also compare responses in two closely related Drosophila species, Drosophila melanogaster and Drosophila simulans, and find that pulse song responses are largely similar, despite differences in the spectral content of their songs. Our recordings inform how downstream circuits may read out behaviorally relevant information from central neurons in the AMMC.

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In most parts of China, mosquitoes have been subjected to organophosphate (OP) insecticide treatments since the mid-1960s, and resistance gene monitoring in the Culex pipiens complex (Diptera: Culicidae) started in only a few locations from the end of the 1980s. Many resistant alleles at the Ester locus have been found in field populations, including those commonly found around the world (Ester(B1) and Ester(2)), and those endemic to China (Ester(B6), Ester(B7), Ester(8), and Ester(9)). This situation is atypical, and may represent a complex situation for the evolution of insecticide resistance genes in China. To increase our understanding of the Chinese situation and our ability to manage resistance in the C. pipiens complex, a large study was performed. Twenty field populations were sampled from Beijing to Guangzhou. Bioassays with five insecticides (dichlorvos, parathion, chlorpyrifos, 2-sec-butylphenyl methyl carbamate, and propoxur) disclosed resistance levels variable according to the geographic origin, and up to 85-fold for dichlorvos. Six overproduced esterases were identified, including two that have not been previously described. Most of them were found in all samples, although at variable frequencies, suggesting variable selection or a transient situation, e.g., each one was recently restricted to a particular geographic area. The results are discussed in the context of recent alterations to insecticide campaigns, and of the evolution of resistance genes in Chinese C. pipiens populations.

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Surveys of macroinvertebrates were carried out in the Xiangxi River system during July of 2001. Among the 121 taxa collected, Ephemeroptera, Trichoptera, and Diptera dominated (41.7, 26.0, and 24.5% of the total relative abundance, respectively). Two-way indictor species analysis and detrended correspondence analysis divided the 49 sites into four groups based on species composition and relative abundance. Canonical correspondence analysis indicated that elevation, SiO2, pH, conductivity, hardness, and NO2-N were significant environmental factors affecting the distribution of macroinvertebrates.

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果蝇 virilis section(Hsu 1949)自建立以来其合理性在果蝇系统发育中还没有得到 检验。本文以线粒体烟酰胺腺嘌呤二核苷酸脱氢酶第二亚单位基因(ND2)全序列和细 胞色素氧化酶I 基因(COI)部分片段以及核中乙醇脱氢酶基因Adh 的编码区为遗传标 记,对virilis section 内61 个物种(13 个未发表新种),共计117 个个体进行了序列测 定。通过对单个基因和合并数据集进行简约分析,以及对合并数据集进行邻接法分析 和贝叶斯分析,本研究试图对以下问题进行探讨:(1)果蝇virilis section 的合理性。 (2)各种组间的系统关系。(3)种组内部各物种间的系统关系。(4)果蝇virilis section 的进化历史。现将主要结果总结如下: 1)分子系统学研究显示果蝇virilis section 为一个紧密相关的进化簇,为果蝇virilis section 的合理性从分子遗传学的角度提供了证据。 2)系统发育分析支持果蝇polychaeta 种组为单系群,该种组与未归类物种D. fluvialis 具有较近的亲缘关系。它们形成virilis section 中早期分化出的谱系。robusta 种组、melanica 种组、quadrisetata 种组以及新种组间关系较近。其中,robusta 种亚 组和melanica 种组关系较近;quadrisetata 种组和新种组形成姐妹群,它们形成的谱 系与robusta 种组内的okadai 种亚组关系紧密。 3) polychaeta 种组内部分为两枝,姐妹种D. polychaeta 和D. asper 组成其中一枝, 杂交实验显示它们具有非对称的交配前生殖隔离。另一枝中D. latifshahi 和D. daruma 显示了较近的亲缘关系。非洲物种D. hirtipes 与采自西双版纳的D. polychaeta X 关系 较近,提示它们可能有共同的起源。 4)合并数据集支持D. angor 种组为单系群,其中D. angor A 和D. velox 的姐妹种 关系得到较高的支持。但是该种组内部的其它物种间关系还需要进一步研究。 5) 分子系统发育分析结果清楚地表明robusta 种组属于多系发生。该种组被分为 三个种亚组:okadai 种亚组,robusta 种亚组和lacertosa 种亚组。在lacertosa 种亚组 内,D. bai 与其它成员相对远缘。okadai 种亚组的物种由于具有2n = 12 条染色体,且X 染色体为棒状,因而被认为是robusta 种组中较早分化出来的类群。但是我们的 分子数据并不支持这种观点。D. moriwakii 最初被描述为robusta 种组物种,后被订正 至melanica 种组。我们的系统发育分析显示该种与robusta 种亚组具有较近的关系, 而与melanica 种组物种的关系相对较远。除D. moriwakii 外,melanica 种组新旧大陆 物种各自形成单系。在系统树上,中国品系D. tsigana 与D. longiserrata 关系较近, 而与日本品系D. tsigana 的关系较远。杂交实验结果显示D. tsigana 中国品系和日本 品系间存在不对称的交配倾向,表明该种不同的地理群体间可能正处于分化阶段,而 中国品系则有可能已经演化为不同的物种。 6)果蝇quadrisetata 种组为单系发生,其内部分为两个明显的亚世系。第一个亚 世系包括D. sp T,D. barutani,D. potamophila 和D. spIZU;另一个亚世系包括D. beppui,D. karakasa,D. quadrisetata,D. multidentata,D. perlucida 和D. pilosa,其 中D. beppui 为该谱系中最早分化出的物种。 通过估计谱系间的分歧时间,本文推测果蝇virilis section 的祖先大约于中新世早 期起源于热带地区,virilis section 内许多物种可能栖息在旧大陆的低纬度地区,然后 通过适应性辐射扩散到各地。几乎所有的新大陆virilis section 物种是旧大陆物种通过 白令陆桥迁移到新大陆而演化形成的。

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20 0 0年 10月~ 2 0 0 1年 10月对下辽河平原地区撂荒、林地、旱田、水田 4种不同土地利用方式的土壤微节肢动物进行了调查 .应用个体数密度、类群丰富度、多样性指数和均匀度 4个群落参数 ,研究了土壤微节肢动物的群落结构和季节变化 .结果表明 ,撂荒中土壤微节肢动物的 4个群落参数均为最高 ,旱田均为最低 ,季节变化影响土壤微节肢动物的群落结构 ,但土地利用方式不影响群落结构的季节变化型 .下辽河平原地区不同土地利用方式共鉴定出土壤微节肢动物 12个类群 ,撂荒、林地、旱田中弹尾目 (Collem bola)和蜱螨目 (Acarina)为优势类群 ,双翅目 (Diptera)、鞘翅目 (Coleoptera)和膜翅目 (Hymenoptera)为常见类群 ,水田中弹尾目、蜱螨目和双翅目为优势类群 ,鞘翅目为常见类群 .各土地利用方式、各季节均在表层土壤出现的类群最多、密度最高 ,中层次之 ,底层最少