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Sample records for biostable insect kinin

  1. Antifeedant activity and high mortality in the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae) induced by biostable insect kinin analogs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The insect kinins are multifunctional neuropeptides found in a variety of arthropod species, including the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae). A series of biostable insect kinin analogs based on the shared C-terminal pentapeptide core region were fed in solutions of artificial diet t...

  2. Biostable agonists that match or exceed activity of native insect kinins on recombinant arthropod GPCRs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The multifunctional arthropod insect kinins share the evolutionarily conserved C-terminal pentapeptide motif Phe-X1-X2-Trp-Gly-NH2, where X1 = His, Asn, Ser, or Tyr and X2 = Ser, Pro, or Ala. Insect kinins regulate diuresis in many species of insects. Compounds with similar biological activity cou...

  3. Biostable insect kinin analogs reduce blood meal and disrupt ecdysis in the blood-gorging Chagas' disease vector, Rhodnius prolixus.

    PubMed

    Lange, Angela B; Nachman, Ronald J; Kaczmarek, Krzysztof; Zabrocki, Janusz

    2016-06-01

    Rhodnius prolixus is a blood-gorging hemipteran that takes blood meals that are approximately 10 times its body weight. This blood meal is crucial for growth and development and is needed to ensure a successful molt into the next instar. Kinins are a multifunctional family of neuropeptides which have been shown to play a role in the control of feeding in a variety of insects. In this study, two biostable Aib-containing kinin analogs were tested to see if they interfere with blood-feeding and subsequent development into the next instar. One of the analogs, 1729 (Ac-R[Aib]FF[Aib]WGa), had no effect on the size of the blood meal or on the subsequent molting of the insect into the next instar. This analog also did not interfere with either short-term or long-term diuresis. The second analog, 1728 ([Aib]FF[Aib]WGa), appeared to be an antifeedant. Insects feeding on blood containing this analog (15μM) only consumed 60% of the blood meal taken by insects fed on blood without analog. Insects feeding on blood containing 1728 had a slower rate of rapid diuresis (diuresis in the first 3-5h after feeding) leading to less urine being excreted by 5days post feeding. The consequence of these effects was that insects fed on 1728 did not molt. This data indicates that the biostable Aib-containing analog 1728 disrupts normal growth and development in the blood-feeding insect, R. prolixus. PMID:26807486

  4. Biostable analogs of insect kinin and insectatachykinin neuropeptides: Novel antifeedants and aphicides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Neuropeptides are potent regulators of critical life processes in insects, but are subject to rapid degradation by peptidases in the hemolymph (blood), tissues and gut. This limitation can be overcome via replacement of peptidase susceptible portions of the insect neuropeptides with non-natural resi...

  5. Biostable insect kinin analogs reduce blood meal and disrupt ecdysis in the blood-gorging Chagas’ disease vector, Rhodnius prolixus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rhodnius prolixus is a blood-gorging hemipteran that takes blood meals that are approximately 10 times its body weight. This blood meal is crucial for growth and development and is needed to ensure a successful molt into the next instar. Kinins are a multifunctional family of neuropeptides which hav...

  6. Identifications of selective and non-selective, biostable beta-amino acid agonists of recombinant insect kinin receptors from the Southern cattle tick, Boophilus microplus, and mosquito, Aedes aegypti

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The multifunctional arthropod ‘insect kinins’ share the evolutionarily conserved C-terminal pentapeptide motif Phe-X1-X2-Trp-Gly-NH2, where X1 = His, Asn, Ser, or Tyr and X2 = Ser, Pro, or Ala. Eight different analogs of the insect kinin C-terminal pentapeptide active core in which the critical res...

  7. Coordination ability of insect kinin analogs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spectroscopic data, including electronic absorption, CD and EPR results, as well as theoretical calculations have shown that the insertion of 4-aminopyroglutamate, a novel cis-ppetide bond mimic, in the insect kinin peptide leads to an effective ligand towards Cu(II) ions at basic pH ranges. The 4-a...

  8. Design, synthesis and aphicidal activity of N-terminal modified insect kinin analogs.

    PubMed

    Zhang, Chuanliang; Qu, Yanyan; Wu, Xiaoqing; Song, Dunlun; Ling, Yun; Yang, Xinling

    2015-06-01

    The insect kinins are a class of multifunctional insect neuropeptides present in a diverse variety of insects. Insect kinin analogs showed multiple bioactivities, especially, the aphicidal activity. To find a biostable and bioactive insecticide candidate with simplified structure, a series of N-terminal modified insect kinin analogs was designed and synthesized based on the lead compound [Aib]-Phe-Phe-[Aib]-Trp-Gly-NH2. Their aphicidal activity against the soybean aphid Aphis glycines was evaluated. The results showed that all the analogs maintained the aphicidal activity. In particular, the aphicidal activity of the pentapeptide analog X Phe-Phe-[Aib]-Trp-Gly-NH2 (LC50=0.045mmol/L) was similar to the lead compound (LC50=0.048mmol/L). This indicated that the N-terminal protective group may not play an important role in the activity and the analogs structure could be simplified to pentapeptide analogs while retaining good aphicidal activity. The core pentapeptide analog X can be used as the lead compound for further chemical modifications to discover potential insecticides. PMID:25116632

  9. Potential metal atom binding sites in insect kinin analogs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potentiometric and spectroscopic data, including CD and EPR results, as well as theoretical calculations have shown that the insertion of (2R,4R)-4-aminopyroglutamate (apy), a novel cis-peptide bond mimic, in the insect kinin peptide, Ac-Arg-Phe-apy-Trp-Gly-NH2 leads to a very effective chelating ag...

  10. A C-terminal aldehyde analog of the insect kinins inhibits diuresis in the housefly

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The insect kinins are present in a wide variety of insects and function as potent diuretic peptides in flies. A C-terminal aldehyde insect kinin analog, Fmoc-RFFPWG-H (R-LK-CHO), demonstrates stimulation of Malpighian tubule fluid secretion in crickets, but shows inhibition of both in vitro and in v...

  11. Active diuretic peptidomimetic insect kinin analogs that contain Beta-turn mimetic motif 4-aminopyroglutamate and lack native peptide bonds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The multifunctional arthropod 'insect kinins' share the evolutionarily conserved C-terminal pentapeptide core sequence Phe-X1-X2-Trp-Gly-NH2, where X1 = His, Asn, Ser, or Tyr and X2 = Ser, Pro, or Ala. Insect kinins regulate diuresis in many species of insects, including the cricket. Insect kinins...

  12. Comparison of insect kinin analogs with cis-peptide bond motif 4-aminopyroglutamate identifies optimal stereochemistry for diuretic activity.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The insect kinins are present in a wide variety of insects and function as potent diuretic peptides, though they are subject to rapid degradation by internal peptidases. Insect kinin analogs incorporating stereochemical variants of (2S,4S)-4-aminopyroglutamate (APy), a cis-peptide bond motif, demon...

  13. Towards the development of novel pest management agents based upon insect kinin neuropeptide analogs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect kinin neuropeptides share a common C-terminal pentapeptide sequence Phe1-Xaa123-Xaa23-Trp4-Gly5-NH2 (Xaa12=His, Asn, Phe, Ser or Try; Xaa23=Pro, Ser, or Ala) and have been isolated from a number of insects. They have been associated with the regulation of such diverse processes as hindgut co...

  14. The Molecular Characterization of the Kinin Transcript and the Physiological Effects of Kinins in the Blood-Gorging Insect Rhodnius prolixus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The dramatic feeding-related activities of the Chagas' disease vector, Rhodnius prolixus are under neurohormonal regulation of serotonin and various neuropeptides. One such family of neuropeptides, the insect kinins, possess diuretic, digestive and myotropic activities in many insects. In this study...

  15. Active peptidomimetic insect kinin analogs with type VI turn motif 4-aminopyroglutamate lack native peptide bonds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two stereochemical variant insect kinin mimetic analogs 1796 and 1797 containing (2S,4S)-APy (APy) and (2R,4S)-APy (Apy), respectively, were synthesized and evaluated on isolated Malpighian tubules of the house cricket Acheta domesticus to determine if they could retain the fluid secretion stimulat...

  16. Interaction of mimetic analogs of insect kinin neuropeptides with arthropod receptors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect kinin neuropeptides share a common C-terminal pentapeptide sequence Phe1-Xaa1-2-Xaa2-3-Trp4-Gly5-NH2 (Xaa1-2 = His, Asn, Phe, Ser or Tyr; Xaa2-3 = Pro, Ser or Ala) and have been isolated from a number of insects, including species of Dictyoptera, Lepidoptera, and Orthoptera. They have been a...

  17. A C-TERMINAL INSECT KININ ANALOG ENHANCES INHIBITION OF WEIGHT GAIN AND INDUCES SIGNIFICANT MORTALITY IN HELICOVERPA ZEA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The first reported examples of C-terminal aldehyde analogs of an insect neuropeptide are described. They are hexapeptide insect kinin analogs Boc-VFFPWG-H and Fmoc-RFFPWG-H. Activity observed for these modified analogs in an in vitro insect diuretic assay confirms that the C-terminal aldehyde group...

  18. Eco-Friendly Insecticide Discovery via Peptidomimetics: Design, Synthesis, and Aphicidal Activity of Novel Insect Kinin Analogues.

    PubMed

    Zhang, Chuanliang; Qu, Yanyan; Wu, Xiaoqing; Song, Dunlun; Ling, Yun; Yang, Xinling

    2015-05-13

    Insect kinin neuropeptides are pleiotropic peptides that are involved in the regulation of hindgut contraction, diuresis, and digestive enzyme release. They share a common C-terminal pentapeptide sequence of Phe(1)-Xaa(2)-Yaa(3)-Trp(4)-Gly(5)-NH2 (where Xaa(2) = His, Asn, Phe, Ser, or Tyr; Yaa(3) = Pro, Ser, or Ala). Recently, the aphicidal activity of insect kinin analogues has attracted the attention of researchers. Our previous work demonstrated that the sequence-simplified insect kinin pentapeptide analogue Phe-Phe-[Aib]-Trp-Gly-NH2 could retain good aphicidal activity and be the lead compound for the further discovery of eco-friendly insecticides which encompassed a broad array of biochemicals derived from micro-organisms and other natural sources. Using the peptidomimetics strategy, we chose Phe-Phe-[Aib]-Trp-Gly-NH2 as the lead compound, and we designed and synthesized three series, including 31 novel insect kinin analogues. The aphicidal activity of the new analogues against soybean aphid was determined. The results showed that all of the analogues exhibited aphicidal activity. Of particular interest was the analogue II-1, which exhibited improved aphicidal activity with an LC50 of 0.019 mmol/L compared with the lead compound (LC50 = 0.045 mmol/L) or the commercial insecticide pymetrozine (LC50 = 0.034 mmol/L). This suggests that the analogue II-1 could be used as a new lead for the discovery of potential eco-friendly insecticides. PMID:25912216

  19. Aib-containing analogues of the insect kinin neuropeptide family demonstrate resistance to an insect angiotensin-converting enzyme and potent diuretic activity.

    PubMed

    Nachman, R J; Isaac, R E; Coast, G M; Holman, G M

    1997-01-01

    Analogues of the insect kinin family in which the Xaa2 residue of the C-terminal pentapeptide core sequence Phe-Xaa1-Xaa2-Trp-Gly-NH2 (Xaa1 = Asn, His, Phe, Ser, or Tyr; Xaa2 = Ala, Ser, or Pro) is replaced with sterically hindered aminoisobutyric acid (Aib) prove to be resistant to hydrolysis by housefly (Musca domestica) angiotensin-converting enzyme (ACE), an endopeptidase capable of hydrolysis and inactivation of the naturally occurring insect kinin peptides. The Aib residue is compatible with formation of turn in the active core region that is important for the biological activity of the insect kinins. One of the Aib-containing analogues, pGlu-Lys-Phe-Phe-Aib-Trp-Gly-NH2, is five- and eightfold more active than the most active endogenous insect kinins in cockroach (Leucophaea maderae) hindgut myotropic and cricket (Acheta domesticus) Malpighian tubule fluid secretion assays, respectively. As the analogue is blocked at both the amino- and the carboxyl-terminus and resistant to an endopeptidase present in insects, it is better adapted than the endogenous peptides to survive for long periods in the hemolymph. Enzyme-resistant insect kinin analogues can provide useful tools to insect researchers studying the neuroendocrine control of water and ion balance and the physiological consequences of challenging insect with diuretic factors that demonstrate enhanced resistance to peptidase attack. If these analogues, whether in isolation or in combination with other factors, can disrupt the water and/or ion balance they hold potential utility for the control of pest insect populations in the future. PMID:9114452

  20. Induction of Selective Blood-Tumor Barrier Permeability and Macromolecular Transport by a Biostable Kinin B1 Receptor Agonist in a Glioma Rat Model

    PubMed Central

    Côté, Jérôme; Bovenzi, Veronica; Savard, Martin; Dubuc, Céléna; Fortier, Audrey; Neugebauer, Witold; Tremblay, Luc; Müller-Esterl, Werner; Tsanaclis, Ana-Maria; Lepage, Martin; Fortin, David; Gobeil, Fernand

    2012-01-01

    Treatment of malignant glioma with chemotherapy is limited mostly because of delivery impediment related to the blood-brain tumor barrier (BTB). B1 receptors (B1R), inducible prototypical G-protein coupled receptors (GPCR) can regulate permeability of vessels including possibly that of brain tumors. Here, we determine the extent of BTB permeability induced by the natural and synthetic peptide B1R agonists, LysdesArg9BK (LDBK) and SarLys[dPhe8]desArg9BK (NG29), in syngeneic F98 glioma-implanted Fischer rats. Ten days after tumor inoculation, we detected the presence of B1R on tumor cells and associated vasculature. NG29 infusion increased brain distribution volume and uptake profiles of paramagnetic probes (Magnevist and Gadomer) at tumoral sites (T1-weighted imaging). These effects were blocked by B1R antagonist and non-selective cyclooxygenase inhibitors, but not by B2R antagonist and non-selective nitric oxide synthase inhibitors. Consistent with MRI data, systemic co-administration of NG29 improved brain tumor delivery of Carboplatin chemotherapy (ICP-Mass spectrometry). We also detected elevated B1R expression in clinical samples of high-grade glioma. Our results documented a novel GPCR-signaling mechanism for promoting transient BTB disruption, involving activation of B1R and ensuing production of COX metabolites. They also underlined the potential value of synthetic biostable B1R agonists as selective BTB modulators for local delivery of different sized-therapeutics at (peri)tumoral sites. PMID:22629405

  1. Biostable and PEG polymer-conjugated insect pyrokinin analogs demonstrate antifeedant activity and induce high mortality in the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pyrokinins are multifunctional neuropeptides found in a variety of arthropod species, including the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae). A series of biostable pyrokinin analogs based on the shared C-terminal pentapeptide core region were fed in solutions of artificial diet to the ...

  2. Agonists/Antagonists of the insect kinin and pyrokinin/PBAN neuropeptide classes as tools for rational pest control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The IK and PK/PBAN insect neuropeptide classes regulate critical aspects of water balance, digestion, reproduction, defense and development in insects. These neuropeptides are nonetheless subject to degradation by peptidases in the hemolymph and gut of insects and, for the most part, lack efficient ...

  3. Comparison of insect kinin analogs with cis-peptide bond, type VI-turn motifs identifies optimal stereochemistry for interaction with a recombinant arthropod kinin receptor from the Southern cattle tick, Boophilus microplus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The multifunctional ‘insect kinins’ share the evolutionarily conserved C-terminal pentapeptide motif Phe-X1-X2-Trp-Gly-NH2, where X1 = His, Asn, Ser, or Tyr and X2 = Ser, Pro, or Ala; and are associated with the regulation of diuresis in a variety of species of insects. We previously reported the f...

  4. Identification of kinin-related peptides in the disease vector, Rhodnius prolixus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have used an in silico approach to identify a gene from the blood-gorging vector, Rhodnius prolixus, that is predicted to produce an insect kinin prepropeptide. The prepropeptide is 398 amino acids in length and can potentially produce a large number of kinin-related peptides following post-tran...

  5. Kinins and peptide receptors.

    PubMed

    Regoli, Domenico; Gobeil, Fernand

    2016-04-01

    This paper is divided into two sections: the first contains the essential elements of the opening lecture presented by Pr. Regoli to the 2015 International Kinin Symposium in S. Paulo, Brazil on June 28th and the second is the celebration of Dr. Regoli's 60 years of research on vasoactive peptides. The cardiovascular homeostasis derives from a balance of two systems, the renin-angiotensin system (RAS) and the kallikrein-kinin system (KKS). The biologically active effector entity of RAS is angiotensin receptor-1 (AT-1R), and that of KKS is bradykinin B2 receptor (B2R). The first mediates vasoconstriction, the second is the most potent and efficient vasodilator. Thanks to its complex and multi-functional mechanism of action, involving nitric oxide (NO), prostacyclin and endothelial hyperpolarizing factor (EDHF). B2R is instrumental for the supply of blood, oxygen and nutrition to tissues. KKS is present on the vascular endothelium and functions as an autacoid playing major roles in cardiovascular diseases (CVDs) and diabetes. KKS exerts a paramount role in the prevention of thrombosis and atherosclerosis. Such knowledge emphasizes the already prominent value of the ACE-inhibitors (ACEIs) for the treatment of CVDs and diabetes. Indeed, the ACEIs, thanks to their double action (block of the RAS and potentiation of the KKS) are the ideal agents for a rational treatment of these diseases. PMID:26408609

  6. Increased kinin levels and decreased responsiveness to kinins during aging.

    PubMed

    Pérez, Viviana; Velarde, Victoria; Acuña-Castillo, Claudio; Gómez, Christian; Nishimura, Sumiyo; Sabaj, Valeria; Walter, Robin; Sierra, Felipe

    2005-08-01

    Kinins are vasoactive peptides released from precursors called kininogens, and serum levels of both T- and K-kininogens increase dramatically as rats age. Kinin release is tightly regulated, and here we show that serum kinin levels also increase with age, from 63 +/- 16 nmol/L in young Fisher 344 rats to 398 +/- 102 nmol/L in old animals. Both K- and T-kininogens contribute sequentially to this increase, with the increase in middle-aged animals being driven primarily by K-kininogen, whereas the further augmentation in older rats occurs by increasing T-kininogen. By measuring ERK activation, we show that aorta endothelial cells from old animals are hyporesponsive to exogenous bradykinin. However, if serum kinin levels are experimentally decreased by lipopolysaccharide treatment, then the endothelial response to bradykinin is re-established. These results indicate that serum levels of kinins increase with age, whereas the responsiveness of target cells to kinins is reduced in these same animals. PMID:16127100

  7. Biostability and biocompatibility of modified polyurethane elastomers

    NASA Astrophysics Data System (ADS)

    Christenson, Elizabeth Marie

    Several strategies have been employed to increase the biostability of medical grade polyurethanes while maintaining the desirable properties of current poly(ether urethanes). It was hypothesized that polyurethane surface chemistry controls biodegradation/biostability that can lead to ultimate failure/success of these materials in clinical applications. Chemical modification or replacement of the susceptible soft segment was evaluated as a design strategy to increase the biostability of medical grade polyurethanes. The effect of soft segment chemistry on the phase morphology, mechanical properties and in vivo response of commercial polyurethanes were compared. Poly(ether urethane) (PEU), silicone-modified poly(ether urethane) (PEU-S), poly(carbonate urethane) (PCU) and silicone-modified poly(carbonate urethane) (PCU-S) elastomers were investigated. AFM phase imaging indicated that the overall two-phase morphology of poly(ether urethanes), necessary for its thermoplastic elastomeric properties, was not disrupted by changing the soft segment chemistry. All of the polyurethanes exhibited thermoplastic elastomeric behavior similar to that of the poly(ether urethane). Following material characterization, the biocompatibility of the polyurethane elastomers was evaluated using a subcutaneous cage implant protocol. All of the polyurethanes tested retained the excellent biocompatibility typical of poly(ether urethane) elastomers. Overall, the candidate polyurethanes were concluded to be suitable replacements of current poly(ether urethane) elastomers in medical applications. The results from the cage implant study and cell culture experiments indicated that monocytes adhere, differentiate and fuse to form foreign body giant cells (FBGCs) on all of the polyurethane specimens. It is now generally accepted that the reactive oxygen species released by these adherent macrophages and FBGCs initiate PEU biodegradation. ATR-FTIR analysis of explanted samples provided evidence of

  8. [Biological investigation of kinin-mediated angioedema].

    PubMed

    Defendi, F; Charignon, D; Ghannam, A; Ponard, D; Drouet, C

    2015-03-01

    Kinin-mediated angioedema results from accumulation of kinins, vasoactive and vasopermeant peptides, on the vascular endothelium. The disease is characterized by sudden episodes of swelling in the subcutaneous and submucosal tissues; the edema may occur spontaneously or it may be precipitated by triggering factors such as physical or emotional stress, or certain medicines. The characterization of kinin formation and catabolism systems helps improve knowledge of the aetiopathogenic mechanisms involved and provides the basis for classification of kinin-mediated angioedema conditions; thus, we may distinguish between angioedema with C1 inhibitor deficiency, whether inherited or acquired, and angioedema with normal C1 inhibitor activity, associated with increased kinin-forming activity or deficiency in kinin catabolism enzymes. In support of the clinical diagnosis, the physician may request laboratory investigation for a functional and molecular definition of the disease. Laboratory diagnosis is based on the characterization of: (1) kinin production control by C1 inhibitor investigation (function, antigen levels and circulating species); (2) kinin production (kininogenase activity, kininogen cleavage species); and (3) kinin catabolism enzymes (aminopeptidase P, carboxypeptidase N, angiotensin-I converting enzyme and dipeptidyl peptidase IV). An abnormal biological phenotype is supported by examination of susceptibility genes (SERPING1, F12 and XPNPEP2) and mutation segregation in the families. PMID:25683013

  9. PMN-kinin and kinin metabolizing enzymes in normal and malignant leucocytes.

    PubMed

    Greenbaum, L M; Freer, R; Chang, J; Semente, G; Yamafuji, K

    1969-07-01

    1. Studies have been carried out on the kinin-forming and kinin destroying activity of rabbit macrophages obtained from the lung before and after BCG injection and from the peritoneal cavity following mineral oil injection. A similar study was carried out with L-1210 leukaemic cells obtained from the peritoneal cavity of mice.2. The macrophages and leukaemic cells contain enzymes that form kinins from purified kininogen substrates at acid pH. The kinin-forming activity is not limited to the lysosomal fraction of the cell since it is found in extralysosomal compartments. Delta-guanidovaleryl benzyl ester partially inhibits the kinin-forming activity. Trasylol does not inhibit the kinin-forming activity of these cells, but does inhibit the kininases of these cells. The lack of effectiveness of this agent as a general anti-inflammatory agent is thus explained.3. The kininases of the normal and malignant cells are also inhibited by chloromethyl ketones such as tosyl-lysine chloromethyl ketone (TLCK) and tosyl-phenylalanine-chloromethyl ketone (TPCK) as well as by copper salts. Hydroxyquinoline has no inhibitory action on these cells, indicating that they differ from the plasma kininases.4. Investigation of the kinins produced by enzymes in rabbit and human polymorphonuclear (PMN) cells has demonstrated the formation of a kinin that differs from bradykinin and other known mammalian kinins in its pharmacological properties, molecular weight, and amino-terminal end group. This peptide has been named PMN-kinin.5. Overall, the investigation has demonstrated the importance of white cells in contributing to the formation and destruction of "extra-plasma" sources of kinins by enzymes which differ from plasma enzymes. Anti-inflammatory agents may have different actions on these cell enzymes from those on plasma enzymes. PMID:5305988

  10. Biostability of an implantable glucose sensor chip

    NASA Astrophysics Data System (ADS)

    Fröhlich, M.; Birkholz, M.; Ehwald, K. E.; Kulse, P.; Fursenko, O.; Katzer, J.

    2012-12-01

    Surface materials of an implantable microelectronic chip intended for medical applications were evaluated with respect to their long-term stability in bio-environments. The sensor chip shall apply in a glucose monitor by operating as a microviscosimeter according to the principle of affinity viscosimetry. A monolithic integration of a microelectromechanical system (MEMS) into the sensor chip was successfully performed in a combined 0.25 μm CMOS/BiCMOS technology. In order to study material durability and biostability of the surfaces, sensor chips were exposed to various in vitro and in vivo tests. Corrosional damage of SiON, SiO2 and TiN surfaces was investigated by optical microscopy, ellipsometry and AFM. The results served for optimizing the Back-end-of-Line (BEoL) stack, from which the MEMS was prepared. Corrosion of metal lines could significantly be reduced by improving the topmost passivation layer. The experiments revealed no visible damage of the actuator or other functionally important MEMS elements. Sensor chips were also exposed to human body fluid for three month by implantation into the abdomen of a volunteer. Only small effects were observed for layer thickness and Ra roughness after explantation. In particular, TiN as used for the actuator beam showed no degradation by biocorrosion. The highest degradation rate of about 50 nm per month was revealed for the SiON passivation layer. These results suggest that the sensor chip may safely operate in subcutaneous tissue for a period of several months.

  11. Biostability of micro-photodiode arrays for subretinal implantation.

    PubMed

    Hämmerle, Hugo; Kobuch, Karin; Kohler, Konrad; Nisch, Wilfried; Sachs, Helmut; Stelzle, Martin

    2002-02-01

    Micro-photodiode arrays based on semiconductor chip technology are being developed to replace degenerated photoreceptor cells in the retina. Electric current is generated in tiny micro-photodiodes and delivered to the adjacent tissue by micro-electrodes. One of the main requirements of a sub-retinal implantable device is long-term stability versus corrosion in vivo (biostability). Biostability of micro-photodiode arrays (MPDA) was investigated in vitro and in vivo. No significant damage was found on chips immersed for up to 21 months in saline solution. Under in vivo conditions, however, the silicon oxide passivation layer of the chip was dissolved within a period of about 6-12 months. Subsequently, the underlying silicon was corroded. In contrast, stimulation electrodes consisting of titanium nitride were well preserved both in vitro and in vivo. The deterioration of the electrical properties of the micro-photodiodes correlated with the morphological damage observed. Strategies aiming at the development of an improved biostable encapsulation of neurotechnological implants have to be investigated and will be discussed briefly. PMID:11771699

  12. A review of the biostability and carcinogenicity of polyurethanes in medicine and the new generation of 'biostable' polyurethanes.

    PubMed

    Pinchuk, L

    1994-01-01

    Polyurethanes are very versatile materials which have been used in the body for over 20 years. In fact, there are probably more scientific papers describing these materials and modifications of these materials for medical use than any other material to date. Unfortunately, some formulations of these polymers are subject to biodegradation and have limited their application in the body. Extensive investigation of the biodegradation mechanisms of these polymers by many researchers in the field has led to the development of a new generation of what are now called 'biostable' polyurethanes. This article reviews the history of polyurethane in medicine, polyurethane nomenclature, the biodegradation of these materials, the proposed mechanisms of its degradation as well as the carcinogenicity associated with these materials. Included in the discussion are the polyurethanes used as pacemaker lead insulators as well as those used to coat breast implants. The article concludes with a review of the new generation of 'biostable' polyurethanes and their proposed formulations. PMID:7986779

  13. The biostability of silicone rubbers, a polyamide, and a polyester.

    PubMed

    Roggendorf, E

    1976-01-01

    A biostability test program was designed after evaluation of the relevant literature on in vivo aging phenomena in plastics and elastomers. The program comprised macroscopic, microscopic, mechanical, and physicochemical investigations. Five silicone rubbers, one polyester, and one polyamid were tested as to their aging behavior and their suitability for long-term implantation in the human body was assessed. In order to be able to state the applicability of materials used for endotheses, the various aging phenomena had to be divided into three groups, viz. unspecific, relative, and absolute indications of aging or unserviceability. Changes due to aging were found in all types of implanted plastics and elastomers. Thus, the formation of layers on inlay surfaces occurred regularly and the same would apply to changes in mechanical characteristics during the tensile test. Aging processes resulting in total unserviceability were fragmentation and crazing in the polyester and polyamide sheetings. Other aging phenomena which will easily fit into the classification given above are changes in electrical test values, protein, and lipid depositions without stronger absorptive adhesion, crystallizations on the surface of silicone vulcanizates, and chemical changes in the polyester and polyamide sheetings. Following the assessment of the materials used for endotheses, the test methods used have been evaluated with regard to their suitability for the testing of biostability. PMID:1249086

  14. Biostable multi-Aib analogs of tachykinin-related peptides demonstrate potent oral aphicidal activity in the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae).

    PubMed

    Nachman, Ronald J; Mahdian, Kamran; Nässel, Dick R; Isaac, R Elwyn; Pryor, Nan; Smagghe, Guy

    2011-03-01

    The tachykinin-related peptides (TRPs) are multifunctional neuropeptides found in a variety of arthropod species, including the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae). Two new biostable TRP analogs containing multiple, sterically hindered Aib residues were synthesized and found to exhibit significantly enhanced resistance to hydrolysis by angiotensin converting enzyme and neprilysin, membrane-bound enzymes that degrade and inactivate natural TRPs. The two biostable analogs were also found to retain significant myostimulatory activity in an isolated cockroach hindgut preparation, the bioassay used to isolate and identify the first members of the TRP family. Indeed one of the analogs (Leuma-TRP-Aib-1) matched the potency and efficacy of the natural, parent TRP peptide in this myotropic bioassay. The two biostable TRP analogs were further fed in solutions of artificial diet to the pea aphid over a period of 3 days and evaluated for antifeedant and aphicidal activity and compared with the effect of treatment with three natural, unmodified TRPs. The two biostable multi-Aib TRP analogs were observed to elicit aphicidal effects within the first 24 h. In contrast natural, unmodified TRPs, including two that are native to the pea aphid, demonstrated little or no activity. The most active analog, double-Aib analog Leuma-TRP-Aib-1 (pEA[Aib]SGFL[Aib]VR-NH(2)), featured aphicidal activity calculated at an LC(50) of 0.0083 nmol/μl (0.0087 μg/μl) and an LT(50) of 1.4 days, matching or exceeding the potency of commercially available aphicides. The mechanism of this activity has yet to be established. The aphicidal activity of the biostable TRP analogs may result from disruption of digestive processes by interfering with gut motility patterns and/or with fluid cycling in the gut; processes shown to be regulated by the TRPs in other insects. These active TRP analogs and/or second generation analogs offer potential as environmentally friendly pest aphid control agents

  15. Kinin receptor expression during Staphylococcus aureus infection

    PubMed Central

    Bengtson, Sara H.; Phagoo, Stephen B.; Norrby-Teglund, Anna; Påhlman, Lisa; Mörgelin, Matthias; Zuraw, Bruce L.; Leeb-Lundberg, L. M. Fredrik; Herwald, Heiko

    2006-01-01

    An inappropriate host response to invading bacteria is a critical parameter that often aggravates the outcome of an infection. Staphylococcus aureus is a major human Gram-positive pathogen that causes a wide array of community- and hospital-acquired diseases ranging from superficial skin infections to severe conditions such as staphylococcal toxic shock. Here we find that S aureus induces inflammatory reactions by modulating the expression and response of the B1 and B2 receptors, respectively. This process is initiated by a chain of events, involving staphylococcal-induced cytokine release from monocytes, bacteria-triggered contact activation, and conversion of bradykinin to its metabolite desArg9bradykinin. The data of the present study implicate an important and previously unknown role for kinin receptor regulation in S aureus infections. PMID:16735595

  16. EXTRACTION, RECOVERY, AND BIOSTABILITY OF EDTA FOR REMEDIATION OF HEAVY METAL-CONTAMINATED SOIL. (R825549C052)

    EPA Science Inventory

    Chelation removal of heavy metals from contaminated soil is seen as a viable remediation technique. A useful chelating agent should be strong, reusable, and biostable during metal extraction and recovery operations. This work tested the extraction, recovery, and biostability o...

  17. The kallikrein-kinin system in diabetic retinopathy.

    PubMed

    Bhat, Menakshi; Pouliot, Mylène; Couture, Réjean; Vaucher, Elvire

    2014-01-01

    Diabetic retinopathy (DR) is a major microvascular complication associated with type 1 and type 2 diabetes mellitus, which can lead to visual impairment and blindness. Current treatment strategies for DR are mostly limited to laser therapies, steroids, and anti-VEGF agents, which are often associated with unwanted side effects leading to further complications. Recent evidence suggests that kinins play a primary role in the development of DR through enhanced vascular permeability, leukocytes infiltration, and other inflammatory mechanisms. These deleterious effects are mediated by kinin B1 and B2 receptors, which are expressed in diabetic human and rodent retina. Importantly, kinin B1 receptor is virtually absent in sane tissue, yet it is induced and upregulated in diabetic retina. These peptides belong to the kallikrein-kinin system (KKS), which contains two separate and independent pathways of regulated serine proteases, namely plasma kallikrein (PK) and tissue kallikrein (TK) that are involved in the biosynthesis of bradykinin (BK) and kallidin (Lys-BK), respectively. Hence, ocular inhibition of kallikreins or antagonism of kinin receptors offers new therapeutic avenues in the treatment and management of DR. Herein, we present an overview of the principal features and known inflammatory mechanisms associated with DR along with the current therapeutic approaches and put special emphasis on the KKS as a new and promising therapeutic target due to its link with key pathways directly associated with the development of DR. PMID:25130041

  18. Glutaraldehyde-induced remineralization improves the mechanical properties and biostability of dentin collagen.

    PubMed

    Chen, Chaoqun; Mao, Caiyun; Sun, Jian; Chen, Yi; Wang, Wei; Pan, Haihua; Tang, Ruikang; Gu, Xinhua

    2016-10-01

    The purpose of this study was to induce a biomimetic remineralization process by using glutaraldehyde (GA) to reconstruct the mechanical properties and biostability of demineralized collagen. Demineralized dentin disks (35% phosphoric acid, 10s) were pretreated with a 5% GA solution for 3min and then cultivated in a calcium phosphate remineralization solution. The remineralization kinetics and superstructure of the remineralization layer were evaluated by Raman spectroscopy, transmission electron microscopy, scanning electron microscopy and nanoindentation tests. The biostability was examined by enzymatic degradation experiments. A significant difference was found in dentin remineralization process between dentin with and without GA pretreating. GA showed a specific affinity to dentin collagen resulting in the formation of a cross-linking superstructure. GA pretreating could remarkably shorten remineralization time from 7days to 2days. The GA-induced remineralized collagen fibrils were well encapsulated by newly formed hydroxyapatite mineral nanocrystals. With the nano-hydroxyapatite coating, both the mechanical properties (elastic modulus and hardness) and the biostability against enzymatic degradation of the collagen were significantly enhanced, matching those of natural dentin. The results indicated that GA cross-linking of dentin collagen could promote dentin biomimetic remineralization, resulting in an improved mechanical properties and biostability. It may provide a promising tissue-engineering technology for dentin repair. PMID:27287165

  19. Kallikrein-kinin system in the plasma of snakes.

    PubMed

    Picarelli, Z P; Prezoto, B C; Hiraichi, E; Abdalla, F M

    1992-01-01

    Using pharmacological preparations suitable for assay of mammalian kinins, it was shown that Bothrops jararaca (Bj) venom and other kininogenases were unable to release kinins from snake plasma. The kallikrein-kinin system presents species-specificity in birds. In order to detect such a specificity in snakes, the effects of Bj venom on snake blood pressure and the effect of incubates of snake plasma with trypsin, on snake blood pressure and snake uterus, were studied. The possibility of activating snake plasma kallikrein with ellagic acid, glass beads or kaolin was also investigated. Whereas plasma of the snakes Waglerophis merremii (Wm) and Crotalus durissus (Cd), were shown to contain factor XII, prekallikrein, kininogen, kininases and to present a low but definite activation rate of the kinin system, the plasmas of Bj, Bothrops mojeni (Bm) and Oxyrophus trigeminus (Ot), yielded only kininogen and kininases. Activation of the system was not even detected by the sensitive substrate Ac-Phe-Arg-Nan (acetyl-phenylalanyl-arginyl-4nitro-anilide), indicating that the plasma of these species does not possess either factor XII and/or prekallikrein. Snake plasma may constitute an interesting model for the study of blood clotting, fibrinolytic and complement systems. PMID:1609651

  20. The corticotropin-releasing factor-like diuretic hormone 44 (DH44) and kinin neuropeptides modulate desiccation and starvation tolerance in Drosophila melanogaster.

    PubMed

    Cannell, Elizabeth; Dornan, Anthony J; Halberg, Kenneth A; Terhzaz, Selim; Dow, Julian A T; Davies, Shireen-A

    2016-06-01

    Malpighian tubules are critical organs for epithelial fluid transport and stress tolerance in insects, and are under neuroendocrine control by multiple neuropeptides secreted by identified neurons. Here, we demonstrate roles for CRF-like diuretic hormone 44 (DH44) and Drosophila melanogaster kinin (Drome-kinin, DK) in desiccation and starvation tolerance. Gene expression and labelled DH44 ligand binding data, as well as highly selective knockdowns and/or neuronal ablations of DH44 in neurons of the pars intercerebralis and DH44 receptor (DH44-R2) in Malpighian tubule principal cells, indicate that suppression of DH44 signalling improves desiccation tolerance of the intact fly. Drome-kinin receptor, encoded by the leucokinin receptor gene, LKR, is expressed in DH44 neurons as well as in stellate cells of the Malpighian tubules. LKR knockdown in DH44-expressing neurons reduces Malpighian tubule-specific LKR, suggesting interactions between DH44 and LK signalling pathways. Finally, although a role for DK in desiccation tolerance was not defined, we demonstrate a novel role for Malpighian tubule cell-specific LKR in starvation tolerance. Starvation increases gene expression of epithelial LKR. Also, Malpighian tubule stellate cell-specific knockdown of LKR significantly reduced starvation tolerance, demonstrating a role for neuropeptide signalling during starvation stress. PMID:26896569

  1. The single kinin receptor signals to separate and independent physiological pathways in Malpighian tubules of the yellow fever mosquito

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the past we have used the leucokinins, the kinins of the cockroach Leucophaea, to evaluate the mechanism of diuretic action of kinin peptides in Malpighian tubules of the yellow fever mosquito Aedes aegypti. Now using aedeskinins, the kinins of Aedes, are available, we find that in isolated Aede...

  2. Biostability and macrophage-mediated foreign body reaction of silicone-modified polyurethanes.

    PubMed

    Christenson, Elizabeth M; Dadsetan, Mahrokh; Hiltner, Anne

    2005-08-01

    In this study, the effect of soft segment chemistry on the phase morphology and in vivo response of commercial-grade poly(ether urethane) (PEU), silicone-modified PEU (PEU-S), poly(carbonate urethane) (PCU), and silicone-modified PCU (PCU-S) elastomers were examined. Silicone-modified polyurethanes were developed to combine the biostability of silicone with the mechanical properties of PEUs. Results from the infrared spectroscopy confirmed the presence of silicone at the surface of the PEU-S and PCU-S films. Atomic force microscopy phase imaging indicated that the overall two-phase morphology of PEUs, necessary for its thermoplastic elastomeric properties, was not disrupted by the silicone modification. After material characterization, the in vivo foreign body response and biostability of the polyurethanes were studied using a subcutaneous cage implant protocol. The results from the cage implant study indicated that monocytes adhere, differentiate to macrophages which fuse to form foreign body giant cells on all of the polyurethanes. However, the silicone-modified surfaces promoted apoptosis of adherent macrophages at 4 days and high levels of macrophage fusion after 21 days. These results confirm that the surface of a biomaterial may influence the induction of apoptosis of adherent macrophages in vivo and are consistent with previous cell culture studies of these materials. This study validates the use of our standard cell culture protocol to predict in vivo behavior and further supports the hypothesis that interleukin-4 is the primary mediator of macrophage fusion and foreign body giant cell formation in vivo. The impact of these findings on the biostability of polyurethanes is the subject of current investigations. Attenuated total reflectance-Fourier transform infrared analysis of explanted specimens provided evidence of chain scission and crosslinking at the surface of all of the polyurethanes. The silicone modification did not fully inhibit the oxidative

  3. Surface modification of poly(ether urethane urea) with modified dehydroepiandrosterone for improved in vivo biostability.

    PubMed

    Christenson, Elizabeth M; Wiggins, Michael J; Anderson, James M; Hiltner, Anne

    2005-04-01

    In this study, a fatty acid urethane derivative of dehydroepiandrosterone (DHEA) was synthesized and evaluated as a polyurethane additive to increase long-term biostability. The modification was hypothesized to reduce the water solubility of the DHEA and physically anchor the additive in the polyurethane during implantation. Polyurethane film weight loss in water as a function of time was studied to determine the polymer retention of the modified DHEA. The polyurethane film with unmodified DHEA had significant weight loss in the first day (10%) that was previously correlated to rapid leaching of the additive. The polyurethane film with modified DHEA had significantly less weight loss at all time points indicating improved polymer retention. The effect of the modified DHEA additive on the biostability of a poly(ether urethane urea) was examined after 5 weeks of subcutaneous implantation in Sprague-Dawley rats. Optical micrographs and infrared analysis of the specimens indicated that the modified DHEA bloomed to the surface of the film forming a crystalline surface layer approximately 10-15 microns thick. After explantation, this surface layer was intact without measurable differences in surface chemistry as monitored by attenuated total reflectance-Fourier transform infrared spectroscopy. There was no evidence of degradation of the polyurethane underneath the modified DHEA surface layer as compared with the polyurethane control. We have concluded that the modified DHEA self-assembled into a protective surface coating that inhibited degradation of the polyurethane. The roughness of the modified DHEA surface layer prevented adherent cell analysis to determine if the additive retained the ability to down-regulate macrophage activity. Subsequent studies will investigate the ability of surface-modifying additives to modulate cellular respiratory bursts in addition to the formation of an impermeable barrier. This bimodal approach to improving biostability holds great

  4. Biostability and biocompatibility of poly(ester urethane)-gold nanocomposites.

    PubMed

    Hsu, Shan-hui; Tang, Cheng-Ming; Tseng, Hsiang-Jung

    2008-11-01

    Nanocomposites from a polyester-type water-borne polyurethane (PU) containing different amounts (17.4-174 ppm) of gold (Au) nanoparticles (approximately 5 nm) were prepared. A previous study has shown that the Au nanoparticles could induce surface morphological transformations in the PU (e.g. the mesophase transition from hard lamellae to soft micelles), which modify the physicochemical properties of the PU as well as the fibroblast response to the PU. The current study focused on the biostability and biocompatibility of the nanocomposites. The nanocomposites were characterized by transmission electron microscopy and X-ray photoelectron spectroscopy, and their oxidative stability and free radical scavenging ability were tested. The inflammatory response was evaluated by monocyte activation in vitro and rat subcutaneous implantation in vivo. It was found that the nanocomposites containing 43.5-65 ppm of Au had the least monocyte activation and tissue reactions. PU and the nanocomposites were rather resistant to oxidative degradation in vitro and biodegradation in vivo. The nanocomposites exhibited greater free radical scavenging abilities than the original PU. Based on the above results, the significantly enhanced biocompatibility of the PU-Au nanocomposites with 43.5-65 ppm of gold over the original PU appeared to be a result of the extensively modified surface morphology and greater free radical scavenging ability, instead of due to the difference in biostability. PMID:18657493

  5. Cultured human synovial fibroblasts rapidly metabolize kinins and neuropeptides.

    PubMed Central

    Bathon, J M; Proud, D; Mizutani, S; Ward, P E

    1992-01-01

    Kinins and substance P have been implicated in the pathogenesis of inflammatory arthritis by virtue of their abilities to induce vasodilation, edema, and pain. The relative biological potencies of these peptides in vivo would depend at least in part upon their rates of catabolism in the joint. We hypothesized that human synovial lining cells may regulate intraarticular levels of kinins and neuropeptides via degradation by cell surface-associated peptidases. We exposed intact human synovial fibroblasts to kinins and substance P, in the presence or absence of specific peptidase inhibitors, and measured the amount of intact substrate remaining and degradation product(s) generated over time. Aminopeptidase M (AmM; EC 3.4.11.2), neutral endopeptidase-24.11 (NEP-24.11; EC 3.4.24.11), and dipeptidyl(amino)peptidase IV (DAP IV; EC 3.4.14.5) were identified on the cell surface of synovial cells. Bradykinin degradation was due entirely to NEP-24.11 (1.39 +/- 0.29 nmol/min per well). Lysylbradykinin was also degraded by NEP-24.11 (0.80 +/- 0.19 nmol/min per well); however, in the presence of phosphoramidon, AmM-mediated conversion to bradykinin (3.74 +/- 0.46 nmol/min per well) could be demonstrated. The combined actions of NEP-24.11 (0.93 +/- 0.15 nmol/min per well) and DAP IV (0.84 +/- 0.18 nmol/min per well) were responsible for the degradation of substance P. AmM (2.44 +/- 0.33 nmol/min per well) and NEP-24.11 (1.30 +/- 0.45 nmol/min per well) were responsible for the degradation of the opioid peptide, [Leu5]enkephalin. The identity of each of the three peptidases was confirmed via synthetic substrate hydrolysis, inhibition profile, and immunological identification. The profiles of peptidase enzymes identified in cells derived from rheumatoid and osteoarthritic joints were identical. These data demonstrate the human synovial fibroblast to be a rich source of three specific peptidases and suggest that it may play a prominent role in regulating peptide levels in the joint

  6. Strong and Biostable Hyaluronic Acid-Calcium Phosphate Nanocomposite Hydrogel via in Situ Precipitation Process.

    PubMed

    Jeong, Seol-Ha; Koh, Young-Hag; Kim, Suk-Wha; Park, Ji-Ung; Kim, Hyoun-Ee; Song, Juha

    2016-03-14

    Hyaluronic acid (HAc) hydrogel exhibits excellent biocompatibility, but it has limited biomedical application due to its poor biomechanical properties as well as too-fast enzymatic degradation. In this study, we have developed an in situ precipitation process for the fabrication of a HAc-calcium phosphate nanocomposite hydrogel, after the formation of the glycidyl methacrylate-conjugated HAc (GMHA) hydrogels via photo-cross-linking, to improve the mechanical and biological properties under physiological conditions. In particular, our process facilitates the rapid incorporation of calcium phosphate (CaP) nanoparticles of uniform size and with minimal agglomeration into a polymer matrix, homogeneously. Compared with pure HAc, the nanocomposite hydrogels exhibit improved mechanical behavior. Specifically, the shear modulus is improved by a factor of 4. The biostability of the nanocomposite hydrogel was also significantly improved compared with that of pure HAc hydrogels under both in vitro and in vivo conditions. PMID:26878437

  7. The Kallikrein-Kinin System as a Regulator of Cardiovascular and Renal Function

    PubMed Central

    Rhaleb, Nour-Eddine; Yang, Xiao-Ping; Carretero, Oscar A.

    2015-01-01

    Autocrine, paracrine, endocrine, and neuroendocrine hormonal systems help regulate cardiovascular and renal function. Any change in the balance among these systems may result in hypertension and target organ damage, whether the cause is genetic, environmental or a combination of the two. Endocrine and neuroendocrine vasopressor hormones such as the renin-angiotensin system (RAS), aldosterone, and catecholamines are important for regulation of blood pressure and pathogenesis of hypertension and target organ damage. While the role of vasodepressor autacoids such as kinins is not as well defined, there is increasing evidence that they are not only critical to blood pressure and renal function but may also oppose remodeling of the cardiovascular system. Here we will primarily be concerned with kinins, which are oligopeptides containing the aminoacid sequence of bradykinin. They are generated from precursors known as kininogens by enzymes such as tissue (glandular) and plasma kallikrein. Some of the effects of kinins are mediated via autacoids such as eicosanoids, nitric oxide (NO), endothelium-derived hyperpolarizing factor (EDHF), and/or tissue plasminogen activator (†PA). Kinins help protect against cardiac ischemia and play an important part in preconditioning as well as the cardiovascular and renal protective effects of angiotensin-converting enzyme (ACE) and angiotensin type 1 receptor blockers (ARB). But the role of kinins in the pathogenesis of hypertension remains controversial. A study of Utah families revealed that a dominant kallikrein gene expressed as high urinary kallikrein excretion was associated with a decreased risk of essential hypertension. Moreover, researchers have identified a restriction fragment length polymorphism (RFLP) that distinguishes the kallikrein gene family found in one strain of spontaneously hypertensive rats (SHR) from a homologous gene in normotensive Brown Norway rats, and in recombinant inbred substrains derived from these SHR

  8. In vitro biostability of poly(dimethyl siloxane/hexamethylene oxide)-based polyurethane/layered silicate nanocomposites.

    PubMed

    Andriani, Yosephine; Morrow, Isabel C; Taran, Elena; Edwards, Grant A; Schiller, Tara L; Osman, Azlin F; Martin, Darren J

    2013-09-01

    We have prepared a number of silicone-based thermoplastic polyurethane (TPU) nanocomposites and demonstrated an enhancement of in vitro biostability against metal-ion-induced oxidation for potential use in long-term implantable medical devices. Organoclays based on both low-aspect-ratio hectorites and high-aspect-ratio fluoromicas were evaluated after being dual-modified with two quaternary alkyl ammonium salts with differing degrees of polarity. The resultant nanocomposites were tested for in vitro biostability using physiologically relevant oxidizing conditions. Subsequently, the effects of oxidative treatment on the surface degradation and bulk mechanical integrity of the nanocomposites were investigated and compared with the parent TPUs to identify nanocomposites with the most desirable features for long-term implantation. Here, we demonstrate that the low-aspect-ratio organohectorite was delaminated and well dispersed in the nanocomposites. Importantly, these factors gave rise to the enhanced oxidative stability. In addition, the mechanical properties of all nanocomposites were less adversely affected by the oxidative treatment compared to their parent TPUs. These results suggest the potential for improved mechanical integrity and biostability when suitable dual modified organoclays are incorporated in a silicone-based TPU. PMID:23727246

  9. Leptin deficiency leads to the regulation of kinin receptors expression in mice.

    PubMed

    Abe, Karina Camasmie; Mori, Marcelo Alves da Silva; Pesquero, Joao Bosco

    2007-02-01

    Kinins are vasoactive and pro-inflammatory peptides generated by the cleavage of the kininogen by kallikreins. Two kinin receptors have been described and denominated B1 and B2. Obesity frequently accompanies other pathologies, such as diabetes and hypertention. The clustering of these pathologies is usually known as "metabolic syndrome". Mice lacking leptin gene (ob/ob) are severely obese and hyperphagic. Using quantitative RT-PCR analysis of B1 and B2 mRNAs expression, we described for the first time a correlation between the kallikrein-kinin system (KKS) and severe obesity in mice. The ob/ob mice presented lower expression of B2 mRNA in the white adipose tissue (WAT) and hypothalamus, both primary sites for neuroendocrine regulation of the energetic metabolism. B1 mRNA, however, is overexpressed in these tissues of ob/ob mice. An upregulation of the B1 mRNA has also been seen in liver, abdominal aorta and stomach fundus. However, different from the lean mice, the expression of the B1 mRNA in brown adipose tissue (BAT) and heart is completely abolished. Our data show that kinin receptors are differently modulated in distinct tissues in obesity. These findings suggest a connection between the KKS and obesity, and suggest that kinin receptors could be involved in the ethiopathogenesis of the metabolic syndrome. PMID:17184856

  10. The single kinin receptor signals to separate and independent physiological pathways in Malpighian tubules of the yellow fever mosquito

    PubMed Central

    Schepel, Stephen A.; Fox, Andrew J.; Miyauchi, Jeremy T.; Sou, Tiffany; Yang, Jason D.; Lau, Kenneth; Blum, Austin W.; Nicholson, Linda K.; Tiburcy, Felix; Nachman, Ronald J.; Piermarini, Peter M.

    2010-01-01

    In the past, we have used the kinins of the cockroach Leucophaea (the leucokinins) to evaluate the mechanism of diuretic action of kinin peptides in Malpighian tubules of the yellow fever mosquito Aedes aegypti. Now using the kinins of Aedes (the aedeskinins), we have found that in isolated Aedes Malpighian tubules all three aedeskinins (1 μM) significantly 1) increased the rate of fluid secretion (V̇S), 2) hyperpolarized the basolateral membrane voltage (Vbl), and 3) decreased the input resistance (Rin) of principal cells, consistent with the known increase in the Cl− conductance of the paracellular pathway in Aedes Malpighian tubules. Aedeskinin-III, studied in further detail, significantly increased V̇S with an EC50 of 1.5 × 10−8 M. In parallel, the Na+ concentration in secreted fluid significantly decreased, and the K+ concentration significantly increased. The concentration of Cl− remained unchanged. While the three aedeskinins triggered effects on Vbl, Rin, and V̇S, synthetic kinin analogs, which contain modifications of the COOH-terminal amide pentapeptide core sequence critical for biological activity, displayed variable effects. For example, kinin analog 1578 significantly stimulated V̇S but had no effect on Vbl and Rin, whereas kinin analog 1708 had no effect on V̇S but significantly affected Vbl and Rin. These observations suggest separate signaling pathways activated by kinins. One triggers the electrophysiological response, and the other triggers fluid secretion. It remains to be determined whether the two signaling pathways emanate from a single kinin receptor via agonist-directed signaling or from a differentially glycosylated receptor. Occasionally, Malpighian tubules did not exhibit a detectable response to natural and synthetic kinins. Hypothetically, the expression of the kinin receptor may depend on developmental, nutritional, and/or reproductive signals. PMID:20538895

  11. Kinin receptor agonism restores hindlimb postischemic neovascularization capacity in diabetic mice.

    PubMed

    Desposito, Dorinne; Potier, Louis; Chollet, Catherine; Gobeil, Fernand; Roussel, Ronan; Alhenc-Gelas, Francois; Bouby, Nadine; Waeckel, Ludovic

    2015-02-01

    Limb ischemia is a major complication of thromboembolic diseases. Diabetes worsens prognosis by impairing neovascularization. Genetic or pharmacological inactivation of the kallikrein-kinin system aggravates limb ischemia in nondiabetic animals, whereas angiotensin I-converting enzyme/kininase II inhibition improves outcome. The role of kinins in limb ischemia in the setting of diabetes is not documented. We assessed whether selective activation of kinin receptors by pharmacological agonists can influence neovascularization in diabetic mice with limb ischemia and have a therapeutic effect. Selective pseudopeptide kinin B1 or B2 receptor agonists resistant to peptidase action were administered by osmotic minipumps at a nonhypotensive dosage for 14 days after unilateral femoral artery ligation in mice previously rendered diabetic by streptozotocin. Comparison was made with ligatured, nonagonist-treated nondiabetic and diabetic mice. Diabetes reduced neovascularization, assessed by microangiography and histologic capillary density analysis, by roughly 40%. B1 receptor agonist or B2 receptor agonist similarly restored neovascularization in diabetic mice. Neovascularization in agonist-treated diabetic mice was indistinguishable from nondiabetic mice. Both treatments restored blood flow in the ischemic hindfoot, measured by laser-Doppler perfusion imaging. Macrophage infiltration increased 3-fold in the ischemic gastrocnemius muscle during B1 receptor agonist or B2 receptor agonist treatment, and vascular endothelial growth factor (VEGF) level increased 2-fold. Both treatments increased, by 50-100%, circulating CD45/CD11b-positive monocytes and CD34(+)/VEGFR2(+) progenitor cells. Thus, selective pharmacological activation of B1 or B2 kinin receptor overcomes the effect of diabetes on postischemic neovascularization and restores tissue perfusion through monocyte/macrophage mobilization. Kinin receptors are potential therapeutic targets in limb ischemia in diabetes. PMID

  12. Long-term biostability of self-assembling protein polymers in the absence of covalent crosslinking.

    PubMed

    Sallach, Rory E; Cui, Wanxing; Balderrama, Fanor; Martinez, Adam W; Wen, Jing; Haller, Carolyn A; Taylor, Jeannette V; Wright, Elizabeth R; Long, Robert C; Chaikof, Elliot L

    2010-02-01

    Unless chemically crosslinked, matrix proteins, such as collagen or silk, display a limited lifetime in vivo with significant degradation observed over a period of weeks. Likewise, amphiphilic peptides, lipopeptides, or glycolipids that self-assemble through hydrophobic interactions to form thin films, fiber networks, or vesicles do not demonstrate in vivo biostability beyond a few days. We report herein that a self-assembling, recombinant elastin-mimetic triblock copolymer elicited minimal inflammatory response and displayed robust in vivo stability for periods exceeding 1 year, in the absence of either chemical or ionic crosslinking. Specifically, neither a significant inflammatory response nor calcification was observed upon implantation of test materials into the peritoneal cavity or subcutaneous space of a mouse model. Moreover, serial quantitative magnetic resonance imaging, evaluation of pre- and post-explant ultrastructure by cryo-high resolution scanning electron microscopy, and an examination of implant mechanical responses revealed substantial preservation of form, material architecture, and biomechanical properties, providing convincing evidence of a non-chemically or ionically crosslinked protein polymer system that exhibits long-term stability in vivo. PMID:19854505

  13. Human plasma kallikrein-kinin system: Physiological and biochemical parameters

    PubMed Central

    Bryant, J.W.; Shariat-Madar, z

    2016-01-01

    The plasma kallikrein-kinin system (KKS) plays a critical role in human physiology. The KKS encompasses coagulation factor XII (FXII), the complex of prekallikrein (PK) and high molecular weight kininogen (HK). The conversion of plasma to kallikrein by the activated FXII and in response to numerous different stimuli leads to the generation of bradykinin (BK) and activated HK (HKa, an antiangiogenic peptide). BK is a proinflammatory peptide, a pain mediator and potent vasodilator, leading to robust accumulation of fluid in the interstitium. Systemic production of BK, HKa with the interplay between BK bound-BK receptors and the soluble form of HKa are key to angiogenesis and hemodynamics. KKS has been implicated in the pathogenesis of inflammation, hypertension, endotoxemia, and coagulopathy. In all these cases increased BK levels is the hallmark. In some cases, the persistent production of BK due to the deficiency of the blood protein C1-inhibitor, which controls FXII, is detrimental to the survival of the patients with hereditary angioedema (HAE). In others, the inability of angiotensin converting enzyme (ACE) to degrade BK leads to elevated BK levels and edema in patients on ACE inhibitors. Thus, the mechanisms that interfere with BK liberation or degradation would lead to blood pressure dysfunction. In contrast, anti-kallikrein treatment could have adverse effects in hemodynamic changes induced by vasoconstrictor agents. Genetic models of kallikrein deficiency are needed to evaluate the quantitative role of kallikrein and to validate whether strategies designed to activate or inhibit kallikrein may be important for regulating whole-body BK sensitivity. PMID:19689262

  14. Improved biostability assessment of drinking water with a suite of test methods at a water supply treating eutrophic lake water.

    PubMed

    van der Kooij, Dick; Martijn, Bram; Schaap, Peter G; Hoogenboezem, Wim; Veenendaal, Harm R; van der Wielen, Paul W J J

    2015-12-15

    Assessment of drinking-water biostability is generally based on measuring bacterial growth in short-term batch tests. However, microbial growth in the distribution system is affected by multiple interactions between water, biofilms and sediments. Therefore a diversity of test methods was applied to characterize the biostability of drinking water distributed without disinfectant residual at a surface-water supply. This drinking water complied with the standards for the heterotrophic plate count and coliforms, but aeromonads periodically exceeded the regulatory limit (1000 CFU 100 mL(-1)). Compounds promoting growth of the biopolymer-utilizing Flavobacterium johnsoniae strain A3 accounted for c. 21% of the easily assimilable organic carbon (AOC) concentration (17 ± 2 μg C L(-1)) determined by growth of pure cultures in the water after granular activated-carbon filtration (GACF). Growth of the indigenous bacteria measured as adenosine tri-phosphate in water samples incubated at 25 °C confirmed the low AOC in the GACF but revealed the presence of compounds promoting growth after more than one week of incubation. Furthermore, the concentration of particulate organic carbon in the GACF (83 ± 42 μg C L(-1), including 65% carbohydrates) exceeded the AOC concentration. The increased biomass accumulation rate in the continuous biofouling monitor (CBM) at the distribution system reservoir demonstrated the presence of easily biodegradable by-products related to ClO2 dosage to the GACF and in the CBM at 42 km from the treatment plant an iron-associated biomass accumulation was observed. The various methods applied thus distinguished between easily assimilable compounds, biopolymers, slowly biodegradable compounds and biomass-accumulation potential, providing an improved assessment of the biostability of the water. Regrowth of aeromonads may be related to biomass-turnover processes in the distribution system, but establishment of quantitative relationships is needed for

  15. Limitations of predicting in vivo biostability of multiphase polyurethane elastomers using temperature-accelerated degradation testing.

    PubMed

    Padsalgikar, Ajay; Cosgriff-Hernandez, Elizabeth; Gallagher, Genevieve; Touchet, Tyler; Iacob, Ciprian; Mellin, Lisa; Norlin-Weissenrieder, Anna; Runt, James

    2015-01-01

    Polyurethane biostability has been the subject of intense research since the failure of polyether polyurethane pacemaker leads in the 1980s. Accelerated in vitro testing has been used to isolate degradation mechanisms and predict clinical performance of biomaterials. However, validation that in vitro methods reproduce in vivo degradation is critical to the selection of appropriate tests. High temperature has been proposed as a method to accelerate degradation. However, correlation of such data to in vivo performance is poor for polyurethanes due to the impact of temperature on microstructure. In this study, we characterize the lack of correlation between hydrolytic degradation predicted using a high temperature aging model of a polydimethylsiloxane-based polyurethane and its in vivo performance. Most notably, the predicted molecular weight and tensile property changes from the accelerated aging study did not correlate with clinical explants subjected to human biological stresses in real time through 5 years. Further, DMTA, ATR-FTIR, and SAXS experiments on samples aged for 2 weeks in PBS indicated greater phase separation in samples aged at 85°C compared to those aged at 37°C and unaged controls. These results confirm that microstructural changes occur at high temperatures that do not occur at in vivo temperatures. In addition, water absorption studies demonstrated that water saturation levels increased significantly with temperature. This study highlights that the multiphase morphology of polyurethane precludes the use of temperature accelerated biodegradation for the prediction of clinical performance and provides critical information in designing appropriate in vitro tests for this class of materials. PMID:24810790

  16. Long-term in vivo biostability of poly(dimethylsiloxane)/poly(hexamethylene oxide) mixed macrodiol-based polyurethane elastomers.

    PubMed

    Simmons, Anne; Hyvarinen, Jari; Odell, Ross A; Martin, Darren J; Gunatillake, Pathiraja A; Noble, Kathryn R; Poole-Warren, Laura A

    2004-09-01

    The long-term biostability of a novel thermoplastic polyurethane elastomer (Elast-Eon 2 80A) synthesized using poly(hexamethylene oxide) (PHMO) and poly(dimethylsiloxane) (PDMS) macrodiols has been studied using an in vivo ovine model. The material's biostability was compared with that of three commercially available control materials, Pellethane 2363-80A, Pellethane 2363-55D and Bionate 55D, after subcutaneous implantation of strained compression moulded flat sheet dumbbells in sheep for periods ranging from 3 to 24 months. Scanning electron microscopy, attenuated total reflectance-Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy were used to assess changes in the surface chemical structure and morphology of the materials. Gel permeation chromatography, differential scanning calorimetry and tensile testing were used to examine changes in bulk characteristics of the materials. The results showed that the biostability of the soft flexible PDMS-based test polyurethane was significantly better than the control material of similar softness, Pellethane 80A, and as good as or better than both of the harder commercially available negative control polyurethanes, Pellethane 55D and Bionate 55D. Changes observed in the surface of the Pellethane materials were consistent with oxidation of the aliphatic polyether soft segment and hydrolysis of the urethane bonds joining hard to soft segment with degradation in Pellethane 80A significantly more severe than that observed in Pellethane 55D. Very minor changes were seen on the surfaces of the Elast-Eon 2 80A and Bionate 55D materials. There was a general trend of molecular weight decreasing with time across all polymers and the molecular weights of all materials decreased at a similar relative rate. The polydispersity ratio, Mw/Mn, increased with time for all materials. Tensile tests indicated that UTS increased in Elast-Eon 2 80A and Bionate 55D following implantation under strained conditions

  17. A new class of pseudopeptide antagonists of the kinin B1 receptor containing alkyl spacers.

    PubMed

    Galoppini, C; Meini, S; Tancredi, M; Di Fenza, A; Triolo, A; Quartara, L; Maggi, C A; Formaggio, F; Toniolo, C; Mazzucco, S; Papini, A; Rovero, P

    1999-02-11

    Four previously reported kinin receptor peptide antagonists, including the B1 receptor-selective peptides desArg10-HOE 140 (H-D-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-D-Tic-Oic-OH) and B-9858 (H-Lys-Lys-Arg-Pro-Hyp-Gly-Igl-Ser-D-Igl-Oic-OH), have been modified by replacement of the central tetrapeptide Pro-Hyp-Gly-Xaa with linear alkyl spacers of variable length. The analogue of desArg10-HOE 140 containing the 11-aminoundecanoic acid as spacer, MEN 11575 [H-D-Arg-Arg-NH-(CH2)10-CO-Ser-D-Tic-Oic-OH], was found to be slightly more potent than the unmodified peptide (pA2 = 7.1) as a kinin B1 receptor antagonist in the rat ileum longitudinal smooth muscle assay. Moreover, MEN 11575 is devoid of residual agonist activity at the kinin B1 receptor (rat ileum) and antagonist activity at the kinin B2 receptor (guinea pig ileum longitudinal smooth muscle). Both these activities are displayed by the parent peptide desArg10-HOE 140. Therefore, despite its greatly simplified chemical structure, MEN 11575 shows an improved pharmacological profile in terms of both potency and selectivity, and it represents a good template for the development of new peptidomimetic kinin B1 receptor antagonists. We also report an attempt to investigate the conformational role of the flexible, linear spacer of MEN 11575 and to design more constrained analogues, possibly locked in the bioactive conformation, using semirigid spacers based on Calpha-tetrasubstituted alpha-amino acids of the family of 1-aminocycloalkane-1-carboxylic acids (Acnc). PMID:9986712

  18. In vivo biostability of polymeric spine implants: retrieval analyses from a United States investigational device exemption study.

    PubMed

    Shen, Ming; Zhang, Kai; Koettig, Petra; Welch, William C; Dawson, John M

    2011-11-01

    The Dynesys System for stabilizing the lumbar spine was first surgically implanted in Europe in 1994. In 2003, a prospective, randomized, investigational device exemption clinical trial of the system for non-fusion dynamic stabilization began. Polycarbonate urethane (PCU) and polyethylene terephthalate (PET) components explanted from four patients who had participated in the study were analyzed for biostability. Components had been implanted 9-19 months. The explanted components were visually inspected and digitally photographed. Scanning electron microscopy was used to analyze the surface of the spacers. The chemical and molecular properties of the retrieved spacers and cords were quantitatively compared with lot-matched, shelf-aged, components that had not been implanted using attenuated total reflection Fourier transform infrared (FTIR) and gel permeation chromatography (GPC). FTIR analyses suggested that the explanted spacers exhibited slight surface chemical changes but were chemically unchanged below the surface and in the center. New peaks that could be attributed to biodegradation of PCU were not observed. The spectral analyses for the cords revealed that the PET cords were chemically unchanged at both the surface and the interior. Peaks associated with the PET biodegradation were not detected. GPC results did not identify changes to the distributions of molecular weights that might be attributed to biodegradation of either PCU spacers or PET cords. The explanted condition of the retrieved components demonstrated the biostability of both PCU spacers and PET cords that had been in vivo for up to 19 months. PMID:21538208

  19. Biostable multi-Aib analogs of tachykinin-related peptides demonstrate potent oral aphicidal activity in the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The tachykinin-related peptides (TRPs) are multifunctional neuropeptides found in a variety of arthropod species, including the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae). Two novel biostable TRP analogs containing multiple, sterically-hindered Aib residues were synthesized and found to exhi...

  20. Nicotine impairs cyclooxygenase-2-dependent kinin-receptor-mediated murine airway relaxations

    SciTech Connect

    Xu, Yuan Cardell, Lars-Olaf

    2014-02-15

    Introduction: Cigarette smoke induces local inflammation and airway hyperreactivity. In asthmatics, it worsens the symptoms and increases the risk for exacerbation. The present study investigates the effects of nicotine on airway relaxations in isolated murine tracheal segments. Methods: Segments were cultured for 24 h in the presence of vehicle, nicotine (10 μM) and/or dexamethasone (1 μM). Airway relaxations were assessed in myographs after pre-contraction with carbachol (1 μM). Kinin receptors, cyclooxygenase (COX) and inflammatory mediator expressions were assessed by real-time PCR and confocal-microscopy-based immunohistochemistry. Results: The organ culture procedure markedly increased bradykinin- (selective B{sub 2} receptor agonist) and des-Arg{sup 9}-bradykinin- (selective B{sub 1} receptor agonist) induced relaxations, and slightly increased relaxation induced by isoprenaline, but not that induced by PGE{sub 2}. The kinin receptor mediated relaxations were epithelium-, COX-2- and EP2-receptor-dependent and accompanied by drastically enhanced mRNA levels of kinin receptors, as well as inflammatory mediators MCP-1 and iNOS. Increase in COX-2 and mPGES-1 was verified both at mRNA and protein levels. Nicotine selectively suppressed the organ-culture-enhanced relaxations induced by des-Arg{sup 9}-bradykinin and bradykinin, at the same time reducing mPGES-1 mRNA and protein expressions. α7-nicotinic acetylcholine receptor inhibitors α-bungarotoxin and MG624 both blocked the nicotine effects on kinin B{sub 2} receptors, but not those on B{sub 1}. Dexamethasone completely abolished kinin-induced relaxations. Conclusion: It is tempting to conclude that a local inflammatory process per se could have a bronchoprotective component by increasing COX-2 mediated airway relaxations and that nicotine could impede this safety mechanism. Dexamethasone further reduced airway inflammation together with relaxations. This might contribute to the steroid resistance seen in

  1. Deletion of Kinin B2 Receptor Alters Muscle Metabolism and Exercise Performance

    PubMed Central

    Reis, Felipe C. G.; Haro, Anderson S.; Bacurau, Aline V. N.; Hirabara, Sandro M.; Wasinski, Frederick; Ormanji, Milene S.; Moreira, José B. N.; Kiyomoto, Beatriz H.; Bertoncini, Clelia R. A.; Brum, Patricia C.; Curi, Rui; Bader, Michael; Bacurau, Reury F. P.; Pesquero, João B.; Araújo, Ronaldo C.

    2015-01-01

    Metabolic syndrome is a cluster of metabolic risk factors such as obesity, diabetes and cardiovascular diseases. Mitochondria is the main site of ATP production and its dysfunction leads to decreased oxidative phosphorylation, resulting in lipid accumulation and insulin resistance. Our group has demonstrated that kinins can modulate glucose and lipid metabolism as well as skeletal muscle mass. By using B2 receptor knockout mice (B2R-/-) we investigated whether kinin action affects weight gain and physical performance of the animals. Our results show that B2R-/- mice are resistant to high fat diet-induced obesity, have higher glucose tolerance as well as increased mitochondrial mass. These features are accompanied by higher energy expenditure and a lower feed efficiency associated with an increase in the proportion of type I fibers and intermediary fibers characterized by higher mitochondrial content and increased expression of genes related to oxidative metabolism. Additionally, the increased percentage of oxidative skeletal muscle fibers and mitochondrial apparatus in B2R-/- mice is coupled with a higher aerobic exercise performance. Taken together, our data give support to the involvement of kinins in skeletal muscle fiber type distribution and muscle metabolism, which ultimately protects against fat-induced obesity and improves aerobic exercise performance. PMID:26302153

  2. Biostable beta-amino acid PK/PBAN analogs: Agonist and antagonist properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pyrokinin/pheromone biosynthesis activating neuropeptide (PK/PBAN) family plays a significant role in a multifunctional array of important physiological processes in insects. PK/PBAN analogs incorporating beta-amino acids were synthesized and evaluated in a pheromonotropic assay in Heliothis pe...

  3. Insect Allergy.

    PubMed

    Lee, Hobart; Halverson, Sara; Mackey, Regina

    2016-09-01

    Insect bites and stings are common. Risk factors are mostly associated with environmental exposure. Most insect bites and stings result in mild, local, allergic reactions. Large local reactions and systemic reactions like anaphylaxis are possible. Common insects that bite or sting include mosquitoes, ticks, flies, fleas, biting midges, bees, and wasps. The diagnosis is made clinically. Identification of the insect should occur when possible. Management is usually supportive. For anaphylaxis, patients should be given epinephrine and transported to the emergency department for further evaluation. Venom immunotherapy (VIT) has several different protocols. VIT is highly effective in reducing systemic reactions and anaphylaxis. PMID:27545732

  4. Insect Keepers

    ERIC Educational Resources Information Center

    Moore, Virginia J.; Chessin, Debby A.; Theobald, Becky

    2010-01-01

    Insects are fascinating creatures--especially when you and your students get up close and personal with them! To that end, the authors facilitated an inquiry-based investigation with an emphasis on identification of the different types of insects found in the school yard, their characteristics, their habitat, and what they eat, while engaging the…

  5. Incredible Insects.

    ERIC Educational Resources Information Center

    Braus, Judy, Ed.

    1989-01-01

    Ranger Rick's NatureScope is a creative education series dedicated to inspiring in children an understanding and appreciation of the natural world while developing the skills they will need to make responsible decisions about the environment. Contents are organized into the following sections: (1) "What Makes an Insect an Insect?," including…

  6. Improvement of skin wound healing in diabetic mice by kinin B2 receptor blockade.

    PubMed

    Desposito, Dorinne; Chollet, Catherine; Taveau, Christopher; Descamps, Vincent; Alhenc-Gelas, François; Roussel, Ronan; Bouby, Nadine; Waeckel, Ludovic

    2016-01-01

    Impaired skin wound healing is a major medical problem in diabetic subjects. Kinins exert a number of vascular and other actions limiting organ damage in ischaemia or diabetes, but their role in skin injury is unknown. We investigated, through pharmacological manipulation of bradykinin B1 and B2 receptors (B1R and B2R respectively), the role of kinins in wound healing in non-diabetic and diabetic mice. Using two mouse models of diabetes (streptozotocin-induced and db/db mice) and non-diabetic mice, we assessed the effect of kinin receptor activation or inhibition by subtype-selective pharmacological agonists (B1R and B2R) and antagonist (B2R) on healing of experimental skin wounds. We also studied effects of agonists and antagonist on keratinocytes and fibroblasts in vitro. Levels of Bdkrb1 (encoding B1R) and Bdkrb2 (encoding B2R) mRNAs increased 1-2-fold in healthy and wounded diabetic skin compared with in non-diabetic skin. Diabetes delayed wound healing. The B1R agonist had no effect on wound healing. In contrast, the B2R agonist impaired wound repair in both non-diabetic and diabetic mice, inducing skin disorganization and epidermis thickening. In vitro, B2R activation unbalanced fibroblast/keratinocyte proliferation and increased keratinocyte migration. These effects were abolished by co-administration of B2R antagonist. Interestingly, in the two mouse models of diabetes, the B2R antagonist administered alone normalized wound healing. This effect was associated with the induction of Ccl2 (encoding monocyte chemoattractant protein 1)/Tnf (encoding tumour necrosis factor α) mRNAs. Thus stimulation of kinin B2 receptor impairs skin wound healing in mice. B2R activation occurs in the diabetic skin and delays wound healing. B2R blockade improves skin wound healing in diabetic mice and is a potential therapeutic approach to diabetic ulcers. PMID:26443866

  7. Renin-angiotensin-aldosterone-kinin system influences on diabetic vascular disease and cardiomyopathy.

    PubMed

    Flack, J M; Hamaty, M; Staffileno, B A

    1998-01-01

    Diabetes mellitus is associated with an inordinately high risk of virtually all manifestations of cardiovascular-renal disease including atherosclerotic coronary and peripheral vascular disease, congestive heart failure, stroke, nephropathy, and cardiomyopathy unassociated with coronary heart disease. Abnormalities in the renin-angiotensin-aldosterone-kinin (RAAK) cascade have been implicated in the pathogenesis and clinical expression of these cardiovascular-renal sequelae. Thus, pharmacological modulation of the RAAK system is an attractive therapeutic target in diabetes mellitus. Indeed, emerging data from human clinical studies appear to confirm this thesis. PMID:9930381

  8. Insect Phylogenomics

    PubMed Central

    Behura, Susanta K.

    2015-01-01

    With the advent of next-generation sequencing methods, phylogenetics has taken a new turn in the recent years. Phylogenomics, the integration of phylogenetics with genome data, has emerged as a powerful approach to study systematics and evolution of species. Recently, breakthrough researches employing phylogenomic tools have provided better insights into the timing and pattern of insect evolution. The next-generation sequencing methods are now increasingly used by entomologists to generate genomic and transcript sequences of various insect species and strains. These data provide opportunities for comparative genomics and large-scale multigene phylogenies of diverse lineages of insects. Phylogenomic investigations help us better understand systematic and evolutionary relationships of insect species that play important roles as herbivores, predators, detritivores, pollinators, or disease vectors. It is important that we critically assess the prospects and limitations of phylogenomic methods. In this review, I describe the current status, outline the major challenges, and remark on potential future applications of phylogenomic tools in studying insect systematics and evolution. PMID:25963452

  9. Effect of processing route and acetone pre-treatment on the biostability of pellethane materials used in medical device applications.

    PubMed

    Taylor, Jennifer Elizabeth; Laity, Peter R; Freeburn, Sharlene; Wong, Steven S; Norris, Keith; Khunkamchoo, Peck; Cable, Martin; Andrews, Geoffrey; Johnson, Anthony F; Cameron, Ruth E

    2005-11-01

    Thermoplastic polyurethanes, such as Pellethane 2363 80A (Pel80A) and Pellethane 2363 55D (Pel55D) are widely used in the medical device industry because of their biological and mechanical properties. However, premature failure in such devices has been observed and attributed to environmental stress cracking (ESC). The current work investigates the possibility of reducing ESC via bulk morphology manipulation. This can be achieved through various processing routes such as solvent-casting (SC) and hot-press quenching (HPQ). The effect of stress on the bulk morphology of Pel55D and Pel80A was evaluated using small-angle X-ray scattering (SAXS) in conjunction with tensile testing. SC samples exhibited greater phase separation compared with HPQ samples. Alignment of hard segment domains became apparent around the point of yield. Onset of ESC with respect to SC and HPQ routines was determined using the Zhao-Stokes glass-wool test with optical (OM) and environment scanning electron microscopy (ESEM). Improvement in biostability of Pel80A was found in HPQ samples compared to those that were SC. A secondary objective of this work was to investigate the effect of acetone pre-treatment on surface morphology. High resolution imaging of acetone treated and untreated SC Pel80A showed significant differences in surface morphology. PMID:15935471

  10. The Extreme Anterior Domain Is an Essential Craniofacial Organizer Acting through Kinin-Kallikrein Signaling

    PubMed Central

    Jacox, Laura; Sindelka, Radek; Chen, Justin; Rothman, Alyssa; Dickinson, Amanda; Sive, Hazel

    2014-01-01

    SUMMARY The extreme anterior domain (EAD) is a conserved embryonic region that includes the presumptive mouth. We show that the Kinin-Kallikrein pathway is active in the EAD and necessary for craniofacial development in Xenopus and zebrafish. The mouth failed to form and neural crest (NC) development and migration was abnormal after loss of function (LOF) in the pathway genes kng, encoding Bradykinin (xBdk), carboxypeptidase-N (cpn) that cleaves Bradykinin and neuronal nitric oxide synthase. Consistent with a role for nitric oxide (NO) in face formation, endogenous NO levels declined after LOF in pathway genes but these were restored and a normal face formed after medial implantation of xBdk-beads into LOF embryos. Facial transplants demonstrated that Cpn function from within the EAD is necessary for migration of first arch cranial NC into the face and to promote mouth opening. The study identifies the EAD as an essential craniofacial organizer acting through Kinin-Kallikrein signaling. PMID:25043181

  11. Captopril augments acetylcholine-induced bronchial smooth muscle contractions in vitro via kinin-dependent mechanisms.

    PubMed

    Agrawal, Naman; Akella, Aparna; Deshpande, Shripad B

    2016-06-01

    Angiotensin converting enzyme (ACE) inhibitors therapy is aassociated with bothersome dry cough as an adverse effect. The mechanisms underlying this adverse effect are not clear. Therefore, influence of captopril (an ACE inhibitor) on acetylcholine (ACh)-induced bronchial smooth muscle contractions was investigated. Further, the mechanisms underlying the captopril-induced changes were also explored. In vitro contractions of rat bronchial smooth muscle to cumulative concentrations of ACh were recorded before and after exposure to captopril. Further, the involvement of kinin and inositol triphosphate (IP₃) pathways for captopril-induced alterations were explored. ACh produced concentration-dependent (5-500 µM) increase in bronchial smooth muscle contractions. Pre-treatment with captopril augmented the ACh-induced contractions at each concentration significantly. Pre-treatment with aprotinin (kinin synthesis inhibitor) or heparin (inositol triphosphate, IP₃-inhibitor), blocked the captopril-induced augmentation of bronchial smooth muscle contractions evoked by ACh. Further, captopril-induced augmentation was absent in calcium-free medium. These results suggest that captopril sensitizes bronchial smooth muscles to ACh-induced contractions. This sensitization may be responsible for dry cough associated with captopril therapy. PMID:27468462

  12. Host kinin B1 receptor plays a protective role against melanoma progression

    PubMed Central

    Maria, Andrea G.; Dillenburg-Pilla, Patrícia; Reis, Rosana I.; Floriano, Elaine M.; Tefé-Silva, Cristiane; Ramos, Simone G.; Pesquero, João B.; Nahmias, Clara; Costa-Neto, Claudio M.

    2016-01-01

    Melanoma is a very aggressive tumor that arises from melanocytes. Late stage and widely spread diseases do not respond to standard therapeutic approaches. The kallikrein-kinin system (KKS) participates in biological processes such as vasodilatation, pain and inflammatory response. However, the role of KKS in tumor formation and progression is not completely understood. The role of the host kinin B1 receptor in melanoma development was evaluated using a syngeneic melanoma model. Primary tumors and metastasis were respectively induced by injecting B16F10 melanoma cells, which are derived from C57BL/6 mice, subcutaneously or in the tail vein in wild type C57BL/6 and B1 receptor knockout mice (B1−/−). Tumors developed in B1−/− mice presented unfavorable prognostic factors such as increased incidence of ulceration, higher levels of IL-10, higher activation of proliferative pathways such as ERK1/2 and Akt, and increased mitotic index. Furthermore, in the metastasis model, B1−/− mice developed larger metastatic colonies in the lung and lower CD8+immune effector cells when compared with WT animals. Altogether, our results provide evidences that B1−/− animals developed primary tumors with multiple features associated with poor prognosis and unfavorable metastatic onset, indicating that the B1 receptor may contribute to improve the host response against melanoma progression. PMID:26898917

  13. Diuretic and myotropic activities of N-terminal truncated analogs of Musca domestica kinin neuropeptide.

    PubMed

    Coast, Geoffrey M; Zabrocki, Janusz; Nachman, Ronald J

    2002-04-01

    Musca kinin (Musdo-K; NTVVLGKKQRFHSWG-NH(2)) and N-terminal truncated analogs of 4-14 residues in length were assayed for diuretic and myotropic activity on housefly Malpighian tubules and hindgut, respectively. The pentapeptide was the minimum sequence required for biological activity, but it was > 5 orders of magnitude less potent than the intact peptide. The pharmacological profiles of the different analogs in the two assays were very similar, suggesting the same receptor is present on both tissues. Potency was little affected by the deletion of Asn(1), but was reduced > 10-fold after the removal of Thr(2). Deletion of the next 5 residues had relatively little effect, but after the second lysyl residue (Lys(8)) was removed potency fell by one to two orders of magnitude. There was a similar drop in potency after the removal of Arg(10), and at 100 microM the pentapeptide had only 20% of the diuretic activity of the intact peptide. The importance of Arg(10) was confirmed by comparing dose-response curves for Musdo-K [6-15] and Acheta kinin-V (AFSHWG-NH(2)) in the diuretic assay; the substitution of arginine by alanine produced a significant reduction in potency and some loss of activity. PMID:11897389

  14. Nicotine enhances murine airway contractile responses to kinin receptor agonists via activation of JNK- and PDE4-related intracellular pathways

    PubMed Central

    2010-01-01

    Background Nicotine plays an important role in cigarette-smoke-associated airway disease. The present study was designed to examine if nicotine could induce airway hyperresponsiveness through kinin receptors, and if so, explore the underlying mechanisms involved. Methods Murine tracheal segments were cultured for 1, 2 or 4 days in serum-free DMEM medium in presence of nicotine (1 and 10 μM) or vehicle (DMSO). Contractile responses induced by kinin B1 receptor agonist, des-Arg9-bradykinin, and B2 receptor agonist, bradykinin, were monitored with myographs. The B1 and B2 receptor mRNA expressions were semi-quantified using real-time PCR and their corresponding protein expressions assessed with confocal-microscopy-based immunohistochemistry. Various pharmacological inhibitors were used for studying intracellular signaling pathways. Results Four days of organ culture with nicotine concentration-dependently increased kinin B1 and B2 receptor-mediated airway contractions, without altering the kinin receptor-mediated relaxations. No such increase was seen at day 1 or day 2. The airway contractile responses to 5-HT, acetylcholine and endothelin receptor agonists remained unaffected by nicotine. Two different neuronal nicotinic receptor antagonists MG624 and hexamethonium blocked the nicotine-induced effects. The enhanced contractile responses were accompanied by increased mRNA and protein expression for both kinin receptors, suggesting the involvement of transcriptional mechanisms. Confocal-microscopy-based immunohistochemistry showed that 4 days of nicotine treatment induced activation (phosphorylation) of c-Jun N-terminal kinase (JNK), but not extracellular signal-regulated kinase 1 and 2 (ERK1/2) and p38. Inhibition of JNK with its specific inhibitor SP600125 abolished the nicotine-induced effects on kinin receptor-mediated contractions and reverted the enhanced receptor mRNA expression. Administration of phosphodiesterase inhibitors (YM976 and theophylline

  15. Differential regulation of collagen secretion by kinin receptors in cardiac fibroblast and myofibroblast

    SciTech Connect

    Catalán, Mabel; Smolic, Christian; Contreras, Ariel; Ayala, Pedro; Olmedo, Ivonne; Copaja, Miguel; Boza, Pía; Vivar, Raúl; Avalos, Yennifer; Lavandero, Sergio; Velarde, Victoria; Díaz-Araya, Guillermo

    2012-06-15

    Kinins mediate their cellular effects through B1 (B1R) and B2 (B2R) receptors, and the activation of B2R reduces collagen synthesis in cardiac fibroblasts (CF). However, the question of whether B1R and/or B2R have a role in cardiac myofibroblasts remains unanswered. Methods: CF were isolated from neonate rats and myofibroblasts were generated by an 84 h treatment with TGF-β1 (CMF). B1R was evaluated by western blot, immunocytochemistry and radioligand assay; B2R, inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS), and cyclooxygenases 1and 2 (COX-1, and COX-2) were evaluated by western blot; intracellular Ca{sup +2} levels were evaluated with Fluo-4AM; collagen secretion was measured in the culture media using the picrosirius red assay kit. Results: B2R, iNOS, COX-1 and low levels of B1R but not eNOS, were detected by western blot in CF. Also, B1R, B2R, and COX-2 but not iNOS, eNOS or COX-1, were detected by western blot in CMF. By immunocytochemistry, our results showed lower intracellular B1R levels in CF and higher B1R levels in CMF, mainly localized on the cell membrane. Additionally, we found B1R only in CMF cellular membrane through radioligand displacement assay. Bradykinin (BK) B2R agonist increased intracellular Ca{sup 2+} levels and reduced collagen secretion both in CF and CMF. These effects were blocked by HOE-140, and inhibited by L-NAME, 1400W and indomethacin. Des-Arg-kallidin (DAKD) B1R agonist did not increase intracellular Ca{sup 2+} levels in CF; however, after preincubation for 1 h with DAKD and re-stimulation with the same agonist, we found a low increase in intracellular Ca{sup 2+} levels. Finally, DAKD increased intracellular Ca{sup 2+} levels and decreased collagen secretion in CMF, being this effect blocked by the B1R antagonist des-Arg9-Leu8-kallidin and indomethacin, but not by L-NAME or 1400 W. Conclusion: B1R, B2R, iNOS and COX-1 were expressed differently between CF and CMF, and collagen secretion was

  16. Endogenous bradykinin activates ischaemically sensitive cardiac visceral afferents through kinin B2 receptors in cats

    PubMed Central

    Tjen-A-Looi, Stephanie C; Pan, Hui-Lin; Longhurst, John C

    1998-01-01

    Activity of ischaemically sensitive cardiac visceral afferents during myocardial ischaemia induces both angina and cardiovascular reflexes. Increased production of bradykinin (BK) and cyclo-oxygenase products (i.e. prostaglandins (PGs)) occurs during myocardial ischaemia. However, the role of these agents in activation of ischaemically sensitive cardiac afferents has not been established. The present study tested the hypothesis that BK produced during ischaemia activates cardiac afferents through kinin B2 receptors. Single-unit activity of cardiac afferents innervating the left ventricle was recorded from the left thoracic sympathetic chain (T1–T4) of anaesthetized cats. Ischaemically sensitive cardiac afferents were identified according to their response to 5 min of myocardial ischaemia. The mechanism of BK in activation of ischaemically sensitive cardiac afferents was determined by injection of BK (1 μg kg−1 i.a.), des-Arg9-BK (1 μg kg−1 i.a., a specific kinin B1 receptor agonist), kinin B2 receptor antagonists: HOE140 (30 μg kg−1 i.v.) and NPC-17731 (40 μg kg−1 i.v.), cyclo-oxygenase inhibition with indomethacin (5 mg kg−1 i.v.) and NPC-17731 (40 μg kg−1 i.v.) after pretreatment with indomethacin (5 mg kg−1 i.v.). We observed that BK increased the discharge rate of all eleven ischaemically sensitive cardiac afferents from 0.39 ± 0.12 to 1.47 ± 0.37 impulses s−1 (P < 0.05). Conversely, des-Arg9-BK did not significantly increase the activity of eleven ischaemically sensitive fibres (0.58 ± 0.02 vs. 0.50 ± 0.18 impulses s−1). HOE140 significantly attenuated the response of twelve afferents to ischaemia (0.61 ± 0.22 to 1.85 ± 0.5 vs. 0.53 ± 0.16 to 1.09 ± 0.4 impulses s−1). NPC-17731, another kinin B2 receptor antagonist, had similar inhibitory effects on six other ischaemically sensitive cardiac afferents (0.35 ± 0.14 to 1.19 ± 0.29 vs. 0.22 ± 0.08 to 0.23 ± 0.07 impulses s−1). Indomethacin significantly reduced the

  17. Insects: A nutritional alternative

    NASA Technical Reports Server (NTRS)

    Dufour, P. A.

    1981-01-01

    Insects are considered as potential food sources in space. Types of insects consumed are discussed. Hazards of insect ingestion are considered. Insect reproduction, requirements, and raw materials conversion are discussed. Nutrition properties and composition of insects are considered. Preparation of insects as human food is discussed.

  18. Insect evolution.

    PubMed

    Engel, Michael S

    2015-10-01

    It goes without saying that insects epitomize diversity, and with over a million documented species they stand out as one of the most remarkable lineages in the 3.5-billion-year history of life on earth (Figure 1). This reality is passé to even the layperson and is taken for granted in the same way none of us think much of our breathing as we go about our day, and yet insects are just as vital to our existence. Insects are simultaneously familiar and foreign to us, and while a small fraction are beloved or reviled, most are simply ignored. These inexorable evolutionary overachievers outnumber us all, their segmented body plan is remarkably labile, they combine a capacity for high rates of speciation with low levels of natural extinction, and their history of successes eclipses those of the more familiar ages of dinosaurs and mammals alike. It is their evolution - persisting over vast expanses of geological time and inextricably implicated in the diversification of other lineages - that stands as one of the most expansive subjects in biology. PMID:26439349

  19. Kinin B1 Receptor Deletion Affects Bone Healing in Type 1 Diabetic Mice.

    PubMed

    Cignachi, Natália P; Pesquero, João B; Oliveira, Rogério B; Etges, Adriana; Campos, Maria M

    2015-12-01

    The effects of kinin B1 receptor (B1 R) deletion were examined on femur bone regeneration in streptozotocin (STZ)-type 1 diabetes. Diabetes induction in wild-type C57/BL6 (WTC57BL6) mice led to decrease in body weight and hyperglycemia, compared to the non-diabetic group of the same strain. The lack of B1 R did not affect STZ-elicited body weight loss, but partially prevented hyperglycemia. Diabetic mice had a clear delay in bone regeneration, and displayed large areas of loose connective tissue within the defects, with a reduced expression of the mineralization-related protein osteonectin, when compared to the non-diabetic WTC57/BL6. The non-diabetic and diabetic B1 R knockout (B1 RKO) mice had bone regeneration levels and osteonectin expression comparable to that seen in control WTC57/BL6 mice. WTC57/BL6 STZ-diabetic mice also showed a marked reduction of collagen contents, with increased immunolabeling for the apoptosis marker caspase-3, whereas diabetic B1 RKO had collagen levels and caspase-3 activity comparable to those observed in non-diabetic WTC57/BL6 or B1 RKO mice. No significant difference was detected in the number of tartrate-resistant acid phosphatase (TRAP)-stained cells, or in RANK/RANKL/OPG system immunolabeling throughout the experimental groups. Data bring novel evidence on the relevance of kinin B1 R under type 1 diabetes with regards to its role in bone regeneration. PMID:25969420

  20. Insect abatement system

    NASA Technical Reports Server (NTRS)

    Spiro, Clifford Lawrence (Inventor); Burnell, Timothy Brydon (Inventor); Wengrovius, Jeffrey Hayward (Inventor)

    1997-01-01

    An insect abatement system prevents adhesion of insect debris to surfaces which must be kept substantially free of insect debris. An article is coated with an insect abatement coating comprising polyorganosiloxane with a Shore A hardness of less than 50 and a tensile strength of less than 4 MPa. A method for preventing the adhesion of insect debris to surfaces includes the step of applying an insect abatement coating to a surface which must be kept substantially free of insect debris.

  1. Rational design of novel N-alkyl-N capped biostable RNA nanostructures for efficient long-term inhibition of gene expression.

    PubMed

    Terrazas, Montserrat; Ivani, Ivan; Villegas, Núria; Paris, Clément; Salvans, Cándida; Brun-Heath, Isabelle; Orozco, Modesto

    2016-05-19

    Computational techniques have been used to design a novel class of RNA architecture with expected improved resistance to nuclease degradation, while showing interference RNA activity. The in silico designed structure consists of a 24-29 bp duplex RNA region linked on both ends by N-alkyl-N dimeric nucleotides (BCn dimers; n = number of carbon atoms of the alkyl chain). A series of N-alkyl-N capped dumbbell-shaped structures were efficiently synthesized by double ligation of BCn-loop hairpins. The resulting BCn-loop dumbbells displayed experimentally higher biostability than their 3'-N-alkyl-N linear version, and were active against a range of mRNA targets. We studied first the effect of the alkyl chain and stem lengths on RNAi activity in a screen involving two series of dumbbell analogues targeting Renilla and Firefly luciferase genes. The best dumbbell design (containing BC6 loops and 29 bp) was successfully used to silence GRB7 expression in HER2+ breast cancer cells for longer periods of time than natural siRNAs and known biostable dumbbells. This BC6-loop dumbbell-shaped structure displayed greater anti-proliferative activity than natural siRNAs. PMID:26975656

  2. Rational design of novel N-alkyl-N capped biostable RNA nanostructures for efficient long-term inhibition of gene expression

    PubMed Central

    Terrazas, Montserrat; Ivani, Ivan; Villegas, Núria; Paris, Clément; Salvans, Cándida; Brun-Heath, Isabelle; Orozco, Modesto

    2016-01-01

    Computational techniques have been used to design a novel class of RNA architecture with expected improved resistance to nuclease degradation, while showing interference RNA activity. The in silico designed structure consists of a 24–29 bp duplex RNA region linked on both ends by N-alkyl-N dimeric nucleotides (BCn dimers; n = number of carbon atoms of the alkyl chain). A series of N-alkyl-N capped dumbbell-shaped structures were efficiently synthesized by double ligation of BCn-loop hairpins. The resulting BCn-loop dumbbells displayed experimentally higher biostability than their 3′-N-alkyl-N linear version, and were active against a range of mRNA targets. We studied first the effect of the alkyl chain and stem lengths on RNAi activity in a screen involving two series of dumbbell analogues targeting Renilla and Firefly luciferase genes. The best dumbbell design (containing BC6 loops and 29 bp) was successfully used to silence GRB7 expression in HER2+ breast cancer cells for longer periods of time than natural siRNAs and known biostable dumbbells. This BC6-loop dumbbell-shaped structure displayed greater anti-proliferative activity than natural siRNAs. PMID:26975656

  3. Inhibition of kinin breakdown prolongs retention and action of bradykinin in a myocardial B2 receptor compartment

    PubMed Central

    Dendorfer, Andreas; Folkers, Verena; Klinger, Matthias; Wolfrum, Sebastian; Dominiak, Peter

    2003-01-01

    The high efficacy of ACE inhibitors to potentiate the actions of kinins might be explained by a hypothetical compartment in which B2-receptors are colocalized with kinin degrading enzymes. To demonstrate the functional consequence of such a compartment we compared the myocardial uptake and the persistence of action of bradykinin under the influence of kininase inhibitors. Bradykinin-induced vasodilation and uptake of tritiated bradykinin were studied in perfused rat hearts during inhibition of ACE and aminopeptidase P. B2-receptors were localized by immuno-gold labelling and electron-microscopy. The EC50 of bradykinin-induced vasodilation (5.1±0.8 nM) was shifted to 14 fold lower concentrations during inhibition of both kininases. The maximum persistence of vasodilation after termination of bradykinin application (half-life 112±20 s) was increased by kininase inhibitors to 398±130 s. This prolongation was reversed when B2-receptors were blocked simultaneously with the termination of bradykinin infusion. Tritiated bradykinin (perfused for 1 min) was partially (1.7±0.24%) retained by the myocardium and consecutively released with a half-life of 70±9 s. Kinin uptake was increased during kininase inhibition (7.7±2.6%), and was normalized by HOE 140 (2.0±0.34%), or when a tritiated B2-receptor antagonist (NPC 17731) was used as label. B2-receptors were localized in plasmalemmal and cytosolic vesicles of capillary endothelium. Bradykinin is locally incorporated and can associate with B2-receptors repeatedly when kinin breakdown is inhibited. This is the kinetic and functional consequence of a colocalization of kininases and B2-receptors in a compartment constituted by endothelial membrane vesicles. PMID:12540521

  4. Allergies to Insect Venom

    MedlinePlus

    ... The smell of food attracts these insects.  Use insect repellents and keep insecticide available. Treatment tips:  Venom immunotherapy (allergy shots to insect venom(s) is highly effective in preventing subsequent sting ...

  5. Effects of the Demethylating Agent, 5-Azacytidine, on Expression of the Kallikrein-Kinin Genes in Carcinoma Cells of the Lung and Pleura

    PubMed Central

    Wong, Joshua; Sia, Yee Yen; Misso, Neil L.; Aggarwal, Shashi; Ng, Angeline; Bhoola, Kanti D.

    2011-01-01

    Tissue kallikrein (KLK1) and plasma kallikrein (KLKB1) may regulate the growth and proliferation of tumours of the lung and pleura, through the generation of kinin peptides that signal through the kinin B1 (BDKRB1) and B2 (BDKRB2) receptors. The development and progression of cancer results from genetic mutations, as well as epigenetic changes that include methylation of DNA at CpG islands. The aim of this study was to assess whether expression of the kallikrein-kinin genes in lung cancer and mesothelioma cells is regulated by DNA methylation. Quantitative reverse transcriptase-PCR and immunocytochemistry showed differences in the basal expression of the kallikrein-kinin genes and proteins in lung carcinoma and mesothelioma cells, compared with non-malignant lung epithelial and mesothelial cells, respectively. Following treatment with the demethylating agent, 5-azacytidine (5-AZA), KLKB1 mRNA expression was consistently increased in both lung carcinoma and mesothelioma cells, whereas KLK1, BDKRB1 and BDKRB2 mRNA expression was decreased or unchanged. Increased expression of KLKB1 after 5-AZA treatment suggests it may function as a tumour suppressor gene in cancers of the lung and pleura. Studies on DNA methylation of the kallikrein-kinin genes will enhance understanding of their role in carcinogenesis and provide insights into the importance of kallikreins as tumour biomarkers. PMID:21904690

  6. Release of biologically active kinin peptides, Met-Lys-bradykinin and Leu-Met-Lys-bradykinin from human kininogens by two major secreted aspartic proteases of Candida parapsilosis.

    PubMed

    Bras, Grazyna; Bochenska, Oliwia; Rapala-Kozik, Maria; Guevara-Lora, Ibeth; Faussner, Alexander; Kamysz, Wojciech; Kozik, Andrzej

    2013-10-01

    In terms of infection incidence, the yeast Candida parapsilosis is the second after Candida albicans as causative agent of candidiases in humans. The major virulence factors of C. parapsilosis are secreted aspartic proteases (SAPPs) which help the pathogen to disseminate, acquire nutrients and dysregulate the mechanisms of innate immunity of the host. In the current work we characterized the action of two major extracellular proteases of C. parapsilosis, SAPP1 and SAPP2, on human kininogens, proteinaceous precursors of vasoactive and proinflammatory bradykinin-related peptides, collectively called the kinins. The kininogens, preferably the form with lower molecular mass, were effectively cleaved by SAPPs, with the release of two uncommon kinins, Met-Lys-bradykinin and Leu-Met-Lys-bradykinin. While optimal at acidic pH (4-5), the kinin release yield was only 2-3-fold lower at neutral pH. These peptides were able to interact with cellular kinin receptors of B2 subtype and to stimulate the human endothelial cells HMEC-1 to increased secretion of proinflammatory interleukins (ILs), IL-1β and IL-6. The analysis of the stability of SAPP-generated kinins in plasma suggested that they are biologically equivalent to bradykinin, the best agonist of B2 receptor subtype and can be quickly converted to des-Arg(9)-bradykinin, the agonist of inflammation-inducible B1 receptors. PMID:23954712

  7. Insect transgenesis and the sterile insect technique

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The establishment of broadly applicable insect transgenesis systems will enable the analyses of gene function in diverse insect species. This will greatly increase our understanding of diverse aspects of biology so far not functionally addressable. Moreover, insect transgenesis will provide novel st...

  8. What Makes an Insect an Insect?

    ERIC Educational Resources Information Center

    NatureScope, 1985

    1985-01-01

    Provides background information on characteristics common to all insects, activities, and student materials (ready-to-copy games, puzzles, coloring pages, worksheets, and/or mazes) which describe: how insects are classified; how they are different from other animals; and the main insect characteristics. Activities include recommended age levels,…

  9. Downregulation of kinin B1 receptor function by B2 receptor heterodimerization and signaling

    PubMed Central

    Zhang, Xianming; Brovkovych, Viktor; Zhang, Yongkang; Tan, Fulong; Skidgel, Randal A.

    2014-01-01

    Signaling through the G protein-coupled kinin receptors B1 (kB1R) and B2 (kB2R) plays a critical role in inflammatory responses mediated by activation of the kallikrein-kinin system. The kB2R is constitutively expressed and rapidly desensitized in response to agonist whereas kB1R expression is upregulated by inflammatory stimuli and it is resistant to internalization and desensitization. Here we show that the kB1R heterodimerizes with kB2Rs in co-transfected HEK293 cells and natively expressing endothelial cells, resulting in significant internalization and desensitization of the kB1R response in cells pre-treated with kB2R agonist. However, pre-treatment of cells with kB1R agonist did not affect subsequent kB2R responses. Agonists of other G protein-coupled receptors (thrombin, lysophosphatidic acid) had no effect on a subsequent kB1R response. The loss of kB1R response after pretreatment with kB2R agonist was partially reversed with kB2R mutant Y129S, which blocks kB2R signaling without affecting endocytosis, or T342A, which signals like wild type but is not endocytosed. Co-endocytosis of the kB1R with kB2R was dependent on β-arrestin and clathrin-coated pits but not caveolae. The sorting pathway of kB1R and kB2R after endocytosis differed as recycling of kB1R to the cell surface was much slower than that of kB2R. In cytokine-treated human lung microvascular endothelial cells, pre-treatment with kB2R agonist inhibited kB1R-mediated increase in transendothelial electrical resistance (TER) caused by kB1R stimulation (to generate nitric oxide) and blocked the profound drop in TER caused by kB1R activation in the presence of pyrogallol (a superoxide generator). Thus, kB1R function can be downregulated by kB2R co-endocytosis and signaling, suggesting new approaches to control kB1R signaling in pathological conditions. PMID:25289859

  10. The Role of the Kallikrein-Kinin System Genes in the Salt Sensitivity of Blood Pressure

    PubMed Central

    Gu, Dongfeng; Zhao, Qi; Kelly, Tanika N.; Hixson, James E.; Rao, Dabeeru C.; Cao, Jie; Chen, Jing; Li, Jianxin; Chen, Jichun; Ji, Xu; Hu, Dongsheng; Wang, Xushan; Liu, De-Pei; He, Jiang

    2012-01-01

    The current study comprehensively examined the association between common genetic variants of the kallikrein-kinin system (KKS) and blood pressure salt sensitivity. A 7-day low-sodium followed by a 7-day high-sodium dietary intervention was conducted among 1,906 Han Chinese participants recruited from 2003 to 2005. Blood pressure was measured by using a random-zero sphygmomanometer through the study. A total of 205 single nucleotide polymorphisms (SNPs) covering 11 genes of the KKS were selected for the analyses. Genetic variants of the bradykinin receptor B2 gene (BDKRB2) and the endothelin converting enzyme 1 gene (ECE1) showed significant associations with the salt-sensitivity phenotypes even after adjustment for multiple testing. Compared with the major G allele, the BDKRB2 rs11847625 minor C allele was significantly associated with increased systolic blood pressure responses to low-sodium intervention (P = 0.0001). Furthermore, a haplotype containing allele C was associated with an increased systolic blood pressure response to high-sodium intervention (P = 0.0009). Seven highly correlated ECE1 SNPs were shown to increase the diastolic blood pressure response to low-sodium intervention (P values ranged from 0.0003 to 0.002), with 2 haplotypes containing these 7 SNPs also associated with this same phenotype (P values ranged from 0.0004 to 0.002). In summary, genetic variants of the genes involved in the regulation of KKS may contribute to the salt sensitivity of blood pressure. PMID:23035147

  11. Inhibition by CāINH of Hageman Factor Fragment Activation of Coagulation, Fibrinolysis, and Kinin Generation

    PubMed Central

    Schreiber, Alan D.; Kaplan, Allen P.; Austen, K. Frank

    1973-01-01

    Highly purified inhibitor of the first component of complement (CāINH) was shown to inhibit the capacity of active Hageman factor fragments to initiate kinin generation, fibrinolysis, and coagulation. The inhibition of prealbumin Hageman factor fragments observed was dependent upon the time of interaction of the fragments with CāINH and not to an effect upon kallikrein or plasmin generated. The inhibition of the coagulant activity of the intermediate sized Hageman factor fragment by CāINH was not due to an effect on PTA or other clotting factors. The inhibition by CāINH of both the prealbumin and intermediate sized Hageman factor fragments occurred in a dose response fashion. The CāINH did not appear to be consumed when the activity of the Hageman factor fragments was blocked, although the fragments themselves could no longer be recovered functionally or as a protein on alkaline disc gel electrophoretic analysis. These results suggest that the CāINH may have an enzymatic effect on the fragments or that an additional site on CāINH is involved in Cā inactivation. Images PMID:4703226

  12. The contact activation and kallikrein/kinin systems: pathophysiologic and physiologic activities.

    PubMed

    Schmaier, A H

    2016-01-01

    The contact activation system (CAS) and kallikrein/kinin system (KKS) are older recognized biochemical pathways that include several proteins that skirt the fringes of the blood coagulation, fibrinolytic, complement and renin-angiotensin fields. These proteins initially were proposed as part of the hemostatic pathways because their deficiencies are associated with prolonged clinical assays. However, the absence of bleeding states with deficiencies of factor XII (FXII), prekallikrein (PK) and high-molecular-weight kininogen indicates that the CAS and KKS do not contribute to hemostasis. Since the discovery of the Hageman factor 60 years ago much has been learned about the biochemistry, cell biology and animal physiology of these proteins. The CAS is a pathophysiologic surface defense mechanism against foreign proteins, organisms and artificial materials. The KKS is an inflammatory response mechanism. Targeting their activation through FXIIa or plasma kallikrein inhibition when blood interacts with the artificial surfaces of modern interventional medicine or in acute attacks of hereditary angioedema restores vascular homeostasis. FXII/FXIIa and products that arise with PK deficiency also offer novel ways to reduce arterial and venous thrombosis without an effect on hemostasis. In summary, there is revived interest in the CAS and KKS due to better understanding of their activities. The new appreciation of these systems will lead to several new therapies for a variety of medical disorders. PMID:26565070

  13. Interaction of Bacteroides fragilis and Bacteroides thetaiotaomicron with the kallikrein–kinin system

    PubMed Central

    Mörgelin, Matthias; Cooney, Jakki C.; Frick, Inga-Maria

    2011-01-01

    Many bacterial pathogens interfere with the contact system (kallikrein–kinin system) in human plasma. Activation of this system has two consequences: cleavage of high-molecular-mass kininogen (HK) resulting in release of the potent proinflammatory peptide bradykinin, and initiation of the intrinsic pathway of coagulation. In this study, two species of the Gram-negative anaerobic commensal organism Bacteroides, namely Bacteroides fragilis and Bacteroides thetaiotaomicron, were found to bind HK and fibrinogen, the major clotting protein, from human plasma as shown by immunoelectron microscopy and Western blot analysis. In addition, these Bacteroides species were capable of activating the contact system at its surface leading to a significant prolongation of the intrinsic coagulation time and also to the release of bradykinin. Members of the genus Bacteroides have been known to act as opportunistic pathogens outside the gut, with B. fragilis being the most common isolate from clinical infections, such as intra-abdominal abscesses and bacteraemia. The present results thus provide more insight into how Bacteroides species cause infection. PMID:21527472

  14. T-kininogen inhibits kinin-mediated activation of ERK in endothelial cells.

    PubMed

    Leiva-Salcedo, Elias; Perez, Viviana; Acuña-Castillo, Claudio; Walter, Robin; Sierra, Felipe

    2002-01-01

    Serum levels of T-kininogen increase dramatically as rats approach the end of their lifespan. Stable expression of the protein in Balb/c 3T3 fibroblasts leads to a dramatic inhibition of cell proliferation, as well as inhibition of the ERK signaling pathway. T-kininogen is a potent inhibitor of cysteine proteinases, and we have described that the inhibition of ERK activity occurs, at least in part, via stabilization of the MAP kinase phosphatase, MKP-1. Since fibroblasts are not a physiological target of T-kininogen, we have now purified the protein from rat serum, and used it to assess the effect of T-kininogen on endothelial cells. Adding purified T-kininogen to EAhy 926 hybridoma cells resulted in inhibition of basal ERK activity levels, as estimated using appropriate anti-phospho ERK antibodies. Furthermore, exogenously added T-kininogen inhibited the activation of the ERK pathway induced by either bradykinin or T-kinin. We conclude that the age-related increase in hepatic T-kininogen gene expression and serum levels of the protein could have dramatic consequences on endothelial cell physiology, both under steady state conditions, and after activation by cell-specific stimuli. Our results are consistent with T-kininogen being an important modulator of the senescent phenotype in vivo. PMID:12415746

  15. Book Review: Insect Virology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viruses that infect insects have long been of interest both as a means for controlling insect pest populations in an environmentally safe manner, and also as significant threats to beneficial insects of great value, such as honey bees and silkworms. Insect viruses also have been of intrinsic intere...

  16. Insect-ual Pursuits.

    ERIC Educational Resources Information Center

    Mallow, David

    1991-01-01

    Explains how insects can be used to stimulate student writing. Describes how students can create their own systems to classify and differentiate insects. Discusses insect morphology and includes three detailed diagrams. The author provides an extension activity where students hypothesize about the niche of an insect based on its anatomy. (PR)

  17. Inflammatory muscle pain is dependent on the activation of kinin B1 and B2 receptors and intracellular kinase pathways

    PubMed Central

    Meotti, FC; Campos, R; da Silva, KABS; Paszcuk, AF; Costa, R; Calixto, JB

    2012-01-01

    BACKGROUND AND PURPOSE B1 and B2 kinin receptors are involved in pain transmission but they may have different roles in the muscle pain induced by intense exercise or inflammation. We investigated the contribution of each of these receptors, and the intracellular pathways involved, in the initial development and maintenance of the muscle pain associated with inflammation-induced tissue damage. EXPERIMENTAL APPROACH Mechanical hyperalgesia was measured using the Randall–Selitto apparatus after injecting 5% formalin solution into the gastrocnemius muscle in mice treated with selective antagonists for B1 or B2 receptors. The expression of kinin receptors and cytokines and the activation of intracellular kinases were monitored by real-time PCR and immunohistochemistry. KEY RESULTS The i.m. injection of formalin induced an overexpression of B1 and B2 receptors. This overexpression was associated with the mechanical hyperalgesia induced by formalin because treatment with B1 receptor antagonists (des-Arg9[Leu8]-BK, DALBK, and SSR240612) or B2 receptor antagonists (HOE 140 and FR173657) prevented the hyperalgesia. Formalin increased myeloperoxidase activity, and up-regulated TNF-α, IL-1β and IL-6 in gastrocnemius. Myeloperoxidase activity and TNF-α mRNA expression were inhibited by either DALBK or HOE 140, whereas IL-6 was inhibited only by HOE 140. The hyperalgesia induced by i.m. formalin was dependent on the activation of intracellular MAPKs p38, JNK and PKC. CONCLUSIONS AND IMPLICATIONS Inflammatory muscle pain involves a cascade of events that is dependent on the activation of PKC, p38 and JNK, and the synthesis of IL-1β, TNF-α and IL-6 associated with the up-regulation of both B1 and B2 kinin receptors. PMID:22220695

  18. Differential regulation of inducible and endothelial nitric oxide synthase by kinin B1 and B2 receptors

    PubMed Central

    Kuhr, F.; Lowry, J.; Zhang, Y.; Brovkovych, V.; Skidgel, R.A.

    2010-01-01

    Kinins are vasoactive peptides that play important roles in cardiovascular homeostasis, pain and inflammation. After release from their precursor kininogens, kinins or their C-terminal des-Arg metabolites activate two distinct G protein-coupled receptors (GPCR), called B2 (B2R) or B1 (B1R). The B2R is expressed constitutively with a wide tissue distribution. In contrast, the B1R is not expressed under normal conditions but is upregulated by tissue insult or inflammatory mediators. The B2R is considered to mediate many of the acute effects of kinins while the B1R is more responsible for chronic responses in inflammation. Both receptors can couple to Gαi and Gαq families of G proteins to release mediators such as nitric oxide (NO), arachidonic acid, prostaglandins, leukotrienes and endothelium derived hyperpolarizing factor and can induce the release of other inflammatory agents. The focus of this review is on the different transduction events that take place upon B2R and B1R activation in human endothelial cells that leads to generation of NO via activation of different NOS isoforms. Importantly, B2R-mediated eNOS activation leads to a transient (~ 5 min) output of NO in control endothelial cells whereas in cytokine-treated endothelial cells, B1R activation leads to very high and prolonged (~90 min) NO production that is mediated by a novel signal transduction pathway leading to post-translational activation of iNOS. PMID:20045558

  19. Plasma Kallikrein-Kinin system mediates immune-mediated renal injury in trichloroethylene-sensitized mice.

    PubMed

    Wang, Hui; Zhang, Jia-Xiang; Ye, Liang-Ping; Li, Shu-Long; Wang, Feng; Zha, Wan-Sheng; Shen, Tong; Wu, Changhao; Zhu, Qi-Xing

    2016-07-01

    Trichloroethylene (TCE) is a major environmental pollutant. An immunological response is a newly-recognized mechanism for TCE-induced kidney damage. However, the role of the plasma kallikrein-kinin system (KKS) in immune-mediated kidney injury has never been examined. This study aimed to explore the role of the key components of the KKS, i.e. plasma kallikrein (PK), bradykinin (BK) and its receptors B1R and B2R, in TCE-induced kidney injury. A mouse model of skin sensitization was used to explore the mechanism of injury with or without a PK inhibitor PKSI. Kidney function was evaluated by measuring blood urea nitrogen (BUN) and creatinine (Cr) in conjunction with histopathologic characterization. Plasma BK was determined by ELISA; Renal C5b-9 membrane attack complex was evaluated by immunohistochemistry. Expression of BK and PK in the kidney was detected by immunofluorescence. mRNA and protein levels of B1R and B2R were assessed by real-time qPCR and Western blot. As expected, numerous inflammatory cell infiltration and tubular epithelial cell vacuolar degeneration were observed in TCE-sensitized mice. Moreover, serum BUN and Cr and plasma BK were increased. In addition, deposition of BK, PK and C5b-9 were observed and B1R and B2R mRNA and proteins levels were up-regulated. Pre-treatment with PKSI, a highly selective inhibitor of PK, alleviated TCE-induced renal damage. In addition, PKSI attenuated TCE-induced up-regulation of BK, PK and its receptors and C5b-9. These results provided the first evidence that activation of the KKS contributed to immune-mediated renal injury induced by TCE and also helped to identify the KKS as a potential therapeutic target for mitigating chemical sensitization-induced renal damage. PMID:27027470

  20. Kallikrein kinin system activation in post-exercise hypotension in water running of hypertensive volunteers.

    PubMed

    Pontes, Francisco L; Bacurau, Reury F P; Moraes, Milton R; Navarro, Francisco; Casarini, Dulce E; Pesquero, Jorge L; Pesquero, João B; Araújo, Ronaldo C; Piçarro, Ivan C

    2008-02-01

    Previous studies demonstrated a reduction in blood pressure level immediately after different types of exercises, like running, cycling and resistance training, a phenomenon called post-exercise hypotension (PEH). Since PEH can persist for hours it could be suggested as a non-pharmacological therapy for hypertensive individuals. Unfortunately, usually running is not recommended due to the high impact caused by its practice. Therefore running in water treadmill should be a better option, since the environment is completely different and causes lower impact. However it is not known whether PEH occurs in this situation. The objective of this work was to evaluate the existence of PEH after water running and to compare PEH promoted by running in two different environments. In addition, changes in plasmatic concentrations of the kallikrein kinin system (KKS) components were also evaluated. Sixteen hypertensive subjects were submitted to two exercise sessions, conventional running and water running, in two different occasions. The pattern of heart rate, blood pressure and plasmatic concentrations of KKS components immediately after and one hour after exercise were investigated. Results showed a maximal reduction in systolic and diastolic blood pressure 30 min after both exercise models (P<0.001), indicating that moderate water running promotes PEH with similar magnitude as compared to conventional running. Plasma kallikrein activity and bradykinin concentration increased immediately after exercise (P<0.05), but these parameters were not different in both exercise models. In conclusion, our findings show that water running, similarly to conventional running, can also provoke PEH and alterations in the KKS components. PMID:18182237

  1. Kinin B1 receptor homo-oligomerization is required for receptor trafficking to the cell surface.

    PubMed

    Sandén, Caroline; Leeb-Lundberg, L M Fredrik

    2013-01-01

    The kinin B1 receptor (B1R) is a G protein-coupled receptor with pro-inflammatory activity that is latent in healthy tissues but induced by tissue insult. Here, we investigated if B1R homo-oligomerization is a possible mechanism regulating the presentation of this receptor at the level of maturation and trafficking to the cell surface. To this end, we used HEK293 cells stably expressing N-terminal FLAG and HA epitope-tagged wild-type human B1R and an N-terminal receptor fragment, B1stop135, which terminates at the C-terminal end of the third transmembrane domain and has previously been shown to oligomerize with B1R. Receptors were monitored by immunoblotting and immunoprecipitation, receptor function by agonist binding and agonist-promoted phosphoinositide hydrolysis, and receptor trafficking by confocal immunofluorescence microscopy. When expressed alone, B1R is core N-glycosylated and forms oligomers localized intracellularly and on the cell surface. B1stop135 also exists as core N-glycosylated oligomers but is localized exclusively intracellularly. When co-expressed, B1stop135 prevents specifically B1R homo-oligomerization by forming nonfunctional B1R-B1stop135 hetero-oligomers, retains B1R intracellularly at least in part in the endoplasmatic reticulum (ER), increases calnexin binding to the receptor, and increases receptor degradation. We conclude that B1R homo-oligomerization is necessary for B1R maturation and trafficking to the cell surface. Modulating this mechanism may be a novel therapeutic avenue in inflammatory disease. PMID:23201435

  2. Myeloperoxidase Interacts with Endothelial Cell-Surface Cytokeratin 1 and Modulates Bradykinin Production by the Plasma Kallikrein-Kinin System

    PubMed Central

    Astern, Joshua M.; Pendergraft, William F.; Falk, Ronald J.; Jennette, J. Charles; Schmaier, Alvin H.; Mahdi, Fakhri; Preston, Gloria A.

    2007-01-01

    During an inflammatory state, functional myeloperoxidase (MPO) is released into the vessel as a result of intravascular neutrophil degradation. One mechanism of resulting cellular injury involves endothelial internalization of MPO, which causes oxidative damage and impairs endothelial signaling. We report the discovery of a protein that facilitates MPO internalization, cytokeratin 1 (CK1), identified using affinity chromatography and mass spectrometry. CK1 interacts with MPO in vitro, even in the presence of 100% human plasma, thus substantiating biological relevance. Immunofluorescent microscopy confirmed that MPO added to endothelial cells can co-localize with endogenously expressed CK1. CK1 acts as a scaffolding protein for the assembly of the vasoregulatory plasma kallikrein-kinin system; thus we explored whether MPO and high molecular weight kininogen (HK) reside on CK1 together or whether they compete for binding. The data support cooperative binding of MPO and HK on cells such that MPO masked the plasma kallikrein cleavage site on HK, and MPO-generated oxidants caused inactivation of both HK and kallikrein. Collectively, interactions between MPO and the components of the plasma kallikrein-kinin system resulted in decreased bradykinin production. This study identifies CK1 as a facilitator of MPO-mediated vascular responses and thus provides a new paradigm by which MPO affects vasoregulatory systems. PMID:17591979

  3. Differential effect of intranasally administrated kinin B1 and B2 receptor antagonists in Alzheimer's disease mice.

    PubMed

    Asraf, Keren; Torika, Nofar; Roasso, Ella; Fleisher-Berkovich, Sigal

    2016-04-01

    An Increasing body of evidence supports a critical role of brain inflammation in the pathogenesis of Alzheimer's disease. A principal aspect of the brain immune response to inflammation is the activation of microglia. It has been shown that the kinin system is activated during brain inflammation and previously we demonstrated that bradykinin B1 receptor agonist reduced microglial activation in vitro. The aim of the present study was to investigate the effects of bradykinin B1 or B2 receptor antagonists on microglial release of pro-inflammatory factors in BV2 microglia. In vivo, we focused on the effects of intranasally given kinin antagonists on amyloid burden and microglia/macrophage marker expression in brains of 5X familial Alzheimer's disease mice. The present data show that pharmacological antagonism of B1 receptor (R-715) but not B2 receptor (HOE-140) markedly increased nitric oxide and tumor necrosis factor alpha release from BV2 microglial cells. We also showed that intranasal treatment with R-715 but not HOE-140 of Alzheimer's mice enhanced amyloid beta burden and microglia/macrophages activation. Taken together, our data reveal a possible role for the bradykinin B1 receptor in neuroinflammation and in the control of Abeta accumulation in transgenic mice, possibly through regulation of glial cell responses. PMID:26556847

  4. Induction of vascular leakage through release of bradykinin and a novel kinin by cysteine proteinases from Staphylococcus aureus

    PubMed Central

    Imamura, Takahisa; Tanase, Sumio; Szmyd, Grzegorz; Kozik, Andrzej; Travis, James; Potempa, Jan

    2005-01-01

    Staphylococcus aureus is a major pathogen of gram-positive septic shock and frequently is associated with consumption of plasma kininogen. We examined the vascular leakage (VL) activity of two cysteine proteinases that are secreted by S. aureus. Proteolytically active staphopain A (ScpA) induced VL in a bradykinin (BK) B2-receptor–dependent manner in guinea pig skin. This effect was augmented by staphopain B (SspB), which, by itself, had no VL activity. ScpA also produced VL activity from human plasma, apparently by acting directly on kininogens to release BK, which again was augmented significantly by SspB. Intravenous injection of ScpA into a guinea pig caused BK B2-receptor–dependent hypotension. ScpA and SspB together induced the release of leucyl-methionyl-lysyl-BK, a novel kinin with VL and blood pressure–lowering activities that are equivalent to BK. Collectively, these data suggest that production of BK and leucyl-methionyl-lysyl-BK by staphopains is a new mechanism of S. aureus virulence and bacterial shock. Therefore, staphopain-specific inhibitors and kinin-receptor antagonists could be used to treat this disease. PMID:15897280

  5. Insect Bites and Stings

    MedlinePlus

    Most insect bites are harmless, though they sometimes cause discomfort. Bee, wasp, and hornet stings and fire ant bites usually hurt. Mosquito and flea bites usually itch. Insects can also spread diseases. In the United States, ...

  6. Insects: An Interdisciplinary Unit

    ERIC Educational Resources Information Center

    Leger, Heather

    2007-01-01

    The author talks about an interdisciplinary unit on insects, and presents activities that can help students practice communication skills (interpersonal, interpretive, and presentational) and learn about insects with hands-on activities.

  7. Respiration in Aquatic Insects.

    ERIC Educational Resources Information Center

    MacFarland, John

    1985-01-01

    This article: (1) explains the respiratory patterns of several freshwater insects; (2) describes the differences and mechanisms of spiracular cutaneous, and gill respiration; and (3) discusses behavioral aspects of selected aquatic insects. (ML)

  8. Insects and Scorpions

    MedlinePlus

    ... gov . Workplace Safety and Health Topics Insects & Scorpions Bees, Wasps, and Hornets Fire Ants Scorpions Additional Resources ... to outdoor workers. Stinging or biting insects include bees, wasps, hornets, and fire ants. The health effects ...

  9. Ecophysiology and insect herbivory

    SciTech Connect

    Clancy, K.M.; Wagner, M.R.; Reich, P.B.

    1995-07-01

    The relationship of insect herbivory to conifer physiology is examined. Aspects of nutrient assimilation, nutrient distribution, water stress, and climatic change are correlated to defoliation by insects. Other factors examined include plant age, density, structure, soils, and plant genotype.

  10. Acoustic Monitoring of Insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Farmers, grain elevator managers, and food processors often sample grain for insect damaged kernels and numbers of live adult insects but these easily obtained measurements of insect levels do not provide reliable estimates of the typically much larger populations of internally feeding immature inse...

  11. Exploring Sound with Insects

    ERIC Educational Resources Information Center

    Robertson, Laura; Meyer, John R.

    2010-01-01

    Differences in insect morphology and movement during singing provide a fascinating opportunity for students to investigate insects while learning about the characteristics of sound. In the activities described here, students use a free online computer software program to explore the songs of the major singing insects and experiment with making…

  12. Insects and Spiders.

    ERIC Educational Resources Information Center

    National Audubon Society, New York, NY.

    This set of teaching aids consists of nine Audubon Nature Bulletins, providing teachers and students with informational reading on insects and spiders. The bulletins have these titles: What Good Are Insects, How Insects Benefit Man, Life of the Honey Bee, Ants and Their Fascinating Ways, Mosquitoes and Other Flies, Caterpillars, Spiders and Silk,…

  13. Insects and Others.

    ERIC Educational Resources Information Center

    Mills, Richard

    1984-01-01

    Several ideas for observing insects and soil animals in the classroom are provided. Also provided are: (1) procedures for making insect cages with milk cartons; (2) suggestions for collecting and feeding insects; and (3) techniques for collecting and identifying soil animals. (BC)

  14. Interdisciplinary Outdoor Education, Insects.

    ERIC Educational Resources Information Center

    Orsborn, Edward E.

    This manual is a teacher's resource and guide book describing activities for elementary students involving the collecting, killing, preserving, and identification of insects. Most activities relate to collecting and identifying, but activities involving terrariums and hatcheries, finding hidden insects, and insect trapping are also described.…

  15. Sunflower insect pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Like other annual crops, sunflowers are fed upon by a variety of insect pests capable of reducing yields. Though there are a few insects which are considered consistent or severe (e.g., sunflower moth, banded sunflower moth, red sunflower seed weevil), many more insects are capable of causing proble...

  16. Kinin B1 and B2 receptor deficiency protects against obesity induced by a high-fat diet and improves glucose tolerance in mice

    PubMed Central

    Morais, Rafael L; Silva, Elton D; Sales, Vicência M; Filippelli-Silva, Rafael; Mori, Marcelo A; Bader, Michael; Pesquero, João B

    2015-01-01

    The kallikrein-kinin system is well known for its role in pain and inflammation, and has been shown recently by our group to have a role also in the regulation of energy expenditure. We have demonstrated that B1 receptor knockout (B1KO) mice are resistant to obesity induced by a high-fat diet (HFD) and that B1 receptor expression in adipocytes regulates glucose tolerance and predisposition to obesity. However, it is also known that in the absence of B1 receptor, the B2 receptor is overexpressed and can take over the function of its B1 counterpart, rendering uncertain the role of each kinin receptor in these metabolic effects. Therefore, we investigated the impact of ablation of each kinin receptor on energy metabolism using double kinin receptor knockout (B1B2KO) mice. Our data show that B1B2KO mice were resistant to HFD-induced obesity, with lower food intake and feed efficiency when compared with wild-type mice. They also had lower blood insulin and leptin levels and higher glucose tolerance after treatment with an HFD. Gene expression for tumor necrosis factor-alpha and C-reactive protein, which are important genes for insulin resistance, was reduced in white adipose tissue, skeletal muscle, and the liver in B1B2KO mice after the HFD. In summary, our data show that disruption of kinin B1 and B2 receptors has a profound impact on metabolic homeostasis in mice, by improving glucose tolerance and preventing HFD-induced obesity. These novel findings could pave the way for development of new pharmacological strategies to treat metabolic disorders such as insulin resistance and obesity. PMID:26346752

  17. InsectBase: a resource for insect genomes and transcriptomes.

    PubMed

    Yin, Chuanlin; Shen, Gengyu; Guo, Dianhao; Wang, Shuping; Ma, Xingzhou; Xiao, Huamei; Liu, Jinding; Zhang, Zan; Liu, Ying; Zhang, Yiqun; Yu, Kaixiang; Huang, Shuiqing; Li, Fei

    2016-01-01

    The genomes and transcriptomes of hundreds of insects have been sequenced. However, insect community lacks an integrated, up-to-date collection of insect gene data. Here, we introduce the first release of InsectBase, available online at http://www.insect-genome.com. The database encompasses 138 insect genomes, 116 insect transcriptomes, 61 insect gene sets, 36 gene families of 60 insects, 7544 miRNAs of 69 insects, 96,925 piRNAs of Drosophila melanogaster and Chilo suppressalis, 2439 lncRNA of Nilaparvata lugens, 22,536 pathways of 78 insects, 678,881 untranslated regions (UTR) of 84 insects and 160,905 coding sequences (CDS) of 70 insects. This release contains over 12 million sequences and provides search functionality, a BLAST server, GBrowse, insect pathway construction, a Facebook-like network for the insect community (iFacebook), and phylogenetic analysis of selected genes. PMID:26578584

  18. InsectBase: a resource for insect genomes and transcriptomes

    PubMed Central

    Yin, Chuanlin; Shen, Gengyu; Guo, Dianhao; Wang, Shuping; Ma, Xingzhou; Xiao, Huamei; Liu, Jinding; Zhang, Zan; Liu, Ying; Zhang, Yiqun; Yu, Kaixiang; Huang, Shuiqing; Li, Fei

    2016-01-01

    The genomes and transcriptomes of hundreds of insects have been sequenced. However, insect community lacks an integrated, up-to-date collection of insect gene data. Here, we introduce the first release of InsectBase, available online at http://www.insect-genome.com. The database encompasses 138 insect genomes, 116 insect transcriptomes, 61 insect gene sets, 36 gene families of 60 insects, 7544 miRNAs of 69 insects, 96 925 piRNAs of Drosophila melanogaster and Chilo suppressalis, 2439 lncRNA of Nilaparvata lugens, 22 536 pathways of 78 insects, 678 881 untranslated regions (UTR) of 84 insects and 160 905 coding sequences (CDS) of 70 insects. This release contains over 12 million sequences and provides search functionality, a BLAST server, GBrowse, insect pathway construction, a Facebook-like network for the insect community (iFacebook), and phylogenetic analysis of selected genes. PMID:26578584

  19. Insect Barcode Information System

    PubMed Central

    Pratheepa, Maria; Jalali, Sushil Kumar; Arokiaraj, Robinson Silvester; Venkatesan, Thiruvengadam; Nagesh, Mandadi; Panda, Madhusmita; Pattar, Sharath

    2014-01-01

    Insect Barcode Information System called as Insect Barcode Informática (IBIn) is an online database resource developed by the National Bureau of Agriculturally Important Insects, Bangalore. This database provides acquisition, storage, analysis and publication of DNA barcode records of agriculturally important insects, for researchers specifically in India and other countries. It bridges a gap in bioinformatics by integrating molecular, morphological and distribution details of agriculturally important insects. IBIn was developed using PHP/My SQL by using relational database management concept. This database is based on the client– server architecture, where many clients can access data simultaneously. IBIn is freely available on-line and is user-friendly. IBIn allows the registered users to input new information, search and view information related to DNA barcode of agriculturally important insects.This paper provides a current status of insect barcode in India and brief introduction about the database IBIn. Availability http://www.nabg-nbaii.res.in/barcode PMID:24616562

  20. Biostability of polyether-urethane scaffolds: a comparison of two novel processing methods and the effect of higher gamma-irradiation dose.

    PubMed

    Haugen, H; Gerhardt, L C; Will, J; Wintermantel, E

    2005-05-01

    This article deals with enzyme-induced biodegradation behavior of thermoplastic polyether-urethane (TPU). Porous scaffolds were processed by a new foaming method applied in hot pressing and injection molding. The scaffolds were subsequently gamma sterilized. The samples were incubated with cholesterol esterase (CE) for 28 days to simulate an enzymatic degradation order to assess polymer biostability. The main focus of degradation products was the most toxic one: methylene dianiline (MDA). LC/MS was used to separate the breakdown products and to identify possible MDA amounts. The results showed that (a) the hot-pressed sample released an MDA amount almost twice as large (0.26 ng +/- 0.008) as that of the injection-molded samples (0.15 ng +/- 0.003) after incubation with enzyme activity in the physiological range, and (b) a tenfold increase in CE activity revealed considerably higher MDA amounts (7540.0 ng +/- 0.004). This enzyme concentration is physiologically unlikely, however, but may occur for extreme high inflammation behavior. Even for extremely high levels of CE enzyme, the scaffold will not discharge MDA above toxic levels. The injection-molded samples sterilized at 25 kGy seem to represent the most promising processing method. Therefore, the new injection-molding foaming process of polyether-urethane can be considered appropriate for use as a biomaterial. PMID:15756657

  1. Mediation by B1 and B2 receptors of vasodepressor responses to intravenously administered kinins in anaesthetized dogs.

    PubMed

    Nakhostine, N; Ribuot, C; Lamontagne, D; Nadeau, R; Couture, R

    1993-09-01

    1. Vasodepressor responses to intravenous (i.v.) injection of bradykinin (BK) and des-Arg9-BK, a selective B1 kinin receptor agonist, were characterized following i.v. pretreatment with selective B1 ([Leu8]-des-Arg9-BK) and B2 (Hoe 140) kinin receptor antagonists in anaesthetized dogs. 2. Des-Arg9-BK (0.05-3.3 nmol kg-1) produced dose-dependent decreases in mean arterial blood pressure with a ED50 0.4 nmol kg-1. The vasodepressor effects evoked by des-Arg9-BK (0.6 nmol kg-1) and BK (0.2 nmol kg-1) were greater after i.v. and i.a. injections, respectively. 3. The vasodepressor response to BK (0.6 nmol kg-1) but not to des-Arg9-BK (0.6 nmol kg-1) was significantly (P < 0.001) blocked by pretreatment with the B2 receptor antagonist, Hoe 140. 4. The vasodepressor response to des-Arg9-BK (0.6 nmol kg-1) but not to BK (0.6 nmol kg-1) was significantly (P < 0.001) reduced by pretreatment with the selective B1 receptor antagonist, [Leu8]-des-Arg9-BK. Although both B1 and B2 receptor antagonists caused a transient fall in blood pressure, their inhibitory action was unlikely to be related to a desensitization mechanism. 5. Inhibition of prostaglandin synthesis with indomethacin prevented the vasodepressor response induced by arachidonic acid (1 mg kg-1, i.v.) but not that to BK or des-Arg9-BK (0.6 nmol kg-1). 6. These results suggest, firstly, that the vasodepressor responses to i.v. BK and des-Arg9-BK are mediated by the activation of B2 and B1 receptors, respectively; secondly, that prostaglandins are not involved in the vasodepressor responses to kinins.These findings provide pharmacological evidence for the existence of functionally active B1 receptors in canine cardiovascular homeostasis. PMID:8220916

  2. [Kallikrein-Kinin System. Long History and Present. (To 90th Anniversary of Discovery of the System)].

    PubMed

    Yarovaya, G A; Neshkova, E A

    2015-01-01

    The kallikrein-kinin system (KKS) is the key proteolytic system participating in control of a wide spectrum of physiological functions and the development of many pathological conditions. This explains great interest in structures, functions and molecular biology of separate components of the system, molecular mechanisms of their interaction and relationship with other regulatory systems. The information in this field for the last two decades clarifies the role of KKS in morphogenesis of cells, regulation of smooth muscular contractility of some organs, decrease of blood pressure, increase of vascular permeability, the development of inflammation, transformation of cells and the other functions of both physiological and pathological processes. Essential progress in understanding of functions KKS was made by the discovery and study of bradykinin receptors, cloning of kininogen and kallikrein encoding genes, revealing of domain structure of kininogen, prekallikrein and some kininases and decoding of mechanisms of contact phase of proteolytic system activation in blood plasma. PMID:26502604

  3. Characterization of a novel proinflammatory effect mediated by BK and the kinin B₂ receptor in human preadipocytes.

    PubMed

    Catalioto, Rose-Marie; Valenti, Claudio; Liverani, Luca; Giuliani, Sandro; Maggi, Carlo Alberto

    2013-08-15

    Obesity and adipose tissue contribute to local and systemic inflammation. However the role of the inflammatory mediator bradykinin (BK) in this context is not known. We therefore evaluated the effect of BK on adipokines secretion in human preadipocytes during the course of differentiation and characterized the receptors involved. Results obtained from antibody array and ELISA experiments showed that several adipokines are released by human preadipocytes under basal conditions while BK specifically stimulated the production of interleukin(IL)-6 and IL-8. The effect of BK diminished with the progression of differentiation, being almost inactive on adipocytes. In preadipocytes, BK also induced a rapid and transient [Ca²⁺](i) mobilization, a rapid and sustained increase in ERK1/2 activation and enhanced forskolin-stimulated cAMP accumulation. BK was without effect on cell proliferation and viability as assessed by bromodeoxyuridine incorporation, WST-1 conversion, or lactate dehydrogenase leakage and was without effect on adipogenesis as measured by triglyceride accumulation, GPDH activity and leptin release. The B₁ receptor agonist, Lys-[des-Arg⁹]-BK, displayed poor activity or was without effect while overall BK effects were prevented by the selective B₂ receptor antagonist, fasitibant chloride, but not by the B₁ selective antagonist, Lys-[Leu⁸][des-Arg⁹]-BK. Immunoblot analysis and immunofluorescence studies showed that the kinin B₂ receptor was essentially expressed at the beginning of the differentiation program. In conclusion, human preadipocytes expressed kinin B₂ receptors linked to multiple signaling pathways, IL-6 and IL-8 production, and BK proinflammatory response in adipose tissue could be prevented by fasitibant chloride. PMID:23796753

  4. Participation of kinins in the captopril-induced inhibition of intimal hyperplasia caused by interruption of carotid blood flow in the mouse

    PubMed Central

    Emanueli, Costanza; Salis, Maria Bonaria; Figueroa, Carlos; Chao, Julie; Chao, Lee; Gaspa, Leonardo; Capogrossi, Maurizio C; Madeddu, Paolo

    2000-01-01

    In the rat balloon injury model, angiotensin-converting enzyme (ACE) inhibitors prevent vascular remodelling by inhibiting angiotensin II generation and kinin breakdown. We investigated if ACE inhibition also prevents the structural vascular responses to disruption of carotid artery blood flow and if kinin potentiation plays a role in such a protection. Morphometric analysis of the structural alterations caused by ligation of the left carotid artery was performed 14 days after surgery in J129Sv wild-type mice (B2+/+) drinking normal tap water or water containing captopril (120 mg kg−1 per day). In addition, the effect of captopril on vascular remodelling was tested in B2+/+ given the bradykinin (BK) B1 receptor antagonist des-Arg9-[Leu8]-BK (DALBK, 50 nmol kg−1 per day, intraperitoneally) or the BK B2 receptor antagonist D-Arg,[Hyp3,Thi5D-Tic7,Oic8]-BK (icatibant, 1 μmol kg−1 per day, intraperitoneally), and in B2 receptor gene knockout mice (B2−/−). Interruption of blood flow resulted in carotid artery intimal hyperplasia and media thickening in untreated B2+/+, these responses being partially suppressed by captopril. The inhibition of intimal thickening exerted by captopril was reduced in B2+/+ given DALBK or icatibant (P<0.05 for both comparisons) as well as in B2−/− (P<0.05). Neither antagonism of kinin receptors nor disruption of the B2 receptor gene altered the suppressive effect of captopril on media thickening. The protection of vascular wall structure was independent of the reduction in blood pressure by captopril. These results demonstrate that kinins participate in the inhibitory effect of captopril on intimal hyperplasia via B1 and B2 receptor signalling. Our findings may have important implications in treating vascular remodelling evoked by altered shear stress conditions. PMID:10882392

  5. [The blood kinin system in persons exposed to ionizing radiation as a result of the accident at the Chernobyl Atomic Electric Power Station].

    PubMed

    Klimenko, V I; Liubarets, T F

    1993-01-01

    Condition of blood kinin system was studied in persons engaged on liquidation of Chernobyl accident sequels in 1986 and subjected to levels of ionizing radiation ranging up to 1 Gy. Activation of kininogenesis in such persons manifested in rise of the initial protaminolytic blood activity, partial decrease of prekallikrein level and imbalance on the part of the blood inhibitory potential in the form of alpha-2-macroglobulin level fall and increase of general blood antiproteolytic activity. PMID:8209496

  6. Sterile Insect Quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter discusses the history of the development of quality control tchnology, the principles and philosophy of assessing insect quality, and the relative importance of the various parameters used to assess insect quality in the context of mass-rearing for the SIT. Quality control is most devel...

  7. Corazonin in insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corazonin is a peptidergic neurohormone of insects which is expressed in neurosecretory neurons of the pars lateralis of the protocerebrum and transported via nervi corpus cardiaci in the storage lobes of the corpora cardiaca. This peptide occurs with a single isofomr in all insects studied so far,...

  8. Insects: Bugged Out!

    ERIC Educational Resources Information Center

    Piehl, Kathy

    2011-01-01

    Insects really need no introduction. They have lived on earth much longer than humans and vastly outnumber people and all other animal species combined. People encounter them daily in their houses and yards. Yet, when children want to investigate insects, books can help them start their explorations. "Paleo Bugs" carries readers back to the time…

  9. Insects and Bugs

    ERIC Educational Resources Information Center

    Sutherland, Karen

    2009-01-01

    They have been around for centuries. They sting, they bite. They cause intense itching or painful sores. They even cause allergic reactions and sometimes death. There are two types of insects that are pests to humans--those that sting and those that bite. The insects that bite do so with their mouths and include mosquitoes, chiggers, and ticks.…

  10. Sugarcane insect update

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect are an important group of pests affecting sugarcane production. Agricultural consultants play an important role is assisting sugarcane farmers to choose the most appropriated means of managing damaging infestations of insects in their crop. In this presentation, information will be presented ...

  11. Effects on Insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of controlled and modified atmospheres on insects is reviewed and summarized in this chapter. Traditionally, controlled and modified atmospheres are used to store and preserve fresh fruits and vegetables. The effects on insects and the potential of these treatments are secondary to the...

  12. Principal Areas of Insect Research

    ERIC Educational Resources Information Center

    Williams, Carroll M.

    1973-01-01

    Research for insect control has been quite complex. However, recent knowledge of using insect hormones against them has opened new vistas for producing insecticides which may be harmless to human population. Current areas of insect research are outlined. (PS)

  13. Involvement of Kallikrein-Kinin System on Cardiopulmonary Alterations and Inflammatory Response Induced by Purified Aah I Toxin from Scorpion Venom.

    PubMed

    Medjadba, Wafa; Martin-Eauclaire, Marie-France; Laraba-Djebari, Fatima

    2016-02-01

    Bradykinins are released from kininogen by kallikrein. They increase capillary lung permeability after their binding to β1 and especially β2 receptors before being metabolized by kininase enzyme. This study was performed to evaluate cardiopulmonary damages and inflammatory response on injected rats with Aah I toxin of scorpion venom and the involvement of Kallikrein-Kinin system in this pathogenesis. Obtained results revealed that Aah I toxin induces inflammatory cell infiltration accompanied by cellular peroxidase activities, a release of cytokine levels, pulmonary and myocardial damage, with altered metabolic activities and imbalanced redox status. Administration of aprotinin (bradykinin inhibitor) and especially icatibant (bradykinin β2 receptor antagonist) seemed to be able to protect animals against the toxicity of Aah I; nevertheless, the use of captopril (kininase II inhibitor) reduced partially some cardiac disorders. These findings indicate that the kallikrein-kinin system may contribute to the physiopathological effect and lung edema formation induced by toxin, which suggests a potential use of drugs with significant anti-kinin properties. PMID:26361946

  14. Mycetocyte symbiosis in insects.

    PubMed

    Douglas, A E

    1989-11-01

    1. Non-pathogenic microorganisms, known as mycetocyte symbionts, are located in specialized 'mycetocyte' cells of many insects that feed on nutritionally unbalanced or poor diets. The insects include cockroaches, Cimicidae and Lygaeidae (Heteroptera), the Homoptera, Anoplura, the Diptera Pupiparia, some formicine ants and many beetles. 2. Most mycetocyte symbionts are prokaryotes and a great diversity of forms has been described. None has been cultured in vitro and their taxonomic position is obscure. Yeasts have been reported in Cerambycidae and Anobiidae (Coleoptera) and a few planthoppers. They are culturable and those in anobiids have been assigned to the genus Torulopsis. 3. The mycetocyte cells may be associated with the gut, lie free in the abdominal haemocoel or be embedded in the fat body of the insect. The mycetocytes are large polyploid cells which rarely divide and the symbionts are restricted to their cytoplasm. 4. The mycetocyte symbionts are transmitted maternally from one insect generation to the next. In many beetles (Anobiidae, Cerambycidae, Chrysomelidae and cleonine Curculionidae), the microoganisms are smeared onto the eggs and consumed by the hatching larvae. In other insects, they are transferred from mycetocytes to oocytes in the ovary, a process known as transovarial transmission. The details of transmission in the different insect groups vary with the age of the mother (adult, larva or embryo) at which symbiont transfer to the ovary is initiated; whether isolated symbionts or intact mycetocytes are transferred; and the site of entry of symbionts to the egg (anterior, posterior or apolar). 5. Within an individual insect, the biomass of symbionts varies in a regular fashion with age, weight and sex of the insect. Suppression of symbiont growth rate and lysis of 'excess' microorganisms may contribute to the regulation of symbionts (including freshly-isolated preparations of unculturable forms) are used to investigate interactions between the

  15. Beneficial Insects and Insect Pollinators on Milkweed in South Georgia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect pollinators are essential for the reproduction of more than two-thirds of the world’s crops, and beneficial insects play an important role in managing pest insects in agricultural farmscapes. These insects depend on nectar for their survival in these farmscapes. The flowers of tropical milkwe...

  16. Insects and climate change

    SciTech Connect

    Elias, S.A. )

    1991-09-01

    In this article the author describes some of the significant late glacial and Holocene changes that occurred in the Rocky Mountains, including the regional extirpation of certain beetle species. The fossil data presented here summarize what is known about regional insect responses to climate change in terms of species stability and geographic distribution. To minimize potential problems of species interactions (i.e., insect-host plant relationships, host-parasite relationships, and other interactions that tie a particular insect species' distribution to that of another organism), only predators and scavengers are discussed. These insects respond most rapidly to environmental changes, because for the most part they are not tied to any particular type of vegetation.

  17. Insect hemolymph clotting.

    PubMed

    Dushay, Mitchell S

    2009-08-01

    The clot's appearance in different large-bodied insects has been described, but until recently, little was known about any insect clot's molecular makeup, and few experiments could directly test its function. Techniques have been developed in Drosophila (fruit fly) larvae to identify clotting factors that can then be tested for effects on hemostasis, healing, and immunity. This has revealed unanticipated complexity in the hemostatic mechanisms in these larvae. While the clot's molecular structure is not yet fully understood, progress is being made, and the loss of clotting factors has been shown to cause subtle immune defects. The few similarities between coagulation in different insect species and life stages, and the current state of knowledge about coagulation in insects are discussed. PMID:19418022

  18. Feeding the insect industry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article reports the use of insect colloidal artificial diets suitable for the rearing of economically important arthropods, such as Lygus lineolaris, Lygus hesperus, Coleomegilla maculata, and Phytoseiulus persimilis The different diets contain key nutrients such as proteins, carbohydrates, vit...

  19. Important Insect Pests of Fruit - Important Insect Pests of Nuts - Field Crop Insect Pests - Insect Pests of Vegetable Crops.

    ERIC Educational Resources Information Center

    Gesell, Stanley G.; And Others

    This document consists of four agriculture extension service publications from Pennsylvania State University. The titles are: (1) Important Insect Pests of Fruit; (2) Important Insect Pests of Nuts; (3) Field Crop Insect Pests; and (4) Insect Pests of Vegetable Crops. The first publication gives the hosts, injury, and description of 22 insect…

  20. Evolution of the Insects

    NASA Astrophysics Data System (ADS)

    Grimaldi, David; Engel, Michael S.

    2005-05-01

    This book chronicles the complete evolutionary history of insects--their living diversity and relationships as well as 400 million years of fossils. Introductory sections cover the living species diversity of insects, methods of reconstructing evolutionary relationships, basic insect structure, and the diverse modes of insect fossilization and major fossil deposits. Major sections then explore the relationships and evolution of each order of hexapods. The volume also chronicles major episodes in the evolutionary history of insects from their modest beginnings in the Devonian and the origin of wings hundreds of millions of years before pterosaurs and birds to the impact of mass extinctions and the explosive radiation of angiosperms on insects, and how they evolved into the most complex societies in nature. Whereas other volumes focus on either living species or fossils, this is the first comprehensive synthesis of all aspects of insect evolution. Illustrated with 955 photo- and electron- micrographs, drawings, diagrams, and field photos, many in full color and virtually all of them original, this reference will appeal to anyone engaged with insect diversity--professional entomologists and students, insect and fossil collectors, and naturalists. David Grimaldi and Michael S. Engel have collectively published over 200 scientific articles and monographs on the relationships and fossil record of insects, including 10 articles in the journals Science, Nature, and Proceedings of the National Academy of Sciences. David Grimaldi is curator in the Division of Invertebrate Zoology, American Museum of Natural History and adjunct professor at Cornell University, Columbia University, and the City University of New York. David Grimaldi has traveled in 40 countries on 6 continents, collecting and studying recent species of insects and conducting fossil excavations. He is the author of Amber: Window to the Past (Abrams, 2003). Michael S. Engel is an assistant professor in the

  1. Exploring Insect Vision

    ERIC Educational Resources Information Center

    Damonte, Kathleen

    2005-01-01

    A fly is buzzing around in the kitchen. You sneak up on it with a flyswatter, but just as you get close to it, it flies away. What makes flies and other insects so good at escaping from danger? The fact that insects have eyesight that can easily detect moving objects is one of the things that help them survive. In this month's Science Shorts,…

  2. Insect--plant adaptations.

    PubMed

    Southwood, T R

    1984-01-01

    The adaptation of insects to plants probably commenced in the early Permian period, though most current associations will be more recent. A major burst of adaptation must have followed the rise of the Angiosperms in the Cretaceous period, though some particular associations are as recent as this century. Living plants form a large proportion of the potential food in most habitats, though insects have had to overcome certain general hurdles to live and feed on them. Insects affect the reproduction and survival of plants, and thus the diversity of plant secondary chemicals may have evolved as a response. Where an insect species has a significant effect on a plant species that is its only host, coevolution may be envisaged. A spectacular example is provided by Heliconius butterflies and passion flower vines, studied by L.E. Gilbert and others. But such cases may be likened to 'vortices in the evolutionary stream': most plant species are influenced by a range of phytophagous insects so that selection will be for general defences--a situation termed diffuse coevolution. Evidence is presented on recent host-plant shifts to illustrate both the restrictions and the flexibility in current insect-plant associations. PMID:6559112

  3. Insect immunology and hematopoiesis.

    PubMed

    Hillyer, Julián F

    2016-05-01

    Insects combat infection by mounting powerful immune responses that are mediated by hemocytes, the fat body, the midgut, the salivary glands and other tissues. Foreign organisms that have entered the body of an insect are recognized by the immune system when pathogen-associated molecular patterns bind host-derived pattern recognition receptors. This, in turn, activates immune signaling pathways that amplify the immune response, induce the production of factors with antimicrobial activity, and activate effector pathways. Among the immune signaling pathways are the Toll, Imd, Jak/Stat, JNK, and insulin pathways. Activation of these and other pathways leads to pathogen killing via phagocytosis, melanization, cellular encapsulation, nodulation, lysis, RNAi-mediated virus destruction, autophagy and apoptosis. This review details these and other aspects of immunity in insects, and discusses how the immune and circulatory systems have co-adapted to combat infection, how hemocyte replication and differentiation takes place (hematopoiesis), how an infection prepares an insect for a subsequent infection (immune priming), how environmental factors such as temperature and the age of the insect impact the immune response, and how social immunity protects entire groups. Finally, this review highlights some underexplored areas in the field of insect immunobiology. PMID:26695127

  4. Antagonism by mefenamic and flufenamic acids of the bronchoconstrictor action of kinins in the guinea-pig

    PubMed Central

    Collier, H. O. J.; Shorley, Patricia G.

    1963-01-01

    In the guinea-pig, N-(2,3-xylyl)anthranilic acid (mefenamic acid) and N-(α,α,α-trifluoro-m-tolyl)anthranilic acid (flufenamic acid), two new anti-inflammatory agents, antagonize bronchoconstriction, but not hypotension, produced by kinins. They do not reduce bronchoconstrictor responses to acetylcholine, histamine or 5-hydroxytryptamine. The antibradykinin potencies of mefenamic and flufenamic acids approximately equal that of acetylsalicylic acid when given intravenously and of phenylbutazone when given into the duodenum. After administration of mefenamic and flufenamic acids, the bronchoconstrictor response can be restored by higher doses of bradykinin. The quantitative relationship between the intravenous dose of sodium mefenamate or flufenamate and the dose of bradykinin needed to surmount either antagonist in bronchial muscle fulfils the requirements for competitive antagonism. Antagonism by calcium acetylsalicylate can also be surmounted with higher doses of bradykinin, but in this instance the relationship of antagonist to agonist fulfils requirements for competitive antagonism only at the lower part of the dose range. PMID:14022332

  5. Beneficial effects of kinin B1 receptor antagonism on plasma fatty acid alterations and obesity in Zucker diabetic fatty rats.

    PubMed

    Talbot, Sébastien; Dias, Jenny Pena; El Midaoui, Adil; Couture, Réjean

    2016-07-01

    Kinins are the endogenous ligands of the constitutive B2 receptor (B2R) and the inducible B1 receptor (B1R). Whereas B2R prevents insulin resistance, B1R is involved in insulin resistance and metabolic syndrome. However, the contribution of B1R in type 2 diabetes associated with obesity remains uncertain. The aim of the present study was to examine the impact of 1-week treatment with a selective B1R antagonist (SSR240612, 10 mg/kg per day, by gavage) on hyperglycemia, hyperinsulinemia, leptinemia, body mass gain, and abnormal plasma fatty acids in obese Zucker diabetic fatty (ZDF) rats. Treatment with SSR240612 abolished the body mass gain and reduced polyphagia, polydipsia, and plasma fatty acid alterations in ZDF rats without affecting hyperglycemia, hyperinsulinemia, and hyperleptinemia. The present study suggests that the upregulated B1R plays a role in body mass gain and circulating fatty acid alterations in ZDF rats. However, mechanisms other than B1R induction would be implicated in glucose metabolism disorder in ZDF rats, based on the finding that SSR240612 did not reverse hyperglycemia and hyperinsulinemia. PMID:27172260

  6. Contact activation of kallikrein-kinin system by superparamagnetic iron oxide nanoparticles in vitro and in vivo

    PubMed Central

    Simberg, Dmitri; Zhang, Wan-Ming; Merkulov, Sergei; McCrae, Keith; Park, Ji-Ho; Sailor, Michael J.; Ruoslahti, Erkki

    2009-01-01

    Previously we reported that plasma kallikrein and high molecular weight kininogen attach to the surface of dextran-coated superparamagnetic iron oxide nanoparticles (SPIONs) through the incompletely covered iron oxide core (Simberg et al., Biomaterials, 2009). Here we show that SPIONs also activate kallikrein-kinin system in vitro and in vivo. The serine protease activity of kallikrein was stably associated with SPIONs and could be detected on the nanoparticles even after extensive washing steps. The enzymatic activity was not detectable in kininogen-deficient and Factor XII-deficient plasma. The enzymatic activation could be blocked by precoating SPIONs with histidine-rich Domain 5 (D5) of kininogen. Importantly, the kallikrein activity was detectable in plasma of SPION-injected, but not of D5/SPION-injected mice. Tumor-targeted SPIONs when injected into kininogen-deficient and control mice, produced high levels of vascular clotting in tumors, suggesting that kallikrein activation is not responsible for the nanoparticle-induced thrombosis. These data could help in understanding the toxicity of nanomaterials and could be used in designing nanoparticles with controlled enzymatic activity. PMID:19508879

  7. The Role of Plasma Kallikrein-Kinin Pathway in the Development of Diabetic Retinopathy: Pathophysiology and Therapeutic Approaches.

    PubMed

    Abdulaal, Marwan; Haddad, Nour Maya N; Sun, Jennifer K; Silva, Paolo S

    2016-01-01

    Diabetic retinal disease is characterized by a series of retinal microvascular changes and increases in retinal vascular permeability that lead to development of diabetic retinopathy (DR) and diabetic macular edema (DME), respectively. Current treatment strategies for DR and DME are mostly limited to vascular endothelial growth factor (VEGF) inhibitors and laser photocoagulation. These treatment modalities are not universally effective in all patients, and potential side effects persist in a significant portion of patients. The plasma kallikrein-kinin system (KKS) is one of the pathways that has been identified in the vitreous in proliferative DR and DME. Preclinical studies have shown that the activation of intraocular KKS induces retinal vascular permeability, vasodilation, and retinal thickening. Proteomic analysis from vitreous of eyes with DME has shown that KKS and VEGF pathways are potentially independent biologic pathways. Furthermore, proteins associated with DME in the vitreous were significantly more correlated with the KKS pathway compared to VEGF pathway. Preclinical experiments on diabetic animals showed that inhibition of KKS components was found to be an effective approach to decrease retinal vascular permeability. An initial phase I human trial of a novel plasma kallikrein inhibitor for the treatment of DME is currently ongoing to test the safety of this approach and serves as an initial step in the translation of basic science discovery into an innovative clinical intervention. PMID:26959125

  8. Insect bite reactions.

    PubMed

    Singh, Sanjay; Mann, Baldeep Kaur

    2013-01-01

    Insects are a class of living creatures within the arthropods. Insect bite reactions are commonly seen in clinical practice. The present review touches upon the medically important insects and their places in the classification, the sparse literature on the epidemiology of insect bites in India, and different variables influencing the susceptibility of an individual to insect bites. Clinical features of mosquito bites, hypersensitivity to mosquito bites Epstein-Barr virus NK (HMB-EBV-NK) disease, eruptive pseudoangiomatosis, Skeeter syndrome, papular pruritic eruption of HIV/AIDS, and clinical features produced by bed bugs, Mexican chicken bugs, assassin bugs, kissing bugs, fleas, black flies, Blandford flies, louse flies, tsetse flies, midges, and thrips are discussed. Brief account is presented of the immunogenic components of mosquito and bed bug saliva. Papular urticaria is discussed including its epidemiology, the 5 stages of skin reaction, the SCRATCH principle as an aid in diagnosis, and the recent evidence supporting participation of types I, III, and IV hypersensitivity reactions in its causation is summarized. Recent developments in the treatment of pediculosis capitis including spinosad 0.9% suspension, benzyl alcohol 5% lotion, dimethicone 4% lotion, isopropyl myristate 50% rinse, and other suffocants are discussed within the context of evidence derived from randomized controlled trials and key findings of a recent systematic review. We also touch upon a non-chemical treatment of head lice and the ineffectiveness of egg-loosening products. Knockdown resistance (kdr) as the genetic mechanism making the lice nerves insensitive to permethrin is discussed along with the surprising contrary clinical evidence from Europe about efficacy of permethrin in children with head lice carrying kdr-like gene. The review also presents a brief account of insects as vectors of diseases and ends with discussion of prevention of insect bites and some serious adverse effects

  9. Enterococci in Insects

    PubMed Central

    Martin, Jonathan D.; Mundt, J. Orvin

    1972-01-01

    Enterococci were obtained from 213 of 403 insects cultured during a 14-month period, in numbers from 103 to 3 × 107/g of insect. Insects were taken only from nonurban, wild, and cultivated fields and woods. In species of insects carrying them, enterococci were not always present in every individual cultured, and often more than one species of enterococcus occurred within a species. Enterococci were obtained from certain insects taken in the field during the dormant season, suggesting their role as overwintering agents. They were generally present in species feeding on nectar, succulent plant parts, and on and ir forest litter, but not from insects feeding on less succulent leaves and stems. Streptococcus faecalis was recovered from 32%, Streptococcus faecium from 22.4%, and Streptococcus faecium var. casseliflavus from 43.5% of members of the 37 taxa of insects. S. faecalis and S. faecium var. casseliflavus exhibit a high percent of conformity to the properties published for them. The heterogeneity in properties of S. faecium is similar to that found for the species taken from plants. Many fail to grow in broth at 45 C or in broth containing 6.5% NaCl; 50% of the cultures ferment both melezitose and melibiose, and a few ferment neither sugar. The remainder ferment melibiose only. Failure to reduce methylene blue in milk by S. faecalis and S. faecium is correlated with the inability to ferment lactose. More than 93% of the cultures of S. faecalis digest casein in milk from the top downward, following the production of a soft, flowing curd. Because this property is not characteristic of S. faecalis taken from humans, the reaction in litmus milk is suggested as a means of differentiation between cultures of remote and innocent origin in nature and recent, human pollution. PMID:4628796

  10. Interactive contribution of NK(1) and kinin receptors to the acute inflammatory oedema observed in response to noxious heat stimulation: studies in NK(1) receptor knockout mice.

    PubMed

    Rawlingson, A; Gerard, N P; Brain, S D

    2001-12-01

    1. Scald injury in Sv129+C57BL/6 mice induced a temperature and time dependent oedema formation as calculated by the extravascular accumulation of [(125)I]-albumin. Oedema formation was suppressed in NK(1) knockout mice compared to wildtypes at 10 (P<0.01) and 30 min (P<0.001). However, at 60 min a similar degree of extravasation was observed in the two groups. 2. Kinin B(1) (des-Arg(10) Hoe 140; 1 micromol kg(-1)) and B(2) (Hoe 140; 100 nmol kg(-1)) antagonists caused an inhibition of oedema in wildtype mice at 10 and 30 min (P<0.001), but not at 60 min or at 30 min in NK(1) receptor knockout mice. 3. The inhibition of thermic oedema by des-Arg(10) Hoe 140 was reversed by des-Arg(9) bradykinin (0.1 micromol kg(-1); P<0.01) and also observed with a second B(1) receptor antagonist (des-Arg(9) Leu(8) bradykinin; 3 micromol kg(-1); P<0.01). Furthermore des-Arg(10) Hoe 140 had no effect on capsaicin (200 microg ear(-1)) ear oedema, but this was significantly reduced with Hoe 140 (P<0.05). 4. Scalding induced a large neutrophil accumulation at 4 h, as assessed by myeloperoxidase assay (P<0.001). This was not suppressed by NK(1) receptor deletion or kinin antagonists. 5. These results confirm an essential role for the NK(1) receptor in mediating the early, but not the delayed phase of oedema formation or neutrophil accumulation in response to scalding. The results also demonstrate a pivotal link between the kinins and sensory nerves in the microvascular response to burn injury, and for the first time show a rapid involvement of the B(1) receptor in murine skin. PMID:11739258

  11. Behavioral Immunity in Insects

    PubMed Central

    de Roode, Jacobus C.; Lefèvre, Thierry

    2012-01-01

    Parasites can dramatically reduce the fitness of their hosts, and natural selection should favor defense mechanisms that can protect hosts against disease. Much work has focused on understanding genetic and physiological immunity against parasites, but hosts can also use behaviors to avoid infection, reduce parasite growth or alleviate disease symptoms. It is increasingly recognized that such behaviors are common in insects, providing strong protection against parasites and parasitoids. We review the current evidence for behavioral immunity in insects, present a framework for investigating such behavior, and emphasize that behavioral immunity may act through indirect rather than direct fitness benefits. We also discuss the implications for host-parasite co-evolution, local adaptation, and the evolution of non-behavioral physiological immune systems. Finally, we argue that the study of behavioral immunity in insects has much to offer for investigations in vertebrates, in which this topic has traditionally been studied. PMID:26466629

  12. Insect Repellents: Protect Your Child from Insect Bites

    MedlinePlus

    ... Español Text Size Email Print Share Choosing an Insect Repellent for Your Child Page Content Article Body Mosquitoes , ... sunscreen needs to be reapplied often. Reactions to Insect Repellents If you suspect that your child is having ...

  13. Cognition in insects

    PubMed Central

    Webb, Barbara

    2012-01-01

    A traditional view of cognition is that it involves an internal process that represents, tracks or predicts an external process. This is not a general characteristic of all complex neural processing or feedback control, but rather implies specific forms of processing giving rise to specific behavioural capabilities. In this paper, I will review the evidence for such capabilities in insect navigation and learning. Do insects know where they are, or do they only know what to do? Do they learn what stimuli mean, or do they only learn how to behave? PMID:22927570

  14. Protecting Yourself from Stinging Insects

    MedlinePlus

    ... at risk of being stung by flying insects (bees, wasps, and hornets) and fire ants. While most ... by several stinging insects, run to get away. (Bees release a chemical when they sting, which attracts ...

  15. Investigation--Insects!

    ERIC Educational Resources Information Center

    Fay, Janice

    2000-01-01

    Presents activities on insects for second grade students. In the first activity, students build a butterfly garden. In the second activity, students observe stimuli reactions with mealworms in the larval stage. Describes the assessment process and discusses the effects of pollution on living things. (YDS)

  16. Fluorescence in insects

    NASA Astrophysics Data System (ADS)

    Welch, Victoria L.; Van Hooijdonk, Eloise; Intrater, Nurit; Vigneron, Jean-Pol

    2012-10-01

    Fluorescent molecules are much in demand for biosensors, solar cells, LEDs and VCSEL diodes, therefore, considerable efforts have been expended in designing and tailoring fluorescence to specific technical applications. However, naturally occurring fluorescence of diverse types has been reported from a wide array of living organisms: most famously, the jellyfish Aequorea victoria, but also in over 100 species of coral and in the cuticle of scorpions, where it is the rule, rather than the exception. Despite the plethora of known insect species, comparatively few quantitative studies have been made of insect fluorescence. Because of the potential applications of natural fluorescence, studies in this field have relevance to both physics and biology. Therefore, in this paper, we review the literature on insect fluorescence, before documenting its occurrence in the longhorn beetles Sternotomis virescens, Sternotomis variabilis var. semi rufescens, Anoplophora elegans and Stellognatha maculata, the tiger beetles Cicindela maritima and Cicindela germanica and the weevil Pachyrrhynchus gemmatus purpureus. Optical features of insect fluorescence, including emitted wavelength, molecular ageing and naturally occurring combinations of fluorescence with bioluminescence and colour-producing structures are discussed.

  17. Insects. Thematic Unit.

    ERIC Educational Resources Information Center

    Gosnell, Kathee

    This book is a captivating whole-language thematic unit about the study of insects, relating it to our understanding of the past and our hopes for using our knowledge in the present to balance the ecosystem in the future. It contains a wide variety of lesson ideas and reproducible pages designed for use with intermediate students. At its core,…

  18. SOCIAL INSECT PHEROMONES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Social insects include the social Hymenoptera (Formicidae, ants; Apidae, bees; Vespidae, wasps) and Isoptera (Termitidae, termites). Social interactions are required for effective food retrieval, brood and queen care, regulation of caste (sexuals/workers), recognition and exclusion of non-nestmates,...

  19. People and Insects.

    ERIC Educational Resources Information Center

    NatureScope, 1985

    1985-01-01

    Provides: (1) background information on how insects affect human lives, both positively and negatively, and on integrated pest management strategies; (2) student activities; and (3) materials (ready-to-copy games, puzzles, coloring pages, worksheets, and/or mazes). Each activity includes an objective, recommended age level(s), subject area(s),…

  20. Insect mass production technologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insects provide a very promising alternative for the future production of animal protein. Their nutritional value in conjunction with their food conversion efficiency and low water requirements, make them a more sustainable choice for the production of food and animal origin. However, to realize the...

  1. Recycled Insect Models

    ERIC Educational Resources Information Center

    Rule, Audrey C.; Meyer, Mary Ann

    2007-01-01

    This article presents an engaging activity in which high school students use a dichotomous key to guide the creation and classification of model insects from recycled plastic lids and containers. Besides teaching the use of a dichotomous key and the effect of evolutionary descent upon groupings of organisms, this activity focuses on an…

  2. Dispersal of forest insects

    NASA Technical Reports Server (NTRS)

    Mcmanus, M. L.

    1979-01-01

    Dispersal flights of selected species of forest insects which are associated with periodic outbreaks of pests that occur over large contiguous forested areas are discussed. Gypsy moths, spruce budworms, and forest tent caterpillars were studied for their massive migrations in forested areas. Results indicate that large dispersals into forested areas are due to the females, except in the case of the gypsy moth.

  3. Irradiating insect pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is a non-technical article focusing on phytosanitary uses of irradiation. In a series of interview questions, I present information on the scope of the invasive species problem and the contribution of international trade in agricultural products to the movement of invasive insects. This is foll...

  4. Corn Insect Pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Historically, the major corn insect pests have been corn rootworms (northern and western), European corn borer, and black cutworm. Bt-corn hybrids are effective against most of these pests. However, Bt-corn hybrids are not effective against corn leaf aphid, corn root aphid, sap beetles, corn rootwor...

  5. Colour constancy in insects.

    PubMed

    Chittka, Lars; Faruq, Samia; Skorupski, Peter; Werner, Annette

    2014-06-01

    Colour constancy is the perceptual phenomenon that the colour of an object appears largely unchanged, even if the spectral composition of the illuminating light changes. Colour constancy has been found in all insect species so far tested. Especially the pollinating insects offer a remarkable opportunity to study the ecological significance of colour constancy since they spend much of their adult lives identifying and choosing between colour targets (flowers) under continuously changing ambient lighting conditions. In bees, whose colour vision is best studied among the insects, the compensation provided by colour constancy is only partial and its efficiency depends on the area of colour space. There is no evidence for complete 'discounting' of the illuminant in bees, and the spectral composition of the light can itself be used as adaptive information. In patchy illumination, bees adjust their spatial foraging to minimise transitions between variously illuminated zones. Modelling allows the quantification of the adaptive benefits of various colour constancy mechanisms in the economy of nature. We also discuss the neural mechanisms and cognitive operations that might underpin colour constancy in insects. PMID:24647930

  6. Radar cross section of insects

    NASA Astrophysics Data System (ADS)

    Riley, J. R.

    1985-02-01

    X-band measurements of radar cross section as a function of the angle between insect body axis and the plane of polarization are presented. A finding of particular interest is that in larger insects, maximum cross section occurs when the E-vector is perpendicular to the body axis. A new range of measurements on small insects (aphids, and planthoppers) is also described, and a comprehensive summary of insect cross-section data at X-band is given.

  7. Detection of insects in grain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Detecting insects hidden inside kernels of grain is important to grain buyers because internal infestations can result in insect fragments in products made from the grain, or, if the grain is stored before use, the insect population can increase and damage the grain further. In a study in the Unite...

  8. Insect Ferritins: typical or atypical?

    PubMed Central

    Pham, Daphne Q. D.; Winzerling, Joy J.

    2010-01-01

    Insects transmit millions of cases of disease each year, and cost millions of dollars in agricultural losses. The control of insect-borne diseases is vital for numerous developing countries, and the management of agricultural insect pests is a very serious business for developed countries. Control methods should target insect-specific traits in order to avoid non-target effects, especially in mammals. Since insect cells have had a billion years of evolutionary divergence from those of vertebrates, they differ in many ways that might be promising for the insect control field—especially, in iron metabolism because current studies have indicated that significant differences exist between insect and mammalian systems. Insect iron metabolism differs from that of vertebrates in the following respects. Insect ferritins have a heavier mass than mammalian ferritins. Unlike their mammalian counterparts, the insect ferritin subunits are often glycosylated and are synthesized with a signal peptide. The crystal structure of insect ferritin also shows a tetrahedral symmetry consisting of 12 heavy chain and 12 light chain subunits in contrast to that of mammalian ferritin that exhibits an octahedral symmetry made of 24 heavy chain and 24 light chain subunits. Insect ferritins associate primarily with the vacuolar system and serve as iron transporters—quite the opposite of the mammalian ferritins, which are mainly cytoplasmic and serve as iron storage proteins. This review will discuss these differences. PMID:20230873

  9. Cellular localisation of the kinin B1R in the pancreas of streptozotocin-treated rat and the anti-diabetic effect of the antagonist SSR240612.

    PubMed

    Tidjane, Nejla; Gaboury, Louis; Couture, Réjean

    2016-04-01

    The mechanism by which kinin B1 receptor (B1R) contributes to type 1 diabetes is addressed by determining the impact of its inhibition on diabetes and on its pancreatic expression and cellular localisation on immunocompetent cells and primary sensory C-fibres. Rats were made diabetic with streptozotocin (STZ). On day 4, they were treated daily for 7 days with a B1R antagonist (SSR240612, 10 mg/kg) or its vehicle. The surviving β-cells were measured by immunostaining. The expression of B1R, iNOS, TNF-α, macrophages, TCD4+, CGRP and TRPV1 was measured by Western blotting, qRT-PCR and immunofluorescence. Macrophages and TCD4+ lymphocytes were absent in control, but distributed abundantly in the pancreas of STZ-diabetic rats. B1R was upregulated on these immune cells infiltrating the diabetic rat pancreas while it was not expressed on primary sensory C-fibres even if the expression of TRPV1 and CGRP was enhanced. SSR240612 prevented the infiltration of macrophages and TCD4+ lymphocytes and the upregulation of B1R, iNOS, TNF-α and TRPV1. SSR240612 corrected hyperglycaemia and hypoinsulinaemia by improving the Langerhans islets survival or regeneration. It is concluded that kinin B1R antagonism exerts anti-diabetic action by preventing the infiltration of immune cells in the pancreas and by preserving the integrity of Langerhans islets β-cells. PMID:26841446

  10. Evidence for the involvement of a plasma kallikrein-kinin system in the immediate hypotension produced by endotoxin in anaesthetized rats.

    PubMed Central

    Katori, M.; Majima, M.; Odoi-Adome, R.; Sunahara, N.; Uchida, Y.

    1989-01-01

    1. In vitro incubation of normal rat plasma with endotoxin from E. coli (3-10 mg ml-1) in the incubation mixture) caused a dose-dependent increase in levels of free kinin and plasma kallikrein in the presence of o-phenanthroline, together with a mirror-image, dose-dependent decrease in the residual levels of the precursors, plasma prekallikrein and high-molecular-weight kininogen. Low-molecular-weight kininogen levels were not modified. 2. Intravenous injection of endotoxin (3-30 mg kg-1) into the femoral vein of anaesthetized rats resulted in dose-dependent hypotension. In blood collected up to 15 min after injection, the levels of prekallikrein and high-molecular-weight kininogen in plasma were decreased while levels of the active forms, plasma kallikrein and free kinin, showed a transient increase in the blood 1 min after administration of endotoxin. 3. A degradation product of bradykinin, des-Phe8-Arg9-bradykinin, as measured by a newly developed enzyme immunoassay, was detectable up to 5 min after administration of endotoxin. 4. Intravenous infusion of soybean trypsin inhibitor inhibited both the formation of bradykinin and des-Phe8-Arg9-bradykinin and the initial hypotension. 5. It can be concluded from our results that plasma prekallikrein is activated in the blood immediately after administration of endotoxin to rats and that bradykinin is a major cause of the immediate hypotension. PMID:2692754

  11. Insect maintenance and transmission.

    PubMed

    Kingdom, Heather

    2013-01-01

    Phytoplasmas are plant pathogens of huge economic importance due to responsibility for crop yield losses worldwide. Institutions around the world are trying to understand and control this yield loss at a time when food security is high on government agendas. In order to fully understand the mechanisms of phytoplasma infection and spread, more insect vector and phytoplasma colonies will need to be established for research worldwide. Rearing and study of these colonies is essential in the research and development of phytoplasma control measures. This chapter highlights general materials and methods for raising insect vector colonies and maintenance of phytoplasmas. Specific methods of rearing the maize leafhopper and maize bushy stunt phytoplasma and the aster leafhopper and aster yellows phytoplasma strain witches' broom are also included. PMID:22987405

  12. On quantifying insect movements

    SciTech Connect

    Wiens, J.A.; Crist, T.O. ); Milne, B.T. )

    1993-08-01

    We elaborate on methods described by Turchin, Odendaal Rausher for quantifying insect movement pathways. We note the need to scale measurement resolution to the study insects and the questions being asked, and we discuss the use of surveying instrumentation for recording sequential positions of individuals on pathways. We itemize several measures that may be used to characterize movement pathways and illustrate these by comparisons among several Eleodes beetles occurring in shortgrass steppe. The fractal dimension of pathways may provide insights not available from absolute measures of pathway configuration. Finally, we describe a renormalization procedure that may be used to remove sequential interdependence among locations of moving individuals while preserving the basic attributes of the pathway.

  13. Undergraduates' mental models about insect anatomy and insect life cycles

    NASA Astrophysics Data System (ADS)

    Diaz, Arlene Edith

    Educational studies focused on students' alternative conceptions have shown the importance of developing strategies to correct understanding. Identifying and comprehending student mental models are important since they may reflect alternate conceptions about scientific concepts. Mental models have been identified in various science education studies, but little is known about mental models undergraduates hold about insects. This research is significant because it identified mental models undergraduates have about insect anatomy and insect life cycles, exposed students to cognitive conflict by having them complete an online insect tutorial, and analyzed the effectiveness of this insect tutorial in correcting student understanding. An insect assessment was developed and administered pre- and post-instruction to probe students' mental models about insects. Different numbers of undergraduate students participated in different parts of the assessment; 276, 249, 166, and 58 students participated in the listing, drawing. definition, and life cycle parts of the assessment, respectively. The tutorial contained a variety of manipulated insect and non-insect images that challenged the students' understanding and generated cognitive conflict. This intervention guided students in replacing alternate conceptions with correct understanding. It was hypothesized that the tutorial would have a positive impact on student learning about insects. The results suggest that the tutorial had a positive impact on learning.

  14. [Protection against insects].

    PubMed

    Rudin, W

    2005-11-01

    Successful protection against haematophagous insects and ticks, especially in areas where transmission of diseases occurs, requires a consistent application of a combination of appropriate measures. However, this can never substitute a chemoprophylaxis. Which measures have to be used depends on the circumstances under which they have to work. Indoor, physical means such as mosquito-screens on doors and windows, air-conditioners, and bed nets can be used to keep the insects away. These measures can be supplemented or supported by insecticides used as knock-down sprays, by electrical evaporation or for the treatment of screens and bed nets. In the field, if it is not possible to avoid mosquito-areas during phases of activity, appropriate clothing and repellents must provide the protection. Bright, wide pants and shirts of dense weaving covering as much skin as bearable should be preferred. Repellents are sprays, lotions, milks or creams which are evenly applied to the skin to prevent insects from biting. They contain synthetic or natural active substances of substantially varying effectiveness. The gold standard since about 60 years is diethylbenzamine (DEET). There are a few other active substances with a lower risk of side effects, however, combined with a lower effectiveness mainly on people with a high attractiveness for mosquitoes. Products containing an extract of Eucalyptus citriodora provide the best protection amongst those with natural active substances. Wearing bracelets or necklaces treated with repellents, acoustic devices (buzzers), electrocuters, topical or systemic Vitamin B1 or eating garlic are useless measures to prevent insects from biting. PMID:16350532

  15. Interrogating an insect society

    PubMed Central

    Gadagkar, Raghavendra

    2009-01-01

    Insect societies such as those of ants, bees, and wasps consist of 1 or a small number of fertile queens and a large number of sterile or nearly sterile workers. While the queens engage in laying eggs, workers perform all other tasks such as nest building, acquisition and processing of food, and brood care. How do such societies function in a coordinated and efficient manner? What are the rules that individuals follow? How are these rules made and enforced? These questions are of obvious interest to us as fellow social animals but how do we interrogate an insect society and seek answers to these questions? In this article I will describe my research that was designed to seek answers from an insect society to a series of questions of obvious interest to us. I have chosen the Indian paper wasp Ropalidia marginata for this purpose, a species that is abundantly distributed in peninsular India and serves as an excellent model system. An important feature of this species is that queens and workers are morphologically identical and physiologically nearly so. How then does an individual become a queen? How does the queen suppress worker reproduction? How does the queen regulate the nonreproductive activities of the workers? What is the function of aggression shown by different individuals? How and when is the queen's heir decided? I will show how such questions can indeed be investigated and will emphasize the need for a whole range of different techniques of observation and experimentation. PMID:19487678

  16. Fatigue of insect cuticle.

    PubMed

    Dirks, Jan-Henning; Parle, Eoin; Taylor, David

    2013-05-15

    Many parts of the insect exoskeleton experience repeated cyclic loading. Although the cuticle of insects and other arthropods is the second most common natural composite material in the world, so far nothing is known about its fatigue properties, despite the fact that fatigue undoubtedly limits the durability of body parts in vivo. For the first time, we here present experimental fatigue data of insect cuticle. Using force-controlled cyclic loading, we determined the number of cycles to failure for hind legs (tibiae) and hind wings of the locust Schistocerca gregaria, as a function of the applied cyclic stress. Our results show that, although both are made from cuticle, these two body parts behave very differently. Wing samples showed a large fatigue range, failing after 100,000 cycles when we applied 46% of the stress needed for instantaneous failure [the ultimate tensile strength (UTS)]. Legs, in contrast, were able to sustain a stress of 76% of the UTS for the same number of cycles to failure. This can be explained by the difference in the composition and structure of the material, two factors that, amongst others, also affect the well-known behaviour of engineering composites. Final failure of the tibiae occurred via one of two different failure modes--propagation in tension or buckling in compression--indicating that the tibia is 'optimized' by evolution to resist both failure modes equally. These results are further discussed in relation to the evolution and normal use of these two body parts. PMID:23393276

  17. Escape behaviors in insects.

    PubMed

    Card, Gwyneth M

    2012-04-01

    Escape behaviors are, by necessity, fast and robust, making them excellent systems with which to study the neural basis of behavior. This is especially true in insects, which have comparatively tractable nervous systems and members who are amenable to manipulation with genetic tools. Recent technical developments in high-speed video reveal that, despite their short duration, insect escape behaviors are more complex than previously appreciated. For example, before initiating an escape jump, a fly performs sophisticated posture and stimulus-dependent preparatory leg movements that enable it to jump away from a looming threat. This newfound flexibility raises the question of how the nervous system generates a behavior that is both rapid and flexible. Recordings from the cricket nervous system suggest that synchrony between the activity of specific interneuron pairs may provide a rapid cue for the cricket to detect the direction of an approaching predator and thus which direction it should run. Technical advances make possible wireless recording from neurons while locusts escape from a looming threat, enabling, for the first time, a direct correlation between the activity of multiple neurons and the time-course of an insect escape behavior. PMID:22226514

  18. Edible insects are the future?

    PubMed

    van Huis, Arnold

    2016-08-01

    The global increase in demand for meat and the limited land area available prompt the search for alternative protein sources. Also the sustainability of meat production has been questioned. Edible insects as an alternative protein source for human food and animal feed are interesting in terms of low greenhouse gas emissions, high feed conversion efficiency, low land use, and their ability to transform low value organic side streams into high value protein products. More than 2000 insect species are eaten mainly in tropical regions. The role of edible insects in the livelihoods and nutrition of people in tropical countries is discussed, but this food source is threatened. In the Western world, there is an increasing interest in edible insects, and examples are given. Insects as feed, in particular as aquafeed, have a large potential. Edible insects have about the same protein content as conventional meat and more PUFA. They may also have some beneficial health effects. Edible insects need to be processed and turned into palatable dishes. Food safety may be affected by toxicity of insects, contamination with pathogens, spoilage during conservation and allergies. Consumer attitude is a major issue in the Western world and a number of strategies are proposed to encourage insect consumption. We discuss research pathways to make insects a viable sector in food and agriculture: an appropriate disciplinary focus, quantifying its importance, comparing its nutritional value to conventional protein sources, environmental benefits, safeguarding food safety, optimising farming, consumer acceptance and gastronomy. PMID:26908196

  19. Cigarette smoke-induced kinin B1 receptor promotes NADPH oxidase activity in cultured human alveolar epithelial cells.

    PubMed

    Talbot, Sébastien; Lin, James Chi-Jen; Lahjouji, Karim; Roy, Jean-Philippe; Sénécal, Jacques; Morin, André; Couture, Réjean

    2011-07-01

    Pulmonary inflammation is an important pathological feature of tobacco smoke-related lung diseases. Kinin B1 receptor (B1R) is up-regulated in the rat trachea chronically exposed to cigarette-smoke. This study aimed at determining (1) whether exposure to total particulate matter of the cigarette smoke (TPM) can induce B1R in human alveolar epithelial A549 cells, (2) the mechanism of B1R induction, (3) the functionality of de novo synthesized B1R, and (4) the role of B1R in TPM-induced increase of superoxide anion (O₂(●⁻)) level. Results show that A549 cells exposed to 10 μg/ml TPM increased O₂(●⁻) level along with B1R (protein and mRNA) and IL-1β mRNA. In contrast, B2R and TNF-α mRNA were not affected by TPM. The increasing effect of TPM on O₂(●⁻) level was not significantly affected by the B1R antagonist SSR240612. TPM-increased B1R mRNA was prevented by co-treatments with N-acetyl-l-cysteine (potent antioxidant), diphenyleneiodonium (NADPH oxidase inhibitor), IL-1Ra (interleukin-1R antagonist) and SN-50 (specific inhibitor of NF-kB activation) but not by pentoxifylline (TNF-α release inhibitor), indomethacin and niflumic acid (COX-1 and -2 inhibitors). Stimulation of B1R with a selective agonist (des-Arg⁹-BK, 10 μM; 30 min) increased O₂(●⁻)production which was prevented by apocynin and diphenyleneiodonium (NADPH oxidase inhibitors). Data suggest that the increased expression of B1R by TPM in A549 cells is mediated by oxidative stress, IL-1β and NF-kB but not by cyclooxygenases or TNF-α. The amplification of O₂(●⁻) levels via the activation of B1R-NADPH oxidase may exacerbate pulmonary inflammation and contribute to the chronicity of tobacco smoke-related lung diseases. PMID:21600945

  20. Insect bite prevention.

    PubMed

    Moore, Sarah J; Mordue Luntz, Anne Jennifer; Logan, James G

    2012-09-01

    Protection from the bites of arthropod (insect and acarine) vectors of disease is the first line of defense against disease transmission and should be advised in all cases when traveling abroad. Details are described of the main approaches for the prevention of bites, including topical or skin repellents, impregnated clothing, bed nets, and spatial or aerial repellents and aerosols. The bionomics of the main arthropod vectors of disease are described along with photographic plates and tabulated advice to give the traveler. An in-depth treatment of the different protection methodologies provides an up-to-date overview of the technologies involved. PMID:22963776

  1. Aircraft anti-insect system

    NASA Technical Reports Server (NTRS)

    Spiro, Clifford Lawrence (Inventor); Fric, Thomas Frank (Inventor); Leon, Ross Michael (Inventor)

    1997-01-01

    Insect debris is removed from or prevented from adhering to insect impingement areas of an aircraft, particularly on an inlet cowl of an engine, by heating the area to 180.degree.-500.degree. C. An apparatus comprising a means to bring hot air from the aircraft engine to a plenum contiguous to the insect impingement area provides for the heating of the insect impingement areas to the required temperatures. The plenum can include at least one tube with a plurality of holes contained in a cavity within the inlet cowl. It can also include an envelope with a plurality of holes on its surface contained in a cavity within the inlet cowl.

  2. 1977 Kansas Field Crop Insect Control Recommendations.

    ERIC Educational Resources Information Center

    Brooks, Leroy; Gates, Dell E.

    This publication is prepared to aid producers in selecting methods of insect population management that have proved effective under Kansas conditions. Topics covered include insect control on alfalfa, soil insects attacking corn, insects attacking above-ground parts of corn, and sorghum, wheat, and soybean insect control. The insecticides…

  3. 7 CFR 51.2122 - Insect injury.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Insect injury. 51.2122 Section 51.2122 Agriculture... Standards for Grades of Shelled Almonds Definitions § 51.2122 Insect injury. Insect injury means that the insect, web, or frass is present or there is definite evidence of insect feeding....

  4. 7 CFR 51.2290 - Insect injury.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Insect injury. 51.2290 Section 51.2290 Agriculture... Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2290 Insect injury. Insect injury means that the insect, web, frass or other evidence of insects is present on the portion of kernel....

  5. 7 CFR 51.2008 - Insect injury.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Insect injury. 51.2008 Section 51.2008 Agriculture....2008 Insect injury. Insect injury means that the insect, frass or web is present inside the nut or the kernel shows definite evidence of insect feeding. Metric Conversion Table...

  6. 7 CFR 51.2290 - Insect injury.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Insect injury. 51.2290 Section 51.2290 Agriculture... Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2290 Insect injury. Insect injury means that the insect, web, frass or other evidence of insects is present on the portion of kernel....

  7. 7 CFR 51.2290 - Insect injury.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Insect injury. 51.2290 Section 51.2290 Agriculture... Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2290 Insect injury. Insect injury means that the insect, web, frass or other evidence of insects is present on the portion of kernel....

  8. 7 CFR 51.2122 - Insect injury.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Insect injury. 51.2122 Section 51.2122 Agriculture... Standards for Grades of Shelled Almonds Definitions § 51.2122 Insect injury. Insect injury means that the insect, web, or frass is present or there is definite evidence of insect feeding....

  9. 7 CFR 51.2008 - Insect injury.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Insect injury. 51.2008 Section 51.2008 Agriculture....2008 Insect injury. Insect injury means that the insect, frass or web is present inside the nut or the kernel shows definite evidence of insect feeding. Metric Conversion Table...

  10. 7 CFR 51.2122 - Insect injury.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Insect injury. 51.2122 Section 51.2122 Agriculture... Standards for Grades of Shelled Almonds Definitions § 51.2122 Insect injury. Insect injury means that the insect, web, or frass is present or there is definite evidence of insect feeding....

  11. Hydrodynamics of insect spermatozoa

    NASA Astrophysics Data System (ADS)

    Pak, On Shun; Lauga, Eric

    2010-11-01

    Microorganism motility plays important roles in many biological processes including reproduction. Many microorganisms propel themselves by propagating traveling waves along their flagella. Depending on the species, propagation of planar waves (e.g. Ceratium) and helical waves (e.g. Trichomonas) were observed in eukaryotic flagellar motion, and hydrodynamic models for both were proposed in the past. However, the motility of insect spermatozoa remains largely unexplored. An interesting morphological feature of such cells, first observed in Tenebrio molitor and Bacillus rossius, is the double helical deformation pattern along the flagella, which is characterized by the presence of two superimposed helical flagellar waves (one with a large amplitude and low frequency, and the other with a small amplitude and high frequency). Here we present the first hydrodynamic investigation of the locomotion of insect spermatozoa. The swimming kinematics, trajectories and hydrodynamic efficiency of the swimmer are computed based on the prescribed double helical deformation pattern. We then compare our theoretical predictions with experimental measurements, and explore the dependence of the swimming performance on the geometric and dynamical parameters.

  12. Environmental RNAi in herbivorous insects

    PubMed Central

    Ivashuta, Sergey; Zhang, Yuanji; Wiggins, B. Elizabeth; Ramaseshadri, Partha; Segers, Gerrit C.; Johnson, Steven; Meyer, Steve E.; Kerstetter, Randy A.; McNulty, Brian C.; Bolognesi, Renata; Heck, Gregory R.

    2015-01-01

    Environmental RNAi (eRNAi) is a sequence-specific regulation of endogenous gene expression in a receptive organism by exogenous double-stranded RNA (dsRNA). Although demonstrated under artificial dietary conditions and via transgenic plant presentations in several herbivorous insects, the magnitude and consequence of exogenous dsRNA uptake and the role of eRNAi remains unknown under natural insect living conditions. Our analysis of coleopteran insects sensitive to eRNAi fed on wild-type plants revealed uptake of plant endogenous long dsRNAs, but not small RNAs. Subsequently, the dsRNAs were processed into 21 nt siRNAs by insects and accumulated in high quantities in insect cells. No accumulation of host plant-derived siRNAs was observed in lepidopteran larvae that are recalcitrant to eRNAi. Stability of ingested dsRNA in coleopteran larval gut followed by uptake and transport from the gut to distal tissues appeared to be enabling factors for eRNAi. Although a relatively large number of distinct coleopteran insect-processed plant-derived siRNAs had sequence complementarity to insect transcripts, the vast majority of the siRNAs were present in relatively low abundance, and RNA-seq analysis did not detect a significant effect of plant-derived siRNAs on insect transcriptome. In summary, we observed a broad genome-wide uptake of plant endogenous dsRNA and subsequent processing of ingested dsRNA into 21 nt siRNAs in eRNAi-sensitive insects under natural feeding conditions. In addition to dsRNA stability in gut lumen and uptake, dosage of siRNAs targeting a given insect transcript is likely an important factor in order to achieve measurable eRNAi-based regulation in eRNAi-competent insects that lack an apparent silencing amplification mechanism. PMID:25802407

  13. Kinin B2 receptor regulates chemokines CCL2 and CCL5 expression and modulates leukocyte recruitment and pathology in experimental autoimmune encephalomyelitis (EAE) in mice

    PubMed Central

    Dos Santos, Adriana C; Roffê, Ester; Arantes, Rosa ME; Juliano, Luiz; Pesquero, Jorge L; Pesquero, João B; Bader, Michael; Teixeira, Mauro M; Carvalho-Tavares, Juliana

    2008-01-01

    Background Kinins are important mediators of inflammation and act through stimulation of two receptor subtypes, B1 and B2. Leukocyte infiltration contributes to the pathogenesis of autoimmune inflammation in the central nervous system (CNS), occurring not only in multiple sclerosis (MS) but also in experimental autoimmune encephalomyelitis (EAE). We have previously shown that the chemokines CCL2 and CCL5 play an important role in the adhesion of leukocytes to the brain microcirculation in EAE. The aim of the present study was to evaluate the relevance of B2 receptors to leukocyte-endothelium interactions in the cerebral microcirculation, and its participation in CNS inflammation in the experimental model of myelin-oligodendrocyte-glycoprotein (MOG)35–55-induced EAE in mice. Methods In order to evaluate the role of B2 receptor in the cerebral microvasculature we used wild-type (WT) and kinin B2 receptor knockout (B2-/-) mice subjected to MOG35–55-induced EAE. Intravital microscopy was used to investigate leukocyte recruitment on pial matter vessels in B2-/- and WT EAE mice. Histological documentation of inflammatory infiltrates in brain and spinal cords was correlated with intravital findings. The expression of CCL5 and CCL2 in cerebral tissue was assessed by ELISA. Results Clinical parameters of disease were reduced in B2-/- mice in comparison to wild type EAE mice. At day 14 after EAE induction, there was a significant decrease in the number of adherent leukocytes, a reduction of cerebral CCL5 and CCL2 expressions, and smaller inflammatory and degenerative changes in B2-/- mice when compared to WT. Conclusion Our results suggest that B2 receptors have two major effects in the control of EAE severity: (i) B2 regulates the expression of chemokines, including CCL2 and CCL5, and (ii) B2 modulates leukocyte recruitment and inflammatory lesions in the CNS. PMID:18986535

  14. Plant Defense against Insect Herbivores

    PubMed Central

    Fürstenberg-Hägg, Joel; Zagrobelny, Mika; Bak, Søren

    2013-01-01

    Plants have been interacting with insects for several hundred million years, leading to complex defense approaches against various insect feeding strategies. Some defenses are constitutive while others are induced, although the insecticidal defense compound or protein classes are often similar. Insect herbivory induce several internal signals from the wounded tissues, including calcium ion fluxes, phosphorylation cascades and systemic- and jasmonate signaling. These are perceived in undamaged tissues, which thereafter reinforce their defense by producing different, mostly low molecular weight, defense compounds. These bioactive specialized plant defense compounds may repel or intoxicate insects, while defense proteins often interfere with their digestion. Volatiles are released upon herbivory to repel herbivores, attract predators or for communication between leaves or plants, and to induce defense responses. Plants also apply morphological features like waxes, trichomes and latices to make the feeding more difficult for the insects. Extrafloral nectar, food bodies and nesting or refuge sites are produced to accommodate and feed the predators of the herbivores. Meanwhile, herbivorous insects have adapted to resist plant defenses, and in some cases even sequester the compounds and reuse them in their own defense. Both plant defense and insect adaptation involve metabolic costs, so most plant-insect interactions reach a stand-off, where both host and herbivore survive although their development is suboptimal. PMID:23681010

  15. Polarization Imaging and Insect Vision

    ERIC Educational Resources Information Center

    Green, Adam S.; Ohmann, Paul R.; Leininger, Nick E.; Kavanaugh, James A.

    2010-01-01

    For several years we have included discussions about insect vision in the optics units of our introductory physics courses. This topic is a natural extension of demonstrations involving Brewster's reflection and Rayleigh scattering of polarized light because many insects heavily rely on optical polarization for navigation and communication.…

  16. Reader Survey for INSECT ALERTS.

    ERIC Educational Resources Information Center

    Miller, Mason E.; Sauer, Richard J.

    To determine what might be done to improve "Insect Alerts," which is a newsletter that carries "information on insect biology, abundance, activity and interpretation of control need," put out through the Michigan Cooperative Extension Service 26 weeks a year, a survey was conducted. A mail questionnaire was sent to all 120 county extension…

  17. RNAI: Future in insect management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    RNA interference is a post-transcriptional, gene regulation mechanism found in virtually all plants and animals including insects. The demonstration of RNAi in insects and its successful use as a tool in the study of functional genomics opened the door to the development of a variety of novel, envir...

  18. Chickpea Ascochyta blight and insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Early symptoms of Acochyta blight and insect damages were detected in the Paliuse region.This article informs chickpea scientists and growers about current disease and insect pest problems in the Palouse region. Ascochyta blight appeared in many chickpea fields and was severe in some fields. Insec...

  19. A Template for Insect Cryopreservation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article is intended to update the reader on the progress made on insect embryo cryopreservation in the past 20 years and gives information for developing a protocol for cryopreserving insects by using a 2001 study as a template. The study used for the template is the cryopreservation of the Old...

  20. Eicosanoids mediate insect hemocyte migration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hemocyte chemotaxis toward infection and wound sites is an essential component of insect defense reactions, although the biochemical signal mechanisms responsible for mediating chemotaxis in insect cells are not well understood. Here we report on the outcomes of experiments designed to test the hyp...

  1. Insect Immunity to Entomopathogenic Fungi.

    PubMed

    Lu, H-L; St Leger, R J

    2016-01-01

    The study of infection and immunity in insects has achieved considerable prominence with the appreciation that their host defense mechanisms share many fundamental characteristics with the innate immune system of vertebrates. Studies on the highly tractable model organism Drosophila in particular have led to a detailed understanding of conserved innate immunity networks, such as Toll. However, most of these studies have used opportunistic human pathogens and may not have revealed specialized immune strategies that have arisen through evolutionary arms races with natural insect pathogens. Fungi are the commonest natural insect pathogens, and in this review, we focus on studies using Metarhizium and Beauveria spp. that have addressed immune system function and pathogen virulence via behavioral avoidance, the use of physical barriers, and the activation of local and systemic immune responses. In particular, we highlight studies on the evolutionary genetics of insect immunity and discuss insect-pathogen coevolution. PMID:27131327

  2. Population fluctuation in phytophagous insects

    SciTech Connect

    Redfearn, A.; Pimm, S.L. )

    1994-06-01

    We examined how community interactions affect year-to-year population variability in three groups of phytophagous insects: British aphids and moths, and Canadian moths. We first examined how the number of host plant species on which a given phytophagous insect species feeds affects its population variability. Specialist insect species showed a weak tendency to be more variable than generalist species. We then examined how the number of species of parasitoids from which a given phytophagous insects species suffers affects its population variability. Species that are host to few parasitoid species showed a weak tendency to be more variable than species with many parsitoid species. These relationships also depend on other aspects of the life histories of the phytophagous insect species.

  3. In vitro and in vivo activity of analogues of the kinin B2 receptor antagonist MEN1 1270.

    PubMed

    Meini, S; Lecci, A; Carini, F; Tramontana, M; Giuliani, S; Maggi, C A; Ricci, R; Fabbri, G; Anichini, B; Harmat, N; Rizzi, A; Camarda, V; Regoli, D; Quartara, L

    2002-04-01

    In this study, we describe the in vitro and in vivo activities of a series of cyclic peptide analogues of the selective kinin B2 receptor antagonist MEN11270 on Chinese hamster ovary cells expressing the human B2 receptor (hB2R), the human isolated umbilical vein (hUV), the isolated guinea pig ileum (gpI), and bradykinin (BK) induced bronchoconstriction (BC) and hypotension in anaesthetized guinea pigs. Substitutions in the backbone of MEN1 1270 (H-DArg-Arg-Pro-Hyp-Gly-Thi-c(Dab-DTic-Oic-Arg)c(7gamma-10alpha)) aimed to increase the potency in inhibiting bronchospasm versus hypotension following the topical (intratracheal (i.t.)) or systemic (intravenous (i.v.)) application of these antagonists. A series of analogues were left unprotected from N-terminal cleavage by aminopeptidases (MEN12739, MEN13052, MEN13346, and MEN13371): these compounds maintained sizeable affinities for the hB2R (pKi = 9.4, 9.6, 9.7, and 8.6, respectively) and antagonist activities toward BK in the hUV (pA2 = 7.9, 8.3, 8.2, and 7.5) and gpI assays (pK(B) = 7.4, 7.8, 7.9, and 7.9), but the inhibition of BK-induced BC and hypotension in vivo was negligible following either i.v. or i.t. administration. Two analogues (MEN12388 and MEN13405) could be potential substrates of angiotensin-converting enzyme: these have good activity in the hB2R (pKi = 9.5 and 8.9, respectively), hUV (pA2 = 8.2 for MEN12388), and gpI assays (pK(B) = 8.4 and 8.0) but an in vivo activity 10- to 30-fold lower than the parent compound MEN1 1270 (pKi = 9.4, pA2 = 8.1, pKB = 8.3) when given by either the i.v. or the i.t. route. Other analogues were functionalized with a quaternary ammonium Lys derivative (MEN13031, MEN12374, and the previously mentioned MEN13052) or with an ethyl group on Arg (MEN13655 and the previously mentioned MEN13346 and MEN13405) in order to hinder or facilitate local absorption. MEN13346 and MEN13031 (pKi = 9.7and 9.5, pA2 = 8.2 and 7.9, pKB = 7.9 and 8.5, respectively) were 10- to 30-fold less

  4. Activation of TRPV1 by capsaicin induces functional Kinin B1 receptor in rat spinal cord microglia

    PubMed Central

    2012-01-01

    Background The kinin B1 receptor (B1R) is upregulated by pro-inflammatory cytokines and oxydative stress, which are enhanced by transient receptor potential vanilloid subtype 1 (TRPV1) activation. To examine the link between TRPV1 and B1R in inflammatory pain, this study aimed to determine the ability of TRPV1 to regulate microglial B1R expression in the spinal cord dorsal horn, and the underlying mechanism. Methods B1R expression (mRNA, protein and binding sites) was measured in cervical, thoracic and lumbar spinal cord in response to TRPV1 activation by systemic capsaicin (1-50 mg/kg, s.c) in rats pre-treated with TRPV1 antagonists (capsazepine or SB-366791), the antioxidant N-acetyl-L-cysteine (NAC), or vehicle. B1R function was assessed using a tail-flick test after intrathecal (i.t.) injection of a selective B1R agonist (des-Arg9-BK), and its microglial localization was investigated by confocal microscopy with the selective fluorescent B1R agonist, [Nα-bodipy]-des-Arg9-BK. The effect of i.t. capsaicin (1 μg/site) was also investigated. Results Capsaicin (10 to 50 mg/kg, s.c.) enhanced time-dependently (0-24h) B1R mRNA levels in the lumbar spinal cord; this effect was prevented by capsazepine (10 mg/kg, i.p.; 10 μg/site, i.t.) and SB-366791 (1 mg/kg, i.p.; 30 μg/site, i.t.). Increases of B1R mRNA were correlated with IL-1β mRNA levels, and they were significantly less in cervical and thoracic spinal cord. Intrathecal capsaicin (1 μg/site) also enhanced B1R mRNA in lumbar spinal cord. NAC (1 g/kg/d × 7 days) prevented B1R up-regulation, superoxide anion production and NF-kB activation induced by capsaicin (15 mg/kg). Des-Arg9-BK (9.6 nmol/site, i.t.) decreased by 25-30% the nociceptive threshold at 1 min post-injection in capsaicin-treated rats (10-50 mg/kg) while it was without effect in control rats. Des-Arg9-BK-induced thermal hyperalgesia was blocked by capsazepine, SB-366791 and by antagonists/inhibitors of B1R (SSR240612, 10 mg/kg, p.o.), glutamate

  5. The aerodynamics of insect flight.

    PubMed

    Sane, Sanjay P

    2003-12-01

    The flight of insects has fascinated physicists and biologists for more than a century. Yet, until recently, researchers were unable to rigorously quantify the complex wing motions of flapping insects or measure the forces and flows around their wings. However, recent developments in high-speed videography and tools for computational and mechanical modeling have allowed researchers to make rapid progress in advancing our understanding of insect flight. These mechanical and computational fluid dynamic models, combined with modern flow visualization techniques, have revealed that the fluid dynamic phenomena underlying flapping flight are different from those of non-flapping, 2-D wings on which most previous models were based. In particular, even at high angles of attack, a prominent leading edge vortex remains stably attached on the insect wing and does not shed into an unsteady wake, as would be expected from non-flapping 2-D wings. Its presence greatly enhances the forces generated by the wing, thus enabling insects to hover or maneuver. In addition, flight forces are further enhanced by other mechanisms acting during changes in angle of attack, especially at stroke reversal, the mutual interaction of the two wings at dorsal stroke reversal or wing-wake interactions following stroke reversal. This progress has enabled the development of simple analytical and empirical models that allow us to calculate the instantaneous forces on flapping insect wings more accurately than was previously possible. It also promises to foster new and exciting multi-disciplinary collaborations between physicists who seek to explain the phenomenology, biologists who seek to understand its relevance to insect physiology and evolution, and engineers who are inspired to build micro-robotic insects using these principles. This review covers the basic physical principles underlying flapping flight in insects, results of recent experiments concerning the aerodynamics of insect flight, as well

  6. Kinin danger signals proteolytically released by gingipain induce fimbriae-specific IFN-γ and IL-17-producing T cells in mice infected intramucosally with Porphyromonas gingivalis”

    PubMed Central

    Monteiro, Ana Carolina; Scovino, Aline; Raposo, Susane; Gaze, Vinicius Mussa; Cruz, Catia; Svensjö, Erik; Narciso, Marcelo Sampaio; Colombo, Ana Paula; Pesquero, João B.; Feres-Filho, Eduardo; Nguyen, Ky-Anh; Sroka, Aneta; Potempa, Jan; Scharfstein, Julio

    2009-01-01

    Porphyromonas gingivalis, a gram-negative bacterium that causes periodontitis, activates the kinin system via the cysteine protease R-gingipain. Using a model of buccal infection based on P. gingivalis inoculation in the anterior mandibular vestibule, here we studied whether kinins released by gingipain may link mucosal inflammation to T cell-dependent immunity through the activation of bradykinin B2 receptors (B2R). Our data show that P. gingivalis W83 (WT), but not gingipain deficient mutant or WT bacteria pretreated with gingipain inhibitors, elicited buccal edema and gingivitis in Balb/C or C57BL/6 mice. Studies in TLR2−/−, B2R−/− and neutrophil-depleted C57Bl/6 mice revealed that P. gingivalis induced edema through the sequential activation of TLR2/neutrophils, with the initial plasma leakage being amplified by gingipain-dependent release of vasoactive kinins from plasma-borne kininogens. We then used fimbriae (Fim) Ag as a read-out to verify if activation of the TLR2>PMN>B2R axis at early-stages of mucosal infection had impact on adaptive immunity. Analyzes of T cell recall responses indicated that gingipain drives B2R-dependent generation of IFN-γ-producing Fim T cells in submandibular draining LNs of Balb/C and C57BL/6 mice while IL-17-producing Fim T cells were generated only in Balb/C mice. In summary, our studies suggest that two virulence factors, LPS (an atypical TLR2 ligand) and gingipain, forges a trans-cellular cross-talk between TLR2/B2R, thus forming an innate axis that guides the development of Fim-specific T cells in mice challenged intrabuccally by P. gingivalis. Ongoing research may clarify if kinin-driven modulation of T cell responses may also influence the severity of chronic periodontitis. PMID:19687097

  7. Peripheral olfactory signaling in insects

    PubMed Central

    Suh, Eunho; Bohbot, Jonathan; Zwiebel, Laurence J.

    2014-01-01

    Olfactory signaling is a crucial component in the life history of insects. The development of precise and parallel mechanisms to analyze the tremendous amount of chemical information from the environment and other sources has been essential to their evolutionary success. Considerable progress has been made in the study of insect olfaction fueled by bioinformatics- based utilization of genomics along with rapid advances in functional analyses. Here we review recent progress in our rapidly emerging understanding of insect peripheral sensory reception and signal transduction. These studies reveal that the nearly unlimited chemical space insects encounter is covered by distinct chemosensory receptor repertoires that are generally derived by species-specific, rapid gene gain and loss, reflecting the evolutionary consequences of adaptation to meet their specific biological needs. While diverse molecular mechanisms have been put forth, often in the context of controversial models, the characterization of the ubiquitous, highly conserved and insect-specific Orco odorant receptor co-receptor has opened the door to the design and development of novel insect control methods to target agricultural pests, disease vectors and even nuisance insects. PMID:25584200

  8. Entomopathogenic nematodes and insect management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Entomopathogenic nematodes (genera Heterorhabditis, Steinernema, and Neosteinernema) are used as bioinsecticides. The nematodes are ubiquitous and have been isolated in soil of every continent except Antarctica. The nematodes kill insects through a mutualism with a bacterium (Photorhabdus spp. or ...

  9. Insect symbionts in food webs

    PubMed Central

    Henry, Lee M.

    2016-01-01

    Recent research has shown that the bacterial endosymbionts of insects are abundant and diverse, and that they have numerous different effects on their hosts' biology. Here we explore how insect endosymbionts might affect the structure and dynamics of insect communities. Using the obligate and facultative symbionts of aphids as an example, we find that there are multiple ways that symbiont presence might affect food web structure. Many symbionts are now known to help their hosts escape or resist natural enemy attack, and others can allow their hosts to withstand abiotic stress or affect host plant use. In addition to the direct effect of symbionts on aphid phenotypes there may be indirect effects mediated through trophic and non-trophic community interactions. We believe that by using data from barcoding studies to identify bacterial symbionts, this extra, microbial dimension to insect food webs can be better elucidated. This article is part of the themed issue ‘From DNA barcodes to biomes’. PMID:27481779

  10. Insect symbionts in food webs.

    PubMed

    McLean, Ailsa H C; Parker, Benjamin J; Hrček, Jan; Henry, Lee M; Godfray, H Charles J

    2016-09-01

    Recent research has shown that the bacterial endosymbionts of insects are abundant and diverse, and that they have numerous different effects on their hosts' biology. Here we explore how insect endosymbionts might affect the structure and dynamics of insect communities. Using the obligate and facultative symbionts of aphids as an example, we find that there are multiple ways that symbiont presence might affect food web structure. Many symbionts are now known to help their hosts escape or resist natural enemy attack, and others can allow their hosts to withstand abiotic stress or affect host plant use. In addition to the direct effect of symbionts on aphid phenotypes there may be indirect effects mediated through trophic and non-trophic community interactions. We believe that by using data from barcoding studies to identify bacterial symbionts, this extra, microbial dimension to insect food webs can be better elucidated.This article is part of the themed issue 'From DNA barcodes to biomes'. PMID:27481779

  11. Eicosanoid actions in insect immunology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this chapter we review eicosanoid actions in insect immunity. Eicosanoids are oxygenated metabolites of arachidonic acid (AA) and two other C20 polyunsaturated polyunsaturated fatty acids. Groups of eicosanoids include prostaglandins, lipoxygenase products and epoxyeicosatrienoic acids. These ...

  12. Radar Observation of Insects - Mosquitoes

    NASA Technical Reports Server (NTRS)

    Frost, E.; Downing, J.

    1979-01-01

    Tests were conducted at several sites over the coastal lowlands of New Jersey and over a region of high plains and low mountains in Oklahoma. In one area, a salt marsh in New Jersey, extensive ground tests were combined with laboratory data on expected insect backscatter to arrive at an extremely convincing model of the insect origin of most Dot Angels. A great deal of insight was studied from radar on the buildup and dispersal of insect swarms, since radar can follow where other means of trapping and observation cannot. Data on large-scale behavior as a function of wind and topography are presented. Displayed techniques which show individual or small swarm motion within some larger cloud or mass, or which can show the overall motion over great distances were developed. The influence of wind and terrain on insect motion and dispersal is determined from radar data.

  13. Freshwater Biodiversity and Insect Diversification

    PubMed Central

    Dijkstra, Klaas-Douwe B.; Monaghan, Michael T.; Pauls, Steffen U.

    2016-01-01

    Inland waters cover less than one percent of Earth’s surface, but harbor more than six percent of all insect species: nearly 100,000 species from 12 orders spend one or more life stages in freshwater. Little is known about how this remarkable diversity arose, although allopatric speciation and ecological adaptation are thought to be primary mechanisms. Freshwater habitats are exceptionally susceptible to environmental change, and exhibit marked ecological gradients. The amphibiotic lifestyles of aquatic insects result in complex contributions of extinction and allopatric and non-allopatric speciation in species diversification. In contrast to the lack of evolutionary studies, the ecology and habitat preferences of aquatic insects have been intensively studied, in part because of their widespread use as bio-indicators. The combination of phylogenetics with the extensive ecological data provides a promising avenue for future research, making aquatic insects highly suitable models for the study of ecological diversification. PMID:24160433

  14. Flight of the smallest insects

    NASA Astrophysics Data System (ADS)

    Miller, Laura; Santhanakrishnan, Arvind; Hedrick, Tyson; Robinson, Alice

    2009-11-01

    A vast body of research has described the complexity of flight in insects ranging from the fruit fly, Drosophila melanogaster, to the hawk moth, Manduca sexta. Over this range of scales, flight aerodynamics as well as the relative lift and drag forces generated are surprisingly similar. The smallest flying insects (Re˜10) have received far less attention, although previous work has shown that flight kinematics and aerodynamics can be significantly different. In this presentation, we have used a three-pronged approach that consists of measurements of flight kinematics in the tiny insect Thysanoptera (thrips), measurements of flow velocities using physical models, and direct numerical simulations to compute lift and drag forces. We find that drag forces can be an order of magnitude larger than lift forces, particularly during the clap and fling motion used by all tiny insects recorded to date.

  15. Insect bites and stings (image)

    MedlinePlus

    Even though some insect bites or stings can be extremely painful they usually do not require emergency medical care. Although the stung or bitten area should be carefully observed for signs of infection or reaction to venom.

  16. Preface: Insect Pathology, 2nd ed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect pathology is an essential component of entomology and provides a non-chemical alternative for insect pest management. There are several groups of organisms that can infect and kill insects including viruses, fungi, microsporidia, bacteria, protists, and nematodes. The dilemma in insect patho...

  17. Pollen Recovery from Insects: Light Microscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous insect species feed on the pollen, nectar, and other plant exudates that are associated with flowers. As a result of this feeding activity, pollen becomes attached to the insects. Analysis of the pollen attached to these insects can reveal what insects eat, their dispersal patterns in and...

  18. 7 CFR 51.2290 - Insect injury.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Insect injury. 51.2290 Section 51.2290 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... § 51.2290 Insect injury. Insect injury means that the insect, web, frass or other evidence of...

  19. How Do Insects Help the Environment?

    ERIC Educational Resources Information Center

    Hevel, Gary

    2005-01-01

    There are some 5 to 30 million insect species estimated in the world--and the majority of these have yet to be collected or named by science! Of course, the most well known insects are those that cause disease or compete for human agricultural products, but these insects represent only a small fraction of the world's insect population. In reality,…

  20. 46 CFR 108.215 - Insect screens.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Insect screens. 108.215 Section 108.215 Shipping COAST... Construction and Arrangement Accommodation Spaces § 108.215 Insect screens. (a) Accommodation spaces must be protected against the admission of insects. (b) Insect screens must be installed when natural ventilation...

  1. 7 CFR 51.2122 - Insect injury.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Insect injury. 51.2122 Section 51.2122 Agriculture..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Shelled Almonds Definitions § 51.2122 Insect injury. Insect injury means that the insect, web, or frass is present or there is definite evidence...

  2. 7 CFR 51.2122 - Insect injury.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Insect injury. 51.2122 Section 51.2122 Agriculture..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Shelled Almonds Definitions § 51.2122 Insect injury. Insect injury means that the insect, web, or frass is present or there is definite evidence...

  3. 7 CFR 51.2290 - Insect injury.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Insect injury. 51.2290 Section 51.2290 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... § 51.2290 Insect injury. Insect injury means that the insect, web, frass or other evidence of...

  4. 46 CFR 108.215 - Insect screens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Insect screens. 108.215 Section 108.215 Shipping COAST... Construction and Arrangement Accommodation Spaces § 108.215 Insect screens. (a) Accommodation spaces must be protected against the admission of insects. (b) Insect screens must be installed when natural ventilation...

  5. 7 CFR 51.2008 - Insect injury.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Insect injury. 51.2008 Section 51.2008 Agriculture... Standards for Grades of Filberts in the Shell 1 Definitions § 51.2008 Insect injury. Insect injury means that the insect, frass or web is present inside the nut or the kernel shows definite evidence of...

  6. 46 CFR 108.215 - Insect screens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Insect screens. 108.215 Section 108.215 Shipping COAST... Construction and Arrangement Accommodation Spaces § 108.215 Insect screens. (a) Accommodation spaces must be protected against the admission of insects. (b) Insect screens must be installed when natural ventilation...

  7. 46 CFR 108.215 - Insect screens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Insect screens. 108.215 Section 108.215 Shipping COAST... Construction and Arrangement Accommodation Spaces § 108.215 Insect screens. (a) Accommodation spaces must be protected against the admission of insects. (b) Insect screens must be installed when natural ventilation...

  8. 46 CFR 108.215 - Insect screens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Insect screens. 108.215 Section 108.215 Shipping COAST... Construction and Arrangement Accommodation Spaces § 108.215 Insect screens. (a) Accommodation spaces must be protected against the admission of insects. (b) Insect screens must be installed when natural ventilation...

  9. 7 CFR 51.2008 - Insect injury.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Insect injury. 51.2008 Section 51.2008 Agriculture... Standards for Grades of Filberts in the Shell 1 Definitions § 51.2008 Insect injury. Insect injury means that the insect, frass or web is present inside the nut or the kernel shows definite evidence of...

  10. 7 CFR 51.2008 - Insect injury.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Insect injury. 51.2008 Section 51.2008 Agriculture... Standards for Grades of Filberts in the Shell 1 Definitions § 51.2008 Insect injury. Insect injury means that the insect, frass or web is present inside the nut or the kernel shows definite evidence of...

  11. Don't Let Insects Bug You!

    ERIC Educational Resources Information Center

    Abraham, Doc; Abraham, Katy

    1977-01-01

    Are you one of those people who feel that the only good insect is a dead one? Do you suffer from entomophobia--dread fear of insects? Such attitudes, fears, and prejudices stem from insect ignorance. Authors explain what insects are good for and give students a more realistic and fascinating view of their world. (Editor/RK)

  12. In vitro and in vivo effects of kinin B1 and B2 receptor agonists and antagonists in inbred control and cardiomyopathic hamsters

    PubMed Central

    Hallé, S; Gobeil, F; Ouellette, J; Lambert, C; Regoli, D

    2000-01-01

    The aims of this study were to examine the possible alterations occurring in the effects of kinins on isolated aortae of inbred control (CHF 148) and cardiomyopathic (CHF 146) hamsters of 150–175 and 350–375 days of age.Bradykinin (BK) and desArg9BK contracted isolated aortae (with or without endothelium) of hamsters of both strains and ages. After tissue equilibration (90 min), responses elicited by both kinin agonists were stable over the time of experiments. The patterns of isometric contractions of BK and desArg9BK were however found to be different; desArg9BK had a slower onset and a longer duration of action than BK.Potencies (pEC50 values) of BK in all groups of hamsters were significantly increased by preincubating the tissues with captopril (10−5 M).No differences in the pEC50 values and the Emax values for BK or desArg9BK were seen between isolated vessels from inbred control and cardiomyopathic hamsters.The myotropic effect of BK was inhibited by the selective non peptide antagonist, FR 173657 (pIC50 7.25±0.12 at the bradykinin B2 receptor subtype (B2 receptor)). Those of desArg9BK, at the bradykinin B1 receptor subtype (B1 receptor) were abolished by either R 715 (pIC50 of 7.55±0.05; αE=0), Lys[Leu8]desArg9BK (pIC50 of 7.21±0.01; αE=0.22) or [Leu8]desArg9BK (pIC50 of 7.25±0.02; αE=0.18).FR 173657 had no agonistic activity, exerted a non competitive type of antagonism and was poorly reversible (lasting more than 5 h) from B2 receptor. In vivo, FR 173657 (given per os at 1 and 5 mg kg−1, 1 h before the experiment) antagonized the acute hypotensive effect of BK in anaesthetized hamsters.It is concluded that aging and/or the presence of a congenital cardiovascular disorder in hamsters are not associated with changes in the in vitro aortic responses to either BK or desArg9BK. PMID:10780969

  13. Discontinuous gas exchange in insects.

    PubMed

    Quinlan, Michael C; Gibbs, Allen G

    2006-11-01

    Insect respiratory physiology has been studied for many years, and interest in this area of insect biology has become revitalized recently for a number of reasons. Technical advances have greatly improved the precision, accuracy and ease with which gas exchange can be measured in insects. This has made it possible to go beyond classic models such as lepidopteran pupae and examine a far greater diversity of species. One striking result of recent work is the realization that insect gas exchange patterns are much more diverse than formerly recognized. Current work has also benefited from the inclusion of comparative methods that rigorously incorporate phylogenetic, ecological and life history information. We discuss these advances in the context of the classic respiratory pattern of insects, discontinuous gas exchange. This mode of gas exchange was exhaustively described in moth pupae in the 1950s and 1960s. Early workers concluded that discontinuous gas exchange was an adaptation to reduce respiratory water loss. This idea is no longer universally accepted, and several competing hypotheses have been proposed. We discuss the genesis of these alternative hypotheses, and we identify some of the predictions that might be used to test them. We are pleased to report that what was once a mature discipline, in which the broad parameters and adaptive significance of discontinuous gas exchange were thought to be well understood, is now a thriving and vigorous field of research. PMID:16870512

  14. Insects, infestations and nutrient fluxes

    NASA Astrophysics Data System (ADS)

    Michalzik, B.

    2012-04-01

    Forest ecosystems are characterized by a high temporal and spatial variability in the vertical transfer of energy and matter within the canopy and the soil compartment. The mechanisms and controlling factors behind canopy processes and system-internal transfer dynamics are imperfectly understood at the moment. Seasonal flux diversities and inhomogeneities in throughfall composition have been reported from coniferous and deciduous forests, and in most cases leaf leaching has been considered as principle driver for differences in the amount and quality of nutrients and organic compounds (Tukey and Morgan 1963). Since herbivorous insects and the processes they initiate received less attention in past times, ecologists now emphasize the need for linking biological processes occurring in different ecosystem strata to explain rates and variability of nutrient cycling (Bardgett et al. 1998, Wardle et al. 2004). Consequently, herbivore insects in the canopies of forests are increasingly identified to play an important role for the (re)cycling and availability of nutrients, or, more generally, for the functioning of ecosystems not only in outbreak situations but also at endemic (non-outbreak) density levels (Stadler et al. 2001, Hunter et al. 2003). Before, little attention was paid to insect herbivores when quantifying element and energy fluxes through ecosystems, although the numerous and different functions insects fulfill in ecosystems (e.g. as pollinators, herbivores or detritivores) were unanimously recognized (Schowalter 2000). Amongst the reasons for this restraint was the argument that the total biomass of insects tends to be relatively low compared to the biomass of trees or the pool of soil organic matter (Ohmart et al. 1983). A second argument which was put forward to justify the inferior role of insects in nutrient cycling were the supposed low defoliation losses between 5-10% of the annual leaf biomass, or net primary production, due to insect herbivory under

  15. Line following terrestrial insect biobots.

    PubMed

    Latif, Tahmid; Bozkurt, Alper

    2012-01-01

    The present day technology falls short in offering centimeter scale mobile robots that can function effectively under unknown and dynamic environmental conditions. Insects, on the other hand, exhibit an unmatched ability to navigate through a wide variety of environments and overcome perturbations by successfully maintaining control and stability. In this study, we use neural stimulation systems to wirelessly navigate cockroaches to follow lines to enable terrestrial insect biobots. We also propose a system-on-chip based ZigBee enabled wireless neurostimulation backpack system with on-board tissue-electrode bioelectrical coupling verification. Such a capability ensures an electrochemically safe stimulation and avoids irreversible damage to the interface which is often misinterpreted as habituation of the insect to the applied stimulation. PMID:23366056

  16. Neurosecretion: peptidergic systems in insects

    NASA Astrophysics Data System (ADS)

    Predel, R.; Eckert, Manfred

    Insect neuropeptides are produced in less than 1% of the cells of the central nervous system. Despite this, they are important messenger molecules which influence nearly all physiological processes, including behaviour. They can act as transmitters, modulators and classical hormones, and often exhibit pleiotropic functions when released into the haemolymph. The large number of neuropeptides that has been identified from some of the model organisms among insects underlines the complexity of the neurosecretory system; studies about the coordinated actions of these substances are in their preliminary stages. Recent advances in insect neuropeptide research will be reviewed here, concentrating on the distribution of multiple peptide forms in the central nervous system and adjacent neurohaemal organs, and the role of neuropeptides in eclosion behaviour.

  17. Rice Reoviruses in Insect Vectors.

    PubMed

    Wei, Taiyun; Li, Yi

    2016-08-01

    Rice reoviruses, transmitted by leafhopper or planthopper vectors in a persistent propagative manner, seriously threaten the stability of rice production in Asia. Understanding the mechanisms that enable viral transmission by insect vectors is a key to controlling these viral diseases. This review describes current understanding of replication cycles of rice reoviruses in vector cell lines, transmission barriers, and molecular determinants of vector competence and persistent infection. Despite recent breakthroughs, such as the discoveries of actin-based tubule motility exploited by viruses to overcome transmission barriers and mutually beneficial relationships between viruses and bacterial symbionts, there are still many gaps in our knowledge of transmission mechanisms. Advances in genome sequencing, reverse genetics systems, and molecular technologies will help to address these problems. Investigating the multiple interaction systems among the virus, insect vector, insect symbiont, and plant during natural infection in the field is a central topic for future research on rice reoviruses. PMID:27296147

  18. Flower constancy in insect pollinators

    PubMed Central

    Ratnieks, Francis L.W.

    2011-01-01

    As first noted by Aristotle in honeybee workers, many insect pollinators show a preference to visit flowers of just one species during a foraging trip. This “flower constancy” probably benefits plants, because pollen is more likely to be deposited on conspecific stigmas. But it is less clear why insects should ignore rewarding alternative flowers. Many researchers have argued that flower constancy is caused by constraints imposed by insect nervous systems rather than because flower constancy is itself an efficient foraging method. We argue that this view is unsatisfactory because it both fails to explain why foragers flexibly adjust the degree of flower constancy and does not explain why foragers of closely related species show different degrees of constancy. While limitations of the nervous system exist and are likely to influence flower constancy to some degree, the observed behavioural flexibility suggests that flower constancy is a successful foraging strategy given the insect’s own information about different foraging options. PMID:22446521

  19. Insect growth regulators and insect control: a critical appraisal.

    PubMed Central

    Siddall, J B

    1976-01-01

    Insect growth regulators (IGRs) of the juvenile hormone type alter physiological processes essential to insect development and appear to act specifically on insects. Three natural juvenile hormones have been found in insects but not in other organisms. Future use of antagonists or inhibitors of hormone synthesis may be technically possible as an advantageous extension of pest control by IGRs. A documented survey of the properties, metabolism, toxicology, and uses of the most commercially advanced chemical, methoprene, shows it to be environmentally acceptable and toxicologically innocuous. Derivation of its current use patterns is discussed and limitations on these are noted. Residue levels and their measurement in the ppb region have allowed exemption from the requirement of tolerances in the EPA registered use of methoprene for mosquito control. Tolerances for foods accompany its fully approved use for control of manure breeding flies through a cattle feed supplement. The human health effects of using this chemical appear to be purely beneficial, but further advances through new IGR chemicals appear unlikely without major changes in regulatory and legislative policy. PMID:976222

  20. Insect Screening Results: Assessment of Corn Hybrids for Insect Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During the growing season of 2006, the relatively dry environmental conditions in Tifton, Georgia were favorable for the rapid buildup of corn earworms, providing the potential for considerable damage to the corn crop. Six ear-feeding insects recorded in the order of infestation severity were: the...

  1. Insects as a Nitrogen Source for Plants

    PubMed Central

    Behie, Scott W.; Bidochka, Michael J.

    2013-01-01

    Many plants have evolved adaptations in order to survive in low nitrogen environments. One of the best-known adaptations is that of plant symbiosis with nitrogen-fixing bacteria; this is the major route by which nitrogen is incorporated into plant biomass. A portion of this plant-associated nitrogen is then lost to insects through herbivory, and insects represent a nitrogen reservoir that is generally overlooked in nitrogen cycles. In this review we show three specialized plant adaptations that allow for the recovery of insect nitrogen; that is, plants gaining nitrogen from insects. First, we show specialized adaptations by carnivorous plants in low nitrogen habitats. Insect carnivorous plants such as pitcher plants and sundews (Nepenthaceae/Sarraceniaceae and Drosera respectively) are able to obtain substantial amounts of nitrogen from the insects that they capture. Secondly, numerous plants form associations with mycorrhizal fungi that can provide soluble nitrogen from the soil, some of which may be insect-derived nitrogen, obtained from decaying insects or insect frass. Finally, a specialized group of endophytic, insect-pathogenic fungi (EIPF) provide host plants with insect-derived nitrogen. These soil-inhabiting fungi form a remarkable symbiosis with certain plant species. They can infect a wide range of insect hosts and also form endophytic associations in which they transfer insect-derived nitrogen to the plant. Root colonizing fungi are found in disparate fungal phylogenetic lineages, indicating possible convergent evolutionary strategies between taxa, evolution potentially driven by access to carbon-containing root exudates. PMID:26462427

  2. Insects as a Nitrogen Source for Plants.

    PubMed

    Behie, Scott W; Bidochka, Michael J

    2013-01-01

    Many plants have evolved adaptations in order to survive in low nitrogen environments. One of the best-known adaptations is that of plant symbiosis with nitrogen-fixing bacteria; this is the major route by which nitrogen is incorporated into plant biomass. A portion of this plant-associated nitrogen is then lost to insects through herbivory, and insects represent a nitrogen reservoir that is generally overlooked in nitrogen cycles. In this review we show three specialized plant adaptations that allow for the recovery of insect nitrogen; that is, plants gaining nitrogen from insects. First, we show specialized adaptations by carnivorous plants in low nitrogen habitats. Insect carnivorous plants such as pitcher plants and sundews (Nepenthaceae/Sarraceniaceae and Drosera respectively) are able to obtain substantial amounts of nitrogen from the insects that they capture. Secondly, numerous plants form associations with mycorrhizal fungi that can provide soluble nitrogen from the soil, some of which may be insect-derived nitrogen, obtained from decaying insects or insect frass. Finally, a specialized group of endophytic, insect-pathogenic fungi (EIPF) provide host plants with insect-derived nitrogen. These soil-inhabiting fungi form a remarkable symbiosis with certain plant species. They can infect a wide range of insect hosts and also form endophytic associations in which they transfer insect-derived nitrogen to the plant. Root colonizing fungi are found in disparate fungal phylogenetic lineages, indicating possible convergent evolutionary strategies between taxa, evolution potentially driven by access to carbon-containing root exudates. PMID:26462427

  3. Introducing Virological Concepts Using an Insect Virus.

    ERIC Educational Resources Information Center

    Sheppard, Roger F.

    1980-01-01

    A technique is presented which utilizes wax moth larvae in a laboratory investigation of an insect virus. Describes how an insect virus can be used to introduce undergraduate biology students to laboratory work on viruses and several virological concepts. (SA)

  4. First Aid: Insect Stings and Bites

    MedlinePlus

    ... Can I Protect My Family From Ticks? Are Insect Repellents With DEET Safe for Kids? Bug Bites and Stings Can I Use Bug Killers and Repellents During Pregnancy? Insect Sting Allergy How Do I Watch for Lyme ...

  5. Palaeontology: Chinese amber insects bridge the gap.

    PubMed

    Ross, Andrew

    2014-07-21

    n the study of fossil insects, Chinese amber from Fushun has been largely overlooked. A new study now reveals a highly diverse biota and provides a wealth of new information on the past Asian insect fauna. PMID:25050958

  6. Insects--How To Study Them

    ERIC Educational Resources Information Center

    Matthews, E. G.

    1975-01-01

    Describes an approach to the study of entomology directed at people with no special knowledge of insects. The aim of this approach is to reveal some biological principles by studying insects from an ecological point of view. (GS)

  7. The Curious Connection Between Insects and Dreams

    PubMed Central

    Klein, Barrett A.

    2011-01-01

    A majority of humans spend their waking hours surrounded by insects, so it should be no surprise that insects also appear in humans’ dreams as we sleep. Dreaming about insects has a peculiar history, marked by our desire to explain a dream’s significance and by the tactic of evoking emotions by injecting insects in dream-related works of art, film, music, and literature. I surveyed a scattered literature for examples of insects in dreams, first from the practices of dream interpretation, psychiatry, and scientific study, then from fictional writings and popular culture, and finally in the etymology of entomology by highlighting insects with dream-inspired Latinate names. A wealth of insects in dreams, as documented clinically and culturally, attests to the perceived relevance of dreams and to the ubiquity of insects in our lives. PMID:26467945

  8. The Curious Connection Between Insects and Dreams.

    PubMed

    Klein, Barrett A

    2011-01-01

    A majority of humans spend their waking hours surrounded by insects, so it should be no surprise that insects also appear in humans' dreams as we sleep. Dreaming about insects has a peculiar history, marked by our desire to explain a dream's significance and by the tactic of evoking emotions by injecting insects in dream-related works of art, film, music, and literature. I surveyed a scattered literature for examples of insects in dreams, first from the practices of dream interpretation, psychiatry, and scientific study, then from fictional writings and popular culture, and finally in the etymology of entomology by highlighting insects with dream-inspired Latinate names. A wealth of insects in dreams, as documented clinically and culturally, attests to the perceived relevance of dreams and to the ubiquity of insects in our lives. PMID:26467945

  9. Comparative effects of pinacidil and prazosin on blood pressure, weight, plasma volume, the renin-angiotensin-aldosterone system, and the renal kallikrein-kinin system in patients with essential hypertension.

    PubMed

    Solomon, R J; Weinberg, M S

    1987-12-01

    Patients with essential hypertension were randomized to treatment with either prazosin or pinacidil, a new direct-acting vasodilator. Factors that might modulate the antihypertensive response and result in pseudotolerance to these drugs were measured before initiation of therapy and following 12 weeks of treatment. Despite significant reductions in blood pressure, pinacidil and prazosin did not produce an increase in plasma volume, did not activate the renin-angiotensin-aldosterone system, and did not interfere with the renal kallikrein-kinin system. The data fail to reveal evidence of physiologic compensatory changes that would lead to the development of pseudotolerance. PMID:3330989

  10. The Seat of Insect Learning.

    ERIC Educational Resources Information Center

    Dyer, Fred C.

    1997-01-01

    Describes the role of mushroom bodies--cup-shaped structures perched atop the brain of an insect--in learning. Mushroom bodies may help fruit flies in learning meaningful odors, cockroaches in spatial learning, and honeybees both in locating pollen and nectar and in navigating back to the colony. (PVD)

  11. Evolution of insect olfactory receptors

    PubMed Central

    Missbach, Christine; Dweck, Hany KM; Vogel, Heiko; Vilcinskas, Andreas; Stensmyr, Marcus C; Hansson, Bill S; Grosse-Wilde, Ewald

    2014-01-01

    The olfactory sense detects a plethora of behaviorally relevant odor molecules; gene families involved in olfaction exhibit high diversity in different animal phyla. Insects detect volatile molecules using olfactory (OR) or ionotropic receptors (IR) and in some cases gustatory receptors (GRs). While IRs are expressed in olfactory organs across Protostomia, ORs have been hypothesized to be an adaptation to a terrestrial insect lifestyle. We investigated the olfactory system of the primary wingless bristletail Lepismachilis y-signata (Archaeognatha), the firebrat Thermobia domestica (Zygentoma) and the neopteran leaf insect Phyllium siccifolium (Phasmatodea). ORs and the olfactory coreceptor (Orco) are with very high probability lacking in Lepismachilis; in Thermobia we have identified three Orco candidates, and in Phyllium a fully developed OR/Orco-based system. We suggest that ORs did not arise as an adaptation to a terrestrial lifestyle, but evolved later in insect evolution, with Orco being present before the appearance of ORs. DOI: http://dx.doi.org/10.7554/eLife.02115.001 PMID:24670956

  12. The insect SNMP gene family

    Technology Transfer Automated Retrieval System (TEKTRAN)

    SNMPs are membrane proteins that have been shown to associate with chemosensory neurons in insects; in Drosophila melanogaster, SNMP1 has been shown to be essential for the detection of the pheromone cis vaccenyl acetate (Benton et al., 2001; Jin et al., 2008). To extend these observations to other ...

  13. Bug City: Aquatic Insects [Videotape].

    ERIC Educational Resources Information Center

    1998

    "Bug City" is a video series created to help children learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic photography, fun…

  14. Making Connections with Insect Royalty.

    ERIC Educational Resources Information Center

    Hobbie, Ann

    2000-01-01

    Describes a one-month sixth grade class activity with monarch butterflies called Monarch in the Classroom. Students learn about insects, especially the class material butterflies, including their life cycle, eating habits, migration, and how they overwinter. The lesson plan covers sorting animals, focusing on features, analyzing the community for…

  15. Rearing insects on artificial diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insects are reared in the laboratory for various purposes. They may be reared either on their natural food or artificial diets. Developing artificial diets may be difficult and time consuming but once optimized, artificial diets usually are simple to prepare and easy to use. Because they are process...

  16. Transposable elements for insect transformation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The germ-line of more than 35 species from five orders of insects have been genetically transformed, using vectors derived from Class II transposable elements. Initially the P and hobo vector systems developed for D. melanogaster were not applicable to other species, but four transposons found in ot...

  17. Plant defense against insect herbivory

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Damage to maize crops by insect herbivores such as beet and fall army worm causes significant impact in the Southern United States in terms of both yield loss and insecticide use. Enhanced understanding of how maize can defend itself against such attacks at a molecular level will enable development ...

  18. Exaggerated trait growth in insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal structures occasionally attain extreme proportions, eclipsing in size other, surrounding body parts. We review insect examples of exaggerated traits, such as the mandibles of stag beetles, the claspers of praying mantises, the elongated hindlimbs of grasshoppers, and the giant heads of soldie...

  19. Insects Affecting Man. MP-21.

    ERIC Educational Resources Information Center

    Lawson, Fred A.; Spackman, Everett

    The insects discussed in this document are those which have a direct effect upon humans either through a permanent association, as with lice, or a temporary association in the case of flies, bees, wasps, and spiders. In each case, life cycles and identifying characteristics are presented with remarks about the specific effect incurred by man. (CS)

  20. Nontoxic Antifreeze for Insect Traps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Propylene glycol in water is a safe and effective alternative to ethylene glycol as a capture liquid in insect traps (pitfalls, flight intercepts, pan traps). Propylene glycol formulations are readily available because it is the primary (95%) ingredient in certain automotive antifreeze formulations...

  1. Using new technology and insect behavior in novel terrestrial and flying insect traps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect traps are commonly used for both population sampling and insect control, the former as part of an integrated pest management (IPM) program. We developed traps for two insects, one as part of a pesticide based IPM system and the other for population control. Our IPM trap is for crawling insect...

  2. Buckling failures in insect exoskeletons.

    PubMed

    Parle, Eoin; Herbaj, Simona; Sheils, Fiona; Larmon, Hannah; Taylor, David

    2016-02-01

    Thin walled tubes are often used for load-bearing structures, in nature and in engineering, because they offer good resistance to bending and torsion at relatively low weight. However, when loaded in bending they are prone to failure by buckling. It is difficult to predict the loading conditions which cause buckling, especially for tubes whose cross sections are not simple shapes. Insights into buckling prevention might be gained by studying this phenomenon in the exoskeletons of insects and other arthropods. We investigated the leg segments (tibiae) of five different insects: the locust (Schistocerca gergaria), American cockroach (Periplaneta americana), death's head cockroach (Blaberus discoidalis), stick insect (Parapachymorpha zomproi) and bumblebee (Bombus terrestris audax). These were tested to failure in cantilever bending and modelled using finite element analysis (FEA). The tibiae of the locust and the cockroaches were found to be approximately circular in shape. Their buckling loads were well predicted by linear elastic FEA, and also by one of the analytical solutions available in the literature for elastic buckling. The legs of the stick insect are also circular in cross section but have several prominent longitudinal ridges. We hypothesised that these ridges might protect the legs against buckling but we found that this was not the case: the loads necessary for elastic buckling were not reached in practice because yield occurred in the material, causing plastic buckling. The legs of bees have a non-circular cross section due to a pollen-carrying feature (the corbicula). We found that this did not significantly affect their resistance to buckling. Our results imply that buckling is the dominant failure mode in the tibia of insects; it likely to be a significant consideration for other arthropods and any organisms with stiff exoskeletons. The interactions displayed here between material properties and cross sectional geometry may provide insights for the

  3. The insect SNMP gene family.

    PubMed

    Vogt, Richard G; Miller, Natalie E; Litvack, Rachel; Fandino, Richard A; Sparks, Jackson; Staples, Jon; Friedman, Robert; Dickens, Joseph C

    2009-07-01

    SNMPs are membrane proteins observed to associate with chemosensory neurons in insects; in Drosophila melanogaster, SNMP1 has been shown to be essential for the detection of the pheromone cis-vaccenyl acetate (CVA). SNMPs are one of three insect gene clades related to the human fatty acid transporter CD36. We previously characterized the CD36 gene family in 4 insect Orders that effectively cover the Holometabola, or some 80% of known insect species and the 300 million years of evolution since this lineage emerged: Lepidoptera (e.g. Bombyx mori, Antheraea polyphemus, Manduca sexta, Heliothis virescens, Helicoverpa assulta, Helicoverpa armigera, Mamestra brassicae); Diptera (D. melanogaster, Drosophila pseudoobscura, Aedes aegypti, Anopheles gambiae, Culex pipiens quinquefasciatus); Hymenoptera (Apis mellifera); and Coleoptera (Tribolium castaneum). This previous study suggested a complex topography within the SNMP clade including a strongly supported SNMP1 sub-clade plus additional SNMP genes. To further resolve the SNMP clade here, we used cDNA sequences of SNMP1 and SNMP2 from various Lepidoptera species, D. melanogaster and Ae. aegypti, as well as BAC derived genomic sequences from Ae. aegypti as models for proposing corrected sequences of orthologues in the D. pseudoobscura and An. gambiae genomes, and for identifying orthologues in the B. mori and C. pipiens q. genomes. We then used these sequences to analyze the SNMP clade of the insect CD36 gene family, supporting the existence of two well supported sub-clades, SNMP1 and SNMP2, throughout the dipteran and lepidopteran lineages, and plausibly throughout the Holometabola and across a broad evolutionary time scale. We present indirect evidence based on evolutionary selection (dN/dS) that the dipteran SNMPs are expressed as functional proteins. We observed expansions of the SNMP1 sub-clade in C. pipiens q. and T. castaneum suggesting that the SNMP1s may have an expanded functional role in these species. PMID

  4. Applications of acoustics in insect pest management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Acoustic technology has been applied for many years in studies of insect communication and in the monitoring of calling-insect population levels, geographic distributions, and diversity, as well as in the detection of cryptic insects in soil, wood, container crops, and stored products. Acoustic devi...

  5. Insect Control (1): Use of Pheromones

    ERIC Educational Resources Information Center

    Marx, Jean L.

    1973-01-01

    Discusses current research relating to the use of pheromones as a means of controlling insect pests. These chemicals, which are secreted by insects to affect the behavior of other individuals of the same species, may be used to eliminate pests without destroying their predators and other beneficial insects. (JR)

  6. 21 CFR 1250.95 - Insect control.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Insect control. 1250.95 Section 1250.95 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.95 Insect control. Vessels shall be maintained free of infestation by flies, mosquitoes, fleas, lice, and other insects known to be vectors...

  7. 21 CFR 1250.95 - Insect control.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Insect control. 1250.95 Section 1250.95 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.95 Insect control. Vessels shall be maintained free of infestation by flies, mosquitoes, fleas, lice, and other insects known to be vectors...

  8. 21 CFR 1250.95 - Insect control.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Insect control. 1250.95 Section 1250.95 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.95 Insect control. Vessels shall be maintained free of infestation by flies, mosquitoes, fleas, lice, and other insects known to be vectors...

  9. Radar, Insect Population Ecology, and Pest Management

    NASA Technical Reports Server (NTRS)

    Vaughn, C. R. (Editor); Wolf, W. (Editor); Klassen, W. (Editor)

    1979-01-01

    Discussions included: (1) the potential role of radar in insect ecology studies and pest management; (2) the potential role of radar in correlating atmospheric phenomena with insect movement; (3) the present and future radar systems; (4) program objectives required to adapt radar to insect ecology studies and pest management; and (5) the specific action items to achieve the objectives.

  10. 21 CFR 1250.95 - Insect control.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Insect control. 1250.95 Section 1250.95 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.95 Insect control. Vessels shall be maintained free of infestation by flies, mosquitoes, fleas, lice, and other insects known to be vectors...

  11. 21 CFR 1250.95 - Insect control.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Insect control. 1250.95 Section 1250.95 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.95 Insect control. Vessels shall be maintained free of infestation by flies, mosquitoes, fleas, lice, and other insects known to be vectors...

  12. Mechanisms by which pesticides affect insect immunity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The known effects of pesticides on insect immunity is reviewed here. A basic understanding of these interactions is needed for several reasons, including to improve methods for controlling pest insects in agricultural settings, for controlling insect vectors of human diseases, and for reducing morta...

  13. Current internal exposure to pesticides in children and adolescents in Germany: blood plasma levels of pentachlorophenol (PCP), lindane (gamma-HCH), and dichloro(diphenyl)ethylene (DDE), a biostable metabolite of dichloro(diphenyl)trichloroethane (DDT).

    PubMed

    Heudorf, U; Angerer, J; Drexler, H

    2003-10-01

    Pesticides are widely used throughout the world in agriculture to protect crops, and in public health to control diseases transmitted by animal vectors or intermediate hosts. After the prohibition of organochlorines such as DDT internal exposure of the general population to the organochlorines has been reduced markedly. Herein, current internal exposure of children and adolescents in an urban area in Germany to PCP, lindane, and DDT/E is reported. One hundred and thirty children and adolescents took part in this voluntary investigation. All of them stated they had never used pesticides in their homes or for medical reasons. Blood plasma was analysed for pentachlorophenol (PCP), lindane (gamma-HCH), and dichloro(diphenyl)ethylene (DDE), a biostable metabolite of dichloro(diphenyl)trichloroethane (DDT), using gas chromatography/electron capture detection according to well established methods approved by the Deutsche Forschungsgemeinschaft. Median (and 95th percentiles) in the age groups < 6, 6- < 12, and 12- < 18 years of age were (microgram/l): DDE: 0.75 (4.45), 0.95 (5.04), 0.89 (8.77); DDT: < 0.1 (0.22), < 0.1 (0.25), < 0.1 (0.30); PCP: 2.48 (17.32), 2.69 (5.85), 2.08 (8.04); lindane: < 0.1 (0.12, < 0.1 (0.08), < 0.1 (0.09). High levels of internal exposure to DDT in two girls were probably obtained during a holiday stay in India; high PCP-levels in two other girls were caused by a leather jacket impregnated with PCP, and a holiday abroad, respectively. Current background levels of internal exposure to organochlorine insecticides in children and adolescents in Germany are quantified. Exposure to these substances in the general population is thought to occur mainly via residues in food, which are low in general, today. In special cases, however, individual exposures may be dominated by other sources, i.e. impregnated leather clothes. PMID:14626896

  14. The kinin B1 receptor antagonist SSR240612 reverses tactile and cold allodynia in an experimental rat model of insulin resistance

    PubMed Central

    Dias, J P; Ismael, M A; Pilon, M; de Champlain, J; Ferrari, B; Carayon, P; Couture, R

    2007-01-01

    Background and purpose: Diabetes causes sensory polyneuropathy with associated pain in the form of tactile allodynia and thermal hyperalgesia which are often intractable and resistant to current therapy. This study tested the beneficial effects of the non-peptide and orally active kinin B1 receptor antagonist SSR240612 against tactile and cold allodynia in a rat model of insulin resistance. Experimental approach: Rats were fed with 10% D-glucose for 12 weeks and effects of orally administered SSR240612 (0.3–30 mg kg−1) were determined on the development of tactile and cold allodynia. Possible interference of SSR240612 with vascular oxidative stress and pancreatic function was also addressed. Key results: Glucose-fed rats exhibited tactile and cold allodynia, increases in systolic blood pressure and higher plasma levels of insulin and glucose, at 12 weeks. SSR240612 blocked tactile and cold allodynia at 3 h (ID50=5.5 and 7.1 mg kg−1, respectively) in glucose-fed rats but had no effect in control rats. The antagonist (10 mg kg−1) had no effect on plasma glucose and insulin, insulin resistance (HOMA index) and aortic superoxide anion production in glucose-fed rats. Conclusions and implications: We provide the first evidence that the B1 receptors are involved in allodynia in an experimental rat model of insulin resistance. Allodynia was alleviated by SSR240612 most likely through a direct inhibition of B1 receptors affecting spinal cord and/or sensory nerve excitation. Thus, orally active non-peptide B1 receptor antagonists should have clinical therapeutic potential in the treatment of sensory polyneuropathy. PMID:17618300

  15. Relationship between the gene polymorphisms of kallikrein-kinin system and Alzheimer’s disease in a Hunan Han Chinese population

    PubMed Central

    Deng, Yanyao; Hou, Deren; Tian, Mi; Li, Wei; Feng, Xialu; Yu, Zhuling

    2015-01-01

    This study aimed to determine the connection between polymorphisms of kallikrein kinin system including KLK1 (rs5516), KNG1 (rs710446, rs2304456) and ACE (rs4291, rs4309, rs4343) and late-onset Alzheimer’s disease (LOAD). The research was conducted as a case-control study, comprising 201 AD patients in the AD group, and 257 healthy subjects as the control group. PCR amplification and matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) were used to detect the six polymorphisms (rs5516 in KLK1; rs710446, rs2304456 in KNG1; rs4291, rs4309, rs4343 in ACE) from both groups. No statistically significant difference was found between the genotype and allelotype distributions of rs5516, rs710446, rs2304456, rs4291 and rs4343 (P>0.05). The differences between the genotype and allelotype distributions of the rs4309 were statistically significant (P<0.05). Haplotype analysis confirmed the existence of three haplotypes (AG, AT, GT) composed of rs710446/rs2304456, and six haplotypes (ATA, ACA, TCA, TCG, TTA, TTG) composed of rs4291/rs4309/rs4343, among which the distribution of ATA, ACA, TCA between the two groups was statistically significant difference (P<0.05). Our study showed that the polymorphisms of rs5516, rs710446, rs2304456, rs4291 and rs4343 is not related to the incidence of LOAD. The polymorphisms of rs4309 may be related to LOAD, as well as ATA, ACA, and TCA haplotype composed of rs4291/rs4309/rs4343. PMID:26884824

  16. Insect diversity in the fossil record

    NASA Technical Reports Server (NTRS)

    Labandeira, C. C.; Sepkoski, J. J. Jr; Sepkoski JJ, J. r. (Principal Investigator)

    1993-01-01

    Insects possess a surprisingly extensive fossil record. Compilation of the geochronologic ranges of insect families demonstrates that their diversity exceeds that of preserved vertebrate tetrapods through 91 percent of their evolutionary history. The great diversity of insects was achieved not by high origination rates but rather by low extinction rates comparable to the low rates of slowly evolving marine invertebrate groups. The great radiation of modern insects began 245 million years ago and was not accelerated by the expansion of angiosperms during the Cretaceous period. The basic trophic machinery of insects was in place nearly 100 million years before angiosperms appeared in the fossil record.

  17. Fungal allelochemicals in insect pest management.

    PubMed

    Holighaus, Gerrit; Rohlfs, Marko

    2016-07-01

    Interactions between insects and fungi are widespread, and important mediators of these interactions are fungal chemicals that can therefore be considered as allelochemicals. Numerous studies suggest that fungal chemicals can affect insects in many different ways. Here, we apply the terminology established by insect-plant ecologists for categorizing the effect of fungal allelochemicals on insects and for evaluating the application potential of these chemicals in insect pest management. Our literature survey shows that fungal volatile and non-volatile chemicals have an enormous potential to influence insect behavior and fitness. Many of them still remain to be discovered, but some recent examples of repellents and toxins could open up new ways for developing safe insect control strategies. However, we also identified shortcomings in our understanding of the chemical ecology of insect-fungus interactions and the way they have been investigated. In particular, the mode-of-action of fungal allelochemicals has often not been appropriately designated or examined, and the way in which induction by insects affects fungal chemical diversity is poorly understood. This review should raise awareness that in-depth ecological studies of insect-fungus interactions can reveal novel allelochemicals of particular benefit for the development of innovative insect pest management strategies. PMID:27147531

  18. Insects as alternative hosts for phytopathogenic bacteria.

    PubMed

    Nadarasah, Geetanchaly; Stavrinides, John

    2011-05-01

    Phytopathogens have evolved specialized pathogenicity determinants that enable them to colonize their specific plant hosts and cause disease, but their intimate associations with plants also predispose them to frequent encounters with herbivorous insects, providing these phytopathogens with ample opportunity to colonize and eventually evolve alternative associations with insects. Decades of research have revealed that these associations have resulted in the formation of bacterial-vector relationships, in which the insect mediates dissemination of the plant pathogen. Emerging research, however, has highlighted the ability of plant pathogenic bacteria to use insects as alternative hosts, exploiting them as they would their primary plant host. The identification of specific bacterial genetic determinants that mediate the interaction between bacterium and insect suggests that these interactions are not incidental, but have likely arisen following the repeated association of microorganisms with particular insects over evolutionary time. This review will address the biology and ecology of phytopathogenic bacteria that interact with insects, including the traditional role of insects as vectors, as well as the newly emerging paradigm of insects serving as alternative primary hosts. Also discussed is one case where an insect serves as both host and vector, which may represent a transitionary stage in the evolution of insect-phytopathogen associations. PMID:21251027

  19. Insect sodium channels and insecticide resistance

    PubMed Central

    2011-01-01

    Voltage-gated sodium channels are essential for the generation and propagation of action potentials (i.e., electrical impulses) in excitable cells. Although most of our knowledge about sodium channels is derived from decades of studies of mammalian isoforms, research on insect sodium channels is revealing both common and unique aspects of sodium channel biology. In particular, our understanding of the molecular dynamics and pharmacology of insect sodium channels has advanced greatly in recent years, thanks to successful functional expression of insect sodium channels in Xenopus oocytes and intensive efforts to elucidate the molecular basis of insect resistance to insecticides that target sodium channels. In this review, I discuss recent literature on insect sodium channels with emphases on the prominent role of alternative splicing and RNA editing in the generation of functionally diverse sodium channels in insects and the current understanding of the interactions between insect sodium channels and insecticides. PMID:17206406

  20. Immunity in a Social Insect

    NASA Astrophysics Data System (ADS)

    Rosengaus, Rebeca B.; Traniello, James F. A.; Chen, Tammy; Brown, Julie J.; Karp, Richard D.

    Although pathogens appear to have exerted significant selective pressure on various aspects of sociality, mechanisms of disease resistance in the social insects are poorly understood. We report here on an immune response to infection by the dampwood termite, Zootermopsis angusticollis. Nymphs immunized with an injection of 7.6×107, 7.6×105, or 7.6×104 cells/ml glutaraldehyde-killed solution of the bacterium Pseudomonas aeruginosa had significantly higher survivorship than controls following a challenge with a lethal concentration of active bacteria. Similarly, nymphs exposed to a 9×10-1 spores/ml suspension of the fungus Metarhizium anisopliae had higher survivorship than controls after a challenge with a lethal concentration of spores. Prior exposure to a pathogen thus conferred upon termites a degree of protection during a subsequent encounter with the same pathogen. This represents the first demonstration of immune function in vivo in a social insect.

  1. Visual homing: an insect perspective.

    PubMed

    Zeil, Jochen

    2012-04-01

    The ability to learn the location of places in the world and to revisit them repeatedly is crucial for all aspects of animal life on earth. It underpins animal foraging, predator avoidance, territoriality, mating, nest construction and parental care. Much theoretical and experimental progress has recently been made in identifying the sensory cues and the computational mechanisms that allow insects (and robots) to find their way back to places, while the neurobiological mechanisms underlying navigational abilities are beginning to be unravelled in vertebrate and invertebrate models. Studying visual homing in insects is interesting, because they allow experimentation and view-reconstruction under natural conditions, because they are likely to have evolved parsimonious, yet robust solutions to the homing problem and because they force us to consider the viewpoint of navigating animals, including their sensory and computational capacities. PMID:22221863

  2. Corpse Management in Social Insects

    PubMed Central

    Sun, Qian; Zhou, Xuguo

    2013-01-01

    Undertaking behavior is an essential adaptation to social life that is critical for colony hygiene in enclosed nests. Social insects dispose of dead individuals in various fashions to prevent further contact between corpses and living members in a colony. Focusing on three groups of eusocial insects (bees, ants, and termites) in two phylogenetically distant orders (Hymenoptera and Isoptera), we review mechanisms of death recognition, convergent and divergent behavioral responses toward dead individuals, and undertaking task allocation from the perspective of division of labor. Distinctly different solutions (e.g., corpse removal, burial and cannibalism) have evolved, independently, in the holometabolous hymenopterans and hemimetabolous isopterans toward the same problem of corpse management. In addition, issues which can lead to a better understanding of the roles that undertaking behavior has played in the evolution of eusociality are discussed. PMID:23569436

  3. Visual Navigation in Nocturnal Insects.

    PubMed

    Warrant, Eric; Dacke, Marie

    2016-05-01

    Despite their tiny eyes and brains, nocturnal insects have evolved a remarkable capacity to visually navigate at night. Whereas some use moonlight or the stars as celestial compass cues to maintain a straight-line course, others use visual landmarks to navigate to and from their nest. These impressive abilities rely on highly sensitive compound eyes and specialized visual processing strategies in the brain. PMID:27053732

  4. Benzoquinolinediones: activity as insect teratogens

    SciTech Connect

    Walton, B.T.; Ho, C.H.; Ma, C.Y.; O'Neill, E.G.; Kao, G.L.

    1983-10-28

    Morphological abnormalities including extra compound eyes, extra heads, and distally duplicated legs were generated in cricket embryos by treating eggs with single doses of either benz(g)isoquinoline-5,10-dione or benzo(h)quinoline-5,6-dione. Slight structural modifications of the molecules resulted in a loss of teratogenic activity, although embryotoxicity occurred. These potent insect teratogens can be used for analysis of developmental events during embryogenesis. 13 references, 4 figures, 1 table.

  5. Gut immunity in Lepidopteran insects.

    PubMed

    Wu, Kai; Yang, Bing; Huang, Wuren; Dobens, Leonard; Song, Hongsheng; Ling, Erjun

    2016-11-01

    Lepidopteran insects constitute one of the largest fractions of animals on earth, but are considered pests in their relationship with man. Key to the success of this order of insects is its ability to digest food and absorb nutrition, which takes place in the midgut. Because environmental microorganisms can easily enter Lepidopteran guts during feeding, the innate immune response guards against pathogenic bacteria, virus and microsporidia that can be devoured with food. Gut immune responses are complicated by both resident gut microbiota and the surrounding peritrophic membrane and are distinct from immune responses in the body cavity, which depend on the function of the fat body and hemocytes. Due to their relevance to agricultural production, studies of Lepidopteran insect midgut and immunity are receiving more attention, and here we summarize gut structures and functions, and discuss how these confer immunity against different microorganisms. It is expected that increased knowledge of Lepidopteran gut immunity may be utilized for pest biological control in the future. PMID:26872544

  6. Macroecology of local insect communities

    NASA Astrophysics Data System (ADS)

    Krüger, Oliver; McGavin, George C.

    2000-01-01

    The inter-relationships between animal body weight, range size, species richness and abundance are currently the basis of macroecology. Using 41 099 insects sampled from 31 Acacia tree canopies in north-east Tanzania, we first documented the basic macroecological patterns. The relationship between body weight and both species richness and abundance was polygonal with the highest insect species richness and abundance occurring at intermediate body weights. Across individual tree communities, the most statistically robust relationships were found between range size, abundance and species richness and they were all linear. In a second part, we focused on the positive abundance-range size relationship and we could test predictions of six of the eight proposed hypotheses to explain this widely documented pattern of community structure. The relationship is most likely explained by the metapopulation hypothesis stating that with more patches being occupied, local abundance in a given patch increases due to a higher rate of immigration from nearby patches. In addition, we found high slopes for the species-area relationship, typical of island systems and thus it seems reasonable to characterise Acacia trees in the savannah as habitat islands for insects.

  7. Herbivory increases diversification across insect clades

    PubMed Central

    Wiens, John J.; Lapoint, Richard T.; Whiteman, Noah K.

    2015-01-01

    Insects contain more than half of all living species, but the causes of their remarkable diversity remain poorly understood. Many authors have suggested that herbivory has accelerated diversification in many insect clades. However, others have questioned the role of herbivory in insect diversification. Here, we test the relationships between herbivory and insect diversification across multiple scales. We find a strong, positive relationship between herbivory and diversification among insect orders. However, herbivory explains less variation in diversification within some orders (Diptera, Hemiptera) or shows no significant relationship with diversification in others (Coleoptera, Hymenoptera, Orthoptera). Thus, we support the overall importance of herbivory for insect diversification, but also show that its impacts can vary across scales and clades. In summary, our results illuminate the causes of species richness patterns in a group containing most living species, and show the importance of ecological impacts on diversification in explaining the diversity of life. PMID:26399434

  8. Raindrops push and splash flying insects

    NASA Astrophysics Data System (ADS)

    Dickerson, Andrew K.; Shankles, Peter G.; Hu, David L.

    2014-02-01

    In their daily lives, flying insects face a gauntlet of environmental challenges, from wind gusts to raindrop impacts. In this combined experimental and theoretical study, we use high-speed videography to film raindrop collisions upon both flying insects and dynamically scaled spherical mimics. We identify three outcomes of the collision based upon the insect's mass and characteristic size: drops push the insect while remaining intact, coat the insect, and splash. We present a mathematical model that predicts impact force and outcome consistent with those found in experiments. Small insects such as gnats and flies are pushed by raindrops that remain intact upon impact; conversely, large flyers such as locusts and micro-aerial vehicles cause drops to splash. We identify a critical mass of 0.3 g for which flyers achieve both peak acceleration (100 g) and applied force (104 dyn) from incoming raindrops; designs of similarly massed flying robots should be avoided.

  9. Insect stereopsis demonstrated using a 3D insect cinema

    PubMed Central

    Nityananda, Vivek; Tarawneh, Ghaith; Rosner, Ronny; Nicolas, Judith; Crichton, Stuart; Read, Jenny

    2016-01-01

    Stereopsis - 3D vision – has become widely used as a model of perception. However, all our knowledge of possible underlying mechanisms comes almost exclusively from vertebrates. While stereopsis has been demonstrated for one invertebrate, the praying mantis, a lack of techniques to probe invertebrate stereopsis has prevented any further progress for three decades. We therefore developed a stereoscopic display system for insects, using miniature 3D glasses to present separate images to each eye, and tested our ability to deliver stereoscopic illusions to praying mantises. We find that while filtering by circular polarization failed due to excessive crosstalk, “anaglyph” filtering by spectral content clearly succeeded in giving the mantis the illusion of 3D depth. We thus definitively demonstrate stereopsis in mantises and also demonstrate that the anaglyph technique can be effectively used to deliver virtual 3D stimuli to insects. This method opens up broad avenues of research into the parallel evolution of stereoscopic computations and possible new algorithms for depth perception. PMID:26740144

  10. Insect stereopsis demonstrated using a 3D insect cinema.

    PubMed

    Nityananda, Vivek; Tarawneh, Ghaith; Rosner, Ronny; Nicolas, Judith; Crichton, Stuart; Read, Jenny

    2016-01-01

    Stereopsis - 3D vision - has become widely used as a model of perception. However, all our knowledge of possible underlying mechanisms comes almost exclusively from vertebrates. While stereopsis has been demonstrated for one invertebrate, the praying mantis, a lack of techniques to probe invertebrate stereopsis has prevented any further progress for three decades. We therefore developed a stereoscopic display system for insects, using miniature 3D glasses to present separate images to each eye, and tested our ability to deliver stereoscopic illusions to praying mantises. We find that while filtering by circular polarization failed due to excessive crosstalk, "anaglyph" filtering by spectral content clearly succeeded in giving the mantis the illusion of 3D depth. We thus definitively demonstrate stereopsis in mantises and also demonstrate that the anaglyph technique can be effectively used to deliver virtual 3D stimuli to insects. This method opens up broad avenues of research into the parallel evolution of stereoscopic computations and possible new algorithms for depth perception. PMID:26740144

  11. Delayed insect access alters carrion decomposition and necrophagous insect community assembly

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vertebrate carrion in terrestrial ecosystems is an unpredictable, ephemeral resource pulse that contributes to local biodiversity and nutrient transformation dynamics. We hypothesized that delayed insect access to carrion would demonstrate marked shifts in necrophagous insect community structure, t...

  12. Ellipsometry of diffractive insect reflectors

    NASA Astrophysics Data System (ADS)

    Brink, D. J.; Lee, M. E.

    1996-04-01

    Scales on the wings of certain insects, such as Trichoplusia orichalcea, exhibit a surface microstructure resembling a fine diffraction grating. Diffraction of incident light by this structure is responsible for many of the optical properties of the wings of this moth, such as the metallic yellow color and the almost-specular reflection and polarization properties of the scattered radiation. It is shown that by the use of null ellipsometry the polarization characteristics can be used to obtain the optical constants of the scale material. Theoretical considerations and suitable experimental conditions are discussed and evaluated.

  13. Feeling what an insect feels.

    PubMed

    Mohand Ousaid, Abdenbi; Millet, Guillaume; Haliyo, Sinan; Régnier, Stéphane; Hayward, Vincent

    2014-01-01

    We describe a manually operated, bilateral mechanical scaling instrument that simultaneously magnifies microscopic forces and reduces displacements with quasi-perfect transparency. In contrast with existing micro-teleoperation designs, the system is unconditionally stable for any scaling gains and interaction curves. In the present realization, the work done by the hand is more than a million times that done by a microscopic probe so that one can feel complete interaction cycles with water and compare them to what is felt when an insect leg interacts with a wet surface. PMID:25271636

  14. Feeling What an Insect Feels

    PubMed Central

    Mohand Ousaid, Abdenbi; Millet, Guillaume; Haliyo, Sinan; Régnier, Stéphane; Hayward, Vincent

    2014-01-01

    We describe a manually operated, bilateral mechanical scaling instrument that simultaneously magnifies microscopic forces and reduces displacements with quasi-perfect transparency. In contrast with existing micro-teleoperation designs, the system is unconditionally stable for any scaling gains and interaction curves. In the present realization, the work done by the hand is more than a million times that done by a microscopic probe so that one can feel complete interaction cycles with water and compare them to what is felt when an insect leg interacts with a wet surface. PMID:25271636

  15. Insect hormones and their derivatives as insecticides

    PubMed Central

    Bowers, William S.

    1971-01-01

    The hormonal control of moulting, reproduction, and diapause in insects has little or no relationship to any similar phenomena in other animals, and the hormones involved in these processes are unlike any known hormones of vertebrates. The availability of pure chemicals with high biological activity has permitted an astonishing increase in research on insect hormones. At present, understanding of insect endocrinology is far too incomplete to justify much speculation about the possibility of using insect hormones as insecticides. However, the preliminary studies discussed in this paper give reason for hope, and the results justify further effort. PMID:4938025

  16. A magnetic fluid microdevice using insect wings

    NASA Astrophysics Data System (ADS)

    Sudo, S.; Tsuyuki, K.; Yano, T.; Takagi, K.

    2008-05-01

    A magnetic fluid microdevice using Diptera insect wings is proposed and constructed. The magnetic fluid device is composed of insect wings, a small permanent magnet, coil, and kerosene-based magnetic fluid. First, the structural properties of insect wings are studied through measurements of certain morphological parameters. Secondly, the novel type of microwind energy converter is constructed. Thirdly, the power generation characteristics of the magnetic fluid microdevice using insect wings are examined. It is found that the output power is roughly proportional to the cube of the airflow velocity.

  17. Bacterial strategies to overcome insect defences.

    PubMed

    Vallet-Gely, Isabelle; Lemaitre, Bruno; Boccard, Frédéric

    2008-04-01

    Recent genetic and molecular analyses have revealed how several strategies enable bacteria to persist and overcome insect immune defences. Genetic and genomic tools that can be used with Drosophila melanogaster have enabled the characterization of the pathways that are used by insects to detect bacterial invaders and combat infection. Conservation of bacterial virulence factors and insect immune repertoires indicates that there are common strategies of host invasion and pathogen eradication. Long-term interactions of bacteria with insects might ensure efficient dissemination of pathogens to other hosts, including humans. PMID:18327270

  18. Insect Flight: Aerodynamics, Efficiency, and Evolution

    NASA Astrophysics Data System (ADS)

    Wang, Z. Jane

    2007-11-01

    Insects, like birds and fish, locomote via interactions between fluids and flapping wings. Their motion is governed by the Navier-Stokes equation coupled to moving boundaries. In this talk, I will first describe how dragonflies fly: their wing motions and the flows and forces they generate. I will then consider insects in several species and discuss three questions: 1) Is insect flight optimal? 2) How does the efficiency of flapping flight compare to classical fixed-wing flight? 3) How might aerodynamic effects have influenced the evolution of insect flight?

  19. Insect Seminal Fluid Proteins: Identification and Function

    PubMed Central

    Avila, Frank W.; Sirot, Laura K.; LaFlamme, Brooke A.; Rubinstein, C. Dustin; Wolfner, Mariana F.

    2014-01-01

    Seminal fluid proteins (SFPs) produced in reproductive tract tissues of male insects and transferred to females during mating induce numerous physiological and behavioral post-mating changes in females. These changes include decreasing receptivity to re-mating, affecting sperm storage parameters, increasing egg production, modulating sperm competition, feeding behaviors, and mating plug formation. In addition, SFPs also have anti-microbial functions and induce expression of anti-microbial peptides in at least some insects. Here, we review recent identification of insect SFPs and discuss the multiple roles these proteins play in the post-mating processes of female insects. PMID:20868282

  20. The use and manipulation of insect reproductive molecules for controlling insect populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use and manipulation of insect reproductive molecules, and the genes that encode them, provides a variety of methods to control insect fertility and thus a means of population control for insect pests. Towards this end, we first studied the yolk polypeptide gene from the caribfly, Anastrepha su...

  1. Laser- based Insect Tracker (LIT)

    NASA Astrophysics Data System (ADS)

    Mesquita, Leonardo; Sinha, Shiva; van Steveninck, Rob De Ruyter

    2011-03-01

    Insects are excellent model systems for studying learning and behavior, and the potential for genetic manipulation makes the fruitfly especially attractive. Many aspects of fruitfly behavior have been studied through video based tracking methods. However, to our knowledge no current system incorporates signals for behavioral conditioning in freely moving flies. We introduce a non-video based method that enables tracking of single insects over large volumes (> 8000cm3 at high spatial (<1mm) and temporal (<1ms) resolution for extended periods (>1 hour). The system uses a set of moveable mirrors that steer a tracking laser beam. Tracking is based on feedback from a four-quadrant sensor, sampling the beam after it bounces back from a retro reflector. Through the same mirrors we couple a high speed camera for flight dynamics analysis and an IR laser for aversive heat conditioning. Such heat shocks, combined with visual stimuli projected on a screen surrounding the flight arena, enable studies of learning and memory. By sampling the long term statistics of behavior, the system augments quantitative studies of behavioral phenotypes. Preliminary results of such studies will be presented.

  2. Smads and insect hemimetabolan metamorphosis.

    PubMed

    Santos, Carolina G; Fernandez-Nicolas, Ana; Belles, Xavier

    2016-09-01

    In contrast with Drosophila melanogaster, practically nothing is known about the involvement of the TGF-β signaling pathway in the metamorphosis of hemimetabolan insects. To partially fill this gap, we have studied the role of Smad factors in the metamorphosis of the German cockroach, Blattella germanica. In D. melanogaster, Mad is the canonical R-Smad of the BMP branch of the TGF-β signaling pathway, Smox is the canonical R-Smad of the TGF-β/Activin branch and Medea participates in both branches. In insects, metamorphosis is regulated by the MEKRE93 pathway, which starts with juvenile hormone (JH), whose signal is transduced by Methoprene-tolerant (Met), which stimulates the expression of Krüppel homolog 1 (Kr-h1) that acts to repress E93, the metamorphosis trigger. In B. germanica, metamorphosis is determined at the beginning of the sixth (final) nymphal instar (N6), when JH production ceases, the expression of Kr-h1 declines, and the transcription of E93 begins to increase. The RNAi of Mad, Smox and Medea in N6 of B. germanica reveals that the BMP branch of the TGF-β signaling pathway regulates adult ecdysis and wing extension, mainly through regulating the expression of bursicon, whereas the TGF-β/Activin branch contributes to increasing E93 and decreasing Kr-h1 at the beginning of N6, crucial for triggering adult morphogenesis, as well as to regulating the imaginal molt timing. PMID:27452629

  3. Diversity in Protein Glycosylation among Insect Species

    PubMed Central

    Vandenborre, Gianni; Smagghe, Guy; Ghesquière, Bart; Menschaert, Gerben; Nagender Rao, Rameshwaram; Gevaert, Kris; Van Damme, Els J. M.

    2011-01-01

    Background A very common protein modification in multicellular organisms is protein glycosylation or the addition of carbohydrate structures to the peptide backbone. Although the Class of the Insecta is the largest animal taxon on Earth, almost all information concerning glycosylation in insects is derived from studies with only one species, namely the fruit fly Drosophila melanogaster. Methodology/Principal Findings In this report, the differences in glycoproteomes between insects belonging to several economically important insect orders were studied. Using GNA (Galanthus nivalis agglutinin) affinity chromatography, different sets of glycoproteins with mannosyl-containing glycan structures were purified from the flour beetle (Tribolium castaneum), the silkworm (Bombyx mori), the honeybee (Apis mellifera), the fruit fly (D. melanogaster) and the pea aphid (Acyrthosiphon pisum). To identify and characterize the purified glycoproteins, LC-MS/MS analysis was performed. For all insect species, it was demonstrated that glycoproteins were related to a broad range of biological processes and molecular functions. Moreover, the majority of glycoproteins retained on the GNA column were unique to one particular insect species and only a few glycoproteins were present in the five different glycoprotein sets. Furthermore, these data support the hypothesis that insect glycoproteins can be decorated with mannosylated O-glycans. Conclusions/Significance The results presented here demonstrate that oligomannose N-glycosylation events are highly specific depending on the insect species. In addition, we also demonstrated that protein O-mannosylation in insect species may occur more frequently than currently believed. PMID:21373189

  4. Testing mechanistic models of growth in insects.

    PubMed

    Maino, James L; Kearney, Michael R

    2015-11-22

    Insects are typified by their small size, large numbers, impressive reproductive output and rapid growth. However, insect growth is not simply rapid; rather, insects follow a qualitatively distinct trajectory to many other animals. Here we present a mechanistic growth model for insects and show that increasing specific assimilation during the growth phase can explain the near-exponential growth trajectory of insects. The presented model is tested against growth data on 50 insects, and compared against other mechanistic growth models. Unlike the other mechanistic models, our growth model predicts energy reserves per biomass to increase with age, which implies a higher production efficiency and energy density of biomass in later instars. These predictions are tested against data compiled from the literature whereby it is confirmed that insects increase their production efficiency (by 24 percentage points) and energy density (by 4 J mg(-1)) between hatching and the attainment of full size. The model suggests that insects achieve greater production efficiencies and enhanced growth rates by increasing specific assimilation and increasing energy reserves per biomass, which are less costly to maintain than structural biomass. Our findings illustrate how the explanatory and predictive power of mechanistic growth models comes from their grounding in underlying biological processes. PMID:26609084

  5. Estimating Aquatic Insect Populations. Introduction to Sampling.

    ERIC Educational Resources Information Center

    Chihuahuan Desert Research Inst., Alpine, TX.

    This booklet introduces high school and junior high school students to the major groups of aquatic insects and to population sampling techniques. Chapter 1 consists of a short field guide which can be used to identify five separate orders of aquatic insects: odonata (dragonflies and damselflies); ephemeroptera (mayflies); diptera (true flies);…

  6. Applications of genome editing in insects.

    PubMed

    Reid, William; O'Brochta, David A

    2016-02-01

    Insect genome editing was first reported 1991 in Drosophila melanogaster but the technology used was not portable to other species. Not until the recent development of facile, engineered DNA endonuclease systems has gene editing become widely available to insect scientists. Most applications in insects to date have been technical in nature but this is rapidly changing. Functional genomics and genetics-based insect control efforts will be major beneficiaries of the application of contemporary gene editing technologies. Engineered endonucleases like Cas9 make it possible to create powerful and effective gene drive systems that could be used to reduce or even eradicate specific insect populations. 'Best practices' for using Cas9-based editing are beginning to emerge making it easier and more effective to design and use but gene editing technologies still require traditional means of delivery in order to introduce them into somatic and germ cells of insects-microinjection of developing embryos. This constrains the use of these technologies by insect scientists. Insects created using editing technologies challenge existing governmental regulatory structures designed to manage genetically modified organisms. PMID:27436552

  7. Potential applications of insect symbionts in biotechnology.

    PubMed

    Berasategui, Aileen; Shukla, Shantanu; Salem, Hassan; Kaltenpoth, Martin

    2016-02-01

    Symbiotic interactions between insects and microorganisms are widespread in nature and are often the source of ecological innovations. In addition to supplementing their host with essential nutrients, microbial symbionts can produce enzymes that help degrade their food source as well as small molecules that defend against pathogens, parasites, and predators. As such, the study of insect ecology and symbiosis represents an important source of chemical compounds and enzymes with potential biotechnological value. In addition, the knowledge on insect symbiosis can provide novel avenues for the control of agricultural pest insects and vectors of human diseases, through targeted manipulation of the symbionts or the host-symbiont associations. Here, we discuss different insect-microbe interactions that can be exploited for insect pest and human disease control, as well as in human medicine and industrial processes. Our aim is to raise awareness that insect symbionts can be interesting sources of biotechnological applications and that knowledge on insect ecology can guide targeted efforts to discover microorganisms of applied value. PMID:26659224

  8. Towards the elements of successful insect RNAi

    PubMed Central

    Scott, Jeffrey G.; Michel, Kristin; Bartholomay, Lyric; Siegfried, Blair D.; Hunter, Wayne B.; Smagghe, Guy; Zhu, Kun Yan; Douglas, Angela E.

    2013-01-01

    RNA interference (RNAi), the sequence-specific suppression of gene expression, offers great opportunities for insect science, especially to analyze gene function, manage pest populations, and reduce disease pathogens. The accumulating body of literature on insect RNAi has revealed that the efficiency of RNAi varies between different species, the mode of RNAi delivery, and the genes being targeted. There is also variation in the duration of transcript suppression. At present, we have a limited capacity to predict the ideal experimental strategy for RNAi of a particular gene/insect because of our incomplete understanding of whether and how the RNAi signal is amplified and spread among insect cells. Consequently, development of the optimal RNAi protocols is a highly empirical process. This limitation can be relieved by systematic analysis of the molecular physiological basis of RNAi mechanisms in insects. An enhanced conceptual understanding of RNAi function in insects will facilitate the application of RNAi for dissection of gene function, and to fast-track the application of RNAi to both control pests and develop effective methods to protect beneficial insects and non-insect arthropods, particularly the honey bee (Apis mellifera) and cultured Pacific white shrimp (Litopenaeus vannamei) from viral and parasitic diseases. PMID:24041495

  9. Applications of genome editing in insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect genome editing was first reported 1991 in Drosophila melanogaster but the technology used was not portable to other species. Not until the recent development of facile, engineered DNA endonuclease systems has gene editing become widely available to insect scientists. Most applications in inse...

  10. What Do Elementary Students Know about Insects?

    ERIC Educational Resources Information Center

    Barrow, Lloyd H.

    2002-01-01

    Presents an interview-based study of (n=56) elementary school students. Determines students' understanding about insect characteristics, life cycles, environmental conditions, and impact on humans. Suggests building units of instruction based on students' personal questions about insects. (Contains 16 references.) (Author/YDS)

  11. Eicosanoids: Progress Toward Manipulating Insect Immunity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect immunity is exclusively innate, lacking the antibody-based adaptive immunity of vertebrates. Innate immunity is a naturally occurring, non-specific system that does not require previous infectious experience. In this essay I describe insect immunity and review the roles of prostaglandins an...

  12. Permian insect wing from antarctic sentinel mountains.

    PubMed

    Tasch, P; Riek, E F

    1969-06-27

    A homopterous insect wing was found in micaceous graywacke from the Polarstar Formation, Sentinel Mountains. The unusual venation is reminiscent of family Stenoviciidae known from the Permian and Triassic of Eastern Australia and elsewhere. This first documented account of Paleozoic insects in Antarctica bears on drift questions. PMID:17748532

  13. Anti-viral Responses in Insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although the study of anti-viral responses in insects has lagged behind studies of responses to other types of pathogens, progress has begun to rapidly accelerate over the past few years. Insects are subject to infection by many different kinds of DNA and RNA viruses. These include viruses that ar...

  14. Polydnaviruses: Roles in insect pathology and applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the more unusual groups of insect pathogens consists of members of the family Polydnaviridae, DNA insect viruses that live in mutual symbioses with their associated parasitoid wasp (Hymentoptera) carriers until they are injected into specific Lepidopteran hosts. Once inside this secondary hos...

  15. Insects and Spiders. Environmental Education Curriculum.

    ERIC Educational Resources Information Center

    Topeka Public Schools, KS.

    This unit is designed to provide information on insects and spiders that special education students are capable of understanding. The activities are aimed at level 2 and level 3 educable mentally retarded classes. There are four topics: (1) Characteristics and Life Cycles of Insects; (2) Characteristics of Spiders; (3) Habitats and Food Sources of…

  16. Eric Carle-Inspired Insect Collages.

    ERIC Educational Resources Information Center

    Palamountain, Eileen; Turner, Kim

    2000-01-01

    Describes a lesson in which students create collage insects inspired by the work of Eric Carle (The Very Hungry Caterpillar). Connects art, language arts, and science. Discusses how students make paper to use as the collage material and how students create the insects. (CMK)

  17. Genomics of Insect-Soybean Interactions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The dissection of plant-insect interactions has lagged behind that of interactions between plants and other types of pests. Insect pests interact with plants in a variety of ways, ranging from piercing and sucking of phloem to consumption of leaves and other tissues. Hence, a wide range of genetic m...

  18. Beneficial Insects and Spiders of Alaska

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development of integrated pest management programs is dependent on the availability of biological information on beneficial insects and natural enemies of agricultural pests. This cooperative effort between ARS and UAF represents the first manual on beneficial insects and natural enemies of pest...

  19. Secondary succession: insect-plant relationships

    SciTech Connect

    Brown, V.K.

    1984-12-01

    Botanists have dominated the study of secondary succession, and as a result, models and theories have focused on plants. Recent work, however, has revealed several complex relationships between plants and insects during succession, including adaptations of life-cycle strategies. Furthermore, insect herbivores play a key role in the course and rate of plant succession.

  20. VIRAL DISEASES OF INVERTEBRATES OTHER THAN INSECTS

    EPA Science Inventory

    Thirteen examples of virus or viruslike related pathoses in non-insect invertebrates are described. From consideration of these examples, it becomes obvious that detailed descriptions of pathogenesis of virus diseases in non-insect invertebrates has not kept pace with the frequen...

  1. Perspectives on the state of insect transgenics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic transformation is a critical component to the fundamental genetic analysis of insect species, and holds great promise for establishing strains that improve population control and behavior for practical application. This is especially so for insects that are disease vectors, many of which a...

  2. Scope and Basic Principles of Insect Pathology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insects are the dominant animals in the world with more than one million described species. The vast majority of insects are innocuous or beneficial to humans, but a small percentage are pests that require a significant amount of our time, effort and funds to reduce their negative effects on food pr...

  3. CHARACTERIZATION OF MICROBIAL GUT FLORA OF HETEROPTEROUS INSECTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many insects harbor a robust complement of prokaryotes in their alimentary canals. These microorganisms may facilitate nutrient availability and utilization, detoxification of environmental toxins, or play other important roles in the insect's life history. Understanding insect-microorganism inter...

  4. Multiorganismal Insects: Diversity and Function of Resident Microorganisms

    PubMed Central

    Douglas, Angela E.

    2015-01-01

    All insects are colonized by microorganisms on the insect exoskeleton, in the gut and hemocoel, and within insect cells. The insect microbiota is generally different from microorganisms in the external environment, including ingested food. Specifically, certain microbial taxa are favored by the conditions and resources in the insect habitat, by their tolerance of insect immunity, and by specific mechanisms for their transmission. The resident microorganisms can promote insect fitness by contributing to nutrition, especially by providing essential amino acids, B vitamins, and, for fungal partners, sterols. Some microorganisms protect their insect hosts against pathogens, parasitoids, and other parasites by synthesizing specific toxins or modifying the insect immune system. Priorities for future research include elucidation of microbial contributions to detoxification, especially of plant allelochemicals in phytophagous insects, and resistance to pathogens; as well as their role in among-insect communication; and the potential value of manipulation of the microbiota to control insect pests. PMID:25341109

  5. Symbiont-mediated functions in insect hosts

    PubMed Central

    Su, Qi; Zhou, Xiaomao; Zhang, Youjun

    2013-01-01

    The bacterial endosymbionts occur in a diverse array of insect species and are usually rely within the vertical transmission from mothers to offspring. In addition to primary symbionts, plant sap-sucking insects may also harbor several diverse secondary symbionts. Bacterial symbionts play a prominent role in insect nutritional ecology by aiding in digestion of food or supplementing nutrients that insect hosts can’t obtain sufficient amounts from a restricted diet of plant phloem. Currently, several other ecologically relevant traits mediated by endosymbionts are being investigated, including defense toward pathogens and parasites, adaption to environment, influences on insect-plant interactions, and impact of population dynamics. Here, we review recent theoretical predictions and experimental observations of these traits mediated by endosymbionts and suggest that clarifying the roles of symbiotic microbes may be important to offer insights for ameliorating pest invasiveness or impact. PMID:23710278

  6. A call to insect scientists: Challenges and opportunities of managing insect communities under climate change

    USGS Publications Warehouse

    Hellmann, Jessica J.; Grundel, Ralph; Hoving, Chris; Schuurman, Gregor W.

    2016-01-01

    As climate change moves insect systems into uncharted territory, more knowledge about insect dynamics and the factors that drive them could enable us to better manage and conserve insect communities. Climate change may also require us revisit insect management goals and strategies and lead to a new kind of scientific engagement in management decision-making. Here we make five key points about the role of insect science in aiding and crafting management decisions, and we illustrate those points with the monarch butterfly and the Karner blue butterfly, two species undergoing considerable change and facing new management dilemmas. Insect biology has a strong history of engagement in applied problems, and as the impacts of climate change increase, a reimagined ethic of entomology in service of broader society may emerge. We hope to motivate insect biologists to contribute time and effort toward solving the challenges of climate change.

  7. An Automated Flying-Insect-Detection System

    NASA Technical Reports Server (NTRS)

    Vann, Timi; Andrews, Jane C.; Howell, Dane; Ryan, Robert

    2005-01-01

    An automated flying-insect-detection system (AFIDS) was developed as a proof-of-concept instrument for real-time detection and identification of flying insects. This type of system has use in public health and homeland security decision support, agriculture and military pest management, and/or entomological research. Insects are first lured into the AFIDS integrated sphere by insect attractants. Once inside the sphere, the insect's wing beats cause alterations in light intensity that is detected by a photoelectric sensor. Following detection, the insects are encouraged (with the use of a small fan) to move out of the sphere and into a designated insect trap where they are held for taxonomic identification or serological testing. The acquired electronic wing beat signatures are preprocessed (Fourier transformed) in real-time to display a periodic signal. These signals are sent to the end user where they are graphically displayed. All AFIDS data are pre-processed in the field with the use of a laptop computer equipped with LABVIEW. The AFIDS software can be programmed to run continuously or at specific time intervals when insects are prevalent. A special DC-restored transimpedance amplifier reduces the contributions of low-frequency background light signals, and affords approximately two orders of magnitude greater AC gain than conventional amplifiers. This greatly increases the signal-to-noise ratio and enables the detection of small changes in light intensity. The AFIDS light source consists of high-intensity Al GaInP light-emitting diodes (LEDs). The AFIDS circuitry minimizes brightness fluctuations in the LEDs and when integrated with an integrating sphere, creates a diffuse uniform light field. The insect wing beats isotropically scatter the diffuse light in the sphere and create wing beat signatures that are detected by the sensor. This configuration minimizes variations in signal associated with insect flight orientation.

  8. Exaggerated trait growth in insects.

    PubMed

    Lavine, Laura; Gotoh, Hiroki; Brent, Colin S; Dworkin, Ian; Emlen, Douglas J

    2015-01-01

    Animal structures occasionally attain extreme proportions, eclipsing in size the surrounding body parts. We review insect examples of exaggerated traits, such as the mandibles of stag beetles (Lucanidae), the claspers of praying mantids (Mantidae), the elongated hindlimbs of grasshoppers (Orthoptera: Caelifera), and the giant heads of soldier ants (Formicidae) and termites (Isoptera). Developmentally, disproportionate growth can arise through trait-specific modifications to the activity of at least four pathways: the sex determination pathway, the appendage patterning pathway, the insulin/IGF signaling pathway, and the juvenile hormone/ecdysteroid pathway. Although most exaggerated traits have not been studied mechanistically, it is already apparent that distinct developmental mechanisms underlie the evolution of the different types of exaggerated traits. We suggest this reflects the nature of selection in each instance, revealing an exciting link between mechanism, form, and function. We use this information to make explicit predictions for the types of regulatory pathways likely to underlie each type of exaggerated trait. PMID:25341090

  9. The kallikrein-kinin system in experimental Chagas disease: a paradigm to investigate the impact of inflammatory edema on GPCR-mediated pathways of host cell invasion by Trypanosoma cruzi

    PubMed Central

    Scharfstein, Julio; Andrade, Daniele; Svensjö, Erik; Oliveira, Ana Carolina; Nascimento, Clarissa R.

    2013-01-01

    Chronic chagasic myocarditis (CCM) depends on Trypanosoma cruzi persistence in the myocardium. Studies of the proteolytic mechanisms governing host/parasite balance in peripheral sites of T. cruzi infection revealed that tissue culture trypomastigotes (TCTs) elicit inflammatory edema and stimulate protective type-1 effector T cells through the activation of the kallikrein-kinin system. Molecular studies linked the proinflammatory phenotype of Dm28c TCTs to the synergistic activities of tGPI, a lipid anchor that functions as a Toll-like receptor 2 (TLR2) ligand, and cruzipain, a kinin-releasing cysteine protease. Analysis of the dynamics of inflammation revealed that TCTs activate innate sentinel cells via TLR2, releasing CXC chemokines, which in turn evoke neutrophil/CXCR2-dependent extravasation of plasma proteins, including high molecular weight kininogen (HK), in parasite-laden tissues. Further downstream, TCTs process surface bound HK, liberating lysyl-BK (LBK), which then propagates inflammatory edema via signaling of endothelial G-protein-coupled bradykinin B2 receptors (BK2R). Dm28 TCTs take advantage of the transient availability of infection-promoting peptides (e.g., bradykinin and endothelins) in inflamed tissues to invade cardiovascular cells via interdependent signaling of BKRs and endothelin receptors (ETRs). Herein we present a space-filling model whereby ceramide-enriched endocytic vesicles generated by the sphingomyelinase pathway might incorporate BK2R and ETRs, which then trigger Ca2+-driven responses that optimize the housekeeping mechanism of plasma membrane repair from cell wounding. The hypothesis predicts that the NF-κB-inducible BKR (BK1R) may integrate the multimolecular signaling platforms forged by ceramide rafts, as the chronic myocarditis progresses. Exploited as gateways for parasite invasion, BK2R, BK1R, ETAR, ETBR, and other G protein-coupled receptor partners may enable persistent myocardial parasitism in the edematous tissues at

  10. The earliest known holometabolous insects.

    PubMed

    Nel, André; Roques, Patrick; Nel, Patricia; Prokin, Alexander A; Bourgoin, Thierry; Prokop, Jakub; Szwedo, Jacek; Azar, Dany; Desutter-Grandcolas, Laure; Wappler, Torsten; Garrouste, Romain; Coty, David; Huang, Diying; Engel, Michael S; Kirejtshuk, Alexander G

    2013-11-14

    The Eumetabola (Endopterygota (also known as Holometabola) plus Paraneoptera) have the highest number of species of any clade, and greatly contribute to animal species biodiversity. The palaeoecological circumstances that favoured their emergence and success remain an intriguing question. Recent molecular phylogenetic analyses have suggested a wide range of dates for the initial appearance of the Holometabola, from the Middle Devonian epoch (391 million years (Myr) ago) to the Late Pennsylvanian epoch (311 Myr ago), and Hemiptera (310 Myr ago). Palaeoenvironments greatly changed over these periods, with global cooling and increasing complexity of green forests. The Pennsylvanian-period crown-eumetabolan fossil record remains notably incomplete, particularly as several fossils have been erroneously considered to be stem Holometabola (Supplementary Information); the earliest definitive beetles are from the start of the Permian period. The emergence of the hymenopterids, sister group to other Holometabola, is dated between 350 and 309 Myr ago, incongruent with their current earliest record (Middle Triassic epoch). Here we describe five fossils--a Gzhelian-age stem coleopterid, a holometabolous larva of uncertain ordinal affinity, a stem hymenopterid, and early Hemiptera and Psocodea, all from the Moscovian age--and reveal a notable penecontemporaneous breadth of early eumetabolan insects. These discoveries are more congruent with current hypotheses of clade divergence. Eumetabola experienced episodes of diversification during the Bashkirian-Moscovian and the Kasimovian-Gzhelian ages. This cladogenetic activity is perhaps related to notable episodes of drying resulting from glaciations, leading to the eventual demise in Euramerica of coal-swamp ecosystems, evidenced by floral turnover during this interval. These ancient species were of very small size, living in the shadow of Palaeozoic-era 'giant' insects. Although these discoveries reveal unexpected Pennsylvanian

  11. Energy scavenging from insect flight

    NASA Astrophysics Data System (ADS)

    Erkan Aktakka, Ethem; Kim, Hanseup; Najafi, Khalil

    2011-09-01

    This paper reports the design, fabrication and testing of an energy scavenger that generates power from the wing motion of a Green June Beetle (Cotinis nitida) during its tethered flight. The generator utilizes non-resonant piezoelectric bimorphs operated in the d31 bending mode to convert mechanical vibrations of a beetle into electrical output. The available deflection, force, and power output from oscillatory movements at different locations on a beetle are measured with a meso-scale piezoelectric beam. This way, the optimum location to scavenge energy is determined, and up to ~115 µW total power is generated from body movements. Two initial generator prototypes were fabricated, mounted on a beetle, and harvested 11.5 and 7.5 µW in device volumes of 11.0 and 5.6 mm3, respectively, from 85 to 100 Hz wing strokes during the beetle's tethered flight. A spiral generator was designed to maximize the power output by employing a compliant structure in a limited area. The necessary technology needed to fabricate this prototype was developed, including a process to machine high-aspect ratio devices from bulk piezoelectric substrates with minimum damage to the material using a femto-second laser. The fabricated lightweight spiral generators produced 18.5-22.5 µW on a bench-top test setup mimicking beetles' wing strokes. Placing two generators (one on each wing) can result in more than 45 µW of power per insect. A direct connection between the generator and the flight muscles of the insect is expected to increase the final power output by one order of magnitude.

  12. Resilience in social insect infrastructure systems

    PubMed Central

    2016-01-01

    Both human and insect societies depend on complex and highly coordinated infrastructure systems, such as communication networks, supply chains and transportation networks. Like human-designed infrastructure systems, those of social insects are regularly subject to disruptions such as natural disasters, blockages or breaks in the transportation network, fluctuations in supply and/or demand, outbreaks of disease and loss of individuals. Unlike human-designed systems, there is no deliberate planning or centralized control system; rather, individual insects make simple decisions based on local information. How do these highly decentralized, leaderless systems deal with disruption? What factors make a social insect system resilient, and which factors lead to its collapse? In this review, we bring together literature on resilience in three key social insect infrastructure systems: transportation networks, supply chains and communication networks. We describe how systems differentially invest in three pathways to resilience: resistance, redirection or reconstruction. We suggest that investment in particular resistance pathways is related to the severity and frequency of disturbance. In the final section, we lay out a prospectus for future research. Human infrastructure networks are rapidly becoming decentralized and interconnected; indeed, more like social insect infrastructures. Human infrastructure management might therefore learn from social insect researchers, who can in turn make use of the mature analytical and simulation tools developed for the study of human infrastructure resilience. PMID:26962030

  13. New light shed on the oldest insect.

    PubMed

    Engel, Michael S; Grimaldi, David A

    2004-02-12

    Insects are the most diverse lineage of all life in numbers of species, and ecologically they dominate terrestrial ecosystems. However, how and when this immense radiation of animals originated is unclear. Only a few fossils provide insight into the earliest stages of insect evolution, and among them are specimens in chert from Rhynie, Scotland's Old Red Sandstone (Pragian; about 396-407 million years ago), which is only slightly younger than formations harbouring the earliest terrestrial faunas. The most well-known animal from Rhynie is the springtail Rhyniella praecursor (Entognatha; Collembola), long considered to be the oldest hexapod. For true insects (Ectognatha), the oldest records are two apparent wingless insects from later in the Devonian period of North America. Here we show, however, that a fragmentary fossil from Rhynie, Rhyniognatha hirsti, is not only the earliest true insect but may be relatively derived within basal Ectognatha. In fact, Rhyniognatha has derived characters shared with winged insects, suggesting that the origin of wings may have been earlier than previously believed. Regardless, Rhyniognatha indicates that insects originated in the Silurian period and were members of some of the earliest terrestrial faunas. PMID:14961119

  14. Insect prophenoloxidase: the view beyond immunity

    PubMed Central

    Lu, Anrui; Zhang, Qiaoli; Zhang, Jie; Yang, Bing; Wu, Kai; Xie, Wei; Luan, Yun-Xia; Ling, Erjun

    2014-01-01

    Insect prophenoloxidase (PPO) is an important innate immunity protein due to its involvement in cellular and humoral defense. It belongs to a group of type-3 copper-containing proteins that occurs in almost all organisms. Insect PPO has been studied for over a century, and the PPO activation cascade is becoming clearer. The insect PPO activation pathway incorporates several important proteins, including pattern-recognition receptors (PGRP, β GRP, and C-type lectins), serine proteases, and serine protease inhibitors (serpins). Due to their complexity, PPO activation mechanisms vary among insect species. Activated phenoloxidase (PO) oxidizes phenolic molecules to produce melanin around invading pathogens and wounds. The crystal structure of Manduca sexta PPO shows that a conserved amino acid, phenylalanine (F), can block the active site pocket. During activation, this blocker must be dislodged or even cleaved at the N-terminal sequence to expose the active site pockets and allow substrates to enter. Thanks to the crystal structure of M. sexta PPO, some domains and specific amino acids that affect PPO activities have been identified. Further studies of the relationship between PPO structure and enzyme activities will provide an opportunity to examine other type-3 copper proteins, and trace when and why their various physiological functions evolved. Recent researches show that insect PPO has a relationship with neuron activity, longevity, feces melanization (phytophagous insects) and development, which suggests that it is time for us to look back on insect PPO beyond the view of immunity in this review. PMID:25071597

  15. Resilience in social insect infrastructure systems.

    PubMed

    Middleton, Eliza J T; Latty, Tanya

    2016-03-01

    Both human and insect societies depend on complex and highly coordinated infrastructure systems, such as communication networks, supply chains and transportation networks. Like human-designed infrastructure systems, those of social insects are regularly subject to disruptions such as natural disasters, blockages or breaks in the transportation network, fluctuations in supply and/or demand, outbreaks of disease and loss of individuals. Unlike human-designed systems, there is no deliberate planning or centralized control system; rather, individual insects make simple decisions based on local information. How do these highly decentralized, leaderless systems deal with disruption? What factors make a social insect system resilient, and which factors lead to its collapse? In this review, we bring together literature on resilience in three key social insect infrastructure systems: transportation networks, supply chains and communication networks. We describe how systems differentially invest in three pathways to resilience: resistance, redirection or reconstruction. We suggest that investment in particular resistance pathways is related to the severity and frequency of disturbance. In the final section, we lay out a prospectus for future research. Human infrastructure networks are rapidly becoming decentralized and interconnected; indeed, more like social insect infrastructures. Human infrastructure management might therefore learn from social insect researchers, who can in turn make use of the mature analytical and simulation tools developed for the study of human infrastructure resilience. PMID:26962030

  16. Prostaglandins and Their Receptors in Insect Biology

    PubMed Central

    Stanley, David; Kim, Yonggyun

    2011-01-01

    We treat the biological significance of prostaglandins (PGs) and their known receptors in insect biology. PGs and related eicosanoids are oxygenated derivatives of arachidonic acid (AA) and two other C20 polyunsaturated fatty acids. PGs are mostly appreciated in the context of biomedicine, but a growing body of literature indicates the biological significance of these compounds extends throughout the animal kingdom, and possibly beyond. The actions of most PGs are mediated by specific receptors. Biomedical research has discovered a great deal of knowledge about PG receptors in mammals, including their structures, pharmacology, molecular biology and cellular locations. Studies of PG receptors in insects lag behind the biomedical background, however, recent results hold the promise of accelerated research in this area. A PG receptor has been identified in a class of lepidopteran hemocytes and experimentally linked to the release of prophenoloxidase. PGs act in several crucial areas of insect biology. In reproduction, a specific PG, PGE2, releases oviposition behavior in most crickets and a few other insect species; PGs also mediate events in egg development in some species, which may represent all insects. PGs play major roles in modulating fluid secretion in Malpighian tubules, rectum and salivary glands, although, again, this has been studied in only a few insect species that may represent the Class. Insect immunity is a very complex defense system. PGs and other eicosanoids mediate a large number of immune reactions to infection and invasion. We conclude that research into PGs and their receptors in insects will lead to important advances in our understanding of insect biology. PMID:22654840

  17. An Automated Flying-Insect Detection System

    NASA Technical Reports Server (NTRS)

    Vann, Timi; Andrews, Jane C.; Howell, Dane; Ryan, Robert

    2007-01-01

    An automated flying-insect detection system (AFIDS) was developed as a proof-of-concept instrument for real-time detection and identification of flying insects. This type of system has use in public health and homeland-security decision support, agriculture and military pest management, and/or entomological research. Insects are first lured into the AFIDS integrated sphere by insect attractants. Once inside the sphere, the insect s wing beats cause alterations in light intensity that is detected by a photoelectric sensor. Following detection, the insects are encouraged (with the use of a small fan) to move out of the sphere and into a designated insect trap where they are held for taxonomic identification or serological testing. The acquired electronic wing-beat signatures are preprocessed (Fourier transformed) in real time to display a periodic signal. These signals are sent to the end user where they are graphically. All AFIDS data are preprocessed in the field with the use of a laptop computer equipped with LabVIEW. The AFIDS software can be programmed to run continuously or at specific time intervals when insects are prevalent. A special DC-restored transimpedance amplifier reduces the contributions of low-frequency background light signals, and affords approximately two orders of magnitude greater AC gain than conventional amplifiers. This greatly increases the signal-to-noise ratio and enables the detection of small changes in light intensity. The AFIDS light source consists of high-intensity Al-GaInP light-emitting diodes (LEDs). The AFIDS circuitry minimizes brightness fluctuations in the LEDs and when integrated with an integrating sphere, creates a diffuse uniform light field. The insect wing beats isotropically scatter the diffuse light in the sphere and create wing-beat signatures that are detected by the sensor. This configuration minimizes variations in signal associated with insect flight orientation. Preliminary data indicate that AFIDS has

  18. Microbiome influences on insect host vector competence

    PubMed Central

    Weiss, Brian

    2011-01-01

    Insect symbioses lack the complexity and diversity of those associated with higher eukaryotic hosts. Symbiotic microbiomes are beneficial to their insect hosts in many ways, including dietary supplementation, tolerance to environmental perturbations and maintenance and/or enhancement of host immune system homeostasis. Recent studies have also highlighted the importance of the microbiome in the context of host pathogen transmission processes. Here we provide an overview of the relationship between insect disease vectors, such as tsetse flies and mosquitoes, and their associated microbiome. Several mechanisms are discussed through which symbiotic microbes may influence their host’s ability to transmit pathogens, as well as potential disease control strategies that harness symbiotic microbes to reduce pathogen transmission through an insect vector. PMID:21697014

  19. Selectivity of odorant receptors in insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect olfactory receptors (ORs) detect chemical signals, shape neuronal physiology and regulate behavior. Although ORs have been categorized as generalists and specialists based on their ligand spectrum, both electrophysiological studies and recent pharmacological investigations show that ORs spec...

  20. Insect food aiming at Mars emigration

    NASA Astrophysics Data System (ADS)

    Katayama, Naomi; Yamashita, Masamichi; Hashimoto, Hirofumi; Nagasaka, Sanako; Kuwayama, Akemi; Sofue, Megumi

    2012-07-01

    We study insect food aiming at Mars emigration.In space agriculture, insect is the important creature which we cannot miss.It is necessary for the pollination of the plant, and it is rich to protein and lipid as food.I reported that silkworm is an insect necessary for astroponics in particular last time.We make clothes using silk thread, and the pupa becomes the food.In addition, the clothes can make food as protein when we need not to use it. The bee is a very important insect in the space agriculture,too.We examined nutrition of silkworm, bee, grasshopper, snail and the white ant which are necessary for Mars emigration.We will introduce of good balance space foods.We will report many meal menu for Mars emigration.

  1. Symbiont-mediated RNA interference in insects

    PubMed Central

    Whitten, Miranda M. A.; Facey, Paul D.; Del Sol, Ricardo; Fernández-Martínez, Lorena T.; Evans, Meirwyn C.; Mitchell, Jacob J.; Bodger, Owen G.

    2016-01-01

    RNA interference (RNAi) methods for insects are often limited by problems with double-stranded (ds) RNA delivery, which restricts reverse genetics studies and the development of RNAi-based biocides. We therefore delegated to insect symbiotic bacteria the task of: (i) constitutive dsRNA synthesis and (ii) trauma-free delivery. RNaseIII-deficient, dsRNA-expressing bacterial strains were created from the symbionts of two very diverse pest species: a long-lived blood-sucking bug, Rhodnius prolixus, and a short-lived globally invasive polyphagous agricultural pest, western flower thrips (Frankliniella occidentalis). When ingested, the manipulated bacteria colonized the insects, successfully competed with the wild-type microflora, and sustainably mediated systemic knockdown phenotypes that were horizontally transmissible. This represents a significant advance in the ability to deliver RNAi, potentially to a large range of non-model insects. PMID:26911963

  2. How to Find Insects Weathering the Winter.

    ERIC Educational Resources Information Center

    Brody, Jane

    1979-01-01

    Discusses how and where to find insects and other invertebrates in winter, as well as how to collect samples in order to watch those animals reappear in spring. Includes crickets, honey bees, mosquitoes, house flies, and butterflies and moths. (MA)

  3. FAQ: Insect Repellent Use and Safety

    MedlinePlus

    ... repellents? Always follow the recommendations appearing on the product label. EPA recommends the following when using insect repellents: ... skin and/or clothing (as directed on the product label). Do not apply repellents under your clothing. Never ...

  4. Insect contamination protection for laminar flow surfaces

    NASA Technical Reports Server (NTRS)

    Croom, Cynthia C.; Holmes, Bruce J.

    1986-01-01

    The ability of modern aircraft surfaces to achieve laminar flow was well-accepted in recent years. Obtaining the maximum benefit of laminar flow for aircraft drag reduction requires maintaining minimum leading-edge contamination. Previously proposed insect contamination prevention methods have proved impractical due to cost, weight, or inconvenience. Past work has shown that insects will not adhere to water-wetted surfaces, but the large volumes of water required for protection rendered such a system impractical. The results of a flight experiment conducted by NASA to evaluate the performance of a porous leading-edge fluid discharge ice protection system operated as an insect contamination protections system are presented. In addition, these flights explored the environmental and atmospheric conditions most suitable for insect accumulation.

  5. Symbiont-mediated RNA interference in insects.

    PubMed

    Whitten, Miranda M A; Facey, Paul D; Del Sol, Ricardo; Fernández-Martínez, Lorena T; Evans, Meirwyn C; Mitchell, Jacob J; Bodger, Owen G; Dyson, Paul J

    2016-02-24

    RNA interference (RNAi) methods for insects are often limited by problems with double-stranded (ds) RNA delivery, which restricts reverse genetics studies and the development of RNAi-based biocides. We therefore delegated to insect symbiotic bacteria the task of: (i) constitutive dsRNA synthesis and (ii) trauma-free delivery. RNaseIII-deficient, dsRNA-expressing bacterial strains were created from the symbionts of two very diverse pest species: a long-lived blood-sucking bug, Rhodnius prolixus, and a short-lived globally invasive polyphagous agricultural pest, western flower thrips (Frankliniella occidentalis). When ingested, the manipulated bacteria colonized the insects, successfully competed with the wild-type microflora, and sustainably mediated systemic knockdown phenotypes that were horizontally transmissible. This represents a significant advance in the ability to deliver RNAi, potentially to a large range of non-model insects. PMID:26911963

  6. PRACTICAL SYNTHESES OF SELECTED INSECT PHEROMONES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Practical examples of insect pheromone synthesis, from our laboratory will be presented. Examples of key reactions in synthetic pathways include: Regiospecific epoxidation (cereal leaf beetle), kinetic vs. thermodynamic control of cycloheptanone dimethylation (Aphthona flea beetles), in situ oxida...

  7. Odorant-binding proteins in insects.

    PubMed

    Zhou, Jing-Jiang

    2010-01-01

    Our understanding of the molecular and biochemical mechanisms that mediate chemoreception in insects has been greatly improved after the discovery of olfactory and taste receptor proteins. However, after 50 years of the discovery of first insect sex pheromone from the silkmoth Bombyx mori, it is still unclear how hydrophobic compounds reach the dendrites of sensory neurons in vivo across aqueous space and interact with the sensory receptors. The presence of soluble polypeptides in high concentration in the lymph of chemosensilla still poses unanswered questions. More than two decades after their discovery and despite the wealth of structural and biochemical information available, the physiological function of odorant-binding proteins (OBPs) is not well understood. Here, I review the structural properties of different subclasses of insect OBPs and their binding to pheromones and other small ligands. Finally, I discuss current ideas and models on the role of such proteins in insect chemoreception. PMID:20831949

  8. How-to-Do-It: Insect Singularis.

    ERIC Educational Resources Information Center

    Brett, William J.

    1989-01-01

    Presents an exercise which was designed to help students read material and follow directions more appropriately when performing laboratory activities. Provides a list of materials, instructions, comments, vocabulary words, and a diagrammatical sketch of an insect. (RT)

  9. A systematic nomenclature for the insect brain.

    PubMed

    Ito, Kei; Shinomiya, Kazunori; Ito, Masayoshi; Armstrong, J Douglas; Boyan, George; Hartenstein, Volker; Harzsch, Steffen; Heisenberg, Martin; Homberg, Uwe; Jenett, Arnim; Keshishian, Haig; Restifo, Linda L; Rössler, Wolfgang; Simpson, Julie H; Strausfeld, Nicholas J; Strauss, Roland; Vosshall, Leslie B

    2014-02-19

    Despite the importance of the insect nervous system for functional and developmental neuroscience, descriptions of insect brains have suffered from a lack of uniform nomenclature. Ambiguous definitions of brain regions and fiber bundles have contributed to the variation of names used to describe the same structure. The lack of clearly determined neuropil boundaries has made it difficult to document precise locations of neuronal projections for connectomics study. To address such issues, a consortium of neurobiologists studying arthropod brains, the Insect Brain Name Working Group, has established the present hierarchical nomenclature system, using the brain of Drosophila melanogaster as the reference framework, while taking the brains of other taxa into careful consideration for maximum consistency and expandability. The following summarizes the consortium's nomenclature system and highlights examples of existing ambiguities and remedies for them. This nomenclature is intended to serve as a standard of reference for the study of the brain of Drosophila and other insects. PMID:24559671

  10. Principles of Insect Identification. MP-20.

    ERIC Educational Resources Information Center

    Lawson, Fred A.; Burkhardt, Chris C.

    This document provides information for the complete classification of members of the phylum Arthropoda. Both major and minor insect orders are discussed relative to their anatomical characteristics and importance. (CS)

  11. Genetics and Biochemistry of Insect Resistance in Maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insects are a major concern for maize production worldwide. Host plant resistance to insects involves a number of chemical and biochemical factors that limit but rarely eliminate insect damage. Most chemical and many biochemical factors involved in resistance to insects are synthesized independent...

  12. Improving Cold Storage of Insects with Dietary Changes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maintaining healthy insect colonies is costly regardless of whether those insects are for research or commercial use. To reduce cost, it is highly desirable to preserve insects at reduced temperatures for short- and long-term periods with a minimal negative impact on insect quality. Recent investi...

  13. Insect cell culture and applications to research and pest management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Building on earlier research, insect cell culture began with the successful establishment of one cell line from pupal ovarian tissue. The field has grown to the extent that now over 500 insect cell lines have been established from many insect species representing numerous insect Orders and from seve...

  14. IMp: The customizable LEGO® Pinned Insect Manipulator

    PubMed Central

    Dupont, Steen; Price, Benjamin; Blagoderov, Vladimir

    2015-01-01

    Abstract We present a pinned insect manipulator (IMp) constructed of LEGO® building bricks with two axes of movement and two axes of rotation. In addition we present three variants of the IMp to emphasise the modular design, which facilitates resizing to meet the full range of pinned insect specimens, is fully customizable, collapsible, affordable and does not require specialist tools or knowledge to assemble. PMID:25685035

  15. Intraspecific body size frequency distributions of insects.

    PubMed

    Gouws, E Jeanne; Gaston, Kevin J; Chown, Steven L

    2011-01-01

    Although interspecific body size frequency distributions are well documented for many taxa, including the insects, intraspecific body size frequency distributions (IaBSFDs) are more poorly known, and their variation among mass-based and linear estimates of size has not been widely explored. Here we provide IaBSFDs for 16 species of insects based on both mass and linear estimates and large sample sizes (n ≥ 100). In addition, we review the published IaBSFDs for insects, though doing so is complicated by their under-emphasis in the literature. The form of IaBSFDs can differ substantially between mass-based and linear measures. Nonetheless, in non-social insects they tend to be normally distributed (18 of 27 species) or in fewer instances positively skewed. Negatively skewed distributions are infrequently reported and log transformation readily removes the positive skew. Sexual size dimorphism does not generally cause bimodality in IaBSFDs. The available information on IaBSFDs in the social insects suggests that these distributions are usually positively skewed or bimodal (24 of 30 species). However, only c. 15% of ant genera are polymorphic, suggesting that normal distributions are probably more common, but less frequently investigated. Although only 57 species, representing seven of the 29 orders of insects, have been considered here, it appears that whilst IaBSFDs are usually normal, other distribution shapes can be found in several species, though most notably among the social insects. By contrast, the interspecific body size frequency distribution is typically right-skewed in insects and in most other taxa. PMID:21479214

  16. Intraspecific Body Size Frequency Distributions of Insects

    PubMed Central

    Gouws, E. Jeanne; Gaston, Kevin J.; Chown, Steven L.

    2011-01-01

    Although interspecific body size frequency distributions are well documented for many taxa, including the insects, intraspecific body size frequency distributions (IaBSFDs) are more poorly known, and their variation among mass-based and linear estimates of size has not been widely explored. Here we provide IaBSFDs for 16 species of insects based on both mass and linear estimates and large sample sizes (n≥100). In addition, we review the published IaBSFDs for insects, though doing so is complicated by their under-emphasis in the literature. The form of IaBSFDs can differ substantially between mass-based and linear measures. Nonetheless, in non-social insects they tend to be normally distributed (18 of 27 species) or in fewer instances positively skewed. Negatively skewed distributions are infrequently reported and log transformation readily removes the positive skew. Sexual size dimorphism does not generally cause bimodality in IaBSFDs. The available information on IaBSFDs in the social insects suggests that these distributions are usually positively skewed or bimodal (24 of 30 species). However, only c. 15% of ant genera are polymorphic, suggesting that normal distributions are probably more common, but less frequently investigated. Although only 57 species, representing seven of the 29 orders of insects, have been considered here, it appears that whilst IaBSFDs are usually normal, other distribution shapes can be found in several species, though most notably among the social insects. By contrast, the interspecific body size frequency distribution is typically right-skewed in insects and in most other taxa. PMID:21479214

  17. Factors affecting the sticking of insects on modified aircraft wings

    NASA Technical Reports Server (NTRS)

    Yi, O.; Chan, R.; Eiss, N. S.; Pingali, U.; Wightman, J. P.

    1988-01-01

    The adhesion of insects to aircraft wings is studied. Insects were collected in road tests in past studies and a large experimental error was introduced caused by the variability of insect flux. The presence of such errors has been detected by studying the insect distribution across an aluminum-strip covered half-cylinder mounted on the top of a car. After a nonuniform insect distribution (insect flux) was found from three road tests, a new arrangement of samples was developed. The feasibility of coating aircraft wing surfaces with polymers to reduce the number of insects sticking onto the surfaces was studied using fluorocarbon elastomers, styrene butadiene rubbers, and Teflon.

  18. Tomographic reconstruction of neopterous carboniferous insect nymphs.

    PubMed

    Garwood, Russell; Ross, Andrew; Sotty, Daniel; Chabard, Dominique; Charbonnier, Sylvain; Sutton, Mark; Withers, Philip J

    2012-01-01

    Two new polyneopteran insect nymphs from the Montceau-les-Mines Lagerstätte of France are presented. Both are preserved in three dimensions, and are imaged with the aid of X-ray micro-tomography, allowing their morphology to be recovered in unprecedented detail. One-Anebos phrixos gen. et sp. nov.-is of uncertain affinities, and preserves portions of the antennae and eyes, coupled with a heavily spined habitus. The other is a roachoid with long antennae and chewing mouthparts very similar in form to the most generalized mandibulate mouthparts of extant orthopteroid insects. Computer reconstructions reveal limbs in both specimens, allowing identification of the segments and annulation in the tarsus, while poorly developed thoracic wing pads suggest both are young instars. This work describes the morphologically best-known Palaeozoic insect nymphs, allowing a better understanding of the juveniles' palaeobiology and palaeoecology. We also consider the validity of evidence from Palaeozoic juvenile insects in wing origin theories. The study of juvenile Palaeozoic insects is currently a neglected field, yet these fossils provide direct evidence on the evolution of insect development. It is hoped this study will stimulate a renewed interest in such work. PMID:23049858

  19. Tomographic Reconstruction of Neopterous Carboniferous Insect Nymphs

    PubMed Central

    Garwood, Russell; Ross, Andrew; Sotty, Daniel; Chabard, Dominique; Charbonnier, Sylvain; Sutton, Mark; Withers, Philip J.

    2012-01-01

    Two new polyneopteran insect nymphs from the Montceau-les-Mines Lagerstätte of France are presented. Both are preserved in three dimensions, and are imaged with the aid of X-ray micro-tomography, allowing their morphology to be recovered in unprecedented detail. One–Anebos phrixos gen. et sp. nov.–is of uncertain affinities, and preserves portions of the antennae and eyes, coupled with a heavily spined habitus. The other is a roachoid with long antennae and chewing mouthparts very similar in form to the most generalized mandibulate mouthparts of extant orthopteroid insects. Computer reconstructions reveal limbs in both specimens, allowing identification of the segments and annulation in the tarsus, while poorly developed thoracic wing pads suggest both are young instars. This work describes the morphologically best-known Palaeozoic insect nymphs, allowing a better understanding of the juveniles’ palaeobiology and palaeoecology. We also consider the validity of evidence from Palaeozoic juvenile insects in wing origin theories. The study of juvenile Palaeozoic insects is currently a neglected field, yet these fossils provide direct evidence on the evolution of insect development. It is hoped this study will stimulate a renewed interest in such work. PMID:23049858

  20. Insect Pathogenic Fungi as Endophytes.

    PubMed

    Moonjely, S; Barelli, L; Bidochka, M J

    2016-01-01

    In this chapter, we explore some of the evolutionary, ecological, molecular genetics, and applied aspects of a subset of insect pathogenic fungi that also have a lifestyle as endophytes and we term endophytic insect pathogenic fungi (EIPF). We focus particularly on Metarhizium spp. and Beauveria bassiana as EIPF. The discussion of the evolution of EIPF challenges a view that these fungi were first and foremost insect pathogens that eventually evolved to colonize plants. Phylogenetic evidence shows that the lineages of EIPF are most closely related to grass endophytes that diverged c. 100MYA. We discuss the relationship between genes involved in "insect pathogenesis" and those involved in "endophytism" and provide examples of genes with potential importance in lifestyle transitions toward insect pathogenicity. That is, some genes for insect pathogenesis may have been coopted from genes involved in endophytic colonization. Other genes may be multifunctional and serve in both lifestyle capacities. The interactions of EIPF with their host plants are discussed in some detail. The genetic basis for rhizospheric competence, plant communication, and nutrient exchange is examined and we highlight, with examples, the benefits of EIPF to plants, and the potential reservoir of secondary metabolites hidden within these beneficial symbioses. PMID:27131324

  1. Linking energetics and overwintering in temperate insects.

    PubMed

    Sinclair, Brent J

    2015-12-01

    Overwintering insects cannot feed, and energy they take into winter must therefore fuel energy demands during autumn, overwintering, warm periods prior to resumption of development in spring, and subsequent activity. Insects primarily consume lipids during winter, but may also use carbohydrate and proteins as fuel. Because they are ectotherms, the metabolic rate of insects is temperature-dependent, and the curvilinear nature of the metabolic rate-temperature relationship means that warm temperatures are disproportionately important to overwinter energy use. This energy use may be reduced physiologically, by reducing the slope or elevation of the metabolic rate-temperature relationship, or because of threshold changes, such as metabolic suppression upon freezing. Insects may also choose microhabitats or life history stages that reduce the impact of overwinter energy drain. There is considerable capacity for overwinter energy drain to affect insect survival and performance both directly (via starvation) or indirectly (for example, through a trade-off with cryoprotection), but this has not been well-explored. Likewise, the impact of overwinter energy drain on growing-season performance is not well understood. I conclude that overwinter energetics provides a useful lens through which to link physiology and ecology and winter and summer in studies of insect responses to their environment. PMID:26615721

  2. 75 FR 47592 - Final Test Guideline; Product Performance of Skin-applied Insect Repellents of Insect and Other...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-06

    ..., 2007 (72 FR 32647) (FRL-8135-9), of national experts in which the revisions made in June 2006, were... AGENCY Final Test Guideline; Product Performance of Skin-applied Insect Repellents of Insect and Other... Product Performance of Skin-applied Insect Repellents of Insect and Other Arthropods Test...

  3. Tn5 as an insect gene vector.

    PubMed

    Rowan, Kathryn H; Orsetti, Jamison; Atkinson, Peter W; O'Brochta, David A

    2004-07-01

    The purpose of this study was to explore alternatives to insect-derived transposable elements as insect gene vectors with the intention of improving existing insect transgenesis methods. The mobility properties of the bacterial transposon, Tn5, were tested in mosquitoes using a transient transposable element mobility assay and by attempting to create transgenic insects. Tn5 synaptic complexes were assembled in vitro in the absence of Mg(2+) and co-injected with a target plasmid into developing yellow fever mosquito, Aedes aegypti, embryos. Target plasmids recovered from embryos a day later were screened for the presence of Tn5. Recombinants (transposition events) were found at a frequency of 1.2 x 10(-3). Some transposition events did not appear to be associated with canonical 9 bp direct duplications at the site of insertion and also were associated with either deletions or rearrangements. A Tn5 element containing the brain-specific transgene, 3 x P3DsRed, was assembled into synaptic complexes in vitro and injected into pre-blastoderm embryos of Ae. aegypti. Of the approximately 900 embryos surviving injection and developing into adults, two produced transgenic progeny. Both transgenic events involved the co-integrations of approximately five elements resulting in nested and tandem arrayed Tn5::3 x P3DsRed elements. This study extends the known host range of Tn5 to insects and makes available to insect biologists and others another eukaryotic genome-manipulation tool. The hyperactivity of synaptic complexes may be responsible for the unusual clustering of elements and managing this aspect of the element's behavior will be important in future applications of this technology to insects. PMID:15242711

  4. Quantifying the movement of multiple insects using an optical insect counter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An optical insect counter (OIC) was designed and tested. The new system integrated a line-scan camera and a vertical light sheet along with data collection and image processing software to count numbers of flying insects crossing a vertical plane defined by the light sheet. The system also allows ...

  5. Residual efficacy of the insect growth regulator pyriproxyfen for control of stored product insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The insect growth regulator pyriproxyfen is registered in the USA as an aerosol and as a surface treatment to control stored product insects. Field trials with the aerosol show that residues from an application of pyrethrin + pyriproxyfen gave residual control of the red flour beetle, Tribolium cast...

  6. Quantifying the movement of multiple insects using an optical insect counter.

    PubMed

    Hoffmann, Wesley C; Jank, Philip C; Klun, Jerome A; Fritz, Bradley K

    2010-06-01

    An optical insect counter (OIC) was designed and tested. The new system integrated a line-scan camera and a vertical light sheet along with data collection and image-processing software to count flying insects crossing a vertical plane defined by the light sheet. The system also discriminates each insect by its position along the horizontal length defined by the light sheet. The system was successfully tested with a preliminary experimental protocol for determining whether groups of flying mosquitoes preferred or avoided attractants and repellents in a flight tunnel. The OIC counted the number of mosquitoes that crossed the light sheet and recorded the horizontal position and time each insect passed through the light sheet. The system provides a straightforward and reliable method for measuring and recording spatial and temporal information for insects that pass through an established plane. PMID:20649126

  7. Naturally occurring insect growth regulators. II. Screening of insect and plant extracts as insect juvenile hormone mimics.

    PubMed

    Jacobson, M; Redfern, R E; Mills, G D

    1975-01-01

    Ethereal extracts prepared from the larvae, pupae, or eggs of 10 species of insects and from various parts of 343 species of higher plants were screened for juvenilizing effects against Tenebrio molitor and Oncopeltus fasciatus. Activity in both species was shown by an extract of the larvae of the stable fly, Stomoxys calcitrans, whereas an extract of the pupae was active in O. fasiatus only. Extracts of two plant species (Echinacea angustifolia roots and Chamaecyparis lawsoniana seeds) showed high juvenilizing activity in T. MOLITOR, AND EXtracts of five plant species (Clethra alnifolia stems, leaves, and fruits, Sassafras albidum roots and root bark, Eucalyptus camaldulensis stems and bark, Pinus rigida twigs and leaves, and Iris douglasiana roots, stems, and fruits) were highly active in O. fasciatus an extract of Tsuga canadensis leaves showed lower activity in this insect. Extracts of 16 species of plants showed high insecticidal activity (mortality) in O. fasciatus but lacked juvenilizing properties in both species of test insects. PMID:1221244

  8. Fungus-insect gall of Phlebopus portentosus.

    PubMed

    Zhang, Chun-Xia; He, Ming-Xia; Cao, Yang; Liu, Jing; Gao, Feng; Wang, Wen-Bing; Ji, Kai-Ping; Shao, Shi-Cheng; Wang, Yun

    2015-01-01

    Phlebopus portentosus is a popular edible wild mushroom found in the tropical Yunnan, China, and northern Thailand. In its natural habitats, a gall often has been found on some plant roots, around which fungal fruiting bodies are produced. The galls are different from common insect galls in that their cavity walls are not made from plant tissue but rather from the hyphae of P. portentosus. Therefore we have termed this phenomenon "fungus-insect gall". Thus far six root mealy bug species in the family Pseudococcidae that form fungus-insect galls with P. portentosus have been identified: Formicococcus polysperes, Geococcus satellitum, Planococcus minor, Pseudococcus cryptus, Paraputo banzigeri and Rastrococcus invadens. Fungus-insect galls were found on the roots of more than 21 plant species, including Delonix regia, Citrus maxima, Coffea arabica and Artocarpus heterophyllus. Greenhouse inoculation trials showed that fungus-insect galls were found on the roots of A. heterophyllus 1 mo after inoculation. The galls were subglobose to globose, fulvous when young and became dark brown at maturation. Each gall harbored one or more mealy bugs and had a chimney-like vent for ventilation and access to the gall. The cavity wall had three layers. Various shaped mealy bug wax deposits were found inside the wall. Fungal hyphae invaded the epidermis of plant roots and sometimes even the cortical cells during the late stage of gall development. The identity of the fungus inside the cavity was confirmed by molecular methods. PMID:25344264

  9. Gall insects and indirect plant defenses

    PubMed Central

    De Moraes, Consuelo M

    2008-01-01

    Many plants can defend themselves against insect herbivory by attracting natural enemies that kill feeding herbivores and limit the damage they inflict. Such “indirect defenses” can be induced by insects feeding on different plant tissues and using a variety of feeding styles. However, we have recently shown that gall-inducing insect species can avoid the indirect defenses of their host plant species and even alter volatile emissions following subsequent herbivory. One of the species we studied, Eurosta solidaginis, induces galls on goldenrod (Solidago altissima) and appears to exert a unique influence over the indirect defenses of its host plant that is not readily explained by levels of defense-related phytohormones, gall formation or resource depletion. Our evidence suggests that this gall-insect species may be able to manipulate its host plant species to avoid and/or modify its defensive responses. The results also provide insight into gall induction because the gall-insect species that we screened did not increase levels of jasmonic acid, which, in addition to triggering volatile emissions, is a powerful growth regulator that could prevent the cell growth and division that leads to gall formation. PMID:19704500

  10. Acoustic communication in insect disease vectors

    PubMed Central

    Vigoder, Felipe de Mello; Ritchie, Michael Gordon; Gibson, Gabriella; Peixoto, Alexandre Afranio

    2013-01-01

    Acoustic signalling has been extensively studied in insect species, which has led to a better understanding of sexual communication, sexual selection and modes of speciation. The significance of acoustic signals for a blood-sucking insect was first reported in the XIX century by Christopher Johnston, studying the hearing organs of mosquitoes, but has received relatively little attention in other disease vectors until recently. Acoustic signals are often associated with mating behaviour and sexual selection and changes in signalling can lead to rapid evolutionary divergence and may ultimately contribute to the process of speciation. Songs can also have implications for the success of novel methods of disease control such as determining the mating competitiveness of modified insects used for mass-release control programs. Species-specific sound “signatures” may help identify incipient species within species complexes that may be of epidemiological significance, e.g. of higher vectorial capacity, thereby enabling the application of more focussed control measures to optimise the reduction of pathogen transmission. Although the study of acoustic communication in insect vectors has been relatively limited, this review of research demonstrates their value as models for understanding both the functional and evolutionary significance of acoustic communication in insects. PMID:24473800

  11. Uncontrolled Stability in Freely Flying Insects

    NASA Astrophysics Data System (ADS)

    Melfi, James, Jr.; Wang, Z. Jane

    2015-11-01

    One of the key flight modes of a flying insect is longitudinal flight, traveling along a localized two-dimensional plane from one location to another. Past work on this topic has shown that flying insects, unless stabilized by some external stimulus, are typically unstable to a well studied pitching instability. In our work, we examine this instability in a computational study to understand whether it is possible for either evolution or an aero-vehicle designer to stabilize longitudinal flight through changes to insect morphology, kinematics, or aerodynamic quantities. A quasi-steady wingbeat averaged flapping flight model is used to describe the insect. From this model, a number of non-dimensional parameters are identified. The effect of these parameters was then quantified using linear stability analysis, applied to various translational states of the insect. Based on our understanding of these parameters, we demonstrate how to find an intrinsically stable flapping flight sequence for a dragonfly-like flapping flier in an instantaneous flapping flight model.

  12. Insect pest management in forest ecosystems

    NASA Astrophysics Data System (ADS)

    Dahlsten, Donald L.; Rowney, David L.

    1983-01-01

    Understanding the role of insects in forest ecosystems is vital to the development of environmentally and economically sound pest management strategies in forestry Most of the research on forest insects has been confined to phytophagous species associated with economically important tree species The roles of most other insects in forest environments have generally been ignored, including the natural enemies and associates of phytophagous species identified as being important In the past few years several investigations have begun to reevaluate the role of phytophagous species responsible for perturbation in forest ecosystems, and it appears that these species may be playing an important role in the primary productivity of those ecosystems Also, there is an increasing awareness that forest pest managers have been treating the symptoms and not the causes of the problems in the forest Many insect problems are associated with poor sites or sites where trees are growing poorly because of crowding As a result, there is considerable emphasis on the hazard rating of stands of trees for their susceptibility to various phytophagous insects The next step is to manipulate forest stands to make them less susceptible to forest pest complexes A thinning study in California is used as an example and shows that tree mortality in ponderosa pine ( Pinus ponderosa) attributable to the western pine beetle ( Dendroctonus brevicomis) can be reduced by commercial thinning to reduce stocking

  13. Flapping wing aerodynamics: from insects to vertebrates.

    PubMed

    Chin, Diana D; Lentink, David

    2016-04-01

    More than a million insects and approximately 11,000 vertebrates utilize flapping wings to fly. However, flapping flight has only been studied in a few of these species, so many challenges remain in understanding this form of locomotion. Five key aerodynamic mechanisms have been identified for insect flight. Among these is the leading edge vortex, which is a convergent solution to avoid stall for insects, bats and birds. The roles of the other mechanisms - added mass, clap and fling, rotational circulation and wing-wake interactions - have not yet been thoroughly studied in the context of vertebrate flight. Further challenges to understanding bat and bird flight are posed by the complex, dynamic wing morphologies of these species and the more turbulent airflow generated by their wings compared with that observed during insect flight. Nevertheless, three dimensionless numbers that combine key flow, morphological and kinematic parameters - the Reynolds number, Rossby number and advance ratio - govern flapping wing aerodynamics for both insects and vertebrates. These numbers can thus be used to organize an integrative framework for studying and comparing animal flapping flight. Here, we provide a roadmap for developing such a framework, highlighting the aerodynamic mechanisms that remain to be quantified and compared across species. Ultimately, incorporating complex flight maneuvers, environmental effects and developmental stages into this framework will also be essential to advancing our understanding of the biomechanics, movement ecology and evolution of animal flight. PMID:27030773

  14. Veins improve fracture toughness of insect wings.

    PubMed

    Dirks, Jan-Henning; Taylor, David

    2012-01-01

    During the lifetime of a flying insect, its wings are subjected to mechanical forces and deformations for millions of cycles. Defects in the micrometre thin membranes or veins may reduce the insect's flight performance. How do insects prevent crack related material failure in their wings and what role does the characteristic vein pattern play? Fracture toughness is a parameter, which characterises a material's resistance to crack propagation. Our results show that, compared to other body parts, the hind wing membrane of the migratory locust S. gregaria itself is not exceptionally tough (1.04±0.25 MPa√m). However, the cross veins increase the wing's toughness by 50% by acting as barriers to crack propagation. Using fracture mechanics, we show that the morphological spacing of most wing veins matches the critical crack length of the material (1132 µm). This finding directly demonstrates how the biomechanical properties and the morphology of locust wings are functionally correlated in locusts, providing a mechanically 'optimal' solution with high toughness and low weight. The vein pattern found in insect wings thus might inspire the design of more durable and lightweight artificial 'venous' wings for micro-air-vehicles. Using the vein spacing as indicator, our approach might also provide a basis to estimate the wing properties of endangered or extinct insect species. PMID:22927966

  15. Magnetoreception in eusocial insects: an update

    PubMed Central

    Wajnberg, Eliane; Acosta-Avalos, Daniel; Alves, Odivaldo Cambraia; de Oliveira, Jandira Ferreira; Srygley, Robert B.; Esquivel, Darci M. S.

    2010-01-01

    Behavioural experiments for magnetoreception in eusocial insects in the last decade are reviewed. Ants and bees use the geomagnetic field to orient and navigate in areas around their nests and along migratory paths. Bees show sensitivity to small changes in magnetic fields in conditioning experiments and when exiting the hive. For the first time, the magnetic properties of the nanoparticles found in eusocial insects, obtained by magnetic techniques and electron microscopy, are reviewed. Different magnetic oxide nanoparticles, ranging from superparamagnetic to multi-domain particles, were observed in all body parts, but greater relative concentrations in the abdomens and antennae of honeybees and ants have focused attention on these segments. Theoretical models for how these specific magnetosensory apparatuses function have been proposed. Neuron-rich ant antennae may be the most amenable to discovering a magnetosensor that will greatly assist research into higher order processing of magnetic information. The ferromagnetic hypothesis is believed to apply to eusocial insects, but interest in a light-sensitive mechanism is growing. The diversity of compass mechanisms in animals suggests that multiple compasses may function in insect orientation and navigation. The search for magnetic compasses will continue even after a magnetosensor is discovered in eusocial insects. PMID:20106876

  16. Unraveling navigational strategies in migratory insects

    PubMed Central

    Merlin, Christine; Heinze, Stanley; Reppert, Steven M.

    2011-01-01

    Long-distance migration is a strategy some animals use to survive a seasonally changing environment. To reach favorable grounds, migratory animals have evolved sophisticated navigational mechanisms that rely on a map and compasses. In migratory insects, the existence of a map sense (sense of position) remains poorly understood, but recent work has provided new insights into the mechanisms some compasses use for maintaining a constant bearing during long-distance navigation. The best-studied directional strategy relies on a time-compensated sun compass, used by diurnal insects, for which neural circuits have begun to be delineated. Yet, a growing body of evidence suggests that migratory insects may also rely on other compasses that use night sky cues or the Earth's magnetic field. Those mechanisms are ripe for exploration. PMID:22154565

  17. Insect societies and the social brain.

    PubMed

    Farris, Sarah M

    2016-06-01

    The 'social brain hypothesis,' the relationship between social behavior and brain size, does not apply to insects. In social insects, especially those of the Order Hymenoptera (ants, bees and wasps), sociality has not always increased individual behavioral repertoires and is associated with only subtle variation in the size of a higher brain center, the mushroom bodies. Rather than sociality, selection for novel visual behavior, perhaps spatial learning, has led to the acquisition of novel visual inputs and profound increases in mushroom body size. This occurred in nonsocial ancestors suggesting that the sensory and cognitive advantages of large mushroom bodies may be preadaptations to sociality. Adaptations of the insect mushroom bodies are more reliably associated with sensory ecology than social behavior. PMID:27436726

  18. "Qupirruit": insects and worms in Inuit traditions.

    PubMed

    Laugrand, Frédéric; Oosten, Jarich

    2010-01-01

    Although small beings such as the "qupirruit" (insects and worms) appear in many different contexts in Inuit culture, they have not received much attention from scholars. In this paper we examine the symbolism associated with these small animals. We show that their small size makes them suitable to operate on the level of the "tarniq," a miniature image of a being. We discuss how insects often connect different scales and easily transform into other beings. We first deal with the perceptions of insects as they take shape in narratives and practices, and their roles in the manufacture and use of amulets. Then we move to a more specific analysis of the distinctive features of the various "qupirruit". PMID:20648981

  19. Freshwater biodiversity and aquatic insect diversification.

    PubMed

    Dijkstra, Klaas-Douwe B; Monaghan, Michael T; Pauls, Steffen U

    2014-01-01

    Inland waters cover less than 1% of Earth's surface but harbor more than 6% of all insect species: Nearly 100,000 species from 12 orders spend one or more life stages in freshwater. Little is known about how this remarkable diversity arose, although allopatric speciation and ecological adaptation are thought to be primary mechanisms. Freshwater habitats are highly susceptible to environmental change and exhibit marked ecological gradients. Standing waters appear to harbor more dispersive species than running waters, but there is little understanding of how this fundamental ecological difference has affected diversification. In contrast to the lack of evolutionary studies, the ecology and habitat preferences of aquatic insects have been intensively studied, in part because of their widespread use as bioindicators. The combination of phylogenetics with the extensive ecological data provides a promising avenue for future research, making aquatic insects highly suitable models for the study of ecological diversification. PMID:24160433

  20. Agricultural applications of insect ecological genomics.

    PubMed

    Poelchau, Monica F; Coates, Brad S; Childers, Christopher P; Peréz de León, Adalberto A; Evans, Jay D; Hackett, Kevin; Shoemaker, DeWayne

    2016-02-01

    Agricultural entomology is poised to benefit from the application of ecological genomics, particularly the fields of biofuels generation and pest control. Metagenomic methods can characterize microbial communities of termites, wood-boring beetles and livestock pests, and transcriptomic approaches reveal molecular bases behind wood-digesting capabilities of these insects, leading to potential mechanisms for biofuel generation. Genome sequences are being exploited to develop new pest control methods, identify candidate antigens to vaccinate livestock, and discover RNAi target sequences and potential non-target effects in other insects. Gene content analyses of pest genome sequences and their endosymbionts suggest metabolic interdependencies between organisms, exposing potential gene targets for insect control. Finally, genome-wide association studies and genotyping by high-throughput sequencing promise to improve management of pesticide resistance. PMID:27436554

  1. Damage signals in the insect immune response

    PubMed Central

    Krautz, Robert; Arefin, Badrul; Theopold, Ulrich

    2014-01-01

    Insects and mammals share an ancient innate immune system comprising both humoral and cellular responses. The insect immune system consists of the fat body, which secretes effector molecules into the hemolymph and several classes of hemocytes, which reside in the hemolymph and of protective border epithelia. Key features of wound- and immune responses are shared between insect and mammalian immune systems including the mode of activation by commonly shared microbial (non-self) patterns and the recognition of these patterns by dedicated receptors. It is unclear how metazoan parasites in insects, which lack these shared motifs, are recognized. Research in recent years has demonstrated that during entry into the insect host, many eukaryotic pathogens leave traces that alert potential hosts of the damage they have afflicted. In accordance with terminology used in the mammalian immune systems, these signals have been dubbed danger- or damage-associated signals. Damage signals are necessary byproducts generated during entering hosts either by mechanical or proteolytic damage. Here, we briefly review the current stage of knowledge on how wound closure and wound healing during mechanical damage is regulated and how damage-related signals contribute to these processes. We also discuss how sensors of proteolytic activity induce insect innate immune responses. Strikingly damage-associated signals are also released from cells that have aberrant growth, including tumor cells. These signals may induce apoptosis in the damaged cells, the recruitment of immune cells to the aberrant tissue and even activate humoral responses. Thus, this ensures the removal of aberrant cells and compensatory proliferation to replace lost tissue. Several of these pathways may have been co-opted from wound healing and developmental processes. PMID:25071815

  2. RNA interference: Applications and advances in insect toxicology and insect pest management.

    PubMed

    Kim, Young Ho; Soumaila Issa, Moustapha; Cooper, Anastasia M W; Zhu, Kun Yan

    2015-05-01

    Since its discovery, RNA interference (RNAi) has revolutionized functional genomic studies due to its sequence-specific nature of post-transcriptional gene silencing. In this paper, we provide a comprehensive review of the recent literature and summarize the current knowledge and advances in the applications of RNAi technologies in the field of insect toxicology and insect pest management. Many recent studies have focused on identification and validation of the genes encoding insecticide target proteins, such as acetylcholinesterases, ion channels, Bacillus thuringiensis receptors, and other receptors in the nervous system. RNAi technologies have also been widely applied to reveal the role of genes encoding cytochrome P450 monooxygenases, carboxylesterases, and glutathione S-transferases in insecticide detoxification and resistance. More recently, studies have focused on understanding the mechanism of insecticide-mediated up-regulation of detoxification genes in insects. As RNAi has already shown great potentials for insect pest management, many recent studies have also focused on host-induced gene silencing, in which several RNAi-based transgenic plants have been developed and tested as proof of concept for insect pest management. These studies indicate that RNAi is a valuable tool to address various fundamental questions in insect toxicology and may soon become an effective strategy for insect pest management. PMID:25987228

  3. Insect vision as model for machine vision

    NASA Astrophysics Data System (ADS)

    Osorio, D.; Sobey, Peter J.

    1992-11-01

    The neural architecture, neurophysiology and behavioral abilities of insect vision are described, and compared with that of mammals. Insects have a hardwired neural architecture of highly differentiated neurons, quite different from the cerebral cortex, yet their behavioral abilities are in important respects similar to those of mammals. These observations challenge the view that the key to the power of biological neural computation is distributed processing by a plastic, highly interconnected, network of individually undifferentiated and unreliable neurons that has been a dominant picture of biological computation since Pitts and McCulloch's seminal work in the 1940's.

  4. Remote detection of insect epidemics in conifers

    NASA Technical Reports Server (NTRS)

    Heller, R. C.

    1970-01-01

    With properly exposed color or infrared color film, discolored foliage caused by insect infestations in ponderosa pine is detectable on moderately small-scale photographs with acceptable accuracies. Black and white photographs which matched the wavebands of the ERTS multispectral scanner were combined into one additive color photo. This imagery was not as useful as photographs taken on color, color infrared, or color film with a minus blue filter. Based on the high-altitude color and color infrared photos obtained, it is concluded that only insect infestations larger than 100 meters in diameter are detectable on ERTS imagery.

  5. Two Dimensional Mechanism for Insect Hovering

    SciTech Connect

    Jane Wang, Z.

    2000-09-04

    Resolved computation of two dimensional insect hovering shows for the first time that a two dimensional hovering motion can generate enough lift to support a typical insect weight. The computation reveals a two dimensional mechanism of creating a downward dipole jet of counterrotating vortices, which are formed from leading and trailing edge vortices. The vortex dynamics further elucidates the role of the phase relation between the wing translation and rotation in lift generation and explains why the instantaneous forces can reach a periodic state after only a few strokes. The model predicts the lower limits in Reynolds number and amplitude above which the averaged forces are sufficient. (c) 2000 The American Physical Society.

  6. Selectivity of odorant receptors in insects

    PubMed Central

    Bohbot, Jonathan D.; Dickens, Joseph C.

    2012-01-01

    Insect olfactory receptors (ORs) detect chemicals, shape neuronal physiology, and regulate behavior. Although ORs have been categorized as “generalists” and “specialists” based on their ligand spectrum, both electrophysiological studies and recent pharmacological investigations show that ORs specifically recognize non-pheromonal compounds, and that our understanding of odorant-selectivity mirrors our knowledge of insect chemical ecology. As we are progressively becoming aware that ORs are activated through a variety of mechanisms, the molecular basis of odorant-selectivity and the corollary notion of broad-tuning need to be re-examined from a pharmacological and evolutionary perspective. PMID:22811659

  7. From Fossil Parasitoids to Vectors: Insects as Parasites and Hosts.

    PubMed

    Nagler, Christina; Haug, Joachim T

    2015-01-01

    Within Metazoa, it has been proposed that as many as two-thirds of all species are parasitic. This propensity towards parasitism is also reflected within insects, where several lineages independently evolved a parasitic lifestyle. Parasitic behaviour ranges from parasitic habits in the strict sense, but also includes parasitoid, phoretic or kleptoparasitic behaviour. Numerous insects are also the host for other parasitic insects or metazoans. Insects can also serve as vectors for numerous metazoan, protistan, bacterial and viral diseases. The fossil record can report this behaviour with direct (parasite associated with its host) or indirect evidence (insect with parasitic larva, isolated parasitic insect, pathological changes of host). The high abundance of parasitism in the fossil record of insects can reveal important aspects of parasitic lifestyles in various evolutionary lineages. For a comprehensive view on fossil parasitic insects, we discuss here different aspects, including phylogenetic systematics, functional morphology and a direct comparison of fossil and extant species. PMID:26597067

  8. Hormones and pheromones in regulation of insect behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Both pheromones and hormones are well recognized regulators of insect biology. However, the interactions between hormones and pheromones in coordinating insect biology are less well understood. We have studied the interactions between juvenile hormone, its precursor methyl farnesoate, and pheromon...

  9. Molecular mechanisms of phenotypic plasticity in social insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Polyphenism in insects, whereby a single genome expresses different phenotypes in response to environmental cues, is a fascinating biological phenomenon. Social insects are especially intriguing examples of phenotypic plasticity because division of labor results in the development of extreme morphol...

  10. Novel proteinase inhibitor promotes resistance to insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel Beta vulgaris serine proteinase inhibitor gene (BvSTI) and its protein are identified in response to insect feeding on B. vulgaris seedlings. BvSTI is cloned into an expression vector with constitutive promoter and transformed into Nicotiana benthamiana plants to assess BvSTI’s ability to ...

  11. Eight Ways to Catch an Insect

    ERIC Educational Resources Information Center

    Gray, Alice

    1977-01-01

    The webs of eight North American spiders are illustrated and discussed. Using these webs, the spiders are able to catch insects for their meals. Each of the webs are unique and require a different approach to the problem of food getting. (MA)

  12. Measuring Asymmetry in Insect-Plant Networks

    NASA Astrophysics Data System (ADS)

    Cruz, Cláudia P. T.; de Almeida, Adriana M.; Corso, Gilberto

    2011-03-01

    In this work we focus on interaction networks between insects and plants and in the characterization of insect plant asymmetry, an important issue in coevolution and evolutionary biology. We analyze in particular the asymmetry in the interaction matrix of animals (herbivorous insects) and plants (food resource for the insects). Instead of driving our attention to the interaction matrix itself we derive two networks associated to the bipartite network: the animal network, D1, and the plant network, D2. These networks are constructed according to the following recipe: two animal species are linked once if they interact with the same plant. In a similar way, in the plant network, two plants are linked if they interact with the same animal. To explore the asymmetry between D2 and D1 we test for a set of 23 networks from the ecologic literature networks: the difference in size, ΔL, clustering coefficient difference, ΔC, and mean connectivity difference, Δ. We used a nonparametric statistical test to check the differences in ΔL, ΔC and Δ. Our results indicate that ΔL and Δ show a significative asymmetry.

  13. Prostaglandins and their receptors in insect biology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We treat the biological significance of prostaglandins (PGs) and their known receptors in insect biology. PGs and related eicosanoids are oxygenated derivatives of arachidonic acid (AA) and two other C20 polyunsaturated fatty acids. PGs are mostly appreciated in the context of biomedicine, but a gr...

  14. Insect-Plant Relationships in Ecological Teaching.

    ERIC Educational Resources Information Center

    Fry, G. L. A.; Wratten, S. D.

    1979-01-01

    Discusses the current theories concerning the evolution of insect-plant relationships. Offers several experiments based on recent publications in this field, concerning relationships between herbivore number and plants' successional status, geographical range, geological history, and stage of growth, and also experiments on the chemical basis of…

  15. An insect pupal cell with antimicrobial properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil-dwelling insects have developed various defense mechanisms to defend against pathogen infection. The pecan weevil, Curculio caryae, spends two to three years in the soil inside an earthen cell. We hypothesized that the cell may possess antimicrobial properties. In a laboratory study, we teste...

  16. Insect Biodiversity in the Palearctic Region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect biodiversity in the Palearctic Region is described. Palearctic occupies cold, temperate, and subtropical regions of Eurasia and Africa north of the Sahara Desert together with islands of the Arctic, Atlantic and Pacific oceans. Based on currently available data, there are about 200,000 speci...

  17. Insect destroyers of Tamarisk in southeastern Kazakhstan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This monograph contains the results of research work on the insect herbivores of tamarisk in southeastern Kazakhstan, which were conducted annually for last 12 years (1994-2006), and also the information, obtained by one of the authors (Mityaev) in the mid-1950s. Studies were conducted within the f...

  18. Asymmetric radar echo patterns from insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Radar echoes from insects, birds, and bats in the atmosphere exhibit both symmetry and asymmetry in polarimetric patterns. Symmetry refers to similar magnitudes of polarimetric variables at opposite azimuths, and asymmetry relegates to differences in these magnitudes. Asymmetry can be due to diffe...

  19. Acoustic Detection of Insects in Palm Trees

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Commercial-crop and ornamental palm trees serve important functions in tropical and subtropical regions of the world, and considerable precautions are taken each year to identify and control infestations of a variety of different insect pests. Large weevils, including the red palm weevil and the co...

  20. Almond Production Manual Chapter: Insects and Mites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The navel orangeworm, Amyelois transitella (Walker), is the most important insect pest of almond in California and can cost as much as $500 dollars per acre to control when the costs of insecticides and sanitation are included. It is a native of the southwestern United States and Mexico and was firs...

  1. Magnetoreception in Eusocial Insects: An Update

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Behavioral experiments for magnetoreception in eusocial insects in the last decade are reviewed. Ants and bees use the geomagnetic field to orient and navigate in areas around their nests and in migratory paths. Bees show sensitivity to small changes in magnetic fields in conditioning experiments a...

  2. Insects: Little Things That Run the World

    ERIC Educational Resources Information Center

    Tilley, Luke

    2014-01-01

    Insects are easily the most abundant and diverse group of animals, with over 24,000 species in the UK alone. They can be found in almost every habitat on Earth and are fundamentally important to ecology, conservation, food production, animal and human health, and biodiversity. They are a prominent feature of almost every food web in the UK and…

  3. Transgenic plants protected from insect attack

    NASA Astrophysics Data System (ADS)

    Vaeck, Mark; Reynaerts, Arlette; Höfte, Herman; Jansens, Stefan; de Beuckeleer, Marc; Dean, Caroline; Zabeau, Marc; Montagu, Marc Van; Leemans, Jan

    1987-07-01

    The Gram-positive bacterium Bacillus thuringiensis produces proteins which are specifically toxic to a variety of insect species. Modified genes have been derived from bt2, a toxin gene cloned from one Bacillus strain. Transgenic tobacco plants expressing these genes synthesize insecticidal proteins which protect them from feeding damage by larvae of the tobacco hornworm.

  4. Using entomopathogenic nematodes for crop insect control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this paper is to provide an overview on using entomopathogenic nematodes for insect pest control. Entomopathogenic nematodes (genera Steinernema and Heterorhabditis), are be used as natural biopesticides. Unlike plant parasitic nematodes, which can be serious crop pests, entomopat...

  5. Mode of action of insect repellents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mode of action of DEET and other insect repellents has been a topic of interest since the discovery of DEET in the mid twentieth century. Nearly 60 years have passed since DEET applied topically to the skin was shown to be effective in preventing mosquito bites. With the discovery and characte...

  6. Insect Control (II): Hormones and Viruses

    ERIC Educational Resources Information Center

    Marx, Jean L.

    1973-01-01

    Discusses research in the use of hormones and viruses to control insect populations. Although entomologists do not think that pheromones, hormones, and viruses will completely replace more conventional chemical insecticides, they will become increasingly important and will reduce our dependence on traditional insecticides. (JR)

  7. The insect microcosm of western juniper berries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Expansion of western juniper (Juniperus occidentalis) has been a major concern of ranchers and managers working on rangelands within the geographical distribution of this tree. Establishment of new seedlings is the basis for juniper expansion. Yet, despite the fact that insects and mites associated ...

  8. Biomimetic visual detection based on insect neurobiology

    NASA Astrophysics Data System (ADS)

    O'Carroll, David C.

    2001-11-01

    With a visual system that accounts for as much as 30% of the lifted mass, flying insects such as dragonflies and hoverflies invest more in vision than any other animal. Impressive visual performance is subserved by a surprisingly simple visual system. In a typical insect eye, between 2,000 and 30,000 pixels in the image are analyzed by fewer than 200,000 neurons in underlying neural circuits. The combination of sophisticated visual processing with an approachable level of complexity has made the insect visual system a leading model for biomimetic approaches to computer vision. Much neurobiological research has focused on neural circuits used for detection of moving patterns (e.g. optical flow during flight) and moving targets (e.g. prey). Research from several labs has led to great advances in our understanding of the neural mechanisms involved, and has spawned neuromorphic hardware based on key processes identified in neurobiological experiments. Despite its attractions, the highly non-linear nature of several key stages in insect visual processing presents a challenge to understanding. I will describe examples of adaptive elements of neural circuits in the fly visual system which analyze the direction and velocity of wide-field optical flow patterns and the result of experiments that suggest that these non-linearities may contribute to robust responses to natural image motion.

  9. Insects of war, terror and torture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    From plagues to malaria transmission, insects and other arthropods have been natural or intentional health and agricultural threats to military and civilian populations throughout human history. The success or failure of military operations frequently has been determined by correctly anticipating in...

  10. Quantitative Analysis of Radar Returns from Insects

    NASA Technical Reports Server (NTRS)

    Riley, J. R.

    1979-01-01

    When a number of flying insects is low enough to permit their resolution as individual radar targets, quantitative estimates of their aerial density are developed. Accurate measurements of heading distribution using a rotating polarization radar to enhance the wingbeat frequency method of identification are presented.

  11. Hunting for insect pathogens: A genomics approach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Emerging methods within the field of genomics have increased the number of insect pathogens being discovered and characterized each year. These pathogens provide a rich resource for biological control agents, gene expression systems, and other molecular tools. Using Metagenomics, and gene expression...

  12. A Sequential Insect Dispenser for Behavioral Experiments

    ERIC Educational Resources Information Center

    Gans, Carl; Mix, Harold

    1974-01-01

    Describes the construction and operation of an automatic insect dispenser suitable for feeding small vertebrates that are being maintained for behavioral experiments. The food morsels are squirted from their chambers an an air jet, and may be directed at a particluar portion of the cage or distributed to different areas. (JR)

  13. TRANSFECTION OF INSECT CELL LINES USING POLYETHYLENIMINE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect cell lines have been widely used in recombinant baculovirus expression systems and transient gene expression studies. Critical to these applications have been the transfection of foreign DNA. This has been widely done using labor intensive and cytotoxic liposome-based transfection reagents....

  14. IRRADIATION FOR POSTHARVEST CONTROL OF QUARANTINE INSECTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest in the use of irradiation as a phytosanitary treatment for agricultural commodities is growing worldwide, particularly since international IPPC and CODEX standards now endorse and facilitate trade based on this disinfestation method. Irradiation is broadly effective against insects and mite...

  15. Insect pathogens: molecular approaches and techniques

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book serves as a primer for molecular techniques in insect pathology and is tailored for a wide scientific audience. Contributing authors are internationally recognized experts. The book comprises four sections: 1) pathogen identification and diagnostics, 2) pathogen population genetics and p...

  16. MARKING INSECTS FOR STUDYING ECOLOGY AND ETHOLOGY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Different kinds of markers can be used for studying insect ecology and behavior, and each have special strengths, weaknesses, and applications. Various kinds of markers are described, including visual tags (e.g., paint, wires, dyes, pollen, and spores), rubidium, radiotracers, rare earth elements, ...

  17. Development of Baits for Insect Control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article outlines the importance of baits. Baits are formulations that can be used to deliver a toxic chemical or a pathogen (active agent) via ingestion to an insect pest with the goal of killing it. A bait formulations consist of a bait matrix which is the carrier for an active agent. The bait...

  18. Insect Pests of Field Crops. MP-28.

    ERIC Educational Resources Information Center

    Burkhardt, Chris C.

    This document addresses the principles of field crop insect control through biological, mechanical, and chemical processes. Identification, life history, damage, pesticides, pesticide use and environmental considerations are presented for the major pests of corn, alfalfa, beans, small grains, sugar beets, and potatoes. Each section is accompanied…

  19. Insect Pests Models and Insecticide Application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the past, the dominant approach in theoretical pest management ecology has emphasized the use of simple analytical or mathematical models and the analysis of systems in equilibrium. Recent advancements in computer technology have provided the opportunity for ecological insect modelers to move aw...

  20. Plant defences against herbivore and insect attack

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plants deploy a number of defences against attack by insects and other herbivores. Direct defence is conferred by plant products and structures that deter or kill the herbivores. Chemical toxins and deterrents vary widely among plant species, and some typical toxins include alkaloids, terpenoids, st...

  1. Numerical investigation of insect wing fracture behaviour.

    PubMed

    Rajabi, H; Darvizeh, A; Shafiei, A; Taylor, D; Dirks, J-H

    2015-01-01

    The wings of insects are extremely light-weight biological composites with exceptional biomechanical properties. In the recent years, numerical simulations have become a very powerful tool to answer experimentally inaccessible questions on the biomechanics of insect flight. However, many of the presented models require a sophisticated balance of biomechanical material parameters, many of which are not yet available. In this article we show the first numerical simulations of crack propagation in insect wings. We have used a combination of the maximum-principal stress theory, the traction separation law and basic biomechanical properties of cuticle to develop simple yet accurate finite element (FE) models of locust wings. The numerical results of simulated tensile tests on wing samples are in very good qualitative, and interestingly, also in excellent quantitative agreement with previously obtained experimental data. Our study further supports the idea that the cross-veins in insect wings act as barriers against crack propagation and consequently play a dominant role in toughening the whole wing structure. The use of numerical simulations also allowed us to combine experimental data with previously inaccessible data, such as the distribution of the first principal stress through the wing membrane and the veins. A closer look at the stress-distribution within the wings might help to better understand fracture-toughening mechanisms and also to design more durable biomimetic micro-air vehicles. PMID:25468669

  2. Sustainable Biocontrol of Apple Insect Pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biocontrol of insect pests is a cornerstone to sustainable production of apples and other crops. The ecology of orchards lends itself to the application of many management options which will enhance the sustainability of biocontrol. Orchards remain in place for decades, allowing for an evolution o...

  3. Bug City: House and Backyard Insects [Videotape].

    ERIC Educational Resources Information Center

    1998

    "Bug City" is a video series created to help children learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic photography, fun…

  4. Recombinant Protein Production and Insect Cell Culture and Process

    NASA Technical Reports Server (NTRS)

    Spaulding, Glenn F. (Inventor); Goodwin, Thomas J. (Inventor); OConnor, Kim C. (Inventor); Francis, Karen M. (Inventor); Andrews, Angela D. (Inventor); Prewett, Tracey L. (Inventor)

    1997-01-01

    A process has been developed for recombinant production of selected polypeptides using transformed insect cells cultured in a horizontally rotating culture vessel modulated to create low shear conditions. A metabolically transformed insect cell line is produced using the culture procedure regardless of genetic transformation. The recombinant polypeptide can be produced by an alternative process using virtually infected or stably transformed insect cells containing a gene encoding the described polypeptide. The insect cells can also be a host for viral production.

  5. Recombinant protein production and insect cell culture and process

    NASA Technical Reports Server (NTRS)

    Spaulding, Glenn (Inventor); Prewett, Tacey (Inventor); Goodwin, Thomas (Inventor); Francis, Karen (Inventor); Andrews, Angela (Inventor); Oconnor, Kim (Inventor)

    1993-01-01

    A process has been developed for recombinant production of selected polypeptides using transformed insect cells cultured in a horizontally rotating culture vessel modulated to create low shear conditions. A metabolically transformed insect cell line is produced using the culture procedure regardless of genetic transformation. The recombinant polypeptide can be produced by an alternative process using the cultured insect cells as host for a virus encoding the described polypeptide such as baculovirus. The insect cells can also be a host for viral production.

  6. Insect overwintering in a changing climate.

    PubMed

    Bale, J S; Hayward, S A L

    2010-03-15

    Insects are highly successful animals inhabiting marine, freshwater and terrestrial habitats from the equator to the poles. As a group, insects have limited ability to regulate their body temperature and have thus required a range of strategies to support life in thermally stressful environments, including behavioural avoidance through migration and seasonal changes in cold tolerance. With respect to overwintering strategies, insects have traditionally been divided into two main groups: freeze tolerant and freeze avoiding, although this simple classification is underpinned by a complex of interacting processes, i.e. synthesis of ice nucleating agents, cryoprotectants, antifreeze proteins and changes in membrane lipid composition. Also, in temperate and colder climates, the overwintering ability of many species is closely linked to the diapause state, which often increases cold tolerance ahead of temperature-induced seasonal acclimatisation. Importantly, even though most species can invoke one or both of these responses, the majority of insects die from the effects of cold rather than freezing. Most studies on the effects of a changing climate on insects have focused on processes that occur predominantly in summer (development, reproduction) and on changes in distributions rather than winter survival per se. For species that routinely experience cold stress, a general hypothesis would be that predicted temperature increases of 1 degree C to 5 degrees C over the next 50-100 years would increase winter survival in some climatic zones. However, this is unlikely to be a universal effect. Negative impacts may occur if climate warming leads to a reduction or loss of winter snow cover in polar and sub-polar areas, resulting in exposure to more severe air temperatures, increasing frequency of freeze-thaw cycles and risks of ice encasement. Likewise, whilst the dominant diapause-inducing cue (photoperiod) will be unaffected by global climate change, higher temperatures may

  7. Similarities between decapod and insect neuropeptidomes

    PubMed Central

    2016-01-01

    Background. Neuropeptides are important regulators of physiological processes and behavior. Although they tend to be generally well conserved, recent results using trancriptome sequencing on decapod crustaceans give the impression of significant differences between species, raising the question whether such differences are real or artefacts. Methods. The BLAST+ program was used to find short reads coding neuropeptides and neurohormons in publicly available short read archives. Such reads were then used to find similar reads in the same archives, and the DNA assembly program Trinity was employed to construct contigs encoding the neuropeptide precursors as completely as possible. Results. The seven decapod species analyzed in this fashion, the crabs Eriocheir sinensis, Carcinus maenas and Scylla paramamosain, the shrimp Litopenaeus vannamei, the lobster Homarus americanus, the fresh water prawn Macrobrachium rosenbergii and the crayfish Procambarus clarkii had remarkably similar neuropeptidomes. Although some neuropeptide precursors could not be assembled, in many cases individual reads pertaining to the missing precursors show unambiguously that these neuropeptides are present in these species. In other cases, the tissues that express those neuropeptides were not used in the construction of the cDNA libraries. One novel neuropeptide was identified: elongated PDH (pigment dispersing hormone), a variation on PDH that has a two-amino-acid insertion in its core sequence. Hyrg is another peptide that is ubiquitously present in decapods and is likely a novel neuropeptide precursor. Discussion. Many insect species have lost one or more neuropeptide genes, but apart from elongated PDH and hyrg all other decapod neuropeptides are present in at least some insect species, and allatotropin is the only insect neuropeptide missing from decapods. This strong similarity between insect and decapod neuropeptidomes makes it possible to predict the receptors for decapod neuropeptides

  8. Similarities between decapod and insect neuropeptidomes.

    PubMed

    Veenstra, Jan A

    2016-01-01

    Background. Neuropeptides are important regulators of physiological processes and behavior. Although they tend to be generally well conserved, recent results using trancriptome sequencing on decapod crustaceans give the impression of significant differences between species, raising the question whether such differences are real or artefacts. Methods. The BLAST+ program was used to find short reads coding neuropeptides and neurohormons in publicly available short read archives. Such reads were then used to find similar reads in the same archives, and the DNA assembly program Trinity was employed to construct contigs encoding the neuropeptide precursors as completely as possible. Results. The seven decapod species analyzed in this fashion, the crabs Eriocheir sinensis, Carcinus maenas and Scylla paramamosain, the shrimp Litopenaeus vannamei, the lobster Homarus americanus, the fresh water prawn Macrobrachium rosenbergii and the crayfish Procambarus clarkii had remarkably similar neuropeptidomes. Although some neuropeptide precursors could not be assembled, in many cases individual reads pertaining to the missing precursors show unambiguously that these neuropeptides are present in these species. In other cases, the tissues that express those neuropeptides were not used in the construction of the cDNA libraries. One novel neuropeptide was identified: elongated PDH (pigment dispersing hormone), a variation on PDH that has a two-amino-acid insertion in its core sequence. Hyrg is another peptide that is ubiquitously present in decapods and is likely a novel neuropeptide precursor. Discussion. Many insect species have lost one or more neuropeptide genes, but apart from elongated PDH and hyrg all other decapod neuropeptides are present in at least some insect species, and allatotropin is the only insect neuropeptide missing from decapods. This strong similarity between insect and decapod neuropeptidomes makes it possible to predict the receptors for decapod neuropeptides

  9. Stored Grain Insect Area-wide Integrated Pest Management (IPM)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When wheat is mixed with wheat from other locations as it moves through the grain-marketing system, insect infestation can be spread to larger quantities of wheat, which increases the overall cost of insect pest management. In Kansas and Oklahoma, insect infestations currently are managed primarily...

  10. Automatic monitoring of insect pests in stored grain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Manual sampling of insects in stored grain is a laborious and time consuming process. Automation of grain sampling should help to increase the adoption of stored-grain integrated pest management. To make accurate insect management decisions, managers need to know both the insect species and numbers ...

  11. Expression of heat shock protein genes in insect stress responses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The heat shock proteins (HSPs) that are abundantly expressed in insects are important modulators of insect survival. Expression of HSP genes in insects is not only developmentally regulated, but also induced by various stressors in order to confer protection against such stressors. The expression o...

  12. Impact of distinct insect pollinators on gene flow

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The vast majority of fruits and vegetables, together with some hay crops (alfalfa) and some oil-producing crops (canola) are pollinated by insects. However we have little information on how insect pollinators affect the movement of genes via pollen and even less on how distinct insect pollinators ma...

  13. 46 CFR 190.20-55 - Insect screens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Insect screens. 190.20-55 Section 190.20-55 Shipping... ARRANGEMENT Accomodations for Officers, Crew, and Scientific Personnel § 190.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  14. 40 CFR 161.590 - Nontarget insect data requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Nontarget insect data requirements... § 161.590 Nontarget insect data requirements. (a) Table. Sections 161.100 through 161.102 describe how to use this table to determine the nontarget insect data requirements and the substance to be...

  15. 7 CFR 58.147 - Insect and rodent control program.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Insect and rodent control program. 58.147 Section 58... Service 1 Operations and Operating Procedures § 58.147 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control...

  16. 7 CFR 58.247 - Insect and rodent control program.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Insect and rodent control program. 58.247 Section 58... Service 1 Operations and Operating Procedures § 58.247 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control program...

  17. 7 CFR 58.247 - Insect and rodent control program.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Insect and rodent control program. 58.247 Section 58... Service 1 Operations and Operating Procedures § 58.247 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control program...

  18. 46 CFR 72.20-55 - Insect screens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 3 2013-10-01 2013-10-01 false Insect screens. 72.20-55 Section 72.20-55 Shipping COAST... Accommodations for Officers and Crew § 72.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  19. 7 CFR 58.247 - Insect and rodent control program.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Insect and rodent control program. 58.247 Section 58... Service 1 Operations and Operating Procedures § 58.247 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control program...

  20. 40 CFR 161.590 - Nontarget insect data requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Nontarget insect data requirements... § 161.590 Nontarget insect data requirements. (a) Table. Sections 161.100 through 161.102 describe how to use this table to determine the nontarget insect data requirements and the substance to be...

  1. 46 CFR 190.20-55 - Insect screens.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Insect screens. 190.20-55 Section 190.20-55 Shipping... ARRANGEMENT Accomodations for Officers, Crew, and Scientific Personnel § 190.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  2. 25 CFR 163.31 - Insect and disease control.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Insect and disease control. 163.31 Section 163.31 Indians... Management and Operations § 163.31 Insect and disease control. (a) The Secretary is authorized to protect and preserve Indian forest land from disease or insects (Sept. 20, 1922, Ch. 349, 42 Stat. 857). The...

  3. 46 CFR 190.20-55 - Insect screens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Insect screens. 190.20-55 Section 190.20-55 Shipping... ARRANGEMENT Accomodations for Officers, Crew, and Scientific Personnel § 190.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  4. 20 CFR 654.415 - Insect and rodent control.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Insect and rodent control. 654.415 Section 654.415 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR SPECIAL... Insect and rodent control. Housing and facilities shall be free of insects, rodents, and other vermin....

  5. 20 CFR 654.415 - Insect and rodent control.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 3 2014-04-01 2014-04-01 false Insect and rodent control. 654.415 Section 654.415 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR SPECIAL... Insect and rodent control. Housing and facilities shall be free of insects, rodents, and other vermin....

  6. 7 CFR 58.247 - Insect and rodent control program.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Insect and rodent control program. 58.247 Section 58... Service 1 Operations and Operating Procedures § 58.247 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control program...

  7. 25 CFR 163.31 - Insect and disease control.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Insect and disease control. 163.31 Section 163.31 Indians... Management and Operations § 163.31 Insect and disease control. (a) The Secretary is authorized to protect and preserve Indian forest land from disease or insects (Sept. 20, 1922, Ch. 349, 42 Stat. 857). The...

  8. 46 CFR 72.20-55 - Insect screens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Insect screens. 72.20-55 Section 72.20-55 Shipping COAST... Accommodations for Officers and Crew § 72.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  9. 46 CFR 72.20-55 - Insect screens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 3 2014-10-01 2014-10-01 false Insect screens. 72.20-55 Section 72.20-55 Shipping COAST... Accommodations for Officers and Crew § 72.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  10. 20 CFR 654.415 - Insect and rodent control.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 3 2013-04-01 2013-04-01 false Insect and rodent control. 654.415 Section 654.415 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR SPECIAL... Insect and rodent control. Housing and facilities shall be free of insects, rodents, and other vermin....

  11. 46 CFR 92.20-55 - Insect screens.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Insect screens. 92.20-55 Section 92.20-55 Shipping COAST... ARRANGEMENT Accommodations for Officers and Crew § 92.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  12. 46 CFR 92.20-55 - Insect screens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Insect screens. 92.20-55 Section 92.20-55 Shipping COAST... ARRANGEMENT Accommodations for Officers and Crew § 92.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  13. 46 CFR 92.20-55 - Insect screens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Insect screens. 92.20-55 Section 92.20-55 Shipping COAST... ARRANGEMENT Accommodations for Officers and Crew § 92.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  14. 46 CFR 92.20-55 - Insect screens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Insect screens. 92.20-55 Section 92.20-55 Shipping COAST... ARRANGEMENT Accommodations for Officers and Crew § 92.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  15. 20 CFR 654.415 - Insect and rodent control.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Insect and rodent control. 654.415 Section 654.415 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR SPECIAL... Insect and rodent control. Housing and facilities shall be free of insects, rodents, and other vermin....

  16. 46 CFR 190.20-55 - Insect screens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Insect screens. 190.20-55 Section 190.20-55 Shipping... ARRANGEMENT Accomodations for Officers, Crew, and Scientific Personnel § 190.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  17. 40 CFR 161.590 - Nontarget insect data requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Nontarget insect data requirements... § 161.590 Nontarget insect data requirements. (a) Table. Sections 161.100 through 161.102 describe how to use this table to determine the nontarget insect data requirements and the substance to be...

  18. 25 CFR 163.31 - Insect and disease control.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Insect and disease control. 163.31 Section 163.31 Indians... Management and Operations § 163.31 Insect and disease control. (a) The Secretary is authorized to protect and preserve Indian forest land from disease or insects (Sept. 20, 1922, Ch. 349, 42 Stat. 857). The...

  19. 20 CFR 654.415 - Insect and rodent control.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 3 2012-04-01 2012-04-01 false Insect and rodent control. 654.415 Section 654.415 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR SPECIAL... Insect and rodent control. Housing and facilities shall be free of insects, rodents, and other vermin....

  20. 40 CFR 161.590 - Nontarget insect data requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Nontarget insect data requirements... § 161.590 Nontarget insect data requirements. (a) Table. Sections 161.100 through 161.102 describe how to use this table to determine the nontarget insect data requirements and the substance to be...

  1. 46 CFR 190.20-55 - Insect screens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Insect screens. 190.20-55 Section 190.20-55 Shipping... ARRANGEMENT Accomodations for Officers, Crew, and Scientific Personnel § 190.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  2. 25 CFR 163.31 - Insect and disease control.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Insect and disease control. 163.31 Section 163.31 Indians... Management and Operations § 163.31 Insect and disease control. (a) The Secretary is authorized to protect and preserve Indian forest land from disease or insects (Sept. 20, 1922, Ch. 349, 42 Stat. 857). The...

  3. 46 CFR 92.20-55 - Insect screens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Insect screens. 92.20-55 Section 92.20-55 Shipping COAST... ARRANGEMENT Accommodations for Officers and Crew § 92.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  4. 7 CFR 58.147 - Insect and rodent control program.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Insect and rodent control program. 58.147 Section 58... Service 1 Operations and Operating Procedures § 58.147 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control...

  5. 7 CFR 58.147 - Insect and rodent control program.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Insect and rodent control program. 58.147 Section 58... Service 1 Operations and Operating Procedures § 58.147 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control...

  6. 7 CFR 58.247 - Insect and rodent control program.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Insect and rodent control program. 58.247 Section 58... Service 1 Operations and Operating Procedures § 58.247 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control program...

  7. 7 CFR 58.147 - Insect and rodent control program.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Insect and rodent control program. 58.147 Section 58... Service 1 Operations and Operating Procedures § 58.147 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control...

  8. 7 CFR 58.147 - Insect and rodent control program.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Insect and rodent control program. 58.147 Section 58... Service 1 Operations and Operating Procedures § 58.147 Insect and rodent control program. In addition to... made responsible for the performance of a regularly scheduled insect and rodent control...

  9. 46 CFR 72.20-55 - Insect screens.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Insect screens. 72.20-55 Section 72.20-55 Shipping COAST... Accommodations for Officers and Crew § 72.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  10. 46 CFR 72.20-55 - Insect screens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 3 2011-10-01 2011-10-01 false Insect screens. 72.20-55 Section 72.20-55 Shipping COAST... Accommodations for Officers and Crew § 72.20-55 Insect screens. Provisions must be made to protect the crew quarters against the admission of insects....

  11. 25 CFR 163.31 - Insect and disease control.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Insect and disease control. 163.31 Section 163.31 Indians... Management and Operations § 163.31 Insect and disease control. (a) The Secretary is authorized to protect and preserve Indian forest land from disease or insects (Sept. 20, 1922, Ch. 349, 42 Stat. 857). The...

  12. Coconut leaf bioactivity toward generalist maize insect pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tropical plants are often more resistant to insects than temperate plants due to evolution of robust defenses to cope with a more constant insect threat. Coconut (Cocos nucifera L.) has very few chewing leaf feeding insect pests and was tested against two omnivorous leaf feeding caterpillar species,...

  13. Grain sorghum hybrid resistance to insect and bird damage - 2015

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A total of 26 grain sorghum hybrids (24 commercial grain sorghum hybrids and a pair of sugarcane aphid resistant and susceptible controls) were evaluated for resistance to insect and bird damage in Tifton, Georgia. A total of 10 insect pests were observed. The insect pests in order of importance are...

  14. Bridging conventional and molecular genetics of sorghum insect resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sustainable production of sorghum, Sorghum bicolor (L.) Moench, depends on effective control of insect pests as they continue to compete with humans for the sorghum crop. Insect pests are major constraint in sorghum production, and nearly 150 insect species are serious pests of this crop worldwide,...

  15. Job Grading Standard for Insects Production Worker WG-5031.

    ERIC Educational Resources Information Center

    Civil Service Commission, Washington, DC. Bureau of Policies and Standards.

    The standard is for grading nonsupervisory jobs involved in reproducing, collecting, and caring for insect collections. The work requires practical knowledge of the characteristics of insects and their needs, and skill in observing and handling them. The levels of insects production worker WG-3, WG-4, and WG-5 are differentiated by describing the…

  16. Exploring the Insect World, An Outdoor Teaching Technique.

    ERIC Educational Resources Information Center

    Rillo, Thomas J.

    Information about the insect world and its advantages for the elementary classroom teacher is given in this paper, along with activities which can teach students about insects. The insect world tends to be noticed by the average person only when the small creatures become pests or inhabit man's abode. However, young students have a sharp sense of…

  17. Metabolomics reveals insect metabolic responses associated with fungal infection.

    PubMed

    Xu, Yong-Jiang; Luo, Feifei; Gao, Qiang; Shang, Yanfang; Wang, Chengshu

    2015-06-01

    The interactions between insects and pathogenic fungi are complex. We employed metabolomic techniques to profile insect metabolic dynamics upon infection by the pathogenic fungus Beauveria bassiana. Silkworm larvae were infected with fungal spores and microscopic observations demonstrated that the exhaustion of insect hemocytes was coupled with fungal propagation in the insect body cavity. Metabolomic analyses revealed that fungal infection could significantly alter insect energy and nutrient metabolisms as well as the immune defense responses, including the upregulation of carbohydrates, amino acids, fatty acids, and lipids, but the downregulation of eicosanoids and amines. The insect antifeedant effect of the fungal infection was evident with the reduced level of maclurin (a component of mulberry leaves) in infected insects but elevated accumulations in control insects. Insecticidal and cytotoxic mycotoxins like oosporein and beauveriolides were also detected in insects at the later stages of infection. Taken together, the metabolomics data suggest that insect immune responses are energy-cost reactions and the strategies of nutrient deprivation, inhibition of host immune responses, and toxin production would be jointly employed by the fungus to kill insects. The data obtained in this study will facilitate future functional studies of genes and pathways associated with insect-fungus interactions. PMID:25895944

  18. Grain sorghum hybrid resistance to insect and bird damage-2014

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty seven grain sorghum hybrids were evaluated for resistance to insect and bird damage in 2014 in Tifton, and a total of 10 insect pests were observed. While sorghum midge and bird damage was relatively low, sorghum webworm and aphid damage was high. Those insects in order of importance are: sug...

  19. Converting insect colony waste into a potting susbstrate.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rearing insect generates both a solid and semisolid waste that is generally discarded in landfills. A study was initiated to determine if the semi-solid insect colony waste product and vermiculite used in insect rearing could be combined and used as a growth substrate for plants. The semi-solid larv...

  20. Insect-attracting and antimicrobial properties of antifreeze for monitoring insect pests and natural enemies in stored corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect infestations in stored grain cause extensive damage worldwide. Storage insect pests including the Indianmeal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), Sitophilus spp. (Coleoptera: Curculionidae) and their natural enemies [e.g., Cephalonomia tarsalis (Ashmead) (Hymenopter...

  1. Selectable markers with potential activity against insects, plus other insect-oriented strategies for mycotoxin reduction in Midwest corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reduction of insect damage has the potential to greatly reduce the levels of mycotoxins in corn, as studies with Bt corn have shown. However, the large number of insect species involved necessitates the development of comprehensive insect control to most effectively utilize this strategy. One stra...

  2. External Insect Morphology: A Negative Factor in Attitudes toward Insects and Likelihood of Incorporation in Future Science Education Settings

    ERIC Educational Resources Information Center

    Wagler, Ron; Wagler, Amy

    2012-01-01

    This study investigated if the external morphology of an insect had a negative effect on United States (US) preservice elementary teacher's attitudes toward insects and beliefs concerning the likelihood of incorporating insects into future science education settings. 270 US kindergarten through sixth grade preservice elementary teachers…

  3. Flight investigation of insect contamination and its alleviation

    NASA Technical Reports Server (NTRS)

    Peterson, J. B., Jr.; Fisher, D. F.

    1978-01-01

    An investigation of leading edge contamination by insects was conducted with a JetStar airplane instrumented to detect transition on the outboard leading edge flap and equipped with a system to spray the leading edge in flight. The results of airline type flights with the JetStar indicated that insects can contaminate the leading edge during takeoff and climbout. The results also showed that the insects collected on the leading edges at 180 knots did not erode at cruise conditions for a laminar flow control airplane and caused premature transition of the laminar boundary layer. None of the superslick and hydrophobic surfaces tested showed any significant advantages in alleviating the insect contamination problem. While there may be other solutions to the insect contamination problem, the results of these tests with a spray system showed that a continouous water spray while encountering the insects is effective in preventing insect contamination of the leading edges.

  4. Emerging strategies for RNA interference (RNAi) applications in insects

    PubMed Central

    Nandety, Raja Sekhar; Kuo, Yen-Wen; Nouri, Shahideh; Falk, Bryce W

    2015-01-01

    RNA interference (RNAi) in insects is a gene regulatory process that also plays a vital role in the maintenance and in the regulation of host defenses against invading viruses. Small RNAs determine the specificity of the RNAi through precise recognition of their targets. These small RNAs in insects comprise small interfering RNAs (siRNAs), micro RNAs (miRNAs) and Piwi interacting RNAs (piRNAs) of various lengths. In this review, we have explored different forms of the RNAi inducers that are presently in use, and their applications for an effective and efficient fundamental and practical RNAi research with insects. Further, we reviewed trends in next generation sequencing (NGS) technologies and their importance for insect RNAi, including the identification of novel insect targets as well as insect viruses. Here we also describe a rapidly emerging trend of using plant viruses to deliver the RNAi inducer molecules into insects for an efficient RNAi response. PMID:25424593

  5. Velocity correlations in laboratory insect swarms

    NASA Astrophysics Data System (ADS)

    Ni, R.; Ouellette, N. T.

    2015-12-01

    In contrast to animal groups such as bird flocks or migratory herds that display net, directed motion, insect swarms do not possess global order. Without such order, it is difficult to define and characterize the transition to collective behavior in swarms; nevertheless, visual observation of swarms strongly suggests that swarming insects do behave collectively. It has recently been suggested that correlation rather than order is the hallmark of emergent collective behavior. Here, we report measurements of spatial velocity correlation functions in laboratory mating swarms of the non-biting midge Chironomus riparius. Although we find some correlation at short distances, our swarms are in general only weakly correlated, in contrast to what has been observed in field studies. Our results hint at the potentially important role of environmental conditions on collective behavior, and suggest that general indicators of the collective nature of swarming are still needed.

  6. Insects and Spiders: Infestations and Bites

    PubMed Central

    Turgeon, E.W.T.

    1987-01-01

    Despite successful eradication techniques and specific effective therapies, insect bites and infestations remain a source of great human misery. The current scabies pandemic shows no signs of abating. Bed bugs, which through the ages have been second only to the malarial mosquito as an insect vector of fatal infection, have now been implicated in the transmission of Hepatitis B and possibly African acquired immune deficiency syndrome (AIDS). The incidence of head- and pubic lice is on the rise, the latter paralleling, and often co-existing with, other sexually transmitted diseases. Black widow spiders are native to many populous areas in southern Canada, and the brown recluse spider's range now encompasses Canada, thanks to moving vans and central heating. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:21263961

  7. Comparative magnetic measurements on social insects

    NASA Astrophysics Data System (ADS)

    Ferreira, Jandira; Cernicchiaro, Geraldo; Winklhofer, Michael; Dutra, Humberto; de Oliveira, Paulo S.; S. Esquivel, Darci M.; Wajnberg, Eliane

    2005-03-01

    Biogenic magnetite has been detected in several species of social insects and may well form the basis of a magnetic sensory system in these animals, although other physiological functions are possible, too. We report here on hysteresis measurements on honeybees ( Apis mellifera) and the termite Neocapritermes opacus. The ratio of saturation remanence to saturation magnetization, Jrs/ Js, was determined as 0.11 (0.15) in bees (termite), the coercive force Hc as 90 (50 Oe). The magnetic remanence is generally low (of the order of 10 -6 emu per individual). The values obtained are similar to the ones reported previously on a migratory ant species, which suggests that biomineralization of magnetic material in social insects may underlie a generic process.

  8. Managing social insects of urban importance.

    PubMed

    Rust, Michael K; Su, Nan-Yao

    2012-01-01

    Social insects have a tremendous economic and social impact on urban communities. The rapid urbanization of the world has dramatically increased the incidence of urban pests. Human commerce has resulted in the spread of urban invasive species worldwide such that various species are now common to many major urban centers. We aim to highlight those social behaviors that can be exploited to control these pests with the minimal use of pesticides. Their cryptic behavior often prohibits the direct treatment of colonies. However, foraging and recruitment are essential aspects of their social behavior and expose workers to traps, baits, and pesticide applications. The advent of new chemistries has revolutionized the pest management strategies used to control them. In recent years, there has been an increased environmental awareness, especially in the urban community. Advances in molecular and microbial agents promise additional tools in developing integrated pest management programs against social insects. PMID:21942844

  9. Vision and visual navigation in nocturnal insects.

    PubMed

    Warrant, Eric; Dacke, Marie

    2011-01-01

    With their highly sensitive visual systems, nocturnal insects have evolved a remarkable capacity to discriminate colors, orient themselves using faint celestial cues, fly unimpeded through a complicated habitat, and navigate to and from a nest using learned visual landmarks. Even though the compound eyes of nocturnal insects are significantly more sensitive to light than those of their closely related diurnal relatives, their photoreceptors absorb photons at very low rates in dim light, even during demanding nocturnal visual tasks. To explain this apparent paradox, it is hypothesized that the necessary bridge between retinal signaling and visual behavior is a neural strategy of spatial and temporal summation at a higher level in the visual system. Exactly where in the visual system this summation takes place, and the nature of the neural circuitry that is involved, is currently unknown but provides a promising avenue for future research. PMID:20822443

  10. Studying insect motion with piezoelectric sensors

    NASA Astrophysics Data System (ADS)

    Mika, Bartosz; Lee, Hyungoo; González, Jorge M.; Vinson, S. Bradleigh; Liang, Hong

    2007-04-01

    Piezoelectric materials have been widely used in applications such as transducers, acoustic components, as well as motion, pressure and airborne sensors. Because of the material's biocompatibility and flexibility, we have been able to apply small piezoelectric sensors, made of PVDF, to cockroaches. We built a laboratory test system to study the piezoelectric properties of a bending sensor. The tested motion was compared with that of the sensor attached to a cockroach. Surface characterization and finite element analysis revealed the effects of microstructure on piezoelectric response. The sensor attachment enables us to monitor the insects' locomotion and study their behaviors. The applications of engineering materials to insects opens the door to innovating approaches to integrating biological, mechanical and electrical systems.

  11. Remote Radio Control of Insect Flight

    PubMed Central

    Sato, Hirotaka; Berry, Christopher W.; Peeri, Yoav; Baghoomian, Emen; Casey, Brendan E.; Lavella, Gabriel; VandenBrooks, John M.; Harrison, Jon F.; Maharbiz, Michel M.

    2009-01-01

    We demonstrated the remote control of insects in free flight via an implantable radio-equipped miniature neural stimulating system. The pronotum mounted system consisted of neural stimulators, muscular stimulators, a radio transceiver-equipped microcontroller and a microbattery. Flight initiation, cessation and elevation control were accomplished through neural stimulus of the brain which elicited, suppressed or modulated wing oscillation. Turns were triggered through the direct muscular stimulus of either of the basalar muscles. We characterized the response times, success rates, and free-flight trajectories elicited by our neural control systems in remotely controlled beetles. We believe this type of technology will open the door to in-flight perturbation and recording of insect flight responses. PMID:20161808

  12. Mechanisms of tracheal filling in insects.

    PubMed

    Förster, Thomas D; Woods, H Arthur

    2013-02-01

    Insects exchange respiratory gases primarily using tracheal systems that are filled with gas. However, in different developmental and environmental circumstances, liquid can occupy the tracheal system, which can significantly impair its respiratory function. Insects therefore use a suite of mechanisms for tracheal filling, which is the process of replacing tracheal liquids with gas. We review these mechanisms for liquid removal and gas filling. By integrating recent molecular work with older physiological literature, we show that liquid removal likely involves active ion transport in the whole tracheal system. Gas filling reveals fascinating interactions between geometry, surface chemistry of the tracheal walls, the tracheal liquid, and dissolved gases. The temporal proximity to moulting allows for potentially complex interdependencies between gas filling, moult-associated hormone signaling, and cuticle sclerotization. We propose a mechanistic model for tracheal filling. However, because the composition of the liquid is unknown, it remains hypothetical. PMID:22616845

  13. Potent limonoid insect antifeedant from Melia azedarach.

    PubMed

    Carpinella, Cecilia; Ferrayoli, Carlos; Valladares, Graciela; Defago, Maria; Palacios, Sara

    2002-08-01

    Systematic fractionation of a fruit extract from Argentine Melia azedarach L., which was monitored by an insect antifeedant bioassay, led to the isolation of meliartenin, a limonoid antifeedant, which existed as a mixture of two interchangeable isomers. At 4 microg/cm2 and 1 microg/cm2, the isomeric mixture was as active as azadirachtin in strongly inhibiting the larval feeding of Epilachna paenulata Germ. (Coleoptera: Coccinellidae) and the polyphagous pest, Spodoptera eridania (Lepidoptera: Noctuidae), respectively. PMID:12353636

  14. Cultivating Insect Cells To Produce Recombinant Proteins

    NASA Technical Reports Server (NTRS)

    Spaulding, Glenn; Goodwin, Thomas; Prewett, Tacey; Andrews, Angela; Francis, Karen; O'Connor, Kim

    1996-01-01

    Method of producing recombinant proteins involves growth of insect cells in nutrient solution in cylindrical bioreactor rotating about cylindrical axis, oriented horizontally and infecting cells with viruses into which genes of selected type cloned. Genes in question those encoding production of desired proteins. Horizontal rotating bioreactor preferred for use in method, denoted by acronym "HARV", described in "High-Aspect-Ratio Rotating Cell-Culture Vessel" (MSC-21662).

  15. Dynamic flight stability of hovering insects

    NASA Astrophysics Data System (ADS)

    Sun, Mao; Wang, Jikang; Xiong, Yan

    2007-06-01

    The equations of motion of an insect with flapping wings are derived and then simplified to that of a flying body using the “rigid body” assumption. On the basis of the simplified equations of motion, the longitudinal dynamic flight stability of four insects (hoverfly, cranefly, dronefly and hawkmoth) in hovering flight is studied (the mass of the insects ranging from 11 to 1,648 mg and wingbeat frequency from 26 to 157 Hz). The method of computational fluid dynamics is used to compute the aerodynamic derivatives and the techniques of eigenvalue and eigenvector analysis are used to solve the equations of motion. The validity of the “rigid body” assumption is tested and how differences in size and wing kinematics influence the applicability of the “rigid body” assumption is investigated. The primary findings are: (1) For insects considered in the present study and those with relatively high wingbeat frequency (hoverfly, drone fly and bumblebee), the “rigid body” assumption is reasonable, and for those with relatively low wingbeat frequency (cranefly and howkmoth), the applicability of the “rigid body” assumption is questionable. (2) The same three natural modes of motion as those reported recently for a bumblebee are identified, i.e., one unstable oscillatory mode, one stable fast subsidence mode and one stable slow subsidence mode. (3) Approximate analytical expressions of the eigenvalues, which give physical insight into the genesis of the natural modes of motion, are derived. The expressions identify the speed derivative M u (pitching moment produced by unit horizontal speed) as the primary source of the unstable oscillatory mode and the stable fast subsidence mode and Z w (vertical force produced by unit vertical speed) as the primary source of the stable slow subsidence mode.

  16. The visual system of male scale insects

    NASA Astrophysics Data System (ADS)

    Buschbeck, Elke K.; Hauser, Martin

    2009-03-01

    Animal eyes generally fall into two categories: (1) their photoreceptive array is convex, as is typical for camera eyes, including the human eye, or (2) their photoreceptive array is concave, as is typical for the compound eye of insects. There are a few rare examples of the latter eye type having secondarily evolved into the former one. When viewed in a phylogenetic framework, the head morphology of a variety of male scale insects suggests that this group could be one such example. In the Margarodidae (Hemiptera, Coccoidea), males have been described as having compound eyes, while males of some more derived groups only have two single-chamber eyes on each side of the head. Those eyes are situated in the place occupied by the compound eye of other insects. Since male scale insects tend to be rare, little is known about how their visual systems are organized, and what anatomical traits are associated with this evolutionary transition. In adult male Margarodidae, one single-chamber eye (stemmateran ocellus) is present in addition to a compound eye-like region. Our histological investigation reveals that the stemmateran ocellus has an extended retina which is formed by concrete clusters of receptor cells that connect to its own first-order neuropil. In addition, we find that the ommatidia of the compound eyes also share several anatomical characteristics with simple camera eyes. These include shallow units with extended retinas, each of which is connected by its own small nerve to the lamina. These anatomical changes suggest that the margarodid compound eye represents a transitional form to the giant unicornal eyes that have been described in more derived species.

  17. Oxygen Reperfusion Damage in an Insect

    PubMed Central

    Lighton, John R. B.; Schilman, Pablo E.

    2007-01-01

    The deleterious effects of anoxia followed by reperfusion with oxygen in higher animals including mammals are well known. A convenient and genetically well characterized small-animal model that exhibits reproducible, quantifiable oxygen reperfusion damage is currently lacking. Here we describe the dynamics of whole-organism metabolic recovery from anoxia in an insect, Drosophila melanogaster, and report that damage caused by oxygen reperfusion can be quantified in a novel but straightforward way. We monitored CO2 emission (an index of mitochondrial activity) and water vapor output (an index of neuromuscular control of the spiracles, which are valves between the outside air and the insect's tracheal system) during entry into, and recovery from, rapid-onset anoxia exposure with durations ranging from 7.5 to 120 minutes. Anoxia caused a brief peak of CO2 output followed by knock-out. Mitochondrial respiration ceased and the spiracle constrictor muscles relaxed, but then re-contracted, presumably powered by anaerobic processes. Reperfusion to sustained normoxia caused a bimodal re-activation of mitochondrial respiration, and in the case of the spiracle constrictor muscles, slow inactivation followed by re-activation. After long anoxia durations, both the bimodality of mitochondrial reactivation and the recovery of spiracular control were impaired. Repeated reperfusion followed by episodes of anoxia depressed mitochondrial respiratory flux rates and damaged the integrity of the spiracular control system in a dose-dependent fashion. This is the first time that physiological evidence of oxygen reperfusion damage has been described in an insect or any invertebrate. We suggest that some of the traditional approaches of insect respiratory biology, such as quantifying respiratory water loss, may facilitate using D. melanogaster as a convenient, well-characterized experimental model for studying the underlying biology and mechanisms of ischemia and reperfusion damage and its

  18. The ubiquity and ancestry of insect doublesex

    PubMed Central

    Price, Dana C.; Egizi, Andrea; Fonseca, Dina M.

    2015-01-01

    The doublesex (dsx) gene functions as a molecular switch at the base of the insect sex determination cascade, and triggers male or female somatic sexual differentiation in Drosophila. Having been reported from only seven current insect orders, the exact phylogenetic distribution of dsx within the largest Arthropod sub-phylum, the Hexapoda, is unknown. To understand the evolution of this integral gene relative to other arthropods, we tested for the presence of dsx within public EST and genome sequencing projects representative of all 32 hexapod orders. We find the dsx gene to be ubiquitous, with putative orthologs recovered from 30 orders. Additionally, we recovered both alternatively spliced and putative paralogous dsx transcripts from several orders of hexapods, including basal lineages, indicating the likely presence of these characteristics in the hexapod common ancestor. Of note, other arthropods such as chelicerates and crustaceans express two dsx genes, both of which are shown to lack alternative splicing. Furthermore, we discovered a large degree of length heterogeneity in the common region of dsx coding sequences within and among orders, possibly resulting from lineage-specific selective pressures inherent to each taxon. Our work serves as a valuable resource for understanding the evolution of sex determination in insects. PMID:26278009

  19. Regulating the contraction of insect flight muscle.

    PubMed

    Bullard, Belinda; Pastore, Annalisa

    2011-12-01

    The rapid movement of the wings in small insects is powered by the indirect flight muscles. These muscles are capable of contracting at up to 1,000 Hz because they are activated mechanically by stretching. The mechanism is so efficient that it is also used in larger insects like the waterbug, Lethocerus. The oscillatory activity of the muscles occurs a low concentration of Ca(2+), which stays constant as the muscles contract and relax. Activation by stretch requires particular isoforms of tropomyosin and the troponin complex on the thin filament. We compare the tropomyosin and troponin of Lethocerus and Drosophila with that of vertebrates. The characteristics of the flight muscle regulatory proteins suggest ways in which stretch-activation works. There is evidence for bridges between troponin on thin filaments and myosin crossbridges on the thick filaments. Recent X-ray fibre diffraction results suggest that a pull on the bridges activates the thin filament by shifting tropomyosin from a blocking position on actin. The troponin bridges are likely to contain extended sequences of tropomyosin or troponin I (TnI). Flight muscle has two isoforms of TnC with different Ca(2+)-binding properties: F1 TnC is needed for stretch-activation and F2 TnC for isometric contractions. In this review, we describe the structural changes in both isoforms on binding Ca(2+) and TnI, and discuss how the steric model of muscle regulation can apply to insect flight muscle. PMID:22105701

  20. Insect repellents: historical perspectives and new developments.

    PubMed

    Katz, Tracy M; Miller, Jason H; Hebert, Adelaide A

    2008-05-01

    Arthropod bites remain a major cause of patient morbidity. These bites can cause local or systemic effects that may be infectious or inflammatory in nature. Arthropods, notably insects and arachnids, are vectors of potentially serious ailments including malaria, West Nile virus, dengue, and Lyme disease. Measures to curtail the impact of insect bites are important in the worldwide public health effort to safely protect patients and prevent the spread of disease. The history of insect repellent (IR) lends insight into some of the current scientific strategies behind newer products. Active ingredients of currently available IRs include N,N-diethyl-3-methylbenzamide (DEET), botanicals, citronella, and, the newest agent, picaridin. Currently, the Environmental Protection Agency's registered IR ingredients approved for application to the skin include DEET, picaridin, MGK-326, MGK-264, IR3535, oil of citronella, and oil of lemon eucalyptus. DEET has reigned as the most efficacious and broadly used IR for the last 6 decades, with a strong safety record and excellent protection against ticks, mosquitoes, and other arthropods. Newer agents, like picaridin and natural products such as oil of lemon eucalyptus are becoming increasingly popular because of their low toxicity, comparable efficacy, and customer approval. Various characteristics and individual product advantages may lead physicians to recommend one agent over another. PMID:18272250