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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Studies on the perception of quinones by the American cockroach, Periplaneta americana

Rozental, Jack Morry, January 1975 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1975. / Vita. Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
2

The Effects of Food Quality on the Life History Tactics of the American Cockroach, Periplaneta americana / Effects of Food Quality on the American Cockroach

Kajiura, Lovaye 08 1900 (has links)
The American cockroach, Periplaneta americana, is an abundant and globally distributed species. Much of its success is attributed to its remarkable ability to alter rates and utilization efficiencies of behavioural and physiological processes so as to maintain growth and reproduction within nutritionally variable environments. This study utilized artificial diets diluted with cellulose to investigate the impact of food quality on the life history tactics of this species and the compensatory mechanisms involved in offsetting these impacts. To investigate the impact of diet quality on the life history tactics of the American cockroach, seven dietary regimes were implemented. The control condition consisted of an unaltered 100% quality diet. The remaining six treatments were diluted with cellulose resulting in diet qualities of 50%, 25%, 10%, 5%, 2.5%, and 0%. The parameters examined included mortality, longevity, instar number, instar durations, growth, maturation dates, maturation sizes, dry mass budgets, and reproduction. The dry mass budgets involved observations of growth rate, feeding rate, assimilation rate, respiration rate, assimilation efficiency, efficiency of conversion of ingested food into biomass, and efficiency of conversion of digested food into biomass. Reproductive studies entailed observations of oothecal production, oviposition intervals, inter-oviposition intervals, mass of oothecae, oothecal dimensions, egg number, oothecal cannibalism, and hatching dates. Strongly canalized development was achieved by resilient compensatory responses indicative of altered physiological and behavioural features. Cockroaches developed and reproduced adequately even when nutrient concentration was reduced to 25% of the controls. The declines in various key parameters were considerably less than expected from the degree of dietary dilution. In addition, elevated consumption and enhanced conversion efficiencies strongly suggest that cockroaches normally function at submaximal levels. The applied relevance of this research entails possible ramifications into the regulation and control of cockroaches. Furthermore, such knowledge enhances our understanding of not only diverse lifestyles but also the degree of variability to which insects may modify life history features in response to resource supply. / Thesis / Master of Science (MS)
3

Biogene Aminrezeptoren der Schabe Periplaneta americana : Identifizierung, Charakterisierung und Lokalisierung von PeaTYR1 und PeaDOP2 / Biogenic amine receptors of Periplaneta americana : identification, characterization and localization of PeaTYR1 and PeaDOP2

Krach, Christian January 2007 (has links)
Biogene Amine sind eine Substanzklasse, die bei Vertebraten und Invertebraten eine wichtige Komponente des endokrinen Systems darstellen. Sie binden an spezifische Rezeptoren der Gruppe der G-Protein gekoppelten Rezeptoren. In dieser Arbeit wurden zwei neue Rezeptoren aus der Schabe Periplaneta americana kloniert. Durch verschiedene Ansätze konnten zwei vollständige cDNA-Sequenzen isoliert werden. Die Aminosäuresequenzen weisen die größte Ähnlichkeit zu bereits bekannten Tyraminrezeptoren aus Locusta/Bombyx bzw. zu Dopaminrezeptoren aus Apis/Drosophila auf. Entsprechend wurden diese Rezeptoren Pea (P. americana) TYR1 und PeaDOP2 genannt. Deutliche Hinweise auf ihre Funktion lassen sich an den abgeleiteten Aminosäuresequenzen ablesen. Aminosäuren, die wichtig bei der Bildung der Bindungstasche, der Rezeptoraktivierung und der Kopplung eines G-Proteins sind, treten bei beiden Rezeptoren auf. Sequenzalignments stellen die Rezeptoren in die Gruppe anderer Tyraminrezeptoren bzw. der Invertebraten-Typ Dopaminrezeptoren. Das Transkript der beiden Rezeptoren konnte durch RT-PCR in verschiedenen Geweben nachgewiesen werden. Ein Ziel der Arbeit war die Gewinnung eines polyklonalen Antiserums gegen PeaTYR1. Dieses Serum detektiert im Homogenat von Gehirnen mehrere Banden, darunter auch eine mit der kalkulierten Masse von PeaTYR1. Präabsorption des Serums mit dem Peptid, welches zur Reinigung verwendet wurde, zeigt dessen Spezifität. An Gehirnschnitten markiert das Serum große Teile des Protocerebrums aber auch feinere Strukturen der Antennalloben, der optischen Loben und des Zentralkomplexes. Ein weiteres Serum gegen Tyramin führte zu einer Markierung von mehreren Neuronengruppen, welche sich in die optischen Loben und den Zentralkomplex verzweigen. Der αPeaTYR1-CPL3 Antikörper markierte die Plasmamembran von transfizierten HEK293-Zellen. Die Lokalisierung von Rezeptor und Ligand deuten darauf hin, dass Tyramin die optische und olfaktorische Wahrnehmung beeinflussen könnte. / Biogenic amines form a group of substances which play an important role in the endocrine system of invertebrates and vertebrates. They bind to specific receptors of the G-protein coupled type. In this work two new receptors from Periplaneta americana were cloned. By several approaches two full-length cDNA sequences were obtained. The amino acid sequence is very similar to known tyramine receptors of Locusta/Bombyx or dopamine receptors from Apis/Drosophila, respectively. Therefore they were named PeaTYR1 and PeaDOP2. Residues which are important for forming the binding pocket, activation of the receptor or G-protein coupling could be identified in both receptors. Sequence alignments group them together with other tyramine receptors or insect-type dopamine receptors. The corresponding mRNA can be detected in different tissues by RT-PCR. One aim of this work was the preparation of a polyclonal antiserum against PeaTYR1. This serum detects several bands in a brain homogenate; one has the calculated mass of PeaTYR1. Its specificity was proven by praeabsorption. On brain slices the serum labels large regions in the protocerebrum, but also fine structures in the antennal lobes, the optic lobes or the central complex. Another serum against tyramine labels several cell clusters, which ramify within the optic lobes and the central complex. On transfected HEK293 cells the receptor can be detected on the plasma membrane. The localization of receptor and ligand may indicate a role of tyramine in optical/olfactory perception.
4

Source, topography and excitatory effects of GABAergic innervation in cockroach salivary glands

Blenau, Wolfgang, Rotte, Cathleen, Witte, Jeannine, Baumann, Otto, Walz, Bernd January 2009 (has links)
Cockroach salivary glands are innervated by dopaminergic and serotonergic neurons. Both transmitters elicit saliva secretion. We studied the distribution pattern of neurons containing gamma-aminobutyric acid ( GABA) and their physiological role. Immunofluorescence revealed a GABA-immunoreactive axon that originates within the subesophageal ganglion at the salivary neuron 2 (SN2) and this extends within the salivary duct nerve towards the salivary gland. GABA-positive fibers form a network on most acinar lobules and a dense plexus in the interior of a minor fraction of acinar lobules. Co-staining with anti-synapsin revealed that some putative GABAergic terminals seem to make pre-synaptic contacts with GABA-negative release sites. Many putative GABAergic release sites are at some distance from other synapses and at distance from the acinar tissue. Intracellular recordings from isolated salivary glands have revealed that GABA does not affect the basolateral membrane potential of the acinar cells directly. When applied during salivary duct nerve stimulation, GABA enhances the electrical response of the acinar cells and increases the rates of fluid and protein secretion. The effect on electrical cell responses is mimicked by the GABA(B) receptor agonists baclofen and SKF97541, and blocked by the GABAB receptor antagonists CGP52432 and CGP54626. These findings indicate that GABA has a modulatory role in the control of salivation, acting presynaptically on serotonergic and/or dopaminergic neurotransmission.
5

DIFFERENTIAL GENE EXPRESSION IN PERIPLANETA americana IN RESPONSE TO IMMUNIZATION WITH BEE PHOSPHOLIPASE A2

Clyne, Erin Michele 11 October 2001 (has links)
No description available.
6

DIFFERENTIAL GENE EXPRESSION IN <i>PERIPLANETA AMERICANA</i> IN RESPONSE TO IMMUNIZATION WITH BEE PHOSPHOLIPASE A2

Clyne, Erin M. 11 October 2001 (has links)
No description available.
7

Caractérisation des sous-types de récepteurs nicotiniques neuronaux d'insectes et étude de la modulation de leurs profils pharmacologiques par les insecticides néonicotinoïdes / Subtypes characterization and pharmacological profiles modulation study of insect nicotinic receptors by neonicotinoid insecticides

Cartereau, Alison 26 September 2018 (has links)
L’utilisation intensive des insecticides pour lutter contre les insectes ravageurs de culture et vecteurs demaladies, a conduit à des polémiques sur le mode d’action des insecticides. Ces polémiques sont liéesau fait que le mode d’action des insecticides, notamment des néonicotinoïdes est mal connu. Ils agissentprincipalement sur les récepteurs à l’acétylcholine (ACh) de type nicotinique (nAChR) qui jouent un rôlefondamental dans la transmission synaptique cholinergique. Bien que ces récepteurs soient bien décritschez les mammifères, très peu d’études ont évalué l’effet des néoniotinoïdes sur un récepteur natifd’insecte.Au cours de cette thèse, nous avons pour la première fois exprimé en ovocytes de xénope un récepteurhomomérique ⍺7 de blatte et étudié ces propriétés pharmacologiques vis-à-vis des néonicotinoïdes,comparativement au récepteur a7 de rat. Nos résultats révèlent un récepteur atypique qui est insensibleà l’⍺-bungarotoxine et qui n’est pas activé par les néonicotinoïdes. Ainsi, bien que les gènes codantpour les sous-unités α7 de blatte et de rat forment un groupe monophylétique distinct des autres sousunitésd’insectes et de mammifères, les récepteurs homomériques obtenus semblent avoir despropriétés pharmacologiques différentes. Parallèlement, nous avons étudié les propriétéspharmacologiques des nAChR natifs et notamment l’effet modulateur d’un pyréthrinoïde, la permethrine,sur les courants induits par le dinotefurane. Ce travail a permis d’évaluer le mode d’action d’unantiparasitaire, le Vectra 3D. Enfin, nous avons également entrepris de développer la techniqued’extraction membranaire afin de l’utiliser comme alternative pour étudier le mode d’action desinsecticides.Pour conclure, cette thèse a permis une avancée sur l’étude de la caractérisation des propriétéspharmacologiques des récepteurs nicotiniques neuronaux des insectes et sur l’étude du mode d’actiondes insecticides néonicotinoïdes. / The intensive use of insecticides against crop pests and vectors of human and animal leads to several polemics about their mode of action. All these controversies are related to the fact that the mode of action of insecticides in insects is poorly unknown, in particular neonicotinoids which act on nicotinic acetylcholine (ACh) receptors (nAChR).During this PhD thesis, we characterized for the first time the pharmacological properties of a cockroach ⍺7 homomeric receptor in a xenopus oocyte. Our results revealed that cockroach ⍺7 in an atypical receptor that is insensitive to ⍺-bungarotoxin and not activated by neonicotinoids. Cockroach and rat ⍺7 receptors which are included in the same cluster have distinct pharmacological properties. We then studied the pharmacological properties of native receptors, in particular, the modulatory effect of permethrin on dinotefuran-induced currents. This work was included in the study of Vectra 3D. We also evaluated the use of insect central nervous system membrane extraction as a strategy to study the pharmacological properties of insect native nAChRs.To conclude, this PhD contribute to the study of the pharmacological properties of insect nAChRs and the study of the mode of action of neonicotinoids insecticides.
8

Desenvolvimento de metarhizium anisopliae em ninfas de periplaneta americana durante a invasão / Development of metarhizium anisopliae in periplaneta americana nymphs during the invasion

Machado, João Antônio Rangel 27 March 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-28T11:21:35Z No. of bitstreams: 2 Dissertação - João Antônio Rangel Machado - 2015.pdf: 4325578 bytes, checksum: 74553bf431f6100c4577eec10eec4143 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-28T11:25:06Z (GMT) No. of bitstreams: 2 Dissertação - João Antônio Rangel Machado - 2015.pdf: 4325578 bytes, checksum: 74553bf431f6100c4577eec10eec4143 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-10-28T11:25:06Z (GMT). No. of bitstreams: 2 Dissertação - João Antônio Rangel Machado - 2015.pdf: 4325578 bytes, checksum: 74553bf431f6100c4577eec10eec4143 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-03-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The susceptibility of cockroaches to infection with pathogenic fungi can be associated to the host species and their stage/instar. The high resistance of elder nymphs of Periplaneta americana, a synanthropic species in tropical and subtropical regions, against Metarhizium anisopliae is still poorly understood and can be connected to behavioral, physiological and mechanical mechanisms. Fourth and fifth instar nymphs (N4 or N5), treated topically with conidia, removed mechanically part of the conidia from the cuticle, antennae and legs, immediately after treatment and in the following days. A small number (< 5%) of the conidia on the cuticle germinated in the first 24 hours, and quantitative germination of the remaining conidia reached 80% within the next 7 days. In most of the treated nymphs, the fungus failed to reach the hemolymph during the 10 days of the test, and in the others, the number of hyphal bodies ranged from 500 to 8 x 107 per μL hemolymph. Few nymphs (30%) died within 10 days after inoculation, and M. anispoliae developed in 50% of the cadavers. The results confirmed the high resistance of elder P. americana nymphs to M. anisopliae and highlighted the importance of the early stages of the infection during the contact and insect invasion by the fungus. Subsocial behavior patterns and specific physiological factors in the cuticle, not elucidated in this study, are resistance key issues and need to be considered when developing mycoinsecticides for P. americana and other cockroach control. / A susceptibilidade de baratas à infecção com fungos entomopatogênicos parece ser ligada a espécie hospedeira e estágio/estádio. A resistência elevada de ninfas mais velhas de Periplaneta americana, uma espécie sinantrópica em regiões tropicais e subtropicais, para Metarhizium anisopliae ainda está pouco entendida e pode ser ligada a mecanismos comportamentais, mecânicos e fisiológicos. Ninfas de quarto e quinto ínstar (N4 ou N5) tratadas topicamente com conídios removeram mecanicamente parte dos conídios da cutícula com as antenas e patas imediatamente após tratamento e nos próximos dias. Um número reduzido (< 5%) dos conídios na cutícula germinou nas primeiras 24 horas, e a germinação quantitativa dos conídios restantes chegou até 80% nos próximos 7 dias. Na maioria das ninfas tratadas, o fungo não conseguiu chegar na hemolinfa durante os 10 dias do teste, e nas outras, o número de corpos hifais variou entre 500 e 8 x 107 por μl de hemolinfa. Poucas ninfas (30%) morreram até 10 dias após inoculação, e M. anispoliae desenvolveu em 50% dos cadáveres. Os resultados confirmaram a grande resistência de ninfas mais velhas de P. americana para M. anisopliae e ressaltaram a importância das fases iniciais da infecção durante o contato e invasão do inseto pelo fungo. Padrões de comportamento subsocial e fatores fisiológicos específicos na cutícula, não esclarecidos nesse estudo, são questões chave de resistência e precisam ser considerados no desenvolvimento de micoinseticidas para controle de P. americana e de outras baratas.
9

CARACTERISATION DE LA B-GLYCOSIDASE DE LA BLATTE PERIPLANETA AMERICANA : APPLICATION A LA VALORISATION DES GLYCOALCALOÏDES DE LA POMME DE TERRE EN DECOMPOSITION / CHARACTERIZATION OF BETA-GLUCOSIDASE FROM COCKROACH, PERIPLANETA : AMERICANA APPLICATION TO THE VALORIZATION OF GLYCOALCALOIDS FROM DECAYED POTATOES

Koffi, Grokore yvonne 10 November 2016 (has links)
La pomme de terre produit des glycoalcaloïdes comme la plupart des Solanacées. Deux composés, en particulier, l’α-solanine et l’α-chaconine, sont produits en plus grande quantité lorsque le tubercule est exposé à la lumière et subit des dégradations. Ces molécules sont toxiques et peuvent représenter un danger pour le consommateur et des nuisances pour l’environnement. Dans le cadre de cette thèse, les teneurs en α-solanine et α-chaconine dans la chaire de pomme de terre verdie, en germination ou en décomposition retrouvées sur les marchés d’Abidjan (Côte d'Ivoire) ont été analysées. Les résultats ont montré que la chaire de ces pommes de terre contient des quantités élevées de ces deux composés, dépassant 2 à 5 fois la limite recommandée. Pour des raisons de sécurité sanitaire, ces pommes de terre doivent être proscrites de l’alimentation humaine. En revanche, la teneur élevée en glycoalcaloïdes dans ces pommes de terre représente une source de solanidine, un précurseur pour la synthèse d'hormones et de composés pharmacologiquement actifs, qui mérite d’être exploitée. Dans cet objectif, nous avons développé une méthode chimio-enzymatique simple, comprenant un traitement acide partiel suivi d’une hydrolyse enzymatique par la β-glycosidase de la blatte Periplaneta americana dont le gène a été isolé à partir d’une librairie génomique de cDNA afin de détoxifier ces composés et produire la solanidine. / Potato produce glycoalkaloids as most plants of Solanaceae family. The principal glycoalkaloids, α-chaconine and α-solanine are produced in greater quantities when potato tubers are exposed to light and are subject to deteriorations. These compounds are toxic and can represent a real danger for the consumer and the environment where they are discharged during their degradation. In this work, the estimation of glycoalkaloids in the flesh of different types of decayed potatoes usually found in different market places of Abidjan (Ivory Coast) was evaluated. The results showed that turned green and also sprouting or rotting potato flesh contain high amounts of toxic solanine and chaconine, exceeding by 2 to 5-fold the recommended limit. For safety consideration, these decayed potatoes should be systematically set aside. The accumulation of α-chaconine and solanine in potatoes can be seen as an attractive source of solanidine that is an important precursor for hormone synthesis and some pharmacologically active compounds. To this end, we proposed herein a simple chemo-enzymatic protocol comprising a partial acidic hydrolysis followed by an enzymatic treatment with the β-glycosidase from Periplaneta americana whose gene was isolated from a cDNA genomic library in order to detoxify these compounds and produce solanidine.
10

Quantification and determination of the interindividual variability observed in a group of cockroaches and its implications at a collective level

Planas-Sitjà, Isaac 10 April 2017 (has links)
In this thesis, we used the American cockroach study the relationship between animal personality and collective behaviour. These questions do not only regard domiciliary cockroaches or insects; in fact, the questions we discuss here have a large scope and concern most of the known gregarious species distributed in several taxa. One of our aims is to develop general tools, methods and analyses that could be used for the study of collective behaviour.We show evidence of personality in several behavioural traits and different contexts in the American cockroach. These behavioural differences were observed in a context without social interactions during the daytime (isolated condition) and nighttime (solitary exploration behaviour) and in a social context (rate of joining a shelter and sheltering time). Based on the short-term experiments, this personality can be understood as differences in the probability of joining a shelter. We show that the behavioural variability existing in a population of domiciliary cockroaches is very high. The composition of personalities within a group can lead to group personality – consistent differences in group behaviour. For instance, groups composed of different behavioural profiles show different collective dynamics. Regarding the long-term experiments, our results show that the individuals that were aggregated at a site that was repeatedly disturbed by a lighting stimulus during their resting period showed slow migration to a new shelter, which allowed the initial aggregation site to remain the site of choice for a few days. Moreover, the disturbance regime did not influence the group's global activity rhythm. At the individual level, we observed interindividual differences (personalities) in terms of their position prior to the disturbance but not for the different steps of the fleeing behaviour itself. In addition, we show that thigmotaxis affects the reaction time to the disturbance: individuals near the walls of the shelter react more slowly thanindividuals in the centre. Finally, an approach coupling modelling and experimental data shows that behavioural variability plays a secondary role during migration dynamics, thus highlighting the plasticity of personality traits depending on the context. / Un des comportements collectifs les plus répandus, qu’il s’agisse de vertébrés (mammifères, oiseaux, poissons), d’insectes ou encore de bactéries, est la tendance des individus à se regrouper. Les causes proximales de ces rassemblements ou agrégats, c'est-à-dire les mécanismes à leur origine, ont retenu moins d’attention que l’étude des causes ultimes. De plus, dans la plupart des études portant sur les processus d’agrégation, notamment chez notre organisme modèle, la blatte, la diversité des comportements individuels est souvent sous-estimée ou ignorée. L’objectif de cette thèse est l’étude du rôle des différences interindividuelles, également connues comme personnalité animale ou syndromes comportementales, dans les processus de prise de décision collective et notamment la formation des agrégats.Pour cela, nous avons utilisé des groupes de mâles de la blatte américaine Periplaneta americana. Ces insectes peuvent s’agréger dans un ou plusieurs abris et présenter des différences dans leur réponse au milieu, aux conspécifiques et dans le partage de l’information. Dans le cadre de prises de décisions collectives, nous avons mis en évidence une personnalité individuelle mais également au niveau du groupe. Celles-ci se manifestent dans la recherche d’un abri dont certains individus jouent un rôle clef. Nous avons montré que les groupes présentent une stabilité qui est observable au niveau de la dynamique d'agrégation et qui dépend de la distribution des personnalités au sein de ceux-ci. De plus, nous remarquons que ces différences de personnalités au sein des groupes affectent la prise de décision collective, notamment la vitesse du choix et le nombre total d’individus abrités. De manière surprenante, la composition des groupes n’affecte pas la probabilité que ceux-ci atteignent un consensus: la majorité des blattes étant agrégées sous le même abri.Concernant les influences croisées entre l’effet sociale et la personnalité des blattes, nous montrons que les effets sociaux tendent à supprimer les différences inter-individuelles et créent une corrélation entre le comportement de chaque individu et le comportement du groupe. De plus, nous observons que la présence de différentes personnalités dans un groupe augmente les amplifications sociales, celles-ci étant dues aux interactions entre les membres du groupe. Finalement, nous abordons la question du rôle de la personnalité sur le comportement de fuite lors des perturbations lumineuses et sur la dynamique d’émigration quand le site de repos est régulièrement perturbé. Nous avons montré l’existence de personnalités exprimées pendant la phase active nocturne et de différences interindividuelles au niveau du thigmotactisme pendant la journée (phase passive de repos et d’agrégation). Curieusement, ces différences inter-individuelles ne sont pas observées lors du comportement de fuite et au niveau de la dynamique global d’émigration. Dans la dernière partie de notre thèse, nous discutons, en particulier, des synergies et des conflits entre les différentes personnalités et les dynamiques collectives et avançons l’hypothèse que les phénomènes que nous avons mis en évidence sont partagés par de nombreuses espèces grégaires. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

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