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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.
111

Isolamento e localização imunohistoquímica de apirase de galha globosa de Calliandra brevipes BENTH (Fabaceae: Mimosoidae) usando anticorpos contra NTPDases e seu domínio B conservado

Quellis, Leonardo Ramos January 2013 (has links)
Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-08-31T15:40:53Z No. of bitstreams: 0 / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-09-01T11:35:40Z (GMT) No. of bitstreams: 0 / Made available in DSpace on 2017-09-01T11:35:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2013 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Por alinhamento das sequências de aminoácidos da apirase de S. tuberosum e isoformas de outras espécies de plantas, alta identidade (46% a 94%) e similaridade (64% a 96%) foram identificadas entre elas, incluindo espécies diferentes de Fabaceae, e estreita relação estrutural foi encontrada entre os domínios B destas proteínas. Anticorpos policlonais anti-apirase de batata S. tuberosum inibiram 65-80% da atividade catalítica desta proteína. Soros imunes policlonais produzidos contra os peptídeos sintéticos homólogos potB1LJ, LbB1LJ e SmB1LJ ou potB2LJ, LbB2LJ e SmB2LJ, derivados de domínios B de isoformas de NTPDases, inibiram significativamente (32-44%) a atividade da apirase de batata. Estes anticorpos podem ser ferramentas moleculares auxiliares para o estudo das isoformas de apirase. A atividade apirásica de tecidos de folha (NL) ou caule (NS) normais e de galha globosa (GG) de Calliandra brevipes BENTH (Fabaceae: Mimosoidae) foi testada em meio de reação pH 7,5 e na presença de C12E9, e a hidrólise de ADP, UDP ou GDP por GG foi 1,8 a 2,4 vezes maiores que tecidos não galhados. Anticorpos policlonais anti-apirase de batata inibiram significativamente (70-90%) a hidrólise de ATP, ADP, GDP ou UDP por NS. Em GG, similarmente, a atividade ATPásica, GDPásica, ADPásica ou UDPásica foi significativamente inibida (40-66%). Para o isolamento e identificação de apirase de tecidos normais e galha globosa de Calliandra brevipes, amostra de tecido de NS ou NL não galhado, ou de GG previamente homogeneizada em Triton X-100 mais deoxicolato de sódio foi fracionada em gel não desnaturante contendo os mesmos detergentes. Usando ADP como o substrato, a atividade catalítica da enzima permitiu o aparecimento de uma única banda de precipitado de fosfato de cálcio mostrando idêntica mobilidade eletroforética nas amostras NS, NL e GG, sendo mais intensa nesta última, sugerindo que a apirase é superexpressa neste tecido. Nesta banda de maior mobilidade, distintos polipeptídeos de 52 a 75 kDa foram reconhecidos pela imunoreatividade cruzada de anticorpos anti-apirase de batata, sugerindo a existência de formas ativas da mesma proteína com diferentes cargas líquidas, possivelmente como um resultado de diferentes níveis de glicosilação. Além disso, uma banda de aproximadamente 52 kDa, de menor mobilidade e atividade, foi também identificada em todos os tecidos, possivelmente a apirase em sua forma completamente deglicosilada. Usando técnicas histoquímicas e microscopia óptica, cortes micrométricos corados por lugol ou azul de astra-safranina evidenciaram a câmara pulpal amplamente circundada por tecido nutritivo contendo amido em sua porção distal, e parênquima cortical delimitado por anéis esclerenquimáticos lignificados. Por técnicas histoquímicas, a atividade ADPásica ou ATPásica foi encontrada como um depósito eletrodenso granular de fosfato de chumbo distribuído na superfície externa, e nos tecidos nutritivos da galha globosa. Por técnicas imunohistoquímicas, usando Microscópio Confocal de Varredura a Laser e anticorpos anti-apirase de batata e anti-peptídeos sintéticos, a apirase de galha globosa foi encontrada nos mesmos sítios. Hipóteses funcionais para esta proteína estão sob investigação. Além disso, o tempo de germinação de semente de C. brevipes foi determinado, e no quinto dia após a instalação do teste, a primeira folha foi aberta, identificando tecidos de crescimento rápido apropriados para a investigação da regulação da hidrólise de ATP por apirase na proliferação celular. / By alignment of amino acid sequences of the S. tuberosum apyrase and isoforms from other plant species, high identity (46 to 94%) and similarity (64 to 96%) were identified between them, including distinct species of Fabaceae, and closer structural relationship was found between the domains B from these proteins. Polyclonal antibodies anti- S. tuberosum potato apyrase inhibited 65-80% of the catalytic activity of this protein. In addition, polyclonal immune sera produced against homologue synthetic peptides potB1LJ, LbB1LJ and SmB1LJ or potB2LJ, LbB2LJ and SmB2LJ, derivatives from B domains of NTPDases isoforms, significantly inhibited (32 to 44%) potato apyrase activity. These antibodies could be useful molecular tools for studies of the apyrase isoforms. The apyrase activity from the non-galled stem (NS), non-galled leaf (NL), or globose gall (GG) tissue from Calliandra brevipes BENTH (Fabaceae: Mimosoidae) was tested in reaction medium pH 7.4 and in the presence of C12E9, the ADP, UDP or GDP hydrolysis by GG was 1.8 to 2.4 fold higher than non-galled tissues. Polyclonal antibodies anti-potato apyrase significantly inhibited (70 to 90%) the ATP, ADP, GDP or UDP hydrolysis by NS. In GG, similarly, the ATPase, GDPase, ADPase or UDPase activity was also significantly inhibited (40-66%). For isolation and identification of apyrase from normal tissues and globose gall from the Calliandra brevipes, sample of NS, NL or GG tissue was previously homogenised in Triton X-100 plus sodium deoxycholate, and fractionated in non-denaturing gel containing the same detergents. Using ADP as the substrate, the enzyme catalytic activity gave rise to the appearance of a single calcium phosphate precipitate band displaying identical electrophoretic mobilities in NS, NL, and GG samples, being more intense in this last one suggesting that apyrase is over-expressed in this tissue. In this band of higher mobility, a number of distinct polypeptides ranging from 52 to 75 kDa were recognized by cross-immunoreactivity with polyclonal anti-potato apyrase antibodies, suggesting the existence of active forms of the same protein with different net charges, possibly as a result of distinct glycosylation levels. In addition, an immunoreactive band of approximately 52 kDa, of lower mobility and activity, was also identified in all tissues, possibly apyrase in completely deglycosylated form. By histochemical techniques and light microscopy, micrometric sections stained with lugol or Astra Blue-Saphranine evidenced the chamber pulpal widely surrounded by nutritive tissue containing starch in its distal portion, and cortical parenchime delimited by rings sclereides lignified. By histochemical techniques, the ADPase or ATPase activity was found as a granular dense lead phosphate deposit distributed at the external surface, and inside of the nutritive cells of the globose gall. By immunohistochemical techniques, using confocal laser scanning microscopy and antibodies anti-potato apyrase and anti-synthetic peptides, the gall globose apyrase was found at same sites. In addition, the time of laboratory germination of C. brevipes seed was determined, and on the fifth day after test installation, the first leaf opened, identifying rapid growing tissues suitable for further investigations on the participation of both apyrase and regulation of ATP hydrolysis in cell proliferation.
112

Investigating the Driving Mechanisms Behind Differences in Bleaching and Disease Susceptibility Between Two Scleractinian Corals, Pseudodiploria Strigosa and Diploria Labyrinthiformis

Pratte, Zoe A 15 June 2015 (has links)
Disease and bleaching are two conditions which commonly lead to coral death. Among coral species, susceptibility to disease and bleaching is variable, and Pseudodiploria strigosa tends to be diseased more than Diploria labyrinthiformis, while D. labyrinthiformis bleaches more readily. The focus of this dissertation was to investigate and compare multiple components of these two coral species, and identify how they may relate to disease and bleaching resistance. Compenetnts examined included the surface mucopolysacharide layer (SML) thickness, gene expression, microbial associates, and a white plague aquarium study. The SML thickness decresased with increasing temperature regardless of coral species, indicating that SML thickness does not likely play a role in differences between susceptablities of these two coral species. However, Diploria labyrinthiformis had a lower mortality rate at 31°C, had fewer differentially expressed genes assossiated with stress, and upregulated genes associated with innate immunity in the summer, all of which may contribute to its relative disease resistance. The bacterial associates of each coral species were also monitored. Differences between the two coral species were primarily caused by Clostridia, Gammaproteobacteria, and rare species which may contribute to the relatively higher disease susceptibility of P. strigosa. Lastly, an aquarium study suggested that a potential pathogen of the Roseobacter clade infects both D. labyrinthiformis and P. strigosa, and might be transmitted by the Cryptochiridae gall crab, indicating that potential disease vectors associated with these two coral species may also play a role in disease resistance and resilience.
113

Evaluation der sonographischen Gallenblasenwanddicke als neuer nicht-invasiver Marker für das Vorliegen von Ösophagusvarizen / Evaluation of the gall bladder wall thickening as new, non-invasive screening parameter for esophageal varices

Tsaknakis, Birgit 21 October 2020 (has links)
No description available.
114

Substantivkomposita und Sinngebung im Kontext frühmittelalterlicher Wissensvermittlung : Eine kulturanalytisch-linguistische Untersuchung zur Wortbildung bei Notker III

Raag, Nicolaus Janos January 2016 (has links)
This thesis approaches the question of how nominal compounds as linguistic means contribute to the construction of cultural meaning within the framework of knowledge transfer in the medieval monastic school. The starting point for the study is the semiotic definition of culture, which sees culture as shared models for perceiving, relating and interpreting among members of a social group. Language is seen as the place where cultural meaning is constructed and manifests itself in significant patterns, i.e., patterns of language usage that have meaning due to the fact that they are patterns. The central objective of this study is to reveal such patterns in nominal compounds drawn from Old High German (or rather bilingual hybrid) adaptations of Latin school texts translated, or adapted by Notker III (Labeo). Focus is placed on newly formed compounds, as well as compounds that differ distinctively from their Latin models. Methodologically this study combines the morphosemantic analysis of nominal compounds with a hermeneutic approach interpreting compounds in their textual and cultural context. Three significant patterns were established: (1) explication of implied meaning, (2) summary of complex expressions, and (3) explanatory translation. The first pattern can be observed in cases where the power of compounds to give additional information was utilised, e.g., in order to ensure a certain interpretation of a metaphorical expression. The second pattern demonstrates the capacity of compounds to refer to more complex concepts, expressing underlying syntactic constructions in a more memorisable manner. Finally, recourse was taken to explanatory translation in order to make the concept easier to understand. The three patterns are not necessarily the only patterns used by Notker III (Labeo); rather they are to be seen as an exemplification of the potential of nominal compounds for meaning construction.
115

Total St Gall : Medieval Monastery as a Disciplinary Institution

Jezierski, Wojtek January 2010 (has links)
How much was a medieval monastery reminiscent of a modern prison? Or insane asylum? And if it was in the least - what can such a metaphor tell us about power relations structuring the life of medieval monks? The purpose of this compilation thesis (sammanläggningsavhandling) is to render explicit and analyze relations of power and modes of control comprising the social tissue of early medieval Benedictine monasteries. By bringing up the examples of tenth- and eleventh-century monasteries of St Gall, Fulda, and Bury St Edmunds, this thesis seeks to understand what power was in medieval monasteries, how and between whom it was exercised, what and how it affected in terms of collective and individual identity. The thesis consists of three introductory chapters, four previously published empirical articles, and a concluding remarks section. Article 1 investigates the problem of surveillance and patterns of social control dispersed in the monastery of St Gall. Article 2 studies the early and high medieval institutional expectations and means of enforcement of the monk’s role. Article 3 scrutinizes an example of a persecution process and a set of defense measures in the hands of the St Gall community warding off an unwanted visitor. Article 4 examines a number of internal monastic conflicts from several monasteries and strategies, both political and cognitive, guiding them. In investigating these problems, the thesis proceeds in a manner of deliberate anachronism. It asks questions about how human subjectivity was manufactured in early medieval St Gall, what were a medieval monastery’s ‘conditions of possibility’ to operate as a social regime, or oral and literary means of conflict management etc. The crucial modern social theories on which the thesis hinges are: Erving Goffman’s notion of ‘total institution’, and Michel Foucault’s analysis of power, as well as Pierre Bourdieu’s logic of action.
116

Metabolism and pathogenicity in the phytopathogen Rhodococcus fascians / Métabolisme et pathogénicité chez le phytopathogène Rhodococcus fascians

Forizs, Laetitia 10 February 2012 (has links)
Rhodococcus fascians is a Gram-positive phytopathogenic bacterium which induces the development of leafy galls, local amplifications of multiple buds, on most infected plants. This process is linked to the production of phytohormones along with the presence of essential virulence-associated genes like the plasmid loci att and fas and the chromosomal gene vicA. However, the presence of these genes is not sufficient to ensure the infection phenotype development, indicating that other genes play a role in R. fascians pathogenicity. In this work, we studied the metabolic modifications occurring when the bacterium interacts with its host using a proteomic approach. A comparison between virulent and avirulent strains showed variations in the expression of catalases. In the virulent strain, besides the transitory induction of the att locus expression, the bacterium changes its metabolism from the Krebs cycle to the glyoxylate shunt, a process which is frequently observed in bacteria confronted to a hostile environment. The expression of the shunt-specific enzyme isocitrate lyase increased, while expression of fumarate hydratase and pyruvate dehydrogenase decreased. Hence, we focused on the link between the glyoxylate shunt and virulence. A screening of a R. fascians mutant library based on the capacity of bacteria to use acetate as the sole carbon source, a metabolic pathway depending on the glyoxylate shunt, resulted in the identification of a new gene essential for R. fascians pathogenicity. This gene encodes a glycosyl transferase, an enzyme known to be involved in the bacterial cell wall biosynthesis but possibly also implicated in cytokinin secretion. A mutant in this gene harboured an altered colony phenotype and could not induce malformations on infected plants. Accordingly, our results were integrated in the leafy gall pathology model recently presented by Stes et al. (2011). Finally, the several questions that are raised by this work, allowed us to suggest further research perspectives in order to unveil a little more of the R. fascians mysterious ways to interact with the plant./Rhodococcus fascians est une bactérie Gram-positive phytopathogène qui induit le développement de galles feuillées, des amplifications locales de multiples bourgeons, sur la plupart des plantes infectées. Ce processus est lié à la production de phytohormones ainsi qu’à la présence de gènes essentiels associés à la virulence tels que les loci plasmidiques att et fas et le gène chromosomique vicA. Cependant, la présence de ces gènes ne suffit pas à garantir le développement du phénotype d’infection, indiquant que d’autres gènes jouent un rôle dans la pathogénicité de R. fascians. Dans ce travail, nous avons étudié les modifications métaboliques qui se produisent lorsque la bactérie interagit avec son hôte par une approche protéomique. Une comparaison entre les souches virulente et avirulente a mis en évidence des variations d’expression au niveau des catalases. Dans la souche virulente, outre l’induction transitoire de l’expression du locus att, la bactérie change son métabolisme pour passer du cycle de Krebs au shunt du glyoxylate, un processus fréquemment observé chez les bactéries confrontées à un environnement hostile. L’expression de l’isocitrate lyase, enzyme spécifique au shunt, augmente, tandis que celle de la fumarate hydratase et de la pyruvate déhydrogénase diminue. Nous nous sommes donc intéressés au lien entre le shunt du glyoxylate et la virulence. Le screening d’une banque de mutants de R. fascians basé sur la capacité de la bactérie à utiliser l’acétate comme seule source de carbone, une voie métabolique dépendant du shunt du glyoxylate, a permis d’identifier un nouveau gène essentiel pour la pathogénicité de R. fascians. Ce gène code pour une glycosyl transferase, une enzyme impliquée dans la biosynthèse de la paroi bactérienne mais également dans la sécrétion des cytokinines. Un mutant dans ce gène présente un phénotype de colonie altéré et ne peut induire de malformations chez les plantes infectées. Finalement, nos résultats et les pistes d’interprétations que nous avons émisent nous permettent de compléter le modèle de l’interaction R. fascians-plante proposé récemment par Stes et al. (2011). Des perspectives de recherches visant une meilleure compréhension de ce pathosystème sont proposées. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
117

La cécidomyie orange du blé, Sitodiplosis mosellana (Géhin): appréhension des risques et gestion intégrée / Orange wheat blossom midge, Sitodiplosis mosellana (Géhin): risk evaluation and pest management

Jacquemin, Guillaume 03 April 2014 (has links)
La cécidomyie orange du blé, Sitodiplosis mosellana (Géhin), est un ravageur commun du froment. Présente sur les trois continents de l’hémisphère Nord, cette espèce est connue depuis deux siècles mais son contrôle reste difficile tant par sa présence discrète que par ses effectifs hautement variables. En Wallonie, les niveaux d’infestations sont globalement faibles mais atteignent localement des seuils inquiétants.<p>Au début des années 2000, la phéromone sexuelle de S. mosellana a été identifiée au Canada. Cette découverte a permis la fabrication de pièges qui ont considérablement amélioré la détection et la mesure des vols de cet insecte minuscule. De 2007 à 2010, les captures de S. mosellana ont été mesurées quotidiennement dans plusieurs dizaines de champs de Wallonie, aux historiques et aux couverts variés.<p>Les volumes de captures au piège à phéromone sexuelle ont été très importants. Il a fallu en étudier la signification, notamment en termes de mesure du risque. En effet, si les mâles sont efficacement capturés, seules les femelles constituent un risque de dégâts. L’interprétation correcte des captures à l’aide de ce type de piège, a été rendue possible par l’observation de différences fondamentales concernant la mobilité et la distribution spatiale des mâles et des femelles de S. mosellana. Même s’ils ne mesurent pas directement l’émergence proprement dite, les pièges à phéromone ont permis, grâce à leur très grande sensibilité, de préciser les connaissances sur l’émergence des adultes et de révéler que plusieurs vagues d’émergence pouvaient se succéder au cours d’une même année.<p>La prévision des émergences de la cécidomyie orange du blé, constitue la clé de voûte de la lutte contre ce ravageur dont un contrôle efficace par des insecticides ne se justifie éventuellement que lorsque la courte saison des pontes coïncide avec l’épiaison des froments. Les patrons d’émergence obtenus par les pièges ont été confrontés aux prévisions de différents modèles conçus en Europe ou en Amérique du Nord, et appliqués aux conditions météorologiques observées de 2007 à 2010. Aucun de ces modèles n’a prévu correctement les émergences sur l’ensemble des quatre années.<p>Les données d’émergence obtenues à l’aide des pièges à phéromone (effectifs élevés et relevés quotidiens) ont fait apparaître une relation de cause à effet entre, d’une part les vagues d’émergences et, d’autre part les épisodes pluvieux observés trois à six semaines plus tôt. L’écart entre une &61618;pluie inductrice&61618; et la vague d’émergence induite correspondante s’est avéré constant en termes d’accumulation de température :il équivaut à 160 degrés-jours en base 7°C. Partant de ce constat et des acquis des modèles antérieurs, un modèle prévisionnel original des émergences a été développé et validé sur le terrain. Allié à une meilleure connaissance de la biologie du ravageur, il constitue un outil majeur de la lutte intégrée.<p>Par ailleurs, les travaux menés ont également révélé l’existence d’un biais fréquent dans les essais d’évaluation des variétés, entraîné par la concentration des pontes de cécidomyie orange sur les premières parcelles atteignant le stade épiaison. Dans le système d’évaluation en vigueur, notamment pour l’inscription dans les catalogues nationaux, ce biais conduit à une sous-estimation du potentiel de rendement des variétés de blé les plus précoces.<p>Enfin, la découverte du rôle inducteur des pluies sur l’émergence des adultes a été exploitée en conditions contrôlées pour planifier des émergences échelonnées, et pour disposer, pendant une longue période, de jeunes adultes prêts à pondre. Cette application permet dès à présent de mesurer en serre le niveau de résistance des variétés exposées de façon homogène à l’insecte, quel que soit leur degré de précocité.<p>De diverses façons, cette étude contribue à une meilleure connaissance de la cécidomyie orange du blé et offre de nouveaux outils pour la lutte intégrée contre ce ravageur.<p><p>--------------------------------------------------<p><p>The orange wheat blossom midge, Sitodiplosis mosellana (Géhin), a common pest of wheat throughout the northern hemisphere, is known for two centuries but remains difficult to control due to its discrete behavior and its highly variable population level.<p>In general, the infestation levels in Wallonia (Belgium) are low, although levels could locally exceed worrying thresholds. <p>In the early 2000s, the sexual pheromone of S. mosellana has been identified in Canada. This discovery has led to the manufacturing of traps which have greatly improved the detection of this tiny insect. From 2007 to 2010 in Wallonia, S. mosellana captures have been daily registered in about 20 fields with different cropping histories and grown with different crops.<p>Insect captures by pheromone traps were numerous. Relation between amount of captures and risk measurement has been studied. As expected, only the males are attracted by the pheromone and the risk of ears infestation is mainly related to the presence of females. The correct interpretation of captures in pheromone traps has been established by the observation of fundamental differences between males and females concerning their mobility and their spatial distribution. <p>Despite the fact that pheromone traps are not real emergence traps, they have led to new information on adult emergence indicating that several emergence waves can be consecutive during the same year. <p>Forecasting the emergence of the adult orange wheat blossom midge is a key element on pest management. Insecticides treatments are sometimes justified when the egg laying period of the insect coincides with ear emergence of wheat. Emergence patterns established from captures of pheromone traps have been compared with the forecast of several models built in Europe or North America. These forecasting models were used with the meteorological data observed from 2007 until 2010. None of the six tested models provided a reliable forecast across the four years of our study. <p>Emergence data from catches in pheromone traps were very accurate because the number of catches were high and were taken each day. This emergence data showed a relation between emergence waves and rainfalls occurring during the preceding 3 to 6 weeks. The lag between inductive rain and emergence wave is constant in terms of temperature accumulation: it is equivalent to 160 degree–days above 7°C. This discovery, combined with experience from previous models, was incorporated into a new forecasting model.<p>In addition, the present work has also revealed the existence of a common bias in variety evaluation trials leading sometime to the concentration of the eggs in the earliest earing variety. In the current evaluation system, this bias leads to a sub-evaluation of the yield for the most precocious varieties. <p>Finally, the discovery of the inductive rain for adult emergence has been used in the screening for resistant varieties to S. mosellana by providing adults during the complete duration of the test. This application of the model allows to measure, under controlled conditions, the level of resistance of all varieties (early and late heading varieties) which are exposed homogeneously to the insect.<p>In total, this study has contributed to a better understanding of the orange wheat blossom midge and provides some new tools in the management of this pest.<p> / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished
118

Moving Lines: The Anthropology of a Manuscript in Tudor London

Preston, Andrew S. 16 September 2014 (has links)
No description available.
119

La fumigation biologique comme alternative au bromure de méthyle pour le contrôle du nématode Méloïdogyne incognita dans la production de concombre dans les serres / The use of biofumigation crops as an alternative to Methyl Bromide for the management of the root-knot nematode in greenhouse cucumber production

Haroutunian, Garabed 25 March 2013 (has links)
Les nématodes à galles demeurent l'un des problèmes les plus graves des ‎agriculteurs de serres du Liban et du Moyen-Orient. Dans le passé, la fumigation du sol au ‎bromure de méthyle a été considérée comme la meilleure mesure de contrôle contre ces ‎nématodes. Toutefois, à la lumière de l'élimination globale du bromure de méthyle, l'accès ‎aux alternatives efficaces et durables est devenu une nécessité essentielle.‎L'objectif de cette étude est d'évaluer l'efficacité des deux engrais verts, le radis ‎huileux (Raphanus sativus oleifera) et à la roquette (Eruca vesicaria sativa) appliquées ‎avec ou sans bâche en plastique, séparément et en combinaison avec Oxamyl, dans la ‎gestion des nématodes à galles en cultures de concombres de serre. En outre, cette étude ‎vise à évaluer la faisabilité financière de la technique de biofumigation avec les deux ‎cultures utilisées et de la rentabilité finale de ces engrais verts en termes de taux coût-profit ‎par rapport au bromure de méthyle.‎A cette fin, trois expériences sur le terrain ont été menées dans des serres ‎commerciales, situées sur la zone côtière du Liban.‎Dans les deux expériences A et B, des résultats cohérents ont été enregistrés en ‎termes de production de rendements significativement plus élevés et de la réduction des ‎populations de nématodes avec les engrais verts‎ utilisés avec ou sans bâche en plastique, ‎par rapport au témoin non traité.‎Quant aux résultats obtenus par les engrais verts‎ par rapport ‎ au bromure de ‎méthyle, dans l'expérience A, le rendement produit par le bromure de méthyle était ‎significativement plus élevé que celui du radis huileux avec bâche en plastique. ‎Cependant, la différence n'était pas significative entre la réduction de la population de ‎nématodes résultant du bromure de méthyle et celle du radis huileux avec bâche en ‎plastique. Les différences du rendement ainsi que la réduction des nématodes étaient ‎significatives entre le bromure de méthyle et le radis huileux sans bâche en plastique.‎Dans l'expérience B, aucune différence significative n'a été observée dans le ‎rendement ni la réduction de la population de nématodes entre aucun des deux engrais ‎verts‎ utilisés avec bâche en plastique et le bromure de méthyle. Ces différences étaient ‎significativement en faveur du bromure de méthyle uniquement lorsque le radis huileux a ‎été utilisé sans bâche en plastique.‎Dans l'expérience C, où Vydate (Oxamyl) a été appliqué à la dose de 1 litre par 1,000 ‎m2 à tous les traitements, il n'y avait pas de différence significative dans le rendement ni la ‎réduction de la population de nématodes entre chacun des deux engrais verts utilisés avec ‎ou sans bâche en plastique et le bromure de méthyle.‎L'analyse coût-profit menée sur tous les traitements appliqués dans les 3 ‎expériences a montré que dans tous les cas, tous les traitements appliqués, qu'ils soient ‎chimiques, non-chimique (avec ou sans bâche en plastique) ou en association ont produit ‎des bénéfices nets supérieurs au bromure de méthyle, même lorsque le rendement produit ‎par le bromure de méthyle était significativement plus élevée.‎L'utilisation du plastique pour couvrir les radis huileux a généralement produit de ‎meilleurs résultats en termes de production de rendements plus élevés, une meilleure ‎réduction des populations de nématodes à galles dans le sol, ainsi conduisant à des ‎augmentations raisonnables des profits nets.‎A la base de ces résultats et à la lumière de l'élimination globale du bromure de ‎méthyle, on peut conclure que l'utilisation du radis huileux et la roquette comme engrais ‎verts avec bâche en plastique peut être considéré comme un outil alternatif pour la gestion ‎des nématodes à galles dans la production de concombres de serre dans les conditions ‎libanaises.‎ / Root-knot nematodes remain one of the most serious problems faced ‎by ‎greenhouse farmers of Lebanon and the Middle East region. In the past, soil fumigation ‎with methyl bromide has been considered as ‎the best control measure against root-knot ‎nematodes. However, in the light of the global phase out of methyl bromide, finding ‎efficient and viable alternatives is an essential necessity.‎The objective of this study is to evaluate the efficacy of the two biofumigation ‎crops ‎Oil Radish (Raphanus sativus oleifera) and Arugula (Eruca vesicaria sativa) applied ‎with ‎and without plastic tarp, separately and in combination with Oxamyl in the ‎management of ‎the root-knot nematodes in greenhouse cucumber crops. Additionally, this ‎study aimed at ‎assessing the financial feasibility of the biofumigation technique with the ‎two cops used ‎and the final profitability of these green manure crops in terms of cost to ‎benefit ratio as ‎compared to methyl bromide.‎For this purpose, three field experiments were carried out in ‎commercial ‎greenhouses situated on the coastal zone of Lebanon.‎In both experiments A & B consistent results were recorded in terms of production ‎of ‎significantly higher yields and reduction of nematode population with the ‎biofumigation ‎crops used whether with or without plastic cover, as compared to untreated ‎fallow.‎As to the results achieved by the biofumigation crops with respect to methyl ‎bromide, ‎in experiment A yield produced by methyl bromide was significantly higher than ‎oil radish ‎with plastic cover. However, no significant difference was found between ‎reduction of ‎nematode population resulting from methyl bromide and oil radish with plastic ‎cover. ‎Difference was significant between methyl bromide and oil radish without plastic ‎cover in ‎both yield and reduction of nematodes.‎In experiment B no significant difference was observed in neither yield nor ‎reduction ‎of nematode population between any of the two biofumigation crops used with ‎plastic ‎cover and methyl bromide. These differences were significantly in favor of methyl ‎bromide ‎only when oil radish was used without plastic cover.‎In experiment C where Vydate (Oxamyl) was incorporated at the rate of 1 liter ‎per ‎‎1,000 m2 to all treatments, there was no significant difference in neither yield nor ‎reduction ‎of nematode population between any of the two biofumigation crops used with or ‎without ‎plastic cover.‎Cost-benefit analysis made on all treatments applied in the 3 experiments ‎showed ‎that in all cases, all treatments applied, whether chemical, non-chemical (with or ‎without ‎plastic cover) or in combination have produced higher net profits than methyl ‎bromide, ‎even when yield produced by methyl bromide was significantly higher.‎Use of plastic for covering oil radish has generally produced ‎better results in terms ‎of ‎production of higher yields, better reduction of soil ‎populations of root-knot nematodes‏‎ ‎and ‎‏leading to ‎‏reasonable increases of net profits.‎Based on these findings and in the light of global phase out of methyl bromide, ‎it ‎can be concluded that the use of oil radish and arugula as biofumigation crops with ‎plastic ‎cover can be considered as ‎an alternative management tool for the root-knot ‎nematode in ‎greenhouse cucumber ‎production under Lebanese conditions.‎
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In vitro-Versuche mit dem Polo like-Kinase 1 Hemmstoff BI 2536 an Zelllinien von Gallenwegskarzinomen

Thrum, Stephan 25 February 2014 (has links) (PDF)
Karzinome der Gallenwege sind mit einer schlechten Prognose assoziiert. Eine potentiell kurative chirurgische Resektion ist bei der Mehrzahl der Patienten aufgrund des späten Zeitpunkts der Diagnosestellung nicht möglich, so dass derzeit vorrangig palliative Therapieansätze Anwendung finden. Das nur geringe Ansprechen auf konventionelle Radio- oder Zytostatikatherapie begründet die Notwendigkeit neuer Therapieansätze. Einen möglichen Angriffspunkt stellt hierbei die Polo-like-Kinase 1 (Plk1) dar, da ihre zentrale Rolle in der Regulation des Zellzyklus zunehmend erkannt und eine vermehrte Expression in malignem Tumorgewebe verglichen mit gesundem Gewebe nachgewiesen wurde. Das Dihydropteridinon BI 2536 ist ein poten-ter, niedermolekularer und selektiver Hemmstoff der Plk1 und sollte daher auf seine Wirksamkeit an Gallenwegskarzinomen untersucht werden. In der vorliegenden Arbeit konnte gezeigt werden, dass BI 2536 die untersuchten 14 Zelllinien von Gallenblasen- und Gallengangskarzinomen wirkungsvoll hemmt. Das Ansprechen unterschied sich zwischen den Zelllinien und ordnet sich vergleichbar zu Veröffentlichungen an anderen malignen Tumoren ein. Die Expression von Plk1 und dessen assoziierten Transkriptionsfaktor FoxM1 konnte bei Westernblot-Versuchen bei allen Zelllinien nachgewiesen werden, was eine Bedeutung in der Onkogenese vermuten lässt. Die Behandlung mit BI 2536 beeinflusste jedoch die Proteinmenge beider nicht. An für die folgenden Versuche ausgewählten drei Zelllinien zeigten sich in der reversen Transkription mit anschließender Echtzeit-Polymerase-Kettenreaktion (qRT PCR) ähnliche Ergebnisse in Bezug auf die exprimierte mRNA von Plk1. Westernblot-Analysen ermittelten keine signifikanten Veränderungen der an wichtigen intrazellulären Kaskaden beteiligten Proteine p42/44 und Akt sowie deren phosphorylierten Formen. Obwohl die Proteinmenge des Mitosemarkers Phospho-Histon H3 ebenso unverändert blieb, führte die Behandlung mit BI 2536 – dies zeigen Ergebnisse der Durchflusszytometrie – zu einer signifikanten, dosisabhängigen Zunahme der G2/M Fraktion des Zellzyklus und Zunahme der Apoptose-rate. Der maximale Hemmeffekt in der Behandlung von BI 2536 lag bei einer Inkubations-dauer von vier Tagen. Die Empfehlungen aus den klinischen Studien der Phase II von BI 2536 sowie dem Ziel der Vermeidung von Resistenzen ergibt sich die Notwendigkeit von Kombinationsversuchen mit Zytostatika, die in einer anderen Phase des Zellzyklus angreifen. Die in der Behandlung von Gallenwegskarzinomen etablierten Antimetaboliten 5-Fluorouracil und Gemcitabin wurden hierzu ausgewählt und es zeigten sich für 5 Fluorouracil synergistische, für Gemcitabin hingegen additive Kombinationseffekte. Zusätzlich wurde die Wechselwirkung mit dem IGF 1-Rezeptor-Inhibitor NVP-AEW541 untersucht, der ebenfalls einen neuen Behand-lungsansatz in der Krebstherapie darstellt und bei Gallenwegskarzinomen in vitro wirksam ist. Auch hier zeigen sich synergistische Effekte, die jedoch erst in höheren Behandlungs-dosen auftraten. Die Ergebnisse dieser Arbeit zeigen, dass die Hemmung der Plk1 bei Gallenblasen- und Gallengangskarzinomen einen wirksamen Behandlungsansatz darstellt. Auf der Grundlage der in dieser Arbeit beschriebenen Ergebnisse wird eine weitere präklinische und klinische Testung von selektiven Plk1-Hemmstoffen wie BI 2536 an Gallenwegskarzinomen empfohlen.

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