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Regionalism som motstånd : Två latinamerikanska staters motiv att ingå i integrationsprojektet ALBA / Regionalism as resistance : Two Latin American states' motives to participate in the project of integration ALBAScott, David January 2009 (has links)
<p>The formation of sovereign states in regional blocks has become an essential feature in the world system. Therefore, the purpose of this paper is to investigate which motives and driving forces that affect the creation of projects of regional integration outside Europe and the Western World. By choosing the Latin American project of integration ALBA (<em>the Bolivarian Alliance of the Americas</em>) as a case of regional integration outside Europe and the Western World, the study investigates the motives expressed by the most prominent actors of the project, Venezuela and Cuba. ALBA is chosen as a representative and a unique case and through the consumption of the gramscian and the realist approaches, the essay defines two motives that affect the creation of projects of regional integration. As a way of investigating the actors’ motives, the paper studies political statements, especially those of the Venezuelan president Hugo Chávez, and official positions expressed in central documents and declarations. The result shows that the motives behind ALBA are to promote a regionalism that gives priority to social welfare issues and to use this regional organization to create a multipolar world system. The essay concludes, with ALBA as a case, that the fundamental motives that could govern the regional integration process outside Europe and the Western World are, firstly, the will to resist a hegemonic world order that doesn’t give priority to social welfare issues and, secondly, to resist a unipolar world system and work as a “balancer”. While this applies to Venezuela, there are in the case of Cuba certain self-interests that could serve as motives. However, the study can’t rule out that also other motives can exist, but there is no evidence that can be used to prove that in this paper.</p>
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Functional Characterization of PtaRHE1, a gene that encodes a RING-H2 type protein in poplar/Caractérisation fonctionnelle de PtaRHE1, un gène qui code pour une protéine de type RING-H2 chez le peuplier.Mukoko Bopopi, Johnny 14 January 2011 (has links)
SUMMARY
PtaRHE1 is a poplar (Populus tremula x P. alba) gene encoding a REALLY INTERESTING NEW GENE (RING) domain-containing protein. RING proteins are largely represented in plants and play important roles in the regulation of many developmental processes as well as in plant-environment interactions. In this thesis, we present a functional characterization of PtaRHE1. To gain further insight into the role of this gene, molecular and genetic alteration approaches were used. The results of in vitro ubiquitination assays indicate that PtaRHE1 protein is a functional E3 ligase and this activity was shown to be specific with the human UbCH5a, among the tested ubiquitin-conjugating enzymes. Histochemical GUS stainings showed that the PtaRHE1 promoter is induced by plant pathogens and by elicitors such as salicylic acid and cellulase and is also developmentally regulated. In silico predictions and the transient expression of PtaRHE1-GFP fusion protein in N. tabacum epidermal cells revealed that PtaRHE1 is localized both in the plasma membrane and in the nucleus. The localization of expression of PtaRHE1 in poplar stem by in situ hybridization indicated that PtaRHE1 transcripts are localized within the cambial zone mainly in ray cells, suggesting a role of this gene in vascular tissue development and/or functioning. The overexpression of PtaRHE1 in tobacco resulted in a pleiotropic phenotype characterized by a curling of leaves, the formation of necrotic lesions on leaf blades, growth retardation as well as a delay in flower transition. Plant genes expression responses to PtaRHE1 overexpression provided evidence for the up-regulation of defence and/or programmed cell death (PCD) related genes. Moreover, genes coding for WRKY transcription factors as well as for MAPK, such as WIPK, were also found to be induced in the transgenic lines as compared to the wild type (WT). Taken together, our results suggest that the E3 ligase PtaRHE1 plays a role in the signal transduction pathways leading to defence responses against biotic and abiotic stresses. Identification of PtaRHE1 target(s) is required in order to fully assess the role of this E3 ligase in the ubiquitination-mediated regulation of defence response./
RÉSUMÉ
PtaRHE1 est un gène qui code pour une protéine possédant un domaine RING (REALLY INTERESTING NEW GENE) chez le peuplier (Populus tremula x P. alba). Les protéines de type RING sont très répandues chez les végétaux où elles jouent de rôles importants dans la régulation de plusieurs processus de développement et également dans les interactions plantes-environnement. Dans le cadre de ce travail, nous avons procédé à la caractérisation fonctionnelle du gène PtaRHE1. Dans le but de découvrir la fonction de ce gène, nous avons adopté une stratégie faisant usage d’approches moléculaires ainsi que de l’altération de l’expression génique. Les résultats obtenus montrent que la protéine PtaRHE1 est une E3 ligase et que cette activité enzymatique est spécifique à l’Ubiquitin-Conjugating enzym humaine UbCH5a. Les résultats du test histochimique GUS ont montré que le promoteur du gène PtaRHE1 est induit par des pathogènes et aussi par l’acide salicylique et la cellulase. Par ailleurs, ce promoteur est aussi régulé au cours du développement végétal. Les prédictions in silico et l’expression transitoire d’une fusion traductionnelle GFP-PtaRHE1, au niveau de l’épiderme des feuilles du tabac N. tabacum, ont révélé que la protéine PtaRHE1 se situe tant au niveau de la membrane cytoplasmique qu’au niveau du noyau. La localisation de l’expression du gène PtaRHE1, par les techniques d’hybridation in situ, montre que les transcrits de ce gène se retrouvent principalement au niveau des cellules de rayon, dans la zone cambiale, suggérant que ce gène pourrait jouer un rôle dans le développement ou la formation du tissu vasculaire. La surexpression du gène PtaRHE1 chez le tabac a conduit à l’obtention d’un phénotype pléiotropique caractérisé par un recroquevillement (incurvation) des feuilles, la formation des lésions nécrotiques sur le limbe, un retard de croissance ainsi qu’un retard dans la transition florale. L’analyse de la réponse de l’expression de différents gènes à la surexpression de PtaRHE1 a mis en évidence l’induction des gènes liés à la défense et ou à la mort cellulaire programmée. En outre, l’expression des gènes codant pour des facteurs de transcription WRKY et aussi des MAPKs, tel que WIPK, était aussi plus élevée chez les plantes transgéniques comparées au type sauvage. Les résultats de ce travail suggèrent que PtaRHE1, comme E3 ligase, pourrait jouer un rôle dans la transduction des signaux cellulaires conduisant aux réactions de défense contre les stress biotiques et abiotiques. L’identification de la (des) cible(s) de PtaRHE1 est indispensable pour la compréhension du rôle de cette protéine dans la régulation des réponses de défense par l’intermédiaire de l’ubiquitination.
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Activation Tagging as a Powerful Tool for Gene Discovery in PoplarHarrison, EDWARD 11 1900 (has links)
Our understanding of tree growth and development has increased substantially in the last few decades and is expected to increase much more as we fully exploit newly developed genomic tools. A major milestone in tree genomics was the sequencing of the entire genome of Populus trichocarpa, and the realization that we understand the function of very few of the 45,000 predicted genes in this genome. To advance our knowledge of gene function in Populus, we have created the largest population of mutant poplars to date which will enable us to link altered phenotypes with genes that are responsible. This thesis describes this mutant population, provides preliminary results on the complexity of mutants identified and examines one distinct mutant called shriveled leaf. These results clearly demonstrate the power of this population for gene function analysis and reveal that this population will be a valuable genomic resource for tree biotechnology for many years to come. / Thesis (Master, Biology) -- Queen's University, 2008-01-31 16:09:03.458
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Effect of basella alba and hibiscus macranthus on tm4 sertoli cell functionsOpuwari, Chinyerum January 2009 (has links)
<p>Basella alba (BA) and Hibiscus macranthus (HM) are used by traditional healers in Cameroon to treat male sexual fertility problems. Previous studies showed that in vivo administration of the leaf extracts of both plants caused a significant increase in rat seminal vesicle weight and spermatozoa numbers was accompanied by a significant increase in serum testosterone. The aim of this study was to establish the effects of BA and HM extracts on Sertoli cell functions. TM4 cell line was used in this study as it exhibited properties similar to the Sertoli cells (Mather, 1982). Sertoli cell play a key role in spermatogenesis by regulating and supporting germ cell development. Therefore, any alterations in Sertoli cell physiology or structure may lead to impaired spermatogenesis, germ cell loss and male infertility. Developing germ cells in the seminiferous tubule require a constant supply of lactate and pyruvate (Jutte et al, 1981 / 1982) and toxicant induced alterations in these nutrients have been shown to induce germ cell necrosis (Monsees et al., 2000). TM4 Sertoli cells were cultured in DMEM/Ham F-12 (M) for one day and exposed to<br />
0.01, 0.1, 1, 10, 100 &mu / g/ml of BA and HM extracts, respectively, for four further days. The extracts were dissolved in 0.5 % DMSO in M, while 0.5 % and 2% DMSO in M were used as negative or positive controls, respectively, and 100mM ethanol as positive control where indicated. Results obtained from the Sertoli cells exposed to BA extracts, showed that the plant extract had no significant effect on the cell viability but induced a significant concentration-dependent increase in lactate (19-67%) and pyruvate levels (39-102%) and a concentration-dependent decrease in the protein content (9-42%). The H& / E histological study confirmed that the BA extract had no cytotoxic effect, as there were no changes in the morphology of the cell. Likewise, apoptotic study using DAPI showed no alteration in the nucleus when compared to the negative control. The HM plant extract significantly enhanced mitochondrial dehydrogenase activity (7fold) in the Sertoli cells but caused only slight alterations in the lactate and pyruvate levels. There was no effect seen in the protein content of the Sertoli cells. H& / E and DAPI staining revealed that there were neither changes in the morphology of the cells nor any alteration regarding the mitotic and apoptotic indices. Thus, the HM extract did not have a cytotoxic effect on the cells. This study demonstrated that the Basella alba methanol extract may enhance spermatogenesis as it stimulated the source of energy required for the development of germ cells without exerting a cytotoxic effect. The Hibiscus macranthus extract stimulated mitochondrial dehydrogenase activities and may thus trigger changes in Sertoli cell physiology. In summary, both plant extracts enhanced certain Sertoli cell<br />
functions and thus might explain the positive in vivo effects of the combined plant extracts on rat spermatogenesis observed by Moundipa et al. (1999).</p>
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Etude des déterminants de la vulnérabilité à la cavitation du xylème chez les peupliersAwad, Hosam 23 September 2011 (has links) (PDF)
Les modèles climatiques prédisent pour le futur une accentuation de la fréquence et de l'intensité des épisodes de sécheresse, ce qui affecterait sérieusement les écosystèmes forestiers. En conséquence, il y a une demande croissante pour du matériel végétal plus résistant à la sécheresse, et pour la compréhension des mécanismes génétiques et physiologiques de la tolérance des arbres à la sécheresse. Dans des conditions de sécheresse, la tension dans les vaisseaux du xylème augmente, et la cavitation peut se produire causant une embolie du vaisseau qui devient alors non fonctionnel. La vulnérabilité du xylème à la cavitation est corrélée à la tolérance à la sécheresse, indiquant l'importance de ce caractère pour la tolérance à la sécheresse. Cependant, peu était connu sur la variabilité de ce caractère au niveau intra-spécifique et ses bases génétiques étaient inconnues. Dans un premier temps, nous avons démontré que la vulnérabilité à la cavitation du xylème de peuplier (Populus tremula x Populus alba) s'acclimate à des conditions de sol plus sec et que ceci s'accompagne de changements dans la structure du xylème et d'expressions géniques. Ce processus d'acclimatation appuie l'hypothèse du rôle important joué par la vulnérabilité du xylème à la cavitation dans la tolérance à la sécheresse. Dans un second temps, nous avons étudié les bases structurales et génétiques de la vulnérabilité à la cavitation grâce à deux approches. La première a consisté à étudier les changements anatomiques et d'expressions géniques se produisant au cours de l'acclimatation de la vulnérabilité du xylème à la cavitation à des conditions plus sèches. Nous avons déterminé que l'augmentation de la vulnérabilité à la cavitation dans des conditions plus sèches est corrélée à une diminution du diamètre de la paroi de la ponctuation. Nous avons observé des changements d'expression géniques dans des conditions de sécheresse mais ceux ci n'ont pas pu être reliés à un changement de la vulnérabilité à la cavitation. Dans une seconde approche, nous avons utilisé dix lignées de peupliers dont l'expression de gènes impliqués dans le métabolisme de la lignine ont été modifiés et deux lignées surexprimant une pectine méthylestérase (PME) pour examiner le rôle de ces gènes dans la vulnérabilité à la cavitation. Chez les peupliers ayant un métabolisme des lignines modifié, nous avons également testé la relation entre les propriétés hydriques et mécaniques. Nous apportons des preuves que les lignines et les pectines (à travers les PME) sont impliquées dans la vulnérabilité à la cavitation et nos données sur les lignées transgéniques de peupliers ne soutiennent pas un lien exclusif entre les propriétés hydriques et mécaniques.
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Effect of basella alba and hibiscus macranthus on tm4 sertoli cell functionsOpuwari, Chinyerum January 2009 (has links)
<p>Basella alba (BA) and Hibiscus macranthus (HM) are used by traditional healers in Cameroon to treat male sexual fertility problems. Previous studies showed that in vivo administration of the leaf extracts of both plants caused a significant increase in rat seminal vesicle weight and spermatozoa numbers was accompanied by a significant increase in serum testosterone. The aim of this study was to establish the effects of BA and HM extracts on Sertoli cell functions. TM4 cell line was used in this study as it exhibited properties similar to the Sertoli cells (Mather, 1982). Sertoli cell play a key role in spermatogenesis by regulating and supporting germ cell development. Therefore, any alterations in Sertoli cell physiology or structure may lead to impaired spermatogenesis, germ cell loss and male infertility. Developing germ cells in the seminiferous tubule require a constant supply of lactate and pyruvate (Jutte et al, 1981 / 1982) and toxicant induced alterations in these nutrients have been shown to induce germ cell necrosis (Monsees et al., 2000). TM4 Sertoli cells were cultured in DMEM/Ham F-12 (M) for one day and exposed to<br />
0.01, 0.1, 1, 10, 100 &mu / g/ml of BA and HM extracts, respectively, for four further days. The extracts were dissolved in 0.5 % DMSO in M, while 0.5 % and 2% DMSO in M were used as negative or positive controls, respectively, and 100mM ethanol as positive control where indicated. Results obtained from the Sertoli cells exposed to BA extracts, showed that the plant extract had no significant effect on the cell viability but induced a significant concentration-dependent increase in lactate (19-67%) and pyruvate levels (39-102%) and a concentration-dependent decrease in the protein content (9-42%). The H& / E histological study confirmed that the BA extract had no cytotoxic effect, as there were no changes in the morphology of the cell. Likewise, apoptotic study using DAPI showed no alteration in the nucleus when compared to the negative control. The HM plant extract significantly enhanced mitochondrial dehydrogenase activity (7fold) in the Sertoli cells but caused only slight alterations in the lactate and pyruvate levels. There was no effect seen in the protein content of the Sertoli cells. H& / E and DAPI staining revealed that there were neither changes in the morphology of the cells nor any alteration regarding the mitotic and apoptotic indices. Thus, the HM extract did not have a cytotoxic effect on the cells. This study demonstrated that the Basella alba methanol extract may enhance spermatogenesis as it stimulated the source of energy required for the development of germ cells without exerting a cytotoxic effect. The Hibiscus macranthus extract stimulated mitochondrial dehydrogenase activities and may thus trigger changes in Sertoli cell physiology. In summary, both plant extracts enhanced certain Sertoli cell<br />
functions and thus might explain the positive in vivo effects of the combined plant extracts on rat spermatogenesis observed by Moundipa et al. (1999).</p>
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Vergleich von Gastrokolopexie und Antropexie in der Linea alba zur Rezidivprophylaxe nach Torsio ventriculi des HundesFlorian, Stephanie 11 April 2008 (has links) (PDF)
Der Magendilatations-Torsions-Komplex stellt ein akut verlaufendes Syndrom dar. Die Pathogenese umfasst ein multifaktorielles Geschehen und basiert auf einer Vielzahl prädisponierender Faktoren vergesellschaftet mit einem auslösenden mechanischen Moment. Die chirurgische Therapie beinhaltet neben der Reposition des Magens die Durchführung einer Gastropexie, welche auf schnellem, einfachem und komplikationsarmen Weg eine effektive Rezidivprophylaxe realisieren soll. Ziel der vorliegenden Arbeit war der Vergleich zweier Operationsmethoden der Gastropexie hinsichtlich ihrer Praktikabilität, Effektivität sowie den zu erhebenden klinischen Befunden post operationem. Im Hinblick auf beschriebene Prädispositionen verhielten sich die Patienten beider Gruppen gemäß den Angaben der Literatur. Durch die prospektive Durchführung von Gastrokolopexien sollte eine Therapiemodalität untersucht werden, die mit geringem intraoperativen Aufwand eine weitgehend anatomische Position des Magens realisiert. Es wurden 34 Patienten operiert und durch eine telefonische Besitzerbefragung mit Hilfe eines Fragebogens hinsichtlich relevanter gastrointestinaler Symptome aufgearbeitet. Von den 34 Patienten erlitten 12 Tiere ein Rezidiv, so dass eine Rezidivrate von 40% bei einer Mindestbeobachtungszeit von 12 Monaten resultierte. Bei bestimmten Rassen, insbesondere der Deutschen Dogge und dem Hovawart, fielen ein relativ weit nach kranial reichendes, den Magen ohne Spannung überlappendes Kolon, sowie gehäuft Rezidive (7 von 9) auf. Relevante intra- oder postoperative Komplikationen konnten nicht festgestellt werden. Zum Vergleich dienten 100 Patienten mit Antropexie in der Linea alba die gleichermaßen, jedoch retrospektiv aufgearbeitet wurden. Neben 13 Patienten mit Rezidiv (14%, bei einer Mindestbeobachtungszeit von 12 Monaten) ließen sich 4 Tiere mit rezidivierenden Dilatationen beschreiben. Des Weiteren konnten die Vorzüge dieser Therapiemodalität, analog zu der Erstbeschreibung, als einfach, schnell, risiko- und komplikationsarm angesprochen werden. Während die erzielten Resultate nach Antropexie vergleichbar waren mit einer Vielzahl effektiver Methoden mit niedriger Rezidivrate, so stellte sich die Gastrokolopexie signifikant unterlegen dar. Nach Gastrokolopexie wurden keine rezidivierenden Dilatationen beobachtet, allerdings ist die Fallzahl relativ gering. Als Schlussfolgerung ergibt sich, dass die Gastrokolopexie, obwohl sie komplikationsarm ist und gut toleriert wurde, als Rezidivprophylaxe nicht empfohlen werden kann. Grund ist die hohe und vor dem Hintergrund wirksamer Alternativen nicht ak-zeptable Rezidivrate.
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Studien zur Stammbuchpraxis der Frühen Neuzeit Gestaltung und Nutzung des Album amicorum am Beispiel eines Hofbeamten und Dichters, eines Politikers und eines Goldschmieds, etwa 1550 bis 1650 /Schwarz, Christiane, January 2002 (has links)
Thesis (doctoral)--Ludwig-Maximilians-Universität, München, 1999. / Includes bibliographical references (p. 271-302) and index.
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Studien zur Stammbuchpraxis der Frühen Neuzeit Gestaltung und Nutzung des Album amicorum am Beispiel eines Hofbeamten und Dichters, eines Politikers und eines Goldschmieds, etwa 1550 bis 1650 /Schwarz, Christiane, January 2002 (has links)
Thesis (doctoral)--Ludwig-Maximilians-Universität, München, 1999. / Includes bibliographical references (p. 271-302) and index.
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Investigação dos efeitos citotóxico e genotóxico do extrato de salix alba L. análises in vitro, in vivo e histológicas /Terrazas, Peterson Menezes. January 2017 (has links)
Orientador: Edson Luis Maistro / Resumo: A Salix alba L. (SA), popularmente conhecida como Salgueiro Branco, é uma planta utilizada na medicina popular para o tratamento de inflamações crônicas e agudas, infecções, dores, febre, entre outros. A caracterização fitoquímica do extrato da casca desta planta revelou que seu principal componente é a salicina, com uma concentração de 4,94 mg/mL, um precursor do anti-inflamatório ácido acetilsalicílico. Considerando que existem poucos estudos que avaliam a ação tóxica e citotóxica do extrato da SA, o presente estudo foi elaborado visando investigar o potencial citotóxico, genotóxico e mutagênico da SA em células mononucleares do sangue periférico humano e de hepatocarcinoma humano HepG2 in vitro, e em diferentes células de camundongos in vivo, utilizando alguns dos testes tradicionais na área de mutagênese, como o teste do MTT, o Ensaio do Cometa e o Teste do Micronúcleo, bem como a verificação de potencial citotoxicidade por meio de análises histológicas e histoquímicas. Os testes de viabilidade celular e citotoxicidade (azul de tripan e MTT) permitiram a escolha de 3 concentrações do extrato da SA para serem analisadas nos ensaios de genotoxicidade in vitro: 5, 50 e 100 µg/mL. Pelo ensaio cometa com as células mononucleares de sangue periférico, pôde-se observar que as concentrações de 50 e 100 µg/mL acarretaram um aumento estatisticamente significativo de danos no DNA, em comparação ao controle negativo. Já no teste do micronúcleo, as 3 concentrações avaliadas (5, 50 e 1... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Salix alba L. (SA), popularly known as White Willow, is a plant used in folk medicine for the treatment of chronic and acute inflammations, infections, pains, fever, among others. The phytochemical characterization of the bark extract of this plant revealed that its main component is salicin, with a concentration of 4.94 mg/mL, a precursor of the antiinflammatory acetylsalicylic acid. Considering that there are few studies evaluating the toxic and cytotoxic action of SA extract, the present study was designed to investigate the cytotoxic, genotoxic and mutagenic potential of SA bark wood extract in human peripheral blood mononuclear cells and human hepatoma cell line HepG2 in vitro and in different mouse cells in vivo using some of the traditional mutagenesis tests such as the MTT test, the Comet assay and the Micronucleus test, and cytotoxicity in the liver of mice also by histological and histochemical analysis. Cell viability and cytotoxicity tests (trypan blue and MTT) allowed the choice of 3 concentrations of the SA extract to be analyzed in the in vitro genotoxicity assays: 5, 50 and 100 μg/mL. By the comet assay with the peripheral blood mononuclear cells, it was observed that concentrations of 50 and 100 μg/ml resulted in a statistically significant increase in DNA damage, as compared to the negative control. In the micronucleus test, the 3 concentrations evaluated (5, 50 and 100 μg/mL) did not produce significant increases of micronucleated binucleate cells, as well ... (Complete abstract click electronic access below) / Doutor
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