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Prueba de la causalidad y valoración de la evidencia científica en la litigación del cambio climático : aporte del Caso Urgenda vs. HolandaAbarca Lucero, José Miguel January 2017 (has links)
Memoria (licenciado en ciencias jurídicas y sociales) / La judicialización del cambio climático ha aumentado exponencialmente dentro de los últimos años, debido a la lenta reacción de los Estados en tomar las medidas legislativas necesarias para adaptar a la sociedad actual a las exigencias del fenómeno del cambio climático. Uno de los casos más emblemáticos dentro de este nuevo movimiento es el de Urgenda vs Holanda, en donde el Tribunal ordenó al Estado que redujera sus emisiones de GEI en al menos un 25% para el año 2020 respecto a los niveles de 1990, basado en la evidencia científica disponible y en los compromisos internacionales adoptados por el Estado.
Sin embargo, y a pesar del éxito del caso anteriormente mencionado, la mayoría de estos juicios no corren la misma suerte, principalmente por dos grandes problemas: El primero de ellos es la prueba de la causalidad, la que se ve muchas veces obstaculizada debido a la naturaleza difusa del daño ambiental. El segundo problema es la reticencia de los tribunales a aceptar la evidencia científica como argumento válido para imputar responsabilidad o para establecer un deber de cuidado respecto del demandado.
El objetivo de este artículo es, en base al análisis de doctrina especializada y jurisprudencia nacional y comparada, revisar estas dificultades y descubrir sus posibles soluciones, las que van desde la inversión de la carga de la prueba, hasta las presunciones de responsabilidad.
Por otro lado, también se pretende analizar el caso Urgenda vs Holanda con la finalidad de exponer los principales puntos de la sentencia, para luego pasar a la revisión de la prueba de la causalidad y por qué razones fue aceptada la evidencia científica del IPCC en este caso, lo que ha traído como consecuencia un nuevo movimiento de demandas en contra de Estados por razones y con argumentos muy similares a los entregados por la Fundación Urgenda.
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Reconstitution paléoclimatique et paléoenvironnementale au Valanginien (~135 Ma, Crétacé inférieur) : vers une meilleure compréhension des processus locaux versus globaux / Palaeoclimatic and palaeoenvironmental reconstruction of the Valanginian (~135 Ma, Lower Cretaceous) : towards a better understanding local versus global processCharbonnier, Guillaume 10 December 2013 (has links)
L’étage Valanginien est caractérisé dans le registre sédimentaire par une excursion positive des isotopes du carbone (amplitude 1,5-2‰), appelée « Episode Weissert ». Cet événement coïncide avec des changements paléoenvironnementaux et paléoclimatiques majeurs. La formation de la province volcanique ignée du Paraná-Etendeka a été proposée comme principal facteur forçant contrôlant ces changements. Cependant, de récentes études démontrent que l’Episode Weissert précède systématiquement l’activité volcanique. Ainsi, les facteurs déclenchant qui contrôlent ces changements sont encore source de débat. Dans cette étude des analyses cyclostratigraphique, biostratigraphique, minéralogique et géochimique ont été réalisés sur des sites de moyennes et hautes latitudes (coupes d’Orpierre et de La Charce/Arnayon dans le Bassin Vocontien, site 765C dans la plaine abyssale Argo) dans le but (i) d’explorer la dynamique des changements paléoenvironnementaux à l’échelle locale versus globale et (ii) de discuter des possibles facteurs forçant contrôlant l’épisode Weissert. Les processus diagénétiques et sédimentologiques locaux, qui pouvaient modifier le signal paléoclimatique, ont été discuté avant des interprétations paléoenvironnementales. La calibration astronomique de l’épisode Weissert, réalisée sur la coupe d’Orpierre, a permis pour la première fois le calcul de flux détritiques et de nutriments dans le Bassin Vocontien. Ces résultats indiquent de rapides changements climatiques aux moyennes latitudes, marqués par des conditions plus humides pendant l’Episode Weissert et des conditions plus sèches au Valanginien supérieur. En parallèle de nouvelles données géochimiques et minéralogiques, réalisés sur le site ODP 765C, ont été intégrées à une compilation globale de données géochimique et minéralogique sur 23 coupes répartie dans cinq grands environnements. Trois ceintures climatiques latitudinales majeures ont été identifié durant le Valanginien : (i) une ceinture aride dans l’océan proto Nord Atlantique (~15-17°N), (ii) une ceinture climatique subtropical dans la marge NW téthysienne (~25-30°N), et (iii) une ceinture climatique chaude et tempéré aux sites de hautes latitudes (~53°S et ~40 à ~70°N). Il apparaît que durant cette période, des facteurs orbitaux et tectoniques peuvent avoir contrôlé la distribution de ces ceintures et les principaux changements durant l’Episode Weissert. / The Valanginian stage witnesses a positive carbon isotope excursion (amplitude 1.5-2‰) in the sedimentary records, the so-called « Weissert Episode ». This event coincides with major palaeoenvironmental and palaeoclimatic changes. The formation of the Paraná-Etendeka large igneous province has widely been proposed as the major driving force behind these changes. However recent investigations demonstrate that the Weissert Episode precedes the volcanic activity. Thus the driving force(s) behind these changes are still under debate. In the herein study, cyclostratigraphic, biostratigraphic, mineralogical and geochemical analyses have been performed on mid- and high latitudes sites (the Orpierre and Arnayon/La Charce sections in the Vocontian Basin, and the ODP hole 765C in the Argo abyssal plain) in order (i) to explore the dynamic of the local versus global processes in the palaeoenvironmental changes and (ii) to discuss the possible forcing factors behind the Weissert Episode. Local diagenetic and sedimentological processes that might bias the palaeoclimatic signals are highlighted and discussed before any palaeoenvironmental interpretation. The astronomical calibration of the Weissert Episode performed at Orpierre, allowed for the first time, the calculation of detrital and nutrient influxes into the Vocontian basin. They highlight rapid climate changes at mid latitudes, characterized by pronounced humid conditions during the Weissert Event (Early–Late Valanginian transition) and drier conditions in the Late Valanginian. In parallel, new geochemical and mineralogical analyses performed on the ODP hole 765C have been integrated to a global compilation of published geochemical and mineralogical data from 23 sections, located in five depositional environments. Three latitudinal belts have been recognized during the Valanginian : (i) an arid palaeolatitudinal belt in the Proto North Atlantic Ocean (~15–17°N), (ii) a subtropical climatic belt in the Northwestern Tethyan margin (~25–30°N) ; and (iii) a warm temperate palaeoclimatic belt in the high latitudes site (~53°S and ~40 to 70°N). It appears that during this period, both tectonic and orbital factors might have controlled the distribution of the palaeoclimatic belts and the major palaeoenvironmental changes during the Weissert Episode.
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Die Bedeutung genetischer Polymorphismen im Enzym Cytochrom P450 2C9 für Pharmakokinetik und Wirkungen der nichtsteroidalen Antiphlogistika Diclofenac und IbuprofenFreytag, Georg Tobias Heinrich 08 April 2005 (has links)
Die Bedeutung genetischer Polymorphismen im Enzym Cytochrom P450 2C9 für Pharmakokinetik und Wirkungen von Diclofenac und Ibuprofen Es wird angenommen, dass Cytochrom-P450 2C9 die 4’-Hydroxylierung des Nichtsteroidalen Antiphlogistikums Diclofenac und die Hydroxylierung von S-Ibuprofen beim Menschen katalysiert. Es existieren zwei Varianten von Cyp2C9. Deren Auswirkungen auf die Diclofenac- bzw. Ibuprofen-Pharmakokinetik und die Hemmung von Cox-1 und -2 wurde an 21 gesunden Probanden, die sämtliche Kombination der genetischen Varianten *2 und *3 aufwiesen, untersucht. Es zeigten sich keinerlei Hinweise auf eine Einschränkung des Metabolismus von Diclofenac bei heterozygoten und homozygoten Trägern der Cyp2C9-Allele *2 und *3. Darüber hinaus lagen auch die Serumkonzentrationen des Metaboliten 4’-OH-Diclofenac bei Trägern der Allele Cyp2C9 *2 und *3 nicht niedriger. Obwohl verschiedene in vitro-Untersuchungen Cyp2C9 als metabolisierendes Enzym identifizierten, ist die Pharmakokinetik von Diclofenac ist beim Menschen entweder überhaupt nicht oder nur in geringem Ausmaß von Cyp2C9-Aminosäurenpolymorphismen abhängig. Möglicherweise sind die Auswirkungen der Cyp2C9-Aminosäurenvarianten substratabhängig, oder es ist in vivo ein anderes Enzym als Cyp2C9 verantwortlich für die Bildung von 4’-OH-Diclofenac. Im Unterschied dazu hing die Pharmakokinetik von razemischem und von S-Ibuprofen vom Cyp2C9 *3-Polymorphismus ab. Die Bildung von Tx B2 (Cox-1) hing signifikant von Cyp2C9 *3-Polymorphismus ab, derselbe Trend ließ sich auch für Pg E2 (Cox-2) beobachten. Die eingeschränkte Clearance von S-Ibuprofen, die mit einer erhöhten pharmakodynamischen Aktivität einhergeht, legt nahe, dass Träger des Allels Cyp2C9*3 ein höheres Risiko tragen, nach Einnahme einer oralen Standarddosis unerwünschte Nebenwirkungen zu erleiden. / Consequences of genetic polymorphisms in Cytochrome P450 2C9 for pharmacokinetics and effects of Diclofenac and Ibuprofen. Cytochrome-P450 2C9 is considered to catalyse the 4’-hydroxylation of the nonsteroidal analgesic drug diclofenac and the hydroxylation of S-ibuprofen in humans. There are two variants of Cyp2C9. Their impact on diclofenac/ ibuprofen pharmacokinetics and on the inhibition of cyclooxygenases 1 and 2 was studied in 21 healthy volunteers with all combinations of the Cyp2C9 variants *2 and *3. Blood concentrations of diclofenac/ racemic ibuprofen (and of S-ibuprofen and R-ibuprofen) were measured by HPLC. Thromboxane B2 and prostaglandin E2 were measured with use of an enzyme immunoassay. There was no evidence of impaired metabolism of diclofenac in heterozygous and homozygous carriers of the Cyp2C9 alleles *2 and *3 compared to the wildtype. Furthermore, plasma concentrations of the metabolite 4’-OH-diclofenac were not lower in carriers of Cyp2C9*2 and *3. Marked diclofenac mediated inhibition of Cox-1- and Cox-2 activity was detected in all individuals without any Cyp2C9 genotype dependent differences. Even though several in vitro studies identified Cyp2C9 as the metabolising enzyme, Diclofenac pharmacokinetics in humans is either not or only to a minor extend dependent on the Cyp2C9 amino acid polymorphisms. It may be that the Cyp2C9 amino acid variants have differential effects depending on the substrates. Alternatively, an enzyme other than Cyp2C9 may be responsible for 4’-OH-Diclofenac formation in vivo.In contrast, the pharmacokinetics of racemic and of S-ibuprofen depended on the Cyp2C9 *3-polymorphism. The Cyp2C9 variant *2 exhibited no significant effect. Formation of Tx B2 (cox-1) depended significantly on the Cyp2C9 polymorphism, the same trend was observed for Pg E2 (cox-2). The reduced S-ibuprofen total clearance accompanied by increased pharmacodynamic activity indicates an increased risk for carriers of Cyp2C9*3 to suffer from adverse effects after intake of a standard oral dose.
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IInfluência do Pegivirus humano (HPgV) na medula óssea: impacto clínico e tropismo viral / Human Pegivirus (HPgV) influence on bone marrow: clinical impact and viral tropismDias, Juliana Zanatta de Carvalho 01 February 2019 (has links)
O HPgV (Pegivirus Humano), conhecido anteriormente por GBV-C, causa infecção assintomática, persistente e com alta carga viral. Sendo o vírus de RNA sem patologia associada mais prevalente no mundo até os dias de hoje, os estudos in vitro ainda não foram capazes de mimetizar a replicação in vivo, permanecendo pouco esclarecidos vários aspectos de sua biologia. Estudos em macacos mostraram que os órgãos responsáveis pela maior replicação viral são o baço e a medula óssea, no entanto as células específicas permissíveis à infecção ainda não foram determinadas. Na década de 90, o HPgV ganhou notoriedade por diminuir os efeitos patológicos do HIV e aumentar a sobrevida de pacientes coinfectados HIV/HPgV, através da diminuição da ativação do sistema imune. Devido a essa característica, diversos estudos tentaram associar a presença de viremia a doenças hematológicas e um deles mostrou que a viremia de HPgV parece estar associada com o desenvolvimento de linfoma não- Hodgkin, porém muitas variáveis de confusão parecem influenciar esse resultado. Em conjunto, os dados mostram que o HPgV pode ter influência sobre a maturação e liberação de células progenitoras da medula óssea e, portanto, tornou-se primordial avaliar o impacto da viremia em pacientes com doenças hematológicas e definir o tropismo viral. Para tanto, o presente trabalho analisou a dinâmica de exposição à viremia de HPgV em pacientes submetidos ao transplante de células-tronco hematopoiéticas (HSCT), em cadáveres autopsiados pelo Sistema de Verificação de Óbitos da Capital de São Paulo (SVOC-SP) e em pacientes submetidos à cirurgia de artroplastia pelo Instituto de Ortopedia e Traumatologia (IOT) do HCSP. A carga viral de HPgV foi mensurada por qRT-PCR em Tempo Real levando em consideração valores adquiridos com um curva padrão desenvolvida para este trabalho. Para os pacientes HSCT, o efeito da presença de viremia antes e após o procedimento foi avaliada quanto aos principais desfechos do transplante: doença enxerto-hospedeiro aguda (aGVHD), recaída da doença hematológica primária e mortalidade. Para amostras SVOC e IOT, células específicas dos tecidos (cérebro, fígado, baço, linfonodo, medula óssea e sangue) foram avaliadas quanto à quantidade de RNA viral de polaridade positiva e negativa, a fim de quantificar a replicação e definir o tropismo do vírus. Os resultados mostraram que a prevalência de HPgV encontrada nos pacientes HSCT foi maior do que em estudos similares: 42% para as amostra pré- HSCT e 31% para as amostras pós-HSCT; porém, para as amostras SVOC, a prevalência foi menor do que o esperado: 1,2%. A presença de alta carga viral de HPgV em pacientes HSCT foi associada com aumento da taxa de incidência de aGVHD (95% CI 1,05-5,37, p=0,038). Dada a alta prevalência de HPgV na população brasileira, é essencial confirmar esse achado em outras coortes, de modo a determinar se o monitoramento do HPgV pode beneficiar o cuidado a esses pacientes. Nas amostras SVOC e IOT, a medula óssea apresentou maior número de populações celulares com replicação viral, com destaque para as células B progenitoras e para as células dendríticas. Porém, devido às condições da coleta e do processamento das amostras, o tipo celular permissível à infecção não pôde ser identificado com clareza, portanto fazendo-se necessária a coleta de um número maior de amostras SVOC / HPgV (Human Pegivirus), previously known as GBV-C, causes asymptomatic, persistent and high viral load infection. To date, it is the most prevalent RNA virus without associated pathologies in the world, yet in vitro studies have not yet been able to mimic the in vivo replication, consequently many aspects of its biology remaining unclear. Studies in non-humam primatas have shown that the organs responsible for the greatest viral replication are spleen and bone marrow, however the specific cells permissible for infection have not yet been determined. In the 1990s, HPgV gained notoriety by decreasing the pathological effects of HIV and increasing the survival of coinfected HIV/HPgV patients, by decreasing the activation of the immune system. Because of this characteristic, several studies have attempted to associate the presence of viremia with haematological diseases, and one has shown that HPgV appears to be associated with the development of non-Hodgkin\'s lymphoma, but many confounding variables still seems to influence this outcome. Together, the data show that HPgV may influence the maturation and release of bone marrow progenitor cells and therefore it has become crucial to evaluate the impact of HPgV viremia in patients with haematological diseases and to define viral tropism. Therefore, the present study analyzed the dynamics of HPgV viremia exposure in patients submitted to hematopoietic stem cell transplantation (HSCT), in cadavers autopsied by the São Paulo City Death Verification System (SVOC-SP) and in patients submitted to arthroplasty surgery by the Orthopedics and Traumatology Institute (IOT) of the Clinics Hospital of Sao Paulo. The HPgV was identified by real-time qRT-PCR and the viral load quantification was estimated by a standard curve developed for this work. For HSCT patients, the effect of viremia before and after the procedure was evaluated for the main transplant outcomes: acute graft vs host disease (aGVHD), relapse of primary haematological disease and mortality. For SVOC and IOT samples, tissue-specific cells (brain, liver, spleen, lymph node, bone marrow and blood) were evaluated for the amount of viral positive and negative RNA strains, in order to quantify replication and define virus tropism. The results showed that the prevalence of HPgV found in HSCT patients was higher than in similar studies: 42% for pre-HSCT samples and 31% for post-HSCT samples; however, for SVOC samples, the prevalence was lower than expected: 1.2%. The presence of high viral load of HPgV in HSCT patients was associated with an increase in the incidence rate of aGVHD (95% CI 1.05-5.37, p = 0.038). Given the high prevalence of HPgV in the Brazilian population, it is essential to confirm this finding in other cohorts, in order to determine if HPgV monitoring can improve the care of these patients. In the SVOC and IOT samples, the bone marrow presented a higher number of cell populations with viral replication, especially the progenitor B cells and the dendritic cells. However, due to the conditions of specimen collection and processing, the major permissible cell could not be clearly identified, thus making it necessary to collect a larger number of SVOC samples
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The british Conservative Party under Margaret Thatcher's leadership : conservatism seen from within / Le parti conservateur britannique sous le leadership de Margaret Thatcher : le conservatisme vu de l’intérieurSalem, Manel 08 December 2017 (has links)
Cette thèse aborde le sujet du conservatisme britannique, notamment le conservatisme de1979 jusqu’à 1990, la période qui correspond aux mandats de Margaret Thatcher. Ce travail vise à démontrer que la continuité a été l’aspect déterminant du parti conservateur depuis les XVIIIe et XIXe siècles. Les valeurs premières du conservatisme ont continué à être appliquées avec l’avènement de Margaret Thatcher au pouvoir même si elle incarnait, pour beaucoup de gens, le changement. Ceci apparait dans les discours que Margaret Thatcher tenait quand elle était leader de l’opposition. Le changement était nécessaire selon elle car la société britannique était stagnante. En effet, Thatcher ne pouvait pas accepter ce qu’elle considérait comme étant une « société oisive ».Dès son jeune âge, elle avait appris que travailler dur était à la fois une responsabilité et un plaisir. Ce plaisir-là émane des principes d’indépendance et de persévérance auxquels elle a toujours cru très profondément. Dans ce sens, le changement signifie essentiellement la remise en question du consensus de l’après-guerre, conçu pour aider le pays et ses habitants à se reconstruire. Margaret Thatcher était déterminée à démanteler la social-démocratie keynésienne qui avait imprégné la politique britannique depuis la Seconde Guerre mondiale à cause des circonstances changeantes. L’originalité de sa politique réside dans l’abandon du consensus de l’après-guerre largement basé sur l’état providence et l’intervention de l’état ainsi que l’encouragement des membres de la société à être autonomes et indépendants en plus d’une économie forte et capable de s’autoréguler sans avoir besoin d’intervention de la part du gouvernement. La liberté, l’individualisme et l’autonomie sont les conséquences ultimes de la dérégulation. Ces valeurs étaient les valeurs premières du conservatisme et leur application durant les années quatre-vingt n’étaient que retour au vieux parti conservateur. La continuité du parti conservateur, qui a été interrompue par le keynésianisme du parti travailliste, a été alors rétablie. Pour prouver de cette continuité, un nombre de documents d’archives ont été étudiés au Churchill Archives Centre à Cambridge; des archives telles que les procès-verbaux des réunions du parti conservateur et les discussions qui se sont déroulées entre conservateurs. Par ailleurs, savoir comment les conservateurs eux-mêmes définissent le conservatisme britannique élucide la nature du conservatisme. Pendant longtemps, le parti conservateur a été considéré comme étant le parti monolithique par excellence. Mais le retour en force d’autres partis, comme le parti travailliste après la Seconde Guerre mondiale, a poussé les conservateurs à réfléchir davantage, à innover, à créer des thinks tanks et à ne plus avoir peur d’exprimer leurs opinions diverses. Désormais, ils ne craignent plus le changement, partant du principe que « les choses doivent changer pour qu’elles restent identiques » (The Leopard by Giuseppe Tomasi di Lampedusa). Une large partie de cette thèse porte sur la politique économique. La variable de la politique économique constitue peut-être le critère de réussite le plus visible notamment du fait qu’il est aisément quantifiable, et révèle que l’économie a toujours été une priorité chez les conservateurs. Selon Margaret Thatcher par exemple, le keynésianisme de l’après-guerre avait échoué et devait être abandonné. Pour Thatcher, le problème majeur à résoudre n’était pas le chômage mais l’inflation. La dichotomie entre continuité et changement sera analysée non seulement dans les discours publics de Margaret Thatcher mais aussi dans les discussions internes du parti conservateur. La pléthore de définitions et opinions pose également la question de l’héritage de la dame de fer, à travers son successeur John Major et des événements contemporains tels que le Brexit. / This thesis focuses on the dynamics of continuity and change within the Conservative Party from 1979 to 1990, the period of Margaret Thatcher’s premierships. The aim of this thesis is to demonstrate that continuity had been the defining feature of the Conservative Party since the 18th and 19th centuries. The implementation of the primary values of early Conservatism continued with the advent of M. Thatcher to power although she represented, for many people, the epitome of change. This was all the more obvious in Margaret Thatcher’s public speeches when she was Leader of the Opposition. Change was, to her, necessary since British society was stagnant. In fact, Mrs. Thatcher could not accept what she considered as an “idle society.” When she was very little, Mrs. Thatcher learned that working hard was not only a duty but also an enjoyment. These feelings emanated from the values that she dearly cherished such as independence and perseverance. In this sense, therefore, change only meant the questioning of the postwar consensus. The policies implemented during the consensus period aimed at helping Britain and her citizens reconstruct. Margaret Thatcher was determined to dismantle the Keynesian social democracy that had permeated British politics since World War Two because of changing circumstances. The novelty of her politics lay in getting rid of the postwar consensus, broadly based on the welfare state and government intervention and encouraging a society whose members should be self-reliant and independent in addition to a strong economy capable of self-regulating without the need for regulation from the government. Freedom, individualism and autonomy were the ultimate consequences of deregulation. These values were the original values of Conservatism and their implementation in the 1980s was nothing but a return to Old Tory Conservatism. The continuity of the Conservative Party, which was interrupted by the politics of Keynesianism of the Labour Party, had therefore been reestablished. In order to trace this continuity, a number of archival material have been studied in the Churchill Archives Centre in Cambridge; archival material such as the minutes of the Conservative Party or the discussions that took place among Conservatives. Besides, how members of the Conservative Party themselves define British Conservatism sheds light on the nature of Conservatism. The Conservative Party has been considered to be the monolithic party par excellence but as a result of the increasing influence of other parties, notably the Labour Party after World War Two, Conservatives became more aware of the need to think more, innovate, create thinks tanks and express their distinct opinions more widely. They were no longer afraid of change given that “Everything needs to change, so that everything can stay the same” (The Leopard by Giuseppe Tomasi di Lampedusa). An important part of this thesis deals with the economy. The variable of economic policy is perhaps the most visible criterion of success namely because it is easily quantifiable. It also reveals that economy has always been a priority among Conservatives. For Margaret Thatcher for instance, the Keynesianism of the postwar era had failed and should be abandoned. According to Thatcher, inflation was the problem to solve, not unemployment. The dichotomy between continuity and change will be analyzed not only in the public speeches of Margaret Thatcher but also the internal discussions of Conservatives. This plethora of definitions and opinions also concerns the legacy of the Iron Lady mainly through her successor, John Major, in addition to contemporary events such as the Brexit.
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Das humane Y-Box-Protein YB-1 und seine Bedeutung für die Prognose und den Therapieerfolg bei MammakarzinomSchmidt, Anja 12 December 2003 (has links)
Einer der Gründe für das Scheitern derzeitiger Behandlungsmethoden beim Brustkrebs ist die Resistenz gegenüber der angewandten Chemotherapie. Eine große Rolle bei der Entstehung der Multiplen Medikamentenresistenz spielt das MDR1-Gen und sein Genprodukt, das P-Glykoprotein. Das Y-Box-Protein YB-1 reguliert die Expression des MDR1-Gens; eine Überexpression und nukleäre Lokalisation von YB-1 geht im Brustkrebs mit einer gesteigerten P-Glykoprotein Expression einher. In dieser Arbeit wurden Gewebeproben von 83 Brustkrebspatientinnen auf eine YB-1 Überexpression im Tumor und im peritumoralen Epithel untersucht. YB-1 wurde mittels der immunhistochemischen APAAP-Methode an Formalin-fixierten, in Paraffin eingebetteten Brustkrebsgewebeproben nachgewiesen. Die klinische Relevanz der YB-1 Expression wurde untersucht, indem sie mit dem klinischen Verlauf in einem mittleren Beobachtungszeitraum von 61 Monaten und etablierten biologischen Tumorfaktoren wie Lymphknotenstatus, histologisches Grading, Tumorgröße, Hormonrezeptorstatus, uPA und PAI-1 verglichen wurde. In der Kohorte der Patientinnen mit einer postoperativen adjuvanten Chemotherapie zeigte sich eine 5-Jahres-Rezidivrate von 68 % bei einer hohen YB-1 Expression im Tumor und eine Rückfallrate von 39 % bei einer niedrigen YB-1 Expression. Unter Beachtung auch der YB-1 Expression im peritumoralen Epithel konnte ein noch größerer Unterschied hinsichtlich der 5-Jahres-Rezidivrate festgestellt werden. Diese betrug bei Patientinnen mit einer hohen YB-1 Expression 66 %, während bei Patientinnen mit einer niedrigen YB-1 Expression im Nachbeobachtungszeitraum kein Rezidiv festgestellt wurde. Bei der Gegenüberstellung der 5-Jahres-Rezidivraten in der Kohorte der Patientinnen ohne Zytostatikatherapie zeigte sich eine Rückfallrate von 30 % bei einer hohen YB-1 Expression und eine Rückfallrate von 0 % bei einer niedrigen YB-1 Expression. Eine hohe YB-1 Expression war demnach in beiden Kohorten mit einer schlechteren klinischen Prognose assoziiert. Das Ergebnis in der Gruppe der Patientinnen ohne postoperative Chemotherapie zeigt, dass YB-1 mit der Tumoraggressivität beim Brustkrebs korreliert. Eine Korrelation zwischen der YB-1 Expression und den etablierten prognostischen Faktoren Lymphknotenstatus, Tumorgröße und histologisches Grading konnte nicht festgestellt werden. Es wurde jedoch eine signifikante negative Korrelation zwischen der YB-1 Expression und dem Hormonrezeptorstatus und eine positive Korrelation zwischen YB-1 und den Faktoren uPA und PAI-1 gefunden. In dieser Arbeit wurde gezeigt, dass YB-1 eine klinische Relevanz besitzt mit Hinblick sowohl auf eine prognostische als auch eine prädiktive Bedeutung bei der Identifikation von Hoch-Risiko-Patientinnen im Brustkrebs in Ab- und Anwesenheit einer postoperativen Chemotherapie. / Intrinsic or acquired resistance to chemotherapy is one of the reasons for failure of current treatment regimens in breast cancer patients. P-glycoprotein and its gene mdr1 plays a major role in the development of a multi-drug resistant tumor phenotype. The Y-box protein YB-1 regulates the expression of mdr1. In human breast cancer, overexpression and nuclear localization is associated with upregulation of P-glycoprotein. In this study, tissues of 83 breast cancer patients have been analyzed with regard to YB-1 overexpression in tumor tissue and in surrounding benign breast epithelial cells. YB-1 has been detached by the immunohistochemical APAAP-method using formalin-fixed, paraffin-embedded breast cancer tissues. Clinical relevance of YB-1 expression was analyzed by comparing it with clinical outcome after a median follow-up of 61 months and with tumor biological factors lymph-node status, tumor size, histological grading, hormone-receptor status and the factors uPA and PAI-1. In patients who received postoperative chemotherapy, the 5-year-relapse rate was 68% in patients with high YB-1 expression in tumor cells and 39% in patients with low expression. With regard to YB-1 expression in surrounding benign breast epithelial cells, the 5-year-relapse rate was 66% in patients with high YB-1 expression whereas in patients with low expression no relapse has been observed so far. YB-1 thus indicates clinical drug resistance in breast cancer. In patients who received no chemotherapy, the 5-year-relapse rate was 30% in patients with high YB-1 expression whereas in patients with low YB-1 expression no relapse occurred. YB-1 thus correlates with breast cancer aggressiveness. In both groups high YB-1 expression was associated with poor clinical outcome. A correlation between YB-1 and tumor biological factors lymph-node status, tumor size and histological grading has not been found. But a significant negative correlation has been observed between YB-1 and hormone-receptor status and a positive correlation between YB-1 and uPA and PAI-1. This dissertation could show the clinical relevance of YB-1 with regard to a prognostic and predictive significance by identifying a high-risk group of breast cancer patients both in presence and absence of postoperative chemotherapy.
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Speziation von Gadolinium-MRT-Kontrastmitteln in UmweltmatrizesLindner, Uwe 26 July 2017 (has links)
Gd-Kontrastmittel werden in der Medizin für die Magnetresonanztomographie (MRT) benötigt, um einen besseren Bildkontrast zu erzielen. Nach der Anwendung gelangen diese Arzneimittel über das Abwasser in die Klärwerke und von dort in die jeweiligen anliegenden Oberflächengewässer. Somit wird es notwendig, den Verbleib der Gd-MRT-Kontrastmittel in der Umwelt zu verfolgen und aufzuklären. In dieser Arbeit werden für die Analyse von Umweltproben Methoden zur Speziesanalytik von Gd-Kontrastmitteln entwickelt und optimiert. Hierbei wird u.a. die Zwitterionische Hydrophile Interaktionschromatographie (HILIC) verwendet, die mit einer Induktiv- gekoppelten Plasma – Massenspektrometrie (ICP-MS) gekoppelt ist. / Gd based contrast agents are used for medical magnetic resonance imaging (MRI) to enhance the contrast of the image. After application and excretion, the drugs pass through the wastewater treatment plant (WWTP) and make their way into the surrounding surface water bodies. This makes it necessary to monitor the fate of the Gd based contrast agents in the environment. In this work, methods for speciation analysis of Gd based contrast agents in environmental samples were developed and optimised. For this purpose i.a. zwitterionic hydrophilic interaction chromatography (HILIC) is used, which is hyphenated with inductively coupled plasma mass spectrometry (ICP-MS).
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Deregulation von Zellzyklus und Apoptose beim Plattenepithelkarzinom des ÖsophagusGüner, Dilek 30 September 2003 (has links)
Störung des G1-Restriktionspunkts des Zellzyklus und Verlust der Wachstumskontrolle in Folge der Inaktivierung des Rb-Signalwegs ist ein häufiges Ereignis in malignen Tumoren. Gemeinsam mit der Hemmung von Apoptose-Signalwegen sind solche genetischen Ereignisse zentrale pathogenetische Faktoren der Tumorentstehung. Diese Veränderungen prägen aber auch entscheidend die Tumorbiologie und bestimmen somit intrinische und erworbene Therapieresistenz und konsequenterweise auch die klinische Prognose der Tumorerkrankung. In der vorliegenden Arbeit wurden Veränderungen im Rb- und im p53-Signalweg in Plattenepithelkarzinomen des Ösophagus untersucht. Diese retrospektive Studie wurde an Tumorproben von 53 mit kurativer Intention R0-resezierten Patienten durchgeführt. Proteinexpression wurde mittels Immunhistochemie und Mutationen mittels SSCP-PCR analysiert. Aktivierende Punktmutationen des K-ras Onkogens wurden mittels mutationsselektiver genomischer PCR und eines sequenzspezifischen Festphasen-Hybridisierungstests nachgewiesen. Die Analyse der individuellen Gene zeigte, dass Expressionsverlust der Rb-Signalwegskomponenten p16INK4a, p21CIP/WAF-1, p27KIP1 und von Rb selbst, sowie die Überexpression von Cyclin D1 bzw. Verlust des pro-apoptotischen Bcl-2 Homologs Bax mit schlechter Prognose, d.h. kürzerem Überleben korrelierte. Überexpression von Cyclin E, p53 oder Bcl-2, sowie Mutation von p53 bzw. K-ras zeigten hingegen keinen Einfluss auf die Prognose. Das längste Überleben wurde in einer Subgruppe von Patienten beobachtet deren Tumore eine Kombination günstiger Genotypen zeigte, und zwar niedrige Cyclin D1 Expression, sowie hohe Expression von Rb, p21CIP/WAF-1, p16INK4a und Bax. Diese Ergebnisse zeigen, dass eine Multigen- oder "Multimarker"-Analyse von Genen, die konsekutiv oder synergistisch in Zellzyklus- und Apoptose-Signalwegen agieren, zur Prognoseabschätzung der Analyse individueller Gene deutlich überlegen ist. Die Identifikation solcher genetischer Markerprofile sollte sich auch zukünftig als nützlich für die klinische Entscheidungsfindung in der Therapie maligner Tumore erweisen und wird konventionelle klinische und pathologische Faktoren komplementieren, die bisher keine ausreichende Prognoseabschätzung erlauben. / Malignant tumors frequently show inactivation of the Rb pathway and, as a result, deregulation of the G1 restriction point of the cell cycle and loss of growth control. Together with the inhibition of apoptosis signaling pathways, such events are key pathogenetic factors in tumor development. Moreover, these aberrations are decisive in determining tumor biology and characteristics such as intrinisic or acquired resistance to therapy and, consequently, the clinical prognosis of the malignant disease. In the present work, aberrations in the Rb and the p53 pathway were analysed. This retrospective study was undertaken in a cohort of 53 patients with esophageal squamous cell carcinoma who underwent R0 resection with a curative intent. Protein expression in tumor samples was analysed by means of immunohistochemistry and mutations were investigated by the use of genomic SSCP-PCR. Activating point mutations of the K-ras oncogene were detected by the use of mutation-selective genomic PCR and a sequence specific solid phase hybridization assay. The analysis of individual genes showed a correlation between poor prognosis, i.e. short overall survival, and loss of the Rb pathway components p16INK4a, p21CIP/WAF-1, p27KIP1, and Rb itself, or overexpression of cyclin D1 or loss of the pro-apoptotic Bcl-2 homolog Bax. In contrast, overexpression of cyclin E, p53 or Bcl-2 and mutation of p53 or K-ras had no influence on disease prognosis. The longest survival was found in a subgroup of patients whose tumors exhibited a combination of favorable genotypes, i.e. low expression of cyclin D1, and high expression of Rb, p21CIP/WAF-1, p16INK4a and Bax. These results demonstrate that a multigene or "multimarker"-analysis of genes that act consecutively or synergistically in cell cycle and apoptosis signaling pathways is far superior to determine disease prognosis when compared to the analysis of individual genes. The identification of such genetic marker profiles should proove beneficial in clinical decision making in the therapy of malignant tumors. In the future, such diagnostic tools may be useful to complement conventional clinical and pathologic factors which in most instances do not allow prediction of disease prognosis.
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Estudo da interação das células-tronco mesenquimais e linfócitos no modelo da doença do enxerto contra hospedeiro / Study of mesenchymal stem cells and lymphocytes interaction in graft versus host disease modelNormanton, Marília 10 July 2014 (has links)
Uma das principais complicações inerentes ao transplante de células-tronco hematopoiéticas é a doença do enxerto contra hospedeiro (DECH), que se trata da resposta imunológica contra os tecidos do receptor pelas células T do doador contidas no transplante. Este quadro é responsável por 15-30% das mortes que ocorrem após o transplante de células-tronco hematopoiéticas alogênicas. Apesar dos recentes avanços para reduzir a incidência de DECH através de alternância de regimes profiláticos reduzindo a intensidade do condicionamento, são poucos os tratamentos efetivos. Recentemente, o potencial imunomodulador das células-tronco mesenquimais tornou-se o foco de vários estudos. Alguns autores descreveram a atuação destas células na redução da resposta imunológica através da inibição da proliferação de células T, representando um novo potencial terapêutico para DECH. Mediante esse conhecimento, investigamos o papel das células-tronco mesenquimais na proliferação, apoptose e na produção de citocinas por linfócitos T. Nossos resultados mostraram que a presença de células-tronco mesenquimais nas culturas regulam negativamente a proliferação de linfócitos T estimulados de forma independente de contato e a apoptose de forma parcialmente dependente de contato. Observamos também que linfócitos T virgens em diferenciação para Th17 na presença de células-tronco mesenquimais apresentam redução na capacidade de produzir duas importantes citocinas efetoras implicadas na DECH, o interferon gama (IFN-y) e a interleucina 17A (IL-17A). Investigamos se a prostaglandina E2 (PGE2), por depletar triptofano, estava envolvida com a diminuição de proliferação de linfócitos T quando em cultivo com células-tronco mesenquimais. Utilizamos nas culturas a indometacina (IDT), um anti-inflamatório bloqueador de cicloxigenase (COX 1 e 2) e portanto da via da PGE2. Entretanto, observamos que o bloqueio da via da PGE2 inibia ainda mais a proliferação de linfócitos T e isto ocorria de acordo com a dose de IDT. Com o resultado deste experimento concluímos que, se a proliferação de linfócitos é inibida pela depleção de triptofano do meio, ela não ocorre via PGE2. Entretanto ainda não conseguimos esclarecer se esta via é ativada por outras moléculas, ou se é esta a via realmente responsável pela inibição da proliferação de linfócitos. No que concerne a via de inibição de apoptose, mostramos que a cadeia alpha do receptor de IL-7 (CD127) está aumentada na superfície de linfócitos T quando em presença de células-tronco mesenquimais. Verificamos que o bloqueio de IL-7 nas culturas aumenta a apoptose em linfócitos, bem como sua adição causa diminuição de apoptose. Identificamos a produção intracelular de IL-7 nas células-tronco mesenquimais, relacionando estas células e IL-7 com a inibição de apoptose em linfócitos T nestas condições. Este trabalho gerou dados que permitiram a compreensão de alguns possíveis mecanismos pelos quais as MSCs podem atuar sobre linfócitos T ativados e/ou alorreativos; mecanismos estes que podem ser utilizados como base para futuras investigações na elucidação e prevenção da DECH / A major complication after hematopoietic stem cell transplantation is the graft versus host disease (GVHD), which is an immunological response of transplanted donor T cells against the recipient tissues; this outline is responsible for 15-30% of deaths that can occur after allogeneic hematopoietic stem cells transplant. Despite recent advances in reducing GVHD incidence by alternating prophylactic regimens, thus reducing the intensity of conditioning, there are few effective treatments. Recently, the immune modulatory potential of mesenchymal stem cells has become the focus of several studies. Some authors described the role of these cells in reducing immune response by inhibiting T cell proliferation, representing a potential new therapy for GVHD. Through this knowledge, we investigated the mesenchymal stem cells role into T lymphocytes proliferation, apoptosis and cytokine production. Our results showed that the presence of mesenchymal stem cells into the cultures downregulates the proliferation of stimulated lymphocytes independent of contact and apoptosis of stimulated lymphocytes in partially contact-dependent manner. We also observed during naive T lymphocytes differentiation into Th17 cells, that the mesenchymal stem cell presence reduces the lymphocyte ability in producing the GVHD major effectors cytokines, interferon gamma (IFN-y) and interleukin-17A (IL-17A). We investigated whether prostaglandin E2 (PGE2) was involved in the reduction of T lymphocytes proliferation, when cultured with mesenchymal stem cells, by tryptophan depletion. Indomethacin (IDT), an anti-inflammatory drug blocker of cyclooxygenase (COX 1 and 2) and therefore PGE2 pathway, was used. However, we observed that, according to IDT dose, blocking this pathway further inhibited lymphocyte proliferation. With this result we conclude that if lymphocyte proliferation is inhibited by tryptophan depletion, it does not occur via PGE2. However, we still cannot say whether this pathway is activated by other molecules, or if this pathway is actually responsible for T lymphocytes proliferation inhibition. Regarding the apoptosis inhibition in T lymphocytes, we show that the IL-7 receptor alpha chain (CD127) is increased on the surface of T lymphocytes when in the presence of mesenchymal stem cells. We found that IL-7 blockage in the cultures increases apoptosis in T lymphocytes, as well as their addition causes apoptosis decrease. We also identified the intracellular production of IL-7 on mesenchymal stem cells, linking these cells and IL-7 directly with apoptosis inhibition in T lymphocytes under these conditions This work has generated data that allowed the understanding of some possible mechanisms by which MSCs can act on activated and/or alloreactive T lymphocytes; mechanisms that can be used as a basis for future research in the elucidation and prevention of GVHD
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A representação da imprensa sobre o desastre com os aviões Legacy e Boeing: uma visão crítica sob a perspectiva da gramática sistêmico-funcionalVieira, Wander Marques 13 April 2015 (has links)
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Previous issue date: 2015-04-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research analyzes the Newspaper Report genre in reference to the
Representation processes of an event - the air crash which involved a Legacy, an
executive jet belonging to an American charter company, and a Boeing, from a
Brazilian airline, on September 29, 2006 - investigating the existing relations between
some lexical-grammatical choices and the underlying ideology and power involved.
Two reports published in leading Brazilian and American newspapers are analyzed
for the Legitimacy which characterizes the Argumentation found in the reports. The
analysis is based on the distinction called Writer s Consciousness of the Audience ,
between the Interactive and Interactional components involved in the interpersonal
function. According to the Interactive components, this research aims to analyze not
only the Report genre structure - its stages and finalities - based on proposals on the
structure of Argumentation, but also the Textual Modes which build it. As for the
Interactional components, which comprise Appraisal and Modality, this research
wants to examine the Intertextual and Intersubjective relations prompted by the
Voices and the Alignment existing in the text. Methodologically, these resources are
examined in the light of the Critic Linguistics with the support of Systemic-Functional
Grammar to show that the interpretations given by the two newspapers are
constructed by specific choices on the microlevel of clauses reflecting the attribution
of specific ideology from interior or exterior members of a group on the underlying
macrolevel. In so being, this research seeks to answer the following questions: a)
How the Legacy-Boeing air crash is represented by either newspapers? b) What role
do the Interactive and Interactional components exert on the Representation? c)
What is the contribution of Systemic-Functional Grammar to the research conducted / Esta pesquisa examina o gênero Reportagem de Jornal no que se refere aos
processos de Representação de um evento - o acidente aéreo, ocorrido em
29/09/06, envolvendo um Legacy, jato executivo da ExcelAire, uma empresa
americana, e um Boeing, da Gol Linhas Aéreas Inteligentes, uma empresa brasileira
- investigando as relações entre certas escolhas léxico-gramaticais e as relações de
ideologia e poder a elas subjacentes. No exame da persuasão que ocorre em duas
reportagens: uma publicada em jornal brasileiro e outra, em jornal americano,
examino a noção de Legitimidade, que caracteriza a Argumentação desenvolvida
nas reportagens. A análise apoia-se na distinção feita pela chamada Consciência
da Audiência por parte do Escritor , entre os componentes Interativo e Interacional,
envolvidos na função interpessoal. Com referência ao componente Interativo,
examino não só a estrutura do gênero Reportagem de Jornal - seus estágios e
finalidades - com base em propostas sobre a estrutura da Argumentação, mas
também os Modos Textuais que o constroem. Quanto ao componente Interacional,
que envolve a Avaliatividade explícita e implícita e a Modalidade, examino as
relações de Intertextualidade e de Intersubjetividade, promovidas pelas Vozes e o
Alinhamento que percorrem o texto. Metodologicamente, esses recursos serão
examinados à luz da Linguística Crítica, com o apoio da Gramática Sistêmico-
Funcional, para mostrar que as interpretações dadas pelos dois jornais são
construídas por escolhas específicas no micronível das orações, refletindo a
atribuição de ideologia específica a membros interiores ou exteriores ao grupo , no
macronível subjacente. Para tanto, a análise deve responder às seguintes
perguntas: (a) Como o acidente envolvendo o Legacy e o Boeing é representado por
cada um dos jornais? (b) Que papel exercem os componentes Interativo e
Interacional nessa Representação? (c) Qual é a contribuição da Gramática
Sistêmico-Funcional para o exame feito em (a) e (b)? Os resultados mostram que,
ainda que o gênero Reportagem de Jornal procure primar-se pela imparcialidade, a
língua, sendo um meio de refração e estruturação de significados, além de se
considerar que as instituições jornalísticas situam-se social, econômica e
politicamente, fica patente que o elemento ideológico entra em jogo, e a
imparcialidade dá lugar à parcialidade expressa por meio das estratégias retóricas
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