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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.
11

A correspondência, as memórias e as notas de Carlos Fradique Mendes - uma imagem de cosmopolita para o Portugal do século XIX? / Letters, memories and notes of Carlos Fradique Mendes a cosmopolitan image for the nineteenth century Portugal?

Prado, Thais Marassi 27 September 2011 (has links)
A presente tese de Doutorado pretende analisar a produção literária atribuída ao personagem Carlos Fradique Mendes em A Correspondência de Fradique Mendes de Eça de Queirós, suas correspondências e a primeira parte da obra intitulada Memórias e Notas. Trata-se da abordagem das diversas estratégias narrativas, discursivas e composicionais que formam o legado fradiquiano, buscando a resposta para a dúvida que originou a presente pesquisa: Fradique pode ser considerado o protótipo de homem cosmopolita do século XIX português? / This doctoral thesis aims to analyze literary production attributed to the character Carlos Fradique Mendes in As Correspondências de Fradique Mendes of Eça de Queirós , his letters and the first part of the work entitled \"Memórias e Notas.\" This is the approach of the various narrative strategies, discursive and compositional fradiquiano that form the legacy, seeking the answer to the question that originated this research: Fradique can be considered the prototype of the nineteenth century cosmopolitan Portuguese?
12

A correspondência, as memórias e as notas de Carlos Fradique Mendes - uma imagem de cosmopolita para o Portugal do século XIX? / Letters, memories and notes of Carlos Fradique Mendes a cosmopolitan image for the nineteenth century Portugal?

Thais Marassi Prado 27 September 2011 (has links)
A presente tese de Doutorado pretende analisar a produção literária atribuída ao personagem Carlos Fradique Mendes em A Correspondência de Fradique Mendes de Eça de Queirós, suas correspondências e a primeira parte da obra intitulada Memórias e Notas. Trata-se da abordagem das diversas estratégias narrativas, discursivas e composicionais que formam o legado fradiquiano, buscando a resposta para a dúvida que originou a presente pesquisa: Fradique pode ser considerado o protótipo de homem cosmopolita do século XIX português? / This doctoral thesis aims to analyze literary production attributed to the character Carlos Fradique Mendes in As Correspondências de Fradique Mendes of Eça de Queirós , his letters and the first part of the work entitled \"Memórias e Notas.\" This is the approach of the various narrative strategies, discursive and compositional fradiquiano that form the legacy, seeking the answer to the question that originated this research: Fradique can be considered the prototype of the nineteenth century cosmopolitan Portuguese?
13

En undersökning om hur Robotsystem 70 skytten presterar i kyla

Karlsson, Andreas January 2009 (has links)
<p>I denna uppsats har det studerats hur kyla påverkar Robot 70 skyttens prestanda. För att göra detta har en hypotesprövande metod använts. Hypotesen lyder: ”En robotskytts finmotorik påverkas av kyla så till den grad att träff inte är sannolik.”</p><p>Hypotesen används till hjälp att svara på följande frågeställningar:</p><p>Frågeställning 1:</p><p>I vilken utsträckning påverkas robot 70-skyttens finriktningsförmåga av kyla?</p><p>Frågeställning 2:</p><p>Hur kan luftvärnsregementet förbättra nyttjandet av Robot 70 gruppens utrustning för att minska kylans påverkan på robotskyttens prestanda?</p><p>Ett experiment har använts för att verifiera eller falsifiera hypotesen. Sju personer från Luftvärnsregementet har skjutit simulerade avfyringar inom- och utomhus, vid olika temperaturer. Resultatet från robotarna avfyrade inomhus vid 20°C hade en ungefärlig träffsannolikhet för direktträff på 94 %. Avfyringarna i segmentet med lägst uppmätta tumtemperaturer hade enligt mina mätningar en betydligt lägre träffsannolikhet för direktträff.</p><p>Vad som verkar sänka temperaturen robotskyttens tumme mest, är värmeledning från robotsystemets styrspak. Slutsatsen är att detta verkar beror på att styrspaken är tillverkad av aluminium. Genom att isolera styrspaken kan det undvikas att skyttens tumme kyls ned och därmed minskar dennes träffsannolikhet.</p> / <p>In this essay it has been studied how cold environment can affect the gunner of the RBS 70.</p><p>In this study, the method of testing a hypothesis has been used. Hypothesis: “The Gunner is affected by cold to such an extent that a hit is not probable”</p><p>The hypothesis is used in helping to answer the following two questions:</p><p><strong>1.      </strong>To what level is the RBS 70 Gunner affected by cold?</p><p><strong>2.      </strong>How can the Swedish AD Regiment improve its use of equipment in order to   reduce the effects of cold weather, on the RBS 70 gunners’ ability to aim?</p><p> A test was performed to verify or falsify the hypothesis. Seven people from the Swedish AD Regiment fired simulated missiles both indoors and outdoors, in different temperatures. The results show that the missiles fired indoors at 20°C had an approximated direct hit-ratio of 94 percent. The firings where the thumb temperatures were the lowest had a lot lower direct hit ratio.</p><p>The greatest issue lowering the gunners thumb temperature was the temperature of the joystick of the sight. The conclusions are that the joystick, which is made of aluminium, must be isolated to avoid cooling the gunners’ thumb. Otherwise it will be harder to hit the target at a low temperature.</p>
14

En undersökning om hur Robotsystem 70 skytten presterar i kyla

Karlsson, Andreas January 2009 (has links)
I denna uppsats har det studerats hur kyla påverkar Robot 70 skyttens prestanda. För att göra detta har en hypotesprövande metod använts. Hypotesen lyder: ”En robotskytts finmotorik påverkas av kyla så till den grad att träff inte är sannolik.” Hypotesen används till hjälp att svara på följande frågeställningar: Frågeställning 1: I vilken utsträckning påverkas robot 70-skyttens finriktningsförmåga av kyla? Frågeställning 2: Hur kan luftvärnsregementet förbättra nyttjandet av Robot 70 gruppens utrustning för att minska kylans påverkan på robotskyttens prestanda? Ett experiment har använts för att verifiera eller falsifiera hypotesen. Sju personer från Luftvärnsregementet har skjutit simulerade avfyringar inom- och utomhus, vid olika temperaturer. Resultatet från robotarna avfyrade inomhus vid 20°C hade en ungefärlig träffsannolikhet för direktträff på 94 %. Avfyringarna i segmentet med lägst uppmätta tumtemperaturer hade enligt mina mätningar en betydligt lägre träffsannolikhet för direktträff. Vad som verkar sänka temperaturen robotskyttens tumme mest, är värmeledning från robotsystemets styrspak. Slutsatsen är att detta verkar beror på att styrspaken är tillverkad av aluminium. Genom att isolera styrspaken kan det undvikas att skyttens tumme kyls ned och därmed minskar dennes träffsannolikhet. / In this essay it has been studied how cold environment can affect the gunner of the RBS 70. In this study, the method of testing a hypothesis has been used. Hypothesis: “The Gunner is affected by cold to such an extent that a hit is not probable” The hypothesis is used in helping to answer the following two questions: 1.      To what level is the RBS 70 Gunner affected by cold? 2.      How can the Swedish AD Regiment improve its use of equipment in order to   reduce the effects of cold weather, on the RBS 70 gunners’ ability to aim?  A test was performed to verify or falsify the hypothesis. Seven people from the Swedish AD Regiment fired simulated missiles both indoors and outdoors, in different temperatures. The results show that the missiles fired indoors at 20°C had an approximated direct hit-ratio of 94 percent. The firings where the thumb temperatures were the lowest had a lot lower direct hit ratio. The greatest issue lowering the gunners thumb temperature was the temperature of the joystick of the sight. The conclusions are that the joystick, which is made of aluminium, must be isolated to avoid cooling the gunners’ thumb. Otherwise it will be harder to hit the target at a low temperature.
15

Η επίπτωση εκτεταμένης πειραματικής ηπατεκτομής καθώς και του χειρισμού Pringle, στη μορφολογία του εντερικού βλεννογόνου, την εντερική βακτηριακή μετακίνηση και ενδοτοξιναιμία Φαρμακολογικοί χειρισμοί για την πρόληψη και αποφυγή του φαινομένου

Κιρκιλέσης, Ιωάννης Γ. 17 December 2008 (has links)
Σκοπός της μελέτης ήταν να εξετάσουμε, σε ένα πειραματικό μοντέλο πειραματικής ηπατεκτομής (70%) αφ’ ενός και παροδικής απόφραξης του ηπατοδωδεκαδακτυλικού συνδέσμου (χειρισμός Pringle) αφ’ ετέρου, το φαινόμενο της βακτηριακής μετακίνησης, της ενδοτοξιναιμίας, καθώς και τις μεταβολές οι οποίες συμβαίνουν στην εντερική χλωρίδα και τον εντερικό βλεννογόνο. Σε αυτά τα δύο μοντέλα προσπαθήσαμε κατ’ αρχήν να πιστοποιήσουμε την αυξημένη μετακίνηση των εντερικών βακτηρίων στους μεσεντέριους λεμφαδένες και την διαπίδυση ενδοτοξινών από τον αυλό του εντέρου στην πυλαία και την αορτή. Στα ίδια μοντέλα προσπαθήσαμε να αναστείλουμε τα ανωτέρω φαινόμενα με φαρμακολογικούς χειρισμούς, μελετώντας πρώτον τη χορήγηση λακτουλόζης από το στόμα, η οποία έχει την ικανότητα να δεσμεύει την ενδοτοξίνη και να σχηματίζει σύμπλεγμα που δεν απορροφάται από το έντερο, με σκοπό τη μείωση της ενδοαυλικής απορροφήσιμης ενδοτοξίνης και δεύτερον τη χορήγηση δυσαπορρόφητων αντιβιοτικών από το στόμα, με σκοπό την ποσοτική ελάττωση του πληθυσμού της μικροβιακής χλωρίδας στον αυλό του εντέρου. Τα αποτελέσματα κάθε φάσης της μελέτης της ηπατεκτομής (70%) και του χειρισμού Pringle είχαν ως εξής: Η ηπατεκτομή (70%), προάγει την εντερική βακτηριακή μετακίνηση στους μεσεντέριους λεμφαδένες και στο ήπαρ, αυξάνει την ενδοτοξιναιμία και επιφέρει ιστολογικές αλλαγές στο ύψος των λάχνων. Η χορήγηση λακτουλόζης δημιουργεί τις κατάλληλες συνθήκες που επιφέρουν την μείωση των θετικών καλλιεργειών ιδιαίτερα αυτών του ήπατος και ελαττώνει την ενδοτοξίνη στην πυλαία. Η αποστείρωση του εντέρου με τη χορήγηση δυσαπορρόφητων αντιβιοτικών, μειώνει την εντερική βακτηριακή μετακίνηση στους μεσεντέριους λεμφαδένες και την ενδοτοξιναιμία. Ο χειρισμός Pringle, προάγει την εντερική βακτηριακή μετακίνηση και την ενδοτοξιναιμία, ενώ η απόπτωση ελαττώνεται με την αποστείρωση του εντέρου και τη χορήγηση λακτουλόζης μόνο άμεσα μετά τον χειρισμό. Η εξασφάλιση της ανατομικής και λειτουργικής ακεραιότητας του εντερικού βλεννογόνου έχει ιδιαίτερη σημασία στη διατήρηση του βλεννογόνιου εντερικού φραγμού και αποτρέπει την ενδοτοξιναιμία και τη βακτηριακή μετακίνηση. Η αποκατάσταση της δομικής και λειτουργικής ακεραιότητας του εντερικού βλεννογόνου, στην εκτεταμένη ηπατεκτομή, με τη χορήγηση μη απορροφήσιμων αντιβιοτικών και λακτουλόζης, αναστέλλει σημαντικά τα ανωτέρω φαινόμενα. / The purpose of this study is to investigate on an experimental model of extended hepatectomy(70%) and temporary occlusion of the hepatoduodenal ligament (Pringle maneuver), the phenomenon of bacterial translocation, endotoxaemia as well as the changes that are taking place, both in the intestinal flora and intestinal mucosa. In both models we attempt to demonstrate the increase translocation of intestinal bacteria to mesenteric lymph nodes (MLNs) and increase of endotoxin in the systemic and portal circulation. Using the same models, we attempted to inhibit the above phenomena with pharmacological manipulation. We examined the decrease of the endotoxins translocation, by administering per.os lactulose, which has the property to bind the endotoxin formatting a nonabsorbable comlex in the gut lumen. We also investigated the effect of nonabsorbable antibiotics per. os on reducing the intestinal flora. Our results indicated that, extended hepatectomy (70%) increased translocation of intestinal bacteria to mesenteric lymph nodes and liver and increased the endotoxaemia inducing the decrease of intestinal villus height. The administering of lactulose created the proper conditions which decreased positive liver cultures and reduced the endotoxin concentrations in portal blood. Gut decontamination by administration of nonabsorbable antibiotics reduced the intestinal flora, the intestinal bacteria translocation to MLNs and endotoxaemia. Pringle maneuver promoted the intestinal bacterial translocation and endotoxaemia. Apoptosis decreases, by gut decontamination and administration of lactulose only immediately after Pringle maneuver. The anatomic and functional integrity reassurance, of intestinal mucosa, has strong significance for the preservation of intestinal mucosal barrier to prevent endotoxaemia and bacterial translocation. The structural and functional establishment of enteric mucosa integrity, after extended hepatectomy, by administration of nonabsorbable antibiotics and lactulose, inhibit considerably the above phenomena.
16

Decoração soteropolitana na década de 70: cores, formas e representações

Pessôa, Yumara Souza January 2007 (has links)
252f. / Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-04-05T12:28:29Z No. of bitstreams: 3 Pessôaparte3seg.pdf: 14917280 bytes, checksum: c7ce2e7f6dd8bcb073bbf9ae2ac7402e (MD5) Pessôaparte2seg.pdf: 14135034 bytes, checksum: d8a3377692ed70c85ea28d6ae0943b45 (MD5) Pessôaparte1seg.pdf: 4894630 bytes, checksum: b9de2025cf797ce06c9dfc04b56467e6 (MD5) / Approved for entry into archive by Lêda Costa(lmrcosta@ufba.br) on 2013-04-18T12:34:39Z (GMT) No. of bitstreams: 3 Pessôaparte3seg.pdf: 14917280 bytes, checksum: c7ce2e7f6dd8bcb073bbf9ae2ac7402e (MD5) Pessôaparte2seg.pdf: 14135034 bytes, checksum: d8a3377692ed70c85ea28d6ae0943b45 (MD5) Pessôaparte1seg.pdf: 4894630 bytes, checksum: b9de2025cf797ce06c9dfc04b56467e6 (MD5) / Made available in DSpace on 2013-04-18T12:34:39Z (GMT). No. of bitstreams: 3 Pessôaparte3seg.pdf: 14917280 bytes, checksum: c7ce2e7f6dd8bcb073bbf9ae2ac7402e (MD5) Pessôaparte2seg.pdf: 14135034 bytes, checksum: d8a3377692ed70c85ea28d6ae0943b45 (MD5) Pessôaparte1seg.pdf: 4894630 bytes, checksum: b9de2025cf797ce06c9dfc04b56467e6 (MD5) Previous issue date: 2007 / A pesquisa versa sobre a Decoração Residencial das classes média e alta na cidade de Salvador, na década de 70 do século XX, analisada nos seus aspectos materiais e simbólicos. O trabalho objetiva contribuir para o resgate da História da Decoração soteropolitana, e justifica - se pela inexistência de produção acadêmica suficiente nessa área, distinta da História do Mobiliário, tanto nacionalmente, quanto na Bahia. As informações obtidas em livros e periódicos, fotografias familiares e em entrevistas com profissionais atuantes na área e membros das classes sociais privilegiadas no período de estudo, subsidiaram o desenvolvimento do trabalho que estruturou - se em quatro capítulos.A partir da análise de questões relacionadas ao exercício profissional nas áreas de arquitetura, arte e design, estabeleceu - se o conceito de Decoração que norteou a Dissertação e que tomou forma plástica em três ambientações, reunidas sob a denominação de Tribos 70: lembrança e esquecimento.A definição da Decoração como manifestação cultural, implicou no levantamento do contexto histórico do Brasil e de Salvador na década de 70, notadamente no que se refere aos aspectos de modernização da cidade e seu rebatimento nas formas de morar e de decorar.Através da análise da proposições(“tendências”) das revistas especializadas, nacionais e estrangeiras, na sua relação com o mercado local de móveis e com as decorações das residências, é possível observar não só a pluralidade de estilos adotados em Salvador entre 1970 e 1979, como também, a existência do binômio,modernidade - tradição, reforçado pelo passado colonial da cidade. Assim, através desse estudo, podemos exemplificar a relação entre os valores sócio -culturais (representações) e a configuração (cores e formas) dos interiores residenciais. / Rio de Janeiro
17

Perfil ClÃnico e Laboratorial dos Pacientes com Leucemia Linfoide CrÃnica Atendidos no ServiÃo de Hematologia e Hemoterapiado HUWC-HEMOCE / Clinical and Laboratorial Profile of Patients with Chronic Lymphocytic Leukemia admitted at the hematology and hemotherapy service of the University Hospital Walter CantÃdio (HUWC) and Hemotherapy and Hematology Center of Cearà (HEMOCE).

Richeyla Kelly de Assis CustÃdio 03 September 2009 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / A leucemia linfocÃtica crÃnica (LLC) à a leucemia mais freqÃente nos paÃses ocidentais, ocorrendo em cerca de 30% de todas as leucemias do adulto, acometendo principalmente a populaÃÃo acima de 65 anos de idade. à caracterizada pela proliferaÃÃo clonal de linfÃcitos tipo B CD5 positivos. Do ponto de vista epidemiolÃgico, raramente à vista entre os orientais e a sua incidÃncia nÃo sofre influÃncia de agentes ambientais como substÃncias tÃxicas ou radiaÃÃes ionizantes. Os pacientes com LLC podem apresentar evoluÃÃo clÃnica variÃvel desde indolente a forma mais agressiva e rapidamente fatal. Na Ãltima dÃcada, houve um grande avanÃo no conhecimento da fisiopatologia desta doenÃa e fatores de prognÃstico de maior impacto foram estabelecidos e, do ponto de vista terapÃutico, novos medicamentos com maior eficÃcia surgiram. Desta forma à interessante conhecer a real situaÃÃo desta doenÃa com caracterÃsticas epidemiolÃgicas, clÃnicas e de prognÃstico muito peculiares. Nesse trabalho traÃamos o perfil (demogrÃfico, clÃnico e laboratorial) dos pacientes com LLC atendidos no serviÃo de Hematologia e Hemoterapia do Cearà (HEMOCE) do HUWC, correlacionando a expressÃo dos marcadores de prognÃstico (CD38 e ZAP-70) com algumas variÃveis e com o tratamento farmacolÃgico. Foram utilizadas amostras de sangue de 55 pacientes com LLC confirmados atravÃs de imunofenotipagem, em tratamento ou nÃo. Os marcadores CD38 e ZAP-70 foram analisados por citometria de fluxo e a dosagem de &#946;2-microglobulina obtida atravÃs de mÃtodo imunoenzimÃtico (ELISA). Os dados obtidos foram analisados atravÃs de programa estatÃstico. Observamos um leve predomÃnio de pacientes do sexo masculino (1,4:1), 78% acima de 65 anos de idade e 60% eram procedentes da capital. Quanto ao estadiamento, 50,9% pacientes foram classificados como de baixo risco, segundo classificaÃÃo de Rai. Quanto a evoluÃÃo clÃnica, mais de 30% dos pacientes nÃo apresentavam sinais clÃnicos, nem no momento do diagnÃstico nem no final do estudo. Em relaÃÃo aos marcadores, 22,2% dos pacientes apresentavam expressÃo do ZAP-70 e 24,13% do CD38. NÃo houve diferenÃa estatÃsticamente significante entre os marcadores ZAP-70 e CD38 e as variÃveis hematolÃgicas (Hb, Ht e Plaquetas). Houve correlaÃÃo entre o estadiamento clÃnico de Rai e o tratamento farmacolÃgico e com os marcadores de prognÃstico (ZAP-70 e CD38). O perfil foi caracterizado por pacientes em estÃgios clÃnicos, segundo Rai, de baixo risco, com ausÃncia da expressÃo dos marcadores de prognÃstico (ZAP-70 e CD38) e com ausÃncia de tratamento especÃfico. / Chronic Lymphocytic Leukemia (CLL) is the most frequent leukemia on western countries, responding for 30% off all leukemia cases, reaching, specially, the under 65 years old population. It is characterized by accumulation of neoplasic mature B lymphocytes positives CD5. Concerning epidemiology, it is barely seen among eastern people, and its incidence is not influenced by environmental agents, such as toxic substances or ionizing radiation. CLL-B patients may present a variable clinical evolution, which goes from indolent to aggressive and rapidly fast cases. On last decade, there have been great advance on biology knowledge of this disease, and greater impact prognostic factors have been established. In relation to treatment, new medication, with better efficacy, appeared. Therefore, it is interesting to know the real situation of this disease, which has singular epidemiological, clinical and prognostic characteristics. In this work we trace the demographical, clinical and laboratorial profile of patients with CLL-B, at a state hemocenter (HEMOCE). We correlate prognostic markers expression (CD38 e ZAP-70) with some variable and with pharmacological treatment. We used 55 blood samples from patients CLL-B confirmed by their immunophenotypes; these patients may or may not be in treatment. CD38 and ZAP-70 were analyzed by flow cytometry and &#946;2-microglobulin dosage, obtained through ELISA. Results were treated by statistic program. We see a discrete prevalence of male patients (1,4:1), 78% are under 65 years old and 60% live at CearÃâs capital. In relation to Rai staging system, 50,9% were classified as low risk patients. Concerning clinical evolution, more than 30% of the patients did not show clinical signs, neither at diagnose moment nor at the end of this study. In relation to the markers, 22,2% of the patients show ZAP-70 expression, and 24,13% show CD38 expression. There was no significant statistic difference between ZAP-70 and CD38 markers and hematological variable (Hb, Ht and platelets). There was correlation between Raiâs staging and pharmacological treatment and with prognostic markers. CONCLUSION: The profile was characterized by low risk patients, according Raiâs staging, it lacks prognostic markers expression and it also lacks specific treatment.
18

Rôle de la sous-unité sigma de l'ARN polymérase bactérienne dans la tolérance aux antibiotiques / Role of the RNAP sigma subunit in tolerance to antibiotics

Benabad, Zakia 17 November 2016 (has links)
L’ARN polymérase (ARNP) est l'enzyme centrale d'expression des gènes. Toutes les formes de vie possèdent de l’ARNP. C’est un complexe protéique formé de plusieurs sous-unités responsables du processus de transcription qui aboutit à la synthèse de l’ARN à partir d’une matrice ADN. Les procaryotes possèdent un seul type d’ARNP responsable de la synthèse de tous les ARNs de la cellule, alors que les eucaryotes possèdent trois types d’ARNPs pour la synthèse des différents types d’ARNs.L’ARNP est la cible d’un grand nombre de protéines et de petites molécules de régulation dont certains antibiotiques utilisés en première ligne pour le traitement de diverses maladies infectieuses. La sous-unité sigma de l’ARN polymérase bactérienne est impliquée dans toutes les étapes de l'initiation de la transcription qui est le point crucial de l'expression des gènes. Les sous-unités sigma activent par exemple les gènes de virulence des bactéries pathogènes et sont impliquées dans la persistance qui est une forme de survie aux traitements antibiotiques.Ce projet a permis de déterminer le rôle de la sous-unité sigma de l'ARN polymérase bactérienne dans la résistance à la lipiarmycine (Fidaxomicin). Nous avons utilisé des approches biochimiques, biophysiques et génétiques pour l’étude de la dynamique des interactions ADN-protéine dans les complexes formés par l’ARN polymérase, l’antibiotique et de l’ADN des promoteurs.Les résultats de cette étude montrent que la sensibilité de l’ARNP dépend fortement de la structure de la région 3.2 de sigma et que les régions 1.2 et 3.2 de la sous-unité sigma sont impliquées dans la formation du complexe d’initiation de la transcription. Les mutations au niveau de ces régions affectent allostériquement l'action de la lipiarmycine en compromettant la formation du complexe ouvert. Ces résultats suggèrent que la conformation et la mobilité de la région 3.2 dépendent fortement de sa séquence. Ces travaux contribueront de manière significative à la compréhension des bases moléculaires de la résistance aux antibiotiques; Les approches méthodologiques développées pendant ce projet pourront être étendues à l'analyse d’autres antibiotiques ciblant l’ARNP bactérienne et à l’analyse des autres facteurs de transcription. / The RNA polymerase (RNAP) is the central enzyme for genes expression. All forms of life own RNAP. It is a multi-protein complex composed of several subunits responsible of the process of the transcription. The prokaryotes have only one type of RNAP responsible of synthesis of all RNAs in the cells, whereas eukaryotes have three types of RNAPs for the synthesis of the various types of RNAs.RNAP is the target of a large number of proteins and small regulatory molecules including antibiotics used the treatment of various infectious diseases. The sigma subunit of the bacterial RNAP is implicated in all steps of transcription initiation which is the crucial point of genes expression.For example some of the sigma subunits activate genes of virulence in pathogenic bacteria and are implied in the persistence which is a form of survival to the antibiotic treatments.This project aimed to explore the role of the sigma subunits of RNAP bacterial polymerase in resistance to the lipiarmycine (Fidaxomicin). We used biochemical approaches, biophysics and genetics for the study of the dynamic of the interactions DNA-protein in the complexes formed by RNA polymerase, the antibiotic and the promoter DNA. The results of our study show that sensitivity of RNAP to the drug strongly depends on the structure of the sigma region 3.2 and that the regions 1.2 and 3.2 of the sigma subunit are implied in the formation of the RNAP-promoter open complex. Mutations in these regions allosterically affected action of lipiarmycin by impairing the formation of the open complex.These results suggest that conformation and mobility of the region 3.2 depend on its sequence. The outcomes of our work could be used for development of new more effective drugs and could help to progress the studies of the fundamental mechanisms of the transcription.
19

The novel function of SWAP-70 in hematopoiesis/erythropoiesis

Ripich, Tatsiana 30 November 2009 (has links)
Abstract SWAP-70 originally identified as a signaling protein exclusively expressed in B-cells has been recently described in other cells of the hematopoietic system, such as mast cells and dendritic cells. Here we describe a novel role of SWAP-70 in hematopoiesis, specifically in regulation of erythropoiesis. SWAP-70 protein expression is detected at the stage of the hematopoietic stem cell (HSC). Its expression persists throughout several stages of multipotent and myeloid progenitors. In erythroid development SWAP-70 is found from early committed to erythroid lineage precursors, burst-forming unit erythroid (BFU-E) and colony-forming unit erythroid (CFU-E); however its expression declines with erythroid maturation and it is lastly detectable at the basophilic erythroblast stage. The protein’s deficiency leads to 3-fold increase in HSC numbers in the bone marrow (BM). The lack of SWAP-70 does not affect intermediate myeloid progenitors and the first erythroid committed progenitor, BFU-E. Hematopoietic tissues (BM and spleen) of Swap-70-/- mice carry 2-times less CFU-Es, thus SWAP-70 appears to be important at this stage. Swap-70-/- mice have the same frequencies of later erythroid progenitors, Ter-119+ erythroblasts, in the BM but fewer in the spleen. BM and splenic Ter-119+ erythroid Swap-70-/- compartment (basophilic, polychromatic and orthochromatic erythroblasts) exhibit an altered profile that is characterized by the delayed maturation of cells at the polychromatic stage. SWAP-70 deficiency is not critical for steady state erythropoiesis and does not influence blood homeostasis. Yet SWAP-70 is essential for proper stress response in conditions of anemia. Swap-70-/- mice have normal steady state hematocrite level but fail to restore it after induced anemia, thus showing sluggish blunted response to erythropoietic stress. In resting conditions Swap-70-/- early erythroid progenitors (CFU-Es) exhibit aberrant preactivation of the integrin VLA-4, which supports homotypic and heterotypic interaction within the erythroid niche, and are hyperadhesive to fibronectin. Similarly, Swap-70-/- basophilic erythroblasts are hyperadhesive to splenic tissue. Based on our data and our initial observations we propose a novel function of SWAP-70 in the c-kit signaling pathway and integrin-mediated, i.e. VLA-4, interactions that are important for HSC and erythroid progenitor maintanence and differentiation. Better understanding of mechanisms governing red blood cell development and homeostasis is of high relevance in the context of treatment of anemia, a very common blood disorder, which leads to a wide range of clinical complications and is the most common cancer-associated morbidity.
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Παρασκευή και πιστοποίηση ζωοτροφής για πειραματική μελέτη των επιδράσεων των μετάλλων στις λιπιδαιμίες

Λέκκας, Παναγιώτης 21 July 2015 (has links)
O ψευδάργυρος -Zn ελέγχει τον μεταβολισμό των λιπιδίων και γλυκόζης μέσω Ζn-μεταγραφικών παραγόντων. Δίαιτες υψηλών λιπαρών οδηγούν στην ενδοκυτταρική συσσώρευση ελευθέρων ριζών, μειώνουν την μεταγραφική έκφραση των εκκαθαριστών τους και την ενεργότητα αντιοξειδωτικών ενζύμων και οδηγούν σε μεταβολικό σύνδρομο. Οι πρωτεϊνες του θερμικού shock (Heat shock proteins-HSP) παίζουν σημαντικό ρόλο στην αντίσταση στο κυτταρικό stress ως προσαρμογή ,μετά από έκθεση, σε διάφορα ερεθίσματα. ΣΚΟΠΟΣ : Μελέτη της επίδρασης του διατροφικού Ζn και των Hsp70,στην μεταβονομική των λιπιδίων αίματος και ήπατος ποντικών ΥΛΙΚΟ-ΜΕΘΟΔΟΙ :Ενήλικα αρσενικά ποντίκια: 1. Wild type (Wt) Hybrid (F1/F1) C57Bl/6 x CBA και 2. Transgenic (Tg) human HSP70 overexpressing mice, από ηλικίας ενός μηνός εντάχθηκαν στις παρακάτω διατροφές ,επί 10 εβδομάδες. Διατροφή Αριθμός Wt Αριθμός Tg Chow Diet (30 Zn) 6 10 High Fat Diet (3 Zn) 13 12 High Fat Diet (30 Zn) 9 8 High Fat Diet (300 Zn) 12 12 Σύνθεση των τριών διαιτών υψηλών λιπαρών -HFD: 3mg, 30mg, 300mg Zn /kg τροφής (mucedoola s.r.l Ιtaly-55% Cal από λιπαρά στοιχεία), Chow : δίαιτα ελέγχου Βιοχημικές αναλύσεις: Cholesterol ,Triglycerides ,HDL-cholesterol, Glucose ,Insulin Μετρήσεις μετάλλων και αντιοξειδωτικών παραγόντων: SOD (ερυθρά αιμοσφαίρια ) TAC (ορός αίματος) Zn , Cu (ερυθρά αιμοσφαίρια και ιστός ήπατος) Μεταβονομική ανάλυση και αξιολόγηση λιπιδίων :Εκχύλιση ορού αίματος και ηπατικού ιστού για λήψη Φάσματος 1H-NMR ΣΥΜΠΕΡΑΣΜΑΤΑ 1. Η HF δίαιτα αύξησε σημαντικά ,το τελικό βάρος και τον ρυθμό αύξησης βάρους ,τη χοληστερόλη -CL και την λιποπρωτεϊνη υψηλής πυκνότητας-ΗDL ,την ινσουλίνη –Ins, στα WT & Tg και μείωσε την ολική αντιοξειδωτική ικανότητα-TAC στο πλάσμα και την δραστηριότητα της σουπεροξείδιο-δισμουτάσης-SOD στα ερυθροκύταρα των WΤ και Tg 2. Ο επαρκής διατροφικός Zn (30mg/kgτροφής) φαίνεται να αποτελεί κρίσιμο παράγοντα διαμόρφωσης προστατευτικού ηπατολιπιδαιμικού προφίλ, ποντικών σε υπερλιπιδική δίαιτα. Η αύξηση ή μείωση του Zn σε HFDς φαίνεται να μειώνει την TAC του πλάσματος σε WΤ και Tg ενώ η δραστικότητα της SOD φαίνεται ανάλογη των επιπέδων του Zn Η ανεπάρκεια ή περίσσεια Zn αυξάνει τα αθηρογόνα SFA και μειώνει τα αντι-αθηρογόνα λιπίδια, PC, DU, LA DIAL ,UFA στις HDL, nonHDL και το ήπαρ, στα WΤHFD και στα ΤgHFD 3. Οι HSP70 : Τα διαγονιδιακά ζώα που φέρουν το γονίδιο hHsp70, φαίνεται ότι είτε σε έλλειψη είτε σε περίσσεια Ζn, που συνήθως συνοδεύoνται από μεταβολικό σύνδρομο, κατορθώνουν να διατηρούν καλλίτερους δείκτες λιπιδικού προφίλ σε σχέση με τα WT ζώα. Τα Τg εμφάνισαν σημαντικά χαμηλότερη CL ,TG , HDL σε σύγκριση με τα WT ενώ η HSP70 αύξησε σημαντικά την ενεργότητα της ολικής SOD στα ερυθρά αιμοσφαίρια. Η HSP70 μείωσε τα αθηρογόνα SFA και αύξησε τα αντιαθηρογόνα λιπίδια DIAL, DU, LA, UFA, SM στις HDL, nonHDL , και στο ήπαρ ποντικών που εκτέθηκαν σε HFD και σε όλες τις συγκεντρώσεις Zn. / Zinc –Zn controls lipid and glucose metabolism via Zn-transcription factors. High fat diets –HFDs lead to intracellular free radicals accumulation, decrease the transcriptional expression of their scavengers and anti-oxidative enzymes’ activity leading finally to metabolic syndrome. Heat shock proteins-HSPs play a significant role in cellular resistance response , as an adaptation mechanism, after exposure to various stimuli. SCOPE: To study the effects of nutritional Zn and HSP70s on the metabonomics of serum and liver lipids in mice MATERIALS-METHODS: Male mice: 1. Wild type (Wt) Hybrid (F1/F1) C57Bl/6 x CBA και 2. Transgenic (Tg) human HSP70 overexpressing mice, one month old, were subjected for 10 weeks to the following diets : Diet Number of Wt Number of Tg Chow Diet (30 Zn) 6 10 High Fat Diet (3 Zn) 13 12 High Fat Diet (30 Zn) 9 8 High Fat Diet (300 Zn) 12 12 Composition of the three HF Diets: 3mg, 30mg, 300mg Zn /kg τροφής (mucedoola s.r.l Ιtaly-55% Cal from greasy ingredients),Chow :control diet Biochemical analyses: Cholesterol ,Triglycerides ,HDL-cholesterol, Glucose ,Insulin Metals and antioxidative factors levels: SOD (red blood cells )TAC (blood serum) Zn , Cu (red blood cells and liver tissue) Lipids metabonomics : Blood serum and liver tissue extracts for 1H-NMR spectrum analysis and evaluation CONCLUSIONS 1. HFDiet significantly increased the rate of mice body weight gaining, as well as, cholesterol-CL, high density lipoproteins-HDL, insulin, in WT and Tg mice and decreased plasma total antioxidant capacity-TAC and red blood cell super oxide dismutase –SOD activity , in WT and Tg mice 2.Suficient nutritional Zn (30 mg/kg food) prevails as a crucial modulator of a protective hepato-lipidaemic profil of mice in high fat diet. Zinc deficiency or excessiveness , in HFDiets , decreases plasma TAC in WT and Tg mice, while SOD activity shows proportional to Zn levels. Zinc deficiency or excessiveness increases the atherogenic SFA and decreases the anti –atherogenic lipids : PC, DU, LA DIAL ,UFA, in HDL, nonHDL and liver, in WΤ-HFD and Τg-HFD mice 3. HSP70s : Transgenic mice over-expressing hHsp70 gene and exposed either to Zn deficiency or Zn excessiveness , both driving usually to metabolic syndrome , reveal significantly better lipid profile indicators, comparing to WT mice. Tg mice revealed significantly lower CL , TG , HDL levels compared to WT, while HSP70 in Τg mice significantly increased total SOD activity in red blood cells. HSP70 also decreased the atherogenic SFAs and increased the anti-atherogenic lipids DIAL, DU, LA, UFA, SM in HDL, nonHDL and in the liver of mice exposed to HFDiets and all Zn concentrations

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