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Caracterização de perfis transcricionais de folhas e da região cambial de Eucalyptus grandis usando o SAGE / Caracterization of Eucalyptus grandis leaves and cambial region transcriptomes using SAGEMayra Costa da Cruz Gallo de Carvalho 06 February 2007 (has links)
Apenas muito recentemente estratégias genômicas e pós-genômicas têm sido utilizadas em estudos de espécies arbóreas importantes na silvicultura. Nos países tropicais, a exemplo do Brasil, as espécies de eucalipto são especialmente importantes nos plantios comerciais principalmente destinados à indústria de papel e celulose. O eucalipto é caracterizado por elevadas taxas de crescimento e alta adaptabilidade resultante da interação de mecanismos moleculares e processos metabólicos ainda pouco conhecidos. Nesse sentido, o presente trabalho teve como objetivo principal o estabelecimento de perfis transcricionais comparativos para folhas e para o xilema em formação de árvores de Eucalyptus grandis. grandis. O uso do método SAGE permitiu analisar 5864 genes dos quais 2247 (38%) puderam ser identificados. Foram encontrados 464 genes diferencialmente expressos, sendo 47 exclusivamente expressos na região cambial e 64 nas folhas. Além disso, as estratégias adotadas na identificação tags-genes permitiram que as SAGE tags fossem eficientemente utilizadas na diferenciação de isoformas gênicas tecido-específicas e de localização celular específica. Genes relacionados à fotossíntese, fotorrespiração e destoxificação celular foram preferencialmente encontrados na biblioteca SAGE de folhas, enquanto genes relacionados à síntese da parede celular, organização do citoesqueleto e respiração, foram preferencialmente expressos na biblioteca SAGE de madeira. Os níveis de expressão dos transcritos sugeriram a ocorrência de possíveis mecanismos de controle transcricional comum para grupos de genes funcionalmente relacionados e foram também utilizados para sugestão de genes e processos que representam alvos potenciais para o melhoramento do eucalipto. / Recently genomic and post-genomic strategies have been used to study important tree species in planted forests. In the tropical countries, like Brazil, Eucalyptus species are especially important in commercial plantations destined for the paper and cellulose industry. Eucalyptus species are characterized by their high growth rates and great adaptability resulting from the interaction between molecular mechanisms and metabolic processes that are still uncharacterized. Thus, the main goal of this work was the comparison of the transcriptional profiles from leaves and the cambial region of Eucalyptus grandis trees. The use of SAGE allowed the evaluation of 5864 expressed tags of which 2247 (38%) could be identified. 464 differentially expressed tags were indicated, of which 47 were exclusively expressed in the cambial region library and 64 in the leaf library. Furthermore, the strategies used in the tag mapping process allowed an efficient use of the SAGE tags to distinguish gene isoforms with tissue-specific and/or specific cell localizations. Genes related to photosynthesis, photorespiration and cellular detoxification were preferentially found in the SAGE leaf library, while genes involved in cell wall biosynthesis, cytoskeletal organization and respiration were preferentially expressed in the developing xylem. Transcript expression levels suggested the presence of a common transcriptional control for a few functionally related genes, for example, some lignin related genes. Importantly, transcript expression levels were also used for the identification of target genes and processes potentially useful in future Eucalyptus breeding programs.
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Análise funcional de novos genes candidatos durante a diferenciação eritroide / Sugar signaling in sugarcane and evolution diversificationBranco, Diana Santos, 1983- 31 January 2013 (has links)
Orientadores: Fernando Ferreira Costa, Anderson Ferreira da Cunha / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T17:06:48Z (GMT). No. of bitstreams: 1
Branco_DianaSantos_D.pdf: 12860329 bytes, checksum: 5c5da209d2a41c9596907283c3c9e5e8 (MD5)
Previous issue date: 2013 / Resumo: Os mecanismos moleculares envolvidos no perfil de expressão durante a eritropoese tem sido objeto de numerosas investigações como, por exemplo, o estudo da regulação gênica em células de linhagem eritroide. Esses estudos permitem a identificação de novos genes com potencial participação nesse processo e, adicionalmente, possibilitam um melhor entendimento dos genes já identificados na maturação das células eritroides e que possam estar envolvidos na produção de hemoglobinas. Nosso grupo de pesquisa identificou os diversos genes diferencialmente expressos durante a eritropoese. Dentre eles, os fatores de transcrição, EYA3 e HES6 e a latexina, LX, apresentaram maior expressão na fase final da eritropoese in vitro. Nossos dados sugerem participação dos genes EYA3 e LX, nas fases intermediaria e final da diferenciação eritroide, na expressão dos genes das globinas alfa e gama e na produção de HbF in vitro. Adicionalmente, no modelo in vivo zebrafish, os genes eya1, eya2, eya3, eya4, hes6 e hes13 apresentaram padrão de expressão ubíquo, enquanto que o gene lxn apresentou expressão especifica na ICM, tornando-o o candidato mais promissor para ser silenciado. O silenciamento desse gene em zebrafish apresentou fenótipo anêmico em embriões 72hpf, mas não em 48hpf, sugerindo que a anemia e decorrente de um processo no final da diferenciação eritroide, corroborando os dados encontrados em cultura in vitro. Estudos adicionais são necessários para compreensão dos mecanismos e vias envolvidos na participação do gene LX, durante o processo de diferenciação eritroide. Outros genes com potencial participação no processo de eritropoese são CLPX, TRAK2 E GFI. O gene CLPX codifica a caseinolytic peptidase X, uma proteína xvii altamente conservada durante a evolução e que apresenta função de chaperona dependente de ATP. Os dados deste trabalho mostram que o silenciamento do gene clpx1 reduziu significativamente os níveis de hemoglobinizacao e produção de eritrócitos em zebrafish. Contudo, estudos adicionais para o gene clpx2 precisam ser realizados para melhor compreender a possível função desses genes na produção de Heme. O gene TRAK2, por sua vez, e uma Trafficking Protein, Kinesin-Binding 2, envolvida no movimento da mitocôndria ao longo dos microtubulos. Os resultados obtidos em colaboração com o pesquisador Jeffrey Miller, M.D. (NIH/NIDDK) mostraram envolvimento desse gene na eritropoese em modelo in vitro de cultura primaria. No presente estudo, dentre os ortologos para o gene TRAK2 humano avaliados, apenas o trak1.1 parece ter sua função conservada nos teleósteos. O silenciamento desse gene gerou fenótipo anêmico nos embriões avaliados, corroborando os dados obtidos originalmente em cultura de células primaria. Finalmente, os fatores de transcrição de zebrafish gfi1aa, gfi1ab e gfi1b, ortologos aos fatores de transcrição da família Grow Factor Independence (GFI) em humanos também tiveram seu papel avaliado na hematopoese. Nossos dados mostram participação de gf1aa fase inicial de hematopoese e de gf1b na hematopoese definitiva. Também foi determinada a relação epistática entre os fatores gfi e os fatores de transcrição chave hematopoiéticos, mostrando que gfi1aa e gfi1b, juntamente com lmo2, scl, runx-1 e c-myb atuam como reguladores de HSPC em teleósteos / Abstract: Molecular mechanisms involved in expression profile during erythropoiesis have been the subject of numerous investigations such study of gene regulation in erythroid cell culture. These studies allow us to identify new genes potentially involved in erythroid differentiation and additionally to investigate genes already known as regulators of red blood cells and hemoglobin production. Our research group identified several genes differentially expressed during erythropoiesis. Among them, the transcription factors, EYA3 and HES6 and the latexin, LX, were found to have higher expression in the final phase of the in vitro erythropoiesis. Our data suggest that EYA3 and LX, are involved in the intermediate and final stages of erythropoiesis, expression pattern of alfa and gama globin and HbF production in vitro. Additionally in zebrafish model, eya1, eya2, eya3, eya4, hes6 and hes13 showed a ubiquitous expression pattern, while lxn showed specific expression in the ICM, making it the most promising candidate to be knockdowned. lxn knockdown in zebrafish showed anemic phenotype at 72hpf embryos, but not at 48hpf, suggesting that the anemia results is due to a process in the end of the erythroid differentiation, corroborating the results found for in vitro cultures. Additional studies are necessary to understand the mechanisms and pathways involved in the participation of the LX, gene during the process of erythroid differentiation. CLPX, TRAK2 and GFI transcription factors are also potentially candidates to be involved in erythropoiesis. CLPX gene codes for caseinolytic peptidase X, a protein highly conserved during evolution, which presents an ATP-dependent chaperone function. Data from this study showed that clpx1 knockdown reduced significantly hemoglobinization levels and erythroid production in zebrafish. However, future studies xv for the clpx2 gene is needed to better understand the function of these genes in the heme production. TRAK2 gene, in turn, is a Trafficking Protein, Kinesin-Binding 2, involved in mitochondrial movement along microtubules. Results obtained in collaboration with the researcher Jeffrey Miller, M.D. (NIH/NIDDK), showed the involvement of this gene in erythropoiesis in primary culture in vitro models. In this study, from the orthologs for the human TRAK2 gene analyzed, only trak1.1 appears to have its function conserved in teleosts. The silencing of this gene generated anemic phenotype in the embryos tested, corroborating the original results obtained in primary cell culture. Finally, gfi1aa, gfi1ab and gfi1b zebrafish transcription factors, orthologous to the Grow Factor Independence (GFI) family transcription factors in humans, also had their function evaluated in hematopoiesis. Our data suggest is involved in the initial phase of hematopoiesis while gf1b has a role in the definite hematopoiesis. The epistatic relation between the gfi and the hematopoietic key transcription factors was also determined, showing that gfi1aa and gfi1b, together with lmo2, scl, runx-1 and c-myb also act as regulators of HSPC in teleosts / Doutorado / Genetica Vegetal e Melhoramento / Doutora em Genética e Biologia Molecular
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Formation initiale au raisonnement clinique en sciences maïeutiques : Bénéfices, limites et perspectives d'utilisation des cartes conceptuelles / Initial training to clinical reasoning in midwifery : Advantages, limits and perspectives of concept mappingDemeester, Anne 19 December 2014 (has links)
Introduction. Le raisonnement clinique (RC) est une compétence médicale clé. Cette thèse soutient que l'organisation et la mise en lien systématique et explicite entre les données d'une patiente ou d'un nouveau-né et les connaissances d'un étudiant améliore sa performance dans la résolution de cas cliniques courants de la pratique sage-femme. Objectifs. Identifier les difficultés de RC d'étudiants en maïeutique et leurs causes explicatives ; identifier l'utilisation des cartes conceptuelles (CC) en lien avec le raisonnement clinique ; solliciter le RC des étudiants par la résolution de cas cliniques courants, identifier leurs perceptions et analyser leurs performances en fonction de leur niveau d'acquisition des CC.Méthodes. Etude exploratoire mixte, revue de la littérature, et expérimentation auprès de 97 étudiants de trois écoles de maïeutique. Analyse de 570 questionnaires et 352 CC. Résultats. Sept causes de difficultés de RC identifiées, parmi lesquelles le défaut de mise en liens entre les connaissances. Le potentiel d'utilisation des CC est confirmé par la littérature. L'expérimentation montre l'acceptabilité des CC et une aide à la résolution dans 50% des cas. Il existe un lien entre la maîtrise des CC, la cohérence du RC et le niveau de performance de résolution des cas. Cette dernière dépend de la représentation initiale du cas (concept de départ) et de la hiérarchisation des concepts, mais pas de la forme de la CC. Les CC permettent également d'identifier les difficultés des étudiants et d'établir un diagnostic pédagogique. Conclusion. La recherche valide l'hypothèse de départ et débouche sur des propositions pour utiliser les CC dans la formation au RC. / Introduction. Clinical reasoning (CR) is a key competence that students in health sciences must acquire. This thesis argues that concept mapping improves midwives students' performance in clinical problem solving. Objectives. Identify midwives students CR difficulties and their explanatory causes; identify the use of concept mapping and show compatibility between concept mapping and recommendations for clinical reasoning; introduce concept maps (CMs) in clinical solving learning sessions and observe their effects.Methods. Mixed exploratory study, literature review and experimentation including 97 students nested in three schools of midwifery: 570 questionnaires and 352 CMs were analysed. Results. Seven causes of CR difficulties were identified. Literature confirms CMs may be a relevant tool for clinical reasoning teaching and learning. By making knowledge explicit CM helps one out of two students to improve clinical problem solving performance when CM include a correct core concept and when concepts are hierarchically organized. The best performing students are those who acquire the construction of CMs.Conclusion. The research validates the starting assumption and leads to proposals of using CMs in CR learning. Concept mapping might be an interesting activity to foster CR and identify the difficulties that students may encounter.
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Ação antioxidante de extratos de especiarias e suas misturas binárias e ternárias sobre a estabilidade oxidativa de óleo de soja / Antioxidant activity of spices extracts and their binary and ternary mixtures on soybean oil oxidative stabilityMarilis Yoshie Hayashi Shimano 01 October 2012 (has links)
A oxidação de lipídeos produz compostos indesejáveis que alteram as características organolépticas de alimentos lipídicos e reduzem a qualidade nutricional. Nas indústrias alimentícia, cosmética e farmacêutica são adicionados antioxidantes sintéticos para retardar ou prevenir a deterioração lipídica. Devido aos estudos sobre a possível toxicidade dos antioxidantes sintéticos e ao apelo por compostos ativos naturais, o uso de antioxidantes naturais presentes em ervas e especiarias representa uma alternativa promissora. No presente trabalho foram estudadas as condições de obtenção de extratos hidroalcoólicos de especiarias e sua aplicação em óleo de soja refinado em teste acelerado. O estudo do efeito da temperatura e do grau de hidratação do etanol sobre o teor de compostos fenólicos totais dos extratos de alecrim, orégano, sálvia e tomilho foi realizado com aplicação de planejamento experimental e metodologia de superfícies de resposta. As condições para uma extração eficiente dos compostos fenólicos de alecrim e tomilho desidratados foram o uso de etanol 50% (v/v) e temperatura entre 45 a 50°C. Extrato de sálvia com maiores concentrações em fenólicos totais foram obtidos com etanol 50% (v/v) em uma faixa de temperatura de 57,5 a 60°C. O extrato de orégano requer uso de etanol 40-50% (v/v), em qualquer temperatura na faixa estudada (30 a 60°C). Os compostos identificados por cromatografia gasosa acoplada à espectrometria de massas foram os ácidos cafeico e dihidrocafeico, timol e arbutina. Os extratos de alecrim, orégano e tomilho preparados nas condições otimizadas, bem como suas misturas binárias e ternárias, foram adicionados ao óleo de soja refinado e submetidos a teste acelerado em estufa a 60°C. Os resultados de Índice de Peróxido e Absortividade na faixa do ultravioleta evidenciaram que as misturas de extratos foram capazes de oferecer proteção antioxidante ao óleo de soja refinado. Combinações com alecrim apresentaram os melhores efeitos protetores, sendo a melhor combinação das proporções 15% de tomilho, 65% de alecrim e 20% de orégano, totalizando 100 mg de compostos fenólicos totais/g de óleo. / The lipid oxidation produces undesirable compounds that alter the organoleptic characteristics of food lipids and reduce the nutritional quality. In the food, cosmetics and pharmaceutical industries, synthetic antioxidants are added to retard or prevent the lipid deterioration. Due to the possible toxicity of synthetic antioxidants and the call for active natural compounds, the use of natural antioxidants present in herbs and spices is a promising alternative. Thus, this study evaluated the antioxidant activity of extracts of spices and their mixtures on refined soybean oil. The study of temperature and solvent mixture effects on the phenolic extraction from dried rosemary, oregano, sage and thyme was performed according to response surface methodology and mathematical models. The conditions for an efficient extraction of the phenolic compounds from rosemary and thyme were ethanol 50% at 45-50°C; from sage was ethanol 50% at a temperature range from 57.5 to 60°C, and from oregano was ethanol 40-50% at any temperature in the studied range (30- 60°C). The compounds identified by gas chromatography-mass spectrometry were dihydrocaffeic and caffeic acids, thymol and arbutin. Selected hydroalcoholic extracts of rosemary, oregano and thyme were added to soybean oil subjected to accelerated storage tests. Peroxide values and absorptivity at UV showed that mixtures of extracts were able to provide antioxidant protection to soybean oil. Mixtures with rosemary showed better protective effects than the others. The region of the surface response of the mixtures in which the best protection is offered lies in the proportions of rosemary from 0.50 to 0.80, 0.10 to 0.30 of oregano and thyme from 0.05 to 0.30, in a total of 100 mf GAE/g oil.
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Satisfaction au travail des sages femmes et qualité des soins obstétricaux : une étude au SénégalFaye, Adama 04 1900 (has links)
No description available.
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L’expérience de la maternité des Ouagalaises : d’une génération à l’autreLewis, Marie-Josée 08 1900 (has links)
No description available.
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Die „Teufelskanzel“ im Spreepark zu Neusalza-SprembergMohr, Lutz 27 February 2018 (has links)
No description available.
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Sclareol biosynthesis in clary sage and its regulation / Biosynthèse du sclaréol et sa régulation chez la sauge sclaréeChalvin, Camille 12 July 2019 (has links)
Le sclaréol est un diterpène produit par les organes floraux de la sauge sclarée (Salvia sclarea, Lamiaceae). Il est utilisé en parfumerie pour l’hémisynthèse de l’ambroxide, une substance caractérisée par une odeur ambrée et une grande capacité de fixation des parfums. L’augmentation de la demande mondiale en sclaréol stimule actuellement les tentatives d’accroître le rendement de la production de sclaréol à partir de la sauge sclarée. L’objectif du travail présenté dans ce manuscrit était d’améliorer notre compréhension de la biosynthèse du sclaréol et de sa régulation chez la sauge sclarée, afin de mettre en évidence des stratégies d’augmentation du contenu en sclaréol de la sauge sclarée. L'analyse de la surface des calices de sauge sclarée par imagerie par spectrométrie de masse suggère que le sclaréol est principalement sécrété par des structures épidermiques spécialisées appelées trichomes glandulaires. De plus, nous avons mis en évidence les contributions respectives des deux voies de biosynthèse des terpènes présentes chez les plantes, les voies MVA et MEP, à la biosynthèse de trois terpènes de la sauge sclarée. Des expériences de marquage au ¹³C indiquent que le sclaréol et l’acétate de linalyle sont tous deux issus de la voie MEP, alors que le β-caryophyllène semble être d’origine mixte. Nous avons également étudié le rôle potentiel d’une phytohormone, le méthyljasmonate, dans la régulation de la production de sclaréol chez la sauge sclarée. Enfin, nous avons exploré la diversité génétique et phénotypique de populations croates de sauge sclarée sauvage, et montrons que ces populations représentent une ressource génétique distincte par rapport aux populations de référence. L’ensemble de ces résultats met en évidence des pistes prometteuses pour l'amélioration génétique ciblée des performances de la sauge sclarée. / Sclareol is a diterpene produced by floral organs of clary sage (Salvia sclarea, Lamiaceae). It is used in perfume industry for the hemisynthesis of ambroxide, a high-valued perfume component characterized by an amber scent and a high perfume fixation capacity. The global demand for sclareol currently rises, prompting attempts at increasing the yield of sclareol production from clary sage. The purpose of the work presented in this manuscript was to improve knowledge on sclareol biosynthesis and its regulation in clary sage, in order to highlight strategies aiming at enhancing clary sage sclareol content. The analysis of the surface of clary sage calyces by mass spectrometry imaging suggests that sclareol is mainly secreted by specialized epidermal structures called glandular trichomes. Moreover, we have highlighted the respective contributions of the two terpenoid biosynthesis pathways present in plants, MVA and MEP pathways, to the biosynthesis of three terpenoids of clary sage. ¹³C-labeling experiments indicate that sclareol and linalyl acetate both originate from the MEP pathway, whereas β-caryophyllene seems to be of mixed origin. We have also investigated the potential role of a phytohormone, methyljasmonate, in the regulation of sclareol production in clary sage. Finally, we have explored the genetic and phenotypic diversity of Croatian wild clary sage populations and show that these populations represent a distinct genetic resource compared to reference populations. Taken together, these results highlight promising avenues for targeted genetic enhancement of clary sage performances.
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Habitat Selection of Greater Sage-Grouse Centrocercus urophasianus and Northern River Otters Lontra canadensis in UtahWestover, Matthew D. 06 December 2012 (has links) (PDF)
Greater sage-grouse populations have decreased steadily since European settlement in western North America. Reduced availability of brood-rearing habitat has been identified as a limiting factor for many populations. We used radio-telemetry to acquire locations of sage-grouse broods from 1998 to 2012 in Strawberry Valley, Utah. Using these locations and remotely-sensed imagery, we proceeded to 1) determine which features of brood-rearing habitat could be identified using widely available, fine-scale imagery 2) assess the scale at which sage-grouse selected brood-rearing habitat in our study area, and 3) create a predictive habitat model that could be applied across our large study area to identify areas of preferred brood-rearing habitat. We used AIC model selection to evaluate support for a list of variables derived from remotely-sensed imagery. We examined the relationship of explanatory variables at three scales (45, 200, and 795 meter radii). Our top model included 10 variables (percent shrub, percent grass, percent tree, percent paved road, percent riparian, meters of sage/tree edge, meters of riparian/tree edge, distance to tree, distance to transmission lines, and distance to permanent structures). Variables from each scale were represented in our top model with the majority of scale-sensitive variables suggesting selection at the larger (795 meter) scale. When applied to our study area our top model predicted 75% of naive brood locations suggesting reasonable success using this method and widely available NAIP (National Agricultural Imagery Program) imagery. We encourage application of this method to other sage-grouse populations and species of conservation concern. The northern river otter is a cryptic semi-aquatic predator that establishes and uses latrines. Highly used river otter latrines indicate otter "activity centers" since frequency of scat deposition is thought to be correlated to frequency of habitat use. We compared an indirect method (scat counts) and a direct method (remote cameras) of determining latrine utilization in order to assess the accuracy of the commonly used indirect method. To further compare these methods we used them to examine effects of anthropogenic disturbance on otters of the Provo River in Utah. We found that overall the direct and indirect methods were highly correlated. There was significant seasonal variation in the degree of correlation between the indirect and direct methods with correlation being significantly higher in the summer. We found similar results when using these methods to examine effects of anthropogenic disturbance. For each method the distance of the latrine to trails was significant in one of the top competing models. We suggest that space use of otters in our study area is being affected by anthropogenic disturbance as measured by distance to trails. We also suggest that scat counts should only be conducted during the summer when they correlate best with actual levels of otter activity.
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Der Riese Sprejnik und der Wassermann der SpreeMohr, Lutz 06 March 2018 (has links)
No description available.
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