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1

Yang, Qing. "Effect of maturation on nerve excitability in an experimental model of threshold electrotonus." Kyoto University, 2000. http://hdl.handle.net/2433/180851.

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Lippow, Shaun Matthew. "Computational analysis, design, and experimental validation of antibody binding affinity improvements beyond in vivo maturation." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/38886.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2007.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Includes bibliographical references (leaves 98-110).<br>This thesis presents novel methods for the analysis and design of high-affinity protein interactions using a combination of high-resolution structural data and physics-based molecular models. First, computational analysis was used to investigate the molecular basis for the affinity improvement of over 1000-fold of the fluorescein-binding antibody variant 4M5.3, engineered previously from the antibody 4-4-20 using directed evolution. Electrostatic calculations revealed mechanistic hypotheses for the role of four mutations in a portion of the improvement, subsequently validated by separate biochemical experiments. Next, methods were developed to computationally redesign protein interactions in order to rationally improve binding affinity. In the anti-lysozyme model antibody D1.3, modest binding improvements were achieved, with the results indicating potentially increased sucesss using predictions that emphasize electrostatics, as well as the need to address the over-prediction of large amino acids. New methods, taking advantage of the computed electrostatics of binding, yielded robust and significant improvements for both model and therapeutic antibodies.<br>(cont.) The antibody D44.1 was improved 140-fold to 30 pM, and the FDA-approved antibody cetuximab (Erbitux) was improved 10-fold to 52 pM, with an experimental success rate of greater than 60% for single mutations designed to remove undersatisfied polar groups or improve misbalanced electrostatic interactions. Finally, a physics-based improvement to the calculation of the nonpolar component of solvation free energy was implemented and parameterized to address the over-prediction of large amino acids. These results demonstrate novel computational capabilities and indicate their applicability for enhancing and accelerating development of reagents and therapeutics.<br>by Shaun Matthew Lippow.<br>Ph.D.
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Bernal, Ulloa Sandra Milena [Verfasser]. "Experimental studies into the role of cAMP in bovine oocyte maturation and embryo developmental competence / Sandra Milena Bernal Ulloa." Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2016. http://d-nb.info/1104288443/34.

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4

Listopad, Joanna Jadwiga. "HO-1 induction by Co-PPIX suppresses experimental skin inflammation, T cell immunity and dendritic cell maturation and function." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2007. http://dx.doi.org/10.18452/15601.

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Die Hämoxygenase 1 (HO-1) ist ein Stressprotein mit antientzündlichen, immunsupprimierenden und zytoprotektiven Eigenschaften, welche in vielen Tiermodellen nachgewiesen wurden. Die zugrunde liegenden Mechanismen sind wenig bekannt. Diese Arbeit demonstriert erstmalig, dass die physiologische Induktion von HO-1 wichtig für die Limitierung von T-Zell-abhängigen Hautentzündungen ist. So führt der HO-1-Inhibitor, Zinn-Protoporphyrin IX (Sn-PPIX), zu einer verstärkten Hautentzündung im Mausmodell. Die pharmakologische Induktion von HO-1 durch Kobalt-Protoporphyrin IX, Co-PPIX, hemmt dagegen die Entzündung in DNFB- bzw. TMA-induzierten murinen Kontaktallergiemodellen sowohl bei Verabreichung von Co-PPIX während der Sensibilisierung als auch vor der Auslösung. Bemerkenswerterweise hemmt eine Co-PPIX-Behandlung die Antigen-induzierte T-Zellproliferation ex vivo in Milzzellen von behandelten Mäusen und in vitro in humanen mononukleären Zellen des peripheren Blutes. Da eine HO-1-Induktion durch Co-PPIX nur in Monozyten und in aus Monozyten abgeleiteten myloischen Dendritischen Zellen (MDDC), nicht aber in T-Zellen, beobachtet wurde, fokussierten alle weiteren Untersuchungen auf Antigen-präsentierende Zellen. HO-1-Induktion durch Co-PPIX reduziert die Expression von MHC-Klasse II und akzessorischen Molekülen und steigert die Phagozytose und den oxidativen Burst von Monozyten. Die immunphänotypische Differenzierung und Maturierung von MDDC wird gehemmt. Funktionsteste zeigen eine Reduktion der Expression und Sekretion von proinflammatorischen und immunstimulatorischen Zytokinen, während die Sekretion des antientzündlichen Zytokins IL-10 gesteigert ist. Die Fähigkeit der MDDC zur Antigenpräsentation gegenüber T-Helferzellen ist für Allo- und Recallantigene stark herabgesetzt. Mittels adenoviraler HO-1-Transduktion von MDDC konnte die Spezifität der Effekte bestätigt werden. Diese Daten zeigen, dass eine verstärkte HO-1-Aktivität die Dendritischen Zellen zu einem unreifen und immunkompromittierten Phänotyp verändert und weisen darauf hin, dass die HO-1-Induktion einen wichtigen Ansatz für die Hemmung der zellulären Immunität und für die Behandlung von T-Zell-abhängigen Hautentzündungen darstellt.<br>Heme oxygenase 1 (HO-1) is an antiinflammatory stress protein. Its immunosuppressive and cytoprotective activities have been demonstrated in several animal models. The underlying mechanisms, however, are poorly understood. This study demonstrates for the first time that the physiological induction of HO-1 is important for the limitation and resolution of T cell-dependent skin inflammation. So, the HO-1 inhibitor, tin protoporphyrin IX (Sn-PPIX), augments cutaneous inflammation in mouse model. Moreover, pharmacologic HO-1 induction by the potent HO-1 inducer, cobaltic protoporphyrin IX (Co-PPIX), inhibits inflammation when applied around sensitization or before challenge in murine DNFB- and TMA-induced contact hypersensitivity models. Remarkably, Co-PPIX treatment inhibits antigen-driven T cell proliferation both ex vivo in murine splenocytes and in vitro in human peripheral blood mononuclear cells. Since induction of HO-1 mRNA and protein was found in monocytes and monocyte-derived myeloid dendritic cells (MDDC) but not T cells, further investigations focused on antigen-presenting cells. HO-1 induction by Co-PPIX depresses monocytic MHC class II and accessory molecule expression whereas phagocytosis and respiratory burst activities are augmented. Moreover, HO-1 induction inhibits the immunophenotypic differentiation and maturation of MDDC. Functional analysis revealed a decreased proinflammatory cytokine production whereas secretion of the antiinflammatory cytokine IL-10 is increased. Remarkably, the antigen-presenting capacity of MDDC for T-helper cells is diminished both for allo- and for recall-antigens. Adenoviral HO-1 transduction of MDDC confirmed that the effects are mediated by HO-1. These data indicate that an enhanced HO-1 activity switches myeloid DCs to an immature and functionally compromised phenotype and suggest that HO-1 induction represents an important approach for depressing T cell immunity and for the treatment of T cell-dependent skin inflammation.
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FARIAS, Emanuel Tarcisio do Rêgo. "Compostos bioativos e capacidade antioxidante em frutos de araçá, noni e romã." Universidade Federal de Campina Grande, 2014. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/835.

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Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-05-29T12:38:02Z No. of bitstreams: 1 EMANUEL TARCISIO DO RÊGO FARIAS - DISSERTAÇÃO PPGSA PROFISSIONAL 2014..pdf: 1539206 bytes, checksum: eeac3c1656f48100210a881ec09ef1c6 (MD5)<br>Made available in DSpace on 2018-05-29T12:38:02Z (GMT). No. of bitstreams: 1 EMANUEL TARCISIO DO RÊGO FARIAS - DISSERTAÇÃO PPGSA PROFISSIONAL 2014..pdf: 1539206 bytes, checksum: eeac3c1656f48100210a881ec09ef1c6 (MD5) Previous issue date: 2014<br>O consumo de frutas in natura é crescente em todo o mundo devido a fatores que levam a modificações nos hábitos alimentares das pessoas, como o cuidado com a saúde e os aspectos nutritivos dos alimentos. O presente trabalho teve como objetivo avaliar a qualidade, quantificar os compostos bioativos e a capacidade antioxidante dos frutos: araçá, noni e romã. O trabalho foi desenvolvido no Laboratório de Tecnologia de Produtos de Origem Vegetal do CCTA/UFCG, no Campus de Pombal - PB. Frutos do araçazeiro, do noni e da romãzeira foram provenientes de plantios localizados em cidades distintas (Areia-PB, Fortaleza-CE e Sousa-PB, respectivamente). Os frutos foram colhidos diretamente na copa da planta, tomando-se como índice de colheita a coloração do fruto. Foram avaliados quatro e cinco estádios de maturação para os frutos de araçá e noni, respectivamente. Foram realizadas avaliações físicas, físico-químicas, compostos bioativos e capacidade antioxidante nos frutos. O delineamento experimental utilizado foi o inteiramente casualizado. Os resultados foram submetidos à análise de variância, detectando efeito significativo para o teste F, às médias foram comparadas pelo teste de Tukey ao nível de 5% de probabilidade. As características físico-químicas de sólidos solúveis, açúcares solúveis totais, açúcares redutores e relação SS/AT, aumentaram com o avanço da maturação para os três frutos estudados. Para os compostos bioativos: o teor de ácido ascórbico dos frutos de noni apresentou um aumento considerável com o avanço da maturação; o teor de antocianinas da romã aumentou com a maturação, assim como os compostos fenólicos do araçá apresentou valores máximos para o estádio I e teve uma redução de mais de 50% no estádio IV, os frutos de noni e romã também apresentaram valores representativos para os compostos fenólicos. Os frutos estudados apresentaram propriedade antioxidante, entretanto a ação foi diferenciada entre eles, o araçá apresentou a maior capacidade de reduzir o radical DPPH e teve sua capacidade reduzida com o avanço da maturação, o noni apresentou efeito contrário aumentando o poder redutor com o desenvolvimento dos frutos e a romã não apresentou variação entre os estádios de maturação. Concluindo que os frutos avaliados apresentaram quantidades consideráveis de compostos biologicamente ativos, podendo constituir como uma boa fonte de antioxidantes naturais para a dieta humana.<br>The consumption of fresh fruits is increasing worldwide due to factors that lead to changes in eating habits of people, such as health care and nutritional aspects of food. This study aimed to evaluate the quality, quantify the bioactive compounds and the antioxidant capacity of fruits: guava, noni and pomegranate. The work was developed in the Laboratory of Technology of Plant Products of CCTA / UFCG, Campus de Pombal - PB. Fruits of strawberry guava, noni and pomegranate were from plantations located in different cities (Areia-PB, Fortaleza-CE and Sousa-PB, respectively). The fruits were harvested directly in the crown of the plant, taking as harvest index coloring of the fruit. Four five maturity stages were evaluated for the fruits of guava and noni, respectively. Physical assessments, physicochemical, bioactive compounds and antioxidant capacity in fruits were performed. The experimental design was completely randomized. The results were subjected to analysis of variance, detecting significant for the F test, the average effect were compared by Tukey test at 5% probability. The physico-chemical characteristics of soluble solids, total soluble sugars, reducing sugars and SS / TA ratio increased with advancing maturity for the three studied fruits. For bioactive compounds: the ascorbic acid content of the fruits of noni showed a significant increase with advancing maturity; the anthocyanin content of pomegranate increased with maturation, as well as phenolic compounds of guava showed maximum values for stage I and decreased by more than 50% in stage IV, the fruits of noni and pomegranate also had representative values for phenolic compounds. The fruits studied exhibited antioxidant property however the action was different between them, guava showed the greatest ability to reduce DPPH radical and had reduced capacity with advancing maturity, noni showed opposite effect by increasing the reducing power with the development of pomegranate fruit and did not vary between the maturity stages. Concluding that the fruits evaluated showers considerables amounts of biologically active compounds may be a good source of natural antioxidants for the human diet.
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Elie, Marcel. "Effets des conditions temps-température et de la matrice minérale sur l'évolution de matières organiques de type II et III au cours de la pyrolyse en milieu confiné." Nancy 1, 1994. http://www.theses.fr/1994NAN10315.

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Une roche mère du toarcien du bassin de paris (broyée, sèche, humide), son kérogène isole et un charbon de la Mahakam ont été matur2s artificiellement en milieu confiné afin d'étudier les effets de la présence de matrice minérale, de la présence d'eau et du couple temps-température lors de la maturation thermique de la matière organique. 224 pyrolyses ont été réalisées sur ces différents précurseurs dans des conditions temps-température variables: 5 heures < t < 100 jours ; 203c < t < 508c. Les résultats obtenus indiquent que: la plupart des paramètres géochimiques sont décalés entre le kérogène et la roche mère en raison des propriétés de rétention des minéraux argileux ; l'influence catalytique des minéraux argileux est plus faible pour une roche mère que pour un mélange artificielle (kérogène + minéraux argileux) ; la présence d'eau (12%) induit un enrichissement du bitume résiduel en hydrocarbures ; l'eau intervient directement dans les processus de transfert d'hydrogène lors de la dégradation de la matière organique en milieu confiné ; le temps et la température ne sont pas des paramètres interchangeables. En effet, la dégradation des composes polaires s'intensifie avec la durée de pyrolyse alors que la dégradation des hydrocarbures est plus sensible à l'utilisation de températures élevées. Ces résultats montrent la nécessité de prendre en compte les différents facteurs (présence de matrice minérale, rôle de l'eau, effets combinés du temps et de la température) dés lors qu'il s'agit d'extrapoler
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FOTUNATO, Tádria Cristiane de Sousa. "Propriedades físicas, químicas e capacidade antioxidante da romã (cv.molar) durante o desenvolvimento do fruto." Universidade Federal de Campina Grande, 2016. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/744.

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Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-05-18T19:03:54Z No. of bitstreams: 1 TADRIA CRISTIANE - DISSERTAÇÃO PPGHT 2016.pdf: 1674149 bytes, checksum: 0fdd10430fee76dc5ec09dd880c9bbda (MD5)<br>Made available in DSpace on 2018-05-18T19:03:54Z (GMT). No. of bitstreams: 1 TADRIA CRISTIANE - DISSERTAÇÃO PPGHT 2016.pdf: 1674149 bytes, checksum: 0fdd10430fee76dc5ec09dd880c9bbda (MD5) Previous issue date: 2016-05-25<br>A caracterização das transformações que ocorrem durante o desenvolvimento do fruto possibilita identificar o período em que os frutos reúnem o maior número de características que expressam a qualidade do fruto para a comercialização in natura ou industrial. Assim o objetivo deste estudo foi quantificar as mudanças nas características físicas, físico-químicas e atividade antioxidante do suco e rendimento de óleo e amido da semente da romã cv.‗Molar‘, durante o desenvolvimento do fruto. O delineamento experimental foi o inteiramente casualizado, cujos tratamentos foram constituídos pela idade dos frutos (10, 20, 30, 40, 50, 60, 70, 80, 90 e 100 dias após a antese), com quatro repetições constituídas por cinco frutos por parcela totalizando 20 frutos por tratamento. Após a colheita os frutos foram transportados para o Laboratório de Análises de Alimentos da Universidade Federal de Campina Grande (UFCG), Campus de Pombal-PB, onde foram realizadas as análises físicas, físico-químicas, atividades antioxidantes do suco. A análise de rendimento de óleo e amido das sementes foi realizada pelo Laboratório Instituto Tamanduá, Patos-PB. Ao longo do desenvolvimento ocorreram alterações nas características físicas, físico-química, atividade antioxidante e de rendimento do óleo e amido da semente. Romãs cv. ‗Molar‘ tiveram uma massa de 200 g, formato oblíquo, no que diz respeito a variável volume do fruto constatouse aumento até os 100 dias de idade. Os frutos apresentaram alteração na coloração da casca a partir dos 50 dias sendo que aos 90 dias os frutos apresentaram coloração amarelo-alaranjado. No suco houve evolução da cor para um rosa avermelhado com redução da intensidade com o avanço da idade. Para as análises químicas constatou-se redução da acidez titulável (AT) a partir dos 80 dias enquanto que no mesmo período houve aumento no teor de SS, SS/AT, açúcares totais e redutores e vitamina C com o desenvolvimento do fruto. No que diz respeito aos pigmentos, fenólicos, antocianinas e carotenoides, verificou-se que com o aumento da idade dos frutos, a concentração de fenólicos diminui linearmente, enquanto que a concentração de antocianinas ocorreu um aumento polinomial atingido concentração máxima aos 90 dias apresentando-se uma coloração avermelhada, ao mesmo tempo os carotenoides apresentaram a menor concentração aos 90 dias de idade com valor de 0,18 µL/100 mL-1 . O tratamento de 90 dias foi o que apresentou a maior capacidade antioxidante com valores de 3501,00 g.polpa.100 mL de DPPH e 10546,52 uM Trolox/g polpa para os métodos DPPH e ABTS respectivamente, revelando alta atividade antioxidante dos frutos nesse período. Rendimento do óleo e amido da semente alterou-se significativamente durante o desenvolvimento do fruto da romã. Houve acréscimo de 11,57% no rendimento de óleo dos 60 para os 100 dias após a antese, em contra partida ocorreu um decréscimo no rendimento de amido tendo o menor rendimento nos frutos colhidos aos 100 dias (12,97%). Diante dos resultados obtidos observa-se que os frutos colhidos aos 90 dias reuniram o maior número de características de qualidade, que juntas possibilitaram identificar a idade na qual os frutos encontram-se aptos a serem colhidos, nas condições de cultivo das Várzeas de Sousa, PB.<br>The characterization of the transformations that take place during the fruit development of the result makes possible to identify the period in which the results join the biggest number of characteristics that express the quality of the result for the marketing in natura or industrial. So the objective of this study quantified the changes in the physical characteristics, chemicalphysically and antioxidant activity of the juice and profit of oil and starch of the seed of the pomegranate hp.'Molar‘, during the development of the result. The experimental delineation was it completely casualizado, whose treatments were constituted by the age of the results (10, 20, 30, 40, 50, 60, 70, 80, 90 and 100 days after the antese), with four repetitions constituted by five results by piece totalizing 20 results for treatment. After the harvest the results were transported for the Laboratory of Analyses of Foods of the Federal University of Big Prairie (UFCG), Campus Of - PB, where the physical analyses were carried out, chemical-physically, antioxidant activities of the juice. The analysis of profit of oil and starch of the seeds was carried out by the Laboratory Institute Anteater, - PB. Along the development alterations took place in the physical characteristics, chemical-physically, antioxidant activity and of profit of the oil and starch of the seed. Pomegranates hp. ‗Molar‗ they had a mass of 200 g, oblique format, what concerns variable volume of the result increase was noted up to 100 days of age. The results presented alteration in the coloration of the bark from 50 days being that to 90 days the results presented coloration orangey-yellow. In the juice there was evolution of the color for a rose reddened with reduction of the intensity with the advancement of the age. For the chemical analyses (AT) noted reduction of the acidity titulável from 80 days whereas in the same period there was increase in the tenor of SS, SS/AT, total and reducing sugars and vitamin C with the development of the result. What concerns the pigments, fenólicos, antocianinas and carotenoides, happened what with the increase of the age of the results, the concentration of fenólicos reduces linearly, whereas the concentration of antocianinas took place an increase polinomial when the very concentration was reached to 90 days when a reddish coloration is showing up, at the same time the carotenoides presented the least concentration to 90 days of age with value of 0,18 µL/100 mL-1. The treatment of 90 days was what pulp presented the biggest antioxidant capacity with values of 3501,00 g.polpa.100 mL of DPPH and 10546,52 a Trolox/g for the methods DPPH and ABTS respectively, revealing high antioxidant activity of the results in this period. Profit of the oil and starch of the seed was altered significantly during the development of the result of the pomegranate. There was addition of 11,57 % in the profit of oil of the 60 for 100 days after the antese, in against departure a decrease took place in the starch profit having the least profit in the results gathered to 100 days (12,97 %). Before the obtained results it is noticed that the results gathered to 90 days joined the biggest number of quality characteristics, which boards made possible to identify the age in which the results are suitable to be gathered, in the conditions of cultivation of the Meadows of Sousa, PB.
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Izquierdo-Useros, Nuria. "Maturation of Dendritic Cells & HIV Transmission to CD4(+) T cells." Doctoral thesis, Universitat Autònoma de Barcelona, 2009. http://hdl.handle.net/10803/3822.

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Las células dendríticas (DCs) están especializadas en la presentación de antígeno. Sin embargo, las DCs expuestas al virus de la inmunodeficiencia humana (VIH) también son capaces de transmitir una potente infección citopática a los linfocitos T CD4+, un proceso que frecuentemente se ha relacionado con la capacidad que tiene el receptor DC-SIGN (Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin) para unirse de forma específica a la glicoproteína de la envuelta viral. <br/>La maduración de las DCs puede aumentar la eficiencia de transmisión del VIH a los linfocitos T CD4+ a través de la trans-infección. Nuestro objetivo en este trabajo ha sido comparar el efecto de la maduración en las células dendríticas derivadas de monocitos (MDDCs) y en las células dendríticas mieloides derivadas de sangre durante el proceso de captura del VIH. Para analizar la captura y transmisión viral a las células diana competentes in vitro de un VIH pseudotipado con envuelta y el virus homólogo replicativo utilizamos las técnicas de detección de p24gag, actividad luciferasa y microscopía electrónica y confocal. Así, observamos que la maduración de las MDDCs o las DCs mieloides aumenta la captura activa del VIH de una forma independiente del receptor DC-SIGN o de la glicoproteína de la envuelta viral, incrementándose también el tiempo de retención del virus capturado. Además, verificamos que la mayor transmisión viral de las DCs maduras (mDCs) a los linfocitos T CD4+ es altamente dependiente de una captura viral activa, un proceso endocítico mediado a través de dominios de membrana enriquecidos en colesterol. Notablemente, mientras que las mDCs concentran el virus capturado en una única vesícula positiva para las tetraspaninas CD63 y CD81, las DCs inmaduras carecen de dichas estructuras, lo que sugiere un proceso de tráfico intracelular viral diferencial en cada tipo celular.<br/>Los exosomas son vesículas celulares secretadas que pueden ser internalizadas por las DCs, contribuyendo a la activación específica de antígeno de los linfocitos naive T CD4+. En esta tesis demostramos que el VIH puede explotar esta ruta intrínseca a las mDCs que permite la diseminación de antígenos a través de los exosomas, permitiendo así la trans-infección de los linfocitos T CD4+. Tras la maduración de las DCs, la captura del VIH-1, las partículas pseudovirales VIH-1 Gag-eGFP (VLPs) y los exosomas aumenta significativamente, acumulándose dentro de un compartimento CD81+. La captura de estas partículas se inhibió preincubando las mDCs con las VLPs o los exosomas, lo que sugiere que la expresión de determinantes moleculares comunes en la superficie de las VLPs y los exosomas es necesaria para la internalización mediada por las mDCs. Así mismo, la captura mediada por las mDCs es insensible a un tratamiento proteolítico, pero puede bloquearse cuando los virus, las VLPs o los exosomas se producen en células tratadas con inhibidores de la biosíntesis de los esfingolípidos, que alteran la composición lipídica de las partículas que emergen.<br/>Por último, las VLPs y los exosomas capturados por las mDCs se transmiten a los linfocitos T CD4+ de una forma independiente de la glicoproteína de la envuelta viral, resaltando la existencia de una nueva ruta de diseminación viral.<br/>En general, estas observaciones ayudan a explicar la mayor capacidad de las mDCs para transmitir el VIH a los linfocitos T CD4+, un proceso que potencialmente puede contribuir a la diseminación viral en los nódulos linfáticos in vivo, donde la replicación viral tiene lugar de forma mayoritaria y hay una interacción continua entre las células T CD4+ susceptibles y las mDCs.<br>Dendritic cells (DCs) are specialized antigen-presenting cells. However, DCs exposed to human immunodeficiency virus (HIV) are also able to transmit a vigorous cytopathic infection to CD4+ T lymphocytes, a process that has been frequently related to the ability of DC-SIGN (Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin) to bind HIV-1 envelope glycoproteins. Maturation of DCs can increase the efficiency of HIV transmission through trans-infection. We aimed to comparatively study the effect of maturation in monocyte derived dendritic cells (MDDCs) and blood-derived myeloid DCs during HIV capture process. In vitro capture and transmission of envelope pseudotyped HIV-1 and its homologous replication competent virus to susceptible target cells was assessed by p24gag detection, luciferase activity, and both confocal and electron microscopy. Maturation of MDDCs or myeloid DCs enhanced active capture of HIV in a DC-SIGN and viral envelope glycoprotein independent manner, increasing the lifespan of trapped virus. Moreover, higher viral transmission of mature DCs (mDCs) to CD4+ T lymphocytes was highly dependent on active viral capture, a process mediated through cholesterol-enriched domains. Mature DCs concentrated captured virus in a single large vesicle staining for CD81 and CD63 tetraspanins, while immature DCs lacked these structures, suggesting different intracellular trafficking processes. <br/>Exosomes are secreted cellular vesicles that can be internalized by DCs contributing to antigen specific naive CD4+ T lymphocyte activation. Here, we demonstrate that HIV can exploit this exosome antigen-dissemination pathway intrinsic to mDCs for mediating trans-infection of CD4+ T lymphocytes. Capture of HIV-1, HIV-1 Gag-eGFP viral like particles (VLPs) and exosomes by DCs was upregulated upon maturation, resulting in localization within a CD81+ compartment. Uptake of VLPs or exosomes could be inhibited by a challenge with either particle, suggesting that the expression of common determinant(s) on VLP or exosome surface is necessary for internalization by mDCs. Capture by mDCs was insensitive to proteolysis, but blocked when virus, VLPs, or exosomes were produced from cells treated with sphingolipid biosynthesis inhibitors that modulate the lipid composition of the budding particles. Finally, VLPs and exosomes captured by mDCs were transmitted to CD4+ T lymphocytes in an envelope glycoprotein-independent manner, underscoring a new potential viral dissemination pathway.<br/>Overall, these observations help explaining the greater ability of mDCs transferring HIV to CD4+ T lymphocytes, a process that can potentially contribute to the viral dissemination at lymph nodes in vivo, where viral replication takes place and there is a continuous interaction between susceptible T-cells and mDCs.
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Ladame, Dominique. "La maturation du spermatozoide : role du plasma seminal face a l'infection : a propos d'une etude statistique retrospective et d'une etude experimentale." Université Louis Pasteur (Strasbourg) (1971-2008), 1992. http://www.theses.fr/1992STR1M023.

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Koueta, Noussithe. "Etude experimentale du controle endocrine de la maturation genitale chez la seiche sepia officinalis l. (mollusque cephalopode)." Caen, 1990. http://www.theses.fr/1990CAEN2039.

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L'etude de la maturation genitale des seiches de la baie de seine a ete realisee grace a des methodes biometriques, cytologiques, d'histologie quantitative et biochimiques. Les resultats obtenus sur l'aspect qualitatif et quantitatif des cellules germinales et des cellules folliculaires grace a ces methodes sont complementaires et permettent de preciser les periodes des differentes phases de la spermatogenese et de l'ovogenese chez les seiches des cotes normandes. Au cours de la seconde annee de vie, les multiplications intenses de cellules germinales males ont lieu en aout et debut septembre et la suite de la maturation est dominee par la spermiogenese jusqu'a la reproduction en mai-juin. Dans l'ovaire, la multiplication des cellules folliculaires (previtellogenese) s'effectue en octobre et novembre, alors que la synthese du vitellus (vitellogenese) commence en decembre et se poursuit jusqu'a la reproduction (mai-juin). L'activite atcase des gonades s'est averee correlee aux divisions intenses des cellules germinales (spermatogonies et spermatocytes) et des cellules folliculaires au cours du cycle sexuel. Ces resultats prouvent que l'atcase peut etre utilisee comme indice de l'activite chez la seiche. La mise au point de deux bioessais rapides, precis, quantifiables et complementaires (activites atcase et incorporation de thymidine tritiee) en utilisant des dissociations de cellules germinales, de cellules folliculaires et de cellules des glandes annexes femelles pendant les periodes de la gametogenese intense nous a permis de montrer l'action du facteur mitogene de la gonadotropine de la glande optique sur ces cellules. Il apparait que la glande optique controle la maturation genitale des seiches grace a sa gonadotropine dont une composante est un facteur mitogene non specifique au sexe, present dans l'hemolymphe, de nature peptidique, de poids moleculaire compris entre 4000 et 5000 da
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11

Consorti, Lorenzo. "Selected larger benthic foraminifera (LBF) from the middle and late cretaceous global community maturation cycles in two adjoining palaeobioprovinces: pyrenees and tethys." Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/403772.

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En la presente tesis se discuten los resultados de un estudio arquitectural y taxonómico sobre grandes Foraminíferos bentónicos cuya presencia caracteriza los ciclos de maturación global del Cretácico Medio y Superior. La descripción de nuevos taxones, acompañadas de consideraciones sobre su estratigrafía y distribución temporal, añade datos sobre el escenario evolutivo de los grandes Foraminíferos bentónicos que caracterizan las fases antecedentes y posteriores de la extinción ocurrida durante el limite Cenomaniense-Turoniense (CTB). La presente tesis incluye cinco artículos que presentan nuevos datos o revisan los existentes desde varias localidades (España, Italia, Irán). Se presentan nuevos datos sobre la distribución de soritoideos a lo largo de todos los ambientes carbonatados del Océano del Tethys durante el máximo del ciclo de maturación del Cretácico Medio como la revisión de Praetaberina (ex Taberina bingistani) desde sur de Italia a Irán. Este trabajo de revisión y los datos de estratigrafía isotópica muestran que la distribución del nuevo género se limita al Cenomaniense superior con dos especies; una desde la plataforma Apulica y la otra de las montañas de Zagros. El artículo sobre los soritoideos de la península Ibérica ha sido importante para definir la distribución estratigráfica de este grupo en una zona poco estudiada. Nuevos datos sobre la recuperación y la evolución de las comunidades de grandes Foraminíferos bentónicos después de la extinción del Cenomaniense-Turoniense enriquece el conocimiento sobre la dinámica del ciclo de maturación global del Cretácico Superior en las paleobioprovincias del Pirineo y del Tethys. Los nuevos rotaloideos que aquí se presentan han sido datados por medio de la estratigrafía de estroncio, indicando la existencia de dos comunidades que evolucionaron de manera separada en cada una de las bioprovincias. Sus diversificación empiezó en el Turoniense superior pero la exacta relación temporal entre ambas áreas queda sin resolver. Finalmente, la presencia de Pseudorhapydionina en el Santoniense de la paleobioprovincia del Pirineo indica que este género sobrevivió a la extinción del CTB. Hasta ahora Pseudorhapydionina habia sido considerada típica del Cenomaniense del Tethys, pero este hallazgo indica que su evolución continuó en el Pirineo después de la extinción del CTB.<br>Architectural and taxonomic study of selected larger benthic Foraminifera from the Upper Cretaceous of the Tethyan and Pyrenean paleobioprovinces is presented within a context of Middle and Late Cretaceous Global Community Maturation Cycles. Descriptions and determinations of the stratigraphic distributions of some new and revised taxa provide further data in reconstructing evolutionary trends among the larger benthic Foraminifera before and after the Cenomanian-Turonian boundary (CTB) extinction. This thesis includes five research papers presenting new data and reviewing existing knowledge from widespread localities (Spain, Italy and Iran). New perspectives are presented on soritoidean palaeobiogeography throughout the carbonate shelves and platforms of Tethyan Ocean during the peak of the Middle Cretaeous GCMC as well as a revision of Praetaberina (ex "Taberina" bingistani) from Southern Italy and Iran. The revision of Praetaberina and chemostratigraphy of the host strata show that the distribution of this genus is limited to the Upper Cenomanian where two species are described from the Apulian Platform and Zagros Mountains respectively. The report of Iberian soritoideans has been crucial in defining their stratigraphic distribution in a area that has been little studied. New data defining the recovery and the evolution of the foraminiferal communities after the Cenomanian-Turonian boundary extinction has enriched knowledge of the Late Cretaceous GCMC of the Pyrenean and Tethyan paleobioprovinces. The new rotaloideans described from these areas have been stratigraphically anchored by means of Strontium Isotope Stratigraphy indicating that two communities evolved separately in each palaeobioprovince. Diversification of these communities started at least during the late Turonian, but the exact timing remains unresolved. Finally the occurrence of the genus Pseudorhapydionina in the Santonian of the Pyerenean palaeobioprovince indicates that this genus was not affected by the Cenomanian-Turonian extinction event. Pseudorhapydionina was formerly considered to be confined to the Cenomanian within the Tethyan area but the new record presented here indicates its evolution in the Pyrenean area continued after the Cenonian-Turonian boundary event.
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Bernuzzi, Viviane LEHR PAUL. "CONTRIBUTION A L'ETUDE EXPERIMENTALE DES EFFETS D'INTOXICATIONS ALUMINIQUES PRECOCES CHEZ LE RAT : DEVELOPPEMENT PHYSIQUE, MATURATION NEURO-MOTRICE, COMPORTEMENT EN SITUATIONS D'APPRENTISSAGE /." [S.l.] : [s.n.], 1988. ftp://ftp.scd.univ-metz.fr/pub/Theses/1988/Bernuzzi.Viviane.SMZ889.pdf.

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13

Hernández, Gras Francesc. "Identificació i caracterització de proteïnes relacionades en l'acumulació de carotenoides en el fruit del tomàquet." Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/104269.

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Els carotenoids són el major grup de pigments presents en la natura. Aquests compostos són molt apreciats al presentar la capacitat de prevenir malalties cardiovasculars, certs tipus de càncer i diversos processos degeneratius. Malgrat la necessitat d’aquests compostos els humans no són capaços de sintetitzar-los y s’han adquirir en la dieta. Essent el fruit del tomàquet la major font de carotenoids en la dieta occidental. El licopè i el β-carotè són els carotenoids que es produeixen en grans quantitats en el fruit del tomàquet al llarg del procés de maduració. L’acumulació de carotenoides provoca el característic color vermell del fruit i constitueix una de les principals característiques nutricionals del tomàquet madur. L’acumulació de licopè i β-caroteno se realitza dins d’un plast específic anomenat cromoplast. Actualment l’acumulació no ha estat extensivament estudiada, tot i que s’ha postulat que es realitza en entorns membranosos i mitjançat complexes lipoproteics (Vishnevetsky, et al. 1999). El coneixement dels mecanismes i proteïnes implicats en el procés és un dels passos claus per entendre l’acumulació i la informació pot ser utilitzada pera incrementar o modificar la quantitat de licopè i β-caroteno en el fruit, objectiu molt rellevant en els programes de millora del tomàquet. En aquest treball s’ha procedit a identificar i caracteritzar gens i proteïnes relacionades amb l’acumulació de carotenoids en el fruit de tomàquet des de dues aproximacions diferents. En la primera, es va determinar quins individus dins d’una població de línies de caràcter autofecunadatiu provinents del creuament dels tomàquet Solanum lycopersicum (Cv Money Maker) i Solanum pimpinellifollium presentaven nivells contrastants de carotenoids. Una cop detectades les línies contrastants, amb alts o baixos nivells de carotenoides, es van determinar quins eren els gens amb expressió diferencial en experiments de microarray, caracteritzant els més importants. I com a segona aproximació es va procedir a purificar, mitjançant tècniques proteòmiques, complexes lipoproteics i la posterior caracterització de las proteïnes detectades en ells.<br>Los carotenoides son el mayor grupo de pigmentos presentes en la naturaleza. Estos compuestos son muy apreciados ya que presentan la capacidad de prevenir enfermedades cardiovasculares, ciertos tipos de cáncer y diversos procesos degenerativos. A pesar de la necesidad de estos compuestos los humanos no son capaces de sintetizarlos y los deben adquirir por la dieta. Siendo el fruto de tomate la mayor fuente de carotenoides en la dieta occidental. El licopeno y β-caroteno son los carotenoides que se producen en mayores cantidades en el fruto del tomate durante el proceso de maduración. La acumulación de dichos compuestos provoca el característico color rojo del fruto y constituye una de las principales características nutricionales del tomate maduro. La acumulación de licopeno y β-caroteno se realiza dentro de un plasto específico llamado cromoplasto. Actualmente la acumulación no ha sido extensivamente estudiada, aunque se ha postulado que se realiza en entornos membranosos y mediante complejos lipoproteicos (Vishnevetsky et al. 1999). El conocimiento de los mecanismos y proteínas implicados en el proceso es unos de los pasos claves para entender la acumulación y la información puede ser usada para incrementar o modificar la cantidad de licopeno y β-caroteno en el fruto, objetivo muy relevante en los programas de mejora del tomate. En este trabajo se ha procedido a identificar y caracterizar genes y proteínas relacionadas con la acumulación de carotenoides en el fruto de tomate desde dos aproximaciones diferentes. En la primera aproximación, se determino que individuos en una población de líneas de carácter autofecunadativo provinentes del cruce de Solanum lycopersicum (Cv Money Maker) y Solanum pimpinellifollium presentaban niveles contrastantes de carotenoides. Una vez detectadas las líneas contrastantes, con altos o bajos niveles de carotenoides, se determinaron cuales eran los genes de expresión diferencial mediante experimentos de microarray, llegando a caracterizar las más importantes. Y Como segunda aproximación se procedió a purificar, mediante técnicas proteómicas, complejos lipoprotéicos i la posterior caracterización de las proteínas detectadas en los mismos.
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Dong, Guangqiang. "Modelling and Experimental Results on Stochastic Model Reduction, Protein Maturation, Macromolecular Crowding, and Time-varying Gene Expression." Thesis, 2009. http://hdl.handle.net/1807/19264.

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Gene expression, which connects genomic information to functional units in living cells, has received substantial attention since the completion of The Human Genome Project. Quantitative characterization of gene expression will provide valuable information for understanding the behavior of living cells, and possibilities of building synthetic gene circuits to control or modify the behavior of naturally occurring cells. Many aspects of quantitative gene expression have been studied, including gene expression dynamics and noise in E. coli. The gene expression process itself is stochastic, and modelling approaches have been broadly used to study gene expression noise; however, stochastic gene expression models are usually large and time intensive to simulate. To speed up simulations, we have developed a systematic method to simplify gene expression models with fast and slow dynamics, and investigated when we can ignore the gene expression from the background genome when modelling the gene expression from plasmids. When modelling the noise in gene expression, one usually neglected aspect is the slow maturation process of fluorescent proteins, necessary for the protein to give out fluorescence after it is produced. By modelling, we show that the maturation steps can bring large changes to both the mean protein number and the noise in the model. An unstudied aspect of gene expression dynamics is the time dependent gene expression behavior in E. coli batch culture. Contrary to the usual assumption, we have found, in E. coli batch culture gene expression, that there is no steady state in terms of both the mean number of proteins and the noise. Negative feedback is thought to be able to reduce the noise in a system, and experiments have shown that negative feedback indeed suppresses the noise in gene expression, but the modelling shows that negative feedback will increase the noise. We have found that the increase of noise by feedback is due to the exclusion of extrinsic noise from the model, and that negative feedback will suppress the extrinsic noise while increasing the intrinsic noise. Living cells are crowded with macromolecules, which will, predicted by modelling, make the reaction constant time dependent. Our experimental observation has confirmed this prediction.
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Kremer, David [Verfasser]. "p57kip2 is dynamically regulated in experimental autoimmune encephalomyelitis and acts as a negative regulator of oligodendroglial maturation / vorgelegt von David Kremer." 2009. http://d-nb.info/999995952/34.

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Listopad, Joanna Jadwiga [Verfasser]. "HO-1 induction by Co-PPIX suppresses experimental skin inflammation, T cell immunity and dendritic cell maturation and function / von Joanna Jadwiga Listopad." 2006. http://d-nb.info/983977887/34.

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Mißbach, Helge. "Formation and preservation of abiotic organic signatures vs. lipid biomarkers—experimental studies in preparation for the ExoMars 2020 mission." Thesis, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E42A-7.

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