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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.
71

Etude transgénérationelle des altérations de l'ADN et de leurs conséquences sur les traits d'histoire de vie et le budget énergétique de Daphnia magna exposé à l'uranium appauvri. / Transgenerational study of DNA alterations and their consequences on life history traits and energy budget of Daphnia magna exposed to depleted uranium

Plaire, Delphine 12 December 2013 (has links)
Ce travail a pour objectif d’explorer les altérations de l’ADN et leurs conséquences potentielles pour les traits d’histoire de vie (survie, croissance et reproduction) d’un invertébré aquatique, Daphnia magna exposé à l’uranium appauvri. La démarche expérimentale vise à évaluer l’accumulation et la transmission des altérations de l’ADN suite à une exposition sur deux générations successives (F0 et F1). Différents scénarios d’exposition mis en place pour tester la sensibilité spécifique de divers stades de vie. Lors d’expositions continue et post-éclosion, les résultats mettent en évidence une accumulation et une transmission des dommages à l’ADN au fil des générations en parallèle de la sévérité des effets. Les altérations de l’ADN sont reportées dès l’éclosion de F1 dès 2 µg.L 1. Les effets sur la croissance et la reproduction sont plus sévères lorsque le stade embryonnaire est exposé et restent visibles dès 9,9 µg.L-1 malgré un retour en milieu non contaminé à l’éclosion. Les résultats suggèrent que les dommages à l’ADN pourraient être des indicateurs précoces de futurs effets sur les traits d’histoire de vie. Une analyse mécanistique des résultats expérimentaux est conduite à l’aide du modèle DEBtox afin de mieux cerner les causes de l’aggravation des effets au cours des générations. Un modèle à deux facteurs de stress (l’un corrélé à la concentration d’exposition et l’autre à un niveau de dommages) est développé. Les ajustements suggèrent l’implication d’un second mode d’action (une augmentation des coûts de croissance et de maturation) pour expliquer les effets immédiats de l’uranium sur la nutrition et les conséquences des dommages accumulés au fil des générations. / This PhD work explored how depleted uranium alters DNA and affects life history traits (survival, growth and reproduction) of an aquatic invertebrate, Daphnia magna. An experimental study is performed to evaluate DNA accumulation and transmission during an uranium exposure over two successive generations (F0 and F1). Different exposures scenarios are achieved to test the specific sensitivity of several life stages to uranium. Genotoxic effects are estimated using random amplified DNA technique combined with PCR. In continuous and post-hatching exposure scenarios, results highlighted an accumulation and a transmission of DNA damage across generations with an increase in effect severity. DNA alterations are reported at hatching of F1 at 2 µg L-1. Effects on growth and reproduction are stronger when the embryo stage is exposed and remain visible at 9.9 µg L-1 despite a return in a clean medium at hatching. Results suggest that DNA damage could be used as early indicators of future effects on life history traits. A mechanistic analysis of experimental results is conducted using a DEBtox model to better understand the causes of the increase in effect severity across generations. A model with two stress factors (one correlated to external concentration and another correlated to a damage level) is developed. Results of fits suggest the involvement of one second mode of action (increase in costs for growth and maturation) to explain immediate effects of uranium on nutrition and consequences of cumulated damage across generations.
72

Approche moléculaire et mécaniste de la réponse transgénérationnelle lors d'une irradiation gamma chronique chez le cladocère Daphnia magna / Molecular and mechanistic studies of the transgenerational response during a chronic gamma irradiation in the cladoceran Daphnia magna

Trijau, Marie 18 December 2018 (has links)
Afin de protéger durablement les écosystèmes face aux rejets planifiés ou accidentels de radionucléides dans l’environnement, il est essentiel d’évaluer l’impact de l’exposition des organismes aux radiations ionisantes sur le long terme, à l’échelle de plusieurs générations. Dans ce contexte, ce travail de doctorat vise à améliorer la caractérisation des processus moléculaires et la prédiction des effets transgénérationnels lors d’une exposition aux radiations gamma. Une approche expérimentale concerne l’étude des modifications épigénétiques radio-induites, c’est-à-dire des modifications des mécanismes régulant l’activité des gènes sans modification de la séquence d’ADN elle-même et de leur transmission au fil des générations. Cette étude a permis de mettre en évidence que certaines modifications de la méthylation de l’ADN, l’un des mécanismes épigénétiques les plus étudiés, peuvent être transmises par la lignée germinale aux les générations non-exposées (génération F3) suite à une exposition parentale (génération F0) externe aux radiations gamma (6,5 µGy.h-1 et 41,3 mGy.h-1) pendant 25 jours. Dans une seconde approche, un modèle mécaniste DEBtox (Budget Energétique Dynamique appliqué à la toxicologie) est modifié pour permettre l’analyse des effets des radiations gamma sur la croissance et la reproduction de D. magna à l’échelle de plusieurs générations. Pour ce faire, on utilise des compartiments de dommage, dont le niveau peut être hérité d’une génération à la suivante. Le modèle est ajusté aux données avec des méthodes d’inférence bayésienne afin d’estimer les paramètres tout en tenant compte des incertitudes qui leur sont associées. / In order to durably protect ecosystems facing planned or accidental releases of radionuclides, the long-term impact of organism exposure to ionizing radiation must be studied on a multigenerational scale. The aim of this PhD is to improve the characterization of molecular processes and the prediction of transgenerational effects during a gamma irradiation. First, an experimental approach investigated on radio-induced modifications of epigenetic processes, i.e. changes in mechanisms that regulate gene expression without changing DNA sequence itself and on the transmission of these modifications to subsequent generations. Significant changes in DNA methylation, a well-studied epigenetic mechanism, detected in generation F3 clearly showed that epigenetic modifications could be transmitted to unexposed generations, in response to the exposure of a parental generation (F0) to external gamma radiation (6.5 µGy.h-1 et 41.3 mGy.h-1) for 25 days. Second, a mechanistic modelling approach used a modified version of the DEBtox model (Dynamic Energy Budget model applied to toxicology) in order to analyze effects of gamma radiation on D. magna growth and reproduction over several generations. To that end, damage compartments, with damage levels that were transmitted from one generation to the next, were included. The model was fitted to data using Bayesian inference methods, in order to estimate the parameters while considering their associated uncertainty.
73

Affect recognition and emotional availability in mother-child interaction

Kluczniok, Dorothea 08 July 2016 (has links)
Ausgangspunkt der vorliegenden Arbeit ist die gut belegte Assoziation zwischen mütterlicher Depression und ungünstigen emotionalen und behavioralen Folgen für ihre Kinder. Allerdings sind die Faktoren, die zu der transgenerationalen Übertragung der Depression beitragen, noch nicht geklärt. Ziel dieser Arbeit ist es, zwei möglicherweise dazu beitragende psychologische Faktoren zu untersuchen: (1) Affekterkennung von Gesichtsausdrücken in Mutter-Kind Dyaden und (2) mütterliche emotionale Verfügbarkeit. Dazu wurden drei Studien durchgeführt. Studie I untersucht mittels funktioneller Magnetresonanztomographie (fMRT) unterscheidbare und überlappende Aktivierungsmuster bei gesunden Müttern, während sie fröhliche und traurige Gesichter ihres eigenen Kindes sehen. Studie II verwendet eine Morphing-Aufgabe, um die Affekterkennung in Müttern mit remittierter Depression und ihren Kindern zu untersuchen. In Studie III wird die emotionale Verfügbarkeit von Müttern mit remittierter Depression in einer Verhaltensbeobachtung untersucht. Ergebnisse der Studie I zeigen eine größere Gehirnaktivierung der Mütter bei traurigen eigenen Kindergesichtern in der Amygdala und anterioren Cingulum, hingegen bei fröhlichen im Hippocampus und inferioren Frontalgyrus. Überlappende Aktivierung wurde in der Insula gefunden. Diese Aktivierungsmuster könnten feinfühliges mütterliches Verhalten erleichtern und das Aufrechterhalten der Mutter-Kind Beziehung unterstützen. Ergebnisse von Studie II belegen einen negativen Verarbeitungsbias bei Müttern mit einer remittierten Depression, wobei parallele Veränderungen bei ihren Kindern gefunden wurden. Dies könnte auf einen transgenerationalen Übertragungsprozess hinweisen. Ergebnisse von Studie III zeigen eine verminderte emotionale Verfügbarkeit bei Müttern in Remission, was eine Trait-Eigenschaft darstellen könnte. / Starting point of the present dissertation is the well-established association between maternal depression and adverse emotional and behavioral outcomes in children. The factors contributing to the transgenerational transmission of depression have not been fully elucidated. The aim of this thesis is to investigate two psychological factors that potentially contribute to this transgenerational association: (1) affect recognition of facial expressions in mother-child dyads and (2) maternal emotional availability. Therefore, three studies have been conducted. In study I, functional magnetic resonance imaging (fMRI) is used to measure dissociable and overlapping brain activation in healthy mothers, while they view happy, neutral and sad faces of their own child. By using a morphing task, study II tests the hypothesis that affect recognition is biased in mothers with depression in remission and their children. Study III investigates whether emotional availability is reduced in mothers remitted from depression. Study I revealed greater brain activation in the amygdala and anterior cingulate cortex while mothers viewed sad faces of their own child, whereas greater brain activation was detected in the hippocampus and inferior frontal gyrus in response to happy faces. Conjoint activation was found in the insula. These activations might facilitate sensitive maternal behavior and promote mothers to maintain the mother-child relationship. Findings of study II demonstrate a negative processing bias in mothers with depression in remission, which was paralleled in their children. This finding could possibly point to a process of transgenerational transmission. Results of study III indicate reduced emotional availability in mothers who have remitted from depression, which might represent a trait characteristic of depression.
74

Integrated approach of anatomical, physiological and biochemical parameters for the study of tolerance mechanisms to cadmium in tomato accessions / Abordagem integrada de parâmetros anatômicos, fisiológicos e bioquímicos para o estudo de mecanismos de tolerância ao cádmio em acessos de tomateiro

Carvalho, Marcia Eugenia Amaral de 05 July 2017 (has links)
Tomato (Solanum lycopersicum L.) consumption has increased every year due to the fruit attractiveness, several utilizations, and beneficial effects for human health. However, tomato fruits can accumulate a Cd concentration that exceeds the safety threshold for human consumption of vegetables, even when plants are grown in soil with acceptable Cd level. Cd is a non-essential, hazardous element to biological systems, triggering several diseases in humans. In plants, Cd disturbs the antioxidant machinery, changes the nutritional status, and impairs the photoassimilate production and/or partitioning, hence reducing fruit yield and quality. However, distinct tomato accessions can present contrasting tolerance degree to Cd toxicity, as detected by our group in previous studies. The use of these accessions is a powerful approach to identify strategies employed by plants to cope with Cdinduced challenges, and the acknowledgement of such strategies can be potentially used in breeding and biotechnological programs to improve fruit yield and quality in crops that were cultivated in contaminated fields. The set of studies that compose the present thesis aimed (i) to identify the main mechanisms for the contrasting tolerance degree to Cd-induced toxicity in tomato accessions after short and long-term Cd exposure; (ii) to evaluate the relationship among tolerance degree and fruits attributes in plants that were grown in Cd-containing soil, and (iii) to determine the transgenerational effects of Cd-induced stress. In the first experiment, nine tomato accessions with a varied tolerance degree, which was based on biomass accumulation, to Cd exposure were grown in hydroponic solution containing CdCl2 35 μM for 6 days. Avoidance of high Mg concentration in roots was identified as a plant strategy to mitigate Cd toxicity by preventing formation of root hairs. Regarding the mode of action of Cd toxicity, Mn excess in leaves, in addition to the high Cd concentration per se, seems to be coupled to leaf damages that are enhanced by the increased Zn and B concentrations in the photosynthetic tissues. In the second experiment, tolerant (Yoshimatsu) and sensitive (Tropic Two Orders) genotypes were grown in Cd-containing soil, in order to evaluated production parameters. After plant exposure to Cd, the tolerant genotype presented an increased fruit diameter, height and weight, when compared to the control plants. In both cultivars, Cd concentration varied according to the following descending order: roots = leaf blade > (floral receptacle, peduncle and sepals) > stem = fruit peel = fruit pulp. Moreover, data suggested that floral receptacle and its related-structures acted as a barrier to the Cd transportation to the fruits, but it was not enough to avoid Cd reaching the fruits. Furthermore, Cd exposure provoked remarkable reductions in the Mg concentration in roots of sensitive and tolerant genotypes, revealing that both tomato cultivars are able to employ this mechanism for plant acclimation to long-term Cd exposure. Considering such information, it is possible that, under the short-term Cd exposure, tolerant accessions activate this mechanism either early or faster than sensitive genotypes. In addition, positive transgenerational effects on seed germination and vigor of the tolerant genotype were triggered by the plant-mother cultivation in Cd-containing media, despite of the increased chromosomal abnormality. This work reported new insights about the effects of Cd exposure on tomato development, tolerance mechanisms, fruit quality and yield of tomato, as well as Cd distribution in the plants. / O consumo de tomate (Solanum lycopersicum L.) tem aumentado a cada ano devido a atratividade dos frutos, suas diversas utilizações e efeitos benéficos para a saúde humana. No entanto, os frutos de tomate podem acumular uma concentração de cádmio (Cd) que excede o limiar de segurança para o consumo humano, mesmo quando as plantas são cultivadas em solo com níveis aceitáveis de Cd. Cádmio e um elemento não-essencial, extremamente perigoso para os sistemas biológicos, desencadeando varias doenças em seres humanos. Nas plantas, o Cd perturba a maquinaria antioxidante, altera o estado nutricional e prejudica a produção e /ou o particionamento de fotoassimilados, frequentemente reduzindo a produtividade e qualidade de frutos. No entanto, diferentes acessos de tomateiros podem apresentar contrastantes graus de tolerância a toxicidade gerada pela exposição ao Cd, como detectado em estudos anteriores de nosso grupo. O uso desses acessos e uma abordagem poderosa para identificar as estratégias empregadas pelas plantas para lidar com os desafios induzidos pelo Cd; e o conhecimento de tais estratégias pode ser potencialmente utilizado em programas biotecnológicos e de melhoramento genético. Deste modo, o conjunto de estudos que compõem a presente tese objetivou (i) identificar os principais mecanismos que suportam o grau de tolerância contrastante a toxicidade induzida por Cd em acessos de tomate após exposição a curto e longo prazos a este metal pesado; (ii) avaliar a relação entre o grau de tolerância e os atributos físico-químico de frutos oriundos de tomateiros cultivados em solo contendo Cd, e (iii) determinar os efeitos transgeracionais do estresse induzido por Cd. No primeiro experimento, nove acessos de tomateiro com graus variados de tolerância a exposição ao Cd, baseado na acumulação de biomassa, foram cultivados em solução hidropônica contendo 35 μM de CdCl2 durante 6 dias. O impedimento de elevada concentração de magnésio (Mg) em raízes foi identificado como possível estratégia da planta para mitigar a toxicidade de Cd, por meio da evitação da formação de pelos radiculares. Em relação ao modo de ação da toxicidade induzida por Cd, o excesso de Mn, em adição a elevada concentração de Cd, parece estar acoplado aos danos foliares que são acentuados ainda mais pelas altas concentrações de zinco (Zn) e boro (B) nos tecidos fotossintéticos de plantas sob exposição ao Cd. No segundo experimento, os genótipos tolerantes (Yoshimatsu) e sensíveis (Tropic Two Orders) foram cultivados em solo contendo Cd, a fim de avaliar os parâmetros de produção. O genótipo tolerante apresentou frutos com maior diâmetro, altura e peso após o cultivo em solo contendo Cd, quando comparado as plantas controle. Em ambas as cultivares, a concentração de Cd variou de acordo com a seguinte ordem descendente: raízes = folíolos> (receptáculo floral, pedúnculo e sépalas) > caule = casca de fruta = polpa de fruta. Alem disso, dados sugerem que o receptáculo floral e suas estruturas atuaram como uma barreira ao transporte de Cd para os frutos, entretanto, ela não foi suficiente para evitar que o Cd atingisse os frutos. Em adição, a exposição ao Cd provocou notáveis reduções na concentração de Mg nas raízes de genótipos sensíveis e tolerantes, revelando que a aclimatação das plantas depende do baixo status de Mg em tecidos radiculares. Desde que ambas as cultivares são capazes de empregar este mecanismo, os dados sugerem que, durante a exposição a curto prazo ao Cd, acessos tolerantes são capazes de ativa-lo ou mais cedo ou mais rápido do que acessos sensíveis. Ademais, efeitos transgeracionais positivos na germinação e vigor das sementes do genótipo tolerante foram desencadeados pelo cultivo planta-mãe em solo com Cd, apesar do aumento de anormalidades cromossômicas. Este trabalho reportou novos conhecimentos sobre os efeitos da exposição ao Cd sobre o desenvolvimento do tomateiro, mecanismos de tolerância, qualidade e rendimento de frutos, bem como a distribuição de Cd dentro da planta.
75

Ecologie évolutive du priming immunitaire chez le ténébrion meunier, Tenebrio molitor / Evolutionary ecology of immune priming in the mealworm beetle, Tenebrio molitor

Dhinaut, Julien 06 December 2017 (has links)
Il est maintenant connu que de nombreux invertébrés peuvent moduler leur réponse immunitaire en fonction de leur expérience immunologique. Ce phénomène est appelé priming immunitaire. Si les mécanismes du priming immunitaire restent encore assez méconnus, il a pour conséquence d’apporter un bénéfice aux individus lors d’une seconde rencontre avec un agent pathogène, via une élévation de leur immunocompétence. Une caractéristique assez étonnante du priming immunitaire est qu’il peut se manifester chez la descendance. Ce transfert trans-générationnel d’immunité (TTGI), ainsi que le priming immunitaire, doivent avoir évolués à la suite de challenges répétitifs par les mêmes agents pathogènes durant la vie des individus et au fil des générations. Ainsi, le priming et le TTGI doivent être plus efficaces et moins coûteux vis à vis des parasites exposant l’hôte à la plus grande probabilité de réinfection. De plus, il est maintenant prouvé que la réponse immunitaire chez les insectes est génétiquement variable. Pour comprendre l’évolution du TTGI et de son potentiel de réponse à la sélection, il convient d’étudier la composante génétique de sa variabilité. Au cours de cette thèse, j’ai associé l’expression du priming et du TTGI chez un insecte à un type de bactéries, qui a du agir comme la principale pression de sélection sur le système immunitaire de cette espèce hôte. Cela s’est fait via l’identification de différents coûts et bénéfices, qui ont également mis en exergue certains mécanismes possibles dans la réalisation de ces phénomènes immunitaires. Pour ce faire, j’ai utilisé comme organisme modèle le ténébrion meunier, Tenebrio molitor.Dans le premier chapitre, nous avons étudié la survie d’individus adultes de T. molitor face à une infection bactérienne, en fonction de leur propre expérience immunitaire ou de celle de leur mère. Nous avons constaté que le priming et le TTGI étaient plus efficaces et moins coûteux vis à vis des bactéries à Gram-positif. Cetté étude a également révélé que, contrairement à ce que de précédentes recherches suggérent, les hémocytes ne jouent pas nécessairement un rôle majeur dans le priming immunitaire et le TTGI.Dans le deuxième chapitre, nous avons stimulé le système immunitaire de femelles adultes de T. molitor avec deux bactéries Gram-positives. Nous avons mis en évidence que la protection transmise aux oeufs pouvait résulter d’un transfert maternel de peptides antibactérien, ou que ces peptides pouvaient être produits par l’œuf lui-même, en fonction de la bactérie utilisé pour stimuler la mère. Il s’avère que quel que soit le mécanisme, le TTGI améliore le taux d’éclosion des œufs et peut même s’accompagner d’un bénéfice en survie pour les jeunes larves.Dans le troisième chapitre, nous avons stimulé le système immunitaire de femelles de lignées consanguines afin de quantifier la variation génétique de l'investissement maternel à la protection des œufs et mesuré d’autres traits associés à la valeur sélective des mères et de la descendance. Malheureusement, du fait d’un nombre trop faible de lignées et d’individus utilisés au sein de nos lignées, il nous a été impossible de conclure quant à l’existence de bases génétiques associées au TTGI.Dans le quatrième chapitre, nous avons passé en revue l’ensemble des études concernant le TTGI. Cela nous a permis de mettre en exergue les principales caractéristiques et les mécanismes identifiés, en fonction de l’écologie et de l’évolution du phénomène.Les bénéfices et les coûts associés au priming ainsi qu’au TTGI suggèrent que les bactéries à Gram-positif ont été la principale pression de sélection ayant contraint l’évolution du système immunitaire de T. molitor. En ce qui concerne le TTGI, de plus amples recherches sont nécessaires afin de trancher quant à l’existence de bases génétiques associées au phénomène. / Many organisms can improve their immune response as a function of their immunological experience, a phenomenon called immune priming. While the mechanisms through which immune priming is achieved remain unknown, individuals that survived to a given parasite are better protected against subsequent exposures. This immune priming can cross generations (trans-generational immune priming – TGIP), preparing offspring for prevailing parasite environment. Both individual and trans-generational immune priming might be adaptive and may have evolved from repeated challenges by the same pathogens during the host lifetime or across generation. While protection could be cross-reactive, a certain level of specificity may exist in response to the range of pathogens from which immue priming may have evolved. Thus, immune priming and TGIP should be more efficient and less costly with respect to pathogens exposing the host to the greatest probability of re-infection. Moreover, it is now known that insect immune response is genetically variable. To understand the evolution of TGIP and its impact on life history evolution, we need to explore its quantitative genetics. During my thesis, I found that the expression of individual immune priming and TGIP in the mealworm beetle, Tenebrio molitor, is dependent of a range of pathogens that might have been a major selective pressure on the immune system of this insect species. This was done through the characterisation of costs and benefits of the expression of immune priming in response to challenges with a large range of bacterial pathogens. This work also highlighted potential mechanisms through which these immune phenomena could be achieved.In a first chapter of this thesis, we examined the survival of individuals to infection with different bacteria according to their own immunological experience or that of their mother with these bacteria. We found that priming response to Gram-positive bacteria was particularly more efficient and less costly than priming response to Gram-negative bacteria. This study also shows that, contrary to what is currently believed, the cellular component of the T. molitor immune system does not necessarly play a major role in providing immune protection through individual immune priming or TGIP.In a second chapter, we have stimulated the immune system of adult females with two Gram-positive bacteria to study maternal transfer of immunity to the eggs. We found that the process throght which eggs are protected is dependent on the bacterial pathogen used to immune challenge the mother. Indeed, depending of the bacterial pathogen that immune challenged the mother, antibacterial activity in the eggs are either transfeered by the mother or produced by the egg itself, Furthermore, whatever the mechanism through which egg protection was achieved, primed eggs exhibited enhanced hatching rate and the resulting larvae even showed improved early survival to food privation.In a third chapter, we used inbred lines of T. molitor to study the quantitative genetics of TGIP. The aim of this work was to test whether TGIP could be heritable and whether its expression is genetically associated to other fintness traits of mothers and offspring. Unfortunately, due to a low number of inbred lines available and a low number of samples within some of these lines, it was impossible to conclude about the genetic basis associated to TGIP.In a fourth chapter, we produced a review on TGIP. This allowed us to highlight the main characteristics and mechanisms curently identified, and the ecology and the evolution of the phenomenon.Costs and benefits associated to immune priming and TGIP suggest that Gram-positive bacteria might have been a major selective pressure at the origin of these phenomena in T. molitor. Whether TGIP has genetic basis still required further research.
76

Dieta hiperlipídica materna: influências sobre o comportamento maternal e o desenvolvimento da prole. / Maternal high fat diet: influences on maternal behavior and offspring development.

Klein, Marianne Orlandini 22 July 2016 (has links)
Uma nutrição maternal rica em lipídios pode causar prejuízos no desenvolvimento e na vida adulta dos descendentes, como elevado risco de desenvolver alterações metabólicas e obesidade, e também parece alterar a sinalização central por opióides. Porém, estudos realizados a fim de investigar a influência da dieta hiperlipídica (HF) materna sobre o comportamento materno e o desenvolvimento da prole não são conclusivos. Este trabalho investigou a influência da dieta HF sobre a interação mãe-filhote, em duas gerações, e os efeitos imediatos e tardios sobre a prole, relacionando-os ao sistema opióide. As mães HF apresentaram prejuízos na ejeção do leite e maior expressão dos receptores opióides no hipotálamo. No geral, os descendentes HF apresentaram elevados níveis de colesterol, baixa leptina plasmática, maior expressão de peptídeos relacionados à ingestão alimentar, e menor peso. Portanto, o consumo materno de dieta HF causou alterações metabólicas, comportamentais e na expressão gênica na mãe e nos descendentes, mesmo que esses animais não tenham se tornado obesos. / A maternal nutrition high in fat may impair offspring development and adulthood, increasing the risk to develop metabolic alterations and obesity, and may modify the opioids central signaling. However, studies investigating maternal high fat (HF) diet influences on maternal behavior and offspring development are inconclusive. This study aimed to evaluate the influences of a diet high in fat on mother-pup interaction, in two generations, and its early and late effects in the offspring, connecting them to the opioid system. HF dams show decreased milk ejections and higher expression of opioid receptors in the hypothalamus. Overall, HF offspring had higher cholesterol levels, less serum leptin, higher expression of peptides related to food intake, and were lighter. Therefore, maternal intake of HF diet promoted metabolic, behavioral and gene expression alterations in the mother and her offspring, even though these animals did not become obese.
77

La quête identitaire des AICS en intrafamilial : l'influence de l'environnement sur le fait psychique individuel / The identity quest of Authors of Sexual Character's Infringement within familial : the influence of the environment on the individual psychic's acting

Debarbieux, Audrey 15 May 2018 (has links)
Derrière tout acte il y a une sorte de « mise en scène », une « tentative d'exprimer » ce que l'auteur ne parvient à mettre en mots, à métaboliser, d'où le recours au primat de l'agir. Dans ce travail auprès d’Auteurs d’Infraction à Caractère Sexuel en intrafamilial, il est question de saisir, d'appréhender les conditions du passage à l'acte et ce que celles-ci ont pu engendrer au sein du psychisme du sujet, pour favoriser la transgression.À travers diverses notions tirées de la littérature analytique, notamment celles attenantes à la construction psychique, à la clinique du traumatisme ou encore de la transgénérationnalité, est mise en débat la question de l'influence de l’environnement sur le fait psychique individuel.Posant, de ce fait, l'hypothèse que les identifications et répétitions transgénérationnelles d’origines traumatiques peuvent être en jeu dans le passage à l'acte, en particulier chez les AICS en intrafamilial. Ce type de passage à l'acte pourrait-il alors représenter une résolution d'une dynamique familiale vécue comme « défaillante », voire traumatique, pour le sujet ? Dans une approche phénoménologique associée à une posture psychanalytique, sont déclinés sept accompagnements de patients nous permettant de répondre à ces interrogations. L'objectif étant de réaliser une étude clinique basée sur le vécu subjectif de chacun d’entre eux, afin de mettre en lumière ce qui pourrait faire défaut dans leur structuration, leurs investissements et rapports objectaux.Le voyage au travers des cas proposés permet de poser la question du caractère résolutif de ces passage à l’acte vis-à-vis d’une dynamique familiale, dans laquelle s’origine un vécu traumatique ? Par l’infraction sexuelle, perpétrée en intrafamilial, le sujet passe-t-il par le corps et l’objectalisation d’un autre familial pour crier sa souffrance, son « mal à être » ? Le passage à l’acte, chez ces Auteurs d’Infractions à Caractère Sexuel en intra-familial, est il résolutif d’une problématique identitaire traumatique, venant d’une nécessité de trouver un sens, une recherche de signifiance à l’existence même du sujet ? Via l'analyse des mécanismes de défenses, des représentations, ainsi que des positions transférentielles et contre-transférentielles mises en jeu, il s’agit de travailler la remise en sens, pour permettre à ces patients de développer leurs capacités d’élaboration, leur redonner une place, dans le respect de leur subjectivité et celle d’autrui, une place capable de supporter la construction identitaire originelle défaillante, retrouver une identité pour dépasser le traumatique, et ouvrir le chemin d’une reconstruction. / Behind every act there is a sort of "staging", an "attempt to express" what the author cannot put into words nor metabolize, which leads him to act. In this work, amoung Authors of Infringement of Sexual Character (AISC) within familial, the aim is to understand and apprehend the conditions that triggers the act and how they affected the subject's psyche, leading him to give into the transgression.Through notions taken from the analytic's literature, in particular notions linked to the psyche's construction, to traumatic clinic or even the transgenerational transmission, we debate on the question of the influence of the environment on the individual's psyche functionning. Thereby posing hypothesis that identifications and transgenerationals repeats of traumatic origin can contribute in triggering the act, even more for AISC within familial. Could this kind of acting out then represent the consequences of a family's dynamicity experienced as "failing", or even traumatic, by the subject? Using a phenomenologic approach associated with a psychoanalytic positioning, the thorough analysis of seven case-studies could help answer those questions. The objective is to create a clinic study based on the subjective experience of each of them. This is done in hope to bring forward what could lack in their structuring, in their objectals investments and relationships.This trip through the proposed cases allow the question of whether the resolvent nature of these acting out vis-à-vis a family's dynamicity in which a traumatic experience takes its roots? Through the sexual offence, perpetrated within the family, is the subject using the body and the objectisation of another family to shout out his suffering, his "ill-being"? Is the acting out, for Authors of Infringement of Sexual Character (AISC) within familial, a consequence of a traumatic identity crisis, the need to find a sense or the search to the meaning to the subject's own existence? Through the analysis of defense mechanisms, representations, transference and counter-transference positions put in place, the goal is to help rework the senses, allow those patients to develop their elaboration capability, to give them a place, with respect to their subjectivity and that of other, a place capable of sustaining the construction of their originally deficient identity, to rediscover an identity that surpasses the trauma, and open the gates of reconstruction.
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Conséquences de l'exposition de l'insecte modèle Aedes aegypti aux polluants des eaux de surface : Des mécanismes moléculaires à la dynamique des populations / Impact of surface water pollutants on the model insect Aedes aegypti : from molecular mecanisms to population dynamics.

Prud'homme, Sophie 18 December 2015 (has links)
Les activités humaines dispersent quotidiennement une grande variété de produits chimiques dans l’environnement. Les populations d’organismes aquatiques sont ainsi exposées à des polluants chimiques tout au long de leur cycle de vie, ce qui pose la question de l’impact de ces polluants émergeants sur les écosystèmes aquatiques. Au cours de ce travail, nous avons étudié les traits d’histoire de vie de populations de moustiques Aedes aegypti exposées à trois polluants : l’ibuprofène, le bisphénol A et le benzo[a]pyrène. Nos observations rendent compte de modifications de traits d’histoire de vie susceptibles d’influencer la dynamique des populations de moustiques Aedes aegypti, observés lors d’exposition à des concentrations cohérentes avec les mesures effectuées dans l’environnement. Ces études révèlent notamment de nombreuses conséquences trans-générationnelles de l’exposition aux polluants. Une approche intégrative associant des études transcriptomique, métabolomique et hormonale réparties à différentes étapes du cycle de vie des individus exposés à l’ibuprofène a été adoptée afin de mieux comprendre les impacts de ce polluant sur les individus. Cette approche a révélé chez les larves exposées un mécanisme d’action similaire au mécanisme pharmacologique de ce médicament sur les vertébrés. Ces perturbations sont en outre accompagnées de modifications importantes de l’état physiologique de leur descendance. Ces modifications, mises en évidence notamment par la potentialisation de la signalisation hormonale par l’ecdysone ainsi que la surreprésentation des mécanismes de réponse aux stress, aboutissent à un développement plus rapide et à une meilleure tolérance de cette descendance aux périodes de jeun. Notre approche met en évidence l’intérêt de la prise en compte du cycle de vie dans sa globalité, incluant la descendance, dans l’évaluation des risques écotoxicologiques. / Human activities daily release a wide variety of chemicals in the environment. Populations of aquatic organisms are thus exposed to pollutants throughout their life cycle, raising the question of the impacts of these pollutants on aquatic ecosystems. In this work, we study life history traits of populations of Aedes aegypti mosquito exposed to three pollutants: ibuprofen, bisphenol A and benzo[a]pyrene. Our observations reveal life history traits alterations likely to affect Aedes aegypti populations dynamic at environmental concentrations, more particularly showing the importance of transgenerational effects in those modifications. An integrative approach combining transcriptomic, metabolomic and hormonal studies on several phases of the life cycle of individuals exposed to ibuprofen was adopted in order to deepen the understanding of impacts of this pharmaceutical on individuals. This approach reveals a mechanism of action similar to the pharmacological mode of action on vertebrates of this pharmaceutical. Those perturbations are associated with crucial changes in the physiological state of their progeny. The identified modifications include ecdysone signalling potentialization and stress response mechanism over-representation, leading to a faster development and an increased tolerance to starvation of this progeny. Overall, our approach highlights the importance of taking into account the all life cycle of organisms, including their progeny, in ecotoxicological risk assessment.
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Posttraumatický stres a růst u přeživších holokaustu a jejich rodin / Posttraumatic stress and growth in holocaust survivors and their families

Tanzerová, Adéla January 2018 (has links)
This master's thesis focusses on long-term effects of the Holocaust on the generation of survivors as well as on their offspring. Firstly, the theoretical part defines the terms 'stress' and 'trauma'. This is followed by an outline of possible reactions to severely stressful situations as well as questionnaires that can be used to measure the levels of traumatization. Afterwards, attention is focused on the phenomenon of posttraumatic growth, mainly based on the perspectives of L. G. Calhoun and R. G. Tedeschi who identify five domains of growth. The possibility of facilitating posttraumatic growth is briefly mentioned alongside with one inventory that can be used to measure the extent of positive change following traumatic experiences. Furthermore, the complexity of the Holocaust is discussed and generations of the Holocaust survivors and their offspring are characterised. In conclusion, attention is drawn to the studies that are concerned with the transgenerational transmission of trauma. The empirical component of the thesis is dedicated to the mapping of specific aspects of posttraumatic stress and growth in Holocaust survivors and their offspring. This data was collected by using a PTSD CheckList (PCL-C) and a Posttraumatic Growth Inventory (PTGI), and afterwards was processed by quantitative...
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Dieta hiperlipídica materna: influências sobre o comportamento maternal e o desenvolvimento da prole. / Maternal high fat diet: influences on maternal behavior and offspring development.

Marianne Orlandini Klein 22 July 2016 (has links)
Uma nutrição maternal rica em lipídios pode causar prejuízos no desenvolvimento e na vida adulta dos descendentes, como elevado risco de desenvolver alterações metabólicas e obesidade, e também parece alterar a sinalização central por opióides. Porém, estudos realizados a fim de investigar a influência da dieta hiperlipídica (HF) materna sobre o comportamento materno e o desenvolvimento da prole não são conclusivos. Este trabalho investigou a influência da dieta HF sobre a interação mãe-filhote, em duas gerações, e os efeitos imediatos e tardios sobre a prole, relacionando-os ao sistema opióide. As mães HF apresentaram prejuízos na ejeção do leite e maior expressão dos receptores opióides no hipotálamo. No geral, os descendentes HF apresentaram elevados níveis de colesterol, baixa leptina plasmática, maior expressão de peptídeos relacionados à ingestão alimentar, e menor peso. Portanto, o consumo materno de dieta HF causou alterações metabólicas, comportamentais e na expressão gênica na mãe e nos descendentes, mesmo que esses animais não tenham se tornado obesos. / A maternal nutrition high in fat may impair offspring development and adulthood, increasing the risk to develop metabolic alterations and obesity, and may modify the opioids central signaling. However, studies investigating maternal high fat (HF) diet influences on maternal behavior and offspring development are inconclusive. This study aimed to evaluate the influences of a diet high in fat on mother-pup interaction, in two generations, and its early and late effects in the offspring, connecting them to the opioid system. HF dams show decreased milk ejections and higher expression of opioid receptors in the hypothalamus. Overall, HF offspring had higher cholesterol levels, less serum leptin, higher expression of peptides related to food intake, and were lighter. Therefore, maternal intake of HF diet promoted metabolic, behavioral and gene expression alterations in the mother and her offspring, even though these animals did not become obese.

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