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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.
51

Croissance chez le grand prématuré et devenir neurologique : étude d'association entre les troubles de la croissance anté et post-nataux et le développement neurologique chez les grands prématurés à partir de la cohorte Epipage / Growth in preterm and neurologic outcome : association between growth before and after birth and neurologic outcome in extreme preterm newborn from epipage cohort study

Guellec-Renne, Isabelle 08 December 2016 (has links)
Les objectifs de cette thèse étaient de définir le retard de croissance intra-utérin chez le nouveau-né prématuré, d’étudier ses conséquences en terme de morbidité néonatale et de pronostic à long terme et d’évaluer les liens existant entre retard de croissance intra-utérin, croissance extra-utérine et pronostic des prématurés. Nous avons mis en évidence dans un premier temps que le seuil strict de définition d’un « nouveau-né petit pour l’âge gestationnel» ne pouvait se limiter dans le cadre de la prématurité au 10ème percentile mais s’étendre au-delà, au moins jusqu’au 20ème percentile. Par ailleurs, se limiter au poids n’était pas suffisant et qu’une définition par l’association entre poids et périmètre crânien était pertinente en terme de pronostic tant à court qu’à long terme.Nous avons montré que la restriction de croissance intra-utérine était associée au pronostic neurologique des grands prématurés en terne de déficience cognitive et difficultés scolaires essentiellement et ce même pour des prématurés modérés et une restriction de croissance peu sévère et que l’effet du retard de croissance était modulé selon l’âge gestationnel de naissance. Concernant la croissance extra-utérine, nous avons montré qu’elle était elle-même associée au pronostic neurologique des prématurés mais que cet effet était variable selon la croissance anténatale.Enfin, nous nous sommes interrogés sur les conséquences à court terme des efforts faits par les néonatologistes afin d’optimiser la croissance post-natale des prématurés par une revue de la littérature et montré qu’ils existaient des anomalies métaboliques engendrées par une nutrition agressive qu’il convenait de surveiller. / Our main objectives were to define intrauterine growth restrictions in preterm infants to study its consequences in terms of neonatal morbidity and long-term prognosis and also assessment to study the relationship between intrauterine growth restriction, extra-uterine growth and neurological outcomes.We showed initially that strict threshold definition of a "small for gestational age" preterm could not be limited in the context of prematurity in the 10th percentile, but extend beyond, at least to the 20th percentile. Furthermore, to define growth restriction studying, weight was not enough. A definition by the association between weight and head circumference was relevant in terms of prognosis in both the short and long term.We found that growth restriction in very preterm and neurological outcome were significantly associated. Small for gestational age preterm infants were more likely to have cognitive impairment and school difficulties even for moderate preterm and moderate growth restriction. Gestational age was an important factor that modulates the association between growth restriction and outcome. Concerning extra-uterine growth, we have shown that it was associated with neurological outcome but this effect varied with antenatal growth pattern.Finally, we studied by literature review, the short-term consequences of optimized postnatal growth of premature infants and showed metabolic abnormalities caused by an aggressive nutrition that required necessary monitoring.
52

Inflammation and Altered Signaling in Obstetric Pathologies

Tsai, Ya-Fang 12 August 2021 (has links)
The purpose of this research project was to elucidate the molecular interactions and detail the signaling pathways in obstetric pathologies. This work first seeks to understand inflammation related complications relevant to obstetrics. Prior research in our lab identified the implications of the receptor of advanced glycation end products (RAGE) during inflammatory response in the placenta. Current work identified the presence of DNA double-strand breaks (DNA-DSBs) in inflammation associated pregnancy complications of preeclampsia (PE) and preterm labor (PTL) and demonstrated the positive role of RAGE in repairing the damage. The confluent relevance of disrupted mitochondrial function and inflammation has been recognized in the etiology of numerous chronic diseases. Our current studies aim to understand the connections between energy metabolism and inflammation in pathologies of pregnancy complications. Previous research conducted in our laboratory has demonstrated the mediation of the Gas6/Axl pathway on the mechanistic target of rapamycin (mTOR), an important metabolic molecule. We observed the negative regulation of Gas6 treatment on the mTOR pathway and its negative effects on trophoblast cell invasion. In the current study looking at the aspect of energy regulation, we identified the activation of placental mTOR in gestational diabetes mellitus (GDM) and its decrease during PE and intrauterine growth restriction (IUGR). We further evaluated the regulation of mTOR on its downstream effector pyruvate kinase M2 (PKM2). We found that inhibition of mTOR decreased PKM2 activation; while PKM2 activation positively regulated trophoblastic invasion and rescued negative effects observed in our second-hand smoke IUGR murine model. Our work has opened a new direction of placental research, especially in pregnancy complications stemming from genomic instability. We also clarified details of mTOR and PKM2 meditated metabolic signaling that are crucial for future investigation on the dynamic metabolic regulation during pregnancy.
53

Avaliação dos desfechos maternos e perinatais em gestantes portadoras de Lúpus Eritematoso Sistêmico

França, Maria Laura Marconi January 2020 (has links)
Orientador: Leandro Gustavo de Oliveira / Resumo: Introdução: O Lúpus Eritematoso Sistêmico (LES) é uma doença sistêmica de caráter autoimune, que acomete mulheres em idade reprodutiva, sendo que a inter-relação entre a doença e a gestação determina importantes desfechos maternos e perinatais. Objetivos: Descrever os desfechos maternos e perinatais em gestações de pacientes portadoras de LES e avaliar o impacto da nefrite lúpica sobre os resultados encontrados. Métodos: Este é um estudo observacional descritivo desenvolvido para avaliar as inter-relações entre gestação e lúpus eritematoso sistêmico em pacientes atendidas na Maternidade do Hospital das Clínicas da Faculdade de Medicina de Botucatu – HCFMB. O período de estudo foi de janeiro de 2010 a agosto de 2019. Resultados: Foram avaliadas 38 gestações em 31 pacientes com LES. A média das idades foi de 27,4 + 6 anos. A média das idades gestacionais ao nascimento foi de 36 + 3 semanas. As principais intercorrências observadas foram: anemia (39,4%), nefrite lúpica (29%) e hipertensão arterial crônica (10,5%). Hidroxicloroquina foi utilizada em 47,4% das gestações. Em 51,4% das pacientes houve necessidade de antecipação do parto e em 13,1% houve piora da função renal. A incidência de pré-eclâmpsia foi de 19,4%. Prematuridade ocorreu em 20% dos casos e restrição de crescimento fetal, em 19,4%. Nefrite lúpica determinou maior ocorrência de flare (p<0,05) e maior necessidade de antecipação do parto (p< 0,05). Conclusão: O presente estudo permitiu avaliar a inter-relação entre L... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Introduction: Systemic Lupus Erythematosus is an autoimmune systemic disease that affects women of reproductive age, and the interrelation between disease and pregnancy determines important maternal and perinatal outcomes. Objectives: To describe maternal and perinatal outcomes in pregnancies of patients with SLE and to evaluate the impact of lupus nephritis on the results found. Methods: Descriptive observational study developed to assess the interrelation between pregnancy and systemic lupus erythematosus in patients attended at the Maternity of the Clinics Hospital from Botucatu Medical School – HCFMB. The study period corresponded to January 2010 until August 2019. Results: Thirty-eight pregnancies were evaluated in 31 patients with SLE. Their average age was 27.4 + 6.0 years. The average gestational age at birth was 36 + 3 weeks. The main clinical complications observed were anemia (39.4%), lupus nephritis (29%) and chronic hypertension (10.5%). In 51,4% of the patients, it was necessary to anticipate delivery and in 13.1%, there was worsening of the renal function. Prematurity occurred in 20% of cases and FGR in 19,4%. Hydroxicloroquine was used in 47,4% of the pregnancies. Lupus nephritis determined a higher occurrence of flare (p<0.05) and a greater need to anticipate delivery (p<0.05). Conclusion: The present study made it possible to relate the main clinical characteristics and the maternal and perinatal outcomes from the pregnant women with SLE treated at the prena... (Complete abstract click electronic access below) / Mestre
54

The Role of Hypoxia on Pyruvate Kinase M2, mammalian Target of Rapamycin, Mitochondrial Function, and Cell Invasion in the Trophoblast

Kimball, Rebecca Lutz 01 March 2016 (has links) (PDF)
This thesis will be organized into two chapters discussing the role of hypoxia in the human placenta. The goal of this thesis is to characterize pyruvate kinase M2, mammalian target of rapamycin, mitochondrial function, and cell invasion in hypoxic conditions in the trophoblast. Understanding the mechanisms of placental metabolism can lead to further treatments for placental diseases. Chapter one covers the background of intrauterine growth restriction, hypoxia, placental metabolism, and pyruvate kinase M2 (PKM2). Little is currently understood about the role of the mitochondria in placental diseases. Expression of PKM2, trophoblast cell invasion, and mitochondrial function is shown to be inhibited by hypoxia. PKM2 inhibition decreases trophoblast cell invasion and nuclear expression of PKM2, but increases mitochondrial function. Studying how hypoxia affects the placenta during placental diseases can help clarify the mechanisms by which these diseases occur. Chapter two further characterizes the background of intrauterine growth restriction and hypoxia. It also covers the background of mammalian target of rapamycin. The objective of this chapter was to assess activated mTOR in the trophoblast in hypoxia. Decreased placental and fetal weights, as well as trophoblast cell invasion were observed in hypoxia. A decrease in the activation of mTOR was also found in the hypoxic placenta. This study could provide insight into the physiological relevance of the pathways and could be targeted to help alleviate placental diseases.
55

YB-1 is Altered in Pregnancy-Associated Disorders and Affects Trophoblast in Vitro Properties via Alternation of Multiple Molecular Traits

Stojanovska, Violeta, Shah, Aneri, Woidacki, Katja, Fischer, Florence, Bauer, Mario, Lindquist, Jonathan A., Mertens, Peter R., Zenclussen, Ana C. 19 December 2023 (has links)
Cold shock Y-box binding protein-1 (YB-1) coordinates several molecular processes between the nucleus and the cytoplasm and plays a crucial role in cell function. Moreover, it is involved in cancer progression, invasion, and metastasis. As trophoblast cells share similar characteristics with cancer cells, we hypothesized that YB-1 might also be necessary for trophoblast functionality. In samples of patients with intrauterine growth restriction, YB-1 mRNA levels were decreased, while they were increased in preeclampsia and unchanged in spontaneous abortions when compared to normal pregnant controls. Studies with overexpression and downregulation of YB-1 were performed to assess the key trophoblast processes in two trophoblast cell lines HTR8/SVneo and JEG3. Overexpression of YB-1 or exposure of trophoblast cells to recombinant YB-1 caused enhanced proliferation, while knockdown of YB-1 lead to proliferative disadvantage in JEG3 or HTR8/SVneo cells. The invasion and migration properties were affected at different degrees among the trophoblast cell lines. Trophoblast expression of genes mediating migration, invasion, apoptosis, and inflammation was altered upon YB-1 downregulation. Moreover, IL-6 secretion was excessively increased in HTR8/SVneo. Ultimately, YB-1 directly binds to NF-κB enhancer mark in HTR8/SVneo cells. Our data show that YB-1 protein is important for trophoblast cell functioning and, when downregulated, leads to trophoblast disadvantage that at least in part is mediated by NF-κB.
56

Mechanisms of Inverted formin 2-mediated intracellular trafficking, invasion, and placentation in mouse and human pregnancy

Lamm, Katherine Young Bezold 07 June 2018 (has links)
No description available.
57

Epidemiological Studies of Preeclampsia : Maternal &amp; Offspring Perspectives

Gunnarsdóttir, Jóhanna January 2017 (has links)
Preeclampsia is a placental-related disorder characterized by generalized endothelial activation. Vascular predisposition is associated with the occurrence of preeclampsia and the recurrence risk is substantial. Onset of preeclampsia is preceded by placental hypo-perfusion, and placental over-production of vasoconstrictive agents might explain symptoms such as hypertension and proteinuria. Preeclampsia is associated with the birth of small-for-gestational-age (SGA) infants. The trajectory of postnatal growth in SGA-born children is described as catch-up, but it is unclear whether prenatal preeclampsia is independently associated with postnatal growth. The objectives were: firstly, to study the association between partner change and prior miscarriages on the occurrence of preeclampsia and SGA; secondly, to study postnatal growth in children prenatally exposed to preeclampsia; and thirdly, to address the association between blood pressure (BP) changes during pregnancy and risks of preeclampsia and SGA. Population-based cohort studies were performed with information from the following registers: Swedish Medical Birth Register, Uppsala Mother and Child Database and Stockholm-Gotland Obstetric Database. Associations were estimated with logistic and linear regression analyses, with adjustments for maternal characteristics, including body mass index, pre-gestational diseases and socioeconomic factors. The results were, firstly, that partner change was associated with preeclampsia and SGA birth in the second pregnancy but depended on the outcome of the first pregnancy, and that a history of recurrent miscarriages was associated with increased risks of preeclampsia and SGA. Secondly, prenatal exposure to preeclampsia was associated with increased offspring growth in height during the first five years. This association was also seen in children born with normal birth weight for gestational age. Thirdly, pre-hypertension in late gestation and elevated diastolic BP from early to mid-gestation were both associated with SGA birth. Further, women with pre-hypertension in early gestation without lowered diastolic BP until mid-gestation seemed to represent a risk group for preeclampsia. To conclude, the importance of previous pregnancy outcomes in the antenatal risk evaluation was highlighted. Secondly, the results imply that postnatal growth trajectory is related to maternal preeclampsia, in addition to SGA. Thirdly, the association between BP changes within a normal range and SGA may challenge the clinical cut-off for hypertension in pregnancy.
58

Detekce extracelulárních mikroRNA v mateřské cirkulaci - diagnostika a prognostika těhotenských komplikací / Detection of extracellular microRNAs in maternal circulation - diagnosis and prognosis of pregnancy related complications

Ondráčková, Markéta January 2013 (has links)
MicroRNAs (miRNAs) are small noncoding RNAs of length 18 to 25 nucleotides that regulate gene expression posttranscriptionally. Expression of some miRNAs is tissue specific. I assumed that pregnancy induced complications associated with placental insufficiency could be characterized by a unique profil of placental-specific miRNAs in maternal circulation. I measured concentration and gene expression of selected miRNAs (miR-516-5p, miR-517*, miR-518b, miR-520a*, miR-520h, miR-525 and miR-526a) in the plasma of patients with preeclampsia (PE), fetal growth restriction (FGR) and gestational hypertension (GH). The control group consisted of patients with a normal course of pregnancy (FG). I processed 168 plasma samples, the representation of individual diagnosis were as follows: PE 63, FGR 27, GH 23, FG 55. Detection and quantification was carried out by quantitative real-time PCR. I identified three miRNAs with elevated levels in a group of preeclamptic patients: miR-517*, miR-520a* and miR-525. The severity of the PE, which was characterized by a form of the disease (mild or severe PE) and term (before or after the 34th week of pregnancy), did not have a statistically significant effect on the levels of miRNAs. More than a quarter of patients had PE superimposed on previous hypertension. Previous history of...
59

Postpartální expresní profil kardiovaskulárních microRNA ve vztahu k těhotenským komplikacím - studie matek 3-10 let po porodu / Postpartal expression profile of cardiovascular microRNAs with regard to occurrence of pregnancy-related complications - study on mothers 3-10 years after the delivery

Marvanová, Veronika January 2018 (has links)
The aim of this study was to investigate gene expression of cardiovascular miRNAs in peripheral blood of mothers after delivery. MiRNAs are small non-coding RNAs, which significantly modulate posttranscriptional adjustments of mRNA and thus regulate gene expression across biological processess. Dysregulation of miRNAs is associated with many pathological phenomena, thanks that we can use them for diagnosis and potentionaly we can treat these diseases by the manipulation of miRNA gene expression. We examined gene expression of circulating miRNAs associated with cardiovascular diseases, and we investigated, how the expression profile depends on pregnancy course and manifestation of pregnancy-related complications. For this purpose we examined material from 221 mothers 3-10 years after delivery. A group with identical pregnancy-related complication was always compared with a group of mothers after physiological pregnancy. Gene expression of 29 cardiovascular miRNAs in peripheral blood was studied using reverse transcription and quantitative real-time PCR. It was confirmed, that the expression profile of miRNAs differed between pregnancy-related complications and physiological controls. We also confirmed, that the profile of gene expression discovered at mothers 3-10 years after delivery was different...
60

Reprodutibilidade da avaliação Doppler do istmo aórtico fetal entre 32 e 36+6 semanas de gestação / Reproducibility of Doppler assessment of the fetal aortic isthmus at 32-36+6 weeks\' gestation

Campos, Victor Paranaiba 20 December 2018 (has links)
Introdução: O istmo aórtico (IAo) fetal é um pequeno segmento vascular localizado entre a origem da artéria subclávia esquerda e a extremidade aórtica do canal arterial, que reflete o equilíbrio entre a impedância ao fluxo no território cerebral e na circulação fetal periférica. Considerado o único shunt arterial verdadeiro entre os sistemas vasculares direito e esquerdo, seu fluxo alterado se associa a resultados perinatais adversos, incluindo aumento da mortalidade fetal e morbidade neurológica, especialmente em fetos com insuficiência placentária e restrição de crescimento. Justificativa: Não há protocolo mundial estabelecido definindo conduta clínica baseada na avaliação Doppler do istmo aórtico fetal, havendo espaço para que sua análise seja incorporada como justificativa para indicação do parto e proteção contra injúrias perinatais. Entretanto, implementar novas medidas à prática clínica requer a demonstração de quão confiáveis e reprodutíveis são os resultados obtidos, o que contribui para a garantia de qualidade em sua utilização. Objetivos: Estimar a reprodutibilidade intra e interobservador do índice de pulsatilidade do istmo da aorta fetal (IAo-IP) no terceiro trimestre de gestação (32 a 36+6 semanas), e determinar qual das aquisições, longitudinal ou transversal, produz medidas com melhores confiabilidade e concordância. Métodos: Estudo observacional (transversal) para o qual foram convidadas a participar gestantes no terceiro trimestre de gestação (32 a 36+6 semanas) que preenchiam os critérios de elegibilidade. O IAo-IP foi obtido por dois observadores, que utilizaram os planos longitudinal e transversal para as aquisições, realizadas de forma completamente independente, sem que tivessem conhecimento dos valores das próprias medidas, tampouco das medidas do outro observador. Os dados foram apresentados como média ± DP (desvio-padrão), mediana, mínimo e máximo; A reprodutibilidade foi avaliada pelo coeficiente de correlação intraclasse (ICC). Resultados: As principais características das 49 gestantes foram: média de idade de 26.3 ± 4.7 anos, variando entre 18 e 40 anos, com média da idade gestacional de 33.6 ± 1.5 semanas e índice de massa corporal de 27.9 ± 4.5 Kg/m2. Os resultados dos IP obtidos do estudo Doppler espectral do istmo aórtico fetal pela via longitudinal, demonstraram uma média de 2.75 ± 0.46 para o observador A, 2.53 ± 0.38 para o observador B, e 2.74 ± 0.58 para a segunda medida do observador A. Para a via transversal, as médias foram de 2.75 ± 0.46 para o observador A, 2.53 ± 0.38 para o observador B, e 2.74 ± 0.58 para a segunda medida do observador A. A avaliação Doppler do istmo aórtico fetal no plano longitudinal apresentou ICC de 0.25 na comparação entre os observadores (interobservador), e de 0.42 para a análise intraobservador. No plano transversal, os coeficientes obtidos foram de 0.18 e 0.43 respectivamente para as análises inter-observador e intraobservador. Conclusões: Embora o papel do istmo aórtico na hemodinâmica fetal esteja bem estabelecido, o presente estudo demonstrou que sua reprodutibilidade no terceirotrimestre (32 a 36+6 semanas) é fraca, logo, a medida do IAo-IP deve ser interpretada com cautela, desencorajando seu emprego na prática clínica. Os estudos que examinam aperfeiçoamentos técnicos para melhorar a sua reprodutibilidade devem ser incentivados / Introduction: The fetal aortic isthmus (AoI) is a small vessel located between the origin of the left subclavian artery and the aortic extremity of the arterial ductus, which reflects the balance between the impedance of the brain and systemic circulation of the fetus. Known as the only arterial shunt regarding both right and left vascular systems, its abnormal flow is associated to adverse perinatal outcomes, including high fetal mortality and neurological morbidity, especially among placental insufficiency and growth-restricted fetuses. Rationale: There is no established global protocol defining clinical management based on the Doppler evaluation of the fetal aortic isthmus, allowing its analysis to be incorporated as a reason to indicate delivery and protection against perinatal injury. However, implementation of new methods to clinical practice requires demonstration of how reliable and reproducible the results are, which contributes to quality assurance in their use. Objectives: To estimate the intra and interobserver reproducibility of the fetal aortic isthmus pulsatility index (IAo-PI) in the third trimester of gestation (32 to 36+6 weeks), and to determine which of both longitudinal and transversal acquisitions show better reliability and agreement. Methods: Observational (cross-sectional) study in which were invited to participate pregnant women in the third trimester of gestation (32 to 36+6 weeks) who met the eligibility criteria. The AoI-PI was obtained by two observers, who used the longitudinal and transverse plans for the acquisitions, performing independent acquisitions and blinded analysis. Data were presented as mean ± SD (standard deviation), median, minimum and maximum. The reproducibility was evaluated by the intraclass correlation coefficient (ICC). Results: The main characteristics of the 49 pregnant women were: mean age of 26.3 ± 4.7 years, ranging from 18 to 40 years, with mean gestational age of 33.6 ± 1.5 weeks and body mass index of 27.9 ± 4.5 kg/m2. The results of the PI obtained from the spectral Doppler evaluation of the fetal aortic isthmus, regarding the longitudinal plane, have demonstrated an average of 2.75 ± 0.46 for observer A, 2.53 ± 0.38 for observer B, and 2.74 ± 0.58 for the second measurement of observer A. For the transversal plane the mean values were 2.75 ± 0.46 for the observer A, 2.53 ± 0.38 for the observer B, and 2.74 ± 0.58 for the second measurement of the observer A. The Doppler evaluation of the fetal aortic isthmus in the longitudinal plane has shown a ICC of 0.25 in the comparison between the observers (interobserver), and 0.42 for the intraobserver analysis. In the transversal plane, the coefficients obtained were 0.18 and 0.43 respectively for the interobserver and intraobserver analysis. Conclusions: Although the role of the aortic isthmus in fetal hemodynamics is well established, the present study have reported that its reproducibility in the third trimester (32 to 36+6 weeks) is very poor, so the measurement of the AoI-PI should be interpreted with caution, discouraging its use in clinical practice. Studiesexamining technical amendments to improve its reproducibility should be encouraged

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