Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Memoria para optar al Título Profesional de Médico Veterinario / El sinciciotrofoblasto placentario (hSTB) constituye la principal barrera para el intercambio materno fetal. Es de vital importancia que se lleve a cabo un adecuado transporte de solutos y nutrientes para que el feto pueda desarrollarse de forma normal. La Restricción de Crecimiento Intrauterino (RCIU) es la incapacidad del feto para alcanzar su potencial de crecimiento, una posible causa podría ser alteraciones en el transporte a través del hSTB, ya que se han reportado cambios en cuanto a funcionalidad y expresión de algunos transportadores en esta patología, sin embargo, no se ha estudiado mayormente lo que ocurre con un tipo de proteínas de transporte denominadas canales iónicos. En particular, es de importancia entender lo que ocurre con el Maxi-canal de Cl⁻, ya que se ha visto que éste muestra alteraciones en sus características biofísicas en otra patología del embarazo, la Preeclampsia. El objetivo del presente estudio fue caracterizar las corrientes de Cl⁻ en el ovocito de Xenopus laevis trasplantado con membrana apical (MVM) proveniente de hSTB con RCIU, a través de la técnica de Voltage Clamp. Las corrientes provenientes de ovocitos inyectados fueron significativamente mayores que las obtenidas de ovocitos controles sin inyectar, evidenciando la incorporación funcional de los canales exógenos provenientes de MVM RCIU. Estas corrientes exógenas fueron sensibles a DIDS, un conocido bloqueador de canales de Cl⁻, el cual disminuyó las corrientes de manera voltaje dependiente, 45 % a -100 mV y 78 % a +40 mV, sugiriendo que las corrientes exógenas fueron principalmente de Cl⁻. En cuanto a las corrientes evocadas en ovocitos inyectados con MVM normal, no fueron significativamente distintas de las corrientes provenientes de MVM RCIU. Por otro lado, el bloqueador DIDS (ácido 4,4-diisotiocianatostilbeno-2,2 disulfónico) mostró su efecto sólo a potenciales positivos, disminuyendo las corrientes en un 36 % a +40 mV, siendo también voltaje dependiente, pero en menor magnitud / Proyecto FONDECYT 1070695

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Martina Michalská Supervisor: doc. PharmDr. Martina Čečková, Ph.D. Title of diploma thesis: Expression of selected membrane transporters in placentas of pregnant women diagnosed for preterm rupture of membranes Placenta is a key organ for pregnancy maintenance. One of its main functions is transport of compounds between mother and her fetus. The transplacental penetration is ensured due to membrane transporters that are present in the apical or basal side of trophoblast. Their expression level is affected by many physiological and pathological factors, among others it can be influenced by infection and inflamatory reaction. Inflammation is also one of the risk factors of preterm deliveries and it can be therefore assumed that these pathological states are accompanied by changes in expression of placental transporters. This study was performed using 51 placentas obtained from Faculty hospital in Hradec Králové from women who underwent preterm delivery and on 15 placentas delivered in term. The study employed quantitative RT-PCR approach. The mRNA expression of membrane transporters ABCB1, ABCG2, OATP1A2, OATP1B3, OATP2A1, OATP2B1, OATP3A1, OATP4A1 was assessed and the results were compared to...

OBJECTIVE: High prepregnancy maternal body mass index (BMI) is associated with an increased risk in childhood overweight and obesity. This study sought to expand upon the research of this phenomenon/trend by examining the role of placental weight in inter-generational obesity risk. METHODS: This prospective birth cohort study was conducted at Boston Medical Center in Boston, Massachusetts. Between 1998 and 2016, the study recruited and tracked 1,025 mother-infant pairs who have been followed from birth prospectively up to age 19 and who had data on placental pathology along with pre-, peri-, and post-natal variables, including maternal and child BMI. This study analyzed 6 Groups defined by placental weight tertiles and maternal overweight and obesity (BMI ≥ 25 kg/m2) (binary). Group 0 includes lowest placental tertile and maternal not overweight and obesity. Group 1 includes lowest placental tertile and maternal overweight and obesity. Group 2 includes middle placental tertile and maternal not overweight. Group 3 includes middle placental tertile and maternal overweight and obesity. Group 4 includes highest placental tertile and maternal not overweight. Group 5 includes highest placental tertile and maternal overweight and obesity. MAIN OUTCOMES AND MEASURES: Child BMI z-score was calculated according to United States reference data for specific age and sex. Childhood overweight and obesity was defined as an BMI in the 85th percentile or greater for age and sex. Maternal overweight and obesity was defined as a BMI of 25kg/m2 or greater, and placental weight was classified into tertiles based on sex- and gestational age. RESULTS: The mean (SD) maternal age at delivery was 28.7 (6.6) years and the mean (SD) child age at last visit was 9.5 (4.9) years. Among 1,025 mothers, 54.15% were overweight with an average BMI of 27.0 kg/m2. 68.98% of mothers were black, 76.5% never smoked, and 62.73% had less than a high school education. Among 1,025 children 447 (43.61%) were overweight. As expected, maternal overweight and obesity was associated with the highest risk for childhood overweight and obesity, with an odds ratio of 3.752 (95% CI, 2.137-6.588) as well as the largest increase in child BMI z-score. The strong association remained after adjusting for placental weight and other covariables, including birth weight. When maternal overweight and obesity and placental weight were analyzed in combined groups (0-5), they jointly increased the risk of child overweight or obesity. Using group 0 as reference, the group 5 had the highest risk of child overweight or obese and the largest increase in child BMI z-score. CONCLUSIONS: In this urban low-income prospective birth cohort, we observed a strong inter-generational link of overweight or obesity. Furthermore, there was an additive effect of maternal overweight and obesity and placental weight on child risk of overweight and obesity. Additional studies are warranted to replicate our findings and further investigate the biological pathways underlying the inter-generational obesity risk. / 2021-06-17T00:00:00Z

Orientador: Flávia Thomaz Verechia Pereira / Banca: Márcia Rita Fernandes Machado / Banca: Ricardo da Fonseca / Resumo: Para o crescimento placentário e a nutrição fetal, altas taxas de crescimento e diferenciação celular são necessárias para um balanço adequado entre proliferação e morte celular das células placentárias. Estas células possuem propriedades específicas em relação a suas funções metabólicas, endócrinas e angiogênicas, sendo fundamentais para o desenvolvimento do concepto ao longo da prenhez. Neste estudo, foi avaliada a ocorrência de proliferação celular em placentônios provenientes de conceptos bovinos transgênicos clonados (n=5) e de inseminação artificial (IA) (n=18), nos períodos de 60 e 90 dias de gestação, que tiveram seu desenvolvimento interrompido e houve a recuperação do útero gestante. As amostras de placentônio foram recortadas e fixadas em solução aquosa de paraformoldeído a 4% em tampão fosfato de sódio (PBS) a 0,1M pH 7.4, para verificação da morfologia, e realização da técnica de imuno-histoquímica. Os resultados obtidos foram comparados entre bovinos clonados transgênicos e de IA. Em todos os grupos e períodos gestacionais, o epitélio fetal apresentou marcação positiva para proliferação celular. Aos 60 dias a marcação positiva no epitélio uterino das gestações manipuladas foi pouco evidente em relação às de gestações naturais. Por sua vez aos 90 dias a imunorreatividade dos placentônios dos conceptos clonados, foi muito intensa não só no epitélio, mas também no tecido conjuntivo fetal, fato não observado na gestação natural, onde a reação positiva foi pouco evidente no tecido conjuntivo fetal. Neste estudo foi demonstrado um possível desequilíbrio nos padrões de proliferação celular nos conceptos bovinos clonados transgênicos, pois no início da gestação (60 dias) apresentaram menor atividade proliferativa e aos 90 dias um aumento, podendo ser este fato um dos fatores que levam às anormalidades placentárias. Desse modo os resultados da verificação.. / Abstract: For the placental growth and fetal nutrition, high rates of growth and differentiation are necessary for a proper balance between proliferation and cell death of placental cells. These cells have specific properties in relation to its metabolic, endocrine and angiogenic function and they are fundamental to the development of the fetus throughout pregnancy. In this study, the occurrence of cell proliferation was assessed in placentomes by cloned transgenic bovine conceptuses (n=5) and by artificial insemination (AI), in the 60 and 90 days of gestation, and they development were interrupted and recovering the pregnant uterus. The samples were cut and fixed in paraformaldehyde 4% aqueous solution in sodium phosphate buffer (PBS) 0.1M at pH 7.4, for verification of the morphology and performing immunohistochemistry. The results were compared with bovine cloned and AI. The reults obtained were compared between transgenic cloned bovine conceptuses and AI. In all groups and gestational periods, the fetal epithelium presents positive labeling to cell proliferation. In 60 days gestation the positive labeling of the manipulated gestations was less evident in relation to the natural gestations. On the other hand, in 90 days gestation the immunoreactivity of the placentomes of the cloned conceptuses was more intense, not just in the epithelium, but also in the fetal connective tissue, fact not observed in the natural gestation, were the positive reaction was less evident in the fetal connective tissue. In this study was noted a possible imbalance in the patterns of the cell proliferation in the transgenic cloned bovine conceptuses, because in the early gestation (60 days) they presented a lesser proliferative activity, and in the 90 days a increase, may be this fact one of the factors leading to placental abnormalities. Therefore, the results of verification of cell proliferation and understanding are important for the understanding of possible fails... / Mestre

Kwan Pui-Chun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 140-155). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Overview --- p.1 / Chapter 1.2 --- Iron homeostasis --- p.5 / Chapter 1.3 --- Natural Resistance Associated Marcophage Protein (Nramp) Family --- p.15 / Chapter 1.4 --- Divalent Metal Transporter 1 (DMT1) --- p.18 / Chapter 1.5 --- Iron Responsive Element (IRE) and Iron Regulatory Protein (IRP) --- p.23 / Chapter 1.6 --- Expression and localization of DMT-1 in human --- p.27 / Chapter 1.7 --- Iron and the developing feus --- p.31 / Chapter 1.8 --- Objectives of the study --- p.36 / Chapter Chapter 2 --- Materials and Method / Chapter 2.1 --- Study population --- p.37 / Chapter 2.2 --- Procedure of surgical termination of pregnancy --- p.38 / Chapter 2.3 --- Tissues collection and preparation --- p.39 / Chapter 2.4 --- Semi-quantitative Reverse Transcription-Polymerase Chain Reaction --- p.44 / Chapter 2.5 --- Immunohistochemistry --- p.49 / Chapter 2.6 --- Statistical analysis --- p.55 / Chapter Chapter 3 --- Results / Chapter 3.1 --- Description of subjects --- p.56 / Chapter 3.2 --- Existence of human DMT-1 isoforms at early pregnancy --- p.58 / Chapter 3.3 --- Relative expression of DMT-1 isoforms to β -actin mRNA expression at different week gestation --- p.67 / Chapter 3.4 --- Cellular localization of DMT-1 isoforms at early pregnancy --- p.91 / Chapter 3.5 --- Relative expression of DMT-1 proteins at early pregnancy --- p.101 / Chapter Chapter 4 --- Discussion / Chapter 4.1 --- Existence of DMT-1 at early pregnancy --- p.116 / Chapter 4.2 --- Expression of DMT-1 isoforms at early pregnancy at gene level --- p.118 / Chapter 4.3 --- Expression of DMT-1 isoforms at early pregnancy at protein level --- p.120 / Chapter 4.4 --- "Comparison expression of DMT-1 between human fetus, human adult and animal studies" --- p.121 / Chapter 4.5 --- Functional importance of DMT-1 at developing fetus at early pregnancy --- p.130 / Chapter 4.6 --- Conclusion --- p.138 / Chapter 4.7 --- Further study --- p.139 / Chapter Chapter 5 --- Reference --- p.140 / Appendix I: Calculation of EM --- p.156

Resumo: O objetivo dessa revisão foi explorar a literatura sobre a atuação das citocinas IL-10 e TNF-α na gestação, destacando aspectos de interesse para a clínica obstétrica. A literatura disponível destaca várias funções da IL-10 e do TNF-α na gestação. Via de regra, estas citocinas desempenham papéis antagônicos e dependentes do balanço entre elas, condição que é orquestrada pela função imunomoduladora específica da IL-10. O TNF-α tem ação de característica inflamatória, sendo relacionado a perdas fetais recorrentes, síndromes hipertensivas, restrição do crescimento fetal e diabete melito gestacional. Entretanto, os resultados ainda são controversos e não completamente definidos. Tais conflitos são atribuídos à heterogeneidade dos estudos, principalmente relacionada à natureza, ao tamanho amostral, aos métodos de avaliação e à multiplicidade de fatores e condições que influenciam a produção das citocinas. Estas questões são fundamentais e devem ser consideradas em futuras investigações para que resultados mais consistentes possam nortear a prática obstétrica / Abstract: The purpose of this work was to review the literature concerning the action of cytokines IL-10 and TNF-a in pregnancy, giving emphasis to aspects of interest to clinical obstetrics. The literature available highlights several IL-10 and TNF-a actions in pregnancy. These cytokines usually play balance-dependent opposing roles orchestrated by the IL-10-specific immunomodulatory function. TNF-a action is characteristically inflammatory and has been associated with recurrent fetal loss, hypertensive syndromes, fetal growth restriction and gestational diabetes mellitus. However, study results are controversial and remain not clearly defined. These conflicts are attributed to the heterogeneity of the studies, particularly regarding sample nature and size, evaluation methods, and the multiplicity of factors and conditions that influence cytokine production. These questions are fundamental, and should be addressed in future investigations so that more consistent results can be obtained and applied to obstetric practice / Orientador: Iracema de Mattos Paranhos Calderon / Coorientador: Débora Cristina Damasceno / Banca: Marilza Vieira Cunha Rudge / Banca: Estela Bevilacqua / Mestre

SK3 channels contribute to membrane repolarization and hyperpolarization that leads to both relaxation of smooth muscle and vascular branching. These two distinct properties are intensified in the SK3T/T mice possibly influencing pregnancy by dampening uterine contractions and causing dysfunctional placental development. SK3T/T mice have delayed or hindered parturition, suggesting a role for SK3 channels in labor contractions (Chapter 2 & 3). Based on these findings, we hypothesized that SK3 channel expression must be reduced late in normal pregnancy to enable the uterus to produce the forceful contractions required for parturition. The mechanism(s) downregulating this channel in the uterus during pregnancy is unknown. The SK3 gene promoter region contains two Specificity Protein (Sp) binding sites; Sp1, a transcription factor that enhances transcription of genes in response to estrogen, and Sp3, a factor that competes for the same binding motif as Sp1 to reduce gene expression (Chapter 4). SK3 channels may also be involved in the vascular remodeling that occurs during pregnancy. The SK3 channel is present in vascular endothelial cells and overexpression of this channel leads to abnormal vessel branching and an increase in vessel diameter. During pregnancy, the vascular system must adapt to accommodate dramatic increases in blood volume necessary to sustain the developing fetus. Overexpression of SK3 channels could produce abnormalities in the placental vascular network, similar to the abnormal vessel branching and vasodilatation found in the mesenteric circulation, thus leading to poor fetal outcome (Chapter 5). The aim of this research was to determine the function of the SK3 channel in pregnancy by focusing on its role in myometrial contractility in addition to identifying its role in remodeling the maternal vasculature and its impact on placental blood flow and fetal demise.

Objetivo: Determinar el valor predictivo del Índice Cerebro Placentario y del flujo anormal del Ductus Venoso de Aranzio, medido por velocimetría Doppler, en pacientes con preeclampsia, en relación a un resultado perinatal adverso. Materiales y métodos: Estudio prospectivo, no experimental, longitudinal, de tipo correlacional. Se realizaron exámenes ultrasonográficos Doppler para determinar el Índice Cerebro Placentario y el flujo anormal del Ductus Venoso de Aranzio, en los 7 días previos al parto, en 160 pacientes con diagnóstico de preeclampsia severa admitidas en la Unidad de Medicina Fetal y Diagnóstico Prenatal del Servicio de Obstetricia de Alto Riesgo del Hospital Guillermo Almenara Irigoyen – EsSalud. El resultado perinatal adverso fue definido por los siguientes parámetros: Cesárea por SFA, APGAR menor 7 a los 5´, Líquido amniótico meconial, Oligohidramnios, pH de la arteria umbilical menor 7,2, Admisión en UCI neonatal, RCIU. Se utilizó estadística descriptiva para la variable dependiente y estadística inferencial mediante el estadístico chi cuadrado (x²) y prueba exacta de Fisher, con un nivel de significancia de 0,05; confiabilidad del 95%. Además se calculó la sensibilidad, especificidad y valores predictivos positivo y negativo de la variable independiente. Conclusiones: Se ha demostrado que la alteración del Índice Cerebro Placentario y del Flujo del Ductus Venoso de Aranzio medido por flujometría Doppler fetal, detecta a más del 65% de los recién nacidos con resultado perinatal adverso e hipoxia fetal y se asocia a la ocurrencia del mismo. Además esta es una prueba predictiva, estadísticamente significativa, de RCIU y de oligohidramnios, en pacientes con preeclampsia severa. El presente estudio se realizó con un muestreo no aleatorio, por ende, este hecho de no aleatoriedad, pudiera plantear problemas de validez externa. / Objective: To ascertain the value of cerebral-placental ratio and the abnormal fluxo of Aranzio´s Ductus Venous and for identifying newborns with neonatal morbidity in pregnancies complicated by severe preeclampsia. Study Design: A longitudinal and correlational study of 160 patients with severe preeclampsia (PA > 160/110, proteinuria 3+) was performed Doppler study done by one operador within 7 days before delivery. An abnormal cerebral-placental ratio and abnormal resistance and pulsabilility index of ductus venous were used to identificate fetal asphixia (cardiac insuficiency). The results belong 5 percentile were considered abnormal. These results were matched with perinatal results considered as abnormal. Results: Maternal characteristic were: age 33, parity 1, primigravid 45%, prenatal care 85%, gestational age at enrollment 35,1 weeks. The probability of detection IUGR is 65% and oligohydramnios 61,2%. Conclusion: The cerebral-placental ratio and abnormal fluxo of Aranzio´s Ductus venous identifies 65 % or more of the newborns with severe neonatal morbidity in pregnancies with severe preeclampsia. / Tesis

Placental dysfunction is implicated in the pathogenesis of preeclampsia. Chemical signals between the placenta and maternal circulation are a suspect cause of endothelial dysfunction and maternal hypertension. This study examined select lipid mediators of inflammation produced by the placenta. Patients were recruited from Virginia Commonwealth University’s pregnancy clinics and placentas were collected at delivery. Forty-eight-hour explant cultures of villous placental tissue were used to model lipid production. Electrospray ionization mass spectrometry was used to quantify concentrations of free lipids in the culture media. Bicinchoninic acid assays were performed to quantify protein in each culture for normalization of lipid data. After analysis, it was found that severity of preeclampsia was correlated with a unique lipid profile. Pro-inflammatory hydroxyeicosatetraenoic acids and sphingolipids were elevated. Aspirin usage in patients who developed preeclampsia was found to attenuate accumulation of isoprostane oxidative stress markers and thromboxane production while preserving omega-3-fatty acid and increasing prostacyclin levels.