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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.
21

Avaliação ultrassonográfica das dimensões do timo fetal na insuficiência placentária / Ultrasonographic evaluation of fetal thymus in pregnancies with placental insufficiency

Marisa Akemi Takeno 12 February 2014 (has links)
Introdução: o timo é importante órgão linfoide do sistema imunológico. Estudos mostraram que, durante o período fetal, a atrofia desse órgão faz parte da resposta adaptativa do feto ao ambiente intrauterino adverso, como a desnutrição crônica causada pela insuficiência placentária. Essa situação pode explicar a associação entre restrição de crescimento intrauterino e as alterações no sistema imunológico após o nascimento, na infância e na adolescência. Objetivos: analisar as dimensões do timo fetal pela ultrassonografia em gestações com insuficiência placentária, comparando com gestações de alto risco sem insuficiência placentária e gestações de baixo risco. Métodos: estudo prospectivo com 30 gestações com insuficiência placentária (Doppler de artéria umbilical com índice de pulsatilidade > p95) comparadas com 30 de alto risco e 30 de baixo risco (grupo controle). Os critérios de inclusão foram: idade gestacional entre 26 e 37 semanas, feto único e vivo, ausência de malformações fetais, membranas íntegras, ausência de sinais de trabalho de parto, ausência de infecção materna ou fetal e não realização de corticoterapia antes da avaliação ultrassonográfica fetal. O timo fetal foi identificado na interface com os pulmões, na altura dos três vasos da base do coração, no corte do tórax fetal. Foram realizadas três medidas do diâmetro transverso (DT) e do perímetro (P) do timo, e as médias foram utilizadas para análise, transformadas em escores zeta, de acordo com a idade gestacional em que se efetuou a medida. Foram realizadas as medidas ultrassonográficas da circunferência cefálica (CC) e do comprimento do fêmur (CF) fetal, com as quais se calculou as relações DT/CF, DT/CC, P/CF e P/CC. Resultados: o grupo com insuficiência placentária apresentou mediana significativamente maior do escore zeta do IP da artéria umbilical quando comparado ao grupo de alto risco e controle (4,6 vs. -0,5 vs. -0,2, p < 0,001). As medidas do timo fetal no grupo com insuficiência placentária [escore zeta do DT (média=-0,69; DP=0,83) e escore zeta do P (média=-0,73; DP=0,68)] foram significativamente (p < 0,001) menores quando comparadas aos grupos de alto risco [escore zeta do DT (média=0,49; DP=1,13) e escore zeta do P (média=0,45; DP=0,96)] e controle [escore zeta do DT (média=0,83; DP=0,85) e escore zeta do P (média=0,26; DP=0,89)]. Nas relações estudadas, houve diferença significativa (p < 0,05) na média dos grupos: insuficiência placentária (DT/CC=0,10, P/CF=1,32 e P/CC=0,26); alto risco (DT/CC=0,11, P/CF=1,40 e P/CC=0,30) e controle (DT/CC=0,11, P/CF=1,45 e P/CC=0,31). Conclusão: em gestações complicadas pela insuficiência placentária, ocorre redução das dimensões do timo fetal sugerindo que pode ser decorrente da adaptação fetal ao ambiente intrauterino adverso / Introduction: thymus gland is an important lymphoid organ involved in immune response. Studies have shown that during fetal life, thymus atrophy is part of an adaptive response to a compromised intrauterine environment, like chronic malnutrition due to placental insufficiency. This may explain the association between intrauterine growth restriction and later altered immune function. Objective: to evaluate fetal thymus by ultrasonography in pregnancies with placental insufficiency and compare to high risk pregnancies without placental insufficiency and low risk pregnancies. Methods: a prospective study with 30 pregnancies with placental insufficiency (umbilical artery Doppler with pulsatility index > p95), compared to 30 high risk pregnancies and 30 low risk pregnancies (control group). The inclusion criteria were: gestational age ranging from 26 to 37 weeks, singleton pregnancies, absence of fetal malformations, intact membranes, not in labor, no signs of maternal or fetal infection, and no corticotherapy before the ultrasound evaluation. Fetal thymus was identified in its interface with the lungs, at the level of the tree-vessel view of the fetal thorax. Three measures of thymus transverse diameter (TD) and perimeter (P) were made, and the media were converted into zeta score according to the gestational age. Head circumference (HC) and femur length (F) were also measured and used in the calculation of the relations TD/F, TD/HC, P/F, P/HC. Results: the group with placental insufficiency presented median of umbilical artery PI elevated, when compared to high risk pregnancies and low risk pregnancies (4.6 vs. -0.5 vs. -0.2, p < 0.001). Fetal thymus measurements were significantly (p < 0.001) lower in pregnancies with placental insufficiency [TD zeta score (media=-0.69; SD=0.83) and P zeta score (media=-0.73; SD=0.68)] when compared to high risk pregnancies [TD zeta score (media=0.49; SD=1.13) and P zeta score (media=0.45; DP=0.96)] and control group [TD zeta score (media=0.83; SD=0.85) and P zeta score (media=0.26; SD=0.89)]. There was significant difference (p < 0,05) in the relations studied among the groups: pregnancies with placental insufficiency (TD/HC=0.10, P/F=1.32 e P/HC=0.26), high risk pregnancies (TD/HC=0.11, P/F=1.40, P/HC=0.30) and control group (DT/HC=0.11, P/F=1.45, P/HC=0.31). Conclusion: fetal thymus measurements are reduced in pregnancies with placental insufficiency, suggesting that it is a fetal adaptive response for adverse environment
22

Caractérisation des propriétés viscoélastiques du placenta par élastrographie ultrasonore transitoire bidimensionnelle / Characterization of the viscoelastic properties of placenta by two-dimensional transient ultrasonic elastography

Simon, Emmanuel 22 December 2017 (has links)
Le dépistage et le diagnostic de l’insuffisance placentaire (IP), qu’il s’agisse du retard de croissance intra-utérin (RCIU) ou de la prééclampsie (PE), sont des enjeux majeurs de santé publique. En pratique clinique, les propriétés mécaniques du placenta ne sont pas explorées, pourtant des modifications de son architecture tissulaire pourraient engendrer des variations d’élasticité. Parmi les méthodes d’élastographie ultrasonore (US), l’élastographie transitoire paraît adaptée pour une telle application. Cette technique consiste à calculer la vitesse de l’onde de cisaillement (Cs) générée par une vibration externe se propageant dans le milieu considéré. Les valeurs d’élasticité obtenues à partir des méthodes US actuelles ne sont calculées qu’à une fréquence unique. Une modification structurelle du tissu pouvant correspondre à une loi de puissance particulière de la dispersion fréquentielle de Cs, nous avons évalué l’intérêt d’une approche multifréquentielle pour distinguer l’élasticité des placentas normaux et celle de placentas présentant des signes d’IP au troisième trimestre de la grossesse. Nous avons développé un dispositif préliminaire en onde plane (pour l’exploration ex vivo) permettant de valider le principe de la méthode proposée, puis un dispositif d’élastographie transitoire 2D (exploration ex vivo et in vivo). Les données sont ajustées au moyen d’un modèle rhéologique fractionnaire dans lequel le comportement en fréquence est modélisé par une loi de puissance (exposant n du modèle). Nous avons montré que les placentas RCIU présentent des valeurs de Cs et n inférieures à celles des placentas normaux ou des PE. Cette diminution de n pourrait s’expliquer par les lésions anatomopathologiques du RCIU et la diminution de Cs est cohérente avec l’étude d’un modèle murin de RCIU par ligature utérine. Enfin, l’analyse de la dispersion fréquentielle est faisable chez la femme enceinte. La valeur ajoutée de la méthode développée devrait désormais être testée lors d’une large étude clinique. / Screening and diagnosis of placental insufficiency (PI), whether intrauterine growth restriction (IUGR) or preeclampsia (PE) are major public health issues. In clinical practice, the mechanical properties of the placenta are not explored; however changes in its tissue architecture could cause variations in elasticity. Among the ultrasound (US) elastography methods, transient elastography seemed suitable for such an application. This technique consists in calculating the shear wave speed (Cs) generated by an external vibration propagating in the medium under consideration. Elasticity values obtained from current US methods are calculated at a single frequency. As a structural modification of the tissue may correspond to a particular power law of frequency dispersion of Cs, we evaluated the interest of a multifrequency approach to distinguish the elasticity of healthy placentas and that of placentas with PI signs in the third trimester of pregnancy. We have developed a preliminary plane wave device (for ex vivo exploration) to validate the principle of the proposed method, and then a 2D transient elastography device (ex vivo and in vivo exploration). The data is adjusted using a fractional rheological model where the frequency behavior is modeled by a power law (exponent n of the model). We have shown that IUGR placentas have Cs and n values lower than those of healthy placentas or PE. This decrease in the n value could be explained by histopathological lesions of IUGR. As for the decrease of Cs in cases of IUGR, this result is consistent with the study of an IUGR rat model by uterine ligation. Finally, the frequency dispersion analysis is feasible in pregnant women. The added value of this method should now be tested in a large clinical study.
23

Etude de la perfusion placentaire par imagerie fonctionnelle sur un modèle murin de retard de croissance intra-utérin / Functional imaging of the placenta in an inrauterine growth restriction rat model by uterine ligation

Arthuis, Chloé 05 December 2016 (has links)
La distinction entre les fœtus constitutionnellement petits de ceux qui présentent une réelle restriction de croissance liée à une insuffisance placentaire n’est pas aisée avec les mesures échographiques utilisées en pratique courante. Le retard de croissance intra-utérin (RCIU) est responsable d’une part importante de la prématurité induite, et d’une augmentation du risque de mortalité et de morbidité néonatales. C’est pourquoi, l’amélioration de la connaissance de la vascularisation placentaire est indispensable pour mieux identifier et prendre en charge les situations d’hypoxie chroniques foetales associées à l’insuffisance placentaire.Pour quantifier la vascularisation les modalités d’imagerie de perfusion disponibles sont l’échographie et l’IRM. Les études évaluant la quantification de la perfusion placentaire par échographie de contraste sont peu nombreuses. Les avantages et les limites de cet examen ont été évalués sur un modèle murin de RCIU par ligature vasculaire. Ainsi, l’échographie de contraste permettait de quantifier une baisse de la perfusion placentaire sur un modèle de RCIU sans que l’on puisse observer de passage d’agents de contraste ultrasonores au travers la barrière placentaire. Les résultats obtenus ont été comparés aux données obtenues par l’IRM de perfusion. Les paramètres quantitatifs obtenus à partir des courbes de cinétiques du contraste pour chacune des deux modalités d’imagerie étaient comparables sur un modèle identique de RCIU murin. Enfin, une méthode d’étude de l’oxygénation placentaire par imagerie photoacoustique a été évaluée. Cette modalité d’imagerie non invasive permettait d’obtenir en temps réel l’oxygénation placentaire, avec cependant une profondeur limitée d’exploration. Le placenta semblait se comporter comme une réserve en oxygène au cours de l’étude d’une séquence hypoxie – hyperoxygénation maternelle avec une désaturation moins importante que celle observée dans les autres tissus maternels. / To identify fetuses small for their gestational-age who have reached their appropriate growth potential from growth-restricted fetuses due to placental insufficiency is uneasy. Intra Uterine Growth Restriction (IUGR) increases the risk for indicated preterm delivery, neonatal mortality and morbidity. Therefore, improving the knowledge of the placental perfusion is essential to better identify and manage fetal chronic oxygen deprivation associated with placental insufficiency.Contrast Enhanced Ultrasound (CEUS) and MRI are two imaging modalities available to quantify placental perfusion. However, few studies focus on the quantification of placental perfusion with CEUS. First, the advantages and limitations of CEUS were presented in an IUGR rat model by uterine ligation. The placental perfusion observed by CEUS was significantly decreased in the ligated horn. No contrast enhancement was observed in the umbilical vein or the fetus. Then, we compared the CEUS parameters to results obtained by MRI perfusion. Perfusion parameters were obtained from the signal intensity decay curve for the two imaging modalities. Results of such perfusion parameters were comparable in the same IUGR rat model. Finally, we evaluated the response of the placenta to oxygenation by photoacoustic imaging. PA imaging is a real-time, non-invasive method to evaluate placental oxygenation without contrast agents. Our results suggesting that placenta is less affected than maternal tissue by the decline in maternal oxygenation. The placenta may play an important role in protecting the feus against hypoxia.
24

Role proteinů tepelného šoku v patogenezi placentární insuficience. / The Role of Heat Shock Proteins in Pathogenesis of Placental Insufficinecy

Slabá, Kristýna January 2015 (has links)
Heat shock proteins (Hsp) are highly conserved proteins that are part of the universal stress response of the cell. Their main function is to protect cells against structural and functional damage. Organisms exposed to different forms of stress, such as e.g. a lack of nutrients or water, hypoxia, infection or inflammation, demonstrated an increased gene expression of these proteins. Pregnancy complications cause stress conditions for maternal and fetal organism, which may result in an increased gene expression of Hsp. In my thesis, I examined the concentration of extracellular mRNA for five different heat shock proteins (Hsp27, Hsp60, Hsp70, Hsp90, HspBP1) in the plasma of pregnant women and wheather this concentration is affected by possible pregnancy complications (preeclampsia, fetal growth restriction and gestational hypertension). I also investigated a possible correlation between mRNA plasma concentration for Hsp and pulsatility index values (PI) obtained by Doppler ultrasound. This research should help to invent a new predictive method for pregnancy complications, based on a detection of specific biomarkers in the first trimester of pregnancy. The research was conducted on plasma samples obtained from peripheral blood of pregnant women, whose collection was performed during clinical manifestations of...
25

Consumo alimentar de ácidos graxos em gestantes com insuficiência placentária / Food intake of fatty acids in pregnant women with placental insufficiency

Saffioti, Renata Felipe 12 March 2014 (has links)
Objetivo: analisar o consumo alimentar de energia, macronutrientes e ácidos graxos, de gestantes com insuficiência placentária, comparando com gestantes sem esta complicação obstétrica. Métodos: Estudo prospectivo, transversal e caso-controle realizado no período de fevereiro de 2012 a setembro de 2013, que incluiu gestantes que preencheram os seguintes critérios: gestação com feto único e vivo; idade gestacional superior a 26 semanas completas; diagnóstico de insuficiência placentária caracterizada pelo exame de Doppler de artéria umbilical com índice de pulsatilidade acima do p95; morfologia fetal normal ao exame de ultrassonografia; ausência de diagnóstico de diabetes; não suplementação pré-natal com ácidos graxos. Foram adotados os seguintes critérios de exclusão: diagnóstico pós-natal de anomalia do recém-nascido. O estado nutricional da gestante foi avaliado pelo índice de massa corporal (IMC) e o consumo dietético foi investigado pela aplicação do questionário de frequência alimentar, analisado pelo programa Avanutri Revolution versão 4.0, pelo qual se obteve o consumo de energia, macronutrientes (carboidratos, proteínas e lipídios) e de ácidos graxos (saturados, poli-insaturados e monoinsaturados). Foram analisados os valores absolutos obtidos e a % do valor energético total (VET) da dieta. Resultados: Foram incluídas 21 gestantes no grupo com insuficiência placentária e 21 gestantes no grupo controle. Não se constatou diferença na mediana do IMC na comparação entre os grupos (grupo estudo=26,5 kg/m2, grupo controle=28,0kg/m2; P=0,563). Houve diferença significativa na comparação do grupo com insuficiência placentária com o grupo controle na análise do consumo alimentar de: energia (2002 kcal vs. 1515 kcal, p= 0,021). Com relação ao consumo de ácidos graxos, houve diferença significativa na comparação da % do VET entre os grupos com insuficiência placentária e controle: saturados (11,5% vs. 9,3%; p=0,043); poli saturados (2,7% vs. 3,6%; p=0,029); monoinsaturados (1,2 % vs. 2,1%; p= 0,005). Não foram encontradas diferenças significativas na qualidade da dieta entre os grupos quanto ao consumo avaliado de acordo com a % do VET: carboidratos (51,5% vs. 51,8%; p= 0,831); proteínas (15,3% vs. 16,1%; p= 0,458); lipídios totais (37,8% vs. 33,0%; p=0,831). Conclusão: Gestantes com o diagnóstico de insuficiência placentária relatam consumo alimentar diferente de gestantes que não apresentam esse diagnóstico, com dieta de ácidos graxos com qualidade inferior, notadamente com maior consumo de ácidos graxos saturados, e menor consumo de poli-insaturados e monoinsaturados, além de maior consumo de energia / Objective: To analyze the dietary intake of energy, macronutrients and fatty acids of pregnant women with placental insufficiency, and to compare with pregnant women without this obstetric complication Methods : A prospective, cross-sectional and case -control study from February 2012 to September 2013, which included women who met the following criteria: singleton pregnancy with fetus alive; above 26 weeks gestation; diagnosis of placental insufficiency characterized by umbilical artery Doppler presenting pulsatility index above the p95; normal fetal morphology at ultrasound, absence of diabetes, absence of prenatal supplementation with fatty acids. We used the following exclusion criteria: neonatal diagnosis of malformation. The maternal nutritional status was assessed by body mass index (BMI) and dietary intake was investigated by applying the food frequency questionnaire analyzed by the program Avanutri Revolution version 4.0 , which was obtained by the consumption of energy, macronutrients (carbohydrates, proteins and lipids) and fatty acids (saturated, polyunsaturated and monounsaturated). We analyzed the absolute values and the % of total energy value (TEV). Results: We included 21 pregnant women in the study group with placental insufficiency and 21 pregnant women in the control group. There was no difference in median BMI between the groups (study group = 26.5 kg/m2, control group = 28.0 kg/m2, P = 0.563). Significant difference was found when the group with placental insufficiency was compared with the control group in food consumption of energy (2002kcal vs. 1515 kcal, p = 0.021). With regard to the consumption of fatty acids, there was a significant difference in the percentages of daily energy intake between the group with placental insufficiency and control group: saturated fatty acids(11.5% vs. . 9.3% , p = 0.043), polyunsaturated fatty acids(2.7 % vs. 3.6% , p = 0.029), monounsaturated fatty acids(1.2% vs. 2.1% , p = 0.005). There were no significant differences in diet quality between the groups regarding the consumption evaluated according to the % of VET: carbohydrates ( 51.5 % vs. 51.8 %, p = 0.831 ), protein (15.3 % vs. 16.1 %, p = 0.458), total fat (37.8 % vs. 33.0 %, p = 0.831) . Conclusion: Pregnant women with the diagnosis of placental insufficiency reported food consumption other than pregnant women who do not have this diagnosis with lower quality of dietary fatty acids consumption, especially with higher intake of saturated fatty acids , and lower intake of polyunsaturated and monounsaturated fatty acids, and greater energy consumption
26

Dopplervelocimetria da artéria cerebral média fetal na predição da acidemia no nascimento em gestações com insuficiência placentária / Fetal middle cerebral artery Doppler in the prediction of acidemia at birth in pregnancies with placental insufficiency

Niigaki, Juliana Ikeda 29 January 2014 (has links)
Objetivo: Avaliar a relação das alterações de fluxo na artéria cerebral média (ACM) com a ocorrência de acidemia no nascimento, em gestações com insuficiência placentária. Métodos: estudo transversal prospectivo com 91 gestações com diagnóstico de insuficiência placentária pelo Doppler de artéria umbilical (AU) alterado (índice de pulsatilidade [IP] > p95). Os critérios de inclusão foram: gestações únicas com idade gestacional (IG) superior a 26 semanas completas, membranas ovulares íntegras, ausência de anomalias cromossômicas ou congênitas. Os parâmetros da dopplervelocimetria analisados foram: IP da AU, IP da ACM, pico de velocidade sistólica (PVS) da ACM, relação cerebroplacentária (RCP) e índice de pulsatilidade para veias (IPV) do ducto venoso (DV). Foi analisada a última avaliação fetal realizada imediatamente antes do parto ou anterior à corticoterapia. Todos os parâmetros foram analisados por meio do escore zeta ou múltiplos da mediana (MoM), baseados nas médias, desvio-padrão e valores de referência para cada IG. Imediatamente após o parto, uma amostra de sangue da artéria umbilical foi obtida para a medida do pH, e os casos classificados de acordo com a presença (pH < 7,20) ou ausência de acidemia no nascimento. Resultados: Quarenta e sete (51,6%) recémnascidos apresentaram acidemia no nascimento. Os fetos que evoluíram com acidemia apresentaram valor de escore zeta do IP da AU significativamente maior (mediana 2,1 vs 1,7; p=0,014), assim como maior proporção de casos com diástole zero ou reversa (51,0% vs 31,8%; p=0,006). Quanto à ACM, o escore zeta mostrou-se significativamente menor nos casos com pH < 7,20 (mediana -2,7 vs -2,1; p=0,042), porém, em relação ao PVS não foi possível estabelecer diferença significativa entre os grupos (p=0,051). A acidemia no nascimento se associou a menores valores de RCP (mediana 0,5 vs 0,7; p=0,006), porém não ao seu escore zeta (p=0,055). Em relação ao território venoso, maiores valores do escore zeta do IPV do DV associaram-se à acidemia (mediana 2,4 vs 0,6; p=0,015). Na análise de correlação entre os valores de pH no nascimento e os resultados da avaliação da dopplervelocimetria fetal, foi constatada correlação significativa entre o valor do pH no nascimento e o escore zeta do IP da AU (rho=-0,31; p=0,003), IP da ACM (rho=0,26; p=0,012), da RCP (rho 0,25; p=0,015) e IPV do DV (rho=-0,32; p=0,002), e PVS da ACM MoM (rho=-0,21; p=0,042). A regressão logística identificou o escore zeta do IP da AU e escore zeta IP da ACM como variáveis independentes para a predição de acidemia no nascimento, classificando corretamente 67,03% dos casos. Conclusão: em casos de insuficiência placentária, o IP da AU e da ACM são preditores independentes associados com a acidemia no nascimento. Este estudo reforça que o grau de insuficiência placentária e a capacidade de adaptação fetal estão diretamente relacionados com a acidemia no nascimento / Objectives: To evaluate the relationship between middle cerebral artery (MCA) parameters and acidemia at birth, in pregnancies complicated by placental insufficiency. Methods: The study was performed as a prospective cross-sectional analysis of Doppler measurements in 91 patients with the diagnosis of placental dysfunction by abnormal umbilical artery (UA) Doppler (pulsatility index [PI] > p95). Inclusion criteria were: singleton pregnancy, intact membranes, abscence of fetal congenital or chromosomal abnormalities. The Doppler parameters analyzed were: UA PI, MCA PI, MCA peak systolic velocity (PSV), cerebroplacental ratio (CPR) and pulsatilility index for veins (PIV) of ductus venosus (DV). It was analyzed the last assessment obtained right before birth or the antenatal steroids. Umbical artey blood samples were collected at birth, and acidemia was defined as pH below 7.20. Results: Forty seven (51.6%) newborns had acidemia at birth. Those who developed acidemia showed a UA PI z-score significantly higher (median 2.1 vs 1.7, p = 0.014), as well as a higher proportion of cases with absent or reverse end diastolic flow (51.0% vs 31.8%, p = 0.006). Regarding the MAC, the PI z-score was significantly lower in cases with pH < 7.20 (median -2.7 vs. -2.1, p = 0.042), but concerning PSV z-score, no significant relation between the groups could be established (p = 0.051).The acidemia at birth was associated with lower values of CPR (median 0.5 vs 0.7, p = 0.006), but not with its z-score (p = 0.055). In relation to the venous territory, greater values of DV PIV z-score were associated with acidemia (median 2.4 vs 0.6, p = 0.015).The correlation analysis between the pH values at birth and the Doppler measurements, a significant correlation was observed between the pH at birth and UA PI z-score (rho = -0.31, p = 0.003 ), MCA PI z-score (rho = 0.26, p = 0.012), CPR z-score (rho 0.25, p = 0.015), PIV DV zscore (rho = -0.32, p = 0.002), and PSV MCA MoM (rho = -0.21, p = 0.042). Logistic regression identified the UA PI z-score and the MCA PI z-score as independent predictors for acidemia at birth, correctly classifying 67.03% of cases. Conclusion: In pregnancies with placental insufficiency, the UA PI and the MCA PI are independent predictors associated with acidemia at birth. This study reinforces that the degree of placental insufficiency and the fetal adaptation capacity are directly related to acidemia at birth
27

Dopplervelocimetria da artéria cerebral média fetal na predição da acidemia no nascimento em gestações com insuficiência placentária / Fetal middle cerebral artery Doppler in the prediction of acidemia at birth in pregnancies with placental insufficiency

Juliana Ikeda Niigaki 29 January 2014 (has links)
Objetivo: Avaliar a relação das alterações de fluxo na artéria cerebral média (ACM) com a ocorrência de acidemia no nascimento, em gestações com insuficiência placentária. Métodos: estudo transversal prospectivo com 91 gestações com diagnóstico de insuficiência placentária pelo Doppler de artéria umbilical (AU) alterado (índice de pulsatilidade [IP] > p95). Os critérios de inclusão foram: gestações únicas com idade gestacional (IG) superior a 26 semanas completas, membranas ovulares íntegras, ausência de anomalias cromossômicas ou congênitas. Os parâmetros da dopplervelocimetria analisados foram: IP da AU, IP da ACM, pico de velocidade sistólica (PVS) da ACM, relação cerebroplacentária (RCP) e índice de pulsatilidade para veias (IPV) do ducto venoso (DV). Foi analisada a última avaliação fetal realizada imediatamente antes do parto ou anterior à corticoterapia. Todos os parâmetros foram analisados por meio do escore zeta ou múltiplos da mediana (MoM), baseados nas médias, desvio-padrão e valores de referência para cada IG. Imediatamente após o parto, uma amostra de sangue da artéria umbilical foi obtida para a medida do pH, e os casos classificados de acordo com a presença (pH < 7,20) ou ausência de acidemia no nascimento. Resultados: Quarenta e sete (51,6%) recémnascidos apresentaram acidemia no nascimento. Os fetos que evoluíram com acidemia apresentaram valor de escore zeta do IP da AU significativamente maior (mediana 2,1 vs 1,7; p=0,014), assim como maior proporção de casos com diástole zero ou reversa (51,0% vs 31,8%; p=0,006). Quanto à ACM, o escore zeta mostrou-se significativamente menor nos casos com pH < 7,20 (mediana -2,7 vs -2,1; p=0,042), porém, em relação ao PVS não foi possível estabelecer diferença significativa entre os grupos (p=0,051). A acidemia no nascimento se associou a menores valores de RCP (mediana 0,5 vs 0,7; p=0,006), porém não ao seu escore zeta (p=0,055). Em relação ao território venoso, maiores valores do escore zeta do IPV do DV associaram-se à acidemia (mediana 2,4 vs 0,6; p=0,015). Na análise de correlação entre os valores de pH no nascimento e os resultados da avaliação da dopplervelocimetria fetal, foi constatada correlação significativa entre o valor do pH no nascimento e o escore zeta do IP da AU (rho=-0,31; p=0,003), IP da ACM (rho=0,26; p=0,012), da RCP (rho 0,25; p=0,015) e IPV do DV (rho=-0,32; p=0,002), e PVS da ACM MoM (rho=-0,21; p=0,042). A regressão logística identificou o escore zeta do IP da AU e escore zeta IP da ACM como variáveis independentes para a predição de acidemia no nascimento, classificando corretamente 67,03% dos casos. Conclusão: em casos de insuficiência placentária, o IP da AU e da ACM são preditores independentes associados com a acidemia no nascimento. Este estudo reforça que o grau de insuficiência placentária e a capacidade de adaptação fetal estão diretamente relacionados com a acidemia no nascimento / Objectives: To evaluate the relationship between middle cerebral artery (MCA) parameters and acidemia at birth, in pregnancies complicated by placental insufficiency. Methods: The study was performed as a prospective cross-sectional analysis of Doppler measurements in 91 patients with the diagnosis of placental dysfunction by abnormal umbilical artery (UA) Doppler (pulsatility index [PI] > p95). Inclusion criteria were: singleton pregnancy, intact membranes, abscence of fetal congenital or chromosomal abnormalities. The Doppler parameters analyzed were: UA PI, MCA PI, MCA peak systolic velocity (PSV), cerebroplacental ratio (CPR) and pulsatilility index for veins (PIV) of ductus venosus (DV). It was analyzed the last assessment obtained right before birth or the antenatal steroids. Umbical artey blood samples were collected at birth, and acidemia was defined as pH below 7.20. Results: Forty seven (51.6%) newborns had acidemia at birth. Those who developed acidemia showed a UA PI z-score significantly higher (median 2.1 vs 1.7, p = 0.014), as well as a higher proportion of cases with absent or reverse end diastolic flow (51.0% vs 31.8%, p = 0.006). Regarding the MAC, the PI z-score was significantly lower in cases with pH < 7.20 (median -2.7 vs. -2.1, p = 0.042), but concerning PSV z-score, no significant relation between the groups could be established (p = 0.051).The acidemia at birth was associated with lower values of CPR (median 0.5 vs 0.7, p = 0.006), but not with its z-score (p = 0.055). In relation to the venous territory, greater values of DV PIV z-score were associated with acidemia (median 2.4 vs 0.6, p = 0.015).The correlation analysis between the pH values at birth and the Doppler measurements, a significant correlation was observed between the pH at birth and UA PI z-score (rho = -0.31, p = 0.003 ), MCA PI z-score (rho = 0.26, p = 0.012), CPR z-score (rho 0.25, p = 0.015), PIV DV zscore (rho = -0.32, p = 0.002), and PSV MCA MoM (rho = -0.21, p = 0.042). Logistic regression identified the UA PI z-score and the MCA PI z-score as independent predictors for acidemia at birth, correctly classifying 67.03% of cases. Conclusion: In pregnancies with placental insufficiency, the UA PI and the MCA PI are independent predictors associated with acidemia at birth. This study reinforces that the degree of placental insufficiency and the fetal adaptation capacity are directly related to acidemia at birth
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Consumo alimentar de ácidos graxos em gestantes com insuficiência placentária / Food intake of fatty acids in pregnant women with placental insufficiency

Renata Felipe Saffioti 12 March 2014 (has links)
Objetivo: analisar o consumo alimentar de energia, macronutrientes e ácidos graxos, de gestantes com insuficiência placentária, comparando com gestantes sem esta complicação obstétrica. Métodos: Estudo prospectivo, transversal e caso-controle realizado no período de fevereiro de 2012 a setembro de 2013, que incluiu gestantes que preencheram os seguintes critérios: gestação com feto único e vivo; idade gestacional superior a 26 semanas completas; diagnóstico de insuficiência placentária caracterizada pelo exame de Doppler de artéria umbilical com índice de pulsatilidade acima do p95; morfologia fetal normal ao exame de ultrassonografia; ausência de diagnóstico de diabetes; não suplementação pré-natal com ácidos graxos. Foram adotados os seguintes critérios de exclusão: diagnóstico pós-natal de anomalia do recém-nascido. O estado nutricional da gestante foi avaliado pelo índice de massa corporal (IMC) e o consumo dietético foi investigado pela aplicação do questionário de frequência alimentar, analisado pelo programa Avanutri Revolution versão 4.0, pelo qual se obteve o consumo de energia, macronutrientes (carboidratos, proteínas e lipídios) e de ácidos graxos (saturados, poli-insaturados e monoinsaturados). Foram analisados os valores absolutos obtidos e a % do valor energético total (VET) da dieta. Resultados: Foram incluídas 21 gestantes no grupo com insuficiência placentária e 21 gestantes no grupo controle. Não se constatou diferença na mediana do IMC na comparação entre os grupos (grupo estudo=26,5 kg/m2, grupo controle=28,0kg/m2; P=0,563). Houve diferença significativa na comparação do grupo com insuficiência placentária com o grupo controle na análise do consumo alimentar de: energia (2002 kcal vs. 1515 kcal, p= 0,021). Com relação ao consumo de ácidos graxos, houve diferença significativa na comparação da % do VET entre os grupos com insuficiência placentária e controle: saturados (11,5% vs. 9,3%; p=0,043); poli saturados (2,7% vs. 3,6%; p=0,029); monoinsaturados (1,2 % vs. 2,1%; p= 0,005). Não foram encontradas diferenças significativas na qualidade da dieta entre os grupos quanto ao consumo avaliado de acordo com a % do VET: carboidratos (51,5% vs. 51,8%; p= 0,831); proteínas (15,3% vs. 16,1%; p= 0,458); lipídios totais (37,8% vs. 33,0%; p=0,831). Conclusão: Gestantes com o diagnóstico de insuficiência placentária relatam consumo alimentar diferente de gestantes que não apresentam esse diagnóstico, com dieta de ácidos graxos com qualidade inferior, notadamente com maior consumo de ácidos graxos saturados, e menor consumo de poli-insaturados e monoinsaturados, além de maior consumo de energia / Objective: To analyze the dietary intake of energy, macronutrients and fatty acids of pregnant women with placental insufficiency, and to compare with pregnant women without this obstetric complication Methods : A prospective, cross-sectional and case -control study from February 2012 to September 2013, which included women who met the following criteria: singleton pregnancy with fetus alive; above 26 weeks gestation; diagnosis of placental insufficiency characterized by umbilical artery Doppler presenting pulsatility index above the p95; normal fetal morphology at ultrasound, absence of diabetes, absence of prenatal supplementation with fatty acids. We used the following exclusion criteria: neonatal diagnosis of malformation. The maternal nutritional status was assessed by body mass index (BMI) and dietary intake was investigated by applying the food frequency questionnaire analyzed by the program Avanutri Revolution version 4.0 , which was obtained by the consumption of energy, macronutrients (carbohydrates, proteins and lipids) and fatty acids (saturated, polyunsaturated and monounsaturated). We analyzed the absolute values and the % of total energy value (TEV). Results: We included 21 pregnant women in the study group with placental insufficiency and 21 pregnant women in the control group. There was no difference in median BMI between the groups (study group = 26.5 kg/m2, control group = 28.0 kg/m2, P = 0.563). Significant difference was found when the group with placental insufficiency was compared with the control group in food consumption of energy (2002kcal vs. 1515 kcal, p = 0.021). With regard to the consumption of fatty acids, there was a significant difference in the percentages of daily energy intake between the group with placental insufficiency and control group: saturated fatty acids(11.5% vs. . 9.3% , p = 0.043), polyunsaturated fatty acids(2.7 % vs. 3.6% , p = 0.029), monounsaturated fatty acids(1.2% vs. 2.1% , p = 0.005). There were no significant differences in diet quality between the groups regarding the consumption evaluated according to the % of VET: carbohydrates ( 51.5 % vs. 51.8 %, p = 0.831 ), protein (15.3 % vs. 16.1 %, p = 0.458), total fat (37.8 % vs. 33.0 %, p = 0.831) . Conclusion: Pregnant women with the diagnosis of placental insufficiency reported food consumption other than pregnant women who do not have this diagnosis with lower quality of dietary fatty acids consumption, especially with higher intake of saturated fatty acids , and lower intake of polyunsaturated and monounsaturated fatty acids, and greater energy consumption
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Associação entre antecedentes morbidos, dopplervelocimetria de arterias uterinas, anticorpos antifosfolipideos e resultados perinatais adversos em um grupo de gestantes / Association between history of morbity, utrine artery Doppler flow, antiphospholipid antibodies and adverse perinatal outcome in a group of pregnant women

Sarno, Manoel Alfredo Curvelo. 02 June 2009 (has links)
Orientador: Ricardo Barini / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-12T18:24:38Z (GMT). No. of bitstreams: 1 Sarno_ManoelAlfredoCurvelo._D.pdf: 2031340 bytes, checksum: 3b2a7d30a8001e19edce044e6d8670ab (MD5) Previous issue date: 2009 / Resumo: Introdução: A presença de anticorpos antifosfolipídeos freqüentemente está associada a complicações obstétricas como aborto de repetição, óbito fetal, descolamento prematuro da placenta e pré-eclâmpsia grave e precoce. Objetivo: avaliar associação dos antecedentes mórbidos, da Dopplervelocimetria de artérias uterinas, dos anticorpos antifosfolipídeos (AAF) e resultados obstétricos/perinatais em um grupo de gestantes. Sujeitos e Métodos: foi conduzido um estudo de coorte e corte transversal, onde foram analisadas gestantes atendidas nos Ambulatórios de Pré-Natal da Unicamp que aceitaram participar do estudo. Foi aplicado um questionário sobre os antecedentes mórbidos, realização de dosagem dos AAF, realizada Dopplervelocimetria de artérias uterinas e analisada correlação com resultados obstétricos/perinatais. Resultado: foram avaliadas 385 gestantes com média de idade de 26,6 (±6,3) anos. A anticardiolipina (aCL) e o anti-ß2 glicoproteína I (anti-ß2-gpI) foram avaliados em 382 gestantes, dos quais 4,4% apresentaram o anti-ß2gpI IgM positivo, 4,7% IgG, 6,2% aCL IgG e 6,7% IgM. O anticoagulante lúpico (AL) foi avaliado em 137 gestantes com positividade em 2,3%. 33,4% das gestantes tinham, pelo menos, um antecedente obstétrico desfavorável (aborto recorrente, óbito fetal, pré-eclâmpsia, parto prematuro, filho anterior nascido com peso menor que 2.500g ou descolamento prematuro de placenta) e 2,6% tinham eventos trombóticos (infarto, acidente vascular cerebral, tromboembolismo pulmonar ou trombose venosa profunda). 16,5% tinham pelo menos um antecedente e um AAF positivo, contra 13,3% sem antecedente (p=0,44). 10% apresentavam antecedente trombótico e AAF positivo contra 14,4% sem história de evento trombótico e AAF negativo (p=0,88). As complicações obstétricas/perinatais foram avaliadas em 305 gestantes sendo que no grupo com antecedentes 31,7% evoluíram para alguma complicação obstétrica na gestação em curso contra 28,4% do grupo sem antecedente (p=0,59). Analisando o desfecho pré-eclâmpsia com pelo menos um antecedente, 7,7% x 4,5% (p=0,29), índice Apgar no 5º minuto menor ou igual a 7, 4,9% x 5,6% (p=0,57), peso abaixo de 2.500g, 15,5% x 12% (p=0,47). Quando separados os grupos com e sem antecedentes e comparados ao Doppler de artérias uterinas as mulheres que relataram peso inferior a 2.500g tiveram 4,0 [IC95: 1,16-13,7] vezes mais chance de apresentar índice de pulsatilidade acima do percentil 95 (IP>P95) e 4,68 [IC95: 1,37-15,9] quando apresentavam antecedente de elevação da pressão arterial antes das 34 semanas em gestação anterior. Não foram encontradas correlações dos outros antecedentes com o Doppler. Quando o IP>P95 houve um risco relativo (RR) de 2,77 [IC95: 1,87-4,11] para pelo menos uma complicação obstétrica/perinatal, 5,19 [IC95: 1,41-19,1] para Apgar do 5º minuto menor que 7 e 6,94 [IC95: 4,31-11,1] de peso abaixo de 2.500g. Quando associado IP>P95 e pelo menos um antecedente o RR para peso abaixo de 2.500g foi de 6,06 [IC95: 3,19-11,5] e 6,61 [IC95: 3,46-12,6] para parto antes das 37 semanas. Quando comparados os dois grupos não foi encontrada significância estatística no desfecho de pré-eclâmpsia com RR de 4.70 [IC95: 0,80-27,4]. Na avaliação do IP>P95 e AAF, 11,1% tinham o IP>P95 e pelo menos um AAF, contra 14,4% no grupo sem essas características, com Razão de Prevalência (RP)=0,77 [IC95: 0,11-4,96]. A RP para o grupo com IP>P95 e pelo menos um antecedente para a presença de pelo menos um AAF, foi de 1,75 [IC95: 0,31-9,75]. Conclusão: os antecedentes obstétricos desfavoráveis, assim como o Doppler de artérias uterinas não se correlacionaram com os AAF. O aumento da resistência ao Doppler nas artérias uterinas, isoladamente ou em associação aos antecedentes mórbidos, apresentou maior chance de complicações obstétricas/perinatais. Não foram encontradas diferenças estatísticas quando avaliado o Doppler associado com antecedentes e AAF / Abstract: The presence of antiphospholipid antibodies is often associated with obstetrical complications such as recurrent miscarriage, fetal death, placental abruption and severe early preeclampsia. Objective: To evaluate the association between a history of morbidity, uterine artery Doppler flow, serum antiphospholipid antibodies (APA) and perinatal/obstetric outcomes in a group of pregnant women. Subjects and methods: A cross-sectional cohort study evaluated pregnant women receiving care at Unicamp's prenatal clinic, who agreed to participate in the study. A questionnaire was applied to obtain data on the patient's history of morbidity, serum antiphospholipid antibodies were measured and a Doppler scan of the uterine arteries was performed. Results were correlated with obstetrical/perinatal outcome. Results: A total of 385 pregnant women with a mean age of 26.6 ± 6.3 years were evaluated. Anticardiolipin (aCL) and anti-ß2 glycoprotein I (anti-ß2-gpI) were evaluated in a group of 382 pregnant women, 4.4% of whom tested positive for anti-ß2-gpI IgM, 4.7% for IgG, 6.2% for ACL IgG and 6.7% for IgM. Lupus anticoagulant (LA) was evaluated in 137 pregnant women, 2.3% of whom tested positive. Overall, 33.4% of patients had a medical history that included recurrent miscarriage, fetal death, preeclampsia, prematurity, previous pregnancy resulting in an infant with birthweight of <2.500g or placental abruption. In addition, 2.6% had experienced a thrombotic event such as myocardial infarction, stroke, pulmonary thromboembolism or deep vein thrombosis. Overall, 16.5% of patients had at least one of the above-mentioned conditions and tested positive for APA compared to 13.3% of those with no medical history of any of these conditions (p=0.44). Ten percent of the women had experienced a thrombotic event and tested positive for APA while 14.4% had never had a thrombotic event and tested negative for APA (p=0.88). Obstetric and perinatal outcomes were analyzed in 305 women, and results showed that 31.7% of the women with a medical history of morbidities suffered at least one obstetrical complication in the current pregnancy compared to 28.4% in the group of women who had no medical history of morbidity (p=0.59). When each outcome was correlated with a history of at least one medical condition, preeclampsia was found in 7.7% of cases versus 4.5% in the group with no medical history (p=0.29), 5th minute Apgar score = 7 in 4.9% compared to 5.6% (p=0.57) and birthweight <2.500g in 15.5% compared to 12% (p=0.47). When the groups of women with and without a medical history of complication were analyzed separately and correlated with uterine artery Doppler, the women who reported having had an infant with a birthweight <2.500 grams were four times more likely (95%CI: 1.16-13.7) to have a pulsatility index (PI) above the 95th percentile and 4.68 times more likely (95%CI: 1.37-15.9) if they had a history of increased blood pressure prior to 34 weeks in their previous pregnancy. No significant correlations were found between other medical conditions and PI above the 95th percentile. When the PI was above the 95th percentile, there was a relative risk (RR) of 2.77 (95%CI: 1.87-4.11) of developing at least one obstetrical/perinatal complication, a RR of 5.19 (95%CI: 1.41-19.1) of 5th minute Apgar score being = 7 and a RR of 6.94 (95%CI: 4.31-11.1) of birthweight <2.500 grams. When PI above the 95th percentile was associated with at least one prior complication, the RR for birthweight <2.500 grams was 6.06 (95%CI: 3.19 - 11.5) and 6.61 (95%CI: 3.46 - 12.6) for delivery prior to 37 weeks. When the two groups were compared, no statistically significant correlation was found with respect to eclampsia (RR 4.70; 95%CI: 0.80 - 27.4). In the evaluation of PI above the 95th percentile and APA, 11.1% of patients had PI above the 95th percentile and at least one APA compared to 14.4% in the group without these characteristics (prevalence ratio [PR] 0.77; 95%CI: 0.11-4.96). The PR for the group with PI above the 95th percentile and at least one previous medical condition was 1.75 (95%CI: 0.31-9.75). Conclusion: Neither history of morbidity nor uterine artery Doppler was found to be associated with antiphospholipid antibodies. A significant correlation was found between increased uterine artery Doppler resistance, both when analyzed alone or in association with medical history, and obstetric/perinatal complications. No statistically significant differences were found between uterine artery Doppler associated with medical history and antiphospholipid antibodies / Doutorado / Tocoginecologia / Doutor em Tocoginecologia
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Využitie extracelulárnych nukleových kyselín na neinvazívnu prenatálnu diagnostiku monogénne dedičných porúch, komplikácií tehotenstva asociovaných s placentárnou insuficienciou a Downovho syndrómu / The use of cell-free nucleic acids in maternal plasma for non-invasive prenatal diagnosis of monogenic diseases, placental insufficiency-related complications and Down syndrome

Veselovská, Lenka January 2011 (has links)
Since the discovery of cell-free fetal DNA in peripheral blood of pregnant women, cell-free nucleic acids in maternal plasma are explored in relation to non-invasive prenatal diagnosis of various fetal conditions and pregnancy complications. Non-invasive prenatal diagnosis of monogenic diseases represented by TSC1-linked tuberous sclerosis could be achieved by detection of paternally-inherited mutant allele in the pool of maternal alleles in plasma. Reliability of detection of mutant allele could be improved by simultaneous mutation haplotype analysis or detection of universal fetal marker. None of the 3 methods (allele- specific real-time PCR, SNaPshot minisequencing and quantitative fluorescent PCR) evaluated using artificial mixtures and maternal plasma samples reliably and accurately detected low-frequency allele distinguished by point mutation, SNP or microsatellite in TSC1 gene or in its close proximity. We developed a strategy for prediction of proportion of informative couples for panel of SNPs of interest that can be applied to any monogenic disease. Exploiting differential methylation of promoters of genes RASSF1A, HLCS and OLIG2 in maternal and fetal genome, we failed to establish functional fetal marker. MicroRNAs of placental origin released into plasma could serve as biomarkers of...

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