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.

OBJETIVO: Avaliar o comportamento alimentar de recém-nascidos (RN) pequenos (PIG) e grandes (GIG) para a idade gestacional através de questionário específico e comparar com RN adequados para a idade gestacional (AIG). METODOLOGIA: Estudo de coorte prospectivo, cuja primeira fase consistiu na realização de uma entrevista para coleta de dados da mãe da gestação e do parto, bem como de dados socioeconômicos, com mães que tiveram seus filhos a termo no Hospital de Clínicas de Porto Alegre. Na segunda fase do estudo foi aplicado o questionário Baby Eating Behaviour Questionnaire (BEBQ) através de contato por telefone, com 1 mês do nascimento. RESULTADOS: Foram avaliados 126 RN (43 AIG, 43 PIG e 40 GIG). As análises não demonstraram diferenças significativas nos principais dados demográficos e perinatais em relação aos diferentes grupos de estudo. No entanto, foi observada uma maior escolaridade em mães de RN PIG (p=0,004) e uma menor prevalência de aleitamento materno exclusivo até a alta hospitalar em RN GIG (p=0,002). A análise de variância não encontrou diferença significativa entre os grupos em relação aos domínios do BEBQ, mesmo quando corrigido por sexo do RN. CONCLUSÃO: O estudo demonstrou que alterações do comportamento alimentar ainda não estão presentes com 1 mês de vida, sugerindo que não são inatas, e sim desenvolvidas com o passar do tempo. O estudo tem como limitação as avaliações do crescimento baseadas em registros de terceiros. / OBJECTIVE: To evaluate feeding behavior of infants born small (SGA) and large (LGA) for gestational age using a questionnaire, and compare them with infants born adequate for gestational age (AGA). METHODS: Prospective cohort study was carried out in which the first phase consisted of an interview about gestation and delivery, as well as socioeconomic data, with mothers who had their babies born at term in the Hospital de Clínicas de Porto Alegre. In the second phase of the study, the Baby Eating Questionnaire (BEBQ) was applied through telephone interview 1 month of birth. RESULTS: 126 infants (43 AGA, 43 SGA and 40 LGA) with a mean gestational age of 39.4 weeks were assessed. The analyses did not show significant differences in the main demographic and perinatal data between the different study groups. However, a higher level of schooling was observed in mothers of SGA infants (p = 0.004) and a lower prevalence of exclusive breastfeeding in the LGA (p = 0.002). The analysis of variance found no significant difference between the groups in any of the BEBQ domains, even when corrected for the sex of the baby. CONCLUSION: This study demonstrated that changes in feeding behavior are not yet present at 1 month of age, suggesting that they are not innate, but developed over time. The study is limited to growth assessments based on third-party records.

Introdução: Sabe-se que os fatores angiogênicos e antiangiogênicos encontram-se alterados nas gestações com pré-eclâmpsia (PE), mas se desconhece seu comportamento nestes recém-nascidos (RNs). Objetivo: Dosagem do vascular endothelial growth factor (VEGF), soluble fms-like tyrosine kinase-1 (sFtl-1) e heterodímero vascular endothelial growth factor/placental growth factor (VEGF/PlGF) em pré-termos filhos de mães com PE. Métodos: Incluídos: RNs com peso de nascimento < 2.000 g e idade gestacional (IG) ≤ 34 semanas, divididos em dois grupos: filhos de mães com e sem PE. Excluídos: RNs transferidos de outra instituição com mais de 72 horas de vida, óbito antes da coleta dos exames, malformação congênita maior, erros inatos de metabolismo, gestações múltiplas, mães com infecção do grupo sífilis, toxoplasmose, rubéola, citomegalovírus, herpes (STORCH) ou vírus da imunodeficiência humana (HIV) e doença autoimune. Coletado sangue nas primeiras 72 horas de vida, e nos RNs que permaneceram internados, foi realizada uma segunda coleta com 28 dias. Foi utilizado método ELISA para a dosagem do VEGF, sFlt-1 e VEGF/PlGF. Resultados: Incluídos: 88 pacientes (37 filhos de mães com PE, 51 sem PE) com IG de 29,12 ± 2,96 semanas e peso de nascimento de 1223,80 ± 417,48 g. O VEGF foi menor no grupo com PE [32,45 (6,36-85,75) x 82,38 (35-130,03) pg/mL], p = 0,001 e o sFlt-1 foi maior no grupo com PE [1338,57 (418,8-3472,24) x 318,13 (182,03-453,66) pg/mL], p < 0,001. Na análise multivariada, o VEGF foi 80% menor e sFlt-1 13,48 vezes maior no grupo com PE. O sFlt-1 foi maior nos RNs pequenos para idade gestacional (PIG) do que nos adequados para idade gestacional (AIG) [1044,94 (290,64-3472,24) x 372,67 (236,75-860,14) pg/mL], p = 0,013. No grupo com PE, houve um aumento [≠ 151,71 (76,55-226,86); p < 0,001] entre as dosagens do VEGF entre a primeira e a segunda coleta com 28 dias, já o sFlt-1 diminuiu [≠ 1941,44 (2757,01-1125,87); p < 0,001] entre as duas dosagens. O VEGF/PlGF foi maior nos filhos de mães com PE [20,69 pg/mL (12,79-52,86) x 12,19 pg/mL (0,03 -21,58)], p = 0,003. Esses achados mantiveram-se na análise multivariada, com o VEGF/PlGF 1,05 vezes maior nos filhos de mães com PE. Os níveis de VEGF/PlGF foram inversamente proporcionais ao peso de nascimento, com p < 0,001 e r = - 0,418. Na segunda coleta com 28 dias de vida não houve diferença entre os dois grupos. Conclusão: Os maiores níveis de sFlt-1 e VEGF/PlGF e menores níveis de VEGF no grupo com PE, assim como maiores concentrações de sFlt-1 nos PIG refletem uma predominância dos mecanismos antiangiogênicos na PE e na restrição de crescimento. Os níveis de VEGF/PlGF também foram relacionados ao peso de nascimento, sendo inversamente proporcionais. O estado antiangiogênico da PE tende à normalização com 28 dias de vida. / Background: It is known that angiogenic and antiangiogenic factors are altered in pregnant women with preeclampsia (PE), but the pattern of expression of these factors in their newborn infants remains unknown. Objective: To measure vascular endothelial growth factor (VEGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and vascular endothelial growth factor/placental growth factor (VEGF/PlGF) heterodimer levels in preterm neonates born to mothers with PE. Methods: Neonates with birth weight < 2,000 g and gestational age ≤ 34 weeks were included and divided into two groups: born to mothers with and without PE. Exclusion criteria were as follows: the neonate was transferred from another institution after 72 hours of life; the neonate died before blood collection; major congenital anomalies; inborn errors of metabolism; congenital infections (STORCH screen); HIV-positive mothers; multiple pregnancies; and mothers with autoimmune disease. Blood was collected from neonates within the first 72 hours of life, and a second sample was collected at 28 days of life from those who remained hospitalized. VEGF, sFlt-1 and VEGF/PlGF levels were measured using the ELISA method. Results: A total of 88 neonates were included (37 born to mothers with and 51 without PE), with mean gestational age of 29.12 ± 2.96 weeks and birth weight of 1223.80 ± 417.48 g. VEGF was lower in the group with PE [32.45 (6.36-85.75) vs. 82.38 (35-130.03) pg/mL] (p = 0.001), and sFlt-1 was higher in the group with PE [1338.57 (418.8-3472.24) vs. 318.13 (182.03-453.66) pg/mL] (p < 0.001). In the multivariate analysis, VEGF was 80% lower and sFlt-1 was 13.48 times higher in the group with PE. sFlt-1 concentration was higher in neonates small for gestational age (SGA) than in those appropriate for gestational age (AGA) [1044.94 (290.64-3472.24) vs. 372.67 (236.75-860.14) pg/mL] (p = 0.013). In the group with PE, VEGF levels increased [≠151.71 (76.55-226.86); p < 0.001) between the first and second collection (at 28 days), while sFlt-1 levels decreased [≠1941.44 (2757.01-1125.87); p < 0.001] between the two measurements. Median VEGF/PlGF levels were significantly higher among infants born to mothers with PE (20.69 pg/mL [12.79-52.86] vs. 12.19 pg/mL [0.03-21.58], p = 0.003). These findings held on multivariate analysis, with VEGF/PlGF levels 1.05-fold higher in the PE group. VEGF/PlGF levels were inversely proportional to birth weight (p < 0.001, r = - 0.418). There were no between-group differences in blood samples collected at age 28 days. Conclusion: Higher sFlt-1 and VEGF/PlGF and lower VEGF levels in the group with PE, as well as higher sFlt-1 levels in SGA neonates, reflect a predominance of antiangiogenic mechanisms in PE and growth restriction. The VEGF/PlGF levels also affected the weight at birth, with VEGF/PlGF levels inversely proportional to birth weight. This antiangiogenic state of PE shows a trend toward normalization within 28 days of life.

OBJETIVO: Avaliar o comportamento alimentar de recém-nascidos (RN) pequenos (PIG) e grandes (GIG) para a idade gestacional através de questionário específico e comparar com RN adequados para a idade gestacional (AIG). METODOLOGIA: Estudo de coorte prospectivo, cuja primeira fase consistiu na realização de uma entrevista para coleta de dados da mãe da gestação e do parto, bem como de dados socioeconômicos, com mães que tiveram seus filhos a termo no Hospital de Clínicas de Porto Alegre. Na segunda fase do estudo foi aplicado o questionário Baby Eating Behaviour Questionnaire (BEBQ) através de contato por telefone, com 1 mês do nascimento. RESULTADOS: Foram avaliados 126 RN (43 AIG, 43 PIG e 40 GIG). As análises não demonstraram diferenças significativas nos principais dados demográficos e perinatais em relação aos diferentes grupos de estudo. No entanto, foi observada uma maior escolaridade em mães de RN PIG (p=0,004) e uma menor prevalência de aleitamento materno exclusivo até a alta hospitalar em RN GIG (p=0,002). A análise de variância não encontrou diferença significativa entre os grupos em relação aos domínios do BEBQ, mesmo quando corrigido por sexo do RN. CONCLUSÃO: O estudo demonstrou que alterações do comportamento alimentar ainda não estão presentes com 1 mês de vida, sugerindo que não são inatas, e sim desenvolvidas com o passar do tempo. O estudo tem como limitação as avaliações do crescimento baseadas em registros de terceiros. / OBJECTIVE: To evaluate feeding behavior of infants born small (SGA) and large (LGA) for gestational age using a questionnaire, and compare them with infants born adequate for gestational age (AGA). METHODS: Prospective cohort study was carried out in which the first phase consisted of an interview about gestation and delivery, as well as socioeconomic data, with mothers who had their babies born at term in the Hospital de Clínicas de Porto Alegre. In the second phase of the study, the Baby Eating Questionnaire (BEBQ) was applied through telephone interview 1 month of birth. RESULTS: 126 infants (43 AGA, 43 SGA and 40 LGA) with a mean gestational age of 39.4 weeks were assessed. The analyses did not show significant differences in the main demographic and perinatal data between the different study groups. However, a higher level of schooling was observed in mothers of SGA infants (p = 0.004) and a lower prevalence of exclusive breastfeeding in the LGA (p = 0.002). The analysis of variance found no significant difference between the groups in any of the BEBQ domains, even when corrected for the sex of the baby. CONCLUSION: This study demonstrated that changes in feeding behavior are not yet present at 1 month of age, suggesting that they are not innate, but developed over time. The study is limited to growth assessments based on third-party records.

Introdução: Sabe-se que os fatores angiogênicos e antiangiogênicos encontram-se alterados nas gestações com pré-eclâmpsia (PE), mas se desconhece seu comportamento nestes recém-nascidos (RNs). Objetivo: Dosagem do vascular endothelial growth factor (VEGF), soluble fms-like tyrosine kinase-1 (sFtl-1) e heterodímero vascular endothelial growth factor/placental growth factor (VEGF/PlGF) em pré-termos filhos de mães com PE. Métodos: Incluídos: RNs com peso de nascimento < 2.000 g e idade gestacional (IG) ≤ 34 semanas, divididos em dois grupos: filhos de mães com e sem PE. Excluídos: RNs transferidos de outra instituição com mais de 72 horas de vida, óbito antes da coleta dos exames, malformação congênita maior, erros inatos de metabolismo, gestações múltiplas, mães com infecção do grupo sífilis, toxoplasmose, rubéola, citomegalovírus, herpes (STORCH) ou vírus da imunodeficiência humana (HIV) e doença autoimune. Coletado sangue nas primeiras 72 horas de vida, e nos RNs que permaneceram internados, foi realizada uma segunda coleta com 28 dias. Foi utilizado método ELISA para a dosagem do VEGF, sFlt-1 e VEGF/PlGF. Resultados: Incluídos: 88 pacientes (37 filhos de mães com PE, 51 sem PE) com IG de 29,12 ± 2,96 semanas e peso de nascimento de 1223,80 ± 417,48 g. O VEGF foi menor no grupo com PE [32,45 (6,36-85,75) x 82,38 (35-130,03) pg/mL], p = 0,001 e o sFlt-1 foi maior no grupo com PE [1338,57 (418,8-3472,24) x 318,13 (182,03-453,66) pg/mL], p < 0,001. Na análise multivariada, o VEGF foi 80% menor e sFlt-1 13,48 vezes maior no grupo com PE. O sFlt-1 foi maior nos RNs pequenos para idade gestacional (PIG) do que nos adequados para idade gestacional (AIG) [1044,94 (290,64-3472,24) x 372,67 (236,75-860,14) pg/mL], p = 0,013. No grupo com PE, houve um aumento [≠ 151,71 (76,55-226,86); p < 0,001] entre as dosagens do VEGF entre a primeira e a segunda coleta com 28 dias, já o sFlt-1 diminuiu [≠ 1941,44 (2757,01-1125,87); p < 0,001] entre as duas dosagens. O VEGF/PlGF foi maior nos filhos de mães com PE [20,69 pg/mL (12,79-52,86) x 12,19 pg/mL (0,03 -21,58)], p = 0,003. Esses achados mantiveram-se na análise multivariada, com o VEGF/PlGF 1,05 vezes maior nos filhos de mães com PE. Os níveis de VEGF/PlGF foram inversamente proporcionais ao peso de nascimento, com p < 0,001 e r = - 0,418. Na segunda coleta com 28 dias de vida não houve diferença entre os dois grupos. Conclusão: Os maiores níveis de sFlt-1 e VEGF/PlGF e menores níveis de VEGF no grupo com PE, assim como maiores concentrações de sFlt-1 nos PIG refletem uma predominância dos mecanismos antiangiogênicos na PE e na restrição de crescimento. Os níveis de VEGF/PlGF também foram relacionados ao peso de nascimento, sendo inversamente proporcionais. O estado antiangiogênico da PE tende à normalização com 28 dias de vida. / Background: It is known that angiogenic and antiangiogenic factors are altered in pregnant women with preeclampsia (PE), but the pattern of expression of these factors in their newborn infants remains unknown. Objective: To measure vascular endothelial growth factor (VEGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and vascular endothelial growth factor/placental growth factor (VEGF/PlGF) heterodimer levels in preterm neonates born to mothers with PE. Methods: Neonates with birth weight < 2,000 g and gestational age ≤ 34 weeks were included and divided into two groups: born to mothers with and without PE. Exclusion criteria were as follows: the neonate was transferred from another institution after 72 hours of life; the neonate died before blood collection; major congenital anomalies; inborn errors of metabolism; congenital infections (STORCH screen); HIV-positive mothers; multiple pregnancies; and mothers with autoimmune disease. Blood was collected from neonates within the first 72 hours of life, and a second sample was collected at 28 days of life from those who remained hospitalized. VEGF, sFlt-1 and VEGF/PlGF levels were measured using the ELISA method. Results: A total of 88 neonates were included (37 born to mothers with and 51 without PE), with mean gestational age of 29.12 ± 2.96 weeks and birth weight of 1223.80 ± 417.48 g. VEGF was lower in the group with PE [32.45 (6.36-85.75) vs. 82.38 (35-130.03) pg/mL] (p = 0.001), and sFlt-1 was higher in the group with PE [1338.57 (418.8-3472.24) vs. 318.13 (182.03-453.66) pg/mL] (p < 0.001). In the multivariate analysis, VEGF was 80% lower and sFlt-1 was 13.48 times higher in the group with PE. sFlt-1 concentration was higher in neonates small for gestational age (SGA) than in those appropriate for gestational age (AGA) [1044.94 (290.64-3472.24) vs. 372.67 (236.75-860.14) pg/mL] (p = 0.013). In the group with PE, VEGF levels increased [≠151.71 (76.55-226.86); p < 0.001) between the first and second collection (at 28 days), while sFlt-1 levels decreased [≠1941.44 (2757.01-1125.87); p < 0.001] between the two measurements. Median VEGF/PlGF levels were significantly higher among infants born to mothers with PE (20.69 pg/mL [12.79-52.86] vs. 12.19 pg/mL [0.03-21.58], p = 0.003). These findings held on multivariate analysis, with VEGF/PlGF levels 1.05-fold higher in the PE group. VEGF/PlGF levels were inversely proportional to birth weight (p < 0.001, r = - 0.418). There were no between-group differences in blood samples collected at age 28 days. Conclusion: Higher sFlt-1 and VEGF/PlGF and lower VEGF levels in the group with PE, as well as higher sFlt-1 levels in SGA neonates, reflect a predominance of antiangiogenic mechanisms in PE and growth restriction. The VEGF/PlGF levels also affected the weight at birth, with VEGF/PlGF levels inversely proportional to birth weight. This antiangiogenic state of PE shows a trend toward normalization within 28 days of life.

Introdução: Sabe-se que os fatores angiogênicos e antiangiogênicos encontram-se alterados nas gestações com pré-eclâmpsia (PE), mas se desconhece seu comportamento nestes recém-nascidos (RNs). Objetivo: Dosagem do vascular endothelial growth factor (VEGF), soluble fms-like tyrosine kinase-1 (sFtl-1) e heterodímero vascular endothelial growth factor/placental growth factor (VEGF/PlGF) em pré-termos filhos de mães com PE. Métodos: Incluídos: RNs com peso de nascimento < 2.000 g e idade gestacional (IG) ≤ 34 semanas, divididos em dois grupos: filhos de mães com e sem PE. Excluídos: RNs transferidos de outra instituição com mais de 72 horas de vida, óbito antes da coleta dos exames, malformação congênita maior, erros inatos de metabolismo, gestações múltiplas, mães com infecção do grupo sífilis, toxoplasmose, rubéola, citomegalovírus, herpes (STORCH) ou vírus da imunodeficiência humana (HIV) e doença autoimune. Coletado sangue nas primeiras 72 horas de vida, e nos RNs que permaneceram internados, foi realizada uma segunda coleta com 28 dias. Foi utilizado método ELISA para a dosagem do VEGF, sFlt-1 e VEGF/PlGF. Resultados: Incluídos: 88 pacientes (37 filhos de mães com PE, 51 sem PE) com IG de 29,12 ± 2,96 semanas e peso de nascimento de 1223,80 ± 417,48 g. O VEGF foi menor no grupo com PE [32,45 (6,36-85,75) x 82,38 (35-130,03) pg/mL], p = 0,001 e o sFlt-1 foi maior no grupo com PE [1338,57 (418,8-3472,24) x 318,13 (182,03-453,66) pg/mL], p < 0,001. Na análise multivariada, o VEGF foi 80% menor e sFlt-1 13,48 vezes maior no grupo com PE. O sFlt-1 foi maior nos RNs pequenos para idade gestacional (PIG) do que nos adequados para idade gestacional (AIG) [1044,94 (290,64-3472,24) x 372,67 (236,75-860,14) pg/mL], p = 0,013. No grupo com PE, houve um aumento [≠ 151,71 (76,55-226,86); p < 0,001] entre as dosagens do VEGF entre a primeira e a segunda coleta com 28 dias, já o sFlt-1 diminuiu [≠ 1941,44 (2757,01-1125,87); p < 0,001] entre as duas dosagens. O VEGF/PlGF foi maior nos filhos de mães com PE [20,69 pg/mL (12,79-52,86) x 12,19 pg/mL (0,03 -21,58)], p = 0,003. Esses achados mantiveram-se na análise multivariada, com o VEGF/PlGF 1,05 vezes maior nos filhos de mães com PE. Os níveis de VEGF/PlGF foram inversamente proporcionais ao peso de nascimento, com p < 0,001 e r = - 0,418. Na segunda coleta com 28 dias de vida não houve diferença entre os dois grupos. Conclusão: Os maiores níveis de sFlt-1 e VEGF/PlGF e menores níveis de VEGF no grupo com PE, assim como maiores concentrações de sFlt-1 nos PIG refletem uma predominância dos mecanismos antiangiogênicos na PE e na restrição de crescimento. Os níveis de VEGF/PlGF também foram relacionados ao peso de nascimento, sendo inversamente proporcionais. O estado antiangiogênico da PE tende à normalização com 28 dias de vida. / Background: It is known that angiogenic and antiangiogenic factors are altered in pregnant women with preeclampsia (PE), but the pattern of expression of these factors in their newborn infants remains unknown. Objective: To measure vascular endothelial growth factor (VEGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and vascular endothelial growth factor/placental growth factor (VEGF/PlGF) heterodimer levels in preterm neonates born to mothers with PE. Methods: Neonates with birth weight < 2,000 g and gestational age ≤ 34 weeks were included and divided into two groups: born to mothers with and without PE. Exclusion criteria were as follows: the neonate was transferred from another institution after 72 hours of life; the neonate died before blood collection; major congenital anomalies; inborn errors of metabolism; congenital infections (STORCH screen); HIV-positive mothers; multiple pregnancies; and mothers with autoimmune disease. Blood was collected from neonates within the first 72 hours of life, and a second sample was collected at 28 days of life from those who remained hospitalized. VEGF, sFlt-1 and VEGF/PlGF levels were measured using the ELISA method. Results: A total of 88 neonates were included (37 born to mothers with and 51 without PE), with mean gestational age of 29.12 ± 2.96 weeks and birth weight of 1223.80 ± 417.48 g. VEGF was lower in the group with PE [32.45 (6.36-85.75) vs. 82.38 (35-130.03) pg/mL] (p = 0.001), and sFlt-1 was higher in the group with PE [1338.57 (418.8-3472.24) vs. 318.13 (182.03-453.66) pg/mL] (p < 0.001). In the multivariate analysis, VEGF was 80% lower and sFlt-1 was 13.48 times higher in the group with PE. sFlt-1 concentration was higher in neonates small for gestational age (SGA) than in those appropriate for gestational age (AGA) [1044.94 (290.64-3472.24) vs. 372.67 (236.75-860.14) pg/mL] (p = 0.013). In the group with PE, VEGF levels increased [≠151.71 (76.55-226.86); p < 0.001) between the first and second collection (at 28 days), while sFlt-1 levels decreased [≠1941.44 (2757.01-1125.87); p < 0.001] between the two measurements. Median VEGF/PlGF levels were significantly higher among infants born to mothers with PE (20.69 pg/mL [12.79-52.86] vs. 12.19 pg/mL [0.03-21.58], p = 0.003). These findings held on multivariate analysis, with VEGF/PlGF levels 1.05-fold higher in the PE group. VEGF/PlGF levels were inversely proportional to birth weight (p < 0.001, r = - 0.418). There were no between-group differences in blood samples collected at age 28 days. Conclusion: Higher sFlt-1 and VEGF/PlGF and lower VEGF levels in the group with PE, as well as higher sFlt-1 levels in SGA neonates, reflect a predominance of antiangiogenic mechanisms in PE and growth restriction. The VEGF/PlGF levels also affected the weight at birth, with VEGF/PlGF levels inversely proportional to birth weight. This antiangiogenic state of PE shows a trend toward normalization within 28 days of life.

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.

La restriction de croissance intra-utérine (RCIU) est une conséquence immédiate d’un environnement utérin défavorable qui prédispose les individus atteints à de plus grands risques de développer des maladies cardiométaboliques une fois adulte. L’environnement fœtal s’ajoute ainsi à l’hérédité, au sexe et au mode de vie comme facteur déterminant de la santé cardiométabolique. Afin de mieux comprendre les différents aspects de cette prédisposition, notre laboratoire a développé un modèle animal de RCIU asymétrique recréant une diminution de la perfusion placentaire. La caractérisation des animaux a mis en évidence des différences dans la physiologie cardiovasculaire des individus adultes avec des dissemblances selon le sexe, ainsi qu’une différence dans l’expression de plusieurs gènes impliqués dans le métabolisme lipidique chez le fœtus. A partir de ces données, nous émettons l’hypothèse que le cœur fœtal RCIU subit une reprogrammation métabolique, conséquence du stress causé par l’environnement fœtal défavorable. Nous nous attendons aussi à une régulation différente du métabolisme entre les mâles et les femelles. Pour répondre à cette hypothèse, nous avons tout d’abord déterminé la contribution du métabolisme lipidique dans les cœurs fœtaux RCIU ainsi que sa régulation. Ensuite, nous avons approfondi les conséquences d’un métabolisme lipidique élevé dans les cœurs fœtaux RCIU. Le sexe des animaux a été pris en compte dans nos travaux. L’ensemble de ces travaux démontrent une plus grande utilisation du métabolisme lipidique chez les fœtus RCIU, impliquant une activation du récepteur nucléaire PPARα et du coactivateur PGC1a par une abondance d’acides gras (AG) à longue chaîne dans les cœurs fœtaux RCIU. L’activation de PPARα entraine une augmentation de l’expression de nombreux gènes impliqués dans l’oxydation des AG et de la biogenèse mitochondriale. Les mitochondries des cœurs fœtaux RCIU femelles montrent de plus grandes capacités de production d’ATP, comparées aux femelles témoins, mais aucune différence n’a été montrée chez les mâles. Un tel dysmorphisme a également été observé dans l’augmentation des capacités d’oxydation des AG à très longues chaînes chez les femelles RCIU, mais pas chez les mâles. L’augmentation de l’expression de Pdk4 dans les cœurs fœtaux RCIU confirme le fort métabolisme lipidique et suggère une abondance d’acétyl-CoA, molécule intermédiaire à plusieurs voies métaboliques, dont la production de corps cétoniques. Nous avons montré une synthèse intracardiaque de corps cétoniques chez les fœtus RCIU, sans élévation de la cétolyse, causant une accumulation d’acétoacétate et de β-hydroxybutyrate (bHB). Enfin, l’exploration des rôles signalétiques du bHB nous a permis d’observer une régulation positive de ce corps cétonique sur le métabolisme lipidique, par une activation de PPARα. En conclusion, ce projet de thèse a contribué à mieux comprendre les mécanismes d’adaptation métabolique des cœurs fœtaux à une RCIU causée par une diminution de la perfusion placentaire en fonction du sexe. Notre travail ouvre également la voie à de nouvelles avenues de recherche sur le rôle signalétique des corps cétoniques et des AG à longue chaîne dans la programmation des maladies cardiométaboliques. / An unfavorable womb environment often leads to intrauterine growth restriction (IUGR), which is known to increase the likelihood of developing cardiometabolic diseases later in life. The fetal environment is thus added to other factors such as heredity, sex and lifestyle that have an impact on cardiometabolic health. To investigate IUGR predisposed condition, our laboratory has developed an animal model of asymmetric IUGR by decreasing placental perfusion. Our findings using this animal model have highlighted sex-dependent differences in the cardiovascular physiology of IUGR adults, and specific changes in the expression of key genes involved in lipid metabolism in IUGR fetuses. Therefore, we hypothesize that the IUGR fetal heart undergoes a metabolic remodeling in response to the stress caused by the unfavorable uterine environment. We also expect selective metabolic changes in males and females. To verify this hypothesis, we addressed the contribution and regulation of lipid metabolism in IUGR fetal hearts. We also thoroughly investigated the consequences of a high lipid metabolism in IUGR fetal hearts. Changes between males and females were also considered. This study shows an increased use of lipid metabolism in IUGR fetuses, which involves the transcriptional activation of the nuclear receptor PPARα and the coactivator PGC1 in response to accumulated levels of specific long-chain fatty acids (FA) in IUGR fetal hearts. Activation of PPARα lead to an increase in the expression of critical genes involved in the oxidation of FAs and mitochondrial biogenesis. Mitochondrial respiration analysis demonstrated a greater ATP production capability in female IUGR fetal hearts compared to control females, a finding not observed in males. The increased expression of Pdk4 in IUGR fetal hearts attests such a strong lipid metabolism and suggests an abundance of acetyl-CoA, an intermediate molecule to several metabolic pathways, including the production of ketone bodies. Indeed, our results indicate an increased intracardiac synthesis of ketone bodies in IUGR fetuses without inducing ketolytic genes, resulting in significant accumulation of acetoacetate and β-hydroxybutyrate (bHB). Moreover, we provide evidence of a signaling role of bHB with a positive regulation of lipid metabolism through the transcriptional activation of PPARα. In conclusion, this thesis contributes to a better understanding of the mechanisms involved in the metabolic adaptation of fetal hearts to IUGR and highlights selective changes according to sex. Our study also paves the way for new research avenues on the signaling role of ketone bodies and long-chain FAs on the programming of cardiometabolic diseases.

As gestações gemelares monocoriônicas e diamnióticas (MCDA) apresentam maior risco de restrição de crescimento fetal (RCF) e complicações perinatais. O objetivo deste estudo foi avaliar a morbidade e mortalidade perinatal em gestações gemelares MCDA: na presença de RCF e dopplervelocimetria de artéria umbilical normal e anormal; nos diferentes padrões de dopplervelocimetria de artéria umbilical (doppler normal, índice de pulsatilidade aumentado, fluxo diastólico intermitente de artéria umbilical, diástole zero e diástole reversa) e na presença de RCF seletiva e não seletiva. Estudo retrospectivo, com levantamento dos casos no período entre 2004 e 2011, no Setor de Gestações Múltiplas da Clínica Obstétrica do HCFMUSP. Desta forma, foram inseridas 48 gestações gemelares, com 60 fetos abaixo do percentil 10 de uma curva específica para gêmeos. Casos que apresentaram malformações fetais (n=36) ou síndrome da transfusão fetofetal (n=43) não foram incluídos no estudo. O grupo com RCF e dopplervelocimetria anormal apresentou menor média de idade gestacional no parto (33,39 versus 35,48, p <0,001), menor média de peso ao nascimento (1137,12 gramas versus 1675,77 gramas, p < 0,001), maior frequência de internação em Unidade de terapia intensiva (UTI) neonatal (69,23% versus 19,23%, p = 0,0003), maior frequência de doença respiratória (73,08 versus 34,62, p = 0,005) e maior frequência de óbito intrauterino e neonatal (p = 0,025). Na avaliação dos diferentes padrões de dopplervelocimetria da artéria umbilical (normal, índice de pulsatilidade aumentado, fluxo diastólico intermitente, diástole zero e diástole reversa), os grupos diferiram em relação à média da idade gestacional no parto (35,48; 34,22; 33,33; 33,15 e 32,45 semanas, p < 0,001), frequência de internação em UTI neonatal (19,23; 50,00; 50,00; 85,71 e 100,00%, p < 0,001) e desfecho com alta hospitalar (96,15; 100,00; 83,33; 71,43 e 25,00%, p < 0,001). O grupo com diástole reversa apresentou os piores resultados perinatais. Na avaliação da RCF seletiva, não foi observada diferença significativa em relação à idade gestacional no parto (33,4 versus 33,4, p = 0,953), mas houve maior necessidade de intubação orotraqueal (62,5% versus 32,3%, p = 0,001) e ventilação mecânica (75,0% versus 41,2%, p = 0,0006) em relação ao grupo de RCF não seletiva. No grupo RCF seletiva houve maior número de casos de dopplervelocimetria de artéria umbilical com índice de pulsatilidade aumentada, fluxo intermitente, diástole zero e reversa (p = 0,005). Como conclusão o estudo demonstrou maior morbidade e mortalidade perinatal no grupo com dopplervelocimetria anormal com diferença significativa em relação aos padrões distintos de dopplervelocimetria e piores resultados na presença de diástole reversa. O grupo de RCF seletiva apresentou maior frequência de anormalidades na dopplervelocimetria de artéria umbilical e morbidade neonatal em relação ao grupo com RCF não seletiva / Monochorionic diamniotic (MCDA) twin pregnancies have and increased risk for intrauterine growth restriction (IUGR) and perinatal complications. The aim of this study is to evaluate perinatal morbidity and mortality in MCDA twin pregnancies: in the presence of IUGR with normal and abnormal umbilical artery dopplervelocimetry; in different umbilical artery flow patterns (normal dopplervelocimetry, increased pulsatility index, intermittent flow pattern, absent end diastolic flow and reversed end diastolic flow) and in the presence of selective and non-selective IUGR. This was a retrospective study in the Multiple Pregnancy Unit at the Obstetric Clinic of HCFMUSP, between 2004 and 2011. The study included 48 twin pregnancies, where 60 fetuses weighted less than the 10th percentile according to twins charts. Cases with fetal malformation (n=36) or twin to twin transfusion syndrome (n=43) were not included in the study. The group with IUGR and abnormal umbilical artery Doppler presented lower mean gestational age at delivery (33.39 versus 35.48, p <0.001), lower mean birthweight (1137.12 g versus 1675.77 g, p < 0.001), higher need of neonatal intensive care unit (NICU, 69.23% versus 19.23%, p = 0.0003), higher frequency of respiratory disease (73.08 versus 34.62, p = 0.005) and higher incidence of intrauterine and neonatal death (p = 0.025). In the different umbilical artery flow patterns (normal dopplervelocimetry, increased pulsatility index, intermittent flow pattern, absent end diastolic flow and reversed end diastolic flow) the group differ in relation to gestational age at delivery (35.48; 34.22; 33.33; 33.15 and 32.45 weeks; p < 0.001), need of NICU (19.23; 50.00; 50.00; 85.71 and 100,00%; p < 0.001) and alive at hospital discharge (96.15; 100,00; 83.33; 71.43 and 25,00%; p < 0.001). The group with reversed and diastolic flow presented the worse perinatal outcome. In the selective and non-selective IUGR groups, no difference was observed in relation to gestational age at delivery (33.4 versus 33.4 weeks, p = 0.953), however there was higher need for orotracheal intubation (62.5% versus 32.3%, p = 0.001) and mechanical ventilation (75.0% versus 41.2%, p = 0.0006) in the selective IUGR group. Abnormal umbilical artery Doppler such as increased pulsatility index, intermittent blood flow, absent and reversed flow were more frequent in the selective IUGR group (p = 0.005). As conclusion, the study demonstrated higher perinatal morbidity and mortality in the IUGR group with abnormal umbilical artery Doppler with significant difference in relation to Doppler patterns and the worse outcome was related to reversed diastolic flow pattern. The selective IUGR group presents higher frequency of abnormal umbilical artery dopplervelocimetry and neonatal morbidity compared to non- selective IUGR group

As gestações gemelares monocoriônicas e diamnióticas (MCDA) apresentam maior risco de restrição de crescimento fetal (RCF) e complicações perinatais. O objetivo deste estudo foi avaliar a morbidade e mortalidade perinatal em gestações gemelares MCDA: na presença de RCF e dopplervelocimetria de artéria umbilical normal e anormal; nos diferentes padrões de dopplervelocimetria de artéria umbilical (doppler normal, índice de pulsatilidade aumentado, fluxo diastólico intermitente de artéria umbilical, diástole zero e diástole reversa) e na presença de RCF seletiva e não seletiva. Estudo retrospectivo, com levantamento dos casos no período entre 2004 e 2011, no Setor de Gestações Múltiplas da Clínica Obstétrica do HCFMUSP. Desta forma, foram inseridas 48 gestações gemelares, com 60 fetos abaixo do percentil 10 de uma curva específica para gêmeos. Casos que apresentaram malformações fetais (n=36) ou síndrome da transfusão fetofetal (n=43) não foram incluídos no estudo. O grupo com RCF e dopplervelocimetria anormal apresentou menor média de idade gestacional no parto (33,39 versus 35,48, p <0,001), menor média de peso ao nascimento (1137,12 gramas versus 1675,77 gramas, p < 0,001), maior frequência de internação em Unidade de terapia intensiva (UTI) neonatal (69,23% versus 19,23%, p = 0,0003), maior frequência de doença respiratória (73,08 versus 34,62, p = 0,005) e maior frequência de óbito intrauterino e neonatal (p = 0,025). Na avaliação dos diferentes padrões de dopplervelocimetria da artéria umbilical (normal, índice de pulsatilidade aumentado, fluxo diastólico intermitente, diástole zero e diástole reversa), os grupos diferiram em relação à média da idade gestacional no parto (35,48; 34,22; 33,33; 33,15 e 32,45 semanas, p < 0,001), frequência de internação em UTI neonatal (19,23; 50,00; 50,00; 85,71 e 100,00%, p < 0,001) e desfecho com alta hospitalar (96,15; 100,00; 83,33; 71,43 e 25,00%, p < 0,001). O grupo com diástole reversa apresentou os piores resultados perinatais. Na avaliação da RCF seletiva, não foi observada diferença significativa em relação à idade gestacional no parto (33,4 versus 33,4, p = 0,953), mas houve maior necessidade de intubação orotraqueal (62,5% versus 32,3%, p = 0,001) e ventilação mecânica (75,0% versus 41,2%, p = 0,0006) em relação ao grupo de RCF não seletiva. No grupo RCF seletiva houve maior número de casos de dopplervelocimetria de artéria umbilical com índice de pulsatilidade aumentada, fluxo intermitente, diástole zero e reversa (p = 0,005). Como conclusão o estudo demonstrou maior morbidade e mortalidade perinatal no grupo com dopplervelocimetria anormal com diferença significativa em relação aos padrões distintos de dopplervelocimetria e piores resultados na presença de diástole reversa. O grupo de RCF seletiva apresentou maior frequência de anormalidades na dopplervelocimetria de artéria umbilical e morbidade neonatal em relação ao grupo com RCF não seletiva / Monochorionic diamniotic (MCDA) twin pregnancies have and increased risk for intrauterine growth restriction (IUGR) and perinatal complications. The aim of this study is to evaluate perinatal morbidity and mortality in MCDA twin pregnancies: in the presence of IUGR with normal and abnormal umbilical artery dopplervelocimetry; in different umbilical artery flow patterns (normal dopplervelocimetry, increased pulsatility index, intermittent flow pattern, absent end diastolic flow and reversed end diastolic flow) and in the presence of selective and non-selective IUGR. This was a retrospective study in the Multiple Pregnancy Unit at the Obstetric Clinic of HCFMUSP, between 2004 and 2011. The study included 48 twin pregnancies, where 60 fetuses weighted less than the 10th percentile according to twins charts. Cases with fetal malformation (n=36) or twin to twin transfusion syndrome (n=43) were not included in the study. The group with IUGR and abnormal umbilical artery Doppler presented lower mean gestational age at delivery (33.39 versus 35.48, p <0.001), lower mean birthweight (1137.12 g versus 1675.77 g, p < 0.001), higher need of neonatal intensive care unit (NICU, 69.23% versus 19.23%, p = 0.0003), higher frequency of respiratory disease (73.08 versus 34.62, p = 0.005) and higher incidence of intrauterine and neonatal death (p = 0.025). In the different umbilical artery flow patterns (normal dopplervelocimetry, increased pulsatility index, intermittent flow pattern, absent end diastolic flow and reversed end diastolic flow) the group differ in relation to gestational age at delivery (35.48; 34.22; 33.33; 33.15 and 32.45 weeks; p < 0.001), need of NICU (19.23; 50.00; 50.00; 85.71 and 100,00%; p < 0.001) and alive at hospital discharge (96.15; 100,00; 83.33; 71.43 and 25,00%; p < 0.001). The group with reversed and diastolic flow presented the worse perinatal outcome. In the selective and non-selective IUGR groups, no difference was observed in relation to gestational age at delivery (33.4 versus 33.4 weeks, p = 0.953), however there was higher need for orotracheal intubation (62.5% versus 32.3%, p = 0.001) and mechanical ventilation (75.0% versus 41.2%, p = 0.0006) in the selective IUGR group. Abnormal umbilical artery Doppler such as increased pulsatility index, intermittent blood flow, absent and reversed flow were more frequent in the selective IUGR group (p = 0.005). As conclusion, the study demonstrated higher perinatal morbidity and mortality in the IUGR group with abnormal umbilical artery Doppler with significant difference in relation to Doppler patterns and the worse outcome was related to reversed diastolic flow pattern. The selective IUGR group presents higher frequency of abnormal umbilical artery dopplervelocimetry and neonatal morbidity compared to non- selective IUGR group