The Experts below are selected from a list of 18573 Experts worldwide ranked by ideXlab platform

Maurizio Mandala - One of the best experts on this subject based on the ideXlab platform.

  • pregnancy augments g protein estrogen receptor gper induced vasodilation in rat uterine arteries via the nitric oxide cgmp signaling pathway
    PLOS ONE, 2015
    Co-Authors: Teresa Tropea, Ernestina Marianna De Francesco, Damiano Cosimo Rigiracciolo, Marcello Maggiolini, Mark Wareing, George Osol, Maurizio Mandala
    Abstract:

    BACKGROUND: The regulation of vascular tone in the uterine circulation is a key determinant of appropriate uteroplacental blood perfusion and successful pregnancy outcome. Estrogens, which increase in the maternal circulation throughout pregnancy, can exert acute vasodilatory actions. Recently a third estrogen receptor named GPER (G protein-coupled estrogen receptor) was identified and, although several studies have shown vasodilatory effects in several vascular beds, nothing is known about its role in the uterine vasculature. AIM: The aim of this study was to determine the function of GPER in uterine arteries mainly during pregnancy. Uterine arteries were isolated from nonpregnant and pregnant rats. METHODS: Vessels were contracted with phenylephrine and then incubated with incremental doses (10-12-10-5 M) of the selective GPER agonist G1. RESULTS: G1 induced a dose-dependent vasodilation which was: 1) significantly increased in pregnancy, 2) endothelium-dependent, 3) primarily mediated by NO/cGMP pathway and 4) unaffected by BKca channel inhibition. CONCLUSION: This is the first study to show the potential importance of GPER signaling in reducing uterine vascular tone during pregnancy. GPER may therefore play a previously unrecognized role in the regulation of uteroplacental blood flow and normal Fetus Growth.

Teresa Tropea - One of the best experts on this subject based on the ideXlab platform.

  • pregnancy augments g protein estrogen receptor gper induced vasodilation in rat uterine arteries via the nitric oxide cgmp signaling pathway
    PLOS ONE, 2015
    Co-Authors: Teresa Tropea, Ernestina Marianna De Francesco, Damiano Cosimo Rigiracciolo, Marcello Maggiolini, Mark Wareing, George Osol, Maurizio Mandala
    Abstract:

    BACKGROUND: The regulation of vascular tone in the uterine circulation is a key determinant of appropriate uteroplacental blood perfusion and successful pregnancy outcome. Estrogens, which increase in the maternal circulation throughout pregnancy, can exert acute vasodilatory actions. Recently a third estrogen receptor named GPER (G protein-coupled estrogen receptor) was identified and, although several studies have shown vasodilatory effects in several vascular beds, nothing is known about its role in the uterine vasculature. AIM: The aim of this study was to determine the function of GPER in uterine arteries mainly during pregnancy. Uterine arteries were isolated from nonpregnant and pregnant rats. METHODS: Vessels were contracted with phenylephrine and then incubated with incremental doses (10-12-10-5 M) of the selective GPER agonist G1. RESULTS: G1 induced a dose-dependent vasodilation which was: 1) significantly increased in pregnancy, 2) endothelium-dependent, 3) primarily mediated by NO/cGMP pathway and 4) unaffected by BKca channel inhibition. CONCLUSION: This is the first study to show the potential importance of GPER signaling in reducing uterine vascular tone during pregnancy. GPER may therefore play a previously unrecognized role in the regulation of uteroplacental blood flow and normal Fetus Growth.

Neil M Gude - One of the best experts on this subject based on the ideXlab platform.

  • Growth and function of the normal human placenta
    Thrombosis Research, 2004
    Co-Authors: Neil M Gude, Claire T Roberts, Bill Kalionis, Roger G King
    Abstract:

    The placenta is the highly specialised organ of pregnancy that supports the normal Growth and development of the Fetus. Growth and function of the placenta are precisely regulated and coordinated to ensure the exchange of nutrients and waste products between the maternal and fetal circulatory systems operates at maximal efficiency. The main functional units of the placenta are the chorionic villi within which fetal blood is separated by only three or four cell layers (placental membrane) from maternal blood in the surrounding intervillous space. After implantation, trophoblast cells proliferate and differentiate along two pathways described as villous and extravillous. Non-migratory, villous cytotrophoblast cells fuse to form the multinucleated syncytiotrophoblast, which forms the outer epithelial layer of the chorionic villi. It is at the terminal branches of the chorionic villi that the majority of fetal/maternal exchange occurs. Extravillous trophoblast cells migrate into the decidua and remodel uterine arteries. This facilitates blood flow to the placenta via dilated, compliant vessels, unresponsive to maternal vasomotor control. The placenta acts to provide oxygen and nutrients to the Fetus, whilst removing carbon dioxide and other waste products. It metabolises a number of substances and can release metabolic products into maternal and/or fetal circulations. The placenta can help to protect the Fetus against certain xenobiotic molecules, infections and maternal diseases. In addition, it releases hormones into both the maternal and fetal circulations to affect pregnancy, metabolism, fetal Growth, parturition and other functions. Many placental functional changes occur that accommodate the increasing metabolic demands of the developing Fetus throughout gestation.

  • Growth and function of the normal human placenta
    Thrombosis Research, 2004
    Co-Authors: Neil M Gude, Claire T Roberts, Bill Kalionis, Roger G King
    Abstract:

    The placenta is the highly specialised organ of pregnancy that supports the normal Growth and development of the Fetus. Growth and function of the placenta are precisely regulated and coordinated to ensure the exchange of nutrients and waste products between the maternal and fetal circulatory systems operates at maximal efficiency. The main functional units of the placenta are the chorionic villi within which fetal blood is separated by only three or four cell layers (placental membrane) from maternal blood in the surrounding intervillous space. After implantation, trophoblast cells proliferate and differentiate along two pathways described as villous and extravillous. Non-migratory, villous cytotrophoblast cells fuse to form the multinucleated syncytiotrophoblast, which forms the outer epithelial layer of the chorionic villi. It is at the terminal branches of the chorionic villi that the majority of fetal/maternal exchange occurs. Extravillous trophoblast cells migrate into the decidua and remodel uterine arteries. This facilitates blood flow to the placenta via dilated, compliant vessels, unresponsive to maternal vasomotor control. The placenta acts to provide oxygen and nutrients to the Fetus, whilst removing carbon dioxide and other waste products. It metabolises a number of substances and can release metabolic products into maternal and/or fetal circulations. The placenta can help to protect the Fetus against certain xenobiotic molecules, infections and maternal diseases. In addition, it releases hormones into both the maternal and fetal circulations to affect pregnancy, metabolism, fetal Growth, parturition and other functions. Many placental functional changes occur that accommodate the increasing metabolic demands of the developing Fetus throughout gestation.

Roger G King - One of the best experts on this subject based on the ideXlab platform.

  • Growth and function of the normal human placenta
    Thrombosis Research, 2004
    Co-Authors: Neil M Gude, Claire T Roberts, Bill Kalionis, Roger G King
    Abstract:

    The placenta is the highly specialised organ of pregnancy that supports the normal Growth and development of the Fetus. Growth and function of the placenta are precisely regulated and coordinated to ensure the exchange of nutrients and waste products between the maternal and fetal circulatory systems operates at maximal efficiency. The main functional units of the placenta are the chorionic villi within which fetal blood is separated by only three or four cell layers (placental membrane) from maternal blood in the surrounding intervillous space. After implantation, trophoblast cells proliferate and differentiate along two pathways described as villous and extravillous. Non-migratory, villous cytotrophoblast cells fuse to form the multinucleated syncytiotrophoblast, which forms the outer epithelial layer of the chorionic villi. It is at the terminal branches of the chorionic villi that the majority of fetal/maternal exchange occurs. Extravillous trophoblast cells migrate into the decidua and remodel uterine arteries. This facilitates blood flow to the placenta via dilated, compliant vessels, unresponsive to maternal vasomotor control. The placenta acts to provide oxygen and nutrients to the Fetus, whilst removing carbon dioxide and other waste products. It metabolises a number of substances and can release metabolic products into maternal and/or fetal circulations. The placenta can help to protect the Fetus against certain xenobiotic molecules, infections and maternal diseases. In addition, it releases hormones into both the maternal and fetal circulations to affect pregnancy, metabolism, fetal Growth, parturition and other functions. Many placental functional changes occur that accommodate the increasing metabolic demands of the developing Fetus throughout gestation.

  • Growth and function of the normal human placenta
    Thrombosis Research, 2004
    Co-Authors: Neil M Gude, Claire T Roberts, Bill Kalionis, Roger G King
    Abstract:

    The placenta is the highly specialised organ of pregnancy that supports the normal Growth and development of the Fetus. Growth and function of the placenta are precisely regulated and coordinated to ensure the exchange of nutrients and waste products between the maternal and fetal circulatory systems operates at maximal efficiency. The main functional units of the placenta are the chorionic villi within which fetal blood is separated by only three or four cell layers (placental membrane) from maternal blood in the surrounding intervillous space. After implantation, trophoblast cells proliferate and differentiate along two pathways described as villous and extravillous. Non-migratory, villous cytotrophoblast cells fuse to form the multinucleated syncytiotrophoblast, which forms the outer epithelial layer of the chorionic villi. It is at the terminal branches of the chorionic villi that the majority of fetal/maternal exchange occurs. Extravillous trophoblast cells migrate into the decidua and remodel uterine arteries. This facilitates blood flow to the placenta via dilated, compliant vessels, unresponsive to maternal vasomotor control. The placenta acts to provide oxygen and nutrients to the Fetus, whilst removing carbon dioxide and other waste products. It metabolises a number of substances and can release metabolic products into maternal and/or fetal circulations. The placenta can help to protect the Fetus against certain xenobiotic molecules, infections and maternal diseases. In addition, it releases hormones into both the maternal and fetal circulations to affect pregnancy, metabolism, fetal Growth, parturition and other functions. Many placental functional changes occur that accommodate the increasing metabolic demands of the developing Fetus throughout gestation.

Aw Welsh - One of the best experts on this subject based on the ideXlab platform.

  • fetal myocardial performance index in assessment and management of small for gestational age Fetus a cohort and nested case control study
    Ultrasound in Obstetrics & Gynecology, 2018
    Co-Authors: Aw Welsh, Amanda Henry, Jennifer Alphonse, Dominique Tynan
    Abstract:

    OBJECTIVE: To assess the clinical utility of the fetal myocardial performance index (MPI) in assessment and management of the small-for-gestational-age (SGA) Fetus/Growth-restricted Fetus (FGR). METHODS: This was a prospective cohort study in metropolitan Australia of patients referred in the period June 2012 to March 2015 to fetal medicine services at 24-38 weeks' gestation for suspected singleton SGA/FGR (estimated fetal weight (EFW) < 10th centile with or without abnormal umbilical artery (UA) Doppler) pregnancy. Patients had MPI assessed in addition to routine measures, and were followed through to birth. We compared MPI values against those of a local reference population and gestational age-matched controls, and assessed the correlation with perinatal outcome and other Doppler measures. RESULTS: Fifty-two cases were included, 38 diagnosed < 32 weeks and 14 diagnosed ≥ 32 weeks. None demonstrated significantly elevated left, right or delta MPI compared with the reference population or with gestational age-matched controls at the time of first MPI evaluation. There were no consistent longitudinal patterns in MPI that would suggest its clinical utility. The mean ± SD gestational age at delivery was 34.6 ± 3.8 weeks and birth weight was 1.7 ± 0.6 kg, and the median neonatal hospital admission time was 27 days, confirming a pathological cohort. There were no significant correlations between left, right or delta-MPI and perinatal outcome, although there were significant correlations between UA, middle cerebral artery (MCA) and ductus venosus (DV) Doppler and perinatal outcome (birth weight, gestational age at birth and length of neonatal hospital stay). Exploratory subgroup comparisons (EFW < 3rd vs 3rd -10th centile; early- vs late-onset; abnormal vs normal UA Doppler) found only minor differences in MPI, reaching statistical, but not clinical, significance, only in the EFW < 3rd vs 3rd -10th centile comparison. CONCLUSIONS: MPI did not demonstrate clinical utility in either triage or longitudinal follow-up of an SGA/FGR cohort presenting to fetal medicine services. Given that prior research suggesting its utility originates from single-center cohorts, while multicenter, large cohorts have suggested little utility or no additional utility if routine UA/MCA/DV Doppler is performed, publication bias may have affected previous reports. It seems unlikely that MPI has clinical utility in assessment and management of SGA/FGR Fetuses. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

  • Fetal myocardial performance index in assessment and management of small-for-gestational-age Fetus: a cohort and nested case–control study
    'Wiley', 2018
    Co-Authors: Henry A, Alphonse J, Tynan D, Aw Welsh
    Abstract:

    Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd. Objective: To assess the clinical utility of the fetal myocardial performance index (MPI) in assessment and management of the small-for-gestational-age (SGA) Fetus/Growth-restricted Fetus (FGR). Methods: This was a prospective cohort study in metropolitan Australia of patients referred in the period June 2012 to March 2015 to fetal medicine services at 24–38 weeks' gestation for suspected singleton SGA/FGR (estimated fetal weight (EFW) < 10th centile with or without abnormal umbilical artery (UA) Doppler) pregnancy. Patients had MPI assessed in addition to routine measures, and were followed through to birth. We compared MPI values against those of a local reference population and gestational age-matched controls, and assessed the correlation with perinatal outcome and other Doppler measures. Results: Fifty-two cases were included, 38 diagnosed < 32 weeks and 14 diagnosed ≥ 32 weeks. None demonstrated significantly elevated left, right or delta MPI compared with the reference population or with gestational age-matched controls at the time of first MPI evaluation. There were no consistent longitudinal patterns in MPI that would suggest its clinical utility. The mean ± SD gestational age at delivery was 34.6 ± 3.8 weeks and birth weight was 1.7 ± 0.6 kg, and the median neonatal hospital admission time was 27 days, confirming a pathological cohort. There were no significant correlations between left, right or delta-MPI and perinatal outcome, although there were significant correlations between UA, middle cerebral artery (MCA) and ductus venosus (DV) Doppler and perinatal outcome (birth weight, gestational age at birth and length of neonatal hospital stay). Exploratory subgroup comparisons (EFW < 3rd vs 3rd–10th centile; early- vs late-onset; abnormal vs normal UA Doppler) found only minor differences in MPI, reaching statistical, but not clinical, significance, only in the EFW < 3rd vs 3rd–10th centile comparison. Conclusions: MPI did not demonstrate clinical utility in either triage or longitudinal follow-up of an SGA/FGR cohort presenting to fetal medicine services. Given that prior research suggesting its utility originates from single-center cohorts, while multicenter, large cohorts have suggested little utility or no additional utility if routine UA/MCA/DV Doppler is performed, publication bias may have affected previous reports. It seems unlikely that MPI has clinical utility in assessment and management of SGA/FGR Fetuses. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd