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Marcelo Zugaib - One of the best experts on this subject based on the ideXlab platform.
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ductus venosus doppler and postnatal outcomes in fetuses with absent or reversed end diastolic flow in the Umbilical Arteries
European Journal of Obstetrics & Gynecology and Reproductive Biology, 2008Co-Authors: Sâmia K A Alves, Rossana Pulcineli Vieira Francisco, Seizo Miyadahira, Vera Lucia Jornada Krebs, Flavio Adolfo Costa Vaz, Marcelo ZugaibAbstract:Abstract Objective To evaluate the relationship between ductus venosus Doppler findings on the day of delivery and postnatal outcomes in pregnancies with absent or reversed end-diastolic (ARED) flow in the Umbilical Arteries. Study design Postnatal outcomes of 103 newborns of pregnancies with a diagnosis of ARED flow on Doppler velocimetry of the Umbilical Arteries were analyzed retrospectively between January 1997 and December 2004. Single pregnancies and fetuses without malformations were included. The cases were divided into two groups according to the flow during atrial contraction (a-wave) in the ductus venosus on the day of delivery: group A, 20 cases with absent or reversed flow in the ductus venosus and group B, 83 cases with positive flow. The results were analyzed statistically using the chi-square test, Fisher's exact test and the Mann-Whitney U test with the level of significance set at 5%. Results All newborns were delivered by cesarean section. Gestational age was similar in the two groups (group A: 30 weeks and group B: 30.9 weeks, P = 0.23). Absent or reversed ductus venosus flow was associated with the following adverse postnatal outcomes: lower birthweight ( P P = 0.001) and fifth minute ( P = 0.001), a higher frequency of orotracheal intubation ( P = 0.001) and pH at birth less than 7.20 ( P P = 0.03), thrombocytopenia ( P = 0.02), hypoglycemia ( P = 0.01), intracranial hemorrhage ( P = 0.02), and postnatal death ( P = 0.007). Conclusion The study of ductus venosus flow may provide additional information regarding the best time for interruption of pregnancies with ARED flow in the Umbilical Arteries characterized by extreme prematurity.
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predicting ph at birth in absent or reversed end diastolic velocity in the Umbilical Arteries
Obstetrics & Gynecology, 2006Co-Authors: Rossana Pulcineli Vieira Francisco, Seizo Miyadahira, Marcelo ZugaibAbstract:OBJECTIVE To investigate arterial and venous blood flow in fetuses with absent or reversed end-diastolic flow in the Umbilical Arteries and to correlate the Doppler results with Umbilical artery blood pH at birth to predict the probability of acidosis at birth. METHODS Ninety-one fetuses from singleton pregnancies without fetal malformations with a diagnosis of absent or reversed end-diastolic flow in the Umbilical Arteries were prospectively studied. On the day of delivery, Doppler velocimetry of the Umbilical Arteries, middle cerebral artery, and ductus venosus was performed and the results were correlated with Umbilical artery pH at birth at the following cutoff levels: pH < 7.20, < 7.15, < 7.10, and < 7.05. The association between fetal arterial and venous Doppler velocimetry and acidosis was then individually analyzed by the chi(2) and Fisher exact tests. The ability of these tests to predict the probability of acidosis at birth was estimated using a logistic regression model. RESULTS There was a negative correlation between pH at birth and Umbilical artery pulsatility index (r = -0.39; P < .001) and pulsatility index for veins in the ductus venosus (r = -0.63; P < .001). Assessment of the fetal arterial circulation (middle cerebral artery) showed no statistical correlation with pH at birth. Using logistic regression analysis, probability curves were constructed for pH values less than 7.20 (odds ratio [OR] 8.03), less than 7.15 (OR 11.92), less than 7.10 (OR 12.16), and less than 7.05 (OR 8.20). CONCLUSION The pulsatility index for veins of the ductus venosus was related to pH at birth, demonstrating that the higher the ductus venosus pulsatility index for veins, the lower the pH at birth. Once the pulsatility index for veins in the ductus venosus is known, the probability of acidosis at birth can be estimated.
Elisa Cairrão - One of the best experts on this subject based on the ideXlab platform.
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uv b filter octylmethoxycinnamate induces vasorelaxation by ca2 channel inhibition and guanylyl cyclase activation in human Umbilical Arteries
International Journal of Molecular Sciences, 2019Co-Authors: Margarida Lorigo, Carla Quintaneiro, Manuel C Lemos, Jose Martinezdeoliveira, Luiza Breitenfeld, Elisa CairrãoAbstract:Ultraviolet (UV) filters are chemicals widely used in personal care products (PCPs). Due to their effect as endocrine disruptor compounds (EDCs), the toxicity of UV filters is a current concern for human health. EDC exposure may be correlated to cardiovascular diseases (CVD), but to our knowledge, no studies assessed the UV filters effects as human EDCs at the vascular level. Octylmethoxycinnamate (OMC) is the world's most widely used UV-B filter, present in more than 90% of PCPs. Due to its demonstrated multiple hormonal activities in animal models, this substance is also suspected to be a human EDC. The purpose of this study was to assess the rapid/short-term effects of OMC on arterial tonus and analyse its mode of action (MOA). Using human Umbilical Arteries, the endocrine effects of OMC were evaluated in in vitro (cellular and organ) experiments by planar cell surface area (PCSA) and organ bath, respectively. Our data show that OMC induces a rapid/short-term smooth muscle relaxation acting through an endothelium-independent MOA, which seems to be shared with oestrogens, involving an activation of soluble guanylyl cyclase (sGC) that increases the cyclic guanosine monophosphate (cGMP) intracellular levels and an inhibition of L-type voltage-operated Ca2+ channels (L-Type VOCC).
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PDE4 and PDE5 regulate cyclic nucleotides relaxing effects in human Umbilical Arteries
European Journal of Pharmacology, 2007Co-Authors: António José Santos-silva, Elisa Cairrão, Manuel Morgado, Ezequiel Álvarez, Ignacio VerdeAbstract:Cyclic nucleotides (cAMP and cGMP) are the main second messengers linked to vasodilatation. They are synthesized by cyclases and degraded by different types of phosphodiesterases (PDE). The effect of PDE inhibition and cyclases stimulation on 5-hydroxytryptamine (5-HT; 1 microM) and histamine (10 microM) contracted Arteries was analysed. Stimulation of guanylate cyclase or adenylate cyclase relaxed the histamine- and 5-HT-induced contractions indicating that intracellular increase of cyclic nucleotides leads to vasodilatation of the human Umbilical artery. We investigated the role of different PDE families in the regulation of this effect. The presence of the different PDE types in human Umbilical artery smooth muscle was analysed by RT-PCR and the expression of PDE1B, PDE3A, PDE3B, PDE4C, PDE4D and PDE5A was detected. The unspecific PDE inhibitor 3-isobutyl-1-methylxanthine (IBMX; 50 microM) relaxed histamine-contracted human Umbilical artery on 47.4+/-7.2%. This effect seems to be due to PDE4 and PDE5 inhibition because among the selective PDE inhibitors used only the PDE4 inhibitor (rolipram; 1 microM) and the PDE5 inhibitors (dipyridamole and T0156; 3 microM and 1 microM respectively) induced significant relaxation (39.0+/-8.7, 30.4+/-6.0 and 36.3+/-2.8 respectively). IBMX, dipyridamole and T0156 produced similar relaxation on 5-HT-induced contraction. After forskolin, the addition of IBMX or rolipram increased the effect of the adenylate cyclase stimulator and almost completely relaxed the human Umbilical artery contracted by histamine (92.5+/-4.9 and 90.9+/-4.7 respectively), suggesting a main role of PDE4. The data obtained with 5-HT contracted Arteries confirmed this, because only rolipram and IBMX significantly increased the forskolin vasodilator effect. The administration of dipyridamole and T0156 after sodium nitroprusside (SNP) induced a significant increase of the SNP relaxant effect on histamine-contracted Arteries, but PDE1 and PDE3 inhibition did not increase the effect of the guanylate cyclase stimulator. Similar effects were obtained in 5-HT contracted Arteries, the SNP induced relaxation was increased by the PDE5 inhibition, but not by PDE1 or PDE3 inhibition. In summary, our results demonstrate that: 1) the increase of cAMP and/or cGMP levels induces relaxation of the human Umbilical vascular smooth muscle; 2) four families of PDE are expressed in this smooth muscle: PDE1, PDE3, PDE4 and PDE5; 3) between these families, PDE4 and PDE5 are the key enzymes involved in the regulation of the relaxation associated to cAMP and cGMP, respectively.
John Kingdom - One of the best experts on this subject based on the ideXlab platform.
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a puzzling intrauterine death non compaction of the fetal ventricular myocardium presenting with reversed end diastolic flow velocity in the Umbilical Arteries
Journal of obstetrics and gynaecology Canada, 2005Co-Authors: Cameron Ellis, Helen Pymar, Rory Windrim, Sarah Keating, John KingdomAbstract:Abstract Background: Absent or reversed end-diastolic flow velocity (ARED) in the Umbilical Arteries is typically associated with severe intrauterine growth restriction (IUGR), although there may be other causes, such as aneuploidy. Case: A healthy 30-year-old gravida 2, para 0 woman with an uneventful pregnancy and normal prenatal screening test results presented with sudden cessation of fetal movement at 26 weeks' gestation. Ultrasound demonstrated unexplained AIRED with normal fetal growth and normal amniotic fluid volume. The fetus died during transfer to the labour and delivery unit. The cause of fetal demise was initially assumed to be feto-maternal hemorrhage, but postmortem examination revealed non-compaction of the ventricular myocardium. Conclusion: Intrinsic myocardial disease should be considered in the differential diagnosis when AIRED is discovered in the Umbilical Arteries, especially when fetal growth is normal. Postmortem examination should be performed even if a prior 18- to 20-week anatomical ultrasound has been reported as normal.
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prognostic value of placental ultrasound in pregnancies complicated by absent end diastolic flow velocity in the Umbilical Arteries
Placenta, 2004Co-Authors: Sandra Viero, Rory Windrim, Vandana Chaddha, Fawaz Alkazaleh, M J Simchen, A Malik, Edmond Kelly, John KingdomAbstract:Our objective was to evaluate the utility of gray-scale placental ultrasound for the detection of pathological lesions in the placentas of preterm pregnancies with abnormal fetoplacental blood flow (defined by absent or reversed end-diastolic flow velocities [ARED] in the Umbilical Arteries) before 32 weeks of gestation. Sixty consecutive structurally and chromosomally normal singleton pregnancies were evaluated. Pre-defined criteria were used to describe placental appearances using gray-scale real-time ultrasound. Proximal uterine artery Doppler waveforms were recorded using pulsed and color Doppler ultrasound. Each patient had a thrombophilia profile. Following delivery, a single perinatal pathologist reviewed each placenta at a gross and microscopic level blinded to the placental ultrasound findings. Placental shape or texture was abnormal on gray-scale ultrasound in 43/59 (73%) and echogenic cystic lesions (ECL) were found in 16 (27%). Uterine artery Doppler was abnormal in 47/60 (78%) cases. Thirty-eight pregnancies were subsequently delivered by planned Caesarean section in the fetal and/or maternal interest (birthweights 540-2300 g, mean gestational age 30.6 weeks) and 21 pregnancies resulted in the vaginal delivery of a stillborn fetus where fetal weight and/or gestational age did not justify Caesarean section (birthweights 85-600 g, mean gestational age 24.9 weeks). ECL had a low positive predictive value for both villous infarcts (63%) and for focal/massive perivillous fibrin deposition (40%). Nevertheless, the combination of abnormal uterine artery Doppler and abnormal gray-scale findings (abnormal placental morphology or ECL) was strongly predictive of stillbirth (17/21; sensitivity 81%, PPV 52%, p = 0.006 Fisher's exact test). Pregnancies with ARED in the Umbilical Arteries have a high perinatal mortality associated with pathology of the placental villi. Ultrasound examination of the placenta and its maternal blood supply may contribute to the perinatal management of these pregnancies.
Patrick Menu - One of the best experts on this subject based on the ideXlab platform.
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Endothelialized and preconditioned natural Umbilical Arteries with long term patency open the route for future human uses
Clinical Hemorheology and Microcirculation, 2013Co-Authors: Estelle Paternotte, Halima Kerdjoudj, J F Stoltz, J C Voegel, Tunay Kökten, Anna Kearney-schwartz, Patrick MenuAbstract:The major challenge of vascular tissue engineering is to develop a small calibre vascular graft with a high patency rate. In native vessels, the thrombosis is prevented by the endothelium located at the luminal site of the vessel. The aim of this study was to develop a resistant endothelial lining on the inner surface of vascular graft using a polyelectrolyte multilayers (PEM) film. Umbilical Arteries were de-endothelialized, coated with 3.5 bilayers of poly(styrene sulfonate) (PSS)/poly(allylamine hydrochloride) (PAH) and then cellularized with endothelial cells. The grafts were cultured for a week in static condition and preconditioned by exposure to a shear stress of at 1 Pa for three hours before implantation on the rabbit carotid site. Histological and confocal microscopy in vitro investigations showed that PEMs films improve cell adhesion and retention on the luminal surface after shear stress preconditioning. In vivo Doppler data showed that graft preconditioning is a crucial factor for graft patency. Indeed, preconditioned grafts remained over the whole experimental period, whereas unpreconditioned grafts were obstructed after only one week of implantation. These results open the route toward the development of a new generation of vascular substitutes having a long term patency.
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small vessel replacement by human Umbilical Arteries with polyelectrolyte film treated Arteries in vivo behavior
Journal of the American College of Cardiology, 2008Co-Authors: Halima Kerdjoudj, Nicolas Berthelemy, Simon Rinckenbach, Anna Kearneyschwartz, Karine Montagne, Pierre Schaaf, Patrick Lacolley, J F Stoltz, J C Voegel, Patrick MenuAbstract:Objective The aim of this study was to evaluate the patency of human Umbilical Arteries treated with polyelectrolyte multilayers (PEMs) after rabbit implantation. Background The development of small-caliber vascular substitutes with high patency after implantation remains a real challenge for vascular tissue engineering. Methods Cryopreserved human Umbilical Arteries were enzymatically de-endothelialized and the luminal surfaces were coated with poly(styrene sulfonate)/poly(allylamine hydrochloride) (PSS/PAH) multilayers. The PEM-untreated Arteries and PEM-treated rabbit carotids were used as graft control. The native rabbit carotids were bypassed by grafts. Results The Doppler ultrasound evaluation, performed in vivo, showed that all PEM-treated grafts remained patent during the full experimental period, whereas after only 1 week, no blood circulation was detected in untreated Arteries. Scanning electron microscopy and histological graft examination showed pervasive thrombus formation on the luminal surface of untreated Arteries after 1 week and clean luminal surface for treated Arteries for at least up to 12 weeks. The arterial wall cells were identified through alpha-smooth muscle actin αυδ platelet endothelial cell adhesion molecule-1 expression. The smooth muscle cells positive to alpha-smooth muscle actin were identified in adventitia and media and the endothelial cells positive to platelet endothelial cell adhesion molecule in intima. Von Kossa reaction didn't reveal any calcium salt deposits on the wall Arteries, suggesting a good wall remodelling with no sign of graft rejection. Conclusions The in vivo evaluation of human Umbilical Arteries treated with PSS/PAH multilayers demonstrated a high graft patency after 3 months of implantation. Such modified Arteries could constitute a useful option for small vascular replacement.
Rossana Pulcineli Vieira Francisco - One of the best experts on this subject based on the ideXlab platform.
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ductus venosus doppler and postnatal outcomes in fetuses with absent or reversed end diastolic flow in the Umbilical Arteries
European Journal of Obstetrics & Gynecology and Reproductive Biology, 2008Co-Authors: Sâmia K A Alves, Rossana Pulcineli Vieira Francisco, Seizo Miyadahira, Vera Lucia Jornada Krebs, Flavio Adolfo Costa Vaz, Marcelo ZugaibAbstract:Abstract Objective To evaluate the relationship between ductus venosus Doppler findings on the day of delivery and postnatal outcomes in pregnancies with absent or reversed end-diastolic (ARED) flow in the Umbilical Arteries. Study design Postnatal outcomes of 103 newborns of pregnancies with a diagnosis of ARED flow on Doppler velocimetry of the Umbilical Arteries were analyzed retrospectively between January 1997 and December 2004. Single pregnancies and fetuses without malformations were included. The cases were divided into two groups according to the flow during atrial contraction (a-wave) in the ductus venosus on the day of delivery: group A, 20 cases with absent or reversed flow in the ductus venosus and group B, 83 cases with positive flow. The results were analyzed statistically using the chi-square test, Fisher's exact test and the Mann-Whitney U test with the level of significance set at 5%. Results All newborns were delivered by cesarean section. Gestational age was similar in the two groups (group A: 30 weeks and group B: 30.9 weeks, P = 0.23). Absent or reversed ductus venosus flow was associated with the following adverse postnatal outcomes: lower birthweight ( P P = 0.001) and fifth minute ( P = 0.001), a higher frequency of orotracheal intubation ( P = 0.001) and pH at birth less than 7.20 ( P P = 0.03), thrombocytopenia ( P = 0.02), hypoglycemia ( P = 0.01), intracranial hemorrhage ( P = 0.02), and postnatal death ( P = 0.007). Conclusion The study of ductus venosus flow may provide additional information regarding the best time for interruption of pregnancies with ARED flow in the Umbilical Arteries characterized by extreme prematurity.
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predicting ph at birth in absent or reversed end diastolic velocity in the Umbilical Arteries
Obstetrics & Gynecology, 2006Co-Authors: Rossana Pulcineli Vieira Francisco, Seizo Miyadahira, Marcelo ZugaibAbstract:OBJECTIVE To investigate arterial and venous blood flow in fetuses with absent or reversed end-diastolic flow in the Umbilical Arteries and to correlate the Doppler results with Umbilical artery blood pH at birth to predict the probability of acidosis at birth. METHODS Ninety-one fetuses from singleton pregnancies without fetal malformations with a diagnosis of absent or reversed end-diastolic flow in the Umbilical Arteries were prospectively studied. On the day of delivery, Doppler velocimetry of the Umbilical Arteries, middle cerebral artery, and ductus venosus was performed and the results were correlated with Umbilical artery pH at birth at the following cutoff levels: pH < 7.20, < 7.15, < 7.10, and < 7.05. The association between fetal arterial and venous Doppler velocimetry and acidosis was then individually analyzed by the chi(2) and Fisher exact tests. The ability of these tests to predict the probability of acidosis at birth was estimated using a logistic regression model. RESULTS There was a negative correlation between pH at birth and Umbilical artery pulsatility index (r = -0.39; P < .001) and pulsatility index for veins in the ductus venosus (r = -0.63; P < .001). Assessment of the fetal arterial circulation (middle cerebral artery) showed no statistical correlation with pH at birth. Using logistic regression analysis, probability curves were constructed for pH values less than 7.20 (odds ratio [OR] 8.03), less than 7.15 (OR 11.92), less than 7.10 (OR 12.16), and less than 7.05 (OR 8.20). CONCLUSION The pulsatility index for veins of the ductus venosus was related to pH at birth, demonstrating that the higher the ductus venosus pulsatility index for veins, the lower the pH at birth. Once the pulsatility index for veins in the ductus venosus is known, the probability of acidosis at birth can be estimated.
