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1.
Microsc Microanal ; 29(4): 1523-1530, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37488818

RESUMO

Culture of shell-free and windowed eggs for drug testing and other experiments has been perfected for smaller eggs such as those of chickens, where the developing blood vessels of the chorioallantoic membrane (CAM) become accessible for manipulative studies. However, due to the thickness and hardness of the ostrich egg shell, such techniques are not applicable. Using a tork craft mini rotary and a drill bit, we established windowed egg, in-shell-membrane windowed egg, and in-shell-membrane shell-free methods in the ostrich egg, depending on whether the shell membranes were retained or not. Concomitant study of the developing CAM revealed that at embryonic day 16 (E16), the three layers of the CAM were clearly delineated and at E25, the chorionic capillaries had fused with the epithelium while the CAM at E37 had reached maturity and the chorion and the allantois were both 3-4 times thicker and villous cavity (VC) and capillary-covering cells were well delineated. Both intussusceptive and sprouting angiogenesis were found to be the predominant modes of vascular growth in the ostrich CAM. Development and maturation of the ostrich CAM are similar to those of the well-studied chicken egg, albeit its incubation time being twice in duration.


Assuntos
Membrana Corioalantoide , Struthioniformes , Animais , Membrana Corioalantoide/irrigação sanguínea , Galinhas , Alantoide/irrigação sanguínea , Córion/irrigação sanguínea
2.
ACS Appl Mater Interfaces ; 13(28): 32662-32672, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34240610

RESUMO

The lack of small-diameter vascular grafts (inner diameter <5 mm) to substitute autologous grafts in arterial bypass surgeries has a massive impact on the prognosis and progression of cardiovascular diseases, the leading cause of death globally. Decellularized arteries from different sources have been proposed as an alternative, but their poor mechanical performance and high collagen exposure, which promotes platelet and bacteria adhesion, limit their successful application. In this study, these limitations were surpassed for decellularized umbilical cord arteries through the coating of their lumen with graphene oxide (GO). Placental and umbilical cord arteries were decellularized and perfused with a suspension of GO (C/O ratio 2:1) with ∼1.5 µm lateral size. A homogeneous GO coating that completely covered the collagen fibers was obtained for both arteries, with improvement of mechanical properties being achieved for umbilical cord decellularized arteries. GO coating increased the maximum force in 27%, the burst pressure in 29%, the strain in 25%, and the compliance in 10%, compared to umbilical cord decellularized arteries. The achieved theoretical burst pressure (1960 mmHg) and compliance (13.9%/100 mmHg) are similar to the human saphenous vein and mammary artery, respectively, which are used nowadays as the gold standard in coronary and peripheral artery bypass surgeries. Furthermore, and very importantly, coatings with GO did not compromise the endothelial cell adhesion but decreased platelet and bacteria adhesion to decellularized arteries, which will impact on the prevention of thrombosis and infection, until full re-endothetialization is achieved. Overall, our results reveal that GO coating has an effective role in the improvement of decellularized umbilical cord artery performance, which is a huge step toward their application as a small-diameter vascular graft.


Assuntos
Prótese Vascular , Materiais Revestidos Biocompatíveis/química , Grafite/química , Artérias Umbilicais/química , Aderência Bacteriana/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Córion/irrigação sanguínea , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Placenta/irrigação sanguínea , Gravidez
3.
Twin Res Hum Genet ; 23(3): 178-183, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32248867

RESUMO

Our objective was to determine whether chorionicity affects umbilical cord blood acid-base parameters of the second twin. This was a retrospective cohort of twin pregnancies delivered at ≥23 weeks of gestation at a tertiary hospital from 2010 to 2016. Patients were included if arterial and venous umbilical cord gas results were available for both newborns and chorionicity was confirmed histologically. Exclusion criteria included intrauterine fetal demise of either twin prior to labor, major fetal anomalies, monoamnionicity, uncertain chronicity and twin-to-twin transfusion syndrome. The primary outcome evaluated was the umbilical artery (UA) pH of the second twin. A total of 593 dichorionic (DC) and 86 monochorionic (MC) twin pregnancies were included. No difference in UA pH was observed between MC and DC twins. Among vaginal deliveries (n = 97), the UA pH of the first twin was higher than the second twin (7.26 vs. 7.24; p = .01). Twin-to-twin delivery interval (TTDI) ≥20 min was associated with a higher UA pH in the first twin compared to the second twin (7.25 vs. 7.16, respectively; p = .006). Multivariable logistic regression was used to predict arterial pH < 7.20 for the second twin; the most predictive factors were arterial pH < 7.20 for the first twin, chronic hypertension and prolonged TTDI. Chorionicity was not associated with any acid-base parameter of umbilical cord blood in either the first or second twin. No differences in neonatal outcomes were observed based on chorionicity or birth order. Populations with a lower cesarean delivery rate may yield different findings.


Assuntos
Córion/irrigação sanguínea , Sangue Fetal/metabolismo , Transfusão Feto-Fetal/sangue , Adulto , Cesárea , Córion/metabolismo , Estudos de Coortes , Parto Obstétrico , Feminino , Transfusão Feto-Fetal/genética , Transfusão Feto-Fetal/patologia , Idade Gestacional , Humanos , Hipertensão/sangue , Hipertensão/patologia , Recém-Nascido , Gravidez , Gravidez de Gêmeos/genética , Gravidez de Gêmeos/metabolismo , Estudos Retrospectivos , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Artérias Umbilicais/metabolismo
4.
J Neonatal Perinatal Med ; 13(1): 97-104, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31796686

RESUMO

INTRODUCTION: Extremely preterm infants are a population of high risk for morbidity and mortality. NICU's staffing is often lower during nights, weekends and holidays than weekdays, and this fact may contribute to higher morbidities and mortality. Our aim was to analyze the neonatal morbidity and mortality of very preterm infants delivered at our center and admitted to the NICU during the night period, weekends and holidays compared to that registered on weekday admissions. METHODS: A retrospective study was conducted at our level III NICU, including data on mother, pregnancy, delivery, and neonatal outcomes of preterm infants with a gestational age below 30 weeks, admitted between January 1st 2005 and December 31st 2017. Statistical analysis was performed using IBM SPSS® Statistics 23. RESULTS: 220 infants were included in the study; median gestational age 27 weeks (min = 23; max = 29); median birth weight of 922 g (min = 360; max1555); 95 (43.2%) infants were delivered during weekdays and 125 (56.8%) were delivered during weeknights, weekends and holidays. There were no differences on mother's age, pregnancy complications, Apgar scores, birth weights, gestational ages and gender between the two groups. C-sections (p = 0.006), and small for gestational age infants (p = 0.010) were more prevalent in week day births. Chorioamnionitis with chorionic vasculitis (p = 0.028) and cystic periventricular leukomalacia (p = 0.032) were more prevalent in those delivered during the night period, weekends and holidays. In the multivariate analysis, cystic periventricular leukomalacia was not associated to a deliver during weeknights, weekends and holidays (OR = 0.580; 95% CI: 0.19-1.71, p = 0.324). CONCLUSION: We did not find any increased morbidity and mortality associated with a birth during nights, weekends and holidays compared to that registered on weekday admissions.


Assuntos
Plantão Médico/estatística & dados numéricos , Cesárea/estatística & dados numéricos , Corioamnionite/epidemiologia , Unidades de Terapia Intensiva Neonatal , Leucomalácia Periventricular/epidemiologia , Admissão e Escalonamento de Pessoal , Vasculite/epidemiologia , Córion/irrigação sanguínea , Enterocolite Necrosante/epidemiologia , Feminino , Idade Gestacional , Mortalidade Hospitalar , Humanos , Lactente Extremamente Prematuro , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Tempo de Internação/estatística & dados numéricos , Masculino , Análise Multivariada , Sepse Neonatal/epidemiologia , Gravidez , Prevalência , Respiração Artificial/estatística & dados numéricos , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Retinopatia da Prematuridade/epidemiologia , Estudos Retrospectivos
5.
Int J Pharm ; 561: 236-243, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30853484

RESUMO

While vascular endothelial growth factor (VEGF) is an acknowledged potent pro-angiogenic agent there is a need to deliver it at an appropriate concentration for several days to achieve angiogenesis. The aim of this study was to produce microspheres of biodegradable polylactic-co-glycolic acid (PLGA) tailored to achieve sustained release of VEGF at an appropriate concentration over seven days, avoiding excessive unregulated release of VEGF that has been associated with the formation of leaky blood vessels. Several formulations were examined to produce microspheres loaded with both human serum albumin (HSA) and VEGF to achieve release of VEGF between 3 and 10 ng per ml for seven days to match the therapeutic window desired for angiogenesis. In vitro experiments showed an increase in endothelial cell proliferation in response to microspheres bearing VEGF. Similarly, when microspheres containing VEGF were added to the chorionic membrane of fertilised chicken eggs, there was an increase in the development of blood vessels over seven days in response, which was significant for microspheres bearing VEGF and HSA, but not VEGF alone. There was an increase in both blood vessel density and branching - both signs of proangiogenic activity. Further, there was clearly migration of cells to the VEGF loaded microspheres. In summary, we describe the development of an injectable delivery vehicle to achieve spatiotemporal release of physiologically relevant levels of VEGF for several days and demonstrate the angiogenic response to this. We propose that such a treatment vehicle would be suitable for the treatment of ischemic tissue or wounds.


Assuntos
Liberação Controlada de Fármacos , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Albumina Sérica/química , Fator A de Crescimento do Endotélio Vascular/química , Animais , Plásticos Biodegradáveis/química , Proliferação de Células/fisiologia , Galinhas , Córion/irrigação sanguínea , Preparações de Ação Retardada/química , Composição de Medicamentos/métodos , Células Endoteliais/fisiologia , Humanos , Neovascularização Fisiológica/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/farmacologia
6.
Nitric Oxide ; 80: 82-88, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30179715

RESUMO

Adequate perfusion of the placental vasculature is essential to meet the metabolic demands of fetal growth and development. Lacking neural control, local tissue metabolites, circulating and physical factors contribute significantly to blood flow regulation. Nitric oxide (NO) is a key regulator of fetoplacental vascular tone. Nitrite, previously considered an inert end-product of NO oxidation, has been shown to provide an important source of NO. Reduction of nitrite to NO may be particularly relevant in tissue when the oxygen-dependent NO synthase (NOS) activity is compromised, e.g. in hypoxia. The contribution of this pathway in the placenta is currently unknown. We hypothesised that nitrite vasodilates human placental blood vessels, with enhanced efficacy under hypoxia. Placentas were collected from uncomplicated pregnancies and the vasorelaxant effect of nitrite (10-6-5x10-3 M) was assessed using wire myography on isolated pre-constricted chorionic plate arteries (CPAs) and veins (CPVs) under normoxic (pO2 ∼5%) and hypoxic (pO2 ∼1%) conditions. The dependency on the NO-sGC-cGMP pathway and known nitrite reductase (NiR) activities was also investigated. Nitrite caused concentration-dependent vasorelaxation in both arteries and veins, and this effect was enhanced by hypoxia, significantly in CPVs (P < 0.01) and with a trend in CPAs (P = 0.054). Pre-incubation with NO scavengers (cPTIO and oxyhemoglobin) attenuated (P < 0.01 and P < 0.0001, respectively), and the sGC inhibitor ODQ completely abolished nitrite-mediated vasorelaxation, confirming the involvement of NO and sGC. Inhibition of potential NiR enzymes xanthine oxidoreductase, mitochondrial aldehyde dehydrogenase and mitochondrial bc1 complex did not attenuate vasorelaxation. This data suggests that nitrite may provide an important reservoir of NO bioactivity within the placenta to enhance blood flow when fetoplacental oxygenation is impaired, as occurring in pregnancy diseases such as pre-eclampsia and fetal growth restriction.


Assuntos
Artérias/fisiologia , Córion/irrigação sanguínea , Hipóxia/metabolismo , Nitritos/metabolismo , Veias/fisiologia , Adulto , Artérias/efeitos dos fármacos , Benzoatos/farmacologia , GMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Imidazóis/farmacologia , Nitritos/farmacologia , Placenta/irrigação sanguínea , Gravidez , Nitrito de Sódio/administração & dosagem , Nitrito de Sódio/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia , Veias/efeitos dos fármacos
7.
PLoS One ; 13(8): e0202648, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30142162

RESUMO

INTRODUCTION: Preeclampsia is a major health problem in human pregnancy, severely complicating 5-8% of all pregnancies. The emerging molecular mechanism is that conditions like hypoxic stress trigger the release of placental messengers into the maternal circulation, which causes preeclampsia. Our objective was to develop an in vitro model, which can be used to further elucidate the molecular mechanisms of preeclampsia and which might be used to find a remedy. METHODS: Human non-complicated term placentas were collected. Placental explants were subjected to severe hypoxia and the conditioned media were added to chorionic arteries that were mounted into a myograph. Contractile responses of the conditioned media were determined, as well as effects on thromboxane-A2 (U46619) induced contractility. To identify the vasoactive compounds present in the conditioned media, specific receptor antagonists were evaluated. RESULTS: Factors released by placental explants generated under severe hypoxia induced an increased vasoconstriction and vascular contractility to thromboxane-A2. It was found that agonists for the angiotensin-I and endothelin-1 receptor released by placental tissue under severe hypoxia provoke vasoconstriction. The dietary antioxidant quercetin could partially prevent the acute and sustained vascular effects in a concentration-dependent manner. DISCUSSION: Both the acute vasoconstriction, as well as the increased contractility to U46619 are in line with the clinical vascular complications observed in preeclampsia. Data obtained with quercetin supports that our model opens avenues for e.g. nutritional interventions aimed at treating or preventing preeclampsia.


Assuntos
Constrição Patológica/genética , Placenta/metabolismo , Pré-Eclâmpsia/genética , Vasoconstrição/genética , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Córion/irrigação sanguínea , Córion/metabolismo , Córion/patologia , Constrição Patológica/fisiopatologia , Meios de Cultivo Condicionados/farmacologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Feminino , Humanos , Hipóxia/genética , Hipóxia/patologia , Contração Muscular/efeitos dos fármacos , Miografia , Placenta/patologia , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/fisiopatologia , Gravidez , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia
8.
Diab Vasc Dis Res ; 15(6): 528-540, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30130976

RESUMO

BACKGROUND: There is clinical and experimental evidence for altered adenosine signalling in the fetoplacental circulation in pregnancies complicated by diabetes, leading to adenosine accumulation in the placenta. However, the consequence for fetoplacental vasocontractility is unclear. This study examined contractility to adenosine of chorionic vessels from type 1 diabetes mellitus, gestational diabetes mellitus and normal pregnancies. METHODS: Chorionic arteries and veins were isolated from human placenta from normal, gestational diabetes mellitus and type 1 diabetes mellitus pregnancies. Isometric tension recording measured responses to adenosine and the thromboxane A2 analogue U46619 (thromboxane A2 mediates fetoplacental vasoconstriction to adenosine). Adenosine and thromboxane prostanoid receptor protein expression was determined by immunoblotting. RESULTS: Adenosine elicited contractions in chorionic arteries and veins which were impaired in both gestational diabetes mellitus and type 1 diabetes mellitus. Contractions to potassium chloride were unchanged. Adenosine A2A and A2B receptor protein levels were not different in gestational diabetes mellitus and normal pregnancies. Contractions to U46619 were unaltered in gestational diabetes mellitus arteries and increased in type 1 diabetes mellitus arteries. Overnight storage of vessels restored contractility to adenosine in gestational diabetes mellitus arteries and normalized contraction to U46619 in type 1 diabetes mellitus arteries. CONCLUSION: These data are consistent with the concept of aberrant adenosine signalling in diabetes; they show for the first time that this involves impaired adenosine contractility of the fetoplacental vasculature.


Assuntos
Adenosina/farmacologia , Artérias/efeitos dos fármacos , Córion/irrigação sanguínea , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Gestacional/fisiopatologia , Gravidez em Diabéticas/fisiopatologia , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , Veias/efeitos dos fármacos , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Artérias/metabolismo , Artérias/fisiopatologia , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/metabolismo , Feminino , Humanos , Gravidez , Gravidez em Diabéticas/diagnóstico , Gravidez em Diabéticas/metabolismo , Receptor A2A de Adenosina/metabolismo , Receptor A2B de Adenosina/metabolismo , Receptor A3 de Adenosina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Nascimento a Termo , Veias/metabolismo , Veias/fisiopatologia
9.
Biomaterials ; 177: 14-26, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29885585

RESUMO

Small diameter vascular grafts from human placenta, decellularized with either Triton X-100 (Triton) or SDS and crosslinked with heparin were constructed and characterized. Graft biochemical properties, residual DNA, and protein composition were evaluated to compare the effect of the two detergents on graft matrix composition and structural alterations. Biocompatibility was tested in vitro by culturing the grafts with primary human macrophages and in vivo by subcutaneous implantation of graft conduits (n = 7 per group) into the flanks of nude rats. Subsequently, graft performance was evaluated using an aortic implantation model in Sprague Dawley rats (one month, n = 14). In situ graft imaging was performed using MRI angiography. Retrieved specimens were analyzed by electromyography, scanning electron microscopy, histology and immunohistochemistry to evaluate cell migration and the degree of functional tissue remodeling. Both decellularization methods resulted in grafts of excellent biocompatibility in vitro and in vivo, with low immunogenic potential. Proteomic data revealed removal of cytoplasmic proteins with relative enrichment of ECM proteins in decelluarized specimens of both groups. Noteworthy, LC-Mass Spectrometry analysis revealed that 16 proteins were exclusively preserved in Triton decellularized specimens in comparison to SDS-treated specimens. Aortic grafts showed high patency rates, no signs of thrombus formation, aneurysms or rupture. Conduits of both groups revealed tissue-specific cell migration indicative of functional remodeling. This study strongly suggests that decellularized allogenic grafts from the human placenta have the potential to be used as vascular replacement materials. Both detergents produced grafts with low residual immunogenicity and appropriate mechanical properties. Observed differences in graft characteristics due to preservation method had no impact on successful in vivo performance in the rodent model.


Assuntos
Artérias/química , Prótese Vascular , Matriz Extracelular/química , Placenta/irrigação sanguínea , Proteínas/análise , Alicerces Teciduais/química , Animais , Aorta/cirurgia , Fenômenos Biomecânicos , Implante de Prótese Vascular , Córion/irrigação sanguínea , Matriz Extracelular/ultraestrutura , Proteínas da Matriz Extracelular/análise , Feminino , Humanos , Masculino , Gravidez , Ratos Nus , Ratos Sprague-Dawley
10.
Front Med ; 12(5): 542-549, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29520693

RESUMO

Preeclampsia (PE) is a pregnancy-specific, multi-system disorder and the leading cause of maternal and perinatal morbidity and mortality in obstetrics worldwide. Excessive vasoconstriction and dysregulated coagulation function are closely associated with PE. Heat shock protein 20 (HSP20) is ubiquitously expressed under normal physiological conditions and has important roles in vascular dilatation and suppression of platelet aggregation. However, the role of HSP20 in the pathogenesis of PE remains unclear. In this study, we collected chorionic plate resistance arteries (CPAs) and serum from 118 healthy pregnant women and 80 women with PE and detected the levels of HSP20 and its phosphorylated form. Both HSP20 and phosphorylated HSP20 were downregulated in CPAs from women with PE. Comparison of the vasodilative ability of CPAs from the two groups showed impaired relaxation responses to acetyl choline in preeclamptic vessels. In addition to the reduced HSP20 in serum from women with PE, the platelet distribution width and mean platelet volume were also decreased, and the activated partial thromboplastin time and thromboplastin time were elevated.With regard to the vital roles of HSP20 in mediating vasorelaxation and coagulation function, the decreased HSP20 might contribute to the pathogenesis of PE.


Assuntos
Córion/irrigação sanguínea , Proteínas de Choque Térmico HSP20/metabolismo , Placenta/irrigação sanguínea , Pré-Eclâmpsia/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Fosforilação , Testes de Função Plaquetária , Gravidez , Vasoconstrição , Vasodilatação
11.
PLoS One ; 13(3): e0192122, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29579054

RESUMO

Pre-eclampsia is associated with altered maternal and placental vascular reactivity. Kv7 channels (encoded by KCNQ 1-5 genes) are a potential contributor to the regulation of vascular tone in CPAs (chorionic plate arteries) during normal pregnancy. The aim of this study is to establish the expression profile of KCNQ subunits in CPAs taken from women with preeclampsia or normotensive women and to examine the functional relevance of the Kv7 channels on an altered expression profile of KCNQ subunits. The effects of Kv7 channel modulators on CPAs were investigated by tension measurement. Quantitative PCR experiments were used to analyze the expression of KCNQ genes. Western blotting and immunofluorescence were both used to analyze the protein expression of Kv7 channels. Finally, in CPAs from normotensive women, the Kv7 channel blocker XE991 increased arterial basal tone and U46619-induced contraction, and pre-contracted CPAs (10-7 M U46619) exhibited significant relaxation following treatment with Retigabine(Kv7.2-7.5 activator) and BMS-204352(Kv7.2-7.5 activator). However, ICA-27243(selective KCNQ2 and KCNQ3 activator) and ML277(selective KV7.1 activator) had no significant effect on tension in the pre-contracted CPAs. Conversely, compared with CPAs from normotensive women, the effects of XE991 on basal tone and agonist (U46619)-induced contractions in CPAs from women with preeclampsia were markedly attenuated. Moreover, the relaxation effects of Retigabine and BMS-204352 on pre-contracted CPA vessels from women with pre-eclampsia were also markedly down-regulated. Interestingly, the relaxation ability of ICA-27243 in pre-contracted CPA vessels in women with pre-eclampsia was enhanced. The mRNA of KCNQ3 was specifically up-regulated, whereas those for KCNQ4 and KCNQ5 were down-regulated in CPAs from women with pre-eclampsia compared with those in normotensive women. Similar observations were found in a subsequent analysis of protein expression of KCNQ genes 3-5. Thus, down-regulated Kv7 channel function in tension regulation of CPAs in women with pre-eclampsia could be associated with considerably altered expression profiles of Kv7 subunits.


Assuntos
Artérias/metabolismo , Córion/irrigação sanguínea , Perfilação da Expressão Gênica , Canais de Potássio KCNQ/genética , Pré-Eclâmpsia/genética , Artérias/fisiopatologia , Feminino , Humanos , Canais de Potássio KCNQ/metabolismo , Moduladores de Transporte de Membrana/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Pré-Eclâmpsia/metabolismo , Gravidez , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
12.
BJOG ; 125(9): 1154-1162, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29380497

RESUMO

OBJECTIVES: Preterm premature rupture of membranes (PPROM) is a leading complication following fetoscopic laser coagulation (FLC) for twin-twin transfusion syndrome (TTTS). Our primary objective was to describe the impact of improvements in surgical technique on survival and rate of PPROM over time. The secondary objective was to assess potential risk factors for PPROM. DESIGN AND SETTING: Single-centre retrospective observational study. POPULATION: 1092 consecutive cases of TTTS operated by FLC between 2000 and 2016, with a 6.8% rate of loss to follow up. METHODS: The incidence of PPROM and potential risk factors were analysed using competing risks models. MAIN OUTCOME MEASURES: PPROM, neonatal survival and neurological damage at 28 days. RESULTS: PPROM <32 weeks increased from 15 to 40% between 2000 and 2016 along with an overall improvement of perinatal outcomes: dual survival rose from 42 to 66% whereas dual losses dropped two-fold, from 19 to 9%. Gestational age at surgery at <17 weeks was a significant risk-factor for PPROM, with an additional risk of 10% within the first week of surgery. Although early PPROM at <20 weeks carried a 56% risk of miscarriage, the occurrence of PPROM at >20 weeks did not affect survival, despite an increase in preterm birth at <32 weeks. CONCLUSIONS: With significant improvement in perinatal outcomes, possibly related to improvements in surgical technique, postoperative complications have shifted to non-lethal obstetric complications such as PPROM, with rather reassuring postnatal outcomes, despite an increase in preterm birth and, potentially, morbidity. Early surgeries (<17 weeks) are at higher risk of postoperative PPROM. TWEETABLE ABSTRACT: Following laser/TTTS, rates of PPROM increased with perinatal survival; surgeries at <17 weeks are at highest risk.


Assuntos
Ruptura Prematura de Membranas Fetais/etiologia , Transfusão Feto-Fetal/cirurgia , Fetoscopia/efeitos adversos , Fotocoagulação a Laser/efeitos adversos , Córion/irrigação sanguínea , Córion/cirurgia , Feminino , Fetoscopia/métodos , Humanos , Fotocoagulação a Laser/métodos , Gravidez , Resultado da Gravidez , Gravidez de Gêmeos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Gêmeos Monozigóticos
13.
Hypertens Res ; 41(2): 126-134, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29142264

RESUMO

Preeclampsia has known associations with insufficient placental perfusion. The large-conductance Ca2+-activated K+ (BKca) channels that have recently been found to play important roles in cellular growth and vasodilatation could potentially participate in the development of preeclampsia. However, the mechanisms by which downregulated BKca channels are involved in the development of preeclampsia remain unknown. In this study, we investigated the mechanism(s) underlying the impairment of vascular tone regulation by BKca channels in human placental chorionic plate arteries (CPAs) in preeclampsia. The levels of BKca channel α and ß1 subunits were compared using immunohistochemistry, western blotting, and RT-PCR in CPAs of normal and preeclamptic pregnant women. To explore the role of BKca channels in the regulation of proliferation and apoptosis in human placental CPA smooth muscle cells (SMCs), a specific BKca opener, NS1619, was used to investigate proliferative reduction and apoptotic induction in human placental chorionic plate arterie smooth muscle cells (CPASMCs) collected from normal pregnancies. The vasodilator effects of BKca channels and their response to SNP (an NO donor) in both groups were also evaluated by wire myography. We found that BKca channel ß1 subunits were less expressed in preeclamptic CPAs. After pretreatment with NS1619, cellular proliferation was significantly suppressed, and cellular apoptosis was dramatically promoted in cultured CPASMCs, demonstrating a relationship between increased Bax expression and decreased Bcl-2 expression in CPASMCs. Downregulated BKca is also associated with decreased vasodilatation and reduced susceptibility to NO donors. In conclusion, the decreased expression or activation of BKca channels may induce pathologic remodeling of human CPAs, weaken the vasodilation response, and decrease vascular sensitivity to vasoactive substances, thereby reducing fetal-placental blood flow and leading to the future development of preeclampsia.


Assuntos
Artérias/fisiopatologia , Córion/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/fisiopatologia , Adulto , Apoptose , Proliferação de Células , Córion/irrigação sanguínea , Córion/fisiopatologia , Feminino , Humanos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Doadores de Óxido Nítrico/farmacologia , Nitroprussiato/farmacologia , Placenta/irrigação sanguínea , Placenta/fisiopatologia , Gravidez , Proteína X Associada a bcl-2/biossíntese , Proteína X Associada a bcl-2/genética
14.
Gynecol Obstet Fertil Senol ; 45(5): 269-275, 2017 May.
Artigo em Francês | MEDLINE | ID: mdl-28479073

RESUMO

OBJECTIVES: The aim of the study is to compare placental monochorionic angioarchitecture complicated with twin-oligohydramnios-polyhydramnios sequence (TOPS), twin anemia polycythemia sequence (TAPS), twin reversed arterial perfusion (TRAP) and selective intra uterine growth restriction (sIUGR) to normal uneventful monochorionic placenta. METHODS: Between December 2012 and December 2015, monochorionic placenta has been studied at the multiple pregnancy care center of the Femme-Mère-Enfant Hospital in Lyon. Umbilical chords were catheterized and dye injected for macroscopic analysis of angioarchitecture at the anatomopathology department. Placentas treated with laser foetoscopic surgery were excluded. RESULTS: A total of 126 placentas were injected in the post-partum period. In total, 95% (119/126) of the placentas presented arteriovenous anastomoses (AVA). Median number of AVA was 7. The prevalence of at least one velamentous cord insertion was higher in TOPS and selective intrauterine growth restrictions P<0.01 and P<0.01 respectively, compared to uneventful pregnancies. Arterio-arterial anastomoses (AAA) were present in 82.7% (77/93) of uneventful placentas versus 33.3% of TOPS (P<0.01) and 28.5% of TAPS (P<0.01). The prevalence of veno-venous anastomoses was significantly higher in TOPS (P<0.01). All TAPS placentas showed marginal arteriovenous anastomoses. In TRAP placenta, the acardiac twin had no specific vascular territory. CONCLUSION: The study confirms literature findings on prevalence of vascular anastomoses in monochorial placentas, suggesting the protective role of AAA in TOPS and TAPS. The role of VVA is yet hard to determinate. Macroscopic observations of monochorionic placentas are valuable and essential keys for understanding, managing and treating anastomotic syndromes.


Assuntos
Córion/irrigação sanguínea , Placenta/irrigação sanguínea , Complicações na Gravidez/patologia , Gravidez de Gêmeos , Anastomose Arteriovenosa/patologia , Doenças em Gêmeos/patologia , Feminino , Retardo do Crescimento Fetal/patologia , Transfusão Feto-Fetal/patologia , Humanos , Poli-Hidrâmnios , Gravidez , Gêmeos Monozigóticos , Cordão Umbilical/patologia
15.
Bull Exp Biol Med ; 162(4): 507-509, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28243905

RESUMO

Smooth muscle cells from the arterial wall of placental chorion were studied at 39-40-week gestation. The content of mono- and binuclear tetraploid myocytes was higher in sites of arterial branching and turns (27.3% vs. 4.4% straight parts of the arteries; DNA cytophotometry data). Mitoses were found only in these arterial regions (0.18%). Regional changes in the sizes of diploid and polyploid myocytes were detected, associated with the blood flow pattern in the chorion; myocyte hypertrophy was 17-fold more incident in sites of arterial turns and branching than in straight arteries. Possible causes of changes in the proliferative characteristics and subsequent growth of the chorionic arterial wall myocytes are discussed.


Assuntos
Artérias/citologia , Núcleo Celular/ultraestrutura , Córion/irrigação sanguínea , Miócitos de Músculo Liso/citologia , Placenta/irrigação sanguínea , Ploidias , Velocidade do Fluxo Sanguíneo , Separação Celular/métodos , Forma Celular , Córion/citologia , DNA/química , Feminino , Humanos , Índice Mitótico , Fenótipo , Placenta/citologia , Gravidez , Cultura Primária de Células
16.
Ultrasound Obstet Gynecol ; 50(6): 723-727, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28150444

RESUMO

OBJECTIVE: Single intrauterine death (sIUD) in twin pregnancy is associated with a significant risk of cotwin demise and preterm birth (PTB), especially in monochorionic (MC) twins. However, it is yet to be established whether the gestational age at loss may influence the pregnancy outcome. The aim of this study was to explore the risk of PTB according to the gestational age at diagnosis of sIUD. METHODS: This was a cohort study of all twin pregnancies booked for antenatal care in a large regional network of nine hospitals over a 10-year period. Ultrasound data were matched to hospital delivery records and to a mandatory national register for stillbirth and neonatal loss provided by the Centre for Maternal and Child Enquires. Cases with double fetal loss at the time of the scan and cases of sIUD occurring at or after 34 weeks of gestation were not included in the analysis. The relative risk (RR) of PTB at < 34, < 32 and < 28 weeks of gestation in twin pregnancies complicated by sIUD was assessed and compared with that in twin pregnancies without fetal loss. The risk of PTB at < 34 weeks was stratified according to the gestational age at diagnosis of sIUD. The risk of PTB in twin pregnancy after sIUD according to the gestational age at death was also explored. RESULTS: The analysis included 3013 twin gestations (2469 dichorionic (DC) and 544 MC). Median gestational age at birth was lower in the pregnancies complicated by sIUD compared with those that were not (32.0 weeks: interquartile range (IQR), 29.0-34.3 weeks vs 36.7 weeks: IQR, 35.0-37.6; P < 0.001) and this difference persisted when stratifying the data according to chorionicity (P < 0.0001 for both MC and DC pregnancies). The risk of PTB at < 34 weeks (RR, 4.3 (95% CI, 3.5-5.2)), < 32 weeks (RR, 6.1 (95% CI, 4.6-8.1)) and < 28 weeks (RR, 12.4 (95% CI, 6.9-22.2)) of gestation was higher in pregnancies complicated by sIUD compared with those which did not experience fetal loss. This association was observed both in MC and DC twin gestations. When compared with DC pregnancies, MC twins affected by sIUD were not at significantly increased risk of PTB before either 34, 32 or 28 weeks of gestation. The risk of PTB at < 34 weeks of gestation was higher when the sIUD occurred at a later gestational age (chi-square test for trend, P < 0.001). CONCLUSIONS: Twin pregnancies complicated by sIUD, regardless of the chorionicity, have a significantly higher risk of PTB at < 34, < 32 and < 28 weeks of gestation. The risk of PTB at < 34 weeks of gestation was higher when the sIUD occurred in the second half of the pregnancy. Large prospective multicenter studies with shared protocols for prenatal management are needed to ascertain the actual risk of spontaneous PTB in twin pregnancies affected by sIUD. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Aborto Espontâneo , Córion/diagnóstico por imagem , Morte Fetal , Gravidez de Gêmeos , Nascimento Prematuro/etiologia , Ultrassonografia Pré-Natal , Aborto Espontâneo/etiologia , Adulto , Córion/irrigação sanguínea , Feminino , Morte Fetal/etiologia , Idade Gestacional , Humanos , Incidência , Gravidez , Valores de Referência , Estudos Retrospectivos , Fatores de Risco , Gêmeos Monozigóticos , Reino Unido
17.
J Ultrasound Med ; 35(3): 553-60, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26892818

RESUMO

OBJECTIVES: The purpose of this study was to develop an ex vivo placental perfusion model to assess changes in the umbilical artery systolic-to-diastolic (S/D) ratio due to progressive occlusion of the placental arterial system. METHODS: Ex vivo human placentas were connected to a computerized pulse duplicator mimicking pulsatile flow from the fetal heart. Doppler sonographic measurements were conducted on the umbilical and chorionic arteries of 25 mature placentas. Simulation of placental occlusion was performed by progressive ligature of the chorionic arteries, including one umbilical artery. The correlation between the umbilical artery S/D ratio and the severity of simulated placental occlusion was analyzed. RESULTS: The normal mean S/D ratio ± SD decreased gradually along the chorionic plate from 2.66 ± 0.47 at the cord insertion to 1.90 ± 0.59 in generation IV of the chorionic vessels. The Doppler index initially increased slowly with simulated placental occlusion. Only when all 4 generations were occluded was the umbilical artery S/D ratio elevated. Complete occlusion of one umbilical artery resulted in a 39% increase in the umbilical artery S/D ratio. CONCLUSIONS: This unique model combining Doppler sonography with perfusion of an ex vivo placenta can be used for a better understudying of pathologic placental blood flow circulation.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Córion/fisiopatologia , Técnicas de Cultura de Órgãos/instrumentação , Técnicas de Cultura de Órgãos/métodos , Placenta/fisiologia , Artérias Umbilicais/fisiologia , Córion/irrigação sanguínea , Córion/diagnóstico por imagem , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Técnicas In Vitro , Placenta/irrigação sanguínea , Placenta/diagnóstico por imagem , Gravidez , Ultrassonografia Doppler/métodos , Ultrassonografia Pré-Natal/métodos , Artérias Umbilicais/irrigação sanguínea , Artérias Umbilicais/diagnóstico por imagem
18.
PLoS One ; 11(1): e0145649, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26751570

RESUMO

Monochronioric (MC) twin pregnancies are considered as high-risk pregnancies with potential complications requiring in-utero interventions. We aimed to assess prenatal attachment, anxiety, post-traumatic stress disorder (PTSD) and depressive symptoms in MC pregnancies complicated with Twin-To-Twin-transfusion syndrome (TTTS) in comparison to uncomplicated monochorionic (UMC) and dichorionic pregnancies (DC). Auto-questionnaires were filled out at diagnosis of TTTS and at successive milestones. Prenatal attachment, PTSD, anxiety and perinatal depression were evaluated respectively by the Prenatal Attachment Inventory (PAI) completed for each twin, the Post-traumatic Checklist Scale (PCLS), the State-Trait Anxiety Inventory (STAI) and the Edinburgh Perinatal Depression Scale (EPDS). There was no significant difference in the PAI scores between the two twins. In the DC and UMC groups, PAI scores increased throughout pregnancy, whilst it didn't for TTTS group. TTTS and DC had a similar prenatal attachment while MC mothers expressed a significantly higher attachment to their fetuses and expressed it earlier. At the announcement of TTTS, 72% of the patients present a score over the threshold at the EPDS Scale, with a higher score for TTTS than for DC (p = 0.005), and UMC (p = 0.007) at the same GA. 30% of mothers in TTTS group have PTSD during pregnancy. 50% of TTTS- patients present an anxiety score over the threshold (STAI-Scale), with a score significantly higher in TTTS than in UMC (p<0.001) or DC (p<0.001). The proportion of subject with a STAI-State over the threshold is also significantly higher in TTTS than in DC at 20 GW (p = 0.01) and at 26 GW (p<0.05). The STAI-state scores in UMC and DC increase progressively during pregnancy while they decrease significantly in TTTS. TTTS announcement constitutes a traumatic event during a pregnancy with an important risk of PTSD, high level of anxiety and an alteration of the prenatal attachment. These results should guide the psychological support provided to these patients.


Assuntos
Ansiedade/psicologia , Depressão/psicologia , Gravidez de Alto Risco/psicologia , Gravidez de Gêmeos/psicologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto , Ansiedade/fisiopatologia , Ansiedade/prevenção & controle , Córion/irrigação sanguínea , Córion/fisiopatologia , Depressão/fisiopatologia , Depressão/prevenção & controle , Aconselhamento Diretivo , Feminino , Transfusão Feto-Fetal/fisiopatologia , Humanos , Apego ao Objeto , Gravidez , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/prevenção & controle , Gêmeos Monozigóticos
19.
Fetal Diagn Ther ; 40(3): 181-186, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26760043

RESUMO

INTRODUCTION: This study aimed to determine the incidences of feto-fetal transfusion syndrome (FFTS) and perinatal outcomes in triplet gestations with monochorionic placentation. MATERIALS AND METHODS: In this retrospective cohort study, we evaluated the incidences of FFTS and perinatal outcomes at 28 days of age in cases of triplet gestations with monochorionic placentation who visited our centers before 16 weeks of gestation and delivered over a period of 11 years. RESULTS: In 41 triplet gestations (17 monochorionic triamniotic, 22 dichorionic triamniotic, 1 dichorionic diamniotic, and 1 monochorionic monoamniotic), the incidence of FFTS was 17.1%, and the median gestational age at FFTS diagnosis was 19 weeks. In 123 triplets, the incidences of fetal death and neonatal death at 28 days of age were 8.1 and 0.9%, respectively. None of the surviving infants had grade 3 or 4 intraventricular hemorrhage, while cystic periventricular leukomalacia occurred in 6 of 113 infants (5.3%). The incidence of poor outcomes (death or any major neurological complication at 28 days of age) was 13.8%. DISCUSSION: Seventeen percent of triplet pregnancies with monochorionic placentation developed FFTS, and 14% had a poor outcome. Therefore, triplet gestations with monochorionic placentation should be followed carefully.


Assuntos
Transfusão Feto-Fetal/epidemiologia , Gravidez de Trigêmeos , Adulto , Córion/irrigação sanguínea , Córion/patologia , Feminino , Transfusão Feto-Fetal/diagnóstico por imagem , Transfusão Feto-Fetal/cirurgia , Humanos , Placenta/irrigação sanguínea , Gravidez , Estudos Retrospectivos , Medição de Risco , Resultado do Tratamento
20.
Placenta ; 36(8): 944-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26100723

RESUMO

Variability in placental chorionic surface vessel networks (PCSVNs) may mark developmental and functional changes in fetal health. Here we report a protocol of manually tracing PCSVNs from digital 2D images of post-delivery placentas and its validation by a shape matching method to compare the similarity between paint-injected and unmanipulated (uninjected and deflated vessels) tracings of PCSVNs. We show that tracings of unmanipulated vessels produce networks that are very comparable to the networks obtained by tracing paint-injected PCSVNs. We suggest that manual tracings of unmanipulated PCSVNs can extract features of PCSVN growth and structure that may impact fetal wellbeing.


Assuntos
Algoritmos , Córion/irrigação sanguínea , Placenta/irrigação sanguínea , Feminino , Humanos , Gravidez , Cordão Umbilical/irrigação sanguínea
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