References of "Lorquet, Sophie"
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See detailDifferential expression of Vegfr-2 and its soluble form in preeclampsia.
Munaut, Carine ULg; LORQUET, Sophie ULg; Pequeux, Christel ULg et al

in PLoS ONE (2012), 7(3), 33475

Background: Several studies have suggested that the main features of preeclampsia (PE) are consequences of endothelial dysfunction related to excess circulating anti-angiogenic factors, most notably ... [more ▼]

Background: Several studies have suggested that the main features of preeclampsia (PE) are consequences of endothelial dysfunction related to excess circulating anti-angiogenic factors, most notably, soluble sVEGFR-1 (also known as sFlt-1) and soluble endoglin (sEng), as well as to decreased PlGF. Recently, soluble VEGF type 2 receptor (sVEGFR-2) has emerged as a crucial regulator of lymphangiogenesis. To date, however, there is a paucity of information on the changes of VEGFR-2 that occur during the clinical onset of PE. Therefore, the aim of our study was to characterize the plasma levels of VEGFR-2 in PE patients and to perform VEGFR-2 immunolocalization in placenta. METHODOLOGY/PRINCIPAL FINDINGS: By ELISA, we observed that the VEGFR-2 plasma levels were reduced during PE compared with normal gestational age matched pregnancies, whereas the VEGFR-1 and Eng plasma levels were increased. The dramatic drop in the VEGFR-1 levels shortly after delivery confirmed its placental origin. In contrast, the plasma levels of Eng and VEGFR-2 decreased only moderately during the early postpartum period. An RT-PCR analysis showed that the relative levels of VEGFR-1, sVEGFR-1 and Eng mRNA were increased in the placentas of women with severe PE. The relative levels of VEGFR-2 mRNA as well as expressing cells, were similar in both groups. We also made the novel finding that a recently described alternatively spliced VEGFR-2 mRNA variant was present at lower relative levels in the preeclamptic placentas. CONCLUSIONS/SIGNIFICANCE: Our results indicate that the plasma levels of anti-angiogenic factors, particularly VEGFR-1 and VEGFR-2, behave in different ways after delivery. The rapid decrease in plasma VEGFR-1 levels appears to be a consequence of the delivery of the placenta. The persistent circulating levels of VEGFR-2 suggest a maternal endothelial origin of this peptide. The decreased VEGFR-2 plasma levels in preeclamptic women may serve as a marker of endothelial dysfunction. [less ▲]

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See detailAetiology and physiopathology of preeclampsia and related forms.
Lorquet, Sophie ULg; Pequeux, Christel ULg; Munaut, Carine ULg et al

in Acta Clinica Belgica (2010), 65(4), 237-41

Preeclampsia, a pregnancy-specific syndrome characterized by hypertension, proteinuria and oedema, resolves on placental delivery. Its pathogenesis is thought to be associated to a hypoxic placenta ... [more ▼]

Preeclampsia, a pregnancy-specific syndrome characterized by hypertension, proteinuria and oedema, resolves on placental delivery. Its pathogenesis is thought to be associated to a hypoxic placenta. Placental hypoxia is responsible for the maternal vascular dysfunction via the increased placental release of anti-angiogenic factors such as soluble flt1 and endoglin. These soluble receptors bind VEGF, PLGF and TGFbeta1 and 3 in the maternal circulation, causing endothelial dysfunction in many maternal tissues. Despite these recent and important new molecular findings, it is important to consider that normal pregnancy is also characterized by systemic inflammation, oxidative stress and alterations in levels of angiogenic factors and vascular reactivity. Both the placenta and maternal vasculatures are major sources of reactive oxygen and nitrogen species which can produce powerful pro-oxidants that covalently modify proteins and alter vascular function in preeclampsia. Finally, the recent demonstration of activating auto-antibodies to the Angiotensin 1 receptor that experimentally play a major pathogenic role in preeclampsia further indicates the pleiotropism of aetiologies of this condition. [less ▲]

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See detailSoluble forms of VEGF receptor-1 and -2 promote vascular maturation via mural cell recruitment.
LORQUET, Sophie ULg; Berndt, Sarah; Blacher, Silvia ULg et al

in FASEB Journal (2010), 24(10), 3782-95

Two soluble forms of vascular endothelial growth factor (VEGF) receptors, sVEGFR-1 and sVEGFR-2, are physiologically released and overproduced in some pathologies. They are known to act as anti-VEGF ... [more ▼]

Two soluble forms of vascular endothelial growth factor (VEGF) receptors, sVEGFR-1 and sVEGFR-2, are physiologically released and overproduced in some pathologies. They are known to act as anti-VEGF agents. Here, we report that these soluble receptors contribute to vessel maturation by mediating a dialogue between endothelial cells (EC) and mural cells that leads to blood vessel stabilization. Through a multidisciplinary approach, we provide evidences that these soluble VEGF receptors promote mural cell migration through a paracrine mechanism involving interplay in EC between VEGF/VEGFR-2 and sphingosine-1- phosphate type-1 (S1P)/S1P1 pathways that leads to endothelial nitric oxyde synthase (eNOS) activation. This new paradigm is supported by the finding that sVEGFR-1 and -2: 1) induce an eNOS-dependent outgrowth of a mural cell network in an ex vivo model of angiogenesis, 2) increase the mural cell coverage of neovessels in vitro and in vivo, 3) promote mural cell migration towards EC, 4) stimulate endothelial S1P1 overproduction and eNOS activation that promote the migration and the recruitment of neighboring mural cells. These findings provide new insights into mechanisms regulating physiological and pathological angiogenesis and vessel stabilization. [less ▲]

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See detailChorionic Gonadotropin Stimulation of Angiogenesis and Pericyte Recruitment
Berndt, Sarah; Blacher, Silvia ULg; PERRIER d'HAUTERIVE, Sophie ULg et al

in Journal of Clinical Endocrinology and Metabolism (2009), 94(11), 4567-74

During the periimplantation period, human chorionic gonadotropin (hCG) plays a key role by increasing the uterine blood flow through uterine vessel vasodilatation but also through angiogenesis. Indeed, we ... [more ▼]

During the periimplantation period, human chorionic gonadotropin (hCG) plays a key role by increasing the uterine blood flow through uterine vessel vasodilatation but also through angiogenesis. Indeed, we previously demonstrated that hCG contributes to endothelial cell recruitment and vessel formation. OBJECTIVE: In this study, hCG was proposed as an arteriogenic factor that could promote perivascular cell recruitment and vessel stabilization. DESIGN: The aortic ring assay, a three-dimensional ex vivo angiogenesis system mimicking all the steps of the angiogenesis process was used to study the impact of hCG on pericyte recruitment and vessel maturation. SETTING: The study was conducted at a university hospital laboratory. MAIN OUTCOME MEASURES: Perivascular cell proliferation, migration, and apposition were quantified by computerized image analysis. RESULTS: Physiological concentrations of hCG (10-400 IU/ml) significantly enhanced pericyte sprouting and migration and gave rise to the maturation and coverage of endothelial capillaries. In a three-dimensional coculture model of endothelial and perivascular cells, hCG enhanced vessel tube formation and endothelial/mural cell adhesion. In addition, hCG stimulated the proliferation of human umbilical vein endothelial cells and smooth muscle cells. The specificity of these effects was determined by using an anti-hCG blocking antibody. Signaling pathways implicated on this hCG effect is protein kinase A and phospholipase C/protein kinase C dependent for the proliferative effect but only phospholipase C/protein kinase C for the migrative process. CONCLUSIONS: Our findings highlight a novel paracrine role of this early embryonic signal in vessel maturation by stimulating perivascular cell recruitment, migration, and proliferation. [less ▲]

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See detailLes défauts d'implantation placentaire et leurs conséquences sur la fonction endothéliale maternelle
Foidart, Jean-Michel ULg; Noël, Agnès ULg; Chantraine, Frédéric ULg et al

in Bulletin Académique National de Médecine (2009), 193(5), 1059-66

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See detailDysregulation of anti-angiogenic agents (sFlt-1, PLGF, and sEndoglin) in preeclampsia--a step forward but not the definitive answer
Foidart, Jean-Michel ULg; Schaaps, Jean-Pierre ULg; Chantraine, Frédéric ULg et al

in Journal of Reproductive Immunology (2009), 82(2), 106-11

Preeclampsia (PE) is a pregnancy-specific syndrome characterized by hypertension, proteinuria and edema, which resolves on placental delivery. It is thought to be the consequence of impaired placentation ... [more ▼]

Preeclampsia (PE) is a pregnancy-specific syndrome characterized by hypertension, proteinuria and edema, which resolves on placental delivery. It is thought to be the consequence of impaired placentation due to inadequate trophoblastic invasion of the maternal spiral arteries. In PE the maternal plasma concentration of free vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) is decreased whereas the concentration of soluble fms-like tyrosine kinase-1 (sFlt-1) and of soluble endoglin (sEng) is increased. These soluble receptors may bind VEGF, PLGF and TGFβ1 and TGFβ3 in the maternal circulation, causing endothelial dysfunction in many maternal tissues. Hence there is a view that the pathogenesis is more or less clarified. According to the vascular theory, poor placentation leads to poor uteroplacental perfusion and hypoxia, which stimulates sFlt-1 and sEng production causing the maternal syndrome. This assumption has been recently challenged. The role of hypoxia as the main stimulus for release of sFlt-1 has been questioned and the role of inflammatory mechanisms has been emphasized. According to this inflammatory theory, poor placentation may predispose more to placental oxidative stress than hypoxia and endothelial dysfunction may be part of a broader disorder of systemic inflammation. Finally, the recent demonstration of activating auto-antibodies to the angiotensin 1 receptor that experimentally play a major pathogenic role in PE further suggests a pleiotropism of aetiologies for this condition. The purpose of this review is to critically evaluate the recent hypotheses and their possible insights on early diagnosis, prevention and treatment. [less ▲]

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See detailHypoxia is responsible for soluble vascular endothelial growth factor receptor-1 (VEGFR-1) but not for soluble endoglin induction in villous trophoblast
Munaut, Carine ULg; Lorquet, Sophie ULg; Pequeux, Christel ULg et al

in Human Reproduction (2008), 23(6), 1407-15

BACKGROUND: Pre-eclampsia is a pregnancy disorder characterized by a maternal endothelial cell dysfunction associated with low levels of circulating placental growth factor (PlGF) and increased levels of ... [more ▼]

BACKGROUND: Pre-eclampsia is a pregnancy disorder characterized by a maternal endothelial cell dysfunction associated with low levels of circulating placental growth factor (PlGF) and increased levels of total vascular endothelial growth factor (VEGF), soluble VEGF receptor-1 (sVEGFR-1), and soluble endoglin, a transforming growth factor b1 and 3 coreceptor. Here, we tested the hypothesis that these altered levels of angiogenic cytokines and of the anti-angiogenic soluble forms of cytokine receptors could be the consequence of hypoxia. METHODS: Normal human umbilical vein endothelial cells, immortalized first trimester extravillous trophoblast cells (HTR8/SVneo) and first trimester placental villi explants (8–14 weeks) were used for culture under normoxia (20% O2) or hypoxia (1% O2). Culture media were collected for the measurement of cytokines by enzyme-linked immunosorbent assay. Total RNA was extracted for RT-PCR analysis. RESULTS: Under hypoxia, villous trophoblast expressed higher levels of VEGF, VEGFR-1, sVEGFR-1 and VEGFR-2 mRNAs (P < 0.001), and secreted more VEGF and sVEGFR-1 proteins (P < 0.05). In contrast, PlGF mRNA and protein were decreased in 1% O2 (P < 0.001), whereas endoglin (Eng) was not modulated. Additionally, sVEGFR-1 directly abolished VEGF/PlGF-induced angiogenesis in the rat aortic ring assay. CONCLUSIONS: Our results support the hypotheses that, in pre-eclampsia, (i) overproduction of VEGF family factors by pre-eclamptic placenta is a consequence of induced hypoxia; (ii) overproduction of sVEGFR-1 by hypoxic villous trophoblast accounts for maternal free VEGF depletion; (iii) low circulating level of free PlGF is not only related to sVEGFR-1 overproduction, but also to hypoxia induced mRNA down-regulation; (iv) Eng is not modulated by hypoxia.. [less ▲]

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See detailImplication of soluble receptors of VEGF, sVEGFR-1 and sVEGFR-2, in angiogenesis
Lorquet, Sophie ULg; Berndt, Sarah ULg; Blacher, Silvia ULg et al

in American Journal of Reproductive Immunology (2008), 60/1

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See detailImplication of VEGF receptor soluble forms, sVEGFR-1 and sVEGFR-2, in angiogenesis
Lorquet, Sophie ULg; Berndt, Sarah ULg; Blacher, Silvia ULg et al

in Acta Clinica Belgica (2008), 63/1

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See detailAngiogenic activity of human chorionic gonadotropin through LH receptor activation on endothelial and epithelial cells of the endometrium
Berndt, Sarah ULg; PERRIER d'HAUTERIVE, Sophie ULg; Blacher, Silvia ULg et al

in FASEB Journal (2006), 20(14), 2630-2632

Successful embryo development requires an extensive endometrial angiogenesis in proximity of implantation site. The glycoprotein hCG is produced even before implantation by trophoblast in normal pregnancy ... [more ▼]

Successful embryo development requires an extensive endometrial angiogenesis in proximity of implantation site. The glycoprotein hCG is produced even before implantation by trophoblast in normal pregnancy. In this manuscript, we demonstrate an angiogenic effect of hCG in several in vivo (chick chorioallantoic membrane, matrigel plug assay, aortic ring assay) and in vitro experimental models. In contrast, human placental lactogen (hPL) did not display angiogenic properties. LH/hCG receptor was detected in endothelial cells by reverse-transcriptase polymerase chain reaction (RT-PCR) and by Western blotting. In mice aortic ring assay, angiostimulation by hCG was abrogated by deletion of LH/hCG receptor (LuRKO mice). Use of recombinant hCG and anti-hCG antibody (Ab) further confirmed the specificity of this angiogenic activity. By using dibutyryl cAMP, adenylate cyclase, or protein kinase A inhibitors, we demonstrate that hCG-mediated angiogenesis involves adenylyl-cyclase-protein kinase A activation. Addition of hCG to endometrial epithelial epithelial cells, but not to cultured endothelial cells, stimulated vascular endothelial growth factor (VEGF). VEGF and hCG also displayed additive activities. Altogether, these data demonstrate that peritrophoblastic angiostimulation may result from a paracrine dialogue between trophoblast, epithelial, and endothelial cells through hCG and VEGF. [less ▲]

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See detailKilling Kinetics of Group B Streptococci for Penicillin in Combination with Gentamicin
Melin, Pierrette ULg; Lorquet, Sophie ULg; Hayette, Marie-Pierre ULg et al

in Sriprakash, Kabada S (Ed.) "Streptococci: New Insights into an Old Enemy", Proceedings of the XVI Lancefield International Symposium on Streptococci and Streptococcal Diseases (2006)

In vitro synergism and killing kinetics studies of penicillin in combination with gentamicin were performed with group B streptococci recently isolated in Belgium. The expected accelerated killing was not ... [more ▼]

In vitro synergism and killing kinetics studies of penicillin in combination with gentamicin were performed with group B streptococci recently isolated in Belgium. The expected accelerated killing was not observed when compared with penicillin alone. D 2005 Elsevier B.V. All rights reserved. [less ▲]

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See detailLe cas clinique du mois: un dysgerminome bilateral: une presentation rare du syndrome de Swyer
Nisolle, Michelle ULg; Kridelka, Frédéric ULg; Fridman, Viviana ULg et al

in Revue Médicale de Liège (2005), 60(9), 703-6

Swyer syndrome is a pure gonad dysgenesis associating 46 XY karyotype, primary amenorrhea, presence of female internal genital tract and bilateral streak gonads in a phenotypic female. The diagnosis is ... [more ▼]

Swyer syndrome is a pure gonad dysgenesis associating 46 XY karyotype, primary amenorrhea, presence of female internal genital tract and bilateral streak gonads in a phenotypic female. The diagnosis is usually made at adolescence when the primary amenorrhea is investigated. We report the case of a 25-year-old XY woman who developed a bilateral dysgerminoma from undifferentiated gonads. [less ▲]

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See detailLe streptocoque du groupe B en clinique antenatale et en salle de travail: un probleme d'attitude systematique
Lorquet, Sophie ULg; Melin, Pierrette ULg; Minon, Jean-Marc et al

in Journal de Gynécologie, Obstétrique et Biologie de la Reproduction (2005), 34(2), 115-27

OBJECTIVES: We wanted to evaluate the compliance to the local recommendations, similar to the CDC (Centers for Disease Control and prevention) recommendations launched in 1996, for the prevention of ... [more ▼]

OBJECTIVES: We wanted to evaluate the compliance to the local recommendations, similar to the CDC (Centers for Disease Control and prevention) recommendations launched in 1996, for the prevention of perinatal group B streptococcal (GBS) disease in the clinical practice of a academic maternity and to identify the causes of missed screening and antibiotic prophylaxis. MATERIALS AND METHODS: Retrospective study of 1249 consecutive pregnancies between 1st January and 31th August 2002. The screening methods for GBS colonisation were the culture of rectovaginal swabs collected between 35 and 37 weeks and/or a rapid antigenic screening performed on a vaginal swab collected at the patient's admission for labor. RESULTS: Rate of global screening was very high (97.8%): 28.8% of antenatal screening versus 90.3% during labor. An appropriate antibiotic prophylaxis was administered to only one-third of positive women when the screening was performed at admission to the labor room, whereas two-thirds of GBS-positive women screened between 35 and 37 weeks received their antibiotic prophylaxis. 2.4%o of the newborns were infected and 2.9% were colonized. Among the different risk factors, intrapartum fever was more often associated with maternal GBS colonisation. The observed sensitivity of the rapide antigenic test was 20.4%. CONCLUSION: Compliance to guidelines is sometimes difficult in the clinical practice of an academic maternity. In our hands the rapid test for GBS screening had low sensitivity. The analysis of these data led to introducing a computerized algorithm in our maternity to improve the prevention of perinatal group B streptococcal disease. [less ▲]

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See detailL'image du mois. Ulcere perineal chez une patiente atteinte de spina bifida
Lorquet, Sophie ULg; Conti, V.; Nervo, Patricia ULg et al

in Revue Médicale de Liège (2004), 59(12), 688-90

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