Expression et localisation spatio-temporelle de KISS1 et de son récepteur KISSR dans le placenta normal et pathologique.

Poster (2012, October)

Objectif : Etudier l’expression de KISS1 (métastatine) et de son récepteur KISS1R lors de la grossesse normale et pathologique. Matériels et méthodes : Nous avons étudié la localisation de KISS1 et KISS1R ... [more ▼]

Objectif : Etudier l’expression de KISS1 (métastatine) et de son récepteur KISS1R lors de la grossesse normale et pathologique. Matériels et méthodes : Nous avons étudié la localisation de KISS1 et KISS1R par immunohistochimie dans des placentas normaux (1 er et 3 ème trimestre). Par RT-PCR quantitative, nous avons évalué le niveau d’expression des ARNm dans les placentas et les lits placentaires correspondants. Les niveaux d’expression de ARNm ont été comparés entre les grossesses normales (GN, n=13) et les grossesses spathologiques Prééclampsiques -PE-, n=17 et retard de croissance intrautérine -RCIU-, n=9). Résultats : Au premier trimestre des GN, KISS1 est majoritairement localisé dans les syncitiotrophoblastes, alors que KISS1R est détecté dans le mesenchyme villositaire. Au cours du troisième trimestre, KISS1 est uniquement localisé dans le syncitiotrophoblaste au contact avec la décidue et dans le mésenchyme villositaire et KISS1R est détecté dans le trophoblaste extra-villeux ainsi que dans quelques cellules de la décidue. Les analyses par RT-PCR mettent en évidence une expression plus importante des ARNm de KISS1 (p<0,001) et de KISS1R (p=0.039) dans les placentas (GN,PE et RCIU) par rapport aux lits placentaires correspondants. Les niveaux d’expression de KISS1 et KISS1R ne sont pas, cependant, significativement modulés dans les grossesses pathologiques. Conclusions : Par immunohistochimie, nos résultats indiquent une expression spatiotemporelle différente pour KISS1 et KISS1R entre le 1 er et 3 ème trimestre des grossesses normales. Nous n’avons pas mis en évidence de modulation de l’expression des ARNm dans les grossesses pathologiques. [less ▲]

Differential expression of Vegfr-2 and its soluble form in preeclampsia.

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 ▲]

Abnormal vascular architecture at the placental-maternal interface in placenta increta

in American Journal of Obstetrics and Gynecology (2012), 207(3), 1881-9

Objective The objective of the study was to characterize the vascular architecture at the placental-maternal interface in pregnancies complicated by placenta increta and normal pregnancies. Study Design ... [more ▼]

Objective The objective of the study was to characterize the vascular architecture at the placental-maternal interface in pregnancies complicated by placenta increta and normal pregnancies. Study Design Vessel numbers and cross-section area density and spatial and area distributions in 13 placenta-increta placental beds were compared with 9 normal placental beds using computer-assisted image analysis of whole-slide CD31 immunolabeled sections. Results The total areas occupied by vessels in normal and placenta-increta placental beds were comparable, but vessels were significantly sparser and larger in the latter. Moreover, placenta-increta–vessel distributions (area and distance from the placental–myometrial junction) were more heterogeneous. Conclusion Size and spatial organization of the placenta-increta vascular architecture at the placental-maternal interface differed from normal and might partially explain the severe hemorrhage observed during placenta-increta deliveries. [less ▲]

Le cas clinique du mois. Hydrocephalie liee a i'X: a spropos d'un cas en medecine foetale.

in Revue Médicale de Liège (2011), 66(3), 126-9

X-linked hydrocephaly (Li Syndrome) is a rare cause of hydrocephaly. It is, however, the most common genetic form of congenital hydrocephaly and consists of the association of hydrocephaly, mental ... [more ▼]

X-linked hydrocephaly (Li Syndrome) is a rare cause of hydrocephaly. It is, however, the most common genetic form of congenital hydrocephaly and consists of the association of hydrocephaly, mental retardation, leg spasticity and adducted thumbs. The phenotype is variable. A mutation of the LICAM gene is known to be the aetiology of the syndrome. We present an antenatal case managed in our department. [less ▲]

Thiamine Status in Humans and Content of Phosphorylated Thiamine Derivatives in Biopsies and Cultured Cells

in PLoS ONE (2010), 5(10), 13616

Background Thiamine (vitamin B1) is an essential molecule for all life forms because thiamine diphosphate (ThDP) is an indispensable cofactor for oxidative energy metabolism. The less abundant thiamine ... [more ▼]

Background Thiamine (vitamin B1) is an essential molecule for all life forms because thiamine diphosphate (ThDP) is an indispensable cofactor for oxidative energy metabolism. The less abundant thiamine monophosphate (ThMP), thiamine triphosphate (ThTP) and adenosine thiamine triphosphate (AThTP), present in many organisms, may have still unidentified physiological functions. Diseases linked to thiamine deficiency (polyneuritis, Wernicke-Korsakoff syndrome) remain frequent among alcohol abusers and other risk populations. This is the first comprehensive study on the distribution of thiamine derivatives in human biopsies, body fluids and cell lines. Methodology and Principal Findings Thiamine derivatives were determined by HPLC. In human tissues, the total thiamine content is lower than in other animal species. ThDP is the major thiamine compound and tissue levels decrease at high age. In semen, ThDP content correlates with the concentration of spermatozoa but not with their motility. The proportion of ThTP is higher in humans than in rodents, probably because of a lower 25-kDa ThTPase activity. The expression and activity of this enzyme seems to correlate with the degree of cell differentiation. ThTP was present in nearly all brain and muscle samples and in ~60% of other tissue samples, in particular fetal tissue and cultured cells. A low ([ThTP]+[ThMP])/([Thiamine]+[ThMP]) ratio was found in cardiovascular tissues of patients with cardiac insufficiency. AThTP was detected only sporadically in adult tissues but was found more consistently in fetal tissues and cell lines. Conclusions and Significance The high sensitivity of humans to thiamine deficiency is probably linked to low circulating thiamine concentrations and low ThDP tissue contents. ThTP levels are relatively high in many human tissues, as a result of low expression of the 25-kDa ThTPase. Another novel finding is the presence of ThTP and AThTP in poorly differentiated fast-growing cells, suggesting a hitherto unsuspected link between these compounds and cell division or differentiation. [less ▲]

Ultrasound assessment of the intima and media layers on the carotid arteries in peri- and postmenopausal women

in European Journal of Ultrasound (2010), 31(S 01), 906

Prenatal diagnosis of benign extreme hyperlordosis.

in Journal of Ultrasound in Medicine : Official Journal of the American Institute of Ultrasound in Medicine (2009), 28(8), 1097

Les anomalies d'insertion placentaire

in Gunaïkeia (2009), 14(4), 121-123

A rare case of placental choriangioma associated with neonatal diffuse hemangomatosis.

in Journal de Gynécologie, Obstétrique et Biologie de la Reproduction (2009), 38(3), 246-249

Placental chorioangioma is a benign vascular tumor. Lesions larger than 4cm may cause fetal and maternal complications. Its association with disseminated neonatal hemangiomatosis is rarely described. We ... [more ▼]

Placental chorioangioma is a benign vascular tumor. Lesions larger than 4cm may cause fetal and maternal complications. Its association with disseminated neonatal hemangiomatosis is rarely described. We report a case of a large chorioangioma associated with an hydrops foetalis and disseminated neonatal hemangiomatosis. The relationship between placental chorioangioma and hemangioma is briefly discussed. [less ▲]

How I explore the benefit of 3D/4D ultrasound in obstetrics

in Revue Médicale de Liège (2008), 63(3), 153-7

During recent years, 3D has become an important tool in ultrasound. In obstetrics, the classic 2D examination with Doppler is now often completed by 3D. In this article the strengths and weaknesses of ... [more ▼]

During recent years, 3D has become an important tool in ultrasound. In obstetrics, the classic 2D examination with Doppler is now often completed by 3D. In this article the strengths and weaknesses of this technique are discussed. [less ▲]