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J P Schaaps

Publications and source records attributed to J P Schaaps.

At least 19 recordsLinked to original sources
PubMed2006

[New approaches to prenatal diagnosis of rhesus incompatibility].

Despite generalisation of anti-D immunoprophylaxis, RhD allo-immunisation still remains the major cause of severe haemolytic disease of the fetus and of the newborn (HDFN). The routine follow up of pregnant women comprises: the ABO/D, Rh/Kell red cells typing and the search for irregular antibodies. In case of anti-D immunisation, the paternal Rh phenotype, when known, provides useful information regarding the probability for the fetus to have inherited the D antigen and thereby to be exposed to the risk of HDFN. The antibody titre, which is predictive of possible in vivo haemolysis, must be interpreted in the light of the previous obstetric history, and can lead to the decision of invasive amniocentesis. Then the measurement of the optical density (deltaOD450 nm) and the fetal RhD typing can be realised on amniotic fluid. New molecular techniques make it possible now to demonstrate the presence of fetal DNA in maternal plasma. These methods lying on non invasive procedures could advantageously be applied to the genotyping of fetal RHD during pregnancy. The present paper aims to discuss the predictive values of RHD fetal genotype in maternal plasma of RhD negative mothers. The ante-partum management of immunised pregnant women is reviewed in the light of this new molecular approach combined to Doppler ultrasonography of the fetal middle cerebral artery. This non invasive method for determining fetal RHD genotype could be systematically proposed to all RhD negative pregnant women for a better targeted prenatal follow-up and an increased efficacy of RhD prophylaxis.

Algorithms↗
PubMed2003

Delayed delivery of second twin: a multicentre study of 35 cases.

OBJECTIVE: The aim of this study was to conduct a statistical analysis to determine the outcome of conservative treatment after delivery of a first fetus in multiple pregnancy and thus define new prognostic factors. STUDY DESIGN: Multicentre retrospective study involving 12 centers over a 10-year period. RESULTS: Twenty-eight twin pregnancies and seven triplet pregnancies which were managed conservatively. In twin pregnancies, 79% of the delayed-delivery fetuses survived; only 7% of the first delivered fetuses survived. The mean interval between deliveries was 47 days. No statistical difference was found concerning cerclage, antibiotic therapy, tocolysis and hospitalization. Earlier delivery of the first twin and premature rupture of membranes for the second twin were significantly related to a longer interval between deliveries. CONCLUSION: Delayed delivery in multifetal pregnancies can be successful if there are no contraindications and these pregnancies are managed in a tertiary perinatal center. Publications limited to successful cases have undoubtedly introduced some bias in assessment.

Anti-Bacterial Agents↗
PubMed2001

Fetal renal hyperechogenicity in intrauterine growth retardation: importance and outcome.

The object of the study was to investigate the outcome in growth-retarded newborns who were diagnosed with fetal renal hyperechogenicity without anatomical abnormality during any stage of pregnancy. Depending on the fetal renal ultrasonography result, the cases were divided into two study groups. There was an intrauterine growth-retarded group with fetal renal medullary hyperechogenicity and another group without fetal renal medullary hyperechogenicity. The renal parenchyma was observed after birth, within the first 5 days of life, and several times until the 14th postpartum day in positive cases. Hyperechogenic renal medullae were detected in 25 of 90 cases with intrauterine growth retardation during the 8-month study period. This may be an in utero cause of subsequent intrauterine and neonatal complications, such as cesarean section because of fetal distress (36%), perinatal infection (24%), treatment in a neonatal intensive care unit (52%), or increased perinatal mortality (8%). The results demonstrate that fetuses with hyperechoic medullae had 1.5 times the risk of an abnormal outcome compared with fetuses with normal echoic kidneys and intrauterine growth retardation. Detailed ultrasound examinations of renal parenchyma appear to be useful for the prenatal diagnosis of intrauterine hypoxia, allowing the detection of possible pathological fetal conditions in utero.

Adult↗
PubMed2000

Embryonic and early fetal development of the human neocortex.

Early corticogenesis was studied in human embryos and early fetuses from Carnegie stages 16 to 22 (5-8 gestational weeks) by using immunohistochemistry for Reelin (Reln), calretinin (CR), and glutamic acid decarboxylase (GAD). A first population of Reln-positive cells appears in the neocortical anlage at stage 16 and increases in number at stages 17-18. At stages 19-20, a monolayer of horizontal CR- and GAD-positive, Reln-negative neurons forms in the preplate, whereas Reln-positive cells shift into a subpial position. Another cell class, the pioneer projection neuron, is CR-positive but GAD- and Reln-negative; pioneer cells contribute early corticofugal axons. Pioneer cells first appear below the monolayer at stage 20 and form a pioneer plate at stage 21. The cortical plate (CP) proper emerges at stage 21 and inserts itself within the pioneer plate, which is thus split into a minor superficial component and a larger deep component that presumably corresponds to the subplate. Initial CP neurons are radially organized and mostly CR-negative. Reln-positive cells remain consistently segregated from the pioneer cells and are thus not directly involved in preplate partition. Our data indicate that the neuronal composition of the human neocortical preplate is more complex than generally described and that various neurons participate in a sequence of events that precede the emergence of the CP.

Calbindin 2↗
PubMed2000

Fetal renal artery flow and renal echogenicity in the chronically hypoxic state.

The object of this study was to investigate the fetal renal arterial blood flow in normal and hyperechogenic kidneys during the third trimester of gestation. The pregnancies screened were all chronically hypoxic. Depending on the etiology of the intrauterine chronic hypoxia, the cases were divided into two study groups. Group I comprised 120 pregnant women with pregnancy-associated hypertension and/or proteinuria. Group II consisted of 87 pregnancies with intrauterine growth retardation. Both study groups included pregnant women from the third trimester. Hyperechogenic renal medullae were detected in 15 out of 120 cases with pregnancy-associated hypertension and/or proteinuria, and in 22 fetuses of the 87 pregnancies involving intrauterine growth retardation. Fetal renal hyperechogenicity appears to be an indicator of fetal arterial circulatory depression, correlated with pathological changes in the resistance index for the fetal renal arteries. The fetal renal arterial blood flow resistance index was significantly lower in hyperechogenic cases. This may also be an in utero indication of subsequent intrauterine and neonatal complications, such as cesarean section because of fetal distress (43%), treatment in a neonatal intensive care unit (51%) or increased perinatal mortality (5.4%, as compared with 0.8-1.0% in the normal population). Detailed ultrasound and Doppler examinations of renal parenchyma and arteries appear to be useful methods in the prenatal diagnosis of reduced renal perfusion and of intrauterine hypoxia to detect possible pathological fetal conditions in utero.

Blood Flow Velocity↗
PubMed1999

[Successful PMA. Review of the activities of the Center for Medically Assisted Procreation of University of Liege, 1985-1997].

Assisted reproductive treatments (ART) hold an increasing place in the field of female infertility but also of male infertility with the development of new micromanipulative technologies. From January 1985 to December 1997, more than 3,000 ovarian punctures were achieved at the CPMA of the University of Liege and more than 40,000 oocytes were recovered. Global results show a take home baby rate of 23% per ovum pick-up and 27% per embryo transfer. Embryo cryopreservation offers an efficient solution to the problem of supernumerary embryos and opens the way for IVF-derived procedures such as oocyte or embryo donation, surrogate mother. The transfer of frozen-thawed embryos increases the total ongoing pregnancy rate per cycle of 31%. One of the aims of our Centre in the near future is the development of new technologies such as control of chromosomal abnormalities or genetic defect in preimplantation embryos and clinical applications of oocyte or ovarian tissue freezing.

Belgium↗
PubMed1999

[Ultrasound in obstetrics and gynecology: 3D ultrasonography].

The first paper concerning the use of ultrasound in soft tissue exploration was published in 1942. From that, following a logarithmic curve, ultrasound has become the main exploration technique in obstetrics and gynecology, essentially due to the absence of side-effect. In obstetrics, a new knowledge of the embryo and the fetus has been obtained. The morphology of the conceptus along the intrauterine life is more precisely defined. The fetal well-being and its metabolic function can be approached by the real time imaging and Doppler application. In gynecology, ultrasound has become the first imaging technique orientations, when mediet, the use of the others.

Embryonic and Fetal Development↗
PubMed1997

Expression of stromelysin-3 in the human placenta and placental bed.

Human placentation is mediated by fetal trophoblastic cells which penetrate into the decidualized uterine endometrium. Trophoblast invasion requires the precisely regulated secretion of specific proteinases able to degrade the endometrial basement membranes and extracellular matrix. To document further the involvement of these proteinases during human placentation, we evaluated in vivo the expression of stromelysin-3, a member of the metalloproteinase family, during the first and third trimesters of pregnancy, by means of immunohistochemistry, in situ hybridization and Northern blot analysis. Human extravillous trophoblasts invading the maternal decidua produced stromelysin-3 during both, the first and third trimesters of pregnancy, but to a lesser extent during the latter. In floating villi, stromelysin-3 expression was restricted to the syncytiotrophoblasts that line intervillous vascular spaces. In conclusion, stromelysin-3 is expressed by differentiated, non-proliferative villous and extravillous trophoblastic cells in early and late placental beds and villi, and its pattern of expression evolves during pregnancy. Our observations suggest that stromelysin-3 could play a role in human placentation.

Blotting, Northern↗
PubMed1995

End-result of routine ultrasound screening for congenital anomalies: the Belgian Multicentric Study 1984-92.

Five ultrasound laboratories from Obstetrics and Gynecology departments of Belgian university hospitals or affiliated institutions conducted a prospective study from 1984 to 1992 in which the results of prenatal ultrasound examinations were compared to examination reports of the neonates. The results of the period 1984-89 (PI) have been published previously, and those of the period 1990-92 (PII) are presented here. Some very minor congenital anomalies, as listed and defined in the EUROCAT Register, were excluded. Of 26,147 pregnant women at normal risk for congenital anomalies, 25,046 had at least one ultrasound scan (96%). A total of 616 fetuses were structurally abnormal (prevalence 2.42%), and 685 abnormalities were recorded. The sensitivity of the ultrasound test was 40.4% in PI and 51.1% in PII for abnormal fetuses (p < 0.05), and 45% (PI) and 64% (PII) for abnormalities (p < 0.01). The specificity was 99.9% and the positive and negative predictive values were 94.2% and 98.6%, respectively; these values did not differ significantly between the two periods. The sensitivity for the detection of anomalies before 23 weeks increased from 21% in PI to 41% in PII, indicating an improvement in the early detection of fetal abnormalities.

Adult↗
PubMed1994

Osteocraniostenosis.

We report a multiple congenital anomalies (MCA) syndrome in three unrelated fetuses consisting of extremely thin, dense, fishbone-like diaphyses, flared metaphyses, mild micromelic dwarfism, brachydactyly, facial dysmorphism, ocular malformations (microphthalmia, aniridia), cloverleaf skull deformity, and splenic hypoplasia. Histopathological investigations showed abnormalities of the metaphyseal cartilage and adjacent diaphyseal ossification, excessive modelling of the metaphyses, and, in one case, dysplasia of the epiphyseal cartilage. We review three previously reported cases. We suggest the name osteocraniostenosis to describe this radiological and clinical disorder, pinpointing its major clinical and radiological features.

Abnormalities, Multiple↗
PubMed1994

Expression of gelatinases A and B and their tissue inhibitors by cells of early and term human placenta and gestational endometrium.

BACKGROUND: Human placentation is mediated by fetal trophoblastic cells that invade the maternal uterine endometrium. Trophoblast invasion requires a precisely regulated secretion of specific proteolytic enzymes able to degrade the endometrial basement membrane and extracellular matrix. EXPERIMENTAL DESIGN: Several studies have documented the key roles of matrix metalloproteinases and their tissue inhibitors in the invasion of various matrices by cultured trophoblasts. In vitro studies suggest that placentation could result from a balance between the secretion of these enzymes by trophoblast cells and their inhibition by the natural tissue inhibitors (TIMPs) produced by maternal decidual cells. The precise localization and levels of expression of these proteins that account for and control invasion during human placentation in vivo however, have not been described. We have evaluated, in vivo, by immunohistochemistry, Northern blot analysis and in situ hybridization, the expression of two metalloproteinases (gelatinases A and B) and their two tissue inhibitors (TIMPs 1 and 2) in placental villi and placental beds of first and third trimesters of normal pregnancy. RESULTS: Human first trimester intermediate trophoblast produced both gelatinases A and B; these two gelatinases were respectively less and no more detected at term in these cells. We found that both TIMP1 and 2 were also expressed in maternal decidual cells with a dramatic increase of TIMP1 at the term of pregnancy. In floating villi, gelatinase A and TIMP1 were localized in the stromal compartment, whereas gelatinase B and TIMP2 were codistributed in trophoblast cells. CONCLUSIONS: The gelatinases A and B and their tissue inhibitors are thus expressed by specific cells in early and late placental beds and villi. This pattern of expression varies during pregnancy. Therefore, our morphologic study supports biologic findings suggesting that these proteins may participate in placentation.

Blotting, Northern↗