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V Tsatsaris

Publications and source records attributed to V Tsatsaris.

At least 19 recordsLinked to original sources
PubMed2006

PPARs and the placenta.

The discovery of the peroxisome proliferator-activated receptors (PPARs) in 1990s provided new insights in understanding the mechanisms involved in the control of energy homeostasis and in cell differentiation, proliferation, apoptosis and the inflammatory process. The PPARs became thus an exciting therapeutic target for diabetes, metabolic syndrome, atherosclerosis, and cancer. Unexpectedly, genetic studies performed in mice established that PPARgamma are essential for placental development. After a brief description of structural and functional features of PPARs, we will summarize in this review the most recent results concerning expression and the role of PPARs in placenta and of PPARgamma in human trophoblastic cells in particular.

Animals↗
PubMed2006

Human chorionic gonadotropin expression in human trophoblasts from early placenta: comparative study between villous and extravillous trophoblastic cells.

Human trophoblast differentiates into two pathways: extravillous cytotrophoblasts (EVCT) that invade the uterus wall and villous cytotrophoblasts (VCT) that fuse to form the syncytiotrophoblast (ST) involved in placental exchanges and endocrine function. It is established that hCG is produced and secreted by the ST into the maternal compartment where it plays a key endocrine role and stimulates ST formation in an autocrine manner. Herein, we investigated hCG expression in early placentas by immunohistochemistry using different antibodies. We then compared hCG secretion by primary cultures of VCT and EVCT isolated from the same first trimester human chorionic villi. In situ hCG was immunodetected in EVCT all along their invasive differentiating pathway except in cells near the stromal core of the proximal column. hCG expression was confirmed in vitro by immunocytochemistry and hCG secretion quantified in cell supernatants. Interestingly, whereas hCG secretion increased during VCT differentiation into ST (from 60 to 350UI/L/microg DNA), EVCT secretion remained constant and at a high level during the same culture period (160UI/L/microg DNA). Our data demonstrated that in addition to the ST, invasive EVCT also expressed and secreted high levels of hCG, suggesting a specific paracrine and/or autocrine role for hCG from EVCT origin.

Animals↗
PubMed2006

[Quality of anonymous delivery procedures: analysis of practices and ethical issues].

OBJECTIVES: The purpose of this study was to assess implementation of procedures for anonymous delivery and also to determine the awareness of the medical team. MATERIAL AND METHOD: We reviewed retrospectively all deliveries performed in a Paris maternity ward during the years 2000-2003 where the mother requested application of the anonymous procedure. A questionnaire was also addressed to all physicians and midwives in the same institution in order to evaluate their knowledge of the procedures available and their point of view. RESULTS: Among the seventeen deliveries examined, the anonymous procedure was not completely fulfilled for 11 since the name of the mother could be identified. The quality of the files depended on the date at which the decision to use the anonymous procedure was made: delivery was more anonymous when the decision was made at the first consultation, less so when made later. The questionnaires revealed that professionals lacked information and were insufficiently aware of the procedures available. CONCLUSION: It appears useful to establish a standard procedure in order to better protect the parturient's wishes and comply with French law (4 March 2002). This point is particularly important since at the infant's majority, he/she may request access to personal information contained in the medical file.

Adult↗
PubMed2005

Expression of HERV-W Env glycoprotein (syncytin) in the extravillous trophoblast of first trimester human placenta.

Although the extravillous trophoblastic invasion has a critical role in human placental development, nothing is known about HERV-W expression in the extravillous phenotype. The aim of the present study was to localize in first trimester placenta the expression of HERV-W Env glycoprotein and its receptor all along the differentiation pathway of the extravillous phenotype. In addition using an in vitro model of extravillous cytotrophoblastic cell isolation and invasion we investigated the presence of HERV-W transcripts and envelope glycoprotein in cultured extravillous trophoblastic cells. Using monoclonal and polyclonal antibodies, the glycoprotein was immunolocalized in all the cell types of the extravillous phenotype lineage: cytotrophoblastic cells of the column, interstitial extravillous trophoblastic cells, multinucleated giant cells and endovascular trophoblast. Furthermore, using a polyclonal antibody, the D mammalian virus receptor was also localized in the various extravillous trophoblastic phenotypes. In addition, the presence of HERV-W transcripts and protein was demonstrated in cultured extravillous trophoblastic cells. HERV-W Env glycoprotein expressed in villous and extravillous trophoblast can be considered as a specific marker of the human trophoblast.

Adult↗
PubMed2004

[Magnesium sulfate in obstetrics: current data].

OBJECTIVE: To review the available evidence regarding history, pharmacology, physiology, maternal/fetal side effects, and efficacy of magnesium sulfate in pregnant women. DATA SOURCES: The literature in Medline was searched from 1966 through April 2003 using the terms "magnesium sulfate," "tocolytic," "preeclampsia," "eclampsia," and "pregnancy." Reviews of bibliographies of retrieved articles provided additional references. RESULTS: Magnesium sulfate (MgSO4) has long been used for prophylaxis of preterm delivery (tocolytic affect) and eclampsia prophylaxis (neuroprotective effect). Randomized controlled trials and systematic reviews have demonstrated the efficacy of magnesium sulfate in preventing eclampsia in patients with preeclampsia or in patients with eclampsia. Whether magnesium sulfate should be administered to patients with severe preeclampsia or to mild preeclampsia is discussed in the manuscript. Inversely, it appears that magnesium sulfate is ineffective in delaying birth or preventing preterm birth when it is used as a tocolytic. Furthermore, there is evidence that high cumulative doses of magnesium sulfate may be associated with increased infant mortality. CONCLUSION: The evidence to date confirms the efficacy of magnesium sulfate therapy for women with eclampsia and preeclampsia. However, magnesium sulfate should not be used in order to treat preterm labor.

Adult↗
PubMed2004

[Prenatal risk evaluation, parent information and mode of delivery].

Perinatal networks, antenatal administration of glucosteroids, postnatal administration of surfactant, and new techniques for mechanical ventilation, have considerably improved the prognosis of extremely preterm infants. Such recent progress in perinatology had enabled neonatologists to provide intensive care for infants born after 24 and 28 weeks of gestation. This practice raises serious medical and ethical issues. The optimal mode of delivery of such newborns is not well established mainly because available studies are retrospective and subjected to biases. Moreover, perinatologists are implicated in the continuing discussion on ethical issues that modify clinical practices.

Birth Weight↗
PubMed2004

[Extremely preterm infants: resuscitation criteria in the delivery room and dialogue with parents before birth].

The resuscitation of extremely preterm infants presents complex medical, social and ethical issues for the families and the health professionals. The principle of a systematic resuscitation "temporary intensive care" does not prohibit the question of a limit in terms of gestational age and birth weight. In France, a do not resuscitate order (comfort care alone) is appropriate for newborns weighing less than 500g and/or with a gestational age of less than 24 weeks' since the mortality is nearly 100%. The survival of infants born at 24 weeks' gestational age remains low with significant risks of chronic medical problems and neurodevelopmental disabilities. The decisions regarding the extent of resuscitative efforts depend on antenatal factors, condition of the neonate at birth and the parental opinion. Before the delivery, parents should receive appropriate information about survival and risks of adverse long-term outcome. The physician should follow the parents' desires whenever the parents' decision would not obviously violate the infants' best interests. However, they must be informed that decisions about neonatal management made before the delivery can have to be changed in the delivery room, depending on the condition of the neonate at birth. At 25 weeks of gestational age, the prognosis is better and the resuscitation should be more intensive.

Gestational Age↗
PubMed2002

Prenatal diagnosis of bilateral isolated fetal hyperechogenic kidneys. Is it possible to predict long term outcome?

OBJECTIVE: To study perinatal and long term outcome following prenatal diagnosis of hyperechogenic kidneys. DESIGN: Prospective observational cohort study. SETTING: The Maternité Port-Royal Hôpital Cochin and at the Departments of Obstetrics and Paediatric Nephrology, Necker Enfants Malades in Paris, France. POPULATION: Forty-three fetuses with isolated bilateral hyperechogenic kidneys. METHODS: All patients referred with isolated bilateral hyperechogenic fetal kidneys were followed up prospectively up to 34-132 months. The following prenatal items were analysed: fetal kidney size, amniotic fluid volume, gestational age at diagnosis, family history and renal ultrasound in parents. Postmortem examination was carried out in cases with perinatal death. Postnatal follow up of survivors included postnatal ultrasound, blood pressure, serum creatinine, proteinuria, need for restricted diet, weight and height and renal biopsy when available. MAIN OUTCOME MEASURES: Aetiology of hyperechogenicity, perinatal mortality and renal function in survivors. RESULTS: The aetiology could be established by family history, postmortem or postnatal data, but not by prenatal ultrasound. There were 20 autosomal recessive, 8 autosomal dominant polycystic kidney diseases, 9 other renal disorders and 6 symptom-free survivors without aetiological diagnosis. There were 19 terminations of pregnancy, 5 neonatal deaths and 19 survivors, of whom 14 had normal renal function three had mild and two had end stage renal failure. None of those with severe oligohydramnios and fetal kidneys > 4 SD survived (n = 14, 10 terminations and 4 neonatal deaths), whereas of the 17 with normal amniotic fluid volume and kidneys < 4 SD, 14 survived, of whom 9 were symptom-free. CONCLUSION: Aetiology could not be established prenatally in the absence of familial data. Kidney size and amniotic fluid volume were the best prenatal predictors of outcome.

Cohort Studies↗
PubMed2002

[Which tocolytic drugs in case of preterm labor?].

Because criteria used for the prediction of preterm labor are poorly effective, many patients receive tocolytic therapy in excess during pregnancy. Beta-mimetic agonists are the reference tocolytic drugs in most countries. Their efficacy in prolonging pregnancy compared to a placebo is proven although no benefit in neonatal morbidity or mortality has been demonstrated. Beta-mimetics have many contraindications, and side-effects are frequent. Serious complications such as pulmonary edema and maternal deaths, though rare, have been reported. Recent research has focused on tocolytic drugs with similar efficacy to beta-mimetics but with less side effects. Calcium-channel-blockers and oxytocin antagonists have been compared with beta-agonists in randomized trials. Both have demonstrated similar efficacy in the prolongation of pregnancy for at least 48 hours. Contrary to beta-mimetics, very few interruptions of treatment have been observed with these treatments. Other tocolytic drugs such as cyclooxygenase inhibitors, although effective in prolonging pregnancy, have unacceptable fetal side effects. Progesterone, antispasmodic drugs and magnesium sulfate have been widely used but their efficacy has not been demonstrated. More recent treatments such as NO-donors and cyclooxygenase-II specific antagonists are not sufficiently evaluated. In conclusion, three main classes may be used as first line tocolytic therapy, beta-adrenergic agonists, calcium-channel-blockers, and oxytocin antagonists. The choice among these treatments may be based on contraindications to beta-mimetics, side-effects of the treatment, or even economic reasons.

Clinical Trials as Topic↗
PubMed2001

Balloon replacement of fetal membranes to facilitate emergency cervical cerclage.

BACKGROUND: Emergency cerclage can be used in cases of cervical incompetence, even when fetal membranes bulge through the dilated cervix. To facilitate the procedure we used a balloon device to replace the fetal membranes. TECHNIQUE: With the patient in a steep Trendelenburg position, after epidural anesthesia, the fetal membranes were replaced into the uterine cavity with an inflated balloon of the type used for endoscopic preperitoneal dissection. Cervical cerclage was done by the McDonald technique. EXPERIENCE: We have done 25 emergency cerclages with this technique. The following maternal and perinatal outcomes were assessed retrospectively: age, medical history, gestational age at inclusion and delivery, cervical dilatation at admission, preterm rupture of membranes, clinical or histologic chorioamnionitis, birth weight, admission to the neonatal intensive care unit, neonatal death, and postnatal course. CONCLUSION: Replacing prolapsed fetal membranes with an inflated balloon is a convenient technique that allows gestation to be prolonged for an average of 31 days. Cerclage was feasible when the cervix was widely dilated (more than 4 cm); it was associated with prolongation of gestation by a median of 9 days.

Emergencies↗
PubMed2001

Tocolysis with nifedipine or beta-adrenergic agonists: a meta-analysis.

OBJECTIVE: To clarify the relative efficacy of nifedipine and beta-agonists for tocolysis. DATA SOURCES: The literature was searched in the following databases: MEDLINE 1965-1998, Embase 1988-1998, Current Contents 1997-1998, and the Cochrane Database for 1998. We also sought unpublished trials and abstracts submitted to major international congresses. Search terms were: "tocolysis," "nifedipine," "calcium channel blocker," "ritodrine," "terbutaline," and "salbutamol." METHODS OF STUDY SELECTION: Randomized controlled trials comparing tocolysis with nifedipine and beta-adrenergic agonists during preterm labor were reviewed. In cases with postrandomization exclusions, authors were contacted to obtain intent-to-treat results and to avoid analytical bias. We identified 11 published and two unpublished randomized trials. TABULATION, INTEGRATION, AND RESULTS: Data were extracted by two reviewers and analyzed by a blinded biostatistician with RevMan 3.1 software from the Cochrane Collaboration. We analyzed nine relevant randomized controlled trials that included 679 patients. Meta-analysis showed that nifedipine was more effective than the beta-agonists in delaying delivery at least 48 hours [odds ratio (OR) 1.52, 95% confidence interval (CI) 1.03, 2.24], or over 34 weeks (OR 1.87, 95% CI 1.11, 3.15). The agents did not differ as to the incidence of deliveries after 37 weeks (OR 1.29, 95% CI 0.85, 1.96) or the neonatal mortality rate (OR 1.51, 95% CI 0.63, 3.65). Treatment with nifedipine was interrupted significantly less often because of side effects (OR 0.12, 95% CI 0.05, 0.29) and led to better neonatal outcomes (fewer infants with respiratory distress syndrome: OR 0.57, 95% CI 0.37, 0.89) or transferred to neonatal intensive care units (OR 0.65, 95% CI 0.43, 0.97). CONCLUSION: With respect to neonatal outcome, nifedipine appears to be more effective than beta-agonists for tocolysis and should be considered for use as a first-line tocolytic agent.

Adrenergic beta-Agonists↗
PubMed2001

[The new tocolytics].

Explore the source record for details and available documents.

Calcium Channel Blockers↗
PubMed2001

[Which tocolytics should be used in 2001?].

Beta-mimetics are the gold standard tocolytic treatment but raise several problems. Despite their recognized efficacy in prolonging pregnancy, the neonatal benefit remains to be proven. There are several contraindications and frequent adverse effects, with a risk of fatal maternal accidents. The lack of reliable criteria for the prediction of preterm birth leads to giving unnecessary treatments to two-thirds of the patients. In this context, obstetrical practices have tended to prefer tocolytics which, with the same efficacy, would have fewer side effects than beta-mimetics and which would not raise a risk of severe complications. Calcium-channel blockers belonging to the dihydropyridin family and ocytocin antagonists would appear to meet the new requirements. In randomized trials versus beta-mimetics, they have been found to have a comparable effect in prolonging pregnancy by 48 hours. Tolerance is better than with beta-mimetics and treatment interruption due to side effects can be avoided. Finally, a meta-analysis of trials comparing calcium inhibitors versus beta-mimetics demonstrated a decrease in respiratory distress syndrome in the neonates and a reduction in the number of transfers to neonatal intensive care. The data accumulated on these new compounds would appear to suggest that they should be used as the first line treatment and not as an alternative to beta-mimetics. Other compounds including NO donors and cyclo-oxygenase 2 inhibitors are under evaluation.

Adrenergic beta-Agonists↗
PubMed2001

[Tocolysis with calcium-channel-blockers].

OBJECTIVE: To evaluate the use of calcium-channel-blockers (CCBs) for tocolysis. METHODS: We reviewed the literature retrieved from the Medline database from 1967 to 200 dealing with fetal toxicity and efficacy of CCBs compared with beta-adrenergic agonists. RESULTS: Data on fetal toxicity in animals were inconsistent. A teratologic effect has been observed during early pregnancy at supratherapeutic dosage. At usual therapeutic dosage, no fetal abnormalities have been observed. The efficacy of CBs for tocolysis is superior to that of beta-adrenergic drugs and allows a reduction of neonatal morbidity. Calcium channel blockers are better tolerated than beta-adrenergic agonists. CONCLUSION: Published data suggest that CCBs could be used a first line tocolytic agents. Although use of CCBs is extremely simple, they should not be prescribed in low-risk outpatients.

Adrenergic beta-Agonists↗
PubMed2000

Place of amniocentesis in the assessment of preterm labour.

OBJECTIVE: To evaluate the benefits and indications for amniocentesis in cases of preterm labor with or without preterm rupture of membranes. METHOD: A review of the literature on amniocentesis in cases of intra-amniotic infection. RESULTS: Amniocentesis is an invasive method that allows the diagnosis of intra-amniotic infection. However, no randomized trials have been performed from which we can assess the benefits and complications of amniocentesis in preterm labor. CONCLUSION: The published data do not justify the routine practice of amniocentesis in preterm labor. More data are needed to evaluate the benefits and complications of this practice. Only randomized trials of patients in preterm labor, comparing those who undergo amniocentesis with those who do not, will clarify the indications for this procedure.

Amniocentesis↗