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Biomedical subjects

P Merviel

Publications and source records attributed to P Merviel.

53 records · Page 3Linked to original sources

[Oocyte fertilizability and embryo development in poor responders].

Oocyte quality (atresia, immaturity), fertilizability, the incidence of abnormal fertilization (parthenogenesis, triploidy) and embryo development (rate of division and morphology) are similar in poor and normal responders. Only, the small number of available embryos (0.9/patient vs 4.4) penalize these patients.

Adult↗

[Role of microbiopsies in the therapeutic and diagnostic approach in cases of mammary microcalcification: preliminary results].

The increase of mammographies has lead to the discovery of more frequent mammary microcalcifications. Presently, about 30% of breast tumors are discovered from infraclinics lesions. Instead of the different classifications, the microcalcifications are the omnious sign with bad specificity. It is in the aim to improve the diagnostic etiology and the choice of therapy, that the directed microbiopsies on microcalcifications had been realized. After an orthogonal location and under local anesthesia, we performed at least six biopsies with a 2.1 mm (14 gauge) needle. This allowed recovery of malignant lesions during the control of microcalcifications and permitted considerable early operative treatment. In fact, a diagnostic and therapeutic advancement of 12 months as compared to a clinical diagnosis, permitting a 30% reduction of metastasis.

Adult↗

[Arterial hypertension and pregnancy].

Hypertension is observed in 10 to 15% of pregnancies, but only 10% of affected women will suffer preeclampsia. The pathophysiology of preeclampsia is based on an early anomaly of placental implantation, leading to a cascade of events (secretion of vasopressive prostaglandins, anomalies of hemostatis) which can cause disseminated intravascular coagulation. The diagnosis of preeclampsia is based on hypertension and significant proteinuria (above 0.5 g/24 h), and paraclinical maternal and fetal examinations to follow the evolution and detect the appearance of maternal complications (retroplacental haematoma, Hellp syndrome and eclampsia) and (or) fetal complications (delayed growth, in utero fetal death, perinatal death). The aim of hypertensive treatment is to normalise blood pressure and to avoid maternal complications. Preventive treatment with aspirin reduces the frequency of recurrent preeclampsia and delayed growth of the fetus.

Female↗

Normal human endometrial cells in culture: characterization and immortalization of epithelial and stromal cells by SV 40 large T antigen.

Thirty endometrial biopsies were cultured in order to separate stromal and epithelial cells. Using epidermal growth factor (EGF), cortisol, cholera toxin, insulin with 5% horse serum for epithelial cells or a medium with 20% fetal calf serum for stromal cells, we could specifically enrich endometrial culture in epithelial or stromal cells and culture them for 1 or 2 months. These cultures retained the phenotypic characteristics of epithelial (cytokeratins, mucin HMFG 1) and stromal (vimentin, smooth muscle actin, desmin) lineage by immunostaining analysis. Epithelial and stromal cultures from one individual were respectively immortalized by the SV 40 large T antigen. The immortalized cell lines kept the phenotype of the normal cells from which they derived.

Actins↗

[Epithelial and stromal cell culture of human endometrium and characterization].

Endometrium is a heterogeneous tissue, subject to many factors of which the actions and the regulations on the different cellular types were unknown. A medium with cortisol, cholera toxin, EGF, insulin and low concentration of horse serum is used for epithelial cell primary cultures (range 23-55 days, mean: 31.9 days). A medium with high concentration of fetal calf serum is used for stromal cell primary cultures (range 21-214 days, mean: 75 days). We have characterized by immunocytochemical studies all different cultures.

Adult↗

Treatment of progressive systemic sclerosis by plasma exchange: long-term results in 40 patients.

The efficacy of plasma exchanges (PE) during the course of scleroderma has only been investigated for short periods. The aim of this study was to follow patients over a long enough period to observe the course of the clinical and paraclinical symptoms in the short, medium, and long term. Forty patients, 24 women and 16 men, were treated by PE and observed for 1-3, 3-12 and over 12 months. Immunological, biological and clinical course and any undesirable side effects were evaluated using a detailed questionnaire. Concomitant therapies were reported and most frequently consisted of corticosteroids, colchicine, factor XIII or vasodilators (nifedipine, captopril). The therapeutic effectiveness of PE was assessed on the basis of improvements in cutaneous, digestive, joint, muscular, lung, cardiovascular and renal lesions. Our findings confirmed the effectiveness of short-term PE on scleroderma (52% of the patients improved during the first 3 months). However, this improvement was transient (5% improvement between 3 and 12 months and only 2.5% over 12 months) and limited to the cutaneous and muscular lesions. Thus, PE cannot be recommended for the treatment of progressive systemic sclerosis.

Adolescent↗

Prenatal diagnosis of a congenital bladder diverticulum. Case report and benefits of prenatal diagnosis.

A case of congenital bladder diverticulum diagnosed at 37 weeks of gestation (measured from the first day after the last day of the last menstrual period) is reported. Delivery took place 24 h later. A postnatal urologic work-up confirmed the diagnosis of asymptomatic congenital bladder diverticulum. The infant underwent laparotomic surgery at the age of 6 months, with an extravesical diverticulectomy and ureteral reimplantation. There were no complications. This is the first case reported in the literature of a prenatal diagnosis of a congenital bladder diverticulum. This new aspect allows early management and avoidance of the diagnostic meanders to which the discovery of a pelvic mass might lead, as well as the complications that can follow bladder diverticula.

Adult↗

Fetal impact of cholestasis of pregnancy: experience at Tenon Hospital and literature review.

Cholestasis of pregnancy is a liver disorder that occurs during the second half of pregnancy, causing pruritus and elevated serum bile acid levels. Its etiology remains unknown but probably involves vascular and humoral immune responses, mediated by bile acids. This disorder is associated with substantially increased fetal morbidity and mortality. The most satisfactory treatment consists in delivering the fetus as soon as pulmonary maturation has occurred.

Adult↗

Fetal-placental and decidual-placental units: role of endocrine and paracrine regulations in parturition.

In primates, fetal adrenal and placental steroidogenic enzymatic systems are complementary in a fetal-placental unit, synchronizing fetal maturation and myometrial activation in late gestation. Moreover, as hemochorial placentation characterizes rodents and primates, paracrine regulations between decidua and placenta are essential to the immunotolerance of the conceptus and its development. Thus, the decidual-placental unit remains in a striking state of decidual quiescence throughout gestation, and the reversal of this quiescence is thought to play a key role in myometrial stimulation and the onset of parturition. A comprehensive view of the control of myometrial contractility, through the interaction of paracrine and endocrine modifications in late gestation, is proposed. The failure of these mechanisms underlie prematurity and the use of fetal therapy in threatened preterm labor.

Animals↗

The role of integrins in human embryo implantation.

Integrins are adhesion molecules present in endometrial, decidual, and extravillous cytotrophoblast (EVCT) cells. They participate in cell-cell adhesion as well as in adhesion between cells and components of the extracellular matrix, and they play an important role in the endometrial phenotype change that occurs during the secretory phase, the first stage of implantation. At the beginning of pregnancy, the change in integrin expression is synchronized with the trophoblast attachment (embryo-endometrium interactions with integrins alpha(v)beta3, alpha4beta1, alpha6beta1, and alpha7beta1) and the embryo's invasion of the decidua (integrins alpha6beta4-->alpha5beta1-->alpha1beta1-->alpha4beta1 switch from proliferative to endovascular EVCT). Several diseases, including preeclampsia, intrauterine growth retardation caused by vascular problems and defective luteal phases, may be explained by anomalies in integrin patterns.

Cell Adhesion Molecules↗

[Indications for intracytoplasmic sperm injection: possible influence of oocyte quality on the results].

Intracytoplasmic sperm injection is theoretically the first line treatment of many forms of severe male infertility, but the prognostic factors are to be determined according to the indications. Thus the results of two clinical teams working with the same biological Unit show statistically different pregnancy rates per oocyte pick-up (15.9% versus 35.7% - p < 0.02) and per transfer (16.9% versus 34.9% - p < 0.03). They could by explained by female factors such as age and ovarian response to stimulation, which probably have influence on embryonic quality.

Cytoplasm↗

[Aspirin during pregnancy. Indications and modalities of prescription after the publication of the later trials].

Aspirin, an inhibitor of cyclo-oxygenase, is prescribed in a number of conditions related to abnormal production of prostaglandins including gravidic hypertension. Results of the most recent trials demonstrate that in patients with a past history of pre-eclampsia or intra-uterine growth retardation, a pathological Doppler examination of the uterus, a pathological angiotensin test or an antiphospholipid syndrome, prescription of aspirin at the dose of 100 mg/day can prevent recurrence or development of pre-eclampsia or intra-uterine growth retardation. Treatment should begin as soon as possible during pregnancy, certainly before development of clinical manifestations. After history taking and identification of possible contraindications, bleeding time (Ivy method) is recorded before and after prescription and should be lower than 8 minutes. In case bleeding time exceeds 10 minutes 10 to 15 days after initiating aspirin, doses may be reduced to 50 mg per day or even 50 mg every two or three days to reach the target level. Treatment should generally be continued up to 36 weeks gestation.

Angiotensin II↗

[Oocyte maturation and intracytoplasmic sperm injection].

Intracytoplasmic sperm injection (ICSI), treatment of severe male infertility allows an accurate evaluation of oocyte maturity at recovery after corona-cell removal. In cycles comprising a GnRH analog desensitization and a stimulation by hMG or FSH, 12% of oocytes aspirated from follicles (> 14 mm), 34 hours post-hCG are still immature, in prophase or metaphase 1. They are able to achieve meiosis in vitro in 66% of the cases and will be fertilized (2 PN) by ICSI in 51% of the cases as the in vivo mature oocytes of the same cohort. Nevertheless, the quality of cytoplasmic maturation and consequently of embryonic viability remains to be assessed as there still are few pregnancies arising from in vitro matured oocytes. ICSI also represents the only way to obtain normal fertilization in some exceptional but observed anomalies of oocyte maturation, particularly when there is a lack of zona reaction leading to repetitive polyspermy in conventional IVF.

Adult↗