Search results for "Chorion"
showing 10 items of 59 documents
The effects of sex hormones, prolactin, and chorionic gonadotropin on pineal electrical activity in guinea pigs.
1981
Microelectrophoretic application of sex hormones onto pineal cells in guinea pigs has shown different responses in pregnant females as compared to males. In pregnant females estrone caused excitation in 74% of the cells tested, while progesterone and testosterone, prolactin, and HCG were inhibitory in a majority of the cells tested, while progesterone and testosterone, prolactin, and HCG were inhibitory in a majority of the cells. In contrast, in males estrone caused excitation of only 19% but inhibition of 37%. A smaller percentage of cells was inhibited by progesterone, while the predominant response to testosterone was excitation. These results suggest that the pineal gland may be under …
Management of undescended testes: European Association of Urology/European Society for Paediatric Urology Guidelines.
2016
Summary Context Undescended testis is the most common endocrinological disease in the male newborn period. Incidence varies between 1.0% and 4.6% in full-term neonates, with rates as high as 45% in preterm neonates. Failure or delay of treatment can result in reduced fertility and/or increased testicular cancer risk in adulthood. Objective To provide recommendations for the diagnosis and treatment of boys with undescended testes which reduce the risk of impaired fertility and testicular cancer in adulthood. Evidence acquisition Embase and Pubmed were searched for all relevant publications, from 1990 to 2015 limited to English language. Data were narratively synthesized in light of methodolo…
The impact of ovarian stimulation on the expression of candidate reprogramming genes in mouse preimplantation embryos.
2012
Ovarian stimulation with gonadotrophins is an integral part of assisted reproductive technologies in human subfertility/infertility treatment. Recent findings have associated ovarian stimulation with the increased incidence of imprinting disorders in humans as well as defects in genome-wide methylation reprogramming and, in particular, imprinting in mice. Here, we present the first study that determined the impact of ovarian stimulation on the expression of developmentally important reprogramming genes <i>(Apex1, Lig1, Lig3, Mbd2, Mbd3, Mbd4, </i>and<i> Polb)</i> in single early mouse morula embryos (16-cell stage). Using absolute quantification of mRNA by quantitati…
Monochorionic twin pregnancy: screening, pathogenesis of complications and management in the era of microinvasive fetal surgery
2010
Objective The management of monochorionic (MC) twin pregnancies varies in different medical centers. This paper compares screening methods to predict the complications of the MC twin pregnancy and different treatment methods. Methods We performed a literature search without language restriction in Cochrane library and PubMed (1970-2009). Case series and cohort screening studies, pathogenesis and management of complications of MC pregnancy were included. Results Elevated risk for intrauterine fetal death (IUFD) and twin-to-twin transfusion syndrome (TTTS) can be detected sonographically. Monitoring of MC pregnancies at increased risk and regular training sessions for the operating team combi…
The type of GnRH analogue used during controlled ovarian stimulation influences early embryo developmental kinetics: a time-lapse study
2013
OBJECTIVE: To explore if the GnRH analogue used for controlled ovarian stimulation (COS) and the ovulation triggering factor (GnRH agonist + hCG triggering versus GnRH antagonist + GnRH agonist triggering) affect embryo development and kinetics.STUDY DESIGN: In a retrospective cohort study in the Instituto Valenciano de Infertilidad (IVI) Alicante and the Instituto Universitario-IVI Valencia, Spain, 2817 embryos deriving from 400 couples undergoing oocyte donation were analysed. After controlled ovarian stimulation and IVF/intracytoplamic sperm injection, the timing of embryonic cleavages was assessed by a video time-lapse system. The results were analysed using Student's t test for compari…
The Immunomodulatory Features of Mesenchymal Stromal Cells Derived from Wharton’s Jelly, Amniotic Membrane, and Chorionic Villi In Vitro and In Vivo …
2016
This chapter focuses on the immunomodulatory properties of placental mesenchymal stromal cells (MSCs) derived from the amniotic membrane, umbilical cord, and chorionic villi. Within the amniotic membrane (AM), we discuss the immunomodulatory properties of the two main cell populations that can be isolated from AM: human amniotic mesenchymal stromal cells (hAMSCs) and human amniotic epithelial cells (hAECs). Within the umbilical cord, several compartments have been described, including the amniotic compartment, the Wharton’s jelly (WJ) compartment, and the vascular and perivascular compartment, but herein attention is focused on the properties of human WJ MSCs (hWJMSCs). Since different isol…
Physiology and Pathology of Ovarian Hyperstimulation Syndrome
2010
Ovarian hyperstimulation syndrome (OHSS) occurs when ovaries primed with follicle-stimulating hormone/leuteinizing hormone (LH) are subsequently exposed to human chorionic gonadotropin (hCG). The ultimate pathophysiological step underlying this clinical picture is increased vascular permeability (VP). With the administration of hCG, the expression vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR-2) mRNA increases significantly rising to a maximum coinciding with peaked VP. Immunohistochemistry shows the presence of VEGF and VEGFR-2 proteins in the granulosa-lutein and endothelial cells of the entire corpus luteum. These findings suggest that the syndrome can be prevented…
Targeting the vascular endothelial growth factor system to prevent ovarian hyperstimulation syndrome
2008
BACKGROUND: Ovarian hyperstimulation syndrome (OHSS) typically occurs when ovaries are primed with FSH/ LH and subsequently exposed to hCG. The ultimate pathophysiological step underlying this clinical picture is increased vascular permeability (VP). METHODS: A search of the literature was carried out using PubMed and the authors’ files. RESULTS: In rodents and humans, the expression of vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR-2) mRNA increases during ovarian stimulation. With the administration of hCG, the expression of each rises to a maximum. Expression of VEGF/VEGFR-2 mRNAs correlates with enhanced VP, with both peaking 48 h following an injection of hCG. Imm…
Optical illusions in scanning electron micrographs: the case of the eggshell of Acrosternum (Chinavia) marginatum (Hemiptera: Pentatomidae)
2003
Scanning electron microscopy revealed that-as is common in this family of the Hemiptera-the eggs of the green stink bug Acrosternum (Chinavia) marginatum are roughly barrel-shaped and possess at their apical pole a row of slender extensions, the aero-micropylar processes. The outer surface of the eggshell carries hexagonally arranged pits. The analysis of cross-fractured eggshells showed that the pits have slender basal extensions with transverse diaphragms. When scanning electron micrographs of the egg surface of A. marginatum are viewed upside down, the perception flips and the pits appear as elevations to all observers addressed. Thus, we are dealing with an optical illusion, which is kn…
Isolated human chorionic vascular reactivity: Technical considerations for fresh preparations
1998
1. 1. Sixty chorionic vascular rings from normal term placentas were immersed in an organ bath for isometric tension recording to study (A) the contractile response to 120 mM of potassium chloride (KCI) after adjustment and equilibration to 1–5 g of passive tension; and (B) the concentration-response curve to KCI after adjustment and equilibration to the optimal passive tension. 2. 2. Adjustment to 4 g of passive tension elicited the maximal (P<0.007) and the latest (P<0.006) KCl-induced contraction among arterial rings. Venous rings showed the greatest contraction when adjusted to 3 g, but the differences were not significant except when compared to 1 g of passive tension (P<0.03). 3. 3. T…