Search results for "Corpus luteum"
showing 10 items of 10 documents
Report on a very young dizygotic human twin pregnancy.
1981
Two ova implanted in one uterus were found at the autopsy of a 28-year-old woman. The ovulation age of both implantations has been estimated to be 10–12 days. The presence of two equally large corpora lutea, one in each ovary, indicates that the implanted ova originated from different ovaries. Thus, an “ovulatio biovarialis” seems to be the basis for the dizygotic twinning in this case. The case is believed to be the only documented example of a very early dizygotic, fraternal pregnancy in humans.
Low-dose dopamine agonist administration blocks vascular endothelial growth factor (VEGF)-mediated vascular hyperpermeability without altering VEGF r…
2006
No specific treatment is available for ovarian hyperstimulation syndrome (OHSS), the most important complication in infertile women treated with gonadotropins. OHSS is caused by increased vascular permeability (VP) through ovarian hypersecretion of vascular endothelial growth factor (VEGF)activating VEGF receptor 2 (VEGFR-2). We previously demonstrated in an OHSS rodent model that increased VP was prevented by inactivating VEGFR-2 with a receptor antagonist(SU5416).However,duetoitstoxicity(thromboembolism) and disruption of VEGFR-2-dependent angiogenic processes critical for pregnancy, this kind of compound cannot be used clinically to prevent OHSS. Dopamine receptor 2 (Dp-r2) agonists, use…
Reproductive Biology Including Evidence for Superfetation in the European Badger Meles meles (Carnivora: Mustelidae)
2015
The reproductive biology of the European badger (Meles meles) is of wide interest because it is one of the few mammal species that show delayed implantation and one of only five which are suggested to show superfetation as a reproductive strategy. This study aimed to describe the reproductive biology of female Irish badgers with a view to increasing our understanding of the process of delayed implantation and superfetation. We carried out a detailed histological examination of the reproductive tract of 264 female badgers taken from sites across 20 of the 26 counties in the Republic of Ireland. The key results show evidence of multiple blastocysts at different stages of development present s…
Posters Early pregnancy P01First trimester normograms for a wide variety of ultrasound, hemodynamic and serum parameters
2000
Background The aim of the study was to assess prospectively the evolution of multiple clinical parameters throughout the first trimester of pregnancy. Method A transvaginal ultrasound examination and a blood test was weekly performed until the 13th gestational week in a group of healthy volunteers. A total of 25 spontaneously conceived singleton pregnant women with good pregnancy outcome finally completed the study. The evolution of 10 transvaginal ultrasound parameters, 5 Doppler measurements and 6 serum parameters was studied. Results An increasing trend with advancing gestation was evident for the mean gestational sac (MSD) and amniotic sac (AS) diameters, trophoblastic rim, CRL and seru…
Does transvaginal color Doppler sonography differentiate between developing and involuting ectopic pregnancies?
1995
The objective of this study was to assess the addition of transvaginal color Doppler imaging to transvaginal ultrasonography and beta-human chorionic gonadotropin values to differentiate between developin and involuting ectopic pregnancies. Forty surgically confirmed ectopic pregnancies were classified into developing or involuting according to histopathologic findings. Results were compared retrospectively with the plasma beta-human chorionic gonadotropin values as well as the resistive index and pulsatility index obtained in corpora lutea and peritrophoblastic flow in serial examinations. Student's t-test was used for comparison of means. Logistic regression analysis was applied to predic…
Paracrine dialogue in implantation
2002
We know that the implantation process requires a functionally normal embryo at the blastocyst stage and a receptive endometrium, but also a communication link between them is needed. This paracrine dialogue between the embryo, endometrium and the corpus luteum are known to occur in ruminants and primates, more specifically endometrial-embryonic interactions have been reported in rodents and primates but not in humans. This process is a highly regulated mechanism and many molecules take part in this cross-talk. Here, we present updated information in humans on the embryonic regulation of endometrial epithelial molecules such as chemokines, adhesion and anti-adhesion molecules, and leptin dur…
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…
Interleukin-1β (IL-1β) Is a Modulator of Human Luteal Cell Steroidogenesis: Localization of the IL Type I System in the Corpus Luteum1
1999
The present investigation examined the effect of interleukin-1beta (IL-1beta) on progesterone production by human luteal cells and the expression and localization of the IL-1 system in the human corpus luteum (CL). Luteal cells were isolated from corpora lutea collected throughout the luteal phase. After dispersion, luteal cells were treated with a panel of monoclonal antibodies directed to leukocyte-specific molecules. The leukocytes were isolated with immunomagnetic beads. Leukocyte-free luteal cells exhibited greater steroidogenic responsiveness to hCG toward the end of the luteal phase. The treatment of mixed luteal cells (total luteal cells) with IL-1beta inhibited by 60% hCG-stimulate…
Embryo effects in human implantation: embryonic regulation of endometrial molecules in human implantation.
2001
: Embryonic implantation requires coordinated development of the blastocyst and the maternal endometrium. Considerable advances have been made in the understanding of the cell biology of human embryo and maternal endometrium as separate entities. Nevertheless, communication between them and their reciprocal effects on each other constitute an exciting and as-yet unsolved problem in reproductive medicine. Cross-talk among the embryo, endometrium, and the corpus luteum are known to occur in ruminants and primates; more specifically, endometrial-embryonic interactions have been reported in rodents and primates. Here, we present updated information in humans on the embryonic regulation of endom…