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Fertilized Ovum (fertilized + ovum)
Selected AbstractsFunctions of corticotropin-releasing hormone in anthropoid primates: From brain to placentaAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 4 2006Michael L. Power Corticotropin-releasing hormone (CRH) is an ancient regulatory molecule. The CRH hormone family has at least four ligands, two receptors, and a binding protein. Its well-known role in the hypothalamic-pituitary-adrenal (HPA) axis is only one of many. The expression of CRH and its related peptides is widespread in peripheral tissue, with important functions in the immune system, energy metabolism, and female reproduction. For example, CRH is involved in the implantation of fertilized ova and in maternal tolerance to the fetus. An apparently unique adaptation has evolved in anthropoid primates: placental expression of CRH. Placental CRH stimulates the fetal adrenal zone, an adrenal structure unique to primates, to produce dehydroepiandrosterone sulfate (DHEAS), which is converted to estrogen by the placenta. Cortisol induced from the fetal and maternal adrenal glands by placental CRH induces further placental CRH expression, forming a positive feedback system that results in increasing placental production of estrogen. In humans, abnormally high placental expression of CRH is associated with pregnancy complications (e.g., preterm labor, intrauterine growth restriction (IUGR), and preeclampsia). Within anthropoid primates, there are at least two patterns of placental CRH expression over gestation: monkeys differ from great apes (and humans) by having a midgestational peak in CRH expression. The functional significance of these differences between monkeys and apes is not yet understood, but it supports the hypothesis that placental CRH performs multiple roles during gestation. A clearer understanding of the diversity of patterns of placental CRH expression among anthropoid primates would aid our understanding of its role in human pregnancy. Am. J. Hum. Biol. 18:431,447, 2006. © 2006 Wiley-Liss, Inc. [source] Spontaneous twin cervico-isthmic pregnancy in a grand multiparous womanJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 5 2010Meral Cetin Abstract Cervico-isthmic pregnancy is a rare form of ectopic pregnancy and is defined as the implantation of a fertilized ovum in the cervico-isthmic portion. The cause is unknown; local pathology related to previous cervical or uterine surgery may play a role, given an apparent association with a prior history of curettage or cesarean delivery. Transvaginal ultrasonography and ,-human chorionic gonadotrophin assays are useful for diagnosis. Here we report a case of spontaneous twin cervico-isthmic pregnancy in a grand multiparous patient who was diagnosed early in the first trimester with transvaginal ultrasonography. The pregnancy was terminated successfully with methotrexate. Methotrexate seems to be most successful at early gestational ages. [source] Tubal ectopic pregnancy associated with an adenomatoid tumorPATHOLOGY INTERNATIONAL, Issue 3 2001Teruhiko Inoue We present a case of coexistence of an ectopic pregnancy and an adenomatoid tumor in the same fallopian tube. The adenomatoid tumor is the most common benign neoplasm of the fallopian tube, and the vast majority of ectopic pregnancies occur in the fallopian tube. However, coexistence of these two conditions is extremely rare, and there has been only one previously reported case in the English literature. In the present case, the placental tissue, consisting of chorionic villi and decidua, was present in the ampulla, and the adenomatoid tumor was found in the myosalpinx, just proximal to the implantation site, replacing a large part of the myosalpinx. The close spatial relationship of these two lesions suggests that an adenomatoid tumor could have interfered with transportation of the fertilized ovum through the tube, possibly via impaired contractile activity of the myosalpinx, and consequently caused the ectopic tubal pregnancy. [source] Anti-DNA Antibodies Cross-reacting with Laminin Inhibit Trophoblast Attachment and Migration: Implications for Recurrent Pregnancy Loss in SLE PatientsAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2000FAISAL QURESHI PROBLEM: Systemic lupus erythematosus (SLE), an autoimmune disease, is associated with reduced fetal survival, recurrent abortions, and other pregnancy complications. Some of the autoantibodies found in SLE bind to laminins (LNs), which play an important role in the implantation of the fertilized ovum in humans. METHOD OF STUDY: To elucidate the role of these specific autoantibodies, chorionic villous explants from 6,7-week-old human placentas were established as organ cultures on laminin-1 (LN-1), collagen IV (CN-IV) or uncoated culture dishes. The cultures were then exposed to a mouse monoclonal anti-DNA/anti-LN-1 antibody, to human polyclonal lupus antibodies cross-reacting with LN-1, a function-blocking polyclonal antibody to LN-1, polyclonal antibodies to CN-IV, or IgG control. RESULTS: The explants attached to LN-1 and CN-IV, but not to uncoated culture dishes. LN-1 promoted migration of trophoblast, whereas CN-IV promoted migration of fibroblast-like cells. Trophoblast attachment and migration were abolished in a dose-dependent manner by all three antibodies to LN-1, but not by antibodies to CN-IV or IgG control. Furthermore, the effect of anti-LN antibodies was abolished by preincubating them with LN-1. CONCLUSIONS: These studies suggest that anti-DNA antibodies cross-reacting with LNs may play a role in early pregnancy failure in SLE patients by interfering with placental implantation. [source] | ||||||||||