First-trimester determination of fetal gender by ultrasound.
(17/847)
OBJECTIVE: To assess the accuracy of fetal sex determination at 11-14 weeks of gestation. METHODS: Fetal gender assessment by ultrasound was prospectively carried out in 172 singleton pregnancies at 11-14 weeks of gestation immediately before chorionic villus sampling for karyotyping. The genital region was examined in a midsagittal plane and the fetal gender was assigned as male if the angle of the genital tubercle to a horizontal line through the lumbosacral skin surface was greater than 30 degrees and female when the genital tubercle was parallel or convergent (less than 30 degrees) to the horizontal line. RESULTS: The accuracy of sex determination increased with gestation from 70.3% at 11 weeks, to 98.7% at 12 weeks and 100% at 13 weeks. In the male fetuses, there was a significant increase in the angle of the genital tubercle from the horizontal with crown-rump length. Male fetuses were wrongly assigned as female in 56% of cases at 11 weeks, 3% at 12 weeks and 0% at 13 weeks. In contrast, only 5% of the female fetuses at 11 weeks were incorrectly assigned as male and this false-positive rate was 0% at 12 and 13 weeks. CONCLUSION: The clinical value of determination of fetal sex by ultrasound is in deciding whether to carry out prenatal invasive testing in pregnancies at risk of sex-linked genetic abnormalities, because invasive testing would be necessary only in pregnancies with male fetuses. Our results suggest that a final decision on invasive testing for sex-linked conditions should be undertaken only after 12 weeks of gestation. (+info)
Expression and hormonal regulation of the Sox4 gene in mouse female reproductive tissues.
(18/847)
The SOX genes define a family of transcriptional regulators whose diverse patterns and tightly controlled temporal profiles of expression suggest that they play key roles in determination of cell fate during development. One of the family members, Sox4, is expressed in the gonads of adult mice, but expression in the reproductive tissues has not been studied. As previous studies in this laboratory had shown that the SOX4 gene was regulated by ovarian hormones in breast cancer cells, murine Sox4 expression was analyzed in the reproductive tissues of mice by Northern blot analysis and ribonuclease protection assays. Sox4 mRNA expression was detected in the uterus and, at a lower level, in the mammary glands of pubertal and adult mice. Expression was modulated in the uterus of intact mice at various stages of the estrous cycle and was reduced by estradiol treatment of ovariectomized mice. Progesterone treatment partially reversed the estradiol effect. Although no modulation of Sox4 expression in the mammary glands was detected by Northern blot analysis, further evaluation of Sox4 protein expression at a cellular level is required. No modulation of Sox4 levels was observed in the thymus. The results presented here suggest that expression of the Sox4 gene is under ovarian hormone control in the uterus and implicate Sox4 in the complex effects controlled by ovarian hormones in the female reproductive system. (+info)
New approaches for estimating risk from exposure to diethylstilbestrol.
(19/847)
A subgroup from a National Institute of Environmental Health Sciences, workshop concerned with characterizing the effects of endocrine disruptors on human health at environmental exposure levels considered the question, If diethylstilbestrol (DES) were introduced into the market for human use today and likely to result in low-dose exposure of the human fetus, what would be required to assess risk? On the basis of an analysis of the quality of data on human DES exposure, the critical times and doses for inducing genital tract malformations and cancer must be determined. This would be facilitated through analysis of the ontogeny of estrogen receptor expression in the developing human genital tract. Models of low-dose estrogenic effects will have to be developed for human and rodent genital tract development. Mouse models offer many advantages over other potential animal models because of the wealth of the earlier literature, the availability of sensitive end points, the availability of mutant lines, and the possibility of generating genetically engineered model systems. Through multidisciplinary approaches, it should be possible to elucidate the cellular and molecular mechanisms of endocrine disruption elicited by estrogens during development and facilitate an assessment of risk to humans. (+info)
Glycodelin mRNA is expressed in the genital tract of male and female rats (Rattus norvegicus).
(20/847)
In the present study we demonstrate for the first time the expression of glycodelin mRNA in the female and male genital tracts of rats using non-radioactive in situ hybridisation. Glycodelin fragment 1 (+41 to +141) shares 100% homology with the human gene sequence. In the ovary, glycodelin mRNA was restricted to granulosa cells. In the uterus, glycodelin mRNA was expressed in all epithelial cells of the endometrium. In the male reproductive tract, glycodelin mRNA was distributed in all epithelial cells of the epididymis, the prostate and the seminal vesicle. However, in the testis, glycodelin mRNA was predominantly found in spermatogonia and in spermatocytes of the seminiferous epithelium. The expression in several reproductive organs of rats offers an excellent tool to study further the physiological role of glycodelin, which is so far thought to act as an immunosuppressive factor. (+info)
Membrane-bound cell surface peptidases in reproductive organs.
(21/847)
Membrane-bound cell surface peptidases including aminopeptidase-N (EC 3.4.11.2), dipeptidyl peptidases IV (EC.3.4.14.5), carboxypeptidase-M (EC 3.4.17.12), neutral endopeptidase (EC 3.4.24.11) and endothelin converting enzyme-1 (EC 3.4.23) were shown to be differently expressed on human ovarian granulosa, theca interna and luteal cells and on endometrial epithelial and stromal cells. These peptidases have their catalytic sites extracellularly and can metabolize biologically active peptides at the cell surface, serving as local regulators of peptide concentrations. In the ovary and endometrium, numerous peptides are considered to be locally produced and play an important role in the follicular growth, ovulation, corpus luteum function, endometrial differentiation and embryo implantation in an autocrine and/or paracrine fashion. The inhibition of aminopeptidase activity by bestatin affected murine follicular growth, steroidogenesis by porcine ovarian cells and progesterone-induced decidualization of human endometrial stromal cells in vivo or in vitro. These findings suggest that membrane-bound peptidases are important regulators of the function and differentiation of the ovarian cells and endometrial cells including embryo. In the near future, the physiological roles of these peptidases will be clarified and clinical use of peptidase inhibitors may be applied to the various reproductive disorders. (+info)
Multiple developmental roles of VEGF suggested by a LacZ-tagged allele.
(22/847)
Vascular endothelial growth factor (VEGF) is an angiogenic factor and a potent stimulator of microvascular permeability. It is a mitogen specific for endothelial cells. The expression of VEGF and its two receptors, Flk-1 and Flt-1, is pivotal for the proper formation of blood vessels in embryogenesis as shown by gene-targeting experiments. Interestingly, the loss of even a single allele of VEGF led to embryonic lethality between day E9.5 and day E10.5 in the mouse. To assess the role of VEGF during embryonic development we decided to tag VEGF expression with LacZ, by inserting an IRES (internal ribosome entry site)-LacZ reporter cassette into the 3' untranslated region of the gene. This alteration enabled us to monitor VEGF expression throughout embryonic development at single-cell resolution. beta-Galactosidase expression from the altered VEGF locus was first observed prior to gastrulation and was detectable at all stages of vascular development in the embryo. Later, the specific cellular distribution and the level of VEGF expression indicated its pleiotropic role in development. High expression levels seemed to be associated with vasculogenesis and permeability, whereas lower levels were associated with angiogenesis and cell migration. In addition, we found VEGF expression in a subtype of endothelial cells present in the endocardium. We believe that the LacZ-tagged allele we have generated offers a precise means of detecting VEGF expression under a variety of physiological and pathological conditions. (+info)
Identification and characterization of proteins synthesized de novo and secreted by the reproductive tract of the American alligator, Alligator mississippiensis.
(23/847)
The objectives of this study were to identify, characterize and examine differences in proteins synthesized de novo and secreted by different regions of the reproductive tract of the American alligator, Alligator mississippiensis, during three reproductive (vitellogenic, gravid, post-clutch) and one non-reproductive state. After capture, alligators from lakes in north central Florida were anaesthetized, the reproductive tract excised aseptically, the size of any follicle determined, and different functional regions of the tract dissected out and partitioned for explant culture. Analysis of the biosynthetic activity indicated regional variations within the tract, differences among reproductive groups and region by status interactions. When oviductal regions were considered regardless of reproductive status, the greatest incorporation of [3H]Leu into secreted nondialysable macromolecules was by the anterior and posterior infundibulum and oviductal tube compared with the transition zone and the uterus. When status was included, the biosynthetic activity of the anterior and posterior portion of the tract in non-reproductive alligators was not different, whereas that of the posterior region of the reproductive group (vitellogenic, gravid, post-clutch) was significantly lower than that of the anterior region. This finding indicates that regulation of protein synthesis and secretion by the non-reproductive alligator tract is different from that in the tract of the reproductive group. Explant-conditioned media were analysed by one-dimensional and two-dimensional SDS-PAGE and fluorography. Sixteen major proteins in culture media were identified as de novo synthesized, by relative molecular weight, by isoelectric point and by differences in distribution determined for reproductive status and oviductal region. Six proteins were examined by N-terminal amino acid microsequence analysis. On the basis of a 29 amino acid sequence, the major oviductal protein, alligator protein 1 (aP1: M(r) 55,000, basic), found in the infundibulum and tube of vitellogenic alligators, was identical to the major protein isolated from alligator egg albumen. Four proteins (aP4-aP7) were sequenced and shown to be significantly related to immunoglobulin heavy chains from several species. This study demonstrated that a large number of proteins are synthesized de novo and released by the female alligator reproductive tract and that there are biosynthetic activity differences by reproductive status and region. Six proteins have been identified, several of which may be incorporated into alligator egg albumen and some of which appear to be different from proteins found in the egg albumens of other species. (+info)
Differential susceptibility of two species of macaques to experimental vaginal candidiasis.
(24/847)
Vulvovaginal candidiasis (VVC) caused by Candida albicans is a significant problem in women of childbearing age. Unfortunately, protective host defense mechanisms against VVC are poorly understood. Although rodent models of experimental vaginal candidiasis have been useful, several differences from humans limit the correlation of experimental data. The purpose of the present study was to examine two species of macaques as an alternative model of experimental vaginitis. Screening of pig-tailed and rhesus macaques demonstrated that each had mucosal Candida colonization and prior immune sensitization to C. albicans. Vaginal-associated immunity (cytokines, antibodies, and innate resistance) was also detected in cervicovaginal lavage fluid from both species. Nevertheless, intravaginal inoculation of C. albicans into both species, either untreated or under estrogen-treated conditions, resulted in vaginal infection in rhesus, but not pig-tailed, macaques. Several estrogen-dependent changes in the rhesus immune status coincided with susceptibility to infection. Taken together, these results suggest that pig-tailed and rhesus macaques may be useful in studying pathogenesis and immunity associated with C. albicans vaginitis. (+info)