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PubMed1988

An experimental study of tubo-ovarian function following restoration of patency in hydrosalpinges.

The recovery of tubal function after restoration of patency in mechanically induced hydrosalpinges was studied in twenty sexually mature rabbits by correlating the morphological lesions of tubal damage and adhesion formation with the ovulatory function, pregnancy rate and nidation index at 2 and 4-8 weeks postoperative intervals. Two weeks after hydrosalpinx correction no implantations occurred although the oviducts had a patency rate of 63% and no or slight adhesions were present. From four weeks after hydrosalpinx correction implantations occurred. Morphological studies showed a partial or complete recovery of mucosal lesions in this group of rabbits. The number of ovulations correlated with the presence or absence of a moderate degree of postoperative adhesion formation.

Animals↗
PubMed1995

Molecular identification of steroid analogs with dissociated antiprogestin activities.

Antiprogestins of the 11 beta-aryl-substituted 19-norsteroid family are effectively used in inhibiting nidation and in terminating pregnancies. They are potentially useful in the treatment of progesterone-related diseases such as meningiomas and endometriosis and in inhibiting the growth of mammary tumors. However their long-term use is limited because of their inherent antiglucocorticoid activity. Here we have used molecular biological techniques to examine the antiglucocorticoid activity of a series of antiprogestins. The compounds we have analyzed contain different substituents at the C-17 position and a change from the trans to cis configuration of the C-D steroid rings. Our results show that minor changes at the C-17 position but not in the configuration of the C and D rings produced antiprogestins with reduced antiglucocorticoid activity. Thus only subtle changes in the structure of classical antiprogestins are needed for the reduction of their antiglucocorticoid activities.

Androgen Receptor Antagonists↗
PubMed1992

Progesterone antagonists: tumor-inhibiting potential and mechanism of action.

A new approach for the treatment of breast cancer could be the use of progesterone antagonists. These compounds were originally developed for the inhibition of progesterone-dependent processes and have been shown to be effective in inhibition of nidation and interruption of pregnancy. Although the roles of progesterone and the progesterone receptor in control of cell growth remain unclear, it was found in progesterone receptor positive mammary carcinoma cell lines that the antiprogestin, Mifepristone, had an inhibitory effect on cell growth and a growth-inhibiting action on the DMBA-induced mammary carcinoma of the rat. We have shown that the progesterone antagonists, Onapristone and ZK 112993, which possess a reduced antiglucocorticoid activity compared to Mifepristone, exert a strong tumor-inhibiting effect in a panel of hormone-dependent mammary tumor models. The effects of these compounds were in some systems superior to those of tamoxifen or high dose progestins and comparable to ovariectomy. Although prerequisites for their antiproliferative potency are an affinity to the progesterone receptor as well as a sufficient number of available receptors in the tumors, the strong tumor inhibiting potential of the antiprogestins cannot be explained by a classical anti-hormonal mechanism. Surprisingly, the antitumor activity is evident in spite of elevated serum levels of ovarian and pituitary hormones. It was established by morphometric procedures that treatment with Onapristone triggers differentiation of the mitotically active polygonal tumor epithelial cell towards secretory active glandular structures and acini. All our quantitative light and electron microscopic data indicate that the antitumor action of antiprogestins is accompanied by the initiation of terminal differentiation leading to (apoptotic) cell death. Finally, our flow cytometry studies revealed an accumulation of the tumor cells in the G0G1 phase of the cell cycle, which may result from induction of differentiation since a differentiation-specific G1 arrest has already been proposed for other stem cell systems. It can be concluded from these data that the progesterone receptor antagonists differ in their mode of action from compounds used in established endocrine treatment strategies for mammary carcinoma. The ability of progesterone antagonists like Onapristone to reduce the number of cells in S-phase may offer a significant clinical advantage, since it is established that the S-phase fraction is a highly significant predictor of disease-free survival among axillary node-negative patients with diploid mammary tumors.

Animals↗
PubMed2003

Immunohistochemical localization of leukemia inhibitory factor, interleukins 1 and 6 at the primary implantation site in the rhesus monkey.

Blastocyst implantation and placentation involve localized inflammatory type of responses at and around the site of nidation. In the present study, the likely involvement of inflammatory cytokines, namely, leukemia inhibitory factor (LIF), interleukins 1 alpha and 1 beta (IL-1alpha and IL-1beta) and IL-6 at the primary implantation site of the rhesus monkey was examined immunocytochemically during lacunar (n=6) and villous (n=8) stages of gestation. Trophoblast cells and extraembryonic mesenchymal cells were immunopositive for LIF and IL-1alpha. The distribution of IL-1beta and IL-6 in trophoblast cells was low in lacunar stage samples, however, a higher degree of immunopositivity for IL-6 was observed in villous stage samples. Decidual cells were immunopositive for all the cytokines studied. In lacunar stage samples, plaque cells adjacent to implanted nidus were immunopositive for all the cytokines examined, and the degree of their immunoprecipitation increased, except that of IL-1beta, during the villous stage. Luminal and glandular epithelial cells were immunopositive for LIF, IL-1alpha, IL-1beta and IL-6 in lacunar and in villous stage samples. LIF immunopositivity was detected in endothelial cells of blood vessels within and below chorionic plate and cytotrophoblast shell, while vascular smooth muscle cells were positive for all the cytokines studied. The temporo-spatial characteristics of LIF, IL-1alpha, IL-1beta and IL-6 protein expressions in primary implantation sites of the rhesus monkey suggest that these pro-inflammatory cytokines play specific roles in regulating trophoblast cell proliferation, differentiation, invasion and associated maternal tissue remodelling during early gestation.

Animals↗
PubMed2006

What is the preimplantation embryo?

We present results from our 'bioethical field studies', which explore and compare the views of experts, patients and the general public on the beginning of human life and the status of the preimplantation embryo in Germany. Using a qualitative and quantitative multi-method approach, we found crucial differences in the categorization of the beginning of human life within the expert group (representative samples of human geneticists n=104, ethicists n=168, midwives n=294, obstetricians n=147, paediatricians n=166), and between expert and lay samples (IVF couples n=108, high genetic risk couples n=324, general population n=1017). The majority of lay respondents as well as paediatricians and obstetricians chose nidation, the moment when the implantation of the fertilized egg into the uterus takes place, as the crucial boundary that marks the beginning of human life, whereas the majority of (female) human geneticists, ethicists and midwives voted for conception as the decisive point in time. The views of all groups on the status of the preimplantation embryo differed from the assumptions underlying German legislation (Embryo Protection Act). Religiousness and religious affiliation, gender, attitudes towards disabled people, post-material values and a present desire for a child were identified as independent factors influencing attitudes towards the preimplantation embryo in the population sample. The results are discussed within a broader philosophical and social science perspective of constructivism versus essentialism, proposing a truly interdisciplinary approach to such bioethical core issues as new reproductive technologies and the status of the preimplantation embryo.

Adolescent↗
PubMed1999

Temporal and cell-specific gene expression by human endometrium after coculture with trophoblast.

OBJECTIVE: Our purpose was to identify temporal and stage-specific expression of endometrial genes during coculture with trophoblast cells. STUDY DESIGN: Endometrial stromal cells were cultured to confluence in the presence of estradiol and progesterone. During these culture conditions the gene expression of 1 tissue specimen that secreted abundant prolactin (415 ng/mL culture medium at 21 days) was compared with a second specimen that did not. These 2 tissues were coincubated with trophoblast tissue in a specialized coculture flask. After 4 and 24 hours of culture messenger ribonucleic acid was extracted and reverse transcribed, and the complementary deoxyribonucleic acid products were amplified by polymerase chain reactions. The reverse transcriptase-polymerase chain reaction products were separated by electrophoresis, and potentially important complementary deoxyribonucleic acid fragments were reamplified, inserted into a plasmid vector, and sequenced after recovery. Sequences were submitted for Basic Local Alignment Search Tool searches of GenBank. RESULTS: We observed up-regulation of 6 gene fragments in decidualized endometrium after 4 hours of coculture with choriocarcinoma-derived trophoblast BeWo cells, but only 1 gene fragment was up-regulated after 24 hours of exposure. Conversely, 2 fragments were down-regulated in decidualized stroma that was exposed to BeWo for 4 hours and 2 fragments were underexpressed after the 24-hour exposure. In the parallel experiment stromal cells that failed to secrete prolactin did not elicit the same regulation of expression. The nondecidualized endometrium overexpressed 1 gene fragment after 4 hours of BeWo exposure and overexpressed 4 gene fragments after exposure to BeWo for 24 hours. Underexpression of gene products also occurred with the nondecidualized endometrium, and we observed 2 fragments and 1 fragment to be underexpressed after 4 and 24 hours of BeWo exposure, respectively. To date, 3 of the candidate differential display fragments from these experiments have been cloned and sequenced. An up-regulated fragment (C6225J4EB-1) was 99% identical (167/168 sequences) to a reported nonredundant expressed sequence tags isolated from muscle, brain, ovary, testis, liver, and pregnant uterus tissues. A second up-regulated fragment (C4375J4EB-1) matched 100% identity (117/117) with a reported gene fragment in the expressed sequence tags database of GenBank that was derived from fetal heart and pregnant uterus. Additional characterization of these expressed sequence tags has not been reported. The third up-regulated fragment (C4250J24EB-2) was 100% identical (265/265) to human reduced nicotinamide adenine dinucleotide dehydrogenase III in the nonredundant gene database of GenBank. CONCLUSION: This report demonstrates the potential usefulness that endometrial-trophoblast coculture and differential display can offer for the molecular analysis of implantation phenomena. We have recognized both overexpression and underexpression of interesting gene fragments during the early phases of endometrial responses to paracrine regulators derived from BeWo trophoblast cells. These responses appear to be specific to the degree of endometrial transformation (decidualization) before challenge by the trophoblast and to the duration of the BeWo exposure. Sequence data identified 1 gene with an unidentified function, another gene with a known function, and a fragment not previously recognized. We submit that our model of endometrial-trophoblast coculture offers a novel tool to test cellular responses during implantation, and differential display represents a sensitive technique that can identify many of the important elements of genomic signaling during nidation.

Coculture Techniques↗
PubMed1986

Disruption of pregnancy in mouse by aristolic acid: I. Plausible explanation in relation to early pregnancy events.

Aristolic acid (AA), obtained from Aristolochia indica Linn, disrupted nidation in mice when administered on Day 1 of pregnancy. The implantation inhibiting effect of the compound was assessed with respect to certain parameters which are characteristics of early pregnancy, such as tubal transport of ova into the uterus, hyperpermeability of the endometrial capillaries, increase in uterine weight and total protein content, endometrial bed preparation and changes in uterine phosphatase enzymes during Days 4-6 of pregnancy. The compound did not affect tubal transport of eggs, but the uterine blue reaction, caused by extravasation of the dye, pontamine blue, at future implantation sites was inhibited significantly in treated mice. Histological picture of the uterus revealed AA-induced impairment of development (i.e. decidualization) and reconciled with decreases found in uterine weight and its total protein contents in treated animals. In control untreated mice, specific uterine alkaline phosphatase (ALP) activity increased significantly from Days 4 through 6 of pregnancy, but this was prevented in treated mice. On the other hand, specific uterine acid phosphatase (AP) activity was high on Day 5, while in treated mice uterine AP activity remained low during Days 4 and 5 and increased significantly thereafter. It was inferred that AA interferes with steroidal conditioning of the uterus and renders it hostile to ovum implantation.

Acid Phosphatase↗
PubMed1998

Synthesis and in vitro and in vivo evaluation of dopaminergic ergoline derivatives.

A series of ergoline-amides was synthesised in the discovery of new dopaminomimetic agents. Several compounds exhibited in vivo high prolactin lowering activity (indirectly measured by the nidation test) in rats. For the most active, the potential anti-Parkinson activity was evaluated by observation of the contralateral turning behaviour in 6-OH-DA lesioned rats. The acute toxicity by oral route in mice was also studied.

Animals↗
PubMed1998

Synthesis and antihypertensive activity of 2,4-dioxoimidazolidin-1-yl and perhydro-2,4-dioxopyrimidin-1-yl ergoline derivatives.

The synthesis and antihypertensive activity of a series of 2,4-dioxoimidazolidin-1-yl and perhydro-2,4-dioxopyrimidin-1-yl ergoline derivatives are reported. The oral antihypertensive activity was studied in spontaneously hypertensive rats (SHRs) by measuring systolic blood pressure by an indirect tail-cuff method at different times after treatment. The prolactin lowering activity (indirectly measured by the nidation test) in rats and the oral acute toxicity in mice were also studied. The results of this study revealed potent antihypertensive ergoline derivatives devoid of side-effects related to the dopaminergic stimulation and the importance of the delta 9,10 double bond for conferring high potency within these compounds.

Animals↗
PubMed1975

Neutrophils and the mechanism of IUD action in rats.

Current research on the mechanism of action of the IUD has focused on a local, low-grade endometritis in preventing blastocystic implantation. With rabbit antisera to rat neutrophils, a neutropenic state was induced in rats having a silk suture in one uterine horn. Assay for nidation sites in the severely polymorphdepleted rats revealed no implantation sites in the IUD horn and an average of 5.8 sites in the control horn, suggesting that inflammation plays a relatively minor role, if any, in the mechanism of action of the IUD.

Agranulocytosis↗
PubMed1975

Biologic effects following active immunization with delta 5-3 beta-hydroxysteroid dehydrogenase.

Immunization of female rats with crude preparations of delta 5-3 beta-hydroxysteroid dehydrogenase combined with complete Freund's adjuvant resulted in suppression of the endogenous enzyme activity in the ovarian interstitial tissue and the corpora lutea. As a result, estrous cyclicity, nidation, or maintenance of pregnancy was adversely affected in proportion to the level of the antibody to the enzyme following the series of immunizations. On the basis of the biologic response, it can be assumed that progesterone synthesis was reduced as a result of neutralization of enzyme action in the ovary by the formation of antibodies to the delta 5-3 beta-hydroxysteroid dehydrogenase. Further studies are required to verify this assumption.

3-Hydroxysteroid Dehydrogenases↗
PubMed1981

Fertility and tubal morphology after microsurgical removal of segments of the porcine fallopian tube.

A controlled study was carried out in the pig to determine the effect on fertility of resecting either the ampullary-isthmic junction or the isthmus. In both treated groups, the nidation index was lower than that in the control animals. The index was not significantly lower in the isthmic resection group than in the ampullary-isthmic junction group. The implications of these findings in terms of fallopian tube physiology and human tubal reconstructive surgery are discussed.

Animals↗
PubMed1983

Histology and fertility after microsurgical anastomosis of the rabbit fallopian tube with nylon and polyglactin sutures.

Polyglactin and nylon suture material were compared in microsurgical anastomosis of oviduct of rabbits with regard to the histologic reaction, adhesion formation, and nidation index. Thirty days after surgery, the tissue inflammatory response was very similar in both groups. At 90 days, polyglactin had been totally absorbed in 80% of the cases, and no inflammatory reaction persisted at the site of the suture. At this time, multinucleated giant cell reaction to nylon sutures was persistent but minimal. The results reveal no significant functional differences between oviduct reanastomosed with nylon versus polyglactin suture. No significant difference in subsequent fertility due to suture selection was demonstrated.

Animals↗
PubMed1986

Primary and secondary closure of ampullary salpingotomy compared in the rabbit.

Because there is disagreement as to how linear ampullary salpingotomy should heal, primarily or secondarily, we compared the two methods with the use of rabbit oviducts in which conditions simulating ectopic pregnancy had been induced. Pregnancy rates (86% versus 75%), nidation indices (62% versus 54%), and percentage of adhesion-free tubes (50% versus 32%) were greater after primary closure, but these differences were not statistically significant. Ampullary tuboperitoneal fistulae occurred at the site of operation in 6.8% of tubes and impaired fertility (P less than 0.005).

Animals↗
PubMed1992

The impact of embryonic development and endometrial maturity on the timing of implantation.

OBJECTIVE: To gain insight into the peri-implantation period in the human and to answer the question whether timing of nidation is dependent on the stage of embryonic development, endometrial maturation, or a possible dialogue between the two. DESIGN: Seventy-five women underwent embryo transfer (ET) throughout 93 cycles. Thirty-three ETs resulted in viable pregnancies and deliveries. These pregnancy cycles were used for embryonic signal detection. Embryos of identical age were transferred onto hormonally and histologically defined endometria of different maturational stages (days 15 to 19). Human chorionic gonadotropin (hCG) was measured by a hypersensitive chemiluminescence assay in maternal serum every 1 to 5 days to detect the first embryonic signal. RESULTS: Individual linear regressions of hCG versus embryonic age and endometrial maturation were performed on 33 viable pregnancy cycles (r2 = 90.5% to 99.9%, P less than 0.02 to 0.002). First signal detection was restricted to an embryonic age of 7.1 +/- 0.28 (mean +/- SD) days (range 6.6 to 7.4) irrespective of endometrial maturation. The pattern of hCG detection was triphasic, described by a sigmoidal curve with the maximal slope corresponding to an hCG doubling time of 15.9 hours. Embryo transfers on cycle day 19 had a steeper slope of hCG detection than days 15 and 16 (P less than 0.05). CONCLUSIONS: First embryonic signal detection (presumed window of implantation) extends between cycle days 20 and 24. Implantation is dependent on embryonic age and is independent of endometrial maturation within this window. The timing and sigmoidal pattern of hCG detection coincides with structural changes of the implantation bed. The steeper slope of late ETs may represent a compensatory mechanism for late maternal recognition of pregnancy for corpus luteum rescue.

Blastocyst↗
PubMed1996

Achieving multiple-order embryo transfer identifies women over 40 years of age with improved in vitro fertilization outcome.

OBJECTIVE: To define factors in patients > or = 40 years that may improve outcome and provide prognosis for success in IVF-ET. DESIGN: Retrospective. SETTING: University infertility center. PATIENTS: Patients (n = 501) undergoing IVF-ET from 1987 to 1994. INTERVENTIONS: IVF-ET (n = 713 cycles) with GnRH-analogue suppression and hMG stimulation. MAIN OUTCOME MEASURES: We evaluated data including age, diagnosis, prestimulation (day 3) FSH and E2, hMG ampules used, days of monitoring, follicle number and size, maximum E2, ova retrieved, cancellation rate, clinical pregnancy, nidation, and miscarriage rates. RESULTS: Overall, patients > or = 40 years had significantly decreased pregnancy rates (PRs), response to stimulation, and increased miscarriage rates. However, if these patients had four or more embryos transferred, their response and PRs (34.4% per ET) were not significantly different from younger women (47.7% per ET). The majority (77.8%) of pregnancies in women > or = 40 years occurred when four or more embryos were transferred. CONCLUSION: A subset (49%) of women > or = 40 years undergoing IVF-ET will respond to ovarian stimulation well enough to result in four or more embryos available for transfer with a resultant PR similar to that observed in younger patients. We recommend consideration of an attempt at IVF-ET before recommending oocyte donation.

Adult↗
PubMed1997

Successful pregnancy in a 63-year-old woman.

OBJECTIVE: To report the occurrence of an unusual case of successful pregnancy achieved by oocyte donation in a woman > 60 years of age. DESIGN: Case report. SETTING: University-based assisted reproductive technology program. PATIENT(S): Sixty-three-year old nulligravida, married for 16 years to her 60-year-old husband. Throughout her infertility treatment, the patient was believed to be 10 years younger, as she claimed. She revealed her true age of 63 only upon being referred for obstetric care at 13 weeks of gestational age. INTERVENTION(S): Oocyte donation, IVF, embryo cryopreservation, and ET. MAIN OUTCOME MEASURE(S): Attainment of pregnancy and subsequent delivery. RESULT(S): The patient underwent two cycles of oocyte donation. During the second attempt, the fresh transfer resulted in a clinical miscarriage at approximately 8 weeks of gestational age. A subsequent transfer of three frozen-thawed embryos resulted in an ongoing singleton gestation. The pregnancy was complicated by gestational diabetes (controlled by diet) and mild pregnancy-induced hypertension. Delivery by cesarean section at 38 weeks of gestational age resulted in the birth of a healthy female infant weighing 2,844 g with Apgar scores of 9 and 9. CONCLUSION(S): This case demonstrates that the uterus is capable of supporting nidation and subsequent gestation for many years beyond natural menopause. It shows that other aspects of human physiology are capable of adapting to the stresses and changes of pregnancy sufficiently well to achieve a normal birth at the age of 63 years. This case also exemplifies the difficulty in attempting to regulate the age of recipients in oocyte donation. As in other aspects of human life, when age limits are applied to the provision of certain services, human beings whose age falls outside of these limits become motivated to deceive the providers of those services to avail themselves of the services.

Breast Feeding↗
PubMed1994

Morphometry of implantation in sheep. I. Trophoblast attachment, modification of the uterine lining, conceptus size and embryo location.

The degree of trophoblastic attachment, modification of the uterine lining epithelium during implantation, possible differences in size of the conceptus, and preferential zones of nidation were evaluated. Eight ewes at 14 (n=3), 17 (n=2), 20 (n=1), and 24 (n=2) d of gestation were used, and 6 to 8 equidistant samples of either uterine o uterine plus embryonic membranes tissues were taken from each uterine horn for histomorphometric analysis. Trophoblastic attachment varied from 1.5 to 100% at 14 and 24 d of gestation, respectively. Modification of the uterine lining epithelium ranged from 0% at 14 d to 90% at 24 d. The conceptuses occupied a variable area of the uterine cavity; 15.1% at 14 d, 100% at 17 d, 70.6% at 20 d and 100% at 24 d of gestation. All the embryos were located caudal to the center of the uterine horn. Attachment of the trophoblast and modification of the uterine lining epithelium occurred in the area surrounding the embryos. Implantation was a gradual and long-lasting process which commenced near the embryo and extended peripherally. Morphological variations need to be considered when evaluating embryonic viability.

Journal Article↗