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PubMed2001

Purification and characterization of an immunomodulatory endometrial protein, glycodelin.

Human glycodelin is synthesized by endometrial cells in the late secretory phase and early pregnancy under hormonal regulation. Whereas the precise physiological functions of glycodelin are unknown, its expression during embryonic nidation and its inhibition of T cell proliferation suggest an immunomodulatory role. We purified human glycodelin from first trimester human decidual cytosol by using a rapid two-step high-performance liquid chromatography method and investigated its effects on human monocyte migration. Human U937 cells were used as a model of monocyte chemotaxis in Boyden chamber migration assays. N-Formyl-Met-Leu-Phe and the beta-chemokine RANTES (regulated on activation normal T cell expressed and secreted) were used as monocyte chemoattractants. Purified glycodelin inhibited monocyte migration in a dose-dependent fashion (IC50 = 550 nm). Glycodelin activity was totally reversed by heat inactivation (95 degrees C x 15 min) and neutralized by pretreatment with specific anti-glycodelin antibodies. Deglycosylated glycodelin was equipotent to intact glycodelin in the monocyte migration assay. 125I-Glycodelin binding to whole U937 cells revealed a single, saturable site with a Kd = 48 +/- 21 nm by Scatchard analysis. Cross-linking studies indicated that glycodelin binds to a high molecular mass (approximately 250 kDa) protein complex at the monocyte cell surface. Our findings support the hypothesis that glycodelin reduces the local maternal inflammatory response toward the implantation of a semiallogeneic conceptus.

Amino Acid Sequence↗
PubMed1988

Detection of unknown early pregnancy. A matter of safety.

Almost 2% of females admitted as accident victims to a general hospital-teaching facility were pregnant without their physicians knowing it. Emergency treatment of such patients may overshadow other aspects of holistic care and have adverse consequences when a pregnancy is unrecognized. These cases illustrate the importance of always performing a complete physical examination and obtaining a good history that includes menstrual data. When appropriate, we recommend routine use of the serum human chorionic gonadotropin test for pregnancy. It is a simple and reliable means of detecting pregnancy by ten days after nidation, and its use protects the patient, physician, and unborn child. Safer health service is the result.

Accidents, Traffic↗
PubMed1991

Reproductive outcome after ovarian surgery: suturing versus nonsuturing of the ovarian cortex.

The purpose of this study was to ascertain if microsurgical approximation of the ovarian edges after ovarian surgery alters postoperative results, as determined by both adhesion formation and reproductive outcome. Sixteen female white New Zealand rabbits were anesthetized, and the ovaries were exposed. Each ovary was longitudinally bivalved with a scalpel, but only one ovary was reconstructed microsurgically, whereas the contralateral ovary was left open. Four weeks after surgery, the rabbits were mated, and two weeks later, a laparotomy was performed to evaluate postoperative adhesions, the number of corpora lutea in each ovary, and the number of embryos in each uterine horn. The nidation index was calculated. No significant differences were found between the microsurgically sutured and the nonsutured ovaries for all the parameters evaluated. Our data suggest that not closing the ovarian incision does not alter either postoperative adhesion formation or reproductive outcome.

Animals↗
PubMed1991

Reproductive outcome after ovarian surgery: microsurgery versus CO 2 laser.

The present study was undertaken to compare CO 2 laser vs microsurgery in ovarian surgery, evaluating both postoperative adhesion formation and reproductive outcome. Eighteen female white New Zealand rabbits were anesthetized, and the ovaries were exposed. At random, one ovary was longitudinally bivalved with a scalpel and then reconstructed by microsurgery. The contralateral ovary was similarly cut, but with a CO 2 laser set at a superpulsed mode. Four weeks after surgery, the rabbits were mated, and two weeks later, the animals were evaluated for extent of postoperative adhesion formation, number of corpora lutea in each ovary, and number of embryos in each uterine horn. The nidation index was calculated. The present study shows no difference in postoperative adhesion formation or reproductive function following ovarian surgery by microsurgery or CO 2 laser.

Animals↗
PubMed1995

Rabbit fallopian tube reanastomosis using a microvascular stapling device.

The 3M Precise Microvascular Anastomotic System (MAS), a microvascular stapling device, was compared with microsurgery for the reanastomosis of rabbit fallopian tubes. Differences in operative time, tubal patency, adhesion formation, and fertility rate were studied in 18 rabbits. Only 17% of tubes repaired by MAS were subsequently patent by chromopertubation, compared with 72% with microsurgery. Mean nidation indices were 0.05 for MAS and 0.22 for microsurgery. Sixty-one percent of adnexae repaired by MAS were adhesion stage I, whereas 83% of microsurgically repaired adnexae were stage I. Mean operative time was 28.2 min for MAS vs 21.6 min for microsurgery. Only the differences in patency rate and operative time were statistically significant, but the trends suggest that fallopian tube reanastomosis by MAS offers no advantage over conventional microsurgical technique.

Animals↗
PubMed1989

Brain life and brain death: a proposal for a normative agreement.

This paper reviews moral and cultural assessments which led to the definition of brain death and calls for a similar normative consensus regarding the moral recognition and legal protection of embryonal life related to criteria of brain life. This paper differentiates between cortical brain life I, i.e., the first existence of post-mitotic stationary neurons forming the early cortical plate (54th day post conception), and cortical brain life II, i.e., the beginning of cortical neuro-neuronal synapses (after the 70th day p.c.). The latter are preconditional for establishing the communicative network within the cortex and with subcortical structures. The paper conservatively calls for a tentative moral consensus that could recognize brain life I, i.e., the 54th day p.c., as a stage prior to which embryo research generally would be acceptable in accordance with principles similar to those which led to the acceptance of brain death. Other developmental stages such as fertilization, nidation, viability, as well as the 'potentiality' principle are less significant for the moral recognition of early human life.

Beginning of Human Life↗
PubMed1995

Endogenous plasma growth hormone and the occurrence of pregnancies in patients undergoing in-vitro fertilization and embryo transfer with ovarian stimulation.

This study was undertaken to investigate a possible relationship between endogenous secretion of growth hormone (GH) during ovarian stimulation and treatment outcome in patients undergoing in-vitro fertilization (IVF) and embryo transfer. Plasma samples obtained from 19 women who had successfully completed all stages of IVF/embryo transfer were analysed retrospectively. Based on the increase in GH during treatment, 11 GH responders and eight GH non-responders were identified. Mean daily GH concentrations for the GH responders and GH non-responders were 3.5 +/- 1.8 and 1.8 +/- 0.8, 5.4 +/- 2.3 and 0.5 +/- 0.2, and 9.0 +/- 1.9 and 0.7 +/- 0.1 ng/ml (P < 0.05) for days 10, 11 and 12 respectively. Plasma insulin-like growth factor-I slightly increased with treatment in both groups. No significant difference between these groups was found in relation to treatment duration, number of human menopausal gonadotrophin ampoules used, oestradiol peak values, and number of oocytes retrieved or fertilization rate. Seven of the 11 GH responder women conceived in comparison with one pregnancy among eight GH non-responder patients (P < 0.05). In view of the absence of differences in the clinical and laboratory parameters, we suggest that the occurrence of pregnancies among GH responder patients might be related to a positive local effect of GH or its mediators on uterine receptivity at the time of nidation.

Adult↗
PubMed1988

Morphology and fertility after re-anastomosis of the rabbit fallopian tube with fibrin glue.

Morphology and fertility were studied in 20 female New Zealand White rabbits after re-anastomosis of the Fallopian tube with fibrin glue and conventional microsurgical techniques. All oviducts were patent postoperatively. No intraperitoneal adhesions were observed. There were no significant differences with regard to the number of corpora lutea, implantations and the nidation index. Morphological studies demonstrated a normal fold pattern and ciliation at the side of anastomosis in the sealed oviducts as well as in the sutured oviducts. No intraluminal fibrin deposits were found. For re-anastomosis of the Fallopian tube with fibrin glue, splinting is necessary. In some instances this may be related to a mucosal trauma. However, under optimal conditions the use of fibrin glue is equivalent to conventional microsurgical anastomosis of the oviduct. For tubocornual, ampullary--ampullary and isthmic--ampullary anastomoses with luminal disparity, fibrin glue seems to be inappropriate.

Adhesives↗
PubMed1988

Transfer of pre-embryos donated and fertilized in vivo to recipients given a steroid replacement therapy.

This study describes eleven procedures of non-surgical recovery of preimplantation conceptuses from the uteri of eight fertile donor women and the transfer of the recovered pre-embryos into the uteri of infertile recipients with primary ovarian failure, or with hypothalamic--pituitary failure. Conjugated oestrogens and progesterone were administered to recipients as replacement steroids during the first 20 weeks of pregnancy, in order to produce a secretory endometrium allowing nidation and development of the transferred conceptuses. Five pre-embryo transfers resulted in two viable pregnancies and one early abortion. Non-surgical pre-embryo transfer is a simple and practical method for providing donated ova to women lacking efficient ovarian function.

Adult↗
PubMed1989

Results of IVF attempts in patients with unexplained infertility.

From January 1986 to July 1987, 143 patients with unexplained infertility (UI) following 217 IVF attempts were studied and randomly assigned for statistical analysis to be compared with 434 tubal infertility (TI) patients undergoing 748 IVF attempts. The age of patients, previous pregnancy history and stimulation protocols were identical in both groups. In comparison with tubal patients, IVF attempts on the UI group were characterized by the same rates of cycle failure, mean number of oocytes retrieved per cycle, a lower fertilization rate (45.7% UI/59.8% TI) (P less than 0.01) and no difference in cleavage and nidation rates. However, a decrease in the pregnancy rate/attempt (13.8% UI/19.5% TI) tended towards a significant value (P = 0.06). Although the semen parameters were found to be in the normal range during the previous fertility screening in both groups, the incidence of at least one abnormality (count less than 20 X 10(6)/ml, and/or total motility less than 30% and/or abnormal forms greater than 75%) on the day of insemination was found to be significantly higher in UI (20%) than in TI (11%) patients. Moreover, 25% of UI patients did not fertilize any oocytes inseminated, whatever the number of oocytes retrieved. This rate of failed fertilization was significantly lower (9%) in tubal patients. The oestrogen response profiles were similar in both groups, analyzed according to the stimulation protocols.(ABSTRACT TRUNCATED AT 250 WORDS)

Buserelin↗
PubMed1991

Characterization of the steroid-dependence of insulin-like growth factor-binding protein-2 synthesis and mRNA expression in cultured human endometrial stromal cells.

The insulin-like growth factors (IGF-I and -II) are believed to be important in endometrial differentiation and blastocyst nidation, and proteins that regulate IGF action (IGF-binding proteins, IGFBPs) are hormonally regulated in endometrium during the menstrual cycle. To characterize further steroid-dependence of the IGFBPs, we established endometrial stromal cells in culture in the absence and presence of oestradiol (E2) and progesterone (P) and examined the conditioned medium for IGFBPs by Western ligand blot analysis. Stromal cells constitutively synthesized IGFBP-3, IGFBP-2, a 27 kd, and a 24 kd IGFBP. In the presence of E2 and P, a 10- to 15-fold increase in IGFBP-2 was detected in the conditioned medium beginning after about 7 days in culture, when cells decidualized and steroid-mediated prolactin secretion began. Withdrawal of steroids resulted in a marked decrease in IGFBP-2, comparable to control levels, and cells increased their IGFBP-2 production when rechallenged with E2 and P. Total RNA was isolated from stromal cells, and Northern blot analysis using a cDNA probe specific for IGFBP-2 revealed differential expression of a 1.4 kb mRNA transcript in steroid-treated compared to control cells. The effects of progestational agents alone on IGFBP synthesis was also examined. Progesterone, medroxyprogesterone acetate and norethindrone all stimulated IGFBP-2 synthesis 12- to 15-fold compared to controls, and a progesterone receptor antagonist, RU 486, blocked the stimulatory effect of progesterone. IGFBP-2 synthesis was increased two-fold above controls by 17-alpha-hydroxyprogesterone, and RU 486 alone and hydrocortisone were without effect. Identification of IGFBP-2 in conditioned medium was made using IGFBP-specific antiserum. These data show that (a) endometrial stromal cells synthesize and secrete IGFBP-2, (b) IGFBP-2 protein synthesis is controlled by steroid hormones, (c) P, by interacting with its receptor, modulates IGFBP-2 synthesis and (d) expression of IGFBP-2 mRNA is controlled by sex steroids.

Autoradiography↗
PubMed1992

Fibrin glue for reanastomosis of the fallopian tube in the rabbit: adhesions and fertility.

Fertility and adhesions were examined in 41 rabbits in three treatment groups following the construction of microsurgical anastomoses with fibrin glue and by conventional suturing techniques. The three types of treatment were: isthmic anastomoses without resection, ampullary anastomoses, isthmic anastomoses following resection of oviduct segments. There were no significant differences between the two methods of performing the anastomoses in any of the three groups with respect to number of ovulations, number of implantations, nidation index, and pregnancy rate. The extent of the formation of adhesions was also no different between the two types of anastomosis construction. From the functional point of view, fibrin glueing of the tubes can be considered as good as microsurgical suturing. Another study is planned to examine whether this is also true from the morphological viewpoint. It must be remarked that fibrin glueing does not appear to be suitable for anastomoses in which a lumen-adjusting technique is needed or for deep tubocornual or intramural anastomoses.

Anastomosis, Surgical↗
PubMed1994

Oocyte donation in humans: a model to study the effect of age on embryo implantation rate.

Although a number of different mechanisms have been suggested to account for the decline of fertility with age, the majority of studies agree that poor oocyte quality and reduced endometrial receptivity are the most important. In fact, the increased incidence of early pregnancy loss and chromosomal abnormalities of oocytes in older women, as well as the ability to reverse decreasing pregnancy rates by using oocyte donation, strongly support the evidence that oocyte ageing is the main factor responsible for decreasing fertility. Conversely, the lack of knowledge of the physiological variables that determine a successful nidation of a human embryo makes the analysis of uterine receptivity much more difficult. In order to evaluate the impact of the age of donors and recipients on pregnancy, implantation and abortion rates, we have retrospectively analysed 258 cycles from our programme of oocyte donation. Results were reviewed according to the following subclasses of age groups: < or = 30, 31-35 and 36-39 years for donors, and < or = 30, 31-35, 36-40, 41-45 and 46-53 years for recipients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1982

Is estrogen required for implantation in the ferret?

A series of experiments was designed to further test the hypothesis that ferret corpora lutea synthesize and secrete estrogen between Days 6 and 8 of pregnancy, and that this estrogen is required to initiate implantation of blastocysts on Day 12. Corpora lutea, removed on Day 8 of pregnancy contained significant quantities of testosterone. Incubation of aliquots of the same luteal tissue for 4 h significantly elevated estrogen levels above those of nonincubated controls. Peripheral plasma estrogen levels exhibited a slight increase on Day 8 over those observed on Day 6 of pregnancy (7.9 +/- 3.4 vs. 4.1 +/- 1.1 pg/ml). However, continuous release of estradiol from Days 6-8 from two different sizes of Silastic capsules failed to induce implantation in ovariectomized-progesterone treated ferrets, whereas this same treatment was compatible with nidation in intact ferrets. Administration of the aromatase inhibitor, androsta-1,4,6-triene-3,17-dione (ATD) on Days 5-8 of pregnancy prevented implantation of blastocysts on Day 13. Simultaneous administration of estradiol and ATD failed to reverse the inhibitory effect of ATD. Results of this study confirm that luteal tissue of ferrets possesses at least one aromatizable androgen which is converted to estrogen under physiological conditions. However the data do not support the hypothesis that estrogen is required for implantation in the ferret.

Androstatrienes↗
PubMed1994

Abortifacient effects in the pregnant hamster of an antibody to progesterone are reversed by exogenous prolactin.

A single i.p. injection of 10 nmol of a monoclonal antibody to progesterone (mAb-P4) on Day 4 of pregnancy (day of nidation) interrupts pregnancy by Day 8 (Day 1 = sperm-positive smear) in 75% of treated hamsters (n = 8). This correlates with structural and functional luteolysis, significantly (p < 0.05) reduced serum prolactin (PRL), and a nonsignificant trend for reduced FSH (which constitute the minimal luteotropic complex of the hamster), but LH is unchanged. Embryos implant and develop normally for a while, but by Day 8 the uterus is distended with the resorbing products of conception. The abortifacient effects of passive immunization against progesterone are reversed 100% by s.c. injection of 100 micrograms PRL daily on Days 4-7; deferring PRL treatment until Days 6-7 maintained pregnancy in 75% of the animals, still significantly different from the untreated mAb-P4 group. Injection of 50 micrograms PRL on Days 4-7 maintains pregnancy in 50% of the mAb-P4-treated hamsters (not significantly different), whereas 10 micrograms PRL on Days 4-7 is wholly ineffective. No dose of FSH (0.1-10.0 micrograms) or LH (0.4-2.0 micrograms) on Days 4-7 reversed the effects of mAb-P4; neither did 10 micrograms PRL plus 0.4 or 2 micrograms of FSH. The maintenance of pregnancy after 100 micrograms PRL on Days 4-7 is associated with normal serum levels of PRL, FSH, and LH and no change in the serum concentration of the mAb-P4 antibody.(ABSTRACT TRUNCATED AT 250 WORDS)

Abortifacient Agents↗
PubMed1998

Evidence that a novel type of progestational phase control occurs in the corn mouse, a South American murid rodent.

Most Muridae display a short luteal phase that becomes functional as a consequence of the prolactin release induced by the stimulation of copulation and/or lactation. The corn mouse also shows a short luteal phase, and we wanted to know whether copulation and/or lactation would release prolactin and maintain progesterone secretion in this species. Females in postpartum estrus were either allowed to copulate with an intact male or not, and either to lactate their young or not. Afterward, plasma progesterone was elevated over the baseline level only in females that had copulated and were bearing growing embryos (whether or not they were lactating), while prolactin was elevated only in lactating females. In another experiment, endometrial scratching induced decidualization both in females that had copulated with a vasectomized male and in those that had not copulated; sham operations had no effect in either case. Progesterone levels were elevated in decidualized animals as compared with their sham-operated controls. Results indicate that the initiation of the progestational phase in the corn mouse is not dependent on prolactin release. A short luteal phase during which nidation may occur has not yet been described in any other mammal.

Animals↗
PubMed1986

Value of routine dilation and curettage at the time of interval sterilization.

Four hundred thirty-four patients underwent tubal ligation at the Beth Israel Hospital during a 27-month period. In 272 cases (62.7%), a dilation and curettage was performed as a routine part of the tubal ligation procedure to ensure that luteal phase pregnancy, if present, would be interrupted. Pathology reports on the curettings from all diagnostic dilation and curettages were reviewed. Evidence of pregnancy was found in seven, but only two (0.8%) proved to be of recent nidation. This series demonstrates that routine dilation and curettage at the time of sterilization may not be cost effective or efficient. Hormonal pregnancy testing, combined with accurate menstrual history and timing the tubal sterilization to occur during the follicular phase, if possible, are proposed as alternatives to operative intervention.

Abortion, Induced↗
PubMed1985

Placental proteins in the diagnosis and evaluation of the "elusive" early pregnancy.

For many many years much time and effort has been invested to identify, purify, and quantify markers of significant reproductive events. The search for such markers has been recently intensified with the widespread acceptance of IVF and ET as a treatment regimen for the management of certain causes of infertility. Now it is possible to monitor ovarian folliculogenesis and time of ovulation, successful fertilization, and subsequent nidation and the ensuing pregnancy. Following successful fertilization and zygote development, EPF, a protein complex which suppresses in vitro lymphocyte rosette formation can be detected within 24 hours. Shortly after implantation hCG can be measured in the maternal circulation. The developing trophoblastic tissue continues to synthesize and secrete into the maternal circulation many varied proteins including SP1, PAPP-A, and PP5. To date hCG is the mainstay of rapid and early pregnancy diagnosis and is an accepted biochemical marker of successful implantation and trophoblastic activity. Combination of hCG and EPF measurement offers the clinician new insight into his infertile patient for now it is possible to monitor successful fertilization and implantation as separate independent events. Such diagnostic assays should also provide new insight into early embryo mortality rate at the pre- and postimplantation stage and hence indicate the selection pressures acting on an embryo. It is the application of these assays which has led to the definition of subclinical abortions and to the description of biochemical pregnancies. The value of these proteins for the management of compromised early pregnancies has to be more fully examined. Although the differentiation between a normal and abnormal pregnancy is more readily ascertained by serial sampling and analysis of the time taken for circulating levels to double (3). Preliminary data suggest the potential of EPF and PAPP-A measurement in such clinical conditions is enormous. Our studies suggest that PAPP-A, at present, is the only biochemical marker which can predict pregnancy abortion, even in the presence of normal ultrasound scans, many weeks prior to the event, thus implying a vital biological role for PAPP-A in normal pregnancy (52). Despite the need for more intensive evaluation of these early pregnancy indicators the search for that "demmed elusive" marker has more than "Those Frenchies" earnestly looking for him here and there.

Abortion, Threatened↗