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Biomedical subjects

D Loutradis

Publications and source records attributed to D Loutradis.

At least 55 records · Page 3Linked to original sources
PubMed1996

The in vitro development of mouse embryos beyond the blastocyst stage into the hatching and outgrowth stage using different energy sources.

PURPOSE: The purpose of this study was to investigate the effect of male and female serum supplementation on the in vitro development of mouse embryos beyond the blastocyst stage until the outgrowth stage since the latter may be related to the nidation of the embryo. We also studied the effect of EGF addition on embryo culture and blastocyst outgrowth. METHODS AND RESULTS: The blastocyst and hatching rates of two-cell mouse embryos cultured in Ham's F-10 + BSA, Ham's F-10 + male serum, or Ham's F-10 + female serum were found to be comparable (P > 0.05). The outgrowth rate of hatched blastocysts was significantly increased, though, when they were transferred to 50% male serum compared to either 50% BSA or 50% female serum (P < 0.01 and P < 0.05, respectively). In the last experiment, either 100 or 150 ng/ml EGF was added to the culture medium from the two-cell stage till blastocyst development and the latter were cultured till outgrowth in 50% BSA, male serum, or female serum. For both concentrations of EGF, the outgrowth rate was significantly higher in male serum compared to the other conditions (P < 0.01 and P < 0.05, respectively). The outgrowth rate was also higher when EGF was used compared to plain medium before transferring the blastocysts to either male or female serum (P < 0.01 for both). CONCLUSIONS: We conclude that the development of embryos to the outgrowth stage is significantly enhanced by male serum. The addition of EGF from the two-cell stage also significantly improves the outgrowth success rate for both male and female serum conditions.

Animals↗
PubMed1996

Oocyte donation to women over 40 years of age: pregnancy complications.

Recently, oocyte donation to women of advanced age has led to a considerable number of conceptions, thus increasing the age limit for becoming pregnant. A main consideration encountered by physicians, though, is the potential medical and obstetric complications of a pregnancy at an advanced age. In this study, the obstetric complications, as well as the perinatal outcome, of pregnancies of aged recipients (above 40) are presented and compared to those of younger recipients. A significantly higher incidence of gestational diabetes (P < 0.001), an increased incidence of pre-eclampsia (at the 10% level of significance) and an increased risk for thrombophlebitis (again at the 10% level) was observed in the older patients, but a careful follow-up during their pregnancy led to a highly satisfactory obstetric and perinatal outcome. A rigorous precycle medical screening (especially for cardiovascular diseases and diabetes) and a careful follow-up during pregnancy is, therefore, imperative so that oocyte donation to older women is not withheld and continues to provide fertility possibilities to otherwise sterile patients.

Adult↗
PubMed1996

A flexible protocol for the induction of recipient endometrial cycles in an oocyte donation programme.

Synchronization of the availability of good quality oocytes from donors and adequate endometrial maturation of recipients are very important for the success of an oocyte donation programme. A flexible protocol for the endometrial preparation of recipients is important in timing embryo transfer between days 17 and 19 of the cycle ('window of receptivity'). The purpose of this study was to evaluate the effect of the length of oestradiol administration to recipients on pregnancy outcome. Oestrogen administration was 8 mg/day, but its length varied prospectively from 6 to 27 days, followed by the addition of progesterone (100 mg daily i.m.) for 2-4 days according to the availability of good quality oocytes. Pregnancy outcome was evaluated regardless of age, indication for oocyte donation or number of embryos transferred per patient. The pregnancy rate per cycle was comparable when oestradiol was administered from 6 to 11 days before progesterone addition, while it dropped significantly thereafter. The variation in progesterone administration did not affect pregnancy outcome. These findings provide us with a greater flexibility by allowing us to vary oestradiol administration to recipients from 6 to 11 days prior to progesterone, reducing considerably, therefore, the need to cancel embryo transfer because of oocyte unavailability. Thus we can arrange to transfer embryos between days 17 and 19 of the recipient's cycle so as to obtain the best possible clinical outcome.

Adult↗
PubMed1995

Uterine pinopodes as markers of the 'nidation window' in cycling women receiving exogenous oestradiol and progesterone.

In 14 cycling women participating in an in-vitro fertilization (IVF) donation programme, we examined the timing of the 'nidation window' using as a stage-specific 'marker' the presence of fully developed pinopodes on the apical surface of the luminal uterine epithelium. Each woman received exogenous oestradiol from the second day of their cycle and progesterone starting on day 8 or day 15 of the oestrogenic treatment. The women underwent two biopsies during the same artificial cycle, on either days 6 and 9 or days 8 and 10 of the progesterone treatment. All patients to whom oestradiol was administered for 7 days prior to progesterone administration (n = 9), and two of the five treated with oestradiol for 14 days prior to the addition of progesterone, showed uterine pinopodes in either one or both biopsies. When present on a given day, pinopodes were at the same stage, developing, fully developed or regressing, showing that their total lifespan did not exceed 48 h. Fully developed pinopodes existed for 1 day only which may correspond to the short period of optimal endometrial receptivity observed in animal models. The timing of the presence of fully developed pinopodes varied from patient to patient, but these individual differences were not correlated with progesterone and oestradiol plasma concentrations. The brief duration of the nidation window and the observed individual variations in its timing suggest that the detection of uterine pinopodes could be a valuable tool for the prediction, on an individual basis, of the optimal date for successful egg replacement in IVF patients.

Adult↗
PubMed1995

A preliminary study of the effect of growth hormone on mouse preimplantation embryo development in vitro.

The role of growth hormone (GH) in follicular development, ovulation and embryo development is currently under reconsideration. In this study, we have tried to investigate the effect of GH on preimplantation development of mouse embryos in vitro. Zygotes and two-cell mouse embryos were cultured without (control) or with GH. For zygotes, the addition of 0.2 micrograms/ml of GH resulted in 77 +/- 1% of blastocysts formed and 66 +/- 3% rate of hatching (control 64 +/- 4 and 31 +/- 3%, p < 0.05 and p < 0.01, respectively). For two-cell embryos, the addition of 0.2 micrograms/ml of GH resulted in 87 +/- 2% of blastocysts formed and 60 +/- 4% hatching rate (control 76 +/- 4 and 47 +/- 5%, p < 0.05 for both). This positive effect of GH addition implies that the latter can support mouse preimplantation development in vitro and it suggests, along with its local action on the ovary and its possible effects, via the insulin-like growth factor system, on the tubal and uterine epithelium, a continuous role of this hormone in reproductive physiology from follicular maturation to embryonic development and, possibly, implantation.

Animals↗
PubMed1994

The effect of compounds altering the cAMP level on reversing the 2-cell block induced by hypoxanthine in mouse embryos in vitro.

The possibility of reversing the hypoxanthine induced 2-cell block in mouse embryos when cultured in conditions supplemented with compounds that increase (FSH, hMG, IBMX, hCG) or inhibit (GnRH-analogue) cAMP was assessed. When embryos were cultured in Ham's F-10 without hypoxanthine supplemented with each of the above compounds, no inhibition of blastocyst development was observed. Embryos were then cultured in Ham's F-10 with hypoxanthine supplemented again with each compound. For the addition of GnRH-analogue or FSH, the rate of blastocyst formation was comparable with that of the control medium with hypoxanthine alone. Instead, the addition of IBMX or hMG reversed the induced block. There was no reversible effect for the addition of 2 micrograms/ml hCG while the latter was observed with higher doses. The results from GnRH-analogue and IBMX addition show that, contrary to what was found for oocytes, stimulation of cAMP reverses the hypoxanthine-induced block in mouse embryos. FSH and hCG also had effects opposite to those observed for oocytes. It is unknown why hMG (FSH + LH) reverses the block. A lower cAMP degradation rate resulting in a higher cAMP level is a possible explanation. Our results provide further evidence that cleavage arrest by hypoxanthine has a different mechanism than the hypoxanthine-induced arrest of meiosis.

1-Methyl-3-isobutylxanthine↗
PubMed1994

Hysterosalpingography and hysteroscopy in female infertility.

A total of 323 women of reproductive age (19-40 years) were submitted to a complete investigation of infertility routinely including hysterosalpingography and hysteroscopy. In 177 cases (54.7%) no pathological conditions were found by either of the applied methods, while in 65 cases (20.1%) similar abnormalities were observed by hysterosalpingography and hysteroscopy with a global correlation of 74.8%. Hysterosalpingography also presented false positive results in 11.7% and false negative ones in 13.3% of all the studied cases. In conclusion, the combined use of these techniques in infertility investigation gives complete and accurate information about the uterine cavity, despite the disadvantages of hysterosalpingography due to false positive and false negative results.

Adult↗
PubMed1993

Follicular fluid inhibin levels in relation to age in patients in an in vitro fertilization and embryo transfer programme.

Inhibin (INH), oestradiol (E2) and progesterone (P) were measured in the follicular fluid (FF) of 22 patients 28-38 years old (Group A) and 11 patients 43-47 years old (Group B) who had received gonadotrophin stimulation in an in vitro fertilization and embryo transfer (IVF-ET) programme. The results indicated that INH, E2 and P levels were significantly lower and the E2/P ratio was higher in FF of Group B patients (older women) compared to those of Group A. There were six single pregnancies among patients of Group A. No difference was observed in follicular fluid INH, E2 and P levels as well as in E2/P ratio between pregnant and non-pregnant patients of Group A (Group A1 and Group A2, respectively). A positive correlation was found between FF concentrations of E2 and P, E2 and INH and P and INH in the three Groups and a negative one between INH and the E2/P ratio in Group B. It seems likely that ovarian INH and E2 production are controlled by different mechanisms and that INH response to ovarian hyperstimulation is altered by advancing age.

Adult↗
PubMed1991

Combined GnRH-agonist and HMG therapy in patients with stimulation failure.

This study deals with the combined therapy of GnRH-agonist (GnRH-a) and HMG for stimulation in 15 patients who failed two prior in vitro fertilization attempts. Fifty-three patients who received HMG without GnRH-agonist suppression served as controls. Comparing the HMG group with GnRH-a/HMG cycles, the cancellation rate dropped from 35.5% to 13.2%. Oocyte recovery was similar in both groups, as were the fertilization rates, 88.4% in GnRH-a and 82% in HMG cycles, respectively. The number of embryos available for transfer was virtually identical in both groups (3.7 vs. 3.6). Embryo cleavage speed was higher in GnRH-a than in HMG regimens. The E2 rise was smooth in the GnRH-a group compared to the sharp rise observed in the HMG group. The pregnancy rate per transfer was 30.5% in the GnRH-a group versus 20.5% in the HMG group. GnRH-a seems to offer a clear improvement to a number of stimulation failures.

Adult↗
PubMed1991

Preovulatory effects of the progesterone antagonist mifepristone (RU486) in mice.

The progesterone antagonist mifepristone (RU486), was given in mice once on different days of pregnant mare's serum gonadotrophin-human chorionic gonadotrophin (PMSG-HCG) treatment and its action upon the induction of ovulation studied. RU486 administered on the day after PMSG significantly reduced the ovulation rate. Ovulation was completely inhibited when the progesterone antagonist was given simultaneously with HCG, but RU486 administered 4 h after HCG treatment remained ineffective. The development of two-cell zygotes harvested on day 2 post-coitum from mice treated with RU486 on the day after the PMSG treatment was followed in vitro and showed a significant decrease in the number of embryos developing to blastocysts. These results favour the involvement of progesterone in the ovulation process, indicating a direct effect of this hormone at the ovarian level via a progesterone receptor-mediated action.

Animals↗
PubMed1991

Outcome of ovarian response after suppression with a gonadotropin releasing hormone agonist in different chronological periods prior to gonadotropin stimulation for in vitro fertilization.

Gonadotropin-releasing hormone analogues (GnRH-a) are currently used in combination with gonadotropins in ovarian stimulation for in vitro fertilization programs (IVF). The present study aims at evaluating the treatment cycles for IVF for which human menopausal gonadotropin (HMG) was initiated only when pituitary desensitization was confirmed regardless of the time of GnRH-a administration. Two groups of patients were examined. Patients in group A (n = 46) were commenced with HMG treatment on day 15 when E2 level was less than 40 pg/ml. Group B patients (n = 27) comprised the cycle treatments in which E2 levels were greater than 40 pg/ml on day 15. In these cases HMG was first given when E2 levels declined to less than 40 pg/ml. The fertilization rate was similar in both A and B groups, 71.6 and 67.7% respectively. The pregnancy rate per transfer was 27.5 and 34.6% in group A and B respectively. Multiple pregnancies were found at 18.1% in group A versus 44.4% in group B. It is concluded that postponement of HMG administration in patients with high levels of E2 on day 15 after GnRH-a administration seems to offer an improvement in embryo cleavage speed, pregnancy rate and multiple pregnancies.

Adult↗
PubMed1990

Prostaglandins: PGF2 alpha, PGE2, 6-keto-PGF1 alpha and TXB2 serum levels in dysmenorrheic adolescents before, during and after treatment with oral contraceptives.

Ten adolescents with primary dysmenorrhea (PD) were treated with the oral contraceptive (OC) Lyndiol 2.5 mg (R) for one cycle. The levels of PGF2 alpha, PGE2 and the metabolites of PGI2 and TXA2: 6-keto-PGF1 alpha and TXB2 were tested by a radioimmunoassay method during the 1st and 23rd day of the pre-treatment cycle (PrTC), the 23rd day of treatment (TC) and the 1st day of the post-treatment cycle (PoTC). The ratios PGF2 alpha/PGE2 and TXB2/6-keto-PGF1 alpha were also tested and compared during the above-mentioned days. Analytical comparison was made, for each Prostaglandin (PG) separately, between the 1st day of the PrTC and PoTC as well as the 23rd day of the PrTC and TC, respectively. All PG levels during TC and PoTC were found significantly lower, compared to those of the PrTC respectively. With regard to the ratios mentioned above, no statistically significant differences were found on the same days and cycles as previously stated. The reduction of the PG levels in PD patients after treatment with oral contraceptives, together with an improvement of the clinical findings of the disease, support the theory that oral contraceptives can be used for the treatment of PD cases, especially for those adolescents who also desire a contraceptive method.

6-Ketoprostaglandin F1 alpha↗
PubMed1990

The validity of gynecological ultrasonography.

The present study was undertaken to examine the reliability of the sonographic diagnosis in 705 gynecological patients. The determination of the lesions was defined according to the operative diagnosis. The sensitivity, specificity and positive predictive value of the ultrasound technique were evaluated using the surgical findings as 'gold standard'. In 631 patients (89.5%) the ultrasound examination established a correct diagnosis. The sensitivity and specificity of the ultrasound examination varied between 75-95.3% and 93.3-100%, respectively. The positive predictive value was found between 89.7 and 100%, while the false sonographic results were 10.4%, which included those of ectopic pregnancies. It is thus concluded that ultrasonography as compared to the surgical findings has proved to be of great value in establishing a gynecological diagnosis.

Adnexal Diseases↗
PubMed1988

FSH-induced ovulation in intact and hypophysectomized mice.

A single, ovulatory dose of 25 micrograms of a highly purified preparation of ovine FSH caused ovulation in 89% of hypophysectomized and 91% of intact female mice primed 48 h earlier with PMSG; the number of oocytes recovered (29.4 +/- 4.7 and 22 +/- 2.7/mouse ovulating, respectively) compared favourably with the 20.0 +/- 2.9 oocytes per ovulating female recovered from animals that received PMSG + hCG. After oFSH injection, 82% of oocytes released were fertilized and developed to blastocysts. That the trace contamination (less than 0.2%) of the oFSH with oLH was not responsible for the ovulation was shown by the markedly reduced number of oocytes collected from ovulating females that were injected with equivalent low levels of hCG (0.001 micrograms) or oLH (1 microgram) (9.0 +/- 3.3 and 8.0 +/- 3.1, respectively). These results demonstrate that oFSH is as effective as LH in inducing ovulation of competent oocytes in the mouse.

Animals↗
PubMed1987

Hypoxanthine causes a 2-cell block in random-bred mouse embryos.

Ham's F-10, a chemically defined, complex culture medium, commonly used for in vitro fertilization of human as well as animal oocytes, blocked development at the 2-cell stage of greater than 92% of embryos from random-bred Swiss mice (CD-1), but did not block development of embryos from hybrid-inbred mice (BDF1). In contrast, BWW, a simple, modified Kreb's-Ringer bicarbonate medium, supported development to blastocysts of 85% and 100% of 2-cell embryos from CD1 and BDF1 females, respectively. As little as 15% (v/v) Ham's F-10 added to the BWW blocked the development of the random-bred embryos. Supplementing the BWW with Ham's F-10 components revealed that hypoxanthine (6-30 microM) was responsible for the developmental block to the random-bred embryos. The hypoxanthine block was partially (40%) reversed by adding the chelating agent, ethylenediaminetetraacetic acid. Breeding experiments showed that the hypoxanthine sensitivity of embryos from CD-1 mothers was not affected by the paternal genome.

Animals↗
PubMed1985

Treatment of anaerobic female genital tract infections with metronidazole.

Intravenous metronidazole was given to 12 patients with severe genital tract infections. Nine of them suffered from acute salpingitis or pelvic inflammatory disease and the remaining three from acute endomyometritis following cesarean section. Metronidazole was the only antimicrobial agent given to 4 patients. In the remaining eight, treatment had been started with other drugs such as gentamicin and/or penicillin, and metronidazole was added two to five days later. Blood cultures and cultures taken from the cervical os or pus of abscesses had previously shown either anaerobic or mixed pathogens. All patients recovered well. No severe side effects were observed during metronidazole therapy. To study the pharmacokinetics of metronidazole the drug was administered intravenously or orally. The levels of the drug in the menses and cervical mucus of 25 healthy women were tested using the agar diffusion method. The concentration of the medication in the menses and mucus was found to adequately inhibit in vitro the most commonly anaerobic pathogens found in female genital tract infections.

Bacteria, Anaerobic↗