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D de Ziegler

Publications and source records attributed to D de Ziegler.

87 records · Page 5Linked to original sources
PubMed1987

Factors influencing maintenance of sperm motility during in vitro processing.

Addition of serum to culture medium during washing of sperm was shown to significantly improve sperm motility upon subsequent 24-hour incubation, distinct from the beneficial effects of adding serum after washing. Commercial sources of human and bovine albumen tested did not preserve motility as well as serum, but addition to serum showed that the lesser effect was probably due to toxic contaminants. One of the most commonly available disposable plastic syringes was found to be markedly toxic to sperm. The materials found to have sperm toxicity also manifested toxicity to mouse embryos. These findings show that a similar degree of caution is advisable in testing of materials contacting sperm in vitro to that which has become standard practice for culture of human embryos.

Blood↗
PubMed1984

Isolation of prolactin-producing cells from first and second trimester decidua.

Two cell types isolated and purified to homogeneity from human decidua obtained at 8-17 weeks of gestation were shown immunocytochemically to correspond to decidual and epithelial cells in the tissue of origin. The decidual cells reacted with antihuman PRL antiserum, and epithelial cells reacted with antiserum against keratin, an epithelial cell marker. Decidual and epithelial cells were cultured separately to determine their abilities to release PRL to the medium. Decidual cells released 140-410 ng PRL/mg protein in 24 h, whereas no PRL was detectable in cultures of isolated epithelial cells. These homogeneous preparations provide an excellent system with which to study the regulation of PRL production and other biochemical properties of decidual components.

Adult↗
PubMed1982

Asymmetric release of estrone and estradiol derived from labeled precursors in perfused human placentas.

Human placentas were perfused in vitro through fetal vessels of a single cotyledon with a solution of tritiated androstenedione (A) or tritiated testosterone in oxygenated Krebs-Ringer bicarbonate buffer containing glucose. The same buffer, without labeled steroids, was used to perfuse the maternal side of the placenta. Fractions of unrecycled "fetal" and "maternal" perfusates were collected to estimate the steady-state rates of output into each perfusate of labeled estrone (E1) and estradiol (E2), formed by aromatization of the perfused androgens. An unequal distribution of the two estrogens was observed, i.e., a significantly larger proportion of E2 than of E1 was released to the maternal perfusate. Addition of unlabeled A or ethinyl estradiol (10(-5)M) to the fetal perfusion buffer resulted in a redistribution of the E2 output toward the fetal perfusate. These in vitro results are similar to the findings of Walsh and McCarthy, who detected by tracer experiments an unequality in the in vivo fetomaternal distribution of the output of placentally produced E1 and E2 in rhesus monkeys. These results also support the possibility of the existence of saturable specific E2 carriers in the syncytiotrophoblast, postulated by the same authors to explain their findings. However, an extrasyncytial conversion of E2 to E1 could also account for the disproportion in the relative output of the estrogens toward mother and fetus. The perfusion system used in these studies may be useful for the elucidation of factors determining the relative rates of placental secretion of steroids toward mother and fetus.

Androstenedione↗
PubMed1982

Production of prolactin by cultures of cells from human decidua.

Human decidual tissue has been reported to secrete human PRL in vitro. Decidual scraped from fetal membranes delivered at term was treated with collagenase, and cultures of the dispersed cells were examined 7 days after plating. These cultures were fibroblastic in appearance and secreted insignificant amounts of PRL to the medium (less than 12 ng/ml). However, PRL-producing cells could be selected by taking advantage of the slowness of their attachment to the plastic dishes. Cultures of cells that did not attach during the first 48 h after cell dispersion produced, after attachment, about 100 micrograms PRL/mg DNA in 2 days. This rate is much higher than rates observed during batch incubations or superfusions of minced decidual preparations (approximately 0.2-0.3 micrograms PRL/mg DNA.day). PRL production rates declined after the seventh day of culture, probably as a consequence of overgrowth of cells that did not secrete PRL. Cultures enriched in PRL-secreting cells may be used to study the regulation of decidual production of PRL and other biochemical processes of the endometrium affected by decidualization.

Cells, Cultured↗
PubMed1976

Ovarian control of gonadotropin secretion during induced precocious sexual maturation in the rat.

In sexually immature female rats 'primed' with a unilateral basal hypothalamic lesion on day 23 of life, a gonadotropin surge was triggered by progesterone (P) on day 26. The influence of sequential ovariectomy (OVX) on this response was studied in an attempt to elucidate the mode of action of brain lesions inducing precocious sexual maturation in this species. OVX, carried out on days 23-26, abolished or greatly reduced the LH surge, but had little effect on basal LH concentrations. In contrast, basal FSH concentrations rose rapidly after OVX. In lesioned rats, the post-castration rise of FSH could be prevented by leaving the ovaries in place during the 1st 24 or 48 h. It is concluded that the lesion-induced maturation of the positive feedback mechanism underlying the pubertal preovulatory gonadotropin surge is mediated by the ovaries. In prepubertal rats at this age, tonic FSH release, but not tonic LH release, is under tight negative feedback control.

Animals↗
PubMedDate not supplied

Progesterone and progestins: applications in gynecology.

Achievements obtained in infertility treatments over the past two decades have sparked interest in optimizing progesterone administration. Although progesterone is absorbed orally when ingested in micronized form, bioavailability is poor because of extensive liver metabolism. This explains why full predecidual transformation of the endometrium cannot be achieved with oral progesterone and is therefore ineffective for luteal support in in vitro fertilization (IVF). Progesterone administered non-orally can duplicate the endometrial changes normally seen in the menstrual cycle in women whose ovaries are inactive. Similar results have been reported with intramuscular (i.m.) injections and vaginal administration, although tissue levels are higher in the latter case. The recent development of a controlled and sustained release vaginal progesterone gel, Crinone(R) 8%, has made the vaginal route clinically practical by limiting the number of necessary applications to 1 per day. This regimen has been found at least as effective as intramuscular (i.m.) injections in women whose ovaries are inactive (donor egg IVF) and for luteal support in regular IVF. Hence, painful daily i.m. injections of progesterone in oil become unnecessary. The possibility of reducing the number of daily applications of vaginal progesterone to 1 per day, made possible by the sustained release gel Crinone, has opened new possibilities for long-term treatments, as in hormone replacement therapy (HRT). The low incidence of systemic side effects with use of the vaginal progesterone gel used for HRT in amenorrheic women, contrasts with findings related to use of synthetic progestins. Preliminary data suggest that vaginal progesterone can be instrumental in enhancing the notoriously poor long-term compliance of HRT.

Administration, Intravaginal↗
PubMedDate not supplied

Transvaginal progesterone: evidence for a new functional 'portal system' flowing from the vagina to the uterus.

The results of many recent experimental and clinical studies support the hypothesis that progesterone administered vaginally is distributed selectively to the uterus where tissue concentrations and effects exceed expectations. This phenomenon has multiple clinical implications in several fields of gynaecological endocrinology, notably in assisted reproductive treatments and new forms of hormone replacement therapy. Yet, the actual mechanisms by which vaginal administration of progesterone can induce higher concentrations in the uterus, despite low concentrations in the systemic circulation, remain obscure and most puzzling to many gynaecologists. This review aims to muster ideas and propose different mechanisms to explain the observed phenomenon. In particular, we will summarize data that support the various putative modes of transport including, direct diffusion through tissue, intracervical aspiration, absorption into the venous or lymphatic circulatory systems and countercurrent vascular exchange with diffusion from utero-vaginal veins/lymph vessels to arteries. All these mechanisms may concur to various extents to the uterine specificity of vaginal progesterone.

Administration, Intravaginal↗
PubMedDate not supplied

[Study of sperm-cervical mucus interaction in controlled cycles: feasibility of a new approach].

We report a prospective trial of in vitro sperm-mucus penetration test performed in hormonally controlled environment. To enhance the quality of the cervical mucus (CM), prevent spontaneous ovulation and to eliminate the possibility that results may be biased solely because of CM inadequacy, we conceived a 28-day physiological hormonal replacement regimen. For this women received oral estradiol valerate (E2-V) (4 mg/day) from cycle 1 to 28. CM was collected on days 13 (n = 17), 14 (n = 38) or 15 (n = 16), according to patients' individual preferences. The in vitro sperm-mucus penetration test was performed approximately 30 minutes later. On the same day, measurements of P and E2 levels were done to eliminate the possibility of spontaneous ovulation. Plasma E2 on the day of testing were 220 +/- 100 pg/ml (mean +/- SD). In all patients, except 4, P levels were low (< 1 ng/ml) on the day of the test. Our results indicate that a hormonal preparation with E2/P can be clinically useful for preventing spontaneous ovulation and reliably assuring CM quality when sperm/mucus penetration tests are performed.

Administration, Oral↗
PubMedDate not supplied

[Uterine contractions at the time of embryo transfer: a hindrance to implantation?].

OBJECTIVES: To investigate the hormonal control and the possible consequences of uterine contractions (UC) on IVF-ET outcome. MATERIALS AND METHODS: We studied prospectively 220 controlled ovarian hyperstimulation (COH) cycles for IVF-ET. Just before ET, women underwent 5-minute digital recordings of the uterus using US image analysis software for UC assessment. Plasma progesterone (P) and estradiol were measured. Four groups were defined according to UC frequency: < or = 3.0 (n = 53), 3.1 to 4.0 (n = 50), 4.1 to 5.0 (n = 43), and > 5.0 (n = 74) UC/minute, respectively. RESULTS: Patients, COH and embryology characteristics were comparable in all groups. Notwithstanding estradiol levels were not associated with UC characteristics, plasma P and UC frequency were negatively correlated (r = -0.34, P < 0.001). A stepwise decrease in clinical and ongoing pregnancy as well as implantation rates occurred from the lowest to the highest UC frequency groups (53%, 36%, 21%; 46%, 32%, 20%; 23%, 19%, 10%; and 14%, 11%, 4%; P < 0.001). Direction of UC did not affect ET outcome. CONCLUSIONS: The negative correlation between UC frequency and P levels supports the utero-relaxing properties of P. High frequency UC on the day of ET hinder IVF-ET outcome, possibly by expelling embryos out of the uterine cavity.

Adult↗