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J F Kerin

Publications and source records attributed to J F Kerin.

At least 37 records · Page 2Linked to original sources
PubMed1989

Regulation of cholesterol side-chain cleavage and 17 alpha-hydroxylase/lyase activities in proliferating human theca interna cells in long term monolayer culture.

In this report we describe the development and characterization of a long term culture system to study regulation of the expression of 17 alpha-hydroxylase, cholesterol side-chain cleavage, and 3 beta-hydroxysteroid dehydrogenase in human theca interna cells. Conditions have been established for the dispersal, growth, freezing, and storage of functional human theca interna cells isolated from preovulatory follicles of women undergoing laparoscopy for gamete intrafallopian tube transfer and in vitro fertilization procedures. Theca interna cells grown under these conditions have a doubling rate of 28-32 h and are morphologically distinct from human granulosa cells grown under the same conditions. Theca interna cells were grown, passed for successive passages, and transferred into serum-free medium containing forskolin, hCG, LH, or cAMP analogs. There was a time- and dose-dependent increase in 17 alpha-hydroxylase activity and progesterone synthesis from endogenous precursors. Added pregnenolone was converted to 17 alpha-hydroxypregnenolone, which was further converted primarily to dehydroepiandrosterone and, to a much lesser extent, androstenedione. Progesterone was converted to 17 alpha-hydroxyprogesterone and 16 alpha-hydroxyprogesterone. In studies using 17 alpha-hydroxyprogesterone as substrate, no metabolism to androstenedione or any other product was detectable. Similarly, 4-pregnen-20 alpha-ol-one (20 alpha-dihydroprogesterone) was not metabolized to any detectable products. Northern analysis performed on total RNA obtained from forskolin-stimulated theca interna cultures verified that the increase in 17 alpha-hydroxylase activity was associated with a corresponding increase in levels of mRNA specific for 17 alpha-hydroxylase cytochrome P-450. Message levels for cholesterol side-chain cleavage P-450 were similarly increased in cells treated with forskolin. No detectable mRNA encoding aromatase cytochrome P-450 was discerned. This procedure for the preparation and study of proliferating human theca internal cells provides an opportunity to study regulation of the expression of steroidogenic enzymes and other cellular processes unique to human ovarian cells.

Aldehyde-Lyases↗
PubMed1988

Levels of steroid and protein hormones in antral fluids of women treated with different combinations of gonadotropins, clomiphene citrate, and a gonadotropin-releasing hormone analog.

Levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, progesterone (P), and total protein in follicular fluids collected from 18 patients pretreated with a gonadotropin-releasing hormone analog (GnRHa), in association with human menopausal gonadotropin (hMG) and FSH, were compared with values for 69 patients treated with FSH, hMG, FSH/hMG, or clomiphene citrate (CC)/hMG in an in vitro fertilization (IVF) program. The authors have established a number of significant differences in chemical and physical properties of follicular fluids of patients treated by different regimen, and concur with earlier evidence that the volume of a follicle, and its P and total protein content, are related to the maturity of the oocyte nested within the follicle. Overall, however, differences in concentrations of gonadotropins in follicular fluids between groups were not consistent with differences in follicular fluid steroid levels, and levels of immunoactive gonadotropins in follicular fluids were not in accord with dosages of exogenous immunoactive gonadotropin administered during hyperstimulation. The most favorable outcomes of IVF (greater than 70% of oocytes fertilized) were established with oocytes collected from patients treated with FSH only or with CC/hMG, and patients treated with FSH only yielded the highest average number of oocytes which fertilized in vitro (6.2 per patient).

Body Fluids↗
PubMed1988

Interrelationships between plasma hormone levels and the content of total protein, gonadotropins and steroid hormones in antral fluids of women undergoing in vitro fertilization.

Follicle development was induced in 41 women with follicle-stimulating hormone (FSH) and human menopausal gonadotropin. Blood samples were drawn and follicular fluids (FF) were aspirated when two or more follicles attained diameters of 15 to 17 mm. Levels of estradiol (E2), progesterone (P), FSH, and luteinizing hormone (LH) were determined in samples by radioimmunoassay, and relationships between the measured parameters in antral fluids and in serum were examined by least-squares linear regression analysis. Levels of LH in serum correlated with LH and FSH levels in FF (P less than 0.005). Concentrations of FSH in serum were positively related to levels of LH, FSH, E2, and total protein in FF (P less than 0.005). E2 levels in serum were predictive of E2 levels in FF only, and levels of P in serum were directly correlated with P levels in FF (P less than 0.05). With respect to the peculiarly broad range of predictions that could be drawn from the FSH content of serum, peripheral FSH provided a better predictive index of the chemical composition of antral fluid than did the level of any other single hormone measured in serum.

Female↗
PubMed1988

Methods used to improve gamete efficiency.

Male factor infertility accounts for a significant percentage of problems in infertile couples. With clinical utilization of the technologies for selection of good-quality spermatozoa from the ejaculate, our ability to successfully treat the severely affected male factor couple has improved. However, it must be remembered that even with current technologies, fertilization success is reduced in these patients but remains above a 50% level. Other factors that can be used in the future to improve on these statistics are being investigated in regard to the in vitro environment for gametes, that is, the type of culture medium, the methods of coincubation of the sperm and egg, and other methods of enhancement of sperm fertilizing potential. However, methods of sperm preparation will achieve improvement in a percentage of these males treated, and can be used to improve fertilization and pregnancy success. It is important to understand the limitations of the zona-free hamster test, but it is also important to use that test as a screening method for sperm handling. By utilizing the SPA to select out the optimal method of sperm preparation, the fertilization and pregnancy outcome can be improved. Overall, the live-birth rate in male factor infertile couples is lower than non-male-factor couples treated by IVF and GIFT. Until more is known about basic spermatozoal function, and the ability to improve that function in affected males, the live-birth rate should not be expected to change substantially.

Cell Separation↗
PubMed1988

The effect of transferring pronuclear embryos on pregnancy outcome after in vitro fertilization.

In a prospective clinical trial the pregnancy rate in patients matched for infertility status, degree of hyperstimulation, and number of oocytes recovered was unaffected by whether embryos were transferred while still pronuclear (day 1) or after they had undergone cleavage (day 2). The pregnancy rates per transfer were 27% and 22%, respectively, for the two transfer times. Unlike results of a previous study, no difference was detected in the outcome of pregnancies from the two groups.

Cell Division↗
PubMed1986

Experience with the cryopreservation of human embryos using the mouse as a model to establish successful techniques.

Mouse embryos at the one-, two-, and eight-cell stages have been used to optimize the conditions for cryopreservation of human oocytes and embryos. For storage in glass vials using 1.5 M dimethyl sulfoxide (DMSO) as a cryoprotectant and slow cooling (approximately 0.3 degrees C/min), phosphate-buffered medium was superior to Hepes-buffered medium. Termination of slow cooling at -80 degrees C before transfer to liquid nitrogen with subsequent slow thawing (approximately 8 degrees C/min) resulted in more embryos surviving than when cooling terminated at -40 degrees C and rapid thawing (approximately 500 degrees C/min) was employed. Dilution of DMSO upon thawing with medium containing 0.5 M sucrose gave higher embryo survival rates than a stepwise (0.25 M decrements) dilution. Using these techniques, three pregnancies were established upon the transfer of 11 frozen-thawed embryos to seven patients. Rates of embryo survival using the simpler cryopreservation technique of ice-free vitrification in 0.25-ml straws have been disappointing.

Animals↗
PubMed1986

Pregnancy-related chemotactic activity of human follicular fluid.

We measured chemotactic activity in 238 follicular fluids (FF) aspirated from 45 women who had undergone ovarian stimulation with a combination of clomiphene citrate and human menopausal gonadotropin for oocyte retrieval, in vitro fertilization, and embryo transfer. Fifteen of the treatment cycles resulted in pregnancy. The mean chemotactic activity, measured as the distance in microns granulocytic leukocytes migrated through a 3.0-micron membrane, was significantly higher in FF from conceptual cycles, compared with nonconceptual cycles. Serum chemotactic activity was significantly lower in conceptual cycles, compared with nonconceptual cycles. A chemotactic gradient appears to exist between the peripheral circulation and the ovarian follicle. The gradient favors the follicle in conceptual cycles, as indicated by the chemotactic quotient (the ratio of chemotactic activity of FF to serum). In conceptual cycles the chemotactic quotient was 1.7 +/- 0.17, compared with 0.7 +/- 0.03 for nonconceptual cycles. The presence of leukocyte chemotactic factor in FF appears to discriminate prospectively with a 90% degree of confidence between conceptual and nonconceptual in vitro fertilization and embryo transfer cycles.

Androstenedione↗
PubMed1985

Improved pregnancy rate in human in vitro fertilization with the use of a medium based on the composition of human tubal fluid.

Significantly more mouse zygotes developed to blastocysts in culture in a medium formulated on the composition of human tubal fluid (HTF) than in modified Tyrode's medium (T6). In a randomized 2 X 2 factorial trial of human in vitro fertilization that compared the two media and culture under oil versus culture in loosely capped tubes, significantly more clinical pregnancies (30% of 60 transfers) were obtained with HTF medium than with T6 medium (11% of 53 transfers). Decreasing the K+ content of HTF medium to that present in T6 medium significantly decreased the number of mouse zygotes that developed in culture. Modifying Ca++ levels had no effect. It is therefore likely that the higher K+ content in HTF medium is primarily responsible for the superiority of HTF medium over T6 medium, but other differences in the composition of the two media could contribute to the results observed.

Animals↗
PubMed1985

The effect of porcine relaxin vaginally applied at human embryo transfer in an in vitro fertilization programme.

It has been suggested that the polypeptide hormone relaxin is an early pregnancy factor which facilitates implantation and pregnancy maintenance. To test this hypothesis a double blind randomized placebo controlled trial was conducted where 2 mg purified porcine relaxin or distilled water was given in a vaginal gel on the day of embryo transfer and again 3 days later in a human in vitro fertilization (IVF) programme. There were 96 patients in the randomized trial and 73 patients who were treated concurrently in the same IVF programme acted as a further control group. Of the 51 patients who received relaxin, 10 pregnancies were confirmed and 8 continued successfully. In the 45 patients treated with placebo 10 pregnancies were also confirmed and 6 continued successfully. Amongst the 73 patients concurrently treated outside the trial 14 achieved a pregnancy and 10 continued to term. Thus, porcine relaxin given in these circumstances in a human IVF programme did not appear to improve or interfere with the pregnancy rate. Possible factors that affected the implantation rates in this trial are discussed.

Animals↗
PubMed1985

Culture factors affecting the success rate of in vitro fertilization and embryo transfer.

The development of one-cell mouse zygotes to the blastocyst stage in vitro has been used as a quality control for the media and handling procedures employed for human in vitro fertilization and embryo transfer (IVF/ET). One-cell mouse zygotes were placed in culture in medium containing bovine serum albumin. Aliquots of the same batch of medium containing female patients' homologous serum were used for the fertilization and culture of human oocytes. The following procedures were associated with high rates of mouse embryo development and human pregnancies following IVF/ET: adequate gassing and equilibration of the medium, double-rinsing of pipets and catheters used to handle embryos, use of a HEPES-buffered medium for manipulating embryos in the absence of an atmosphere containing 5% CO2, control of excessive temperature in the vicinity of the embryos, and ET using medium containing 50% patient's serum. The institution of these procedures gave more consistent pregnancy rates. However, there was no obvious association between fertilization and cleavage of human oocytes and the quality of the medium ascertained by the mouse embryo development test. In a continuing trial, we are comparing two culture media (modified Tyrode's and a medium formulated on the composition of human fallopian tube fluid [HTF]) and two culture techniques (culture in medium under oil in petri dishes and in loosely capped tubes). Significantly more mouse zygotes developed in HTF medium compared to Tyrode's medium. In a randomized 2 X 2 factorial trial with human IVF/ET, the highest pregnancy rate occurred when fertilization and culture were carried out in HTF medium under oil, but numbers are not yet sufficient to show any statistical difference between treatments.

Animals↗
PubMed1985

Evidence for a hypothalamic site of action of clomiphene citrate in women.

To examine the site of action of clomiphene citrate (CC), LH and FSH pulsatile amplitude, frequency, and responsiveness to GnRH (10 micrograms, iv) were studied in 11 women during the early follicular phase of the menstrual cycle. Six women received CC (150 mg/day) on cycle days 2, 3, and 4, while 5 women received placebo tablets. Blood samples were drawn at 10-min intervals for 8 h before and after the treatment regimen on cycle days 2 and 5, respectively. All women treated with CC had multiple follicular development, as determined by ultrasound. Peripheral levels of estradiol did not change after CC treatment, while progesterone levels decreased slightly. Mean levels of LH increased from 7.5 +/- 0.9 (+/- SEM) to 10.7 +/- 1.4 mIU/ml (P less than 0.05), and FSH increased from 6.7 +/- 0.9 to 10.1 +/- 0.9 mIU/ml (P less than 0.01). After exposure to CC, the pulse frequency of LH during an 8-h period increased significantly (3.3 +/- 0.7 on day 2 vs. 6.8 +/- 0.8 on day 5; P less than 0.01), while the pulse frequency of FSH increased from 3.8 +/- 0.6 to 5 +/- 1.4, as determined by computer pulse analyses. The pulse amplitude of LH and FSH was not significantly altered. In the placebo-treated group, neither pulse amplitude nor pulse frequency changed significantly between cycle days 2 and 5. Pituitary sensitivity to exogenous GnRH did not change after CC treatment. Since the pulsatile frequency of LH is governed by hypothalamic influences, these findings provide compelling evidence for a hypothalamic site of action for CC, probably by inducing an increase in the frequency of GnRH secretion.

Adult↗
PubMed1984

Improved conception rate after intrauterine insemination of washed spermatozoa from men with poor quality semen.

The efficacy of high intrauterine insemination of a washed motile fraction of spermatozoa from men with poor quality semen on the day after the luteinising hormone (LH) surge was compared with that of natural intercourse based on symptothermal methods and a single act of intercourse timed on the day after the LH surge in the same 35 couples in a controlled and randomised trial of the three types of cycle. Each couple had been trying to conceive for at least 3 years, the woman being potentially fertile and the only detectable defect related to poor semen quality. After 39 intrauterine insemination cycles, 8 women conceived (all in their first insemination cycle); this procedure was significantly more successful than LH-timed intercourse (0/38; p less than 0.05) and natural intercourse timed by symptothermal methods (1/34; p = 0.022). The technique of intrauterine AIH, with a 'Tomcat' catheter, was simple, painless, and uncomplicated.

Clinical Trials as Topic↗
PubMed1984

In vitro fertilization and embryo transfer program, Department of Obstetrics and Gynecology, University of Adelaide at the Queen Elizabeth Hospital, Woodville, South Australia.

A review is presented summarizing the in vitro fertilization experience at the University of Adelaide, Australia. Initial attempts utilizing the normal cycle were unsuccessful in obtaining a pregnancy. Since 1982 the overall ongoing pregnancy rate has been 21% per embryo transfer, 16% per laparoscopy, and 12% per treatment cycle. A detailed description of presently utilized methodology is presented.

Adult↗
PubMed1984

Culture factors in relation to the success of human in vitro fertilization and embryo transfer.

The development of 1-cell mouse zygotes to the blastocyst stage in vitro has been used as a quality control for the media employed for human in vitro fertilization and embryo transfer (IVF-ET). The following procedures were associated with high rates of mouse embryo development and human pregnancies following IVF-ET: adequate gassing and equilibration of the medium, double rinsing of pipettes and catheters used to handle embryos, use of a HEPES-buffered medium for manipulating embryos in the absence of an atmosphere containing 5% CO2, control of excessive temperature in the vicinity of the embryos, and ET using medium containing 50% patient's serum. The institution of these procedures gave more consistent pregnancy rates. However, there was no obvious association between fertilization and cleavage of human oocytes and the quality of the medium ascertained by the mouse embryo development test.

Animals↗
PubMed1984

Endocrinology of ovarian stimulation for in vitro fertilization.

Understanding of the endocrinology of in vitro fertilization has advanced rapidly in the past 5 years. Despite a multitude of ovarian stimulation regimens a particular regimen has not demonstrated a marked superiority. In principle the achievement of high FSH levels during the early follicular phase to recruit a maximum number of follicles with a tolerable degree of asynchrony for final maturation is confined to a limited time span or 'FSH window' of about 3 to 4 days before negative E2 feedback induces below-threshold FSH levels, thereby condemning all subsequent follicles in that cycle to atresia. It appears that one can widen and/or amplify the 'FSH window' too far from gross hyperstimulation resulting in the recruitment of many follicles with an intolerable degree of asynchrony. This may lead to a defective endocrine environment for the oocytes contained within these follicles or an abnormal luteal environment and an increased frequency of fertilization, cleavage and implantation failure. Whichever regimen is used, the stimulation should ideally be sufficient to promote the development of at least 3 follicles beyond 18mm diameter at the time of OPU. This can be expected to result in at least 2 embryos to be available for transfer. Monitoring of follicular response by a combination of E2 and ultrasonic parameters is recommended so that the administration of HCG is given close to the anticipated endogenous rise of LH. This can be achieved by detecting a reduction in the rate of E2 rise (to plateau).(ABSTRACT TRUNCATED AT 250 WORDS)

Chorionic Gonadotropin↗
PubMed1983

Incidence of multiple pregnancy after in-vitro fertilisation and embryo transfer.

7 multiple pregnancies occurred in a series of 20 pregnancies after oocyte recovery for in-vitro fertilisation and embryo transfer. After ovarian stimulation with clomiphene alone or with human menopausal gonadotropin, 102 laparoscopies were carried out in 62 women and the ongoing pregnancy rate beyond the first trimester was 17/102 laparoscopies (17%), including 5 sets of twins. 1 triplet and 1 twin pregnancy showed evidence of regression of two sacs and one sac, and both are progressing as singleton pregnancies at 16 and 34 weeks, respectively. 3 abortions occurred at 7, 8, and 9 weeks--a spontaneous abortion rate of 15%. The pregnancy and multiple pregnancy rates after stimulation with clomiphene alone or with human menopausal gonadotropin were comparable, but oocyte pickup based on a knowledge of the duration of the endogenous rise in luteinising hormone, rather than 36 h after administration of human chorionic gonadotropin, increased the pregnancy rate. As the quality and number of embryos transferred to the uterus increased, the risk of multiple pregnancy also rose. Consideration should therefore be given to restricting the number of embryos transferred to limit multiple pregnancies to twins.

Adult↗