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Biomedical subjects

R M Winston

Publications and source records attributed to R M Winston.

At least 127 records · Page 7Linked to original sources
PubMed1988

Mechanism and management of ovulatory failure in women with polycystic ovary syndrome.

Polycystic ovary syndrome is the most important cause of chronic anovulation. In women who fail to respond to clomiphene, low-dose FSH given in a step-wise fashion can induce normal follicular growth and ovulation. The failure of the action of endogenous FSH in these women may be related to reduced biological activity of circulating FSH, but may also involve inhibition of its action at follicular level by polypeptide growth factors such as EGF.

Androgens↗
PubMed1987

Gonadotrophic control of human granulosa cell glycolysis.

Follicular fluid lactate levels were measured in women undergoing infertility surgery during the follicular phase or oocyte recovery for in-vitro fertilization (IVF). In the largest ovulatory follicle lactate levels were low in the mid-follicular phase (group 1), 1.6-fold higher just prior to the onset of the luteinizing hormone (LH) surge (group 2) and a further 2.5-fold higher after the onset of the LH surge (group 3). In IVF patients mean lactate levels in all aspirated follicles were similar to those in group 3 subjects, but the levels within each patient were variable and were positively correlated with follicular volume. Basal granulosa cell lactate accumulation in vitro was 3-fold higher in group 3 compared with group 2 subjects, but stimulation by FSH or HCG was higher in group 2 (2- to 3-fold) compared with group 3 (1.4- to 2-fold). These results demonstrate that human follicular fluid lactate levels increase as a function of the maturity and size of the developing follicle. Granulosa cell lactate accumulation in vitro is under gonadotrophic control, which suggests that the effects observed in vivo reflect changes in granulosa cell glycolysis in response to gonadotrophic stimulation. Our findings support the concept that low molecular weight energy metabolites transduce gonadotrophin signals that regulate oocyte maturation.

Adult↗
PubMed1987

Morphology of human and experimental hydrosalpinges: a comparative study.

Infection, and possibly raised intra-luminal pressure, may be responsible for the morphological changes and associated infertility that occur with hydrosalpinx formation. Biopsies from human hydrosalpinges were studied by light microscopy and scanning and transmission electron microscopy. Loss of mucosal folds, atrophied epithelium and varying degrees of deciliation were the main features found. Mechanical hydrosalpinges were produced in rabbits by double clip application (duration of clip application varied from 8 to 52 weeks). Morphological study of animal hydrosalpinges showed partial or complete loss of mucosal folds, atrophied epithelium and varying degrees of deciliation. The severity of morphological changes was related to duration of clip application. It is concluded that raised intra-luminal pressure plays a role in the morphological changes seen in human hydrosalpinges and infertility in women after anatomically successful salpingostomy. The rabbit would appear to provide a suitable model for the study of human hydrosalpinges. The significance of these findings is discussed in relation to the clinical management of hydrosalpinges.

Animals↗
PubMed1987

Spontaneous contractile pattern of isolated circular and longitudinal muscle layers from the ampullae of normal and damaged fallopian tubes.

Ampullary biopsies were obtained from twenty-three normal fertile women and from eleven women with hydrosalpinges. The contractile activity of 4-mm muscle strips was studied isometrically in organ bath. Both normal circular and longitudinal muscle strips contracted with similar frequency, duration and amplitude. Circular and longitudinal muscle strips from hydrosalpinges contracted with a lower frequency and a longer duration and the amplitude of contractions was higher than normal. The difference in frequency and duration was statistically significant. The possible explanations for these differences in rhythmicity between normal and diseased fallopian tubes are presented and the prognostic relevance discussed.

Adult↗
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↗
PubMed1986

The effect of treatment on experimentally produced endometrial peritoneal implants.

Endometriosis was induced surgically by implanting pieces of endometrium in the uterine mesenteries of 50 rats. Their fertility was then assessed after various treatments. Ten rats with endometriosis were treated with microsurgical excision of implants, 10 with high-frequency diathermy, 10 with danazol, and 10 with intraperitoneal indomethacin. Ten more rats had implants that were left untreated. The results were compared with those of ten rats that had sham surgery with implantation of fat in the uterine mesenteries. Reproductive performance was better in control animals with sham surgery than in animals with endometrial implants. Maximum restoration of fertility was achieved with indomethacin. Microsurgery and danazol therapy both were effective in preventing residual endometriosis, but the animals tended to be less fertile after treatment. Adhesions were most pronounced after diathermy and least pronounced after microsurgery or indomethacin therapy. In rats treated with indomethacin, persistent endometriotic cysts were invariably smaller near the site of intraperitoneal injection: this suggests a local antiprostaglandin effect.

Animals↗
PubMed1985

Fertilization in vitro of cumulus-enclosed mouse oocytes: effect of timing of the ovulatory HCG injection.

Human chorionic gonadotropin (HCG) may be injected to time ovulation and plan oocyte retrieval for clinical in vitro fertilization (IVF). Neither clinical nor experimental data on effects of subtle alterations in timing of the HCG injection on oocyte fertilizability in vitro were available. We induced follicular development in immature hybrid mice with an injection (4 IU) of pregnant mare serum gonadotropin (PMSG). In the first series of experiments, HCG was given 42, 46 or 50 hours later. We collected cumulus-enclosed, oviducal oocytes for IVF using capacitated mouse sperm 13 hours after the last HCG injection. The fertilization incidence (mean, three experiments) fell as the PMSG-HCG interval was reduced (50 hours, 64%; 46 hours, 40%; 42 hours 24%), but this could be explained by a corresponding increase in spontaneous oocyte activation caused by prolonging the HCG-oocyte collection interval. In the second series of experiments, the latter was fixed at 13 hours; the PMSG interval was altered by staggering the initial PMSG injection. No spontaneous activation occurred, but oocytes collected after "early" HCG injection still showed significantly lower fertilization incidences (42 hours, 36%; 46 hours, 46%) compared with the 50-hour injection (66%). The possible clinical implication of this finding is discussed.

Animals↗
PubMed1985

Superovulation strategy before in vitro fertilization.

This chapter reviews current understanding of the control of spontaneous preovulatory follicular development in the natural ovarian cycle as a basis for the design and use of superovulation strategy before clinical IVF. The principles, limitations and practical aims of therapy using clomiphene citrate and HMG to stimulate multiple follicular development are outlined together with details of methods in current use to monitor ovarian response to these drugs and to time ovulation induction and egg collection with HCG. Examples of successful IVF treatment cycles are given. It is stressed that properly controlled clinical trials to judge the relative merits of the various superovulation methods in current use for IVF have not been undertaken. Possible new approaches to ovarian stimulation before IVF include the use of 'pure' FSH, LHRH and pulsatile gonadotrophin administration.

Chorionic Gonadotropin↗
PubMed1985

Transperitoneal migration and ovum capture in rabbits.

It is not fully understood how eggs are captured by the fallopian tube. The close proximity of tube and ovary, and the movements of the fimbria across the ovarian surface during ovulation, are believed to contribute to ovum pickup. We studied the efficiency of ovum capture when contact between fimbria and ovary is prevented and the extent to which ovum transmigration may contribute to fertility. Unilateral right oophorectomy was performed in 55 rabbits, which were divided into three groups: in Group A, the contralateral oviduct was left intact; in Group B, the ampulla of the contralateral oviduct was occluded; in Group C, contralateral total salpingectomy was performed. None of the rabbits in Group A conceived on the oophorectomized side. Seven of 19 animals became pregnant in Group B and 15 of 18 conceived in Group C. The results indicate that direct fimbrial-ovarian contact is not essential for ovum capture, and that ovum transmigration could contribute to fertility.

Animals↗
PubMed1984

Technique and results of ovarian microsurgery in preparation for in vitro fertilization.

A microsurgical technique was used to free the ovaries in women with severe adnexal adhesions, specifically to facilitate subsequent egg retrieval for in vitro fertilization. The surgical technique is described in detail. Eighteen of these patients had a single attempt at laparoscopic collection of oocytes. From 15 women in whom ovariolysis had been successful, 27 eggs were obtained (mean 1.8 eggs per patient). Three conceptions occurred following embryo transfer and one other patient conceived spontaneously. These results suggest that ovariolysis before extra-corporeal fertilization is worthwhile in selected cases.

Adult↗
PubMed1984

Granulosa cell steroidogenesis before in vitro fertilization.

Endocrine and gametogenic functions of the ovulatory follicle may be linked. To verify this, we studied granulosa cell steroidogenesis in relation to oocyte fertilization and preimplantation embryo development in vitro. Multiple follicles were stimulated in in vitro fertilization patients with clomiphene citrate and ovulation was induced with human chorionic gonadotropin (hCG). Oocytes were fertilized with husband's sperm and normal embryos were replaced 48 h later. Granulosa cells were separated from follicular fluid from 64 follicles and incubated for 3 h with and without aromatase substrate (1 microM testosterone). Progesterone and estradiol levels were measured in follicular fluid and incubation medium. Follicular fluid steroid levels and granulosa cell steroidogenesis showed no significant differences for oocytes which cleaved normally and those which did not. Granulosa cell aromatase activity was high in all follicles, suggesting that the low periovulatory follicular fluid estradiol level is not explained by a fall in granulosa cell aromatase after hCG. High granulosa cell progesterone production and follicular fluid progesterone were consistent with advanced granulosa cell luteinization. Oocytes undergoing polyspermic activation were from larger follicles with elevated follicular fluid progesterone levels, suggesting that follicular size and follicular fluid progesterone are correlated with "over-ripeness" and polyspermy. No simple relationship exists between oocyte function and the present indices of granulosa cell steroid metabolism.

Adult↗
PubMed1984

Fulguration versus resection of experimental endometrial peritoneal implants in the rat.

Endometriosis was induced in 20 rats. Treatment by diathermy was compared to treatment by microsurgical resection of endometrial implants. No significant differences were found between the 2 groups regarding ovulation, nidation index or pregnancy rates but significant difference in the extent of adhesion formation after surgery was evident. There were fewer adhesions in the microsurgical group. As the adhesions here were periuterine (and not peritubal as in the human) this could explain the lack of impact on the actual fertility of these rats.

Animals↗
PubMed1984

Serum oestradiol and preovulatory follicular development before in-vitro fertilization.

Twenty-three in-vitro fertilization (IVF) treatment cycles (four unstimulated and 19 clomiphene-stimulated) were assessed retrospectively to discern relationships among serum oestradiol (OE2) titre on the day that human chorionic gonadotrophin (hCG) was given and the number and size of ovulatory follicles available for aspiration of oocytes during laparoscopy 32-38 h after hCG injection. Since 12 of the cycles succeeded to the stage of embryo replacement and two normal term pregnancies resulted, the series as a whole offers a useful referent data base. When only one ovulatory follicle developed (n = 8) the average volume of aspirated follicular fluid was approximately 6 ml, equivalent to a follicular diameter between 22 and 23 mm. When multiple follicles developed (mean 2.7/patient, n = 15), average fluid volume/follicle was not significantly different, averaging approximately 5.5 ml. Serum OE2 titre on the morning before hCG was injected ranged between 0.9 and 5.5 nmol/l and corresponded to the number of follicles aspirated at laparoscopy. There was a highly significant linear correlation (r = 0.85, P less than 0.001) between this OE2 value (X nmol/l) and total aspirated fluid volume (Y ml) where Y = 2.07 + 3.65 X. Thus taking 6 ml as the 'typical' fluid volume, the calibration line and its 95% confidence limits could be used to establish provisional 'ideal' pre-hCG serum OE2 titre ranges corresponding to the development of one, two or three mature ovulatory follicles. This information, combined with a knowledge of the number of presumptive preovulatory follicles present (assessed by ovarian ultrasound), can aid the timing of the hCG injection before IVF.

Adolescent↗
PubMed1983

Tubal mucosa and ectopic pregnancy.

Fallopian tubes containing a gestation are frequently normal on macroscopical and gross histological examination. Scanning electron microscopy and light microscopy studies of tubal biopsies taken from five groups of women showed marked differences in the ciliated surface which was measured planimetrically on photographs. The proportion of ciliated cells was significantly lower in biopsies taken from 25 women with tubal pregnancies compared with that in biopsies from seven women with intrauterine pregnancies at the same gestation. Marked deciliation was also seen in eight women biopsied during tubal surgery sometime subsequent to an ectopic pregnancy and in four women biopsied during tubal surgery who subsequently had a tubal pregnancy when compared with a group of women biopsied during tubal sterilization.

Cell Count↗
PubMed1983

The epithelium of human hydrosalpinges: a light optical and scanning electron microscopic study.

Multiple tubal biopsies from 21 patients with thin-walled dilated hydrosalpinges and from 12 patients with thick-walled fibrous hydrosalpinges were studied. All the biopsies were examined by light microscopy and scanning electron microscopy and the ciliated surface area at multiple locations measured by planimetry. These biopsies were compared with control biopsies taken from 13 normal women at varying stages of the menstrual cycle.

Adult↗