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E Hughes

Publications and source records attributed to E Hughes.

At least 55 records · Page 3Linked to original sources
PubMed2000

Danazol for unexplained infertilty.

BACKGROUND: The androgen, Danazol, was developed in the 1970's as a treatment for endometriosis. Its use was soon advocated in women with unexplained infertility. Two randomized trials were subsequently conducted to assess the effectiveness of danazol in this population. OBJECTIVES: The objective of this review was to assess the effects of danazol on pregnancy rates in women with unexplained subfertility. SEARCH STRATEGY: The Cochrane Subfertility Review Group specialised register of controlled trials was searched. SELECTION CRITERIA: Randomised trials of danazol compared with placebo or no treatment in women with unexplained subfertility. DATA COLLECTION AND ANALYSIS: Data were extracted by two reviewers. MAIN RESULTS: Two trials involving 68 women were involved. There was no difference found in pregnancy rate between danazol and placebo (odds ratio 2.57, 95% confidence 0.53 to 12.46). REVIEWER'S CONCLUSIONS: There is not enough evidence to evaluate the effect of danazol on pregnancy rates in women with unexplained subfertility. The need to use contraception during danazol treatment, adverse effects and costs are additional considerations.

Danazol↗
PubMed2000

Ovulation induction with urinary follicle stimulating hormone versus human menopausal gonadotropin for clomiphene-resistant polycystic ovary syndrome.

BACKGROUND: The risks of multiple pregnancy and ovarian hyperstimulation syndrome (OHSS) are increased in women with clomiphene resistance WHO group 2 dysfunction undergoing ovulation induction as well as the risk of spontaneous abortion if conception takes place. Semi-purified preparations of FSH have been developed in an effort to reduce the impact of exogenous LH, relatively high levels of which are present in human menopausal gonadotropin (hMG). Ovulation induction in women with clomiphene resistant WHO group 2 dysfunction who often have clinical features of polycystic ovarian syndrome (PCOS), is a major challenge. The risks of multiple pregnancy and ovarian hyperstimulation syndrome (OHSS) are increased in this population. There also appears to be an increased risk of spontaneous abortion in those who conceive, perhaps associated with elevated LH levels. Semi-purified preparations of FSH have been developed in an effort to reduce the impact of exogenous LH, relatively high levels of which are present in human menopausal gonadotrophins. OBJECTIVES: To determine the effectiveness of daily FSH versus daily hMG in women with clomiphene-resistant polycystic ovary syndrome (PCOS), in terms of rates of pregnancy and moderate to severe ovarian hyperstimulation syndrome (OHSS). SEARCH STRATEGY: The Cochrane Subfertility Review Group specialised register of controlled trials was searched. SELECTION CRITERIA: All RCTs relevant to the clinical question were selected. DATA COLLECTION AND ANALYSIS: A diverse search strategy was employed, including hand-search of 43 core journals from 1966 to the present, bibliographies of relevant trials, MEDLINE database, abstracts from North American and European meetings and contact with authors of relevant papers. Relevant data were extracted independently by two reviewers using the standardized data extraction sheet. Validity was assessed in terms of method of randomisation, completeness of follow-up, presence or absence of crossover and co-intervention. DATA SYNTHESIS: 2x2 tables were generated for all relevant outcomes. Odds ratios were generated using the Peto modified Mantel-Haenszel technique. Statistical heterogeneity was assessed using x2. MAIN RESULTS: No significant benefit was demonstrated from semi-purified FSH versus hMG in terms of pregnancy rate: common odds ratio per patient 0.66 (95% CI 0.35-1.24) and per cycle 0.89 (95% CI 0.51-1.53). FSH appeared to be associated with a reduction in moderate to severe OHSS: common odds ratios 0.2 (95% CI 0.09-0.46). REVIEWER'S CONCLUSIONS: In women with PCOS, no significant difference could be demonstrated between FSH and hMG, in terms of pregnancy rate. However, given similar cost, potential advantages in terms of purity and a possible reduction in OHSS risk, highly purified or recombinant FSH are likely to be widely adopted in the future. Further research should consider live birth as a primary clinical outcome, given concerns over the association between high androgen and LH levels with spontaneous abortion risk.

Clomiphene↗
PubMed2000

Oil-soluble versus water-soluble media for assessing tubal patency with hysterosalpingography or laparoscopy in subfertile women.

BACKGROUND: There has been debate in the literature for more than 40 years as to whether flushing of the Fallopian tubes enhances fertility and whether this presumed therapeutic effect is greater with oil-soluble media than with water-soluble media. A meta-analysis of the therapeutic role of oil-soluble contrast media at hysterosalpingography was published in March 1994 (Watson 1994). This Cochrane Review is an expansion and update of that overview. OBJECTIVES: To evaluate the effect of flushing the Fallopian tubes with oil- or water-soluble contrast media on subsequent pregnancy rates in infertility patients. SEARCH STRATEGY: 1. For randomised controlled trials (RCTs): we searched the Cochrane Subfertility Review Group specialised register of controlled trials. 2. For non-randomised controlled studies: Medline and manual search of eight relevant journals. SELECTION CRITERIA: Six RCTs and six non-randomised controlled studies. In two studies tubal flushing was compared with no treatment-controls. Eleven studies, comprising a total of 2635 subjects, compared oil- with water-soluble media. DATA COLLECTION AND ANALYSIS: Independently by first 2 authors for: 1. Methodological trial characteristics 2. Characteristics of participants 3. OUTCOMES: the main studied outcome was pregnancy rate per patient MAIN RESULTS: In comparison with no treatment, a significant benefit on pregnancy rates was seen by flushing the tubes with oil-soluble media (OR 1.80, 95% CI 1.29-2.50) but not with water-soluble media (OR 0.87, 95% CI 0.50-1.52). In the direct comparison of oil- and water-soluble media the former lead to significantly higher pregnancy rates (OR 1.92, 95% CI 1.60-2.29). The treatment effect appeared similar in RCTs and non-RCTs. Subgroup analysis suggested the therapeutic benefit was greatest for patients suffering from unexplained infertility and least for those with tubal factor infertility. REVIEWER'S CONCLUSIONS: Flushing of the tubes with oil-soluble media increases subsequent pregnancy rates in infertility patients. The hypothesis that tubal "plugs" are a cause of proximal tubal occlusion and that oil-soluble media may flush them out, is supported by new techniques such as falloposcopy. Clinicians should consider flushing the tubes with OSCM before contemplating more invasive therapies.

Contrast Media↗
PubMed2000

Gonadotrophin-releasing hormone analogue as an adjunct to gonadotropin therapy for clomiphene-resistant polycystic ovarian syndrome.

BACKGROUND: Elevation of endogenous LH levels may result in premature luteinization. This may also be associated with the increased rate of spontaneous abortion. Gonadotropin releasing hormone analogue (GnRHa) used prior to human menopausal gonadotropin (hMG/FSH) administration may improve the outcome of ovulation induction. OBJECTIVES: To assess if GnRHa pre-treatment plus FSH/hMG increase the rate of clinical pregnancy and/or decrease the rate of spontaneous abortion in women with WHO group 2 ovulatory dysfunction, compared with hMG/FSH alone. SEARCH STRATEGY: The Cochrane Subfertility Review Group specialised register of controlled trials was searched. SELECTION CRITERIA: All relevant published and unpublished RCTs were selected. Three RCTs were identified comparing these two approaches. DATA COLLECTION AND ANALYSIS DATA EXTRACTION: A diverse search strategy was employed, including hand-search of 43 core journals from 1966 to the present, bibliographies of relevant trials, MEDLINE database, abstracts from North American and European meetings and contact with authors of relevant papers. Relevant data were extracted independently by two reviewers using the standardised data extraction sheet. Validity was assessed in terms of method of randomisation, completeness of follow-up, presence or absence of crossover and co-intervention. DATA SYNTHESIS: 2x2 tables were generated for all relevant outcomes. Odds ratios were generated using the Peto modified Mantel-Haenszel technique. Statistical heterogeneity was assessed using x2. MAIN RESULTS: Studies were clinically and statistically homogenous. Common odds ratios for pregnancy per treatment cycle and moderate to severe ovarian hyperstimulation syndrome (OHSS) were 1.50 (0.72-3.12) and 1.40 (0.5-3.92) respectively. REVIEWER'S CONCLUSIONS: These studies are too small to clearly demonstrate clinically significant differences in pregnancy rate between the two approaches. However, data from IVF studies suggest that there may be an increased risk of OHSS associated with GnRHa use. In the absence of evidence suggesting a benefit of GnRHa augmentation for PCOS, it should not be recommended as a standard treatment for this patient group. Further studies assessing live birth and OHSS rates are warranted.

Clomiphene↗
PubMed2000

Growth hormone for in vitro fertilization.

BACKGROUND: Ovulation induction protocols for in vitro fertilization (IVF) are constantly under review and revision in an attempt to decrease gonadotropin requirements while improving follicular recruitment and pregnancy rate. Most studies of the effect of Growth Hormone on ovulation induction have investigated normally ovulating infertile women. Attention has begun to turn to its effect on women who fail to produce an optimal number of follicles in response to ovulation induction. OBJECTIVES: To assess the effectiveness of growth hormone adjuvant therapy for women undergoing ovulation induction prior to IVF in two patient groups: a) those with no previous history of poor response and b) those with a history of poor response. SEARCH STRATEGY: This review has drawn on the search strategy developed for the Subfertility Group as a whole. Relevant trials were identified in the Group's Specialised Register of Controlled Trials. See Review Group details for more information. SELECTION CRITERIA: All RCTs were included if they addressed the research question posed and provided outcome data for intervention and control subjects. Outcomes of interest included pregnancy, oocyte/embryo number and peak estradiol level. DATA COLLECTION AND ANALYSIS DATA EXTRACTION: A diverse search strategy was employed, including hand-search of 43 core journals from 1966 to the present, bibliographies of relevant trials, MEDLINE database, abstracts from North American and European meetings and contact with authors of relevant papers. Relevant data were extracted independently by two reviewers using the standardized data extraction sheet. Validity was assessed in terms of method of randomization, completeness of follow-up, presence or absence of crossover and co-intervention. DATA SYNTHESIS: 2x2 tables were generated for all relevant outcomes. Odds ratios were generated using the Peto modified Mantel-Haenszel technique. Statistical heterogeneity was assessed using x2. MAIN RESULTS: In women with no previous history of poor stimulation, the common odds ratio for pregnancy per cycle was 0.97 (95% CI 0.34-2. 76) Total dose of gonadotropin and number of oocytes retrieved were similar between treated and placebo groups. In previous poor responders, the common odds ratio for pregnancy per cycle instituted was 2.55 (95% CI 0.64-10.12). Again, no statistically significant difference was noted in gonadotropin dosage or oocyte number obtained, when all studies were considered. REVIEWER'S CONCLUSIONS: Data from 6 small trials suggest that in women with no previous poor response, GH augmentation does not improve the rate of pregnancy. In poor responders, a trend towards improved outcome with GH treatment deserves further study.

Female↗
PubMed2000

Androgens versus placebo or no treatment for idiopathic oligo/asthenospermia.

BACKGROUND: Oligo-astheno-teratospermia (sperm of low concentration, reduced motility and increased abnormal morphology) of unknown cause is common and the need for treatment is felt by patients and doctors alike. As a result, a variety of empirical, non-specific treatments have been used in an attempt to improve semen characteristics and fertility. Androgens have been suggested as a treatment because its binding proteins maintain a maintain a high intratesticular level testosterone essential for spermatogenesis and because the epididymis and seminal vesicles affect the seminal constitution and sperm motility and are also androgen-dependent. However exogenous testosterone was found to exert negative feedback on the pituitary-gonadal axis and thereby to suppress FSH and LH secretion. Spermatogenesis was thus adversely affected. Nevertheless androgens are used for the treatment of male infertility either for a putative direct "stimulatory" or "rebound" therapy. The stimulatory androgens used are mesterolone and testosterone undecanoate which, it is postulated, in a form and dosage that does not influence pituitary gonadotrophin secretion, either have a direct stimulatory effect on spermatogenesis or influence sperm transport and maturation though an effect on the epididymis, ductus deferens and seminal vesicles. Other androgens have been used to produce a rebound effect. These androgens are administered to suppress gonadotrophin secretion and spermatogenesis. After androgen therapy is discontinued there is a surge of FSH and LH and spermatogenesis is recommenced. Because of their different proposed mechanisms of action, stimulatory and rebound androgen therapy are analysed separately in the comparisons. This review considers the available evidence of the effect of androgens for idiopathic oligo and/or asthenospermia. OBJECTIVES: The objective of this review was to assess the effect of androgen treatment of men among couples where failure to conceive has been attributed to idiopathic oligo- and/or asthenospermia. SEARCH STRATEGY: The Cochrane Subfertility Review Group specialised register of controlled trials was searched". SELECTION CRITERIA: Randomised trials of mesterolone or testosterone undecanoate versus placebo or no treatment (stimulatory therapy), or testosterone enanthate or testosterone undecanoate versus placebo or no treatment (rebound therapy) in couples where subfertility is attributed to male factor. DATA COLLECTION AND ANALYSIS: Eligibility and trial quality were assessed. MAIN RESULTS: Eleven trials involving 930 patients were included. For stimulatory therapy, androgens had little effect on endocrinal outcomes and sperm parameters. The rate of pregnancy after androgens with stimulatory effect compared to no treatment or placebo was also similar (odds ratio 1.10, 95% confidence interval 0.75 to 1.61). In rebound therapy, no difference was found in sperm parameters. The pregnancy rate after androgens with rebound effect also showed no difference compared to no treatment or placebo (odds ratio 1.60, 95% confidence interval 0.42 to 6.16). Adverse effects such as headaches and exanthema were reported. REVIEWER'S CONCLUSIONS: There is not enough evidence to evaluate the use of androgens for male subfertility. [This abstract has been prepared centrally.]

Androgens↗
PubMed2000

Clomiphene or tamoxifen for idiopathic oligo/asthenospermia.

BACKGROUND: Oligo-astheno-teratospermia (sperm of low concentration, reduced motility and increased abnormal morphology) of unknown cause is common and the need for treatment is felt by patients and doctors alike. As a result, a variety of empirical, non-specific treatments have been used in an attempt to improve semen characteristics and fertility. The administration of anti-oestrogens is a common treatment because anti oestrogens interfere with the normal negative feedback of sex steroids at hypothalamic and pituitary levels in order to increase endogenous gonadotropin-releasing hormone secretion from the hypothalamus and FSH and LH secretion directly from the pituitary. In turn, FSH and LH stimulate Leydig cells in the testes, and this has been claimed to lead to increased local testosterone production, thereby boosting spermatogenesis with a possible improvement in fertility. There may also be a direct effect of anti-oestrogens on testicular spermatogenesis or steroidogenesis. This review considers the available evidence of the effect of both Clomiphene citrate and tamoxifen, both of which have a predominant anti-oestrogenic effect, for idiopathic oligo and/or asthenospermia. OBJECTIVES: The objective was to assess the effects of treating subfertile men with anti-oestrogens (clomiphene or tamoxifen) on pregnancy rates among couples where subfertility has been attributed to idiopathic oligo- and/or asthenospermia. SEARCH STRATEGY: The Cochrane Subfertility Review Group specialised register of controlled trials was searched". SELECTION CRITERIA: Randomised trials of anti-oestrogen therapy for 3 months or more compared to placebo or no placebo for subfertile males among couples where subfertility is attributed to male factor. DATA COLLECTION AND ANALYSIS: Data were extracted independently by two reviewers. Any differences were resolved with a third reviewer. MAIN RESULTS: Ten studies involving 738 men were included. Five of the trials did not specify method of randomisation. Anti-oestrogens had a positive effect on endocrinal outcomes, such as serum testosterone levels. In trials with secure randomisation there was no difference in the pregnancy rate between the anti-oestrogen groups and the control groups (odds ratio 1.26, 95% confidence interval 0.99 to 1.56). The overall pregnancy rate for these five trials was 15.4% compared to the spontaneous rate of 12.5% in the control groups. These odds increased to 1.56 (95% confidence interval 0.99 to 2.19) when all 10 trials were included, but this result is likely to be artificially inflated. REVIEWER'S CONCLUSIONS: Anti-oestrogens appear to have a beneficial effect on endocrinal outcomes, but there is not enough evidence to evaluate the use of anti-oestrogens for increasing the fertility of males with idiopathic oligo-asthenospermia.

Clomiphene↗
PubMed2000

Bromocriptine for idiopathic oligo/asthenospermia.

BACKGROUND: Oligo-astheno-teratospermia (sperm of low concentration, reduced motility and increased abnormal morphology)of unknown cause is common and the need for treatment is felt by patients and doctors alike. As a result, a variety of empirical, non-specific treatments have been used in an attempt to improve semen characteristics and fertility. Whilst bromocriptine treatment for reducing prolactin levels in hyperprolactinaemic males (as in females), and, in the treatment of hypogonadotropic hypogonadism with hyperprolactinaemia, is beneficial, it has also been used for oligospermic men in the absence of any endocrinopathy. Prolactin may play a direct role in spermatogenesis and hormone production. It has also been claimed that in oligospermic men with normal gonadotrophins mean prolactin levels are higher and that hyperprolactinaemia is more common compared to fertile men. It has been proposed that the administration of bromocriptine under these circumstances might counteract a prolactin-induced block on the action of gonadotrophins on the testicles and, subsequently, that the reduction in prolactin levels might lead to an improvement in semen parameters and fertility. Although it is not licensed for use in male infertility, bromocriptine has been used for normogonadotrophic individuals with oligospermia and normal or sligthly elevated prolactin levels. This review considers the available evidence of the effect of bromocriptine therapy for normoprolactinaemic males with idiopathic oligo and/or asthenospermia. OBJECTIVES: The objective of this review was to assess the effects of bromocriptine on pregnancy rates among couples where subfertility has been attributed to idiopathic oligo- and/or asthenospermia. SEARCH STRATEGY: The Cochrane Subfertility Review Group specialised register of controlled trials was searched". SELECTION CRITERIA: Randomised trials of oral bromocriptine versus placebo or no treatment for couples with subfertility attributed to male factor. DATA COLLECTION AND ANALYSIS: Data were extracted by one reviewer and any disagreements were resolved by discussion with other reviewers. MAIN RESULTS: Four studies were included. The method of randomisation was not specified in any of the trials, which were all of crossover design. Compared with placebo, bromocriptine was associated with a significant reduction in serum prolactin levels (weighted mean difference -195.3 micro international units per litre, 95% confidence interval -276.5 to -114). No effects on sperm parameters were seen. There was also no effect on pregnancy rates observed between bromocriptine and placebo (0.70 odds ratio, 95% confidence interval 0.15 to 3.24). REVIEWER'S CONCLUSIONS: Bromocriptine appears to reduce prolactin levels in subfertile men with normal gonadotrophic function. There is not enough evidence to show that bromocriptine is helpful in improving fertility.

Bromocriptine↗
PubMed2000

Kinin-enhancing drugs for unexplained subfertility in men.

BACKGROUND: Oligo-astheno-teratospermia (sperm of low concentration, reduced motility and increased abnormal morphology) of unknown cause is common and the need for treatment is felt by patients and doctors alike. As a result, a variety of empirical, non-specific treatments have been used in an attempt to improve semen characteristics and fertility. One suggested treatment for idiopathic oligo- and/or asthenospermia is the administration of kallikrein (kallidinogenase), a kinin-releasing enzyme (or kininogenase). The kinin biological system is complex and involves kininogen (the substrate), kininogenases (the activating enzymes), kinins (the effectors) and kininases (the inactivating enzymes). All four components of the kinin system have been found in the genitalia and in semen. Kallikrein releases 2 major kinins, kallidin and bradykinin, from seminal plasma kininogens. Activated kinins in semen affect sperm motility and metabolism. In vitro addition of kallikrein to semen has been shown to have a positive effect on sperm motility, sperm velocity, cervical mucus penetration, penetration of zona-free hamster eggs and post-thaw survival and motility rate after semen cryopreservation. The latter observation, however, was not confirmed in a more recent comparison of motility stimulants for cryopreserved semen using computerised sperm motion analysis. In vitro treatment of semen with kallikrein has been employed in a clinical context during sperm preparation prior to insemination. Although the kinin system may also be involved in the regulation of spermatogenesis in vivo, a clear mechanism of action is missing. Multiple suggestions on how an increase in kinin levels in the genital tract influences spermatogenesis at the testicular levels have been made by various authors. OBJECTIVES: To determine whether treatment of the male with drugs enhancing kinin levles increases pregnancy rates among couples where failure to conceive has been attributed to idiopathic oligo- and/or asthenospermia. Effects on sperm parameters and sex hormones were studied as secondary outcomes. SEARCH STRATEGY: The Cochrane Subfertility Review Group specialised register of controlled trials was searched". SELECTION CRITERIA: SIxteen RCTs on the therapeutic use of androgens (clomiphene citrate or tamoxifen) in subfertile men were identified. Six trials were excluded. DATA COLLECTION AND ANALYSIS: Methodological characteristics of trials Baseline characteristics of the studied groups Outcomes: Pregnancy rates, semen parameters (sperm concentration, motility and morphology), endocrinology (serum FSH, testosterone and oestradiol)

Fertility Agents, Male↗
PubMed2000

Ovulation suppression for endometriosis.

BACKGROUND: Although the etiology of endometriosis is unknown, several theories exist, the most popular of which is retrograde menstruation. As endometriosis can only be diagnosed by laparoscopy, neither the incidence (annual occurrence) nor the prevalence (proportion of the population affected) of endometriosis is known. The association between endometriosis and infertility isn't clear in Stage I (minimal) and Stage II (mild) endometriosis. Endometriosis appears to be an estrogen dependent condition. At the time of menopause, most endometriosis becomes quiescent. This hormonal dependency prompted researchers to seek agents which would suppress ovarian activity. OBJECTIVES: To determine effectiveness of a) ovulation suppression with danazol, medroxy progesterone acetate, gestrinone, combined oral contraceptive pills and GnRH analogues versus placebo or no treatment and b) any of the above agents versus danazol, for the treatment of endometriosis explained infertility in terms of clinical pregnancy rate. SEARCH STRATEGY: The Cochrane Subfertility Review Group specialised register of controlled trials was searched. SELECTION CRITERIA: Four RCTs with five treatment arms compared an ovulation suppression agent with placebo or no treatment. Eight trials were identified comparing a suppressive agent with danazol. DATA COLLECTION AND ANALYSIS DATA EXTRACTION: A diverse search strategy was employed, including hand-search of 43 core journals from 1966 to the present, bibliographies of relevant trials, MEDLINE database, abstracts from North American and European meetings and contact with authors of relevant papers. Relevant data were extracted independently by two reviewers using the standardised data extraction sheet. Validity was assessed in terms of method of randomisation, completeness of follow-up, presence or absence of crossover and co-intervention. DATA SYNTHESIS: 2x2 tables were generated for all relevant outcomes. Odds ratios were generated using the Peto modified Mantel-Haenszel technique. Statistical heterogeneity was assessed using x2. MAIN RESULTS: The common odds ratio for pregnancy following ovulation suppression versus placebo or no treatment was 0.83 (95% CI 0.5-1.39). These data were statistically homogeneous although clinical heterogeneity was present. Their consistency in showing no treatment benefit suggests that this group of interventions is ineffective. Common odds ratio for pregnancy following all agents versus danazol was 1.20 (95% CI 0. 85-1.68). Again these data were homogeneous and suggest no significant treatment benefit in terms of pregnancy rate. REVIEWER'S CONCLUSIONS: Given the significant period of amenorrhea associated with ovulation suppression, the lack of treatment benefit demonstrated and the adverse effects commonly associated with these treatments, ovulation suppression cannot be recommended as a standard therapy for endometriosis-associated infertility.

Danazol↗
PubMed2000

Gonadotrophin therapy for ovulation induction in subfertility associated with polycystic ovary syndrome.

BACKGROUND: Approximately 15% of patients with PCOS remain anovulatory despite treatment with oral anti-oestrogen medications such as clomiphene citrate. In addition, about half of women with PCOS ovulating on anti-oestrogen treatment fail to conceive. Gonadotrophin stimulation is the next step in treatment for women who are "clomiphene resistant", however, results of gonadotrophin stimulation in women with PCOS are less successful. In PCOS associated with hypersecretion of LH, purified urinary follicle-stimulating hormone (u-FSH) preparations have theoretical advantages over the use of human menopausal gonadotrophin (hMG) preparations (containing both FSH and LH), but whether this claimed advantage extends into clinical practice remains uncertain. In addition, the use of gonadotrophin-releasing hormone analogues (GnRH-a) to produce pituitary desensitisation prior to ovulation induction in PCOS has been claimed to increase the success rates of treatment as well as reduce complications such as OHSS and multiple pregnancy. Gonadotrophin preparations have also been administered via different routes (intramuscular or subcutaneous), or using different stimulation regimens and protocols (step-up or standard) in an attempt to improve efficacy. OBJECTIVES: To determine the effectiveness of urinary-derived gonadotrophins as ovulation induction agents in patients with PCOS trying to conceive. In particular, to assess the effectiveness of (1) different gonadotrophin preparations, (2) the addition of a gonadotrophin-releasing hormone agonist (GnRH-a) to gonadotrophin stimulation and (3) different modalities of gonadotrophin administration. SEARCH STRATEGY: The search strategy to identify RCTs consisted of (1) the Group's Specialised Register of Controlled Trials using the search strategy developed for the Menstrual Disorders and Subfertility Group as a whole (see the Review Group details for more information), (2) additional specific electronic Medline searches and (3) bibliographies of identified studies and narrative reviews. SELECTION CRITERIA: RCTs in which urinary-derived gonadotrophins were used for ovulation induction in patients with primary or secondary subfertility attributable to PCOS. DATA COLLECTION AND ANALYSIS: Twenty three RCTs were identified, 9 of which were excluded from analysis. The data were extracted independently by 2 authors. The following criteria were assessed: (1) the methodological characteristics of the trials, (2) the baseline characteristics of the studied groups and (3) the outcomes of interest: pregnancy rate (per cycle), ovulation rate (per cycle), miscarriage rate (per pregnancy), multiple pregnancy rate (per pregnancy), overstimulation rate (per cycle) and ovarian hyperstimulation syndrome (OHSS) rate (per cycle). Where suitable, meta-analysis was performed using Peto's OR with 95% CI with the fixed effect Mantel-Haentszel equation. MAIN RESULTS: (1) A reduction in the incidence of OHSS with FSH compared to hMG in stimulation cycles without the concomitant use of a GnRH-a (OR 0.20; 95% CI 0.08-0.46) and (2) a higher overstimulation rate when a GnRH-a is added to gonadotrophins (OR 3.15; 95% CI 1.48-6.70). REVIEWER'S CONCLUSIONS: Although 14 RCTs were included in this review, few dealt with the same comparisons, all were small to moderate size and their methodological quality was generally poor. Any conclusions, therefore, remain tentative as they are based on a limited amount of data and will require further RCTs to substantiate them. In none of the comparisons was there a significant improvement in pregnancy rate but this may be due to the lack of power (i.e. insufficient patients randomised to demonstrate a significant difference between treatments). There was a trend towards better pregnancy rates with the addition of a GnRH-a to gonadotrophin stimulation and these interventions warrant further study. Despite theoretical advantages, urinary-derived FSH preparations did not improve pregnancy rates when compared to traditional and cheaper hMG preparations; their only demonstrable benefit was a reduced risk of OHSS in cycles when administered without the concomitant use of a GnRH-a. No conclusions can be drawn on miscarriage and multiple pregnancy rates due to insufficient reporting of these outcomes in the trials.

Female↗
PubMed2000

Dependence of plasma alpha-tocopherol flux on very low-density triglyceride clearance in humans.

To evaluate the effect of dietary fat-induced alterations in triglyceride (TG) metabolism on plasma and very low-density lipoprotein (VLDL)-alpha-tocopherol, nine healthy males (mean +/- SEM, age: 36 +/- 3 years, BMI: 24.7 +/- 1.1) consumed a 35%-fat diet (control) for one week followed by a 15% low-fat, high-carbohydrate diet for 5 weeks. After each dietary phase, the subjects ingested an evening meal along with a 50 mg capsule of (2)H(6)-RRR-alpha-tocopheryl acetate; blood samples were drawn over a 24 h period while the subjects remained fasted. Low-fat feeding increased fasting plasma TG concentrations by 53% (116 +/- 27 to 178 +/- 32, mg/dl, p < 0.0001) primarily by reducing VLDL-TG clearance. Total plasma alpha-tocopherol concentrations (labeled + unlabeled) were unchanged (25.8 +/- 2.3 vs. 26.4 +/- 3.0 nmol/ml plasma) and no differences between the diets were observed for plasma (2)H(6)-alpha-tocopherol concentration (4.8 +/- 0.6 nmol/ml, for both diets) or enrichments (18.1 +/- 1.8% average for both diets). However, low-fat feeding significantly increased the amount of alpha-tocopherol in the VLDL fraction (43%, p = 0.04) in concert with elevations in VLDL-apoB and TG. The alpha-tocopherol and TG content of VLDL varied in parallel in individual subjects and fractional replacement rates and clearance of alpha-tocopherol and TG in VLDL were closely correlated. Kinetic parameters were decreased by 32-39% from high-fat to low-fat. These data suggest that vitamin E bioavailability is similar between a 15 and 35% fat diet, with a redistribution of alpha-tocopherol in lipoproteins occurring during low-fat feeding (increased in the VLDL fraction, reduced in the other lipoproteins), and transfer of alpha-tocopherol from VLDL depends upon TG removal from the particle, consistent with previous observations in vitro and in animal studies.

Adult↗
PubMed2000

13C-14N REAPDOR and 13C-2D theta-REDOR NMR on a blend of tri-p-tolylamine and bisphenol-A-polycarbonate.

Solid-state NMR experiments are performed on amorphous blends of tri-p-tolylamine (TTA) and polycarbonate. Amines that are similar to TTA are blended with polycarbonates and used as photoconducting components in xerography. Because of its simple molecular structure, TTA is a charge-transporting molecule that is used as a model to understand charge transport in photoconducting materials. Charge transfer between amine molecules must depend on the separation and relative orientation between amine molecules. However, little information is known about the structural relationship between the amine molecules and the polymer host, presumably because of the difficulties associated with characterizing amorphous materials. We report the results of 13C-14N rotational-echo, adiabatic-passage, double-resonance (REAPDOR) and 13C-2D theta-rotational-echo, double-resonance (theta-REDOR) magic-angle spinning NMR experiments on a TTA/polycarbonate blend. The experiments provide information about the organization of TTA relative to polycarbonate.

Aniline Compounds↗
PubMed2000

Brain chirps: spectrographic signatures of epileptic seizures.

OBJECTIVE: A chirp is a brief signal within which the frequency content changes rapidly. Spectrographic chirps are found in signals produced from many biological and physical phenomena. In radar and sonar engineering, signals with chirps are used to localize direction and range to the signal source. Although characteristic frequency changes during epileptic seizures have long been observed, the correlation with chirps and chirp technology seems never to have been made. METHODS: We analyzed 19404 s (1870 s of which were from 43 seizures) of intracranially (subdural and depth electrode) recorded digital EEG from 6 patients for the presence of spectral chirps. Matched filters were constructed from methods in routine use in non-medical signal processing applications. RESULTS: We found that chirps are very sensitive detectors of seizures (83%), and highly specific as markers (no false positive detections). The feasibility of using spectral chirps as matched filters was demonstrated. CONCLUSIONS: Chirps are highly specific and sensitive spectrographic signatures of epileptic seizure activity. In addition, chirps may serve as templates for matched filter design to detect seizures, and as such, can demonstrate localization and propagation of seizures from an epileptic focus.

Brain↗
PubMed1999

Side-chain structures in the first turn of the alpha-helix.

The first three residues at the N terminus of the alpha-helix are called N1, N2 and N3. We surveyed 2102 alpha-helix N termini in 298 high-resolution, non-homologous protein crystal structures for N1, N2 and N3 amino acid and side-chain rotamer propensities and hydrogen-bonding patterns. We find strong structural preferences that are unique to these sites. The rotamer distributions as a function of amino acid identity and position in the helix are often explained in terms of hydrogen-bonding interactions to the free N1, N2 and N3 backbone NH groups. Notably, the "good N2" amino acid residues Gln, Glu, Asp, Asn, Ser, Thr and His preferentially form i, i or i,i+1 hydrogen bonds to the backbone, though this is hindered by good N-caps (Asp, Asn, Ser, Thr and Cys) that compete for these hydrogen bond donors. We find a number of specific side-chain to side-chain interactions between N1 and N2 or between the N-cap and N2 or N3, such as Arg(N-cap) to Asp(N2). The strong energetic and structural preferences found for N1, N2 and N3, which differ greatly from positions within helix interiors, suggest that these sites should be treated explicitly in any consideration of helical structure in peptides or proteins.

Amino Acids↗
PubMed1999

Comparison of the prognostic value of qualitative versus quantitative stress tomographic perfusion imaging.

This study compared qualitative assessment of exercise thallium imaging to quantitative assessment in predicting outcome in 713 patients with 78% prevalence of coronary artery disease by coronary angiography; during a mean follow-up of 52 months, there were 106 hard cardiac events (death or nonfatal myocardial infarction). The qualitative method provided important prognostic information; however, unlike the quantitative technique, less patients were assigned to either the low- or high-risk group and proportionally more patients into the intermediate-risk group, which may limit the clinical usefulness of the technique.

Coronary Angiography↗
PubMed1999

Fluorine-19 solid-state NMR magic-angle-turning experiments using multiple-pulse homonuclear decoupling

For compounds giving "crowded" 1-dimensional magic-angle-spinning spectra, information about the local atomic environment in the form of the chemical shift anisotropy (CSA) is sacrificed for high resolution of the less informative isotropic chemical shift. Magic-angle-turning (MAT) NMR pulse sequences preserve the CSA information by correlating it to the isotropic chemical shift in a 2-dimensional experiment. For low natural abundance nuclei such as 13C and 15N and under 1H heteronuclear dipolar decoupling conditions, the dominant NMR interaction is the chemical shift. For abundant nuclei such as 1H, 19F, and 31P, the homonuclear dipolar interaction becomes a significant contribution to the observed linewidth in both F1 and F2 dimensions. We incorporate MREV8 homonuclear multiple-pulse decoupling sequences into the MAT experiment to give a multiple-pulse MAT (MP-MAT) experiment in which the homonuclear dipolar interaction is suppressed while maintaining the chemical shift information. Extensive use of computer simulation using GAMMA has guided the pulse sequence development. In particular, we show how the MREV8 pulses can be incorporated into a quadrature-detected sequence such as MAT. The MP-MAT technique is demonstrated for a model two-site system containing a mixture of silver trifluoroacetate and calcium difluoride. The resolution in the isotropic evolution dimension is improved by faster sample spinning, shorter MREV8 cycle times in the evolution dimension, and modifications of the MAT component of the pulse sequence. Copyright 1999 Academic Press.

Journal Article↗