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M Proctor

Publications and source records attributed to M Proctor.

At least 19 recordsLinked to original sources
PubMed2005

Cleavage stage versus blastocyst stage embryo transfer in assisted conception.

BACKGROUND: In the past decade, advances in the understanding of nutrient requirements of embryos, has led to the evolution of culture media designed to support extended culture of embryos in vitro from the standard procedure of 2 to 3 days (for early cleavage embryo transfer) to 5 to 6 days (blastocyst culture). The rationale for blastocyst culture is to improve the synchronicity of uterine and embryonic development and provide a mechanism for self-selection of viable embryos. Since the initial widespread introduction of blastocyst culture in 1998, there has been conflicting reports about the clinical benefits of this technique. OBJECTIVES: To determine if blastocyst stage embryo transfers (ETs) affects success rates compared with cleavage stage ETs and investigate what factors may influence this. SEARCH STRATEGY: We searched the Cochrane Menstrual Disorders and Subfertility Group Specialised Register of controlled trials. We also searched the Cochrane Controlled Trials Register (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and Bio extracts. Attempts were made to identify trials from the National Research Register, the Clinical Trials Register and the citation lists of review articles and included trials. The last search date was May 2005. The first or corresponding author of each included trial was contacted for additional information. SELECTION CRITERIA: Trials were included if they were randomised and compared the effectiveness of early cleavage versus blastocyst stage transfers. DATA COLLECTION AND ANALYSIS: Of the 45 trials that were identified, 16 trials met the inclusion criteria and were reviewed. Primary outcomes were rates of live birth, clinical pregnancy and multiple-pregnancy rates per couple. Secondary outcomes were rates of miscarriage, failure to transfer embryos, freezing, implantation and high order pregnancy and per cycle data. Quality assessment and data extraction were performed independently by two review authors. Meta-analysis was performed using odds ratios (OR) for dichotomous outcomes and weighted mean differences for binary outcomes with 95% confidence intervals (CI). MAIN RESULTS: There was no evidence of a difference in live-birth rate per couple between the two treatment groups (7 RCTs; OR 1.16, 95% CI 0.74 to 1.44 [Day 2/3 34.3% vs. Day 5/6 35.4%]); in the clinical pregnancy rate per couple (15 RCTs; OR 1.05, 95% CI 0.88 to 1.26 [Day 2/3 38.8% vs. 40.3%]) even for good prognosis patients (6 RCTs: OR 96% 1.06 CI 0.83 to 1.34). There was also no difference in multiple-pregnancy rate per couple (12 RCTs; OR 0.85, 95% CI 0.63 to 1.13) particularly in trials where equal numbers of embryos were transferred in both groups (6 RCTs: OR 0.91, 95% CI 0.63 to 1.32). There was no evidence of a difference in high order multiple-pregnancy rates per couple (5 RCTs; OR 0.44, 95% CI 0.15 to 1.33) or miscarriage rate per couple between the two groups (9 RCTs; OR 1.33, 95% CI 0.89 to 2.01). Rates of embryo freezing per couple was significantly higher in Day 2 to 3 transfers (9 RCTs; OR 0.45, 95% CI 0.36 to 0.57). Failure to transfer any embryos per couple was significantly higher in the Day 5 to 6 group (10 RCTs: OR 3.21, 95% CI 2.15 to 4.81[Day 2/3 3.5% vs D 5/6 10.1%]), but was not significantly different for good prognosis patients (7RCTs, OR 1.58 95% CI 0.65 to 3.82). AUTHORS' CONCLUSIONS: There is no evidence of a difference in live birth or pregnancy outcomes between Day 2 to 3 and Day 5 to 6 transfer of embryos. Blastocyst transfer was associated with an increase in failure to transfer any embryos in a cycle and a decrease in embryo freezing rates. In the absence of data on cumulative live birth rates resulting from fresh and thawed cycles, it is not possible to determine if this represents an advantage or disadvantage.

Blastocyst↗
PubMed2005

Recombinant versus urinary human chorionic gonadotrophin for ovulation induction in assisted conception.

BACKGROUND: For the last few decades urinary human chorionic gonadotrophin has been used to induce final follicular maturation and for triggering ovulation in assisted conception. Recombinant technology has allowed the production of two drugs that can be used for the same purpose: to mimic the endogenous luteinizing hormone (LH) surge. This would allow commercial production to be adjusted according to market requirements. In addition all urinary contaminants would also be removed. Hence, this would allow the safe subcutaneous administration of a compound with less batch-to-batch variation. However, prior to a change in practice, the effectiveness of the recombinant drugs should be known, compared to the currently used urinary human chorionic gonadotrophins. OBJECTIVES: To assess the safety and efficacy of subcutaneous rhCG and high dose rLH compared with intramuscular uhCG for inducing final oocyte maturation and triggering ovulation. SEARCH STRATEGY: We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (27 August 2003), the Cochrane Central Register of Controlled Trials (CENTRAL on The Cochrane Library, issue 4, 2003), MEDLINE (1966 to Feb 2004) and EMBASE (1980 to Feb 2004). Searches were not limited by language. The bibliographies of included, excluded trials and abstracts of major meetings were searched for additional trials. Authors and pharmaceutical companies were contacted for missing and unpublished data. SELECTION CRITERIA: Two reviewers independently scanned titles and abstracts, and selected those that appeared relevant for collection of the full paper. Only truly randomised controlled trials comparing rhCG or high dose r-LH with urinary hCG for triggering ovulation in assisted conception for treatment of infertility in normogonadotrophic women were included. DATA COLLECTION AND ANALYSIS: Assessment of inclusion/exclusion, quality assessment and data extraction were performed independently by at least two reviewers. Discrepancies were discussed in the presence of a third reviewer and a consensus reached. Quality assessment included method of randomisation, allocation concealment, blinding of participants and assessors, reporting of a power calculation, intention to treat analysis, and handling of dropouts. Data extraction included characteristics of participants, the intervention and control procedures, and outcomes. MAIN RESULTS: Seven RCTs were identified, four comparing rhCG and uhCG and three comparing rhLH and uhCG. There was no statistically significant difference between rhCG vs uhCG regarding the ongoing pregnancy/ live birth rate (OR 0.98, 95% CI 0.69 to 1.39), pregnancy rate, miscarriage or incidence of OHSS. There was no statistically significant difference between rhLH vs uhCG regarding the ongoing pregnancy/ live birth rate (OR 0.94, 95% CI 0.50 to 1.76), pregnancy rate, miscarriage or incidence of OHSS. The manufacturer of rhLH has decided not to further develop this product. rhCG was associated with a reduction in the incidence of local site reactions and other minor adverse effects (OR 0.47, 95% CI 0.32 to 0.70). AUTHORS' CONCLUSIONS: There is no evidence of difference in clinical outcomes between urinary and recombinant gonadotrophins for induction of final follicular maturation. Additional factors should be considered when choosing gonadotrophin type, including safety, cost and drug availability.

Chorionic Gonadotropin↗
PubMed2005

Oral anti-oestrogens and medical adjuncts for subfertility associated with anovulation.

BACKGROUND: Infertility due to anovulation is a common problem in women. The first line oral treatment is with anti-oestrogens, such as clomiphene citrate. Unfortunately there may be resistance and alternative and adjunctive treatments have been developed. These include tamoxifen, dexamethasone, bromocriptine and aromatase inhibitors (AIs). OBJECTIVES: To determine the relative effectiveness of anti-oestrogen agents, with or without medical adjuncts, in women with WHO group 2 anovulation. SEARCH STRATEGY: We searched the Cochrane Menstrual Disorders and Subfertility Group trial register (searched 5th July 2004), CENTRAL (The Cochrane Library Issue 2 2004), MEDLINE (1966 to June 2004) and EMBASE (1980 to June 2004) for identification of relevant randomised controlled trials (RCTs). Additionally the United Kingdom National Institute for Clinical Excellence (NICE) guidelines and the references of relevant reviews and RCTs were searched. SELECTION CRITERIA: RCTs that compare oral anti-oestrogen agents for ovulation induction (alone or in conjunction with medical adjuncts) in anovulatory subfertility, were considered for inclusion in the review. Metformin and other insulin sensitizing agents were not included. Hyperprolactinaemic infertility was not included. DATA COLLECTION AND ANALYSIS: Data extraction and quality assessment was done independently by two reviewers. The primary outcome was live birth, secondary outcomes were: pregnancy, ovulation, miscarriage, multiple pregnancy, overstimulation, ovarian hyperstimulation syndrome and patient reported adverse effects. MAIN RESULTS: Twelve RCTs were found and included in this review. No trials reported live birth as an outcome. Miscarriage and multiple pregnancy rates were poorly reported. Clomiphene was shown to be effective in increasing pregnancy rate when compared to placebo (fixed OR 5.8, 95% CI 1.6 to 21.5; NNT 5.9, 95% CI 3.6 to 16.7). No evidence of a difference in effect was found between clomiphene and tamoxifen (fixed OR 1.0, 95% CI 0.5 to 2.1). The use of clomiphene in combination with tamoxifen did not find any evidence of effect on pregnancy rate when compared to clomiphene alone (fixed OR 3.3, 95% CI 0.1 to 91.6). The comparison between two AIs (letrozole and anastrozole) did not find any evidence of a difference in effect on pregnancy rate (fixed OR 1.9, 95% CI 0.4 to 8.9). For the intervention of clomiphene plus ketoconazole vs clomiphene no evidence of a difference in effect for pregnancy rate was found (fixed OR 2.4, 95% CI 0.9 to 6.4). For clomiphene plus bromocriptine vs clomiphene no evidence of a difference in effect on pregnancy rate was found (fixed OR 1.0, 95% CI 0.3 to 3.0) rates. However, clomiphene plus dexamethasone treatment resulted in a significant improvement in the pregnancy rate (fixed OR 11.3, 95% CI 5.3 to 24.0; NNT 2.7, 95% CI 2.1 to 3.6) when compared to clomiphene alone as did clomiphene plus pretreatment with combined oral contraceptives (fixed OR 27.2, 95% CI 3.1 to 235.0; NNT 2.0, 95% CI 1.4 to 3.4). AUTHORS' CONCLUSIONS: This review shows evidence supporting the effectiveness of the current first line treatment, clomiphene citrate. No evidence of a difference in effect was found between clomiphene and tamoxifen. The use of dexamethasone as an adjunct to clomiphene therapy appears promising as do combined oral contraceptives. This review has highlighted a gap in the literature on effects of these drugs on outcomes such as miscarriage rate. Evidence in favour of these interventions is flawed. RCTs of adequate power and of high methodological quality are required for the older treatments such as clomiphene, alone and with medical adjuncts, and also for the newer drugs such as the AIs.

Anovulation↗
PubMed2004

The merits of blastocyst versus cleavage stage embryo transfer: a Cochrane review.

UNLABELLED: This paper is based on a Cochrane review published in The Cochrane Library, issue 2, 2002 (see www.CochraneLibrary.net for information) with permission from The Cochrane Collaboration and John Wiley and Sons. Cochrane reviews are regularly updated as new evidence emerges and in response to comments and criticisms, and The Cochrane Library should be consulted for the most recent version of the review. BACKGROUND: The aim of this study was to determine the relative merits of blastocyst versus cleavage stage embryo transfer, concerning the chance of pregnancy, live birth, multiple pregnancy and the factors contributing to these primary outcomes, from the best available evidence. METHODS: A systematic review employing the principles of the Cochrane Menstrual Disorders and Subfertility Group was undertaken. Fourteen randomized controlled trials, all comparing day 2/3 with day 5/6 embryo transfer, were included in a meta-analysis. RESULTS: For day 2/3 versus day 5/6 transfer, there was no significant difference in the odds of pregnancy [odds ratio (OR) = 0.91, 95% confidence interval (CI) 0.71-1.17] nor of live birth (OR = 0.83, 95% CI 0.48-1.42) per treated couple. These results were similar whether all trials, only trials with transfer of equal numbers of day 2/3 versus day 5/6, or only trials with transfer of fewer day 5/6 than day 2/3 embryos, were pooled. There was no significant difference in the odds of multiple pregnancy for day 2/3 versus day 5/6 transfer overall (OR 0.77, 95% CI 0.52-1.13) nor when fewer day 5/6 than day 2/3 embryos were transferred (day 2/3 versus day 5/6 OR 0.69, 95% CI 0.42-1.12). CONCLUSION: The current evidence fails to support a widespread change of practice from cleavage stage to blastocyst stage embryo transfer in couples undergoing IVF.

Blastocyst↗
PubMed2003

Bradykinin causes hypotension by activating pulmonary sympathetic afferents in the rabbit.

Bradykinin (BK) activates sympathetic afferents in the heart, intestine, and kidney, and it alters hemodynamics. However, we know little about the influence of pulmonary sympathetic afferents on circulation. Activation of pulmonary afferents by directly injecting stimulants into the lung parenchyma permits examination of reflexes that originate in the lung without confounding effects from the systemic circulation. In the present study, we tested the hypothesis that pulmonary sympathetic afferents exert a significant influence on hemodynamics. We examined reflex effects of injecting BK (1 microg/kg in 0.1 ml) into the lung parenchyma on circulation in anesthetized, open-chest, artificially ventilated rabbits. BK significantly decreased mean arterial blood pressure (BP) (27 +/- 3 mmHg) and heart rate (19 +/- 4 beats/min). Both effects remained after bilateral vagotomy. To rule out possible direct systemic vasodilation by BK, we examined renal sympathetic nerve activity (RSNA) in response to BK injection and examined BP responses to injection of ACh (0.1 ml of 10-4 M). BK suppressed the RSNA before and after vagotomy. ACh did not change BP when injected into the lung parenchyma, but it decreased BP (31 +/- 3 mmHg) when injected into the right atrium. Our data indicate that activating pulmonary sympathetic afferents reflexly suppresses hemodynamics.

Acetylcholine↗
PubMed2003

Gaps in the evidence for fertility treatment-an analysis of the Cochrane Menstrual Disorders and Subfertility Group database.

BACKGROUND: The randomized controlled trial is considered the best approach to assess the effectiveness of treatments. The aim was to summarize the available evidence and determine gaps in the evidence for clinical decision making in subfertility. METHODS: A search of the Cochrane Library for Menstrual Disorders and Subfertility Group reviews was undertaken and, where the reviews were related to subfertility, the authors' conclusions were appraised and correlated with the results and meta-analysis sections of the reviews. Each review was then categorized as to what extent it had answered the clinical question posed by the reviewers. RESULTS: Of 38 subfertility reviews currently or previously published on the Cochrane Library from the Menstrual Disorders and Subfertility Group, 12 reviews concluded that there was evidence of effectiveness of the interventions studied. There was insufficient evidence of effectiveness in 26 reviews, from which the authors of 23 reviews called for further research. A tabulated summary of the review conclusions is presented. CONCLUSION: Cochrane subfertility reviews have eliminated some gaps in the evidence and highlighted others. Future clinical trial design should focus on adequate power and reporting the major outcome of live-births per couple as well as adverse events.

Databases, Factual↗
PubMed2002

Cleavage stage versus blastocyst stage embryo transfer in assisted conception.

BACKGROUND: Despite numerous advances in the field of in vitro fertilisation (IVF), many of the widely applied embryo culture techniques and resulting implantation rates have remained relatively unchanged since the first treatment was performed in the mid 1970's. Recent advances in the understanding of nutrient requirements of embryos, have led to a renaissance of extending their culture from the standard procedure of 2-3 days (early cleavage embryo transfer) to 5-6 days (blastocyst culture). The rationale for blastocyst culture is to improve the synchronicity of uterine and embryonic development and provide a mechanism for self-selection of viable embryos. Numerous reports on the clinical benefits of blastocyst culture have led to the worldwide introduction of this technique, despite a deficiency of conclusive evidence to do so. OBJECTIVES: Primary: To determine if blastocyst stage embryo transfers (ET's) result in higher success rates, than cleavage stage embryo transfers. Secondary: To assess the overall embryo utilisation rate of both techniques. SEARCH STRATEGY: Electronic searches of the Cochrane Menstrual Disorders and Subfertility Group specialised register of controlled trials, CCTR, MEDLINE, EMBASE, and Bio extracts were performed to identify relevant randomised controlled trials (RCTs). Attempts were also made to identify trials from the National Research Register, the Clinical Trial Register and the citation lists of review articles and included trials. The first or corresponding author of each included trial was also contacted for additional information. SELECTION CRITERIA: Trials were included if they were randomised and compared the effectiveness of early cleavage versus blastocyst stage transfers. DATA COLLECTION AND ANALYSIS: Of the 29 trials that were identified, ten trials met the inclusion criteria and were reviewed. Primary outcomes were rates of; live birth, clinical pregnancy and implantation per woman. Secondary outcomes were rates of; miscarriage, monozygotic twinning, embryo freezing, embryo utilisation, cancellation, multiple pregnancy and high order pregnancy and per cycle data. Quality assessment and data extraction were performed independently by two reviewers. Meta analysis was performed using odds ratios for dichotomous outcomes and weighted mean differences for continuous outcomes. MAIN RESULTS: There was no significant difference between the two treatment groups in live birth rate, although this was reported by only one quasi-random trial (Peto OR 1.59, 95% CI 0.80, 3.15). There was also no evidence of a difference in pregnancy rate (both overall and subgroups) between the two groups for pregnancy rate per couple randomised (4 RCTs: Peto OR 0.86, 95% CI 0.57, 1.29). There was also no suggestion of an overall difference in implantation rates per embryo's transferred although it was impossible to calculate valid confidence intervals from published data (Day 2/3 17.1% vs Day 5/6 18.9%). The subgroup of sequential media trials suggested higher implantation rate for blastocyst transfer (Day 2/3 22.6% vs Day 5/6 32%). The miscarriage rate was no different between the two groups (1 RCT, Peto OR 1.66, 95% CI 0.41, 6.81). The RCTs reporting embryo freezing showed no difference (Peto OR 1.71, 95% CI 1.00, 2.94), however the two quasi-random trials showed a significant difference in favour of the Day 2/3 group (Peto OR 2.99, 95% CI 1.88, 4.75). Embryo transfer cancellation rates were significantly higher in the Day 5/6 group (5 RCTs: Peto OR 0.57, 95% CI 0.40, 0.83). There was no significant difference in the rate of multiple pregnancies or the rate of high order pregnancies (3 RCTs, Peto OR 0.58, 95% CI 0.30, 1.12)(2 RCTs, Peto OR 7.88, 95% CI 0.49, 126.30 respectively). REVIEWER'S CONCLUSIONS: Overall this review of the best available evidence based on data from randomised controlled trials, suggests that to date little difference in the major outcome parameters has been demonstrated between early embryo transfer and blastocyst culture. Collectively, the increase in cancellation and the possible decrease in cryopreservation rates suggest that the routine practice of blastocyst culture should be offered to patients with caution. The subgroup of trials employing sequential media, did however demonstrate a substantial improvement in implantation rates and similar pregnancy rates, despite the transfer of less embryos. Whether this trend will culminate in convincing higher live birth rates per woman, has yet to be validated.

Blastocyst↗
PubMed2002

Oral versus injectable ovulation induction agents for unexplained subfertility.

BACKGROUND: Oral (anti-oestrogens) and injectable (gonadotrophins) ovulation induction agents have been used to increase the number of eggs produced by a woman per cycle in treatment for unexplained subfertility. It is unclear whether there are significant advantages of one type of treatment over the other in this context or in terms of fertility. OBJECTIVES: To assess the efficacy of oral versus injectable ovulation induction agents for unexplained subfertility. SEARCH STRATEGY: The search strategy of the Menstrual Disorders and Subfertility Group was used for the identification of relevant randomised controlled trials. SELECTION CRITERIA: All trials where oral ovulation induction agents were compared with injectable ovulation induction agents in treatment groups generated by randomisation, from couples with unexplained subfertility, were considered for inclusion in the review. DATA COLLECTION AND ANALYSIS: Five randomised controlled trials, including a total of 231 identified couples with unexplained subfertility, were found and included in this review. All trials were assessed for quality criteria. The studied outcomes were pregnancy, live birth, miscarriage, multiple birth, occurrence of ovarian hyperstimulation syndrome and cycle cancellation. MAIN RESULTS: Where trials with important co-interventions were excluded, there was no significant difference in the odds of beneficial outcomes for oral versus injectable ovulation induction agents - live birth per couple (OR 0.06, 95%CI 0.00-1.15), pregnancy per woman (OR 0.33, 95%CI 0.09-1.20); nor of detrimental outcomes for injectable versus oral agents - miscarriage (OR 0.11, 95%CI 0.00-2.84); there were no reported cases of multiple births, cases of ovarian hyperstimulation or discontinued cycles consequent upon overstimulation. Where trials with the co-intervention of a human chorionic gonadotrophin trigger injection (given only in the injectable ovulation induction agent treatment arm) were not excluded there was no significant difference in the odds of live birth per couple (OR 0.40, 95%CI 0.15-1.08). However oral ovulation induction agents had significantly reduced odds of pregnancy per woman compared to injectable ovulation induction agents (OR 0.41, 95%CI 0.17-0.80). For detrimental outcomes, there were no significant differences in the odds of miscarriage (OR 0.61, 95%CI 0.09-4.01) and multiple birth (OR 1.08, 95%CI 0.16-7.03) for injectable versus oral agents. No data were available concerning the occurrence of ovarian hyperstimulation syndrome nor cycle cancellation. REVIEWER'S CONCLUSIONS: There is insufficient evidence to suggest that oral agents are inferior or superior to injectable agents in the treatment of unexplained subfertility. Information on harms is sketchy, and remains compatible with large differences in either direction. Much larger trials than have previously been undertaken are required to provide information on relative harms as well as benefits.

Administration, Oral↗
PubMed2001

The UBX domain: a widespread ubiquitin-like module.

The UBX domain is an 80 amino acid residue module that is present typically at the carboxyl terminus of a variety of eukaryotic proteins. In an effort to elucidate the function of UBX domains, we solved the three-dimensional structure of the UBX domain of human Fas-associated factor-1 (FAF1) by NMR spectroscopy. The structure has a beta-Grasp fold characterised by a beta-beta-alpha-beta-beta-alpha-beta secondary-structure organisation. The five beta strands are arranged into a mixed sheet in the order 21534. The longer first helix packs across the first three strands of the sheet, and a second shorter 3(10) helix is located in an extended loop connecting strands 4 and 5. In the absence of significant sequence similarity, the UBX domain can be superimposed with ubiquitin with an r.m.s.d. of 1.9 A, suggesting that the two structures share the same superfold, and an evolutionary relationship. However, the absence of a carboxyl-terminal extension containing a double glycine motif and of suitably positioned lysine side-chains makes it highly unlikely that UBX domains are either conjugated to other proteins or part of mixed UBX-ubiquitin chains. Database searches revealed that most UBX domain-containing proteins belong to one of four evolutionarily conserved families represented by the human FAF1, p47, Y33K, and Rep8 proteins. A role of the UBX domain in ubiquitin-related processes is suggested.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Eight blue babies.

Methemoglobinemia is a serious medical condition that affects hundreds of infants in the United States each year. The condition involves the oxidation of red cell hemoglobin to a state that is unable to transport oxygen. Affected infants appear cyanotic and may have altered mental status. The condition is readily reversible if recognized and treated appropriately. The Wisconsin Division of Public Health investigates all cases of infant methemoglobinemia in an attempt to determine their cause. Between January 1990 and September 1999, 8 infants were diagnosed with this condition. Review of their hospitalization records found that 3 of these cases involved infants whose formula was prepared with water from nitrate-contaminated wels. Risk factors identified in the remaining cases included use of folk remedies, misuse of over-the-counter analgesics, and an inherited enzyme deficiency. Causes were not identified for 2 of the cases. All of the affected infants recovered.

Diagnosis, Differential↗
PubMed2000

Biophysical characterization of elongin C from Saccharomyces cerevisiae.

Elongin C (ELC) is an essential component of the mammalian CBC(VHL) E3 ubiquitin ligase complex. As a step toward understanding the role of ELC in assembly and function of CBC-type ubiquitin ligases, we analyzed the quaternary structure and backbone dynamics of the highly homologous Elc1 protein from Saccharomyces cerevisiae. Analytical ultracentrifugation experiments in conjunction with size exclusion chromatography showed that Elc1 is a nonglobular monomer over a wide range of concentrations. Pronounced line broadening in (1)H,(15)N-HSQC NMR spectra and failure to assign peaks corresponding to the carboxy-terminal helix 4 of Elc1 indicated that helix 4 is conformationally labile. Measurement of (15)N NMR relaxation parameters including T(1), T(2), and the (1)H-(15)N nuclear Overhauser effect revealed (i) surprisingly high flexibility of residues 69-77 in loop 5, and (ii) chemical exchange contributions for a large number of residues throughout the protein. Addition of 2,2,2-trifluoroethanol (TFE) stabilized helix 4 and reduced chemical exchange contributions, suggesting that stabilization of helix 4 suppresses the tendency of Elc1 to undergo conformational exchange on a micro- to millisecond time scale. Binding of a peptide representing the major ELC binding site of the von Hippel-Lindau (VHL) tumor suppressor protein almost completely eliminated chemical exchange processes, but induced substantial conformational changes in Elc1 leading to pronounced rotational anisotropy. These results suggest that elongin C interacts with various target proteins including the VHL protein by an induced fit mechanism involving the conformationally flexible carboxy-terminal helix 4.

Amino Acid Sequence↗
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

Nurses' knowledge of palliative care in the Australian Capital Territory.

Australia has a growing number of specialist palliative care services. As they expanded in the Australian Capital Territory, a working party was established to discuss issues associated with palliative care. One activity authorized by this committee was a survey of nurses' knowledge of palliative care. The Palliative Care Quiz for Nurses (Ross et al, 1996) was adapted with permission for this survey: 455 registered and enrolled nurses were surveyed; 247 (54%) participants returned completed questionnaires. The overall mean score for the Palliative Care Quiz was 12.4 of a possible 20; the mean scores were 13.2 for registered nurses and 10.6 for enrolled nurses. Nurses with some oncology or palliative care experience scored significantly higher than others. Nurses with more work experience as measured by working years also attained significantly higher scores. Analysis and examination of correct items suggest that nurses have acquired basic knowledge through experience. However, as other studies have suggested, there is also a lack of knowledge of complex symptoms found in palliative care patients.

Adaptation, Psychological↗
PubMed2000

Antibiotic susceptibility of invasive Streptococcus pneumoniae in Wisconsin, 1999.

BACKGROUND: Streptococcus pneumoniae is a major cause of community acquired infections in the United States, and rates of antibiotic resistance have increased dramatically in the past decade. Statewide rates of pneumococcal resistance to penicillin and other antibiotics have not been previously reported in Wisconsin. To determine these rates, we assessed invasive pneumococcal isolates for reduced susceptibility to nine different antibiotics. METHODS: Pneumococcal isolates from blood, cerebrospinal fluid or other normally sterile body sites were submitted by 91% of laboratories that perform invasive bacterial cultures. Isolates were tested for susceptibility to penicillin, cefotaxime, ceftriaxone, levofloxacin, meropenem, erythromycin, vancomycin, sulfamethoxazole-trimethoprim and chloramphenicol. RESULTS: There were 409 invasive pneumococcal isolates identified in 1999 among Wisconsin residents, including 385 (94%) isolates from blood. The mean patient age was 42.5 years (range, < 1 year to 96 years), and 213 (52%) were male. Of the pneumococcal isolates, 24% were not susceptible to penicillin, including 10% with high level resistance. Isolates with reduced penicillin susceptibility were also likely to have reduced susceptibility to other antibiotics. Patients with penicillin nonsusceptible (intermediate and fully resistant) pneumococcal isolates were significantly younger (mean, 37.0 years) than those with susceptible isolates (mean, 44.3 years) (p = .04). The proportion of patients with a penicillin nonsusceptible isolate varied by region, ranging from 12.8% in northeastern Wisconsin to 35.5% in northern Wisconsin. CONCLUSIONS: The proportion of invasive pneumococcal isolates with penicillin resistance in Wisconsin is similar to other regions of the United States. Inappropriate antibiotic use contributes to the emergence of resistant pneumococcal infections, and educational efforts are underway to promote judicious antibiotic use in Wisconsin.

Adolescent↗
PubMed1999

Structural changes in the transition state of protein folding: alternative interpretations of curved chevron plots.

The interpretation of folding rates is often rationalized within the context of transition state theory. This means that the reaction rate is linked to an activation barrier, the height of which is determined by the free energy difference between a ground state (the starting point) and an apparent transition state. Changes in the folding kinetics are thus caused by effects on either the ground state, the transition state, or both. However, structural changes of the transition state are rarely discussed in connection with experimental data, and kinetic anomalies are commonly ascribed to ground state effects alone, e.g., depletion or accumulation of structural intermediates upon addition of denaturant. In this study, we present kinetic data which are best described by transition state changes. We also show that ground state effects and transition state effects are in general difficult to distinguish kinetically. The analysis is based on the structurally homologous proteins U1A and S6. Both proteins display two-state behavior, but there is a marked difference in their kinetics. S6 exhibits a classical V-shaped chevron plot (log observed rate constant vs denaturant concentration), whereas U1A's chevron plot is symmetrically curved, like an inverted bell curve. However, S6 is readily mutated to display U1A-like kinetics. The seemingly drastic effects of these mutations are readily ascribed to transition state movements where large kinetic differences result from relatively small alterations of a common free energy profile and broad activation barriers.

Amino Acid Sequence↗
PubMed1999

Pulmonary edema develops after recurrent obstructive apneas.

There are anecdotal reports of pulmonary edema after a night of recurrent obstructive apneas (OAs) in humans, but no data on lung water, gas exchange, filling pressure, or cardiac output (Q) exist in these patients. By clamping the endotracheal tube of eight intubated, anesthesized dogs, we created repetitive OAs of 45-s duration at 30-s intervals, for 8 h. Five additional dogs without apneas, but identically instrumented, were studied simultaneously, serving as nonapneic controls. Sa (O(2)) was measured by intraarterial catheter, pulmonary capillary wedge pressure (Pcw), continuous cardiac output (Q), and mixed venous oxygen saturation (Sv(O(2))) were measured by flotation catheter. Basal and hourly hemodynamics and blood gases (arterial and venous) under steady state respiration were measured. Venous admixture (Q S/Q T) was calculated by standard equations. Pa(O(2)) from the beginning to the end of the experiment fell from 89.6 to 82.8 mm Hg in apneic animals and from 92.2 to 85.5 mm Hg in controls. The Q S/Q T increased in both groups but more so in the apnea group (3.3 to 19.4%) than in nonapneic controls (3.1 to 7.9%). Neither Q nor Pcw changed significantly in either group. Lung wet/dry weight was 5.40 +/- 0.93 in apneic animals and 5.00 +/- 0.67 in controls. Light microscopy showed gross alveolar fluid in three apneic dogs, and electron microscopy showed interstitial fluid in two additional apneic dogs. One of the lung edema dogs expired of acute heart failure in the seventh hour of the experiment. Worsening of gas exchange and histology suggest that lung edema can result from recurrent OAs.

Animals↗
PubMed1998

BAP1: a novel ubiquitin hydrolase which binds to the BRCA1 RING finger and enhances BRCA1-mediated cell growth suppression.

We have identified a novel protein, BAP1, which binds to the RING finger domain of the Breast/Ovarian Cancer Susceptibility Gene product, BRCA1. BAP1 is a nuclear-localized, ubiquitin carboxy-terminal hydrolase, suggesting that deubiquitinating enzymes may play a role in BRCA1 function. BAP1 binds to the wild-type BRCA1-RING finger, but not to germline mutants of the BRCA1-RING finger found in breast cancer kindreds. BAP1 and BRCA1 are temporally and spatially co-expressed during murine breast development and remodeling, and show overlapping patterns of subnuclear distribution. BAP1 resides on human chromosome 3p21.3; intragenic homozygous rearrangements and deletions of BAP1 have been found in lung carcinoma cell lines. BAP1 enhances BRCA1-mediated inhibition of breast cancer cell growth and is the first nuclear-localized ubiquitin carboxy-terminal hydrolase to be identified. BAP1 may be a new tumor suppressor gene which functions in the BRCA1 growth control pathway.

Amino Acid Sequence↗