46 research outputs found
Phylogenetic and functional marker genes to study ammonia-oxidizing microorganisms (AOM) in the environment
The oxidation of ammonia plays a significant role in the transformation of fixed nitrogen in the global nitrogen cycle. Autotrophic ammonia oxidation is known in three groups of microorganisms. Aerobic ammonia-oxidizing bacteria and archaea convert ammonia into nitrite during nitrification. Anaerobic ammonia-oxidizing bacteria (anammox) oxidize ammonia using nitrite as electron acceptor and producing atmospheric dinitrogen. The isolation and cultivation of all three groups in the laboratory are quite problematic due to their slow growth rates, poor growth yields, unpredictable lag phases, and sensitivity to certain organic compounds. Culture-independent approaches have contributed importantly to our understanding of the diversity and distribution of these microorganisms in the environment. In this review, we present an overview of approaches that have been used for the molecular study of ammonia oxidizers and discuss their application in different environments
Developing a core outcome set for future infertility research: an international consensus development study
Study Question
Can a core outcome set to standardize outcome selection, collection, and reporting across future infertility research be developed?
Summary Answer
A minimum data set, known as a core outcome set, has been developed for randomized controlled trials (RCT) and systematic reviews evaluating potential treatments for infertility.
What is Known Already
Complex issues, including a failure to consider the perspectives of people with fertility problems when selecting outcomes, variations in outcome definitions, and the selective reporting of outcomes on the basis of statistical analysis, make the results of infertility research difficult to interpret.
Study Design, Size, Duration
A three-round Delphi survey (372 participants from 41 countries) and consensus development workshop (30 participants from 27 countries).
Participants/Materials, Setting, Methods
Healthcare professionals, researchers, and people with fertility problems were brought together in an open and transparent process using formal consensus science methods.
Main Results and the Role of Chance
The core outcome set consists of: viable intrauterine pregnancy confirmed by ultrasound (accounting for singleton, twin, and higher multiple pregnancy); pregnancy loss (accounting for ectopic pregnancy, miscarriage, stillbirth, and termination of pregnancy); live birth; gestational age at delivery; birthweight; neonatal mortality; and major congenital anomaly. Time to pregnancy leading to live birth should be reported when applicable.
Limitations, Reasons for Caution
We used consensus development methods which have inherent limitations, including the representativeness of the participant sample, Delphi survey attrition, and an arbitrary consensus threshold.
Wider Implications of the Findings
Embedding the core outcome set within RCTs and systematic reviews should ensure the comprehensive selection, collection, and reporting of core outcomes. Research funding bodies, the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) statement, and over 80 specialty journals, including the Cochrane Gynaecology and Fertility Group, Ferility and Sterility, and Human Reproduction, have committed to implementing this core outcome set
Standardizing definitions and reporting guidelines for the infertility core outcome set: an international consensus development study
Study Question
Can consensus definitions for the core outcome set for infertility be identified in order to recommend a standardized approach to reporting?
Summary Answer
Consensus definitions for individual core outcomes, contextual statements, and a standardized reporting table have been developed.
What is Known Already
Different definitions exist for individual core outcomes for infertility. This variation increases the opportunities for researchers to engage with selective outcome reporting, which undermines secondary research and compromises clinical practice guideline development.
Study Design, Size, Duration
Potential definitions were identified by a systematic review of definition development initiatives and clinical practice guidelines and by reviewing Cochrane Gynaecology and Fertility Group guidelines. These definitions were discussed in a face-to-face consensus development meeting, which agreed consensus definitions. A standardized approach to reporting was also developed as part of the process.
Participants/Materials, Setting, Methods
Healthcare professionals, researchers, and people with fertility problems were brought together in an open and transparent process using formal consensus development methods.
Main Results and the Role of Chance
Forty-four potential definitions were inventoried across four definition development initiatives, including the Harbin Consensus Conference Workshop Group and International Committee for Monitoring Assisted Reproductive Technologies, 12 clinical practice guidelines, and Cochrane Gynaecology and Fertility Group guidelines. Twenty-seven participants, from 11 countries, contributed to the consensus development meeting. Consensus definitions were successfully developed for all core outcomes. Specific recommendations were made to improve reporting.
Limitations, Reasons for Caution
We used consensus development methods, which have inherent limitations. There was limited representation from low- and middle-income countries.
Wider Implications of the Findings
A minimum data set should assist researchers in populating protocols, case report forms, and other data collection tools. The generic reporting table should provide clear guidance to researchers and improve the reporting of their results within journal publications and conference presentations. Research funding bodies, the Standard Protocol Items: Recommendations for Interventional Trials statement, and over 80 specialty journals have committed to implementing this core outcome set
Developing a core outcome set for future infertility research: an international consensus development study
STUDY QUESTION
Can a core outcome set to standardize outcome selection, collection and reporting across future infertility research be developed?
SUMMARY ANSWER
A minimum data set, known as a core outcome set, has been developed for randomized controlled trials (RCTs) and systematic reviews evaluating potential treatments for infertility.
WHAT IS KNOWN ALREADY
Complex issues, including a failure to consider the perspectives of people with fertility problems when selecting outcomes, variations in outcome definitions and the selective reporting of outcomes on the basis of statistical analysis, make the results of infertility research difficult to interpret.
STUDY DESIGN, SIZE, DURATION
A three-round Delphi survey (372 participants from 41 countries) and consensus development workshop (30 participants from 27 countries).
PARTICIPANTS/MATERIALS, SETTING, METHODS
Healthcare professionals, researchers and people with fertility problems were brought together in an open and transparent process using formal consensus science methods.
MAIN RESULTS AND THE ROLE OF CHANCE
The core outcome set consists of: viable intrauterine pregnancy confirmed by ultrasound (accounting for singleton, twin and higher multiple pregnancy); pregnancy loss (accounting for ectopic pregnancy, miscarriage, stillbirth and termination of pregnancy); live birth; gestational age at delivery; birthweight; neonatal mortality; and major congenital anomaly. Time to pregnancy leading to live birth should be reported when applicable.
LIMITATIONS, REASONS FOR CAUTION
We used consensus development methods which have inherent limitations, including the representativeness of the participant sample, Delphi survey attrition and an arbitrary consensus threshold.
WIDER IMPLICATIONS OF THE FINDINGS
Embedding the core outcome set within RCTs and systematic reviews should ensure the comprehensive selection, collection and reporting of core outcomes. Research funding bodies, the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) statement, and over 80 specialty journals, including the Cochrane Gynaecology and Fertility Group, Fertility and Sterility and Human Reproduction, have committed to implementing this core outcome set.
STUDY FUNDING/COMPETING INTEREST(S)
This research was funded by the Catalyst Fund, Royal Society of New Zealand, Auckland Medical Research Fund and Maurice and Phyllis Paykel Trust. The funder had no role in the design and conduct of the study, the collection, management, analysis or interpretation of data, or manuscript preparation. B.W.J.M. is supported by a National Health and Medical Research Council Practitioner Fellowship (GNT1082548). S.B. was supported by University of Auckland Foundation Seelye Travelling Fellowship. S.B. reports being the Editor-in-Chief of Human Reproduction Open and an editor of the Cochrane Gynaecology and Fertility group. J.L.H.E. reports being the Editor Emeritus of Human Reproduction. J.M.L.K. reports research sponsorship from Ferring and Theramex. R.S.L. reports consultancy fees from Abbvie, Bayer, Ferring, Fractyl, Insud Pharma and Kindex and research sponsorship from Guerbet and Hass Avocado Board. B.W.J.M. reports consultancy fees from Guerbet, iGenomix, Merck, Merck KGaA and ObsEva. C.N. reports being the Co Editor-in-Chief of Fertility and Sterility and Section Editor of the Journal of Urology, research sponsorship from Ferring, and retains a financial interest in NexHand. A.S. reports consultancy fees from Guerbet. E.H.Y.N. reports research sponsorship from Merck. N.L.V. reports consultancy and conference fees from Ferring, Merck and Merck Sharp and Dohme. The remaining authors declare no competing interests in relation to the work presented. All authors have completed the disclosure form
Standardizing definitions and reporting guidelines for the infertility core outcome set: an international consensus development study
STUDY QUESTION
Can consensus definitions for the core outcome set for infertility be identified in order to recommend a standardized approach to reporting?
SUMMARY ANSWER
Consensus definitions for individual core outcomes, contextual statements and a standardized reporting table have been developed.
WHAT IS KNOWN ALREADY
Different definitions exist for individual core outcomes for infertility. This variation increases the opportunities for researchers to engage with selective outcome reporting, which undermines secondary research and compromises clinical practice guideline development.
STUDY DESIGN, SIZE, DURATION
Potential definitions were identified by a systematic review of definition development initiatives and clinical practice guidelines and by reviewing Cochrane Gynaecology and Fertility Group guidelines. These definitions were discussed in a face-to-face consensus development meeting, which agreed consensus definitions. A standardized approach to reporting was also developed as part of the process.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Healthcare professionals, researchers and people with fertility problems were brought together in an open and transparent process using formal consensus development methods.
MAIN RESULTS AND THE ROLE OF CHANCE
Forty-four potential definitions were inventoried across four definition development initiatives, including the Harbin Consensus Conference Workshop Group and International Committee for Monitoring Assisted Reproductive Technologies, 12 clinical practice guidelines and Cochrane Gynaecology and Fertility Group guidelines. Twenty-seven participants, from 11 countries, contributed to the consensus development meeting. Consensus definitions were successfully developed for all core outcomes. Specific recommendations were made to improve reporting.
LIMITATIONS, REASONS FOR CAUTION
We used consensus development methods, which have inherent limitations. There was limited representation from low- and middle-income countries.
WIDER IMPLICATIONS OF THE FINDINGS
A minimum data set should assist researchers in populating protocols, case report forms and other data collection tools. The generic reporting table should provide clear guidance to researchers and improve the reporting of their results within journal publications and conference presentations. Research funding bodies, the Standard Protocol Items: Recommendations for Interventional Trials statement, and over 80 specialty journals have committed to implementing this core outcome set
Transient response of sandwich plate with transversely flexible and viscoelastic frequency-dependent material core based on a three-layered theory
Effect of valine on 5-HT-mediated prolactin release in healthy volunteers, and on mood in remitted depressed patients.
BACKGROUND: Animal experimental studies suggest that the amino acid valine may decrease brain serotonin (5-HT) function by inhibiting the transport of the 5-HT precursor, L-tryptophan, across the blood barrier. The aim of the present study was to assess whether valine could decrease brain 5-HT function in healthy subjects and provoke symptomatic relapse in recently remitted depressed patients taking antidepressant drug treatment. METHOD: We studied the effect of valine (30 g) on the prolactin (PRL) response to the 5-HT releasing agent, D-fenfluramine, in healthy male subjects and on the mood of 12 remitted depressed patients taking either selective serotonin re-uptake inhibitors (n = 10) or lithium and amitriptyline (n = 2). RESULTS: Valine significantly lowered the PRL response to D-fenfluramine in healthy subjects. In the remitted depressives, valine caused a mild but detectable lowering of mood on a number of measures but only one patient experienced a significant relapse in mood. CONCLUSIONS: Valine administration may decrease brain 5-HT neurotransmission in humans. This effect could explain the mild increase in depressive symptoms in patients taking 5-HT-potentiating drugs