1,289 research outputs found
Perforator mapping reduces the operative time of DIEP flap breast reconstruction: A systematic review and meta-analysis of preoperative ultrasound, computed tomography and magnetic resonance angiography
Background: Prior to DIEP flap breast reconstruction, mapping the perforators of the lower abdominal wall using ultrasound, computed tomography angiography (CTA) or magnetic resonance angiography (MRA) reduces the risk of flap failure. This review aimed to investigate the additional potential benefit of a reduction in operating time.
Methods: We systematically searched the literature for studies concerning adult women undergoing DIEP flap breast reconstruction, which directly compared the operating times and adverse outcomes for those with and without preoperative perforator mapping by ultrasound, CTA or MRA. Outcomes were extracted, data meta-analysed and the quality of the evidence appraised.
Results: Fourteen articles were included. Preoperative perforator mapping by CTA or MRA significantly reduced operating time (mean reduction of 54 minutes [95% CI 3, 105], pâ=â0.04), when directly compared to DIEP flap breast reconstruction with no perforator mapping. Further, perforator mapping by CTA was superior to ultrasound, as CTA saved more time in theatre (mean reduction of 58 minutes [95% CI 25, 91], pâ<â0.001) and was associated with a lower risk of partial flap failure (RR 0.15 [95% CI 0.04, 0.6], pâ=â0.007). All studies were at risk of methodological bias and the quality of the evidence was very low.
Conclusions: The quality of research regarding perforator mapping prior to DIEP flap breast reconstruction is poor and although preoperative angiography appears to save operative time, reduce morbidity and confer cost savings, higher quality research is needed.
Registration: PROSPERO ID CRD42017065012
Quantifying landscape-level methane fluxes in subarctic Finland using a multiscale approach
Journal ArticleQuantifying landscape-scale methane (CH4) fluxes from boreal and arctic regions, and determining how they are controlled, is critical for predicting the magnitude of any CH4 emission feedback to climate change. Furthermore, there remains uncertainty regarding the relative importance of small areas of strong methanogenic activity, vs. larger areas with net CH4 uptake, in controlling landscape-level fluxes. We measured CH4 fluxes from multiple microtopographical subunits (sedge-dominated lawns, interhummocks and hummocks) within an aapa mire in subarctic Finland, as well as in drier ecosystems present in the wider landscape, lichen heath and mountain birch forest. An intercomparison was carried out between fluxes measured using static chambers, up-scaled using a high-resolution landcover map derived from aerial photography and eddy covariance. Strong agreement was observed between the two methodologies, with emission rates greatest in lawns. CH4 fluxes from lawns were strongly related to seasonal fluctuations in temperature, but their floating nature meant that water-table depth was not a key factor in controlling CH4 release. In contrast, chamber measurements identified net CH4 uptake in birch forest soils. An intercomparison between the aerial photography and satellite remote sensing demonstrated that quantifying the distribution of the key CH4 emitting and consuming plant communities was possible from satellite, allowing fluxes to be scaled up to a 100 km2 area. For the full growing season (May to October), ~ 1.1-1.4 g CH4 m-2 was released across the 100 km2 area. This was based on up-scaled lawn emissions of 1.2-1.5 g CH4 m-2, vs. an up-scaled uptake of 0.07-0.15 g CH4 m-2 by the wider landscape. Given the strong temperature sensitivity of the dominant lawn fluxes, and the fact that lawns are unlikely to dry out, climate warming may substantially increase CH4 emissions in northern Finland, and in aapa mire regions in general.This work was carried out within the Natural Environment
Research Council (NERC) funded Arctic Biosphere Atmosphere
Coupling at Multiple Scales (ABACUS) project (a contribution
to International Polar Year 2007_2008) plus NERC small grant
NE/F010222/1 awarded to RB and BH. We are grateful for the support of the staff at the Kevo Subarctic Research Institute, to
David Sayer for operation and maintenance of the eddy covariance
apparatus, and to Lorna English for helping with the
analysis of the CH4 samples. We also thank the NERC Field
Spectroscopy Facility for support in ground data collection for
the remote sensing analysis. Finally, we wish to express our
gratitude to two anonymous reviewers whose comments and
suggestions substantially improved the manuscript
Patient information leaflets (PILs) for UK randomised controlled trials : a feasibility study exploring whether they contain information to support decision making about trial participation
Peer reviewedPublisher PD
The writing on the wall: the concealed communities of the East Yorkshire horselads
This paper examines the graffiti found within late nineteenth and early-twentieth century farm buildings in the Wolds of East Yorkshire. It suggests that the graffiti were created by a group of young men at the bottom of the social hierarchy - the horselads â and was one of the ways in which they constructed a distinctive sense of communal identity, at a particular stage in their lives. Whilst it tells us much about changing agricultural regimes and social structures, it also informs us about experiences and attitudes often hidden from official histories and biographies. In this way, the graffiti are argued to inform our understanding, not only of a concealed community, but also about their hidden histor
Callersâ attitudes and experiences of UK breastfeeding helpline support
Background: Breastfeeding peer support, is considered to be a key intervention for increasing breastfeeding duration rates. Whilst a number of national organisations provide telephone based breastfeeding peer support, to date there have been no published evaluations into callersâ experiences and attitudes of this support. In this study we report on the descriptive and qualitative insights provided by 908 callers as part of an evaluation of UK-based breastfeeding helpline(s).
Methods: A structured telephone interview, incorporating Likert scale responses and open-ended questions was undertaken with 908 callers over May to August, 2011 to explore callersâ experiences of the help and support received via the breastfeeding helpline(s).
Results: Overall satisfaction with the helpline was high, with the vast majority of callersâ recalling positive experiences of the help and support received. Thematic analysis was undertaken on all qualitative and descriptive data recorded during the evaluation, contextualised within the main areas addressed within the interview schedule in terms of âcontact with the helplinesâ; âexperiences of the helpline serviceâ, âperceived effectiveness of support provisionâ and âimpact on caller wellbeingâ.
Conclusion: Callers valued the opportunity for accessible, targeted, non-judgmental and convenient support. Whilst the telephone support did not necessarily influence womenâs breastfeeding decisions, the support they received left them feeling reassured, confident and more determined to continue breastfeeding. We recommend extending the helpline service to ensure support can be accessed when needed, and ongoing training and support for volunteers. Further advertising and promotion of the service within wider demographic groups is warranted
As-yet-uncultivated oral bacteria: breadth and association with oral and extra-oral diseases
It has been shown that 40–60% of the bacteria found in different healthy and diseased oral sites still remain to be grown in vitro, phenotypically characterized, and formally named as species. The possibility exists that these as-yet-uncultivated bacteria play important ecological roles in oral bacterial communities and may participate in the pathogenesis of several oral infectious diseases. There is also a potential for these as-yet-uncultivated oral bacteria to take part in extra-oral infections. For a comprehensive characterization of physiological and pathogenic properties as well as antimicrobial susceptibility of individual bacterial species, strains need to be grown in pure culture. Advances in culturing techniques have allowed the cultivation of several oral bacterial taxa only previously known by a 16S rRNA gene sequence signature, and novel species have been proposed. There is a growing need for developing improved methods to cultivate and characterize the as-yet-uncultivated portion of the oral microbiome so as to unravel its role in health and disease
Neural expression and post-transcriptional dosage compensation of the steroid metabolic enzyme 17β-HSD type 4
<p>Abstract</p> <p>Background</p> <p>Steroids affect many tissues, including the brain. In the zebra finch, the estrogenic steroid estradiol (E<sub>2</sub>) is especially effective at promoting growth of the neural circuit specialized for song. In this species, only the males sing and they have a much larger and more interconnected song circuit than females. Thus, it was surprising that the gene for 17β-hydroxysteroid dehydrogenase type 4 (HSD17B4), an enzyme that converts E<sub>2 </sub>to a less potent estrogen, had been mapped to the Z sex chromosome. As a consequence, it was likely that HSD17B4 was differentially expressed in males (ZZ) and females (ZW) because dosage compensation of Z chromosome genes is incomplete in birds. If a higher abundance of HSD17B4 mRNA in males than females was translated into functional enzyme in the brain, then contrary to expectation, males could produce less E<sub>2 </sub>in their brains than females.</p> <p>Results</p> <p>Here, we used molecular and biochemical techniques to confirm the HSD17B4 Z chromosome location in the zebra finch and to determine that HSD17B4 mRNA and activity were detectable in the early developing and adult brain. As expected, HSD17B4 mRNA expression levels were higher in males compared to females. This provides further evidence of the incomplete Z chromosome inactivation mechanisms in birds. We detected HSD17B4 mRNA in regions that suggested a role for this enzyme in the early organization and adult function of song nuclei. We did not, however, detect significant sex differences in HSD17B4 activity levels in the adult brain.</p> <p>Conclusions</p> <p>Our results demonstrate that the HSD17B4 gene is expressed and active in the zebra finch brain as an E<sub>2 </sub>metabolizing enzyme, but that dosage compensation of this Z-linked gene may occur via post-transcriptional mechanisms.</p
Staying connected: structural integration at the intervertebral discâvertebra interface of human lumbar spines
UNCLES: Method for the identification of genes differentially consistently co-expressed in a specific subset of datasets
Background: Collective analysis of the increasingly emerging gene expression datasets are required. The recently proposed binarisation of consensus partition matrices (Bi-CoPaM) method can combine clustering results from multiple datasets to identify the subsets of genes which are consistently co-expressed in all of the provided datasets in a tuneable manner. However, results validation and parameter setting are issues that complicate the design of such methods. Moreover, although it is a common practice to test methods by application to synthetic datasets, the mathematical models used to synthesise such datasets are usually based on approximations which may not always be sufficiently representative of real datasets. Results: Here, we propose an unsupervised method for the unification of clustering results from multiple datasets using external specifications (UNCLES). This method has the ability to identify the subsets of genes consistently co-expressed in a subset of datasets while being poorly co-expressed in another subset of datasets, and to identify the subsets of genes consistently co-expressed in all given datasets. We also propose the M-N scatter plots validation technique and adopt it to set the parameters of UNCLES, such as the number of clusters, automatically. Additionally, we propose an approach for the synthesis of gene expression datasets using real data profiles in a way which combines the ground-truth-knowledge of synthetic data and the realistic expression values of real data, and therefore overcomes the problem of faithfulness of synthetic expression data modelling. By application to those datasets, we validate UNCLES while comparing it with other conventional clustering methods, and of particular relevance, biclustering methods. We further validate UNCLES by application to a set of 14 real genome-wide yeast datasets as it produces focused clusters that conform well to known biological facts. Furthermore, in-silico-based hypotheses regarding the function of a few previously unknown genes in those focused clusters are drawn. Conclusions: The UNCLES method, the M-N scatter plots technique, and the expression data synthesis approach will have wide application for the comprehensive analysis of genomic and other sources of multiple complex biological datasets. Moreover, the derived in-silico-based biological hypotheses represent subjects for future functional studies.The National Institute for Health Research (NIHR) under its Programme Grants for Applied Research
Programme (Grant Reference Number RP-PG-0310-1004)
A Participatory Health Promotion Mobile App Addressing Alcohol Use Problems (The Daybreak Program): Protocol for a Randomized Controlled Trial
BACKGROUND: At-risk patterns of alcohol use are prevalent in many countries with significant costs to individuals, families, and society. Screening and brief interventions, including with Web delivery, are effective but with limited translation into practice to date. Previous observational studies of the Hello Sunday Morning approach have found that their unique Web-based participatory health communication method has resulted in a reduction of at-risk alcohol use between baseline and 3 months. The Hello Sunday Morning blog program asks participants to publicly set a personal goal to stop drinking or reduce their consumption for a set period of time, and to record their reflections and progress on blogs and social networks. Daybreak is Hello Sunday Morning's evidence-based behavior change program, which is designed to support people looking to change their relationship with alcohol. OBJECTIVE: This study aims to systematically evaluate different versions of Hello Sunday Morning's Daybreak program (with and without coaching support) in reducing at-risk alcohol use. METHODS: We will use a between groups randomized control design. New participants enrolling in the Daybreak program will be eligible to be randomized to receive either (1) the Daybreak program, including peer support plus behavioral experiments (these encourage and guide participants in developing new skills in the areas of mindfulness, connectedness, resilience, situational strategies, and health), or (2) the Daybreak program, including the same peer support plus behavioral experiments, but with online coaching support. We will recruit 467 people per group to detect an effect size of f=0.10. To be eligible, participants must be resident in Australia, aged =18 years, score =8 on the alcohol use disorders identification test (AUDIT), and not report prior treatment for cardiovascular disease. RESULTS: The primary outcome measure will be reduction in the AUDIT-Consumption (AUDIT-C) scores. Secondary outcomes include mental health (Kessler's K-10), days out of role (Kessler), alcohol consumed (measured with a 7-day drinking diary in standard 10 g drinks), and alcohol-related harms (CORE alcohol and drug survey). We will collect data at baseline and 1, 3, and 6 months and analyze them with random effects models, given the correlated data structure. CONCLUSIONS: A randomized trial is required to provide robust evidence of the impact of the online coaching component of the Daybreak program, including over an extended period
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