504 research outputs found

    Osteocytes and mechanical loading: The Wnt connection

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    Bone adapts to the mechanical forces that it experiences. Orthodontic tooth movement harnesses the cell‐ and tissue‐level properties of mechanotransduction to achieve alignment and reorganization of the dentition. However, the mechanisms of action that permit bone resorption and formation in response to loads placed on the teeth are incompletely elucidated, though several mechanisms have been identified. Wnt/Lrp5 signalling in osteocytes is a key pathway that modulates bone tissue's response to load. Numerous mouse models that harbour knock‐in, knockout and transgenic/overexpression alleles targeting genes related to Wnt signalling point to the necessity of Wnt/Lrp5, and its localization to osteocytes, for proper mechanotransduction in bone. Alveolar bone is rich in osteocytes and is a highly mechanoresponsive tissue in which components of the canonical Wnt signalling cascade have been identified. As Wnt‐based agents become clinically available in the next several years, the major challenge that lies ahead will be to gain a more complete understanding of Wnt biology in alveolar bone so that improved/expedited tooth movement becomes a possibility

    Costs and Consequences of the Family Nurse Partnership (FNP) Programme in England: Evidence from the Building Blocks Trial

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    Background: The Family Nurse Partnership (FNP) is a licensed intensive home visiting intervention programme delivered to teenage mothers which was originally introduced in England in 2006 by the Department of Health and is now provided through local commissioning of public health services and supported by a national unit led by a consortium of partners. The Building Blocks (BB) trial aimed to explore the effectiveness and cost-effectiveness of this programme. This paper reports the results of an economic evaluation of the Building Blocks randomised controlled trial (RCT) based on a cost-consequence approach. Methods: A large sample of 1618 families was followed-up at various intervals during pregnancy and for two years after birth. A cost-consequence approach was taken to appraise the full range of costs arising from the intervention including both health and social measures of cost alongside the consequences of the trial, specifically, the primary outcomes. Results: A large number of potential factors were identified that are likely to attract additional costs beyond the implementation costs of the intervention including both health and non-health outcomes. Conclusion: Given the extensive costs and only small beneficial consequences observed within the two year follow-up period, the cost-consequence model suggests that the FNP intervention is unlikely to be worth the substantial costs and policy makers may wish to consider other options for investment. Trial registration: ISRCTN23019866 (20/04/2009) Keywords Randomised controlled trial, Cost-consequence analysis, Pregnancy in adolescence, Prenatal care, Maternal health, Home visitin

    PopR: Software for Wildlife Managers

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    It is widely recognized that modern computer software makes wildlife management and research easier and allows increasingly complex tasks to become routine.  Unfortunately, data storage and reporting rarely keep pace with the rapid expansion of data analysis software.  Such disconnects in workflow can lead to missed opportunities where data are not used to their fullest extent and results are slow to emerge.  Here we present a server-based software system, PopR (https://popr.cfc.umt.edu), which merges wildlife management agency databases with state-of-the-art statistical software for real-time wildlife data analysis, population modeling and reporting.  The interface to PopR is a secure website allowing access from any location with internet access and from any platform (personal computer, smartphone, tablet, etc.).  PopR connects to remote data sources through an application program interface (API).  PopR implements Bayesian integrated population models (IPM) combining multiple data sources.  The IPM’s efficiently deal with limited data, overcome missing data and facilitate prediction with error.  PopR also implements individual data source analyses such as survival, sightability and herd composition, among others.  PopR modules are in development or in use in the states of Idaho, Montana and South Dakota where the software is used for a variety of species including deer, elk and mountain lions.  Finally, add-on applications include tools for defining biological populations, checking data integrity and eliciting expert opinion.  The PopR workflow management system promises to streamline data collection, automate routine analyses and generally save managers time while increasing inference from limited data

    Lessons learned from using linked administrative data to evaluate the Family Nurse Partnership in England and Scotland

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    Introduction “Big data” – including linked administrative data – can be exploited to evaluate interventions for maternal and child health, providing time- and cost-effective alternatives to randomised controlled trials. However, using these data to evaluate population-level interventions can be challenging. Objectives We aimed to inform future evaluations of complex interventions by describing sources of bias, lessons learned, and suggestions for improvements, based on two observational studies using linked administrative data from health, education and social care sectors to evaluate the Family Nurse Partnership (FNP) in England and Scotland. Methods We first considered how different sources of potential bias within the administrative data could affect results of the evaluations. We explored how each study design addressed these sources of bias using maternal confounders captured in the data. We then determined what additional information could be captured at each step of the complex intervention to enable analysts to minimise bias and maximise comparability between intervention and usual care groups, so that any observed differences can be attributed to the intervention. Results Lessons learned include the need for i) detailed data on intervention activity (dates/geography) and usual care; ii) improved information on data linkage quality to accurately characterise control groups; iii) more efficient provision of linked data to ensure timeliness of results; iv) better measurement of confounding characteristics affecting who is eligible, approached and enrolled. Conclusions Linked administrative data are a valuable resource for evaluations of the FNP national programme and other complex population-level interventions. However, information on local programme delivery and usual care are required to account for biases that characterise those who receive the intervention, and to inform understanding of mechanisms of effect. National, ongoing, robust evaluations of complex public health evaluations would be more achievable if programme implementation was integrated with improved national and local data collection, and robust quasi-experimental designs

    Development of the Knee Quality of Life (KQoL-26) 26-item questionnaire: data quality, reliability, validity and responsiveness

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    Background This article describes the development and validation of a self-reported questionnaire, the KQoL-26, that is based on the views of patients with a suspected ligamentous or meniscal injury of the knee that assesses the impact of their knee problem on the quality of their lives. Methods Patient interviews and focus groups were used to derive questionnaire content. The instrument was assessed for data quality, reliability, validity, and responsiveness using data from a randomised trial and patient survey about general practitioners' use of Magnetic Resonance Imaging for patients with a suspected ligamentous or meniscal injury. Results Interview and focus group data produced a 40-item questionnaire designed for self-completion. 559 trial patients and 323 survey patients responded to the questionnaire. Following principal components analysis and Rasch analysis, 26 items were found to contribute to three scales of knee-related quality of life: physical functioning, activity limitations, and emotional functioning. Item-total correlations ranged from 0.60–0.82. Cronbach's alpha and test retest reliability estimates were 0.91–0.94 and 0.80–0.93 respectively. Hypothesised correlations with the Lysholm Knee Scale, EQ-5D, SF-36 and knee symptom questions were evidence for construct validity. The instrument produced highly significant change scores for 65 trial patients indicating that their knee was a little or somewhat better at six months. The new instrument had higher effect sizes (range 0.86–1.13) and responsiveness statistics (range 1.50–2.13) than the EQ-5D and SF-36. Conclusion The KQoL-26 has good evidence for internal reliability, test-retest reliability, validity and responsiveness, and is recommended for use in randomised trials and other evaluative studies of patients with a suspected ligamentous or meniscal injury

    Loss of Nmp4 optimizes osteogenic metabolism and secretion to enhance bone quality

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    A goal of osteoporosis therapy is to restore lost bone with structurally sound tissue. Mice lacking the transcription factor Nuclear Matrix Protein 4 (Nmp4, Zfp384, Ciz, ZNF384) respond to several classes of osteoporosis drugs with enhanced bone formation compared to wild type (WT) animals. Nmp4-/- mesenchymal stem/progenitor cells (MSPCs) exhibit an accelerated and enhanced mineralization during osteoblast differentiation. To address the mechanisms underlying this hyper-anabolic phenotype, we carried out RNA-sequencing and molecular and cellular analyses of WT and Nmp4-/- MSPCs during osteogenesis to define pathways and mechanisms associated with elevated matrix production. We determined that Nmp4 has a broad impact on the transcriptome during osteogenic differentiation, contributing to the expression of over 5,000 genes. Phenotypic anchoring of transcriptional data was performed for the hypothesis-testing arm through analysis of cell metabolism, protein synthesis and secretion, and bone material properties. Mechanistic studies confirmed that Nmp4-/- MSPCs exhibited an enhanced capacity for glycolytic conversion- a key step in bone anabolism. Nmp4-/- cells showed elevated collagen translation and secretion. Expression of matrix genes that contribute to bone material-level mechanical properties were elevated in Nmp4-/- cells, an observation that was supported by biomechanical testing of bone samples from Nmp4-/- and WT mice. We conclude that loss of Nmp4 increases the magnitude of glycolysis upon the metabolic switch, which fuels the conversion of the osteoblast into a super-secretor of matrix resulting in more bone with improvements in intrinsic quality

    Patient-reported outcome measures (PROMs) use in post-stroke patient care and clinical practice: a realist synthesis protocol

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    Background There is growing interest in the use of routine patient-reported outcome measures (PROMs) to influence the care of individual patients with stroke. However, there are significant gaps in our understanding as to how PROMs influence post-stroke patient care and clinical practice. This is due to factors including the number of purported uses for PROMs and that PROMs are complex interventions, which attempt to stimulate varied actions or behaviours. Therefore, the objective of this realist synthesis is to offer theory-based explanations as to how PROMs influence post-stroke clinical practice and patient care. Methods This is a protocol for a realist synthesis, which involves three distinct phases: theory building (phase 1), theory testing and refinement (phase 2) and synthesis (phase 3). Phase 1 will develop initial rough programme theories (IRPTs), through literature searches (from January 2000 onwards) of MEDLINE, EMBASE, PsycINFO, CINAHL, Cochrane Library and the grey literature. Only secondary sources will be included that contribute to the development of IRPTs. Only two IRPTs, prioritised by the stakeholder group, will be taken forward to be tested and refined during phase 2. Further novel searches will be employed in phase 2, utilising the same criteria as phase 1; however, phase 2 searches will not utilise grey literature searches, and only primary research studies that contribute to the refinement of programme theories under investigation will be included. Two independent reviewers will screen and select all returned results. The reviewers will code and annotate relevant sources, resulting in ‘fragments’ to be extracted and graded based on the richness of their contribution to explanation and causal insight. Further, these fragments will be organised into ‘Context-Mechanism-Outcome’ configurations. Phase 3 of the review will involve the synthesis of context-mechanism-outcome configurations to form middle-range theory-based explanations and developed logic models for stakeholders to understand how PROMs in post-stroke clinical practice and patient care work for whom, how and under what circumstances. Discussion The resulting realist synthesis will provide guidance on the implementation of PROMs within routine post-stroke clinical practice and patient care and act as a touchstone for further testing and refinement of PROMs programmes

    Development of a core outcome set for the evaluation of interventions to enhance trial participation decisions on behalf of adults who lack capacity to consent: a mixed methods study (COnSiDER Study)

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    Background Trials involving adults who lack capacity to provide consent rely on proxy or surrogate decision-makers, usually a family member, to make decisions about participation. Interventions to enhance proxy decisions about trial participation are now being developed. However, a lack of standardised outcome measures limits evaluation of these interventions. The aim of this study was to establish an agreed standardised core outcome set (COS) for use when evaluating interventions to improve proxy decisions about trial participation. Methods We used established methods to develop the COS including a consensus study with key stakeholder groups comprising those who will use the COS in research (researchers and healthcare professionals) and patients or their representatives. Following a scoping review to identify candidate items, we used a modified two-round Delphi survey to achieve consensus on core outcomes, with equivocal items taken to a consensus meeting for discussion. The COS was finalised following an online consensus meeting in October 2020. Results A total of 28 UK stakeholders (5 researchers, 10 trialists, 3 patient/family representatives, 7 recruiters and 3 advisors/approvers) participated in the online Delphi survey to rank candidate items from the scoping review (n = 36) and additional items proposed by participants (n = 1). Items were broadly grouped into three categories: how family members make decisions, their experiences of making decisions, and the personal aspects that influence the decision. Following the Delphi survey, 27 items were included and ten items exhibited no consensus which required discussion at the consensus meeting. Sixteen participants attended the meeting, including additional patient/family representatives invited to increase representation from this key group (n = 2). We reached consensus for the inclusion of 28 outcome items, including one selected at the consensus meeting. Conclusions The study identified outcomes that should be measured as a minimum in all evaluations of interventions to enhance proxy decisions about trials. These relate to the process of decision-making, proxies’ experience of decision-making, and factors that influence decision-making such as understanding. Further work with people with impairing conditions and their families is needed to explore their views about the COS and to identify appropriate outcome measures and timing of measurement

    Lrp4 Mediates Bone Homeostasis and Mechanotransduction through Interaction with Sclerostin In Vivo

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    Wnt signaling plays a key role in regulating bone remodeling. In vitro studies suggest that sclerostin's inhibitory action on Lrp5 is facilitated by the membrane-associated receptor Lrp4. We generated an Lrp4 R1170W knockin mouse model (Lrp4KI), based on a published mutation in patients with high bone mass (HBM). Lrp4KI mice have an HBM phenotype (assessed radiographically), including increased bone strength and formation. Overexpression of a Sost transgene had osteopenic effects in Lrp4-WT but not Lrp4KI mice. Conversely, sclerostin inhibition had blunted osteoanabolic effects in Lrp4KI mice. In a disuse-induced bone wasting model, Lrp4KI mice exhibit significantly less bone loss than wild-type (WT) mice. In summary, mice harboring the Lrp4-R1170W missense mutation recapitulate the human HBM phenotype, are less sensitive to altered sclerostin levels, and are protected from disuse-induced bone loss. Lrp4 is an attractive target for pharmacological targeting aimed at increasing bone mass and preventing bone loss due to disuse
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