615 research outputs found
Quantitative Accuracy of Low-Count SPECT Imaging in Phantom and In Vivo Mouse Studies
We investigated the accuracy of a single photon emission computed tomography (SPECT) system in quantifying a wide range of radioactivity concentrations using different scan times in both phantom and animal models. A phantom containing various amounts of In-111 or Tc-99m was imaged until the activity had decayed close to background levels. Scans were acquired for different durations, employing different collimator pinhole sizes. VOI analysis was performed to quantify uptake in the images and the values compared to the true activity. The phantom results were then validated in tumour-bearing mice. The use of an appropriate calibration phantom and disabling of a background subtraction feature meant that absolute errors were within 12% of the true activity. Furthermore, a comparison of in vivo imaging and biodistribution studies in mice showed a correlation of 0.99 for activities over the 200âkBq to 5âMBq range. We conclude that the quantitative information provided by the NanoSPECT camera is accurate and allows replacement of dissection studies for assessment of radiotracer biodistribution in mouse models
IMPaCT Back study protocol. Implementation of subgrouping for targeted treatment systems for low back pain patients in primary care: a prospective population-based sequential comparison.
BACKGROUND: Prognostic assessment tools to identify subgroups of patients at risk of persistent low back pain who may benefit from targeted treatments have been developed and validated in primary care. The IMPaCT Back study is investigating the effects of introducing and supporting a subgrouping for targeted treatment system in primary care. METHODS/DESIGN: A prospective, population-based, quality improvement study in one Primary Care Trust in England with a before and after design. Phases 1 and 3 collect data on current practice, attitudes and behaviour of health care practitioners, patients' outcomes and health care costs. Phase 2 introduces and supports the subgrouping for targeted treatment system, via a multi-component, quality improvement intervention that includes educational courses and outreach visits led by opinion leaders, audit/feedback, mentoring and organisational support to embed the subgrouping tools within IT and clinical management systems.We aim to recruit 1000 low back pain patients aged 18 years and over consulting 7 GP practices within one Primary Care Trust in England, UK. The study includes GPs in participating practices and physiotherapists in associated services. The primary objective is to determine the effect of the subgrouping for targeted treatment system on back pain related disability and catastrophising at 2 and 6 months, comparing data from phase 1 with phase 3. Key secondary objectives are to determine the impact on: a) GPs' and physiotherapists' attitudes and behaviour regarding low back pain; b) The process of care that patients receive; c) The cost-effectiveness and sustainability of the new clinical system. DISCUSSION: This paper details the rationale, design, methods, planned analysis and operational aspects of the IMPaCT Back study. We aim to determine whether the new subgrouping for targeted treatment system is implemented and sustained in primary care, and evaluate its impact on clinical decision-making, patient outcomes and costs. STUDY REGISTRATION: International Standard Randomised Controlled Trial Number Register ISRCTN55174281.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
Sleep in children with type 1 diabetes and their parents in the T1D Exchange
Objectives
Sleep has physiological and behavioral impacts on diabetes outcomes, yet little is known about the impact of sleep disturbances in children with type 1 diabetes. The current study sought to characterize sleep in children with type 1 diabetes and in their parents and to examine the associations between child sleep, glycemic control and adherence, parent sleep and well-being, parental fear of hypoglycemia, and nocturnal caregiving behavior.
Methods
Surveys were emailed to parents of 2- to 12-year-old participants in the Type 1 Diabetes (T1D) Exchange clinic registry. Clinical data were obtained from the registry for the 515 respondents.
Results
In our sample, 67% of children met criteria for poor sleep quality. Child sleep quality was related to glycemic control (HbA1c of 7.9% [63 mmol/mol] in children with poor sleep quality vs 7.6% [60 mmol/mol] in children with non-poor sleep quality; P < 0.001) but not mean frequency of blood glucose monitoring (BGM) (7.6 times/day vs 7.4 in poor/non-poor quality; P = 0.56). Associations were similar for sleep duration. Children with poor sleep quality were more likely to experience severe hypoglycemia (4% in children with poor sleep quality vs 1% in children with non-poor sleep quality; P = 0.05) and more likely to experience DKA (7% vs 4%, respectively; P < 0.001). Poorer child sleep quality was associated with poorer parental sleep quality, parental well-being, and fear of hypoglycemia (P < 0.001 for all). Child sleep was not related to the use of diabetes-related technology (CGM, insulin pump).
Conclusions
Sleep may be a modifiable factor to improve glycemic control and reduce parental distress
The changing nature of managerial work: The effects of corporate restructuring on management jobs and careers
This article analyses contemporary issues relevant to understanding the changing nature of management and managerial work. The argument is developed in four parts. First, to provide context, we offer an overview of the literature on the organization and control of managerial work, tracing contributions mainly from the early 1950s onwards. Second, we discuss the first of two related concerns relevant to understanding the contemporary nature of managerial work â strategies of organizational restructuring: an analysis highlighting the role of downsizing and delayering within corporate campaigns promoting âpost-bureaucraticâ systems. Third, we extend this discussion by addressing how such corporate restructuring affects managers in their everyday work â notably in relation to the perceptions and realities of growing job insecurity and career uncertainty: an analysis that frequently draws upon our own investigations to establish an agenda for future research. The article concludes by summarizing the content of four research articles whose arguments relate to issues discussed in this analysis of managerial work. Keyword
Integrated DNA Copy Number and Expression Profiling Identifies IGF1R as a Prognostic Biomarker in Pediatric Osteosarcoma.
Osteosarcoma is a primary malignant bone tumor arising from bone-forming mesenchymal cells in children and adolescents. Despite efforts to understand the biology of the disease and identify novel therapeutics, the survival of osteosarcoma patients remains dismal. We have concurrently profiled the copy number and gene expression of 226 osteosarcoma samples as part of the Strategic Partnering to Evaluate Cancer Signatures (SPECS) initiative. Our results demonstrate the heterogeneous landscape of osteosarcoma in younger populations by showing the presence of genome-wide copy number abnormalities occurring both recurrently among samples and in a high frequency. Insulin growth factor receptor 1 (IGF1R) is a receptor tyrosine kinase which binds IGF1 and IGF2 to activate downstream pathways involved in cell apoptosis and proliferation. We identify prevalent amplification of IGF1R corresponding with increased gene expression in patients with poor survival outcomes. Our results substantiate previously tenuously associated copy number abnormalities identified in smaller datasets (13q34+, 20p13+, 4q35-, 20q13.33-), and indicate the significance of high fibroblast growth factor receptor 2 (FGFR2) expression in distinguishing patients with poor prognosis. FGFR2 is involved in cellular proliferation processes such as division, growth and angiogenesis. In summary, our findings demonstrate the prognostic significance of several genes associated with osteosarcoma pathogenesis
Gene-resolution analysis of DNA copy number variation using oligonucleotide expression microarrays
<p>Abstract</p> <p>Background</p> <p>Array-based comparative genomic hybridization (aCGH) is a high-throughput method for measuring genome-wide DNA copy number changes. Current aCGH methods have limited resolution, sensitivity and reproducibility. Microarrays for aCGH are available only for a few organisms and combination of aCGH data with expression data is cumbersome.</p> <p>Results</p> <p>We present a novel method of using commercial oligonucleotide expression microarrays for aCGH, enabling DNA copy number measurements and expression profiles to be combined using the same platform. This method yields aCGH data from genomic DNA without complexity reduction at a median resolution of approximately 17,500 base pairs. Due to the well-defined nature of oligonucleotide probes, DNA amplification and deletion can be defined at the level of individual genes and can easily be combined with gene expression data.</p> <p>Conclusion</p> <p>A novel method of gene resolution analysis of copy number variation (graCNV) yields high-resolution maps of DNA copy number changes and is applicable to a broad range of organisms for which commercial oligonucleotide expression microarrays are available. Due to the standardization of oligonucleotide microarrays, graCNV results can reliably be compared between laboratories and can easily be combined with gene expression data using the same platform.</p
Press reslease from the Premier and Tourism Minister, Mr Dunstan: New amenity block for Moonta Bay Caravan Park
Getting rid of the tubes: An assessment of the retention of functionalized multi-walled carbon nanotubes (MWNTs) in the organs of mice was carried out using single photon emission computed tomography and quantitative scintigraphy (see scheme). Increasing the degree of functionalization on MWNTs enhanced renal clearance, while lower functionalization promoted reticuloendethelial system accumulation
Involvement of a eukaryotic-like ubiquitin-related modifier in the proteasome pathway of the archaeon Sulfolobus acidocaldarius.
In eukaryotes, the covalent attachment of ubiquitin chains directs substrates to the proteasome for degradation. Recently, ubiquitin-like modifications have also been described in the archaeal domain of life. It has subsequently been hypothesized that ubiquitin-like proteasomal degradation might also operate in these microbes, since all archaeal species utilize homologues of the eukaryotic proteasome. Here we perform a structural and biochemical analysis of a ubiquitin-like modification pathway in the archaeon Sulfolobus acidocaldarius. We reveal that this modifier is homologous to the eukaryotic ubiquitin-related modifier Urm1, considered to be a close evolutionary relative of the progenitor of all ubiquitin-like proteins. Furthermore we demonstrate that urmylated substrates are recognized and processed by the archaeal proteasome, by virtue of a direct interaction with the modifier. Thus, the regulation of protein stability by Urm1 and the proteasome in archaea is likely representative of an ancient pathway from which eukaryotic ubiquitin-mediated proteolysis has evolved.N.P.R. is grateful to the Department of Biochemistry and the Isaac Newton Trust (Trinity College, Cambridge) for supporting this study. The N.P.R. laboratory is funded by the Medical Research Council [Career Development Award G0701443], and also by an Isaac Newton Trust Research Grant. S.M.B. is supported by a BBSRC Doctoral Training Grant [RG53842]. L.P. and M.L.K were funded by a Wellcome Trust Senior Fellowship Award in Basic Biomedical Sciences [grant no. 08279/Z/07/Z]. S.V.A. was supported by intramural funds of the Max Planck Society.This is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/ncomms916
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