732 research outputs found

    Probability of cancer in lung nodules using sequential volumetric screening up to 12 months: the UKLS trial.

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    BACKGROUND: Estimation of the clinical probability of malignancy in patients with pulmonary nodules will facilitate early diagnosis, determine optimum patient management strategies and reduce overall costs. METHODS: Data from the UK Lung Cancer Screening trial were analysed. Multivariable logistic regression models were used to identify independent predictors and to develop a parsimonious model to estimate the probability of lung cancer in lung nodules detected at baseline and at 3-month and 12-month repeat screening. RESULTS: Of 1994 participants who underwent CT scan, 1013 participants had a total of 5063 lung nodules and 52 (2.6%) of the participants developed lung cancer during a median follow-up of 4 years. Covariates that predict lung cancer in our model included female gender, asthma, bronchitis, asbestos exposure, history of cancer, early and late onset of family history of lung cancer, smoking duration, FVC, nodule type (pure ground-glass and part-solid) and volume as measured by semiautomated volumetry. The final model incorporating all predictors had excellent discrimination: area under the receiver operating characteristic curve (AUC 0.885, 95% CI 0.880 to 0.889). Internal validation suggested that the model will discriminate well when applied to new data (optimism-corrected AUC 0.882, 95% CI 0.848 to 0.907). The risk model had a good calibration (goodness-of-fit χ[8] 8.13, p=0.42). CONCLUSIONS: Our model may be used in estimating the probability of lung cancer in nodules detected at baseline and at 3 months and 12 months from baseline, allowing more efficient stratification of follow-up in population-based lung cancer screening programmes. TRIAL REGISTRATION NUMBER: 78513845.National Institute for Health Research Health Technology Assessment (NIHR HTA) (reference number HTA 09/61/01)

    Northern winter climate change: assessment of uncertainty in CMIP5 projections related to stratosphere-troposphere coupling

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    Journal ArticlePublished versionFuture changes in the stratospheric circulation could have an important impact on northern winter tropospheric climate change, given that sea level pressure (SLP) responds not only to tropospheric circulation variations but also to vertically coherent variations in troposphere-stratosphere circulation. Here we assess northern winter stratospheric change and its potential to influence surface climate change in the Coupled Model Intercomparison Project-Phase 5 (CMIP5) multimodel ensemble. In the stratosphere at high latitudes, an easterly change in zonally averaged zonal wind is found for the majority of the CMIP5 models, under the Representative Concentration Pathway 8.5 scenario. Comparable results are also found in the 1% CO2 increase per year projections, indicating that the stratospheric easterly change is common feature in future climate projections. This stratospheric wind change, however, shows a signi fi cant spread among the models. By using linear regression, we quantify the impact of tropical upper troposphere warming, polar amplification, and the stratospheric wind change on SLP. We find that the intermodel spread in stratospheric wind change contributes substantially to the intermodel spread in Arctic SLP change. The role of the stratosphere in determining part of the spread in SLP change is supported by the fact that the SLP change lags the stratospheric zonally averaged wind change. Taken together, these findings provide further support for the importance of simulating the coupling between the stratosphere and the troposphere, to narrow the uncertainty in the future projection of tropospheric circulation changes

    Ruminal acidosis and the rapid onset of ruminal parakeratosis in a mature dairy cow: a case report

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    A mature dairy cow was transitioned from a high forage (100% forage) to a high-grain (79% grain) diet over seven days. Continuous ruminal pH recordings were utilized to diagnose the severity of ruminal acidosis. Additionally, blood and rumen papillae biopsies were collected to describe the structural and functional adaptations of the rumen epithelium. On the final day of the grain challenge, the daily mean ruminal pH was 5.41 ± 0.09 with a minimum of 4.89 and a maximum of 6.31. Ruminal pH was under 5.0 for 130 minutes (2.17 hours) which is characterized as the acute form of ruminal acidosis in cattle. The grain challenge increased blood beta-hydroxybutyrate by 1.8 times and rumen papillae mRNA expression of 3-hydroxy-3-methylglutaryl-coenzyme A synthase by 1.6 times. Ultrastructural and histological adaptations of the rumen epithelium were imaged by scanning electron and light microscopy. Rumen papillae from the high grain diet displayed extensive sloughing of the stratum corneum and compromised cell adhesion as large gaps were apparent between cells throughout the strata. This case report represents a rare documentation of how the rumen epithelium alters its function and structure during the initial stage of acute acidosis

    Automated NMR relaxation dispersion data analysis using NESSY

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    <p>Abstract</p> <p>Background</p> <p>Proteins are dynamic molecules with motions ranging from picoseconds to longer than seconds. Many protein functions, however, appear to occur on the micro to millisecond timescale and therefore there has been intense research of the importance of these motions in catalysis and molecular interactions. Nuclear Magnetic Resonance (NMR) relaxation dispersion experiments are used to measure motion of discrete nuclei within the micro to millisecond timescale. Information about conformational/chemical exchange, populations of exchanging states and chemical shift differences are extracted from these experiments. To ensure these parameters are correctly extracted, accurate and careful analysis of these experiments is necessary.</p> <p>Results</p> <p>The software introduced in this article is designed for the automatic analysis of relaxation dispersion data and the extraction of the parameters mentioned above. It is written in Python for multi platform use and highest performance. Experimental data can be fitted to different models using the Levenberg-Marquardt minimization algorithm and different statistical tests can be used to select the best model. To demonstrate the functionality of this program, synthetic data as well as NMR data were analyzed. Analysis of these data including the generation of plots and color coded structures can be performed with minimal user intervention and using standard procedures that are included in the program.</p> <p>Conclusions</p> <p>NESSY is easy to use open source software to analyze NMR relaxation data. The robustness and standard procedures are demonstrated in this article.</p

    UK Lung Cancer RCT Pilot Screening Trial: baseline findings from the screening arm provide evidence for the potential implementation of lung cancer screening.

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    BACKGROUND: Lung cancer screening using low-dose CT (LDCT) was shown to reduce lung cancer mortality by 20% in the National Lung Screening Trial. METHODS: The pilot UK Lung Cancer Screening (UKLS) is a randomised controlled trial of LDCT screening for lung cancer versus usual care. A population-based questionnaire was used to identify high-risk individuals. CT screen-detected nodules were managed by a pre-specified protocol. Cost effectiveness was modelled with reference to the National Lung Cancer Screening Trial mortality reduction. RESULTS: 247 354 individuals aged 50-75 years were approached; 30.7% expressed an interest, 8729 (11.5%) were eligible and 4055 were randomised, 2028 into the CT arm (1994 underwent a CT). Forty-two participants (2.1%) had confirmed lung cancer, 34 (1.7%) at baseline and 8 (0.4%) at the 12-month scan. 28/42 (66.7%) had stage I disease, 36/42 (85.7%) had stage I or II disease. 35/42 (83.3%) had surgical resection. 536 subjects had nodules greater than 50 mm(3) or 5 mm diameter and 41/536 were found to have lung cancer. One further cancer was detected by follow-up of nodules between 15 and 50 mm(3) at 12 months. The baseline estimate for the incremental cost-effectiveness ratio of once-only CT screening, under the UKLS protocol, was £8466 per quality adjusted life year gained (CI £5542 to £12 569). CONCLUSIONS: The UKLS pilot trial demonstrated that it is possible to detect lung cancer at an early stage and deliver potentially curative treatment in over 80% of cases. Health economic analysis suggests that the intervention would be cost effective-this needs to be confirmed using data on observed lung cancer mortality reduction. TRIAL REGISTRATION: ISRCTN 78513845

    A Quantitative Analytical Method to Test for Salt Effects on Giant Unilamellar Vesicles

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    Today, free-standing membranes, i.e. liposomes and vesicles, are used in a multitude of applications, e.g. as drug delivery devices and artificial cell models. Because current laboratory techniques do not allow handling of large sample sizes, systematic and quantitative studies on the impact of different effectors, e.g. electrolytes, are limited. In this work, we evaluated the Hofmeister effects of ten alkali metal halides on giant unilamellar vesicles made of palmitoyloleoylphosphatidylcholine for a large sample size by combining the highly parallel water-in-oil emulsion transfer vesicle preparation method with automatic haemocytometry. We found that this new quantitative screening method is highly reliable and consistent with previously reported results. Thus, this method may provide a significant methodological advance in analysis of effects on free-standing model membranes

    Informing evaluation of a smartphone application for people with acquired brain injury: a stakeholder engagement study

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    Background Brain in Hand is a smartphone application (app) that allows users to create structured diaries with problems and solutions, attach reminders, record task completion and has a symptom monitoring system. Brain in Hand was designed to support people with psychological problems, and encourage behaviour monitoring and change. The aim of this paper is to describe the process of exploring the barriers and enablers for the uptake and use of Brain in Hand in clinical practice, identify potential adaptations of the app for use with people with acquired brain injury (ABI), and determine whether the behaviour change wheel can be used as a model for engagement. Methods We identified stakeholders: ABI survivors and carers, National Health Service and private healthcare professionals, and engaged with them via focus groups, conference presentations, small group discussions, and through questionnaires. The results were evaluated using the behaviour change wheel and descriptive statistics of questionnaire responses. Results We engaged with 20 ABI survivors, 5 carers, 25 professionals, 41 questionnaires were completed by stakeholders. Comments made during group discussions were supported by questionnaire results. Enablers included smartphone competency (capability), personalisation of app (opportunity), and identifying perceived need (motivation). Barriers included a physical and cognitive inability to use smartphone (capability), potential cost and reliability of technology (opportunity), and no desire to use technology or change from existing strategies (motivation). The stakeholders identified potential uses and changes to the app, which were not easily mapped onto the behaviour change wheel, e.g. monitoring fatigue levels, method of logging task completion, and editing the diary on their smartphone. Conclusions The study identified that both ABI survivors and therapists could see a use for Brain in Hand, but wanted users to be able to personalise it themselves to address individual user needs, e.g. monitoring activity levels. The behaviour change wheel is a useful tool when designing and evaluating engagement activities as it addresses most aspects of implementation, however additional categories may be needed to explore the specific features of assistive technology interventions, e.g. technical functions

    Lung cancer mortality reduction by LDCT screening: UKLS randomised trial results and international meta-analysis.

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    Background: The NLST reported a significant 20% reduction in lung cancer mortality with three annual low-dose CT (LDCT) screens and the Dutch-Belgian NELSON trial indicates a similar reduction. We present the results of the UKLS trial. Methods: From October 2011 to February 2013, we randomly allocated 4 055 participants to either a single invitation to screening with LDCT or to no screening (usual care). Eligible participants (aged 50-75) had a risk score (LLPv2) ≥ 4.5% of developing lung cancer over five years. Data were collected on lung cancer cases to 31 December 2019 and deaths to 29 February 2020 through linkage to national registries. The primary outcome was mortality due to lung cancer. We included our results in a random-effects meta-analysis to provide a synthesis of the latest randomised trial evidence. Findings: 1 987 participants in the intervention and 1 981 in the usual care arms were followed for a median of 7.3 years (IQR 7.1-7.6), 86 cancers were diagnosed in the LDCT arm and 75 in the control arm. 30 lung cancer deaths were reported in the screening arm, 46 in the control arm, (relative rate 0.65 [95% CI 0.41-1.02]; p=0.062). The meta-analysis indicated a significant reduction in lung cancer mortality with a pooled overall relative rate of 0.84 (95% CI 0.76-0.92) from nine eligible trials. Interpretation: The UKLS trial of single LDCT indicates a reduction of lung cancer death of similar magnitude to the NELSON and NLST trials and was included in a meta-analysis of nine randomised trials which provides unequivocal support for lung cancer screening in identified risk groups. Funding: NIHR Health Technology Assessment programme; NIHR Policy Research programme; Roy Castle Lung Cancer Foundation
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