368 research outputs found

    Effect of Varying Prior Information in Axillary 2D Microwave Tomography

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    We numerically assess the potential of microwave tomography (MWT) for the detection and dielectric properties estimation of axillary lymph nodes (ALNs), and we study the robustness of our system using prior information with varying levels of accuracy. We adopt a 2-dimensional MWT system with 8 antennas (0.5-2.5 GHz) placed around the axillary region. The reconstruction algorithm implements the distorted Born iterative method. We show that: (i) when accurate prior knowledge of the axillary tissues (fat and muscle) is available, our system successfully detects an ALN; (ii) ±30% error in the prior estimation of fat and muscle dielectric properties does not affect image quality; (iii) ±7mm error in muscle position causes slight artifacts, while ± 14mm error in muscle position affects ALN detection. To the best of our knowledge, this is the first paper in the literature to study the impact of prior information accuracy on detecting an ALN using MWT.info:eu-repo/semantics/publishedVersio

    Consistency of parental and self-reported adolescent wellbeing : evidence from developmental language disorder

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    Research on adolescent wellbeing in Developmental Language Disorder (DLD) has previously been examined through measures of parent (proxy) or self-reported wellbeing, but never has a study included both and enabled comparison between the two. The current study reports parent and self rated wellbeing of adolescents with DLD and Low Language (LL) ability, as well as their typically developing (TD) peers. It also examines consistency between raters and factors influencing correspondence. Adolescents aged 10–11 with DLD (n = 30), LL (n = 29) or TD (n = 48) were recruited from eight UK primary schools. A battery of standardized language, psychosocial and wellbeing assessments, including the KIDSCREEN-27 were administered. Adolescent ratings of wellbeing were similar across groups on three of the five wellbeing dimensions, but those with DLD had lower self-reported Autonomy and Parental Relations than their TD peers, and both the DLD and LL group had lower School Environment scores than their TD peers. By parental report, the DLD and LL group were considered to have lower wellbeing on all five wellbeing dimensions relative to their TD peers. Paired sample t-test analyses indicated a high level of variance between parent and adolescent reported wellbeing for multiple wellbeing domains, especially Psychological Wellbeing. Importantly, predictors of the level of agreement between parent and adolescent reported psychological wellbeing differed between groups: cognitive reappraisal and sociability predicted this level of agreement for adolescents with LL, while social competence predicted agreement in DLD and TD. This study emphasizes the necessity of allowing adolescents of all language abilities to report their own wellbeing, as their perspective does not align with that of their parents. It also highlights the importance of including the full spectrum of need when investigating the impact of language ability on consistency between proxy and self-reported wellbeing

    Single cell RNA sequencing and lineage tracing confirm mesenchyme to epithelial transformation (MET) contributes to repair of the endometrium at menstruation

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    The human endometrium experiences repetitive cycles of tissue wounding characterised by piecemeal shedding of the surface epithelium and rapid restoration of tissue homeostasis. In this study, we used a mouse model of endometrial repair and three transgenic lines of mice to investigate whether epithelial cells that become incorporated into the newly formed luminal epithelium have their origins in one or more of the mesenchymal cell types present in the stromal compartment of the endometrium. Using scRNAseq, we identified a novel population of PDGFRb + mesenchymal stromal cells that developed a unique transcriptomic signature in response to endometrial breakdown/repair. These cells expressed genes usually considered specific to epithelial cells and in silico trajectory analysis suggested they were stromal fibroblasts in transition to becoming epithelial cells. To confirm our hypothesis we used a lineage tracing strategy to compare the fate of stromal fibroblasts (PDGFRa+) and stromal perivascular cells (NG2/CSPG4+). We demonstrated that stromal fibroblasts can undergo a mesenchyme to epithelial transformation and become incorporated into the re-epithelialised luminal surface of the repaired tissue. This study is the first to discover a novel population of wound-responsive, plastic endometrial stromal fibroblasts that contribute to the rapid restoration of an intact luminal epithelium during endometrial repair. These findings form a platform for comparisons both to endometrial pathologies which involve a fibrotic response (Asherman’s syndrome, endometriosis) as well as other mucosal tissues which have a variable response to wounding

    Could Reducing Body Fatness Reduce the Risk of Aggressive Prostate Cancer via the Insulin Signalling Pathway? A Systematic Review of the Mechanistic Pathway

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    Excess body weight is thought to increase the risk of aggressive prostate cancer (PCa), although the biological mechanism is currently unclear. Body fatness is positively associated with a diminished cellular response to insulin and biomarkers of insulin signalling have been positively associated with PCa risk. We carried out a two-pronged systematic review of (a) the effect of reducing body fatness on insulin biomarker levels and (b) the effect of insulin biomarkers on PCa risk, to determine whether a reduction in body fatness could reduce PCa risk via effects on the insulin signalling pathway. We identified seven eligible randomised controlled trials of interventions designed to reduce body fatness which measured insulin biomarkers as an outcome, and six eligible prospective observational studies of insulin biomarkers and PCa risk. We found some evidence that a reduction in body fatness improved insulin sensitivity although our confidence in this evidence was low based on GRADE (Grading of Recommendations, Assessment, Development and Evaluations). We were unable to reach any conclusions on the effect of insulin sensitivity on PCa risk from the few studies included in our systematic review. A reduction in body fatness may reduce PCa risk via insulin signalling, but more high-quality evidence is needed before any conclusions can be reached regarding PCa

    Single-cell RNA sequencing redefines the mesenchymal cell landscape of mouse endometrium

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    The endometrium is a dynamic tissue that exhibits remarkable resilience to repeated episodes of differentiation, breakdown, regeneration, and remodeling. Endometrial physiology relies on a complex interplay between the stromal and epithelial compartments with the former containing a mixture of fibroblasts, vascular, and immune cells. There is evidence for rare populations of putative mesenchymal progenitor cells located in the perivascular niche of human endometrium, but the existence of an equivalent cell population in mouse is unclear. We used the Pdgfrb‐BAC‐eGFP transgenic reporter mouse in combination with bulk and single‐cell RNA sequencing to redefine the endometrial mesenchyme. In contrast to previous reports we show that CD146 is expressed in both PDGFRβ + perivascular cells and CD31 + endothelial cells. Bulk RNAseq revealed cells in the perivascular niche which express the high levels of Pdgfrb as well as genes previously identified in pericytes and/or vascular smooth muscle cells (Acta2, Myh11, Olfr78, Cspg4, Rgs4, Rgs5, Kcnj8, and Abcc9). scRNA‐seq identified five subpopulations of cells including closely related pericytes/vascular smooth muscle cells and three subpopulations of fibroblasts. All three fibroblast populations were PDGFRα+/CD34 + but were distinct in their expression of Ngfr/Spon2/Angptl7 (F1), Cxcl14/Smoc2/Rgs2 (F2), and Clec3b/Col14a1/Mmp3 (F3), with potential functions in the regulation of immune responses, response to wounding, and organization of extracellular matrix, respectively. Immunohistochemistry was used to investigate the spatial distribution of these populations revealing F1/NGFR + cells in most abundance beside epithelial cells. We provide the first definitive analysis of mesenchymal cells in the adult mouse endometrium identifying five subpopulations providing a platform for comparisons between mesenchymal cells in endometrium and other adult tissues which are prone to fibrosis

    SMS for Life: a pilot project to improve anti-malarial drug supply management in rural Tanzania using standard technology

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    Background: Maintaining adequate supplies of anti-malarial medicines at the health facility level in rural sub-Saharan Africa is a major barrier to effective management of the disease. Lack of visibility of anti-malarial stock levels at the health facility level is an important contributor to this problem. Methods: A 21-week pilot study, 'SMS for Life', was undertaken during 2009-2010 in three districts of rural Tanzania, involving 129 health facilities. Undertaken through a collaborative partnership of public and private institutions, SMS for Life used mobile telephones, SMS messages and electronic mapping technology to facilitate provision of comprehensive and accurate stock counts from all health facilities to each district management team on a weekly basis. The system covered stocks of the four different dosage packs of artemether-lumefantrine (AL) and quinine injectable. Results: Stock count data was provided in 95% of cases, on average. A high response rate (≥ 93%) was maintained throughout the pilot. The error rate for composition of SMS responses averaged 7.5% throughout the study; almost all errors were corrected and messages re-sent. Data accuracy, based on surveillance visits to health facilities, was 94%. District stock reports were accessed on average once a day. The proportion of health facilities with no stock of one or more anti-malarial medicine (i.e. any of the four dosages of AL or quinine injectable) fell from 78% at week 1 to 26% at week 21. In Lindi Rural district, stock-outs were eliminated by week 8 with virtually no stock-outs thereafter. During the study, AL stocks increased by 64% and quinine stock increased 36% across the three districts. Conclusions: The SMS for Life pilot provided visibility of anti-malarial stock levels to support more efficient stock management using simple and widely available SMS technology, via a public-private partnership model that worked highly effectively. The SMS for Life system has the potential to alleviate restricted availability of anti-malarial drugs or other medicines in rural or under-resourced areas

    ERS/EAACI statement on adherence to international adult asthma guidelines

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    Clinical practice guidelines based on the best available evidence, aim to standardize and optimize asthma diagnosis and management. Nevertheless, there are concerns that particularly between different groups of healthcare professionals (HCPs), adherence to guidelines is suboptimal. Further to these concerns, the aims of this ERS/EAACI Statement were (1) via an international online survey, to evaluate and compare the understanding of and adherence to international asthma guidelines by HCPs of different specialties, (2) via systematic reviews of the literature, to assess effectiveness of strategies focused at improving implementation of guideline-recommended interventions, and compare process and clinical outcomes in patients managed by Specialists (respiratory physicians or allergists) or Generalists (internists or general practitioners). The online survey identified discrepancies between HCPs of different specialties which may be due to poor dissemination or lack of knowledge of the guidelines but also a reflection of the adaptations HCPs working in different clinical settings make, based on their resources. The systematic reviews demonstrated that multifaceted quality improvement initiatives addressing multiple challenges to guidelines adherence, or the input from additional specialized HCPs are most effective in improving guidelines adherence. More data are needed to evaluate differences in process and clinical outcomes among patients managed by Generalists or Specialists. Our results reveal a need for guidelines to consider the heterogeneity of real-life settings for asthma management and tailor their recommendations accordingly. Continuous, multifaceted quality improvement processes are required to optimize and maintain guidelines adherence. Validated referral pathways for uncontrolled asthma or for uncertain diagnosis are needed

    Assessment of learning curves in complex surgical interventions: a consecutive case-series study

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    Background: Surgical interventions are complex, which complicates their rigorous assessment through randomised clinical trials. An important component of complexity relates to surgeon experience and the rate at which the required level of skill is achieved, known as the learning curve. There is considerable evidence that operator performance for surgical innovations will change with increasing experience. Such learning effects complicate evaluations; the start of the trial might be delayed, resulting in loss of surgeon equipoise or, if an assessment is undertaken before performance has stabilised, the true impact of the intervention may be distorted. Methods: Formal estimation of learning parameters is necessary to characterise the learning curve, model its evolution and adjust for its presence during assessment. Current methods are either descriptive or model the learning curve through three main features: the initial skill level, the learning rate and the final skill level achieved. We introduce a fourth characterising feature, the duration of the learning period, which provides an estimate of the point at which learning has stabilised. We propose a two-phase model to estimate formally all four learning curve features. Results: We demonstrate that the two-phase model can be used to estimate the end of the learning period by incorporating a parameter for estimating the duration of learning. This is achieved by breaking down the model into a phase describing the learning period and one describing cases after the final skill level is reached, with the break point representing the length of learning. We illustrate the method using cardiac surgery data. Conclusions: This modelling extension is useful as it provides a measure of the potential cost of learning an intervention and enables statisticians to accommodate cases undertaken during the learning phase and assess the intervention after the optimal skill level is reached. The limitations of the method and implications for the optimal timing of a definitive randomised controlled trial are also discussed

    HER2 and TOP2A in high-risk early breast cancer patients treated with adjuvant epirubicin-based dose-dense sequential chemotherapy

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    <p>Abstract</p> <p>Background</p> <p>HER2 and TOP2A parameters (gene status, mRNA and protein expression) have individually been associated with the outcome of patients treated with anthracyclines. The aim of this study was to comprehensively evaluate the prognostic/predictive significance of the above parameters in early, high-risk breast cancer patients treated with epirubicin-based, dose-dense sequential adjuvant chemotherapy.</p> <p>Methods</p> <p>In a series of 352 breast carcinoma tissues from patients that had been post-operatively treated with epirubicin-CMF with or without paclitaxel, we assessed HER2 and TOP2A gene status (chromogenic in situ hybridization), mRNA expression (quantitative reverse transcription PCR), as well as HER2 and TopoIIa protein expression (immunohistochemistry).</p> <p>Results</p> <p>HER2 and TOP2A amplification did not share the same effects on their downstream molecules, with consistent patterns observed in HER2 mRNA and protein expression according to HER2 amplification (all parameters strongly inter-related, p values < 0.001), but inconsistent patterns in the case of TOP2A. TOP2A gene amplification (7% of all cases) was not related to TOP2A mRNA and TopoIIa protein expression, while TOP2A mRNA and TopoIIa protein were strongly related to each other (p < 0.001). Hence, TOP2A amplified tumors did not correspond to tumors with high TOP2A mRNA or TopoIIa protein expression, while the latter were characterized by high Ki67 scores (p = 0.003 and p < 0.001, respectively). Multivariate analysis adjusted for nodal involvement, hormone receptor status, Ki67 score and HER2/TOP2A parameters revealed HER2/TOP2A co-amplification (21.2% of HER2 amplified tumors) as an independent favorable prognostic factor for DFS (HR = 0.13, 95% CI: 0.02-0.96, p = 0.046); in contrast, increased HER2/TOP2A mRNA co-expression was identified as an independent adverse prognostic factor for both DFS (HR = 2.41, 95% CI: 1.31-4.42, p = 0.005) and OS (HR = 2.83, 95% CI: 1.42-5.63, p = 0.003), while high TOP2A mRNA expression was an independent adverse prognostic factor for OS (HR = 2.06, 95% CI: 1.23-3.46, p = 0.006). None of the parameters tested was associated with response to paclitaxel.</p> <p>Conclusions</p> <p>This study confirms the favorable prognostic value of HER2/TOP2A co-amplification and the adverse prognostic value of high TOP2A mRNA expression extending it to the adjuvant treatment setting in early high-risk breast cancer. The strong adverse prognostic impact of high HER2/TOP2A mRNA co-expression needs further validation in studies designed to evaluate markers predictive for anthracyclines.</p> <p>Trial registration</p> <p>Australian New Zealand Clinical Trials Registry <a href="http://www.anzctr.org.au/ACTRN12611000506998">ACTRN12611000506998</a>.</p
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