CoronARe: A Coronary Artery Reconstruction Challenge

CoronARe ranks state-of-the-art methods in symbolic and tomographic coronary artery reconstruction from interventional C-arm rotational angiography. Specifically, we benchmark the performance of the methods using accurately pre-processed data, and study the effects of imperfect pre-processing conditions (segmentation and background subtraction errors). In this first iteration of the challenge, evaluation is performed in a controlled environment using digital phantom images, where accurate 3D ground truth is known

Group-wise similarity registration of point sets using Student’s t-mixture model for statistical shape models

A probabilistic group-wise similarity registration technique based on Student’s t-mixture model (TMM) and a multi-resolution extension of the same (mr-TMM) are proposed in this study, to robustly align shapes and establish valid correspondences, for the purpose of training statistical shape models (SSMs). Shape analysis across large cohorts requires automatic generation of the requisite training sets. Automated segmentation and landmarking of medical images often result in shapes with varying proportions of outliers and consequently require a robust method of alignment and correspondence estimation. Both TMM and mrTMM are validated by comparison with state-of-the-art registration algorithms based on Gaussian mixture models (GMMs), using both synthetic and clinical data. Four clinical data sets are used for validation: (a) 2D femoral heads ( 1000 samples generated from DXA images of healthy subjects); (b) control-hippocampi ( 50 samples generated from T1-weighted magnetic resonance (MR) images of healthy subjects); (c) MCI-hippocampi ( 28 samples generated from MR images of patients diagnosed with mild cognitive impairment); and (d) heart shapes comprising left and right ventricular endocardium and epicardium ( 30 samples generated from short-axis MR images of: 10 healthy subjects, 10 patients diagnosed with pulmonary hypertension and 10 diagnosed with hypertrophic cardiomyopathy). The proposed methods significantly outperformed the state-of-the-art in terms of registration accuracy in the experiments involving synthetic data, with mrTMM offering significant improvement over TMM. With the clinical data, both methods performed comparably to the state-of-the-art for the hippocampi and heart data sets, which contained few outliers. They outperformed the state-of-the-art for the femur data set, containing large proportions of outliers, in terms of alignment accuracy, and the quality of SSMs trained, quantified in terms of generalization, compactness and specificity

Development of a chemogenetic approach to manipulate intracellular pH

Chemogenetic Operation of iNTRacellular prOton Levels(pH-Control)is a novel substrate-based enzymatic method that enables precise spatiotemporalcontrol of ultralocal acidification in cultured cell lines and primaryneurons. The genetically encoded biosensor SypHer3s showed that pH-Controleffectively acidifies cytosolic, mitochondrial, and nuclear pH exclusivelyin the presence of beta-chloro-d-alanine in living cellsin a concentration-dependent manner. The pH-Control approach is promisingfor investigating the ultralocal pH imbalance associated with manydiseases.CE254SWXHI ; NN254SWPZX ; CP254SWT2

15-Lipoxygenase-1 re-expression in colorectal cancer alters endothelial cell features through enhanced expression of TSP-1 and ICAM-1

15-lipoxygenase-1 (15-LOX-1) oxygenates linoleic acid to 13(S)-hydroxyoctadecadienoic acid (HODE). The enzyme is widely suppressed in different cancers and its re-expression has tumor suppressive effects. 15-LOX-1 has been shown to inhibit neoangiogenesis in colorectal cancer (CRC); in the present study we confirm this phenomenon and describe the mechanistic basis. We show that re-expression of 15-LOX-1 in CRC cell lines resulted in decreased transcriptional activity of HIF1α and reduced the expression and secretion of VEGF in both normoxic and hypoxic conditions. Conditioned medium (CM) was obtained from CRC or prostate cancer cell lines re-expressing 15-LOX-1 (15-LOX-1CM). 15-LOX-1CM treated aortic rings from 6-week old C57BL/6 mice showed significantly less vessel sprouting and more organized structure of vascular network. Human umbilical vein endothelial cells (HUVECs) incubated with 15-LOX-1CM showed reduced motility, enhanced expression of intercellular cell adhesion molecule (ICAM-1) and reduced tube formation but no change in proliferation or cell-cycle distribution. HUVECs incubated with 13(S)-HODE partially phenocopied the effects of 15-LOX-1CM, i.e., showed reduced motility and enhanced expression of ICAM-1, but did not reduce tube formation, implying the importance of additional factors. Therefore, a Proteome Profiler Angiogenesis Array was carried out, which showed that Thrombospondin-1 (TSP-1), a matrix glycoprotein known to strongly inhibit neovascularization, was expressed significantly more in HUVECs incubated with 15-LOX-1CM. TSP-1 blockage in HUVECs reduced the expression of ICAM-1 and enhanced cell motility, thereby providing a mechanism for reduced angiogenesis. The anti-angiogenic effects of 15-LOX-1 through enhanced expressions of ICAM-1 and TSP-1 are novel findings and should be explored further to develop therapeutic options. © 201

Three-dimensional reconstruction and NURBS-based structured meshing of coronary arteries from the conventional X-ray angiography projection images

Despite its two-dimensional nature, X-ray angiography (XRA) has served as the gold standard imaging technique in the interventional cardiology for over five decades. Accordingly, demands for tools that could increase efficiency of the XRA procedure for the quantitative analysis of coronary arteries (CA) are constantly increasing. The aim of this study was to propose a novel procedure for three-dimensional modeling of CA from uncalibrated XRA projections. A comprehensive mathematical model of the image formation was developed and used with a robust genetic algorithm optimizer to determine the calibration parameters across XRA views. The frames correspondences between XRA acquisitions were found using a partial-matching approach. Using the same matching method, an efficient procedure for vessel centerline reconstruction was developed. Finally, the problem of meshing complex CA trees was simplified to independent reconstruction and meshing of connected branches using the proposed nonuniform rational B-spline (NURBS)-based method. Because it enables structured quadrilateral and hexahedral meshing, our method is suitable for the subsequent computational modelling of CA physiology (i.e. coronary blood flow, fractional flow reverse, virtual stenting and plaque progression). Extensive validations using digital, physical, and clinical datasets showed competitive performances and potential for further application on a wider scale

How are trainees in clinical microbiology and infectious diseases supervised in Europe? An international cross-sectional questionnaire survey by the Trainee Association of ESCMID

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Circulating Biomarkers of Fibrosis Formation in Patients with Arrhythmogenic Cardiomyopathy

Arrhythmogenic cardiomyopathy (ACM) is a progressive inheritable disease which is characterized by a gradual fibro-(fatty) replacement of the myocardium. Visualization of diffuse and patchy fibrosis patterns is challenging using clinically applied cardiac imaging modalities (e.g., late gadolinium enhancement, LGE). During collagen synthesis and breakdown, carboxy-peptides are released into the bloodstream, specifically procollagen type-I carboxy-terminal propeptides (PICP) and collagen type-I carboxy-terminal telopeptides (ICTP). We collected the serum and EDTA blood samples and clinical data of 45 ACM patients (age 50.11 ± 15.53 years, 44% female), divided into 35 diagnosed ACM patients with a 2010 ARVC Task Force Criteria score (TFC) ≥ 4, and 10 preclinical variant carriers with a TFC < 4. PICP levels were measured using an enzyme-linked immune sorbent assay and ICTP levels with a radio immunoassay. Increased PICP/ICTP ratios suggest a higher collagen deposition. We found significantly higher PICP and PICP/ICTP levels in diagnosed patients compared to preclinical variant carriers (p < 0.036 and p < 0.027). A moderate negative correlation existed between right ventricular ejection fractions (RVEF) and the PICP/ICTP ratio (r = -0.46, p = 0.06). In addition, significant correlations with left ventricular function (LVEF r = -0.53, p = 0.03 and end-systolic volume r = 0.63, p = 0.02) were found. These findings indicate impaired contractile performance due to pro-fibrotic remodeling. Follow-up studies including a larger number of patients should be performed to substantiate our findings and the validity of those levels as potential promising biomarkers in ACM

Salt loading in canola oil fed SHRSP rats induces endothelial dysfunction

This study aimed to determine if 50 days of canola oil intake in the absence or presence of salt loading affects: (1) antioxidant and oxidative stress markers, (2) aortic mRNA of NADPH oxidase (NOX) subunits and superoxide dismutase (SOD) isoforms and (3) endothelial function in SHRSP rats. SHRSP rats were fed a diet containing 10 wt/wt% soybean oil or 10 wt/wt% canola oil, and given tap water or water containing 1% NaCl for 50 days. Without salt, canola oil significantly increased RBC SOD, plasma cholesterol and triglycerides, aortic p22phox, NOX2 and CuZn-SOD mRNA, and decreased RBC glutathione peroxidase activity. With salt, canola oil reduced RBC SOD and catalase activity, LDL-C, and p22phox mRNA compared with canola oil alone, whereas plasma malondialdehyde (MDA) was reduced and RBC MDA and LDL-C were higher. With salt, the canola oil group had significantly reduced endothelium-dependent vasodilating responses to ACh and contractile responses to norepinephrine compared with the canola oil group without salt and to the WKY rats. These results indicate that ingestion of canola oil increases O2 - generation, and that canola oil ingestion in combination with salt leads to endothelial dysfunction in the SHRSP model

Digging out the debate: Types of corrective feedback and their effects on grammatical accuracy in writing

The effect of written corrective feedback (WCF) has been a highly controversial issue in second language acquisition and writing research and various views have been put forward. Therefore, in order to support findings in the literature, this study aims to focus on the possible effects of various feedback types and revision process on EFL learners’ writing performance by replicating the study of Shintani, Ellis and Suzuki (2014). The participants of the study are 146 EFL learners who study at the School of Foreign Languages at a state university in Turkey and have A2 level language proficiency according to CEFR descriptions. As the design of the study, the participants were divided into five feedback groups; namely direct corrective feedback (DCF), metalinguistic explanation (ME), direct corrective feedback and revision (DCF+R), metalinguistic explanation and revision (ME+R) and a control group. Following a treatment session consisting of three writing tasks including direct and indirect corrective feedback, the learners’ performances were evaluated in terms of their accuracy in the use of past simple tense and indefinite articles in each task and they were interviewed considering their views about the effects of each feedback type. The findings suggest that there is no statistically significant difference in the effect of types of direct corrective feedback or revision process on grammatical accuracy in writing whereas indirect corrective feedback seems effective and learners preferred it for their written products. © The Turkish Online Journal of Educational Technology