233 research outputs found

    Image based Wheel Detection using Random Forest Classification

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    The aim of this master thesis is to detect and recognise wheels in images by means of image analysis. This could later on serve as a foundation for a safer vehicle counting and classification method than those currently in use that requires personnel to cross the lanes on installation. The general layout of the classification system consists of five stages: multi-scale transformation, window extractor, pre-processing, classification and cluster analysis. In order to obtain the training and testing data for evaluation and construction of the system, images that illustrate moving cars on a road are acquired. From these, several positive and negative windows are extracted that visualizes wheels and non-wheels. For the classification stage, the learning algorithm used is Random Forest. Moreover, with the Random Forest as the foundation, two different concepts were introduced to further improve the predictions. These are referred to as bootstrap configuration and cascading classification. The results are evaluated be means of Receiver Operating Characteristics and contingency tables. In this master thesis, the final system produces a satisfying result based on the false positive rate and true positive rate. For future development, the amount of examples in the training data could be increased in order to gain more knowledge in the teaching of the classifier. Furthermore, an optimization of the program could lead to faster execution time, which is a requirement if this system is to operate in real-time. To conclude, the system produces a satisfying result for wheel detection that can be used as a foundation when constructing a general system for vehicle counting and classification

    Shrunken Pore Syndrome Is Frequently Occurring in Severe COVID-19

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    Funding Information: The study was funded by the SciLifeLab/Knut and Alice Wallenberg national COVID-19 research program (M.H.: KAW 2020.0182, KAW 2020.0241), the Swedish Heart-Lung Foundation (M.H.: 20210089, 20190639, 20190637), the Swedish Research Council (R.F.: 2014-02569, 2014-07606), The Swedish Kidney Foundation (R.F.: F2020-0054), and The Swedish Society of Medicine (M.H. SLS-938101). Funding bodies had no role in the design of the study, data collection, interpretation, or in the writing of the manuscript. Publisher Copyright: © 2022 by the authors.A selective decrease in the renal filtration of larger molecules is attributed to the shrinkage of glomerular pores, a condition termed Shrunken Pore Syndrome (SPS). SPS is associated with poor long-term prognosis. We studied SPS as a risk marker in a cohort of patients with COVID-19 treated in an intensive care unit. SPS was defined as a ratio < 0.7 when the estimated glomerular filtration rate (eGFR), determined by cystatin C, calculated by the Cystatin C Caucasian-Asian-Pediatric-Adult equation (CAPA), was divided by the eGFR determined by creatinine, calculated by the revised Lund–Malmö creatinine equation (LMR). Clinical data were prospectively collected. In total, SPS was present in 86 (24%) of 352 patients with COVID-19 on ICU admission. Patients with SPS had a higher BMI, Simplified Physiology Score (SAPS3), and had diabetes and/or hypertension more frequently than patients without SPS. Ninety-nine patients in the total cohort were women, 50 of whom had SPS. In dexamethasone-naĂŻve patients, C-reactive protein (CRP), TNF-alpha, and interleukin-6 did not differ between SPS and non-SPS patients. Demographic factors (gender, BMI) and illness severity (SAPS3) were independent predictors of SPS. Age and dexamethasone treatment did not affect the frequency of SPS after adjustments for age, sex, BMI, and acute severity. SPS is frequent in severely ill COVID-19 patients. Female gender was associated with a higher proportion of SPS. Demographic factors and illness severity were independent predictors of SPS.publishersversionpublishe

    Estimated glomerular filtration rates are higher when creatinine-based equations are compared with a cystatin C-based equation in coronavirus disease 2019

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    Funding Information: The study was funded by the SciLifeLab/Knut and Alice Wallenberg national COVID‐19 research program (Michael Hultström; KAW 2020.0182, KAW 2020.0241), the Swedish Heart‐Lung Foundation (Michael Hultström; 20210089, 20190639, 20190637), the Swedish Research Council (Robert Frithiof; 2014‐02569, 2014‐07606), The Swedish Kidney Foundation (Robert Frithiof; F2020‐0054), and The Swedish Society of Medicine (Michael Hultström; SLS‐938101). Funding bodies had no role in the design of the study, data collection, interpretation, or in the writing of the article. Funding Information: Medicinska ForskningsrĂ„det; SciLifeLab/Knut and Alice Wallenberg National COVID‐19 Research Program, Grant/Award Numbers: KAW 2020.0182, KAW 2020.0241; Swedish Heart‐Lung Foundation, Grant/Award Numbers: 20210089, 20190639, 20190637; Swedish Kidney Foundation, Grant/Award Number: F2020‐0054; Swedish Society of Medicine, Grant/Award Number: SLS‐938101; the Swedish Research Council, Grant/Award Numbers: 2014‐07606, 2014‐02569 Funding information Publisher Copyright: © 2022 The Authors. Acta Anaesthesiologica Scandinavica published by John Wiley & Sons Ltd on behalf of Acta Anaesthesiologica Scandinavica Foundation.Objectives: Estimations of glomerular filtration rate (eGFR) are based on analyses of creatinine and cystatin C, respectively. Coronavirus disease 2019 (COVID-19) patients in the intensive care unit (ICU) often have acute kidney injury (AKI) and are at increased risk of drug-induced kidney injury. The aim of this study was to compare creatinine-based eGFR equations to cystatin C-based eGFR in ICU patients with COVID-19. Methods: After informed consent, we included 370 adult ICU patients with COVID-19. Creatinine and cystatin C were analyzed at admission to the ICU as part of the routine care. Creatinine-based eGFR (ml/min) was calculated using the following equations, developed in chronological order; the Cockcroft–Gault (C-G), Modified Diet in Renal Disease (MDRD)1999, MDRD 2006, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), and Lund–Malmö revised (LMR) equations, which were compared with eGFR calculated using the cystatin C-based Caucasian Asian Pediatric Adult (CAPA) equation. Results: The median eGFR when determined by C-G was 99 ml/min and interquartile range (IQR: 67 ml/min). Corresponding estimations for MDRD1999 were 90 ml/min (IQR: 54); MDRD2006: 85 ml/min (IQR: 51); CKD-EPI: 91 ml/min (IQR: 47); and for LMR 83 ml/min (IQR: 41). eGFR was calculated using cystatin C and the CAPA equation value was 70 ml/min (IQR: 38). All differences between creatinine-based eGFR versus cystatin C-based eGFR were significant (p <.00001). Conclusions: Estimation of GFR based on various analyses of creatinine are higher when compared with a cystatin C-based equation. The C-G equation had the worst performance and should not be used in combination with modern creatinine analysis methods for determination of drug dosage in COVID-19 patients.publishersversionepub_ahead_of_prin

    Critical illness polyneuropathy, myopathy and neuronal biomarkers in COVID-19 patients: A prospective study

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    OBJECTIVE: The aim was to characterize the electrophysiological features and plasma biomarkers of critical illness polyneuropathy (CIN) and myopathy (CIM) in coronavirus disease 2019 (COVID-19) patients with intensive care unit acquired weakness (ICUAW). METHODS: An observational ICU cohort study including adult patients admitted to the ICU at Uppsala University Hospital, Uppsala, Sweden, from March 13th to June 8th 2020. We compared the clinical, electrophysiological and plasma biomarker data between COVID-19 patients who developed CIN/CIM and those who did not. Electrophysiological characteristics were also compared between COVID-19 and non-COVID-19 ICU patients. RESULTS: 111 COVID-19 patients were included, 11 of whom developed CIN/CIM. Patients with CIN/CIM had more severe illness; longer ICU stay, more thromboembolic events and were more frequently treated with invasive ventilation for longer than 2 weeks. In particular CIN was more frequent among COVID-19 patients with ICUAW (50%) compared with a non-COVID-19 cohort (0%, p = 0.008). Neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAp) levels were higher in the CIN/CIM group compared with those that did not develop CIN/CIM (both p = 0.001) and correlated with nerve amplitudes. CONCLUSIONS: CIN/CIM was more prevalent among COVID-19 ICU patients with severe illness. SIGNIFICANCE: COVID-19 patients who later developed CIN/CIM had significantly higher NfL and GFAp in the early phase of ICU care, suggesting their potential as predictive biomarkers for CIN/CIM

    The extent of neuroradiological findings in COVID-19 shows correlation with blood biomarkers, Glasgow coma scale score and days in intensive care

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    Background and purpose: A wide range of neuroradiological findings has been reported in patients with coronavirus disease 2019 (COVID-19), ranging from subcortical white matter changes to infarcts, haemorrhages and focal contrast media enhancement. These have been descriptively but inconsistently reported and correlations with clinical findings and biomarkers have been difficult to extract from the literature. The purpose of this study was to quantify the extents of neuroradiological findings in a cohort of patients with COVID-19 and neurological symptoms, and to investigate correlations with clinical findings, duration of intensive care and biomarkers in blood. Material and methods: Patients with positive SARS-CoV-2 and at least one new-onset neurological symptom were included from April until July 2020. Nineteen patients were examined regarding clinical symptoms, biomarkers in blood and MRI of the brain. In order to quantify the MRI findings, a semi-quantitative neuroradiological severity scale was constructed a priori, and applied to the MR images by two specialists in neuroradiology. Results and conclusions: The score from the severity scale correlated significantly with blood biomarkers of CNS injury (glial fibrillary acidic protein, total-tau, ubiquitin carboxyl-terminal hydrolase L1) and inflammation (C-reactive protein), Glasgow Coma Scale score, and the number of days spent in intensive care. The underlying radiological assessments had inter-rater agreements of 90.5%/86% (for assessments with 2/3 alternatives). Total intraclass correlation was 0.80. Previously reported neuroradiological findings in COVID-19 have been diverse and heterogenous. In this study, the extent of findings in MRI examination of the brain, quantified using a structured report, shows correlation with relevant biomarkers

    Osthole Ameliorates Renal Fibrosis in Mice by Suppressing Fibroblast Activation and Epithelial-Mesenchymal Transition

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    Renal fibrosis is a common pathway of virtually all progressive kidney diseases. Osthole (OST, 7-Methoxy-8-(3-methylbut-2-enyl)-2-chromenone), a derivative of coumarin mainly found in plants of the Apiaceae family, has shown inhibitory effects on inflammation, oxidative stress, fibrosis and tumor progression. The present study investigated whether OST mediates its effect via suppressing fibroblast activation and epithelial-mesenchymal transition (EMT) in unilateral ureteral obstruction (UUO)-induced renal fibrosis in mice. Herein, we found that OST inhibited fibroblast activation in a dose-dependent manner by inhibiting the transforming growth factor-ÎČ1 (TGFÎČ1)-Smad pathway. OST also blocked fibroblast proliferation by reducing DNA synthesis and downregulating the expressions of proliferation- and cell cycle-related proteins including proliferating cell nuclear antigen (PCNA), CyclinD1 and p21 Waf1/Cip1. Meanwhile, in the murine model of renal interstitial fibrosis induced by UUO, myofibroblast activation with increased expression of α-smooth muscle actin (α-SMA) and proliferation were attenuated by OST treatment. Additionally, we provided in vivo evidence suggesting that OST repressed EMT with preserved E-cadherin and reduced Vimentin expression in obstructed kidney. UUO injury-induced upregulation of EMT-related transcription factors, Snail family transcriptional repressor-1(Snail 1) and Twist family basic helix-loop-helix (BHLH) transcription factor (Twist) as well as elevated G2/M arrest of tubular epithelial cell, were rescued by OST treatment. Further, OST treatment reversed aberrant expression of TGFÎČ1-Smad signaling pathway, increased level of proinflammatory cytokines and NF-kappaB (NF-ÎșB) activation in kidneys with obstructive nephropathy. Taken together, these findings suggest that OST hinder renal fibrosis in UUO mouse mainly through inhibition of fibroblast activation and EMT

    Markers of NETosis and DAMPs are altered in critically ill COVID-19 patients

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    Background Coronavirus disease 19 (COVID-19) is known to present with disease severities of varying degree. In its most severe form, infection may lead to respiratory failure and multi-organ dysfunction. Here we study the levels of extracellular histone H3 (H3), neutrophil elastase (NE) and cfDNA in relation to other plasma parameters, including the immune modulators GAS6 and AXL, ICU scoring systems and mortality in patients with severe COVID-19. Methods We measured plasma H3, NE, cfDNA, GAS6 and AXL concentration in plasma of 83 COVID-19-positive and 11 COVID-19-negative patients at admission to the Intensive Care Unit (ICU) at the Uppsala University hospital, a tertiary hospital in Sweden and a total of 333 samples obtained from these patients during the ICU-stay. We determined their correlation with disease severity, organ failure, mortality and other blood parameters. Results H3, NE, cfDNA, GAS6 and AXL were increased in plasma of COVID-19 patients compared to controls. cfDNA and GAS6 decreased in time in in patients surviving to 30 days post ICU admission. Plasma H3 was a common feature of COVID-19 patients, detected in 40% of the patients at ICU admission. Although these measures were not predictive of the final outcome of the disease, they correlated well with parameters of tissue damage (H3 and cfDNA) and neutrophil counts (NE). A subset of samples displayed H3 processing, possibly due to proteolysis. Conclusions Elevated H3 and cfDNA levels in COVID-19 patients illustrate the severity of the cellular damage observed in critically ill COVID-19 patients. The increase in NE indicates the important role of neutrophil response and the process of NETosis in the disease. GAS6 appears as part of an early activated mechanism of response in Covid-19.The study was supported through grants from the dedSciLifeLab/KAW national COVID-19 research program project grant (MH), by Scilifelab, the Knut and Alice Wallenberg Foundation and in part by the Swedish Research Council (RF, grant no 2014-02569 and 2014-07606), and the Netherlands Thrombosis Foundation (GN).N
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