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BACKGROUND: Treatment with systemic corticosteroids in patients with acute exacerbations of chronic obstructive pulmonary disease (COPD) is associated with debilitating adverse effects. Therefore, strategies to reduce systemic corticosteroid exposure are urgently required and might be offered by a personalised biomarker-guided approach to treatment. The aim of this study was to determine whether an algorithm based on blood eosinophil counts could safely reduce systemic corticosteroid exposure in patients admitted to hospital with acute exacerbations of COPD. METHODS: We did a multicentre, randomised, controlled, open-label, non-inferiority trial at the respiratory departments of three different university-affiliated hospitals in Denmark. Eligible participants were patients included within 24h of admission to the participating sites, aged at least 40 years, with known airflow limitation (defined as a post-bronchodilator FEV1/forced vital capacity [FVC] ratio ≤0·70) and a specialist-verified diagnosis of COPD, who were designated to start on systemic corticosteroids by the respiratory medicine physician on duty. We randomly assigned patients (1:1) to either eosinophil-guided therapy or standard therapy with systemic corticosteroids. Both investigators and patients were aware of the group assignment. All patients received 80 mg of intravenous methylprednisolone on the first day. The eosinophil-guided group were from the second day given 37·5 mg of prednisolone oral tablet daily (for a maximum of up to 4 days) on days when their blood eosinophil count was at least 0·3 × 109 cells per L. On days when the eosinophil count was lower, prednisolone was not administered. If a patient was discharged during the treatment period, a treatment based on the last measured eosinophil count was prescribed for the remaining days within the 5-day period (last observation carried forward). The control group received 37·5 mg of prednisolone tablets daily from the second day for 4 days. The primary outcome was the number of days alive and out of hospital within 14 days after recruitment, assessed by intention to treat (ITT). Secondary outcomes included treatment failure at day 30 (ie, recurrence of acute exacerbation of COPD resulting in emergency room visits, admission to hospital, or need to intensify pharmacological treatment), number of deaths on day 30, and duration of treatment with systemic corticosteroids. The non-inferiority margin was 1·2 days (SD 3·8). This trial is registered at ClinicalTrials.gov, number NCT02857842, and was completed in January, 2019. FINDINGS: Between Aug 3, 2016, and Sept 30, 2018, 159 patients in the eosinophil-guided group and 159 patients in the control group were included in the ITT analyses. There was no between-group difference for days alive and out of hospital within 14 days after recruitment: mean 8·9 days (95% CI 8·3-9·6) in the eosinophil-guided group versus 9·3 days (8·7-9·9) in the control group (absolute difference -0·4, 95% CI -1·3 to 0·5; p=0·34). Treatment failure at 30 days occurred in 42 (26%) of 159 patients in the eosinophil-guided group and 41 (26%) of 159 in the control group (difference 0·6%, 95% CI -9·0 to 10·3; p=0·90). At 30 days nine patients (6%) of 159 in the eosinophil-guided group and six (4%) of 159 in the control group had died (difference 1·9%, 95% CI -2·8 to 6·5; p=0·43). Median duration of systemic corticosteroid therapy was lower in the eosinophil-guided group: 2 days (IQR 1·0 to 3·0) compared with 5 days (5·0 to 5·0) in the control group, p<0·0001. INTERPRETATION: Eosinophil-guided therapy was non-inferior compared with standard care for the number of days alive and out of hospital, and reduced the duration of systemic corticosteroid exposure, although we could not entirely exclude harm on some secondary outcome measures. Larger studies will help to determine the full safety profile of this strategy and its role in the management of COPD exacerbations. FUNDING: The Danish Regions Medical Fund and the Danish Council for Independent Research.
Asunto(s)
Eosinófilos/efectos de los fármacos , Glucocorticoides/uso terapéutico , Metilprednisolona/uso terapéutico , Prednisolona/uso terapéutico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Administración Oral , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Dinamarca , Femenino , Humanos , Masculino , Resultado del TratamientoRESUMEN
BACKGROUND: Computational models of myocardial ischemia often use oversimplified ischemic source representations to simulate epicardial potentials. The purpose of this study was to explore the influence of biophysically justified, subject-specific ischemic zone representations on epicardial potentials. METHODS: We developed and implemented an image-based simulation pipeline, using intramural recordings from a canine experimental model to define subject-specific ischemic regions within the heart. Static epicardial potential distributions, reflective of ST segment deviations, were simulated and validated against measured epicardial recordings. RESULTS: Simulated epicardial potential distributions showed strong statistical correlation and visual agreement with measured epicardial potentials. Additionally, we identified and described in what way border zone parameters influence epicardial potential distributions during the ST segment. CONCLUSION: From image-based simulations of myocardial ischemia, we generated subject-specific ischemic sources that accurately replicated epicardial potential distributions. Such models are essential in understanding the underlying mechanisms of the bioelectric fields that arise during ischemia and are the basis for more sophisticated simulations of body surface ECGs.
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Electrocardiografía , Modelos Cardiovasculares , Isquemia Miocárdica/fisiopatología , Enfermedad Aguda , Animales , Simulación por Computador , Modelos Animales de Enfermedad , PerrosRESUMEN
Heart failure (HF) is a major cause of morbidity and mortality worldwide. The global burden of HF continues to rise, with prevalence rates estimated at 1-2% and incidence approaching 5-10 per 1000 persons annually. The complex pathophysiology of HF impacts virtually all aspects of normal cardiac function - from structure and mechanics to metabolism and electrophysiology - leading to impaired mechanical contraction and sudden cardiac death. Pharmacotherapy and device therapy are the primary methods of treating HF, but neither is able to stop or reverse disease progression. Thus, there is an acute need to translate basic research into improved HF therapy. Animal model investigations are a critical component of HF research. However, the translation from cellular and animal models to the bedside is hampered by significant differences between species and among physiological scales. Our studies over the last 8 years show that hypotheses generated in animal models need to be validated in human in vitro models. Importantly, however, human heart investigations can establish translational platforms for safety and efficacy studies before embarking on costly and risky clinical trials. This review summarizes recent developments in human HF investigations of electrophysiology remodelling, metabolic remodelling, and ß-adrenergic remodelling and discusses promising new technologies for HF research.
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Insuficiencia Cardíaca/fisiopatología , Corazón/fisiopatología , Animales , Arritmias Cardíacas/fisiopatología , Corazón/fisiología , HumanosRESUMEN
Electrocardiographic (ECG) ST segment shifts are often used as markers for detecting myocardial ischemia. Literature suggests that the progression of ischemia, occurs from the endocardium and spreads towards the epicardium, eventually becoming transmural. Our study with animal models has found the progression of ischemia, characterized by ST elevations to be more complex and heterogeneous in its distribution. We used in situ canine preparations, wherein the animals were subjected to demand ischemia by reducing coronary flow and raising the heart rate through atrial pacing. At reduced flow, increasing the heart rate caused pockets of ST elevations to appear variously distributed in the sub-epicardial, midmyocardial and endocardial regions. Further reduction in coronary flow with simultaneous raising of the heart rate, increased the extent and magnitude of ST elevated regions, that in certain cases became transmural.
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Morphogenesis, initiation of differentiation marker gene expression, and their correlation with CCAT/enhancer binding protein (C/EBP) expression were analyzed in the developing fetal rat small intestine. Expressions of mRNAs for lactase-phlorizin hydrolase (LPH), intestinal alkaline phosphatase (IALP), carbamoyl-phosphate synthetase (CPS), and three isoforms of C/EBP were simultaneously determined by Northern blot analysis from 15 to 19 days of gestation. At 17 days of gestation, prior to villus formation as demonstrated by light and electron microscopy, only CPS and C/EBPalpha, -beta, and -delta expression could clearly be detected. Both LPH and IALP mRNA were definitely detectable in proximal and middle intestine on day 18, as soon as the stratified epithelium of the early intestine had been transformed into a single layer of columnar epithelium lining villi. This distribution was confirmed by in situ hybridization for LPH mRNA. During the period of transformation when the columnar epithelium and villi were forming, no LPH or IALP mRNA was detectable in the immature distal one-third of the fetal intestine. Preceding villus morphogenesis, immunostaining demonstrated nuclear localization of C/EBPalpha protein in intestinal epithelial cells, with continued expression in all enterocytes through 19 days of gestation. Enhanced expression of C/EBPalpha mRNA and protein began 24 h prior to the initiation of the differentiation markers, suggesting that it may play a role in regulation of fetal intestinal differentiation.
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Proteínas de Unión al ADN/metabolismo , Intestino Delgado/embriología , Proteínas Nucleares/metabolismo , Fosfatasa Alcalina/genética , Animales , Biomarcadores , Proteínas Potenciadoras de Unión a CCAAT , Carbamoil-Fosfato Sintasa (Glutamina-Hidrolizante)/genética , Diferenciación Celular , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Edad Gestacional , Intestino Delgado/citología , Intestino Delgado/metabolismo , Lactasa-Florizina Hidrolasa/genética , ARN Mensajero/genética , Ratas , Ratas Sprague-DawleyRESUMEN
This study was aimed at measuring the changes in the hyoid bone position, tongue position, and hypopharyngeal airway space in subjects with mandibular setback osteotomies. Lateral cephalometric radiographs of 15 patients were taken preoperatively, 6 weeks postoperatively, and at the follow-up with a mean of 1.5 +/- 0.4 years. A significant decrease in the hypopharyngeal airway space following mandibular setback surgery was found (P < .01). This change sustained during the follow-up period. The hyoid bone moved down (P < .001), and the lower tongue point also moved down (P < .05) postoperatively. Results of the study suggest that narrowing of the hypopharyngeal airway space due to the posterior and inferior movement of the tongue can be permanent.