Coronary collateral circulation is an alternative source of blood supply to the myocardium when the original blood flow is not sufficient. The pressure derived collateral flow index (CFI) calculated with (P w - P v)/(P a - P v) can be measured during angioplasty and predicts the outcome of the patients with ischemic heart disease. However, the necessity of occluding the coronary artery at maximum hyperemia hampers the wide spread use. We mathematically derived a new equation which calculates CFI in sequential stenoses. The present study aimed to validate the equation in an in vitro model of coronary circulation. The predicted CFI is calculated from the following equation: CFI = (FFRpre - FFRpost(1 - ∆FFR))/(FFRpre + ∆FFR - FFRpost). FFRpre/post is the FFR before and after the angioplasty. ∆FFR is the FFR gradient across the target stenosis. The experimental system consisted of a pump, systemic circulation, coronary circulation, and 5 constrictors placed in the coronary artery. A total of 30 different sequential coronary stenoses were randomly created and 30 different pressure data were obtained. The predicted CFI was compared with the true CFI. A close positive correlation (r = 0.90, p < 0.0001) was found between the predicted CFI and the true CFI. The accuracy of the equation was demonstrated in an in vitro model of coronary circulation.
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Heart Vessels
December 2024
Department of Biomedical Engineering, Veterans Affairs Medical Center, University of Cincinnati, Rhodes Hall 593, 2851 Woodside Drive, Cincinnati, OH, 45219, USA.
Ejection fraction is commonly used to assess Duchenne muscular dystrophy-associated cardiomyopathy (DMDAC), but it may remain normal (wrongly) despite significant myocardial dysfunction in patients. Therefore, better indicators of myocardial dysfunction are needed for longitudinal (with time) assessment and treatment of DMDAC patients. This study evaluates non-invasive LV PV loop-derived elastance, contractility and efficiency in relation to EF for patients developing DMDAC.
View Article and Find Full Text PDFAdv Sci (Weinh)
December 2024
Department of General Surgery, Shanghai Key Laboratory of Gastric Neoplasms, Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
Poor response to 5-fluorouracil (5-FU) remains an obstacle in the treatment of gastric cancer (GC). Super enhancers (SEs) are crucial for determining tumor cell survival under drug pressure. SE landscapes related to 5-FU-resistance are mapped to GC using chromatin immunoprecipitation-sequencing (ChIP-Seq).
View Article and Find Full Text PDFJ Racial Ethn Health Disparities
December 2024
Department of Biostatistics and Epidemiology, College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
Background: The Charlson Comorbidity Index (CCI) is a frequently used mortality predictor based on a scoring system for the number and type of patient comorbidities health researchers have used since the late 1980s. The initial purpose of the CCI was to classify comorbid conditions, which could alter the risk of patient mortality within a 1-year time frame. However, the CCI may not accurately reflect risk among American Indians because they are a small proportion of the US population and possibly lack representation in the original patient cohort.
View Article and Find Full Text PDFSci Rep
December 2024
China Construction Eighth Engineering Division Rail Transit Construction Co., Ltd, Nanjing, 210018, Jiangsu, China.
The existing calculation method for the surrounding rock pressure of shallow buried bias tunnel fails to account for the impact of the progressive failure characteristics of the surrounding rock and slope creep, thereby neglecting the additional pressure arising from slope creep. Therefore, the progressive instability failure mode of the surrounding rock of shallow buried bias tunnel was obtained by numerical simulation. Based on this, the theoretical analysis model of the additional pressure of shallow buried bias tunnel was established, and the calculation formula of the additional pressure was derived.
View Article and Find Full Text PDFInorg Chem
December 2024
Textile Pollution Controlling Engineering Center of Ministry of Ecology and Environment, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China.
Carbon capture and storage (CCS) from dilute sources is an important strategy for stabilizing the concentration of atmospheric carbon dioxide and global temperature. However, the adsorption process is extremely challenging due to the sluggish diffusion rate of dilute CO. Herein, -phthalic acid (PTA)-derived hierarchical porous activated carbon (PTA-C) with abundant micro- and mesopores was successfully prepared for dilute CO (2 vol %) capture at ambient conditions.
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