81 results on '"Shu-Xia Li"'
Search Results
2. Hypertension Trends and Disparities Over 12 Years in a Large Health System: Leveraging the Electronic Health Records
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John E. Brush, Yuan Lu, Yuntian Liu, Jordan R. Asher, Shu‐Xia Li, Mitsuaki Sawano, Patrick Young, Wade L. Schulz, Mark Anderson, John S. Burrows, and Harlan M. Krumholz
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health systems ,hypertension prevalence ,racial disparities ,real‐world data ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background The digital transformation of medical data enables health systems to leverage real‐world data from electronic health records to gain actionable insights for improving hypertension care. Methods and Results We performed a serial cross‐sectional analysis of outpatients of a large regional health system from 2010 to 2021. Hypertension was defined by systolic blood pressure ≥140 mm Hg, diastolic blood pressure ≥90 mm Hg, or recorded treatment with antihypertension medications. We evaluated 4 methods of using blood pressure measurements in the electronic health record to define hypertension. The primary outcomes were age‐adjusted prevalence rates and age‐adjusted control rates. Hypertension prevalence varied depending on the definition used, ranging from 36.5% to 50.9% initially and increasing over time by ≈5%, regardless of the definition used. Control rates ranged from 61.2% to 71.3% initially, increased during 2018 to 2019, and decreased during 2020 to 2021. The proportion of patients with a hypertension diagnosis ranged from 45.5% to 60.2% initially and improved during the study period. Non‐Hispanic Black patients represented 25% of our regional population and consistently had higher prevalence rates, higher mean systolic and diastolic blood pressure, and lower control rates compared with other racial and ethnic groups. Conclusions In a large regional health system, we leveraged the electronic health record to provide real‐world insights. The findings largely reflected national trends but showed distinctive regional demographics and findings, with prevalence increasing, one‐quarter of the patients not controlled, and marked disparities. This approach could be emulated by regional health systems seeking to improve hypertension care.
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- 2024
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3. Pre-COVID-19 hospital quality and hospital response to COVID-19: examining associations between risk-adjusted mortality for patients hospitalised with COVID-19 and pre-COVID-19 hospital quality
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Michelle Schreiber, Jing Zhang, Yongfei Wang, Zhenqiu Lin, Arjun K Venkatesh, Lee A Fleisher, Elizabeth W Triche, Lisa G Suter, Doris Peter, Shu-Xia Li, Jacqueline Grady, Kerry McDowell, Erica Norton, and Susannah Bernheim
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Medicine - Abstract
Objectives The extent to which care quality influenced outcomes for patients hospitalised with COVID-19 is unknown. Our objective was to determine if prepandemic hospital quality is associated with mortality among Medicare patients hospitalised with COVID-19.Design This is a retrospective observational study. We calculated hospital-level risk-standardised in-hospital and 30-day mortality rates (risk-standardised mortality rates, RSMRs) for patients hospitalised with COVID-19, and correlation coefficients between RSMRs and pre-COVID-19 hospital quality, overall and stratified by hospital characteristics.Setting Short-term acute care hospitals and critical access hospitals in the USA.Participants Hospitalised Medicare beneficiaries (Fee-For-Service and Medicare Advantage) age 65 and older hospitalised with COVID-19, discharged between 1 April 2020 and 30 September 2021.Intervention/exposure Pre-COVID-19 hospital quality.Outcomes Risk-standardised COVID-19 in-hospital and 30-day mortality rates (RSMRs).Results In-hospital (n=4256) RSMRs for Medicare patients hospitalised with COVID-19 (April 2020–September 2021) ranged from 4.5% to 59.9% (median 18.2%; IQR 14.7%–23.7%); 30-day RSMRs ranged from 12.9% to 56.2% (IQR 24.6%–30.6%). COVID-19 RSMRs were negatively correlated with star rating summary scores (in-hospital correlation coefficient −0.41, p
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- 2024
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4. Ethnic and racial differences in self-reported symptoms, health status, activity level, and missed work at 3 and 6 months following SARS-CoV-2 infection
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Kelli N. O’Laughlin, Robin E. Klabbers, Imtiaz Ebna Mannan, Nicole L. Gentile, Rachel E. Geyer, Zihan Zheng, Huihui Yu, Shu-Xia Li, Kwun C. G. Chan, Erica S. Spatz, Ralph C. Wang, Michelle L’Hommedieu, Robert A. Weinstein, Ian D. Plumb, Michael Gottlieb, Ryan M. Huebinger, Melissa Hagen, Joann G. Elmore, Mandy J. Hill, Morgan Kelly, Samuel McDonald, Kristin L. Rising, Robert M. Rodriguez, Arjun Venkatesh, Ahamed H. Idris, Michelle Santangelo, Katherine Koo, Sharon Saydah, Graham Nichol, Kari A. Stephens, and the INSPIRE Group
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COVID-19 ,disparities ,cohort ,race ,ethnicity ,SARS-CoV-2 ,Public aspects of medicine ,RA1-1270 - Abstract
IntroductionData on ethnic and racial differences in symptoms and health-related impacts following SARS-CoV-2 infection are limited. We aimed to estimate the ethnic and racial differences in symptoms and health-related impacts 3 and 6 months after the first SARS-CoV-2 infection.MethodsParticipants included adults with SARS-CoV-2 infection enrolled in a prospective multicenter US study between 12/11/2020 and 7/4/2022 as the primary cohort of interest, as well as a SARS-CoV-2-negative cohort to account for non-SARS-CoV-2-infection impacts, who completed enrollment and 3-month surveys (N = 3,161; 2,402 SARS-CoV-2-positive, 759 SARS-CoV-2-negative). Marginal odds ratios were estimated using GEE logistic regression for individual symptoms, health status, activity level, and missed work 3 and 6 months after COVID-19 illness, comparing each ethnicity or race to the referent group (non-Hispanic or white), adjusting for demographic factors, social determinants of health, substance use, pre-existing health conditions, SARS-CoV-2 infection status, COVID-19 vaccination status, and survey time point, with interactions between ethnicity or race and time point, ethnicity or race and SARS-CoV-2 infection status, and SARS-CoV-2 infection status and time point.ResultsFollowing SARS-CoV-2 infection, the majority of symptoms were similar over time between ethnic and racial groups. At 3 months, Hispanic participants were more likely than non-Hispanic participants to report fair/poor health (OR: 1.94; 95%CI: 1.36–2.78) and reduced activity (somewhat less, OR: 1.47; 95%CI: 1.06–2.02; much less, OR: 2.23; 95%CI: 1.38–3.61). At 6 months, differences by ethnicity were not present. At 3 months, Other/Multiple race participants were more likely than white participants to report fair/poor health (OR: 1.90; 95% CI: 1.25–2.88), reduced activity (somewhat less, OR: 1.72; 95%CI: 1.21–2.46; much less, OR: 2.08; 95%CI: 1.18–3.65). At 6 months, Asian participants were more likely than white participants to report fair/poor health (OR: 1.88; 95%CI: 1.13–3.12); Black participants reported more missed work (OR, 2.83; 95%CI: 1.60–5.00); and Other/Multiple race participants reported more fair/poor health (OR: 1.83; 95%CI: 1.10–3.05), reduced activity (somewhat less, OR: 1.60; 95%CI: 1.02–2.51; much less, OR: 2.49; 95%CI: 1.40–4.44), and more missed work (OR: 2.25; 95%CI: 1.27–3.98).DiscussionAwareness of ethnic and racial differences in outcomes following SARS-CoV-2 infection may inform clinical and public health efforts to advance health equity in long-term outcomes.
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- 2024
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5. The association between platelet glycoprotein-specific antibodies and response to short-term high-dose dexamethasone with prednisone maintenance treatment in adult patients with primary immune thrombocytopenia
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Yan-Qiu Hou, Yan Wang, Chang-Xun Liu, Shu-Xia Li, Ya-Lan Peng, Wang Dong-Dong, and Ru-La Sa
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primary immune thrombocytopenia ,platelet glycoprotein-specific autoantibody ,treatment response ,dexamethasone ,prednisone ,Medicine - Abstract
Objective The aim of the present study was to detect the association between platelet glycoprotein-specific autoantibodies and the patient response to short-term high-dose dexamethasone (HD-DXM) + prednisone maintenance treatment. Methods The data from 112 adult patients newly diagnosed with ITP who were administered first-line HD-DXM + prednisone maintenance therapy between January 2016 and January 2021 were retrospectively analyzed. Results A total of 72 patients positive for platelet glycoprotein-specific antibodies were enrolled in the antibody-positive group, and 40 patients not positive for platelet glycoprotein-specific antibodies were enrolled in the antibody-negative group. In the antibody-positive group, six platelet glycoprotein-specific antibody types were found: 41.67% of the patients were anti-GP IIb/IIIa-positive only, 5.56% were anti-GP Ib/IX-positive only, 5.56% were anti-P-selectin-positive only, 19.44% were anti-GP IIb/IIIa- and anti-GP Ib/IX-positive, 16.67% were anti-GP Ib/IX- and P-selectin-positive and 11.11% were positive for all three antibodies. There was no significant difference in the overall response rate between the antibody-positive group and the antibody-negative group (94.44 versus 80.00%, p = .221). However, the CR rate was significantly higher in the antibody-positive group than in the antibody-negative group (69.44% versus 40.00%, p = .032). The logistic regression analysis revealed that platelet glycoprotein-specific antibody positivity and age were two factors that could affect patient response. Conclusions The present study discovered that adult patients newly diagnosed with ITP who had positive platelet glycoprotein-specific antibody test results were likely to achieve a better response after treatment with HD-DXM + prednisone maintenance.
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- 2022
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6. A novel long non-coding RNA, DIR, increases drought tolerance in cassava by modifying stress-related gene expression
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Shi-man DONG, Liang XIAO, Zhi-bo LI, Jie SHEN, Hua-bing YAN, Shu-xia LI, Wen-bin LIAO, and Ming PENG
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lncRNA ,RNA-seq ,drought stress ,cassava ,DIR ,Agriculture (General) ,S1-972 - Abstract
Cassava is an important tropical cash crop. Severe drought stresses affect cassava productivity and quality, and cause great economic losses in agricultural production. Enhancing the drought tolerance of cassava can effectively improve its yield. Long non-coding RNAs (lncRNAs) are present in a wide variety of eukaryotes. Recently, increasing evidence has shown that lncRNAs play a critical role in the responses to abiotic stresses. However, the function of cassava lncRNAs in the drought response remains largely unknown. In this study, we identified a novel lncRNA, DROUGHT-INDUCED INTERGENIC lncRNA (DIR). Gene expression analysis showed that DIR was significantly induced by drought stress treatment, but did not respond to abscisic acid (ABA) or jasmonic acid (JA) treatments. In addition, overexpression of the DIR gene enhanced proline accumulation and drought tolerance in transgenic cassava. RNA-seq analysis revealed that DIR preferentially affected drought-related genes that were linked to transcription and metabolism. Moreover, RNA pull-down mass spectrometry analysis showed that DIR interacted with 325 proteins. A protein–protein interaction (PPI) analysis found a marked enrichment in proteins associated with the mRNA export and protein quality control pathways. Collectively, these results suggest that DIR and its interacting proteins that regulate mRNA or protein metabolism are involved in mediating the drought stress response. Thus, regulating DIR expression has potential for improving cassava yield under drought conditions.
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- 2022
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7. Timely estimation of National Admission, readmission, and observation-stay rates in medicare patients with acute myocardial infarction, heart failure, or pneumonia using near real-time claims data
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Shu-Xia Li, Yongfei Wang, Sonam D. Lama, Jennifer Schwartz, Jeph Herrin, Hao Mei, Zhenqiu Lin, Susannah M. Bernheim, Steven Spivack, Harlan M. Krumholz, and Lisa G. Suter
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Real-time reporting ,Prediction models ,Medicare claims data ,Readmission ,Observation stay ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background To estimate, prior to finalization of claims, the national monthly numbers of admissions and rates of 30-day readmissions and post-discharge observation-stays for Medicare fee-for-service beneficiaries hospitalized with acute myocardial infarction (AMI), heart failure (HF), or pneumonia. Methods The centers for Medicare & Medicaid Services (CMS) Integrated Data Repository, including the Medicare beneficiary enrollment database, was accessed in June 2015, February 2017, and February 2018. We evaluated patterns of delay in Medicare claims accrual, and used incomplete, non-final claims data to develop and validate models for real-time estimation of admissions, readmissions, and observation stays. Results These real-time reporting models accurately estimate, within 2 months from admission, the monthly numbers of admissions, 30-day readmission and observation-stay rates for patients with AMI, HF, or pneumonia. Conclusions This work will allow CMS to track the impact of policy decisions in real time and enable hospitals to better monitor their performance nationally.
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- 2020
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8. Association of in-hospital resource utilization with post-acute spending in Medicare beneficiaries hospitalized for acute myocardial infarction: a cross-sectional study
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Sudhakar V. Nuti, Shu-Xia Li, Xiao Xu, Lesli S. Ott, Tara Lagu, Nihar R. Desai, Karthik Murugiah, Michael Duan, John Martin, Nancy Kim, and Harlan M. Krumholz
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Medicare ,Costs ,Bundled payments ,Post-acute ,Health policy ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Efforts to decrease hospitalization costs could increase post-acute care costs. This effect could undermine initiatives to reduce overall episode costs and have implications for the design of health care under alternative payment models. Methods Among Medicare fee-for-service beneficiaries aged ≥65 years hospitalized with acute myocardial infarction (AMI) between July 2010 and June 2013 in the Premier Healthcare Database, we studied the association of in-hospital and post-acute care resource utilization and outcomes by in-hospital cost tertiles. Results Among patients with AMI at 326 hospitals, the median (range) of each hospital’s mean per-patient in-hospital risk-standardized cost (RSC) for the low, medium, and high cost tertiles were $16,257 ($13,097–$17,648), $18,544 ($17,663–$19,875), and $21,831 ($19,923–$31,296), respectively. There was no difference in the median (IQR) of risk-standardized post-acute payments across cost-tertiles: $5014 (4295-6051), $4980 (4349-5931) and $4922 (4056-5457) for the low (n = 90), medium (n = 98), and high (n = 86) in-hospital RSC tertiles (p = 0.21), respectively. In-hospital and 30-day mortality rates did not differ significantly across the in-hospital RSC tertiles; however, 30-day readmission rates were higher at hospitals with higher in-hospital RSCs: median = 17.5, 17.8, and 18.0% at low, medium, and high in-hospital RSC tertiles, respectively (p = 0.005 for test of trend across tertiles). Conclusions In our study of patients hospitalized with AMI, greater resource utilization during the hospitalization was not associated with meaningful differences in costs or mortality during the post-acute period. These findings suggest that it may be possible for higher cost hospitals to improve efficiency in care without increasing post-acute care utilization or worsening outcomes.
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- 2019
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9. China Patient-centered Evaluative Assessment of Cardiac Events Prospective Study of Acute Myocardial Infarction: Study Design
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Jing Li, Rachel P Dreyer, Xi Li, Xue Du, Nicholas S Downing, Li Li, Hai-Bo Zhang, Fang Feng, Wen-Chi Guan, Xiao Xu, Shu-Xia Li, Zhen-Qiu Lin, Frederick A Masoudi, John A Spertus, Harlan M Krumholz, Li-Xin Jiang, and The China PEACE Collaborative Group
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Acute Myocardial Infarction ,Outcomes Research ,Patient-reported Outcome Measures ,Prospective Cohort ,Medicine - Abstract
Background: Despite the rapid growth in the incidence of acute myocardial infarction (AMI) in China, there is limited information about patients′ experiences after AMI hospitalization, especially on long-term adverse events and patient-reported outcomes (PROs). Methods: The China Patient-centered Evaluative Assessment of Cardiac Events (PEACE)-Prospective AMI Study will enroll 4000 consecutive AMI patients from 53 diverse hospitals across China and follow them longitudinally for 12 months to document their treatment, recovery, and outcomes. Details of patients′ medical history, treatment, and in-hospital outcomes are abstracted from medical charts. Comprehensive baseline interviews are being conducted to characterize patient demographics, risk factors, presentation, and healthcare utilization. As part of these interviews, validated instruments are administered to measure PROs, including quality of life, symptoms, mood, cognition, and sexual activity. Follow-up interviews, measuring PROs, medication adherence, risk factor control, and collecting hospitalization events are conducted at 1, 6, and 12 months after discharge. Supporting documents for potential outcomes are collected for adjudication by clinicians at the National Coordinating Center. Blood and urine samples are also obtained at baseline, 1- and 12-month follow-up. In addition, we are conducting a survey of participating hospitals to characterize their organizational characteristics. Conclusion: The China PEACE-Prospective AMI study will be uniquely positioned to generate new information regarding patient′s experiences and outcomes after AMI in China and serve as a foundation for quality improvement activities.
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- 2016
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10. Enhancing the prediction of acute kidney injury risk after percutaneous coronary intervention using machine learning techniques: A retrospective cohort study.
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Chenxi Huang, Karthik Murugiah, Shiwani Mahajan, Shu-Xia Li, Sanket S Dhruva, Julian S Haimovich, Yongfei Wang, Wade L Schulz, Jeffrey M Testani, Francis P Wilson, Carlos I Mena, Frederick A Masoudi, John S Rumsfeld, John A Spertus, Bobak J Mortazavi, and Harlan M Krumholz
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Medicine - Abstract
BACKGROUND:The current acute kidney injury (AKI) risk prediction model for patients undergoing percutaneous coronary intervention (PCI) from the American College of Cardiology (ACC) National Cardiovascular Data Registry (NCDR) employed regression techniques. This study aimed to evaluate whether models using machine learning techniques could significantly improve AKI risk prediction after PCI. METHODS AND FINDINGS:We used the same cohort and candidate variables used to develop the current NCDR CathPCI Registry AKI model, including 947,091 patients who underwent PCI procedures between June 1, 2009, and June 30, 2011. The mean age of these patients was 64.8 years, and 32.8% were women, with a total of 69,826 (7.4%) AKI events. We replicated the current AKI model as the baseline model and compared it with a series of new models. Temporal validation was performed using data from 970,869 patients undergoing PCIs between July 1, 2016, and March 31, 2017, with a mean age of 65.7 years; 31.9% were women, and 72,954 (7.5%) had AKI events. Each model was derived by implementing one of two strategies for preprocessing candidate variables (preselecting and transforming candidate variables or using all candidate variables in their original forms), one of three variable-selection methods (stepwise backward selection, lasso regularization, or permutation-based selection), and one of two methods to model the relationship between variables and outcome (logistic regression or gradient descent boosting). The cohort was divided into different training (70%) and test (30%) sets using 100 different random splits, and the performance of the models was evaluated internally in the test sets. The best model, according to the internal evaluation, was derived by using all available candidate variables in their original form, permutation-based variable selection, and gradient descent boosting. Compared with the baseline model that uses 11 variables, the best model used 13 variables and achieved a significantly better area under the receiver operating characteristic curve (AUC) of 0.752 (95% confidence interval [CI] 0.749-0.754) versus 0.711 (95% CI 0.708-0.714), a significantly better Brier score of 0.0617 (95% CI 0.0615-0.0618) versus 0.0636 (95% CI 0.0634-0.0638), and a better calibration slope of observed versus predicted rate of 1.008 (95% CI 0.988-1.028) versus 1.036 (95% CI 1.015-1.056). The best model also had a significantly wider predictive range (25.3% versus 21.6%, p < 0.001) and was more accurate in stratifying AKI risk for patients. Evaluated on a more contemporary CathPCI cohort (July 1, 2015-March 31, 2017), the best model consistently achieved significantly better performance than the baseline model in AUC (0.785 versus 0.753), Brier score (0.0610 versus 0.0627), calibration slope (1.003 versus 1.062), and predictive range (29.4% versus 26.2%). The current study does not address implementation for risk calculation at the point of care, and potential challenges include the availability and accessibility of the predictors. CONCLUSIONS:Machine learning techniques and data-driven approaches resulted in improved prediction of AKI risk after PCI. The results support the potential of these techniques for improving risk prediction models and identification of patients who may benefit from risk-mitigation strategies.
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- 2018
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11. Systolic Blood Pressure Response in SPRINT (Systolic Blood Pressure Intervention Trial) and ACCORD (Action to Control Cardiovascular Risk in Diabetes): A Possible Explanation for Discordant Trial Results
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Chenxi Huang, Sanket S. Dhruva, Andreas C. Coppi, Frederick Warner, Shu‐Xia Li, Haiqun Lin, Khurram Nasir, and Harlan M. Krumholz
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ACCORD (Action to Control Cardiovascular Risk in Diabetes) ,outcome ,systolic blood pressure ,SPRINT (Systolic Blood Pressure Intervention Trial) ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
BackgroundSPRINT (Systolic Blood Pressure Intervention Trial) and the ACCORD (Action to Control Cardiovascular Risk in Diabetes) blood pressure trial used similar interventions but produced discordant results. We investigated whether differences in systolic blood pressure (SBP) response contributed to the discordant trial results. Methods and ResultsWe evaluated the distributions of SBP response during the first year for the intensive and standard treatment groups of SPRINT and ACCORD using growth mixture models. We assessed whether significant differences existed between trials in the distributions of SBP achieved at 1 year and the treatment‐independent relationships of achieved SBP with risks of primary outcomes defined in each trial, heart failure, stroke, and all‐cause death. We examined whether visit‐to‐visit variability was associated with heterogeneous treatment effects. Among the included 9027 SPRINT and 4575 ACCORD participants, the difference in mean SBP achieved between treatment groups was 15.7 mm Hg in SPRINT and 14.2 mm Hg in ACCORD, but SPRINT had significantly less between‐group overlap in the achieved SBP (standard deviations of intensive and standard groups, respectively: 6.7 and 5.9 mm Hg in SPRINT versus 8.8 and 8.2 mm Hg in ACCORD; P
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- 2017
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12. Discovery of temporal and disease association patterns in condition-specific hospital utilization rates.
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Julian S Haimovich, Arjun K Venkatesh, Abbas Shojaee, Andreas Coppi, Frederick Warner, Shu-Xia Li, and Harlan M Krumholz
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Medicine ,Science - Abstract
Identifying temporal variation in hospitalization rates may provide insights about disease patterns and thereby inform research, policy, and clinical care. However, the majority of medical conditions have not been studied for their potential seasonal variation. The objective of this study was to apply a data-driven approach to characterize temporal variation in condition-specific hospitalizations. Using a dataset of 34 million inpatient discharges gathered from hospitals in New York State from 2008-2011, we grouped all discharges into 263 clinical conditions based on the principal discharge diagnosis using Clinical Classification Software in order to mitigate the limitation that administrative claims data reflect clinical conditions to varying specificity. After applying Seasonal-Trend Decomposition by LOESS, we estimated the periodicity of the seasonal component using spectral analysis and applied harmonic regression to calculate the amplitude and phase of the condition's seasonal utilization pattern. We also introduced four new indices of temporal variation: mean oscillation width, seasonal coefficient, trend coefficient, and linearity of the trend. Finally, K-means clustering was used to group conditions across these four indices to identify common temporal variation patterns. Of all 263 clinical conditions considered, 164 demonstrated statistically significant seasonality. Notably, we identified conditions for which seasonal variation has not been previously described such as ovarian cancer, tuberculosis, and schizophrenia. Clustering analysis yielded three distinct groups of conditions based on multiple measures of seasonal variation. Our study was limited to New York State and results may not directly apply to other regions with distinct climates and health burden. A substantial proportion of medical conditions, larger than previously described, exhibit seasonal variation in hospital utilization. Moreover, the application of clustering tools yields groups of clinically heterogeneous conditions with similar seasonal phenotypes. Further investigation is necessary to uncover common etiologies underlying these shared seasonal phenotypes.
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- 2017
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13. Identification of Hospital Cardiac Services for Acute Myocardial Infarction Using Individual Patient Discharge Data
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Tiffany E. Chang, Harlan M. Krumholz, Shu‐Xia Li, John Martin, and Isuru Ranasinghe
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cardiovascular disease ,health services research ,myocardial infarction ,population ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background The availability of hospital cardiac services may vary between hospitals and influence care processes and outcomes. However, data on available cardiac services are restricted to a limited number of services collected by the American Hospital Association (AHA) annual survey. We developed an alternative method to identify hospital services using individual patient discharge data for acute myocardial infarction (AMI) in the Premier Healthcare Database. Methods and Results Thirty‐five inpatient cardiac services relevant for AMI care were identified using American Heart Association/American College of Cardiology guidelines. Thirty‐one of these services could be defined using patient‐level administrative data codes, such as International Classification of Diseases, Ninth Revision, Clinical Modification and Current Procedural Terminology codes. A hospital was classified as providing a service if it had ≥5 instances for the service in the Premier database from 2009 to 2011. Using this system, the availability of these services among 432 Premier hospitals ranged from 100% (services such as chest X‐ray) to 1.2% (heart transplant service). To measure the accuracy of this method using administrative data, we calculated agreement between the AHA survey and Premier for a subset of 16 services defined by both sources. There was a high percentage of agreement (≥80%) for 11 of 16 (68.8%) services, moderate agreement for 3 of 16 (18.8%) services, and low agreement (≤50%) for 2 of 16 services (12.5%). Conclusions The availability of cardiac services for AMI care varies widely among hospitals. Using individual patient discharge data is a feasible method to identify these cardiac services, particularly for those services pertaining to inpatient care.
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- 2016
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14. Features Extraction of Flotation Froth Images and BP Neural Network Soft-Sensor Model of Concentrate Grade Optimized by Shuffled Cuckoo Searching Algorithm
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Jie-sheng Wang, Shuang Han, Na-na Shen, and Shu-xia Li
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Technology ,Medicine ,Science - Abstract
For meeting the forecasting target of key technology indicators in the flotation process, a BP neural network soft-sensor model based on features extraction of flotation froth images and optimized by shuffled cuckoo search algorithm is proposed. Based on the digital image processing technique, the color features in HSI color space, the visual features based on the gray level cooccurrence matrix, and the shape characteristics based on the geometric theory of flotation froth images are extracted, respectively, as the input variables of the proposed soft-sensor model. Then the isometric mapping method is used to reduce the input dimension, the network size, and learning time of BP neural network. Finally, a shuffled cuckoo search algorithm is adopted to optimize the BP neural network soft-sensor model. Simulation results show that the model has better generalization results and prediction accuracy.
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- 2014
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15. SOM Neural Network Fault Diagnosis Method of Polymerization Kettle Equipment Optimized by Improved PSO Algorithm
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Jie-sheng Wang, Shu-xia Li, and Jie Gao
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Technology ,Medicine ,Science - Abstract
For meeting the real-time fault diagnosis and the optimization monitoring requirements of the polymerization kettle in the polyvinyl chloride resin (PVC) production process, a fault diagnosis strategy based on the self-organizing map (SOM) neural network is proposed. Firstly, a mapping between the polymerization process data and the fault pattern is established by analyzing the production technology of polymerization kettle equipment. The particle swarm optimization (PSO) algorithm with a new dynamical adjustment method of inertial weights is adopted to optimize the structural parameters of SOM neural network. The fault pattern classification of the polymerization kettle equipment is to realize the nonlinear mapping from symptom set to fault set according to the given symptom set. Finally, the simulation experiments of fault diagnosis are conducted by combining with the industrial on-site historical data of the polymerization kettle and the simulation results show that the proposed PSO-SOM fault diagnosis strategy is effective.
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- 2014
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16. Acute decompensated heart failure is routinely treated as a cardiopulmonary syndrome.
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Kumar Dharmarajan, Kelly M Strait, Tara Lagu, Peter K Lindenauer, Mary E Tinetti, Joanne Lynn, Shu-Xia Li, and Harlan M Krumholz
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Medicine ,Science - Abstract
Heart failure as recognized and treated in typical practice may represent a complex condition that defies discrete categorizations. To illuminate this complexity, we examined treatment strategies for patients hospitalized and treated for decompensated heart failure. We focused on the receipt of medications appropriate for other acute conditions associated with shortness of breath including acute asthma, pneumonia, and exacerbated chronic obstructive pulmonary disease.Using Premier Perspective(®), we studied adults hospitalized with a principal discharge diagnosis of heart failure and evidence of acute heart failure treatment from 2009-2010 at 370 US hospitals. We determined treatment with acute respiratory therapies during the initial 2 days of hospitalization and daily during hospital days 3-5. We also calculated adjusted odds of in-hospital death, admission to the intensive care unit, and late intubation (intubation after hospital day 2). Among 164,494 heart failure hospitalizations, 53% received acute respiratory therapies during the first 2 hospital days: 37% received short-acting inhaled bronchodilators, 33% received antibiotics, and 10% received high-dose corticosteroids. Of these 87,319 hospitalizations, over 60% continued receiving respiratory therapies after hospital day 2. Respiratory treatment was more frequent among the 60,690 hospitalizations with chronic lung disease. Treatment with acute respiratory therapy during the first 2 hospital days was associated with higher adjusted odds of all adverse outcomes.Acute respiratory therapy is administered to more than half of patients hospitalized with and treated for decompensated heart failure. Heart failure is therefore regularly treated as a broader cardiopulmonary syndrome rather than as a singular cardiac condition.
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- 2013
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17. Emergency Department Utilization for Emergency Conditions During COVID-19
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Venkatesh, Arjun K., Janke, Alexander T., Shu-Xia, Li, Rothenberg, Craig, Goyal, Pawan, Terry, Aisha, and Lin, Michelle
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- 2021
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18. Hypertension Trends and Disparities Over 12 Years in a Large Health System: Leveraging the Electronic Health Records.
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Brush Jr, John E., Yuan Lu, Yuntian Liu, Asher, Jordan R., Shu-Xia Li, Mitsuaki Sawano, Young, Patrick, Schulz, Wade L., Anderson, Mark, Burrows, John S., and Krumholz, Harlan M.
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- 2024
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19. Ethnic and racial differences in self-reported symptoms, health status, activity level, and missed work at 3 and 6 months following SARS-CoV-2 infection.
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O'Laughlin, Kelli N., Klabbers, Robin E., Mannan, Imtiaz Ebna, Gentile, Nicole L., Geyer, Rachel E., Zihan Zheng, Huihui Yu, Shu-Xia Li, Chan, Kwun C. G., Spatz, Erica S., Wang, Ralph C., L'Hommedieu, Michelle, Weinstein, Robert A., Plumb, Ian D., Gottlieb, Michael, Huebinger, Ryan M., Hagen, Melissa, Elmore, Joann G., Hill, Mandy J., and Kelly, Morgan
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- 2024
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20. Timely estimation of National Admission, readmission, and observation-stay rates in medicare patients with acute myocardial infarction, heart failure, or pneumonia using near real-time claims data
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Jennifer Schwartz, Yongfei Wang, Shu-Xia Li, Sonam D. Lama, Jeph Herrin, Hao Mei, Harlan M Krumholz, Lisa G. Suter, Zhenqiu Lin, Steven B. Spivack, and Susannah M. Bernheim
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medicine.medical_specialty ,Time Factors ,Myocardial Infarction ,Observation ,Medicare ,Prediction models ,Patient Readmission ,01 natural sciences ,Health informatics ,Health administration ,Insurance Claim Review ,03 medical and health sciences ,Patient Admission ,0302 clinical medicine ,Real-time reporting ,Observation stay ,medicine ,Humans ,030212 general & internal medicine ,Myocardial infarction ,0101 mathematics ,health care economics and organizations ,Aged ,Heart Failure ,Estimation ,business.industry ,Health Policy ,Nursing research ,lcsh:Public aspects of medicine ,010102 general mathematics ,Medicare claims data ,lcsh:RA1-1270 ,Pneumonia ,Length of Stay ,medicine.disease ,United States ,Heart failure ,Emergency medicine ,business ,Medicaid ,Readmission ,Research Article - Abstract
Background To estimate, prior to finalization of claims, the national monthly numbers of admissions and rates of 30-day readmissions and post-discharge observation-stays for Medicare fee-for-service beneficiaries hospitalized with acute myocardial infarction (AMI), heart failure (HF), or pneumonia. Methods The centers for Medicare & Medicaid Services (CMS) Integrated Data Repository, including the Medicare beneficiary enrollment database, was accessed in June 2015, February 2017, and February 2018. We evaluated patterns of delay in Medicare claims accrual, and used incomplete, non-final claims data to develop and validate models for real-time estimation of admissions, readmissions, and observation stays. Results These real-time reporting models accurately estimate, within 2 months from admission, the monthly numbers of admissions, 30-day readmission and observation-stay rates for patients with AMI, HF, or pneumonia. Conclusions This work will allow CMS to track the impact of policy decisions in real time and enable hospitals to better monitor their performance nationally.
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- 2020
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21. Leading Causes of Death Among Adults Aged 25 to 44 Years by Race and Ethnicity in Texas During the COVID-19 Pandemic, March to December 2020
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Alexander Chen, Max Jordan Nguemeni Tiako, Shu-Xia Li, Harlan M. Krumholz, Michael L. Barnett, Chengan Du, and Jeremy S. Faust
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Adult ,Male ,2019-20 coronavirus outbreak ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Racial Groups ,MEDLINE ,Ethnic group ,COVID-19 ,Texas ,Race (biology) ,Cause of Death ,Pandemic ,Internal Medicine ,Research Letter ,Medicine ,Humans ,Female ,Young adult ,business ,Demography ,Cause of death - Abstract
This cohort study examines mortality data from Texas, a racially and ethnically diverse state, to better understand excess mortality among adults aged 25 to 44 years during early months of the COVID-19 pandemic.
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- 2021
22. SARS-CoV-2 Infection Hospitalization Rate and Infection Fatality Rate Among the Non-Congregant Population in Connecticut
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Albert I. Ko, Cesar Caraballo, Carrie A. Redlich, Yike Dong, Howard P. Forman, Harlan M. Krumholz, Lian Chen, Jeremy S. Faust, Sara K. Huston, Shiwani Mahajan, Rajesh Srinivasan, and Shu-Xia Li
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Male ,medicine.medical_specialty ,infection fatality rate ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Population ,infection hospitalization rate ,Disease ,030204 cardiovascular system & hematology ,Asymptomatic ,Risk Assessment ,Hospitalization rate ,COVID-19 Serological Testing ,03 medical and health sciences ,Brief Observation ,0302 clinical medicine ,Seroepidemiologic Studies ,Case fatality rate ,Outcome Assessment, Health Care ,medicine ,Disease Transmission, Infectious ,Seroprevalence ,Humans ,030212 general & internal medicine ,Mortality ,education ,education.field_of_study ,seroprevalence ,business.industry ,SARS-CoV-2 ,Public health ,Outbreak ,COVID-19 ,General Medicine ,Middle Aged ,Confidence interval ,Hospitalization ,Connecticut ,Infectious disease (medical specialty) ,Carrier State ,Communicable Disease Control ,Female ,medicine.symptom ,business ,Demography - Abstract
ImportanceCOVID-19 case fatality and hospitalization rates, calculated using the number of confirmed cases of COVID-19, have been described widely in the literature. However, the number of infections confirmed by testing underestimates the total infections as it is biased based on the availability of testing and because asymptomatic individuals may remain untested. The infection fatality rate (IFR) and infection hospitalization rate (IHR), calculated using the estimated total infections based on a representative sample of a population, is a better metric to assess the actual toll of the disease.ObjectiveTo determine the IHR and IFR for COVID-19 using the statewide SARS-CoV-2 seroprevalence estimates for the non-congregate population in Connecticut.DesignCross-sectional.SettingAdults residing in a non-congregate setting in Connecticut between March 1 and June 1, 2020.ParticipantsIndividuals aged 18 years or above.ExposureEstimated number of adults with SARS-CoV-2 antibodies.Main Outcome and MeasuresCOVID-19-related hospitalizations and deaths among adults residing in a non-congregate setting in Connecticut between March 1 and June 1, 2020.ResultsOf the 2.8 million individuals residing in the non-congregate settings in Connecticut through June 2020, 113,515 (90% CI 56,758–170,273) individuals had SARS-CoV-2 antibodies. There were a total of 9425 COVID-19-related hospitalizations and 4071 COVID-19-related deaths in Connecticut between March 1 and June 1, 2020, of which 7792 hospitalizations and 1079 deaths occurred among the non-congregate population. The overall COVID-19 IHR and IFR was 6.86% (90% CI, 4.58%–13.72%) and 0.95% (90% CI, 0.63%–1.90%) among the non-congregate population. Older individuals, men, non-Hispanic Black individuals and those belonging to New Haven and Litchfield counties had a higher burden of hospitalization and deaths, compared with younger individuals, women, non-Hispanic White or Hispanic individuals, and those belonging to New London county, respectively.Conclusion and RelevanceUsing representative seroprevalence estimates, the overall COVID-19 IHR and IFR were estimated to be 6.86% and 0.95% among the non-congregate population in Connecticut. Accurate estimation of IHR and IFR among community residents is important to guide public health strategies during an infectious disease outbreak.
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- 2021
23. Performance Metrics for the Comparative Analysis of Clinical Risk Prediction Models Employing Machine Learning.
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Chenxi Huang, Shu-Xia Li, Caraballo, César, Masoudi, Frederick A., Rumsfeld, John S., Spertus, John A., Normand, Sharon-Lise T., Mortazavi, Bobak J., Krumholz, Harlan M., Huang, Chenxi, and Li, Shu-Xia
- Abstract
Background: New methods such as machine learning techniques have been increasingly used to enhance the performance of risk predictions for clinical decision-making. However, commonly reported performance metrics may not be sufficient to capture the advantages of these newly proposed models for their adoption by health care professionals to improve care. Machine learning models often improve risk estimation for certain subpopulations that may be missed by these metrics.Methods and Results: This article addresses the limitations of commonly reported metrics for performance comparison and proposes additional metrics. Our discussions cover metrics related to overall performance, discrimination, calibration, resolution, reclassification, and model implementation. Models for predicting acute kidney injury after percutaneous coronary intervention are used to illustrate the use of these metrics.Conclusions: We demonstrate that commonly reported metrics may not have sufficient sensitivity to identify improvement of machine learning models and propose the use of a comprehensive list of performance metrics for reporting and comparing clinical risk prediction models. [ABSTRACT FROM AUTHOR]- Published
- 2021
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24. Disparities in Excess Mortality Associated with COVID-19 - United States, 2020.
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Rossen, Lauren M., Ahmad, Farida B., Anderson, Robert N., Branum, Amy M., Chengan Du, Krumholz, Harlan M., Shu-Xia Li, Zhenqiu Lin, Marshall, Andrew, Sutton, Paul D., Faust, Jeremy S., Du, Chengan, Li, Shu-Xia, and Lin, Zhenqiu
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COVID-19 ,DEATH certificates ,AGE groups ,BOX-Jenkins forecasting ,ADULTS ,BLACK people - Abstract
The COVID-19 pandemic has disproportionately affected Hispanic or Latino, non-Hispanic Black (Black), non-Hispanic American Indian or Alaska Native (AI/AN), and non-Hispanic Native Hawaiian or Other Pacific Islander (NH/PI) populations in the United States. These populations have experienced higher rates of infection and mortality compared with the non-Hispanic White (White) population (1-5) and greater excess mortality (i.e., the percentage increase in the number of persons who have died relative to the expected number of deaths for a given place and time) (6). A limitation of existing research on excess mortality among racial/ethnic minority groups has been the lack of adjustment for age and population change over time. This study assessed excess mortality incidence rates (IRs) (e.g., the number of excess deaths per 100,000 person-years) in the United States during December 29, 2019-January 2, 2021, by race/ethnicity and age group using data from the National Vital Statistics System. Among all assessed racial/ethnic groups (non-Hispanic Asian [Asian], AI/AN, Black, Hispanic, NH/PI, and White populations), excess mortality IRs were higher among persons aged ≥65 years (426.4 to 1033.5 excess deaths per 100,000 person-years) than among those aged 25-64 years (30.2 to 221.1) and those aged <25 years (-2.9 to 14.1). Among persons aged <65 years, Black and AI/AN populations had the highest excess mortality IRs. Among adults aged ≥65 years, Black and Hispanic persons experienced the highest excess mortality IRs of >1,000 excess deaths per 100,000 person-years. These findings could help guide more tailored public health messaging and mitigation efforts to reduce disparities in mortality associated with the COVID-19 pandemic in the United States,* by identifying the racial/ethnic groups and age groups with the highest excess mortality rates. [ABSTRACT FROM AUTHOR]
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- 2021
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25. Enhancing the prediction of acute kidney injury risk after percutaneous coronary intervention using machine learning techniques: A retrospective cohort study
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Frederick A. Masoudi, John S. Rumsfeld, Bobak J. Mortazavi, Francis P. Wilson, Shu-Xia Li, Wade L. Schulz, Julian S. Haimovich, Sanket S. Dhruva, Yongfei Wang, Carlos Mena, John A. Spertus, Karthik Murugiah, Chenxi Huang, Shiwani Mahajan, Jeffrey M. Testani, and Harlan M. Krumholz
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Male ,Time Factors ,Cardiovascular Procedures ,lcsh:Medicine ,030204 cardiovascular system & hematology ,computer.software_genre ,Logistic regression ,Machine Learning ,0302 clinical medicine ,Mathematical and Statistical Techniques ,Endocrinology ,Risk Factors ,Medicine and Health Sciences ,Medicine ,Data Mining ,030212 general & internal medicine ,Registries ,Statistics ,Software Engineering ,General Medicine ,Acute Kidney Injury ,Middle Aged ,Treatment Outcome ,Brier score ,Cohort ,Physical Sciences ,Engineering and Technology ,Female ,Anatomy ,Risk assessment ,Research Article ,Computer and Information Sciences ,Endocrine Disorders ,Permutation ,Clinical Decision-Making ,Surgical and Invasive Medical Procedures ,Machine learning ,Research and Analysis Methods ,Risk Assessment ,Decision Support Techniques ,03 medical and health sciences ,Percutaneous Coronary Intervention ,Artificial Intelligence ,Diabetes Mellitus ,Humans ,Statistical Methods ,Preprocessing ,Aged ,Retrospective Studies ,Receiver operating characteristic ,business.industry ,Discrete Mathematics ,lcsh:R ,Angioplasty ,Biology and Life Sciences ,Reproducibility of Results ,Retrospective cohort study ,Kidneys ,Renal System ,Protective Factors ,Confidence interval ,Combinatorics ,Metabolic Disorders ,Conventional PCI ,Artificial intelligence ,business ,computer ,Coronary Angioplasty ,Mathematics ,Forecasting - Abstract
Background The current acute kidney injury (AKI) risk prediction model for patients undergoing percutaneous coronary intervention (PCI) from the American College of Cardiology (ACC) National Cardiovascular Data Registry (NCDR) employed regression techniques. This study aimed to evaluate whether models using machine learning techniques could significantly improve AKI risk prediction after PCI. Methods and findings We used the same cohort and candidate variables used to develop the current NCDR CathPCI Registry AKI model, including 947,091 patients who underwent PCI procedures between June 1, 2009, and June 30, 2011. The mean age of these patients was 64.8 years, and 32.8% were women, with a total of 69,826 (7.4%) AKI events. We replicated the current AKI model as the baseline model and compared it with a series of new models. Temporal validation was performed using data from 970,869 patients undergoing PCIs between July 1, 2016, and March 31, 2017, with a mean age of 65.7 years; 31.9% were women, and 72,954 (7.5%) had AKI events. Each model was derived by implementing one of two strategies for preprocessing candidate variables (preselecting and transforming candidate variables or using all candidate variables in their original forms), one of three variable-selection methods (stepwise backward selection, lasso regularization, or permutation-based selection), and one of two methods to model the relationship between variables and outcome (logistic regression or gradient descent boosting). The cohort was divided into different training (70%) and test (30%) sets using 100 different random splits, and the performance of the models was evaluated internally in the test sets. The best model, according to the internal evaluation, was derived by using all available candidate variables in their original form, permutation-based variable selection, and gradient descent boosting. Compared with the baseline model that uses 11 variables, the best model used 13 variables and achieved a significantly better area under the receiver operating characteristic curve (AUC) of 0.752 (95% confidence interval [CI] 0.749–0.754) versus 0.711 (95% CI 0.708–0.714), a significantly better Brier score of 0.0617 (95% CI 0.0615–0.0618) versus 0.0636 (95% CI 0.0634–0.0638), and a better calibration slope of observed versus predicted rate of 1.008 (95% CI 0.988–1.028) versus 1.036 (95% CI 1.015–1.056). The best model also had a significantly wider predictive range (25.3% versus 21.6%, p < 0.001) and was more accurate in stratifying AKI risk for patients. Evaluated on a more contemporary CathPCI cohort (July 1, 2015–March 31, 2017), the best model consistently achieved significantly better performance than the baseline model in AUC (0.785 versus 0.753), Brier score (0.0610 versus 0.0627), calibration slope (1.003 versus 1.062), and predictive range (29.4% versus 26.2%). The current study does not address implementation for risk calculation at the point of care, and potential challenges include the availability and accessibility of the predictors. Conclusions Machine learning techniques and data-driven approaches resulted in improved prediction of AKI risk after PCI. The results support the potential of these techniques for improving risk prediction models and identification of patients who may benefit from risk-mitigation strategies., In a retrospective cohort study, Harlan M. Krumholz and colleagues use machine learning techniques in an effort to improve identification of PCI patients who may benefit from AKI risk-mitigation strategies., Author summary Why was this study done? Accurately estimating the risk of developing acute kidney injury (AKI) is important to determine revascularization strategies and inform peri- and postprocedural care. The current AKI risk prediction model was developed by employing prior clinical knowledge to choose and transform candidate variables and applying regression techniques. It is unknown whether and how machine learning techniques could improve predictive performance from the current AKI risk model. What did the researchers do and find? We used data from 947,091 percutaneous coronary intervention (PCI) procedures from the National Cardiovascular Data Registry (NCDR) CathPCI registry to develop AKI prediction models, the same data from which the current AKI risk model was derived. Temporal validation was performed on a more contemporary cohort of 970,869 PCIs from the NCDR CathPCI registry. We compared the performance of the current AKI risk model with a series of new AKI risk models, which were derived using different regression and machine learning techniques. An AKI risk model derived from machine learning techniques had significantly better discrimination, calibration, and risk stratification than the current AKI risk model in both the internal test set and temporal validation set. What do these findings mean? The demonstrated improvement in predictive power supports the potential of machine learning techniques for improving risk prediction modeling. The improved prediction for AKI suggests great potential of the model to improve targeting of risk-mitigation treatment and quality assessment of cardiovascular care. Future studies need to assess the feasibility of integrating the machine learning model into clinical care and evaluate the benefit of the model for patients at the point of care.
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- 2018
26. Quantifying the utilization of medical devices necessary to detect postmarket safety differences: A case study of implantable cardioverter defibrillators
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Jonathan Bates, Joseph S. Ross, Harlan M. Krumholz, Richard Kuntz, Richard E. Shaw, Andreas Coppi, Shu-Xia Li, Craig S. Parzynski, Sanket S. Dhruva, Frederick A. Masoudi, Frederick Warner, and Danica Marinac-Dabic
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medicine.medical_specialty ,Medical device ,Databases, Factual ,Epidemiology ,030204 cardiovascular system & hematology ,Rate ratio ,Article ,Implantable defibrillators ,Prosthesis Implantation ,03 medical and health sciences ,0302 clinical medicine ,Statistical significance ,medicine ,Product Surveillance, Postmarketing ,Humans ,Pharmacology (medical) ,030212 general & internal medicine ,Registries ,Cardiac Surgical Procedures ,Adverse effect ,Heart Failure ,business.industry ,Pharmacoepidemiology ,United States ,Defibrillators, Implantable ,Prosthesis Failure ,Primary Prevention ,Death, Sudden, Cardiac ,Sample size determination ,Data Interpretation, Statistical ,Sample Size ,Emergency medicine ,business - Abstract
PURPOSE: To estimate medical device utilization needed to detect safety differences among implantable cardioverter defibrillators (ICDs) generator models and compare these estimates to utilization in practice. METHODS: We conducted repeated sample size estimates to calculate the medical device utilization needed, systematically varying device‐specific safety event rate ratios and significance levels while maintaining 80% power, testing 3 average adverse event rates (3.9, 6.1, and 12.6 events per 100 person‐years) estimated from the American College of Cardiology’s 2006 to 2010 National Cardiovascular Data Registry of ICDs. We then compared with actual medical device utilization. RESULTS: At significance level 0.05 and 80% power, 34% or fewer ICD models accrued sufficient utilization in practice to detect safety differences for rate ratios
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- 2018
27. Can machine learning complement traditional medical device surveillance? A case-study of dual-chamber implantable cardioverter–defibrillators
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Isuru Ranasinghe, Richard E. Shaw, Nihar R. Desai, Jeptha P. Curtis, Sharon-Lise T. Normand, Danica Marinac-Dabic, Joseph S. Ross, Richard Kuntz, Ginger M. Gamble, Joseph G. Akar, Shu-Xia Li, Craig S. Parzynski, Harlan M. Krumholz, Frederick A. Masoudi, Jonathan Bates, and James V. Freeman
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Medical device ,Evidence and Research [Medical Devices] ,Biomedical Engineering ,Medicine (miscellaneous) ,Feature selection ,030204 cardiovascular system & hematology ,Machine learning ,computer.software_genre ,03 medical and health sciences ,0302 clinical medicine ,implanted cardioverter–defibrillator ,Medicine ,Cumulative incidence ,030212 general & internal medicine ,Original Research ,Complement (set theory) ,Event (probability theory) ,business.industry ,methodology ,medicine.disease ,Ensemble learning ,3. Good health ,Data extraction ,Propensity score matching ,surveillance ,Artificial intelligence ,Medical emergency ,business ,computer - Abstract
Joseph S Ross,1–4 Jonathan Bates,4 Craig S Parzynski,4 Joseph G Akar,4,5 Jeptha P Curtis,4,5 Nihar R Desai,4,5 James V Freeman,4,5 Ginger M Gamble,4 Richard Kuntz,6 Shu-Xia Li,4 Danica Marinac-Dabic,7 Frederick A Masoudi,8 Sharon-Lise T Normand,9,10 Isuru Ranasinghe,11 Richard E Shaw,12 Harlan M Krumholz2–5 1Section of General Medicine, Department of Medicine, 2Robert Wood Johnson Foundation Clinical Scholars Program, Yale School of Medicine, 3Department of Health Policy and Management, Yale School of Public Health, 4Center for Outcomes Research and Evaluation, Yale–New Haven Hospital, 5Section of Cardiovascular Medicine, Department of Medicine, Yale School of Medicine, New Haven, CT, 6Medtronic Inc, Minneapolis, MN, 7Division of Epidemiology, Center for Devices and Radiological Health, US Food and Drug Administration, Silver Spring, MD, 8Division of Cardiology, Department of Medicine, University of Colorado, Aurora, CO, 9Department of Health Care Policy, Harvard Medical School, 10Department of Biostatistics, Harvard TH Chan School of Public Health, Boston, MA, USA; 11Discipline of Medicine, University of Adelaide, Adelaide, SA, Australia; 12Department of Clinical Informatics, California Pacific Medical Center, San Francisco, CA, USA Background: Machine learning methods may complement traditional analytic methods for medical device surveillance.Methods and results: Using data from the National Cardiovascular Data Registry for implantable cardioverter–defibrillators (ICDs) linked to Medicare administrative claims for longitudinal follow-up, we applied three statistical approaches to safety-signal detection for commonly used dual-chamber ICDs that used two propensity score (PS) models: one specified by subject-matter experts (PS-SME), and the other one by machine learning-based selection (PS-ML). The first approach used PS-SME and cumulative incidence (time-to-event), the second approach used PS-SME and cumulative risk (Data Extraction and Longitudinal Trend Analysis [DELTA]), and the third approach used PS-ML and cumulative risk (embedded feature selection). Safety-signal surveillance was conducted for eleven dual-chamber ICD models implanted at least 2,000 times over 3 years. Between 2006 and 2010, there were 71,948 Medicare fee-for-service beneficiaries who received dual-chamber ICDs. Cumulative device-specific unadjusted 3-year event rates varied for three surveyed safety signals: death from any cause, 12.8%–20.9%; nonfatal ICD-related adverse events, 19.3%–26.3%; and death from any cause or nonfatal ICD-related adverse event, 27.1%–37.6%. Agreement among safety signals detected/not detected between the time-to-event and DELTA approaches was 90.9% (360 of 396, k=0.068), between the time-to-event and embedded feature-selection approaches was 91.7% (363 of 396, k=–0.028), and between the DELTA and embedded feature selection approaches was 88.1% (349 of 396, k=–0.042).Conclusion: Three statistical approaches, including one machine learning method, identified important safety signals, but without exact agreement. Ensemble methods may be needed to detect all safety signals for further evaluation during medical device surveillance. Keywords: implanted cardioverter–defibrillator, methodology, surveillance
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- 2017
28. Discovery of temporal and disease association patterns in condition-specific hospital utilization rates
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Harlan M. Krumholz, Frederick Warner, Julian S. Haimovich, Shu-Xia Li, Arjun K. Venkatesh, Abbas Shojaee, and Andreas Coppi
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Databases, Factual ,Pulmonology ,lcsh:Medicine ,Geographical locations ,0302 clinical medicine ,Statistics ,Medicine and Health Sciences ,Cluster Analysis ,Spectral analysis ,030212 general & internal medicine ,lcsh:Science ,Ovarian Neoplasms ,Multidisciplinary ,Patient Discharge ,Hospitals ,3. Good health ,Hospitalization ,Variation (linguistics) ,Acute Disease ,Female ,Seasons ,Research Article ,Patients ,Summer ,New York ,Disease Association ,Biology ,03 medical and health sciences ,medicine ,Hospital utilization ,Humans ,Cluster analysis ,Tuberculosis, Pulmonary ,Inpatients ,Models, Statistical ,Winter ,lcsh:R ,Seasonality ,medicine.disease ,United States ,Administrative claims ,Health Care ,Harmonic regression ,Health Care Facilities ,Respiratory Infections ,North America ,Schizophrenia ,Earth Sciences ,lcsh:Q ,People and places ,Seasonal Variations ,Administrative Claims, Healthcare ,030217 neurology & neurosurgery - Abstract
Identifying temporal variation in hospitalization rates may provide insights about disease patterns and thereby inform research, policy, and clinical care. However, the majority of medical conditions have not been studied for their potential seasonal variation. The objective of this study was to apply a data-driven approach to characterize temporal variation in condition-specific hospitalizations. Using a dataset of 34 million inpatient discharges gathered from hospitals in New York State from 2008–2011, we grouped all discharges into 263 clinical conditions based on the principal discharge diagnosis using Clinical Classification Software in order to mitigate the limitation that administrative claims data reflect clinical conditions to varying specificity. After applying Seasonal-Trend Decomposition by LOESS, we estimated the periodicity of the seasonal component using spectral analysis and applied harmonic regression to calculate the amplitude and phase of the condition’s seasonal utilization pattern. We also introduced four new indices of temporal variation: mean oscillation width, seasonal coefficient, trend coefficient, and linearity of the trend. Finally, K-means clustering was used to group conditions across these four indices to identify common temporal variation patterns. Of all 263 clinical conditions considered, 164 demonstrated statistically significant seasonality. Notably, we identified conditions for which seasonal variation has not been previously described such as ovarian cancer, tuberculosis, and schizophrenia. Clustering analysis yielded three distinct groups of conditions based on multiple measures of seasonal variation. Our study was limited to New York State and results may not directly apply to other regions with distinct climates and health burden. A substantial proportion of medical conditions, larger than previously described, exhibit seasonal variation in hospital utilization. Moreover, the application of clustering tools yields groups of clinically heterogeneous conditions with similar seasonal phenotypes. Further investigation is necessary to uncover common etiologies underlying these shared seasonal phenotypes.
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- 2017
29. Treatment for Multiple Acute Cardiopulmonary Conditions Among Older Patients Hospitalized with Pneumonia, Chronic Obstructive Pulmonary Disease, or Heart Failure
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Joanne Lynn, Frank R. Ernst, Mary E. Tinetti, Harlan M. Krumholz, Michelle R. Krukas, Shu-Xia Li, Tara Lagu, Peter K. Lindenauer, Kumar Dharmarajan, and Kelly M. Strait
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Male ,medicine.medical_specialty ,Cardiotonic Agents ,Cross-sectional study ,Vasodilator Agents ,Comorbidity ,030204 cardiovascular system & hematology ,Article ,Cohort Studies ,03 medical and health sciences ,Pulmonary Disease, Chronic Obstructive ,0302 clinical medicine ,Adrenal Cortex Hormones ,Internal medicine ,medicine ,Humans ,030212 general & internal medicine ,Intensive care medicine ,Diuretics ,Aged ,Retrospective Studies ,Aged, 80 and over ,Heart Failure ,COPD ,business.industry ,Retrospective cohort study ,Pneumonia ,medicine.disease ,United States ,respiratory tract diseases ,Hospital medicine ,Anti-Bacterial Agents ,Hospitalization ,Cross-Sectional Studies ,Heart failure ,Drug Therapy, Combination ,Female ,Geriatrics and Gerontology ,business ,Cohort study - Abstract
Objectives To determine how often hospitalized older adults principally diagnosed with pneumonia, chronic obstructive pulmonary disease (COPD), or heart failure (HF) are concurrently treated for two or more of these acute cardiopulmonary conditions. Design Retrospective cohort study. Setting 368 U.S. hospitals in the Premier research database. Participants Individuals aged 65 and older principally hospitalized with pneumonia, COPD, or HF in 2009 or 2010. Measurements Proportion of diagnosed episodes of pneumonia, COPD, or HF concurrently treated for two or more of these acute cardiopulmonary conditions during the first 2 hospital days. Results Of 91,709 diagnosed pneumonia hospitalizations, 32% received treatment for two or more acute cardiopulmonary conditions (18% for HF, 18% for COPD, 4% for both). Of 41,052 diagnosed COPD hospitalizations, 19% received treatment for two or more acute cardiopulmonary conditions (all of which involved additional HF treatment). Of 118,061 diagnosed HF hospitalizations, 38% received treatment for two or more acute cardiopulmonary conditions (34% for pneumonia, 9% for COPD, 5% for both). Conclusion Hospitalized older adults diagnosed with pneumonia, COPD, or HF are frequently treated for two or more acute cardiopulmonary conditions, suggesting that clinical syndromes often fall between traditional diagnostic categories. Research is needed to evaluate the risks and benefits of real-world treatment for the many older adults whose presentations elicit diagnostic uncertainty or concern about coexisting acute conditions.
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- 2016
30. Hospital Variation in Admission to Intensive Care Units for Patients with Acute Myocardial Infarction
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Frederick A. Masoudi, John Martin, Colin R. Cooke, Brahmajee K. Nallamothu, Reza Fazel, Kelly M. Strait, Kumar Dharmarajan, Shu-Xia Li, Ruijun Chen, Harlan M. Krumholz, and Isuru Ranasinghe
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Mechanical ventilation ,medicine.medical_specialty ,business.industry ,health care facilities, manpower, and services ,medicine.medical_treatment ,Mortality rate ,Retrospective cohort study ,medicine.disease ,Triage ,Article ,Quartile ,Intensive care ,Emergency medicine ,Health care ,medicine ,Myocardial infarction ,Cardiology and Cardiovascular Medicine ,business - Abstract
Background The treatment for patients with acute myocardial infarction (AMI) was transformed by the introduction of intensive care units (ICUs), yet we know little about how contemporary hospitals use this resource-intensive setting and whether higher use is associated with better outcomes. Methods We identified 114,136 adult hospitalizations for AMI from 307 hospitals in the 2009 to 2010 Premier database using codes from the International Classification of Diseases, Ninth Revision, Clinical Modification . Hospitals were stratified into quartiles by rates of ICU admission for AMI patients. Across quartiles, we examined in-hospital risk-standardized mortality rates and usage rates of critical care therapies for these patients. Results Rates of ICU admission for AMI patients varied markedly among hospitals (median 48%, Q1-Q4 20%-71%, range 0%-98%), and there was no association with in-hospital risk-standardized mortality rates (6% all quartiles, P = .7). However, hospitals admitting more AMI patients to the ICU were more likely to use critical care therapies overall (mechanical ventilation [from Q1 with lowest rate of ICU use to Q4 with highest rate 13%-16%], vasopressors/inotropes [17%-21%], intra-aortic balloon pumps [4%-7%], and pulmonary artery catheters [4%-5%]; P for trend Conclusions Rates of ICU admission for patients with AMI vary substantially across hospitals and were not associated with differences in mortality, but were associated with greater use of critical care therapies. These findings suggest uncertainty about the appropriate use of this resource-intensive setting and a need to optimize ICU triage for patients who will truly benefit.
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- 2015
31. Dynamic Modeling of Steam Condenser and Design of PI Controller Based on Grey Wolf Optimizer
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Jie-Sheng Wang and Shu-Xia Li
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Engineering ,Article Subject ,business.industry ,General Mathematics ,lcsh:Mathematics ,General Engineering ,PID controller ,Control engineering ,Surface condenser ,lcsh:QA1-939 ,Control theory ,lcsh:TA1-2040 ,Control system ,Genetic algorithm ,Heat exchanger ,MATLAB ,business ,lcsh:Engineering (General). Civil engineering (General) ,computer ,Metaheuristic ,Condenser (heat transfer) ,computer.programming_language - Abstract
Shell-and-tube condenser is a heat exchanger for cooling steam with high temperature and pressure, which is one of the main kinds of heat exchange equipment in thermal, nuclear, and marine power plant. Based on the lumped parameter modeling method, the dynamic mathematical model of the simplified steam condenser is established. Then, the pressure PI control system of steam condenser based on the Matlab/Simulink simulation platform is designed. In order to obtain better performance, a new metaheuristic intelligent algorithm, grey wolf optimizer (GWO), is used to realize the fine-tuning of PI controller parameters. On the other hand, the Z-N engineering tuning method, genetic algorithm, and particle swarm algorithm are adopted for tuning PI controller parameters and compared with GWO algorithm. Simulation results show that GWO algorithm has better control performance than other four algorithms.
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- 2015
32. Cuckoo Search Algorithm Based on Repeat-Cycle Asymptotic Self-Learning and Self-Evolving Disturbance for Function Optimization
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Jiang-di Song, Jie-Sheng Wang, and Shu-xia Li
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Mathematical optimization ,Disturbance (geology) ,Time Factors ,General Computer Science ,Article Subject ,General Mathematics ,Computer Science::Neural and Evolutionary Computation ,lcsh:Computer applications to medicine. Medical informatics ,Swarm intelligence ,Pattern Recognition, Automated ,lcsh:RC321-571 ,Birds ,Convergence (routing) ,Derivative-free optimization ,Animals ,Learning ,Multi-swarm optimization ,Cuckoo search ,Metaheuristic ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Mathematics ,Problem Behavior ,Behavior, Animal ,General Neuroscience ,Particle swarm optimization ,General Medicine ,Models, Theoretical ,lcsh:R858-859.7 ,Algorithm ,Algorithms ,Research Article - Abstract
In order to improve convergence velocity and optimization accuracy of the cuckoo search (CS) algorithm for solving the function optimization problems, a new improved cuckoo search algorithm based on the repeat-cycle asymptotic self-learning and self-evolving disturbance (RC-SSCS) is proposed. A disturbance operation is added into the algorithm by constructing a disturbance factor to make a more careful and thorough search near the bird’s nests location. In order to select a reasonable repeat-cycled disturbance number, a further study on the choice of disturbance times is made. Finally, six typical test functions are adopted to carry out simulation experiments, meanwhile, compare algorithms of this paper with two typical swarm intelligence algorithms particle swarm optimization (PSO) algorithm and artificial bee colony (ABC) algorithm. The results show that the improved cuckoo search algorithm has better convergence velocity and optimization accuracy.
- Published
- 2015
33. Suicide Deaths During the COVID-19 Stay-at-Home Advisory in Massachusetts, March to May 2020.
- Author
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Faust, Jeremy Samuel, Shah, Sejal B., Chengan Du, Shu-Xia Li, Zhenqiu Lin, and Krumholz, Harlan M.
- Published
- 2021
- Full Text
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34. Optimal Decisions in a Sea-Cargo Supply Chain with Two Competing Freight Forwarders Considering Altruistic Preference and Brand Investment
- Author
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Xiao-Ying Ma, Duo-Qing Sun, Shu-Xia Liu, Yue-Ting Li, Hui-Quan Ma, Ling-Min Zhang, and Xia Li
- Subjects
sea-cargo supply chain ,altruistic preference ,brand investment ,optimal decision ,competition for freight forwarders ,Systems engineering ,TA168 ,Technology (General) ,T1-995 - Abstract
Maritime transportation is a crucial component of international cargo transport, offering several advantages, such as route flexibility, large capacity, and cost-effectiveness. The competition and collaboration among the node enterprises in the sea-cargo supply chain system (SCSCS) directly impact the overall structure and efficiency of the supply chain system, introducing complexity in analysis. This research focuses on a two-level SCSCS comprising one shipping company and two competing freight forwarders, considering their altruistic preferences manifested through contributing to the shipping company’s brand building. Employing a Stackelberg game model, this study examines the effects of the shipping company’s brand investment willingness and the freight forwarders’ altruistic preferences on the decision making and profits of all stakeholders. The findings reveal that a higher willingness of the shipping company to invest in its brand building leads to increased profits for all parties involved. However, while the altruistic behaviors of the freight forwarders can enhance the shipping company’s profits, their own profits may not necessarily see the same impact. Furthermore, moderate competition between the freight forwarders can enhance the profits for all members. This research identifies the circumstances in which the freight forwarders’ altruistic preferences can lead to increased profits for themselves, achieving both altruistic and self-interested outcomes.
- Published
- 2023
- Full Text
- View/download PDF
35. Fabricating polyoxometalates-stabilized single-atom site catalysts in confined space with enhanced activity for alkynes diboration
- Author
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Yiwei Liu, Xi Wu, Zhi Li, Jian Zhang, Shu-Xia Liu, Shoujie Liu, Lin Gu, Li Rong Zheng, Jia Li, Dingsheng Wang, and Yadong Li
- Subjects
Science - Abstract
It is of great significance to exert the synergistic effect between single atom and support. Here, the authors prepare polyoxometalates-stabilized single-atom site catalysts in confined space with enhanced activity for alkynes diboration.
- Published
- 2021
- Full Text
- View/download PDF
36. Procedure Intensity and the Cost of Care
- Author
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Peter K. Lindenauer, Kyan C. Safavi, Nancy Kim, Harlan M. Krumholz, Kelly M. Strait, Kumar Dharmarajan, Serene I. Chen, Tara Lagu, and Shu-Xia Li
- Subjects
Adult ,Male ,Pediatrics ,medicine.medical_specialty ,Percutaneous ,Time Factors ,Wilcoxon signed-rank test ,Adolescent ,Cross-sectional study ,Hospitals, Rural ,MEDLINE ,Risk Assessment ,Article ,Young Adult ,Hospitals, Urban ,Residence Characteristics ,Risk Factors ,medicine ,Humans ,Hospital Mortality ,Young adult ,Hospital Costs ,Hospitals, Teaching ,Aged ,Aged, 80 and over ,Heart Failure ,business.industry ,Length of Stay ,Middle Aged ,medicine.disease ,United States ,Hospitalization ,Cross-Sectional Studies ,Models, Economic ,Outcome and Process Assessment, Health Care ,Treatment Outcome ,Hospital Bed Capacity ,Heart failure ,Costs and Cost Analysis ,Linear Models ,Female ,Cardiology and Cardiovascular Medicine ,Cost of care ,business ,Risk assessment - Abstract
Background— The intensive practice style of hospitals with high procedure rates may result in higher costs of care for medically managed patients. We sought to determine how costs for patients with heart failure (HF) not receiving procedures compare between hospital groups defined by their overall use of procedures. Methods and Results— We identified all 2009 to 2010 adult HF hospitalizations in hospitals capable of performing invasive procedures that had at least 25 HF hospitalizations in the Perspective database from Premier, Inc. We divided hospitals into 2 groups by the proportion of patients with HF receiving invasive percutaneous or surgical procedures: low (>0%–10%) and high (≥10%). The standard costs of hospitalizations at each hospital were risk adjusted using patient demographics and comorbidities. We used the Wilcoxon rank sum test to assess cost, length of stay, and mortality outcome differences between the 2 groups. Median risk-standardized costs among low-procedural HF hospitalizations were $5259 (interquartile range, $4683–$6814) versus $6965 (interquartile range, $5981–$8235) for hospitals with high procedure use ( P P =0.009). We did not identify any single service area that explained the difference in costs between hospital groups, but these hospitals had higher costs for most service areas. Conclusion— Among patients who do not receive invasive procedures, the cost of HF hospitalization is higher in more procedure-intense hospitals compared with hospitals that perform fewer procedures.
- Published
- 2012
37. Changes in Gene Expression Predicting Local Control in Cervical Cancer: Results from Radiation Therapy Oncology Group 0128
- Author
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Shu-Xia Li, Adam P. Dicker, J. Ryu, Bridgette Miller, David K. Gaffney, Kathryn Winter, Joanne B. Weidhaas, and Anuja Jhingran
- Subjects
Oncology ,Cancer Research ,medicine.medical_specialty ,medicine.medical_treatment ,Uterine Cervical Neoplasms ,Antineoplastic Agents ,Article ,Internal medicine ,Gene expression ,medicine ,Combined Modality Therapy ,Humans ,Cyclooxygenase Inhibitors ,Oligonucleotide Array Sequence Analysis ,Cisplatin ,Cervical cancer ,Chemotherapy ,Sulfonamides ,business.industry ,Gene Expression Profiling ,medicine.disease ,Prognosis ,Radiation therapy ,Gene expression profiling ,Celecoxib ,Pyrazoles ,Female ,Radiotherapy, Adjuvant ,business ,medicine.drug - Abstract
Purpose: To evaluate the potential of gene expression signatures to predict response to treatment in locally advanced cervical cancer treated with definitive chemotherapy and radiation. Experimental Design: Tissue biopsies were collected from patients participating in Radiation Therapy Oncology Group (RTOG) 0128, a phase II trial evaluating the benefit of celecoxib in addition to cisplatin chemotherapy and radiation for locally advanced cervical cancer. Gene expression profiling was done and signatures of pretreatment, mid-treatment (before the first implant), and “changed” gene expression patterns between pre- and mid-treatment samples were determined. The ability of the gene signatures to predict local control versus local failure was evaluated. Two-group t test was done to identify the initial gene set separating these end points. Supervised classification methods were used to enrich the gene sets. The results were further validated by leave-one-out and 2-fold cross-validation. Results: Twenty-two patients had suitable material from pretreatment samples for analysis, and 13 paired pre- and mid-treatment samples were obtained. The changed gene expression signatures between the pre- and mid-treatment biopsies predicted response to treatment, separating patients with local failures from those who achieved local control with a seven-gene signature. The in-sample prediction rate, leave-one-out prediction rate, and 2-fold prediction rate are 100% for this seven-gene signature. This signature was enriched for cell cycle genes. Conclusions: Changed gene expression signatures during therapy in cervical cancer can predict outcome as measured by local control. After further validation, such findings could be applied to direct additional therapy for cervical cancer patients treated with chemotherapy and radiation.
- Published
- 2009
38. Genome-wide identification, phylogeny and expression analysis of the bZIP gene family in Alfalfa (Medicago sativa)
- Author
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Shu-Xia Liu, Bin Qin, Qing-xi Fang, Wen-Jing Zhang, Zhe-Yu Zhang, Yang-Cheng Liu, Wei-Jia Li, Chao Du, Xian-xian Liu, You-li Zhang, and Yong-Xia Guo
- Subjects
msbzip ,identification ,motif ,cis-acting element ,collinearity ,expression analysis ,Biotechnology ,TP248.13-248.65 - Abstract
Among eukaryotic transcription factors, the basic leucine zipper (bZIP) transcription factor is the most widely distributed and the most conserved protein. Alfalfa (Medicago sativa) is the largest forage crop in the world. However, few studies have evaluated the bZIP family in Alfalfa. In this study, bZIP genes in Alfalfa were identified, with 57 MsbZIPs being distributed into 11 sub-families in the phylogenetic tree. Motif and gene structure analysis revealed that the eleven subfamilies had similar motifs and gene structures, 15 cis-acting elements in MsbZIPs, including eight elements in hormones and four in plant stress resistance; 57 MsbZIPs were localized on 8 chromosomes, among which chr3 and chr4 had more collinearities, and MsbZIPs had more collinearity with the soybean. Tissue specific expression revealed that MsbZIPs were highly expressed in leaves and roots. These findings formed a foundation for further studies on functional characteristics, evolution and biological functions of bZIP transcription factors in alfalfa.
- Published
- 2021
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39. Can machine learning complement traditional medical device surveillance? A case study of dualchamber implantable cardioverter-defibrillators.
- Author
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Ross, Joseph S., Bates, Jonathan, Parzynski, Craig S., Akar, Joseph G., Curtis, Jeptha P., Desai, Nihar R., Freeman, James V., Gamble, Ginger M., Kuntz, Richard, Shu-Xia Li, Marinac-Dabic, Danica, Masoudi, Frederick A., Normand, Sharon-Lise T., Ranasinghe, Isuru, Shaw, Richard E., and Krumholz, Harlan M.
- Subjects
MACHINE learning ,DEFIBRILLATORS ,COMPUTERS in medicine ,MEDICAL equipment ,PUBLIC health surveillance - Abstract
Background: Machine learning methods may complement traditional analytic methods for medical device surveillance. Methods and results: Using data from the National Cardiovascular Data Registry for implantable cardioverter-defibrillators (ICDs) linked to Medicare administrative claims for longitudinal follow-up, we applied three statistical approaches to safety-signal detection for commonly used dual-chamber ICDs that used two propensity score (PS) models: one specified by subject-matter experts (PS-SME), and the other one by machine learning-based selection (PS-ML). The first approach used PS-SME and cumulative incidence (time-to-event), the second approach used PS-SME and cumulative risk (Data Extraction and Longitudinal Trend Analysis [DELTA]), and the third approach used PS-ML and cumulative risk (embedded feature selection). Safety-signal surveillance was conducted for eleven dual-chamber ICD models implanted at least 2,000 times over 3 years. Between 2006 and 2010, there were 71,948 Medicare fee-for-service beneficiaries who received dual-chamber ICDs. Cumulative device-specific unadjusted 3-year event rates varied for three surveyed safety signals: death from any cause, 12.8%-20.9%; nonfatal ICDrelated adverse events, 19.3%-26.3%; and death from any cause or nonfatal ICD-related adverse event, 27.1%-37.6%. Agreement among safety signals detected/not detected between the time-to-event and DELTA approaches was 90.9% (360 of 396, k=0.068), between the time-to-event and embedded feature-selection approaches was 91.7% (363 of 396, k=-0.028), and between the DELTA and embedded feature selection approaches was 88.1% (349 of 396, k=-0.042). Conclusion: Three statistical approaches, including one machine learning method, identified important safety signals, but without exact agreement. Ensemble methods may be needed to detect all safety signals for further evaluation during medical device surveillance. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
40. Heterogeneity in Early Responses in ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial).
- Author
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Dhruva, Sanket S., Chenxi Huang, Spatz, Erica S., Coppi, Andreas C., Warner, Frederick, Shu-Xia Li, Haiqun Lin, Xiao Xu, Furberg, Curt D., Davis, Barry R., Pressel, Sara L., Coifman, Ronald R., Krumholz, Harlan M., Huang, Chenxi, Li, Shu-Xia, Lin, Haiqun, and Xu, Xiao
- Abstract
Randomized trials of hypertension have seldom examined heterogeneity in response to treatments over time and the implications for cardiovascular outcomes. Understanding this heterogeneity, however, is a necessary step toward personalizing antihypertensive therapy. We applied trajectory-based modeling to data on 39 763 study participants of the ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial) to identify distinct patterns of systolic blood pressure (SBP) response to randomized medications during the first 6 months of the trial. Two trajectory patterns were identified: immediate responders (85.5%), on average, had a decreasing SBP, whereas nonimmediate responders (14.5%), on average, had an initially increasing SBP followed by a decrease. Compared with those randomized to chlorthalidone, participants randomized to amlodipine (odds ratio, 1.20; 95% confidence interval [CI], 1.10-1.31), lisinopril (odds ratio, 1.88; 95% CI, 1.73-2.03), and doxazosin (odds ratio, 1.65; 95% CI, 1.52-1.78) had higher adjusted odds ratios associated with being a nonimmediate responder (versus immediate responder). After multivariable adjustment, nonimmediate responders had a higher hazard ratio of stroke (hazard ratio, 1.49; 95% CI, 1.21-1.84), combined cardiovascular disease (hazard ratio, 1.21; 95% CI, 1.11-1.31), and heart failure (hazard ratio, 1.48; 95% CI, 1.24-1.78) during follow-up between 6 months and 2 years. The SBP response trajectories provided superior discrimination for predicting downstream adverse cardiovascular events than classification based on difference in SBP between the first 2 measurements, SBP at 6 months, and average SBP during the first 6 months. Our findings demonstrate heterogeneity in response to antihypertensive therapies and show that chlorthalidone is associated with more favorable initial response than the other medications. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
41. A two-stage stochastic programming model for rail-truck intermodal network design with uncertain customer demand.
- Author
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Shu-Xia Li, Si-Fan Sun, Yi-Fan Wu, and Li-Ping Liu
- Subjects
- *
RAILROAD design & construction , *STOCHASTIC programming , *CONTAINERIZATION , *SUPPLY chains , *COST effectiveness - Abstract
With the globalization of supply chains, intermodal operations have become a key player in transportation. In real life, the consumer's demands are often uncertain. The recent literature is rich of papers that either emphasizes on uncertain customer demands or intermodal transportation planning. In this paper, we combine these two fields in order to identify new potentials for saving cost and improving the efficiency of intermodal logistics network. A two stage stochastic programming model was proposed to decide the terminal location and transportation routes under uncertain customer demands. And the AP data set is used to test the presented model. The result is compared with the traditional counterparts, which shows superiority in solution quantity under uncertain environment. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
42. PID Decoupling Controller Design for Electroslag Remelting Process Using Cuckoo Search Algorithm with Self-tuning Dynamic Searching Mechanism.
- Author
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Jie-Sheng Wang and Shu-Xia Li
- Subjects
- *
PID controllers , *MATHEMATICAL decoupling , *ELECTROSLAG process , *SEARCH algorithms , *SELF-tuning controllers , *MATHEMATICAL optimization ,DESIGN & construction - Abstract
Mathematical model of electroslag remelting (ESR) process is established based on its technique features and dynamic characteristics. A new multivariable self-tuning PID controller tuned optimally by an improved cuckoo search algorithm is proposed to control the two-input-two output (TITO) ESR process. In order to improve the convergence velocity and optimization accuracy of cuckoo search (CS) algorithm, a new searching mechanism with a learning-evolving searching guider is proposed by combining the learning-evolving thought with Gaussian distribution. Then the new searching mechanism is combined with the Levy Flight searching mechanism according to a selection probability so as to form a new searching mechanism cuckoo search (MCS) algorithm. For solving the problem that the search space size and the scope cannot be decided exactly, a self-tuning dynamic searching space strategy is put forward. The search space is adjusted dynamically by following the best bird's nest location. Finally, the new searching mechanism cuckoo search algorithm with self-tuning dynamic search space (DMCS) is applied to the multivariable self-tuning PID decoupling controller. The simulation results show that the proposed control strategy can overcome dynamic conditions and the coupling problem of the system within a wide range, and it has an excellent control quality, stronger robustness and good working adaptability. [ABSTRACT FROM AUTHOR]
- Published
- 2017
43. Improved Cuckoo Search Algorithm with Novel Searching Mechanism for Solving Unconstrained Function Optimization Problem.
- Author
-
Shu-Xia Li and Jie-Sheng Wang
- Subjects
SEARCH algorithms ,MATHEMATICAL optimization ,SPAWNING ,GAUSSIAN distribution ,LEVY processes - Abstract
Cuckoo search (CS) algorithm is a new biological heuristic algorithm and simulates the cuckoo's seeking nest and spawning behavior and introduces levy flight mechanism. In order to improve the convergence velocity and optimization accuracy of cuckoo search algorithm, by combining the learning-evolving thought with Gaussian distribution, a new searching mechanism that with a learning-evolving searching guider is proposed. Then combining the new searching mechanism proposed with the Levy Flight searching mechanism according to a selection probability, a new searching mechanism cuckoo search (MCS) algorithm is formed. The result of functions testing under different dimensions proves the superiority of new proposed MCS algorithm. [ABSTRACT FROM AUTHOR]
- Published
- 2017
44. Complement factor B knockdown by short hairpin RNA inhibits laser-induced choroidal neovascularization in rats
- Author
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Xin Wang, Qing-Li Shang, Jing-Xue Ma, Shu-Xia Liu, Cai-Xia Wang, and Cheng Ma
- Subjects
choroidal neovascularization ,complement factor b ,short hairpin rna ,membrane attack complex ,vascular endothelial growth factor ,Ophthalmology ,RE1-994 - Abstract
AIM: To evaluate whether recombinant complement factor B (CFB) short hairpin RNA (shRNA) reduces laser-induced choroidal neovascularization (CNV) in rats. METHODS: Laser-induced rat CNV model was established, and then the animals underwent fundus fluorescence angiography (FFA) and hematoxylin and eosin (HE) staining. On day 3 and 7 after photocoagulation, the expression of CFB and membrane attack complex (MAC) was detected by immunhischemistry. A recombinant CFB-shRNA plasmid was constructed. CFB and scrambled shRNA plasmids were intravenous injected into rats via the tail vein on the day of laser treatment, respectively. On day 7, the incidence of CNV was determined by FFA, and the expression of CFB and vascular endothelial growth factor (VEGF) in retinal pigment epithelium (RPE)/choroidal tissues was detected by immunhischemistry, Western blot and/or semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) in CFB and scrambled shRNA groups. The possible adverse effects of CFB-shRNA injection were assessed by transmission electron microscopy and electroretinography. RESULTS: FFA and HE results indicated that a laser-induced rat CNV model was successfully established on day 7 after photocoagulation. The expression of CFB and MAC was extremely weak in normal retina and choroid, and increased on day 3 after photocoagulation. However, it started to reduce on day 7. CFB shRNA plasmid was successfully constructed and induced CFB knockdown in the retinal and choroidal tissues. FFA showed CFB knockdown significantly inhibited incidence of CNV in rats. Moreover, CFB knockdown significantly inhibited the expression of VEGF in RPE/choroidal tissues. CFB shRNA caused no obvious side effects in eyes. CONCLUSION: CFB knockdown significantly inhibits the formation and development of CNV in vivo through reducing the expression of VEGF, which is a potential therapy target. The alternative pathway of complement activation plays an important role in CNV formation.
- Published
- 2020
- Full Text
- View/download PDF
45. Research on function optimization problem based on artificial bee colony algorithm.
- Author
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Shu-xia, Li and Jie-sheng, Wang
- Published
- 2015
- Full Text
- View/download PDF
46. Analysis of Machine Learning Techniques for Heart Failure Readmissions.
- Author
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Mortazavi, Bobak J., Downing, Nicholas S., Bucholz, Emily M., Dharmarajan, Kumar, Manhapra, Ajay, Shu-Xia Li, Negahban, Sahand N., Krumholz, Harlan M., and Li, Shu-Xia
- Subjects
HEART failure ,HEART failure treatment ,ALGORITHMS ,CHAOS theory ,CLINICAL trials ,COMPARATIVE studies ,DATABASES ,RESEARCH methodology ,MEDICAL cooperation ,META-analysis ,RESEARCH ,RESEARCH evaluation ,RESEARCH funding ,RISK assessment ,STATISTICAL sampling ,TELEMEDICINE ,TIME ,DATA mining ,LOGISTIC regression analysis ,EVALUATION research ,RANDOMIZED controlled trials ,PATIENT readmissions ,DIAGNOSIS - Abstract
Background: The current ability to predict readmissions in patients with heart failure is modest at best. It is unclear whether machine learning techniques that address higher dimensional, nonlinear relationships among variables would enhance prediction. We sought to compare the effectiveness of several machine learning algorithms for predicting readmissions.Methods and Results: Using data from the Telemonitoring to Improve Heart Failure Outcomes trial, we compared the effectiveness of random forests, boosting, random forests combined hierarchically with support vector machines or logistic regression (LR), and Poisson regression against traditional LR to predict 30- and 180-day all-cause readmissions and readmissions because of heart failure. We randomly selected 50% of patients for a derivation set, and a validation set comprised the remaining patients, validated using 100 bootstrapped iterations. We compared C statistics for discrimination and distributions of observed outcomes in risk deciles for predictive range. In 30-day all-cause readmission prediction, the best performing machine learning model, random forests, provided a 17.8% improvement over LR (mean C statistics, 0.628 and 0.533, respectively). For readmissions because of heart failure, boosting improved the C statistic by 24.9% over LR (mean C statistic 0.678 and 0.543, respectively). For 30-day all-cause readmission, the observed readmission rates in the lowest and highest deciles of predicted risk with random forests (7.8% and 26.2%, respectively) showed a much wider separation than LR (14.2% and 16.4%, respectively).Conclusions: Machine learning methods improved the prediction of readmission after hospitalization for heart failure compared with LR and provided the greatest predictive range in observed readmission rates. [ABSTRACT FROM AUTHOR]- Published
- 2016
- Full Text
- View/download PDF
47. Upregulation of circFLNA contributes to laryngeal squamous cell carcinoma migration by circFLNA–miR-486-3p-FLNA axis
- Author
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Jian-Xing Wang, Yan Liu, Xin-Ju Jia, Shu-Xia Liu, Jin-Hui Dong, Xiu-Min Ren, Ou Xu, Hai-Zhong Zhang, Hui-Jun Duan, and Chun-Guang Shan
- Subjects
Laryngeal squamous cell carcinoma ,FLNA ,circRNAs ,Migration ,miRNA ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 ,Cytology ,QH573-671 - Abstract
Abstract Background Accumulating evidence shows that circular RNAs (circRNAs) plays vital roles in tumor progression. However, the biological functions of circRNAs in laryngeal squamous cell carcinoma (LSCC) metastasis is still unclear. Methods qRT-PCR was used to detect circFLNA, miRNAs and FLNA mRNA expression. Transwell assay and western blot were performed to evaluate cell migration ability and to detect FLNA, MMP2 and MLK1 protein expression, respectively. RNA pull-down analysis was used to find the binding-miRNAs of circFLNA. Luciferase reporter assay was used to examine the effect of circFLNA on miRNAs and miR-486-3p on FLNA expression. Results In this study, we confirmed that a Filamin A (FLNA)-derived hsa_circ_0092012 known as circFLNA, was upregulated in LSCC, and the higher expression of circFLNA was correlated with LSCC lymph node metastasis. Increased circFLNA facilitates LSCC cell migration ability through upregulating FLNA and MMP2 protein expression. Mechanistically, we find that circFLNA sponges miR-486-3p in LSCC cells, relieving miR-486-3p-induced repression of FLNA which promotes LSCC cell migration. Accordingly, FLNA mRNA is overexpressed in LSCC tissues and a higher FLNA level is correlated with poor survival. Dysregulation of the circFLNA/miR-486-3p/FLNA regulatory pathway contributes to LSCC migration. Conclusions In summary, our study sheds light on the regulatory mechanism of circFLNA in LSCC migration via sponging miR‐486-3p, which downregulates the FLNA protein expression. Targeting circFLNA/miR-486-3p/FLAN axis provides a potential therapeutic target for aggressive LSCC.
- Published
- 2019
- Full Text
- View/download PDF
48. Hierarchical Biocarbons with Controlled Micropores and Mesopores Derived from Kapok Fruit Peels for High-Performance Supercapacitor Electrodes
- Author
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Shu-Xia Liang, Fang-Fang Duan, Qiu-Feng Lü, and Haijun Yang
- Subjects
Chemistry ,QD1-999 - Published
- 2019
- Full Text
- View/download PDF
49. Computation of renameable horn backdoors for quantified boolean formulas.
- Author
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Jun-Cheng Yang, Shu-Xia Li, and Jin-Yan Wang
- Published
- 2010
- Full Text
- View/download PDF
50. Hospital Variation in the Use of Noninvasive Cardiac Imaging and Its Association With Downstream Testing, Interventions, and Outcomes.
- Author
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Safavi, Kyan C., Shu-Xia Li, Kumar, Dharmarajan, Venkatesh, Arjun K., Strait, Kelly M., Haiqun Lin, Lowe, Timothy J., Fazel, Reza, Nallamothu, Brahmajee K., and Krumholz, Harlan M.
- Published
- 2014
- Full Text
- View/download PDF
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