559 results on '"Zhi-Gang Yang"'
Search Results
52. The additive effects of kidney dysfunction on left ventricular function and strain in type 2 diabetes mellitus patients verified by cardiac magnetic resonance imaging
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Yi Zhang, Jin Wang, Yan Ren, Wei-feng Yan, Li Jiang, Yuan Li, and Zhi-gang Yang
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Type 2 diabetes mellitus ,Chronic kidney disease ,Left ventricular ,Strain ,Magnetic resonance imaging ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Patients with type 2 diabetes mellitus (T2DM) are susceptible to coexisted with chronic kidney disease (CKD), which may increase cardiovascular mortality in these patients. The present study aimed to verify whether CKD aggravates the deterioration of left ventricular (LV) myocardial strain in T2DM patients and to explore the risk factors associated with LV strain. Materials and methods In total, 105 T2DM patients and 52 healthy individuals were included and underwent cardiac magnetic resonance examination. Patients were divided into the following two groups: T2DM with CKD (n = 33) and T2DM without CKD (n = 72). The baseline clinical and biochemical indices were obtained from hospital records before the cardiac magnetic resonance scan. Cine sequences, including long-axis views (2-chamber and 4-chamber) and short-axis views, were acquired. LV function and global strain parameters were measured based on cine sequences and compared among three groups. Pearson’s analysis was performed to investigate the correlation between LV strain parameters and clinical indices. Multiple linear regression analysis was used to identify the independent indicators of LV strain. Results Compared with normal controls, T2DM patients without CKD had a significantly decreased magnitude of peak strain (PS; radial), peak systolic strain rate (radial), and peak diastolic strain rate (radial and circumferential) (all P
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- 2021
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53. Piezoelectric drive hydraulic amplification flexible Braille contact device design and experiment
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Xiao-chao Tian, Hu Wang, Zhi-cong Wang, Jun Hou, Jia-ying Lin, Jin-long Liu, Shen-fang Li, and Zhi-gang Yang
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Physics ,QC1-999 - Abstract
The purpose of this paper is to use the principle of hydraulic amplification and design a piezoelectric drive-based hydraulically amplified flexible Braille contact device with good performance output. In this paper, the structure and working principle of the Braille contact device are described, and the theoretical analysis and parametric design of the hydraulic amplification unit are carried out. The influence relationship between the displacement amplification and diameter and height of the reservoir are obtained by using MATLAB simulation analysis, whereas the output displacement of the piezoelectric vibrator and the flexible film under different driving voltages is measured by using a laser micrometer. Subsequently, the experiments are consistent with the theoretical analysis, and the correctness of the theoretical analysis is verified. Finally, experimental tests of the system are implemented. The results suggest that the displacement amplification ratio is 4.16, and the contact displacement formed by the flexible film is 0.226 mm. Thus, the requirements of the touch sensitivity standard for the blind are satisfied when the reservoir diameter is 20 mm and the reservoir height is 3 mm. The filling water is 7.5 ml, and the resonance frequency is 317.5 Hz. This study proves that constructing a Braille bump device in this way is feasible as well as effective.
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- 2022
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54. Additive Effects of Obesity on Myocardial Microcirculation and Left Ventricular Deformation in Essential Hypertension: A Contrast-Enhanced Cardiac Magnetic Resonance Imaging Study
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Pei-Lun Han, Xue-Ming Li, Li Jiang, Wei-Feng Yan, Ying-Kun Guo, Yuan Li, Kang Li, and Zhi-Gang Yang
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hypertension ,obesity ,left ventricular deformation ,myocardial perfusion ,magnetic resonance imaging ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
ObjectiveThe combination of hypertension and obesity is a major cause of cardiovascular risk, and microvascular changes and subclinical dysfunction should be considered to illustrate the underlying mechanisms and early identification, thereby developing targeted therapies. This study aims to explore the effect of obesity on myocardial microcirculation and left ventricular (LV) deformation in hypertensive patients by cardiac magnetic resonance (CMR).MethodsThis study comprised 101 hypertensive patients, including 54 subjects with a body mass index (BMI) of 18.5–24.9 kg/m2 and 47 subjects with a BMI ≥25 kg/m2, as well as 55 age- and sex-matched controls with a BMI of 18.5–24.9 kg/m2. Myocardial perfusion indicators [upslope, time to maximum signal intensity (TTM), maximum signal intensity (Max SI)] and LV strains [radial, circumferential, and longitudinal global peak strain (PS), peak systolic strain rate (PSSR), and peak diastolic strain rate (PDSR)] were measured.ResultsUpslope was numerically increased in obese patients but statistically decreased in non-obese patients compared with controls. Longitudinal PS deteriorated significantly and gradually from controls to non-obese and obese hypertensive patients. Longitudinal PSSR and PDSR were significantly decreased in obese hypertensive patients compared with the other two groups. BMI was associated with upslope (β = −0.136, P < 0.001), Max SI (β = −0.922, P < 0.001), longitudinal PSSR (β = 0.018, P < 0.001), and PDSR (β = −0.024, P = 0.001). Myocardial perfusion was independently associated with longitudinal PSSR (TTM: β = 0.003, P = 0.017) and longitudinal PDSR (upslope: β = 0.067, P = 0.020) in hypertension.ConclusionObesity had adverse effects on microvascular changes and subclinical LV dysfunction in hypertension, and BMI was independently associated with both myocardial perfusion and LV deformation. Impaired myocardial perfusion was independently associated with subclinical LV dysfunction in hypertension.
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- 2022
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55. A novel prognostic model predicting the long-term cancer-specific survival for patients with hypopharyngeal squamous cell carcinoma
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Xin Tang, Tong Pang, Wei-feng Yan, Wen-lei Qian, You-ling Gong, and Zhi-gang Yang
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Head and neck cancer ,Hypopharyngeal squamous cell carcinoma ,Cancer-specific survival ,Nomogram ,Prognostic model ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Hypopharyngeal squamous cell carcinoma (HSCC) is a rare type of head and neck cancer with poor prognosis. However, till now, there is still no model predicting the survival outcomes for HSCC patients. We aim to develop a novel nomogram predicting the long-term cancer-specific survival (CSS) for patients with HSCC and establish a prognostic classification system. Methods Data of 2021 eligible HSCC patients were retrieved from the Surveillance, Epidemiology and End Results database between 2010 and 2015. We randomly split the whole cases (ratio: 7:3) into the training and the validation cohort. Cox regression as well as the Least absolute shrinkage and selection operator (LASSO) COX were used to select significant predictors of CSS. Based on the beta-value of these predictors, a novel nomogram was built. The concordance index (C-index), the calibration curve and the decision curve analysis (DCA) were utilized for the model validation and evaluation using the validation cohort. Results In total, cancer-specific death occurred in 974/2021 (48.2%) patients. LASSO COX indicated that age, race, T stage, N stage, M stage, surgery, radiotherapy and chemotherapy are significant prognosticators of CSS. A prognostic model based on these factors was constructed and visually presented as nomogram. The C-index of the model was 0.764, indicating great predictive accuracy. Additionally, DCA and calibration curves also demonstrated that the nomogram had good clinical effect and satisfactory consistency between the predictive CSS and actual observation. Furthermore, we developed a prognostic classification system that divides HSCC patients into three groups with different prognosis. The median CSS for HSCC patients in the favorable, intermediate and poor prognosis group was not reached, 39.0-Mo and 10.0-Mo, respectively (p
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- 2020
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56. The additive effects of type 2 diabetes mellitus on left ventricular deformation and myocardial perfusion in essential hypertension: a 3.0 T cardiac magnetic resonance study
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Xue-Ming Li, Li Jiang, Ying-Kun Guo, Yan Ren, Pei-Lun Han, Li-Qing Peng, Rui Shi, Wei-Feng Yan, and Zhi-Gang Yang
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Hypertension ,Type 2 diabetes mellitus ,Left ventricular strains ,Perfusion ,Magnetic resonance imaging ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Type 2 diabetes mellitus (T2DM) increases the risks of heart failure and mortality in patients with hypertension, however the underlying mechanism is unclear. This study aims to investigate the impact of coexisting T2DM on left ventricular (LV) deformation and myocardial perfusion in hypertensive individuals. Materials and methods Seventy hypertensive patients without T2DM [HTN(T2DM−)], forty patients with T2DM [HTN(T2DM+)] and 37 age- and sex-matched controls underwent cardiac magnetic resonance examination. Left ventricular (LV) myocardial strains, including global radial (GRPS), circumferential (GCPS) and longitudinal peak strain (GLPS), and resting myocardial perfusion indices, including upslope, time to maximum signal intensity (TTM), and max signal intensity (MaxSI), were measured and compared among groups by analysis of covariance after adjusting for age, sex, body mass index (BMI) and heart rate followed by Bonferroni’s post hoc test. Backwards stepwise multivariable linear regression analyses were performed to determine the effects of T2DM on LV strains and myocardial perfusion indices in patients with hypertension. Results Both GRPS and GLPS deteriorated significantly from controls, through HTN(T2DM−), to HTN(T2DM+) group; GCPS in HTN(T2DM+) group was lower than those in both HTN(T2DM−) and control groups. Compared with controls, HTN(T2DM−) group showed higher myocardial perfusion, and HTN(T2DM+) group exhibited lower perfusion than HTN(T2DM−) group and controls. Multiple regression analyses considering covariates of systolic blood pressure, age, sex, BMI, heart rate, smoking, indexed LV mass and eGFR demonstrated that T2DM was independently associated with LV strains (GRPS: p = 0.002, model R 2= 0.383; GCPS: p
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- 2020
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57. Aneurysmal subarachnoid hemorrhage with neurogenic pulmonary edema: one case report
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Xin ZHANG and Zhi⁃gang YANG
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intracranial aneurysm ,subarachnoid hemorrhage ,postoperative complications ,pulmonary edema ,respiration, artificial ,case reports ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
DOI:10.3969/j.issn.1672⁃6731.2020.08.010
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- 2020
58. The additive effects of obesity on myocardial microcirculation in diabetic individuals: a cardiac magnetic resonance first-pass perfusion study
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Li Jiang, Ke Shi, Ying-kun Guo, Yan Ren, Zhen-lin Li, Chun-chao Xia, Lei Li, Xi Liu, Lin-jun Xie, Yue Gao, Meng-ting Shen, Ming-yan Deng, and Zhi-gang Yang
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Body mass index ,Cardiac magnetic resonance first-pass perfusion imaging ,Myocardial microvascular function ,Obesity ,Type 2 diabetes mellitus ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background The microvascular effects of obesity should be considered in diabetic individuals for elucidating underlying mechanisms and developing targeted therapies. This study aims to determine the effect of obesity on myocardial microvascular function in type 2 diabetes mellitus (T2DM) patients using cardiac magnetic resonance (CMR) first-pass perfusion imaging and assessed significant risk factors for microvascular dysfunction. Materials and methods Between September 2016 and May 2018, 120 patients with T2DM (45.8% women [55 of 120]; mean age, 56.45 ± 11.97 years) and 79 controls (44.3% women [35 of 79]; mean age, 54.50 ± 7.79 years) with different body mass index (BMI) scales were prospectively enrolled and underwent CMR examination. CMR-derived perfusion parameters, including upslope, time to maximum signal intensity (TTM), maximum signal intensity (MaxSI), MaxSI (-baseline), and SI (baseline), and T2DM related risk factors were analyzed among groups/subgroups both in T2DM patients and controls. Univariable and multivariable linear and logistic regression analyses were performed to assess the potential additive effect of obesity on microvascular dysfunction in diabetic individuals. Results Compared with controls with comparable BMIs, patients with T2DM showed reduced upslope and MaxSI and increased TTM. For both T2DM and control subgroups, perfusion function gradually declined with increasing BMI, which was confirmed by all perfusion parameters, except for TTM (all P
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- 2020
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59. Metabolic syndrome and myocardium steatosis in subclinical type 2 diabetes mellitus: a 1H-magnetic resonance spectroscopy study
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Yue Gao, Yan Ren, Ying-kun Guo, Xi Liu, Lin-jun Xie, Li Jiang, Meng-ting Shen, Ming-yan Deng, and Zhi-gang Yang
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Myocardial steatosis ,Metabolic syndrome ,Subclinical myocardial dysfunction ,1H-magnetic resonance spectroscopy ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Metabolic syndrome (MetS) is a cluster of metabolic abnormalities that collectively cause an increased risk of type 2 diabetes mellitus (T2DM) and nonatherosclerotic cardiovascular disease. This study aimed to evaluate the role of myocardial steatosis in T2DM patients with or without MetS, as well as the relationship between subclinical left ventricular (LV) myocardial dysfunction and myocardial steatosis. Methods and materials We recruited 53 T2DM patients and 20 healthy controls underwent cardiac magnetic resonance examination. All T2DM patients were subdivide into two group: MetS group and non-MetS. LV deformation, perfusion parameters and myocardial triglyceride (TG) content were measured and compared among these three groups. Pearson’s and Spearman analysis were performed to investigate the correlation between LV cardiac parameters and myocardial steatosis. The receiver operating characteristic curve (ROC) was performed to illustrate the relationship between myocardial steatosis and LV subclinical myocardial dysfunction. Results An increase in myocardial TG content was found in the MetS group compared with that in the other groups (MetS vs. non-MetS: 1.54 ± 0.63% vs. 1.16 ± 0.45%; MetS vs. normal: 1.54 ± 0.63% vs. 0.61 ± 0.22%; all p
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- 2020
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60. RETRACTED ARTICLE: Prognostic value of heart failure in hemodialysis-dependent end-stage renal disease patients with myocardial fibrosis quantification by extracellular volume on cardiac magnetic resonance imaging
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Hua-yan Xu, Zhi-gang Yang, Yi Zhang, Wan-lin Peng, Chun-chao Xia, Zhen-lin Li, Yong He, Rong Xu, Li Rao, Ying Peng, Yu-ming Li, Hong-ling Gao, and Ying-kun Guo
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End stage renal disease ,Myocardial fibrosis ,Cardiac magnetic resonance ,T1 mapping ,ECV ,Heart failure ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background End-stage renal disease (ESRD) patients are at high cardiovascular risk, and myocardial fibrosis (MF) accounts for most of their cardiac events. The purpose of this study is to investigate the prognostic value and risk stratification of MF as measured by extracellular volume (ECV) on cardiac magnetic resonance (CMR) for heart failure (HF) in patients with hemodialysis-dependent ESRD. Methods Sixty-six hemodialysis ESRD patients and 25 matched healthy volunteers were prospectively enrolled and underwent CMR to quantify multiple parameters of MF by T1 mapping and late gadolinium enhancement (LGE). All ESRD patients were followed up for 11–30 months, and the end-point met the 2016 ESC guidelines for the definition of HF. Results Over a median follow-up of 18 months (range 11–30 months), there were 26 (39.39%) guideline-diagnosed HF patients in the entire cohort of ESRD subjects. The native T1 value was elongated, and ECV was enlarged in the HF cohort relative to the non-HF cohort and normal controls (native T1, 1360.10 ± 50.14 ms, 1319.39 ± 55.44 ms and 1276.35 ± 56.56 ms; ECV, 35.42 ± 4.42%, 31.85 ± 3.01% and 26.97 ± 1.87%; all p
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- 2020
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61. Prognostic value of dual-source computed tomography (DSCT) angiography characteristics in anomalous coronary artery from the opposite sinus (ACAOS) patients: a large-scale retrospective study
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Kai-yue Diao, Qin Zhao, Yue Gao, Ke Shi, Min Ma, Hua-yan Xu, Ying-kun Guo, and Zhi-gang Yang
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Coronary vessel anomalies ,Computed tomography angiography ,Congenital abnormalities ,Diagnosis ,Prognostic factor ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Most reported cases of right anomalous coronary artery from the opposite sinus (R-ACAOS) have benign clinical outcomes. However, patients with left ACAOS (L-ACAOS) and some of the patients with R-ACAOS are more at risk for arrhythmias and sudden cardiac death, which remains a major concern. Here we report the prevalence and anatomical features of ACAOS patients. Moreover, we explore the high-risk morphological signs and evaluate their mid-term prognostic value in R-ACAOS patients without surgical intervention. Methods Data from coronary computed tomography angiography (CTA) of 30,593 patients, pertaining to a single center over 5 consecutive years, were retrospectively analyzed. The image analysis included stenosis severity ranking and high-risk anatomy evaluation, based on the commercially available image post-processing software OsirX. Patients with R-ACAOS and without evidence of coronary atherosclerosis (CAD) were followed-up, with recording of the cardiovascular clinical events. Cox regression analysis was performed to identify the potential anatomical risk factors of cardiovascular clinical events for non-CAD R-ACAOS patients, using R project. Results The prevalence of ACAOS in the study population was 0.69% (211/30593). Significant differences were found between patients with mild ( 50%) stenosis, in terms of height-to-weight ratio (HW ratio), take-off angle, and proximal stenosis length. A total of 54 cardiovascular clinical events were observed among 108 non-CAD R-ACAOS patients and an average follow-up of 27.8 ± 18.7 months. Among those patients’ anatomical features, stenosis severity was the main risk factor for cardiovascular clinical events during the mid-term follow-up, with a risk ratio of 4.14 (95% CI: 1.78 to 9.63, P
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- 2020
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62. Association of myocardial fibrosis detected by late gadolinium-enhanced MRI with clinical outcomes in patients with diabetes: a systematic review and meta-analysis
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Hang Fu, Hui Liu, Hong Li, Lu Zhang, Rong Xu, Zhi-gang Yang, Jia-rong Wang, Hua-yan Xu, Ling-jun Xie, Meng-xi Yang, Ling-yi Wen, and Ying-kun Guo
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Medicine - Published
- 2022
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63. Rationale, design, and baseline characteristics of Chinese registry in early detection and risk stratification of coronary plaques (C-STRAT) study
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Jun-Jie Yang, Dong-Kai Shan, Lei Xu, Jun-Fu Liang, Zhao-Qian Wang, Mei Zhang, Min Li, Wen-Jie Yang, Jian-Rong Xu, Yong-Gao Zhang, Li-Ming Xia, Li-Hua Wang, Hong-Jie Hu, Zhi-Gang Yang, Tao Li, Qi Tian, Xu-Dong Lyu, Yun-Dai Chen, and Ning-Ning Wang
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Medicine - Published
- 2021
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64. Effect of Smoking on Coronary Artery Plaques in Type 2 Diabetes Mellitus: Evaluation With Coronary Computed Tomography Angiography
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Yu Jiang, Tong Pang, Rui Shi, Wen-lei Qian, Wei-feng Yan, Yuan Li, and Zhi-gang Yang
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type 2 diabetes mellitus ,smoking ,coronary computed tomographic angiography ,coronary artery plaques ,atherosclerosis ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
BackgroundThe effect of smoking on coronary artery plaques examined by coronary computed tomography angiography (CCTA) in type 2 diabetes mellitus (DM) patients is not fully understood. This study explored the effect of smoking on coronary artery plaques by comparing the characteristics of plaques between diabetes patients with and without a smoking history and among those with different smoking durations.Materials and MethodsIn total, 1058 DM patients found to have coronary plaques on CCTA were categorized into the smoker (n=448) and nonsmoker groups (n=610). Smokers were stratified by smoking duration [≤20 years (n=115), 20~40 years (n=233) and >40 years (n=100)]. The plaque types, luminal stenosis [obstructive (40 years had higher OR of any mixed plaques (OR=2.623 and 3.052, respectively; Ps40 years had a higher OR of SIS≥4 (OR=1.916, P=0.034).ConclusionSmoking is independently associated with the presence of noncalcified, obstructive, and more extensive coronary artery plaques in diabetes patients, and a longer smoking duration is significantly associated with a higher risk of mixed, obstructive, and more extensive plaques.
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- 2021
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65. Machine Learning-Based CT Radiomics Analysis for Prognostic Prediction in Metastatic Non-Small Cell Lung Cancer Patients With EGFR-T790M Mutation Receiving Third-Generation EGFR-TKI Osimertinib Treatment
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Xin Tang, Yuan Li, Wei-feng Yan, Wen-lei Qian, Tong Pang, You-ling Gong, and Zhi-gang Yang
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lung cancer ,EGFR-T790M ,osimertinib ,radiomics ,prognostic prediction ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background and PurposeAs a third-generation EGFR tyrosine kinase inhibitor (TKI), osimertinib is approved for treating advanced non-small cell lung cancer (NSCLC) patients with EGFR-T790M mutation after progression on first- or second-generation EGFR-TKIs such as gefitinib, erlotinib and afatinib. We aim at exploring the feasibility and effectiveness of using radiomic features from chest CT scan to predict the prognosis of metastatic non-small cell lung cancer (NSCLC) patients with EGFR-T790M mutation receiving second-line osimertinib therapy.MethodsContrast-enhanced and unenhanced chest CT images before osimertinib treatment were collected from 201 and 273 metastatic NSCLC patients with EGFR-T790M mutation, respectively. Radiomic features were extracted from the volume of interest. LASSO regression was used to preliminarily evaluate the prognostic values of different radiomic features. We then performed machine learning-based analyses including random forest (RF), support vector machine (SVM), stepwise regression (SR) and LASSO regression with 5-fold cross-validation (CV) to establish the optimal radiomic model for predicting the progression-free survival (PFS) of osimertinib treatment. Finally, a combined clinical-radiomic model was developed and validated using the concordance index (C-index), decision-curve analysis (DCA) and calibration curve analysis.ResultsDisease progression occurred in 174/273 (63.7%) cases. CT morphological features had no ability in predicting patients’ prognosis in osimertinib treatment. Univariate COX regression followed by LASSO regression analyses identified 23 and 6 radiomic features from the contrast-enhanced and unenhanced CT with prognostic value, respectively. The 23 contrast-enhanced radiomic features were further used to construct radiomic models using different machine learning strategies. Radiomic model built by SR exhibited superior predictive accuracy than RF, SVR or LASSO model (mean C-index of the 5-fold CV: 0.660 vs. 0.560 vs. 0.598 vs. 0.590). Adding the SR radiomic model to the clinical model could remarkably strengthen the C-index of the latter from 0.672 to 0.755. DCA and calibration curve analyses also demonstrated good performance of the combined clinical-radiomic model.ConclusionsRadiomic features extracted from the contrast-enhanced chest CT could be used to evaluate metastatic NSCLC patients’ prognosis in osimertinib treatment. Prognostic models combing both radiomic features and clinical factors had a great performance in predicting patients’ outcomes.
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- 2021
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66. Design and test of a piezoelectric micropump based on hydraulic amplification
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Xiao-chao Tian, Hai-gang Wang, Hu Wang, Zhi-cong Wang, Yu-ze Sun, Jin-zhi Zhu, Jian Zhao, Si-da Zhang, and Zhi-gang Yang
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Physics ,QC1-999 - Abstract
To solve the problem of the small deformation of piezoelectric vibrators and improve the overall performance of piezoelectric micro-pumps, a flexible-diaphragm piezoelectric micropump is designed based on hydraulic amplification. The micropump uses a piezoelectric vibrator to provide its driving force, and fluid is delivered by driving the liquid to amplify the displacement of the piezoelectric vibrator. First, the working principle of the piezoelectric micropump is analyzed, and then theoretical analysis and displacement output tests of the hydraulic amplifier unit are carried out. The test results are consistent with those of the theoretical analysis, and the amplification factor of the hydraulic amplifier unit is 3.29. Finally, prototypes are produced and an experimental platform is built for testing. The results indicate that the best-performing piezoelectric micropump has a self-priming height of 1200 mm, an output pressure of 22.16 kPa, and an output flow of 23.18 ml/min. Compared with an ordinary piezoelectric pump, the overall performance of the piezoelectric micropump is greatly improved.
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- 2021
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67. Serial coronary computed tomography angiography-verified coronary plaque progression: comparison of stented patients with or without diabetes
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Rui Shi, Ke Shi, Zhi-gang Yang, Ying-kun Guo, Kai-yue Diao, Yue Gao, Yi Zhang, and Shan Huang
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Type 2 diabetes mellitus ,Coronary artery computed tomography ,Percutaneous coronary intervention ,Coronary plaques ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Patients with Diabetes mellitus (DM) are susceptible to coronary artery disease (CAD). However, the impact of DM on plaque progression in the non-stented segments of stent-implanted patients has been rarely reported. This study aimed to evaluate the impact of DM on the prevalence, characteristics and severity of coronary computed tomography angiography (CCTA) verified plaque progression in stented patients. A comparison between diabetic and non-diabetic patients was performed. Methods A total of 98 patients who underwent clinically indicated serial CCTAs arranged within 1 month before and at least 6 months after percutaneous coronary intervention (PCI) were consecutively included. All the subjects were categorized into diabetic group (n = 36) and non-diabetic groups (n = 62). Coronary stenosis extent scores, segment involvement scores (SIS), segment stenosis scores (SSS) at baseline and follow-up CCTA were quantitatively assessed. The prevalence, characteristics and severity of plaque progression was evaluated blindly to the clinical data and compared between the groups. Results During the median 1.5 year follow up, a larger number of patients (72.2% vs 40.3%, P = 0.002), more non-stented vessels (55.7% vs 23.2%, P
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- 2019
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68. Aeroacoustic Optimization Design of the Middle and Upper Part of Pantograph
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Jing Guo, Xiao-Ming Tan, Zhi-Gang Yang, Yu-Qi Xue, Ya-Nan Shen, and Hao-Wei Wang
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pantograph ,aerodynamic noise ,large eddy simulation ,optimal design ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The pantograph is the main noise source of high-speed trains, of which the middle and upper parts of the pantograph account for about 50% of the whole noise energy. Taking CRH380BL pantograph as the basic prototype, three aerodynamic noise reduction measures of opening, slotting, and airfoil are introduced to build a new pantograph, and their aeroacoustic performances are comprehensively investigated through large eddy simulation (LES) and Ffowcs Williams–Hawkings (FW-H) equation method. The research results show that the open upper and lower arms (ULA) can reduce the downstream vorticity intensity and vortex structure scale, which in turn reduces the noise source intensity, thus reducing their radiated noise by approximately 1.1 dBA. The slotted ULA reduce the size of the rear vortex structure but increase the vorticity intensity, so it is difficult to effectively control their radiated noise. The airfoil bow head reduces the vorticity intensity and vortex structure scale behind it, and avoids periodic vortex shedding, thereby reducing its noise source intensity, thus reducing its radiated noise by about 1.2 dBA.
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- 2022
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69. Corrosion–Resistance Mechanism of TC4 Titanium Alloy under Different Stress-Loading Conditions
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Xin-Yu Wang, Shi-Dong Zhu, Zhi-Gang Yang, Cheng-Da Wang, Ning Wang, Yong-Qiang Zhang, and Feng-Ling Yu
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TC4 titanium alloy ,stress load ,electrochemical test ,pitting mechanism ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Titanium alloys have now become the first choice of tubing material used in the harsh oil- and gas-exploitation environment, while the interaction of force and medium is a serious threat to the safety and reliability of titanium alloy in service. In this paper, different stresses were applied to TC4 titanium alloy by four-point bending stress fixture, and the corrosion behavior of TC4 titanium alloy was studied by high-temperature and high-pressure simulation experiments and electrochemical techniques, and the microscopic morphologies and chemical composition of the surface film layer on the specimen were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), to reveal the corrosion-resistance mechanism of TC4 titanium alloy under different stress-loading conditions. The results showed that the pits appeared on the specimens loaded with elastic stress, but the degree of pitting corrosion was still lighter, and the surface film layer showed n-type semiconductor properties with cation selective permeability. While the pits on the specimens loaded with plastic stress were deeper and wider in size, and the semiconductor type of the surface film layer changed to p-type, it was easier for anions such as Cl− and CO32− to adsorb on, destroy, and pass through the protective film and then to contact with the matrix, resulting in a decrease in corrosion resistance of TC4 titanium alloy.
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- 2022
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70. The Prognostic Value of Radiomics Features Extracted From Computed Tomography in Patients With Localized Clear Cell Renal Cell Carcinoma After Nephrectomy
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Xin Tang, Tong Pang, Wei-feng Yan, Wen-lei Qian, You-ling Gong, and Zhi-gang Yang
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radiomics ,computed tomography ,clear cell renal cell carcinoma ,prognosis ,predictive model ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background and purposeRadiomics is an emerging field of quantitative imaging. The prognostic value of radiomics analysis in patients with localized clear cell renal cell carcinoma (ccRCC) after nephrectomy remains unknown.MethodsComputed tomography images of 167 eligible cases were obtained from the Cancer Imaging Archive database. Radiomics features were extracted from the region of interest contoured manually for each patient. Hierarchical clustering was performed to divide patients into distinct groups. Prognostic assessments were performed by Kaplan–Meier curves, COX regression, and least absolute shrinkage and selection operator COX regression. Besides, transcriptome mRNA data were also included in the prognostic analyses. Endpoints were overall survival (OS) and disease-free survival (DFS). Concordance index (C-index), decision curve analysis and calibration curves with 1,000 bootstrapping replications were used for model’s validation.ResultsHierarchical clustering groups from nephrographic features and mRNA can divide patients into different prognostic groups while clustering groups from corticomedullary or unenhanced phase couldn’t distinguish patients’ prognosis. In multivariate analyses, 11 OS-predicting and eight DFS-predicting features were identified in nephrographic phase. Similarly, seven OS-predictors and seven DFS-predictors were confirmed in mRNA data. In contrast, limited prognostic features were found in corticomedullary (two OS-predictor and two DFS-predictors) and unenhanced phase (one OS-predictors and two DFS-predictors). Prognostic models combining both nephrographic features and mRNA showed improved C-index than any model alone (C-index: 0.927 and 0.879 for OS- and DFS-predicting, respectively). In addition, decision curves and calibration curves also revealed the great performance of the novel models.ConclusionWe firstly investigated the prognostic significance of preoperative radiomics signatures in ccRCC patients. Radiomics features obtained from nephrographic phase had stronger predictive ability than features from corticomedullary or unenhanced phase. Multi-omics models combining radiomics and transcriptome data could further increase the predictive accuracy.
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- 2021
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71. Bioremediation of oily sludge by solid complex bacterial agent with a combined two-step process
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Cong-Yu Ke, Fang-Ling Qin, Zhi-Gang Yang, Jun Sha, Wu-Juan Sun, Jun-Feng Hui, Qun-Zheng Zhang, and Xun-Li Zhang
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Bioremediation ,Oily sludge ,Solid complex bacterial agent ,Two-step combined treatment ,Environmental pollution ,TD172-193.5 ,Environmental sciences ,GE1-350 - Abstract
In the present research, a bioremediation process was developed using solid complex bacterial agents (SCBA) through a combined two-step biodegradation process. Four isolated strains showed high efficiency for the degradation of total petroleum hydrocarbons (TPH) and the reduction of COD of the oily sludge, at 96.6% and 92.6%, respectively. The mixed strains together with bran prepared in form of SCBA exhibited improved performance compared to individual strains, all of which had an optimal temperature of around 35 °C. The use of SCBA provided advantages over commonly used liquid media for storage and transportation. The two-step process, consisting of firstly biosurfactant-assisted oil recovery and secondly biodegradation of the remaining TPH with SCBA, demonstrated the capability for treating oily sludge with high TPH content (>10 wt%) and short process period (60 days). The large-scale (5 tons oily sludge) field test, achieving a TPH removal efficiency of 93.8% and COD reduction of 91.5%, respectively, confirmed the feasibility and superiority of the technology for industrial applications.
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- 2021
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72. Anatomical characteristics of anomalous left coronary artery from the opposite sinus (left-ACAOS) and its clinical relevance: A serial coronary CT angiography study
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Pei-lun Han, Kai-yue Diao, Shan Huang, Yue Gao, Ying-kun Guo, Zhi-gang Yang, and Ning Yang
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Anomalous coronary artery ,Coronary computed tomographic angiography ,Clinical symptoms ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background: Anomalous left coronary artery from the opposite sinus (left-ACAOS) is a rare congenital heart disease. While “interarterial course” is considered as the malignant anatomic feature for these patients, a number of patients with left-ACAOS, who don’t follow the above anatomic pattern, were reported with ischemic symptoms. Purpose: This study aims to evaluate the anatomic characteristics of left-ACAOS and their clinical relevance. Methods: The coronary computed tomography angiography (CCTA) data from 44 patients with 46 left-ACAOS vessels were retrospectively included. Patients were divided into 2 groups: those with ischemic symptoms (n = 19) and those without ischemic symptoms (n = 25). Baseline clinical characteristics were recorded and the follow-up was done by telephone. CCTA images were reviewed for anomalous coronary artery, take-off angle and level, ostia morphology and grading, proximal narrowing, anomalous course and atherosclerotic plaques. Results: The prevalence of left-ACAOS was approximately 0.09% among 48, 719 consecutive patients referred for coronary CTA in our institution. Right sinus of Valsalva (RSV) was the most common origin (36/46, 78.26%). Left-ACAOS arising from right coronary artery (RCA) had narrower proximal segment (P = 0.014) and more prone to atherosclerosis (P = 0.040) than left-ACAOS arising from right sinus of Valsalva (RSV). Proximal narrowing severity (P
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- 2020
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73. Left ventricular subclinical myocardial dysfunction in uncomplicated type 2 diabetes mellitus is associated with impaired myocardial perfusion: a contrast-enhanced cardiovascular magnetic resonance study
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Xi Liu, Zhi-gang Yang, Yue Gao, Lin-jun Xie, Li Jiang, Bi-yue Hu, Kai-yue Diao, Ke Shi, Hua-yan Xu, Meng-ting Shen, Yan Ren, and Ying-kun Guo
- Subjects
Type 2 diabetes mellitus ,Cardiac magnetic resonance ,Subclinical myocardial dysfunction ,Myocardial perfusion ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Early detection of subclinical myocardial dysfunction in patients with diabetes mellitus (DM) is essential for recommending therapeutic interventions that can prevent or reverse heart failure, thereby improving the prognosis in such patients. This study aims to quantitatively evaluate left ventricular (LV) myocardial deformation and perfusion using cardiovascular magnetic resonance (CMR) imaging in patients with type 2 diabetes mellitus (T2DM), and to investigate the association between LV subclinical myocardial dysfunction and coronary microvascular perfusion. Methods We recruited 71 T2DM patients and 30 healthy individuals as controls who underwent CMR examination. The T2DM patients were subdivided into two groups, namely the newly diagnosed DM group (n = 31, patients with diabetes for ≤ 5 years) and longer-term DM group (n = 40, patients with diabetes > 5 years). LV deformation parameters, including global peak strain (PS), peak systolic strain rate, and peak diastolic strain rate (PSDR), and myocardial perfusion parameters such as upslope, time to maximum signal intensity (TTM), and max signal intensity (Max SI, were measured and compared among the three groups. Pearson’s correlation was used to evaluate the correlation between LV deformation and perfusion parameters. Results Pooled data from T2DM patients showed a decrease in global longitudinal, circumferential, and radial PDSR compared to healthy individuals, apart from lower upslope. In addition, increased TTM and reduced Max SI were found in the longer-term diabetics compared to the normal subjects (p
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- 2018
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74. Predictors of aortic dilation in patients with coarctation of the aorta: evaluation with dual-source computed tomography
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Qin Zhao, Ke Shi, Zhi-gang Yang, Kai-yue Diao, Hua-yan Xu, Xi Liu, and Ying-kun Guo
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Coarctation of the aorta ,Aortic dilation ,Aorta ,Dual-source computed tomography ,Degree of coarctation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Coarctation of aorta (CoA) may progressively develop aortic dilation at other site of the aorta and can lead to fatal aortic diseases. We aimed to evaluate the occurrence of aortic dilation and related predictors in patients with CoA using dual-source computed tomography (DSCT). Methods Fifty-three patients with CoA identified by DSCT were retrospectively reviewed. Aortic diameters were measured at six different levels and standardized as z-scores based on the square root of body surface area. Coarctation site–diaphragm ratio (CDR) was used to describe the degree of narrowing. A total of 26 patients were included in mild group (CDR > 50%) and 27 in severe group (CDR
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- 2018
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75. Computed tomography for evaluating right ventricle and pulmonary artery in pediatric tetralogy of Fallot: correlation with post-operative pulmonary regurgitation
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Yue Gao, Zhi-gang Yang, Ke Shi, Kai-yue Diao, Hua-yan Xu, and Ying-kun Guo
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Medicine ,Science - Abstract
Abstract Pulmonary regurgitation (PR) is the most common complication after tetralogy of Fallot (TOF) surgical repair, and long-term PR might result in cardiovascular events. The aim of this study was to assess the influence of pre-operative right ventricle (RV) and pulmonary artery (PA) parameters assessed by dual-source computed tomography on post-operative PR. A total of 41 TOF patients who underwent trans-valve surgical repair were retrospectively recruited. The RV and PA parameters evaluated by pre-operative DSCT were compared between the PR and non-PR groups. Our result revealed that the PA parameters (McGoon ratio, Nakata index, and LPA diameter) and RV parameters (RV length diameter and RV short diameter) all showed significant differences between the two groups (all p
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- 2018
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76. Assessment of tetralogy of Fallot–associated congenital extracardiac vascular anomalies in pediatric patients using low-dose dual-source computed tomography
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Bi-yue Hu, Ke Shi, Yu-Ping Deng, Kai-Yue Diao, Hua-Yan Xu, Rui Li, Zhi-Gang Yang, and Ying-Kun Guo
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Tetralogy of Fallot ,Dual-source computed tomography ,Pediatrics ,Radiation dosing ,Extracardiac vascular anomalies ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background To investigate the diagnostic value of dual-source computed tomography (DSCT) in the evaluation of tetralogy of Fallot (TOF)-associated extracardiac vascular abnormalities in pediatric patients compared with transthoracic echocardiography (TTE). Methods One hundred and twenty-three pediatric patients diagnosed with TOF were included in this retrospective study. All patients underwent DSCT and TTE preoperatively. All associated extracardiac vascular abnormalities and their percentages were recorded. The diagnostic performances of DSCT and TTE were compared based on the surgical results. The image quality of DSCT was rated, and the effective radiation dose (ED) was calculated. Results A total of 159 associated extracardiac vascular deformities were confirmed by surgery. Patent ductus arteriosus (36, 22.64%), right-sided aortic arch (29, 18.24%), and pulmonary valve stenosis (23, 14.47%) were the most common associated extracardiac vascular abnormalities. DSCT was superior to TTE in demonstrating associated extracardiac anomalies (diagnostic accuracy: 99.13% vs. 97.39%; sensitivity: 92.45% vs. 77.07%; specificity: 99.81% vs. 99.42%). The agreement on grading the image quality of DSCT was excellent (κ = 0.80), and the mean score of the image quality was 3.39 ± 0.50. The mean ED of DSCT was 0.86 ± 0.47 mSv. Conclusions Compared to TTE, low-dose DSCT has high diagnostic accuracy in the depiction of associated extracardiac vascular anomalies in pediatric patients with TOF, and could provide more morphological details for surgeons.
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- 2017
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77. Myocardial Deformation in Cardiac Amyloid Light-chain Amyloidosis: Assessed with 3T Cardiovascular Magnetic Resonance Feature Tracking
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Rui Li, Zhi-gang Yang, Hua-yan Xu, Ke Shi, Xi Liu, Kai-yue Diao, and Ying-kun Guo
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Medicine ,Science - Abstract
Abstract Clinically, assessment of myocardial function is essential in patients with amyloid light-chain cardiac amyloidosis (AL-CA) to predict outcome and determine therapeutic approach. The aim of this study was to investigate the feasibility of cardiovascular magnetic resonance (CMR)-derived feature tracking algorithm for assessing left ventricular (LV) myocardial deformation in AL-CA, and to determine if these abnormal myocardial deformation parameters are correlated to impaired LV myocardial microvascular dysfunction. A total of 42 AL-CA patients, including 26 with preserved systolic function and 16 with impaired LVEF, and 35 healthy controls were enrolled and underwent CMR examination. Our result indicated that AL-CA patients had significantly reduced global peak strain (PS) (longitudinal, circumferential, and radial) (all P
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- 2017
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78. Volume-time curve of cardiac magnetic resonance assessed left ventricular dysfunction in coronary artery disease patients with type 2 diabetes mellitus
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Hua-yan Xu, Zhi-gang Yang, Ying-kun Guo, Ke Shi, Xi Liu, Qin Zhang, Li Jiang, and Lin-jun Xie
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Type 2 diabetes mellitus (DM2) may induce epicardial coronary artery diseases and left ventricular myocardial damaging as well. Left ventricular dysfunction was found in DM2. In this research, we compared the left ventricular dysfunction of coronary artery disease (CAD) patients with and without type 2 diabetes mellitus as well as normal controls using the volume-time curve of cardiac magnetic resonance (CMR). Methods Sixty-one CAD patients (28 with DM2 and 33 without DM2) and 18 normal individuals were enrolled in this study. Left ventricular function parameters, including the end-diastolic and end-systolic volumes (EDV, ESV), stroke volume (SV) and ejection fraction (EF), and morphologic dimension parameters (end diastolic and systolic diameter (EDD and ESD), were measured and compared. Volume-time curve parameters, including the peak ejection rate (PER), peak ejection time (PET), peak filling rate (PFR), peak filling time from ES (PFT), peak ejection rate normalized to EDV (PER/EDV), and peak filling rate normalized to EDV (PFR/EDV), were derived automatically and compared. Results LVEF in the diabetic CAD group was markedly reduced when compared to the normal and CAD without DM2 groups (all p 166.0 msec). Higher sensitivity (87.5%) and specificity (100.0%) were obtained for PFR/EDV (criterion ≤3.7EDV/s). Conclusions Parameters that are derived from the volume-time curve on CMR, including PET, PFT and PFR/EDV, allow clinicians to predict left ventricular dysfunction in diabetic CAD subjects with a high degree of sensitivity and specificity.
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- 2017
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79. Retraction Note: Prognostic value of heart failure in hemodialysis-dependent end-stage renal disease patients with myocardial fibrosis quantification by extracellular volume on cardiac magnetic resonance imaging
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Hua-yan Xu, Zhi-gang Yang, Yi Zhang, Wan-lin Peng, Chun-chao Xia, Zhen-lin Li, Yong He, Rong Xu, Li Rao, Ying Peng, Yu-ming Li, Hong-ling Gao, and Ying-kun Guo
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
An amendment to this paper has been published and can be accessed via the original article.
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- 2020
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80. Adaptability of Turbulence Models for Pantograph Aerodynamic Noise Simulation
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Xiao-ming Tan, Peng-peng Xie, Zhi-gang Yang, and Jian-yong Gao
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Physics ,QC1-999 - Abstract
This study was targeted at CX-PG-type Faiveley pantograph of high-speed train and cylinders and analysed the fluctuating flow field around these objects by using the large eddy simulation (LES) model, the scale adaptive simulation (SAS) model, the improved delayed detached eddy simulation with shear-stress transport-kω (IDDES sst-kω) model, the delayed detached eddy simulation with shear-stress transport-kω (DDES sst-kω) model, and the delayed detached eddy simulation with realizable-kε (DDES R-kε) model. The space distributions of velocity, vorticity, and vortex structures were compared to investigate their performances on simulating fluctuating flow fields and computing aeroacoustic sources through Fourier transformation based on the surface fluctuating pressures. Furthermore, the far-field radiated noise was calculated based on the Ffowcs Williams–Hawkings equation. Based on the computation precision of the five models, a feasible turbulent model was selected for simulating aerodynamic noise. The relative errors to the results from wind-tunnel experiments of the sound pressure level (SPL) were obtained as 0.7%, 1.6%, 7.8%, 3.8%, and 12.1%, respectively, and the peak Strouhal numbers were obtained as 2.0%, 8.5%, 5.5%, 11.5%, and 51.0% for cylinder simulation. Moreover, the relative errors of SAS, IDDES sst-kω, DDES sst-kω, and DDES R-kε models to the result from LES of SPL were respectively obtained as 2.3%, 4.5%, 5.6%, and 10.8% for pantograph. Thus, it is conclusive that none of the aforementioned models are comparable with the LES model with respect to the precision in the aeroacoustic simulation. However, SAS, IDDES sst-kω, and DDES sst-kω are practically competent with the LES model considering the numerical simulations with respect to the engineering computation precision. The numerical computation model was verified using the wind-tunnel test results.
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- 2019
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81. Characteristics and Mechanism Analysis of Aerodynamic Noise Sources for High-Speed Train in Tunnel
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Xiao-Ming Tan, Hui-fang Liu, Zhi-Gang Yang, Jie Zhang, Zhong-gang Wang, and Yu-wei Wu
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Electronic computers. Computer science ,QA75.5-76.95 - Abstract
We aim to study the characteristics and mechanism of the aerodynamic noise sources for a high-speed train in a tunnel at the speeds of 50 m/s, 70 m/s, 83 m/s, and 97 m/s by means of the numerical wind tunnel model and the nonreflective boundary condition. First, the large eddy simulation model was used to simulate the fluctuating flow field around a 1/8 scale model of a high-speed train that consists of three connected vehicles with bogies in the tunnel. Next, the spectral characteristics of the aerodynamic noise source for the high-speed train were obtained by performing a Fourier transform on the fluctuating pressure. Finally, the mechanism of the aerodynamic noise was studied using the sound theory of cavity flow and the flow field structure. The results show that the spectrum pattern of the sound source energy presented broadband and multipeak characteristics for the high-speed train. The dominant distribution frequency range is from 100 Hz to 4 kHz for the high-speed train, accounting for approximately 95.1% of the total sound source energy. The peak frequencies are 400 Hz and 800 Hz. The sound source energy at 400 Hz and 800 Hz is primarily from the bogie cavities. The spectrum pattern of the sound source energy has frequency similarity for the bottom structure of the streamlined part of the head vehicle. The induced mode of the sound source energy is probably the dynamic oscillation mode of the cavity and the resonant oscillation mode of the cavity for the under-car structure at 400 Hz and 800 Hz, respectively. The numerical computation model was checked by the wind tunnel test results.
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- 2018
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82. Differentiation between tuberculosis and leukemia in abdominal and pelvic lymph nodes: evaluation with contrast-enhanced multidetector computed tomography
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Ge Zhang, Zhi-gang Yang, Jin Yao, Wen Deng, Shuai Zhang, Hua-yan Xu, and Qi-hua Long
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Tuberculosis ,Leukemia ,MDCT ,Lymph node ,Abdomen ,Pelvic cavity ,Medicine (General) ,R5-920 - Abstract
PURPOSE: To compare the characteristics of tubercular vs. leukemic involvement of abdominopelvic lymph nodes using multidetector computed tomography (CT). MATERIALS AND METHODS: We retrospectively reviewed multidetector computed tomography features including lymph node size, shape, enhancement patterns, and anatomical distribution, in 106 consecutive patients with newly diagnosed, untreated tuberculosis (55 patients; 52%) or leukemia (51 patients; 48%). In patients with leukemia, 32 (62.7%) had chronic lymphocytic leukemia, and 19 (37.3%) had acute leukemias; of these, 10 (19.6%) had acute myeloid leukemia, and 9 (17.6%) had acute lymphocytic leukemia. RESULTS: The lower para-aortic (30.9% for tuberculosis, 63.2% for acute leukemias and 87.5% for chronic lymphocytic leukemia) and inguinal (9.1% for tuberculosis, 57.9% for acute leukemias and 53.1% for chronic lymphocytic leukemia) lymph nodes were involved more frequently in the three types of leukemia than in tuberculosis (both with p
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- 2015
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83. Assessment of transposition of the great arteries associated with multiple malformations using dual-source computed tomography.
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Lin-Jun Xie, Li Jiang, Zhi-Gang Yang, Ke Shi, Hua-Yan Xu, Rui Li, Kai-Yue Diao, and Ying-Kun Guo
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Medicine ,Science - Abstract
To determine the value of dual-source computed tomography (DSCT) in depicting the morphological characteristics and diagnosing the associated malformations for patients with transposition of the great arteries (TGA) before surgery.Twenty-five patients with TGA who underwent DSCT and transthoracic echocardiography (TTE) examination were retrospectively reviewed. The morphological types of TGA, the spatial relationship between the pulmonary artery and the aorta, as well as coronary artery-associated abnormalities were assessed by DSCT. In contrast to TTE, the diagnostic accuracy of associated malformations on DSCT were analyzed and calculated with reference to surgical or digital subtraction angiography (DSA) findings. Effective doses (EDs) were also calculated.Among the 25 patients, 12 (48%) had ventricular septal defects and left ventricular outflow tract stenosis. Sixteen patients (16/25, 64%) had great arteries with an oblique spatial relationship on DSCT. In addition, we found seven patients (7/25, 28%) with coronary artery malformation, including five with an abnormal coronary origin and two with signs of a myocardial bridge. According to DSA or surgical findings, DSCT was superior to TTE in demonstrating extracardiac anomalies (sensitivity, anomalies of great vessels: 100% vs. 93.33%, other anomalies: 100% vs. 46.15%). The mean estimated ED for those aged
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- 2017
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84. Inhibitory Effects of Constituents from Euphorbia lunulata on Differentiation of 3T3-L1 Cells and Nitric Oxide Production in RAW264.7 Cells
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Susumu Kitanaka, Atsuko Ohmura, Yan Shen, Liu-Nan Jia, and Zhi-Gang Yang
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Euphorbia lunulata Bge. ,flavonol galactopyranoside gallate ,phenolic constituents ,adipocyte ,macrophage ,Organic chemistry ,QD241-441 - Abstract
A new flavonol galactopyranoside, myricetin 3-O-(2'',3''-digalloyl)-β-D-galactopyranoide (1), and 23 known constituents, including myricetin 3-O-(2''-galloyl)-β-D-galactopyranoide (2), myricitrin (3), myricetin (4), quercetin 3-O-(2'', 3''-digalloyl)-β-D-galactopyranoide (5), quercetin 3-O-(2''-galloyl)-β-D-galactopyranoide (6), hyperin (7), isoquercetrin (8), quercetin (9), kaempferol (10), apigenin (11), luteolin (12), 3-O-methylquercetin (13), 5,7,2',5'-tetrahydroxyflavone (14), 1,3,4,6-tetra-O-galloyl-β-D-glucose (15), 1,2,6-tri-O-galloyl-β-D-glucose (16), 1,3,6-tri-O-galloyl-β-D-glucose (17), gallic acid (18), protocatechuic acid (19), 3,4,5-trimethoxybenzoic acid (20), 2,6-dihydroxyacetophenone (21), 3,3'-di-O-methylellagic acid (22), ellagic acid (23) and esculetin (24) were isolated from Euphorbia lunulata Bge. Their structures were determined by spectroscopic analysis. Isolated hydrolysable tannins, flavonoids, and flavonol galactopyranoside gallates showed significant inhibition of the differentiation of 3T3-L1 preadipocytes and triglyceride accumulation in maturing adipocytes, and nitric oxide production in RAW 264.7 cells.
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- 2011
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85. Inhibitory Effects of Constituents from Morus alba var. multicaulis on Differentiation of 3T3-L1 Cells and Nitric Oxide Production in RAW264.7 Cells
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Susumu Kitanaka, Satoshi Takamatsu, Zhi-Gang Yang, and Keiichi Matsuzaki
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Morus alba var. multicaulis Perro ,arylbenzofuran ,prenyl-flavonoid ,adipocyte ,macrophage ,Organic chemistry ,QD241-441 - Abstract
A new arylbenzofuran, 3',5'-dihydroxy-6-methoxy-7-prenyl-2-arylbenzofuran (1), and 25 known compounds, including moracin R (2), moracin C (3), moracin O (4), moracin P (5), artoindonesianin O (6), moracin D (7), alabafuran A (8), mulberrofuran L (9), mulberrofuran Y (10), kuwanon A (11), kuwanon C (12), kuwanon T (13), morusin (14), kuwanon E (15), sanggenon F (16), betulinic acid (17), uvaol (18), ursolic acid (19), β-sitosterol (20), oxyresveratrol 2-O-β-D-glucopyranoside (21), mulberroside A (22), mulberroside B (23), 5,7-dihydroxycoumarin 7-O-β-D-glucopyranoside (24), 5,7-dihydroxycoumarin 7-O-β-D-apiofuranosyl-(1→6)-O-β-D-glucopyranoside (25) and adenosine (26), were isolated from Morus alba var. multicaulis Perro. (Moraceae). Their structures were determined by spectroscopic methods. The prenyl-flavonoids 11–14, 16, triterpenoids 17,18 and 20 showed significant inhibitory activity towards the differentiation of 3T3-L1 adipocytes. The arylbenzofurans 1–10 and prenyl-flavonoids 11–16 also showed significant nitric oxide (NO) production inhibitory effects in RAW264.7 cells.
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- 2011
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86. A Novel Thiophene-Fused Polycyclic Aromatic with a Tetracene Core: Synthesis, Characterization, Optical and Electrochemical Properties
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Yasushiro Nishioka, Gao-Yang Zhao, Susumu Kitanaka, Zhi-Gang Yang, Daiki Hoshino, Zong-Fan Duan, and Xian-Qiang Huang
- Subjects
polycyclic aromatics ,oxidative cyclization ,organic semiconductor materials ,Organic chemistry ,QD241-441 - Abstract
FeCl3-mediated oxidative cyclization was successfully used to construct an extended thiophene-pendant pyrene skeleton and synthesize a novel thiophene-fused polycyclic aromatic (THTP-C) with a tetracene core. The identity of the compound was confirmed by 1H-NMR, 13C-NMR, MS, and elemental analysis. Meanwhile, a single crystal of THTP-C was obtained and analyzed by X-ray single-crystal diffraction. THTP-C has a “saddle” shaped π-conjugated 1-D supramolecular structure, and favors highly ordered self-assembly by π-π interactions as evidenced by its concentration-dependent 1H-NMR spectra in solution. The optical properties of THTP-C were investigated by ultraviolet-visible (UV-Vis) and photoluminescence (PL) spectroscopy and its electrochemical properties were investigated by cyclic voltammetry (CV). The relatively large band gap (2.86 eV), low EHOMO level (−5.64 eV) and intermolecular π-π interactions imply that THTP-C has a high stability against photo-degradation and oxidation, and may be a promising candidate for stable hole-transporting materials.
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- 2011
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87. Earthquake-related pelvic crush fracture vs. non-earthquake fracture on digital radiography and MDCT: a comparative study
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Tian-wu Chen, Zhi-gang Yang, Zhi-hui Dong, Si-shi Tang, Zhi-gang Chu, and Heng Shao
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Earthquake ,Pelvis ,Fracture ,Digital radiography ,Multidetector row computed tomography ,Medicine (General) ,R5-920 - Abstract
OBJECTIVE: To determine the features of earthquake-related pelvic crush fractures versus non-earthquake fractures with digital radiography and multidetector row computed tomography. METHODS: One hundred and sixty-seven survivors with pelvic crush fractures in the 2008 Sichuan earthquake were entered in our study as the earthquake-related group (139 underwent digital radiography, 28 underwent multidetector row computed tomography); 70 victims with non-earthquake pelvic fractures were enrolled into this study as the non-earthquake group (54 underwent digital radiography, 16 underwent multidetector row computed tomography). Data were reviewed retrospectively between groups, focusing on anatomic distributions, status of pelvic bone fractures, numbers of pelvic bones involved, and classification of pelvic ring fractures according to the Tile classification system. RESULTS: Pelvic fractures occurred more frequently in the pubis in the earthquake-related group than in the non-earthquake group (135/167, 81% vs. 48/70, 69%). In addition, comminuted fractures were more common in the earthquake-related group than in the non-earthquake group (55/167, 33% vs. 10/70, 14%). Multiple fractures were less common in the earthquake-related group than in the non-earthquake group (81/167, 49% vs. 46/70, 66%). Regarding the classification of pelvic ring fractures, Type C predominantly composed of subtype C3 occurred more frequently (64/167, 38% vs. 12/70, 17%), and Type A was less common in the earthquake-related group than in the non-earthquake group (31/167, 19% vs. 23/70, 32%). All differences were statistically significant (p
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- 2011
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88. Thoracic Injuries in earthquake-related versus non-earthquake-related trauma patients: differentiation via Multi-detector Computed Tomography
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Zhi-hui Dong, Zhi-gang Yang, Tian-wu Chen, Zhi-gang Chu, Wen Deng, and Heng Shao
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Thorax ,Rib ,Injury ,Earthquake ,Tomography ,X-ray computed ,Medicine (General) ,R5-920 - Abstract
PURPOSE: Massive earthquakes are harmful to humankind. This study of a historical cohort aimed to investigate the difference between earthquake-related crush thoracic traumas and thoracic traumas unrelated to earthquakes using a multi-detector Computed Tomography (CT). METHODS: We retrospectively compared an earthquake-exposed cohort of 215 thoracic trauma crush victims of the Sichuan earthquake to a cohort of 215 non-earthquake-related thoracic trauma patients, focusing on the lesions and coexisting injuries to the thoracic cage and the pulmonary parenchyma and pleura using a multi-detector CT. RESULTS: The incidence of rib fracture was elevated in the earthquake-exposed cohort (143 vs. 66 patients in the non-earthquake-exposed cohort, Risk Ratio (RR) = 2.2; p
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- 2011
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89. Comparative study of earthquake-related and non-earthquake-related head traumas using multidetector computed tomography
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Zhi-gang Chu, Zhi-gang Yang, Zhi-hui Dong, Tian-wu Chen, Zhi-yu Zhu, and Heng Shao
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Earthquake ,Cranio-maxillofacial trauma ,Tomography ,X-ray computed ,Medicine (General) ,R5-920 - Abstract
OBJECTIVE: The features of earthquake-related head injuries may be different from those of injuries obtained in daily life because of differences in circumstances. We aim to compare the features of head traumas caused by the Sichuan earthquake with those of other common head traumas using multidetector computed tomography. METHODS: In total, 221 patients with earthquake-related head traumas (the earthquake group) and 221 patients with other common head traumas (the non-earthquake group) were enrolled in our study, and their computed tomographic findings were compared. We focused the differences between fractures and intracranial injuries and the relationships between extracranial and intracranial injuries. RESULTS: More earthquake-related cases had only extracranial soft tissue injuries (50.7% vs. 26.2%, RR=1.9), and fewer cases had intracranial injuries (17.2% vs. 50.7%, RR = 0.3) compared with the non-earthquake group. For patients with fractures and intracranial injuries, there were fewer cases with craniocerebral injuries in the earthquake group (60.6% vs. 77.9%, RR = 0.8), and the earthquake-injured patients had fewer fractures and intracranial injuries overall (1.5 + 0.9 vs. 2.5 +1.8; 1.3 + 0.5 vs. 2.1 + 1.1). Compared with the non-earthquake group, the incidences of soft tissue injuries and cranial fractures combined with intracranial injuries in the earthquake group were significantly lower (9.8% vs. 43.7%, RR = 0.2; 35.1% vs. 82.2%, RR = 0.4). CONCLUSION: As depicted with computed tomography, the severity of earthquake-related head traumas in survivors was milder, and isolated extracranial injuries were more common in earthquake-related head traumas than in non-earthquake-related injuries, which may have been the result of different injury causes, mechanisms and settings.
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- 2011
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90. Reliability analysis method for slope stability based on sample weight
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Zhi-gang Yang, Tong-chun Li, and Miao-lin Dai
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reliability analysis ,slope stability ,sample weight coefficient ,t-distribution ,Bayes formula ,River, lake, and water-supply engineering (General) ,TC401-506 - Abstract
The single safety factor criteria for slope stability evaluation, derived from the rigid limit equilibrium method or finite element method (FEM), may not include some important information, especially for steep slopes with complex geological conditions. This paper presents a new reliability method that uses sample weight analysis. Based on the distribution characteristics of random variables, the minimal sample size of every random variable is extracted according to a small sample t-distribution under a certain expected value, and the weight coefficient of each extracted sample is considered to be its contribution to the random variables. Then, the weight coefficients of the random sample combinations are determined using the Bayes formula, and different sample combinations are taken as the input for slope stability analysis. According to one-to-one mapping between the input sample combination and the output safety coefficient, the reliability index of slope stability can be obtained with the multiplication principle. Slope stability analysis of the left bank of the Baihetan Project is used as an example, and the analysis results show that the present method is reasonable and practicable for the reliability analysis of steep slopes with complex geological conditions.
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- 2009
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91. Assessment of Double Outlet Right Ventricle Associated with Multiple Malformations in Pediatric Patients Using Retrospective ECG-Gated Dual-Source Computed Tomography.
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Ke Shi, Zhi-gang Yang, Jing Chen, Ge Zhang, Hua-yan Xu, and Ying-kun Guo
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Medicine ,Science - Abstract
To evaluate the feasibility and diagnostic accuracy of retrospective electrocardiographically (ECG)-gated dual-source computed tomography (DSCT) for the assessment of double outlet right ventricle (DORV) and associated multiple malformations in pediatric patients.Forty-seven patients
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- 2015
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92. China's growing contribution to global intracranial aneurysm research (1991-2012): a bibliometric study.
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Ze-jun Jia, Bo Hong, Da-ming Chen, Qing-hai Huang, Zhi-gang Yang, Cha Yin, Xiao-qun Deng, and Jian-min Liu
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Medicine ,Science - Abstract
BACKGROUND: We sought to analyze the growing worldwide trends of intracranial aneurysm research, investigate China's recent contribution, and compare the contributions of mainland China, Taiwan, and Hong Kong. METHODS: Global and China intracranial aneurysm-related publications were retrieved from the Web of Science database from 1991 to 2012. Excel 2007, Matlab, and Thomson Data Analyzer (TDA) software were used to analyze the search results for number of publications, cited frequency, h-index, and organization contributions. RESULTS: 16468 global papers were identified that were cited 273500 times until 2013-08-15. The United States accounted for 31.497% of the articles, 58.64% of the citations, and the highest h-index (127). Japan and Germany followed in frequency. China's articles ranked eighth (third in 2012) in total number, with most of the contributions occurring since 2002 (91.33%). China was at the early stage of the logic growth curve (exponential growth), with the citation frequency and h-index per year increasing. The quality of the publications was low. The main research centers were located in Beijing, Shanghai, Taiwan, and Hong Kong. The main Asian funding body was the National Natural Science Foundation of China. The number of publications and frequency of citations of papers from mainland China was greater than that of Taiwan or Hong Kong. CONCLUSION: Global intracranial aneurysm research has been developing swiftly since 1991, with the United States making the largest contribution. Research in China started later, in 2002. Since then, China has increased its rate of publication, and became the third largest contributor by 2012.
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- 2014
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93. Assessing right ventricular function in patients with hypertrophic cardiomyopathy with cardiac MRI: correlation with the New York Heart Function Assessment (NYHA) classification.
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Shuai Zhang, Zhi-Gang Yang, Jia-Yu Sun, Ling-Yi Wen, Hua-Yan Xu, Ge Zhang, and Ying-Kun Guo
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Medicine ,Science - Abstract
PURPOSE: To determine whether 3.0-T magnetic resonance imaging (MRI) could assess right ventricular (RV) function in patients with hypertrophic cardiomyopathy (HCM), and if this assessment is correlated with the New York Heart Function Assessment (NYHA) classification. MATERIALS AND METHODS: Forty-six patients with HCM and 23 normal individuals were recruited. Left and right ventricular function parameters including end-diastolic and end-systolic volumes (EDV, ESV), stroke volume (SV) and ejection fraction (EF) and dimensions were measured and compared using 3.0-T MRI. RV function parameters between HCM patients and controls were compared using independent sample t tests. A one way ANOVA test with Bonferroni correction was used to determine significant differences among different NYHA groups. Receiver operating characteristic analyses calculated the sensitivity and specificity of RV dysfunction on MRI for the prediction of HCM severity. RESULTS: Statistical analysis revealed significant differences of left ventricular (LV) and RV volumetric values and masses between the HCM patients and controls (all p0.05). However, significant differences between the Class IV and I-III groups (all P
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- 2014
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94. Coherence and reduced order analyses of flow field and aerodynamic noise for full-scale high-speed trains pantograph
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Qi-liang, Li, Zhuo-ming, Li, Meng-han, Ouyang, and Zhi-gang, Yang
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- 2022
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95. Flow structure and far-field noise of high-speed train under ballast track
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Zhuo-ming, Li, Qi-liang, Li, and Zhi-gang, Yang
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- 2022
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96. miR–483-5p promotes prostate cancer cell proliferation and invasion by targeting RBM5
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Zhi-Gang Yang, Xu-Dong Ma, Zhao-Hui He, and Ying-xin Guo
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MIRN483 microRNA, human [Supplementary Concept] ,RBM5 protein, human [Supplementary Concept] ,Prostatic Neoplasms ,Growth ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
ABSTRACT Objective: miR-483-5p has been identified as a miRNA oncogene in certain cancers. However, its role in prostate cancer has not been sufficiently investigated. In this study, we investigated the role of miR-483-5p in prostate cancer and examined RBM5 regulation by miR-483-5p. Material and methods: Expression levels of miR-483-5p were determined by quantitative real-time PCR. The effect of miR-483-5p on proliferation was evaluated by MTT assay, cell invasion was evaluated by trans-well invasion assays, and target protein expression was determined by western blotting in LNCaP, DU-145, and PC-3 cells. Luciferase reporter plasmids were constructed to confirm the action of miR-483-5p on downstream target gene RBM5 in HEK-293T cells. Results: we observed that miR-483-5p was upregulated in prostate cancer cell lines and tissues. A miR-483-5p inhibitor inhibited prostate cancer cell growth and invasion in DU-145 and PC-3 cells. miR-483-5p directly bound to the 3' untranslated region (3'UTR) of RBM5 in HEK-293T cells. RBM5 overexpression inhibited prostate cancer cell growth and invasion in LNCaP cells. Enforced RBM5 expression alleviated miR-483-5p promotion of prostate cancer cell growth and invasion in LNCaP cells. Conclusion: The present study describes a potential mechanism underlying a miR-483-5p/RBM5 link that contributes to prostate cancer development.
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97. Vortex structures and aeroacoustic performance of the flow field of the pantograph
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Xiao-Ming, Tan, Zhi-Gang, Yang, Xi-ming, Tan, Xiao-long, Wu, and Jie, Zhang
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- 2018
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98. Anti‐phytopathogenic activity and the mechanisms of phthalides from Angelica sinensis (Oliv.) Diels
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Yan‐Yan Ding, Yu Sun, Xiong‐Fei Luo, Shao‐Yong Zhang, Rui Wang, Zhi‐Gang Yang, Jing‐Ru Wang, Bao‐Qi Zhang, Zhi‐Jun Zhang, Yue Ma, Jun‐Xia An, Han Zhou, and Ying‐Qian Liu
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Insect Science ,General Medicine ,Agronomy and Crop Science - Published
- 2023
99. Impact of Metabolic Syndrome on Left Ventricular Deformation and Myocardial Energetic Efficiency Compared Between Women and Men: An <scp>MRI</scp> Study
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Shan Huang, Yuan Li, Ke Shi, Jin Wang, Li Jiang, Yue Gao, Wei‐Feng Yan, and Zhi‐Gang Yang
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Radiology, Nuclear Medicine and imaging - Abstract
Metabolic and hemodynamic alterations in metabolic syndrome (MetS) can cause a reduced myocardial energetic efficiency (MEE). Indexed MEE (MEEi), as a simple estimate of MEE, is emerging as a novel and useful imaging parameter.To investigate the impact of MetS on MEE and systolic myocardial strain and to assess any sex difference.Retrospective.A total of 161 patients with MetS (female: n = 82, 52.2 ± 11.7 years; male: n = 79, 51.8 ± 10.6 years) and 77 healthy subjects (female: n = 46, 52.7 ± 8.2 years; male: n = 31, 54.1 ± 11.2 years). Patients with left ventricular (LV) ejection fraction50% were excluded.A 3.0 T; balanced steady-state free precession sequence.LV volumes and mass (LVM) and global longitudinal strain (GLS) were obtained by MRI. Stroke volume (SV) divided by HR was used as a surrogate measure of MEE and normalized to LVM (MEEi).Student's t-test or Mann-Whitney U-test; Multivariable linear regression (coefficient of determination, RFor both males and females, MEEi and GLS were lower in MetS patients than in the normal controls. Among MetS patients, men had significantly higher LVM (59.7 ± 13.4 g/mMEEi was significantly impaired in MetS without overt systolic dysfunction. There was a sex difference regarding the cardiac alterations in MetS, with men having significantly lower MEEi and GLS and significantly higher LVM than women. Further, MEEi was independently associated with GLS.3 TECHNICAL EFFICACY: Stage 3.
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- 2022
100. Prognostic Value of Left Atrial Reservoir Strain in Left Ventricular Myocardial Noncompaction: A 3.0 T Cardiac Magnetic Resonance Feature Tracking Study
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Pei‐Lun Han, Meng‐Ting Shen, Yu Jiang, Ze‐Kun Jiang, Kang Li, and Zhi‐Gang Yang
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Radiology, Nuclear Medicine and imaging - Abstract
The relationship of left atrial (LA) strain to high-risk heart failure (HF) events in patients with left ventricular myocardial noncompaction (LVNC) remains to be thoroughly investigated.To evaluate the LA performance in patients with LVNC, and to investigate the prognostic value of LA phasic strain on high-risk HF events, and its influencing factors.Retrospective.A total of 95 LVNC patients (74 with LA enlargement [LAE] and 21 without LAE) and 50 healthy controls.A 3.0 T, balanced steady-state free-precession cine imaging.LA longitudinal strains were measured by cardiac MRI feature tracking technique. LA volume index (LAVI) and LA ejection fraction (LAEF) were calculated. Their intraobserver and interobserver reproducibility were evaluated. The primary outcome was high-risk HF events, a composite of first HF hospitalization, hospitalization for worsening HF and death from HF.Student's t/Mann-Whitney U, one-way analysis of variance/Kruskal-Wallis, Chi-squared, receiver operating characteristic, Kaplan-Meier, log-rank, Cox regression, Pearson and Spearman correlation and linear regression analyses were performed. The significance threshold was set at P 0 .05.LAEF and LA longitudinal strains decreased in LVNC patients irrespective of the presence of LAE. During a median follow-up of 32.17 months, high-risk HF occurred in 13 (13.68%) patients. Patients with increased LAVI, decreased LAEF and decreased LA longitudinal strain had significantly higher risks of high-risk HF events. In patients with LVNC, LA reservoir strain (εs) was independently associated with high-risk HF (hazard ratio = 23.208 [95% CI: 2.993-179.967]). LV global longitudinal strain (LV GLS) (β = -1.783 [95% CI: -2.493 to -1.073]) was significantly and independently associated with εs. Intraobserver and interobserver reproducibility was excellent for LAVI, LAEF, and LA strain.In patients with LVNC, εs was an independent predictor for high-risk HF events. LV GLS was an independent determinant of εs in LVNC.4 TECHNICAL EFFICACY: Stage 4.
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- 2022
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