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1.
Insect Mol Biol ; 33(1): 41-54, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37740676

ABSTRACT

Caddisworms (Trichoptera) spin adhesive silks to construct a variety of underwater composite structures. Many studies have focused on the fibroin heavy chain of caddisworm silk and found that it contains heavy phosphorylation to maintain a stable secondary structure. Besides fibroins, recent studies have also identified some new silk proteins within caddisworm silk. To better understand the silk composition and its secretion process, this study reports the silk gland proteome of a retreat-building caddisworm, Stenopsyche angustata Martynov (Trichoptera, Stenopsychidae). Using liquid chromatography tandem mass spectrometry (LC-MS/MS), 2389 proteins were identified in the silk gland of S. angustata, among which 192 were predicted as secreted silk proteins. Twenty-nine proteins were found to be enriched in the front silk gland, whereas 109 proteins were enriched in the caudal silk gland. The fibroin heavy chain and nine uncharacterized silk proteins were identified as phosphorylated proteins. By analysing the sequence of the fibroin heavy chain, we found that it contains 13 Gly/Thr/Pro-rich regions, 12 Val/Ser/Arg-rich regions and a Gly/Arg/Thr-rich region. Three uncharacterized proteins were identified as sericin-like proteins due to their larger molecular weights, signal peptides and repetitive motifs rich in serine. This study provides valuable information for further clarifying the secretion and adhesion of underwater caddisworm silk.


Subject(s)
Bombyx , Fibroins , Animals , Silk/chemistry , Fibroins/genetics , Fibroins/chemistry , Insecta/metabolism , Larva/metabolism , Proteome/metabolism , Chromatography, Liquid , Tandem Mass Spectrometry , Bombyx/metabolism , Insect Proteins/metabolism
2.
Langmuir ; 40(9): 4709-4718, 2024 03 05.
Article in English | MEDLINE | ID: mdl-38388349

ABSTRACT

Constructing three-dimensional (3D) aligned nanofiber scaffolds is significant for the development of cardiac tissue engineering, which is promising in the field of drug discovery and disease mechanism study. However, the current nanofiber scaffold preparation strategy, which mainly includes manual assembly and hybrid 3D printing, faces the challenge of integrated fabrication of morphology-controllable nanofibers due to its cross-scale structural feature. In this research, a trench-guided electrospinning (ES) strategy was proposed to directly fabricate 3D aligned nanofiber scaffolds with alternative ES and a direct ink writing (DIW) process. The electric field effect of DIW poly(dimethylsiloxane) (PDMS) side walls on guiding whipping ES nanofibers was investigated to construct trench design rules. It was found that the width/height ratio of trenches greatly affected the nanofiber alignment, and the trench width/height ratio of 1.5 provided the nanofiber alignment degree over 60%. As a proof of principle, 3D nanofiber scaffolds with controllable porosity (60-80%) and alignment (30-60%) were fabricated. The effect of the scaffolds was verified by culturing human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), which resulted in the uniform 3D distribution of aligned hiPSC-CMs with ∼1000 µm thickness. Therefore, this printing strategy shows great potential for the efficient engineered tissue construction.


Subject(s)
Nanofibers , Tissue Engineering , Humans , Nanofibers/chemistry , Tissue Scaffolds/chemistry , Myocytes, Cardiac
3.
Eur Radiol ; 2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38409549

ABSTRACT

OBJECTIVES: To compare the diagnostic performance of machine learning (ML)-based computed tomography-derived fractional flow reserve (CT-FFR) and cardiac magnetic resonance (MR) perfusion mapping for functional assessment of coronary stenosis. METHODS: Between October 2020 and March 2022, consecutive participants with stable coronary artery disease (CAD) were prospectively enrolled and underwent coronary CTA, cardiac MR, and invasive fractional flow reserve (FFR) within 2 weeks. Cardiac MR perfusion analysis was quantified by stress myocardial blood flow (MBF) and myocardial perfusion reserve (MPR). Hemodynamically significant stenosis was defined as FFR ≤ 0.8 or > 90% stenosis on invasive coronary angiography (ICA). The diagnostic performance of CT-FFR, MBF, and MPR was compared, using invasive FFR as a reference. RESULTS: The study protocol was completed in 110 participants (mean age, 62 years ± 8; 73 men), and hemodynamically significant stenosis was detected in 36 (33%). Among the quantitative perfusion indices, MPR had the largest area under receiver operating characteristic curve (AUC) (0.90) for identifying hemodynamically significant stenosis, which is in comparison with ML-based CT-FFR on the vessel level (AUC 0.89, p = 0.71), with comparable sensitivity (89% vs 79%, p = 0.20), specificity (87% vs 84%, p = 0.48), and accuracy (88% vs 83%, p = 0.24). However, MPR outperformed ML-based CT-FFR on the patient level (AUC 0.96 vs 0.86, p = 0.03), with improved specificity (95% vs 82%, p = 0.01) and accuracy (95% vs 81%, p < 0.01). CONCLUSION: ML-based CT-FFR and quantitative cardiac MR showed comparable diagnostic performance in detecting vessel-specific hemodynamically significant stenosis, whereas quantitative perfusion mapping had a favorable performance in per-patient analysis. CLINICAL RELEVANCE STATEMENT: ML-based CT-FFR and MPR derived from cardiac MR performed well in diagnosing vessel-specific hemodynamically significant stenosis, both of which showed no statistical discrepancy with each other. KEY POINTS: • Both machine learning (ML)-based computed tomography-derived fractional flow reserve (CT-FFR) and quantitative perfusion cardiac MR performed well in the detection of hemodynamically significant stenosis. • Compared with stress myocardial blood flow (MBF) from quantitative perfusion cardiac MR, myocardial perfusion reserve (MPR) provided higher diagnostic performance for detecting hemodynamically significant coronary artery stenosis. • ML-based CT-FFR and MPR from quantitative cardiac MR perfusion yielded similar diagnostic performance in assessing vessel-specific hemodynamically significant stenosis, whereas MPR had a favorable performance in per-patient analysis.

4.
Prev Med ; 180: 107869, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38266581

ABSTRACT

OBJECTIVES: We aimed to seek accurate assessments of the glomerular filtration rate (GFR) in a Chinese hypertensive population to identify individuals at high risk for chronic kidney disease (CKD) progression. Then, the risk of cardiovascular disease (CVD) and all-cause death due to kidney injury were further investigated under appropriate GFR-estimation equations. METHODS: In this prospective follow-up cohort study of 10,171 hypertensive patients, we compared the discrimination power of a trio of GFR-estimation equations using Harrell's C-index, measuring the model fit by calculating the Akaike information criterion. Univariate and multivariable logistic regression analyses were respectively used to calculate the hazard ratio (HR) and 95% confidence interval [CI] values for CKD progression. In addition, we also assessed the risk of CVD and all-cause death with impaired renal function using multivariable-adjusted Cox regression models. RESULTS: The Modification of Diet in Renal Disease (MDRD) equation showed the highest C-index range for the predicted probability of CKD progression in the fully adjusted model. During MDRD analysis, a low eGFR (60-89 mL/min/1.73m2 or < 60 mL/min/1.73m2) was an independent risk factor for CVD, especially stroke (1.28 [95% CI, 1.05-1.55] and 1.89 [95% CI, 1.08-3.31]), as well as all-cause mortality (1.28 [95% CI, 1.09-1.50] and 1.68 [95% CI, 1.01-2.78]). CONCLUSIONS: The MDRD equation seems to be more suitable for screening CKD progression in Chinese hypertensive populations, targeting potential risk factors for effective prevention to reduce renal impairment so as to further limit CVD morbidity and mortality.


Subject(s)
Cardiovascular Diseases , Hypertension , Renal Insufficiency, Chronic , Adult , Humans , Prospective Studies , Follow-Up Studies , Glomerular Filtration Rate , Kidney , China/epidemiology , Creatinine
5.
Sensors (Basel) ; 24(5)2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38474909

ABSTRACT

Simultaneous Localization and Mapping (SLAM), as one of the core technologies in intelligent robotics, has gained substantial attention in recent years. Addressing the limitations of SLAM systems in dynamic environments, this research proposes a system specifically designed for plant factory transportation environments, named GY-SLAM. GY-SLAM incorporates a lightweight target detection network, GY, based on YOLOv5, which utilizes GhostNet as the backbone network. This integration is further enhanced with CoordConv coordinate convolution, CARAFE up-sampling operators, and the SE attention mechanism, leading to simultaneous improvements in detection accuracy and model complexity reduction. While mAP@0.5 increased by 0.514% to 95.364, the model simultaneously reduced the number of parameters by 43.976%, computational cost by 46.488%, and model size by 41.752%. Additionally, the system constructs pure static octree maps and grid maps. Tests conducted on the TUM dataset and a proprietary dataset demonstrate that GY-SLAM significantly outperforms ORB-SLAM3 in dynamic scenarios in terms of system localization accuracy and robustness. It shows a remarkable 92.59% improvement in RMSE for Absolute Trajectory Error (ATE), along with a 93.11% improvement in RMSE for the translational drift of Relative Pose Error (RPE) and a 92.89% improvement in RMSE for the rotational drift of RPE. Compared to YOLOv5s, the GY model brings a 41.5944% improvement in detection speed and a 17.7975% increase in SLAM operation speed to the system, indicating strong competitiveness and real-time capabilities. These results validate the effectiveness of GY-SLAM in dynamic environments and provide substantial support for the automation of logistics tasks by robots in specific contexts.

6.
Cardiovasc Diabetol ; 22(1): 121, 2023 05 22.
Article in English | MEDLINE | ID: mdl-37217967

ABSTRACT

BACKGROUND: Pericoronary adipose tissue (PCAT) density is a biomarker of vessel inflammation, which is supposed to be increased in patients with type 2 diabetes mellitus (T2DM). However, whether the coronary inflammation revealed by this novel index could be alleviated after evolocumab treatment in T2DM remains unknown. METHODS: From January 2020 to December 2022, consecutive T2DM patients with low-density lipoprotein cholesterol ≥ 70 mg/dL on maximally tolerated statin and taking evolocumab were prospectively included. In addition, patients with T2DM who were taking statin alone were recruited as control group. The eligible patients underwent baseline and follow-up coronary CT angiography with an interval of 48-week. To render patients with evolocumab as comparable to those controls, a propensity-score matching design was used to select the matched pairs with a 1:1 ratio. Obstructive lesion was defined as the extent of coronary artery stenosis ≥ 50%; the numbers inside the brackets were interquartile ranges. RESULTS: A total of 170 T2DM patients with stable chest pain were included [(mean age 64 ± 10.6 [range 40-85] years; 131 men). Among those patients, 85 were in evolocumab group and 85 were in control group. During follow-up, low-density lipoprotein cholesterol (LDL-C) level (2.02 [1.26, 2.78] vs. 3.34 [2.53, 4.14], p < 0.001), and lipoprotein(a) (12.1 [5.6, 21.8] vs. 18.9 [13.2, 27.2], p = 0.002) were reduced after evolocumab treatment. The prevalence of obstructive lesions and high-risk plaque features were significantly decreased (p < 0.05 for all). Furthermore, the calcified plaque volume were significantly increased (188.3 [115.7, 361.0] vs. 129.3 [59.5, 238.3], p = 0.015), while the noncalcified plaque volume and necrotic volume were diminished (107.5 [40.6, 180.6] vs. 125.0 [65.3, 269.7], p = 0.038; 0 [0, 4.7] vs. 0 [0, 13.4], p < 0.001, respectively). In addition, PCAT density of right coronary artery was significantly attenuated in evolocumab group (- 85.0 [- 89.0, - 82.0] vs. - 79.0 [- 83.5, - 74.0], p < 0.001). The change in the calcified plaque volume inversely correlated with achieved LDL-C level (r = - 0.31, p < 0.001) and lipoprotein(a) level (r = - 0.33, p < 0.001). Both the changes of noncalcified plaque volume and necrotic volume were positively correlated with achieved LDL-C level and Lp(a) (p < 0.001 for all). However, the change of PCATRCA density only positively correlated with achieved lipoprotein(a) level (r = 0.51, p < 0.001). Causal mediation analysis revealed Lp(a) level mediated 69.8% (p < 0.001) for the relationship between evolocumab and changes of PCATRCA. CONCLUSIONS: In patients with T2DM, evolocumab is an effective therapy to decrease noncalcified plaque volume necrotic volume, and increase calcified plaque volume. Furthermore, evolocumab could attenuate PCAT density, at least in part, via the reduction of lipoprotein(a).


Subject(s)
Coronary Artery Disease , Diabetes Mellitus, Type 2 , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Plaque, Atherosclerotic , Adult , Aged , Aged, 80 and over , Humans , Male , Middle Aged , Adipose Tissue , Cholesterol, LDL , Computed Tomography Angiography , Coronary Angiography , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/pathology , Follow-Up Studies , Hydroxymethylglutaryl-CoA Reductase Inhibitors/adverse effects , Inflammation , Lipoprotein(a) , Plaque, Atherosclerotic/pathology , Female
7.
Langmuir ; 39(1): 411-422, 2023 Jan 10.
Article in English | MEDLINE | ID: mdl-36534012

ABSTRACT

Crude oil adhesion issues are widespread in the petroleum industry, leading to inefficient production and high maintenance costs. Developing efficient antifouling materials and investigating the microscopic adhesion mechanism are of substantial significance. In the present work, a superhydrophilic/underwater superoleophobic PAFC coating with excellent antifouling properties was constructed by the coordination-driven self-assembly of phytic acid (PA) and FeCl3 (FC). The atomic force microscope (AFM) droplet probe technique was employed to elucidate the underlying mechanism of the anti-oil-adhesion property of the PAFC coating. Results showed that the PAFC modification achieved the optimum effect at a molar ratio of 1:3 between PA and FeIII. Applying a (3-aminopropyl)triethoxysilane (APTES) interlayer can effectively improve the performance of the PAFC coating on silica substrates. AFM droplet probe experiments indicated that the adhesion force between submerged micrometer-sized oil droplets and PAFC-modified substrates was significantly weaker than that with the untreated substrate. Meanwhile, the adhesion forces between oil droplets and surfaces were inversely proportional to the contact angle of the oil in water and were enhanced by higher salinity, lower collision velocity, and stronger loading force. The oil injection and wall sticking tests also confirmed the effectiveness of the PAFC modification in resisting the adhesion of crude oil.

8.
Eur Radiol ; 33(5): 3052-3063, 2023 May.
Article in English | MEDLINE | ID: mdl-36629927

ABSTRACT

OBJECTIVES: To investigate the prognostic value of coronary CT angiography (CCTA) in heart failure patients with preserved ejection fraction (HFpEF). METHODS: Between January 2009 and December 2013, 6497 participants (mean age 63 ± 9.4 [range 32-86] years; 4111 men) who underwent CCTA and echocardiography were prospectively included. Participants were divided into HFpEF group and without HFpEF group. The primary endpoint was major adverse cardiovascular events (MACEs), including cardiovascular mortality, nonfatal myocardial infarction (MI), or hospitalization for heart failure (HF). RESULTS: Among those participants, 3096 were identified with HFpEF and 3401 were without HFpEF. Higher prevalence of coronary atherosclerosis was observed in HFpEF group than those without (78.3% vs. 64.9%, p < 0.001). During a median of 11.0 [IQR: 9.0-12.0] years follow-up, participants with HFpEF exhibit a heightened risk of MACEs in CAD-RADS = 0, 1-2, and ≥ 3 respectively (p < 0.001 for all). In the risk-adjusted hazard analysis among participants with HFpEF, CAD-RADS = 1-2 increased a 2.5-time risk for non-fatal MI (adjusted HR: 2.5, 95% CI: 1.5 to 4.3, p < 0.001), while CAD-RADS ≥ 3 conferred 3.9-fold and 3.1-fold higher risk for cardiovascular mortality (adjusted HR: 3.9, 95% CI: 2.2 to 7.1, p < 0.001) and hospitalization due to HF (adjusted HR: 3.1, 95% CI: 1.9 to 5.3, p < 0.001) with reference to CAD-RADS = 0 respectively. CONCLUSIONS: Coronary artery disease is common in participants with HFpEF and associated with MACEs. Among those participants, the presence of CAD-RADS = 1-2 increased the risk of nonfatal MI, while CAD-RADS ≥ 3 were correlated with cardiovascular mortality and hospitalization due to HF. KEY POINTS: • Higher median of CACS and higher CAD-RADS categories were observed in the HFpEF group than those without (p < 0.001 for both). • Participants with HFpEF exhibit a heightened risk of MACEs in CAD-RADS = 0, 1-2, and ≥ 3 respectively (p < 0.001 for all). • In the risk-adjusted hazard analysis among participants with HFpEF, CAD-RADS =1-2 increased a 2.5-time risk for non-fatal MI (adjusted HR: 2.5, 95% CI: 1.5 to 4.3, p < 0.001) with reference to CAD-RADS = 0 respectively.


Subject(s)
Coronary Artery Disease , Heart Failure , Myocardial Infarction , Male , Humans , Adult , Middle Aged , Aged , Aged, 80 and over , Prognosis , Heart Failure/complications , Computed Tomography Angiography , Stroke Volume , Coronary Angiography , Coronary Artery Disease/complications , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/epidemiology , Risk Factors
9.
Eur Radiol ; 33(10): 7238-7249, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37145148

ABSTRACT

OBJECTIVES: We applied a fully automated pixel-wise post-processing framework to evaluate fully quantitative cardiovascular magnetic resonance myocardial perfusion imaging (CMR-MPI). In addition, we aimed to evaluate the additive value of coronary magnetic resonance angiography (CMRA) to the diagnostic performance of fully automated pixel-wise quantitative CMR-MPI for detecting hemodynamically significant coronary artery disease (CAD). METHODS: A total of 109 patients with suspected CAD were prospectively enrolled and underwent stress and rest CMR-MPI, CMRA, invasive coronary angiography (ICA), and fractional flow reserve (FFR). CMRA was acquired between stress and rest CMR-MPI acquisition, without any additional contrast agent. Finally, CMR-MPI quantification was analyzed by a fully automated pixel-wise post-processing framework. RESULTS: Of the 109 patients, 42 patients had hemodynamically significant CAD (FFR ≤ 0.80 or luminal stenosis ≥ 90% on ICA) and 67 patients had hemodynamically non-significant CAD (FFR ˃ 0.80 or luminal stenosis < 30% on ICA) were enrolled. On the per-territory analysis, patients with hemodynamically significant CAD had higher myocardial blood flow (MBF) at rest, lower MBF under stress, and lower myocardial perfusion reserve (MPR) than patients with hemodynamically non-significant CAD (p < 0.001). The area under the receiver operating characteristic curve of MPR (0.93) was significantly larger than those of stress and rest MBF, visual assessment of CMR-MPI, and CMRA (p < 0.05), but similar to that of the integration of CMR-MPI with CMRA (0.90). CONCLUSIONS: Fully automated pixel-wise quantitative CMR-MPI can accurately detect hemodynamically significant CAD, but the integration of CMRA obtained between stress and rest CMR-MPI acquisition did not provide significantly additive value. KEY POINTS: • Full quantification of stress and rest cardiovascular magnetic resonance myocardial perfusion imaging can be postprocessed fully automatically, generating pixel-wise myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) maps. • Fully quantitative MPR provided higher diagnostic performance for detecting hemodynamically significant coronary artery disease, compared with stress and rest MBF, qualitative assessment, and coronary magnetic resonance angiography (CMRA). • The integration of CMRA and MPR did not significantly improve the diagnostic performance of MPR alone.


Subject(s)
Coronary Artery Disease , Coronary Stenosis , Fractional Flow Reserve, Myocardial , Myocardial Perfusion Imaging , Humans , Coronary Artery Disease/diagnosis , Coronary Angiography/methods , Fractional Flow Reserve, Myocardial/physiology , Constriction, Pathologic , Predictive Value of Tests , Perfusion , Myocardial Perfusion Imaging/methods
10.
J Cardiovasc Magn Reson ; 25(1): 67, 2023 Nov 23.
Article in English | MEDLINE | ID: mdl-37993897

ABSTRACT

BACKGROUND: The clinical application of coronary MR angiography (MRA) combining diastole and systole imaging has never been described comprehensively in coronary artery disease (CAD) patients. We aimed to design an optimal non-contrast coronary MRA scan protocol combining diastolic and systolic imaging and to (1) evaluate its diagnostic performance for detecting significant coronary stenosis; (2) evaluate the feasibility of this protocol to noninvasively measure the coronary distensibility index (CDI). METHODS: From June 2021 to May 2022, 33 healthy volunteers and 91 suspected CAD patients scheduled for X-ray coronary angiography (CAG) were prospectively enrolled. 3T non-contrast water-fat coronary MRA was carried out twice at diastole and systole. Significant coronary stenosis was defined as a luminal diameter reduction of ≥ 50% using CAG as the reference and was evaluated as follows: (1) by coronary MRA in diastole alone; (2) by coronary MRA in systole alone; (3) by combined coronary MRA in diastole and systole. According to CAG, the patients were divided into significant CAD patients and non-significant CAD patients. The difference in CDI among participants was evaluated. RESULTS: Combined coronary MRA was completed in 31 volunteers and 76 patients. The per-patient sensitivity, specificity, and accuracy of combined coronary MRA were 97.5%, 83.3%, and 90.8%, respectively. Compared with single diastolic mode, combined coronary MRA showed equally high sensitivity but improved specificity on a per-patient basis (83.3% vs. 63.9%, adjusted P = 0.013). The CDI tested by coronary MRA decreased incrementally from healthy volunteers to non-significant and significant CAD patients. CONCLUSION: Compared with single-phase mode, 3 T non-contrast combined coronary MRA significantly improved specificity and may have potential to be a simple noninvasive method to measure CDI.


Subject(s)
Coronary Artery Disease , Coronary Stenosis , Humans , Coronary Angiography/methods , Diastole , Systole , Predictive Value of Tests , Coronary Artery Disease/diagnostic imaging , Coronary Stenosis/diagnostic imaging , Sensitivity and Specificity , Magnetic Resonance Angiography/methods
11.
BMC Med Educ ; 23(1): 357, 2023 May 22.
Article in English | MEDLINE | ID: mdl-37217963

ABSTRACT

BACKGROUND: To evaluate physicians' perceptions, experiences and expectations of clinical pharmacists in China from the perspective of physicians' demands, to improve the training of pharmacists. METHODS: A cross-sectional survey involving physicians (except for primary physicians) was conducted from July to August 2019 in China. Using a field questionnaire, this study gathered data on descriptive information about the respondents and their perceptions, experiences and expectations of clinical pharmacists. Data were analysed descriptively using frequencies, percentages and mean. Several subgroup analyses using Chi-square tests were conducted to identify physicians' demands for clinical pharmacists in China. RESULTS: A total of 1376 physicians from secondary and tertiary hospitals in China (response rate = 92%) participated. The majority of the respondents were comfortable with clinical pharmacists providing education to patients (59.09%) and detecting and preventing prescription errors (60.17%), but they appeared uncomfortable when asked about clinical pharmacists suggesting the use of prescription medications to patients (15.71%). Most respondents agreed that clinical pharmacists are a reliable source of general drug information (81.84%) instead of clinical drug information (79.58%). The majority of the respondents expected clinical pharmacists to be knowledgeable drug therapy experts (95.56%) and to educate their patients about the safe and appropriate use of medications (95.56%). CONCLUSION: Physicians' perceptions and experiences were positively associated with the frequency of their interaction with clinical pharmacists. They had high expectations of clinical pharmacists as knowledgeable drug therapy experts. Corresponding policies and measures are needed to improve the education and training system of clinical pharmacists in China.


Subject(s)
Pharmacy Service, Hospital , Physicians , Humans , Pharmacists , Cross-Sectional Studies , Attitude of Health Personnel , Professional Role , Surveys and Questionnaires
12.
Molecules ; 28(21)2023 Oct 25.
Article in English | MEDLINE | ID: mdl-37959686

ABSTRACT

Replacing expensive platinum oxygen reduction reaction (ORR) catalysts with atomically dispersed single-atom catalysts is an effective way to improve the energy conversion efficiency of fuel cells. Herein, a series of single-atom catalysts, TM-N2O2Cx (TM=Sc-Zn) with TM-N2O2 active units, were designed, and their catalytic performance for electrocatalytic O2 reduction was investigated based on density functional theory. The results show that TM-N2O2Cx exhibits excellent catalytic activity and stability in acidic media. The eight catalysts (TM=Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) are all 4e- reaction paths, among which Sc-N2O2Cx, Ti-N2O2Cx, and V-N2O2Cx follow dissociative mechanisms and the rest are consistent with associative mechanisms. In particular, Co-N2O2Cx and Ni-N2O2Cx enable a smooth reduction in O2 at small overpotentials (0.44 V and 0.49 V, respectively). Furthermore, a linear relationship between the adsorption free energies of the ORR oxygen-containing intermediates was evident, leading to the development of a volcano plot for the purpose of screening exceptional catalysts for ORR. This research will offer a novel strategy for the design and fabrication of exceptionally efficient non-precious metal catalysts on an atomic scale.

13.
J Magn Reson Imaging ; 55(2): 579-591, 2022 02.
Article in English | MEDLINE | ID: mdl-34254384

ABSTRACT

BACKGROUND: 3.0 T non-contrast-enhanced nitroglycerin (NTG)-assisted whole-heart coronary magnetic resonance angiography (MRA) employing Dixon water-fat separation and compressed SENSE (CS-SENSE) acceleration is a promising method for diagnosing coronary artery disease (CAD). PURPOSE: To evaluate the diagnostic performance of this technique for detecting clinically-relevant (≥50% diameter reducing) CAD and to evaluate the difference in NTG-induced coronary vasodilation between patients with and without clinically-relevant CAD. STUDY TYPE: Prospective. POPULATION: Sixty-six patients with suspected CAD. FIELD STRENGTH/SEQUENCE: 3.0 T; CSSENSE, Dixon water-fat separation, three-dimensional segmented turbo field gradient-echo sequence for whole-heart coronary MRA. ASSESSMENT: Overall image quality of coronary MRA was calculated on the basis of all visible coronary segments. The diagnostic performance of coronary MRA for detecting a ≥50% reduction in coronary artery diameter with and without NTG was compared using X-ray coronary angiography (CAG) as the reference. According to CAG, patients were divided into a non-clinically-relevant CAD group and clinically-relevant CAD group, and the difference in NTG-induced vasodilation between the groups was evaluated. STATISTICAL TESTS: Unpaired/paired Student's t-test, Mann-Whitney U test, paired Wilcoxon signed-rank test, χ2 test, McNemar test. A two-tailed P value <0.05 was considered significant. RESULTS: Overall image quality was increased significantly in the coronary MRA images after NTG. The diagnostic performance of the non-NTG vs. NTG-assisted coronary MRA was as follows on a per-patient basis: sensitivity 94.3% vs. 94.3%, specificity 64.5% vs. 83.9%, positive predictive value 75.0% vs. 86.8%, negative predictive value 90.9% vs. 92.9%, and accuracy 80.3% vs. 89.4%, respectively. NTG-induced vasodilation was significantly lower in the clinically-relevant CAD group than in the non-clinically-relevant CAD group (13.7 ± 8.1% vs. 24.1 ± 16.3%). DATA CONCLUSION: Non-contrast Dixon water-fat separation CS-SENSE coronary MRA at 3.0 T can noninvasively detect clinically-relevant CAD and sublingual NTG improved performance. Combining pre- and post-NTG coronary MRA may provide a simple noninvasive and nonionizing test to evaluate coronary vasodilation function. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 2.


Subject(s)
Nitroglycerin , Water , Coronary Angiography , Coronary Vessels/diagnostic imaging , Humans , Magnetic Resonance Angiography , Prospective Studies , Sensitivity and Specificity , Vasodilator Agents
14.
Eur Radiol ; 32(11): 7657-7667, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35567603

ABSTRACT

OBJECTIVES: Immune checkpoint inhibitor (ICI)-associated myocarditis is a potentially fatal complication. Sparse published researches evaluated the prognostic value of cardiovascular magnetic resonance feature tracking (CMR-FT) for ICI-associated myocarditis. METHODS: In the single-center retrospective study, 52 patients with ICI-associated myocarditis and CMR were included from August 2018 to July 2021. The ICI-associated myocarditis was diagnosed by using the clinical criteria of the European Society of Cardiology guidelines. Major adverse cardiovascular events (MACE) were comprised of cardiovascular death, cardiogenic shock, cardiac arrest, and complete heart block. RESULTS: During a median follow-up of 171 days, 14 (27%) patients developed MACE. For patients with MACE, the global circumferential strain (GCS), global radial strain (GRS), global longitudinal strain (GLS), and left ventricular ejection fraction (LVEF) were significantly worse and native T1 values and late gadolinium enhancement (LGE) extent were significantly increased, compared with patients without MACE (p < 0.05). The GLS remained the independent factor associated with a higher risk of MACE (hazard ratio (HR): 2.115; 95% confidence interval (CI): 1.379-3.246; p = 0.001) when adjusting for LVEF, LGE extent, age, sex, body mass index, steroid treatment, and prior cardiotoxic chemotherapy or radiation. After adjustment for LVEF, the GLS remained the independent risk factor associated with a higher rate of MACE among patients with a preserved LVEF (HR: 1.358; 95% CI: 1.007-1.830; p = 0.045). CONCLUSIONS: GLS could provide independent prognostic value over GCS, GRS, traditional CMR features, and clinical features in patients with ICI-associated myocarditis. KEY POINTS: • The global circumferential strain (GCS), global radial strain (GRS), and global longitudinal strain (GLS) by cardiovascular magnetic resonance feature tracking were significantly impaired in patients with an immune checkpoint inhibitor (ICI)-associated myocarditis. • GLS was still significantly impaired in patients with preserved left ventricular ejection fraction. • The worse GLS was an independent risk factor over GCS, GRS, traditional CMR features, and clinical features for predicting major adverse cardiovascular events in patients with ICI-associated myocarditis.


Subject(s)
Myocarditis , Ventricular Function, Left , Humans , Stroke Volume , Myocarditis/chemically induced , Myocarditis/diagnostic imaging , Magnetic Resonance Imaging, Cine , Immune Checkpoint Inhibitors/adverse effects , Prognosis , Retrospective Studies , Contrast Media/adverse effects , Gadolinium , Predictive Value of Tests , Myocardium
15.
AJR Am J Roentgenol ; 219(2): 199-211, 2022 08.
Article in English | MEDLINE | ID: mdl-35293232

ABSTRACT

BACKGROUND. Coronary MRA is commonly performed at 1.5 T using SSFP acquisitions. Coronary MRA performed at 3 T using SSFP is limited due to impaired fat suppression and has been typically investigated using contrast-enhanced techniques. A Dixon fat-water separation gradient-recalled echo (GRE) method may enable high-quality unenhanced 3-T coronary MRA. OBJECTIVE. The purpose of this study was to compare 1.5-T SSFP and 3-T Dixon water-fat separation GRE methods for unenhanced whole-heart coronary MRA in patients with suspected coronary artery disease (CAD). METHODS. This prospective study included 44 patients (27 men and 17 women; mean age, 59 ± 8 [SD] years) with an intermediate to high risk of CAD who underwent both 1.5-T SSFP and 3-T Dixon GRE coronary MRA examinations before undergoing coronary angiography (CAG). Two radiologists independently assessed coronary arteries in terms of subjective image quality (on a scale of 1-5, with 5 denoting the highest image quality), number of visible segments, apparent contrast-to-noise ratio (CNR; vs myocardium), and presence of significant stenoses. Methods were compared using the mean of the readers' values for apparent CNR and using consensus interpretations for other measures. CAG served as the reference standard for detecting the presence of stenoses. RESULTS. Expressed as a kappa coefficient, interobserver agreement was 0.85 for image quality, 0.85 for segment visibility, and 0.83 for stenosis, and expressed as an intraclass correlation coefficient, interobserver agreement was 0.92 for apparent CNR. The mean overall image quality score was 4.0 ± 1.1 for 3-T Dixon GRE versus 3.0 ± 1.2 for 1.5-T SSFP. The percentage of visible segments for 3-T Dixon GRE versus 1.5-T SSFP was 96.7% versus 88.9% for all segments, 96.9% versus 90.1% for distal segments, and 93.1% versus 77.2% for branch segments. The mean overall apparent CNR was 93.2 ± 29.2 for 3-T Dixon GRE versus 80.8 ± 27.9 for 1.5-T SSFP. The 3-T Dixon GRE method, compared with the 1.5-T SSFP method, showed higher sensitivity and specificity in per-vessel analysis (87.9% vs 77.3% and 83.3% vs 60.6%, respectively), per-segment analysis (84.6% vs 74.8% and 90.9% vs 79.6%, respectively), and per-segment analysis of distal and branch segments (89.7% vs 75.9% and 89.7% vs 73.7%, respectively). CONCLUSION. For unenhanced coronary MRA, 3-T unenhanced Dixon GRE had better image quality and diagnostic performance than 1.5-T SSFP, particularly for distal and branch segments. CLINICAL IMPACT. The 3-T Dixon GRE technique may be preferred to the current clinical standard of the 1.5-T SSFP technique for unenhanced coronary MRA.


Subject(s)
Contrast Media , Magnetic Resonance Angiography , Aged , Constriction, Pathologic , Coronary Angiography , Female , Humans , Magnetic Resonance Angiography/methods , Male , Middle Aged , Prospective Studies , Sensitivity and Specificity , Water
16.
J Opt Soc Am A Opt Image Sci Vis ; 39(9): 1616-1620, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-36215629

ABSTRACT

The imaging blur caused by the relative motion between an imaging system and an imaging target can be eliminated by a compensation operation based on the motion law, although it is invalid when the movement is random. In this paper, the influence of the random jitter on imaging resolution is investigated quantitatively in a computational ghost imaging system, and the maximum of random-jitter amplitude that the system can allow is analyzed. The numerical and experimental results verify our conclusion, and the error between the experiment and simulation is less than 12%. The main reason for the error is the disturbance of experimental noise. By using ghost imaging algorithms to reduce the corresponding impact, this error can be further reduced to 6%.

17.
Radiology ; 301(3): 593-601, 2021 12.
Article in English | MEDLINE | ID: mdl-34546127

ABSTRACT

Background The long-term prognostic value of coronary CT angiography (CCTA) in asymptomatic adults with hepatic steatosis (HS) remains unknown. Purpose To evaluate the long-term prognostic value of CCTA in asymptomatic adults with HS. Materials and Methods Between January 2009 and December 2013, consecutive asymptomatic adults who underwent CCTA evaluation and unenhanced abdominal CT were prospectively enrolled. All participants were divided into two groups-with HS and without HS according to abdominal CT results. The primary end point was major adverse cardiovascular events (MACEs), defined as cardiac death, stroke, myocardial infarction, and angina requiring hospitalization. Multivariable Cox regression analysis and Kaplan-Meier analysis were used to compare survival rates. Results One thousand thirteen participants with HS and 1940 participants without HS who completed the follow-up were included (mean age, 66 years ± 10 [standard deviation] [range, 29-90 years]; 1940 men). During a median of 7.2 years of follow-up (interquartile range, 6.3-8.1), MACEs were observed in 96 of 1013 participants with HS (10%), whereas 80 of 1940 participants without HS (4%) had MACEs. In participants with a Coronary Artery Disease Reporting and Data System (CAD-RADS) category of 0, both participants with and without HS had a similar 8.8-year event-free survival rate (99.2% event-free survival rate in participants with HS vs 99.0% event-free survival rate in participants without HS, P = .77). As for participants with CAD-RADS categories 1 or 2 or 3-5, the 8.8-year event-free survival rate was lower in participants with HS than in those without HS (70.6% vs 85.2%, P < .001; 51.4% vs 71.7%, P = .03, respectively). The risk of MACEs was higher for participants with HS than for those without HS in CAD-RADS categories 1 and 2 (adjusted hazard ratio = 2.3; 95% CI: 1.4, 3.9; P < .001) and CAD-RADS categories 3-5 (adjusted HR = 2.1; 95% CI: 1.2, 3.6; P = .006) but not in the setting of CAD-RADS category 0 (adjusted HR = 5.1; 95% CI: 0.1, 398; P = .47). Conclusion Asymptomatic participants with hepatic steatosis (HS) had a worse prognosis than those without HS in the presence of coronary artery disease (CAD) at coronary CT angiography, whereas participants with HS and without CAD might have excellent clinical outcomes during a median follow-up of 7.2 years. © RSNA, 2021 Online supplemental material is available for this article.


Subject(s)
Computed Tomography Angiography/methods , Coronary Angiography/methods , Coronary Artery Disease/complications , Coronary Artery Disease/diagnostic imaging , Fatty Liver/complications , Adult , Aged , Aged, 80 and over , Coronary Artery Disease/physiopathology , Fatty Liver/physiopathology , Female , Follow-Up Studies , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Predictive Value of Tests , Prognosis , Prospective Studies , Risk Assessment , Risk Factors , Severity of Illness Index
18.
J Magn Reson Imaging ; 53(1): 51-60, 2021 01.
Article in English | MEDLINE | ID: mdl-32798304

ABSTRACT

BACKGROUND: Myocardial strain for assessment of hypertrophic cardiomyopathy (HCM) is of importance and may play a role in identifying obstruction in HCM patients. PURPOSE: To evaluate the utility of myocardial strain for detecting left ventricular (LV) outflow tract (LVOT) obstruction in HCM patients based on magnetic resonance tissue tracking. STUDY TYPE: Retrospective. POPULATION: In all, 44 adult HCM patients with LVOT obstruction and 108 adult HCM patients without LVOT obstruction. FIELD STRENGTH/SEQUENCE: 1.5 T; Steady-state free-precession cine sequence; phase-sensitive inversion-prepared segmented gradient echo sequence for late gadolinium enhancement (LGE) imaging. ASSESSMENT: Strain parameters including the local and global levels of LV myocardium and the subtraction (Sub) of myocardial strain variables between interventricular septal segments (IVSS) and noninterventricular septal segments (NIVSS) were measured for differentiating HCM with obstruction from nonobstruction. Average and maximum LV wall thickness (Average and Maximum LVWT) were also analyzed. STATISTICAL TESTS: Univariate and multivariate logistic regression analysis, area under the receiver operating characteristic (ROC) curve (AUC), intraclass correlation coefficient. RESULTS: In multivariate analysis, Average LVWT, Maximum LVWT, and the subtraction of radial peak strain (Sub Radial PS) between NIVSS and IVSS were independently associated with LVOT obstruction. The AUCs were 0.731, 0.840, and 0.890 for Average LVWT, Maximum LVWT, and Sub Radial PS, respectively. Sub Radial PS (cutoff value: 8.1%) demonstrated the highest sensitivity of 75.0% and a high specificity of 87.9% for identifying LVOT; Maximum LVWT (cutoff value: 22.9 mm) showed good sensitivity (72.7%) and specificity (83.3%). Combining Maximum LVWT >22.9 mm and Sub Radial PS > 8.1% achieved a better diagnostic performance (specificity 95.4%, sensitivity 70.5%). DATA CONCLUSION: Combining Maximum LVWT >22.9 mm and Sub Radial PS >8.1% holds promise for objectively evaluating LVOT obstruction in HCM patients with very high specificity and acceptable sensitivity. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2.


Subject(s)
Cardiomyopathy, Hypertrophic , Ventricular Outflow Obstruction , Adult , Cardiomyopathy, Hypertrophic/diagnostic imaging , Contrast Media , Gadolinium , Humans , Magnetic Resonance Imaging, Cine , Myocardium , Retrospective Studies , Ventricular Outflow Obstruction/diagnostic imaging
19.
Gastrointest Endosc ; 94(1): 91-100.e2, 2021 07.
Article in English | MEDLINE | ID: mdl-33359435

ABSTRACT

BACKGROUND AND AIMS: We sought to compare the efficacy and safety between endoscopic radiofrequency ablation (RFA) and stent placement alone in patients with unresectable extrahepatic biliary cancer (EBC). METHODS: In this randomized controlled trial, patients with locally advanced or metastatic cholangiocarcinoma (CCA) or ampullary cancer who were unsuitable for surgery were recruited from 3 tertiary centers. Eligible patients were randomly assigned to RFA plus plastic stent placement (RFA group) or plastic stent placement alone (stent placement alone group) in a 1:1 ratio. Both groups underwent 2 scheduled interventions with an interval of approximately 3 months. The primary outcome was overall survival (OS). RESULTS: Altogether, 174 participants completed the 2 index endoscopic interventions. No significant differences in baseline characteristics were noted between the 2 groups. The median OS was significantly higher in the RFA group (14.3 vs 9.2 months; hazard ratio, .488; 95% confidence interval, .351-.678; P < .001). A survival benefit was also shown in patients with CCA (13.3 vs 9.2 months; hazard ratio, .546; 95% confidence interval, .386-.771; P < .001). However, no significant between-group differences were found in jaundice control or stent patency duration. The postprocedural Karnofsky performance scores were significantly higher in the RFA group until 9 months (all P < .001). Adverse events were comparable between the 2 groups (27.6% vs 19.5%, P = .211), except for acute cholecystitis, which was more frequently observed in the RFA group (9 vs 0, P = .003). CONCLUSIONS: Compared with stent placement alone, additional RFA may improve OS and quality of life of patients with inoperable primary EBC who do not undergo systemic treatments. (Clinical trial registration number: NCT01844245.).


Subject(s)
Ampulla of Vater , Bile Duct Neoplasms , Catheter Ablation , Common Bile Duct Neoplasms , Radiofrequency Ablation , Ampulla of Vater/surgery , Bile Duct Neoplasms/surgery , Bile Ducts, Intrahepatic , Humans , Plastics , Quality of Life , Stents , Treatment Outcome
20.
Langmuir ; 37(22): 6830-6837, 2021 Jun 08.
Article in English | MEDLINE | ID: mdl-34043914

ABSTRACT

The heterointeraction between liquid drops and air bubbles dispersed in another immiscible liquid is studied with the application of the atomic force microscopy (AFM) probe techniques. The tetradecane drops and air bubbles readily coalescence to form a lens-like structure in 100 mM sodium chloride aqueous solution, demonstrating strong hydrophobic (HB) attraction. The interaction range and strength of this hydrophobic attraction between oil drops and air bubbles is investigated by fine control of electrical double layer thicknesses related to specific electrolyte concentrations, and a midrange term in combination with a short-range term is found to present a proper characterization of this hydrophobic attraction. A further step is taken by introducing a triblock copolymer (Pluronic F68) into the aqueous solution, with results indicating that a relatively long-range steric hindrance (SH) furnished by a polymer "brush" surmounts the hydrophobic attraction. Finally, the interaction between a water drop and an air bubble in tetradecane is also measured as a comparison. The repelling action between a hydrophobic body (air bubble) and water drop indicates a strong repulsion. The present results show an interesting understanding of hydrophobic interactions between drops and bubbles, which is of potential application in controlling dispersion stability.

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