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Background: The use of native T1 mapping for evaluation of hypertrophic cardiomyopathy (HCM) is being explored, and its combination with histogram analysis may benefit the accuracy of such assessments.Purpose: To investigate the relationship of segmental left ventricular wall thickness (LVWT), myocardial fibrosis, and strain parameters with segmental histogram parameters of native T1 mapping in HCM patients.Study Type: Retrospective.Subjects: Ninety-three HCM patients without previous cardiovascular diseases were included.Field Strength/sequence: 3.0T cardiac MR. Steady-state free precession cine imaging, modified Look-Locker inversion recovery, phase-sensitive inversion recovery.Assessment: Images were assessed by three experienced radiologists.Statistical Tests: Mann-Whitney U-tests, area under the curve (AUC), Spearman's rank correlation, intraclass correlation coefficient, and Bland-Altman test were used for statistical analysis.Results: A higher LVWT value correlated with higher means, minimums, 10th /25th /50th /75th /90th percentiles, maximums, kurtosis, entropy, and lower SD and energy of T1 mapping (P < 0.05 for all), with the correlation being stronger for entropy and energy (Spearman's rho = 0.439 and -0.413, respectively) than other parameters. Late gadolinium enhancement positive (LGE+) segments exhibited higher mean, minimum, 10th /25th /50th /75th /90th percentiles, maximum, entropy, and lower energy of T1 times than late gadolinium enhancement negative (LGE-) segments (P < 0.001 for all). Impaired strain function parameters (peak thickening and thickening rate in radial, circumferential, and longitudinal directions) demonstrated a weak correlation with higher entropy (P < 0.001 for all) and lower energy (P < 0.001 for all).Data Conclusion: Histogram parameters of native T1 mapping provide more information than mean T1 times alone. Among these parameters, entropy and energy may correlate better with LVWT, myocardial late gadolinium enhancement, and strain parameters than mean T1 times in HCM patients.Level Of Evidence: 2 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019;49:668-677. [ABSTRACT FROM AUTHOR]

Background: Previous studies have shown that diffusion-weighted imaging (DWI) is sensitive to myocardial fibrosis in ischemic and nonischemic cardiomyopathy.Purpose: To explore the prognostic value of apparent diffusion coefficient (ADC) for detecting myocardial fibrosis and its relationship to the contractile function in hypertrophic cardiomyopathy (HCM).Study Type: Prospective.Population: A total of 45 HCM patients and 20 controls.Field Strength/sequence: 3.0T cardiac MRI. The cardiac MR sequences included cine, T1 mapping, and DWI.Assessment: According to the presence of late gadolinium enhancement (LGE) and the extracellular volume (ECV) values (+2 SD of control subjects), respectively, reader W and reader J assessed the value of ADC of each segment for detecting myocardial fibrosis and its relationship to impaired contractile function in HCM patients.Statistical Tests: Independent sample t-test, Pearson analysis, and intraclass correlation (ICC).Results: The value of ECV was 23.6 ± 3.0% for control. ECV ≥ 29.6% and ECV < 29.6% groups were classified. ADC values in the ECV ≥ 29.6% group were significantly increased compared to the ECV < 29.6% group, (2.41 ± 0.23 μm2 /ms vs. 2.03 ± 0.16 μm2 /ms, P < 0.005). Compared to the LGE - group, ECV (32.1 ± 2.3% vs. 29.0 ± 2.8%, P < 0.005) and ADC (2.60 ± 0.18 μm2 /ms vs. 2.10 ± 0.07 μm2 /ms, P < 0.005) values were significantly increased in the LGE + group. ADC values were linearly associated with ECV values (R2  = 0.65) in HCM patients. ADC values were linearly associated with circumferential and longitudinal strain (R2  = 0.60, R2  = 0.46), as well as circumferential, longitudinal, and radial strain rate (R2  = 0.13, R2  = 0.25, R2  = 0.17, respectively).Data Conclusion: Contractile dysfunction in HCM is predominantly associated with ADC, which is a feasible alternative to ECV and LGE for detecting myocardial fibrosis.Level Of Evidence: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;48:1139-1146. [ABSTRACT FROM AUTHOR]

Background: Acute myocardial infarction (AMI) is a disease with high morbidity and mortality worldwide and the evaluation of myocardial injury and perfusion status following myocardial ischemia and reperfusion is of clinical value. Purpose To assess the diagnostic utility of simplified perfusion fraction (SPF) in differentiating salvage and infarcted myocardium and its predictive value for left ventricular remodeling in patients with reperfusion ST‐segment elevation myocardial infarction (STEMI). Study Type: Prospective. Population Forty‐one reperfused STEMI patients and 20 healthy volunteers. Field Strength/Sequence: 3.0T MRI. The MR examination included cine, T2‐short tau inversion recovery (T2‐STIR), first pass perfusiong (FPP)，phase sensitive inversion recovery (PSIR), and diffusion‐weighted imaging (DWI). Assessment SPF values among different myocardium regions (infarcted, salvaged, remote, and MVO) and stages of reperfused STEMI patients as well as normal controls were measured. The diagnostic utility of SPF values in differentiating salvaged and infarcted myocardium was assessed. Statistical Analysis: Independent t‐test and the Mann–Whitney U‐test. Logistic regression. Results: SPF values in healthy controls were not significantly different than SPF values in the remote myocardium of patients (40.09 ± 1.47% vs. 40.28 ± 1.93%, P = 0.698). In reperfusion STEMI patients, SPF values were lower in infarcted myocardium compared to remote and salvaged myocardium (32.15 ± 2.36% vs. 40.28 ± 1.93%, P < 0.001; 32.15 ± 2.36% vs. 36.68 ± 2.71%, P < 0.001). SPF values of infarcted myocardium showed a rebound increase from acute to convalescent stages (32.15 ± 2.36% vs. 34.69 ± 3.69%, P < 0.001). When differentiating infarcted and salvaged myocardium, SPF values demonstrated an area under the curve (AUC) of 0.89 (sensitivity 85.4%, specificity 80.5%, cutoff 34.42%). Lower SPF values were associated with lower odds ratio (OR = 0.304) of left ventricular remodeling after adjusting for potential confounders with a confidence interval (CI) of 0.129–0.717, P = 0.007. Data Conclusion: SPF might be able to differentiate salvaged and infarcted myocardium and is a strong predictor of left ventricular remodeling in reperfused STEMI patients. Level of Evidence 2 Technical Efficacy Stage 2 [ABSTRACT FROM AUTHOR]

Increased fatty acid β-oxidation is essential for early postgerminative growth in seedlings, but high levels of H2O2 produced by β-oxidation can induce oxidative stress. Whether and how catalase (CAT) functions in fine-tuning H2O2 homeostasis during seedling growth remain unclear. Here, we report that CAT2 functions in early seedling growth. Compared to the wild type, the cat2-1 mutant, with elevated H2O2 levels, exhibited reduced root elongation on sucrose (Suc)-free medium, mimicking soils without exogenous sugar supply. Treatment with the H2O2 scavenger potassium iodide rescued the mutant phenotype of cat2-1. In contrast to the wild type, the cat2-1 mutant was insensitive to the CAT inhibitor 3-amino-1,2,4-triazole in terms of root elongation when grown on Suc-free medium, suggesting that CAT2 modulates early seedling growth by altering H2O2 accumulation. Furthermore, like cat2-1, the acyl-CoA oxidase (ACX) double mutant acx2-1 acx3-6 showed repressed root elongation, suggesting that CAT2 functions in early seedling growth by regulating ACX activity, as this activity was inhibited in cat2-1. Indeed, decreased ACX activity and short root of cat2-1 seedlings grown on Suc-free medium were rescued by overexpressing ACX3. Together, these findings suggest that CAT2 functions in early seedling growth by scavenging H2O2 and stimulating ACX2/3 activity. [ABSTRACT FROM AUTHOR]

In this study, low-field nuclear magnetic resonance(LF-NMR) and magnetic resonance imaging(MRI) were employed to analyze the water distribution, status, and migration in the moistening process of Arecae Semen. Peleg model was adopted to study the water absorption kinetics of Arecae Semen moistened at different water temperatures(10, 30, and 50 ℃). The Arecae Semen samples soaked at different water temperatures all contained four water states: binding water T&#95;(21), non-flowing water T&#95;(22), free water T&#95;(23), and unbound water T&#95;(24). Non-flowing water had the largest increase in peak area during the moistening process, followed by free water. The peak areas of non-flowing water, free water, and total water were correlated with the water content(P&lt;0.01). Therefore, LF-NMR can quickly and non-destructively predict the water content of Arecae Semen during moistening. The peak area of non-flowing water and the content of free water were correlated with the content of arecoline in the soaking solution(P&lt;0.01), which indicated that the faster flow of non-flowing water and more free water corresponded to more arecoline dissolved. The MRI images showed that the water migration pathway varied at different soaking temperatures, and the moistening degree obtained by this means was consistent with that obtained based on traditional experience. The rate constant K&#95;1 fitted by Peleg model decreased with the increase in water temperature, while the capacity constant K&#95;2 showed an opposite trend. The Arrhenius equation fitting of K&#95;1 with temperature showed that the activation energy of Arecae Semen in the moistening process was 32.98 kJ·mol~(-1). LF-NMR/MRI can be used to analyze the water status and content and determine the end moisturing point of Arecae Semen. Peleg model can accurately describe the water absorption properties of Arecae Semen in the moistening process. The findings of this study can guide the moistening optimization and mechanism research of other seed Chinese medicinal materials.

Background: The use of native T 1 mapping for evaluation of hypertrophic cardiomyopathy (HCM) is being explored, and its combination with histogram analysis may benefit the accuracy of such assessments., Purpose: To investigate the relationship of segmental left ventricular wall thickness (LVWT), myocardial fibrosis, and strain parameters with segmental histogram parameters of native T 1 mapping in HCM patients., Study Type: Retrospective., Subjects: Ninety-three HCM patients without previous cardiovascular diseases were included., Field Strength/sequence: 3.0T cardiac MR. Steady-state free precession cine imaging, modified Look-Locker inversion recovery, phase-sensitive inversion recovery., Assessment: Images were assessed by three experienced radiologists., Statistical Tests: Mann-Whitney U-tests, area under the curve (AUC), Spearman's rank correlation, intraclass correlation coefficient, and Bland-Altman test were used for statistical analysis., Results: A higher LVWT value correlated with higher means, minimums, 10 th /25 th /50 th /75 th /90 th percentiles, maximums, kurtosis, entropy, and lower SD and energy of T 1 mapping (P < 0.05 for all), with the correlation being stronger for entropy and energy (Spearman's rho = 0.439 and -0.413, respectively) than other parameters. Late gadolinium enhancement positive (LGE+) segments exhibited higher mean, minimum, 10 th /25 th /50 th /75 th /90 th percentiles, maximum, entropy, and lower energy of T 1 times than late gadolinium enhancement negative (LGE-) segments (P < 0.001 for all). Impaired strain function parameters (peak thickening and thickening rate in radial, circumferential, and longitudinal directions) demonstrated a weak correlation with higher entropy (P < 0.001 for all) and lower energy (P < 0.001 for all)., Data Conclusion: Histogram parameters of native T 1 mapping provide more information than mean T 1 times alone. Among these parameters, entropy and energy may correlate better with LVWT, myocardial late gadolinium enhancement, and strain parameters than mean T 1 times in HCM patients., Level of Evidence: 2 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019;49:668-677., (© 2018 International Society for Magnetic Resonance in Medicine.)

Increased fatty acid β-oxidation is essential for early postgerminative growth in seedlings, but high levels of H 2 O 2 produced by β-oxidation can induce oxidative stress. Whether and how catalase (CAT) functions in fine-tuning H 2 O 2 homeostasis during seedling growth remain unclear. Here, we report that CAT2 functions in early seedling growth. Compared to the wild type, the cat2-1 mutant, with elevated H 2 O 2 levels, exhibited reduced root elongation on sucrose (Suc)-free medium, mimicking soils without exogenous sugar supply. Treatment with the H 2 O 2 scavenger potassium iodide rescued the mutant phenotype of cat2-1. In contrast to the wild type, the cat2-1 mutant was insensitive to the CAT inhibitor 3-amino-1,2,4-triazole in terms of root elongation when grown on Suc-free medium, suggesting that CAT2 modulates early seedling growth by altering H 2 O 2 accumulation. Furthermore, like cat2-1, the acyl-CoA oxidase (ACX) double mutant acx2-1 acx3-6 showed repressed root elongation, suggesting that CAT2 functions in early seedling growth by regulating ACX activity, as this activity was inhibited in cat2-1. Indeed, decreased ACX activity and short root of cat2-1 seedlings grown on Suc-free medium were rescued by overexpressing ACX3. Together, these findings suggest that CAT2 functions in early seedling growth by scavenging H 2 O 2 and stimulating ACX2/3 activity., (© 2017 John Wiley & Sons Ltd.)