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We present the first example of an 99TcO4- anion entrapped within the cavity of a silver cluster, revealing an unprecedented photoinduced charge transfer phenomenon. [Ag24(C≡CtBu)20(99TcO4)]·(BF4)3 (denoted as 99TcO4-@Ag24) was successfully synthesized and structurally characterized. Single-crystal X-ray diffraction and Raman spectroscopy reveal that the tetrahedral structure of the 99TcO4- anion sustains significant symmetry breaking with weakened Tc-O bond strength under confinement within the Ag24(C≡CtBu)204+ cluster. Notably, 99TcO4-@Ag24 exhibits a broadband electronic absorption spectrum in the visible region, which was absent for the other 99TcO4--containing compounds. Density functional theory calculations elucidate that host-guest electrostatic interactions result in an electron polarization effect between the 99TcO4- anion core and the Ag24 cationic shell. The emergence of an absorption band in 99TcO4-@Ag24 is rationalized by intermolecular charge transfer from the Ag24 electronic states to the lowest unoccupied molecular orbitals of 99TcO4- instead of the intramolecular electron transition observed in other 99TcO4--containing compounds.
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OBJECTIVE: Myocardial fibrosis occurs in the early subclinical stage of cardiac involvement in idiopathic inflammatory myopathies (IIMs). Soluble suppression of tumorigenicity 2 (sST2) is known to have an immunomodulatory impact during autoimmune disease development. The current study investigated the diagnostic value of sST2 for myocardial fibrosis during early stage of cardiac involvement in IIM. METHODS: A total of 44 IIM patients with normal heart function and 32 age- and gender-matched healthy controls (HCs) were enrolled. Serum sST2 levels were measured by ELISA and cardiac magnetic resonance (CMR) parameters for myocardial fibrosis [native T1, extracellular volume (ECV), late-gadolinium enhancement (LGE)] and oedema (T2 values) were analysed. RESULTS: IIM patients had significantly higher sST2 levels than HCs [67.5 ng/ml (s.d. 30.4)] vs 14.4 (5.5), P < 0.001] and levels correlated positively with diffuse myocardial fibrosis parameters, native T1 (r = 0.531, P = 0.000), ECV (r = 0.371, P = 0.013) and focal myocardial fibrosis index and LGE (r = 0.339, P = 0.024) by Spearman's correlation analysis. sST2 was an independent predictive factor for diffuse and focal myocardial fibrosis after adjustment for age, gender, BMI and ESR. Risk increased ≈15.4% for diffuse [odds ratio (OR) 1.154 (95% CI 1.021, 1.305), P = 0.022] and 3.8% for focal [OR 1.038 (95% CI 1.006, 1.072), P = 0.020] myocardial fibrosis per unit increase of sST2. Cut-off values for diagnosing diffuse and focal myocardial fibrosis were sST2 ≥51.3 ng/ml [area under the curve (AUC) = 0.942, sensitivity = 85.7%, specificity = 98.9%, P < 0.001] and 53.3 ng/ml (AUC = 0.753, sensitivity = 87.5%, specificity = 58.3%, P < 0.01), respectively. CONCLUSION: sST2 showed a marked elevation during the subclinical stage of cardiac involvement in IIM and has potential as a biomarker for predicting diffuse and focal myocardial fibrosis in IIM.
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Cardiomiopatias , Miosite , Humanos , Meios de Contraste , Gadolínio , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/etiologia , FibroseRESUMO
BACKGROUND: The impact of the coexistence of type 2 diabetes mellitus (T2DM) in patients with non-ischemic dilated cardiomyopathy (DCM) on clinical profiles, myocardial fibrosis, and outcomes remain incompletely understood. METHOD: A total of 1152 patients diagnosed with non-ischemic DCM were prospectively enrolled from June 2012 to October 2021 and categorized into T2DM and non-T2DM groups. Clinical characteristics, cardiac function, and myocardial fibrosis evaluated by CMR were compared between the two groups. The primary endpoint included both all-cause mortality and heart transplantation. Cause of mortality was classified into heart failure death, sudden cardiac death, and non-cardiac death. Cox regression analysis and Kaplan-Meier analysis were performed to identify the association between T2DM and clinical outcomes. Propensity score matching (PSM) cohort including 438 patients was analyzed to reduce the bias from confounding covariates. RESULTS: Among the 1152 included DCM patients, 155 (13%) patients had T2DM. Patients with T2DM were older (55 ± 12 vs. 47 ± 14 years, P < 0.001), had higher New York Heart Association (NYHA) functional class (P = 0.003), higher prevalence of hypertension (37% vs. 21%, P < 0.001), atrial fibrillation (31% vs. 16%, P < 0.001), lower left ventricular (LV) ejection fraction (EF) (23 ± 9% vs. 27 ± 12%, P < 0.001), higher late gadolinium enhancement (LGE) presence (55% vs. 45%, P = 0.02), and significantly elevated native T1 (1323 ± 81ms vs. 1305 ± 73ms, P = 0.01) and extracellular volume fraction (ECV) (32.7 ± 6.3% vs. 31.3 ± 5.9%, P = 0.01) values. After a median follow-up of 38 months (interquartile range: 20-57 months), 239 patients reached primary endpoint. Kaplan-Meier analysis showed that patients with T2DM had worse clinical outcomes compared with those without T2DM in the overall cohort (annual events rate: 10.2% vs. 5.7%, P < 0.001). T2DM was independently associated with an increased risk of primary endpoint in the overall (Hazard ratio [HR]: 1.61, 95% CI: 1.13-2.33, P = 0.01) and PSM (HR: 1.54, 95% CI: 1.05-2.24, P = 0.02) cohorts. Furthermore, T2DM was associated with a higher risk of heart failure death (P = 0.006) and non-cardiac death (P = 0.02), but not sudden cardiac death (P = 0.16). CONCLUSIONS: Patients with T2DM represented a more severe clinical profile and experienced more adverse outcomes compared to those without T2DM in a large DCM cohort. TRIAL REGISTRATION: Trial registration number: ChiCTR1800017058; URL: https://www. CLINICALTRIALS: gov .
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Cardiomiopatia Dilatada , Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Humanos , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/complicações , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Meios de Contraste , Estudos Prospectivos , Imagem Cinética por Ressonância Magnética/efeitos adversos , Gadolínio , Prognóstico , Volume Sistólico , Fibrose , Insuficiência Cardíaca/diagnóstico , Valor Preditivo dos TestesRESUMO
BACKGROUND: Hepatic alterations are common aftereffects of heart failure (HF) and ventricular dysfunction. The prognostic value of liver injury markers derived from cardiac MRI studies in nonischemic dilated cardiomyopathy (DCM) patients is unclear. PURPOSE: Evaluate the prognostic performance of liver injury markers derived from cardiac MRI studies in DCM patients. STUDY TYPE: Prospective. POPULATION: Three hundred fifty-six consecutive DCM patients diagnosed according to ESC guidelines (age 48.7 ± 14.2 years, males 72.6%). FIELD STRENGTH/SEQUENCE: Steady-state free precession, modified Look-Locker inversion recovery T1 mapping and phase sensitive inversion recovery late gadolinium enhancement (LGE) sequences at 3 T. ASSESSMENT: Clinical characteristics, conventional MRI parameters (ventricular volumes, function, mass), native myocardial and liver T1, liver extracellular volume (ECV), and myocardial LGE presence were assessed. Patients were followed up for a median duration of 48.3 months (interquartile range 42.0-69.9 months). Primary endpoints included HF death, sudden cardiac death, heart transplantation, and HF readmission; secondary endpoints included HF death, sudden cardiac death, and heart transplantation. Models were developed to predict endpoints and the incremental value of including liver parameters assessed. STATISTICAL TESTS: Optimal cut-off value was determined using receiver operating characteristic curve and Youden method. Survival analysis was performed using Kaplan-Meier and Cox proportional hazard. Discriminative power of models was compared using net reclassification improvement and integrated discriminatory index. P value <0.05 was considered statistically significant. RESULTS: 47.2% patients reached primary endpoints; 25.8% patients reached secondary endpoints. Patients with elevated liver ECV (cut-off 34.4%) had significantly higher risk reaching primary and secondary endpoints. Cox regression showed liver ECV was an independent prognostic predictor, and showed independent prognostic value for primary endpoints and long-term HF readmission compared to conventional clinical and cardiac MRI parameters. DATA CONCLUSIONS: Liver ECV is an independent prognostic predictor and may serve as an innovative approach for risk stratification for DCM. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.
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Cardiomiopatia Dilatada , Fígado , Imageamento por Ressonância Magnética , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Cardiomiopatia Dilatada/diagnóstico por imagem , Prognóstico , Estudos Prospectivos , Adulto , Fígado/diagnóstico por imagem , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Meios de Contraste , Gadolínio , Miocárdio/patologia , Coração/diagnóstico por imagem , BiomarcadoresRESUMO
BACKGROUND: Magnetic resonance imaging (MRI) reference ranges for ventricular morphology and function in the Chinese population are lacking. PURPOSE: To establish the MRI reference ranges of left and right ventricular (LV and RV) morphology and function based on a large multicenter cohort. STUDY TYPE: Prospective. POPULATION: One thousand and twelve healthy Chinese Han adults. FIELD STRENGTH/SEQUENCE: Balanced steady-state free procession cine sequence at 3.0 T. ASSESSMENT: Biventricular end-diastolic, end-systolic, stroke volume, and ejection fraction (EDV, ESV, SV, and EF), LV mass (LVM), end-diastolic and end-systolic dimension (LVEDD and LVESD), anteroseptal wall thickness (AS), and posterolateral wall thickness (PL) were measured. Body surface area (BSA) and height were used to index biventricular parameters. Parameters were compared between age groups and sex. STATISTICAL TESTS: Independent-samples t-tests or Mann-Whitney U test to compare mean values between sexes; ANOVA or Kruskal-Wallis test to compare mean values among age groups; linear regression to assess the relationships between cardiac parameters and age (correlation coefficient, r). A P value <0.05 was considered statistically significant. RESULTS: The biventricular volumes, LVM, LVEDD, RVEDV/LVEDV ratio, LVESD, AS, and PL were significantly greater in males than in females, even after indexing to BSA or height, while LVEF and RVEF were significantly lower in males than in females. For both sexes, age was significantly negatively correlated with biventricular volumes (male and female: LVEDV [r = -0.491; r = -0.373], LVESV [r = -0.194; r = -0.184], RVEDV [r = -0.639; r = -0.506], RVESV [r = -0.270; r = -0.223]), with similar correlations after BSA normalization. LVEF (r = 0.043) and RVEF (r = 0.033) showed a significant correlation with age in females, but not in males (P = 0.889; P = 0.282). DATA CONCLUSION: MRI reference ranges for biventricular morphology and function in Chinese adults are presented and show significant associations with age and sex. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.
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Ventrículos do Coração , Imageamento por Ressonância Magnética , Adulto , Humanos , Masculino , Feminino , Volume Sistólico , Valores de Referência , Estudos Prospectivos , Imageamento por Ressonância Magnética/métodos , China , Função Ventricular Esquerda , Função Ventricular DireitaRESUMO
BACKGROUND AND PURPOSE: This study aimed to investigate the association between iron content in grey matter (GM) nuclei and functional outcome in acute ischaemic stroke (AIS) patients utilizing quantitative susceptibility mapping. METHODS: Forty AIS patients and 40 age-, sex- and education-matched healthy controls underwent quantitative susceptibility mapping to assess susceptibility values, which are positively correlated with iron content, in the caudate nucleus, putamen, globus pallidus, thalamus, red nucleus and substantia nigra. The nuclei on the contralateral side were measured in AIS patients to minimize confounding due to oedema or haemorrhage. Functional outcome was determined by the modified Rankin Scale (mRS) score at 3 months after stroke. Poor outcome was defined as mRS >2, whilst a good outcome was defined as ≤2. RESULTS: Susceptibility values were significantly higher in most contralateral GM nuclei in AIS patients than in the corresponding left or right nuclei in healthy controls. AIS patients with poor outcome showed significantly lower susceptibility value than those with good outcome in the contralateral caudate nucleus, but no significant differences were observed in other GM nuclei. Binary logistic regression analysis revealed a significant association between the susceptibility value of the contralateral caudate nucleus and poor outcome after adjustment for confounders (adjusted odds ratio 0.692, 95% confidence interval 0.486-0.986, p = 0.042). Receiver operating characteristic curve analysis showed an acceptable ability of the susceptibility value of the contralateral caudate nucleus to predict poor outcome (area under the curve 0.740, p = 0.013). CONCLUSIONS: Lower iron content in the contralateral caudate nucleus was associated with poor functional outcome in AIS patients.
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BACKGROUND: The prognostic value of follow-up cardiovascular magnetic resonance (CMR) in dilated cardiomyopathy (DCM) patients is unclear. We aimed to investigate the prognostic value of cardiac function, structure, and tissue characteristics at mid-term CMR follow-up. METHODS: The study population was a prospectively enrolled cohort of DCM patients who underwent guideline-directed medical therapy with baseline and follow-up CMR, which included measurement of biventricular volume and ejection fraction, late gadolinium enhancement, native T1, native T2, and extracellular volume. During follow-up, major adverse cardiac events (MACE) were defined as a composite endpoint of cardiovascular death, heart transplantation, and heart-failure readmission. RESULTS: Among 235 DCM patients (median CMR interval: 15.3 months; interquartile range: 12.5-19.2 months), 54 (23.0%) experienced MACE during follow-up (median: 31.2 months; interquartile range: 20.8-50.0 months). In multivariable Cox regression, follow-up CMR models showed significantly superior predictive value than baseline CMR models. Stepwise multivariate Cox regression showed that follow-up left ventricular ejection fraction (LVEF; hazard ratio [HR], 0.93; 95% confidence interval [CI], 0.91-0.96; p < 0.001) and native T1 (HR, 1.01; 95% CI, 1.00-1.01; p = 0.030) were independent predictors of MACE. Follow-up LVEF ≥ 40% or stable LVEF < 40% with T1 ≤ 1273 ms indicated low risk (annual event rate < 4%), while stable LVEF < 40% and T1 > 1273 ms or LVEF < 40% with deterioration indicated high risk (annual event rate > 15%). CONCLUSIONS: Follow-up CMR provided better risk stratification than baseline CMR. Improvements in the LVEF and T1 mapping are associated with a lower risk of MACE.
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Cardiomiopatia Dilatada , Transplante de Coração , Imagem Cinética por Ressonância Magnética , Valor Preditivo dos Testes , Volume Sistólico , Função Ventricular Esquerda , Humanos , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/fisiopatologia , Cardiomiopatia Dilatada/mortalidade , Masculino , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , Fatores de Tempo , Fatores de Risco , Medição de Risco , Adulto , Idoso , Prognóstico , Readmissão do Paciente , Remodelação Ventricular , Progressão da DoençaRESUMO
Amine ligands have been widely applied as morphology-directing reagents in nanostructure synthesis. In this work, we explored the application of the amine ligands in the active surface growth mechanism in place of the strong thiolated ligands. Despite being weaker compared to the thiols, amine ligands such as aniline were also shown to be capable of facilitating the template-less electrodeposition of Au nanowires (NWs) on the substrate via the active surface growth mechanism. Given the close binding difference between the amine-grafted substrate and the ligands, substrate functionalization becomes critically important for effective construction of the active surface and the growth of the nanowires. Additionally, the growth with the amine ligands took place at more positive reduction potentials and is less prone to splitting and bundle formation. A systematic generality study revealed that besides the aromatic amines, long-chain aliphatic amines were also capable of facilitating nanowire growth. Given the weak binding affinity of the amine ligands, the Au NWs are readily accessible for further processing to generate sophisticated one-dimensional structures. As a demonstration, tandem electrodeposition was performed to directly obtain coaxial core-shell Au@Pt NWs with adjustable length, diameter, and shell thickness.
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OBJECTIVES: Older adults often complain of difficulty in communicating in noisy environments. Contextual information is considered an important cue for identifying everyday speech. To date, it has not been clear exactly how context use (CU) and reliance on context in older adults are affected by hearing status and cognitive function. The present study examined the effects of semantic context on the performance of speech recognition, recall, perceived listening effort (LE), and noise tolerance, and further explored the impacts of hearing loss and working memory capacity on CU and reliance on context among older adults. DESIGN: Fifty older adults with normal hearing and 56 older adults with mild-to-moderate hearing loss between the ages of 60 and 95 years participated in this study. A median split of the backward digit span further classified the participants into high working memory (HWM) and low working memory (LWM) capacity groups. Each participant performed high- and low-context Repeat and Recall tests, including a sentence repeat and delayed recall task, subjective assessments of LE, and tolerable time under seven signal to noise ratios (SNRs). CU was calculated as the difference between high- and low-context sentences for each outcome measure. The proportion of context use (PCU) in high-context performance was taken as the reliance on context to explain the degree to which participants relied on context when they repeated and recalled high-context sentences. RESULTS: Semantic context helps improve the performance of speech recognition and delayed recall, reduces perceived LE, and prolongs noise tolerance in older adults with and without hearing loss. In addition, the adverse effects of hearing loss on the performance of repeat tasks were more pronounced in low context than in high context, whereas the effects on recall tasks and noise tolerance time were more significant in high context than in low context. Compared with other tasks, the CU and PCU in repeat tasks were more affected by listening status and working memory capacity. In the repeat phase, hearing loss increased older adults' reliance on the context of a relatively challenging listening environment, as shown by the fact that when the SNR was 0 and -5 dB, the PCU (repeat) of the hearing loss group was significantly greater than that of the normal-hearing group, whereas there was no significant difference between the two hearing groups under the remaining SNRs. In addition, older adults with LWM had significantly greater CU and PCU in repeat tasks than those with HWM, especially at SNRs with moderate task demands. CONCLUSIONS: Taken together, semantic context not only improved speech perception intelligibility but also released cognitive resources for memory encoding in older adults. Mild-to-moderate hearing loss and LWM capacity in older adults significantly increased the use and reliance on semantic context, which was also modulated by the level of SNR.
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Surdez , Perda Auditiva , Percepção da Fala , Humanos , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Memória de Curto Prazo , AudiçãoRESUMO
Individuals with methamphetamine use disorder (MUD) often experience anxiety and depressive symptoms during abstinence, which can worsen the likelihood of relapse. Thus, it is essential to understand the neuro-mechanism behind methamphetamine use and its associated emotional withdrawal symptoms in order to develop effective clinical strategies. This study aimed to evaluate associations between emotional withdrawal symptoms and structural covariance networks (SCNs) based on cortical thickness (CTh) across the brain. The CTh measures were obtained from Tl-weighted MRI data from a sample of 48 males with MUD during abstinence and 48 male healthy controls. The severity of anxiety and depressive symptoms was assessed by the Hamilton Anxiety Scale (HAMA) and depression (HAMD) scales. Two important nodes belonging to the brain reward system, the right rostral anterior cingulate cortex (rACC) and medial prefrontal cortex (medPFC), were selected as seeds to conduct SCNs and modulation analysis by emotional symptoms. MUDs showed higher structural covariance between the right rACC and regions in the dorsal attention, right frontoparietal, auditory, visual and limbic networks. They also displayed higher structural covariance between the right medPFC and regions in the limbic network. Moreover, the modulation analysis showed that higher scores on HAMA were associated with increased covariance between the right rACC and the left parahippocampal and isthmus cingulate cortex in the default mode network. These outcomes shed light on the complex neurobiological mechanisms underlying methamphetamine use and its associated emotional withdrawal symptoms and may provide new insights into the development of effective treatments for MUD.
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Emoções , Síndrome de Abstinência a Substâncias , Humanos , Masculino , Encéfalo/diagnóstico por imagem , Ansiedade/diagnóstico por imagem , Imageamento por Ressonância Magnética , Mapeamento Encefálico , Síndrome de Abstinência a Substâncias/diagnóstico por imagemRESUMO
One novel compound, (R)-3, 6-diethoxy-4-hydroxycyclohex-3-en-1-one (1) and thirteen known compounds were isolated from the waste tobacco leaves. The structures of two compounds (1-2) were confirmed and attributed firstly by the extensive spectroscopic data, including 1D/2D NMR, IR, HR-ESI-MS, CD, and ECD spectra. Notably, seven compounds (2, 3, 9, 10, 11, 12, and 13) exhibited better tyrosinase inhibitory activity than the positive control kojic acid. The binding modes of these compounds revealed that their structure formed strong hydrogen bonds and van der Waals forces with the active sites of tyrosinase. These results indicated that waste tobacco leaves are good resources for developing tyrosinase inhibitors.
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Inibidores Enzimáticos , Monofenol Mono-Oxigenase , Nicotiana , Folhas de Planta , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Folhas de Planta/química , Nicotiana/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/isolamento & purificação , Estrutura Molecular , Relação Estrutura-Atividade , Simulação de Acoplamento MolecularRESUMO
Background Sudden cardiac death (SCD) is one of the leading causes of death in individuals with nonischemic dilated cardiomyopathy (DCM). However, the risk stratification of SCD events remains challenging in clinical practice. Purpose To determine whether myocardial tissue characterization with cardiac MRI could be used to predict SCD events and to explore a SCD stratification algorithm in nonischemic DCM. Materials and Methods In this prospective single-center study, adults with nonischemic DCM who underwent cardiac MRI between June 2012 and August 2020 were enrolled. SCD-related events included SCD, appropriate implantable cardioverter-defibrillator shock, and resuscitation after cardiac arrest. Competing risk regression analysis and Kaplan-Meier analysis were performed to identify the association of myocardial tissue characterization with outcomes. Results Among the 858 participants (mean age, 48 years; age range, 18-83 years; 603 men), 70 (8%) participants experienced SCD-related events during a median follow-up of 33.0 months. In multivariable competing risk analysis, late gadolinium enhancement (LGE) (hazard ratio [HR], 1.87; 95% CI: 1.07, 3.27; P = .03), native T1 (per 10-msec increase: HR, 1.07; 95% CI: 1.04, 1.11; P < .001), and extracellular volume fraction (per 3% increase: HR, 1.26; 95% CI: 1.11, 1.44; P < .001) were independent predictors of SCD-related events after adjustment of systolic blood pressure, atrial fibrillation, and left ventricular ejection fraction. An SCD risk stratification category was developed with a combination of native T1 and LGE. Participants with a native T1 value 4 or more SDs above the mean (1382 msec) had the highest annual SCD-related events rate of 9.3%, and participants with a native T1 value 2 SDs below the mean (1292 msec) and negative LGE had the lowest rate of 0.6%. This category showed good prediction ability (C statistic = 0.74) and could be used to discriminate SCD risk and competing heart failure risk. Conclusion Myocardial tissue characteristics derived from cardiac MRI were independent predictors of sudden cardiac death (SCD)-related events in individuals with nonischemic dilated cardiomyopathy and could be used to stratify participants according to different SCD risk categories. Clinical trial registration no. ChiCTR1800017058 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Sakuma in this issue.
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Cardiomiopatia Dilatada , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Meios de Contraste , Morte Súbita Cardíaca , Gadolínio , Imageamento por Ressonância Magnética/efeitos adversos , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Volume Sistólico , Função Ventricular EsquerdaRESUMO
BACKGROUND: First-pass perfusion cardiac MR imaging could reflect pulmonary hemodynamics. However, the clinical value of pulmonary transit time (PTT) derived from first-pass perfusion MRI in light-chain (AL) amyloidosis requires further evaluation. PURPOSE: To assess the clinical and prognostic value of PTT in patients with AL amyloidosis. STUDY TYPE: Prospective observational study. POPULATION: 226 biopsy-proven systemic AL amyloidosis patients (age 58.62 ± 10.10 years, 135 males) and 43 healthy controls (age 42 ± 16.2 years, 20 males). FIELD STRENGTH/SEQUENCE: SSFP cine and phase sensitive inversion recovery late gadolinium enhancement (LGE) sequences, and multislice first-pass myocardial perfusion imaging with a saturation recovery turbo fast low-angle shot (SR-TurboFLASH) pulse sequence at 3.0T. ASSESSMENT: PTT was measured as the time interval between the peaks of right and left ventricular cavity arterial input function curves on first-pass perfusion MR images. STATISTICAL TESTS: Independent-sample t test, Mann-Whitney U test, Chi-square test, Fisher's exact test, analysis of variance, or Kruskal-Wallis test, as appropriate; univariable and multivariable Cox proportional hazards models and Kaplan-Meier curves, area under receiver operating characteristic curve were used to determine statistical significance. RESULTS: PTT could differentiate AL amyloidosis patients with (N = 188) and without (N = 38) cardiac involvement (area under the curve [AUC] = 0.839). During a median follow-up of 35 months, 160 patients (70.8%) demonstrated all-cause mortality. After adjustments for clinical (Hazard ratio [HR] 1.061, confidence interval [CI]: 1.021-1.102), biochemical (HR 1.055, CI: 1.014-1.097), cardiac MRI-derived (HR 1.077, CI: 1.034-1.123), and therapeutic (HR 1.063, CI: 1.024-1.103) factors, PTT predicted mortality independently in patients with AL amyloidosis. Finally, PTT could identify worse outcomes in patients demonstrating New York Heart Association class III, Mayo 2004 stage III, and transmural LGE pattern. DATA CONCLUSION: PTT may serve as a new imaging predictor of cardiac involvement and prognosis in AL amyloidosis. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.
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BACKGROUND: The clinical application of coronary MR angiography (MRA) remains limited due to its long acquisition time and often unsatisfactory image quality. A compressed sensing artificial intelligence (CSAI) framework was recently introduced to overcome these limitations, but its feasibility in coronary MRA is unknown. PURPOSE: To evaluate the diagnostic performance of noncontrast-enhanced coronary MRA with CSAI in patients with suspected coronary artery disease (CAD). STUDY TYPE: Prospective observational study. POPULATION: A total of 64 consecutive patients (mean age ± standard deviation [SD]: 59 ± 10 years, 48.4% females) with suspected CAD. FIELD STRENGTH/SEQUENCE: A 3.0-T, balanced steady-state free precession sequence. ASSESSMENT: Three observers evaluated the image quality for 15 coronary segments of the right and left coronary arteries using a 5-point scoring system (1 = not visible; 5 = excellent). Image scores ≥3 were considered diagnostic. Furthermore, the detection of CAD with ≥50% stenosis was evaluated in comparison to reference standard coronary computed tomography angiography (CTA). Mean acquisition times for CSAI-based coronary MRA were measured. STATISTICAL TESTS: For each patient, vessel and segment, sensitivity, specificity, and diagnostic accuracy of CSAI-based coronary MRA for detecting CAD with ≥50% stenosis according to coronary CTA were calculated. Intraclass correlation coefficients (ICCs) were used to assess the interobserver agreement. RESULTS: The mean MR acquisition time ± SD was 8.1 ± 2.4 minutes. Twenty-five (39.1%) patients had CAD with ≥50% stenosis on coronary CTA and 29 (45.3%) patients on MRA. A total of 885 segments on the CTA images and 818/885 (92.4%) coronary MRA segments were diagnostic (image score ≥3). The sensitivity, specificity, and diagnostic accuracy were as follows: per patient (92.0%, 84.6%, and 87.5%), per vessel (82.9%, 93.4%, and 91.1%), and per segment (77.6%, 98.2%, and 96.6%), respectively. The ICCs for image quality and stenosis assessment were 0.76-0.99 and 0.66-1.00, respectively. DATA CONCLUSION: The image quality and diagnostic performance of coronary MRA with CSAI may show good results in comparison to coronary CTA in patients with suspected CAD. EVIDENCE LEVEL: 1. TECHNICAL EFFICACY: 2.
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Doença da Artéria Coronariana , Aprendizado Profundo , Feminino , Humanos , Masculino , Doença da Artéria Coronariana/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Constrição Patológica , Inteligência Artificial , Angiografia Coronária , Sensibilidade e EspecificidadeRESUMO
OBJECTIVES: Hypertrophic cardiomyopathy (HCM) patients are closely related to LA functional impairment. Left atrial (LA) strain provides more insight into LA function. The study aimed to investigate the left atrial dysfunction of HCM patients by rapid semi-automatic method and determine the predictive value of left atrial long-axis strain (LAS) for atrial fibrillation (AF). METHODS: We enrolled 372 HCM patients and 100 healthy participants to assess the LA functional parameters. LAS was obtained by semi-automated tracking of the distance between the mid-posterior point of LA wall which is defined as the intersection of the LA long axis and the posterior wall, and the origins of the mitral valve. The inferior and anterior mitral valve annular insertion points on the 2-chamber view and the lateral and septal insertion points on the 4-chamber view were chosen as the origins of the mitral valve. The clinical outcome was defined as detecting the onset of AF. RESULTS: The LA strain values were analyzed as 20.8 ± 7.48% for εs, 9.81 ± 5.09% for εe, and 10.91 ± 4.24% for εa in HCM patients, which decreased significantly compared with normal controls. Significant correlations were detected between LV functional parameters and LA strain. During a median follow-up of 61 months, 44 (11.8%) patients developed AF. In the Cox regression analysis, LA strain was identified as a significant predictor of the onset of AF. CONCLUSIONS: HCM patients had impairment of LA strain before LA enlargement and reduced EF. LA-LAS can be used as a predictive value for predicting the occurrence of AF in HCM patients. KEY POINTS: ⢠Fast semi-automated long-axis strain analysis by CMR is feasible and effective for evaluating the LA longitudinal function. ⢠Hypertrophic cardiomyopathy patients show significant impairment of left atrial strain before LA enlargement. ⢠The left atrial long-axis strain was an independent predictor of atrial fibrillation in hypertrophic cardiomyopathy.
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Apêndice Atrial , Fibrilação Atrial , Cardiomiopatia Hipertrófica , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico por imagem , Átrios do Coração/diagnóstico por imagem , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Função do Átrio EsquerdoRESUMO
OBJECTIVES: To examine a compressed sensing artificial intelligence (CSAI) framework to accelerate image acquisition in non-contrast-enhanced whole-heart bSSFP coronary magnetic resonance (MR) angiography. METHODS: Thirty healthy volunteers and 20 patients with suspected coronary artery disease (CAD) scheduled for coronary computed tomography angiography (CCTA) were enrolled. Non-contrast-enhanced coronary MR angiography was performed with CSAI, compressed sensing (CS), and sensitivity encoding (SENSE) methods in healthy participants and with CSAI in patients. Acquisition time, subjective image quality score, and objective image quality measurement (blood pool homogeneity, signal-to-noise ratio [SNR], and contrast-to-noise ratio [CNR]) were compared among the three protocols. The diagnostic performance of CASI coronary MR angiography for predicting significant stenosis (≥ 50% diameter stenosis) on CCTA was evaluated. The Friedman test was performed to compare the three protocols. RESULTS: Acquisition time was significantly shorter in the CSAI and CS groups than in the SENSE group (10.2 ± 3.2 min vs. 10.9 ± 2.9 min vs. 13.0 ± 4.1 min, p < 0.001). However, the CSAI approach had the highest image quality scores, blood pool homogeneity, mean SNR value, and mean CNR value (all p < 0.001) compared with the CS and SENSE approaches. The sensitivity, specificity, and accuracy of CSAI coronary MR angiography per patient were 87.5% (7/8), 91.7% (11/12), and 90.0% (18/20); those per vessel were 81.8% (9/11), 93.9% (46/49), and 91.7% (55/60); and those per segment were 84.6% (11/13), 98.0% (244/249), and 97.3% (255/262), respectively. CONCLUSIONS: CSAI yielded superior image quality within a clinically feasible acquisition time in healthy participants and patients with suspected CAD. CLINICAL RELEVANCE STATEMENT: The non-invasive and radiation-free CSAI framework could be a promising tool for rapid screening and comprehensive examination of the coronary vasculature in patients with suspected CAD. KEY POINTS: ⢠This prospective study showed that CSAI enables a reduction in acquisition time by 22% with superior diagnostic image quality compared with the SENSE protocol. ⢠CSAI replaces the wavelet transform with a CNN as a sparsifying transform in the CS algorithm, achieving high coronary MR image quality with reduced noise. ⢠CSAI achieved per-patient sensitivity of 87.5% (7/8) and specificity of 91.7% (11/12) respectively for detecting significant coronary stenosis.
Assuntos
Doença da Artéria Coronariana , Aprendizado Profundo , Humanos , Angiografia Coronária/métodos , Estudos Prospectivos , Constrição Patológica , Estudos de Viabilidade , Inteligência Artificial , Doença da Artéria Coronariana/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Angiografia por Ressonância Magnética/métodosRESUMO
BACKGROUND: Although reference ranges of T1 and T2 mapping are well established for cardiovascular magnetic resonance (CMR) at 1.5T, data for 3T are still lacking. The objective of this study is to establish reference ranges of myocardial T1 and T2 based on a large multicenter cohort of healthy Chinese adults at 3T CMR. METHODS: A total of 1015 healthy Chinese adults (515 men, age range: 19-87 years) from 11 medical centers who underwent CMR using 3T Siemens scanners were prospectively enrolled. T1 mapping was performed with a motion-corrected modified Look-Locker inversion recovery sequence using a 5(3)3 scheme. T2 mapping images were acquired using T2-prepared fast low-angle shot sequence. T1 and T2 relaxation times were quantified for each slice and each myocardial segment. The T1 mapping and extracellular volume standardization (T1MES) phantom was used for quality assurance at each center prior to subject scanning. RESULTS: The phantom analysis showed strong consistency of spin echo, T1 mapping, and T2 mapping among centers. In the entire cohort, global T1 and T2 reference values were 1193 ± 34 ms and 36 ± 2.5 ms. Global T1 and T2 values were higher in females than in males (T1: 1211 ± 29 ms vs. 1176 ± 30 ms, p < 0.001; T2: 37 ± 2.3 ms vs. 35 ± 2.5 ms, p < 0.001). There were statistical differences in global T2 across age groups (p < 0.001), but not in global T1. Linear regression showed no correlation between age and global T1 or T2 values. In males, positive correlation was found between heart rate and global T1 (r = 0.479, p < 0.001). CONCLUSIONS: Using phantom-validated imaging sequences, we provide reference ranges for myocardial T1 and T2 values on 3T scanners in healthy Chinese adults, which can be applied across participating sites. Trial registration URL: http://www.chictr.org.cn/index.aspx . Unique identifier: ChiCTR1900025518. Registration name: 3T magnetic resonance myocardial quantitative imaging standardization and reference value study: a multi-center clinical study.
Assuntos
População do Leste Asiático , Coração , Masculino , Feminino , Adulto , Humanos , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Valores de Referência , Valor Preditivo dos Testes , Coração/diagnóstico por imagem , Miocárdio/patologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Reprodutibilidade dos TestesRESUMO
OBJECTIVES: Although lenticulostriate artery (LSA) territorial infarcts usually appear as single subcortical infarctions (SSIs) on imaging, they are caused by various etiological mechanisms. We aimed to investigate the correlation between LSA morphology and the location or size of infarcts. Besides, we explored whether the location or size of infarcts can predict the presence of middle cerebral artery (MCA) plaques and distinguish the different etiological mechanisms of SSI patients. METHODS: We prospectively included patients with acute SSI in the LSA territory. The MCA plaques, infarct features, including the number of infarct slices, lowest infarct layer index (LILI), volume, maximum area and diameter, and LSA morphological characteristics, including the number of stems and branches, length, distance, and tortuosity were evaluated. RESULTS: A total of 105 patients were enrolled. Both the average length and average distance of LSAs were negatively correlated with the maximum infarct area (P=0.048, P=0.028, respectively) and maximum infarct diameter (P=0.016, P=0.010, respectively) on axial examination and were positively correlated with LILI (P=0.020, P=0.003, respectively). The number of LSA branches was associated with the number of infarct slices (P=0.040) and LILI (P=0.043). Moreover, we found that when the LILI=1 or 2 and the number of infarct slices ≥3, the SSI patients were more likely to have MCA plaques (P=0.045). CONCLUSIONS: SSI patients with a LILI=1 or 2 and infarct slices of ≥3 were more likely to have MCA plaques. Our findings might provide a simple and feasible method to distinguish the different underlying mechanisms of SSIs for clinicians.
Assuntos
Infarto Cerebral , Angiografia por Ressonância Magnética , Humanos , Angiografia por Ressonância Magnética/métodos , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/etiologia , Artéria Cerebral Média/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , CausalidadeRESUMO
Increasing consumption of alternatives to animal-based food products can have significant implications for the sustainability of global food systems. We utilize consumers' food values to identify the drivers of demand for alternative meat and milk products in China, the world's largest consumer market. Using data from 3015 Chinese consumers, we find that public food values, such as environmental impacts and animal welfare, drive consumers' demand for alternative meat and milk. We estimate that approximately 35% of urban food shoppers constitute the potential market for these products. Plant-based meat alternatives to products with strong consumption dependence, such as pork, must compete on price, while alternatives to products with weak consumption dependence, like milk, are likely to earn market premiums. We estimate that modest consumption of alternative meat and milk products in these markets can improve food system sustainability by lowering China's animal production greenhouse gas emissions by 3.4% in addition to reducing animal slaughtering and potentially decreasing health risks associated with the consumption of animal-based food products.
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População do Leste Asiático , Substitutos do Leite , Humanos , Animais , Carne , Meio Ambiente , Leite , Comportamento do ConsumidorRESUMO
BACKGROUND: In the current NCCN guidelines, the prognosis and adjuvant chemotherapy of patients who underwent neoadjuvant chemoradiotherapy (nCRT) are based on pre-radiotherapy clinical TNM (cTNM) stage. However, the value of neoadjuvant pathologic TNM (ypTNM) stage is not clearly described. METHODS: This retrospective study investigated the prognosis and adjuvant chemotherapy which based on ypTNM stage compared to cTNM stage. Between 2010 and 2015, a total of 316 rectal cancer patients who underwent nCRT, followed by total mesorectal excision (TME), were included for analysis. RESULTS: Our findings revealed that cTNM stage was the only significant independent factor in the pCR group (HR = 6.917, 95% CI: 1.133-42.216, P = 0.038). In the non-pCR group, ypTNM stage was more important than cTNM stage in prognosis (HR = 2.704, 95% CI: 1.811-4.038, P < 0.001). In ypTNM III stage group, there was a statistically significant difference in prognosis between the patients with and without adjuvant chemotherapy (HR = 1.943, 95% CI: 1.015-3.722, P = 0.040), but there was no significant difference in cTNM III stage group (HR = 1.430, 95% CI: 0.728-2.806, P = 0.294). CONCLUSIONS: We concluded that ypTNM stage, rather than cTNM stage, might be a more important factor in the prognosis and adjuvant chemotherapy of patients with rectal cancer who underwent nCRT.