A Novel Score Based on Controlled Attenuation Parameter Accurately Predicts Hepatic Steatosis in Individuals With Metabolic Dysfunction Associated Steatotic Liver Disease: A Derivation and Independent Validation Study.

INTRODUCTION: In metabolic dysfunction-associated steatotic liver disease, the diagnostic efficacy of controlled attenuation parameter (CAP) was not very accurate in evaluating liver fat content. The aim of this study was to develop a score, based on CAP and conventional clinical parameters, to improve the diagnostic performance of CAP regarding liver fat content. METHODS: A total of 373 participants from 2 independent Chinese cohorts were included and divided into derivation (n = 191), internal validation (n = 75), and external validation (n = 107) cohorts. Based on the significant difference index between the 2 groups defined by the magnetic resonance imaging-proton density fat fraction (MRI-PDFF) in derivation cohort, the optimal model (CAP-BMI-AST score [CBST]) was screened by the number of parameters and the area under the receiver operating characteristic curve (AUROC). In the internal and external validation cohorts, the AUROC and corresponding 95% confidence intervals (CIs) were used to compare the diagnostic performance of CBST with that of CAP. RESULTS: We constructed the CBST = -14.27962 + 0.05431 × CAP - 0.14266 × body mass index + 0.01715 × aspartate aminotransferase. When MRI-PDFF was ≥20%, ≥10%, and ≥5%, the AUROC for CBST was 0.77 (95% CI 0.70-0.83), 0.89 (95% CI 0.83-0.94), and 0.93 (95% CI 0.88-0.98), which was higher than that for CAP respectively. In the internal validation cohort, the AUROC for CBST was 0.80 (95% CI 0.70-0.90), 0.95 (95% CI 0.91-1.00), and 0.98 (95% CI 0.94-1.00). The optimal thresholds of CBST were -0.5345, -1.7404, and -1.9959 for detecting MRI-PDFF ≥20%, ≥10%, and ≥5%, respectively. DISCUSSION: The CBST score can accurately evaluate liver steatosis and is superior to the CAP.

Relationship between controlled attenuated parameter and magnetic resonance imaging-proton density fat fraction for evaluating hepatic steatosis in patients with NAFLD.

We used cross-sectional and longitudinal studies to comprehensively compare hepatic steatosis measurements obtained with magnetic resonance imaging-proton density fat fraction (MRI-PDFF) and controlled attenuated parameter (CAP) in hepatic steatosis in adults with nonalcoholic fatty liver disease (NAFLD). A total of 185 participants with NAFLD and 12 non-NAFLD controls were recruited. CAP and MRI-PDFF data were collected at baseline from all participants and from 95 patients included in the longitudinal study after 24 weeks of drug or placebo intervention. Pearson correlation, linear regression, and piecewise linear regression analyses were used to evaluate the relationship between the two modalities. Linear analysis suggested a positive correlation between CAP and MRI-PDFF (r = 0.577, p < 0.0001); however, piecewise linear regression showed no correlation when CAP was ≥331 dB/m (p = 0.535). In the longitudinal study, both the absolute and relative change measurements were correlated between the two modalities; however, the correlation was stronger for the relative change (relative r = 0.598, absolute r = 0.492; p < 0.0001). Piecewise linear regression analysis revealed no correlation when CAP was reduced by more than 53 dB/m (p = 0.193). Conclusions: We found a correlation between CAP and MRI-PDFF measurements for grading hepatic steatosis when CAP was <331 dB/m. While the measured absolute change and relative change were correlated, it was stronger for the relative change. These findings have implications for the clinical utility of CAP or MRI-PDFF in the clinical diagnosis and assessment of NAFLD.

Molecular structure, dynamics, and mechanical behavior of sodium aluminosilicate hydrate (NASH) gel at elevated temperature: a molecular dynamics study.

Sodium aluminosilicate hydrate (NASH) gel is the primary adhesive constituent in environmentally friendly geopolymer. In this study, to understand the thermal behavior of the material, molecular dynamics was utilized to investigate the molecular structure, dynamic property, and mechanical behavior of NASH gel subjected to temperature elevation from 300 K to 1500 K. The aluminosilicate skeleton in NASH gel provides plenty of oxygen sites to accept H-bond from the invading water molecules. Upon heating, around 18.2% of water molecules are decomposed and produce silicate and aluminate hydroxyls. About 87% of hydroxyls are associated with the aluminate skeleton, which weakens the Al-O bonds and disturbs the O-Al-O angle and the local structure, transforming it from an aluminate tetrahedron to a pentahedron and octahedron. With increasing temperature, both Al-O-Si and Si-O-Si bonds are stretched to be broken and the network structure of the NASH gel is gradually transformed into a branch and chain structure. Furthermore, the self-diffusivity of water molecules and sodium dramatically increases with the elevation of temperature, because the decrease in connectivity of the aluminosilicate network reduces the chemical and geometric restriction on the water and ions in NASH gel under higher temperatures. The high temperature also contributes to around 63% of the water molecules further dissociating and hydroxyl groups forming; meanwhile proton exchange between the water molecules and aluminosilicate network frequently takes place. In addition, a uniaxial tensile test was utilized to study the mechanical behavior of the NASH gel at different temperatures. During the tensile test, the aluminosilicate network was found to depolymerize into a branch or chain structure which plays a critical role in resisting the tensile loading. In this process, the breakage of the aluminosilicate skeleton is accompanied with hydrolytic reactions that further deteriorate the structure. Due to the reduction of the chemical bond stability at elevated temperature, both the tensile strength and stiffness of the NASH gel are weakened significantly. However, the ductility of the NASH gel is improved because of the higher extent of structural arrangement at the yield stage and partly due to the lower water attack. Hopefully, the present study can provide valuable molecular insights on the design of alkali-activated materials with high sustainability and durability.