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Diagnostic accuracy of noninvasive steatosis biomarkers with magnetic resonance imaging proton density fat fraction as gold standard
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作者 Jia-Liang Chen Shao-Jie Duan +1 位作者 Sheng Xie Shu-Kun Yao 《World Journal of Radiology》 2025年第5期45-57,共13页
BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is the most common chronic liver disea-se.The accuracy of noninvasive biomarkers for detecting hepatic steatosis is still limited.AIM To assess the diagnostic performa... BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is the most common chronic liver disea-se.The accuracy of noninvasive biomarkers for detecting hepatic steatosis is still limited.AIM To assess the diagnostic performance of noninvasive steatosis biomarkers in diag-nosing NAFLD using magnetic resonance imaging proton density fat fraction(MRI-PDFF)as the gold standard.METHODS A total of 131 suspected NAFLD patients(60%male,median age 36 years)under-going MRI-PDFF were consecutively recruited from a tertiary hospital.Steatosis grades determined by MRI-PDFF were classified as none(<5%),mild(5%-11%),moderate(11%-17%),and severe(≥17%).Six steatosis biomarkers were calculated according to clinical parameters and laboratory tests,including fatty liver index,hepatic steatosis index,ZJU index,Framingham steatosis index,triglycerides and glucose index,and visceral adiposity index.The accuracy of these biomarkers in detecting hepatic steatosis was evaluated using the area under the receiver operating characteristic curves(AUCs).The Youden index was used to determine the optimal cut-off for each biomarker.The linear trend analysis of each biomarker across the steatosis grades was conducted by Mantel-Haenszelχ2 test.Spearman's rank correlation assessed the relationship between steatosis biomarkers and MRI-PDFF.RESULTS Steatosis grades based on MRI-PDFF prevalence were:None 27%,mild 40%,moderate 15%and severe 18%.Six steatosis biomarkers showed a linear trend across the steatosis grades and a significant positive correlation with MRI-PDFF.The six steatosis biomarkers demonstrated AUCs near 0.90(range:0.857-0.912,all P<0.001)for diagnosing NAFLD by MRI-PDFF≥5%.The optimal cut-offs showed sensitivity between 84.4%-91.7%and specificity between 71.4%-85.7%.The diagnostic performance of these biomarkers in detecting moderate-to-severe and severe steatosis was relatively weaker.CONCLUSION These noninvasive steatosis biomarkers accurately diagnosed NAFLD and correlated well with MRI-PDFF for detecting NAFLD,but they did not effectively detect moderate or severe steatosis. 展开更多
关键词 Nonalcoholic fatty liver disease DIAGNOSIS Noninvasive biomarker Magnetic resonance imaging proton density fat fraction Chinese population
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A thermodynamic model on predicting density of medium-Mn steels with experimental verification 被引量:2
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作者 Guo-hui Shen Peng-yu Wen Hal-wen Luo 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2017年第11期1078-1084,共7页
A new model on predicting the density of hot-rolled multi-phased medium-Mn steel has been presen ted on the basis of thermodynamic calculations. This is an integrated model, which includes one for calculating the reta... A new model on predicting the density of hot-rolled multi-phased medium-Mn steel has been presen ted on the basis of thermodynamic calculations. This is an integrated model, which includes one for calculating the retained austenite (RA) fraction and the other for volume expansion during the aus tenite-to martensite transformation, because both of them are key parameters for calculating the den- sity of steel at ambient temperature. The existing empirical equations for calculating Mx temperature and lattice constants of both martensite and austenite have been all rcassessed by the XRD measure ments on the microstructures of seven hot-rolled medium-Mn steels. Finally, the densities ot seven steels were calculated merely from compositions and compared with the measured ones. The differ ence between them is no more than 1 %, suggesting that the presented model should be of good value in designing the low density steels. 展开更多
关键词 density Medium Mn steel Retained austenite fraction Volume expansion Transformation
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Reliability analysis based on a novel density estimation method for structures with correlations 被引量:2
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作者 Baoyu LI Leigang ZHANG +2 位作者 Xuejun ZHU Xiongqing YU Xiaodong MA 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第3期1021-1030,共10页
Estimating the Probability Density Function(PDF) of the performance function is a direct way for structural reliability analysis,and the failure probability can be easily obtained by integration in the failure domai... Estimating the Probability Density Function(PDF) of the performance function is a direct way for structural reliability analysis,and the failure probability can be easily obtained by integration in the failure domain.However,efficiently estimating the PDF is still an urgent problem to be solved.The existing fractional moment based maximum entropy has provided a very advanced method for the PDF estimation,whereas the main shortcoming is that it limits the application of the reliability analysis method only to structures with independent inputs.While in fact,structures with correlated inputs always exist in engineering,thus this paper improves the maximum entropy method,and applies the Unscented Transformation(UT) technique to compute the fractional moments of the performance function for structures with correlations,which is a very efficient moment estimation method for models with any inputs.The proposed method can precisely estimate the probability distributions of performance functions for structures with correlations.Besides,the number of function evaluations of the proposed method in reliability analysis,which is determined by UT,is really small.Several examples are employed to illustrate the accuracy and advantages of the proposed method. 展开更多
关键词 Fractional moment Maximum entropy Probability density function Reliability analysis Unscented transformation
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Quantitative Evaluation of Fat Composition in Lumbar Vertebral Body and Paraspinal Muscle by Proton Density Fat Fraction with MRI
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作者 Yuji Kasukawa Michio Hongo +5 位作者 Toshihito Ebina Taishi Chiba Daisuke Kudo Ryota Kimura Yoichi Shimada Naohisa Miyakoshi 《Open Journal of Orthopedics》 2022年第3期85-96,共12页
Purpose: Bone marrow and muscle adiposity have been considered to correlate with osteoporosis and Sarcopenia. Proton Density Fat Fraction (PDFF) can be measured by Magnetic Resonance Imaging (MRI). The purpose of the ... Purpose: Bone marrow and muscle adiposity have been considered to correlate with osteoporosis and Sarcopenia. Proton Density Fat Fraction (PDFF) can be measured by Magnetic Resonance Imaging (MRI). The purpose of the present study was to measure PDFF in the lumbar spine, paraspinal muscle and subcutaneous fat tissue. Methods: Participants were comprised of 30 patients (18 males, 12 females;age range, 14 - 87 years) who underwent MRI due to low back symptoms. PDFFs for the body of the fourth lumbar vertebra (L4), paraspinal muscle, and subcutaneous fat were measured. Results: PDFFs of the vertebral body and subcutaneous fat were significantly higher than that of paraspinal muscle (p < 0.001). PDFF was significantly higher for subcutaneous fat than for the vertebral body (p < 0.001). Although no significant differences in PDFF of the vertebral body, paraspinal muscle, and subcutaneous fat between females and males, PDFFs of the vertebral body and paraspinal muscle were significantly higher in older subjects (>63 years) than in younger subjects (Conclusions: PDFF of the vertebral body was significantly higher than that of paraspinal muscle. PDFFs of the vertebral body and paraspinal muscle were significantly lower in younger subjects than in older subjects. 展开更多
关键词 Proton density Fat Fraction Vertebral Body Bone Marrow Para-Spinal Muscle Age Bone Mineral density
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The enhancements of pore morphology and size distribution by straw return are mediated by increases in aggregate-associated carbon and nitrogen
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作者 Ying Zhao Xiaozeng Han +4 位作者 Chen Qiu Wenxiu Zou Xinchun Lu Jun Yan Xu Chen 《Journal of Integrative Agriculture》 2025年第4期1562-1576,共15页
The accumulation of soil organic carbon(SOC)and total nitrogen(TN)is easily accomplished by returning crop straw,which strongly affects the formation and pore structure of aggregates,especially in black soil.We return... The accumulation of soil organic carbon(SOC)and total nitrogen(TN)is easily accomplished by returning crop straw,which strongly affects the formation and pore structure of aggregates,especially in black soil.We returned maize straw at different rates(6,000,9,000,12,000 and 15,000 kg ha^(-1))for nine years to investigate its influence on the SOC and TN contents in the SOC fractions of aggregates by combining size and density fractionation.Their subsequent influences on pore morphology and size distribution characteristics were examined using X-ray microcomputed tomography scanning(μCT).The results showed that returning straw significantly increased the contents of C and N in the SOC fractions of aggregates,especially at the return rates of 12,000 and 15,000 kg ha^(-1),which in turn promoted aggregate formation and stability,and ultimately amended pore structure.The pore size>100μm,porosity(>2μm),and morphological characteristics(anisotropy,circularity,connectivity and fractal dimension)significantly increased,but the total number of pores significantly decreased(P<0.05).Our results indicated that the amendment of the pore morphology and size distribution of soil aggregates was primarily controlled by the higher contents of C and N in the density fractions of aggregates,rather than in the aggregate sizes.Furthermore,this pore network reconfiguration favored the storage of C and N simultaneously.The findings of this study offer valuable new insights into the relationships between C and N storage and the pore characteristics in soil aggregates under straw return. 展开更多
关键词 aggregate pore structure black soil density fractions water-stable aggregates X-ray micro-computed tomography
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Stability of soil organic carbon changes in successive rotations of Chinese fir(Cunninghamia lanceolata(Lamb.) Hook) plantations 被引量:7
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作者 ZHANG Jian WANG Silong +1 位作者 FENG Zongwei WANG Qingkui 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第3期352-359,共8页
The importance of soil organic carbon (SOC) under forests in the global carbon cycle depends on the stability of the soil carbon and its availability to soil microbial biomass. We investigated the effects of success... The importance of soil organic carbon (SOC) under forests in the global carbon cycle depends on the stability of the soil carbon and its availability to soil microbial biomass. We investigated the effects of successive rotations of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) plantations on the stability of SOC and its availability to microbes by adopting the two-step hydrolysis with H2SO4 and density fractionation. The results showed that successive rotations of Chinese fir decreased the quantity of total SOC, recalcitrant fraction, and carbohydrates in Labile Pool I (LPI), and microbial properties evidently, especially at 0-10 cm horizon. However, cellulose included in Labile Pool Ⅱ (LP Ⅱ) and the cellulose/total carbohydrates ratio increased in successive rotations of Chinese fir. The noncellulose of carbohydrates included in LPI maybe highly available to soil microbial biomass. Hence the availability of SOC to microbial biomass declined over the successive rotations. Although there was no significant change in recalcitrance of SOC over the successive rotations of Chinese fir, the percentage of heavy fraction to total SOC increased, suggesting that the degree of physical protection for SOC increased and SOC became more stable over the successive rotations. The degradation of SOC quality in successive rotation soils may be attributed to worse environmental conditions resulted from disturbance that related to "slash and burn" site preparation. Being highly correlated with soil microbial properties, the cellulose/total carbohydrates ratio as an effective indicator of changes in availability of SOC to microbial biomass brought by management practices in forest soils. 展开更多
关键词 Chinese fir plantation forest soils organic carbon microbial property biochemical quality density fractionation
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Solid-State 13C Nuclear Magnetic Resonance Spectroscopic Characterization of Soil Organic Matter Fractions in a Forest Ecosystem Subjected to Prescribed Burning and Thinning 被引量:1
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作者 thilini d.ranatunga zhongqi he +1 位作者 kamala n.bhat junyan zhong 《Pedosphere》 SCIE CAS CSCD 2017年第5期901-911,共11页
Forest management practices such as prescribed burning and thinning in forest ecosystems may alter the properties of soil organic matter (SOM). In this study, surface softs from field plots in the Bankhead National ... Forest management practices such as prescribed burning and thinning in forest ecosystems may alter the properties of soil organic matter (SOM). In this study, surface softs from field plots in the Bankhead National Forest, Alabama, USA, were used to investigate possible SOM transformations induced by thinning and burning. Elemental analysis and solid-state 13C cross polarization magic angle spinning nuclear magnetic resonance (13C CPMAS NMR) spectroscopy were used to characterize SOM fractions in whole soils, humic substances, and density fractions. Our data revealed that the changes in SOM fractions due to the repeated burning carried out in the forest ecosystem studied were involved mainly with alkyl C, O-alkyl C, and carbohydrate functional groups, implying that most prominent reactions that occurred involved dehydrogenation, de-oxygenation, and decarboxylation. In addition, burning and thinning might have also affected the distribution and composition of free and occluded particulate SOM fractions. The limited structural changes in SOM fractions suggested that low-intensity prescribed fire in the forest ecosystem studied will not create major structural changes in SOM fractions. 展开更多
关键词 density fractionation forest fires forest management practices forest soils fulvic acids humic acids HUMIN particulateorganic matter
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Land use type shapes carbon pathways in Tibetan alpine ecosystems:Characterization of ^(13)C abundance in aggregates and density fractions
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作者 Xin Wan Dangjun Wang +7 位作者 Junya Li Shuaiwen Zhang Linyang Li Minghui He Zhiguo Li Hao Jiang Peng Chen Yi Liu 《Journal of Integrative Agriculture》 2026年第2期448-459,共12页
Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In ... Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In this study,the effect of land use type on carbon storage and fractionation was quantified based on organic carbon and its ^(13)C abundance at the microscale of soil aggregates and density fractions in Tibetan alpine ecosystems.The sequence of soil aggregate destruction in the land use types of plantation(13.1%)<shrubland(32.7%)<grassland(47.9%)<farmland(61.8%)shows that plantations strengthen the soil structure.Plantation land had a greater contribution of light fraction organic carbon(28.3%)but a lower contribution of mineral-associated organic carbon(40.6%)to the carbon stock compared to farmland(13.5 and 70.3%).Interestingly,plantation land enhanced the aggregational differentiation of organic carbon and ^(13)C in each density fraction,whereas no such phenomenon existed in the soil organic carbon.Carbon isotope analyses revealed that carbon transfer in the plantation land occurred from the light fraction in macroaggregates(–24.9‰)to the mineral-associated fraction in microaggregates(–19.9‰).When compared to the other three land use types,the low transferability of carbon in aggregates and density fractions in plantation land provides a stable carbon pool for the Tibetan Plateau.This study shows that plantations can mitigate global climate change by slowing carbon transfer and increasing carbon storage at the microscale of aggregates and density fractions in alpine regions. 展开更多
关键词 land use type soil aggregate density fractions carbon transfer Tibetan Plateau
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Comparison of Soil Nitrogen Availability Indices under Two Temperate Forest Types
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作者 ZHONG Zhe-Ke F. MAKESCHIN 《Pedosphere》 SCIE CAS CSCD 2006年第3期273-283,共11页
To evaluate the validity of different indices in estimating soil readily mineralizable N, soil microbial biomass (Nmic), soil active N (SAN), soluble organic N (SON), net N mineralization rate (NNR) and gross ... To evaluate the validity of different indices in estimating soil readily mineralizable N, soil microbial biomass (Nmic), soil active N (SAN), soluble organic N (SON), net N mineralization rate (NNR) and gross N mineralization rate (GNR) in mineral soils (0-10 cm) from six forest stands located in central Germany were determined and compared with two sampling times: April and November. Additionally, soil density fractionation was conducted for incubated soils (with addition of ^15NH4-N and glucose, 40 days) to observe the sink of added ^15N in different soil fractions. The study showed that Nmic and NNR in most stands differed significantly (P 〈 0.05) between the two sampling times, but not GNR, SAN and SON. In November, no close relationships were found between GNR and other N indices, or between Nrnic, SON, and SAN and forest type. However, in April, GNR was significantly correlated (P 〈 0.05) with Nmic, SAN, and NNR along with Nmlc under beech being significantly higher (P 〈 0.05) than under conifers. Furthermore, density fractionation revealed that the light fraction (LF, 0.063-2 mm, 〉 1.7 gcm^-3) was not correlated with the other N indices. In contrast, results from the incubation study proved that more 15N was incorporated into the heavy fraction (HF 〈 0.063 ram, 〉 1.7 g cm^-3) than into LF, indicaing that more labile N existed in HF than in LF. These findings suggested that attention should be paid to the differences existing in N status between agricultural and forest soils. 展开更多
关键词 density fractionation forest soils N availability soil N indices
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Two-point Dixon and six-point Dixon magnetic resonance techniques in the detection,quantification and grading of hepatic steatosis 被引量:2
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作者 Mohamed Elfaal Alanna Supersad +6 位作者 Craig Ferguson Stephanie Locas Florin Manolea Mitchell P Wilson Medica Sam Wendy Tu Gavin Low 《World Journal of Radiology》 2023年第10期293-303,共11页
BACKGROUND Hepatic steatosis is a very common problem worldwide.AIM To assess the performance of two-and six-point Dixon magnetic resonance(MR)techniques in the detection,quantification and grading of hepatic steatosi... BACKGROUND Hepatic steatosis is a very common problem worldwide.AIM To assess the performance of two-and six-point Dixon magnetic resonance(MR)techniques in the detection,quantification and grading of hepatic steatosis.METHODS A single-center retrospective study was performed in 62 patients with suspected parenchymal liver disease.MR sequences included two-point Dixon,six-point Dixon,MR spectroscopy(MRS)and MR elastography.Fat fraction(FF)estimates on the Dixon techniques were compared to the MRS-proton density FF(PDFF).Statistical tests used included Pearson’s correlation and receiver operating characteristic.RESULTS FF estimates on the Dixon techniques showed excellent correlation(≥0.95)with MRS-PDFF,and excellent accuracy[area under the receiver operating characteristic(AUROC)≥0.95]in:(1)Detecting steatosis;and(2)Grading severe steatosis,(P<0.001).In iron overload,two-point Dixon was not evaluable due to confounding T2*effects.FF estimates on six-point Dixon vs MRS-PDFF showed a moderate correlation(0.82)in iron overload vs an excellent correlation(0.97)without iron overload,(P<0.03).The accuracy of six-point Dixon in grading mild steatosis improved(AUROC:0.59 to 0.99)when iron overload cases were excluded.The excellent correlation(>0.9)between the Dixon techniques vs MRSPDFF did not change in the presence of liver fibrosis(P<0.01).CONCLUSION Dixon techniques performed satisfactorily for the evaluation of hepatic steatosis but with exceptions. 展开更多
关键词 Chemical shift encoded Dixon magnetic resonance techniques Hepatic steatosis Liver fat quantification Magnetic resonance spectroscopy Proton density fat fraction ULTRASOUND
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The stability of carbon from a maize-derived hydrochar as a function of fractionation and hydrothermal carbonization temperature in a Podzol 被引量:1
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作者 Megan de Jager Frank Schröter +1 位作者 Michael Wark Luise Giani 《Biochar》 SCIE 2022年第1期315-326,共12页
Hydrochar(HC)produced by the hydrothermal carbonization(HTC)of typically wet biomass is generally considered to be less effective for carbon(C)sequestration in soils compared to biochar(BC)by pyrolysis,due to a higher... Hydrochar(HC)produced by the hydrothermal carbonization(HTC)of typically wet biomass is generally considered to be less effective for carbon(C)sequestration in soils compared to biochar(BC)by pyrolysis,due to a higher content of more easily decomposable C.Although the recalcitrance of HC is suggested to improve with increasing HTC production temperature,the way it interacts and becomes associated with soil organic matter(SOM)fractions of different stabilities against decomposition,may also influence its effectiveness for C sequestration in soils.In that respect,this study aimed to verify the potential of HCs from maize silage produced at different HTC temperatures(190,210 and 230℃)for C sequestration in a HC-amended sandy loam Podzol.To do this,we conducted a pot trial experiment and traced the fate of HC-derived C(HC-C)within different SOM fractions,namely the free-and occluded particulate organic matter(POMF and POMO,respectively)fractions and that comprising organic matter(OM)bound to clays(OMCl).Approx.1 year after applying 5%of the different HTC temperature HCs to the soil,the SOM fractions were isolated by density fractionation for each HC treatment(HC190,HC210 and HC230)and the control(absent of HC).All fractions and the HCs were analyzed for organic C(OC)content and isotopic signatures(δ^(13)C).From the δ^(13)C signatures,the amount of HC-C and native soil organic carbon(SOC)within each fraction was calculated.Increased C contents and decreased H/C and O/C ratios were observed with increasing HTC production temperatures,which sug-gests a lower stability for the low temperature HC.After ca.1 year,a loss of~20-23%of the bulk soil TOC was found in the HC-amended soils.The POMF fraction of the HC-amended soils showed losses of 68-81%HC-C and 52-72%native SOC,which may be due to a positive priming effect caused by HC addition.The POM_(O) and OM_(Cl) fractions of the HC-amended soils contained more OC than the control,indicating the integration of HC-C together with SOM within these more stable fractions,while the effect of HTC production temperature on the level of decomposition of the resultant HCs was negligible.In all HC treatments,the OM_(Cl) fraction comprised the least amount of HC-C,thus showing the weakest response to C amendment.In conclusion,long(er)-term research on the C net balance that accounts for the observed priming-induced TOC losses and the HC-C enrichment in more stable fractions is required to verify the potential of the different HCs for the purpose of C sequestration in soils. 展开更多
关键词 Hydrochar Carbon sequestration Carbon stabilization Soil organic matter fractions Soil density fractionation δ^(13)C analysis
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Empagliflozin for non-diabetic metabolic dysfunction-associated steatotic liver disease:a promising therapeutic agent in transition
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作者 Mohamed El-Kassas Hongqun Liu Samuel S.Lee 《Hepatobiliary Surgery and Nutrition》 2025年第4期651-654,共4页
Metabolic dysfunction-associated steatotic liver disease(MASLD),previously known as non-alcoholic fatty liver disease(NAFLD),has emerged as a leading cause of chronic liver disease globally,reflecting the convergence ... Metabolic dysfunction-associated steatotic liver disease(MASLD),previously known as non-alcoholic fatty liver disease(NAFLD),has emerged as a leading cause of chronic liver disease globally,reflecting the convergence of rising obesity,insulin resistance,and type 2 diabetes mellitus(1).The disease burden is not only liver-related but systemic,contributing to increased cardiovascular risk,malignancy,and reduced quality of life(2).The clinical spectrum of MASLD ranges from simple steatosis to metabolic dysfunction-associated steatohepatitis(MASH),fibrosis,and cirrhosis,with a growing share of hepatocellular carcinoma cases now being attributed to MASLD rather than viral etiologies(3).MASLD pathophysiology involves a complex interplay of chronic low-grade inflammation,immune cell activation,and systemic metabolic dysfunction,implicating organs beyond the liver,including adipose tissue and spleen(2,3). 展开更多
关键词 Liver empagliflozin metabolic dysfunction-associated steatotic liver disease(MASLD) magnetic resonance imaging-proton density fat fraction(MRI-PDFF) sodium-glucose co-transporter-2(SGLT2)
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The challenge of sustaining therapeutic response in MASLD:insights from noninvasive liver assessment
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作者 Nobuharu Tamaki Masayuki Kurosaki 《Hepatobiliary Surgery and Nutrition》 2025年第5期889-891,共3页
The prevalence of cirrhosis and hepatocellular carcinoma resulting from metabolic dysfunction-associated steatotic liver disease(MASLD)is increasing,posing a significant burden on both the economy and public health(1,... The prevalence of cirrhosis and hepatocellular carcinoma resulting from metabolic dysfunction-associated steatotic liver disease(MASLD)is increasing,posing a significant burden on both the economy and public health(1,2).Although the need for effective therapeutic strategies for MASLD is growing,pharmacologic options remain limited,with resmetirom currently the only approved drug.Consequently,lifestyle modification-particularly weight reduction through diet and exercise-remains the cornerstone of MASLD management. 展开更多
关键词 Metabolic dysfunction-associated steatotic liver disease(MASLD) liver stiffness measurement magnetic resonance imaging-proton density fat fraction(MRI-PDFF)
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Detection of hepatic and pancreatic fat infiltration in type II diabetes mellitus patients with IDEAL-Quant using 3.0T MR: comparison with single-voxel proton spectroscopy 被引量:6
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作者 Ma Jing Song Zhiqiang Yan Fuhua 《Chinese Medical Journal》 SCIE CAS CSCD 2014年第20期3548-3552,共5页
Background Type II diabetes mellitus usually related to visceral and other organ (ectopic) fat. The purpose of this study was to detect hepatic and pancreatic fat infiltration in type II diabetes meUitus patients us... Background Type II diabetes mellitus usually related to visceral and other organ (ectopic) fat. The purpose of this study was to detect hepatic and pancreatic fat infiltration in type II diabetes meUitus patients using 3.0T magnetic resonance (MR) and to compare the performance of iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL-Quant) with single-voxel proton spectroscopy (HI-MRS). Methods The study protocol was approved by our Institutional Review Board. Written informed consent was obtained from each subject in this study. We prospectively performed IDEAL-Quant and single-voxel proton spectroscopy with an echo time of 35 ms on 24 type II diabetes patients and 10 healthy volunteers. The hepatic proton density fat fraction (HPDFF) and pancreatic proton density fat fraction (PPDFF) were calculated, compared, and analyzed by t-tests and Spearman's correlation. Results The HPDFF and PPDFF measured with IDEAL-Quant were significantly different between the healthy volunteers and type II diabetes patients (th=9.377, P=0.000; tp=2.813, P=0.008). The HPDFF and PPDFF measured with MRS were also significantly different between the healthy volunteers and type II diabetes patients (th=5.342, P=0.000; tp=2.63, P=0.013). The HPDFF and PPDFF measured by the two methods were in good agreement (rh=0.854, P=-0.000; rp=0.774, P=0.000). The HPDFF and PPDFF were not significantly correlated with each other (rMRs=0.203, p=0.248; rpDEAL_Quant=0.301, P=0.084). The PPDFF measured with IDEAL-Quant was associated with body mass index (t=0.377, P=0.028). Conclusion IDEAL-Quant is a nice method for hepatic and pancreatic fat detection, and it can be applied in clinical practice. 展开更多
关键词 liver PANCREAS IDEAL-Quant HI-MRS proton density fat fraction
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Simultaneous quantification of hepatic MRI-PDFF and R2* in a rabbit model with nonalcoholic fatty liver disease 被引量:2
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作者 Xiaomin Wang Xiaojing Zhang +1 位作者 Lin Ma Shengli Li 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第9期1107-1114,共8页
Quantification of hepatic fat and iron content is important for early detection and monitoring of nonalcoholic fatty liver disease(NAFLD) patients. This study evaluated quantification efficiency of hepatic proton dens... Quantification of hepatic fat and iron content is important for early detection and monitoring of nonalcoholic fatty liver disease(NAFLD) patients. This study evaluated quantification efficiency of hepatic proton density fat fraction(PDFF) by MRI using NAFLD rabbits. R2* was also measured to investigate whether it correlates with fat levels in NAFLD. NAFLD rabbit model was successfully established by high fat and cholesterol diet. Rabbits underwent MRI examination for fat and iron analyses,compared with liver histological findings. MR examinations were performed on a 3.0 T MR system using multi-echo 3 D gradient recalled echo(GRE) sequence. MRI-PDFF showed significant differences between different steatosis grades with medians of3.72%(normal), 5.43%(mild), 9.11%(moderate) and 11.17%(severe), whereas this was not observed in R2*. Close correlation between MRI-PDFF and histological steatosis was observed(r=0.78, P=0.000). Hepatic iron deposit was not found in any rabbits. There was no correlation between R2* and either liver MRI-PDFF or histological steatosis. MR measuring MRI-PDFF and R2* simultaneously provides promising quantification of steatosis and iron. Rabbit NAFLD model confirmed accuracy of MRI-PDFF for liver fat quantification. R2* measurement and relationship between fat and iron of NAFLD liver need further experimental investigation. 展开更多
关键词 nonalcoholic fatty liver disease quantification magnetic resonance imaging proton density fat fraction R2*
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Discrepancies between Nonalcoholic and Metabolic-associated Fatty Liver Disease by Multiple Steatosis Assessment 被引量:1
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作者 Congxiang Shao Junzhao Ye +6 位作者 Xin Li Yansong Lin Shiting Feng Bing Liao Wei Wang Xiaorong Gong Bihui Zhong 《Journal of Clinical and Translational Hepatology》 SCIE 2022年第6期1013-1026,共14页
Background and Aims:The redefinition of metabolic-as-sociated fatty liver disease(MAFLD)from nonalcoholic fat-ty liver disease(NAFLD)has caused a revolution in clinical practice,and the characteristics of patients wit... Background and Aims:The redefinition of metabolic-as-sociated fatty liver disease(MAFLD)from nonalcoholic fat-ty liver disease(NAFLD)has caused a revolution in clinical practice,and the characteristics of patients with steatosis but not MAFLD remain unclear.The aims were to compare the diagnosis rate of MAFLD in NAFLD using different steato-sis methods and explore the features of non-MAFLD-NAFLD and MAFLD-non-NAFLD.Methods:A cross-sectional study enrolling consecutive individuals was conducted at three medical centers in southern China from January 2015 to September 2020.Steatosis was evaluated by liver biopsy or magnetic resonance imaging-based proton density fat frac-tion(MRI-PDFF),ultrasound,controlled attenuation param-eter(CAP),and fatty liver index(FLI).Fibrosis was assessed by the NAFLD fibrosis score,transient elastography,or shear wave elastography.Results:The study enrolled 14,985 Chi-nese adults.The agreement of MAFLD and NAFLD diagnoses were 83%for FLI,95%for ultrasound,94%for both CAP and MRI-PDFF,and 95%for liver biopsy.The body mass index,blood pressure and lipid levels among non-MAFLD-NAFLD pa-tients were similar metabolic parameters(p>0.05 for all),but not the alanine aminotransferase and the proportion of pa-tients with insulin resistance,which were significantly higher in non-MAFLD-NAFLD with significant fibrosis.Conclusions:The new MAFLD definition ruled out 5-17%of NAFLD cases.NAFLD and MAFLD-NAFLD involved more severe metabolic abnormalities than MAFLD and MAFLD-non-NAFLD.Non-MAFLD-NAFLD patients with significant fibrosis had more se-vere liver injury and increased glycemic dysregulation within the normal range.Attention should be paid to its progression. 展开更多
关键词 Controlled attenuation parameter Fatty liver index Liver biopsy Metabolic-associated fatty liver disease Magnetic resonance imaging-based proton density fat fraction
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Genome-wide Studies Reveal Genetic Risk Factors for Hepatic Fat Content
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作者 Yanni Li Eline H.van den Berg +13 位作者 Alexander Kurilshikov Dasha V.Zhernakova Ranko Gacesa Shixian Hu Esteban A.Lopera-Maya Alexandra Zhernakova Lifelines Cohort Study Vincent E.de Meijer Serena Sanna Robin P.F.Dullaart Hans Blokzijl Eleonora A.M.Festen Jingyuan Fu Rinse K.Weersma 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2024年第2期57-68,共12页
Genetic susceptibility to metabolic associated fatty liver disease(MAFLD)is complex and poorly characterized.Accurate characterization of the genetic background of hepatic fat content would provide insights into disea... Genetic susceptibility to metabolic associated fatty liver disease(MAFLD)is complex and poorly characterized.Accurate characterization of the genetic background of hepatic fat content would provide insights into disease etiology and causality of risk factors.We performed genome-wide association study(GWAS)on two noninvasive definitions of hepatic fat content:magnetic resonance imaging proton density fat fraction(MRI-PDFF)in 16,050 participants and fatty liver index(FLI)in 388,701 participants from the United Kingdom(UK)Biobank(UKBB).Heritability,genetic overlap,and similarity between hepatic fat content phenotypes were analyzed,and replicated in 10,398 participants from the University Medical Center Groningen(UMCG)Genetics Lifelines Initiative(UGLI).Meta-analysis of GWASs of MRI-PDFF in UKBB revealed five statistically significant loci,including two novel genomic loci harboring CREB3L1(rs72910057-T,P=5.40E−09)and GCM1(rs1491489378-T,P=3.16E−09),respectively,as well as three previously reported loci:PNPLA3,TM6SF2,and APOE.GWAS of FLI in UKBB identified 196 genome-wide significant loci,of which 49 were replicated in UGLI,with top signals in ZPR1(P=3.35E−13)and FTO(P=2.11E−09).Statistically significant genetic correlation(rg)between MRI-PDFF(UKBB)and FLI(UGLI)GWAS results was found(rg=0.5276,P=1.45E−03).Novel MRI-PDFF genetic signals(CREB3L1 and GCM1)were replicated in the FLI GWAS.We identified two novel genes for MRI-PDFF and 49 replicable loci for FLI.Despite a difference in hepatic fat content assessment between MRI-PDFF and FLI,a substantial similar genetic architecture was found.FLI is identified as an easy and reliable approach to study hepatic fat content at the population level. 展开更多
关键词 Hepatic fat content MAFLD Genome-wide association study Fatty liver index Magnetic resonance imaging proton density fat fraction
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Shrinking fat,healing liver:unlocking the metabolic dysfunction associated steatohepatitis puzzle
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作者 Sudhakar K.Venkatesh Ilkay S.Idilman +1 位作者 Jiahui Li Meng Yin 《Hepatobiliary Surgery and Nutrition》 SCIE 2024年第1期132-135,共4页
Metabolic dysfunction associated steatohepatitis(MASH)is a silent epidemic,hiding in the shadows of obesity,and often silently advancing towards the grave complication of cirrhosis.The distinction between MASH and sim... Metabolic dysfunction associated steatohepatitis(MASH)is a silent epidemic,hiding in the shadows of obesity,and often silently advancing towards the grave complication of cirrhosis.The distinction between MASH and simple hepatic steatosis,which is under the spectrum of metabolic dysfunction-associated steatotic liver disease(MASLD),is highly desired as it provides critical information about the prognosis of the patient.Noninvasive indicators,such as fibrosis-4(FIB-4)index and nonalcoholic fatty liver disease(NAFLD)fibrosis score that includes conventional laboratory data and clinical parameters. 展开更多
关键词 Proton density fat fraction(PDFF) metabolic dysfunction associated steatohepatitis(MASH) deep subcutaneous fat
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Specific metabolic impairments indicate loss of sustained liver improvements in metabolic dysfunction-associated steatotic liver disease treatment
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作者 Ling Luo Junzhao Ye +8 位作者 Shuyu Zhuo Bo Ma Weiyi Mai Xiaopei Cao Liuqin Liang Wei Wang Shiting Feng Zhi Dong Bihui Zhong 《Hepatobiliary Surgery and Nutrition》 SCIE 2024年第4期632-649,I0025-I0035,共29页
Background:High liver fat content(LFC)induces increased risks of both hepatic and extrahepatic progression in metabolic dysfunction-associated steatotic liver disease(MASLD),while maintaining a significant decline in ... Background:High liver fat content(LFC)induces increased risks of both hepatic and extrahepatic progression in metabolic dysfunction-associated steatotic liver disease(MASLD),while maintaining a significant decline in magnetic resonance imaging-based proton density fat fraction(MRI-PDFF)(≥30%decline relative to baseline)without worsening fibrosis results in improved histological severity and prognosis.However,the factors associated with the loss of sustained responses to treatment remain unclear,and we aim to identify them.Methods:Consecutive treatment-naïve MASLD patients between January 2015 and February 2022,with follow-up until April 2023,were included in this prospective cohort study.LFC quantified by MRI-PDFF and liver stiffness measurements(LSM)determined by two-dimensional shear wave elastography(2D-SWE)were evaluated at weeks 0,24 and 48.MRI-PDFF response was defined as a≥30%relative decline in PDFF values,and LSM response was defined as a≥1 stage decline from baseline.Results:A total of 602 MASLD patients were enrolled.Of the 303 patients with a 24-week MRI-PDFF response and complete follow-up of 48 weeks,the rate of loss of MRI-PDFF response was 29.4%,and multivariable logistic regression analyses showed that 24-week insulin resistance(IR),still regular exercise and caloric restriction after 24 weeks,and the relative decline in LFC were risk factors for loss of MRI-PDFF response.Loss of LSM response at 48 weeks occurred in 15.9%of patients,and multivariable analysis confirmed 24-week serum total bile acid(TBA)levels and the relative decline in TBA from baseline as independent predictors.No significant association was found at 48 weeks between loss of MRI-PDFF response and loss of LSM response.Conclusions:MASLD patients with IR and high TBA levels are at higher risks of subsequent diminished sustained improvements of steatosis and fibrosis,respectively. 展开更多
关键词 Metabolic dysfunction-associated steatotic liver disease(MASLD) loss of response magnetic resonance imaging-based proton density fat fraction response(MRI-PDFF response) liver stiffness measurements response(LSM response)
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