Background Ozone (O₃) is a major air pollutant. The existing monitoring system has uneven distribution of sites, insufficient coverage in underdeveloped areas, and low temporal resolution, making it difficult to obtain hourly data. This limits the dynamic identification of pollution and the formulation of prevention and control strategies. Objective To construct an hourly O₃ concentration estimation model based on ensemble machine learning, aiming to improve the accuracy of pollution exposure assessment and explore O₃ health impacts. Methods This study integrated land use regression modeling with modern machine learning techniques, employing random forest and XGBoost algorithms to construct base models, and stacking integration using non-negative least squares. The ensemble model was trained and validated across China using high-resolution, multi-source geographic data (e.g., meteorologicaldata, population density, land cover types, and aerosol optical thickness). It was tested in Taiyuan City, combined with a distributed lag non-linear model to analyze the association between O₃ and emergency admissions. Results The constructed ensemble model performed well in predicting O₃ concentration, with a higher coefficient of determination (R²) and a lower root-mean-square deviation (RMSE) compared to the single models. The R² improved from 0.90 to 0.92, and the RMSE decreased from 11.41 to 10.62, enhancing both prediction accuracy and generalization ability. In the application to Taiyuan City, the model successfully imputed the hourly-level data for the entire year. The distributed lag non-linear model analysis revealed that the relative risk (RR) values for the 6th to 8th days following O₃ exposure were 1.14 (95%CI: 1.01, 1.29), 1.16 (95%CI: 1.02, 1.31), and 1.14 (95%CI: 1.01, 1.29), respectively, which were significantly higher than 1, indicating a significant lagged association (lagged 6-8 d) between O₃ and the number of emergency room visits. Conclusion A high-precision, hourly-level O₃ concentration estimation model is successfully constructed by combining the land use regression model with an ensemble machine learning approach to provide a scientific basis for environmental policy formulation and public health intervention. The application of the model verifies its generalization ability and practical application value, which can provide a new technical framework for subsequent environmental health research.

Objective:To explore the association between sublingual microcirculatory perfusion vessel proportion (PPV), high mobility group protein B1 (HMGB1), and sepsis-induced coagulopathy (SIC), and to identify early predictive markers for clinical intervention.Methods:A total of 66 septic patients admitted to the Respiratory Intensive Care Unit (RICU) between November 2021 and May 2024 were enrolled. Based on SIC diagnosis within 24 hours of admission, patients were categorized into SIC ( n=36) and non-SIC ( n=30) groups. Clinical parameters, including prothrombin time (PT), activated partial thromboplastin time (APTT), sublingual PPV, and serum HMGB1 levels (measured at 0 h and 6 h), were analyzed. Logistic regression and receiver operating characteristic (ROC) curve analyses were performed to identify independent predictors. Results:Compared with the non-SIC group, the SIC group demonstrated significantly prolonged PT ( P<0.05) and APTT ( P<0.05), elevated 0 h lactate levels, and increased 6 h HMGB1. Spearman analysis revealed a positive correlation between 6 h PPV and platelet count ( P<0.05), while an inverse correlation was observed with 6 h PT ( P<0.05). Multivariate regression identified APTT, 6 h PPV, and 6 h HMGB1 as independent predictors of SIC. ROC analysis yielded AUC values of 0.732 for APTT, 0.802 for 6 h PPV, and 0.765 for 6 h HMGB1. The combination of 6 h PPV and HMGB1 further improved predictive accuracy (AUC=0.873). Conclusions:Prolonged APTT, decreased 6 h PPV, and elevated 6h HMGB1 are key indicators of SIC. Integrated assessment of these markers enhances early risk stratification in septic patients, facilitating timely clinical intervention.

BACKGROUND: The role of inflammation in the development of gestational diabetes mellitus (GDM) has recently become a focus of research. The systemic immune-inflammation index (SII) and systemic inflammation response index (SIRI), novel indices, reflect the body's chronic immune-inflammatory state. This study aimed to investigate the associations between the SII or SIRI and GDM. METHODS: A prospective birth cohort study was conducted at Beijing Obstetrics and Gynecology Hospital from February 2018 to December 2020, recruiting participants in their first trimester of pregnancy. Baseline SII and SIRI values were derived from routine clinical blood results, calculated as follows: SII = neutrophil (Neut) count × platelet (PLT) count/lymphocyte (Lymph) count, SIRI = Neut count × monocyte (Mono) count/Lymph count, with participants being grouped by quartiles of their SII or SIRI values. Participants were followed up for GDM with a 75-g, 2-h oral glucose tolerance test (OGTT) at 24-28 weeks of gestation using the glucose thresholds of the International Association of Diabetes and Pregnancy Study Groups (IADPSG). Logistic regression was used to analyze the odds ratios (ORs) (95% confidence intervals [CIs]) for the the associations between SII, SIRI, and the risk of GDM. RESULTS: Among the 28,124 women included in the study, the average age was 31.8 ± 3.8 years, and 15.76% (4432/28,124) developed GDM. Higher SII and SIRI quartiles were correlated with increased GDM rates, with rates ranging from 12.26% (862/7031) in the lowest quartile to 20.10% (1413/7031) in the highest quartile for the SII ( Ptrend <0.001) and 11.92-19.31% for the SIRI ( Ptrend <0.001). The ORs (95% CIs) of the second, third, and fourth SII quartiles were 1.09 (0.98-1.21), 1.21 (1.09-1.34), and 1.39 (1.26-1.54), respectively. The SIRI findings paralleled the SII outcomes. For the second through fourth quartiles, the ORs (95% CIs) were 1.24 (1.12-1.38), 1.41 (1.27-1.57), and 1.64 (1.48-1.82), respectively. These associations were maintained in subgroup and sensitivity analyses. CONCLUSION The SII and SIRI are potential independent risk factors contributing to the onset of GDM.
Humans ; Female ; Pregnancy ; Diabetes, Gestational/immunology* ; Prospective Studies ; Adult ; Inflammation/immunology* ; Glucose Tolerance Test ; Birth Cohort

Objective To investigate the correlation between the levels of activated protein C(APC),thromboxane B2(TXB2),and soluble B7-H3(sB7-H3)in the peripheral blood of elderly patients with pneumonia and the severity as well as prognosis of the disease.Methods One hundred elderly pneumonia patients admitted to our hospital from March 2022 to June 2024 were enrolled as the study group,and 100 healthy volunteers during the same period were selected as the control group.The levels of APC,TXB2,and sB7-H3 in peripheral blood were com-pared between the two groups.Study group patients were further categorized into low-risk,medium-risk,and high-risk subgroups based on the CURB-65 score(Confusion,Uremia,Respiratory rate,Blood pressure,Age≥65 years).The levels of APC,TXB2,and sB7-H3 in peripheral blood were compared among patients with varying disease severities.Pearson correlation analysis was performed to evaluate the correlation between the levels of APC,TXB2,and sB7-H3 in peripheral blood and disease severity.The study group was followed up for 30 days and subsequently divided into good prognosis and poor prognosis subgroups according to their clinical outcomes.Clinical data and peripheral blood levels of APC,TXB2,and sB7-H3 were compared between patients with different prognoses.Partial correlation analysis was conducted to assess the relationship between peripheral blood levels of APC,TXB2,and sB7-H3 and prognosis.Finally,the predictive value of these biomarkers was evaluated using the Receiver Oper-ating Characteristic(ROC)curve.Results The level of APC in the peripheral blood of the study group was signifi-cantly lower than that of the control group,whereas the levels of TXB2 and sB7-H3 were significantly higher(P<0.05).The severity of the disease in the study group was assessed using the CURB-65 score,which categorized patients into 33 mild cases,39 moderate cases,and 28 severe cases.Severe patients exhibited a lower level of APC in peripheral blood compared to moderate and mild patients.Additionally,the levels of TXB2 and sB7-H3 in moderate patients were higher than those in mild patients,while severe patients demonstrated even higher levels of TXB2 and sB7-H3 compared to both moderate and mild patients(P<0.05).Pearson correlation analysis revealed that peripheral blood APC was negatively correlated with the CURB-65 score,whereas TXB2 and sB7-H3 were positively correlated with the CURB-65 score(P<0.05).During a 30-day follow-up period,the research team identified 79 patients with good prognoses and 21 patients with poor prognoses.Significant differences were observed in diabetes prevalence,disease severity,and APACHEⅡ scores between the poor prognosis subgroup and the good prognosis subgroup(P<0.05).The levels of APC in peripheral blood were significantly lower in the poor prognosis subgroup compared to the good prognosis subgroup,whereas the levels of TXB2 and sB7-H3 were significantly higher(P<0.05).Partial correlation analysis revealed that peripheral blood APC,TXB2,and sB7-H3 were significantly associ-ated with prognosis(P<0.05).The AUC values for predicting the prognosis of elderly pneumonia patients using peripheral blood APC,TXB2,and sB7-H3 were 0.752,0.738,and 0.761,respectively,with sensitivities of 66.67%,76.19%,and 66.67%,and specificities of 78.48%,67.09%,and 78.48%.When combining these three indicators for prognostic prediction,the AUC increased to 0.918,with a sensitivity of 85.71%and a specificity of 87.34%,demonstrating a significant improvement in predictive accuracy compared to each indicator used alone(Z=2.207,2.666,2.109,P=0.027,0.008,0.035).Conclusion The levels of APC,TXB2,and sB7-H3 in the peripheral blood of elderly patients with pneumonia are significantly associated with the severity and prognosis of the disease.Combined detection of these biomarkers can serve as a reliable predictor of clinical outcomes.

Objective To investigate the correlation between the levels of activated protein C(APC),thromboxane B2(TXB2),and soluble B7-H3(sB7-H3)in the peripheral blood of elderly patients with pneumonia and the severity as well as prognosis of the disease.Methods One hundred elderly pneumonia patients admitted to our hospital from March 2022 to June 2024 were enrolled as the study group,and 100 healthy volunteers during the same period were selected as the control group.The levels of APC,TXB2,and sB7-H3 in peripheral blood were com-pared between the two groups.Study group patients were further categorized into low-risk,medium-risk,and high-risk subgroups based on the CURB-65 score(Confusion,Uremia,Respiratory rate,Blood pressure,Age≥65 years).The levels of APC,TXB2,and sB7-H3 in peripheral blood were compared among patients with varying disease severities.Pearson correlation analysis was performed to evaluate the correlation between the levels of APC,TXB2,and sB7-H3 in peripheral blood and disease severity.The study group was followed up for 30 days and subsequently divided into good prognosis and poor prognosis subgroups according to their clinical outcomes.Clinical data and peripheral blood levels of APC,TXB2,and sB7-H3 were compared between patients with different prognoses.Partial correlation analysis was conducted to assess the relationship between peripheral blood levels of APC,TXB2,and sB7-H3 and prognosis.Finally,the predictive value of these biomarkers was evaluated using the Receiver Oper-ating Characteristic(ROC)curve.Results The level of APC in the peripheral blood of the study group was signifi-cantly lower than that of the control group,whereas the levels of TXB2 and sB7-H3 were significantly higher(P<0.05).The severity of the disease in the study group was assessed using the CURB-65 score,which categorized patients into 33 mild cases,39 moderate cases,and 28 severe cases.Severe patients exhibited a lower level of APC in peripheral blood compared to moderate and mild patients.Additionally,the levels of TXB2 and sB7-H3 in moderate patients were higher than those in mild patients,while severe patients demonstrated even higher levels of TXB2 and sB7-H3 compared to both moderate and mild patients(P<0.05).Pearson correlation analysis revealed that peripheral blood APC was negatively correlated with the CURB-65 score,whereas TXB2 and sB7-H3 were positively correlated with the CURB-65 score(P<0.05).During a 30-day follow-up period,the research team identified 79 patients with good prognoses and 21 patients with poor prognoses.Significant differences were observed in diabetes prevalence,disease severity,and APACHEⅡ scores between the poor prognosis subgroup and the good prognosis subgroup(P<0.05).The levels of APC in peripheral blood were significantly lower in the poor prognosis subgroup compared to the good prognosis subgroup,whereas the levels of TXB2 and sB7-H3 were significantly higher(P<0.05).Partial correlation analysis revealed that peripheral blood APC,TXB2,and sB7-H3 were significantly associ-ated with prognosis(P<0.05).The AUC values for predicting the prognosis of elderly pneumonia patients using peripheral blood APC,TXB2,and sB7-H3 were 0.752,0.738,and 0.761,respectively,with sensitivities of 66.67%,76.19%,and 66.67%,and specificities of 78.48%,67.09%,and 78.48%.When combining these three indicators for prognostic prediction,the AUC increased to 0.918,with a sensitivity of 85.71%and a specificity of 87.34%,demonstrating a significant improvement in predictive accuracy compared to each indicator used alone(Z=2.207,2.666,2.109,P=0.027,0.008,0.035).Conclusion The levels of APC,TXB2,and sB7-H3 in the peripheral blood of elderly patients with pneumonia are significantly associated with the severity and prognosis of the disease.Combined detection of these biomarkers can serve as a reliable predictor of clinical outcomes.

OBJECTIVE To provide a reference for the selection of anti-infection schemes and pharmaceutical monitoring of pulmonary infection due to Alternaria alternata after renal transplantation.METHODS The clinical pharmacist was involved in the anti-infective treatment of a patient with pulmonary infection caused by A.alternata after renal transplantation.After considering the patient's clinical symptoms,laboratory test results,and pertinent literature,clinical pharmacists determined that the patient may have developed pulmonary infection as a result of respiratory allergy due to A.alternata.The potential for infections from both Legionella and adenovirus remained a possibility.Oral administration of Voriconazole tablets was recommended for fungal therapy,while Moxifloxacin tablets were suggested for treating Legionella.Additionally,it was advised to lower the dosage of tacrolimus and stop using ganciclovir.The pharmacists meticulously tracked the patient's voriconazole trough levels and any adverse effects that might arise during the therapy.RESULTS The physician endorsed the clinical pharmacist's recommendations,and the patient's status was steady,permitting discharge.CONCLUSIONS A.alternata is a potential pathogen for immunosuppressed patients,particularly when they also experience respiratory allergic reactions.Voriconazole can serve as the first-line treatment for anti-infection therapy.Clinical pharmacists ensure the patient medication safety by adjusting the dosage of voriconazole,extending the treatment course,monitoring liver and visual functions,and being vigilant about the interaction between voriconazole and immunosuppressants.

Objective To investigate the changes in serum HP and ADMA levels in patients with ACI and the correlation of their levels with recanalization after venous thrombolysis and poor prognosis.Methods A total of 260 ACI patients undergoing venous thrombolysis in our hospital from January 2020 to March 2023 were retrospectively recruited,and were categorized into reper-fusion group(n=196)and non-reperfusion group(n=64)based on the efficacy of thrombolysis.After a 90-day follow-up,they were further divided into good prognosis group(n=159)and poor prognosis group(n=101)according to the results of a modified Rankin scale.Serum levels of HP and ADMA at admission were compared between the two groups.Logistic regression analysis was used to analyze the risk factors for non-reperfusion and poor prognosis in ACI patients.ROC curve analysis was performed to evaluate the predictive value of serum HP and ADMA levels for non-reperfusion and the diagnostic efficiency for poor prognosis in ACI patients.Results The non-reperfusion group exhibited notably elevated serum HP and ADMA levels than the reperfusion group(2.10±0.21 g/Lvs1.29±0.31 g/L,1.68±0.19 μmol/L vs 0.69±0.11 μmol/L,P＜0.01).HP and ADMA were identified as significant risk factors for uncanalization after treatment(P＜0.01).The AUC value of their combination in diagnosing uncanalization after venous thrombolys-is was 0.869(95％CI:0.830-0.908).Furthermore,significantly higher serum levels of HP and ADMA were observed in the poor prognosis group than the good prognosis group(2.27±0.19 g/L vs 1.15±0.34 g/L,1.72±0.21 μmol/L vs 0.64±0.10 μmol/L,P＜0.01).HP and ADMA were also recognized as influencing factors for poor prognosis in 90 d after treatment(P＜0.01).The AUC value was 0.816(95％CI:0.768-0.865)when their combination was used to predict poor prognosis in 90 d after treatment.Conclusion HP and ADMA are highly expressed in the se-rum of ACI patients with failed venous thrombolysis and poor prognosis.Their combined detec-tion can effectively predict both uncanalization and poor prognosis.

Objective To investigate the predictive value of lactate/albumin ratio(LAR),interleukin-6(IL-6)and CD4+T lymphocyte count in 28-day mortality in patients with severe pneumonia and sepsis.Methods A total of 73 patients with severe pneumonia and sepsis admitted to the Respiratory Intensive Care Unit(RICU)of Zhengzhou Central Hospital Affiliated to Zhengzhou University from January 2022 to June 2023 were enrolled and divided into the survival group(n=43)and the death group(n=30)according to their 28-day outcomes.The clinical data of the patients were collected from their electronic medical records,including age,gender,comorbidities with hypertension,diabetes,and coronary artery heart disease(CHD),as well as sequential organ failure assessment(SOFA)score,acute physiology and chronic health evaluation Ⅱ(APACHE Ⅱ)score,mean arterial pressure(MAP),confusion,uremia,respiratory rate,blood pressure,age ≥65 years(CURB-65)score,total bilirubin(Tbil),serum creatinine(Scr),platelet count(PLT),white blood cell(WBC)count,procalcitonin(PCT),and C-reactive protein(CRP)at admission to RICU.On the 1st,3rd,and 7th day after admission to RICU,the patients'arterial blood was drawn,and the lactate level was detected by a fully automated blood gas analyzer.The peripheral venous blood was drawn,and the serum albumin and IL-6 levels were detected by enzyme-linked immunosorbent assay,and the CD4+T lymphocyte subset count was measured by flow cytometry.The LAR of patients on the 1st,3rd and 7th day was calculated.The clinical data of the patients and the LAR,IL-6 level and CD4+T lymphocyte count on the 1st,3rd,and 7th day were compared between the two groups.The influencing factors of 28-day mortality in patients with severe pneumonia and sepsis were analyzed by logistic regression,and the predictive value of each influencing factor on the 28-day mortality in patients with severe pneumonia and sepsis was evaluated by the receiver operating characteristic(ROC)curve.Results There was no significant difference in gender,age,proportions of comorbidities with hypertension,diabetes and CHD,length of stay in RICU,and Tbil,MAP,PLT,Scr,WBC,PCT and CRP at admission to RICU(P＞0.05).The APACHE Ⅱ and CURB-65 scores of the patients in the death group were significantly higher than those in the survival group(P＜0.05).On the 1st,3rd and 7th day,the CD4+T lymphocyte count in the death group was significantly lower than that in the survival group,while the SOFA score was significantly higher than that in the survival group(P＜0.05).On the first day,there was no significant difference in the LAR and IL-6 level be-tween the death group and the survival group(P＞0.05).However,on the 3rd and 7th day,the LAR and IL-6 level in the death group were significantly higher than those in the survival group(P＜0.05).The LAR,IL-6 level and SOFA score on the 3rd and 7th day in the survival group were significantly lower than those on the 1st day,and these indicators on the 7th day were sig-nificantly lower than those on the 3rd day(P＜0.05);the CD4+T lymphocyte count on the 3rd and 7th day was significantly higher than that on the 1st day(P＜0.05),while it showed no significant difference on the 7th and 3r day(P＞0.05).The IL-6 level on the 7th day in the death group was significantly lower than that on the 1st and 3rd day(P＜0.05),while there was no significant difference in IL-6 level on the 1st day compared with the 3r day(P＞0.05);moreover,there was no significant difference in LAR,CD4+T lymphocyte count and SOFA score between each time point(P＞0.05).Pearson correlation analy-sis showed that on the 3rd day,the LAR and IL-6 level were significantly positively correlated with the SOFA score in patients with severe pneumonia and sepsis(r=0.385,0.394;P＜0.05).On the 7th day,the LAR and IL-6 level were also significantly positively correlated with the SOFA score(r=0.418,0.402;P＜0.05).On the 3 rd and 7 th day,CD4+T lymphocyte count was significantly negatively correlated with the SOFA score(r=-0.451,-0.454;P＜0.05).Logistic regression analysis showed that the APACHE Ⅱ score,LAR,IL-6 level and CD4+T lymphocyte count on the 3rd day,and the IL-6 level and CD4+T lym-phocyte count on the 7th day were the influencing factors for 28-day mortality in patients with severe pneumonia and sepsis(P＜0.05).The ROC curve showed that the APACHE Ⅱ score,LAR,IL-6 level and CD4+T lymphocyte count on the 3rd day and the combination of the three,IL-6 level and CD4+T lymphocyte count on the 7th day and the combination of the two had certain predictive value for the 28-day mortality in patients with severe pneumonia and sepsis(P＜0.05).The area under the ROC curve(AUC)of LAR,IL-6 level and CD4+T lymphocyte count on the 3rd day combined to predict 28-day mortality in patients with severe pneumonia and sepsis was 0.891,and the AUC of APACHE Ⅱ score for predicting 28-day mortality in pa-tients with severe pneumonia and sepsis was 0.769.The AUC values of LAR,IL-6 level and CD4+T lymphocyte count on the 3rd day for predicting 28-day mortality in patients with severe pneumonia and sepsis were 0.795,0.757 and 0.770,respective-ly,and the AUC values of IL-6 level and CD4+T lymphocyte count on the 7th day and their combination for predicting 28-day mortality in patients with severe pneumonia and sepsis were 0.743,0.802 and 0.888,respectively.Conclusion The 3-day LAR,IL-6 level and CD4+T lymphocyte count,and the 7-day IL-6 level and CD4+T lymphocyte count after admission are re-lated to the 28-day mortality in patients with severe pneumonia and sepsis.The combined LAR,IL-6 level and CD4+T lympho-cyte count on the 3rd day can better assess the severity and prognosis of patients.

Objective:To explore the effect and mechanism of recovery experience, distress disclosure and self-efficacy on negative emotion in operating room nurses.Methods:The 270 operating room nurses from 4 general hospitals were selected as the research objects by convenience sampling method in May 2023, and cross-sectional investigation was carried out with general data questionnaire, Recovery Experience Scale, Depression-Anxiety-Stress Scale, Distress Disclosure Index Scale and General Self-Efficacy Scale. Model 6 of Hayes′ SPSS-Process program was used to test the mediation effect.Results:Among 270 nurses in the operating room, there were 48 males and 222 females, aged (32.07 ± 5.27) years old. The scores of recovery experience, negative emotion, distress disclosure and self-efficacy of operating room nurses were (42.36 ± 9.67), (25.37 ± 11.25), (38.13 ± 9.41) and (24.37 ± 4.57) points, respectively. The scores of recovery experience of operating rooms nurses with different ages, professional titles, working years in operating rooms and positions were statistically different ( F values were 3.04 to 10.44, all P<0.05). Recovery experience had a direct negative predictive effect on negative emotion ( β=-0.268, P<0.01), and the direct effect was 46.69%. Distress disclosure and self-efficacy had partial mediating effects between recovery experience and negative emotion, independent mediating effects were 16.38%, 30.31%, and chain mediating effects were 6.62%, respectively. Mastering experience and controlling experience were the influencing factors of depression and anxiety, and the differences were statistically significant ( t values were -3.71 to-2.11, all P<0.05). Relaxation experience and psychological detachment were the influencing factors of stress, and the differences were statistically significant ( t=-2.52, -2.30, both P<0.05). Distress disclosure and self-efficacy were the factors influencing the three dimensions of negative emotion, and the differences were statistically significant ( t values were -3.34 to -2.13, all P<0.05). Conclusions:The recovery experience of operating room nurses is a positive psychological factor affecting negative emotion, and distress disclosure and self-efficacy are important psychological mechanisms between them. Managers should pay attention to nurses' negative emotion and the mediating effect of nurses′ distress disclosure and self-efficacy, and take more active measures to reduce the level of negative emotion.

Objective:To investigate the agreement of ultrasound derived fat fraction (UDFF) with magnetic resonance imaging proton density fat fraction (MRI PDFF) on evaluating hepatic steatosis, and the performance of UDFF on diagnosing metabolic dysfunction associated steatotic liver disease (MASLD).Methods:One hundred and twenty-five volunteers and one hundred and seven inpatients who underwent abdominal ultrasound examination in Zhongda Hospital Southeast University from November 2023 to February 2024 were prospectively enrolled.UDFF and MRI PDFF were applied to evaluate hepatic steatosis. Spearman correlation test and Bland-Altman plot were applied to analyze the agreement of UDFF and MRI PDFF. Receiver operating characteristic curve (ROC) was applied to calculate the performance of UDFF on diagnosing MASLD.Results:In our participants, compared to individuals without hepatic steatosis, patients with MASLD had higher body mass index (BMI), waist-to-hip ratio, prevalence of diabetes mellitus, levels of alanine transaminase (ALT), aspertate aminotransferase (AST), alkaline phosphatase (ALP), γ-glutamyl transpeptidase (GGT), triglyceride, and UDFF (all P<0.05). The percentage of hepatic steatosis measured by UDFF and MRI PDFF was strongly correlated[ρ=0.873(95% CI=0.837-0.901), P<0.001]. UDFF performed excellent for diagnosing MASLD with an area under the curve (AUC) of 0.983(95% CI=0.956-0.995, P<0.001), and was better than semi-quantitative assessment based on two-dimensional ultrasound as well as ultrasound attenuation parameter. The optimal cut off value of UDFF to diagnose MASLD was ≥6%. Conclusions:The percentage of hepatic steatosis measured by UDFF and MRI PDFF agrees with each other, and UDFF obtains an excellent performance on diagnosing MASLD, so that UDFF should be considered a reliable imaging technique for quantitively evaluating hepatic steatosis and diagnosing MASLD.