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IL-22 serves a protective function in the intestinal barrier. These protective properties of IL-22 may offer a potential treatment for ulcerative colitis (UC). However, the exact mechanisms of action remain unclear. Autophagy plays an important protective role in stabilizing the intestinal barrier. We aimed to explore the role of autophagy in the IL-22-mediated-protective effects in UC. Dextran sulfate sodium (DSS) was administrated via drinking water over 7 days to induce acute UC in BALB/c mice. Treatments with IL-22 (0.25 μg/10 g bodyweight) were started by intraperitoneal injection on days 1, 3, and 5. Weight, disease activity index, histological score, and myeloperoxidase (MPO) activity were used to evaluate the severity of colitis. The expressions of occludin and autophagy-related proteins LC3BII/I were measured by western blot analysis. The lipopolysaccharide-induced HT-29 cell model was used to explore the mechanism. In vivo, IL-22 significantly alleviated DSS-induced clinical manifestations, reduced histological injury, and inhibited MPO activity. IL-22 upregulated the expression of occludin and the LC3B II/I ratio in the colon. In vitro, IL-22 significantly lowered TNF-α levels and enhanced the expression of occludin and the LC3B II/I ratio. Importantly, inhibiting autophagy in vitro by 3-Methyladenine (3-MA) attenuated the occludin protective effects of IL-22. In summary, our findings demonstrate that IL-22 ameliorates DSS-induced ulcerative colitis, which may be attributable to activating autophagy and then promoting occludin expression. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important pathogens affecting the swine industry. In this report, a novel PRRSV strain SXht2012 was isolated from Shanxi province in China. To identify genetic characteristics of SXht2012, we conducted phylogenetic and homology analyses after sequencing its complete genome. The results revealed that SXht2012 belonged to NADC30-like strain and shared 91.3% nucleotide (nt) identity with strain NADC30. Notably, sequence alignment showed that a distinctive feature in the NSP2 region, where a 131-amino acid (aa) deletion was found in the hypervariable region (HVR). Additionally, variations were also detected in the GP5 protein, specifically in the decoy peptide, T cell peptide, and a potential glycosylation site (aa 32). Furthermore, we also found that SXht2012 was likely a recombination virus originating from NADC30-like and JXA1-like strains, and three recombination breakpoints were identified in the genome at nt positions 1516, 5280 and 6851, which correspond to the NSP2, NSP3, and NSP7 regions. Overall, these findings have significant implications for understanding the genetic variation and evolutionary dynamics of PRRSV strains. [ABSTRACT FROM AUTHOR]

Background: Adalimumab monotherapy can suppress gut inflammation and induce remission in active Crohn's disease but has some limitations. Exclusive enteral nutrition (EEN) is recommended for patients with mild to moderate Crohn's disease (CD), but implementation is challenging. Aim: To evaluate the effectiveness of adalimumab combined with partial enteral nutrition (PEN) in the induction therapy for Crohn's disease. Methods: A prospective cohort study was designed and a total of 56 patients with active CD who met the criteria for enteral nutrition (EN) treatment in our hospital were selected. The baseline data of all patients were collected including age, sex and other general information. The changes in fecal calprotectin, C-reactive protein (CRP), albumin(Alb), hemoglobin (Hb), platelets (Plt), erythrocyte sedimentation rate (ESR), Crohn's disease activity index score (CDAI), simple endoscopic score (SES-CD) and body mass index (BMI) were compared between the adalimumab combined with enteral nutrition (ADA+EN) group (N = 37) the adalimumab group (ADA) (N = 19) at week 0 (W0) and treatment outcomes at week 12(W12). Additionally, the differences between the two groups before and after treatment were evaluated. Then the ADA+EN group was divided into an adalimumab combined with exclusive enteral nutrition subgroup (ADA+EEN) and an adalimumab combined with partial nutrition subgroup (ADA+PEN) according to enteral nutrition intake. The changes in fecal calprotectin, CRP, Alb, Hb, Plt, ESR and CDAI, SES-CD and BMI were compared between the ADA+EEN group and the ADA+PEN group at week 0 (W0) and treatment outcomes at week 12(W12). The differences between the two groups before and after treatment were evaluated. To evaluate the effectiveness of the two treatments on patients' quality of life, nutritional recovery and body composition, patients in the ADA+EN group were needed to complete the Inflammatory Bowel Disease Questionnaire (IBDQ), EQ-5D-5L, the EuroQol visual analogue scale (EQ-VAS) and body composition analysis.A total of 28 patients completed all questionnaires and body composition analyses at week 0 and week 12, including 10 patients in the ADA+EEN group and 18 patients in the ADA+PEN group, respectively. The differences of in IBDQ, EQ-5D-5L and body composition analysis were compared between the two groups at week 0 (W0) and treatment outcomes at week 12(W12). Additionally, the differences between the two groups before and after treatment were evaluated. Results: These investigated indexes such as calprotectin, Hb, Plt, ESR, Alb, BMI, CRP, CDAI and SES-CD scores were significantly different before and after treatment in the ADA+EN group (p < 0.01). However, fecal calprotectin, Hb, SES-CD scores and Alb in the ADA group were not statistically significantly different from W0 to W12 (p > 0.05). The fecal calprotectin and CDAI scores in the ADA+EN group were significantly lower than those in the ADA group after treatment. The differences in all factors before and after treatment between the ADA+PEN group and the ADA+EEN group were statistically significant (p < 0.05). However, there was no significant difference between the two groups at week 12 (p > 0.05). Conclusion: Adalimumab combined with EN are more effective than ADA monotherapy in terms of endoscopy and clinical remission. By comparing the investigated indicators such as calprotectin, Hb, Plt, ESR ,CRP and SES-CD scores, it was proven that adalimumab combined with partial enteral nutrition or exclusive enteral nutrition has the same remission effect in induced Crohn's disease. The combination of biological agents and partial nutrition can improve medical order compliance, psychological burden and quality of life. Therefore, adalimumab combined with partial nutrition can be used as the first-line treatment for CD induced remission. [ABSTRACT FROM AUTHOR]

In recent years, various chaotic image encryption algorithms have been proposed, but their security issues still need to be studied and reviewed. This paper implements a cryptographic security analysis on a color image encryption algorithm based on bit-level and improved one-dimensional chaotic map (CIEA-IOCM). In CIEA-IOCM, using the pseudo-random sequences generated by an improved one-dimensional chaotic map, bit-level permutation-diffusion and linear transformation are successively performed to get its cipher image from a plain image. Based on some seemingly good performance analysis results, CIEA-IOCM claimed that it can withstand various common attacks. However, after a cryptanalysis, we found that it can be completely cracked by a chosen-plaintext attack method. The most essential reason is that there are equivalent keys for both bit-level permutation and diffusion processes, and its linear transformation can be combined and simplified. Thus, we achieved a successful security attack by obtaining the equivalent keys. Moreover, the experimental results verify the effectiveness and efficiency of our method. Therefore, our research work can provide some positive and valuable references for improving the security of chaotic image encryption algorithms. [ABSTRACT FROM AUTHOR]

This paper proposes a video security transmission enhancement algorithm based on block permutation and dynamic multiplexing sequences encryption based on 4D autonomous hyperchaotic system. Firstly, we employ the block permutation encryption and diffusion confusion encryption module, which is based on dynamic multiplexing chaotic sequences, to encrypt the plaintext and obtain the ciphertext. Subsequently, the hash value of this round's ciphertext is utilized to generate the chaotic key, produced by the multiplexing sequence of this round after mathematical processing. Then, the key is used to generate the chaotic sequence to confuse the N-th of the multiplexed sequence, and the next round of multiplexed sequence is obtained. If the current round of chaotic sequence has been completely confused, the chaotic sequence is re-generated to generate a new multiplex sequence by using the key generated by the current round key and the initial key. Finally, the above steps are repeated for the encryption of each frame of the video. Compared with the traditional permutation coding algorithm, it increases the difficulty of estimation or recognition while ensuring efficiency, and effectively improves the avalanche effect of the algorithm. Through frame by frame ciphertext closed-loop feedback, it has the ability to resist known plaintext attack and selected plaintext attack. The results show that the scheme has high security and significant diffusion characteristics, and can effectively resist various common cryptographic attacks. [ABSTRACT FROM AUTHOR]

This letter responds to an article titled "Appropriateness and imaging outcomes of ultrasound, CT, and MR in the emergency department: a retrospective analysis from an urban academic center." The authors of the letter commend the study for investigating the appropriate use of imaging modalities in an academic emergency department. However, they raise concerns about the study's methods and conclusions. They argue that the retrospective nature of the study makes it difficult to assess the clinical context of patients at initial presentation, and that the study did not consider the effect of previous medical conditions on imaging decision-making. The authors suggest that more studies with proper clinical context are needed to evaluate the appropriateness of imaging in the emergency department. [Extracted from the article]

Ambient electroreduction of nitrogen (N2) is considered as a green and feasible approach for ammonia (NH3) synthesis, which urgently demands for efficient electrocatalyst. Morphology has close relationship with catalytic activity of heterogeneous catalysts. Nanoribbon is attractive nanostructure, which possesses the flexibility of one-dimensional nanomaterials, the large surface area of two-dimensional nanomaterials, and lateral size confinement effects. In this work, Cu3P nanoribbon is proposed as a highly efficient electrocatalyst for N2-to-NH3 conversion under benign conditions. When measured in N2-saturated 0.1 M HCl, such Cu3P nanoribbon achieves high performance with an excellent Faradaic efficiency as high as 37.8% and a large yield of 18.9 µg·h−1µmgcat.−1 at −0.2 V. It also demonstrates outstanding stability in long-term electrolysis test at least for 45 h. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of NO offers us an attractive alternative to traditional selective catalytic reduction process for harmful NO removal and simultaneous NH3 production, but it requires efficient electrocatalyst to enable the NO reduction reaction with high selectivity. Here, we report on the development of Bi nanoparticles/carbon nanosheet composite (Bi@C) for highly effective NO reduction electrocatalysis toward selective NH3 formation. Such Bi@C catalyst attains an impressive NH3 yield of 1,592.5 µg·hr−1·mgcat.−1 and a high Faradaic efficiency as high as 93% in 0.1 M Na2SO4 electrolyte. Additionally, it can be applied as efficient cathode materials for Zn−NO battery to reduce NO to NH3 with high electricity generation. [ABSTRACT FROM AUTHOR]

Cardiac damage in non-severe patients with coronavirus disease 2019 (COVID-19) is poorly explored. This study aimed to explore the manifestations of cardiac damage at presentation in non-severe patients with COVID-19. In this study, 113 non-severe patients with COVID-19 were grouped according to the duration from symptoms onset to hospital admission: group 1 (≤ 1 week, n = 27), group 2 (> 1 to 2 weeks, n = 28), group 3 (> 2 to 3 weeks, n = 27), group 4 (> 3 weeks, n = 31). Clinical, cardiovascular, and radiological data on hospital admission were compared across the four groups. The level of high sensitivity troponin I (hs-cTnI) in group 2 [10.25 (IQR 6.75–15.63) ng/L] was significantly higher than those in group 1 [1.90 (IQR 1.90–8.80) ng/L] and group 4 [1.90 (IQR 1.90–5.80) ng/L] (all Pbonferroni < 0.05). The proportion of patients who had a level of hs-cTnI ≥ 5 ng/L in group 2 (85.71%) was significantly higher than those in the other three groups (37.04%, 51.85%, and 25.81%, respectively) (all Pbonferroni < 0.05). Compared with patients with hs-cTnI under 5 ng/L, those with hs-cTnI ≥ 5 ng/L had lower lymphocyte count (P = 0.000) and SpO2 (P = 0.002) and higher CRP (P = 0.000). Patients with hs-cTnI ≥ 5 ng/L had a higher incidence of bilateral pneumonia (P = 0.000) and longer hospital length of stay (P = 0.000). In conclusion, non-severe patients with COVID-19 in the second week after symptoms onset were most likely to suffer cardiac damage. A detectable level of hs-cTnI ≥ 5 ng/L might be a manifestation of early cardiac damage in the patients. [ABSTRACT FROM AUTHOR]

Information on the clinical staging of coronavirus disease 2019 (COVID-19) is still limited. This study aimed to propose a clinical staging proposal of the disease course in non-severe patients with COVID-19. In this retrospective study, 108 non-severe patients with COVID-19 were grouped according to the duration from symptoms onset to hospital admission: ≤ 1 week, > 1 to 2 weeks, > 2 to 3 weeks, > 3 to 5 weeks, respectively. The dynamic changes of clinical signs were profiled across the four groups. A clinical staging proposal of the disease course over time was proposed from the perspective of the interaction between the virus and host. The prodromal phase, characterized by pneumonia, significant lymphopenia, and slightly elevated inflammatory markers, occurred in the first week after symptoms onset. In the second week, all the hematological and inflammatory markers were at the peak or bottom. Meanwhile, progressive pneumonia as well as the secondary damage of other organs (e.g. cardiac damage, coagulopathy, etc.) was significant during this period, making the disease progress into the apparent manifestation phase. In the third week, the improvement of the majority of clinical signs accompanied by a relatively high degree of inflammatory response defined the remission phase. After 3 weeks, patients were in the convalescent phase, in which all the indicators were maintained at a relatively normal level. We concluded that the disease course over time in non-severe patients with COVID-19 could be divided into four phases: the prodromal phase (in the first week), the apparent manifestation phase (in the second week), the remission phase (in the third week), and the convalescent phase (after 3 weeks), respectively. In clinical practice, tailored therapies should be considered seriously in different stages of the disease course. [ABSTRACT FROM AUTHOR]

Objective: To compare the agreement between ultrasound-derived fat fraction (UDFF) with magnetic resonance proton density fat fraction (MRI-PDFF) for quantification of hepatic steatosis and verify its reliability and diagnostic performance by comparing with MRI-PDFF as the reference standard.This prospective study included a primary analysis of 191 patients who underwent MRI-PDFF and UDFF from February 2023 to February 2024. MRI-PDFF were derived from three liver segment measurements with calculation of an overall median PDFF. UDFF was performed by two different sonographers for each of the six measurements, and the median was taken. Intraclass correlation coefficient (ICC) and Bland–Altman analysis were used to assess agreement. Receiver operating characteristics (ROC) curves were used to evaluate the diagnostic performance of UDFF in detecting different degrees of hepatic steatosis.A total of 176 participants were enrolled in the final cohort of this study (median age, 36.0 years; 82 men, 94 women). The median MRI-PDFF value was 11.3% (interquartile range (IQR) 7.5–18.9); 84.7% patients had a median MRI-PDFF value ≥ 6.4%. The median UDFF measured by different sonographers were 9.5% (IQR: 5.0–18.0) and 9.0% (IQR: 5.0–18.0), respectively. The interobserver agreement of UDFF measurement was excellent agreement (ICC = 0.951 [95% CI: 0.934–0.964], p < 0.001). UDFF was positively strongly correlated with MRI-PDFF with ICC of 0.899 (95% CI: 0.852–0.930). The Bland–Altman analysis showed high agreement between UDFF and MRI-PDFF measurements, with a mean bias of 1.7% (95% LOA, −8.7 to 12.2%). The optimal UDFF cutoff values were 5.5%, 15.5% and 17.5% for detecting MRI-PDFF at historic thresholds of 6.4%, 17.4%, and 22.1%, with AUC of 0.851, 0.952, and 0.948, respectively. The sensitivity was 79.2%, 87.5%, 88.9%, and specificity was 81.5%, 90.6%, 90.0%, respectively.UDFF is a reliable and accurate method for quantification and classification of hepatic steatosis, with strong agreement to MRI-PDFF. The UDFF cutoff values of 5.5%, 15.5%, and 17.5% provide high sensitivity and specificity for the detection of mild, moderate, and severe hepatic steatosis, respectively.QuestionIs ultrasound-derived fat fraction (UDFF) reliable for the quantitative detection of hepatic steatosis compared to MRI proton density fat fraction (MRI-PDFF)?FindingsUDFF cutoff values of 5.5%, 15.5%, and 17.5% provided high sensitivity and specificity for the detection of mild, moderate, and severe hepatic steatosis, respectively.Clinical relevanceUDFF is a reliable and accurate method for quantification and classification of hepatic steatosis, with strong agreement to MRI-PDFF and high reproducibility of liver fat content by different sonographers.Methods: To compare the agreement between ultrasound-derived fat fraction (UDFF) with magnetic resonance proton density fat fraction (MRI-PDFF) for quantification of hepatic steatosis and verify its reliability and diagnostic performance by comparing with MRI-PDFF as the reference standard.This prospective study included a primary analysis of 191 patients who underwent MRI-PDFF and UDFF from February 2023 to February 2024. MRI-PDFF were derived from three liver segment measurements with calculation of an overall median PDFF. UDFF was performed by two different sonographers for each of the six measurements, and the median was taken. Intraclass correlation coefficient (ICC) and Bland–Altman analysis were used to assess agreement. Receiver operating characteristics (ROC) curves were used to evaluate the diagnostic performance of UDFF in detecting different degrees of hepatic steatosis.A total of 176 participants were enrolled in the final cohort of this study (median age, 36.0 years; 82 men, 94 women). The median MRI-PDFF value was 11.3% (interquartile range (IQR) 7.5–18.9); 84.7% patients had a median MRI-PDFF value ≥ 6.4%. The median UDFF measured by different sonographers were 9.5% (IQR: 5.0–18.0) and 9.0% (IQR: 5.0–18.0), respectively. The interobserver agreement of UDFF measurement was excellent agreement (ICC = 0.951 [95% CI: 0.934–0.964], p < 0.001). UDFF was positively strongly correlated with MRI-PDFF with ICC of 0.899 (95% CI: 0.852–0.930). The Bland–Altman analysis showed high agreement between UDFF and MRI-PDFF measurements, with a mean bias of 1.7% (95% LOA, −8.7 to 12.2%). The optimal UDFF cutoff values were 5.5%, 15.5% and 17.5% for detecting MRI-PDFF at historic thresholds of 6.4%, 17.4%, and 22.1%, with AUC of 0.851, 0.952, and 0.948, respectively. The sensitivity was 79.2%, 87.5%, 88.9%, and specificity was 81.5%, 90.6%, 90.0%, respectively.UDFF is a reliable and accurate method for quantification and classification of hepatic steatosis, with strong agreement to MRI-PDFF. The UDFF cutoff values of 5.5%, 15.5%, and 17.5% provide high sensitivity and specificity for the detection of mild, moderate, and severe hepatic steatosis, respectively.QuestionIs ultrasound-derived fat fraction (UDFF) reliable for the quantitative detection of hepatic steatosis compared to MRI proton density fat fraction (MRI-PDFF)?FindingsUDFF cutoff values of 5.5%, 15.5%, and 17.5% provided high sensitivity and specificity for the detection of mild, moderate, and severe hepatic steatosis, respectively.Clinical relevanceUDFF is a reliable and accurate method for quantification and classification of hepatic steatosis, with strong agreement to MRI-PDFF and high reproducibility of liver fat content by different sonographers.Results: To compare the agreement between ultrasound-derived fat fraction (UDFF) with magnetic resonance proton density fat fraction (MRI-PDFF) for quantification of hepatic steatosis and verify its reliability and diagnostic performance by comparing with MRI-PDFF as the reference standard.This prospective study included a primary analysis of 191 patients who underwent MRI-PDFF and UDFF from February 2023 to February 2024. MRI-PDFF were derived from three liver segment measurements with calculation of an overall median PDFF. UDFF was performed by two different sonographers for each of the six measurements, and the median was taken. Intraclass correlation coefficient (ICC) and Bland–Altman analysis were used to assess agreement. Receiver operating characteristics (ROC) curves were used to evaluate the diagnostic performance of UDFF in detecting different degrees of hepatic steatosis.A total of 176 participants were enrolled in the final cohort of this study (median age, 36.0 years; 82 men, 94 women). The median MRI-PDFF value was 11.3% (interquartile range (IQR) 7.5–18.9); 84.7% patients had a median MRI-PDFF value ≥ 6.4%. The median UDFF measured by different sonographers were 9.5% (IQR: 5.0–18.0) and 9.0% (IQR: 5.0–18.0), respectively. The interobserver agreement of UDFF measurement was excellent agreement (ICC = 0.951 [95% CI: 0.934–0.964], p < 0.001). UDFF was positively strongly correlated with MRI-PDFF with ICC of 0.899 (95% CI: 0.852–0.930). The Bland–Altman analysis showed high agreement between UDFF and MRI-PDFF measurements, with a mean bias of 1.7% (95% LOA, −8.7 to 12.2%). The optimal UDFF cutoff values were 5.5%, 15.5% and 17.5% for detecting MRI-PDFF at historic thresholds of 6.4%, 17.4%, and 22.1%, with AUC of 0.851, 0.952, and 0.948, respectively. The sensitivity was 79.2%, 87.5%, 88.9%, and specificity was 81.5%, 90.6%, 90.0%, respectively.UDFF is a reliable and accurate method for quantification and classification of hepatic steatosis, with strong agreement to MRI-PDFF. The UDFF cutoff values of 5.5%, 15.5%, and 17.5% provide high sensitivity and specificity for the detection of mild, moderate, and severe hepatic steatosis, respectively.QuestionIs ultrasound-derived fat fraction (UDFF) reliable for the quantitative detection of hepatic steatosis compared to MRI proton density fat fraction (MRI-PDFF)?FindingsUDFF cutoff values of 5.5%, 15.5%, and 17.5% provided high sensitivity and specificity for the detection of mild, moderate, and severe hepatic steatosis, respectively.Clinical relevanceUDFF is a reliable and accurate method for quantification and classification of hepatic steatosis, with strong agreement to MRI-PDFF and high reproducibility of liver fat content by different sonographers.Conclusions: To compare the agreement between ultrasound-derived fat fraction (UDFF) with magnetic resonance proton density fat fraction (MRI-PDFF) for quantification of hepatic steatosis and verify its reliability and diagnostic performance by comparing with MRI-PDFF as the reference standard.This prospective study included a primary analysis of 191 patients who underwent MRI-PDFF and UDFF from February 2023 to February 2024. MRI-PDFF were derived from three liver segment measurements with calculation of an overall median PDFF. UDFF was performed by two different sonographers for each of the six measurements, and the median was taken. Intraclass correlation coefficient (ICC) and Bland–Altman analysis were used to assess agreement. Receiver operating characteristics (ROC) curves were used to evaluate the diagnostic performance of UDFF in detecting different degrees of hepatic steatosis.A total of 176 participants were enrolled in the final cohort of this study (median age, 36.0 years; 82 men, 94 women). The median MRI-PDFF value was 11.3% (interquartile range (IQR) 7.5–18.9); 84.7% patients had a median MRI-PDFF value ≥ 6.4%. The median UDFF measured by different sonographers were 9.5% (IQR: 5.0–18.0) and 9.0% (IQR: 5.0–18.0), respectively. The interobserver agreement of UDFF measurement was excellent agreement (ICC = 0.951 [95% CI: 0.934–0.964], p < 0.001). UDFF was positively strongly correlated with MRI-PDFF with ICC of 0.899 (95% CI: 0.852–0.930). The Bland–Altman analysis showed high agreement between UDFF and MRI-PDFF measurements, with a mean bias of 1.7% (95% LOA, −8.7 to 12.2%). The optimal UDFF cutoff values were 5.5%, 15.5% and 17.5% for detecting MRI-PDFF at historic thresholds of 6.4%, 17.4%, and 22.1%, with AUC of 0.851, 0.952, and 0.948, respectively. The sensitivity was 79.2%, 87.5%, 88.9%, and specificity was 81.5%, 90.6%, 90.0%, respectively.UDFF is a reliable and accurate method for quantification and classification of hepatic steatosis, with strong agreement to MRI-PDFF. The UDFF cutoff values of 5.5%, 15.5%, and 17.5% provide high sensitivity and specificity for the detection of mild, moderate, and severe hepatic steatosis, respectively.QuestionIs ultrasound-derived fat fraction (UDFF) reliable for the quantitative detection of hepatic steatosis compared to MRI proton density fat fraction (MRI-PDFF)?FindingsUDFF cutoff values of 5.5%, 15.5%, and 17.5% provided high sensitivity and specificity for the detection of mild, moderate, and severe hepatic steatosis, respectively.Clinical relevanceUDFF is a reliable and accurate method for quantification and classification of hepatic steatosis, with strong agreement to MRI-PDFF and high reproducibility of liver fat content by different sonographers.Key Points: To compare the agreement between ultrasound-derived fat fraction (UDFF) with magnetic resonance proton density fat fraction (MRI-PDFF) for quantification of hepatic steatosis and verify its reliability and diagnostic performance by comparing with MRI-PDFF as the reference standard.This prospective study included a primary analysis of 191 patients who underwent MRI-PDFF and UDFF from February 2023 to February 2024. MRI-PDFF were derived from three liver segment measurements with calculation of an overall median PDFF. UDFF was performed by two different sonographers for each of the six measurements, and the median was taken. Intraclass correlation coefficient (ICC) and Bland–Altman analysis were used to assess agreement. Receiver operating characteristics (ROC) curves were used to evaluate the diagnostic performance of UDFF in detecting different degrees of hepatic steatosis.A total of 176 participants were enrolled in the final cohort of this study (median age, 36.0 years; 82 men, 94 women). The median MRI-PDFF value was 11.3% (interquartile range (IQR) 7.5–18.9); 84.7% patients had a median MRI-PDFF value ≥ 6.4%. The median UDFF measured by different sonographers were 9.5% (IQR: 5.0–18.0) and 9.0% (IQR: 5.0–18.0), respectively. The interobserver agreement of UDFF measurement was excellent agreement (ICC = 0.951 [95% CI: 0.934–0.964], p < 0.001). UDFF was positively strongly correlated with MRI-PDFF with ICC of 0.899 (95% CI: 0.852–0.930). The Bland–Altman analysis showed high agreement between UDFF and MRI-PDFF measurements, with a mean bias of 1.7% (95% LOA, −8.7 to 12.2%). The optimal UDFF cutoff values were 5.5%, 15.5% and 17.5% for detecting MRI-PDFF at historic thresholds of 6.4%, 17.4%, and 22.1%, with AUC of 0.851, 0.952, and 0.948, respectively. The sensitivity was 79.2%, 87.5%, 88.9%, and specificity was 81.5%, 90.6%, 90.0%, respectively.UDFF is a reliable and accurate method for quantification and classification of hepatic steatosis, with strong agreement to MRI-PDFF. The UDFF cutoff values of 5.5%, 15.5%, and 17.5% provide high sensitivity and specificity for the detection of mild, moderate, and severe hepatic steatosis, respectively.QuestionIs ultrasound-derived fat fraction (UDFF) reliable for the quantitative detection of hepatic steatosis compared to MRI proton density fat fraction (MRI-PDFF)?FindingsUDFF cutoff values of 5.5%, 15.5%, and 17.5% provided high sensitivity and specificity for the detection of mild, moderate, and severe hepatic steatosis, respectively.Clinical relevanceUDFF is a reliable and accurate method for quantification and classification of hepatic steatosis, with strong agreement to MRI-PDFF and high reproducibility of liver fat content by different sonographers. [ABSTRACT FROM AUTHOR]