PAFAH2 suppresses synchronized ferroptosis to ameliorate acute kidney injury.

Synchronized ferroptosis contributes to nephron loss in acute kidney injury (AKI). However, the propagation signals and the underlying mechanisms of the synchronized ferroptosis for renal tubular injury remain unresolved. Here we report that platelet-activating factor (PAF) and PAF-like phospholipids (PAF-LPLs) mediated synchronized ferroptosis and contributed to AKI. The emergence of PAF and PAF-LPLs in ferroptosis caused the instability of biomembranes and signaled the cell death of neighboring cells. This cascade could be suppressed by PAF-acetylhydrolase (II) (PAFAH2) or by addition of antibodies against PAF. Genetic knockout or pharmacological inhibition of PAFAH2 increased PAF production, augmented synchronized ferroptosis and exacerbated ischemia/reperfusion (I/R)-induced AKI. Notably, intravenous administration of wild-type PAFAH2 protein, but not its enzymatically inactive mutants, prevented synchronized tubular cell death, nephron loss and AKI. Our findings offer an insight into the mechanisms of synchronized ferroptosis and suggest a possibility for the preventive intervention of AKI.

Deep learning using contrast-enhanced ultrasound images to predict the nuclear grade of clear cell renal cell carcinoma.

PURPOSE: To assess the effectiveness of a deep learning model using contrastenhanced ultrasound (CEUS) images in distinguishing between low-grade (grade I and II) and high-grade (grade III and IV) clear cell renal cell carcinoma (ccRCC). METHODS: A retrospective study was conducted using CEUS images of 177 Fuhrmangraded ccRCCs (93 low-grade and 84 high-grade) from May 2017 to December 2020. A total of 6412 CEUS images were captured from the videos and normalized for subsequent analysis. A deep learning model using the RepVGG architecture was proposed to differentiate between low-grade and high-grade ccRCC. The model's performance was evaluated based on sensitivity, specificity, positive predictive value, negative predictive value and area under the receiver operating characteristic curve (AUC). Class activation mapping (CAM) was used to visualize the specific areas that contribute to the model's predictions. RESULTS: For discriminating high-grade ccRCC from low-grade, the deep learning model achieved a sensitivity of 74.8%, specificity of 79.1%, accuracy of 77.0%, and an AUC of 0.852 in the test set. CONCLUSION: The deep learning model based on CEUS images can accurately differentiate between low-grade and high-grade ccRCC in a non-invasive manner.

A novel model based on liver/spleen volumes and portal vein diameter on MRI to predict variceal bleeding in HBV cirrhosis.

OBJECTIVE: To develop a novel logistic regression model based on liver/spleen volumes and portal vein diameter measured on magnetic resonance imaging (MRI) for predicting oesophagogastric variceal bleeding (OVB) secondary to HBV cirrhosis. METHODS: One hundred eighty-five consecutive cirrhotic patients with hepatitis B undergoing abdominal contrast-enhanced MRI were randomly divided into training cohort (n = 130) and validation cohort (n = 55). Spleen volume, total liver volume, four liver lobe volumes, and diameters of portal venous system were measured on MRI. Ratios of spleen volume to total liver and to individual liver lobe volumes were calculated. In training cohort, univariate analyses and binary logistic regression analyses were to determine independent predictors. Performance of the model for predicting OVB constructed based on independent predictors from training cohort was evaluated by receiver operating characteristic (ROC) analysis, and was validated by Kappa test in validation cohort. RESULTS: OVB occurred in 42 and 18 individuals in training and validation cohorts during the 2 years' follow-up, respectively. An OVB prediction model was constructed based on the independent predictors including right liver lobe volume (RV), left gastric vein diameter (LGVD) and portal vein diameter (PVD) (odds ratio = 0.993, 2.202 and 1.613, respectively; p-values < 0.001 for all). The logistic regression model equation (-0.007 × RV + 0.79 × LGVD + 0.478 × PVD-6.73) for predicting OVB obtained excellent performance with an area under ROC curve of 0.907. The excellent performance was confirmed by Kappa test with K-value of 0.802 in validation cohort. CONCLUSION: The novel logistic regression model can be reliable for predicting OVB. KEY POINTS: • Patients with oesophagogastric variceal bleeding are mainly characterized by decreased right lobe volume, and increased spleen volume and diameters of portal vein system. • The right liver lobe volume, left gastric vein diameter and portal vein diameter are the independent predictors of oesophagogastric variceal bleeding. • The novel model developed based on the independent predictors performed well in predicting oesophagogastric variceal bleeding with an area under the receiver operating characteristic curve of 0.907.

Forensic age prediction and age classification for critical age thresholds via 3.0T magnetic resonance imaging of the knee in the Chinese Han population.

OBJECTIVES: To assess the performance of knee MRI for forensic age prediction and classification for 12-, 14-, 16-, and 18-year thresholds. METHODS: The ossification stages of distal femoral epiphyses and proximal tibial epiphyses were assessed using an integrated staging system by Schmeling et al. and Kellinghaus et al. for knee 3.0T MRI with T1-weighted turbo spin-echo (T1-TSE) in sagittal orientation among 852 Chinese Han individuals (483 males and 369 females) aged 7-30 years. Regression models for age prediction were constructed and their performances were evaluated based on mean absolute deviation (MAD) values. In addition, the performances of age classification were assessed using receiver operating characteristic (ROC) analyses. RESULTS: The intra- and inter-observer agreement levels were very good (κ > 0.80). The complete fusion of those two types of epiphyses took place before 18.0 years in our study participants. The minimum MAD values were 2.51 years (distal femur) and 2.69 years (proximal tibia) in males, and 2.75 years (distal femur) and 2.87 years (proximal tibia) in females. The specificity values of constructed prediction models were all above 90% for the 12-, 14-, and 16-year thresholds, compared to the 74.8-84.6% for the 18-year threshold. Better performances of age prediction and classification were observed in males by distal femoral epiphyses. CONCLUSIONS: Ossification stages via 3.0T MRI of the knee with T1-TSE sequence using an integrated staging system could be a reliable noninvasive method for age prediction or for age classification for 12-, 14-, and 16-year thresholds, especially in males by distal femoral epiphyses. However, assessments based on the full bony fusion of the distal femoral epiphysis and proximal tibial epiphysis seemed not reliable for age classification for the 18-year threshold in the Chinese Han population.

Black phosphorene/NP heterostructure as a novel anode material for Li/Na-ion batteries.

Designing heterostructured anode materials has been rendered supremely appealing to large-scale energy storage systems and storage device researchers. Recently, black phosphorene has experienced explosive development and been sought for widespread application in various domains including anode materials for electrochemistry. Hence, in this work, the black phosphorene/NP heterostructure (black P/NP) as a novel anode material for Li/Na batteries was systematically studied on the basis of first-principle calculations. Our simulations disclose that black P/NP is dynamically stable at room temperature and exhibits metallic properties. Charge density difference calculations and work function analysis demonstrate that electron charge transfer between the pristine single-layer components leads to enhanced Li/Na ion adsorption on the interlayer. To be specific, the calculated adsorption energies for Li/Na are -2.27 and -2.13 eV, respectively, which are sufficient to prevent metal aggregation during cycling. Besides, it is predicated that black P/NP has a positive and low open-circuit voltage. Excitingly, the diffusion barriers for Li and Na ions on black P/NP are 0.17 and 0.04 eV, respectively, which are superior to other typical heterostructures. Our results may be a new paradigm and reference for phosphorene-based heterostructures used as electrode materials of metal-ion batteries.

NP monolayer supported transition-metal single atoms for electrochemical water splitting: a theoretical study.

The development of cost-effective and highly efficient electrocatalysts for water splitting is highly desirable but remains an ongoing challenge. Numerous single-atom catalysts (SACs) have achieved satisfactory performances in this area; however, non-carbon metal-free substrates have been rarely explored. Herein, we report a series of single-metal atoms supported on a novel two-dimensional NP monolayer as promising electrocatalysts for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) by theoretical calculations. Our results disclose that Ti@NP, V@NP and Ir@NP exhibit desirable catalytic activity for the HER with extremely low of -0.004, -0.051, and 0.017 eV, respectively. More importantly, the calculated activation barriers for the Tafel reactions of these SACs are much lower than those for the benchmark Pt catalysts. In addition, Pt@NP shows the lowest ηOER of 0.495 V, followed by Rh@NP (ηOER = 0.548 V), which are even superior to that of state-of-the-art IrO2. This work highlights the potential application of metal-free supports in SACs, which also further enriches the application of a NP monolayer in other related electrochemical processes.

Nb2N monolayer as a promising anode material for Li/Na/K/Ca-ion batteries: a DFT calculation.

Developing ranking anode materials with sufficient electrical conductivity, ultrafast ion diffusion ability and considerable storage capacity is of great importance for rechargeable ion batteries but still challenging. Herein, using first-principles calculations, the potential of monolayer Nb2N as an anode material for alkali metal (e.g., Li, Na, K and Ca) ion batteries (LIBs, SIBs, PIBs and CIBs) has been explored. The calculated results indicate that the Nb2N monolayer is dynamically and thermally stable with excellent electronic conductivity. To be specific, the Li, Na, K and Ca atoms can be steadily adsorbed on the Nb2N monolayer with a low adsorption energy of -0.996, -1.263, -1.568, and -1.401 eV, respectively. Impressively, the calculated low diffusion barriers for Li, Na, K and Ca on the Nb2N monolayer are 0.047, 0.029, 0.015 and 0.051 eV, respectively, implying its high performance for the ultrafast charge and discharge processes. More importantly, the maximum storage capacities are 536 mA h g-1 for LIBs and 1072 mA h g-1 for CIBs, which are much larger than those of common anode materials. This work not only demonstrates that the Nb2N monolayer can be used as a promising anode material but also inspires the future rational design of other nitride MXenes in energy conversion and storage devices.

Radiomics model of contrast-enhanced MRI for early prediction of acute pancreatitis severity.

BACKGROUND: Computed tomography (CT) or MR images may cause the severity of early acute pancreatitis (AP) to be underestimated. As an innovative image analysis method, radiomics may have potential clinical value in early prediction of AP severity. PURPOSE: To develop a contrast-enhanced (CE) MRI-based radiomics model for the early prediction of AP severity. STUDY TYPE: Retrospective. SUBJECTS: A total of 259 early AP patients were divided into two cohorts, a training cohort (99 nonsevere, 81 severe), and a validation cohort (43 nonsevere, 36 severe). FIELD STRENGTH/SEQUENCE: 3.0T, T1 -weighted CE-MRI. ASSESSMENT: Radiomics features were extracted from the portal venous-phase images. The "Boruta" algorithm was used for feature selection and a support vector machine model was established with optimal features. The MR severity index (MRSI), the Acute Physiology and Chronic Health Evaluation (APACHE) II, and the bedside index for severity in acute pancreatitis (BISAP) were calculated to predict the severity of AP. STATISTICAL TESTS: Independent t-test, Mann-Whitney U-test, chi-square test, Fisher's exact tests, Boruta algorithm, receiver operating characteristic analysis, DeLong test. RESULTS: Eleven potential features were chosen to develop the radiomics model. In the training cohort, the area under the curve (AUC) of the radiomics model, APACHE II, BISAP, and MRSI were 0.917, 0.750, 0.744, and 0.749, and the P value of AUC comparisons between the radiomics model and scoring systems were all less than 0.001. In the validation cohort, the AUC of the radiomics model, APACHE II, BISAP, and MRSI were 0.848, 0.725, 0.708, and 0.719, respectively, and the P value of AUC comparisons were 0.96 (radiomics vs. APACHE II), 0.40 (radiomics vs. BISAP), and 0.46 (radiomics vs. MRSI). DATA CONCLUSION: The radiomics model had good performance in the early prediction of AP severity. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:397-406.

Non-Metal Single-Phosphorus-Atom Catalysis of Hydrogen Evolution.

Non-metal-based single-atom catalysts (SACs) offer low cost, simple synthesis methods, and effective regulation for substrates. Herein, we developed a simplified pressurized gas-assisted process, and report the first non-metal single-atom phosphorus with atomic-level dispersion on unique single-crystal Mo2 C hexagonal nanosheet arrays with a (001) plane supported by carbon sheet (SAP-Mo2 C-CS). The SAP-Mo2 C-CS is structurally stable and shows exceptional electrocatalytic activity for the hydrogen evolution reaction (HER). A so-called high-active "window" based on the active sites of P atoms and their adjacent Mo atoms gives a ΔGH* close to zero for hydrogen evolution, which is the most ideal ΔGH* reported so far. Meanwhile, the moderate d-band center value of SAP-Mo2 C-CS can be also used as an ideal standard value to evaluate the HER performance in non-metal-based SACs.

Radiomics model of contrast-enhanced computed tomography for predicting the recurrence of acute pancreatitis.

OBJECTIVES: To predict the recurrence of acute pancreatitis (AP) by constructing a radiomics model of contrast-enhanced computed tomography (CECT) at AP first attack. METHODS: We retrospectively enrolled 389 first-attack AP patients (271 in the primary cohort and 118 in the validation cohort) from three tertiary referral centers; 126 and 55 patients endured recurrent attacks in each cohort. Four hundred twelve radiomics features were extracted from arterial and venous phase CECT images, and clinical characteristics were gathered to develop a clinical model. An optimal radiomics signature was chosen using a multivariable logistic regression or support vector machine. The radiomics model was developed and validated by incorporating the optimal radiomics signature and clinical characteristics. The performance of the radiomics model was assessed based on its calibration and classification metrics. RESULTS: The optimal radiomics signature was developed based on a multivariable logistic regression with 10 radiomics features. The classification accuracy of the radiomics model well predicted the recurrence of AP for both the primary and validation cohorts (87.1% and 89.0%, respectively). The area under the receiver operating characteristic curve (AUC) of the radiomics model was significantly better than that of the clinical model for both the primary (0.941 vs. 0.712, p = 0.000) and validation (0.929 vs. 0.671, p = 0.000) cohorts. Good calibration was observed for all the models (p > 0.05). CONCLUSIONS: The radiomics model based on CECT performed well in predicting AP recurrence. As a quantitative method, radiomics exhibits promising performance in terms of alerting recurrent patients to potential precautions. KEY POINTS: • The incidence of recurrence after an initial episode of acute pancreatitis is high, and quantitative methods for predicting recurrence are lacking. • The radiomics model based on contrast-enhanced computed tomography performed well in predicting the recurrence of acute pancreatitis. • As a quantitative method, radiomics exhibits promising performance in terms of alerting recurrent patients to the potential need to take precautions.

MR imaging of hemorrhage associated with acute pancreatitis.

PURPOSE: To study MRI findings of hemorrhage in acute pancreatitis (AP) and correlate the presence and extent of hemorrhage with the MR severity index (MRSI), Acute Physiology And Chronic Health Evaluation (APACHE) II scores, and clinical outcome. MATERIALS AND METHODS: This retrospective study included 539 patients with AP. Hemorrhage was defined as areas of hyperintensity in or outside the pancreas on liver imaging with volume acceleration flexible (LAVA-Flex). The presence of hemorrhage was classified into three areas: within the pancreatic parenchyma, retroperitoneal space, and sub-or intraperitoneal space. Involvement of each area was awarded 1 point resulting in the hemorrhage severity index (HSI) score. The predicted severity of AP was graded by MRSI and APACHE II score. The association between HSI, MRSI, and APACHE II scores was analyzed. The length of hospital stay and organ dysfunction was used as clinical outcome parameters. RESULTS: Among 539 AP patients, 62 (11.5%) had hemorrhage. The prevalence of hemorrhage was 1.1% (2/186), 13.9% (43/310), and 39.5% (17/43) in predicted mild, moderate, and severe AP, respectively, based on MRSI (χ2 = 55.3, p = 0.00); and 7.7% (21/273) and 19.2% (18/94) in predicted mild and severe AP, respectively, based on APACHE II (χ2 = 21.2, p = 0.00). HSI score significantly correlated with MRSI (r = 0.36, p < 0.001) and APACHE II scores (r = 0.21, p = 0.00). The prevalence of organ dysfunction was higher and length of hospital stay was longer in patients with hemorrhage than in those without hemorrhage (p < 0.01). CONCLUSIONS: Hemorrhage in AP is common. The presence of hemorrhage, rather than its extent, correlates with poor clinical outcome.

Tumour volume of resectable oesophageal squamous cell carcinoma measured with MRI correlates well with T category and lymphatic metastasis.

OBJECTIVES: To determine association of gross tumour volume (GTV) of resectable oesophageal squamous cell carcinoma (SCC) measured on T2-weighted imaging (T2WI), contrast-enhanced T1-weighted imaging (CE-T1WI) and diffusion-weighted imaging (DWI) with T category and lymphatic metastasis (LM). METHODS: Sixty oesophageal SCC patients underwent fat-suppressed T2WI, CE-T1WI and DWI with b values of 0, 500 and 800 s/mm2. GTV was measured on three sequences. Statistical analyses were performed to determine association of GTV with T category and LM. RESULTS: Spearman's rank correlation analysis showed positive association of GTV with T category and LM (all p values < 0.01). Differences in GTV were found between T1 and T2 or T3 categories shown by Kruskal-Wallis H and one-way ANOVA tests, and between T1/T2 and T3 and between tumours with and without LM by Mann-Whitney U tests (all p values < 0.05). Receiver operating characteristic analyses showed cut-off GTVs of 5.795, 5.276 and 10.11 cm3 on CE-T1WI could better differentiate T1 from T2 categories, T1 from T3, and T1-2 from T3 than those of 7.066, 7.045 and 8.504 cm3 on T2WI, of 5.793, 6.609 and 6.989 cm3 on DWI with b value of 500 s/mm2, and of 4.156, 4.519 and 4.985 cm3 with b value of 800 s/mm2, respectively. Cut-off of 10.462 cm3 on DWI with b value of 500 s/mm2 could better identify LM than of 12.38, 8.793 and 9.600 cm3 on T2WI, CE-T1WI and DWI with b value of 800 s/mm2, respectively. CONCLUSIONS: GTVs on T2WI, CE-T1WI and DWI are associated with T category of and LM of oesophageal SCC. KEY POINTS: • GTV is associated with T category and lymphatic metastasis of oesophageal SCC • GTV measured on contrast-enhanced T 1 -weighted imaging better identifies T category • GTV measured on DWI with b value of 500 s/mm 2 better identifies lymphatic metastasis.

Low expression of long non-coding RNA GAS5 is associated with poor prognosis of patients with thyroid cancer.

The study aims to investigate the role of long non-coding RNA (lncRNA) GAS5 in the diagnosis and prognosis of patients suffering from thyroid cancer (TC). A total of 212 patients with TC and 61 patients with benign thyroid tumor were enrolled in the study. Quantitative real-time polymerase chain reaction (qRT-PCR) was applied to detect the lncRNA GAS5 expression in TC and benign tumor tissues. All TC patients were categorized into high-risk and low-risk groups according to the MACIS, AGES and AMES prognostic scoring system. A 5-year follow-up was conducted in order to determine the disease free survival (DFS) rates and overall survival (OS) rates. The associations between lncRNA GAS5 expression and prognosis of TC patients were analyzed by The Kaplan-Meier survival curves and the Cox regression models. There was a decrease in the lncRNA GAS5 expression in TC tissues in comparison to benign tumor tissues. Expression of lncRNA GAS5 showed significant association with tumor node metastasis (TNM) staging, lymph node metastasis and the multiple cancer foci of TC. AMES high-risk patients showed a decreased expression of lncRNA GAS5 expression than the AMES low-risk patients. The AGES and MACIS high-risk patients showed lower lncRNA GAS5 expression than low-risk patients. The survival rate of TC patients with high lncRNA GAS5 expression was higher than that of TC patients with low lncRNA GAS5 expression during the DFS and OS periods. Cox regression analysis indicated that lncRNA GAS5 expression, TNM staging, lymph node metastasis and multiple cancer foci were independent risk factors for poor prognosis in TC patients. LncRNA GAS5 may be closely related to the diagnosis and prognosis of TC.

Roles of microRNA-124a and microRNA-30d in breast cancer patients with type 2 diabetes mellitus.

The aim of the study is to explore roles of microRNA (miR)-124a and miR-30d in breast cancer (BC) patients with type 2 diabetes mellitus (T2DM). A total of 144 cases of confirmed diagnosed BC with T2DM, T2DM, BC, or healthy people were enrolled. Among them, BC patients with T2DM were regarded as the experiment group (n = 36), patients with T2DM as the Dm group (n = 36), patients with BC as the Bc group (n = 36), and healthy subjects as the healthy group (n = 36). The fasting insulin resistance index, glycosylated hemoglobin, and estradiol were measured. MiR-124a and miR-30d expressions were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The insulin resistance index was significantly higher in the experiment group compared to the other three groups (all P < 0.05). The glycated hemoglobin was in a normal range in the Bc group and healthy group, but was higher in the experiment group and the Bc group compared to that in the healthy group (both P < 0.05). The serum estradiol level was obviously higher in the Bc group compared with that in the Dm group and the experiment group (both P < 0.05). The expressions of miR-124a and miR-30d were positively correlated with insulin resistance index, BMI and glycosylated hemoglobin (miR-124a r = 0.659, r = 0.785, and r = 0.862; miR-30d r = 0.742, r = 0.805, r = 0.765; all P < 0.001). Insulin resistance index was an independent factor for expressions of miR124-a and miR-30d. MiR-124a and miR-30d were correlated with insulin resistance and development of BC with T2DM. Although the mechanism is not clear, miR-124a and miR-30d potentially may be used as therapeutic targets and prognostic markers for BC patients with T2DM.

Thickness of soft tissue of lower extremities measured with magnetic resonance imaging as a new indicator for staging unilateral secondary lower extremity lymphedema.

BACKGROUND: Chronic progressive swelling of the lower extremity due to secondary lower extremity lymphedema (LEL) can affect a patient's quality of life, both physically and psychologically. A feasible and reproducible method for detecting and staging LEL will facilitate decision-making about appropriate management strategies. PURPOSE: To determine whether the thickness of the soft tissues of the lower extremities, measured with magnetic resonance imaging (MRI), could stage unilateral secondary LEL. MATERIAL AND METHODS: Seventy-two women with unilateral LEL and 22 participants without LEL underwent lower extremity MRI after treatment of uterine malignancies. LEL was classified clinically as stage 0, 1, 2, or 3. On fat-suppressed T2-weighted mid-axial images of calves and thighs, the total thickness of the soft tissue (TT), muscle thickness (MT), subcutaneous tissue thickness (STT), and the differences in TT (DTT), MT (DMT), and STT (DSTT) values and corresponding measurements in the contralateral lower extremity, were obtained and analyzed statistically for staging LEL. RESULTS: There was a trend for the TT and STT of the affected calf and thigh to increase with increasing LEL stage. These parameters were strongly and moderately correlated with LEL stage, respectively (P < 0.001). Both the DTT and DSTT of the calves or thighs were strongly correlated with LEL stage (P < 0.001). Among the parameters, the DSTT of the calves could best stage LEL, with an area under the receiver operating curve of more than 0.89. CONCLUSION: The DSTT of the calves could be recommended as an informative indicator for staging LEL.

Abdominal MRI at 3.0 T: LAVA-Flex compared with conventional fat suppression T1-weighted images.

PURPOSE: To study liver imaging with volume acceleration-flexible (LAVA-Flex) for abdominal magnetic resonance imaging (MRI) at 3.0 T and compare the image quality of abdominal organs between LAVA-Flex and fast spoiled gradient-recalled (FSPGR) T1-weighted imaging. MATERIALS AND METHODS: Our Institutional Review Board approval was obtained in this retrospective study. Sixty-nine subjects had both FSPGR and LAVA-Flex sequences. Two radiologists independently scored the acquisitions for image quality, fat suppression quality, and artifacts and the values obtained were compared with the Wilcoxon signed rank test. According to the signal intensity (SI) measurements, the uniformity of fat suppression, the contrast between muscle and fat and normal liver and liver lesions were compared by the paired t-test. The liver and spleen SI on the fat-only phase were analyzed in the fatty liver patients. RESULTS: Compared with FSPGR imaging, LAVA-Flex images had better and more homogenous fat suppression and lower susceptibility artifact (qualitative scores: 4.70 vs. 4.00, 4.86% vs. 7.14%, 4.60 and 4.10, respectively). The contrast between muscle and fat and between the liver and pathologic lesions was significantly improved on the LAVA-Flex sequence. The contrast value of the fatty liver and spleen was higher than that of the liver and spleen. CONCLUSION: The LAVA-Flex sequence offers superior and more homogenous fat suppression of the abdomen than does the FSPGR sequence. The fat-only phase can be a simple and effective method of assessing fatty liver.

Liver dynamic contrast-enhanced MRI for staging liver fibrosis in a piglet model.

PURPOSE: To determine whether dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) could monitor progression of liver fibrosis in a piglet model, and which DCE-MRI parameter is most accurate for staging this disease. MATERIALS AND METHODS: Sixteen piglets were prospectively used to model liver fibrosis and underwent liver DCE-MRI followed by biopsy on the 0, 5th, 9th, 16th, and 21st weekends after modeling of fibrosis. Time of peak (TOP), time to peak (TTP), positive enhancement integral (PEI), maximum slope of increase (MSI), and maximum slope of decrease (MSD) were measured and statistically analyzed for the monitoring and staging. RESULTS: As fibrosis progresses, TOP and TTP tended to increase, whereas MSI, MSD, and PEI tended to decrease (all P < 0.05). TOP, TTP, and MSI could discriminate fibrosis stage 0 from 1-4, 0-1 from 2-4, 0-2 from 3-4, and 0-3 from 4; PEI could distinguish the above-mentioned stages except 0-3 from 4; and MSD could distinguish stage 0-3 from 4, and 0 from 1-4 (all P < 0.05). For predicting stage ≥1, ≥2, and ≥3, the area under receiver operating characteristic curve (AUC) of MSI was largest among all parameters; for stage 4 AUC of TTP was largest. CONCLUSION: DCE-MRI has the potential to dynamically stage progression of liver fibrosis.

Diameters of left gastric vein and its originating vein on magnetic resonance imaging in liver cirrhosis patients with hepatitis B: Association with endoscopic grades of esophageal varices.

AIM: To determine whether diameters of the left gastric vein (LGV) and its originating vein are associated with endoscopic grades of esophageal varices. METHODS: Ninety-eight liver cirrhotic patients with hepatitis B undergoing magnetic resonance (MR) portography, and upper gastrointestinal endoscopy for grading esophageal varices were enrolled. Diameters of the LGV and its originating vein - the splenic vein (SV) or portal vein (PV) - were measured on MR imaging. Statistical analyses were performed to identify the association of the diameters with the endoscopic grades. RESULTS: Univariate analysis showed that the SV was predominantly the originating vein of the LGV, and diameters of the LGV and SV were associated with grades of esophageal varices. Diameters of the LGV (P = 0.023, odds ratio [OR] = 1.583) and SV (P = 0.012, OR = 2.126) were independent risk factors of presence of the varices. Cut-off LGV diameters of 5.1 mm, 5.9 mm, 6.6 mm, 7.1 mm, 7.8 mm and 5.8 mm; or cut-off SV diameters of 7.3 mm, 7.9 mm, 8.4 mm, 9.5 mm, 10.7 mm and 8.3 mm, could discriminate grades 0 from 1, 0 from 2, 0 from 3, 1 from 3, 2 from 3, and 0-1 from 2-3, respectively. CONCLUSION: Diameters of the LGV and SV are associated with endoscopic grades of esophageal varices.

Validity of soft-tissue thickness of calf measured using MRI for assessing unilateral lower extremity lymphoedema secondary to cervical and endometrial cancer treatments.

AIM: To determine whether soft-tissue thickness of the calf measured using MRI could be valid for assessing unilateral lower extremity lymphoedema (LEL) secondary to cervical and endometrial cancer treatments. MATERIALS AND METHODS: Seventy women with unilateral LEL and 25 without LEL after cervical or endometrial cancer treatments underwent MRI examinations of their calves. Total thickness of soft-tissue (TT), muscle thickness (MT), and subcutaneous tissue thickness (STT) of the calf, and the difference between the affected and contralateral unaffected calf regarding TT (DTT), MT (DMT), and STT (DSTT) were obtained using fat-suppressed T2-weighted imaging in the middle of the calves. The volume of the calf and difference in volume (DV) between calves were obtained by the method of water displacement. Statistical analysis was performed to determine the validity of MRI measurements by volume measurements in staging LEL. RESULTS: There was a close correlation between volume and TT for the affected (r = 0.927) or unaffected calves (r = 0.896). STT of the affected calf, and DTT or DSTT of the calves were closely correlated with volume of the affected calf or DV of the calves (all p < 0.05). Multivariate analysis showed significant differences in TT, STT, volume of the affected calf, DTT, DSTT, and DV between stages except in volume of the affected calf or in DV between stage 0 and 1. For staging LEL, DSTT showed the best discrimination ability among all the parameters. CONCLUSIONS: Soft-tissue thickness of the calf measured at MRI could be valid for quantitatively staging unilateral LEL, and DSTT of the calves could be the best classifying factor.