Nipah virus (NiV) and related viruses form a distinct henipavirus genus within the Paramyxoviridae family. NiV continues to spillover into the humans causing deadly outbreaks with increasing human-bat interaction. NiV encodes the large protein (L) and phosphoprotein (P) to form the viral RNA polymerase machinery. Their sequences show limited homologies to those of non-henipavirus paramyxoviruses. We report two cryo-electron microscopy (cryo-EM) structures of the Nipah virus (NiV) polymerase L-P complex, expressed and purified in either its full-length or truncated form. The structures resolve the RNA-dependent RNA polymerase (RdRp) and polyribonucleotidyl transferase (PRNTase) domains of the L protein, as well as a tetrameric P protein bundle bound to the L-RdRp domain. L-protein C-terminal regions are unresolved, indicating flexibility. Two PRNTase domain zinc-binding sites, conserved in most Mononegavirales, are confirmed essential for NiV polymerase activity. The structures further reveal anchoring of the P protein bundle and P protein X domain (XD) linkers on L, via an interaction pattern distinct among Paramyxoviridae. These interactions facilitate binding of a P protein XD linker in the nucleotide entry channel and distinct positioning of other XD linkers. We show that the disruption of the L-P interactions reduces NiV polymerase activity. The reported structures should facilitate rational antiviral-drug discovery and provide a guide for the functional study of NiV polymerase.
Nipah Virus/chemistry* ; Cryoelectron Microscopy ; Viral Proteins/genetics* ; RNA-Dependent RNA Polymerase/genetics* ; Phosphoproteins/genetics* ; Humans ; Models, Molecular ; Protein Binding

Aldehyde oxidase (AOX) is a molybdoenzyme that is primarily expressed in the liver and is involved in the metabolism of drugs and other xenobiotics. AOX-mediated metabolism can result in unexpected outcomes, such as the production of toxic metabolites and high metabolic clearance, which can lead to the clinical failure of novel therapeutic agents. Computational models can assist medicinal chemists in rapidly evaluating the AOX metabolic risk of compounds during the early phases of drug discovery and provide valuable clues for manipulating AOX-mediated metabolism liability. In this study, we developed a novel graph neural network called AOMP for predicting AOX-mediated metabolism. AOMP integrated the tasks of metabolic substrate/non-substrate classification and metabolic site prediction, while utilizing transfer learning from ¹³C nuclear magnetic resonance data to enhance its performance on both tasks. AOMP significantly outperformed the benchmark methods in both cross-validation and external testing. Using AOMP, we systematically assessed the AOX-mediated metabolism of common fragments in kinase inhibitors and successfully identified four new scaffolds with AOX metabolism liability, which were validated through in vitro experiments. Furthermore, for the convenience of the community, we established the first online service for AOX metabolism prediction based on AOMP, which is freely available at https://aomp.alphama.com.cn.

Background/Aims: Metabolic dysfunction-associated steatotic liver disease (MASLD) has become an increasingly important health challenge, with a substantial rise linked to changing lifestyles and global obesity. Ursolic acid, a natural pentacyclic triterpenoid, has been explored for its potential therapeutic effects. Given its multifunctional bioactive properties, this research further revealed the pharmacological mechanisms of ursolic acid on MASLD. Methods: Drug target chips and bioinformatics analysis were combined in this study to explore the potential therapeutic effects of ursolic acid on MASLD. Molecular docking simulations, surface plasmon resonance analyses, pull-down experiments, and co-immunoprecipitation assays were used to verify the direct interactions. Gene knockdown mice were generated, and high-fat diets were used to validate drug efficacy. Furthermore, initial CD4+ T cells were isolated and stimulated to demonstrate our findings. Results: In this study, the multifunctional extracellular matrix phosphorylated glycoprotein secreted phosphoprotein 1 (SPP1) was investigated, highlighting its capability to induce Th17 cell differentiation, amplifying inflammatory cascades, and subsequently promoting the evolution of MASLD. In addition, this study revealed that in addition to the canonical TGF-β/IL-6 cytokine pathway, SPP1 can directly interact with ITGB1 and CD44, orchestrating Th17 cell differentiation via their joint downstream ERK signaling pathway. Remarkably, ursolic acid intervention notably suppressed the protein activity of SPP1, suggesting a promising avenue for ameliorating the immunoinflammatory trajectory in MASLD progression. Conclusions Ursolic acid could improve immune inflammation in MASLD by modulating SPP1-mediated Th17 cell differentiation via the ERK signaling pathway, which is orchestrated jointly by ITGB1 and CD44, emerging as a linchpin in this molecular cascade.

Objective:To evaluate whether underdilated stent could reduce the occurrence of hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS) creation.Methods:A total of 197 patients with decompensated liver cirrhosis, who had underwent TIPS creation at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, were analyzed retrospectively, including 110 males and 87 females with age 25-79 (54±11) years old. Uncovered and covered stents with 8 mm diameter were implanted in all subjects, and then dilated by balloon catheters with 6 mm or 8 mm diameter. The patients were divided into two groups, including underdilated group (6 mm, n=105) and control group (8 mm, n=92).Kaplan-Meier curves were used to illustrate cumulative rate of HE, and the differences were assessed with the log-rank test. Multivariate analyses with a Cox regression model were conducted to explore the risk factors for HE. Results:During a median follow-up period of 29 (12-54) months, 16 (15.2%) patients developed HE in the underdilated group and 27 (29.3%) patients in the control group. There was a significant difference in the cumulative rate of HE ( P=0.014), but no statistical differences were found in terms of variceal rebleeding, shunt dysfunction and survival between the two groups ( P=0.608, P=0.659, P=0.968). In multivariated analysis, group assignment (underdilated vs. control, HR=0.291, 95% CI 0.125-0.674, P=0.004) was identified as an independent risk factor for HE after TIPS creation. Conclusion:Underdilated TIPS could reduced the risk of HE compared with completely dilated TIPS, with comparable risk of variceal rebleeding, shunt dysfunction and mortality. And it is worthy of applying this technique to a large sample of patients in clinical practice.

Objective: To evaluate the efficacy and safety of portal vein stenting combined with 125I particle strand implantation followed by drug-eluting beads transarterial chemoembolization (DEB-TACE) and molecular-targeted therapy for the treatment of stageⅢa liv-er cancer lacking a blood supply. Methods: A retrospective analysis of 11 patients who had stageⅢa liver cancer lacking a blood sup-ply combined with portal vein tumor thrombosis (PVTT) was conducted from October 2016 to October 2018. All the patients under-went portal vein stenting combined with 125I particle strand implantation, DEB-TACE, and comprehensive treatment containing molecu-lar-targeted drugs. During the follow-up period, all patients were evaluated for stent patency after the implantation and tumor re-sponse after DEB-TACE treatment. The liver function and blood routine changes before and 1 month after the surgery were completed, and the complications were summarized. Results: All 11 patients were judged as stageⅢa liver cancer based on the Chinese staging criteria (2017), Child-Pugh classification grade A and B. The imaging findings indicated that these tumors were hypovascular. The maxi-mum diameter of these lesions was (8.4±4.1) (2.8-14.1) cm, and all patients had PVTT. Among them, there were 4 cases of Cheng's typeⅡand 7 cases of typeⅢ: 6 cases of main PVTT≥50% and 1 case of PVTT<50%. All patients underwent portal vein stenting com-bined with 125I particle strand implantation, DEB-TACE, and comprehensive treatment containing molecular-targeted drugs. Three and 6 months after stent implantation, the patency rate was 100%; 3 months after DEB-TACE treatment, complete response was achieved in 4 (36.4%) patients, partial response was achieved in 5 (45.5%) patients, and stable disease was achieved in 2 (18.2%) patients. No patients exhibited progressive disease. Therefore, the objective response rate was 81.8% and disease control rate was 100%. As for the liver and kidney function and blood routine tests, there were no significant differences between baseline and 1 month after the sur- gery. In addition, no patient had any serious complication during the perioperative period. Conclusions: For patients with stageⅢa liv-er cancer lacking a blood supply and PVTT, a comprehensive treatment strategy including portal vein stenting combined with 125I parti-cle strand implantation, DEB-TACE, and molecular-targeted therapy can restore portal vein blood flow and maintain mid-and long-term stent patency, while effectively killing tumors and controlling tumor growth, which is a safe and effective treatment strategy.

Objective To evaluate the effectiveness of three neurological assessments in experimental autoim?mune encephalomyelitis. Methods Thirty-two female C57BL/6 mice (18-20g) were randomly divided into normal group (n=15) and immune group (n=17). Immune group were induced subcutaneously in the flank by emulsion consisted of MOG33-35 and complete Freund’s adjuvant. Mice were assessed by two investigators for 35 days after immunization in a blinded manner using Kono’s 5-point criterion, Weaver’s 15-point criterion and improved 15-point criterion. Based on H&E staining, we analyzed the accuracy, sensibility and dependency of three assessments. Results 35-day clini?cal-score plots revealed that the fluctuation of symptoms was more obvious in improved 15-point criterion compared with the other two criteria. 15-point criterion and improved 15-point criterion are more accurate than 5-point criterion in atypical-onset EAE. 15-point criterion and improved 15-point criterion could detect the neurological deficits much earli?er than 5-point criterion (P<0.001). Neurological scores assessed by improved 15-point were well correlated with the pathological findings during the peak and remission stage. Conclusion Improved 15-point criterion is better neurological score system than Kono’s 5-point criterion and Weaver’s 15-point criterion because of its accurate assessment of the neurological deficits in experimental autoimmune encephalomyelitis.

Objective To study the role of bone morphogenetic protein-7 in the osteogenic differentiation of periosteal cellsin vitro. Methods Periosteal cells, obtained from adult tibial periosteum, were cultured by routine method in vitro, and divided into two groups. One group cultured with BMP7 and the supplements of 100 nmol dexametasone, 10 mmol b-glycerophosphate and 50 mg/mL L-ascorbic acid (BMP7 group), the other cultured with the supplements alone as the control (control group). Ultrastructure and morphological changes of periosteal cells were observed by contrast phase microscope and electron microscope. In order to test the expression of markers of osteoblastic differantiation in periosteal cells, involved mineralized node and alkaline phosphatase. Each group was tested at the time of 5 d, 10 d, 15 d, 20 d, respectively, using ALP kit stain and Von Kossa stain with 3 samples at each time. Results The periosteal cells cultured by routine method and induced into osteoblast differentiation with BMP7 were both growing well, in vitro. Microscope observations showed that the periosteal cells were spindle-shaped, well-stacked, transparent and three-dimensional in the early stage, and cube-shaped or puncheon shaped in the mitotic phase, gradually became wide shuttle and irregular shape with a lot secretion in telophase. The positive cells were visible by the ALP kit staining and Von Kossa staining of calcium nodules at 5 d, 10 d, 15 d and 20 d in both groups.A difference of positive rate at each time point was found between BMP7 group and control group at 5 d, 10 d, 15 d, 20 d, and the difference was statistically significant (P ＜ 0.01). Conclusion It displayed well regeneration and osteogenesis ability in the periosteal cell. BMP7 has definite osteo-inductive activity, which can obviously enhance the proliferation and ossifyng differentiation of periosteal cells.