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Abstract The spliceosome executes pre-mRNA splicing through four sequential stages: assembly, activation, catalysis, and disassembly. Activation of the spliceosome, namely remodeling of the pre-catalytic spliceosome (B complex) into the activated spliceosome (Bact complex) and the catalytically activated spliceosome (B* complex), involves major flux of protein components and structural rearrangements. Relying on a splicing inhibitor, we have captured six intermediate states between the B and B* complexes: pre-Bact, Bact-I, Bact-II, Bact-III, Bact-IV, and post-Bact. Their cryo-EM structures, together with an improved structure of the catalytic step I spliceosome (C complex), reveal how the catalytic center matures around the internal stem loop of U6 snRNA, how the branch site approaches 5′-splice site, how the RNA helicase PRP2 rearranges to bind pre-mRNA, and how U2 snRNP undergoes remarkable movement to facilitate activation. We identify a previously unrecognized key role of PRP2 in spliceosome activation. Our study recapitulates a molecular choreography of the human spliceosome during its catalytic activation.

Introduction Patients with hemophilia (PWH) constantly suffer hemarthrosis, which leads to deformity of the hip joint. Therefore, PWH who are going to receive total hip arthroplasty (THA) should be exclusively treated before the surgery with careful measurement of their proximal femur. Hence, we conducted a retrospective study to explore the anatomical parameters of and differences in the proximal femur in hemophilic patients who underwent THA. Methods The retrospective study comprised data of adult patients who received total hip arthroplasty from 2020 to 2022 in the research center. Patients having a diagnosis of hemophilic arthritis and received THA were included in experimental group, and patients with hip arthritis or femoral head necrosis were taken as control group. Parameters including femoral offset, neck‐shaft angle (NSA), medullary cavity of 20 mm above mid‐lesser trochanter level (T+20), mid‐lesser trochanter level (T), and 20 mm blow it (T−20), and canal flare index (CFI), femoral cortical index (FCI) were measured on X‐ray and CT images with PACS by two independent doctors. Data was analyzed by SPSS 20. Kolmogorov–Smirnov test was used to test data normality. Student's t‐test was performed between PWH and control group. p

Accurate identification and analysis of traffic conflicts through surrogate safety measures (SSMs) are crucial for safety evaluation in road systems. Existing SSMs for conflict identification and analysis mostly consider the temporal–spatial proximity of conflicts without taking into account the severity of potential collisions. This makes SSMs unsuitable for traffic safety evaluation in complex road environments. In order to address the shortcomings above, this study first introduces a new SSM called the Potential Conflict Risk Index (PCRI). To validate the effectiveness of PCRI, the inD dataset is adopted for conflict identification comparison between time-to-collision (TTC) and PCRI. Using PCRI, this study conducts a conflict analysis in the freeway merging areas based on the data from the Outer Ring Expressway Dataset (ORED), accounting for differences between cars and trucks. The comparative results between TTC and PCRI show that PCRI can provide a more comprehensive identification of conflicts and a more accurate identification of the moment with the highest conflict risk. The results of conflict analysis suggest that conflicts occur more frequently in situations involving trucks, and these conflicts commonly occur in closer proximity to the on-ramp at freeway merging areas. The findings from this study can improve the accuracy of conflict identification under different conflict patterns, enhancing the specificity of traffic safety measures and ultimately ensuring the safety of road systems.

Abstract The informativeness of environmental, social, and governance (ESG) scores and their actual impact on firms remains understudied. To address this gap in the literature, we make theoretical predictions and conduct empirical research revealing that a high ESG score is associated with a lower probability of ESG scandals and lower stock returns during a scandal event. Our results suggest that ESG scores are heterogeneous but informative, and that a strong ESG reputation may have both positive and negative consequences for firms. Drawing on our findings, we develop a model and showcase that firms face an optimization problem when determining optimal ESG investment levels. Two equilibria may exist based on the trade-off between ESG scandal losses and ESG adjustment costs. Our model explains why certain firms make heterogeneous ESG decisions

Objective: The aim of this study was to investigate the relationship between weight-adjusted-waist index (WWI) and diabetic kidney disease in individuals afflicted with type 2 diabetes. Methods: Comprehensive data were ascertained from the National Health and Nutrition Examination Survey in 2013– March 2020. Weighted univariate, multivariate logistic regression models, subgroup analyses and tests for interaction were performed. Additionally, we employed smooth curve fitting to assess linear correlations and the threshold effects were calculated by applying a binary linear regression model. Breakpoints are identified by a model with maximum likelihood ratio and a two-step recursive approach. Receiver operating characteristic curve (ROC) along with the area under the curve (AUC) value predict the capability of WWI and body mass index for diabetic kidney disease. Results: A total of 10,661 individuals diagnosed with type 2 diabetes were included, and the overall prevalence of diabetic kidney disease was 20.74%. WWI exhibited a positive correlation with the likelihood of diabetic kidney disease in type 2 diabetes patients (OR: 1.17, 95% CI: 1.03–1.33). The results of subgroup analysis showed significant interaction for gender (P < 0.05). Among female patients, U-shaped correlations were observed with a breakpoint at 11.48. Additionally, weight-adjusted waist index (AUC = 0.664) proved to be a more effective predictor of diabetic kidney disease compared to body mass index (AUC = 0.555). Conclusion: In patients with type 2 diabetes, increased weight-adjusted-waist index is implicated with an increased risk of diabetic kidney disease. WWI can be used as a new anthropometric index to predict diabetic kidney disease, and its predictive ability is stronger than body mass index.

Cardiac tissue engineering has emerged as a promising approach for restoring the functionality of damaged cardiac tissues following myocardial infarction. To effectively replicate the native anisotropic structure of cardiac tissues in vitro, this study focused on the fabrication of micropatterned gelatin methacryloyl hydrogels with varying geometric parameters. These substrates were evaluated for their ability to guide induced pluripotent stem cell-derived cardiomyocytes (CMs). The findings demonstrate that the mechanical properties of this hydrogel closely resemble those of native cardiac tissues, and it exhibits high fidelity in micropattern fabrication. Micropatterned hydrogel substrates lead to enhanced organization, maturation, and contraction of CMs. A microgroove with 20-μm-width and 20-μm-spacing was identified as the optimal configuration for maximizing the contact guidance effect, supported by analyses of nuclear orientation and F-actin organization. Furthermore, this specific micropattern design was found to promote CMs' maturation, as evidenced by increased expression of connexin 43 and vinculin, along with extended sarcomere length. It also enhanced CMs' contraction, resulting in larger contractile amplitudes and greater contractile motion anisotropy. In conclusion, these results underscore the significant benefits of optimizing micropatterned gelatin methacryloyl for improving CMs' organization, maturation, and contraction. This valuable insight paves the way for the development of highly organized and functionally mature cardiac tissues in vitro.

Hepatitis E (Hepatitis E, HE) is an acute and chronic infectious hepatitis caused by hepatitis E virus (Hepatitis E Virus, HEV) infection, which is responsible for most acute hepatitis in the world and is a significant public health problem. The pathogen, HEV, has three Open Reading Frames (ORFs) ORF1, ORF2, and ORF3, each of which has a different function. Most of the current research is focused on ORF1 and ORF2, while the research on ORF3 is still relatively small. To provide more ideas for the study of HEV pathogenesis and the prevention and treatment of HE, this paper reviews the effects of ORF3 on the ERK pathway, growth factors, immune response, and virus release.