Nine previously undescribed prenylated xanthones, aspxanthones A-I (1-9), were isolated and characterized from the endophytic fungus Aspergillus sp. TJ507. Their structures were established through comprehensive spectroscopic analyses, single-crystal X-ray diffraction, and DP4+ probability analysis. Compounds 1, 2, and 4 exhibited modest in vitro SIRT1 activating effects, with EC50 values ranging from 9.3 to 13.7 μM. The positive control resveratrol yielded an EC50 of 2.4 ± 0.4 μM under identical assay conditions. Molecular docking was conducted with resveratrol as a reference ligand, which revealed obvious differences in binding modes between resveratrol and the tested xanthones. To further clarify their dynamic binding behaviors, molecular dynamics simulations, free-energy landscape analysis, and MM/GBSA calculations were carried out on these active compounds. Among them, compound 4 displayed the most stable simulated binding profile and the most favorable estimated binding free energy among the three complexes, broadly consistent with the experimental activity ranking. In contrast, compound 2 exhibited higher conformational flexibility throughout the simulation, indicating a distinct binding mode. This study expands the chemical diversity of fungal-derived xanthones and provides valuable templates for the design and development of potential SIRT1 activators.
Xueqi Lan, Dong-Chun Liang, Li Tang et al.· Bioorganic chemistry (Print)· 0 citations
Character image animation remains a foundational yet challenging task in computer vision. Existing approaches can be broadly categorized into three paradigms: methods based on explicit motion representations suffer from extraction errors and identity drift; methods based on implicit motion features lose fine-grained dynamics through compression; and in-context learning approaches avoid intermediate representations but incur prohibitive computational costs. Furthermore, all current systems are designed for offline synthesis, unable to meet the real-time requirements of interactive applications such as digital avatars and live-streaming hosts. To address these limitations, we present Wan-Animate-2, an end-to-end character animation framework that directly consumes the driving video within a redesigned Diffusion Transformer. Our architecture achieves superior motion fidelity and identity preservation by eliminating intermediate motion extractors entirely. We further introduce text driven viewpoint control that decouples the output camera perspective from the driving video--a capability rarely supported by prior character animation methods that rely on explicit motion representations. Beyond generation quality, we present Wan-Animate-2-Lite, an efficient variant that reduces inference latency to real-time thresholds through a three-stage training paradigm: teacher forcing pretraining with error buffer mechanism, and Self-Forcing distillation with chunk-wise backpropagation. This enables streaming character animation for interactive applications, opening new deployment scenarios that were previously infeasible. Qualitative evaluations and user studies demonstrate that Wan-Animate-2 achieves high-fidelity animation results across diverse characters and motion patterns. To foster further research and community development, we will release the Wan-Animate-2-Base model weights to the public.
Guangyuan Wang, Liucheng Hu, Dechao Meng et al.· 0 citations
