T7 RNA polymerase (T7 RNAP) is one of the simplest known RNA polymerases. Its unique structural features make it a critical model for studying the mechanisms of RNA synthesis. This review systematically examines the static crystal structure of T7 RNAP, beginning with an in-depth examination of its characteristic “thumb”, “palm”, and “finger” domains, which form the classic “right-hand-like” architecture. By detailing these structural elements, this review establishes a foundation for understanding the overall organization of T7 RNAP. This review systematically maps the functional roles of secondary structural elements and their subdomains in transcriptional catalysis, progressively elucidating the fundamental relationships between structure and function. Further, the intrinsic flexibility of T7 RNAP and its applications in research are also discussed. Additionally, the review presents the structural diagrams of the enzyme at different stages of the transcription process, and through these diagrams, it provides a detailed description of the complete transcription process of T7 RNAP. By integrating structural dynamics and kinetics analyses, the review constructs a comprehensive framework that bridges static structure to dynamic processes. Despite its advantages, T7 RNAP has a notable limitation: it generates double-stranded RNA (dsRNA) as a byproduct. The presence of dsRNA not only compromises the purity of mRNA products but also elicits nonspecific immune responses, which pose significant challenges for biotechnological and therapeutic applications. The review provides a detailed exploration of the mechanisms underlying dsRNA formation during T7 RNAP catalysis, reviews current strategies to mitigate this issue, and highlights recent progress in the field. A key focus is the semi-rational design of T7 RNAP mutants engineered to minimize dsRNA generation and enhance catalytic performance. Beyond its role in transcription, T7 RNAP exhibits rapid development and extensive application in fields, including gene editing, biosensing, and mRNA vaccines. This review systematically examines the structure-function relationships of T7 RNAP, elucidates the mechanisms of dsRNA formation, and discusses engineering strategies to optimize its performance. It further explores the engineering optimization and functional expansion of T7 RNAP. Furthermore, this review also addresses the pressing issues that currently need resolution, discusses the major challenges in the practical application of T7 RNAP, and provides an outlook on potential future research directions. In summary, this review provides a comprehensive analysis of T7 RNAP, ranging from its structural architecture to cutting-edge applications. We systematically examine: (1) the characteristic right-hand domains (thumb, palm, fingers) that define its minimalistic structure; (2) the structure-function relationships underlying transcriptional catalysis; and (3) the dynamic transitions during the complete transcription cycle. While highlighting T7 RNAP’s versatility in gene editing, biosensing, and mRNA vaccine production, we critically address its major limitation—dsRNA byproduct formation—and evaluate engineering solutions including semi-rationally designed mutants. By synthesizing current knowledge and identifying key challenges, this work aims to provide novel insights for the development and application of T7 RNAP and to foster further thought and progress in related fields.

Skeletal muscle atrophy is characterized by a reduction in both the size and quantity of skeletal muscle fibers, resulting in impaired muscle strength and function. It mainly includes disuse muscle atrophy, aging muscle atrophy, denervated muscle atrophy and muscle atrophy caused by disease etc. As a cost-effective way, exercise has been widely used in the prevention and treatment of skeletal muscle atrophy, but its mechanism for improving skeletal muscle atrophy remains unclear. Recent studies have indicated that insulin-like growth factor 1 (IGF-1) plays an important role in improving muscle atrophy through exercise, in addition to promoting the survival of neurons, lowering blood sugar, and anti-inflammation. This article reviews recent findings on the mechanisms by which IGF-1 mediates exercise-induced improvement in skeletal muscle atrophy, providing a theoretical basis for the prevention and treatment of this disease.
Insulin-Like Growth Factor I/physiology* ; Muscular Atrophy/therapy* ; Humans ; Exercise/physiology* ; Muscle, Skeletal ; Animals ; Insulin-Like Peptides

OBJECTIVE: To investigate the anti-inflammatory effect of rutaecarpine (RUT) on monosodium urate crystal (MSU)-induced murine peritonitis in mice and further explored the underlying mechanism of RUT in lipopolysaccharide (LPS)/MSU-induced gout model in vitro. METHODS: In MSU-induced mice, 36 male C57BL/6 mice were randomly divided into 6 groups of 8 mice each group, including the control group, model group, RUT low-, medium-, and high-doses groups, and prednisone acetate group. The mice in each group were orally administered the corresponding drugs or vehicle once a day for 7 consecutive days. The gout inflammation model was established by intraperitoneal injection of MSU to evaluate the anti-gout inflammatory effects of RUT. Then the proinflammatory cytokines were measured by enzyme-linked immunosorbent assay (ELISA) and the proportions of infiltrating neutrophils cytokines were detected by flow cytometry. In LPS/MSU-treated or untreated THP-1 macrophages, cell viability was observed by cell counting kit 8 and proinflammatory cytokines were measured by ELISA. The percentage of pyroptotic cells were detected by flow cytometry. Respectively, the mRNA and protein levels were measured by real-time quantitative polymerase chain reaction (qRT-PCR) and Western blot, the nuclear translocation of nuclear factor κB (NF-κB) p65 was observed by laser confocal imaging. Additionally, surface plasmon resonance (SPR) and molecular docking were applied to validate the binding ability of RUT components to tumor necrosis factor α (TNF-α) targets. RESULTS: RUT reduced the levels of infiltrating neutrophils and monocytes and decreased the levels of the proinflammatory cytokines interleukin 1β (IL-1β) and interleukin 6 (IL-6, all P<0.01). In vitro, RUT reduced the production of IL-1β, IL-6 and TNF-α. In addition, RT-PCR revealed the inhibitory effects of RUT on the mRNA levels of IL-1β, IL-6, cyclooxygenase-2 and TNF-α (P<0.05 or P<0.01). Mechanistically, RUT markedly reduced protein expressions of tumor necrosis factor receptor (TNFR), phospho-mitogen-activated protein kinase (p-MAPK), phospho-extracellular signal-regulated kinase, phospho-c-Jun N-terminal kinase, phospho-NF-κB, phospho-kinase α/β, NOD-like receptor thermal protein domain associated protein 3 (NLRPS), cleaved-cysteinyl aspartate specific proteinase-1 and cleaved-gasdermin D in macrophages (P<0.05 or P<0.01). Molecularly, SPR revealed that RUT bound to TNF-α with a calculated equilibrium dissociation constant of 31.7 µmol/L. Molecular docking further confirmed that RUT could interact directly with the TNF-α protein via hydrogen bonding, van der Waals interactions, and carbon-hydrogen bonding. CONCLUSION RUT alleviated MSU-induced peritonitis and inhibited the TNFR1-MAPK/NF-κB and NLRP3 inflammasome signaling pathway to attenuate gouty inflammation induced by LPS/MSU in THP-1 macrophages, suggesting that RUT could be a potential therapeutic candidate for gout.
Animals ; NF-kappa B/metabolism* ; Male ; Indole Alkaloids/therapeutic use* ; Signal Transduction/drug effects* ; Mice, Inbred C57BL ; Inflammation/complications* ; Uric Acid ; Quinazolines/therapeutic use* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Humans ; Gout/chemically induced* ; Inflammasomes/metabolism* ; Cytokines/metabolism* ; THP-1 Cells ; Mitogen-Activated Protein Kinases/metabolism* ; Mice ; Molecular Docking Simulation ; Lipopolysaccharides ; Quinazolinones

Schizophrenia (SZ) stands as a severe psychiatric disorder. This study applied diffusion tensor imaging (DTI) data in conjunction with graph neural networks to distinguish SZ patients from normal controls (NCs) and showcases the superior performance of a graph neural network integrating combined fractional anisotropy and fiber number brain network features, achieving an accuracy of 73.79% in distinguishing SZ patients from NCs. Beyond mere discrimination, our study delved deeper into the advantages of utilizing white matter brain network features for identifying SZ patients through interpretable model analysis and gene expression analysis. These analyses uncovered intricate interrelationships between brain imaging markers and genetic biomarkers, providing novel insights into the neuropathological basis of SZ. In summary, our findings underscore the potential of graph neural networks applied to multimodal DTI data for enhancing SZ detection through an integrated analysis of neuroimaging and genetic features.
Humans ; Schizophrenia/pathology* ; Diffusion Tensor Imaging/methods* ; Male ; Female ; Adult ; Brain/metabolism* ; Young Adult ; Middle Aged ; White Matter/pathology* ; Gene Expression ; Nerve Net/diagnostic imaging* ; Graph Neural Networks

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

Obesity has emerged as a critical global public health challenge,with an urgent need for effective prevention and control strategies.Traditional nutritional intervention approaches often overlook individual variability and dietary complexity,which limits their effectiveness in achieving precision-based prevention and control.In this context,nutritional intervention strategies are gradually shifting from population-based models to individualized precision nutrition models,which integrate and analyze multidimensional data to open new pathways for obesity prevention and control.The theoretical framework of precision nutrition is based on the recognition that individual heterogeneity in biological mechanisms underlies individual variations in nutritional needs.The research approaches in precision nutrition include genomics,epigenetics,metagenomics,metabolomics,and integrated multi-omics analyses.In terms of application,precision nutrition combines advanced external dietary exposure assessment tools—such as Internet-based dietary assessment systems and AI-driven image recognition—with omics-derived internal biomarkers to enable accurate quantification of dietary intake.Principles such as holistic dietary integrity,full coverage of dietary restrictions,optimized cooking methods,and chrononutrition are emphasized in intervention strategies.Future efforts in precision nutrition should focus on overcoming technical challenges,including thorough integration of multi-omics data and the development of intelligent decision-making systems.The goal is to move beyond generalized,"one-size-fits-all"model toward tailored,precision-based intervention.Precision nutrition will provide essential scientific and technological support for the Healthy China 2030 initiative and help usher in a new era of scientific and individualized obesity prevention and control.

Objective To investigate the effects of peripheral blood neutrophil infiltration on the polarization regulation of cerebral resident microglia under a permanent ischemic stroke model.Methods Fifty-eight C57BL/6 mice were divided into two groups.One group was sham group,and the other group of mice was subjected to permanent middle cerebral artery occlusion surgery.Mice were euthanized 48 hours,7 days,14 days,and 30 days after surgery for tissue collection.Western blotting was used to detect expression levels of M1 microglia markers CD 16,M2 microglia marker arginase 1(Arg1),inflammatory cytokine interleukin-1 β(IL-1β),and neutrophil marker myeloperoxidase(MPO)in brain tissue.Immunofluorescence histochemical staining was used to assess neutrophil infiltration and M2 microglial distribution around the infarct area in brain sections.In vitro,purified neutrophils were co-cultured with BV2 microglial cells.After lipopolysaccharide stimulation,the phagocytosis of neutrophils by BV2 cells was observed,and the expression levels of CD16 and Arg1 proteins in BV2 cells were detected.Results Western blotting showed that the levels of CD16(P＜0.05),IL-1β(P＜0.001),and MPO(P＜0.05)in brain tissue increased significantly 48 hours and 7 days after surgery,then decreased,with MPO expression returning to normal levels 30 days after surgery.Immunofluorescence showed a significant increase of MPO-positive cells around the infarct area of the mouse cerebral cortex 48 hours after surgery(P＜0.001),followed by a decrease(P＜0.05).The number of ionized calcium binding adapter molecule 1(Iba1)and MPO double-positive cells gradually increased after surgery,and reached their peak at 14 days(P＜0.05).Iba1 and Arg1 double-positive cells also increased significantly 7 days(P＜0.05)and 14 days(P＜0.01)after surgery.In vitro,co-culture experiments showed that after BV2 phagocytosing neutrophils,CD 16(P＜0.05)significantly decreased and Arg1 significantly upregulated(P＜0.05).Conclusion In a permanent ischemic stroke model,microglia transition from M1 to M2 type after phagocytosing neutrophils,and the injured brain area changes from pro-inflammatory state to anti-inflammatory state.

Objective To investigate the prevalence and risk factors of work-related musculoskeletal disorders (WMSDs) among construction workers. Methods A total of 5 783 workers were selected as participants from 12 construction companies in Guangdong Province, Guangxi Zhuang Autonomous Region and Zhejiang Province using a convenient sampling method. The revised Musculoskeletal Disorders Questionnaire was used to investigate the prevalence and influencing factors of WMSDs. Results The prevalence of WMSDs was 27.4% among the construction workers. The prevalence of WMSDs in shoulder, neck, waist/lower back and hand/wrist was 10.6%, 9.5%, 9.5% and 9.4% respectively, which was higher than that in other body parts. Bianry logistic regression analysis showed that the risk of WMSDs in construction workers with junior high school education and below was higher than that of high school/ college and above (P<0.05). The risk of WMSDs was higher in drinkers than that in non-drinkers (P<0.01). The worse the health status of construction workers, the higher the risk of WMSDs (P<0.01). The risk of WMSDs in those who exercised once or twice a month was lower than that in those who did not exercise (P<0.05). The risk of WMSDs was higher in construction workers with longer working hours in uncomfortable postures and greater back bending amplitude at work (all P<0.01). The risk of WMSDs in construction workers with hands holding above the shoulder was higher than that with hands below the shoulder (P<0.05). Construction workers who repeated the same work daily, involved in high-temperature work, often worked overtime, had insufficient rest time, and had a shortage of department personnel had a relatively high risk of WMSDs (all P<0.01). Conclusion The prevalence of WMSDs among the construction workers was relatively high, and the most common WMSDs occurred in shoulder, neck, waist/lower back and hand/wrist. Individual characteristic, work type, work posture and work organization are the influencing factors of WMSDs. Comprehensive measures, especially ergonomic measures based on personal and occupational characteristics should be taken to reduce the risk of WMSDs among construction workers.

Objective:To explore the application effects of a four-in-one blended teaching model integrating artificial intelligence, virtual reality, 3D printing, and case-based learning (CBL) in the clinical teaching of spinal tumors.Methods:We divided 89 students on training in the Department of Orthopedics of Peking University Third Hospital from September 2022 to August 2024 into control group ( n=47) and experimental group ( n=42). The control group adopted traditional teaching, and the experimental group adopted the four-in-one teaching model. At the end of clinical teaching, an artificial intelligence test and a questionnaire survey were administered to the students to evaluate the teaching effects. The two groups were compared using the independent samples t-test with the use of SPSS 27.0. Results:The experimental group was superior to the control group with significant improvements in the answer accuracy rate (66.67%, χ2=9.44, P=0.002), learning interest [(4.50±0.63), t=2.75, P=0.007], theoretical knowledge mastery [(4.64±0.69), t=7.74, P<0.001], clinical thinking [(4.48±0.71), t=9.08, P<0.001], practical skills [(4.13±0.89), t=2.69, P=0.009], scientific research innovation [(4.71±0.59), t=9.28, P<0.001], teacher-student interaction [(4.74±0.54), t=12.76, P<0.001], and classroom attention [(4.69±0.52), t=12.64, P<0.001]. At the same time, the students in the experimental group put forward numerous constructive feedback. Conclusions:The four-in-one blended teaching model combining artificial intelligence, virtual reality, 3D printing, and CBL can help undergraduate medical students better recognize and diagnose spinal tumors with a correct clinical thinking path, achieving good teaching effects.

Ferroptosis is a cell death pattern associated with the regulation of the Nrf2/GPX4 signaling pathway.Activating the Nrf2/GPX4 signaling pathway can regulate the expression of genes and proteins related to oxidative stress,alleviate stress damage,and inhibit cell ferroptosis.At present,research on the intervention of traditional Chinese medicine in ferroptosis has made certain progress.Through literature research,it can be found that some traditional Chinese medicine active monomers can activate the Nrf2/GPX4 signaling pathway to inhibit ferrop-tosis,play a protective role in tissues and organs,and have ther-apeutic potential in various diseases.Some traditional Chinese medicine active monomers exhibit characteristics of multi organ protective effects and bidirectional regulation.This article discus-ses the relevant research on the inhibition of ferroptosis by acti-vating the Nrf2/GPX4 signaling pathway with traditional Chinese medicine active monomers,and proposes suggestions to provide reference and ideas for further basic and applied research.