Objective To establish an in vitro enzymatic activity evaluation system for OTULIN （OTU domain DUB with linear linkage specificity）and provide an experimental basis for OTULIN inhibitor screening. Methods The linear ubiquitin substrate protein His-Ub-Ub-Flag was designed, expressed, and purified. Using OTULIN^80-352 as the target enzyme and PR619 as a positive control, the enzyme-to-substrate ratio and reaction time were optimized to establish an in vitro OTULIN activity evaluation system. Results The linear ubiquitin substrate protein His-Ub-Ub-Flag was successfully obtained. OTULIN activity was significantly inhibited by PR619, which confirmed the feasibility of the assay. The optimal enzyme-to-substrate ratio of OTULIN^80-352 to His-Ub-Ub-Flag was 1∶16, and the optimal reaction condition was incubation at 37℃ for 20 min. Conclusion An in vitro enzymatic activity evaluation system for OTULIN was successfully established, which could be used to evaluate the inhibitory effects of candidate compounds on OTULIN activity and provide technical support for subsequent screening of OTULIN small-molecule inhibitors.

Membrane protein degradation is a cutting-edge field in targeted protein degradation (TPD). Herein, we developed glypican-3 (GPC3)-mediated lysosome-targeting chimeras (GLTACs) as a novel strategy for the targeted degradation of tumor-specific membrane proteins. GLTACs utilize tumor-specific expression and endocytosis properties of GPC3 to degrade membrane proteins. By conjugating a GPC3-targeting peptide with the ligand of protein of interest (POI), GLTACs induce the formation of a ternary complex that is internalized into lysosomes, leading to the degradation of the POI. The effectiveness and specificity of GLTACs were validated by designing PD-L1, c-Met, and FGFR1 degraders. In particular, GLTAC WP0 potently degraded PD-L1 and induced T-cell-mediated tumor killing against HepG2 cells, highlighting the potential therapeutic applications. The development of GLTAC technology expands the scope of TPD strategies and opens new avenues for discovering novel therapeutic modalities against challenging protein targets.

OBJECTIVE To explore the mechanism by which Gongfa Static Training regulates mitophagy through the PTEN-in-duced kinase 1(PINK1)/Parkin pathway in skeletal muscle insulin resistance in type 2 diabetes mellitus(T2DM).METHODS T2DM mouse model was established using a high-fat diet combined with streptozotocin(STZ)intraperitoneal injection.Mice were ran-domly divided into a model group,a metformin group,an aerobic exercise group,and a Gongfa Static Training group.The intervention effects of Gongfa Static Training were evaluated by measuring fasting blood glucose,Homeostatic Model Assessment of Insulin Resist-ance(HOMA-IR),glycated hemoglobin(HbA1c),lipid metabolism indicators,mitochondrial function in the gastrocnemius muscle,and the expression of PINK1 and Parkin-related genes and proteins.RESULTS Gongfa Static Training significantly reduced fasting blood glucose,HbA1c,and insulin resistance index in T2DM mice,improved lipid metabolism,and enhanced insulin sensitivity.It improved the structure and function of mitochondria in the gastrocnemius muscle by upregulating the mRNA and protein expression of PINK1 and Parkin.CONCLUSION Gongfa Static Training improves mitochondrial function and insulin resistance in the skeletal muscle of T2DM mice by regulating the PINK1/Parkin pathway.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

OBJECTIVE To explore the mechanism by which Gongfa Static Training regulates mitophagy through the PTEN-in-duced kinase 1(PINK1)/Parkin pathway in skeletal muscle insulin resistance in type 2 diabetes mellitus(T2DM).METHODS T2DM mouse model was established using a high-fat diet combined with streptozotocin(STZ)intraperitoneal injection.Mice were ran-domly divided into a model group,a metformin group,an aerobic exercise group,and a Gongfa Static Training group.The intervention effects of Gongfa Static Training were evaluated by measuring fasting blood glucose,Homeostatic Model Assessment of Insulin Resist-ance(HOMA-IR),glycated hemoglobin(HbA1c),lipid metabolism indicators,mitochondrial function in the gastrocnemius muscle,and the expression of PINK1 and Parkin-related genes and proteins.RESULTS Gongfa Static Training significantly reduced fasting blood glucose,HbA1c,and insulin resistance index in T2DM mice,improved lipid metabolism,and enhanced insulin sensitivity.It improved the structure and function of mitochondria in the gastrocnemius muscle by upregulating the mRNA and protein expression of PINK1 and Parkin.CONCLUSION Gongfa Static Training improves mitochondrial function and insulin resistance in the skeletal muscle of T2DM mice by regulating the PINK1/Parkin pathway.

Objective To establish a high-precision and high-specificity quantitative nuclear magnetic resonance phosphorus spectrometry method(31P-qNMR)for detecting the phosphorus content in calcium hydrogen phosphate chewable tablets.Methods Hexamethyl phosphoramide was used as an internal standard,phosphorus spectrum data of calcium hydrogen phosphate chewable tablets solution was collected.The linear relationship of calcium hydrogen phosphate within the concentration range of 1.0 to 9.0 mg/ml was studied,and sample recovery rate and repeatability experiments were conducted.Results Calcium hydrogen phosphate and the internal standard demonstrated a good linear relationship within the concentration range of 1.0 to 9.0 mg/ml,with a regression equation A=0.004 3+0.183 6C.The recovery rates for low,medium,and high concentrations were 98.0%,98.1%,and 98.4%,respectively,with relative standard deviations(RSD)of 0.31%,0.68%,and 0.62%,respectively(n=9).The average content of calcium hydrogen phosphate in the chewable tablets was determined to be 98.1%.Conclusion This study successfully established a high-precision and highly specific method for quantifying the content of calcium hydrogen phosphate in chewable tablets,which did not require a self-reference substance,was simple in sample preparation,and had a fast detection speed.The method could provide a new technical support for the quality control of phosphorus-containing drugs.

Chronic refractory wound (CRW) is one of the most challengeable issues in clinic due to complex pathogenesis, long course of disease and poor prognosis. Experts need to conduct systematic summary for the diagnosis and treatment of CRW due to complex pathogenesis and poor prognosis, and standard guidelines for the diagnosis and treatment of CRW should be created. The Guideline forthe diagnosis and treatment of chronic refractory wounds in orthopedic trauma patients ( version 2023) was created by the expert group organized by the Chinese Association of Orthopedic Surgeons, Chinese Orthopedic Association, Chinese Society of Traumatology, and Trauma Orthopedics and Multiple Traumatology Group of Emergency Resuscitation Committee of Chinese Medical Doctor Association after the clinical problems were chosen based on demand-driven principles and principles of evidence-based medicine. The guideline systematically elaborated CRW from aspects of the epidemiology, diagnosis, treatment, postoperative management, complication prevention and comorbidity management, and rehabilitation and health education, and 9 recommendations were finally proposed to provide a reliable clinical reference for the diagnosis and treatment of CRW.