Osteoarthritis (OA), a highly prevalent degenerative joint disease worldwide, is defined by articular cartilage degradation, abnormal bone remodeling, and persistent chronic inflammation. It severely compromises patients’ quality of life, and currently, there is no radical cure. Abnormal mechanical stress is widely regarded as a core driver of OA pathogenesis, and the exploration of mechanical signal perception and transduction mechanisms has become crucial for deciphering OA’s pathophysiological processes. Piezo1, a key mechanosensitive cation channel belonging to the Piezo protein family, has recently gained significant attention due to its pivotal role in mediating cellular responses to mechanical stimuli in joint tissues. This review systematically examines Piezo1’s expression patterns, regulatory mechanisms, and pathological functions in OA, with a particular focus on its dual roles in modulating chondrocyte homeostasis and bone metabolism disorders, while also delving into the underlying molecular signaling pathways and potential therapeutic implications. Piezo1, consisting of approximately 2 500 amino acids and forming a unique trimeric propeller-like structure, is widely expressed in chondrocytes, osteocytes, mesenchymal stem cells, and synovial cells. It exhibits permeability to cations such as Ca²⁺, K⁺, and Na⁺, and directly responds to membrane tension changes induced by mechanical stimuli like fluid shear stress and mechanical overload. In OA patients and animal models, Piezo1 expression is significantly upregulated, especially in cartilage regions subjected to abnormal mechanical stress (e.g., human temporomandibular joint cartilage). This overexpression is closely associated with aggravated cartilage degeneration, increased chondrocyte apoptosis, accelerated cellular senescence, and intensified inflammatory responses. Mechanical overload and pro-inflammatory cytokines (e.g., IL-1β) are key inducers of Piezo1 upregulation: IL-1β activates the PI3K/AKT/mTOR signaling pathway to enhance Piezo1 expression, forming a pathogenic positive feedback loop that inhibits chondrocyte autophagy, promotes apoptosis, and further accelerates joint degeneration. Mechanistically, Piezo1 mediates OA progression through multiple interconnected pathways. When activated by mechanical stress, Piezo1 triggers excessive Ca²⁺ influx, leading to endoplasmic reticulum stress (ERS) and mitochondrial dysfunction, which directly induce chondrocyte apoptosis. This process involves the activation of downstream signaling cascades such as cGAS-STING and YAP-MMP13/ADAMTS5. YAP, a transcriptional regulator, upregulates the expression of matrix metalloproteinase 13 (MMP13) and aggrecanase (ADAMTS5), thereby accelerating cartilage matrix degradation. Additionally, Piezo1-driven Ca²⁺ overload promotes the accumulation of reactive oxygen species (ROS) and upregulates senescence markers (p16 and p21), accelerating chondrocyte senescence via the p38MAPK and NF-κB pathways. Senescent chondrocytes secrete senescence-associated secretory phenotype (SASP) factors (e.g., IL-6, IL-1β), further amplifying joint inflammation. In terms of bone metabolism, Piezo1 maintains joint homeostasis by promoting the differentiation of fibrocartilage stem cells into chondrocytes and balancing bone formation and resorption through regulating the FoxC1/YAP axis and RANKL/OPG ratio. Therapeutically, targeting Piezo1 shows promising potential. Preclinical studies have demonstrated that Piezo1 inhibitors (e.g., GsMTx4) can reduce joint damage and alleviate pain in OA mice. Simultaneously, siRNA-mediated co-silencing of Piezo1 and TRPV4 (another mechanosensitive channel) decreases intracellular Ca²⁺ concentration, inhibits chondrocyte apoptosis, and promotes cartilage repair. Conditional knockout of Piezo1 using Gdf5-Cre transgenic mice alleviates cartilage degeneration in post-traumatic OA models by downregulating MMP13 and ADAMTS5 expression. Despite existing challenges, such as off-target effects of inhibitors, inefficient local drug delivery, and interindividual genetic variability, strategies like developing selective Piezo1 antagonists, optimizing targeted nanocarriers, and combining Piezo1-targeted therapy with physical therapy provide viable avenues for clinical translation. The authors propose that Piezo1 serves as a critical therapeutic target for OA, and future research should focus on deciphering its context-dependent regulatory networks, developing tissue-specific intervention strategies, and validating their efficacy and safety in clinical trials to address the unmet medical needs of OA patients.

Creutzfeldt-Jakob disease(CJD)is a rapidly progressive and fatal neurodegenerative disorder caused by prions,with certain infectivity and iatrogenic transmission risks.With the rapid progress and application of new dia-gnostic biomarkers and detection methods,as well as the construction and improvement of surveillance and reporting systems,the detection of CJD in patients domestically and internationally has shown an increasing trend year by year.Due to its long incubation period and heterogeneity of early symptoms,early identification and diagnosis of the disease is difficult,increasing the risk of transmission within medical institutions.Currently,there is a lack of con-sensus on the infection prevention and control of CJD.In order to timely identify and diagnose CJD as well as effec-tively block its transmission in medical institutions,this consensus summarizes 15 clinical concerns and formulates 24 specific recommendations based on the latest domestic and international research findings and clinical evidence,as well as combines with clinical practice,aiming to standardize healthcare-associated infection prevention and control measures for CJD and reduce its transmission risk in medical institutions.

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.

BACKGROUND: Hypertension is associated with an increased risk of calcific aortic valve stenosis (CAVS). However, the directionality of causation between blood pressure traits and aortic stenosis is unclear, as is the benefit of antihypertensive drugs for CAVS. METHODS: Using genome-wide association studies (GWAS) summary statistics, we performed bidirectional two-sample univariable mendelian randomization (UVMR) to assess the causal associations of systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure (PP) with CAVS. Multivariable mendelian randomization (MVMR) was conducted to evaluate the direct effect of hypertension on CAVS, adjusting for confounders. Drug target mendelian randomization (MR) and summary-level MR (SMR) were used to estimate the effects of 12 classes of antihypertensive drugs and their target genes on CAVS risk. Inverse variance weighting was the primary MR method, with sensitivity analyses to validate results. RESULTS: UVMR showed SBP, DBP, and PP have causal effects on CAVS, with no significant reverse causality. MVMR confirmed the causality between hypertension and CAVS after adjusting for confounders. Drug-target MR analyses indicated that calcium channel blockers (CCBs), loop diuretics, and thiazide diuretics via SBP lowering exerted protective effects on CAVS risk. SMR analysis showed that the CCBs target gene CACNA2D2 and ARBs target gene AGTR1 were positively associated with CAVS risk, while diuretics target genes SLC12A5 and SLC12A1 were negatively associated with aortic stenosis risk. CONCLUSIONS Hypertension has a causal relationship with CAVS. Managing SBP in hypertensive patients with CCBs may prevent CAVS. ARBs might exert protective effects on CAVS independent of blood pressure reduction. The relationship between diuretics and CAVS is complex, with opposite effects through different mechanisms.

AIM:To investigate the effects of high-dose methotrexate(MTX)on alkaline phosphatase(ALP)and the effects of ALP changes on bone me-tabolism,bone marrow granulogram function,liver function and excretion.METHODS:Aspartate ami-notransferase(AST),alanine aminotransferase(ALT)and albumin(ALB)were used as liver function indi-cators,serum calcium(Ca)and phosphorus(P)were used as bone metabolism indicators,neutro-phil(ANC)and white blood cell count(WBC)were used as bone marrow granuloline function indica-tors,and methotrexate C48h concentration ≥1 μmol/L was used as the excretion delay.One-way ANOVA analysis was performed on the ALP levels before and after the first chemotherapy and the second chemotherapy,and the children were divided into normal group and low group according to the ALP level,and the seven indexes before and after che-motherapy were quantitatively and qualitatively an-alyzed,and univariate and multivariate Logistic re-gression analysis was performed on the concentra-tion of methotrexate C48h and the above indexes in the children treated with the second chemothera-py.RESULTS:After the first chemotherapy and the second chemotherapy,ALP was significantly de-creased[(204.0±83.6)U/L vs.(172.8±67.3)U/L,(179.4±59.3)U/L vs.(169.6±57.1)U/L,all P＜0.05],and the serum Ca,P,ANC,WBC,and ALB were sig-nificantly decreased(P＜0.05),and AST and ALT were increased(P＜0.05),and ALT was an indepen-dent risk factor for delayed excretion(OR=1.049,95％CI 1.023-1.077,P＜0.001),ALB was an indepen-dent protective factor for delayed excretion(OR=0.551,95％CI 0.460-0.660,P＜0.001),and ALP was not a significant contributor to MTX excretion de-lay.CONCLUSION:ALP is not a good predictor of liv-er function and bone marrow granulopathy func-tion due to a significant decrease in ALP caused by high-dose MTX,and ALP together with serum calci-um and phosphorus levels can constitute an early warning indicator of bone metabolism disorders.

Creutzfeldt-Jakob disease(CJD)is a rapidly progressive and fatal neurodegenerative disorder caused by prions,with certain infectivity and iatrogenic transmission risks.With the rapid progress and application of new dia-gnostic biomarkers and detection methods,as well as the construction and improvement of surveillance and reporting systems,the detection of CJD in patients domestically and internationally has shown an increasing trend year by year.Due to its long incubation period and heterogeneity of early symptoms,early identification and diagnosis of the disease is difficult,increasing the risk of transmission within medical institutions.Currently,there is a lack of con-sensus on the infection prevention and control of CJD.In order to timely identify and diagnose CJD as well as effec-tively block its transmission in medical institutions,this consensus summarizes 15 clinical concerns and formulates 24 specific recommendations based on the latest domestic and international research findings and clinical evidence,as well as combines with clinical practice,aiming to standardize healthcare-associated infection prevention and control measures for CJD and reduce its transmission risk in medical institutions.

AIM:To investigate the effects of high-dose methotrexate(MTX)on alkaline phosphatase(ALP)and the effects of ALP changes on bone me-tabolism,bone marrow granulogram function,liver function and excretion.METHODS:Aspartate ami-notransferase(AST),alanine aminotransferase(ALT)and albumin(ALB)were used as liver function indi-cators,serum calcium(Ca)and phosphorus(P)were used as bone metabolism indicators,neutro-phil(ANC)and white blood cell count(WBC)were used as bone marrow granuloline function indica-tors,and methotrexate C48h concentration ≥1 μmol/L was used as the excretion delay.One-way ANOVA analysis was performed on the ALP levels before and after the first chemotherapy and the second chemotherapy,and the children were divided into normal group and low group according to the ALP level,and the seven indexes before and after che-motherapy were quantitatively and qualitatively an-alyzed,and univariate and multivariate Logistic re-gression analysis was performed on the concentra-tion of methotrexate C48h and the above indexes in the children treated with the second chemothera-py.RESULTS:After the first chemotherapy and the second chemotherapy,ALP was significantly de-creased[(204.0±83.6)U/L vs.(172.8±67.3)U/L,(179.4±59.3)U/L vs.(169.6±57.1)U/L,all P＜0.05],and the serum Ca,P,ANC,WBC,and ALB were sig-nificantly decreased(P＜0.05),and AST and ALT were increased(P＜0.05),and ALT was an indepen-dent risk factor for delayed excretion(OR=1.049,95％CI 1.023-1.077,P＜0.001),ALB was an indepen-dent protective factor for delayed excretion(OR=0.551,95％CI 0.460-0.660,P＜0.001),and ALP was not a significant contributor to MTX excretion de-lay.CONCLUSION:ALP is not a good predictor of liv-er function and bone marrow granulopathy func-tion due to a significant decrease in ALP caused by high-dose MTX,and ALP together with serum calci-um and phosphorus levels can constitute an early warning indicator of bone metabolism disorders.

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 discuss the application effect of using a stone extractor balloon catheter to assist in crossing the anastomotic stenosis in treatment of anastomotic biliary stenosis after liver transplantation using endoscopic retrograde cholangiopancreatography(ERCP).Methods Clinical data of 48 patients who developed anastomotic biliary stenosis after liver transplantation and underwent ERCP treatment were collected.Upon unsuccessful use of a dilation catheter to cross the stricture,attempts were made to cross the anastomotic biliary stenosis by using a stone extractor balloon catheter.The success rate of the procedure was recorded,intraoperative conditions were observed,treatment outcomes and complications were analyzed.Results The main presenting symptoms in the 48 patients on admission were abdominal discomfort(32 patients),fever(7 patients),pruritus(4 patients),jaundice(3 patients),and no obvious symptoms(2 patients).Preoperative magnetic resonance cholangiopancreatography(MRCP)examination revealed isolated stricture of the anastomotic site in 35 cases,and stricture associated with stones in 13 cases.Using the stone extractor balloon catheter as a guide,guidewire crossing of the anastomotic stenosis was successful in 26 cases,resulting in a success rate of 54.17%(26/48).Through statistical analysis of the successful group and the failed group,there was a significant difference in whether the distal biliary dilatation between the two groups,and the difference was statistically significant(χ2 = 8.39,P = 0.004).In the 26 successfully treated cases,alanine transaminase(ALT),aspartate transaminase(AST),γ-glutamyl transpeptidase(γ-GT),alkaline phosphatase(ALP),and total bilirubin(TBiL)levels decreased significantly 48 hours after the procedure(P<0.05),and no serious complications occurred.Conclusion The use of a stone extractor balloon catheter significantly increases the success rate of crossing anastomotic stenosis in the treatment of anastomotic biliary stenosis after liver transplantation,especially in cases with distal dilatation of the common bile duct.This approach is safe and worth promoting.

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.