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.

ObjectiveBased on the regulation of macrophage M2 polarization， this study aims to explore the molecular mechanism and action targets of the Qijia Rougan prescription and its key effector ingredients in anti-fibrosis， thereby providing a basis and reference for the development of new drugs for hepatic fibrosis. MethodsA rat model of hepatic fibrosis was established by subcutaneous injection of 40%CCl₄， followed by oral administration of Qijia Rougan granules. The volume of collagen fibers was detected using Masson staining， the fibrosis markers Collagen Ⅰ and α-SMA were detected using immunohistochemistry， the proportion of M2 macrophages was detected by flow cytometry. The expression levels of M2 macrophage phenotype markers CD163 and CD206 were detected using immunofluorescence double staining. Western blot was used to detect the levels of the transforming growth factor-β （TGF-β）， platelet derived growth factor subunit B （PDGFB）， interleukin-10 （IL-10）， phosphorylated Janus kinase 1 （p-JAK1）， and phosphorylated signal transducer and activator of transcription 6 （p-STAT6）. Real-time fluorescent quantitative PCR was used to detect the relative expression levels of JAK1， STAT6， Arginase 1（Arg1）， and Fizz1. Based on the theory of serum pharmacology， liquid chromatography-mass spectrometry and WENN analysis were used to obtain the active ingredients of Qijia Rougan prescription. Molecular docking and molecular dynamics simulation were performed to analyze the effector ingredients and their targets. The identified effector ingredients were interfered with IL-4-induced M2 polarization of RAW264.7 macrophage in vitro to validate the targets. ResultsQijia Rougan prescription significantly reduced the content of fibrosis markers α-SMA and Collagen Ⅰ， as well as collagen fiber content （P<0.05）. It decreased the proportion of M2 macrophages and the levels of related cytokines IL-10， TGF-β and PDGFB， and up-regulated the levels of p-JAK1 and p-STAT6 （P<0.05）. A total of 1 214 compounds were identified from Qijia Rougan prescription， medicated serum and blank serum， and 29 ingredients were finalized by Venn analysis， including 15 blood-entry prototypes and 14 drug metabolites. Molecular docking showed that enoxolone and berberine bound more strongly to JAK1， with binding free energies of -9.6 kcal·mol^-1（1 cal≈4.184 J） and -9.1 kcal·mol^-1， respectively. Molecular dynamics simulations showed that JAK1-enoxolone and JAK1-berberine exhibited stable simulation trajectories within 100 ns， with essentially identical conformations and high protein overlap before and after simulation. Their binding free energies were -25.18 5.0.81 kcal·mol^-1 and -27.39 7.0.85 kcal·mol^-1， respectively. The number of hydrogen bonds formed between JAK1 and enoxolone ranges from 0 to 5， and most of the time can be maintained at 2-3. In vitro intervention with enoxolone or berberine significantly reduced p-JAK1 and p-STAT6 levels （P<0.05）. ConclusionQijia Rougan prescription inhibits M2 macrophage polarization in hepatic fibrosis. Enoxolone and berberine are the key effector ingredients of Qijia Rougan prescription to inhibit macrophage M2 polarization through targeting JAK1 and modulating the JAK1/STAT6 signaling pathway， thereby ameliorating hepatic fibrosis. This study provides a basis for prescription optimization， clinical application and new drug development， as well as a reference for monolithic anti-hepatic fibrosis research.

Objective To investigate the effects and potential mechanisms of polystyrene micro/nanoplastics(PS-MNPs)on testicular Sertoli cells.Methods Sixty male C57BL/6N mice(8 weeks old)were randomly divided into a control group(deionized water),a PS-NPs group[particle size of 20 nm,2.5 mg/(kg·d)],and a PS-MPs group[particle size of 5 μm,2.5 mg/(kg·d)],with 20 mice in each group.The corresponding agents were gavaged once daily for 6 months.HE staining was used to observe the histopathological and morphological changes in the testicular tissues.Immunohistochemistry of marker proteins was employed to evaluate the changes in the number of Sertoli cells.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses were performed to identify functions and signaling pathways enriched in the testicular transcriptome.Mouse testicular Sertoli cell line TM4 was divided into a control group(deionized water),a 2.5NPs group(2.5 μg/mL),and a 2.5MPs group(2.5 μg/mL).All groups received continuous exposure through 130 cell passages.Cell viability and proliferative capacity were evaluated using CCK-8 assay and EdU incorporation,while cell migration was assessed using transwell and cell scratch assays.RT-qPCR and Western blotting were used to detect the changes in the expression of key molecules regulating mesenchymal phenotypic transformation(MPT)at mRNA and protein levels.Results Pathological analysis revealed that,when compared to the control group,PS-NPs and PS-MPs treatment resulted in extended spaces between testicular seminiferous tubules,loosely arranged spermatogenic cells,and enhanced vacuolization.Immunohistochemical analysis of marker proteins indicated a decreasing trend in the number of testicular Sertoli cells in the PS-NPs and PS-MPs groups than the control group,with the PS-NPs group having statistical significance(P<0.01).GO and KEGG enrichment analyses revealed that PS-MNPs exposure-related altered genes were significantly enriched in cell adhesion signaling pathways(P<0.05).PS-MPs exposure significantly inhibited the growth and migration ability of TM4 cells(P<0.05),but PS-NPs exposure had no such effect on cell growth but notably enhanced cell migration ability.PS-NPs exposure inhibited the expression levels of E-cadherin and ZO-1(P<0.01)and up-regulated the expression of N-cadherin and vimentin(P<0.01),and PS-MPs exposure led to significant up-regulation of vimentin(P<0.01)and down-regulation of E-cadherin,N-cadherin,and ZO-1(P<0.05).Both PS-MPs and PS-NPs exposure up-regulated the mRNA levels of Snail2,Twist1,and Zeb2(P<0.01).Conclusion Exposure of PS-MNPs leads to abnormal proliferation and migration of TM4 cells,induces decreases in cell-cell contacts among Sertoli cells and spermatogenic cells at all levels possibly through MPT,and thus results in testicular damage.

Objective To investigate whether long-term low-dose exposure to polystyrene microplastics(PS-MPs)induces ferroptosis in testicular Sertoli cells and then leads to testicular injury.Methods Forty 8-week-old male C57BL/6 mice were randomly divided into a control group(deionized water group)and a PS-MPs group[2.5 mg/(kg·d)],with 20 mice in each group.Corresponding agents were gavaged once a day for 12 consecutive months.HE staining and Prussian blue staining were used to detect histopathological damage and accumulation of ferrous ions in the testes.Electron transmission microscopy was employed to observe the mitochondrial morphology of testicular Sertoli cells.Mouse Sertoli cell line TM4 was divided into a Con group(standard culture)and an MPs group(2.5 μg/mL PS-MPs).After both groups underwent continuous exposure and passed up to the 100th generation,morphological changes were observed under the microscope;cell viability was detected with CCK8 assay,and production of reactive oxygen species(ROS)and mitochondrial membrane potential(MMP)were detected with a ROS probe and a mitochondrial membrane potential probe(JC-1),respectively.Flow cytometry,ferrous ion(Fe2+)kit and Western blotting were applied to detect cell apoptosis,intracellular iron ion content,and protein levels of key molecules of ferroptosis in tissues and cells.Results Long-term exposure to PS-MPs resulted in significantly reduced diameter and thickness of mouse varicocele(P<0.01),fewer testicular Sertoli cells(P<0.05),with characteristic ferroptosis alterations in the mitochondria,and increased accumulation of ferrous ions in testicular tissue.Exposure to PS-MPs down-regulated the key molecules of ferroptosis,glutathione peroxidase 4(GPX4)and ferritin light chain(FTL)when compared with the control group(P<0.05).In the cell model,long-term PS-MPs exposure led to morphological changes and decreased cell viability(P<0.05),more production of ROS(P<0.01),and decrease in MMP(P<0.05)of TM4 cells.The exposure had no effect on cell apoptosis,but elevated the intracellular content of ferric ions(P<0.01),and down-regulated GPX4 and FTL protein levels(P<0.05).Conclusion Long-term low-dose exposure to PS-MPs induces mitochondrial damage and oxidative stress in testicular Sertoli cells,activates the ferroptosis pathway,and ultimately leads to testicular injury in mice.

Objective To determine the median effective concentration(EC50)of ropivacaine at the volume of 0.5 mL/kg for ultrasound-guided interscalene brachial plexus block in children aged 6 to 10 years.Methods A prospective dose-finding trial was conducted based a sequential Dixon up-and-down allocation.We recruited children aged 6 to 10 years who were scheduled for unilateral surgery on upper extremity regions in our hospital from April to December 2022.All of them were subjected to general intravenous anaesthesia combined with ultrasound-guided interscalene brachial plexus block.The ropivacaine volume for each patient was 0.5 mL/kg.The concentration of 0.2%for the first patient,subsequent concentrations were adjusted based on the block effect of previous patient,increase or decrease by 0.02%.The trial was stopped when there were 7 turning points.Isotonic regression and Bootstrap were used to calculate the values of EC50 and 95%effective concentration(EC95),along with their 95%confidence intervals(CI).General data,incidence of adverse events,and score of postoperative pain were recorded.Results A total of 26 children aged 6 to 10 years were included.The EC50 of ultrasound-guided interscalene brachial plexus block was determined to be 0.091%(95%CI:0.077%～0.105%),and the EC95 was estimated to be 0.117%(95%CI:0.110%～0.118%).Successful blockade was achieved in 16 cases(61.5%),while 10 cases(38.5%)failed.No statistical differences existed between successful and failed cases regarding sex,age,body weight,surgical site,surgical laterality,operative time,or anesthesia duration.None of the patients experienced adverse events such as pneumothorax,vascular injury,or Horner's syndrome,and the score of postoperative pain were all<6 by modified Children's Hospital of Eastern Ontario Pain Scale.Conclusion In children aged 6 to 10 years,the EC50 of ropivacaine is 0.091%at a volume of 0.5 mL/kg for ultrasound-guided interscalene brachial plexus block,and this low dose of regional anesthetic can reduce the risks such as systemic toxicity and direct neurotoxicity.

Metal-organic frameworks(MOFs)are porous materials composed of metal ions or metal clusters and organic ligands by coordination,which have the advantages of large specific surface area,good thermal stability and adjustable pore size,and have a promising application in gas chromatographic separation.In recent years,MOFs materials have been used as stationary phases for gas chromatography mainly including ZIF,MIL,UiO-66,HKUST-1,IRMOFs,etc.Based on the molecular sieve effect,van der Waals forces,hydrogen bonding and π-π interactions,the pore size,pore microenvironment,unsaturated metal site and special functional group of the MOFs stationary phase materials can be specifically designed and regulated.MOFs materials as stationary phases have unique separation performance for n-alkanes and their isomers,aromatic compounds and their isomers,alcohols/ketones/aldehydes and their isomers,and chiral compounds.The combination of organic polymers and novel nanomaterials with MOFs materials can improve the separation performance and stability of MOFs.Therefore,MOFs materials are expected to be the promising stationary phase that can be applied to gas separation in complex environments.In this article,the research advances of various stationary phases based on MOFs for gas chromatography in recent years were reviewed.The separation performance and separation mechanism of MOFs stationary phases for mixed gas samples were discussed,and the development trends in the future were prospected.

In this study,an ON/OFF type micro-valve with a sandwich(glass-silicon-glass)structure was designed and fabricated based on the micro-electro-mechanical system(MEMS)technique.The deformable membrane of this micro-valve was prepared on the silicon on insulator(SOI)substrate and sealed using Si-Si bonding and anodic bonding methods.The micro-valve had high-temperature stability and was suitable for integration with other gas chromatography components.The deformable membrane with a thickness of 10 μm was processed on the top silicon of the SOI substrate.The flow control of the micro-valve could be achieved by changing the driving pressure applied to the deformable membrane to deform it.Compared with polymer membranes,the deformable membrane prepared on the top layer silicon of SOI had better temperature stability and could be released using the deep reactive ion etching technique after silicon-silicon bonding,avoiding deformation during the preparation process.In addition,due to the small gap between the membrane and the inlet/outlet holes,the dead volume of the microvalve was very small.The test results indicated that the micro-valve achieved flow control and ON/OFF functions with good repeatability.

A pyrene-phenol-based fluorescent probe PyP which showed typical intramolecular charge transfer(ICT)and monomer-excimer activities was synthesized by using pyrene carboxaldehyde hydrazone and 4-tert-butyl-2,6-diformylphenol as the raw materials.The effects of solvents on PyP were studied,and the results showed that the color of protic polar solvents(Ethanol,N,N-dimethylformamide,methanol and H2O)were successfully identified.Based on the solvent polarity-regulated PyP monomer-excimer switching,the rapid and highly sensitive ratiometric probe,"Turn-off"and"Turn-on"multimodal probes were established for detection of trace water content in organic solvents(Dimethyl sulfoxide,N,N-dimethylformamide,ethanol and methanol),with detection limits(3σ/k)of 0.0021％,0.046％,0.062％and 0.024％.The method was successfully used to detect water content in dimethyl sulfoxide,N,N-dimethy lformamide,ethanol and methanol commercial organic solvents,with recoveries ranging from 97.2％to 108.0％.The developed method showed good accuracy and stability,and had good application prospect.

A monolithic integrated gas chromatography chip,consisting of a micro gas chromatography column(μGCC)and a micro helium discharge ionization detector(μHDID)was proposed.The chip was fabricated using micro electromechanical system(MEMS)technique,and its sensitivity was improved from two aspects.On one hand,open tubular column was selected as the separation device,and the auxiliary helium channel width of μHDID was modulated based on the microchannel width of the μGCC to match the flow rates of μHDID and μGCC.On the other hand,the electrode structure inside the μHDID collection zone was optimized,a bias electrode group around the collection electrode was constructed,and the ion collection efficiency was improved.After coating HKUST-1 as the stationary phase,the monolithic integrated gas chromatography chip could achieve baseline separation and detection of light hydrocarbon gas mixture(methane,ethane,propane,andn-butane),with a detection limit for propane as low as 25 pg.The chip could carried out test under temperature-programmed conditions,with a resolution of 9.24 for ethane and propane.

A micro gas chromatographic column with mesoporous surface micro column array prepared by anodization method was proposed.A porous support layer with a characteristic pore size of about 30 nm inside the chromatographic column was prepared in situ using anodization method,and a uniform alumina stationary phase was deposited on the mesoporous support layer using atom layer deposition(ALD)technique.The existence of a mesoporous support layer increased surface area of the chromatographic column,thereby increasing the total amount of stationary phase loading and enhancing column capacity,which facilitated chromatographic separation.The test results showed that the porous support layer significantly reduced the longitudinal molecular diffusion and mass transfer resistance of the micro gas chromatographic column,and significantly increased the number of theoretical plates(n-nonane increased by 290.2%).Furthermore,column efficiency of the chromatographic column was less affected by flow rate,which was conducive to rapid separation of heavy hydrocarbon mixtures.