Piezo1 is a Ca²⁺-permeable mechanosensitive ion channel that plays a central role in mechanosensing and signal transduction in dental and periodontal tissues. In tooth tissue, Piezo1 is a key factor mediating dentin sensitive pain. The flow of dentinal tubule fluid induced by external stimulation can activate the Piezo1 channel on odontoblasts, triggering neuronal signals through the pannexin-1-purinergic 2X3 receptor (PANX-1-P2X3) receptor axis, resulting in pain perception. In addition, Piezo1 has a dual regulatory role in the process of pulp inflammation and repair : on the one hand, its expression is up-regulated in an inflammatory environment, which may aggravate pain sensitivity ; on the other hand, it activates the migration, proliferation and odontogenic differentiation of dental pulp stem cells by mediating Ca²⁺influx, ATP release and downstream purinergic 2X7 receptor (P2X7R), MEK / ERK signaling pathways, thereby promoting reparative dentin formation. In periodontal tissue, Piezo1 plays a central role in maintaining periodontal tissue homeostasis and regulating alveolar bone remodeling by sensing mechanical stimuli such as bite force. During orthodontic tooth movement, Piezo1 promotes osteogenic differentiation by activating Wnt / Ca²⁺, Notch and other pathways on the tension side. It affects osteoclast activity by regulating receptor activator of nuclear factor-κB ligand/osteoprotegerin (RANKL/OPG) balance on the pressure side. At the same time, Piezo1 is also a key regulator of periodontal immune microenvironment. It is expressed in immune cells such as macrophages, neutrophils and dendritic cells. Its activation can promote the polarization of macrophages to pro-inflammatory M1 type, enhance the release of pro-inflammatory factors and matrix metalloproteinases, and thus aggravate the inflammatory destruction of periodontal tissue.In view of its multiple functions, Piezo1 has become a potential therapeutic target, including local or systemic application of its inhibitors, mechanical intervention, physical therapy, gene therapy and stem cell therapy, showing a broad clinical transformation prospect in the treatment of oral diseases. In this paper, the structural characteristics, signal transduction mechanism of Piezo1 and its expression distribution, function and regulatory network in tooth tissue and periodontal tissue are reviewed, so as to provide ideas for the development of oral disease treatment strategies targeting Piezo1.

Objective To explore the predictive role of pathological risk score of gastric cancer (PRS_GC) in the prognosis of gastric cancer patients, and to further investigate the correlation between PRS_GC and tumor biological behavior. Methods Clinicopathological data were retrospectively collected from 1 120 patients with gastric cancer who underwent surgical resection at Zhongshan Hospital, Fudan University, between April 2006 and November 2019. PRS_GC was calculated using the previously established DeepRisk model, and patients were divided into high and low PRS_GC groups (560 patients per group) based on the median PRS_GC value. The proportions and spatial distances of immune cell subsets in gastric cancer tissues were assessed between the two groups. Data from stomach adenocarcinoma samples in The Cancer Genome Atlas was integrated to analyze PRS_GC-associated genetic mutations and signaling pathways. Results The survival rate of the high PRS_GC group was lower than that of the low PRS_GC group, and the recurrence rate was higher than that of the low PRS_GC group (P<0.000 1). Compared with the low-PRS_GC group, the high-PRS_GC group exhibited increased infiltration of regulatory T cells (Tregs) and neutrophils within the tumor region (P＜0.05), while the infiltration levels of natural killer T cells and cytotoxic T cells were markedly decreased (P＜0.05). Spatial analysis revealed that a shortened spatial distance between CD4⁺ T cells and Tregs was closely associated with poor prognosis in the high-PRS_GC group (P＝0.03). Furthermore, in the high-PRS_GC group, the number of TIM3⁺ cells showed a positive correlation with the infiltration levels of Tregs (r＝0.69, P＝0.01), CD8⁺ T cells (r＝0.61, P＝0.04), and CD4⁺ T cells (r＝0.67, P＝0.02). Gene set enrichment analysis indicated that a high PRS_GC was associated with the activation of pathways related to actin cytoskeleton regulation, the cGMP-PKG pathway, the Hippo pathway, and tumor proteoglycans. Conclusion A high PRS_GC is associated with an immunosuppressive tumor microenvironment, as well as tumor invasion and metastasis. It effectively predicts the prognosis of patients with gastric cancer and, by doing so, provides a potential theoretical basis for developing individualized strategies that combine targeted therapy with immunotherapy.

Objective To explore the impact of tumor-associated myeloid cell infiltration signatures on postoperative overall survival (OS) in patients with gastric cancer. Methods A retrospective analysis was performed on patients who underwent radical gastrectomy at Zhongshan Hospital, Fudan University from January 2005 to December 2019. Patients were randomly divided into a training set (n＝167) and an internal validation set (n＝168) at a 1:1 ratio. Meanwhile, 147 patients with gastric cancer treated at Zhongshan Hospital (Xiamen), Fudan University during the same period were enrolled as the external validation set (n＝147). Immunohistochemistry was used in all patients to evaluate the distribution characteristics of 18 immune markers in three regions of gastric cancer tissues, namely primary tumor (PT), invasive margin (IM), and normal tissue (NT). These markers include 11 myeloid cell markers (CD11b, CD33, CD11c, CD14, CD15, CD16, CD68, CD86, CD163, CD206, and CD66b) and 7 immune checkpoints (CD73, IDO, LAG3, PD-1, SIGLEC9, SIRPA, and TIM3). LASSO regression and Cox proportional hazards model were applied to screen immune markers associated with postoperative OS in gastric cancer patients, and a predictive model for 1-, 3-, and 5-year postoperative OS was established. Data from the internal and external validation set were used for internal and external verification of the predictive model. Receiver operating characteristic (ROC) curves were plotted and the area under the curve (AUC) was calculated to assess the discriminative ability of the model. Results In the training set, LASSO regression and Cox proportional hazards model identified 4 immune marker signatures (CD14_PT, CD15_PT, CD206_PT, and SIGLEC9_PT) to construct the predictive model. ROC curve analysis showed that the AUCs of the model for predicting 1-, 3-, and 5-year postoperative OS were 0.74, 0.75, and 0.84, respectively. When the model was applied to the internal and external validation sets, the AUCs for 1-, 3-, and 5-year postoperative OS were 0.74, 0.72, 0.72 (internal validation set) and 0.72, 0.71, 0.74 (external validation set), respectively. Cox multivariate regression analysis showed that the risk score was an independent risk factor for postoperative OS in patients with gastric cancer. Conclusion The model constructed based on LASSO-Cox regression exhibits good predictive performance and can effectively predict postoperative OS in gastric cancer patients, which may serve as a basis for intensive treatment of high-risk patients after surgery.

BACKGROUND:Macrophages are an important part of innate immunity.When the internal environment of the body changes,macrophages can produce different polarization phenotypes and play the corresponding inflammatory immune function.Mesenchymal stem cells can secrete a large number of extracellular vesicles into the internal environment of the body,which have the functions of intercellular signaling and immune regulation.Studies have shown that mesenchymal stem cells and mesenchymal stem cells-extracellular vesicles can affect the M1/M2 polarization balance of macrophages so as to treat immune inflammatory diseases.OBJECTIVE:To explore the signaling mechanism of how mesenchymal stem cells and their extracellular vesicles interfere with autoimmune diseases by regulating the polarization of macrophages,as well as the related research progress of engineered extracellular vesicles in this field.METHODS:The first author searched the relevant literature published in PubMed,CNKI and other databases until June 2024.Chinese search terms were"mesenchymal stem cells,extracellular vesicles,exosomes,apoptotic bodies,apoptotic vesicles,macrophage polarization,M1 polarization,M2 polarization,autoimmune diseases,multiple sclerosis,rheumatoid arthritis,systemic lupus erythematosus,type 1 diabetes mellitus,inflammatory bowel disease,autoimmune dacryadenitis,engineered extracellular vesicles,engineering exosomes,drug delivery."English search terms were"macrophage polarization,M1 macrophage,M2 macrophage,autoimmune disease,type 1 diabetes,multiple sclerosis,rheumatoid arthritis,systemic lupus erythematosus,autoimmune dacryadenitis,inflammatory bowel disease,mesenchymal stem cells,extracellular vesicles,engineered extracellular vesicles,engineering exosomes,drug delivery."The title and abstract of each paper were read and initially screened.Finally,70 articles were selected for induction and analysis.RESULTS AND CONCLUSION:(1)Mesenchymal stem cells can regulate M1/M2 polarization by releasing or indirectly acting on functional proteins.(2)Mesenchymal stem cells can regulate macrophage M2 polarization through inflammasome.(3)Mesenchymal stem cells can be combined with commonly used drugs to enhance drug efficacy.(4)Mesenchymal stem cells can regulate the release of mesenchymal stem cells-extracellular vesicles after inflammatory stimulation and affect the polarization of macrophages.(5)Mesenchymal stem cells-extracellular vesicles can regulate autoimmune diseases by targeting macrophage polarization through PTEN,NOTCH,nuclear factor κB,Toll-like receptors,PI3K/AKT and other pathways.(6)Engineered extracellular vesicles can achieve non-invasive targeted drug delivery,prolong the half-life of drugs,promote the oral administration of exosomes,reduce allograft reaction,improve the bioavailability of Chinese herbs and overcome the blood-brain barrier,opening up a new path for drug delivery.

Objective To investigate the clinical outcome differences between robotic-assisted intramedullary nailing and traditional manual surgery,and to analyze the advantages and feasibility of robotic-assisted intramedullary nail fixation in the treatment of intertrochanteric fractures in elderly patients.Methods From December 2023 to December 2024,elderly patients with intertrochanteric fractures who underwent surgery at Department of Trauma Orthopedics,Beijing Luhe Hospital,Capital Medical University were included.Patients were divided into two groups based on the surgical method.The robotic-assisted group underwent robotic-assisted intramedullary nail fixation,while the traditional group received manual intramedullary nail fixation.Baseline data and observation indicators were collected and compared between the two groups to assess any differences.Results There were no statistically significant differences in baseline data between the two groups(P>0.05).The intraoperative blood loss in the robotic-assisted group was(94.28±9.43)mL,compared to(143.00±11.11)mL in the traditional group(P<0.001).The operative time in the robotic-assisted group was(53.06±9.89)min,while in the traditional group,it was(66.74±10.18)min(P<0.001).The skin incision length for the main nail in the robotic-assisted group was(3.23±0.64)cm,whereas in the traditional group,it was(4.03±0.79)cm(P<0.01).Postoperative hemoglobin levels in the robotic-assisted group decreased by(12.63±4.27)g/L,compared to(17.29±4.32)g/L in the traditional group(P=0.018).At 6 months postoperatively,the Harris hip scores in the robotic-assisted group showed 30 cases of excellent,10 good,and 3 poor outcomes,while in the traditional group,there were 22 excellent,15 good,and 6 poor cases(P=0.198).Conclusion Robotic-assisted intramedullary nailing for intertrochanteric fractures offers advantages such as minimally invasive and precise procedures,shorter operative times,and reduced blood loss.Compared to traditional surgical methods,it demonstrates certain benefits in reducing postoperative complications in elderly patients.

Objective To explore the technical advantages and applicable scenarios of surgical robot-assisted versus conventional freehand minimally invasive surgery for pelvic fractures by comparing clinical indicators,thereby providing evidence for clinical decision-making.Methods A retrospective case-control study was conducted on 59 patients with pelvic fractures treated with minimally invasive internal fixation between January 2022 and December 2024.Patients were divided into a conventional group(26 cases)and a robot-assisted navigation group(33 cases)based on the surgical technique.Pre-and postoperative pelvic computed tomography(CT)scans were performed,and anteroposterior,outlet,and inlet view radiographs were obtained.The maximum residual displacement after pelvic reduction and screw placement accuracy were measured based on radiographic and CT imaging.Intraoperative fluoroscopy frequency,radiation dose,operative time,blood loss,number of implanted screws,maximum residual displacement after reduction,and screw accuracy were recorded.Results No significant differences were observed between the two groups in age,gender,injury mechanism,or fracture classification,indicating comparability.Blood loss and fracture reduction quality showed no significant differences.The operative time was 52.5(30.8,62.3)min in the conventional group and 60(50,82.5)min in the robot-assisted group.Intraoperative fluoroscopy frequency and radiation dose were(19.1±5.4)times and 33.1(27.5,43.9)mGy in the conventional group,compared to(12.1±4.9)times and 123.1(101.1,131.4)mGy in the robot-assisted group.The robot-assisted group demonstrated superior screw placement accuracy,increased utilization of anterior column screws,and shorter postoperative ambulation time.Conclusion Robot-assisted minimally invasive surgery for pelvic fractures significantly outperforms conventional freehand techniques in improving screw placement accuracy and reducing radiation exposure for surgeons.It represents a preferable option for treating unstable pelvic fractures.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP