BACKGROUND:Studies have shown that metformin has anti-inflammatory,anti-tumor,anti-aging and vasoprotective effects,and can inhibit the progression of osteoarthritis,but its specific mechanism of action remains unclear. OBJECTIVE:To investigate the mechanism of metformin on cartilage protection in a rat model of osteoarthritis. METHODS:Forty male Sprague-Dawley rats were randomly divided into four groups(n=10 per group):blank,control,sham-operated,and metformin groups.The blank group did not undergo any surgery.In the sham-operated group,the joint cavity was exposed.In the model group and the metformin group,the modified Hulth method was used to establish the osteoarthritis model.At 1 day after modeling,the rats in the metformin group were given 200 mg/kg/d metformin by gavage,and the model,blank,and sham-operated groups were given normal saline by gavage.Administration in each group was given for 4 weeks consecutively.Hematoxylin-eosin staining,toluidine blue staining,and safranin O-fast green staining were used to observe the morphological structure of rat knee joints.Immunohistochemical staining and western blot were used to detect the protein expression of SOX9,type Ⅱ collagen,a disintegrin and metalloproteinase with thrombospondin motifs 5(ADAMTS5),Beclin1,P62,phosphatidylinositol 3-kinase(PI3K),p-PI3K,protein kinase B(AKT),p-AKT,mammalian target of rapamycin(Mtor),and p-Mtor in rat cartilage tissue. RESULTS AND CONCLUSION:The results of hematoxylin-eosin,toluidine blue and safranin O-fast green staining showed smooth cartilage surface of the knee joints and normal histomorphology in the blank group and the sham-operated group,while in the model group,there was irregular cartilage surface of the knee joint and cartilage damage,with a decrease in the number of chondrocytes and the content of proteoglycans in the cartilage matrix.In the metformin group,there was a significant improvement in the damage to the structure of the cartilage in the knee joints of the rats,and the cartilage surface tended to be smooth,with an increase in the number of chondrocytes and the content of proteoglycans in the cartilage matrix.Immunohistochemistry staining and western blot results showed that compared with the control and sham-operated groups,the expression of SOX9,type Ⅱ collagen,and Beclin1 proteins in the cartilage tissue of rats in the model group was significantly decreased(P<0.05).Conversely,the expression of ADAMTS5,P62,as well as p-PI3K,p-AKT,and p-Mtor proteins was significantly increased(P<0.05).Furthermore,compared with the model group,the expression of SOX9,type Ⅱ collagen,and Beclin1 proteins in the cartilage tissue of rats in the metformin group was significantly increased(P<0.05),while the expression of ADAMTS5,P62,as well as p-PI3K,p-AKT,and p-Mtor proteins was significantly decreased(P<0.05).To conclude,Metformin can improve the autophagy activity of chondrocytes and reduce the degradation of cartilage matrix in osteoarthritis rats by inhibiting the activation of PI3K/AKT/Mtor signaling pathway,thus exerting a protective effect on articular cartilage.

Objective To propose a whole-life cycle management model for valvular heart disease (VHD), systematically elucidate its underlying logic and implementation pathways, and concurrently review and analyze its preliminary application outcomes. Methods Since 2020, West China Hospital of Sichuan University has established a management system encompassing "assessment-decision-intervention-follow-up", including: (1) a risk-stratified, tiered management pathway; (2) six core functions ("promotion, screening, prevention, diagnosis, treatment, and rehabilitation") coordinated by disease-specific managers; (3) an intelligent decision support information platform; and (4) a collaborative network of multidisciplinary teams and regional academic alliances. To evaluate the effectiveness of this management model, we retrospectively included three cohorts: (1) the population screened by echocardiography from 2020 to 2024, analyzing the detection rate of aortic valve disease and risk stratification; (2) patients enrolled in the whole-life cycle management from April 2021 to December 2024, assessing follow-up outcomes, hospital satisfaction, and changes in quality of life; (3) patients who underwent transcatheter aortic valve replacement (TAVR) from January 2022 to January 2024, evaluating the one-year all-cause mortality rate, perioperative complications, and improvements in New York Heart Association (NYHA) classification. Results Between 2020 and 2024, a total of 583 874 individuals underwent echocardiographic screening. A total of 48 089 patients with aortic valve disease were identified, including 3 401 (7.1%) high-risk patients, 18 657 (38.8%) moderate-risk patients, and 26 031 (54.1%) low-risk patients. Among them, 2 417 patients were enrolled in whole-life cycle management. Patient satisfaction scores showed a yearly increase, rising from 73.89 points before 2020 to 93.74 points in 2024. The 1-year mortality rate in the TAVR cohort decreased to 5.3%, significantly lower than the 8.2% observed under early standard management between 2014 and 2019 (P<0.01). Conclusion Through process optimization and resource integration, the VHD whole-life cycle management model has demonstrated significant effectiveness in standardizing diagnostic and follow-up procedures, enhancing patient satisfaction and quality of life, and reducing mortality. These outcomes highlight its practical value for broader implementation in China.

Aim To investigate the mechanism of ligu aged 2 months of the same strain were used as the constilide (LIG) in delaying the senescence of auditory trol (Ctrl) group. Auditory brainstem response test was cortex and treating central presbycusis. Methods used to detect the auditory threshold of mice before and Forty C57BL/6J mice aged 13 months were randomly di after treatment. Levels of serum MDA and activity of vided into ligustilide low-dose(L-LIG) group, ligustil serum SOD were detected to display the level of oxidative ide medium-dose (M-LIG) group, ligustilide high-dose stress. The pathological changes of auditory cortex were (H-LIG) group and aging (Age) group, and 10 mice observed by HE staining. Ferroptosis was observed by

ObjectiveTo investigate the safety and efficacy of endoscopic retrograde cholangiopancreatography （ERCP） combined with electrohydraulic lithotripsy under the direct view of eyeMax biliary-pancreatic imaging system in the treatment of difficult choledocholithiasis. MethodsA retrospective analysis was performed for the clinical data of 12 patients with difficult choledocholithiasis who underwent ERCP and electrohydraulic lithotripsy under the direct view of eyeMax biliary-pancreatic imaging system in Department of Gastroenterology， Jilin People’s Hospital， from May to November 2022. The clinical effect of lithotripsy and lithotomy was observed， and postoperative complications and time of surgical operation were assessed. ResultsAmong the 12 patients， 11 （91.67%） were successfully treated by electrohydraulic lithotripsy under direct view， 9 （75.00%） achieved first-attempt success in lithotripsy， and 11 （91.67%） had complete removal of calculi； 1 patient was found to have stenosis of the bile ducts caused by multiple biliary tract surgeries， and grade Ⅱ intrahepatic bile duct stones above the sites of stenosis were removed under direct view， but there were still residues of grade Ⅲ intrahepatic bile duct stones， which led to the fact that complete calculus removal was not achieved. The mean time of ERCP operation was 91.3±26.2 minutes， including a time of 41.8±22.2 minutes for energy lithotripsy. There were 2 cases of postoperative biliary tract infection which were improved after anti-infective therapy， 2 cases of hyperamylasemia which were not given special treatment， and 3 cases of mild pancreatitis which were improved after symptomatic medication， and there were no complications such as bleeding and perforation. ConclusionERCP combined with electrohydraulic lithotripsy under the direct view of eyeMax biliary-pancreatic imaging system is safe， effective， and feasible in the treatment of difficult choledocholithiasis.

Objective To investigate the application effects of cardiac resynchronization therapy(CRT)of[left bundle optimization(LOT)]and biventricular pacing(BiV)in the patients with chronic heart failure complicating left bundle branch block.Methods The single center,prospective and non-randomized controlled study method was used.Forty-two patients with heart failure meeting CRT in this center from April 2020 to April 2022 were consecutively included.Among them,32 cases adopted the BiV-CRT(BiV-CRT group)and 10 cases adopted LOT-CRT(LOT-CRT group).The pacing-making parameters,quality of life scale(SF-36)score,6-min walk test(6-MWT),ECG QRS width(QRSd),left ventricular end-diastolic diameter(LVEDD),left ventricular ejection fraction(LVEF)and New York cardiac function grade(NYHA)situation were collected before surgery,after surgery immediately and in postoperative 3,6,12 months.Their complica-tions and clinical outcomes were evaluated.Results The pacing threshold value in the LOT-CRT group was stable and lower than that in the BiV-CRT group(P＜0.05);QRSd in postoperative 12 months in the LOT-CRT group was shorter than that in the BiV-CRT group[(115.0±14.3)ms vs.(133.0±14.0)ms,P＜0.05]and 6-MWT was longer than that in the BiV-CRT group[(327.0±52.8)m vs.(274.0±52.8)m,P＜0.05],and the differences were statistically significant(P＜0.05);LVEF,LVEDD,NYHA cardiac grade and SF-36 score in postoperative 12 months were improved compared with those before implantation.The rehospitaliza-tion rate of heart failure in the LOT-CRT group was lower.Conclusion LOT-CRT could obtain a narrower QRS wave and longer 6-MWT than BiV-CRT.

Objective To observe the incidence of pericardial tamponade(PT)after left atrial appendage closure(LAAC)in patients with non-valvular atrial fibrillation(NVAF),and to explore its related factors and outcomes.Methods NVAF patients who were hospitalized and treated with LAAC in Department of Cardiology of our hospital from August 2014 to March 2023 were selected for the study.The general clinical data,preoperative transthoracic echocardiography and transesophageal echocardiography data,results of routine preoperative laboratory tests,intraoperative data and follow-up data of the patients were collected through the hospital medical record management system.The enrolled patients were classified into the non-PT group(n=8)and the PT group(n =1184)according to whether PT occurred after LAAC or not.The incidence of PT,related risk factors and outcomes were statistically analyzed.Results This study included 639 males(53.6%)and 553 females(46.4%),with an average age of 68.1±9.65 years.The CHA2 DS2-VASc score was 4.51±1.72,and the HAS-BLED score was 3.36±1.09.PT occurred in 8 cases(0.67%),among them,6 cases occurred 1 to 33 h after LAAC,and 2 cases occurred on day 19 and day 27 after LAAC.As for the results of transesophageal echocardiography(TEE)and LAA angiography,compared with the non-PT group,the PT group had the significantly larger maximum caliber of the LAA(P=0.025,P=0.015),smaller maximum depth of the LAA(P=0.028,P=0.031),and lower success rate of one-time placement of the occluder(P=0.031);The occluder compression rate of the PT group was significantly greater than that of the non-PT group(P=0.046).Multivariate analysis showed that larger maximum diameter of LAA,smaller average effective depth of LAA and larger compression rate of occluder were the main risk factors for PT.All the 8 PT patients were cured by stopping antithrombotic drugs,pericardiocentesis or surgical drainage.During a mean follow-up of 39±27 months,there were no device-related thrombosis(DRT),ischemic stroke,systemic embolism and other complications in the PT group.Conclusion The incidence of PT after LAAC is low,which is related to the large diameter of LAA,the relatively insufficient depth of the LAA and the large compression rate of the occlude.PT can be cured by stopping antithrombotic drugs and pericardiocentesis/surgical drainage.

BACKGROUND:As tissue engineering brings new hope to the worldwide problem of articular cartilage repair,the construction of light-curing 3D printed hydrogel scaffolds with biomimetic composition is of great significance for cartilage tissue engineering. OBJECTIVE:To construct a biomimetic methacryloylated hyaluronic acid/acellular Wharton's jelly composite hydrogel scaffold by digital light processing 3D printing technology,and to evaluate its biocompatibility. METHODS:Wharton's jelly was isolated and extracted from human umbilical cord,then decellulated,freeze-dried,ground into powder,and dissolved in PBS to prepare 50 g/L acellular Wharton's jelly solution.Methylallylated hyaluronic acid was prepared,lyophilized and dissolved in PBS to prepare 50 g/L methylallylated hyaluronic acid solution.Acellular Wharton's jelly solution was mixed with methacrylyacylated hyaluronic acid solution at a volume ratio of 1:1,and was used as bio-ink after adding photoinitiator.Methylacrylylated hyaluronic acid hydrogel scaffolds(labeled as HAMA hydrogel scaffolds)and methylacrylylated hyaluronic acid/acellular Wharton's jelly gel scaffolds(labeled as HAMA/WJ hydrogel scaffolds)were prepared by digital light processing 3D printing technology,and the microstructure,swelling performance,biocompatibility,and cartilage differentiation performance of the scaffolds were characterized. RESULTS AND CONCLUSION:(1)Under scanning electron microscope,the two groups of scaffolds showed a three-dimensional network structure,and the fiber connection of HAMA/WJ hydrogel scaffold was more uniform.Both groups achieved swelling equilibrium within 10 hours,and the equilibrium swelling ratio of HAMA/WJ hydrogel scaffold was lower than that of HAMA hydrogel scaffold(P＜0.05).(2)CCK-8 assay showed that HAMA/WJ hydrogel scaffold could promote the proliferation of bone marrow mesenchymal stem cells compared with HAMA hydrogel scaffold.Dead/live staining showed that bone marrow mesenchymal stem cells grew well on the two groups of scaffolds,and the cells on the HAMA/WJ hydrogel scaffolds were evenly distributed and more cells were found.Phalloidine staining showed better adhesion and spread of bone marrow mesenchymal stem cells in HAMA/WJ hydrogel scaffold than in HAMA.(3)Bone marrow mesenchymal stem cells were inoculated into the two groups for chondrogenic induction culture.The results of qRT-PCR showed that the mRNA expressions of agglutinoglycan,SOX9 and type Ⅱ collagen in the HAMA/WJ hydrogel scaffold group were higher than those in the HAMA hydrogel scaffold group(P＜0.05,P＜0.01).(4)These findings indicate that the digital light processing 3D bioprinting HAMA/WJ hydrogel scaffold can promote the proliferation,adhesion,and chondrogenic differentiation of bone marrow mesenchymal stem cells.

The working principle and development of flexible semiconductor devices based on organic field effect transistor(OFET)technology were introduced.The current research status of OFET-based wearable flexible monitoring devices were reviewed,including biomechanical monitoring devices,tattoo biomonitoring devices and cellular detection devices and etc.The deficiencies of OFET-based wearable flexible monitoring devices were analyzed,and it's pointed out that miniaturization,personalization and diversification were the directions for the development of the future OFET-based wearable flexible moni-toring devices.[Chinese Medical Equipment Journal,2024,45(1):93-100]

ObjectiveTo analyze the causes of occupational acute 1,2-dichloroethane (1,2-DCE) poisoning accident during the use of polyurethane grouting materials for waterproof plugging operation in the construction industry. Methods By combining the clinical symptoms of the patient, worksite survey of occupational health and workplace occupational hazards monitoring method, the cause of an occupational acute 1,2-DCE poisoning accident was investigated at a construction site during the use of polyurethane grouting material for waterproofing and plugging operations. Results The patient was engaged in waterproof grouting work using polyurethane grouting material. The main volatile organic components in the raw materials were 1,2-DCE, with traces of dichloromethane, methyl acetate and others. The result of post-incident on-site investigation showed that the short-term exposure concentration of 1,2-DCE in the workplace air was 578.70 mg/m³, which was more than 30 times higher than the national occupational health standard limit. The mass concentration of 1,2-DCE in the patient's blood was 230 μg/L. Combined with the patient's occupational hazard exposure history, clinical manifestations, worksite survey of occupational health, and laboratory test results, according to GBZ 39-2016 Diagnosis of Occupational Acute 1,2-Dichloroethane Poisoning, this incident was diagnosed as a severe occupational acute 1,2-DCE poisoning event caused by the use of inferior polyurethane grouting material. Conclusion The excessive concentration of 1,2-DCE in the workplace air is the main cause of this poisoning accident. Construction sites with confined space operations should improve various occupational health management systems, occupational health engineering protective facilities, and personal protective equipment must be provided for workers.

ObjectiveOur recent study has demonstrated that extracellular acidification promotes lipid accumulation in macrophages via the activation of acid sensing ion channel 1 (ASIC1), but the underlying mechanism remains unclear. This study aims to explore the effect of extracellular acidification on macrophage lipophagy and the underlying mechanism. MethodsRAW264.7 macrophages were incubated with 25 mg/Lox-LDL in a pH 6.5 culture medium for 24 h to build macrophage-derived foam cell models induced by extracellular acidification. Then, RAW264.7 macrophages were cultured in the acidic medium of pH 6.5 with or without PcTx-1 (ASIC1 specific blocker, 10 μg/L) or Nec-1 (RIP1 specific inhibitor, 20 μmol/L) for 24 h, intracellular lipid accumulation was observed by oil red O staining. The expressions of total ASIC1, plasma membrane ASIC1, RIP1, p-RIP1 Ser166, TFEB, p-TFEB Ser142, LC3 and p62 were measured by Western blot. The co-localization of lipids (indicated by Bodipy) with LC3II (autophagosomes) and LAMP1 (lysosomes) was analyzed by a confocal laser scanning microscopy, respectively. Morphological changes of lipophagy in the cells were observed by using transmission electron microscopy. ABCA1-mediated cholesterol efflux was determined by cholesterol fluorescence kits. ResultsCompared with pH 7.4+ox-LDL group, the intracellular lipid accumulation in the pH 6.5+ox-LDL group was significantly increased. Meanwhile, the expressions of plasma membrane ASIC1, p-RIP1 Ser166, p-TFEB Ser142, and p62 proteins were elevated significantly, while LC3II protein level and LC3II/LC3I ratio were decreased. Accordingly, compared with pH 7.4+ox-LDL group, the macrophage lipophagy of the pH 6.5+ox-LDL group was inhibited as indicated by the decreased localization of lipid droplets with LC3 and LAMP1, a decrease in the number of lipophagosomes as well as an increase in lipid droplets. Furthermore, ATP binding cassette transporter A1 (ABCA1)-dependent cholesterol efflux from the macrophages of pH 6.5+ox-LDL group reduced dramatically. However, these above effects of extracellular acidification on RAW264.7 macrophages were abolished by PcTx-1 and Nec-1, respectively. ConclusionThese findings suggest extracellular acidification promotes the phosphorylation of TFEB at Ser142 via activating ASIC1/RIP1 pathway, thereby impeding lipophagy in RAW 264.7 macrophages, and that ASIC1 may be a new potential target for preventing aberrant lipid accumulation diseases including atherosclerosis.