Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

Objective:To evaluate the long-term effectiveness of lingual mucosal graft ureteroplasty (LMGU) for managing long-segment (≥5 cm) ureteral strictures in a multi-institutional cohort of patients.Methods:A multi-center retrospective case series study was conducted on clinical data from 42 patients undergoing LMGU for long-segment ureteral strictures (≥5 cm) across five institutions between February 2017 and June 2024. The cohort comprised 31 males and 11 females, with an age of (43.4±12.0) years (range: 15 to 64 years) and a body mass index of (24.6±2.6) kg/m2 (range: 16.0 to 30.0 kg/m2). Strictures involved the left ureter in 24 cases and right ureter in 18 cases, demonstrating a stricture length of (6.4±1.5) cm (range: 5.0 to 11.5 cm). Surgical interventions included either onlay ureteroplasty or augmented anastomotic ureteroplasty, selected according to intraoperative findings. Intraoperative parameters, postoperative complications, and follow-up outcomes were analyzed.Results:Laparoscopic surgery was performed in 22 cases and robot-assisted surgery in 20 cases. Among the 42 patients, 22 underwent onlay ureteroplasty while 20 received augmented anastomotic ureteroplasty. The graft length was (5.9±1.8) cm (range: 3.0 to 12.0 cm), operative time (191.5±55.6) minutes (range: 105.0 to 350.0 minutes), and intraoperative estimated blood loss (86.7±73.6) ml (range: 10.0 to 400.0 ml). All procedures were successfully completed without conversion to open surgery. The postoperative hospital stay was (7.6±2.0) days (range: 4.0 to 15.0 days), with double-J stent removal at 6 to 8 weeks postoperatively. During a follow-up of (49.1±25.0) months (range: 12.0 to 99.0 months), no stricture recurrence was observed in any patient.Conclusion:LMGU is a safe, feasible, and effective long-term technique for managing long-segment (≥5 cm) ureteral strictures.

Objective:To investigate the incidence of shoulder work-related musculoskeletal disorders (WMSDs) among occupational population in China, and to explore their intrinsic association with personal and work-related factors.Methods:In April 2024, 73497 valid questionnaires of the Chinese version of the Musculoskeletal Disorders Electronic Questionnaire were retrospectively analyzed from June 2018 to December 2023 in 22 provinces and 29 key industries in China, and the general information, occurrence of WMSDs and related risk factors of key occupational populations in different regions in China were collected. By using Chi-square test and confirmatory factor analysis, the relationship between shoulder fatigue and pain in key occupational groups and individual factors, work type, work posture and work organization was discussed, and the internal relationship was analyzed based on structural equation model.Results:Higher incidence of shoulder fatigue and pain were associated with female, lack of physical exercise, uncomfortable working posture and neck leaning forward ( P<0.05). Structural equation model analysis showed that work type, work posture and work organization were strongly correlated ( r=0.58, 0.55). Work organization and work type were strongly correlated with shoulder fatigue ( r=0.65) and moderately correlated with shoulder fatigue ( r=0.21). Shoulder fatigue was moderately associated with shoulder pain ( r=0.40). Individual factors, work type, work posture and shoulder fatigue could directly affect shoulder pain ( OR=0.07, -0.09, 0.17 and 0.40), and work type and work posture could also indirectly affect shoulder pain through shoulder fatigue ( OR=0.08, 0.03). Work organization only indirectly affected shoulder pain through shoulder fatigue ( OR=0.26) . Conclusion:The main influencing factor of shoulder pain is shoulder fatigue, followed by work posture and individual factors. Structural equation model can better reflect the complex relationship between work type, work posture and work organization and shoulder WMSDs. Improving work posture and work organization may be an effective way to control the influence of shoulder fatigue on shoulder pain.

Objective:To explore the structural equation model to explore the levels of work-related musculoskeletal disorders (WMSDs) and various risk factors in the feet and ankle of China's occupational population, providing scientific basis for for preventing WMSDs in feet and ankles.Methods:Data of 73497 national occupational epidemiological cases were selected from June 2018 to December 2023 used the Chinese version of the Electronic Questionnaire on Musculoskeletal Disorders. The adverse ergonomic factors and their source classification standard and confirmatory factor analysis were used to investigate foot and ankle WMSDs and their related risk factors (including individual factors, work organization, work posture, work type, fatigue, etc.) in key occupational groups in China, and structural equation model hypothesis, fitting, verification, and path and intermediary effect analysis were carried out. The model fit evaluation indexes included Chi-square specific degrees of freedom ( χ2/ df), gauge fit index (NFI), Tucker Lewis index (TLI), goodness of Fit index (GFI), adjusted Goodness of Fit index (AGFI) and approximate root mean square error (RMSEA) . Results:A total of 73497 occupational workers were surveyed, with local muscle fatigue and WMSDs incidence rates in the feet and ankles being 17.17% and 12.06%, respectively. The fitting index of the adjusted structural equation model basically meets the standard (GFI=1, AGFI=1, RMESA=0.042, NFI=0.716, TLI=0.663). The top three factors affecting feet and ankle WMSDs are feet and ankle muscle fatigue, work type, and work organization, with standardized path coefficients of 0.221, 0.105, and 0.095, respectively. The top two factors affecting feet and ankle muscle fatigue are work organization and work type, with standardized path coefficients of 0.548 and 0.383, respectively. Feet and ankle muscle fatigue, work type, work organization, and work posture have a direct effect on feet and ankle WMSDs, with effect values of 0.221, 0.105, 0.095, and 0.077, respectively. The organization and type of work can also have indirect effects through feet and ankle muscle fatigue, with effect values of 0.121 and 0.084, respectively.Conclusion:Feet and ankle muscle fatigue has a direct impact on WMSDs, and plays a mediating role between ankle and ankle WMSDs caused by work organization and work type. Feet and ankle muscle fatigue is an important pathway leading to feet and ankle WMSDs. It is recommended that employers and managers detect job fatigue early and take corresponding prevention and intervention measures, which can play a key role in preventing feet and ankle WMSDs.

Objective:To explore the structural relationship between WMSDs in the upper limbs and various risk factors in the occupational population in China, based on a large sample epidemiological survey and structural equation analysis, and to establish a structural equation model, so as to lay a foundation for the prevention and control of such diseases.Methods:The Chinese version of the Musculoskeletal Disorders Electronic Questionnaire was used to conduct a nationwide survey on the prevalence of WMSDs in the upper extremity. Six factors related to WMSDs in the upper extremity were extracted by the classification standard of adverse ergonomic factors and their source and confirmatory factor analysis, including work organization, work type, upper extremity work posture, individual factors, upper extremity fatigue and upper extremity WMSDs. The structural equation analysis was carried out and the structural equation model was established.Results:The incidence of WMSDs and fatigue in the upper limbs was 24.44% and 43.76%, respectively. The adjusted structural equation model fitting indicators were generally up to the standard (GFI=1.000, AGFI=1.000, RMSEA=0.043, NFI=0.808, TLI=0.784) . The four exogenous latent variables of work organization, work type, upper limb work posture and individual factors were correlated. There was a strong positive correlation between job type and upper limb work posture ( r=0.865) , a moderate positive correlation between work organization and job type and upper limb work posture ( r=0.570, 0.490) , and a weak negative correlation between individual factors and the other three exogenous latent variables. Upper limb work posture and individual factors had direct effects on upper limb WMSDs, and the effect coefficients were 0.10 and 0.06, respectively. Upper limb fatigue played a mediating role between work organization, work type, upper limb work posture and upper limb WMSDs. The effect coefficient was 0.46, and the composition ratios of indirect effects were 100.0%, 100.0%, and 38.3%, respectively. The direct path effect of upper limb work posture, individual factors and upper limb WMSDs was weaker than the mediating path through upper limb fatigue. Conclusion:When carrying out the prevention and control of upper limbWMSDs, it is necessary to comprehensively consider the pathogenesis path of upper limb muscle fatigue and upper limb WMSDs caused by work organization, work type, and upper limb work posture, so as to provide theoretical reference for improving the prevention and control level of such diseases.

Objective:To analyze the dynamic changes of serum exosome miR-552 and miR-653 levels in pa-tients with gastric cancer before and after chemotherapy and their relationship with clinical benefit.Methods:IA total of 128 patients with gastric cancer received chemotherapy from January 2022 to January 2024.According to the chemo-therapy effect,the two groups were divided into disease progression group and disease remission group.The levels of serum exosome miR-552 and miR-653 before and after chemotherapy were detected in the two groups,the risk fac-tors affecting the chemotherapy effect of gastric cancer patients were screened,the risk nomogram model was con-structed,and the efficacy was evaluated.Results:The proportion of TNM stage(Ⅲ+Ⅳ),lymph node metastasis,dis-tant metastasis,tumor size(>5 cm),invasion depth(T3/T4)and tumor growth pattern(invasive type)in disease progres-sion group was higher than that in disease remission group(P<0.05).The levels of serum exosomes miR-552 and miR-653 in disease progression group were higher than those in remission group before and after chemotherapy(P<0.05).Compared with before chemotherapy,miR-552 and miR-653 levels in both groups decreased(P<0.05).Logistic regres-sion analysis showed that TNM stage,lymph node metastasis,distant metastasis,tumor size,invasion depth,miR-552 and miR-653 were all risk factors affecting the chemotherapy efficacy of gastric cancer(P<0.05).ROC curve results showed that the AUC,95%CI,sensitivity and specificity of risk nomogram model to predict chemotherapy efficacy of gastric cancer were 0.867,0.672～0.991,92.80%and 80.40%,respectively(P<0.001).Calibration curve results showed that both predicted and actual predicted values were near the ideal curve,and the Hosmer-Lemeshow goodness of fit curve test χ2=1.869,P=0.782.Conclusion:The levels of serum exosomes miR-552 and miR-653 are closely related to the chemotherapy efficacy of gastric cancer,and dynamic monitoring of the above indexes is helpful for the evaluation of the disease and prognosis of gastric cancer.In this study,the risk nomogram model constructed based on the above indexes and other risk factors has high predictive value and clinical practicability for chemotherapy efficacy in patients with gastric cancer.

Aim To infer novel therapeutic and phar-macological targets related to lung cancer treatment through multiomics approaches,so as to provide new directions for developing more personalized and effec-tive treatment strategies.Methods Genome-wide as-sociation study(GWAS)data analysis,pan-cancer,single-cell,transcriptomics,and protein-protein interac-tion analysis were employed in this study.Results We analyzed biomarkers and therapeutic targets associ-ated with lung cancer.The study identified key bio-markers closely related to lung cancer progression and explored the interrelationships between these biomark-ers and viral infections.According to KEGG pathway annotation,the number of genes related to metabolic processes increased significantly.In particular,metab-olites such as alanine and isoleucine emerged as pivotal factors in therapeutic interventions.The IgD+CD24+and IgD+CD24-B cell subsets were identified as cen-tral elements in immune evasion and treatment re-sponse.Concurrently,the Lachnospiraceae and Prevo-tella were shown to modulate host immune responses and the tumor microenvironment by regulating short-chain fatty acid levels,thereby opening novel avenues for cancer research.Conclusions Through mul-tiomics analysis combined with transcriptomics and pro-teomics analysis,we identify several potential therapeu-tic targets for lung cancer,providing key insights for developing novel treatment strategies.

Objective To comparatively analyze the quantitative parameters of culprit and non-culprit plaques in patients with acute coronary syndromes(ACS)with a noninvasive technique of coronary computed tomography angiography(CCTA),and to explore the correlation between the quantitative parameters of plaques and culprit plaques.Methods Data were restrospectively collected from 51 ACS patients admitted in some hospital from January to December 2021.The coronary atherosclerotic plaques shown by invasive catheter angiography(ICA)that caused hemodynamic abnormalities and were treated with stenting were defined as offender plaques and enrolled into a culprit plaque group(56 culprit plaques),and other plaques were regarded as non-culprit plaques and divied into a non-culprit plaque group(164 non-culprit plaques).The relationship between culprit plaque and luminal stenosis was analyzed using the chi-square test,and quantitative plaque metrics were compared between the groups.The corelation between quantitative indicators and culprit plaque was analyzed using univariate Logistic regression,and multifactorial Logistic regression analysis was carried out.Statistical analysis was performed with SPSS 23.0 software.Results Analysis of plaque imaging data showed that culprit plaque was significantly associated with the degree of luminal stenosis(P<0.05).Statistically significant differences were found beween the two groups and between the culprit plaques resulting in moderate or greater luminal stenosis and non-culprit plaques in total plaque length,total plaque load,calcification load,fibrolipid volume,fibrolipid load,necrotic core volume and necrotic core load(all P<0.05).Univariate Logistic regression analysis showed total plaque length,total plaque load,fibrolipid volume,fibrolipid load,necrotic core volume and necrotic core load were all significantly correlated with culprit plaques(all P<0.05);multifactorial Logistic regress indicated total plaque length and fibrous lipid load were independent risk factors for culprit plaques,and the probability of culprit plaques increased to 1.093 and 1.101 times for every one unit increase in total plaque length and fibrolipid load,respectively.Conclusion Such quantitative parameters of plaques as total plaque length,total plaque load,fibrolipid volume,fibrolipid load,necrotic core volume and necrotic core load reflects the characteristics of culprit plaques effectively.Quantitative plaque parameter analysis based on CCTA facilitates clinicians for early assessment of patients with coronary atherosclerosis,which enables early intervention and prevention of acute coronary syndromes.[Chinese Medical Equipment Journal,2025,46(6):65-71]

Objective To explore the effects of hypoxia on spermatid differentiation and stability of sperm flagellar microtubule,and investigate the underlying molecular mechanisms in order to clarify the potential adverse effects of hypoxia on male reproductive function.Methods Forty-eight 8-week-old healthy male SD rats(weighing 300～399 g)were subjected in this study.The experiments included ① an oxygen concentration gradient experiment(n=6):21％oxygen was regarded as normoxia(control),and 13.5％,11.8％,and 10.4％ oxygen were used to simulate hypoxic environments at altitudes of 3 500,4 500 and 5 500 m,respectively,for a continuous exposure of 2 months;② a time gradient experiment(n=6):the rats were exposed to 10.4％ oxygen for 0,0.5,1,and 2 months,respectively.Flow cytometry was employed to isolate round spermatids,and the following methods were employed to measure relevant indicators:① RNA sequencing to analyze gene expression profile changes related to impaired spermatogenesis and abnormal flagellar structure under hypoxic stress;②Western blotting to detect the expression levels of key proteins CEP290,RING 1A,and H2AK119ub;③ fluorescence recovery after photobleaching(FRAP)to monitor microtubule assembly dynamics and assess the immediate impact of hypoxia on microtubule stability.Results In the oxygen concentration gradient experiment,after 2 months of exposure to 10.4％ oxygen,the proportions of spermatogonia,secondary spermatocytes,and round spermatids in rat seminiferous tubules were significantly increased(P＜0.05),reaching 1.33±0.04,1.06±0.01 and 1.60±0.02 times higher,respectively than that of the 21％ normoxia group.Conversely,the proportions of primary spermatocytes and elongated spermatids were obviously decreased(P＜0.05),taking 0.89±0.01 and 0.88±0.000 2 times respectively when compared with that of the 21％ normoxia group,in a oxygen concentration-depended manner.In the time gradient experiment,after 0.5 months of exposure to 10.4％oxygen,the proportions of spermatogonia,secondary spermatocytes,and round spermatids began to increase(P＜0.05),reaching 1.11±0.03,1.04±0.01 and 1.29±0.003 times higher,respectively than that of the 0-month control group.The proportions of primary spermatocytes and elongated spermatids started to significantly decrease(P＜0.05)after 1 month of exposure,only 0.94±0.03 and 0.95±0.008 times,respectively than that of the 0-month control group.After 2 months of exposure to 10.4％ oxygen,the rate of sperm tail abnormalities in the epididymis of rats was significantly increased(P＜0.05),rising from(12.1±1.7)％ in the 21％ normoxia group to(30.8±3.7)％.In G2 spermatocytes exposed to 1％ hypoxia for 24 h,FRAP revealed a decrease in microtubule assembly rate and enhanced microtubule dynamic instability,with the maximum fluorescence recovery value decreasing from 0.37±0.02 in the normoxia group to 0.29±0.01.The results of RNA sequencing showed that under hypoxic condition,the transcription level of the key cilium basal body molecule CEP290 was increased,with an upregulation of 1.81±0.11 times than that of the 21％ normoxia group.In contrast,the expression levels of PRC1 complex members RING 1A,RING 1B,CBX2,PHC1,and PCGF1 were decreased,to 0.74±0.02,0.73±0.01,0.78±0.02,0.71±0.01 and 0.86±0.03 times of that of the 21％ normoxia group,respectively.Western blotting indicated that the protein level of CEP290 was up-regulated in the hypoxia group,while that of RING 1A was down-regulated.ChIP-qPCR experiments showed that the binding of RING 1A and its product H2AK119ub to the CEP290 promoter were significantly decreased(P＜0.000 1),with binding strengths of 0.38±0.02 and 0.52±0.06 times of that of the 21％ normoxia group,respectively.In siRING 1A-treated G2 cells,the binding of H2AK119ub to the CEP290 promoter was significantly decreased(P＜0.000 1),with a binding strength of 0.74±0.06 times of that of the control group,while CEP290 mRNA level was significantly increased(P＜0.000 1),with an up-regulation of 3.35±0.37 times.Conclusion Hypoxic environment impair sperm flagellar microtubule stability via the RING 1A-H2AK119ub-CEP290 signaling axis,which affects spermatid differentiation and leads to spermatogenic dysfunction.

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.