Objective To explore the efficacy of neuromuscular electrical stimulation (NMES) in treating severe and chronic obstructive pulmonary disease (COPD).Methods Seventy-eight COPD patients were randomly divided into an NMES group of 38 and an exercise therapy group of 32.In addition to the routine drug therapy and basic rehabilitation training,the NMES group received 8 weeks of NMES of the lower limbs while the exercise group was provided with strength and endurance training of the lower limbs,also for 8 wceks.Before and after the 8 weeks of treatment,pulmonary function was tested along with isokinetic quadriceps strength,cardiopulnonary capacity,and lung capacity using Saint George's respiratory questionnaire (SGRQ).Results The two groups showed no significant difference in any of the measurements before the treatment.After the treatment,forced expiratory volume in 1 second of (FEV1),FEV1/forced vital capacity (FVC),FEVI in percentage of the predicted value,medical research council dyspnea scale (MRC) score and the 6-minute walk distance (6MWD) improved in both groups.However,the average body mass index and 6 minute walk distance differed significantly between the groups after the treatment.The quadriceps' peak torque increased after the treatment in both groups,but the average in the exercise group was significantly higher than that in the NMES group.VO2max and Wmax also increased significantly in both groups,and the average time to exhaustion increased significantly in the exercise group.Significant improvement was observed in the BODE assessment after the intervention for both groups.Conclusion Neuromuscular electrical stimulation is as effective as therapeutic exercise in promoting the rehabilitation of severe COPD patients.However,lower limbs exercise is still the first choice in managing such patients.

Tbx18,Wt1,and Tcf21 have been identified as epicardial markers during the early embryonic stage.However,the gene markers of mature epicardial cells remain unclear.Single-cell transcriptomic analysis was performed with the Seurat,Monocle,and CellphoneDB packages in R software with standard pro-cedures.Spatial transcriptomics was performed on chilled Visium Tissue Optimization Slides(10x Genomics)and Visium Spatial Gene Expression Slides(10x Genomics).Spatial transcriptomics analysis was performed with Space Ranger software and R software.Immunofluorescence,whole-mount RNA in situ hybridization and X-gal staining were performed to validate the analysis results.Spatial transcriptomics analysis revealed distinct transcriptional profiles and functions between epicardial tissue and non-epicardial tissue.Several gene markers specific to postnatal epicardial tissue were identified,including Msln,C3,Efemp1,and Upk3b.Single-cell transcriptomic analysis revealed that cardiac cells from wildtype mouse hearts(from embryonic day 9.5 to postnatal day 9)could be categorized into six major cell types,which included epicardial cells.Throughout epicardial development,Wt1,Tbx18,and Upk3b were consistently expressed,whereas genes including Msln,C3,and Efemp1 exhibited increased expression during the mature stages of development.Pseudotime analysis further revealed two epicardial cell fates during maturation.Moreover,Upk3b,Msln,Efemp1,and C3 positive epicardial cells were enriched in extracellular matrix signaling.Our results suggested Upk3b,Efemp1,Msln,C3,and other genes were mature epicardium markers.Extracellular matrix signaling was found to play a critical role in the mature epicardium,thus suggesting potential therapeutic targets for heart regeneration in future clinical practice.