The research and development of innovative drug have progressed remarkably, but the long development circle and high failure rate have become the bottleneck. Drug repurposing, discovering new indications of approved drugs, is a strategy to overcome these obstacles. By exploring new indications for approved drugs, rapid progress has been made in basic research and clinical translation in recent years. Rich resources of drugs, proven security, efficient development workflow and reduced cost are core advantages of this strategy, making the strategy a crucial direction of optimizing the pipeline of drug research and development. This review systematically summarizes drug repurposing cases that have received clinical approval over the past five years, and proposes core strategies for drug repurposing, including approaches based on targets, pathways, drug similarity, post-treatment phenotypes, and clinical side effects, aiming to provide some strategic guidance for drug repurposing efforts.

BACKGROUND:Traditional methods of urinary tract reconstruction are limited by donor scarcity,high complication rates,and suboptimal functional recovery.Tissue engineering strategies offer new directions in this field.Since the urinary tract is mainly composed of muscle tissue,the key is to find suitable seed cells and efficiently induce them to differentiate into smooth muscle cells.Comparative studies on the efficacy of different smooth muscle cell induction regimens are still lacking. OBJECTIVE:To isolate,culture,and identify human urine-derived stem cells,and to compare the effects of two different induction protocols. METHODS:Human urine-derived stem cells were isolated from urine samples of 11 healthy adult volunteers by multiple centrifugations.Surface markers were identified by flow cytometry.The multi-directional differentiation potential of human urine-derived stem cells was verified through osteogenic and adipogenic differentiation.Differentiation was induced by transforming growth factor-β1 or transforming growth factor-β1 combined with platelet derived growth factor for 14 days.Immunofluorescence staining and western blot assay were employed to compare the expression differences of smooth muscle-specific proteins(α-SMA and SM22). RESULTS AND CONCLUSION:(1)Urine-derived stem cells were successfully isolated from the eight urine samples of healthy people.These cells exhibit a"rice grain"-like morphology and possess a robust proliferative capacity.(2)Urine-derived stem cells exhibited high expression of mesenchymal stem cell surface markers(CD73,CD90,and CD44)and extremely low expression of hematopoietic stem cell surface markers(CD34 and CD45).These cells did not express CD19,CD105,and HLA-DR.(3)After osteogenic and adipogenic differentiation,the formation of calcium nodules and lipid droplets was observed,with positive staining results from Alizarin Red S and Oil Red O staining.(4)After 14 days of smooth muscle induction culture,immunofluorescence staining revealed that the smooth muscle differentiation rate of urine-derived stem cells treated with a combination of transforming growth factor-β1 and platelet derived growth factor was significantly higher compared to those treated with transforming growth factor-β1 alone(P<0.005).(5)After 14 days of smooth muscle induction culture,western blot assay further demonstrated that the expression levels of α-SMA and SM22 in the transforming growth factor-β1/platelet derived growth factor group were significantly elevated compared to those in the transforming growth factor-β1 only group(P<0.005).These findings confirm that urine-derived stem cells can be non-invasively isolated using multiple rounds of centrifugation.Compared with transforming growth factor-β1 alone,the combination of transforming growth factor-β1 and platelet derived growth factor can improve the efficiency of inducing urine-derived stem cells to differentiate into smooth muscle cells.

Objective To investigate the protective effects of mitochondrial preconditioning in pericytes(PC)against pulmonary vascular leakage in septic rats.Methods ① 128 specific-pathogen-free SD rats(equal gender,200±20 g)were randomized into:Sham group(postoperative tail vein injection of 0.5 mL saline),Sepsis(Sep)group(CLP+saline),PC group(CLP+untreated PC:106 cells/rat),and Mito-PC group(CLP+PC preconditioned with 2 μg mitochondria/104 cells for 12 h).Assessments included:PC lung colonization(flow cytometry),pulmonary barrier function(Evans blue assay),lung histopathology(HE staining),serum organ injury markers[cTnT(cardiac),urea/creatinine(renal)],and inflammatory cytokines(TNF-α,IL-6).② MSC-derived mitochondria were validated by electron microscopy/flow cytometry;primary retinal PCs from weaned SD rats were purity-verified(confocal microscopy).In vitro groups:Control(PC),Mito-PC,PC+H2O2(0.5 μmol/L,4 h),and Mito-PC+H2O2.Antioxidant capacity was assessed via pentose phosphate pathway(PPP)activity,NADPH levels,G6PD activity,and NADP+/NADPH ratio.Results① Compared with Sham,Sep group showed significant increase in pulmonary leakage(Evans blue P<0.05),severe lung injury,elevated serum markers(TNF-α,IL-6,cTnT,urea,creatinine all P<0.05),0％72 h survival.PC group showed partial improvement(P<0.05).Mito-PC group demonstrated significant reduction in vascular leakage(P<0.05 vs PC group),improved histopathology and organ function(P<0.05),attenuated inflammation(P<0.05),higher 72 h survival rate(P<0.05).② Mitochondrial preconditioning significantly enhanced PPP activation and NADPH-mediated antioxidative capacity,Mito-PC+H2O2 vs PC+H2O2 showed improved cell viability(P<0.05),Mito-PC vs PC showed increased G6PD activity(P<0.05),decreased NADP+/NADPH ratio(P<0.05).Conclusion Mitochondrial preconditioning potentiates pericyte-mediated protection against sepsis-induced pulmonary vascular leakage through enhanced pentose phosphate pathway activity.Mitochondrial preconditioning potentiates pericyte-mediated protection against sepsis-induced pulmonary vascular leakage through enhanced pentose phosphate pathway activity.

Objective:To analyze the quality level of maternal mid-trimester serum prenatal screening in China from 2019 to 2023.Methods:A questionnaire survey was conducted to collect information from laboratories participating in the National Health Commission′s Clinical Laboratory Center inter-laboratory quality assessment program for prenatal screening from 2019 to 2023. The collected data included screening protocols, detection methods, testing systems, and monthly laboratory screening quality indicators. The Chi-square test was used to compare the initial screening positive rates among different screening protocols, provinces, detection methods, and testing systems. A log-transformed linear regression analysis was performed to evaluate the relationship between the average annual sample size and the out-of-control rate of various median multiple of the median (mMoM) values.Results:This study included 806 laboratories from 29 provinces (including autonomous regions and municipalities). The five-year average out-of-control rates for mMoM values across indicators ranged from 15.8% to 31.3%. The initial positive rates of dual, triple, and quadruple screening protocols were statistically different ( χ2=760.2, P<0.001). The initial positive rates across different provinces ranged from 4.7% to 10.3%, with statistically significant differences ( χ2=35 388.0, P<0.001). There were also statistically significant differences in initial positive rates between different testing systems ( χ2=2 493.2, P<0.001). Testing systems using chemiluminescence methods had significantly higher initial positive rates compared to systems using time-resolved fluorescence methods (7.2% vs. 6.5%, χ2=533.6, P<0.001). Log-linear regression analysis showed that testing systems with larger annual average sample sizes had lower out-of-control rates for mMoM values (AFP: β=-0.100, P=0.005; hCG: β=-0.123, P=0.008; uE3: β=-0.139, P=0.007). Conclusion:There are significant differences in the quality of maternal mid-trimester serum screening across different detection methods, testing systems and provinces in China.

National mutual recognition of clinical laboratory test results is an important measure to improve the utilization of medical resources and reduce the economic burden of healthcare for the public. The essence of mutual recognition of test results is to ensure that the test results between different medical institutions are consistent and comparable, thereby avoiding duplicate testing and waste of medical resources, and improving the patient′s healthcare experience. The evaluation of comparability of inspection results, quality measurement and monitoring of mutual recognition laboratories and tests, as well as the development of quality evaluation indicators and technical requirements for mutual recognition laboratories, are the core issues for the realization of mutual recognition of inspection results nationwide. This article explores the quality evaluation indicators and technical requirements for mutual recognition of clinical laboratory test results nationwide to speed up this process.

Objective To understand the status of medical laboratories participating in external quality assessment(EQA)program in China.Methods The test covered by an EQA control rate and acceptable performance rate of theinformation collection and data analy-sis systems in the EQA program developed by National Center for Clinical Laboratories in medical laboratories of nationwide various re-gions were evaluated descriptively and analyzed statistically.Forty analytes in various disciplines were selected to analyze statistically the implementation of the testing items and participation retes of EQA program.Results The number of medical laboratories participat-ing in EQA program increased yearly from 592 in 2019 to 1 169 in 2023.The nationwide median test covered by an EQA control rate and acceptable performance rate of EQA program reached over 91％and 98％,respectively.In 2023,the median test covered by an EQA control rate of EQA program in the medical laboratories of nationwide regions showed that the median test covered by an EQA con-trol rate reached 100％in Gansu and Hainan regions,and the medians of acceptable performance rate reached 100％in Beijing,Guangdong,Hubei,Jiangsu,Shandong,Shanxi,Shanghai,Tianjin,Xinjiang,and Zhejiang regions.Among the 40 analytes,the test covered by an EQA control rate of only 6 EQA items were greater than 80％in nationwide medical laboratories,i.e.,rheumatoid factor,neonatal deafness gene detection,high throughput sequencing of peripheral fetal chromosome aneuploidy(T21,T18 and T13)by high throughput sequencing,thalassemia gene typing,hepatitis C virus RNA quantification,and EGFR gene mutation,and the acceptable performance rates of only 3 EQA items were 100％,i.e.,HbA2,urine microalbumin,and non-invasive prenatal testing(NIPT).Thir-ty-six analytes exhibited acceptable performance rate above of 80％,while that of troponin I was below 80％.Conclusion The medical laboratories in China should further increase their test covered by an EQA control rate and acceptable performance rate of EQA pro-gram,and consistantly improve testing quality by utilizing EQA programs adequately.

Objective:To investigate the current status of preimplantation genetic testing for aneuploidies (PGT-A) in China in 2024 and to provide recommendations for ensuring the consistency of PGT-A results.Methods:This study was a nationwide external quality assessment research. The National Center for Clinical Laboratories of the National Health Commission conducted two surveys in June and December 2024, with participation from 31 laboratories across China. During each survey, quality control samples of varying concentrations were distributed: the first survey distributed 6 samples (Batch Nos. 202401-202406) and the second survey distributed 3 samples (Batch Nos. 202431-202433). Participating laboratories were required to submit information including detection platforms, single-cell amplification methods, library construction methods, sequencing instruments, and test results. Collected data were statistically analyzed using Microsoft Excel to evaluate laboratories' PGT-A testing capabilities and determine whether results met predefined quality control requirements.Results:All 31 laboratories submitted results for both surveys. In the first survey, 90.3% (28/31) met qualification criteria with a 9.7% failure rate (3/31). For individual batches, pass rates were 90.3% (28/31) for batches 202401-202403 and 100% (31/31) for batches 202404-202406. The second survey achieved 100% (31/31) compliance across all three batches (202431-202433), with each batch maintaining a 100% pass rate.Conclusion:The detection quality of PGT-A in China is generally good, but with differences, and factors such as sample concentration, transportation conditions and detection methods affect the consistency of the results. The study highlights the urgent need for nationwide external quality assessment of PGT-A in China. This will help identify issues in laboratories in a timely manner and ensure the consistency of PGT-A test results.

Objective:To investigate the current status of preimplantation genetic testing for aneuploidies (PGT-A) in China in 2024 and to provide recommendations for ensuring the consistency of PGT-A results.Methods:This study was a nationwide external quality assessment research. The National Center for Clinical Laboratories of the National Health Commission conducted two surveys in June and December 2024, with participation from 31 laboratories across China. During each survey, quality control samples of varying concentrations were distributed: the first survey distributed 6 samples (Batch Nos. 202401-202406) and the second survey distributed 3 samples (Batch Nos. 202431-202433). Participating laboratories were required to submit information including detection platforms, single-cell amplification methods, library construction methods, sequencing instruments, and test results. Collected data were statistically analyzed using Microsoft Excel to evaluate laboratories' PGT-A testing capabilities and determine whether results met predefined quality control requirements.Results:All 31 laboratories submitted results for both surveys. In the first survey, 90.3% (28/31) met qualification criteria with a 9.7% failure rate (3/31). For individual batches, pass rates were 90.3% (28/31) for batches 202401-202403 and 100% (31/31) for batches 202404-202406. The second survey achieved 100% (31/31) compliance across all three batches (202431-202433), with each batch maintaining a 100% pass rate.Conclusion:The detection quality of PGT-A in China is generally good, but with differences, and factors such as sample concentration, transportation conditions and detection methods affect the consistency of the results. The study highlights the urgent need for nationwide external quality assessment of PGT-A in China. This will help identify issues in laboratories in a timely manner and ensure the consistency of PGT-A test results.

Objective:To analyze the quality level of maternal mid-trimester serum prenatal screening in China from 2019 to 2023.Methods:A questionnaire survey was conducted to collect information from laboratories participating in the National Health Commission′s Clinical Laboratory Center inter-laboratory quality assessment program for prenatal screening from 2019 to 2023. The collected data included screening protocols, detection methods, testing systems, and monthly laboratory screening quality indicators. The Chi-square test was used to compare the initial screening positive rates among different screening protocols, provinces, detection methods, and testing systems. A log-transformed linear regression analysis was performed to evaluate the relationship between the average annual sample size and the out-of-control rate of various median multiple of the median (mMoM) values.Results:This study included 806 laboratories from 29 provinces (including autonomous regions and municipalities). The five-year average out-of-control rates for mMoM values across indicators ranged from 15.8% to 31.3%. The initial positive rates of dual, triple, and quadruple screening protocols were statistically different ( χ2=760.2, P<0.001). The initial positive rates across different provinces ranged from 4.7% to 10.3%, with statistically significant differences ( χ2=35 388.0, P<0.001). There were also statistically significant differences in initial positive rates between different testing systems ( χ2=2 493.2, P<0.001). Testing systems using chemiluminescence methods had significantly higher initial positive rates compared to systems using time-resolved fluorescence methods (7.2% vs. 6.5%, χ2=533.6, P<0.001). Log-linear regression analysis showed that testing systems with larger annual average sample sizes had lower out-of-control rates for mMoM values (AFP: β=-0.100, P=0.005; hCG: β=-0.123, P=0.008; uE3: β=-0.139, P=0.007). Conclusion:There are significant differences in the quality of maternal mid-trimester serum screening across different detection methods, testing systems and provinces in China.

Objective To understand the status of medical laboratories participating in external quality assessment(EQA)program in China.Methods The test covered by an EQA control rate and acceptable performance rate of theinformation collection and data analy-sis systems in the EQA program developed by National Center for Clinical Laboratories in medical laboratories of nationwide various re-gions were evaluated descriptively and analyzed statistically.Forty analytes in various disciplines were selected to analyze statistically the implementation of the testing items and participation retes of EQA program.Results The number of medical laboratories participat-ing in EQA program increased yearly from 592 in 2019 to 1 169 in 2023.The nationwide median test covered by an EQA control rate and acceptable performance rate of EQA program reached over 91％and 98％,respectively.In 2023,the median test covered by an EQA control rate of EQA program in the medical laboratories of nationwide regions showed that the median test covered by an EQA con-trol rate reached 100％in Gansu and Hainan regions,and the medians of acceptable performance rate reached 100％in Beijing,Guangdong,Hubei,Jiangsu,Shandong,Shanxi,Shanghai,Tianjin,Xinjiang,and Zhejiang regions.Among the 40 analytes,the test covered by an EQA control rate of only 6 EQA items were greater than 80％in nationwide medical laboratories,i.e.,rheumatoid factor,neonatal deafness gene detection,high throughput sequencing of peripheral fetal chromosome aneuploidy(T21,T18 and T13)by high throughput sequencing,thalassemia gene typing,hepatitis C virus RNA quantification,and EGFR gene mutation,and the acceptable performance rates of only 3 EQA items were 100％,i.e.,HbA2,urine microalbumin,and non-invasive prenatal testing(NIPT).Thir-ty-six analytes exhibited acceptable performance rate above of 80％,while that of troponin I was below 80％.Conclusion The medical laboratories in China should further increase their test covered by an EQA control rate and acceptable performance rate of EQA pro-gram,and consistantly improve testing quality by utilizing EQA programs adequately.