BACKGROUND:Exosomes derived from mesenchymal stem cells play pivotal roles in cell communication and epigenetic regulation due to their low immunogenicity and targeted delivery effects,and have been clinically applied in the treatment of various diseases.OBJECTIVE:To review the isolation,purification,identification methods,and application progress of mesenchymal stem cell-derived exosomes,and to facilitate the development of large-scale preparation techniques and clinical translation of mesenchymal stem cell-derived exosomes.METHODS:The Chinese search terms"exosome,mesenchymal stem cells,isolation,purification,characterization,clinical application"and the English search terms"exosome,extracellular vesicles,mesenchymal stem cells,isolation,characterization,application"were used to search the literature published before September 2024 in CNKI,PubMed,and Web of Science databases.Articles with poor relevance to the topic,outdated,or duplicated content were excluded,and finally,109 articles were included for review.RESULTS AND CONCLUSION:(1)This paper reviews recent methods for isolating and purifying exosomes,comparing the characteristics of ultracentrifugation,ultrafiltration,size-exclusion chromatography,polymer precipitation,immunoaffinity,microfluidic methods,and other novel approaches based on their underlying principles.(2)Methods for identifying exosomes can be categorized into physical and biochemical analyses,characterizing exosomes based on their shape,size,and characteristic proteins.(3)Mesenchymal stem cell-derived exosomes have broad applications in multiple fields such as medical aesthetics,wound repair,and cancer treatment,due to their immune-regulatory properties and ability to cross biological barriers.(4)The clinical translation of exosomes faces challenges due to their complex structure,lack of universal isolation techniques,and poor stability,making it difficult to achieve in a short period of time.

BACKGROUND:Exosomes derived from mesenchymal stem cells play pivotal roles in cell communication and epigenetic regulation due to their low immunogenicity and targeted delivery effects,and have been clinically applied in the treatment of various diseases.OBJECTIVE:To review the isolation,purification,identification methods,and application progress of mesenchymal stem cell-derived exosomes,and to facilitate the development of large-scale preparation techniques and clinical translation of mesenchymal stem cell-derived exosomes.METHODS:The Chinese search terms"exosome,mesenchymal stem cells,isolation,purification,characterization,clinical application"and the English search terms"exosome,extracellular vesicles,mesenchymal stem cells,isolation,characterization,application"were used to search the literature published before September 2024 in CNKI,PubMed,and Web of Science databases.Articles with poor relevance to the topic,outdated,or duplicated content were excluded,and finally,109 articles were included for review.RESULTS AND CONCLUSION:(1)This paper reviews recent methods for isolating and purifying exosomes,comparing the characteristics of ultracentrifugation,ultrafiltration,size-exclusion chromatography,polymer precipitation,immunoaffinity,microfluidic methods,and other novel approaches based on their underlying principles.(2)Methods for identifying exosomes can be categorized into physical and biochemical analyses,characterizing exosomes based on their shape,size,and characteristic proteins.(3)Mesenchymal stem cell-derived exosomes have broad applications in multiple fields such as medical aesthetics,wound repair,and cancer treatment,due to their immune-regulatory properties and ability to cross biological barriers.(4)The clinical translation of exosomes faces challenges due to their complex structure,lack of universal isolation techniques,and poor stability,making it difficult to achieve in a short period of time.

Ischemic stroke (IS) is a globally life-threatening disease. Presently, few therapeutic medicines are available for treating IS, and rt-PA is the only drug approved by the US Food and Drug Administration (FDA) in the US. In fact, many agents showing excellent neuroprotection but no blood flow-improving activity in animals have not achieved ideal clinical efficacy, while thrombolytic drugs only improving blood flow without neuroprotection have limited their wider application. To address these challenges and meet the huge unmet clinical need, we have designed and identified a novel compound AAPB with dual effects of neuroprotection and cerebral blood flow improvement. AAPB significantly reduced cerebral infarction and neural function deficit in tMCAO rats, pMCAO rats, and IS rhesus monkeys, as well as displayed exceptional safety profiles and excellent pharmacokinetic properties in rats and dogs. AAPB has now entered phase I of clinical trials fighting IS in China.

Glycosylation plays an important role in tumorigenesis and development. Mucoprotein-1 (MUC1), a transmembrane glycoprotein, is overexpressed in a variety of malignant tumors. The biochemical characteristics of tumor-specific short chain O-glycosylation (such as Tn/sialyl Tn (STn) antigens) are significantly different from those of normal tissue MUC1, which provides a molecular basis for precision diagnosis and treatment of tumors. This article systematically reviews the molecular design, clinical transformation progress and technical bottleneck of three types of probes targeting MUC1 glycosylation epitopes in tumors, including aptamers, peptides and monoclonal antibodies, focusing on their tumor uptake efficiency, targeting specificity and the potential of diagnosis and treatment integration, so as to provide theoretical basis for optimizing the clinical transformation path of MUC1 targeting probes.

Objective:To analyze the clinical characteristics and gene mutations of 4 patients with the male phenotype of 17α-hydroxylase /17, 20-lyase deficiency(17-OHD), in order to improve the recognition and appropriate management of atypical cases.Methods:A retrospective analysis was performed on the clinical features, biochemical findings, and gene mutations of 4 patients with the male phenotype of 17-OHD treated in our hospital between 2018 and 2023.Results:The social gender of all 4 patients with 17-OHD was male. None of the 4 patients had hypertension or hypokalemia, but all had micropenis and gynecomastia. Two patients had adrenal hyperplasia, while adrenal morphology was normal in the other two. One patient had decreased bone mass. There were typical changes in the steroid synthesis-related hormone spectrum: progesterone was significantly elevated in all 4 patients, 17-hydroxyprogesterone was not markedly abnormal, cortisol, dehydroepiandrosterone sulfate(DHEAS) and estradiol levels were low, and testosterone levels were also low.Conclusion:17-OHD is a rare type of congenital adrenal hyperplasia, with the male phenotype being even rarer. Early symptoms are often atypical, resulting in high rates of misdiagnosis and missed diagnosis. Patients without hypertension and hypokalemia are particularly prone to diagnostic confusion. Male patients with unexplained progesterone elevation, poor secondary sexual development, and gynecomastia should undergo timely steroid hormone profiling and genetic testing to avoid misdiagnosis and missed diagnosis.

Objective To establish a ultrahigh-performance liquid chromatography-orbitrap high-resolution mass spectrometry(UHPLC-Orbitrap HRMS)method for the determination of the genotoxic impurity N-nitroso propranolol(NPPN)in propranolol hydrochloride sustained-release tablets.Methods The test sample was ultrasonically extracted using methanol as the solvent,then centrifuged and filtered before injection analysis.Chromatographic separation was performed using a 2.7 μm particle size C18 UHPLC column with a mobile phase of 0.1％formic acid(A)in water and 0.1％formic acid(B)in acetonitrile,using gradient elution.Mass spectrometry was conducted with an HESI ion source in positive ion parallel reaction monitoring(PRM)scan mode,monitoring the NPPN fragment ion at m/z 72.080 8,and quantification was performed using the standard curve method.Results The calibration curve was in good linearity in the range of 0.51-20.30 ng·mL-1 with excellent correlation coefficient(r)of 0.9999.The recoveries of NPPN at three levels(low,medium,and high)were in the range of 95.4％～98.3％,while the RSDs were from 2.5％to 4.2％.The limit of detection(LOD)was 0.20 ng·mL-1 while the limit of quantitfication(LOQ)was 0.51 ng·mL-1.This analytical method was used to determine NPPN in six batches of propranolol hydrochloride sustained release tablet samples.NPPN was detected in all six samples,among which the detection amount of 3 batches have exceeded the acceptable limit.Conclusion This method is sensitive,accurate,and fast,making it useful for pharmaceutical companies in controlling production processes and providing robust technical support for regulatory authorities.

Objective:To evaluate the feasibility of using the domestic ArcherQA system for fast and simplified independent verification of CyberKnife (CK) stereotactic radiotherapy (SRT) plans.Methods:SRT plans of 57 patients treated with CK at Tianjin Medical University Cancer Institute and Hospital from August 2021 to August 2022 were retrospectively analyzed, including 15 intracranial, 30 pulmonary, and 12 abdominal tumors cases. Point-dose and planar-dose verifications were performed using an ionization chamber and radiochromic films embedded in a homogeneous phantom, and the results were compared with those calculated by the treatment planning system (TPS). The localization CT images and corresponding SRT plans were imported into the ArcherQA system for independent dose verification and analysis. The correlation between ArcherQA results and phantom measurements was analyzed, with comparisons of target mean dose differences and γ pass rates.Results:Phantom measurement results showed, the measured point-dose differences for intracranial, lung, and abdominal plans were -0.94% ± 3.22%, 1.92% ± 2.05%, and 2.12% ± 0.77%, respectively. The mean dose differences in target dose calculation between ArcherQA and TPS: intracranial in the gross tumor volume (GTV) regions were 0.34% ± 2.21%, lung tumor GTV were -2.47% ± 2.46%, and abdominal tumor GTV were 0.80% ± 2.61%, respectively. Among them, the abdominal GTV region showed the highest correlation between ArcherQA and measured results ( r=0.78). The average two-dimensional γ pass rates (2 mm/2%, threshold=10%) measured using phantom films were 95.92% ± 2.35% for intracranial, 95.70% ± 2.74% for lung, and 96.74% ± 3.41% for abdominal tumors plans, respectively. The three-dimensional ArcherQA results showed comparable γ pass rates (1 mm/2%, threshold=10%) for lung and abdominal GTV and PTV regions, with similar medians and data dispersion to film measurements. Conclusions:The ArcherQA system enables rapid and efficient independent dose verification of CK SRT plans without the need for additional hardware. The verification results show good correlation with phantom measurements, supporting its potential as an auxiliary quality assurance tool in clinical CK SRT implementation.

Objective:To investigate the expressions of cystathionine-β-synthase(CBS)and cystathionine-γ-lyase(CSE)and their effects on the malignant biological behaviours of breast cancer cells,and to elucidate their mechanisms.Methods:The breast cancer tissue and paracancerous normal tissue from 15 cases of patients were selected,and RT-qPCR and Western blotting methods were used to detect the mRNA and protein expression levels of CBS and CSE in breast cancer tissue,paracancerous normal tissue,MCF-7 cells,and MDA-MB-231 cells.The MCF-7 cells were divided into siNC group(transfected with siNC)and siCBS group(transfected with siCBS),and the MDA-MB-231 cells were divided into ovNC group(transfected with CSE over-expression empty plasmid)and ovCSE group(transfected with CSE over-expression plasmid).CCK8 assay was used to detect the proliferation activities of breast cancer cells in various groups,Transwell assay was used to detect the numbers of migration and invasion cells in various groups,and Western blotting method was used to detect the protein expression levels of E-cadherin,N-cadherin and Vimentin proteins in the breast cancer cells in various groups.Results:Compared with paracancerous normal tissue,the expression levels of CBS and CSE mRNA and proteins in breast cancer tissue were increased(P＜0.05 or P＜0.01).Compared with MDA-MB-231 cells,the CBS mRNA expression level in the MCF-7 cells was increased(P＜0.05);compared with MCF-7 cells,the expression level of CSE protein in the MDA-MB-231 cells was decreased(P＜0.05).Compared with siNC group,the proliferation activity,the numbers of migration and invasion cells,the expression levels of N-cadherin and Vimentin proteins in the MCF-7 cells in siCBS group were significantly decreased(P＜0.05),and the expression level of E-cadherin protein was increased(P＜0.05).Compared with ovNC group,the proliferation activity,the numbers of migratoin and invasion cells,and the expression levels of N-cadherin and Vimentin proteins in the MDA-MB-231 cells in ovCSE group were increased(P＜0.05),while the expression level of E-cadherin protein was significantly decreased(P＜0.05).Conclusion:The expressions of CBS and CSE are upregulated in breast cancer tissue,and high levels of CBS and CSE promote proliferation,migration,invasion and epithelial-mesenchymal transition(EMT)of breast cancer cells.

Objective:To investigate the risk factors for esophageal varices in patients with liver cirrhosis,to establish a predictive model,and to provide reasonable guidance for the prevention of early esophageal varices in patients with liver cirrhosis.Methods:A retrospective analysis was performed for 1 113 patients with liver cirrhosis who attended the hospitals in Chongqing,China from Decem-ber 2006 to May 2021.Recursive feature elimination(RFE)and four machine learning methods were used for the screening of features,and five machine learning predictive models were established by logistic regression,random forest,support vector machine(SVM),de-cision tree,and eXtreme Gradient Boosting(XGBoost).The receiver operating characteristic(ROC)curve was used to evaluate the per-formance of each model,and the model with the best performance was used to investigate the risk factors for esophageal varices in pa-tients with liver cirrhosis.SHAP plots were used to explain the impact of each risk factor on patients.Results:The XGBoost model showed the best performance in predicting the risk of esophageal varices in patients with liver cirrhosis,with an area under the ROC curve of 0.872(95%CI=0.813-0.918).SHAP plots showed that platelet count,diameter of the portal vein,cholinesterase,albumin,ala-nine aminotransferase,hemoglobin,prothrombin ratio,prothrombin time,and serum total protein were risk factors for esophageal vari-ces in patients with liver cirrhosis.Conclusion:This study shows that the XGBoost predictive model has a relatively high predictive value,and the risk factors obtained by this model have a certain guiding significance for the clinical prevention and treatment of early esophageal varices in patients with liver cirrhosis.

Objective To investigate the effects of secukinumab combined with E'xian Huaban decoction on traditional Chinese medicine symptom scores and nailfold microcirculation morphology in patients with plaque psoriasis.Methods A total of 120 patients with plaque psoriasis were selected and randomly divided into monotherapy group(n=60)and combination therapy group(n=60).The monotherapy group received secukinumab treatment,while the combination therapy group was treated with secukinumab plus E'xian Huaban Decoction.Clinical therapeutic efficacy,traditional Chinese medicine symptom scores(including skin lesions,pruritus,rough skin,scales and irritabili-ty),relevant scale[Psoriasisarea and Severity Index(PASI),Dermatology Life Quality Index(DLQI)and Visual Analogue Scale(VAS)]scores,inflammatory factors[interleukin-17(IL-17),interleukin-23(IL-23)and vascular endothelial growth factor(VEGF)]levels and nailfold microcircu-lation morphology(loop tube morphology,blood flow state and loop periphery state)were observed in both groups.Results The overall clinical efficacy rate in the combination therapy group was 95.00％,which was significantly higher than 83.33％ in the monotherapy group(P＜0.05).After treatment,traditional Chinese medicine symptom scores(skin lesions,pruritus,rough skin,scales and irritability),inflammatory factors(IL-17,IL-23 and VEGF)levels,scale(PASI,DLQI and VAS)scores as well as loop tube morphology scores,blood flow state scores and loop periphery state scores were signifi-cantly lower compared to pre-treatment values,and these parameters were significantly lower in the combination therapy group than the monotherapy group(P＜0.05).Conclusion Secukinumab combined with E'xian Huaban Decoction can significantly improve clinical symptoms and signs,and enhancing the clinical therapeutic effect.