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published before September 2024 in CNKI,PubMed,and Web of Science databases.Articles with poor relevance to the topic,outdated,or duplicated content were excluded,and finally,109 articles were included for review.RESULTS AND CONCLUSION:(1)This paper reviews recent methods for isolating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.

ObjectiveTo investigate the relationship between the vasodilation and hydrogen sulfide （H₂S） mechanism of total flavonoids of chrysanthemum （TFCC） and the large conductance Ca²⁺- activated K⁺ （BK_Ca） channels on vascular smooth muscle cells （VSMCs） of the middle cerebral artery in rats. In addition， this study will also investigate the effect of TFCC on the expression of BK_Ca channel alpha protein in rat middle cerebral artery VSMCs. MethodsThe primary method employed was acute digestion to isolate VSMCs from the middle cerebral artery of rats； whole-cell patch-clamp techniques were used to measure BK_Ca channel currents； primary tissue adherence culture was utilized to cultivate VSMCs from the middle cerebral artery of rats； Western blot were employed to determine protein expression levels. ResultsIn whole-cell patch-clamp experiments， both the H₂S donor NaHS （100 μmol/L） and endogenous H₂S enhanced BK_Ca channel currents. TFCC （30， 90， and 270 mg/L） also activatedBK_Ca channels and exhibited a certain concentration-dependent effect. Even after blocking endogenous H₂S production， TFCC （270 mg/L） still activated BK_Ca channels in VSMCs of the middle cerebral artery in rats. In Western blot experiments， the α-subunit of BK_Ca channel proteins was expressed in all groups of cells， but TFCC （30， 90， and 270 mg/L） and inhibitor IBTX group did not affect the expression of channel protein content.Conclusion TFCC can promote the opening of BK_Ca channels by promoting the generation of endogenous H₂S， or directly activate BK_Ca channels， thereby playing a role in relaxing cerebral blood vessels. However， TFCC had no significant effect on the expression of BK_Ca channel proteins.

Background: Malignant vasovagal syncope (VVS) is characterized by cardiac arrest lasting more than 3 seconds during a syncope episode or head-up tilt test (HUTT). We aim to conduct a risk assessment for potential malignant VVS before the HUTT by using economic, simple and convenient demographic data, in order to prevent adverse outcomes for pediatric VVS.Purpose: To explore the correlation between demographic factors and pediatric malignant VVS, and verify the value of these factors in early risk assessment for malignant VVS before HUTT, so as to optimize test safety and reduce adverse events. Methods: We conducted a retrospective analysis of the clinical data of 3,734 children who were initially diagnosed with VVS due to unexplained syncope and presyncope. Finally, 122 children who met the diagnostic criteria for malignant VVS were included in the malignant VVS group, and 661 children who did not meet the criteria during the same period were matched as the control group. By analyzing demographic data and other factors, we attempted to clarify the association between these factors and malignant VVS. Results: Linear relationship: age and body mass index (BMI) have independent protective effects on malignant VVS. For every 1-year increase in age and every 1 kg/m2 increase in BMI, the risk of malignant VVS decreases by 12% and 9%, respectively. Nonlinear relationship: When the age is <12.9 years old, for every additional year of age, the risk of malignant VVS decreases by 20%. For ages 12.9 years and above, the efficacy is not significant. There is no significant nonlinear relationship between BMI and malignant VVS. Conclusion Age and BMI are independent protective factors for pediatric malignant VVS. Before the age of 12.9 years, the incidence of malignant VVS gradually decreases with the increase in age, and thereafter there is no significant impact.

BackgroundThe mental health issues of medical staff have received increasing attention. Previous studies have mainly focused on the epidemiological characteristics and influencing factors， but there is a lack of sufficient understanding of the heterogeneity characteristics of the depression-anxiety symptoms network among medical staff. ObjectiveTo compare the differences in the depression-anxiety symptoms network between medical staff and community residents， so as to provide references for the promotion of the mental health of medical staff. MethodsFrom June 1， 2022 to December 31， 2024， a stratified random sampling method was used to recruit 1 959 medical staff from public hospitals and community health centers in 9 townships （industrial parks） of Dongguan City， Guangdong Province， as well as 2 412 community residents in this area， were selected as the research subjects. The general situation questionnaire， Patients' Health Questionnaire Depression Scale-9 item （PHQ-9）， and the Generalized Anxiety Disorder Scale-7 item （GAD-7） were used for investigation. The network visualization was conducted using the qgraph package of R 4.0.0. The centrality indicators of the network were calculated using the networktools package. The reliability of the network structure was evaluated using the bootnet package. The differences in the depression-anxiety symptoms network between medical staff and community residents were compared using the NetworkComparisionTest package. ResultsA total of 1 792 medical staff and 2 110 community residents completed the survey. The numbers of medical staff with mild， moderate and severe depressive symptoms were 381 （21.26%）， 217 （12.11%） and 169 （9.43%）， respectively， while the numbers of community residents were 322 （15.26%）， 98 （4.64%） and 66 （3.13%）， respectively. The numbers of medical staff with mild， moderate and severe anxiety symptoms were 411 （22.94%）， 126 （7.03%） and 93 （5.19%）， respectively， while the numbers of community residents were 320 （15.17%）， 73 （3.46%） and 18 （0.85%）， respectively. The comparison of the detection rates of depressive symptoms and anxiety symptoms between the two groups showed statistically significant differences （χ²=152.012， 205.953， P<0.01）. The network analysis results showed that the core symptom clusters of medical staff were "uncontrollable worry" "psychomotor retardation" "inability to relax"， and "depression"， while those of community residents were "uncontrollable worry" "inability to relax" "inferiority complex"， and "depression". There was a statistically significant difference in the network structure between the two groups （M=0.275， P<0.05）， and the overall connection strength of medical staff was lower than that of community residents （7.523 vs. 7.950， S=0.426， P<0.05）. ConclusionThe detection rates of depression and anxiety symptoms among medical staff were higher than those among community residents. The depression-anxiety symptoms network of medical staff was more concentrated， and the core symptoms were more prominent.［Funded by Social Development and Technology Project of Dongguan City （number， 20221800902552）］

ObjectiveThis study aims to develop a prediction model for the compatibility of Chinese medicinal pairs based on Graph Convolutional Networks （GCN）， named HC-GCN. The model integrates the properties of herbs with modern pharmacological mechanisms to predict pairs with specific therapeutic effects. It serves as a demonstration by applying the model to predict and validate the efficacy of blood-activating herb pairs. MethodsThe training dataset for herb pair prediction was constructed by systematically collecting commonly used herb pairs along with their characteristic data， including Qi， flavor， meridian tropism， and target genes. Integrating traditional characteristics of herb with modern bioinformatics， we developed an efficacy-oriented herb pair compatibility prediction model （HC-GCN） using graph convolutional networks （GCN）. This model leverages machine learning to capture the complex relationships in herb pair compatibility， weighted by efficacy features. The performance of the HC-GCN model was evaluated using accuracy （ACC）， recall， precision， F1 score （F1）， and area under the ROC curve （AUC）. Its predictive effectiveness was then compared to five other machine learning models： eXtreme Gradient Boosting （XGBoost）， logistic regression （LR）， Naive Bayes， K-nearest neighbor （KNN）， and support vector machine （SVM）. ResultsUsing herb pairs with blood-activating effects as a demonstration， a prediction model was constructed based on a foundational dataset of 46 blood-activating herb pairs， incorporating their Qi， flavor， meridian tropism， and target gene characteristics. The HC-GCN model outperforms other commonly used machine learning models in key performance metrics， including ACC， recall， precision， F1 score， and AUC. Through the predictive analysis of the HC-GCN model， 60 herb pairs with blood-activating effects were successfully identified. Among of these potential herb pairs， 44 include at least one herb with blood-activating effects. ConclusionIn this study， we established an efficacy-oriented compatibility prediction model for herb pairs based on GCN by integrating the unique characteristics of traditional herbs with modern pharmacological mechanisms. This model demonstrated high predictive performance， offering a novel approach for the intelligent screening and optimization of traditional Chinese medicine prescriptions， as well as their clinical applications.

Objective:To investigate the relationship between the single nucleotide polymorphisms (SNP) rs174575 and rs2845574 in the fatty acid desaturase 2 ( FADS2) gene and gestational diabetes mellitus (GDM). Methods:A total of 1 514 pregnant women who visited West China Second University Hospital, Sichuan University, between January 1, 2013, and December 31, 2021, were enrolled in this study. Among them, 583 were diagnosed with gestational diabetes mellitus (GDM group), and 931 had normal pregnancies (control group). The SNPs rs174575 and rs2845574 in the FADS2 gene were analyzed using Sanger DNA sequencing. Plasma levels, insulin (INS), apolipoprotein A1 (apoA1) and apolipoprotein B (apoB) levels were measured using enzymatic methods, chemiluminescence and immunoturbidimetry. This study was approved by Medical Ethics Committee of the West China Second University Hospital, Sichuan University (Ethics No. 2020-036). Results:① The main type of genotype at the rs174575 C/G and rs2845574 C/T polymorphic sites were CC in both GDM and control groups. No statistically significant differences were observed between the GDM and control groups regarding the genotype frequencies or allele frequencies of rs174575 and rs2845574 sites ( P>0.05). ② Among the GDM group, individuals with the GG genotype at the rs174575 site had lower plasma HDL-C levels compared to those with the CC genotype ( P<0.05), and had higher atherogenic indices (AI) than CC and CG genotype ( P<0.05; P<0.05). Individuals with the TT genotype at the rs2845574 site had higher AI than CT genotype ( P<0.05). Among the control group, individuals with the GG genotype had lower diastolic blood pressure (DBP) compared to those with the CC genotype ( P<0.05). ③ Additional subgroup analysis demonstrated that the rs174575 polymorphism was associated with AI levels in obesity subgroup of GDM, TG levels in non-obese subgroup of control and DBP levels in obese subgroup of control ( P<0.05; P<0.05; P<0.05). Conclusion:The FADS2 rs174575 and rs2845574 polymorphisms in GDM patients were associated wit HDL-C and AI levels, and the FADS2 rs174575 polymorphisms was also associated with DBP levels in normal pregnant women. The AI and DBP levels have BMI-dependent effect.

Osteoporosis and cardiovascular calcification,two major age-related chronic diseases that China is confronting today,pose serious threats to public health.Previous studies have reported overlapping connections in the pathological processes and molecular mechanisms of these two diseases,particularly concerning inflammation,oxidative stress,and dysregulation of mineral metabolism,and that these two diseases tend to share common pathogenic factors.However,research exploring the comorbidity mechanisms of the two diseases remains limited in both depth and scope,largely due to the lack of widely accepted comorbidity animal models.Herein,we analyzed the latest research findings on the comorbidity mechanisms of vascular calcification and osteoporosis,focusing on summarizing the animal disease models currently in extensive use and the relevant evaluation criteria.We aim to provide new references for comorbidity research models and offer scientific evidence for future studies on pathological mechanisms and the development of new therapeutic strategies.

Objective To investigate the predictive factors for postoperative gastrointestinal function in patients undergoing laparoscopic radical rectectomy(LRR),and thereby construct a predictive model.Methods A total of 155 patients who underwent LRR at our hospital from February 2021 to April 2024 were selected for this study.Based on the postoperative intake-nausea-vomiting-examination-duration of symptoms(I-FEED)scoring system,patients were divided into postoperative gastrointestinal dysfunction(POGD)and non-POGD groups.Clinical data of the selected patients were collected,and Logistic regression analysis was used to identify factors influencing the occurrence of POGD in LRR patients.A predictive model for POGD was constructed,and its predictive performance was evaluated using the receiver operating characteristic(ROC)curve.The calibration ability of the model was assessed using the H-L test.Results Of the 155 LRR patients,2 were excluded due to intraoperative conversion to open surgery and 1 due to insufficient data,resulting in a total of 152 patients included in the analysis.The incidence of POGD in these 152 patients was 33.55％(51/152).Logistic regression analysis identified age(OR=2.687,95％CI=1.422-5.078,P=0.003),smoking history(OR=2.564,95％CI=1.395-4.713,P=0.004),preoperative albumin(Alb)level(OR=0.851,95％CI=0.781-0.927,P＜0.001),dexmedetomidine combined with general anesthesia(OR=0.382,95％CI=0.214-0.682,P=0.001),the location of the abdominal auxiliary incision(OR=2.992,95％CI=1.278-7.006,P=0.007)and ligation location of inferior mesenteric artery(OR=3.784,95％CI=1.624-8.815,P=0.001)as influencing factors for POGD in LRR patients.The ROC curve showed that the predictive model constructed using these factors had an area under the curve(AUC)of 0.905,indicating good predictive performance.The H-L goodness-of-fit test showed no significant difference between the predicted and observed values(P＞0.05),indicating good calibration ability.Conclusion Age,smoking history,preoperative Alb level,dexmedetomidine combined with general anesthesia,the location of the abdominal auxiliary incision and ligation location of inferior mesenteric artery are influencing factors for POGD in LRR patients.The predictive model constructed based on these factors has good predictive value and calibration ability,providing a basis for targeted prevention and treatment to reduce the risk of POGD.

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.