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published before September 2024 in CNKI,PubMed,and Web of Science databases.Articles with poor relevance to the topic,outdated,or duplicated content were excluded,and finally,109 articles were included for review.RESULTS AND CONCLUSION:(1)This paper reviews recent methods for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

Guided by the concept of "onset due to compounding factors" from Inner Canon of Yellow Emperor （《黄帝内经》）， it is believed that the basic pathogenesis of radiation-induced intestinal injury is the depletion of the root and the invasion of external pathogenic fire and heat toxin. The deficiency induced by pre-existing pathogen has not been resolved， and the external invasion of a new pathogen， characterized by fire and heat toxin， has further aggravated the condition， leading to radiation-induced intestinal injury due to the interaction of internal and external factors. The treatment should focus on reinforcing healthy qi and expelling pathogen， performingtreatment with both attack and supplementation. The experience-based prescription Huchang Kangfu Decoction （护肠抗辐汤） should be used as the main formula， with treatment differentiated according to stages. During the acute stage， adjustments on medicinals should be made to supplement deficiency， clear heat， resolve toxin， and consolidate the intestines. During the chronic stage， medicinals that can warm the kidneys， tonify the spleen， nourish the blood， and soften the liver should be modified according to symptoms. Above methods provide a treatment approach for radiation-induced intestinal injury.

ObjectiveTo explore the mechanism of Sangpi Zhike prescription in treating cough after respiratory syncytial virus （RSV） infection through the "lung-intestine co-treatment" approach using network pharmacology and animal experimental validation. MethodsActive ingredients and targets of Sangpi Zhike prescription were retrieved from the Traditional Chinese Medicine Systems Pharmacology （TCMSP） database. Disease targets were obtained from GeneCards and Online Mendelian Inheritance in Man（OMIM） databases. Protein-protein interaction （PPI） networks and drug-component-target networks were constructed using overlapping targets between drugs and diseases to identify core targets. Gene ontology（GO） and Kyoto encyclopedia of genes and genomes（KEGG） pathway enrichment analyses were performed on the overlapping targets. Sixty mouse models were established： 10 as the normal group， and the remaining mice were infected with RSV via slow nasal drip of RSV suspension， with cough induced using capsaicin solution. After modeling， mice were divided into a model group， a Montelukast Sodium group （1 mg·kg^-1·d^-1）， and low， medium， and high dose groups of Sangpi Zhike prescription （4.875，9.75，and 19.5 g·kg^-1·d^-1）， with 10 mice per group. From day 14 after RSV infection， the normal and model groups received saline via gavage， while other groups received corresponding drug treatments once daily for 5 d. Hematoxylin-eosin（HE） staining was used to observe pathological changes in lung and intestinal tissue. The protein content of extracellular signal-regulated kinase 1/2 （ERK1/2） and phosphorylated （p）-ERK1/2 in the lung and colon tissue of mice was detected by Western blot. Real-time polymerase chain reaction（Real-time PCR） detected ERK1/2 mRNA expression in lung and intestinal tissue. Immunohistochemistry assessed p-MEK1/2， p-ERK1/2， p-c-Fos protein levels， and inflammatory cytokines interleukin（IL）-4 and （TNF）-α in lung and colon tissue. ResultsNetwork pharmacology identified 184 active ingredients and 684 targets in Sangpi Zhike prescription， with 1 344 RSV-related disease targets and 209 overlapping targets. Core targets included TNF， Fos， and Jun. KEGG enrichment revealed 179 pathways， primarily mitogen-activated protein kinase（MAPK）， cancer， TNF， and IL-17 signaling pathways. Animal experiments showed that， compared to those of the normal group， the lung tissue sections of the model group showed typical inflammatory damage， infiltration of inflammatory cells， rupture of alveolar septa， extensive alveolar fusion， and disruption of tight junctions between single-layer columnar epithelial cells in the intestinal tissue. The values of p-ERK1/2 and ERK1/2 in lung and intestinal tissue were significantly increased （P<0.01）， and the expression level of ERK1/2 mRNA was significantly elevated （P<0.01）. The levels of ERK1/2， p-MEK1/2， p-ERK1/2， p-c-Fos， IL-4， and TNF-α along the ERK pathway were significantly increased （P<0.05， P<0.01）. Compared to the model group， Sangpi Zhike prescription groups showed reduced lung and intestinal inflammation， decreased p-ERK1/2/ERK1/2 ratios （P<0.05，P<0.01）， lower ERK1/2 mRNA levels， and downregulated ERK pathway proteins （P<0.05，P<0.01）. ConclusionSangpi Zhike prescription alleviates cough and intestinal symptoms after RSV infection via the "lung-intestine co-treatment" mechanism by suppressing expression levels of ERK1/2， p-MEK1/2， p-ERK1/2， p-c-Fos， IL-4， and TNF-α on ERK pathway components， thereby mitigating lung and intestinal pathological damage.

ObjectiveThe exacerbating trend of global population aging poses profound socioeconomic and public health challenges, making the comprehensive elucidation of biological aging mechanisms and the discovery of effective anti-aging interventions an urgent priority in the life sciences. Based on our previous serum metabolomics findings that dimethylglycine, an intermediate metabolite of amino acid metabolism naturally present in the human body, was significantly enriched in the serum of longevity families, this study aimed to systematically investigate the anti-aging effects of dimethylglycine both in living organisms and in controlled laboratory environments, and to preliminarily elucidate its underlying molecular mechanisms. While existing literature indicates that dimethylglycine possesses antioxidant and immunomodulatory properties, its direct anti-aging efficacy and the specific molecular pathways through which it operates remain largely unexplored. MethodsTo comprehensively evaluate the anti-aging properties of dimethylglycine, we utilized replicative senescent human embryonic lung fibroblasts, specifically the WI-38 cell line, as an experimental model in a controlled laboratory environment. Cell viability and safety were thoroughly assessed using Cell Counting Kit-8 and lactate dehydrogenase release assays across various concentrations of dimethylglycine. The impact of dimethylglycine on cellular senescence phenotypes, oxidative stress, and proliferative capacity was evaluated via senescence-associated beta-galactosidase staining, reactive oxygen species fluorescence detection, and 5-ethynyl-2'-deoxyuridine incorporation assays. Furthermore, the molecular alterations of senescence-associated secretory phenotype factors and core senescence signaling pathways were quantified using quantitative reverse transcription polymerase chain reaction for the messenger RNA levels of interleukin-6, interleukin-8, p21, and matrix metalloproteinase-1, and enzyme-linked immunosorbent assay for the measurement of p16 and p21 protein expression levels. For the living organism model, the wild-type nematode Caenorhabditis elegans was used to evaluate systemic physiological effects. We conducted a comprehensive lifespan analysis at 20°C, heat stress resistance survival assays at 35℃, senescence-associated beta-galactosidase staining, lipofuscin accumulation tracking, intracellular reactive oxygen species measurement, and Oil Red O staining to ascertain systemic lipid accumulation. Additionally, network pharmacology bioinformatics tools, including PharmMapper and STRING databases, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were utilized to predict target pathways, alongside highly detailed molecular docking simulations utilizing SwissDock and Protein-Ligand Interaction Profiler to examine interactions with the cytochrome P450 family 2 subfamily C member 9 protein. ResultsThe experimental outcomes robustly demonstrate the potent anti-aging capabilities of dimethylglycine. At the cellular level, toxicity analyses firmly confirmed that dimethylglycine is highly safe; continuous treatment with 50 mol/L and 70 mol/L of dimethylglycine for 5 d did not induce any cellular membrane damage or cytotoxicity, but rather actively promoted cellular proliferation. Utilizing the optimal standardized concentration of 50 mol/L, dimethylglycine treatment significantly ameliorated senescent phenotypic markers in human embryonic lung fibroblasts, which was evidenced by a drastic and highly significant reduction in the senescence-associated beta-galactosidase positive cell percentage (P<0.000 1) and intracellular reactive oxygen species levels (P<0.000 1), alongside a marked increase in the 5-ethynyl-2'-deoxyuridine-positive proliferation rate (P=0.003 5). On a molecular expression scale, dimethylglycine significantly downregulated the messenger RNA expression of multiple core senescence-associated secretory phenotype inflammatory factors, including interleukin-6, interleukin-8, p21, and matrix metalloproteinase-1. Concurrently, it effectively suppressed the protein expression of critical cell cycle arrest markers, diminishing p16 protein levels by 57.3% (P=0.000 4) and p21 protein levels by 27.2% (P=0.000 7). In the nematode Caenorhabditis elegans animal model, dimethylglycine significantly extended the mean lifespan from 20.402 d to an impressive 23.066 d (P<0.000 1) and notably enhanced overall survival rates under severe heat stress environmental conditions (P=0.017). Furthermore, systemic dimethylglycine intervention significantly mitigated age-related physiological decline by decreasing bodily lipofuscin accumulation (P<0.000 1), significantly reducing senescence-associated beta-galactosidase activity, lowering systemic reactive oxygen species fluorescence (P=0.008), and effectively alleviating overall fat accumulation (P<0.000 1). Mechanistically, extensive network pharmacology and Kyoto Encyclopedia of Genes and Genomes analyses strongly revealed that the potential targets of dimethylglycine are significantly enriched in fundamental drug metabolism and oxidative stress response pathways. Precision molecular docking simulations conclusively demonstrated that dimethylglycine forms highly stable structural interactions with the cytochrome P450 family 2 subfamily C member 9 protein, specifically highlighting the definitive formation of 5 stable hydrogen bonds involving serine 365, leucine 366, and serine 429 residues, as well as two critical salt bridge formations with arginine 97 and histidine 368 residues. It is additionally predicted to interact favorably with glutathione S-transferase family proteins. ConclusionDimethylglycine exhibits a profoundly significant and multifaceted anti-aging activity at both the cellular and entire living animal levels. By powerfully alleviating oxidative stress, heavily suppressing the core p16 and p21-dependent cellular senescence signaling pathways, and substantially mitigating the detrimental senescence-associated secretory phenotype, dimethylglycine effectively delays fundamental cellular senescence processes and drastically extends whole-organism lifespan. The biological mechanisms driving these robust protective effects are highly likely closely associated with its direct stable interactions with crucial metabolic and detoxifying enzyme systems, such as cytochrome P450 family 2 subfamily C member 9 and glutathione S-transferase family proteins, thereby systemically improving metabolic dysregulation and restoring critical redox homeostasis. This comprehensive study provides highly solid experimental evidence supporting dimethylglycine as a highly potent and safe potential anti-aging intervention agent, while simultaneously offering a clear molecular mechanistic explanation for the previously documented high abundance of dimethylglycine observed within exceptionally long-lived human populations.

ObjectiveTo investigate the prevalence of muscle changes （including sarcopenia and myosteatosis） and related influencing factors in patients with porto-sinusoidal vascular disorder （PSVD）， and to provide a theoretical basis for the early identification， prevention， and intervention of muscle changes in PSVD patients. MethodsA total of 132 PSVD patients who were diagnosed in Nanjing Second Hospital from July 2017 to July 2024 were enrolled as case group， and the hospital staff who underwent physical examination in 2025 were enrolled as healthy control group. Propensity score matching was performed based on age and sex at a ratio of 1∶1. According to muscle status assessed by abdominal CT， the subjects were divided into non-muscle change group， mild muscle change group （myosteatosis alone）， and severe muscle change group （sarcopenia alone or sarcopenia comorbid with myosteatosis）， with the type and severity of muscle change as the exposure factors. General information， laboratory tests， L3-level CT images， and liver biopsy data were collected for the patients in the case group， and general information and CT images were collected for the individuals in the healthy control group. Sarcopenia was diagnosed by measuring skeletal muscle index at the L3 level （<44.77 cm²/m² for men and <32.50 cm²/m² for women）， and myosteatosis was defined by mean muscle attenuation combined with BMI （BMI <24.9 kg/m² with attenuation <41 HU or BMI ≥25 kg/m² with attenuation <33 HU）. Demographic， laboratory， and clinical parameters were compared between the case group and the healthy control group. The independent-samples t test was used for comparison of normally distributed continuous data between groups， and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between groups； the chi-square test or the Fisher’s exact test was used for comparison of categorical data between groups. The univariate and multivariate Logistic regression analyses were used to identify the factors associated with sarcopenia in PSVD. ResultsAmong the 132 patients with PSVD， there were 83 patients with portal hypertension （PH） and 49 patients without PH， and there were significant differences between these two groups in age， albumin， albumin/globulin ratio， leukocyte count， neutrophil count， red blood cell count， platelet count， direct bilirubin， indirect bilirubin， hemoglobin， blood calcium， cholinesterase， total bile acid， triglyceride， total cholesterol， prothrombin time， international normalized ratio， activated partial thromboplastin time， decompensation， gastroesophageal or ectopic varices， bleeding and ascites （all P<0.05）. The analyses after matching showed that compared with the healthy control group， the case group had significantly higher prevalence rates of abnormal muscle structure （43.18% vs 18.94%， P<0.001）， mild muscle changes （22.73% vs 7.58%， P<0.001）， and severe muscle changes （20.45% vs 11.36%， P<0.001）. Further comparison showed that there was no significant difference in the proportion of patients with muscle changes between the PSVD patients with PH and those without PH （42.17% vs 44.90%， P=0.760）. The binary Logistic regression analysis with the presence or absence of muscle changes as the dependent variable showed that age （odds ratio ［OR］=1.05， 95% confidence interval ［CI］： 1.02 — 1.09， P<0.05）， subcutaneous fat index （OR=1.03， 95%CI： 1.01 — 1.06， P<0.05）， hemoglobin （OR=0.97， 95%CI： 0.95 — 0.99， P<0.05）， and thrombin time （OR=1.26， 95%CI： 1.06 — 1.49， P<0.05） were independent influencing factors for muscle changes in PSVD patients. The multivariate ordinal Logistic regression analysis with the severity of muscle changes as the dependent variable showed that age （OR=1.04， 95%CI： 1.01 — 1.07， P<0.05） and thrombin time （OR=1.17， 95%CI： 1.01 — 1.36， P<0.05） were independent risk factors for the grading of muscle changes. ConclusionMuscle changes are common in PSVD patients， and these changes may be caused by PSVD itself rather than PH. Age， fat distribution， thrombin time， and hemoglobin are important influencing factors for muscle changes.

Objective In order to understand the current resistance status of Aedes albopictus(Ae. albopictus) adult population to commonly used insecticides and the resistance dynamics development in Zhejiang Province and provide a theoretical basis for the scientific and rational use of hygienic insecticides. Methods Resistance determination was carried out using the diagnostic dose method(GB/T 26347-2010)recommended by WHO in the adult mosquito contact cylinder method to monitor the resistance of Ae. albopictus field populations in 11 cities and districts in Zhejiang Province in 2024. Results The monitoring result showed that adult Ae. albopictus in 11 areas were resistant or suspected resistant populations to both cis-cypermethrin and permethrin; suspected and resistant populations to the organophosphate insecticide malathion were as high as 81.82%; while suspected resistance to the carbamate insecticide residual carbofuran accounted for 45.45%, and the rest of the monitoring sites were sensitive to it. Conclusions The result suggest that the generalized resistance of Ae. albopictus populations to pyrethroids and organophosphorus insecticides in the field in Zhejiang Province needs to be highly emphasized. In future mosquito vector and mosquito-borne disease control, insecticides should be selected based on the resistance monitoring information, while following scientific guidelines for insecticide use.

Objective To explore latent classes of behavioural and psychological symptoms in the patients with Alzheimer's disease(AD)and to identify the factors influencing the latent classes and provide a basis for fomulating personalized nursing measures.Methods Convenience sampling was employed to recruit 361 AD inpatients from our hospital between November 2023 and May 2024 for this cross-sectional study.A general data questionnaire,the neuropsychiatric inventory questionnaire,Monteria cognitive assessment scale,activity of daily life scale,and mini-nutritional assessment scale were used in the survey.Latent class analysis was conducted to analyse the data acquired from the survey.Univariate analysis and multiple Logistic regression analysis were used to identify the factors influencing latent classes.Results Toally 346 patients finished the study.It was found that a 72.5%of AD patients developed behavioural and psychological symptoms.The symptoms were categorised into three classes:low symptom-apathy,middle symptom-emotional disturbance and high symptom-behaviour disorder.The course of disease,cognitive function,daily living ability and nutritional status were identified as the factors that influenced the latent classes(all P<0.05).Conclusion AD patients with low cognitive function,poor daily living ability,malnutrition and a course of disease over 5 years are at high risks of behavioural and psychological symptoms which are heterogeneous.Care providers are advised to propose personalised care strategies to improve the behavioural and psychological symptoms.

Objective:To analyze the effect of migration experiences during working age on the status of chronic disease development among rural older adults.Methods:Based on data from the China Health and Retirement Longitudinal Study(CHARLS),this study applied regression model and group-based trajectory model to examines the impact of migration experience on the status and growth trajectories of chronic diseases among rural older adults.Results:(1)Rural older adults with migration experience are more likely to develop chronic diseases and have a greater number of chronic disease in later life.(2)Rural older adults with migration experiences have a higher starting point and a faster rate of growth trajectory of chronic disease.Suggestions:It is necessary to strengthen occupational protection and health education for the rural-urban migrant population,reinforce the intervention and management of chronic diseases for the returning population,and improve the whole life-cycle medical insurance system,to break the disadvantageous cumulative effect of migration experience on health.

OBJECTIVE To understand the disinfectant-resistant genes in the gram-negative bacteria isolated from the dirt retention on air recure filters of air conditioners and observe the drug resistance.METHODS The dirt re-tention samples were collected from the air return filters of air conditioners of some wards in 3 hospitals of Wuhan(Tongji Hospital of Tongji Medical College of Huazhong University of Science and Technology,Wuhan Central Hospital,and Hubei Provincial Maternal and Child Health Hospital)from 2018 to 2024.The gram-negative bac-teria were screened out,the disinfectant-resistant genes in the strains were detected by polymerase chain reaction(PCR),and the results of drug susceptibility test were analyzed.RESULTS Of 354 dirt retention samples that were collected from the air return filers of air conditioners,77 were detected with 138 strains of gram-negative bacteria,87 of which were Acinetobacter baumannii,50 were Enterobacteriaceae,and 1 was Pseudomonas aerug-inosa.The detection rates of qacEΔ1,qacEΔ1-sul1,aceI and qacA/B were 73.19％,82.61％,69.57％and 2.90％,respectively.None of the strains were detected with qacC,qacH or qacJ.The result of drug susceptibility test showed that 76.81％of the gram-negative bacteria were resistant to at least 1 type of antibiotic;93 strains of multidrug-resistant gram-negative bacteria were isolated,most of which were isolated from intensive care unit(ICU).The detection rates of qacEΔ1 and qacEΔ1-sul1 were higher in the drug-resistant strains than those in the non-drug-resistant strains;there were significant differences in the drug resistance rates to carbapenems,quin-olones and β-lactams between the qacEΔ1-sul 1-positive strains and the qacEΔ1-sul1-negative strains(P＜0.05).CONCLUSIONS There are drug-resistant gram-negative bacteria contaminations in some wards of the 3 hospitals in Wuhan.The carrying rates of disinfectant-resistant genes of the strains are high,and the strains show varying degree of resistance to the commonly used antibiotics;the strains carrying the qacEΔ1-sul1 have certain statistical association with the drug resistance.It is suggested that the hospital should take targeted disinfec-tion measures for the environment and reasonably use antibiotics.