ObjectiveTo investigate the influence of entecavir （ETV） versus tenofovir alafenamide fumarate （TAF） on renal function in previously untreated patients with chronic hepatitis B （CHB）. MethodsA retrospective analysis was performed for the clinical data of 167 previously untreated CHB patients who received ETV or TAF treatment for at least 48 weeks at the outpatient service of Department of Infectious Diseases in The First Affiliated Hospital of Nanchang University from September 2019 to November 2023， and according to the antiviral drug used， they were divided into ETV group with 117 patients and TAF group with 50 patients. In order to balance baseline clinical data， propensity score matching （PSM） was used for matching and analysis at a ratio of 2∶1， and the two groups were compared in terms of estimated glomerular filtration rate （eGFR） and the incidence rate of abnormal renal function at week 48. According to eGFR at week 48， the patients were divided into normal renal function group and abnormal renal function group. The independent-samples t test or the Mann-Whitney U test was used for comparison of continuous data between two groups， and the chi-square test or the Fisher’s exact test was used for comparison of categorical data between two groups. The multivariate Logistic regression analysis was used to investigate the influencing factors for abnormal renal function， and the receiver operating characteristic （ROC） curve was used to assess the performance of each indicator in predicting abnormal renal function. The Kaplan-Meier method was used to analyze the cumulative incidence rate of abnormal renal function， and the log-rank test was used for comparison. The analysis of variance with repeated measures was used to compare the dynamic changes of eGFR during antiviral therapy in CHB patients. ResultsAfter PSM matching， there were 100 patients in the ETV group and 50 patients in the TAF group. There were no significant differences in baseline clinical data between the ETV group and the TAF group （all P>0.05）， with an eGFR level of 112.29±9.92 mL/min/1.73 m² in the ETV group and 114.72±12.15 mL/min/1.73 m² in the TAF group. There was a reduction in eGFR from baseline to week 48 in both groups， and compared with the TAF group at week 48， the ETV group had a significantly lower eGFR （106.42±14.12 mL/min/1.73 m² vs 112.25±13.44 mL/min/1.73 m²， t=-2.422， P=0.017） and a significantly higher incidence rate of abnormal renal function （17.00% vs 4.00%， χ²=5.092， P=0.024）. After the patients were divided into normal renal function group with 131 patients and abnormal renal function group with 19 patients， the univariate analysis showed that there were significant differences between the two groups in age （Z=-2.039， P=0.041）， treatment drug （ETV/TAF） （χ²=5.092， P=0.024）， and baseline eGFR level （t=4.023， P<0.001）， and the multivariate Logistic regression analysis showed that baseline eGFR （odds ratio ［OR］=0.896， 95% confidence interval ［CI］： 0.841 — 0.955， P<0.001） and treatment drug （OR=5.589， 95%CI： 1.136 — 27.492， P=0.034） were independent influencing factors for abnormal renal function. Baseline eGFR had an area under the ROC curve of 0.781 in predicting abnormal renal function in CHB patients， with a cut-off value of 105.24 mL/min/1.73 m²， a sensitivity of 73.68%， and a specificity of 82.44%. The Kaplan-Meier curve analysis showed that the patients with baseline eGFR≤105.24 mL/min/1.73 m² had a significantly higher cumulative incidence rate of abnormal renal function than those with baseline eGFR>105.24 mL/min/1.73 m² （χ²=22.330， P<0.001）， and the ETV group had a significantly higher cumulative incidence rate of abnormal renal function than the TAF group （χ²=4.961， P=0.026）. With the initiation of antiviral therapy， both the ETV group and the TAF group had a significant reduction in eGFR （F=5.259， P<0.001）， but the ETV group only had a significant lower level of eGFR than the TAF group at week 48 （t=-2.422， P=0.017）； both the baseline eGFR≤105.24 mL/min/1.73 m² group and the baseline eGFR>105.24 mL/min/1.73 m² group had a significant reduction in eGFR （F=5.712， P<0.001）， and there was a significant difference in eGFR between the two groups at baseline and weeks 12， 24， 36， and 48 （t=-13.927， -9.780， -8.835， -9.489， and -8.953， all P<0.001）. ConclusionFor CHB patients initially treated with ETV or TAF， ETV antiviral therapy has a higher risk of renal injury than TAF therapy at week 48.

Objective To explore the relationship between education level and the risk of all-cause mortality in the middle-aged and elderly (≥45 years old) population in China. Methods Using data from five surveys from 2011-2020, years of education, age, gender, marital status, type of household, alcohol consumption status, smoking status, physical activity, limited ability to perform activities of daily living (ADLs), chronic disease status, and body mass index were collected. According to the survival status，the study participants were divided into a survival group (n=8625) and an all-cause mortality group (n=1735). Cox proportional risk regression model was used to analyze the relationship between years of education and the risk of all-cause mortality in middle-aged and elderly people with stratified analysis. Results The survey was conducted on 10360 research subjects, including 4 983 males and 5 377 females, with an age M(Q_R) of 59(8) years old. A total of 88 187 person years (average 8.512 person years) were followed up, and a total of 1735 deaths were reported over 9 years. The all-cause mortality rate was 19.674 ‰, with an education period M(Q_R) of 5(8) years and a survival time M(Q_R) of 9 (0) years. After adjusting for confounding factors, for every 1 year increase in education, the risk of all-cause mortality decreased by 2.60% [HR=0.974, 95% CI (0.960-0.988)]. The stratified analysis results showed that in the population aged 45-59, for every 1 year increase in education, the risk of all-cause mortality decreased by 1.00% [HR=0.990, 95% CI (0.959,1.021)]; In the population aged 60-74 and over 75, for every 1 year increase in education, the risk of all-cause mortality decreased by 2.70% [HR=0.973, 95% CI (0.948, 0.999)] and 3.50% [HR=0.965, 95% CI (0.929, 1.003)], respectively. Conclusion Improving the education level of middle-aged and elderly people (≥ 45 years old) in China can reduce the risk of all-cause mortality, and elderly education should be vigorously promoted.

ObjectiveTo analyze the metabolomic characteristics of platelets in fibrinogen（FIB） overexpression rats of coronary heart disease with blood stasis syndrome（CHD-BSS）， explore potential biomarkers， and investigate the mechanism of FIB overexpression on CHD-BSS. MethodsSD rats were randomly divided into BSS group and BSS+FIB overexpression group（BSS+FIB group）， with 10 rats in each group. Both the BSS+FIB group and the BSS group were fed a high-fat diet combined with oral administration of vitamin D₃ and subcutaneous injection of isoproterenol， but rats in the BSS+FIB group were overexpressed with FIB during the initial modeling stage by transfection with adeno-associated virus（AAV）. The overexpression level of FIB in rat liver and plasma samples was detected by enzyme-linked immunosorbent assay（ELISA） and real-time fluorescence quantitative polymerase chain reaction（Real time PCR）， as well as the expression level of liver FIB A（FGA） mRNA. The characteristics of metabolites in rat platelet samples were analyzed by ultra-high performance liquid chromatography-quadrupole-electrostatic field orbital trap high-resolution mass spectrometry（UPLC-Q-Exactive Orbitrap-MS）， and the differential metabolites between groups were screened by principal component analysis（PCA） and orthogonal partial least squares-discriminant analysis（OPLS-DA）， and the enriched pathways were analyzed. The accuracy of potential biomarkers in the diagnosis of CHD-BSS was evaluated by receiver operating characteristic（ROC） curve. The expression of autophagy related proteins phosphorylated adenosine monophosphate（AMP） activated protein kinase（p-AMPK）/AMPK， phosphorylated mammalian target of rapamycin（p-mTOR）/mTOR， microtubule-associated protein 1 light chain 3（LC3） Ⅱ/Ⅰ and p62 in platelets were detected by Western blot. ResultsCompared with the BSS group， the expression levels of FIB in liver and plasma samples of the BSS+FIB group were significantly increased（P<0.05， P<0.01）， and the expression level of FIB mRNA in the liver was remarkably increased（P<0.01）， indicating successful overexpression of FIB. Platelet metabolomics results showed significant differences in metabolic profiles between the BSS+FIB group and the BSS group， and a total of 25 significantly enriched metabolic pathways and 8 metabolites involved in these metabolic pathways， among which uric acid， guanosine and ribose 1-phosphate levels were up-regulated， while adenosine diphosphate（ADP）， AMP， guanosine diphosphate（GDP）， adenylosuccinate and norepinephrine levels were down-regulated. The diagnostic ability analysis of differential metabolites showed that all 8 differential metabolites had good diagnostic ability， with an area under the curve（AUC）>0.85. Western blot results showed that compared with the BSS group， the expression levels of p-mTOR/mTOR and p62 proteins in platelets of the BSS+FIB group was significantly reduced（P<0.01）， while the expression levels of p-AMPK/AMPK and LC3Ⅱ/Ⅰ proteins were increased， but the difference was not statistically significant. ConclusionOverexpression of FIB can change the metabolic characteristics of CHD-BSS rat model， involving multiple aspects such as vascular endothelial injury， platelet activation and myocardial function damage. Among them， overexpression of FIB may enhance the occurrence of platelet autophagy， thereby inducing platelet activation and promoting thrombus formation.

Objective : To explore the role of lysophosphatidylcholine acyltransferase 3(LPCAT3) in Erastin-induced ferroptosis of acute myeloid leukemia(AML) cells and its related molecular regulatory mechanisms. Methods : Tetrazolium salt(MTS) method was used to detect the sensitivity of different AML cells to the classic ferroptosis inducer Erastin, real time quantitative polymerase chain reaction(qPCR) was used to detect the basal expression level ofLPCAT3mRNA, and the correlation between them was analyzed. Lentivirus-mediatedLPCAT3overexpression AML cell lines(OE group) and negative control lines(NC group) were constructed. After Erastin intervention, MTS, flow cytometry, and micromethods were used to detect cell viability, lipid reactive oxygen species(ROS), and Malondialdehyde(MDA), respectively. qPCR and Western blot were used to detect unfolded protein response(UPR) classic pathway signaling molecules(PERK, ATF4, GRP78, etc.) expression levels. The above ferroptosis-related indicators were detected after combined intervention with the UPR inhibitor 4-phenylbutyric acid(4-PBA), and the regulatory relationship was analyzed. Results : Four different types of AML cells had different sensitivities to ferroptosis, among which K562 cells were relatively insensitive. The IC50of the four types of AML cells to Erastin was negatively correlated with the expression level ofLPCAT3(r=-0.919,P<0.001). After Erastin intervention, the cell viability of K562 cells in the OE group was significantly inhibited by Erastin compared with the NC group(P<0.001), and the levels of lipid ROS and MDA increased(P<0.001). The results of qPCR and Western blot showed that, compared with the NC group, the mRNA and protein expression of UPR classic pathway moleculesPERK,ATF4, andGRP78mRNA and protein increased in the OE group(P<0.01). After inhibiting the UPR pathway by 4-PBA, the viability of K562 cells decreased(P<0.01), and lipid ROS and MDA levels increased(P<0.01) compared with the uninhibited state. Conclusion Overexpression ofLPCAT3can promote ferroptosis in K562 cells, and this process is negatively regulated by the classical UPR pathway PERK/ATF.

Background As a pillar industry in China, the manufacturing sector has a high incidence of non-fatal occupational injuries. The factors influencing non-fatal occupational injuries in this industry are closely related at various levels, including individual, equipment, environment, and management, making the analysis of these influencing factors complex. Objective To identify influencing factors of non-fatal occupational injuries among manufacturing workers, providing a basis for targeted interventions and surveillance. Methods A total of 2243 frontline workers from cable and shipbuilding enterprises were selected as study subjects to investigate the incidence of non-fatal occupational injuries and collect information at four levels: individual, equipment, management, and environment in past 12 months. Data balancing was performed using resampling, and LASSO regression was used to select factors of non-fatal occupational injuries. The influence degree and type of variables were judged based on the magnitude of the estimated coefficients of each variable, where variables with estimated coefficients > 0 are risk factors, and those <0 are protective factors. The area under the receiver operating characteristic (ROC)curve (AUC) was used to test the performance of the model, with an AUC value > 0.7 indicating good model performance. Results Among the 2243 frontline workers, males accounted for 77.7% (1742 out of 2243), with the main age range being 40-49 years old, representing 29.5% (661 out of 2243), 82.7% of the workers (1854 out of 2243) were married, and 55.6% (1248 out of 2243) had a junior middle school education level. The average monthly income for 51.0% (1144 out of 2243) of the workers was between 5000 and 6999 Chinese Yuan. The incidence of non-fatal occupational injuries among the manufacturing workers was 8.4% (189/2243) in the past 12 months. Among the 22 factors associated with the occurrence of non-fatal occupational injuries (P<0.05), 10 were individual-level factors, including gender, smoking, alcohol consumption, colleague relationships, average exercise duration, job burnout, work fatigue, musculoskeletal disorders, cardiovascular diseases, and neurological and sensory organ diseases; 3 were equipment-level factors, including equipment operability, hazardous workpieces, and safety hazards; 5 were environmental-level factors, including low temperatures, special operations, noise, workspace size, and dirty and disorderly environment; and 4 were management-level factors, including daily working hours, weekly working days, overtime, and pre-job technical training. The AUC value of the LASSO regression model was 0.704 and the final model retained a total of 10 variables. Among them, there were 7 risk factors for non-fatal occupational injuries (coefficient > 0), including safety hazards, musculoskeletal disorders, dangerous workpieces, job burnout, dirty and disorderly environment, smoking, and male gender; and 3 protective factors (coefficient < 0), including pre-job technical training, good colleague relationship, and long working days per week. Conclusion Manufacturing enterprises need to focus on the incidence of non-fatal occupational injuries and conduct targeted interventions for non-fatal occupational injuries by controlling potential safety hazards, providing pre-job technical training, reducing dangerous workpieces, rectifying working environment, and reasonably arranging working hours.

[Objective] To explore the feasibility of using whole blood as a source of NK cells for allogeneic CAR NK cell therapy and activated NK cell reinfusion therapy, and initially construct a technical system for the separation and purification of NK cells from whole blood. [Methods] All peripheral blood mononuclear cells (PBMCs) were enriched from 400 mL of whole blood by manual separation and machine separation, respectively. The erythrocyte loss rate, PBMCs number, NK cell purity of the two methods were compared. NK cells were sorted from PBMCs by three separation and enrichment methods as immunomagnetic bead negative selection method, platelet lysate culture expansion and PERCOLL density gradient separation method, and the purity and yield of NK cells, the activity of NK cells and the tumor-killing ability of the three separation and enrichment methods were compared. [Results] The proportion of NK cells in the lymphocyte population was higher in the manual separation method than in the machine separation method[(13.16±5.16)% vs (8.56±3.92)%, P<0.05]; the number PBMCs was lower in the manual separation method than in the machine separation method[(4.09±1.80)×10⁸vs (6.49±2.16)×10⁸, P<0.05], and there was no difference in the red blood cell loss between the two methods (P>0.05). The purity of NK cells isolated and enriched from PBMCs by manual separation method using immunomagnetic was (96.77±2.31)%; the yield was (56.27±10.47)%; the inhibition of tumor proliferation was (38.67±14.05)%; and the tumor killing rate was (19.90±8.05)%. The purity of NK cells isolated and enriched from PBMCs by manual separation method using platelet lysis culture expansion method was the highest at day 7, which was (54.84±15.80)%; the cell expansion multiple could reach 16.92±6.28 at day 7; the in vitro tumor killing rate of NK cells was (15.83±5.5)%; the tumor inhibition rate was (44.33±13.5)%; and there was no difference in the toxicity and activity of NK cells between the two methods (P>0.05). The purity of NK cells isolated and enriched by PERCOLL density gradient separation method was (15.83±5.82)%, and the yield was (14±6.25)%, which was significantly lower than the other two methods. [Conclusion] PBMCs isolated from whole blood by manual separation and NK cells enriched by negative selection with immunomagnetic beads have the potential to provide NK cell materials for CAR-NK cell therapy, and NK cells enriched by platelet lysate-conditioned medium have the potential to provide NK cells for large-scale NK cell activation reinfusion therapy.

Based on the implementation of GMP, comprehensive improvement of quality control measures, and consideration of the 3Rs principle for experimental animals, Several years ago, WHO, the European Pharmacopoeia and the FDA gradually abolished the testing for abnormal toxicity of biological products, and the Chinese Pharmacopoeia 2025 Edition(Volume Ⅲ)also revised the testing for abnormal toxicity of biological products. In order to help users of the Chinese Pharmacopoeia(Volume Ⅲ) better understand and implement this pharmacopoeia, this article provides a detailed review of the changes in regulatory concepts for abnormal toxicity test in various countries and the process of gradually phasing out abnormal toxicity test, as well as the actual situation of China’s pharmaceutical industry. It also interprets the ideas and considerations for revising the Chinese Pharmacopoeia 2025 Edition(Volume Ⅲ) on abnormal toxicity test for biological products.

ObjectiveTo evaluate the clinical efficacy of Fuzheng Huaji Formula （扶正化积方） for chronic hepatitis B to reduce the incidence of liver cirrhosis and hepatocellular carcinoma. MethodsA retrospective cohort study was conducted， collecting medical records of 118 patients with chronic hepatitis B and 234 patients with hepatitis B-related cirrhosis who visited the hospital between January 1， 2014， and December 31， 2018. The use of Fuzheng Huaji Formula was designated as the exposure factor. Patients receiving antiviral treatment for hepatitis B without concurrent Fuzheng Huaji Formula therapy were included in the western medicine group， while those receiving antiviral treatment combined with Fuzheng Huaji Formula for a cumulative treatment lasting longer than 3 months were included in the combined treatment group. The follow-up observation period was five years. Kaplan-Meier survival analysis was used to assess the cumulative incidence of cirrhosis in patients with chronic hepatitis B and the cumulative incidence of hepatocellular carcinoma in patients with hepatitis B-related cirrhosis. Univariate and multivariate Cox regression analyses were employed to examine the factors influencing the occurrence of cirrhosis and hepatocellular carcinoma. ResultsAmong patients with chronic hepatitis B， there were 55 cases in the combined treatment group and 63 cases in the western medicine group； among patients with hepatitis B-related cirrhosis， there were 110 cases in the combined treatment group and 124 cases in the western medicine group. Five-year follow-up outcomes for chronic hepatitis B patients showed that the cumulative incidence of cirrhosis was 5.45% （3/55） in the combined treatment group and 17.46% （11/63） in the western medicine group， with a statistically significant difference between groups （Z = 2.003， P = 0.045）. Five-year follow-up outcomes for hepatitis B-related cirrhosis patients showed that the cumulative incidence of hepatocellular carcinoma was 8.18% （9/110） in the combined treatment group and 22.58% （28/124） in the western medicine group， also showing a statistically significant difference （Z = 3.007， P = 0.003）. Univariate and multivariate Cox regression analyses indicated that treatment with Fuzheng Huaji Formula is an independent protective factor in preventing the progression of chronic hepatitis B to cirrhosis and the progression of hepatitis B-related cirrhosis to hepatocellular carcinoma （P＜0.05）. ConclusionCombining Fuzheng Huaji Formula with antiviral therapy for hepatitis B can effectively intervene in the disease progression of chronic hepatitis B， reducing the incidence of cirrhosis and hepatocellular carcinoma.

BACKGROUND:Metal-organic frameworks exhibited great potential for bone tissue engineering and bone disease treatment because of its unique merits including tunable porosity,a large specific surface area,good biocompatibility,and easy structure modification. OBJECTIVE:To review the advancements,application,strengths,and weaknesses of metal-organic framework materials in bone repair,arthritis,bone infection,and bone tumors,offering guidance and strategies for future research. METHODS:Web of Science,PubMed,and CNKI databases were searched using Chinese and English keywords"metal-organic frameworks,MOFs,orthopedics,bone repair,bone regeneration,orthopaedic applications,bone tissue engineering,bone infection,arthritis,bone tumor,osteosarcoma"for related literature published from 2015 to 2023.Following initial screening based on inclusion and exclusion criteria,72 articles were finally included for review. RESULTS AND CONCLUSION:(1)During bone repair,metal ions of metal-organic frameworks can induce bone formation by activating specific signaling pathways,which include stimulating osteogenic gene expression,inhibiting osteoclasts,encouraging blood vessel formation,and speeding up bone mineralization.Hence,metal-organic frameworks with metals like calcium,strontium,cobalt,copper,and magnesium ions show significant potential in enhancing bone implant performance.(2)Metal-organic framework materials,especially zinc/cobalt-based metal-organic frameworks,exhibit enzyme-like activities and promote cartilage regeneration by scavenging reactive oxygen species.Compared with natural enzymes,it has the advantages of not easy inactivation and better stability.(3)Zinc-based metal-organic framework materials characterized with wide band gaps,efficient separation and migration of photogenerated carriers,and high stability,the enhancement of photocatalytic activity results from enhancing the excited electron-hole widely used for the eradication of bacteria and tumor cells.(4)Bimetallic metal-organic frameworks,the doping of additional metals,showed critical advantages in optimizing structural performance,such as zinc/magnesium-based metal-organic framework 74 offering increased stability for durable antibacterial activity,and the light absorption capacity and photocatalytic efficiency of tantalum/zirconium-based metal-organic framework greatly improved and thus enhancing the radiation therapy.(5)However,metal-organic framework materials still face challenges in clinical applications,such as the uncertainty of drug release,in vivo safety,and potential immune responses from long-term presence.

BACKGROUND:Spleen has the functions of blood storage,hematopoiesis,and immunity.With the increase of age,the structural degeneration and functional decline of spleen lead to the impairment of immune system function,thus accelerating the aging process of the body.The treatment of spleen aging in tree shrews with highly active umbilical cord mesenchymal stem cells has not been reported. OBJECTIVE:To explore the intervention effect and mechanism of highly active umbilical cord mesenchymal stem cells on spleen aging in tree shrews. METHODS:Highly active umbilical cord mesenchymal stem cells were isolated,cultured,and obtained from the umbilical cord tissue of newborn tree shrews by caesarean section.The differentiation abilities of adipogenesis,osteogenesis,and chondrogenesis were detected by three-line differentiation kit.Cell cycle and surface markers were detected by flow cytometry.The second generation of highly active umbilical cord mesenchymal stem cells were transfected with Genechem Green Fluorescent Protein with infection complex values of 100,120,140,160,180,and 200,respectively,to screen the best transfection conditions.After transfection,the fourth generation of highly active umbilical cord mesenchymal stem cells was injected into the tail vein of tree shrews in the elderly treatment group.The young control group and the aged model group were not given special treatment.After 4 months of treatment,the spleen tissue was taken and the structure of the spleen was observed by hematoxylin-eosin staining.β-Galactosidase staining was used to detect the activity of aging-related galactosidase.Immunohistochemical staining was used to detect the expression levels of p21 and p53 proteins.Ki67 and PCNA immunofluorescence staining was used to detect cell proliferation activity.Immunofluorescence staining was used to detect the expression levels of spleen autophagy protein molecules Beclin 1 and APG5L/ATG5.Reactive oxygen species fluorescence staining was used to detect the content of reactive oxygen species in spleen tissue.CD3 immunofluorescence staining was used to detect the change of the proportion of total T lymphocytes.The secretion levels of interleukin 1β and transforming growth factor β1 in spleen were detected by enzyme linked immunosorbent assay.The distribution of highly active umbilical cord mesenchymal stem cells labeled with green fluorescent protein in spleen tissue was observed by DAPI double staining of nucleus. RESULTS AND CONCLUSION:(1)Highly active umbilical cord mesenchymal stem cells grew in a short spindle shape with fish-like growth,with a large proportion of G0/G1 phase,and had the potential to differentiate into adipogenesis,osteogenesis,and chondrogenesis.(2)Multiplicity of infection=140 and transfection for 72 hours were the best conditions for labeling tree shrews highly active umbilical cord mesenchymal stem cells with Genechem Green Fluorescent Protein.(3)Compared with the aged model group,in the aged treatment group,the spleen tissue cells of tree shrews were arranged closely,and the area of white pulp was increased(P<0.01);the boundary between red pulp and white pulp was clear;the proportion of germinal centers did not show statistically significant difference(P>0.05).The activity level of galactosidase related to spleen tissue aging was decreased(P<0.001),and the expression levels of aging protein molecules p21 and p53 were down-regulated(P<0.001).The expression levels of proliferation-related molecules Ki67 and PCNA were up-regulated(P<0.001,P<0.05);expression levels of autophagy-related molecules Beclin 1 and APG5L/ATG5 were up-regulated(P<0.001),and the content of reactive oxygen species decreased(P<0.001),and the proportion of CD3+T cells increased(P<0.05).The secretion level of interleukin 1β in the aging-related secretion phenotype decreased(P<0.001);no significant difference was found in transforming growth factor β1 level(P>0.05).Compared with the young control group,the above indexes were significantly different in the elderly treatment group(P<0.05).(4)Green fluorescent cells labeled with green fluorescent protein were observed in spleen tissue of tree shrews the elderly treatment group by frozen tissue section observation.The results show that intravenous infusion of highly active umbilical cord mesenchymal stem cells can migrate to spleen tissue,inhibit the production of reactive oxygen species,down-regulate the expression of aging-related proteins,induce autophagy,promote cell proliferation,reduce chronic inflammation,and then improve the structure and function of spleen tissue.