Knee osteoarthritis (KOA) is a prevalent degenerative joint disease characterized by synovial inflammation, cartilage loss. Often manifesting as joint pain and limited mobility, it severely affects the quality of life of patients. Traditional treatment methods such as pharmacological injections and surgical interventions primarily aim to alleviate symptoms but have limited effects on cartilage repair. Human umbilical cord mesenchymal stem cells (hUC-MSCs), due to their anti-inflammatory and chondrogenic capabilities, is considered a new hope for the treatment of KOA. This article synthesizes the latest research findings from both domestic and international sources to discuss the theoretical basis for the clinical application of hUC-MSCs in treating KOA, clinical study design, and efficacy evaluation. It also addresses the challenges in the clinical application of hUC-MSCs and explores future directions, in the hope of providing feasible theoretical support for the treatment of KOA with hUC-MSCs.

BACKGROUND:Cervical disc herniation can cause pain in the neck and shoulder area,as well as radiating pain in the upper limbs.The incidence rate is increasing year by year and tends to affect younger individuals.Fully understanding the biomechanical characteristics of the cervical spine in adolescents is of great significance for preventing and delaying the onset of cervical disc herniation in this age group. OBJECTIVE:To reconstruct cervical spine models for both healthy adolescents and adolescent patients with cervical disc herniation utilizing finite element analysis techniques,to analyze the motion range of the C1-T1 cervical vertebrae as well as the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and the cartilage of the small joints. METHODS:A normal adolescent's cervical spine and an adolescent patient with cervical disc herniation were selected in this study.The continuous scan cervical spine CT raw image data were imported into Mimics 21.0 in DICOM format.The C1-T1 vertebrae were reconstructed separately.Subsequently,the established models were imported into the 3-Matic software for disc reconstruction.The perfected models were then imported into Hypermesh software for meshing of the vertebrae,nucleus pulposus,annulus fibrosus,and ligaments,creating valid geometric models.After assigning material properties,the final models were imported into ABAQUS software to observe the joint motion range of the C1-C7 cervical vertebrae segments under different conditions,and to analyze the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and small joint cartilage of each cervical spine segment. RESULTS AND CONCLUSION:(1)In six different conditions,the joint motion range of the C1 vertebra in the cervical spine models of both normal adolescent and adolescent patient with cervical disc herniation was higher than that of the other vertebrae.Additionally,the joint motion range of each cervical spine segment in normal adolescent was greater than that in adolescent patient with cervical disc herniation.(2)In the cervical spine model of normal adolescent,the maximum stress values in the annulus fibrosus and nucleus pulposus were found on the left side during C2-3 flexion conditions(0.43 MPa and 0.17 MPa,respectively).In the cervical spine model of adolescent patient with cervical disc herniation,the maximum stress values were found on the left side during C7-T1 flexion conditions(0.54 MPa and 0.18 MPa,respectively).(3)In the cervical spine model of normal adolescent,the maximum stress value on the endplate was found on the left side of the upper endplate of C3 during flexion conditions(1.46 MPa).In the model of adolescent patient with cervical disc herniation,the maximum stress value on the endplate was found on the left side of the lower endplate of C7 during flexion conditions(1.32 MPa).(4)In the cervical spine model of normal adolescent,the maximum stress value in the small joint cartilage was found in the C2-3 left rotation conditions(0.98 MPa).In adolescent patient with cervical disc herniation,the stress in the small joint cartilage significantly increased under different conditions,especially in C1-2,with the maximum stress found during left flexion(3.50 MPa).(5)It is concluded that compared to normal adolescent,adolescent patient with cervical disc herniation exhibits altered cervical curvature and a decrease in overall joint motion range in the cervical spine.In adolescent with cervical disc herniation,there is a significant increase in stress on the annulus fibrosus,nucleus pulposus,and endplates in the C7-T1 segment.The stress on the left articular cartilage of the C1-2 is notable.Abnormal cervical curvature may be the primary factor causing these stress changes.

Objective To investigate the correlation of the characteristics of symptomatic middle cerebral artery plaques with the risk of stroke recurrence based on high-resolution vessel wall imaging(HR-VWI).Methods Totally 83 patients hospitalized for acute ischemic stroke(AIS)and transient ischemic attack(TIA)at Jingmen People's Hospital and Yichang Central People's Hospital from January 2019 to August 2022 were selected prospectively,who all underwent the treatment with antiplatelet aggregation and intensive lipid lowering by statins.During the follow-up,AIS or TIA recurrences were determined in case of newly found symptoms of neurological impairment in the same supply area of the responsible vessel or new infarct foci confirmed by cranial diffusion weighted imaging(DWI).The patients with AIS or TIA recurrences were enrolled into a recurrence group,and the remained ones were divided into a non-recurrence group.The recurrence group went through HR-VWI scanning within two weeks of recurrence and statin treatment,and the non-recurrence group was examined with HR-VWI half a year after receiving statin treatment.All the patients had their clinical indexes compared before and after statin treatment,the baseline data of the two groups underwent univariate analysis,and Logistic regression analysis was performed for the high-risk factors related to recurrence.SPSS 22.0 software was used for statistical analysis.Results After six months of statin treatment,all the patients were improved in TC,TG,luminal stenosis rate,high T1WI signal,plaque burden,plaque enhancement rate and NIHSS score,with the differences being significant(all P＜0.05).Univariate analysis showed the recurrence group had higher plaque enhancement rates(P=0.012)and higher plaque burden(P=0.047)when compared with the non-recurrence group,with the differences being significant;the two groups were not statistically different in luminal stenosis rate,high T1WI signal,plaque thickness and remodeling index(all P＞0.05).Multivariate logistic regression analysis indicated the plaque enhancement rate was independently correlated with stroke recurrence within 6 months(P=0.027).Conclusion HR-VWI can effectively assess MCA plaque characteristics in recurrent stroke patients,and high plaque enhancement rate faciliates the evaluation of stroke recurrence.[Chinese Medical Equipment Journal,2025,46(2):63-67]

Objective:To analyze the correlation between thymus dose-volume parameters and lymphopenia in patients with early-stage breast cancer (BC) receiving adjuvant radiotherapy (RT).Methods:Medical records of 54 patients with early-stage BC who received postoperative adjuvant RT in the Second Affiliated Hospital of Soochow University from January to December 2019 were retrospectively analyzed. Absolute lymphocyte counts (ALC) were collected at 1 month before (baseline) and weekly during RT. Lymphopenia was graded based according to the common terminology criteria for adverse events version 5.0 and nadir/baseline ALC was calculated. The thymus was delineated according to anatomical boundaries in the original RT planning system. Dosimetric parameters were obtained from the dose volume histograms. Stepwise multiple linear regression analysis was used to explore the factors associated with nadir/baseline ALC. The cutoff values of dosimetric parameters for predicting ≥grade 3 lymphopenia were obtained using the receiver operating characteristic (ROC) curve.Results:The proportion of 54 patients experiencing ≥ grade 3 lymphopenia was 38.9%. The median value of thymus volume, mean dose, V 5 Gy, V 10 Gy were 14.02 cm 3, 4.95 Gy, 36.18%, and 6.61%, respectively. Stepwise multiple linear regression analysis revealed that baseline ALC ( P=0.005), quadrant location ( P=0.005) and mean thymus dose ( P<0.001) were significantly associated with nadir/baseline ALC. ROC curve analysis indicated that the cutoff values of thymus mean dose, V 5 Gy and V 10 Gy for predicting ≥ grade 3 lymphopenia were 6.12 Gy, 35.2%, and 7.4%, respectively. Conclusions:Lymphopenia in early-stage BC patients is significantly correlated with high dosimetric parameters of the thymus during postoperative adjuvant RT. Thymus may be considered as an organ at risk during RT.

Objective:To comprehensively evaluate the medical service capacity of 50 first batch county medical sub-centers in Guizhou Province,it provides the basis and references for further research on the construction of county medical sub-centers in Guizhou province and improvement of the medical service capacity of township health centers(community health service centers)in Guizhou Province.Methods:Through TOPSIS method,RSR method and the fuzzy combination method,the medical service capacity of the primary medical institutions in the county medical sub-center was evaluated.Results:Among the first batch of 50 county-level secondary medical centers,the top three in terms of medical service capabilities were G18,G6,and G36,while the last three were G27,G15,and G22.Conclusion:There were significant differences in the medical and health service capacity among the 50 sub-centers.It is suggested to continue to increase the support for sub-centers,formulate relevant policies according to local conditions and time conditions,and improve the medical service capacity of sub-centers.

This study was aimed at understanding the resistance status of dairy cow-derived Streptococcus strains in China,and providing scientific guidance for the rational use of antimicrobials and the development of new antimicrobials.Meta-analysis was used to explore the resistance of Streptococcus strains to 20 antimicrobials between 2000 and 2023.A total of 67 articles de-scribing 3 154 strains were included after a literature search,and a meta-analysis was conducted on the overall collection area according to time subgroups for 20 antimicrobials.Streptococci of dairy origin in China showed varying resistance rates(≥30％),as follows:penicillin(60％,95％CI=0.48-0.72),streptomycin(57％,95％CI=0.46-0.68),cotrimoxazole(56％,95％CI=0.28-0.82),lincomycin(51％,95％CI=0.26-0.76),tetracycline(49％,95％CI=0.40-0.59),doxycyc-line(42％,95％CI=0.24-0.60),clindamycin(41％,95％CI=0.28-0.54),ampicillin(39％,95％CI=0.27-0.52),e-rythromycin(37％,95％CI=0.28-0.45),kanamycin(36％,95％CI=0.20-0.54),and amoxicillin(30％,95％CI=0.10-0.53).On the basis of findings in the collection area,the resistance rates of dairy cow-derived Streptococcus to antimicrobials in Northeast China and Southwest China was generally high.The resistance rates of Streptococcus from dairy cattle to antimi-crobial drugs such as tetracycline,doxycycline,and lincomycin increased significantly over time.However,the resistance rates to antimicrobial drugs such as streptomycin,gentamicin,and enrofloxacin showed a significant decreasing trend.Dairy cow-de-rived Streptococcus had high resistance to some antimicrobials,and the resistance varied by region,because of differences in breeding and management.Monitoring of antimicrobial resistance rates,enhancing research on resistance mechanisms,and reg-ulating the use of antimicrobials remain necessary.

This study aims to investigate the epidemic variation of porcine circovirus type2(PCV2)and its distribution in swine farms in Henan Province from 2022 to 2023.In this study,1 206 pig blood samples from 18 urban scale swine farms,and 318 pigs and environmental samples from 2 PCV2-positive swine farms in Henan Province were detected by fluorescence quantitative PCR.ORF2 gene sequencing and genetic evolution analysis were performed on the positive samples.The results showed that the positive rate of PCV2 was 7.05％(85/1 206)in Henan Province,11.15％in western Henan Province and 3.03％in southern Henan Province.The positive rate of PCV2 in spring was 11.60％(67/576).A total of 31 ORF2 gene sequences were obtained,of which 23 were PCV2d(74.19％),6 were PCV2a(19.35％),one was PCV2b(3.23％)and one was PCV2c(3.23％).The results of amino acid sequence comparison showed that the mutation sites mainly concentrated on amino acids at positions 40-68 and 180-209.The total positive rate of pig farm sam-ples was 37.42％(119/318),and the positive rate of pig samples from different types of pig houses was 60.71％(34/56),45.83％(11/24),35.09％(20/57),and 33.33(3/9)in order from high to low.The positive rate of environmental samples from high to low was 56.36％(31/55)in feeding system,46.67％(7/15)in feces system,12.50(1/8)in decontamination area,11.11％(2/18)in living area,and no PCV2 was detected in ventilation system.The highest positive rate was 45.00％(9/20)for the tools in the house,7.14％(1/14)for the surface and sole of the clothes after leaving the house,and no PCV2 was detected on the surface and sole of the clothes before entering the house.In this study,the epidemiological investigation of PCV2 in Henan Province and its distribu-tion in swine farms were carried out,and the main circulating strains,seasons,regions and gene mutations of PCV2 in H enan Province were identified.The distribution and transmission routes of PCV2 in positive pig farms were preliminarily analyzed and summarized,which provided data basis and reference for effective prevention and control of PCV and the establishment of accurate bio-safety prevention and control measures.

Objective:Exploring the effect of Pinocembrin(Pino)regulating the Ras homolog gene family member A/Rho associated with curly helix binding protein kinase(RhoA/ROCK)signaling pathway of Ras homologous gene family members on the malignant biological behavior of gastric cancer cells.Methods:Cultivate human gastric cancer cells MGC803 with different concentrations of Pino(0～240μmol/L),detect cell survival rate using CCK-8 method,and screen for the optimal drug concentration.MGC803 cells were rseparated into MGC803 group(Control group),Pino-L group,Pino-M group,Pino-H group,and Pino-H+RhoA agonist CN03 group.The clone formation experiment was applied to detect the number of clones formed of cells in each group.Assessment of cell apoptosis using flow cytometry.Tran-swell invasion and migration experiments were used to detect the number of cells undergoing migration and invasion in each group;Detection of RhoA/ROCK signaling pathway and expression of epithelial mesenchymal transition related proteins in MGC803 cells using Western blot method.Results:Compared with the MGC803 group,the cell survival rate,clone formation number,migration cell number,and invasion cell number were all reduced in the Pino-L group,Pino-M group,and Pino-H group,and RhoA was also present in the cells,ROCK2,The expression levels of vimentin and N-cadherin gradually decreased(P<0.05),while the apoptosis rate and E-cadherin expression level gradually in-creased(P<0.05).The Pino-H+CN03 group reversed the trend of changes in the above indicators).Conclusion:Pino can prevent malignant biological behavior of gastric cancer cells,which may be related to the inhibition of the RhoA/ROCK signaling pathway.

In recent years,the market share of food and medicine homology substances has continued to grow,and various types of contamination issues have become the focus of attention both inside and outside the industry.The contamination not only affects the original medicinal quality,but also leads to the accumulation of toxic substances in the human body,causing acute and chronic severe hazards such as vomiting,poisoning and cancer.Therefore,the development of biosensors that can conveniently,accurately and sensitively detect various pollutants in food and medicine homology substances has become a research hotspot.Aptasensors based on metal-organic frameworks(MOFs)with advantages such as strong specificity,rapid response and simple operation,have been widely used in detection of various pollutants.This review focused on the research progress of aptasensors based on MOFs for detection of food and medicine homology contamination in the past few years,and provided a detailed comparison and analysis for detection of chemical pollutants(such as pesticide residues,heavy metal residues,mycotoxins,etc.)and microbial contamination in food and medicine homology substances.Besides,the development trend and possible challenges of MOFs aptasensors in detection of food and medicine homology substances in the future were discussed,which was anticipated to provide a reference for the development of new MOFs aptasensors.

Enzymatic cascade catalysis has emerged as an effective means to enhance the sensitivity of biosensors due to its remarkable amplification effect on electrochemical signals.However,the most used natural enzymes have high specificity and high catalytic activity,but are susceptible to environmental factors,easy denaturation and inactivation,and high cost,which limit their practical applications.Additionally,the majority of nanozymes with excellent catalytic activity cannot be directly used as redox probes.The redox signal can only be required under high potentials in strong acid/alkali solutions,or functionalized with electroactive substances.To tackle this problem,herein,AuNPs(glucose oxidase-like activity)and Mn,Zr dual-doped CeO2 nanozymes(Mn,Zr-CeO2,peroxidase-like activity)were used as model enzymes to construct a high-performance nanozymes cascade catalytic system.Owing to high Ce4+/Ce3+ratio and a considerable number of oxygen vacancies,Mn,Zr-CeO2 nanozymes exhibited excellent peroxidase-like activity and could generate amplified electrochemical signals in neutral medium at low potentials.Furthermore,the porous structure of Mn,Zr-CeO2 nanozymes could accelerate the mass transfer of intermediate H2O2,thereby enhancing the efficiency of enzymatic cascade catalysis.As a result,a label-free electrochemical biosensor was constructed for sensitive detection of the cancer marker miRNA-21 at physiological pH,with a detection limit as low as 32.5 fmol/L.This strategy offered a novel approach for the development of a new generation of high-performance nanozymes cascade platforms,which could be widely applied in the fields such as biotechnology,bioanalysis,and disease diagnosis.