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published before September 2024 in CNKI,PubMed,and Web of Science databases.Articles with poor relevance to the topic,outdated,or duplicated content were excluded,and finally,109 articles were included for review.RESULTS AND CONCLUSION:(1)This paper reviews recent methods for isolating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:Periprosthetic joint infection is the most common cause of early failure after total knee replacement.The current methods of preventing periprosthetic joint infection by improving the surface of the prosthesis have limitations to varying degrees.OBJECTIVE:To construct a coating material that can stably improve the surface of the implant,prevent the initial floating bacterial infection of periprosthetic infection,and regulate the bone transfer function around the implant.METHODS:(1)Material preparation:YGF polypeptide(which promotes bone formation),LL-37 polypeptide(with antibacterial properties)and YGF+LL-37 composite peptide were prepared by Fmoc solid phase peptide synthesis technology.The titanium-based materials were immersed in the three polypeptide solutions for 2 hours to obtain YGF coating,LL-37 coating and composite peptide coating coated titanium sheets.(2)In vitro experiment:Uncoated titanium sheets and coated titanium sheets were co-cultured with Escherichia coli(or Staphylococcus aureus)and the colonies were counted by plate method.MC3T3 cells were inoculated on the surface of uncoated titanium sheet and coated titanium sheet,respectively.Alizarin red staining was used to observe the calcium salt deposition on the surface of the material.Western blot assay was used to detect the protein expression of RUNX2,osteocalcin,osteopontin,and bone morphogenetic protein 2.(3)Animal experiment:24 SD rats were randomly divided into three groups:the blank group(n=8)was implanted with uncoated titanium nails in the femoral medullary canal;the control group(n=8)was implanted with uncoated titanium nails in the femoral medullary canal+intra-articular injection of Staphylococcus aureus suspension;the experimental group(n=8)was implanted with composite peptide coated titanium nails in the femoral medullary canal+intra-articular injection of Staphylococcus aureus suspension.After 5 weeks of implantation,micro-CT examination,hematoxylin-eosin staining and immunohistochemical staining of femur specimens were performed.RESULTS AND CONCLUSION:(1)In vitro experiment:Compared with uncoated titanium sheet and YGF coated titanium sheet,LL-37 coated and composite peptide coated titanium sheet could significantly inhibit the growth and reproduction of Escherichia coli and Staphylococcus aureus.Compared with uncoated titanium sheets and LL-37-coated titanium sheets,YGF-coated and composite peptide-coated titanium sheets could promote calcium salt deposition in osteoblasts and increase the protein expression of RUNX2,osteocalcin,osteopontin and bone morphogenetic protein 2.(2)Animal experiment:Micro-CT test showed that the control group had less bone mass than the blank group and the experimental group.Hematoxylin-eosin staining showed that there was a large amount of fibrous tissue around the nail channel in the control group,only a small amount of tissue fibrosis around the nail channel in the blank group,and only a small amount of tissue fibrosis around the nail channel in the experimental group.Immunohistochemical staining showed that the protein expression of interleukin 1β and tumor necrosis factor α in the control group was higher than that in the blank group and the experimental group,and the expression of osteocalcin,RUNX2 and osteopontin in the experimental group was higher than that in the blank group and the control group.(3)The results show that the titanium-based material coated with YGF+LL-37 composite peptide coating has good antibacterial ability and can promote bone transfer around the implant.

BACKGROUND:Currently,treatment method for knee osteoarthritis includes oral medicine,joint cavity drug injection,and physiotherapy,but the curative effect is limited.Existing studies have confirmed that silicon-based bioceramics can promote cartilage and subchondral bone repair and vascular regeneration.OBJECTIVE:To explore the effect of different concentrations of silicon-based bioceramics injected into the knee joint cavity in the treatment of knee osteoarthritis in rats.METHODS:Silicon-based bioceramics-calcium silicate was prepared.Twenty-five SD rats were randomly divided into five groups,with five rats in each group.The healthy group did not receive any intervention,and the modeling group,low-dose calcium silicate group,high-dose calcium silicate group,and saline group used anterior cruciate ligament transection to establish bilateral knee osteoarthritis models.Four weeks after modeling,0.05 mL of 50 and 100 mg/mL calcium silicate solution were injected into the knee joint cavity in the low-dose calcium silicate group and high-dose calcium silicate group,respectively,and 0.05 mL of saline was injected into the knee joint cavity in the saline group,once a week for 4 consecutive weeks.In the fifth week of administration,bilateral knee joint Micro-CT detection,knee joint cartilage hematoxylin-eosin staining,and modified Mankin score were performed.RESULTS AND CONCLUSION:(1)Micro-CT quantitative analysis showed that compared with the healthy group,the volume fraction and number of trabeculae of the medial tibial plateau in the modeling group decreased(P＜0.05),and the separation of trabeculae increased(P＜0.05).Compared with the modeling group,the volume fraction and number of trabeculae of the medial tibial plateau in the low-dose calcium silicate group and the saline group increased(P＜0.05),and the separation of trabeculae decreased(P＜0.05).(2)Hematoxylin-eosin staining showed that the cartilage surface of the healthy group and the low-dose calcium silicate group was relatively smooth and flat,the chondrocytes were evenly distributed,without clustered chondrocytes,the tide line was complete,and the staining was uniform;the cartilage surface of the high-dose calcium silicate group was slightly uneven,the middle and deep cells were disordered,with a small number of clustered chondrocytes,the tide line was discontinuous,and the staining was uneven;the cartilage surface of the saline group and the modeling group was obviously rough,the cells were disordered,with a large number of clustered chondrocytes,the tide line disappeared,and the staining was uneven.The modified Mankin score of the healthy group was lower than that of the high-dose calcium silicate group,the saline group,and the modeling group(P＜0.05).The modified Mankin score of the high-dose calcium silicate group and the low-dose calcium silicate group was lower than that of the saline group and the modeling group(P＜0.05).(3)The results show that calcium silicate knee joint injection has a certain effect in the treatment of knee osteoarthritis.Compared with 100 mg/mL calcium silicate solution,50 mg/mL calcium silicate solution can promote the recovery of subchondral bone and cartilage.

BACKGROUND:Arthroscopic anchor repair has become the main treatment method for rotator cuff tears at present.Among them,the insertion status of the anchor is a key factor in the success or failure of the operation.However,currently,the impact of the insertion depth of the anchor on the stress of the bone tunnel and the anchor under different bone density conditions remains unclear.OBJECTIVE:To explore the stress distribution of the bone tunnel and the anchor when the insertion depth of the anchor varies under different bone density conditions by using three-dimensional finite element analysis technology.METHODS:The CT image data of the humerus of volunteers were collected,and the models of the humerus and the anchor were constructed by using Mimics,3-Matic,and Solidworks software.In 3-Matic,holes with distances of 0,2,4,6,and 8 mm from the surface of the humerus were respectively created at the same position of the humerus and assembled with the anchor.In Mimics,values were assigned based on the CT gray value to obtain a model with normal bone mass(T value ≥-1.0).The parameters were changed to construct models with reduced bone mass(-2.5＜T value＜-1.0)and osteoporosis(T value＜-2.5).In each model,a 70 N pulling force was applied to the anchor along the direction tangent to the inner edge of the bone tunnel.The stress distribution and magnitude of the bone tunnel and the anchor when inserted at different depths under different bone density conditions were observed.RESULTS AND CONCLUSION:(1)When the insertion depth was the same,as the bone density decreased,the maximum equivalent stress of the anchor increased,while the maximum equivalent stress of the bone tunnel decreased.(2)When the bone density was the same,as the insertion depth of the anchor increased,the maximum equivalent stress of the anchor decreased.When the insertion depth was 4 mm,the stress of the bone tunnel was the smallest and the distribution was relatively uniform.The stress of the anchor was mainly distributed around the lower anchor hole and the proximal thread,and the stress of the bone tunnel was mainly at the part in contact with the proximal thread.The increase in the insertion depth would change the uniformity and pattern of the stress distribution,while the bone density had a relatively small impact on the stress distribution pattern.(3)It is concluded that the bone density of the humerus is crucial for the anchor repair of rotator cuff tears.It is recommended that clinicians measure the bone density of the greater tuberosity of the humerus before the operation.Excessive insertion depth of the anchor does not significantly increase its stability.Clinicians can conduct personalized preoperative assessments by using the finite element analysis method in combination with the actual situation of patients to achieve the best surgical results.

OBJECTIVE:Postoperative recurrence is a common complication of percutaneous endoscopic lumbar discectomy for lumbar disc herniation,which can significantly increase the risk of reoperation.A well-performing risk prediction model can help identify high-risk groups early and prevent postoperative recurrence.This study systematically evaluated the risk prediction model for postoperative recurrence after percutaneous endoscopic lumbar discectomy to provide a reference for surgical decision-making.METHODS:The PubMed,Embase,Web of Science,CNKI,WanFang Data,VIP,and CBM were electronically searched to collect studies on the recurrence risk prediction models after percutaneous endoscopic lumbar discectomy from inception to July 1,2024.Two reviewers independently screened the literature and extracted data.The models' risk of bias,applicability,and report quality were assessed using prediction model risk of bias assessment tool(PROBAST)and Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis(TRIPOD)tools,respectively.Meta-analysis of postoperative recurrence rate of percutaneous endoscopic lumbar discectomy and related predictors was performed using Revman 5.4 software.RESULTS:(1)A total of 15 studies were included,all of which were retrospective studies,including 24 models for predicting the risk of recurrence after percutaneous endoscopic lumbar discectomy.(2)The PROBAST evaluation results indicated that all 15 studies exhibited a high risk of bias.Regarding applicability,two studies demonstrated a low risk,while 13 presented a high risk.(3)Regarding the TRIPOD reporting quality,the overall quality across the 15 studies was low.The primary reasons for this low compliance included the failure to report blinding,a lack of explanation for the sample size calculation method,lack of detailed description of missing data processing methods,and lack of information such as introduction to the model used.(4)Furthermore,the area under the receiver operating characteristic curve for the model ranged from 0.684 to 0.972,with the number of potential predictor variables varying from 15 to 28.(5)The results of meta-analysis showed that the postoperative recurrence rate of lumbar disc herniation patients treated with percutaneous endoscopic lumbar discectomy was 12％(95％CI=9.0％-15.0％),Modic changes(OR=6.72,95％CI=3.90-11.59),body mass index(OR=1.28,95％CI=1.10-1.49),work intensity(OR=3.22,95％CI=1.85-5.59),age(OR=2.28,95％CI=1.50-3.48),and smoking history(OR=2.65,95％CI=1.75-4.00)were independent influencing factors for postoperative recurrence of percutaneous endoscopic lumbar discectomy(all P＜0.05).CONCLUSION:The overall predictive performance of the recurrence risk prediction models after percutaneous endoscopic lumbar discectomy is satisfactory;however,the model exhibits a high overall risk of bias and applicability,coupled with low reporting quality.Additionally,there is a lack of prospective research and external validation.Future,risk prediction models should consider factors such as Modic changes,body mass index,work intensity,age,and smoking history as potential predictors.

ObjectiveTo explore the mechanism of Shenmai injection in improving cisplatin resistance in non-small cell lung cancer （NSCLC） based on the endoplasmic reticulum stress through protein kinase R-like endoplasmic reticulum kinase （PERK）/activated transcription factor 4 （ATF4）/C/EBP homologous protein （CHOP） signaling pathway. MethodsBALB/c nude mice bearing cisplatin-resistant human lung cancer cell line （A549/cisplatin） were randomly divided into four groups： Blank control group （0.9% sodium chloride）， cisplatin group （5 µg·g^-1cisplatin）， Shenmai injection group （5.2 mg·g^-1 Shenmai injection）， and combination therapy group （5.2 mg·g^-1 Shenmai injection +5 µg·g^-1cisplatin）. The drug intervention lasted for 4 weeks， and the changes in body weight and tumor volume were monitored. Hematoxylin-eosin （HE） staining was performed to observe tumor tissue pathology. Transmission electron microscopy （TEM） was used to assess the morphology of the endoplasmic reticulum. Immunohistochemical assay was conducted to measure the positive expressions of PERK， ATF4， and CHOP in tumor tissues. Western blot quantified the protein expression of immunoglobulin heavy chain binding protein （BIP）， PERK， phosphorylated PERK （p-PERK）， eukaryotic translation initiation factor 2α （eIF2α）， phosphorylated eIF2α （p-eIF2α）， ATF4， CHOP， B-cell lymphoma -2 （Bcl-2）， and Bcl-2 Associated X protein （Bax）. A549/cis cells were divided into blank group： Blank control group （normal culture medium）， cisplatin group （23.3 µmol·L^-1 cisplatin）， Shenmai Injection group （20 g·L^-1 Shenmai injection）， and combination therapy group （20 g·L^-1 Shenmai injection+23.3 µmol·L^-1 cisplatin）. Cell counting kit-8 （CCK-8） method was used to detect cell viability， TEM was used to observe the morphology of endoplasmic reticulum， and Western blot was used to detect endoplasmic reticulum stress and apoptosis-related proteins. ResultsCompared with the cisplatin group， the combination therapy group showed increased body weight （P<0.05）， decreased tumor volume （P<0.05）， and expanded endoplasmic reticulum in tumor cells. The positive expressions of PERK， ATF4， and CHOP increased （P<0.05）. Western blot revealed elevated protein expression levels of BIP， p-PERK/PERK， p-eIF2α/eIF2α， ATF4， CHOP， and Bax （P<0.05）， while Bcl-2 expression decreased （P<0.05）. As shown in the in vitro experiment， compared with the cisplatin group， the combination therapy group exhibited a reduced cell survival rate （P<0.05）. TEM revealed increased endoplasmic reticulum dilation and vesicular degeneration. Western blotting showed increased protein levels of BIP， p-PERK/PERK， p-eIF2α/eIF2α， ATF4， CHOP and Bax （P<0.05）， with decreased Bcl-2 expression （P<0.05）. ConclusionShenmai injection combined with cisplatin has a synergistic antitumor effect in NSCLC， which may be attributed to the activation of endoplasmic reticulum stress response mediated by the PERK/eIF2α/ATF4/CHOP signaling pathway and the induction of tumor cell apoptosis.

Neurocritical care involves complex pathophysiological mechanisms, and its incidence is higher, injuries are more severe, and treatment is more challenging in high-altitude environments. This consensus, based on the latest domestic and international evidence-based medical data, establishes a standardized, goal-oriented framework for neurocritical care management applicable in high-altitude regions and nationwide. The consensus was developed following international standards for evidence quality assessment and underwent two rounds of Delphi expert consultation, resulting in 32 recommendation statements covering three parts: management systems, monitoring and assessment, and core strategies. Key updates include: advocating for the establishment of independent neurocritical care units and implementing precise tiered diagnosis and treatment based on the "Five Differences in Critical Care" concept; constructing a "trinity" multimodal brain monitoring system centered on cerebral blood flow, cerebral oxygenation, and brain function, emphasizing routine bedside transcranial Doppler ultrasound, cerebral oximetry, and continuous electroencephalography monitoring; shifting management strategies from mild hypothermia therapy to targeted temperature management, and defining the "446" target management pathway for the supercritical stage; emphasizing the assessment of static and dynamic cerebrovascular autoregulation functions through multimodal methods to achieve individualized optimal mean arterial pressure management; elevating cerebrospinal fluid management goals to the level of "glymphatic system" function maintenance; implementing a multidisciplinary collaborative, whole-process management model focusing on patients' long-term neurological functional outcomes; de-escalation criteria include multidimensional indicators such as recovery of brain structure, restoration of cerebrovascular autoregulation, improvement in cerebrospinal fluid dynamics, and reduction in biomarker levels; and integrating cutting-edge technologies like artificial intelligence into post-critical care management and rehabilitation planning. This consensus systematically integrates the entire process of neurocritical care management, reflecting the modern connotation of goal-oriented, dynamic, and multimodal integration in neurocritical care medicine. It aims to adapt to new trends such as deepening understanding of pathophysiological mechanisms, the integration of medicine and engineering, and the empowerment of artificial intelligence, thereby further advancing the discipline of critical care medicine.

Objective: To investigate the distribution characteristics of ABO and Rh blood group antigen phenotypes among blood donors in the Yantai, Shandong. Methods: Blood samples from 310 180 voluntary blood donors in Yantai collected from January 2019 to December 2023 were tested for ABO and Rh blood group antigens using standard serological methods. RhD-negative samples were further typed for C, c, E, and e antigens. Population genetic analysis of blood groups was performed: allele frequencies were inferred from ABO phenotypes, and Rh allele/haplotype frequencies were estimated based on the proportion of RhD-negative donors and CcEe antigen typing, followed by Hardy-Weinberg equilibrium testing. Results: The phenotypic distribution frequency of ABO blood groups was B(32.72%)>O(28.93%)>A(27.65%)>AB(10.70%). The inferred allele frequencies were r(53.74%)>q(24.78%)>p(21.48%), consistent with Hardy-Weinberg equilibrium (P>0.05). A total of 1 872 Rh-negative donors (0.603%) were identified. The most common Rh phenotypes were ccdee (59.56%) and Ccdee (30.18%). The distribution of Rh antigen phenotypes deviated significantly from Hardy-Weinberg equilibrium (χ =37.15, P<0.001), with the cde haplotype showing the highest frequency. There was no statistically significant difference in ABO blood group distribution between RhD-positive and RhD-negative donors (P>0.05). Conclusion: The ABO blood group distribution among voluntary blood donors in Yantai is generally stable and consistent with population genetic equilibrium, whereas the Rh antigen phenotype distribution deviates from equilibrium, indicating potential underlying genetic structural differences.

ObjectiveTo observe the mechanism of Guihuang formula in regulating the activation of NOD-like receptor protein 3 （NLRP3） inflammasome and inhibiting pyroptosis in the treatment of type Ⅲ prostatitis. Methods（1） In an animal experiment， 50 Sprague Dawley （SD） rats were randomly divided into a blank group， a model group， and low-dose， medium-dose， and high-dose groups of Guihuang formula， with 10 rats in each group. Except for the blank group， the type Ⅲ prostatitis rat model was prepared for the other four groups.After the modeling was successful， the blank group and the model group were given normal saline intragastrically， and the low-dose， medium-dose， and high-dose groups of Guihuang formula were given intragastrically with Guihuang formula （4.9， 9.8， 19.6 g·kg^-1）. After 30 days of intragastrical administration， samples were taken for detection. Inflammatory cell infiltration in prostate tissue was observed by hematoxylin-eosin （HE） staining， and serum IL-1β and IL-18 levels were measured by enzyme-linked immunosorbent assay （ELISA）. Serum malondialdehyde （MDA）， superoxide dismutase （SOD）， and glutathione peroxidase （GSH-Px） levels were determined by biochemistry. NLRP3 expression in prostate tissue was assessed by immunohistochemistry， and the expression of NLRP3， cysteine-aspartic acid protease-1 （Caspase-1）， and gasdermin D （GSDMD） in prostate tissue was measured by Western blot. （2） In a cell experiment， human normal prostate epithelial cells （RWPE-1 cells） were divided into a blank group， a model group， a Guihuang formula group， and an NLRP3 inhibitor group （MCC950 group）. Except for the blank group， the other three groups were stimulated by 100 μg·L^-1 lipopolysaccharide （LPS） for 4 h and 5 mol·L^-1 adenosine triphosphate （ATP） for 30 min to prepare the pyroptosis model. After successful modeling， blank serum was given to the blank group and the model group. 6.25 μg·mL^-1 Guihuang formula drug-containing serum was added to the Guihuang formula group， and MCC950 was added to the MCC950 group on the basis of the model group. Propidium iodide （PI） uptake and Caspase-1 expression were detected by flow cytometry， and lactate dehydrogenase （LDH） level in the cell supernatant was measured by biochemistry. Interleukin （IL）-1β and IL-18 levels of the cell supernatant were determined by ELISA， and the expression of NLRP3， Caspase-1， and GSDMD was detected in Western blot. Results（1） For the animal experiment， compared with the blank group， the model group showed significant infiltration of inflammatory cells in prostate tissue， while the low-dose， medium-dose， and high-dose groups of Guihuang formula showed reduced infiltration of acinar inflammatory cells， reduced degree of glandular epithelial degeneration and interstitial edema， and significantly reduced degree of damage. Compared with those in the blank group， the levels of IL-1β and IL-18 in the serum of the model group were significantly increased （P<0.01）. Compared with the model group， the low-dose， medium-dose， and high-dose groups of Guihuang formula showed a significant decrease in serum IL-1β and IL-18 levels （P<0.01）. Compared with that in the blank group， the serum MDA level in the model group significantly increased （P<0.01）. Compared with that in the model group， the MDA level in the low-dose， medium-dose， and high-dose groups of Guihuang formula was significantly reduced （P<0.01）. Compared with those in the blank group， the levels of SOD and GSH-Px in the serum of the model group significantly decreased （P<0.05）. Compared with the model group， the low-dose， medium-dose， and high-dose groups of Guihuang formula showed a significantly increase in SOD （P<0.01）. Compared with the model group， the low-dose， medium-dose， and high-dose groups of Guihuang formula showed a significantly increase in GSH-Px （P<0.05）. Immunohistochemistry showed that compared with the blank group， the model group had high expression of NLRP3 molecule in prostate tissue. The expression of NLRP3 in the low-dose， medium-dose， and high-dose groups of Guihuang formula was significantly lower than that in the model group. Compared with those in the blank group， the expression levels of NLRP3， Caspase-1， and GSDMD proteins in the prostate tissue of the model group were significantly increased （P<0.01）. Compared with those in the model group， the expression levels of NLRP3， Caspase-1， and GSDMD proteins in the low-dose， medium-dose， and high-dose groups of Guihuang formula were significantly inhibited （P<0.01）. （2） For the cell experiment， compared with that in the blank group， the PI uptake rate of RWPE-1 cells in the model group significantly increased （P<0.01）. Compared with that in the model group， the PI uptake rate of the Guihuang formula group and the inhibitor group significantly decreased （P<0.01）. Compared with that in the blank group， the expression of Caspase-1 in the model group was significantly higher （P<0.01）. Compared with that in the model group， the Caspase-1 in the Guihuang formula group and the inhibitor group significantly decreased （P<0.01）. Compared with the blank group， the model group showed an increase in LDH release （P<0.01）. Compared with the model group， the Guihuang formula group and the inhibitor group showed a significantly decrease in LDH release （P<0.01）. Compared with those in the blank group， the levels of IL-1β and IL-18 in the supernatant of the model group were significantly increased （P<0.01）. Compared with the model group， the Guihuang formula group and the inhibitor group showed a significantly decrease in the levels of IL-1β and IL-18 （P<0.01）. Compared with those in the blank group， the expression levels of NLRP3， Caspase-1， and GSDMD proteins significantly increased in the model group （P<0.01）. Compared with those in the model group， the protein expression levels of NLRP3， Caspase-1， and GSDMD were significantly reduced in the Guihuang formula group and inhibitor group （P<0.01）. ConclusionGuihuang formula can inhibit the activation of Caspase-1， prevent GSDMD cleavation and lysis， and inhibit cell pyrodeath in the treatment of type Ⅲ prostatitis by inhibiting the activation of NLRP3 inflammasome.

ObjectiveTo identify the pathogen species responsible for the wilt disease of Tetradium ruticarpum in Chongqing， investigate there biological characteristics， and screen effective fungicides， so as to provide a theoretical basis for disease control in production. MethodsThe pathogen was isolated via the tissue culture method. Pathogenicity was verified according to Koch's postulates. The pathogen was identified based on morphological characteristics and multi-gene phylogenetic analysis. The mycelial growth rate method was used for biological characterization of the pathogen and fungicide screening. ResultsThe pathogen colonies were nearly circular with irregular edges， white， short， velvety aerial hyphae， and pale purple undersides. Macroconidia were colorless， sickle-shaped， with 3-5 septa， while microconidia were transparent， elliptical， aseptate or with 1-2 septa. Multi-gene phylogenetic analysis showed that the pathogen clustered in the same clade as Fusarium fujikuroi with 100% support， which， combined with morphological characteristics， identified the pathogen causing wilt of T. ruticarpum in Chongqing as F. fujikuroi. The optimal conditions for the mycelial growth of F. fujikuroi were mung bean agar （MBA） with glucose as the carbon source， beef extract and yeast powder as nitrogen sources， 28 ℃， pH 7.0， and alternating light/dark conditions. The optimal conditions for sporulation were potato dextrose agar （PDA） with glucose as the carbon source， beef extract as the nitrogen source， 28 ℃， pH 7.0， and complete darkness. Among chemical fungicides， phenazine-1-carboxylic acid exhibited the strongest inhibitory effect on F. fujikuroi. Shenqinmycin and tetramycin were the most effective bio-fungicides. ConclusionThis study is the first to report F. fujikuroi as the causal agent of wilt disease in T. rutaecarpa. The chemical fungicide phenazine-1-carboxylic acid and the bio-fungicides shenqinmycin and tetramycin showed strong inhibitory effects against F. fujikuroi.