BACKGROUND:The mesenchymal stem cell secretome contains bioactive substances,cytokines,and growth factors.Three-dimensional cell culture can regulate the secretion of these components,potentially enhancing the ability to promote injury repair.OBJECTIVE:To investigate the repair effect of three-dimensional cultured human umbilical cord mesenchymal stem cell secretome on skin injuries in mice.METHODS:Human umbilical cord mesenchymal stem cells were cultured in conventional two-dimensional culture dishes and 96-well U-bottom cell culture plates,from which their secretory components were subsequently collected.The expression of skin damage repair related secretory factors in umbilical cord mesenchymal stem cells was analyzed using RT-qPCR.The protein expression level of skin damage repair related factors in umbilical cord mesenchymal stem cell secretome was detected using enzyme-linked immunosorbent assay.The potential of human umbilical cord mesenchymal stem cell secretome to repair vascular injuries was evaluated using an immortalized human umbilical vein endothelial cell migration model.A mouse skin injury model was established,and the human umbilical cord mesenchymal stem cell secretome was injected subcutaneously.Repair effects on skin injury were assessed through wound healing rates and histopathological analysis.RESULTS AND CONCLUSION:(1)After three days of cultivation,human umbilical cord mesenchymal stem cells cultured in two dimensions exhibited a fibroblast-like,swirling growth pattern,whereas three-dimensional culture led to the formation of uniform microspheres.(2)Compared with two-dimensional culture,three-dimensional culture significantly increased the mRNA expression of transforming growth factor β and basic fibroblast growth factor in human umbilical cord mesenchymal stem cells.(3)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly enhanced the protein expression of vascular endothelial growth factor,interleukin-10,and granulocyte-macrophage colony-stimulating factor in the human umbilical cord mesenchymal stem cell secretome.(4)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly promoted the migration of immortalized human umbilical cord mesenchymal stem cells.(5)Compared with the untreated control group and the two-dimensional cultured human umbilical cord mesenchymal stem cell secretome,the three-dimensional cultured human umbilical cord mesenchymal stem cell secretome can significantly accelerate the skin wound healing rate and wound skin structure remodeling in mice.These results indicate that three-dimensional culture can enhance the expression of paracrine factors of human umbilical cord mesenchymal stem cells,and their secretome can significantly promote the repair of mouse skin damage.

BACKGROUND:The mesenchymal stem cell secretome contains bioactive substances,cytokines,and growth factors.Three-dimensional cell culture can regulate the secretion of these components,potentially enhancing the ability to promote injury repair.OBJECTIVE:To investigate the repair effect of three-dimensional cultured human umbilical cord mesenchymal stem cell secretome on skin injuries in mice.METHODS:Human umbilical cord mesenchymal stem cells were cultured in conventional two-dimensional culture dishes and 96-well U-bottom cell culture plates,from which their secretory components were subsequently collected.The expression of skin damage repair related secretory factors in umbilical cord mesenchymal stem cells was analyzed using RT-qPCR.The protein expression level of skin damage repair related factors in umbilical cord mesenchymal stem cell secretome was detected using enzyme-linked immunosorbent assay.The potential of human umbilical cord mesenchymal stem cell secretome to repair vascular injuries was evaluated using an immortalized human umbilical vein endothelial cell migration model.A mouse skin injury model was established,and the human umbilical cord mesenchymal stem cell secretome was injected subcutaneously.Repair effects on skin injury were assessed through wound healing rates and histopathological analysis.RESULTS AND CONCLUSION:(1)After three days of cultivation,human umbilical cord mesenchymal stem cells cultured in two dimensions exhibited a fibroblast-like,swirling growth pattern,whereas three-dimensional culture led to the formation of uniform microspheres.(2)Compared with two-dimensional culture,three-dimensional culture significantly increased the mRNA expression of transforming growth factor β and basic fibroblast growth factor in human umbilical cord mesenchymal stem cells.(3)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly enhanced the protein expression of vascular endothelial growth factor,interleukin-10,and granulocyte-macrophage colony-stimulating factor in the human umbilical cord mesenchymal stem cell secretome.(4)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly promoted the migration of immortalized human umbilical cord mesenchymal stem cells.(5)Compared with the untreated control group and the two-dimensional cultured human umbilical cord mesenchymal stem cell secretome,the three-dimensional cultured human umbilical cord mesenchymal stem cell secretome can significantly accelerate the skin wound healing rate and wound skin structure remodeling in mice.These results indicate that three-dimensional culture can enhance the expression of paracrine factors of human umbilical cord mesenchymal stem cells,and their secretome can significantly promote the repair of mouse skin damage.

Objective To investigate the anti-inflammatory properties of bergaptenand its inhibition of bone resorption in the treatment of periodontitis,as well as its potential underlying mechanisms.Methods A total of 35 male Wistar rats were randomly di-vided into five groups(control group,model group,and low-,medium-,and high-dose bergapten groups,with 7 rats in each group).Except for the control group,periodontitis was induced in all other groups by orthodontic ligation of the bilateral maxillary first molars(M1)and feeding a high-sugar diet.After successful modeling,the control and model groups received gavage of isotonic saline,while the bergapten groups received gavage of 50,100,and 200 mg/kg bergapten,respectively,once daily for 4 consecutive weeks.Perio-dontal symptoms were observed,and GI,SBI grades,and PLI scores were recorded.Rats were sacrificed within 24 hours after the last administration,and their maxillae were immediately subjected to Micro-CT scanning to assess alveolar bone resorption.Histopathological changes in the periodontal tissues were observed using HE staining,and serum levels of pro-inflammatory cytokines(IL-6 and IL-1β)were measured by ELISA.Results Compared with the control group,the model group exhibited significantly higher levels of IL-6,IL-1β,GI,SBI grades,PLI scores,and CEJ-ABC distance,while bone volume to total volume ratio(BV/TV),trabec-ular number(Tb.N),and trabecular thickness(Tb.Th)were significantly reduced(P＜0.001).In comparison to the model group,the bergapten groups(with the exception of the low-dose group for IL-6)demonstrated reductions in IL-6,IL-1β levels,GI,SBI grades,PLI scores,and CEJ-ABC distance,with the medium-dose group showing the most pronounced effect(except for IL-6).Conclusion Bergapten can effectively prevent and treat periodontitis by inhibiting the secretion of IL-6 and IL-1β cytokines,achieving anti-inflam-matory effects and inhibiting bone resorption.

BACKGROUND:Static stretching effectively improves joint motion amplitude,dynamic stretching effectively improves muscle strength and athletic performance through the post-activation strengthening effect of the muscles.OBJECTIVE:To explore the immediate effects of different stretching methods on knee joint muscle strength and vertical jump performance,and provide theoretical support for seeking the best stretching plan,improving sports performance,and preventing training injuries.METHODS:Thirty healthy college students were randomly recruited.The Biodex isokinetic muscle strength system,Qualisys infrared motion capture system,and AMTI three-dimensional force measurement platform were used to collect knee joint muscle strength and vertical jump data after static quadriceps/hamstring stretching,dynamic quadriceps/hamstring stretching,dynamic quadriceps/static hamstring stretching,and static quadriceps/dynamic hamstring stretching.The peak torque,average power,vertical jump height,peak vertical ground reaction force,and joint motion amplitude of the knee joint were used to evaluate the muscle strength and vertical jump performance of the knee joint.RESULTS AND CONCLUSION:Compared with the static quadriceps/hamstring stretching,dynamic quadriceps/hamstring stretching significantly increased knee joint peak torque,average power,and vertical jump height(P<0.05);dynamic quadriceps/static hamstring stretching and static quadriceps/dynamic hamstring stretching significantly increased knee extension and flexion peak torque and average power(P<0.05).Compared with static quadriceps/hamstring stretching,second peak vertical ground reaction force significantly decreased after static quadriceps/dynamic hamstring stretching(P<0.05);lower limb joint motion amplitude significantly increased after dynamic quadriceps/hamstring stretching(P<0.05).These findings indicate that immediate agonists/antagonistic muscle dynamic stretching and agonists dynamic stretching/antagonistic muscle static stretching significantly improve knee joint muscle strength,vertical jump performance,and joint motion amplitude.A larger joint motion amplitude is beneficial for improving athletic performance and better absorbing ground impact during landing.At the same time,agonists muscle dynamic stretching/antagonistic muscle static stretching is better than agonists/antagonistic muscle dynamic stretching to improve knee joint muscle strength,and agonists muscle static stretching/antagonistic muscle dynamic stretching is beneficial for improving the energy absorption capacity during vertical jumping and reducing the risk of injury during landing.

BACKGROUND:Static stretching effectively improves joint motion amplitude,dynamic stretching effectively improves muscle strength and athletic performance through the post-activation strengthening effect of the muscles.OBJECTIVE:To explore the immediate effects of different stretching methods on knee joint muscle strength and vertical jump performance,and provide theoretical support for seeking the best stretching plan,improving sports performance,and preventing training injuries.METHODS:Thirty healthy college students were randomly recruited.The Biodex isokinetic muscle strength system,Qualisys infrared motion capture system,and AMTI three-dimensional force measurement platform were used to collect knee joint muscle strength and vertical jump data after static quadriceps/hamstring stretching,dynamic quadriceps/hamstring stretching,dynamic quadriceps/static hamstring stretching,and static quadriceps/dynamic hamstring stretching.The peak torque,average power,vertical jump height,peak vertical ground reaction force,and joint motion amplitude of the knee joint were used to evaluate the muscle strength and vertical jump performance of the knee joint.RESULTS AND CONCLUSION:Compared with the static quadriceps/hamstring stretching,dynamic quadriceps/hamstring stretching significantly increased knee joint peak torque,average power,and vertical jump height(P<0.05);dynamic quadriceps/static hamstring stretching and static quadriceps/dynamic hamstring stretching significantly increased knee extension and flexion peak torque and average power(P<0.05).Compared with static quadriceps/hamstring stretching,second peak vertical ground reaction force significantly decreased after static quadriceps/dynamic hamstring stretching(P<0.05);lower limb joint motion amplitude significantly increased after dynamic quadriceps/hamstring stretching(P<0.05).These findings indicate that immediate agonists/antagonistic muscle dynamic stretching and agonists dynamic stretching/antagonistic muscle static stretching significantly improve knee joint muscle strength,vertical jump performance,and joint motion amplitude.A larger joint motion amplitude is beneficial for improving athletic performance and better absorbing ground impact during landing.At the same time,agonists muscle dynamic stretching/antagonistic muscle static stretching is better than agonists/antagonistic muscle dynamic stretching to improve knee joint muscle strength,and agonists muscle static stretching/antagonistic muscle dynamic stretching is beneficial for improving the energy absorption capacity during vertical jumping and reducing the risk of injury during landing.

BACKGROUND:Previous studies have indicated that cathepsin K can intervene with the occurrence and development of osteoporosis by regulating bone mineral density in middle-aged and older adults. However,whether there is a causal relationship between the cathepsin family and bone mineral density in other populations remains unknown. OBJECTIVE:To investigate the causal relationship between cathepsin and bone mineral density.METHODS:Genetic loci associated with eight cathepins were extracted from the IEU Open GWAS database as instrumental variables,and bone mineral density values in five age groups acted as an outcome. The causal relationship between cathepin and bone mineral density was assessed by two-way Mendelian randomization analysis. Heterogeneity of the genetic instrumental variables was assessed using Cochran's Q test,pleiotropy was assessed using the MR-Egger intercept test,and the sensitivity of single nucleotide polymorphisms used as instrumental variables to the causal effect of exposure and outcome was assessed using the leave-one-out method. RESULTS AND CONCLUSION:The results of the inverse variance weighting method with positive Mendelian randomization showed that cathepin H was negatively associated with bone mineral density in people aged 45-60 years[odds ratio (95％ confidence interval)=0.965(0.94-0.99),P=0.04];cathepin Z was negatively associated with bone mineral density in people aged 30-45 year[odds ratio (95％ confidence interval)=1.06 (1.00-1.11),P=0.03]. The results of sensitivity analysis showed a stable causal relationship,and MR-Egger intercept analysis did not detect potential horizontal pleiotropy. The inverse Mendelian randomization results showed that bone mineral density had no significant inverse effect on cathepin. The above results confirm that cathepin can affect bone mineral density in some age groups,which may increase the risk of osteoporosis and should be given more attention.

Objective To investigate the anti-inflammatory properties of bergaptenand its inhibition of bone resorption in the treatment of periodontitis,as well as its potential underlying mechanisms.Methods A total of 35 male Wistar rats were randomly di-vided into five groups(control group,model group,and low-,medium-,and high-dose bergapten groups,with 7 rats in each group).Except for the control group,periodontitis was induced in all other groups by orthodontic ligation of the bilateral maxillary first molars(M1)and feeding a high-sugar diet.After successful modeling,the control and model groups received gavage of isotonic saline,while the bergapten groups received gavage of 50,100,and 200 mg/kg bergapten,respectively,once daily for 4 consecutive weeks.Perio-dontal symptoms were observed,and GI,SBI grades,and PLI scores were recorded.Rats were sacrificed within 24 hours after the last administration,and their maxillae were immediately subjected to Micro-CT scanning to assess alveolar bone resorption.Histopathological changes in the periodontal tissues were observed using HE staining,and serum levels of pro-inflammatory cytokines(IL-6 and IL-1β)were measured by ELISA.Results Compared with the control group,the model group exhibited significantly higher levels of IL-6,IL-1β,GI,SBI grades,PLI scores,and CEJ-ABC distance,while bone volume to total volume ratio(BV/TV),trabec-ular number(Tb.N),and trabecular thickness(Tb.Th)were significantly reduced(P＜0.001).In comparison to the model group,the bergapten groups(with the exception of the low-dose group for IL-6)demonstrated reductions in IL-6,IL-1β levels,GI,SBI grades,PLI scores,and CEJ-ABC distance,with the medium-dose group showing the most pronounced effect(except for IL-6).Conclusion Bergapten can effectively prevent and treat periodontitis by inhibiting the secretion of IL-6 and IL-1β cytokines,achieving anti-inflam-matory effects and inhibiting bone resorption.

This paper used the Experimental Teaching Management Center as an example to explore the transformation practices of experimental technicians in job responsibilities, team structure, teaching and research capabilities, performance mechanisms, and collaborative education systems. The article systematically analyzed the advantages of the experimental technical team in resource openness, technical support, large instrument management, and multi-team collaboration, and summarized the practical performance through data on project approvals, competition awards, research achievements, and student growth. Additionally, it identified key challenges, including insufficient training, incomplete incentive mechanisms, and the need for improved resource coordination. To address these challenges, the study recommends the continuous enhancement of personnel capacity building, the reform of assessment systems, and the reinforcement of cross-departmental collaboration. This study provides a reference for medical schools to construct the practical path of experimental technical teams participating in the cultivation of innovative and entrepreneurial talents.

Liver cancer has high prevalence and mortality rates around the world， and its development and progression are closely associated with the interaction between the tumor microenvironment and tumor-associated macrophages （TAMs）. TAMs play a significant role in immune suppression， immune escape， cell proliferation， invasion， metastasis， and drug resistance in liver cancer. Traditional Chinese medicine （TCM）， with its unique therapeutic concepts and methods， has shown great potential in regulating TAMs and improving the prognosis of liver cancer. This article reviews the role and molecular mechanisms of TCM in regulating TAMs for the treatment of liver cancer， discusses the key role of TAMs in the progression of liver cancer， and analyzes the impact of Chinese medicinal components on the recruitment， polarization， and activity of TAMs and the expression of related factors based on TCM theory. Studies have shown that TCM can regulate the polarization state of TAMs， promote the formation of M1-type antitumor macrophages， and inhibit the activity of M2-type tumor macrophages， thereby playing a role in inhibiting the proliferation of liver cancer cells， promoting apoptosis， inhibiting angiogenesis， and enhancing immune response. In addition， this article also summarizes the molecular targets and mechanisms of action of TCM monomers， compound prescriptions， and novel preparations in the treatment of liver cancer， such as inhibiting the secretion of cytokines by TAMs， regulating signaling pathways， and affecting metabolic pathways， in order to provide a scientific basis for the application of TCM in liver cancer treatment and offer new ideas for immunotherapy for liver cancer.

As a complex autoimmune disease， rheumatoid arthritis （RA） involves immune microenvironment dysregulation resulting from excessive activation of pyroptosis， which is a crucial factor in disease progression. Based on the theory of ying-wei in traditional Chinese medicine， "ying decline and wei attack" is considered the fundamental pathogenesis of RA. Pyroptosis serves as a microscopic manifestation of this concept， suggesting a potential correlation between "ying decline and wei attack" and pyroptosis nd immune microenvironment dysregulation in RA. Accordingly， treatment principles based on this theory are proposed： in the early stage of the disease， boosting wei to consolidate the exterior， and regulating ying to dispel pathogens； in the middle and late stages， harmonizing ying to remove stagnation， and nourishing its transformational source.