BACKGROUND:Muscle aging is closely related to various epigenetic changes,and exercise has a certain regulatory effect on these epigenetic changes.However,the specific mechanism is not fully understood. OBJECTIVE:To review the epigenetic mechanisms of skeletal muscle and how exercise can improve skeletal muscle aging and promote adaptive changes in muscle through these epigenetic mechanisms,aiming to provide a more comprehensive understanding of skeletal muscle aging and disease mechanisms. METHODS:During the period from June 1st to August 1st,2023,literature searches were conducted for relevant literature published from database inception to August 2023 in databases including Web of Science,PubMed,CNKI,WanFang,and VIP.The search terms used included"skeletal muscle,""muscle,""aging,""older adult,""aging,""exercise,""physical exercise,""epigenetic,"and"epigenetics"in Chinese as well as"skeletal muscle,muscle,aging,older adult,senescence,age,exercise,sports,physical activity,epigenetic,epigenetics"in English.Boolean logic operators were used to connect the search terms for retrieval,and corresponding strategies were developed.According to the predetermined inclusion and exclusion criteria,70 eligible articles were selected. RESULTS AND CONCLUSION:Epigenetics refers to the phenomenon where gene expression and function are regulated without changes in gene sequence,and epigenetic changes in skeletal muscle are an important field.The epigenetic mechanisms of skeletal muscle play an important role in muscle aging,mainly involving DNA methylation,histone modification,regulation of non-coding RNAs,chromatin remodeling,changes in mitochondrial function and expression changes of aging-related genes.Exercise significantly regulates the epigenetics of skeletal muscle,including promoting DNA methylation,muscle histone modification,regulating miRNA expression,and regulating lncRNA expression,regulating muscle factors(such as interleukin-6),regulating mitochondrial function(such as peroxisome proliferators-activated receptors γ co-activator 1α).Future studies are recommended for long-term,cross-diverse population-based exercise interventions;the application of multi-omics techniques such as proteomics and metabolomics;strengthening the understanding of epigenetic changes at the single-cell level;cross-species comparative studies as well as human clinical trials for the translation of animal model findings to humans;strategies for combining exercise and pharmacological interventions to assess their synergistic effects;and epigenetic studies of crosstalk interactions between skeletal muscle and different organs.

BACKGROUND:Dysfunction of macrophage efferocytosis can induce local and systemic inflammatory damage and is associated with a variety of obesity-related metabolic diseases.Moreover,compounds targeting efferocytosis have shown good therapeutic effects. OBJECTIVE:By reviewing the effects of obesity on macrophage efferocytosis,to analyze the key mechanism by which obesity inhibits efferocytosis,to summarize the research progress in compounds targeting efferocytosis to treat obesity-related metabolic diseases,so as to provide new ideas for fully understanding efferocytosis and its relationship with metabolic diseases,aiming to provide new strategies for disease prevention and treatment. METHODS:The English search terms were"efferocytosis,metabolism,obesity,obese,atherosclerosis,non-alcoholic steatohepatitis,neurodegeneration,tumor,osteoarthritis,diabetes,compound,medicine,treatment,"which were used for literature retrieval in PubMed and Web of Science.The Chinese search term was"efferocytosis,"which was used for literature retrieval in CNKI,VIP and WanFang datebases.Ninety-nine papers were finally included in the review analysis after a rigorous screening process. RESULTS AND CONCLUSION:In the process of efferocytosis,the"Find me"and"Eat me"processes involving a large number of apoptotic cell derived factors are mainly regulated by apoptotic cells.The efferocytosis factor involved in cytoskeletal remodeling and digestion are mainly derived from macrophages,which are crucial for efferocytosis activity.These results suggest that the"Find me"and"Eat me"factors mainly reflect the condition of apoptosis,and it is more scientific to select the expression of factors involved in cytoskeletal remodeling and digestion when evaluating the efferocytosis activity of macrophages.Obesity inhibits efferocytosis,and shows an inhibitory effect on most digestive factors,but has a stress-induced activation effect on most"Find me,""Eat me"and cytoskeletal recombination factors,which further indicates the decisive effect of digestive stage on efferocytosis and suggests that it is not reliable for some studies to evaluate the efferocytosis based on the increased expression of"Find me"and"Eat me"factors.Targeting cytokines in the digestive phase may be more effective when discussing future intervention strategies targeting macrophages efferocytosis.The efferocytosis activators of macrophages are effective in the treatment of various metabolic diseases,but the efferocytosis inhibitors in tumor tissue show good anticancer effects,suggesting that the role of efferocytosis should be rationally evaluated according to the characteristics of tissue inflammation.Efferocytosis is a relatively new concept proposed in 2003,with a short research history and complex efferocytosis factors.Current studies on obesity and efferocytosis only involve a tip of the iceberg and most of them are at a superficial level and a large number of scientific experiments are needed to further validate the mechanisms.

BACKGROUND:There is still no consensus on the optimal internal fixation for the treatment of Pauwels Ⅲ femoral neck fracture,and most of the related finite element analyses have been performed using a single simplified loading condition,and the biomechanical properties of commonly used internal fixation devices need to be further investigated. OBJECTIVE:To analyze the biomechanical characteristics of Pauwels Ⅲ femoral neck fractures treated with cannulated compression screw,dynamic hip screw,and femoral neck system by finite element method under different loading conditions of single-leg standing loads and sideways fall loads. METHODS:The DICOM data of healthy adult femur were obtained by CT scanning,imported into Mimics 15.0 software to obtain the rough model of bone tissue.The data exported from Mimics were optimized by Geomagics software,and then three internal fixation models were built and assembled with the femur model according to the parameters of the clinical application of the cannulated compression screw,dynamic hip screw,and femoral neck system by using Pro/E software.Finally,the three internal fixation models were imported into Ansys software for loading and calculation to analyze the stress distribution and displacement of the femur and the internal fixation under different working conditions of single-leg standing loads and sideways fall loads,as well as the stress characteristics of the calcar femorale and Ward's triangle. RESULTS AND CONCLUSION:(1)Under the single-leg standing load and the sideways fall load,the proximal femoral stress of the three internal fixation models was mainly distributed above the fracture end of the femoral neck.The peak stress of the proximal femoral end,fracture end,Ward triangle,and calcar femorale of the three internal fixation models were the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(2)Under the single-leg standing load and the sideways fall load,the peak displacement of the proximal femur of the three internal fixation models was all located at the top of the femoral head,and the peak displacement was the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(3)The peak displacement of the three internal fixation models was all located at the top of the internal fixation device under the single-leg standing and sideways fall loading conditions,and the peak displacement values were the smallest in the femoral neck system internal fixation model and the largest in the cannulated compression screw internal fixation model.(4)The internal fixation stress of the three internal fixation models was mainly distributed in the area near the fracture end of the internal fixation device under the single-leg standing and sideways fall loads,and the peak value of internal fixation stress was the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(5)These results suggest that the mechanical stability of the femoral neck system is the best,but there may be a risk of stress shielding of the fracture end and calcar femorale.The stress of the internal fixation device of the femoral neck system is more dispersed,and the risk of internal fixation break is lower.

BACKGROUND:It has also been confirmed that ferroptosis is closely related to a variety of musculoskeletal diseases,such as rheumatoid arthritis,osteosarcoma,and osteoporosis.The pathophysiological mechanisms of ferroptosis and osteoporosis need to be further studied and elucidated to broaden our understanding of iron metabolism and osteoporosis.It will provide research ideas for the future elucidation of new mechanisms of osteoporosis and the development of new technologies and drugs for the treatment of osteoporosis. OBJECTIVE:To provide an overview of the current status of research on ferroptosis in osteoporosis,to provide a new direction for future research on the specific molecular mechanisms of osteoporosis,and to provide more effective and better options for osteoporosis treatment strategies. METHODS:The first author used the computer to search the literature published from 2000 to 2024 in CNKI,WanFang,VIP,and PubMed databases with search terms"ferroptosis,iron metabolism,osteoporosis,osteoblast,osteoclast,bone metabolism,signal pathway,musculoskeletal,review"in Chinese and English.A total of 68 articles were finally included according to the selection criteria. RESULTS AND CONCLUSION:(1)Ferroptosis is a new type of cell death discovered in recent years,which is usually accompanied by a large amount of iron accumulation and lipid peroxidation during cell death,and its occurrence is iron-dependent.This is distinctly different from several types of cell death that are currently being hotly studied(e.g.,cellular pyroptosis,necrotic apoptosis,cuproptosis,and autophagy).(2)Intracellular iron homeostasis is manifested as a balance between iron uptake,export,utilization,and storage.The body's iron regulatory system includes systemic and intracellular regulation.The main factor of systemic regulation is hepcidin produced by hepatic secretion,and cellular regulation depends on the iron regulatory protein/iron response element system.Of course,intracellular iron homeostasis can be controlled by other factors,such as hypoxia,cytokines,and hormones.(3)Lipid peroxidation causes oxidative damage to biological membranes(plasma membrane and internal organelle membranes),lipoproteins,and other lipid-containing molecules.Polyunsaturated fatty acid-containing phospholipids are important targets of lipid peroxidation.Free polyunsaturated fatty acid is an important substrate for lipid oxidation and can bind to the phospholipid bilayer,leading to over-oxidation and thus triggering lipid apoptosis.(4)Several studies have shown that osteoblasts are overloaded with iron in different ways,resulting in the accumulation of unstable ferrous iron and the generation of reactive oxygen species and lipid peroxides,causing ferroptosis of osteoblasts and ultimately a decrease in bone formation,affecting bone homeostasis and the development of osteoporosis.(5)Osteoclasts are large multinucleated cells formed by the fusion of mononuclear macrophage cell lines or bone marrow mesenchymal stem cells induced by nuclear factor-κB ligand receptor activator,and they have the function of bone resorption.Iron ions can promote osteoclast differentiation and bone resorption through the production of intracellular lipid reactive oxygen species,while iron chelators can inhibit osteoclast formation in vitro and thus affect the occurrence and development of osteoporosis.

OBJECTIVE:Anterior cervical decompression and fusion is a classic surgical method for the treatment of degenerative cervical spondylosis.The use of nail plates increases the fusion rate and stability and indirectly leads to adjacent vertebral degeneration and postoperative dysphagia.In this paper,the clinical results and complications of ROI-CTM self-locking system and traditional cage combined with screw-plate internal fixation in the treatment of degenerative cervical spondylosis were compared by meta-analysis to provide evidence-based support for the selection of internal fixation methods in anterior cervical decompression and fusion. METHODS:CNKI,WanFang,VIP,PubMed,Cochrane Library,Web of Science,and Embase databases were searched for Chinese and English literature on the application of ROI-CTM self-locking system and fusion cage combined with screw plate internal fixation in the treatment of degenerative cervical spondylosis.The retrieval time range was from inception to July 2023.Two researchers selected the literature strictly according to the inclusion and exclusion criteria.The Cochrane bias risk tool was used to evaluate the quality of randomized controlled trials.Newcastle-Ottawa Scale was used to assess the quality of cohort studies.Meta-analysis was performed using RevMan 5.4 software.Outcome indicators included operation time,intraoperative blood loss,Japanese Orthopaedic Association score,Neck Disability Index,C2-C7 Cobb angle,fusion rate,incidence of adjacent vertebral degeneration,cage subsidence rate,and incidence of dysphagia. RESULTS:Thirteen articles were included,including eleven retrospective cohort studies and two randomized controlled trials,with 1 136 patients,569 in the ROI-C group,and 567 in the cage combined with the nail plate group.Meta-analysis results showed that the operation time(MD=-15.52,95%CI:-18.62 to-12.42,P<0.000 01)and intraoperative blood loss(MD=-24.53,95%CI:-32.46 to-16.61,P<0.000 01)in the ROI-C group and the fusion device combined with nail plate group.Postoperative adjacent segment degeneration rate(RR=0.40,95%CI:0.27-0.60,P<0.000 01)and postoperative total dysphagia rate(RR=0.18,95%CI:0.13-0.26),P<0.000 01)were statistically different.The two groups had no significant difference in Japanese Orthopaedic Association score,Neck Disability Index,C2-C7 Cobb angle,fusion rate,or cage subsidence rate(P≥0.05). CONCLUSION:Applying an ROI-CTM self-locking system and traditional cage combined with plate internal fixation in anterior cervical decompression and fusion can achieve satisfactory clinical results in treating degenerative cervical spondylosis.The operation of the ROI-CTM self-locking system is more straightforward.Compared with a cage combined with plate internal fixation,the ROI-CTM self-locking system can significantly reduce the operation time and intraoperative blood loss and has obvious advantages in reducing the incidence of postoperative dysphagia and adjacent segment degeneration.The ROI-CTM self-locking system is recommended for patients with skip cervical spondylosis and adjacent vertebral disease.However,given its possible high settlement rate,using a fusion cage combined with screw-plate internal fixation is still recommended for patients with degenerative cervical spondylosis with multiple segments and high-risk factors of fusion cage settlement,such as osteoporosis and vertebral endplate damage.

BACKGROUND:Small diameter artificial vessels are urgently needed to treat coronary artery and peripheral artery diseases in clinical practice.At present,vascular tissue engineering has become the main method for preparing small diameter artificial vessels.Selecting suitable biomaterials and cell sources is the key factor for successful construction of small diameter tissue engineered vessels. OBJECTIVE:To observe the effect of four kinds of electrospinning membrane materials on proliferation,adhesion and differentiation of bone marrow mesenchymal stem cells into vascular smooth muscle cells. METHODS:Bone marrow mesenchymal stem cells were isolated and extracted from SD rats.The bone marrow mesenchymal stem cells were inoculated separately on polycaprolactone(PCL),polycaprolactone-hyaluronic acid(PCL-HA),polycaprolactone-silk-filament proteins(PCL-SF),and polycaprolactone-gelatin(PCL-GEL)electrospinning membrane materials.After 1,3,and 7 days of culture,the cell arrangement on the material was observed under scanning electron microscope.The proliferation and adhesion of the material were observed by phalloidin staining.The mRNA expressions of CD90,Meflin,and transforming growth factor β were detected by qRT-PCR.After 7 days of induced differentiation into vascular smooth muscle cells,the mRNA expression ofɑ-smooth muscle actin on the material was detected by qRT-PCR. RESULTS AND CONCLUSION:(1)Bone marrow mesenchymal stem cells were arranged along the fibers of the four kinds of electrospinning membranes under scanning electron microscopy.(2)Phalloidin staining showed the regular distribution of bone marrow mesenchymal stem cells on the four kinds of electrospinning membranes and parallel distribution along the fiber direction.Moreover,PCL-HA,PCL-SF,and PCL-GEL electrospinning membranes were more conducive to the proliferation and adhesion of bone marrow mesenchymal stem cells than PCL electrospinning membranes.Compared with PCL-HA and PCL-GEL electrospinning membranes,PCL-SF electrospinning membranes were more conducive to the proliferation and adhesion of bone marrow mesenchymal stem cells.(3)qRT-PCR showed that the four kinds of electrospun membrane materials could maintain the mRNA expression of CD90 and Meflin in bone marrow mesenchymal stem cells,but there was no significant difference between groups(P>0.05).The mRNA expression of transforming growth factor β in PCL-HA,PCL-SF,and PCL-GEL groups was higher than that in PCL group on days 1 and 7(P<0.05),and the mRNA expression of transforming growth factor β in PCL-SF group was higher than that in the other three groups on days 3 and 7(P<0.05).The mRNA expression of transforming growth factor β in PCL-HA group was higher than that in PCL-GEL group on day 7(P<0.05).(4)qRT-PCR showed that the mRNA expression of ɑ-smooth muscle actin in PCL-SF group was higher than that in the other three groups(P<0.05),and that in PCL-HA group was higher than that in PCL group(P<0.05).(5)The results indicate that compared with PCL,PCL-HA and PCL-GEL electrospinning membranes,PCL-SF electrospinning membranes combined with bone marrow mesenchymal stem cells are more suitable for the preparation of small diameter tissue engineered vessels.

BACKGROUND:Crosslinked sodium hyaluronate gel has good mechanical property,biocompatibility,and biodegradability,and can be used as an isolated protective material in tumor radiation therapy to protect endangered organs from damage caused by excess radiation dose. OBJECTIVE:To investigate the safety and efficacy of crosslinked sodium hyaluronate gel in reducing the dose of radiation to dangerous organs during brachytherapy. METHODS:A total of 16 specific pathogen-free Kunming mice of the same age and similar body weight were selected as experimental subjects and divided into experimental group and control group by the random number table method,with 8 mice in each group.125I seeds were implanted subcutaneously in the back of mice in the experimental group,and then crosslinked sodium hyaluronate gel was injected around the radioactive particles.Only 125I seeds were implanted subcutaneously in the back of mice in the control group.After injection,the distance between the radioactive particles and the epidermis was measured by spiral CT scan,and the surface radiation dose was measured by radiation dosimeter.Within 10 weeks after injection,the growth state,survival rate,skin radiation damage,and gel retention of mice were observed. RESULTS AND CONCLUSION:(1)Spiral CT scan showed that the implanted gel was relatively concentrated and created an effective distance between the radioactive seeds and the epidermis.The body surface radiation dose of the experimental group was significantly lower than that of the control group(P<0.01).(2)During the experimental observation period,mice in both groups survived;mice in the control group showed obvious irritability and other unstable behavior in the late experimental period,and some mice in the experimental group showed similar behavior.The daily food intake of mice in the two groups had no significant change,and the body mass showed the same increasing trend.After implantation of radioactive seeds,the two groups of mice showed different degrees of radioactive skin injury.From day 23 after injection to the end of the experiment,the skin radiation injury score of the experimental group was lower than that of the control group(P<0.01).At week 10 after implantation,6 mice in the experimental group had no obvious gel residue under their skin,and 2 mice had a very small amount of scattered gel-like samples under their skin.(3)Therefore,the crosslinked sodium hyaluronate injection technique can increase the space between the radioactive target area of 125I seeds and the organ at risk outside the target through physical space occupying,which can effectively reduce the dose of the organ at risk,and play a role in the isolation and protection of the organ at risk.

BACKGROUND:We have successfully established an animal model of small ear pig in southern Yunnan province with internal tension relieving technique combined with autologous Achilles tendon for anterior cruciate ligament reconstruction,and verified the stability and reliability of the model.However,whether internal tension relieving technique can promote the ligamentalization process of autologous Achilles tendon graft has not been studied. OBJECTIVE:To investigate the differences in the process of ligamentalization between conventional reconstruction and internal reduction reconstruction of the anterior cruciate ligament by gross view,histology and electron microscopy. METHODS:Thirty adult female small ear pigs in southern Yunnan province were selected.Anterior cruciate ligament reconstruction was performed on the left knee joint with the ipsilateral knee Achilles tendon(n=30 in the normal group),and anterior cruciate ligament reconstruction was performed on the right knee joint with the ipsilateral knee Achilles tendon combined with the internal relaxation and enhancement system(n=30 in the relaxation group).The autogenous right forelimb was used as the control group;the anterior cruciate ligament was exposed but not severed or surgically treated.At 12,24,and 48 weeks after surgery,10 animals were sacrificed,respectively.The left and right knee joint specimens were taken for gross morphological observation to evaluate the graft morphology.MAS score was used to evaluate the excellent and good rate of the ligament at each time point.Hematoxylin-eosin staining was used to evaluate the degree of ligament graft vascularization.Collagen fibers and nuclear morphology were observed,and nuclear morphology was scored.Ultrastructural remodeling was evaluated by scanning electron microscopy and transmission electron microscopy. RESULTS AND CONCLUSION:(1)The ligament healing shape of the relaxation group was better at various time points after surgery,and the excellent and good rate of MAS score was higher(P<0.05).Moreover,the relaxation group could obtain higher ligament vascularization score(P<0.05).(2)The arrangement of collagen bundles and fiber bundles in the two groups gradually tended to be orderly,and the transverse fiber connections between collagen gradually increased and thickened,suggesting that the strength and shape degree of the grafts were gradually improved,but the ligament remodeling in the relaxation group was always faster than that in the normal group at various time points after surgery.(3)The diameter,distribution density,and arrangement degree of collagen fibers in the relaxation group were better than those in the normal group at all time points,especially in the comparison of collagen fiber diameter between and within the relaxation group(P<0.05).

BACKGROUND:In recent years,artificial intelligence has gradually emerged and has been applied in various fields such as spinal cord nerve injury and repair,which has a positive impact on clinical treatment. OBJECTIVE:To study the application progress of artificial intelligence in the diagnosis,treatment,and rehabilitation of spinal cord nerve injury and repair,clarify the research hotspots and shortcomings in this field,and provide suggestions for future research work. METHODS:Relevant literature on artificial intelligence in the field of spinal cord nerve injury and repair was retrieved on the Web of Science core collection database until 2023.CiteSpace 6.1.R6 and VOSviewer 1.6.19 software was used to perform general literature analysis,co-citation of literature,co-citation of journals,double image overlay of journals,keyword clustering,and other visual analysis on the literature data. RESULTS AND CONCLUSION:(1)A total of 1 713 articles were selected,and the annual publication volume in this field showed a fluctuating upward trend,with the United States taking the lead,and Kadone and Hideki being the authors with the highest publication volume.ARCH PHYS MED REHAB was the journal with the highest number of citations.(2)Keyword co-occurrence and cluster analysis showed that after removing keywords similar to the search terms,the main keywords were divided into three main clusters:Exoskeleton and exercise rehabilitation(the largest core hotspot);machine learning and neural plasticity;robotics and rehabilitation training.(3)Keyword burst analysis showed that deep learning and artificial intelligence had become burst terms in the past five years.(4)The results of in-depth analysis of co cited and highly cited literature showed that the hotspots of artificial intelligence in the field of spinal cord nerve injury and repair were mainly focused on powered exoskeletons,gaits,electrical nerve stimulation,intracortical brain-computer interface(IBCI),robots,and polymer biomaterials,and neural stem cell.(5)The research on artificial intelligence in the field of spinal cord nerve injury and repair has shown an upward trend in recent years.The focus of this field had gradually shifted from single treatment methods such as exoskeletons and electrical stimulation to intelligent,precise,and personalized directions.(6)There were some limitations in this field,such as the consequences of missing or imbalanced data,low data accuracy and reproducibility,and ethical issues(such as privacy,research transparency,and clinical reliability).Future research should address the issue of data collection,requiring large sample,high-quality clinical datasets to establish effective artificial intelligence models.At the same time,the research on genomics and other mechanisms in this field is very weak.In the future,various machine learning technologies such as brain chips can be used,and gene editing therapy,single-cell spatial transcriptome and other methods can be used to study the basic mechanisms of regeneration-related gene upregulation and axon growth structural protein production.

BACKGROUND:The regulation of M1/M2 polarization direction of macrophages is particularly critical in tissue engineering applications,and timely regulation can minimize proinflammatory,anti-inflammatory,or tissue healing responses. OBJECTIVE:To implant lentivirus-mediated miRNA-378a macrophage strain complex collagen to detect the expression level of immune regulation in the in vivo environment,and further clarify the influence of miRNA-378a in promoting macrophage M2 polarization in immune regulation and tissue repair in the in vivo environment. METHODS:Lentivirus-mediated miRNA-378a overexpressing macrophage cell lines and negative control virus macrophage lines were amplified and screened,and the macrophage lines were recovered and cultured together with collagen sponge to form a composite scaffold,which was divided into the following groups:(1)Positive group:miRNA-378a overexpressing macrophage-collagen sponge composite;(2)negative group:negative control of virus-mediated miRNA-378a macrophage-collagen sponge composite;(3)control group:macrophage-collagen sponge;(4)blank control group:collagen sponge.The cell density,phenotype,and adhesion of each group were observed by immunofluorescence and scanning electron microscopy.The cells were implanted into the subcutaneous model of the back of mice,and the mice were sacrificed 4 and 7 days after modeling.The direction of macrophage polarization in the collagen sponge composite of macrophages with miRNA-378a overexpression mediated by lentivirus and its effect on immune regulation and tissue repair were analyzed by gross observation,hematoxylin-eosin staining,MASSON staining,and immunohistochemistry. RESULTS AND CONCLUSION:(1)Under immunofluorescence microscopy,the macrophage cell lines in each group were observed to form a composite scaffold with the collagen sponge.(2)Under scanning electron microscope,lentivirus-mediated miRNA-378a macrophages in the positive group proliferated in cell density,had spherical,elliptic and polygonal differentiation,and had more pseudofeet than other groups.(3)Under general observation,the overall 7-day healing was better than that at 4 days.Lentivirus-mediated miRNA-378a macrophages in the positive group healed better than other groups regardless of 4 and 7 days.(4)Lentivirus-mediated miRNA-378a macrophages in the positive group under hematoxylin-eosin staining and MASSON staining had more amounts of fibrocytes,capillaries,fibroblasts,and collagen fiber hyperplasia.(5)Immunohistochemistry showed that lentivirus-mediated miRNA-378a macrophages in the positive group were more positive in 4-and 7-day M2 polarized cells than in other groups.The macrophages of the control and negative groups in 4-and 7-day M2 polarized cells were greater than that of the blank control group.There was no statistical difference between the control group and the negative group.The number of stained cells in the positive,negative,and control groups regardless of 4 and 7 days was higher than that in the blank control group,and the positive group>negative group ≈ control group>blank control group.(6)It is concluded that macrophages with miRNA-378a overexpression have a large amount of fibroblasts,capillaries,fibroblasts,and collagen fiber hyperplasia in vivo,which has a positive effect on tissue repair,and can promote the polarization of macrophages towards M2 type and inhibit the polarization of M1 type,thus contributing to reducing the inflammatory response of the body.