Objective: To investigate the efficacy of magnesium-strontium co-doped hydroxyapatite mineralized collagen (MSHA/Col) in improving the bone repair microenvironment and enhancing bone regeneration capacity, providing a strategy to address the insufficient biomimetic composition and limited bioactivity of traditional hydroxyapatite mineralized collagen (HA/Col) scaffolds. Methods: A high-molecular-weight polyacrylic acid-stabilized amorphous calcium magnesium strontium phosphate precursor (HPAA/ACMSP) was prepared. Its morphology and elemental distribution were characterized by high-resolution transmission electron microscopy (TEM) and energy-dispersive spectroscopy. Recombinant collagen sponge blocks were immersed in the HPAA/ACMSP mineralization solution. Magnesium-strontium co-doped hydroxyapatite was induced to deposit within collagen fibers (experimental group: MSHA/Col; control group: HA/Col). The morphological characteristics of MSHA/Col were observed using scanning electron microscopy (SEM). Its crystal structure and chemical composition were analyzed by X-ray diffraction and Fourier transform infrared spectroscopy, respectively. The mineral phase content was evaluated by thermogravimetric analysis. The scaffold's porosity, ion release, and in vitro degradation performance were also determined. For cytological experiments, CCK-8 assay, live/dead cell staining, alkaline phosphatase staining, alizarin red S staining, RT-qPCR, and western blotting were used to evaluate the effects of the MSHA/Col scaffold on the proliferation, viability, early osteogenic differentiation activity, late mineralization capacity, and gene and protein expression levels of key osteogenic markers [runt-related transcription factor 2 (Runx2), collagen type Ⅰ (Col-Ⅰ), osteopontin (Opn), and osteocalcin (Ocn)] in mouse embryonic osteoblast precursor cells (MC3T3-E1). Results: HPAA/ACMSP appeared as amorphous spherical nanoparticles under TEM, with energy spectrum analysis showing uniform distribution of carbon, oxygen, calcium, phosphorus, magnesium, and strontium elements. SEM results of MSHA/Col indicated successful complete intrafibrillar mineralization. Elemental analysis showed the mass fractions of magnesium and strontium were 0.72% (matching the magnesium content in natural bone) and 2.89%, respectively. X-ray diffraction revealed characteristic peaks of hydroxyapatite crystals (25.86°, 31°-34°). Infrared spectroscopy results showed characteristic absorption peaks for both collagen and hydroxyapatite. Thermogravimetric analysis indicated a mineral phase content of 78.29% in the material. The scaffold porosity was 91.6% ± 1.1%, close to the level of natural bone tissue. Ion release curves demonstrated sustained release behavior for both magnesium and strontium ions. The in vitro degradation rate matched the ingrowth rate of new bone tissue. Cytological experiments showed that MSHA/Col significantly promoted MC3T3-E1 cell proliferation (130% increase in activity at 72 h, P < 0.001). MSHA/Col exhibited excellent efficacy in promoting osteogenic differentiation, significantly upregulating the expression of osteogenesis-related genes and proteins (Runx2, Col-Ⅰ, Opn, Ocn) (P < 0.01). Conclusion The MSHA/Col scaffold achieves dual biomimicry of natural bone in both composition and structure, and effectively promotes osteogenic differentiation at the genetic and protein levels, breaking through the functional limitations of pure hydroxyapatite mineralized collagen. This provides a new strategy for the development of functional bone repair materials

ObjectiveTo investigate the effect and mechanism of transplantation of human umbilical cord mesenchymal stem cell （hUC-MSC） with overexpression of the Numb gene in the treatment of cholestatic liver fibrosis （CLF）. MethodsThe technique of lentiviral transfection was used to induce the overexpression of the Numb gene in hUC-MSC （hUC-MSC^Numb-OE）， and hUC-MSC transfected with empty vector （hUC-MSC^OE-EV） was used as negative control. Bile duct ligation （BDL） was performed to establish a rat model of CLF， and then the rats were randomly divided into BDL group， hUC-MSC group， hUC-MSC^OE-EV group， and hUC-MSC^Numb-OE group， while a sham-operation group was also established. The rats in the intervention groups were given a single splenic injection of the corresponding cells after BDL， and samples were collected at the end of week 4. Related indicators were measured， including serum biochemistry， liver histopathology， the content of hydroxyproline （Hyp） in the liver， hepatic stellate cell activation， ductular reaction， liver regeneration， and the expression levels of key molecules in the Numb-p53 signaling axis. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for further comparison between two groups. ResultsCompared with the BDL group， the hUC-MSC group and the hUC-MSC^OE-EV group had significant reductions in the levels of serum biochemical parameters （aspartate aminotransferase， gamma-glutamyl transpeptidase， total bile acid， total bilirubin， and direct bilirubin）， liver fibrosis markers （the content of Hyp and the expression levels of alpha-smooth muscle actin， tumor necrosis factor-α， and transforming growth factor-beta 1）， and ductular reaction markers （the expression levels of CK7 and CK19） （all P <0.05）， and compared with the hUC-MSC^OE-EV group， the hUC-MSC^Numb-OE group had significantly greater improvements in the above indicators （all P <0.05）. In addition， compared with the hUC-MSC^OE-EV group， the hUC-MSC^Numb-OE group had significant improvements in the expression levels of liver regeneration-related markers （albumin and hepatocyte nuclear factor 4α） and the molecules associated with the Numb-p53 signaling axis （Numb， pNumb， Mdm2， and p53） （all P <0.05）. ConclusionOverexpression of the Numb gene can enhance the therapeutic effect of hUC-MSC on CLF， possibly by activating the Numb-PTB^L-p53-HNF4α axis， promoting the hepatic differentiation of hUC-MSCs and subsequently enhancing liver regeneration.

BACKGROUND:Research has found that human umbilical cord blood platelet rich plasma and human umbilical cord blood derived mesenchymal stem cells have certain therapeutic effects on thin endometrium.However,there are currently no reports on the study of human umbilical cord blood mononuclear cells on thin endometrium,and there is a lack of relevant research comparing the three.OBJECTIVE:To explore the effects and mechanisms of human umbilical cord blood platelet rich plasma,monocytes,and mesenchymal stem cells in repairing thin endometrium in rats.METHODS:Sixty female SPF grade SD rats were randomly divided into sham operation group,model group,human umbilical cord blood platelet rich plasma group,human umbilical cord blood mononuclear cell group,and human umbilical cord blood derived mesenchymal stem cell group,with 12 rats in each group.The sham operation group received 0.5 mL physiological saline injection into the uterine horn,followed by 0.5 mL of PBS infusion after 5 minutes;The model group,human umbilical cord blood platelet rich plasma group,human umbilical cord blood mononuclear cell group,and human umbilical cord blood derived mesenchymal stem cell group were injected with 0.5 mL of 95％ethanol by volume.After 5 minutes,the remaining ethanol was aspirated and washed twice with physiological saline.Then,0.5 mL of PBS,human umbilical cord blood platelet rich plasma,human umbilical cord blood mononuclear cells(1×107 cells/mL),and human umbilical cord blood derived mesenchymal stem cells(1×107 cells/mL)were perfused separately.During the third normal estrus cycle after reperfusion,organs,tissues and serum were collected for testing of relevant indicators.RESULTS AND CONCLUSION:(1)The macroscopic view of uterine tissue,hematoxylin eosin staining and Masson staining results:the sham operation group had intact structure,moderate endometrial thickness,and clear vascular structure.Compared with the sham operation group,the model group showed uterine atrophy,incomplete structure,significantly reduced endometrial thickness and glandular quantity,disordered vascular structure,and increased fibrosis.Compared with the model group,after treatment with human umbilical cord blood derivatives,the size,structure,and endometrial thickness of the uterus were restored(all P＜0.01),and fibrosis was reduced,with the most significant recovery observed in the human umbilical cord blood mononuclear cell group.The increase in glandular quantity was most significant in the human umbilical cord blood platelet rich plasma group(P＜0.000 1).(2)The immunohistochemistry and immunofluorescence results of uterine tissue showed that compared with the sham operation group,the expression levels of cell proliferation related indicators such as keratin 9 and vimentin,endometrial receptivity related indicators such as leukemia inhibitory factor and integrin αyβ3,platelet endothelial cell adhesion molecule,basic fibroblast growth factor,and vascular endothelial growth factor were all reduced in the model group(all P＜0.05).Compared with the model group,the above indicators were significantly increased after treatment with human umbilical cord blood derivatives.Comparison of human umbilical cord blood derivatives among groups showed that keratin 9 and vascular endothelial growth factor protein:human umbilical cord blood mononuclear cell group＞human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood platelet rich plasma group;Wave shaped protein and leukemia inhibitory factor protein:human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood mononuclear cell group＞human umbilical cord blood platelet rich plasma group;Integrin αyβ3 protein:human umbilical cord blood platelet rich plasma group＞human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood mononuclear cell group;Platelet endothelial cell adhesion molecule protein:human umbilical cord blood platelet rich plasma group＞human umbilical cord blood mononuclear cell group＞human umbilical cord blood derived mesenchymal stem cell group;Basic fibroblast growth factor protein:human umbilical cord blood mononuclear cell group＞human umbilical cord blood platelet rich plasma group＞human umbilical cord blood derived mesenchymal stem cell group.(3)Western blot analysis showed that compared with the sham operation group,the protein levels of interleukin-6,interleukin-1β,and tumor necrosis factor alpha in the model group were significantly increased(all P＜0.001),and their expression levels decreased after treatment(all P＜0.05).(4)ELISA assay showed that compared with the sham operation group,the model group had lower levels of anti Mullerian hormone,estradiol,and progesterone,and increased levels of follicle stimulating hormone and luteinizing hormone(except for luteinizing hormone,all P＜0.05).After treatment,there was a certain degree of recovery in the levels of sex hormones and anti Mullerian hormones.(5)Fertility experiments showed that compared with the sham operation group,the model group had an increase in conception time and a significant decrease in litter size(all P＜0.05).After treatment with human umbilical cord blood derivatives,the litter size of all three groups increased(P＜0.05),and no significant differences were found between the groups.This study preliminarily reveals that human umbilical cord blood mononuclear cells have a certain therapeutic effect on thin endometrium,and human umbilical cord blood platelet rich plasma,human umbilical cord blood mononuclear cells,and human umbilical cord blood derived mesenchymal stem cells have different advantages and differences in improving endometrial regeneration function,endometrial receptivity,angiogenesis,inflammation regulation,and improving pregnancy outcomes in thin endometrium.

BACKGROUND:Promoting skin wound healing is a huge challenge facing global public health.To promote faster and higher-quality wound healing,it is necessary to explore more advantageous dressings to address this problem.OBJECTIVE:To investigate the hemostatic properties of acellular dermal matrix hydrogel and its effect on skin wound healing.METHODS:(1)Acellular dermal matrix hydrogel was prepared,and the differences in microscopic morphology and main components between it and acellular dermal matrix were analyzed.(2)Acellular dermal matrix hydrogel and chitosan hydrogel were used to cover the femoral artery puncture site of rats,and the bleeding quality and coagulation time were recorded.Acellular dermal matrix hydrogel and chitosan hydrogel were mixed with rat anticoagulated blood,and the coagulation index within 30 minutes was detected.(3)A full-thickness skin defect model with a diameter of 12 mm was made on the back of 18 SD rats,and they were randomly divided into 3 groups,with 6 rats in each group:the model group used PBS to clean the wound,and the control group and the experimental group used chitosan hydrogel and acellular dermal matrix hydrogel to cover the wound,respectively.The hydrogel dressing was changed every day,and the treatment was continued for 14 days,and the wound healing was observed.On day 3 after modeling,immunofluorescence staining of inducible nitric oxide synthase(M1 macrophages)and CD206(M2 macrophages)was performed on the wound surface.On day 14 after modeling,hematoxylin-eosin staining,Masson staining,and CD31 immunohistochemical staining were performed on the wound surface.RESULTS AND CONCLUSION:(1)Scanning electron microscopy revealed that the acellular dermal matrix hydrogel had a porous structure,and the Fourier transform infrared spectrum showed that it had the same main components as the acellular dermal matrix.(2)Both acellular dermal matrix hydrogel and chitosan hydrogel had obvious hemostatic ability in vivo.In the in vitro coagulation experiments,the coagulation index of acellular dermal matrix hydrogel was significantly higher than that of chitosan hydrogel.(3)In the rat skin full-thickness defect model,both acellular dermal matrix hydrogel and chitosan hydrogel could improve the wound healing rate.Hematoxylin-eosin and Masson staining results showed that acellular dermal matrix hydrogel could reduce the infiltration of inflammatory cells in the center of the wound.Both acellular dermal matrix hydrogel and chitosan hydrogel could decrease scar width and increase collagen deposition rate.CD31 immunohistochemical staining results showed that both hydrogels could promote angiogenesis in the wound site.Immunofluorescence staining results showed that both hydrogels could reduce the proportion of M1 macrophages and increase the proportion of M2 macrophages,and the effect of acellular dermal matrix hydrogel was stronger than that of chitosan hydrogel.(4)The results show that the acellular dermal matrix hydrogel has good hemostatic properties and the ability to promote wound healing.

BACKGROUND:Research has found that human umbilical cord blood platelet rich plasma and human umbilical cord blood derived mesenchymal stem cells have certain therapeutic effects on thin endometrium.However,there are currently no reports on the study of human umbilical cord blood mononuclear cells on thin endometrium,and there is a lack of relevant research comparing the three.OBJECTIVE:To explore the effects and mechanisms of human umbilical cord blood platelet rich plasma,monocytes,and mesenchymal stem cells in repairing thin endometrium in rats.METHODS:Sixty female SPF grade SD rats were randomly divided into sham operation group,model group,human umbilical cord blood platelet rich plasma group,human umbilical cord blood mononuclear cell group,and human umbilical cord blood derived mesenchymal stem cell group,with 12 rats in each group.The sham operation group received 0.5 mL physiological saline injection into the uterine horn,followed by 0.5 mL of PBS infusion after 5 minutes;The model group,human umbilical cord blood platelet rich plasma group,human umbilical cord blood mononuclear cell group,and human umbilical cord blood derived mesenchymal stem cell group were injected with 0.5 mL of 95％ethanol by volume.After 5 minutes,the remaining ethanol was aspirated and washed twice with physiological saline.Then,0.5 mL of PBS,human umbilical cord blood platelet rich plasma,human umbilical cord blood mononuclear cells(1×107 cells/mL),and human umbilical cord blood derived mesenchymal stem cells(1×107 cells/mL)were perfused separately.During the third normal estrus cycle after reperfusion,organs,tissues and serum were collected for testing of relevant indicators.RESULTS AND CONCLUSION:(1)The macroscopic view of uterine tissue,hematoxylin eosin staining and Masson staining results:the sham operation group had intact structure,moderate endometrial thickness,and clear vascular structure.Compared with the sham operation group,the model group showed uterine atrophy,incomplete structure,significantly reduced endometrial thickness and glandular quantity,disordered vascular structure,and increased fibrosis.Compared with the model group,after treatment with human umbilical cord blood derivatives,the size,structure,and endometrial thickness of the uterus were restored(all P＜0.01),and fibrosis was reduced,with the most significant recovery observed in the human umbilical cord blood mononuclear cell group.The increase in glandular quantity was most significant in the human umbilical cord blood platelet rich plasma group(P＜0.000 1).(2)The immunohistochemistry and immunofluorescence results of uterine tissue showed that compared with the sham operation group,the expression levels of cell proliferation related indicators such as keratin 9 and vimentin,endometrial receptivity related indicators such as leukemia inhibitory factor and integrin αyβ3,platelet endothelial cell adhesion molecule,basic fibroblast growth factor,and vascular endothelial growth factor were all reduced in the model group(all P＜0.05).Compared with the model group,the above indicators were significantly increased after treatment with human umbilical cord blood derivatives.Comparison of human umbilical cord blood derivatives among groups showed that keratin 9 and vascular endothelial growth factor protein:human umbilical cord blood mononuclear cell group＞human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood platelet rich plasma group;Wave shaped protein and leukemia inhibitory factor protein:human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood mononuclear cell group＞human umbilical cord blood platelet rich plasma group;Integrin αyβ3 protein:human umbilical cord blood platelet rich plasma group＞human umbilical cord blood derived mesenchymal stem cell group＞human umbilical cord blood mononuclear cell group;Platelet endothelial cell adhesion molecule protein:human umbilical cord blood platelet rich plasma group＞human umbilical cord blood mononuclear cell group＞human umbilical cord blood derived mesenchymal stem cell group;Basic fibroblast growth factor protein:human umbilical cord blood mononuclear cell group＞human umbilical cord blood platelet rich plasma group＞human umbilical cord blood derived mesenchymal stem cell group.(3)Western blot analysis showed that compared with the sham operation group,the protein levels of interleukin-6,interleukin-1β,and tumor necrosis factor alpha in the model group were significantly increased(all P＜0.001),and their expression levels decreased after treatment(all P＜0.05).(4)ELISA assay showed that compared with the sham operation group,the model group had lower levels of anti Mullerian hormone,estradiol,and progesterone,and increased levels of follicle stimulating hormone and luteinizing hormone(except for luteinizing hormone,all P＜0.05).After treatment,there was a certain degree of recovery in the levels of sex hormones and anti Mullerian hormones.(5)Fertility experiments showed that compared with the sham operation group,the model group had an increase in conception time and a significant decrease in litter size(all P＜0.05).After treatment with human umbilical cord blood derivatives,the litter size of all three groups increased(P＜0.05),and no significant differences were found between the groups.This study preliminarily reveals that human umbilical cord blood mononuclear cells have a certain therapeutic effect on thin endometrium,and human umbilical cord blood platelet rich plasma,human umbilical cord blood mononuclear cells,and human umbilical cord blood derived mesenchymal stem cells have different advantages and differences in improving endometrial regeneration function,endometrial receptivity,angiogenesis,inflammation regulation,and improving pregnancy outcomes in thin endometrium.

BACKGROUND:Promoting skin wound healing is a huge challenge facing global public health.To promote faster and higher-quality wound healing,it is necessary to explore more advantageous dressings to address this problem.OBJECTIVE:To investigate the hemostatic properties of acellular dermal matrix hydrogel and its effect on skin wound healing.METHODS:(1)Acellular dermal matrix hydrogel was prepared,and the differences in microscopic morphology and main components between it and acellular dermal matrix were analyzed.(2)Acellular dermal matrix hydrogel and chitosan hydrogel were used to cover the femoral artery puncture site of rats,and the bleeding quality and coagulation time were recorded.Acellular dermal matrix hydrogel and chitosan hydrogel were mixed with rat anticoagulated blood,and the coagulation index within 30 minutes was detected.(3)A full-thickness skin defect model with a diameter of 12 mm was made on the back of 18 SD rats,and they were randomly divided into 3 groups,with 6 rats in each group:the model group used PBS to clean the wound,and the control group and the experimental group used chitosan hydrogel and acellular dermal matrix hydrogel to cover the wound,respectively.The hydrogel dressing was changed every day,and the treatment was continued for 14 days,and the wound healing was observed.On day 3 after modeling,immunofluorescence staining of inducible nitric oxide synthase(M1 macrophages)and CD206(M2 macrophages)was performed on the wound surface.On day 14 after modeling,hematoxylin-eosin staining,Masson staining,and CD31 immunohistochemical staining were performed on the wound surface.RESULTS AND CONCLUSION:(1)Scanning electron microscopy revealed that the acellular dermal matrix hydrogel had a porous structure,and the Fourier transform infrared spectrum showed that it had the same main components as the acellular dermal matrix.(2)Both acellular dermal matrix hydrogel and chitosan hydrogel had obvious hemostatic ability in vivo.In the in vitro coagulation experiments,the coagulation index of acellular dermal matrix hydrogel was significantly higher than that of chitosan hydrogel.(3)In the rat skin full-thickness defect model,both acellular dermal matrix hydrogel and chitosan hydrogel could improve the wound healing rate.Hematoxylin-eosin and Masson staining results showed that acellular dermal matrix hydrogel could reduce the infiltration of inflammatory cells in the center of the wound.Both acellular dermal matrix hydrogel and chitosan hydrogel could decrease scar width and increase collagen deposition rate.CD31 immunohistochemical staining results showed that both hydrogels could promote angiogenesis in the wound site.Immunofluorescence staining results showed that both hydrogels could reduce the proportion of M1 macrophages and increase the proportion of M2 macrophages,and the effect of acellular dermal matrix hydrogel was stronger than that of chitosan hydrogel.(4)The results show that the acellular dermal matrix hydrogel has good hemostatic properties and the ability to promote wound healing.

ObjectiveTo evaluate the predictive value of epicardial adipose tissue （EAT） parameters for microvascular obstruction （MVO） formation in patients with ST segment elevation myocardial infarction （STEMI） using cardiac magnetic resonance quantification. MethodsA total of 139 STEMI patients were included in this study， and various parameters such as EAT thickness， volume， and mass index were measured utilizing cardiac magnetic resonance. All included patients were divided into MVO group and non-MVO group according to whether MVO occurred. Differences in EAT related parameters between two groups were compared and correlation analysis was applied to evaluate the correlation between quantitative indicators of EAT and indicators such as infarct size and ejection fraction. Logistic regression analysis was used to identify the relevant risk factors for MVO formation. Receiver Operating Characteristic （ROC） curve analysis was performed to assess the predictive value of the epicardial adipose tissue （EAT） quality index and other indicators for the occurrence of MVO. ResultsCompared with non MVO group， patients in MVO group presented with higher peak troponin T levels， increase of neutrophil lymphocyte ratio （NLR） and C-reactive protein （CRP）， larger infarct size and compromised left ventricular ejection fraction （LVEF） （P<0.05）. Total EAT volume， EAT mass index， left atrioventricular EAT volume， left atrioventricular EAT mass index and thickness of EAT in the left atrioventricular groove were significantly higher in patients with MVO. Multivariate Logistic regression analysis demonstrated that NLR， peak troponin T levels and left atrioventricular EAT mass index were independent predictors of MVO. The ROC curve suggested that the left atrioventricular EAT mass index had the highest predictive power for MVO formation in STEMI patients. ConclusionThe parameters of EAT quantified by cardiac magnetic resonance serve as imaging biomarkers for predicting MVO formation in STEMI patients. These metrics enable risk stratification post-myocardial infarction and facilitate early identification of high-risk individuals， thereby supporting personalized therapeutic decision-making.

Objective To analyze the influencing factors of delirium after endovascular aortic repair, and to provide a basis for clinical nursing and prevention of this condition. Methods Patients who underwent endovascular aortic repair at Fuwai Hospital, Chinese Academy of Medical Sciences from 2018 to 2019 were selected. The Chinese version of the Nursing Delirium Screening Scale (Nu-DESC) was used to assess whether postoperative delirium occurred. Patients with a Nu-DESC score≥ 3 were assigned to the delirium group. Non-delirium patients who had the same surgeon and adjacent surgical order were selected at a 1 : 4 ratio to form the non-delirium group. Univariate analysis was performed on the clinical data of the two groups. Factors with P<0.1 in the univariate analysis and those considered clinically significant were included in a multivariate logistic regression analysis to identify the influencing factors of postoperative delirium. Stratified analysis was conducted based on thoracic endovascular aortic repair (TEVAR) and endovascular abdominal aortic repair (EVAR). Results A total of 213 patients were included, comprising 46 in the delirium group and 167 in the non-delirium group. The overall mean age was (60.3±12.0) years, and 183 (85.9%) were male. Univariate analysis showed that emergency admission, preoperative neutrophil percentage, aortic dissection, surgical duration, intubation time, and ICU stay may be associated with postoperative delirium. Multivariate analysis revealed that longer operative and intubation times were associated with a higher likelihood of delirium. In the stratified analysis, the results for the TEVAR group were consistent with the overall findings, whereas no significant differences were observed in the EVAR group. Conclusion Longer surgical and intubation times are associated with an increased risk of delirium in patients undergoing TEVAR. No significant factors influencing delirium are identified in patients undergoing EVAR.

BACKGROUND:Lijin manipulation can promote skeletal muscle repair and treat skeletal muscle injury.However,the formation of fibrosis and scar tissue hyperplasia are closely related to the quality of skeletal muscle repair.To study the regulatory effect of Lijin manipulation on the formation of fibrosis and scar tissue hyperplasia is helpful to explain the related mechanism of Lijin manipulation to improve the repair quality of skeletal muscle injury. OBJECTIVE:To explore the mechanism of Lijin manipulation to improve the repair quality of skeletal muscle injury in rabbits,thereby providing a scientific basis for clinical treatment. METHODS:Forty-five healthy adult Japanese large-ear white rabbits were randomly divided into blank group,model group and Lijin group,with 15 rats in each group.Gastrocnemius strike modeling was performed in both model group and Lijin group.The Lijin group began to intervene with tendon manipulation on the 3rd day after modeling,once a day,and 15 minutes at a time.Five animals in each group were killed on the 7th,14th and 21st days after modeling.The morphology and inflammatory cell count of gastrocnemius were observed by hematoxylin-eosin staining,the collagen fiber amount was observed by Masson staining,the expression of interleukin-6 and interleukin-10 in gastrocnemius was detected by ELISA.The protein and mRNA expressions of paired cassette gene 7,myogenic differentiation factor,myoblastogenin,alpha-actin,transforming growth factor beta 1,and type Ⅰ collagen were detected by western blot and RT-PCR,respectively,and the expression of type Ⅰ collagen protein was detected by immunohistochemistry. RESULTS AND CONCLUSION:Hematoxylin-eosin staining and Masson staining showed that compared with the model group,inflammatory cell infiltration and collagen fiber content decreased in the Lijin group(P<0.01),and the muscle fibers gradually healed.ELISA results showed that compared with the model group,the expression of interleukin-6 in the Lijin group continued to decrease(P<0.05),and the expression of interleukin-10 increased on the 7th day after modeling(P<0.05)and then showed a decreasing trend(P<0.05).Western blot and RT-PCR results showed that compared with the model group,the protein and mRNA expressions of paired cassette gene 7,myogenic differentiation factor,myoblastogenin in the Lijin group were significantly increased on the 14th day after modeling(P<0.05),but decreased on the 21st day(P<0.05);the protein and mRNA expressions of alpha-actin,transforming growth factor beta 1,and type Ⅰ collagen in the Lijin group were significantly decreased compared with those in the model group(P<0.05).Immunohistochemical results showed that the expression of type Ⅰ collagen in the Lijin group was significantly lower than that in the model group(P<0.05).To conclude,Lijin manipulation could improve the repair quality of skeletal muscle injury by inhibiting inflammation,promoting the proliferation and differentiation of muscle satellite cells,and reducing fibrosis.

Natural arabinogalactan， an important polysaccharide， has a wide range of sources， a complex structure， various biological activities， and great application potential. Natural arabinogalactan is mainly rich in plants and microorganisms， and its structure varies due to different sources， including types Ⅰ， type Ⅱ， type Ⅱ-related types， and new configurations. Natural arabinogalactan has shown a variety of biological activities， such as anti-tumor， anti-oxidation， anti-coagulation， anti-aging， blood glucose-lowering， intestinal health-maintaining， anti-inflammatory， and immunomodulatory activities. In addition， natural arabinogalactan shows good biocompatibility and low toxicity， serving as a potential material in the biomedical field. Natural arabinogalactan has been designed as a carrier in the drug delivery system to effectively improve drug stability and targeting. Natural arabinogalactan is often added to skin care products to help delay skin aging and enhance skin barrier function because of their moisturizing and antioxidant properties. Additionally， natural arabinogalactan acts as a thickener， stabilizer， and emulsifier to improve the texture and taste while enhancing the nutritional value of food products. The review of latest research reports is helpful to further understand the relationship between the structure， biological activity， and functional application of natural arabinogalactan and provides an important reference for future research and development.