ObjectiveThis study aims to investigate whether Xixintang could ameliorate cognitive dysfunction in an Alzheimer's disease （AD） rat model induced by D-galactose and β-amyloid （Aβ_25-35）， by means of repairing the colonic mucosal barrier， regulating the Toll-like receptor 4 （TLR4）/nuclear factor-κB p65 （NF-κB p65） signaling pathway， and intervening in the pathological process mediated by the gut-brain axis. MethodsSixty specific pathogen-free （SPF） male Sprague-Dawley （SD） rats were randomly divided to five groups （n=12）： A control group， a model group， a donepezil group， an Xixintang group， and a probiotic group. Except for those in the control group， rats in all other groups received daily intraperitoneal injections of D-galactose for six consecutive weeks. Subsequently， aggregated Aβ_25-35 was injected stereotactically into the bilateral ventricles to establish the AD model. During the intervention periods， the rats in all groups were administered their respective drugs and normal saline by gavage. The Morris water maze test was used to assess the capacity for spatial learning and memory. Hematoxylin-eosin （HE） staining was employed to observe the histopathological changes in the colon tissues. Immunofluorescence was used to detect Aβ_1-41 deposition in the hippocampal region and Mucin 2 （MUC2） expression in the colonic mucosa. Western blot was performed to measure the protein expression levels of FFAR2，TLR4， NF-κB p65， occludin （OCLN）， zonula occludens-1 （ZO-1）， and MUC2 in the colonic tissues. Enzyme-linked immunosorbent assay （ELISA） was used to determine the contents of interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， serum amyloid A （SAA）， and Aβ_1-42 in the hippocampal region from the colonic tissues. The lipopolysaccharide （LPS） concentrations in colon tissues of rats were measured by using a dynamic chromogenic limulus assay. ResultsCompared with those in the control group， the rats in the model group exhibited a significantly prolonged escape latency and a markedly shorter duration in the target quadrant （P<0.01）. The integrity of the colonic mucosal structure was compromised， with disordered gland arrangement and a reduced number of goblet cells. The Aβ_1-42 deposition in the hippocampal region was significantly increased （P<0.01）. The protein expression levels of TLR4 and NF-κB p65 in colonic tissues were significantly upregulated （P<0.01）， while those of occludin and ZO-1 were downregulated （P<0.01）. The contents of inflammatory factors such as IL-6， TNF-α， and SAA were significantly elevated （P<0.01）， and the LPS level in the serum was markedly increased （P<0.01）. In comparison to those in the model group， the rats in the Xixintang group showed a significantly shortened escape latency and a prolonged duration in the target quadrant （P<0.01）. The colonic mucosal structure was ameliorated， with neat gland arrangement and an increased number of goblet cells. The Aβ_1-42 deposition in the hippocampal region was reduced （P<0.01）. The protein expressions of TLR4 and NF-κB p65 in the colon tissues were decreased （P<0.05，P<0.01）， while the protein levels of occludin and ZO-1 were increased （P<0.01）. The contents of IL-6， TNF-α， and serum amyloid A （SAA） were decreased （P<0.01）， and the LPS level was reduced （P<0.01）. ConclusionXixintang can significantly ameliorate cognitive dysfunction of AD model rats， by means of restoring the colonic mucosal barrier structure， reducing cerebral Aβ deposition， and suppressing peripheral and central inflammatory response. Its mechanism of action may be closely associated with the suppression of the TLR4/NF-κB signaling pathway activation， reduction of endotoxin levels， and regulation of the gut-brain axis.

ObjectiveTo investigate the therapeutic mechanism of Danhe granules in treating mixed hyperlipidemia based on network pharmacology， as well as animal and cell experiments. MethodsThe active compounds and targets of Danhe granules were screened using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform （TCMSP） and the Encyclopedia of Traditional Chinese Medicine （ETCM）. Related targets for mixed hyperlipidemia were obtained from the GeneCards database. The intersecting targets were subjected to Gene Ontology （GO） functional annotation and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment analyses. A high-fat model was established in human hepatocellular carcinoma cells （HepG2） induced by palmitic acid （PA）， followed by intervention with Danhe granules to assess intracellular lipid accumulation and oxidative stress levels. A mixed hyperlipidemia rat model was also established and divided into low-， medium-， and high-dose Danhe granules groups （1.134， 2.268， and 4.536 g·kg^-1， respectively）， as well as a positive control group treated with pravastatin sodium （4.020 mg·kg^-1）. After eight weeks of intervention， serum lipid levels， inflammatory factors， oxidative stress indices， and the expression of key hepatic lipid metabolism-related proteins were determined. ResultsNetwork pharmacology identified 93 intersecting targets between Danhe granules and mixed hyperlipidemia， with peroxisome proliferator-activated receptor gamma （PPARG）， peroxisome proliferator-activated receptor alpha （PPARA）， tumor necrosis factor （TNF）， interleukin-6 （IL-6）， and IL-1B among the key nodes. The PPAR signaling pathway， AGE/RAGE signaling pathway， lipid metabolism， atherosclerosis and non-alcoholic fatty liver disease （NAFLD） were among the most significantly enriched pathways. Cellular experiments demonstrated that Danhe granules significantly reduced reactive oxygen species （ROS） and malondialdehyde （MDA） levels while increasing catalase （CAT） activity （P<0.05）， thereby alleviating intracellular lipid accumulation and triglyceride （TG） content in HepG2. In animal experiments， Danhe granules markedly decreased serum total cholesterol （TC）， TG， and low-density lipoprotein cholesterol （LDL-C） levels （P<0.05）， reduced hepatic MDA levels， and elevated superoxide dismutase （SOD） and CAT levels. Histological analysis showed alleviation of hepatic steatosis， upregulation of hepatic PPARA and lipoprotein lipase （LPL） expressions， and downregulation of sterol regulatory element-binding protein 1 （SREBP1） expression （P<0.05， P<0.01）. ConclusionDanhe granules improve lipid metabolism disorders in mixed hyperlipidemia by reducing MDA levels， enhancing SOD and CAT activities， scavenging excessive ROS， inhibiting oxidative stress， and mitigating liver injury. The underlying mechanism may involve the upregulation of PPARA and LPL and the suppression of SREBP1 expression.

ObjectiveThis study aims to investigate whether Xixintang could ameliorate cognitive dysfunction in an Alzheimer's disease （AD） rat model induced by D-galactose and β-amyloid （Aβ_25-35）， by means of repairing the colonic mucosal barrier， regulating the Toll-like receptor 4 （TLR4）/nuclear factor-κB p65 （NF-κB p65） signaling pathway， and intervening in the pathological process mediated by the gut-brain axis. MethodsSixty specific pathogen-free （SPF） male Sprague-Dawley （SD） rats were randomly divided to five groups （n=12）： A control group， a model group， a donepezil group， an Xixintang group， and a probiotic group. Except for those in the control group， rats in all other groups received daily intraperitoneal injections of D-galactose for six consecutive weeks. Subsequently， aggregated Aβ_25-35 was injected stereotactically into the bilateral ventricles to establish the AD model. During the intervention periods， the rats in all groups were administered their respective drugs and normal saline by gavage. The Morris water maze test was used to assess the capacity for spatial learning and memory. Hematoxylin-eosin （HE） staining was employed to observe the histopathological changes in the colon tissues. Immunofluorescence was used to detect Aβ_1-41 deposition in the hippocampal region and Mucin 2 （MUC2） expression in the colonic mucosa. Western blot was performed to measure the protein expression levels of FFAR2，TLR4， NF-κB p65， occludin （OCLN）， zonula occludens-1 （ZO-1）， and MUC2 in the colonic tissues. Enzyme-linked immunosorbent assay （ELISA） was used to determine the contents of interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， serum amyloid A （SAA）， and Aβ_1-42 in the hippocampal region from the colonic tissues. The lipopolysaccharide （LPS） concentrations in colon tissues of rats were measured by using a dynamic chromogenic limulus assay. ResultsCompared with those in the control group， the rats in the model group exhibited a significantly prolonged escape latency and a markedly shorter duration in the target quadrant （P<0.01）. The integrity of the colonic mucosal structure was compromised， with disordered gland arrangement and a reduced number of goblet cells. The Aβ_1-42 deposition in the hippocampal region was significantly increased （P<0.01）. The protein expression levels of TLR4 and NF-κB p65 in colonic tissues were significantly upregulated （P<0.01）， while those of occludin and ZO-1 were downregulated （P<0.01）. The contents of inflammatory factors such as IL-6， TNF-α， and SAA were significantly elevated （P<0.01）， and the LPS level in the serum was markedly increased （P<0.01）. In comparison to those in the model group， the rats in the Xixintang group showed a significantly shortened escape latency and a prolonged duration in the target quadrant （P<0.01）. The colonic mucosal structure was ameliorated， with neat gland arrangement and an increased number of goblet cells. The Aβ_1-42 deposition in the hippocampal region was reduced （P<0.01）. The protein expressions of TLR4 and NF-κB p65 in the colon tissues were decreased （P<0.05，P<0.01）， while the protein levels of occludin and ZO-1 were increased （P<0.01）. The contents of IL-6， TNF-α， and serum amyloid A （SAA） were decreased （P<0.01）， and the LPS level was reduced （P<0.01）. ConclusionXixintang can significantly ameliorate cognitive dysfunction of AD model rats， by means of restoring the colonic mucosal barrier structure， reducing cerebral Aβ deposition， and suppressing peripheral and central inflammatory response. Its mechanism of action may be closely associated with the suppression of the TLR4/NF-κB signaling pathway activation， reduction of endotoxin levels， and regulation of the gut-brain axis.

ObjectiveTo investigate the therapeutic mechanism of Danhe granules in treating mixed hyperlipidemia based on network pharmacology， as well as animal and cell experiments. MethodsThe active compounds and targets of Danhe granules were screened using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform （TCMSP） and the Encyclopedia of Traditional Chinese Medicine （ETCM）. Related targets for mixed hyperlipidemia were obtained from the GeneCards database. The intersecting targets were subjected to Gene Ontology （GO） functional annotation and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment analyses. A high-fat model was established in human hepatocellular carcinoma cells （HepG2） induced by palmitic acid （PA）， followed by intervention with Danhe granules to assess intracellular lipid accumulation and oxidative stress levels. A mixed hyperlipidemia rat model was also established and divided into low-， medium-， and high-dose Danhe granules groups （1.134， 2.268， and 4.536 g·kg^-1， respectively）， as well as a positive control group treated with pravastatin sodium （4.020 mg·kg^-1）. After eight weeks of intervention， serum lipid levels， inflammatory factors， oxidative stress indices， and the expression of key hepatic lipid metabolism-related proteins were determined. ResultsNetwork pharmacology identified 93 intersecting targets between Danhe granules and mixed hyperlipidemia， with peroxisome proliferator-activated receptor gamma （PPARG）， peroxisome proliferator-activated receptor alpha （PPARA）， tumor necrosis factor （TNF）， interleukin-6 （IL-6）， and IL-1B among the key nodes. The PPAR signaling pathway， AGE/RAGE signaling pathway， lipid metabolism， atherosclerosis and non-alcoholic fatty liver disease （NAFLD） were among the most significantly enriched pathways. Cellular experiments demonstrated that Danhe granules significantly reduced reactive oxygen species （ROS） and malondialdehyde （MDA） levels while increasing catalase （CAT） activity （P<0.05）， thereby alleviating intracellular lipid accumulation and triglyceride （TG） content in HepG2. In animal experiments， Danhe granules markedly decreased serum total cholesterol （TC）， TG， and low-density lipoprotein cholesterol （LDL-C） levels （P<0.05）， reduced hepatic MDA levels， and elevated superoxide dismutase （SOD） and CAT levels. Histological analysis showed alleviation of hepatic steatosis， upregulation of hepatic PPARA and lipoprotein lipase （LPL） expressions， and downregulation of sterol regulatory element-binding protein 1 （SREBP1） expression （P<0.05， P<0.01）. ConclusionDanhe granules improve lipid metabolism disorders in mixed hyperlipidemia by reducing MDA levels， enhancing SOD and CAT activities， scavenging excessive ROS， inhibiting oxidative stress， and mitigating liver injury. The underlying mechanism may involve the upregulation of PPARA and LPL and the suppression of SREBP1 expression.

ObjectiveTo investigate the effects of Huanglian Jiedutang （HLJDT） on cognitive function in mice with ischemic stroke （IS） and to elucidate whether its neuroprotective effects are mediated by inhibition of the nuclear factor-κB （NF-κB） signaling pathway and subsequent suppression of NF-κB-regulated neuronal apoptosis. MethodsAn IS model was established using middle cerebral artery occlusion （MCAO）. Sixty C57BL/6J mice were randomly assigned to five groups （n =12 per group）， i.e.， sham operation， model， HLJDT low-dose （3.9 g·kg^-1·d^-1）， HLJDT high-dose （7.8 g·kg^-1·d^-1）， and Ginkgo biloba extract （GBE， 31.2 mg·kg^-1·d^-1）. Post-operatively， neurological deficit scores （Longa score）， cerebral infarct volume assessed by 2，3，5-triphenyltetrazolium chloride （TTC） staining， and brain water content were evaluated. Learning and memory were assessed using new object recognition （NOR） and fear conditioning （FC） tests. Hippocampal pathology was examined via hematoxylin and eosin （HE） staining. Immunofluorescence detected expression of glial fibrillary acidic protein （GFAP， astrocyte marker）， cellular oncogene Fos （c-Fos， neuronal activation marker）， and glutamate decarboxylase 65 （GAD65）. Western blot measured nuclear factor-κB inhibitor protein α （IκBα）， phosphorylated IκBα （p-IκBα）， NF-κB p65， phosphorylated NF-κB p65 （p-NF-κB p65）， ionic calcium binding adapter molecule 1 （Iba-1）， tumor necrosis factor （TNF）-α， interleukin （IL）-1β， and apoptosis-related proteins， such as cleaved cysteinyl aspartate-specific protease 3 （Caspase-3）， B-cell lymphoma 2 （Bcl-2）， and Bcl-2-associated X protein （Bax）. Real-time quantitative PCR （Real-time PCR） was used to assess mRNA levels of Iba-1， TNF-α， IL-1β， NF-κB p65， cleaved Caspase-3， Bax， and Bcl-2. ResultsCompared with the sham group， the model group exhibited significantly increased neurological deficit scores， brain water content， and cerebral infarct volume （P<0.01）. Hippocampal CA1 neurons were disorganized， showing nuclear pyknosis and karyolysis. NOR exploration time and FC freezing time were significantly reduced （P<0.01）. GFAP and c-Fos expression were increased， while GAD65 expression was decreased （P<0.01）. Cleaved Caspase-3 and Bax were upregulated， Bcl-2 was downregulated， and the Bax/Bcl-2 ratio was elevated （P<0.01）. Expression levels of p-IκBα， p-NF-κB p65， IL-1β， TNF-α， and Iba-1 were significantly increased （P<0.01）. Compared with the model group， HLJDT high-dose， low-dose， and GBE groups showed significant improvements in all parameters （P<0.01）. Among them， the HLJDT high-dose group showed the most pronounced neuronal structural recovery and superior performance in NOR and FC tests （P<0.01）. In this group， GFAP and c-Fos decreased， GAD65 increased （P<0.01）， apoptosis-related protein expression was reversed， and NF-κB signaling and related inflammatory factor expression were suppressed （P<0.01）. ConclusionHLJDT ameliorates cognitive dysfunction in mice after IS， potentially by inhibiting the NF-κB signaling pathway， thereby reducing neuroinflammation and hippocampal neuronal apoptosis.

BACKGROUND:Rapid and accurate segmentation of brain tissue in medical images is of great significance for three-dimensional biomechanical modeling and diagnosis of craniocerebral injuries.Currently,artificial intelligence(AI)-based baseline models exhibit excellent generalization capabilities on large-scale datasets.However,due to the specificity and complexity of craniocerebral tissues,these models have certain limitations in their application to craniocerebral tissue segmentation.Additionally,the scarcity of craniocerebral tissue samples makes it difficult for baseline models to achieve precise segmentation results through fine-tuning.OBJECTIVE:To construct a craniocerebral tissue segmentation model based on texture feature retrieval enhancement to improve segmentation accuracy under a small number of samples.METHODS:Segment Anything in Medical Images(MedSAM)model was selected as the basic framework,and texture features were combined with deep learning to build a brain tissue segmentation model based on texture feature retrieval enhancement(DP-MedSAM).Dice Coefficient and mean intersection over union(MIoU)were selected to evaluate the efficiency of image segmentation results.In comparison with the original MedSAM model,the ablation experiment systematically evaluated the influence of key components on the model performance.The sensitivities of MedSAM,the Segment Anything Model(SAM)for medical image segmentation(SAM-Med2D)and DP-MedSAM in the mandible,left optic nerve,and left parotid gland were compared.RESULTS AND CONCLUSION:(1)By verifying the impact of the number of point prompts on segmentation results on the HaN-Seg dataset,the experimental results indicated that the optimal Dice score was achieved with the addition of three points.(2)DP-MedSAM demonstrated performance improvements compared with MedSAM and SAM-Med2D on two datasets(HaN and Public Domain Database for Computational Anatomy).Especially on the Public Domain Database for Computational Anatomy dataset,in terms of the MIoU metric,DP-MedSAM outperformed MedSAM by 6.59％and SAM-Med2D by 37.35％;in terms of the Dice metric,DP-MedSAM outperformed MedSAM and SAM-Med2D by 4.34％and 25.32％,respectively.(3)The ablation experiment results showed that removing the texture feature extraction module in the DP-MedSAM model,relying solely on original image features,led to a significant decrease in results on the test set.Furthermore,removing the vector cache database and its retrieval enhancement function from the model,which deprived the ability of the model to perform similarity retrieval using an external knowledge base,further reduced model performance.(4)Under conditions of limited data resources,the DP-MedSAM model outperformed the other two models in all evaluation metrics.The DP-MedSAM model performed excellently when processing simple and moderately difficult samples,demonstrating a clear advantage over the other two models and indicating good generalization ability.Processing the fine structures of difficult samples placed higher demands on the model's segmentation capabilities.Although the performance of the DP-MedSAM model declined slightly,it still outperformed the other two models.(5)This study proposes an innovative craniocerebral tissue segmentation model,DP-MedSAM,which improves the baseline model's performance in capturing local details and global structural information in medical images by introducing target region texture feature extraction.Through vector similarity retrieval technology,DP-MedSAM can retrieve the feature vector most similar to the current target region from a pre-constructed vector database,providing more precise guiding information for the segmentation process.

BACKGROUND:In vitro construction of tissue-engineered intestinal models plays an important role in intestinal regeneration and intestinal disease research.The interaction of intestinal nervous system and intestinal epithelial barrier to maintain body homeostasis is a hot topic in the bionic construction of tissue-engineered intestinal tract.OBJECTIVE:To construct a bionic model that can mimic the enteric nervous system in vivo.METHODS:Using fibroin protein with villus structure as scaffold,human induced neural stem cells solidified with collagen were added to intestinal epithelial cells(Caco-2 and HT29-MTX-E12)for 3-day culture to construct a co-culture system of intestinal epithelial cells and nerve cells(co-culture group).Human induced neural stem cells or intestinal epithelial cells cultured alone that were inoculated with fibroin scaffolds were set as controls.Cell morphology was observed by scanning electron microscopy and hematoxylin-eosin staining.Cell activity was detected by Live/Dead cell staining.Human induced neural stem cell differentiation was detected by β-microtubulin immunofluorescence staining.Intestinal epithelial histological properties and barrier function were detected by microvillin,sucrase-isomaltase,tight junction protein 1,E-calmodulin,and mucin-2 immunofluorescence staining.The function of mucus secretion from intestinal epithelial cells was detected by Alcian blue staining.Alkaline phosphatase staining was performed to detect differentiation of intestinal epithelial cells,at the same time,sucrase-isomaltase,tight junction protein 1,and alkaline phosphatase mRNAs were detected by RT-qRCR.RESULTS AND CONCLUSION:The neuralized intestinal mucosal co-culture model with villi structure was successfully constructed,and neural stem cells and intestinal epithelial cells on the fibroin scaffold showed good cellular activities.After neuralization,the activity of alkaline phosphatase and sucrase-isomaltase in intestinal epithelial cells was enhanced,while the expression level of tight junction protein 1 was up-regulated.To conclude,the neuralized bionic intestinal epithelial model is beneficial to the maturation of intestinal mucosal epithelial cells and the formation of barrier function.

BACKGROUND:Triptolide,a bioactive component of the traditional Chinese medicine Tripterygium wilfordii,has a certain protective effect on neurons.OBJECTIVE:To investigate the effect of triptolide on cerebral ischemia/reperfusion injury.METHODS:(1)Cell experiment:Hippocampal neurons(HT22 cells)were randomly divided into control group,glucose oxygen deprivation/reoxygenation(OGD/R)group,OGD/R+triptolide group,OGD/R+triptolide+si-TIGAR group,OGD/R+si-TIGAR group,and OGD/R+triptolide+rapamycin group.HT22 cell viability was detected by cell counting kit 8.Tp53-induced glycolysis and apoptosis factors,glutathione peroxidase 4,7 members of the solsolic vector family 11,sphingosine kinase 1(SPHK1)and(mTOR)were detected by western blot assay.Glutathione,malondialdehyde and iron level were detected using the biochemical kit.(2)Animal experiment:Rats were randomly divided into sham surgery group,model group,and triptolide group.Cerebral artery occlusion/reperfusion rat models were prepared in the latter two groups.Rats in the triptolide group were orally administered 50 mg/kg triptolide for 7 days.Twenty-four hours after administration,LONGA method was used to evaluate the neurological impairment of rats,TTC method was used to observe the conditions of cerebral infarction,TUNEL staining was used to detect cell apoptosis,and western blot was performed to detect the expression level of related proteins.RESULTS AND CONCLUSION:(1)At the cellular level,triptolide promoted cell viability and inhibited apoptosis in HT22 cells treated with OGD/R.Triptolide also increased the expression levels of Tp53-induced glycolysis and apoptosis factors,glutathione peroxidase 4,and 7 members of the solsolic vector family 11,activated the SPHK1/mTOR pathway,increased glutathione content,inhibited malondialdehyde content and iron levels.Rapamycin treatment counteracted the protective effect of triptolide on HT22 cells.(2)At the animal level,triptolide significantly reduced neurological deficits,infarct volume,and cell apoptosis,and inhibited neuronal ferroptosis in brain tissue of rats.To conclude,triptolide can inhibit ferroptosis by upregulating the expression level of Tp53-induced glycolysis and apoptosis factors and activating the SPHK1/mTOR signaling,and thereby reduced cerebral ischemia/reperfusion injury.These findings suggest that triptolide may be a candidate drug for the treatment of cerebral ischemia/reperfusion injury.

BACKGROUND:As a mainstream surgical technique for the treatment of cervical spondylotic myelopathy through the anterior cervical subtotal decompression and bone graft fusion,it has many advantages.However,due to the high risk of this surgery and the particularity of the cervical anatomy,it is also a challenge for the surgeon.The gradual maturity of 3D printing technology and the continuous development of applications in the medical field are now able to provide more perfect personalized treatment.OBJECTIVE:To investigate the efficacy of 3D printed titanium cage cutting model in anterior cervical vertebrae subtotal decompression and bone graft fusion.METHODS:Medical records of 57 patients undergoing anterior cervical corpectomy decompression and fusion surgery admitted to the Department of Spine Surgery of Affiliated Hospital of Yan'an University from April 2021 to April 2023 were retrospectively analyzed.According to whether the 3D printed titanium cage cutting model was used in the operation,the patients were divided into the traditional titanium cage bone grafting group(control group,n=30)and the 3D printed titanium cage model group(observation group,n=27).The general data,amount of blood loss during operation,number ofC-arm X-ray machine fluoroscopy during operation,operation time,as well as anterior intervertebral edge height(H1),posterior intervertebral edge height(H2)and C2-C7 Cobb angle of the two groups measured on the cervical lateral X-ray films before,3 days and 6 months after operation were recorded and analyzed.The settling degree of the titanium cage was assessed with the distance of the height of the anterior and posterior edges of the vertebral body at 3 days and 6 months after surgery.Visual analog scale was used to evaluate neck pain and Japanese Orthopaedic Association was used to evaluate nerve function.RESULTS AND CONCLUSION:(1)Follow-up was conducted for at least 6 months.(2)The amount of intraoperative blood loss and fluoroscopy times in the observation group were less than those in the control group(P＜0.05).The operative time of the observation group was significantly shorter than that of the control group(P＜0.05).(3)There were no significant differences in C2-C7 Cobb angle,visual analog scale score,Japanese Orthopaedic Association score,anterior vertebral border height(H1)and posterior vertebral border height(H2)before surgery,3 days and 6 months after surgery between the two groups(P＞0.05).(4)There were five patients in the observation group(with severe subsidence rate of 19％)with severe subsidence at the anterior and posterior edges of the surgical segment,and seven patients in the control group(with severe subsidence rate of 23％)with severe subsidence(H1 or H2 subsidence≥3 mm)at the surgical segment 6 months after surgery.There was no significant difference in the rate of severe subsidence of titanium cage between the two groups(P＞0.05).(5)At the last follow-up,bone fusion was achieved at the operative level in both groups,and there was no statistical significance in bone graft fusion rate between the two groups(P＞0.05).(6)The results showed that the application of 3D printed titanium cage cutting model in anterior cervical corpectomy decompression and fusion surgery had the same clinical effect as that of traditional surgery,but the former could effectively reduce the fluoroscopy times of C-arm X-ray machine,the amount of blood loss and the operation time,and had unique advantages in the pruning and implantation of titanium cage during surgery.

BACKGROUND:The local immune microenvironment plays an important regulatory role in the process of bone formation,and the immune system is intricately linked to the skeletal system.OBJECTIVE:To systematically review the promotion of bone regeneration from three aspects:immune cell regulation of microenvironment,regulation of immune response by small extracellular vesicles,and induction of immune response by bone biomaterials,and to elucidate the immune regulatory mechanisms involved in bone regeneration.METHODS:Relevant literature was retrieved from PubMed,CNKI,WanFang Database,and VIP Database,using the search terms of"osteoimmunology,immune microenvironment,small extracellular vesicles,bone regeneration,bone tissue repair,biomaterials,and tissue engineering"in English and Chinese.Repeat and irrelevant literature was screened and removed,and 92 articles that met the criteria were selected for intensive reading and review.RESULTS AND CONCLUSION:Multiple immune cells and bone cells are in the same microenvironment,and immune cells can regulate the differentiation and activity of bone cells,collectively forming an immune microenvironment that affects bone regeneration.Neutrophils can significantly reduce local inflammatory responses in the early stages of bone injury,creating a favorable microenvironment for bone regeneration.M1 macrophages can clear foreign bodies and reduce early inflammatory responses,while M2 macrophages can promote the expression of osteogenic markers and factors,playing an important role in the repair process of bone injury.B cells and T cells can directly or indirectly affect the generation and activity of osteoblasts and osteoclasts,regulate bone metabolism,and promote bone regeneration.Extracellular vesicles of small cells regulate the local immune microenvironment through paracrine secretion,promoting bone formation and angiogenesis at the site of bone injury.The metal ions,surface hydrophilicity,porosity,pore size,surface morphology,and surface roughness on the surface of biomaterials can directly regulate local immune responses,and have anti-inflammatory,angiogenic,and osteogenic effects,thereby accelerating bone regeneration.