BACKGROUND:Magnetic nanomaterials,as a hot topic in the biomedical field in recent years,are often used to enhance the targeted delivery of drugs to the affected area.OBJECTIVE:To investigate the effects of magnetic nano drug carriers on skeletal muscle injury markers and inflammatory responses in rats with sports injuries.METHODS:Magnetic nanoparticles were prepared.A total of 88 male SD rats were randomly divided into a blank group(n=8),an injury control group(n=32),a Yunnan Baiyao group(n=24),and a magnetic nano-drug carrier group(n=24)by using a random number table method.The latter three groups were modeled with exercise-induced muscle injury(treadmill slope of-16°,running speed of 16 m/min,and training time of 120 min).Immediately after exercise,after verifying the success of the model,Yunnan Baiyao patch was applied to the gastrocnemius muscle of the rats in the Yunnan Baiyao group.Yunnan Baiyao patch loaded with magnetic nanoparticles was applied to the gastrocnemius muscle of the rats in the magnetic nano-drug carrier group.At 24,48,and 120 hours after exercise,blood was drawn from the abdominal aorta of rats to detect the activities of creatine kinase and lactate dehydrogenase,as well as the levels of myoglobin,interleukin-6,and tumor necrosis factor-α.Hematoxylin-eosin staining was used to observe the infiltration of inflammatory cells in the gastrocnemius muscle.RESULTS AND CONCLUSION:(1)Compared with the blank group,the levels of myoglobin,creatine kinase,lactate dehydrogenase and tumor necrosis factorα in the injury control group at 24,48 and 120 hours after exercise were increased(P＜0.05),and the level of interleukin 6 at 24 and 120 hours after exercise was increased(P＜0.05).Compared with the injury control group,the level of myoglobin in the Yunnan Baiyao group at 24 and 48 hours after exercise was decreased(P＜0.05),the activities of creatine kinase and lactate dehydrogenase at 24,48 and 120 hours were decreased(P＜0.05),and the levels of interleukin 6 and tumor necrosis factor α at 120 hours after exercise were decreased(P＜0.05).Compared with the Yunnan Baiyao group,the level of myoglobin in the magnetic nano-drug carrier group at 24 and 48 hours after exercise was decreased(P＜0.05),the activities of creatine kinase and tumor necrosis factor α at 48 and 120 hours after exercise were decreased(P＜0.05),and the lactate dehydrogenase activity was reduced(P＜0.05).(2)Hematoxylin-eosin staining showed that a large number of inflammatory cells infiltrated in the muscle fibers of the injury control group 24 hours after exercise,and then the inflammatory cell infiltration gradually decreased,and the local damaged muscle fibers began to regenerate 120 hours after exercise.A large number of inflammatory cells infiltrated in the muscle fibers of the Yunnan Baiyao group and the magnetic nano-drug carrier group 24 hours after exercise,and then the inflammatory cell infiltration gradually decreased,and the damaged muscle fibers were regenerating 120 hours after exercise,and there was no significant difference from the blank group.(3)The results show that Yunnan Baiyao patch combined with magnetic nanoparticles can accelerate the recovery of exercise-induced muscle injury in rats,and the effect is better than that of Yunnan Baiyao alone.

BACKGROUND:Currently,there are many modeling methods for pelvic organ prolapse animal models,and the commonly used methods are vaginal balloon dilatation,oophorectomy and the combination of the two.There is no study comparing the three modeling methods in detail.OBJECTIVE:To construct and validate a rat animal model of pelvic organ prolapse using three different methods and to identify the advantages and disadvantages of various models.METHODS:Seventy-two 8-week SPF-grade female Sprague-Dawley rats were selected and randomly divided into four groups,namely,vaginal balloon dilatation group,ovariectomy group,ovariectomy combined with vaginal balloon dilatation group(the combined group),and the sham-operated group(no ovariectomy and no vaginal dilatation).The vaginal wall tissues of rats were collected at 4,8 and 12 weeks after the operation for hematoxylin-eosin staining,Masson staining,EVG staining and immunohistochemical staining of α-smooth muscle actin,Vimentin and matrix metalloproteinase 9 detection,and the pelvic floor muscle tissues were taken at 4,8 and 12 weeks after the operation for hematoxylin-eosin staining,Masson staining and EVG staining.RESULTS AND CONCLUSION:(1)Hematoxylin-eosi staining showed that there was no significant difference in the decrease of vaginal epithelial layer thickness in the vaginal balloon dilatation group compared with the sham-operated group,(P＞0.05),while the thickness of the vaginal epithelial layer was significantly reduced in the ovariectomy group and the ovariectomy combined with vaginal balloon dilation group(P＜0.001),and the reduction was more significant in the ovariectomy combined with vaginal balloon dilation group,remained stable at 8 weeks after surgery and lasted until 12 weeks.(2)The changes in the content of collagen fibers and elastic fibers in the vaginal wall stained by Masson and EVG staining were the same as the changes in the thickness of the vaginal epithelial layer stained by hematoxylin-eosin,and there were no changes in collagen fibers and elastic fibers in the pelvic floor muscle tissues of the treatment groups.(3)At 4,8 and 12 weeks after treatment,there was no significant difference in the expression levels of α-smooth muscle actin,Vimentin and matrix metalloproteinase 9 in the vaginal wall tissue of the balloon dilation group compared with the control group(P＞0.05),whereas the expression levels of α-smooth muscle actin and Vimentin were significantly decreased in the ovariectomy group and ovariectomy combined with vaginal balloon dilation group(P＜0.01)and the expression of matrix metalloproteinase 9 showed a significant increase(P＜0.01),with a more pronounced increase in the ovariectomy combined with vaginal balloon dilation group,and the increase reached a stable state at 8 weeks after surgery and could persist up to 12 weeks.To conclude,vaginal balloon dilatation could not maintain the degeneration of pelvic organ prolapse formed by the vaginal wall for a long period,and both ovariectomy and the combined method can be used.Ovariectomy combined with vaginal balloon dilatation can significantly accelerate and aggravate the formation of typical histological features of pelvic organ prolapse in vaginal wall tissues,effectively shorten the experimental period,and improve the efficiency.These effects reach a stable state at 8 weeks after surgery and can be sustained up to 12 weeks,which is practical and convenient for the study of pelvic organ prolapse animal models.

BACKGROUND:Maxillofacial bone three-dimensional(3D)printing technology has been widely used in clinical diagnosis and treatment,but the data source before performing maxillofacial bone 3D printing mainly comes from the CT scanning data.The lens,thyroid and other parts of the human body are extremely sensitive to X-rays;therefore,it is particularly important to effectively reduce the dose of CT radiation when acquiring the data source.OBJECTIVE:To explore the feasibility of low-dose CT technology in optimizing radiation dose for maxillofacial bone 3D printing.METHODS:The medical records of 65 patients who underwent maxillofacial bone 3D printing in the Department of Stomatology at the General Hospital of Northern Theater Command from March 2021 to December 2023 were retrospectively collected and categorized into a conventional CT-dose 3D printing group(conventional CT-dose,120 kVp,automated tube current modulation,n=32)and a low-CT-dose 3D printing group(low-CT-dose group,80 kVp,automated tube current modulation,n=33).The effective dose of radiation was calculated and compared between the two groups.A Likert scale was used to evaluate the quality of 3D printing in the two groups,and the measurement bias and consistency between evaluators were measured using the Bland-Altman method.RESULTS AND CONCLUSION:(1)There was no significant difference in the general demographic characteristics(age,height,weight,body mass,sex,and body mass index)between the two groups(all P＞0.05).(2)The effective dose value of the low CT-dose 3D printing group was(0.3±0.1)mSv,which was about 62.5％lower than that in the conventional CT-dose 3D printing group[(0.8±0.1)mSv].(3)There was no significant difference in the subjective scoring of 3D printing quality between the two groups(all P＞0.05).The subjective consistency among evaluators was good,with Kappa values of 0.85,0.80,and 0.76.The scatter points in the Bland-Altman for both protocols were uniformly distributed within the standard deviation line,indicating good consistency between the two groups.To conclude,low-dose CT technology can be effectively applied in maxillofacial bone 3D printing,reducing radiation dose without affecting the quality of 3D printing.

BACKGROUND:Type 2 diabetes mellitus is a secondary causative factor for osteoporosis.As highly heterogeneous innate immune cells,macrophages may be polarized in a hyperglycemic environment,which affects osteogenesis-angiogenesis coupling.This may be a research target for improving bone quality in patients with type 2 diabetic osteoporosis.OBJECTIVE:To explore the role of modulating macrophage M1/M2 polarization to influence osteogenesis-angiogenesis coupling in type 2 diabetic osteoporosis and to summarize the effects of commonly used anti-glucose and anti-osteoporosis drugs and bone biorepair materials on bone osteogenesis-angiogenesis coupling by regulating macrophage M1/M2 polarization.METHODS:The keywords of"macrophage polarization,type 2 diabetes,osteoporosis,osteogenesis-angiogenesis coupling"in Chinese and"macrophages,macrophage polarization,osteogenesis-angiogenesis coupling"in English were used to search for relevant literature in CNKI and PubMed,respectively.Seventy-nine pieces of literature were screened and analyzed.RESULTS AND CONCLUSION:(1)Type 2 diabetes mellitus causes the body to be in a hyperglycemic environment and increases the secretion of inflammatory-related factors in the body,which promotes macrophage polarization towards M1 and decreases the number of M2 macrophages.(2)In type 2 diabetes,promoting M2 macrophage polarization is beneficial for osteogenesis-angiogenesis coupling.(3)Some anti-glycemic drugs,active ingredients in traditional Chinese medicine and bone biorepair materials can improve type 2 diabetic osteoporosis by regulating macrophage M1/M2 polarization,reducing M1/M2 ratio,and promoting osteogenesis-angiogenesis coupling.

BACKGROUND:The exact pathogenesis of temporomandibular joint osteoarthritis is currently unclear.Traditional clinical treatment strategies for temporomandibular joint osteoarthritis are symptomatic treatments such as pain relief and reduction of inflammation,which can stop the progression of the disease to a certain degree but cannot reverse the destruction of the cartilage.Cartilage degeneration,as one of the most prominent pathologic features in the development of temporomandibular joint osteoarthritis,has been the subject of an increasing number of studies that focus on its pathogenesis.Consequently,we hope to provide an ideal radical solution for the regeneration of the temporomandibular joint.OBJECTIVE:To review the progress of research on cartilage degeneration in temporomandibular joint osteoarthritis.METHODS:The search terms were"temporomandibular joint osteoarthritis,degradation of cartilage matrix,synovitis,oxidative stress,chondrocyte hypertrophy,chondrocyte apoptosis,ferroptosis,autophagy,angiogenesis,extracellular vesicles"in Chinese and English.Literature search was conducted in PubMed database and CNKI,and the time limit for the search was from January 2004 to October 2024.Screening was performed by analyzing and reading the literature,and according to the inclusion and exclusion criteria,81 papers were finally included for review.RESULTS AND CONCLUSION:(1)Increased secretion of cartilage matrix degrading enzymes causes degradation of the cartilage matrix,leading to cartilage degeneration.(2)Synovitis promotes cartilage degeneration through macrophage M1-type polarization and production of inflammatory mediators.(3)Oxidative stress promotes cartilage degeneration by exacerbating the inflammatory response through overproduction of reactive oxygen species.(4)Chondrocyte phenotypic changes and death lead to the decrease of cartilage matrix synthesis,resulting in cartilage degeneration.(5)Blood vessels of subchondral bone penetrate the calcified cartilage layer to reach the superficial cartilage layer,which destroys the cartilage structure and leads to cartilage degeneration.(6)Bioactive substances carried by serum-derived extracellular vesicles in inflammatory states also promote cartilage degeneration in temporomandibular joint osteoarthritis.

BACKGROUND:3D-printed bone tissue engineering scaffolds have obvious advantages in the research and clinical treatment of bone defect repair.As one of the important raw materials for 3D printed bone scaffolds,poly-L-lactic acid has a great potential for application in performing bone defect repair,but clinical patients with different bone defect causative factors have different requirements for the comprehensive performance of poly-L-lactic acid bone scaffolds.OBJECTIVE:To summarize and review the development of 3D printing technology and poly-L-lactic acid scaffolds and the design strategies chosen for scaffolds for bone repair in the setting of bone diseases such as osteomyelitis,bone tumor,osteonecrosis,and osteoporosis.METHODS:Literature from CNKI,WanFang,PubMed,Science Direct,and Web of Science databases were searched and screened from 1994 to 2024.Search terms were"3D printing,polylactic acid,bone tissue engineering scaffold,osteomyelitis,bone tumor,osteonecrosis,osteoporosis,bone defect"in Chinese and English.The screened 62 articles were systematically summarized and analyzed.RESULTS AND CONCLUSION:(1)Poly-L-lactic acid is considered to be an ideal raw material for artificial bone scaffold design due to its non-toxicity,processability,biocompatibility,and ability to self-degrade in the human environment.The application of 3D printing technology has enabled poly-L-lactic acid bone scaffolds to meet the multilayered and porous structural design requirements of biomimetic artificial bone repair materials,and to optimize the mechanical properties for better bone repair.(2)According to different bone disease microenvironments,timely adjustment of the functional design of poly-L-lactic acid scaffolds is important for the comprehensive osteogenic efficacy of the scaffolds.The article discusses the application of poly-L-lactic acid scaffolds in bone disease environments such as osteomyelitis,bone tumor,osteonecrosis,and osteoporosis,and highlights the importance of rationally grasping the timing of bone disease treatment and bone tissue regeneration for bone defects caused by different bone diseases.(3)Although poly-L-lactic acid scaffolds show potential in bone repair,there are still some problems,such as the need to further optimize the structural design of the scaffolds to fit new bone regeneration,enhance the bioactivity of the scaffolds,and take into account other functions(e.g.,antimicrobial,anti-tumor,and anti-osteoporosis)in order to adapt to the needs of bone tissue repair in different pathological environments.

BACKGROUND:Spondylolisthesis is a common disease,and there is a lack of effective drugs to treat it.There is still a need to further define the pathogenesis and screen out more suitable therapeutic targets for spondylolisthesis.Mendelian randomization analysis can be used to explore the drugable genes associated with spondylolisthesis and provide valuable guidance for the development of more effective and targeted therapeutic drugs.OBJECTIVE:To explore potential therapeutic targets and effective drugs for spondylolisthesis by means of pharmaceutically available genome-wide Mendelian randomization analysis.METHODS:Using the Finnish database,eQTLGen consortium,drug signature database,drug-gene interaction database,protein-protein interaction database,organic small molecule biological activity database and protein structure database,which contains genome and health information of half a million Finns,data on druggable genes were subjected to two-sample Mendelian randomization analysis and co-localization analysis with data from genome-wide association studies of spondylolisthesis to identify genes highly associated with spondylolisthesis.In addition,GO and KEGG enrichment analysis,protein network construction,drug prediction and molecular docking were performed to provide valuable guidance for the development of more effective and targeted therapeutic agents.RESULTS AND CONCLUSION:In this study,we identified 34 potential drug target genes that were significantly associated with spondylolisthesis,particularly the gene APOBEC3G.This gene showed a significant association with spondylolisthesis outcomes through Mendelian analysis and co-localization analysis,suggesting that APOBEC3G may be a priority therapeutic target.As for other potential mechanisms and drugs,we still need to conduct more in-depth research to determine their roles.This study used a database from a European population,which can be used as a reference for the study of population genetics in China.

BACKGROUND:Macrophages play a key role in the occurrence and progression of lung diseases,and autophagy plays an important role in maintaining environmental homeostasis and functional stability in macrophages.It has been suggested that macrophage autophagic activity has two sides in lung inflammatory diseases.OBJECTIVE:To summarize the relationship between macrophage autophagy and lung diseases,thereby providing reference for exploring the prevention and treatment strategies of lung inflammatory diseases by targeting macrophage autophagy.METHODS:Literature retrieval was performed in CNKI and PubMed for relevant literature published from database inception to September 2024.The search terms were"macrophage autophagy,efferocytosis,macrophage polarization,acute lung injury,pneumonia,chronic obstructive pulmonary disease,pulmonary fibrosis,asthma"in Chinese and English,respectively.The search results were included or excluded based on the selection criteria,and 100 papers that met the criteria were finally included in the review.RESULTS AND CONCLUSION:(1)The obstruction of autophagy flow will induce the polarization imbalance of macrophages and impair their efferocytosis,resulting in the increase of M1 macrophages and aggravating inflammation.(2)The judgment of autophagic activity should be based on whether the autophagy flow is smooth or not,and it is essential to evaluate the degradation ability of autophagy.Some studies failed to comprehensively detect the degradation ability of autophagy lysosomes to assess whether the autophagy flow is unobtrusive.As a result,the so-called two-sided view of pulmonary macrophage autophagy in pulmonary inflammatory diseases in such studies is actually related to the one-sided judgment of autophagy activity.(3)The pathological manifestations vary across different pulmonary diseases and even at different stages of the same disease.Activation of macrophage autophagy plays a positive role in regulating pulmonary inflammatory homeostasis in conditions such as acute lung injury,infectious pneumonia,mild chronic obstructive pulmonary disease,early-stage pulmonary fibrosis,and secondary asthma.However,in the severe fibrotic stage of chronic obstructive pulmonary disease and the progressive stage of pulmonary fibrosis,the activation of pulmonary macrophage autophagy aggravates pulmonary fibrosis,reflecting the dual nature of macrophage autophagy.In allergic asthma,autophagy is activated in lung-resident macrophages but suppressed in infiltrating monocyte-derived macrophages from circulation.The former is closely related to airway stenosis,and the latter aggravates pneumonia disorders.Therefore,identifying the types and progression stages of lung diseases,along with accurately assessing autophagic activity,is crucial for future investigations into the relationship between macrophage autophagy and disease pathogenesis,thereby facilitating the development of therapeutic strategies in the future.

BACKGROUND:In 2019,the modified cortical bone trajectory technique was proposed by our team,significantly improving traditional methods.Previous studies have highlighted its superior biomechanical properties for segment fixation.However,a comprehensive systematic analysis of its specific biomechanical effects on adjacent segment degeneration is lacking,particularly regarding its influence on range of motion and intervertebral disc stress in posterior lumbar interbody fusion and transforaminal lumbar interbody fusion techniques.OBJECTIVE:To investigate the biomechanical effects of modified cortical bone trajectory screw techniques on adjacent segment degeneration in posterior lumbar interbody fusion and transforaminal lumbar interbody fusion.METHODS:CT scans were performed on three human cadaver specimens to establish and validate three-dimensional intact finite element models of the L1-S1 segment.For each of these,the posterior lumbar interbody fusion or transforaminal lumbar interbody fusion with three different fixation techniques was reconstructed at the L4-L5 segment.The L4-L5 segment was fixed using three different internal fixation techniques(modified cortical bone trajectory,cortical bone trajectory,and traditional pedicle screws).The range of motion and von Mises stress of the intervertebral disc of the L3-L4 and L5-S1 segments were recorded with a 400 N compressive load and 7.5 N moments in flexion,extension,left-right bending,and left-right rotation.The impacts of the three internal fixation techniques on adjacent segment degeneration in the two kinds of fusion were compared and analyzed.RESULTS AND CONCLUSION:(1)In the posterior lumbar interbody fusion model,the modified cortical bone trajectory screw group showed a reduced range of motion on adjacent segments(L3-L4,L5-S1)under six loading conditions compared to both the cortical bone trajectory screw group and traditional bone trajectory screw group.Specifically,the modified cortical bone trajectory screw group significantly reduced the maximum stress on the intervertebral disc in the superior adjacent segment(L3-L4)during extension compared to the traditional bone trajectory screw group(P=0.005),while the stress on the intervertebral disc in the inferior adjacent segment(L5-S1)exhibited greater dispersion.Similarly,the cortical bone trajectory screw group also significantly reduced the maximum stress on the intervertebral disc in the superior adjacent segment(L3-L4)during extension compared with the traditional bone trajectory screw group(P=0.03).(2)Compared with transforaminal lumbar interbody fusion,the three internal fixation techniques(modified cortical bone trajectory,cortical bone trajectory,and traditional pedicle screws)showed a trend of reduced range of motion in the inferior adjacent segment(L5-S1)under six loading conditions.In contrast,the maximum stress on the intervertebral discs in both the superior and inferior adjacent segments(L3-L4,L5-S1)exhibited an increasing trend in the posterior lumbar interbody fusion model.(3)It is concluded that in the posterior lumbar interbody fusion model,the modified cortical bone trajectory screw exhibited superior biomechanical properties in reducing the range of motion at adjacent segments,which may have a beneficial effect on reducing the risk of adjacent segment degeneration.

BACKGROUND:Studies have shown that there is a close relationship between pyroptosis,inflammatory factors and osteoporosis.OBJECTIVE:To review the effects of pyroptosis and inflammatory factors on the pathogenesis of osteoporosis from the perspectives of osteogenic differentiation and osteoclastic differentiation,based on an overview of pyroptosis in relation to the interaction of relevant inflammatory factors.METHODS:The first author used the computer to search the literature published by each database until 2024,and searched CNKI,WanFang,VIP and PubMed databases with the search terms of"pyroptosis,inflammatory factors,osteoporosis,osteoblast,osteoclast,bone metabolism,signaling pathway,review"in Chinese and English.A total of 79 papers were finally included according to the inclusion criteria.RESULTS AND CONCLUSION:The progression of osteoporosis is closely related to inflammation,in which pyroptosis plays a key role.Immune cells induce pyroptosis through apoptosis pathway,promote the secretion of inflammatory factors such as interleukin-18,interleukin-1β and NLRP3,build an inflammatory immune microenvironment,and regulate bone metabolism through complex signaling pathways,resulting in enhanced bone absorption and reduced bone formation,thereby leading to osteoporosis.Previous studies have shown that inhibiting pyroptosis is anti-inflammatory and slows the progression of osteoporosis,and it has been shown to improve inflammatory bone loss in vitro and in animal models.At present,research on pyroptosis and osteoporosis is limited.On the one hand,the exact mechanism of osteoporosis and the pathogenesis of pyroptosis are unknown,and the specific pathways and regulatory mechanisms remain to be understood.On the other hand,therapeutic strategies targeting pyroptosis are still theoretical,not clinically proven,and drug side effects are unknown.In the future,the research focus is to further explore the pathogenesis,especially the mechanism of pyroptosis,identify potential therapeutic targets,further study the pyroptosis signaling pathway and Gasdermin protein,and develop new drugs to improve the therapeutic effect in patients with osteoporosis.