Micro-grinding has been widely used in aerospace and other industry.However,the small diameter of the micro-grinding tool has limited its machining performance and efficiency.In order to solve the above problems,micro...Micro-grinding has been widely used in aerospace and other industry.However,the small diameter of the micro-grinding tool has limited its machining performance and efficiency.In order to solve the above problems,micro-structure has been applied on the micro-grinding tool.A morphology modeling has been established in this study to characterize the surface of microstructured micro-grinding tool,and the grinding performance of micro-structured micro-grinding tool has been analyzed through undeformed chip thickness,abrasive edge width,and effective distance between abrasives.Then deviation analysis,path optimization and parameter optimization of microchannel array precision grinding have been finished to improve processing quality and efficiency,and the deflection angle has the most obvious effects on the rectangular slot depth,micro-structured micro-grinding tool could reduce 10%surface roughness and 20%grinding force compared to original micro-grinding tool.Finally,the microchannel array has been machined with a size deviation of 2μm and surface roughness of 0.2μm.展开更多
High-performance 24CrNiMo steel was fabricated using Laser Powder Bed Fusion (LPBF). Subsequent quenching treatment was applied and the influence of quenching temperatures on micro-structure evolution and properties w...High-performance 24CrNiMo steel was fabricated using Laser Powder Bed Fusion (LPBF). Subsequent quenching treatment was applied and the influence of quenching temperatures on micro-structure evolution and properties was systematically characterised and analysed. The micro-structure of the as-built steel consisted of two parts. The first part comprised martensite with twins combined with ω-Fe nano-particles, and the second part consisted of lower bainite in the molten pool, as well as upper bainite, granular bainite and tempered martensite in the heat-affected zone. With the quenching temperatures varying from 800℃ to 950℃, the micro-structure gradually transformed from acicular ferrite + martensite to tempered martensite +θ-Fe3C carbides, and the grain size exhibited noticeable growth. Moreover, quenching treatments could eliminate the anisotropy and inhomogeneity of the micro-structure. The rod-shaped nanosized η-Fe2C and θ-Fe3C precipitates were clearly observed, which were converted from ω-Fe and distributed at multiple angles in the lath. The size and number of nano-precipitates, triggered by the high self-tempering degree of martensite, gradually increased. The relationships among grain size, the twins, dislocation density and nano-precipitation and the dramatically improved performance of quenched samples were analysed using strengthening mechanisms. After quenching at 850℃, the as-built 24CrNiMo steel attained ultra-high mechanical properties including hardness, Ultimate Tensile Strength (UTS), Elongation (El) and impact energy with values of 480.9 HV_(1), 1611.4 MPa, 9.8% and 42.8 J, respectively. Meanwhile, both the wear and thermal fatigue resistance increased by approximately 40%. This study demonstrated that LPBF-fabricated 24CrNiMo steel, with matching good performances, can be achieved using a subsequent one-step quenching process.展开更多
Adopting a nano-and micro-structuring approach to fully unleashing the genuine potential of electrode active material benefits in-depth understandings and research progress toward higher energy density electrochemical...Adopting a nano-and micro-structuring approach to fully unleashing the genuine potential of electrode active material benefits in-depth understandings and research progress toward higher energy density electrochemical energy stor-age devices at all technology readiness levels.Due to various challenging issues,especially limited stability,nano-and micro-structured(NMS)electrodes undergo fast electrochemical performance degradation.The emerging NMS scaffold design is a pivotal aspect of many electrodes as it endows them with both robustness and electrochemical performance enhancement,even though it only occupies comple-mentary and facilitating components for the main mechanism.However,extensive efforts are urgently needed toward optimizing the stereoscopic geometrical design of NMS scaffolds to minimize the volume ratio and maximize their functionality to fulfill the ever-increasing dependency and desire for energy power source supplies.This review will aim at highlighting these NMS scaffold design strategies,summariz-ing their corresponding strengths and challenges,and thereby outlining the potential solutions to resolve these challenges,design principles,and key perspectives for future research in this field.Therefore,this review will be one of the earliest reviews from this viewpoint.展开更多
目的探讨双能量CT Bone Marrow Edema(骨髓水肿)定量评估肋骨骨折演变时间节点的价值。方法收集60例双能量CT扫描的胸部外伤患者,利用CT Bone Marrow Edema技术,标准化定量肋骨骨折处骨髓水肿区域及骨折两侧1 cm处正常区域骨髓CT值,得...目的探讨双能量CT Bone Marrow Edema(骨髓水肿)定量评估肋骨骨折演变时间节点的价值。方法收集60例双能量CT扫描的胸部外伤患者,利用CT Bone Marrow Edema技术,标准化定量肋骨骨折处骨髓水肿区域及骨折两侧1 cm处正常区域骨髓CT值,得到三期骨髓水肿标准化CT值增量与VNCa标准化CT值增量。对数值变量行统计学描述,并对三期骨髓水肿标准化CT值增量、VNCa标准化CT值增量进行各自组间比较及两两间比较,对有差异的组别行诊断效能比较,由接受者工作特征(ROC)曲线下面积(AUC)进行评估,并计算Cut-off值。结果三期骨髓水肿标准化CT值增量及VNCa标准化CT值增量组间均有统计学意义(H=10.788,p=0.005;F=115.787,p=0.000),其中,软骨痂期(纤维性骨痂期)与硬骨痂-重塑期骨髓水肿标准化CT值增量有统计学意义(H=54.958,p=0.003),其余两两间无统计学意义(分别为H=-25.603,p=0.183;H=29.354,p=0.113)。而三期VNCa标准化CT值增量两两间均有统计学意义(P均为0.000)。ROC曲线鉴别软骨痂期(纤维性骨痂期)与硬骨痂-重塑期骨髓水肿标准化CT值增量曲线下面积为0.652,Cut-off值为81.575 Hu,鉴别血肿炎症机化期与软骨痂期(纤维性骨痂期)VNCa标准化CT值增量曲线下面积为0.668,Cut-off值为55.700 Hu,鉴别软骨痂期(纤维性骨痂期)与硬骨痂-重塑期VNCa标准化CT值增量曲线下面积为0.905,Cut-off值为37.625 Hu。结论通过双能量CT Bone Marrow Edema可定量评估肋骨骨折演变时间节点,骨折时间演变的标准化CT值增量差异性可为法医鉴定骨折处于不同时间段提供理论依据。通过标准化CT值增量Cut-off值可一定程度上预测骨折所处时间阶段,为法医在鉴定肋骨骨折方面提供定量依据。展开更多
As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially ...As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially in the context of an imbalance between osteoblast and osteoclast activities.Therefore,the development of new biomaterials has become the key.This article reviews various design strategies and their advantages and disadvantages for biomaterials aimed at osteoporotic bone defects.Overall,current research progress indicates that innovative design,functionalization,and targeting of materials can significantly enhance bone regeneration under osteoporotic conditions.By comprehensively considering biocompatibility,mechanical properties,and bioactivity,these biomaterials can be further optimized,offering a range of choices and strategies for the repair of osteoporotic bone defects.展开更多
Knee osteoarthritis(OA)is a debilitating condition with limited long-term treatment options.The therapeutic potential of mesenchymal stem cells(MSCs),particularly those derived from bone marrow aspirate concentrate,ha...Knee osteoarthritis(OA)is a debilitating condition with limited long-term treatment options.The therapeutic potential of mesenchymal stem cells(MSCs),particularly those derived from bone marrow aspirate concentrate,has garnered attention for cartilage repair in OA.While the iliac crest is the traditional site for bone marrow harvesting(BMH),associated morbidity has prompted the exploration of alternative sites such as the proximal tibia,distal femur,and proximal humerus.This paper reviews the impact of different harvesting sites on mesenchymal stem cell(MSC)yield,viability,and regenerative potential,emphasizing their relevance in knee OA treatment.The iliac crest consistently offers the highest MSC yield,but alternative sites within the surgical field of knee procedures offer comparable MSC characteristics with reduced morbidity.The integration of harvesting techniques into existing knee surgeries,such as total knee arthroplasty,provides a less invasive approach while maintaining thera-peutic efficacy.However,variability in MSC yield from these alternative sites underscores the need for further research to standardize techniques and optimize clinical outcomes.Future directions include large-scale comparative studies,advanced characterization of MSCs,and the development of personalized harvesting strategies.Ultimately,the findings suggest that optimizing the site of BMH can significantly influence the quality of MSC-based therapies for knee OA,enhancing their clinical utility and patient outcomes.展开更多
Following the discovery of bone as an endocrine organ with systemic influence,bone-brain interaction has emerged as a research hotspot,unveiling complex bidirectional communication between bone and brain.Studies indic...Following the discovery of bone as an endocrine organ with systemic influence,bone-brain interaction has emerged as a research hotspot,unveiling complex bidirectional communication between bone and brain.Studies indicate that bone and brain can influence each other’s homeostasis via multiple pathways,yet there is a dearth of systematic reviews in this area.This review comprehensively examines interactions across three key areas:the influence of bone-derived factors on brain function,the effects of brain-related diseases or injuries(BRDI)on bone health,and the concept of skeletal interoception.Additionally,the review discusses innovative approaches in biomaterial design inspired by bone-brain interaction mechanisms,aiming to facilitate bonebrain interactions through materiobiological effects to aid in the treatment of neurodegenerative and bone-related diseases.Notably,the integration of artificial intelligence(AI)in biomaterial design is highlighted,showcasing AI’s role in expediting the formulation of effective and targeted treatment strategies.In conclusion,this review offers vital insights into the mechanisms of bone-brain interaction and suggests advanced approaches to harness these interactions in clinical practice.These insights offer promising avenues for preventing and treating complex diseases impacting the skeleton and brain,underscoring the potential of interdisciplinary approaches in enhancing human health.展开更多
The delicate balance between bone formation by osteoblasts and bone resorption by osteoclasts maintains bone homeostasis.Nuclear receptors(NRs)are now understood to be crucial in bone physiology and pathology.However,...The delicate balance between bone formation by osteoblasts and bone resorption by osteoclasts maintains bone homeostasis.Nuclear receptors(NRs)are now understood to be crucial in bone physiology and pathology.However,the function of the Farnesoid X receptor(FXR),a member of the NR family,in regulating bone homeostasis remains incompletely understood.In this study,in vitro and in vivo models revealed delayed bone development and an osteoporosis phenotype in mice lacking FXR in bone marrow mesenchymal stem cells(BMSCs)and osteoblasts due to impaired osteoblast differentiation.Mechanistically,FXR could stabilize RUNX2 by inhibiting Thoc6-mediated ubiquitination,thereby promoting osteogenic activity in BMSCs.Moreover,activated FXR could directly bind to the Thoc6 promoter,suppressing its expression.The interaction between RUNX2 and Thoc6 was mediated by the Runt domain of RUNX2 and the WD repeat of Thoc6.Additionally,Obeticholic acid(OCA),an orally available FXR agonist,could ameliorate bone loss in an ovariectomy(OVX)-induced osteoporotic mouse model.Taken together,our findings suggest that FXR plays pivotal roles in osteoblast differentiation by regulating RUNX2 stability and that targeting FXR may be a promising therapeutic approach for osteoporosis.展开更多
Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to impr...Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are unknown.To this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB pathways.Subsequently,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by asphyxia.The results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these effects.To conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.展开更多
The incidence of large bone defects caused by traumatic injury is increasing worldwide,and the tissue regeneration process requires a long recovery time due to limited self-healing capability.Endogenous bioelectrical ...The incidence of large bone defects caused by traumatic injury is increasing worldwide,and the tissue regeneration process requires a long recovery time due to limited self-healing capability.Endogenous bioelectrical phenomena have been well recognized as critical biophysical factors in bone remodeling and regeneration.Inspired by bioelectricity,electrical stimulation has been widely considered an external intervention to induce the osteogenic lineage of cells and enhance the synthesis of the extracellular matrix,thereby accelerating bone regeneration.With ongoing advances in biomaterials and energy-harvesting techniques,electroactive biomaterials and self-powered systems have been considered biomimetic approaches to ensure functional recovery by recapitulating the natural electrophysiological microenvironment of healthy bone tissue.In this review,we first introduce the role of bioelectricity and the endogenous electric field in bone tissue and summarize different techniques to electrically stimulate cells and tissue.Next,we highlight the latest progress in exploring electroactive hybrid biomaterials as well as self-powered systems such as triboelectric and piezoelectric-based nanogenerators and photovoltaic cell-based devices and their implementation in bone tissue engineering.Finally,we emphasize the significance of simulating the target tissue’s electrophysiological microenvironment and propose the opportunities and challenges faced by electroactive hybrid biomaterials and self-powered bioelectronics for bone repair strategies.展开更多
Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was dimini...Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was diminished in the bone of aged and ovariectomized(OVX)mice,as well as in the serum of osteopenia and osteoporosis patients.In vitro loss-of-function and gain-offunction studies revealed that NELL2 facilitated osteoblast differentiation and impeded adipocyte differentiation from stromal progenitor cells.In vivo studies further demonstrated that the deletion of NELL2 in preosteoblasts resulted in decreased cancellous bone mass in mice.Mechanistically,NELL2 interacted with the FNI-type domain located at the C-terminus of Fibronectin 1(Fn1).Moreover,we found that NELL2 activated the focal adhesion kinase(FAK)/AKT signaling pathway through Fn1/integrinβ1(ITGB1),leading to the promotion of osteogenesis and the inhibition of adipogenesis.Notably,administration of NELL2-AAV was found to ameliorate bone loss in OVX mice.These findings underscore the significant role of NELL2 in osteoblast differentiation and bone homeostasis,suggesting its potential as a therapeutic target for managing osteoporosis.展开更多
Bone age assessment(BAA)aims to determine whether a child’s growth and development are normal concerning their chronological age.To predict bone age more accurately based on radiographs,and for the left-hand X-ray im...Bone age assessment(BAA)aims to determine whether a child’s growth and development are normal concerning their chronological age.To predict bone age more accurately based on radiographs,and for the left-hand X-ray images of different races model can have better adaptability,we propose a neural network in parallel with the quantitative features from the left-hand bone measurements for BAA.In this study,a lightweight feature extractor(LFE)is designed to obtain the featuremaps fromradiographs,and amodule called attention erasermodule(AEM)is proposed to capture the fine-grained features.Meanwhile,the dimensional information of the metacarpal parts in the radiographs is measured to enhance the model’s generalization capability across images fromdifferent races.Ourmodel is trained and validated on the RSNA,RHPE,and digital hand atlas datasets,which include images from various racial groups.The model achieves a mean absolute error(MAE)of 4.42 months on the RSNA dataset and 15.98 months on the RHPE dataset.Compared to ResNet50,InceptionV3,and several state-of-the-art methods,our proposed method shows statistically significant improvements(p<0.05),with a reduction in MAE by 0.2±0.02 years across different racial datasets.Furthermore,t-tests on the features also confirm the statistical significance of our approach(p<0.05).展开更多
BACKGROUND The induced-membrane technique was initially described by Masquelet as an effective treatment for large bone defects,especially those caused by infection.Here,we report a case of chronic osteomyelitis of th...BACKGROUND The induced-membrane technique was initially described by Masquelet as an effective treatment for large bone defects,especially those caused by infection.Here,we report a case of chronic osteomyelitis of the radius associated with a 9 cm bone defect,which was filled with a large allogeneic cortical bone graft from a bone bank.Complete bony union was achieved after 14 months of follow-up.Previous studies have used autogenous bone as the primary bone source for the Masquelet technique;in our case,the exclusive use of allografts is as successful as the use of autologous bone grafts.With the advent of bone banks,it is possible to obtain an unlimited amount of allograft,and the Masquelet technique may be further improved based on this new way of bone grafting.CASE SUMMARY In this study,we reported a case of repair of a long bone defect in a 40-year-old male patient,which was characterized by the utilization of allograft cortical bone combined with the Masquelet technique for the treatment of the patient's long bone defect in the forearm.The patient's results of functional recovery of the forearm were surprising,which further deepens the scope of application of Masquelet technique and helps to strengthen the efficacy of Masquelet technique in the treatment of long bones indeed.CONCLUSION Allograft cortical bone combined with the Masquelet technique provides a new method of treatment to large bone defect.展开更多
Bioactive molecules have shown great promise for effectively regulating various bone formation processes,rendering them attractive therapeutics for bone regeneration.However,the widespread application of bioactive mol...Bioactive molecules have shown great promise for effectively regulating various bone formation processes,rendering them attractive therapeutics for bone regeneration.However,the widespread application of bioactive molecules is limited by their low accumulation and short half-lives in vivo.Hydrogels have emerged as ideal carriers to address these challenges,offering the potential to prolong retention times at lesion sites,extend half-lives in vivo and mitigate side effects,avoid burst release,and promote adsorption under physiological conditions.This review systematically summarizes the recent advances in the development of bioactive molecule-loaded hydrogels for bone regeneration,encompassing applications in cranial defect repair,femoral defect repair,periodontal bone regeneration,and bone regeneration with underlying diseases.Additionally,this review discusses the current strategies aimed at improving the release profiles of bioactive molecules through stimuli-responsive delivery,carrier-assisted delivery,and sequential delivery.Finally,this review elucidates the existing challenges and future directions of hydrogel encapsulated bioactive molecules in the field of bone regeneration.展开更多
Autologous bone marrow-derived mesenchymal stem cells(BMSCs)have been shown to promote osteogenesis;however,the effects of allogeneic BMSCs(allo-BMSCs)on bone regeneration remain unclear.Therefore,we explored the bone...Autologous bone marrow-derived mesenchymal stem cells(BMSCs)have been shown to promote osteogenesis;however,the effects of allogeneic BMSCs(allo-BMSCs)on bone regeneration remain unclear.Therefore,we explored the bone regeneration promotion effect of allo-BMSCs in 3D-printed autologous bone particle(ABP)scaffolds.First,we concurrently printed scaffolds with polycaprolactone,ABPs,and allo-BMSCs for appropriate support,providing bioactive factors and seed cells to promote osteogenesis.In vitro studies showed that ABP scaffolds promoted allo-BMSC osteogenic differentiation.In vivo studies revealed that the implantation of scaffolds loaded with ABPs and allo-BMSCs into canine skull defects for nine months promoted osteogenesis.Further experiments suggested that only a small portion of implanted allo-BMSCs survived and differentiated into vascular endothelial cells,chondrocytes,and osteocytes.The implanted allo-BMSCs released stromal cell-derived factor 1 through paracrine signaling to recruit native BMSCs into the defect,promoting bone regeneration.This study contributes to our understanding of allo-BMSCs,providing information relevant to their future application.展开更多
Bone metastasis is the primary cause of mortality in breast cancer(BC)patients.The present study elucidates the functional role of the differentiated embryonic chondrocyte-expressed gene 1(DEC1)in promoting BC-related...Bone metastasis is the primary cause of mortality in breast cancer(BC)patients.The present study elucidates the functional role of the differentiated embryonic chondrocyte-expressed gene 1(DEC1)in promoting BC-related bone metastasis.Analysis of patient-derived samples and public databases revealed a significant upregulation of DEC1 and CXCR4 in breast tumors compared with adjacent normal tissues,with elevated levels correlating with increased metastatic potential,suggesting their synergistic involvement in BC progression.Intracardiac injection experiments demonstrated that Dec1-WT 4T1 cells induced more severe osteolysis and larger metastatic lesions than Dec1-KD 4T1 cells.In MDA-MB-231 cells,DEC1 overexpression(OE)upregulated CXCR4 and proliferation/migration-related genes,whereas DEC1 knockdown reversed these effects.Notably,AMD3100,a specific CXCR4 antagonist,partially reversed the DEC1-OE-induced upregulation of CXCR4 and associated pro-metastatic genes.Mechanistically,DEC1 bound to the CXCR4 promoter region(-230 to-326)and activated its transcription,corroborated by ChIP-seq data.Furthermore,pharmacological inhibition of AKT(LY294002)or JAK2(AZD1480),but not ERK(PD98059),attenuated DEC1-mediated CXCR4 upregulation,although all three inhibitors mitigated DEC1-driven migration-related gene expression.Additionally,DEC1 enhanced CXCL12 secretion from mesenchymal stromal cells and osteoblasts,amplifying the CXCR4/CXCL12 axis within the bone microenvironment.Collectively,our findings demonstrate that DEC1 promotes BC bone metastasis by directly transactivating CXCR4 expression,providing a molecular basis for targeting DEC1 to prevent and treat BC bone metastasis.展开更多
The injection of bone cement is a promising surgical intervention for the treatment of osteoporosis.The aim of this study was to formulate a novel injectable bioactive bone cement to adress such medical problems.The b...The injection of bone cement is a promising surgical intervention for the treatment of osteoporosis.The aim of this study was to formulate a novel injectable bioactive bone cement to adress such medical problems.The bone cement primarily consists of tricalcium phosphate(β-TCP),konjac glucomannan(KGM),and hydroxyapatite whisker(HAw).An orthogonal experiment was designed to generate multiple sets of new composite calcium phosphate cement(NCPC)samples,and their setting times were measured.The in vitro compatibility of the new bone cement was assessed through relative cell proliferation rate(RGR)and in vitro cell growth experiments.Mechanical strength and porosity tests were conducted for each group of bone cement,and cross-sectional morphology was observed.The results demonstrate that the bone cement exhibits favorable properties such as self-curing,mechanical robustness,and resistance to collapse.The optimum formulation involves a doping ratio of 5/15(wt%)HAw and HA,an additional amount of 1.2wt%KGM,and a liquid citric acid concentration of 2wt%.Porosity tests confirmed that the material has high compressive strength and a favorable porosity of 27%,creating conducive conditions for cell growth,proliferation,and material degradation.Moreover,in vitro cell culture experiments revealed excellent biocompatibility of the material.Consequently,the developed NCPC emerges as a potential candidate material for applications of bone implantation.展开更多
Prostate cancer is one of the most common cancers among males worldwide and a common cause of cancer related mortality in males. Bone metastasis from prostate cancer is common in advanced stage disease leading to majo...Prostate cancer is one of the most common cancers among males worldwide and a common cause of cancer related mortality in males. Bone metastasis from prostate cancer is common in advanced stage disease leading to major complications including severe bone pain and fractures. Here, we present a case of 79-year-old male newly diagnosed metastatic prostate cancer, with metastasis to the lungs, liver and lymph nodes, and a solitary osteolytic bone metastasis seen in bone scan. It is well known that osseous metastasis from prostate cancer is primarily sclerotic, although lytic bone metastasis is rare, but it can also be seen as in our case.展开更多
Large bone defects in load-bearing bone can result from tumor resection,osteomyelitis,trauma,and other factors.Although bone has the intrinsic potential to self-repair and regenerate,the repair of large bone defects w...Large bone defects in load-bearing bone can result from tumor resection,osteomyelitis,trauma,and other factors.Although bone has the intrinsic potential to self-repair and regenerate,the repair of large bone defects which exceed a certain critical size remains a substantial clinical challenge.Traditionally,repair methods involve using autologous or allogeneic bone tissue to replace the lost bone tissue at defect sites,and autogenous bone grafting remains the“gold standard”treatment.However,the application of traditional bone grafts is limited by drawbacks such as the quantity of extractable bone,donor-site morbidities,and the risk of rejection.In recent years,the clinical demand for alternatives to traditional bone grafts has promoted the development of novel bone-grafting substitutes.In addition to osteoconductivity and osteoinductivity,optimal mechanical properties have recently been the focus of efforts to improve the treatment success of novel bone-grafting alternatives in load-bearing bone defects,but most biomaterial synthetic scaffolds cannot provide sufficient mechanical strength.A fundamental challenge is to find an appropriate balance between mechanical and tissue-regeneration requirements.In this review,the use of traditional bone grafts in load-bearing bone defects,as well as their advantages and disadvantages,is summarized and reviewed.Furthermore,we highlight recent development strategies for novel bone grafts appropriate for load-bearing bone defects based on substance,structural,and functional bionics to provide ideas and directions for future research.展开更多
Maxillary bone loss impairs essential functions (chewing, swallowing, speech) and gives patients a very unaesthetic appearance due to the removal of facial support tissues, leading to serious psychological consequence...Maxillary bone loss impairs essential functions (chewing, swallowing, speech) and gives patients a very unaesthetic appearance due to the removal of facial support tissues, leading to serious psychological consequences. Treatment is multidisciplinary and requires a resective surgery if the cause is tumor-related, or an additive surgery if the cause is traumatic. This article aims to show the role of making a prosthesis to restore function (chewing, swallowing, speech) and aesthetics following maxillary bone loss. We will eighter present a clinical case involving a right maxillary tumor that was surgically resected followed by radiotherapy, and subsequently rehabilitated with a maxillofacial prosthesis in the consultation and dental treatment center of the university hospital center of Casablanca.展开更多
基金co-supported by the Enterprise Innovation and Development Joint Program of the National Natural Science Foundation of China(No.U20B2032)Open Project Funding of State Key Laboratory for High Performance Tools(GXNGJSKL-2024-08)+1 种基金Open Foundation of the State Key Laboratory of Intelligent Manufacturing Equipment and Technology(IMETKF2023005)Introduced Innovative Scientific Research Team Project of Zhongshan(the tenth batch)(CXTD2023008)。
文摘Micro-grinding has been widely used in aerospace and other industry.However,the small diameter of the micro-grinding tool has limited its machining performance and efficiency.In order to solve the above problems,micro-structure has been applied on the micro-grinding tool.A morphology modeling has been established in this study to characterize the surface of microstructured micro-grinding tool,and the grinding performance of micro-structured micro-grinding tool has been analyzed through undeformed chip thickness,abrasive edge width,and effective distance between abrasives.Then deviation analysis,path optimization and parameter optimization of microchannel array precision grinding have been finished to improve processing quality and efficiency,and the deflection angle has the most obvious effects on the rectangular slot depth,micro-structured micro-grinding tool could reduce 10%surface roughness and 20%grinding force compared to original micro-grinding tool.Finally,the microchannel array has been machined with a size deviation of 2μm and surface roughness of 0.2μm.
基金co-supported by the National Key Research and Development Program of China (No. 2022YFB4600500)the National Natural Science Foundation of China (No. 52235006)
文摘High-performance 24CrNiMo steel was fabricated using Laser Powder Bed Fusion (LPBF). Subsequent quenching treatment was applied and the influence of quenching temperatures on micro-structure evolution and properties was systematically characterised and analysed. The micro-structure of the as-built steel consisted of two parts. The first part comprised martensite with twins combined with ω-Fe nano-particles, and the second part consisted of lower bainite in the molten pool, as well as upper bainite, granular bainite and tempered martensite in the heat-affected zone. With the quenching temperatures varying from 800℃ to 950℃, the micro-structure gradually transformed from acicular ferrite + martensite to tempered martensite +θ-Fe3C carbides, and the grain size exhibited noticeable growth. Moreover, quenching treatments could eliminate the anisotropy and inhomogeneity of the micro-structure. The rod-shaped nanosized η-Fe2C and θ-Fe3C precipitates were clearly observed, which were converted from ω-Fe and distributed at multiple angles in the lath. The size and number of nano-precipitates, triggered by the high self-tempering degree of martensite, gradually increased. The relationships among grain size, the twins, dislocation density and nano-precipitation and the dramatically improved performance of quenched samples were analysed using strengthening mechanisms. After quenching at 850℃, the as-built 24CrNiMo steel attained ultra-high mechanical properties including hardness, Ultimate Tensile Strength (UTS), Elongation (El) and impact energy with values of 480.9 HV_(1), 1611.4 MPa, 9.8% and 42.8 J, respectively. Meanwhile, both the wear and thermal fatigue resistance increased by approximately 40%. This study demonstrated that LPBF-fabricated 24CrNiMo steel, with matching good performances, can be achieved using a subsequent one-step quenching process.
基金The authors acknowledge support from the German Research Foundation(DFG:LE 2249/5-1)the Sino-German Center for Research Promotion(GZ1579)+1 种基金Yunnan Fundamental Research Projects(202201AW070014)Jiajia Qiu and Yu Duan appreciate support from the China Scholarship Council(No.201908530218&202206990027).
文摘Adopting a nano-and micro-structuring approach to fully unleashing the genuine potential of electrode active material benefits in-depth understandings and research progress toward higher energy density electrochemical energy stor-age devices at all technology readiness levels.Due to various challenging issues,especially limited stability,nano-and micro-structured(NMS)electrodes undergo fast electrochemical performance degradation.The emerging NMS scaffold design is a pivotal aspect of many electrodes as it endows them with both robustness and electrochemical performance enhancement,even though it only occupies comple-mentary and facilitating components for the main mechanism.However,extensive efforts are urgently needed toward optimizing the stereoscopic geometrical design of NMS scaffolds to minimize the volume ratio and maximize their functionality to fulfill the ever-increasing dependency and desire for energy power source supplies.This review will aim at highlighting these NMS scaffold design strategies,summariz-ing their corresponding strengths and challenges,and thereby outlining the potential solutions to resolve these challenges,design principles,and key perspectives for future research in this field.Therefore,this review will be one of the earliest reviews from this viewpoint.
文摘目的探讨双能量CT Bone Marrow Edema(骨髓水肿)定量评估肋骨骨折演变时间节点的价值。方法收集60例双能量CT扫描的胸部外伤患者,利用CT Bone Marrow Edema技术,标准化定量肋骨骨折处骨髓水肿区域及骨折两侧1 cm处正常区域骨髓CT值,得到三期骨髓水肿标准化CT值增量与VNCa标准化CT值增量。对数值变量行统计学描述,并对三期骨髓水肿标准化CT值增量、VNCa标准化CT值增量进行各自组间比较及两两间比较,对有差异的组别行诊断效能比较,由接受者工作特征(ROC)曲线下面积(AUC)进行评估,并计算Cut-off值。结果三期骨髓水肿标准化CT值增量及VNCa标准化CT值增量组间均有统计学意义(H=10.788,p=0.005;F=115.787,p=0.000),其中,软骨痂期(纤维性骨痂期)与硬骨痂-重塑期骨髓水肿标准化CT值增量有统计学意义(H=54.958,p=0.003),其余两两间无统计学意义(分别为H=-25.603,p=0.183;H=29.354,p=0.113)。而三期VNCa标准化CT值增量两两间均有统计学意义(P均为0.000)。ROC曲线鉴别软骨痂期(纤维性骨痂期)与硬骨痂-重塑期骨髓水肿标准化CT值增量曲线下面积为0.652,Cut-off值为81.575 Hu,鉴别血肿炎症机化期与软骨痂期(纤维性骨痂期)VNCa标准化CT值增量曲线下面积为0.668,Cut-off值为55.700 Hu,鉴别软骨痂期(纤维性骨痂期)与硬骨痂-重塑期VNCa标准化CT值增量曲线下面积为0.905,Cut-off值为37.625 Hu。结论通过双能量CT Bone Marrow Edema可定量评估肋骨骨折演变时间节点,骨折时间演变的标准化CT值增量差异性可为法医鉴定骨折处于不同时间段提供理论依据。通过标准化CT值增量Cut-off值可一定程度上预测骨折所处时间阶段,为法医在鉴定肋骨骨折方面提供定量依据。
基金supported by the National Natural Science Foundation of China(Nos.82160419 and 82302772)Guizhou Basic Research Project(No.ZK[2023]General 201)。
文摘As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially in the context of an imbalance between osteoblast and osteoclast activities.Therefore,the development of new biomaterials has become the key.This article reviews various design strategies and their advantages and disadvantages for biomaterials aimed at osteoporotic bone defects.Overall,current research progress indicates that innovative design,functionalization,and targeting of materials can significantly enhance bone regeneration under osteoporotic conditions.By comprehensively considering biocompatibility,mechanical properties,and bioactivity,these biomaterials can be further optimized,offering a range of choices and strategies for the repair of osteoporotic bone defects.
文摘Knee osteoarthritis(OA)is a debilitating condition with limited long-term treatment options.The therapeutic potential of mesenchymal stem cells(MSCs),particularly those derived from bone marrow aspirate concentrate,has garnered attention for cartilage repair in OA.While the iliac crest is the traditional site for bone marrow harvesting(BMH),associated morbidity has prompted the exploration of alternative sites such as the proximal tibia,distal femur,and proximal humerus.This paper reviews the impact of different harvesting sites on mesenchymal stem cell(MSC)yield,viability,and regenerative potential,emphasizing their relevance in knee OA treatment.The iliac crest consistently offers the highest MSC yield,but alternative sites within the surgical field of knee procedures offer comparable MSC characteristics with reduced morbidity.The integration of harvesting techniques into existing knee surgeries,such as total knee arthroplasty,provides a less invasive approach while maintaining thera-peutic efficacy.However,variability in MSC yield from these alternative sites underscores the need for further research to standardize techniques and optimize clinical outcomes.Future directions include large-scale comparative studies,advanced characterization of MSCs,and the development of personalized harvesting strategies.Ultimately,the findings suggest that optimizing the site of BMH can significantly influence the quality of MSC-based therapies for knee OA,enhancing their clinical utility and patient outcomes.
基金financially supported by the Basic Science Center Program(T2288102)the Key Program of the National Natural Science Foundation of China(32230059)+3 种基金the Foundation of Frontiers Science Center for Materiobiology and Dynamic Chemistry(JKVD1211002)the Project supported by the Young Scientists Fund of the National Natural Science Foundation of China(32401128)Postdoctoral Fellowship Program of CPSF(GZC20230793)Shanghai Post-doctoral Excellence Program(2023251).
文摘Following the discovery of bone as an endocrine organ with systemic influence,bone-brain interaction has emerged as a research hotspot,unveiling complex bidirectional communication between bone and brain.Studies indicate that bone and brain can influence each other’s homeostasis via multiple pathways,yet there is a dearth of systematic reviews in this area.This review comprehensively examines interactions across three key areas:the influence of bone-derived factors on brain function,the effects of brain-related diseases or injuries(BRDI)on bone health,and the concept of skeletal interoception.Additionally,the review discusses innovative approaches in biomaterial design inspired by bone-brain interaction mechanisms,aiming to facilitate bonebrain interactions through materiobiological effects to aid in the treatment of neurodegenerative and bone-related diseases.Notably,the integration of artificial intelligence(AI)in biomaterial design is highlighted,showcasing AI’s role in expediting the formulation of effective and targeted treatment strategies.In conclusion,this review offers vital insights into the mechanisms of bone-brain interaction and suggests advanced approaches to harness these interactions in clinical practice.These insights offer promising avenues for preventing and treating complex diseases impacting the skeleton and brain,underscoring the potential of interdisciplinary approaches in enhancing human health.
基金supported by National Natural Science Foundation of China(grant numbers 82072523 to Zhiyong Hou)Postdoctoral program of Clinical medicine of Hebei Medical University(grant numbers PD2023012 to Sujuan Xu)+2 种基金Excellent postdoctoral research funding project of Hebei Province(grant numbers B2023005011 to Sujuan Xu)The 16th special grant of China Postdoctoral Science Foundation(grant numbers 2023T160182 to Sujuan Xu)Natural Science Foundation of Hebei Province,China(grant numbers H2023206230 to Yingchao Yin,H2024206186 to Sujuan Xu).
文摘The delicate balance between bone formation by osteoblasts and bone resorption by osteoclasts maintains bone homeostasis.Nuclear receptors(NRs)are now understood to be crucial in bone physiology and pathology.However,the function of the Farnesoid X receptor(FXR),a member of the NR family,in regulating bone homeostasis remains incompletely understood.In this study,in vitro and in vivo models revealed delayed bone development and an osteoporosis phenotype in mice lacking FXR in bone marrow mesenchymal stem cells(BMSCs)and osteoblasts due to impaired osteoblast differentiation.Mechanistically,FXR could stabilize RUNX2 by inhibiting Thoc6-mediated ubiquitination,thereby promoting osteogenic activity in BMSCs.Moreover,activated FXR could directly bind to the Thoc6 promoter,suppressing its expression.The interaction between RUNX2 and Thoc6 was mediated by the Runt domain of RUNX2 and the WD repeat of Thoc6.Additionally,Obeticholic acid(OCA),an orally available FXR agonist,could ameliorate bone loss in an ovariectomy(OVX)-induced osteoporotic mouse model.Taken together,our findings suggest that FXR plays pivotal roles in osteoblast differentiation by regulating RUNX2 stability and that targeting FXR may be a promising therapeutic approach for osteoporosis.
基金supported by the Natural Science Fund of Fujian Province,No.2020J011058(to JK)the Project of Fujian Provincial Hospital for High-level Hospital Construction,No.2020HSJJ12(to JK)+1 种基金the Fujian Provincial Finance Department Special Fund,No.(2021)848(to FC)the Fujian Provincial Major Scientific and Technological Special Projects on Health,No.2022ZD01008(to FC).
文摘Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are unknown.To this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB pathways.Subsequently,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by asphyxia.The results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these effects.To conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.
基金support of the National Natural Science Foundation of China(Grant No.52205593)Shaanxi Natural Science Foundation Project(2024JC-YBMS-711).
文摘The incidence of large bone defects caused by traumatic injury is increasing worldwide,and the tissue regeneration process requires a long recovery time due to limited self-healing capability.Endogenous bioelectrical phenomena have been well recognized as critical biophysical factors in bone remodeling and regeneration.Inspired by bioelectricity,electrical stimulation has been widely considered an external intervention to induce the osteogenic lineage of cells and enhance the synthesis of the extracellular matrix,thereby accelerating bone regeneration.With ongoing advances in biomaterials and energy-harvesting techniques,electroactive biomaterials and self-powered systems have been considered biomimetic approaches to ensure functional recovery by recapitulating the natural electrophysiological microenvironment of healthy bone tissue.In this review,we first introduce the role of bioelectricity and the endogenous electric field in bone tissue and summarize different techniques to electrically stimulate cells and tissue.Next,we highlight the latest progress in exploring electroactive hybrid biomaterials as well as self-powered systems such as triboelectric and piezoelectric-based nanogenerators and photovoltaic cell-based devices and their implementation in bone tissue engineering.Finally,we emphasize the significance of simulating the target tissue’s electrophysiological microenvironment and propose the opportunities and challenges faced by electroactive hybrid biomaterials and self-powered bioelectronics for bone repair strategies.
基金supported by grants from National Natural Science Foundation of China(82272444,81972031,81972033)China Postdoctoral Science Foundation(2022M722382)Tianjin Key Medical Discipline(Specialty)Construction Project(TJYXZDXK-032A)。
文摘Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was diminished in the bone of aged and ovariectomized(OVX)mice,as well as in the serum of osteopenia and osteoporosis patients.In vitro loss-of-function and gain-offunction studies revealed that NELL2 facilitated osteoblast differentiation and impeded adipocyte differentiation from stromal progenitor cells.In vivo studies further demonstrated that the deletion of NELL2 in preosteoblasts resulted in decreased cancellous bone mass in mice.Mechanistically,NELL2 interacted with the FNI-type domain located at the C-terminus of Fibronectin 1(Fn1).Moreover,we found that NELL2 activated the focal adhesion kinase(FAK)/AKT signaling pathway through Fn1/integrinβ1(ITGB1),leading to the promotion of osteogenesis and the inhibition of adipogenesis.Notably,administration of NELL2-AAV was found to ameliorate bone loss in OVX mice.These findings underscore the significant role of NELL2 in osteoblast differentiation and bone homeostasis,suggesting its potential as a therapeutic target for managing osteoporosis.
基金supported by the grant from the National Natural Science Foundation of China(No.72071019)grant from the Natural Science Foundation of Chongqing(No.cstc2021jcyj-msxmX0185).
文摘Bone age assessment(BAA)aims to determine whether a child’s growth and development are normal concerning their chronological age.To predict bone age more accurately based on radiographs,and for the left-hand X-ray images of different races model can have better adaptability,we propose a neural network in parallel with the quantitative features from the left-hand bone measurements for BAA.In this study,a lightweight feature extractor(LFE)is designed to obtain the featuremaps fromradiographs,and amodule called attention erasermodule(AEM)is proposed to capture the fine-grained features.Meanwhile,the dimensional information of the metacarpal parts in the radiographs is measured to enhance the model’s generalization capability across images fromdifferent races.Ourmodel is trained and validated on the RSNA,RHPE,and digital hand atlas datasets,which include images from various racial groups.The model achieves a mean absolute error(MAE)of 4.42 months on the RSNA dataset and 15.98 months on the RHPE dataset.Compared to ResNet50,InceptionV3,and several state-of-the-art methods,our proposed method shows statistically significant improvements(p<0.05),with a reduction in MAE by 0.2±0.02 years across different racial datasets.Furthermore,t-tests on the features also confirm the statistical significance of our approach(p<0.05).
文摘BACKGROUND The induced-membrane technique was initially described by Masquelet as an effective treatment for large bone defects,especially those caused by infection.Here,we report a case of chronic osteomyelitis of the radius associated with a 9 cm bone defect,which was filled with a large allogeneic cortical bone graft from a bone bank.Complete bony union was achieved after 14 months of follow-up.Previous studies have used autogenous bone as the primary bone source for the Masquelet technique;in our case,the exclusive use of allografts is as successful as the use of autologous bone grafts.With the advent of bone banks,it is possible to obtain an unlimited amount of allograft,and the Masquelet technique may be further improved based on this new way of bone grafting.CASE SUMMARY In this study,we reported a case of repair of a long bone defect in a 40-year-old male patient,which was characterized by the utilization of allograft cortical bone combined with the Masquelet technique for the treatment of the patient's long bone defect in the forearm.The patient's results of functional recovery of the forearm were surprising,which further deepens the scope of application of Masquelet technique and helps to strengthen the efficacy of Masquelet technique in the treatment of long bones indeed.CONCLUSION Allograft cortical bone combined with the Masquelet technique provides a new method of treatment to large bone defect.
基金supported by the National Natural Science Foundation of China(51925304)Natural Science Foundation of Sichuan Province(2024NSFSC1023)Medical Research Program of Sichuan Province(Q23015).
文摘Bioactive molecules have shown great promise for effectively regulating various bone formation processes,rendering them attractive therapeutics for bone regeneration.However,the widespread application of bioactive molecules is limited by their low accumulation and short half-lives in vivo.Hydrogels have emerged as ideal carriers to address these challenges,offering the potential to prolong retention times at lesion sites,extend half-lives in vivo and mitigate side effects,avoid burst release,and promote adsorption under physiological conditions.This review systematically summarizes the recent advances in the development of bioactive molecule-loaded hydrogels for bone regeneration,encompassing applications in cranial defect repair,femoral defect repair,periodontal bone regeneration,and bone regeneration with underlying diseases.Additionally,this review discusses the current strategies aimed at improving the release profiles of bioactive molecules through stimuli-responsive delivery,carrier-assisted delivery,and sequential delivery.Finally,this review elucidates the existing challenges and future directions of hydrogel encapsulated bioactive molecules in the field of bone regeneration.
基金supported by the Science and Technology Development Fund of the Fourth Military Medical University(No.2016XB051)the Military Medical Promotion Plan of the Fourth Military Medical University(No.2016TSA-005)+2 种基金the Science and Technology Program of Guangzhou(No.201604040002)the Youth Development Project of Air Force Medical University(No.21QNPY072)the Xijing Hospital Booster Program(No.XJZT24CZ10).
文摘Autologous bone marrow-derived mesenchymal stem cells(BMSCs)have been shown to promote osteogenesis;however,the effects of allogeneic BMSCs(allo-BMSCs)on bone regeneration remain unclear.Therefore,we explored the bone regeneration promotion effect of allo-BMSCs in 3D-printed autologous bone particle(ABP)scaffolds.First,we concurrently printed scaffolds with polycaprolactone,ABPs,and allo-BMSCs for appropriate support,providing bioactive factors and seed cells to promote osteogenesis.In vitro studies showed that ABP scaffolds promoted allo-BMSC osteogenic differentiation.In vivo studies revealed that the implantation of scaffolds loaded with ABPs and allo-BMSCs into canine skull defects for nine months promoted osteogenesis.Further experiments suggested that only a small portion of implanted allo-BMSCs survived and differentiated into vascular endothelial cells,chondrocytes,and osteocytes.The implanted allo-BMSCs released stromal cell-derived factor 1 through paracrine signaling to recruit native BMSCs into the defect,promoting bone regeneration.This study contributes to our understanding of allo-BMSCs,providing information relevant to their future application.
基金supported by the Natural Science Foundation of China(Grant Nos.82073934,81872937)Office of Jiangsu Provincial Academic Degrees Committee(Grant No.JX10114120).
文摘Bone metastasis is the primary cause of mortality in breast cancer(BC)patients.The present study elucidates the functional role of the differentiated embryonic chondrocyte-expressed gene 1(DEC1)in promoting BC-related bone metastasis.Analysis of patient-derived samples and public databases revealed a significant upregulation of DEC1 and CXCR4 in breast tumors compared with adjacent normal tissues,with elevated levels correlating with increased metastatic potential,suggesting their synergistic involvement in BC progression.Intracardiac injection experiments demonstrated that Dec1-WT 4T1 cells induced more severe osteolysis and larger metastatic lesions than Dec1-KD 4T1 cells.In MDA-MB-231 cells,DEC1 overexpression(OE)upregulated CXCR4 and proliferation/migration-related genes,whereas DEC1 knockdown reversed these effects.Notably,AMD3100,a specific CXCR4 antagonist,partially reversed the DEC1-OE-induced upregulation of CXCR4 and associated pro-metastatic genes.Mechanistically,DEC1 bound to the CXCR4 promoter region(-230 to-326)and activated its transcription,corroborated by ChIP-seq data.Furthermore,pharmacological inhibition of AKT(LY294002)or JAK2(AZD1480),but not ERK(PD98059),attenuated DEC1-mediated CXCR4 upregulation,although all three inhibitors mitigated DEC1-driven migration-related gene expression.Additionally,DEC1 enhanced CXCL12 secretion from mesenchymal stromal cells and osteoblasts,amplifying the CXCR4/CXCL12 axis within the bone microenvironment.Collectively,our findings demonstrate that DEC1 promotes BC bone metastasis by directly transactivating CXCR4 expression,providing a molecular basis for targeting DEC1 to prevent and treat BC bone metastasis.
文摘The injection of bone cement is a promising surgical intervention for the treatment of osteoporosis.The aim of this study was to formulate a novel injectable bioactive bone cement to adress such medical problems.The bone cement primarily consists of tricalcium phosphate(β-TCP),konjac glucomannan(KGM),and hydroxyapatite whisker(HAw).An orthogonal experiment was designed to generate multiple sets of new composite calcium phosphate cement(NCPC)samples,and their setting times were measured.The in vitro compatibility of the new bone cement was assessed through relative cell proliferation rate(RGR)and in vitro cell growth experiments.Mechanical strength and porosity tests were conducted for each group of bone cement,and cross-sectional morphology was observed.The results demonstrate that the bone cement exhibits favorable properties such as self-curing,mechanical robustness,and resistance to collapse.The optimum formulation involves a doping ratio of 5/15(wt%)HAw and HA,an additional amount of 1.2wt%KGM,and a liquid citric acid concentration of 2wt%.Porosity tests confirmed that the material has high compressive strength and a favorable porosity of 27%,creating conducive conditions for cell growth,proliferation,and material degradation.Moreover,in vitro cell culture experiments revealed excellent biocompatibility of the material.Consequently,the developed NCPC emerges as a potential candidate material for applications of bone implantation.
文摘Prostate cancer is one of the most common cancers among males worldwide and a common cause of cancer related mortality in males. Bone metastasis from prostate cancer is common in advanced stage disease leading to major complications including severe bone pain and fractures. Here, we present a case of 79-year-old male newly diagnosed metastatic prostate cancer, with metastasis to the lungs, liver and lymph nodes, and a solitary osteolytic bone metastasis seen in bone scan. It is well known that osseous metastasis from prostate cancer is primarily sclerotic, although lytic bone metastasis is rare, but it can also be seen as in our case.
基金supported by the National Natural Science Foundation of China(No.82202450).
文摘Large bone defects in load-bearing bone can result from tumor resection,osteomyelitis,trauma,and other factors.Although bone has the intrinsic potential to self-repair and regenerate,the repair of large bone defects which exceed a certain critical size remains a substantial clinical challenge.Traditionally,repair methods involve using autologous or allogeneic bone tissue to replace the lost bone tissue at defect sites,and autogenous bone grafting remains the“gold standard”treatment.However,the application of traditional bone grafts is limited by drawbacks such as the quantity of extractable bone,donor-site morbidities,and the risk of rejection.In recent years,the clinical demand for alternatives to traditional bone grafts has promoted the development of novel bone-grafting substitutes.In addition to osteoconductivity and osteoinductivity,optimal mechanical properties have recently been the focus of efforts to improve the treatment success of novel bone-grafting alternatives in load-bearing bone defects,but most biomaterial synthetic scaffolds cannot provide sufficient mechanical strength.A fundamental challenge is to find an appropriate balance between mechanical and tissue-regeneration requirements.In this review,the use of traditional bone grafts in load-bearing bone defects,as well as their advantages and disadvantages,is summarized and reviewed.Furthermore,we highlight recent development strategies for novel bone grafts appropriate for load-bearing bone defects based on substance,structural,and functional bionics to provide ideas and directions for future research.
文摘Maxillary bone loss impairs essential functions (chewing, swallowing, speech) and gives patients a very unaesthetic appearance due to the removal of facial support tissues, leading to serious psychological consequences. Treatment is multidisciplinary and requires a resective surgery if the cause is tumor-related, or an additive surgery if the cause is traumatic. This article aims to show the role of making a prosthesis to restore function (chewing, swallowing, speech) and aesthetics following maxillary bone loss. We will eighter present a clinical case involving a right maxillary tumor that was surgically resected followed by radiotherapy, and subsequently rehabilitated with a maxillofacial prosthesis in the consultation and dental treatment center of the university hospital center of Casablanca.
