BACKGROUND:Bone marrow mesenchymal stem cells play a crucial role in treatment of diseases,such as femoral head necrosis,and the therapeutic efficacy is closely related to the quality of the cells.The empowerment of cells has become a research focus.OBJECTIVE:To investigate the effects of hypoxia mimetic dimethylglyoxal glycine pretreatment on mitophagy and differentiation capacity of human bone marrow mesenchymal stem cells.METHODS:Bone marrow mesenchymal stem cells were extracted from the bone marrow of patients' iliac crest and cultured in vitro to the third passage.The cells were treated with dimethylglyoxal glycine at 0,10,50,and 100 μmol/Lfor 24 hours,followed by the replacement with an osteogenic induction differentiation medium,which constituted the pretreatment group.The continuous treatment group was cultured directly in osteogenic induction medium containing 0,10,50,and 100 μmol/L dimethylglyoxal glycine after cell adhesion.After 7 days of induction,alkaline phosphatase staining was performed to select the most favorable conditions for osteogenic differentiation for subsequent experiments,with normally cultured bone marrow mesenchymal stem cells serving as the control group.Alkaline phosphatase staining,alkaline phosphatase activity,oil red O staining,and related RT-qPCR were used to evaluate the osteogenic and adipogenic differentiation differences of bone marrow mesenchymal stem cells between the two groups.MitoSox staining was used to detect mitochondrial reactive oxygen species levels.Mito-tracker and Lyso-tracker staining were used to detect the co-localization of mitochondria and lysosomes.The fluorescent probe JC-1 was used to measure mitochondrial membrane potential.RESULTS AND CONCLUSION:Alkaline phosphatase staining indicated that the most beneficial treatment for bone marrow mesenchymal stem cell osteogenesis was pretreatment with 10 μmol/L dimethylglyoxal glycine for 24 hours.Compared with the control group,the experimental group showed enhanced alkaline phosphatase staining expression,increased alkaline phosphatase activity and osteogenic gene expression,reduced lipid droplet formation and adipogenic gene expression as indicated by oil red O staining,decreased mitochondrial reactive oxygen species production,increased co-localization of mitochondria and lysosomes,and elevated mitochondrial membrane potential.The results suggest that 10 μmol/L dimethylglyoxal glycine pretreatment can promote osteogenic differentiation of bone marrow mesenchymal stem cells,inhibit adipogenic differentiation,and enhance mitophagy.

BACKGROUND:The mesenchymal stem cell secretome contains bioactive substances,cytokines,and growth factors.Three-dimensional cell culture can regulate the secretion of these components,potentially enhancing the ability to promote injury repair.OBJECTIVE:To investigate the repair effect of three-dimensional cultured human umbilical cord mesenchymal stem cell secretome on skin injuries in mice.METHODS:Human umbilical cord mesenchymal stem cells were cultured in conventional two-dimensional culture dishes and 96-well U-bottom cell culture plates,from which their secretory components were subsequently collected.The expression of skin damage repair related secretory factors in umbilical cord mesenchymal stem cells was analyzed using RT-qPCR.The protein expression level of skin damage repair related factors in umbilical cord mesenchymal stem cell secretome was detected using enzyme-linked immunosorbent assay.The potential of human umbilical cord mesenchymal stem cell secretome to repair vascular injuries was evaluated using an immortalized human umbilical vein endothelial cell migration model.A mouse skin injury model was established,and the human umbilical cord mesenchymal stem cell secretome was injected subcutaneously.Repair effects on skin injury were assessed through wound healing rates and histopathological analysis.RESULTS AND CONCLUSION:(1)After three days of cultivation,human umbilical cord mesenchymal stem cells cultured in two dimensions exhibited a fibroblast-like,swirling growth pattern,whereas three-dimensional culture led to the formation of uniform microspheres.(2)Compared with two-dimensional culture,three-dimensional culture significantly increased the mRNA expression of transforming growth factor β and basic fibroblast growth factor in human umbilical cord mesenchymal stem cells.(3)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly enhanced the protein expression of vascular endothelial growth factor,interleukin-10,and granulocyte-macrophage colony-stimulating factor in the human umbilical cord mesenchymal stem cell secretome.(4)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly promoted the migration of immortalized human umbilical cord mesenchymal stem cells.(5)Compared with the untreated control group and the two-dimensional cultured human umbilical cord mesenchymal stem cell secretome,the three-dimensional cultured human umbilical cord mesenchymal stem cell secretome can significantly accelerate the skin wound healing rate and wound skin structure remodeling in mice.These results indicate that three-dimensional culture can enhance the expression of paracrine factors of human umbilical cord mesenchymal stem cells,and their secretome can significantly promote the repair of mouse skin damage.

OBJECTIVE:Elevated blood pressure increases the risk of cardiovascular diseases.Isometric exercise training has been shown to significantly reduce resting blood pressure,but the factors influencing its effectiveness remain unclear,and specific application guidelines are yet to be established.This study aims to evaluate the impact of isometric exercise training on resting blood pressure through meta-analysis,explore its moderating factors,and provide evidence-based recommendations based on its dose-response relationship.METHODS:Following the PRISMA guidelines,a systematic search was conducted in PubMed,Embase,Cochrane Library,Scopus,and Web of Science databases using keywords"Isometric exercise training,""Systolic blood pressure,"and"Diastolic blood pressure,"covering literature up to September 2024.Randomized controlled trials involving isometric exercise training and resting blood pressure were included.Three independent researchers performed literature screening and data extraction,assessing bias risk and quality grades using the Risk of Bias 2.0 tool and GRADE framework.Main effect pooling,publication bias assessment,subgroup,and regression analysis were conducted using R software(version 4.3.4).RESULTS:A total of 28 articles(comprising 32 randomized controlled trials)involving 977 participants were included.(1)Meta-analysis results indicated that isometric exercise training significantly reduced resting systolic blood pressure(MD=-8.01,95％CI=-9.22 to-6.80,P＜0.01,I2=18.20％,low evidence grade)and diastolic blood pressure(MD=-3.46,95％CI=-4.64 to-2.28,P＜0.01,I2=0％,moderate evidence grade)compared to no exercise.(2)Subgroup analysis results revealed significant influences of gender,health status,exercise modality,frequency,intensity,duration,sets per session,rest duration,and baseline blood pressure on the main effects for both systolic(P＜0.01)and diastolic blood pressure(P＜0.05).(3)Regression analysis results did not show any significant influencing factors,but body mass index(β=-4.11,P=0.091)showed a significant negative trend on the main effect for systolic blood pressure.(4)No significant publication bias was observed in the meta-analysis results(P＞0.05).CONCLUSION:(1)Isometric exercise training significantly lowers systolic(low evidence grade)and diastolic(moderate evidence grade)blood pressure with clinically meaningful thresholds.(2)Participant characteristics(gender,health status,baseline blood pressure,and body mass index)and isometric exercise training protocols(modality,frequency,intensity,duration,cycle,sets per session,and rest duration)influence its antihypertensive effects.(3)The article recommends the optimal blood pressure management prescription:three sessions per week,with four sets per session,each set lasting 2 minutes with a 2-minute rest,at an intensity of 95％HRpeak using isometric wall squat exercises;the intervention period can be adjusted around a 6-week node.Future high-quality research is urgently needed to further validate and support these conclusions.

BACKGROUND:Novel biomaterials not only provide the necessary mechanical support but also promote cell proliferation and differentiation,inducing bone regeneration,thereby improving therapeutic outcomes and offering new perspectives and methods for the development of bone regenerative technologies.OBJECTIVE:To visualize the research status and development prospects of biomaterials in the field of bone regeneration through bibliometric methods.METHODS:A total of 500 of the most influential papers on bone regeneration and biomaterials were selected from the Web of Science Core Collection database from inception to September 24,2024.VOSviewer and CiteSpace tools were used for in-depth bibliometric visualization analysis to reveal the research trends and core literature in this field.RESULTS AND CONCLUSION:Among the selected 500 papers,China and the United States were in a leading position in terms of the number of published papers and citation rates,with ChangJiang being the most prolific author and the journal Acta Biomaterialia publishing the most articles.Bone regeneration and material science is an interdisciplinary research field,covering various disciplines including materials science,biomedical engineering,cell biology,and molecular biology.Research on bone repair materials is shifting from traditional bioinert materials to bioactive materials,which not only provide mechanical support but also promote cell proliferation and differentiation,inducing bone regeneration.Synthetic bone repair materials are gradually replacing traditional materials,becoming the preferred choice for clinical bone graft surgery due to their abundant sources,adjustable physicochemical properties,and lower risks of immune rejection and disease transmission.Researchers are continuously improving the biocompatibility,biomimetic properties,osteoconductivity,and osteoinductivity of these materials to make them closer to natural bone.The frontiers are mainly focused on bioactive ceramics,3D printing,hydrogels,chitosan,hydroxyapatite,and other materials.New materials play a vital role in the field of bone regeneration.With the continuous advancement of materials science and technology,the application prospects of these new materials in the field of bone regeneration are very broad,and they are expected to provide more effective and personalized treatment options for bone defect treatment.

BACKGROUND:Studies have confirmed that Pterocarya hupehensis skan total flavonoids(PHSTF)can improve the level of collagen-induced arthritis in rats,but there is still a lack of research on the regulation of Wnt/β-catenin signaling pathway in fibroblast-like synoviocytes and its effect on related cell functions.OBJECTIVE:To investigate the effect and mechanism of PHSTF on lipopolysaccharide-induced proliferation,migration and apoptosis of fibroblast-like synoviocytes based on the Wnt/β-catenin signaling pathwayMETHODS:Fibroblast-like synoviocytes were divided into control group,lipopolysaccharide group,lipopolysaccharide+low-,medium-,and high-dose PHSTF groups(10,20,and 40 μg/mL),lipopolysaccharide+Wnt pathway inhibitor DKK1 group,and lipopolysaccharide+Wnt pathway inhibitor DKK1+high-dose PHSTF group(40 μg/mL).The cell counting kit-8 method was used to detect the effect of PHSTF on the viability of fibroblast-like synoviocytes,and the final drug concentration and time were screened.Flow cytometry was used to detect the apoptosis of fibroblast-like synoviocytes.Cell scratch assay,EDU staining and cell cloning assay were used to detect the migration and proliferation of fibroblast-like synoviocytes.Western blot assay was used to detect the protein expression levels of Wnt3a,β-catenin,tumorigenic genes,matrix metalloproteinase 2,matrix metalloproteinase 9,Bax and Bcl-2 in fibroblast-like synoviocytes.RESULTS AND CONCLUSION:(1)Compared with the control group,the cell viability decreased significantly when the concentration of PHSTF was＞40 μg/mL(P＜0.01).Therefore,the drug concentration of≤40 μg/mL was selected for subsequent experiments.(2)Compared with the lipopolysaccharide group,the wound healing rate,cell clone formation rate and the number of EDU-positive cells in the low-,medium-and high-dose PHSTF groups were significantly reduced,while the apoptosis rate was significantly increased(P＜0.05-0.01).(3)Western blot results showed that compared with the lipopolysaccharide group,low-,medium-and high-dose PHSTF significantly inhibited cellular Wnt3a,β-catenin,cellular tumorigenic genes,matrix metalloproteinase 2,matrix metalloproteinase 9,and Bcl-2 protein expression,and promoted the expression of Bax protein(P＜0.01).(4)Compared with the DKK1 group,the combination of DKK1 and high-dose PHSTF significantly inhibited the protein expression of Wnt3a,β-catenin,matrix metalloproteinase 2,matrix metalloproteinase 9 and Bcl-2 protein expression and promoted the protein expression of Bax(P＜0.01).To conclude,PHSTF may inhibit the proliferation and migration of fibroblast-like synoviocytes and promote apoptosis by inhibiting the Wnt/β-catenin signaling pathway.

BACKGROUND:Fracture healing is a very complex physiological process,which is influenced by many factors.In recent years,the use of biomechanical factors in fracture healing has been a major focus in the field of orthopedics,and the mechanical stress environment around the fracture end has an important role in regulating fracture healing.Among them,the study of the mechanism of compressive mechanics on the cytokines of fracture ends is a hot spot for bone-related researchers.OBJECTIVE:To summarize the current status and recent advances in the study of the mechanism of action of compressive stress on cytokines in fracture healing in recent years.METHODS:A search with the keywords of"compressive stress,fracture healing,cytokine,bone morphogenetic protein,fibroblast growth factor,platelet-derived growth factor,vascular endothelial growth factor,interleukin,tumor necrosis factor-α"in Chinese and English was conducted in the CNKI,WanFang,PubMed,and Web of Science.Initially 506 articles were retrieved,and 94 eligible articles that met the criteria were screened and finally summarized.RESULTS AND CONCLUSION:Current studies have found that compressive stress has different effects on different cytokines during fracture healing,which can be achieved mainly by influencing cell signaling,gene expression regulation,and modulation of cell behavior.Among them,compressive stress can be linked to cytokines such as bone morphogenetic protein,fibroblast growth factor,platelet-derived growth factor,vascular endothelial growth factor,interleukin,and tumor necrosis factor-α.This process involves cell proliferation,differentiation and migration,inflammatory response,and changes in the environmental and nutritional conditions of the fracture end,which are key factors affecting fracture healing.The whole paper summarizes the complexity of cytokine action mechanism,the mechanism of compressive stress on its regulation needs to be further carried out in-depth research,and the problems and limitations in the research are considered and future prospects.

BACKGROUND:Age-related macular degeneration and deep vein thrombosis may share common pathophysiological mechanisms,but there is a lack of direct evidence regarding their relationship.Traditional studies are confounded by confounding factors and reverse causation.OBJECTIVE:To investigate the causal relationship between age-related macular degeneration and deep vein thrombosis based on Mendelian randomization design.METHODS:Through a two-way Mendelian randomization analysis,single nucleotide polymorphisms of exposure and outcomes were obtained from publicly available genome-wide association studies,with deep vein thrombosis data from the FinnGen database in a European population with a sample size of 363 612 and 1 048 575 single nucleotide polymorphisms.In addition,we obtained data on age-related macular degeneration from the IEUOpenGWAS project,also from a European population sample of 105 248 cases covering 11 304 110 single nucleotide polymorphisms.In R4.4.1,we used the TwoSampleMR package(version 0.6.8)to explore the causal effects of exposure factors on outcomes.At the same time,we also conducted a sensitivity analysis via MR-Egger regression,weighted median,weighted model and simple model methods to ensure that the assessment results were robust and reliable.In addition,we used the"heterogeneity"function to test for heterogeneity,and the"horizontal pleiotropy"function and the MR-PRESSO test to further assess horizontal pleotropy.The Cochran's Q test was used to determine whether there was statistical heterogeneity between single nucleotide polymorphisms,and the leave-one-out method was used to assess whether single nucleotide polymorphisms would significantly interfere with Mendelian randomization analysis.Funnel plots were drawn to assess the potential bias of single nucleotide polymorphisms.Forest plots were plotted to show the effect estimates of single nucleotide polymorphisms on exposure and outcomes,and their confidence intervals were plotted.Scatter plots were plotted to evaluate the relationship between the potency of single nucleotide polymorphisms and their causal effect size on outcome estimates.RESULTS AND CONCLUSION:Both forward and reverse studies showed that there was no causal association between age-related macular degeneration and the occurrence of deep vein thrombosis(P＞0.05).Sensitivity analysis showed that the main analysis results were reliable and robust,with no outliers,heterogeneity,and horizontal pleiotropy,and no single nucleotide polymorphism significantly affected the overall effect estimate.Although it is based on European population data,it has methodological reference value for Chinese biomedical research on complex disease associations.In this field,China can carry out multi-center large-sample studies,accurately analyze the internal links between Chinese population-related diseases,and provide a basis for prevention and treatment strategies and clinical practice.

BACKGROUND:Upper lumbar spinal stenosis is a multifactorial degenerative disorder of the spine.For narrowing of the spinal canal in the upper lumbar region(L1-L4),surgical decision-making is particularly complex.Existing minimally invasive surgeries each have their own advantages and limitations.Currently,there are few reports on biomechanical comparison and finite element analysis of different surgical methods for the treatment of high lumbar spinal stenosis.OBJECTIVE:To analyze the biomechanical impact of endoscopic unilateral laminotomy for bilateral decompression,transforaminal endoscopic lumbar decompression,and cross-overtop decompression in the treatment of upper lumbar spinal stenosis using endoscopy,and to verify the reliability and effectiveness of these three surgical techniques in treating upper lumbar spinal stenosis,providing a biomechanical basis for clinical decision-making.METHODS:The CT images of the lumbar spine of a healthy volunteer were selected,and the finite element model M0 of the normal lumbar L1-L5 segments was established using Mimics,Geomagic,Solid works,and Ansys software.The L2-L3 segment,representing upper lumbar characteristics,was chosen.Based on this model,the surgical models for endoscopic unilateral laminotomy for bilateral decompression(M1),transforaminal endoscopic lumbar decompression(M2),and cross-overtop decompression(M3)were established.Using software,the changes in the range of motion of the entire lumbar segment and the maximum Von Mises stress of the intervertebral discs were simulated and evaluated for each group of models under six loading conditions:flexion,extension,left lateral bending,right lateral bending,left rotation,and right rotation.RESULTS AND CONCLUSION:(1)Compared with model MO,the range of motion in M1,M2,and M3 increased under all six conditions,with M1 showing a greater increase.(2)M1 and M2 demonstrated significant increases in range of motion under forward bending,extension,and right rotation,while the increase under other conditions remained below 7％.(3)Compared with model M3,model M1 exhibited slightly increased overall joint range of motion during extension and left bending,while no significant changes were observed in other aspects,and the L1-L5 lumbar segments did not reach an unstable state.(4)In model M1,the maximum Von Mises stress of the intervertebral discs increased most significantly under flexion and extension loading conditions.However,under left lateral bending,right lateral bending,left rotation,and right rotation loading conditions,the increase did not exceed 5％.(5)These findings suggest that due to the sagittal anatomical characteristics of the facet joints,the unilateral laminotomy for bilateral decompression technique,while decompressing,involves resection of more facet joints,which impacts overall segmental stability.The transforaminal endoscopic lumbar decompression technique is suitable for patients with foraminal stenosis but cannot achieve complete decompression for those with severe ventral central stenosis.The Cross-Overtop technique effectively enlarges the volume of the central canal and lateral recess,optimizing decompression,and shows unique advantages in treating upper lumbar spinal stenosis.

BACKGROUND:Stress-induced damage to hippocampal neurons may underlie abnormalities in neuronal structure and function,ultimately leading to mood disorders.G protein-coupled receptors in brain tissue play an important role in mood regulation.OBJECTIVE:To analyze the mechanism of depression-like behavior in chronic social defeat stress mice based on high-throughput sequencing and bioinformatics analysis.METHODS:C57BL/6J mice were randomly divided into control group and model group.There was no special treatment in the control group,while a mouse model of chronic social defeat stress was established in the model group.Depression-like behavior was assessed through the sucrose preference test,tail suspension test,and forced swim test.Anxiety behavior was evaluated using the elevated plus-maze,while social behavior was measured through the social interaction test.Cognitive function was assessed with the Y-maze spontaneous alternation test.Immunofluorescence staining was performed to quantify microglia markers in the mouse hippocampus,and Nissl staining was used to examine neuronal damage in mice.High-throughput sequencing was used to identify differentially expressed genes and gene enrichment in the mouse hippocampus,and qPCR was used to measure the expression of G protein-coupled receptors in the mouse hippocampus.RESULTS AND CONCLUSION:(1)Compared with the control group,chronic social defeat stress mice showed significant behavioral impairments,including increased anxiety,depression,and cognitive deficits.(2)Additionally,the Nissl body light density in hippocampal neurons was significantly reduced in chronic social defeat stress mice.(3)Sequencing results revealed synaptic damage in the neurons after chronic social defeat stress.Microglia activation was also markedly increased in the hippocampus of CSDS mice.Furthermore,the expression of G protein-coupled receptors in the hippocampus was significantly higher in chronic social defeat stress mice compared with the control group.These findings suggest that chronic social defeat stress induces anxiety,depression,and cognitive deficits in mice,accompanied by neuropathological changes in the hippocampus,and that altered G protein-coupled receptors expression may play a key role in these behavioral and neuropathological changes.

OBJECTIVE:Some studies have shown that physical exercise can effectively improve knee extensor strength and cardiorespiratory function in burn patients;some studies have also shown that physical exercise is not effective in improving respiratory function in burn patients.Improvement effects of physical exercise on physical functions(muscle function,walking function,cardiopulmonary function,and lean body mass)of burn patients were evaluated by a systematic evaluation and meta-analysis.METHODS:Based on databases including Web of Science,PubMed,Embase,Cochrane Library,CNKI,WanFang,and the Chinese Biomedical Database,literature on the improvement of physical function in burn patients through physical exercise was searched using subject headings and free terms.With muscle function,walking ability,cardiopulmonary function,and lean body mass as the primary outcome measures,a meta-analysis was conducted to compare the efficacy of physical exercise with traditional physical therapy or conventional care methods.RESULTS:A total of 38 papers were included,of which 26 papers were included in the meta-analysis,involving 1 658 patients.Meta-analysis results showed that:(1)Physical exercise significantly enhances the knee extensor strength of the dominant leg in burn patients(mean difference[MD]=8.34,95％confidence interval[CI]:6.95-9.72,P＜0.000 01),increases quadriceps strength,peak oxygen uptake,forced vital capacity and maximum ventilation volume in 1 second,and resting heart rate(standardized mean difference[SMD]=4.41,95％CI:2.52-6.30,P＜0.000 01;MD=4.91,95％CI:3.52-6.29,P＜0.000 01;MD=5.86,95％CI:0.09-11.63,P=0.05;MD=6.90,95％CI:2.93-10.87,P=0.000 7;MD=5.03,95％CI:1.45-8.61,P=0.006),and improves the 6-minute walking distance,gait parameters,and total lean body mass(MD=45.29,95％CI:24.7-65.89,P＜0.0001;SMD=7.84,95％CI:6.05-9.63,P＜0.000 01;MD=2.47,95％CI:2.01-2.93,P＜0.000 01).(2)The subgroup analysis results indicated that the improvement in knee extensor strength of the dominant leg may be better in children than in adults and better in the extra-heavy group than in the heavy group.Improvement in the 6-minute walking distance is better in children than in adults,and higher degree of burn indicates better improvement effects,with no difference from the control group for＜12 weeks.Peak oxygen uptake may be better in adults and severe burn groups than in children and moderate burn groups,resistance combined with aerobic exercise modalities may be better than aerobic exercise alone,and exercise duration＞60 minutes may be better than＜60 minutes.CONCLUSION:Physical activity is effective in improving physical function in burn patients,as evidenced by improvements in muscle strength,walking ability,cardiorespiratory fitness,and lean body mass.The quality of evidence recommended for all indicator results is moderate or below,with imprecision and inconsistency being the main factors for downgrading.Therefore,more high-quality randomized controlled trials are needed in the future to verify the reliability of the results.