BACKGROUND:Carnosic acid,a bioactive compound found in rosemary,has been shown to reduce inflammation and reactive oxygen species(ROS).However,its mechanism of action in osteoclast differentiation remains unclear. OBJECTIVE:To investigate the effects of carnosic acid on osteoclast activation,ROS production,and mitochondrial function. METHODS:Primary bone marrow-derived macrophages from mice were extracted and cultured in vitro.Different concentrations of carnosic acid(0,10,15,20,25 and 30 μmol/L)were tested for their effects on bone marrow-derived macrophage proliferation and toxicity using the cell counting kit-8 cell viability assay to determine a safe concentration.Bone marrow-derived macrophages were cultured in graded concentrations and induced by receptor activator of nuclear factor-κB ligand for osteoclast differentiation for 5-7 days.The effects of carnosic acid on osteoclast differentiation and function were then observed through tartrate-resistant acid phosphatase staining,F-actin staining,H2DCFDA probe and mitochondrial ROS,and Mito-Tracker fluorescence detection.Western blot and RT-PCR assays were subsequently conducted to examine the effects of carnosic acid on the upstream and downstream proteins of the receptor activator of nuclear factor-κB ligand-induced MAPK signaling pathway. RESULTS AND CONCLUSION:Tartrate-resistant acid phosphatase staining and F-actin staining showed that carnosic acid dose-dependently inhibited in vitro osteoclast differentiation and actin ring formation in the cell cytoskeleton,with the highest inhibitory effect observed in the high concentration group(30 μmol/L).Carnosic acid exhibited the most significant inhibitory effect during the early stages(days 1-3)of osteoclast differentiation compared to other intervention periods.Fluorescence imaging using the H2DCFDA probe,mitochondrial ROS,and Mito-Tracker demonstrated that carnosic acid inhibited cellular and mitochondrial ROS production while reducing mitochondrial membrane potential,thereby influencing mitochondrial function.The results of western blot and RT-PCR revealed that carnosic acid could suppress the expression of NFATc1,CTSK,MMP9,and C-fos proteins associated with osteoclast differentiation,and downregulate the expression of NFATc1,Atp6vod2,ACP5,CTSK,and C-fos genes related to osteoclast differentiation.Furthermore,carnosic acid enhanced the expression of antioxidant enzyme proteins and reduced the generation of ROS during the process of osteoclast differentiation.Overall,carnosic acid exerts its inhibitory effects on osteoclast differentiation by inhibiting the phosphorylation modification of the P38/ERK/JNK protein and activating the MAPK signaling pathway in bone marrow-derived macrophages.

BACKGROUND:Mesenchymal stem cells can regulate the tumor microenvironment by secreting extracellular vesicles containing cytokines,growth factors and exosomes for the precise regulation of biological behavior of tumor cells. OBJECTIVE:To investigate the effects of human umbilical cord-derived mesenchymal stem cell conditioned medium and their released exosomes on the biological properties of hepatocellular carcinoma cells. METHODS:Human umbilical cord mesenchymal stem cell supernatant was collected,centrifuged and filtered at high speed to obtain human umbilical cord mesenchymal stem cell conditioned medium.Human umbilical cord mesenchymal stem cell supernatant was collected and human umbilical cord mesenchymal stem cell exosomes were extracted by ultra-high speed gradient centrifugation.Human umbilical cord mesenchymal stem cell exosomes were labeled with PKH26 and co-cultured with hepatocellular carcinoma cell MHCC97-H.The uptake of exosomes by MHCC97-H cells was observed by fluorescence microscopy.The effects of human umbilical cord mesenchymal stem cell conditioned medium and human umbilical cord mesenchymal stem cell exosomes on biological functions of hepatocellular carcinoma cells were assessed by the CCK-8 proliferation assay,Transwell migration and invasion assay,and the apoptosis assay. RESULTS AND CONCLUSION:(1)Human umbilical cord mesenchymal stem cell exosomes could be uptaken by MHCC97-H cells and was mainly distributed in the cytoplasm.(2)After treatment with human umbilical cord mesenchymal stem cell conditioned medium,MHCC97-H cells showed a significant increase in proliferation,migration,and invasion(P<0.001,P<0.05,P<0.01),and a significant decrease in apoptosis(P<0.001),while after treatment with human umbilical cord mesenchymal stem cell exosomes,MHCC97-H cells showed a decrease in proliferation(P<0.001)and migration,invasion,and apoptosis were significantly enhanced(P<0.001).(3)The results indicated that human umbilical cord mesenchymal stem cell conditioned medium had the ability to promote the proliferation,migration,invasion,and inhibit apoptosis of MHCC97-H cells,while human umbilical cord mesenchymal stem cell exosomes had the properties of promoting the migration,invasion and apoptosis of MHCC97-H cells,inhibiting the proliferation.

BACKGROUND:Intertrochanteric fracture of femur has various fracture types and fixation methods,and the mechanical stability of each fixation system is quite different.It is of scientific clinical significance to use finite element analysis method to carry out biomechanical research on various fixation systems. OBJECTIVE:To compare and analyze the mechanical stability of various internal fixations applied to femoral intertrochanteric fracture A031-A2.1 by finite element method. METHODS:Based on the validated finite element model of femur(Intact),the model was cut and made into A031-A2.1 intertrochanteric fracture of femur.Different internal fixation systems were implanted by simulating clinical operation methods,and fixation models of proximal femoral nail antirotation,dynamic hip screw,percutaneous compression plate and proximal femoral locking plate were established respectively.All nodes under the distal femur of the four groups of models were constrained,and compression loads of 700,1 400 and 2 100 N were applied to the femoral head.Von Mises stress distribution and compression stiffness of each group of models were observed through calculation and analysis,and mechanical stability of each group was compared. RESULTS AND CONCLUSION:(1)Through calculation and analysis,after calculating the compression stiffness by comparing the deformation of each model,the compression stiffness of each model under various loads showed the trend:physiological group>proximal femoral nail antirotation group>proximal femoral locking plate group>percutaneous compression plate group>dynamic hip screw group.The compressive stiffness of the complete physiological group model was significantly higher than that of all surgical group models.(2)The stress index was observed.Due to the stress shielding effect,the stress peak value of each fixed group was higher than that of physiological group,and the maximum peak value was concentrated on each internal fixation.Proximal femoral nail antirotation group had the smallest stress peak,while dynamic hip screw group had the highest stress.The stress distribution trend showed physiological group

BACKGROUND:Osteoporotic vertebral fractures are the most common complication in patients with osteoporosis.As a new imaging technique,spine magnetic resonance imaging(MRI)is much more sensitive than X-ray film in the diagnosis of osteoporotic vertebral fractures.However,total spine MRI is costly and takes a long time to scan.Therefore,there is no consensus on whether all patients with osteoporotic vertebral fractures need to undergo total spine MRI scan and which patients need to undergo total spine MRI. OBJECTIVE:To analyze the distribution characteristics of vertebral fractures and explore their clinical significance by observing the whole spine MRI data of osteoporotic vertebral fractures patients. METHODS:Data of cases and MRI images of all patients diagnosed with fresh osteoporotic vertebral fractures who visited the Department of Orthopedics,Affiliated Hospital of Southwest Medical University from August 2018 to September 2022 were retrospectively analyzed.903 patients were included in the study based on inclusion and exclusion criteria.General information(age,gender,and body mass index),medical history characteristics(duration of illness,history of trauma surgery,percussion pain area,and pain score)were collected.The characteristics of vertebral fractures were analyzed through whole spine magnetic resonance imaging.Firstly,based on the number of vertebral fractures in patients,they were divided into the single vertebral fracture group(484 cases)and the multi-vertebral fracture group(419 cases),and the differences were analyzed between the two groups.Then,based on whether the farthest interval between the fractured vertebrae was greater than or equal to 5,the multi vertebral fracture group was further divided into two subgroups.Among them,Group A(the farthest interval between the fractured vertebrae was less than 5)contained 306 cases;Group B(with the farthest interval between fractured vertebral bodies greater than 5)included 113 cases.The differences were analyzed between two subgroups. RESULTS AND CONCLUSION:(1)Among 903 patients,419 patients(46.4%)had more than two fractured vertebrae.There were 654 patients(72.4%)with thoracolumbar fractures,and 54 patients(6%)with fractures in the thoracic plus lumbar region and the entire thoracic to lumbar region.In group B,96.5%of patients had multiregional percussion pain.(2)Compared with the patients in the single vertebral fracture group and the multi-vertebral fracture group,there were significant differences in bone mineral density,whether the medical history was greater than or equal to 1 month,the history of low energy injury,and the distribution and number of axial percussion pain areas in the spine during physical examination between the two groups(P<0.05).Age,gender,body mass index,whether there was underlying disease,pain visual analog scale score,whether there was a history of elderly thoracolumbar fracture,and whether there was a history of thoracolumbar surgery,and the number of fractured vertebrae had no statistical significance(P>0.05).(3)There were statistically significant differences between the Groups A and B in bone mineral density,the distribution and quantity of percussion pain area,and the history of low energy injury(P<0.05).There were no significant differences in age,gender,history of old fractures,visual analog scale score,body mass index,whether the medical history was longer than or equal to 1 month,history of underlying diseases,and history of thoracolumbar surgery between the two groups(P>0.05).(4)Patients with multiple low-energy trauma history,history of more than 1 month,multiple percussion pain,and the lower bone mineral density should be alert to the occurrence of multiple vertebral fracture and jump fracture.We recommend the whole spinal MRI for these patients.

BACKGROUND:The authors found that when the bilateral percutaneous vertebral augmentation is used to treat osteoporotic vertebral compression fractures with a total bone cement injection of 4 mL or more,different distribution patterns were usually presented on the X-rays;however,there were few reports addressing the effects of these patterns of bone cement distribution on the biomechanical properties of fractural vertebrae. OBJECTIVE:To further explore the biomechanical effects of different bone cement filling doses and distribution patterns on biomechanics of the fractural vertebrae using the finite element method. METHODS:The L1-L3 finite element models of osteoporosis were established,and the vertebral compression fractures were simulated in L2.Four distribution patterns bilateral partial fusion(FH type),full fusion(FO type),symmetrical separation(SA type),and asymmetric segregation(SN type)were simulated in 4 and 6 mL injections in the osteoporotic vertebral compression fracture models,respectively,and a total of nine sets of models were obtained.These models were solved under the same boundary conditions and compared with the stress and displacement of the L2 fractural vertebra. RESULTS AND CONCLUSION:(1)The maximum stresses of the nine groups of models were concentrated in the L2 fractural area,and the maximum stress and maximum displacement of each filling model were lower than in the osteoporotic vertebral compression fracture model,indicating the effectiveness of bone cement filling in the treatment of osteoporotic vertebral compression fracture.(2)Compared with 4 mL bone cement filling,6 mL bone cement filling could significantly reduce the stress of fractured vertebrae and enhance the strength of fractured vertebrae while improving the stability of fractured vertebrae.(3)In the same state of movement,the FH type stress was the least,followed by the SA type,both of which were close.FO type stress was the largest,especially in the lateral bend,which might be associated with its cluster shape resulting in the concentration of lateral stress.In the aspect of displacement,FH type was the least and FO type was the largest.(4)The results show that increased dose of bone cement injection reduces fractural vertebral stress and improves stability,but increases the risk of leakage.Bilateral symmetrical dispersed bone cement(FH type,SA type)is superior in restoring vertebral strength and stability than full fusion(FO type),asymmetric separated(SN type)bone cement.Therefore,when clinically performing bilateral percutaneous vertebral augmentation treatment of osteoporotic vertebral compression fractures,the bilateral symmetric dispersions of the distribution are first guaranteed;priority is recommended for FH type distribution,for appropriate stress stimulation and best stability.

Objective To analyze the application effects of artificial intelligence (AI) software and Mimics software in preoperative three-dimensional (3D) reconstruction for thoracoscopic anatomical pulmonary segmentectomy. Methods A retrospective analysis was conducted on patients who underwent thoracoscopic pulmonary segmentectomy at the Second People's Hospital of Huai'an from October 2019 to March 2024. Patients who underwent AI 3D reconstruction were included in the AI group, those who underwent Mimics 3D reconstruction were included in the Mimics group, and those who did not undergo 3D reconstruction were included in the control group. Perioperative related indicators of each group were compared. Results A total of 168 patients were included, including 73 males and 95 females, aged 25-81 (61.61±10.55) years. There were 79 patients in the AI group, 53 patients in the Mimics group, and 36 patients in the control group. There were no statistical differences in gender, age, smoking history, nodule size, number of lymph node dissection groups, postoperative pathological results, or postoperative complications among the three groups (P>0.05). There were statistical differences in operation time (P<0.001), extubation time (P<0.001), drainage volume (P<0.001), bleeding volume (P<0.001), and postoperative hospital stay (P=0.001) among the three groups. There were no statistical differences in operation time, extubation time, bleeding volume, or postoperative hospital stay between the AI group and the Mimics group (P>0.05). There was no statistical difference in drainage volume between the AI group and the control group (P=0.494), while there were statistical differences in operation time, drainage tube retention time, bleeding volume, and postoperative hospital stay (P<0.05). Conclusion For patients requiring thoracoscopic anatomical pulmonary segmentectomy, preoperative 3D reconstruction and preoperative planning based on 3D images can shorten the operation time, postoperative extubation time and hospital stay, and reduce intraoperative bleeding and postoperative drainage volume compared with reading CT images only. The use of AI software for 3D reconstruction is not inferior to Mimics manual 3D reconstruction in terms of surgical guidance and postoperative recovery, which can reduce the workload of clinicians and is worth promoting.

OBJECTIVE To investigate the ameliorative effect and potential mechanism of imperatorin （IMP） on doxorubicin （DOX） resistance in breast cancer. METHODS The effects of maximum non-toxic concentration （100 μg/mL） of IMP combined with different concentrations of DOX （12.5， 25， 50， 75， 100 μg/mL） on the proliferation of MCF-7/DOX cells were determined by MTT method. MCF-7/DOX cells were divided into blank control group （1‰ dimethyl sulfoxide）， DOX group （50 μg/mL）， IMP+DOX group （100 μg/mL IMP+50 μg/mL DOX） and IMP group （100 μg/mL）. mRNA and protein expressions of multidrug resistance protein 1 （MDR1） and multidrug resistance-associated protein 1 in each group were measured. The relevant pathways and targets involved in the improvement of DOX resistance in breast cancer cells by IMP were screened and validated by using transcriptome sequencing technology， along with gene ontology （GO） enrichment analyses and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment analyses. RESULTS Compared with DOX alone， the combination of IMP and DOX reduced the half inhibitory concentration of DOX on MCF-7/DOX cells from 81.965 μg/mL to 43.170 μg/mL， the reverse fold was 1.90， and the mRNA expression of MDR1 was significantly down-regulated （P＜0.05）. The results of GO enrichment analyses and KEGG pathway enrichment analyses indicated that the reversal of DOX resistance in breast cancer by IMP was mainly associated with the regulation of biological processes such as detoxification， multiple biological processes， and cell killing. The main pathway involved was the p53 signaling pathway， and the key targets mainly included constitutively photomorphogenic protein 1 （COP1）， cyclin E1 （CCNE1）， growth arrest and DNA damage-inducible protein 45A E-mail：tangxilan1983@163.com （GADD45A） and GADD45B. The results of the verification experiments showed that compared with DOX group， there was a trend of up-regulation of COP1 mRNA， and significant down- regulation of CCNE1， GADD45A， and GADD45B mRNA expression in IMP+DOX group （P＜0.05）. CONCLUSIONS The effect of IMP in ameliorating DOX resistance in breast cancer is related to its regulation of COP1， CCNE1， GADD45A and GADD45B targets in the p53 signaling pathway.

Objective: Miniscrews are commonly utilized as temporary anchorage devices (TADs) in cases of maxillary protrusion and premolar extraction. This study aimed to investigate the effects and potential side effects of two conventional miniscrew configurations on the maxillary incisors. Methods: Eighty-two adult patients with maxillary dentoalveolar protrusion who had undergone bilateral first premolar extraction were retrospectively divided into three groups: non-TAD, two posterior miniscrews only (P-TADs), and two anterior and two posterior miniscrews combined (AP-TADs). Cone-beam computed tomography was used to evaluate the maxillary central incisors (U1). Results: The APTADs group had significantly greater U1 intrusion (1.99 ± 2.37 mm, n = 50) and less retroclination (1.70° ± 8.80°) compared to the P-TADs (–0.07 ± 1.65 mm and 9.45° ± 10.68°, n = 60) and non-TAD group (0.30 ± 1.61 mm and 1.91° ± 9.39°, n = 54).However, the AP-TADs group suffered from significantly greater apical root resorption (ARR) of U1 (2.69 ± 1.38 mm) than the P-TADs (1.63 ± 1.46 mm) and non-TAD group (0.89 ± 0.97 mm). Notably, the incidence of grade IV ARR was 16.6% in the AP-TADs group, significantly higher than the rates observed in the P-TADs (6.7%) and non-TAD (1.9%) groups. Multiple regression analysis revealed that after excluding tooth movement factors, the AP-TADs configuration resulted in an additional 0.5 mm of ARR compared with the P-TADs group. Conclusions In cases of maxillary protrusion and premolar extraction, the use of combined anterior and posterior miniscrews enhances incisor intrusion and minimizes torque loss of the maxillary incisors. However, this approach results in more severe ARR, likely due to the increased apical movement and composite force exerted.

“Runner’s high” refers to a momentary sense of pleasure that suddenly appears during running or other exercise activities, characterized by anti-anxiety, pain relief, and other symptoms. The neurobiological mechanism of “runner’s high” is unclear. This review summarizes human and animal models for studying “runner’s high”, analyzes the neurotransmitters and neural circuits involved in runner’s high, and elucidates the evidence and shortcomings of researches related to “runner’s high”. This review also provides prospects for future research. Research has found that exercise lasting more than 30 min and with an intensity exceeding 70% of the maximum heart rate can reach a “runner’s high”. Human experiments on “runner’s high” mostly use treadmill exercise intervention, and evaluate it through questionnaire surveys, measurement of plasma AEA, miRNA and other indicators. Animal experiments often use voluntary wheel running intervention, and evaluate it through behavioral experiments such as conditional place preference, light dark box experiments (anxiety), hot plate experiments (pain sensitivity), and measurement of plasma AEA and other indicators. Dopamine, endogenous opioid peptides, endogenous cannabinoids, brain-derived neurotrophic factor, and other substances increase after exercise, which may be related to the “runner’s high”. However, attention should be paid to the functional differences of these substances in the central and peripheral regions, as well as in different brain regions. Moreover, current studies have not identified the targets of the neurotransmitters or neural factors mentioned above, and further in-depth researches are needed. The mesolimbic dopamine system, prefrontal cortex-nucleus accumbens projection, ventral hippocampus-nucleus accumbens projection, red nucleus-ventral tegmental area projection, cerebellar-ventral tegmental area projection, and brain-gut axis may be involved in the regulation of runner’s high, but there is a lack of direct evidence to prove their involvement. There are still many issues that need to be addressed in the research on the neurobiological mechanisms of “runner’s high”. (1) Most studies on “runner’s high” involve one-time exercise, and the characteristics of changes in “runner’s high” during long-term exercise still need to be explored. (2) The using of scales to evaluate subjects lead to the lacking of objective indicators. However, some potential biomarkers (such as endocannabinoids) have inconsistent characteristics of changes after one-time and long-term exercise. (3) The neurotransmitters involved in the formation of the “runner’s high” all increase in the peripheral and/or central nervous system after exercise. Attention should be paid to whether peripheral substances can enter the blood-brain barrier and the binding effects of neurotransmitters to different receptors are completely different in different brain regions. (4) Most of the current evidence show that some brain regions are activated after exercise. Is there a functional circuit mediating “runner’s high” between these brain regions? (5) Although training at a specific exercise intensity can lead to “runner’s high”, most runners have not experienced “runner’s high”. Can more scientific training methods or technological means be used to make it easier for people to experience the “runner’s high” and thus be more willing to engage in exercise? (6) The “runner’s high” and “addiction” behaviors are extremely similar, and there are evidences that exercise can reverse addictive behaviors. However, why is there still a considerable number of people in the sports population and even athletes who smoke or use addictive drugs instead of pursuing the “pleasure” brought by exercise? Solving the problems above is of great significance for enhancing the desire of exercise, improving the clinical application of neurological and psychiatric diseases through exercise, and enhancing the overall physical fitness of the population.

ObjectiveTo observe the prevention and control effect of processed Polygonatum cyrtonema on depression induced by chronic unpredictable mild stress （CUMS） in female rats. MethodsForty rats were assigned into control， model， and low-， medium-， and high-dose processed P. cyrtonema groups according to the random number table method， with 8 rats in each group. The rat model of depression was established with the CUMS method. The body mass， open field test， forced swimming test， Morris water maze test， levels of neurotransmitters ［dopamine （DA）， 5-hydroxytryptamine （5-TH）， and acetylcholine （ACh）］， serum levels of sex hormones ［gonadotropin-releasing hormone（GnRH）， testosterone （T）， and estradiol （E₂）］ and inflammatory factors ［tumor necrosis factor-α （TNF-α）， interleukin （IL）-6， and IL-10］， and mRNA and protein levels of factors in the brain-derived neurotrophic factor （BDNF）/tyrosine kinase receptor B （TRKB）/cAMP-response element binding protein （CREB） pathway were employed to evaluate the effect of processed P. cyrtonema on the CUMS-induced depression in female rats. ResultsThe body mass， open field test results， and forced swimming test results showed that the rat model of depression was successfully established. The comparison of behaviors， neurotransmitters， sex hormones， inflammatory factors， and neural pathways among groups showed that processed P. cyrtonema had different effects of preventing the development of depression in female rats. SPSS 25 was used for statistical analysis of error and significance. T test was conducted between groups. Each treatment group showed significant therapeutic effect compared with the model group （P<0.05）. Processed P. cyrtonema elevated the level of 5-TH （P<0.01） and lowered the levels of DA and ACh （P<0.01） in the brain tissue of female rats. In addition， it reduced the serum levels of GnRH， T， E₂， TNF-α， and IL-6 （P<0.05） and up-regulated the mRNA levels of BDNF and TRKB in the rat brain. ConclusionProcessed P. cyrtonema has a non-hyperactive preventive effect on CUMS-induced depression in rats， which provides a theoretical basis for the development of processed P. cyrtonema as a functional food product.