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: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.

OBJECTIVE To investigate the mechanism of Xibining Ⅱ formula in alleviating synovial inflammation and fibrosis in knee osteoarthritis （KOA） rats based on Janus kinase 2 （JAK2）/signal transducer and activator of transcription 3 （STAT3） pathway. METHODS Seventy-five male SD rats were randomly divided into sham operation group （Sham group）， KOA group， Xibining Ⅱ low-dose group （XBNⅡ-L group， 4 g/kg）， Xibining Ⅱ high-dose group （XBNⅡ-H group， 8 g/kg）， and Xibining Ⅱ high-dose combined with STAT3 activator Colivelin trifluoroacetate （C-TFA） group [C-TFA group， 8 g/kg Xibining Ⅱ+ 1.0 mg/（kg·d） C-TFA]， with 15 rats in each group. Except for the Sham group， the KOA model was established by anterior cruciate ligament transection in the other groups. After successful modeling， each group was given corresponding drugs by intragastric administration and （or） intraperitoneal injection once daily for 28 consecutive days. After the last medication， the pathological changes of synovial tissue of knee joint in each group were evaluated and the indicators were calculated. The levels of serum inflammatory factors were detected. The positive expressions of phosphorylated JAK2 （p-JAK2） and phosphorylated STAT3 （p-STAT3） in synovial tissue of the knee joint were detected. The expressions of JAK2/STAT3 pathway-related proteins and mRNAs in synovial tissue were detected. RESULTS Compared with the Sham group， the synovial lining cells in the KOA group showed significant proliferation and disordered arrangement； the Krenn score， fibrosis ratio， positive area percentage of p-JAK2 and p-STAT3， p-JAK2/JAK2 and p-STAT3/STAT3， protein expression of Collagen-Ⅰ and α -smooth muscle actin， the mRNA expression of JAK2， STAT3， Collagen-Ⅰ and α -smooth muscle actin， as well as serum levels of interleukin-1β and interleukin-18 were significantly increased （ P ＜0.05）. Compared with the KOA group， the above pathological changes were significantly improved in each dose group of Xibining Ⅱ formula， and all indicators were significantly decreased （ P ＜0.05）， with the XBNⅡ-H group showing better effects than the XBNⅡ-L group （ P ＜0.05）. Compared with the XBNⅡ-H group， the above pathological damages were aggravated in the C-TFA group， and all indicators were significantly worsened （ P ＜0.05）. CONCLUSIONS Xibining Ⅱ formula can alleviate synovial inflammation and fibrosis in KOA rats， and its mechanism may be related to inhibiting the activation of JAK2/STAT3 pathway.

ObjectiveTo establish and evaluate different disease-syndrome combination mice models of knee osteoarthritis （KOA） with cold-dampness obstruction syndrome， and to identify the optimal modeling method. MethodsEighty mice were randomly divided into a control group， a treadmill plus climate chamber group， an anterior cruciate ligament transection （ACLT） plus climate chamber group， an ACLT group， a destabilization of the medial meniscus （DMM） plus climate chamber group， a DMM group， an intra-articular injection plus climate chamber group， and an intra-articular injection group， with 10 mice in each group. Mice in the ACLT group underwent surgical transection of the knee anterior cruciate ligament to establish the model， while those in the DMM underwent surgical transection of the medial meniscal tibial ligament of the knee， and those in the intra-articular injection group were modeled by an intra-articular injection of 50 μl of normal saline containing 1mg of monosodium iodoacetate （MIA） into the medial side of the patellar ligament. Mice in the ACLT plus climate chamber， DMM plus climate chamber， and intra-articular injection plus climate chamber groups were placed in an artificial climate chamber （relative humidity 60%， temperature 4 ℃， wind speed 6 m/s） simultaneously with aforementioned interventions， once daily for 2 h each time， for 14 consecutive days. Mice in the control group underwent sham surgery， involving only the incision of the skin and subcutaneous tissue at the knee joint to expose the articular cavity， followed by layer-by-layer suturing. Mice in the treadmill plus climate chamber group were placed on an animal treadmill starting on the 4th day after the sham operation， undergoing high-intensity treadmill exercise at a speed of 20 m/min， an inclination of 5°， for 30min per session， 5 times per week for 28 consecutive days， while being housed in the artificial climate chamber. Cold pain thresholds of the mice in each group were compared using the cold plate test and the acetone low-temperature test before and after modeling. Following modeling， knee joint pathological changes were observed using HE and Safranin O-Fast Green staining， and quantified using Mankin and Osteoarthritis Research Society International （OARSI） scores. Serum levels of tumor necrosis factor-α （TNF-α） and interleukin-1β （IL-1β） were measured by ELISA. Protein and mRNA expression levels of pain-related markers， including calcitonin gene-related peptide （CGRP）， protein gene product 9.5 （PGP9.5）， and cellular proto-oncogene Fos （c-Fos）， and the cold hyperalgesia-related markers including transient receptor potential ankyrin 1 （TRPA1） and transient receptor potential melastatin 8 （TRPM8） in the dorsal root ganglion （DRG） tissues were detected by Western Blot and qPCR. TRPA1 and TRPM8 fluorescent intensity in the DRG was detected by immunofluorescence assay. ResultsCompared to the control group， the remaining groups showed decreased cold pain thresholds in the cold plate tese， increased cold pain thresholds in the acetone low-temperature test， elevated Mankin and OARSI scores， and increased serum TNF-α and IL-1β levels， upregulated protein and mRNA expression levels of CGRP， PGP9.5， c-Fos， TRPA1， and TRPM8 in the DRG， and increased immunofluorescence intensities of TRPA1 and TRPM8 in the DRG tissue （P＜0.05 or P＜0.01）， along with severe pathological damage and cartilage degeneration in the knee joints. Compared to the ACLT， DMM， and intra-articular injection groups， the ACLT plus climate chamber， DMM plus climate chamber， and intra-articular injection plus climate chamber groups exhibited more significant changes in all the aforementioned indicators （P＜0.01）. Furthermore， changes in the aforementioned indicators were more pronounced in the ACLT plus climate chamber group compared to the Treadmill plus climate chamber group， DMM plus climate chamber and intra-articular injection plus climate chamber group （P＜0.01）， exhibiting the most severe degree of pathological damage and cartilage degeneration. ConclusionThe combination of an artificial climate chamber can successfully establish a disease-syndrome combined animal model of KOA with cold-damp obstruction syndrome， with the ACLT combined with the artificial climate chamber being the optimal modeling approach.

ObjectiveTo establish and evaluate different disease-syndrome combination mice models of knee osteoarthritis （KOA） with cold-dampness obstruction syndrome， and to identify the optimal modeling method. MethodsEighty mice were randomly divided into a control group， a treadmill plus climate chamber group， an anterior cruciate ligament transection （ACLT） plus climate chamber group， an ACLT group， a destabilization of the medial meniscus （DMM） plus climate chamber group， a DMM group， an intra-articular injection plus climate chamber group， and an intra-articular injection group， with 10 mice in each group. Mice in the ACLT group underwent surgical transection of the knee anterior cruciate ligament to establish the model， while those in the DMM underwent surgical transection of the medial meniscal tibial ligament of the knee， and those in the intra-articular injection group were modeled by an intra-articular injection of 50 μl of normal saline containing 1mg of monosodium iodoacetate （MIA） into the medial side of the patellar ligament. Mice in the ACLT plus climate chamber， DMM plus climate chamber， and intra-articular injection plus climate chamber groups were placed in an artificial climate chamber （relative humidity 60%， temperature 4 ℃， wind speed 6 m/s） simultaneously with aforementioned interventions， once daily for 2 h each time， for 14 consecutive days. Mice in the control group underwent sham surgery， involving only the incision of the skin and subcutaneous tissue at the knee joint to expose the articular cavity， followed by layer-by-layer suturing. Mice in the treadmill plus climate chamber group were placed on an animal treadmill starting on the 4th day after the sham operation， undergoing high-intensity treadmill exercise at a speed of 20 m/min， an inclination of 5°， for 30min per session， 5 times per week for 28 consecutive days， while being housed in the artificial climate chamber. Cold pain thresholds of the mice in each group were compared using the cold plate test and the acetone low-temperature test before and after modeling. Following modeling， knee joint pathological changes were observed using HE and Safranin O-Fast Green staining， and quantified using Mankin and Osteoarthritis Research Society International （OARSI） scores. Serum levels of tumor necrosis factor-α （TNF-α） and interleukin-1β （IL-1β） were measured by ELISA. Protein and mRNA expression levels of pain-related markers， including calcitonin gene-related peptide （CGRP）， protein gene product 9.5 （PGP9.5）， and cellular proto-oncogene Fos （c-Fos）， and the cold hyperalgesia-related markers including transient receptor potential ankyrin 1 （TRPA1） and transient receptor potential melastatin 8 （TRPM8） in the dorsal root ganglion （DRG） tissues were detected by Western Blot and qPCR. TRPA1 and TRPM8 fluorescent intensity in the DRG was detected by immunofluorescence assay. ResultsCompared to the control group， the remaining groups showed decreased cold pain thresholds in the cold plate tese， increased cold pain thresholds in the acetone low-temperature test， elevated Mankin and OARSI scores， and increased serum TNF-α and IL-1β levels， upregulated protein and mRNA expression levels of CGRP， PGP9.5， c-Fos， TRPA1， and TRPM8 in the DRG， and increased immunofluorescence intensities of TRPA1 and TRPM8 in the DRG tissue （P＜0.05 or P＜0.01）， along with severe pathological damage and cartilage degeneration in the knee joints. Compared to the ACLT， DMM， and intra-articular injection groups， the ACLT plus climate chamber， DMM plus climate chamber， and intra-articular injection plus climate chamber groups exhibited more significant changes in all the aforementioned indicators （P＜0.01）. Furthermore， changes in the aforementioned indicators were more pronounced in the ACLT plus climate chamber group compared to the Treadmill plus climate chamber group， DMM plus climate chamber and intra-articular injection plus climate chamber group （P＜0.01）， exhibiting the most severe degree of pathological damage and cartilage degeneration. ConclusionThe combination of an artificial climate chamber can successfully establish a disease-syndrome combined animal model of KOA with cold-damp obstruction syndrome， with the ACLT combined with the artificial climate chamber being the optimal modeling approach.

Postmenopausal osteoporosis (PMOP), a bone metabolic imbalance disorder induced by estrogen deficiency, necessitates novel prevention and treatment strategies that transcend the constraints of conventional therapeutic approaches. Melatonin, a signaling molecule secreted by the pineal gland, plays a key role in maintaining circadian rhythms and regulating bone metabolism. In recent years, numerous studies both domestically and internationally have demonstrated that melatonin can promote the generation of osteoblasts and osteoclasts, thereby increasing bone density and improving symptoms of osteoporosis. This article reviews the role of melatonin in the prevention of PMOP, aiming to provide new ideas for the diagnosis and treatment of PMOP.

Objective:To analyze the carriage status, subtype distribution and flanking gene sequence characteristics of oxacillinases (OXA enzyme) in 241 clinical strains of Pseudomonas aeruginosa, and assess their roles in the drug resistance of Pseudomonas aeruginosa and ability to horizontally transfer across species. Methods:Clinical P. aeruginosa isolates were collected from four hospitals in Sanya, Tangshan, Zhangjiakou, and Beijing. The prevalence of oxacillinases and their flanking gene sequences was analyzed by whole-genome sequencing (NGS) and bioinformatic approaches. Results:A total of 241 isolates of P. aeruginosa were gathered, and 35 blaOXA subtypes were identified through screening of 252 blaOXA genes. These genes were classified into three subfamilies: blaOXA-50-like (241, 95.6%), blaOXA-1-like (9, 3.6%) and blaOXA-10-like (2, 0.8%). Among these, 11 subtypes (11, 31.4%) were novel blaOXA subtypes. Nine of these belonged to the blaOXA-50-like subfamily and were designated as blaOXA-1244, blaOXA-1245, blaOXA-1246, blaOXA-1250, blaOXA-1252, blaOXA-1253, blaOXA-1254, blaOXA-1255, and blaOXA-1256. The remaining two belonged to the blaOXA-10-like subfamily and were named blaOXA-1247 and blaOXA-1248. Compared to the amino acid sequence of OXA-10, the newly identified subtype OXA-1247 exhibited a mutation at position 117, where a valine was replaced by a leucine. This change was thought to improve the enzyme′s ability to hydrolyze carbapenems. In the analysis of the flanking sequences of the blaOXA genes, Class I integrons were identified in four bacterial strains. The variable regions of these integrons carried three distinct patterns of resistance gene cassettes: aac( 6′) -Ib-blaOXA-1247-ant( 3′′) -Ia, aac( 6′) -Ib-blaOXA-1248 and aac( 6′) -Ib- blaIMP-45-blaOXA-1-catB3. Among these, the strain BJ2326 carried a class I integron that was connected to the downstream IS CR1 element to form a composite class I integron structure, additionally carrying the resistance gene blaPER-1. Out of the 223 non-wild-type P. aeruginosa strains, 127 strains exhibited non-wild-type profiles to the four beta-lactam antibiotics MEM, CAZ, FEP, and TZP, with the combination of MEM+CAZ+FEP being the most prevalent, representing 57.0% of the total. Conclusions:The blaOXA genes in 241 clinical P. aeruginosa strains showed diversity. Some blaOXA genes had a co-transfer risk with the metallo-β-lactamase resistance gene blaIMP-45. Among the 11 newly discovered blaOXA subtypes, the new subtype OXA-1247 may have carbapenemase activity and potential for horizontal transfer.

Objective To observe the volume changes of brain regions and their correlation with cognitive function in temporal lobe epilepsy(TLE)patients.Methods Fifty TLE patients(TLE group)and 34 healthy controls(control group)were prospectively enrolled.Brain 3D-T1WI was collected,brain regions were delineated with automated segmentation technique,and hippocampus was segmented additionally with hippocampal brain template(HBT).The volume of brain regions were compared between groups,and the correlation of brain region volume with Montreal cognitive assessment(MoCA)score were analyzed.Results Compared with control group,in TLE group,bilateral cerebrum white matter,right globus pallidus,left posterior cingulate gyrus,left precentral gyrus,right fusiform gyrus,left cerebellum white matter,corpus callosum,left hippocampus(HBT segmentation and conventional segmentation)and right thalamus volumes decreased significantly(all P＜0.05),while right choroid plexus volume increased significantly(P＜0.05).The volume of left hippocampus(HBT segmentation)and right fusiform gyrus were both positively correlated with MoCA score in TLE group(r=0.335,0.376,P=0.009,0.007).Conclusion Widespread atrophy of brain regions could be seen in TLE patients,which were correlated with cognitive function.

Objective:To analyze the short-term hospital-based transmission characteristics and gene variation of Carbapenem-Resistant Klebsiella pneumoniae (CRKP) by genome-wide technique to provide evidence for transmission control. Methods:The experimental strain was derived from all the CRKP isolated in Affiliated Hospital of North China University of Science and Technology from October 2022 to December 2023. Strain identification and drug susceptibility were tested with VITEK 2-Compact automatic bacterial identification drug susceptibility analyzer or disk method, and the results were interpreted through whole genome sequencing. The ST type, carbapenem resistance gene, virulence factor, and O serotype of the collected strains were analyzed.Results:Among the 115 strains of CRKP, 94 strains were isolated from the intensive care unit (ICU), accounting for 81.7%, and 21 strains were isolated from the non-intensive care unit (NICU), accounting for 18.3%. The 115 strains of CRKP can be divided into 11 ST types, of which ST11 type was the most (54.8%, 63/115), followed by ST15 type (22.6%, 26/115) and ST5492 type (15.7%, 18/115). Type ST5492 was a new clonal group in the region. The 115 strains of CRKP could be divided into 7 O serotypes, most of which were O2a type(32.2%,37/115), followed by O5 type(30.4%,35/115) and O1 type(27.8%,32/115). The resistance genes of carbapenem antibiotics showed that there were 107 strains carrying the blaKPC-2 gene, one strain with the blaNDM-1 gene, and one strain with both the blaKPC-2 and blaNDM-13 genes. Virulence genes were detected in 55 CRKP strains (47.8%, 55/115), among which six strains detected peg-344, iucA, iroB, rmpA, and rmpA2 virulence genes (5.2%, 6/115). Four virulence genes ( peg-344, iucA, rmpA, and rmpA2) were detected in 34 strains (29.6%, 34/115). Three virulence genes ( iucA, iroB and rmpA) were detected in two strains (1.7%, 2/115). Three virulence genes ( peg-344, iucA and rmpA) were detected in one strain (0.8%, 1/115). IucA and rmpA virulence genes were detected in 12 strains (10.4%, 12/115). KPC-2_ST11_O2a, KPC-2_ST15_O1 and KPC-2_ST5492_O5 were dominant clones, and their distribution was mainly in the intensive care unit. The whole genome sequence analysis showed that there were three dominant clones, among which ST11 clones were subdivided into three dominant O serotypes, all of which were mainly in the intensive care unit. Conclusion:The popular strain in the hospital of CRKP is a KPC-2_ST11 clone group carrying iucA, rmpA/rmpA2, with cross-department transmission and mutation. ST5492 is a newly-launched clone type. The intensive care unit of hvKP carrying five virulence genes, including peg-344, should be alert to the epidemic risk of CR-hvKP outbreak.

Postmenopausal osteoporosis (PMOP), a bone metabolic imbalance disorder induced by estrogen deficiency, necessitates novel prevention and treatment strategies that transcend the constraints of conventional therapeutic approaches. Melatonin, a signaling molecule secreted by the pineal gland, plays a key role in maintaining circadian rhythms and regulating bone metabolism. In recent years, numerous studies both domestically and internationally have demonstrated that melatonin can promote the generation of osteoblasts and osteoclasts, thereby increasing bone density and improving symptoms of osteoporosis. This article reviews the role of melatonin in the prevention of PMOP, aiming to provide new ideas for the diagnosis and treatment of PMOP.