Objective To investigate the effects of low background radiation environments in deep underground settings on the biological behavior of NP69 human nasopharyngeal epithelial cells(NP69 cells)and the underlying molecular mechanisms.Methods A parallel control experimental design was adopted and NP69 cells were synchronously cultured in settings of three underground depths at the China in situ Deep-Underground Facility&Life Observatory(DeUFO)—ground level(DeUFO-0 m),1 000 m underground(DeUFO-1 000 m),and 1 500 m underground(DeUFO-1 500 m).Changes in cell proliferation and migration capabilities were assessed using the Cell Counting Kit-8(CCK-8)assay and scratch assay,respectively.High-throughput RNA sequencing(RNA-Seq)was performed to identify differentially expressed genes(DEGs).Functional annotation and pathway enrichment analysis of the DEGs were performed using the Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)databases.Results CCK-8 assay revealed that,after 72 h of culture,the absorbance value of the DeUFO-0 m group was 1.35 times and 1.27 times those of the those of the DeUFO-1 000 m and DeUFO-1 500 m groups,respectively(both P<0.000 1).After 96 h of culture,the absorbance value of the DeUFO-0 m group was 1.52 times and 1.41 times those of the DeUFO-1 000 m and DeUFO-1 500 m groups,respectively(both P<0.000 1).Colony formation assays revealed that the number of cell colonies in the DeUFO-0 m group was 1.59 times and 1.27 times those in the DeUFO-1 000 m group and DeUFO-1 500 m group,respectively(both P<0.001).The scratch assay revealed that the 36-hour wound healing rate of the DeUFO-0 m group was 2.22 times and 4.00 times those of the DeUFO-1 000 m group and DeUFO-1 500 m group,respectively(both P<0.000 1).Transwell assays revealed that the number of migrating cells in the DeUFO-0 m group was 2.08 times and 2.56 times those in the DeUFO-1 000 m group and DeUFO-1 500 m group,respectively(both P<0.000 1).Transcriptome sequencing analysis revealed consistent upregulation of CELF2,CELF4,CGB8,GRHL2,and DMRTA2 genes in the DeUFO-1 000 m and DeUFO-1 500 m groups.Pathway enrichment analysis indicated significant enrichment of extracellular matrix(ECM)remodeling-associated pathways and gene expression regulation pathways in the experimental groups(false discovery rate[FDR]<0.05).Conclusion The low background radiation environment in deep underground settings suppresses the proliferation and migration activities of NP69 cells by mediating ECM remodeling and post-transcriptional regulatory mechanisms through the regulation of target genes such as the CELF family.This study provides experimental evidence for establishing a dose-response relationship between environmental radiation and cellular effects.

Objective:To compare the clinical outcomes between percutaneous Kirschner wire leverage plus plaster fixation and elastic intramedullary nailing in the treatment of radial neck fractures in children.Methods:A retrospective study was conducted to analyze the 60 children with radial neck fracture who had been treated by percutaneous Kirschner wire leverage plus plaster fixation at Department of Pediatric Orthopedics, Children's Hospital of Soochow University from January 2016 to July 2023 (set as an internal fixation-free group). They were 30 males and 30 females (34 left and 26 right sides) with an age of (7.7±3.0) years. At the same time, another cohort of 60 patients were chosen as an intramedullary nailing group who had been treated by percutaneous Kirschner wire leverage plus elastic intramedullary nailing and matched in age and gender with those in the internal fixation-free group. The preoperative fracture angulation, operative time, hospitalization time, fracture angulation on the first postoperative day, fracture angulation at 1 month postoperatively, rate of angulation loss after reduction, Mayo elbow performance score (MEPS) at the last follow-up and complications were compared between the 2 groups.Results:There was no significant difference between the 2 groups in their preoperative general data, showing comparability ( P<0.05). The 120 pediatric patients were followed up for (7.5±3.2) months. The operative time [(27.4±15.0) min] and hospitalization time [(3.4±1.9) d] in the internal fixation-free group were significantly shorter than those in the intramedullary nailing group [(45.4±13.5) min and (4.4±1.3) d] ( P<0.05). The preoperative fracture angulation (50.8°±1.9°), fracture angulation on the first postoperative day (11.3°±1.2°), fracture angulation at 1 month postoperatively (12.1°±1.3°), rate of angulation loss after reduction (2.9%±0.5%), and MEPS at the last follow-up [(90.4±2.0) points] in the internal fixation-free group showed no significant differences from those in the intramedullary nailing group [49.5°±1.7°, 11.1°±1.2°, 13.3°±1.5°, 3.9%±1.4%, and (90.2±2.3) points] ( P>0.05). None of the patients in the internal fixation-free group developed pin-tail irritation sign or premature epiphyseal closure after surgery, whereas 3 patients in the intramedullary nailing group developed pin-tail irritation sign and 2 ones premature epiphyseal closure after surgery, showing a significant difference in the complication rate between the 2 groups [0 (0/60) versus 8.3% (5/60)] ( P<0.05). Conclusions:Percutaneous Kirschner wire leverage plus plaster fixation and close elastic intramedullary nailing can both achieve satisfactory outcomes in the treatment of radial neck fractures in children. However, percutaneous Kirschner wire leverage plus plaster fixation needs shorter operative time and hospitalization time, leads to fewer complications, and requires no reoperation to remove internal fixation.

ObjectiveTo study the effects of Epimedii Folium polysaccharides on mice with exercise-induced fatigue and explore its possible mechanism of action. MethodICR male mice screened by swimming training were randomly divided into a control group， model group， vitamin C group， and low， medium， and high dose groups of Epimedii Folium polysaccharides， with eight mice in each group. The exercise-induced fatigue model was established by weight-bearing swimming training in each group except for the control group. After two weeks of weight-bearing swimming， the Epimedii Folium polysaccharide groups were given 100， 200， 400 mg∙kg^-1 of Epimedii Folium polysaccharides by gavage， and the vitamin C group was given 200 mg∙kg^-1 of vitamin C by gavage. The control group and the model group were given equal amounts of saline for 14 d. At the end of the experimental period， the body mass of the mice in each group and the time of last swimming due to exhaustion were recorded. Serum urea nitrogen （BUN）， lactic acid （LA）， lactate dehydrogenase （LDH）， malondialdehyde （MDA）， superoxide dismutase （SOD）， glutathione peroxidation （GSH-Px）， myoglycogen （MG） in skeletal muscle， hepatic glycogen （HG） in the liver were detected by kits. Hematoxylin-eosin （HE） staining was used to observe the pathological changes in muscle tissue. Western blot was used to detect the protein expression of p38 mitogen-activated protein kinase （p38 MAPK）， phosphorylation （p）-p38 MAPK， extracellular signal-regulated kinase1/2 （ERK1/2）， nuclear factor-κB （NF-κB）， p-NF-κB， interleukin-1β （IL-1β）， and interleukin-6 （IL-6） in muscle tissue. The immunofluorescence （IF） method was used to detect the expression of tumor necrosis factor-α （TNF-α） in skeletal muscle tissue of mice in each group. ResultCompared with the control group， the body mass of mice in the model group decreased， and the time of last swimming due to exhaustion decreased （P<0.01）. In addition， there were significantly higher serum levels of the fatigue metabolites LA， LDH， BUN， and lipid peroxidation product MDA （P<0.01） and decreased levels of MG， HG， SOD， and GSH-Px （P<0.01）. The protein expressions of p-p38 MAPK， ERK1/2， p-NF-κB， IL-1β， IL-6， and TNF-α in skeletal muscle tissue were significantly higher than those of the control group （P<0.01）. Compared with the model group， the body mass and time of last swimming due to exhaustion of the mice in the low， medium， and high dose groups of Epimedii Folium polysaccharides and the vitamin C group were increased （P<0.05， P<0.01）， and the contents of LA， LDH， BUN， and MDA were significantly decreased （P<0.05， P<0.01）. The levels of MG， HG， SOD， and GSH-Px increased （P<0.05， P<0.01）， and the protein expression levels of p-p38 MAPK， ERK， p-NF-κB， IL-1β， IL-6， and TNF-α in skeletal muscle tissue decreased （P<0.05， P<0.01）. ConclusionEpimedii Folium polysaccharides can play a role in alleviating exercise-induced fatigue by inhibiting the p38 MARK/NF-κB signaling pathway， thereby reducing the accumulation of metabolites， improving the activity of antioxidant enzymes， increasing the glycogen content of the body， and reducing inflammation in skeletal muscle.

BACKGROUND: Osteonecrosis of the femoral head (ONFH) following internal fixation of femoral neck fractures is difficult to be cured in clinic.OBJECTIVE: To analyze the literatures concerning ONFH in patients with femoral neck fractures treated with screw internal fixation in recent 15 years, and to summarize the research progress in views of epidemiology, etiology, diagnosis,treatment and rehabilitation.METHODS: Databases of CNKI, WanFang, CqVip, PubMed, Medline, Web of Science were searched with the keywords of femoral neck fracture, osteonecrosis of femoral head, osteonecrosis, internal fixation, internal fixation with screw in English and Chinese, respectively. Afterwards, the reviews and case reports were excluded. RESULTS AND CONCLUSION: (1) A total of 54 eligible articles addressing the ONFH following internal fixation for femoral neck fractures were included, and the incidence of ONFH varied from 8.1% to 37.2%, which was found at an average of 17 months after injury. (2) ONFH was found to be related to age, preoperative fracture displacement, preoperative traction,reduction condition, time from injury to operation, elderly patients companied with other diseases, older patients undergoing removal of the screws, closed or open internal fixation, restored time postoperatively, high body mass index, hyperlipidemia, season, and depression. (3) Early prevention and remedial surgery were used to treat ONFH. (4) The patients without weight-bearing activities at 3-6 months postoperatively could be beneficial for functional recovery. (5) These results suggest that choosing appropriate surgical programs and rehabilitation plan can reduce the incidence of ONFH and achieve good treatment outcomes, such as reasonable preoperative planning, standardized operation skills, correct diagnosis and treatment, proper postoperative rehabilitation and good doctor-patient cooperation.