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 explore the model of first aid skills training based on competition.Method:The second-year residents who participated in the competition in 2021 ( n = 142) were selected. According to whether they attended BLS training in the first year, they were divided into group A ( n = 88) who attended BLS training and group B ( n = 54) who did not. Chi-square test, T test, Wilcoxon rank sum test and Logistic regression were used in our study. Results:There was no significant difference in gender and specialty between both groups (female, 62.5% vs. 68.5%, P= 0.466; TCM, 50% vs. 53.7%, P= 0.668), but the real resuscitation experience of group A was more than that of group B (40.9% vs. 9.3%, P= 0.000). The qualified rate of CPR and the compression score in group A was higher than that in group B [(81.8% vs. 61.1%, P = 0.006; (30±5) vs. (25 ±10), P= 0.001], including compression frequency, depth, rebound and compression/respiration rate (73.9% vs. 55.6%, P= 0.024; 88.6% vs. 70.4%, P= 0.006; 96.6% vs. 87%, P= 0.031). In the theoretical examination, the correct rates of electrocardiogram [(53.63±2.9)% vs. (50.44±2.57)%] and first aid medication [(57.38±3.55)%, P = 0.001] in the two groups were significantly lower than the qualified rate. After adjusting other factors, Logistic regression analysis showed that the CPR qualification rate in group A was 2.769 times higher than that in group B ( P= 0.015, 95% CI 1.215~6.311) Conclusions:The first aid skills training mode based on competition can objectively reflect first aid skills level of residents. We found that the quality of CPR skills was not related to gender, specialty and real CPR experiences but experience of BLS training was an independent influencing factor. And how to identify and manage arrhythmias and how to choose different emergency drugs are urgent emergency skills for residents to improve.

The purpose of this study was to investigate the effect of low-magnitude vibration on osteogenesis of osteoblasts in ovariectomized rats with osteoporosis via estrogen receptor α(ERα). The mRNA expression of osteogenic markers were examined with qRT-PCR, based on which the optimal vibration parameter for promoting osteogenesis was determined (45 Hz × 0.9 g, g = 9.8 m/s
Animals ; Cell Differentiation ; Estrogen Receptor alpha/genetics* ; Female ; Osteoblasts ; Osteogenesis ; Osteoporosis ; Ovariectomy ; Rats ; Vibration

This study aimed to investigate biomechanical properties of synthetic implants for reconstructive surgery of pelvic floor dysfunction. In this dissertation, we chose four synthetic implants, i.e. total pelvic floor repair system (PROLIFT), gynecone TVT obtutator system (TVT-O), intra-vaginal sling placement device (IVS) and acellular dermal matrix (Renov), for tensile test respectively. The biomechanical properties of four synthetic implants were measured and analyzed using a material testing machine (Instron 4302 versatile material testing machine). The biomechanical parameters included ultimate stress strength, modulus of elasticity, maximum load and maximum elongation. The results showed that the maximum load of the four symthetic implants was TVT-O > IVS > PROLIFT > Renov, and the maximum load of TVT-O was significantly higher than PROLIFT and Renov ( < 0.05). The ultimate stress strength was TVT-O > IVS > PROLIFT > Renov, with no significant differences among them ( > 0.05). The maximum elongation of the four implants was TVT-O > PROLIFT > IVS > Renov, and the maximum elongation of TVT-O and PROLIFT were both significantly higher than Renov ( < 0.05). The modulus of elasticity was IVS > Renov > TVT-O > PROLIFT, with no significant differences among them ( > 0.05). Taken together, the present study demonstrates that the modulus of elasticity of IVS was the highest in the four synthetic implants; TVT-O had the highest mechanical strength; The maximum load, ultimate stress strength and maximum elongation of Renov were all the lowest; The mechanical properties of PROLIFT was the most stable, and its modulus of elasticity was the lowest in the four synthetic implants, which had good extensibility and elasticity. Therefore, it is necessary to pay attention to the biomechanical properties of new pelvic reconstructive materials for the clinical pelvic reconstructive surgery.