Objective: To understand the prevalence of dental caries and its influencing factors among primary and middle school students in the Xinjiang Production and Construction Corps (hereinafter referred to as "the Corps"), so as to provide a reference for formulating targeted prevention strategies and promoting oral health of primary and middle school students. Methods: Primary and middle school students in the Corps were selected as survey subjects by a multi-stage stratified random cluster sampling method in September 2023. Basic information and dietary behaviors were collected through questionnaire surveys, and dental caries status was examined by oral health technicians. Multivariable logistic regression model was used to analyze the influencing factors of dental caries among primary and middle school students. Results: A total of 80 370 primary and middle school students were investigated, including 40 582 males (50.49%) and 39 788 females (49.51%). There were 37 608 primary school students (46.79%), 34 612 junior high school students (43.07%), and 8 150 senior high school students (10.14%). There were 26 669 students with dental caries, with a prevalence rate of 33.18%. Multivariable logistic regression analysis showed that the risk of dental caries was higher among female students (OR=1.170, 95%CI: 1.136-1.206), students in suburban counties (OR=1.212, 95%CI: 1.166-1.258), boarding students (OR=1.306, 95%CI: 1.257-1.357), and those with a frequency of fried food intake ≥1 time per day (OR=1.175, 95%CI: 1.084-1.273). Conversely, the risk of dental caries was lower among middle school students (OR=0.542, 95%CI: 0.524-0.560), high school students (OR=0.661, 95%CI: 0.620-0.705), and those with a frequency of vegetable intake ≥1 time per day (1 time per day, OR=0.900, 95%CI: 0.838-0.967), (≥2 time per day, OR=0.879, 95%CI: 0.819-0.944), and those who sometimes ate breakfast (OR=0.907, 95%CI: 0.874-0.942). Conclusions The prevalence of dental caries among primary and middle school students in the Corps is relatively high, and is influenced by various factors such as gender, school stage, area, boarding status, and dietary behaviors. It is suggested to strengthen oral health knowledge education among students, conduct regular oral health examinations, and improve the overall level of oral health.

Strengthening the cultivation of innovation ability is the new requirement put forward by the state for higher educa-tion.High-quality curriculum design is the primary means of achieving high-quality talent cultivation.By constructing the"disease case library"and"problem graph"of immune system and related diseases,and adopting the teaching method of"combining large and small cases and integrating online and offline",this study not only consolidates students'basic knowledge,but also builds a bridge for students from theory to practice,from knowledge accumulation to creation and application.It further exercises students'ability to dis-cover,analyze and solve problems,and enhances students'innovation awareness and ability.

Objective:To investigate the incidence of shoulder work-related musculoskeletal disorders (WMSDs) among occupational population in China, and to explore their intrinsic association with personal and work-related factors.Methods:In April 2024, 73497 valid questionnaires of the Chinese version of the Musculoskeletal Disorders Electronic Questionnaire were retrospectively analyzed from June 2018 to December 2023 in 22 provinces and 29 key industries in China, and the general information, occurrence of WMSDs and related risk factors of key occupational populations in different regions in China were collected. By using Chi-square test and confirmatory factor analysis, the relationship between shoulder fatigue and pain in key occupational groups and individual factors, work type, work posture and work organization was discussed, and the internal relationship was analyzed based on structural equation model.Results:Higher incidence of shoulder fatigue and pain were associated with female, lack of physical exercise, uncomfortable working posture and neck leaning forward ( P<0.05). Structural equation model analysis showed that work type, work posture and work organization were strongly correlated ( r=0.58, 0.55). Work organization and work type were strongly correlated with shoulder fatigue ( r=0.65) and moderately correlated with shoulder fatigue ( r=0.21). Shoulder fatigue was moderately associated with shoulder pain ( r=0.40). Individual factors, work type, work posture and shoulder fatigue could directly affect shoulder pain ( OR=0.07, -0.09, 0.17 and 0.40), and work type and work posture could also indirectly affect shoulder pain through shoulder fatigue ( OR=0.08, 0.03). Work organization only indirectly affected shoulder pain through shoulder fatigue ( OR=0.26) . Conclusion:The main influencing factor of shoulder pain is shoulder fatigue, followed by work posture and individual factors. Structural equation model can better reflect the complex relationship between work type, work posture and work organization and shoulder WMSDs. Improving work posture and work organization may be an effective way to control the influence of shoulder fatigue on shoulder pain.

Objective:To explore the structural relationship between WMSDs in the upper limbs and various risk factors in the occupational population in China, based on a large sample epidemiological survey and structural equation analysis, and to establish a structural equation model, so as to lay a foundation for the prevention and control of such diseases.Methods:The Chinese version of the Musculoskeletal Disorders Electronic Questionnaire was used to conduct a nationwide survey on the prevalence of WMSDs in the upper extremity. Six factors related to WMSDs in the upper extremity were extracted by the classification standard of adverse ergonomic factors and their source and confirmatory factor analysis, including work organization, work type, upper extremity work posture, individual factors, upper extremity fatigue and upper extremity WMSDs. The structural equation analysis was carried out and the structural equation model was established.Results:The incidence of WMSDs and fatigue in the upper limbs was 24.44% and 43.76%, respectively. The adjusted structural equation model fitting indicators were generally up to the standard (GFI=1.000, AGFI=1.000, RMSEA=0.043, NFI=0.808, TLI=0.784) . The four exogenous latent variables of work organization, work type, upper limb work posture and individual factors were correlated. There was a strong positive correlation between job type and upper limb work posture ( r=0.865) , a moderate positive correlation between work organization and job type and upper limb work posture ( r=0.570, 0.490) , and a weak negative correlation between individual factors and the other three exogenous latent variables. Upper limb work posture and individual factors had direct effects on upper limb WMSDs, and the effect coefficients were 0.10 and 0.06, respectively. Upper limb fatigue played a mediating role between work organization, work type, upper limb work posture and upper limb WMSDs. The effect coefficient was 0.46, and the composition ratios of indirect effects were 100.0%, 100.0%, and 38.3%, respectively. The direct path effect of upper limb work posture, individual factors and upper limb WMSDs was weaker than the mediating path through upper limb fatigue. Conclusion:When carrying out the prevention and control of upper limbWMSDs, it is necessary to comprehensively consider the pathogenesis path of upper limb muscle fatigue and upper limb WMSDs caused by work organization, work type, and upper limb work posture, so as to provide theoretical reference for improving the prevention and control level of such diseases.

Objective To map the genome-wide distribution profile of histone H3K27me3 modification in diffuse gastric cancer tissues,identify target genes regulated by H3K27me3,and primarily explore the potential mechanism of its modification reprogramming in the occurrence and development of the tumor.Methods Normal gastric mucosal tissues and diffuse gastric cancer tissues were harvested from the patients who underwent examinations or treatments in the departments of gastroenterology and gastrointestinal surgery of our medical center between 2021 and 2023.There were 14 patients in the normal group(6 males and 8 females,average age of 46 years)and 14 patients in the gastric cancer group(8 males and 6 females,average age of 63 years).Cleavage under target and tagmentation(CUT&Tag)technology was employed to capture genomic regions modified by H3K27me3,and analyze the reprogramming characteristics of these modifications.RNA sequencing data,data from high-throughput chromosome conformation capture(Hi-C)technology,and publicly available single-cell data were integrated to investigate the target genes regulated by the reprogramming of H3K27me3 modifications in diffuse gastric cancer cells.Results The quality of the CUT&Tag and RNA sequencing data met the standards required for subsequent analysis.Histone H3K27me3 modifications in normal gastric mucosa and diffuse gastric cancer tissues were primarily distributed in distal intergenic regions and intronic regions.In gastric cancer tissues,compared to normal tissues,there was significant reprogramming of H3K27me3 modifications,characterized by a marked reduction in overall H3K27me3 signal intensity.The loss of 2 912 H3K27me3 signal peaks might lead to the up-regulation of 822 tumor-associated genes.Among them,56 genes displayed the most significant up-regulation(fold change in signal intensity≥2,P<0.05),with notable enrichment in the mammalian target of rapamycin complex 1(mTORC1)signaling pathway.Specifically,the methionine transporter SLC7A5 and the cystine transporter SLC7A11 were found to have the highest expression levels in gastric cancer tissues.Single-cell data revealed that the abnormal overexpression of SLC7A11 in diffuse gastric cancer was primarily observed in tumor epithelial cells.Further validation using public data and immunohistochemical experiments confirmed the elevated expression of SLC7A11 in diffuse gastric cancer,which is associated with poor prognosis in gastric cancer patients.Conclusion The reprogramming of histone H3K27me3 modification is an important epigenetic characteristic in diffuse gastric cancer.Loss of H3K27me3 signal peaks may up-regulate the expression of SLC7A11 in diffuse gastric cancer cells,and thereby promote tumor progression.

Objective To map the super-enhancers remodeling of intestinal gastric cancer and reveal the tumor biological functions of the super-enhancers and the downstream target genes that may be activated.Methods A total of 31 normal gastric mucosal tissues,23 intestinal gastric cancer tissues and 9 intestinal gastric cancer organoids were collected from the Department of Gastroenterology of Army Medical Center of PLA from January to December 2022.Chromatin targeting histone H3K27ac modified chromatin targeting cleavage under targets and tagmentation(CUT&Tag)sequencing was conducted on above tissues.The remodeling profiles of super-enhancers in intestinal gastric cancer were analyzed and the key target genes were identified based on bioinformation tools.CRISPRi technology was used to intervene with the super-enhancers,the expression of target genes was detected with Western blotting,and the proliferation,migration and invasion abilities were detected by CCK-8 assay and Transwell chambers in the control group and the intervention group.Results There was a significant difference in the signal of super-enhancers between intestinal gastric cancer tissues and normal gastric mucosal tissues(P<0.05),and the active super-enhancers in cancer tissues may be involved in biological processes such as negative regulation of the immune system and cell adhesion.The expression of up-regulated cell migration-inducing protein(CEMIP)in tumor cells was regulated by the super-enhancers,and intervening the super-enhancers down-regulated the expression of CEMIP(P<0.05),and inhibited the cell proliferation,invasion and migration abilities of tumor cells(P<0.05).Conclusion Super-enhancer remodeling is observed in intestinal gastric cancer,and they can up-regulate the expression of CEMIP gene and promote the growth,migration and invasion of cancer cells.

Objective To draw the genome-wide distribution and remodeling characteristics of H3K27me3 silencers in signet-ring cell carcinoma of the stomach(SRCC)through epigenetic sequencing technology,and to investigate their roles in transcriptional regulation in order to elucidate the regulatory mechanism of SRCC malignant progression.Methods The study was conducted on 35 gastric samples obtained by gastroendoscopic biopsy(15 normal and 20 SRCC tissues)from Department of Gastroenterology of Army Medical Center of PLA between January 2021 and December 2023.Multi-omics analyses,including assay for transposase-accessible chromatin with high-throughput sequencing(ATAC-seq),cleavage under targets and tagmentation(CUT&Tag)and transcriptome sequencing(RNA-seq),were performed to identify chromatin accessibility,H3K27me3 silencer regions,and transcriptional changes,with aid of Illumina NovaSeq 6000.H3K27me3 related differentially expressed genes(|Log2FC|>1,FDR<0.05)were screened using DESeq2.Gene Ontology(GO)analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis were employed to analyze the enrichment function,and Homer was employed to identify transcription factor motifs.A regulatory network was constructed using Cytoscape,and then validated using immunohistochemistry to explore its regulatory mechanism.Results H3K27me3 silencers were primarily located in distal intergenic regions(37.06%)in SRCC.Compared with the normal tissues,SRCC showed a significant reduction in H3K27me3 silencer signals(95%CI:1.34～2.30,P=0.007)with 6 257 lost sites(FDR<0.01).Integrating CUT&Tag and RNA-seq revealed 380 up-regulated immune-related genes,particularly in T cell receptor signaling(OR=4.2,95%CI:2.8～6.3,P=0.002).Immunohistochemistry confirmed elevated expression of transcription factor EHF(P<0.05).Conclusion There is the remodeling of H3K27me3 silencers in SRCC,and EHF may potentially play a crucial role in the SRCC malignant progression.

Objective To identify the enhancer profile marked by histone H3K27ac modification in high-grade intraepithelial neoplasia(HGIN)in order to reveal the novel regulatory mechanism of HGIN pathogensis.Methods Gastric tissue samples were collected from Department of Gastroenterology of Army Medical Center of PLA between June 2022 and June 2023,including 14 normal gastric tissues(Nor group),31 HGIN tissues(HGIN group)and 17 gastric cancer tissues(GC group).Cleavage under targets and tagmentation(CUT&Tag)technique was employed to capture enhancer regions modified by histone H3K27ac.Multi-omics analysis was performed to identify HGIN-specific active enhancers and their potentially regulated genes.Immunohistochemical profiling was performed to assess differential expression of the gene of interest across clinically stratified specimens,combined with CRISPR-dCas9-mediated ablation of active enhancers to monitor the gene of interest transcriptional dynamics and validate enhancer-mediated regulatory mechanisms.Results Epigenomic sequencing obtained the data with excellent quality,and indicated that obvious remodeling was observed in H3K27ac enhancers in HGIN and GC groups(P<0.05),though no significant difference in the genome-wide distribution of H3K27ac modification among the 3 groups.Combining transcriptome data revealed that enhancer remodeling may up-regulate the expression of the proliferation-related target gene,CD24,in the HGIN tissue;while,inhibiting enhancer activity can notably reduce CD24 expression level(P<0.05).Immunohistochemical assay displayed a positive correlation between the expression levels of CD24 and Ki-67(P<0.001).Conclusion The remodeling of H3K27ac enhancer represents a significant epigenetic feature of the transformation from normal condition to HGIN.Remodeling of H3K27ac enhancer up-regulates CD24,which may facilitate the abnormal proliferation of gastric epithelial cells.

Objective To analyze clinical characteristics of mesenchymal-subtype gastric cancer(Mes-GC)by integrating multi-omics data and explore the characteristics of tumor cells and microenvironment associated with the risk for recurrence.Methods Gastric tumor tissue samples were collected from the patients who visited Department of Gastroenterology of Army Medical Center of PLA from January 2022 to December 2023.Transcriptome and genome sequencing were applied for these tissue samples,including 19 cases of diffuse-type gastric cancer,22 cases of intestinal-type gastric cancer,and 23 cases of mixed-type gastric cancer patients.Bioinformatics analysis was employed to investigate the differences in clinical characteristics and tumor microenvironment between Mes-GC and non-mesenchymal-subtype gastric cancer(non-Mes-GC)by integrating data resources including The Cancer Genome Atlas(TCGA),Gene Expression Omnibus(GEO),and National Genomics Data Center(NGDC).Results Compared to non-Mes-GC patients,Mes-GC ones were characterized by later clinical stages,deeper tumor infiltration,and higher rates of lymph node metastasis.Kaplan-Meier survival analysis confirmed that Mes-GC patients were associated with shorter survival time,poor prognosis as well as increased risk of cancer recurrence(P<0.05).Single-cell RNA sequencing data revealed that tumor cells in Mes-GC showed higher expression levels of the genes related to stemness,metastasis(P<0.05),and epithelial-mesenchymal transition(EMT).And in the tumor microenvironment,there were significant more myeloid cells,smooth muscle cells,endothelial cells and fibroblasts,with the most pronounced elevation in the proportion of fibroblasts(P<0.05).Moreover,the patients with larger proportion of fibroblasts were associated with poorer prognosis.Conclusion Mes-GC tumor cells exhibit higher stemness and EMT characteristics,and stromal cells such as myeloid cells,endothelial cells,and fibroblasts are enriched in the tumor microenvironment.These features may be key factors contributing to poor prognosis and high recurrence rate of Mes-GC.

Objective To identify the enhancer landscape marked by histone H3K27ac modifications in diffuse-type gastric cancer(DGC)tissues,and to elucidate the epigenetic remodeling mechanisms by which active enhancers regulate cachexia-related genes.Methods Gastric mucosal tissue samples were collected from Department of Gastroenterology of Army Medical Center of PLA during January 2022 to March 2023,including 10 normal gastric mucosa tissues(Normal group),10 DGC tissues diagnosed with cachexia(DGC group),and 10 organoids derived from DGC tissues(Organoid group).Using H3K27ac chromatin targeting cleavage and tagmentation(CUT&Tag)technology,genomic modification regions were captured to screen specific active enhancers and their potential target genes in DGC tissues.CRISPR-dCas9 gene editing technology was used to intervene with the enhancers,and the expression of target genes was detected with Western blotting and qRT-PCR.Sixteen female SPF-grade BALB/c Nude mice(6～8 weeks old,weighing 18～21 g)were utilized to establish an orthotopic xenograft tumor model using the human diffuse-type gastric cancer cell line MKN45.Cachexia-related phenotypes were evaluated in 3 groups:normal group(n=4),silencing group(n=6),and control group(n=6).Results Significant differential enhancer regions were identified between DGC and normal gastric mucosa tissues.DGC tissues exhibited a marked increase in enhancer abundance(P<0.05)and signal intensity when compared with the normal counterparts.Integrated analysis of transcriptome data revealed that some of these active enhancers up-regulated the expression of GDF15,a cachexia-associated target gene in DGC.Targeted silencing of the active enhancer of GDF15 using CRISPR/dCas9-KRAB plasmid technology resulted in a significant reduction in GDF15 expression at both mRNA levels(P<0.05)and protein.Results from orthotopic transplantation experiments of DGC demonstrated that silencing of active enhancers alleviated the cachexia phenotype in nude mice(P<0.05).Conclusion DGC exhibits enhancer remodeling,which regulates the expression of the cachexia-associated gene GDF15,and thereby contributes to the pathogenesis and progression of cancer cachexia.