ABSTRACT
Objective·To study the relationship between evolution and the developmental process from the perspective of DNA sequence conservation,and explore their inherent principles.Methods·First,conservation rate(CR)was established by analyzing the conservation of amino acid sequences of coding genes in 100 species to quantify the evolutionary conservation of genes.The relationship between CR and developmental potential was verified by using the feature genes involved in embryonic stem cells pathways.Secondly,cell type-specific genes and their characteristics in conservation were studied by analyzing the RNA sequencing(RNA-seq)data of the three early germ layers(ectoderm,mesoderm and endoderm)and their corresponding mature organs(brain,heart,liver,etc).Then,chromatin immunoprecipitation sequencing(ChIP-seq)data of enhancer histone H3 acetylated at lysine 27(H3K27ac)from early germ layers and mature organs were collected to search for enhancer sites and identify super enhancers in various cells and tissues by using the ROSE procedure.Functional enrichment and signaling pathway analysis of genes was used to examine the identity correlation between SEs-regulated genes and the corresponding cell characteristics,to clarify whether the SEs identified in this study were consistent with the characteristics reported in previous studies.Finally,PhastCons program was used to calculate the DNA conservation score(CS)of non-coding regulatory regions to study their relationship with developmental potential.Results·In the coding region of DNA,CR was successfully established to quantify the conservation of genes.The gene expression data of early germ layers and mature organs showed that the genes with higher conservation rate were more relevant to the stemness and early developmental process,and the differences between the tissues from early and late development could be distinguished by using CR.In the non-coding regions of DNA,it was found that the conservation of regulatory regions was also correlated with development.The CS of the SE sequences in the early developmental germ layers was significantly higher than that of the SE sequences in the corresponding mature organs.However,cell-specific typical enhancers(TEs)did not show such a trend.Conclusion·During the developmental process,CR of genes expressed in the coding region decreases,and CS of super-enhancer DNA in the non-coding region decreases.
ABSTRACT
Objective:To investigate the role of lncRNA H19 in evaluating prognosis and regulating radioresistance of colon cancer, aiming to provide a new potential target for the diagnosis and treatment of colon cancer.Methods:The value of lncRNA H19 in the clinicopathological parameters and prognosis of colon cancer was assessed based on bioinformatics technology. The expression of lncRNA H19 in HCT116 and SW620 cells was regulated through siRNA and overexpression plasmid transfection, respectively. The effect of regulating lncRNA H19 expression on the proliferation, DNA synthesis, radiosensitivity and cell cycle of colon cancer cells after X-ray irradiation were detected by CCK8, EdU, cell clonogenic survival assay and flow cytometry.Results:The expression of lncRNA H19 was significantly upregulated in colon cancer tissues and correlated with poor prognosis in colon cancer patients. LncRNA H19, as a high-risk gene for colon cancer, had a significant advantage for prognostic assessment of colon cancer (AUC=0.816). Furthermore, the expression of lncRNA H19 was upregulated after X-ray irradiation in colon cancer cells. Knockdown of lncRNA H19 (siRNA-H19) significantly increased the radiosensitivity in HCT116 cells, while overexpression of lncRNA H19 (H19-OE) enhanced the radioresistance in SW620 cells. Moreover, flow cytometry revealed that the G 2/M phase arrest induced by X-ray irradiation was obviously aggravated after siRNA-H19 treatment in colon cancer cells, which suggested that lncRNA H19 might regulate the radiosensitivity by inhibiting cell cycle progression. Conclusion:LncRNA H19 plays a key role in the prognostic assessment and regulating the radiosensitivity in colon cancer, which can be used as a potential target for improving radiosensitivity of colon cancer radiotherapy.
ABSTRACT
Objective To analyze the status and control effects on coal-burning-borne endemic fluorosis in Zunyi City,Guizhou Province,and to provide a scientific basis for sustainable prevention and control of endemic fluorosis.Methods All diseased villages of 5 counties of Zunyi City in 2014,survey results of the dental fluorosis of children aged 8-12,the use of improved stoves and stoves for all residents of the diseased villages,the proper drying conditions for corn and peppers,were analyzed.The diagnosis was based on "the Diagnosis of Dental Fluorosis" (WS/T 208-2011).Results Dental fluorosis of 115 840 children were examined,the prevalence rate of dental fluorosis was 5.85％ (6 773/115 840) in 5 diseased districts.A total of 444 196 households in Zunyi City were investigated,the qualified rate of improved stoves and the correct-usage rate of qualified stoves were 99.53％ (442 108/444 196) and 99.34％ (441 256/444 196),respectively;the proper drying conditions of corn and peppers was 99.26％ (440 903/444 196).Conclusions The control efficiency for coal-burning-borne fluorosis in Zunyi City is obvious.We will continue to strengthen the health intervention and post-management efforts to consolidate the results of elimination of fluorosis.
ABSTRACT
Objective To understand the city residents' iodine nutrition level after implementation of a new iodine concentration standard.Methods Using random sampling,four counties were selected to monitor iodine nutrition level;in every county 50 children aged 8-l0 and 20 pregnant women were selected as monitoring subjects;B ultrasound scan was used to detect goiter and children urinary iodine and salt iodine levels were tested;urinary iodine concentration of pregnant women and nursing mothers was determined.Results Thyroid of 200 children aged 8-10 years were detected,the enlargement rate of thyroid gland was 1％ (2/200);200 salt samples were tested,qualified iodized salt consumption rate was 96％ (192/200);200 copies of children urine samples were tested,the median of urinary iodine was 229.3 μg/L;80 copies urine samples of pregnant women were tested,urinary iodine median was 183.7 μg/L.Conclusions After implementation of a new standard of salt iodine content,the iodine nutrition level of children in the four counties (districts) of Zunyi is still high,but the level of iodine nutrition of pregnant women appears imbalanced.We suggest to supply different concentrations of iodized salt for different groups of people,to strengthen the monitoring,and to prevent iodine deficiency disorders.