Objective To investigate the expressions of miR-16,miR-106b,miR-449a,miR-34a and let-7g in peripheral blood plasma of the residents surrounding hot springs with radon in Hebei province.Methods A total of 41 randomly selected residents surrounding hot springs with radon were considered as the radon group,and 46 residents with same living habit but without contact with hot springs were considered as control.The miRNAs in the peripheral blood plasma of these two groups were detected with qRT-PCR.Results The levels of miR-16,miR-106b,miR-449a and let-7g in the radon group were significantly higher than those in control group (Z=-2.278,-3.835,-2.719,-2.721,P＜0.05).Alterations of these miRNAs were associated with radon exposure (t =2.154,3.711,2.319,2.015,P ＜ 0.05) but had no relationship with age,sex,smoking and drinking factors.No significant difference was observed in the plasma levels of miR-34a between the two groups.Conclusions miR-16,miR-106b,miR-449a and let-7g could be applied as potential biomarkers for radon exposure.

Objective To investigate the effects of 60Co γ-ray partial radiation on chromosome aberration in human peripheral blood in vitro.Methods The samples of heparinized peripheral whole blood from 3 healthy persons were exposed to 60Co γ-rays at the doses between 0 and 8 Gy with the dose rate of 0.35 Gy/min at the temperature of 37 ℃ ,and then mixed with the unirradiated blood samples of the Microscopy was used to observe the chromosome aberration double ( centromere + centromere) and the biological dose was estimated thereby.ResultsThe amounts of double centromere + centromere were increased along with the dose of irradiation in all groups.The estimated biological dose was higher than the 1/3 of the irradiation dose when the dose was between 0.5 to 2 Gy,and was close to the 1/3 of the irradiation dose when the dose was between 4 to 8 Gy.Conclusion Chromosome aberration can be used as a biomarker in estimation of uneven irradiation.

Objective To investigate 60Co γ-ray induced damage in lymphocytes and the relationship between doses of 60Co γ-ray irradiation and the levels of phosphorylated H2AX and ATM.Methods Cells were irradiated with 60Co γ-rays in the range of 0-8 Gy.The levels of phosphorylated H2AX and ATM were detected by Western blot and FACScan,respectively.The micronucleus(MN)was analyzed by CB method to evaluate DNA damage.Results FACScan results showed the dose-effect relationship of γ-H2AX expression were linear.square at 0.5 h post-irradiation to different doses,and the fitting curve was shown as Y=3.96+11.29D-0.45D2.The level of phosphorylated ATM(p-ATM)was not changed significantly by using the same method.Western blot showed that p-ATM protein expression was significandy increased after irradiation compared with sham.irradiated group.The MN assay which represented DNA damage was sensitive to different doses.Conclusions γ-ray irradiation could induce the phosphorylation of H2AX and ATM,which may play an important role in indicating DNA damage.Both of H2AX and ATM have the potential as sensitive biomarker and biodosimeter for radiation damage.

Objective To analyze the chromosome aberrations induced by partial radiation in human peripheral blood lymphocytes in vitro.Methods Heparinized whole blood samples were exposed to 2 Gy ~(60)Co 7-rays at 37℃ ,and then mixed with non-irradiated blood by different ratio.The slides were prepared after culturing and the unstable aberrations were analyzed.Results The chromosome aberrations had a good relationship with the ratio of irradiated blood.The chromosome aberrations in partial irradiated group were higher than that in the irradiated group.The estimated dose was 1.27 Gy when the ratio was 1 : 1 ,greater than the dose of 1 Gy.The estimated dose was 0.93 Gy when the ratio was 0.5＝1,also greater than 0.5 Gy.But when the ratio was 1:0,the radiation dose was accordant with the estimated dose.Conclusions Chromosome aberrations could be a biomarker for estimating the uneven irradiation.

Objective To explore the effect of radon and its progeny on the expression and mutations of p53 in lung tissue of mouse model. Methods Apoptosis was detected by terminal deoxynucleotidy transferase-mediated dUTP-biotin nick end labeling. The expression of p53 gene was analyzed by immunohistochemistry, Western blot and realtime-PCR. PCR-SSCP was used to detect the mutation of p53 in lung tissues. Results Compared with those in the control group, the apoptotic index were increased significantly in 30 WLM and 60 WLM groups( t = 18.11, -10.30,P ＜ 0.05 ). The p53 protein was increased significantly ( t = -11.08, P ＜ 0.05; t = - 7.00, P ＜ 0.0 ) ) in 30 WLM and 60 WLM groups. The mutation of p53 gene was not detected in lungs of radon-exposure mice. Conclusions Lung and bronchus might be the targets of radon and its progeny, and p53 gene plays an important role in the progression of radon-induced lung injury.

Objective To investigate the expressions of lung cancer related genes and miRNA in peripheral blood of the residents surrounding the extremely high radon hot springs in Ruoergai County,Sichuan Province. Methods Peripheral blood samples were collected from the local residents.Expressions of lung cancer related genes (p53,k-ras) and miRNA (let-7a,miR-34a/b) were detected by real-time PCR and the protein expressions of p53 and k-ras were detected by Western blot.Results The expressions of p53 and k-ras mRNA of the residents in high radon area were 0.97 and 1.33 times of the control respectively (t =0.13,-1.12,P ＞0.05),and the p53 and k-ras protein levels were 0.70 and 1.23 times of the control respectively (t =0.72,0.46,P ＞ 0.05).The let-7a of the residents in high radon area was lower (t =1.63,P ＞ 0.05 ) while the miR-34a and miR-34b were significantly higher than those of the controls (t =- 3.20,- 3.32,P ＜ 0.05).Conclusions Based on the expressions of p53 and k-ras gene and miRNA,it can be concluded that the residents surrounding the high radon hot springs received radiation damage.

Objective CXCR4-overexpressing bone marrow-derived mesenchymal stem cells (CXCR4-BMSC) were constructed and co-cultured with hypoxia/re-oxygenation pretreated renal tubular epithelial cells (HR-RTEC).Repair of HR-RTEC was detected and the possible mechanism was also discussed.Methods CXCR4-BMSC (CXCR4-BMSC/eGFP,eGFP as the tracer gene) and null-BMSC (BMSC/eGFP) were obtained by gene transfection technique,and the level of CXCR4 in the transfected cells was detected.RTEC was cultured under hypoxia/re-oxygenation condition for 12 h,respectively,to obtain HR-RTEC,which was used to simulate AKI in vitro.BMSC and HR-RTEC were co-cultured for 12 h,and the proportion of apoptotic cells among the HR-RTEC was assayed by immunofluorescence technique.Western blot was used to test the protein levels of cleaved Caspase-3 and Bcl-2.The number of migrating BMSC was also assayed.After culturing with the HR-RTEC culture supernatant,the expression of cytokeratin 18 (CK18) in BMSC was tested by immunofluorescence staining.Cytokines including bone morphogenetic protein-7 (BMP-7),hepatic growth factor (HGF) and interleukin-10 (IL-10) in the BMSC culture supernatant were detected by ELISA method.Results Expression of CXCR4 was enhanced in CXCR4-BMSC.Proportions of the apoptotic cells among HR-RTEC after being co-cultured with BMSC,CXCR4-BMSC and null-BMSC were all decreased,especially in the C/H group.The decreased cleaved Caspase-3 and enhanced Bcl-2 were also observed in HR-RTEC.The number of migrating CXCR4-BMSC was the highest.Proportions of CK18+ cells in BMSC,CXCR4-BMSC and null-BMSC were all low and showed no difference.However,CXCR4 overexpression in BMSC stimulated secretions of BMP-7,HGF and IL-10.Conclusions CXCR4-overexpressing BMSC has more repair effect on the co-cultured HR-RTEC,the enhanced migration ability and secretion ability of CXCR4-BMSC are the possible mechanisms.

Objective:To investigate the prognostic factors and pathological characteristics of mixed subtype thyroid cancer (MSTC) .Methods:Data of 41 cases of MSTC, which were confirmed by postoperative pathology, among from 24, 912 cases of thyroid cancer admitted in Mar. 2005 to Aug. 2020 in the First Medical Center of Chinese People’s Liberation Army General Hospital, were retrospectively analyzed. 37 cases underwent surgical treatment, while 4 cases only underwent puncture to confirm the pathology due to physical conditions, and no surgical treatment was performed. The tumor size, number of lesions, capsule invasion, AJCC 8th TNM staging, surgical methods, radiotherapy and chemotherapy were collected. The MSTC patients in the group were followed up to obtain the postoperative situation. SPSS 25.0 and R studio statistical software was used for data processing, and Cox single factor and multivariate regression were used to analyze independent risk factors.Results:In the 41 cases, there were 9 cases of papillary carcinoma (PTC) mixed with follicular carcinoma (FTC) , and 8 cases of mixed medullary and follicular carcinoma (MMFTC) . There were 15 cases of poorly differentiated thyroid cancer (PDTC) , 4 cases of squamous cell carcinoma of thyroid (SCCT) , and 5 cases of undifferentiated thyroid carcinoma (ATC) . The median follow-up time was 18 months, and 11 patients died during the follow-up, with a mortality rate of 26.8%. Average onset age was (51.41+15.69) years. 4 cases had postoperative recurrence during the follow-up, including 2 cases of local recurrence, and 2 cases of distant metastasis. Single factor results showed that age, degree of tumor differentiation, surgical method, radiotherapy and chemotherapy were the risk factors affecting the prognosis of patients with MSTC ( P<0.05) . Multivariate analysis showed that age at diagnosis ( P=0.007) and surgical procedure ( P=0.017) were independent risk factors for prognosis in patients with MSTC. Conclusion:Middle-aged and elderly women are at high risk for MSTC, and the degree of tumor differentiation is proportional to survival. Due to the multi-type and pleomorphic pathological findings, a reasonable treatment plan has good effects on prognosis of MSTC.

Objective:To explore the feasibility of the optimized cytokinesis-block (CB) assay on radiation-induced nucleoplasmic bridge (NPB), and to provide a scientific basis for the application of NPB in biological dose estimation.Methods:Human peripheral blood in vitro was irradiated with 2 Gy 60Co γ-rays at a dose rate of 1 Gy/min (0 Gy control group). According to the culture time after irradiation, blood samples were divided into group 48, 56, 68 and 72 h. Cytochalasin-B (Cyt-B) with a concentration of 6 μg/ml was added into the samples at 28 h and harvested at 48, 56, 68 and 72 h after irradiation, respectively. On the other hand, the blood samples were treated with different concentration of Cyt-B i. e., 0.6, 1, 2, 6 and 10 μg/ml at the beginning of culture (0 h) and harvested at 68 h after irradiation. The proportion of mononucleated, binucleated and multinucleated cells, radiation-induced NPB and micronucleus (MN) frequencies were analyzed. Results:The nuclear division index (NDI) and proportion of binucleated cells at 2 Gy and 0 Gy had tendency of increasing with cell culture time. NPB frequencies (0.023 0-0.033 0/cell) and MN frequencies had no significantly difference ( P> 0.05). With the increase of Cyt-B concentration, NDI and the proportion of binucleated cells in group 2 Gy and 0 Gy also increased, but NPB frequencies (0.023 0-0.047 0/cell) had no significant difference ( P> 0.05). MN frequencies of group 10 μg/ml were significantly lower than that of group 6 μg/ml ( U=2.74, P< 0.01). Conclusions:Cell culture time and Cyt-B concentration had no significant influence on radiation-induced NPB frequencies, suggesting that NPB could be obtained by appropriately reducing cell culture time and Cyt-B could be added into blood samples at the beginning of culture. But this protocol reduced the number of cells for further analysis, and thus its feasibility for dose estimation still need to be studied.

Objective To identify the differentially expressed microRNAs in the early transformed cells,the late transformed cells and their parental BEP2D cells.Methods The differentially expressed microRNAs in the above cells were identified by microRNAs microarray assay.Results There were 38differentially expressed microRNAs in R15H20 cells versus BEP2D cells,with 18 upregulated and 20downregulated microRNAs.R15H20 and RHT35 cells shared 25 differentially expressed microRNAs compared with BEP2D cells,with 15 down-regulated and 10 up-regulated microRNAs.There were 87differentially expressed microRNAs in RHT35 cells versus BEP2D cells,with 47 upregulated and 40 downregulated microRNAs.There were 38 differentially expressed microRNAs in RHT35 cells versus R15H20 cells with 20 upregulated and 18 downregulated microRNAs.Conclusions microRNAs are differentially expressed in the different stages of carcinogenesis of BEP2D cells induced by α particles,which suggests that microRNAs may play an important role in α particle-induced malignant transformation of BEP2D cells.