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Objective To analyze the micronucleus rate of radiation workers and to provide accurate occupational health monitoring basis in radiation workers exposed to low-level ionizing radiation for a long time. Methods The radiation group consisted of 353 radiation workers who had been exposed to ionizing radiation during work, while the control group consisted of 41 radiation workers who had not yet been exposed to ionizing radiation before work. The cytokinesis-block micronucleus method was used to determine the micronucleus rate. Results The average micronucleus rate in the radiation group was significantly higher than that in the control group (t = −2.95, P < 0.05). In the radiation group, the micronucleus rate gradually increased with age, and the difference was statistically significant (F = 8.36, P < 0.05). The micronucleus rates of workers with > 10 and > 30 years of service were significantly higher than those of workers with < 10 years of service (χ2 = −44.79, −60.47, P < 0.05). The micronucleus rate in females was significantly higher than that in males (t = 3.93, P < 0.05). The micronucleus rates in the diagnostic radiology group and the industrial detection group were significantly higher than that in the control group (t = 3.51, 3.65, P < 0.05). Conclusion The micronucleus rate has increased among the radiation workers exposed to low-level ionizing radiation for a long time. It is necessary to further strengthen occupational health monitoring and radiation protection education for radiation workers, especially the medical workers that constitute the largest population of radiation exposure workers.
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Objective:To study the influence of circular RNA hsa_circZDHHC21_004 on the proliferation of human small intestinal epithelial cells HIEC-6 after 60Co γ-rays exposure. Methods:HIEC-6 cells were exposed to 60Co γ-rays at 0, 5, 10, and 15 Gy with a dose rate of 1 Gy/min. The expression level of hsa_circZDHHC21_004 in the irradiated HIEC-6 cell was detected. Hsa_circZDHHC21_004 was knocked-down to investigate the influences of hsa_circZDHHC21_004 on the proliferation of irradiated HIEC-6 cells by CCK-8 assay and colony formation assay. Results:The expression level of hsa_circZDHHC21_004 in HIEC-6 cells was upregulated by (1.00±0.24), (1.34±0.28), (1.85±0.31), and (2.80±0.64) times of control after 0, 5, 10, and 15 Gy irradiation, respectively and there were significant difference between 10 or 15 Gy group and 0 Gy group ( F=10.86, P=0.008). Knockdown of hsa_circZDHHC21_004 significantly increased the proliferation rate of HIEC-6 cells at 24, 48, and 72 h after 10 Gy irradiation compared with non-irradiated control ( t=-6.25, -5.83, -7.75, P < 0.001). Under 2 and 5 Gy irradiation, the clone formation rates of the hsa_circZDHHC21_004 knockdown cells were significantly higher than those of the control ( t=-7.45, -8.83, P<0.01). Conclusions:Hsa_circZDHHC21_004 is increased after irradiation and influenced the proliferation of irradiated HIEC-6 cells.
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Objective:To investigate the changes of CPT1A and CPT1B protein expression in rat intestinal epithelial cells (IEC-6) after 60Co γ-ray irradiation, and the mechanism of the influence of carnitine palmitoyltransferase 1 (CPT1) on the proliferation of irradiated IEC-6 cells. Methods:IEC-6 cells were cultured in serum-normal medium or in serum-starved medium overnight, and pretreated with 20 μmol/L palmitic acid (PA) before irradiation with 0, 5, 10, and 15 Gy. At 24 h after irradiation, the cellular protein was collected for the measurement of CPT1A and CPT1B proteins by Western blot. The influences of ETO, an inhibitor of CPT1, on the survival and proliferation of irradiated IEC-6 cells were analyzed by colony formation assay and CCK-8 assay. The protein expressions and phosphorylation levels of the extracellular signal-regulated kinase (ERK1/2) and c-Jun N-terminal kinase (JNK) in 5 Gy irradiated IEC-6 cells pre-treated with ETO were analyzed by Western blot at 48 h after radiation.Results:When IEC-6 cells were cultured in serum-normal medium together with PA, the protein level of CPT1A was significantly increased after 15 Gy irradiation ( t=-2.82, P<0.05). When IEC-6 cells were cultured in serum-starved medium, the protein level of CPT1A was significantly increased at 5, 10, and 15 Gy ( t=-3.28, -8.72, -8.67, P<0.05). When IEC-6 cells were cultured in serum-starved medium together with PA, the protein levels of CPT1A were significantly increased at 5, 10 and 15 Gy ( t=-10.69, -7.02, -8.23, P<0.05), the protein levels of CPT1B were significantly increased at 10 and 15 Gy ( t=-3.73, -5.05, P<0.05). After irradiation, the survival and proliferation of IEC-6 cells in ETO group were significantly lower than those in control group ( t=5.46, 13.22, P<0.05), and the protein level of ERK1/2 and p-JNK in ETO group were significantly lower than those in control group ( t=4.01, 3.29, 10.68, 14.44, P<0.05). Conclusions:CPT1 promoted radiation-induced IEC-6 injury cells survival and proliferation by enhancing the expression level of ERK1/2 protein and the activity of JNK.
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Objective:To explore the characteristics of lipid metabolism in rat plasma after total body irradiation(TBI) in order to provide scientific evidence of radiation biomarkers.Methods:For the non-targeted lipidomics study, 50 SD rats were divided into 6 groups and irradiated with 0, 1, 2, 3, 5 or 8 Gy 60Co γ-rays, respectively. For the targeted lipidomics study, 25 rats were divided into 5 groups and irradiated with 0, 0.5, 2.5, 4 or 6 Gy. Venous blood samples were collected and plasma were separated 4 h after TBI. Radiation-sensitive lipids were screened and their concentrations were determined. Receiver operating characteristic curve (ROC) and dose-response were analyzed. Results:A total of 15 radiation differential lipids were screened out based on non-targeted lipidomics study and 7 of them were identified as radiosensitive lipids by targeted lipidomics analysis. The ROC of radiosensitive lipids distinguished area under curve (AUC) of samples in 0 Gy group and > 0 Gy group, < 2 Gy group and ≥ 2 Gy group were all > 0.75. The AUC values were increased to 0.96 and 0.94 after the panel of radiation sensitive lipids ROC analysis. The concentrations of LysoPC(18: 2), LysoPC(22: 0), PC(18: 0/18: 2), PE(18: 2/16: 0) and PE(18: 2/18: 0) decreased with irradiation dose within 0-6 Gy.Conclusions:A total of 7 plasma radiosensitive lipids in rat plasma were identified 4 h after TBI, and the panel of them could be used for specific dose classification. Five of the lipids had good dose-response relationship.
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Objective:To investigate the metabolite changes in rat plasma after total body irradiation (TBI) and to explore dose classification based on radiation sensitive metabolites.Methods:The differential metabolites induced by radiation were screened and verified by metabolomics. In the discovery stage, 50 SD rats were irradiated with 0, 1, 2, 3, 5 and 8 Gy of 60Co γ-rays. In the verification stage, 25 rats were irradiated with 0, 0.5, 2.5, 4 and 6 Gy. Peripheral blood samples were collected 4 h after irradiation, and plasma was separated. Radiation-induced differential metabolites were identified and their concentrations were determined. Receiver operating characteristic (ROC) curve of the differential metabolites was used to classify dose range. Results:In the discovery stage, 8 radiation-induced differential metabolites in rat plasma were identified and four of them (cytosine, L-hexylcarnitine, Linoelaidylcarnitine and L-palmitylcarnitine) were upregulated, which was confirmed in the verification stage. The area under the curve (AUC) for the specific dose was >0.75. After combining these four metabolites, the AUC value to classify the radiation dose of 0 Gy versus >0 Gy, <2 Gy versus ≥2 Gy, <5 Gy versus ≥5 Gy were 0.96, 1 and 0.94, respectively.Conclusions:The metabolites in rat plasma changed significantly at 4 h after TBI, where 8 differential metabolites were identified. Cytosine, L-hexylcarnitine, linoelaidylcarnitine and L-palmiylcarnitine were stably over-expressed in the plasma after irradiation. The combination of these four compounds had high classification accuracy and thus may applicable as radiation sensitive biomarkers for dose classification.
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Objective To investigate the protective effect of CBLB 502 on radiation pneumonitis and pulmonary fibrosis for confirming the feasibility of CBLB502 as a clinical anti-radiation drug release.Methods With a single 20 Gy irradia-tion, C57BL/6J mice was sacrificed on 24 h, 1 month, 3 months and 5 months and lung tissue was assayed by TUNEL method for apoptosis of alveolar epithelial cells and endothelial cells , HE staining showing fibrosis changes , immunohisto-chemistry detecting the expression of specific indicators , as well as pathological changes of the fur and skin radiated site . Results CBLB502 inhibits apoptosis in mice alveolar epithelial cells and vascular endothelial cells after irradiation , slowing the process of pulmonary fibrosis , while reducing the expression of laminin and maintaining the expression of surfac-tant protein B, and the skin inflammation also significantly reduced .Conclusion CBLB502 could alleviate the occurrence of radiation pneumonitis and pulmonary fibrosis as well as radiation-induced skin injury .