Low dose radiation (LDR) is a relatively low dose, but it is important in the fields of occupational health, medical radiation protection and environmental protection. Therefore, the effects of LDR on DNA damage repair and its potential mechanisms have attracted increasing attention. LDR mainly acts on DNA molecules in direct or indirect ways, leading to DNA double strand breaks (DSBs), which then triggers DNA damage, forms cluster damage, and induces DNA damage repair, which has a potential impact on organisms. However, long-term LDR exposure may lead to dysfunction of the DNA repair system and increase the risk of accumulating DNA damage. LDR-induced DNA damage response is an adaptive response, with DNA damage repair being one of its main mechanisms. The repair of DSBs is particularly important, with the main repair methods including homologous recombination and non-homologous end joining. LDR may also trigger adaptive responses by activating immune cells, enhancing cellular antioxidant capacities, and through varies of specific biological mechanisms such as immune/inflammatory response and antioxidant responses. The biological effects of LDR mainly include cell stress response, cell cycle regulation and bystander effect. In the future, it is necessary to further explore the molecular mechanism of LDR's impact on organism health and evaluate its impact on radiation risk assessment and individualized protective measures, to better understand the basic principles of radiation biology and provide scientific basis for radiation protection, risk assessment and injury treatment.

Objective To analyze and set up the effective dose of different ionizing radiation for tunnel construction workers. Methods A total of five tunnels constructed using drilling and blasting methods were selected as the research subjects using the convenient sampling method. The workplace γ radiation effective dose, radon concentrations, and radioactive activity concentrations were detected, and on-site surveys were conducted to estimate the internal and external irradiation doses and total effective doses for workers in different work sites. Results Radiological hazards in tunnels constructed using drilling and blasting methods included radon and its progeny, γ radiation, radioactive dust (uranium-238, radium-226, thorium-232, and potassium-40) and others. The average total effective dose of ionizing radiation exposure for tunnel construction workers was (6.730 1±1.541 1) mSv. The average dose of radon and its progeny was (6.163 0±1.512 8) mSv, radioactive dust was (0.014 6±0.009 1) mSv, γ radiation was (0.552 6±0.138 7) mSv. The dose of radioactive dust of radon and its progeny was 0.24%. Radon and its progeny contributed more to the radioactive dose than radioactive dust and γ radiation (all P<0.05). Among all the radioactive dusts, the dose contribution ranked from highest to lowest was thorium-232, uranium-238, and radium-226. Conclusion For tunnel construction workers, the largest contribution to the effective dose of ionizing radiation exposure is from radon and its progeny for internal irradiation, followed by γ radiation for external irradiation. The contribution of radioactive dust to internal irradiation dose can be considered negligible.

Objectives:To explore the prognostic factors of primary central nervous system lymphoma(PCNSL) and to analyze the efficacy of different treatment methods.Methods:Clinical data of 4 812 patients with PCNSL in SEER database from January 1975 to December 2016 were retrospectively analyzed.Among them, 2 831 were male and 1 981 were female, the ratio of male to female was 1.4∶1.0.There were 2 236 cases(46.47%) under 60 years old, 1 718 cases(35.70%) aged 60 to 74 years old, and 858 cases(17.83%) aged 75 years old or above. Two thousand four hundred and seventeen cases(50.23%) had supratentorial tumors, 299 cases (6.21%) had infratentorial tumors, and 554 cases(11.51%) had multiple brain tumors, 1 542 cases (32.04%) were other or unspecified location.Three thousand five hundred and thirteen cases(73.00%) had diffuse large B-cell lymphoma (DLBCL), 234 cases(4.86%) had non DLBCL, 1 065 cases (22.13%) had other or unspecified types of tumor.The treatment included 2 011 cases (41.77%) of biopsy, 61 cases (1.27%) of subtotal resection(STR), 54 cases (1.12%) of gross total resection(GTR), 2 384 cases (49.54%) of biopsy and chemotherapy, 159 cases (3.30%) of STR and chemotherapy, 144 cases (3.00%) of GTR and chemotherapy.Univariate and multivariate Cox regression models were used to analyze the prognostic factors affecting the overall survival of the patients.Fine-Gray test and competitive risk model were used to analyze the prognostic factors affecting cancer-specific survival.Kaplan-Meier method and Log-rank test was used for survival analysis.Results:Univariate and multivariate Cox regression analyses showed that age, race, marital status, tumor site, pathological subtype, surgery, chemotherapy, combined with other malignant tumors, and HIV infection were the independent prognostic factors affecting the overall survival of PCNSL patients.The results of Fine-Gray test and competitive risk model analyses showed that age, race, marital status, tumor location, pathological subtype, surgical method, chemotherapy, combined with other malignant tumors, and HIV infection were independent prognostic factors affecting cancer-specific survival, while gender and radiotherapy had no significant correlation with cancer-specific survival.Compared with biopsy, PCNSL patients may benefit from surgical resection (STR: HR=0.805, 95% CI:0.656?0.989, P=0.04; GTR: HR=0.521, 95% CI:0.414?0.656, P<0.01).Kaplan-Meier survival analysis showed that the median survival time of biopsy+chemotherapy group was 28 months (95% CI:24.497?31.503), 2 months (95% CI:1.756?2.244) in the biopsy group, 2 months (95% CI:1.410-2.590) in the STR group, 19 months ( 95%CI:0?39.311) in the biopsy+chemotherapy group, 67 months (95% CI:46.187-87.813) in the STR+chemotherapy group, 84 months (95% CI:57.448?110.552) in the GTR+chemotherapy group.The median survival time of patients with different treatment methods was statistically significant ( P<0.01). Conclusions:Surgical resection may improve the prognosis of some PCNSL patients.Patients who have access to receive GTR or STR combined with chemotherapy may have prolonged Cancer-specific survival.

Objectives:To explore the prognostic factors of primary central nervous system lymphoma(PCNSL) and to analyze the efficacy of different treatment methods.Methods:Clinical data of 4 812 patients with PCNSL in SEER database from January 1975 to December 2016 were retrospectively analyzed.Among them, 2 831 were male and 1 981 were female, the ratio of male to female was 1.4∶1.0.There were 2 236 cases(46.47%) under 60 years old, 1 718 cases(35.70%) aged 60 to 74 years old, and 858 cases(17.83%) aged 75 years old or above. Two thousand four hundred and seventeen cases(50.23%) had supratentorial tumors, 299 cases (6.21%) had infratentorial tumors, and 554 cases(11.51%) had multiple brain tumors, 1 542 cases (32.04%) were other or unspecified location.Three thousand five hundred and thirteen cases(73.00%) had diffuse large B-cell lymphoma (DLBCL), 234 cases(4.86%) had non DLBCL, 1 065 cases (22.13%) had other or unspecified types of tumor.The treatment included 2 011 cases (41.77%) of biopsy, 61 cases (1.27%) of subtotal resection(STR), 54 cases (1.12%) of gross total resection(GTR), 2 384 cases (49.54%) of biopsy and chemotherapy, 159 cases (3.30%) of STR and chemotherapy, 144 cases (3.00%) of GTR and chemotherapy.Univariate and multivariate Cox regression models were used to analyze the prognostic factors affecting the overall survival of the patients.Fine-Gray test and competitive risk model were used to analyze the prognostic factors affecting cancer-specific survival.Kaplan-Meier method and Log-rank test was used for survival analysis.Results:Univariate and multivariate Cox regression analyses showed that age, race, marital status, tumor site, pathological subtype, surgery, chemotherapy, combined with other malignant tumors, and HIV infection were the independent prognostic factors affecting the overall survival of PCNSL patients.The results of Fine-Gray test and competitive risk model analyses showed that age, race, marital status, tumor location, pathological subtype, surgical method, chemotherapy, combined with other malignant tumors, and HIV infection were independent prognostic factors affecting cancer-specific survival, while gender and radiotherapy had no significant correlation with cancer-specific survival.Compared with biopsy, PCNSL patients may benefit from surgical resection (STR: HR=0.805, 95% CI:0.656?0.989, P=0.04; GTR: HR=0.521, 95% CI:0.414?0.656, P<0.01).Kaplan-Meier survival analysis showed that the median survival time of biopsy+chemotherapy group was 28 months (95% CI:24.497?31.503), 2 months (95% CI:1.756?2.244) in the biopsy group, 2 months (95% CI:1.410-2.590) in the STR group, 19 months ( 95%CI:0?39.311) in the biopsy+chemotherapy group, 67 months (95% CI:46.187-87.813) in the STR+chemotherapy group, 84 months (95% CI:57.448?110.552) in the GTR+chemotherapy group.The median survival time of patients with different treatment methods was statistically significant ( P<0.01). Conclusions:Surgical resection may improve the prognosis of some PCNSL patients.Patients who have access to receive GTR or STR combined with chemotherapy may have prolonged Cancer-specific survival.

Objective:To investigate the effect of long-term low dose ionizing radiation on the levels of interleukin (IL) and TGF-β1 in the population in high background radiation area(HBRA).Methods:Appropriate amount of peripheral blood was drawn from 41 and 44 healthy men aged 45-65 years who were randomly selected from Tangkou town of Yangjiang city (HBRA) and Hengpo town of Enping city (control area, CA), respectively. After centrifugation and stratification, the upper plasma of blood was separated to determine IL-2, sIL-2R, IL-4, IL-5 and TGF-β1 by using ELISA. The difference of plasma IL of the residents in those two regions was analyzed. The influence of region, age, smoking, drinking and income on the indexes of ILs and TGF-β1 was evaluated by Covariance analysis.Results:The concentration of IL-2 at HBRA area was slightly higher than those in the control area, but the other indexes were lower than those in CA residents. The differences of IL-5 ( t=7.124, P<0.001) and TGF-β1 ( t=4.900, P<0.001) between two areas were significant statistically. Covariance analysis showed that smoking had a significant effect on IL-2 level ( F=5.283, P<0.05). Conclusions:Under the influence of long-term low-dose ionizing radiation, all kinds of plasma interleukin levels of residents in HBRA were different with that in CA. The immune balance was biased towards Th1 type cytokines, and the immune function in HBRA was slightly stronger than that in CA, suggesting that long-term chronic low-dose ionizing radiation may induce adaptive changes in the immune function, which needs further study.

Glioblastoma (GBM) is the most common primary intracranial malignancy. The comprehensive treatment mode based on surgical resection has become the key to improve the prognosis of GBM and the quality of life of patients. This article reviews the progress of GBM in the fields of surgery, radiotherapy, chemotherapy, targeted therapy and immunotherapy during the past twenty years, mainly explores the similarities and differences between the treatment strategies of newly diagnosed and recurrent GBM and analyzes the difficulties in the current clinical practice of GBM.

Glioblastoma (GBM) is the most malignant primary brain tumor, and it has very poor prognosis. In recent years, the immunotherapy has become a hot issue in the treatment of malignancies. The traditional treatment regimen combined with immunotherapy might make a progress in the diagnosis and treatment of GBM. This paper reviews the explanation of the traditional chemoradiotherapy affecting the body's anti-tumor and immunity mechanism, and the current achievement of standard chemoradiotherapy combined with immunotherapy, to explore the potential benefits to GBM patients.

Objective: To analyze the treatment effect of patients with glioblastoma (GBM) and explore prognostic factors. Methods: The clinical data of 635 patients diagnosed as GBM at Neurosurgical Oncology Department Ⅳ of Beijing Tiantan Hospital, Capital Medical University from January 2007 to March 2018 were retrospectively reviewed. There were 386 males and 249 females with an age of (48.7±11.8) years (range: 18-75 years). Patients were divided into three groups according to the time of admission: 2007-2010 group(n=174), 2011-2014 group (n=237) and 2015-2018 group (n=224). Kaplan-Meier plot was used to analyze the effects of different treatment periods, treatment schemes and clinical factors on the survival of patients with GBM. Cox proportion hazard regression analysis was used to identify independent prognostic factors. Results: The median progression-free survival (PFS) and overall survival (OS) of patients in 2007-2010 group, 2011-2014 group, 2015-2018 group was 9.0 months (95% CI: 7.5-10.5), 10.0 months (95% CI: 8.8-11.2), 12.0 months (95% CI: 10.7-13.3) and 17.0 months (95% CI: 13.2-20.8), 20.0 months (95% CI: 16.9-23.1), 23.0 months(95% CI: 17.5-28.5), respectively. The PFS and OS of patients improved significantly over the years (χ²=9.693, P=0.008 and χ²=8.616, P=0.013). Multivariate survival analysis showed that age, extent of resection, radiotherapy and tumor distant dissemination were independent prognostic factors (all P<0.05). Conclusions With the continuous development of clinical treatment regimen, the therapeutic effect of Chinese GBM patients has improved remarkably. Age, extent of resection, radiotherapy and tumor distant dissemination are independent prognostic factors associated with survival time.

Objective To study the clinical significance of apolipoprotein B and apolipoprotein A1 ratio (ApoB/ApoA1) in patients with polycystic ovary syndrome (PCOS) combined metabolic syndrome (MS),by detecting the level of ApoB and ApoA1 in patients' serum.Methods 160 patients with PCOS were selected in our hospital from Jan.2014 to Dec.2015,and they were divided into MS group and non-MS group according to the diagnostic criteria of MS.The anthropometric measurements,endocrine markers,glucose and lipid metabolism indexes of patients in the two groups were measured and compared.Correlation of ApoB/ApoA 1 ratio and components of MS were analyzed,respectively.Relationship between ApoB/ApoA1 ratio and the number of abnormal components in MS were also investigated.Results Significant difference was found in the levels of ApoB ((1.01±0.34) g/L) and ApoA1((1.15±0.29) g/L) between MS group and non-MS group (P＜0.05),and ApoB/ApoA1 ratio in MS group was obviously higher than that in non-MS group (P＜0.05).ApoB/ApoAl ratio was positively correlated with BMI,waist circumference (WC),systolic blood pressure (SBP),diastolic blood pressure (DBP),fasting plasma glucose (FPG),insulin resistance index (HOMA-IR),high triglycerides (TG) and low density lipoprotein (LDL-C),respectively,and it was negatively correlated with high density lipoprotein (HDL-C)(P＜0.05).However,there was no significant correlation between ApoB/ApoA1 ratio and the age,fasting insulin (FINS),as well as the total cholesterol (TC) (P＞0.05).Moreover,ApoB/ApoA1 ratio increased with increase in the number of abnormal components (P＜0.05).Conclusion ApoB/ApoA1 ratio is closely related to the components of MS,and it may have important clinical significance for diagnosis of PCOS combined MS and preventing long-term complications of PCOS.

Objective To evaluate the clinical application value of reflectance confocal microscopy(RCM) in the diagnosis of several common diseases manifesting as papules in children, including lichen nitidus, verruca planae, lichen striatus, milium, molluscum contagiosum and lichen pilaris. Methods A total of 579 children clinically characterized by papules were recruited into this study. RCM was used to observe lesions and perilesional normal skin. The RCM features of 6 diseases manifesting as papules were analyzed and compared. Results Based on RCM images, 236 patients were diagnosed with lichen nitidus, 70 with verruca planae, 123 with lichen striatus, 40 with milium, 53 with molluscum contagiosum and 57 with lichen pilaris. All the 6 diseases had typical RCM features. Concretely speaking, RCM images of lichen nitidus lesions showed infiltration of dense inflammatory cells and melanophages in enlarged dermal papillae. In RCM images of verruca planae lesions, cells in the granular and spinous layers were arranged in concentric circles, giving a rose cluster?like appearance. RCM images of lichen striatus lesions revealed focal swelling of stratum spinosum, absent or local liquifaction degeneration of basal cells, and clustering of a moderate number of inflammatory cells in the superficial dermis. In RCM images of milium lesions, well?circumscribed round or oval structures containing highly but nonuniformly refractive materials could be seen in the dermis. RCM images of molluscum contagiosum lesions showed intact cystoid structures containing highly refractive molluscum bodies. Lowly to moderately refractive cutin ? like materials were observed along with the dilation of hair follicle infundibula in RCM images of lichen pilaris lesions. In RCM images, the 6 diseases were distinguished mainly based on structural features(patterns and refractivity)of skin lesions shown by continuous vertical scanning. Conclusion RCM is of great value to the diagnosis of diseases manifesting as papules in children.