1.Local thermal effect of RF on nanogold-labeled RNase
Jiancai ZHAI ; Jianping SHI ; Kimberly Hamad Chifferli ; Shuguang ZHANG ;
Journal of Third Military Medical University 2003;0(08):-
Objective To establish a biological model with nanostructure and to investigate the characteristics of the thermal conduction by radio frequency electromagnetic radiation upon the model for the exploration of the possible mechanism of microwave non thermal effect. Methods The prepared nanogold labeled RNase S sample was analyzed by routine hydrolytic ability of poly c and CD spectroscopy. After confirmation of the successful recombination of the enzymatic structure and the recovery of the enzyme activity, thermal effects of RF on the sample, water and air were compared. Results The biological model designed and prepared by us satisfactorily simulated the native RNase A in both recovery of enzyme activity and conformation. Air sample in air bathing possessed an exponent decreasing function for thermal dispersion and an exponent increasing function for RF thermal effect. The redistilled water sample had a linear increasing function for RF thermal effect. Meanwhile, nanogold labeled RNase S in water bathing kept constant for RF thermal effect. Conclusion Micro eddy current local heating might occur in microstructure consisting of nanometal cluster. A biological macromolecule with nanostructure, acting as a source of thermal radiation and conduction, might resonantly interact with some changeable domains nearby, so the biological model keeps isothermal during RF heating. This may be a possible mechanism of nonthermal effect for microwave and other physical factors.
3.Research advances in innate immunity mechanism of nonalcoholic fatty liver disease
Qingqing ZHAI ; Zhenhua ZHOU ; Weijian WANG
Journal of Clinical Hepatology 2015;31(7):1147-1152
The pathogenesis and progression of nonalcoholic fatty liver disease (NAFLD) are closely associated with the activation of the innate immune system. This article reviews how various types of immune cells, Toll-like receptors, and their downstream signaling pathways are involved in insulin resistance and mediate oxidative stress, inflammation, and fibrosis in the liver. Reduction or elimination of dendritic cells delays inflammatory responses and fibrosis in the liver. A decrease in natural killer T cells induces lipid accumulation at the stage of simple steatosis, but alleviates fibrosis at the inflammation stage. The mTOR signaling pathways for insulin and amino acids suppresses autophagy through short-term or long-term regulation, which leads to endoplasmic reticulum stress and altered insulin resistance, thereby modulating the development and progression of NAFLD. The research on the mechanisms by which traditional Chinese medicine offers therapeutic benefits for NAFLD increasingly focuses on the potential role of immunity.
4.Investigation on present state of radiation protection of a 60Co irradiation facility
Hongfang WANG ; Zechen FENG ; Huan WANG ; Bin BAI ; Shuguang ZHAI ; Yongzhong MA
Chinese Journal of Radiological Medicine and Protection 2023;43(3):204-208
Objective:To explore the present state of radiation protection in an operational large-sized irradiation facility and the distribution of incurred radiation doses in the controlled area under abnormal conditions, and to analyze the acompanied radiation risk.Methods:With an irradiation facility in operation as the research object, the radiation doses were measured using AT1121 X and gamma dose rate meters for the soruce both in working and storage. Thermoluminescent dosimeters (TLDs) were used to measure the dose distribution in an irradiation field under abnormal conditions. The radiation safety features were checked against the several relevant national standards, with the radiation risks evaluated.Results:The radiation dose rates were in the range of 0.09-0.11 μSv/h, lower than the environmental background level whether in storage or working. Under abnormal working conditions, the radiation dose values from high to low were 1.0-101.3 Sv, 32.7-514.0 mSv and 8.7-183.2 μSv in the irradiation field, respectively. At the outside maze, the doses were close to the background level.Conclusions:The protection features of the irradiation facility meet the requirements of the relevant national standards. Under abnormal conditions, radiation could cause serious damages to the persons staying in the irradiation field. These persons were suggested to access to maze as soon as possible to reduce the exposure time, and activate the emergency protection equipments to deescalate the 60Co source onto the well.
5.Autologous whole blood injections to patients with chronic spontaneous urticaria and positive autologous serum skin test: an efficacy evaluation
Shuguang CHEN ; Zhifang ZHAI ; Zhiqiang SONG ; Lin FENG ; Xiuying HUANG ; Xiaofang ZHOU ; Yi YOU ; Hua ZHONG ; Huan WANG ; Liangjin CHENG ; Mingming XIANG ; Fei HAO
Chinese Journal of Dermatology 2012;45(7):470-473
[Objective] To evaluate the efficacy of autologous whole blood injections in patients with chronic spontaneous urticaria and positive autologous serum skin test (ASST).[[Methods]] After assessment of clinical history,patients with chronic spontaneous urticaria underwent skin prick test (SPT) and ASST.Then,100 patients with positive ASST but negative SPT for common allergens were randomly classified into treatment group (n =60) and control group (n =40).Oral loratadine was given to all the patients with a gradual tapering to the least maintenance dose.Patients in the treatment group were also injected with autologous whole blood once a week for 12 times.Patients were evaluated by urticaria activity score (UAS) and dermatology life quality index (DLQI) at the baseline,the end of the 3rd and 6th month after the initial treatment.The total amount of antihistamines required for the control of urticaria every month was calculated.The UAS,DLQI,accumulative amount of administrated antihistamines,and the diameter of wheal/flush induced by autologous serum were compared by t test before and after the treatment,and the efficacy was compared by rank sum test between the two groups.[Results] No significant difference was observed between the control and treatment group in UAS at the baseline (5.73 ± 0.51 vs.5.32 ± 0.79,P> 0.05).The UAS reached 1.57 ± 1.42 and 0.69± 0.92 with a decrease rate of 69% and 81% in the treatment group,and 3.65 ± 1.53 and 2.65 ± 1.61 with a decrease rate of 35% and 53% in the control group,respectively at the end of the 3rd and 6th month,and statistical difference was observed for the decrease in both groups at the two time points (all P < 0.05).The total amount of antihistamines required for the control of urticaria per month averaged 8.63 pills and 3.83 pills respectively in the treatment group after 3 and 6 months of treatment,significantly less than that in the control group (16.85 and 15.27 pills,respectively).[Conclusion]s The combination of oral antihistamine and autologous whole blood injections can not only reduce disease activity and improve patients' quality of life,but also decrease the total amount of antihistamines required for the control of urticaria.
6.Application of endoscopic ultrasound in tumor staging of adenocarcinoma of the esophagogastric junction after neoadjuvant therapy
Tao PENG ; Huibin GAO ; Zhan LOU ; Shuguang LI ; Xiaoyong ZHAI
Cancer Research and Clinic 2022;34(11):826-830
Objective:To investigate the application value of endoscopic ultrasound (EUS) in tumor staging of adenocarcinoma of the esophagogastric junction (AEG) after neoadjuvant concurrent chemoradiotherapy.Methods:The clinical data of 40 patients diagnosed with stage Ⅲ AEG and treated with neoadjuvant concurrent chemoradiotherapy from January 2016 to December 2021 in the First Affiliated Hospital of Hebei North University were retrospectively analyzed. EUS was used to perform preoperative tumor staging after neoadjuvant concurrent chemoradiotherapy to evaluate the therapeutic effect, and the consistency between EUS and postoperative pathological staging was analyzed.Results:In 40 AEG patients after neoadjuvant chemoradiotherapy, the EUS staging was stage yp-uT 2 in 12 cases, stage yp-uT 3 in 18 cases, and stage yp-uT 4 in 10 cases. The postoperative pathological staging was stage pT 1 in 2 cases, stage pT 2 in 14 cases, stage pT 3 in 12 cases, and stage pT 4 in 12 cases. Taking postoperative pathological results as the gold standard, the accuracy of EUS for T staging after neoadjuvant chemoradiotherapy was 62.5%, and the accuracy, sensitivity and specificity for stage T 2 were 58.3%, 50.0% and 80.8%, respectively. The accuracy, sensitivity and specificity for stage T 3 were 61.1%, 91.7% and 75.0%, respectively. The accuracy, sensitivity and specificity for stage T 4 were 70.0%, 58.3% and 89.3%, respectively. The Kappa value of the consistency test between yp-uT staging and pT staging was 0.453. The EUS staging of lymph nodes was stage yp-uN 0 in 15 cases, stage yp-uN 1 in 10 cases, stage yp-uN 2 in 10 cases, and stage yp-uN 3 in 5 cases. The postoperative pathological staging was stage pN 0 in 18 cases, stage pN 1 in 7 cases, stage pN 2 in 7 cases, and stage pN 3 in 8 cases. Taking postoperative pathological results as the gold standard, the accuracy rate of EUS for N staging after neoadjuvant chemoradiotherapy was 57.5%, and the accuracy, sensitivity and specificity of EUS for stage N 0 were 73.3%, 61.1% and 81.8%, respectively. The accuracy, sensitivity and specificity for stage N 1 were 50.0%, 71.4% and 84.8%, respectively. The accuracy, sensitivity and specificity for stage N 2 were 40.0%, 57.1% and 81.8%, respectively. The accuracy, sensitivity and specificity for stage N 3 were 60.0%, 37.5% and 93.8%, respectively. The Kappa value of the consistency test between yp-uN staging and pN staging was 0.409. Conclusions:EUS is not accurate for T staging in patients with stage Ⅲ AEG after neoadjuvant therapy, but has high sensitivity for stage T 3 and high specificity for stage T 4. EUS has low sensitivity for N staging in patients with stage Ⅲ AEG after neoadjuvant therapy, but has high specificity for stage N 3.
7.Monitoring and analysis of activity concentrations of 7Be and 210Pb in atmospheric aerosol in Beijing from 2017 to 2020
Huan WANG ; Qinghua MENG ; Yongzhong MA ; Yun LOU ; Bin BAI ; Weijie ZHU ; Yuxia KONG ; Hongfang WANG ; Hong ZHANG ; Zechen FENG ; Shuguang ZHAI ; Jun YU
Chinese Journal of Radiological Medicine and Protection 2021;41(9):690-694
Objective:To monitor and analyze the activity concentrations of 7Be and 210Pb in atmospheric aerosol in Beijing from 2017 to 2020. Methods:Totally 1 074 atmospheric aerosol samples were collected by high flow air sampler (SnowWhite) including 275 in spring, 266 in summer, 262 in autumn and 271 in winter and subjected to analysis by low background high-purity germanium gamma-ray spectrometery (ORTEC) to determine the activity concentrations of 7Be and 210Pb. Results:The activity concentrations of 7Be in atmospheric aerosol were from 0.56 to 14.84 mBq/m 3, with an avearage of 6.84 mBq/m 3, and from 0.01 to 9.37 mBq/m 3 for 210Pb, with an avearage 3.19 mBq/m 3. The differences in activity concentrations of 7Be and 210Pb in atmospheric aerosol among differernt seasons were statistically significant ( F=32.66, 93.93, P<0.05). Activity concentration of 7Be was highest in spring, followed by autumn, and lowest in summer and winter. Activity concentration of 210Pb ranged from winter, autumn, spring to summer in descending order. Conclusions:The activity concentrations of 7Be and 210Pb in atmospheric aerosol in Beijing from 2017 to 2020 fluctated within the range of normal level.
8.Analysis on the distribution status and concentration degree of radiological diagnosis and treatment resources in Beijing
Shuguang ZHAI ; Zechen FENG ; Jun YU ; Weijie ZHU ; Jun HAN ; Lin SONG ; Zhibin ZHANG ; Bin BAI
Chinese Journal of Radiological Health 2021;30(4):412-416
Objective To analyze the distribution status and agglomeration degree of radiological diagnosis and treatment resources in Beijing, and provide references for rationally coordinating the allocation of radiological diagnosis and treatment resources, formulating resource allocation policies, and promoting the stable development and efficient use of radiological diagnosis and treatment resources. Methods Based on the medical radiation protection monitoring data of Beijing medical and health institutions from 2019 to 2020, the current situation of radiological diagnosis and treatment resources is described by the number of radiological diagnosis and treatment resources, the average service volume, and the resource composition, and the distribution of radiological diagnosis and treatment resources in Beijing is evaluated with the aid of the agglomeration degree. Results The number of radiological diagnostic equipment, the number of service personnel, and the number of radiological workers engaged in third-level hospitals is the largest; for the number of service personnel for each type of single equipment, third-level hospitals account for a larger proportion, and radiotherapy and nuclear medicine services are concentrated in third-level hospitals. Human resource pressure and equipment service pressure are relatively high in third-level hospitals. First-level hospitals mainly undertake radiological diagnosis services. There is little difference in the amount of radiological diagnosis services per capita between second-level hospitals and third-level hospitals. Nuclear medicine and radiotherapy in third-level hospitals per capita service volume is significantly higher than that insecond-level hospitals. Radiological diagnosis and radiotherapy resources are concentrated in urban areas to a large extent. Conclusion There are obvious differences in the utilization of radiological diagnosis and treatment resources in different levels of hospitals. There is a significant concentration of radiological diagnosis and treatment resources in various districts. There is a certain degree of unbalanced distribution and inadequate utilization of radiological diagnosis and treatment resources in Beijing.
9.Variation of 137Cs activity concentration in aerosol in Beijing
Huan WANG ; Qinghua MENG ; Yun LOU ; Bin BAI ; Weijie ZHU ; Hongfang WANG ; Yuxia KONG ; Zechen FENG ; Shuguang ZHAI ; Jun YU ; Yaru SUN ; Yongzhong MA
Journal of Environmental and Occupational Medicine 2024;41(9):1038-1042
Background 137Cs in atmospheric aerosol is the product of past nuclear weapon tests and nuclear accidents. When 137Cs is released into the atmosphere, it will deposit in dry land and marine environment, causing pollution of soil surface, water, agricultural products, and animal byproducts, and affecting public health. Objective To identify the variation pattern of 137Cs activity concentration in aerosol and its correlation with dust concentration in Beijing area from 2017 to 2020. Methods A total of 958 aerosol samples were collected from November 1, 2017 to June 30, 2020 in Beijing with a high volume air sampler at a sampling flow rate about 600 m3·h−1 and a collection time for each sample about 24 h. The activity concentration of 137Cs in the aerosol samples was determined with a low-background high-purity germanium γ spectrometer. The dust concentration was calculated using the difference in the mass of the aerosol filter before and after sampling. The detection rate of 137Cs and dust concentration in different seasons were compared. Spearman rank correlation test was used to analyze the correlation between 137Cs activity concentration and dust concentration. Results From 2017 to 2020, the 137Cs activity concentrations of 33 from 958 aerosol samples in Beijing were above the minimum detectable activityconcentration, the overall detection rate of 137Cs was 3.4%, and the activity concentration ranged from 1.86 to 45.53 μBq·m−3, with a median value of 4.85 μBq·m−3. The detection rate of 137Cs was highest in spring, followed by autumn, and lowest in winter and summer (8.4%, 3.0%, 1.1%, and 0.5%, respectively). The dust concentration ranged from 0.03 to 1.55 mg·m−3, with an average value of 0.18 mg·m−3. There was a statistically significant difference in the dust concentrations in spring, summer, autumn, and winter (F=45.51, P<0.05), and the highest value was 0.24 mg·m−3 in spring (P<0.05). The 137Cs activity concentration was positively correlated with the dust concentration (P<0.05). Conclusion The 137Cs activity concentration in aerosol in Beijing from 2017 to 2020 fluctuates within the range of background level, and its activity concentration is highest in spring, followed autumn, and lowest in summer and winter.