1.Characteristics of potassium current remodeling of atrial myocytes in aged mice with atrial fibrillation
Ying DONG ; Yating CHEN ; Bin LI ; Zupei MIAO ; Qing DAN ; Xueping WANG ; Qiao XUE ; Yang LI
Chinese Journal of Pathophysiology 2025;41(10):1873-1881
AIM:To observe the changes of atrial fibrillation susceptibility,and the remodeling of atrial myo-cyte action potential,ultrarapid activation delayed rectifier potassium current(IKur)and transient outward potassium cur-rent(Ito)in elderly mice,and to explore the mechanism of atrial fibrillation from the single cell electrophysiological level.METHODS:The C57BL/6J mice were divided into old group(20 months old)and young group(4 months old).Atrial fi-brillation was induced by esophageal atrial pacing.The atrial myocytes were isolated,and action potential and ion currents were recorded with patch-clamp technique.The associated proteins were detected by Western blot technique.RE-SULTS:(1)Compared with young mice,the total incidence of atrial fibrillation was significantly increased in old mice(20.0%at 4 months old vs 60.0%at 20 months old,P<0.01).(2)The action potential duration of atrial myocytes in aged mice was shortened,and more significantly after stimulation.(3)The density of Ito and IKur in atrial myocytes of aged mice increased significantly,from(12.6±1.4)pA/pF to(21.7±1.1)pA/pF,and from(7.5±1.5)pA/pF to(13.3±2.1)pA/pF,respectively(P<0.01).After stimulation,the current increased more significantly,especially in older atrial cells.Compared with the young mice,the steady-state activation curve of Ito in the atrial myocytes of the aged mice shifted towards the depolarization,suggesting that activation of Ito channels in the aged mice increased at the same voltage stimula-tion.(4)Compared with young group,the expression of KV4.2(generating Ito)and KV1.5(generating IKur)proteins in the atrial tissue of the mice in old group was significantly increased,and the expression of caveolin-3 and end-binding protein 1(EB1)was up-regulated,suggesting that the increases in KV4.2 and KV1.5 total channel proteins and effective proteins in the cell membrane might contribute to the increase in the remodeling of potassium currents in the elderly atrial myo-cytes.CONCLUSION:The incidence of atrial fibrillation in elderly mice is significantly augmented,which may be related to the increases in Ito and IKur in atrial myocytes.The remodeling of potassium currents in elderly atrial myocytes is one of the electrophysiological bases leading to the shortening of action potential duration and the occurrence of atrial fibrillation.
2.Effect of HSYA on LCN2-induced iron death of HT22 cells and its mechanism based on SLC7A11/GPX4 signaling pathway
Meng-wei RONG ; Cun-yan DAN ; Tian-qing XIA ; Yi YANG ; Xiu LOU ; Chen-xiang JI ; Bao-guo XIAO ; Cun-gen MA ; Li-juan SONG
Chinese Pharmacological Bulletin 2025;41(11):2097-2105
Aim To explore the effect of hydroxysafflor yellow A(HSYA)on lipocalin 2(LCN2)-induced fer-roptosis in HT22 cells and the related mechanism.Methods Thirty male Sprague-Dawley(SD)rats were used to establish the middle cerebral artery occlu-sion/reperfusion(MCAO/R)model by the suture method.The rats were randomly divided into the Sham group,the MCAO/R group,and the MCAO/R+HSYA group.The infarct area was measured by TTC staining,and the degree of neurological deficit was evaluated by the Z-Longa scoring method.The expressions of LCN2 and 24P3R in brain tissues were detected by Western blot.LCN2 protein was added to HT-22 cells,and the cells were divided into the normal group,the LCN2 group,and the LCN2+HSYA group.The optimal con-centration of LCN2-induced neuronal ferroptosis was screened by LDH assay and Western blot,and the ex-pression levels of ferritin,FPN1,GPX4,SLC7A11,COX2,and 24P3R were detected.LCN2 was knocked down by siRNA transfection,and the expressions of GPX4 and ferritin were detected.The contents of glu-tathione(GSH),malondialdehyde(MDA),GPX4,and Fe2+were determined by colorimetry,and the expres-sion of GPX4 was detected by immunofluorescence.The binding force between HSYA and LCN2 was ana-lyzed by molecular docking technology.Results Ani-mal experiments showed that HSYA could reduce the cerebral infarction area and decrease the neurological function score of MCAO/R rats.Compared with the sham group,the levels of LCN2 and 24P3R increased in the MCAO/R group,while HSYA inhibited their ex-pressions.Cell experiments showed that the optimal concentration of LCN2 to induce ferroptosis in HT22 cells was 2 μmol·L-1.After knocking down LCN2 by siRNA transfection,compared with the LCN2 group,the expression levels of GPX4 and ferritin in the siLCN2 group increased significantly.Compared with the nor-mal group,the expressions of SLC7A11,GPX4,FPN1,ferritin,and GSH in the LCN2 group decreased signifi-cantly,while the concentration of Fe2+,and the expres-sions of MDA,COX2,and 24P3R increased.HSYA could increase the expressions of SLC7A11,GPX4,FPN1,ferritin,and GSH,reduce the contents of Fe2+and MDA,and inhibit the expressions of COX2 and 24P3R.Molecular docking showed that the binding en-ergy between HSYA and LCN2 was-8.0 kJ·mol-1.Conclusion HSYA can inhibit LCN2-induced ferrop-tosis in HT22 cells through the SLC7A11/GPX4 signa-ling pathway.
3.Impact of Polygonum cuspidatum and polydatin on lipid deposition in adipose tissue of obese mice
Bi-lin XU ; Lu-guang SHENG ; Dan-dan LIU ; Wei-bin LIU ; Tao LEI ; Qing-guang CHEN ; Hao LU
Chinese Traditional Patent Medicine 2025;47(9):2912-2917
AIM To investigate the effects of Polygonum cuspidatum and polydatin on lipid deposition in adipose tissue of high-fat diet-induced obese mice.METHODS Forty male C57BL/6J mice were randomly assigned to either a control group(10 mice)fed standard chow or a diet-induced obesity(DIO)group(30 mice)fed a high-fat diet for 8 weeks.The successful mouse models were randomly assigned to the model group,the polydatin group(250 mg/kg)and the P.cuspidatum group(4.5 g/kg),with 8 mice in each group,to resume their high-fat diet during the following 8 weeks corresponding drug administration by gavage.Weekly body weight measurements were recorded for all mice.Serum TG,TC and LDL levels were quantified post-treatment.Histopathological assessment of adipose tissue was performed using HE staining.The mRNA expressions of AMPK,SREBP-1c and FAS in adipose tissue were analyzed by RT-qPCR.The protein expressions of p-AMPK,SREBP-1c and FAS in adipose tissue was detected by Western blot.RESULTS Compared to the control group,the model group displayed significantly higher body weight,inguinal fat weight and epididymal fat weight(P<0.05);elevated serum TG,TC and LDL levels(P<0.05);markedly enlarged volumes of inguinal and epididymal adipocytes(P<0.01);reduced p-AMPK protein expression in inguinal adipose tissue(P<0.01);and upregulated mRNA and protein expressions of SREBP-1c and FAS(P<0.05,P<0.01).Compared to the model group,both the P.cuspidatum group and polygonin group exhibited significantly reduced body weight and inguinal fat weight(P<0.05);decreased serum TG and TC levels(P<0.05);reduced inguinal adipocyte size(P<0.01);elevated p-AMPK protein expression in inguinal adipose tissue(P<0.01);and downregulated mRNA and protein expressions of SREBP-1c and FAS(P<0.05,P<0.01).CONCLUSION P.cuspidatum and polydatin significantly increases p-AMPK expression while decreasing SREBP-1c and FAS levels in adipose tissue.This regulatory effect likely contributes to reduction of body weight in obese mice through suppression of lipogenesis.
4.Neurokinin 1 receptor inhibition alleviated mitochondrial dysfunction via restoring purine nucleotide cycle disorder driven by substance P in acute pancreatitis.
Chenxia HAN ; Lu LI ; Lin BAI ; Yaling WU ; Jiawang LI ; Yiqin WANG ; Wanmeng LI ; Xue REN ; Ping LIAO ; Xiaoting CHEN ; Yaguang ZHANG ; Fengzhi WU ; Feng LI ; Dan DU ; Qing XIA
Acta Pharmaceutica Sinica B 2025;15(6):3025-3040
Acute pancreatitis (AP) is a life-threatening gastrointestinal disorder for which no effective pharmacological treatments are currently available. One of the pharmacological targets that merits further research is the neurokinin 1 receptor (NK1R), which is found on pancreatic acinar cells and responds to the neuropeptide substance P (SP) that participates in AP. Although a few studies have stated the involvement of SP/NK1R in neurogenic inflammation in AP development, the regulatory mechanism remains unclear. In this study, we found that following activation of NK1R by SP, β-arrestin1, a scaffold protein of NK1R, down-regulated transcription of Adss, Adsl, and Ampd in the purine nucleotide cycle, thereby inhibiting mitochondrial function through fumarate depletion. Interestingly, we identified magnolol as a new and natural NK1R inhibitor with a non-nitrogenous biphenyl core structure. It exhibited a beneficial effect on AP by restoring purine nucleotide cycle metabolic enzymes and fumarate levels. Our study not only provides new therapeutic strategies, leading compounds, and drug translation possibilities for AP, but also provides important clues for the study of downstream mechanisms driven by SP in other diseases.
5.Coverage of National Immunization Program vaccines and vaccination information consistency rate among children born during 2020-2021 in 3 provinces in China
Wenqi HUANG ; Miao XU ; Xiaohua QI ; Qing WANG ; Jing CHEN ; Ming GUANG ; Yu LIU ; Xu CHEN ; Fangfang ZENG ; Dan LIU ; Xiaofeng LIANG
Chinese Journal of Epidemiology 2025;46(8):1393-1399
Objective:To understand the coverage and information consistency rate of National Immunization Program (NIP) vaccines among children born during 2020-2021 in Zhejiang Province, Chongqing City, and Shanxi Province (3 provinces) of China .Methods:A simple random sampling method was used to randomly select 3 counties (districts) from each of the 3 provinces, 5 townships from each county (district), and 5 villages from each township. Vaccination information for seven NIP vaccines was collected for children born between 2020 and 2021 in each village. The vaccination coverage, timely coverage, and consistency rates between the survey data and the Immunization Planning Information System data were analyzed.Results:A total of 1 117 children were investigated. The vaccination coverage for each dose of NIP vaccine ranged from 99.10% to 100.00%, with those in Zhejiang Province, Chongqing City, and Shanxi Province ranging from 99.19% to 100.00%, 98.92% to 100.00%, and 99.20% to 100.00%, respectively. The timely coverage of each dose of NIP vaccine ranged from 89.79% to 99.82%, with those in Zhejiang Province, Chongqing City, and Shanxi Province ranging from 94.09% to 99.73%, 89.52% to 99.73%, and 78.55% to 100.00%, respectively. The consistency rate of information on each dose of NIP vaccine ranged from 94.36% to 99.91%, with those in Zhejiang Province, Chongqing City, and Shanxi Province ranging from 97.85% to 99.73%, 98.92% to 100.00%, and 86.06% to 100.00%, respectively.Conclusions:Coverage of NIP vaccines was generally high among children born during 2020-2021 in the 3 provinces of China, but there were regional differences in the timely coverage of some vaccine doses and the vaccination information consistency rate. It is necessary to strengthen the timely vaccination of children's vaccine booster doses and optimize the management of vaccination services.
6.Feasibility and exploration of optimal communication models for robot-assisted urological telesurgery: a multicenter, single-arm, retrospective study
Ye WANG ; Taoping SHI ; Sheng TAI ; Sunyi YE ; Yubai ZHANG ; Bingzhang QIAO ; Chenfeng WANG ; Gen CHENG ; Zhi LI ; Qing AI ; Qingbo HUANG ; Baojun WANG ; Qing YUAN ; Junnan XU ; Guojun LIU ; Yu CHEN ; Wuyi ZHAO ; Jianle MAO ; Shiwei LI ; Shuo WANG ; Dan XIA ; Wanhai XU ; Chaozhao LIANG ; Hongzhao LI ; Xin MA ; Xu ZHANG
Chinese Journal of Urology 2025;46(5):331-336
Objective:To evaluate the efficacy and feasibility of a domestically developed robotic surgical system based on fiber-optic dedicated line communication in cross-regional urological telesurgery.Methods:This was multicenter,single-arm,retrospective case series study. The data of patients who underwent urological telesurgeries using the telesurgical system between January 2023 and December 2024 were analyzed. The cohort included 59 patients from seven hospitals across China. Among the patients,47 were male(79.7%)and 12 were female(20.3%),with a median age of 63.0(56.0,68.0)years and a body mass index of(24.7 ± 3.0)kg/m 2. Surgical procedures included 32 radical prostatectomies,24 partial nephrectomies,one radical nephrectomy,one adrenalectomy,and one ureteral reconstruction. The perioperative indicators,pathological results and postoperative complications were analyzed. The network monitoring data were collected,and the perioperative data of patients,remote system monitoring data and costs were compared between the two communication modes of optical transport network(OTN)and cloud-connect network(CCN). Results:All 59 remote surgeries were successfully completed,with a mean operative time of(138.0 ± 54.0)minutes,median intraoperative blood loss of 50.0(30.0,100.0)ml and a postoperative hospital stay of 5.0(4.0,6.0)days. No cases required reoperation,Clavien-Dindo grade ≥3 complications,or readmission. The geographical distance between the primary and remote surgical sites ranged from 450 to 2 800 km. Network monitoring revealed increased bidirectional latency with distance increasing:the shortest latency time(Hefei-Hangzhou,450 km)was(16.59 ± 0.80)ms,while the longest(Harbin-Hangzhou,2 200 km)latency time was(53.31 ± 0.31)ms. Average frame loss per procedure was 0?1.27 frames. The results of subgroup analysis comparing OTN and CCN communication modes showed no significant differences in operative time[(130.7 ± 70.5)minutes vs.(142.1 ± 42.9)minutes, P = 0.442],postoperative hospitalization[6.0(4.0,8.0)d vs. 5.0(4.0,6.0)d, P = 0.581],or readmission rates(0 vs. 0). However,CCN demonstrated significant cost advantages with 500 RMB per operation vs. 3 000 RMB per operation for OTN. Conclusions:Urological telesurgery using fiber-optic communication is feasible. The CCN mode,with its cost-effectiveness,excellent usability,and multi-point interconnection flexibility,is currently the preferred communication model for telesurgical applications.
7.Coverage of National Immunization Program vaccines and vaccination information consistency rate among children born during 2020-2021 in 3 provinces in China
Wenqi HUANG ; Miao XU ; Xiaohua QI ; Qing WANG ; Jing CHEN ; Ming GUANG ; Yu LIU ; Xu CHEN ; Fangfang ZENG ; Dan LIU ; Xiaofeng LIANG
Chinese Journal of Epidemiology 2025;46(8):1393-1399
Objective:To understand the coverage and information consistency rate of National Immunization Program (NIP) vaccines among children born during 2020-2021 in Zhejiang Province, Chongqing City, and Shanxi Province (3 provinces) of China .Methods:A simple random sampling method was used to randomly select 3 counties (districts) from each of the 3 provinces, 5 townships from each county (district), and 5 villages from each township. Vaccination information for seven NIP vaccines was collected for children born between 2020 and 2021 in each village. The vaccination coverage, timely coverage, and consistency rates between the survey data and the Immunization Planning Information System data were analyzed.Results:A total of 1 117 children were investigated. The vaccination coverage for each dose of NIP vaccine ranged from 99.10% to 100.00%, with those in Zhejiang Province, Chongqing City, and Shanxi Province ranging from 99.19% to 100.00%, 98.92% to 100.00%, and 99.20% to 100.00%, respectively. The timely coverage of each dose of NIP vaccine ranged from 89.79% to 99.82%, with those in Zhejiang Province, Chongqing City, and Shanxi Province ranging from 94.09% to 99.73%, 89.52% to 99.73%, and 78.55% to 100.00%, respectively. The consistency rate of information on each dose of NIP vaccine ranged from 94.36% to 99.91%, with those in Zhejiang Province, Chongqing City, and Shanxi Province ranging from 97.85% to 99.73%, 98.92% to 100.00%, and 86.06% to 100.00%, respectively.Conclusions:Coverage of NIP vaccines was generally high among children born during 2020-2021 in the 3 provinces of China, but there were regional differences in the timely coverage of some vaccine doses and the vaccination information consistency rate. It is necessary to strengthen the timely vaccination of children's vaccine booster doses and optimize the management of vaccination services.
8.Analysis of clinical characteristics of patients with chronic obstructive pulmonary disease complicated by anorexia
Dan PENG ; Tao LI ; Ping ZHANG ; Cong LIU ; Ling LIN ; Yuqin ZENG ; Ping CHEN ; Qing SONG
Journal of Chinese Physician 2025;27(6):809-814
Objective:To analyze the clinical characteristics of patients with chronic obstructive pulmonary disease (COPD) complicated by anorexia.Methods:This cross-sectional study included patients registered in the RealDTC study from May 2023 to December 2023. Demographic data, COPD Assessment Test (CAT) score, modified Medical Research Council (mMRC) dyspnea questionnaire score, Clinical COPD Questionnaire (CCQ) score, forced expiratory volume in one second (FEV 1), forced expiratory volume in the first second predicted of percentage (FEV 1%pred), FEV 1/forced vital capacity (FVC), Global Initiative for Chronic Obstructive Lung Disease (GOLD) grade, GOLD group, number of acute exacerbations and hospitalizations in the past year, and score of the Functional Assessment of Anorexia Cachexia Therapy-Anorexia/Cachexia Subscale-12 (FAACT-A/CS-12) were collected. Patients with a FAACT-A/CS-12 score ≤30 were diagnosed as having anorexia. Multivariate logistic regression analysis was used to evaluate the influencing factors of anorexia in COPD patients. Results:A total of 617 COPD patients were included, of whom 109(17.7%) had anorexia. Compared with non-anorexia patients, COPD patients with anorexia had higher age, CAT, mMRC and CCQ scores, and more acute exacerbations and hospitalizations in the past year, while body mass index, FEV 1, FEV 1%pred and FEV 1/FVC were lower (all P<0.05). The proportions of patients with primary education or below, GOLD 3-4 grade and GOLD E group were higher in COPD patients with anorexia (all P<0.05). Logistic regression analysis showed that a CAT score of 10-<20 [odds ratio ( OR)=4.017, 95% confidence interval ( CI): 1.673-59.645], a CAT score of 20-<30 ( OR=9.686, 95% CI: 3.777-24.842), a CAT score of ≥30 ( OR=78.286, 95% CI: 7.654-800.689) and ≥1 hospitalization in the past year ( OR=2.050, 95% CI: 1.292-3.254) were independent risk factors for anorexia in COPD patients (all P<0.05). Conclusions:COPD patients with anorexia have poor lung function, high symptom burden and high risk of acute exacerbation. Clinicians should pay attention to the management of COPD patients with anorexia and take corresponding intervention measures.
9.Effects of combined use of active ingredients in Buyang Huanwu Decoction on oxygen-glucose deprivation/reglucose-reoxygenation-induced inflammation and oxidative stress of BV2 cells.
Tian-Qing XIA ; Ying CHEN ; Jian-Lin HUA ; Qin SU ; Cun-Yan DAN ; Meng-Wei RONG ; Shi-Ning GE ; Hong GUO ; Bao-Guo XIAO ; Jie-Zhong YU ; Cun-Gen MA ; Li-Juan SONG
China Journal of Chinese Materia Medica 2025;50(14):3835-3846
This study aims to explore the effects and action mechanisms of the active ingredients in Buyang Huanwu Decoction(BYHWD), namely tetramethylpyrazine(TMP) and hydroxy-safflor yellow A(HSYA), on oxygen-glucose deprivation/reglucose-reoxygenation(OGD/R)-induced inflammation and oxidative stress of microglia(MG). Network pharmacology was used to screen the effective monomer ingredients of BYHWD and determine the safe concentration range for each component. Inflammation and oxidative stress models were established to further screen the best ingredient combination and optimal concentration ratio with the most effective anti-inflammatory and antioxidant effects. OGD/R BV2 cell models were constructed, and BV2 cells in the logarithmic growth phase were divided into a normal group, a model group, an HSYA group, a TMP group, and an HSYA + TMP group. Enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of inflammatory cytokines such as interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), and interleukin-6(IL-6). Oxidative stress markers, including superoxide dismutase(SOD), nitric oxide(NO), and malondialdehyde(MDA), were also measured. Western blot was used to analyze the protein expression of both inflammation-related pathway [Toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB)] and oxidative stress-related pathway [nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)]. Immunofluorescence was used to assess the expression of proteins such as inducible nitric oxide synthase(iNOS) and arginase-1(Arg-1). The most effective ingredients for anti-inflammatory and antioxidant effects in BYHWD were TMP and HSYA. Compared to the normal group, the model group showed significantly increased levels of IL-1β, TNF-α, IL-6, NO, and MDA, along with significantly higher protein expression of NF-κB, TLR4, Nrf2, and HO-1 and significantly lower SOD levels. The differences between the two groups were statistically significant. Compared to the model group, both the HSYA group and the TMP group showed significantly reduced levels of IL-1β, TNF-α, IL-6, NO, and MDA, lower expression of NF-κB and TLR4 proteins, higher levels of SOD, and significantly increased protein expression of Nrf2 and HO-1. Additionally, the expression of the M1-type MG marker iNOS was significantly reduced, while the expression of the M2-type MG marker Arg-1 was significantly increased. The results of the HSYA group and the TMP group had statistically significant differences from those of the model group. Compared to the HSYA group and the TMP group, the HSYA + TMP group showed further significant reductions in IL-1β, TNF-α, IL-6, NO, and MDA levels, along with significant reductions in NF-κB and TLR4 protein expression, an increase in SOD levels, and elevated Nrf2 and HO-1 protein expression. Additionally, the expression of the M1-type MG marker iNOS was reduced, while the M2-type MG marker Arg-1 expression increased significantly in the HSYA + TMP group compared to the TMP or HSYA group. The differences in the results were statistically significant between the HSYA + TMP group and the TMP or HSYA group. The findings indicated that the combined use of HSYA and TMP, the active ingredients of BYHWD, can effectively inhibit OGD/R-induced inflammation and oxidative stress of MG, showing superior effects compared to the individual use of either component.
Oxidative Stress/drug effects*
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Drugs, Chinese Herbal/pharmacology*
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Animals
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Mice
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Glucose/metabolism*
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Cell Line
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Inflammation/genetics*
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Oxygen/metabolism*
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Pyrazines/pharmacology*
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Microglia/metabolism*
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NF-E2-Related Factor 2/immunology*
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NF-kappa B/immunology*
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Toll-Like Receptor 4/immunology*
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Anti-Inflammatory Agents/pharmacology*
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Humans
10.Investigation on the gross α and gross β activity levels of drinking water around Zhangzhou Nuclear Power Plant
Mengmeng LIU ; Jianxi ZHA ; Jia LIU ; Qishan ZHENG ; Senxing ZHENG ; Dan LIN ; Yunhua QING ; Yan ZHANG ; Jianbo CHEN ; Lihua HUANG
Chinese Journal of Radiological Health 2025;34(5):648-653
Objective To investigate the levels of gross α and gross β activities in different water types within a 40-kilometer radius around the Zhangzhou Nuclear Power Plant prior to its operation. Methods In 2018, drinking water samples were collected from the area surrounding the nuclear power plant during both the wet and dry seasons, including source water, treated water, tap water, and well water. The gross α and gross β activity concentrations were measured using a low-background α/β counter, followed by statistical analysis. Results A total of 80 water samples from different sources around the Zhangzhou Nuclear Power Plant were collected. The average gross α and gross β activity concentrations during the wet season were (0.110 ± 0.036) Bq/L and (0.643 ± 0.028) Bq/L, respectively, while those during the dry season were (0.124 ± 0.032) Bq/L and (0.624 ± 0.026) Bq/L, respectively. There were no significant differences in the gross α and gross β activity concentrations between the wet and dry seasons for the overall sample set (P > 0.05). However, there were statistically significant differences in the gross α and gross β activity concentrations between the wet and dry seasons for source water and well water (Zwet = −2.005, −2.123; Zdry = −1.943, −3.090; P < 0.05). Conclusion The radioactivity levels in different water types within various ranges around the Zhangzhou Nuclear Power Plant before its operation were determined. The measured activity concentrations were at the same level as those from previous investigations in other regions of Fujian Province.

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