[Research on the formulation and revision of radiological parameters in the "Standards for Drinking Water Quality（GB5749-2022）" in China]

The radioactive safety of drinking water has attracted increasing public concern. The newly issued Standards for Drinking Water Quality (GB5749-2022) in China has revised the radiological parameters. This article provides an overview of the main sources, levels of radionuclides in drinking water, and summarized the individual doses criterion and adverse health effects associated with exposure of the public to radionuclides from drinking-water. It analyzes and discusses the relevant revision content of radiological parameters, including the guidance values for screening gross α and gross β, subtracting the contribution of potassium-40 from gross β activity when the gross β activity concentration exceeds the screening level, and the basis for establishing the limit values of reference indices uranium and radium-226. Specific implementation and evaluation suggestions are also proposed.

[Evaluation of peripheral blood T-lymphocyte subpopulations features in patients with hepatitis B virus-related acute-on-chronic liver failure based on single-cell sequencing technology]

Objective: T lymphocyte exhaustion is an important component of immune dysfunction. Therefore, exploring peripheral blood-exhausted T lymphocyte features in patients with hepatitis B virus-related acute-on-chronic liver failure may provide potential therapeutic target molecules for ACLF immune dysfunction. Methods: Six cases with HBV-ACLF and three healthy controls were selected for T-cell heterogeneity detection using the single-cell RNA sequencing method. In addition, exhausted T lymphocyte subpopulations were screened to analyze their gene expression features, and their developmental trajectories quasi-timing. An independent sample t-test was used to compare the samples between the two groups. Results: Peripheral blood T lymphocytes in HBV-ACLF patients had different differentiation trajectories with different features distinct into eight subpopulations. Among them, the CD4(+)TIGIT(+) subsets (P = 0.007) and CD8(+)LAG3(+) (P = 0.010) subsets with highly exhausted genes were significantly higher than those in healthy controls. Quasi-time analysis showed that CD4(+)TIGIT(+) and CD8(+)LAG3(+) subsets appeared in the late stage of T lymphocyte differentiation, suggesting the transition of T lymphocyte from naïve-effector-exhausted during ACLF pathogenesis. Conclusion: There is heterogeneity in peripheral blood T lymphocyte differentiation in patients with HBV-ACLF, and the number of exhausted T cells featured by CD4(+)TIGIT(+)T cell and CD8(+)LAG3(+) T cell subsets increases significantly, suggesting that T lymphocyte immune exhaustion is involved in the immune dysfunction of HBV-ACLF, thereby identifying potential effective target molecules for improving ACLF patients' immune function.

Serum sclerostin as a potential novel biomarker for heart valve calcification in patients with chronic kidney disease

OBJECTIVE

To explore the correlation between change in sclerostin level and heart valve calcification in patients with chronic kidney disease (CKD) in stages 3-5, as well as the possible underlying mechanism, which could provide a clinical reference for the diagnosis and treatment of cardiovascular disease (CVD).

PATIENTS AND METHODS

110 patients were divided into a healthy control group and three groups of patients with CKD stages 3, 4, and 5 according to CKD staging guidelines. Scr, BUN, AKP, TC, TG, HDL, LDL, Ca, Pi, and CRP were measured, and calcium-phosphate product (Ca×Pi) calculated. ELISA was used to measure the sclerostin level, and the estimated glomerular filtration rate (eGFR) was calculated by MDRD. Heart valve calcification was measured by a physician in the Cardiac Department of our hospital. The correlations between sclerostin-level change and heart valve calcification, as well as each index in CKD patients in stages 3-5, were analyzed.

RESULTS

Compared with the healthy control group, the serum Ca in CKD stage-3, stage-4, and stage-5 groups (p < 0.05) was reduced, and PTH was increased (p < 0.05). Blood Pi and Ca×Pi in the stage-4 and stage-5 groups were increased (p < 0.05). The serum sclerostin level increased with renal hypofunction in stage-3 CKD patients, and was significantly increased compared with that of the control group, reaching the highest level in the terminal stage (p < 0.01). Pearson correlation analysis indicated that serum sclerostin was negatively correlated with eGFR (r = -0.91, p < 0.001) and blood Ca (r= -0.271, p < 0.001), and positively correlated with SCr (r = 0.608, p < 0.001), blood Pi level (r = 0.295, p < 0.001), PTH (r = 0.334, p < 0.001), and Ca×Pi (r = 0.275, p < 0.001). The rate of heart valve calcification in the CKD patients in stage 5 was relatively high (11/30, 36.67%), and significantly higher than that in healthy controls (1/20, 5%; p < 0.01). Logistic regression analysis of heart valve calcification indicated that sclerostin was a risk factor for heart valve calcification in CKD patients in stages 3-5.

CONCLUSIONS

The sclerostin level gradually increased with renal hypofunction in CKD patients in stages 3-5, and the increase in serum sclerostin level in the CKD patients occurred earlier than the change in Pi and Ca×Pi. The risk of heart valve calcification in stage-5 CKD patients was significantly increased. Sclerostin is an independent risk factor for heart valve calcification in CKD patients.

Diazoxide induces endoplasmic reticulum stress-related neuroprotection mediated by p38 MAPK against Aβ25-35 insults

OBJECTIVE

The endoplasmic reticulum (ER) -resident caspase-12 was identified as a mediator of Aβ neurotoxicity. Recent evidence indicates that mitochondrial ATP-sensitive potassium (KATP) channel openers mediate their neuroprotective role by adjusting ER stress pathways, but the molecular details remain largely unknown and have been investigated.

MATERIALS AND METHODS

In this study, the protein expression levels of calreticulin (CRT) and caspase-12 activation and phosphorylated p38 MAPK were observed by immunoblotting in cultured PC12 cells from different groups: treatment with Aβ25-35 (group Aβ25-35), treatment with diazoxide (group diazoxide), pretreatment with diazoxide and then exposure to Aβ25-35 (group diazoxide + Aβ25-35), pretreatment with p38 MAPK inhibitor SB 203580 and then exposure to diazoxide and Aβ25-35 (group SB 203580 + diazoxide + Aβ25-35), and the control (group control).

RESULTS

In response to the treatment with Aβ25-35 (10 µM) for 24 h, the protein expression levels of CRT and caspase-12 activation were increased and phosphorylated p38 MAPK was decreased significantly. Diazoxide reduced CRT overexpression and caspase-12 activation and increased the up-regulation of phosphorylated p38 MAPK. When SB 203580 was presented before exposure to diazoxide and Aβ25-35, CRT expression was markedly suppressed, and the inhibition effect of diazoxide on caspase-12 activation was almost eliminated.

CONCLUSIONS

We showed that diazoxide induced ERS-related neuroprotection mediated by p38 MAPK against Aβ25-35 insults. From the clinical point of view, these results are of considerable importance for the understanding of AD pathogenesis. However, further studies are required to explore more detailed mechanisms of the observed effects.

[Factors associated with fatigue in the employees of internet companies]

Objective: To explore factors associated with fatigue in employees working in Internet companies. Methods: A cross-sectional study was conducted among 3603 employees from 35 internet companies. A self-conducted questionnaire was used to assess employees' fatigue and related factors. Results: The scores of body fatigue, mental fatigue and total fatigue were (4.53±2.56) , (2.37±1.64) , and (6.90±3.55) respectively. The body fatigue is positively correlated with job burnout and musculoskeletal disorders (r=0.426, 0.485) ; the mental fatigue is positively correlated with job burnout (r=0.429) . JDC and ERI occupational stress, burnout and high level of musculoskeletal disorders increased the risk of body fatigue of which odds ratios are 1.58, 1.72, 4.08 and 5.91; odds ratios for the risk of mental fatigue are 1.73, 1.37, 2.61 and 2.08. Sleep time over 7 hours reduces the risk of fatigue (P<0.05) with odds ratio of 0.61 and 0.62. Conclusion: Employees of Internet companies is facing fatigue issues. To protect employee's physical and mental health is highly important for employers to alleviate fatigue and improve work performance.

[Protective effect of picroside Ⅱ on the brain tissue through antioxidation in stroke rats]

Objective: To investigate the effect and mechanisms of picroside Ⅱ on the brain tissue after cerebral ischemia reperfusion(I/R) in rats. Methods: The middle cerebral artery occlusion(MCAO) rat model was established by inserting a monofilament into middle cerebral artery. The experimental rats were treated by injecting picroside Ⅱ intraperitoneally. The modified neurological severity score (mNSS) and body weight were determined before modeling and after reperfusion of 22 h. The cerebral infarct volume was measured by TTC staining and the cerebral water content was measured in rats. At the same time, ROS content and NADPH oxidase activity were detected. The structure of neurons was observed by electron microscope and the mRNA and protein levels of Rac-1 and Nox2 were detected by RT-PCR and Western blotting. Results: After modeling, the mNSS score was significantly increased (12.6±1.3 vs 0, P<0.001), while the body weight was lost (13.3%±2.5% vs 4.9%±0.8%, P<0.01). The cerebral infarct volume increased obviously (33.5%±3.4% vs 0, P<0.001), brain water content increased significantly (81.5%±0.9% vs 77.7%±0.9%, P<0.05) and the structure of neuron was damaged obviously. The protein and mRNA levels of Rac-1 and Nox2 were significantly increased (P<0.05). After treatment with picroside Ⅱ, mNSS score decreased significantly (7.9±0.8 vs 12.6±1.3, P<0.05) and the body weight increased obviously (9.3%±1.1% vs 13.3%±2.5%, P<0.05). The infarct volume of brain was significantly reduced (18.2%±1.9% vs 33.5%±3.4%, P<0.05), brain water content decreased obviously (79.1%±0.7% vs 81.5±0.9%, P<0.05), the morphological structures of neurons was restored, and the expressions of Rac-1 and Nox2 were significantly decreased (P<0.05). Conclusion: It is suggested that picroside Ⅱ could exert antioxidation to protect the brain tissue through inhibiting the expression of Rac-1 and Nox2.

[Association of occupational stress with job burnout and depression tendency in workers in Internet companies]

Objective: To investigate the association of occupational stress with job burnout and depression tendency in workers in Internet companies. Methods: From July to November, 2016, the cross-sectional method was used to perform a questionnaire survey of 3603 workers in 35 Internet companies in Beijing, Shandong Province, and Zhejiang Province in China, and the association of occupational stress with job burnout and depression tendency was analyzed. Results: Among these workers, 63.70% had occupational stress with job demand-control (JDC) and 34.60% had occupational stress with effort-reward imbalance (ERI) ; among the workers engaged in sales, 75.63% had occupational stress with JDC and 62.70% had occupational stress with ERI. Of all workers, 10.69% had job burnout, and among the workers engaged in sales, 22.12% had job burnout. Of all workers, 18.79% had the tendency of moderate-to-severe or severe depression, and among the workers engaged in sales, 46.13% had such tendency. Occupational stress with JDC increased the risk of job burnout and depression (odds ratio[OR]=3.52 and 1.85, P<0.05) , and occupational stress with ERI also increased the risk of job burnout and depression (OR=8.24 and 5.59, P<0.05) . In addition, irregular diet and insomnia were risk factors for job burnout; age ≥41 years, low income, sales position, working time spent on the screen ≥10 hours/day, insomnia, and poor self-evaluated health status were risk factors for depression tendency. Conclusion: Occupational stress with JDC and ERI increases the risk of job burnout and depression tendency, and among the workers in Internet companies, the workers engaged in sales have the most severe occupational stress, job burnout, and depression tendency.

Robust generation of entangled state via ground-state antiblockade of Rydberg atoms

We propose a mechanism of ground-state antiblockade of Rydberg atoms, which is then exploited to prepare two-atom entangled state via three different kinds of pulses. First we use the pulses in the form of sin2 and cos2 functions and obtain a maximally entangled state at an accurate interaction time. Then the method of stimulated Raman adiabatic passage (STIRAP) is adopted for the entanglement generation, which is immune to the fluctuations of revelent parameters but requires a long time. Finally we capitalize the advantages of the former two methods and employ shortcuts to adiabatic passage (STAP) to generate the maximal entanglement. The strictly numerical simulation reveals that the current scheme is robust against spontaneous emission of atoms due to the virtual excitation of Rydberg states, and all of the above methods favor a high fidelity with the present experimental technology.

[Study of neuron-protective effect and mechanism of neuregulin1β against cerebral ischemia reperfusion-induced injury in rats]

Objective: Thecurrent study is to explore the neuron-protective mechanism of neuregulin1β (NRG1β) in a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) through inhibiting the c-Jun phosphorylation. Methods: After 24 h of MCAO/R (referring to Longa's method), neurobehavioral function was measured by modified neurological severity score (mNSS) test; the cerebral infarction volume was detected by triphenyltetrazolium chloride (TTC) staining; the blood brain barrier (BBB) permeability was measured by Evans Blue (EB); the neuron morphology of brain tissue was observed by Nissl stain; the ultra-structures of the neurons were observed by transmission electron microscopy (TEM); the apoptotic neurons were counted by in situ cell death detection kit colocalized with NeuN; the expressions of phospho-c-Jun was determined by immunofluorescent labeling and Western blot analysis. Results: Compared with the sham-operation rats, the rats receiving MCAO/R showed increased mNSS (9.7±1.2), cerebral infarction volume (41.4±3.0)%, permeability of BBB, deformation of neurons, ischemia-induced apoptosis (0.63±0.04), and enhanced expression of phospho-c-Jun protein (0.90±0.07) (all P<0.05). Our data indicated that NRG1β attenuated neurologic deficits (6.4±0.9), decreased the cerebral infarction volume (10.4±0.5), reduced EB extravasation (1.55±0.13) and the deformation of neurons, protected the ultra-structure of neurons, blocked ischemia-induced apoptosis (0.23±0.02), through down-regulated phospho-c-Jun expression (0.40±0.03) in MCAO/R rats (P<0.05). Conclusion: NRG1β exerts neuron-protective effects against ischemia reperfusion-induced injury in rats through inhibiting the c-Jun phosphorylation.

Conversion of entangled states with nitrogen-vacancy centers coupled to microtoroidal resonators

We propose efficient schemes for converting three-photon, four-photon and five-photon GHZ state to a W state or Dicke state, respectively with the nitrogen-vacancy (N-V) centers via single-photon input-output process and cross-Kerr nonlinearities. The total success probability can be improved by iterating the conversion process for the case of three-photon and five-photon while it does not require iteration for converting four-photon GHZ state to a W state. The analysis of feasibility shows that our scheme is feasible for current experimental technology.

Fusing atomic W states via quantum Zeno dynamics

We propose a scheme for preparation of large-scale entangled W states based on the fusion mechanism via quantum Zeno dynamics. By sending two atoms belonging to an n-atom W state and an m-atom W state, respectively, into a vacuum cavity (or two separate cavities), we may obtain a (n + m - 2)-atom W state via detecting the two-atom state after interaction. The present scheme is robust against both spontaneous emission of atoms and decay of cavity, and the feasibility analysis indicates that it can also be realized in experiment.

[Occupational stress in assembly line workers in electronics manufacturing service and related influencing factors]

Objective: To investigate occupational stress in assembly line workers in electronics manu-facturing service (EMS) and related influencing factors. Methods: From June to October, 2015, a cross-sectional survey was performed for 5 944 assembly line workers in EMS (observation group) and 6 270 workers from other posts (non-assembly line workers and management personnel; control group) using the self-made questionnaire for basic information, job demand-control (JDC) model questionnaire, and effort-reward imbalance (ERI) model questionnaire to collect respondents' basic information and occupational stress. Results: The observation group had significantly lower work autonomy, social support, and work reward scores than the control group (2.72 ± 0.63/3.64 ± 0.68/4.06 ± 0.80 vs 3.00 ± 0.67/3.83 ± 0.68/4.24 ± 0.75, t=23.53, 15.41, and 12.70, all P<0.05) , as well as significantly higher work effort and job involvement scores than the control group (2.34±0.78/2.48±0.78 vs 2.21±0.80/2.33±0.77, t=-9.08 and-10.90, both P<0.05). The observation group had significantly higher proportions of workers with occupational stress determined by JDC and ERI models than the control group (64.5%/12.7% vs 52.6%/9.9%, χ²=182.26 and 23.41, both P<0.05). Female sex, migrant workers, working time >60 hours/week, and sleeping time <7 hours/day were major risk factors for occupational stress in JDC model; education background of Bachelor's degree or above, working time >60 hours/week, and sleeping time<7 hours/day were major risk factors for occupational stress in ERI model, while female sex and a high monthly income reduced the risk of occupational stress in ERI model. Conclusion: Assembly line workers in EMS are a relatively vulnerable group and have a high degree of occupational stress. Working time >60 hours/week and sleeping time <7 hours/day are major risk factors for occupational stress.

[Occupational stress and early health effects in migrant workers in an electronics manufacturing service enterprise]

Objective: To investigate occupational stress in migrant workers in an electronics manufacturing service enterprise and the association between occupational stress and early health effects, such as job burnout, depressive tendency, and insomnia. Methods: In August 2015, stratified random cluster sampling was used to select 1 097 migrant workers in an electronics manufacturing service enterprise. The Job Demand-Autonomy Questionnaire and effort-reward imbalance questionnaire were used to investigate occupational stress with the types of high workload and effort-reward imbalance, and Burnout Inventory, depression scale, and self-management sleep questionnaire were used to investigate the early health effects of occupational stress. Results: In these migrant workers, the detection rates of occupational stress with the types of high workload and effort-reward imbalance were 69.8%(766/1 097) and 11.9%(131/1 097). The multivariate logistic regression analysis showed that the workers who had occupational stress with the types of high workload and effort-reward imbalance had significantly higher risks of job burnout and depressive tendencies than those who did not have these two types of occupational stress (P<0.01). The workers who had occupational stress with the type of effort-reward imbalance had a significantly higher ability to predict the risks of job burnout and depressive tendencies than those who had occupational stress with the type of high workload (P<0.01) , as well as a significantly higher risk of insomnia than those who did not have this type of occupational stress (P<0.01). Conclusion: Occupational stress is the major influencing factor for early health effects, such as job burnout, depressive tendency, and insomnia, in the migrant workers in this electronics manufacturing service enterprise. The workers who have occupational stress with the type of effort-reward imbalance have higher risks of job burnout and depressive tendencies than those who have occupational stress with the type of high workload.

[Analysis of correlation between pulmonary function and expression levels of matrix metalloproteinases-9 and tissue inhibitor of metalloproteinase-1 among toluene diisocyanate exposed workers]

OBJECTIVE

To investigate the effect of occupational toluene diisocyanate(TDI) exposure on matrix metalloproteinases-9 (MMP-9) and tissue inhibitor of metalloproteinase-1(TIMP-1), and analysis of the correlation of MMP-9,TIMP-1,MMP-9/TIMP-1 and lung function.

METHODS

In October 2014, based on cluster sampling, we conducted a cross-sectional study in a TDI production factory located in China's western region. 61 exposed workers were recruited from workers engaged in packing, operating and checking. Based on different levels of the external exposure, the packers were classified as high exposed group, while operators and checkers as low exposed group. 58 factory managers, matching age and agent, were selected as controls, having same work intense and not contacting the TDI or other allergens. The questionnaire surveys were used to obtain the agent, age, work age, smoking and drinking, personal and family allergic history, occupational history, and the recent health conditions. The levels of MMP-9 and TIMP-1 in serum of subjects were determind by ELISA. The time weighted average concentrations (8h-TWA) were used to describe the levels of TDI air exposure in working environment. Spearman correlation assay was used to investigate the correlation of MMP-9, TIMP-1, MMP-9/TIMP-1 and lung function, exposure time.

RESULTS

8-hour TWA means of TDI air levels in exposed group, packers, operators and checkers were 0.39, 0.76, 0.25 mg/m(3), respectively . According to the external exposure concentration, the packers were classified as high exposed group, and the operators and checkers were classified as low exposed group. In controls, low exposed group and high exposed group, the levels of MMP-9, respectively, were (807.21±347.70),(586.91±317.50),(388.94±312.01) ng/ml (χ(2)=16.69, P<0.001), respectively, and the P50(P25-P75) of MMP-9/TIMP-1 were 4.67(2.87-6.68), 2.3(1.44-3.48), 1.11(0.59-1.48) (χ(2)=39.42, P<0.001), respectively, and the concentrations of TIMP-1, were (173.44±72.67), (236.12±51.98), (302.81±44.39) ng/ml (F=20.09, P< 0.001), respectively. The levels P50(P25-P75) of FVC, FEV1.0 and FEV1.0/FVC in exposed group were, 92.8% (86.0%-101.8%), 85.5%(76.7%-92.8%), 112.5(108.2-118.5), respectively, which were lower than that in control group (124.3%(107.9%-144.2%), 142.7%(119.1%-155.7%), 129.2(123.5-134))(Z values were 7.70, 8.97, 8.62, and all P<0.001). Spearman rank correlation analysis showed that levels of MMP-9 were positively associated with FEV1.0, and FEV1.0/FVC (r values were 0.27, 0.25, respectively, all P<0.05), and The levels of TIMP-1 were negatively associated with FVC, FEV1.0, and FEV1.0/FVC (r valuse were -0.33, -0.39, -0.39, all P<0.05).The levels of MMP-9 were negatively correlated with exposure time(r=-0.26, P=0.040). The positive correlations of MMP-9/TIMP-1 with FVC, FEV1.0, and FEV1.0/FVC were also found (r valuse were 0.34, 0.44, 0.40, all P<0.05).

CONCLUSION

TDI exposure could induce the downs of MMP-9 and MMP-9/TIMP-1 associated with lung functions. The MMP-9 and MMP-9/TIMP-1,in a way, could reflect the respiratory inflammatory injury caused by TDI exposure.

Determination of traces of 237Np in environmental samples by ICP-MS after separation using TOA extraction chromatography

A simple, rapid, cost-efficient, and robust method for separation of 237Np with an extraction chromatographic column (TOA: tri-n-octylamine on Teflon powder) is outlined in detail and further improved for direct ICP-MS analysis. The column efficiently retained 237Np in 2 mol L(-1) HNO3 medium and all of the 237Np was easily eluted with 0.02 mol L(-1) oxalic acid in 0.16 mol L(-1) HNO3 at 95 degrees C. The separated solutions were free from most matrix elements and were aspirated into the ICP-MS directly. The decontamination factor for 238U is more than 10(4). The instrumental detection limit for 237Np was 0.46 pg mL(-1), which corresponds to 1.2 x 10(-5) Bq mL(-1). The method is more rapid than traditional radiometric techniques. It is also considered to be more suitable for environmental monitoring than existing methods based on TOA.