Background In the Global Burden of Disease research, it has been found that atmospheric fine particulate matter (PM_2.5) pollution significantly harms human health. Currently, there is limited research on polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) that exhibit high toxicity effects in PM_2.5 . Objective By studying the spatiotemporal distribution and variation characteristics of PCDD/Fs in PM_2.5 in Pudong area of Shanghai, to assess the associated population health risk. Methods This study set up 28 sampling points in Pudong area. One sample of PM_2.5 was collected during winter (February 2022) and summer (July 2022) at each site, with a sampling period lasting 24 h. The concentration of PM_2.5 was measured by membrane filter method, and the content of 17 kinds of 2,3,7,8-substituted chlorinated PCDD/Fs in the samples was analyzed using isotope dilution. Seasonal variations (winter and summer) in the concentrations of PM_2.5 and PCDD/Fs were evaluated, sources of PCDD/Fs pollution were tracing by principal component analysis, and health risks to the population from respiratory exposure to PCDD/Fs were estimated by VLIER-HUMAAN model. Results The PM_2.5 concentrations in the 28 samples ranged from 10 to 126 μg·m⁻³, while the concentrations of PCDD/Fs in PM_2.5 ranged from 58 to 2625 fg·m⁻³. The concentration of PM_2.5 during winter (11-126 μg·m⁻³) was higher than that during summer (10-60 μg·m⁻³). The concentration range of PCDD/Fs in winter was from 58 to 2625 fg·m⁻³, which corresponded to a range of toxic equivalent quantity (WHO-TEQ) concentration from 2.99 to 40.97 fg·m⁻³ when taking World Health Organization's toxic equivalency factor (WHO-TEQ); the concentration range of PCDD/Fs in summer was from 72 to 446 fg·m⁻³, which corresponded to a range of WHO-TEQ concentration from 2.66 to 16.61 fg·m⁻³. This range in summer was significantly lower than that observed in winter. The results of principal component analysis revealed that waste incineration was the primary source of PCDD/Fs in winter PM_2.5 in the area, whereas traffic emissions emerged as the main source in summer. The assessment of Pudong residents' respiratory exposure to PCDD/Fs in PM_2.5 showed significantly higher exposure of children in summer and winter than that of adults, indicating higher susceptibility of children to air pollutants. Both the hazard ratios (HR) for children and adults were below 1, while the cancer risks (CR) ranged from 8.41×10⁻⁸ to 2.35×10⁻⁶. Notably, during winter, the CR at 4 locations slightly exceeds 1×10⁻⁶, indicating a potential carcinogenic risk. Conclusion The overall pollution level of PCDD/Fs in PM_2.5 in Pudong area is relatively low, but it shows clear seasonal patterns. Waste incineration and traffic are the main sources of PCDD/Fs in PM_2.5 in the area. Although the cancer risk of exposure to PCDD/Fs in PM_2.5 for children or adults is relatively low, there is a certain risk at some locations in winter, necessitating additional monitoring and control.

Objective:This study aims to compare the antiviral treatment similarities and differences in the population covered by the 2024 version of the World Health Organization's (WHO) hepatitis B prevention and treatment guidelines and the current Chinese hepatitis B prevention and treatment guidelines, so as to explore their impact on the indications for antiviral therapy in Chinese patients with chronic hepatitis B (CHB).Methods:The information of patients with chronic hepatitis B virus infection who did not receive antiviral treatment was collected through the registration database of the China Clinical Research Platform for Hepatitis B Elimination. Descriptive statistics were conducted on the demographic, blood, biochemical, and virological levels of patients according to the treatment recommendations of the two versions of the guidelines. The Mann-Whitney U test and χ2 test were used to compare the differences and proportional distribution of the treatment populations covered by the two guidelines. The χ2 test was used to analyze the coverage rate of different antiviral treatment indications.Results:A total of 21,134 CHB patients without antiviral treatment were enrolled. 69.4% of patients met the 2024 versions of the WHO guidelines' recommendations. 85.0% of patients met the current Chinese hepatitis B prevention and treatment guidelines. The WHO guidelines for antiviral therapy indications were met in younger patients with higher levels of ALT, AST, and APRI scores, as well as greater proportion of patients with higher viral loads (P<0.001). The WHO guidelines recommended a cut-off value of APRI>0.5, which raised the proportion of patients on antiviral therapy from 6.6% to 30.9%. 45.7% of patients met the antiviral indications for HBV DNA >2000 IU/ml with abnormal transaminase (ALT>30 U/L for males and ALT>19 U/L for females). The reduced APRI diagnostic cut-off value and ALT treatment threshold had further increased the treatment coverage rate by 91.6% in patients with chronic HBV infection in line with the 2024 versions of WHO guidelines.Conclusion:The reduction of the APRI diagnostic cut-off value and the ALT treatment threshold, based on the current hepatitis B guidelines of China, will further improve the treatment coverage of CHB patients.

Background/Aims: Existing hepatocellular carcinoma (HCC) prediction models are derived mainly from pretreatment or early on-treatment parameters. We reassessed the dynamic changes in the performance of 17 HCC models in patients with chronic hepatitis B (CHB) during long-term antiviral therapy (AVT). Methods: Among 987 CHB patients administered long-term entecavir therapy, 660 patients had 8 years of follow-up data. Model scores were calculated using on-treatment values at 2.5, 3, 3.5, 4, 4.5, and 5 years of AVT to predict threeyear HCC occurrence. Model performance was assessed with the area under the receiver operating curve (AUROC). The original model cutoffs to distinguish different levels of HCC risk were evaluated by the log-rank test. Results: The AUROCs of the 17 HCC models varied from 0.51 to 0.78 when using on-treatment scores from years 2.5 to 5. Models with a cirrhosis variable showed numerically higher AUROCs (pooled at 0.65–0.73 for treated, untreated, or mixed treatment models) than models without (treated or mixed models: 0.61–0.68; untreated models: 0.51–0.59). Stratification into low, intermediate, and high-risk levels using the original cutoff values could no longer reflect the true HCC incidence using scores after 3.5 years of AVT for models without cirrhosis and after 4 years of AVT for models with cirrhosis. Conclusions The performance of existing HCC prediction models, especially models without the cirrhosis variable, decreased in CHB patients on long-term AVT. The optimization of existing models or the development of novel models for better HCC prediction during long-term AVT is warranted.

【Objective】 To evaluate the effect of one-beat acquisition with wide detector CT on the image quality and diagnostic efficiency of coronary CT angiography (CCTA) in patients with atrial fibrillation. 【Methods】 A total of 52 consecutive patients with atrial fibrillation, including 31 males, (67.32±11.45) years old, who underwent CCTA from July 2022 to February 2023, were analyzed retrospectively. All patients underwent one-beat acquisition CCTA. The subjective and objective image quality of the coronary arteries was evaluated, and using invasive coronary catheter angiography as the gold standard, the diagnostic efficacy of stenosis degrees above moderate and severe degrees was calculated, respectively. 【Results】 Subjective evaluation results: 92.31% (384/416) of the vascular segments were rated as excellent or good, and the diagnosable rate reached 98.08% (408/416, subjective score ≥3 points). Objective evaluation results: The CT value of the right coronary artery, anterior descending branch, and circumflex branch was (433.41±95.17)HU, (422.69±92.81)HU and (420.27±95.43)HU, respectively; the contrast-to-noise ratio was 38.46±7.54, 32.46±13.78 and 37.74±8.89, respectively. The total diagnostic accuracy, sensitivity, and specificity was 94.71%, 87.9% and 96.62%, respectively, for moderate stenosis and 96.15%, 83.64% and 98.06% for severe stenosis. 【Conclusion】 One-beat acquisition with wide detector CT can obtain high-quality coronary artery images and high diagnostic accuracy for patients with atrial fibrillation without radiation dose increase to patients. It has good clinical application value for patients with atrial fibrillation.

Objective:Our study aims to determine histological regression and clinical improvement after long-term antiviral therapy in hepatitis B virus-related cirrhosis patients.Methods:Treatment-na?ve chronic hepatitis B patients with histologically or clinically diagnosed liver cirrhosis were enrolled. Liver biopsies were performed after 5 years entecavir-based antiviral treatment. Patients were followed up every 6 months. Cirrhosis regression was evaluated based on Metavir system and P-I-R score. Clinical improvement was evaluated before and after the long-term treatment. Kruskal Wallis test and Wilcoxon signed-rank test were used for continuous variables, Fisher's exact test was used for categorical variables and multivariate analysis was performed using logistic regression analysis.Results:Totals of 73 patients with HBV-related liver cirrhosis were enrolled. Among them, 30 (41.1%) patients were biopsy proved liver cirrhosis and the remaining 43 (58.9%) cirrhotic patients were diagnosed by clinical features. Based on Metavir system and P-I-R score, 72.6% (53/73) patients attained histological regression. Furthermore, 30.1% (22/73) were defined as significant regression (Metavir decrease ≥2 stage), 42.5% (31/73) were mild regression (Metavir decrease 1 stage or predominantly regressive by P-I-R system if still cirrhosis after treatment) and 27.4% (20/73) were the non-regression. Compared to levels of clinical characteristics at baseline, HBV DNA, ALT, AST, liver stiffness(decreased from 12.7 to 6.4 kPa in significant regression, from 18.1 to 7.3 kPa in mild regression and from 21.4 to 11.2 kPa in non-regression)and Ishak-HAI score significantly decreased after 5 years of anti-HBV treatment, while serum levels of platelets and albumin improved remarkably ( P<0.05). In multivariate analysis, only the pre-treatment liver stiffness level was associated with significant regression ( OR=0.887, 95% CI: 0.802-0.981, P=0.020). Conclusions:After long-term antiviral therapy, patients with HBV-related cirrhosis are easily to attain improvements in clinical parameters, while a certain percentage of these patients still cannot achieve histological reversal.

OBJECTIVE：To investigate the clini cal features of thrombocytopenia induced by antidepressants ，and to provide reference for the rational use of clinical drugs. METHODS ：Retrieved from CNKI ，Wanfang database ，VIP，PubMed and Web of Science，during Jan. 1st in 1985 to Aug. 31st in 2020，case reports about antidepressants-induced thrombocytopenia was collected and analyzed descriptively in terms of demographic characteristics ，medication，clinical manifestations ，treatment and outcome. RESULTS：A total of 17 literatures were retrieved ，and 19 patients were included ，involving 10 male and 9 female，aged from 5 to 95 years old ，with an average of （48±24）years old. Nine kinds of drugs were involved ，including 4 cases of escitalopram ，3 cases of citalopram ，3 cases of fluoxetine ，3 cases of mirtazapine ，2 cases of amitriptyline ，1 case of sertraline ，1 case of paroxetine，1 case of mianserin and 1 case of imipramine. There were 9 cases of single drug and 10 cases of drug combination. All 19 patients suffered from thrombocytopenia at 3 d-10 years after medication ，14 of them had hemorrhage tendency. Main clinical manifestations included mucocutaneous hemorrhage ，gingival bleeding ，black stool ，hematochezia，vaginal bleeding ，ocular hemorrhage，alveolar hemorrhage. No bleeding was found in 5 cases. After drug withdrawal/changing drugs and other symptomatic treatment， platelet count of 19 patients recovered to normal ， and bleeding symptoms disappeared. CONCLUSIONS ： Thrombocytopenia caused by antidepressants has no obvious clinical features and is not easy to be found ，but it may lead to severe； bleeding symptoms if it is not found in time. The changes of platelet count should be closely monitored in clinical application of such drugs to ensure the safety of drug use.

【Objective】 To compare the enhancement effects of lean body weight （LBW） and total body weight （TBW） as indexes to calculate the contrast agent dosage under the condition of energy spectrum CT scanning. 【Methods】 A total of 218 patients who received liver enhancement CT from November 2018 to January 2019 were enrolled in this study. There were 101 patients in LBW group and 117 patients in TBW group. Both groups were scanned by energy spectrum CT， and the parameters of scanning and reconstruction were identical. The contrast agent dose was 500 mgI/kg （LBW） in LBW group and 450 mgI/kg （TBW） in TBW group， and the injection rate was 2.8 mL/s. Images were transferred to a GE AW4.7 workstation and the 50 keV monochromatic images were analyzed. We compared the dosage of contrast medium， CT value of aorta in arterial phase （HU-aorta）， hepatic enhancement CT value in venous phase （-liver）， the rate of reaching the enhancement standard and variability in the two groups. 【Results】 Compared with TBW group， LBW group had lower contrast agent dosage， HU-aorta and ∆-liver （P<0.05）， LBW and TBW group had no statistically different enhanced rate of HU-aorta as （91.09% vs. 90.60%） or ∆-liver （92.08% vs. 88.89%） （P>0.05）. The variation rate of HU-aorta and ∆-liver in LBW group was lower than that in TBW group. Using LBW as an index to calculate the dosage of liver enhanced CT also made the enhancement of liver parenchyma more consistent in different patients. 【Conclusion】 Even on the premise of energy spectrum CT scanning， using LBW-based contrast injection in liver enhanced CT can not only reduce contrast dose， but also make the enhancement in liver parenchyma more consistent among different patients.

【Objective】 To investigate the effects of 80 kVp combined with multi-model adaptive statistical iterative reconstruction algorithm （ASiR-V） on the image quality of CT angiography （CTA） of iliac artery in kidney transplantation candidates before operation. 【Methods】 Totally 50 kidney transplantation candidates underwent “one-stop” scanning combined CTA for coronary and iliac arteries were recruited consecutively. After the scanning， images were reconstructed with different ASiR-V levels on the iliac artery from 50% to 100% at a 10% interval， and 6 groups of images were obtained. We evaluated and compared all image qualities， DLP and CTDI in the patients’ examination were recorded， and the effective dose （ED） was calculated. 【Results】 All of the image quality objective scores of different ASiR-V levels on the iliac artery were above 3 points （3.32±0.24）， and the average CT value was （344.30±74.53）HU. The ED received by the patient throughout the examination was （2.71±0.42)mSv. The image noise decreased while SNR and CNR increased monotonically as the ASiR-V levels increased， among which 80% ASiR-V image quality score was the highest with 3.41±0.26. 【Conclusion】 For patients who need to have both coronary and iliac arteries evaluated before kidney transplantation operation， low tube voltage （80 kVp） combined with 80% ASiR-V can obtain high-quality iliac artery images under the premise of reducing the ED dose， which can provide practical basis for further reducing the dose in personalized scanning scheme for such patients. It has good feasibility and clinical application value.

China's CDC novel coronavirus pneumonia emergency response mechanism was announced on February 17, 2020. As of February 11, novel coronavirus had infected 3 019 medical staff (including 1 716 confirmed cases; suspected cases, clinically diagnosed cases and cases of asymptomatic infections). The reports showed that more than 80% of the patients were medical workers in general wards, which might be caused by nosocomial infection due to inadequate protection. Radiographers, who encounter patients in different departments of the hospital, also have the risk of occupational exposure to novel coronavirus pneumonia caused by strong viral infection, inadequate protection, and poor immunity. Therefore, the emergency plan is formulated for this risk in order to ensure their safety and the orderly progress of the work, provide practical basis for the future improvement and development of the emergency plan for radiographers to respond to emergent public events, and also provide ideas for peers to deal with emergencies.