Objective To track and evaluate the implementation and application of the occupational health standard Radiation shielding requirements for radiotherapy room—Part 4: Radiotherapy room of ²⁵²Cf neutron afterloading (GBZ/T 201.4-2015) by radiation health technical service agencies, medical institutions, health supervision agencies, and radiotherapy facility design units, and to provide a scientific basis for the further revision and implementation of this standard. Methods Following the Guideline for health standards tracking evaluation (WS/T 536-2017) and the project implementation plan, relevant practitioners were randomly selected for a questionnaire survey. The survey primarily focused on their awareness, standard training, application, and revision suggestions of GBZ/T 201.4-2015. The results were summarized and analyzed. Results A total of 168 evaluation questionnaires were collected from relevant practitioners in 28 provinces. Only 31.6% of the respondents reported being “well familiar” or “ familiar” with the standard, 27.4% of the respondents believed that the standard was widely used, and 45.2% of the respondents believed that the standard could meet the needs of their work. Only 14.9% of the respondents had received relevant training on the standard, more than half of the respondents had not applied the standard within the past 10 years, and 45.2% of the respondents believed that the standard "needs to be revised". Conclusion Due to the small number of californium-252 neutron afterloading radiotherapy devices in operation on the market, the overall awareness of the standard is low, suggesting that relevant authorities need to strengthen training and publicity of the standard, and that certain sections of the standard need to be revised or merged.

Objective To analyze the risk factors associated with early recurrence after surgery for concomitant exo-tropia and establish a Nomogram prediction model.Methods A retrospective analysis was conducted on 243 cases(486 eyes)of concomitant exotropia treated in the Ophthalmology Department of our hospital from October 2015 to October 2021.The patients were divided into a training set(n=170)and a validation set(n=73)at a ratio of 7∶3.The Lasso re-gression,Boruta algorithm,and random forest algorithm were used to screen risk variables related to postoperative recur-rence of concomitant exotropia.The Spearman correlation analysis and variance inflation factor(VIF)were used to assess collinearity among variables,and a Nomogram prediction model was established using multivariate Cox regression.The re-ceiver operating characteristic curve,calibration curve,and clinical decision curve of the model at 6 months,18 months,and 24 months after surgery were used to assess the efficacy of the model.Results Three machine learning methods in-cluding Lasso regression,Boruta algorithm,and random forest algorithm identified six significant variables that might con-tribute to early recurrence after strabismus surgery from 22 risk variables in both training and validation sets.No collineari-ty was found among the six variables(r＜0.6,VIF＜5).Multivariate Cox regression revealed that strabismus type(inter-mittent exotropia),preoperative strabismus angle,best-corrected visual acuity(BCVA)in the right eye,BCVA in both eyes,and surgical procedures(unilateral lateral rectus recession)were risk factors for early recurrence after surgery for concomitant exotropia.Meanwhile,a Nomogram prediction model was constructed based on these 6 factors.The receiver operating characteristic,calibration,and clinical decision curves indicated that the prediction model had good accuracy,consistency,and clinical applicability.Conclusion Nomogram prediction model can effectively predict the risk of early recurrence after surgery for concomitant exotropia,and provides a reference for ophthalmologists to intervene early in pa-tients.

Objective To analyze the changing trend of the disease burden of age-related macular degeneration(AMD)in China from 1990 to 2021 and the impact of age,period,and cohort effects,and to predict the standardized prev-alence and disability-adjusted life year(DALY)rate of AMD in China from 2022 to 2035.Methods The data on the preva-lence of AMD,the number of AMD patients,DALYs,and DALY rates in China from 1990 to 2021 were obtained from the Global Burden of Disease(GBD 2021).The segmented regression model was used to analyze the trend changes in the prev-alence and DALY of patients with AMD in China,the age-period-cohort(APC)model was employed to estimate the age,period,and cohort effects related to the prevalence risk and DALY risk of AMD,and the Bayesian age-period cohort model was used to analyze the standardized prevalence and DALY rate of AMD in China from 2022 to 2035.Results Compared with 1990,the number of AMD patients and the prevalence of this disease in China in 2021 increased by 199.94％and 148.02％,respectively,and the DALYs and DALY rate increased by 183.95％and 134.80％,respectively,with the higher value of relevant indicators observed in females compared with males.From 1990 to 2021,the standardized prevalence of AMD in China showed an increasing trend,with the average annual percentage change(AAPC)being 0.17％.In contrast,the standardized DALY rate of AMD showed a decreasing trend,with the AAPC being-0.03％.The results of the age-peri-od-cohort model showed that the longitudinal age curves for both the prevalence and DALY rate of AMD in China showed an increasing and then decreasing trend,peaking at 85-89 years of age.Over time,the prevalence risk of AMD increased and then decreased,while the DALY risk continued to decline.The birth cohort analysis results showed that the overall fluctua-tion of the AMD prevalence risk cohort effect in China was small,with a decline first and then a fluctuating increase.Mean-while,the DALY risk gradually decreased as the birth cohort moved backward.It can be predicted that both the standard-ized prevalence and the standardized DALY rate of AMD may present an upward trend in China from 2022 to 2035.Conclu-sion From 1990 to 2021,the standardized prevalence of AMD in China displays an upward trend,while its standardized DALY rate exhibits a downward trend.Notably,the disease burden is more pronounced in the female population compared with the male population.With the continued aging of the population,it can be predicted that both the standardized preva-lence and DALY rate of AMD will escalate from 2022 to 2035.This finding underscores the need for targeted interventions,particularly for elderly women.Meanwhile,it is necessary to enhance health education for the whole population and formu-late effective public health policies to alleviate the disease burden associated with AMD in China.

Objective To analyze the risk factors associated with early recurrence after surgery for concomitant exo-tropia and establish a Nomogram prediction model.Methods A retrospective analysis was conducted on 243 cases(486 eyes)of concomitant exotropia treated in the Ophthalmology Department of our hospital from October 2015 to October 2021.The patients were divided into a training set(n=170)and a validation set(n=73)at a ratio of 7∶3.The Lasso re-gression,Boruta algorithm,and random forest algorithm were used to screen risk variables related to postoperative recur-rence of concomitant exotropia.The Spearman correlation analysis and variance inflation factor(VIF)were used to assess collinearity among variables,and a Nomogram prediction model was established using multivariate Cox regression.The re-ceiver operating characteristic curve,calibration curve,and clinical decision curve of the model at 6 months,18 months,and 24 months after surgery were used to assess the efficacy of the model.Results Three machine learning methods in-cluding Lasso regression,Boruta algorithm,and random forest algorithm identified six significant variables that might con-tribute to early recurrence after strabismus surgery from 22 risk variables in both training and validation sets.No collineari-ty was found among the six variables(r＜0.6,VIF＜5).Multivariate Cox regression revealed that strabismus type(inter-mittent exotropia),preoperative strabismus angle,best-corrected visual acuity(BCVA)in the right eye,BCVA in both eyes,and surgical procedures(unilateral lateral rectus recession)were risk factors for early recurrence after surgery for concomitant exotropia.Meanwhile,a Nomogram prediction model was constructed based on these 6 factors.The receiver operating characteristic,calibration,and clinical decision curves indicated that the prediction model had good accuracy,consistency,and clinical applicability.Conclusion Nomogram prediction model can effectively predict the risk of early recurrence after surgery for concomitant exotropia,and provides a reference for ophthalmologists to intervene early in pa-tients.

Objective To analyze the changing trend of the disease burden of age-related macular degeneration(AMD)in China from 1990 to 2021 and the impact of age,period,and cohort effects,and to predict the standardized prev-alence and disability-adjusted life year(DALY)rate of AMD in China from 2022 to 2035.Methods The data on the preva-lence of AMD,the number of AMD patients,DALYs,and DALY rates in China from 1990 to 2021 were obtained from the Global Burden of Disease(GBD 2021).The segmented regression model was used to analyze the trend changes in the prev-alence and DALY of patients with AMD in China,the age-period-cohort(APC)model was employed to estimate the age,period,and cohort effects related to the prevalence risk and DALY risk of AMD,and the Bayesian age-period cohort model was used to analyze the standardized prevalence and DALY rate of AMD in China from 2022 to 2035.Results Compared with 1990,the number of AMD patients and the prevalence of this disease in China in 2021 increased by 199.94％and 148.02％,respectively,and the DALYs and DALY rate increased by 183.95％and 134.80％,respectively,with the higher value of relevant indicators observed in females compared with males.From 1990 to 2021,the standardized prevalence of AMD in China showed an increasing trend,with the average annual percentage change(AAPC)being 0.17％.In contrast,the standardized DALY rate of AMD showed a decreasing trend,with the AAPC being-0.03％.The results of the age-peri-od-cohort model showed that the longitudinal age curves for both the prevalence and DALY rate of AMD in China showed an increasing and then decreasing trend,peaking at 85-89 years of age.Over time,the prevalence risk of AMD increased and then decreased,while the DALY risk continued to decline.The birth cohort analysis results showed that the overall fluctua-tion of the AMD prevalence risk cohort effect in China was small,with a decline first and then a fluctuating increase.Mean-while,the DALY risk gradually decreased as the birth cohort moved backward.It can be predicted that both the standard-ized prevalence and the standardized DALY rate of AMD may present an upward trend in China from 2022 to 2035.Conclu-sion From 1990 to 2021,the standardized prevalence of AMD in China displays an upward trend,while its standardized DALY rate exhibits a downward trend.Notably,the disease burden is more pronounced in the female population compared with the male population.With the continued aging of the population,it can be predicted that both the standardized preva-lence and DALY rate of AMD will escalate from 2022 to 2035.This finding underscores the need for targeted interventions,particularly for elderly women.Meanwhile,it is necessary to enhance health education for the whole population and formu-late effective public health policies to alleviate the disease burden associated with AMD in China.

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.

Objective To explore the role of zinc finger protein 36 (ZFP36) in regulating osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and preosteoblasts. Methods ZFP36 expression was observed in primary mouse BMSCs and mouse preosteoblasts (MC3T3-E1 cells) during induced osteogenic differentiation. Zfp36-deficient cell models were constructed in the two cells using RNA interference technique and the changes in differentiation capacities of the transfected cells into osteoblasts were observed. Transcriptome sequencing was used to investigate the potential mechanisms of ZFP36 for regulating osteoblast differentiation of the two cells. U0126, a ERK/MAPK signal suppressor, was used to verify the regulatory mechanism of Zfp36 in osteogenic differentiation of Zfp36-deficient cells. Results During the 14-day induction of osteogenic differentiation, both mouse BMSCs and MC3T3-E1 cells exhibited increased expression of ZFP36, and its mRNA expression reached the peak level on Day 7 (P<0.0001). The Zfp36-deficient cell models showed reduced intensity of alkaline phosphatase (ALP) staining and alizarin red staining with significantly lowered expressions of the osteogenic marker genes including Alpl, Sp7, Bglap and Ibsp (P<0.01). Transcriptome sequencing verified the reduction of bone mineralization-related gene expressions in Zfp36-deficient cells and indicated the involvement of ERK signaling in the potential regulatory mechanism of Zfp36. Immunoblotting showed that pERK protein expression increased significantly in Zfp36-deficient cells compared with the control cells. In Zfp36-deficient MC3T3-E1 cells, inhibition of activated ERK/MAPK signaling with U0126 resulted in obviously enhanced ALP staining and significantly increased expressions of osteoblast differentiation markers Runx2 and Bglap (P<0.05). Conclusions ZFP36 is involved in the regulation of osteoblast differentiation of mouse BMSCs and preosteoblasts, and ZFP36 deficiency causes inhibition of osteoblast differentiation of the cells by activating the ERK/MAPK signaling pathway.

Objective To explore the role of zinc finger protein 36 (ZFP36) in regulating osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and preosteoblasts. Methods ZFP36 expression was observed in primary mouse BMSCs and mouse preosteoblasts (MC3T3-E1 cells) during induced osteogenic differentiation. Zfp36-deficient cell models were constructed in the two cells using RNA interference technique and the changes in differentiation capacities of the transfected cells into osteoblasts were observed. Transcriptome sequencing was used to investigate the potential mechanisms of ZFP36 for regulating osteoblast differentiation of the two cells. U0126, a ERK/MAPK signal suppressor, was used to verify the regulatory mechanism of Zfp36 in osteogenic differentiation of Zfp36-deficient cells. Results During the 14-day induction of osteogenic differentiation, both mouse BMSCs and MC3T3-E1 cells exhibited increased expression of ZFP36, and its mRNA expression reached the peak level on Day 7 (P<0.0001). The Zfp36-deficient cell models showed reduced intensity of alkaline phosphatase (ALP) staining and alizarin red staining with significantly lowered expressions of the osteogenic marker genes including Alpl, Sp7, Bglap and Ibsp (P<0.01). Transcriptome sequencing verified the reduction of bone mineralization-related gene expressions in Zfp36-deficient cells and indicated the involvement of ERK signaling in the potential regulatory mechanism of Zfp36. Immunoblotting showed that pERK protein expression increased significantly in Zfp36-deficient cells compared with the control cells. In Zfp36-deficient MC3T3-E1 cells, inhibition of activated ERK/MAPK signaling with U0126 resulted in obviously enhanced ALP staining and significantly increased expressions of osteoblast differentiation markers Runx2 and Bglap (P<0.05). Conclusions ZFP36 is involved in the regulation of osteoblast differentiation of mouse BMSCs and preosteoblasts, and ZFP36 deficiency causes inhibition of osteoblast differentiation of the cells by activating the ERK/MAPK signaling pathway.

Objective:To investigate the application value of modified multivisceral trans-plantation (MMT) in chronic intestinal pseudo-obstruction (CIPO) secondary to autoimmune enteril leiomyositis (AEL).Methods:The retrospective and descriptive study was conducted. The clinico-pathological data of a recipient who was admitted to Beijing Tsinghua Changgung Hospital Affiliated to Tsinghua University on February 2022 and underwent MTT for CIPO secondary to AEL were collected. The recipient was a male, aged 29 years old. Results of preoperative histopathological examination showed that there were muscle plexus and ganglion cells in the rectum, sigmoid colon, ascending colon, intrinsic muscle layer of ileum, and a small amount of submucosal layer. There was also a small amount of chronic inflammatory cell infiltration in the muscle, indicating a high possi-bility of diagnosis of neurogenic CIPO.Results:(1) Surgical situations. The operation time was 14 hours and 30 minutes, and the cold ischemia time was 9 hours and 30 minutes. The intra-operative blood product dosage included 14 U of red blood cells, 1 400 mL of fresh frozen plasma, and two therapeutic doses of platelets. (2) Postoperative histopathological examination. Results of postoperative histopathological examination showed chronic inflammation and local erosion of the small intestine and duodenal mucosa, with scattered disappearance of the focal mucosal muscle layer; There is a large infiltration of CD3 + and CD8 + lymphocytes in the lamina propria, especially in the muscularis propria. In severe lesions, there is infiltration of ribbon lymphocytes in the subserosal and muscular layers; Muscle fiber degeneration, reduction, and fibrosis. Deposition of pigment granules in the cytoplasm of smooth muscle cells; No abnormalities were found in the intermuscular, submu-cosal ganglia, and Cajal cells; Fibrosis of the serosal layer with local cellulose exudation; Chronic inflammation of the colonic mucosa, scattered and focal lymphocyte infiltration in the local muscle layer, and myositis related changes. Pathological diagnosis was secondary CIPO induced by AEL. (3) Postoperative immune rejection, recurrence and treatment. Results of colonoscopy and histopatholo-gical examination at postoperative 8 days showed acute cellular rejection. The cell count of reci-pient′s B lymphocytes, CD3 + lymphocytes, CD4 + lymphocytes, and CD8 + lymphocytes were 27.00×10 3, 373.00×10 3, 179.00×10 3 and 142.00×10 3 cell/mL, respectively. Anti-immune rejection treatment was performed using tacrolimus, rabbit anti-human thymocyte immunoglobulin, methylprednisolone mycophenolate mofetil, and monoclonal antibodies against basil. The cell count of recipient′s B lymphocytes, CD3 + lymphocytes, CD4 + lymphocytes, and CD8 + lymphocytes at postoperative 57 days were 0.72×10 3, 239.59×10 3, 89.28×10 3 and 91.53×10 3 cell/mL, respectively. Results of colonoscopy and histopathological examination at postoperative 79 days showed the recurrence of AEL. The cell count of recipient′s B lymphocytes, CD3 + lymphocytes, CD4 + lymphocytes, and CD8 + lymphocytes were 0.32×10 3, 264.92×10 3, 46.95×10 3 and 169.54×10 3 cell/mL, respectively. The tacrolimus and methylprednisolone were used for treatment. Results of colonoscopy and histopathological examina-tion at postoperative 89 days showed AEL recurrence without remission. The cell count of recipient′s B lymphocytes, CD3 + lymphocytes, CD4 + lympho-cytes, and CD8 + lymphocytes were 0.28×10 3, 187.00×10 3, 55.52×10 3 and 92.45×10 3 cell/mL, respec-tively. The tacrolimus and methylprednisolone were used for treatment. Results of colonoscopy and histopathological examination at postoperative 92 days showed the intestinal mucosa had returned to a normal state. (4) Postoperative oral feeding time and time to get rid of parenteral nutrition. The recipient began oral feeding at postoperative 28 days and eliminated parenteral nutrition at postoperative 35 days. (5) Follow-up. The recipient was discharged 114 days after surgery and as of the follow-up deadline, the graft function was good. The recipient maintained a low-fat, high sugar, and high protein diet, completely consumed orally, with a body mass index of 22 kg/m 2, and has returned to normal work. Conclusion:MMT can be used for the treatment of CIPO secondary to AEL.

Objective To analyze the clinical features of children with EV71 positive hand,foot,and mouth disease(HFMD)and EV71 vaccination,and to explore the relationship between the occurrence of severe disease and the preventive effect of EV71 vaccine.Methods From January 1,2020 to December 31,2022,the clinical data of 131 children with HFMD diagnosed with EV71 infection in Kunming Children's Hospital were retrospectively analyzed.The stool samples of patients with clinically confirmed HFMD were selected for enterovirus nucleic acid detection.The clinical data and EV71 vaccination status of children with universal enterovirus positive and EV71 positive HFMD were analyzed.Results Among the 131 positive cases detected,there were 116 mild cases and 15 severe cases.Among the 80 children who received phone consultations about their EV71 vaccine status,17 were vaccinated,and 63 were not vaccinated.The vaccinated children were all mild cases,while among the unvaccinated children,6 were severe cases.From 2020 to 2022,the period from April to September each year is the peak period for detecting EV71-positive hand,foot,and mouth disease(χ2 = 125.705,P = 0.000).The positive detection rate for children under 1 year old and over 5 years old was higher than that for children aged 1 to 5 years(χ2 = 8.765,P = 0.033),and there was no significant difference in the positive detection rate between boys and girls(χ2 = 1.221,P = 0.269).Conclusion EV71 vaccine is of great significance in reducing the occurrence of severe cases.Combined with the current low vaccination rate in Kunming,Yunnan Province,it is suggested that relevant institutions should continue to increase the publicity of EV71 vaccination.