Objective To establish testing and evaluation methods for radiation shielding performance of a self-shielded radiotherapy system by measuring the radiation levels around the self-shielded head and neck radiotherapy system. Methods A total of 14 monitoring points were selected outside the restricted zone of the system. Under radiation conditions from five different fixed directions, an ion chamber survey meter was used to measure and identify the maximum ambient dose equivalent rate at the 14 points. The time-averaged dose rate was then calculated based on the workload. In accordance with relevant radiation protection standards, an instantaneous dose rate of 10 μSv/h and a time-averaged dose rate of 2.0 μSv/h were proposed as the criteria for shielding protection evaluation. Results Based on the ambient dose equivalent rates at the 14 monitoring points outside the restricted zone, the maximum instantaneous dose rate outside the restricted zone was 7.4 μSv/h. With a workload of 15 patients per day, the maximum time-averaged dose rate was 1.0 μSv/h, which can be used as the criteria for shielding protection evaluation. Conclusion By considering both instantaneous dose rate and time-averaged dose rate, a comprehensive safety assessment of the radiation shielding performance of a self-shielded radiotherapy system can be conducted.

Objective:To investigate the safety, efficacy and effective dose of empagliflozin in the treatment of glycogen storage disease type Ⅰb (GSD Ⅰb).Method:This was a cross sectional study. A total of 28 children with GSDⅠb who started oral empagliflozin treatment from January 2021 to June 2023 in the WeChat group of patients with glycogen storage disease were selected as the study objects. Clinical data such as general situation, current situation of medication and adverse reactions of the children were collected through questionnaires from June 18 to 30, 2023. The differences of symptoms and laboratory tests before and after empagliflozin treatment were compared by using paired chi-square test and Wilcoxon signed rank sum test.Results:Totally 28 children with GSD Ⅰb were from 12 different provinces, autonomous regions and municipalities in China. There were 14 males and 14 females. Empagliflozin treatment was started at the age of 4.8 (2.4, 10.8) years, the time of treatment was 14.5 (11.3, 21.5) months, the initial dosage was (0.23±0.11) mg/(kg·d), and the maintenance dosage was (0.28±0.12) mg/(kg·d). Empagliflozin showed positive effects on neutropenia, severity of inflammatory bowel disease like symptoms( Z=-3.70 , -2.65, both P<0.05), The proportion of recurrent oral ulcers, recurrent bacterial infections and anemia was significantly lower than that before medication (18% (5/28) vs. 46% (13/28), 14% (4/28) vs. 46% (13/28), 21% (6/28) vs. 46% (13/28), χ2=4.05, 5.26, 3.05 , all P<0.05). Granulocyte colony-stimulating factor (GCSF) was once used in 5 children with GSD Ⅰb, all of them had completely stopped GCSF after empagliflozin treatment. The most common adverse events during empagliflozin treatment were hypoglycemia (5 children) and urinary infection (3 children). All 28 patients had no serious adverse reactions. Conclusions:Empagliflozin can increase the neutrophil count of children with GSD Ⅰb, and had a favorable effect on symptoms such as recurrent oral ulcers, and recurrent infection. The common adverse events during empagliflozin treatment were hypoglycemia and urinary infection.

Glycogen storage disease type Ⅰb（GSD Ⅰb）is an autosomal recessive genetic disease characterized by abnormal glycogen metabolism.The clinical manifestations include signs of metabolic abnormality of the typical GSD I，and the patients with GSD Ⅰb also have neutropenia and symptoms including recurrent infection，oral and intestinal mucosal ulcers，inflammatory bowel diseases and autoimmune thyroiditis.However，the detailed mechanism of GSD Ⅰb has not been clarified.Treatment with sodium-dependent glucose transporters 2（SGLT2）inhibitors improves both neutropenia and neutrophil function through reducing 1，5-anhydroglucitol（1，5-AG）in plasma，as well as alleviates the related clinical symptoms，so SGLT2 inhibitors are increasingly used in the treatment of GSD Ⅰb.Here it reviews the neutropenia mechanism and recent advances in animal-based research and clinical application of SGLT2 inhibitor therapy for GSD Ⅰb.

Glycogen storage diseases (GSDs)refer to a group of metabolic disorders caused by congenital enzyme deficiencies. This group of diseases are characterized by abnormal glycogen metabolism. Most subtypes can lead to increased glycogen accumulation in tissues of the liver, muscles, kidneys etc. GSD type Ⅰ (GSDⅠ) is the most common type of the liver glycogen storage diseases that are caused by a deficiency in glucose-6-phosphatase in the liver, kidneys, and intestines. This typle has two subtypes: type Ⅰa and type Ⅰb(GSDⅠb). Recently, research into the molecular mechanisms of GSD Ⅰb made further progress, leading to significant improvements in clinical diagnosis and the new treatment methods based on the pathogenesis. This article summarizes the current research status of diagnosis and screening, molecular genetic mechanisms, and treatment of GSD Ⅰb. The article also points out the opportunities, the challenges and future possibilities.

Objective:To investigate the association between ureaplasma urealyticum (UU) colonization in the respiratory tract and bronchopulmonary dysplasia (BPD) in extremely preterm or extremely low birth weight infants.Methods:This was a retrospective study involving preterm infants with gestational age <28 weeks or birth weight <1 000 g who was hospitalized in the Neonatal Intensive Care Unit (NICU) of Chengdu Women's and Children's Central Hospital from June 2019 to March 2022. Respiratory tract secretion was collected for UU DNA detection within 24 h after admission. All the participants were divided into the UU-positive or negative groups based on the detection results. Clinical characteristics of the two groups were analyzed using Mann-Whitney U, t-, or Chi-square tests (Fisher exact test). Results:A total of 82 infants were enrolled, including 31 cases (37.8%) in the UU-positive group and 51 patients (62.2%) in the negative group. Among the 30 cases treated with azithromycin in the positive group, 27 (90.0%, 27/30) turned negative after two courses of treatment. The rates of premature rupture of membranes [51.6% (16/31) vs 17.6% (9/51), χ2=10.50] and prenatal antibiotic exposure [71.0% (22/31) vs 47.1% (24/51), χ2=4.47] in the UU-positive group were both higher than those in the UU-negative group (both P<0.05). Multivariate logistic regression analysis showed that premature rupture of membranes ( OR=5.893, 95% CI: 2.016-17.228) and gestational age ( OR=0.663, 95% CI: 0.441-0.999) were independent risk factors for UU colonization (both P<0.05). UU-positive group had a longer duration of oxygen use [ M ( P25- P75), 1 756 h (1 385-2 088 h) vs 1 357 h (1 128-1 656 h), Z=2.98], a longer length of hospital stay [81 d (70-105 d) vs 68 d (59-84 d), Z=3.05], and higher hospitalization costs [(201 574±70 326) yuan vs (161 288±53 412) yuan, t=－2.74] compared to the UU negative group (all P<0.05). The incidence of BPD [74.2% (23/31) vs 47.1% (24/51), χ2=5.80] and retinopathy of prematurity [93.4% (29/31) vs 74.5% (38/51), χ2=4.68] in the UU positive group was higher than those in the UU-negative group (both P<0.05). No significant correlation was found between UU colonization and the severity of BPD ( P>0.05). Conclusion:UU colonization may increase the incidence of BPD, but there was no clear correlation with the severity of BPD.

Objective To explore the feasibility of quartz glass for radiotherapy dosimetry through the experimental study of the thermoluminescence characteristics of synthetic quartz glass. Methods The thermoluminescence glow curves of quartz glass under different annealing conditions were analyzed, the thermoluminescence characteristics of quartz glass were studied, and the measurement parameters were optimized. Using the Co-60 reference radiation field in the National Secondary Standard Dosimetry Laboratory, the quartz glass samples under different annealing conditions were irradiated following the dose levels of radiotherapy, i.e., 0.5, 1.0, 2.0, 4.0, 6.0, 8.0, and 10.0 Gy, respectively. According to the relationship between the absorbed dose of quartz glass and the relative thermoluminescence signal intensity, the linearity and dispersion of the dose response of quartz glass were obtained, and the feasibility of quartz glass for radiotherapy dosimetry was analyzed. Results The linear correlation coefficient of dose response of quartz glass under annealing condition of 430℃ for 10 min was 0.9984, and the dose response dispersion was 0.97% at the absorbed dose of 2 Gy. The linear correlation coefficient of dose response of quartz glass under annealing condition of 600℃ for 1 h was 0.9911, and the dose response dispersion was 1.4% at the absorbed dose of 2 Gy. Conclusion Preliminary results suggest that quartz glass with annealing condition of 430℃ for 10 min has the potential to be used for radiotherapy dosimetry.

Objective To investigate the effects of CeO2 NP subacute exposure on body weight,organ structures,and redox indicators in male mice.Methods Thirty-five male ICR mice were randomly divided into five groups with seven mice in each group.Normal control and CeO2 NP(100,500,1000 and 5000 μg/kg)groups were included.Mice were injected with CeO2 NPs intraperitoneally every other day for 28 days.Results Compared with the control group,no significant difference was found in weight gain(P>0.05),but significant differences were observed in the liver coefficient,epididymal coefficient,and sperm survival rate(P<0.01).In the 5000 μg/kg group,CeO2 NPs were deposited in the liver and spleen,and granuloma was found SOD and GSH-Px activities in serum of the 100 μg/kg group were increased,while MDA content was decreased,which indicated the antioxidant effect of CeO2 NPs.With the increase in dose,oxidative stress induced by CeO2 NPs was enhanced.Conclusions Low-dose-CeO2 NPs are safe and exert an antioxidant effect.With the increase in dose,the toxicity of CeO2 NPs also increases gradually.

Objective To calculate the energy dependence of absorbed dose in EBT3 film, and to reveal the error in the measurement of proton absorbed dose by EBT3 film. Methods Beam energy was gradually increased in the clinical photon and proton energy ranges. Geant4 was used to calculate the difference in absorbed dose between EBT3 film and the same volume of water. The results were compared with the theoretical values. Results For photons and protons, the thresholds for absorbed dose with energy dependence were 100 keV and 11 MeV, respectively. The energy dependence was consistent with the theoretical values when the photon and proton energies were higher than the corresponding thresholds, and irrelevant to the theoretical values when energies were lower than the thresholds. The differences between the proton Bragg peak and 50% dose point and the actual positions were less than 1%. Conclusions For protons and photons with high energy, the energy dependence of absorbed dose in EBT3 film is negligible. For protons and photons with low energy, EBT3 film shows very different energy dependence of absorbed dose, which should be taken into consideration. The proton Bragg peak and 50% dose point measured by EBT3 film are basically the same as the actual positions.

Objective:The investigation and research on the application status of Hepatic Venous Pressure Gradient (HVPG) is very important to understand the real situation and future development of this technology in China.Methods:This study comprehensively investigated the basic situation of HVPG technology in China, including hospital distribution, hospital level, annual number of cases, catheters used, average cost, indications and existing problems.Results:According to the survey, there were 70 hospitals in China carrying out HVPG technology in 2021, distributed in 28 provinces (autonomous regions and municipalities directly under the central Government). A total of 4 398 cases of HVPG were performed in all the surveyed hospitals in 2021, of which 2 291 cases (52.1%) were tested by HVPG alone. The average cost of HVPG detection was (5 617.2±2 079.4) yuan. 96.3% of the teams completed HVPG detection with balloon method, and most of the teams used thrombectomy balloon catheter (80.3%).Conclusion:Through this investigation, the status of domestic clinical application of HVPG has been clarified, and it has been confirmed that many domestic medical institutions have mastered this technology, but it still needs to continue to promote and popularize HVPG technology in the future.

Objectives:To observe the anatomical location and mechanism of axis ring fractures (ARF) using 3-D CT scans, and propose a new classification for such fractures.Methods:By reviewing prospectively maintained database collecting ARF from 7 medical centers in China, 202 patients were included in this study. According to anatomical location, ARFs were classified into axis arthrosis fracture (AAF) and axis bony damage (ABD). The axis ring was divided into anterior, middle, and posterior rings, based on the border of the pars interarticularis (or pedicle) of axis. According to the features of ARF and previous study, a new classification was proposed based on the anatomical features of different fracture patterns, which was divided into three types and six subtypes (A1, A2, B1, B2, C1 and C2). The incidence of AAF and ABD and their distribution in different location of axis ring and the new classification, were observed.Results:In 202 patients with ARF, 501 anatomical structures were involved. 288 AAFs were found in 178 patients (288/501, 57%), while 213 ABDs were found in 149 patients (213/501, 43%). In anterior ring, 304 structures (304/501, 61%) were involved in injury, with 225 AAF and 79 ABD. In middle ring, 99 structures (99/501, 20%) were involved in injury, and all of them were ABD. In posterior ring, 98 structures (98/501, 19%) were involved in injury, with 63 AAF and 35 ABD. The anterior ring injuries (61%) were more common than middle (20%) or posterior ring (19%). In anterior ring, AAF (84%) were morecommon than ABD (16%); In middle ring, all the injuries were ABD; In posterior ring, AAFs (64%) were more common than ABD (36%). Type A fractures were featured with pedicle fractures and were identified in 30 patients (30/202, 15%). Type A1 fractures were bilateral pedicle fracture lines symmetrically or asymmetrically and identified in 12 (6%) patients; Type A2 fractures were pedicle fracture lineson one side and inferior articular facet injuries or lamina fractures on the otherside and identified in 18 (9%) patients. Type B fractures were featured with superior articular facet injuries or posterior wall of C2 body fractures on one side and identified in 136 patients (67%). Type B1 fractures were superior articular facet injuries or posterior wall of C2 body fractures on one side and pedicle fracture on the other side and identified in 57 (28%) patients; Type B2 fractures were superior articular facet injuries or posterior wall of C2 body fractures on one side and inferior articular facet injuries or lamina fractures on the otherside and identified in 79 (39%) patients. Type C fractures were featured with bilateral superior articular facet injuries or posterior wall of C2 body fractures and identified in 36 patients (18%). Type C1 fractures were bilateral superior articular facet injuries or posterior wall of C2 body fractures symmetrically and identified in 22 (11%) patients; Type C2 fractures were bilateral superior articular facet injuries or posterior wall of C2 body fractures asymmetrically and identified in 14 (7%) patients.Conclusion:ARF could occur in different anatomical locations, and most of these fractures were caused by hyperextension and axial load on superior articular facet on one or two sides. The new CT classification of ARF with three types and six subtypes might provide all fracture patterns, which could be useful for the choice of proper diagnosis and treatment for such fractures.