Background Air pollution exposure has a significant impact on maternal and child health. However, the research on the association between ambient ozone (O₃) exposure during pregnancy and the risk of premature birth in newborns is limited, and the conclusions are inconsistent. Objective To investigate the association of ambient O₃ exposure during pregnancy with the risk of preterm birth in Guangdong Province. Methods Data of pregnant women in Guangzhou from 2013 to 2019 and Foshan from 2018 to 2023 were collected, and O₃ concentrations during different trimesters were assessed according to maternal residential addresses. Bilinear interpolation was used to evaluate the concentrations of air pollution. A cohort study design was adopted in our study. Restricted cubic spline curves were used to evaluate the exposure-response relationship between O₃ exposure and preterm birth risk and explore potential exposure threshold of O₃. Logistic regression models were used to evaluate the association of O₃ exposure with preterm birth. Results A total of 702 924 pregnant women were included in this study, of whom 43 051 (6.12%) were preterm. The average O₃ exposure concentrations of pregnant women during the first, second, third, and whole trimesters were 95.51, 97.51, 100.60, and 97.87 μg·m⁻³, respectively. We observed J-shaped associations between O₃ exposure and preterm birth risk during the second, third, and whole trimesters of pregnancy using restricted cubic spline curves. This study found that there were threshold concentrations between O₃ exposure and preterm birth risk during different gestational periods, and the threshold concentrations in the first, second, third, and whole trimesters were 112.32, 99.83, 111.74, and 112.46 μg·m⁻³, respectively. During the second, third, and whole trimesters of pregnancy, after adjusting for maternal age, baby sex, pre-pregnancy body mass index, mode of delivery, baby birth weight, gestational diabetes, and gestational hypertension, the odds ratios (OR) of preterm birth were 1.02 (95%CI: 1.01, 1.04), 1.02 (95%CI: 1.00, 1.03), and 1.17 (95%CI: 1.13, 1.21) for each 10 μg·m⁻³ increase in O₃ concentration above the O₃ threshold. No significant association was found between O₃ exposure and the risk of preterm birth during the first trimester. Conclusion There is a nonlinear association between the risk of preterm birth and O₃ exposure during pregnancy, and higher concentrations of O₃ exposure during pregnancy are associated with the risk of preterm birth. Above the O₃ threshold concentration during pregnancy, especially during the second, third, and whole trimesters, the risk of preterm birth elevates with the increase of O₃ exposure concentrations.

To guide transfusion practice in critically ill children who often need plasma and platelet transfusions, the Transfusion and Anemia Expertise Initiative-Control/Avoidance of Bleeding (TAXI-CAB) developed Recommendations and Expert Consensus for Plasma and Platelet Transfusion Practice in Critically Ill Children. This guideline addresses 53 recommendations related to plasma and platelet transfusion in critically ill children with 8 kinds of diseases, laboratory testing, selection/treatment of plasma and platelet components, and research priorities. This paper introduces the specific methods and results of the recommendation formation of the guideline.

Objective To investigate the neural basis of glucagon-like peptide-1(GLP-1)in regulating glucose homeostasis and elucidate the molecular mechanisms.Methods Male Glp1r-IRES-Cre,Glp1r-KO,and wild-type mice were used in this study.Fiber photometry was employed to record Ca2+signals of neurons in ventromedial hypothalamus(VMH)and patch-clamp was used to analyze electrophysiological properties of GLP-1 receptor-positive(GLP-1RVMH)neurons.Viral stereotaxic injections,chemogenetics,plasma hormone assays,and routine glucose metabolism assessments were combined to determine the regulatory role of GLP-1RVMH neurons in glucose homeostasis.Tissue and cell mitochondrial respiratory function assays,transmission electron microscopy,and conventional molecular biology methods were used to explore the mechanism by which GLP-1R agonists regulate glucose homeostasis.Results When the glucose concentration decreased from 5.0 mmol/L to 0.5 mmol/L,the action potential frequency of GLP-1RVMH neuron decreased significantly[(4.51±0.80)Hz vs.(1.43±0.51)Hz,P<0.01].Activation of GLP-1RVMH neuron significantly enhanced insulin secretion[(7.60±0.56)μU/mL vs.(11.34±0.93)μU/mL,P<0.01],while inhibition of these neuronal activities impaired the hypoglycemic efficiency of GLP-1 agonists[(32.03%±0.91%)vs.(25.77%±1.09%),P<0.001)].Mechanistically,GLP-1 regulated glucose homeostasis through Drp1 phosphorylation-mediated mitochondrial fission and improved mitochondrial energy metabolism.Conclusion GLP-1RVMH neurons are a class of glucose-excited neurons,and which activated directly promotes secretion of insulin.The hypoglycemic effect of GLP-1R agonists depend on the neuronal activity of GLP-1RVMH.

Objective To explore the predictive value of dose surface histogram(DSH)in image guided radiotherapy(IGRT)for radiotherapy-induced acute radiation proctitis(ARP)in cervical cancer(CCA).Methods Totally 380 patients with CCA IGRT admitted to some hospital from May 2019 to May 2023 were selected prospectively and randomly divided into a control group(n=1 80)and an experimental group(n=200).The patients in the 2 groups were followed up and the incidence rates of ARP were counted,and rectal dose distribution was evaluated using dose volume histogram(DVH)in the control group and DSH in the experimental group.The predictive values of DVH and DSH for ARP were evaluated and compared using ROC curves.Statistical analysis was performed using SPSS 21.0 software.Results The two groups did not have statistically significant difference in the incidence rate of ARP(P＞0.05),while there were significant differences in the evaluation indicators of the rectal dose distribution(P＜0.05).V40,V50,S40 and S50 proved to have low predictive values for grade Ⅰ-Ⅳ ARP with AUC 0.700(P＜0.05);V60 and S60 had moderate predictive values for grade Ⅰ-Ⅳ ARP with AUC greater than 0.700 and less than or equal to 0.900(P＜0.05);V70,V78,S70 and S7s showed high predictive values for grade Ⅰ-Ⅳ ARP with AUC higher than 0.900(P＜0.05).Delong's test results indicated that DVH and DSH had no significant differences in AUC when used to predict gradeⅠ-Ⅳ ARP(allP＞0.05).Conclusion DSH is essentially the same as DVH when used for the prediction of grade Ⅰ-Ⅳ ARP due to CCA IGRT,and thus can be used for the supplementation and optimization of radiotherapy planning systems.[Chinese Medical Equipment Journal,2025,46(3):48-53]

Objective: To explore the association between negative life events and smartphone addiction among middle school students, so as to provide theoretical support and practical guidance for prevention and intervention of smartphone addiction among middle school students. Methods: Using cluster sampling, 8 890 students were selected to survey from 27 junior high schools and 3 senior high schools in a district of Shenzhen in 2022 (baseline) and 2023 (followup). Data were collected through selfresigned questionnaires on basic information, the Smartphone Addiction Scale-Short Version, and the Adolescent Selfrating Life Events Checklist. Mixedeffects models were employed to analyze the association. Results: Compared to 2022, the punishment scores of middle school students in 2023 [1.00 (0.00, 6.00) and 1.00 (0.00, 6.00)] decreased (Z=4.27), while the scores of interpersonal stress, learning stress and adaptation [4.00(0.00, 8.00), 4.00(0.00, 8.00); 4.00(1.00, 8.00), 5.00(2.00, 9.00); 2.00 (0.00, 6.00), 3.00 (0.00, 7.00)] increased (Z=-3.04, -8.36, -6.80) (P<0.01). Mixedeffects models revealed a positive doseresponse relationship between negative life events and smartphone addiction (OR=1.08-1.17, P<0.01). Stepwise regression showed independent positive effects of interpersonal stress (OR=1.05), academic stress (OR=1.03), and adaptation stress (OR=1.11) on smartphone addiction (P<0.01). Subgroup analysis of nonaddicted students in 2022 confirmed persistent associations for academic stress (OR=1.03) and adaptation (OR=1.07) (P<0.01). Conclusion Negative life events exhibit a positive doseresponse relationship with smartphone addiction, particularly interpersonal stress, academic stress, and adaptationrelated events.

Objective: To explore the longitudinal association between only-child status and smartphone addiction among middle school students, so as to provide a basis for establishing family intervention measures for smartphone addiction in middle school students. Methods: In October 2022 and October 2023, a preliminary survey and follow-up were conducted among 8 759 middle and high school students from 30 schools in a district of Shenzhen. A self-designed questionnaire was used to determine whether the students were the only-child, and the Chinese Version of the Smartphone Addiction Scale-Short Version (C-SAS-SV) was utilized to assess the students smartphone addiction status. A multilevel mixed-effects model and subgroup analysis were applied to examine the association between only-child status and smartphone addiction among middle school students. Results: During 2022 to 2023, the prevalence of smartphone addiction in the cohort of middle school students increased from 24.1% to 25.2%. Compared with only-child, non-only child were more likely to be addicted to smartphones (adjusted model: OR =1.2, 95% CI =1.1-1.4) and also scored higher on smartphone addiction (adjusted model: β =0.9, 95% CI =0.2-1.5)( P <0.05). Subgroup analysis further revealed that compared to baseline, non-only child demonstrated an increased prevalence of smartphone addiction (adjusted model: OR = 1.2 , 95% CI =1.0-1.5) and higher addiction scores (adjusted model: β =0.8, 95% CI =0.2-1.5) after one year( P <0.05). Conclusions Non-only child face higher risk of smartphone addiction. Under the current population policy, it is crucial to address smartphone addiction among middle school students who is not only child.

Objective: To explore the potential causal association between adolescent compulsive behaviour and smartphone addiction based on longitudinal data, so as to provide reference for the establishment of adolescent smartphone addiction interventions. Methods: A preliminary survey and follow-up were conducted on 8 907 middle and high school students in a district of Shenzhen in 2022 and 2023, respectively. Compulsive behaviours were measured by using the Mental Health Inventory for Middle School Students-60 Items (MMHI-60), smartphone addiction was assessed by using the Smartphone Addiction Scale-Short Version ( SAS- SV), and the associations between compulsive behaviours and smartphone addiction were analysed by using multilevel mixed-effects models and subgroup analyses. Results: Smartphone addiction detection rates among middle school students were significantly associated with genders, father s education level, mother s education level, study load subgroups, and whether or not they were single-parent families, and there were statistical differences ( χ 2=17.21-175.34, P <0.05). Students with compulsive behaviours were 2.98 times more likely to develop smartphone addiction than those without compulsive behaviours ( OR=2.98, 95%CI=2.77-3.22, P <0.05). Subgroup analysis of middle school students without smartphone addiction in the first year found that compulsive behaviours significantly predicted smartphone addiction ( OR= 1.76 , 95%CI=1.54-2.01, P <0.05). Conclusion There is a potential causal association between obsessive-compulsive behaviours and smartphone addiction in middle school students, and obsessive-compulsive behaviours in middle school students could significantly predicted the occurrence of smartphone addiction.

Objective The aim of the study is to reveal the polymorphisms of Eustrongylides spp.in Monopterus albus.Methods A total of five Eustrongylides spp.collected from five M.albus in the Yongzhou area were sampled to amplify ribosomal ITS sequence by PCR in vitro,then sequenced after extracting the DNA templates of Eustrongylides.The phylogenetic tree based on the ITS sequence was also constructed to explore the evolutionary history of Eustrongylides.Results The length of the ITS sequence of the five Eustrongylides spp.is approximately 933 bp,and the genetic differences between the isolates are 0.00％-0.90％and the genetic inheritance differences with other nematodes are 15.5％-18.20％,maintaining a certain genetic distance from other families.Conclusions The ITS sequence of Eustrongylides spp.in M.albus will be used as a genetic marker for the molecular identification of Eustrongylides spp.and will provide a basis for the prevention and control of Eustrongylides spp.in the future.

Apical microsurgery is accurate and minimally invasive, produces few complications, and has a success rate of more than 90%. However, due to the lack of awareness and understanding of apical microsurgery by dental general practitioners and even endodontists, many clinical problems remain to be overcome. The consensus has gathered well-known domestic experts to hold a series of special discussions and reached the consensus. This document specifies the indications, contraindications, preoperative preparations, operational procedures, complication prevention measures, and efficacy evaluation of apical microsurgery and is applicable to dentists who perform apical microsurgery after systematic training.
Microsurgery/standards* ; Humans ; Apicoectomy ; Contraindications, Procedure ; Tooth Apex/diagnostic imaging* ; Postoperative Complications/prevention & control* ; Consensus ; Treatment Outcome