Objective To observe the influence of different energy windows of the medium-energy general-purpose(MEGP)collimator on image quality,so as to optimize the energy window of yttrium-90(90Y)bremsstrahlung SPECT imaging.Methods 90Y bremsstrahlung spectrum was acquired,and the sensitivity,percentage of the source counts in useful field of view(S/FOV%)and signal-to-background ratio(S/B)of 90Y bremsstrahlung SPECT imaging at MEGP under different energy windows were compared.Results The energy spectrum of 90Y bremsstrahlung was a continuous curve,with the peak of 76.2 keV with MEGP collimator.The images obtained with MEGP collimator were clear,and no significant differences of S/FOV%nor S/B was found between 10%and 20%window width groups(both P＞0.05),but the sensitivities of the latter was higher than the former(P＜0.05).The sensitivity of 70-90 keV images was relatively high,while the S/FOV%and S/B had decreased.The S/FOV%and S/B of images ranging from 40-60 keV were high,but the sensitivity was low.Images acquired with 100 keV±20%showed fairly high sensitivity,S/FOV%and S/B,which was 69.73%,0.62 and 1.64,respectively.Conclusion When performing 90Y bremsstrahlung SPECT with MEGP collimator,the image quality at 20%window width was better than at 10%window width,and 100 keV±20%showed fairly high sensitivity and not significantly decreased S/FOV%and S/B.

Objective:To study the clinical characteristics，diagnosis，treatment and prognosis of neonatal appendicitis.Methods:From January 2019 to December 2022，19 neonates with appendicitis（appendicitis group）and 38 neonates with sepsis（sepsis group）admitted to the Neonatal Department of Xi'an Children's Hospital Affiliated to Xi'an Jiaotong University were studied.The characteristics of clinical manifestation，imaging，treatment and prognosis of neonates in two groups were analyzed,retrospectively.Results:Among 19 neonates with appendicitis，31.6% were premature，the mean birth weight was（2 927.9±796.2）g，male∶female=2.17∶1.Abdominal distention（8/19，42.1%）and fever（8/19，42.1%）were the first symptoms of appendicitis，and the first symptoms of sepsis were mainly fever（20/38，52.6%）and poor reaction（7/38，18.4%）.In the appendicitis group，the proportions of abdominal distension（89.5% vs. 5.3%），vomiting（36.8% vs. 2.6%），breast resistance（84.2% vs. 39.5%），mental reaction changing（94.7% vs. 71.1%）and abdominal positive signs（84.2% vs. 5.3%）were significantly higher than those in sepsis group（ P<0.05）.C-reactive protein（CRP）was elevated in 16 neonates with appendicitis and 13 neonates with sepsis，and elevated gradually in 14 neonates with appendicitis. Compared with sepsis group，CRP was higher in appendicitis group（ P<0.05）.Fifteen（78.9%）neonates with appendicitis were diagnosed only by ultrasound，mainly manifested as low echo area or liquid dark area in the right abdomen，thickening of the appendix wall or effusion in the cavity，and liquid exudation.Three（15.8%）neonates with appendicitis were diagnosed by ultrasound and CT.Eight（42.1%）neonates with appendicitis were complicated appendiceal perforation.Fifteen neonates with appendicitis were treated by conservative treatment，four cases were treated by operation，and all of them were cured and discharged. Conclusion:Abdominal ultrasonography should be improved as soon as possible in neonates with fever and septicemia，especially those with abdominal symptoms or signs，or CRP increased during treatment，and CT or surgical exploration if necessary,to confirm the diagnosis of neonatal appenditis and early treatment.

OBJECTIVE To study the relationship between frequency specific free-field tone burst cortical auditory evoked potentials(CAEP)and aided behavioral audiometry to provide rapid,reliable insights for predicting hearing intervention efficiency in hard to cooperate cochlear implant patients.METHODS The study comprised of 22 cochlear implant pediatric patients(22 ears)free-field tone burst CAEP P1 response thresholds,free-field behavioral thresholds determined within the group across frequencies 0.5,1,2 and 4 kHz were collected for correlation analysis.RESULTS The free-field tone burst CAEP P1 response thresholds and free-field behavioral audiometric thresholds in cochlear implant pediatric patients for testing frequencies 0.5,1,2,4 kHz were compared and r correlation coefficients found were 0.567,0.670,0.637 and 0.762 across the frequencies respectively(P<0.01).The mean difference between free-field CAEP P1 response threshold and free-field behavioral thresholds for cochlear implant patients differ by 5-8 dB with statistical significance.CONCLUSION Free-field tone burst CAEP can be used for cochlear implant programming validation in patients that fail to cooperate in behavioral testing,thus is applicable in cochlear implant programming clinical practice.

China prospective multicenter birth cohort (Prospective Omics Health Atlas birth cohort, POHA birth cohort) study was officially launched in 2022. This study, in collaboration with 12 participating units, aims to establish a high-quality, multidimensional cohort comprising 20 000 naturally conceived families and assisted reproductive families. The study involves long-term follow-up of parents and offspring, with corresponding biological samples collected at key time points. Through multi-omics testing and analysis, the study aims to conduct multi-omics big data research across the entire maternal and infant life cycle. The goal is to identify new biomarkers for maternal and infant diseases and provide scientific evidence for risk prediction related to maternal diseases and neonatal health.

Objective:To study the clinical and genetic characteristics of Wiskott-Aldrich syndrome (WAS) in neonates.Methods:From January 2016 to August 2022, neonates with WAS admitted to the neonatal department of our hospital were studied.Their clinical features, laboratory findings, genetic characteristics and clinical outcomes were retrospectively analyzed.Results:A total of 11 neonates(all male) were included. The mothers of 3 neonates had thrombocytopenia during pregnancy. The presenting symptoms included isolated bloody stool (4 cases), jaundice (3 cases), bloody stool with petechiae, bloody stool with hematemesis, cough and fever(1 case each). Eczema appeared from 6 d to 3 months after birth and in 6 cases during the neonatal period. None of the 11 cases had serious infection during the neonatal period. 9 cases had infection from 8 d to 5 months and 2 cases had not been infected until the last follow-up. Genetic sequencing showed four frameshift variants(c.30dupC, c.205dupT, c.1340_1343dupC and c.673_674delA), four nonsense variants(c.37C>T, c.295C>T, c.889C>T and c.823G>T) and three missense variants(c.134C>T, c.397G>A and c.341T>C). Pedigree verification of variants found 10 cases were inherited from their mothers and 1 case was de novo variant.Conclusions:WAS is characterized by bloody stool and eczema in the neonatal period, mostly without serious infections and lacking specific manifestations. Genetic screening for early identification of unexplained thrombocytopenia in male newborns should be performed as early as possible.

Objective: Based on physical activity (PA) and sedentary behavior (SB) variables on weekdays and weekends, the study aims to cluster the physical activities inside and outside kindergartens and to explore the cluster characteristics of different children using physical fitness indicators, so as to provide new strategies and methods for early childhood education and health. Methods: From March to June 2019, 291 children aged 3-6 years from 6 kindergartens in Nanchang were recruited by a stratified cluster random sampling method. The ActiGraph GT3X-BT triaxial accelerometer was used to measure and analyze the PA and SB levels inside and outside the kindergarten. A twostep clustering algorithm model was employed for cluster analysis. Physical fitness were measured and evaluated according to the "National Physical Fitness Measurement Standard Manual (Preschool Section)". Differences in physical fitness among different clusters of children were compared, and the cluster characteristics of different children were analyzed. Results: The clustering algorithm model indicated that based on six indicators, including PA and SB inside the kindergarten on weekdays, and PA and SB outside the kindergarten on both weekdays and weekends, children could be divided into three categories:active inside (high PA, low SB inside), active outside (high PA outside), and inactive (low PA, high SB both inside and outside). The average silhouette coefficient of the model was 0.3, indicating good clustering results. Both the active inside and active outside children showed significantly higher PA inside on weekdays, PA outside on weekdays and weekends, daily low intensity physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) than the inactive children ( F=157.91, 80.79 , 95.86, 95.52, 124.74, P <0.05). After adjusting for gender and age, the physical fitness scores of both active outside ( 19.03 ±0.47) and active inside (19.11±0.40) were significantly higher than those of the inactive children (17.94±0.31). Additionally, active inside children (3.91±0.14) also showed significantly better performance in continuous double-leg jumps, compared to inactive children (3.45±0.11) ( P <0.05). Conclusion Children active inside and those active outside perform well in PA. Future research should focus on the proportion of structured and unstructured PA time to enhance the overall physical fitness of children.

To analyze the methodological and reporting quality of systematic reviews of prediction models published in Chinese journals, with the aim of providing reference for enhancing the overall quality of Chinese systematic reviews of prediction models.

Objective:To evaluate the prevention effect of low dose pre-irradiation on irradiation-induced lung injury and its possible mechanism.Methods:Totally 320 6-week-old female C57BL/6j mice were divided into control (0 Gy), low-dose (0.5 Gy), high-dose (20 Gy) and low-dose pre-radiation(0.5 Gy+ 20 Gy)groups by the random number method, with 80 mice in each group. The mice in the low-dose and low-dose pre-irradiation groups were placed in the immobilization device under full consciousness and subjected to 0.5 Gy X-ray whole-body irradiation. 2 weeks later, the 0.5 Gy pre-irradiated mice were anesthetized and subjected to 20 Gy X-rays on chest, as the pre-radiation plus high dose radiation group. The mice in the control group were irradiated with mock irradiation (0 Gy). All mice were terminated at designed time points (24 h, 1 month, 3 months and 5 months) after completion of the irradiation schedule, with 20 mice/group at each time point. Then, lung tissues were taken from mice, and pathological changes were observed by hematoxylin-eosin (HE) staining and Masson′s trichrome staining. RT-qPCR and Western blot were used to detect the expressions of mRNAs and proteins of pulmonary fibrosis-related factors.Results:Pathological changes were observed in the lung tissues 1 month after a single high-dose 20 Gy irradiation, mainly including radiation pneumonitis and a small amount of collagen accumulation, which was more serious than low-dose pre-irradiation group, and these pathological changes became more severe when the time after irradiation increased. Meanwhile, the mRNA and protein levels of proSP-C and HOPX in the low-dose pre-irradiation group were higher than those in the high-dose group, except for proSP-C protein expression at 3 and 5 months post-irradiation. A more significant change was that the mRNA level of TGF-β1 in the high-dose group was 5.8-13.6 times higher than that in the other groups at 5 months after irradiation, as well as β-catenin mRNA ( t=4.22, 5.11, P<0.05). At the same time, in the early period (24 h and 1 month) post-irradiation, the level of vimentin protein in the low-dose pre-irradiation group was significantly higher than that in the high-dose group ( t=6.54, 4.28, P<0.05). Conclusions:When the mice were pre-irradiated with 0.5 Gy X-rays, an adaptive protective response was induced in lung tissues, resulting in the tolerance to subsequent high dose irradiation.

Congenital hypothyroidism usually has no specific clinical symptoms in the neonatal period, which can be detected early through newborn screening, and early thyroid hormone replacement therapy can improve the prognosis.Congenital hypothyroidism is associated with the thyroid hypoplasia, thyroid hormone synthesis disorder, low response of thyroid or target organs and central hypothyroidism.With the development of genomics and second-generation gene sequencing, more and more monogenic mutations have been reported to be associated with this disease.The review of CH caused by monogenic mutation is aimed at comprehensively assessing the condition of neonates with CH, providing individualized treatment, guiding long-term follow-up and improving prognosis.

Dental resin materials have been widely used in the treatment of dental defects. However, the polymerization shrinkage of the resin materials tends to cause microleakage and accumulation of bacterial plaque, which leads to secondary dental caries. Endowing dental resin with antibacterial properties is an important way to solve this problem. Adding antibacterial agents to dental resin is the main method to give it antibacterial properties. Antimicrobial agents are mainly divided into three types: release type, non-release type and mixed type. In terms of antibacterial effects, the selection and addition of antibacterial agents will affect the antibacterial and mechanical properties of dental resin materials; and the long-term antibacterial effect of antimicrobial agents in the oral cavity remains to be verified; as antimicrobial agents or other environmental factors can lead to drug resistance and even dormant persistent bacteria. In recent years, researchers have been committed to improving the antibacterial effect by modifying antibacterial agents. The sustained release of antimicrobial agents via carriers is also the main research direction. This paper reviews the research progress on the antibacterial properties of dental resin materials.