BACKGROUND:Halo gravity traction is a pre-operative traction method recognized by many scholars,but most of them rely on clinical observation and lack finite element analysis. OBJECTIVE:To explore the best traction force of Halo gravity traction on Lenke 3 scoliosis by finite element method and to provide a theoretical basis for clinics from a biomechanical point of view. METHODS:The CT images scanned by patients with scoliosis were processed by reverse modeling,and a finite element model was established.The validity of the model was verified by taking normal segments(T1-T4 vertebral bodies).Five groups of different stress conditions were set on the lumbar-thoracic scoliosis model to simulate the correction of patients under different traction forces.In all five groups,the lower surface of L5 was completely restrained,and different traction forces were applied to the upper surface of T1 along the positive direction of the Z axis(the opposite direction of gravity),which were 50,100,150,200,and 250 N,respectively.The displacement of the scoliosis spine,Cobb angle change of the main bending,elongation of the spine,and Von Mises stress were compared under different traction forces. RESULTS AND CONCLUSION:(1)When the Halo gravity traction force was 150 N to 200 N,the reduction of the Cobb angle of the main bending was 69.4%to 88.9%of the maximum reduction;the elongation of the Z axis was 69.4%to 85.9%,and the stress was 63.6%to 82.9%of the maximum stress.(2)When the traction force was greater than 200 N,the reduction of the Cobb angle and the elongation of the Z axis did not change obviously,but the stress value increased sharply.At this time,the distance from the centroids of T6,T7,and T8 to the vertical line of L5 was the most obvious.(3)When the Halo gravity traction force was 150 N to 200 N,the correction effect on this type of patient was the best—the reduction of Cobb angle and the elongation of the Z axis were better without the sharp increase in stress.(4)It has certain theoretical support for clinical correction and can ensure the safety of patients when scoliosis is corrected to a large extent.

Background and objective Neoantigen reactive T cell(NRT)has the ability to inhibit the growth of tumors expressing specific neoantigens.However,due to the difficult immune infiltration and the inhibition of tumor micro en-vironment,the therapeutic effect of NRT in solid tumors is limited.In this study,we designed NRT cells(7×19 NRT)that can express both interleukin-7(IL-7)and chemokine C-C motif ligand 19(CCL19)in mouse lung cancer cells,and evaluated the difference in anti-tumor effect between 7×19 NRT cells and conventional NRT cells.Methods We performed next-generation sequencing and neoantigen prediction for mouse Lewis lung carcinoma(LLC),prepared RNA vaccine,cultured NRT cells,constructed retroviral vectors encoding IL-7 and CCL19,transduced NRT cells and IL-7 and CCL19 were successfully ex-pressed,and 7×19 NRT was successfully obtained.The anti-tumor effect was evaluated in vivo and in vitro in mice.Results The 7×19 NRT cells significantly enhanced the proliferation and invasion ability of T cells by secreting IL-7 and CCL19,achieved significant tumor inhibition in the mouse lung cancer and extended the survival period of mice.The T cell infiltration into tumor tissue and the necrosis of tumor tissue increased significantly after 7×19 NRT treatment.In addition,both 7×19 NRT treatment and conventional NRT treatment were safe.Conclusion The anti-solid tumor ability of NRT cells is significantly enhanced by the arming of IL-7 and CCL19,which is a safe and effective genetic modification of NRT.

Objective To study the biomechanical differences between hollow compression screws and shape-memory alloy staples in triple arthrodesis internal fixation and to provide references for the clinical application of shape-memory alloy staples.Methods Two-dimensional(2D)computed tomography(CT)foot data from a patient with severe horseshoe foot stiffness were selected,and a triple arthrodesis model was established using Mimics and Geomagic software.A geometric triple arthrodesis internal fixation model was established using SolidWorks 2021 software.Four fixation schemes(A,B,C,and D)were established according to the type and combination of fixed screws(hollow compression screws and shape-memory alloy riding nails).The biomechanical characteristics of models with different internal fixation schemes under neutral physiological loading were simulated and analyzed using ABAQUS software.Results The maximum end-face displacements of the fused surfaces of the talocalcaneal talonavicular and calcaneocuboid joints in the internal fixation model of scheme D were greater than those in schemes A,B,and C.The differences between the medial and lateral displacements of the fused surfaces of the talonavicular and calcaneocuboid joints in the internal fixation model of scheme D were 13.10％and 13.60％,respectively.The fused surface displacements were closer to the parallel displacements than those in the other three fixation schemes.The von Mises stresses were greater than those of schemes A,B,and C.Conclusions The application of scheme D(internal fixation at fusion surfaces of the talonavicular and calcaneocuboid joints with staples and at fusion surfaces of the talocalcaneal joints with compression hollow screws)provides stability at fusion surfaces of the internal fixation after triple arthrodesis surgery with near-parallel micromovement,which produces appropriate fusion stresses to make contact at the fusion end closer,promote the growth of bone scabs,and achieve better fusion results.

Objective: To understand the social adaptation in the association between attitude towards parents with academic anxiety among middle school students in Chongqing, so as to provide a basis and thinking method for theoretical framework of family education and youth development. Methods: Convenient and clustering sampling method was used to select 34 097 middle school students aged 13-18 years during September to November 2023. All the participants were investigated with self designed questionnaire, Social Adaptability Scale and Mental Health Test. The mediating effect of social adaptability in the relationship between students attitudes towards their parents academic anxiety was evaluated by using Logistic regression analysis and structural equation model. Results: The proportion of high school students in Chongqing with academic anxiety was 48.80%. Academic anxiety differed significantly by sex, academic grade, attitude towards parents, and social adaptability ( χ 2=948.45, 173.92, 537.51, 4 770.04, P < 0.01). The results of Logistic regression analysis showed that positive attitudes towards parents were positively correlated with moderate academic anxiety ( OR=1.13, 95%CI =1.08-1.18) and high academic anxiety ( OR=1.14, 95%CI =1.09-1.19) ( P < 0.05 ). The results of the mediation effect analysis showed that positive attitude of middle school students towards their parents negatively predicted academic anxiety ( β= -0.12 , P <0.01), but when social adaptation ability was used as a control variable, the original negative relationship between the positive attitude towards parents and academic anxiety of middle school students changed ( β=0.02, P <0.01), and social adaptation ability played a masking effect in the relationship. The social adaptation ability of middle school students played a mediating role in the relationship between their positive attitudes towards their parents and academic anxiety, with a mediating effect of -0.63. Conclusions The attitude of middle school students towards their parents will directly affect academic anxiety, and also have an indirect impact on academic anxiety through social adaptability, but there is a cover effect. Pay more attention to family education and actively focus on students social adaptability can contribute to improve the mental health level of adolescents.

Objective To investigate the association between famine exposure in different life cycles and the risk of central obesity. Methods A total of 2234 spermanent residents were recruited to participate in the China Multi-Ethnic Cohort (CMEC) Study ,they were grouped into four birth cohorts of fetal-exposed (born between January 1,1959, and December 31,1961,95 cases), childhood-exposed (born between January 11,949, and December 31,1958,533 cases), adolescence/adult-exposed (born between January 1,1931, and December 31,1948,256 cases),unexposed cohorts（born after January 1, 1975，871 cases).we used logistic regression model to assess the effect of famine exposure on central obesity in adulthood. Results After adjusting for confounding factors, females in the fetal/infant exposure group（OR=3.283,95%CI：1.472～7.321,P＜0.001）、childhood- exposed group (OR=3.557,95%CI：2.374～5.313,P＜0.001) and adolescence/adult-exposed group (OR=5.785，95%CI：3.536～9.492，P＜0.001) had a higher risk of adult central obesity than the control group.After excluding the subjects with coronary heart disease、cancer、diabetes、stroke or obesity, sensitivity analysis was carried out. The risk of central obesity increased in the female / fetal、childhood、adolescent / adult exposure group,which was unfound in males. Conclusion Severe famine exposure in fetal/infant、childhood and adolescence/adulthood can increase the risk of central obesity in adulthood in females. Therefore, the prevention and control of central obesity in female should start from the early life.

Objective:To explore whether the adoption of high-flow nasal cannula (HFNC) as an initial oxygen therapy in emergency department (ED) could reduce the intubation rate and improve the clinical outcomes of patients with dyspnea and hypoxemia compared with conventional oxygen therapy (COT).Methods:A perspective single-center randomized controlled trial was conducted in the First Affiliated Hospital of Zhengzhou University from October 1, 2019 to September 30, 2020. A total of 210 eligible patients with acute dyspnea and hypoxemia in ED were recruited and randomized (in 1:1) to receive HFNC or COT for 1 h immediately after the grouping. The primary outcome was the rate of intubation within 24 h. The secondary outcomes included total intubation rate, escalation of breathing support method, patients’ disposition, length of ICU stay and hospital mortality. Continuous outcomes were analyzed by independent samples t test or Mann-Whitney U test according to the data distribution. Discontinuous outcomes were compared with the Chi-square test. Kaplan-Meier curve analysis was performed for 60-day survival. Results:Finally, 105 patients were recruited in each group. HFNC reduced the intubation rate within the first 24 h (4.8% vs. 14.3%, P = 0.019) and the rate of patients escalated to upgrade oxygen therapy (34.3% vs. 53.3%, P = 0.005), but did not affect the total intubation rate during the whole attendance ( P = 0.509). In ED, HFNC helped more patients to achieve the targeted saturation of pulse oxygen (90.5% vs. 78.1%, P = 0.02), and reduced respiratory rate (RR) to < 25 breaths per min (68.6% vs. 49.0%, P = 0.004), but did not affect the length of hospital stay, hospital mortality and 60-day survival rate ( P > 0.05). Conclusions:Initial application of HFNC in ED could reduce the intubation rate within 24 h, decrease the rate of escalation of oxygen therapy, improve oxygenation and relieve dyspnea.

Objective To investigate dynamic response of the finite element model of Lenke3 type scoliosis. Methods The finite element model was established based on CT scanning images from a patient with Lenke3 type scoliosis, and validation of the model was also conducted. Modal analysis, harmonic response analysis and transient dynamic analysis were carried out on the model. Results The first order natural frequency of this model was only 1-2 Hz.The amplitude of the finite element model was the largest at the first natural frequency. At the same resonance frequency, the amplitude of the thoracic curved vertebra was larger than that of the lumbar curved vertebra.The amplitude from T6 vertebra to L2 vertebra decreased successively. Conclusions The degree of spinal deformity may affect the perception of spine vibration, and the higher the degree of spinal deformity, the higher the sensitivity to vibration. The first natural frequency is most harmful to Lenke3 type scoliosis patients. Under cyclic loading, the thoracic curved vertebra is more prone to deformation than the lumbar curved vertebra. The closer to T1 segment, the greater the amplitude of the vibration is.

【Objective】 To investigate the current situation concerning volume control of red blood cells in additive solution produced by blood service in Chongqing, and to lay a foundation for promoting the homogenization of preparation process of red blood cells in additive solution. 【Methods】 A questionnaire was designed to investigate the factors related to the preparation of red blood cells in additive solution. The questionnaire was sent by Chongqing Association of Blood Transfusion via E-mail to 18 blood services in the city, and the collected data was sorted, revised and analyzed by research team. 【Results】 A total of 18 blood services(including 1 blood center + 1 sub-center, 6 central blood stations and 11 central blood banks) returned the questionnaires. The results showed that there were differences among blood services across Chongqing, regarding the centrifugal parameters during preparation, the operation mode and monitoring situation of the capacity control during preparation, and the formulation of the capacity standard of red blood cells in additive solution etc. 【Conclusion】 The preparation process of red blood cells in additive solution, produced by Chongqing blood services, should be further standardized, and the capacity control method of this product in Chongqing should be gradually unified to achieve regional homogeneity and to ensure blood safety.

Objective:To improve accuracy of prediction amount of length of gastric tube placed through nose and reduce occurrence of adverse events thorough clinical observation of measurement of length of nasogastric tube placement in critically ill children.Methods:Using the convenient sampling method, critically ill children who were hospitalized and needed a nasogastric tube in Pediatric Intensive Care Unit (PICU) of Beijing Children's Hospital Affiliated to Capital Medical University were selected from April to September 2019. The prediction method of "nos-ear-xiphoid (NEX) increased by 5 cm" (NEX+5 cm) was adopted. The values of placed length in this study were collected and compared with those predicted by traditional measurement method (namely NEX) , improved "nose-ear-mid-umbilicus" (NEMU) and formula method.Results:A total of 52 critically ill children were enrolled in this study. The length of placed nasogastric tube was 31.5 (28.3, 35.8) cm, and 43 cases (82.7%) were determined to be qualified by X-ray. The length of gastric tube required to be placed in children was 27.0 (24.1, 31.0) cm according to the NEX method, and the length of gastric tube required to be placed in children was 26.1 (22.5, 29.0) cm measured by the formula method. Both were shorter than that measured by NEX+5 cm, and the differences were statistically significant ( P<0.01) . The NEMU method measured the length of gastric tube to be inserted into the child to be 31.0 (28.3, 36.0) cm. Compared with the length measured by NEX+5 cm, and the difference was not statistically significant ( P>0.05) . Conclusions:This study uses NEX+5 cm to predict the actual length of the gastric tube inserted through the nose. The accuracy is relatively high and the operation method is simple. It is necessary to consider individual differences in clinical applications, especially the large variability in infants and young children. After catheterization, abdominal ultrasound, X-ray and other auxiliary examination methods should be used to determine the location of catheterization, and individualized catheterization programs should be given to children according to different therapeutic objective.

Objective:To explore the key genes and pathways that may play an important role in the pathogenesis of acne by bioinformatics analysis.Methods:GSE6475 and GSE53795 datasets were collected from GEO database, and 18 acne lesions tissues and 18 normal skin tissues were compared. David database was used to analyze the gene ontology (GO) and the key pathway (Kyoto Encyclopedia of genes and genomes, KEGG) of the differential genes, to establish the protein interaction network of the differential genes, and to obtain the most relevant key genes and important clusters.Results:A total of 314 up-regulated genes and 62 down-regulated genes were filtered from those GEO profiles. KEGG pathway analysis showed that these differential genes were mainly enriched in Staphylococcus aureus infection, osteoclast differentiation, pentose and glucuronate interconversions. In addition, 379 nodes and ten key genes (CXCL8, PTPRC, IL1B, ITGB2, CXCR4, ICAM1, CCR5, SELL, C3AR1 and PLEK) were screened out by protein interaction network.Conclusions:The key genes and pathways identified in this study may be new targets for intervention in the development of acne.