AIM:To study the effects of antagonistic peptides binding specifically with the first and second extracellular loops (ECL1 and ECL2) of C-C chemokine receptor 5 (CCR5) on the colitis rats induced by trinitrobenzenesulfonic acid (TNBS) and the mechanisms.METHODS:The colitis model of SD rats was induced by TNBS (100 mg/kg).The effects of 2 antagonistic peptides at different doses (ECL1:25, 35 and 45 mg/kg;ECL2:15, 25 and 35 mg/kg) on the model rats including the changes of disease activity index (DAI), colon macroscopic damage index (CMDI) and histological grading were observed.The mRNA and protein expression levels of TNF-α and COX-2 in the colonic mucosa were detected by real-time PCR and Western blot, respectively.RESULTS:Compared with model group, the changes of DAI, CMDI and histopathological injury of the rats treated with ECL2 antagonistic peptide HY at an appropriate dose were significantly reduced (P<0.05), and the protein and mRNA expression levels of TNF-α and COX-2 were significantly decreased (P<0.05).However, the effects of ECL1 antagonistic peptide GH on all scores and the expression levels of TNF-α and COX-2 were not obvious.CONCLUSION:ECL2 antagonistic peptide HY relieves TNBS-induced colitis in SD rats via down-regulating the expressions of TNF-α and COX-2 in the colonic mucosa, while the effect of ECL1 antagonist peptide GH was not obvious.

Objective To observe the effect of sling exercise therapy (SET) on rehabilitation after knee arthroplasty. Methods 46 patients after knee arthroplasty were randomly divided into experimental group (n=23) and control group (n=23). The control group received continuous passive motion (CPM) training, while the experimental group received SET. They were evaluated with range of motion (ROM) of the knee, Hospital for Special Surgery Knee Score (HSS) and posture control ability before, 15 days and 3 months after operation. Results 15 days after operation, the maximal passive knee flexion was 6.0° more in the SET group than in the CMP group (95%CI=0.9°~11.2°; P<0.01), and the maximal active knee flexion was 5.7° more in the SET group than in the CMP group (95%CI=0.4°~9.1°; P<0.01); however, there was no significant difference in the maximal active knee extension, the maximal passive knee extension, HSS and posture control ability between 2 groups (P>0.05). 3 months after operation, there was no significant difference in all the items between 2 groups (P>0.05). Conclusion Compared with CPM, SET might be more effective on increasing knee ROM in the short-term, and could be used as an effective intervention for patients after knee arthroplasty at the early stage.

Objective Retrospectively analysis on death cases related with aortic dissection provides support for further forensic investigation on such cases. Methods 44 Cases on aortic dissection are collected from the Forensic Medical Center in Kunming Medical University from 2002to2017.Statistic anaylisis was applied to each case's general information,clinical stage,clinical manifestation,risk factors,pathological type,rupture state,and direct case of death. Results The results showed that aortic dissection occurs moslty in middle age male who ranges from 40 to 49 years old. Most cases were aute aortic dissection, and the death rate was the highest in winter and the lowest in spring. Furthermore, pain is shown to be the most common symptom. Atherosclerosis is a critical factor that contributes to the occurance of aortic dissection. In general, type A aortic dissection occurs more frequently than type B. The rupture, located in ascending aorta, often is in a transverse shape. Cardiac tamponade is the primary cause of death.Conclusion Definite initial symptoms arises before aortic dissection rupture and always show many high-risk factors. It is beneficial to forensic identification of the relation between aortic dissection and injury or medical behavior should be considered carefully.

Objective: To analyze the prevalence of comorbidity of spinal curvature abnormality and malnutrition among primary and secondary school students aged 10-18 years in Tianjin in 2023, so as to provide scientific basis for the combined prevention of common diseases and multiple diseases among students and the construction of school health system. Methods: In September to October 2023, 31 884 primary and secondary school students aged 10 to 18 years in Tianjin were selected using stratified cluster random sampling. Abnormal spinal curvature in children and adolescents was assessed by Sereening of Spinal Curvature Abnormality of Children and Adolescents, while stunting, wasting, overweight, and obesity were determined according to the Screening for Malnutrition among Schoolage Children and Adolescents and Screening for Overweight and Obesity among Schoolage Children and Adolescents. The χ2 test was used to compare betweengroup differences in coprevalence, and multiple Logistic regression models were used to analyze the risk of different comorbidity types in different clusters. Results: The coprevalence of spinal curvature abnormality and malnutrition among primary and secondary school students in Tianjin was 1.6%, which was higher for girls than boys (1.8%, 1.4%), higher (2.5%) for senior high schools than for junior high schools and elementary schools (2.0%, 0.5%), and higher in rural than in urban areas (2.1%, 1.1%) (χ2=9.45, 141.92, 46.94, P<0.05). Multiple Logistic regression models showed that junior high school girls had a higher risk of incorrect posture comorbid with stunting and wasting (OR=4.52, 95%CI=1.84-11.06) and incorrect posture comorbid with overweight and obesity (OR=2.67, 95%CI=1.74-4.10) than boys, and that scoliosis/sagittal spinal abnormality comorbid with stunting and wasting (OR=0.10, 95%CI=0.02-0.44) risk was lower than that of boys, senior high school girls had a lower risk of scoliosis/sagittal spinal abnormality comorbid with overweight and obesity (OR=0.27, 95%CI=0.11-0.66) (P<0.05). Conclusions The coprevalence of spinal curvature abnormality and malnutrition is specific among primary and secondary school students in Tianjin, and the comorbidity type varies by gender and education stage. There is a need to increase prevention and control of spinal curvature abnormalities in school health working, intensive screening of key populations, and timely intervention.

Objective This study aimed to explore the effect of peripheral blood mesenchymal stem cells combined with porous absorbable gelatin sponge/self assembling peptide composite scaffolds on SD rat femoral con-dyle bone defect reconstruction and provide a new strategy for the repair of bone defects. Methods 30 female SD rats,8W age,were randomly divided into 3 groups,10 every group.The group A was blank control group,group B was porous absorbable gelatin sponge/self assembling peptide composite scaffold group,and group C was periph-eral blood mesenchymal stem cells combined with porous absorbable gelatin sponge/self assembling peptide compos-ite scaffold group. The effect of osteogenesis was observed by paraffin section,hematoxylin eosin staining,X-ray examination,and Micro-CT scanning in 3 dimensional reconstruction of femoral condyle defect. Results Imaging examination showed that the experimental group had better osteogenesis effect. Histological examination showed that a lot of new bone tissue was found in group C,while only a small amount of new bone was found in the group of A and B. Conclusions The experiment shows that peripheral blood mesenchymal stem cells as the seed cells for tissue engineering,combined with porous absorbable gelatin sponge-self assembling peptide has better ability to repair bone defects,and has good application prospect,which is worthy of further research.

Objective:To explore the effect of conducting core stability training (CST) on an unstable supporting surface using thoracolumbar fracture patients with an incomplete spinal cord injury.Methods:Forty thoracolumbar fracture patients with incomplete spinal cord injury were randomly divided into an experiment group and a control group, each of twenty. Both groups received 30 minutes of CST five times per week for 8 weeks. The patients in the control group were trained on a stable supporting surface while those in the experiment group used an unstable surface. Evaluations were conducted before and after the 8-week intervention. Gait and static balance data were collected and analyzed using 3D motion analysis software and an EAB-100 active balancer.Results:After the intervention, the average stride length and comfortable walking speed of the experimental group were both significantly better than the control group′s averages. Moreover, the path length, circumferential area, rectangular area and effective value area of the Romberg rate were all significantly better, on average, in the experiment group, as was the average displacement of the deflection center with the eyes closed in static balance.Conclusions:An unstable supporting surface is superior to a stable one for conducting CST after thoracolumbar fracture with incomplete spinal cord injury. The effect may be due to improved nonvisual postural control.

Objective:To analyze the characteristics of eyes with congenital optic disc pits (ODPs) through multimodal imaging.Methods:A cross-sectional study was conducted.Thirty-eight patients (38 eyes) diagnosed with congenital ODPs in the Second Hospital of Hebei Medical University from January 2009 to January 2020 were enrolled.A comprehensive summary analysis of the imaging results including fundus photography, spectral domain-optical coherence tomography (SD-OCT), infrared imaging, fundus autofluorescence (FAF), fluorescein fundus angiography (FFA) and indocyanine green angiography (ICGA) was performed.This study protocol adhered to the Declaration of Helsinki and was approved by an Ethics Committee of The Second Hospital of Hebei Medical University (No.2021-P011). Written informed consent was obtained from each subject prior to any medical examination.Results:Among the 38 eyes, there were 32 eyes with ODPs located in or below the temporal side of optic disc, 4 eyes with ODPs located above the temporal side of optic disc, and 2 eyes with ODPs located at the center of optic disc, which were round or quasi-circular pale depression, and dark red eminences with clear or unclear boundaries between milk spots were found in 29 eyes with optical-disc macular degeneration (ODP-M) by fundus photography.SD-OCT examination showed that the structure of lamina cribrosa in the lesion area in all ODPs patients was incomplete, which presented a dark area with no tissue reflection, and the fissure led to the deep optic nerve.Fluid was found in the outer nuclear layer in all ODP-M patients, and there were 27 eyes with fluid in the inner nuclear layer, 13 eyes in the ganglion cell layer, and 4 eyes under the inner limiting membrane.Among the 29 eyes with ODP-M, there were 21 eyes with retinoschisis in outer layer, 27 eyes with neuroepithelial detachment.In the 27 eyes with neuroepithelial detachment, spot-like high reflection and reduced or disappeared ellipsoid band reflectance were seen above the neuroepithelium in 18 eyes.In infrared images, there were circular or quasi-circular low-reflection areas in the temporal side of the optic disc, and the lesion of ODP-M eyes presented low-reflection areas.FAF examination showed that in 27 eyes with ODP-M, there was a hypofluorescent region at the posterior pole consistent with the lesion range, among which, there was a granular or sheet-like hyperfluorescence at the center of the hypofluorescent region in 18 eyes.FFA showed that the optic disc depression in the arterial phase of patients was in a localized hypofluorescence state.During the venous phase, fluorescein dye extravasation along the temporal side of the optic disc could be found.A strong fluorescent arc with unclear boundaries at the temporal edge of the optic disc was formed in the late stage of angiography.Among the 29 eyes with ODP-M, the area of the macular lesion showed hyperfluorescence during the late stage of angiography in 27 eyes with neuroepithelial detachment, and no extension of dye toward the macula was found.ICGA showed that the optic disc depression of ODPs patients presented a localized hypofluorescence, and the lesion showed hyperfluorescence in 27 of the 29 ODP-M eyes with neuroepithelial detachment.Conclusions:Multimodal imaging can be helpful to realize the early diagnosis, etiology analysis of ODPs and make treatment plan.

Objective: To analyze the hotspots, frontiers, and future research trends related to puberty development among children and adolescents from 2013 to 2022, and to provide a reference for subsequent research related to puberty development. Methods: Data related to puberty development from 2013 to 2022 were retrieved from the Web of Science core collection with the search formula "puberty timing (title) OR puberty development (title) OR pubertal timing (title) OR pubertal development (title) OR puberty timing (abstract) OR puberty development (abstract) OR pubertal timing (abstract) OR pubertal development (abstract)". The CiteSpace was used for visual analysis. Results: A total of 6 684 publications were obtained and an upward trend could be seen in the number of publications in the field of puberty development in the last 10 years. Researchers with a high number of publications were Juul Anders, Brix Nis, and Ernst Andreas, in addition, the United States had the highest number of publications ( 2 125 ) and the highest betweenness centrality (0.23) in this field. In the last decade, research hotspots had focused on the timing of pubertal initiation, biological mechanisms of pubertal development, and sex differences in pubertal development. Research on environmental endocrine disruptors and the mechanisms of pubertal development were at the forefront of research and future research trends. Conclusion Scholars can refer to the research hotspots and research trends in this field and focus on the issues related to environmental endocrine disruptors and pubertal development mechanisms.

Objective: To investigate the prevalence of Internet addiction and depression of students, and to analyze the co-occurrence and trend, so as to provide a theoretical basis for prevention and controlling measures of Internet addiction and depression. Methods: A total of 6 317,7 152,81 808,71 180 and 89 932 students aged 10 to 24 years from 12 leagues (103 banners) in Inner Mongolia Autonomous Region were selected by stratified random cluster sampling in September each year from 2017 to 2021. The Internet Addiction Scale and the Central for Epidemiologic Studies Depression Scale(CES-D) was used to measure Internet addiction and depression. And the annual inspection rate, group difference and annual change trend in students were calculated. Multivariate linear regression and restricted cubic spline analysis were used to estimate the linear and non linear associations between Internet addiction and depression in students. Results: The Internet addiction proportion in students gradually decreased from 4.1% in 2017 to 2.1% in 2020, but increased to 3.9% in 2021. And the depressive symptoms proportion increased from 20.9% in 2017 to 28.0% in 2020 and 27.0% in 2021. The detection rate of Internet addiction and depression comorbidities remained at 1.8% to 2.5 %. The Internet addiction proportion in boys was higher than that in girls( χ 2=42.82， P <0.05). The depressive symptoms prevalence in girls was higher than that in boys( χ 2= 553.90， P <0.05). Taking reversal in prevalence of Internet addiction in urban and rural areas was observed in 2019. The detection rates of depressive symptoms and comorbidity were higher in urban areas than these in suburban counties on the whole, and the difference showed a trend of decreasing or even equalizing year by year. Internet addiction was positively correlated with depressive symptoms score ( B=1.67, 95%CI =1.64-1.71), the proportion of depressive symptoms ( OR=1.39, 95%CI =1.38-1.41) and the proportion of major depressive symptoms ( OR=1.35, 95%CI =1.33-1.36) among students in 2021 ( P <0.05). An N-shaped curve was found in the significant nonlinear associations between internet addiction and depression across sex, region and school stage. Conclusion Internet addiction and depression in students show significant linear and non-linear associations, which are consistent in different sexes, regions and school stages. Therefore, relevant measures should be made and implemented in each region, especially in suburb areas, so as to prevent the increasingly development of adolescents and children s Internet addiction and depression.

Objective: To explore the current status and progress of regional school health work to provide policy reference for school health improvement. Methods: Survey data on school health work in Tianjin from 2019, 2021 and 2023 was used. School health staff allocation and expenditure of the health administrative department, CDC and education department, as well as the annual implementation of health education, prevention and control of common diseases and infectious diseases, sports activities and food nutrition in primary and secondary schools were analyzed. Statistical analysis was conducted using KruskalWallis test, Chisquare test, and Fishers exact test. Results: The number of school health staff in the health commissions and education departments from 2019, 2021 and 2023 was relatively stable. Parttime staffs were often employed by health commissions while fulltime staffs were mainly employed by education departments. The number of school health staff at CDCs increased gradually (H=12.65, P<0.01). School health expenditure of administrative departments and schools in 2021 and 2023 increased significantly compared with that in 2019 (H=22.28, 23.75, P<0.05). More than 95% of schools set up clinics or health care rooms, and about 97% of schools had school health technicians or health teachers. More than 90% of schools had health education courses over 4 hours per semester. The rate of mental health education increased by year (86.87%, 89.91%, 96.30%, Z=2.40，P<0.05). Lack of courses regarded safety emergency and risk avoidance, growth and development, and adolescent health education. The provision rate of psychological counseling services (89.00%, 97.25%, 100.00%) and psychological problem prevention and control (56.12%, 71.56%, 81.48%) also increased by year (Z=3.83, 3.96, P<0.01). The implementation rates of prevention and control of poor vision, dental caries, overweight and obesity were all higher than 80%, and the prevention and control rate of abnormal spinal curvature showed an increasing trend (38.78%, 77.06%, 72.22%, Z=4.87, P<0.01). More than 90% of schools met the standard for physical education class hours, and the proportion of schools conducting at least 30 minutes of recess physical activities every day increased year by year (65.00%, 80.73%, 85.98%, Z=3.59, P<0.01). All schools did not have shops. Conclusions School health work in Tianjin is effective and constantly developing. It is necessary to continue to increase the investment of human resources and expenditure in school health, explore the approaches of cooccurrence and prevention of common diseases, and improve the school sports and nutrition environment.