Objective: To analyse the influence path of family economic status on adolescent depressive symptoms, and to explore the chained mediation role of peer relationship and self satisfaction, as well as the moderating effect of the parent-child relationship, so as to provide a theoretical basis for the prevention and control of adolescent depressive symptoms. Methods: Data were obtained from the Database of Youth Health （DYH） in the National Population Health Science Data Center, and a total of 11 277 samples were included. Questionnaires were used to obtain information on family economic status, peer relationship, self satisfaction, parent-child relationship and depressive symptoms. Spearman correlation analysis was used to examine correlations among variables. Hierarchical linear regression analysis was used to analyze effects of family economic status and parent-child relationship on depressive symptom scores. The Process macro program was adopted to test the chained mediating effects of peer relationship and self satisfaction and the moderating effect of parent-child relationship. Results: The prevalence rate of depressive symptoms among adolescents was 24.2%. The prevalence rates of depressive symptoms significantly differed among adolescents with different family economic status and places of residence( χ 2=210.12, 4.18, both P ＜0.05). Adolescents with depressive symptoms had significantly lower scores on peer relationship, self satisfaction, and parent-child relationship compared to those without depressive symptoms ( t = 27.76 , 42.43, 31.12, all P ＜0.05). Family economic status were negatively correlated with adolescent depressive symptom scores ( B =-0.12, P <0.05).Parent-child relationship was negatively correlated with depressive symptom scores ( B = -0.02 , P < 0.05 ). After introducing the parent-child relationship, the negative effect of family economic conditions was reduced ( B = -0.08, P ＜ 0.01). Family economic conditions affected depressive symptoms through the chained mediating pathway involving peer relationship ( B = 2.07 ) and self satisfaction ( B =3.88)(both P <0.05). The parent-child relationship moderated this pathway: under conditions of high quality parent child relationship, the effect of family economic status on peer relationships was weaker ( B = 0.15); under low quality parent-child relationship, the positive effect of family economic status on peer relationships was enhanced ( B = 1.15 ) (both P ＜0.01). Conclusions Family economic status exert both direct and chain mediating effects on adolescent depression, and high quality parent-child relationship can play a protective moderation role. For economically disadvantaged families, it is critical to synergistically enhance parent-child relationship and social support in order to reduce depression risk among adolescents.

Objective　To explore the characteristics of toxic heavy metal pollution in atmospheric PM2.5 (Particulate matter 2.5) during winter in Nanning City and to evaluate the health risks for the population. Methods　Atmospheric PM2.5 samples were continuously collected in the urban areas of Nanning from January to February 2019. The concentrations of seven toxic heavy metals, including cadmium (Cd), arsenic (As), chromium (Cr), lead (Pb), nickel (Ni), mercury (Hg), and manganese (Mn) in atmospheric PM2.5 were analyzed by X-ray fluorescence spectrometry. The pollution characteristics of toxic heavy metals were studied by geo-accumulation index and enrichment factor methods, and their health risks to children and adults were assessed using the health risk assessment model of the United States Environmental Protection Agency. Results　The mass concentration of atmospheric PM2.5 in Nanning in winter 2019 was (44±29) μg/m3, which was generally at a low level. Different degrees of pollution were found for Hg, Cd, As, Cr, and Pb in PM2.5, with Hg and Cd being more seriously polluted. Hg and Cd were highly enriched in PM2.5, followed by Pb with moderate enrichment. These three elements mainly originated from man-made pollution. As, Cr and Ni were mildly enriched and affected by both natural and anthropogenic sources. The non-carcinogenic risks were in the order of As>Pb>Hg>Cr>Cd>Mn>Ni. The total non-carcinogenic risks for the three populations were all less than 1, which is within acceptable limits. The carcinogenic risks were ranked as Cr>As>Cd>Ni, with Cr, As, and Cd posing carcinogenic risks to children and adults ranging from 1×10-6 to 1×10-4. Moreover, the total carcinogenic risks of heavy metals (Cr, As, Cd, and Ni) were higher than 1×10-4 for children, indicating a potential carcinogenic risk. Conclusions　The mass concentration of PM2.5 and heavy metal elements in Nanning City during the winter of 2019 was relatively low, but the pollution of heavy metals still exists. The non-carcinogenic risk of heavy metals is within an acceptable range, but the carcinogenic risk poses a potential danger to children.

Objective:To explore the diagnostic value of whole blood cell parameters logistic regression model for radiation injury on radiation workers by comparing the differences of whole blood cell parameters between occupational radiation injury population and occupational health examination population.Methods:In February 2023, 184 radiation workers who received occupational health examinations in our hospital and occurrenced chromosome aberration from July 2021 to July 2022 were retrospectively selected as the radiation injury group. And other 184 radiation workers encountered in the same period without chromosome aberration occurrence were selected as the control group. Collected whole blood cell parameters from two groups of research subjects, conducted comparative analysis, constructed a logistic regression model, and evaluated the diagnostic value of the logistic regression model for radiation injury on radiation workers by receiver operating characteristic curve (ROC) and area under curve (AUC) . In addition, with the same standard, 60 radiation workers with chromosome aberration and 60 radiation workers without chromosome aberration from August 2022 to January 2023 were included in the validation queue to validate the logistic regression model.Results:Neu_X, Neu_Y, Neu_Z, Lym_X, Lym_Y, Lym_Z, Mon_X, Mon_Y, Mon_Z, Micro, MCHC in the radiation injury group were significantly higher than those in the control group, and the difference was statistically significant ( P<0.05) . And MCV and Macro in the radiation injury group were lower than those in the control group, and the difference was statistically significant ( P<0.05) . Moreover, logistic regression analysis showed that Lym_X, Lym_Y, Lym_Z, MCHC, Micro were all independent risk factors for diagnosing radiation injury on radiation workers ( OR=1.08、1.02、0.99、1.06、51.32, P<0.05) . ROC curve analysis showed that the AUC, sensitivity, specificity, and accuracy of the logistic regression model based by Lym_X, Lym_Y, Lym_Z, MCHC and Micro in diagnosing radiation injury on radiation workers were 0.80, 85.9%, 65.8% and 75.9% respectively. The validation queue verified the logistic regression model and the AUC, sensitivity, specificity, and accuracy of the logistic regression model were 0.80, 81.7%, 71.7% and 76.7% respectively, the model fitted well. Conclusion:Radiation damage can cause changes in multiple whole blood cell parameters of radiation workers. The logistic regression model based by Lym_X, Lym_Y, Lym_Z, MCHC and Micro showed good diagnosis ability and can be used for the screening of radiation injury on radiation workers.

Objective:To explore the diagnostic value of whole blood cell parameters logistic regression model for radiation injury on radiation workers by comparing the differences of whole blood cell parameters between occupational radiation injury population and occupational health examination population.Methods:In February 2023, 184 radiation workers who received occupational health examinations in our hospital and occurrenced chromosome aberration from July 2021 to July 2022 were retrospectively selected as the radiation injury group. And other 184 radiation workers encountered in the same period without chromosome aberration occurrence were selected as the control group. Collected whole blood cell parameters from two groups of research subjects, conducted comparative analysis, constructed a logistic regression model, and evaluated the diagnostic value of the logistic regression model for radiation injury on radiation workers by receiver operating characteristic curve (ROC) and area under curve (AUC) . In addition, with the same standard, 60 radiation workers with chromosome aberration and 60 radiation workers without chromosome aberration from August 2022 to January 2023 were included in the validation queue to validate the logistic regression model.Results:Neu_X, Neu_Y, Neu_Z, Lym_X, Lym_Y, Lym_Z, Mon_X, Mon_Y, Mon_Z, Micro, MCHC in the radiation injury group were significantly higher than those in the control group, and the difference was statistically significant ( P<0.05) . And MCV and Macro in the radiation injury group were lower than those in the control group, and the difference was statistically significant ( P<0.05) . Moreover, logistic regression analysis showed that Lym_X, Lym_Y, Lym_Z, MCHC, Micro were all independent risk factors for diagnosing radiation injury on radiation workers ( OR=1.08、1.02、0.99、1.06、51.32, P<0.05) . ROC curve analysis showed that the AUC, sensitivity, specificity, and accuracy of the logistic regression model based by Lym_X, Lym_Y, Lym_Z, MCHC and Micro in diagnosing radiation injury on radiation workers were 0.80, 85.9%, 65.8% and 75.9% respectively. The validation queue verified the logistic regression model and the AUC, sensitivity, specificity, and accuracy of the logistic regression model were 0.80, 81.7%, 71.7% and 76.7% respectively, the model fitted well. Conclusion:Radiation damage can cause changes in multiple whole blood cell parameters of radiation workers. The logistic regression model based by Lym_X, Lym_Y, Lym_Z, MCHC and Micro showed good diagnosis ability and can be used for the screening of radiation injury on radiation workers.

Objective:To evaluate the diagnostic value of gene testing in familial hypercholesterolemia (FH) in patients with premature myocardial infarction(PMI).Methods:This study was a single center cross-sectional study. A retrospective analysis was made on PMI patients who visited the People′s Hospital of Peking University from May 1, 2015 to March 31, 2017. Clinical data of patients was collected and gene testing of FH related genes low density lipoprotein receptor (LDLR), proprotein convertase subtilisin/kexin type 9 (PCSK9), apolipoprotein B(APOB) and low density lipoprotein receptor adaptor protein 1(LDLRAP1) was carried out. Clinical diagnosis of FH patients was performed using Simon Broome criteria, DLCN criteria, and FH Chinese expert consensus.Results:There were 188 males (83.6%) among 225 PMI patients, and the age of the first myocardial infarction was (46.6±7.2) years old. Ten patients carried FH pathogenic or possibly pathogenic mutations (4.4%). Compared with Simon Broome standard, DLCN standard and FH Chinese expert consensus, gene testing increased the diagnostic rate of FH by 53.3%, 33.3% and 42.1% respectively.Conclusion:Gene testing is helpful to improve the diagnosis of FH, and it is important to start the standard treatment of FH as early as possible in patients with premature myocardial infarction.

Vascular injury resulting from lower limb amputation leads to the redistribution of blood flow and changes in vascular terminal resistance, which can affect the cardiovascular system. However, there was no clear understanding of how different amputation levels affect the cardiovascular system in animal experiments. Therefore, this study established two animal models of above-knee amputation (AKA) and below-knee amputation (BKA) to explore the effects of different amputation levels on the cardiovascular system through blood and histopathological examinations. The results showed that amputation caused pathological changes in the cardiovascular system of animals, including endothelial injury, inflammation, and angiosclerosis. The degree of cardiovascular injury was higher in the AKA group than in the BKA group. This study sheds light on the internal mechanisms of amputation's impact on the cardiovascular system. Based on the amputation level of patients, the findings recommend more comprehensive and targeted monitoring after surgery and necessary interventions to prevent cardiovascular diseases.
Animals ; Animal Experimentation ; Cardiovascular System ; Cardiovascular Diseases ; Hypertension ; Amputation, Surgical

It has been found that the incidence of cardiovascular disease in patients with lower limb amputation is significantly higher than that in normal individuals, but the relationship between lower limb amputation and the episodes of cardiovascular disease has not been studied from the perspective of hemodynamics. In this paper, numerical simulation was used to study the effects of amputation on aortic hemodynamics by changing peripheral impedance and capacitance. The final results showed that after amputation, the aortic blood pressure increased, the time averaged wall shear stress of the infrarenal abdominal aorta decreased and the oscillatory shear index of the left and right sides was asymmetrically distributed, while the time averaged wall shear stress of the iliac artery decreased and the oscillatory shear index increased. The changes above were more significant with the increase of amputation level, which will result in a higher incidence of atherosclerosis and abdominal aortic aneurysm. These findings preliminarily revealed the influence of lower limb amputation on the occurrence of cardiovascular diseases, and provided theoretical guidance for the design of rehabilitation training and the optimization of cardiovascular diseases treatment.
Amputation ; Aorta, Abdominal/surgery* ; Aortic Aneurysm, Abdominal/surgery* ; Blood Flow Velocity/physiology* ; Hemodynamics/physiology* ; Humans ; Lower Extremity ; Models, Cardiovascular ; Stress, Mechanical

Lower limb amputation is a significant change in body structure. Loss of muscle, blood vessels, and blood leads to a redistribution of blood flow and changes in resistance at the end of blood vessels. In view of the significant increase in the prevalence of cardiovascular disease after lower limb amputation, the mechanism of which is still unclear, this study aims to establish an animal research model that can verify and explore the effects of amputation on cardiovascular system, and provide the experimental basis for subsequent animal experiments when exploring the effect of different amputation levels on the cardiovascular system. SPF New Zealand rabbits were divided into normal group ( n = 6) and amputation group ( n = 6). The amputation group was treated with above-knee amputation. The changes of low-density liptein cholesterol (LDL-C) and total cholesterol (TC) in serum of all the rabbits were monitored regularly after the surgery. The arterial pathological examination was conducted after the experimental rabbits were executed. The results showed that compared with the normal group, serum LDL-C content and TC content in the amputation group were significantly increased ( P<0.05); The blood vessels of the amputated rabbits had pathological changes such as degeneration and necrosis of smooth muscle cells in the middle membrane layer and rupture of elastic fibers. At the abdominal aorta and aortic arch, the elastic fiber area expression percentage (EFEP) of the experimental group was significantly lower than that of the normal group. The results suggest that the cardiovascular system of rabbits has the tendency of decreased arterial elasticity and lipid deposition in blood after amputation, indicating that the animal research model on the effect of amputation on the cardiovascular system has been successfully established, and can provide an experimental platform for further study on the mechanism of the effect of amputation on the cardiovascular system.
Rabbits ; Animals ; Cholesterol, LDL ; Disease Models, Animal ; Amputation, Surgical ; Myocytes, Smooth Muscle ; Arteries

Corona virus disease 2019 (COVID-19) has been the focus of global attention since its outbreak. With the rapid spreading of COVID-19, serious challenges including medical management system, medical resources, emergency response, medical devices and instruments gradually occur, revealing many shortcomings among these aspects. Herein, through the principles, viewpoints and methods of biomechanics, this article recognizes and analyzes the existing problems that are urgently needed to be solved, such as the study of in-vitro viability of the virus, the biomechanics of aerosol, the fluid mechanics in public transportation and places, the relationship between respiratory diseases and cardiovascular diseases, the improvement of medical devices, with an objective of taking advantages of biomechanics in epidemic prevention and control, so as to promote the development of biomechanics.

Objective To investigate the influence of exogenous p53mut, p53wt and p16 on the expression of Smad4 in lung cancer H1299 cells. Methods Target genes (p53mut, p53wtand p16) were amplified by PCR and inserted into effective eukaryotic expression vector pIRES2-EGFP, respectively. These recombinant plasmids were transfected into H1299 cells by lipofectamine. The fluorescence microscope was employed to observe the transfected cells and the expression of EGFP. RT-PCR was used to validate the transfection efficiency. Western blot assay was used to detect the change of the Smad4 expression in H1299, Results Green fluorescence was observed under fluorescence microscope in the transfected H1299 cells at 72 hour post transfection. RT-PCR indicated that p53mut, p53wt and p16 genes were highly expressed in H1299 cell. There was no significant difference in Samd4 expression between the empty plasmid group and control group(P＞0.05). But the expression of Samd4 in p53mut transfected group was decreased(P＜0.05). On the contrary, the expression of Smad4 was increased in the p53wt transfected group and P53wt and p16 co-transfected group. Moreover, the increase was more obvious in the P53wt and p16 cotransfected group(P＜ 0.05). Conclusion P53mut gene transfection reduces the expression of Smad4 and P53wt. The co-infection of p53mut and p16 increases the expression of Smad4 in the H1299 cells. The tumor promoting effect of p53mut and the antitumor effect of p53^ and p16 may be related to the signal pathway of TGF-β/Smad4.