1.Mechanism of Yizhi Qingxin Prescription in Regulating PKA/CaN Pathway to Improve Cognitive Function in Alzheimer's Disease Model Mice
Xiaochen GUO ; Jiangang LIU ; Dandan SHI ; Ziqi NING ; Yaoyao ZHANG ; Fang LIU ; Meixia LIU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(3):97-108
ObjectiveTo explore the mechanism by which Yizhi Qingxin prescription improves mitochondrial dysfunction in Alzheimer's disease (AD) through regulating mitochondrial Ca2+ homeostasis and kinetic balance based on the protein kinase A (PKA)/calcineurin (CaN) signaling pathway. MethodsSixty three-month-old amyloid precursor protein (APP)/presenilin 1 (PS1) double transgenic mice were randomly divided into a model group, a donepezil group(0.65 mg·kg-1), a low-dose Yizhi Qingxin prescription group (YQF-L,2.6 g·kg-1), a medium-dose Yizhi Qingxin prescription group (YQF-M,5.2 g·kg-1), and a high-dose Yizhi Qingxin prescription group (YQF-H,10.4 g·kg-1), with 12 mice in each group. Twelve C57BL/6J mice with the same genetic background served as a normal group. Each treatment group received gavage administration daily, with the model and normal groups receiving equal volume of physiological saline. Intervention continued for 12 consecutive weeks. The learning and memory abilities of the mice were assessed using the novel object recognition (NOR) and Morris water maze (MWM) tests. Hematoxylin-eosin (HE)/Nissl staining was used to observe histopathological changes in the hippocampus. Transmission electron microscopy (TEM) was used to observe mitochondrial ultrastructure. Fluo-4 acetoxymethyl ester (Fluo-4 AM) Ca2+ probe was used to measure intracellular Ca2+ concentration in brain tissue. Western blot was used to determine the protein expression of PKA, CaN, sodium/calcium/lithium exchanger (NCLX), mitochondrial calcium uniporter (MCU), calmodulin (CaM), dynamin-related protein 1 (Drp1), and phosphorylated dynamin-related protein 1 (serine 637 site) [p-Drp1(S637)] in the hippocampus. Real-time quantitative polymerase chain reaction (Real-time PCR) was used to measure the expression of PKA, CaN, CaM, NCLX, MCU, and Drp1 mRNAs. ResultsCompared with those in the normal group, the recognition index (RI) of the model group decreased (P0.01), and the number of crossings through the original platform area, the duration of stay in the target quadrant, and the distance were reduced (P0.01). The protein expression of PKA, NCLX, and p-DRP1 (ser637) significantly decreased (P0.05), and the mRNA expression of PKA and NCLX significantly decreased (P0.05). The escape latency (EL) was prolonged (P0.05), and the intracellular Ca2+ level significantly increased (P0.01). The protein expression of CaN, CaM, MCU, and Drp1, as well as the mRNA expression of CaN, MCU, and Drp1, significantly increased (P0.05). After intervention with Donepezil and Yizhi Qingxin prescription, compared with that in the model group, the RI of the treatment group significantly increased (P0.05), and the number of crossings through the platform and the duration of stay in the target quadrant significantly increased (P0.05). The protein expression of PKA, NCLX, and p-Drp1 (ser637) and the mRNA expression of PKA and NCLX significantly increased (P0.05). On the 4th and 5th days, the EL was shortened (P0.05), and the intracellular Ca2+ level decreased (P0.05). The protein expression of CaN, CaM, MCU, and Drp1 and the mRNA expression of CaN, MCU, and Drp1 significantly decreased (P0.05). ConclusionYizhi Qingxin prescription regulates the PKA/CaN pathway, upregulates the expression of PKA, NCLX, and p-Drp1 (ser637) proteins, reduces the expression of CaN, CaM, MCU, and Drp1 proteins, and regulates Ca2+ homeostasis and mitochondrial dynamic balance, thereby enhancing the spatial learning and memory abilities of AD mice.
2.Mechanism of Yizhi Qingxin Prescription in Regulating PKA/CaN Pathway to Improve Cognitive Function in Alzheimer's Disease Model Mice
Xiaochen GUO ; Jiangang LIU ; Dandan SHI ; Ziqi NING ; Yaoyao ZHANG ; Fang LIU ; Meixia LIU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(3):97-108
ObjectiveTo explore the mechanism by which Yizhi Qingxin prescription improves mitochondrial dysfunction in Alzheimer's disease (AD) through regulating mitochondrial Ca2+ homeostasis and kinetic balance based on the protein kinase A (PKA)/calcineurin (CaN) signaling pathway. MethodsSixty three-month-old amyloid precursor protein (APP)/presenilin 1 (PS1) double transgenic mice were randomly divided into a model group, a donepezil group(0.65 mg·kg-1), a low-dose Yizhi Qingxin prescription group (YQF-L,2.6 g·kg-1), a medium-dose Yizhi Qingxin prescription group (YQF-M,5.2 g·kg-1), and a high-dose Yizhi Qingxin prescription group (YQF-H,10.4 g·kg-1), with 12 mice in each group. Twelve C57BL/6J mice with the same genetic background served as a normal group. Each treatment group received gavage administration daily, with the model and normal groups receiving equal volume of physiological saline. Intervention continued for 12 consecutive weeks. The learning and memory abilities of the mice were assessed using the novel object recognition (NOR) and Morris water maze (MWM) tests. Hematoxylin-eosin (HE)/Nissl staining was used to observe histopathological changes in the hippocampus. Transmission electron microscopy (TEM) was used to observe mitochondrial ultrastructure. Fluo-4 acetoxymethyl ester (Fluo-4 AM) Ca2+ probe was used to measure intracellular Ca2+ concentration in brain tissue. Western blot was used to determine the protein expression of PKA, CaN, sodium/calcium/lithium exchanger (NCLX), mitochondrial calcium uniporter (MCU), calmodulin (CaM), dynamin-related protein 1 (Drp1), and phosphorylated dynamin-related protein 1 (serine 637 site) [p-Drp1(S637)] in the hippocampus. Real-time quantitative polymerase chain reaction (Real-time PCR) was used to measure the expression of PKA, CaN, CaM, NCLX, MCU, and Drp1 mRNAs. ResultsCompared with those in the normal group, the recognition index (RI) of the model group decreased (P0.01), and the number of crossings through the original platform area, the duration of stay in the target quadrant, and the distance were reduced (P0.01). The protein expression of PKA, NCLX, and p-DRP1 (ser637) significantly decreased (P0.05), and the mRNA expression of PKA and NCLX significantly decreased (P0.05). The escape latency (EL) was prolonged (P0.05), and the intracellular Ca2+ level significantly increased (P0.01). The protein expression of CaN, CaM, MCU, and Drp1, as well as the mRNA expression of CaN, MCU, and Drp1, significantly increased (P0.05). After intervention with Donepezil and Yizhi Qingxin prescription, compared with that in the model group, the RI of the treatment group significantly increased (P0.05), and the number of crossings through the platform and the duration of stay in the target quadrant significantly increased (P0.05). The protein expression of PKA, NCLX, and p-Drp1 (ser637) and the mRNA expression of PKA and NCLX significantly increased (P0.05). On the 4th and 5th days, the EL was shortened (P0.05), and the intracellular Ca2+ level decreased (P0.05). The protein expression of CaN, CaM, MCU, and Drp1 and the mRNA expression of CaN, MCU, and Drp1 significantly decreased (P0.05). ConclusionYizhi Qingxin prescription regulates the PKA/CaN pathway, upregulates the expression of PKA, NCLX, and p-Drp1 (ser637) proteins, reduces the expression of CaN, CaM, MCU, and Drp1 proteins, and regulates Ca2+ homeostasis and mitochondrial dynamic balance, thereby enhancing the spatial learning and memory abilities of AD mice.
3.Influencing factors of work-related musculoskeletal disorders among medical staff: a Bayesian network modeling analysis
Li HU ; Feiruo ZHANG ; Yongmei ZHAO ; Ning FANG ; Guixin YU ; Dan LIU ; Dongdong CAO ; Leihan XU ; Zihuan WANG ; Mingxiao GUO ; Yan YE
China Occupational Medicine 2025;52(6):631-636
Objective To understand the current situation and influencing factors of work-related musculoskeletal disorders (WMSDs) in medical staff in Beijing City. Methods A total of 2 687 medical staff were selected as the research subjects using the multi-stage sampling method. The current situation of WMSDs and occupational stress, anxiety symptoms, depressive symptoms, and insomnia symptoms were investigated using the Musculoskeletal Disorders Questionnaire, the Core Occupational Stress Scale, the Generalized Anxiety Disorder Scale, the Patient Health Questionnaire Depression Scale, and the Self-Sleep Management Questionnaire. The Max-Min Hill-Climbing algorithm was used to construct a Bayesian network model to analyze the influencing factors and internal relationships of WMSDs and to conduct reasoning and prediction of the model. Results The prevalence of WMSDs among the research subjects was 88.9%. Binary logistic regression analysis was used to identify age, educational level, personal monthly income, anxiety symptoms, depressive symptoms, insomnia symptoms, prolonged forward-head desk work, and prolonged static posture work to construct the Bayesian network model. The model consisted of nine nodes and eleven directed edges. Prolonged static posture work, prolonged forward-head desk work, and anxiety symptoms were directly related to WMSDs. Age and educational level were indirectly related to WMSDs through their influence on prolonged forward-head desk work. Depression symptoms were indirectly associated with WMSDs through their influence on anxiety symptoms. The model's prediction accuracy was 90.5%. Conclusion The prevalence of WMSDs among medical staff in Beijing City is relatively high. Prolonged static posture work, prolonged forward-head desk work, and anxiety symptoms may directly increase the risk of developing WMSDs.
4.Biparametric MRI-based peritumoral radiomics for preoperative prediction of extracapsular extension in prostate cancer
Honghao XU ; Qicong DU ; Yuanhao MA ; Xueyi NING ; Baichuan LIU ; Xu BAI ; Di CHEN ; Yun ZHANG ; Zhe DONG ; Chuang JIA ; Xiaojing ZHANG ; Xiaohui DING ; Baojun WANG ; Aitao GUO ; Jian XUE ; Xuetao MU ; Huiyi YE ; Haiyi WANG
Chinese Journal of Radiology 2025;59(9):1055-1062
Objective:To investigate the value of biparametric-MRI (bpMRI) based peritumoral radiomics for preoperative prediction of extraprostatic extension (EPE) in prostate cancer (PCa).Methods:In this cross-sectional study, consecutive bpMRI of patients undergoing prostatectomy for PCa were retrospectively collected from the First Medical Center (center 1) and the Third Medical Center (center 2) of Chinese PLA General Hospital. A total of 274 patients were finally enrolled. Patients at center 1 from January 2020 to December 2022 were randomly divided into a training set (149 cases) and an internal validation set (63 cases) by stratified random sampling. Patients at center 2 from January 2023 to March 2024 were assigned to the external test set (62 cases). Patients were categorized into EPE-positive group and EPE-negative group according to pathological assessment postoperatively. In the training set, there were 49 cases in EPE-positive group and 100 cases in EPE-negative group. In the internal validation set, there were 26 cases in EPE-positive group and 37 cases in EPE-negative group. In the external test set, there were 22 cases in EPE-positive group and 40 cases in EPE-negative group. Axial T 2WI and apparent diffusion coefficient (ADC) images were manually annotated to obtain index lesion regions of interest (ROIs), with the peritumoral ROIs subsequently delineated by semi-automatic segmentation technique. Radiomics features were extracted from intra-tumoral, peri-tumoral, and intra-tumoral plus peri-tumoral ROIs. The training set data was employed to select and optimize features to build the radiomics models. The logistic regression analysis was used to develop radiomics, clinical, and integrated models. The predictive performance was assessed by the area under the receiver operating characteristic curve (AUC) in the external test set, and compared by the DeLong test. The sensitivity and specificity were compared by the exact McNemar test. Results:In the external test set, the peri-tumoral radiomics model based on bpMRI showed the highest performance in evaluating EPE, with an AUC of 0.739 (95% CI 0.611-0.842), which was identified as the optimal radiomics model. EPE grade ( OR=6.151, 95% CI 3.371-11.226, P<0.001) was incorporated into the clinical model, with an AUC of 0.780 (95% CI 0.657-0.875) in the external test set. The integrated model had an AUC of 0.817 (95% CI 0.698-0.904) in the external test set. There was no statistically significant difference in comparisons of AUCs among the three models (all P>0.05). The sensitivity of the integrated model (68.2%) showed no significant difference from those of the clinical model and the optimal radiomics model (77.3% and 86.4%, respectively; P=0.500 and P=0.289). However, the specificity of the integrated model (85.0%) was significantly higher than those of the clinical model (67.5%, P=0.016) and the optimal radiomics model (50.0%, P<0.001). Conclusion:A bpMRI-based peritumoral radiomics integrating clinical model demonstrates high performance for preoperative prediction of EPE in PCa.
5.Epidemiological Characteristics of Female Breast Cancer in Henan Province in 2020 and Its Temporal Trends from 2010 to 2020
Shucun MAO ; Qiong CHEN ; Shuzheng LIU ; Hongwei LIU ; Yin LIU ; Huifang XU ; Xiaoli GUO ; Hong WANG ; Xiaoyang WANG ; Chenxi FENG ; Ning ZHANG ; Shaokai ZHANG
China Cancer 2025;34(7):507-512
[Purpose]To analyze the incidence and mortality rates of female breast cancer in Henan Province in 2020 and the trends from 2010 to 2020.[Methods]Breast cancer incidence and mor-tality data stratified by urban and rural areas and age groups were collected from Henan Provincial tumor registry,and the province's household population statistics were used.The crude incidence/mortality rate,age-standardized incidence/mortality rate by Chinese standard population(ASIRC/ASMRC)and world standard population(ASIRW/ASMRW),cumulative rate(0~74 year old)were calculated.The annual percentage change(APC),average annual percentage change(AAPC)and 95%confidence interval(CI)were calculated using Joinpoint software to analyze the trends of the incidence and mortality from 2010 to 2020.[Results]In 2020,24 744 new cases and 4 989 deaths of female breast cancer were documented in Henan Province,with a crude incidence rate of 46.96/105,ASIRC of 38.43/105 and ASIRW of 35.71/105;a crude mortality rate of 9.47/105,ASMRC of 6.80/105 and ASMRW of 6.72/105,respectively.The above indicators in urban areas were signifi-cantly higher than those in rural areas.The highest incidence was observed in the age group of 50~54 years old,while the highest mortality reached in the age group of 85 years old and above.From 2010 to 2020,the overall incidence of female breast cancer showed a slow upward trend(AAPC=2.09%,95%CI:0.62%~3.58%,P=0.010),while the mortality rate exhibited a signif-icant downward trend(AAPC=-3.49%,95%CI:-5.62%~-1.30%,P=0.005).[Conclusion]The incidence and mortality rates of female breast cancer in Henan Province are still at a high level,and corresponding preventive measures and control strategies are needed to effectively reduce the health hazards of breast cancer to women.
6.Effect of high-fat on NOX4-SIRT1 signaling pathway in vascular aging
Dandan SHI ; Meixia LIU ; Jiangang LIU ; Xiaochen GUO ; Ziqi NING ; Yaoyao ZHANG
Chinese Journal of Geriatric Heart Brain and Vessel Diseases 2025;27(7):871-876
Objective To observe the alterations of protein expression of nicotinamide adenine di-nucleotide phosphatase oxidase 4-silent mating type information regulation 2 homolog 1(NOX4-SIRT1)signaling pathway in ApoE-/-mice and C57BL/6J mice induced by high-fat diet.Methods Twenty ApoE-/-mice and 40 C57BL/6J mice,aged of 10 weeks and half male and half female,were randomly divided into a NC group and a HFD group,with 10 mice in each group(ApoE-/-+NC and ApoE-/-+HFD groups,and C57+NC and C57+HFD groups).After 1 week of adaptive feed-ing period,each group was fed with their corresponding diet for subsequent 12 weeks,and then blood samples were collected from the anesthetized orbits and aortic arch tissues were harvested.HE staining and Masson staining were performed to examine the pathological morphology of the aortic arch tissues.The serum levels of TG,TC,HDL-C and LDL-C were measured using an auto-matic biochemical analyzer.The content of ox-LDLC was detected with ELISA,and the contents of ROS,GSH,GPX and NAD+were measured by colorimetry.The expression of SIRT1,p53,p21 and NOX4 was detected by Western blotting.Results Compared with the C57+NC group,the ApoE-/-+NC group showed significant lipid deposition,increased collagen fibers,elevated levels of TC,TG,HDLC,LDL-C,ox-LDL-C and ROS and increased p21 expression level,and obviously decreased contents of GSH,GPX and NAD+(P<0.05,P<0.01).Compared with the ApoE-/-+NC group,the ApoE-/-+HFD group showed larger plaque areas,lessened elastic fibers,more col-lagen fibers,increased levels of TC,HDL-C,LDL-C,ox-LDL-C and ROS,and p21 expression level(P<0.01),and declined expression of GSH,GPX,NAD+and NOX4[6.4±0.8 μmol/L vs 9.6±0.8 μmol/L,242.0±39.0 U/ml vs 362.7±11.1 U/ml,0.61±0.15 nmol/L vs 1.07±0.20 nmol/L,0.26±0.01 vs 0.32±0.03;P<0.05,P<0.01[.Conclusion High-fat diet may accelerate vascular aging by elevating lipid and oxidative stress levels,decreasing NAD+and NOX4 expression,ele-vating p21 expression,and thereby activating the NOX4-SIRT1 pathway.
7.Clinical study of intracranial hypotension targeted body posture combined with pharmacotherapy in the treatment of chronic subdural hematoma
Jiayu CHEN ; Zhe WANG ; Di ZANG ; Ruizhe ZHENG ; Xiangru YE ; Zengxin QI ; Zeyu XU ; Zhiqiang LI ; Chengfeng SUN ; Liangjun SHEN ; Luoping SHENG ; Fulin XU ; Ruyong YE ; Kaiyu ZHOU ; Weijun TANG ; Yueqing HU ; Dapeng SHI ; Yuquan WANG ; Xizhen WU ; Ying WANG ; Qilin ZHANG ; Feili LIU ; Guo YU ; Yiping LU ; Yirui SUN ; Ning ZHANG ; Feng HUANG ; Xialong GU ; Han ZHANG ; Jian DING ; Yongyan BI ; Haolan DU ; Jing ZHANG ; Hailong JI ; Ding DING ; Wei ZHANG ; Xuehai WU
Chinese Journal of Surgery 2025;63(3):212-218
Objective:To compare the efficacy of body posture combined with pharmacotherapy and pharmacotherapy alone in the treatment of chronic subdural hematoma(CSDH).Methods:Firstly, retrospective case series study was conducted. Thirty cases of CSDH that had received body posture combined with pharmacotherapy at Department of Neurosurgery, Huashan Hospital Affiliated to Fudan University from December 2016 to October 2020 were studied retrospectively. Twenty-seven patients were male, and 3 patients were female. The age of patients ( M(IQR)) was 66(16) years (range:28 to 84). Nineteen patients had unilateral hematoma, and 11 patients had bilateral hematoma. All patients received pharmacotherapy and body posture therapy that was to raise their lower limbs 20 to 30 cm with leg lift pad and get abdominal compressed with customized abdominal belt in supine position. Patients were required to maintain the body posture as much as possible, with the maximum to 16 to 18 hours per day. Patients with unilateral hematoma should tilt the head to the affected side and avoid tilting it to the opposite side. For patients with bilateral hematoma, there was no need for head lateralization. Patient were treated with oral dexamethasone and atorvastatin simultaneously. The preliminary efficacy of body posture combined with pharmacotherapy was determined by hematoma improvement rate which was analyzed by Clopper-Pearson method. Then, the multi-center, prospective, randomized controlled trial had carried out in 9 medical centers from August 2020 to November 2021. The stratified block randomization method was adopted. Patients were randomized in a ratio of 1∶1 to either receive pharmacotherapy alone(the control group) or body posture combined with pharmacotherapy(the experiment group) for 3 months and followed up for 6 months. Effective treatment was defined as complete absorption of hematoma, or the hematoma volume decreased by more than 10 ml and Markwalder grading scale score had improved by more than 1 point compared to the baseline. The efficacy rate and surgery conversion rate at 3 months and recurrence at 6 months were observed. Comparison between groups was performed with paired sample t test, Mann-Whitney U test, χ2 test, corrected χ2 test, or Fisher exact probability method. Logistic regression was used to compare the effective rate and operation rate between the two groups. Results:In the respective study, 30 patients completed follow-up 13 to 353 days after treatment. At the last follow-up, the incidence of almost complete absorption or significantly absorption of hematoma (hematoma volume was significantly reduced accompanied by symptom improvement) was 93.3%. The 95% CI for the incidence that analyzed by the Clopper-Pearson method was 77.9% to 99.2%. One hundred and six patients were enrolled in the multicenter study. Fifty-five patients underwent body posture combined with pharmacotherapy. The age was 74(17) years (range:26 to 92). Thirty-nine patients were males and 16 were females. Fifty-one patients underwent pharmacotherapy alone. The age was 69(12) years (range:48 to 84). Thirty-seven patients were males and 14 were females. The length of body posture recorded in diary card was (15.7±2.3) hours(range:7.6 to 19.3 hours). The efficacy rate in the body posture combined with pharmacotherapy group and pharmacotherapy alone group were 83.6% (46/55) and 56.9% (29/51), respectively at 3 months. The result of the logistic regression analysis showed that the efficacy of body posture combined with pharmacotherapy group was better than that of pharmacotherapy alone group ( OR=3.88,95% CI:1.57 to 9.58, P=0.003). Surgery rate in the body posture combined with pharmacotherapy group and pharmacotherapy alone group were 5.5% (3/55) and 21.6% (11/51) respectively. The result of Logistic regression showed that the pharmacotherapy alone group was more likely to be converted to surgery ( OR=0.21,95% CI:0.05 to 0.80, P=0.023). At the 6 months, no recurrence of cases was found in the body posture combined with pharmacotherapy group. However, the recurrence rate of pharmacotherapy alone group was 6.3% (3/48), there was no significant difference between the two groups ( P>0.05). Conclusion:The effect of body posture combined with pharmacotherapy for chronic subdural hematoma is better than that of pharmacotherapy alone.
8.Structural equation analysis and modeling of fect and ankles WMSDs and its adverse ergonomic factors
Xi ZHANG ; Ning JIA ; Xin SUN ; Meibian ZHANG ; Qing XU ; Huadong ZHANG ; Ruijie LING ; Yimin LIU ; Gang LI ; Yan YIN ; Hua SHAO ; Hengdong ZHANG ; Yanmin QI ; Bing QIU ; Tiebing LIU ; Dayu WANG ; Qiang ZENG ; Yan YE ; Bin XIAO ; Hua ZOU ; Jianchao CHEN ; Dongxia LI ; Yongquan LIU ; Jixiang LIU ; Enfei JIANG ; Jun QI ; Liangying MEI ; Tianlai LI ; Mimi YANG ; Xinwei GUO ; Zhongxu WANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2025;43(2):101-109
Objective:To explore the structural equation model to explore the levels of work-related musculoskeletal disorders (WMSDs) and various risk factors in the feet and ankle of China's occupational population, providing scientific basis for for preventing WMSDs in feet and ankles.Methods:Data of 73497 national occupational epidemiological cases were selected from June 2018 to December 2023 used the Chinese version of the Electronic Questionnaire on Musculoskeletal Disorders. The adverse ergonomic factors and their source classification standard and confirmatory factor analysis were used to investigate foot and ankle WMSDs and their related risk factors (including individual factors, work organization, work posture, work type, fatigue, etc.) in key occupational groups in China, and structural equation model hypothesis, fitting, verification, and path and intermediary effect analysis were carried out. The model fit evaluation indexes included Chi-square specific degrees of freedom ( χ2/ df), gauge fit index (NFI), Tucker Lewis index (TLI), goodness of Fit index (GFI), adjusted Goodness of Fit index (AGFI) and approximate root mean square error (RMSEA) . Results:A total of 73497 occupational workers were surveyed, with local muscle fatigue and WMSDs incidence rates in the feet and ankles being 17.17% and 12.06%, respectively. The fitting index of the adjusted structural equation model basically meets the standard (GFI=1, AGFI=1, RMESA=0.042, NFI=0.716, TLI=0.663). The top three factors affecting feet and ankle WMSDs are feet and ankle muscle fatigue, work type, and work organization, with standardized path coefficients of 0.221, 0.105, and 0.095, respectively. The top two factors affecting feet and ankle muscle fatigue are work organization and work type, with standardized path coefficients of 0.548 and 0.383, respectively. Feet and ankle muscle fatigue, work type, work organization, and work posture have a direct effect on feet and ankle WMSDs, with effect values of 0.221, 0.105, 0.095, and 0.077, respectively. The organization and type of work can also have indirect effects through feet and ankle muscle fatigue, with effect values of 0.121 and 0.084, respectively.Conclusion:Feet and ankle muscle fatigue has a direct impact on WMSDs, and plays a mediating role between ankle and ankle WMSDs caused by work organization and work type. Feet and ankle muscle fatigue is an important pathway leading to feet and ankle WMSDs. It is recommended that employers and managers detect job fatigue early and take corresponding prevention and intervention measures, which can play a key role in preventing feet and ankle WMSDs.
9.Structural equation analysis and modeling of upper limb WMSDs and their adverse ergonomic factors
Siwu ZHONG ; Ning JIA ; Xin SUN ; Meibian ZHANG ; Qing XU ; Huadong ZHANG ; Ruijie LING ; Yimin LIU ; Gang LI ; Yan YIN ; Hua SHAO ; Jue LI ; Hengdong ZHANG ; Bing QIU ; Dayu WANG ; Qiang ZENG ; Rugang WANG ; Yan YE ; Bin XIAO ; Hua ZOU ; Jianchao CHEN ; Dongxia LI ; Yongquan LIU ; Qinghua SHI ; Jixiang LIU ; Enfei JIANG ; Jun QI ; Liangying MEI ; Xianfeng ZHAO ; Mimi YANG ; Xinwei GUO ; Zhi WANG ; Zhongxu WANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2025;43(4):254-263
Objective:To explore the structural relationship between WMSDs in the upper limbs and various risk factors in the occupational population in China, based on a large sample epidemiological survey and structural equation analysis, and to establish a structural equation model, so as to lay a foundation for the prevention and control of such diseases.Methods:The Chinese version of the Musculoskeletal Disorders Electronic Questionnaire was used to conduct a nationwide survey on the prevalence of WMSDs in the upper extremity. Six factors related to WMSDs in the upper extremity were extracted by the classification standard of adverse ergonomic factors and their source and confirmatory factor analysis, including work organization, work type, upper extremity work posture, individual factors, upper extremity fatigue and upper extremity WMSDs. The structural equation analysis was carried out and the structural equation model was established.Results:The incidence of WMSDs and fatigue in the upper limbs was 24.44% and 43.76%, respectively. The adjusted structural equation model fitting indicators were generally up to the standard (GFI=1.000, AGFI=1.000, RMSEA=0.043, NFI=0.808, TLI=0.784) . The four exogenous latent variables of work organization, work type, upper limb work posture and individual factors were correlated. There was a strong positive correlation between job type and upper limb work posture ( r=0.865) , a moderate positive correlation between work organization and job type and upper limb work posture ( r=0.570, 0.490) , and a weak negative correlation between individual factors and the other three exogenous latent variables. Upper limb work posture and individual factors had direct effects on upper limb WMSDs, and the effect coefficients were 0.10 and 0.06, respectively. Upper limb fatigue played a mediating role between work organization, work type, upper limb work posture and upper limb WMSDs. The effect coefficient was 0.46, and the composition ratios of indirect effects were 100.0%, 100.0%, and 38.3%, respectively. The direct path effect of upper limb work posture, individual factors and upper limb WMSDs was weaker than the mediating path through upper limb fatigue. Conclusion:When carrying out the prevention and control of upper limbWMSDs, it is necessary to comprehensively consider the pathogenesis path of upper limb muscle fatigue and upper limb WMSDs caused by work organization, work type, and upper limb work posture, so as to provide theoretical reference for improving the prevention and control level of such diseases.
10.The Influence of Boundary Condition Changes of Inner and Outer Walls of Osteon on Fluid Flow Characteristics:A Finite Element Study
Weilun YU ; Xiuying LIU ; Qiong WANG ; Yuan YAO ; Yubo GUO ; Ning QU ; Xiaogang WU ; Haoyu FENG ; Zhiqiang LI
Journal of Medical Biomechanics 2025;40(3):656-662
Objective To explore the characteristics of fluid flow within loaded osteons under different boundary conditions.Methods The COMSOL Multiphysics software was used to establish a three-dimensional(3D)finite element model of osteons with different boundary conditions,and the variation rules of pore pressure and flow velocity of osteons under different inner wall pulsating blood pressures and outer wall elastic constraint conditions were analyzed.Results As the pulsatile blood pressure inside the osteon increased from 0 mmHg(1 mmHg=0.133 kPa)to 300 mmHg,the peak pore pressure within the osteon correspondingly increased from 26 kPa to 68 kPa.As the elastic constraint on the outer wall of osteons changed from being completely elastic to completely constrained,the peak pore pressure within osteons increased from 15 kPa to 26 kPa,and the peak flow velocity increased from 0.04 um/s to 0.07 um/s.Conclusions This study reveals the influence laws of changes in boundary conditions such as the pulsatile blood pressure on the inner wall and the elastic constraint on the outer wall of osteons on fluid flow characteristics within loaded osteons.These findings are conducive to a deeper understanding of the mechanical response mechanisms of bone tissues in both physiological and pathological states,and provide an important theoretical basrs for further researches on bone mechanotransduction.

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