BACKGROUND:There are studies on three-dimensional finite element analysis of total knee replacement, but few research concerns contact pressure and contact area inside and outside polyethylene liner of fixed prosthesis and rotating platform prosthesis in total knee replacement. OBJECTIVE:To explore the contact pressure and contact area inside and outside polyethylene liner of fixed platform prosthesis and rotating platform prosthesis in total knee replacement. METHODS:We established three-dimensional finite element models of fixed platform prosthesis and rotating platform prosthesis in total knee replacement and compared contact pressure and contact area inside and outside polyethylene liner of fixed platform prosthesis and rotating platform prosthesis in total knee replacement. RESULTS AND CONCLUSION:The peak contact pressure inside and outside polyethylene liner of fixed platform prosthesis and rotating platform prosthesis in total knee replacement was minimum at 0° of genuflex. The peak contact pressure inside polyethylene liner was higher than that outside polyethylene liner of fixed platform prosthesis and rotating platform prosthesis in total knee replacement at 0°-90° of genuflex (P<0.05). The peak contact pressure inside and outside polyethylene liner of fixed platform prosthesis was higher than that of rotating platform prosthesis in total knee replacement at 60°-120° of genuflex (P<0.05). The contact area inside and outside polyethylene liner of fixed platform prosthesis and rotating platform prosthesis in total knee replacement was maximum at 0° of genuflex. The contact area inside polyethylene liner of fixed platform prosthesis in total knee replacement was lower than that of outside at 0°-30° of genuflex (P<0.05). The contact area inside polyethylene liner of fixed platform prosthesis in total knee replacement was lower than that of outside at 0°-90° of genuflex (P<0.05). The contact area inside and outside polyethylene liner of fixed platform prosthesis was lower than that of rotating platform prosthesis in total knee replacement at 30°-120° of genuflex (P<0.05). These results suggested that peak contact pressure inside polyethylene liner of fixed and rotating platform prostheses was higher than that outside in total knee replacement, and the inside contact area was lower than that of outside. Inside and outside contact pressure of the rotating platform prosthesis was lower than that of fixed platform prosthesis. Inside and outside contact area of the rotating platform prosthesis was higher than that of fixed platform prosthesis.

EpigeneticsreferstoheritablealterationsingeneexpressionthatdonotinvolvetheDNA coding sequence itself.Epigenetic regulation plays an important role in gene expression,DNA replication,rep-aration and reconstitution. Thus, the abnormity of epigenetic regulation may lead to different diseases, especially cancer.SNF5 ,which can suppress tumor significantly,is one of the core components of SWI/SNF chromosome remodeling complexes.EZH2,a histone methyltransferase,is closely and complicatedly related to cancer and has significant effect on tumorigenesis.There are many studies reporting the effects of epigenetic regulation factors-SNF5 and EZH2 on different tumors as well as the interrelation at present.In the present paper,the advances in the research on these two epigenetic regulation factors in the carcinogenesis are reviewed.

Objective To investigate the relationship between serum albumin, bilirubin and cognitive impairment in patients with mild cognitive impairment (MCI). Methods Serum albumin, total bilirubin, direct bilirubin, indirect bilirubin were analyzed in 89 cases of MCI and 82 cases of cognitively normal control. All of the cases underwent neuropsychological testing by Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). The risk factors of MCI were subject to Logistic regression analysis. Results The serum level of total bilirubin in MCI group were significantly lower than that in controls (P < 0.05). There was no significant difference in albumin between MCI and control group (P > 0.05). The bilirubin level was positively correlated with MMSE scores and MoCA scores (including attention, delayed recall and abstract) (P < 0.05), while no significant correlation between serum albumin level and scores of MMSE and MoCA (P > 0.05) by using Spearman correlation analysis. Logistic regression analysis showed that age, education level, diabetes and serum bilirubin levels were independent risk factors for MCI. Conclusion Our data show that decreased serum level of bilirubin is positively related to cognitive impairment.

Objective To investigate Aβ42 and P-tau levels in cerebrospinal fluid (CSF) of patients with mild cognitive impairment (MCI). Methods CSF of 25 cases of MCI and 14 cases of cognitively normal (CN) were investigated. The CSF levels of Aβ42 and P-tau were detected by ELISA method. Correlation analysis was used to analyze the correlation between P-tau level and MMSE score in MCI. Results The CSF level of Aβ 42 was higher and P-tau was lower in MCI than CN group(P<0.05). P-tau level in MCI was also negatively correlated with MMSE score (P<0.05). Conclusion Aβ42 and P-tau levels in CSF may be valuable biological markers in the diagnosis of MCI. P-tau level in CSF of MCI may be related to the severity of cognitive impairment.

BACKGROUND:Three dimensional finite element analysis is widely used in orthopedics, but research in the knee flexion movement is not much. OBJECTIVE:To analyze biomechanical properties of knee flexion using finite element analysis.METHODS:Three dimensional finite element models and models of knee flexion at 30 degrees, 60 degrees and 120 degrees were established. Femoral forward movement, femur inward movement, tibia internal rotation and tibia vara were analyzed at different flexion angles. RESULTS AND CONCLUSION:(1) When knee flexion was at 30 degrees, 60 degrees and 120 degrees, the femur had backward movement. The backward movement value was larger at 60 degrees than at 30 and 120 degrees (P<0.05). The backward movement value was larger at 120 degrees than at 30 degrees (P>0.05). (2) The femur had outward movement at 30 degrees, and inward movement at 120 degrees. The inward movement value was significantly larger at 120 degrees than at 30 and 60 degrees (P<0.05). No significant difference in outward movement was determined between the 30 and 60 degrees (P>0.05). (3) Tibia internal rotation was not significantly different at 30, 60 and 120 degrees of flexion (P>0.05). (4) Tibia vara was found at 30, 60 and 120 degrees of flexion, but the tibia vara was not obvious at 120 degrees. The tibia vara was maximum at 60 degrees, and significantly higher than that at 120 degrees (P<0.05). The tibia vara was larger at 30 degrees than at 120 degrees (P>0.05). (5) These findings verify that backward movement was most obvious at 60 degrees. Femur inward movement was most large at 120 degrees. Tibia internal rotation was noticeable at 30 and 120 degrees. Tibia vara was remarkable at 60 degrees.

Patients with primary membranous nephropathy(PMN)tend to develop thrombosis,especially in the early phase of the disease.The pathogenesis of thrombosis is multifactorial,with hypoalbuminemia being widely regarded as an inde-pendent risk factor.Other factors include proteinuria,M-type phospholipase A2 receptor antibody,and D-dimer.Although prophy-lactic anticoagulation therapy is frequently used in clinical practice to prevent thrombosis in PMN patients,there are still many un-resolved issues regarding the optimal prevention of thrombosis in this condition.The timing of prophylactic anticoagulation,the threshold of serum albumin level,and the choice of treatment regimen are still lacking consensus.This article reviewed the relevant literature on these topics,aiming to establish a standard for thrombosis prevention and treatment for this population in the future and provide guidance for clinical practice.

Objective: To analyze factors impacting mental health status of medical students based on ecological systems theory, so as to provide reference for the mental health promotion system for medical students. Methods: In June 2024, 1 760 medical school students randomly selected from 19 different kinds of medical colleges in eastern China by stratified cluster were surveyed using questionnaires and expert interviews. Descriptive statistics, cross analysis, hierarchical linear regression analysis, structural equation models were used for data analysis. Results: Medical school students had higher satisfaction with the school (65.85%) and a great sense of perceived social support (57.16%). Furthermore, 91.14% of the students had normal interpersonal relationships. However, 44.89% reported that their mental health was impacted by high level of depression. The hierarchical linear regression analysis showed that the mental health outcomes of the medical students were positively predicted by higher perceived social support scores ( β =-11.40), institutional satisfaction ( β =-4.85 ), and lower help seeking stigma scores ( β =9.31) ( P <0.05). The structural equation modeling showed that the status of both perceived social support and self help seeking stigma had significant impacts on depression severity ( β =-0.32, -0.53) and interpersonal relationship sensitivity ( β =-0.31, 0.58) among medical students ( P <0.01).Through expert interviews, collaborations between the school and the tripartite organization (families, universities and society) was of growing importance. Conclusions Perceived social support and self stigma have a significant impact on the mental health status of medical students. The problem of self stigma of medical students should be paid attention to. Therefore, families, universities and society should work together to improve the mental health of medical students.

Objective To deeply analyze the problems of public hospitals in medical service satisfaction,construct a more applicable and explanatory service satisfaction evaluation model,and provide reference for the improvement path of patients'medical service satisfaction.Methods Based on the ESCI model,this paper puts forward a research hypothesis,compiles the"Medical Service Satisfaction Evaluation Scale of Public Hospitals in S City",selects S public hospitals as the research object,and evaluates medical service satisfaction from the perspective of patients.Results At present,the main problems affecting the improvement of patients'satisfaction with medical service management in public hospitals in S city are as follows:it is urgent to improve the diagnosis and treatment technology in terms of hardware quality and optimize the environmental hygiene of public hos-pitals,and it is an urgent task to shorten the waiting time for medical treatment in software quality.The score of medical service satisfaction evaluation of S public hospitals was 3.76,and the satisfaction of patients in S public hospitals with their medical serv-ices was at a moderately low level.Conclusion In view of the above problems,it is recommended to strengthen the construction of key specialties,strengthen the construction of talent team,optimize the medical process,open digital linkage services,and strengthen service management,so as to promote the improvement of patients'satisfaction with medical services.

ObjectiveTo investigate a foodborne disease outbreak and identify the pathogenic factors in order to prevent the occurrence of similar incidents. MethodsEpidemiological study， on-site food hygiene investigation， and laboratory testing were used to analyze the cause of outbreak in Company A. ResultsA total of 24 confirmed cases were screened out. The major clinical symptoms were diarrhea （100.0%）， stomachache （100.0%）， and vomiting （41.7%）. Samples from 24 patients were tested positive for Vibrio parahaemolyticus， and were homologous by Pulsed field gel electrophoresis （PFGE） phylogenetic study. According to the result of case-control study， eating glass noodles salad at the dinner and supper on July 16th， 2019 was the risk factor （OR=15.71，95%CI：1.90‒129.71）. ConclusionThis foodborne disease outbreak was caused by glass noodles salad cross contaminated with Vibrio parahaemolyticus.

In recent years, as the study of molecular mechanism and signal transduction pathways of tumors, mo-lecular target therapy in many solid tumors has made great progress. At present, more and more studies focus on molecular tar-get drugs in thymic epithelial tumors and people have got some experience. Molecular target therapy may be a new therapeutic option for patients of thymic epithelial tumor.