BACKGROUND:Patellar tendonitis can present as tendon degeneration that fails to heal due to tissue overload and incomplete recovery.Patellar tendonitis is a predisposition to high jumping and its pathogenesis has not been clearly defined.OBJECTIVE:To explore the stress-strain relationship of patellar tendon in the take-off technique of high jump through the finite element model with accurate human anatomical structure,so as to provide ideas for the prevention and rehabilitation of patellar tendinitis.METHODS:Based on the CT and MRI imaging data of the lower extremity(including the knee and ankle)of one subject(22 years old,183 cm height,70 kg body mass),a three-dimensional finite element model of the lower extremity was reconstructed using medical imaging software,reverse engineering software and modeling software.The plantar pressure of the take-off leg was collected in eight subjects by gait testing system,and the technical action of high jump take-off was collected by motion capture system.The captured data were imported into human sports biomechanics software for analysis,and kinematic and kinetic data were obtained as the boundary conditions of finite element model for finite element simulation analysis.RESULTS AND CONCLUSION:The force borne by the patellar tendon reached 3.29 times of its own body mass when the subjects took off.In the take-off stage,the peak values of normal equivalent stress,strain and shear stress of the patellar tendon were 127.76 MPa,0.81 and 37.69 MPa,respectively,which were in the nonlinear region of the stress-strain curve,and the peak values were distributed in the proximal and posterior parts of patellar tendon.To conclude,the high patellar tendon force,strain and shear stress caused by the load of 3.29 times its own body mass during take-off are related to the induction of patellar tendinitis.

BACKGROUND:Patellar tendonitis can present as tendon degeneration that fails to heal due to tissue overload and incomplete recovery.Patellar tendonitis is a predisposition to high jumping and its pathogenesis has not been clearly defined.OBJECTIVE:To explore the stress-strain relationship of patellar tendon in the take-off technique of high jump through the finite element model with accurate human anatomical structure,so as to provide ideas for the prevention and rehabilitation of patellar tendinitis.METHODS:Based on the CT and MRI imaging data of the lower extremity(including the knee and ankle)of one subject(22 years old,183 cm height,70 kg body mass),a three-dimensional finite element model of the lower extremity was reconstructed using medical imaging software,reverse engineering software and modeling software.The plantar pressure of the take-off leg was collected in eight subjects by gait testing system,and the technical action of high jump take-off was collected by motion capture system.The captured data were imported into human sports biomechanics software for analysis,and kinematic and kinetic data were obtained as the boundary conditions of finite element model for finite element simulation analysis.RESULTS AND CONCLUSION:The force borne by the patellar tendon reached 3.29 times of its own body mass when the subjects took off.In the take-off stage,the peak values of normal equivalent stress,strain and shear stress of the patellar tendon were 127.76 MPa,0.81 and 37.69 MPa,respectively,which were in the nonlinear region of the stress-strain curve,and the peak values were distributed in the proximal and posterior parts of patellar tendon.To conclude,the high patellar tendon force,strain and shear stress caused by the load of 3.29 times its own body mass during take-off are related to the induction of patellar tendinitis.

Objective : To investigate the status of electronic cigarette use and its influencing factors among residents aged ≥15 years in Chengdu City in 2021 and 2024, so as to provide the evidence for optimizing electronic cigarette control strategies. Methods: Two rounds of cross-sectional surveys were conducted in 2021 and 2024. Multi-stage cluster random sampling method was used to select permanent residents aged ≥15 years in Chengdu City as survey subjects. The Chinese Adult Tobacco Survey Questionnaire was used to collect information on gender, age, and electronic cigarette use. Complex sampling weighting was used to calculate the rate of electronic cigarette use and the proportion of reasons for electronic cigarette use. A complex sampling multivariable logistic regression model was used to analyze the influencing factors for electronic cigarette use. Results: A total of 7 950 and 6 920 people were surveyed in 2021 and 2024, respectively, including 3 868 and 3 653 males (48.65% and 52.79%), and 4 082 and 3 267 females (51.35% and 47.21%), respectively. The rate of electronic cigarette use in 2024 was lower than in 2021 (2.29% vs. 3.15%, P<0.05). In 2024, the rates of electronic cigarette use were lower in males, rural areas, people aged 15-<45 years, educational level of bachelor' s degree or above, occupation in government/public institutions or occupation in enterprises/commercial/service industries, and current smokers compared with 2021, while the rate of electronic cigarette use was higher in residents aged ≥65 years compared with 2021 (all P<0.05). In 2021 and 2024, the main reasons for electronic cigarette use were smoking cessation and the belief that electronic cigarettes are less harmful. Smoking cessation accounted for 27.78% and 23.28%, and the belief that electronic cigarettes are less harmful accounted for 24.26% and 22.10%, respectively. Complex sampling multivariable logistic regression analysis showed that age (15-<25 years, OR=15.682, 95%CI: 5.660-43.450; 25-<45 years, OR=7.463, 95%CI: 2.987-18.647; 45-<65 years, OR=3.425, 95%CI: 1.562-7.510), educational level (bachelor' s degree or above, OR=2.916, 95%CI: 1.444-5.891), and smoking (current, OR=23.992, 95%CI: 8.182-70.353; former, OR=20.393, 95%CI: 6.150-67.624) were influencing factors for electronic cigarette use in 2021. Gender (male, OR=2.279, 95%CI: 1.074-4.832), age (25-<45 years, OR=2.114, 95%CI: 1.148-3.892), educational level (high school/vocational high school/technical secondary school, OR=2.792, 95%CI: 1.414-5.514; bachelor' s degree or above, OR=3.321, 95%CI: 1.567-7.039), occupation (unemployed, retired, and retired, OR=0.449, 95%CI: 0.226-0.892), and smoking (current, OR=10.547, 95%CI: 5.563-19.994; former, OR=8.998, 95%CI: 3.833-21.125) were influencing factors for electronic cigarette use in 2024. Conclusions Compared with 2021, the rate of electronic cigarette use among residents in Chengdu City decreased in 2024. Young people, males, bachelor' s degree or above, and current smokers are the key populations for electronic cigarette control. The cognitive bias held by residents that electronic cigarette can aid in smoking cessation and pose minimal harm needs to be corrected.

ObjectiveTo observe the effect of neural mobilization based on shoulder control training on shoulder pain and upper limb function in stroke patients with hemiplegia. MethodsFrom January, 2020 to November, 2021, 43 patients with hemiplegia after stroke in the Second People's Hospital of Nantong were randomly divided into control group (n = 21) and treatment group (n = 22). The control group received shoulder control training, while the treatment group received neural mobilization in addition. Before and after four weeks of treatment, they were evaluated with the Numeric Rating Scale (NRS) of pain and Fugl-Meyer Assessment-Upper Extremities (FMA-UE). ResultsOne case dropped off in the control group and two cases dropped off in the treatment group. After treatment, the NRS score and FMA-UE score improved in both groups (|t| >7.898, P < 0.001), and they were better in the treatment group than in the control group (|t| >2.337, P < 0.05). ConclusionNeural mobilization based on shoulder control training can significantly alleviate shoulder pain and improve upper limb motor function in stroke patients with hemiplegia.

In recent years , there are increasing articles concerning Epstein-Barr virus associated lymphoproliferative disorder (EBV+LPD), and the name of EBV +LPD is used widely.However,the meaning of EBV+LPD used is not the same , which triggered confusion of the understanding and obstacles of the communication.In order to solve this problem.Literature was reviewed with combination of our cases to clarify the concept of EBV +LPD and to expound our understanding about it .In general, it is currently accepted that EBV +LPD refers to a spectrum of lymphoid tissue diseases with EBV infection , including hyperplasia , borderline lesions , and neoplastic diseases .According to this concept , EBV+LPD should not include infectious mononucleosis ( IM ) and severe acute EBV infection ( EBV +hemophagocytic lymphohistiocytosis, fatal IM, fulminant IM, fulminant T-cell LPD), and should not include the explicitly named EBV+lymphomas ( such as extranodal NK/T cell lymphoma , aggressive NK cell leukemia , Burkitt lymphoma, and Hodgkin lymphoma , etc.) either.EBV +LPD should currently include: ( 1 ) EBV +B cell-LPD:lymphomatoid granulomatosis , EBV +immunodeficiency related LPD , chronic active EBV infection-B cell type, senile EBV +LPD, etc.(2) EBV +T/NK cell-LPD:CAEBV-T/NK cell type, hydroa vacciniforme, hypersensitivity of mosquito bite, etc.In addition, EBV+LPD is classified, based on the disease process , pathological and molecular data , as 3 grades:grade1, hyperplasia ( polymorphic lesions with polyclonal cells ); grade 2, borderline ( polymorphic lesions with clonality ); grade 3, neoplasm (monomorphic lesions with clonality).There are overlaps between EBV +LPD and typical hyperplasia, as well as EBV+LPD and typical lymphomas .However , the most important tasks are clinical vigilance , early identification of potential severe complications , and treating the patients in a timely manner to avoid serious complications , as well as the active treatment to save lives when the complications happened .