OBJECTIVE:To investigate the inhibitory effects mechanism of scallop skirt glycosaminoglycan(SS-GAG)on inju-ry in human umbilical vein endothelium cells (HUVEC). METHODS:In the test,there was a negative control group,a model group and the groups of SS-GAG at high,middle and low concentrations(mass concentrations of 200,100 and 50 mg/L respective-ly). The cells in latter 3 groups were cultured in SS-GAG at different mass concentrations for 12 h,and then in 50 μmol/L oxidized low-density lipoprotein(OX-LDL)for 24 h. MTT method was used to detect cell viability and the activity of lactic dehydrogenase (LDH),the flow cytometer to determine the level of reactive oxygen species (ROS),real-time fluorescence quantitative poly-merase chain reaction (RT-PCR) to detect mRNA expression of lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1), and Western blot to detect NOX4 protein expression. RESULTS:Compared to the cells in the negative control group,those in the model group demonstrated lower viability,higher activity of LDH,higher level of ROS,and stronger expressions of LOX-1 mRNA and NOX4 protein. There was statistical significance (P<0.01). Compared to the cells in the model group,those in the groups of SS-GAG at high,middle and low concentrations showed higher viability,lower activity of LDH,lower level of ROS and weaker expressions of LOX-1 mRNA and NOX4 protein. There was statistical significance (P<0.01). CONCLUSIONS:SS-GAG can protect HUVEC to some degree by a mechanism which may be related to inhibiting ROS production via LOX-1/NOX4 pathway and relieving oxidative stress injury.

Objective:To survey the status quo of family doctor work mode in Shanghai Xuhui district.Methods:Semi-structured and structured in-depth interviews were conducted in Shanghai Xuhui district from April to June 2021, 11 directors, 12 deputy directors in charge and 30 family doctors from 12 community health service centers participated in the survey and completed two stages and four sessions of interviews on the development of the integrated and high-quality family doctor work mode and the ways to realize and the challenges to face. The records of interviews were transcribed, sorted and analyzed using the Colaizzi 7-step analysis method.Results:The survey showed that the family doctor contracting was carried out in a large team mode in the whole district, mainly for the elderly, and most of contracted residents were not included in health management and follow-up services. The team was composed of family doctors and assistants, and the routine outpatient service was the main work pattern, and the regular services also included the chronic disease follow-up and health check-up for elderly. On the issue of how to output high-quality integrated services, the majority of doctors (12/13) believed that the contracted individual should be taken as the unit of fine service, carrying out overall health assessment, optimizing medication plan, lifestyle guidance, one-stop service in hospital, etc.; only one doctor suggested that the family should be the management unit. For upgrading the working mode and service quality, insufficient time and energy were the main obstacle. Public health work occupied a lot of working time, but it seemed not be transformed into favorable resources and conveniences in health management and services. The professional assistants should carry out some responsibility to save family doctor′s time. The survey suggests that informatization, service space, and sufficient drug supply are the keys for ensuring high-quality and high-efficiency integrated services.Conclusion:The organizational structure of the family doctor team in Shanghai Xuhui district is relatively mature, but the integrated and high-quality service output has not yet reached. It is necessary to make regional overall planning and increase efforts to achieve the integration of medical treatment and prevention, so as to gain time for family doctors to carry out high-quality services. At the same time, it is also necessary to cultivate effective family doctor assistants, provide an information work platform that matches the work attributes and goals of family doctors, open up an integrated health management service space, and ensure the full range supply of drugs.

Objective To establish an ideal model of the mitral valve,including the left heart and blood,and study the motion characteristics of the mitral valve in blood flow using the fluid-structure interaction(FSI)simulation.Methods Based on anatomical parameters,models of the mitral valve,left heart,and blood were established.The finite-elements combined immersed boundary method was used for FSI to simulate the motion of the mitral valve using the LS-DYNA software.Morphological,mechanical,and hemodynamic parameters were compared with those obtained from structural simulations.Results The morphological results of the mitral valve from the two simulations differed significantly,and the FSI results matched the ultrasound images.The stress distributions of the leaflets in the FSI and structural simulations were consistent.The maximum first principal stresses calculated by FSI and structural simulations were 1.48 MPa and 1.53 MPa,respectively,with a relative error of 3.27％.The fluid field in the left heart was complex with vortex structures,and the maximum mitral flow velocity was 1.02 m/s during diastole,consistent with the physiological data of healthy humans(0.89±0.15 m/s).Conclusions The morphological results of the mitral valve obtained from the FSI simulation were closer to those in the physiological state.FSI simulations can provide flow patterns that are indispensable for clinical diagnosis.Structural simulations are more efficient for studying leaflet stress distribution.

Objective:To investigate the clinical efficacy of arthroscopic surgery for the treatment of femoral acetabular impingement (FAI) in athletes.Methods:A total of 18 FAI athletes (athlete group) who underwent hip arthroscopy in the Department of Sports Medicine, Peking University Third Hospital from April 2014 to June 2021 were retrospectively analyzed, including 12 males and 6 females, aged 20.44±3.45 years (range, 15-27 years). According to gender, age, body mass index and follow-up time, 36 non-athlete FAI patients (non-athlete group) were matched at a ratio of 1∶2 by propensity score matching method. There were 18 males and 18 females, aged 20.81±4.68 years (range 14-31 years). The hip pain visual analogue scale (VAS), modified Harris hip score (mHHS), hip outcome score-activity of daily living scale (HOS-ADL) and hip outcome score-sports scale (HOS-SS) scores were compared between the two groups before and after surgery. The minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) were also compared between the two groups.Results:All patients successfully completed the surgery and were followed up for 33.56±19.20 months (range, 24-77 months). The VAS score at the last follow-up decreased from 6.22±1.52 points before surgery to 1.28±1.67 points in the athletes group, and decreased from 6.28±1.37 points before surgery to 1.67±1.69 points in the non-athletes group. There was no significant difference between the two groups ( P>0.05). The mHHS score at the last follow-up increased from 65.53±12.90 points before surgery to 92.28±13.59 points in the athletes group, and increased from 61.01±11.96 points before surgery to 86.82±11.98 points in the non-athletes group. There was no significant difference between the two groups ( P>0.05). The HOS-ADL score at the last follow-up increased from 72.77±18.86 points before surgery to 94.00±11.36 points in the athletes group, and increased from 70.35±13.12 points before surgery to 90.78±9.36 points in non-athletes group. There was no significant difference between the two groups ( P>0.05). The HOS-SS score at the last follow-up increased from 49.77±22.93 points before surgery to 87.28±17.62 points in the athletes group, and increased from 44.08±19.66 before surgery to 72.57±20.16 in the non-athletes group. The HOS-SS scores in the athletes group at the last follow-up were higher than those in the non-athletes group ( P<0.05). Furthermore, 61% (11/18) in the athletes group achieved MCID in HOS-ADL after surgery, which was lower than the non-athletes group's 81% (31/36), with a statistically significant difference (χ 2=4.339, P=0.037). Conclusion:Hip arthroscopy in the treatment of FAI in athletes can achieve satisfactory pain relief and motor function.