Objective:A microsurgical simulation training device based on real clinical scenes was designed and its effectiveness was tested.Methods:From January 1, 2020 to January 1, 2023, postgraduate students in the Plastic and Reconstructive Surgery Department of the First Medical Center of PLA General Hospital and the Plastic Surgery Hospital of Chinese Academy of Medical Sciences were enrolled in this prospective study. The simulation training device consists of four parts: (1)Blood perfusion system, which is used to simulate living animal blood vessels.(2)The inner baffling rod system, which is used to simulate the operation in deep cavity.(3) The exterior baffling rod system, which is used to simulate the operation in difficult positions.(4) A pulsating platform system is used to simulate microsurgery under the influence of respiratory movement. Preliminary verification of the effect of the simulated training device was as follows: Surgeons with no experience in microsurgery were completely randomized assigned to the control group (traditional microsurgery training group) and the experimental group (training group using the simulated training device). After 4 weeks of microsurgical training, the trainees were assigned to perform two surgical skill assessments, the first using a live animal model for end-to-end anastomosis of rat tail arteries, and the second assessment using end-to-end anastomosis of free latissimus dorsi flap arteries in a real case. The performance of the two groups was compared by using operation time and microsurgical GRS score scale including four items of dexterity, visuospatial ability, operative flow and judgment. Chi-squared test was used to analyze gender between the two groups. GRS scores between the two groups were compared by the Mann-Whitney U test. Participants’ ageand operation time between the two groups was compared by independent t-test. P<0.05 was considered statistically significant. Results:A total of 18 trainees were enrolled, including 10 in the control group, 6 males and 4 females, with an average age of (27.80±1.87) years. There were 8 subjects in the experimental group, 4 males and 4 females, with an average age of (28.10±1.56) years old. There were no significant differences in age, gender and other baseline characteristics between the two groups ( P>0.05). There was no significant difference in GRS score and operation time between the control group and the experimental group ( P> 0.05) in the first assessment. However, in the second assessment of real cases, the GRS score of the experimental group was significantly higher than that of the control group(14.25 vs. 5.70), and the operation duration of the experimental group was also shorter than that of the control group, and the difference was statistically significant[(100.37±24.65 ) min vs. (105.60±22.84) min] ( P<0.05). Conclusion:Compared with traditional microsurgery training methods, using microsurgery training devices based on clinical real scenes can effectively shorten the learning curve and enable trainees to master complex micromanipulation skills more quickly.

Intracranial atherosclerosis has been regard as the most common cause of ischemic stroke.The information of the types and degree of vascular wall lesions is important basis for the diagnosis and treatment of ischemic stroke.High-resolution MR vessel wall imaging can directly display the lumen and wall of intracranial vessels,evaluate the characteristics of atherosclerotic plaque qualitatively and quantitatively,including intra-plaque hemorrhage,plaque enhancement,and plaque distribution.Thus,high-resolution MR vessel wall imaging may play an important role in risk stratification,pathogenesis,treatment and prognosis evaluation in ischemic stroke patients.This review summarizes the progress of high-resolution MRI vessel wall imaging in the evaluation of intracranial atherosclerosis,especially the pathogenesis of plaque features and treatment-related information.

Objective:A microsurgical simulation training device based on real clinical scenes was designed and its effectiveness was tested.Methods:From January 1, 2020 to January 1, 2023, postgraduate students in the Plastic and Reconstructive Surgery Department of the First Medical Center of PLA General Hospital and the Plastic Surgery Hospital of Chinese Academy of Medical Sciences were enrolled in this prospective study. The simulation training device consists of four parts: (1)Blood perfusion system, which is used to simulate living animal blood vessels.(2)The inner baffling rod system, which is used to simulate the operation in deep cavity.(3) The exterior baffling rod system, which is used to simulate the operation in difficult positions.(4) A pulsating platform system is used to simulate microsurgery under the influence of respiratory movement. Preliminary verification of the effect of the simulated training device was as follows: Surgeons with no experience in microsurgery were completely randomized assigned to the control group (traditional microsurgery training group) and the experimental group (training group using the simulated training device). After 4 weeks of microsurgical training, the trainees were assigned to perform two surgical skill assessments, the first using a live animal model for end-to-end anastomosis of rat tail arteries, and the second assessment using end-to-end anastomosis of free latissimus dorsi flap arteries in a real case. The performance of the two groups was compared by using operation time and microsurgical GRS score scale including four items of dexterity, visuospatial ability, operative flow and judgment. Chi-squared test was used to analyze gender between the two groups. GRS scores between the two groups were compared by the Mann-Whitney U test. Participants’ ageand operation time between the two groups was compared by independent t-test. P<0.05 was considered statistically significant. Results:A total of 18 trainees were enrolled, including 10 in the control group, 6 males and 4 females, with an average age of (27.80±1.87) years. There were 8 subjects in the experimental group, 4 males and 4 females, with an average age of (28.10±1.56) years old. There were no significant differences in age, gender and other baseline characteristics between the two groups ( P>0.05). There was no significant difference in GRS score and operation time between the control group and the experimental group ( P> 0.05) in the first assessment. However, in the second assessment of real cases, the GRS score of the experimental group was significantly higher than that of the control group(14.25 vs. 5.70), and the operation duration of the experimental group was also shorter than that of the control group, and the difference was statistically significant[(100.37±24.65 ) min vs. (105.60±22.84) min] ( P<0.05). Conclusion:Compared with traditional microsurgery training methods, using microsurgery training devices based on clinical real scenes can effectively shorten the learning curve and enable trainees to master complex micromanipulation skills more quickly.

Objective: An isochronous substitution model was established to explore the association and substitution effect between college students 24 hour activity behavior and physical health, so as to provide specific activity behavior suggestions for college students to improve their physical health. Methods: A stratified random cluster sampling method was used to conduct physical fitness tests and 24 hour activity behavior surveys among 2 794 college students in 12 colleges and universities in Tianjin.Time spent on sedentary behavior(SB), light intensity physical activity(LPA), moderate to vigorous physical activity(MVPA) and sleep(SLP) time. The isochronous method of components was used to explore the relationship between 24 h activity behavior and physical health. Results: Except for 50 m running, MVPA was negatively correlated with BMI Z ( β =-0.62, P <0.05), but positively correlated with other physical fitness indexes ( β =0.34~274.23, P <0.05). LPA was not associated with lung capacity, sitting forward flexion and 50 m running, and negatively correlated with other physical fitness indexes ( β =-14.30- -0.19, P <0.05). SB was negatively correlated with most physical fitness indexes ( β =-11.57- -0.33, P <0.05), but positively correlated with BMI Z ( β =0.45, P < 0.05 ). In addition to lung capacity, SLP was positively correlated with BMI Z , total physical fitness score,1 minute sit-ups, pull ups, 800/1 000 m running, sitting forward flexion, and 50 m running ( β =0.27-11.21, P <0.05), but negatively correlated with long jump ( β =-0.10, P <0.05）. Isochronous substitution showed that the adverse effects of 30 min/d SB and LPA substitution of MVPA were much greater than the beneficial effects of MVPA substitution for corresponding behaviors (total physical score: SB, -0.58 vs 0.47 points; LPA, -0.50 vs 0.38 points). Conclusion MVPA and SLP have been found to have a positive effect on physical fitness among college students. Therefore, in the process of improving the physical health of college students, ensuring adequate sleep, improving MVPA and reducing SB as much as possible may be one of the effective methods.

Objective: To explore the relationship between isochronous substitution and BMI, waist circumference (WC), and body fat rate (FAT) among physical activity (PA), sedentary (SB), and sleep (SLP), so as to provide effective measures for obesity control in adolescents. Methods: A total of 193 adolescents aged 12-15 (90 males and 103 females) was randomly selected, and their height, weight, and BMI were measured using routine testing methods from May to August 2022. The PA, SB and SLP of the participants were measured using a 3D accelerometer (ActiGraph GT3X+). Results: The arithmetic mean value overestimated SLP (40.8%) and SB (39.6%) to some extent, and underestimated LPA (16.1%) and MVPA (3.5%) to some extent. Based on the ISM at 15 min, MVPA was substituted for other activity, BMI Z decreased by 0.17-0.22 units, WC Z decreased by 0.16-0.20 units, and FAT Z decreased by 0.17-0.22 units. The substitution between MVPA and for other activity exhibited significant asymmetry. The effects of MVPA substitutions for SB was the largest, followed by the effects of MVPA substitutions for SLP, and the effects of MVPA substitutions for LPA was the lowest. As MVPA substitutions for other behaviors, it reached its maximum (0.06-0.08 units ) when the MVPA time increased by 5 minutes. Conclusions MVPA plays an irreplaceable role in the control of adolescent obesity . While reducing SB time, MVPA duration should be increased to ensure that the daily MVPA duration is not less than 55 minutes in order to effectively control obesity.

Objective:To investigate effects of metformin and rosiglitazone in non-obese polycystic ovary syndrome (PCOS) women with insulin resistance.Methods:Totally 200 non-obese PCOS women with insulin resistance in West China Second Hospital of Sichuan University were enrolled into this study from Sep. 2013 to Jun. 2016, and were randomly divided into two treatment groups: metformin group (1 500 mg/d) and rosiglitazone group (4 mg/d). The treatment lasted for 6 months. Their clinical and biochemical parameters were collected and compared.Results:In both groups, menstrual cycles [metformin group (37±4) days, rosiglitazone group (35±4) days] were shorter after treatment for 6 months (both P<0.01). After treatment for 6 months, body mass index [metformin group (21.6±1.6) kg/m 2, rosiglitazone group (21.7±1.7) kg/m 2] decreased in both groups (both P<0.01); decreased LH/FSH ratio (metformin group 1.67±0.80, rosiglitazone group 1.70±0.83) was also observed (both P<0.05). After treatment for 6 months, fasting insulin level [metformin group (13.5±5.1) mU/L, rosiglitazone group (12.7±5.6) mU/L] and homeostasis model assessment-insulin resistance index (metformin group 3.0±1.2, rosiglitazone group 2.8±1.2) were decreased in both groups (all P<0.01). Conclusions:For non-obese PCOS insulin resistance patients, screening of anthropometric and metabolic parameters is necessary. For PCOS with insulin resistance, lifestyle plus insulin sensitizers such as metformin could improve their clinical symptoms, correct the biochemical and metabolic dysfunction.

Ischemic stroke is one of the most important causes of death and disability in humans,but the effective methods for treating brain injury after stroke are quite limited.Sphingosine 1-phosphate (S1P) is a pleiotropic lipid.There is certain interdependence between its metabolism and regulation and the molecular mechanisms involved in important biological events following cerebral ischemia.Membrane lipid therapy with S1P as the core may be an effective neuroprotective strategy of ischemic stroke.

Genetic mutations in triggering receptor expressed on myeloid cells 2 (TREM2) have been linked to a variety of neurodegenerative diseases including Alzheimer’s disease, amyotrophic lateral sclerosis, frontotemporal dementia and Parkinson’s disease. In the brain, TREM2 is highly expressed on the cell surface of microglia, where it can transduce signals to regulate microglial functions such as phagocytosis. To date, mechanisms underlying intracellular trafficking of TREM2 remain elusive. Mutations in the presenilin 1 (PS1) catalytic subunit of the γ-secretase complex have been associated with increased generation of the amyloidogenic Aβ (amyloid-β) 42 peptide through cleavage of the Aβ precursor amyloid precursor protein. Here we found that TREM2 interacts with PS1 in a manner independent of γ-secretase activity. Mutations in TREM2 alter its subcellular localization and affects its interaction with PS1. Upregulation of PS1 reduces, whereas downregulation of PS1 increases, steady-state levels of cell surface TREM2. Furthermore, PS1 overexpression results in attenuated phagocytic uptake of Aβ by microglia, which is reversed by TREM2 overexpression. Our data indicate a novel role for PS1 in regulating TREM2 intracellular trafficking and pathophysiological function.

Neuromyelitis optica spectrum disorder (NMOSD) is a kind of immune mediated inflammatory demyelinating disease of the central nervous system manifesting with optic neuritis and acute transverse myelitis,which takes a relapsing or progression course.The exact etiology and pathogenesis are not clear.There are a lot of researches on immune pathogenesis;in addition,the pathogenesis also involves genetic,environmental,oxidative stress and other factors.

Objective To evaluate the feasibility and safety of a delivery pathway for the performance of percutaneous left atrial appendage (LAA) occlusion in experimental canine models. Methods Transseptal puncture was performed via femoral vein approach under fluoroscopic and angiographic guidance in 12 experimental dogs. A pigtail catheter was advanced into the left atrium (LA), which was followed by LA angiography. The diameters of the neck of LAA were measured on LAA angiogram obtained in appropriate projection. After the delivery sheath was advanced along the wire into LA, a pigtail catheter was inserted into the ostium of the LAA and the sheath was then advanced over the pigtail into the LAA. LAA angiography was then performed through the delivery sheath to confirm the position of the delivery sheath. One hour after the procedure both electrocardiography (ECG) and transthoracic echocardiography (TTE) were carried out in five dogs to check the results, immediately after which the five dogs were sacrificed to macroscopically observe the damages of the puncture site of inter-atrial septum as well as inside the LA and LAA. One hour and 2 weeks after the procedure TTE was conducted in the remaining 7 dogs and these dogs were followed up for one month. Results One dog died of pericardial tamponade during the operation. In 8 dogs the LAA was clearly displayed in the projection position of right anterior oblique (RAO) 30°/cranial (CRA) 20°,while in 3 dogs the LAA was well visualized in the projection position of RAO 30° , and in one dog in the projection position of RAO 30°/caudal (CAU) 20°. The diameter of LAA neck was (13.6 ± 5.2) mm. The delivery sheath was safely advanced into the LAA along the pigtail catheter in all dogs, and no air embolism, thrombus or pericardial tamponade occurred. Hematoma at puncture point of groin occurred in 2 dogs, which was absorbed through pressure dressing. Macroscopic examination of the heart performed immediately after the operation showed that no bloody pericardial effusion was found, and mild hematoma at posterior wall of LA was seen in one dog and mild damage of the upper-margin intima of LAA was noted in 2 dogs. The mean fluoroscopy time was (10.1 ± 2.5) minutes and the mean operation time was (58 ± 12) minutes. TEE showed no pericardial effusion 2 weeks after the procedure. During the follow-up period of one month no sudden death, stroke or infection occurred. Conclusion This method of placing the delivery sheath into the LAA is clinically safe and effective, and it can reliably establish a pathway to advance the LAA occluder into LAA.