1.Computer-aided design of an improved lamina hook and finite element analysis of its use in fixation of lumbar spondylolysis
Hongliang GAO ; Hua LIU ; Tao ZHANG ; Chengwei YANG ; Yizhe WANG ; Zirong HUANG ; Wenhua ZHANG ; Long CHEN ; Bing KANG ; Yuxuan MA ; Songkai LI
Chinese Journal of Trauma 2024;40(7):593-604
Objective:To design an improved lamina hook system and compare its biomechanical properties with traditional lamina hook system in fixation of lumbar spondylolysis.Methods:The thin layer CT data of the lumbosacral vertebrae of 20 healthy young male servicemen who underwent physical examination in the outpatient department of the 940th Hospital of Joint Logistics Support Force of PLA from January 2021 to August 2022 were collected. The age of the subjects was 20-30 years [(25.0±3.0)years]. A 3-dimensional model of the L 5 vertebral body was constructed using the 3-dimensional modeling software. The new improved lamina hook was designed according to the measurements including the thickness of the middle area, the longest longitudinal diameter, the curvature radius of the lower edge, the angle between the upper and lower tail ends, the thickness of the lower edge, and the longest diameter of the lower edge of the bilateral L 5 vertebral plates. One serviceman was selected from the aforementioned group to construct a linear finite element model of segments L 4-S using the 3-dimensional virtual software (normal model, model A), based on which, the L 5 bilateral spondylolysis model (model B), improved lamina hook model (model C) and traditional lamina hook models (model D) were designed. By constraining both sides of the sacrum and applying a longitudinal load of 400 N on the L 4 vertebral body, the upper 1/3 gravity of the body was simulated, and with a bending moment of 10 N·m along the X, Y, and Z directions, motions of forward flexion, backward extension, lateral bending, rotation, etc were simulated. The range of motion of segment L 4/5 and L 5/S 1 of model A was evaluated and compared with the findings of the previous researches to verify its effectiveness. The overall range of motion of models A, B, C, and D, the range of motion of segment L 4/5 and L 5/S 1, the maximum overall displacement, the maximum displacement and stress of the isthmus, the stress distribution and maximum stress of internal fixation of models C and D, and the stress distribution and maximum stress of the vertebral body of models C and D were compared. Results:(1) During forward flexion, backward extension, lateral bending and rotation, the range of motion of model A was 5.01°, 4.03°, 3.91° and 1.42° in segment L 4/5, and was 4.62°, 2.51°, 2.40° and 1.23° in segment L 5/S 1. (2) The overall range of motion, range of motion of segment L 4/5 and L 5/S 1 and maximum overall displacement of models A, C, and D were similar in axial compression, forward flexion, backward extension, left bending, and left rotation, while those of model B were significantly increased. (3) There was no significant difference in the maximum displacement of the isthmus of models A, C, and D under different motion modes, while the maximum displacement of model B in the isthmus was significantly larger than that of models A, C, and D, especially during rotation, increased by 295%, 277%, and 276% respectively. The maximum stress of the isthmus of model C was 0.938 MPa, 1.698 MPa, 0.410 MPa, 2.775 MPa, and 1.554 MPa respectively. The maximum stress in the isthmus of model D was 0.590 MPa, 1.297 MPa, 0.520 MPa, 3.088 MPa, and 2.072 MPa respectively. The maximum stress of the isthmus of models C and D was similar during axial compression and forward flexion, while the stress of the isthmus of model C was smaller than that of model D during backward extension, lateral bending, and rotation, decreased by 21.1%, 10.2%, and 25.0% respectively compared with model D. (4) The maximum stress of internal fixation in models C and D during forward flexion, backward extension, left bending, and left rotation was 135.220 MPa, 130.180 MPa, 200.940 MPa and 306.340 MPa respectively, and was 131.840 MPa, 112.280 MPa, 349.980 MPa and 370.140 MPa respectively. The maximum stress of internal fixation in the two models of internal fixation during forward flexion and backward extension was similar, while it was decreased by 42.6% and 17.2% in model C during left bending and left rotation, compared with model D. (5) The maximum stress of the vertebral body during forward flexion, backward extension, left bending, and left rotation was 79.787 MPa, 36.857 MPa, 37.943 MPa and 96.965 MPa respectively in model C, but was 80.104 MPa, 64.236 MPa, 196.010 MPa and 193.020 MPa respectively in model D. The maximum stress of models C and D was all distributed in the contact area with the internal fixation, and especially during backward extension, left bending, and left rotation, when it was reduced by 42.6%, 80.6%, and 49.8% of model C respectively, compared with that of model D. Conclusions:The improved laminar hook is more consistent with the Chinese anatomized structure of the lamina. Compared with the traditional lamina hook system, the improved lamina hook system can effectively reduce the displacement in all directions and range of motion of lumbar spondylolysis, therefor can significantly reduce the stress of internal fixation and vertebral body and has better biomechanical performance.
2.Exploration of models of radiosensitive lipid metabolites of human plasma based on multiple machine learning algorithms
Qi CHEN ; Hua ZHAO ; Tianjing CAI ; Yizhe GAO ; Ling GAO ; Qingjie LIU
Chinese Journal of Radiological Medicine and Protection 2024;44(6):457-463
Objective:To explore classification models for radiosensitive lipid metabolites in human peripheral blood by combining lipidomics with multiple machine learning (ML) algorithms.Methods:Totally 97 peripheral blood samples were collected from 25 leukemia cases admitted to a general hospital in Beijing from March to September 2023 who were ready to undergo bone marrow transplantation, including 0 Gy blood samples before irradiation in the control group ( n=24), and 73 blood samples after irradiation at doses of 4, 8 and 12 Gy in the radiation group ( n=73), and the targeted lipidomic based on the ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) platform method to analyze the differences of different lipids between control and radiation groups. Then, lipids responsive to radiation doses of 0-12 Gy were identified using linear regression. Finally, classification models were constructed using five ML algorithms based on the training set, followed by the validation and evaluation of these models using the validation set. Results:Compared with the control group, the differences in the concentration changes of 62 lipids in 9 classes of lipid metabolites sensitive to radiation group were statistically significant ( t=-4.91 to 4.74, P<0.05), including sphingomyelins(SMs), cholesteryl esters(CEs), ceramides(Cers), phosphatidylinositols(PIs), hexosylceramides(HexCers), lysophosphatidylcholines (LysoPCs), phosphatidylcholines (PCOs), phosphatidylethanolamines (PEs), and lysophosphatidylethanolamines (LysoPEs). Twenty lipids responsive to radiation doses of 0-12 Gy were identified, namely 11 SMs, 7 CEs, 1 Cer, and 1 PI. The five models based on ML algorithms of decision tree (DT), support vector machine (SVM), light gradient boosting machine (Light GBM), random forest (RF), and K-nearest neighbors (KNN) all exhibited high goodness of fit (F1=0.69-1.00) and high sensitivity. The evaluation and validation metrics revealed that the RF-based model yielded the optimal radiation classification discrimination (sensitivity: 1.00; accuracy: 0.72; F1 score: 0.80). Conclusions:Lipid metabolites responsive to radiation and lipids responsive to radiation dose in human samples were identified using targeted lipidomics. The RF-based model can provide new ideas for exploring models of human radiosensitive lipid metabolites.
3.A novel intracoronary hypothermia device reduces myocardial reperfusion injury in pigs
Zhiqiang PEI ; Jin QIU ; Yongchao ZHAO ; Shuai SONG ; Rui WANG ; Wei LUO ; Xingxing CAI ; Bin LIU ; Han CHEN ; Jiasheng YIN ; Xinyu WENG ; Yizhe WU ; Chenguang LI ; Li SHEN ; Junbo GE
Chinese Medical Journal 2024;137(20):2461-2472
Background::Hypothermia therapy has been suggested to attenuate myocardial necrosis; however, the clinical implementation as a valid therapeutic strategy has failed, and new approaches are needed to translate into clinical applications. This study aimed to assess the feasibility, safety, and efficacy of a novel selective intracoronary hypothermia (SICH) device in mitigating myocardial reperfusion injury.Methods::This study comprised two phases. The first phase of the SICH was performed in a normal porcine model for 30 minutes ( n = 5) to evaluate its feasibility. The second phase was conducted in a porcine myocardial infarction (MI) model of myocardial ischemia/reperfusion which was performed by balloon occlusion of the left anterior descending coronary artery for 60 minutes and maintained for 42 days. Pigs in the hypothermia group ( n = 8) received hypothermia intervention onset reperfusion for 30 minutes and controls ( n = 8) received no intervention. All animals were followed for 42 days. Cardiac magnetic resonance analysis (five and 42 days post-MI) and a series of biomarkers/histological studies were performed. Results::The average time to lower temperatures to a steady state was 4.8 ± 0.8 s. SICH had no impact on blood pressure or heart rate and was safely performed without complications by using a 3.9 F catheter. Interleukin-6 (IL-6), tumor necrosis factor-α, C-reactive protein (CRP), and brain natriuretic peptide (BNP) were lower at 60 min post perfusion in pigs that underwent SICH as compared with the control group. On day 5 post MI/R, edema, intramyocardial hemorrhage, and microvascular obstruction were reduced in the hypothermia group. On day 42 post MI/R, the infarct size, IL-6, CRP, BNP, and matrix metalloproteinase-9 were reduced, and the ejection fraction was improved in pigs that underwent SICH.Conclusions::The SICH device safely and effectively reduced the infarct size and improved heart function in a pig model of MI/R. These beneficial effects indicate the clinical potential of SICH for treatment of myocardial reperfusion injury.
5.Treatment strategy and mechanical exploration of early lumbar spondylolysis
Hongliang GAO ; Hua LIU ; Tao ZHANG ; Xusheng LI ; Zirong HUANG ; Yizhe WANG ; Long CHEN ; Kai ZHANG ; Haitao YU ; Haoyue WU ; Songkai LI
Chinese Journal of Orthopaedic Trauma 2023;25(10):915-920
Lumbar spondylolysis is one of the common diseases of low back pain caused by spinal surgery. Its treatment options vary depending on different conditions, from early conservative ones to late surgical ones. There are still disputes over various conservative treatments, choice of surgical methods and the biomechanics of different internal fixation techniques to repair spondylolysis. Therefore, this review summarizes the clinical outcomes of previous clinical treatments of lumbar spondylolysis and the biomechanical characteristics of various techniques to find the mechanical and evidence-based clinical data that may facilitate the treatment of lumbar spondylolysis.
6.Macrophage migration inhibitory factor protects bone marrow mesenchymal stem cells from hypoxia/ischemia-induced apoptosis by regulating lncRNA MEG3.
Zhibiao BAI ; Kai HU ; Jiahuan YU ; Yizhe SHEN ; Chun CHEN
Journal of Zhejiang University. Science. B 2022;23(12):989-1001
OBJECTIVES:
This research was performed to explore the effect of macrophage migration inhibitory factor (MIF) on the apoptosis of bone marrow mesenchymal stem cells (BMSCs) in ischemia and hypoxia environments.
METHODS:
The cell viability of BMSCs incubated under hypoxia/ischemia (H/I) conditions with or without pretreatment with MIF or triglycidyl isocyanurate (TGIC) was detected using cell counting kit-8 (CCK-8) analysis. Plasmids containing long noncoding RNA (lncRNA) maternally expressed gene 3 (MEG3) or β-catenin small interfering RNA (siRNA) were used to overexpress or downregulate the corresponding gene, and the p53 signaling pathway was activated by pretreatment with TGIC. The influences of MIF, overexpression of lncRNA MEG3, activation of the p53 signaling pathway, and silencing of β-catenin on H/I-induced apoptosis of BMSCs were revealed by western blotting, flow cytometry, and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) staining.
RESULTS:
From the results of CCK-8 assay, western blotting, and flow cytometry, pretreatment with MIF significantly decreased the H/I-induced apoptosis of BMSCs. This effect was inhibited when lncRNA MEG3 was overexpressed by plasmids containing MEG3. The p53 signaling pathway was activated by TGIC, and β-catenin was silenced by siRNA. From western blot results, the expression levels of β-catenin in the nucleus and phosphorylated p53 (p-p53) were downregulated and upregulated, respectively, when the lncRNA MEG3 was overexpressed. Through flow cytometry, MIF was also shown to significantly alleviate the increased reactive oxygen species (ROS) level of BMSCs caused by H/I.
CONCLUSIONS
In summary, we conclude that MIF protected BMSCs from H/I-induced apoptosis by downregulating the lncRNA MEG3/p53 signaling pathway, activating the Wnt/β-catenin signaling pathway, and decreasing ROS levels.
Humans
;
RNA, Long Noncoding/metabolism*
;
Macrophage Migration-Inhibitory Factors/metabolism*
;
beta Catenin/metabolism*
;
Reactive Oxygen Species/metabolism*
;
Sincalide/metabolism*
;
Tumor Suppressor Protein p53/metabolism*
;
Apoptosis
;
Mesenchymal Stem Cells
;
Wnt Signaling Pathway/genetics*
;
RNA, Small Interfering/metabolism*
;
Hypoxia/metabolism*
;
Ischemia
;
Bone Marrow Cells
7.Multimodal imaging characteristics of fundus in patients with sympathetic ophthalmia
Yizhe CHENG ; Chengrui ZHANG ; Chunli CHEN ; Zhihan ZHANG ; Simeng HOU ; Xiaoyan PENG
Chinese Journal of Ocular Fundus Diseases 2022;38(5):359-365
Objective:To observe and analyze the multimodal imaging characteristics of fundus in patients with sympathetic ophthalmia (SO).Methods:A retrospective study. From October 2012 to December 2021, 28 patients (36 eyes) diagnosed SO in the Department of Ophthalmology, Beijing Tongren Hospital were inclued in the study. There were 19 males (25 eyes) and 9 females (11 eyes), with the mean age of 51.61±12.02 years. There were 8 exciting eyes and 28 sympathizing eyes. The time to onset after trauma or surgery was 46.10±107.98 months. All patients underwent examinations including vision test, color fundus photograph, optical coherence tomography (OCT), fundus fluorescence angiography (FFA), indocyanine green angiography (ICGA). Angio-OCT (OCTA) was performed on 3 eyes and fundus autofluorescence (AF) was performed on 8 eyes. The early and late phase were defined respectively as ≤2 months and >2 months. Their multimodal imaging characteristics were summarized.Results:In 8 exciting eyes, subretinal fibrosis with mutifocal retinal atrophy and pigmentation was noted in 5 eyes (62.50%, 5/8), the other 3 eyes showed sunset glow fundus (37.50%, 3/8). In 28 sympathizing eyes, in the early phase, the fundus photograph showed shallow retinal detachment with optic disc edema in 9 eyes (32.14%, 9/28); in the late phase, peripapillary yellowish-white subretinal lesions in 11 eyes (39.29%, 11/28). In the late course of the disease, there were yellow-white lesions around the optic disc (peridisc) and peripheral subretinal area in 11 eyes (39.29%, 11/28). Dalen-Fuchs nodules were found in 10 eyes (35.71%, 10/28). On OCT, multiple serous retinal detachment and irregular choroidal folds were noted in the early phase; hill-like subretinal hyperreflective elevation was noted in peripapillary area and subfovea with presence of cystic spaces in the intraretina in the late phase. FFA examination showed"pinpoint-like" strong fluorescence in the early stage, and "multi-lake-like" fluorescein accumulation and leakage in the late stage; "map-like" weak fluorescence around the disc in the early stage of the disease, dot-like strong fluorescence lesions in each quadrant of the peripheral retina, and fluorescence in the late stage of the disease course. enhanced. ICGA examination showed that the FFA strong fluorescence lesions in the middle and late stages were weak fluorescence. FAF examination, point-like strong and weak autofluorescence lesions with unclear boundaries. Nine sympathizing eyes with subretinal yellow-white lesions has vision without light-0.1 (significantly decreased vison), while 8 eyes with sunset glow fundus was 0.5-1.0 (mildly decreased vison).Conclusions:SO could not only show the semblable features of acute phases of Vogt-Koyanagi-Harada syndrome, but also the yellowish-white lesions in the peripapillary area, macula and periphery. Most of the eyes with peripapillary lesions has a significantly decreased vison, while the eyes with sunset glow fundus has a mildly decreased vison.
8.Mirror-type rehabilitation training with dynamic adjustment and assistance for shoulder joint.
Sheng CHEN ; Yizhe YAN ; Guozheng XU ; Xiang GAO ; Kangjin HUANG ; Chun TAI
Journal of Biomedical Engineering 2021;38(2):351-360
The real physical image of the affected limb, which is difficult to move in the traditional mirror training, can be realized easily by the rehabilitation robots. During this training, the affected limb is often in a passive state. However, with the gradual recovery of the movement ability, active mirror training becomes a better choice. Consequently, this paper took the self-developed shoulder joint rehabilitation robot with an adjustable structure as an experimental platform, and proposed a mirror training system completed by next four parts. First, the motion trajectory of the healthy limb was obtained by the Inertial Measurement Units (IMU). Then the variable universe fuzzy adaptive proportion differentiation (PD) control was adopted for inner loop, meanwhile, the muscle strength of the affected limb was estimated by the surface electromyography (sEMG). The compensation force for an assisted limb of outer loop was calculated. According to the experimental results, the control system can provide real-time assistance compensation according to the recovery of the affected limb, fully exert the training initiative of the affected limb, and make the affected limb achieve better rehabilitation training effect.
Electromyography
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Humans
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Movement
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Muscle Strength
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Robotics
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Shoulder Joint
;
Stroke Rehabilitation
9. Effect of pituitrin-water separation in laparoscopic removal of ovarian chocolate cyst and its effect on ovarian function
Lingling WANG ; Yizhe CHEN ; Mimi DAI ; Lingli ZHOU ; Jie MEI ; Xiaohong GE
Chinese Journal of Primary Medicine and Pharmacy 2019;26(24):2965-2968
Objective:
To investigate the effect of pituitrin-water separation on hemoglobin and ovarian function in laparoscopic ovarian chocolate cyst removal.
Methods:
From February 2018 to February 2019, 82 patients with ovarian chocolate cyst removed by laparoscopy were selected from the Second Affiliated Hospital of Wenzhou Medical University.They were randomly divided into observation group and control group according to the digital table, with 41 cases in each group.The control group underwent traditional laparoscopic tear-and-tear ovarian cyst removal, while the observation group underwent pituitrin-water separation.The changes of perioperative indicators, the decrease of hemoglobin (Hb) before and after operation, the positive rate of normal ovarian tissue on cyst wall and the number of normal follicles attached to cyst wall, the changes of serum hormone levels before and after operation were compared between the two groups.
Results:
The amount of bleeding during operation in the observation group [(58.97±8.74)mL] was less than that in the control group [(118.93±24.21)mL], and the operation time in the observation group[(57.46±8.27)min] was shorter than that in the control group [(87.38±10.19)min] , the differences were ststistically significant between the two group(
10.Modulation of Hippo signaling pathway facilitates mesenchymal stem cells to repair lung injury in murine lipopolysaccharide induced acute respiratory distress syndrome
Liang DONG ; Lang LI ; Yizhe CHEN ; Jiaojie HUI
Chinese Journal of Emergency Medicine 2019;28(7):855-862
Objectives To determine the effect of Hippo signaling pathway on lung injury repair of bone-marrow derived mesenchymal stem cells (mMSCs) in murine lipopolysaccharide (LPS) induced acute respiratory distress syndrome (ARDS).Methods C57BL/6 mouse bone marrow-derived MSC (mMSCs) cell lines with low expression of large tumor suppressor 1 (LATS 1) were constructed by lentiviral vector transfection.ARDS was modeled by intratracheally injection of 2 mg/mL lipopolysaccharide (LPS)50 μL.C57BL/6 mice were randomly(random number) divided into four groups (n=36):normal control group,ARDS group,ARDS mice transplanted with mMSCs transfected with blank lentivirus vector (MSC-shcontrol group) or sh-LATS 1 lentivirus vector (MSC-shLATS 1 group).Mice were sacrificed at 3,7,and 14 d after modeling,and lung tissue and bronchoalveolar lavage fluid (BALF) were collected.Near-infrared fluorescence imaging,immunofluorescence staining and Western blot were used to evaluate retention and differentiation of mMSCs in lung tissue.Lung tissue wet weight/body weight ratio (LWW/BW) and total protein (TP) and albumin (ALB) in BALF were determined to reflect pulmonary edema.The expression of Occludin protein in lung epithelium was tested by Western blot.The levels of interleukins (IL-1β,IL-6,and IL-10) in BALF were assessed by enzyme-linked immunosorbent assay (ELISA).Lung injury score and pulmonary fibrosis score in lung tissue were assessed.Results The retention ofmMSCs at 3,7 and 14 d in the MSC-shLATS1 group were significantly higher than those in the MSC-shcontrol group [(26.25±4.58) vs (12.13±3.75) cells/HP,(20.49±3.86) vs (9.97±2.76) cells/HP,and (13.77±3.55) vs (6.89±2.10) cells/HP.all P<0.05],so was the differentiation of mMSCs into type Ⅱ alveolar epithelial cells at 14 d [(64.12±15.29)% vs (19.64±3.71)%,P<0.05].LWW/BW and TP and ALB in BALF at 3 and 14 d in the MSC-shLATS1 group [(9.85±1.51),(6.11±0.83) (mg/g) and (5.12±0.87),(3.05±0.87) (mg/mL)and (0.44±0.18),(0.33±0.04) (mg/mL)] were higher than those in the MSC-shcontrol group [(14.88± 1.74),(8.04±l.70)(mg/g) and (8.08±1.72),(5.94±1.20) (mg/mL) and (0.71±0.21),(1.07±0.29) (mg/mL)] (all P<0.05),so was the relative expression of Occludin protein[(0.79±0.11) vs (0.49±0).19),(P<0.05)].The levels of IL-1β and IL-6(pg/mL) in BALF in the MSC-shLATS1 group [(60.11±8.58),(101.74±11.55)] was lower than those in the MSC-shcontrol group [(99.26±14.32),(145.54±13.29)] (all P<0.05),but the levels of IL-10 in BALF in the MSC-shLATS 1 group (316.65±37.88)pg/mL was higher than those in the MSC-shcontrol group (190.83±22.61)pg/mL (P<0.05).Lung injury scores at 3 and 14 d in the MSC-shLATS1 group [(7.18±1.12),(3.33±0.49)] was lower than those in the MSC-shcontrol group [(9.72±1.45),(5.11±0.86)] (all P<0.05),so was pulmonary fibrosis score at 14 d [(0.68±0.12) vs (1.47±0.18),P<0.05].Conclusion Inhibition of Hippo signaling pathway through underexpression of LATS1 could improve the therapeutic effects of mMSCs in murine LPS-induced ARDS.

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