1.Finite element analysis of stress distribution of anchors at different implantation depths under different bone density conditions in rotator cuff tears
Meng WANG ; Tan LU ; Minjie LI ; Zhicheng LIU ; Xiaoyong GUO
Chinese Journal of Tissue Engineering Research 2026;30(3):561-569
BACKGROUND:Arthroscopic anchor repair has become the main treatment method for rotator cuff tears at present.Among them,the insertion status of the anchor is a key factor in the success or failure of the operation.However,currently,the impact of the insertion depth of the anchor on the stress of the bone tunnel and the anchor under different bone density conditions remains unclear.OBJECTIVE:To explore the stress distribution of the bone tunnel and the anchor when the insertion depth of the anchor varies under different bone density conditions by using three-dimensional finite element analysis technology.METHODS:The CT image data of the humerus of volunteers were collected,and the models of the humerus and the anchor were constructed by using Mimics,3-Matic,and Solidworks software.In 3-Matic,holes with distances of 0,2,4,6,and 8 mm from the surface of the humerus were respectively created at the same position of the humerus and assembled with the anchor.In Mimics,values were assigned based on the CT gray value to obtain a model with normal bone mass(T value ≥-1.0).The parameters were changed to construct models with reduced bone mass(-2.5<T value<-1.0)and osteoporosis(T value<-2.5).In each model,a 70 N pulling force was applied to the anchor along the direction tangent to the inner edge of the bone tunnel.The stress distribution and magnitude of the bone tunnel and the anchor when inserted at different depths under different bone density conditions were observed.RESULTS AND CONCLUSION:(1)When the insertion depth was the same,as the bone density decreased,the maximum equivalent stress of the anchor increased,while the maximum equivalent stress of the bone tunnel decreased.(2)When the bone density was the same,as the insertion depth of the anchor increased,the maximum equivalent stress of the anchor decreased.When the insertion depth was 4 mm,the stress of the bone tunnel was the smallest and the distribution was relatively uniform.The stress of the anchor was mainly distributed around the lower anchor hole and the proximal thread,and the stress of the bone tunnel was mainly at the part in contact with the proximal thread.The increase in the insertion depth would change the uniformity and pattern of the stress distribution,while the bone density had a relatively small impact on the stress distribution pattern.(3)It is concluded that the bone density of the humerus is crucial for the anchor repair of rotator cuff tears.It is recommended that clinicians measure the bone density of the greater tuberosity of the humerus before the operation.Excessive insertion depth of the anchor does not significantly increase its stability.Clinicians can conduct personalized preoperative assessments by using the finite element analysis method in combination with the actual situation of patients to achieve the best surgical results.
2.Finite element analysis of stress distribution of anchors at different implantation depths under different bone density conditions in rotator cuff tears
Meng WANG ; Tan LU ; Minjie LI ; Zhicheng LIU ; Xiaoyong GUO
Chinese Journal of Tissue Engineering Research 2026;30(3):561-569
BACKGROUND:Arthroscopic anchor repair has become the main treatment method for rotator cuff tears at present.Among them,the insertion status of the anchor is a key factor in the success or failure of the operation.However,currently,the impact of the insertion depth of the anchor on the stress of the bone tunnel and the anchor under different bone density conditions remains unclear.OBJECTIVE:To explore the stress distribution of the bone tunnel and the anchor when the insertion depth of the anchor varies under different bone density conditions by using three-dimensional finite element analysis technology.METHODS:The CT image data of the humerus of volunteers were collected,and the models of the humerus and the anchor were constructed by using Mimics,3-Matic,and Solidworks software.In 3-Matic,holes with distances of 0,2,4,6,and 8 mm from the surface of the humerus were respectively created at the same position of the humerus and assembled with the anchor.In Mimics,values were assigned based on the CT gray value to obtain a model with normal bone mass(T value ≥-1.0).The parameters were changed to construct models with reduced bone mass(-2.5<T value<-1.0)and osteoporosis(T value<-2.5).In each model,a 70 N pulling force was applied to the anchor along the direction tangent to the inner edge of the bone tunnel.The stress distribution and magnitude of the bone tunnel and the anchor when inserted at different depths under different bone density conditions were observed.RESULTS AND CONCLUSION:(1)When the insertion depth was the same,as the bone density decreased,the maximum equivalent stress of the anchor increased,while the maximum equivalent stress of the bone tunnel decreased.(2)When the bone density was the same,as the insertion depth of the anchor increased,the maximum equivalent stress of the anchor decreased.When the insertion depth was 4 mm,the stress of the bone tunnel was the smallest and the distribution was relatively uniform.The stress of the anchor was mainly distributed around the lower anchor hole and the proximal thread,and the stress of the bone tunnel was mainly at the part in contact with the proximal thread.The increase in the insertion depth would change the uniformity and pattern of the stress distribution,while the bone density had a relatively small impact on the stress distribution pattern.(3)It is concluded that the bone density of the humerus is crucial for the anchor repair of rotator cuff tears.It is recommended that clinicians measure the bone density of the greater tuberosity of the humerus before the operation.Excessive insertion depth of the anchor does not significantly increase its stability.Clinicians can conduct personalized preoperative assessments by using the finite element analysis method in combination with the actual situation of patients to achieve the best surgical results.
3.Preparation of spermine-pullulan-PLGA-CD3 nanoparticles and their effects on T cell proliferation and cytokine secretion
Mengyuan WANG ; Hongyang CHEN ; Yifan HE ; Xi LI ; Mengyuan ZHAO ; Xiaocong DONG ; Yichen HE ; Hongli CHEN
International Journal of Biomedical Engineering 2025;48(1):33-40
Objective:To prepare pullulan-spermine (PS)-poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) conjugated with CD3 antibody, and to investigate their effects on T cell proliferation and cytokine secretion.Methods:Purulan polysaccharide was sperminized to synthesize PS, hydrophobically modified, and then grafted with PLGA to synthesize PS-PLGA. Infrared spectroscopy and nuclear magnetic resonance hydrogen spectrum were used to characterize the structure of PS-PLGA. PS-PLGA NPs were prepared by ultrasonic dialysis method and then coupled with CD3 antibody to prepare PS-PLGA-CD3 NPs. The morphological features of PS-PLGA-CD3 NPs were observed by the transmission electron microscope. The particle sizes, Zeta potential and dispersive coefficient of the NPs were measured using the dynamic laser particle size analyzer. The amount of coupled CD3 antibody on the surface of the NPs was determined using quantitative fluorescence analysis method. The effects of 1, 10, 50, 100, and 200 μg/ml PS-PLGA-CD3 NPs on T-cell proliferation were determined using cell counting kit-8 method. The effects of 1, 10, 50, 100, 200 μg/ml PS-PLGA-CD3 NPs on secretion of interferon-γ (IFN-γ), interleukin-2 (IL-2), and tumor necrosis factor-β (TNF-β) by T cell were determined by enzyme-linked immunosorbent assay. Comparisons were made using independent sample t-test or one-factor analysis of variance. Results:Pullulan and PS showed strong absorption at 2 939 cm ?1, and PS had a weaker absorption peak at 3 384 cm ?1 than pullulan. The proton peaks of spermine appeared at chemical shifts of 1.25 to 1.50, 1.63, and 2.25 to 2.75. The characteristic peaks of PLGA appeared at chemical shifts of 1.50, 3.40, and 4.80 to 5.30. Compared to pullulan, the characteristic peaks of both PS and PLGA appeared in the corresponding intervals for PS-PLGA. The morphology of PS-PLGA-CD3 NPs with spermine substitution at 9.7% was all regular and circular, with a mean particle size of (173.3±24.5) nm, a Zeta potential of (?12.78±3.68) mV, the dispersive coefficient of 0.254±0.101, and the CD3 antibody mass fraction of (52.1±9.4) μg/mg. The differences in cell survival were statistically significant for PS-PLGA-CD3 NPs and PS-PLGA NPs, respectively, after co-incubation with T cell after 24, 48, and 72 h at concentrations of 50, 100, and 200 μg/ml, respectively (all P<0.05). The results of the three concentration comparisons after 24 h of co-incubation were [(129.8±23.1)% vs (95.5±8.9)%, (137.5±22.7)% vs (95.1±15.8)%, and (142.3±25.6)% vs (93.2±9.2)%]; and the results after 48 h were [(145.9±23.7)% vs (95.8±10.6)%, (149.3±23.5)% vs (94.9±16.3)%, and (161.2±26.9)% vs (91.5±8.3)%]; and the results after 72 h were [(147.6±20.1)% vs (95.9±17.8)%, (152.4±22.3)% vs (92.7±16.5)%, and (167.7±25.4)% vs (90.8±17.4)%]. The differences in the levels of IFN-γ, IL-2 and TNF-β were statistically significant (all P<0.05 or 0.01) at 50, 100 and 200 μg/ml concentrations for PS-PLGA-CD3 NPs and PS-PLGA NPs, respectively. For IFN-γ, the results of the comparison of the three concentrations were [(35.7±3.1) ng/ml vs (16.4±6.9) ng/ml, (67.3±5.2) ng/ml vs (19.6±2.8) ng/ml, and (79.0±4.2) ng/ml vs (19.3±2.3) ng/ml]; and for IL-2, the results were [(43.5±8.2) ng/ml vs (12.6±1.9) ng/ml, (53.5±7.8) ng/ml vs (15.8±3.3) ng/ml, and (64.0±8.2) ng/ml vs (17.4±3.8) ng/ml]; and for TNF-β, the results were [(108.4±18.9) pg/ml vs (40.8±1.3) pg/ml, (152.3±28.3) pg/ml vs (56.4±3.7) pg/ml and (185.0±33.6) pg/ml vs (81.6±10.2) pg/ml]. Conclusions:PS-PLGA-CD3 NPs are successfully prepared, which have the function of effectively promoting T cell proliferation and cytokine sectetion.
4.A real-world study on efficacy of different second-line treatment strategies following the progression of first-line immunotherapy and its combination therapies in driver gene-negative advanced non-small cell lung cancer
Luying ZHANG ; Jiaxin LIANG ; Kelei ZHAO ; Xiaohan YUAN ; Liangbo LIU ; Ping LU ; Guifang ZHANG ; Min ZHANG
Journal of International Oncology 2025;52(7):419-425
Objective:To explore the efficacy of different second-line treatment strategies in the real world after progression of first-line immunotherapy and its combination therapies in patients with driver gene-negative advanced non-small cell lung cancer (NSCLC) .Methods:A retrospective analysis was conducted on the clinical data of 93 driver gene-negative advanced NSCLC patients who received first-line immunotherapy and its combination therapies from January 1, 2018 to December 31, 2023 at the First Affiliated Hospital of Xinxiang Medical University and Xinxiang Central Hospital. Patients were categorized into immune checkpoint inhibitors (ICIs) -resistant ( n=43) and ICIs-responsive ( n=50) groups according to whether progression free survival (PFS) exceeded 6 months after first-line treatment. Patients were categorized into ICIs-treated ( n=55) and non-ICIs-treated ( n=38), anti-angiogenic-treated ( n=51) and non-anti-angiogenic-treated ( n=42) groups according to the different second-line treatment strategies after progression of first-line immunotherapy and its combination therapies. The median PFS2 (mPFS2) and median overall survival (mOS) 2 after second-line treatment of each group were compared. The Kaplan-Meier method was used for survival analysis. Results:The mPFS2 and mOS2 of 93 advanced NSCLC patients who progressed after first-line ICIs treatment were 4.9 months (95% CI: 4.1-5.7 months) and 14.7 months (95% CI: 11.2-18.2 months). The mPFS2 of patients in the first-line ICIs-responsive and ICIs-resistant groups were 6.0 and 3.8 months, respectively, with no statistically significant difference ( χ2=2.00, P=0.157), and the mOS2 were 25.3 and 11.3 months, respectively, with a statistically significant difference ( χ2=12.13, P<0.001). The mPFS2 of patients in the second-line ICIs-treated group and the non-ICIs-treated group were 5.2 and 4.6 months, respectively, with no statistically significant difference ( χ2=0.16, P=0.687). The mOS2 were 15.1 and 12.7 months, respectively, with no statistically significant difference ( χ2=0.01, P=0.930). The mPFS2 of patients in the second-line anti-angiogenic-treated and non-anti-angiogenic-treated groups were 4.5 and 6.0 months, respectively, with no statistically significant difference ( χ2=0.41, P=0.525), the mOS2 were 14.7 and 16.8 months, respectively, with no statistically significant difference ( χ2=0.01, P=0.943) . Conclusions:After progression of first-line ICIs therapy in patients with driver gene-negative advanced NSCLC, first-line ICIs-responsive patients have significantly longer OS after second-line treatment compared with ICIs-resistant patients. The efficacy of second-line therapy in patients after progression of first-line ICIs therapy does not show significant differences due to the type of treatment strategies.
5.Plasma homocysteine concentration and MTHFR C677T polymorphism are related to ischemic stroke
Yuchao ZHANG ; Mingzhang XIE ; Mengmeng ZHAO ; Xiaochun ZHOU ; Chenyan YANG ; Yanxuan LIU
Basic & Clinical Medicine 2025;45(3):331-335
Objective To investigate the correlation of plasma homocysteine(Hcy)level and the polymorphisms of its key metabolic enzymes methylenetetrahy-drofolate reductase(MTHFR)gene with ischemic stroke(IS).Methods A total of 310 patients with IS were enrolled as the case group and 330 healthy subjects during the same period were selected as the control group.Plasma Hcy concentration was detected by enzyme cycling method,and the real-time fluorescent quantitative PCR(RT-qPCR)was used to detecte the genotypes of MTHFR C677T.Results The frequencies of TT genotype(36.13%),CT genotype(10.00%)and T allele(28.06%)of MTHFR gene C677T locus in stroke patients were significantly higher than that in control group(P<0.05).The frequency of the TT genotype was significantly higher in IS group compared to control group,indicating a recessive mode of inheritance(P<0.05);In the dominant mode of inheritance,the frequency of CT+TT genotype in IS group was also significantly higher than that in control group(P<0.05);The plasma Hay concentration of MTHFR C677T genotype TT,CT and CC patients was statistically different(P<0.05),which were(20.91±6.78)μmol/L(17.20±5.39)μmol/L,(14.35±4.32)μmol/L,respectively;The area under the ROC curve(AUC)of plas-ma total Hcy level was 0.610(95%CI:0.566~0.653,P<0.001).It indicated that it might play an impor-tant role in predicting the risk of suffering from IS.Multivariate Logistic regression analysis showed that plasma Hcy level and MTHFR C677T gene polymorphism were important risk factors of IS.Conclusions Elevated plasma Hcy level is associated with IS,and the synergistic effect of elevated Hcy level and MTHFR C677T gene mutation may increase the risk of IS.
6.Role of macrophage extracellular traps in inflammatory diseases
Qianqian WU ; Kaiting MA ; Lingfei CAO ; Xiaoping WANG
Basic & Clinical Medicine 2025;45(10):1368-1371
Macrophage extracellular traps(METs)are extracellular fibrous web-like structures produced by macro-phages.Under physiological conditions,METs capture and kill microorganisms by releasing high concentrations of granular proteins,serving as an innate immune defense mechanism and playing a vital protective role in resisting the progression of inflammatory diseases.Excessive release of METs can also exacerbate the inflammatory response and cause further tissue damage.
7.Association of MTHFR C677T gene polymorphism with serum Hcy level and subtypes of ischemic stroke
Yuchao ZHANG ; Mingzhang XIE ; Xiaochun ZHOU ; Mengmeng ZHAO ; Chenyan YANG ; Yanxuan LIU
Basic & Clinical Medicine 2025;45(12):1614-1618
Objective To investigate the relationship between methylenetetra-hydrofolatereductase(MTHFR)gene polymorphism and serum homocysteine(Hcy)level and subtypes of ischemic stroke(IS).Methods The study was conducted according to the matched principle of case-control design,310 patients with IS and 330 healthy people during the same period were selected as the case group and the control group.Recycling enzyme method and the real-time fluorescent quantitative PCR(RT-qPCR)method were used to detect the level of serum Hcy and the genotypes of MTHFR C677T,respectively.Results There was a significantly difference in MTHFR C677T genotype and allele frequency between the case and control groups(P<0.05).The correlation analysis with different subtypes indicated that the frequencies of CT genotype(38.02%),TT genotype(10.74%),and T allele(29.75%)were significantly different in the LAA group(OR=1.662,95%CI:1.058-2.608,P<0.05;OR=2.373,95%CI:1.110-5.073,P<0.05;OR=1.663,95%CI:1.190-2.323,P<0.05);The frequencies of TT genotype(10.53%)and T allele(27.30%)in SAO group were also significantly different(OR=2.130,95%CI:1.046-4.336,P<0.05;OR=1.474,95%CI:1.075-2.021,P<0.05).Further analysis of serum Hcy level showed that LAA group(19.55±5.61)μmol/L and SAO group(16.37±5.20)μmol/L were significantly higher than the control group(14.46±4.61)μmol/L(P<0.001);Among the patients of both subtypes the serum Hcy levels in those with CT genotypes and TT genotypes were significantly higher than those in patients of CC genotypes(P<0.001).Conclusions The gene polymorphism of MTHFR C677T has a significant effect on Hcy level in pa-tients with LAA and SAO stroke.
8.Therapeutic effect of remimazolam on cerebral ischemia-reperfusion injury rats by regulating the AMP-activated protein kinase/NOD-like receptor protein 3 signaling pathway
Teng FAN ; Xiao-Fang LI ; Dan SHEN ; Hong-Wei ZHANG ; Xiu-Qin YUE
Acta Anatomica Sinica 2025;56(4):431-437
Objective To investigate the effects of remimazolam(REM)on cerebral ischemia-reperfusion injury(CIRI)rats and the AMP-activated protein kinase(AMPK)/NOD-like receptor protein 3(NLRP3)signaling pathway.Methods One hundred rats were selected to construct the CIRI rat model(Mod)and stochastically separated into a Mod group,low,medium,and high dose remifentanil groups(REM-L,REM-M,REM-H),and high dose remifentanil+pathway inhibitor Compound C group(REM-H+Compound C),with 20 rats in each group.Another 20 healthy rats were included as the control(Ctrl)group.All rats were subjected to neurobehavioral scoring.The water content,infarct area,and oxidative stress indicators of brain tissue were detected.The morphology and apoptosis of brain tissue were observed by HE and TUNEL staining.Western blotting was applied to detect protein expression related to the AMPK/NLRP3 signaling pathway.Results Compared with the Mod group,with the increase of REM dose,the movement disorders in rats were alleviated,the overall structure of brain tissue gradually recovered,pathological damage was reduced,the area of cerebral infarction,brain water content,and apoptosis rate of brain tissue cells decreased,reactive oxygen species(ROS)level,malondialdehyde(MDA)content,and NLRP3 and Caspase-1 protein expression levels decreased,superoxide dismutase the(SOD)content and AMPK protein expression level increased(P<0.05).Compared with the REM-H group,the REM-H+Compound C group showed aggravated motor disorders,and more severe pathological damage to brain tissue,the area of cerebral infarction,cerebral water content and apoptosis rate of brain tissue cells increased,the ROS level,MDA content and the protein expression of NLRP3 and Caspase-1 increased,while the content of SOD and the protein expression decreased(P<0.05).Conclusion Remimazolam can enhance the antioxidant function of the body,reduce brain cell apoptosis,alleviate brain tissue injury,and thus have a certain protective effect on ischemia-reperfusion brain injury in rats,the mechanism of which may be related to the activation of the AMPK/NLRP3 signaling pathway.
9.The factors influencing the prognosis of patients with symptomatic severe intracranial artery stenosis after interventional therapy and the construction of nomogram prediction model
Jianjiang FAN ; Chaogang WANG ; Yuanjie XU ; Xinhui CAO ; Xiaoman ZHANG
Journal of Interventional Radiology 2025;34(6):631-638
Objective To explore the factors affecting the prognosis of patients with symptomatic severe intracranial artery stenosis after interventional therapy,and to construct a nomogram prediction model accordingly.Methods The clinical data of 121 patients with symptomatic severe intracranial artery stenosis,who received interventional treatment at the First People's Hospital of Zhengzhou from June 1,2021 to October 31,2024,were retrospectively analyzed.The general data,characteristics of vascular lesions,treatment-related factors and prognosis of patients were collected.According to the modified Rankin scale(mRS)score,the patients were divided into good prognosis group(mRS score ≤2 points)and poor prognosis group(mRS score>2 points).The clinical data were compared between the two groups.Multivariate logistic regression analysis was used to identify and determine independent factors affecting patient's outcomes,to construct a nomogram prediction model and to validate this model.Results Among the 121 patients,31(25.61%)had poor prognosis and 90(74.38%)had good prognosis.The postoperative 3-month mRS score was lower than preoperative mRS score value(P>0.05).There were significant differences in hypertension history,stenosis site,stenosis degree,collateral circulation state,interventional therapeutic mode,cholesterol level,platelet count,lesion length and preoperative NIHSS score(P<0.05)between the poor prognosis group and the good prognosis group.Multivariate analysis showed that hypertension history,stenosis degree,collateral circulation status,cholesterol level,platelet count,lesion's length and preoperative NIHSS score were the independent influencing factors for the prognosis of patients with symptomatic severe intracranial artery stenosis.The predicted AUC of the nomogram model was 0.931(95% CI=0.873-0.989),and the calibration curve showed that the predicted value was in good agreement with the actual value.Conclusion Hypertension history,stenosis degree,collateral circulation status,cholesterol level,platelet count,lesion length and preoperative NIHSS score are the important influencing factors for the prognosis of patients with symptomatic severe intracranial artery stenosis.The nomogram prediction model constructed in this study shows a high accuracy in predicting the prognosis of patients,and it can provide important reference for clinical decision-making.
10.Value of serum absent in melanoma 2 expression level in predicting occurrence of early neurological deterioration after alteplase intravenous thrombolysis in patients with acute cerebral infarction
Fan WANG ; Xiangyang WANG ; Jianhua ZHAO
Journal of Clinical Medicine in Practice 2025;29(1):13-17,22
Objective To investigate the correlation between the expression level of absent in melanoma 2(AIM2)in serum and the severity of acute cerebral infarction(ACI),and to evaluate the value of AIM2 in predicting early neurological deterioration(END)after intravenous thrombolysis with alteplase in ACI patients.Methods A total of 150 ACI patients were enrolled in ACI group,and an-other 30 healthy individuals physical examination were selected as control group.ACI patients were further divided into mild,moderate and severe groups according to the National Institutes of Health Stroke Scale(NIHSS)score at admission,and they were also divided into END and non-END groups based on the occurrence of END after intravenous thrombolysis.Clinical materials of ACI patients were collected;the expression level of serum AIM2 was measured by enzyme-linked immunosorbent assay(ELISA);the Logistic regression analysis was performed to identify the factors influencing END after intravenous thrombolysis in ACI patients;the receiver operating characteristic(ROC)curve was plot-ted to analyze the clinical performance of serum AIM2 expression level in predicting END after intravenous thrombolysis in ACI patients.Results The serum AIM2 expression level in the ACI group and the control group was(58.29±5.97)and(36.81±3.03)ng/mL respectively,with a significant be-tween-group difference(t=43.23,P<0.05).The serum AIM2 expression level gradually in-creased in the mild,moderate and severe groups,with significant differences between each pair of groups(P<0.01).The serum AIM2 expression level in ACI patients was positively correlated with the NIHSS score(r=0.941,P<0.01).The NIHSS score,time from admission to thrombolysis,low-density lipoprotein cholesterol(LDL-C),C-reactive protein,and AIM2 level in the END group were significantly higher or longer than those in the non-END group(P<0.05).The results of mul-tivariate Logistic regression analysis showed that NIHSS score(OR=3.871,P<0.001),time from admission to thrombolysis(OR=2.885,P=0.002),LDL-C(OR=3.118,P<0.001)and AIM2(OR=3.761,P<0.001)were influencing factors for END after intravenous thrombolysis in ACI patients.ROC curve showed that the area under the curve(AUC)for predicting END after in-travenous thrombolysis based on the serum AIM2 expression level at admission in ACI patients was 0.911;when the cut-off value of AIM2 was 66.56 ng/mL,the diagnostic sensitivity and specificity were 91.23%and 90.15%,respectively.Conclusion The expression level of serum AIM2 is sig-nificantly increased in ACI patients,and AIM2 expression level has certain advantages in predicting END after intravenous thrombolysis in ACI patients.

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