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OBJECTIVE@#To establish finite element models of different preserved angles of osteonecrosis of the femoral head (ONFH) for the biomechanical analysis, and to provide mechanical evidence for predicting the risk of ONFH collapse with anterior preserved angle (APA) and lateral preserved angle (LPA).@*METHODS@#A healthy adult was selected as the study object, and the CT data of the left femoral head was acquired and imported into Mimics 21.0 software to reconstruct a complete proximal femur model and construct 3 models of necrotic area with equal volume and different morphology, all models were imported into Solidworks 2022 software to construct 21 finite element models of ONFH with LPA of 45°, 50°, 55°, 60°, 65°, 70°, and 75° when APA was 45°, respectively, and 21 finite element models of ONFH with APA of 45°, 50°, 55°, 60°, 65°, 70°, 75° when LPA was 45°, respectively. According to the physiological load condition of the femoral head, the distal femur was completely fixed, and a force with an angle of 25°, downward direction, and a magnitude of 3.5 times the subject's body mass was applied to the weight-bearing area of the femoral head surface. The maximum Von Mises stress of the surface of the femoral head and the necrotic area and the maximum displacement of the weight-bearing area of the femoral head were calculated and observed by Abaqus 2021 software.@*RESULTS@#The finite element models of ONFH were basically consistent with biomechanics of ONFH. Under the same loading condition, there was stress concentration around the necrotic area in the 42 ONFH models with different preserved angles composed of 3 necrotic areas with equal volume and different morphology. When APA was 60°, the maximum Von Mises stress of the surface of the femoral head and the necrotic area and the maximum displacement of the weight-bearing area of the femoral head of the ONFH models with LPA<60° were significantly higher than those of the models with LPA≥60° ( P<0.05); there was no significant difference in each index among the ONFH models with LPA≥60° ( P>0.05). When LPA was 60°, each index of the ONFH models with APA<60° were significantly higher than those of the models with APA≥60° ( P<0.05); there was no significant difference in each index among the ONFH models with APA≥60° ( P>0.05).@*CONCLUSION@#From the perspective of biomechanics, when a preserved angle of ONFH is less than its critical value, the stress concentration phenomenon in the femoral head is more pronounced, suggesting that the necrotic femoral head may have a higher risk of collapse in this state.
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Adulto , Humanos , Cabeça do Fêmur/cirurgia , Análise de Elementos Finitos , Estresse Mecânico , Fêmur/diagnóstico por imagem , Necrose da Cabeça do Fêmur/cirurgiaRESUMO
Objective To investigate the effects of leptin on Treg cells and the possible mecha-nism. Methods Leptin-deficient ( ob/ob) mice and homologous wild-type mice were used in this study. The percentages of Treg cells in spleen tissues and peripheral blood samples were measured by flow cytometry ( FCM) . Differences in Treg cell functionality were compared between the two groups. Splenic CD4+T cells, separated from the ob/ob mice and the wild-type mice by magnetic beads, were respectively cultured with leptin and anti-leptin neutralization antibody to evaluate the effects of leptin on Treg cells. Quantitative real-time PCR was performed to analyze the expression of Treg cell-related cytokines at transcriptional level. The levels of IL-10 and TGF-β in the supernatants of CD4+T cell culture were measured with Luminex technolo-gy. Results Compared with the wild-type mice, the ob/ob mice showed higher percentages of Treg cells in both peripheral blood samples and spleen tissues [(11. 56 ± 0. 72)％ vs (5. 47 ± 0. 81)％, (10. 16 ± 0.93)％ vs (6.29±0. 69)％]. Treg cells isolated from the ob/ob mice had stronger immunosuppressive effects on the proliferation of effector T ( Teff) cells and the secretion of TNF-α and IFN-γ than those from the wild-type mice [TNF-α:(1. 6±0. 2)％ vs (2. 4±0. 5)％, IFN-γ:(4. 3±0. 3)％ vs (7. 2±1. 2)％]. The percentages of Treg cells were decreased from (12. 2±1. 8)％ to (7. 6±0. 9)％ upon the in vitro treat-ment of CD4+ T cells from the ob/ob mice with leptin and the immunosuppressive effects of Treg cells were also weakened. However, the percentages of Treg cells were increased from (7. 8±0. 85)％ to (13. 1± 1. 5)％ upon the in vitro treatment of CD4+T cells from the wild-type mice with anti-leptin antibody and the immunosuppressive effects of Treg cells were improved as well. Moreover, the expression of Foxp3, IL-10 and TGF-β at transcriptional level and the levels of IL-10 and TGF-β in the ob/ob group were higher than those in the wild-type group. Conclusions Leptin deficiency significantly promoted the generation of Treg cells in mice and resulted in an increased expression of Foxp3, IL-10 and TGF-βat mRNA level and elevat-ed levels of IL-10 and TGF-β. The treatment of CD4+T cells with leptin might inhibit the generation of Treg cells through down-regulating the transcription of Foxp3, IL-10 and TGF-β.
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Objective@#To investigate the impact of symptom onset to first medical contact (SO-to-FMC)time on the prognosis of patients with acute ST-segment elevation myocardial infarction(STEMI).@*Methods@#The clinical data of 341 consecutive STEMI patients, who were hospitalized to our hospital and received primary percutaneous coronary intervention(PCI) from August 2011 to April 2016, were retrospectively analyzed. The patients were divided into ≤90 min group (201 cases) and >90 min group (140 cases) according to the SO-to-FMC time. The treatment time, mortality and incidence of major adverse cardiac and cerebro-vascular events(MACCE) were analyzed. The risk factor of 1-year mortality after PCI and 1-year incidence of MACCE during the post-discharge follow-up period were analyzed by binary logistic regression analysis. The predictor of 4.5-year mortality after PCI was analyzed by multivariate Cox regression analysis. Methods The door to balloon time (104(88, 125) min vs. 111(92, 144)min, P=0.023), first medical contact to balloon time(146(119, 197) min vs. 177(125, 237)min, P=0.005), and symptom onset-to-balloon time(200(170, 257) min vs. 338(270, 474)min, P<0.001)were all significantly shorter in the ≤90 min group than in>90 min group. The 30-day mortality (2.99% (6/201) vs. 7.86%(11/140), P=0.042), 1-year mortality (2.89 (5/173) vs. 9.57(11/115), P=0.015), 1-year incidence of MACCE during the post-discharge follow-up period(1.16%(2/173) vs. 6.96%(8/115), P=0.021), and 4.5-year cumulative mortality(3.00% vs. 11.20%, P=0.007) after PCI were significantly lower in the ≤90 min group than in the >90 min group. Moreover, the 4.5-year incidence with free of MACCE (97.20% vs. 88.80%, P=0.025) during the post-discharge follow-up period was significantly higher in the ≤90 min group than in the >90 min group. In-hospital mortality was similar between the two groups (2.49%(5/201) vs. 6.43%(9/140), P=0.071).@*Results@#The door to balloon time (104(88, 125) min vs. 111(92, 144)min, P=0.023) , first medical contact to balloon time(146(119, 197) min vs. 177(125, 237)min, P=0.005), and symptom onset-to-balloon time(200(170, 257) min vs. 338(270, 474)min, P<0.001) were all significantly shorter in the ≤90 min group than in >90 min group. The 30-day mortality(2.99% (6/201) vs. 7.86%(11/140), P=0.042), 1-year mortality (2.89(5/173) vs. 9.57(11/115), P=0.015), 1-year incidence of MACCE during the post-discharge follow-up period (1.16%(2/173) vs. 6.96%(8/115), P=0.021), and 4.5-year cumulative mortality (3.00% vs. 11.20%, P=0.007) after PCI were significantly lower in the ≤90 min group than in the >90 min group. Moreover, the 4.5-year incidence with free of MACCE (97.20% vs. 88.80%, P=0.025) during the post-discharge follow-up period was significantly higher in the ≤90 min group than in the >90 min group. In-hospital mortality was similar between the two groups (2.49%(5/201) vs. 6.43%(9/140), P=0.071). Results of binary logistic regression analysis showed that the SO-to-FMC time >90 min was the risk factor of 1-year mortality(OR=2.90, 95%CI 1.22-6.92, P=0.016) and 1-year incidence of MACCE (OR=5.19, 95%CI 1.21-22.20, P=0.026) during the post-discharge follow-up period. Multivariate Cox regression analysis demonstrated that the SO-to-FMC time >90 min was the risk factor of 4.5-year mortality after PCI in patients with STEMI (HR=2.88, 95%CI 1.10-7.53, P=0.031).@*Conclusion@#Shorting the SO-to-FMC time can significantly reduce the treatment time of STEMI patients, short and long-term mortalities and the incidence of MACCE, and improve the prognosis of patients with STEMI.
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Objective To examine the influence of gender difference on the reperfusion delay in patients with ST-elevation myocardial infarction (STEMI).Methods A total of consecutive 325 patients with STEMI were analyzed admitted in the 306 Hospital of PLA from Jan.2011 to Dec.2015.Patients were divided into two groups:male group (n=268) and female group (n=57).The clinical data and the time intervals including symptom onset to first medical contact (So-to-FMC),transfer delay (FMC-to-D),FMC to balloon dilatation (FMC-to-B),activation delay and door to balloon (D-to-B) time were compared between different gender groups,and the prognosis was observed.Results The overall median of pre-hospital delay was 125 minutes.The median of prehospital delay time (male 119.5min vs.female 160.0min) and So-to-FMC time (male 69.5min vs.female 100.0min) were longer in female than in male patients,but no statistical difference existed (P＞0.05) between the two groups in pre-hospital delay,So-to-FMC,FMC-to-B,D-to-B and total ischemia time.Compared with male patients,female patients were more likely to have additional comorbidities,such as hypertension and diabetes mellitus,and lower rate of smoking (P＜0.05).However,the incidence of major adverse cardiac and cerebrovascular events (MACCE) showed no significant difference between female and male patients at 30-day (male 5.22％ vs.female 5.26％) and I-year (male 10.82％ vs.female 8.77％) follow-up (P＞0.05).Conclusion The influence of gender on reperfusion delay is gradually weakening.
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Objective To investigate the relationship between ischemic time and thrombus types in patients with ST-segment elevation myocardial infarction (STEMI).Methods Eighty-two STEMI patients undergone emergency percutaneous coronary intervention (PCI) and coronary thrombus aspiration (CTA) from Sep.2012 to Apr.2016 were included and divided into 3 groups according to the ischemic time:≤4 hours (n=36),4-7 hours (n=30) and ＞7 hours (n=16).Visible aspirated thrombi were collected and separated into erythrocyte-rich type,platelet/fibrin-rich type and combined type thrombi by HE dying.The percentage difference of the 3 types thrombi was compared among the 3 groups.Results The percentage of platelet/fibrinrich type,erythrocyte-rich type and combined type thrombi in the 3 groups were as follows:in ≤4h group:61.1％(22/36),8.3％(3/36) and 30.6％(11/36),P=0.019;in 4-7h group:23.3％(7/30),10.0％(3/30) and 66.7％(20/30),P=0.012;and in ＞7h group:43.8％(7/16),12.5％(2/16) and 43.8％(7/16),P=0.913.For platelet/fibrin-rich type thrombi,the percentages in 3 periods were 61.1％(22/36),19.4％(7/36) and 19.4％(7/36),P=0.009;For combined type thrombi,the percentages in 3 periods were 28.9％(11/38),52.6％(20/38) and 18.4％(7/38),P=0.013;For erythrocyte-rich type thrombi,the percentages in 3 periods were 37.5％(3/8),37.5％(3/8) and 25.0％(2/8),P=0.895.Conclusions The types of intracoronary aspirated thrombi differ from various periods.Ischemia time may be an important predicted factor.
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Objective To investigate the effects of leptin on Th17 cells and the possible mechanism. Methods The leptin-deficient ( ob/ob) mice and their homologous wild-type mice were used in the study.The percentages of Th17 cells in peripheral blood samples, spleen tissues and lymph nodes were measured by flow cytometry ( FCM) analysis.The splenic CD4+T cells, separated from the ob/ob mice and the wild-type mice by using magnetic beads,were respectively cultured with leptin at various concentrations and with anti-leptin neu-tralization antibody to evaluate the effects of leptin on Th17 cells.The quantitative real-time PCR was performed to analyze Th17 cell-related cytokines at transcriptional levels.The levels of IL-6 and IL-17A in the supernatants of CD4+T cell culture were measured with Luminex technology.Results Compared with the wild-type mice, the ob/ob mice showed lower percentages of Th17 cells in both peripheral blood samples and spleen tissues (0.49%±0.03%vs 1.29%±0.1%, 1.56%±0.22%vs 2.47%±0.11%).There was a decrease in the percentages of Th17 cells upon the in vitro treatment of CD4+T cells from wild-type mice with anti-leptin antibody.The per-centages of Th17 cells were increased in a dose-dependent manner upon the in vitro treatment of CD4+T cells from ob/ob mice with leptin.Moreover, the levels of IL-17A and IL-6 and the transcriptional levels of RORγt, IL-17A and IL-6 in leptin deficiency group were lower than those of wild-type group, but were increased upon the treatment with leptin.No significant difference with the transcriptional levels of TGF-βand IL-23 was ob-served between the two groups with and without intervention.Conclusion Leptin deficiency seriously hampered the generation of Th17 cells in mice and resulted in a decreased expression of RORγt, IL-17A and IL-6 at mRNA level.The treatment of CD4 T cells with leptin might promote the generation of Th17 cells through up-regulating the transcription of RORγt and IL-6.
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<p><b>OBJECTIVE</b>To detect the expression levels of co-inhibitory molecules, including CTLA-4, LAG-3, PD-1 and CD39, on CD4⁺ T cells in peripheral blood or tumor tissues from NSCLC patients and to investigate their potential internal relationships with the progression of NSCLC.</p><p><b>METHODS</b>Eighty-eight patients including 53 NSCLC, 17 disease control cases and 18 healthy controls were studied. All the peripheral blood and 13 cases of tumor and tumor-adjacent tissues from surgically treated NSCLC patients were obtained. The expression levels of co-inhibitory molecules CTLA-4, LAG-3, PD-1 and CD39 were assayed by flow cytometry (FCM).</p><p><b>RESULTS</b>The ratios of CD4⁺ CTLA-4⁺ T cells, CD4⁺ LAG-3⁺ T cells, CD4⁺ PD-1⁺ T cells and CD4⁺ CD39⁺ T cells in the peripheral blood of NSCLC patients were (2.49 ± 2.43)%, (2.47 ± 3.50)%, (12.94 ± 5.96)% and (6.78 ± 5.21)%, respectively, the ratio of CD4⁺ CTLA-4⁺ T cells was significantly higher in the peripheral blood of NSCLC patients than that in the disease controls and healthy controls (P < 0.05) . The ratio of CD4(+)PD-1⁺ T cells was also highly raised in the peripheral blood of NSCLC patients than that in the healthy controls (P < 0.05). Further stratified analysis indicated that the ratio of CD4⁺ PD-1⁺ T cells was (13.21 ± 5.96)% in NSCLC patients entering stages III and IV, also significantly increased as compared with that of (11.06 ± 3.42)% in the patients undergoing stages I and II (P < 0.05). More CD4⁺ CTLA-4⁺ T cells, CD4⁺ LAG-3⁺ T cells and CD4⁺ PD-1⁺ T cells were verified in the cancer tissues (5.07 ± 2.11)%, (7.86 ± 3.24)% and (40.20 ± 18.84)%, respectively, than those in their matched peripheral blood (3.13 ± 1.01)%, (2.65 ± 1.48)% and (15.79 ± 5.69)%, (P < 0.05 for all), and especially, CD4⁺ CTLA-4⁺ T cells and CD4⁺ PD-1⁺ T cells were also highly increased than those in matched cancer-adjacent tissues (P < 0.05 for all).</p><p><b>CONCLUSIONS</b>The increased expression levels of co-inhibitory molecules CTLA-4, LAG-3 and PD-1 on CD4⁺ T cells in peripheral blood and tumor tissues may be one of the mechanisms related to immune escape of tumor cells, acceleration of disease progression and poor prognosis in NSCLC patients.</p>
