The sealing performance is directly related to the safety,reliability and mission success rate of aerospace equipment.The sealing performance of rubber seals and the optimized design of the compression force directly affect the performance and work efficiency of the equipment.Based on the hyperelastic Mooney-Rivlin model of nonlinear materials,the mechanical properties of rubber are simulated,and a finite element model of rubber seals is established.Through simulation analysis,the effects of different cross-section dimensions and compression amounts on the sealing performance are studied and compared,and key parameters such as the contact stress distribution,maximum contact stress,and compression force.The size of the fillet affects the final deformation and the contact state.By optimizing the geometric parameters,the compression force can be reduced while ensuring the sealing performance,providing a theoretical basis for the optimized design of rubber seals.

OBJECTIVES: To explore the therapeutic mechanism of compound Centella asiatica formula (CCA) for alleviating Schistosoma japonicum (Sj)-induced liver fibrosis in mice. METHODS: The active components and targets of CCA were identified using the TCMSP database with cross-analysis of Sj-related liver fibrosis targets. A "drug-component-target-pathway-disease" network was constructed using Cytoscape 3.9.1. Functional enrichment analysis (GO/KEGG) was performed using DAVID. Molecular docking study was carried out to validate interactions between the core targets and the key compounds. For experimental validation of the results, 36 mice were divided into control group, Sj-infected model group, and CCA-treated groups. In the latter two groups, liver fibrosis was induced via abdominal infection with Sj cercariae for 8 weeks, followed by 8 weeks of daily treatment with CCA decoction or saline. Hepatic pathology of the mice was assessedwith HE and Masson staining, and hepatic expressions of collagen-I and collagen-III were detected using immunohistochemistry; serum IL-6 and TNF-α levels were determined with ELISA. Hepatic expressions of TLR4 and MyD88 proteins were analyzed with Western blotting. RESULTS: We identified a total of 107 bioactive CCA components and 791 targets, including 37 intersection targets linked to Sj-induced fibrosis. The core targets included TNF, TP53, JUN, MMP9, and CXCL8, involving the IL-17 signaling, lipid metabolism, TLR4/MyD88 axis, and cancer pathways. Molecular docking study confirmed strong binding affinity between quercetin (a primary CCA component) and TNF/TP53/JUN/MMP9. In Sj-infected mouse models, CCA treatment significantly attenuated hepatic inflammatory cell infiltration, reduced collagen-I and collagen-III deposition, improved tissue architecture, reduced serum IL-6 and TNF-α levels, and downregulated TLR4 and MyD88 expressions in the liver. CONCLUSIONS CCA mitigates Sj-induced liver fibrosis by targeting TNF, TP53, JUN, and MMP9 to modulate the TLR4/MyD88 pathway, thereby suppressing pro-inflammatory cytokine release, inhibiting hepatic stellate cell activation, reducing collagen deposition, and preventing granuloma formation in the liver.
Animals ; Toll-Like Receptor 4/metabolism* ; Mice ; Myeloid Differentiation Factor 88/metabolism* ; Schistosoma japonicum ; Liver Cirrhosis/parasitology* ; Schistosomiasis japonica ; Signal Transduction ; Molecular Docking Simulation ; Inflammation ; Centella/chemistry* ; Drugs, Chinese Herbal/pharmacology* ; Tumor Necrosis Factor-alpha/metabolism*

Objective:To evaluate the relationship between preoperative plasma trimethylamine oxide (TMAO) concentrations and postoperative delirium (POD) in elderly patients.Methods:One hundred and eighty patients, aged ≥65 yr, of American Society of Anesthesiologists Physical Status classification Ⅱ or Ⅲ, with body mass index of 17-30 kg/m 2, scheduled for elective hip replacement, were enrolled in this study. Venous blood samples were collected at 1 day before surgery, and the plasma TMAO concentrations were measured by high throughput liquid chromatography-tandem mass spectrometry. The patients were divided into 3 groups according to the concentrations of TMAO: low-concentration TMAO group (group L, ≤1.2 μmol/L), moderate-concentration TMAO group (group M, 1.3-1.9 μmol/L), and high-concentration TMAO group (group H, ≥2.0 μmol/L). All patients received superior inguinal fascia iliaca compartment block combined with intravenous general anesthesia. POD was identified by the Confusion Assessment Method-Chinese Reversion scale at 1, 2, 3 and 7 days after operation. The patients were divided into POD group and non-POD group according to whether POD occurred. Binary logistic regression analysis was used to evaluate the relationship between different plasma TMAO concentrations and POD. The receiver operating characteristic curve was used to evaluate the efficacy of plasma TMAO concentrations in predicting the occurrence of POD. Results:There were 60 cases in L group, 67 cases in M group and 53 cases in H group, and the incidence of POD was 12%, 22% and 32% in L, M and H groups, respectively. The incidence of POD was significantly higher in group H than in group L ( P<0.05). The plasma TMAO concentration was significantly higher in POD group than in non-POD group ( P<0.05). Logistic regression analysis showed that the risk of POD was 3.91 times higher in group H than in group L ( P<0.05). The area under the receiver operating characteristic curve of preoperative plasma TMAO concentrations in predicting POD was 0.754 (95% confidence interval 0.671-0.838, P<0.05). When the Youden index was 0.426, the optimal cut-off value of plasma TMAO concentrations was 1.625 μmol/L, and the specificity and sensitivity were 0.795 and 0.631, respectively. Conclusions:Elevated preoperative plasma TMAO concentration is associated with an increased risk of POD in elderly patients, and it has a good predictive value for POD.

Objective:To evaluate the effect of regional oxygen saturation (rSO 2)-guided low-dose norepinephrine on postoperative cognitive dysfunction (POCD) in elderly patients undergoing hip replacement under general anesthesia. Methods:One hundred and twenty patients of both sexes, aged 65-80 yr, with body mass index of 18-24 kg/m 2, of American Society of Anesthesiologists physical statusⅠ-Ⅲ, scheduled for hip replacement under general anesthesia, were divided into 2 groups ( n=60 each) using a random number table method: control group (group C) and low-dose norepinephrine guided by rSO 2 group (group RN). The patients in both groups received superior inguinal fascial space block combined with general anesthesia under laryngeal mask placement.In group C, the fluctuation range of mean arterial pressure (MAP) was not more than 20% of the baseline, vasoactive agents were administered according to the changes in blood pressure, rSO 2 was monitored continuously, but the change rate of rSO 2 was not used as the regulating index.In group RN, norepinephrine was infused continuously via the central vein at 0.01-0.10 μg·kg -1·min -1 after anesthesia induction, the dose was adjusted according to rSO 2, the rSO 2 change rate was maintained≤10%, the fluctuation range of mean arterial pressure was not more than 20% of the baseline, and vasoactive agents were administered when necessary.MAP, end-tidal pressure of carbon dioxide (P ETCO 2) and rSO 2 were recorded after inhalation of oxygen (T 0), at 5 min after anesthesia induction (T 1), at 30 min after skin incision (T 2), at the end of surgery (T 3) and after recovery and extubation (T 4), and the change rate of rSO 2 was calculated.The occurrence of adverse events and amount of vasoactive drugs used were recorded.The cognitive function was assessed using Montreal Scale at 1 day before surgery and 7 days after surgery, and the development of postoperative cognitive dysfunction (POCD) was calculated using Z score.The postoperative hospital stay time was recorded. Results:Compared with group C, MAP and rSO 2 were significantly increased, and the change rate of rSO 2 was decreased at T 1, 2 in group RN ( P<0.05). Compared with group C, the requirement for intraoperative vasoactive drugs was significantly decreased, the consumption of norepinephrine was increased, MoCA total score, attention and delayed recall sub-score were increased at 7 days after surgery, the incidence of POCD was decreased, and the postoperative hospital stay time was shortened in group RN ( P<0.05). Conclusion:Low-dose norepinephrine guided by rSO 2 can decrease the development of POCD in elderly patients undergoing hip replacement under general anesthesia.

Objective To observe the effect of ultrasound-guided single erector spinae plane (ESP ) block combined with patient-controlled intravenous analgesia (PCIA ) on postoperative analgesia in patients undergoing lobectomy performed via video-assisted thoracoscope. Methods Forty patients (20 males and 20 females,ASA physical status Ⅰ or Ⅱ),scheduled for e-lective video-assisted thoracoscopic lobectomy,were randomly assigned into two groups,ESP block combined with PCIA group (group EP)and PCIA only group (group P).ESP block was given to pa-tients in group EP before operation,and its effect was evaluated by testing the area of block.VAS scores were recorded at 1,6,18,24 and 48 h after operation.The frequency for compress PCIA,the volume of analgesic drugs,the consumption of flurbiprofen axetil and the side-effects were recorded as well.Results ESP block was accomplished in group EP with sensory loss from T2-T8 or T3-T7 over the entire posterolateral aspect of the hemithorax.And there were no puncture-related complications. The VAS scores both at rest and coughing in group EP were lower than those in group P (P <0.05). The compress PCA numbers,the volume of analgesic drugs and the consumption of flurbiprofen axetil were significantly less in group EP than those in group P (P <0.05).Only nausea and vomiting were observed as postoperative side effects,and there were no significant differences between the two groups.Conclusion Ultrasound-guided single erector spinae plane block combined with PCIA is a sa-fer and more effective method for the analgesia of thoracic operation than PCIA only.

BACKGROUND:Compound Chinese medicine is a kind of compound drugs with the combination of minerals, plants and animals, which play the multi-target integrated treatment effects in the treatment of bone metabolic disease through various methods.
OBJECTIVE:To research the effect of compound traditional Chinese medicine on the proliferation and bone mineral density of osteoblasts, and to explore the pharmacological effect of compound traditional Chinese medicine in the treatment of osteoporosis.
METHODS: A retrospective analysis was performed to analyze the effect of some compound traditional Chinese medicines on the proliferation and bone mineral density of osteoblasts that identified in the previous studies, in order to analyze the factors of compound traditional Chinese medicines that can promote the bone formation. The appropriate dose of the drugs that can promote cel proliferation and differentiation and improve the bone mineral density was screened out through the in vitro culture of osteoblasts, and then compared with the results of chemical medicines.
RESULTS AND CONCLUSION:Compound traditional Chinese medicines can promote the proliferation and differentiation of osteoblasts and improve the bone mineral density, and have the advantages of ful treatment and less side effect in the treatment of osteoporosis. But the effect of compound traditional Chinese medicines in improving the bone mineral density is less than the chemical drugs. The long-term and large-sample clinical studies should be performed to decrease the risk of osteoporotic fracture.