Study on Creep-Fatigue Mechanical Behavior and Life Prediction of Ti2AlNb-Based Alloy

Low-cycle fatigue, creep and creep-fatigue tests of Ti₂AlNb-based alloy were carried out at 550 °C. Compared with low-cycle fatigue, a creep-fatigue hysteresis loop has larger area and smaller average stress. The introduction of creep damage will greatly reduce the cycle life, and change the fatigue crack initiation point and failure mechanism. Based on the linear damage accumulation rule, the fatigue damage and creep damage were described by the life fraction method and the time fraction method, respectively, and the creep-fatigue life of the Ti₂AlNb-based alloy is predicted within an error band of ±2 times.     

Decreased APOC1 expression inhibited cancer progression and was associated with better prognosis and immune microenvironment in esophageal cancer

Several studies have demonstrated the involvement of apolipoprotein C1 (APOC1) in multiple cancers. However, the role of APOC1 in esophageal cancer (ESCA) has not been elucidated. Hence, we examined the expression of APOC1 in ESCA tissues acquired from The Cancer Genome Atlas (TCGA) database and clinical samples from our hospital. An investigation of the association of APOC1 with the clinicopathological characteristics, prognosis, and diagnosis of ESCA was carried out on the basis of survival, receiver operating characteristics, and correlation analyses. Gene ontology, KEGG analysis, and protein-protein interaction network showed that co-expressed APOC1 genes were involved in the functions, mechanisms, and action network. The effects of APOC1 expression on ESCA cells were explored using CCK-8, migration and invasion assays. The relationship between APOC1 expression and ESCA immune-infiltrating cells and cell markers were examined using correlation analysis. We found that APOC1 was overexpressed in TCGA ESCA tissues and the same was validated in clinical ESCA tissues, with the area under the curve for APOC1 being 0.887. Overexpression of APOC1 was associated with short overall survival, disease-specific survival, progression-free interval, T stage, pathological stage, body mass index, and histological grade. Inhibition of APOC1 expression significantly reduced the proliferation, migration, and invasion of ESCA cells. Furthermore, APOC1 expression positively correlated with the ESTIMATE, immune, and stromal scores in ESCA. Overexpression of APOC1 correlated with the tumor purity, B cells, T helper cells, natural killer cells, cytotoxic cells, and other immune cells. Moreover, APOC1 was involved in ESCA progression via T cell receptor, B cell receptor, and other immune signaling pathways. Thus, APOC1 overexpression is expected to be a biomarker for dismal prognosis and diagnosis of ESCA. Inhibition of APOC1 expression significantly reduced the proliferation, migration, and invasion of ESCA cells. Overexpression of APOC1 was associated with the immune microenvironment in ESCA. Thus, APOC1 may be an efficient biomarker for proper prognosis and diagnosis of ESCA.     

Intratumoral PD-1+CD8+ T cells associate poor clinical outcomes and adjuvant chemotherapeutic benefit in gastric cancer

Background Although PD-1 has been reported to be a marker of T-cell exhaustion in several malignancies, the biological role of PD-1⁺CD8⁺ T cells in gastric cancer (GC) remains unclear. Herein, we aimed to investigate the role of PD-1⁺CD8⁺ T cells in the tumour microenvironment and its clinical significance in GC.Designs This study included 441 tumour microarray specimens and 60 Flow cytometry specimens of GC patients from Zhongshan Hospital, and 250 GC patients from the Asian Cancer Research Group.Results Here, we demonstrated that PD-1⁺CD8⁺ T cells functioned as an independent adverse prognosticator in GC. In addition, an abundance of intratumoral PD-1⁺CD8⁺ T cells indicated worse chemotherapeutic responsiveness to fluorouracil in Stage III GC patients. Mechanistically, PD-1⁺CD8⁺ T cell high infiltration indicated an exhausted phenotype of global CD8⁺ T cells in GC tissues, which was characterised by elevated immune checkpoint expression including CTLA-4 and TIM-3, whereas decreased expression of perforin. Furthermore, PD-1⁺CD8⁺ T cell high-infiltration patients with Stage III GC held elevated activity of several therapeutic signal pathways.Conclusions Our study highlighted that PD-1⁺CD8⁺ T cell abundance predicts inferior prognosis in GC, and may serve as a novel predictive biomarker to guide therapeutic option.Subject terms: Gastric cancer, Cancer microenvironment, Tumour immunology     

不同龄段肾上腺嗜铬细胞瘤患者手术前后血压与尿杏仁酸的变化及其临床意义

目的对比不同龄段肾上腺嗜铬细胞瘤(APC)患者手术前后血压与尿杏仁酸的变化方法回顾性分析48例肾上腺嗜铬细胞瘤患者的临床、病灶直径、病程、血压与24 h尿香草基杏仁酸变化。结果两组均以女性偏多,但两组的性别差异无统计学意义;两组均以左侧偏多,但分布同样无统计学差异。老年组病灶直径明显大于中青年组（P=0.003）,且老年组病程显著长于中青年组（P=0.026）。治疗前,中青年组收缩压、舒张压及尿杏仁酸均显著低于老年组。术后,两组收缩压、舒张压及尿杏仁酸均较自身术前显著降低,且均以中青年组显著低于老年组。结论直径偏大、病程较长是老年APC的重要特征;手术可显著降低APC患者血压水平及尿杏仁酸的含量。     

基于反观面“钟摆式”吻合法的小鼠左肺原位移植改良模型（附视频）

目的  本研究从多角度对小鼠左肺原位移植模型进行改进,旨在建立一种更简易、快速和稳定的小鼠肺移植研究模型。方法  基于本团队前期大鼠左肺原位肺移植改良模型,本研究对小鼠左肺原位移植的气管插管、套管制备和受体吻合程序等均进行了不同程度的改进。由1名具有显微外科经验的操作者连续进行40例小鼠左肺原位移植手术。其中,受体肺门结构的游离在肺门钳夹平面的反观面视野下进行,并采用“钟摆式”吻合法依次对肺门三支（左主支气管、肺动脉、肺静脉）逐一吻合。详细记录各移植程序的操作时间。于术后2周处死受体,记录术后并发症的发生情况。结果  40例小鼠肺移植手术均成功完成,术中无支气管和血管撕裂、扭曲,吻合处无渗血。心肺整体获取时间为（10.7±1.5）min,套管制备时间为（16.2±1.5）min,冷缺血时间为（25.1±2.4）min,热缺血时间为（19.4±1.6）min,总手术时间为（57.2±2.9）min。在术后6~14 d的随访过程中,1只受体小鼠死于胸腔积液,考虑为感染所致;其余受体小鼠随访期间均未出现气胸、血栓和肺不张等现象。结论  本研究基于反观面“钟摆式”吻合法的小鼠左肺原位移植改良模型具有操作时间短、成功率高和并发症少等优点,有望成为可供选择的肺移植术后病理变化的研究模型,值得进一步推广。     

氢分子及其制品对肺移植保护作用的研究进展

肺移植术后缺血-再灌注损伤是导致原发性移植物功能障碍的主要原因,进而会降低肺移植受者的移植肺功能和总体生存率。氢分子作为一种生理调节性分子,具有抗炎、改善氧化应激、减轻直接细胞损伤和缓解上皮细胞水肿等作用。近年来,越来越多的研究证明氢分子及其制品（主要是氢气和富氢溶液）可以显著改善肺移植术后缺血-再灌注损伤等并发症。本文就氢分子及其制品在肺移植中的保护作用及具体机制进行回顾总结,旨在为氢分子及其制品作为一种新的肺移植相关并发症治疗手段提供理论依据,进而改善肺移植受者的总体预后及生活质量。     

氨甲环酸在开胸手术中的应用

目的评价氨甲环酸在开胸手术中的止血作用和对开胸手术围术期凝血纤溶功能的影响。方法选择因罹患肺或食管肿瘤的开胸手术患者40例,随机分为两组:氨甲环酸组(A组,n=20)在麻醉诱导后切皮前静脉滴注10mg/kg氨甲环酸,术中持续泵注1mg.kg-1.h-1至术毕;对照组(B组,n=20)持续泵注生理盐水。分别于术前,术中3h,术后第1天和第3天抽取中心静脉血检测血栓弹力图(TEG),凝血常规,包括凝血酶原时间(PT),部分活化凝血酶时间(APTT)和纤维蛋白原(Fib)含量,及血浆D-二聚体含量,并记录术中出血量和术后24h胸腔引流量。结果T组术中、术后CI均明显高于对照组,术后LY30显著低于对照组(P<0.05);T组术中和术后D-二聚体含量均明显低于C组(P<0.01);T组术中出血量和术后24h胸腔引流量明显少于C组(P<0.01)。结论氨甲环酸抑制了纤溶活性的增强,改善了开胸手术后早期的低凝状态,显著减少了开胸手术围术期的血液丢失。     

Identification of SARS-CoV-2 entry inhibitors among already approved drugs

To discover effective drugs for COVID-19 treatment amongst already clinically approved drugs,we developed a high throughput screening assay for SARS-CoV-2 virus...     

大动脉硬化与心源性栓塞脑梗死预后的分析

目的分析大动脉硬化和心源性栓塞所致青年人脑梗死的预后。方法两组病人采用相似的药物治疗并辅以运动康复训练。分别于入院48小时和住院治疗30天后,对两组病人神经功能缺损程度和日常活动能力（ADL）巴氏指教（BI）进行评估。结果心源性栓塞组其脑梗死范围较大,入院时神经功能缺损程度及日常活动能力较差。治疗1个月后,心源性栓塞组神经功能损害的恢复和提高均差于大动脉硬化组。结论大动脉硬化和心源性栓塞是青年人脑梗死的主要原因,心源性栓塞组脑梗死预后差于大动脉硬化组。