基于AMPK/ULK1自噬通路探讨人参败毒散对溃疡性结肠炎黏膜屏障的干预机制

目的 研究人参败毒散调控腺苷酸活化蛋白激酶/Unc-51样激酶1（AMPK/ULK1）自噬通路抑制溃疡性结肠炎小鼠黏膜屏障损伤的作用机制。方法 将60只SD大鼠随机分为6组,分为正常组,模型组,柳氮磺胺吡啶肠溶片组（西药组）,人参败毒散高、中、低剂量组。通过2,4,6-三硝基苯磺酸（TNBS）/50%乙醇诱导UC模型,西药组（0.3125 g·kg^-1）、人参败毒散高、中、低剂量组（31.2、15.6、7.8 g·kg^-1）灌胃2周后,检测结肠组织病理学改变;实时荧光定量聚合酶链式反应（Real-time PCR）检测腺苷酸活化蛋白（AMPKα）mRNA表达水平;蛋白免疫印迹法（Western blot）检测紧密连接蛋白中闭合蛋白（Occludin）、紧密连接蛋白蛋白-2（Claudin-2）、自噬标志蛋白p62、微管相关蛋白1轻链3B（LC3B）及AMPK/ULK1通路磷酸化蛋白p-AMPK、p-ULK1的表达水平。结果 与正常组比较,模型组结肠损伤评分明显上调（P<0.05）,AMPKα mRNA表达明显下调（P<0.05）,p-AMPK、p-ULK1、Occludin蛋白水平及LC3Ⅱ/Ⅰ明显下调（P<0.05）,而p62、Claudin-2蛋白水平明显上调（P<0.05）;与模型组比较,人参败毒散高、中、低剂量组的结肠损伤评分下降,AMPKα mRNA明显上调,p-AMPK、p-ULK1、Occludin蛋白水平及LC3Ⅱ/Ⅰ上升,而p62、Claudin-2蛋白表达下降,以人参败毒散中剂量组干预效应最明显（P<0.05）。结论 人参败毒散可抗肠道黏膜屏障损伤,以人参败毒散中剂量组疗效最佳,其机制可能与激活AMPK/ULK1自噬通路有关,通过加速LC3Ⅰ向LC3Ⅱ转化,促进p62降解,从而改善紧密连接蛋白Occludin、Claudin-2功能,修复肠道机械屏障损伤。     

不同扫描层厚对肝纤维化诊断结果的影响

对不同扫描层厚CT图像肝脏与竖脊肌的CT值进行对比分析 ,结果发现在同等噪声情况下 ,扫描层厚对肝脏和竖脊肌的CT值有不同影响 ,说明了扫描层厚较厚时 ,在CT图像的其它部位 ,噪声较小且不影响诊断结果 ;对于肝来说 ,由于自身结构的原因 ,则会影响到诊断结果 ,因此在通过纹理分析对早期肝纤维化进行辅助诊断时 ,可考虑控制扫描层厚     

POEMS综合征18F-FDG PET/CT显像一例及文献复习

笔者报道了1例多发性周围神经病、脏器肿大、内分泌病变、M蛋白和皮肤病变（POEMS）综合征累及右侧髂骨的18F-氟脱氧葡萄糖（FDG）PET/CT显像的病例,并通过文献复习回顾总结了POEMS综合征的诊断标准及18F-FDG PET/CT的影像表现。POEMS综合征18F-FDG PET/CT显像的报道较多,但影像表现只累及右侧髂骨的病例较少见。了解POEMS综合征的诊断标准、临床表现及实验室检查结果,有助于获取更多的信息并进行准确诊断。     

PGK1-coupled HSP90 stabilizes GSK3β expression to regulate the stemness of breast cancer stem cells

Objective: Glycogen synthase kinase-3β(GSK3β) has been recognized as a suppressor of Wnt/β-catenin signaling, which is critical for the stemness maintenance of breast cancer stem cells. However, the regulatory mechanisms of GSK3β protein expression remain elusive.Methods: Co-immunoprecipitation and mass spectral assays were performed to identify molecules binding to GSK3β, and to characterize the interactions of GSK3β, heat shock protein 90(Hsp90), and co-chaperones. The role of PGK1 in Hsp90 ch...     

基于最优拉丁超立方设计的糖尿病足鞋垫优化设计

目的 提出一种鞋材弹性模量与厚度联合优化设计糖尿病足鞋垫的方法,以降低足底压力和软组织内部应力。方法 通过逆向工程方法建立足部有限元模型,基于足底压力分布特征划分鞋垫压力区域,采用有限元法对接触力学进行研究,为优化过程中调整不同区域内材料的弹性模量和鞋垫前后足厚度奠定基础,使用最优拉丁超立方设计得到最优参数组合。结果 设计的鞋垫增加约37.55%的足底接触面积,跖骨区和足跟区的压力峰值分别降低15.07%、36.96%,足跟处软组织内部应力降低20.83%,足底筋膜张力降低约60%。结论 所提出的方法可用于设计定制鞋垫,设计的个性化鞋垫具有更大的接触面积和降低糖尿病足底溃疡的良好潜力。     

瞬态诱发耳声发射信号的小波阈值去噪

目的瞬态诱发耳声发射信号是从人的外耳检测到的微弱的音频能量,在测试过程中常混入各种随机噪声,本文尝试对瞬态诱发耳声发射信号进行去噪,以提高信号的信噪比,为进一步的临床应用(如频谱分析)奠定基础.方法小波变换阈值法.选用了sym8小波,软阈值处理方法,阈值选取规则为Minimax法.结果去噪后相关系数加大,信噪比提高.信噪比平均提高约10%.结论小波变换阈值法对TEOAE信号去噪取得了较好的效果.     

In situ preparation of Ag nanoparticles on silicon wafer as highly sensitive SERS substrate

An intensive surface enhanced Raman scattering (SERS) effect is realized by ordered Ag nanoparticles (NPs) in situ grown on silicon wafer directly using (3-aminopropyl) trimethoxysilane (APS) as both the surface modifier and reducing agent. The as-prepared ordered Ag NPs based SERS substrate shows excellent performance in detecting glycerin (an important integration in liquid super lubricating system) as well as conventional Rhodamine 6G (R6G, a kind of dye organic pollutant). The enhancement factor (EF) achieves 4-fold for glycerin and 10-fold for R6G (allowing for detecting as low as 10⁻¹¹ M aqueous R6G), confirming the high sensitivity. The limited relative standard deviations (RSD) of the enhancement factors are within 15% for both glycerin and R6G, indicating the excellent uniformity. This remarkable progress is ascribed to the advantages of APS in improving adsorption and modulating distribution of Ag NPs on silicon, which results in a large local electric field to enhance the Raman signals. The SEM and UV-visible absorption spectrum characterization verified the contribution of APS in SERS improvement by investigating the influence of APS content and reduction time during the preparation process. All these advances imply that the SERS substrates prepared by Ag NPs in situ grown on silicon wafer have great potential application in real-time interface state tracing and sensitive detection.

An intensive surface enhanced Raman scattering (SERS) effect is realized by ordered Ag nanoparticles (NPs) in situ grown on silicon wafer directly using (3-aminopropyl) trimethoxysilane (APS) as both the surface modifier and reducing agent.     

Phylogenetic and pathogenic analyses of two virulent Newcastle disease viruses isolated from Crested Ibis (Nipponia nippon) in China

The crested ibis is one of the most endangered birds in the world, found only in Shaanxi Province in Central China, and it has been reintroduced in Sadogashima in Japan. Two Newcastle disease virus (NDV) isolates were collected from sick crested ibises, and their pathogenic and phylogenetic characteristics were investigated. The results showed that they are virulent, with intracerebral pathogenicity indices of 1.46–1.83 and a mean time of death of 54.4–84.4 h. They shared the same virulent motif ¹¹²-R-R-Q-K-R-F-¹¹⁷ at the F protein cleavage site. The phylogenetic analysis revealed that both isolates were clustered with class II NDVs, with one in genotype VIId and another in a novel genotype (provisionally designated as VIi). The two isolates shared high homology with the strains isolated from poultry flocks in the same region from 2006 to 2010. We first isolated and characterised the NDV isolates from crested ibises, one of which showed new genetic characteristics and formed a new subgenotype with isolates from pigeons and ostriches in the same area. These data are useful for further epidemiological studies on NDV and the protection of crested ibises.     

肝内胆管细胞癌患者术后的预后影响因素研究

背景与目的:肝内胆管细胞癌(ICC)为常见的肝脏胆道系统肿瘤。临床上40%~50%的ICC患者临床确诊时需要进行手术切除病灶,本研究旨在探讨ICC患者切除术后患者预后的影响因素。方法:选取2016年1月-2017年7月接受根治性手术治疗的67例ICC患者临床资料进行回顾性分析,并进行随访(电话、门诊定期随诊的方式),主要记录患者的死亡、生存情况及患者1、2、3年存活率;统计两组患者的基础资料,分析影响ICC患者生存时间的主要危险因素。随访截止2019年10月30日。结果:全组67例患者,其男41例,女26例;年龄42~75岁,平均年龄(61.4±9.9)岁,肿瘤直径2.9~9.4 cm,平均直径(4.1±2.1)cm,病灶数目(1.2±0.4)个。在36个月的随访中3例患者失访,术后1年40例患者生存(59.70%),术后2年24例患者生存(35.82%),术后3年12例患者生存(17.91%);中位生存时间22.5个月。采用Log-rank秩检验发现:病灶最大径、病灶数目、血管浸润、淋巴结转移、远处转移、分化程度、CA19-9、TNM分期与ICC患者术后的生存时间有关。采用Cox比例回归风险模型分析发现:病灶多发(OR=1.729)、血管浸润(OR=2.085)、淋巴结转移(OR=1.816)、远处转移(OR=1.902)、低分化(OR=1.560)、CA19-9≥37 U/mL(OR=1.719)是影响ICC患者术后远期预后的独立危险因素。结论:ICC患者切除术后总体生存率及中位生存时间不理想,病灶多发、血管浸润、淋巴结转移、远处转移、低分化、CA19-9≥37 U/mL是影响ICC患者远期预后的独立危险因素。对有相关因素的患者应加强随访,必要时可以联合放化疗综合治疗进而改善患者的预后。