Cryogenic Reliability Evaluation of Glass Fabric–Reinforced Composites Using Novel Slip-Prevention Method

Glass fabric–reinforced composites are the main insulating material components of the secondary barrier of cargo containment systems (CCSs), because they prevent liquefied natural gas (LNG) leakage during transport. Nevertheless, it is difficult to evaluate the material performance of glass fabric–reinforced composites at cryogenic temperatures (−163 °C) because it takes approximately 7 days to prepare the test specimens and because the slip-based test frequently fails. Although glass fabric–reinforced composites for the secondary barrier of LNG CCSs show various structural vulnerabilities, enhancing their material performance is significantly limited owing to the reasons mentioned above. This study evaluated the structural vulnerabilities and failure characteristics of glass fabric–reinforced composites by using the slip-prevention test method to determine the level difference and adhesive vacancies. The failure surface and the thermal expansion of the composites were also observed, to analyze their mechanical characteristics. By adopting our proposed test procedure, the failure rate of the experiment decreased by approximately 80%, and the sample preparation time for manufacturing was significantly shortened, to 1 day.     

9-硝基喜树碱脂质体的制备及大鼠肺部给药药动学

目的制备9-硝基喜树碱(9-NC)脂质体,研究其经大鼠肺部给药后的体内药动学行为。方法以薄膜分散-超声法制备9-NC脂质体,用粒度测定仪测定粒径,采用离心法分离脂质体和未包封药物并用HPLC法测定包封率,通过肺部滴注给药考察脂质体在大鼠体内的药动学行为,用液液萃取法处理血浆样品,反相HPLC法测定不同时间点大鼠血浆中的药物浓度。结果9-NC脂质体平均粒径为167.6nm,包封率为(91.51±2.63)%(n=3)。9-NC脂质体和溶液剂经肺部给药后,体内药物动力学参数分别为t1/2(3.88±0.90)h和(0.72±0.07)h,AUC0→t(215.88±16.47)μg·h·L-1和(95.29±6.04)μg·h·L-1,MRT(3.72±1.65)h和(1.10±0.08)h。结论与溶液剂相比,9-NC脂质体肺部给药后具有一定的缓释作用。     

Liposomal irinotecan (Onivyde): Exemplifying the benefits of nanotherapeutic drugs

Irinotecan is a topoisomerase inhibitor, widely used in treatment of malignancies including pancreatic ductal adenocarcinoma (PDAC) as part of the FOLFIRINOX regimen prescribed as a first‐line treatment in several countries. However, irinotecan has not been successfully introduced as a second‐line treatment for pancreatic cancer and few randomized clinical studies have evaluated its added value. Efficacy of liposomal irinotecan (nal‐IRI) combined with 5‐fluorouracil and leucovorin (5‐FU/LV) was reported in the phase III NAPOLI‐1 trial in metastatic PDAC following failure of gemcitabine‐based therapy. Several features of nal‐IRI pharmacokinetics (PK) could result in better outcomes versus nonliposomal irinotecan. Irinotecan is a prodrug that is converted to active SN‐38 by carboxylesterase enzymes and inactivated by cytochrome P450 3A4/3A5. SN‐38 is inactivated by UGT1A1 enzymes. Individual variations in their expression and activity could influence enhanced localized irinotecan activity and toxicity. Liposomal irinotecan exploits the enhanced permeability and retention effect in cancer, accumulating in tumor tissues. Liposomal irinotecan also has a longer half‐life and higher area under the concentration‐time curve (0–∞) than nonliposomal irinotecan, as the liposomal formulation protects cargo from premature metabolism in the plasma. This results in irinotecan activation in tumor tissue, leading to enhanced cytotoxicity. Importantly, despite the longer exposure, overall toxicity for nal‐IRI is no worse than nonliposomal irinotecan. Liposomal irinotecan exemplifies how liposomal encapsulation of a chemotherapeutic agent can alter its PK properties, improving clinical outcomes for patients. Liposomal irinotecan is currently under investigation in other malignancies including biliary tract cancer (amongst other gastrointestinal cancers), brain tumors, and small‐cell lung cancer.     

气管切开后拔管困难原因分析及处理

目的探讨可弯曲支气管镜(纤维支气管镜/电子支气管镜,简称支气管镜)在气管切开术后拔管困难诊治中的意义。方法回顾性分析17例经可弯曲支气管镜检查确诊和治疗的气管切开术后拔管困难患者的临床资料。结果 17例拔管困难患者,除1例脑外伤气管上端瘢痕挛缩伴闭锁拔管失败外;其余16例患者均成功拔管,拔管成功率94.1%。除1例患者出现支架移位、1例患者拔管后出现呼吸困难外,余无不良事件发生,无致死性并发症发生。结论可弯曲支气管镜在气管切开术后拔管困难患者诊治中起着重要作用,且安全可靠,值得临床推广。     

sox9基因过表达诱导人骨髓基质干细胞向软骨细胞分化

目的：观察转录因子sox9过表达对骨髓基质干细胞的诱导作用。方法：分离纯化培养人胎儿骨髓基质干细胞。利用脂质体转染基因sox9，抗生素G418筛选，分别取2d和16d转染后取细胞爬片做融合表达蛋白FLAG免疫组织化学鉴定和Ⅱ型胶原免疫组化，以空载体转染细胞作对照。结果：骨髓基质干细胞呈短小纺锤形成纤维细胞，早期较小，中后期体积变长变大。600μg／ml的G418是最适筛选浓度。转染后第2d和16d的细胞都表达sox9基因融合表达的标签蛋白F1AG。第2d和16d转染效率分别为90％和72％。转染后16d的MSC表达Ⅱ型胶原，转后2d实验组和对照组都为阴性。结论：sox9能稳定转染骨髓基质干细胞，sox9过表达并诱导MSCs出现软骨细胞表型。     

颈椎损伤后手术中脊髓保护措施的效果探讨

目的探讨颈椎损伤后手术中脊髓保护措施的效果。方法强迫位下清醒/快速诱导气管插管后,部分患者行控制性降压、脱水、利尿、适度过度通气、皮层体感诱发电位(CSEP)监测;截瘫患者行双下肢弹性绷带缠裹。结果快速诱导插管较清醒插管难度明显降低(P<0.05),术后并发症减少;控制性降压明显减少术中出血量(P<0.01),显露清晰,方便椎管内操作;脱水、利尿、适度过度通气使椎管内压明显降低,硬膜、脊髓损伤减少;截瘫患者弹性绷带缠裹后,术中脊髓血供改善;CSEP监测可规避术中误伤脊髓的发生。结论颈椎手术中脊髓保护应从诱导插管、术中管理多个环节加以落实,方可获得理想的脊髓保护效果。     

苦参总生物碱固体脂质纳米粒的制备工艺研究

目的 探索苦参总生物碱(TA)磷脂复合物固体脂质纳米粒(TA-PC-SLN)的制备工艺及处方优化,并对其进行体外评价.方法 建立高效液相色谱(HPLC)法同时测定TA中4个指标成分苦参碱(MT)、氧化苦参碱(OMT)、槐果碱(SC)、氧化槐果碱(OSC),并进行方法学验证.称取TA、卵磷脂共同溶于乙醇制备磷脂复合物;采...     

Development of a Flexible Metamaterial Film with High EM Wave Absorptivity by Numerical and Experimental Methods

The present study is intended to develop and test a cost-effective and efficient printing method for fabricating flexible metamaterial film with high electromagnetic wave absorptivity. The film can be easily applied to the surfaces with curved aspects. Firstly, numerical parametric study of the absorption characteristics of the film is performed for the range of frequency varying from 2.0 to 9.0 GHz based on commercial software package. Secondly, the flexible metamaterial films are fabricated, and experiments are conducted. The flexible metamaterial film consists of a flexible dielectric film made of polyimide (PI) and an array of split-ring resonators. The split-ring resonators of different geometric dimensions are fabricated on the PI film surface by using a silver nanoparticles ink jet printer. The performance of the flexible structure is then measured and dependence of operation frequency with higher absorptivity on the dimensions of the split-ring resonators is investigated. A comparison between the numerical and experimental data shows that the numerical predictions of the operation frequency with higher absorptivity closely agree with the experimental data.     

经皮肾镜气压弹道超声碎石在肾结石中的效果

目的 B超引导经皮肾镜气压弹道超声联合碎石治疗肾结石的临床效果。方法选择2017年9月-2018年9月医院收治的肾结石患者82例,按照抽签法的要求将其平均分成对照组(41例:B超引导经皮肾镜气压弹道超声治疗)与试验组(41例:输尿管软镜治疗),分析手术时间、住院时间、出血量、结石清除率、结石的残留率。结果试验组的手术时间、住院时间、出血量。优于对照组,数据比较有差异性,P<0.05。对照组的结石清除率高于试验组、结石的残留率低于试验组,相互比较有差异性,P<0.05。结论在肾结石实际治疗期,使用输尿管软镜钬激光碎石治疗方式。     

银杏内酯B脂质体的处方与制备工艺研究

目的 将银杏内酯B（ginkgolide B,GB）制备成脂质体,增加GB在水中的分散性和稳定性。方法 采用超滤离心法分离脂质体与游离药物,HPLC测定脂质体中GB的含量与包封率,采用薄膜分散法制备GB脂质体;通过单因素与正交试验分析药脂比、胆固醇用量、装载量、水化温度和水化时间等因素对包封率的影响,以外观、包封率、粒径为评价指标确定GB脂质体的最佳处方和制备工艺。结果 GB脂质体的最佳处方为10 mg GB、160 mg蛋黄卵磷脂、40 mg胆固醇、8 mg维生素E、58 mg DSPE-PEG2000、5 mL PBS缓冲液;优化后的工艺条件为GB与脂质辅料溶于无水乙醇中,33℃水浴条件下减压旋转蒸发除乙醇,pH 6.5 PBS缓冲液水化脂质薄膜,水化温度35℃,时间120 min,粗脂质体混悬液冰水浴超声6 min,超声功率120 W。制备的GB脂质体混悬液微泛蓝色乳光、可透光,粒径为（126±4） nm,包封率>87%,放置24 h无聚集、无沉降。结论 采用薄膜法在实验室阶段成功制备了稳定的GB脂质体,确定了最优制备处方和制备工艺,为GB制剂的剂型研究做出探索和提供参考。