System to screen and purify active ingredients from herbal medicines using hydrogel-modified human umbilical vein endothelial cell membrane chromatography coupled with semi-preparative high-performance liquid chromatography-offline-high-performance liquid chromatography-mass spectrometry

Analytical screening and validation systems based on a combination of cell membrane chromatography and two-dimensional chromatography-tandem mass spectrometry are incapable of providing prepared samples containing the active ingredients found in traditional Chinese medicine; therefore, these samples cannot be directly used in subsequent studies. In this study, a semi-preparative cell membrane chromatography column was developed using a hydrogel-modified carrier and human umbilical vein endothelial cells to optimize prepared conditions, such as hydrogel polymerization, cell fragmentation, and cell membrane volume. This increased the binding ratio of membrane protein and carrier to 15.79 mg/g. The column was systematically evaluated using multitarget tyrosine kinase inhibitors that displayed good specificity and reproducibility. Subsequently, using the column coupled with a semi-preparative high-performance liquid chromatography-offline-high-performance liquid chromatography-mass spectrometry system, 15 active ingredients were screened and purified from Indigo naturalis, and five main components were identified: l -lysine, oxyresveratrol, tryptanthrin, isorhamnetin, and indirubin. Furthermore, the pharmacological effects of the ingredients were confirmed using cell proliferation and apoptosis assays. Results revealed potent proliferation-inhibiting and apoptosis-promoting abilities on human chronic myelogenous leukemic cells and human promyelocytic leukemic cells (p < 0.001). Overall, the system presented screening and purification functions that could be used to prepare I. naturalis samples acting on the epidermal growth factor receptor and vascular endothelial cell growth factor.     

Phase contrast imaging of preclinical portal vein embolization with CO2 microbubbles

Preoperative portal vein embolization (PVE) is employed clinically to avoid postoperative liver insufficiency. Animal models are usually used to study PVE in terms of mechanisms and pathophysiological changes. PVE is formerly monitored by conventional absorption contrast imaging (ACI) with iodine contrast agent. However, the side effects induced by iodine can give rise to animal damage and death. In this study, the feasibility of using phase contrast imaging (PCI) to show PVE using homemade CO₂ microbubbles in living rats has been investigated. CO₂ gas was first formed from the reaction between citric acid and sodium bicarbonate. The CO₂ gas was then encapsulated by egg white to fabricate CO₂ microbubbles. ACI and PCI of CO₂ microbubbles were performed and compared in vitro. An additional increase in contrast was detected in PCI. PCI showed that CO₂ microbubbles gradually dissolved over time, and the remaining CO₂ microbubbles became larger. By PCI, the CO₂ microbubbles were found to have certain stability, suggesting their potential use as embolic agents. CO₂ microbubbles were injected into the main portal trunk to perform PVE in living rats. PCI exploited the differences in the refractive index and facilitated clear visualization of the PVE after the injection of CO₂ microbubbles. Findings from this study suggest that homemade CO₂ microbubbles‐based PCI is a novel modality for preclinical PVE research.     

Impact of NIR wavelength lighting in image acquisition on finger vein biometric system effectiveness

Finger vein biometric systems become increasingly more popular because they offer higher security comparing to other authentication solutions with respect to positive persons experience. Those systems operate on near infrared light (NIR) in wavelength range from around 700 to 1000 nm, however dedicated research to determine impact of NIR lighting on biometric system effectiveness has not been conducted and presented in the literature ever before. In this paper the study of correlation between wavelengths in NIR spectra and effectiveness of person identification in a biometric system is presented. To achieve that goal, a new model of image acquisition system allowing change of light wavelengths has been created and NIR finger vein dataset containing 11 556 images was established. Furthermore, this model was used to perform experimental work and proof that some NIR wavelengths better suit for vein patterns acquisition, allowing to increase the recognition effectiveness of finger vein biometric systems.     

细胞相容性聚氨酯的合成及其细胞相容性研究

在紫外光和过氧化氢的共同作用下,过氧化氢基团被引人到聚氨酯膜(PU)表面.将丙烯酸羟乙酯(HEA)吸附于氧化后的PU膜表面,在紫外光下实现了膜表面的接枝,并考察了接枝膜的表面性能.人体脐带静脉内皮细胞粘附和生长的研究表明,HEA接枝后的PU表面细胞粘附率显著提高,细胞的生长速率加快,增值率提高.     

浅埋偏压隧道出口变形机理及稳定性分析

以皖南某公路浅埋偏压隧道出口段高边坡为研究对象,提出了"零开挖进洞"的施工方案,并结合洞口的工程地质条件,采取必要的加固措施。通过对该边坡现场工程地质条件的系统调查,首先对边坡的岩体结构类型及其成因机制、结构面与坡面组合特征进行细致研究,在此基础上通过FLAC^3D数值模拟,结合工程地质条件分析,对其变形破坏机制进行深入探讨。研究结果表明,边坡的变形首先以隧道内侧存在的软弱岩体(挤压错动带、断层)的不均匀压缩为先导,进而引起上部岩体产生由NE向陡缓结构面构成的阶梯状滑动,这将会使隧道构筑物及隧道外壁承受较大的压应力,当压应力超过隧道构筑物及外壁的极限强度时将产生破坏,从而诱发上部岩体产生更大规模的地质灾害。基于此,隧道进洞开挖前首先应对上部岩体进行加固处理,避免隧道构筑物及隧道外壁产生应力集中现象。     

投影式头戴静脉显像光学系统的设计

为了辅助静脉穿刺及相关的医疗操作, 设计了一款基于投影式头戴显示器(HMPD)的静脉显像系统, 其光学系统由近红外成像系统和穿透型HMPD构成。利用光学设计软件ZEMAX优化设计近红外成像系统, 使其具有F/2.6的大数值孔径, 有利于弱反射红外光的收集成像。穿透型HMPD采用与近红外成像系统相同的光学结构, 有利于简化系统的加工装调。设计结果表明, 近红外成像系统成像质量优异, 分辨率达到QXGA(2 048×1 536)。穿透型HMPD具有18 mm的大出瞳直径及25 mm的大出瞳距离, 场曲小于0.03 D, 畸变小于0.32%, 达到QXGA分辨率显示模式。与现行的静脉显像系统相比, 本显像系统结构简单紧凑、佩戴舒适, 且具有超高分辨率, 是一款适用于辅助医疗的目视系统。     

新型苯基噻吩-2-基甲酮类化合物的合成及其对人脐静脉内皮细胞的保护活性

合成了13个具有新型结构的苯基(噻吩-2-基)甲酮类化合物,其中3个化合物(9b,10b,11b)未见文献报道,目标化合物的结构均经ESI-MS、1H NMR和13C NMR等技术手段进行了确证。 对H2O2诱导的人脐静脉内皮细胞(HUVECs)氧化损伤保护活性的结果显示,对位甲氧基以及两个氯原子取代的活性较好。 初步构效关系表明,苯基噻吩甲酮母环上取代基的位置、数目、类型是影响化合物活性的主要原因。     

手背静脉图像预处理算法研究

静脉识别是一种新兴的生物特征识别技术。介绍了静脉图像的采集原理,根据静脉血管的特点,重点对静脉图像预处理进行了研究。静脉图像预处理可分为静脉图像的标准化和静脉图像的二值化两个部分。针对二值化问题,提出了彩动态阈值法对静脉图像进行处理和增强,得到了较好的结果。     

Synthesis and goat pulmonary vasodilatory activity of some novel 1,3,4-oxadiazoles

A novel series of[(1Z)-1-(2,2-disubstituted-5-pyridin-4-yl-1,3,4-oxadiazol-3(2H)-yl) ethylidene] (PSMB1–PSMB15) were synthesized as title compounds. The synthesis route included the cyclization of carbonyl hydrazone in the presence of excess of acetic anhydride and subsequent condensation with various aromatic amines. All the title compounds were characterized by IR, ¹H NMR, MS and elemental analysis. They were screened for their goat pulmonary vein relaxant activity. Compound PSMB9 was found the most active derivative exhibiting 83.33% relaxation. Isosorbide dinitrate was used as the standard drug for goat pulmonary vein relaxant activity.