基于虚拟仪器的人体皮肤组织吸收光谱检测平台

本文运用光电无损检测技术,采用皮外反射式测量方法,通过光纤光谱仪和虚拟仪器构建人体皮肤组织吸收光谱检测平台.该平台适合于光子-组织相互作用基础研究及激光美容临床检测,可协助医师进行病理诊断和病变程度判别.文中给出几个吸收光谱的检测结果.     

Mass spectral analysis and imaging of tissue by ToF-SIMS—The role of buckminsterfullerene, C60, primary ions

Recent developments in desorption/ionisation mass spectrometry techniques have made their application to biological analysis a realistic and successful proposition. Developments in primary ion source technology, mainly through the advent of polyatomic ion beams, have meant that the technique of secondary ion mass spectrometry (SIMS) can now access the depths of information required to allow biological imaging to be a viable option.Here the role of the primary ion C₆₀⁺ is assessed with regard to molecular imaging of lipids and pharmaceuticals within tissue sections. High secondary ion yields and low surface damage accumulation are demonstrated on both model and real biological samples, indicating the high secondary ion efficiency afforded to the analyst by this primary ion when compared to other cluster ion beams used in imaging. The newly developed 40 keV C₆₀⁺ ion source allows the beam to be focused such that high resolution imaging is demonstrated on a tissue sample, and the greater yields allow the molecular signal from the drug raclopride to be imaged within tissue section following in vivo dosing.The localisation shown for this drug alludes to issues regarding the chemical environment affecting the ionisation probability of the molecule; the importance of this effect is demonstrated with model systems and the possibility of using laser post-ionisation as a method for reducing this consequence of bio-sample complexity is demonstrated and discussed.     

650nm光在Intralipid-10%中分布的测量和分析

本文提出一种用光纤测定光在生物组织模型Iitralipid内部光分布的方法并测定了650nm激光在Iitralipid 10%中的分布,该方法与各向同性球形光纤探头探测组织内光分布是一种互补的方法。实验结果揭示了在生物组织模型中不同方向散射光的分布规律,表明了不同的组织光学参数和不同直径的入射光束与光分布之间的关系;采用外推边界条件的漫射方程解拟合前向散射光的测量数据确定了组织模型的散射系数和吸收系数并得到较好的结果,所测量的光学参数与公开发表的结果比较其差别在2 35%以内。     

Gold nanoparticle-enhanced surface plasmon resonance measurement with a highly sensitive quantification for human tissue inhibitor of metalloproteinases-2

Two different methods for the quantification of human tissue inhibitor of metalloproteinases-2 (TIMP-2) were developed using surface plasmon resonance (SPR) and gold nanoparticles for signal enhancement. The first method, a competitive assay, used TIMP-2 immobilized to the sensor surface and the inactive form of matrix metalloproteinase-2 (proMMP-2) (EC 3.4.24.24) adsorbed to gold nanoparticles. The sensor signals resulting from the interaction of MMP-2-gold nanoparticles with immobilized TIMP-2 were inversely proportional to the amounts of TIMP-2 of the sample. The measuring range for TIMP-2 was about 15–180 pM. The second method, a one-step sandwich assay, used proMMP-2 immobilized to the sensor surface and an anti-TIMP-2 monoclonal antibody coupled to gold nanoparticles. The lower detection limit of this assay format was 0.5 pM of TIMP-2. The binding signals were highly reproducible up to 100 pM of the inhibitor. The improvements obtained in TIMP-2 quantification over already existing tests could contribute to a better understanding and diagnosis of diseases like cancer.     

魔角旋转核磁共振代谢组学方法对镧、铈急性生物效应的比较研究

利用高分辨魔角旋转核磁共振(MAS 1H NMR)技术对腹腔注射不同剂量[2, 10, 50 mg/kg(体重)]的硝酸镧[La(NO3)3]和硝酸铈[Ce(NO3)3] 的雄性Wistar大鼠肝、肾组织的MAS 1H NMR谱进行比较分析, 研究了La(NO3)3和Ce(NO3)3的急性生物效应, 并结合模式识别技术对不同剂量La(NO3)3和Ce(NO3)3的急性生物效应进行了分类. 研究结果表明, La(NO3)3对大鼠的急性毒性主要表现为肝毒, Ce(NO3)3对大鼠肝、肾同时造成损伤. 该方法可用于其它稀土及金属化合物的毒性预测和毒理学研究.     

A study on the bioactivity of chitosan/nano-hydroxyapatite composite scaffolds for bone tissue engineering

In order to increase the biocompatibility and bioactivity of chitosan, hydroxyapatite had been in situ combined into chitosan scaffolds. The bioactivity of the composite scaffolds was studied by examining the apatite formed on the scaffolds by incubating in simulated body fluid and the activity of preosteoblasts cultured on them. The apatite layer was assessed using scanning electronic microscope (SEM), X-ray diffraction (XRD), Fourier-Transformed Infrared spectroscopy (FTIR) and weight measurement. Composite analysis showed that after incubation in simulated body fluid on both of the scaffolds carbonate hydroxyapatite was formed. With increasing nano-hydroxyapatite content in the composite, the quantity of the apatite formed on the scaffolds increased. Compared with pure chitosan, the composite with nano-hydroxyapatite could form apatite more readily during the biomimetic process, which suggests that the composite possessed better mineralization activity. Furthermore, preosteoblast cells cultured on the apatite-coated scaffolds showed different behavior. On the apatite-coated composite scaffolds cells presented better proliferation than on apatite-coated chitosan scaffolds. In addition, alkaline phosphatase activities of cells cultured on the scaffolds in conditioned medium were assessed. The cells on composite scaffolds showed a higher alkaline phosphatase activity which suggested a higher differentiation level. The results indicated that the addition of nano-hydroxyapatite improved the bioactivity of chitosan/nano-hydroxyapatite composite scaffolds. On the other hand, that is to say composition of substrates could affect the apatite formation on them, and pre-loaded hydroxyapatite can enhance the apatite-coating. It will also be significant in preparation of apatite-coating polymer scaffolds for bone tissue engineering.     

Method of immobilization of carboxymethyl-dextran affects resistance to tissue and cell colonization

Coatings from carboxymethylated dextrans (CMDs) were fabricated, analyzed by XPS, and investigated for their ability to inhibit corneal epithelial tissue outgrowth and bovine corneal epithelial cell attachment and growth. CMDs with differing degrees of carboxymethyl substitution and various molecular weights were synthesized by the solution reaction of dextrans with bromoacetic acid under different reactant ratios. The CMD compounds thus obtained were attached onto aminated surfaces produced in two ways: by the plasma deposition of a coating from n-heptylamine vapour, and by the plasma deposition of an acetaldehyde coating onto whose surface aldehyde groups the polyamine compounds polylysine, polyethyleneimine and polyallylamine were immobilized to provide platforms for CMD immobilization. XPS spectra showed that the latter route produced thicker coatings than the former approach. CMD molecules attached directly onto the plasma-fabricated amine surface supported some tissue migration; the extent of carboxymethyl substitution and the molecular weight of the CMDs had little influence. For CMDs immobilized via polyamine spacers, on the other hand, tissue outgrowth was completely inhibited, and again there were no discernible effects from the extent of carboxymethyl substitution and the molecular weight of the CMDs. In assays involving cell attachment and growth, analogous observations were found. Thus, the mode of immobilization of these polysaccharide coatings is the dominant factor in their anti-fouling performance, suggesting that optimization of the architecture of polysaccharide coatings may be an important factor for maximizing their cell-repellent abilities.     

氨基酸植物组织传感器的研究

选择苹果及仙人球的组织切片作生物催化材料,同氨气敏电极组合,研制了2种对L-谷氨酰胺及L-天冬酰胺选择响应的新型的组织传感器。研究和讨论了传感器的最佳工作条件。用该组织传感器测定了L-天冬酰胺脱氨酶和L-谷氨酰胺脱氨酶的动力学参数K_m和V_m。     

正交试验选择组织电极的最佳分析条件

本文用正交试验法对花椰菜组织Ｌ－抗坏血酸传感器和香蕉组织儿茶酚类化合物传感器的分析条件进行了优化，通过与单因子分析方法及４种儿茶酚类化合物之间正交试验结果的比较，说明用正交试验选择组织传感器的最佳分析条件，在少量的试验次数内，得到较多的分析实验信息，是一种较理想的试验方法。     

大鼠脑组织中不同部位单胺类神经递质含量的HPLC测定

单胺类神经递质,多巴胺(DA)、去甲肾上腺素(NA)和肾上腺素(A)是哺乳动物和人类中枢重要的信息传递物质。了解脑组织中各部位单胺类神经递质的含量对于研究其生理功能、有关疾病的诊断和药物及手术疗效的评价均有重要的意义。