胃癌患者血液样品的光谱分析

发布时间：2018-03-09 23:27

本文选题：光谱学　切入点：表面增强拉曼散射　出处：《郑州大学》2015年硕士论文　论文类型：学位论文

【摘要】：胃癌是常见恶性肿瘤之一,南美、东欧和东亚是胃癌的高发地区,全世界每年有70多万人死于胃癌。在中国胃癌的发病率位居各类肿瘤第三,发病有明显的地域性差异,西北青海地区与东部沿海地区胃癌发病率相比南方广西广东地区明显高出许多,男女发病比例近似为2:1,好发年龄在54岁以上。虽然胃癌发病率颇高,但鉴别起来还是比较困难,常规的胃癌诊断过程包含体检,组织检查和影像学检查,但这些方法都存在着浸入性、耗时等特点,当确诊是胃癌为时已晚。从而早期诊断对胃癌患者的治疗具有重要意义,本文采用表面增强拉曼光谱技术和紫外-可见吸收光谱技术对胃癌患者和健康人的血液样本进行分析和统计。结果显示,紫外-可见吸收光谱所包含的信息量太少,很难对健康人和胃癌患者的血液样品进行很好区分。而血红蛋白拉曼光谱是在血氧饱和度定量测定,血液代用品的高铁血红蛋白含量检测及疾病状态下异常血红蛋白检测中优势都较为明显。本文采用微波加热方法制备银胶体粒子,该方法简单、快捷。分别对20例胃癌患者和11例健康人的血红蛋白进行表面增强拉曼散射,得到重复性很高和特征峰突出的拉曼谱。通过SERS谱峰归属分析显示胃癌患者血红蛋白中的吡咯环、酪氨酸和苯丙氨酸都低于正常人。对血红素结构进行分析与讨论,当血红蛋白与氧结合之后,Fe2+离子处于低自旋态,离子半径因缩小而位移了0.75?从而落入血红素卟啉环平面中央的孔隙之中。这种空间变化使与铁相连的F8 His受到牵动,会使珠蛋白中的两股螺旋之间空隙缩小,导致将HC2酪氨酸排挤出空隙。利用这一机理,通过1560 cm-1的吸收峰进一步证实胃癌患者酪氨酸含量低于正常人。结合主成分分析(PCA)的方法,对所得的拉曼散射光谱建立多元统计模型并进行分析与统计,得到的光谱峰值的降维三维散点图,这张图可以非常好的区分健康人与胃癌患者。利用判别分析方法得出该算法诊断胃癌的灵敏度和特异性分别为90.0%和90.9%,总判别正确率为90.3%。研究结果表明,氧合血红蛋白表面增强拉曼(SERS)的光谱统计分析是可以作为一种新型胃癌的诊断方法。
[Abstract]:Gastric cancer is one of the most common malignant tumors. The incidence of gastric cancer is high in South America, Eastern Europe and East Asia. More than 700,000 people die of gastric cancer every year in the world. The incidence of gastric cancer in China ranks third among all kinds of tumors, and there are significant regional differences in the incidence of gastric cancer. The incidence of gastric cancer in northwest Qinghai and eastern coastal areas is much higher than that in southern Guangxi and Guangdong. The incidence ratio of male and female is approximately 2: 1, and the predilection age is over 54. Although the incidence of gastric cancer is quite high, it is still difficult to distinguish. The routine diagnosis of gastric cancer includes physical examination, tissue examination and imaging examination, but these methods have the characteristics of immersion, time consuming and so on. When the diagnosis of gastric cancer is too late, the early diagnosis is of great significance for the treatment of gastric cancer patients. Surface enhanced Raman spectroscopy and UV-Vis absorption spectroscopy were used to analyze and statistics the blood samples of patients with gastric cancer and healthy people. The results showed that the UV-Vis absorption spectra contained too little information. It is difficult to distinguish the blood samples of healthy people from those with gastric cancer, and the hemoglobin Raman spectroscopy is measured quantitatively by oxygen saturation. The advantages of methemoglobin content in blood substitutes and abnormal hemoglobin in the condition of disease are obvious. In this paper, silver colloid particles were prepared by microwave heating. Fast. Surface enhanced Raman scattering of hemoglobin in 20 patients with gastric cancer and 11 healthy persons was carried out, and the Raman spectra with high reproducibility and prominent characteristic peaks were obtained. The pyrrole ring in hemoglobin of gastric cancer patients was revealed by SERS spectrum analysis. Both tyrosine and phenylalanine are lower than normal people. The heme structure is analyzed and discussed. When hemoglobin is combined with oxygen, Fe _ 2 ion is in a low spin state, and the ionic radius is shifted from 0.75 to 0.75? This spatial change in the center of the heme porphyrin ring affects the iron-linked F8 His, which reduces the gap between the two helices in globin, leading to the extrusion of HC2 tyrosine out of the void. The absorption peak of 1560 cm-1 further confirmed that the tyrosine content of gastric cancer patients was lower than that of normal persons. The reduced dimension 3D scatter plot of the peak value of the spectrum is obtained, The sensitivity and specificity of the algorithm for the diagnosis of gastric cancer were 90.0% and 90.9, respectively, and the total discriminant accuracy was 90.3%. Spectral statistical analysis of surface enhanced Raman SERS is a new diagnostic method for gastric cancer.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R735.2;O657.3

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