胃和结直肠癌的傅里叶变换红外光谱研究

利用傅里叶变换红外光谱仪及带ATR探头的中红外光纤系统测定了手术切除的胃癌、结直肠癌及相应的正常组织共31对标本粘膜面的反射红外光谱. 结果表明, 与正常组织相比, 癌组织的红外光谱发生明显变化: (1) 与脂类相关的谱带2955, 2920, 2870, 2850和1740 cm-1出现几率明显低于正常组织(P<0.001), I1460/I1400(I为峰强度)明显降低(P<0.001), 表明癌组织的脂类相对含量降低; (2) 与蛋白质相关谱带N—H和O—H明显红移(P=0.025), 表明N—H和O—H的氢键化程度增加, 癌组织的I3375/I1460, I1640/I1460和I1550/I1460明显升高(P<0.01), 表明癌组织的蛋白质相对于脂类的含量增加, 癌组织的HW1550/I1550(HW为半高宽)明显升高(P=0.036), HW1550则明显降低(P=0.05), 表明癌组织中蛋白质的二级结构发生显著变化; (3) 与醣类相关谱带中癌组织的I1160/I1460降低(P=0.002), 结合组织化学染色, 推测可能是癌组织表面的糖蛋白明显减少造成的, 而I1120/I1460升高(P=0.019)则可能是癌组织表面的糖原颗粒增加所致. (4) 与核酸相关谱带中癌组织的PO的反对称伸缩振动蓝移(P=0.033), 表明癌组织中磷酸基团的氢键化程度降低. 研究结果表明, 红外光谱有望成为诊断恶性肿瘤的有力工具.     

傅里叶变换红外光谱法检测脑肿瘤

应用傅里叶变换红外光谱法检测了28例液氮冻存的离体脑肿瘤样本及其残留物(将脑肿瘤样本从ATR的ZnSe晶片上取下,样本在ZnSe晶片上沾染后留下的物质).结果发现,神经鞘瘤和神经上皮组织肿瘤(如星形细胞瘤等)的主要特征吸收峰存在明显差异,因此可从各个特征吸收峰的峰位、峰形及不同谱峰强度比的变化来初步鉴别脑肿瘤的性质,脑肿瘤组织样品残留物的红外光谱也可反映不同性质脑肿瘤的差异.与脂类糖蛋白以及核酸相关的谱带变化分析表明,通过特征峰强比(I1460cm-1/I1400cm-1,I1160cm-1/I1120cm-1和I1160cm-1/I1080cm-1)来鉴别肿瘤的性质与病理诊断结果的符合率超过85%.     

甲状腺癌微转移淋巴结的红外光谱检测

采用衰减全反射(ATR)探头和傅里叶变换红外光谱(FTIR)仪测定了新鲜离体的甲状腺癌微转移颈部淋巴结(16枚)和非转移性淋巴结(16枚)的FTIR光谱, 配对比较了两组光谱13个谱带的峰位、相对峰强及半高宽等38个FTIR参数, 明确了甲状腺癌微转移淋巴结的光谱特征.结果表明, 与非转移性淋巴结相比, 微转移淋巴结光谱中与蛋白、脂质、糖类和核酸相关的谱带均发生了明显变化:与蛋白质相关的谱带的相对峰强I₃₂₈₀/I₁₄₆₀和I₁₆₄₀/I₁₄₆₀显著升高, 半高宽F₁₆₄₀显著增宽, 而F₁₅₄₆则变窄; 与脂类相关的相对峰强I₁₄₀₀/I₁₄₆₀明显增高; 与糖类相关的1165 cm^-1处谱带的相对峰强I₁₁₆₅/I₁₄₆₀显著降低; 与核酸相关的1240 cm^-1处谱带的相对峰强I₁₂₄₀/I₁₄₆₀显著升高.结果表明, FTIR能够检测出甲状腺癌的微转移淋巴结, 可能应用于甲状腺癌病人的精准手术治疗.     

人体乳腺癌组织红外光谱特征的研究

利用红外光谱法对正常乳腺组织、良性肿瘤和乳腺癌组织进行了对比研究.与正常组织的光谱相比,癌组织中蛋白质的某些氨基酸残基的ν_C-O(H)谱带位置明显向高波数位移,表明组织中该基团中的氢键大部分被破坏.蛋白质分子的氢键化的ν_NH谱带位置向低波数位移,且谱带形状也有所改变,说明NH…O=C氢键化程度增强.核酸的磷酸二酯基团的ν_s,PO₂^-谱带吸收强度明显增强,反映癌细胞内DNA相对含量增加;位于970cm^-1附近的ν_s,PO₃^{-谱带强度增加,提示细胞中磷酸化蛋白含量增加.而胶原蛋白的特征谱带强度减弱,说明其相对含量减少.研究证明,红外光谱可在分子水平上揭示乳腺肿瘤的特征.}     

中红外光纤技术研究胃正常和肿瘤组织及其原位、在体临床应用

采用中红外光纤衰减全反射光谱法研究胃组织样品, 以48个病人的90个胃组织的红外光谱, 包括32个正常和58个肿瘤组织样品. 肿瘤光谱的特征通常表现在CH和C=O峰的消失, 酰胺I带以及接近1545 cm^&#8722;1的弱的酰胺II带向低波数位移, 1450 cm^&#8722;1峰强度下降并一般弱于1400 cm^&#8722;1峰. 减谱结果表明正常和肿瘤组织的酰胺I带和酰胺II带在峰位和相对强度方面有着较大的差别. 统计分析结果证实了这一结论. 结果表明中红外光纤技术提供了胃肿瘤组织的信息, 能够用来区分正常和肿瘤组织. 实现了肿瘤的在体原位检测, 在手术室旁对新鲜离体样品以及手术过程中在体原位检测恶性肿瘤的结果同对体外液氮冰冻样品和病理检测所得到的结论一致, 这一新结果成为临床应用的基础.     

傅里叶变换红外光谱鉴别正常和良恶性乳腺组织

应用傅立叶变换红外光谱及衰减全反射法, 检测乳腺手术中切除的四种新鲜离体乳腺组织77例,包括正常乳腺组织18例,乳腺增生13例,乳腺纤维腺瘤21例,乳腺癌25例. 用方差分析和秩和检验的方法比较上述四类乳腺组织红外光谱各谱带的峰位、相对峰强及半高宽结果表明：与蛋白、脂质、糖类与核酸相关的谱带在上述四种不同类型乳腺组织之间均存在高度的统计学差异（P<0.05）. 因此,应用FTIR（Fourier Transform Infrared Spectroscopy）可以区分正常乳腺组织、乳腺增生、乳腺纤维腺瘤以及乳腺癌四种乳腺组织,这将为今后在手术中运用原位在体FTIR指导外科医生进行精准手术奠定基础.     

生物滤池中生物膜和出水悬浮物的元素分析和红外光谱比较

对生物滤池中不同高度的生物膜和出水悬浮物的碳氢氮三元素和红外光谱进行了分析比较.元素分析结果表明,悬浮物的无机成份比生物膜高.悬浮物和生物膜的红外吸收光谱图主要由蛋白质的吸收带、碳水化合物的吸收带组成.1655 cm-1处的吸收峰为酰胺Ⅰ带,是C=O的伸缩振动,1542 cm-1的吸收峰是酰胺Ⅱ带,是N-H的弯曲振动和C-N的伸缩振动,1240 cm-1是酰胺Ⅲ带,是C-N的伸缩振动和N-H的弯曲振动引起的.1460 cm-1处的吸收峰为CH3和CH2的弯曲振动峰.悬浮物的蛋白质特征峰强度比生物膜低,而1050cm-1处的吸收峰强度比生物膜大.     

傅里叶变换红外光谱诊断地中海贫血症

为建立简单快速的地中海贫血诊断方法,本研究探讨了以傅里叶变换红外光谱结合水平衰减全反射(FTIR-HATR)技术在地中海贫血诊断中的制样方法及光谱的数据处理方法.在制样预处理中,通过对样品进行稀释并干燥成膜消除水分子对光谱吸收干扰,保持ATR光谱中各波长对样品的穿透深度一致.结果表明,当1652 cm-1吸收度小于1.5时(即透射率T小于4%时),各波峰强度与血红蛋白浓度呈良好的线性关系(r>0.995)及实验重复性(RSD<4%).在数据处理上,改进的相对强度方法用于800～1780 cm-1和2480～3600 cm-1区间的分析.通过与常规的傅里叶去卷积谱及差谱方法相比,本方法可消除样品浓度所带来的影响因素,灵敏地揭示群体数据中组分与结构在不同组间的显著差异,如1638 cm-1处重叠的蛋白二级结构峰,1172 cm-1、1440 cm-1表征脂类物质的吸收峰,1064 cm-1表征磷酸化合物峰位及表征SH的2553 cm-1附近的吸收峰在正常组与地中海贫血组间存在显著差异.从而避免了几个峰位的相对强度所反映的信息不足及选择参比峰的困扰,对揭示整体的差异变化规律有着重要的作用.     

松杉灵芝不同部位的红外光谱分析研究

采用红外光谱三级鉴定法对松杉灵芝菌盖、表皮、菌柄、子实体不同部位的红外光谱图进行了整体分析。结果表明:松杉灵芝的各部位均含萜类、甾醇类、氨基酸、多肽、蛋白质和糖苷类等物质。在松杉灵芝的一维红外光谱中,菌盖的1 649cm-1峰的相对强度明显比表皮、菌柄和子实体强,说明菌盖中所含的氨基酸、多肽、蛋白质物质的量比其它部位高;在二阶导数谱中,四者在1 720~1 600cm-1范围内峰形差别较大,进一步说明松杉灵芝不同部位所含氨基酸、多肽、蛋白质物质不一致;而二维相关红外光谱中,各部位自动峰的数目、峰位置和峰相对强度都有所不同,可推断松杉灵芝各部位本身所含的糖苷类物质是不一致的。     

天花粉蛋白的化学 Ⅵ.用激光拉曼光谱研究天花粉蛋白的二级结构

由天花粉蛋白的水和重水溶液的激光拉曼光谱,测得酰胺Ⅲ谱带1240cm~(-1)和酰胺I谱带1632,1660cm~(-1)对CH_2弯曲模式1448cm~(-1)的强度比值。按Lippert等建立的方程组作定量计算,求得天花粉蛋白的二级结构含量为α-螺旋43.5％,β-折叠31.3％和无序25.2％,它们与4 分辨率天花粉蛋白单晶X射线衍射法的结果相一致。同时,研究了上述溶液的冻干粉状固体的二级结构,经过冻干,使其中约10％的β-折叠转变成无序构象,而α-螺旋含量无明显变化。在水溶液中,由测得的I_(850)/I_(830)比值计算,天花粉蛋白中的酪氨酸残基约有80％呈“暴露式”。     

Upregulated plasma and urinary levels of nucleosides as biological markers in the diagnosis of primary gallbladder cancer

We first detected aberrant nucleoside levels in the plasma, urine, bile, and tissues from cases and controls to explore them as biomarkers in the diagnosis of gallbladder cancer. Reversed‐phase high‐performance liquid chromatography was used to assess the levels of ten nucleosides in these samples from gallbladder cancer patients, gallstone patients, and healthy controls. Plasma and urine samples were collected from patients with gallbladder cancer (n = 202), patients with gallstones (n = 203), and healthy controls (n = 205); bile and tissue samples were collected from 91 gallbladder cancer patients, 93 gallstone patients; and 90 were donated after cardiac death. Of the ten nucleosides analyzed, eight urinary nucleosides, five plasma nucleosides, three bile nucleosides, and one tissue nucleoside were significantly upregulated in the gallbladder cancer patients compared to control groups (p < 0.05). Among these upregulated nucleosides, the sensitivity, specificity, and accuracy of urinary nucleosides in the diagnosis of gallbladder cancer patients were 89.4, 97.1, and 95.7%, respectively, those of plasma nucleosides were 91.2, 95.6, and 94.2%, respectively, those of bile nucleosides were 95.3, 96.4, and 95.1%, respectively, and those of tissue nucleosides were 86.2, 93.8, and 92.6%, respectively. These results suggest that nucleosides may be as useful as biological markers for gallbladder cancer.     

活体小鼠耳朵的拉曼成像方法研究

利用扫描技术获取活体小鼠耳朵组织不同深度的微区拉曼光谱,选取分别归属于血糖、脂类、血红蛋白、蛋白质分子结构的物质的特征谱带1125,1300,1549和1660 cm"1进行峰面积计算,利用这些数据重建二维三维拉曼光谱图像。图像清晰显示了不同物质在活体组织中空间分布情况。实验表明,活体拉曼成像技术可以成为活体研究的新手段。     

Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

The application of molecular spectroscopy inthe biological fields is more and more extensive.Recently vibrational spectroscopy, including FTIRATR Optic Fibers[1—3], FT-IR microspectroscopy[4—6],FT-Raman[7,8] and near IR spectroscopic[9] methods,was used…     

Negative effect of Ni on PtHY in n-pentane isomerization evidenced by IR and ESR studies

Ni/PtHY with different Ni loadings was prepared by impregnating HY with hexachloroplatinic acid solution and Ni2+/N,N-dimethylformamide solution. An increase in the Ni loading decreased the crystallinity, specific surface area and meso-micropores of the catalysts. Ni interacted with hydroxyl groups to produce IR absorption bands at 3740-3500 cm-1. Increasing Ni loadings resulted in a decrease in the intensities of the broad bands at 3730-3500 cm-1 and the sharp band at 3740 cm-1 with simultaneous development of new absorbance band at 3700 cm-1 that was attributed to (-OH)Ni. The acidity of the samples did not significantly change with Ni loadings up to 1.0 wt%, which indicated that Ni mostly interacts with non-acidic silanol groups (terminal- and structural-defect OH groups). The presence of Ni decreased the activity of PtHY toward the isomerization of n-pentane because of a decrease in the number of active protonic-acid sites that formed from molecular hydrogen. IR and ESR studies confirmed that Pt facilitated the formation of protonic-acid sites from molecular hydrogen, whereas Ni, even when combined with Pt, didn’t exhibit such ability. The absence of protonic-acid sites from molecular hydrogen significantly decreased the yield of iso-pentane and markedly increased the cracking products.     

基于稳健统计的新鲜乳腺组织拉曼光谱分析

采用便携式拉曼光谱仪对新鲜乳腺正常组织、良性组织和恶性组织进行检测,通过稳健统计方法对拉曼光谱数据进行分析处理,建立乳腺组织拉曼光谱标准图谱,根据标准图谱特征峰归纳3类组织的主要区别和特征.在3类乳腺组织中,正常组织有明显的脂类特征峰(1078,1297,1437,1653,1746 cm-1),而在良性和恶性组织中则出现了较明显的蛋白特征峰(1259,1530,1650 cm-1),正常、良性和恶性组织的主要区别集中在1340和1534 cm-1处,应归属为蛋白和类胡萝卜素,这一结果并不能由经典统计方法得出.基于稳健统计建立的新鲜乳腺组织拉曼光谱标准图谱为构建数学模型来鉴别乳腺病灶的性质奠定了基础.     

Distinguishing malignant from normal stomach tissues and its <Emphasis Type="Italic">in vivo,in situ</Emphasis> measurement in operating process using FTIR Fiber-Optic techniques

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 48 patients, including 32 normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 1545 cm^-1, a shift of the amide I band to lower wave number, a decrease in the ∼1450 cm^-1 peak to less than the ∼ 1400 cm^-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N², which is the basis for the clinical application.     

High-wavenumber FT-Raman spectroscopy for in vivo and ex vivo measurements of breast cancer

The identification of normal and cancer breast tissue of rats was investigated using high-frequency (HF) FT-Raman spectroscopy with a near-infrared excitation source on in vivo and ex vivo measurements. Significant differences in the Raman intensities of prominent Raman bands of lipids and proteins structures (2,800?C3,100?cm^?1) as well as in the broad band of water (3,100?C3,550?cm^?1) were observed in mean normal and cancer tissue spectra. The multivariate statistical analysis methods of principal components analysis (PCA) and linear discriminant analysis (LDA) were performed on all high-frequency Raman spectra of normal and cancer tissues. LDA results with the leave-one-out cross-validation option yielded a discrimination accuracy of 77.2, 83.3, and 100% for in vivo transcutaneous, in vivo skin-removed, and ex vivo biopsy HF Raman spectra. Despite the lower discrimination value for the in vivo transcutaneous measurements, which could be explained by the breathing movement and skin influences, our results showed good accuracy in discriminating between normal and cancer breast tissue samples. To support this, the calculated integration areas from the receiver-operating characteristic (ROC) curve yielded 0.86, 0.94, and 1.0 for in vivo transcutaneous, in vivo skin-removed, and ex vivo biopsy measurements, respectively. The feasibility of using HF Raman spectroscopy as a clinical diagnostic tool for breast cancer detection and monitoring is due to no interfering contribution from the optical fiber in the HF Raman region, the shorter acquisition time due to a more intense signal in the HF Raman region, and the ability to distinguish between normal and cancerous tissues.     

Infrared spectroscopy of polycyclic aromatic hydrocarbon cations. 1. Matrix-isolated naphthalene and perdeuterated naphthalene

Ionized polycyclic aromatic hydrocarbons (PAHs) are thought to constitute an important component of the interstellar medium. Despite this fact, the infrared spectroscopic properties of ionized PAHs are almost unknown. The results we present here derive from our ongoing spectroscopic study of matrix isolated PAH ions and include the spectra of the naphthalene cation, C10H8+, and its fully deuterated analog, C10D8+, between 4000 and 200 cm-1. Ions are generated in situ Lyman-alpha photoionization of the neutral precursor. Bands of the C10H8+ ion are observed at 1525.7, 1518.8, 1400.9, 1218.0, 1216.9, 1214.9, 1023.2, and 758.7 cm-1. Positions and relative intensities of these bands agree well with those in the available literature. The 758.7 cm-1 band has not previously been reported. C10D8+ ion bands appear at 1466.2, 1463.8, 1379.4, 1373.8, 1077.3, 1075.4, and 1063.1 cm-1. Compared to the analogous modes in the neutral molecule, the intensities of the cation's CC modes are enhanced by an order of magnitude, while CH modes are depressed by this same factor. Integrated absorption intensities are calculated for the strongest bands of C10H8 and for the observed bands of C10H8+. Absolute intensities derived for the naphthalene cation differ from earlier experimental results by a factor of approximately 50, and from theoretical predictions by a factor of approximately 300. Reasons for these discrepancies and from the astronomical implications of PAH cation spectra are discussed.     

Raman study of the hexafluoroaluminate ion in solid and molten FLINAK

Raman spectra have been obtained for matrix-isolated AlF6(3-) in an LiF/NaF/KF (FLINAK) eutectic mixture. Three Raman bands characteristic of the hexafluoroaluminate ion were identified in the solids formed from FLINAK melts which contained small amounts (5-11 mol%) of either AlF3 or Na3AlF6. The three allowed Raman-active bands of the matrix-isolated octahedral complex ion, nu 1(A1g), nu 2(Eg), and nu 5(F2g), were observed at 560.5, 380, and 325 cm-1, respectively, for the solid sample at 25 degrees C. Wavenumbers and relative intensities were similar to those of Na3AlF6 (cryolite), K3AlF6, and K2NaAlF6 (elpasolite) and other crystals known to contain discrete, octahedral AlF6(3-) ions. Peak positions, half-widths, and relative intensities for the bands were measured for samples at temperatures different from room temperature through the melting transition and into the molten state. The transition from high-temperature solid to molten salt at about 455 degrees C occurred gradually without perceptible change in the peak positions, half-widths, or relative intensities. For a sample in molten FLINAK at 455 degrees C, the nu 1(A1g), nu 2(Eg), and nu 5(F2g) modes of the AlF6(3-) ion were observed at 542, 365, and 324 cm-1, respectively. Raman depolarization experiments were consistent with these assignments, and the low value of the depolarization ratio of the nu 1(A1g) mode at 542 cm-1 indicated that the sample was molten above 455 degrees C. Differential thermal analysis also indicated that the FLINAK samples melted at about 455 degrees C. Raman measurements were performed for samples at temperatures from 25 to 600 degrees C in a silver dish, on a hot stage, in an argon-filled atmosphere, under a microscope. Additional Raman experiments were performed on samples at temperatures from 25 to 750 degrees C in a conventional graphite windowless cell, in an argon-filled quartz tube, in a standard furnace. Over the concentration range 4.8-11 mol% AlF3 (CR 23-8.0) in FLINAK, only bands due to the AlF6(3-) ion were detected. There was no evidence to support the presence of other aluminum complexes in these melts.