先天性厚甲症-I型患者及正常人指甲的红外光谱对比分析

目的应用傅里叶变换红外光谱(Fourier transform infrared,FTIR)技术和曲线拟合方法,比较先天性厚甲症-I型(PC-1)患者指甲与正常人指甲在红外光谱参数和蛋白质二级结构方面的差异。方法收集来自3个家系的PC-1患者手指甲7例和正常人手指甲10例,FTIR分析采用溴化钾压片方法进行;红外光谱酰胺I带采用PeakFit v4.12软件处理,求取蛋白质各二级结构百分含量。结果在红外光谱波数为3 000~1 000 cm-1的范围内,PC-1患者指甲与正常人指甲的光谱参数,如峰位置、峰强度和峰形状等均存在明显差异;另外,与正常人指甲相比,患者指甲蛋白质二级结构最为显著的变化是α-螺旋的增加和β-折叠的减少,这显示PC-1患者指甲具有更高的稳定性。结论PC-1患者和正常人指甲在光谱参数和蛋白质二级结构方面存在显著的差异,不仅为阐明PC-1的生化机制及其治疗提供了微观结构方面的参考,同时也表明红外光谱技术在研究人类皮肤疾病方面有着好的应用前景。

Comparative FTIR spectra analysis for finger nails of normal donors and patients with type I pachyonychia congenita

Objective To apply Fourier transform infrared （FTIR） spectroscopy technique combined with a curve-fitting method to compare the differences between normal donor and PC-1 patient fingernails in the spectral parameters and secondary structures of protein. Methods Finger nail samples from ten normal donors and seven PC type 1 （PC-1） patients in three pedigrees with PC were collected. Spectral analyses of fingernail samples were accomplished by a Nicolet 6700 FTIR using KBr pellet method. The amide I bands were treated by empolying PeakFitv 4.12 software to obtain the contents of the protein secondary structures. Results In the frequency region 3 000 to 1 000 cm^-1, there are obvious differences between FTIR spectra of them in spectral parameters such as peak location, intensity and band shape etc. Furthermore, compared with normal counterparts, the most prominent discriminating changes in the protein secondary structures of PC-1 nails were an increase of α-helices and decrease of β-sheet.This may suggest a higher stabilization in protein of PC-1 nails. Conclusion The present results not only might provide a new reference on the microstructure for further clarifying of the biochemical pathways of the abnormality of PC nails, but also suggest the potential use of IR spectroscopy technique as a powerful tool for the analysis of skin diseases.