Two discriminant methods, partial least squares-discriminant analysis (PLS-DA) and Fisher's discriminant analysis (FDA), were combined with Fourier transform infrared imaging (FTIRI) to differentiate healthy and osteoarthritic articular cartilage in a canine model. Osteoarthritic cartilage had been developed for up to two years after the anterior cruciate ligament (ACL) transection in one knee. Cartilage specimens were sectioned into 10 μm thickness for FTIRI. A PLS-DA model was developed after spectral pre-processing. All IR spectra extracted from FTIR images were calculated by PLS-DA with the discriminant accuracy of 90%. Prior to FDA, principal component analysis (PCA) was performed to decompose the IR spectral matrix into informative principal component matrices. Based on the di?erent discriminant mechanism, the discriminant accuracy (96%) of PCA-FDA with high convenience was higher than that of PLSDA. No healthy cartilage sample was mis-assigned by these two methods. The above mentioned suggested that both integrated technologies of FTIRI-PLS-DA and, especially, FTIRI-PCA-FDA could become a promising tool for the discrimination of healthy and osteoarthritic cartilage specimen as well as the diagnosis of cartilage lesion at microscopic level. The results of the study would be helpful for better understanding the pathology of osteoarthritics.

福尔马林溶液对于固化关节软骨组织、 防止在长时间测量过程中组织的分解退化起到很好的作用, 但对福尔马林溶液浸泡后软骨组织的结构变化(固化)过程及其胶原纤维各向异性的改变却鲜有研究。 采用傅里叶变换红外光谱显微成像技术与偏振技术相结合的方法, 通过关节软骨内胶原纤维(蛋白)的红外光谱特征吸收峰(Amide Ⅰ, Amide Ⅱ带)的吸光度随福尔马林溶液浸泡时间及偏光角度的变化来研究福尔马林溶液对软骨组织结构即胶原纤维各向异性的影响, 并利用与各向异性方程拟合得到的决定系数(R2)对胶原蛋白纤维各向异性程度进行表征。 研究发现, 关节软骨Amide Ⅰ和Amide Ⅱ带的各向异性随着福尔马林浸泡时间的增长而愈加明显(Amide Ⅰ带变化尤为明显), 说明福尔马林溶液中甲醛分子诱发了胶原蛋白分子新的交联, 最终获得较好的固化效果, 有利于关节软骨的各向异性分析。 本研究将为今后关节软骨样本的制备、 储存及各向异性研究提供参考。

基于关节软骨组织中胶原蛋白的自发荧光特性,对软骨组织的荧光显微检测方法进行研究。首先基于荧光图像的统计处理,揭示健康样本与病变样本的差异。其次基于荧光的偏振敏感特性,利用线性二色性方法揭示了软骨组织存在的荧光各向异性特性,为利用荧光各向异性方法研究生物组织结构奠定基础。与传统的显微方法检测软骨组织的形态和超结构相比,利用荧光特性的荧光显微检测方法具有获取软骨组织结构的能力。本文的研究结果为开辟新的骨关节疾病诊断方法提供基础。