Christov A M, Liu L, Lowe S, Icton C, Dunmore-Buyze J, Boughner D R, Dai E, Lucas A
J.P. Robarts Research Institute, University of Western Ontario, London, Canada.
Photochem Photobiol. 1999 Mar;69(3):382-9. doi: 10.1562/0031-8655(1999)069<0382:lifrot>2.3.co;2.
Reconstruction and replacement of heart valves with grafts fro pig tissue is a common procedure. However, bioprosthetic valves wear out in a shorter time span than mechanical valves. Bioprosthetic valve structure may contribute to degenerative changes that lead to valve failure. There is, at present, no method to examine the structure of a tissue valve prior to implant. Laser-induced fluorescence (LIF) of natural fluorophores is an elegant method developed for the detection of tumors, dermal lesions and atherosclerosis. We have studied LIF as a potential diagnostic technique for analysis of valvular tissue. Using excimer laser excitation, we examined natural fluorescence recorded from porcine aortic, mitral and pulmonary valves. All three valve outflow surface tissue layers are less fluorescent at 390-450 nm than the inflow layers. Immunohistochemical analysis of collagen I and elastin content in inflow and outflow surface layers of all three valves correlated well with LIF intensities and dI/d lambda values at selected wavelengths. In conclusion, the differences observed in emitted LIF from valve surface layers are found to correlate well with diversity in the structural protein content. The LIF spectroscopic measurements may provide an appropriate tool for examination of tissue valve structure prior to use for implantation.
用猪组织移植物重建和置换心脏瓣膜是一种常见的手术。然而，生物人工心脏瓣膜比机械瓣膜磨损的时间更短。生物人工心脏瓣膜的结构可能会导致退行性变化，进而导致瓣膜失效。目前，在植入前没有方法可以检查组织瓣膜的结构。天然荧光团的激光诱导荧光（LIF）是一种用于检测肿瘤、皮肤病变和动脉粥样硬化的精妙方法。我们研究了LIF作为分析瓣膜组织的潜在诊断技术。使用准分子激光激发，我们检测了从猪主动脉瓣、二尖瓣和肺动脉瓣记录到的天然荧光。所有三个瓣膜流出表面组织层在390 - 450纳米处的荧光都比流入层弱。对所有三个瓣膜流入和流出表面层中I型胶原蛋白和弹性蛋白含量的免疫组织化学分析与选定波长下的LIF强度和dI/dλ值密切相关。总之，发现从瓣膜表面层发射的LIF中观察到的差异与结构蛋白含量的差异密切相关。LIF光谱测量可能为在用于植入前检查组织瓣膜结构提供一种合适的工具。
