Ex vivo quantification of the time course of contractile loading of the porcine lens capsule after cataract-like surgery
Ex vivo quantification of the time course of contractile loading of the porcine lens capsule after cataract-like surgery
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DOI：
10.1016/j.exer.2009.07.013
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发表时间：
2009-12-01
影响因子：
3.4
通讯作者：
Humphrey, J. D.
中科院分区：
文献类型：
--
作者：
Pedrigi, R. M.;Dziezyc, J.;Humphrey, J. D.
白内障手术是一种侵入性手术，其用平坦的假体装置替换准球形的天然透镜纤维，这最初降低了残余透镜囊内的机械应力，并且最终导致囊围绕植入物收缩。虽然几何形状的变化以前已经量化，但对与这种收缩相关的载荷知之甚少。我们提出了一种新的实验培养装置，以量化离体的时间过程中的张力增加的收缩透镜囊后，白内障样手术。结果表明，收缩在大约一个月内达到稳定状态，平均张力为1.45 mN/mm，柯西（真实）应力为13.4 kPa。与新鲜的透镜囊相比，在后培养中也发现α-平滑肌肌动蛋白（α-SMA）的显著增加，从而表明转分化的透镜上皮细胞（LEC）调节收缩。量化收缩透镜囊所施加的载荷对于评估植入物/囊相互作用和植入物体内稳定性非常重要。由于晶状体囊的收缩可能部分受到晶状体上皮细胞试图恢复其天然机械环境的调节，我们的研究结果进一步表明了手术后通常观察到的囊结构长期错误变化的可能机制。(C)2009爱思唯尔有限公司保留所有权利。
Cataract surgery is an invasive procedure that replaces the quasi-spherical native lens fibers with a flat prosthetic device, which initially reduces mechanical stress within the remnant lens capsule and, ultimately, leads to contraction of the capsule about the implant. Although resultant changes in geometry have been quantified previously, little is known about the loads associated with this contraction. We present a novel experimental culture device to quantify ex vivo the time course of increases in tension within the contracting lens capsule after cataract-like surgery. Results demonstrate that contraction reaches steady state within approximately one month with a mean tension of 1.45 mN/mm and Cauchy (true) stress of 13.4 kPa. A significant increase in alpha-smooth muscle actin (alpha-SMA) was also found in post-cultured compared to fresh lens capsules, thus suggesting that transdifferentiated lens epithelial cells (LECs) modulated the contraction. Quantification of loads imparted by the contracting lens capsule is important for assessing implant/capsule interactions and implant stability in vivo. Because contraction of the capsule may be modulated in part by LECs attempting to restore their native mechanical environment, our results further suggest a possible mechanism for the long-term errant changes in capsular structure commonly observed after surgery. (C) 2009 Elsevier Ltd. All rights reserved.