Joshi H M, Woods A K, Smyth E, Gosselink M P, Cunningham C, Lindsey I, Urban J, Jones O M, Vollrath F
Oxford Pelvic Floor Centre, Oxford University Hospitals Trust, Oxford, UK,
Int J Colorectal Dis. 2015 Aug;30(8):1117-22. doi: 10.1007/s00384-015-2222-x. Epub 2015 Apr 29.
It is still an enigma that some patients develop rectal prolapse whilst others with similar risk factors do not. Biomechanical assessment of the skin may provide further insight into the aetiology of this complex condition. Elastin fibres are an abundant and integral part of many extracellular matrices and are especially critical for providing the property of elastic recoil to tissues. The significance of elastin fibres is clearly reflected by the numerous human conditions in which a skin phenotype occurs as a result of elastin fibre abnormalities.
Between January and June 2013, skin specimens were obtained prospectively during surgery on 20 patients with rectal prolapse and 21 patients without prolapse undergoing surgery for other indications. Expression levels of elastin in the skin were measured by Orcein staining, and Image J. Tensile tests were performed using the Zwick Roell device, with custom ceramic clamps. For statistical analysis, Student's t test was used.
Histological analysis of prolapse vs control showed percentage dermal elastin fibres of 9 vs 5.8 % (p = 0.001) in males and 6.5 vs 5.3 % (p = 0.05) in females. Patients with more severe prolapse (external) had a significantly (p = 0.05) higher percentage dermal elastin fibres 6.9 vs 6.1 % than internal prolapse. Young's modulus of patients with prolapse was lower in males (3.3 vs 2.8, p = 0.05) and females (3.1 vs 2.7, p = 0.05).
Patients with prolapse have a higher concentration of elastin fibres in the skin, and these differences are quantitatively demonstrated through mechanical testing. This suggests that the aetiology may be a result of a dysfunction of elastin fibre assembly.
有些患者会发生直肠脱垂，而其他具有相似风险因素的患者却不会，这仍是一个谜。对皮肤进行生物力学评估可能会为这种复杂病症的病因提供进一步的见解。弹性纤维是许多细胞外基质中丰富且不可或缺的一部分，对于赋予组织弹性回缩特性尤为关键。弹性纤维的重要性在众多因弹性纤维异常而出现皮肤表型的人类病症中得到了明显体现。
在2013年1月至6月期间，前瞻性地获取了20例直肠脱垂患者以及21例因其他适应症接受手术的非脱垂患者手术过程中的皮肤标本。通过地衣红染色和Image J测量皮肤中弹性蛋白的表达水平。使用Zwick Roell设备及定制陶瓷夹进行拉伸试验。统计分析采用学生t检验。
脱垂组与对照组的组织学分析显示，男性真皮弹性纤维百分比分别为9%和5.8%（p = 0.001），女性为6.5%和5.3%（p = 0.05）。脱垂更严重（外部脱垂）的患者真皮弹性纤维百分比显著更高（p = 0.05），为6.9%，而内部脱垂患者为6.1%。脱垂患者的杨氏模量在男性中较低（3.3对2.8，p = 0.05），在女性中也较低（3.1对2.7，p = 0.05）。
脱垂患者皮肤中弹性纤维浓度更高，并且这些差异通过力学测试得到了定量证明。这表明病因可能是弹性纤维组装功能障碍的结果。
