pH-induced contrast in viscoelasticity imaging of biopolymers.
pH-induced contrast in viscoelasticity imaging of biopolymers.
复制标题
DOI：
10.1088/0031-9155/54/5/001
复制
发表时间：
2009-03-07
影响因子：
3.5
通讯作者：
Insana MF
中科院分区：
文献类型：
--
作者：
Yapp RD;Insana MF
了解对比机制和识别区别特征是诊断成像发展的核心。这份报告的重点是pH值如何影响生物聚合物的粘弹性，以更好地了解细胞外pH值对乳腺肿瘤弹性成像的影响。已知乳腺肿瘤细胞外pH值降低多达1个pH单位，从而创造了一个危险的环境，增加了细胞突变率和治疗抗性。我们使用明胶水凝胶体模来分离pH对与乳腺基质中的细胞外基质相似的聚合物网络的影响。使用压缩无侧限蠕变和应力松弛测量，我们系统地测量了粘弹性功能敏感的pH值通过时域模型和复模量分析。这些结果被用来确定准静态超声弹性成像pH值的灵敏度。我们发现了一个强大的弹性响应的聚合物网络pH值，使矩阵刚度降低pH值降低，但粘性响应的介质pH值是可以忽略不计的。虽然我们的水凝胶模型中不包括乳腺基质的生理特征，如蛋白聚糖和血管网络，但本研究中的观察结果提供了对胶原基质网络中pH变化特异性粘弹性特征的深入了解。这些观察结果表明，在酸性条件下，乳腺肿瘤伴结缔组织增生常见的大对比度可能会降低，粘弹性特征不太可能提高辨别力。
Understanding contrast mechanisms and identifying discriminating features is at the heart of diagnostic imaging development. This report focuses on how pH influences the viscoelastic properties of biopolymers to better understand the effects of extracellular pH on breast tumour elasticity imaging. Extracellular pH is known to decrease as much as 1 pH unit in breast tumours, thus creating a dangerous environment that increases cellular mutatation rates and therapeutic resistance. We used a gelatin hydrogel phantom to isolate the effects of pH on a polymer network with similarities to the extracellular matrix in breast stroma. Using compressive unconfined creep and stress relaxation measurements, we systematically measured the viscoelastic features sensitive to pH by way of time domain models and complex modulus analysis. These results are used to determine the sensitivity of quasi-static ultrasonic elasticity imaging to pH. We found a strong elastic response of the polymer network to pH, such that the matrix stiffness decreases as pH was reduced, however the viscous response of the medium to pH was negligible. While physiological features of breast stroma such as proteoglycans and vascular networks are not included in our hydrogel model, observations in this study provide insight into viscoelastic features specific to pH changes in the collagenous stromal network. These observations suggest that the large contrast common in breast tumours with desmoplasia may be reduced under acidic conditions, and that viscoelastic features are unlikely to improve discriminability.
登录
查看更多内容
影响因子：
5.6
作者：
Gobeaux, F.;Mosser, G.;Belamie, E.
通讯作者：
Belamie, E.
影响因子：
3.8
作者：
Hitchcock, DI
通讯作者：
Hitchcock, DI
影响因子：
3.9
作者：
Joly-Duhamel, C;Hellio, D;Djabourov, M
通讯作者：
Djabourov, M
影响因子：
--
作者：
Mohanty, B.;Gupta, Amarnath;Bandyopadhyay, S.
通讯作者：
Bandyopadhyay, S.
影响因子：
3.4
作者：
Buehler, Markus J.;Wong, Sophie Y.
通讯作者：
Wong, Sophie Y.