Magnetic resonance microscopy of collagen mineralization
Magnetic resonance microscopy of collagen mineralization
复制标题
DOI：
10.1529/biophysj.107.120923
复制
发表时间：
2008-08-15
影响因子：
3.4
通讯作者：
Potter, Kimberlee
中科院分区：
文献类型：
--
作者：
Chesnick, Ingrid E.;Mason, Jeffrey T.;Potter, Kimberlee
一个模型矿化系统进行磁共振显微镜研究如何水质子横向（T-2）弛豫时间和磁化传递比可以应用于监测胶原矿化。在我们的模型系统中，胶原海绵矿化聚合物稳定的无定形碳酸钙。胶原海绵在初始矿化阶段的较低水合和水质子T-2值归因于无定形碳酸钙替换胶原原纤维内的水。到第6天T2值的显著降低（p < 0.001）归因于矿物微晶的出现，其也通过X射线衍射和扫描电子显微镜检测到。在第二阶段，在第6和13天之间，磁共振显微镜的性能出现高原无定形碳酸钙液滴开始聚结内胶原纤维的空间。在第三阶段，在第15天后，无定形矿物相结晶，导致胶原衍射图案的绝对强度降低。我们推测，具有相似胶原含量的胶原海绵的磁化传递比值从对照条的0.25 +/- 0.02增加到第15天的最大值0.31 +/- 0.04（p = 0.03），因为矿物晶体大大降低了胶原原纤维的流动性。
A model mineralizing system was subjected to magnetic resonance microscopy to investigate how water proton transverse (T-2) relaxation times and magnetization transfer ratios can be applied to monitor collagen mineralization. In our model system, a collagen sponge was mineralized with polymer-stabilized amorphous calcium carbonate. The lower hydration and water proton T-2 values of collagen sponges during the initial mineralization phase were attributed to the replacement of the water within the collagen fibrils by amorphous calcium carbonate. The significant reduction in T2 values by day 6 ( p < 0.001) was attributed to the appearance of mineral crystallites, which were also detected by x-ray diffraction and scanning electron microscopy. In the second phase, between days 6 and 13, magnetic resonance microscopy properties appear to plateau as amorphous calcium carbonate droplets began to coalesce within the intra fibrillar space of collagen. In the third phase, after day 15, the amorphous mineral phase crystallized, resulting in a reduction in the absolute intensity of the collagen diffraction pattern. We speculate that magnetization transfer ratio values for collagen sponges, with similar collagen contents, increased from 0.25 +/- 0.02 for control strips to a maximum value of 0.31 +/- 0.04 at day 15 (p = 0.03) because mineral crystals greatly reduce the mobility of the collagen fibrils.