A MIXED PACKING MODEL FOR BONE-COLLAGEN
A MIXED PACKING MODEL FOR BONE-COLLAGEN
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DOI：
10.1007/bf02409497
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发表时间：
1981-01-01
影响因子：
4.2
通讯作者：
LEES, S
中科院分区：
文献类型：
--
作者：
LEES, S
各种各样的物理性质，包括声速，湿和干阶段之间的尺寸变化，各向异性的组织性质，密度，X射线衍射，差示微量热法，介电常数和组成（水，矿物质，有机物含量）的矿化和脱矿组织被用来开发骨胶原的超晶格结构的模型。提出了一种混合模型，其中胶原分子在微纤维内的SLS [段长间距]类型的聚集中登记，并且微纤维根据Hodge-Petruska [HP]方案以D单位步长交错。具有4个或更多个分子/微纤维的正方形堆积模型最适合具有湿胶原分子的有效分子直径的HP方案，并且允许5 nm或更大直径的轴向间隙填充微晶的规则阵列。成年牛骨基质的宏观尺寸变化与胶原超晶格的分子尺寸变化密切匹配。干胶原的有效分子直径为1.09 nm，湿骨胶原的有效分子直径为1.42-1.45 nm。湿骨胶原分子的水层厚度为0.16 nm。骨胶原分子中的水分布在5个区域，与肌腱胶原分子中的情况非常相似。隐藏的水，0.10克水/干燥胶原的制度I和II，是在三螺旋。胶原蛋白分子中结合的外部水提供了高度结构化的胶原蛋白分子和分子间介质之间的过渡。结合在矿化骨胶原分子中的水少于脱矿骨基质中的水。对于成年牛皮质骨，25%体积是水，32%干燥有机物，43%矿物质; 28%体积的矿物质是轴向间隙填充物，58%径向纤维内和14%径向纤维外。
A wide variety of physical properties, including sonic velocity, dimensional changes between wet and dried stages, anisotropy of the tissue properties, density, X-ray diffraction, differential microcalorimetry, dielectric constant and composition (water, mineral, organic content) for the mineralized and demineralized tissue was used to develop a model for the superlattice structure of bone collagen. A mixed model is suggested where the collagen molecules are in register as in SLS [segment-long-spacing] type of aggregation within the microfibril, and the microfibrils are staggered in D unit steps according to the Hodge-Petruska [HP] scheme. A square packing model with 4 or more molecules/microfibril best fits the HP scheme with the effective molecular diameter of the wet collagen molecule, and allows for the regular array of axial gap filling microcrystallites of 5 nm or larger diameter. Macroscopic dimensional changes of adult bovine bone matrix closely match molecular dimensional changes of collagen superlattice. Effective molecular diameter of dry collagen is 1.09 nm and that of wet bone collagen is 1.42-1.45 nm. The water layer of wet bone collagen molecule is 0.16 nm thick. Water in the bone collagen molecule is distributed in 5 regimes much like in the tendon collagen molecule. Hidden water, 0.10 g water/dry collagen of regimes I and II, is within the triple helix. External water incorporated in the collagen molecule provides transition between the highly structured collagen molecule and the intermolecular medium. Water incorporated in the mineralized bone collagen molecule is less than in demineralized bone matrix. For adult bovine cortical bone, 25% by volume is water, 32% dry organic, 43% mineral; 28% by volume of the mineral is axial gap filling, 58% radial intrafibrillar and 14% radial extrafibrillar.