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Type I collagen D-spacing in fibril bundles of dermis, tendon, and bone: bridging between nano- and micro-level tissue hierarchy.

ABSTRACT: Fibrillar collagens in connective tissues are organized into complex and diverse hierarchical networks. In dermis, bone, and tendon, one common phenomenon at the micrometer scale is the organization of fibrils into bundles. Previously, we have reported that collagen fibrils in these tissues exhibit a 10 nm width distribution of D-spacing values. This study expands the observation to a higher hierarchical level by examining fibril D-spacing distribution in relation to the bundle organization. We used atomic force microscopy imaging and two-dimensional fast Fourier transform analysis to investigate dermis, tendon, and bone tissues. We found that, in each tissue type, collagen fibril D-spacings within a single bundle were nearly identical and frequently differ by less than 1 nm. The full 10 nm range in D-spacing values arises from different values found in different bundles. The similarity in D-spacing was observed to persist for up to 40 ?m in bundle length and width. A nested mixed model analysis of variance examining 107 bundles and 1710 fibrils from dermis, tendon, and bone indicated that fibril D-spacing differences arise primarily at the bundle level (?76%), independent of species or tissue types.

SUBMITTER: Fang M

PROVIDER: S-EPMC3508361 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Type I collagen D-spacing in fibril bundles of dermis, tendon, and bone: bridging between nano- and micro-level tissue hierarchy.

Fang Ming M Goldstein Elizabeth L EL Turner A Simon AS Les Clifford M CM Orr Bradford G BG Fisher Gary J GJ Welch Kathleen B KB Rothman Edward D ED Banaszak Holl Mark M MM

ACS nano 20121022 11

Fibrillar collagens in connective tissues are organized into complex and diverse hierarchical networks. In dermis, bone, and tendon, one common phenomenon at the micrometer scale is the organization of fibrils into bundles. Previously, we have reported that collagen fibrils in these tissues exhibit a 10 nm width distribution of D-spacing values. This study expands the observation to a higher hierarchical level by examining fibril D-spacing distribution in relation to the bundle organization. We ...[more]

PMID: 23083115

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Type I collagen D-spacing in fibril bundles of dermis, tendon, and bone: bridging between nano- and micro-level tissue hierarchy.

Publications

Type I collagen D-spacing in fibril bundles of dermis, tendon, and bone: bridging between nano- and micro-level tissue hierarchy.

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