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Multiscale alterations in bone matrix quality increased fragility in steroid induced osteoporosis.

Karunaratne A, Xi L, Bentley L, Sykes D, Boyde A, Esapa CT, Terrill NJ, Brown SD, Cox RD, Thakker RV, Gupta HS - Bone (2015)

Bottom Line: We measure the deformation of the mineralized collagen fibrils, and the nano-mechanical parameters including effective fibril modulus and fibril to tissue strain ratio.A significant reduction (51%) of fibril modulus was found in Crh(-120/+) mice.We also find a much larger fibril strain/tissue strain ratio in Crh(-120/+) mice (~1.5) compared to the wild-type mice (~0.5), indicative of a lowered mechanical competence at the nanoscale.

View Article: PubMed Central - PubMed

Affiliation: Queen Mary University of London, School of Engineering and Material Science, Mile End Road, London E1 4NS, UK. Electronic address: a.karunaratne@imperial.ac.uk.

No MeSH data available.


Related in: MedlinePlus

Quantitative backscattered scanning electron microscopy. (A) Bone mineral density distribution (BMDD) was produced for WT (black) Crh− 120/+ non-haloes (light gray) and Crh− 120/+ halo (dark gray). (B, C) Camean (representing average mineral content) and FWHM (representing local variation of mineral content) calculated from BMDD and plotted for WT (black) and Crh− 120/+ non-haloes (gray) and halos (dark gray). Errors shown are standard deviations. One way ANOVA test results showed three groups were significantly different for Camean and FWHM measurements. The post-hoc test (Tukey HSD test) was performed subsequently to identify which of the pairs of treatments are significantly different from each other. Pair-wise brackets denote statistical significance (**p < 0.01, ***p < 0.001, ns: not significant).
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f0010: Quantitative backscattered scanning electron microscopy. (A) Bone mineral density distribution (BMDD) was produced for WT (black) Crh− 120/+ non-haloes (light gray) and Crh− 120/+ halo (dark gray). (B, C) Camean (representing average mineral content) and FWHM (representing local variation of mineral content) calculated from BMDD and plotted for WT (black) and Crh− 120/+ non-haloes (gray) and halos (dark gray). Errors shown are standard deviations. One way ANOVA test results showed three groups were significantly different for Camean and FWHM measurements. The post-hoc test (Tukey HSD test) was performed subsequently to identify which of the pairs of treatments are significantly different from each other. Pair-wise brackets denote statistical significance (**p < 0.01, ***p < 0.001, ns: not significant).

Mentions: Bone mineralization density distribution (BMDDs) histograms (Fig. 2A) were plotted for Crh− 120/+ and WT femoral transverse cross-sections. Since we observed very distinct intra-tissue (regions surrounded by the localized cement lines) variation of mineralization on the Crh− 120/+ mice femora as reported above, both regions (Fig. 1Bi and ii) were used separately for quantitative BSE analysis. Crh− 120/+ mice showed a lowered average mineral content compared to WT (Fig. 1B). Mean calcium weight percentage (Camean) was lowest at regions (area surrounded by the cement lines) near the cavities in Crh− 120/+ mice (27.06 ± 1.18 S.D. (Fig. 2B), and significantly greater in the cortical periosteum (p < 0.01) at the regions away from cavities (28.44 ± 0.84 S.D.) (Fig. 1Bii). WT mice (30.32% ± 1.09 S.D.) had significantly higher (p < 0.01 for both WT vs. regions near and away from cavities in Crh− 120/+ mice) Camean compared to Crh− 120/+ mice. The homogeneity of tissue-level mineralization (FWHM) was highest at regions around cavities (6.43 ± 1.30 S.D.) in Crh− 120/+ mice (Fig. 2C), and substantially lower in regions near the periosteal surfaces (4.63 ± 0.73 S.D.) away from the cavities. In contrast to Crh− 120/+ mice bones, WT mice had significantly lower (p < 0.01) FWHM (3.80 ± 1.02 S.D.).


Multiscale alterations in bone matrix quality increased fragility in steroid induced osteoporosis.

Karunaratne A, Xi L, Bentley L, Sykes D, Boyde A, Esapa CT, Terrill NJ, Brown SD, Cox RD, Thakker RV, Gupta HS - Bone (2015)

Quantitative backscattered scanning electron microscopy. (A) Bone mineral density distribution (BMDD) was produced for WT (black) Crh− 120/+ non-haloes (light gray) and Crh− 120/+ halo (dark gray). (B, C) Camean (representing average mineral content) and FWHM (representing local variation of mineral content) calculated from BMDD and plotted for WT (black) and Crh− 120/+ non-haloes (gray) and halos (dark gray). Errors shown are standard deviations. One way ANOVA test results showed three groups were significantly different for Camean and FWHM measurements. The post-hoc test (Tukey HSD test) was performed subsequently to identify which of the pairs of treatments are significantly different from each other. Pair-wise brackets denote statistical significance (**p < 0.01, ***p < 0.001, ns: not significant).
© Copyright Policy - CC BY
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4764652&req=5

f0010: Quantitative backscattered scanning electron microscopy. (A) Bone mineral density distribution (BMDD) was produced for WT (black) Crh− 120/+ non-haloes (light gray) and Crh− 120/+ halo (dark gray). (B, C) Camean (representing average mineral content) and FWHM (representing local variation of mineral content) calculated from BMDD and plotted for WT (black) and Crh− 120/+ non-haloes (gray) and halos (dark gray). Errors shown are standard deviations. One way ANOVA test results showed three groups were significantly different for Camean and FWHM measurements. The post-hoc test (Tukey HSD test) was performed subsequently to identify which of the pairs of treatments are significantly different from each other. Pair-wise brackets denote statistical significance (**p < 0.01, ***p < 0.001, ns: not significant).
Mentions: Bone mineralization density distribution (BMDDs) histograms (Fig. 2A) were plotted for Crh− 120/+ and WT femoral transverse cross-sections. Since we observed very distinct intra-tissue (regions surrounded by the localized cement lines) variation of mineralization on the Crh− 120/+ mice femora as reported above, both regions (Fig. 1Bi and ii) were used separately for quantitative BSE analysis. Crh− 120/+ mice showed a lowered average mineral content compared to WT (Fig. 1B). Mean calcium weight percentage (Camean) was lowest at regions (area surrounded by the cement lines) near the cavities in Crh− 120/+ mice (27.06 ± 1.18 S.D. (Fig. 2B), and significantly greater in the cortical periosteum (p < 0.01) at the regions away from cavities (28.44 ± 0.84 S.D.) (Fig. 1Bii). WT mice (30.32% ± 1.09 S.D.) had significantly higher (p < 0.01 for both WT vs. regions near and away from cavities in Crh− 120/+ mice) Camean compared to Crh− 120/+ mice. The homogeneity of tissue-level mineralization (FWHM) was highest at regions around cavities (6.43 ± 1.30 S.D.) in Crh− 120/+ mice (Fig. 2C), and substantially lower in regions near the periosteal surfaces (4.63 ± 0.73 S.D.) away from the cavities. In contrast to Crh− 120/+ mice bones, WT mice had significantly lower (p < 0.01) FWHM (3.80 ± 1.02 S.D.).

Bottom Line: We measure the deformation of the mineralized collagen fibrils, and the nano-mechanical parameters including effective fibril modulus and fibril to tissue strain ratio.A significant reduction (51%) of fibril modulus was found in Crh(-120/+) mice.We also find a much larger fibril strain/tissue strain ratio in Crh(-120/+) mice (~1.5) compared to the wild-type mice (~0.5), indicative of a lowered mechanical competence at the nanoscale.

View Article: PubMed Central - PubMed

Affiliation: Queen Mary University of London, School of Engineering and Material Science, Mile End Road, London E1 4NS, UK. Electronic address: a.karunaratne@imperial.ac.uk.

No MeSH data available.


Related in: MedlinePlus