OCLs gene expression analysis.

<p>Relative quantification of gene expression after 7 and 14 days of OCLs grown on Sr-BCs. The graph showed the fold change expression of Oscar, CtsK and Itgβ3 relative to the expression of the OCLs grown on BCs, used as a control. Statistical differences exist for Oscar and CtsK expression between day 7 and day 14 of culture (*p≤0.05; ** p≤ 0.01).</p

OBs gene expression analysis.

<p>Relative quantification of gene expression after 7 and 14 days of OBs grown on Sr-BCs. The graph showed the fold change expression of Osterix, Bglap and IBSP, relative to the expression of the OBs grown on BCs, used as a control.</p

MSCs viability.

<p>Percentage of MSCs viability grown in Sr2% and 5%-BCs compared to the cells grown in BC. Statistical analysis showed no differences among the samples tested and over the experimental time points.</p

MSCs gene expression analysis.

<p>Relative quantification of gene expression after 7 and 14 days of MSCs grown on Sr-BCs. The graph showed the fold change expression of RUNX2 and ALP, relative to the expression of the MSCs grown on BCs, used as a control (*p≤0.05; **p≤0.01).</p

Cells morphology.

<p>The upper level on the panel showed phalloidin staining: in green the cytoplasm of the cells and in blue the nuclei. At 3d, MSCs (A) and OBs (B) were well spread on BC surface exhibiting their characteristic morphology without any difference among each sample; scale bars 200 μm. Image (C) showed a big multinucleate OCLs (*) and groups of undifferentiated monocytes (white arrows); scale bar 50 μm. On the lower level of the panel SEM images are showed: D and E showed the cytoplasmic extension (white arrows) of MSCs and OBs, respectively; scale bars 5 μm. (F) One OCLs grown on BCs surface, exhibiting the typical apical-basal polarised resorbing morphology (yellow arrow); scale bar 10 μm.</p

Ion concentration.

<p>Cumulative Ca²⁺ (A) and Sr²⁺ (B) ion release concentrations from the cements in Dulbecco's modified Eagle's medium and resulting ion concentration (in weight %) in respect to the initial amount of Sr²⁺ in the precursor powders (C). (*p≤0.05; **p≤0.01, ***p≤0.001).</p

OBs viability.

<p>The viability of OBs grown in Sr2% and 5%-BCs were increased compared to the cells grown in BC (Two-way Anova p≤0.0001). Statistical analysis shown significant differences between Sr2%-BC and Sr5%-BC after 3, 7 and 14 days of culture (**p≤0.01; ****p≤0.0001).</p

Magnetic Bioinspired Hybrid Nanostructured Collagen–Hydroxyapatite Scaffolds Supporting Cell Proliferation and Tuning Regenerative Process

A bioinspired mineralization process was applied to develop biomimetic hybrid scaffolds made of (Fe²⁺/Fe³⁺)-doped hydroxyapatite nanocrystals nucleated on self-assembling collagen fibers and endowed with super-paramagnetic properties, minimizing the formation of potentially cytotoxic magnetic phases such as magnetite or other iron oxide phases. Magnetic composites were prepared at different temperatures, and the effect of this parameter on the reaction yield in terms of mineralization degree, morphology, degradation, and magnetization was investigated. The influence of scaffold properties on cells was evaluated by seeding human osteoblast-like cells on magnetic and nonmagnetic materials, and differences in terms of viability, adhesion, and proliferation were studied. The synthesis temperature affects mainly the chemical–physical features of the mineral phase of the composites influencing the degradation, the microstructure, and the magnetization values of the entire scaffold and its biological performance. In vitro investigations indicated the biocompatibility of the materials and that the magnetization of the super-paramagnetic scaffolds, induced applying an external static magnetic field, improved cell proliferation in comparison to the nonmagnetic scaffold

53BP1 assay for genotoxicity assessment of model genotoxicants.

HCT116 cells were exposed to (a) aflatoxin B1, (b) methyl methanesulfonate, (c) etoposide, (d) hydroquinone, (e) taxol, (f) azidothymidine, (g) N-nitroso-N-ethylurea, (h) Di(2ethyl hexyl)phthalate, (i) propyl gallate for 24 h and then fixed or to (j) a 1 Gy X-ray irradiation and then fixed 30 min, 1 h, 1 h 30, 2 h or 24 h after irradiation. Then, the 53BP1 assay results was compared to that of γ-H2AX assay, on cells exposed to 1 Gy X-ray irradiation, 30 min after irradiation (k). All these samples were immunostained for 53BP1 (or γ-H2AX) foci, and foci were counted in each cell nucleus using automated fluorescence microscopy. Depicted are the mean number of foci per cell nucleus ± standard deviation of 3 independent experiments with 5 replicates per experiment (n = 15). Statistical significance: *p#p<0.05, 400 μM vs. 80 μM (MMS) or 12.5 μM, 25 μM or 50 μM vs. 5 μM (taxol).</p

Nanomaterial genotoxicity evaluation using the high-throughput p53-binding protein 1 (53BP1) assay.

Nanomaterial genotoxicity evaluation using the high-throughput p53-binding protein 1 (53BP1) assay.</p