Multinucleated TRAP⁺ OCLs.

<p>The images show sRANKL-treated RAW264.7 cells cultured in direct contact with the samples: (A) HA-LF, (B) HA, (C) LF and (D) cells only, respectively. White arrows indicate large and multinucleated cells positive for tartrate-resistant acid phosphatase (mature OCLs). Scale bar 100 μm.</p

A Step toward Control of the Surface Structure of Biomimetic Hydroxyapatite Nanoparticles: Effect of Carboxylates on the {010} P‑Rich/Ca-Rich Facets Ratio

Two types of biomimetic hydroxyapatite (HA) nanoparticles were prepared by acid–base neutralization reactions, using Ca­(OH)₂ or Ca­(CH₃COO)₂ as a calcium source, to evaluate the effect of acetate anions on particle formation. High-resolution transmission electron microscopy observations provided evidence that in both cases nanoparticles are elongated along the <i>c</i>-axis, but to a more limited extent when prepared in the presence of acetates, and are mainly limited by {010} facets. IR spectra of nanoparticles containing adsorbed CO revealed that the actual termination of these are both of the {010}_Ca-rich and {010}_P-rich type, the latter being significantly more abundant for HA nanoparticles grown in the medium containing CH₃COO^– species. Moreover, these nanoparticles appeared to be more sensitive toward aggregative stacking by thermal treatment, resulting in a significant decrease in specific surface area, while retaining the size of primary particles

Samples identification.

<p>Labelling of the samples, weight percentage (wt%) of LF loaded onto HA and LF and HA concentration (μg/ml) of the samples tested in the study.</p><p>Samples identification.</p

OBs viability and apoptosis.

<p>(A) shows the percentage of live OBs respect to the total cells counted and (B) shows the percentage of apoptotic OBs respect to the total cells counted. Mean and standard error (n = 3) represented as the percentage of the total counted cells, after 7 and 14 days of culture in direct contact with all the tested samples. Statistical significant differences among the samples are indicated in both graphs: *p≤0.05. (C) Different examples of nuclear fragmentation in OBs stained with DAPI are indicated with red arrows. Scale bar 50 μm.</p

Co-cultured OCLs gene expression analysis.

<p>Relative quantification (2^-ΔΔCt) of gene expression after 7 days of OCLs co-cultured with OBs grown in direct contact with all the tested samples. The graphs show the average and standard error of the technical triplicate of Oscar, Itgβ3 and CtsK, respect to the expression of the cells only, used as a control. Statistical significant difference among the samples is indicated in the graph: **p≤0.01.</p

OCLs gene expression analysis.

<p>Relative quantification (2^-ΔΔCt) of gene expression after 7 days of OCLs cultured in direct contact with all the tested samples. Average and standard error of the technical triplicate of Oscar, Itgβ3 and CtsK, respect to the expression of the cells only, were indicated. Statistical significant difference among the samples is indicated in the graph: *p≤0.05.</p

OBs gene expression analysis.

<p>(a) and (c) Relative quantification (2^-ΔΔCt) of gene expression after 7 and (b) and (d) 14 days of OBs cultured in direct contact with all the tested samples. The graph shows the average and standard error of the technical triplicate of Osterix and IBSP, respect to the expression of the cells only, used as a control. Statistical significant differences among the samples are indicated in the graphs: *p≤0.05 and ***p≤0.001.</p

Calcium Phosphates from Fishery Byproducts as a Booster of the Sun Protection Factor in Sunscreens

Calcium phosphates (CaPs) have been recently proposed as a bio- and eco-compatible alternative to UV filters in sunscreens, which are in the spotlight for being associated with health risks for both people and the environment. Here, natural CaPs extracted from fish bones have been tested as a booster of the sun protection factor (SPF), that is, as material working in synergy with UV filters to increase sunscreen UV-shielding efficiency, in combination with three of the most used UV filters, namely, octocrylene (OCR), octinoxate, and padimate-O, at different concentrations (10.0 and 20.0 wt %). The material obtained by calcination at 800 °C (CaP-N) was also enriched with Zn (CaP-Zn) or Mn (CaP-Mn) in an attempt to increase its SPF-boosting abilities. CaP-N and CaP-Zn consisted of a biphasic mixture of hydroxyapatite and beta tricalcium phosphate, while CaP-Mn presented a small quantity of Mn oxides. CaP-N was the most effective at increasing the SPF of the final emulsions, doubling the SPF of the formulation containing 20.0 wt % of OCR from 40.6 to 80.8. The results show that these CaPs, produced according to a circular economy approach, can be used as effective SPF boosters to decrease the concentration of UV filters used in sunscreen, while retaining high SPF values

OPG/RANKL ratio in OBs/OCLs co-culture.

<p>In the graph is reported the ratio of the soluble factors measured by ELISA kit. Mean and standard error of three replicates are shown. Statistical significant differences among the samples are indicated in the graph: *p≤0.05.</p

Surface Hydration and Cationic Sites of Nanohydroxyapatites with Amorphous or Crystalline Surfaces: A Comparative Study

This paper is an extension of previous work devoted to the characterization of platelet-like hydroxyapatite (HA) nanoparticles constituted by a crystalline core coated by an amorphous surface layer 1−2 nm thick (Bertinetti et al. J. Phys. Chem. C. 2007, 111, 4027−4035). By increasing the preparation temperature, the platelet morphology was retained but HA nanoparticles exhibited a higher degree of crystallinity (evaluated by X-ray diffractometry). High-resolution transmission electron microscopy revealed that, in this case, the crystalline order was extended up to the particles’ surfaces, which were of the (010), (100), and (001) types. IR spectroscopy was used to investigate the surface hydration of both materials, in terms of adsorbed H2O molecules and surface hydroxy groups, as well as the Lewis acidity of surface cations, by removing water and adsorbing CO. For both features, strong similarities between amorphous and crystalline surfaces were found