Potentials of Polyphenols in Bone-Implant Devices

Knowledge of bioactive plant-derived polyphenols is growing to such an extent that science interest is looking at development of different applications in regenerative medicine through new and state-of-the-art tissue engineering technologies. Due to their well-established and demonstrated antioxidant and anti-inflammatory beneficial properties, polyphenols have been extensively investigated to the extent that they provide benefits to different pathological conditions, including cardiovascular and bone diseases, neurodegenerative disorders, and cancer. By taking into account the main molecular pathways of polyphenols’ action, we want to focus this chapter on applications of polyphenols in bone-implant devices. In particular, results of polyphenols’ effects on bone cells and tissues following local delivery from innovative biomaterials will be discussed, together with preliminary in vivo tests. Purpose of the dissertation is to provide the reader new insights into knowledge of polyphenols not only regarding the different molecular mechanisms involved in their action but also the biological responses deriving from local applications

Ágape Insípido (a flavourless feast) (performance / workshop)

This performance was given during the Feeding Creativity workshops held at the UAB and Fundació Miró. Ágape Insípido recreates the traditional ceremony of a classic banquet, but transforms it into a new experimental performance ‘banquet’ in which the guests become the protagonists of the action. Starting with a specific situation, the idea is to lead participants towards a state of liminality, which brings with it the possibility of an opening towards new ways of behaving and perceiving reality

New collagen‐coated calcium phosphate synthetic bone filler (Synergoss®): A comparative surface analysis

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Evaluation of Bone Regeneration Efficacy in a Rabbit Model of Femoral Condyles Defect by Polyphenols-Containing Bone Filler

[EN] The purpose of this study was to evaluate the local biological effects and bone regeneration efficacy of a polyphenols-enriched ceramic bone filler. To this end, a test article (NBR_Purple) a biphasic phosphate ceramic plus polyphenols from grape pomace and the same material without polypohenols (NBR_White), were implanted in the medial condyle of the femur bone of rabbits for 56 days. A control article of clinical use (Ostim ®), was implanted as the first control condition. There was a second control by performing the same defect at the same location but without any implanted material (void condition). Histological examination at the end of the test period shows statistically significant improvement of bone regeneration by the polyphenolenriched material over the same material without polyphenols, supporting literature data on the involvement of polyphenol molecules in bone regeneration pathways.Iviglia, G.; Cassinelli, C.; Peris Serra, JL.; Primo Capella, V.; Morra, M. (2020). Evaluation of Bone Regeneration Efficacy in a Rabbit Model of Femoral Condyles Defect by Polyphenols-Containing Bone Filler. Journal of Oral & Maxillofacial Research. 3(3):1-8. https://doi.org/10.31038/JDMR.2020334S183

The incorporation of strontium to improve bone-regeneration ability of mesoporous bioactive glasses

Over the recent years, mesoporous bioactive glasses (MBGs) gained interest as bone regeneration systems, due to their excellent bioactivity and ability to release therapeutic molecules. In order to improve the bone regeneration ability of MBGs, the incorporation of Sr2+ ions, due to its recognized pro-osteogenenic potential, represents a very promising strategy. In this study, MBGs based on the SiO₂⁻CaO system and containing different percentages (2 and 4 mol %) of strontium were prepared by two synthesis methods, in the form of microspheres and nanoparticles. Sr-containing MBGs were characterized by FE-SEM, XRD and N₂ adsorption/desorption analysis. The in vitro bioactivity in SBF resulted excellent. The assessment of fibroblast cell (line L929) viability showed that Sr-containing MBGs were biocompatible both in form of micro- and nanoparticles. The osteogenic response of osteoblast-like SAOS-2 cells was investigated by analysing the expression of GAPDH, COL1a1, RANKL, SPARC, OPG and ALPL genes, as cell differentiation markers. The results indicate that the incorporation of Sr into MBG is beneficial for bone regeneration as promotes a pro-osteogenic effect, paving the way to the design of advanced devices enabled by these nanocarriers also in combination with drug release, for the treatment of bone pathologies, particularly in patients with osteoporosis

Spatiotemporal Imaging of the Acoustic Field Emitted by a Single Copper Nanowire

International audienceThe monochromatic and geometrically anisotropic acoustic field generated by 400 nm and 120 nm diameter copper nanowires simply dropped on a 10 µm silicon membrane is investigated in transmission using three-dimensional time-resolved femtosecond pump-probe experiments. Two pump-probe time-resolved experiments are carried out at the same time on both side of the silicon substrate. In reflection, the first radial breathing mode of the nanowire is excited and detected. In transmission, the longitudinal and shear waves are observed. The longitudinal signal is followed by a monochromatic component associated with the relaxation of the nanowire's first radial breathing mode. Finite Difference Time Domain (FDTD) simulations are performed and accurately reproduce the diffracted field. A shape anisotropy resulting from the large aspect ratio of the nanowire is detected in the acoustic field. The orientation of the underlying nanowires is thus acoustically deduced

Amorphous WO3 as transparent conductive oxide in the near-IR

The demand for transparent conductive films (TCFs) is dramatically increasing. In this work tungsten oxide (WO3-x) is studied as a possible option additional to the existed TCFs. We introduce WO3-x thin films fabricated by a non-reactive magnetron RF-sputtering process at room temperature, followed by thermal annealing in dry air. Films are characterized morphologically, structurally, electrically, optically, and dielectrically. Amorphous WO3-x thin films are shown to be ntype conductive while the transparency extends to the near-IR. By evaluating a figure of merit for transparent-conductive performance and comparing to some most-widely used TCFs, WO3-x turns out to outperform in the near-IR optical range

Evaluation of cytotoxicity and antibacterial activity of a new class of silver citrate-based compounds as endodontic Irrigants

In the present study, the cytotoxicity and the antimicrobial activity of two silver citrate-based irrigant solutions were investigated. Cytotoxicity of various concentrations (0.25%, 0.5%, 1%, 2.5%, 5%) of both solutions (BioAKT and BioAKT Endo) was assessed on L-929 mouse fibroblasts using the MTT assay. For the quantitative analysis of components, an infrared (I.R.) spectroscopy was performed. The minimum inhibitory and minimal bactericidal concentrations (M.I.C. and M.B.C., respectively) were ascertained on Enterococcus faecalis strain ATCC 4083. For biofilm susceptibility after treatment with the irrigating agent, a minimum biofilm eradication concentration (M.B.E.C.) and confocal laser scanning microscope (C.L.S.M.) assays were performed. Quantification of E. faecalis cell biomass and percentage of live and dead cells in the biomass was appraised. Normality of data was analyzed using the D’Agostino & Pearson’s test and the Shapiro–Wilk test. Statistical analysis was performed using one-way analysis of variance (ANOVA) and Tukey’s test. Both silver citrate solutions showed mouse fibroblasts viability >70% when diluted to 0.25% and 0.5%. Conversely, at higher concentrations, they were extremely cytotoxic. F.T.-IR spectroscopy measurements of both liquids showed the same spectra, indicating similar chemical characteristics. No substantial contrast in antimicrobial activity was observed among the two silver citrate solutions by using broth microdilution methods, biofilm susceptibility (MBEC-HTP device), and biomass screening using confocal laser scanning microscopy (C.L.S.M.) technique. Both solutions, used as root canal irrigants, exhibited significant antimicrobial activity and low cytocompatibility at dilutions greater than 0.5%

Modeling Forbidden Line Emission Profiles from Colliding Wind Binaries

This paper presents calculations for forbidden emission line profile shapes arising from colliding wind binaries. The main application is for systems involving a Wolf-Rayet (WR) star and an OB star companion. The WR wind is assumed to dominate the forbidden line emission. The colliding wind interaction is treated as an archimedean spiral with an inner boundary. Under the assumptions of the model, the major findings are as follows. (a) The redistribution of the WR wind as a result of the wind collision is not flux conservative but typically produces an excess of line emission; however, this excess is modest at around the 10% level. (b) Deviations from a flat-top profile shape for a spherical wind are greatest for viewing inclinations that are more nearly face-on to the orbital plane. At intermediate viewing inclinations, profiles display only mild deviations from a flat-top shape. (c) The profile shape can be used to constrain the colliding wind bow shock opening angle. (d) Structure in the line profile tends to be suppressed in binaries of shorter periods. (e) Obtaining data for multiple forbidden lines is important since different lines probe different characteristic radial scales. Our models are discussed in relation to ISO data for WR 147 and gamma Vel (WR11). The lines for WR 147 are probably not accurate enough to draw firm conclusions. For gamma Vel, individual line morphologies are broadly reproducible but not simultaneously so for the claimed wind and orbital parameters. Overall, the effort demonstrates how lines that are sensitive to the large-scale wind can help to deduce binary system properties and provide new tests of numerical simulations.Comment: to appear in MNRA

Wind clumping and the wind-wind collision zone in the Wolf-Rayet binary gamma Velorum

We present XMM-Newton observations of gamma^2 Velorum (WR 11, WC8+O7.5III, P = 78.53 d), a nearby Wolf-Ray binary system, at its X-ray high and low states. At high state, emission from a hot collisional plasma dominates from about 1 to 8 keV. At low state, photons between 1 and 4 keV are absorbed. The hot plasma is identified with the shock zone between the winds of the primary Wolf-Rayet star and the secondary O giant. The absorption at low state is interpreted as photoelectric absorption in the Wolf-Rayet wind. This absorption allows us to measure the absorbing column density and to derive a mass loss rate 8x10^{-6} M_sun/yr for the WC8 star. This mass loss rate, in conjunction with a previous Wolf-Rayet wind model, provides evidence for a clumped WR wind. A clumping factor of 16 is required. The X-ray spectra below 1 keV (12 Ang) show no absorption and are essentially similar in both states. There is a rather clear separation in that emission from a plasma hotter than 5 MK is heavily absorbed in low state while the cooler plasma is not. This cool plasma must come from a much more extended region than the hot material. The Neon abundance in the X-ray emitting material is 2.5 times the solar value. The unexpected detection of CV (25.3 Ang) and CVI (31.6 Ang) radiative recombination continua at both phases indicates the presence of a cool (~40,000 K) recombination region located far out in the binary system.Comment: 16 page