Zobrazení zdroje stránky Henrybenton2700

Metallic implant biomaterials predominate in orthopaedic surgery. Compared to titanium-based permanent implants, magnesium-based ones offer new possibilities as they possess mechanical properties closer to the ones of bones and they are biodegradable. Furthermore, magnesium is more and more considered to be "bioactive" i.e., able to elicit a specific tissue response or to strengthen the intimate contact between the implant and the osseous tissue. Indeed, several studies demonstrated the overall beneficial effect of magnesium-based materials on bone tissue (in vivo and in vitro). Here, the direct effects of titanium and magnesium on osteoblasts were measured on proteomes levels in order to highlight metal-specific and relevant proteins. Out of 2100 identified proteins, only 10 and 81 differentially regulated proteins, compare to the control, were isolated for titanium and magnesium samples, respectively. Selected ones according to their relationship to bone tissue were further discussed. Most of them were involved in extracellular matrix maturation and remodelling (two having a negative effect on mineralisation). A fine-tuned balanced between osteoblast maturation, differentiation and viability was observed.The synergistic combination of gene therapy and photothermal therapy (PTT) has been widely investigated as a promising strategy for cancer treatment. To deliver genes and photothermal agents simultaneously and accurately to a tumor site, a microneedle (MN) patch co-loaded with p53 DNA and IR820 was fabricated by a two-step casting method. Hyaluronic acid was chosen as a matrix and p53 DNA and IR820 were mainly loaded into the tips to enhance utilization and reduce waste. The MN patch could efficiently penetrate the stratum corneum, and dissolve rapidly to release p53 DNA and IR820 in the subcutaneous tumor site. Due to the efficient photothermal efficacy of IR820, the temperature of the tumor site where the MN patch was applied increased by 14.7 °C under near-infrared light irradiation. The MN patch showed excellent antitumor effects in vivo owing to the synergistic effect of gene therapy and PTT. Consequently, the p53 DNA/IR820 MN patch may be a promising synergistic strategy for subcutaneous tumor treatments.We demonstrate that the conductance switching of benzo-bis(imidazole) molecules upon protonation depends on the lateral functional groups. The protonated H-substituted molecule shows a higher conductance than the neutral one (Gpro &gt; Gneu), while the opposite (Gneu &gt; Gpro) is observed for a molecule laterally functionalized by amino-phenyl groups. These results are demonstrated at various scale lengths self-assembled monolayers, tiny nanodot-molecule junctions and single molecules. From ab initio theoretical calculations, we conclude that for the H-substituted molecule, the result Gpro &gt; Gneu is correctly explained by a reduction of the LUMO-HOMO gap, while for the amino-phenyl functionnalized molecule, the result Gneu &gt; Gpro is consistent with a shift of the HOMO, which reduces the density of states at the Fermi energy.Peptide backbone amide substitution can dramatically alter the conformational and physiochemical properties of native sequences. Although uncommon relative to N-alkyl substituents, peptides harboring main-chain N-hydroxy groups exhibit unique conformational preferences and biological activities. Here, we describe a versatile method to prepare N-hydroxy peptide on solid support and evaluate the impact of backbone N-hydroxylation on secondary structure stability. Based on previous work demonstrating the β-sheet-stabilizing effect of α-hydrazino acids, we carried out an analogous study with N-hydroxy-α-amino acids using a model β-hairpin fold. In contrast to N-methyl substituents, backbone N-hydroxy groups are accommodated in the β-strand region of the hairpin without energetic penalty. An enhancement in β-hairpin stability was observed for a di-N-hydroxylated variant. Our results facilitate access to this class of peptide derivatives and inform the use of backbone N-hydroxylation as a tool in the design of constrained peptidomimetics.tert-Butyl-p-benzoquinone (TBBQ), a metabolite of tert-butylhydroquinone from food, has cytotoxicity, the underlying mechanism of which is not clear. In this study, the viability of RAW 264.7 cells exposed to TBBQ at concentrations of 0.5-10 μg mL-1 was assayed by MTT. Results suggest that TBBQ decreased the viability in a dose-dependent manner. [https://www.selleckchem.com/products/arv471.html ARV471 order] Monodansylcadaverine (MDC) staining results indicate the occurrence of autophagy induced by TBBQ, which was manifested by activation of LC3-II concurrent with the increased levels of Beclin1 and reduced levels of p62. Elevated lipid peroxide and decreased SOD activity by TBBQ exposure suggest the overproduction of ROS, which may account for the increase in the genotoxic stress protein p53. Both upregulation of p53 and reduction of Akt levels inhibited mTOR, which activated autophagy. Addition of 3-MA counteracted the impact of TBBQ on ATG proteins and cell viability. All of these results suggest that TBBQ induces autophagy of RAW 264.7 cells principally by inhibition of the Akt/mTOR signaling pathway, and they implicate ROS in this regulation.Supramolecular self-assembly allows components to organize themselves into regular patterns by using non-covalent interactions to find the lowest-energy configuration. However, self-assembling organic and inorganic building blocks together into an ordered framework remains a challenge due to the difficulties in rationally interfacing two dissimilar materials. Herein, we report on the host-guest ensemble of polyoxometalates (POMs) using cyclodextrins (CDs) as the trapping agent to form POM@γ-CD entities. Two unprecedented super cubic isostructures, Co/Cu-PW12O40-γ-CD, were obtained. The self-assembly has been observed both in solution (MS, 1D NMR and 2D DOSY) and in the solid state. Single-crystal X-ray diffraction reveals that in a unit cell, the inner (POM@γ-CD)12 cube is encapsulated by the outer (POM@γ-CD)24 cube. Besides, due to the rather large spherical voids, two (POM@γ-CD)24 cubes are interspersed together. Preliminary investigations of the redox properties of the [PW12O40]3- encapsulated in the γ-cyclodextrins indicate that the redox properties of the trianion are largely retained, yet an additional electrochemical stabilization is observed.