Proteomic Changes during the Dermal Toxicity Induced by Nemopilema nomurai Jellyfish Venom in HaCaT Human Keratinocyte

Dual-crosslinked network of polyacrylamide-carboxymethylcellulose hydrogel promotes osteogenic differentiation in vitro

In our previous study, we successfully designed a dual-crosslinked network hydrogel by introducing the monomers acrylamide (AM), carboxymethylcellulose (CMC), zeolitic imidazolate framework-8 (ZIF-8), and alendronate (Aln). With the simultaneous presentation of physical and chemical crosslinks, the fabricated hydrogel with 10 % concentration of Aln@ZIF-8 (PAM-CMC-10%Aln@ZIF-8) exhibited excellent mechanical characteristics, high Aln loading efficiency (63.83 %), and a slow release period (6 d). These results demonstrate that PAM-CMC-10%Aln@ZIF-8 is a potential carrier for delaying Aln. In this study, we mainly focused on the biocompatibility and osteogenic ability of PAM-CMC-10%Aln@ZIF-8 in vitro, which is a continuation of our previous work. First, this study investigated the biocompatibility of dual-crosslinked hydrogels using calcein-AM/Propidium Iodide and cell counting kit-8. The morphology of rat bone mesenchymal stem cells was assessed using FITC-phalloidin/DAPI and vinculin immunostaining. Finally, osteogenic induction ability in vitro was assessed via alkaline phosphatase expression and alizarin red S staining, which was also confirmed using real-time PCR at the gene level and immunofluorescence at the protein level. The results indicated that the introduction of Aln enabled a dual-crosslinked hydrogel with superior biocompatibility and outstanding osteogenic differentiation ability in vitro, providing a solid foundation for subsequent animal experiments in vivo.

The osteogenic effects of porous Tantalum and Titanium alloy scaffolds with different unit cell structure

Porous scaffolds have long been regarded as optimal substitute for bone tissue repairing. In order to explore the influence of unit cell structure and inherent material characteristics on the porous scaffolds in terms of mechanical and biological performance, selective laser melting (SLM) technology was used to fabricate porous tantalum (Ta) and titanium alloy (Ti6Al4V) with diamond (Di) or rhombic dodecahedron (Do) unit cell structure. The mechanical strength of all the porous scaffolds could match that of trabecular bone, while the biological performance of each scaffold was diverse from each other. Moreover, the ILK/ERK1/2/Runx2 signaling pathway had been verified to be involved in the osteogenic differentiation of rat bone mesenchymal stem cells (rBMSCs) cultured on those porous scaffolds. Unit cell structure and material characteristics of the porous Ta and Ti6Al4V scaffolds can synergistically modulate this axis and further impact on the osteogenic effects. Our results hence illustrate that porous Ta scaffold with diamond unit cell structure possesses excellent osteogenic effects and moderate mechanical strength and porous Ti6Al4V scaffold with rhombic dodecahedron unit cell structure has the highest mechanical strength and moderate osteogenic effects. Both porous Ta and Ti6Al4V can be applied in different settings requiring either better biological performance or higher mechanical demand.