A specific population of adipose-derived stem cells (ASCs) is expected to be an alternate source of bone marrow-derived mesenchymal stem cells (BMSCs). To accelerate their osteogenic differentiation, we overexpressed the osteogenic transcription factor Cbfa1 (Core binding factor alpha-1, Til-1) gene using an adenovirus vector in rat ASCs. The results revealed that the osteoblastic markers, such as ALP activity, the osteocalcin expression, and calcium content, in Cbfa1-overexpressing ASCs were markedly greater than those of control ASCs. Moreover, we transplanted Cbfa1-overexpressing ASCs/porous materials into subcutaneous sites in Fisher rats. The bone formation was markedly increased by the overexpression, compared to the control which partially dedifferentiated into adipocytes by 8 weeks after implantation. These findings suggested that overexpression of the Cbfa1 gene induced a remarkable and rapid differentiation of ASCs into osteogenic cells. In vitro and in vivo results implied that Cbfa1-overexpressing ASCs may be an alternative cell source for BMSCs for bone tissue engineering.
The conformations of stable calcium (Ca) ion complexes of three vinylbenzoic acid isomers (i.e., p-VBA, m-VBA, and o-VBA) and their reactivity toward Ca ion were investigated by computational approaches to investigate the remineralization potential of VBAs. The quantum chemistry CAChe software package was used for benchtop molecular design. Molecular mechanics (MM) calculations were used to determine the lowest steric energy structures of the VBAs and the VBA-Ca ion complexes. The steric energy of the m-VBA-Ca ion complex is larger than those obtained for complexes with p-VBA and o-VBA. The steric energy difference between the VBA-Ca ion complexes and the corresponding VBA (ΔE*) was obtained. The ΔE* of m-VBA was approximately 3–5 times higher than those of p-VBA and o-VBA. The energies of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of each VBA was obtained by molecular orbital (MO) calculations. p-VBA showed the lowest LUMO and HOMO energy levels, and their energy difference was very small compared with m-VBA and o-VBA. Comparing the energy differences between the LUMO of the Ca ion and the HOMO of the VBAs (ΔE**), p-VBA showed a slightly larger ΔE** than both m-VBA and o-VBA. Although no correlation was found between the ΔE* and ΔE**, it is suggested that o-VBA has a higher reactivity toward Ca ion due to its smaller ΔE* and ΔE**. Overall, it is suggested that the reactivity of VBAs toward Ca ion and their remineralization potential are influenced by the specific isomer of VBAs.
Periodontitis is common in adults and cardiovascular diseases are the most common cause of adult death in the world. However opening of the infarct-related coronary artery is a valued therapeutic goal in acute myocardial infarction, cardiomyocytes continue to die during reperfusion. Acute oxidative stress induced by ischemia –reperfusion causes serious damage to tissue. The purpose of our study was to investigate that hydrogen (H2) gas has potential as an antioxidant in preventive and therapeutic applications. We first determined the dose at which cytotoxicity develops in a period of 1 h upon antimycin A (AA) exposure in H9c2 cells. AA (0-500 μM) exhibited cytotoxicity in a concentration-dependent manner. A maximum reduction was 76.5 ± 4 of the control group (at 500 μM of AA). AA-induced cytotoxicity in H9c2 cells were improved by H2 gas. These results suggested the protective effects H2 gas against AA- induced injury in H9c2 cells.
A titanium (Ti) mesh using the Selective Laser Melting (SLM) technique was subjected to surface modification by mixed acid heating, and it was applied to a rat calvarial bone defect model. Safety of the mixed acid heat treatment on the surface was evaluated by investigating the inflammatory response based on macroscopic and microscopic findings. Worsening of inflammatory reactions was not observed in the SLM Ti mesh-embedded group at 2, 4 or 7 weeks. These results suggest that mixed acid and heat treatment surface modification Ti mesh is safe.
Oral implants have an ideal structure of a device capable of releasing a very small amount of various drugs from the fixture because it is placed in hard and soft tissues with abundant capillary blood vessels. Many elderly patients receive oral implant treatment and many of them also have complications, for whom the usefulness of commercializing an oral implant with drug release function is significant. I have proposed intraoral prostheses, such as a crown, bridge, and denture, and oral implants capable of releasing a very small amount of drugs. In this study, it was further advanced, and utilization of the oral implant as a micro organ to treat endocrine disease as medical-dental collaboration was proposed.