Hierarchical Intrafibrillarly Mineralized Collagen Membrane Promotes Guided Bone Regeneration and Regulates M2 Macrophage Polarization.

Mineralized collagen has been introduced as a promising barrier membrane material for guided bone regeneration (GBR) due to its biomimetic nanostructure. Immune interaction between materials and host significantly influences the outcome of GBR. However, current barrier membranes are insufficient for clinical application due to limited mechanical or osteoimmunomodulatory properties. In this study, we fabricated hierarchical intrafibrillarly mineralized collagen (HIMC) membrane, comparing with collagen (COL) and extrafibrillarly mineralized collagen (EMC) membranes, HIMC membrane exhibited preferable physicochemical properties by mimicking the nanostructure of natural bone. Bone marrow mesenchymal stem cells (BMSCs) seeded on HIMC membrane showed superior proliferation, adhesion, and osteogenic differentiation capacity. HIMC membrane induced CD206+Arg-1+ M2 macrophage polarization, which in turn promoted more BMSCs migration. In rat skull defects, HIMC membrane promoted the regeneration of new bone with more bone mass and more mature bone architecture. The expression levels of Runx2 and osterix and CD68 + CD206 + M2 macrophage polarization were significantly enhanced. HIMC membrane provides an appropriate osteoimmune microenvironment to promote GBR and represents a promising material for further clinical application.

[Experimental evaluation of pure traditional Chinese medical mouth rinse on skin and mucosa stimulation and bacteriostatic-bactericidal effect].

PURPOSE: To observe the stimulating effect of pure traditional Chinese medical mouth rinse (PTCMMR) on skin and mucosa and to evaluate the efficacy of PTCMMR on inhibiting and killing oral common bacteria. METHODS: PTCMMR and normal saline (NS) were separately dripped onto 14 five-month rabbits' left and right eyes for 7 days, and were smeared on the left and right side of buttocks, abdomens, back of 10 seven-month guinea pigs (after hair removal) once a day for comparison between the two sides. Five animals were sacrificed after 3 and 7 days of smearing to make pathological sections. Bacterium suspension with Staphylococcus aureus, Escherichia coli, Candida albicans, Pseudomonas aeruginosa and Streptococcus B were dropped to nutrient solution containing different concentrations of PTCMMR or compound Borax solution to observe the growth situation of bacteria. Inhibition zone diameters were measured after 18h of incubation within 37 degrees centigrade incubator. The data was statistically analyzed using SPSS 17.0 software package. RESULTS: There was no obvious change such as redness, dermatitis between rabbits' left eye conjunctiva and the control group. The bacteriostatic and bactericidal effect of anaerobe and aerobe with dropping of PTCMMR was stronger than that of control group. CONCLUSIONS: PTCMMR has no stimulation to skin and mucosa, while it has strong efficacy to inhibit and kill oral common bacteria.