Correlations among core species corresponding to the clinical staging of periodontitis

The correlation between microbiota plays a vital role in the progression of periodontal disease.This study investigated the in situ interaction networks between periodontal pathogens in periodontal and peri-implant disease.We used quantitative real-time polymerase chain reaction and Pearson’s correlation coefficients to quantify the copy numbers and correlations of four oral core species—Fusobacterium nucleatum,Porphyromonas gingivalis,Prevotella intermedia,and Streptococcus gordonii—from 80 subgingival sites(healthy and with periodontitis or gingivitis)in patients with periodontitis,and 68 subgingival sites(healthy and with periodontitis,gingivitis,peri-implantitis,or peri-implant mucositis)in patients with implants.The highest bacterial counts were observed for Porphyromonas gingivalis and Prevotella intermedia at all the sites.Within the same cohorts,the bacterial loads were greater at diseased sites than at healthy sites.Bacterial counts did not differ among clinical sites in the same group(P>0.05)but differed between periodontitis and peri-implant mucositis sites in the two groups.Porphyromonas gingivalis,F.nucleatum,and Prevotella intermedia had strong correlations at gingivitis and healthy sites and moderate correlations at periodontitis sites in patients with periodontitis.In patients with implants,Prevotella intermedia,F.nucleatum,and S.gordonii had strong correlations only at peri-implantitis sites.Also,based on metagenomic analysis,F.nucleatum and Prevotella intermedia were significantly correlated at the subgingival plaque in peri-implantitis and periodontitis samples.Our results suggest that variations in microbe-microbe interactions in subgingival plaque reflect changes in the progression of periodontal disease,providing a new perspective for understanding the mechanisms of periodontitis and peri-implantitis.

Microstructure, mechanical, and corrosion properties of extruded low-alloyed Mg–xZn–0.2Ca alloys

The microstructure, mechanical, and corrosion properties of extruded low-alloyed Mg xZn 0.2Ca (x=0, 1.0, 2.0, 3.0) alloys were investigated in this study. Findings from scanning electron microscope, X-ray diffraction and transmission electron microscopy results indicate that the amount of ternary Ca2Mg6Zn3 phase, as the only secondary phase in 1.0Zn, 2.0Zn, and 3.0Zn alloys, gradually increases with the addition of Zn, while the Mg2Ca phase was observed in the Mg 0.2Ca alloy only. Zn has a strong effect on the orientation and intensity of textures, which also influence mechanical behaviors, as revealed by electron back-scatter diffraction. Among all the alloys, the Mg 2.0Zn 0.2Ca alloy obtains the maximum tensile strength (278 MPa) and yield strength (230 MPa). Moreover, Zn addition has an evident influence on the corrosion properties of Mg xZn 0.2Ca alloy, and Mg 1.0Zn 0.2Ca alloy exhibits the minimum corrosion rate. This paper provides a novel low-alloyed magnesium alloy as a potential biodegradable material.

Long non-coding RNAMIR22HG inhibits the adipogenesis of human bone marrow mesenchymal stem cells with the involvement of Wnt/β-catenin pathway

Osteoporosis is a frequently occurring bone remodeling disorder worldwide with one characteristic being decreasing bone mineral density and a predisposition to bone fracture,which diminishes patients’quality of life.Several studies showed that imbalance between the osteogenesis and adipogenesis of bone marrow mesenchymal stem cells(BMSCs)took part in the development of osteoporosis.In previous study,we found MIR22HG regulated the osteogenesis of human BMSCs positively.In this study,we found that MIR22HG was decreased during the adipogenesis of human BMSCs and exerted negative effects on adipogenesis with the involvement of Wnt/β-catenin signaling pathway both in vitro and in vivo.Nitazoxanide could inhibit Wnt signaling and relieve MIR22HG’s suppression on adipogenesis.These findings indicated that MIR22HG had great potential in clinical application for osteoporosis treatment and prevention.

Ultraclean transfer of graphene by mechanically exfoliating polymer with modified crosslink density

The transfer of graphene from metallic substrates onto application-specific substrates is usually inevitable for the applications of high-quality graphene films derived from chemical vapour deposition(CVD)approaches.Commonly used to support the graphene films during the transfer,the coating of the polymer would produce the surface contaminations and hinder the industrially compatible transfer.In this work,through the thermal imidization of polyamide acid(PAA)to polyimide(PI)and tuning of the concentration of dangling chains,we achieved the ultraclean and crack-free transfer of graphene wafers with high electronic quality.The resulting contamination-free and hydrophilic surface also enabled the observed improved cell viability in a biomedical applications.By avoiding aqueous etching or the usage of strong bases,our proposed transfer method is industrially compatible for batch transfer of graphene films towards the real applications.

Utilizing 3D bioprinted platelet-rich fibrin-based materials to promote the regeneration of oral soft tissue

Oral soft tissue defects remain difficult to treat owing to the limited efficacy of available treatment materials.Although the injectable platelet-rich fibrin(i-PRF)is a safe,autologous source of high levels of growth factors that is often employed to promote the regeneration of oral soft tissue,its effectiveness is restrained by difficulties in intraoperative shaping together with the burst-like release of growth factors.We herein sought to develop a bioactive bioink composed of i-PRF,alginate and gelatin capable of promoting the regeneration of the oral soft tissue.This bioink was successfully applied in 3D bioprinting and exhibited its ability to be shaped to individual patient needs.Importantly,we were also able to significantly prolong the duration of multiple growth factors release as compared to that observed for i-PRF.The growth factor bioavailability was further confirmed by the enhanced proliferation and viability of printed gingival fibroblasts.When deployed in vivo in nude mice,this bioink was further confirmed to be biocompatible and to drive enhanced angiogenic activity.Together,these data thus confirmthe successful production of an i-PRF-containing bioink,which is suitable for the individualized promotion of the regeneration of oral soft tissue.