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Argpyrimidine (APMD), a methylglyoxal-arginine-derived product, is one of the main products of diabetes mellitus. We aimed to systematically investigate the role of APMD in regulating autophagy activity, with a specific focus on the finding of APDM binding molecule, matching amino acid residues, autophagy flux and proteins, cell cycle arrest, cell skeleton and migration, PI3K/AKT/mTOR pathways, inflammatory signals, alveolar bone destruction, and inhibition verification. In this study, binding to 59/94/121 amino acid residues of advanced glycosylation end product receptor (RAGE), APMD suppressed PI3K/AKT/mTOR pathway to attenuate cell survival of periodontal ligament cells (PDLCs). Simultaneously, autophagy proteins ATG5, Beclin1, and LC3-II/I expression ratio were upregulated while P62/SQSTM was downregulated. Cell cycle arrested at G0/G1 with enhancing Cyclin D1/CDK4 and decreasing Cyclin A/CDK2 expression. Inhibition of autophagy abrogated APMD-induced cell cycle arrest. Furthermore, the inflammation regulation network of matrix metalloproteinase (MMP)-2, MMP-9, MAPKs and NF-κB pathways were activated by APMD. Rat periodontal models confirmed that APMD induced alveolar bone resorption, increased inflammatory infiltrates, and degraded collagen fibers through RAGE and PI3K. APMD-induced autophagy, G0/G1 arrest, pro-inflammatory signals activating and periodontal destruction were reversed by RAGE knockdown while aggravated by PI3K inhibitor. This study provides the first evidence that APMD bind to RAGE to regulate autophagy and cell cycle of PDLCs through the PI3K/AKT/mTOR pathway, thereby promoting periodontal destruction.

The design of pore structure is the key factor for the performance of porous carbon spheres. In this work, novel micron-sized colloidal crystal microspheres consisting of fibrous silica (F-SiO2) nanoparticles are firstly prepared by water-evaporation-induced self-assembly of F-SiO2 nanoparticles in the droplets of an inverse emulsion system to be used as sacrificial templates. Acrylonitrile (AN) was infiltrated in the voids of the F-SiO2 colloidal crystal microspheres, and in-situ induced by 60Co γ-ray to polymerize into polyacrylonitrile (PAN). After the PAN-infiltrated F-SiO2 colloidal crystal microspheres were carbonized and etched with HF solution, novel micron-sized inverse-opal N-doped carbon (IO-NC) microspheres consisting of hollow carbon nanoparticles with a hierarchical macro/meso-porous inner surface were obtained. The IO-NC microspheres have a specific surface area as high as 266.4 m2/g and a molar ratio of C/N of 5. They have a good dispersibility in water, and show a high adsorption capacity towards rhodamine B (RhB) up to 137.28 mg/(g microsphere). This work offers a way to obtain novel micron-sized hierarchical macro/meso-porous N-doped carbon microspheres, which opens a new idea to prepare high-performance hierarchical porous carbon materials.

In view of the biological significance and micro-heterogeneity of protein glycosylation for human health, specific enrichment of N-glycosylated proteins/peptides from complex biological samples is a prerequisite for the discovery of disease biomarkers and clinical diagnosis. In this work, we propose a "grafting-from" N-glycoprotein enriching method based on the in-situ growth of thermoresponsive polymer brushes from the N-glycosylated site of proteins. The initiator was first attached to the pre-oxidized glycan moieties by hydrazide chemistry, from which the thermoresponsive polymers can be grown to form giant protein-polymer conjugates (PPC). The thermosensitive PPC can be precipitated and separated by raising the temperature to above its lower critical solubility temperature (LCST). Mass spectrometry verified 210 N-glycopeptides corresponding to 136 N-glycoproteins in the rabbit serum. These results demonstrate the capability of the tandem thermoprecipitation strategy to enrich and separate N-glycoprotein/glycopeptide. Due to its simplicity and efficiency specifically, this method holds the potential for identifying biomarkers from biological samples in N-glycoproteome analysis.

This study aimed to design a modified subgingival sling suture for periodontally accelerated osteogenic orthodontics (PAOO) as well as evaluate postoperative effects including gingival recession (GR), alveolar bone crest resorption, dental plague accumulation on sutures and alveolar bone augmentation. Twelve patients with bone defects in the anterior alveolar region of the mandible were included in this study. Subgingival sling suture, developed from traditional sling suture, was applied in modified PAOO operation. Probing depth, bleeding index, and GR were assessed, and cone-beam computerized tomography and laser microscope for thread surface were evaluated at baseline, postoperative 1 and 3 months to analyze the effects. Alveolar bone thickness on the labial side at the midpoint of the middle third of the root increased from 0.96 ± 0.28 mm to 3.38 ± 0.61 mm (P .01), and that of the apical third advanced from 1.26 ± 0.33 mm to 3.61 ± 1.02 mm (P .01), both exhibiting significant increase. No significant alveolar bone crest loss, probing depth increase, GR, and attachment loss was observed. This modified PAOO operation, associated with novel subgingival sling suture, productively augments alveolar bone volume and addresses problems in terms of GR and vertical loss of alveolar bone.