Preparation of CaMgAl-calcined layered double hydroxides and application on the removal of phosphates.

A calcined CaMgAl-layered double hydroxide nanocomposite, CaMgAl-LDH (CCMA-0.83-600), was prepared by introducing Mg on the basis of CaAl-LDHs for the removal of phosphate from wastewater. The structure of the as-synthesized CCMA-0.83-600 was confirmed by XRD and SEM analyses. Parameters affecting the adsorption process of phosphate adsorbed by CCMA-0.83-600 were thoroughly explored, such as initial pH, adsorbent dosage and co-existing anions. The adsorption kinetic study suggested that the adsorption process accorded with the pseudo-second-order kinetic model and the adsorption rate was controlled by both the liquid film diffusion and intra-particle diffusion. The adsorption isotherm study indicated the adsorption process followed by the Langmuir isotherm model. Thermodynamic analysis suggested that the adsorption of phosphate was spontaneous and exothermic. The obtained results indicated that CCMA-0.83-600 is a suitable candidate for the removal of phosphate from wastewater.

Caries outcome following an intensive fluoride varnish treatment regimen for children at high risk for early childhood caries.

PURPOSE: To evaluate the caries relapse rate for a cohort of 2- to 4-year-old children at high risk of early childhood caries when treated with an intensive fluoride varnish (FV) regimen. METHODS: Eighty paediatric patients were recruited. Forty of these patients were high risk and received the FV treatment (three applications within 2 weeks and additional applications at 1 and 3 months) during 2009-2010. Mutans streptococci (MS) levels in the saliva were evaluated during the treatment period. A comparative group of 40 children, selected from an electronic record search at the New York University College of Dentistry to be of similar age, gender, and ethnicity, but not at elevated risk for ECC, received the standard of care (semi-annual FV treatment). Detailed caries examination and treatment records were obtained for all patients from 2009 to 2014. RESULTS: A significant reduction (P < 0.001) in MS levels was observed in the intensive FV treatment group at the 3-month visit compared with baseline. There was no effect of the intensive FV treatment on caries outcome in the anterior teeth, and the overall caries scores were significantly increased on the posterior teeth. CONCLUSION: The intensive FV regimen appears insufficient to prevent caries relapse in children at high risk for caries.

Transglutaminase-mediated oligomerization promotes osteoblast adhesive properties of osteopontin and bone sialoprotein.

Tissue transglutaminase (TG2) is a widely distributed, protein-crosslinking enzyme having a prominent role in cell adhesion as a ß1 integrin co-receptor for fibronectin. In bone and teeth, its substrates include the matricellular proteins osteopontin (OPN) and bone sialoprotein (BSP). The aim of this study was to examine effects of TG2-mediated crosslinking and oligomerization of OPN and BSP on osteoblast cell adhesion. We show that surfaces coated with oligomerized OPN and BSP promote MC3T3-E1/C4 osteoblastic cell adhesion significantly better than surfaces coated with the monomeric form of the proteins. Both OPN and BSP oligomer-adherent cells showed more cytoplasmic extensions than those cells grown on the monomer-coated surfaces indicative of increased cell connectivity. Our study suggests a role for TG2 in promoting the cell adhesion function of two matricellular substrate proteins prominent in bone, tooth cementum and certain tumors.