Objective: To investigate the effect of silane contents on their chemical interaction with 10-methacryloyloxydecyl-dihydrogen phosphate (MDP), and affecting the bonding of MDP to zirconia by time-of-flight secondary ion mass spectrometry (TOF-SIMS) and solid-state nuclear magnetic resonance (SSNMR) spectroscopy.
Methods: Zirconia (Cercon ht, Dentsply) slabs were prepared and fully sintered. Experimental primers SE-5 and SE-10 were formulated by adding 5 wt% and 10 wt% γ-methacryloxypropyltrimethoxysilane to an MDP-based primer SE BOND (SE), respectively. SE, SE-5, and SE-10 were applied on the assigned zirconia slabs. The chemical compositions on the surface and adhesive interfaces were examined by TOF-SIMS in a depth-profiling mode. Hydrophilicity and resin affinity of treated zirconia were analyzed. The bond strengths to resin cylinder were examined either after 24-h storage or thermocycles. In addition, zirconia powders treated with three primers were assessed by SSNMR spectrometry for the adsorption of MDP.
Results: TOF-SIMS analysis showed that SE treatment generated the greatest amount of P-O-Zr related ions, which reduced in SE-5 and SE-10 groups. The 3D ion-images illustrated the generation of ZrO(OH) ions with silane contents. The SSNMR analysis revealed that the chemical bonding was mainly P-O-Zr ionic bonds in SE but shifted to P-OH-Zr hydrogen bonds in SE-5 and SE-10. SE-5 and SE-10 treated zirconia presented higher hydrophilicity and affinity to resin compared to Zr did. SE showed the highest initial bond strength which significantly decreased after thermocycling.
Significance: MDP adsorption onto zirconia via P-O-Zr ionic bond promotes bonding with resin. The silane enhances the hydroxylation of zirconia and impairs the adsorption of MDP, but does not adversely affect the bond durability.
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http://dx.doi.org/10.1016/j.dental.2022.02.014 | DOI Listing |
Appl Physiol Nutr Metab
August 2024
Department of Nutritional Sciences, University of Toronto, Toronto, ON, Canada.
Household food insecurity is generally associated with poorer quality diets in Canada, but whether household food insecurity heightens the probability of inadequate micronutrient intakes is unknown. The objective of this research was to investigate how prevalence of micronutrient inadequacy differed by severity of household food insecurity among adults in Canada. Using the 2015 Canadian Community Health Survey Nutrition, this study included participants aged 19-64 years who completed up to two 24 h dietary recalls and provided details about household food insecurity ( = 9486).
View Article and Find Full Text PDFJAMA Oncol
March 2024
Department of Population Health Sciences, Duke University School of Medicine, Durham, North Carolina.
Importance: Some individuals are predisposed to cancer based on their substance use history, and others may use substances to manage cancer-related symptoms. Yet the intersection of substance use disorder (SUD) and cancer is understudied. Because SUD may affect and be affected by cancer care, it is important to identify cancer populations with a high prevalence of SUD, with the goal of guiding attention and resources toward groups and settings where interventions may be needed.
View Article and Find Full Text PDFJ Dent (Shiraz)
June 2023
Dept. of Traditional Medicine, School of Persian medicine, Tehran University of Medical Sciences, Tehran, Iran.
Statement Of The Problem: Although sumac extract (SE) is reported as a collagen cross linker, the available data regarding its effect on the dentine micro-hardness is quite sparse.
Purpose: Therefore, the aim of this study includes evaluating the effect of different concentrations of SE on dentine micro-hardness comparing to grape seed extract (GSE).
Materials And Method: In this experimental study, the GSE was purchased from available market and convert to 5% solution.
Neurology
July 2023
From the Division of Public Health Sciences (J.L.), Department of Surgery, Siteman Cancer Center Biostatistics Core (J.L.), Division of Biostatistics (J.L., Y.M., F.J.A., E.G., C.X.), Knight Alzheimer Disease Research Center (Y.M., F.J.A., E.G., J.C.M., A.M.F., T.L.S.B., J.H., R.J.B., R.J.P., B.A.G., C.X.), Department of Neurology (J.C.M., E.M., A.M.F., J.H., R.J.B., R.J.P., M.G., J.F.S.), Department of Pathology and Immunology (J.C.M., R.J.P.), and Department of Radiology (T.L.S.B., B.A.G., M.G.), Washington University School of Medicine, St. Louis, MO; Department of Nuclear Medicine (I.Y.), and Klinikum rechts der Isar (I.Y.), School of Medicine, Neuroimaging Center (TUM-NIC), Technical University of Munich, Germany; and Department of Neurology (G.S.D.), Mayo Clinic, Jacksonville, FL.
Background And Objectives: White matter hyperintensities (WMH) correlate with Alzheimer disease (AD) biomarkers cross-sectionally and modulate AD pathogenesis. Longitudinal changes have been reported for AD biomarkers, including concentrations of CSF β-amyloid (Aβ) 42, Aβ40, total tau and phosphorylated tau181, standardized uptake value ratio from the molecular imaging of cerebral fibrillar Aβ with PET using [C] Pittsburgh Compound-B, MRI-based hippocampal volume, and cortical thickness. Correlations between established AD biomarkers and the longitudinal change for WMH have not been fully evaluated, especially among cognitively normal individuals across the adult life span.
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