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Hollingsworth J.V.,Louisiana State University | Hollingsworth J.V.,University of St. Thomas, Texas | Bhupathiraju N.V.S.D.K.,Louisiana State University | Sun J.,Dr Anthony Volpe Research Center | And 4 more authors.
ACS Applied Materials and Interfaces | Year: 2016

A facile approach using click chemistry is demonstrated for immobilization of metalloporphyrins onto the surface of silica-coated iron oxide particles. Oleic-acid stabilized iron oxide nanocrystals were prepared by thermal decomposition of iron(III) acetylacetonate. Their crystallinity, morphology, and superparamagnetism were determined using X-ray diffraction, transmission electron microscopy, and a superconducting quantum interference device. Monodisperse core-shell particles were produced in the silica-coating of iron oxide via microemulsion synthesis. Surface modification of these particles was performed in two steps, which included the reaction of silica-coated iron oxide particles with 3-bromopropyltrichlorosilane, followed by azido-functionalization with sodium azide. Monoalkylated porphyrins were prepared using the Williamson ether synthesis of commercially available tetra(4-hydroxyphenyl) porphyrin with propargyl bromide in the presence of a base. 1H NMR and matrix-assisted laser desorption ionization confirmed the identity of the compounds. The prepared monoalkyne porphyrins were zinc-metalated prior to their introduction to azide-functionalized, silica-coated iron oxide particles in the click reaction. X-ray photoelectron spectroscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy were used to characterize the surface chemistry after each step in the reaction. In addition, particle size was determined using dynamic light scattering and microscopy. The presented methodology is versatile and can be extended to other photoreactive systems, such as phthalocyanines and boron-dipyrromethane, which may lead to new materials for optical, photonic, and biological applications. © 2015 American Chemical Society. Source


Kim J.J.,University of California at Los Angeles | Kim J.J.,Dr Anthony Volpe Research Center | Khalid O.,University of California at Los Angeles | Khalid O.,The Childrens Hospital of Orange County Research Institute | And 5 more authors.
Genomics Data | Year: 2014

It has been reported that nicotine/alcohol alters epigenetic control and leads to abrogated DNA methylation and histone modifications, which could subsequently perturb transcriptional regulation critically important in cellular transformation. The aim of this study is to determine the molecular mechanisms of nicotine/alcohol-induced epigenetic alterations and their mechanistic roles in transcriptional regulation in human adult stem cells. We hypothesized that nicotine/alcohol induces deregulation of epigenetic machinery and leads to epigenetic alterations, which subsequently affect transcriptional regulation in oral epithelial stem cells. As an initiating step we have profiled transcriptomic alterations induced by the combinatory administration of EtOH and nicotine in primary normal human oral keratinocytes. Here we provide detailed experimental methods, analysis and information associated with our data deposited into Gene Expression Omnibus (GEO) under GSE57634. Our data provide comprehensive transcriptomic map describing molecular changes induced by EtOH and nicotine on normal human oral keratinocytes. © 2014 The Authors. Source


Khalid O.,University of California at Los Angeles | Khalid O.,The Childrens Hospital of Orange County Research Institute | Kim J.J.,University of California at Los Angeles | Kim J.J.,Dr Anthony Volpe Research Center | And 5 more authors.
Genomics Data | Year: 2014

Human dental pulp stem cells (DPSCs) isolated from adult dental pulp are multipotent mesenchymal stem cells that can be directed to differentiate into osteogenic/odontogenic cells and also trans-differentiate into neuronal cells. The utility of DPSC has been explored in odontogenic differentiation for tooth regeneration. Alcohol abuse appears to lead to periodontal disease, tooth decay and mouth sores that are potentially precancerous. Persons who abuse alcohol are at high risk of having seriously deteriorated teeth, gums and compromised oral health in general. It is currently unknown if alcohol exposure has any impact on adult stem cell maintenance, stem cell fate determination and plasticity, and stem cell niche environment. Here we provide detailed experimental methods, analysis and information associated with our data deposited into Gene Expression Omnibus (GEO) under GSE57255. Our data provide transcriptomic changes that are occurring by EtOH treatment of DPSCs at 24-hour and 48-hour time point. © 2014 The Authors. Source


Kim J.J.,University of California at Los Angeles | Kim J.J.,Dr Anthony Volpe Research Center | Duan L.,University of California at Los Angeles | Tu T.G.,University of California at Los Angeles | And 5 more authors.
Genomics Data | Year: 2014

Potential teratogenic effects of alcohol on fetal development have been documented. Especially studies have demonstrated deleterious effect of ethanol exposure on neuronal development in animal models and on the maintenance and differentiation of neuronal precursor cells derived from stem cells. To better understand the molecular effect of alcohol on the process of neural differentiation, we have performed gene expression microarray analysis on human embryonic stem cells being directed to neural rosettes and neural precursor cells in the presence of ethanol treatment. Here we provide detailed experimental methods, analysis and information associated with our data deposited into Gene Expression Omnibus (GEO) under GSE56906. Our data provide scientific insight on potential molecular effects of fetal alcohol exposure on neural differentiation of early embryo development. © 2014 The Authors. Source


Marovic D.,University of Zagreb | Tarle Z.,University of Zagreb | Hiller K.-A.,University of Regensburg | Muller R.,University of Regensburg | And 3 more authors.
Dental Materials | Year: 2014

Objectives The aim of this study was to examine the influence of the addition of glass fillers with different sizes and degrees of silanization percentages to remineralizing composite materials based on amorphous calcium phosphate (ACP). Methods Four different materials were tested in this study. Three ACP based materials: 0-ACP (40 wt% ACP, 60 wt% resin), Ba-ACP (40 wt% ACP, 50 wt% resin, 10 wt% barium-glass) and Sr-ACP (40 wt% ACP, 50 wt% resin, 10 wt% strontium-glass) were compared to the control material, resin modified glass ionomer (Fuji II LC capsule, GC, Japan). The fillers and composites were characterized using scanning electron microscopy. Flexural strength and modulus were determined using a three-point bending test. Calcium and phosphate ion release from ACP based composites was measured using inductively coupled plasma atomic emission spectroscopy. Results The addition of barium-glass fillers (35.4 (29.1-42.1) MPa) (median (25-75%)) had improved the flexural strength in comparison to the 0-ACP (24.8 (20.8-36.9) MPa) and glass ionomer control (33.1 (29.7-36.2) MPa). The admixture of strontium-glass (20.3 (19.5-22.2) MPa) did not have any effect on flexural strength, but significantly improved its flexural modulus (6.4 (4.8-6.9) GPa) in comparison to 0-ACP (3.9 (3.4-4.1) GPa) and Ba-ACP (4.6 (4.2-6.9) GPa). Ion release kinetics was not affected by the addition of inert fillers to the ACP composites. Significance Incorporation of barium-glass fillers to the composition of ACP composites contributed to the improvement of flexural strength and modulus, with no adverse influence on ion release profiles. © 2014 Academy of Dental Materials. Source

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