Publications by authors named "Son A"

Elevated KRAS expression has been frequently associated with cancer progression including breast cancer; however, therapeutic approaches targeting KRAS have been widely unsuccessful and KRAS mutant cancers remain unsolved problem in cancer therapy. In this study, we found that a new 2-pyrone derivative, 5-bromo-3-(3-hydroxyprop-1-ynyl)-2H-pyran-2-one (BHP) can block KRAS-driven breast cancer progression. Importantly, treatment with BHP effectively suppressed the migratory and invasive properties along with epithelial-mesenchymal transition (EMT) in MDA-MB231 breast cancer cells that carry oncogenic KRAS and mesenchymal malignant phenotypes.

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Cryosectioning, the sectioning of frozen specimens, has been an important histological tool for more than a century and continues to be extensively utilized today. However, the ability to produce high-quality sections is often a difficult process requiring extensive patience and experience. In this chapter, we have detailed an effective method for the embedding, mounting, and sectioning of frozen tissues, as well as have provided suggestions in producing high-quality sections.

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Growth cone collapse is an easy and efficient test for detecting and characterizing axon guidance activities secreted or expressed by cells. It can also be used to dissect signaling pathways by axon growth inhibitors and to isolate therapeutic compounds that promote axon regeneration. Here, we describe a growth cone collapse assay protocol used to study signal transduction mechanisms of the repulsive axon guidance molecule ephrin-A5 in hippocampal neurons.

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Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK), a TNF superfamily member, induces damage of the epithelial cells (ECs) and production of inflammatory mediaters through its receptor Fn14 in a model of acute colitis. In our current study of chronic colitis induced by repeated rectal injection of a hapten, we found that inflammation, fibrosis, and T helper 2 (Th2)-type immunity were significantly reduced in Fn14 gene knockout (KO) mice when compared with wild-type (WT) control mice. Expression of thymic stromal lymphopoietin (TSLP) was lower in Fn14 KO colon ECs than in WT ECs.

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Purpose: The cells of the mammalian lens must be carefully organized and regulated to maintain clarity. Recent studies have identified the Eph receptor ligand ephrin-A5 as a major contributor to lens development, as mice lacking ephrin-A5 develop abnormal lenses, resulting in cataracts. As a follow-up to our previous study on the cataracts observed in ephrin-A5(-/-) animals, we have further examined the morphological and molecular changes in the ephrin-A5(-/-) lens.

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Many of the available prediction equations for feed energy value may not be applicable for ingredients such as copra (Cocos nucifera) meal (CM), palm kernel meal (PKM), and cassava (Manihot esculenta) root (CR). Therefore, we developed novel equations for estimating GE and DE concentrations in CM, PKM, CR, and diets containing these ingredients. Data for GE and DE concentrations were obtained from previous experiments in which the chemical composition in the ingredients and diets were determined.

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An experiment was conducted to measure DE and ME in copra (Cocos nucifera) meal (CM), palm kernel meal (PKM), and cassava (Manihot esculenta) root (CR) in growing pigs. Eight boars with an initial BW of 67.3 ± 5.

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The phosphorescence emission of ruthenium complexes was applied to the optical imaging of physiological hypoxia. We prepared three complexes with hydrophobic substituents on the phenanthroline ligand and characterized their emission, which was quenched by molecular oxygen. Among the complexes synthesized in this study, a pyrene chromophore-linked ruthenium complex, Ru-Py, exhibited optimal properties for the imaging of hypoxia; the prolonged lifetime of the triplet excited state of the ruthenium chromophore, which was induced by efficient energy distribution and transfer from the pyrene unit, provided the highest sensitivity towards molecular oxygen.

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The Eph family of receptor tyrosine kinases (RTKs) has been implicated in the regulation of many aspects of mammalian development. Recent analyses have revealed that the EphA2 receptor is a key modulator for a wide variety of cellular functions. This review focuses on the roles of EphA2 in both development and disease.

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Carbon nanotubes (CNTs) possess unique properties that have led to an increase in their research and usage for a wide variety of fields. This growing demand of CNTs poses a major public health risk given its unregulated release into the environment. Unfortunately there is a significant information gap on the actual quantity of CNTs in the environment due to limitation of existing detection methods.

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In the processes of protein synthesis and folding, newly synthesized polypeptides are tightly connected to the macromolecules, such as ribosomes, lipid bilayers, or cotranslationally folded domains in multidomain proteins, representing a hallmark of de novo protein folding environments in vivo. Such linkage effects on the aggregation of endogenous polypeptides have been largely neglected, although all these macromolecules have been known to effectively and robustly solubilize their linked heterologous proteins in fusion or display technology. Thus, their roles in the aggregation of linked endogenous polypeptides need to be elucidated and incorporated into the mechanisms of de novo protein folding in vivo.

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Aims: Accumulating evidence indicates that oxidative stress is associated with inflammation, and the cellular redox status can determine the sensitivity and the final outcome in response to inflammatory stimuli. To control the redox balance, mammalian cells contain a variety of oxidoreductases belonging to the thioredoxin superfamily. The large number of these enzymes suggests a complex mechanism of redox regulation in mammals, but the precise function of each family member awaits further investigations.

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Cataract is the single largest contributor to blindness in the world, with the disease having a strong genetic component. In recent years the Eph family of receptor tyrosine kinases has been identified as a key regulator in lens clarity. In this review we discuss the roles of the Eph receptors in lens biology and cataract development.

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This research investigates the level and degradation of oil at ten selected Gulf saltmarsh sites months after the 2010 BP Macondo-1 well oil spill. Very high levels (10-28%) of organic carbon within the heavily oiled sediments are clearly distinguished from those in pristine sediments (<3%). Dissolved organic carbon in contaminated pore-waters, ranging up to hundreds of mg/kg, are 1 to 2 orders of magnitude higher than those at pristine sites.

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The cellular and molecular mechanisms underlying the pathogenesis of cataracts leading to visual impairment remain poorly understood. In recent studies, several mutations in the cytoplasmic sterile-α-motif (SAM) domain of human EPHA2 on chromosome 1p36 have been associated with hereditary cataracts in several families. Here, we have investigated how these SAM domain mutations affect EPHA2 activity.

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The receptor activator of NF-κB ligand (RANKL) signal is an activator of tumor necrosis factor receptor-associated factor 6 (TRAF6), which leads to the activation of NF-κB and other signal transduction pathways essential for osteoclastogenesis, such as Ca(2+) signaling. However, the intracellular levels of inositol 1,4,5-trisphosphate (IP(3)) and IP(3)-mediated cellular function of RANKL during osteoclastogenesis are not known. In the present study, we determined the levels of IP(3) and evaluated IP(3)-mediated osteoclast differentiation and osteoclast activity by RANKL treatment of mouse leukemic macrophage cells (RAW 264.

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Novel methods for inducing chondrogenesis are critical for cartilage tissue engineering and regeneration. Here we show that the synthetic oleanane triterpenoids, CDDO-Imidazolide (CDDO-Im) and CDDO-Ethyl amide (CDDO-EA), at concentrations as low as 200 nM, induce chondrogenesis in organ cultures of newborn mouse calvaria. The cartilage phenotype was measured histologically with metachromatic toluidine blue staining for proteoglycans and by immunohistochemical staining for type II collagen.

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NanoGene assay is a magnetic bead and quantum dot nanoparticles based gene quantification assay. It relies on a set of probe and signaling probe DNAs to capture the target DNA via hybridization. We have demonstrated the inhibition resistance of the NanoGene assay using humic acids laden genomic DNA (gDNA).

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Background & Aims: TWEAK, a member of the tumor necrosis factor (TNF) superfamily, promotes intestinal epithelial cell injury and signals through the receptor Fn14 following irradiation-induced tissue damage and during development of colitis in mice. Interleukin (IL)-13, an effector of tissue damage in similar models, has been associated with the pathogenesis of ulcerative colitis (UC). We investigated interactions between TWEAK and IL-13 following mucosal damage in mice.

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We have demonstrated the preliminary results of the in situ monitoring capability of an inhibitor resistant gene quantification assay using magnetic bead (MB) and quantum dot (QD) nanoparticles (hereafter "MB-QD assay") for the detection of E. coli O157:H7 in environmental samples. The selectivity of the MB-QD assay was demonstrated via the discrimination of the target bacteria in the presence of nonspecific microbial populations.

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Anaerobic microbial mixed cultures demonstrated its ability to completely remove perchlorate in the presence of zero-valent iron. In order to understand the major microbial reaction in the iron-supported culture, community analysis comprising of microbial fatty acids and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) techniques was performed for perchlorate reducing cultures. Analysis of fatty acid methyl esters (FAMEs) and subsequent principal component analysis (PCA) showed clear distinctions not only between iron-supported perchlorate reducing culture and seed bacteria, but also among perchlorate-reducing cultures receiving different electron donors.

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The development and characterization of a magnetic bead (MB)-quantum dot (QD) nanoparticles based assay capable of quantifying pathogenic bacteria is presented here. The MB-QD assay operates by having a capturing probe DNA selectively linked to the signaling probe DNA via the target genomic DNA (gDNA) during DNA hybridization. The signaling probe DNA is labeled with fluorescent QD(565) which serves as a reporter.

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Objectives: Endotoxin triggers a reorganization of the energy metabolic pathway, including the promotion of fatty acid utilization to adapt to a high energy demand during endotoxemia. However, the factors responsible for the metabolic adaptation and characteristic pathologies resulting from defective utilization fatty acids during endotoxin response have not been fully clarified. The thioredoxin binding protein-2 (TBP-2) knockout (TBP-2) mouse is an animal model of fatty acid oxidation disorder.

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Background: Economic tools have been used in the past to predict the trends in plastic surgery procedures. Since 1992, U.S.

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A magnetic/luminescent nanoparticles (MLNPs) based DNA hybridization method was developed for quantitative monitoring of antibiotic resistance genes and gene-expression in environmental samples. Manipulation of magnetic field enabled the separation of the MLNPs-DNA hybrids from the solution and the fluorescence of MLNPs normalized the quantity of target DNA. In our newly developed MLNPs-DNA assay, linear standard curves (R(2) = 0.

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