151
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Lee WT, Tong X, Pierce J, Fleenor M, Ismaili A, Robertson JL, Chen WC, Gentile TR, Hailemariam A, Goyette R, Parizzi A, Lauter V, Klose F, Kaiser H, Lavelle C, Baxter DV, Jones GL, Wexler J, McCollum L. In-situ Polarized3He-Based Neutron Polarization Analyzer for SNS Magnetism Reflectometer. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/251/1/012086] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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152
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Xiong Y, Teegarden BR, Choi JSK, Strah-Pleynet S, Decaire M, Jayakumar H, Dosa PI, Casper MD, Pham L, Feichtinger K, Ullman B, Adams J, Yuskin D, Frazer J, Morgan M, Sadeque A, Chen W, Webb RR, Connolly DT, Semple G, Al-Shamma H. Discovery and structure-activity relationship of 3-methoxy-N-(3-(1-methyl-1H-pyrazol-5-yl)-4-(2-morpholinoethoxy)phenyl)benzamide (APD791): a highly selective 5-hydroxytryptamine2A receptor inverse agonist for the treatment of arterial thrombosis. J Med Chem 2010; 53:4412-21. [PMID: 20455563 DOI: 10.1021/jm100044a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Serotonin, which is stored in platelets and is released during thrombosis, activates platelets via the 5-HT(2A) receptor. 5-HT(2A) receptor inverse agonists thus represent a potential new class of antithrombotic agents. Our medicinal program began with known compounds that displayed binding affinity for the recombinant 5-HT(2A) receptor, but which had poor activity when tested in human plasma platelet inhibition assays. We herein describe a series of phenyl pyrazole inverse agonists optimized for selectivity, aqueous solubility, antiplatelet activity, low hERG activity, and good pharmacokinetic properties, resulting in the discovery of 10k (APD791). 10k inhibited serotonin-amplified human platelet aggregation with an IC(50) = 8.7 nM and had negligible binding affinity for the closely related 5-HT(2B) and 5-HT(2C) receptors. 10k was orally bioavailable in rats, dogs, and monkeys and had an acceptable safety profile. As a result, 10k was selected further evaluation and advanced into clinical development as a potential treatment for arterial thrombosis.
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153
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Krycka KL, Booth RA, Hogg CR, Ijiri Y, Borchers JA, Chen WC, Watson SM, Laver M, Gentile TR, Dedon LR, Harris S, Rhyne JJ, Majetich SA. Core-shell magnetic morphology of structurally uniform magnetite nanoparticles. PHYSICAL REVIEW LETTERS 2010; 104:207203. [PMID: 20867056 DOI: 10.1103/physrevlett.104.207203] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Indexed: 05/15/2023]
Abstract
A new development in small-angle neutron scattering with polarization analysis allows us to directly extract the average spatial distributions of magnetic moments and their correlations with three-dimensional directional sensitivity in any magnetic field. Applied to a collection of spherical magnetite nanoparticles 9.0 nm in diameter, this enhanced method reveals uniformly canted, magnetically active shells in a nominally saturating field of 1.2 T. The shell thickness depends on temperature, and it disappears altogether when the external field is removed, confirming that these canted nanoparticle shells are magnetic, rather than structural, in origin.
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154
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Zhang JH, Panicker LM, Seigneur EM, Lin L, House CD, Morgan W, Chen WC, Mehta H, Haj-Ali M, Yu ZX, Simonds WF. Cytoplasmic polyadenylation element binding protein is a conserved target of tumor suppressor HRPT2/CDC73. Cell Death Differ 2010; 17:1551-65. [PMID: 20339377 DOI: 10.1038/cdd.2010.32] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Parafibromin, a tumor suppressor protein encoded by HRPT2/CDC73 and implicated in parathyroid cancer and the hyperparathyroidism-jaw tumor (HPT-JT) familial cancer syndrome, is part of the PAF1 transcriptional regulatory complex. Parafibromin has been implicated in apoptosis and growth arrest, but the mechanism by which its loss of function promotes neoplasia is poorly understood. In this study we report that a hypomorphic allele of hyrax (hyx), the Drosophila homolog of HRPT2/CDC73, rescues the loss-of-ventral-eye phenotype of lobe (Akt1s1). Such rescue is consistent with previous reports that hyx/parafibromin is required for the nuclear transduction of Wingless (Wg)/Wnt signals and that Wg signaling antagonizes lobe function. A screen using double hyx/lobe heterozygotes identified an additional interaction with orb and orb2, the homologs of mammalian cytoplasmic polyadenylation element binding protein (CPEB), a translational regulatory protein. Hyx and orb2 heterozygotes lived longer and were more resistant to starvation than controls. In mammalian cells, knockdown of parafibromin expression reduced levels of CPEB1. Chromatin immunoprecipitation (ChIP) showed occupancy of CPEB1 by endogenous parafibromin. Bioinformatic analysis revealed a significant overlap between human transcripts potentially regulated by parafibromin and CPEB. These results show that parafibromin may exert both transcriptional and, through CPEB, translational control over a subset of target genes and that loss of parafibromin (and CPEB) function may promote tumorigenesis in part by conferring resistance to nutritional stress.
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155
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Dalvie D, Zhang C, Chen W, Smolarek T, Obach RS, Loi CM. Cross-Species Comparison of the Metabolism and Excretion of Zoniporide: Contribution of Aldehyde Oxidase to Interspecies Differences. Drug Metab Dispos 2009; 38:641-54. [DOI: 10.1124/dmd.109.030783] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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156
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Reger TS, Zunic J, Stock N, Wang B, Smith ND, Munoz B, Green MD, Gardner MF, James JP, Chen W, Alves K, Si Q, Treonze KM, Lingham RB, Mumford RA. Heterocycle-substituted proline dipeptides as potent VLA-4 antagonists. Bioorg Med Chem Lett 2009; 20:1173-6. [PMID: 20022493 DOI: 10.1016/j.bmcl.2009.12.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Revised: 12/01/2009] [Accepted: 12/02/2009] [Indexed: 11/17/2022]
Abstract
A variety of N-linked tertiary amines and heteroarylamines were examined at the 4-position of sulfonylated proline dipeptides in order to improve VLA-4 receptor off-rates and overcome the issue of CYP3A4 time-dependent inhibition of ester prodrugs. A tight-binding inhibitor 5j with a long off-rate provided sustained receptor occupancy despite poor oral pharmacokinetics.
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157
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Cabrera I, Kenzelmann M, Lawes G, Chen Y, Chen WC, Erwin R, Gentile TR, Leão JB, Lynn JW, Rogado N, Cava RJ, Broholm C. Coupled magnetic and ferroelectric domains in multiferroic Ni3V2O8. PHYSICAL REVIEW LETTERS 2009; 103:087201. [PMID: 19792753 DOI: 10.1103/physrevlett.103.087201] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2009] [Indexed: 05/28/2023]
Abstract
Electric control of multiferroic domains is demonstrated through polarized magnetic neutron diffraction. Cooling to the cycloidal multiferroic phase of Ni3V2O8 in an electric field E causes the incommensurate Bragg reflections to become neutron spin polarizing, the sense of neutron polarization reversing with E. Quantitative analysis indicates the E-treated sample has a handedness that can be reversed by E. We further show a close association between cycloidal and ferroelectric domains through E-driven spin and electric polarization hysteresis. We suggest that a definite cycloidal handedness is achieved through magnetoelastically induced Dzyaloshinskii-Moriya interactions.
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158
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Kuo LN, Huang CJ, Fang YC, Huang CC, Wang JL, Lin KL, Chu ST, Chang HT, Chien JM, Su HH, Chi CC, Chen WC, Tsai JY, Liao WC, Tseng LL, Jan CR. Effect of thimerosal on Ca2+ movement and viability in human oral cancer cells. Hum Exp Toxicol 2009; 28:301-8. [DOI: 10.1177/0960327109106548] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The effect of thimerosal on cytosolic free Ca2+ concentrations ([Ca2+]i ) in human oral cancer cells (OC2) is unclear. This study explored whether thimerosal changed basal [Ca2+]i levels in suspended OC2 cells using fura-2. Thimerosal at concentrations between 1and 50 μM increased [Ca2+]i in a concentration-dependent manner. The Ca2+ signal was reduced partly by removing extracellular Ca 2+. Thimerosal-induced Ca2+ influx was not blocked by L-type Ca2+ entry inhibitors and protein kinase C modulators (phorbol 12-myristate 13-acetate [PMA] and GF109203X). In Ca2+-free medium, 50 μM thimerosal failed to induce a [Ca2+]i rise after pretreatment with thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor). Inhibition of phospholipase C with U73122 did not change thimerosal-induced [Ca2+]i rises. At concentrations between 5 and 10 μM, thimerosal killed cells in a concentration-dependent manner. The cytotoxic effect of 8 μM thimerosal was potentiated by prechelating cytosolic Ca2+ with the Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetate/acetomethyl (BAPTA/ AM). Flow cytometry data suggested that 1—7 μM thimerosal-induced apoptosis in a concentration-dependent manner. Collectively, in OC2 cells, thimerosal-induced [Ca2+]i rises by causing phospholipase C-independent Ca2+ release from the endoplasmic reticulum and Ca2+ influx through non—L-type Ca2+ channels. Thimerosal killed cells in a concentration-dependent manner through apoptosis.
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159
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Adams JW, Ramirez J, Shi Y, Thomsen W, Frazer J, Morgan M, Edwards JE, Chen W, Teegarden BR, Xiong Y, Al-Shamma H, Behan DP, Connolly DT. APD791, 3-methoxy-n-(3-(1-methyl-1h-pyrazol-5-yl)-4-(2-morpholinoethoxy)phenyl)benzamide, a novel 5-hydroxytryptamine 2A receptor antagonist: pharmacological profile, pharmacokinetics, platelet activity and vascular biology. J Pharmacol Exp Ther 2009; 331:96-103. [PMID: 19628629 DOI: 10.1124/jpet.109.153189] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We have evaluated the receptor pharmacology, antiplatelet activity, and vascular pharmacology of APD791 [3-methoxy-N-(3-(1-methyl-1H-pyrazol-5-yl)-4-(2-morpholinoethoxy)phenyl)benzamide] a novel 5-hydroxytryptamine 2A (5-HT(2A)) receptor antagonist. APD791 displayed high-affinity binding to membranes (K(i) = 4.9 nM) and functional inverse agonism of inositol phosphate accumulation (IC(50) = 5.2 nM) in human embryonic kidney cells stably expressing the human 5-HT(2A) receptor. In competition binding assays, APD791 was greater than 2000-fold selective for the 5-HT(2A) receptor versus 5-HT(2C) and 5-HT(2B) receptors, and was inactive when tested against a wide panel of other G-protein-coupled receptors. APD791 inhibited 5-HT-mediated amplification of ADP-stimulated human and dog platelet aggregation (IC(50) = 8.7 and 23.1 nM, respectively). Similar potency was observed for inhibition of 5-HT-stimulated DNA synthesis in rabbit aortic smooth muscle cells (IC(50) = 13 nM) and 5-HT-mediated vasoconstriction in rabbit aortic rings. Oral administration of APD791 to dogs resulted in acute (1-h) and subchronic (10-day) inhibition of 5-HT-mediated amplification of collagen-stimulated platelet aggregation in whole blood. Two active metabolites, APD791-M1 and APD791-M2, were generated upon incubation of APD791 with human liver microsomes and were also indentified in dogs after oral administration of APD791. The affinity and selectivity profiles of both metabolites were similar to APD791. These results demonstrate that APD791 is an orally available, high-affinity 5-HT(2A) receptor antagonist with potent activity on platelets and vascular smooth muscle.
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160
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Yen JH, Liao WC, Chen WC, Wang YS. Interaction of polybrominated diphenyl ethers (PBDEs) with anaerobic mixed bacterial cultures isolated from river sediment. JOURNAL OF HAZARDOUS MATERIALS 2009; 165:518-524. [PMID: 19019534 DOI: 10.1016/j.jhazmat.2008.10.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Revised: 10/06/2008] [Accepted: 10/06/2008] [Indexed: 05/27/2023]
Abstract
The degradation of flame retardant polybrominated diphenyl ethers (PBDE), including tetra-brominated diphenyl ether (BDE-47), penta-brominated diphenyl ether (BDE-99 and -100), and hexa-brominated diphenyl ether (BDE-153 and -154), by anaerobic bacterial mixed cultures isolated from river sediment was investigated. The effects of PBDEs on changes of anaerobic bacterial community in sediment culture were also studied. Sediments were collected from Er-Jen River and Nan-Kan River basins, which were both heavily polluted rivers in Taiwan, and bacteria from the sediment samples were enriched before the experiment was conducted. Into the anaerobic bacterial mixed cultures, 0.1 microg/mL of PBDEs was added followed by incubation under 30 degrees C for 70 days. Residues of PBDE were determined by gas chromatography with electron capture detector (GC-ECD), and the changes of bacterial community were analyzed by denaturing gradient gel electrophoresis (DGGE). Less than 20% of PBDEs were degraded after 70 days of incubation in all samples except for BDE-47 from the Nan-Kan River sediment. In that culture, BDE-47 was found to have notably degraded. In particular, after 42 days of incubation; BDE-47 was degraded, suddenly and sharply, to a negligible level on Day 70, and the result was confirmed by a repeated experiment. An interesting result was that although BDE-47 was degraded fast in the Nan-Kan River sediment, the bacterial communities did not shift significantly as we had speculated at Day 70. From UPGMA dendrograms, PBDEs changed the composition of bacterial communities, and the extents varied with the variety of PBDE congeners. By the amendment with BDE-153 or -154, bacterial communities would be changed immediately and irreversibly throughout the rest of the incubation period. No significant difference in degradation of PBDEs was observed between sediment bacteria from Er-Jen River and Nan-Kan River. However, the results verified the persistence of PBDEs in the environment.
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161
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McIver JW, Erwin R, Chen WC, Gentile TR. End-compensated magnetostatic cavity for polarized 3He neutron spin filters. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2009; 80:063905. [PMID: 19566213 DOI: 10.1063/1.3154386] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We have expanded upon the "Magic Box" concept, a coil driven magnetic parallel plate capacitor constructed out of mu-metal, by introducing compensation sections at the ends of the box that are tuned to limit end-effects similar to those of short solenoids. This ability has reduced the length of the magic box design without sacrificing any loss in field homogeneity, making the device far more applicable to the often space limited neutron beam line. The appeal of the design beyond affording longer polarized 3He lifetimes is that it provides a vertical guide field, which facilitates neutron spin transport for typical polarized beam experiments. We have constructed two end-compensated magic boxes of dimensions 28.4 x 40 x 15 cm3 (length x width x height) with measured, normalized volume-averaged transverse field gradients ranging from 3.3 x 10(-4) to 6.3 x 10(-4) cm(-1) for cell sizes ranging from 8.1 x 6.0 to 12.0 x 7.9 cm2 (diameter x length), respectively.
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162
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Huber MG, Arif M, Black TC, Chen WC, Gentile TR, Hussey DS, Pushin DA, Wietfeldt FE, Yang L. Precision measurement of the n-3He incoherent scattering length using neutron interferometry. PHYSICAL REVIEW LETTERS 2009; 102:200401. [PMID: 19519009 DOI: 10.1103/physrevlett.102.200401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Revised: 02/19/2009] [Indexed: 05/27/2023]
Abstract
We report the first measurement of the low-energy neutron-(3)He incoherent scattering length using neutron interferometry: b_{i};{'} = (-2.512 +/- 0.012 stat +/- 0.014 syst) fm. This is in good agreement with a recent calculation using the AV18 + 3N potential. The neutron-(3)He scattering lengths are important for testing and developing nuclear potential models that include three-nucleon forces, effective field theories for few-body nuclear systems, and neutron scattering measurements of quantum excitations in liquid helium. This work demonstrates the first use of a polarized nuclear target in a neutron interferometer.
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163
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Wang JL, Lin KL, Chen WC, Chou CT, Huang CJ, Liu CS, Hsieh CH, Chang CH, Huang JK, Chang HT, Liu SI, Hsu SS, Jan CR. Effect of Celecoxib on Ca2+Fluxes and Proliferation in MDCK Renal Tubular Cells. J Recept Signal Transduct Res 2008; 25:237-49. [PMID: 16393914 DOI: 10.1080/10799890500464704] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The effect of celecoxib on renal tubular cells is largely unexplored. In Madin Darby canine kidney (MDCK) cells, the effect of celecoxib on intracellular CaCa2+ concentration ([Ca2+]i) and proliferation was examined by using the Ca(2 +)-sensitive fluorescent dye fura-2 and the viability detecting fluorescent dye tetrazolium, respectively. Celecoxib (> or =1 micro M) caused an increase of [CaCa2+]i in a concentration-dependent manner. Celecoxib-induced [CaCa2+]i increase was partly reduced by removal of extracellular CaCa2+. Celecoxib-induced CaCa2+ influx was independently suggested by MnCa2+ influx-induced fura-2 fluorescence quench. In Ca(2 +)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2 +)-ATPase, caused a monophasic [CaCa2+]i increase, after which celecoxib only induced a tiny [CaCa2+]i increase; conversely, pretreatment with celecoxib completely inhibited thapsigargin-induced [CaCa2+]i increases. U73122, an inhibitor of phospholipase C, abolished ATP (but not celecoxib)-induced [CaCa2+]i increases. Overnight incubation with 1 or 10 micro M celecoxib decreased cell viability by 80% and 100%, respectively. These data indicate that celecoxib evokes a [CaCa2+]i increase in renal tubular cells by stimulating both extracellular CaCa2+ influx and intracellular CaCa2+ release and is highly toxic to renal tubular cells in vitro.
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164
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Chang HC, Cheng HH, Huang CJ, Chen WC, Chen IS, Liu SI, Hsu SS, Chang HT, Wang JK, Lu YC, Chou CT, Jan CR. Safrole-Induced Ca2+Mobilization and Cytotoxicity in Human PC3 Prostate Cancer Cells. J Recept Signal Transduct Res 2008; 26:199-212. [PMID: 16777715 DOI: 10.1080/10799890600662595] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The effect of the carcinogen safrole on intracellular Ca2+ mobilization and on viability of human PC3 prostate cancer cells was examined. Cytosolic free Ca2+ levels ([Ca2+]i) were measured by using fura-2 as a probe. Safrole at concentrations above 10 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 350 microM. The Ca2+ signal was reduced by more than half after removing extracellular Ca2+ but was unaffected by nifedipine, nicardipine, nimodipine, diltiazem, or verapamil. In Ca2+-free medium, after treatment with 650 microM safrole, 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) failed to release Ca2+. Neither inhibition of phospholipase C with U73122 nor modulation of protein kinase C activity affected safrole-induced Ca2+ release. Overnight incubation with 0.65-65 microM safrole did not affect cell viability, but incubation with 325-625 microM safrole decreased viability. Collectively, the data suggest that in PC3 cells, safrole induced a [Ca2+]i increase by causing Ca2+ release from the endoplasmic reticulum in a phospholipase C- and protein kinase C-independent fashion, and by inducing Ca2+ influx. Safrole can decrease cell viability in a concentration-dependent manner.
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165
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Sharma M, Babcock E, Andersen KH, Barrón-Palos L, Becker M, Boag S, Chen WC, Chupp TE, Danagoulian A, Gentile TR, Klein A, Penttila S, Petoukhov A, Soldner T, Tardiff ER, Walker TG, Wilburn WS. Neutron beam effects on spin-exchange-polarized 3He. PHYSICAL REVIEW LETTERS 2008; 101:083002. [PMID: 18764610 DOI: 10.1103/physrevlett.101.083002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Indexed: 05/26/2023]
Abstract
We have observed depolarization effects when high intensity cold neutron beams are incident on alkali-metal spin-exchange-polarized 3He cells used as neutron spin filters. This was first observed as a reduction of the maximum attainable 3He polarization and was attributed to a decrease of alkali-metal polarization, which led us to directly measure alkali-metal polarization and spin relaxation over a range of neutron fluxes at Los Alamos Neutron Science Center and Institute Laue-Langevin. The data reveal a new alkali-metal spin-relaxation mechanism that approximately scales as sqrt[phi_{n}], where phi_{n} is the neutron capture-flux density incident on the cell. This is consistent with an effect proportional to the concentration of electron-ion pairs but is much larger than expected from earlier work.
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166
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Dalvie D, Chen W, Zhang C, Vaz AD, Smolarek TA, Cox LM, Lin J, Obach RS. Pharmacokinetics, Metabolism, and Excretion of Torcetrapib, a Cholesteryl Ester Transfer Protein Inhibitor, in Humans. Drug Metab Dispos 2008; 36:2185-98. [DOI: 10.1124/dmd.108.023176] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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167
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Tsai WL, Cheng JS, Lai KH, Lin CP, Lo GH, Hsu PI, Yu HC, Lin CK, Chan HH, Chen WC, Chen TA, Li WL, Liang HL. Clinical trial: percutaneous acetic acid injection vs. percutaneous ethanol injection for small hepatocellular carcinoma--a long-term follow-up study. Aliment Pharmacol Ther 2008; 28:304-11. [PMID: 19086330 DOI: 10.1111/j.1365-2036.2008.03702.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND The long-term outcome of percutaneous acetic acid injection (PAI) and percutaneous ethanol injection (PEI) for treating small hepatocellular carcinoma (HCC) remains unclear. AIM To compare the long-term outcome of PAI vs. PEI for treating small HCC. METHODS From July 1998 to July 2004, 125 patients with small HCC were enrolled. Seventy patients receiving PAI and 55 patients receiving PEI were enrolled. There were no significant differences in the clinical characteristics between the two groups. Tumour recurrence and survival rates were assessed. RESULTS Mean follow-up time was 43 months. The local recurrence rate and new tumour recurrence rate were similar between the PAI and PEI groups. The PAI group had significantly better survival than the PEI group (P = 0.027). Multivariate analysis revealed that PAI was the significant factor associated with overall survival [PAI vs. PEI, RR: 0.639, 95% CI: (0.419-1.975), P = 0.038]. The treatment sessions required to achieve complete tumour necrosis were significantly fewer in the PAI group than in the PEI group (2.4 +/- 1.0 vs. 2.9 +/- 1.3, P = 0.018). CONCLUSION Percutaneous acetic acid injection required fewer treatment sessions than PEI and provided better survival after long-term follow-up.
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168
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Prakash C, Chen W, Rossulek M, Johnson K, Zhang C, O'Connell T, Potchoiba M, Dalvie D. Metabolism, Pharmacokinetics, and Excretion of a Cholesteryl Ester Transfer Protein Inhibitor, Torcetrapib, in Rats, Monkeys, and Mice: Characterization of Unusual and Novel Metabolites by High-Resolution Liquid Chromatography-Tandem Mass Spectrometry and1H Nuclear Magnetic Resonance. Drug Metab Dispos 2008; 36:2064-79. [DOI: 10.1124/dmd.108.022277] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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169
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Liu SI, Cheng HH, Huang CJ, Chang HC, Chen WC, Chen IS, Hsu SS, Chang HT, Huang JK, Chen JS, Lu YC, Jan CR. Melittin-induced [Ca2+]i increases and subsequent death in canine renal tubular cells. Hum Exp Toxicol 2008; 27:417-24. [DOI: 10.1177/0960327108094606] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The effect of melittin on cytosolic free Ca2+ concentration ([Ca2+]i) and viability is largely unknown. This study examined whether melittin alters Ca2+ levels and causes Ca2+-dependent cell death in Madin-Darby canine kidney (MDCK) cells. [Ca2+]i and cell death were measured using the fluorescent dyes fura-2 and WST-1 respectively. Melittin at concentrations above 0.5 μM increased [Ca2+]i in a concentration-dependent manner. The Ca2+ signal was reduced by 75% by removing extracellular Ca2+. The melittin-induced Ca2+ influx was also implicated by melittin-caused Mn2+ influx. After pretreatment with 1 μM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), melittin-induced Ca2+ release was inhibited; and conversely, melittin pretreatment abolished thapsigargin-induced Ca2+ release. At concentrations of 0.5–20 μM, melittin killed cells in a concentration-dependent manner. The cytotoxic effect of 0.5 μM melittin was nearly completely reversed by prechelating cytosolic Ca2+ with BAPTA. Melittin at 0.5–2 μM caused apoptosis as assessed by flow cytometry of propidium iodide staining. Collectively, in MDCK cells, melittin induced a [Ca2+]i rise by causing Ca2+ release from endoplasmic reticulum and Ca2+ influx from extracellular space. Furthermore, melittin can cause Ca2+-dependent cytotoxicity in a concentration-dependent manner.
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170
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Thomsen WJ, Grottick AJ, Menzaghi F, Reyes-Saldana H, Espitia S, Yuskin D, Whelan K, Martin M, Morgan M, Chen W, Al-Shamma H, Smith B, Chalmers D, Behan D. Lorcaserin, a novel selective human 5-hydroxytryptamine2C agonist: in vitro and in vivo pharmacological characterization. J Pharmacol Exp Ther 2008; 325:577-87. [PMID: 18252809 DOI: 10.1124/jpet.107.133348] [Citation(s) in RCA: 310] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
5-Hydroxytryptamine (5-HT)(2C) receptor agonists hold promise for the treatment of obesity. In this study, we describe the in vitro and in vivo characteristics of lorcaserin [(1R)-8-chloro-2,3,4,5-tetrahydro-1-methyl-1H-3 benzazepine], a selective, high affinity 5-HT(2C) full agonist. Lorcaserin bound to human and rat 5-HT(2C) receptors with high affinity (K(i) = 15 +/- 1 nM, 29 +/- 7 nM, respectively), and it was a full agonist for the human 5-HT(2C) receptor in a functional inositol phosphate accumulation assay, with 18- and 104-fold selectivity over 5-HT(2A) and 5-HT(2B) receptors, respectively. Lorcaserin was also highly selective for human 5-HT(2C) over other human 5-HT receptors (5-HT(1A), 5-HT(3), 5-HT(4C), 5-HT5(5A), 5-HT(6), and 5-HT(7)), in addition to a panel of 67 other G protein-coupled receptors and ion channels. Lorcaserin did not compete for binding of ligands to serotonin, dopamine, and norepinephrine transporters, and it did not alter their function in vitro. Behavioral observations indicated that unlike the 5-HT(2A) agonist (+/-)-1-(2,5-dimethoxy-4-phenyl)-2-aminopropane, lorcaserin did not induce behavioral changes indicative of functional 5-HT(2A) agonist activity. Acutely, lorcaserin reduced food intake in rats, an effect that was reversed by pretreatment with the 5-HT(2C)-selective antagonist 6-chloro-5-methyl-1-[6-(2-methylpyridin-3-yloxy)pyridin-3-yl-carbamoyl]indoline (SB242,084) but not the 5-HT(2A) antagonist (R)-(+)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenylethyl)]-4-piperidine-methanol (MDL 100,907), demonstrating mediation by the 5-HT(2C) receptor. Chronic daily treatment with lorcaserin to rats maintained on a high fat diet produced dose-dependent reductions in food intake and body weight gain that were maintained during the 4-week study. Upon discontinuation, body weight returned to control levels. These data demonstrate lorcaserin to be a potent, selective, and efficacious agonist of the 5-HT(2C) receptor, with potential for the treatment of obesity.
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171
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Chen TC, Lin YT, Lin CY, Chen WC, Chen MR, Kao HL, Chyi JI, Hsu CH. Suitability of surface acoustic wave oscillators fabricated using low temperature-grown AlN films on GaN/sapphire as UV sensors. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2008; 55:489-493. [PMID: 18334354 DOI: 10.1109/tuffc.2008.666] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Epitaxial AlN films were prepared on GaN/sapphire using a helicon sputtering system at the low temperature of 300 degrees C. Surface acoustic wave (SAW) devices fabricated on AlN/GaN/sapphire exhibited superior characteristics compared with those made on GaN/sapphire. An oscillator using an AlN/GaN/sapphirebased SAW device is presented. The oscillation frequency decreased when the device was illuminated by ultraviolet (UV) radiation, and the downshift of the oscillation frequency increased with the illuminating UV power density. The results showed that the AlN/GaN/sapphire-layered structure SAW oscillators are suitable for visible blind UV detection and opened up the feasibility of developing remote UV sensors for different ranges of wavelengths on the III-nitrides.
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172
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Campbell KHS, Fisher P, Chen WC, Choi I, Kelly RDW, Lee JH, Xhu J. Somatic cell nuclear transfer: Past, present and future perspectives. Theriogenology 2007; 68 Suppl 1:S214-31. [PMID: 17610946 DOI: 10.1016/j.theriogenology.2007.05.059] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
It is now over a decade since the birth, in 1996, of Dolly the first animal to be produced by nuclear transfer using an adult derived somatic cell as nuclear donor. Since this time similar techniques have been successfully applied to a range of species producing live offspring and allowing the development of transgenic technologies for agricultural, biotechnological and medical uses. However, though applicable to a range of species, overall, the efficiencies of development of healthy offspring remain low. The low frequency of successful development has been attributed to incomplete or inappropriate reprogramming of the transferred nuclear genome. Many studies have demonstrated that such reprogramming occurs by epigenetic mechanisms not involving alterations in DNA sequence, however, at present the molecular mechanisms underlying reprogramming are poorly defined. Since the birth of Dolly many studies have attempted to improve the frequency of development, this review will discuss the process of animal production by nuclear transfer and in particular changes in the methodology which have increased development and survival, simplified or increased robustness of the technique. Although much of the discussion is applicable across species, for simplicity we will concentrate primarily on published data for cattle, sheep, pigs and mice.
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173
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Chou MM, Hwang JI, Tseng JJ, Chen WC, Hung SW, Ho ESC. Diagnosis of an asymptomatic uterine rupture in a twin pregnancy with four-dimensional ultrasound examination and magnetic resonance imaging. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2007; 30:364-6. [PMID: 17654636 DOI: 10.1002/uog.4089] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
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174
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Chen WC, Ju CP, Chern Lin JH. Variation in structure and properties of a non-dispersive TTCP/DCPA-derived CPC immersed in Hanks? solution. J Oral Rehabil 2007; 34:541-51. [PMID: 17559622 DOI: 10.1111/j.1365-2842.2003.01207.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The present work is to characterize a non-dispersive, fast-setting and high-strength tetra calcium phosphate (TTCP)/dicalcium phosphate anhydrous (DCPA)-based calcium phosphate cement (nd-CPC) recently developed in the authors' laboratory. Comparison between this CPC and a conventional TTCP/DCPA-based CPC (c-CPC) is made. The results show that, during setting c-CPC reaches its pH plateau after 10 min, while nd-CPC approaches plateau after 20 min. During immersion in Hanks' solution the pH values of both cements reach their maxima after immersion for a few days, then decline eventually to near neutrality. With immersion time TTCP and DCPA phases gradually dissolve and apatite phase precipitates. The nd-CPC has a higher apatite formation rate and denser structure than c-CPC under similar conditions, especially at early stage. The nd-CPC also demonstrates higher strength both during setting and after immersion.
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175
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Tseng CC, Huang JJ, Wang MC, Wu AB, Ko WC, Chen WC, Wu JJ. PapG II adhesin in the establishment and persistence of Escherichia coli infection in mouse kidneys. Kidney Int 2007; 71:764-70. [PMID: 17290293 DOI: 10.1038/sj.ki.5002111] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Most human pyelonephritogenic Escherichia coli express the PapG II adhesin. However, the role of the PapG II adhesin in enhancing the establishment and persistence of E. coli infection in the kidney is controversial. A pyelonephritogenic strain, EC114, which possesses one copy of the papG II gene, but without other virulence factors (such as S/F1C-fimbriae, hemolysin, and cytotoxic necrotizing factor 1) was selected for the construction of a papG II mutant. The resulting papG II mutant was confirmed by polymerase chain reaction, Southern hybridization, and agglutination assay, and designated as MEC114. We compared MEC114 with the parental strain (EC114) for colonization ability in the bladder and kidney of female BALB/c mice, which were challenged transurethrally with 50 microl of a low (5x10(4) CFU (colony-forming unit)) or high (5x10(8) CFU) dose of EC114 or MEC114 and assessed 1, 3, and 7 days after inoculation. Geometric means of quantitative bacterial counts in the kidney were significantly decreased when challenged with MEC114 on day 3 after inoculation, at both low and high dose (P<0.05), as compared with EC114. On the seventh day, both strains were mainly cleared from the kidney. Renal biopsy showed a similar degree of inflammatory response to both strains 1, 3, and 7 days after inoculation. In brief, the PapG II adhesin can enhance the early establishment of E. coli infection in the kidney, but the bacteria do not maintain infection owing to the host immune response.
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