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Zhang Z, Chen W, Khalid M, Zhou J, Xu L, Hong H. [Evaluation and fate of the organic chlorine pesticides at the waters in Jiulong River Estuary]. HUAN JING KE XUE= HUANJING KEXUE 2001; 22:88-92. [PMID: 11507915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
18 Organochlorine Pesticides at the water(surface water and porewater) in Jiulong River Estuary were determined. The range of organochlorine pesticides at surface water was 51.3-2479 ng/L, and the concentration in porewater was 266-33,355 ng/L. The results showed that the organochlorine pesticides were removed in the estuary and the sediments were the reservior of the organochlorine pesticides. Compared with the results of other harbor and estuaries, it showed that the contamination for organic chlorine pollutants in Jiulong River Estuary was similar to those of others. At the same time, the risk of organochlorine pesticides in the estuary was evaluated.
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327
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Holt M, Zschack P, Hong H, Chou MY, Chiang TC. X-ray studies of phonon softening in tise2. PHYSICAL REVIEW LETTERS 2001; 86:3799-3802. [PMID: 11329327 DOI: 10.1103/physrevlett.86.3799] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2000] [Indexed: 05/23/2023]
Abstract
The charge-density-wave transition in TiSe (2), which results in a commensurate (2x2x2) superlattice at temperatures below approximately 200 K, presumably involves softening of a zone-boundary phonon mode. For the first time, this phonon-softening behavior has been examined over a wide temperature range by synchrotron x-ray thermal diffuse scattering.
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328
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Hong H, Zhang W, Liu P, Zhu P. [Effect of recombinant epidermal growth factor on corneal epithelial cells after excision of pterygium]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 2001; 23:199-201. [PMID: 12905904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
OBJECTIVE To investigate the effects of recombinant epidermal growth factor on the wounded corneal healing after excision of pterygium. METHODS Simple and unrecurrent pterygium was selected, excised and sewed up conjunctival flap under local anaesthesia and microscope. After operation two drops of EGF eyedrop were used, and five minutes later 0.3% Tarivid Eye Oint was used again, and then the operated eye was enswathed. Everyday the wound cornea was observed and the EGF eyedrop was used. RESULTS The wound cornea healing time of control group was seven days and that of the EGF group was five days and gave a remarkable difference (P < 0.05). The same results were obtained after comparing the effective group and ineffective group, P < 0.05. CONCLUSIONS EGF eyedrop can accelerate proliferation and recovery of wound corneal epithelial cells. In the clinical trial, every body felt well and no side-effect was observed.
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329
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Sogawa H, Kawai T, Wee SL, Boskovic S, Nadazdin O, Phelan J, Abrahamian G, Ko DS, Hong H, Mauiyyedi S, Colvin RB, Sachs DH, Cosimi AB. Comparison of horse antithymocyte globulin with other T cell-depleting antibodies for induction of chimerism and renal allograft tolerance in nonhuman primates. Transplant Proc 2001; 33:116-7. [PMID: 11266735 DOI: 10.1016/s0041-1345(00)01933-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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330
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Qiu X, Reed DW, Hong H, MacKenzie SL, Covello PS. Identification and analysis of a gene from Calendula officinalis encoding a fatty acid conjugase. PLANT PHYSIOLOGY 2001; 125:847-855. [PMID: 11161042 PMCID: PMC64886 DOI: 10.1104/pp.125.2.847] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2000] [Revised: 07/20/2000] [Accepted: 10/12/2000] [Indexed: 05/23/2023]
Abstract
Two homologous cDNAs, CoFad2 and CoFac2, were isolated from a Calendula officinalis developing seed by a polymerase chain reaction-based cloning strategy. Both sequences share similarity to FAD2 desaturases and FAD2-related enzymes. In C. officinalis plants CoFad2 was expressed in all tissues tested, whereas CoFac2 expression was specific to developing seeds. Expression of CoFad2 cDNA in yeast (Saccharomyces cerevisiae) indicated it encodes a Delta12 desaturase that introduces a double bond at the 12 position of 16:1(9Z) and 18:1(9Z). Expression of CoFac2 in yeast revealed that the encoded enzyme acts as a fatty acid conjugase converting 18:2(9Z, 12Z) to calendic acid 18:3(8E, 10E, 12Z). The enzyme also has weak activity on the mono-unsaturates 16:1(9Z) and 18:1(9Z) producing compounds with the properties of 8,10 conjugated dienes.
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331
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Teng CL, Hong H, Kiihne S, Bryant RG. Molecular oxygen spin-lattice relaxation in solutions measured by proton magnetic relaxation dispersion. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2001; 148:31-34. [PMID: 11133273 DOI: 10.1006/jmre.2000.2219] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Proton spin-lattice relaxation rate constants have been measured as a function of magnetic field strength for water, water-glycerol solution, cyclohexane, methanol, benzene, acetone, acetonitrile, and dimethyl sulfoxide. The magnetic relaxation dispersion is well approximated by a Lorentzian shape. The origin of the relaxation dispersion is identified with the paramagnetic contribution from molecular oxygen. In the small molecule cases studied here, the effective correlation time for the electron-nuclear coupling may include contributions from both translational diffusion and the electron T(1). The electron T(1) for molecular oxygen dissolved in several solvents was found to be approximately 7.5 ps and nearly independent of solvent or viscosity.
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332
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Hong H, Choi MY. Phase synchronization and noise-induced resonance in systems of coupled oscillators. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 2000; 62:6462-6468. [PMID: 11101982 DOI: 10.1103/physreve.62.6462] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2000] [Revised: 06/23/2000] [Indexed: 05/23/2023]
Abstract
We study synchronization and noise-induced resonance phenomena in systems of globally coupled oscillators, each possessing finite inertia. The behavior of the order parameter, which measures the collective synchronization of the system, is investigated as the noise level and the coupling strength are varied, and hysteretic behavior is manifested. The power spectrum of the phase velocity is also examined and the quality factor as well as the response function is obtained to reveal noise-induced resonance behavior.
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333
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Huynh MH, Hong H, Delovitch S, Desser S, Ringuette M. Association of SPARC (osteonectin, BM-40) with extracellular and intracellular components of the ciliated surface ectoderm of Xenopus embryos. CELL MOTILITY AND THE CYTOSKELETON 2000; 47:154-62. [PMID: 11013395 DOI: 10.1002/1097-0169(200010)47:2<154::aid-cm6>3.0.co;2-l] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
SPARC (Secreted Protein, Acidic, Rich in Cysteine) was detected by immunohistochemistry in the sensorial layer of the bilayered embryonic epidermis of Xenopus laevis during neurulation, when a subset of the sensorial cells are selected to differentiate into ciliated cell precursors. After the ciliated cells had intercalated into the outer layer and had undergone ciliogenesis, intense SPARC immunostaining was associated with the cilia and remained associated with the cilia throughout their persistence on the epidermis. Circumferential SPARC immunostaining was also detected at the interface between surface epithelial cells. Animal cap explants indicated that the embryonic activation of SPARC expression in the dorsal ectoderm does not require signaling from factors secreted by the underlying mesoderm. Immunoelectron microscopy revealed that SPARC is intimately associated with the 9 + 2 microtubule arrays of cilia. Our data indicate that SPARC plays a role in the development and function of the surface ciliated epidermis of Xenopus embryos. We propose that the counter-adhesive activity of SPARC facilitates the intercalation of ciliary cell precursors to the surface epithelial layer, where its Ca(2+)-binding abilities promote cell-cell adhesion. Based on its association with ciliary microtubule arrays, we also propose that intracellular SPARC may play a role in regulating ciliary beat frequency and polarity.
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334
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Lee CH, Hong H, Shin J, Jung M, Shin I, Yoon J, Lee W. NMR studies on novel antitumor drug candidates, deoxoartemisinin and carboxypropyldeoxoartemisinin. Biochem Biophys Res Commun 2000; 274:359-69. [PMID: 10913344 DOI: 10.1006/bbrc.2000.3086] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Artemisinin and its derivatives, which have been known as antimalarial drugs, have also demonstrated their cytotoxicity against tumor cells. It has been proposed that antitumor activity depends on the lipophilicity of functional group on artemisinin derivatives. Solution structures of two artemisinin derivatives as antitumor drug candidates, deoxoartemisinin and carboxypropyldeoxoartemisinin, were determined by NMR spectroscopy to elucidate structure-activity relationship. According to biological assay, antitumor efficiencies are not dependent upon lipophilicity. Instead, these compounds demonstrated their distinctive structural features of boat/chair conformation and capability to interact with receptors, as they have different efficiencies on antitumor activity. Especially, carboxypropyl moiety or carbonyl moiety in artemisinin derivatives influences the conformation and stability of ring structure. Although the detailed mechanism of antitumor activity by artemisinin derivatives has not been addressed, we suggest that antitumor activity is not determined only with lipophilicity and that artemisinin derivatives have specific target proteins in each type of cancer.
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335
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Lee J, Kim D, Hong H, Han S, Kim J. Protective effect of etomidate on kainic acid-induced neurotoxicity in rat hippocampus. Neurosci Lett 2000; 286:179-82. [PMID: 10832014 DOI: 10.1016/s0304-3940(00)01118-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The goal of this study was to determine whether etomidate has protective effect against kainic acid (KA)-induced neurotoxicity. Administration of etomidate (20 mg/kg i.p.) was performed in sequence, first being just 1 h after KA (10 mg/kg i.p.) injection, then three times at 1-h intervals. Neuronal damages in hippocampus were evaluated by using the acid fuchsin stain to detect cell death and the heat shock protein-70 (HSP-70) induction as an index of cell injury at 24 h after the administration of KA. HSP-70 induction and acid fuchsin positive neurons were increased in CA1 and CA3 regions of hippocampus after KA injection but significantly decreased by etomidate-injection. These results suggest that the etomidate hold potential effect on the protection of neurons against KA-induced neurotoxicity.
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336
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Yang L, Guerrero J, Hong H, DeFranco DB, Stallcup MR. Interaction of the tau2 transcriptional activation domain of glucocorticoid receptor with a novel steroid receptor coactivator, Hic-5, which localizes to both focal adhesions and the nuclear matrix. Mol Biol Cell 2000; 11:2007-18. [PMID: 10848625 PMCID: PMC14899 DOI: 10.1091/mbc.11.6.2007] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Hic-5 (hydrogen peroxide-inducible clone-5) is a focal adhesion protein that is involved in cellular senescence. In the present study, a yeast two-hybrid screen identified Hic-5 as a protein that interacts with a region of the glucocorticoid receptor that includes a nuclear matrix-targeting signal and the tau2 transcriptional activation domain. In transiently transfected mammalian cells, overexpression of Hic-5 potentiated the activation of reporter genes by all steroid receptors, excluding the estrogen receptor. The activity of the estrogen receptor and the thyroid hormone receptor was stimulated by Hic-5 in the presence but not in the absence of coexpressed coactivator GRIP1. In biochemical fractionations and indirect immunofluorescence assays, a fraction of endogenous Hic-5 in REF-52 cells and transiently expressed Hic-5 in Cos-1 cells was associated with the nuclear matrix. The C-terminal region of Hic-5, which contains seven zinc fingers arranged in four LIM domains, was required for interaction with focal adhesions, the nuclear matrix, steroid receptors, and the tau2 domain of glucocorticoid receptor. The N-terminal region of Hic-5 possesses a transcriptional activation domain and was essential for the coactivator activity of Hic-5. Given the coexisting cytoplasmic and nuclear distributions of Hic-5 and its role in steroid receptor-mediated transcriptional activation, it is proposed that Hic-5 might transmit signals that emanate at cell attachment sites and regulate transcription factors, such as steroid receptors.
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337
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Smith TG, Kim B, Hong H, Desser SS. Intraerythrocytic development of species of Hepatozoon infecting ranid frogs: evidence for convergence of life cycle characteristics among apicomplexans. J Parasitol 2000; 86:451-8. [PMID: 10864239 DOI: 10.1645/0022-3395(2000)086[0451:idosoh]2.0.co;2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Intraerythrocytic development of the adeleorin apicomplexans Hepatozoon clamatae and Hepatozoon catesbianae were investigated in the bullfrog, Rana catesbeiana, the green frog, Rana clamitans melanota, and the Northern leopard frog, Rana pipiens. Merozoites emerging from hepatic meronts penetrated erythrocytes and underwent 1-3 rounds of binary fission to produce 2-8 merozoites. Following their release from infected erythrocytes, individual merozoites entered new cells and transformed into gamonts. Although this is the first report of intraerythrocytic development for a fully described species of Hepatozoon, a phylogenetic reanalysis of 11 species of Hepatozoon, 6 species representative of the 5 other hemogregarine taxa, 2 species of dactylosomatids, and 2 species of piroplasms, indicates that asexual reproduction of parasites within blood cells of vertebrates has arisen at least 3 times in the apicomplexan lineage that includes adeleorins and piroplasms. This method of asexual development, which is also observed in species of hemospororin genera such as Plasmodium, is discussed in the context of the evolution of apicomplexan life cycles. In addition to supporting the paraphyly of the genus Hepatozoon determined in an earlier study, this phylogenetic analysis featured a monophyletic group, consisting of the sister taxa Hemolivia and Karyolysus, that was the sister group to a clade consisting of the more derived hemogregarines, the dactylosomatids, and the piroplasms.
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338
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Lee J, Hong H, Im J, Byun H, Kim D. The formation of PHF-1 and SMI-31 positive dystrophic neurites in rat hippocampus following acute injection of okadaic acid. Neurosci Lett 2000; 282:49-52. [PMID: 10713393 DOI: 10.1016/s0304-3940(00)00863-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Within neurofibrillary tangles and dystrophic neurites of Alzheimer's disease (AD), tau protein is hyperphosphorylated. In the present study, we provide evidence that acute injection of okadaic acid (1 mM, 0.5 microliter) into the dorsal hippocampus induces the formation of paired helical filament (PHF)-1, sternberger monoclonals incorporated (SMI)-31, and amyloid precursor protein (APP) positive dystrophic neurites in the lacunosum-molecular layer of CA1 and molecular layer of dentate gyrus. Okadaic acid evoked a marked loss of microtubule associated protein (MAP)-2 immunoreactivity. PHF-1 immunoreactive terminals were fine, and SMI-31 immunoreactive terminals appeared at granular terminals and at the ring-like or elongated dystrophic neurites. APP positive dystrophic neurites exhibited large bulb-like globular terminals. Interestingly, APP dystrophic neurites were co-localized with SMI-31 immunoreactivity in the core. APP immunoreactivity became stronger over 24 h even in vehicle injected area. These results may provide the morphological evidence for the animal model to study dystrophic neurites formation of AD.
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339
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Behr J, Choi SM, Grosskopf S, Hong H, Nam SA, Hildebrand A, Kim MH, Sakas G. [3D models for diagnosis and treatment planning in cardiology]. Radiologe 2000; 40:256-61. [PMID: 10789124 DOI: 10.1007/s001170050666] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Due to the development new of imaging devices which produce a large number of tomographic slices, advanced techniques for the evaluation of the large amount of data are required. Computer supported extraction of dynamic 3D-models of the patients anatomy from temporal series thus is highly desirable. Since the diagnostician should be able to quickly make sensible decisions based on the models, high accuracy is required within a minimum of time. We present modeling and visualization techniques that are realized within the Cardiac Station. Results for the application of these techniques to cardiac image data demonstrate their usability. Besides giving information about the patients morphology functional parameters can be derived from the data and visualized together with the model. In order to verify the model with the original image data and for the planning of real intervention interaction techniques are presented.
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340
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Choi MY, Kim HJ, Kim D, Hong H. Synchronization in a system of globally coupled oscillators with time delay. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 2000; 61:371-81. [PMID: 11046275 DOI: 10.1103/physreve.61.371] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/1999] [Revised: 09/27/1999] [Indexed: 11/07/2022]
Abstract
We study the synchronization phenomena in a system of globally coupled oscillators with time delay in the coupling. The self-consistency equations for the order parameter are derived, which depend explicitly on the amount of delay. Analysis of these equations reveals that the system in general exhibits discontinuous transitions in addition to the usual continuous transition, between the incoherent state and a multitude of coherent states with different synchronization frequencies. In particular, the phase diagram is obtained on the plane of the coupling strength and the delay time, and ubiquity of multistability as well as suppression of the synchronization frequency is manifested. Numerical simulations are also performed to give consistent results.
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341
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Xie W, Hong H, Yang NN, Lin RJ, Simon CM, Stallcup MR, Evans RM. Constitutive activation of transcription and binding of coactivator by estrogen-related receptors 1 and 2. Mol Endocrinol 1999; 13:2151-62. [PMID: 10598588 DOI: 10.1210/mend.13.12.0381] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
In this report, we demonstrate that, in contrast to most previously characterized nuclear receptors, hERR1 and hERR2 (human estrogen receptor-related protein 1 and -2) are constitutive activators of the classic estrogen response element (ERE) as well as the palindromic thyroid hormone response element (TRE(pal)) but not the glucocorticoid response element (GRE). This intrinsically activated state of hERR1 and hERR2 resides in the ligand-binding domains of the two genes and is transferable to a heterologous receptor. In addition, we show that members of the p160 family of nuclear receptor coactivators, ACTR (activator of thyroid and retinoic acid receptors), GRIP1 (glucocorticoid receptor interacting protein 1), and SRC-1 (steroid receptor coactivator 1), potentiate the transcriptional activity by hERR1 and hERR2 in mammalian cells, and that both orphan receptors bind the coactivators in a ligand-independent manner. Together, these results suggest that hERR1 and hERR2 activate gene transcription through a mechanism different from most of the previously characterized steroid hormone receptors.
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342
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Hong H, Choi MY, Park K, Yoon BG, Soh KS. Synchronization and resonance in a driven system of coupled oscillators. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1999; 60:4014-20. [PMID: 11970238 DOI: 10.1103/physreve.60.4014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/1999] [Indexed: 04/18/2023]
Abstract
We study the noise effects in a driven system of globally coupled oscillators, with particular attention to the interplay between driving and noise. The self-consistency equation for the order parameter, which measures the collective synchronization of the system, is derived; it is found that the total order parameter decreases monotonically with noise, indicating overall suppression of synchronization. Still, for large coupling strengths, there exists an optimal noise level at which the periodic (ac) component of the order parameter reaches its maximum. The response of the phase velocity is also examined and found to display resonance behavior.
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343
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Ma H, Hong H, Huang SM, Irvine RA, Webb P, Kushner PJ, Coetzee GA, Stallcup MR. Multiple signal input and output domains of the 160-kilodalton nuclear receptor coactivator proteins. Mol Cell Biol 1999; 19:6164-73. [PMID: 10454563 PMCID: PMC84548 DOI: 10.1128/mcb.19.9.6164] [Citation(s) in RCA: 168] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/1999] [Accepted: 06/08/1999] [Indexed: 11/20/2022] Open
Abstract
Members of the 160-kDa nuclear receptor coactivator family (p160 coactivators) bind to the conserved AF-2 activation function found in the hormone binding domains of nuclear receptors (NR) and are potent transcriptional coactivators for NRs. Here we report that the C-terminal region of p160 coactivators glucocorticoid receptor interacting protein 1 (GRIP1), steroid receptor coactivator 1 (SRC-1a), and SRC-1e binds the N-terminal AF-1 activation function of the androgen receptor (AR), and p160 coactivators can thereby enhance transcriptional activation by AR. While they all interact efficiently with AR AF-1, these same coactivators have vastly different binding strengths with and coactivator effects on AR AF-2. p160 activation domain AD1, which binds secondary coactivators CREB binding protein (CBP) and p300, was previously implicated as the principal domain for transmitting the activating signal to the transcription machinery. We identified a new highly conserved motif in the AD1 region which is important for CBP/p300 binding. Deletion of AD1 only partially reduced p160 coactivator function, due to signaling through AD2, another activation domain located at the C-terminal end of p160 coactivators. C-terminal coactivator fragments lacking AD1 but containing AD2 and the AR AF-1 binding site served as efficient coactivators for full-length AR and AR AF-1. The two signal input domains (one that binds NR AF-2 domains and one that binds AF-1 domains of some but not all NRs) and the two signal output domains (AD1 and AD2) of p160 coactivators played different relative roles for two different NRs: AR and thyroid hormone receptor.
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344
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Hong H, Yang L, Stallcup MR. Hormone-independent transcriptional activation and coactivator binding by novel orphan nuclear receptor ERR3. J Biol Chem 1999; 274:22618-26. [PMID: 10428842 DOI: 10.1074/jbc.274.32.22618] [Citation(s) in RCA: 223] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Orphan nuclear receptors share sequence homology with members of the nuclear receptor superfamily, but ligands are unknown or unnecessary. A novel orphan receptor, estrogen receptor-related protein 3 (ERR3), was identified by yeast two-hybrid screening, using the transcriptional coactivator glucocorticoid receptor interacting protein 1 (GRIP1) as bait. The putative full-length mouse ERR3 contains 458 amino acids and is closely related to two known orphan receptors ERR1 and ERR2. All the ERR family members share an almost identical DNA-binding domain, which has 68% amino acid identity with that of estrogen receptor. ERR3 bound specifically to an estrogen response element and activated reporter genes controlled by estrogen response elements, both in yeast and in mammalian cells, in the absence of any added ligand. A conserved AF-2 activation domain located in the hormone-binding domain of ERR3 was primarily responsible for transcriptional activation. The ERR3 AF-2 domain bound GRIP1 in a ligand-independent manner both in vitro and in vivo, through the LXXLL motifs of GRIP1, and GRIP1 functioned as a transcriptional coactivator for ERR3 in both yeast and mammalian cells. Expression of ERR3 in adult mouse was restricted; highest expression was observed in heart, kidney, and brain. In the mouse embryo no expression was observed at day 7, and highest expression occurred around the 11-15 day stages. Although ERR3 is much more closely related to ERR2 than to ERR1, the expression pattern for ERR3 was similar to that of ERR1 and distinct from that for ERR2, suggesting a unique role for ERR3 in development.
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345
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Hong H, Sheffer DB, Loughry CW. Detection of breast lesions by holographic interferometry. JOURNAL OF BIOMEDICAL OPTICS 1999; 4:368-375. [PMID: 23015258 DOI: 10.1117/1.429938] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The holographic interferometry (HI) technique commonly used for nondestructive testing of laminate materials was applied to create fringe contour distortion near the site of indwelling breast lesions. For this medical imaging application, the HI technique was successful in demonstrating abnormal mechanical properties of living tissue. Adequate density and contrast of fringes, crucial factors necessary for analysis of surface deformation of an object, can be made only with an appropriate stressing method. We have applied vibration and mild pressure to the surface of female breasts for the purpose of detecting localized densities and mass alterations of the tissue, which may be indicative of an abnormality of that tissue. Even though each stressing method had both positive and negative aspects, pneumatic pressure was adopted for the present study because it was more suitable for a noninvasive and noncontact breast examination. We also developed a computer based holographic imaging system to precisely control the stressing phase for the pressure and laser triggering so the resultant holograms had manageable fringe density and repeatability. © 1999 Society of Photo-Optical Instrumentation Engineers.
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346
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Chen D, Ma H, Hong H, Koh SS, Huang SM, Schurter BT, Aswad DW, Stallcup MR. Regulation of transcription by a protein methyltransferase. Science 1999; 284:2174-7. [PMID: 10381882 DOI: 10.1126/science.284.5423.2174] [Citation(s) in RCA: 893] [Impact Index Per Article: 35.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The p160 family of coactivators, SRC-1, GRIP1/TIF2, and p/CIP, mediate transcriptional activation by nuclear hormone receptors. Coactivator-associated arginine methyltransferase 1 (CARM1), a previously unidentified protein that binds to the carboxyl-terminal region of p160 coactivators, enhanced transcriptional activation by nuclear receptors, but only when GRIP1 or SRC-1a was coexpressed. Thus, CARM1 functions as a secondary coactivator through its association with p160 coactivators. CARM1 can methylate histone H3 in vitro, and a mutation in the putative S-adenosylmethionine binding domain of CARM1 substantially reduced both methyltransferase and coactivator activities. Thus, coactivator-mediated methylation of proteins in the transcription machinery may contribute to transcriptional regulation.
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347
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Jenkins EC, Wen GY, Kim KS, Zhong N, Sapienza VJ, Hong H, Chen J, Li SY, Houck GE, Ding X, Nolin SL, Dobkin CS, Brown WT. Prenatal fragile X detection using cytoplasmic and nuclear-specific monoclonal antibodies. AMERICAN JOURNAL OF MEDICAL GENETICS 1999; 83:342-6. [PMID: 10208177 DOI: 10.1002/(sici)1096-8628(19990402)83:4<342::aid-ajmg24>3.0.co;2-h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We have been carrying out studies aimed at improving prenatal detection of the fragile X chromosome/mutation. Our current protocol requires a turnaround time (TAT) of several days. In an attempt to reduce the TAT, we have turned to the use of monoclonal antibodies (mAbs). Monoclonal antibody 1A1 (provided by Dr. Mandel of INSERM) immunostaining was performed according to a modified three-step immunocytochemical procedure. We found that cytoplasmic staining intensities, using mAb 1A1/avidin biotinylated complex/diaminobenzidine, varied from light to heavy within each sample, with controls exhibiting a majority of heavily stained cells in both chorionic villus (CV) sample and amniotic fluid cultured cells. Using mAb 1A1 and a new nuclear-specific antibody, mAb 3F11, we found that CV cultured cells harboring the FMR1 full mutation could be distinguished from controls as early as 10 weeks of gestation in both male and female specimens. Western blot analysis showed that the antibodies have similar staining patterns but that mAb 3F11 has fewer background/nonspecific bands. Our results demonstrate that it is feasible to detect fragile X full mutations within one day after obtaining cells from CV specimens taken as early as 10 weeks of gestation.
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348
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Hong H, Darimont BD, Ma H, Yang L, Yamamoto KR, Stallcup MR. An additional region of coactivator GRIP1 required for interaction with the hormone-binding domains of a subset of nuclear receptors. J Biol Chem 1999; 274:3496-502. [PMID: 9920895 DOI: 10.1074/jbc.274.6.3496] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Transcriptional coactivators of the p160 family (SRC-1, GRIP1, and p/CIP) associate with DNA-bound nuclear receptors (NRs) and help the NRs to recruit an active transcription initiation complex to the promoters of target genes. Previous studies have demonstrated the importance of the NR interaction domain (NID) of p160 proteins containing three NR box motifs (LXXLL) for the interaction with the hormone-binding domains of NRs. Here we report that, in addition to NID, another region of coactivator GRIP1 (amino acids 1011-1121), called the auxiliary NID (NIDaux), is required in vitro and in vivo for efficient interaction with a subset of NRs, including the glucocorticoid receptor (GR), androgen receptor, and retinoic acid receptor alpha. A second group of NRs, which includes the progesterone receptor, retinoid X receptor alpha, thyroid hormone receptor beta1, and vitamin D receptor, required only NID for efficient interaction. For binding to GR, the NID and NIDaux of GRIP1 must act in cis, but deletion of up to 144 amino acids between the two regions did not reduce binding efficiency. Amino acids 1011-1121 of GRIP1 also contain a p300 interaction domain, but mutational analysis indicated that the p300 interaction function within this region is separable from the ability to contribute to GR hormone-binding domain binding. SRC-1 lacks an NIDaux activity equivalent to that in GRIP1.
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349
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Kim YR, Hahn JS, Hong H, Jeong W, Song NW, Shin HC, Kim D. Dynamic equilibrium unfolding pathway of human tumor necrosis factor-alpha induced by guanidine hydrochloride. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1429:486-95. [PMID: 9989234 DOI: 10.1016/s0167-4838(98)00263-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The dynamic equilibrium unfolding pathway of human tumor necrosis factor-alpha (TNF-alpha) during denaturation at different guanidine hydrochloride (GdnHCl) concentrations (0-4.2 M) was investigated by steady-state fluorescence spectroscopy, potassium iodide (KI) fluorescence quenching, far-UV circular dichroism (CD), picosecond time-resolved fluorescence lifetime, and anisotropy decay measurements. We utilized the intrinsic fluorescence of Trp-28 and Trp-114 to characterize the conformational changes involved in the equilibrium unfolding pathway. The detailed unfolding pathway under equilibrium conditions was discussed with respect to motional dynamics and partially folded structures. At 0-0.9 M [GdnHCl], the rotational correlation times of 22-25 ns were obtained from fluorescence anisotropy decay measurements and assigned to those of trimeric states by hydrodynamic calculation. In this range, the solvent accessibility of Trp residues increased with increasing [GdnHCl], suggesting the slight expansion of the trimeric structure. At 1.2-2.1 M [GdnHCl], the enhanced solvent accessibility and the rotational degree of freedom of Trp residues were observed, implying the loosening of the internal structure. In this [GdnHCl] region, TNF-alpha was thought to be in soluble aggregates having distinct conformational characteristics from a native (N) or fully unfolded state (U). At 4.2 M [GdnHCl], TNF-alpha unfolded to a U-state. From these results, the equilibrium unfolding pathway of TNF-alpha, trimeric and all beta-sheet protein, could not be viewed from the simple two state model (N-->U).
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350
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Hong H, Choi MY, Yoon BG, Park K, Soh KS. Noise effects on synchronization in systems of coupled oscillators. ACTA ACUST UNITED AC 1999. [DOI: 10.1088/0305-4470/32/1/002] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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