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Aprile E, Aalbers J, Agostini F, Alfonsi M, Anthony M, Arazi L, Arisaka K, Arneodo F, Balan C, Barrow P, Baudis L, Bauermeister B, Breur PA, Brown A, Brown E, Bruenner S, Bruno G, Budnik R, Bütikofer L, Cardoso JMR, Cervantes M, Coderre D, Colijn AP, Contreras H, Cussonneau JP, Decowski MP, de Perio P, Di Giovanni A, Duchovni E, Fattori S, Ferella AD, Fieguth A, Fulgione W, Gao F, Garbini M, Geis C, Goetzke LW, Grignon C, Gross E, Hampel W, Hasterok C, Itay R, Kaether F, Kaminsky B, Kessler G, Kish A, Landsman H, Lang RF, Le Calloch M, Lellouch D, Levinson L, Levy C, Lindemann S, Lindner M, Lopes JAM, Lyashenko A, Macmullin S, Marrodán Undagoitia T, Masbou J, Massoli FV, Mayani D, Melgarejo Fernandez AJ, Meng Y, Messina M, Micheneau K, Miguez B, Molinario A, Murra M, Naganoma J, Ni K, Oberlack U, Orrigo SEA, Pakarha P, Persiani R, Piastra F, Pienaar J, Plante G, Priel N, Rauch L, Reichard S, Reuter C, Rizzo A, Rosendahl S, Dos Santos JMF, Sartorelli G, Schindler S, Schreiner J, Schumann M, Scotto Lavina L, Selvi M, Shagin P, Simgen H, Teymourian A, Thers D, Tiseni A, Trinchero G, Tunnell C, Wall R, Wang H, Weber M, Weinheimer C, Zhang Y. Search for Event Rate Modulation in XENON100 Electronic Recoil Data. PHYSICAL REVIEW LETTERS 2015; 115:091302. [PMID: 26371638 DOI: 10.1103/physrevlett.115.091302] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Indexed: 06/05/2023]
Abstract
We have searched for periodic variations of the electronic recoil event rate in the (2-6) keV energy range recorded between February 2011 and March 2012 with the XENON100 detector, adding up to 224.6 live days in total. Following a detailed study to establish the stability of the detector and its background contributions during this run, we performed an unbinned profile likelihood analysis to identify any periodicity up to 500 days. We find a global significance of less than 1σ for all periods, suggesting no statistically significant modulation in the data. While the local significance for an annual modulation is 2.8σ, the analysis of a multiple-scatter control sample and the phase of the modulation disfavor a dark matter interpretation. The DAMA/LIBRA annual modulation interpreted as a dark matter signature with axial-vector coupling of weakly interacting massive particles to electrons is excluded at 4.8σ.
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Gong H, Wang DN, Xu B, Ni K, Liu H, Zhao CL. Miniature and robust optical fiber in-line Mach-Zehnder interferometer based on a hollow ellipsoid. OPTICS LETTERS 2015; 40:3516-3519. [PMID: 26258346 DOI: 10.1364/ol.40.003516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
An optical fiber in-line Mach-Zehnder interferometer based on a hollow ellipsoid fabricated by femtosecond laser micromachining and fusion-splicing technique is demonstrated. The surface of the hollow ellipsoid acts as an internal mirror that can be utilized for the construction of an interferometer. Such an interferometer device is miniature and robust and can perform external refractive index, curvature, and high-temperature sensing in a mutually independent way, and hence a simultaneous multiple parameter measurement capability can be readily achieved.
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Aprile E, Alfonsi M, Arisaka K, Arneodo F, Balan C, Baudis L, Bauermeister B, Behrens A, Beltrame P, Bokeloh K, Brown A, Brown E, Bruno G, Budnik R, Cardoso JMR, Chen WT, Choi B, Colijn AP, Contreras H, Cussonneau JP, Decowski MP, Duchovni E, Fattori S, Ferella AD, Fulgione W, Gao F, Garbini M, Ghag C, Giboni KL, Goetzke LW, Grignon C, Gross E, Hampel W, Kaether F, Kish A, Lamblin J, Landsman H, Lang RF, Le Calloch M, Lellouch D, Levy C, Lim KE, Lin Q, Lindemann S, Lindner M, Lopes JAM, Lung K, Marrodán Undagoitia T, Massoli FV, Melgarejo Fernandez AJ, Meng Y, Messina M, Molinario A, Ni K, Oberlack U, Orrigo SEA, Pantic E, Persiani R, Plante G, Priel N, Rizzo A, Rosendahl S, dos Santos JMF, Sartorelli G, Schreiner J, Schumann M, Scotto Lavina L, Scovell PR, Selvi M, Shagin P, Simgen H, Teymourian A, Thers D, Vitells O, Wang H, Weber M, Weinheimer C. Limits on spin-dependent WIMP-nucleon cross sections from 225 live days of XENON100 data. PHYSICAL REVIEW LETTERS 2013; 111:021301. [PMID: 23889382 DOI: 10.1103/physrevlett.111.021301] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Revised: 05/05/2013] [Indexed: 06/02/2023]
Abstract
We present new experimental constraints on the elastic, spin-dependent WIMP-nucleon cross section using recent data from the XENON100 experiment, operated in the Laboratori Nazionali del Gran Sasso in Italy. An analysis of 224.6 live days×34 kg of exposure acquired during 2011 and 2012 revealed no excess signal due to axial-vector WIMP interactions with 129Xe and 131Xe nuclei. This leads to the most stringent upper limits on WIMP-neutron cross sections for WIMP masses above 6 GeV/c², with a minimum cross section of 3.5×10(-40) cm² at a WIMP mass of 45 GeV/c², at 90% confidence level.
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Kondo MA, Tajinda K, Colantuoni C, Hiyama H, Seshadri S, Huang B, Pou S, Furukori K, Hookway C, Jaaro-Peled H, Kano SI, Matsuoka N, Harada K, Ni K, Pevsner J, Sawa A. Unique pharmacological actions of atypical neuroleptic quetiapine: possible role in cell cycle/fate control. Transl Psychiatry 2013; 3:e243. [PMID: 23549417 PMCID: PMC3641406 DOI: 10.1038/tp.2013.19] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Quetiapine is an atypical neuroleptic with a pharmacological profile distinct from classic neuroleptics that function primarily via blockade of dopamine D2 receptors. In the United States, quetiapine is currently approved for treating patients with schizophrenia, major depression and bipolar I disorder. Despite its widespread use, its cellular effects remain elusive. To address possible mechanisms, we chronically treated mice with quetiapine, haloperidol or vehicle and examined quetiapine-specific gene expression change in the frontal cortex. Through microarray analysis, we observed that several groups of genes were differentially expressed upon exposure to quetiapine compared with haloperidol or vehicle; among them, Cdkn1a, the gene encoding p21, exhibited the greatest fold change relative to haloperidol. The quetiapine-induced downregulation of p21/Cdkn1a was confirmed by real-time polymerase chain reaction and in situ hybridization. Consistent with single gene-level analyses, functional group analyses also indicated that gene sets associated with cell cycle/fate were differentially regulated in the quetiapine-treated group. In cortical cell cultures treated with quetiapine, p21/Cdkn1a was significantly downregulated in oligodendrocyte precursor cells and neurons, but not in astrocytes. We propose that cell cycle-associated intervention by quetiapine in the frontal cortex may underlie a unique efficacy of quetiapine compared with typical neuroleptics.
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Aprile E, Alfonsi M, Arisaka K, Arneodo F, Balan C, Baudis L, Bauermeister B, Behrens A, Beltrame P, Bokeloh K, Brown E, Bruno G, Budnik R, Cardoso JMR, Chen WT, Choi B, Cline D, Colijn AP, Contreras H, Cussonneau JP, Decowski MP, Duchovni E, Fattori S, Ferella AD, Fulgione W, Gao F, Garbini M, Ghag C, Giboni KL, Goetzke LW, Grignon C, Gross E, Hampel W, Kaether F, Kish A, Lamblin J, Landsman H, Lang RF, Le Calloch M, Levy C, Lim KE, Lin Q, Lindemann S, Lindner M, Lopes JAM, Lung K, Marrodán Undagoitia T, Massoli FV, Melgarejo Fernandez AJ, Meng Y, Molinario A, Nativ E, Ni K, Oberlack U, Orrigo SEA, Pantic E, Persiani R, Plante G, Priel N, Rizzo A, Rosendahl S, dos Santos JMF, Sartorelli G, Schreiner J, Schumann M, Scotto Lavina L, Scovell PR, Selvi M, Shagin P, Simgen H, Teymourian A, Thers D, Vitells O, Wang H, Weber M, Weinheimer C. Dark matter results from 225 live days of XENON100 data. PHYSICAL REVIEW LETTERS 2012; 109:181301. [PMID: 23215267 DOI: 10.1103/physrevlett.109.181301] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Indexed: 06/01/2023]
Abstract
We report on a search for particle dark matter with the XENON100 experiment, operated at the Laboratori Nazionali del Gran Sasso for 13 months during 2011 and 2012. XENON100 features an ultralow electromagnetic background of (5.3 ± 0.6) × 10(-3) events/(keV(ee) × kg × day) in the energy region of interest. A blind analysis of 224.6 live days × 34 kg exposure has yielded no evidence for dark matter interactions. The two candidate events observed in the predefined nuclear recoil energy range of 6.6-30.5 keV(nr) are consistent with the background expectation of (1.0 ± 0.2) events. A profile likelihood analysis using a 6.6-43.3 keV(nr) energy range sets the most stringent limit on the spin-independent elastic weakly interacting massive particle-nucleon scattering cross section for weakly interacting massive particle masses above 8 GeV/c(2), with a minimum of 2 × 10(-45) cm(2) at 55 GeV/c(2) and 90% confidence level.
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Aprile E, Arisaka K, Arneodo F, Askin A, Baudis L, Behrens A, Bokeloh K, Brown E, Cardoso JMR, Choi B, Cline D, Fattori S, Ferella AD, Giboni KL, Kish A, Lam CW, Lamblin J, Lang RF, Lim KE, Lin Q, Lindemann S, Lindner M, Lopes JAM, Lung K, Marrodán Undagoitia T, Mei Y, Melgarejo Fernandez AJ, Ni K, Oberlack U, Orrigo SEA, Pantic E, Plante G, Ribeiro ACC, Santorelli R, dos Santos JMF, Schumann M, Shagin P, Simgen H, Teymourian A, Thers D, Tziaferi E, Wang H, Weber M, Weinheimer C. Erratum: Study of the electromagnetic background in the XENON100 experiment [Phys. Rev. D 83, 082001 (2011)]. Int J Clin Exp Med 2012. [DOI: 10.1103/physrevd.85.029904] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Aprile E, Arisaka K, Arneodo F, Askin A, Baudis L, Behrens A, Bokeloh K, Brown E, Bruch T, Bruno G, Cardoso JMR, Chen WT, Choi B, Cline D, Duchovni E, Fattori S, Ferella AD, Gao F, Giboni KL, Gross E, Kish A, Lam CW, Lamblin J, Lang RF, Levy C, Lim KE, Lin Q, Lindemann S, Lindner M, Lopes JAM, Lung K, Undagoitia TM, Mei Y, Fernandez AJM, Ni K, Oberlack U, Orrigo SEA, Pantic E, Persiani R, Plante G, Ribeiro ACC, Santorelli R, dos Santos JMF, Sartorelli G, Schumann M, Selvi M, Shagin P, Simgen H, Teymourian A, Thers D, Vitells O, Wang H, Weber M, Weinheimer C. Dark matter results from 100 live days of XENON100 data. PHYSICAL REVIEW LETTERS 2011; 107:131302. [PMID: 22026838 DOI: 10.1103/physrevlett.107.131302] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 07/18/2011] [Indexed: 05/31/2023]
Abstract
We present results from the direct search for dark matter with the XENON100 detector, installed underground at the Laboratori Nazionali del Gran Sasso of INFN, Italy. XENON100 is a two-phase time-projection chamber with a 62 kg liquid xenon target. Interaction vertex reconstruction in three dimensions with millimeter precision allows the selection of only the innermost 48 kg as the ultralow background fiducial target. In 100.9 live days of data, acquired between January and June 2010, no evidence for dark matter is found. Three candidate events were observed in the signal region with an expected background of (1.8 ± 0.6) events. This leads to the most stringent limit on dark matter interactions today, excluding spin-independent elastic weakly interacting massive particle (WIMP) nucleon scattering cross sections above 7.0 × 10(-45) cm(2) for a WIMP mass of 50 GeV/c(2) at 90% confidence level.
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Angle J, Aprile E, Arneodo F, Baudis L, Bernstein A, Bolozdynya AI, Coelho LCC, Dahl CE, DeViveiros L, Ferella AD, Fernandes LMP, Fiorucci S, Gaitskell RJ, Giboni KL, Gomez R, Hasty R, Kastens L, Kwong J, Lopes JAM, Madden N, Manalaysay A, Manzur A, McKinsey DN, Monzani ME, Ni K, Oberlack U, Orboeck J, Plante G, Santorelli R, dos Santos JMF, Schulte S, Shagin P, Shutt T, Sorensen P, Winant C, Yamashita M. Search for light dark matter in XENON10 data. PHYSICAL REVIEW LETTERS 2011; 107:051301. [PMID: 21867059 DOI: 10.1103/physrevlett.107.051301] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 06/03/2011] [Indexed: 05/31/2023]
Abstract
We report results of a search for light (≲10 GeV) particle dark matter with the XENON10 detector. The event trigger was sensitive to a single electron, with the analysis threshold of 5 electrons corresponding to 1.4 keV nuclear recoil energy. Considering spin-independent dark matter-nucleon scattering, we exclude cross sections σ(n)>7×10(-42) cm(2), for a dark matter particle mass m(χ)=7 GeV. We find that our data strongly constrain recent elastic dark matter interpretations of excess low-energy events observed by CoGeNT and CRESST-II, as well as the DAMA annual modulation signal.
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Aprile E, Arisaka K, Arneodo F, Askin A, Baudis L, Behrens A, Bokeloh K, Brown E, Cardoso JMR, Choi B, Cline DB, Fattori S, Ferella AD, Giboni KL, Kish A, Lam CW, Lamblin J, Lang RF, Lim KE, Lopes JAM, Marrodán Undagoitia T, Mei Y, Melgarejo Fernandez AJ, Ni K, Oberlack U, Orrigo SEA, Pantic E, Plante G, Ribeiro ACC, Santorelli R, Dos Santos JMF, Schumann M, Shagin P, Teymourian A, Thers D, Tziaferi E, Wang H, Weinheimer C. First dark matter results from the XENON100 experiment. PHYSICAL REVIEW LETTERS 2010; 105:131302. [PMID: 21230760 DOI: 10.1103/physrevlett.105.131302] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Revised: 06/07/2010] [Indexed: 05/30/2023]
Abstract
The XENON100 experiment, in operation at the Laboratori Nazionali del Gran Sasso in Italy, is designed to search for dark matter weakly interacting massive particles (WIMPs) scattering off 62 kg of liquid xenon in an ultralow background dual-phase time projection chamber. In this Letter, we present first dark matter results from the analysis of 11.17 live days of nonblind data, acquired in October and November 2009. In the selected fiducial target of 40 kg, and within the predefined signal region, we observe no events and hence exclude spin-independent WIMP-nucleon elastic scattering cross sections above 3.4 × 10⁻⁴⁴ cm² for 55 GeV/c² WIMPs at 90% confidence level. Below 20 GeV/c², this result constrains the interpretation of the CoGeNT and DAMA signals as being due to spin-independent, elastic, light mass WIMP interactions.
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Shobo M, Kondo Y, Yamada H, Mihara T, Yamamoto N, Katsuoka M, Harada K, Ni K, Matsuoka N. Norzotepine, a Major Metabolite of Zotepine, Exerts Atypical Antipsychotic-Like and Antidepressant-Like Actions through Its Potent Inhibition of Norepinephrine Reuptake. J Pharmacol Exp Ther 2010; 333:772-81. [DOI: 10.1124/jpet.110.166264] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Ni K, Bourgeat-Lami E, Sheibat-Othman N, Shan G, Fevotte G. Preparation of Hybrid Nanocapsules. ACTA ACUST UNITED AC 2008. [DOI: 10.1002/masy.200851113] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Angle J, Aprile E, Arneodo F, Baudis L, Bernstein A, Bolozdynya A, Coelho LCC, Dahl CE, DeViveiros L, Ferella AD, Fernandes LMP, Fiorucci S, Gaitskell RJ, Giboni KL, Gomez R, Hasty R, Kastens L, Kwong J, Lopes JAM, Madden N, Manalaysay A, Manzur A, McKinsey DN, Monzani ME, Ni K, Oberlack U, Orboeck J, Plante G, Santorelli R, dos Santos JMF, Shagin P, Shutt T, Sorensen P, Schulte S, Winant C, Yamashita M. Limits on spin-dependent WIMP-nucleon cross sections from the XENON10 experiment. PHYSICAL REVIEW LETTERS 2008; 101:091301. [PMID: 18851599 DOI: 10.1103/physrevlett.101.091301] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2008] [Revised: 07/11/2008] [Indexed: 05/26/2023]
Abstract
XENON10 is an experiment to directly detect weakly interacting massive particles (WIMPs), which may comprise the bulk of the nonbaryonic dark matter in our Universe. We report new results for spin-dependent WIMP-nucleon interactions with 129Xe and 131Xe from 58.6 live days of operation at the Laboratori Nazionali del Gran Sasso. Based on the nonobservation of a WIMP signal in 5.4 kg of fiducial liquid xenon mass, we exclude previously unexplored regions in the theoretically allowed parameter space for neutralinos. We also exclude a heavy Majorana neutrino with a mass in the range of approximately 10 GeV/c2-2 TeV/c2 as a dark matter candidate under standard assumptions for its density and distribution in the galactic halo.
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Angle J, Aprile E, Arneodo F, Baudis L, Bernstein A, Bolozdynya A, Brusov P, Coelho LCC, Dahl CE, DeViveiros L, Ferella AD, Fernandes LMP, Fiorucci S, Gaitskell RJ, Giboni KL, Gomez R, Hasty R, Kastens L, Kwong J, Lopes JAM, Madden N, Manalaysay A, Manzur A, McKinsey DN, Monzani ME, Ni K, Oberlack U, Orboeck J, Plante G, Santorelli R, dos Santos JMF, Shagin P, Shutt T, Sorensen P, Schulte S, Winant C, Yamashita M. First results from the XENON10 dark matter experiment at the Gran Sasso National Laboratory. PHYSICAL REVIEW LETTERS 2008; 100:021303. [PMID: 18232850 DOI: 10.1103/physrevlett.100.021303] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Indexed: 05/25/2023]
Abstract
The XENON10 experiment at the Gran Sasso National Laboratory uses a 15 kg xenon dual phase time projection chamber to search for dark matter weakly interacting massive particles (WIMPs). The detector measures simultaneously the scintillation and the ionization produced by radiation in pure liquid xenon to discriminate signal from background down to 4.5 keV nuclear-recoil energy. A blind analysis of 58.6 live days of data, acquired between October 6, 2006, and February 14, 2007, and using a fiducial mass of 5.4 kg, excludes previously unexplored parameter space, setting a new 90% C.L. upper limit for the WIMP-nucleon spin-independent cross section of 8.8x10(-44) cm2 for a WIMP mass of 100 GeV/c2, and 4.5x10(-44) cm2 for a WIMP mass of 30 GeV/c2. This result further constrains predictions of supersymmetric models.
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Aprile E, Dahl CE, de Viveiros L, Gaitskell RJ, Giboni KL, Kwong J, Majewski P, Ni K, Shutt T, Yamashita M. Simultaneous measurement of ionization and scintillation from nuclear recoils in liquid xenon for a dark matter experiment. PHYSICAL REVIEW LETTERS 2006; 97:081302. [PMID: 17026288 DOI: 10.1103/physrevlett.97.081302] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2006] [Indexed: 05/12/2023]
Abstract
We report the first measurements of the absolute ionization yield of nuclear recoils in liquid xenon, as a function of energy and electric field. Independent experiments were carried out with two dual-phase time-projection chamber prototypes, developed for the XENON dark matter project. We find that the charge yield increases with decreasing recoil energy, and exhibits only a weak field dependence. These results are the first unambiguous demonstration of the capability of dual-phase xenon detectors to discriminate between electron and nuclear recoils down to 20 keV, a key requirement for a sensitive dark matter search.
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Zhong W, Yu JS, Huang W, Ni K, Liang Y. Spectroscopic studies of interaction of chlorobenzylidine with DNA. Biopolymers 2002; 62:315-23. [PMID: 11857270 DOI: 10.1002/bip.10001] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Electronic absorbance and fluorescence titrations are used to probe the interaction of chlorobenzylidine with DNA. The binding of chlorobenzylidine to DNA results in hypochromism, a small shift to a longer wavelength in the absorption spectra, and emission quenching in the fluorescence spectra. These spectral characteristics suggest that chlorobenzylidine binds to DNA by an intercalative mode. This conclusion is reinforced by fluorescence polarization measurements. Scatchard plots constructed from fluorescence titration data give a binding constant of 1.3 x 10(5) M(-1) and a binding site size of 10 base pairs. This indicates that chlorobenzylidine has a high affinity with DNA. The intercalative interaction is exothermic with a Van't Hoff enthalpy of -143 kJ/mol. This result is obtained from the temperature dependence of the binding constant. The interaction of chlorobenzylidine with DNA is affected by the pH value of the solution. The binding constant has its maximum at pH 3.0. Upon binding to DNA, the fluorescence from chlorobenzylidine is quenched efficiently by the DNA bases and the fluorescence intensity tends to be constant at high concentrations of DNA when the binding is saturated. The Stern-Volmer quenching constant obtained from the linear quenching plot is 1.6 x 10(4) M(-1) at 25 degrees C. The measurements of the fluorescence lifetime and the dependence of the quenching constant on the temperature indicate that the fluorescence quenching process is static. The fluorescence lifetime of chlorobenzylidine is 1.9 +/- 0.4 ns.
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Ni K, O'Neill HC. Development of dendritic cells from GM-CSF-/- mice in vitro : GM-CSF enhances production and survival of cells. DEVELOPMENTAL IMMUNOLOGY 2001; 8:133-46. [PMID: 11589309 PMCID: PMC2276066 DOI: 10.1155/2001/68024] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The production of dendritic cells (DC) from haemopoietic progenitors maintained in long term stroma-dependent cultures (LTC) of spleen or bone marrow (BM) occurs independently of added granulocyte/macrophage colony stimulating factor (GM-CSF). The possibility that cultures depend on endogenous GM-CSF produced in low levels was tested by attempting to generate LTC from spleen and BM of GM-CSF-/- mice. Multiple cultures from GM-CSF-/- and wild type mice were established and compared for cell production. GM-CSF-/- LTC developed more slowly, but by 16 weeks produced cells resembling DC in numbers comparable to wild type cultures. LTC maintained distinct populations of small and large cells, the latter resembling DC. Cells collected from GM-CSF-/- LTC were capable antigen presenting cells (APC) for T cell stimulation and morphologically resembled DC. Large cells expressed the CD11b, CD11c, CD86, 33D1 and Dec-205 markers of DC. Addition of GM-CSF to GM-CSF-/- LTC increased the proportion of large, mature DC present in culture. Stromal cells from GM-CSF-/- LTC could support the differentiation of DC from early progenitors maintained in LTC without addition of GM-CSF. However, GM-CSF is not a critical factor in the in vitro generation of DC from progenitors. It can, however, substitute for stromal cells in increasing the survival of mature DC.
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Ni K, O'Neill HC. Improved FACS analysis confirms generation of immature dendritic cells in long-term stromal-dependent spleen cultures. Immunol Cell Biol 2000; 78:196-204. [PMID: 10849107 DOI: 10.1046/j.1440-1711.2000.00897.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cells produced in spleen stroma-dependent long-term cultures (LTC) have now been clearly defined as dendritic cells (DC). Characterization of cells by antibody staining and FACS analysis has only been possible using a procedure to quench the high autofluorescence of DC produced in LTC (LTC-DC). The population of large cells produced by the established LTC-X1 culture are homogeneously positive for a number of cell-surface markers expressed by DC. These include CD11c, CD11b, Dec-205, Fc receptor and CD86. They also express markers detectable with the F4/80 and 33D1 antibodies. Cells produced in LTC do not uniformly express the MHC II marker, consistent with an immature DC phenotype. Most cells are weakly positive for MHC II with a small subset of highly positive cells. The quenching method involves staining cells with crystal violet dye, which is taken up within the cell. The importance of optimizimg fluorescent antibody staining assays for delineating DC subsets is indicated and the LTC system is established as a valuable and continuous source of DC precursors.
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Wilson HL, Ni K, O'Neill HC. Identification of progenitor cells in long-term spleen stromal cultures that produce immature dendritic cells. Proc Natl Acad Sci U S A 2000; 97:4784-9. [PMID: 10758164 PMCID: PMC18310 DOI: 10.1073/pnas.080278897] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dendritic cells (DC) are produced continuously by a unique, long-term culture (LTC) system in which hemopoiesis is supported by a splenic stromal cell layer in the absence of added growth factors. Flow cytometric analysis reveals the production of two distinct cell subsets. The more predominant large-cell subset resembles highly endocytic DC that are large, granular, and possess membrane extensions. They also express high levels of the DC markers CD11c, CD11b, DEC-205, and CD80 on their cell surface. They do not resemble mature DC because they express low levels of MHC type II and CD86 molecules, as well as c-kit and Fc receptor (FcR). These are known characteristics of immature DC. Small cells are smaller and less granular than large cells, with negative to low expression of CD11c, DEC-205, and CD86. A majority of small cells express varying levels of CD11b and CD80. Subpopulations of small cells express low levels of c-kit, FcR, and MHC type II, and only a 20% subpopulation is weakly endocytic. Upon transfer to an irradiated stromal layer, cells within the small subset proliferate and differentiate to resemble the large cells in size, complexity, membrane extensions, and CD11c and CD86 expression. The two cell subsets produced in LTC are developmentally linked, with the heterogeneous small-cell subset containing progenitors of the larger homogeneous, immature DC subset. LTC represent a valuable model system for studying DC development from hemopoietic progenitors.
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Newman CS, Reecy J, Grow MW, Ni K, Boettger T, Kessel M, Schwartz RJ, Krieg PA. Transient cardiac expression of the tinman-family homeobox gene, XNkx2-10. Mech Dev 2000; 91:369-73. [PMID: 10704867 DOI: 10.1016/s0925-4773(99)00291-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
In Drosophila, the tinman homeobox gene is absolutely required for heart development. In the vertebrates, a small family of tinman-related genes, the cardiac NK-2 genes, appear to play a similar role in the formation of the vertebrate heart. However, targeted gene ablation of one of these genes, Nkx2-5, results in defects in only the late stages of cardiac development suggesting the presence of a rescuing gene function early in development. Here, we report the characterization of a novel tinman-related gene, XNkx2-10, which is expressed during early heart development in Xenopus. Using in vitro assays, we show that XNkx2-10 is capable of transactivating expression from promoters previously shown to be activated by other tinman-related genes, including Nkx2-5. Furthermore, Xenopus Nkx2-10 can synergize with the GATA-4 and SRF transcription factors to activate reporter gene expression.
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Wilson HL, Ni K, O'Neill HC. Proliferation of dendritic cell progenitors in long term culture is not dependent on granulocyte macrophage-colony stimulating factor. Exp Hematol 2000; 28:193-202. [PMID: 10706075 DOI: 10.1016/s0301-472x(99)00146-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
UNLABELLED A unique long term culture (LTC) system has been developed which supports the production of dendritic cells (DC). Cell production is dependent on a stromal cell layer derived from murine spleen. This LTC system produces a high turnover of non-adherent cells that express DC morphology, cell-surface markers, and antigen-presenting capacity. OBJECTIVE The long term production of these cells suggests that the LTC system supports hemopoiesis. It was of interest to examine the number and nature of hemopoietic progenitors present in LTC. MATERIALS AND METHODS A combination of approaches, including FACS analysis, spleen colony-forming unit assays, and in vitro colony assays were undertaken. RESULTS Pluripotent haemopoietic stem cells are not detectable among the non-adherent cell population produced in LTC. Instead, LTC support a replicating c-kit+ progenitor population, which generates only dendritic-like colonies in in vitro colony assays. In addition, this population does not respond to combinations of growth factors thought to stimulate DC proliferation, including granulocyte macrophage-colony stimulating factor (GM-CSF) and Flt3L. Production of DC occurs only in the presence of LTC-derived culture supernatant or a confluent stromal cell layer. CONCLUSIONS These results suggest that LTC contain a dendritic progenitor that is dependent upon the stromal cell network for proliferation and differentiation. The development of only DC within LTC allows easy collection of cells for experimentation. This, in combination with the fact that DC development occurs in the absence of exogenous growth factors, makes the LTC system a practical model for the study of DC function and development.
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Yan Z, Zhu L, Ni K, Ni X, Qian W. [Partial sympathectomy for treating palmar hyperhidrosis with VATS]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 2000; 38:64-6. [PMID: 11831992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To review the experience with partial sympathectomy for treating palmar hyperhidrosis with VATS. METHODS Between July 1995 and June 1999, 50 patients with palmar hyperhidrosis (26 males and 24 females, mean age 26.7 years) were operated. The major symptom was excessive sweating of hands, feet, and axcillaries, sometimes in drops. Thoracoscopy was performed under general anesthesia with a standard single-lumen endotracheal intubation with the patient in a semi-sitting position and arms stretched at 90 degrees. The approach through two small ports on the chest wall was done using VATS. As the lung was depressed by CO(2) insufflation in a low pressure, an excellent view of the upper mediastinum was obtained. Ganglia T(2) through T(4), sometimes T(5) were resected with a electrocautery probe. Bilateral procedures were completed in the same position. RESULTS All patients after operation became dry immediately after sympathetic denervation with a few minor complications. Occasional side effect was moderate compensatory sweating of the trunk. One case had recurrence but sweating was much less than before operation. CONCLUSIONS Because of excellent view of the upper mediastinum for sympathetic denervation of the hand and axcillaryies, the effect of partial sympathectomy for palmar hyperhidrosis is satisfactory and permanent.
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O'Neill HC, Ni K, Wilson H. Long-term stroma-dependent cultures are a consistent source of immunostimulatory dendritic cells. Immunol Cell Biol 1999; 77:434-41. [PMID: 10540210 DOI: 10.1046/j.1440-1711.1999.00851.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A long-term culture (LTC) system has been established that supports the continuous production of dendritic cells (DC) from haemopoietic cells present in the culture. The production of cells depends on the presence of an intact stromal cell layer containing a mixture of fibroblasts and endothelial cells. Cells are shed from foci of dividing cells in contact with the stromal cell matrix. They resemble DC in terms of morphology and cell surface marker expression. The LTC can be derived from different lymphoid tissues, but most success has been achieved with murine spleen. Different LTC vary in capacity to produce immunostimulatory DC. Some LTC produce DC that are very effective APC and can stimulate both mixed lymphocyte and antigen-specific T cell responses. The DC produced in others are weak APC. Different LTC appear to produce DC reflecting different stages of maturation or development, reflected by different phenotypic and functional characteristics. The production of cells within LTC occurs independently of added cytokines and is dependent on maintenance of the stromal cell layer and the presence of a subset of smaller progenitor cells. Long-term cultures remain a valuable source of cells for study of DC development and function.
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O'Neill HC, Jonas N, Wilson H, Ni K. Immunotherapeutic potential of dendritic cells generated in long-term stroma-dependent cultures. Cancer Biother Radiopharm 1999; 14:263-76. [PMID: 10850312 DOI: 10.1089/cbr.1999.14.263] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Long term cultures (LTC) producing dendritic cells (DC) have been established from spleen. A well developed stromal cell layer supported production of DC in numbers suitable for experimentation. Cells had obvious membrane pseudopodia and could be collected from culture every 2-3 days. Large cells produced in LTC stained with fluorescently labelled monoclonal antibodies specific for DC such as 33D1, and M1/70 which is specific for DC and myeloid cells. These staining patterns confirmed the presence of DC within the LTC population. LTC-DC were tested and shown capable of migration in vivo in B10.A(2R) mice following footpad inoculation. Most cells entered the spleen and a small number entered popliteal lymph node. LTC-DC have migratory capacity comparable with control spleen lymphocytes. LTC-DC were tested for capacity to induce an anti-tumour immune response after exposing cells to tumour cell membranes. LTC-DC pulsed with BL/VL3 tumour antigens were able to induce a BL/VL3-specific primary cytotoxic T lymphocyte (CTL) response detectable in popliteal lymph nodes and spleen of C57BL/6J mice within 6 days of priming. BL/VL3 tumour cells grew in sublethally irradiated C57BL/6J mice giving 100% mortality. Adoptive transfer of spleen cells from mice given BL/VL3 antigen-pulsed LTC-DC, two weeks previously, significantly slowed the growth of BL/VL3 tumour cells in mice. DC produced in LTC can function as antigen presenting cells (APC) when adoptively transferred into animals. Their capacity to migrate effectively, to induce a CTL response and to reduce tumour load suggests that DC grown using this in vitro system may have valuable clinical potential in humans.
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MESH Headings
- Adoptive Transfer
- Animals
- Cells, Cultured
- Coculture Techniques
- Cytotoxicity, Immunologic
- Dendritic Cells/cytology
- Dendritic Cells/immunology
- Female
- Leukemia, Experimental/immunology
- Leukemia, Experimental/therapy
- Leukemia, Radiation-Induced/immunology
- Leukemia, Radiation-Induced/therapy
- Mice
- Mice, Inbred C57BL
- Mice, Inbred Strains
- Neoplasms, Experimental/immunology
- Neoplasms, Experimental/therapy
- Spleen/cytology
- Spleen/immunology
- Stromal Cells/cytology
- T-Lymphocytes, Cytotoxic/immunology
- Thymoma/immunology
- Thymoma/therapy
- Thymus Neoplasms/immunology
- Thymus Neoplasms/therapy
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Ni K, O'Neill H. Spleen stromal cells support haemopoiesis and in vitro growth of dendritic cells from bone marrow. Br J Haematol 1999; 105:58-67. [PMID: 10233363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Long-term stroma-dependent cultures from murine spleen have been previously shown to support dendritic cell (DC) development in vitro. Secondary cultures have now been established using a splenic stromal cell layer overlaid with cells from different lymphoid sites. Cells resembling DCs can be generated in vitro from unfractionated murine lymphoid cells in the absence of added growth factors. Bone marrow (BM) cultures are the most successful but some cultures have been derived from spleen and thymus. Large numbers of mononuclear cells with dendritic morphology can be generated from BM within 2 weeks and cell production in many cultures has been maintained for at least 6 months. A significant proportion of cells binds antibodies specific for DC markers. No lymphoid cells, mast cells or granulocytes are detectable in culture by antibody and histochemical staining and light and electron microscopy. As with cells generated in primary cultures, cells grown in secondary cultures are equally potent stimulators of both syngeneic and allogeneic mixed lymphocyte reactions, confirming their function as antigen-presenting cells. They are also capable of endocytosing and presenting protein antigen to the D10.G4.1 Th2 clone and to unprimed T cells. This study confirmed the presence of DC precursors in multiple lymphoid sites which can be induced to proliferate in the presence of a spleen stromal cell monolayer. The secondary culture system provides an ideal in vitro model for investigation of the development of DC from different tissue sites. It also provides a stable and continuous resource of cells for further studies on DC development.
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Ni K, O'Neill HC. Hemopoiesis in long-term stroma-dependent cultures from lymphoid tissue: production of cells with myeloid/dendritic characteristics. In Vitro Cell Dev Biol Anim 1998; 34:298-307. [PMID: 9590503 DOI: 10.1007/s11626-998-0006-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A long-term stroma-dependent culture system (LTC) has been developed which continuously produces hemopoietic cells providing an in vitro system for the study of cell differentiation. These nonadherent cell populations contain a large subpopulation of dendritic cells (DC). LTC producing DC were easily generated from spleen, but could also be established from bone marrow (BM) and lymph node with less success. It was difficult to establish DC-producing LTC from thymus. The properties of splenic and thymic stroma have been compared. Spleen stroma developed more complicated networks of fibroblasts, endothelial cells, macrophages, and DC. Thymic stromal monolayers were dominated by epithelial cells and fibroblasts, with a lower proportion of macrophages and endothelial cells. They had a relatively sparse structure of cell networks compared with spleen stroma. Cells with dendritiform morphology first appeared in cultures by 2-3 wk. The majority of cells produced were large cells which expressed DC-specific cell surface markers, major histocompatibility complex (MHC) Class II molecules, and the CD80/CD86(B7) costimulator. A high proportion of cells also expressed myeloid cell markers. No T or B lymphoid cells or granulocytes were present in the cultures. LTC continued to produce nonadherent cells resembling myeloid/DC for long periods, even after passage of stromal cells and stem cells at about 3-4 mo. after culture establishment. The LTC system offers potential to study the in vitro differentiation of myeloid/DC.
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