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Eslamiamirabadi M, Burton JD, de Los Reyes FL, Ducoste JJ. Assessment of alternative herbicides for residential sewer root treatment and their effects on downstream treatment plant nitrification. J Environ Manage 2020; 258:110058. [PMID: 31929045 DOI: 10.1016/j.jenvman.2019.110058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 12/10/2019] [Accepted: 12/31/2019] [Indexed: 06/10/2023]
Abstract
The conveyance of wastewater in sewer pipes can be severely limited by the growth of plant roots, which can be controlled with herbicides. However, adding herbicides in sewer lines may affect downstream biological wastewater treatment processes. The effects of three herbicides (Dithiopyr, Penoxsulam, and Triclopyr) on the mortality of cottonwood tree roots and on downstream biological nitrification were determined. The results showed that Triclopyr achieved the highest root mortality (96%) followed by Penoxsulam (77%) and Dithiopyr (75%). At concentrations used at the point of application in sewer pipes, all herbicides caused nitrification inhibition and reduction in organic carbon removal in activated sludge. However, no inhibition was observed at the more diluted concentrations approximately equal to levels that may reach the wastewater treatment facility. Overall, Triclopyr appears to be the best performing herbicide with the highest root kill.
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Affiliation(s)
- M Eslamiamirabadi
- Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Mann Hall, Box 7908, Raleigh, NC, 27695, USA
| | - J D Burton
- Department of Horticultural Science, North Carolina State University, 232 Kilgore Hall, Box 7609, Raleigh, NC, 276957609, USA
| | - F L de Los Reyes
- Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Mann Hall, Box 7908, Raleigh, NC, 27695, USA
| | - J J Ducoste
- Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Mann Hall, Box 7908, Raleigh, NC, 27695, USA.
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Affiliation(s)
- W. M. Ingledew
- Agricultural Microbiology Section, Dairy and Food Science Department, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 0W0
| | - J. D. Burton
- Agricultural Microbiology Section, Dairy and Food Science Department, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 0W0
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Burton JD, Ingledew WM(M. Antifoams for Use in Microbial Analysis by Membrane Filtration. Journal of the American Society of Brewing Chemists 2018. [DOI: 10.1094/asbcj-38-0160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- J. D. Burton
- Agricultural Microbiology Section, Dairy and Food Science Department, University of Saskatchewa, Saskatoon, Canada S7N 0W0
| | - W. M. (Mike) Ingledew
- Agricultural Microbiology Section, Dairy and Food Science Department, University of Saskatchewa, Saskatoon, Canada S7N 0W0
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Ingledew WM, Burton JD, Hysert DW, Van Gheluwe G. Membrane Filtration: Survival of Brewing Microbes on the Membrane during Storage at Reduced Humidities. Journal of the American Society of Brewing Chemists 2018. [DOI: 10.1094/asbcj-38-0125] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- W. M. Ingledew
- Agricultural Microbiology Section, Dairy and Food Science Department, University of Saskatchewa, Saskatoon, Canada S7N 0W0
| | - J. D. Burton
- Agricultural Microbiology Section, Dairy and Food Science Department, University of Saskatchewa, Saskatoon, Canada S7N 0W0
| | - D. W. Hysert
- Molson Breweries of Canada Ltd., Montreal, Quebec, Canada H2L 2R5
| | - G. Van Gheluwe
- Molson Breweries of Canada Ltd., Montreal, Quebec, Canada H2L 2R5
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Abstract
Topological insulators are very interesting from a fundamental point of view, and their unique properties may be useful for electronic and spintronic device applications. From the point of view of applications it is important to understand the decay behavior of carriers injected in the band gap of the topological insulator, which is determined by its complex band structure (CBS). Using first-principles calculations, we investigate the dispersion and symmetry of the complex bands of Bi2Se3 family of three-dimensional topological insulators. We compare the CBS of a band insulator and a topological insulator and follow the CBS evolution in both when the spin-orbit interaction is turned on. We find significant differences in the CBS linked to the topological band structure. In particular, our results demonstrate that the evanescent states in Bi2Se3 are non-trivially complex, i.e. contain both the real and imaginary contributions. This explains quantitatively the oscillatory behavior of the band gap obtained from Bi2Se3 (0 0 0 1) slab calculations.
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Affiliation(s)
- J Betancourt
- Department of Physics and Astronomy, University of Puerto Rico, San Juan, PR 00931, USA
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Dang X, Burton JD, Tsymbal EY. Magnetic gating of a 2D topological insulator. J Phys Condens Matter 2016; 28:38LT01. [PMID: 27437829 DOI: 10.1088/0953-8984/28/38/38lt01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Deterministic control of transport properties through manipulation of spin states is one of the paradigms of spintronics. Topological insulators offer a new playground for exploring interesting spin-dependent phenomena. Here, we consider a ferromagnetic 'gate' representing a magnetic adatom coupled to the topologically protected edge state of a two-dimensional (2D) topological insulator to modulate the electron transmission of the edge state. Due to the locked spin and wave vector of the transport electrons the transmission across the magnetic gate depends on the mutual orientation of the adatom magnetic moment and the current. If the Fermi energy matches an exchange-split bound state of the adatom, the electron transmission can be blocked due to the full back scattering of the incident wave. This antiresonance behavior is controlled by the adatom magnetic moment orientation so that the transmission of the edge state can be changed from 1 to 0. Expanding this consideration to a ferromagnetic gate representing a 1D chain of atoms shows a possibility to control the spin-dependent current of a strip of a 2D topological insulator by magnetization orientation of the ferromagnetic gate.
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Affiliation(s)
- Xiaoqian Dang
- Department of Physics and Astronomy & Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, NE 68588-0299, USA
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Liu X, Burton JD, Tsymbal EY. Publisher's Note: Enhanced Tunneling Electroresistance in Ferroelectric Tunnel Junctions due to the Reversible Metallization of the Barrier [Phys. Rev. Lett. 116, 197602 (2016)]. Phys Rev Lett 2016; 116:209902. [PMID: 27258891 DOI: 10.1103/physrevlett.116.209902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Indexed: 06/05/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.116.197602.
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Liu X, Burton JD, Tsymbal EY. Enhanced Tunneling Electroresistance in Ferroelectric Tunnel Junctions due to the Reversible Metallization of the Barrier. Phys Rev Lett 2016; 116:197602. [PMID: 27232046 DOI: 10.1103/physrevlett.116.197602] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Indexed: 06/05/2023]
Abstract
Realizing a large tunneling electroresistance (TER) effect is crucial for device application of ferroelectric tunnel junctions (FTJs). FTJs are typically composed of a thin ferroelectric layer sandwiched by two metallic electrodes, where TER generally results from the dependence of the effective tunneling barrier height on the ferroelectric polarization. Since the resistance depends exponentially not only on barrier height but also on barrier width, TER is expected to be greatly enhanced when one of the electrodes is a semiconductor where the depletion region near the interface can be controlled via ferroelectric polarization. To explore this possibility, we perform studies of SrRuO_{3}/BaTiO_{3}/n-SrTiO_{3} FTJs, where n-SrTiO_{3} is an electron doped SrTiO_{3} electrode, using first-principles density functional theory. Our studies reveal that, in addition to modulation of the depletion region in n-SrTiO_{3}, the BaTiO_{3} barrier layer becomes conducting near the interface for polarization pointing into n-SrTiO_{3}, leading to dramatic enhancement of TER. The effect is controlled by the band alignment between the semiconductor and the ferroelectric insulator and opens the way for experimental realization of enhanced TER in FTJs through the choice of a semiconducting electrode and interface engineering.
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Affiliation(s)
- Xiaohui Liu
- Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588-0299, USA
| | - J D Burton
- Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588-0299, USA
| | - Evgeny Y Tsymbal
- Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588-0299, USA
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Rajapitamahuni A, Zhang L, Koten MA, Singh VR, Burton JD, Tsymbal EY, Shield JE, Hong X. Giant Enhancement of Magnetic Anisotropy in Ultrathin Manganite Films via Nanoscale 1D Periodic Depth Modulation. Phys Rev Lett 2016; 116:187201. [PMID: 27203341 DOI: 10.1103/physrevlett.116.187201] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Indexed: 06/05/2023]
Abstract
The relatively low magnetocrystalline anisotropy (MCA) in strongly correlated manganites (La,Sr)MnO_{3} has been a major hurdle for implementing them in spintronic applications. Here we report an unusual, giant enhancement of in-plane MCA in 6 nm La_{0.67}Sr_{0.33}MnO_{3} (LSMO) films grown on (001) SrTiO_{3} substrates when the top 2 nm is patterned into periodic stripes of 100 or 200 nm width. Planar Hall effect measurements reveal an emergent uniaxial anisotropy superimposed on one of the original biaxial easy axes for unpatterned LSMO along ⟨110⟩ directions, with a 50-fold enhanced anisotropy energy density of 5.6×10^{6} erg/cm^{3} within the nanostripes, comparable to the value for cobalt. The magnitude and direction of the uniaxial anisotropy exclude shape anisotropy and the step edge effect as its origin. High resolution transmission electron microscopy studies reveal a nonequilibrium strain distribution and drastic suppression in the c-axis lattice constant within the nanostructures, which is the driving mechanism for the enhanced uniaxial MCA, as suggested by first-principles density functional calculations.
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Affiliation(s)
- A Rajapitamahuni
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299, USA
| | - L Zhang
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299, USA
| | - M A Koten
- Department of Mechanical & Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299, USA
| | - V R Singh
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299, USA
| | - J D Burton
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299, USA
| | - E Y Tsymbal
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299, USA
- Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299, USA
| | - J E Shield
- Department of Mechanical & Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299, USA
- Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299, USA
| | - X Hong
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299, USA
- Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299, USA
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11
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Dang X, Burton JD, Tsymbal EY. Local currents in a 2D topological insulator. J Phys Condens Matter 2015; 27:505301. [PMID: 26610145 DOI: 10.1088/0953-8984/27/50/505301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Symmetry protected edge states in 2D topological insulators are interesting both from the fundamental point of view as well as from the point of view of potential applications in nanoelectronics as perfectly conducting 1D channels and functional elements of circuits. Here using a simple tight-binding model and the Landauer-Büttiker formalism we explore local current distributions in a 2D topological insulator focusing on effects of non-magnetic impurities and vacancies as well as finite size effects. For an isolated edge state, we show that the local conductance decays into the bulk in an oscillatory fashion as explained by the complex band structure of the bulk topological insulator. We demonstrate that although the net conductance of the edge state is topologically protected, impurity scattering leads to intricate local current patterns. In the case of vacancies we observe vortex currents of certain chirality, originating from the scattering of current-carrying electrons into states localized at the edges of hollow regions. For finite size strips of a topological insulator we predict the formation of an oscillatory band gap in the spectrum of the edge states, the emergence of Friedel oscillations caused by an open channel for backscattering from an impurity and antiresonances in conductance when the Fermi energy matches the energy of the localized state created by an impurity.
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Affiliation(s)
- Xiaoqian Dang
- Department of Physics and Astronomy & Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588-0299, USA
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12
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Sharma P, Ryu S, Burton JD, Paudel TR, Bark CW, Huang Z, Tsymbal EY, Catalan G, Eom CB, Gruverman A. Mechanical Tuning of LaAlO3/SrTiO3 Interface Conductivity. Nano Lett 2015; 15:3547-3551. [PMID: 25860855 DOI: 10.1021/acs.nanolett.5b01021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In recent years, complex-oxide heterostructures and their interfaces have become the focus of significant research activity, primarily driven by the discovery of emerging states and functionalities that open up opportunities for the development of new oxide-based nanoelectronic devices. The highly conductive state at the interface between insulators LaAlO3 and SrTiO3 is a prime example of such emergent functionality, with potential application in high electron density transistors. In this report, we demonstrate a new paradigm for voltage-free tuning of LaAlO3/SrTiO3 (LAO/STO) interface conductivity, which involves the mechanical gating of interface conductance through stress exerted by the tip of a scanning probe microscope. The mechanical control of channel conductivity and the long retention time of the induced resistance states enable transistor functionality with zero gate voltage.
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Affiliation(s)
| | - S Ryu
- ‡Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | | | | | - C W Bark
- ‡Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | | | | | - G Catalan
- ∥ICREA-Institut Catala de Recerca i Estudis Avançats, Barcelona, Spain
- ⊥ICN2-Institut Catala de Nanociencia i Nanotecnologia, Campus de Bellaterra, Barcelona, Spain
| | - C B Eom
- ‡Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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13
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Liu X, Burton JD, Zhuravlev MY, Tsymbal EY. Electric control of spin injection into a ferroelectric semiconductor. Phys Rev Lett 2015; 114:046601. [PMID: 25679900 DOI: 10.1103/physrevlett.114.046601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Indexed: 06/04/2023]
Abstract
Electric-field control of spin-dependent properties has become one of the most attractive phenomena in modern materials research due to the promise of new device functionalities. One of the paradigms in this approach is to electrically toggle the spin polarization of carriers injected into a semiconductor using ferroelectric polarization as a control parameter. Using first-principles density-functional calculations, we explore the effect of ferroelectric polarization of electron-doped BaTiO3 (n-BaTiO3) on the spin-polarized transmission across the SrRuO3/n-BaTiO3(001) interface. Our study reveals that, in this system, the interface transmission is negatively spin polarized and that ferroelectric polarization reversal leads to a change in the transport spin polarization from -65% to -98%. Analytical model calculations demonstrate that this is a general effect for ferromagnetic-metal-ferroelectric-semiconductor systems and, furthermore, that ferroelectric modulation can even reverse the sign of spin polarization. The predicted effect provides a nonvolatile mechanism to electrically control spin injection in semiconductor-based spintronics devices.
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Affiliation(s)
- Xiaohui Liu
- Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588-0299, USA
| | - J D Burton
- Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588-0299, USA
| | - M Ye Zhuravlev
- Kurnakov Institute for General and Inorganic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russia and Faculty of Liberal Arts and Sciences, St. Petersburg State University, 190000 St. Petersburg, Russia
| | - Evgeny Y Tsymbal
- Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588-0299, USA
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Gai Z, Lin W, Burton JD, Fuchigami K, Snijders PC, Ward TZ, Tsymbal EY, Shen J, Jesse S, Kalinin SV, Baddorf AP. Chemically induced Jahn-Teller ordering on manganite surfaces. Nat Commun 2014; 5:4528. [PMID: 25058540 DOI: 10.1038/ncomms5528] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 06/26/2014] [Indexed: 12/27/2022] Open
Abstract
Physical and electrochemical phenomena at the surfaces of transition metal oxides and their coupling to local functionality remains one of the enigmas of condensed matter physics. Understanding the emergent physical phenomena at surfaces requires the capability to probe the local composition, map order parameter fields and establish their coupling to electronic properties. Here we demonstrate that measuring the sub-30-pm displacements of atoms from high-symmetry positions in the atomically resolved scanning tunnelling microscopy allows the physical order parameter fields to be visualized in real space on the single-atom level. Here, this local crystallographic analysis is applied to the in-situ-grown manganite surfaces. In particular, using direct bond-angle mapping we report direct observation of structural domains on manganite surfaces, and trace their origin to surface-chemistry-induced stabilization of ordered Jahn-Teller displacements. Density functional calculations provide insight into the intriguing interplay between the various degrees of freedom now resolved on the atomic level.
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Affiliation(s)
- Zheng Gai
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Wenzhi Lin
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J D Burton
- Nebraska Center for Materials and Nanoscience and Department of Physics and Astronomy, University of Nebraska Lincoln, Lincoln, Nebraska 68588, USA
| | - K Fuchigami
- Research Laboratory, IHI Corporation, Yokohama, Kanagawa 235-8501, Japan
| | - P C Snijders
- 1] Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA [2] Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996, USA
| | - T Z Ward
- Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Evgeny Y Tsymbal
- Nebraska Center for Materials and Nanoscience and Department of Physics and Astronomy, University of Nebraska Lincoln, Lincoln, Nebraska 68588, USA
| | - J Shen
- 1] Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996, USA [2] State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Stephen Jesse
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Sergei V Kalinin
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Arthur P Baddorf
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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Yin YW, Burton JD, Kim YM, Borisevich AY, Pennycook SJ, Yang SM, Noh TW, Gruverman A, Li XG, Tsymbal EY, Li Q. Enhanced tunnelling electroresistance effect due to a ferroelectrically induced phase transition at a magnetic complex oxide interface. Nat Mater 2013; 12:397-402. [PMID: 23416728 DOI: 10.1038/nmat3564] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 01/07/2013] [Indexed: 06/01/2023]
Abstract
The range of recently discovered phenomena in complex oxide heterostructures, made possible owing to advances in fabrication techniques, promise new functionalities and device concepts. One issue that has received attention is the bistable electrical modulation of conductivity in ferroelectric tunnel junctions (FTJs) in response to a ferroelectric polarization of the tunnelling barrier, a phenomenon known as the tunnelling electroresistance (TER) effect. Ferroelectric tunnel junctions with ferromagnetic electrodes allow ferroelectric control of the tunnelling spin polarization through the magnetoelectric coupling at the ferromagnet/ferroelectric interface. Here we demonstrate a significant enhancement of TER due to a ferroelectrically induced phase transition at a magnetic complex oxide interface. Ferroelectric tunnel junctions consisting of BaTiO3 tunnelling barriers and La(0.7)Sr(0.3)MnO3 electrodes exhibit a TER enhanced by up to ~10,000% by a nanometre-thick La(0.5)Ca(0.5)MnO3 interlayer inserted at one of the interfaces. The observed phenomenon originates from the metal-to-insulator phase transition in La(0.5)Ca(0.5)MnO3, driven by the modulation of carrier density through ferroelectric polarization switching. Electrical, ferroelectric and magnetoresistive measurements combined with first-principles calculations provide evidence for a magnetoelectric origin of the enhanced TER, and indicate the presence of defect-mediated conduction in the FTJs. The effect is robust and may serve as a viable route for electronic and spintronic applications.
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Ingledew WM, Sivaswamy G, Burton JD. THE API 20E MICROTUBE SYSTEM FOR RAPID IDENTIFICATION OF GRAM NEGATIVE BREWERY BACTERIA. Journal of the Institute of Brewing 2013. [DOI: 10.1002/j.2050-0416.1980.tb06855.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Wang Y, Liu X, Burton JD, Jaswal SS, Tsymbal EY. Ferroelectric instability under screened Coulomb interactions. Phys Rev Lett 2012; 109:247601. [PMID: 23368377 DOI: 10.1103/physrevlett.109.247601] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Indexed: 06/01/2023]
Abstract
We explore the effect of charge carrier doping on ferroelectricity using density functional calculations and phenomenological modeling. By considering a prototypical ferroelectric material, BaTiO(3), we demonstrate that ferroelectric displacements are sustained up to the critical concentration of 0.11 electron per unit cell volume. This result is consistent with experimental observations and reveals that the ferroelectric phase and conductivity can coexist. Our investigations show that the ferroelectric instability requires only a short-range portion of the Coulomb force with an interaction range of the order of the lattice constant. These results provide a new insight into the origin of ferroelectricity in displacive ferroelectrics and open opportunities for using doped ferroelectrics in novel electronic devices.
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Affiliation(s)
- Yong Wang
- Department of Physics and Astronomy & Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588, USA.
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Abstract
Engineered heterostructures designed for electric control of magnetic properties, the so-called magnetoelectric interfaces, present a novel route towards using the spin degree of freedom in electronic devices. Here, we review how a subset of such interfaces, namely ferromagnet-ferroelectric heterostructures, display electronically mediated control of magnetism and, in particular, emphasis is placed on how these effects manifest themselves as detectable spin-dependent transport phenomena. Examples of these effects are given for a variety of material systems on the basis of ferroelectric oxides, manganese and ruthenium magnetic complex oxides and elemental ferromagnetic metals. Results from both theory and experiment are discussed.
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Affiliation(s)
- J D Burton
- Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, 68588-0299, USA
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Wu M, Burton JD, Tsymbal EY, Zeng XC, Jena P. Multiferroic Materials Based on Organic Transition-Metal Molecular Nanowires. J Am Chem Soc 2012; 134:14423-9. [DOI: 10.1021/ja304199x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Menghao Wu
- Department of Physics, Virginia Commonwealth University, Richmond, Virginia
23284, United States
| | | | | | | | - Puru Jena
- Department of Physics, Virginia Commonwealth University, Richmond, Virginia
23284, United States
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Lukashev PV, Burton JD, Jaswal SS, Tsymbal EY. Ferroelectric control of the magnetocrystalline anisotropy of the Fe/BaTiO(3)(001) interface. J Phys Condens Matter 2012; 24:226003. [PMID: 22551672 DOI: 10.1088/0953-8984/24/22/226003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Density-functional calculations are employed to investigate the effect of ferroelectric polarization of BaTiO(3) on the magnetocrystalline anisotropy of the Fe /BaTiO(3)(001) interface. It is found that the interface magnetocrystalline anisotropy energy changes from 1.33 to 1.02 erg cm (-2) when the ferroelectric polarization is reversed. This strong magnetoelectric coupling is explained in terms of the changing population of the Fe 3d orbitals at the Fe/BaTiO(3) interface driven by polarization reversal. Our results indicate that the electronically assisted magnetoelectric effects at the ferromagnetic/ferroelectric interfaces may be a viable alternative to the strain mediated coupling in related heterostructures and the electric field-induced effects on the interface magnetic anisotropy in ferromagnet/dielectric structures.
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Affiliation(s)
- Pavel V Lukashev
- Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, NE 68588-0299, USA.
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Lu H, Liu X, Burton JD, Bark CW, Wang Y, Zhang Y, Kim DJ, Stamm A, Lukashev P, Felker DA, Folkman CM, Gao P, Rzchowski MS, Pan XQ, Eom CB, Tsymbal EY, Gruverman A. Enhancement of ferroelectric polarization stability by interface engineering. Adv Mater 2012; 24:1209-1216. [PMID: 22278910 DOI: 10.1002/adma.201104398] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Revised: 12/23/2011] [Indexed: 05/31/2023]
Abstract
By using theoretical predictions based on first-principle calculations, we explore an interface engineering approach to stabilize polarization states in ferroelectric heterostructures with a thickness of just several nanometers.
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Affiliation(s)
- H Lu
- Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, NE 68588, USA
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23
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Burton JD, Tsymbal EY. Highly spin-polarized conducting state at the interface between nonmagnetic band insulators: LaAlO3/FeS2 (001). Phys Rev Lett 2011; 107:166601. [PMID: 22107410 DOI: 10.1103/physrevlett.107.166601] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Indexed: 05/31/2023]
Abstract
First-principles density functional calculations demonstrate that a spin-polarized two-dimensional conducting state can be realized at the interface between two nonmagnetic band insulators. The (001) surface of the diamagnetic insulator FeS(2) (pyrite) supports a localized surface state deriving from Fe d orbitals near the conduction band minimum. The deposition of a few unit cells of the polar perovskite oxide LaAlO(3) leads to electron transfer into these surface bands, thereby creating a conducting interface. The occupation of these narrow bands leads to an exchange splitting between the spin subbands, yielding a highly spin-polarized conducting state distinct from the rest of the nonmagnetic, insulating bulk. Such an interface presents intriguing possibilities for spintronics applications.
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Affiliation(s)
- J D Burton
- Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588-0299, USA.
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24
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Burton JD, Tsymbal EY. Giant tunneling electroresistance effect driven by an electrically controlled spin valve at a complex oxide interface. Phys Rev Lett 2011; 106:157203. [PMID: 21568608 DOI: 10.1103/physrevlett.106.157203] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Indexed: 05/30/2023]
Abstract
A giant tunneling electroresistance effect may be achieved in a ferroelectric tunnel junction by exploiting the magnetoelectric effect at the interface between the ferroelectric barrier and a magnetic La(1-x)Sr(x)MnO3 electrode. Using first-principles density-functional theory we demonstrate that a few magnetic monolayers of La(1-x)Sr(x)MnO3 near the interface act, in response to ferroelectric polarization reversal, as an atomic-scale spin valve by filtering spin-dependent current. This produces more than an order of magnitude change in conductance, and thus constitutes a giant resistive switching effect.
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Affiliation(s)
- J D Burton
- Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588-0299, USA.
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25
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López-Encarnación JM, Burton JD, Tsymbal EY, Velev JP. Organic multiferroic tunnel junctions with ferroelectric poly(vinylidene fluoride) barriers. Nano Lett 2011; 11:599-603. [PMID: 21175179 DOI: 10.1021/nl103650b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Organic materials are promising for applications in spintronics due to their long spin-relaxation times in addition to their chemical flexibility and relatively low production costs. Most studies of organic materials for spintronics focus on nonpolar dielectrics or semiconductors, serving as passive elements in spin transport devices. Here, we demonstrate that employing organic ferroelectrics, such as poly(vinylidene fluoride) (PVDF), as barriers in magnetic tunnel junctions (MTJs) allows new functionality in controlling the tunneling spin polarization via the ferroelectric polarization of the barrier. Using first-principles methods based on density functional theory we investigate the spin-resolved conductance of Co/PVDF/Co and Co/PVDF/Fe/Co MTJs as model systems. We show that these tunnel junctions exhibit multiple resistance states associated with different magnetization configurations of the electrodes and ferroelectric polarization orientations of the barrier. Our results indicate that organic ferroelectrics may open a new and promising route in organic spintronics with implications for low-power electronics and nonvolatile data storage.
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Affiliation(s)
- Juan M López-Encarnación
- Department of Physics, Institute for Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931
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26
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Borisevich AY, Chang HJ, Huijben M, Oxley MP, Okamoto S, Niranjan MK, Burton JD, Tsymbal EY, Chu YH, Yu P, Ramesh R, Kalinin SV, Pennycook SJ. Suppression of octahedral tilts and associated changes in electronic properties at epitaxial oxide heterostructure interfaces. Phys Rev Lett 2010; 105:087204. [PMID: 20868130 DOI: 10.1103/physrevlett.105.087204] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Indexed: 05/29/2023]
Abstract
Epitaxial oxide interfaces with broken translational symmetry have emerged as a central paradigm behind the novel behaviors of oxide superlattices. Here, we use scanning transmission electron microscopy to demonstrate a direct, quantitative unit-cell-by-unit-cell mapping of lattice parameters and oxygen octahedral rotations across the BiFeO3-La0.7 Sr0.3 MnO3 interface to elucidate how the change of crystal symmetry is accommodated. Combined with low-loss electron energy loss spectroscopy imaging, we demonstrate a mesoscopic antiferrodistortive phase transition near the interface in BiFeO3 and elucidate associated changes in electronic properties in a thin layer directly adjacent to the interface.
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Affiliation(s)
- A Y Borisevich
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
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27
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Burton JD, Stein R, Chandra A, Chen S, Mishra N, Shah T, Goldenberg DM. Expression of CD74 by AML blasts and cell lines, and enhanced in vitro cytotoxicity of anti-CD74 antibody after interferon-gamma (IFN-γ) treatment. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.6576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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28
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Velev JP, Duan CG, Burton JD, Smogunov A, Niranjan MK, Tosatti E, Jaswal SS, Tsymbal EY. Magnetic tunnel junctions with ferroelectric barriers: prediction of four resistance States from first principles. Nano Lett 2009; 9:427-432. [PMID: 19113889 DOI: 10.1021/nl803318d] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Magnetic tunnel junctions (MTJs), composed of two ferromagnetic electrodes separated by a thin insulating barrier layer, are currently used in spintronic devices, such as magnetic sensors and magnetic random access memories. Recently, driven by demonstrations of ferroelectricity at the nanoscale, thin-film ferroelectric barriers were proposed to extend the functionality of MTJs. Due to the sensitivity of conductance to the magnetization alignment of the electrodes (tunneling magnetoresistance) and the polarization orientation in the ferroelectric barrier (tunneling electroresistance), these multiferroic tunnel junctions (MFTJs) may serve as four-state resistance devices. On the basis of first-principles calculations, we demonstrate four resistance states in SrRuO(3)/BaTiO(3)/SrRuO(3) MFTJs with asymmetric interfaces. We find that the resistance of such a MFTJ is significantly changed when the electric polarization of the barrier is reversed and/or when the magnetizations of the electrodes are switched from parallel to antiparallel. These results reveal the exciting prospects of MFTJs for application as multifunctional spintronic devices.
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Affiliation(s)
- Julian P Velev
- Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, Nebraska 68588-0111, USA.
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29
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Gao L, Jiang X, Yang SH, Burton JD, Tsymbal EY, Parkin SSP. Bias voltage dependence of tunneling anisotropic magnetoresistance in magnetic tunnel junctions with MgO and Al2O3 tunnel barriers. Phys Rev Lett 2007; 99:226602. [PMID: 18233308 DOI: 10.1103/physrevlett.99.226602] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 07/02/2007] [Indexed: 05/25/2023]
Abstract
Tunneling anisotropic magnetoresistance (TAMR) is observed in tunnel junctions with transition metal electrodes as the moments are rotated from in-plane to out-of-plane in sufficiently large magnetic fields that the moments are nearly parallel to one another. A complex angular dependence of the tunneling resistance is found with twofold and fourfold components that vary strongly with bias voltage. Distinctly different TAMR behaviors are obtained for devices formed with highly textured crystalline MgO(001) and amorphous Al2O3 tunnel barriers. A tight-binding model shows that a fourfold angular dependence can be explained by the presence of an interface resonant state that affects the transmission of the contributing tunneling states through a spin-orbit interaction.
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Affiliation(s)
- Li Gao
- IBM Research Division, Almaden Research Center, San Jose, California 95120, USA
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30
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Burton JD, Sabirianov RF, Jaswal SS, Tsymbal EY, Mryasov ON. Magnetic moment softening and domain wall resistance in Ni nanowires. Phys Rev Lett 2006; 97:077204. [PMID: 17026271 DOI: 10.1103/physrevlett.97.077204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Indexed: 05/12/2023]
Abstract
We perform ab initio calculations of the electronic structure and conductance of atomic-size Ni nanowires with domain walls only a few atomic lattice constants wide. We show that the hybridization between noncollinear spin states leads to a reduction of the magnetic moments in the domain wall resulting in the enhancement of the domain wall resistance. Experimental studies of the magnetic moment softening may be feasible with modern techniques such as scanning tunneling spectroscopy.
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Affiliation(s)
- J D Burton
- Department of Physics and Astronomy, University of Nebraska, Lincoln, Nebraska 68588-0111, USA
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31
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Abstract
Accurate and reproducible methods for the analysis of plant allelochemicals are a requirement for the study of chemical interactions between plants. This paper describes a method for sample preparation and quantitative analysis of the allelopathic chemical content of rye (Secale cereale L.) using gas chromatography (GC). Sample preparation consists of extraction of freeze-dried rye vegetative tissue with aqueous ethanol followed by partitioning of the allelochemicals into ethyl acetate, evaporation, and derivatization using the trimethylsilylating reagent N-methyl-N-trimethylsilyltrifluoroacetamide. GC analysis of the silylated mixture was performed using flame ionization detection. This method permits analysis of all known rye allelopathic agents including 2,4-dihydroxy-1,4-benzoxazin-3-one, its corresponding glucoside, 2-benzoxazolinone, beta-hydroxybutyric acid, and beta-phenyllactic acid. Identities of all compounds were confirmed by GC/MS analysis.
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Affiliation(s)
- M M Finney
- Department of Crop Science, North Carolina State University, Raleigh, NC 27695-7620, USA
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32
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Burton JD, El-Sayah D, Cherry M, Bhargava M, Terjanian T, Odaimi M, Vesoniaraki M, Lowry J, Forte F, Friscia P. Results of a phase I/II trial of carboplatin/gemcitabine plus celecoxib for first-line treatment of stage IIIB/IV non-small cell lung cancer (NSCLC). J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.7250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
| | | | - M. Cherry
- Staten Island Univ Hosp, Staten Island, NY
| | | | | | - M. Odaimi
- Staten Island Univ Hosp, Staten Island, NY
| | | | - J. Lowry
- Staten Island Univ Hosp, Staten Island, NY
| | - F. Forte
- Staten Island Univ Hosp, Staten Island, NY
| | - P. Friscia
- Staten Island Univ Hosp, Staten Island, NY
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Burton JD, Badine E, El-Sayah D, Dib E, Forte F, Terjanian T, Odaimi M, Vesoniaraki M, Friscia P, Lowry J. Update of a phase I/II trial of carboplatin/gemcitabine plus escalating doses of celecoxib for first-line treatment of stage IIIB/IV non-small cell lung cancer (NSCLC). J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.7339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- J. D. Burton
- Staten Island University Hospital, Staten Island, NY
| | - E. Badine
- Staten Island University Hospital, Staten Island, NY
| | - D. El-Sayah
- Staten Island University Hospital, Staten Island, NY
| | - E. Dib
- Staten Island University Hospital, Staten Island, NY
| | - F. Forte
- Staten Island University Hospital, Staten Island, NY
| | - T. Terjanian
- Staten Island University Hospital, Staten Island, NY
| | - M. Odaimi
- Staten Island University Hospital, Staten Island, NY
| | | | - P. Friscia
- Staten Island University Hospital, Staten Island, NY
| | - J. Lowry
- Staten Island University Hospital, Staten Island, NY
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35
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Reddy PK, Gold DV, Cardillo TM, Goldenberg DM, Li H, Burton JD. Interferon-gamma upregulates MUC1 expression in haematopoietic and epithelial cancer cell lines, an effect associated with MUC1 mRNA induction. Eur J Cancer 2003; 39:397-404. [PMID: 12565994 DOI: 10.1016/s0959-8049(02)00700-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Epithelial mucin-1 (MUC1) is an important target antigen that it is overexpressed in both epithelial and haematological cancers including multiple myeloma (MM) and some lymphomas and leukaemias. MUC1 has adhesive and immunosuppressive properties, which may promote cancer progression. These studies evaluated the effect of IFNs on MUC1 expression, since these agents are widely used in clinical cancer therapy. MUC1 and interferon (IFN) receptor expression were measured by radioligand binding. Changes in MUC1 mRNA levels in response to IFN-gamma were assessed by semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). IFN-gamma was found to be a more potent inducer of MUC1 expression than IFN-alpha. 125I-IFN binding studies indicated that both IFN receptors were expressed in most of the cell lines. With IFN-gamma treatment, there was upregulation of MUC1 mRNA. IFN-gamma has a more consistent and more potent effect upon MUC1 induction than IFN-alpha. The ability to upregulate MUC1 across a broad range of cancer types by a clinically available cytokine, IFN-gamma, has important implications for enhancing immunotherapeutic approaches targeting MUC1.
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Affiliation(s)
- P K Reddy
- Center for Molecular Medicine and Immunology, 520 Belleville Avenue, Belleville, NJ 07109, USA
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36
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Jarvie HP, Neal C, Tappin AD, Burton JD, Hill L, Neal M, Harrow M, Hopkins R, Watts C, Wickham H. Riverine inputs of major ions and trace elements to the tidal reaches of the River Tweed, UK. Sci Total Environ 2000; 251-252:55-81. [PMID: 10847153 DOI: 10.1016/s0048-9697(00)00414-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
This paper examines spatial and temporal variability in freshwater inputs of trace elements and major ions to the tidal reaches of the River Tweed. The relationships between concentrations of major ions and trace elements (in dissolved and acid-available particulate forms) and flow are examined, and a simple two-component endmember mixing analysis performed to link river water chemistry to catchment sources, and to identify whether within-river processes modify concentrations to produce non-conservative behaviour. The results indicate that most dissolved major ions and trace elements behave conservatively in the lower reaches of the River Tweed, the variability in concentrations being dominated by hydrology and the existence of different high-flow and low-flow endmember runoff chemistries. This suggests that the variability in concentration of most dissolved trace elements and major ions in the lower Tweed can be modelled using simple mixing relationships. However, the relationships between pH, Ca, Mg and Gran alkalinity show pronounced non-conservative behaviour, indicating the importance of understanding within-river process for modelling these determinants. The non-conservative behaviour identified is related to biological controls and the resultant diurnal variations in pH which promote daytime removal of Ca from solution by precipitation of calcium carbonate (and corresponding removal of Mg by co-precipitation) during extreme low-flow conditions and algal blooms during the summer.
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Tagaya Y, Burton JD, Miyamoto Y, Waldmann TA. Identification of a novel receptor/signal transduction pathway for IL-15/T in mast cells. EMBO J 1996; 15:4928-39. [PMID: 8890166 PMCID: PMC452230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Interleukin-15/T(IL-15) is a growth factor that utilizes IL-2 receptor (IL-2R) components in addition to its private binding protein IL-15R(alpha) in T-cells. Here, we report that IL-15 induces mast cell proliferation in the absence of IL-2R alpha and beta. Using transfectants of these cells with a cytoplasmic-truncated mutant of gamma(c), we demonstrated that IL-15 signaling in mast cells does not involve gamma(c). Cross-linking of mast cells with [(125)I]IL-15 revealed a 60-65 kDa IL-15 binding protein that is distinct from known components of T-cell IL-15 receptors. Mast cell IL-15 receptors recruit JAK-2 and STAT-5, instead of JAK1/3 and STAT3/5 that are activated in T-cells. Thus IL-15 is a mast cell growth factor that utilizes a novel receptor and distinct signaling pathway.
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Affiliation(s)
- Y Tagaya
- Metabolism Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1374, USA
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Bamford RN, Battiata AP, Burton JD, Sharma H, Waldmann TA. Interleukin (IL) 15/IL-T production by the adult T-cell leukemia cell line HuT-102 is associated with a human T-cell lymphotrophic virus type I region /IL-15 fusion message that lacks many upstream AUGs that normally attenuates IL-15 mRNA translation. Proc Natl Acad Sci U S A 1996; 93:2897-902. [PMID: 8610139 PMCID: PMC39731 DOI: 10.1073/pnas.93.7.2897] [Citation(s) in RCA: 172] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We reported previously that the human T-cell lymphotrophic virus type I (HTLV-I)-associated adult T-cell leukemia line HuT-102 produces a cytokine designated interleukin (IL) T that requires interleukin (IL) 2 receptor beta-subunit expression for its action. Using anti-cytokine antibodies, we demonstrated that IL-T is identical to the simultaneously described IL-15. When compared to activated monocytes, IL-15 mRNA expression was 6- to 10-fold greater in HuT-102 cells. The predominant IL-15 message from HuT-102 is a chimeric mRNA joining a segment of the R region of the long terminal repeat of HTLV-I and the 5'-untranslated region (UTR) of IL-15. Normally, by alternative splicing, this 118-nucleotide R element represents the most 5' region of several HTLV-I transcripts including tax, rex, and env. The introduction of the R element eliminated over 200 nucleotides of the IL-15 5'-UTR, including 8 of 10 upstream AUGs that are present in normal IL-15 messages. On analysis of the 5'-UTR of normal IL-15, we demonstrated that the presence of these 10 upstream AUGs interferes with IL-15 mRNA translation. Thus, IL-15 synthesis by the adult T-cell leukemia line HuT- 102 involves an increase in IL-15 mRNA transcription and translation secondary to the production of an HTLV-I R element fusion message that lacks many upstream AUGs.
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Affiliation(s)
- R N Bamford
- Metabolism Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1374, USA
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40
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Tendler CL, Burton JD, Jaffe J, Danielpour D, Charley M, McCoy JP, Pittelkow MR, Waldmann TA. Abnormal cytokine expression in Sézary and adult T-cell leukemia cells correlates with the functional diversity between these T-cell malignancies. Cancer Res 1994; 54:4430-5. [PMID: 7913876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The Sézary syndrome (SzS) and adult T-cell leukemia (ATL) are malignant proliferations of mature T-lymphocytes that possess distinct functions. Sézary cells function as helper cells, whereas ATL cells are usually suppressor effectors. Although phenotypically similar (CD4+/CD7-/CD8-), these functional differences between the T-cell lymphoproliferative disorders suggest different patterns of cytokine expression. We wished to delineate the cytokine mechanisms potentially underlying the diverse functional characteristics of SzS and ATL. Therefore, we analyzed the expression of interleukins (IL) 2, 4, and 5, gamma-interferon, and transforming growth factor beta 1 in the highly purified leukemic T-cells from 5 SzS and 5 ATL patients. Decreased mRNA and protein levels of IL-2, gamma-interferon, and IL-5 were detected in mitogen-stimulated ATL and SzS cells when compared to similarly cultured normal CD4+ cells. In contrast, IL-4 production was markedly up-regulated in the leukemic cells of 4/5 SzS patients as compared to ATL and normal controls. Finally, fresh ATL cells secreted higher levels of transforming growth factor beta 1 into the culture medium than the malignant T-cells from SzS patients. Collectively these results suggest that, similar to the murine CD4-expressing T-cell subsets Th1 and Th2, different cytokine profiles exist in a human population of CD4+ T-cells. Moreover, the distinct patterns of IL-4 and transforming growth factor beta 1 expression by SzS and ATL cells, respectively, are most consistent with the functional differences (i.e., helper versus suppressor activity) between these T-cell malignancies and thus may play important roles in the pathogenesis of the paraneoplastic features associated with these two leukemias.
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Affiliation(s)
- C L Tendler
- Division of Pediatric Oncology, Mount Sinai School of Medicine, New York, New York 10029-6574
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41
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Bamford RN, Grant AJ, Burton JD, Peters C, Kurys G, Goldman CK, Brennan J, Roessler E, Waldmann TA. The interleukin (IL) 2 receptor beta chain is shared by IL-2 and a cytokine, provisionally designated IL-T, that stimulates T-cell proliferation and the induction of lymphokine-activated killer cells. Proc Natl Acad Sci U S A 1994; 91:4940-4. [PMID: 8197161 PMCID: PMC43905 DOI: 10.1073/pnas.91.11.4940] [Citation(s) in RCA: 317] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Late-phase human T-cell lymphotropic virus I-associated adult T-cell leukemia cells express IL-2 receptors (IL-2R) but no longer produce IL-2. We have reported that the IL-2-independent adult T-cell leukemia line HuT-102 secretes a cytokine, provisionally designated IL-T, that stimulates T-cell proliferation and lymphokine-activated killer cell activity. Stimulation of proliferation of the cytokine-dependent human T-cell line Kit-225 mediated by HuT-102-conditioned medium or by 3200-fold-purified IL-T was not blocked by the addition of antibodies against IL-2 or IL-2R alpha subunit. However, IL-T-mediated stimulation of this human T-cell line was inhibited by addition of Mik-beta 1, an antibody that binds specifically to IL-2R beta subunit. In addition, the activation of large granular lymphocytes to lymphokine-activated killer cells mediated by IL-T-containing conditioned medium was not blocked by antibodies directed toward IL-2 or IL-2 alpha but was inhibited by an antibody to IL-2R beta, suggesting the requirement of this receptor subunit for IL-T action. This conclusion was confirmed using an IL-3-dependent murine myeloid precursor cell line, 32D, that expresses IL-2R alpha and IL-2R gamma, but not IL-2R beta. Neither IL-2 nor IL-T stimulated 32D cell proliferation. However, after transfection with the gene encoding human IL-2R beta, 32D beta cells proliferated on addition of either cytokine. The IL-T-mediated stimulation of 32D beta proliferation was inhibited by an anti-IL-2R beta antibody but not by an anti-IL-2 antibody. Thus, the IL-T-mediated stimulation of T-cell and lymphokine-activated killer cell activation requires the expression of the IL-2R beta subunit.
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Affiliation(s)
- R N Bamford
- Metabolism Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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42
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Burton JD, Bamford RN, Peters C, Grant AJ, Kurys G, Goldman CK, Brennan J, Roessler E, Waldmann TA. A lymphokine, provisionally designated interleukin T and produced by a human adult T-cell leukemia line, stimulates T-cell proliferation and the induction of lymphokine-activated killer cells. Proc Natl Acad Sci U S A 1994; 91:4935-9. [PMID: 8197160 PMCID: PMC43904 DOI: 10.1073/pnas.91.11.4935] [Citation(s) in RCA: 296] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
In early phases of human T-cell lymphotrophic virus I-induced adult T-cell leukemia (ATL), the malignant cell proliferation is associated with an autocrine process involving coordinate expression of interleukin (IL) 2 and its receptor. However, during late-phase ATL, leukemic cells no longer produce IL-2 yet continue to express high-affinity IL-2 receptors. During studies to define pathogenic mechanisms that underlie this IL-2-independent proliferation, we demonstrated that the ATL cell line HuT-102 secretes a lymphokine, provisionally designated IL-T, that stimulates T-cell proliferation and the induction of lymphokine-activated killer cells. Conditioned medium from HuT-102, when added to the IL-2-dependent CTLL-2 line, yielded a stimulation index of 230. Since CTLL-2 was purported to be IL-2-specific, we performed a number of studies to exclude IL-2 production by HuT-102. Stimulation of CTLL-2 cells by HuT-102-conditioned medium was not meaningfully inhibited by addition of an antiserum to IL-2. Furthermore, uninduced HuT-102 cells did not express mRNA encoding IL-2 as assessed by Northern blot analysis. No biological activity on CTLL-2 cells was mediated by purified IL-1, IL-3, IL-4, IL-5, IL-6, IL-7, IL-9, IL-10, IL-12, IL-13, or granulocyte/macrophage colony-stimulating factor, thus differentiating these factors from IL-T. Based on preliminary biochemical data, IL-T is a protein with a pI value of 4.5 and a molecular mass in SDS gels of 14 kDa. In addition to its action on CTLL-2 cells, 3200-fold-purified IL-T stimulated proliferation of the human cytokine-dependent T-cell line Kit-225. Furthermore, addition of IL-T enhanced cytotoxic activity of large granular lymphocytes (i.e., induced lymphokine-activated killer cells). Thus, IL-T is a lymphokine that plays a role in T-cell proliferation and induction of lymphokine-activated killer cells. Furthermore, IL-T may contribute to IL-2-independent proliferation of select ATL cells and lines.
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Affiliation(s)
- J D Burton
- Metabolism Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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Tendler CL, Greenberg SJ, Burton JD, Danielpour D, Kim SJ, Blattner WA, Manns A, Waldmann TA. Cytokine induction in HTLV-I associated myelopathy and adult T-cell leukemia: alternate molecular mechanisms underlying retroviral pathogenesis. J Cell Biochem 1991; 46:302-11. [PMID: 1757474 DOI: 10.1002/jcb.240460405] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The human T-cell lymphotropic virus type I (HTLV-I) is capable of inducing a variety of host cellular genes including many of the cytokines responsible for immune regulation and osteoclast activation. This derangement in cytokine expression may contribute to the panoply of disease states associated with HTLV-I infection such as the adult T-cell leukemia (ATL) and HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP). We wished to determine if there was a correlation between the expression of an array of cytokines and the diverse clinical manifestations of ATL and HAM/TSP. Utilizing the techniques of specific mRNA amplification by the polymerase chain reaction (PCR) as well as Northern blotting, we analyzed the ex vivo mRNA expression of gamma-interferon (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and transforming growth factor-beta 1 (TGF-beta 1) in the peripheral blood of HAM/TSP and ATL patients as well as asymptomatic seropositive carriers. IFN-gamma, TNF-alpha, and IL-1 beta transcripts were up-regulated in patients with HAM/TSP and seropositive carriers when compared to their levels in ATL and normal controls. In contrast, the ATL patients constitutively expressed higher levels of TGF-beta 1 mRNA than HAM/TSP and seropositive carriers. In addition, TNF-alpha and IL-1 beta serum levels were elevated in HAM/TSP, but not in ATL patients nor seropositive carriers. However, the circulating leukemic cells from ATL patients secreted increased levels of TGF-beta 1 protein into the culture medium than T-cells derived from HAM/TSP patients. Collectively these results suggest that induction of IFN-gamma, TNF-alpha, and IL-1 beta in HAM/TSP may initiate an inflammatory cascade with subsequent events leading to immune mediated destruction of the central nervous system in these patients. Expression of osteoclast activators such as TNF-alpha and IL-1 beta is not associated with hypercalcemia in ATL. Finally, impaired cellular and humoral immune responses present in ATL, but not in HAM/TSP, may be related to elevated levels of TGF-beta 1 produced by the leukemic cells. These differences in retroviral-induced host cytokine expression in ATL and HAM/TSP suggest alternate roles in disease pathogenesis.
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Affiliation(s)
- C L Tendler
- Metabolism Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892
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Tendler CL, Greenberg SJ, Blattner WA, Manns A, Murphy E, Fleisher T, Hanchard B, Morgan O, Burton JD, Nelson DL. Transactivation of interleukin 2 and its receptor induces immune activation in human T-cell lymphotropic virus type I-associated myelopathy: pathogenic implications and a rationale for immunotherapy. Proc Natl Acad Sci U S A 1990; 87:5218-22. [PMID: 2367534 PMCID: PMC54293 DOI: 10.1073/pnas.87.13.5218] [Citation(s) in RCA: 145] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A state of T-cell activation, reflected by a marked degree of spontaneous proliferation in vitro, exists among patients with human T-cell lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) but not in those with retroviral-induced adult T-cell leukemia (ATL). We wished to define the mechanism by which the immune activation of circulating cells from HAM/TSP is driven, thus gaining insight into the pathogenesis of this HTLV-I-associated disease. By using a modification of the polymerase chain reaction, we compared the levels of interleukin 2 (IL-2) and IL-2 receptor alpha chain (IL-2R alpha) mRNA expression to the transcription of the HTLV-I transactivator gene, pX, in peripheral blood mononuclear cells of HAM/TSP and ATL patients as well as seropositive carriers. Up-regulation of IL-2 and IL-2R alpha transcripts was detected in HAM/TSP and seropositive carriers that paralleled the coordinate mRNA expression of the pX transactivator. In addition, IL-2 and soluble IL-2R alpha serum levels in HAM/TSP and seropositive carriers were elevated. Despite markedly elevated levels of soluble IL-2R alpha in ATL, transcripts for IL-2 and pX were not demonstrable in the circulating cells. Finally, the marked degree of in vitro spontaneous proliferation present in HAM/TSP was profoundly inhibited by specific anti-IL-2R or anti-IL-2 blocking antibodies. Collectively, these results suggest that immune activation in HAM/TSP, in contrast to ATL, is virally driven by the transactivation and coordinate expression of IL-2 and IL-2R alpha. This deregulated autocrine process may contribute to the evolution of inflammatory nervous system damage in HAM/TSP.
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Affiliation(s)
- C L Tendler
- Metabolism Branche, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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Parker WB, Somers DA, Wyse DL, Keith RA, Burton JD, Gronwald JW, Gengenbach BG. Selection and characterization of sethoxydim- tolerant maize tissue cultures. Plant Physiol 1990; 92:1220-5. [PMID: 16667393 PMCID: PMC1062439 DOI: 10.1104/pp.92.4.1220] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
;Black Mexican Sweet' (BMS) maize (Zea mays L.) tissue cultures were selected for tolerance to sethoxydim. Sethoxydim, a cyclohexanedione, and haloxyfop, an aryloxyphenoxypropionate, exert herbicidal activity on most monocots including maize by inhibiting acetyl-coenzyme A carboxylase (ACCase). Selected line B10S grew on medium containing 10 micromolar sethoxydim. Lines B50S and B100S were subsequent selections from B10S that grew on medium containing 50 and 100 micromolar sethoxydim, respectively. Growth rates of BMS, B10S, B50S, and B100S were similar in the absence of herbicide. Herbicide concentrations reducing growth by 50% were 0.6, 4.5, 35, and 26 micromolar sethoxydim and 0.06, 0.5, 5.4, and 1.8 micromolar haloxyfop for BMS, B10S, B50S, and B100S, respectively. Sethoxydim and haloxyfop concentrations that inhibited ACCase by 50% were similar for BMS, B10S, B50S, and B100S. However, ACCase activities were 6.01, 10.7, 16.1, and 11.4 nmol HCO(3) (-) incorporated per milligram of protein per minute in extracts of BMS, B10S, B50S, and B100S, respectively, suggesting that increased wild-type ACCase activity conferred herbicide tolerance. Incorporation of [(14)C]acetate into the nonpolar lipid fraction was higher for B50S than for BMS in the absence of sethoxydim providing further evidence for an increase in ACCase activity in the selected line. In the presence of 5 micromolar sethoxydim, [(14)C]acetate incorporation by B50S was similar to that for untreated BMS. The levels of a biotin-containing polypeptide (about 220,000 molecular weight), presumably the ACCase subunit, were increased in the tissue cultures that exhibited elevated ACCase activity indicating overproduction of the ACCase enzyme.
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Affiliation(s)
- W B Parker
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota 55108
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Abstract
The nature of the interleukin 2 (IL-2) receptor on purified human B lymphocytes was examined. Both normal and malignant cells showed evidence of a 70-75,000 mol. wt (p75) IL-2 binding molecule as assessed by 125I-labeled IL-2 binding and receptor cross-linking. On normal, Tac-negative B lymphocytes the estimated number of p75 binding sites was 1100 per cell and the dissociation constant (Kd) was 1.7 nM. Consistent with this, cross-linking experiments demonstrated the presence of an IL-2 binding molecule of 70-75,000 mol. wt. Purified B cells from patients with hairy cell leukemia and chronic lymphocytic leukemia (CLL) also expressed the p75 IL-2 binding molecule. In the HCL samples, a small number of high-affinity IL-2 binding sites were detected (27-90) while the majority of binding sites (2100-10,800) were typical of low-affinity p55 Tac binding. IL-2 added to the purified normal and CLL B lymphocytes led to the induction of p55 Tac expression and the generation of high-affinity IL-2 receptors. This response to IL-2 was equivalent to the response observed when normal B lymphocytes were stimulated by Staphylococcus aureus Cowan I.
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Affiliation(s)
- C G Begley
- Metabolism Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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Burton JD. Disasters and mysteries at Heathrow. Med Leg J 1989; 57 ( Pt 1):6-18. [PMID: 2716697 DOI: 10.1177/002581728905700104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Abstract
To determine if the frequently observed T cell and natural killer dysfunction in B-chronic lymphocytic leukemia might be related to the presence of large numbers of malignant B cells, we studied the effects of secretory or shed products of CLL B cells on normal (control) T cell and NK function. The cell-free supernatants from CLL B cells cultured from 24 to 48 hr inhibited a variety of T cell functions including: PHA-induced proliferation, PHA-stimulated entry of T cells into the cell cycle, and PHA-induced production of interleukin-2. In addition, B-CLL supernatants diminished control NK activity. Purified control B cells and other malignant cell lines produced little or no inhibitory activity toward these T cell or NK functions. The sera from these same B-CLL patients diminished PHA-induced interleukin-2 production by control T cells. Initial molecular characterization of the inhibitory factor(s) revealed it to be of low molecular weight (less than 5000 daltons) with loss of functional activity after treatment with neuraminidase. This suggested that this substance might be either a ganglioside or glycoprotein whose inhibitory activity depends on the presence of a sialic acid moiety. If CLL B cells are capable of secreting or shedding immunosuppressive factor(s), then alteration of this property may result in a more normal immune system for these patients.
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Affiliation(s)
- J D Burton
- Department of Medicine, University of Minnesota, Minneapolis
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Burton JD, Gronwald JW, Somers DA, Connelly JA, Gengenbach BG, Wyse DL. Inhibition of plant acetyl-coenzyme A carboxylase by the herbicides sethoxydim and haloxyfop. Biochem Biophys Res Commun 1987; 148:1039-44. [PMID: 2891354 DOI: 10.1016/s0006-291x(87)80236-x] [Citation(s) in RCA: 155] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Incorporation of [14C]acetate or [14C]pyruvate into fatty acids in isolated corn seedling chloroplasts was inhibited 90% or greater by 10 microM sethoxydim or 1 microM haloxyfop. At these concentrations, neither sethoxydim nor haloxyfop inhibited [14C]acetate incorporation into fatty acids in isolated pea chloroplasts. Sethoxydim (10 microM) and haloxyfop (1 microM) did not inhibit incorporation of [14C]malonyl-CoA into fatty acids in cell free extracts from corn tissue cultures. Acetyl coenzyme A carboxylase (EC 6.4.1.2) from corn seedling chloroplasts was inhibited by both sethoxydim and haloxyfop, with I50 values of 2.9 and 0.5 microM, respectively. This enzyme in pea was not inhibited by 10 microM sethoxydim or 1 microM haloxyfop.
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Affiliation(s)
- J D Burton
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul 55108
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