1
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Lee HN, Marathe SK, Otegui MS. Chloroplast microautophagy: A green role for NBR1. Autophagy 2023; 19:3244-3245. [PMID: 37561023 PMCID: PMC10621284 DOI: 10.1080/15548627.2023.2246857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 07/25/2023] [Accepted: 07/26/2023] [Indexed: 08/11/2023] Open
Affiliation(s)
- Han Nim Lee
- Department of Botany and Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, WI, USA
| | - Sarika K. Marathe
- Department of Botany and Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, WI, USA
| | - Marisa S. Otegui
- Department of Botany and Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, WI, USA
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2
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Miao H, Zhang TT, Li HX, Fabbris G, Said AH, Tartaglia R, Yilmaz T, Vescovo E, Yin JX, Murakami S, Feng XL, Jiang K, Wu XL, Wang AF, Okamoto S, Wang YL, Lee HN. Signature of spin-phonon coupling driven charge density wave in a kagome magnet. Nat Commun 2023; 14:6183. [PMID: 37793998 PMCID: PMC10550957 DOI: 10.1038/s41467-023-41957-5] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 09/21/2023] [Indexed: 10/06/2023] Open
Abstract
The intertwining between spin, charge, and lattice degrees of freedom can give rise to unusual macroscopic quantum states, including high-temperature superconductivity and quantum anomalous Hall effects. Recently, a charge density wave (CDW) has been observed in the kagome antiferromagnet FeGe, indicative of possible intertwining physics. An outstanding question is that whether magnetic correlation is fundamental for the spontaneous spatial symmetry breaking orders. Here, utilizing elastic and high-resolution inelastic x-ray scattering, we observe a c-axis superlattice vector that coexists with the 2[Formula: see text]2[Formula: see text]1 CDW vectors in the kagome plane. Most interestingly, between the magnetic and CDW transition temperatures, the phonon dynamical structure factor shows a giant phonon-energy hardening and a substantial phonon linewidth broadening near the c-axis wavevectors, both signaling the spin-phonon coupling. By first principles and model calculations, we show that both the static spin polarization and dynamic spin excitations intertwine with the phonon to drive the spatial symmetry breaking in FeGe.
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Affiliation(s)
- H Miao
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
| | - T T Zhang
- Department of Physics, Tokyo Institute of Technology, Okayama, Meguro-ku, Tokyo, Japan
| | - H X Li
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- Advanced Materials Thrust, The Hong Kong University of Science and Technology (Guangzhou), Guangzhou, China
| | - G Fabbris
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
| | - A H Said
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
| | - R Tartaglia
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
- "Gleb Wataghin" Institute of Physics, University of Campinas, Campinas, São Paulo, Brazil
| | - T Yilmaz
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York, USA
| | - E Vescovo
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York, USA
| | - J-X Yin
- Laboratory for Quantum Emergence, Department of Physics, Southern University of Science and Technology, Shenzhen, China
| | - S Murakami
- Department of Physics, Tokyo Institute of Technology, Okayama, Meguro-ku, Tokyo, Japan
| | - X L Feng
- Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - K Jiang
- Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - X L Wu
- Low Temperature Physics Laboratory, College of Physics and Center of Quantum Materials and Devices, Chongqing University, Chongqing, China
| | - A F Wang
- Low Temperature Physics Laboratory, College of Physics and Center of Quantum Materials and Devices, Chongqing University, Chongqing, China.
| | - S Okamoto
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
| | - Y L Wang
- School of Emerging Technology, University of Science and Technology of China, Hefei, Anhui, China.
| | - H N Lee
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
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3
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Lee HN, Chacko J, Gonzalez Solís A, Chen KE, Barros JAS, Signorelli S, Millar AH, Vierstra RD, Eliceiri KW, Otegui MS. The autophagy receptor NBR1 directs the clearance of photodamaged chloroplasts. eLife 2023; 12:86030. [PMID: 37070813 PMCID: PMC10156165 DOI: 10.7554/elife.86030] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 04/17/2023] [Indexed: 04/19/2023] Open
Abstract
The ubiquitin-binding NBR1 autophagy receptor plays a prominent role in recognizing ubiquitylated protein aggregates for vacuolar degradation by macroautophagy. Here, we show that upon exposing Arabidopsis plants to intense light, NBR1 associates with photodamaged chloroplasts independently of ATG7, a core component of the canonical autophagy machinery. NBR1 coats both the surface and interior of chloroplasts, which is then followed by direct engulfment of the organelles into the central vacuole via a microautophagy-type process. The relocalization of NBR1 into chloroplasts does not require the chloroplast translocon complexes embedded in the envelope but is instead greatly enhanced by removing the self-oligomerization mPB1 domain of NBR1. The delivery of NBR1-decorated chloroplasts into vacuoles depends on the ubiquitin-binding UBA2 domain of NBR1 but is independent of the ubiquitin E3 ligases SP1 and PUB4, known to direct the ubiquitylation of chloroplast surface proteins. Compared to wild-type plants, nbr1 mutants have altered levels of a subset of chloroplast proteins and display abnormal chloroplast density and sizes upon high light exposure. We postulate that, as photodamaged chloroplasts lose envelope integrity, cytosolic ligases reach the chloroplast interior to ubiquitylate thylakoid and stroma proteins which are then recognized by NBR1 for autophagic clearance. This study uncovers a new function of NBR1 in the degradation of damaged chloroplasts by microautophagy.
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Affiliation(s)
- Han Nim Lee
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, United States
| | - Jenu Chacko
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, United States
| | - Ariadna Gonzalez Solís
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, United States
| | - Kuo-En Chen
- Department of Biology, Washington University in St. Louis, Saint Louis, United States
| | - Jessica A S Barros
- Department of Biology, Washington University in St. Louis, Saint Louis, United States
| | - Santiago Signorelli
- Department of Plant Biology, Universidad de la República, Montevideo, Uruguay
| | - A Harvey Millar
- School of Molecular Sciences, University of Western Australia, Perth, Australia
| | | | - Kevin W Eliceiri
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, United States
| | - Marisa S Otegui
- Department of Botany, University of Wisconsin-Madison, Madison, United States
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4
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Zhong Y, Li S, Liu H, Dong Y, Aido K, Arai Y, Li H, Zhang W, Shi Y, Wang Z, Shin S, Lee HN, Miao H, Kondo T, Okazaki K. Testing electron-phonon coupling for the superconductivity in kagome metal CsV 3Sb 5. Nat Commun 2023; 14:1945. [PMID: 37029104 PMCID: PMC10082024 DOI: 10.1038/s41467-023-37605-7] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 03/23/2023] [Indexed: 04/09/2023] Open
Abstract
In crystalline materials, electron-phonon coupling (EPC) is a ubiquitous many-body interaction that drives conventional Bardeen-Cooper-Schrieffer superconductivity. Recently, in a new kagome metal CsV3Sb5, superconductivity that possibly intertwines with time-reversal and spatial symmetry-breaking orders is observed. Density functional theory calculations predicted weak EPC strength, λ, supporting an unconventional pairing mechanism in CsV3Sb5. However, experimental determination of λ is still missing, hindering a microscopic understanding of the intertwined ground state of CsV3Sb5. Here, using 7-eV laser-based angle-resolved photoemission spectroscopy and Eliashberg function analysis, we determine an intermediate λ=0.45-0.6 at T = 6 K for both Sb 5p and V 3d electronic bands, which can support a conventional superconducting transition temperature on the same magnitude of experimental value in CsV3Sb5. Remarkably, the EPC on the V 3d-band enhances to λ~0.75 as the superconducting transition temperature elevated to 4.4 K in Cs(V0.93Nb0.07)3Sb5. Our results provide an important clue to understand the pairing mechanism in the kagome superconductor CsV3Sb5.
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Affiliation(s)
- Yigui Zhong
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Shaozhi Li
- Material Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Hongxiong Liu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
| | - Yuyang Dong
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Kohei Aido
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Yosuke Arai
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Haoxiang Li
- Material Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
- Advanced Materials Thrust, The Hong Kong University of Science and Technology (Guangzhou), 511453, Guangzhou, Guangdong, China
| | - Weilu Zhang
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- Department of Engineering and Applied Sciences, Sophia University, Tokyo, 102-8554, Japan
| | - Youguo Shi
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China
| | - Ziqiang Wang
- Department of Physics, Boston College, Chestnut Hill, MA, 02467, USA
| | - Shik Shin
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- Office of University Professor, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - H N Lee
- Material Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - H Miao
- Material Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Takeshi Kondo
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan.
- Trans-scale Quantum Science Institute, The University of Tokyo, Bunkyo, Tokyo, 113-0033, Japan.
| | - Kozo Okazaki
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan.
- Trans-scale Quantum Science Institute, The University of Tokyo, Bunkyo, Tokyo, 113-0033, Japan.
- Material Innovation Research Center, The University of Tokyo, Kashiwa, Chiba, 277-8561, Japan.
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Kim JH, Jung H, Song K, Lee HN, Chung T. The phosphatidylinositol 3-phosphate effector FYVE3 regulates FYVE2-dependent autophagy in Arabidopsis thaliana. Front Plant Sci 2023; 14:1160162. [PMID: 37008475 PMCID: PMC10050702 DOI: 10.3389/fpls.2023.1160162] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 02/28/2023] [Indexed: 06/19/2023]
Abstract
Phosphatidylinositol 3-phosphate (PI3P) is a signaling phospholipid that play a key role in endomembrane trafficking, specifically autophagy and endosomal trafficking. However, the mechanisms underlying the contribution of PI3P downstream effectors to plant autophagy remain unknown. Known PI3P effectors for autophagy in Arabidopsis thaliana include ATG18A (Autophagy-related 18A) and FYVE2 (Fab1p, YOTB, Vac1p, and EEA1 2), which are implicated in autophagosome biogenesis. Here, we report that FYVE3, a paralog of plant-specific FYVE2, plays a role in FYVE2-dependent autophagy. Using yeast two-hybrid and bimolecular fluorescence complementation assays, we determined that the FYVE3 protein was associated with autophagic machinery containing ATG18A and FYVE2, by interacting with ATG8 isoforms. The FYVE3 protein was transported to the vacuole, and the vacuolar delivery of FYVE3 relies on PI3P biosynthesis and the canonical autophagic machinery. Whereas the fyve3 mutation alone barely affects autophagic flux, it suppresses defective autophagy in fyve2 mutants. Based on the molecular genetics and cell biological data, we propose that FYVE3 specifically regulates FYVE2-dependent autophagy.
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6
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Kim JH, Lee HN, Huang X, Jung H, Otegui MS, Li F, Chung T. FYVE2, a phosphatidylinositol 3-phosphate effector, interacts with the COPII machinery to control autophagosome formation in Arabidopsis. Plant Cell 2022; 34:351-373. [PMID: 34718777 PMCID: PMC8846182 DOI: 10.1093/plcell/koab263] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
Autophagy is an intracellular trafficking mechanism by which cytosolic macromolecules and organelles are sequestered into autophagosomes for degradation inside the vacuole. In various eukaryotes including yeast, metazoans, and plants, the precursor of the autophagosome, termed the phagophore, nucleates in the vicinity of the endoplasmic reticulum (ER) with the participation of phosphatidylinositol 3-phosphate (PI3P) and the coat protein complex II (COPII). Here we show that Arabidopsis thaliana FYVE2, a plant-specific PI3P-binding protein, provides a functional link between the COPII machinery and autophagy. FYVE2 interacts with the small GTPase Secretion-associated Ras-related GTPase 1 (SAR1), which is essential for the budding of COPII vesicles. FYVE2 also interacts with ATG18A, another PI3P effector on the phagophore membrane. Fluorescently tagged FYVE2 localized to autophagic membranes near the ER and was delivered to vacuoles. SAR1 fusion proteins were also targeted to the vacuole via FYVE2-dependent autophagy. Either mutations in FYVE2 or the expression of dominant-negative mutant SAR1B proteins resulted in reduced autophagic flux and the accumulation of autophagic organelles. We propose that FYVE2 regulates autophagosome biogenesis through its interaction with ATG18A and the COPII machinery, acting downstream of ATG2.
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Affiliation(s)
- Jeong Hun Kim
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
| | - Han Nim Lee
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
- Department of Botany and Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Xiao Huang
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Hyera Jung
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
| | - Marisa S Otegui
- Department of Botany and Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Faqiang Li
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, P. R. China
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou 510642, P. R. China
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Taijoon Chung
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
- Institute of Systems Biology, Pusan National University, Busan 46241, Republic of Korea
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7
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Lee HN, Subrayan V. I think I have double vision? Or not? Internuclear Ophthalmoplegia following right lacunar infarct. Med J Malaysia 2021; 76:950-952. [PMID: 34806694] [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] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Internuclear Ophthalmoplegia (INO) is an inability of the ipsilateral adduction with a contralateral horizontal abducting saccade on attempted gaze to the contra-lesion side. Injury to the medial longitudinal fasciculus (MLF) will obstruct the signalling pathway between the ipsilateral abducens nucleus and the contralateral medial rectus muscle. Infarction accounts for 38% of INO cases with mostly being unilateral (87%), followed by demyelination (34%), which mostly being bilateral (73%). Lacunar infarct is the most common ischemic stroke. INO can be easily missed due to its subtle presentation with no complaints from the patients. A full cranial nerves assessment, includes the extraocular muscles movement, is important. Ischemic and demyelinating INO typically recover. We present here of a case of INO following right lacunar infarct in a 72-year-old Malay woman. She had hypertensive crisis due to missed medications. Her blood pressure was well controlled throughout the hospital admission and finally she was discharged home with continuation of care at her primary facility.
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Affiliation(s)
- H N Lee
- Sultanah Fatimah Specialist Hopsital, Johor, Malaysia.
| | - V Subrayan
- University Malaya Medical Center, Kuala Lumpur, Malaysia
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8
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Goodman K, Paez-Valencia J, Pennington J, Sonntag A, Ding X, Lee HN, Ahlquist PG, Molina I, Otegui MS. ESCRT components ISTL1 andLIP5 are required for tapetal function and pollen viability. Plant Cell 2021; 33:2850-2868. [PMID: 34125207 PMCID: PMC8408459 DOI: 10.1093/plcell/koab132] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 05/07/2021] [Indexed: 05/03/2023]
Abstract
Pollen wall assembly is crucial for pollen development and plant fertility. The durable biopolymer sporopollenin and the constituents of the tryphine coat are delivered to developing pollen grains by the highly coordinated secretory activity of the surrounding tapetal cells. The role of membrane trafficking in this process, however, is largely unknown. In this study, we used Arabidopsis thaliana to characterize the role of two late-acting endosomal sorting complex required for transport (ESCRT) components, ISTL1 and LIP5, in tapetal function. Plants lacking ISTL1 and LIP5 form pollen with aberrant exine patterns, leading to partial pollen lethality. We found that ISTL1 and LIP5 are required for exocytosis of plasma membrane and secreted proteins in the tapetal cells at the free microspore stage, contributing to pollen wall development and tryphine deposition. Whereas the ESCRT machinery is well known for its role in endosomal trafficking, the function of ISTL1 and LIP5 in exocytosis is not a typical ESCRT function. The istl1 lip5 double mutants also show reduced intralumenal vesicle concatenation in multivesicular endosomes in both tapetal cells and developing pollen grains as well as morphological defects in early endosomes/trans-Golgi networks, suggesting that late ESCRT components function in the early endosomal pathway and exocytosis.
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Affiliation(s)
- Kaija Goodman
- Department of Botany, University of Wisconsin-Madison, Wisconsin 53706, USA
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Julio Paez-Valencia
- Department of Botany, University of Wisconsin-Madison, Wisconsin 53706, USA
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Janice Pennington
- Department of Botany, University of Wisconsin-Madison, Wisconsin 53706, USA
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Annika Sonntag
- Department of Biology, Algoma University, Ontario P6A 2G4, Canada
| | - Xinxin Ding
- Department of Botany, University of Wisconsin-Madison, Wisconsin 53706, USA
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Han Nim Lee
- Department of Botany, University of Wisconsin-Madison, Wisconsin 53706, USA
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Paul G. Ahlquist
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
- Department of Oncology and Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
- Morgridge Institute for Research, Madison, Wisconsin 53706, USA
| | - Isabel Molina
- Department of Biology, Algoma University, Ontario P6A 2G4, Canada
| | - Marisa S. Otegui
- Department of Botany, University of Wisconsin-Madison, Wisconsin 53706, USA
- Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
- Author for Correspondence:
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9
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Li H, Zhang TT, Said A, Fabbris G, Mazzone DG, Yan JQ, Mandrus D, Halász GB, Okamoto S, Murakami S, Dean MPM, Lee HN, Miao H. Giant phonon anomalies in the proximate Kitaev quantum spin liquid α-RuCl 3. Nat Commun 2021; 12:3513. [PMID: 34112804 PMCID: PMC8192767 DOI: 10.1038/s41467-021-23826-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 04/30/2021] [Indexed: 11/18/2022] Open
Abstract
The Kitaev quantum spin liquid epitomizes an entangled topological state, for which two flavors of fractionalized low-energy excitations are predicted: the itinerant Majorana fermion and the Z2 gauge flux. It was proposed recently that fingerprints of fractional excitations are encoded in the phonon spectra of Kitaev quantum spin liquids through a novel fractional-excitation-phonon coupling. Here, we detect anomalous phonon effects in α-RuCl3 using inelastic X-ray scattering with meV resolution. At high temperature, we discover interlaced optical phonons intercepting a transverse acoustic phonon between 3 and 7 meV. Upon decreasing temperature, the optical phonons display a large intensity enhancement near the Kitaev energy, JK~8 meV, that coincides with a giant acoustic phonon softening near the Z2 gauge flux energy scale. These phonon anomalies signify the coupling of phonon and Kitaev magnetic excitations in α-RuCl3 and demonstrates a proof-of-principle method to detect anomalous excitations in topological quantum materials.
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Affiliation(s)
- Haoxiang Li
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - T T Zhang
- Department of Physics, Tokyo Institute of Technology, Okayama, Meguro-ku, Tokyo, Japan
- Tokodai Institute for Element Strategy, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama, Kanagawa, Japan
| | - A Said
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
| | - G Fabbris
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
| | - D G Mazzone
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, Villigen, Switzerland
| | - J Q Yan
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - D Mandrus
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- Department of Materials Science and Engineering, the University of Tennessee at Knoxville, Knoxville, TN, USA
| | - Gábor B Halász
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - S Okamoto
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - S Murakami
- Department of Physics, Tokyo Institute of Technology, Okayama, Meguro-ku, Tokyo, Japan
- Tokodai Institute for Element Strategy, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama, Kanagawa, Japan
| | - M P M Dean
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - H N Lee
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - H Miao
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
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10
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Chacko JV, Lee HN, Wu W, Otegui MS, Eliceiri KW. Hyperdimensional Imaging Contrast Using an Optical Fiber. Sensors (Basel) 2021; 21:s21041201. [PMID: 33572130 PMCID: PMC7914562 DOI: 10.3390/s21041201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/01/2021] [Accepted: 02/05/2021] [Indexed: 11/16/2022]
Abstract
Fluorescence properties of a molecule can be used to study the structural and functional nature of biological processes. Physical properties, including fluorescence lifetime, emission spectrum, emission polarization, and others, help researchers probe a molecule, produce desired effects, and infer causes and consequences. Correlative imaging techniques such as hyperdimensional imaging microscopy (HDIM) combine the physical properties and biochemical states of a fluorophore. Here we present a fiber-based imaging system that can generate hyper-dimensional contrast by combining multiple fluorescence properties into a single fluorescence lifetime decay curve. Fluorescence lifetime imaging microscopy (FLIM) with controlled excitation polarization and temporally dispersed emission can generate a spectrally coded, polarization-filtered lifetime distribution for a pixel. This HDIM scheme generates a better contrast between different molecules than that from individual techniques. This setup uses only a single detector and is simpler to implement, modular, cost-efficient, and adaptable to any existing FLIM microscope. We present higher contrast data from Arabidopsis thaliana epidermal cells based on intrinsic anthocyanin emission properties under multiphoton excitation. This work lays the foundation for an alternative hyperdimensional imaging system and demonstrates that contrast-based imaging is useful to study cellular heterogeneity in biological samples.
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Affiliation(s)
- Jenu V. Chacko
- Center for Quantitative Cell Imaging, University of Wisconsin, Madison, WI 53706, USA; (J.V.C.); (H.N.L.); (W.W.); (M.S.O.)
| | - Han Nim Lee
- Center for Quantitative Cell Imaging, University of Wisconsin, Madison, WI 53706, USA; (J.V.C.); (H.N.L.); (W.W.); (M.S.O.)
- Department of Botany, University of Wisconsin, Madison, WI, 53706, USA
| | - Wenxin Wu
- Center for Quantitative Cell Imaging, University of Wisconsin, Madison, WI 53706, USA; (J.V.C.); (H.N.L.); (W.W.); (M.S.O.)
| | - Marisa S. Otegui
- Center for Quantitative Cell Imaging, University of Wisconsin, Madison, WI 53706, USA; (J.V.C.); (H.N.L.); (W.W.); (M.S.O.)
- Department of Botany, University of Wisconsin, Madison, WI, 53706, USA
| | - Kevin W. Eliceiri
- Center for Quantitative Cell Imaging, University of Wisconsin, Madison, WI 53706, USA; (J.V.C.); (H.N.L.); (W.W.); (M.S.O.)
- Department of Biomedical Engineering, University of Wisconsin, Madison, WI 53706, USA
- Department of Medical Physics, University of Wisconsin, Madison, WI 53706, USA
- Morgridge Institute for Research, University of Wisconsin, Madison, WI 53706, USA
- Correspondence:
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Jung H, Lee HN, Marshall RS, Lomax AW, Yoon MJ, Kim J, Kim JH, Vierstra RD, Chung T. Arabidopsis cargo receptor NBR1 mediates selective autophagy of defective proteins. J Exp Bot 2020; 71:73-89. [PMID: 31494674 PMCID: PMC6913707 DOI: 10.1093/jxb/erz404] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Accepted: 08/30/2019] [Indexed: 05/04/2023]
Abstract
Aggrephagy, a type of selective autophagy that sequesters protein aggregates for degradation in the vacuole, is an important protein quality control mechanism, particularly during cell stress. In mammalian cells, aggrephagy and several other forms of selective autophagy are mediated by dedicated cargo receptors such as NEIGHBOR OF BRCA1 (NBR1). Although plant NBR1 homologs have been linked to selective autophagy during biotic stress, it remains unclear how they impact selective autophagy under non-stressed and abiotic stress conditions. Through microscopic and biochemical analysis of nbr1 mutants expressing autophagy markers and an aggregation-prone reporter, we tested the connection between NBR1 and aggrephagy in Arabidopsis. Although NBR1 is not essential for general autophagy, or for the selective clearance of peroxisomes, mitochondria, or the ER, we found that NBR1 is required for the heat-induced formation of autophagic vesicles. Moreover, cytoplasmic puncta containing aggregation-prone proteins, which were rarely observed in wild-type plants, were found to accumulate in nbr1 mutants under both control and heat stress conditions. Given that NBR1 co-localizes with these cytoplasmic puncta, we propose that Arabidopsis NBR1 is a plant aggrephagy receptor essential for maintaining proteostasis under both heat stress and non-stress conditions.
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Affiliation(s)
- Hyera Jung
- Department of Biological Sciences, Pusan National University, Busan, Republic of Korea
| | - Han Nim Lee
- Department of Biological Sciences, Pusan National University, Busan, Republic of Korea
- Present address: Department of Botany and Laboratory of Cell and Molecular Biology, University of Wisconsin, Madison, WI 53706, USA
| | - Richard S Marshall
- Department of Biology, Washington University in St Louis, St Louis, MO USA
| | - Aaron W Lomax
- Department of Genetics, University of Wisconsin, Madison, WI, USA
- Present address: Department of Soil Science, University of Wisconsin, Madison, WI 53706, USA
| | - Min Ji Yoon
- Department of Biological Sciences, Pusan National University, Busan, Republic of Korea
- Present address: Department of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Jimi Kim
- Department of Biological Sciences, Pusan National University, Busan, Republic of Korea
| | - Jeong Hun Kim
- Department of Biological Sciences, Pusan National University, Busan, Republic of Korea
| | - Richard D Vierstra
- Department of Biology, Washington University in St Louis, St Louis, MO USA
- Department of Genetics, University of Wisconsin, Madison, WI, USA
- Correspondence: or
| | - Taijoon Chung
- Department of Biological Sciences, Pusan National University, Busan, Republic of Korea
- Correspondence: or
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12
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Park IY, Kim MR, Lee HN, Gen Y, Kim MJ. Risk factors for Korean women to develop an isthmocele after a cesarean section. BMC Pregnancy Childbirth 2018; 18:162. [PMID: 29764452 PMCID: PMC5952596 DOI: 10.1186/s12884-018-1821-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 05/02/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The increase in number of cesarean section (CS) operations has resulted in an increase in cases of isthmocele development. The objective of this study is to determine the risk factors for isthmocele development after CS. METHODS Isthmocele measurements were taken for 404 women with a history of at least one low transverse CS. The following potential risk factors were investigated: patient's age at CS, cause of CS, weeks of gestation at CS, premature rupture of membrane (PROM), phase of labor, type suture (single/double layer), operation time, uterine flexion (anteversion/retroversion), and blood transfusion during operation. A transvaginal ultrasound was carried out to examine the isthmocele in the uterus after CS, including the shape of the isthmocele, residual myometrial thickness, depth and width of isthmocele, cervical thickness, location of the isthmocele, and clinical characteristics. RESULTS In our study population, the isthmocele had a prevalence of 73.8%. Most isthmocele had a triangular (65.4%) or semicircular shape (10.4%). The presence of an isthmocele was significantly associated with repeat CS, premature rupture of membrane (PROM), short operation time, and extent of cervix dilatation at CS. The risk of isthmocele was low in women who had placenta previa totalis (PPT), twin, a long operation time, or a transfusion during the operation. CONCLUSIONS In our study, isthmocele development was significantly associated with repeat CS, PROM, a short operation time, and the extent of cervix dilatation at CS. Therefore, PROM prevention and a more careful uterine closure are needed to reduce the risk of developing an isthmocele after CS.
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Affiliation(s)
- I Y Park
- Department of Obstetrics and Gynecology, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Republic of Korea
| | - M R Kim
- Department of Obstetrics and Gynecology, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Republic of Korea
| | - H N Lee
- Department of Obstetrics and Gynecology, College of Medicine, Bucheon St. Mary's Hospital, The Catholic University of Korea, 327 Sosa-ro, Bucheon, Gyeonggi-do, 14647, Republic of Korea
| | - Y Gen
- Department of Obstetrics and Gynecology, College of Medicine, Bucheon St. Mary's Hospital, The Catholic University of Korea, 327 Sosa-ro, Bucheon, Gyeonggi-do, 14647, Republic of Korea
| | - M J Kim
- Department of Obstetrics and Gynecology, College of Medicine, Bucheon St. Mary's Hospital, The Catholic University of Korea, 327 Sosa-ro, Bucheon, Gyeonggi-do, 14647, Republic of Korea.
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13
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Woo OG, Kim SH, Cho SK, Kim SH, Lee HN, Chung T, Yang SW, Lee JH. BPH1, a novel substrate receptor of CRL3, plays a repressive role in ABA signal transduction. Plant Mol Biol 2018; 96:593-606. [PMID: 29560577 DOI: 10.1007/s11103-018-0717-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [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: 08/17/2017] [Accepted: 03/06/2018] [Indexed: 06/08/2023]
Abstract
BPH1 acts as a substrate receptor of CRL3 complex and negatively regulates ABA-mediated cellular responses. The study on its function provides information that helps further understand the relationship between ABA signaling and UPS. Abscisic acid (ABA) plays a crucial role in a variety of cellular processes, including seed dormancy, inhibition of seedling growth, and drought resistance in plants. Cullin3-RING E3 ligase (CRL3) complex is a type of multi-subunit E3 ligase, and BTB/POZ protein, a component of CRL3 complex, functions as a receptor to determine a specific substrate. To elucidate the CRL3 complex that participates in ABA-mediated cellular processes, we first investigated ABA-inducible BTB/POZ genes based on data from the AtGenExpress Visualization Tool (AVT). We then isolated an ABA-inducible gene encoding a potential CRL3 substrate receptor in Arabidopsis, BPH1 (BTB/POZ protein hypersensitive to ABA 1). The isolate gene has a BTB/POZ domain and a NPH3 domain within its N-terminal and C-terminal region, respectively. Yeast two-hybrid and co-immunoprecipitation assays showed that BPH1 physically interacted with cullin3a, a scaffold protein of CRL3, suggesting that it functions as an Arabidopsis CRL3 substrate receptor. The functional mutation of BPH1 caused delayed seed germination in response to ABA and enhanced sensitivity by NaCl and mannitol treatments as ABA-related stresses. Moreover, bph1 mutants exhibited enhanced stomatal closure under ABA application and reduced water loss when compared with wild-type, implying their enhanced tolerance to drought stress. Based on the information from microarray/AVT data and expression analysis of various ABA-inducible genes between wild-type and bph1 plants following ABA treatments, we concluded loss of BPH1 resulted in hyper-induction of a large portion of ABA-inducible genes in response to ABA. Taken together, these results show that BPH1 is negatively involved in ABA-mediated cellular events.
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Affiliation(s)
- Og-Geum Woo
- Department of Biology Education, Pusan National University, Busan, 46241, South Korea
- Department of Integrated Biological Science, Pusan National University, Busan, 46241, South Korea
| | - Soon-Hee Kim
- Department of Biology Education, Pusan National University, Busan, 46241, South Korea
| | - Seok Keun Cho
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, South Korea
| | - Sang-Hoon Kim
- Department of Biology Education, Pusan National University, Busan, 46241, South Korea
| | - Han Nim Lee
- Department of Biological Sciences, Pusan National University, Busan, 46241, South Korea
| | - Taijoon Chung
- Department of Biological Sciences, Pusan National University, Busan, 46241, South Korea
| | - Seong Wook Yang
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, South Korea
- Section of Plant Biochemistry, Department of Plant and Environmental Sciences, Faculty of Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark
| | - Jae-Hoon Lee
- Department of Biology Education, Pusan National University, Busan, 46241, South Korea.
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Lee HN, Zarza X, Kim JH, Yoon MJ, Kim SH, Lee JH, Paris N, Munnik T, Otegui MS, Chung T. Vacuolar Trafficking Protein VPS38 Is Dispensable for Autophagy. Plant Physiol 2018; 176:1559-1572. [PMID: 29184027 PMCID: PMC5813560 DOI: 10.1104/pp.17.01297] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 11/27/2017] [Indexed: 05/18/2023]
Abstract
Phosphatidylinositol 3-P (PI3P) is a signaling molecule that controls a variety of processes in endosomal, autophagic, and vacuolar/lysosomal trafficking in yeasts and mammals. Vacuolar protein sorting 34 (Vps34) is a conserved PI3K present in multiple complexes with specific functions and regulation. In yeast, the PI3K complex II consists of Vps34p, Vps15p, Vps30p/Atg6p, and Vps38p, and is essential for vacuolar protein sorting. Here, we describe the Arabidopsis (Arabidopsis thaliana) homolog of yeast Vps38p and human UV radiation resistance-associated gene protein. Arabidopsis VPS38 interacts with VPS30/ATG6 both in yeast and in planta. Although the level of PI3P in Arabidopsis vps38 mutants is similar to that in wild type, vps38 cells contain enlarged multivesicular endosomes and fewer organelles enriched in PI3P than the wild type. The vps38 mutants are defective in the trafficking of vacuolar cargo and its receptor VACUOLAR SORTING RECEPTOR2;1. The mutants also exhibit abnormal cytoplasmic distributions of endocytic cargo, such as auxin efflux carriers PINFORMED1 (PIN1) and PIN2. Constitutive autophagy is normal in the mutants but starvation-induced autophagy was slightly inhibited. We conclude that Arabidopsis VPS38 is dispensable for autophagy but essential for efficient targeting of biosynthetic and endocytic cargo to the vacuole.
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Affiliation(s)
- Han Nim Lee
- Department of Biological Sciences, Pusan National University, Busan 46241, Korea
| | - Xavier Zarza
- Swammerdam Institute for Life Sciences, Section Plant Cell Biology, University of Amsterdam, 1098 XH Amsterdam, The Netherlands
| | - Jeong Hun Kim
- Department of Biological Sciences, Pusan National University, Busan 46241, Korea
| | - Min Ji Yoon
- Department of Biological Sciences, Pusan National University, Busan 46241, Korea
| | - Sang-Hoon Kim
- Department of Biology Education, Pusan National University, Busan 46241, Korea
| | - Jae-Hoon Lee
- Department of Biology Education, Pusan National University, Busan 46241, Korea
| | - Nadine Paris
- Biochimie et Physiologie Moléculaire des Plantes, Institute Biologie Intégrative des Plantes, UMR 5004 CNRS/UMR 0386 INRA/Montpellier SupAgro/Université Montpellier 2, F-34060 Montpellier Cedex 1, France
| | - Teun Munnik
- Swammerdam Institute for Life Sciences, Section Plant Cell Biology, University of Amsterdam, 1098 XH Amsterdam, The Netherlands
| | - Marisa S Otegui
- Laboratory of Cell and Molecular Biology and Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Taijoon Chung
- Department of Biological Sciences, Pusan National University, Busan 46241, Korea
- Institute of Systems Biology, Pusan National University, Busan 46241, Korea
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15
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Lee JH, Choi WS, Jeen H, Lee HJ, Seo JH, Nam J, Yeom MS, Lee HN. Strongly Coupled Magnetic and Electronic Transitions in Multivalent Strontium Cobaltites. Sci Rep 2017; 7:16066. [PMID: 29167490 PMCID: PMC5700177 DOI: 10.1038/s41598-017-16246-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 10/13/2017] [Indexed: 12/21/2022] Open
Abstract
The topotactic phase transition in SrCoOx (x = 2.5–3.0) makes it possible to reversibly transit between the two distinct phases, i.e. the brownmillerite SrCoO2.5 that is a room-temperature antiferromagnetic insulator (AFM-I) and the perovskite SrCoO3 that is a ferromagnetic metal (FM-M), owing to their multiple valence states. For the intermediate x values, the two distinct phases are expected to strongly compete with each other. With oxidation of SrCoO2.5, however, it has been conjectured that the magnetic transition is decoupled to the electronic phase transition, i.e., the AFM-to-FM transition occurs before the insulator-to-metal transition (IMT), which is still controversial. Here, we bridge the gap between the two-phase transitions by density-functional theory calculations combined with optical spectroscopy. We confirm that the IMT actually occurs concomitantly with the FM transition near the oxygen content x = 2.75. Strong charge-spin coupling drives the concurrent IMT and AFM-to-FM transition, which fosters the near room-T magnetic transition characteristic. Ultimately, our study demonstrates that SrCoOx is an intriguingly rare candidate for inducing coupled magnetic and electronic transition via fast and reversible redox reactions.
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Affiliation(s)
- J H Lee
- School of Energy and Chemical Engineering, Ulsan National Institute of Science & Technology (UNIST), Ulsan, 44919, Republic of Korea.
| | - Woo Seok Choi
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.,Department of Physics, Sungkyunkwan University, Suwon, 440-746, Korea
| | - H Jeen
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.,Department of Physics, Pusan National University, Busan, 46241, Korea
| | - H-J Lee
- School of Energy and Chemical Engineering, Ulsan National Institute of Science & Technology (UNIST), Ulsan, 44919, Republic of Korea
| | - J H Seo
- School of Energy and Chemical Engineering, Ulsan National Institute of Science & Technology (UNIST), Ulsan, 44919, Republic of Korea
| | - J Nam
- School of Energy and Chemical Engineering, Ulsan National Institute of Science & Technology (UNIST), Ulsan, 44919, Republic of Korea
| | - M S Yeom
- Department of Applied Research and Network R&D, Center for Computational Science and Engineering, Division of National Supercomputing R&D, Korea Institute of Science and Technology Information (KISTI), 245 Daehak-ro, Daejeon, 34141, Republic of Korea.
| | - H N Lee
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
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16
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Halvorsen EC, Hamilton MJ, Young A, Wadsworth BJ, LePard NE, Lee HN, Firmino N, Collier JL, Bennewith KL. Maraviroc decreases CCL8-mediated migration of CCR5(+) regulatory T cells and reduces metastatic tumor growth in the lungs. Oncoimmunology 2016; 5:e1150398. [PMID: 27471618 DOI: 10.1080/2162402x.2016.1150398] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 01/21/2016] [Accepted: 01/31/2016] [Indexed: 02/08/2023] Open
Abstract
Regulatory T cells (Tregs) play a crucial physiological role in the regulation of immune homeostasis, although recent data suggest Tregs can contribute to primary tumor growth by suppressing antitumor immune responses. Tregs may also influence the development of tumor metastases, although there is a paucity of information regarding the phenotype and function of Tregs in metastatic target organs. Herein, we demonstrate that orthotopically implanted metastatic mammary tumors induce significant Treg accumulation in the lungs, which is a site of mammary tumor metastasis. Tregs in the primary tumor and metastatic lungs express high levels of C-C chemokine receptor type 5 (CCR5) relative to Tregs in the mammary fat pad and lungs of tumor-free mice, and Tregs in the metastatic lungs are enriched for CCR5 expression in comparison to other immune cell populations. We also identify that C-C chemokine ligand 8 (CCL8), an endogenous ligand of CCR5, is produced by F4/80(+) macrophages in the lungs of mice with metastatic primary tumors. Migration of Tregs toward CCL8 ex vivo is reduced in the presence of the CCR5 inhibitor Maraviroc. Importantly, treatment of mice with Maraviroc (MVC) reduces the level of CCR5(+) Tregs and metastatic tumor burden in the lungs. This work provides evidence of a CCL8/CCR5 signaling axis driving Treg recruitment to the lungs of mice bearing metastatic primary tumors, representing a potential therapeutic target to decrease Treg accumulation and metastatic tumor growth.
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Affiliation(s)
- E C Halvorsen
- Integrative Oncology Department, British Columbia Cancer Agency, Vancouver, BC, Canada; Interdisciplinary Oncology Program, University of British Columbia, Vancouver, BC, Canada
| | - M J Hamilton
- Integrative Oncology Department, British Columbia Cancer Agency , Vancouver, BC, Canada
| | - A Young
- Integrative Oncology Department, British Columbia Cancer Agency, Vancouver, BC, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - B J Wadsworth
- Integrative Oncology Department, British Columbia Cancer Agency, Vancouver, BC, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - N E LePard
- Integrative Oncology Department, British Columbia Cancer Agency , Vancouver, BC, Canada
| | - H N Lee
- Integrative Oncology Department, British Columbia Cancer Agency , Vancouver, BC, Canada
| | - N Firmino
- Integrative Oncology Department, British Columbia Cancer Agency, Vancouver, BC, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - J L Collier
- Integrative Oncology Department, British Columbia Cancer Agency, Vancouver, BC, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - K L Bennewith
- Integrative Oncology Department, British Columbia Cancer Agency, Vancouver, BC, Canada; Interdisciplinary Oncology Program, University of British Columbia, Vancouver, BC, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
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17
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Liu ZQ, Li L, Gai Z, Clarkson JD, Hsu SL, Wong AT, Fan LS, Lin MW, Rouleau CM, Ward TZ, Lee HN, Sefat AS, Christen HM, Ramesh R. Full Electroresistance Modulation in a Mixed-Phase Metallic Alloy. Phys Rev Lett 2016; 116:097203. [PMID: 26991197 DOI: 10.1103/physrevlett.116.097203] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Indexed: 06/05/2023]
Abstract
We report a giant, ∼22%, electroresistance modulation for a metallic alloy above room temperature. It is achieved by a small electric field of 2 kV/cm via piezoelectric strain-mediated magnetoelectric coupling and the resulting magnetic phase transition in epitaxial FeRh/BaTiO_{3} heterostructures. This work presents detailed experimental evidence for an isothermal magnetic phase transition driven by tetragonality modulation in FeRh thin films, which is in contrast to the large volume expansion in the conventional temperature-driven magnetic phase transition in FeRh. Moreover, all the experimental results in this work illustrate FeRh as a mixed-phase model system well similar to phase-separated colossal magnetoresistance systems with phase instability therein.
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Affiliation(s)
- Z Q Liu
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA
| | - L Li
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Z Gai
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J D Clarkson
- Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA
| | - S L Hsu
- Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA
| | - A T Wong
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - L S Fan
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - M-W Lin
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - C M Rouleau
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - T Z Ward
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - H N Lee
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A S Sefat
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - H M Christen
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - R Ramesh
- Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA
- Department of Physics, University of California, Berkeley, California 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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18
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Choi JI, Lee HJ, Shin YJ, Lim HW, Lee HN. Rapid enlargement of endometrial stromal sarcoma after uterine fibroid embolization for presumed adenomyosis: a case report and literature review. EUR J GYNAECOL ONCOL 2016; 37:876-881. [PMID: 29943942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Uterine sarcomas have rarely been diagnosed after uterine artery embolization. It remains unclear whether the diagnostic work-up is required prior to such embolization to prevent a missed diagnosis of sarcomas and a delay in providing definitive treatment. Because of the rarity and heterogeneity of endometrial stromal neoplasms, little is known about their epidemiology, pathogenesis, and molecular pathology. The authors report a case of low-grade endometrial stromal sarcoma (ESS) diagnosed after uterine fibroid embolization. Although they performed laparoscopic biopsy of the rapidly growing uterine mass, they could not detect the ESS. Although rare, ESS should be considered in the differential diagnosis of uterine fibroid enlargement. It is essential to assess the risk of malignancy by taking into account the patient's clinical symptoms, results of the physical exam, and imaging findings prior to uterine artery embolization. Pathologic diagnosis should include an adequate biopsy sample and the use of molecular genetic testing.
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Lee DW, Lee HN. Hysteroscopic Vaginal Septum Resection in Adolescent Girl With Herlyn-Werner-Wunderlich Syndrome. J Minim Invasive Gynecol 2015; 22:S191. [DOI: 10.1016/j.jmig.2015.08.698] [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: 11/16/2022]
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Sung HH, Han DH, Kim TH, Lee YS, Lee HN, Seo JT, Choo MS, Lee KS. Interventions do not enhance medication persistence and compliance in patients with overactive bladder: a 24 weeks, randomised, open-label, multi-center trial. Int J Clin Pract 2015. [PMID: 26215431 DOI: 10.1111/ijcp.12705] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVES Anticholinergics are currently the mainstay for the management of overactive bladder (OAB). However, low drug adherence has been noted with these medications. The aim of this study was to determine whether a health education intervention (HEI) could improve drug persistence with anticholinergics in OAB patients. METHODS We enrolled 682 OAB patients who were randomly distributed into either the HEI plus fesoterodine (HEI) group or the fesoterodine alone (control) group. The HEI consists of four education sections: understanding OAB disease, dietary control, bladder training and understanding anticholinergics. The primary end-point was the difference in drug persistence between the HEI and control groups at 24 weeks. Persistence was defined as a gap ≤ 30 days between successive prescription pills. RESULTS Among the 682 patients, 210 (30.8%) completed 24 weeks of study. Persistence of the HEI group at 6 months was not statistically higher than that of the control group (40.4% vs. 34.9%, p = 0.181). Compliance at 6 months was also similar between the two groups (38.5% vs. 32.5%, p = 0.128). Using OAB symptom score questionnaire, the efficacy of the two groups was not different at each follow-up (p > 0.05). The global response was similar between the two groups. However, the HEI group was more satisfied with treatment than the control group (p = 0.034). The most common reason for discontinuation was satisfaction with the treatment so that they did not need to follow-up, followed by inadequate efficacy in both groups. Adverse events were reported in 12.3% of patients. CONCLUSIONS The health education intervention was not effective to increase drug persistence in OAB patients on anticholinergics.
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Affiliation(s)
- H H Sung
- Department of Urology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Korea
| | - D H Han
- Department of Urology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Korea
| | - T H Kim
- Department of Urology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Korea
| | - Y-S Lee
- Department of Urology, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Korea
| | - H N Lee
- Department of Urology, Seoul Seonam Hospital, Ewha Womans University, Seoul, Korea
| | - J T Seo
- Department of Urology, Cheil General Hospital & Women's Healthcare Center, Dankook University College of Medicine, Seoul, Korea
| | - M-S Choo
- Department of Urology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - K-S Lee
- Department of Urology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Korea
- Department of Medical Device Management & Research, SAIHST, Sungkyunkwan University, Seoul, 06351, Korea
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21
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Lee HN, Lee KS, Kim JC, Chung BH, Kim CS, Lee JG, Kim DK, Park CH, Park JK, Hong SJ. Rate and associated factors of solifenacin add-on after tamsulosin monotherapy in men with voiding and storage lower urinary tract symptoms. Int J Clin Pract 2015; 69:444-53. [PMID: 25363606 DOI: 10.1111/ijcp.12581] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 09/29/2014] [Indexed: 11/27/2022] Open
Abstract
AIM To explore the rate of add-on therapy with solifenacin in men with voiding and storage lower urinary tract symptoms (LUTS) after tamsulosin monotherapy and to explore predictive factors for starting solifenacin add-on therapy. METHODS Men aged ≥ 45 years with IPSS ≥ 12 and symptoms of OAB (OAB-V8 ≥ 8, micturition ≥ 8/24 h, urgency ≥ 2/24 h) were enrolled to receive tamsulosin 0.2 mg once daily. After 4 weeks, men with residual symptoms of OAB and reported 'dissatisfied' or 'a little satisfied' were received solifenacin 5 mg in combination with tamsulosin monotherapy. Subjects completed an IPSS, a Quality of life (QoL) index, OAB V8, and an International Consultation of Incontinence Questionnaire (ICIQ)-Male LUTS, and patient perception of bladder condition (PPBC) at baseline and week 4. RESULTS Of a total of 305 patients, 254 patients completed 4 weeks of tamsulosin treatment. For 176 patients, solifenacin was added (69.3%). Significant predictive factors of solifenacin add-on therapy included long LUTS duration, high IPSS, number of micturitions per 24 h, more urgency episodes, high urgency severity score in a voiding diary and high OAB V8 score. Based on multivariable analysis, potential predictive factors of solifenacin add-on therapy included long LUTS duration (OR = 1.008, 95% CI: 1.001-1.014), high serum PSA (OR = 1.543, 95% CI: 1.136-2.095) and small prostate size (OR = 0.970, 95% CI: 0.947-0.994) (p < 0.05). IPSS, daytime micturitions and urgency episodes, OAB V8 scores, ICIQ and PPBC were improved after tamsulosin monotherapy. CONCLUSIONS Two thirds of men with voiding and storage LUTS needed to add anticholinergics after 4 weeks of tamsulosin monotherapy. Patients with longer lasting symptoms and storage symptoms with small prostate volume may require the anticholinergic add-on.
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Affiliation(s)
- H N Lee
- Department of Urology, Seoul Seonam Hospital, Ewha Womans University, Seoul, Korea
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Lee HN, Mahajan MK, Das S, Sachdeva J, Tiwana MS. Early hematological effects of chemo-radiation therapy in cancer patients and their pattern of recovery - A prospective single institution study. Gulf J Oncolog 2015; 1:43-51. [PMID: 25682452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/08/2014] [Indexed: 06/04/2023]
Abstract
UNLABELLED The purpose of this prospective study is to understand the early hematological effects of chemo-radiation therapy in cancer patients, their pattern of recovery and to ascertain their prognostic value. METHODS 255 diagnosed cancer patients planned for definitive treatment with radiation therapy alone or with chemotherapy were included in this two year prospective study. A complete blood count was done at baseline, weekly during the course of therapy and thereafter, monthly for a period of 6 months. For the purpose of grading clinical toxicity, the Common Toxicity Criteria, CTCAE v2.0 was used while RECIST criteria was used to define the tumor response rates. This study was statistically analyzed using SPSS software. RESULTS 255 patients were included in the study wherein head and neck cancers comprised the major patient population (28.6%) followed by cervix (18.8%) and breast (15.7%). Out of these, 37% in head-and-neck cancer subgroup, and 58.3% in cervix had anemia at start of treatment. 92.2% cases with chemoradiation developed anemia during treatment, while with radiation alone it was 95.5%. This was statistically significant in patients with cancer uterine cervix (p 〈 0.01). At the end of treatment 65% patients with normal hemoglobin had complete responses (CR), while 58.3% with mild anemia and 33.3% with moderate anemia had CR (p=0.1). CONCLUSIONS Severe anemia during treatment is a poor prognostic indicator and is usually a sign of advanced disease. Leucopenia and thrombocytopenia occur more commonly during chemoradiotherapy as against radiotherapy alone, but improves with supportive management.
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Affiliation(s)
- H N Lee
- Dept. of Radiotherapy, Christian Medical College and Hospital, Ludhiana, Punjab 141 008, India
| | - M K Mahajan
- Dept. of Radiotherapy, Christian Medical College and Hospital, Ludhiana, Punjab 141 008, India
| | - S Das
- Dept. of Pathology, Christian Medical College and Hospital, Ludhiana, Punjab 141 008, India
| | - J Sachdeva
- Dept. of Radiotherapy, Christian Medical College and Hospital, Ludhiana, Punjab 141 008, India
| | - M S Tiwana
- Dept. of Radiotherapy, Christian Medical College and Hospital, Ludhiana, Punjab 141 008, India
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Shin KD, Lee HN, Chung T. A revised assay for monitoring autophagic flux in Arabidopsis thaliana reveals involvement of AUTOPHAGY-RELATED9 in autophagy. Mol Cells 2014; 37:399-405. [PMID: 24805779 PMCID: PMC4044311 DOI: 10.14348/molcells.2014.0042] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 03/30/2014] [Accepted: 04/08/2014] [Indexed: 01/29/2023] Open
Abstract
Autophagy targets cytoplasmic cargo to a lytic compartment for degradation. Autophagy-related (Atg) proteins, including the transmembrane protein Atg9, are involved in different steps of autophagy in yeast and mammalian cells. Functional classification of core Atg proteins in plants has not been clearly confirmed, partly because of the limited availability of reliable assays for monitoring autophagic flux. By using proUBQ10-GFP-ATG8a as an autophagic marker, we showed that autophagic flux is reduced but not completely compromised in Arabidopsis thaliana atg9 mutants. In contrast, we confirmed full inhibition of autophagic flux in atg7 and that the difference in autophagy was consistent with the differences in mutant phenotypes such as hypersensitivity to nutrient stress and selective autophagy. Autophagic flux is also reduced by an inhibitor of phosphatidylinositol kinase. Our data indicated that atg9 is phenotypically distinct from atg7 and atg2 in Arabidopsis, and we proposed that ATG9 and phosphatidylinositol kinase activity contribute to efficient autophagy in Arabidopsis.
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Affiliation(s)
- Kwang Deok Shin
- Department of Biological Sciences, Pusan National University, Busan 609-735,
Korea
| | - Han Nim Lee
- Department of Biological Sciences, Pusan National University, Busan 609-735,
Korea
| | - Taijoon Chung
- Department of Biological Sciences, Pusan National University, Busan 609-735,
Korea
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25
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Abstract
Plant seedlings are not photoautotrophs until they are equipped with photosynthetic machinery. Some plant cells are remodeled after being exposed to light, and a group of peroxisomal proteins are degraded during the remodeling. Autophagy was proposed as one of the mechanisms for the degradation of peroxisomal proteins. We recently showed that ATG7-dependent autophagy is partially responsible for the degradation of obsolete peroxisomal proteins during Arabidopsis seedling growth.
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Affiliation(s)
- Jimi Kim
- Department of Biological Sciences; Pusan National University; Busan, Korea
| | - Han Nim Lee
- Department of Biological Sciences; Pusan National University; Busan, Korea
| | - Taijoon Chung
- Department of Biological Sciences; Pusan National University; Busan, Korea
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Lee HN, Tiwana MS, Saini M, Verma SK, Saini M, Jain N, Gupta M, Chauhan N. Superior vena cava obstruction (SVCO) in patients with advanced non small cell lung cancer (NSCLC). Gulf J Oncolog 2014; 1:56-62. [PMID: 24610289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/14/2013] [Indexed: 06/03/2023]
Abstract
INTRODUCTION To report on prognostic and treatment factors influencing the response of SVCO and related survival outcomes in advanced non small cell lung cancer. MATERIAL AND METHODS From November 2008 through December 2011, 18 consecutively diagnosed NSCLC patients with SVCO were included in this study. The patient, tumor and treatment related factors were analyzed. Median overall survival (OS), Kaplan -Meier survival plots, T-test, Cox Proportional Hazards models were generated by multiple covariates (MVA) and analyzed on SPSS software (version 19.0; SPSS, Inc., Chicago, IL). RESULTS Thirteen patients (72%) had presented with SVCO before the pathological diagnosis of underlying lung malignancy, while 5 (28%) progressed to SVCO after initiating treatment with chemotherapy. Twelve (68%) patients achieved subjective relief from the obstruction at the completion of palliative radiation therapy. Treating oncologists preferred 4 Gy per fraction in 11 (62%), while the median biologically equivalent dose delivered was 28 Gy. Six (33%) patients received chemotherapy during the course of treatment. Median OS of the entire cohort was 3±1.85mths and 1-year survival rate of 7%. Univariate analysis confirmed that SVCO patients with good performance score (p=0.02), and partial response to chemotherapy (p= 0.001) have superior OS. However, Cox regression modeling for MVA demonstrated only good performance SVCO patients (p = 0.05) have a better OS. CONCLUSION RT effectively relieves SVCO but overall poor survival associated in our clinical scenario needs to be improved with multimodality approach. Adjuvant chemotherapy is to be considered after initial radiation therapy in good performance patients. KEYWORDS superior vena cava obstruction (SVCO), radiation therapy, chemotherapy, non small cell lung cancer (NSCLC), BED (biologically equivalent dose).
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Affiliation(s)
- H N Lee
- Lee Hsueh Ni, Assistant Professor, Radiation Oncology, STM Cancer Research Institute, Himalayan Institute Hospital Trust, Swami Ram Nagar, Jolly Grant, Dehradun, India 248140. Office Tel. +91 135 2471127. Fax +91 135 2471190.
| | - M S Tiwana
- Surgical Oncology,STM Cancer Research Institute, Himalayan Institute Hospital Trust, Swami Ram Nagar, Jolly Grant, Dehradun, India
| | - M Saini
- Radiodiagnosis, STM Cancer Research Institute, Himalayan Institute Hospital Trust, Swami Ram Nagar, Jolly Grant, Dehradun, India
| | - S K Verma
- Medical Oncology, STM Cancer Research Institute, Himalayan Institute Hospital Trust, Swami Ram Nagar, Jolly Grant, Dehradun, India
| | - M Saini
- Radiodiagnosis, STM Cancer Research Institute, Himalayan Institute Hospital Trust, Swami Ram Nagar, Jolly Grant, Dehradun, India
| | - N Jain
- Surgical Oncology, STM Cancer Research Institute, Himalayan Institute Hospital Trust, Swami Ram Nagar, Jolly Grant, Dehradun, India
| | - M Gupta
- Surgical Oncology, STM Cancer Research Institute, Himalayan Institute Hospital Trust, Swami Ram Nagar, Jolly Grant, Dehradun, India
| | - N Chauhan
- Pathology, STM Cancer Research Institute, Himalayan Institute Hospital Trust, Swami Ram Nagar, Jolly Grant, Dehradun, India
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Abstract
Peroxisomes play a critical role in many metabolic pathways during the plant life cycle. It has been proposed that the transition between different types of peroxisomes involves the degradation of obsolete peroxisomal enzymes via proteolytic activities in the peroxisome matrix, the cytosol, or the vacuole. Forward and reverse genetic studies recently provided evidence for autophagic degradation of peroxisomes in the vacuole of Arabidopsis seedlings. Here, we briefly review a model of pexophagy, or selective autophagy of peroxisomes, in plant cells.
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Affiliation(s)
| | | | - Taijoon Chung
- *Correspondence: Taijoon Chung, Department of Biological Sciences, Pusan National University, 63 Beon-gil2, Busandaehag-ro, Geumjeong-gu, Busan 609-735, South Korea e-mail:
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Kim J, Lee H, Lee HN, Kim SH, Shin KD, Chung T. Autophagy-related proteins are required for degradation of peroxisomes in Arabidopsis hypocotyls during seedling growth. Plant Cell 2013; 25:4956-66. [PMID: 24368791 PMCID: PMC3903998 DOI: 10.1105/tpc.113.117960] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 11/08/2013] [Accepted: 11/29/2013] [Indexed: 05/18/2023]
Abstract
Plant peroxisomes play a pivotal role during postgerminative growth by breaking down fatty acids to provide fixed carbons for seedlings before the onset of photosynthesis. The enzyme composition of peroxisomes changes during the transition of the seedling from a heterotrophic to an autotrophic state; however, the mechanisms for the degradation of obsolete peroxisomal proteins remain elusive. One candidate mechanism is autophagy, a bulk degradation pathway targeting cytoplasmic constituents to the lytic vacuole. We present evidence supporting the autophagy of peroxisomes in Arabidopsis thaliana hypocotyls during seedling growth. Mutants defective in autophagy appeared to accumulate excess peroxisomes in hypocotyl cells. When degradation in the vacuole was pharmacologically compromised, both autophagic bodies and peroxisomal markers were detected in the wild-type vacuole but not in that of the autophagy-incompetent mutants. On the basis of the genetic and cell biological data we obtained, we propose that autophagy is important for the maintenance of peroxisome number and cell remodeling in Arabidopsis hypocotyls.
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Jeen H, Choi WS, Freeland JW, Ohta H, Jung CU, Lee HN. Topotactic phase transformation of the brownmillerite SrCoO2.5 to the perovskite SrCoO3- δ. Adv Mater 2013; 25:3651-3656. [PMID: 23852832 DOI: 10.1002/adma.201300531] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Indexed: 06/02/2023]
Abstract
Pulsed laser epitaxy of brownmillerite SrCoO2.5 thin films and their phase transformation to the perovskite SrCoO3-δ are investigated. While the direct growth of the fully oxidized perovskite films is found to be an arduous task, filling some of oxygen vacancies into SrCoO2.5 by topotactic oxidation accompanies systematic evolution of electronic, magnetic, and thermoelectric properties, useful for many information and energy technologies.
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Affiliation(s)
- H Jeen
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
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Park J, Cho BG, Kim KD, Koo J, Jang H, Ko KT, Park JH, Lee KB, Kim JY, Lee DR, Burns CA, Seo SSA, Lee HN. Oxygen-vacancy-induced orbital reconstruction of Ti ions at the interface of LaAlO3/SrTiO3 heterostructures: a resonant soft-X-ray scattering study. Phys Rev Lett 2013; 110:017401. [PMID: 23383835 DOI: 10.1103/physrevlett.110.017401] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Indexed: 06/01/2023]
Abstract
Resonant soft-x-ray scattering measurements have been performed to investigate interface electronic structures of (LaAlO(3)/SrTiO(3)) superlattices. Resonant scattering intensities at superlattice reflections show clear evidence of degeneracy lifting in t(2g) states of interface Ti ions. Polarization dependence of intensities indicates the energy of d(xy) states is lower by ~1 eV than two other t(2g) states. The energy splitting is insensitive to epitaxial strain. The orbital reconstruction is induced by oxygen vacancies and confined to the interface within two unit cells, indicating charge compensation at the polar interfaces.
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Affiliation(s)
- J Park
- Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea
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Tiwana MS, Uppal B, Sachdeva J, Talole SD, Mahajan MK, Koshy G, Lee HN. Whole saliva physico-biochemical changes and quality of life in head and neck cancer patients following conventional radiation therapy: A prospective longitudinal study. Indian J Cancer 2011; 48:289-95. [DOI: 10.4103/0019-509x.84918] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Ha JE, Jeung IC, Lee YS, Lee HN, Park EK. Clinical analysis of borderline ovarian tumors. EUR J GYNAECOL ONCOL 2011; 32:69-72. [PMID: 21446329] [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: 05/30/2023]
Abstract
PURPOSE The goal of this study was to evaluate the incidence and clinical features of borderline ovarian tumors (BOTS). METHODS We retrospectively performed chart reviews of 22 patients with BOTS who were diagnosed and treated in the university medical center from 1998 to 2009 inclusively. RESULTS BOTS among ovarian pathology in our hospital were detected in 22 patients (1.79%). The mean age was 50 years, range (20-90). Post surgical FIGO staging was Stage I = 86.4%, and Stage II = 13.6%. The most common histologic subtype was mucinous (59%). Five patients (22.7%) had a unilocular cyst at ultrasonography. Conservative surgery was performed in 31.8%. One patient of them had normal spontaneous delivery after term pregnancy. Two patients had a recurrence. One patient with recurrent disease underwent transformation to invasive cancer and died 35 months after the initial diagnosis. CONCLUSION Clinicians should warn patients about the early relapse of BOTS and these patients may need careful follow-up due to the possibility of recurrences.
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Affiliation(s)
- J E Ha
- Department of Obstetrics and Gynecology, College of Medicine, The Catholic University of Korea, Korea
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33
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Kim JO, Baek JM, Jeung C, Park EK, Lee HN, Lee YS. A case of primary ovarian adenomyoma mimicking ovarian malignancy. EUR J GYNAECOL ONCOL 2011; 32:103-106. [PMID: 21446338] [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: 05/30/2023]
Abstract
Adenomyoma is a benign tumor composed of smooth muscle and benign endometrium. These tumors typically originate within the uterus. An extrauterine adenomyoma is an extremely rare entity. After an extensive literature search, only four cases of primary ovarian adenomyoma appear to have thus far been reported. Here, we report a case of ovarian adenomyoma in a 39-year-old woman mimicking malignant neoplasma of the ovary, along with a brief literature review.
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Affiliation(s)
- J O Kim
- Department of Pathology, The Catholic University of Korea, Korea
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Ciaschini PM, Straus SE, Dolovich LR, Goeree RA, Leung KM, Woods CR, Zimmerman GM, Majumdar SR, Spadafora S, Fera LA, Lee HN. Community-based intervention to optimise falls risk management: a randomised controlled trial. Age Ageing 2009; 38:724-30. [PMID: 19767629 DOI: 10.1093/ageing/afp176] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [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: 11/14/2022] Open
Abstract
BACKGROUND falls are the leading causes of accidental death and fragility fractures in older adults. Interventions that assess and reduce falls risk are underutilised. OBJECTIVE to evaluate the impact of a multifaceted community-based programme aimed at optimising evidence-based management of patients at risk for fall-related fractures. DESIGN this was a randomised trial performed from 2003 to 2006. SETTING community-based intervention in Ontario, Canada. PARTICIPANTS eligible patients were community-dwelling, aged > or =55 years and identified to be at risk for fall-related fractures. A total of 201 patients were allocated to the intervention group or to usual care. INTERVENTION components of the intervention included assessment of falls risk, functional status and home environment, and patient education. MEASUREMENTS primary outcome was the implementation of appropriate falls risk assessment at 6 months. Secondary outcomes included falls and fractures at 6 and 12 months. RESULTS the mean age of participants was 72 years, and 41% had fallen with injury in the previous year. Compared to usual care, the intervention increased the number of referrals made to physiotherapy [21% (21/101) vs 6.0% (6/100); relative risk (RR) 3.47, 95% confidence interval (CI) 1.46-8.22] and occupational therapy [15% (15/101) vs 0%; RR 30.7, 95% CI 1.86 to >500]. At 12 months, the number of falls in the intervention group was greater than in the usual care group [23% (23/101) vs 11% (11/100); RR 2.07, 95% CI 1.07-4.02]. CONCLUSIONS compared to usual care, a multi-faceted intervention increased referrals to physiotherapy and occupational therapy but did not reduce risk of falls. Similar falls reduction interventions cannot be recommended based on the results of this study.
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Affiliation(s)
- P M Ciaschini
- Algoma District Medical Group, Sault Ste. Marie, Canada
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35
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Jo JY, Yang SM, Kim TH, Lee HN, Yoon JG, Park S, Jo Y, Jung MH, Noh TW. Nonlinear dynamics of domain-wall propagation in epitaxial ferroelectric thin films. Phys Rev Lett 2009; 102:045701. [PMID: 19257442 DOI: 10.1103/physrevlett.102.045701] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Revised: 11/28/2008] [Indexed: 05/27/2023]
Abstract
We investigated the ferroelectric domain-wall propagation in epitaxial Pb(Zr,Ti)O3 thin film over a wide temperature range (3-300 K). We measured the domain-wall velocity under various electric fields and found that the velocity data is strongly nonlinear with electric fields, especially at low temperature. We found that, as one of surface growth issues, our domain-wall velocity data from ferroelectric epitaxial film could be classified into the creep, depinning, and flow regimes due to competition between disorder and elasticity. The measured values of velocity and dynamical exponents indicate that the ferroelectric domain walls in the epitaxial films are fractal and pinned by a disorder-induced local field.
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Affiliation(s)
- J Y Jo
- Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Korea
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36
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Ciaschini PM, Straus SE, Dolovich LR, Goeree RA, Leung KM, Woods CR, Zimmerman GM, Majumdar SR, Spadafora S, Fera LA, Lee HN. Community-based randomised controlled trial evaluating falls and osteoporosis risk management strategies. Trials 2008; 9:62. [PMID: 18983670 PMCID: PMC2612651 DOI: 10.1186/1745-6215-9-62] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2008] [Accepted: 11/04/2008] [Indexed: 01/06/2023] Open
Abstract
Background Osteoporosis-related fractures are a significant public health concern. Interventions that increase detection and treatment of osteoporosis, as well as prevention of fractures and falls, are substantially underutilized. This paper outlines the protocol for a pragmatic randomised trial of a multifaceted community-based care program aimed at optimizing the evidence-based management of falls and fractures in patients at risk. Design 6-month randomised controlled study. Methods This population-based study was completed in the Algoma District of Ontario, Canada a geographically vast area with Sault Ste Marie (population 78 000) as its main city. Eligible patients were allocated to an immediate intervention protocol (IP) group, or a delayed intervention protocol (DP) group. The DP group received usual care for 6 months and then was crossed over to receive the interventions. Components of the intervention were directed at the physicians and their patients and included patient-specific recommendations for osteoporosis therapy as outlined by the clinical practice guidelines developed by Osteoporosis Canada, and falls risk assessment and treatment. Two primary outcomes were measured including implementation of appropriate osteoporosis and falls risk management. Secondary outcomes included quality of life and the number of falls, fractures, and hospital admissions over a twelve-month period. The patient is the unit of allocation and analysis. Analyses will be performed on an intention to treat basis. Discussion This paper outlines the protocol for a pragmatic randomised trial of a multi-faceted, community-based intervention to optimize the implementation of evidence based management for patients at risk for falls and osteoporosis. Trial Registration This trial has been registered with clinicaltrials.gov (ID: NCT00465387)
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Affiliation(s)
- P M Ciaschini
- Algoma District Medical Group, Sault Ste. Marie, Canada.
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Wolbarst AB, Griggs J, Lee HN, Ren T, Hudson T, White JD, Zhu C. Comparison of environmental radiation monitoring programs in China and the United States. Health Phys 2008; 94:501-511. [PMID: 18469583 DOI: 10.1097/01.hp.0000305823.17036.b3] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The monitoring of environmental radiation has been carried out across the United States by the U.S. Environmental Protection Agency's RadNet (formerly the Environmental Radiation Ambient Monitoring System, ERAMS) and the Global Network Program (GNP) of the Environmental Measurements Laboratory (EML), and in the People's Republic of China (PRC) by their National Radioactivity Contamination Monitoring System (NRCMS). It is expected that an awareness of the similarities and differences in the structure and operation of these programs will prove helpful to both countries and perhaps others as they continue to develop their monitoring capabilities.
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Affiliation(s)
- Anthony B Wolbarst
- College of Health Sciences and College of Medicine, University of Kentucky, Lexington, KY 40536, USA.
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Seo SSA, Choi WS, Lee HN, Yu L, Kim KW, Bernhard C, Noh TW. Optical study of the free-carrier response of LaTiO3/SrTiO3 superlattices. Phys Rev Lett 2007; 99:266801. [PMID: 18233598 DOI: 10.1103/physrevlett.99.266801] [Citation(s) in RCA: 6] [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: 03/06/2007] [Indexed: 05/25/2023]
Abstract
We used infrared spectroscopic ellipsometry to investigate the electronic properties of LaTiO_{3}/SrTiO_{3} superlattices (SLs). Our results indicated that, independent of the SL periodicity and individual layer thickness, the SLs exhibited a Drude metallic response with sheet carrier density per interface approximately 3x10;{14} cm;{-2}. This is probably due to the leakage of d electrons at interfaces from the Mott insulator LaTiO3 to the band insulator SrTiO3. We observed a carrier relaxation time approximately 35 fs and mobility approximately 35 cm;{2} V-1 s;{-1} at 10 K, and an unusual temperature dependence of carrier density that was attributed to the dielectric screening of quantum paraelectric SrTiO3.
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Affiliation(s)
- S S A Seo
- ReCOE & FPRD, Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Korea
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Choi YW, Bae SM, Kim YW, Lee HN, Kim YW, Park TC, Ro DY, Shin JC, Shin SJ, Seo JS, Ahn WS. Gene expression profiles in squamous cell cervical carcinoma using array-based comparative genomic hybridization analysis. Int J Gynecol Cancer 2007; 17:687-96. [PMID: 17504382 DOI: 10.1111/j.1525-1438.2007.00834.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [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: 01/22/2023] Open
Abstract
Our aim was to identify novel genomic regions of interest and provide highly dynamic range information on correlation between squamous cell cervical carcinoma and its related gene expression patterns by a genome-wide array-based comparative genomic hybridization (array-CGH). We analyzed 15 cases of cervical cancer from KangNam St Mary's Hospital of the Catholic University of Korea. Microdissection assay was performed to obtain DNA samples from paraffin-embedded cervical tissues of cancer as well as of the adjacent normal tissues. The bacterial artificial chromosome (BAC) array used in this study consisted of 1440 human BACs and the space among the clones was 2.08 Mb. All the 15 cases of cervical cancer showed the differential changes of the cervical cancer-associated genetic alterations. The analysis limit of average gains and losses was 53%. A significant positive correlation was found in 8q24.3, 1p36.32, 3q27.1, 7p21.1, 11q13.1, and 3p14.2 changes through the cervical carcinogenesis. The regions of high level of gain were 1p36.33-1p36.32, 8q24.3, 16p13.3, 1p36.33, 3q27.1, and 7p21.1. And the regions of homozygous loss were 2q12.1, 22q11.21, 3p14.2, 6q24.3, 7p15.2, and 11q25. In the high level of gain regions, GSDMDC1, RECQL4, TP73, ABCF3, ALG3, HDAC9, ESRRA, and RPS6KA4 were significantly correlated with cervical cancer. The genes encoded by frequently lost clones were PTPRG, GRM7, ZDHHC3, EXOSC7, LRP1B, and NR3C2. Therefore, array-CGH analyses showed that specific genomic alterations were maintained in cervical cancer that were critical to the malignant phenotype and may give a chance to find out possible target genes present in the gained or lost clones.
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Affiliation(s)
- Y-W Choi
- Department of Anesthesiology, College of Medicine, The Catholic University of Korea, Seoul, Korea
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Choi YW, Kim YW, Bae SM, Kwak SY, Chun HJ, Tong SY, Lee HN, Shin JC, Kim KT, Kim YJ, Ahn WS. Identification of differentially expressed genes using annealing control primer-based GeneFishing in human squamous cell cervical carcinoma. Clin Oncol (R Coll Radiol) 2007; 19:308-18. [PMID: 17399965 DOI: 10.1016/j.clon.2007.02.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2005] [Revised: 12/01/2006] [Accepted: 02/13/2007] [Indexed: 01/14/2023]
Abstract
AIMS To compare different gene expression patterns between squamous cell cervical carcinoma (SCC) and normal cervical tissue in Korean women and to identify those genes that are specifically or predominantly expressed in SCC by employing annealing control primer (ACP)-based GeneFishing polymerase chain reaction (PCR). MATERIALS AND METHODS Cervical cancer specimens were obtained from patients enrolled at the Department of Obstetrics and Gynecology, Kang Nam St. Mary's Hospital, Catholic University of Korea. We used a common reference that was mixed with an equal amount of RNA extracted from patients without cervical cancer. The profiles of expressed genes were compared between the SCC and normal cervix identified using GeneFishing differentially expressed gene kits, screened by a BLAST search, and confirmed by semi-quantitative reverse transcription-PCR (RT-PCR). RESULTS Almost 100 differentially expressed genes were identified in the control and SCC samples. Using 60 arbitrary ACPs, 50 differentially expressed genes were identified, and 30 up-regulated and 20 down-regulated expressed genes were sequenced. Among 50 clones selected by ACP-based GeneFishing PCR, six genes with different expression patterns were determined and confirmed by semi-quantitative RT-PCR. The functional roles of two up-regulated genes, fibrillarin and calgranulin A, and one down-regulated gene, clusterin, were previously identified. However, the functional roles of two up-regulated genes and one down-regulated gene were not identified. CONCLUSION We identified distinctive gene expression profiles in Korean women with SCC using ACP-based GeneFishing PCR.
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Affiliation(s)
- Y-W Choi
- Department of Anesthesiology, Catholic University of Korea, Seoul, Republic of Korea
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Kalinin SV, Jesse S, Rodriguez BJ, Shin J, Baddorf AP, Lee HN, Borisevich A, Pennycook SJ. Spatial resolution, information limit, and contrast transfer in piezoresponse force microscopy. Nanotechnology 2006; 17:3400-11. [PMID: 19661582 DOI: 10.1088/0957-4484/17/14/010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Scanning probe-based ferroelectric domain imaging and patterning has attracted broad attention for use in the characterization of ferroelectric materials, ultrahigh density data storage, and nanofabrication. The viability of these applications is limited by the minimal domain size that can be fabricated and reliably detected by scanning probe microscopy. Here, the contrast transfer mechanism in piezoresponse force microscopy (PFM) of ferroelectric materials is analysed in detail. A consistent definition of resolution is developed both for the writing and the imaging processes, and the concept of an information limit in PFM is established. Experimental determination of the object transfer function and the subsequent reconstruction of an 'ideal image' is demonstrated. This contrast transfer theory provides a quantitative basis for image interpretation and allows for the comparison of different instruments in PFM. It is shown that experimentally observed domain sizes can be limited by the resolution of the scanning probe microscope to the order of tens of nanometres even though smaller domains, of the order of several nanometres, can be created.
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Lee HN, Park TS, Lee SY, Huh Y. Spatial filters based on independent component analysis for magnetic noise reduction in the magnetocardiogram. Med Biol Eng Comput 2004; 42:532-4. [PMID: 15320463 DOI: 10.1007/bf02350995] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [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: 11/30/2022]
Abstract
A spatial filter design method to reduce magnetic noise in the magnetocardiogram (MCG) is introduced. Based on the facts that external magnetic noise appearing on multichannel MCG sensors is independent of the cardiac signals and that there is strong spatial correlation among the channels, the independent component analysis (ICA) method was applied to extract the noise components from the measured MCG signals. After extraction of the noise components in a given time period using ICA, a spatial filter was made to reduce the noise components in subsequently acquired MCG signals. In experimental studies of nine healthy volunteers, the spatial filters improved the signal-to-noise ratio of the MCG signals by about 500% on average. This spatial filtering method can be used for measurements of MCG signals in a magnetically noisy environment.
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Affiliation(s)
- H N Lee
- Graduate School of East-West Medical Science, Kyung Hee University, Korea
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Affiliation(s)
- H N Lee
- Department of Dermatology, College of Medicine, The Catholic University of Korea, Seoul, South Korea
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Abstract
Cutaneous endometriosis is characterized by the presence of extrauterine endometrial tissue in or under the skin. We report a case of cutaneous endometriosis in postmenopausal woman who was receiving hormonal replacement.
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Affiliation(s)
- S W Choi
- Department of Dermatology, The Catholic University of Korea, Seoul, Korea
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Lee HN, Cook DJ, Sarabia A, Hatala R, McCallum A, King D, Guyatt GH, Dobranowski J, Powers P. Inadequacy of intravenous heparin therapy in the initial management of venous thromboembolism. J Gen Intern Med 1995; 10:342-5. [PMID: 7562125 DOI: 10.1007/bf02599954] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To determine the adequacy of initial anticoagulation by intravenous heparin for patients who have deep venous thrombosis (DVT), and the factors that influence delayed anticoagulation, independent, duplicate chart review of 63 consecutive patients who had venography-proven DVT was conducted. Adequate heparinization (AH) was defined as an activated partial thromboplastin time (PTT) of more than 1.5 times the normal laboratory control. The proportions of patients achieving AH within 24 hours and 48 hours of initial heparin bolus were 46% and 62%, respectively. Patients who weighed more were less likely to achieve AH (p < 0.05), while patients receiving care from the thromboembolism service were more likely to achieve AH (p < 0.05). Low initial infusion rate was strongly but not significantly predictive of inadequate anticoagulation (p = 0.06). The mean heparin bolus and initial infusion rates were significantly lower than those suggested in the literature (p < 0.01). The AH rates were comparable to historical controls but suboptimal compared with the rates of 66% at 24 hours and 81% at 48 hours reported in association with heparin nomogram use (p < 0.05). A heparin nomogram is likely to achieve consistently higher rates of adequate heparinization.
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Affiliation(s)
- H N Lee
- Department of Medicine, McMaster University Faculty of Health Sciences, Hamilton, Ontario, Canada
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Abstract
We investigated changes in two gonadotropin releasing hormone (GnRH)-containing neuronal populations during juvenile development in the African teleost, Haplochromis burtoni. Juveniles were sampled at weekly intervals and GnRHir neurons were identified through immunocytochemistry (ICC), then counted and measured on computer-captured video images. Soma size of GnRH neurons in the preoptic area (POA), which regulate gonadotropin release from the pituitary, is socially modulated in adults. Here we show that in juveniles the soma size of these neurons increases as a linear function of body weight. Terminal nerve (TN) GnRHir neurons, in contrast, are not involved in pituitary regulation and their soma size is not socially modulated in adults. In juveniles, soma size of these neurons is a quadratic function of body size and the covariance of soma size and body size is much less than in the POA GnRHir neurons. In both populations, GnRHir neuronal number covaries with body size or age only in the earliest juvenile stages. Analysis of the development of these two distinct GnRHir neuronal populations provides insight into their functional differentiation in adults.
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Affiliation(s)
- R C Francis
- Department of Psychology, Stanford University, CA 94305-2130
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Affiliation(s)
- D K Heyland
- Department of Medicine, McMaster University, Faculty of Health Sciences, Hamilton, Canada
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Simon TR, Middleton RA, Barr P, Lee HN, Solis W. Dynamic process captured on a single image: an approach to screening for abnormal superior vena caval flow. J Nucl Med 1986; 27:838-41. [PMID: 3712095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
A strategy for displaying and archiving dynamic quantitative data from scintigraphic imaging is described and applied to diagnosing obstructed thoracic veins. A prospective series of 25 patients with concurrent radiographic contrast and tracer venograms along with 49 controls showed a 33% sensitivity, comparable to previously published data. The use of first harmonic Fourier analysis enhanced the screening value of the test by identifying all abnormals. Moreover, this format captured the dynamic physiologic data on a single photograph. This technique is readily available to nearly any nuclear imaging laboratory equipped with a gamma camera and a computer.
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Saxena VS, Visetsiri E, Sarin P, Lee HN. A limited experience with radiotherapy: can something be done for metastatic malignant liver disease? IMJ Ill Med J 1981; 159:91-4. [PMID: 6110650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Abstract
The clearance characteristics of calcium and the relationship of coupled Na+ and Ca++ renal transport were evaluated in the hypothyroid rat (TX) during volume expansion with 1.5% saline. Despite similar hydropenic plasma calcium, after 11 ml/100 g body wt of infusion volume, the plasma calcium was significantly lower in the TX group (TX, 6.1 +/- 0.2; TI, 7.0 +/- 0.1; P less than .001). With continued infusion, plasma calcium in the TX group continued to drop to 5.3 +/- 0.3 while in the control rats (TI group) it rose to 8.0 +/- 0.1. This marked hypocalcemia in the TX group could not be explained by urinary losses of calcium, hemodilution, deficient parathyroid response, or changes in ultrafilterable plasma calcium. The higher fractional calcium excretion found in the TX group paralleled the higher fractional sodium excretion, and the coupling between calcium and sodium excretion was preserved in hypothyroidism under these conditions. Our results indicate an abnormal calcium homeostasis in the hypothyroid rat. The data do not support a renal cause for this disturbance but are consistent with the view that mobilization of calcium from the bone is sluggish in hypothyroidism during volume expansion.
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