1
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Lin SZ, Changede R, Farrugia AJ, Bershadsky AD, Sheetz MP, Prost J, Rupprecht JF. Membrane Tilt Drives Phase Separation of Adhesion Receptors. Phys Rev Lett 2024; 132:188402. [PMID: 38759206 DOI: 10.1103/physrevlett.132.188402] [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] [Received: 08/31/2023] [Accepted: 03/25/2024] [Indexed: 05/19/2024]
Abstract
Cell adhesion receptors are transmembrane proteins that bind cells to their environment. These proteins typically cluster into disk-shaped or linear structures. Here, we show that such clustering patterns spontaneously emerge when the receptor senses the membrane deformation gradient, for example, by reaching a lower-energy conformation when the membrane is tilted relative to the underlying binding substrate. Increasing the strength of the membrane gradient-sensing mechanism first yields isolated disk-shaped clusters and then long linear structures. Our theory is coherent with experimental estimates of the parameters, suggesting that a tilt-induced clustering mechanism is relevant in the context of cell adhesion.
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Affiliation(s)
- Shao-Zhen Lin
- Aix Marseille Univ, Université de Toulon, CNRS, CPT (UMR 7332), Turing Centre for Living Systems, Marseille, France
| | - Rishita Changede
- Mechanobiology Institute, National University of Singapore, 117411 Singapore
- TeOra Pte Ltd, Singapore, Singapore
| | - Aaron J Farrugia
- Mechanobiology Institute, National University of Singapore, 117411 Singapore
| | - Alexander D Bershadsky
- Mechanobiology Institute, National University of Singapore, 117411 Singapore
- Department of Molecular Cell Biology, Weizmann Institute of Science, Israel
| | - Michael P Sheetz
- Mechanobiology Institute, National University of Singapore, 117411 Singapore
- Biochemistry and Molecular Biology Department, University of Texas Medical Branch, Galveston, Texas 77555, USA
| | - Jacques Prost
- Mechanobiology Institute, National University of Singapore, 117411 Singapore
- Laboratoire Physico-Chimie Curie, UMR 168, Institut Curie, PSL Research University, CNRS, Sorbonne Université, 75005 Paris, France
| | - Jean-François Rupprecht
- Aix Marseille Univ, Université de Toulon, CNRS, CPT (UMR 7332), Turing Centre for Living Systems, Marseille, France
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2
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Guan LY, Lin SZ, Chen PC, Lv JQ, Li B, Feng XQ. Interfacial Organization and Forces Arising from Epithelial-Cancerous Monolayer Interactions. ACS Nano 2023; 17:24668-24684. [PMID: 38091551 DOI: 10.1021/acsnano.3c03990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
The interfacial interactions between epithelia and cancer cells have profound relevance for tumor development and metastasis. Through monolayer confrontation of MCF10A (nontumorigenic human breast epithelial cells) and MDA-MB-231 (human epithelial breast cancer cells) cells, we investigate the epithelial-cancerous interfacial interactions at the tissue level. We show that the monolayer interaction leads to competitive interfacial morphodynamics and drives an intricate spatial organization of MCF10A cells into multicellular finger-like structures, which further branch into multiple subfinger-like structures. These hierarchical interfacial structures penetrate the cancer monolayer and can spontaneously segregate or even envelop cancer cell clusters, consistent with our theoretical prediction. By tracking the substrate displacements via embedded fluorescent nanobeads and implementing nanomechanical modeling that combines atomic force microscopy and finite element simulations, we computed mechanical force patterns, including traction forces and monolayer stresses, caused by the monolayer interaction. It is found that the heterogeneous mechanical forces accumulated in the monolayers are able to squeeze cancer cells, leading to three-dimensional interfacial bulges or cell extrusion, initiating the p53 apoptosis signaling pathways of cancer cells. We reveal that intercellular E-cadherin and P-cadherin of epithelial cells differentially regulate the interfacial organization including migration speed, directionality, spatial correlation, F-actin alignment, and subcellular protrusions of MCF10A cells; whereas E-cadherin governs interfacial geometry that is relevant to force localization and cancer cell extrusion, P-cadherin maintains interfacial integrity that enables long-range force transmission. Our findings suggest that the collaborative molecular and mechanical behaviors are crucial for preventing epithelial tissues from undergoing tumor invasion.
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Affiliation(s)
- Liu-Yuan Guan
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Shao-Zhen Lin
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Peng-Cheng Chen
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Jian-Qing Lv
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Bo Li
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Xi-Qiao Feng
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
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3
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Nishizawa K, Lin SZ, Chardès C, Rupprecht JF, Lenne PF. Two-point optical manipulation reveals mechanosensitive remodeling of cell-cell contacts in vivo. Proc Natl Acad Sci U S A 2023; 120:e2212389120. [PMID: 36947511 PMCID: PMC10068846 DOI: 10.1073/pnas.2212389120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 01/17/2023] [Indexed: 03/23/2023] Open
Abstract
Biological tissues acquire reproducible shapes during development through dynamic cell behaviors. Most of these behaviors involve the remodeling of cell-cell contacts. During epithelial morphogenesis, contractile actomyosin networks remodel cell-cell contacts by shrinking and extending junctions between lateral cell surfaces. However, actomyosin networks not only generate mechanical stresses but also respond to them, confounding our understanding of how mechanical stresses remodel cell-cell contacts. Here, we develop a two-point optical manipulation method to impose different stress patterns on cell-cell contacts in the early epithelium of the Drosophila embryo. The technique allows us to produce junction extension and shrinkage through different push and pull manipulations at the edges of junctions. We use these observations to expand classical vertex-based models of tissue mechanics, incorporating negative and positive mechanosensitive feedback depending on the type of remodeling. In particular, we show that Myosin-II activity responds to junction strain rate and facilitates full junction shrinkage. Altogether our work provides insight into how stress produces efficient deformation of cell-cell contacts in vivo and identifies unanticipated mechanosensitive features of their remodeling.
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Affiliation(s)
- Kenji Nishizawa
- Aix Marseille Univ, CNRS, IBDM, Turing Centre for Living systems, Marseille UMR 7288, France
| | - Shao-Zhen Lin
- Aix Marseille Univ, Université de Toulon, CNRS, CPT, Turing Centre for Living systems, Marseille UMR 7332, France
| | - Claire Chardès
- Aix Marseille Univ, CNRS, IBDM, Turing Centre for Living systems, Marseille UMR 7288, France
| | - Jean-François Rupprecht
- Aix Marseille Univ, Université de Toulon, CNRS, CPT, Turing Centre for Living systems, Marseille UMR 7332, France
| | - Pierre-François Lenne
- Aix Marseille Univ, CNRS, IBDM, Turing Centre for Living systems, Marseille UMR 7288, France
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4
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Lin SZ, Merkel M, Rupprecht JF. Structure and Rheology in Vertex Models under Cell-Shape-Dependent Active Stresses. Phys Rev Lett 2023; 130:058202. [PMID: 36800465 DOI: 10.1103/physrevlett.130.058202] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 08/19/2022] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Abstract
Biological cells can actively tune their intracellular architecture according to their overall shape. Here we explore the rheological implication of such coupling in a minimal model of a dense cellular material where each cell exerts an active mechanical stress along its axis of elongation. Increasing the active stress amplitude leads to several transitions. An initially hexagonal crystal motif is first destabilized into a solid with anisotropic cells whose shear modulus eventually vanishes at a first critical activity. Increasing activity beyond this first critical value, we find a re-entrant transition to a regime with finite hexatic order and finite shear modulus, in which cells arrange according to a rhombile pattern with periodically arranged rosette structures. The shear modulus vanishes again at a third threshold beyond which spontaneous tissue flows and topological defects of the nematic cell shape field arise. Flow and stress fields around the defects agree with active nematic theory, with either contractile or extensile signs, as also observed in several epithelial tissue experiments.
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Affiliation(s)
- Shao-Zhen Lin
- Aix Marseille Université, Université de Toulon, CNRS, Centre de Physique Théorique, Turing Center for Living Systems, Marseille, France
| | - Matthias Merkel
- Aix Marseille Université, Université de Toulon, CNRS, Centre de Physique Théorique, Turing Center for Living Systems, Marseille, France
| | - Jean-François Rupprecht
- Aix Marseille Université, Université de Toulon, CNRS, Centre de Physique Théorique, Turing Center for Living Systems, Marseille, France
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5
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Sonam S, Balasubramaniam L, Lin SZ, Ivan YMY, Jaumà IP, Jebane C, Karnat M, Toyama Y, Marcq P, Prost J, Mège RM, Rupprecht JF, Ladoux B. Mechanical stress driven by rigidity sensing governs epithelial stability. Nat Phys 2023; 19:132-141. [PMID: 36686215 PMCID: PMC7614076 DOI: 10.1038/s41567-022-01826-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Epithelia act as a barrier against environmental stress and abrasion and in vivo they are continuously exposed to environments of various mechanical properties. The impact of this environment on epithelial integrity remains elusive. By culturing epithelial cells on 2D hydrogels, we observe a loss of epithelial monolayer integrity through spontaneous hole formation when grown on soft substrates. Substrate stiffness triggers an unanticipated mechanical switch of epithelial monolayers from tensile on soft to compressive on stiff substrates. Through active nematic modelling, we find that spontaneous half-integer defect formation underpinning large isotropic stress fluctuations initiate hole opening events. Our data show that monolayer rupture due to high tensile stress is promoted by the weakening of cell-cell junctions that could be induced by cell division events or local cellular stretching. Our results show that substrate stiffness provides feedback on monolayer mechanical state and that topological defects can trigger stochastic mechanical failure, with potential application towards a mechanistic understanding of compromised epithelial integrity during immune response and morphogenesis.
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Affiliation(s)
- Surabhi Sonam
- Université de Paris, CNRS, Institut Jacques Monod, F-75006 Paris, France
| | | | - Shao-Zhen Lin
- Aix Marseille Univ, Université de Toulon, CNRS, CPT, Turing Center for Living Systems, Marseille, France
| | | | - Irina Pi Jaumà
- Université de Paris, CNRS, Institut Jacques Monod, F-75006 Paris, France
| | - Cecile Jebane
- Université de Paris, CNRS, Institut Jacques Monod, F-75006 Paris, France
| | - Marc Karnat
- Aix Marseille Univ, Université de Toulon, CNRS, CPT, Turing Center for Living Systems, Marseille, France
| | - Yusuke Toyama
- Mechanobiology Institute, National University of Singapore, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Philippe Marcq
- Physique et Mécanique des Milieux Hétérogènes, CNRS, ESPCI Paris, PSL University, Sorbonne Université, Université de Paris, 75005, Paris, France
| | - Jacques Prost
- Mechanobiology Institute, National University of Singapore, Singapore
- Physico-Chimie Curie, Institut Curie, CNRS UMR 168, Paris, France
| | - René-Marc Mège
- Université de Paris, CNRS, Institut Jacques Monod, F-75006 Paris, France
| | - Jean-François Rupprecht
- Aix Marseille Univ, Université de Toulon, CNRS, CPT, Turing Center for Living Systems, Marseille, France
- Corresponding authors Dr. Benoit Ladoux, , Dr. Jean-François Rupprecht,
| | - Benoît Ladoux
- Université de Paris, CNRS, Institut Jacques Monod, F-75006 Paris, France
- Corresponding authors Dr. Benoit Ladoux, , Dr. Jean-François Rupprecht,
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6
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Liu Z, Wu MH, Wang QX, Lin SZ, Feng XQ, Li B, Liang X. Drosophila mechanical nociceptors preferentially sense localized poking. eLife 2022; 11:76574. [PMID: 36200757 DOI: 10.7554/elife.76574] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 10/05/2022] [Indexed: 11/13/2022] Open
Abstract
Mechanical nociception is an evolutionarily conserved sensory process required for the survival of living organisms. Previous studies have revealed much about the neural circuits and sensory molecules in mechanical nociception, but the cellular mechanisms adopted by nociceptors in force detection remain elusive. To address this issue, we study the mechanosensation of a fly larval nociceptor (class IV da neurons, c4da) using a customized mechanical device. We find that c4da are sensitive to mN-scale forces and make uniform responses to the forces applied at different dendritic regions. Moreover, c4da showed a greater sensitivity to localized forces, consistent with them being able to detect the poking of sharp objects, such as wasp ovipositor. Further analysis reveals that high morphological complexity, mechanosensitivity to lateral tension and possibly also active signal propagation in dendrites contribute to the sensory features of c4da. In particular, we discover that Piezo and Ppk1/Ppk26, two key mechanosensory molecules, make differential but additive contributions to the mechanosensitivity of c4da. In all, our results provide updates into understanding how c4da process mechanical signals at the cellular level and reveal the contributions of key molecules.
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Affiliation(s)
- Zhen Liu
- School of Life Sciences, Tsinghua University, Tsinghua, China
| | - Meng-Hua Wu
- School of Life Sciences, Tsinghua University, Tsinghua, China
| | - Qi-Xuan Wang
- School of Life Sciences, Tsinghua University, Tsinghua, China
| | - Shao-Zhen Lin
- Department of Engineering Mechanics, Tsinghua University, Tsinghua, China
| | - Xi-Qiao Feng
- Department of Engineering Mechanics, Tsinghua University, Tsinghua, China
| | - Bo Li
- Department of Engineering Mechanics, Tsinghua University, Tsinghua, China
| | - Xin Liang
- School of Life Sciences, Tsinghua University, Tsinghua, China
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7
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Li ZY, Zhang DQ, Lin SZ, Góźdź WT, Li B. Spontaneous organization and phase separation of skyrmions in chiral active matter. Soft Matter 2022; 18:7348-7359. [PMID: 36124977 DOI: 10.1039/d2sm00819j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Skyrmions are topologically protected vortex-like excitations that hold promise for applications such as information processing and electron manipulation. Here we combine theoretical analysis and numerical simulations to show that skyrmions can spontaneously emerge in chiral active matter without external confinements or regulation. Strikingly, these activity-driven skyrmions can either self-organize into a periodic, stable square lattice consisting of half Néel skyrmions and antiskyrmions, where the in-plane flows display an antiferromagnetic vortex array, or undergo phase separation between skyrmions with different topological numbers. We identify that the emerging skyrmion dynamics stems from the competition between the chiral and polar coherence length scales dictated by the interplay of intrinsic chirality, polarity, and elasticity in the system. Our results reveal unanticipated topological excitations, self-organization, and phase separation in non-equilibrium systems and also suggest a potential way towards engineering complicated bespoke skyrmionic structures through manipulating active matter.
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Affiliation(s)
- Zhong-Yi Li
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.
| | - De-Qing Zhang
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.
| | - Shao-Zhen Lin
- Aix Marseille Université, CNRS, Centre de Physique Théorique, Turing Center for Living Systems, 13009 Marseille, France
| | - Wojciech T Góźdź
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Bo Li
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.
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8
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Abstract
Cell monolayers are a central model system in the study of tissue biophysics. In vivo, epithelial tissues are curved on the scale of microns, and the curvature's role in the onset of spontaneous tissue flows is still not well understood. Here, we present a hydrodynamic theory for an apical-basal asymmetric active nematic gel on a curved strip. We show that surface curvature qualitatively changes monolayer motion compared with flat space: the resulting flows can be thresholdless, and the transition to motion may change from continuous to discontinuous. Surface curvature, friction, and active tractions are all shown to control the flow pattern selected, from simple shear to vortex chains.
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Affiliation(s)
- Samuel Bell
- Laboratoire Physico-Chimie Curie, UMR 168, Institut Curie, PSL Research University, CNRS, Sorbonne Université, 75005 Paris, France
| | - Shao-Zhen Lin
- Aix Marseille Université, Université de Toulon, CNRS, Centre de Physique Théorique, Turing Center for Living Systems, 13288 Marseille, France
| | - Jean-François Rupprecht
- Aix Marseille Université, Université de Toulon, CNRS, Centre de Physique Théorique, Turing Center for Living Systems, 13288 Marseille, France
| | - Jacques Prost
- Laboratoire Physico-Chimie Curie, UMR 168, Institut Curie, PSL Research University, CNRS, Sorbonne Université, 75005 Paris, France
- Mechanobiology Institute, National University of Singapore, 117411 Singapore
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9
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Lin SZ, Merkel M, Rupprecht JF. Implementation of cellular bulk stresses in vertex models of biological tissues. Eur Phys J E Soft Matter 2022; 45:4. [PMID: 35038043 DOI: 10.1140/epje/s10189-021-00154-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 12/01/2021] [Indexed: 06/14/2023]
Abstract
Vertex models describe biological tissues as tilings of polygons. In standard vertex models, the tissue dynamics result from a balance between isotropic stresses, which are associated with the bulk of the cells, and tensions associated with cell-cell interfaces. However, in this framework it is less obvious how to describe anisotropic stresses arising from the bulk of cells. In epithelia, such bulk anisotropic stresses could arise for instance through medial myosin fluctuations. Two recent publications-Tlili et al. (Proc Natl Acad Sci USA 116(51):25430-25439, 2019) and Comelles et al. (eLife 10:e57730, 2021)-have proposed different schemes to implement bulk anisotropic stresses in vertex models. Here we show that while both schemes transform in the same way under affine deformations, they lead to significantly different tissue dynamics. Our results are consistent with the interpretation that the Tilli et al. scheme describes bulk stresses that are uniform within each cell, while the Comelles et al. scheme corresponds to non-uniform bulk stresses. Finally, we wondered whether a standard vertex model can be fully expressed in terms of bulk cellular stresses alone. We find that, in general, neither scheme can mimic the vertex forces created by cell-cell interface tensions.
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Affiliation(s)
- Shao-Zhen Lin
- CNRS and Turing Center for Living Systems, Centre de Physique Théorique, Aix Marseille Univ, Université de Toulon, 13009, Marseille, France
| | - Matthias Merkel
- CNRS and Turing Center for Living Systems, Centre de Physique Théorique, Aix Marseille Univ, Université de Toulon, 13009, Marseille, France
| | - Jean-Francois Rupprecht
- CNRS and Turing Center for Living Systems, Centre de Physique Théorique, Aix Marseille Univ, Université de Toulon, 13009, Marseille, France.
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10
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Li ZY, Zhang DQ, Lin SZ, Li B. Pattern Formation and Defect Ordering in Active Chiral Nematics. Phys Rev Lett 2020; 125:098002. [PMID: 32915620 DOI: 10.1103/physrevlett.125.098002] [Citation(s) in RCA: 3] [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: 02/28/2020] [Accepted: 08/04/2020] [Indexed: 06/11/2023]
Abstract
Many biological systems display intriguing chiral patterns and dynamics. Here, we present an active nematic theory accounting for individual spin to explore the collective handedness in chiral rod-shaped aggregations. We show that coordinated individual spin and motility can engender a vortex-array pattern with chirality and drive ordering of topological defects. During this chiral process, the stationary trefoil-like defects self-organize into a periodic, hexagon-dominated polygonal network, which segregates persistently rotating cometlike defects in pairs within each polygon, leading to a translation symmetry at the global scale while a broken reflection symmetry at the local scale. Such defect ordering agrees exactly with the Voronoi tiling of two-dimensional space and the emergence of the hexagonal symmetry is deciphered in analogy with topological charge neutralization. We calculate energy barriers to the topological transition of the defect ordering and explain the existing metastable states with nonhexagonal polygons. Our findings shed light on the chiral morphodynamics in life processes and also suggest a potential route towards tuning self-organization in active materials.
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Affiliation(s)
- Zhong-Yi Li
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - De-Qing Zhang
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Shao-Zhen Lin
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Bo Li
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
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11
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Abstract
Cellular dynamic behaviors in organ morphogenesis and embryogenesis are affected by geometrical constraints. In this paper, we investigate how the surface topology and curvature of the underlying substrate tailor collective cell migration. An active vertex model is developed to explore the collective dynamics of coherent cells crawling on curved surfaces. We show that cells can self-organize into rich dynamic patterns including local swirling, global rotation, spiral crawling, serpentine crawling, and directed migration, depending on the interplay between cell-cell interactions and geometric constraints. Increasing substrate curvature results in higher cell-cell bending energy and thus tends to suppress local swirling and enhance density fluctuations. Substrate topology is revealed to regulate both the collective migration modes and density fluctuations of cell populations. In addition, upon increasing noise intensity, a Kosterlitz-Thouless-like ordering transition can emerge on both undevelopable and developable surfaces. This study paves the way to investigate various in vivo morphomechanics that involve surface curvature and topology.
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Affiliation(s)
- Shao-Zhen Lin
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.
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12
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Lin SZ, Bi D, Li B, Feng XQ. Dynamic instability and migration modes of collective cells in channels. J R Soc Interface 2019; 16:20190258. [PMID: 31362619 PMCID: PMC6685016 DOI: 10.1098/rsif.2019.0258] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/03/2019] [Indexed: 12/31/2022] Open
Abstract
Migrating cells constantly experience geometrical confinements in vivo, as exemplified by cancer invasion and embryo development. In this paper, we investigate how intrinsic cellular properties and extrinsic channel confinements jointly regulate the two-dimensional migratory dynamics of collective cells. We find that besides external confinement, active cell motility and cell crowdedness also shape the migration modes of collective cells. Furthermore, the effects of active cell motility, cell crowdedness and confinement size on collective cell migration can be integrated into a unified dimensionless parameter, defined as the cellular motility number (CMN), which mirrors the competition between active motile force and passive elastic restoring force of cells. A low CMN favours laminar-like cell flows, while a high CMN destabilizes cell motions, resulting in a series of mode transitions from a laminar phase to an ordered vortex chain, and further to a mesoscale turbulent phase. These findings not only explain recent experiments but also predict dynamic behaviours of cell collectives, such as the existence of an ordered vortex chain mode and the mode selection under non-straight confinements, which are experimentally testable across different epithelial cell lines.
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Affiliation(s)
- Shao-Zhen Lin
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, People's Republic of China
| | - Dapeng Bi
- Department of Physics, Northeastern University, Boston, MA 02115, USA
| | - Bo Li
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, People's Republic of China
| | - Xi-Qiao Feng
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, People's Republic of China
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13
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Chen PC, Lin SZ, Xu GK, Li B, Feng XQ. Three-dimensional collective cell motions in an acinus-like lumen. J Biomech 2019; 84:234-242. [PMID: 30661732 DOI: 10.1016/j.jbiomech.2019.01.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 11/28/2018] [Accepted: 01/03/2019] [Indexed: 11/16/2022]
Abstract
Collective cell migration is an essential process in embryo development, wound healing, inflammatory response, and cancer invasion. Although cell motions in two-dimensional (2D) monolayers have been studied previously, three-dimensional (3D) collective cell migration, which constantly occurs during embryogenesis such as the establishment of ducts and acini in vivo, remains elusive. In this paper, we develop a cell-based model incorporating cell mechanics and cell motility to address coherent cell motions in a spherical acinus-like lumen with different cell populations. It is found that the interplays between cell persistence, random fluctuation, and geometrical confinement may engender rich and novel migratory modes. In a 3D spherical lumen, two cells may undergo stripe-like or cross-circular coherent rotations, whereas multiple cells can form dynamic twisting or circulating bands, leaving sparse cells at the center or even a hollow cavity in the cell aggregate. The cell density is found to profoundly influence the collective cell migration modes. Our model can reproduce the fundamental features observed in experiments and highlight the role of mechanics in steering 3D collective cell dynamics during mammary acinar morphogenesis.
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Affiliation(s)
- Peng-Cheng Chen
- Institute of Biomechanics and Medical Engineering, AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Shao-Zhen Lin
- Institute of Biomechanics and Medical Engineering, AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Guang-Kui Xu
- Department of Engineering Mechanics, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University, Xi'an 710049, China
| | - Bo Li
- Institute of Biomechanics and Medical Engineering, AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.
| | - Xi-Qiao Feng
- Institute of Biomechanics and Medical Engineering, AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
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14
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Lin SZ, Ye S, Xu GK, Li B, Feng XQ. Dynamic Migration Modes of Collective Cells. Biophys J 2018; 115:1826-1835. [PMID: 30297134 PMCID: PMC6224637 DOI: 10.1016/j.bpj.2018.09.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [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: 06/20/2018] [Revised: 08/24/2018] [Accepted: 09/13/2018] [Indexed: 12/12/2022] Open
Abstract
Collective cell migration occurs in a diversity of physiological processes such as wound healing, cancer metastasis, and embryonic morphogenesis. In the collective context, cohesive cells may move as a translational solid, swirl as a fluid, or even rotate like a disk, with scales ranging from several to dozens of cells. In this work, an active vertex model is presented to explore the regulatory roles of social interactions of neighboring cells and environmental confinements in collective cell migration in a confluent monolayer. It is found that the competition between two kinds of intercellular social interactions-local alignment and contact inhibition of locomotion-drives the cells to self-organize into various dynamic coherent structures with a spatial correlation scale. The interplay between this intrinsic length scale and the external confinement dictates the migration modes of collective cells confined in a finite space. We also show that the local alignment-contact inhibition of locomotion coordination can induce giant density fluctuations in a confluent cell monolayer without gaps, which triggers the spontaneous breaking of orientational symmetry and leads to phase separation.
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Affiliation(s)
- Shao-Zhen Lin
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing, China
| | - Sang Ye
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing, China
| | - Guang-Kui Xu
- International Center for Applied Mechanics, State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi'an Jiaotong University, Xi'an, China
| | - Bo Li
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing, China.
| | - Xi-Qiao Feng
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing, China.
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15
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Lin SZ, Dong HJ, Sun JP. [Expanding test and normalization for HIV/AIDS prevention and control]. Zhonghua Yu Fang Yi Xue Za Zhi 2017; 50:929-931. [PMID: 27903351 DOI: 10.3760/cma.j.issn.0253-9624.2016.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Expanding real-name HIV test is the basis of the real-time reporting system in China, and it plays an important role for the progress. In year of 2003, there were 45 092 cases of HIV positives reported cumulatively, which accounted for only 5.4% of the estimated population of HIV positives. Since implementation of real-name HIV test and establishment, real-time reporting system, up to year 2005, the total of reported HIV positives was 577 000, which took up 67.9% of the estimated HIV positives. Also among reported cases, 387 000 cases have received the anti-retroviral treatment. Normalization of HIV prevention and control will pave the way to medical insurance for HIV positives. It is a goal that all the people have medical insurance in China, and the normalization is an ideal working condition, and real-name HIV test is a measure for it. The both are very closely connected and improving each anther.
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Affiliation(s)
- S Z Lin
- School of Public Health, Zhejiang University, Hangzhou 310058, China
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16
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Xue SL, Lin SZ, Li B, Feng XQ. A nonlinear poroelastic theory of solid tumors with glycosaminoglycan swelling. J Theor Biol 2017; 433:49-56. [PMID: 28859927 DOI: 10.1016/j.jtbi.2017.08.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 07/12/2017] [Accepted: 08/26/2017] [Indexed: 12/18/2022]
Abstract
Mechanics plays a crucial role in the growth, development, and therapeutics of tumors. In this paper, a nonlinear poroelastic theory is established to describe the mechanical behaviors of solid tumors. The free-swollen state of a tumor is chosen as the reference state, which enables us to avoid pursuing a dry and stress-free state that is hard to achieve for living tissues. Our results reveal that the compression resistance of a tumor is primarily attributed to glycosaminoglycan (GAG) swelling, and the compactness of cell aggregates is found to affect tumor consolidation. Over-expressed GAGs and dense cell aggregates can stiffen the tumor, a remodeling mechanism that makes the tumor with higher elastic modulus than its surrounding host tissues. Glycosaminoglycan chains also influence the transient mechanical response of the tumor by modulating the tissue permeability. The theoretical results show good agreement with relevant experimental observations. This study may not only deepen our understanding of tumorigenesis but also provide cues for developing novel anticancer strategies.
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Affiliation(s)
- Shi-Lei Xue
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing, 100084, P R China
| | - Shao-Zhen Lin
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing, 100084, P R China
| | - Bo Li
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing, 100084, P R China.
| | - Xi-Qiao Feng
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing, 100084, P R China.
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17
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Abstract
Oscillatory morphodynamics provides necessary mechanical cues for many multicellular processes. Owing to their collective nature, these processes require robustly coordinated dynamics of individual cells, which are often separated too distantly to communicate with each other through biomaterial transportation. Although it is known that the mechanical balance generally plays a significant role in the systems' morphologies, it remains elusive whether and how the mechanical components may contribute to the systems' collective morphodynamics. Here, we study the collective oscillations in the Drosophila amnioserosa tissue to elucidate the regulatory roles of the mechanical components. We identify that the tensile stress is the key activator that switches the collective oscillations on and off. This regulatory role is shown analytically using the Hopf bifurcation theory. We find that the physical properties of the tissue boundary are directly responsible for synchronizing the oscillatory intensity and polarity of all inner cells and for orchestrating the spatial oscillation patterns inthe tissue.
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Affiliation(s)
- Shao-Zhen Lin
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Bo Li
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China;
| | - Ganhui Lan
- Department of Physics, George Washington University, Washington DC 20052;
| | - Xi-Qiao Feng
- Institute of Biomechanics and Medical Engineering, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China;
- Center for Advanced Mechanics and Materials, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
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18
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Dela Peña I, Sanberg PR, Acosta S, Tajiri N, Lin SZ, Borlongan CV. Stem cells and G-CSF for treating neuroinflammation in traumatic brain injury: aging as a comorbidity factor. J Neurosurg Sci 2014; 58:145-149. [PMID: 24844175 PMCID: PMC4117389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Traumatic brain injury (TBI), often called the signature wound of Iraq and Afghanistan wars, is characterized by a progressive histopathology and long-lasting behavioral deficits. Treatment options for TBI are limited and patients are usually relegated to rehabilitation therapy and a handful of experimental treatments. Stem cell-based therapies offer alternative treatment regimens for TBI, and have been intended to target the delayed therapeutic window post-TBI, in order to promote "neuroregeneration," in lieu of "neuroprotection" which can be accomplished during acute TBI phase. However, these interventions may require adjunctive pharmacological treatments especially when aging is considered as a comorbidity factor for post-TBI health outcomes. Here, we put forward the concept that a combination therapy of human umbilical cord blood cell (hUCB) and granulocyte-colony stimulating factor (G-CSF) attenuates neuroinflammation in TBI, in view of the safety and efficacy profiles of hUCB and G-CSF, their respective mechanisms of action, and efficacy of hUCB+G-CSF combination therapy in TBI animal models. Further investigations on the neuroinflammatory pathway as a key pathological hallmark in acute and chronic TBI and also as a major therapeutic target of hUCB+G-CSF are warranted in order to optimize the translation of this combination therapy in the clinic.
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Affiliation(s)
- I Dela Peña
- Center of Excellence for Aging and Brain Repair Department of Neurosurgery and Brain Repair University of South Florida Morsani College of Medicine Tampa, FL, USA -
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19
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Lin SZ, Zheng B. Short-time critical dynamics at perfect and imperfect surfaces. Phys Rev E Stat Nonlin Soft Matter Phys 2008; 78:011127. [PMID: 18763939 DOI: 10.1103/physreve.78.011127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2008] [Indexed: 05/26/2023]
Abstract
With Monte Carlo simulations, we study the dynamic relaxation at perfect and imperfect surfaces of the three-dimensional Ising model with an ordered initial state. The time evolution of the surface magnetization, the line magnetization of the defect line, and the corresponding susceptibilities and second cumulants is carefully examined. Universal dynamic scaling forms including a dynamic crossover scaling form are identified at the ordinary, special, and surface phase transitions. The critical exponents beta1 of the surface magnetization and beta2 of the line magnetization are extracted. The impact of the defect line on the universality classes is investigated.
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Affiliation(s)
- S Z Lin
- Zhejiang Institute of Modern Physics, Zhejiang University, Hangzhou, China
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20
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Yang KL, Chu CC, Huang CH, Lin SZ, Hsu WL, Liu DW, Lin PY. Discovery of HLA-DRB1*0331 in a Taiwanese marrow donor and the importance of sequence-based typing in a rare or previously unrecognized allele. Int J Immunogenet 2007; 34:91-5. [PMID: 17373933 DOI: 10.1111/j.1744-313x.2007.00662.x] [Citation(s) in RCA: 13] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We describe here a novel HLA-DRB1* allele, DRB1*0331, observed from a Taiwanese bone marrow donor using DNA sequence-based typing (SBT) method. The 'new' allele differs from DRB1*0306 and DRB1*0325 by one nucleotide at positions 196 and 227, respectively. Nucleotide mutations caused amino acid substitutions from N to Y at codon 37 and from F to Y at codon 47, as compared with amino acid sequence encoded by the DRB1*030101 allele. The donor was first typed as DRB1*0403/0406/0439/0441/0446/0451/0452 (NMDP code DRB1*04XX) and DRB1*0304/0323/0325 (NMDP code DRB1*03APDA) by sequence-specific oligonucleotide (SSO) typing kit. Subsequent typing of the donor by high-resolution sequence-specific primer (SSP) protocol indicated DRB1*0403 and DRB1*0306. The anomalous result of DRB1*03 was resolved by SBT and recognized as DRB1*0331. We concluded that SSP or SSO alone may mistype a precedent unrecognized allele and that two different typing techniques or SBT may have to be employed to safe guard true HLA typing when rare alleles are encountered at the first time.
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Affiliation(s)
- K L Yang
- Laboratory of Immunogenetics, Tzu-Chi Stem Cells Centre, Buddhist Tzu-Chi Marrow Donor Registry, Hualien, Taiwan.
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21
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Lin SZ, Zheng B, Trimper S. Computer simulations of two-dimensional melting with dipole-dipole interactions. Phys Rev E Stat Nonlin Soft Matter Phys 2006; 73:066106. [PMID: 16906913 DOI: 10.1103/physreve.73.066106] [Citation(s) in RCA: 7] [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: 08/23/2005] [Revised: 03/20/2006] [Indexed: 05/11/2023]
Abstract
We perform molecular dynamics and Monte Carlo simulations of two-dimensional melting with dipole-dipole interactions. Both static and dynamic behaviors are examined. In the isotropic liquid phase, the bond orientational correlation length xi 6 and susceptibility chi 6 are measured, and the data are fitted to the theoretical ansatz. An algebraic decay is detected for both spatial and temporal bond orientational correlation functions in an intermediate temperature regime, and it provides an explicit evidence for the existence of the hexatic phase. From the finite-size scaling analysis of the global bond orientational order parameter, the disclination unbinding temperature Ti is estimated. In addition, from dynamic Monte Carlo simulations of the positional order parameter, we extract the critical exponents at the dislocation unbinding temperature Tm. All the results are in agreement with those from experiments and support the Kosterlitz-Thouless-Halperin-Nelson-Young (KTHNY) theory.
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Affiliation(s)
- S Z Lin
- Zhejiang University, Zhejiang Institute of Modern Physics, Hangzhou 310027, People's Republic of China
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22
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Abstract
Stem cell therapies are an important strategy for the treatment of stroke. Bone marrow-derived stem cells (BMSCs) may promote structural and functional repair in several organs via stem cell plasticity. The tissue damage could stimulate the stem cells migration, and they track into the site of damage and then undergo differentiation. The plasticity functions of BMSCs in an injuries tissue are dependent on the specific signals present in the local environment of the damaged tissue. Recent studies have also identified the specific molecular signals, such as SDF-1/CXCR4, required for the interaction of BMSCs and damaged host tissues. This review summarizes the current understanding of how BMSCs reach and function in cerebral ischemic tissues.
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Affiliation(s)
- D D Liu
- Department of Dentistry, Tzu-Chi Buddhist General Hospital, Tzu-Chi University, Hualien, Taiwan
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Lin JJ, Chen CH, Yueh KC, Chang CY, Lin SZ. A CD14 monocyte receptor polymorphism and genetic susceptibility to Parkinson's disease for females. Parkinsonism Relat Disord 2006; 12:9-13. [PMID: 16337421 DOI: 10.1016/j.parkreldis.2005.07.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [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] [Received: 02/28/2005] [Revised: 07/11/2005] [Accepted: 07/13/2005] [Indexed: 11/21/2022]
Abstract
Recent studies suggest that inflammation may play an important role in the pathogenesis of Parkinson's disease (PD). Because the C(-260) --> T polymorphism in the promoter of the CD14 monocyte receptor gene (pCD14) could affect the predisposition to the inflammatory response, we conducted a case-control study to investigate a possible genetic susceptibility of the pCD14 polymorphism in patients with PD. This study included 200 sporadic PD patients and 200 controls, matched by sex and case-control pairs for age at onset in the case. All observed genotype frequencies were in Hardy-Weinberg equilibrium. Results revealed that the CD14-T allele of the pCD14 polymorphism in the female PD patients existed statistically significant difference from that of the female controls (OR = 1.262, P = 0.038), but not for male. Female individuals with homozygote CD14-TT genotype were significantly increased risk of PD by 1.28 time (P = 0.027). Furthermore, a logistic regression analysis confirmed that the homozygote CD14-TT genotype was an independent risk factor for PD (OR = 1.576, P = 0.030). In conclusion, results of this study indicate the pCD14 polymorphism to be a genetic risk factor for PD in females.
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Affiliation(s)
- J J Lin
- Department of Neurology, Chushang Show-Chwan Hospital, Nantou, 557, Taiwan, ROC.
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24
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Lin JJ, Yueh KC, Chang CY, Chen CH, Lin SZ. The homozygote AA genotype of the α1-antichymotrypsin gene may confer protection against early-onset Parkinson's disease in women. Parkinsonism Relat Disord 2004; 10:469-73. [PMID: 15542006 DOI: 10.1016/j.parkreldis.2004.06.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
There has been increasing evidence suggesting that inflammatory response maybe involved in the pathogenesis of Parkinson's disease (PD). Alpha1-antichymotrypsin gene (ACT) has been regarded as a susceptibility factor for PD in the past, but the evidence remains controversial. This case-control study was designed to investigate the association of alpha1-antichymotrypsin gene (ACT) polymorphism between 210 Taiwanese patients with clinical definite sporadic PD and 260 controls, matched by age and sex. There were no differences of allelic frequency (A and T) and genotype polymorphism (AA, AT and TT) of the ACT in PD patients from the controls. However, there were significantly fewer early-onset PD (onset age younger than 60 years) or PD women carrying the homozygote AA genotype (ACT-AA) than in controls (p=0.046 and 0.044, respectively). Further analysis revealed that the reduced risk of ACT-AA was particularly significant among PD women with the onset age younger than 60 years (OR=0.796, 95% CI=0.749-0.847, p<0.0001). This study shows that ACT-AA may confer a modest protection against developing early-onset PD in women.
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Affiliation(s)
- J J Lin
- Department of Neurology, Chushang Show-Chwan Hospital, 75 Sec. 2 Chi-Shang Road, Chushang Jenn, Nantou 557, Taiwan.
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Lee CC, Lin SZ, Wang Y, Lin JJ, Liu JY, Chen GJ, Chiang YH, Liu JC, Zhou FC. First human ventral mesencephalon and striatum cografting in a Parkinson patient. Acta Neurochir Suppl 2003; 87:159-62. [PMID: 14518545 DOI: 10.1007/978-3-7091-6081-7_33] [Citation(s) in RCA: 4] [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] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
Fetal ventral mesencephalon (VM) transplantation has been reported to improve parkinsonian symptoms. Animal studies show that cografting of striatal tissue increases the survival of dopamine neurons. Whether or not VM and striatum cografting could ameliorate motor dysfunction in a Parkinson's disease (PD) patient was explored in this study. The patient was a 53-year-old male who had presented with symptoms of tremor, rigidity and bradykinesia for 11 years. He had been treated with L-dopa and had progressive deterioration of symptoms even with the daily dosage of L-dopa increased to 900 mg per day. Before transplantation, his PD symptoms were scored with Unified Parkinson's Disease Rating Scale (UPDRS) and video recordings. The influx constant (ki) of the [18F] 6-fluoro-L-dopa uptake in the striatum was measured by positron emission tomography (PET) imaging. The fetal VM and the lateral part of the lateral ganglionic eminence (LGE) were cografted into the right putamen and, one week later, fetal VM alone was transplanted into the left putamen. After the transplantation, the patient's UPDRS score improved from 128 to 62 at 6 months and to 24 at 22 months during the "off" phase. The score of daily living disability improved from 35 to 18 at 6 months and to 10 at 22 months post transplantation. Twenty-two months after grafting, "off" phases were almost absent, and the freezing had totally disappeared. The [18F] 6-fluoro-L-dopa PET studies were performed 1 month before and 21 months after transplantation. The ki for [18F] 6-fluoro-L-dopa was decreased by 15% in the right caudate and 5% in the left caudate, both of which did not have any ventral mesencephalic grafts. However, the ki was increased by 35%, in the left non-cografted putamen, and by 58% in the right cografted putamen. In conclusion, cografting the fetal VM and the LGE in the putamen may improve the motor function of PD patients.
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Affiliation(s)
- C C Lee
- Department of Radiology, Neuro-Medical Scientific Center, Tzu-Chi General Hospital, Tzu-Chi University, Hualien, Taiwan
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Lee-Chen GJ, Lin SP, Lin SZ, Chuang CK, Hsiao KT, Huang CF, Lien WC. Identification and characterisation of mutations underlying Sanfilippo syndrome type B (mucopolysaccharidosis type IIIB). J Med Genet 2002; 39:E3. [PMID: 11836372 PMCID: PMC1735050 DOI: 10.1136/jmg.39.2.e3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- G J Lee-Chen
- Department of Biology, National Taiwan Normal University, Taipei, Taiwan, ROC
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Huang WS, Lin SZ, Lin JC, Wey SP, Ting G, Liu RS. Evaluation of early-stage Parkinson's disease with 99mTc-TRODAT-1 imaging. J Nucl Med 2001; 42:1303-8. [PMID: 11535717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
UNLABELLED Parkinson's disease is a progressive neurodegenerative disorder characterized by a selective loss of dopamine in the striatum. Problems remain in the accurate diagnosis of Parkinson's disease. A 99mTc-labeled tropane derivative that binds to dopamine transporter with high selectivity is [2-[[2-[[[3-(4-chlorophenyl)-8-methyl-8-azabicyclo[3,2,1]oct-2-yl]methyl](2-mercaptoethyl)amino]ethyl]amino]ethanethiolato(3-)-N2,N2',S2,S2']oxo-[1R-(exo-exo)] (TRODAT-1). The purpose of this study was to investigate the potential usefulness of 99mTc-TRODAT-1 imaging in the evaluation of patients with early-stage Parkinson's disease. METHODS Thirty-four patients with early-stage idiopathic Parkinson's disease were recruited. For all patients, the Parkinson's disease was stage 2 or less as assessed by the Hoehn and Yahr scale. Seventeen age-matched healthy volunteers (8 men, 9 women) served as controls. 99mTc-TRODAT-1 was prepared from a lyophilized kit. Brain SPECT imaging was performed between 165 and 195 min after injection, using a double-head camera equipped with fanbeam collimators. Specific uptake in the striatum and its subregions, including the putamen and caudate nucleus, was calculated and compared with that of the other sides and of healthy volunteers. RESULTS A continuous reduction in specific striatal uptake of 99mTc-TRODAT-1 with increasing disease severity was found in Parkinson's disease patients (control vs. stage I vs. stage II, 1.98 vs. 1.62 vs. 1.22, respectively, P < 0.01). The changes were magnified by measurement of specific putaminal uptake (control vs. stage I vs. stage II, 1.81 vs. 1.27 vs. 0.94, respectively, P < 0.01). The mean values of specific putaminal uptake contralateral to the more affected limbs were significantly decreased compared with the ipsilateral sides in both stage I and stage II groups (1.02 vs. 1.49 for stage I and 0.73 vs. 1.14 for stage II, P < 0.01). Moreover, a significant loss of putaminal uptake ipsilateral to the symptoms was found in the stage I group compared with the healthy volunteers (1.49 vs. 1.81, P < 0.01). The difference became greater when the posterior putaminal uptakes were compared. No remarkable adverse reactions were found in either healthy volunteers or Parkinson's disease patients during or after imaging. CONCLUSION For clinical practice, 99mTc-TRODAT-1 may serve as a useful imaging agent for the early detection of Parkinson's disease.
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Affiliation(s)
- W S Huang
- Department of Nuclear Medicine, National Defense Medical Center, Tri-Service General Hospital, Taipei, Taiwan
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Wang Y, Chang CF, Morales M, Chou J, Chen HL, Chiang YH, Lin SZ, Cadet JL, Deng X, Wang JY, Chen SY, Kaplan PL, Hoffer BJ. Bone morphogenetic protein-6 reduces ischemia-induced brain damage in rats. Stroke 2001; 32:2170-8. [PMID: 11546913 DOI: 10.1161/hs0901.095650] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Bone morphogenetic protein-6 (BMP6) and its receptors are expressed in adult and fetal brain. Receptors for BMP6 are upregulated in adult brain after injury, leading to the suggestion that BMP6 is involved in the physiological response to neuronal injury. The purpose of this study was to determine whether there was a neuroprotective effect of BMP6 in vivo and in vitro. METHODS Lactate dehydrogenase and microtubule-associated protein-2 (MAP-2) activities were used to determine the protective effect of BMP6 against H(2)O(2) in primary cortical cultures. The neuroprotective effects of BMP6 were also studied in chloral hydrate-anesthetized rats. BMP6 or vehicle was injected into right cerebral cortex before transient right middle cerebral artery (MCA) ligation. Animals were killed for triphenyl-tetrazolium chloride staining, caspase-3 immunoreactivity and enzymatic assays, and TUNEL assay. A subgroup of animals were used for locomotor behavioral assays. RESULTS Application of H(2)O(2) increased lactate dehydrogenase activity and decreased the density of MAP-2(+) neurons in culture. Both responses were attenuated by BMP6 pretreatment. Complementary in vivo studies showed that pretreatment with BMP6 increased motor performance and generated less cerebral infarction induced by MCA ligation/reperfusion in rats. Pretreatment with BMP6 did not alter cerebral blood flow or physiological parameters. There was decreased ischemia-induced caspase-3 immunoreactivity, caspase-3 enzymatic activity, and density of TUNEL-positive cells in ischemic cortex in BMP6-treated animals. CONCLUSIONS BMP6 reduces ischemia/reperfusion injury, perhaps by attenuating molecular events underlying apoptosis.
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Affiliation(s)
- Y Wang
- National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA.
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Lin JJ, Lin SZ, Lin GY, Chang DC, Lee CC. Treatment of intractable generalized dystonia by bilateral posteroventral pallidotomy--one-year results. Zhonghua Yi Xue Za Zhi (Taipei) 2001; 64:231-8. [PMID: 11458761] [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: 02/20/2023]
Abstract
BACKGROUND Recent study has revealed that bilateral posteroventral pallidotomy (PVP) significantly improve dystonic movements and improve motor function of those patients with generalized dystonia (GD). However, there is only a limited number of patients who have been reported so far. METHODS This study was conducted to evaluate the clinical efficacy of surgical treatment with bilateral PVP on patients with intractable GD. All the studied patients were regularly rated with standardized scales (Burke-Fahn-Marsden Evaluation Scale for Dystonia) for dystonic movement and living disability before and after surgery. RESULTS There were 18 patients, 8 males and 10 females with an average age of 24.8 years, included in the study. Postoperatively, there were slow, partial, but steady improvements of the dystonic movement and daily living function. Maximal effects were noted at the sixth month and the clinical benefits were sustained one year after the surgical treatment when there were statistically significant improvements in 13% of total dystonia movement score and 9% of the total disability score (p < 0.05). Upon further analysis, improvements of dystonic movements were statistically significant in the regions of mouth (50%), speech/swallowing (19%) and neck (43%), and daily living functions in speech (14%) and eating/swallowing (29%). CONCLUSIONS Bilateral posteroventral pallidotomy was only partially effective for the treatment of GD, and it produced clinical improvement in the dystonic movement limited to the craniocervical region. We therefore suggest that patients with GD should be carefully selected for the treatment of bilateral posteroventral pallidotomy, despite the surgery having a partially beneficial effect on this kind of movement.
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Affiliation(s)
- J J Lin
- Department of Neurology, Chushang Show-Chwan Hospital, 75, Sec. 2, Chi-Shang Road, Chushang, Nantou 557, Taiwan.
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Wang Y, Hayashi T, Chang CF, Chiang YH, Tsao LI, Su TP, Borlongan C, Lin SZ. Methamphetamine potentiates ischemia/reperfusion insults after transient middle cerebral artery ligation. Stroke 2001; 32:775-82. [PMID: 11239201 DOI: 10.1161/01.str.32.3.775] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [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: 01/08/2023]
Abstract
BACKGROUND AND PURPOSE Previous studies have indicated that both methamphetamine (MA) and ischemia/reperfusion injuries involve reactive oxygen species formation and activation of apoptotic mechanism. That MA could have a synergistic or additive effect with stroke-induced brain damage is possible. The purpose of the present study was to investigate whether administration of MA in vivo would potentiate ischemic brain injury. METHODS Adult CD-1 mice were pretreated with MA or saline. Each animal later was anesthetized with chloral hydrate and placed in a stereotaxic frame. A subset of animals received intracerebral administration of glial cell line-derived neurotrophic factor (GDNF). The right middle cerebral artery and bilateral carotids were transiently occluded for 45 minutes. Regional cerebral blood flow was measured by laser Doppler. Animals were sacrificed for triphenyltetrazolium chloride staining and p53 mRNA Northern blot assay after 24 hours of reperfusion. Cortical and striatal GDNF levels were assayed by ELISA. RESULTS We found that pretreatment with MA increased ischemia-induced cerebral infarction. Ischemia or MA alone enhanced p53 mRNA expression. Moreover, MA potentiated expression of p53 mRNA in the ischemic mouse brain. MA pretreatment decreased GDNF levels in ischemic striatum. Intracerebral administration of GDNF before ischemia reduced MA-facilitated infarction. CONCLUSIONS Our data indicate that MA exacerbates ischemic insults in brain, perhaps through the inhibition of GDNF-mediated pathways and suggest that MA may antagonize endogenous neuroprotective pathways as part of its mechanism of action.
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Affiliation(s)
- Y Wang
- National Institute on Drug Abuse, I.R.P., 5500 Nathan Shock Dr, Baltimore, MD 21224, USA.
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Tsai TH, Chen SL, Chiang YH, Lin SZ, Ma HI, Kuo SW, Tsao YP. Recombinant adeno-associated virus vector expressing glial cell line-derived neurotrophic factor reduces ischemia-induced damage. Exp Neurol 2000; 166:266-75. [PMID: 11085892 DOI: 10.1006/exnr.2000.7505] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [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: 11/22/2022]
Abstract
To explore the potential of using the recombinant adeno-associated viral (rAAV) vector, expressing glial cell line-derived neurotrophic factor (GDNF) as the gene therapy for stroke, we injected rAAV vectors expressing GDNF (rAAV-GDNF) into the cortex of rats which had been experiencing transient bilateral common carotid artery ligation and right middle cerebral artery ligation for 90 min. GDNF levels in cortical tissues of rAAV-GDNF-injected animals were significantly higher than in the control animals injected with rAAV-expressing lacZ (rAAV-lacZ), indicating that rAAV can deliver and express the GDNF gene in cortical tissues. Triphenyltetrazolium chloride tissue stain analysis revealed that the rAAV-delivered GDNF gene could rescue the brain tissues from ischemia-induced injury. Cortical tissues which received rAAV-GDNF injections had both significantly smaller total volumes of infarction and smaller areas of infarction on each brain slice than those which were injected with rAAV-lacZ. An in situ labeling analysis demonstrated significantly less apoptotic cells in cortical tissues rescued by rAAV-GDNF, indicating prevention of apoptosis as the mechanism of cortical cell protection. Moreover, immunohistochemistry staining of Neu-N indicated that the rescued brain tissues contained the same number of Neu-N-positive neuronal cells as contralateral undamaged brain tissues. This provides strong evidence that cortical neuronal cells can be rescued by GDNF gene therapy. Indeed, these findings show that the rAAV is a potential delivery vector of GDNF gene for the therapy of stroke.
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Affiliation(s)
- T H Tsai
- Department of Microbiology and Immunology, National Defense Medical Center, Taipei, Republic of China
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Zheng SQ, Li T, Xuan YX, Lin SZ, Chen LJ, Yan GM. [Neuroprotective effect of alpha-dihydroergocryptine depends on activation of nuclear factor kappa B]. Yao Xue Xue Bao 2000; 35:898-901. [PMID: 12567910] [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: 02/28/2023]
Abstract
AIM To investigate the relationship between the neuroprotective effect of alpha-dihydroergocryptine (alpha-DHEC) and the activation of nuclear factor Kappa B (NF-Kappa B). METHODS Adult male rats were subjected to cerebral ischemia induced by middle cerebral artery occlusion (MCAO). DNA binding activity of NF-Kappa B was determined with electrophoretic mobility shift assay (EMSA) in animals subjected to varying durations of cerebral ischemia. Neuroapoptosis induced by ischemic damage was measured by deoxynucleotidy transferase-mediated dUTP nick end labeling (TUNEL) assay and flow cytometry (FCM) analysis. RESULTS No change was observed in nuclear NF-Kappa B DNA binding in normal animal. A low level of constitutive NF-Kappa B DNA binding was detected in animals subjected to cerebral ischemia of 1 h, and significant increase in the amount of active NF-Kappa B in nuclear extracts was observed after cerebral ischemia of 3 h, 6 h, and 12 h. Peak of NF-Kappa B DNA binding was observed at the time point of 3 h. Animals subjected to cerebral ischemia of 3 h potentially initiates neuroapoptosis and activates NF-Kappa B in nuclear extract. Alpha-DHEC (100 micrograms.kg-1 and 150 micrograms.kg-1) showed significant protective effect on neuroapoptosis-induced by cerebral ischemia of 3 h, and inhibiting NF-Kappa B activation using 100 mg.kg-1 pyrrolidinedithiocarbamate (PDTC) in the continuous presence of alpha-DHEC, the neuroprotective effect of alpha-DHEC was blocked. CONCLUSION The findings suggest that the neuroprotetive effect of alpha-DHEC may depend on the activation of NF-Kappa B.
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Affiliation(s)
- S Q Zheng
- Department of Pharmacology, Sun Yat-Sen University of Medical Science, Guangzhou 510080, China
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Yang XH, Lin SZ. [Treatment of diseased middle turbinate in endoscopic sinus surgery]. Lin Chuang Er Bi Yan Hou Ke Za Zhi 2000; 14:354-6. [PMID: 12563895] [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: 04/20/2023]
Abstract
OBJECTIVE To study the clinical significance of reservation of the middle turbinate in functional endoscopic sinus surgery (FESS) for sinusitis and/or nasal polyps. METHOD According to anatomic criteria of the middle turbinate surgery in adult, 32 cases who had sinusitis and/or nasal polyps were treated and followed up. The recovery of middle turbinate contour, postoperative ethmoid cavity and the rate of patency of the maxillary sinus ostium were observed postoperatively. RESULT 1. After 6 months, the form of middle turbinate returned to normal in 24 cases (75%), adhesions occurred in 8 cases (25%), including the closure of ethmoid sinus cavity in 2 cases. 2. The patency of maxillary sinuses ostium maintained well in 25 cases (78.1%), stenosed in 6 cases (18.8%) and closed in 1 case (3.1%). The diseased middle turbinate can recover to normal contour in most cases, often plastics in FESS. CONCLUSION Reservation of middle turbinate plays an important role in promoting the clinical cure rate.
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Affiliation(s)
- X H Yang
- First Affiliated Hospital, Guiyang Medical College, Guiyang 550004
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Lee WH, Chen A, Chao DG, Harn HJ, Lin SZ. Malignant meningioma with rhabdoid transformation. Zhonghua Yi Xue Za Zhi (Taipei) 2000; 63:492-7. [PMID: 10925541] [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: 02/17/2023]
Abstract
We report a rare case of recurrent meningioma with malignant change and rhabdoid transformation in a 54-year-old woman who presented with severe headache and progressive weakness of the right extremities. The patient had a history of atypical meningioma and had undergone a craniotomy to remove a tumor nine years earlier. We discuss the distinctive morphologic, immunohistochemical staining and ultrastructural features of a recurrent malignant meningioma. A meningioma with rhabdoid transformation may indicate aggressive biologic and clinical behavior of the tumor.
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Affiliation(s)
- W H Lee
- Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, National Defense University, Taipei, Taiwan, ROC
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35
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Tomac AC, Grinberg A, Huang SP, Nosrat C, Wang Y, Borlongan C, Lin SZ, Chiang YH, Olson L, Westphal H, Hoffer BJ. Glial cell line-derived neurotrophic factor receptor alpha1 availability regulates glial cell line-derived neurotrophic factor signaling: evidence from mice carrying one or two mutated alleles. Neuroscience 2000; 95:1011-23. [PMID: 10682708 DOI: 10.1016/s0306-4522(99)00503-5] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Glial cell line-derived neurotrophic factor receptor alpha1 (GFRalpha1, also known as GDNFR-alpha) is a glycolipid-anchored membrane protein of the GFRalpha family, which binds glial cell line-derived neurotrophic factor [Jing S. et al. (1996) Cell 85, 1113-1124; Treanor J. J. et al. (1996) Nature 382, 80-83], a survival factor for several populations of central and peripheral neurons, including midbrain dopamine neurons [Lin L. F. et al. (1993) Science 260, 1130-1132], and mediates its ligand-induced cell response via a tyrosine kinase receptor called Ret [Takahashi M. et al. (1988) Oncogene 3, 571-578; Takahashi M. and Cooper G. M. (1987) Molec. Cell Biol. 7, 1378-1385]. In this paper, we show that mice with a null mutation of the GFRalpha1 gene manifest epithelial-mesenchymal interaction deficits in kidney and severe disturbances of intestinal tract development similar to those seen with glial cell line-derived neurotrophic factor or Ret null mutations. There is a marked renal dysgenesis or agenesis and the intrinsic enteric nervous system fails completely to develop. We also show that newborn GFRalpha1-deficient mice display no or minimal changes in dorsal root and sympathetic ganglia. This is in contrast to the deficits reported in these neuronal populations in glial cell line-derived neurotrophic factor and Ret null mutations. Mesencephalic dopaminergic neurons in the substantia nigra and ventral tegmental area appear intact at the time of birth of the mutated mice. Mice homozygous for the GFRalpha1 null mutation die within 24 h of birth because of uremia. Heterozygous animals, however, live to adulthood. There is a significantly reduced neuroprotective effect of glial cell line-derived neurotrophic factor in such heterozygous animals, compared with wild-type littermates, after cerebral ischemia. Taken together with previous data on glial cell line-derived neurotrophic factor and Ret, our results strongly suggest that GFRalpha1 is the essential GFRalpha receptor for signaling in the glial cell line-derived neurotrophic factor-Ret pathway in the kidney and enteric nervous system development, and that GFRalpha2 or GFRalpha3 cannot substitute for the absence of GFRalpha1. Moreover, neuroprotective actions of exogenous glial cell line-derived neurotrophic factor also require full GFRalpha1 receptor expression.
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Affiliation(s)
- A C Tomac
- Laboratory of Mammalian Genes and Development, National Institutes of Health, Bethesda, MD 20892, USA
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Wang Y, Chiang YH, Su TP, Hayashi T, Morales M, Hoffer BJ, Lin SZ. Vitamin D(3) attenuates cortical infarction induced by middle cerebral arterial ligation in rats. Neuropharmacology 2000; 39:873-80. [PMID: 10699453 DOI: 10.1016/s0028-3908(99)00255-5] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.5] [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: 11/19/2022]
Abstract
We have previously reported that intracerebral administration of glial cell line derived neurotrophic factor (GDNF) reduces the extent of middle cerebral arterial (MCA) ligation-induced cortical infarction in rats. Recent studies have shown that application of 1, 25 dihydroxyvitamin D(3) (D3) enhances GDNF mRNA expression in vitro. The purpose of the present study was to investigate if administration of D3 in vivo will protect against ischemic brain injury. Adult male Sprague-Dawley rats were injected daily with D3 or with saline for four or eight days. Animals received a 90-min right MCA ligation on the 4(th) or 8(th) day after anesthesia with chloral hydrate. Animals were sacrificed for tri-phenyl-tetrazolium chloride (TTC) staining 24 h after the onset of reperfusion. A subset of animals receiving eight days of D3 or saline treatment were used for blood gas and cerebral GDNF protein level analysis. We found that pretreatment with D3 for four days did not attenuate the ischemic injury. However, animals receiving eight days of D3 injections showed a significant reduction in the amount of infarction in the cortex. Eight day D3 treatment did not alter blood gases or blood pressure; however, it did increase calcium levels. Pretreatment with D3 significantly increased GDNF levels in the cortex. In conclusion, our data indicate that D3 reduces ischemia-induced brain damage and supports the hypothesis that this effect may be through the up-regulation of GDNF mechanisms in cortex.
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Affiliation(s)
- Y Wang
- National Institute on Drug Abuse, NIH, Baltimore, MD, USA.
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Wang WY, Li MT, Pi RB, Qiu PX, Su XW, Lin SZ, Yan GM. Antagonistic action of caffeine against LY294002-induced apoptosis in cerebellar granule neurons. Acta Pharmacol Sin 2000; 21:35-40. [PMID: 11263245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
AIM To study the effect of caffeine on apoptosis induced by inhibition of 1-phosphatidylinositol 3-kinase in cerebellar granule neurons. METHODS Cerebellar granule neurons culture, agar gel electrophoresis, and stress-activated protein kinase (SAPK)/c-Jun N-terminal protein kinase (JNK) assay kit to measure SAPK/JNK activity. RESULTS LY294002 evoked apoptosis concentration-dependently in cerebellar granule neurons. But death resulting from LY294002 was prevented by caffeine in a concentration-dependent manner. The survival effect of caffeine was not affected by inhibitors of ryanodine-sensitive Ca2+ release, nor was it inhibited by L-type channel blockers and N-methyl-D-aspartate (NMDA) receptor blocker. In addition, RP-cAMP, H89, and KN62 were not able to inhibit the protective effect of caffeine. Phosphorylation of c-Jun was necessary for the induction of apoptosis induced by LY294002 in cerebellar granule neurons. But caffeine directly inhibited the activation of JNK and decreased phospho-c-Jun in granule neurons. CONCLUSION Caffeine inhibited the activation of JNK and decreased the phosphorylation of c-Jun to protect granule neurons from LY294002-induced apoptosis.
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Affiliation(s)
- W Y Wang
- Department of Pharmacology, Guangzhou Medical College of PLA, Guangzhou 510315, China
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Chiang YH, Lin SZ, Borlongan CV, Hoffer BJ, Morales M, Wang Y. Transplantation of fetal kidney tissue reduces cerebral infarction induced by middle cerebral artery ligation. J Cereb Blood Flow Metab 1999; 19:1329-35. [PMID: 10598937 DOI: 10.1097/00004647-199912000-00006] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [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: 11/26/2022]
Abstract
The authors, and others, have recently reported that intracerebral administration of glial cell line-derived neurotrophic factor (GDNF) or osteogenic protein-1 protects against ischemia-induced injury in the cerebral cortex of adult rats. Because these trophic factors are highly expressed in the fetal, but not adult, kidney cortex, the possibility that transplantation of fetal kidney tissue could serve as a cellular reservoir for such molecules and protect against ischemic injury in cerebral cortex was examined. Fetal kidneys obtained from rat embryos at gestational day 16, and adult kidney cortex, were dissected and cut into small pieces. Adult male Sprague-Dawley rats were anesthetized with chloral hydrate and placed in a stereotactic apparatus. Kidney tissues were transplanted into three cortical areas adjacent to the right middle cerebral artery (MCA). Thirty minutes after grafting, the right MCA was transiently ligated for 90 minutes. Twenty-four hours after the onset of reperfusion, animals were evaluated behaviorally. It was found that the stroke animals that received adult kidney transplantation developed motor imbalance. However, animals that received fetal kidney grafts showed significant behavioral improvement. Animals were later sacrificed and brains were removed for triphenyltetrazolium chloride staining, Pax-2 immunostaining, and GDNF mRNA expression. It was noted that transplantation of fetal kidney but not adult kidney tissue greatly reduced the volume of infarction in the cerebral cortex. Fetal kidney grafts showed Pax-2 immunoreactivity and GDNF mRNA in the host cerebral cortex. In contrast, GDNF mRNA expression was not found in the adult kidney grafts. Taken together, our data indicate that fetal kidney transplantation reduces ischemia/reperfusion-induced cortical infarction and behavioral deficits in adult rats, and that such tissue grafts could serve as an unique cellular reservoir for trophic factor application to the brain.
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Affiliation(s)
- Y H Chiang
- Department of Neurosurgery, Tri-Service General Hospital National Defense Medical Center, Taipei, Taiwan
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Lin JJ, Yueh KC, Chang DC, Lin SZ. Absence of G209A and G88C mutations in the alpha-synuclein gene of Parkinson's disease in a Chinese population. Eur Neurol 1999; 42:217-20. [PMID: 10567818 DOI: 10.1159/000008110] [Citation(s) in RCA: 16] [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] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A G209A mutation in the alpha-synuclein gene was recently discovered in a large Italian kindred and three unrelated Greek kindreds with autosomal dominant Parkinson's disease (PD). Subsequently, another mutation in the gene (G88C) was also identified in a German family with autosomal PD. These results indicate that the alpha-synuclein gene may have an important role in the pathogenesis of PD. This study was designed to screen the existence of both mutations of the alpha-synuclein gene among 100 Chinese patients with PD, including 80 with sporadic and 20 with familial PD. Results showed that none of our patients, both sporadic and familial PD, had either of the two mutations of this gene. We therefore conclude that although of great interest, these two mutations are not relevant for the pathogenesis of PD in a Han Chinese population.
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Affiliation(s)
- J J Lin
- Department of Neurology, Parkinson's Disease and Movement Disorders Clinic, Chushang Show-Chwan Hospital, Nantou, Taiwan, ROC.
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Liu DM, Lin SZ, Wang SD, Wu MY, Wang Y. Xenografting human T2 sympathetic ganglion from hyperhidrotic patients provides short-term restoration of catecholaminergic functions in hemiparkinsonian athymic rats. Cell Transplant 1999; 8:583-91. [PMID: 10701487 DOI: 10.1177/096368979900800604] [Citation(s) in RCA: 6] [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: 11/15/2022] Open
Abstract
Previous studies have suggested that allografting peripheral sympathetic ganglia, such as superior cervical ganglia, partially relieves clinical or behavioral deficits in parkinsonian patients and animals. However, removal of these ganglia can cause Homer's syndrome, which limits the utilization of this approach. Hyperhidrosis, a disease of excessive sweating, is commonly seen in young Orientals. Treatment of hyperhidrosis often involves surgical removal of the second thoracic sympathetic ganglia (T2G), which contain catecholaminergic neurons. The purpose of our study was to investigate behavioral responses and tyrosine hydroxylase (TH) immunoreactivity in hemiparkinsonian rats at different time points after transplantation of human T2G from hyperhidrotic patients. Athymic Fisher 344 rats were injected unilaterally with 6-hydroxydopamine into the medial forebrain bundle to destroy the nigrostriatal dopaminergic (DA) pathway. The effectiveness of lesions was tested by measuring methamphetamine (MA)-induced rotations. These unilaterally lesioned rats were later transplanted with T2G or T2 fiber tract (T2F) obtained from adult hyperhidrotic patients. Animals grafted with T2G showed a reduction in MA-induced rotation by 2 weeks; however, rotation returned to the pregrafting levels by 3 months. Animals receiving T2F grafts did not show any reduction of rotation over a 3-month period. Animals were later sacrificed for TH immunostaining at different time points. Tyrosine hydroxylase-positive [TH(+)] cell bodies and fibers were found in the lesioned striatum 2-4 weeks after T2G grafting, suggesting the survival of transplants. Two to 3 months after grafting, TH(+) fibers were still found in almost all the recipients. However, TH(+) cell bodies were found in only three of seven rats studied. Animals receiving T2F grafting did not show any TH immunoreactivity in the lesioned striatum over the 3-month period. These data indicate that T2G transplants from adult hyperhidrotic patients can survive and provide transient normalization of the motor behavior in the hemiparkinsonian athymic rats. Because of the short-term improvement in behavior after grafting, the use of T2G in human trials should be cautious at the present time. Further laboratory research is required.
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Affiliation(s)
- D M Liu
- Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
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Abstract
This 29-year-old man with cerebral palsy complicated by generalized dystonia was treated by simultaneous bilateral posteroventral pallidotomy. Postoperatively, there was slow, but steady, improvement in the patient's dystonia and disability. However, the improvement in abnormal movements was only prominent for cervical dystonia and oromandibular dyskinesia. The patient's Burke-Fahn-Marsden dystonia scores were 51 preoperatively and 37, 33.5 and 33.5, at 3, 6, and 12 months postoperatively, respectively, demonstrating a maximum improvement of 34%. These results suggest that pallidotomy can be an alternative therapy for those patients suffering from intractable generalized dystonia.
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Affiliation(s)
- J J Lin
- Department of Neurology, Chushang Show-Chwan Hospital, Nantou, Taiwan, Republic of China.
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Abstract
BACKGROUND AND PURPOSE Osteogenic protein-1 (OP1) not only possesses trophic activity on bone tissue but also influences neuronal survival and differentiation in vitro. Specific receptors for OP1 are present in brain and spinal cord and can be upregulated during cerebral contusion. OP1 is a member of the transforming growth factor-beta superfamily, several of whose members possess neuroprotective activity. In this study, the neuroprotective effect of OP1 in cerebral ischemia was evaluated in adult animals. METHODS Adult male Sprague-Dawley rats were anesthetized with chloral hydrate. OP1 or vehicle was administered intracortically or intracerebroventricularly to the rats. Thirty minutes, 24 hours, or 72 hours after OP1 injection, the right middle cerebral artery (MCA) was ligated for 90 minutes. Twenty-four hours after reperfusion, animals were tested for motor behavior. The animals were subsequently anesthetized with urethane and perfused intracardially with saline. Brain tissue was removed, sliced, and incubated with 2% triphenyltetrazolium chloride to localize the area of infarction. RESULTS Only animals pretreated with OP1 24 hours before MCA ligation showed a reduction in motor impairment. OP1, given 30 minutes or 72 hours before MCA ligation, did not reduce cortical infarction. In contrast, pretreatment with OP1 24 hours before MCA ligation significantly attenuated the volume of infarction in the cortex, in agreement with the behavioral findings. CONCLUSIONS Intracerebral administration of OP1 24 hours before MCA ligation reduces ischemia-induced injury in the cerebral cortex.
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Affiliation(s)
- S Z Lin
- Department of Pharmacology and Neurosurgery, National Defense Medical Center, Taipei, Taiwan
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Wang YC, Kuo JS, Lin SZ. The effect of trigeminal neurotomy on the alteration of local cerebral blood flow of normotensive and hypertensive rats in acute cold stress. CHINESE J PHYSIOL 1998; 41:167-73. [PMID: 9915129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
The cold season is reported to have the highest incidence of stroke in a year. Cold is usually detected by cold receptors in the face. The present studies were designed to test whether the trigeminal nerve plays a role in the regulation of local cerebral blood flow (LCBF) in animals exposed to a cold environment. Since hypertension affects the incidence of strokes, both Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) were used. Each species was divided into four groups: trigeminal neurotomy (TNx) or control group at room temperature (20 degrees C) or cold environment (5 degrees C), respectively. LCBF in 14 brain structures was measured using the [14C] iodoantipyrine technique and tissue dissecting methods. Our results show that TNx did not alter physiological parameters and LCBFs in WKY and SHR kept either at 20 degrees C or at 5 degrees C for 30 min. However, a transient exposure (30 minutes) to cold caused concomitantly a significant decrease in core body temperature of both WKY and SHR groups (p<0.05, Student's paired t-test) and a significant decrease in LCBFs at the temporal cortex (TC), hypothalamus (HYP) and midbrain (MID) of WKY and TC of SHR (P<0.05, MANOVA). TNx did not alter LCBFs significantly following transient cold exposure in WKY and SHR. Our findings indicate that in the cold environment, the lowered LCBFs in some areas of the brain may relate to the decreased metabolic rate caused by decreased body temperature, and may partly contribute to the higher prevalence of stroke in winter. Our findings also suggest that trigeminal nerve do not exert tonic control of LCBFs and the cold afferents in trigeminal nerve are not important in modulation of the LCBFs.
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Affiliation(s)
- Y C Wang
- Department of Neurosurgery, Taichung Veterans General Hospital, Taiwan, ROC
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Lin JJ, Lin SZ, Lin GY, Chang DC, Lee CC. Application of bilateral sequential pallidotomy to treat a patient with generalized dystonia. Eur Neurol 1998; 40:108-10. [PMID: 9776629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Affiliation(s)
- J J Lin
- Department of Neurology, Chushang Show-Chwan Hospital, Nantou, Taiwan, ROC
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Wang YC, Kuo JS, Lin SZ. The effect of sphenopalatine postganglionic neurotomy on the alteration of local cerebral blood flow of normotensive and hypertensive rats in acute cold stress. Proc Natl Sci Counc Repub China B 1998; 22:122-8. [PMID: 9779601] [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: 02/09/2023]
Abstract
The cold season of a year has been reported to have the highest incidence of strokes. Present studies were designed to test whether the parasympathetic denervation plays any role in the regulation of local cerebral blood flow (LCBF) in anesthetized animals exposed to a cold environment. Each species of Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) was divided into four groups: sphenopalatine postganglionic neurotomy (SPNx) or a control group at room temperature (20 degrees C) or in a cold environment (5 degrees C), respectively. LCBF in 14 brain structures was measured using the [14C] iodoantipyrine technique and tissue dissecting methods. Our results show that SPNx did not significantly alter physiological parameters and LCBF in WKY and SHR kept at either 20 degrees C or 5 degrees C. However, 30 minutes of cold exposure caused a significant decrease in the core body temperature of both the WKY and SHR groups (P < 0.05, Student's paired t-test) and a significant decrease in LCBF in 3 of 14 brain areas: the temporal cortex (TC), inferior colliculus (IC) and vermis (VER) of both WKY and SHR (P < 0.05, MANOVA). The percentages of decrease were 24% (TC), 12% (IC), 12% (VER) and 19% (TC), 16% (IC), 15% (VER), respectively. Our findings indicate that in a cold environment, the lower LCBFs in some areas of the brain may be related to decreased body temperature. Whether they are related to the higher prevalence of stroke in winter needs further investigation.
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Affiliation(s)
- Y C Wang
- Department of Neurosurgery, Taichung Veterans General Hospital, Taiwan, R.O.C
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Glinn M, Ni B, Irwin RP, Kelley SW, Lin SZ, Paul SM. Inorganic Pi increases neuronal survival in the acute early phase following excitotoxic/oxidative insults. J Neurochem 1998; 70:1850-8. [PMID: 9572268 DOI: 10.1046/j.1471-4159.1998.70051850.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [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: 02/07/2023]
Abstract
Inorganic phosphate (Pi) plays a vital role in intracellular energy metabolism. Its many effects include stimulation of glucose use, enhancement of high-energy phosphate concentrations, and modulation of cytosolic free [Ca2+]. Cultured fetal rat cortical neurons constitutively import Pi, and cytosolic levels positively correlate with [ATP], [NADPH], and energy charge. In the present study, we demonstrate that the concentration of intracellular Pi is an important determinant of acute neuronal survival after an excitotoxic or oxidative insult to cultured fetal rat cortical neurons. Extracellular Pi dose-dependently enhanced survival of cortical neurons after exposure to NMDA at early (< or = 6 h) time points after termination of the insult. Pi similarly increased neuronal survival after exposure to kainic acid or H2O2. Pi-exposed neurons had higher basal intracellular [Pi], [ATP], and [GSH], and slightly lower cytosolic free [Ca2+], compared with Pi-deprived neurons. Pi-exposed neurons maintained increased [ATP] after exposure to NMDA and displayed reduced formation of reactive oxygen species after exposure to kainic acid or H2O2, compared with Pi-deprived neurons. These findings demonstrate that changes in extracellular and intracellular Pi can affect neuronal survival after excitotoxic or oxidative insults.
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Affiliation(s)
- M Glinn
- Department of Neuroscience Research, Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USA
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Lin SZ, Yan GM, Koch KE, Paul SM, Irwin RP. Mastoparan-induced apoptosis of cultured cerebellar granule neurons is initiated by calcium release from intracellular stores. Brain Res 1997; 771:184-95. [PMID: 9401738 DOI: 10.1016/s0006-8993(97)00763-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [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: 02/05/2023]
Abstract
We have recently reported that mastoparan, a peptide toxin isolated from wasp venom, induces apoptosis in cultured cerebellar granule neurons that can be blocked by cholera toxin, an activator of Gs. Measurements of intracellular free calcium concentration ([Ca2+]i) reveal that mastoparan induces a dramatic elevation of [Ca2+]i that is frequently followed by enhanced leakage of fura-2 out of the neurons, suggesting that this rise in [Ca2+]i may be due to a more generalized change in membrane permeability. However, the mastoparan-induced initial elevation of [Ca2+]i is maintained in the absence of extracellular Ca2+, suggesting that the rise of [Ca2+]i is from intracellular stores. This conclusion is supported by the observation that depletion of [Ca2+]i stores by pretreatment with either caffeine or thapsigargin attenuates both the rise in [Ca2+]i and cell death induced by mastoparan. Phospholipase C (PLC) inhibitors, neomycin and U73122 block mastoparan-induced increases of [Ca2+]i and protect against neuronal death. Pretreatment with cholera toxin, but not pertussis toxin, reduced the mastoparan-induced rise in [Ca2+]i. Taken together, our data suggest that mastoparan initiates cell death in cerebellar granule neurons by inducing Ca2+ release from intracellular stores, probably via activation of PLC and IP3. A secondary or parallel process results in disruption of plasma membrane integrity and may be ultimately responsible for the death of these neurons by mastoparan.
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Affiliation(s)
- S Z Lin
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis 46202-5120, USA
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Liang SC, Lin SZ, Yu JF, Wu SF, Wang SD, Liu JC. F344-rnu/rnu athymic rats: breeding performance and acceptance of subcutaneous and intracranial xenografts at different ages. Lab Anim Sci 1997; 47:549-53. [PMID: 9355102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- S C Liang
- Department of Surgery, Tri-Service General Hospital, Taipei, Taiwan, Republic of China
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Wang Y, Wang SD, Lin SZ, Chiou AL, Chen LK, Chen JF, Zhou FC. Transplantation of microencapsulated PC12 cells provides long-term improvement of dopaminergic functions. CHINESE J PHYSIOL 1997; 40:121-9. [PMID: 9434887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The purpose of this study is to examine if microencapsulated PC12 cells may provide long term effects to the hemiparkinsonian rats. A modified technique was used to encapsulate PC12 cells into gelled microspheres. We found that the PC12 cells can survive in the modified microcapsules in vitro. Most of the PC12 cells formed cluster 3 weeks after incubation. The PC12 cell-loaded microcapsules were also examined in vitro. Adult Sprague-Dawley rats, anesthetized with chloral hydrate, were injected unilaterally with 6-hydroxydopamine into the medial forebrain bundle. The effectiveness of this lesion was tested by measuring apomorphine or methamphetamine-induced rotation one month after lesioning. The unilaterally lesioned rats were transplanted with microencapsulated PC12 cells. Results showed that apomorphine and methamphetamine-induced rotations were greatly suppressed after transplantation. One year after the grafting, the animals were anesthetized with urethane for the voltammetric study. Low dose of KCl was directly injected into the grafted striatum through pressure microejection. We found that KCl-induced DA release, as measured by voltammetric techniques, was regenerated in the striatum. The animals were later sacrificed for histological examination. We found that capsules were present in the lesioned striatum one year after grafting. Most of the capsules contained no PC12 cell. However, some capsules were filled entirely with PC12 cells. Taken together, our data suggested that PC12 cells can survive in the capsule in vitro and may provide long-term dopaminergic effects to the hemiparkinsonian rats.
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Affiliation(s)
- Y Wang
- Department of Pharmacology, National Defense Medical Center, Taipei, Taiwan, ROC.
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