201
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Tsujimoto T, Ando N, Oyabu H, Uyama H, Kobayashi S. Laccase‐Catalyzed Curing of Natural Phenolic Lipids and Product Properties. JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 2007. [DOI: 10.1080/10601320701424503] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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202
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Abstract
Flavonoids, one of the most numerous and best studied groups of plant polyphenols, are well known to exhibit various biological and pharmacological effects. Functional artificial polymeric flavonoids, flavonoid polymers and amine containing polymer-flavonoid conjugates have been developed. The acid-catalyzed polymerization of catechin and aldehydes proceeds regioselectively to produce catechin-aldehyde polycondensates. Peroxidases and laccases catalyze the oxidative coupling of flavonoids and oxidative conjugation with polyamines. The resulting polymers show much higher antioxidant activities than the flavonoid monomers. In addition, these polymeric flavonoids efficiently inhibit disease related enzymes, such as xanthine oxidase, collagenase, elastase, hyaluronidase and tyrosinase. Based on these results, the molecular design for amplification of the biological and pharmacological properties of flavonoids is proposed.
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203
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Watanabe E, Tomoshige N, Uyama H. New Biodegradable and Thermoresponsive Polymers Based on Amphiphilic Poly(asparagine) Derivatives. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/masy.200750428] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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204
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Chueh SK, Tachibana Y, Uyama H, Kobayashi S, Tomita N. Evaluation of chondrocytes expression embedded in thermoresponsive poly(amino acid)s with sol-gel transition. Biomed Mater Eng 2007; 17:137-46. [PMID: 17502690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Poly(N-substituted alpha/beta-asparagine) was evaluated as a thermoresponsible and an injectable scaffold for cartilage regeneration. Solutions of this polymer are liquid state below 25 degrees C and nonfluid hydrogel above 35 degrees C, allowing an aqueous solution containing cells at room temperature to form a hydrogel with encapsulated cells at physiological body temperature. Chondrocytes were isolated from joint of 4-week-old Japanese white rabbits, dispersed within the thermoresponsive polymer solution and maintained for up to 72 hours in vitro. The polymer solutions demonstrated concentration-dependent inhibitory effect on chondrocytes multiplication. After the three-day cultivation, the survival rate of the chondrocytes fell into a 70~90% ranges among all the tested polymer concentrations. The morphology studies showed that there were some physical and/or chemical stress leading cells to necrosis and some extent apoptosis. Some physical and/or chemical stress may be applied, and over 70% of the chondrocytes could survive through the stress, suggesting that some phenotype could have been selected from the heterogeneous mixture of chondrocytes.
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205
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Moon YS, Uyama H, Inoue S, Tabata Y. Fabrication of Non-woven Mats of Gelatin/Poly(L-lactic acid) Composites by Electrospinning and Their Application for Scaffold of Cell Proliferation. CHEM LETT 2006. [DOI: 10.1246/cl.2006.564] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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206
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207
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Li J, Fukuoka T, He Y, Uyama H, Kobayashi S, Inoue Y. Thermal behavior and phase morphology of miscible hydrogen-bonded blends of poly(ε-caprolactone) and enzymatically polymerized polyphenol. J Appl Polym Sci 2006. [DOI: 10.1002/app.23153] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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208
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Kim E, Uyama H, Doi Y, Ha CS, Iwata T. Crystal structure and morphology of poly(16-hexadecalactone) chain-folded lamellar crystals. Macromol Biosci 2005; 5:734-42. [PMID: 16080167 DOI: 10.1002/mabi.200500038] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Solution-grown, chain-folded lamellar crystals of poly(16-hexadecalactone) (PHDL) were crystallized isothermally from 1-hexanol at 70 degrees C. The morphology of lozenge-shaped crystals was studied by TEM and AFM. The lamellae are ca. 10 nm thick and the chains run orthogonal to the lamellar surface with folding along (110) and (110) planes. The crystal structure of PHDL was determined by XRD and election diffraction of single crystals. The chains are in the 2(1) helix conformation close to all-trans and the structure consists of an orthorhombic unit cell with a P2(1)2(1)2(1) space group with the lattice constants a = 0.746 +/- 0.001 nm, b = 0.504 +/- 0.001 nm, and c (chain axis) = 4.116 +/- 0.003 nm. There are two chains per unit cell, which exist in an antiparallel arrangement. Molecular packing structure has been studied in detail, taking into account both diffraction data and energy calculations. The setting angles, with respect to a axis, were +/-40 degrees for the corner and center chains, respectively. By using the electron and XRD data, the best molecular packing model was refined to R-factors of 0.168 and 0.196, respectively. A brief comparison of chain-packing structure is also made with related polymer structures.
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209
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Xu P, Uyama H, Whitten JE, Kobayashi S, Kaplan DL. Peroxidase-catalyzed in situ polymerization of surface orientated caffeic acid. J Am Chem Soc 2005; 127:11745-53. [PMID: 16104752 DOI: 10.1021/ja051637r] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nanoscale surface patterning and polymerization of caffeic acid on 4-aminothiophenol-functionalized gold surfaces has been demonstrated with dip pen nanolithography (DPN). The diphenolic moiety of caffeic acid can be polymerized by biocatalysis with laccase or horseradish peroxidase. In the present study, the DPN patterned features were polymerized in situ through the use of the peroxidase. Using samples prepared by DPN, microcontact printing, and adsorption on macroscopic substrates, the products were characterized by electrostatic force microscopy (EFM), MALDI-TOF, X-ray photoelectron spectroscopy (XPS), UV-vis, and FT-IR. The in situ surface polymerization resulted in the formation of a quinone structure, while the phenyl ester formed in bulk polymerization reactions was not detected. A different coupling site was observed when comparing the polymers obtained from solution (bulk) vs the surface DPN reactions. The structural differences were attributed to surface-induced pre-organization and orientation of the monomers prior to the enzymatic polymerization step. The results of this study expand the application of DPN technology to surface modification and surface chemistry reactions wherein stereo-regularity and regioselectivity can be exploited.
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210
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Kim YJ, Uyama H. Tyrosinase inhibitors from natural and synthetic sources: structure, inhibition mechanism and perspective for the future. Cell Mol Life Sci 2005; 62:1707-23. [PMID: 15968468 PMCID: PMC11139184 DOI: 10.1007/s00018-005-5054-y] [Citation(s) in RCA: 611] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Tyrosinase is known to be a key enzyme in melanin biosynthesis, involved in determining the color of mammalian skin and hair. Various dermatological disorders, such as melasma, age spots and sites of actinic damage, arise from the accumulation of an excessive level of epidermal pigmentation. In addition, unfavorable enzymatic browning of plant-derived foods by tyrosinase causes a decrease in nutritional quality and economic loss of food products. The inadequacy of current conventional techniques to prevent tyrosinase action encourages us to seek new potent tyrosinase inhibitors. This article overviews the various inhibitors obtained from natural and synthetic sources with their industrial importance.
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211
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Kurisawa M, Chung JE, Yang YY, Gao SJ, Uyama H. Injectable biodegradable hydrogels composed of hyaluronic acid–tyramine conjugates for drug delivery and tissue engineering. Chem Commun (Camb) 2005:4312-4. [PMID: 16113732 DOI: 10.1039/b506989k] [Citation(s) in RCA: 336] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The sequential injection of hyaluronic acid-tyramine conjugates and enzymes forms biodegradable hydrogels in vivo by enzyme-induced oxidative coupling, offering high potential as a promising biomaterial for drug delivery and tissue engineering.
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212
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Takeuchi Y, Uyama H, Tomoshige N, Watanabe E, Tachibana Y, Kobayashi S. Injectable thermoreversible hydrogels based on amphiphilic poly(amino acid)s. ACTA ACUST UNITED AC 2005. [DOI: 10.1002/pola.21189] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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213
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Li J, Fukuoka T, He Y, Uyama H, Kobayashi S, Inoue Y. Thermal and crystallization behavior of hydrogen-bonded miscible blend of poly(3-hydroxybutyrate) and enzymatically polymerized polyphenol. J Appl Polym Sci 2005. [DOI: 10.1002/app.22004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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214
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Kim E, Uyama H, Doi Y, Ha CS, Iwata T. Crystal Structure and Morphology of Poly(12-dodecalactone). Biomacromolecules 2004; 6:572-9. [PMID: 15762615 DOI: 10.1021/bm0494747] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Poly(12-dodecalactone) (PDDL) crystals in the form of chain-folded lamellae were prepared by isothermal crystallization from a 1-hexanol solution. The lozenge-shaped crystals with and without spiral growth have been studied by transmission electron microscopy and atomic force microscopy. Wide-angle X-ray diffraction data, obtained from PDDL lamellae sedimented to form oriented mats and annealed solvent-cast film, were supplemented with morphological and structural data from electron microscopy. PDDL crystallizes as an orthorhombic form with a P2(1)2(1)2(1) space group and lattice constants of a = 0.746 +/- 0.001 nm, b = 0.500 +/- 0.001 nm, and c (chain axis) = 3.281 +/- 0.003 nm. There are two chains per unit cell, which existed in an antiparallel arrangement. The fiber repeat distance is appropriate for an all-trans backbone conformation for the straight stems. Molecular packing of this structure has been studied in detail, taking into account both diffraction data and energy calculations. The setting angles, with respect to the a axis, were +/-43 degrees for the corner and center chains according to intensity measurements and structure factor calculations. The optimized shift along the crystallographic c axis is 0.1c (0.328 nm). A final model was obtained to yield R = 0.180 with X-ray diffraction data and R = 0.162 with electron diffraction data. A brief comparison is also made with related polymer structures.
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215
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Kim YJ, Uyama H, Kobayashi S. Enzymatic Template Polymerization of Phenol in the Presence of Water-soluble Polymers in an Aqueous Medium. Polym J 2004. [DOI: 10.1295/polymj.36.992] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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216
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Kim YJ, Chung JE, Kurisawa M, Uyama H, Kobayashi S. Superoxide anion scavenging and xanthine oxidase inhibition of (+)-catechin-aldehyde polycondensates. Amplification of the antioxidant property of (+)-catechin by polycondensation with aldehydes. Biomacromolecules 2004; 5:547-52. [PMID: 15003019 DOI: 10.1021/bm034392o] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In this study, the antioxidant property of (+)-catechin-aldehyde polycondensates has been examined. Superoxide anions are one of the most typical reactive oxygen species (ROS) and generated by xanthine oxidase (XO). The measurements of the superoxide anion scavenging and XO inhibition activity showed that catechin had pro-oxidant properties in lower concentrations and little XO inhibition. On the other hand, the polycondensates exhibited much higher effects compared to the catechin monomer, and their physiological activities were greatly affected by the structure of polycondensates. Steady-state analysis of the inhibition against XO showed that the inhibition type of the polycondensate was uncompetitive. Furthermore, the results of the circular dichroism and UV-visible measurements of a mixture of the polycondensate and XO were in good agreement with that of the steady-state analysis; the spectral changes due to the chelation of the polycondensate onto the Fe/S and/or the FAD center of XO were observed. These data strongly suggest that the polycondensates possess a great potential as antioxidant for various applications.
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217
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Chung JE, Kurisawa M, Kim YJ, Uyama H, Kobayashi S. Amplification of antioxidant activity of catechin by polycondensation with acetaldehyde. Biomacromolecules 2004; 5:113-8. [PMID: 14715016 DOI: 10.1021/bm0342436] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Catechin exhibits numerous biological and pharmacological effects attributed to antioxidant action. The synthetic poly(catechin)s condensed through acetaldehyde with different molecular weights were assessed in terms of antioxidant activity and enzyme inhibitory activity on the basis of a catechin repeating unit and compared with monomeric catechin. The poly(catechin)s showed great amplification of superoxide scavenging activity, xanthine oxidase (XO) inhibitory activity, and inhibition effects on human low-density lipoprotein oxidation initiated by 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH) as a radical generator on the catechin unit level, compared to monomeric catechin: these activities were proportional to their molecular weights. The reducing power of the polymer was lower than that of monomeric catechin, which decreased with increasing the molecular weight. The polymer also protected endothelial cells from oxidative injury induced by AAPH, with a greater effect expressed on a catechin unit basis than that of the monomer. These results demonstrate that the poly(catechin)s are more potent antioxidant agents and enzyme inhibitors.
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218
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Fukuoka T, Uyama H, Kobayashi S. Synthesis of Poly(amino acid)−Polyphenol Hybrids by Oxidative Cross-Coupling. Macromolecules 2004. [DOI: 10.1021/ma048897y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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219
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Tonami H, Uyama H, Kobayashi S. Oxidative Cross-Coupling between Phenolic Polymer and Phenol-Containing Cellulose: Synthesis of a New Class of Artificial Wood Polymers. Macromolecules 2004. [DOI: 10.1021/ma049420p] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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220
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Choi HS, Ooya T, Sasaki S, Yui N, Kurisawa M, Uyama H, Kobayashi S. Spontaneous Change of Physical State from Hydrogels to Crystalline Precipitates during Poly-pseudorotaxane Formation. Chemphyschem 2004; 5:1431-4. [PMID: 15499862 DOI: 10.1002/cphc.200400172] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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221
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Choi HS, Ooya T, Lee SC, Sasaki S, Kurisawa M, Uyama H, Yui N. pH Dependence of Polypseudorotaxane Formation between Cationic Linear Polyethylenimine and Cyclodextrins. Macromolecules 2004. [DOI: 10.1021/ma049215+] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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222
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Kim E, Uyama H, Doi Y, Ha CS, Iwata T. Crystal Structure and Morphology of Poly(11-undecalactone) Solution-Grown Single Crystals. Macromolecules 2004. [DOI: 10.1021/ma0492871] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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223
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Ihara N, Schmitz S, Kurisawa M, Chung JE, Uyama H, Kobayashi S. Amplification of Inhibitory Activity of Catechin against Disease-Related Enzymes by Conjugation on Poly(ε-lysine). Biomacromolecules 2004; 5:1633-6. [PMID: 15360266 DOI: 10.1021/bm049823x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new inhibitor against disease-related enzymes, collagenase, hyaluronidase, and xanthine oxidase, has been developed by the laccase-catalyzed conjugation of catechin on poly(epsilon-lysine). The resulting poly(epsilon-lysine)-catechin conjugate showed greatly improved inhibition effects on activity of these enzymes, whereas the catechin monomer showed very low inhibition activity. The kinetic analysis on the inhibition of collagenase exhibited that the conjugate was a mixed-type inhibitor. The amplified activities might offer high potential as a therapeutic agent for prevention of various enzyme-related diseases.
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224
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Mita N, Tawaki SI, Uyama H, Kobayashi S. Precise Structure Control of Enzymatically Synthesized Polyphenols. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2004. [DOI: 10.1246/bcsj.77.1523] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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225
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Fukuoka T, Uyama H, Kobayashi S. Effect of Phenolic Monomer Structure of Precursor Polymers in Oxidative Coupling of Enzymatically Synthesized Polyphenols. Macromolecules 2004. [DOI: 10.1021/ma035991q] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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