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Volumn 185, Issue 3, 2010, Pages 215-226

Phloroglucinol (1,3,5-trihydroxybenzene) protects against ionizing radiation-induced cell damage through inhibition of oxidative stress in vitro and in vivo

Author keywords

Apoptosis; Cell damage; Oxidative stress; Phloroglucinol; Reactive oxygen species; Reduced glutathione

Indexed keywords

CASPASE 3; CASPASE 9; GLUTAMATE CYSTEINE LIGASE; GLUTATHIONE; MITOGEN ACTIVATED PROTEIN KINASE KINASE 4; PHLOROGLUCINOL; PROTEIN BCL 2; REACTIVE OXYGEN METABOLITE; STRESS ACTIVATED PROTEIN KINASE; TRANSCRIPTION FACTOR AP 1; CASPASE; RADIOPROTECTIVE AGENT;

EID: 77952314064     PISSN: 00092797     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.cbi.2010.02.031     Document Type: Article
Times cited : (67)

References (54)
  • 2
    • 0036200121 scopus 로고    scopus 로고
    • Dietary polyunsaturated fatty acids: impact on cancer chemotherapy and radiation
    • Conklin K.A. Dietary polyunsaturated fatty acids: impact on cancer chemotherapy and radiation. Altern. Med. Rev. 2002, 7:4-21.
    • (2002) Altern. Med. Rev. , vol.7 , pp. 4-21
    • Conklin, K.A.1
  • 3
    • 26644437215 scopus 로고    scopus 로고
    • Identification of mammalian proteins cross-linked to DNA by ionizing radiation
    • Barker S., Weinfeld M., Zheng J., Li L., Murray D. Identification of mammalian proteins cross-linked to DNA by ionizing radiation. J. Biol. Chem. 2005, 280:33826-33838.
    • (2005) J. Biol. Chem. , vol.280 , pp. 33826-33838
    • Barker, S.1    Weinfeld, M.2    Zheng, J.3    Li, L.4    Murray, D.5
  • 4
    • 37849004297 scopus 로고    scopus 로고
    • Protective effect of N-acetylcysteine against radiation induced DNA damage and hepatic toxicity in rats
    • Mansour H.H., Hafez H.F., Fahmy N.M., Hanafi N. Protective effect of N-acetylcysteine against radiation induced DNA damage and hepatic toxicity in rats. Biochem. Pharmacol. 2008, 75:773-780.
    • (2008) Biochem. Pharmacol. , vol.75 , pp. 773-780
    • Mansour, H.H.1    Hafez, H.F.2    Fahmy, N.M.3    Hanafi, N.4
  • 5
    • 43049129180 scopus 로고    scopus 로고
    • Effects of N-acetylcysteine amide (NACA), a thiol antioxidant on radiation-induced cytotoxicity in Chinese hamster ovary cells
    • Wu W., Abraham L., Ogony J., Matthews R., Goldstein G., Ercal N. Effects of N-acetylcysteine amide (NACA), a thiol antioxidant on radiation-induced cytotoxicity in Chinese hamster ovary cells. Life Sci. 2008, 82:1122-1130.
    • (2008) Life Sci. , vol.82 , pp. 1122-1130
    • Wu, W.1    Abraham, L.2    Ogony, J.3    Matthews, R.4    Goldstein, G.5    Ercal, N.6
  • 6
    • 0642343129 scopus 로고    scopus 로고
    • Antioxidative properties of brown algae polyphenolics and their perspectives as chemopreventive agents against vascular risk factors
    • Kang K., Park Y., Hwang H.J., Kim S.H., Lee J.G., Shin H.C. Antioxidative properties of brown algae polyphenolics and their perspectives as chemopreventive agents against vascular risk factors. Arch. Pharm. Res. 2003, 26:286-293.
    • (2003) Arch. Pharm. Res. , vol.26 , pp. 286-293
    • Kang, K.1    Park, Y.2    Hwang, H.J.3    Kim, S.H.4    Lee, J.G.5    Shin, H.C.6
  • 7
    • 4644304417 scopus 로고    scopus 로고
    • Inhibitory phlorotannins from the edible brown alga Ecklonia stolonifera on total reactive oxygen species (ROS) generation
    • Kang H.S., Chung H.Y., Kim J.Y., Son B.W., Jung H.A., Choi J.S. Inhibitory phlorotannins from the edible brown alga Ecklonia stolonifera on total reactive oxygen species (ROS) generation. Arch. Pharm. Res. 2004, 27:194-198.
    • (2004) Arch. Pharm. Res. , vol.27 , pp. 194-198
    • Kang, H.S.1    Chung, H.Y.2    Kim, J.Y.3    Son, B.W.4    Jung, H.A.5    Choi, J.S.6
  • 9
    • 40549116687 scopus 로고    scopus 로고
    • Protective effect of phlorotannin components phloroglucinol and eckol on radiation-induced intestinal injury in mice
    • Moon C., Kim S.H., Kim J.C., Hyun J.W., Lee N.H., Park J.W., Shin T. Protective effect of phlorotannin components phloroglucinol and eckol on radiation-induced intestinal injury in mice. Phytother. Res. 2008, 22:238-242.
    • (2008) Phytother. Res. , vol.22 , pp. 238-242
    • Moon, C.1    Kim, S.H.2    Kim, J.C.3    Hyun, J.W.4    Lee, N.H.5    Park, J.W.6    Shin, T.7
  • 12
    • 32044472146 scopus 로고    scopus 로고
    • Alveolar epithelial cells secrete chemokines in response to IL-1beta and lipopolysaccharide but not to ozone
    • Manzer R., Wang J., Nishina K., McConville G., Mason R.J. Alveolar epithelial cells secrete chemokines in response to IL-1beta and lipopolysaccharide but not to ozone. Am. J. Respir. Cell Mol. Biol. 2006, 34:158-166.
    • (2006) Am. J. Respir. Cell Mol. Biol. , vol.34 , pp. 158-166
    • Manzer, R.1    Wang, J.2    Nishina, K.3    McConville, G.4    Mason, R.J.5
  • 13
    • 0036189435 scopus 로고    scopus 로고
    • Macrophage lipoprotein lipase expression is increased in patients with heterozygous familial hypercholesterolemia
    • Beauchamp M.C., Letendre E., Renier G. Macrophage lipoprotein lipase expression is increased in patients with heterozygous familial hypercholesterolemia. J. Lipid Res. 2002, 43:215-222.
    • (2002) J. Lipid Res. , vol.43 , pp. 215-222
    • Beauchamp, M.C.1    Letendre, E.2    Renier, G.3
  • 14
    • 0034595555 scopus 로고    scopus 로고
    • A novel fluorescent probe diphenyl-l-pyrenylphosphine to follow lipid peroxidation in cell membranes
    • Okimoto Y., Watanabe A., Niki E., Yamashita T., Noguchi N. A novel fluorescent probe diphenyl-l-pyrenylphosphine to follow lipid peroxidation in cell membranes. FEBS Lett. 2000, 474:137-140.
    • (2000) FEBS Lett. , vol.474 , pp. 137-140
    • Okimoto, Y.1    Watanabe, A.2    Niki, E.3    Yamashita, T.4    Noguchi, N.5
  • 15
    • 0347924987 scopus 로고    scopus 로고
    • Effect of vinblastine sulfate on gamma-radiation-induced DNA single-strand breaks in murine tissues
    • Rajagopalan R., Ranjan S.K., Nair C.K. Effect of vinblastine sulfate on gamma-radiation-induced DNA single-strand breaks in murine tissues. Mutat. Res. 2003, 536:15-25.
    • (2003) Mutat. Res. , vol.536 , pp. 15-25
    • Rajagopalan, R.1    Ranjan, S.K.2    Nair, C.K.3
  • 16
    • 0034693836 scopus 로고    scopus 로고
    • Microgels for estimation of DNA strand breaks. DNA protein cross links and apoptosis
    • Singh N.P. Microgels for estimation of DNA strand breaks. DNA protein cross links and apoptosis. Mutat. Res. 2000, 455:111-127.
    • (2000) Mutat. Res. , vol.455 , pp. 111-127
    • Singh, N.P.1
  • 17
    • 0023130372 scopus 로고
    • Evaluation of a tetrazolium-based semiautomated colorimetric assay: assessment of chemosensitivity testing
    • Carmichael J., DeGraff W.G., Gazdar A.F., Minna J.D., Mitchell J.B. Evaluation of a tetrazolium-based semiautomated colorimetric assay: assessment of chemosensitivity testing. Cancer Res. 1987, 47:936-941.
    • (1987) Cancer Res. , vol.47 , pp. 936-941
    • Carmichael, J.1    DeGraff, W.G.2    Gazdar, A.F.3    Minna, J.D.4    Mitchell, J.B.5
  • 18
    • 0025726216 scopus 로고
    • A rapid and simple method for measuring thymocyte apoptosis by propidium iodide staining and flow cytometry
    • Nicoletti I., Migliorati G., Pagliacci M.C., Grignani F., Riccardi C. A rapid and simple method for measuring thymocyte apoptosis by propidium iodide staining and flow cytometry. J. Immunol. Methods 1991, 139:271-279.
    • (1991) J. Immunol. Methods , vol.139 , pp. 271-279
    • Nicoletti, I.1    Migliorati, G.2    Pagliacci, M.C.3    Grignani, F.4    Riccardi, C.5
  • 19
    • 39149116749 scopus 로고    scopus 로고
    • Multiparametric analysis of cells with different mitochondrial membrane potential during apoptosis by polychromatic flow cytometry
    • Troiano L., Ferraresi R., Lugli E., Nemes E., Roat E., Nasi M., Pinti M., Cossarizza A. Multiparametric analysis of cells with different mitochondrial membrane potential during apoptosis by polychromatic flow cytometry. Nat. Protoc. 2007, 2:2719-2727.
    • (2007) Nat. Protoc. , vol.2 , pp. 2719-2727
    • Troiano, L.1    Ferraresi, R.2    Lugli, E.3    Nemes, E.4    Roat, E.5    Nasi, M.6    Pinti, M.7    Cossarizza, A.8
  • 20
    • 23244443817 scopus 로고    scopus 로고
    • Evaluation of radioprotective effects of Rajgira (Amaranthus paniculatus) extract in Swiss albino mice
    • Krishna A., Kumar A. Evaluation of radioprotective effects of Rajgira (Amaranthus paniculatus) extract in Swiss albino mice. J. Radiat. Res. 2005, 46:233-239.
    • (2005) J. Radiat. Res. , vol.46 , pp. 233-239
    • Krishna, A.1    Kumar, A.2
  • 22
    • 66749191640 scopus 로고    scopus 로고
    • Overexpression of glutamate-cysteine ligase protects human COV434 granulosa tumour cells against oxidative and {gamma}-radiation-induced cell death
    • Cortes-Wanstreet M.M., Giedzinski E., Limoli C.L., Luderer U. Overexpression of glutamate-cysteine ligase protects human COV434 granulosa tumour cells against oxidative and {gamma}-radiation-induced cell death. Mutagenesis 2009, 24:211-224.
    • (2009) Mutagenesis , vol.24 , pp. 211-224
    • Cortes-Wanstreet, M.M.1    Giedzinski, E.2    Limoli, C.L.3    Luderer, U.4
  • 23
    • 0142250877 scopus 로고    scopus 로고
    • Protective role of alpha-phenyl-N-t-butylnitrone against ionizing radiation in U937 cells and mice
    • Lee J.H., Park J.W. Protective role of alpha-phenyl-N-t-butylnitrone against ionizing radiation in U937 cells and mice. Cancer Res. 2003, 63:6885-6893.
    • (2003) Cancer Res. , vol.63 , pp. 6885-6893
    • Lee, J.H.1    Park, J.W.2
  • 25
    • 33845977959 scopus 로고    scopus 로고
    • Mitochondrial membrane permeabilization in cell death
    • Kroemer G., Galluzzi L., Brenner C. Mitochondrial membrane permeabilization in cell death. Physiol. Rev. 2007, 87:99-163.
    • (2007) Physiol. Rev. , vol.87 , pp. 99-163
    • Kroemer, G.1    Galluzzi, L.2    Brenner, C.3
  • 27
    • 1842610579 scopus 로고    scopus 로고
    • Caspase activation precedes PTP opening in TNF-alpha-induced apoptosis in L929 cells
    • Piret J.P., Arnould T., Fuks B., Chatelain P., Remacle J., Michiels C. Caspase activation precedes PTP opening in TNF-alpha-induced apoptosis in L929 cells. Mitochondrion 2004, 3:261-278.
    • (2004) Mitochondrion , vol.3 , pp. 261-278
    • Piret, J.P.1    Arnould, T.2    Fuks, B.3    Chatelain, P.4    Remacle, J.5    Michiels, C.6
  • 28
    • 0034654517 scopus 로고    scopus 로고
    • The role of Apaf-1, caspase-9, and bid proteins in etoposide- or paclitaxel-induced mitochondrial events during apoptosis
    • Perkins C.L., Fang G., Kim C.N., Bhalla K.N. The role of Apaf-1, caspase-9, and bid proteins in etoposide- or paclitaxel-induced mitochondrial events during apoptosis. Cancer Res. 2000, 60:1645-1653.
    • (2000) Cancer Res. , vol.60 , pp. 1645-1653
    • Perkins, C.L.1    Fang, G.2    Kim, C.N.3    Bhalla, K.N.4
  • 29
    • 48749131954 scopus 로고    scopus 로고
    • Eckol protects V79-4 lung fibroblast cells against gamma-ray radiation-induced apoptosis via the scavenging of reactive oxygen species and inhibiting of the c-Jun NH(2)-terminal kinase pathway
    • Zhang R., Kang K.A., Piao M.J., Ko D.O., Wang Z.H., Lee I.K., Kim B.J., Jeong I.Y., Shin T., Park J.W., Lee N.H., Hyun J.W. Eckol protects V79-4 lung fibroblast cells against gamma-ray radiation-induced apoptosis via the scavenging of reactive oxygen species and inhibiting of the c-Jun NH(2)-terminal kinase pathway. Eur. J. Pharmacol. 2008, 591:114-123.
    • (2008) Eur. J. Pharmacol. , vol.591 , pp. 114-123
    • Zhang, R.1    Kang, K.A.2    Piao, M.J.3    Ko, D.O.4    Wang, Z.H.5    Lee, I.K.6    Kim, B.J.7    Jeong, I.Y.8    Shin, T.9    Park, J.W.10    Lee, N.H.11    Hyun, J.W.12
  • 30
    • 0346435108 scopus 로고    scopus 로고
    • Analysis of interleukin-1 beta-induced cell signaling activation in rat hippocampus following exposure to gamma irradiation. Protective effect of eicosapentaenoic acid
    • Lynch A.M., Moore M., Craig S., Lonergan P.E., Martin D.S., Lynch M.A. Analysis of interleukin-1 beta-induced cell signaling activation in rat hippocampus following exposure to gamma irradiation. Protective effect of eicosapentaenoic acid. J. Biol. Chem. 2003, 278:51075-51084.
    • (2003) J. Biol. Chem. , vol.278 , pp. 51075-51084
    • Lynch, A.M.1    Moore, M.2    Craig, S.3    Lonergan, P.E.4    Martin, D.S.5    Lynch, M.A.6
  • 31
    • 0037036429 scopus 로고    scopus 로고
    • Neuroprotective effect of eicosapentaenoic acid in hippocampus of rats exposed to gamma-irradiation
    • Lonergan P.E., Martin D.S., Horrobin D.F., Lynch M.A. Neuroprotective effect of eicosapentaenoic acid in hippocampus of rats exposed to gamma-irradiation. J. Biol. Chem. 2002, 277:20804-20811.
    • (2002) J. Biol. Chem. , vol.277 , pp. 20804-20811
    • Lonergan, P.E.1    Martin, D.S.2    Horrobin, D.F.3    Lynch, M.A.4
  • 33
  • 35
    • 3242688111 scopus 로고    scopus 로고
    • Augmentation of wound healing by ascorbic acid treatment in mice exposed to gamma-radiation
    • Jagetia G.C., Rajanikant G.K., Baliga M.S., Rao K.V., Kumar P. Augmentation of wound healing by ascorbic acid treatment in mice exposed to gamma-radiation. Int. J. Radiat. Biol. 2004, 80:347-354.
    • (2004) Int. J. Radiat. Biol. , vol.80 , pp. 347-354
    • Jagetia, G.C.1    Rajanikant, G.K.2    Baliga, M.S.3    Rao, K.V.4    Kumar, P.5
  • 36
    • 0141541809 scopus 로고    scopus 로고
    • Generation of reactive oxygen species and radiation response in lymphocytes and tumor cells
    • Bhavani S., Kumar S.S., Sainis K.B. Generation of reactive oxygen species and radiation response in lymphocytes and tumor cells. Radiat. Res. 2003, 160:150-159.
    • (2003) Radiat. Res. , vol.160 , pp. 150-159
    • Bhavani, S.1    Kumar, S.S.2    Sainis, K.B.3
  • 37
    • 0024161399 scopus 로고
    • Detection and repair of DNA base damages produced by ionizing radiation
    • Wallace S.S. Detection and repair of DNA base damages produced by ionizing radiation. Environ. Mol. Mutagen. 1988, 12:431-477.
    • (1988) Environ. Mol. Mutagen. , vol.12 , pp. 431-477
    • Wallace, S.S.1
  • 38
    • 0027375157 scopus 로고
    • Direct enzymic detection of endogenous oxidative base damage in human lymphocyte DNA
    • Collins A.R., Duthie S.J., Dobson V.L. Direct enzymic detection of endogenous oxidative base damage in human lymphocyte DNA. Carcinogenesis 1993, 14:1733-1735.
    • (1993) Carcinogenesis , vol.14 , pp. 1733-1735
    • Collins, A.R.1    Duthie, S.J.2    Dobson, V.L.3
  • 39
    • 0033884625 scopus 로고    scopus 로고
    • Antioxidant properties of Asparagus racemosus against damage induced by gamma-radiation in rat liver mitochondria
    • Kamat J.P., Boloor K.K., Devasagayam T.P., Venkatachalam S.R. Antioxidant properties of Asparagus racemosus against damage induced by gamma-radiation in rat liver mitochondria. J. Ethnopharmacol. 2000, 71:425-435.
    • (2000) J. Ethnopharmacol. , vol.71 , pp. 425-435
    • Kamat, J.P.1    Boloor, K.K.2    Devasagayam, T.P.3    Venkatachalam, S.R.4
  • 40
    • 0023872970 scopus 로고
    • The bacterial mutagenicity of synthetic all-trans fecapentaene-12 changes when assayed under anaerobic conditions
    • Venitt S., Bosworth D. The bacterial mutagenicity of synthetic all-trans fecapentaene-12 changes when assayed under anaerobic conditions. Mutagenesis 1988, 3:169-173.
    • (1988) Mutagenesis , vol.3 , pp. 169-173
    • Venitt, S.1    Bosworth, D.2
  • 41
    • 0021758865 scopus 로고
    • Site-specific cleavage of double-strand DNA by hydroperoxide of linoleic acid
    • Inouye S. Site-specific cleavage of double-strand DNA by hydroperoxide of linoleic acid. FEBS Lett. 1984, 172:231-234.
    • (1984) FEBS Lett. , vol.172 , pp. 231-234
    • Inouye, S.1
  • 42
    • 0041402784 scopus 로고    scopus 로고
    • Radioprotective effects of 2-iminothiazolidine derivatives against lethal doses of gamma radiation in mice
    • Hosseinimehr S.J., Shafiee A., Mozdarani H., Akhlagpour S. Radioprotective effects of 2-iminothiazolidine derivatives against lethal doses of gamma radiation in mice. J. Radiat. Res. 2001, 42:401-408.
    • (2001) J. Radiat. Res. , vol.42 , pp. 401-408
    • Hosseinimehr, S.J.1    Shafiee, A.2    Mozdarani, H.3    Akhlagpour, S.4
  • 43
    • 33845626962 scopus 로고    scopus 로고
    • Glutathione protects cells against arsenite-induced toxicity
    • Habib G.M., Shi Z.Z., Lieberman M.W. Glutathione protects cells against arsenite-induced toxicity. Free Radic. Biol. Med. 2007, 42:191-201.
    • (2007) Free Radic. Biol. Med. , vol.42 , pp. 191-201
    • Habib, G.M.1    Shi, Z.Z.2    Lieberman, M.W.3
  • 44
    • 0142042895 scopus 로고    scopus 로고
    • Fish tolerance to organophosphate-induced oxidative stress is dependent on the glutathione metabolism and enhanced by N-acetylcysteine
    • Pena-Llopis S., Ferrando M.D., Pena J.B. Fish tolerance to organophosphate-induced oxidative stress is dependent on the glutathione metabolism and enhanced by N-acetylcysteine. Aquat. Toxicol. 2003, 65:337-360.
    • (2003) Aquat. Toxicol. , vol.65 , pp. 337-360
    • Pena-Llopis, S.1    Ferrando, M.D.2    Pena, J.B.3
  • 46
    • 0025302401 scopus 로고
    • Role of glutathione in the radiation response of mammalian cells in vitro and in vivo
    • Bump E.A., Brown J.M. Role of glutathione in the radiation response of mammalian cells in vitro and in vivo. Pharmacol. Ther. 1990, 47:117-136.
    • (1990) Pharmacol. Ther. , vol.47 , pp. 117-136
    • Bump, E.A.1    Brown, J.M.2
  • 47
    • 42449089421 scopus 로고    scopus 로고
    • Epigallocatechin-3-gallate inhibits growth of activated hepatic stellate cells by enhancing the capacity of glutathione synthesis
    • Fu Y., Zheng S., Lu S.C., Chen A. Epigallocatechin-3-gallate inhibits growth of activated hepatic stellate cells by enhancing the capacity of glutathione synthesis. Mol. Pharmacol. 2008, 73:1465-1473.
    • (2008) Mol. Pharmacol. , vol.73 , pp. 1465-1473
    • Fu, Y.1    Zheng, S.2    Lu, S.C.3    Chen, A.4
  • 48
    • 0035795180 scopus 로고    scopus 로고
    • Generation and propagation of radical reactions on proteins
    • Hawkins C.L., Davies M.J. Generation and propagation of radical reactions on proteins. Biochim. Biophys. Acta 2001, 1504:196-219.
    • (2001) Biochim. Biophys. Acta , vol.1504 , pp. 196-219
    • Hawkins, C.L.1    Davies, M.J.2
  • 50
    • 0036690648 scopus 로고    scopus 로고
    • PS-341, a novel proteasome inhibitor, induces Bcl-2 phosphorylation and cleavage in association with G2-M phase arrest and apoptosis
    • Ling Y.H., Liebes L., Ng B., Buckley M., Elliott P.J., Adams J., Jiang J.D., Muggia F.M., Perez-Soler R. PS-341, a novel proteasome inhibitor, induces Bcl-2 phosphorylation and cleavage in association with G2-M phase arrest and apoptosis. Mol. Cancer Ther. 2002, 1:841-849.
    • (2002) Mol. Cancer Ther. , vol.1 , pp. 841-849
    • Ling, Y.H.1    Liebes, L.2    Ng, B.3    Buckley, M.4    Elliott, P.J.5    Adams, J.6    Jiang, J.D.7    Muggia, F.M.8    Perez-Soler, R.9
  • 53
    • 41149172493 scopus 로고    scopus 로고
    • Immunomodulatory and radioprotective effects of lignans derived from fresh nutmeg mace (Myristica fragrans) in mammalian splenocytes
    • Checker R., Chatterjee S., Sharma D., Gupta S., Variyar P., Sharma A., Poduval T.B. Immunomodulatory and radioprotective effects of lignans derived from fresh nutmeg mace (Myristica fragrans) in mammalian splenocytes. Int. Immunopharmacol. 2008, 8:661-669.
    • (2008) Int. Immunopharmacol. , vol.8 , pp. 661-669
    • Checker, R.1    Chatterjee, S.2    Sharma, D.3    Gupta, S.4    Variyar, P.5    Sharma, A.6    Poduval, T.B.7
  • 54
    • 0032992167 scopus 로고    scopus 로고
    • Inhibition of radiation-induced DNA damage in plasmid pBR322 by chlorophyllin and possible mechanism(s) of action
    • Kumar S.S., Chaubey R.C., Devasagayam T.P., Priyadarsini K.I., Chauhan P.S. Inhibition of radiation-induced DNA damage in plasmid pBR322 by chlorophyllin and possible mechanism(s) of action. Mutat. Res. 1999, 425:71-79.
    • (1999) Mutat. Res. , vol.425 , pp. 71-79
    • Kumar, S.S.1    Chaubey, R.C.2    Devasagayam, T.P.3    Priyadarsini, K.I.4    Chauhan, P.S.5


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