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Volumn 150, Issue 4, 2008, Pages 395-403

Effect of anoxia on the electroretinogram of three anoxia-tolerant vertebrates

Author keywords

Adenosine; ERG; Hemiscyllium ocellatum; Rana pipiens; Trachemys scripta

Indexed keywords

8 CYCLOPENTYLTHEOPHYLLINE; ADENOSINE; ADENOSINE A1 RECEPTOR; ADENOSINE A1 RECEPTOR ANTAGONIST; ADENOSINE TRIPHOSPHATE; AMINOPHYLLINE; OXYGEN;

EID: 45849129387     PISSN: 10956433     EISSN: 15314332     Source Type: Journal    
DOI: 10.1016/j.cbpa.2008.03.022     Document Type: Article
Times cited : (18)

References (59)
  • 1
    • 0021955360 scopus 로고
    • Temporal transfer and nonlinearity properties of turtle ERG - tuning by temperature, pharmacology, and light intensity
    • Adolph A.R. Temporal transfer and nonlinearity properties of turtle ERG - tuning by temperature, pharmacology, and light intensity. Vision Res. 25 (1985) 483-492
    • (1985) Vision Res. , vol.25 , pp. 483-492
    • Adolph, A.R.1
  • 2
    • 33745027153 scopus 로고    scopus 로고
    • Modulation of visual inputs to accessory optic system by theophylline during hypoxia
    • Ariel M. Modulation of visual inputs to accessory optic system by theophylline during hypoxia. Exp. Brain Res. 172 (2006) 351-360
    • (2006) Exp. Brain Res. , vol.172 , pp. 351-360
    • Ariel, M.1
  • 3
    • 0027066844 scopus 로고
    • Cerebral anoxia tolerance in turtles - regulation of intracellular calcium and pH
    • Bickler P.E. Cerebral anoxia tolerance in turtles - regulation of intracellular calcium and pH. Am. J. Physiol. 263 (1992) R1298-R1302
    • (1992) Am. J. Physiol. , vol.263
    • Bickler, P.E.1
  • 4
    • 0034657111 scopus 로고    scopus 로고
    • Hypoxia-induced silencing of NMDA receptors in turtle neurons
    • Bickler P.E., Donohoe P.H., and Buck L.T. Hypoxia-induced silencing of NMDA receptors in turtle neurons. J. Neurosci. 20 (2000) 3522-3528
    • (2000) J. Neurosci. , vol.20 , pp. 3522-3528
    • Bickler, P.E.1    Donohoe, P.H.2    Buck, L.T.3
  • 5
    • 0026686696 scopus 로고
    • Retinal ischemia induced by occlusion of both common carotid arteries in rats as demonstrated by electroretinography
    • Block F., Schwarz M., and Sontag K.H. Retinal ischemia induced by occlusion of both common carotid arteries in rats as demonstrated by electroretinography. Neurosci. Lett. 144 (1992) 124-126
    • (1992) Neurosci. Lett. , vol.144 , pp. 124-126
    • Block, F.1    Schwarz, M.2    Sontag, K.H.3
  • 6
    • 0014296155 scopus 로고
    • Electroretinogram - its components and their origins
    • Brown K.T. Electroretinogram - its components and their origins. Vis. Res. 8 (1968) 633-677
    • (1968) Vis. Res. , vol.8 , pp. 633-677
    • Brown, K.T.1
  • 7
    • 0031885299 scopus 로고    scopus 로고
    • Adenosine and anoxia reduce N-methyl-d-aspartate receptor open probability in turtle cerebrocortex
    • Buck L.T., and Bickler P.E. Adenosine and anoxia reduce N-methyl-d-aspartate receptor open probability in turtle cerebrocortex. J. Exp. Biol. 201 (1998) 289-297
    • (1998) J. Exp. Biol. , vol.201 , pp. 289-297
    • Buck, L.T.1    Bickler, P.E.2
  • 8
    • 0024270725 scopus 로고
    • Anatomy and physiology of visual evoked potentials and electroretinograms
    • Celesia G.G. Anatomy and physiology of visual evoked potentials and electroretinograms. Neurol. Clin. 6 (1988) 657-679
    • (1988) Neurol. Clin. , vol.6 , pp. 657-679
    • Celesia, G.G.1
  • 9
    • 0033779945 scopus 로고    scopus 로고
    • Effects of hypoxemia on the a- and b-waves of the electroretinogram in the cat retina
    • Derwent J., and Linsenmeier R. Effects of hypoxemia on the a- and b-waves of the electroretinogram in the cat retina. Invest. Ophthalmol. Vis. Sci. 41 (2000) 3634-3642
    • (2000) Invest. Ophthalmol. Vis. Sci. , vol.41 , pp. 3634-3642
    • Derwent, J.1    Linsenmeier, R.2
  • 10
    • 0035738182 scopus 로고    scopus 로고
    • Hypoglycemia increases the sensitivity of the cat electroretinogram to hypoxemia
    • Derwent J.J.K., and Linsenmeier R.A. Hypoglycemia increases the sensitivity of the cat electroretinogram to hypoxemia. Vis. Neurosci. 18 (2001) 983-993
    • (2001) Vis. Neurosci. , vol.18 , pp. 983-993
    • Derwent, J.J.K.1    Linsenmeier, R.A.2
  • 11
    • 12944267620 scopus 로고    scopus 로고
    • The protective effects of metabolic rate depression in hypoxic cold submerged frogs
    • Donohoe P.H., and Boutilier R.G. The protective effects of metabolic rate depression in hypoxic cold submerged frogs. Res. Physiol. 111 (1998) 325-336
    • (1998) Res. Physiol. , vol.111 , pp. 325-336
    • Donohoe, P.H.1    Boutilier, R.G.2
  • 12
    • 34247266718 scopus 로고    scopus 로고
    • The heart as a working model to explore themes and strategies for anoxic survival in ectothermic vertebrates
    • Farrell A.P., and Stecyk J.A.W. The heart as a working model to explore themes and strategies for anoxic survival in ectothermic vertebrates. Comp. Biochem. Physiol., A 147 (2007) 300-312
    • (2007) Comp. Biochem. Physiol., A , vol.147 , pp. 300-312
    • Farrell, A.P.1    Stecyk, J.A.W.2
  • 14
    • 0026578506 scopus 로고
    • Similarity of the effects of hypoxia and l-glutamate on the electroretinogram
    • Hankins M.W., and Ikeda H. Similarity of the effects of hypoxia and l-glutamate on the electroretinogram. Clin. Vis. Sci. 7 (1992) 77-82
    • (1992) Clin. Vis. Sci. , vol.7 , pp. 77-82
    • Hankins, M.W.1    Ikeda, H.2
  • 15
    • 0022590628 scopus 로고
    • Defense strategies against hypoxia and hypothermia
    • Hochachka P.W. Defense strategies against hypoxia and hypothermia. Science 231 (1986) 234-241
    • (1986) Science , vol.231 , pp. 234-241
    • Hochachka, P.W.1
  • 16
    • 0027935498 scopus 로고
    • Time-course of anoxia induced increase in cerebral bloodflow rate in turtles - evidence for a role of adenosine
    • Hylland P., Nilsson G.E., and Lutz P.L. Time-course of anoxia induced increase in cerebral bloodflow rate in turtles - evidence for a role of adenosine. J. Cereb. Blood Flow Metab. 14 (1994) 877-881
    • (1994) J. Cereb. Blood Flow Metab. , vol.14 , pp. 877-881
    • Hylland, P.1    Nilsson, G.E.2    Lutz, P.L.3
  • 17
    • 0028970625 scopus 로고
    • Recovery of photopic ERG from pressure induced retinal ischemia in rabbit eyes
    • Imai M., and Iijima H. Recovery of photopic ERG from pressure induced retinal ischemia in rabbit eyes. Jpn. J. Ophthalmol. 39 (1995) 254-259
    • (1995) Jpn. J. Ophthalmol. , vol.39 , pp. 254-259
    • Imai, M.1    Iijima, H.2
  • 18
    • 0029198834 scopus 로고
    • Roles of energy status, K-ATP channels and channel arrest in fish brain K+ gradient dissipation during anoxia
    • Johansson D., and Nilsson G.E. Roles of energy status, K-ATP channels and channel arrest in fish brain K+ gradient dissipation during anoxia. J. Exp. Biol. 198 (1995) 2575-2580
    • (1995) J. Exp. Biol. , vol.198 , pp. 2575-2580
    • Johansson, D.1    Nilsson, G.E.2
  • 19
    • 0031450207 scopus 로고    scopus 로고
    • Anoxic depression of light-evoked potentials in retina and optic tectum of crucian carp
    • Johansson D., Nilsson G.E., and Doving K.B. Anoxic depression of light-evoked potentials in retina and optic tectum of crucian carp. Neurosci. Lett. 237 (1997) 73-76
    • (1997) Neurosci. Lett. , vol.237 , pp. 73-76
    • Johansson, D.1    Nilsson, G.E.2    Doving, K.B.3
  • 20
    • 8844261836 scopus 로고    scopus 로고
    • Neuroepithelial oxygen chemoreceptors of the zebrafish gill
    • Jonz M.G., Fearon I.M., and Nurse C.A. Neuroepithelial oxygen chemoreceptors of the zebrafish gill. J. Physiol. London 560 (2004) 737-752
    • (2004) J. Physiol. London , vol.560 , pp. 737-752
    • Jonz, M.G.1    Fearon, I.M.2    Nurse, C.A.3
  • 21
    • 0035745939 scopus 로고    scopus 로고
    • Slow ATP loss and the defense of ion homeostasis in the anoxic frog brain
    • Knickerbocker D.L., and Lutz P.L. Slow ATP loss and the defense of ion homeostasis in the anoxic frog brain. J. Exp. Biol. 204 (2001) 3547-3551
    • (2001) J. Exp. Biol. , vol.204 , pp. 3547-3551
    • Knickerbocker, D.L.1    Lutz, P.L.2
  • 22
    • 0030444626 scopus 로고    scopus 로고
    • Involvement of adenosine in retinal ischemia - studies on the rat
    • Larsen A.K., and Osborne N.N. Involvement of adenosine in retinal ischemia - studies on the rat. Invest. Ophthalmol. Vis. Sci. 37 (1996) 2603-2611
    • (1996) Invest. Ophthalmol. Vis. Sci. , vol.37 , pp. 2603-2611
    • Larsen, A.K.1    Osborne, N.N.2
  • 23
    • 0030909558 scopus 로고    scopus 로고
    • Contrasting strategies for anoxic brain survival-glycolysis up or down
    • Lutz P.L., and Nilsson G.E. Contrasting strategies for anoxic brain survival-glycolysis up or down. J. Exp. Biol. 200 (1997) 411-419
    • (1997) J. Exp. Biol. , vol.200 , pp. 411-419
    • Lutz, P.L.1    Nilsson, G.E.2
  • 24
    • 0031280222 scopus 로고    scopus 로고
    • Survival of energy failure in the anoxic frog brain: delayed release of glutamate
    • Lutz P.L., and Reiners R. Survival of energy failure in the anoxic frog brain: delayed release of glutamate. J. Exp. Biol. 200 (1997) 2913-2917
    • (1997) J. Exp. Biol. , vol.200 , pp. 2913-2917
    • Lutz, P.L.1    Reiners, R.2
  • 25
    • 4644234016 scopus 로고    scopus 로고
    • Negotiating brain anoxia survival in the turtle
    • Lutz P.L., and Milton S.L. Negotiating brain anoxia survival in the turtle. J. Exp. Biol. 207 (2004) 3141-3147
    • (2004) J. Exp. Biol. , vol.207 , pp. 3141-3147
    • Lutz, P.L.1    Milton, S.L.2
  • 26
  • 27
    • 0022371813 scopus 로고
    • Living without oxygen - turtle brain as a model of anaerobic metabolism
    • Lutz P.L., Rosenthal M., and Sick T.J. Living without oxygen - turtle brain as a model of anaerobic metabolism. Mol. Physiol. 8 (1985) 411-425
    • (1985) Mol. Physiol. , vol.8 , pp. 411-425
    • Lutz, P.L.1    Rosenthal, M.2    Sick, T.J.3
  • 29
    • 0037235610 scopus 로고    scopus 로고
    • Multiple effects of adenosine in the arterially perfused mammalian eye. Possible mechanisms for the neuroprotective function of adenosine in the retina - adenosine in the perfused eye
    • Macaluso C., Frishman L.J., Frueh B., Kaelin-Lang A., Onoe S., and Niemeyer G. Multiple effects of adenosine in the arterially perfused mammalian eye. Possible mechanisms for the neuroprotective function of adenosine in the retina - adenosine in the perfused eye. Doc. Ophthalmol. 106 (2003) 51-59
    • (2003) Doc. Ophthalmol. , vol.106 , pp. 51-59
    • Macaluso, C.1    Frishman, L.J.2    Frueh, B.3    Kaelin-Lang, A.4    Onoe, S.5    Niemeyer, G.6
  • 30
    • 18644376713 scopus 로고    scopus 로고
    • The next generation of phosphodiesterase inhibitors: structural clues to ligand and substrate selectivity of phosphodiesterases
    • Manallack D.T., Hughes R.A., and Thompson P.E. The next generation of phosphodiesterase inhibitors: structural clues to ligand and substrate selectivity of phosphodiesterases. J. Med. Chem. 48 (2005) 3449-3462
    • (2005) J. Med. Chem. , vol.48 , pp. 3449-3462
    • Manallack, D.T.1    Hughes, R.A.2    Thompson, P.E.3
  • 32
    • 0014780064 scopus 로고
    • Intracellular responses of Muller (glial) cells of mudpuppy retina - their relation to B-wave of electroretinogram
    • Miller R.F., and Dowling J.E. Intracellular responses of Muller (glial) cells of mudpuppy retina - their relation to B-wave of electroretinogram. J. Neurophysiol. 33 (1970) 323-341
    • (1970) J. Neurophysiol. , vol.33 , pp. 323-341
    • Miller, R.F.1    Dowling, J.E.2
  • 33
    • 0036081385 scopus 로고    scopus 로고
    • Mechanisms for maintaining extracellular glutamate levels in the anoxic turtle striatum
    • Milton S.L., Thompson J.W., and Lutz P.L. Mechanisms for maintaining extracellular glutamate levels in the anoxic turtle striatum. Am. J. Physiol. 282 (2002) R1317-1323
    • (2002) Am. J. Physiol. , vol.282
    • Milton, S.L.1    Thompson, J.W.2    Lutz, P.L.3
  • 34
    • 0344584519 scopus 로고    scopus 로고
    • Slow death in the leopard frog Rana pipiens: neurotransmitters and anoxia tolerance
    • Milton S.L., Manuel L., and Lutz P.L. Slow death in the leopard frog Rana pipiens: neurotransmitters and anoxia tolerance. J. Exp. Biol. 206 (2003) 4021-4028
    • (2003) J. Exp. Biol. , vol.206 , pp. 4021-4028
    • Milton, S.L.1    Manuel, L.2    Lutz, P.L.3
  • 35
    • 0036906021 scopus 로고    scopus 로고
    • Effect of body temperature on electroretinogram of mice
    • Mizota A., and Adachi-Usami E. Effect of body temperature on electroretinogram of mice. Invest. Ophthalmol. Vis. Sci. 43 (2002) 3754-3757
    • (2002) Invest. Ophthalmol. Vis. Sci. , vol.43 , pp. 3754-3757
    • Mizota, A.1    Adachi-Usami, E.2
  • 36
    • 0034683228 scopus 로고    scopus 로고
    • Neuronal oxidative hypometabolism in the brainstem of the epaulette shark (Hemiscyllium ocellatum) in response to hypoxic pre-conditioning
    • Mulvey J.M., and Renshaw G.M.C. Neuronal oxidative hypometabolism in the brainstem of the epaulette shark (Hemiscyllium ocellatum) in response to hypoxic pre-conditioning. Neurosci. Lett. 290 (2000) 1-4
    • (2000) Neurosci. Lett. , vol.290 , pp. 1-4
    • Mulvey, J.M.1    Renshaw, G.M.C.2
  • 37
    • 0016709147 scopus 로고
    • Function of retina in perfused eye
    • Niemeyer G. Function of retina in perfused eye. Doc. Ophthalmol. 39 (1975) 53-116
    • (1975) Doc. Ophthalmol. , vol.39 , pp. 53-116
    • Niemeyer, G.1
  • 38
    • 0035489396 scopus 로고    scopus 로고
    • Surviving anoxia with the brain turned on
    • Nilsson G.E. Surviving anoxia with the brain turned on. News Physiol. Sci. 16 (2001) 217-221
    • (2001) News Physiol. Sci. , vol.16 , pp. 217-221
    • Nilsson, G.E.1
  • 39
    • 33746316480 scopus 로고    scopus 로고
    • From basic to clinical research: a journey with the retina, the retinal pigment epithelium, the cornea, age-related macular degeneration and hereditary degenerations, as seen in the rear view mirror
    • Nilsson S.E.G. From basic to clinical research: a journey with the retina, the retinal pigment epithelium, the cornea, age-related macular degeneration and hereditary degenerations, as seen in the rear view mirror. Acta Ophthalmol. Scan. 84 (2006) 452-465
    • (2006) Acta Ophthalmol. Scan. , vol.84 , pp. 452-465
    • Nilsson, S.E.G.1
  • 40
    • 0000032107 scopus 로고
    • Adenosine release in the anoxic turtle brain - a possible mechanism for anoxic survival
    • Nilsson G.E., and Lutz P.L. Adenosine release in the anoxic turtle brain - a possible mechanism for anoxic survival. J. Exp. Biol. 162 (1992) 345-351
    • (1992) J. Exp. Biol. , vol.162 , pp. 345-351
    • Nilsson, G.E.1    Lutz, P.L.2
  • 42
    • 4644324293 scopus 로고    scopus 로고
    • Hypoxic survival strategies in two fishes: extreme anoxia tolerance in the North European crucian carp and natural hypoxic preconditioning in a coral-reef shark
    • Nilsson G.E., and Renshaw G.M.C. Hypoxic survival strategies in two fishes: extreme anoxia tolerance in the North European crucian carp and natural hypoxic preconditioning in a coral-reef shark. J. Exp. Biol. 207 (2004) 3131-3139
    • (2004) J. Exp. Biol. , vol.207 , pp. 3131-3139
    • Nilsson, G.E.1    Renshaw, G.M.C.2
  • 43
    • 0000254878 scopus 로고
    • Anoxic depression of spontaneous locomotor activity in crucian carp quantified by a computerized imaging technique
    • Nilsson G.E., Rosen P., and Johansson D. Anoxic depression of spontaneous locomotor activity in crucian carp quantified by a computerized imaging technique. J. Exp. Biol. 180 (1993) 153-162
    • (1993) J. Exp. Biol. , vol.180 , pp. 153-162
    • Nilsson, G.E.1    Rosen, P.2    Johansson, D.3
  • 45
    • 0032415122 scopus 로고    scopus 로고
    • ATP-sensitive K+ channel activation provides transient protection to the anoxic turtle brain
    • Pek-Scott M., and Lutz P.L. ATP-sensitive K+ channel activation provides transient protection to the anoxic turtle brain. Am. J. Physiol. 44 (1998) R2023-R2027
    • (1998) Am. J. Physiol. , vol.44
    • Pek-Scott, M.1    Lutz, P.L.2
  • 46
    • 0026518612 scopus 로고
    • Downregulation of sodium channels during anoxia - a putative survival strategy of turtle brain
    • Perez-Pinzon M.A., Rosenthal M., Sick T.J., Lutz P.L., Pablo J., and Mash D. Downregulation of sodium channels during anoxia - a putative survival strategy of turtle brain. Am. J. Physiol. 262 (1992) R712-R715
    • (1992) Am. J. Physiol. , vol.262
    • Perez-Pinzon, M.A.1    Rosenthal, M.2    Sick, T.J.3    Lutz, P.L.4    Pablo, J.5    Mash, D.6
  • 47
    • 0036159220 scopus 로고    scopus 로고
    • The role of adenosine in the anoxic survival of the epaulette shark, Hemiscyllium ocellatum
    • Renshaw G.M.C., Kerrisk C.B., and Nilsson G.E. The role of adenosine in the anoxic survival of the epaulette shark, Hemiscyllium ocellatum. Comp. Biochem. Physiol., B 131 (2002) 133-141
    • (2002) Comp. Biochem. Physiol., B , vol.131 , pp. 133-141
    • Renshaw, G.M.C.1    Kerrisk, C.B.2    Nilsson, G.E.3
  • 49
    • 0036164080 scopus 로고    scopus 로고
    • Exposure to hypoxia primes the respiratory and metabolic responses of the epaulette shark to progressive hypoxia
    • Routley M.H., Nilsson G.E., and Renshaw G.M.C. Exposure to hypoxia primes the respiratory and metabolic responses of the epaulette shark to progressive hypoxia. Comp. Biochem. Physiol., A 131 (2002) 313-321
    • (2002) Comp. Biochem. Physiol., A , vol.131 , pp. 313-321
    • Routley, M.H.1    Nilsson, G.E.2    Renshaw, G.M.C.3
  • 50
    • 0022555320 scopus 로고
    • The influence of phosphodiesterase inhibitors on Erg and optic-nerve response of the cat
    • Schneider T., and Zrenner E. The influence of phosphodiesterase inhibitors on Erg and optic-nerve response of the cat. Invest. Ophthalmol. Vis. Sci. 27 (1986) 1395-1403
    • (1986) Invest. Ophthalmol. Vis. Sci. , vol.27 , pp. 1395-1403
    • Schneider, T.1    Zrenner, E.2
  • 52
    • 34249796373 scopus 로고    scopus 로고
    • Adenosine does not save the heart of anoxia-tolerant vertebrates during prolonged oxygen deprivation
    • Stecyk J.A.W., Stenslokken K.O., Nilsson G.E., and Farrell A.P. Adenosine does not save the heart of anoxia-tolerant vertebrates during prolonged oxygen deprivation. Comp. Biochem. Physiol., A 147 (2007) 961-973
    • (2007) Comp. Biochem. Physiol., A , vol.147 , pp. 961-973
    • Stecyk, J.A.W.1    Stenslokken, K.O.2    Nilsson, G.E.3    Farrell, A.P.4
  • 53
    • 0014949212 scopus 로고
    • Intracellular responses to light from cat pigment epithelium - origin of electroretinogram C-wave
    • Steinber R.H., Schmidt R., and Brown K.T. Intracellular responses to light from cat pigment epithelium - origin of electroretinogram C-wave. Nature 227 (1970) 728-730
    • (1970) Nature , vol.227 , pp. 728-730
    • Steinber, R.H.1    Schmidt, R.2    Brown, K.T.3
  • 54
    • 11444266051 scopus 로고    scopus 로고
    • Adenosinergic and cholinergic control mechanisms during hypoxia in the epaulette shark (Hemiscyllium ocellatum), with emphasis on branchial circulation
    • Stenslokken K.O., Sundin L., Renshaw G.M., and Nilsson G.E. Adenosinergic and cholinergic control mechanisms during hypoxia in the epaulette shark (Hemiscyllium ocellatum), with emphasis on branchial circulation. J. Exp. Biol. 207 (2004) 4451-4461
    • (2004) J. Exp. Biol. , vol.207 , pp. 4451-4461
    • Stenslokken, K.O.1    Sundin, L.2    Renshaw, G.M.3    Nilsson, G.E.4
  • 55
    • 33748695778 scopus 로고    scopus 로고
    • ON- and OFF-response of the photopic electroretinogram in relation to stimulus characteristics
    • Sustar M., Hawlina M., and Brecelj J. ON- and OFF-response of the photopic electroretinogram in relation to stimulus characteristics. Doc. Ophthalmol. 113 (2006) 43-52
    • (2006) Doc. Ophthalmol. , vol.113 , pp. 43-52
    • Sustar, M.1    Hawlina, M.2    Brecelj, J.3
  • 58
    • 33746216346 scopus 로고    scopus 로고
    • The ecology of overwintering among turtles: where turtles overwinter and its consequences
    • Ultsch G.R. The ecology of overwintering among turtles: where turtles overwinter and its consequences. Biol. Rev. 81 (2006) 339-367
    • (2006) Biol. Rev. , vol.81 , pp. 339-367
    • Ultsch, G.R.1
  • 59
    • 0000163480 scopus 로고
    • Simultaneous direct and indirect calorimetry on normoxic and anoxic goldfish
    • Van Waversveld J., Addink A.D.F., and Van den Thillart G. Simultaneous direct and indirect calorimetry on normoxic and anoxic goldfish. J. Exp. Biol. 142 (1989) 325-335
    • (1989) J. Exp. Biol. , vol.142 , pp. 325-335
    • Van Waversveld, J.1    Addink, A.D.F.2    Van den Thillart, G.3


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