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Feng et al. Growth cone collapse in adult sensory neurons

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this should have been achieved, a future study could processes after spinal cord injury. J Neurotrauma 2006;23:264-80.
include a secondary enzyme-linked immunosorbent 9. Kaneko S, Iwanami A, Nakamura M, Kishino A, Kikuchi K, Shibata S,
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these four neurotrophic factors work together in a responses and functional recovery of the injured spinal cord. Nat Med
synergistic manner or through individual mechanisms. 2006;12:1380-9.
Similar to previous studies, further experiments where 10. Niclou SP, Ehlert EME, Verhaagen J. Chemorepellent axon guidance
multiple neurotrophic factors are co-inhibited could molecules in spinal cord injury. J Neurotrauma 2006;23:409-21.
shed light on this question. Furthermore, as an animal 11. Pasterkamp RJ, Giger RJ, Ruitenberg MJ, Holtmaat AJ, De Wit
J, De Winter F, Verhaagen J. Expression of the gene encoding the
model, it has limited human application. A future study chemorepellent semaphorin III is induced in the fibroblast component
repeated in a human DRG cell line, using human EG, of neural scar tissue formed following injuries of adult but not neonatal
may provide better translational knowledge. CNS. Mol Cell Neurosci 1999;13:143-66.
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Acknowledgments III is needed for normal patterning and growth of nerves, bones and
We thank Ms. Ann Kolkin for her critical proof reading heart. Nature 1996;383:525-8.
of the manuscript and suggestions for revision. 13. Pasterkamp RJ, Verhaagen J. Semaphorins in axon regeneration:
developmental guidance molecules gone wrong? Philos Trans R Soc
Lond B Biol Sci 2006;361:1499-511.
Financial support and sponsorship 14. Taniguchi M, Yuasa S, Fujisawa H, Naruse I, Saga S, Mishina M, Yagi
The article is supported by Canadian Spinal Research T. Disruption of semaphorin III/D gene causes severe abnormality in
Organization #84831. peripheral nerve projection. Neuron 1997;19:519-30.
15. Jiang SX, Whitehead S, Aylsworth A, Slinn J, Zurakowski B, Chan
Conflicts of interest K, Li J, Hou ST. Neuropilin 1 directly interacts with Fer kinase to
There are no conflicts of interest. mediate semaphorin 3A-induced death of cortical neurons. J Biol Chem
2010;285:9908-18.
Patient consent 16. Reza JN, Gavazzi I, Cohen J. Neuropilin-1 is expressed on adult
No patient involved. mammalian dorsal root ganglion neurons and mediates semaphorin3a/
collapsin-1-induced growth cone collapse by small diameter sensory
afferents. Mol Cell Neurosci 1999;14:317-26.
Ethics approval 17. Tang X-Q, Tanelian DL, Smith GM. Semaphorin3A inhibits nerve
All experiments were performed in accordance with the growth factor-induced sprouting of nociceptive afferents in adult rat
requirements of the Animals for Research Act of Ontario, spinal cord. J Neurosci 2004;24:819-27.
Canada and the Guidelines of the Canadian Council on 18. Wanigasekara Y, Keast JR. Nerve growth factor, glial cell line-derived
Animal Care and were approved by the Animal Research neurotrophic factor and neurturin prevent semaphorin 3A-mediated
Ethics Board at our institution. growth cone collapse in adult sensory neurons. Neuroscience
2006;142:369-79.
19. Treinys R, Kaselis A, Jover E, Bagnard D, Šatkauskas S. R-type calcium
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