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Gordon T. Plant - One of the best experts on this subject based on the ideXlab platform.
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Conclusive Evidence for Human Transneuronal Retrograde Degeneration in the Visual System
Journal of Clinical & Experimental Ophthalmology, 2011Co-Authors: Holly Bridge, Gordon T. PlantAbstract:For several decades there was controversy concerning the existence of transneuronal Retrograde Degeneration in the human visual system in spite of a substantial body of data indicating this Degeneration in certain species of nonhuman primate. Over the past few years, however, compelling evidence both from human magnetic resonance imaging and optical coherence tomography has shown conclusively transneuronal Retrograde Degeneration in both the white matter of the optic tract and in the ganglion cells of the retina. In this review the evidence for primate Degeneration and Degeneration in non-visual human neural systems are discussed before the presentation of the recent human data.
Toru Hayakawa - One of the best experts on this subject based on the ideXlab platform.
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Recombinant basic fibroblast growth factor spares thalamic neurons from Retrograde Degeneration after ablation of the somatosensory cortex in rats.
Restorative neurology and neuroscience, 1994Co-Authors: Eiji Kohmura, Takamichi Yuguchi, Kazuo Yamada, Tateo Sakaguchi, Toru HayakawaAbstract:Retrograde Degeneration of thalamic neurons after cortical ablation has long been recognized. Neuronal loss following axotomy eliminates the possibility of regeneration and might prevent the recovery from axonal injury in patients with brain trauma. We investigated whether CS23, a stable recombinant variant of human basic fibroblast growth factor (bFGF), could protect neurons from Retrograde Degeneration. Four weeks after ablation of the somatosensory cortex in young female rats, there was extensive neuronal Degeneration and loss in the lateral ventro-posterior nucleus (VPL) of the ipsilateral thalamus. When Gelfoam soaked in bFGF(CS23) (1 μg/0.l ml) was applied topically at the time of surgery, this neuronal Degeneration in the VPL was markedly reduced and macroscopic atrophy of the lateral and medial ventroposterior nucleus (VPL + VPM) was significantly reduced. In contrast, application of bFGF at three days after surgery failed to prevent Retrograde Degeneration. These resuts indicate that bFGF can prevent thalamic atrophy after ablation of the somatosensory cortex and that administration of bFGF is only effective in the very early period after brain injury.
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Basic Fibroblast Growth Factor Prevents Retrograde Degeneration of the Thalamic Neurons After Ablation of the Somatosensory Cortex
Recent Advances in Neurotraumatology, 1993Co-Authors: Eiji Kohmura, Takamichi Yuguchi, Kazuo Yamada, Takeo Sakaguchi, Toru HayakawaAbstract:We studied whether a recombinant human basic fibroblast growth fac±or (bFGF), could prevent Retrograde Degeneration after neuronal injury. Four weeks after ablation of the somatosensory cortex of young female rats, extensive neuronal Degeneration of the lateral ventroposterior nucleus (VPL) of the ipsilateral thalamus could be observed. When bFGF (Iμg/0.1ml) soaked in gelfoam was applied topically at the time of surgery, this neuronal Degeneration in the VPL was markedly reduced. However, the same dose of bFGF failed to save the thalamic neurons from Retrograde Degeneration, when it was given 3 days later. Cellular response to bFGF was analyzed with BrdU incorporation.
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Detection and partial purification of ischaemia-related neurotrophic activity in the periinfarcted brain tissue.
Neurological research, 1992Co-Authors: Kazuo Yamada, Eiji Kohmura, Tateo Sakaguchi, Akira Kinoshita, Kuzuo Kataoka, Mamoru Taneda, Ryotaro Kuroda, Toru HayakawaAbstract:AbstractIn the rat model of middle cerebral artery (MCA) occlusion, axons originating from the ipsilateral cortical and thalamic neurons are injured by ischaemia. The cortical neurons survive thereafter without Retrograde Degeneration, but thalamic neurons slowly die because of Retrograde Degeneration. The fate of these two neurons is remarkably different and may be related to neurotrophic activity induced by ischaemia. We detected ischaemia-related neurotrophic activity, and partially purified the factor. Tissue samples were obtained from the cortex adjacent to the infarction and contralateral corresponding site at 4, 8 and 12 days after occlusion of the MCA. They were homogenated with a culture medium and ultracentrifuged. The supernatant was obtained and used for neurotrophic assay. Foetal cortical neurons were obtained from 17 days rat embryo and cultured. Neurotrophic activity was assayed by applying tissue extract to the culture medium. Application of periischaemic cortical extract obtained at 8 and...
P Jindahra - One of the best experts on this subject based on the ideXlab platform.
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P.12 The time course of trans-synaptic Retrograde Degeneration following occipital lobe damage
Journal of Neurology Neurosurgery & Psychiatry, 2011Co-Authors: G Plant, P JindahraAbstract:The objective of the study is to quantify the rate of trans-synaptic Retrograde Degeneration (TSRD) following post-chiasmal damage. We have shown previously that TSRD can be detected in the retina by using optical coherence tomography (OCT) and in the optic tract using MRI. Method (1) 38 patients were recruited following acute unilateral damage to the post-geniculate visual pathway (onset 0.016–67 years prior to testing) together with age and sex matched controls. Peri-papillary retinal nerve fibre layer (RNFL) thickness was measured with OCT on a single occasion. (2) 7 cases with homonymous hemianopia and 4 cases with smaller visual field defects were recruited within 4 months of the stroke (range 5–112 days). In this group the RNFL thickness was measured serially for at least 172 days (range 172–917 days). Linear regression was used in the statistical analysis. Results (1) There is a negative correlation between the RNFL thickness and log time since onset of injury (n=38, r=0.54; p Conclusion The time course of TSRD can be followed by utilising OCT.
Alan Cowey - One of the best experts on this subject based on the ideXlab platform.
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Transneuronal Retrograde Degeneration of retinal ganglion cells and optic tract in hemianopic monkeys and humans.
Brain : a journal of neurology, 2011Co-Authors: Alan Cowey, Iona Alexander, Petra StoerigAbstract:Transneuronal Retrograde Degeneration of retinal ganglion cells after removal of primary visual cortex (area V1) is well established by quantitative neurohistological analysis of the ganglion cell layer in monkeys, but remains controversial in human patients. Therefore, we first histologically examined retinal Degeneration in sectioned archived retinae of 26 macaque monkeys with unilateral V1 ablation and post-surgical survival times ranging from 3 months to 14.3 years. In addition, the cross-sectional area of the optic tract was measured in archived coronal histological sections of the brain of every hemianopic monkey and in sections from 10 control monkeys with non-visual bilateral cortical lesions. The ratios of nasal and temporal retinal ganglion cell counts in the contralesional eye and ipsi/contralateral optic tract areas were calculated and compared. They show that the decline was initially more pronounced for the optic tract, slackened after 3 years post-lesion and was steeper for the ganglion cells thereafter. Nevertheless, both measures were highly correlated. Second, we calculated ratios from structural magnetic resonance images to see whether the optic tracts of four human hemianopes would show similar evidence of transneuronal Degeneration of their ipsilesional optic tract. The results were consistent with extensive and time-dependent Degeneration of the retinal ganglion cell layer. The measures of the optic tracts provide evidence for comparable transneuronal retinal ganglion cell Degeneration in both primate species and show that structural magnetic resonance image can both reveal and assess it.
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Transneuronal Retrograde Degeneration of retinal ganglion cells following restricted lesions of striate cortex in the monkey.
Experimental brain research, 2000Co-Authors: Helen L. Johnson, Alan CoweyAbstract:Transneuronal Retrograde Degeneration of retinal ganglion cells follows extensive striate cortical removal in macaque monkeys. Its extent depends on the age of the monkey at operation, post-operative survival, species and retinal eccentricity. Some studies of human patients with occipital lobe injury have found no evidence for transneuronal Retrograde Degeneration, suggesting that either Degeneration may not occur or, if present, it is caused directly by secondary damage impinging upon the underlying white matter or the blood supply to the dorsal lateral geniculate nucleus and optic tract. We therefore studied retinal ganglion cell Degeneration in three macaques in which only the striate cortex corresponding to the macular retina had been removed, thereby sparing extrastriate cortex and precluding interruption of the vascular supply to the thalamus and optic tract. There was extensive loss of ganglion cells in the central retina, corresponding to the central 10° of vision. As the cortical lesion was too small to affect the thalamus or optic tract directly, the retinal Degeneration must be transneuronal. Quantitative analysis showed a 65–80% loss of ganglion cells in the corresponding perifoveal retinae along the horizontal meridian. The results confirm that the loss of retinal ganglion cells following striate cortical lesions is predominantly transneuronal.
Holly Bridge - One of the best experts on this subject based on the ideXlab platform.
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Conclusive Evidence for Human Transneuronal Retrograde Degeneration in the Visual System
Journal of Clinical & Experimental Ophthalmology, 2011Co-Authors: Holly Bridge, Gordon T. PlantAbstract:For several decades there was controversy concerning the existence of transneuronal Retrograde Degeneration in the human visual system in spite of a substantial body of data indicating this Degeneration in certain species of nonhuman primate. Over the past few years, however, compelling evidence both from human magnetic resonance imaging and optical coherence tomography has shown conclusively transneuronal Retrograde Degeneration in both the white matter of the optic tract and in the ganglion cells of the retina. In this review the evidence for primate Degeneration and Degeneration in non-visual human neural systems are discussed before the presentation of the recent human data.