Tesi: "Retinal ganglion cells"

1

Grumet, Andrew Eli. "Extracellular electrical stimulation of retinal ganglion cells". Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/42559.

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2

Davenport, Christopher M. "Neural circuitry of retinal receptive fields in primate /". Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/10652.

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3

Uzzell, Valerie Joy. "Sensitivity and noise in primate retinal ganglion cells /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2005. http://wwwlib.umi.com/cr/ucsd/fullcit?p3190165.

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4

Fok, Lai-chun. "Neuroprotection of retinal ganglion cells with laser therapy". Click to view the E-thesis via HKUTO, 1999. http://sunzi.lib.hku.hk/hkuto/record/B31969616.

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5

Fok, Lai-chun, e 霍麗珍. "Neuroprotection of retinal ganglion cells with laser therapy". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31969616.

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6

Mellough, Carla Bernadette. "An assessment of the cell replacement capability of immortalised, clonal and primary neural tissues following their intravitreal transplantation into rodent models of selective retinal ganglion cell depletion". University of Western Australia. School of Anatomy and Human Biology, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0101.

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Abstract (sommario):

[Truncated abstract] Microenvironmental changes associated with apoptotic neural degeneration may instruct a proportion of newly transplanted donor cells to differentiate towards the fate of the deteriorating host cellular phenotype. In the work described in this thesis, this hypothesis was tested by inducing apoptotic retinal ganglion cell (RGC) death in neonatal and adult rats and mice, and then examining whether intravitreally grafted cells from a range of sources of donor neural tissue became incorporated into these selectively depleted retinae. Donor tissues were: a postnatal murine cerebellar-derived immortalised neural precursor cell line (C17.2); an adult rat hippocampal-derived clonal stem-like line (HCN/GFP); mouse embryonic day 14 (E14) primary dissociated retinal cells (Gt[ROSA]26); and adult mouse ciliary pigmented margin-derived primary neurospheres (Gt[ROSA]26). In neonates, rapid RGC death was induced by removal of the contralateral superior colliculus (SC), and in adults, delayed RGC death was induced by unilateral optic nerve (ON) transection. Some adult hosts received ON transection coupled with an autologous peripheral nerve (PN) graft. Donor cells were injected intravitreally 6-48 h after SC ablation (neonates) or 0, 5, 7 or 14 days after ON injury (adults). Cells were also injected into non-RGC depleted neonatal and adult retinae. At 4 or 8 weeks, transplanted cells were identified, quantified and their differentiation fate within host retinae was assessed. Transplanted male C17.2 cells were identified in host retinae using a Y-chromosome marker and in situ hybridisation, or by their expression of the lacZ reporter gene product Escherichia coli beta-galactosidase (beta-gal) using Xgal histochemistry or a beta-gal antibody. No C17.2 cells were identified in axotomised adult-injected eyes undergoing delayed RGC apoptosis (n = 16). Donor cells were, however, stably integrated within the retina in 29% (15/55) of mice that received C17.2 cell injections 24 h after neonatal SC ablation; 6-31% of surviving cells were found in the RGC layer (GCL). These NSC-like cells were also present in intact retinae, but on average there were fewer cells in GCL. In SC-ablated mice, most grafted cells did not express retinal-specific markers, although occasional donor cells in the GCL were immunopositive for beta-III tubulin (TUJ1), a protein highly iii expressed by, but not specific to, developing RGCs. Targeted rapid RGC depletion thus increased C17.2 cell incorporation into the GCL, but grafted C17.2 cells did not appear to differentiate into an RGC phenotype.

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7

Li, Suk-yee. "Functional changes and differential cell death of retinal ganglion cells after injury". View the Table of Contents & Abstract, 2007. http://sunzi.lib.hku.hk/hkuto/record/B37552612.

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8

Li, Suk-yee, e 李淑儀. "Functional changes and differential cell death of retinal ganglion cells after injury". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38597731.

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9

Lau, Hoi-shan Flora. "Retinal ganglion cells vulnerability in a rat glaucoma model /". View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31495217.

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10

Lau, Hoi-shan Flora, e 劉凱珊. "Retinal ganglion cells vulnerability in a rat glaucoma model". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B45010250.

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11

Menzler, Jacob. "Discharge patterns of retinal ganglion cells in rodent models of degenerative retinal diseases". Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-151112.

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12

Stanke, Jennifer J. "Beyond Neuronal Replacement: Embryonic Retinal Cells Protect Mature Retinal Neurons". The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250820277.

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13

Göritz, Christian. "Influence of glial cells on postnatal differentiation of rat retinal ganglion cells". [S.l. : s.n.], 2005. http://www.diss.fu-berlin.de/2005/65/index.html.

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14

Göritz, Christian. "Influence of glial cells on postnatal differentiation of rat retinal ganglion cells". Université Louis Pasteur (Strasbourg) (1971-2008), 2005. https://publication-theses.unistra.fr/public/theses_doctorat/2005/GORITZ_Christian_2005.pdf.

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15

Icha, Jaroslav. "Ganglion cell translocation across the retina and its importance for retinal lamination". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-218914.

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Correct layering (lamination) of neurons in the central nervous system (CNS) is critical for the tissue functionality. Neuronal lamination is established during development, when the majority of neurons have to move from their birthplace to the appropriate layer, where they function. Therefore, to grasp the logic of CNS development, it is essential to understand the kinetics and modes of the variety of neuronal translocation events. Most of our knowledge about neuronal translocation has been gained using fixed tissue or ex vivo imaging, which is not ideal for such a dynamic process heavily dependent on the surrounding environment. To avoid these limitations, I combined translucent zebrafish embryos with light sheet fluorescence microscopy, which together enabled gentle in toto imaging of neuronal translocation. I studied the translocation of retinal ganglion cells (RGCs) across the developing zebrafish retina. RGCs are the first neurons that differentiate in the vertebrate retina and are born in a proliferative zone at the retinal apical side. From here, they move basally, spanning the complete apico-basal length of the tissue. They are destined to occupy the most basal layer, where their axons form the optic nerve. Although it was described that RGCs move their soma while being attached to both apical and basal sides of the retina, the kinetics and cell biological mechanisms of somal translocation remained unknown. Extracting single cell behavior of RGCs from high-resolution movies of their translocation allowed for quantitative analysis of RGC movement. I revealed that RGCs cross the retina in less than two hours in a directionally persistent manner. The movement of RGC soma is a cell autonomously generated process, which requires intact microtubules and actin-dependent basal attachment of cells for speed and efficiency. Unexpectedly, interference with somal translocation leads to a shift towards a multipolar migratory mode, previously not observed for RGCs, in which they temporarily lose both apical and basal attachment and apico-basal polarity. The multipolar mode is overall slower and less directionally persistent, but still allows RGCs to reach the basal retina. However, when RGC translocation is inhibited completely, they differentiate ectopically in the center of the retina, which in turn triggers the formation of ectopic layers of later born neurons. These results highlight the importance of establishing the basal layer of ganglion cells for ensuing retinal lamination. Overall, I generated important advances in the understanding of neuronal translocation and lamination, which might be relevant for other parts of the CNS.

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16

Chandra, Ashleigh Jessica. "Characterisation of Ganglion Cells in Human and Non-Human Primate Retinas". Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/19121.

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Background: Ganglion cells are the output neurons of the retina, sending visual signals from the eye to the brain. In total 17 types of retinal ganglion cell have been identified, but only a low number is well characterized. This is because reliable markers for less well characterized, “wide-field” ganglion cell types are hard to come by. Antibodies against calcium binding proteins have been recognized as markers for specific neurons in the retina. Here, immunohistochemistry and intracellular injections were used to identify and characterise the calretinin and calbindin expressing cell types in the ganglion cell layer of human and non-human primate retinas. The main focus of this study is to investigate some of the low density ganglion cell types in human and marmoset retinas. This is a significant cause for investigation because dysfunction in ganglion cells can cause irreversible blindness. Therefore, the more that is known about these important cells, and what methods can be used to study them, the more can be contributed to future clinical research into treatable blinding diseases. Aim: To characterise low-density ganglion cell types in the retina. Hypothesis: Calcium binding proteins calretinin and calbindin are markers for sub-populations of retinal ganglion cells. Chapter 1 introduces the anatomical and morphological characteristics of retinal neurons in human and non-human primates. Chapter 2 investigates the use of antibodies against calretinin to characterise cells in the ganglion cell layer of marmoset monkey retina. Retinas were fixed, cut into quadrants and sectioned vertically using a vibratome, or processed as whole mounts. Double labelling was performed using antibodies against calretinin and RBPMS (RNA binding protein with multiple splicing, expressed in ganglion cell bodies). The proportion of calretinin positive cells were quantified. Cells from additional retinas were pre-labelled and intracellularly injected with dye to analysetheir morphology. The dendritic field size, soma size stratification and eccentricity of the cells were measured and compared with previous data. The majority of calretinin positive ganglion cells were characterised into narrow thorny and broad thorny ganglion cell types. Chapter 3 investigates the use of antibodies against calbindin to characterise cells in the ganglion cell layer of human retina. Retinas were fixed, cut and processed as sections or whole mounts with antibodies as described in the previous chapter, including double and triple labelling using antibodies against calbindin, RBPMS, melanopsin and ChAT (choline\ acetyl transferase, expressed in starburst amacrine cells). Additional retinas were again pre labelled and intracellularly injected with dye and cells were morphologically analysed. It was found that calbindin positive cells have large dendritic fields and a morphology corresponding to intrinsically photosensitive melanopsin-expressing ganglion cells. Double labelling confirmed melanopsin-expressing cells are calbindin positive. Chapter 4 explores the implications of these findings for future research into the use of calcium binding proteins as markers for subpopulations of less well characterised ganglion cell types.

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17

Qiao, Mu. "Morphological, Physiological and Molecular Classification of Mouse Retinal Ganglion Cells". Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:26718723.

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Visual information is conveyed from the retina to the brain through axons of retinal ganglion cells (RGCs). There are >20 different subtypes of RGCs, each of which detects specific features. Classification of RGC subtypes is thus essential for us to understand how visual information is processed and delivered to the brain. Here I reported my efforts in classifying different subtypes of RGCs, using morphological, physiological and molecular criteria. A combination of these criteria allowed me to successfully identify subtypes from alpha RGCs, Foxp2-positive RGCs (F-RGCs) and RGCs labeled in a transgenic mouse line W3. First, I presented studies of classifying subtypes of alpha RGCs. Cell attached recording followed by morphology reconstruction revealed four subtypes of alpha-like RGCs: Off-sustained, Off-transient, On-sustained, On-transient subtypes, each of which has distinct morphological properties. In addition, we found osteopontin (OPN) as a molecular marker for all alpha RGCs. Following this discovery, we studied the role of OPN in alpha RGCs, Analysis showed that alpha RGCs preferentially survive and regenerate compared with other RGCs, leading us to test whether OPN can promote axon regeneration. Indeed, by combining OPN with growth factors, we were able to promote axon regenerations of RGCs. Second, I presented work in classifying subtypes of F-RGCs, which are recognized by expressing a transcription factor, Foxp2. Combinatory expression of Foxp2 with other transcriptional factors divides F-RGCs into four subtypes, which form two pairs differing in their dendritic field sizes. Cell attached recording showed that one pair, F-minion and F-minioff RGCs, are direction-selective, while the other pair, F-midion and F-midioff RGCs, are not. Thus, we identified four new subtypes of RGCs labeled by transcriptional factor Foxp2. Third, I described initial efforts in classifying subtypes of RGCs labeled in the transgenic mouse line W3. W3 RGCs can be separated into two group based on their expression levels of fluorescent proteins, with the dimly labeled RGCs (W3D) remained uncharacterized. Initial analysis showed W3D RGCs include at least five subtypes of RGCs, which are different in their structures and physiological properties. Lastly, I described my work in developing a molecular tool for mapping electrical synaptic connections from genetically defined neurons or neuronal subtypes, making use of a dipeptide transporter, Pept2. Cells expressing Pept2 (in a Cre-dependent way) take up a gap junction permeable fluorescent dipeptide, which then diffuses and labels the coupled cells. We tested this method in cultured cells and validated it in mouse retina using AAV carrying Cre-dependent Pept2. I applied this method to one subtype of RGCs, J-RGCs, to label their coupling partners.
Biology, Molecular and Cellular

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18

Emanuel, Alan. "Signal Integration and Diversification by Melanopsin-Expressing Retinal Ganglion Cells". Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:33493393.

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There are three classes of light-sensing cells in the mammalian retina: rods, cones, and intrinsically photosensitive retinal ganglion cells (ipRGCs). This dissertation focuses on the signals generated by the ipRGCs, which are important for the regulation of many non-image-forming visual functions such as regulation of the circadian clock, pupillary light reflex, sleep, locomotor activity, and hormone levels. Dysregulation of these functions can have profound effects on health. How ipRGCs regulate these functions remains incompletely understood because many of their basic properties have not yet been established. To better understand ipRGCs, I conducted a quantitative electrophysiological examination of their light responses within the in vitro mouse retina. Chapter 2 presents evidence that melanopsin, the light-sensing pigment that initiates phototransduction within ipRGCs, has three stable states that are interconverted by light. Two of these states are silent and have distinct spectral sensitivities, which allows ipRGCs to integrate over a relatively broad range of wavelengths. The stability of the active state results in the production of a persistent response that long outlasts the offset of the stimulus and allows ipRGCs to integrate light over time. Most light stimuli, including short-wavelength and white light produce a large fraction of the active state and its associated persistent response. In contrast, long-wavelength light produces a much smaller fraction of the active state and can be used to decrease the persistent response. The effects of melanopsin tristability appear to be particularly suited for the functions regulated by ipRGCs. These effects are absent in other known photoreceptors, which have pigments with only one or two stable states. IpRGC phototransduction persists for minutes even after illumination has ceased because the signaling state of melanopsin is thermally stable. In Chapter 3, I describe experiments that examine how this persistence influences two fundamental aspects of ipRGC function: activation and adaptation. I found that increased persistence is associated with ipRGC activation that encodes a narrower band of light intensities. Thus, although persistence endows ipRGCs with temporal integration, it does so at the cost of dynamic range. In addition, persistence drives adaptation to desensitize the cell. Accordingly, acutely decreasing the persistent response with long-wavelength light can result in a subsequent recovery of sensitivity. However, this effect is highly variable across the population; some cells show greater desensitization from the long-wavelength light than resensitization from its reduction of the persistent response. Therefore, the balance of activation and adaptation differs among ipRGCs, such that light history may diversify the signals generated by the population. There are multiple subtypes of ipRGCs, but even a single subtype regulates many distinct functions. In Chapter 4, I describe a systematic approach for examination of the diversity in the biophysical parameters governing ipRGC signaling, including phototransduction, synaptic input, passive membrane properties, and spike generation. Comparison of these parameters across cells revealed a large degree of heterogeneity both between and within two morphologically-defined ipRGC subtypes. The diversity in ipRGC signal generation does not appear to divide among ipRGCs that project to different brain regions that control distinct functions; ipRGCs that project to the hypothalamus have diverse physiological properties that are highly overlapping with the ipRGCs that project to the pretectum. This suggests that functions driven by both areas have access to information from ipRGCs with a similar, broad range of characteristics. In summary, the research described within this dissertation has revealed that visual pigments can be tristable in physiological conditions and this tristability has unique consequences for signal generation. Furthermore, it has provided insight into the high degree of biophysical diversity that can be present even within a single, molecularly-defined type of neuron. These findings contribute to the emerging understanding of ipRGCs and their distinctions from the classical rod and cone photoreceptors.
Medical Sciences

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19

Chander, Divya. "Temporal contrast adaptation in identified types of retinal ganglion cells /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2002. http://wwwlib.umi.com/cr/ucsd/fullcit?p3071017.

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20

Lin, Xiaohui. "Modulation of retinal ganglion cell responses by the endocannabinoid system and the involvement of TRPV1 channels". Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/18946.

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The endocannabinoid (eCB) system was found to modulate synaptic transmission in the central nervous system (CNS). The retina carries out complex neural computations that involve several physiological mechanisms, including short and long-term plasticity phenomena. The mechanisms responsible for modifying the strength of retinal synaptic transmission, however, are not fully understood. Previous studies in the Vision Lab showed that bath application of a drug that elevates the concentration of endocannabinoids reduced the peak amplitude of visual-evoked postsynaptic potentials (vePSP) in retinal ganglion cells (RGCs) but paradoxically increased their spiking output. In addition, the rise in endocannabinoid concentration shifted the voltage dependence of the sodium current to the left. The reduction in vePSP amplitude is consistent with the known presynaptic effects of eCBs on synaptic transmission whilst it was postulated that the increase in spiking output could be mediated by TRPV1 receptors, which are nonselective ligand gated cation channel sensitive to eCBs and a broad range of other stimuli. This study investigated the potential role of TRPV1 channels in the modulation of RGCs excitability by recording their electrical activity in wild-type and TRPV1 knock-out mice using whole cell patch clamping techniques. We found that the endocannabinoid anandamide acts on TRPV1 channels to increase cell excitability. Increasing the levels of anandamide in the absence of TRPV1 channels, however, led to the activation of RGCs at more hyperpolarised potentials, suggesting that other targets of anandamide are involved in RGC modulation. Moreover, the TRPV1 agonist and antagonist capsaicin and capsazepine are likely to have non-specific effects as application of capsazepine was able to reduce cell excitability in the TRPV knockout mice (TRPV1-/-).

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21

Billock, Vincent Alan. "Hue and luminance multiplexing in type I r-g cells /". The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487330761219187.

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22

Dallimore, Elizabeth Jane. "Molecular and cellular characteristics of early vs late born retinal ganglion cells". University of Western Australia. School of Anatomy and Human Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0138.

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[Truncated abstract] Developmentally, the rodent retinocollicular projection is often thought of as a homogenous projection of retinal ganglion cell (RGC) axons, however the extensive period of RGC neurogenesis and sequential arrival of their axons into central targets such as the superior colliulus (SC) suggests otherwise. RGC axons are already present in the developing SC at embryonic (E) day 16.5-17. RGCs born on E15 have innervated the SC by birth, whereas axons derived from RGCs that are born last (E19) do not grow into the SC until postnatal (P) days 4-6 (Dallimore et al., 2002). These observations may go someway to explaining why, after SC lesions in rats at P2, there is greater growth distal to the lesion site compared to lesions made at P6 (Tan and Harvey, 1997b). It may be that the post lesion growth is simply de novo growth of axons from late-born RGCs rather than regeneration of pre-existing, injured axons. Early and late cohorts of growing RGC axons presumably encounter different developmental terrains as they grow from retina to central targets, possibly resulting in differences in developmental milestones and growth potentials. There may also be differences in guidance cues, further suggesting that gene expression in early vs late born RGCs may differ. To examine differences between early (E15) and late (E19) born RGCs during development, the time-course and extent of programmed RGC death in normal rat pups, and RGC death following the removal of target-derived trophic factors, was assessed. ... On the other hand, LCM captured GCL analysed for gene expression at P0 and P7 revealed decreases in AKT, Math5, Notch1, c-jun, DCC, Arginase-1 mRNA levels and a considerable decrease in GAP-43 expression. It is not surprising to see differences in gene expression between whole eye and the more specific GCL samples, as the cells in all layers of the retina have very different functions and different developmental profiles. It is important to note decreases in mRNA expression in the GCL for a number of the genes analysed at P0 and P7, reflecting cessation of RGC death and completion of axonal growth into central visual targets. I also examined at the protein level expression of DCC, Arginase1, c-Jun and Bcl-2 at birth (P0) in BrdU labeled RGCs born on E15 or E19. When comparing the percentage of double labelled cells compared to the total number of cells expressing each protein, Bcl-2, c-Jun and Arg1 were expressed more in E15 RGCs (22.90%, 72.71%, and 16.44% respectively in E15 RGCs, compared with 0.52%, 13.17% and 3.59% in E19 RGCs). In contrast, DCC was expressed more at birth in E19 RGCs (18.05% in E19 RGCs compared with 9.23% in E15 RGCs). This shows there is clearly a difference in the expression of proteins in the two cohorts of RGCs, which is consistent with PCR data and with their growth state as their axons encounter the changes in the newborn brain. The overall findings of this research suggest that seemingly homogenous populations of neurons are quite different in their developmental profile and in their response to injury. This work may provide new ways of determining better strategies for CNS repair and the most effective way of targeting cells for regeneration and survival.

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23

Cheung, Amanda Fung-ping. "Schwann cells promote axonal regeneration of retinal ganglion cells in young postnatal mice". Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400561.

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24

Rutkowski, Paul, e Christian Albrecht May. "Nutrition and Vascular Supply of Retinal Ganglion Cells during Human Development". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-215952.

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Abstract (sommario):

Purpose: To review the roles of the different vascular beds nourishing the inner retina [retinal ganglion cells (RGCs)] during normal development of the human eye, using our own tissue specimens to support our conclusions. Methods: An extensive search of the appropriate literature included PubMed, Google scholar, and numerous available textbooks. In addition, choroidal and retinal NADPH-diaphorase stained whole mount preparations were investigated. Results: The first critical interaction between vascular bed and RGC formation occurs in the sixth to eighth month of gestation leading to a massive reduction of RGCs mainly in the peripheral retina. The first 3 years of age are characterized by an intense growth of the eyeball to near adult size. In the adult eye, the influence of the choroid on inner retinal nutrition was determined by examining the peripheral retinal watershed zones in more detail. Conclusion: This delicately balanced situation of RGC nutrition is described in the different regions of the eye, and a new graphic presentation is introduced to combine morphological measurements and clinical visual field data.

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25

Ireland, Shelley Margaret Lorraine. "The plasticity of the visual system following damage of the brachium of the superior colliculus in neonatal and adult hamsters :". Thesis, [Hong Kong : University of Hong Kong], 1991. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13204907.

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26

Kalapesi, Freny B. Medical Sciences Faculty of Medicine UNSW. "Glaucoma, a study of neuroprotection using an in vitro model". Publisher:University of New South Wales. Medical Sciences, 2007. http://handle.unsw.edu.au/1959.4/40509.

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Glaucoma is a devastating blinding disease, caused by retinal ganglion cell (RGC) loss via apoptosis and clinically associated with raised intraocular pressure (IOP). Mainstream theories of glaucoma's pathogenesis detail loss of RGCs via indirect links to lOP; including mechanodistortion of optic nerve axons, trophic factor deficiency, ischaemia or excitotoxicity. A novel concept in the pathogenesis of glaucoma is that pressure alone could be a direct stimulus for RGC loss. Currently available glaucoma treatments are solely aimed at lowering lOP. Reduction ofIOP has been shown to reduce glaucomatous progression however RGC losses continue. Neuroprotection is an emerging field of research offering hope to neurodegenerative diseases, including glaucoma. This thesis investigated known glaucoma therapeutics with suggested neuroprotective activity in an in vitro glaucoma model using the RGC-5 cell line. To evaluate therapies, a suitable in vitro model was initially evaluated. The RGC-5 cell line was immunochemically demonstrated to possess NSE, a neuronal marker and Thy-1, an RGC marker. Glutamate excitotoxicity was investigated however excessive concentrations were required to cause significant in vitro RGC-5 cytotoxicity. Using a modified hydrostatic pressure model, reproducible pressure-induced RGC-5 apoptosis was demonstrated. Apoptosis was detected using cell morphology and confirmed with both early (caspase-3 and annexin V) and late (TUNEL) apoptotic markers. Despite the advantages of rapid, objective quantification, results indicated that flow cytometry of RGC-5 cells was not technically possible. I defined a modified laser scanning cytometry protocol, allowing for objective apoptosis quantification of TUNEL stained cells. Brimonidine is postulated to mediate receptor mediated RGC protection. Experiments conducted for this thesis, were the first to immunochemically demonstrate alpha2 adrenergic receptor expression on human RGCs and the RGC-5 cell line, suggesting direct cell mediated protection on the target neuron of glaucoma is possible and that the RGC-5 line is a useful in vitro target for experimentation. Both brimonidine and betaxolol were shown to confer protection to the RGC-5 cell line from pressure-induced apoptosis, under defined conditions. These results suggest that these drugs may confer direct cell-mediated protection, rather than indirect protection conferred via other retinal or glial cells, the anterior segment, the vasculature or some other means.

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27

任峰 e Feng Ren. "Immunoneurobiological studies of retinal ganglion neuronotrophic factor and its application in experimental treatment ofretinoblastoma". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B31233867.

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28

Ren, Feng. "Immunoneurobiological studies of retinal ganglion neuronotrophic factor and its application in experimental treatment of retinoblastoma /". Hong Kong : University of Hong Kong, 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13637605.

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29

Sodhi, Puneet. "Neuromodulation of Ganglion Cell Photoreceptors". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1428489662.

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30

游思維 e Siwei You. "Neuronal survival and axonal regeneration of retinal ganglion cells inadult hamsters". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B3123799X.

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31

Wu, Yi-Chieh Ph D. Massachusetts Institute of Technology. "Deciphering the neural code for retinal ganglion cells through statistical inference". Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/53320.

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Abstract (sommario):

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 85-87).
This work studies how the visual system encodes information in the firing patterns of retinal ganglion cells. We present a visual scene to a retina, obtain in-vitro recordings from a multi-electrode array, and attempt to identify or reconstruct the scene. Our approach uses the well-known linear-nonlinear Poisson model to characterize neural firing behavior and accounts for stochastic variability by fitting parameters using maximum likelihood. To characterize cells, we use white noise analysis followed by numerical optimization to maximize the likelihood of the experimentally observed neural responses. We then validate our method by keeping these fitted parameters constant and using them to estimate the speed and direction of moving edges, and to identify a natural scene out of a set of possible candidates. Limitations of our approach, including reconstruction fidelity and the validity of various assumption are also examined through simulated cell responses.
by Yi-Chieh Wu.
S.M.

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32

Chen, Baiyu, e 陳白羽. "Suprachiasmatic nucleus projecting retinal ganglion cells in golden hamsters development, morphology and relationship with NOS expressingamacrine cells". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37238218.

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33

Chen, Baiyu. "Suprachiasmatic nucleus projecting retinal ganglion cells in golden hamsters development, morphology and relationship with NOS expressing amacrine cells". Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37238218.

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34

Yang, Ming-Hui. "A water channel (AQP9) in retinal ganglion cell apoptosis and glaucoma". Fort Worth, Tex. : Texas Christian University, 2007. http://etd.tcu.edu/etdfiles/available/etd-04202007-153701/unrestricted/yang.pdf.

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35

Jalligampala, Archana [Verfasser]. "Zapping the Retina - Understanding electrical responsiveness and electrical desensitization in mouse retinal ganglion cells / Archana Jalligampala". Tübingen : Universitätsbibliothek Tübingen, 2020. http://d-nb.info/121463978X/34.

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36

Chiu, Kin. "Immune modulation on retinal ganglion cell survival in experimental glaucoma". Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B40987693.

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37

Renna, Jordan Michael. "The role of strychnine-sensitive nACHRS in rabbit retinal OFF ganglion cells". Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2008. https://www.mhsl.uab.edu/dt/2008p/renna.pdf.

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38

Li, Shengxiu. "The role of glial cells in the survival and axonal regeneration of retinal ganglion cells /". Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20897650.

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39

You, Siwei. "Neuronal survival and axonal regeneration of retinal ganglion cells in adult hamsters /". Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19859946.

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40

Robinson, Martha Rose. "Spatial and temporal dynamics of retinal ganglion cells with different photoreceptor inputs". Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1572515/.

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Abstract (sommario):

The retina must operate over a wide range of light levels. Two classes of input cells, rods and cones, specialised to different light conditions evolved to achieve this task. This thesis examines how interactions between these two classes shape retinal output as the light level changes, and the extent to which loss of one class can alter processing of the remaining class. Retinal ganglion cell (RGC) receptive elds were characterised using multielectrode array recordings performed during presentation of spatiotemporal white noise across a 4.5 log10 light level range. Receptive fi eld properties were compared between wild-type mice, mice lacking functional cones (cpfl1 model of achromatopsia), and mice lacking functional rods (rd17 model of congenital stationary night blindness). The response of RGCs to otherwise identical stimuli changed with ambient light level. In low light conditions, wild-type RGCs had a longer latency to spike and were shifted towards higher temporal and lower spatial frequency tuning. Of those RGCs characterised at multiple light levels, 28% changed the polarity of their receptive fields between ON and OFF. These polarity switches occurred between every possible pair of light levels, and several cells were observed to switch multiple times. RGCs which switched polarity were identi ed in both rd17 and cpfl1 mice, indicating that at least some circuit mechanisms responsible are driven by a single photoreceptor cell class. Loss of function in one photoreceptor cell class altered visual processing of inputs from the remaining class. In low light conditions, RGCs in cpfl1 mice showed shorter latency to spike and a marked shift towards higher temporal frequency tuning, a receptive field property that is often understood as indicating tuning to visual motion. This difference in visual processing could result in behavioural differences, for instance these mice may exhibit better contrast sensitivity at temporal frequencies in low light conditions.

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41

Rakowicz, Wojciech Piotr. "The regulation of death in retinal ganglion cells and spinal motor neurons". Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621305.

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42

Gauthier, Jeffrey Lee. "The population perspective how primate retinal ganglion cells collectively encode visual space /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p3311417.

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Abstract (sommario):

Thesis (Ph. D.)--University of California, San Diego, 2008.
Title from first page of PDF file (viewed July 31, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 48-53).

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43

Ran, Yanli [Verfasser], e Thomas [Akademischer Betreuer] Euler. "Dendritic integration in mouse retinal ganglion cells / Yanli Ran ; Betreuer: Thomas Euler". Tübingen : Universitätsbibliothek Tübingen, 2020. http://d-nb.info/1205313435/34.

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44

La, Morgia Chiara <1977&gt. "Melanopsin Retinal Ganglion Cells: relevance to circadian rhythms and sleep in neurodegeneration". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4796/1/La_Morgia_Chiara_tesi.pdf.

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Abstract (sommario):

In this PhD thesis 3 projects were addressed focusing on the melanopsin retinal ganglion cells (mRGCs) system and its relevance for circadian rhythms and sleep in neurodegeneration. The first project was aimed at completing the characterization of mRGCs system in hereditary optic neuropathies (LHON and DOA). We confirmed that mRGCs are relatively spared also in post-mortem retinal specimens of a DOA case and pupillometric evaluation of LHON patients showed preservation of the pupillary light reflex, with attenuated responses compared to controls. Cell studies failed to indicate a protective role exerted by melanopsin itself. The second project was aimed at characterizing the possible occurrence of optic neuropathy and rest-activity circadian rhythm dysfunction in Alzheimer (AD) and Parkinson disease (PD), as well as, at histological level, the possible involvement of mRGCs in AD. OCT studies demonstrated a subclinical optic neuropathy in both AD and PD patients, with a different pattern involving the superior and nasal quadrants in AD and the temporal quadrant in PD. Actigraphic studies demonstrated a tendency towards an increased intradaily variability (IV) and reduced relative amplitude (RA) of rest-activity circadian rhythm in AD and a significant increased IV a reduced RA in PD. Immunohistochemical analysis of post-mortem retinal specimens and optic nerve cross-sections of neuropathologically confirmed AD cases demonstrated a significant loss of mRGCs and a nearly significant loss of axons in AD compared to controls. The mRGCs were affected in AD independently from age and magnitude of axonal loss. Overall these results suggest a role of the mRGCs system in the pathogenesis of circadian dysfunction in AD. The third project was aimed at evaluating the possible association between a single nucleotide polymorphism of the OPN4 gene and chronotype or SAD, failing to find any significant association with chronotype, but showing a non-significant increment of TT genotype in SAD.

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45

La, Morgia Chiara <1977&gt. "Melanopsin Retinal Ganglion Cells: relevance to circadian rhythms and sleep in neurodegeneration". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4796/.

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Abstract (sommario):

In this PhD thesis 3 projects were addressed focusing on the melanopsin retinal ganglion cells (mRGCs) system and its relevance for circadian rhythms and sleep in neurodegeneration. The first project was aimed at completing the characterization of mRGCs system in hereditary optic neuropathies (LHON and DOA). We confirmed that mRGCs are relatively spared also in post-mortem retinal specimens of a DOA case and pupillometric evaluation of LHON patients showed preservation of the pupillary light reflex, with attenuated responses compared to controls. Cell studies failed to indicate a protective role exerted by melanopsin itself. The second project was aimed at characterizing the possible occurrence of optic neuropathy and rest-activity circadian rhythm dysfunction in Alzheimer (AD) and Parkinson disease (PD), as well as, at histological level, the possible involvement of mRGCs in AD. OCT studies demonstrated a subclinical optic neuropathy in both AD and PD patients, with a different pattern involving the superior and nasal quadrants in AD and the temporal quadrant in PD. Actigraphic studies demonstrated a tendency towards an increased intradaily variability (IV) and reduced relative amplitude (RA) of rest-activity circadian rhythm in AD and a significant increased IV a reduced RA in PD. Immunohistochemical analysis of post-mortem retinal specimens and optic nerve cross-sections of neuropathologically confirmed AD cases demonstrated a significant loss of mRGCs and a nearly significant loss of axons in AD compared to controls. The mRGCs were affected in AD independently from age and magnitude of axonal loss. Overall these results suggest a role of the mRGCs system in the pathogenesis of circadian dysfunction in AD. The third project was aimed at evaluating the possible association between a single nucleotide polymorphism of the OPN4 gene and chronotype or SAD, failing to find any significant association with chronotype, but showing a non-significant increment of TT genotype in SAD.

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46

Rheey, Jinguen. "Otx2 promotes survival of injured adult retinal ganglion cells non cell-autonomously and regulates development of inner retinal cells in post-natal mouse cell autonomously". Paris 6, 2011. http://www.theses.fr/2011PA066176.

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47

Fu, Qingling. "Characterization of novel neuroprotectants for rescuing retinal ganglion cell loss in an ocular hypertensive model of glaucoma". Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B39557510.

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48

趙麗萍 e Li-ping Zhao. "In vitro studies of a neuronotrophic factor from rat superior colliculus specific for retinal ganglion cells". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1991. http://hub.hku.hk/bib/B31232905.

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49

Fu, Qingling, e 付清玲. "Characterization of novel neuroprotectants for rescuing retinal ganglion cell loss in an ocular hypertensive model of glaucoma". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39557510.

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50

Chiu, Kin, e 趙健. "Immune modulation on retinal ganglion cell survival in experimental glaucoma". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40987693.

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Tesi sul tema "Retinal ganglion cells"

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