181 research outputs found
Translational neuroprotection research in glaucoma: a review of definitions and principles
No full textThe maintenance of vision, through prevention and attenuation of neuronal injury in glaucoma, forms the basis of current clinical practice. Currently, the reduction of intraocular pressure is the only proven method to achieve these goals. Although this strategy enjoys considerable success, some patients progress to blindness; hence, additional management options are highly desirable. Several terms describing treatment modalities of neuronal diseases with potential applicability to glaucoma are used in the literature, including neuroprotection, neurorecovery, neurorescue and neuroregeneration. These phenomena have not been defined within a coherent framework. Here, we suggest a set of definitions, postulates and principles to form a foundation for the successful translation of novel glaucoma therapies from the laboratory to the clinic.Robert J Casson, Glyn Chidlow, Andreas Ebneter, John PM Wood, Jonathan Crowston and Ivan Goldber
Chapter 16: Ultrasound biomicroscopy
No full textUltrasound biomicroscopy (UBM) is a diagnostic imaging technique which was developed to improve the visualization of the anterior segment structures. The high resolution of UBM images significantly contributed to the qualitative comprehension of the pathogenic mechanism involved in various ocular diseases, especially in glaucoma management. UBM has been used to elucidate the etiology of plateau iris syndrome, to demonstrate the hypothesis on the angle closure in two times, to confirm the theory of the reverse pupillary block in the pigment dispersion syndrome and ciliary-block as the main mechanism involved in the pathogenesis of malignant glaucoma. Furthermore, UBM is a useful tool for examination of filtering surgical techniques and causes of failure. © 2015, Elsevier Limited. All rights reserved
Fabricating Women: The Seamstresses of Old Regime France, 1675 1791. By Clare Haru Crowston. Durham, NC: Duke University Press, 2001. Pp. xviii, 508. 21.95, paper.
No full textThis book is a masterpiece. The author has marshaled a massive amount of information, and in the tradition of the best history writing she uses this to cast new light on our knowledge of eighteenth-century seamstresses and the society in which they lived. The meticulous detail is such that Clare Haru Crowston s work on this topic is unlikely to be superseded. Moreover, the book is beautifully produced. The illustrations educate. The dustcover alone is a delight.
Definition of glaucoma: clinical and experimental concepts
No full textGlaucoma is a term describing a group of ocular disorders with multi-factorial etiology united by a clinically characteristic intraocular pressure-associated optic neuropathy. It is not a single entity and is sometimes referred to in the plural as the glaucomas. All forms are potentially progressive and can lead to blindness. The diverse conditions that comprise glaucoma are united by a clinically characteristic optic neuropathy: glaucomatous optic neuropathy (GON). Evidence suggests that the primary site of neurological injury is at the optic nerve head. This fact enables the conditions to be grouped, irrespective of the causal mechanism(s). The term experimental glaucoma implies model resemblance to the human condition. We propose that 'experimental glaucoma' be restricted to animal models with demonstrable features of GON and/or evidence of a primary axonopathy at the optic nerve head. A fundamental inadequacy in this framework is any reference to the pathogenesis of GON, which remains unclear.Robert J Casson, Glyn Chidlow, John PM Wood, Jonathan G Crowston, and Ivan Goldber
Retinal energy metabolism in health and glaucoma
No full textAvailable online 23 July 2020Energy metabolism refers to the processes by which life transfers energy to do cellular work. The retina's relatively large energy demands make it vulnerable to energy insufficiency. In addition, evolutionary pressures to optimize human vision have been traded against retinal ganglion cell bioenergetic fragility. Details of the metabolic profiles of the different retinal cells remain poorly understood and are challenging to resolve. Detailed immunohistochemical mapping of the energy pathway enzymes and substrate transporters has provided some insights and highlighted interspecies differences. The different spatial metabolic patterns between the vascular and avascular retinas can account for some inconsistent data in the literature. There is a consilience of evidence that at least some individuals with glaucoma have impaired RGC energy metabolism, either due to impaired nutrient supply or intrinsic metabolic perturbations. Bioenergetic-based therapy for glaucoma has a compelling pathophysiological foundation and is supported by recent successes in animal models. Recent demonstrations of visual and electrophysiological neurorecovery in humans with glaucoma is highly encouraging and motivates longer duration trials investigating bioenergetic neuroprotection.Robert J. Casson, Glyn Chidlow, Jonathan G. Crowston, Pete A. Williams, John P. M. Woo
A comparison of differentiation protocols for RGC-5 cells
No full textPurpose: Although the RGC-5 cell line is widely used in retinal ganglion cell (RGC) research, recent data have raised questions about the nature of these cells. The authors performed a systematic analysis of RGC-5 cells to determine which RGC or neuronal markers are expressed after treatment with known differentiating agents, thus providing further insight into the nature of these cells and assisting in defining their future use. Methods: RGC-5 cells were treated for 5 days with staurosporine (STSN; 316 nM), trichostatin A (TSA; 500 nM), or succinylconcanavalin A (sConA; 50 _g/mL), after which they were assayed for specific marker antigen/mRNA expression. Treated cells were also assayed for excitotoxic responsiveness. Results: Neither treated nor untreated RGC-5 cells expressed any specific RGC marker mRNAs or proteins (Brn-3, neurofilaments, Thy-1) or calbindin, calretinin, synaptophysin, PKC_, or glial fibrillary acidic protein. However, control RGC-5 cells did express the neuronal markers tau, _III-tubulin, microtubule-associated protein (MAP)-1b, MAP2, and PGP9.5. Although treatment with sConA had no effect on the expression of these markers, STSN and (dose dependently) TSA increased their expression and induced excitotoxic responsiveness. All cells, treated or not, expressed high levels of nestin but no other progenitor cell markers. All cells also expressed cone-specific, but not rod-specific, opsin indicative of cone photoreceptor lineage. Conclusions: RGC-5 cells expressed neuronal, but not RGCspecific, markers that were dose dependently upregulated by TSA. Hence, TSA provided the best tested means to terminally differentiate the cells to a neuronal phenotype from a precursor- like lineage.John P. M. Wood, Glyn Chidlow, Tuyet Tran, Jonathan G. Crowston, and Robert J. Casso
Relief for retinal neurons under pressure
No full textA dietary supplement may offer protection from loss of vision in glaucoma</jats:p
Neuroprotection in glaucoma
No full textGlaucoma is a neurodegenerative disease characterized by loss of retinal ganglion cells and their axons. Recent evidence suggests that intraocular pressure (IOP) is only one of the many risk factors for this disease. Current treatment options for this disease have been limited to the reduction of IOP; however, it is clear now that the disease progression continues in many patients despite effective lowering of IOP. In the search for newer modalities in treating this disease, much data have emerged from experimental research the world over, suggesting various pathological processes involved in this disease and newer possible strategies to treat it. This review article looks into the current understanding of the pathophysiology of glaucoma, the importance of neuroprotection, the various possible pharmacological approaches for neuroprotection and evidence of current available medications
- …
