859 resultados para Eye
Resumo:
The European Eye Epidemiology (E3) consortium is a recently formed consortium of 29 groups from 12 European countries. It already comprises 21 population-based studies and 20 other studies (case-control, cases only, randomized trials), providing ophthalmological data on approximately 170,000 European participants. The aim of the consortium is to promote and sustain collaboration and sharing of data and knowledge in the field of ophthalmic epidemiology in Europe, with particular focus on the harmonization of methods for future research, estimation and projection of frequency and impact of visual outcomes in European populations (including temporal trends and European subregions), identification of risk factors and pathways for eye diseases (lifestyle, vascular and metabolic factors, genetics, epigenetics and biomarkers) and development and validation of prediction models for eye diseases. Coordinating these existing data will allow a detailed study of the risk factors and consequences of eye diseases and visual impairment, including study of international geographical variation which is not possible in individual studies. It is expected that collaborative work on these existing data will provide additional knowledge, despite the fact that the risk factors and the methods for collecting them differ somewhat among the participating studies. Most studies also include biobanks of various biological samples, which will enable identification of biomarkers to detect and predict occurrence and progression of eye diseases. This article outlines the rationale of the consortium, its design and presents a summary of the methodology.
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Complex molecular events underlie vertebrate eye development and disease. The eye is composed of two major tissue types: the anterior and posterior segments. During development, the retinal progenitor cells differentiate into six neuronal and one non-neuronal cell types. These cell types later organize into the distinct laminar structure of the mature retina which occupies the posterior segment. In the developed anterior segment, both the ciliary body and trabecular meshwork regulate intraocular pressure created by the aqueous humor. The disruption in intraocular pressure can lead to a blinding condition called glaucoma. To characterize molecular mechanisms governing retinal development and glaucoma, two separate mouse knockout lines carrying mutations in math5 and myocilin were subjected to a series of in vivo analyses. ^ Math5 is a murine homologue of Drosophila atonal , a bHLH proneural gene essential for the formation of photoreceptor cells. The expression of math5 coincides with the onset of retinal ganglion cell differentiation. The targeted deletion of mouse math5 revealed that a null mutation inhibits the formation of a majority of the retinal ganglion cells. The mutation also interferes with the normal development of other retinal cell types such as amacrine, bipolar and photoreceptor cells. These results suggest that math5 is a proneural gene responsible for differentiation of retinal ganglion cells and may also have a role in normal development of other neuronal cell types within the retina. ^ Myocilin has two unique protein coding regions bearing homology to non-muscle myosin of Dictyostelium discoideum and to olfactomedin, an extracellular matrix molecule first described in the olfactory epithelium of the bullfrog. Recently, autosomal dominant forms of myocilin mutations have been found in individuals with primary open-angle glaucoma. The genetic linkage to glaucoma suggests a role of myocilin in normal intraocular pressure and ocular function. However, the analysis of mice heterozygous and homozygous for a targeted null mutation in myocilin indicates that it is dispensable for normal intraocular pressure or ocular function. Additionally, the lack of a discernable phenotype in both heterozygous and null mice suggests that haploinsufficiency is not a critical mechanism for MYOC-associated glaucoma in humans. Instead, disease-causing mutations likely act by gain of function. ^ In summary, these studies provide novel insights into the embryonic development of the vertebrate retina, and also begin to uncover the molecular mechanisms responsible for the pathogenesis of glaucoma. ^
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By looking at Great Britain and the American colonies in conjunction with the larger British Atlantic Empire, historians can better understand the political, social, and cultural transformations that occurred when transatlantic actors met. William Samuel Johnson is an example of an "ordinary" agent who nonetheless had extensive contacts with numerous British and American thinkers. While acting on Connecticut's behalf in London between 1767 and 1771, he sent reports back to Connecticut governors Jonathan Trumbull and William Pitkin on parliamentary proceedings while corresponding with the people who traveled around the Atlantic world during this critical period-merchants, seafarers, emigrants, soldiers, missionaries, radicals and conservatives, reformers, and politicians. He is also representative of the late eighteenth-century empire writ large. Agents, who had once been a source of stability in the far-flung colonies, became a destabilizing force as confusion and conflict grew over conceptual ideas of what constituted "the empire" and who was included in it. Johnson was a sane observer in the midst of the ideological and administrative upheaval of the 1760's and 1770's. His subsequent loyalism and political obscurity during the war years was in many ways a result of his attempts to reconcile various factional interests during his tenure as an agent. Although he did his best to resolve these divisions and provide an accurate account of the powerful nationalistic forces gathering on both sides of the Atlantic on the eve of the American Revolution, the agents' collective failures as transatlantic mediators helped bring about the collapse of an imperial community. This disintegration had dramatic effects on the whole of the Atlantic world.
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Purpose. Fluorophotometry is a well validated method for assessing corneal permeability in human subjects. However, with the growing importance of basic science animal research in ophthalmology, fluorophotometry’s use in animals must be further evaluated. The purpose of this study was to evaluate corneal epithelial permeability following desiccating stress using the modified Fluorotron Master™. ^ Methods. Corneal permeability was evaluated prior to and after subjecting 6-8 week old C57BL/6 mice to experimental dry eye (EDE) for 2 and 5 days (n=9/time point). Untreated mice served as controls. Ten microliters of 0.001% sodium fluorescein (NaF) were instilled topically into each mouse’s left eye to create an eye bath, and left to permeate for 3 minutes. The eye bath was followed by a generous wash with Buffered Saline Solution (BSS) and alignment with the Fluorotron Master™. Seven corneal scans using the Fluorotron Master were performed during 15 minutes (1 st post-wash scans), followed by a second wash using BSS and another set of five corneal scans (2nd post-wash scans) during the next 15 minutes. Corneal permeability was calculated using data calculated with the FM™ Mouse software. ^ Results. When comparing the difference between the Post wash #1 scans within the group and the Post wash #2 scans within the group using a repeated measurement design, there was a statistical difference in the corneal fluorescein permeability of the Post-wash #1 scans after 5 days (1160.21±108.26 vs. 1000.47±75.56 ng/mL, P<0.016 for UT-5 day comparison 8 [0.008]), but not after only 2 days of EDE compared to Untreated mice (1115.64±118.94 vs. 1000.47±75.56 ng/mL, P>0.016 for UT-2 day comparison [0.050]). There was no statistical difference between the 2 day and 5 day Post wash #1 scans (P=.299). The Post-wash #2 scans demonstrated that EDE caused a significant NaF retention at both 2 and 5 days of EDE compared to baseline, untreated controls (1017.92±116.25, 1015.40±120.68 vs. 528.22±127.85 ng/mL, P<0.05 [0.0001 for both]). There was no statistical difference between the 2 day and 5 day Post wash #2 scans (P=.503). The comparison between the Untreated post wash #1 with untreated post wash #2 scans using a Paired T-test showed a significant difference between the two sets of scans (P=0.000). There is also a significant difference between the 2 day comparison and the 5 day comparison (P values = 0.010 and 0.002, respectively). ^ Conclusion. Desiccating stress increases permeability of the corneal epithelium to NaF, and increases NaF retention in the corneal stroma. The Fluorotron Master is a useful and sensitive tool to evaluate corneal permeability in murine dry eye, and will be a useful tool to evaluate the effectiveness of dry eye treatments in animal-model drug trials.^
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Schizophrenia is the most prevalent mental disorder in the world, affecting approximately one percent of the population. Antipsychotic medications have successfully treated schizophrenic psychotic symptoms for years, however their positive effects on cognitive dysfunction, a core feature of schizophrenia, are inconclusive. Recent studies have shown that improved cognitive functioning is most often associated with the best long-term prognosis. Thus, clarifying the cognitive effects of commonly prescribed antipsychotic medications is pivotal to improving quality of life and long-term care of schizophrenic patients.^ Previous studies on cognitive dysfunction in schizophrenia utilized complex neuropsychological tasks requiring many intact areas of the brain for proper completion. These complexities make interpretation of acquired data difficult. Recently, eye movements have been identified as a more effective surrogate for investigating cognitive functioning. Eye movements are easily measured, require known discrete areas of the brain for processing, and are ubiquitous. They influence what we attend to and process in the brain; thus they are a pivotal aspect of cognitive functioning. This study sought to examine the effects of antipsychotic medications on eye movements in forty-two schizophrenic patients. These patients were divided equally into the three tested medication groups: haloperidol, olanzapine, and aripiprazole. To the extent possible, these groups were further separated into task-impaired and task-nonimpaired subgroups, and again analyzed. Clinical and neuropsychological scales were administered to assess clinical and eye movement changes.^ The results of this study found the olanzapine-treated group exhibited superior cognitive effects to the aripiprazole-treated group, who was superior to the haloperidol-treated group. Furthermore, upon subdivision into cognitively impaired and nonimpaired subgroups, both olanzapine-treated subgroups continued to show improvement, while only the aripiprazole-treated impaired subgroup showed cognitive benefit. The haloperidol-treated nonimpaired subgroup actually demonstrated worsening effects. Interestingly, despite the cognitive decline of some subgroups, the clinical assessment results indicated virtually all subgroups exhibited significant clinical improvement. Hence, careful selection of an antipsychotic medication is crucial, as this study shows some treatments may help whereas others may hinder cognitive functioning in schizophrenia. ^ The results of this study are extremely important given the relationship between cognitive improvement and long-term prognosis in schizophrenia. Finally, and perhaps most importantly, these results indicate that clinical improvement is not necessarily indicative of cognitive improvement. ^
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Purpose. The measurement of quality of life has become an important topic in healthcare and in the allocation of limited healthcare resources. Improving the quality of life (QOL) in cancer patients is paramount. Cataract removal and lens implantation appears to improve patient well-being of cancer patients, though a formal measurement has never been published in the US literature. In this current study, National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25), a validated vision quality of life metric, was used to study the change in vision-related quality of life in cancer patients who underwent cataract extraction with intraocular lens implantation. ^ Methods. Under an IRB approved protocol, cancer patients who underwent cataract surgery with intraocular lens implantation (by a single surgeon) from December 2008 to March 2011, and who had completed a pre- and postoperative NEI-VFQ-25 were retrospectively reviewed. Post-operative data was collected at their routine 4-6 week post-op visit. Patients' demographics, cancer history, their pre and postoperative ocular examinations, visual acuities, and NEI-VFQ-25 with twelve components were included in the evaluation. The responses were evaluated using the Student t test, Spearman correlation and Wilcoxon signed rank test. ^ Results. 63 cases of cataract surgery (from 54 patients) from the MD Anderson Cancer Center were included in the study. Cancer patients had a significant improvement in the visual acuity (P<0.0001) postoperatively, along with a significant increase in vision-related quality of life (P<0.0001). Patients also had a statistically significant improvement in ten of the twelve subcategories which are addressed in the NEI-VFQ-25. ^ Conclusions. In our study, cataract extraction and intraocular implantation showed a significant impact on the vision-related quality of life in cancer patients. Although this study includes a small sample size, it serves as a positive pilot study to evaluate and quantify the impact of a surgical intervention on QOL in cancer patients and may help to design a larger study to measure vision related QOL per dollar spent for health care cost in cancer patients.^
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Paciente de 60 años de edad y sexo femenino con esclerodermia y miopía alta bilateral que consulta por estrabismo y ptosis palpebral. El estrabismo consiste en esotropía progresiva con hipotropía de ojo derecho (OD) asociado a miopía alta axial con gran tamaño del globo ocular medido por ecometría ultrasónica que conjuntamente con imágenes de Resonancia Magnética Nuclear (RMN) llevan al diagnóstico de Síndrome MAPE (Miopic Acquired Progressive Esotropia). La hipotropía se diagnostica como heavy eye (ojo pesado). El tratamiento del estrabismo mediante cirugía de retroceso de recto medio derecho con técnica de suturas ajustables corrigió la esotropía mientras que la normalización del trayecto del recto lateral descendido no mejoró la hipotropía en esta paciente. Ésta se compensó parcialmente con el plegamiento ajustable del recto superior. Persiste la ptosis palpebral causada por la esclerodermia.
Resumo:
La integración de las nuevas tecnologías en el proceso de rehabilitación permite la generación de terapias personalizadas, ubicuas y basadas en la evidencia. Tecnologías como el vídeo interactivo son propicias para el desarrollo de entornos virtuales en los que el paciente se ve inmerso dentro de actividades de la vida diaria en los que tiene que lograr un objetivo ecológico en un contexto seguro, controlado y adaptado a su perfil disfuncional. Dentro de este marco de rehabilitación la interacción visual paciente-entorno virtual se entiende como el mecanismo de comunicación principal, siendo además la atención visual un reflejo del estado cognitivo del paciente. El trabajo presentado en este artículo permite la integración de un sistema de eye-tracking con un entorno de neurorrehabilitación basado en vídeo interactivo. El objetivo último del sistema es la monitorización en tiempo real de la atención visual del usuario durante el proceso de neurorrehabilitación. Esta monitorización permite no sólo reproducir la ejecución de la actividad junto con el foco de la mirada, sino también detectar faltas de atención por parte del usuario, que permiten al vídeo interactivo reaccionar y adaptar la presentación de estímulos para ayudar a centrar su atención y así completar el objetivo de la actividad.
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The use of Biophotonic Sensing Cells (BICELLs) based on micro-nano pattemed photonic architectures has been recently proven as an efficient methodology for label-free biosensing by using Optical Interrogation [1]. According to this, we have studied the different optical response for a specific typology of BICELL, consisting of structures of SU -8. This material is biocompatible with different types of biomolecules and can be immobilized on its sensing surface. In particular, we have measured the optical response for a biomarker in clinic diagnostic of dry eye. Although different proteins can be enstudied such as: PRDX5, ANXA 1, ANXA 11, CST 4, PLAA Y S 1 OOA6 related with ocular surface (dry eye), for this work PLAA (phospholipase A2) is studied by means of label free biosensing based on BICELLs for analyzing the performance and specificity according with means values of concentration in ROC curves.