To test the hypothesis that the same mechanisms mediate form deprivation and lens-induced myopia, the ocular growth responses of chicks alternately exposed to lenses and diffusers at regular intervals (3h) were compared to those of chicks exposed to either negative lenses or diffusers alone. In total, there were four experiments: (1) -15 D lenses and/or diffusers on normal birds, (2) -15 D lens...

The lens is derived from surface ectodermal cells which lie directly over the optic vesicle from which they are separated by the basement membranes and a thin interepithelial space. Early differentiation, folloicing induction, involves forming a compact disk of these epithelial cells in luhich the intercellular spaces have disappeared and their height increased. This disk or placode invaginates...

AIM To determine a suitable intraocular lens for implantation in patients at high risk of lens exposure to silicone oil in their lifetime. METHODS PMMA, AcrySof, AR40, AQUA-Sense, and Raysoft lenses were examined. Each lens was immersed for 5 minute intervals in balanced salt solution (BSS), in stained silicone oil, and again in BSS before being photographed in air and in BSS. Percentage sili...

Results. During ocular development, aB-crystallin transcripts are present in the lens placode at E9.5. Transcripts of aA-crystallin are first observed in the lens cup at E10 to 10.5. During subsequent development of the lens, aA crystallin transcripts are most abundant in the fiber cells, and aB crystallin mRNA is preferentially expressed in epithelial cells. Transcripts of aAcrystallin were de...

purpose: to describe a case with a rare complication of posterior chamber intraocular lens (pc-iol) implantation in a patient who had undergone extracapsular cataract extraction (ecce) two years before case report: a 80-year-old diabetic woman presented with an exposed pc-iol in her left eye with a history of mechanical trauma. slit-lamp examination revealed an extruded pc-iol lied on the anter...

objective(s) extracellular matrix (ecm) and basement membrane (bm) play important roles in many developmental processes during development and after birth. among the components of the bm, collagen fibers specially type iv are the most important parts. the aim of this study was to determine the time when collagen type iv appears in the bm of lens structure during mouse embryonic development. mat...

background: palliative whole brain radiotherapy (wbrt) has been the standard treatment for brain metastases. ionizing radiation is known to be one of the most potent cataractogenic agents. we aimed to evaluate two different radiotherapy techniques with respect to the doses received by the organs at risk (oar) in patients with brain metastasis who undergone wbrt. materials and methods: ten conse...

Activation of the first lens-specific gene of the chicken, delta 1-crystallin, is dependent on a group of lens nuclear factors, deltaEF2, interacting with the delta1-crystallin minimal enhancer, DC5. One of the deltaEF2 factors was previously identified as SOX2. We show that two related SOX proteins, SOX1 and SOX3, account for the remaining members of deltaEF2. Activation of the DC5 enhancer is...

Trauma or disease in the CNS often leads to neuronal death and consequent loss of functional connections. The idea has been put forward that strategies aimed at repairing the injured CNS involve stimulation of both neuronal survival and axon regeneration. We tested this hypothesis in the adult rat retinocollicular system by combining two strategies: (i) exogenous administration of brain-derived...

The development of modeling algorithms for adaptive optics systems is important for evaluating both performance and design parameters prior to system construction. Two of the most critical subsystems to be modeled are the binary optic design and the adaptive control system. Since these two are intimately related, it is beneficial to model them simultaneously. Optic modeling techniques have some...