salamander retinal ganglion: Topics by WorldWideScience.org

Melanopsin-expressing retinal ganglion-cell photoreceptors: cellular diversity and role in pattern vision

New visual pigments were formed with 4-hydroxy retinals in isolated vertebrate rod photoreceptors by exposing bleached rods from the tiger salamander, Ambystoma tigrinum, to lipid vesicles containing...Full Text Available

1990-01-01

Topically administered timolol and dorzolamide reduce intraocular pressure and protect retinal ganglion cells in a rat experimental glaucoma model

Using the photopigment melanopsin, intrinsically photosensitive retinal ganglion cells (ipRGCs) respond directly to light to drive circadian clock resetting and pupillary constriction. We now...Full Text Available

2010-07-15

Functional and morphological effects of laser-induced ocular hypertension in retinas of adult albino Swiss mice

Aims: This study sought to elucidate the effects of timolol and dorzolamide on intraocular pressure (IOP) and retinal ganglion cell (RGC) death in an experimental...Full Text Available

2005-04-01

Development of melanopsin-based irradiance detecting circuitry

PurposeTo investigate the effects of laser photocoagulation (LP)-induced ocular hypertension (OHT) on the survival and retrograde axonal transport of retinal ganglion cells (RGC),...Full Text Available

Channelrhodopsin-2 gene transduced into retinal ganglion cells restores functional vision in genetically blind rats

BackgroundMost retinal ganglion cells (RGCs) convey contrast and motion information to visual brain centers. Approximately 2% of RGCs are intrinsically photosensitive (ipRGCs), express...Full Text Available

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To test the hypothesis that transduction of the channelrhodopsin-2 (ChR2) gene, a microbial-type rhodopsin gene, into retinal ganglion cells of genetically blind rats will restore functional vision, we recorded visually evoked potentials and tested the experimental rats for the presence of optomotor responses. The N-terminal fragment of the ChR2 gene was fused to the fluorescent protein Venus and inserted into an adeno-associated virus to make AAV2-ChR2V. AAV2-ChR2V was injected intravitreally into the eyes of 6-month-old dystrophic RCS (rdy/rdy) rats. Visual function was evaluated six weeks after the injection by recording visually evoked potentials (VEPs) and testing optomotor responses. The expression of ChR2V in the retina was investigated histologically. We found that VEPs could not b...

2010-01-01

C57BL/6J, DBA/2J, and DBA/2J.Gpnmb⁺ mice have different visual signal processing in the inner retina

Detection of Visual Deficits in Aging DBA/2J Mice by Two Behavioral Assays

PurposeTo characterize differences in retinal ganglion cell (RGC) function in mouse strains relevant to disease models. C57BL/6J (B6) and DBA/2J (D2) are the two most common mouse...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

Purpose: The DBA/2J mice have been used as an animal model for human pigmentary glaucoma. However, these mice develop various degrees of disease symptoms at different ages, making it difficult to detect pathological changes of retinal degeneration at glaucoma onset. The purpose of this study is to develop a non-invasive assay to identify individual mice that develop visual deficits. Materials and Methods: We apply two behavioral tests, a swimming test of visual discrimination and a test of optomotor response, to identify glaucomatous DBA/2J mice. We then examine whether the elevation of intraocular pressure (IOP), the common risk factor for glaucoma, affects visual performances of the DBA/2J mice. We further compare the retinal ganglion cell death, one of the signature glaucoma symptoms, i...

2011-01-01

Purpurin is a key molecule for cell differentiation during the early development of zebrafish retina

British Library Electronic Table of Contents (United Kingdom)

Recently, we cloned purpurin cDNA as an upregulated gene in the axotomized fish retina. The retina-specific protein was secreted from photoreceptors to ganglion cell layer during an early stage of optic nerve regeneration in zebrafish retina. The purpurin worked as a trigger molecule for axonal regrowth in adult injured fish retina. During zebrafish development, purpurin mRNA first appeared in ventral retina at 2 days post-fertilization (dpf) and spread out to the outer nuclear layer at 3 dpf. Here, we investigated the role of purpurin for zebrafish retinal development using morpholino gene knockdown technique. Injection of purpurin morpholino into the 1-2 cell stage of embryos significantly inhibited the transcriptional and translational expression of purpurin at 3 dpf. In the purpurin mo...

2009-01-01

The Effect of Different Timber Harvesting Techniques on Plethadontid Salamander Populations.

Biodiversity of Costa Rican salamanders: Implications of high levels of genetic differentiation and phylogeographic structure for species formation

This investigation will explore the effect that current timber extraction techniques have on plethadontid salamander populations in ... group selection, and two-age harvest. Broad scale timber extraction can d...

HSP70, the earliest-induced gene in the zebrafish retina during optic nerve regeneration: Its role in cell survival

Although salamanders are characteristic amphibians in Holarctic temperate habitats, in tropical regions they have diversified evolutionarily only in tropical America. An adaptive radiation centered...Full Text Available

2000-02-15

British Library Electronic Table of Contents (United Kingdom)

Fish retinal ganglion cells (RGCs) can survive and regrow their axons after optic nerve injury. Injured RGCs express anti-apoptotic proteins, such as Bcl-2, after nerve injury; however, upstream effectors of this anti-apoptotic protein are not yet fully understood. Heat shock proteins (HSPs) play a crucial role in cell survival against various stress conditions. In this study, we focused on HSP70 expression in the zebrafish retina after optic nerve injury. HSP70 mRNA and protein levels increased rapidly 2.3-fold in RGCs by 1-6 h after injury and returned to control levels by 1-3 days. HSP70 transcription is regulated by heat shock factor 1 (HSF1). HSF1 mRNA and phosphorylated-HSF1 protein rapidly increased by 2.2-fold in RGCs 0.5-6 h after injury. Intraocular injection of HSP inhibitor I s...

2011-01-01

Ganglion Cysts

Medline Plus

... many bones. The bones are separated by special hinges called joints. Muscles make the bones move on ...

Traumatic retinal detachment.

Optical coherence tomography 3: automatic delineation of the outer neural retinal boundary and its influence on assessing retinal thickness measurement

Seventy-seven patients developed retinal breaks following an episode of ocular contusion, and 65 (84.4%) of these developed rhegmatogenous retinal detachment. Surgical treatment successfully restored...Full Text Available

1991-01-01

Coherency Effects on Retinal Neural Processes (ERG) of ...

No abstract prepared.

2004-07-01

Dissection of the sentry ganglion by laparoscopic boarding in patients with cervix uterine cancer clinical stages IA2 at IIB

... Accession Number : ADA111683. Title : Coherency Effects on Retinal Neural Processes (ERG) of Pseudemys. Descriptive ...

1981-12-01

International Nuclear Information System (INIS)

The obtained results in presently study demonstrate that the feasibility of the detection of the sentry ganglion in cervix uterine cancer using a boarding by laparoscopic via, being necessary the use of twice labelled as much with patent blue and radioisotope (colloid of labelled rhenium with "9"9"mTc, total dose of 3 MCi) to achieve the identification of the ganglion. (Author)

2005-05-04

Mutation Spectrum of EYS in Spanish Patients with Autosomal Recessive Retinitis Pigmentosa

Astrocyte-Derived Vascular Endothelial Growth Factor Stabilizes Vessels in the Developing Retinal Vasculature

Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal dystrophies characterised ultimately by the loss of photoreceptor cells. We have recently identified a new gene (EYS) encoding...Full Text Available

2010-11-01

Retinoids for Treatment of Retinal Diseases

Vascular endothelial growth factor (VEGF) plays a critical role in normal development as well as retinal vasculature disease. During retinal vascularization, VEGF is most strongly expressed by not yet...Full Text Available

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Misfolded Proteins and Retinal Dystrophies

Knowledge about retinal photoreceptor signal transduction and the visual cycle required for normal eyesight has expanded exponentially over the past decade. Substantial progress in human genetics...Full Text Available

2010-06-01

Increased M?ller Cell De-Differentiation After Grafting of Retinal Stem Cell in the Sub-Retinal Space of Royal College of Surgeons Rats

Many mutations associated with retinal degeneration lead to the production of misfolded proteins by cells of the retina. Emerging evidence suggests that these abnormal proteins cause cell death...Full Text Available

2010-01-01

British Library Electronic Table of Contents (United Kingdom)

In several vertebrate classes, the M?ller glia are capable of de-differentiating, proliferating, and acquiring a progenitor-like state in response to acute retinal injury or in response to exogenous growth factors. Our previous study has shown that M?ller cells can be activated and de-differentiated into retinal progenitors during Royal College of Surgeons (RCS) rats' degeneration, although the limited proliferation cannot maintain retinal function. We now report that rat retinal stem cells (rSCs) transplanted into RCS rats slowed the progression of retinal morphological degeneration and prevented the functional disruption. Further, we found that retinal progenitor cells labeled with Chx10 were increased significantly after rSCs transplantation, and most of them are mainly from activated M...

2011-01-01

Foveomacular retinitis.

Foveo-macular retinitis, solar retinopathy, and trauma.

A group of patients is described who developed the clinical features of foveomacular retinitis. No causative factors were isolated, and all patients strongly denied any type of sun gazing. It is possible...Full Text Available

1986-11-01

Study of epileptiform activity in cerebral ganglion of mud crab Scylla serrata

Three patients are described with foveal lesions resembling minute holes following trauma. The similarity of the lesions to foveomacular retinitis and solar retinopathy suggests that all these conditions...Full Text Available

1978-08-01

British Library Electronic Table of Contents (United Kingdom)

An attempt is made to induce in mud crab (Scylla serrata) epileptiform activities that resemble the generalized epileptic seizures. Cerebral ganglion of crab was exposed in situ, to a convulsant drug pentylenetetrazole (PTZ) 100?mM, for induction of seizures. Also, crabs were pretreated with antiepileptic drug viz sodium valproate (120??mol/l) to inhibit epileptiform activities. The surface electrical discharges of cerebral ganglion were recorded using Unkelscope (MIT, USA) in control as well as experimental animals. The cerebral ganglion of crab showed a pattern of high cerebral electrical discharges after PTZ treatment compared to control. The sodium valproate promoted sedative action in control and prevented PTZ-mediated epileptiform discharges. Glutamate and GABA contents in cerebral g...

2011-01-01

Retinal Nerve Fiber Layer Thickness Analysis in Early Glaucoma

Optic nerve head topographic measurements and retinal nerve fiber layer thickness in physiologic large cups.

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2008-07-01

Intravitreal bevacizumab for the treatment of neovascular glaucoma associated with central retinal artery occlusion.

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2005-09-01

Electrical properties of retinal electrode interface

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2009-09-01

Combined Central Retinal Vein and Artery Occlusion After Retrobulbar Anesthesia: A Case Report

A critical element of a retinal prosthesis is the stimulating electrode array, which is placed in close proximity to the retina. It is via this retinal-electrode interface that a retinal prosthesis electrically stimulates nerve cells to produce the perception of light. The impedance load seen by the current driver consists of the tissue resistance and the complex electrode impedance. The results in this paper show that the tissue resistance of the retina is significantly greater than that of the vitreous humor in the eye. Circuit models of the electrode-retina interface are used to parameterize the different contributors to the overall impedance.

2007-03-01

Bilateral retinal dysplasia and secondary glaucoma associated with homozygous protein C deficiency.

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2008-06-01

Acute Angle-Closure Glaucoma from Spontaneous Massive Hemorrhagic Retinal Detachment

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2005-06-01

CT-guided injection for ganglion impar blockade: a radiological approach to the management of coccydynia

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International Nuclear Information System (INIS)

Aim: To evaluate the role of computed tomography (CT) in needle placement for ganglion impar blocks, and to determine the efficacy of CT-guided ganglion impar blocks in the management of coccydynia. Materials and methods: The results of ganglion impar blockade in eight patients with coccydynia secondary to trauma or unknown cause were reviewed. The diagnosis of coccydynia was based on clinical history, location of pain, and response to previous diagnostic and therapeutic procedures. The eight patients were treated with CT-guided ganglion impar blocks to manage their coccyx pain after conservative procedures, including oral medication and cushions, failed to provide relief. All patients were subjected to ganglion impar blocks under a thin-section CT-guided technique for needle placement, using a mixture of bupivacaine and triamcinolone. The patients were followed-up for a period of ...

2010-01-01

Electrophysiological differences between nociceptive and non-nociceptive dorsal root ganglion neurones in the rat in vivo

Advancing Age Alters the Contribution of Calcium Release From Smooth Endoplasmic Reticulum Stores in Superior Cervical Ganglion Cells

Intracellular recordings were made from 1022 somatic lumbar dorsal root ganglion (DRG) neurones in anaesthetized adult rats, classified from dorsal root conduction velocities (CVs) as C, Aδ...Full Text Available

2005-06-15

Retinal nerve fiber hypertrophy in ataxia of Charlevoix-Saguenay patients

In superior cervical ganglion (SCG) neurons calcium-induced calcium release (CICR), mediated by ryanodine receptors (RyRs), contributes to stimulation-evoked intracellular calcium ([Ca²⁺]_i)...Full Text Available

2009-01-01

Retinal Fundus Image Registration via Vascular Structure Graph Matching

PurposeTo present full ophthalmologic examination and retinal nerve fiber layer (RNFL) photographs of autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) patients...Full Text Available

Reading strategies in Stargardt's disease with foveal sparing

Motivated by the observation that a retinal fundus image may contain some unique geometric structures within its vascular trees which can be utilized for feature matching, in this paper, we proposed...Full Text Available

2010-01-01

Progression of Neuronal and Synaptic Remodeling in the rd10 Mouse Model of Retinitis Pigmentosa

BackgroundSubjects with a ring scotoma can use two retinal loci, a foveal and a peripheral, for reading. Our aim was to investigate the relative use of both retinal loci as a function...Full Text Available

Non-Invasive Stem Cell Therapy in a Rat Model for Retinal Degeneration and Vascular Pathology

The Pde6b^rd10 (rd10) mouse has a moderate rate of photoreceptor degeneration and serves as a valuable model for human autosomal recessive retinitis pigmentosa...Full Text Available

2010-06-01

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Mutation analysis of 272 Spanish families affected by autosomal recessive retinitis pigmentosa using a genotyping microarray

BackgroundRetinitis pigmentosa (RP) is characterized by progressive night blindness, visual field loss, altered vascular permeability and loss of central vision. Currently there...Full Text Available

Macular and retinal nerve fiber layer thickness in Japanese measured by Stratus optical coherence tomography

PurposeRetinitis pigmentosa (RP) is a genetically heterogeneous disorder characterized by progressive loss of vision. The aim of this study was to identify the causative mutations...Full Text Available

Loss of lysophosphatidylcholine acyltransferase 1 leads to photoreceptor degeneration in rd11 mice

The purpose of this study was to determine the thickness of the macula and the retinal nerve fiber layer (RNFL) in Japanese subjects by Stratus optical coherence tomography (OCT), and to compare the...Full Text Available

2007-06-01

Intravitreal Avastin for Choroidal Neovascularization Associated with Stargardt-Like Retinal Abnormalities in Pseudoxanthoma Elasticum

Retinal degenerative diseases, such as retinitis pigmentosa and Leber congenital amaurosis, are a leading cause of untreatable blindness with substantive impact on the quality of life of affected individuals...Full Text Available

2010-08-31

Identification of genetic variation and haplotype structure of the canine ABCA4 gene for retinal disease association studies

The aim of the study was to describe a patient with pseudoxanthoma elasticum (PXE), showing Stargardt-like retinal abnormalities, who underwent treatment with intravitreal bevacizumab for subfoveal...Full Text Available

2010-10-01

Gene Therapy in the Retinal Degeneration Slow Model of Retinitis Pigmentosa

Over 200 mutations in the retina specific member of the ATP-binding cassette transporter super-family (ABCA4) have been associated with a diverse group of human retinal diseases....Full Text Available

2010-10-01

Experimental Approaches to the Study of A2E, a Bisretinoid Lipofuscin Chromophore of Retinal Pigment Epithelium

Human blinding disorders are often initiated by hereditary mutations that insult rod and/or cone photoreceptors and cause subsequent cellular death. Generally, the disease phenotype can be predicted...Full Text Available

2010-01-01

Effects of Age on Optical Coherence Tomography Measurements of Healthy Retinal Nerve Fiber Layer, Macula and Optic Nerve Head

Bisretinoid lipofuscin compounds that accumulate in retinal pigment epithelial (RPE) cells are implicated in the pathogenesis of some forms of macular degeneration. In the development of approaches...Full Text Available

2010-01-01

Comprehensive SNP-chip for retinitis pigmentosa-Leber congenital amaurosis diagnosis: new mutations and detection of mutational founder effects

PurposeTo determine the effects of age on global and sectoral peripapillary retinal nerve fiber layer (RNFL), macular thicknesses and optic nerve head (ONH) parameters...Full Text Available

2009-06-01

A2e mediated phototoxic effects of endoilluminators

Fast and efficient high-throughput techniques are essential for the molecular diagnosis of highly heterogeneous hereditary diseases, such as retinitis pigmentosa (RP). We had previously approached RP...Full Text Available

2010-01-01

A decrease in retinal progenitor cells is associated with early features of diabetic retinopathy in a model that combines diabetes and hypertension

AimsTo compare the theoretical retinal threshold time for endoilluminators and experimental phototoxic effect using A2e laden retinal pigment epithelial (RPE) cells.MethodsThe...Full Text Available

2006-02-01

A comparative study between intravitreal triamcinolone and bevacizumab for macular edema due to central retinal vein occlusion with poor vision

PurposeHyperglycemia and hypertension contribute to the development of diabetic retinopathy, and this may involve alterations in the normal retinal cell cycle. In this work, we examined...Full Text Available

Electrical properties of retinal-electrode interface.

Aim:To compare the effect of intravitreal bevacizumab and triamcinolone in patients with macular edema after central retinal vein occlusion (CRVO), presenting with poor...Full Text Available

2011-03-01

Homozygosity Mapping Reveals Null Mutations in FAM161A as a Cause of Autosomal-Recessive Retinitis Pigmentosa

2007-02-20

Mapping neuropeptide expression by mass spectrometry in single dissected identified neurons from the dorsal ganglion of the nematode Ascaris suum

Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal degenerations caused by mutations in at least 45 genes. Using homozygosity mapping, we identified a ∼4 Mb homozygous region...Full Text Available

2010-09-10

Expression of leukotriene receptors in the rat dorsal root ganglion and the effects on pain behaviors

We have developed a method for dissecting single neurons from the nematode Ascaris suum, in order to determine their peptide content by mass spectrometry (MS). In this paper,...Full Text Available

2010-07-21

Relationship between the retinal thickness analyzer and the GDx VCC scanning laser polarimeter, Stratus OCT optical coherence tomograph, and Heidelberg retina tomograph II confocal scanning laser ophthalmoscopy.

BackgroundLeukotrienes (LTs) belong to the large family of lipid mediators implicated in various inflammatory conditions such as asthma and rheumatoid arthritis. Four distinct types...Full Text Available

Mitochondrial Potassium ATP Channels and Retinal Ischemic Preconditioning

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2008-03-01

Intraocular coenurosis: a case report.

PURPOSETo examine the mechanisms of ischemic preconditioning (IPC) related to the opening of mitochondrial KATP (mKATP) channels in the retina.Full Text Available

2006-05-01

PI3K/Akt and mTOR/p70S6K Pathways Mediate Neuroprotectin D1-Induced Retinal Pigment Epithelial Cell Survival during Oxidative Stress-Induced Apoptosis

A case of intraocular coenurosis was clinically diagnosed and treated with praziquantel. The drug destroyed the coenurus, but vision was lost through toxic endophthalmitis and retinal detachment. There...Full Text Available

1991-07-01

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Neuroprotectin D1/Protectin D1 Stereoselective and Specific Binding With Human Retinal Pigment Epithelial Cells and Neutrophils

The initiation and progression of several forms of retinal degenerations involve excessive, repetitive, and/or sustained oxidative stress that, in turn, mediate photoreceptor cell damage and...Full Text Available

2010-06-01

Interaction of Extracellular Domain 2 of the Human Retina-specific ATP-binding Cassette Transporter (ABCA4) with All-trans-retinal*

Retinal pigment epithelial (RPE) cells, derived from the neuroectoderm, biosynthesize the novel lipid mediator neuroprotectin D1 (NPD1) from docosahexaenoic acid (DHA) in response to oxidative...Full Text Available

2010-01-01

Replacement of leucine-93 by alanine or threonine slows down the decay of the N and O intermediates in the photocycle of bacteriorhodopsin: Implications for proton uptake and 13-cis-retinal----all-trans-retinal reisomerization

The retina-specific ATP-binding cassette (ABC) transporter, ABCA4, is essential for transport of all-trans-retinal from the rod outer segment discs in the retina and is associated with...Full Text Available

2010-06-18

Roles of mitochondria and temperature in the control of intracellular calcium in adult rat sensory neurons

The authors report that the replacement of Leu-93 in bacteriorhodopsin by Ala (L93A) or Thr (L93T) slows down the photocycle by approximately 100-fold relative to wild-type bacteriorhodopsin. Time-resolved visible absorption spectroscopy and resonance Raman experiments, respectively, show the presence of long-lived O-like and N-like intermediates in the photocycles of the above mutants. We infer the existence of an equilibrium between the N and O intermediates in the photocycles of these mutants. The L93A and L93T mutants exhibit normal proton pumping under continuous illumination, suggesting that the decay of the N and/or O intermediate, and consequently, proton translocation, can be accelerated by the absorption of a second photon. Since the 13-cis----all-trans reisomerization of retinal is completed during the decay of the N and O intermediates, they conclude that the interaction of Leu-93 with retinal is important in this phase of the ...

1991-08-01

Discrimination between UTP- and P2-purinoceptor-mediated depolarization of rat superior cervical ganglia by 4,4'-diisothiocyanatostilbene-2,2'- disulphonate (DIDS) and uniblue A.

SUMMARYWe recorded Ca²⁺ current and intracellular Ca²⁺ ([Ca²⁺]_i) in isolated adult rat dorsal root ganglion (DRG) neurons at 20 and...Full Text Available

2008-04-01

High-Resolution Optical Coherence Tomography Findings in Solar Maculopathy and the Differential Diagnosis of Outer Retinal Holes

1. Using a grease-gap recording technique we have investigated the effects of some antagonists of P2-purinoceptors on the depolarization of the rat isolated superior cervical ganglion evoked by 100...Full Text Available

1995-06-01

British Library Electronic Table of Contents (United Kingdom)

PurposeTo characterize the morphology of outer retinal holes caused by solar maculopathy, using spectral-domain optical coherence tomography (SD-OCT). DesignThis study is an observational case series. MethodsThe SD-OCT findings of 3 patients (6 eyes) with chronic solar maculopathy are presented. ResultsSD-OCT demonstrates a characteristic appearance of partial-thickness hole(s) in the outer retina at the fovea. In 3 of 6 eyes, there is 1 hole directly beneath the umbo. In the remaining 3 eyes, there are multifocal holes spread across the fovea. Holes in more restricted layers, as had been previously reported with time-domain OCT, were not seen. In addition, advanced visualization of SD-OCT data demonstrates a hyperreflective ring around the outer retinal hole. ConclusionsSD-OCT can be used...

2011-01-01

X-ray structure of sensory rhodopsin II at 2.1-? resolution

Time course profiling of the retinal transcriptome after optic nerve transection and optic nerve crush

Sensory rhodopsins (SRs) belong to a subfamily of heptahelical transmembrane proteins containing a retinal chromophore. These photoreceptors mediate the cascade of vision in animal eyes and phototaxis...Full Text Available

2001-08-28

The ATP-Binding Cassette Transporter ABCA4: Structural and Functional Properties and Role in Retinal Disease

PurposeA time-course analysis of gene regulation in the adult rat retina after intraorbital nerve crush (IONC) and intraorbital nerve transection (IONT).MethodsRNA...Full Text Available

Temporal Interactions during Paired-Electrode Stimulation in Two Retinal Prosthesis Subjects

ATP-binding cassette transporters (ABC transporters) utilize the energy of ATP hydrolysis to translocate an unusually diverse set of substrates across cellular membranes. ABCA4, also known as...Full Text Available

2010-01-01

Rhythmic expression of an egr-1 transgene in rats distinguishes two populations of photoreceptor cells in the retinal outer nuclear layer

Purpose.Since 2002, six blind patients have undergone implantation of an epiretinal 4 × 4 electrode array designed to directly stimulate the remaining cells of the retina...Full Text Available

2011-01-01

Retinal channelrhodopsin-2-mediated activity in vivo evaluated with manganese-enhanced magnetic resonance imaging

PurposeNocturnal rhythms of gene expression in the retina are known to be both darkness- and circadian clock-dependent, but their role and cellular location are not well defined....Full Text Available

New retinal imaging for the visualization and analysis of vitreoretinal interface (VRI) by short-wavelength scanning laser ophthalmoscope (swSLO)

PurposeEctopic expression of light-sensitive proteins, such as channelrhodopsin-2, represent a novel approach for restoring light-detection capabilities to degenerated retina. A...Full Text Available

Macular abnormalities in the reattached retina.

Background:The purpose of the study was to evaluate vitreoretinal interface (VRI) alteration with a short-wavelength scanning laser ophthalmoscope (swSLO), the Nidek F-10, and compare...Full Text Available

2011-01-01

Long-term Retinal Function and Structure Rescue Using Capsid Mutant AAV8 Vector in the rd10 Mouse, a Model of Recessive Retinitis Pigmentosa

Sixty-six patients in whom the macula was detached before surgery were observed for at least 1 year after retinal reattachment. Macular abnormalities were recognised clinically in most patients with...Full Text Available

1978-09-01

British Library Electronic Table of Contents (United Kingdom)

The retinal degeneration 10 (rd10) mouse is a well-characterized model of autosomal recessive retinitis pigmentosa (RP), which carries a spontaneous mutation in the ? subunit of rod cGMP-phosphodiesterase (PDE?). Rd10 mouse exhibits photoreceptor dysfunction and rapid rod photoreceptor degeneration followed by cone degeneration and remodeling of the inner retina. Here, we evaluate whether gene replacement using the fast-acting tyrosine-capsid mutant AAV8 (Y733F) can provide long-term therapy in this model. AAV8 (Y733F)-smCBA-PDE? was subretinally delivered to postnatal day 14 (P14) rd10 mice in one eye only. Six months after injection, spectral domain optical coherence tomography (SD-OCT), electroretinogram (ERG), optomotor behavior tests, and immunohistochemistry showed tha...

2011-01-01

Inhibition of the visual cycle by A2E through direct interaction with RPE65 and implications in Stargardt disease

Fourier-Domain Optical Coherence Tomography and Adaptive Optics Reveal Nerve Fiber Layer Loss and Photoreceptor Changes in a Patient With Optic Nerve Drusen

Stargardt disease (STGD) is the major form of inherited juvenile macular degeneration. Pyridinium bis-retinoid A2E is a major component of lipofuscin which accumulates in retinal pigment epithelium...Full Text Available

2010-10-12

Crystallographic structure of xanthorhodopsin, the light-driven proton pump with a dual chromophore

BackgroundNew technology allows more precise definition of structural alterations of all retinal layers although it has not been used previously in cases of optic...Full Text Available

2008-06-01

Chapter 61: Photoreceptor Cell Degeneration in Abcr^?/? Mice

Homologous to bacteriorhodopsin and even more to proteorhodopsin, xanthorhodopsin is a light-driven proton pump that, in addition to retinal, contains a noncovalently bound carotenoid with a function...Full Text Available

2008-10-28

CLINICAL VALUE, NORMATIVE RETINAL SENSITIVITY VALUES, AND INTRASESSION REPEATABILITY USING A COMBINED SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY/SCANNING LASER OPHTHALMOSCOPE MICROPERIMETER

Mice harboring a null mutation in Abca4/Abcr serve as a model of autosomal recessive Stargardt disease. Consistent with the human retinal disorder, deficiency...Full Text Available

2010-01-01

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Mechanisms mediating the trophic effect of nerves during vertebrate limb regeneration

PurposeTo establish normative values for macular light sensitivity and to determine the intrasession fluctuation of perimetric responses using the OPKO/OTI microperimeter.Full Text Available

2011-02-01

Pseudophakic and aphakic retinal detachment mimicking cystoid macular edema.

Salamanders regenerate their appendages after amputation and nerves are required for this process. Experiments were designed to test the idea that one way nerves could affect blastema cell proliferation is by influencing the metabolism of extracellular matrix (ECM) components and to identify neurotrophic factors which promote blastema cell mitosis. Temporal and spatial differences of glycosaminoglycans (GAGs) synthesis is innervated and denervated limbs were examined. Hyaluronic acid (HA) was found to be the major GAG produced during the proliferative period and chondroitin sulfate during differentiation. Denervation reduced synthesis of both these components by half. Dorsal root ganglia and fibroblast growth factor (FGF), a brain-derived mitogen, similarly doubled GAG synthesis in cultured blastemas, the FGF-effect being primarily on HA production. Histochemical and autoradiographical results confirmed the biochemical data. Autoradiography of the limb tissue ...

1986-01-01

Celastrol regulates innate immunity response via NF-@kB and Hsp70 in human retinal pigment epithelial cells

Seventeen eyes of patients who were being followed by their ophthalmologists for aphakic (8 eyes) or pseudophakic (9 eyes) cystoid macular edema (CME) were examined on referral. All eyes showed retinal detachment (RD), and eight eyes had CME with RD. Most RDs were inferior and shallow. Proliferative vitreoretinopathy (PVR) was noted in 15 eyes (88.2%). There was history of vitreous loss during the last intraocular surgery in 88.2% eyes. Visual acuity ranged from 20/40 to hand movements. Fundus view was hazy in most eyes, and indirect ophthalmoscopy was most useful in detecting RD. Retinal reattachment with scleral buckling and/or vitrectomy was achieved in 16 eyes (94.1%). Postoperative visual recovery was jeopardized due to longstanding macular detachment of greater than 1 month in 11 eyes (64.7%). Eight eyes (47%) achieved 20/50 vision whereas 25% did not improve to better than 20/400. Factors leading to failure in making the correct ...

1987-07-01

British Library Electronic Table of Contents (United Kingdom)

Elevated nuclear factor kappa B (NF-@kB) activity and interleukin-6 (IL-6) secretion participates in the pathology of several age and inflammatory-related diseases, including age-related macular degeneration (AMD), in which retinal pigment epithelial cells are the key target. Recent findings reveal that heat shock protein 70 (Hsp70) may affect regulation of NF-@kB. In the current study, effects of Hsp70 expression on NF-@kB RelA/p65 activity were evaluated in human retinal pigment epithelial cells (ARPE-19) by using celastrol, a novel anti-inflammatory compound. Anti-inflammatory properties of celastrol were determined by measuring expression levels of IL-6 and endogenous NF-@kB levels during lipopolysaccharide (LPS) exposure by using enzyme-linked immunosorbent assays (ELISA). Cell viabil...

2011-01-01

Ultraviolet-B Phototoxicity and Hypothetical Photomelanomagenesis: Intraocular and Crystalline Lens Photoprotection

British Library Electronic Table of Contents (United Kingdom)

Purpose Ultraviolet-B (UV-B) radiation can cause phototoxic macular injuries in young people who have been sunbathing but not sungazing and in welders. Welders have a reportedly increased risk of uveal melanoma. We analyze phakic and pseudophakic risks for solar and welding arc UV-B exposure. Design Optical radiation measurement, analysis, and perspective. Methods Spectral transmittances were measured for UV-transmitting, UV-blocking, and blue-blocking intraocular lenses (IOLs). The photoprotective performances of crystalline and intraocular lenses were analyzed using relevant epidemiologic and laboratory data and action spectra for acute retinal phototoxicity and melanoma photocarcinogenesis. Results Crystalline lens UV-B retinal protection is deficient in children and young adults, incre...

2010-01-01

Serotonin Inhibits Protein Feeding in the Blow Fly, Phormia regina (Meigen)

British Library Electronic Table of Contents (United Kingdom)

Serotonin is an important signaling molecule involved in the control of feeding in flies and other animals. In this study, a potential neurohemal release site for serotonin and the effects of exogenous serotonin on protein feeding were examined in the black blow fly, Phormia regina. A dense network of varicose neural processes exhibiting serotonin-like immunoreactivity was identified on the dorsal region of the thoracico-abdominal ganglion in P. regina. This dorsal region of the central nervous system is a likely site for the release of serotonin into the hemolymph. Circulating serotonin may have multiple systemic effects on fly physiology, including modulating or regulating feeding related processes and diuresis. Injections of exogenous serotonin reduced protein meal size in female flies ...

2009-01-01

Protein expression following heat shock in the nervous system of Locusta migratoria

British Library Electronic Table of Contents (United Kingdom)

There is a thermal range for the operation of neural circuits beyond which nervous system function is compromised. Locusta migratoria is native to the semiarid regions of the world and provides an excellent model for studying neural phenomena. In this organism previous exposure to sublethal high temperatures (heat shock, HS) can protect neuronal function against future hyperthermia but, unlike many organisms, the profound physiological adaptations are not accompanied by a robust increase of Hsp70 transcript or protein in the nervous system. We compared Hsp70 increase following HS in the tissues of isolated and gregarious locusts to investigate the effect of population density. We also localized Hsp70 in the metathoracic ganglion (MTG) of gregarious locusts to determine if HS affects Hsp70 ...

2011-01-01

Silver nanoparticles inhibit VEGF-and IL-1?-induced vascular permeability via Src dependent pathway in porcine retinal endothelial cells

Model for predicting the effects of laser exposures and eye protection on vision. Interim report, January 1989-January 1990

The aim of this study is to determine the effects of silver nanoparticles (Ag-NP) on vascular endothelial growth factor (VEGF)-and interleukin-1 beta (IL-1β)-induced vascular permeability, and...Full Text Available

Immunohistochemical localization of low density lipoprotein receptor-related protein 1 and ?₂-Macroglobulin in retinal and choroidal tissue of proliferative retinopathies

Laser safety standards and eye protection (filters) are designed to limit ocular exposures to prevent retinal lesions, yet eyesafe laser exposures can disrupt vision by causing glare and flashblindness. Protective filters can have opposing effects on vision function. They reduce laser exposures but also reduce task luminance and contrast. Filters alone may interfere with vision and consequently reduce work safety and performance. It is therefore important to be able to predict the effects of both laser exposures and protective filters to assess trade-offs between protection and visual function. This paper briefly reviews the methods, concepts, and experimental database used in our laboratory to predict laser, filter, and laser-plus-filter effects on tasks involving visual detection. The modeling approach uses estimates of the spatial distribution of light in the retinal image of the laser source to predict glare, flashblindness, and ...

1990-01-01

Visible-light resin-curing units: retinal hazards and protective lenses. Final report, December 1982-May 1986

The immunolocalization of the low density lipoprotein receptor-related protein 1 (LRP1) and its ligand alpha 2-Macroglobulin (α₂M) was examined in tissues from human donor...Full Text Available

2010-08-01

Benzyl carbamyl analogue of lignocaine: vasodepressor mechanism of action.

The potential retinal hazard of dental visible-light photopolymerization units and the efficacy of protective lenses for reducing the potential hazards were assessed. The spectral radiance profiles of 11 visible-light photopolymerization units were measured; and the results were then weighted according to the American Conference of Governmental Industrial Hygienists (ACGIH) Blue Light and Thermal Hazard Functions. The results indicate that there are no thermal hazards to the retina even for the worst case condition. None of the blue-light hazard maximum permissible exposure times is short enough to be of concern unless the individual operator chooses to focus on the light source for an extended period. Those individuals who elect to stare at the light during curing procedures should consider the purchase of protective lenses. The special transmission profiles of 16 protective lenses were measured and new permissible exposure limits calculated for each lens/unit ...

1986-11-01

In vitro MRI of brain development

1. The benzyl carbamyl analogue of lignocaine [2-(diethylaminoacetamido)-3-carbamyl-4-methyl-5-benzylpyrrole] at an intravenous dose of 4 mg/kg caused a blood pressure decrease of 54 mmHg. 2. A greater hypotensive effect was observed in hypertensive compared to normotensive animals. Anaesthesia magnified the vasodepressor effect in both groups. 3. The analogue did not possess centrally-mediated effects on blood pressure but exerted its hypotensive effect via a peripheral mechanism. 4. The analogue produced a relaxant effect on intestinal and vascular smooth muscle while exerting minimal effects on muscarinic, sympathetic, or ganglionic nicotinic receptors. 5. The analogue exhibited less cardiac depressant action on left ventricular rate (dp/dt) and force of contraction than lignocaine. 6. Lethal effects for the analogue were first observed at 16 mg/kg following intravenous administration and at 500 mg/kg following intraperitoneal administration. 7. In conclusion, ...

International Nuclear Information System (INIS)

In this review, we demonstrate the developmental appearance, structural features, and reorganization of transient cerebral zones and structures in the human fetal brain using a correlative histological and MRI analysis. The analysis of postmortem aldehyde-fixed specimens (age range: 10 postovulatory weeks to term) revealed that, at 10 postovulatory weeks, the cerebral wall already has a trilaminar appearance and consists of: (1) a ventricular zone of high cell-packing density; (2) an intermediate zone; (3) the cortical plate (in a stage of primary consolidation) with high MRI signal intensity. The anlage of the hippocampus is present as a prominent bulging in the thin limbic telencephalon. The early fetal telencephalon impar also contains the first commissural fibers and fornix bundles in the septal area. The ganglionic eminence is clearly visible as an expanded continuation of the proliferative ventricular zone. The basal ganglia showed an initial aggregation of ...

2006-02-01

Vitrectomy Timing for Retained Lens Fragments After Surgery for Age-Related Cataracts: A Systematic Review and Meta-Analysis

British Library Electronic Table of Contents (United Kingdom)

PurposeTo evaluate the effect of vitrectomy timing on outcomes for patients with crystalline retained lens fragments receiving vitrectomy 3+ days after cataract surgery. DesignSystematic review and meta-analysis of retrospective interventional cases series. MethodsSearches of MEDLINE (English, 1/1/85 through 7/30/2010) and article reference lists. Articles were screened for patients with crystalline retained lens fragments after surgery for age-related cataracts, discussion of vitrectomy timing, and, for the meta-analysis, patient totals for at least 1 outcome and multiple time periods, 10+ patients, and mean follow-up ?3 months. Outcomes included visual acuity, retinal detachment, increased intraocular pressure, intraocular infection/inflammation, cystoid macular edema, and corneal...

2011-01-01

Photoreceptor Inner and Outer Segment Defects in Myopic Foveoschisis

British Library Electronic Table of Contents (United Kingdom)

PurposeTo evaluate pathologic features of the photoreceptors in myopic foveoschisis with the Fourier-domain optical coherence tomography (FD-OCT).DesignObservational case series.MethodsSeventeen eyes of 15 patients with myopic foveoschisis (foveal detachment type, six eyes; foveoschisis type, 11 eyes) were included. We observed the photoreceptor inner and outer segments (IS/OS) and evaluated the morphologic status using FD-OCT. Fundus photographs and time-domain OCT (TD-OCT) images also were obtained.ResultsIS/OS defects, which are uncommon in retinal detachments in eyes with myopia, were seen clearly in five eyes (three eyes [50%] with the foveal detachment type; two eyes [18%] with the foveal schisis type). Fundus photographs showed myopic chorioretinal atrophy in eight study eyes (47%),...

2008-01-01

Optimal Dynamical Range of Excitable Networks at Criticality

CERN Document Server

A recurrent idea in the study of complex systems is that optimal information processing is to be found near bifurcation points or phase transitions. However, this heuristic hypothesis has few (if any) concrete realizations where a standard and biologically relevant quantity is optimized at criticality. Here we give a clear example of such a phenomenon: a network of excitable elements has its sensitivity and dynamic range maximized at the critical point of a non-equilibrium phase transition. Our results are compatible with the essential role of gap junctions in olfactory glomeruli and retinal ganglionar cell output. Synchronization and global oscillations also appear in the network dynamics. We propose that the main functional role of electrical coupling is to provide an enhancement of dynamic range, therefore allowing the coding of information spanning several orders of magnitude. The mechanism could provide a microscopic neural basis for psychophysical laws.

2006-01-01

KMeyeDB: a graphical database of mutations in genes that cause eye diseases

British Library Electronic Table of Contents (United Kingdom)

KMeyeDB () is a database of human gene mutations that cause eye diseases. We have substantially enriched the amount of data in the database, which now contains information about the mutations of 167 human genes causing eye-related diseases including retinitis pigmentosa, cone-rod dystrophy, night blindness, Oguchi disease, Stargardt disease, macular degeneration, Leber congenital amaurosis, corneal dystrophy, cataract, glaucoma, retinoblastoma, Bardet-Biedl syndrome, and Usher syndrome. KMeyeDB is operated using the database software MutationView, which deals with various characters of mutations, gene structure, protein functional domains, and polymerase chain reaction (PCR) primers, as well as clinical data for each case. Users can access the database using an ordinary Internet browser wi...

2010-01-01

Comparison of 25- and 23-gauge sutureless microincision vitrectomy surgery in the treatment of various vitreoretinal diseases

British Library Electronic Table of Contents (United Kingdom)

PurposeTo compare the effectiveness and safety of 25- and 23-gauge sutureless microincision vitrectomy surgery (MIVS) in the management of various vitreoretinal diseases.MethodsEighty-five consecutive patients undergoing sutureless vitrectomy during January to April 2008 were randomized to either 25- or 23-gauge MIVS. Data collected prospectively included best-corrected visual acuity (BCVA), operation time, postoperative visual recovery, postoperative anterior segment change, and complications.ResultsThe most common indications for MIVS were macular hole, macular pucker, vitreous haemorrhage, and diabetic traction retinal detachment. Mean operation times of the 25-gauge (n=38) and 23-gauge groups (n=47) were 33.68 and 34.47?min, respectively (P=0.942). Mean BCVA improved significantl...

2010-01-01

Arterial and venous thrombosis in patients with von Willebrand?s disease: A critical review of the literature

British Library Electronic Table of Contents (United Kingdom)

All patients with von Willebrand?s disease (vWD) who showed an arterial or venous thrombosis and were reported in the literature have been evaluated. 11 patients had arterial thrombosis while 19 had venous thrombosis for a total of 30 cases. 9 out the 11 cases with arterial thrombosis had myocardial infarction. Two had cerebral thrombosis. Associated risk factors for arterial thrombosis were available only for three patients who showed, respectively, smoking and dyslipidemia (2 cases) and smoking and intravenous desmopressin infusion (1 case). The majority of patients with venous thrombosis showed DVT with or without PE. Four patients presented with apparently isolated PE. In two instances thrombosis occurred in unusual sites (central retinal vein and portal vein, respectively). Several as...

2006-01-01

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Pioglitazone does not affect vascular or inflammatory responses after endotoxemia in humans.

Late-onset Stargardt-like macular dystrophy maps to chromosome 1p13

PPARgamma agonists have been proposed to exert more than metabolic benefits, particularly by anti-inflammatory mechanisms. We hypothesized that pioglitazone might modulate inflammatory and vascular responses to lipopolysaccharide (LPS). In a placebo-controlled parallel-group study in 18 healthy male subjects, the E. coli endotoxin model of inflammation (20 IU/kg i. v.) was employed to test the effect of 60 mg pioglitazone over nine days on inflammatory cytokines. Macrovascular function and microvascular blood flow were assessed by brachial artery ultrasound and retinal blood flow parameters, respectively. Pioglitazone increased brachial artery diameter by 5.6% but had no effect on other outcome parameters under resting conditions. LPS increased cytokine levels to peak concentrations of 91.3+/-22.5 ng/ml (IL-6), 261.4+/-60.0 ng/ml (TNFalpha), and 524.5+/-15.3 ng/ml (VCAM-1). The endotoxin caused microvascular vasodilation and increased retinal ...

2008-05-21

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Localisation of the neuropeptide PACAP and its receptors in the rat parathyroid and thyroid glands.

Stargardt`s disease (MIM 248200), originally described in 1909, is an autosomal recessive condition of childhood, characterized by a sudden and bilateral loss of central vision. Typically, it has an early onset (7 to 12 years), a rapidly progressive course and a poor final outcome. The central area of the retina (macula) displays pigmentary changes in a ring form with depigmentation and atrophy of the retinal pigmentary epithelium (RPE). Perimacular yellowish spots, termed fundus flavimaculatus, are observed in a high percentage of patients. We have recently reported the genetic mapping of Stargardt`s disease to chromosome 1p13. On the other hand, considering that fundus flavimaculatus (MIM 230100) is another form of fleck fundus disease, with a Stargardt-like retinal aspect but with a late-onset and a more progressive course, we decided to test the hypothesis of allelism between typical Stargardt`s disease and late-onset autosomal recessive ...

1994-09-01

102

Rhodopsin photochemistry is vibrationally coherent

PACAP (pituitary adenylate cyclase activating polypeptide) is widely distributed neuropeptide acting via three subtypes of receptors, PAC(1), VPAC(1) and VPAC(2). Here we examined the localisation and nature of PACAP-immunoreactive nerves in the rat thyroid and parathyroid glands and defined the distribution of PAC(1), VPAC(1) and VPAC(2) receptor mRNA's. In the parathyroid gland a large number of nerve fibres displaying PACAP-immunoreactivity were distributed beneath the capsule, around blood vessels and close to glandular cells. Most of the PACAP-nerves were sensory, since they co-stored CGRP (calcitonin-gene-related peptide) and were sensitive to capsaicin-treatment. mRNA's for PAC(1) and VPAC(2) receptors occurred in the parathyroid gland, mainly located in the glandular cells. In the thyroid gland PACAP-immunoreactive nerve fibres were associated with blood vessels, thyroid follicles and parafollicular C-cells. A high degree of co-existence between PACAP and VIP (vasoactive ...

2010-12-19

103

Evaluation of a convenient method of assessing rodent visual function in safety pharmacology studies: Effects of sodium iodate on visual acuity and retinal morphology in albino and pigmented rats and mice

Visual excitation is initiated by the absorption of a photon by the 11-cis retinal chromophore bound within the pigment called rhodopsin. We have used a variety of vibrational spectroscopies to obtain information about the vibrational nuclear dynamics that lead to this efficient photochemical isomerization. The cis-trans isomerization in rhodopsin is complete in only 200 fs. The extreme speed of this process, which is consistent with the {approximately}50 fs lifetime indicated by the spontaneous emission yield, suggests that the photochemistry involves non-stationary states or vibrational coherence. Recent studies have in fact observed vibrationally coherent oscillations of the ground state photoproduct called bathorhodopsin following impulsive excitation of the rhodopsin reactant. This conclusively demonstrates that the isomerization process in rhodopsin is vibrationally coherent. These observations further suggest that the isomerization quantum yield is directly ...

1995-12-31

104

British Library Electronic Table of Contents (United Kingdom)

Introduction: We have evaluated the ability of a semi-automated, optomotor reflex method to assess drug-induced visual dysfunction, in albino and pigmented rats and mice. Methods: Male Han Wistar (HW) and Long Evans (LE) rats and mice (CD-1 and C57BL/6) were tested in a chamber formed by 4 computer monitors displaying a rotating vertical grating, to elicit head-tracking movements. The highest visible grating frequency was taken as the threshold of visual acuity, in cycles per degree (c/d). Animals received an intravenous infusion of either sodium iodate (50mg/kg) or 0.9% w/v NaCl (aq). They were tested 2h later, then re-tested daily for a further 3days. The time course of the effect was assessed in HW rats over a 6-week period, including electron microscopy, and immunohistochemical analysi...

2011-01-01

105

A YAC contig encompassing the recessive Stargardt disease gene (STGD) on chromosome 1p

Quantitative pharmacological analysis of 2-125I-iodomelatonin binding sites in discrete areas of the chicken brain

Stargardt disease (STGD) and fundus flavimaculatus are infrequent autosomal recessive conditions characterized by a juvenile macular dystrophy and variable degrees of peripheral retinal changes. Linkage analysis performed in 47 STGD/fundus flavimaculatus families demonstrated significant linkage to 13 polymorphic DNA markers on chromosome 1p. The maximum combined two-point lod score was 32.7 (maximum recombination fraction [{theta}{sub max}] = .006) with the polymorphic marker D1S188. Our data demonstrate that STGD and fundus flavimaculatus are the same disorder clinically and genetically and provide further evidence for genetic homogeneity of this phenotype. Analysis of recombination on disease chromosomes placed the STGD gene within a 4-cM interval between markers D1S435 and D1S236. A physical map was constructed of a YAC contig flanking STGD, from markers D1S500 to D1S495, and includes the critical interval delineated by historical recombinants. This contig ...

1995-12-01

106

Predictive model of electron-beam-induced flashblindness. Final report, November 1983-October 1984

The authors have localized and characterized 2-125I-iodomelatonin binding sites in the chicken brain using in vitro quantitative autoradiography. Binding sites were widely distributed throughout the chicken brain, predominantly in regions associated with the visual system. The specific binding of 2-125I-iodomelatonin to discrete chicken brain areas was found to be saturable, reversible, and of high affinity. The specific binding of 2-125I-iodomelatonin (75 pm) was quantitated for 40 identifiable brain regions. Eight brain regions were chosen for binding characterization and pharmacological analysis: optic tectum, Edinger-Westphal nucleus, oculomotor nucleus, nucleus rotundus, ventral supraoptic decussation, ventrolateral geniculate nucleus, neostriatum, and ectostriatum. These regions showed no rostral-caudal gradient in 2-125I-iodomelatonin specific binding, and saturation analysis revealed a single class of high-affinity sites with KD values in the range of 33-48 pM and receptor site ...

1991-09-01

107

Consistency of ocular coherence tomography fast macular thickness mapping in diabetic diffuse macular edema

The spectral characteristics of the Cherenkov radiation have been evaluated and converted to equivalent retinal irradiance from external sources. On the basis of the conversion, electron fluxes have been estimated for 2-sec recovery times from flashblindness. The electrons are assumed to have energies greater than 6 MeV and to be delivered in one or more bursts of 1 microsecond each over 1 sec. It is important to note that very little data exists on recovery times as short as 2 sec for either photopic and scotopic conditions. This situation is a direct result of the lack of definition of the critical tasks and their sensitivity to an interruption of background adaptation. The Cherenkov radiation produced within the eye by relativistic electrons can be compared to light from external sources by the relationships: 1 rad approx. = 4.6 scotopic td-sec and 1 rad approx. = 0.55 photopic td sec. Based on these conversion factors, the following estimates can be derived by ...

1985-03-01

108