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Samson James Daniel - - 2011
Noise exposure is a major cause of hearing loss. Classical methods of studying protein involvement have provided a basis for understanding signaling pathways that mediate hearing loss and damage repair but do not lend themselves to studying large networks of proteins that are likely to increase or decrease during noise ...
Shimono Masanori - - 2011
We investigated the key anatomical structures mediating interhemispheric integration during the perception of apparent motion across the retinal midline. Previous studies of commissurotomized patients suggest that subcortical structures mediate interhemispheric transmission but the specific regions involved remain unclear. Here, we exploit interindividual variations in the propensity of normal subjects to ...
Ahn Sung Dae - - 2011
White organic light-emitting devices (WOLEDs) were fabricated utilizing a mixed color-conversion layer consisting of CaAl12O19:Mn and Zn2SiO4:Mn phosphors. The ratio between the CaAl12O19:Mn and the Zn2SiO4:Mn phosphor determined the rate of the red and the green lights. The color rendering index was improved by using a mixed color-conversion phosphor layer.
Moeller Trevor - - 2010
A variation of a hanging pendulum thrust stand capable of measuring the performance of an electric thruster operating in the vertical orientation is presented. The vertical orientation of the thruster dictates that the thruster must be horizontally offset from the pendulum pivot arm, necessitating the use of a counterweight system ...
Allison W Ted - - 2010
Cone photoreceptors in fish are typically arranged into a precise, reiterated pattern known as a "cone mosaic." Cone mosaic patterns can vary in different fish species and in response to changes in habitat, yet their function and the mechanisms of their development remain speculative. Zebrafish (Danio rerio) have four cone ...
Sato Masaki - - 2011
The electroretinogram (ERG) is a non-invasive indicator of retinal function. Light flashes evoke a cornea-negative a-wave followed by a cornea-positive b-wave. Light-adaptation is known to increase the amplitude of cone-dependent b-waves. To identify the underlying mechanism, we recorded rat cone photoresponses in situ, using intravitreally-injected glutamate to block synaptic transmission ...
Mehdi Madah Khawn-i-Muhammad - - 2010
Cone photoreceptor death is a leading cause of blindness in industrialised countries. Despite this, there are few mammalian models available to study cone pathophysiology. The diurnal rodent Arvicanthis possesses a high cone percentage and ease of maintenance. We recently described the effect of ambient light conditions on cyclic disc shedding, ...
Challa N K - - 2010
We recorded L- and M-cone isolating ERGs from human subjects using a silent substitution technique at temporal rates of 12 and 30 Hz. These frequencies isolate the activity of cone-opponent and non-opponent post-receptoral mechanisms, respectively. ERGs were obtained using a sequence of stimuli with different spatial configurations comprising; (1) circular ...
Medina José M - - 2010
We examined different contrast metrics to scale visual latencies for suprathreshold stimuli modulated along tritan confusion lines. S-cone increments ('blue') and decrements ('yellow') were isolated along two different tritan confusion lines, each one having a different luminance value. Reaction times (RT) were evaluated as a function of the Weber contrast ...
Joselevitch Christina - - 2010
Many animal species make use of ultraviolet (UV) light in a number of behaviors, such as feeding and mating. The goldfish (Carassius auratus) is among those with a UV photoreceptor and pronounced UV sensitivity. Little is known, however, about the retinal processing of this input. We addressed this issue by ...
Yetemian Rosanne M - - 2010
The effects of aging and light exposure on cone photoreceptor survival were compared between mouse retinas of neural retina leucine zipper knockout (Nrl(-/-)) mice and double-knockout mice lacking G-protein-coupled receptor kinase 1 (Nrl(-/-)Grk1(-/-)). Mice were reared in total darkness, ambient cyclic light, or constant light, and their retinas were evaluated ...
Anderson Leslie G - - 2010
The UVS cone mechanism is known to light adapt at low intensities in comparison to other cones. We were interested in whether this property was related to higher sensitivity in UVS cones or to network adjustments in sensitivity. We investigated spectral sensitivity of 107 individual cone photoreceptors in rainbow trout ...
Derijck Alwin A H A - - 2010
To establish axonal connections growth cones must navigate multiple intermediate targets before reaching their final target. During this journey growth cones are guided by extracellular repulsive and attractive signals. Although initially identified as repulsive molecules, members of the semaphorin family include both attractants and repellents. How a navigating growth cone ...
Michalakis Stylianos - - 2010
Congenital absence of cone photoreceptor function is associated with strongly impaired daylight vision and loss of color discrimination in human achromatopsia. Here, we introduce viral gene replacement therapy as a potential treatment for this disease in the CNGA3(-/-) mouse model. We show that such therapy can restore cone-specific visual processing ...
Connaughton Victoria P - - 2010
Zebrafish are tetrachromats with red (R, 570 nm), green (G, 480 nm), blue (B, 415 nm), and UV (U, 362 nm) cones. Although neurons in other cyprinid retinas are rich in color processing neural circuitry, spectral responses of individual neurons in zebrafish retina, a genetic model for vertebrate color vision, ...
Busskamp Volker - - 2010
Retinitis pigmentosa refers to a diverse group of hereditary diseases that lead to incurable blindness, affecting two million people worldwide. As a common pathology, rod photoreceptors die early, whereas light-insensitive, morphologically altered cone photoreceptors persist longer. It is unknown if these cones are accessible for therapeutic intervention. Here, we show ...
Dollet Anna - - 2010
In mammals, non-visual responses to light involve intrinsically photosensitive melanopsin-expressing retinal ganglion cells (ipRGCs) that receive synaptic inputs from rod and cone photoreceptors. Several studies have shown that cones also play a role in light entrainment, photic responses of the suprachiasmatic nucleus (SCN), pupil constriction, and sleep induction. These studies ...
Zhang Xian - - 2010
A paradigm is introduced that allows for simultaneous recording of the pattern-onset multifocal visual evoked potentials (mfVEP) to both short-wavelength (SW) and achromatic (A) stimuli. There were 5 sets of stimulus conditions, each of which is defined by two semi-concurrently presented stimuli, A64/SW (a 64% contrast achromatic stimulus and a ...
Garry Deirdre - - 2010
To evaluate cone and cone-driven retinal function in patients with Smith-Lemli-Opitz syndrome (SLOS), a condition characterized by low cholesterol. Rod and rod-driven function in patients with SLOS are known to be abnormal. Electroretinographic (ERG) responses to full-field stimuli presented on a steady, rod suppressing background were recorded in 13 patients ...
Lisney T J - - 2010
The cichlid fish radiations of the African Great Lakes are an important model for evolutionary biology. Cichlids have diverse colour vision systems and predominately express three cone visual pigments. However, rare populations of spectrally distinct cones have been found in a number of species, but it is not known whether ...
Palacios Adri?n G - - 2010
We studied the retinal photoreceptors in the mouse opossum Thylamys elegans, a nocturnal South American marsupial. A variety of photoreceptor properties and color vision capabilities have been documented in Australian marsupials, and we were interested to establish what similarities and differences this American marsupial showed. Thylamys opsin gene sequencing revealed ...
Ribeiro Maria J - - 2010
In the early stages of vision, information is transmitted through distinct physiologically defined pathways. These may be related with three post-receptoral detection mechanisms defined psychophysically in humans. Accordingly, the parvocellular pathway is very sensitive to L-M-cone contrast, processes mainly foveal information and underlies fine discrimination of visual features. The magnocellular ...
Tsujimura Sei-ichi - - 2010
The recent discovery of melanopsin-containing retinal ganglion cells (mRGCs) has led to a fundamental reassessment of non-image forming processing, such as circadian photoentrainment and the pupillary light reflex. In the conventional view of retinal physiology, rods and cones were assumed to be the only photoreceptors in the eye and were, ...
Vincent Ajoy - - 2010
The purpose of the study is (1) to demonstrate the anatomical variation of cone photoreceptor density across normal retina as a sectoral amplitude asymmetry of photopic multifocal electroretinogram (mfERG) and (2) to study the potential presence of sequential or differential, functional cone photoreceptor damage in glaucoma using this amplitude asymmetry. ...
Pang J - - 2010
To test whether fast-acting, self-complimentary (sc), adeno-associated virus-mediated RPE65 expression prevents cone degeneration and/or restores cone function, we studied two mouse lines: the Rpe65-deficient rd12 mouse and the Rpe65-deficient, rhodopsin null ('that is, cone function-only') Rpe65(-/-)::Rho(-/-) mouse. scAAV5 expressing RPE65 was injected subretinally into one eye of rd12 and Rpe65(-/-)::Rho(-/-) ...
Matthews Hugh R - - 2010
The time scale of the photoresponse in photoreceptor cells is set by the slowest of the steps that quench the light-induced activity of the phototransduction cascade. In vertebrate photoreceptor cells, this rate-limiting reaction is thought to be either shutoff of catalytic activity in the photopigment or shutoff of the pigment's ...
Jacobs Gerald H - - 2010
Only two of the four cone opsin gene families found in vertebrates are represented in contemporary eutherian and marsupial species. Recent genetic studies of two species of South American marsupial detected the presence of representatives from two of the classes of cone opsin genes and the structures of these genes ...
H?llstr?m Waldemar - - 2010
We used epitaxially grown monodisperse nanowire arrays to measure cellular forces with a spatial resolution of 1 mum. Nerve cells were cultured on the array and cellular forces were calculated from the displacement of the nanowire tips. The measurements were done in situ on live cells using confocal microscopy. Forces ...
Ng Lily - - 2010
Maturation of the mammalian nervous system requires adequate provision of thyroid hormone and mechanisms that enhance tissue responses to the hormone. Here, we report that the development of cones, the photoreceptors for daylight and color vision, requires protection from thyroid hormone by type 3 deiodinase, a thyroid hormone-inactivating enzyme. Type ...
Sorbara Luigina - - 2010
PURPOSE: The purpose of this report is to demonstrate the use the video-keratoscope in determining the type and size of the cone in keratoconus and PMD patients and the final back optic zone diameter (BOZD) and total lens diameter (LD). METHODS: A retrospective review of one hundred clinical records including ...
Raine J C - - 2010
Rainbow trout possess ultraviolet-sensitive (UVS) cones in their retina that degenerate naturally during development. This phenomenon can be induced with exogenous thyroxine [T4, a thyroid hormone (TH)] treatment. However, the previous T4 exposure experiments employed static water immersion; a method that could introduce confounding stress effects on the fish. Because ...
Garrigan Patrick - - 2010
Cones with peak sensitivity to light at long (L), medium (M) and short (S) wavelengths are unequal in number on the human retina: S cones are rare (<10%) while increasing in fraction from center to periphery, and the L/M cone proportions are highly variable between individuals. What optical properties of ...
Tamada Atsushi - - 2010
The direction of neurite elongation is controlled by various environmental cues. However, it has been reported that even in the absence of any extrinsic directional signals, neurites turn clockwise on two-dimensional substrates. In this study, we have discovered autonomous rotational motility of the growth cone, which provides a cellular basis ...
Packer Orin S - - 2010
The neural coding of human color vision begins in the retina. The outputs of long (L)-, middle (M)-, and short (S)-wavelength-sensitive cone photoreceptors combine antagonistically to produce "red-green" and "blue-yellow" spectrally opponent signals (Hering, 1878; Hurvich and Jameson, 1957). Spectral opponency is well established in primate retinal ganglion cells (Reid ...
Kimura Eiji - - 2010
We show that irradiance-coding alone cannot explain the sustained pupillary constrictions evoked by chromatic and luminance variations in a stimulus. For example, stimulus modulations that decremented the contrasts in L- and M-cones as well as rods and melanopsin photoreceptors produced sustained constrictions rather than the predicted dilations. Although the sustained ...
Lewis Alaron - - 2010
In many retinal diseases, the malfunction that results in photoreceptor loss occurs only in either rods or cones, but degeneration can progress from the affected cell type to its healthy neighbors. Specifically, in human and mouse models of Retinitis Pigmentosa the loss of rods results in the death of neighboring ...
Kono Masahiro - - 2010
Visual pigment proteins belong to the superfamily of G protein-coupled receptors and are the light-sensitive molecules in rod and cone photoreceptor cells. The protein moiety is known as opsin and the ligand in the dark is 11-cis retinal, which serves as both the photon detector and an inverse agonist. While ...
Parker Ryan O - - 2010
11-cis Retinal is the light-sensitive component in rod and cone photoreceptors, and its isomerization to all-trans retinal in the presence of light initiates the visual response. For photoreceptors to function normally, all-trans retinal must be converted back into 11-cis retinal through the visual cycle. While rods are primarily responsible for ...
Fischer M Dominik - - 2010
Purpose: We performed a comprehensive in vivo assessment of retinal morphology and function in cpfl1 (cone photoreceptor function loss 1) mice to better define the disease process in this model of cone dystrophies. Methods: Mice were examined using electroretinography (ERG), confocal scanning laser ophthalmoscopy (cSLO), and spectral domain optical coherence ...
Sivacioglu A - - 2010
Cone and seed characteristics of Anatolian black pine were investigated in a clonal seed orchard for two years, 2002 and 2006. The orchard, originated from Kastamonu-Karadere seed stand was established in 1993 by using 1 year-old grafts in an area of 13 ha, at Hanönü-Günlüburun, northern Turkey and includes 30 ...
Kram Yoseph A - - 2010
The avian retina possesses one of the most sophisticated cone photoreceptor systems among vertebrates. Birds have five types of cones including four single cones, which support tetrachromatic color vision and a double cone, which is thought to mediate achromatic motion perception. Despite this richness, very little is known about the ...
Sabbah Shai - - 2010
Color vision plays a critical role in visual behavior. An animal's capacity for color vision rests on the presence of differentially sensitive cone photoreceptors. Spectral sensitivity is a measure of the visual responsiveness of these cones at different light wavelengths. Four classes of cone pigments have been identified in vertebrates, ...
Ueki Y - - 2010
Mechanical forces acting on focal adhesions (FAs) are believed to be an important determinant for cytoskeletal reorganization. However, the effect of the temporal pattern of forces on cellular responses has not been elucidated. In the present study, we examined the responses of FAs to locally-applied cyclic forces. Magnetic micro beads ...
Brown Bruce M - - 2010
PURPOSE: To evaluate morphologic and functional contributions of Arrestin 1 (Arr1) and Arrestin 4 (Arr4) in cone photoreceptors, the authors examined the phenotypes of visual arrestin knockout mice (Arr1(-/-), Arr4(-/-), Arr1(-/-)Arr4(-/-) [Arr-DKO]) reared in darkness. METHODS: Retinal rods and cones were evaluated in wild-type (WT), Arr1(-/-), Arr4(-/-), and Arr-DKO mice ...
Rha Jungtae - - 2009
It has been shown that after a visible stimulus, optical oscillations of nearly all cone photoreceptors can be observed using long coherence length light and in a few cones using short coherence length light. Here, we show that after exposure to a visible stimulus, a short coherence length imaging source ...
Knott Ben - - 2010
Avian vision is highly developed, with bird retinas containing rod and double-cone photoreceptors, plus four classes of single cones subserving tetrachromatic colour vision. Cones contain an oil droplet, rich in carotenoid pigments (except VS/ultraviolet-sensitive cones), that acts as a filter, substantially modifying light detected by the photoreceptor. Using dietary manipulations, ...
Wang Jin-Shan - - 2009
One of the fundamental mysteries of the human visual system is the continuous function of cone photoreceptors in bright daylight. As visual pigment is destroyed, or bleached, by light, cones require its rapid regeneration, which in turn involves rapid recycling of the pigment's chromophore. The canonical visual cycle for rod ...
Allpress Jesse A - - 2010
Excessive speed is currently one of the primary contributory factors in traffic accidents within roadwork sites around the world. The present study evaluated two novel interventions designed to control traffic speed within an open road, roadwork site in New Zealand where drivers were required to decrease their speed from 100 ...
Lee June-sub - - 2009
Electroretinography (ERG) is a reliable diagnostic tool for the diagnosis of retinal disease. It measures electric potentials occurring in the retina in response to light stimulation. In this study, we examined the normal electroretinogram using the Handheld Multispecies ERG (HMsERG) in Shih Tzu dogs. ERG recordings were performed in twelve ...
Feller K D - - 2009
We report the expression of three visual opsins in the retina of the little brown bat (Myotis lucifugus, Vespertilionidae). Gene sequences for a rod-specific opsin and two cone-specific opsins were cloned from cDNA derived from bat eyes. Comparative sequence analyses indicate that the two cone opsins correspond to an ultraviolet ...
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