Purpose : A great deal of evidence has confirmed that electromagnetic fields can affect the central nervous system and are effective in gene expression as well as development, differentiation, cell proliferation, and apoptosis of embryonic neural cells. This study was conducted to investigate the cellular and molecular changes of cultured human retinal pigment epithelial (hRPE) cells when treated with pulsed electromagnetic fields. Methods : Cultured neonatal hRPE cells with confluency of 60% were exposed to pulsed electromagnetic field of 1 mT intensity and 50 Hz frequency 8 hours daily for 3 days. In addition to cell proliferation and cell death assays, immunocytochemistry for RPE65, Pax6, Nestin and cytokeratin 8/18 proteins were performed. Extracted RNAs were subjected to real-time PCR for Nestin, Pax6, RPE65, and α-SMA. Results : Treated hRPE cells did not demonstrate significant change in terms of cell proliferation and cell death. Protein expressions of Pax6, Nestin, and cytokeratin 8/18 ...

TY - JOUR. T1 - The effects of zinc supplementation on primary human retinal pigment epithelium. AU - Pao, Po-Jung. AU - Emri, Eszter. AU - Abdirahman, Safiya Bishar. AU - Soorma, Talha. AU - Zeng, Hui-Hui. AU - Hauck, Stefanie M. AU - Thompson, Richard B. AU - Lengyel, Imre. N1 - Copyright © 2018 Elsevier GmbH. All rights reserved.. PY - 2018/3/1. Y1 - 2018/3/1. N2 - Population-based and interventional studies have shown that elevated zinc levels can reduce the progression to advanced age-related macular degeneration. The objective of this study was to assess whether elevated extracellular zinc has a direct effect on retinal pigment epithelial cells (RPE), by examining the phenotype and molecular characteristics of increased extracellular zinc on human primary RPE cells. Monolayers of human foetal primary RPE cells were grown on culture inserts and maintained in medium supplemented with increasing total concentrations of zinc (0, 75, 100, 125 and 150 μM) for up to 4 weeks. Changes in cell ...

7-MX has an effect on eye development and myopia [4]. The present study showed that 7-MX barely suppresses the growth of human RPE cells cultured in vitro, but 7-MX could statistically significantly inhibit the expression of ADORA1, ADORA2A, and ADORA2B in RPE cells in short-term treatment. RPE plays a critical role in relaying retinal growth signals to the choroids and sclera [23]. One of the most important mechanisms of myopia formation is that the visual signal concerned with myopia transfers from the neural retinal to the RPE, where fluid exchange transits molecular signals from the retinal and choroid layers to the sclera, followed by scleral remodeling [8]. As confluent monolayers of adult human RPE cultures exhibit characteristics of native RPE [24], it would have been more relevant for our study. 7-MX is a metabolite of caffeine and theobromine shown to work against myopia [4,8,9]. The peak serum concentration after an oral dose of 400 mg 7-MX in adults is around 20 μmol/l with a ...

Abstract: : Purpose: To examine whether cultured RPE cells can be coaxed to differentiate towards retinal ganglion cells using chick ath5 (cath5), either alone or in combination with bFGF. Vertebrate ath5 is a homologue of the Drosophila proneural gene «atonal» and plays an important role in the production of retinal ganglion cells. Previously, we reported that bFGF induced RPE cells to express RA4 immunoreactivity. But bFGF alone did not induce the expression of additional markers or the development of a neural morphology typical of retinal ganglion cells. Methods: RPE was isolated from day 6 chick embryos, and cultured as dissociated cells in the presence of 10% fetal calf serum. RPE cell culture was infected with retrovirus RCAS-cath5 to achieve ectopic expression of cath5. RPE transdifferentiation was assayed using chick retinal ganglion cell markers, including monoclonal antibodies RA4, 4H6, 3A10, and MAP2. Results: Rather surprisingly, ectopic expression of cath5 in cultured RPE cells ...

TY - JOUR. T1 - Retinal pigment epithelial cells produce mitogenic factors for retinal microvascular cells in culture. T2 - A preliminary report. AU - Wong, H. C.. AU - Boulton, M. E.. AU - Clark, P.. AU - Bayly, M.. AU - Marshall, J.. PY - 1987/11. Y1 - 1987/11. N2 - Conditioned media from human retinal pigment epithelial cells have been shown to have mitogenic activity for retinal microvascular cells in vitro. The conditioned media stimulated the proliferation of both bovine retinal capillary endothelial cells and pericytes.. AB - Conditioned media from human retinal pigment epithelial cells have been shown to have mitogenic activity for retinal microvascular cells in vitro. The conditioned media stimulated the proliferation of both bovine retinal capillary endothelial cells and pericytes.. UR - http://www.scopus.com/inward/record.url?scp=0343457139&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=0343457139&partnerID=8YFLogxK. U2 - 10.1038/eye.1987.121. DO - ...

TY - JOUR. T1 - Expression of heme oxygenase-1 is repressed by interferon-γ and induced by hypoxia in human retinal pigment epithelial cells. AU - Udono-Fujimori, Reiko. AU - Takahashi, Kazuhiro. AU - Takeda, Kazuhisa. AU - Furuyama, Kazumichi. AU - Kaneko, Kiriko. AU - Takahashi, Shigeru. AU - Tamai, Makoto. AU - Shibahara, Shigeki. N1 - Copyright: Copyright 2008 Elsevier B.V., All rights reserved.. PY - 2004/7. Y1 - 2004/7. N2 - The retinal pigment epithelium (RPE) is essential for maintenance of photoreceptors and normally functions under conditions enriched with reactive oxygen species. RPE therefore expresses various defense enzymes against oxidative stress, including heme oxygenase-1 (HO-1). HO-1 catalyzes heme breakdown to release iron, carbon monoxide, and biliverdin, which is reduced to bilirubin, a potent radical scavenger. HO-1 expression is induced by various environmental factors, which has been established as a defense mechanism. To explore the hypothesis that the expression level ...

0053] Non-limiting examples of suitable magenta or red or violet organic pigments include C.I. Pigment Red 1, C.I. Pigment Red 2, C.I. Pigment Red 3, C.I. Pigment Red 4, C.I. Pigment Red 5, C.I. Pigment Red 6, C.I. Pigment Red 7, C.I. Pigment Red 8, C.I. Pigment Red 9, C.I. Pigment Red 10, C.I. Pigment Red 11, C.I. Pigment Red 12, C.I. Pigment Red 14, C.I. Pigment Red 15, C.I. Pigment Red 16, C.I. Pigment Red 17, C.I. Pigment Red 18, C.I. Pigment Red 19, C.I. Pigment Red 21, C.I. Pigment Red 22, C.I. Pigment Red 23, C.I. Pigment Red 30, C.I. Pigment Red 31, C.I. Pigment Red 32, C.I. Pigment Red 37, C.I. Pigment Red 38, C.I. Pigment Red 40, C.I. Pigment Red 41, C.I. Pigment Red 42, C.I. Pigment Red 48(Ca), C.I. Pigment Red 48(Mn), C.I. Pigment Red 57(Ca), C.I. Pigment Red 57:1, C.I. Pigment Red 88, C.I. Pigment Red 112, C.I. Pigment Red 114, C.I. Pigment Red 122, C.I. Pigment Red 123, C.I. Pigment Red 144, C.I. Pigment Red 146, C.I. Pigment Red 149, C.I. Pigment Red 150, C.I. Pigment Red 166, ...

TY - JOUR. T1 - Retinal pigment epithelial cells from dystrophic rats form normal tight junctions in vitro. AU - Chang, Chih Wei. AU - Defoe, Dennis M.. AU - Caldwell, Ruth B. PY - 1997/2/6. Y1 - 1997/2/6. N2 - Purpose. In the genetically defective Royal College of Surgeons (RCS) rat model for retinal degeneration, a breakdown occurs in the retinal pigment epithelial (RPE) cell tight junctions just as the photoreceptors begin to degenerate. These experiments sought to determine the impact of the RPE genetic defect on this alteration in the RPE cell tight junctions. Methods. Retinal pigment epithelial cell cultures prepared from RCS and control rats were treated with hormonally defined medium (HDM), base medium conditioned by RCS or control retinas, or unconditioned base medium. The tight junctions formed by these cultures were assayed functionally by measuring transepithelial electrical resistance and permeability. Junction structure was evaluated by immunolocalization of the tight junction ...

A model demonstrating the place of the GPR143 gene in the pathogenesis of ocular albinism type 1. The latter shows the interactions between GPR143 and the different genes responsible for melanogenesis as well as growth factors such as SERPINF1 and VEGF in melanocytes or the retinal pigment epithelium ...

The epigenetic plasticity of amphibian retinal pigment epithelium (RPE) allows them to regenerate the entire retina, a trait known to be absent in mammals. In this study, we investigated the epigenetic plasticity of adult murine RPE to identify possible mechanisms that prevent mammalian RPE from reg …

Lumega-Z is a Medical Food...you will need a DAC (Doctor Authorization Code) number in order to process your order. If you dont have a DAC number, please call us at (888) 512-5550 so that we may assist you. ...

TY - JOUR. T1 - Synthesis of complement factor H by retinal pigment epithelial cells is down-regulated by oxidized photoreceptor outer segments. AU - Chen, Mei. AU - Forrester, John Vincent. AU - Xu, Heping. PY - 2007/4. Y1 - 2007/4. N2 - Complement activation is thought to be involved in the pathogenesis of age-related macular degeneration (AMD), in part because certain gene polymorphisms in complement factor H (CFH), an important regulator of the alternative complement activation pathway, are high risk factors for AMD. How CFH is regulated locally at the retina/choroid interface and how this contributes to AMD development remain unknown. In the present study, we have confirmed that CFH was detectable by immunohistochemistry in the choroid, and at low levels in the RPE cell and interphotoreceptor matrix, but appeared to be concentrated in dense patches in Bruchs membrane. In vitro, cultured human and mouse RPE cells expressed high levels of CFH as evidenced by immunohistochemistry and western ...

The retinoid visual cycle is a sequence of metabolic and transport reactions of retinoids in the retina and the retinal pigment epithelium (RPE). Many proteins are involved in this cycle and play critical roles in the generation of II-cis retinal, the chromophore that binds opsin to form the visual pigments. Mutations of these proteins cause eye diseases that can eventually lead to blindness. RPE65 and LRA T are essential proteins involved in the visual dark cycle to regenerate visual pigments, while RDHIO is thought to produce all-trans retinal, the substrate for the retinal G protein-coupled receptor (RGR) in the photic cycle to regenerate visual pigments. This research is focused on studying the visual cycle proteins (RPE65, LRAT and RDHIO) and tested the hypothesis that the HEK293 cells can be used as an in vitro model to study visual vitamin A metabolism. The protein RPE65 was purified from native bovine RPE and the molecular mass of this protein was determined. Retinoic acid (RA) was found ...

The blood-retinal barrier, or the BRB, is part of the blood-ocular barrier that consists of cells that are joined tightly together to prevent certain substances from entering the tissue of the retina. It consists of non-fenestrated capillaries of the retinal circulation and tight-junctions between retinal epithelial cells preventing passage of large molecules from choriocapillaris into the retina. The blood retinal barrier has two components: the retinal vascular endothelium and the retinal pigment epithelium. Retinal blood vessels that are similar to cerebral blood vessels maintain the inner blood-ocular barrier. This physiological barrier comprises a single layer of non-fenestrated endothelial cells, which have tight junctions. These junctions are impervious to tracer, so many substances can affect the metabolism of the eyeball. The retinal pigment epithelium maintains the outer blood-retinal barrier. Diabetic retinopathy, eye damage that frequently occurs as a result of diabetes, is related ...

congenital hypertrophy of the retinal pigment epithelium answers are found in the Tabers Medical Dictionary powered by Unbound Medicine. Available for iPhone, iPad, Android, and Web.

three experiments with three different cell cultures (*P,0.05). Co, control. doi:10.1371/journal.pone.0048501.gEffects of Smoke in RPEan accelerated ageing process in AMD [24,46,47,48]. We have previously shown that sublethal concentrations of hydrogen peroxide induced senescence-associated ?Galactosidase (SA- al) activity in primary cultured RPE cells [29]. In the experiments of the current study, treatment of primary human RPE cultures with CSE could significantly increase the proportion of SA-?Gal positive cells. Positive staining of SA-?Gal has also been detected in vitro in late passage RPE cultures [49,50] and in vivo in the RPE cells of old primate eyes [51]. In human RPE cells, an increased expression of SA-?Gal staining could be triggered by mild hyperoxia-mediated ROS release [52]. Furthermore, cellular s.And can induce RPE cell death [42]. In our experiments, treatment of primary human RPE cells with 2, 4, and 8 of cigarette smoke extract (CSE) had no significant effects onFigure 5. ...

PURPOSE: To provide long-term (| or =5 years) follow-up data on patients who had previously undergone macular retinal pigment epithelium (RPE) translocation surgery for choroidal new vessels (CNVs) associated with age-related macular degeneration. DESIGN: Retrospective interventional case series. PARTICIPANTS: Four of 9 patients who originally underwent surgery and whose results were reported after 2 years of follow-up were reviewed again 5 to 6 years after surgery. METHODS: All surviving patients from the original trial were contacted, and those who consented to full ocular examination were called in for review. Examination included best-corrected visual acuity (VA), optical coherence tomography (OCT), fundus autofluorescence, fluorescein angiography (FA), and indocyanine green angiography. MAIN OUTCOME MEASURES: Long-term success of RPE translocation was assessed by VA, imaging, angiography, and maintenance of overlying foveal fixation. Comparisons were made to the original 2-year follow-up data

Elevated inflammatory cytokines contribute to the pathogenesis of various retinal diseases such as diabetic retinopathy, retinal vasculitis and retinitis. However, the underlying mechanism of retinal inflammation remains largely unknown. Recent studies demonstrated that acetylcholinesterase (ACHE) is an inflammatory indicator in central neural system. This study was aimed to dissect the role of ACHE in retinal inflammation, and its mechanism of action. Retinal inflammation was induced by intravitreal injection of tumor necrosis factor-α (TNF-α) in heterozygous ACHE knockout mice (ACHE+/-) and wild type mice (ACHE+/+). Donepezil, a well-known ACHE inhibitor, was administrated by daily gavage. Expression of ACHE and intercellular adherent molecule-1 (ICAM-1), infiltration of CD11b+ inflammatory cells, retinal leukostasis and vascular leakage was determined in both ACHE ± and ACHE+/+ mice. ARPE-19â ¯cells, a human retinal pigment epithelial cell line, were cultured for in vitro assay. ...

TY - JOUR. T1 - IL-10 and antibodies to TGF-β2 and PDGF inhibit RPE-mediated retinal contraction. AU - Carrington, Louise. AU - McLeod, David. AU - Boulton, Mike. PY - 2000/4/15. Y1 - 2000/4/15. N2 - PURPOSE. Retinal pigment epithelial (RPE) cells are believed to play a pivotal role in the formation and contraction of epiretinal membranes in proliferative vitreoretinopathy (PVR). In the present study, an organ culture method was used that mimics the contractile stage of PVR, to investigate the contribution of a variety of growth factors in human RPE cell-mediated contraction of the retina. METHODS. Cultured human RPE cells were seeded onto bovine retinal explants. After attachment, cultures received one of the following exogenous growth factors: platelet-derived growth factor (PDGF)-AB, PDGF-BB, basic fibroblast growth factor (bFGF), transforming growth factor (TGF)-β1, TGF-β2, or interleukin (IL)-10; or a neutralizing antibody to PDGF and/or TGF-β2. Control explants were either untreated or ...

The cultured cell collection includes the top differentially expressed genes in 131 human primary and stem cells, purchased from different cell supplying companies, grown and analyzed by BioTime.. Total RNA was extracted from cells, using Qiagen RNeasy mini kits, according to the manufacturers instructions. RNA concentrations were determined using a Beckman DU530 or Nanodrop spectrophotometer and RNA quality was determined by denaturing agarose gel electrophoresis or using an Agilent 2100 bioanalyzer.. Whole-genome expression analysis was carried out using Illumina Human HT-12 v4 BeadArrays (GPL10558). Total RNA was linearly amplified and biotin-labeled, using Illumina TotalPrep kits (Life Technologies, Temecula, CA, USA). The amplified, labeled RNA was quality-controlled using an Agilent 2100 Bioanalyzer. The RNA was then hybridized to Illumina BeadChips, processed, and read using a BeadStation array reader, according to the manufacturers instructions (Illumina, San Diego, CA, USA).. The ...

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Efficient delivery of NF-κB siRNA to human retinal pigment epithelial cells with hyperbranched cationic polysaccharide derivative-based nanoparticles Zhenzhen Liu,1,* Haijun Gong,2,* Rui Zeng,2 Xuan Liang,1 Li-Ming Zhang,1 Liqun Yang,1,* Yuqing Lan2,* 1Institute of Polymer Science, School of Chemistry and Chemical Engineering, Key Laboratory of Designed Synthesis and Application of Polymer Material, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Sun Yat-sen University, Guangzhou, People’s Republic of China; 2Department of Ophthalmology, Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China *These authors contributed equally to this work Abstract: A hyperbranched cationic polysaccharide derivative-mediated small interfering (si)RNA interference strategy was proposed to inhibit nuclear transcription factor-kappa B (NF-

El objetivo de este protocolo es demostrar que el cultivo del pigmento retiniano epitelial (RPE) células en membrana de Bruch humano...

Purpose:In the retina, the balance between pro- and anti-angiogenic factors is critical for angiogenesis control but is also involved in cell survival and maintenance. For instance, the anti-angiogenic factor PEDF is neuroprotective for photoreceptors (PRs) in models of retinal degeneration. We previously reported upregulation of VEGF (24h to 48h post lesion) in the light-damage (LD) model. Furthermore, systemic delivery of PEDF, as well as lentiviral gene transfer of an anti-VEGF antibody rescue PRs from cell death. Studies in vitro show that VEGF induces retinal endothelial cells apoptosis via the alteration of the Akt1/p38 MAPK signalling pathway under hypoxic conditions. Thus, in this study, we investigate the effect of high levels of VEGF on retinal pigmented epithelium (RPE) permeability and molecular targets expression after light-induced PR degeneration. Methods:To characterize the action of VEGF in the retina during the course of LD, we exposed adult Balb/c mice to 5000 lux f

Figure 2. Comparison of the pathology of normal and rdd chicken retinas at 3-4 months. Comparison of normal (A) and rdd (B) retina at 3-4 months of age, both to scale. The rdd retina shows marked atrophy of all layers with virtually complete loss of photoreceptors and replacement by gliosis. GCL = ganglion cell layer, IPL = inner plexiform layer, INL = inner nuclear layer, PRL = photoreceptor layer and RPE = retinal pigment epithelium. Both haematoxylin and eosin at 340x magnification. (C) High power view of the rdd retina showing marked atrophy. Note in particular the complete absence of the outer nuclear layer (usually seen between the inner nuclear and photoreceptor layers). The photoreceptor layer shows loss of photoreceptors, gliosis and prominent clefts above the remnant of the retinal pigment epithelium. GCL = ganglion cell layer, IPL = inner plexiform layer, INL = inner nuclear layer, PRL = photoreceptor layer, RPE = retinal pigment epithelium. Haematoxylin and eosin at 1,800x ...

Choroideremia occurs almost exclusively in males. In childhood, night blindness is the most common first symptom. As the disease progresses there is loss of peripheral vision leading to tunnel vision, and later a loss of central vision. Progression of the disease continues throughout the individuals life, although both the rate and the degree of vision loss vary among those affected, even within the same family.. Vision loss due to choroideremia is caused by degeneration of several layers of cells that are essential to sight. These layers, which line the inside of the back of eyes, are called the choroid, the retinal pigment epithelium and the photoreceptors. The choroid consists of several blood vessel layers that are located between the retina and the sclera (the white of the eye). Choroidal vessels provide the retinal pigment epithelium and photoreceptors with oxygen and nutrients necessary for normal function. The retinal pigment epithelium and the photoreceptors are part of the retina. ...

Advances in the discovery of the causes of monogenic retinal disorders, combined with technologies for the delivery of DNA to the retina, offer enormous opportunities for the treatment of previously untreatable blinding diseases. However, for gene augmentation to be most effective, vectors that have the correct cell-type specificity are needed. While animal models are very useful, they often exhibit differences in retinal cell surface receptors compared to human retina. In this study, we evaluated the use of an ex vivo organotypic explant system to test the transduction efficiency and tropism of 7 different adeno-associated viral type 2 (AAV2) serotypes in human retina and retinal pigment epithelium-choroid: AAV2/1, AAV2/2, AAV2/4, AAV2/5, AAV2/6, AAV2/8, and AAV2/9, all driving expression of GFP under control of the cytomegalovirus promoter. After 7 days in culture, we found that AAV2/4 and AAV2/5 are particularly efficient at transducing photoreceptor cells and that AAV2/5 is highly specific ...

Advances in the discovery of the causes of monogenic retinal disorders, combined with technologies for the delivery of DNA to the retina, offer enormous opportunities for the treatment of previously untreatable blinding diseases. However, for gene augmentation to be most effective, vectors that have the correct cell-type specificity are needed. While animal models are very useful, they often exhibit differences in retinal cell surface receptors compared to human retina. In this study, we evaluated the use of an ex vivo organotypic explant system to test the transduction efficiency and tropism of 7 different adeno-associated viral type 2 (AAV2) serotypes in human retina and retinal pigment epithelium-choroid: AAV2/1, AAV2/2, AAV2/4, AAV2/5, AAV2/6, AAV2/8, and AAV2/9, all driving expression of GFP under control of the cytomegalovirus promoter ...

0039]More specifically, examples of the organic pigment include perylene-compound pigments, such as C.I. Pigment Red 179, C.I. Pigment Red 190, C.I. Pigment Red 224, C.I. Pigment Violet 29, or the like; perynone-compound pigments, such as C.I. Pigment Orange 43, C.I. Pigment Red 194 or the like; quinacridone-compound pigments, such as C.I. Pigment Violet 19, C.I. Pigment Violet 42, C.I. Pigment Red 122, C.I. Pigment Red 192, C.I. Pigment Red 202, C.I. Pigment Red 207, C.I. Pigment Red 209 or the like; quinacridonequinone-compound pigments, such as C.I. Pigment Red 206, C.I. Pigment Orange 48, C.I. Pigment Orange 49, or the like; anthraquinone-compound pigments, such as C.I. Pigment Yellow 147 or the like; anthanthrone-compound pigments, such as C.I. Pigment Red 168 or the like; benzimidazolone-compound pigments, such as C.I. Pigment Brown 25, C.I. Pigment Violet 32, C.I. Pigment Yellow 180, C.I. Pigment Yellow 181, C.I. Pigment Orange 36, C.I. Pigment Orange 62, C.I. Pigment Red 185, or the ...

Non-invasive reflectance imaging of the human RPE cell mosaic is demonstrated using a modified confocal adaptive optics scanning light ophthalmoscope (AOSLO). The confocal circular aperture in front of the imaging detector was replaced with a combination of a circular aperture 4 to 16 Airy disks in diameter and an opaque filament, 1 or 3 Airy disks thick. This arrangement reveals the RPE cell mosaic by dramatically attenuating the light backscattered by the photoreceptors. The RPE cell mosaic was visualized in all 7 recruited subjects at multiple retinal locations with varying degrees of contrast and cross-talk from the photoreceptors. Various experimental settings were explored for improving the visualization of the RPE cell boundaries including: pinhole diameter, filament thickness, illumination and imaging pupil apodization, unmatched imaging and illumination focus, wavelength and polarization. None of these offered an obvious path for enhancing image contrast. The demonstrated implementation of dark

For proper function of the retina, the correct proportions of retinal cell types must be generated, they must be organized into cell-specific laminae, and appropriate synaptic connections must be made. To understand the genetic regulation of retinal development, we have analyzed mutations in the mosaic eyes gene that disrupt retinal lamination, the localization of retinal cell divisions to the retinal pigmented epithelial surface and retinal pigmented epithelial development. Although retinal organization is severely disrupted in mosaic eyes mutants, surprisingly, retinal cell differentiation occurs. The positions of dividing cells and neurons in the brain appear normal in mosaic eyes mutants, suggesting that wild-type mosaic eyes function is specifically required for normal retinal development. We demonstrate that mosaic eyes function is required within the retinal pigmented epithelium, rather than in dividing retinal cells. This analysis reveals an interaction between the retinal pigmented ...

Although these experiments use cells that heterologously express CaV1.3 and hBest1, it is very likely that our results are physiologically relevant to RPE cell function. Human RPE cells and the RPE cell line ARPE-19 express CaV α1.3 and β2 subunits (Wimmers et al., 2008). Furthermore, it has been shown recently that hBest1 coimmunoprecipitates with CaVβ subunits from freshly isolated human RPE cells (Strauss et al., 2008). These results suggest that it is likely that the interaction between hBest1 and CaV subunits has an important physiological function and may help resolve the present controversy of whether Best1 is a Cl− channel (Hartzell et al., 2008).. As reviewed in the Introduction, there is strong evidence that bestrophins are Cl− channels (Hartzell et al., 2008), but this idea has been questioned (Marmorstein et al., 2004a,b, 2006; Rosenthal et al., 2005; Marmorstein and Kinnick, 2007). These authors have proposed that hBest1 is not a Cl− channel but rather is a regulator of ...

A Vossius ring appears when iris pigment epithelial cells are compressed against the anterior surface of the lens, depositing a ring of melanin pigment concentric with the pupil.. If the lens capsule is disrupted, a cataract may form immediately. The capsule is thinnest at the posterior pole, the point farthest from the lens epithelial cells. The epithelium of the lens may be stimulated by trauma to form an anterior fibrous plaque just inside the capsule. The lens zonular fibers are points of relative weakness; if they rupture, lens displacement occurs, either partial (subluxation) or complete (luxation). Focal areas of zonular rupture may allow formed vitreous to enter the anterior chamber.. Commotio retinae (Berlin edema) often complicates blunt trauma to the eye. Although it is most prominent in the macula, commotio retinae can affect any portion of the retina. The retinal opacification seen clinically results from disruption in the architecture of the photoreceptor outer segments and the ...

TY - JOUR. T1 - Effect of vital dyes on retinal pigmented epithelial cell viability and apoptosis. T2 - Implications for chromovitrectomy. AU - Penha, Fernando M.. AU - Pons, Marianne. AU - De Paula Fiod Costa, Elaine. AU - Rodrigues, Eduardo B.. AU - Maia, Mauricio. AU - Marin-Castanõ, Maria E.. AU - Farah, Michel Eid. N1 - Publisher Copyright: © 2013 S. Karger AG, Basel. Copyright: Copyright 2015 Elsevier B.V., All rights reserved.. PY - 2013/4/18. Y1 - 2013/4/18. N2 - Purpose: To investigate the in vitro effect of vital dyes on toxicity and apoptosis in a human retinal pigment epithelial cell line. Methods: ARPE-19 cells were exposed to brilliant blue (BBG), Evans Blue (EB), bromophenol blue (BroB), indocyanine green (ICG), infracyanine green (IfCG), light green (LG), fast green (FG), indigo carmine (IC) and Congo red (CR). Balanced salt solution was used as the control. Five different concentrations and 2 exposure times were tested. Cell viability was determined by the MTS (1-solution ...

The purpose of this study was to characterize the cell surface proteome of native compared to cultured equine retinal pigment epithelium (RPE) cells. The RPE plays an essential role in visual function and represents the outer blood-retinal barrier. We are investigating immunopathomechanisms of equine recurrent uveitis, an autoimmune inflammatory disease in horses leading to breakdown of the outer blood-retinal barrier and influx of autoreactive T-cells into affected horses vitrei. Cell surface proteins of native and cultured RPE cells from eye-healthy horses were captured by biotinylation, analyzed by high resolution mass spectrometry coupled to liquid chromatography (LC MS/MS), and the most interesting candidates were validated by PCR, immunoblotting and immunocytochemistry. A total of 112 proteins were identified, of which 84% were cell surface membrane proteins. Twenty-three of these proteins were concurrently expressed by both cell states, 28 proteins exclusively by native RPE cells. Among the

|i|Background|/i|. The flow field of aqueous humor correlates to the stiffness of iris pigment epithelium (IPE) which acts as a wall of posterior chamber. We focus on the variations of IPE stiffness in a rat ocular hypertension (OHT) model, so as to prepare for exploring the mechanism of duration of OHT.|i| Methods|/i|. Episcleral venous cauterization (EVC) was applied on one eye of male adult Sprague-Dawley rats to induce chronic high intraocular pressure. According to the duration of OHT (0, 1, 2, 4, and 8 weeks), rats were randomly divided into Gw0, Gw1, Gw2, Gw4, and Gw8. Atomic force microscope (AFM) analysis was applied to test IPE stiffness in three regions: iris root, mid-periphery, and pupillary-margin in each group. Histological changes of IPE were also examined in Gw4 and Gw8.|i| Results|/i|. There was an overall growing tendency of IPE stiffness in EVC eye. IPE in EVC eye was significantly stiffer than fellow eye in Gw2, Gw4, and Gw8 (in iris root, mid-periphery, and pupillary-margin, p<

De Potter, Patrick. Clinical case--photo essay. Primary cyst of the iris pigment epithelium.. In: Bulletin de la Société belge dophtalmologie, , no. 307, p. 63-4 (2008 ...

TY - JOUR. T1 - Loss of NAMPT in aging retinal pigment epithelium reduces NAD+ availability and promotes cellular senescence. AU - Jadeja, Ravirajsinh N.. AU - Powell, Folami L.. AU - Jones, Malita A.. AU - Fuller, Jasmine. AU - Joseph, Ethan. AU - Thounaojam, Menaka C.. AU - Bartoli, Manuela. AU - Martin, Pamela M.. N1 - Publisher Copyright: © 2018, Impact Journals LLC. Copyright: Copyright 2018 Elsevier B.V., All rights reserved.. PY - 2018/6/1. Y1 - 2018/6/1. N2 - Retinal pigment epithelium (RPE) performs numerous functions critical to retinal health and visual function. RPE senescence is a hallmark of aging and degenerative retinal disease development. Here, we evaluated the temporal expression of key nicotinamide adenine dinucleotide (NAD+)-biosynthetic genes and associated levels of NAD+, a principal regulator of energy metabolism and cellular fate, in mouse RPE. NAD+ levels declined with age and correlated directly with decreased nicotinamide phosphoribosyltransferase (NAMPT) expression, ...

Hui, S., Yi, L. and Fengling, Q. L. (2009), Effects of Light Exposure and Use of Intraocular Lens on Retinal Pigment Epithelial Cells In Vitro. Photochemistry and Photobiology, 85: 966-969. doi: 10.1111/j.1751-1097.2008.00506.x ...

Non-invasive reflectance imaging of the human RPE cell mosaic is demonstrated using a modified confocal adaptive optics scanning light ophthalmoscope (AOSLO). The confocal circular aperture in front of the imaging detector was replaced with a combination of a circular aperture 4 to 16 Airy disks in diameter and an opaque filament, 1 or 3 Airy disks thick. This arrangement reveals the RPE cell mosaic by dramatically attenuating the light backscattered by the photoreceptors. The RPE cell mosaic was visualized in all 7 recruited subjects at multiple retinal locations with varying degrees of contrast and cross-talk from the photoreceptors. Various experimental settings were explored for improving the visualization of the RPE cell boundaries including: pinhole diameter, filament thickness, illumination and imaging pupil apodization, unmatched imaging and illumination focus, wavelength and polarization. None of these offered an obvious path for enhancing image contrast. The demonstrated implementation ...

Summary: The purpose of the study is to analyse the effectiveness of pedicled RPE (retinal pigment epithelium) - choroid graft autotranslocation in scarred neovascular age-related macular degeneration (AMD) treatment. Material and Methods. Pedicled RPE - choroid graft autotranslocation was performed on 8 patients with scarred wet AMD. Follow-up was from 6 to 30 months. Visual acuity, ophthalmoscopy, optical coherent tomography and indocian-green angiography were analysed. Results. The average visual acuity increased from 0.009±0.006 to 0.018±0.022 (p=0.15). Visual acuity increased in 50% of the patients. In 50% of patients visual acuity decreased, which was associated with proliferative vitreoretinopathy in post-op period with retinal detachment formation. No cases of choroidal neovascularization recurrence were detected. According to angiography data normal choroidal perfusion in the rotated RPE - choroid patch was revealed after 1 month during the follow-up examination. Conclusion. Pedicled ...

One of the most challenging efforts in drug delivery is the targeting of the eye. The eye structure and barriers render this organ poorly permeable to drugs. Quite recently the entrance of nanoscience in ocular drug delivery has improved the penetration and half-life of drugs, especially in the anterior eye chamber, while targeting the posterior chamber is still an open issue. The retina and the retinal pigment epithelium/choroid tissues, located in the posterior eye chamber, are responsible for the majority of blindness both in childhood and adulthood. In the present study, we used magnetic nanoparticles (MNPs) as a nanotool for ocular drug delivery that is capable of specific localization in the retinal pigmented epithelium (RPE) layer. We demonstrate that, following intraocular injection in Xenopus embryos, MNPs localize specifically in RPE where they are retained for several days. The specificity of the localization did not depend on particle size and surface properties of the MNPs used in this work

This study investigates the temporal and spatial interchange of the aromatic amino acid phenylalanine (Phe) between human retinal pigment epithelial cell line (ARPE-19) and tachyzoites of the apicomplexan protozoan parasite Toxoplasma gondii (T. gondii). Stable isotope labelling by amino acids in cell culture (SILAC) is combined with Raman micro-spectroscopy to selectively monitor the incorporation of deuterium-labelled Phe into proteins in individual live tachyzoites. Our results show a very rapid uptake of L-Phe(D8) by the intracellular growing parasite. T. gondii tachyzoites are capable of extracting L-Phe(D8) from host cells as soon as it invades the cell. L-Phe(D8) from the host cell completely replaces the L-Phe within T. gondii tachyzoites 7â€9 hours after infection. A quantitative model based on Raman spectra allowed an estimation of the exchange rate of Phe as 0.5â€1.6 Ã- 104 molecules/s. On the other hand, extracellular tachyzoites were not able to consume ...

Here, we report that genome editing by CRISPR-Cas9 induces a p53-mediated DNA damage response and cell cycle arrest in immortalized human retinal pigment epithelial cells, leading to a selection against cells with a functional p53 pathway. Inhibition of p53 prevents the damage response and increases the rate of homologous recombination from a donor template. These results suggest that p53 inhibition may improve the efficiency of genome editing of untransformed cells and that p53 function should be monitored when developing cell-based therapies utilizing CRISPR-Cas9. CRISPR-Cas9-induced DNA damage triggers p53 to limit the efficiency of gene editing in immortalized human retinal pigment epithelial cells.

Cerium dioxide (CeO2) engineered nanoparticles (NP) are used as fuel-borne catalysts in off-road diesel engines, which can lead to exhaust emissions of respirable CeO2 NP. Other metal oxides may act as photo-catalysts which induce the generation of free radicals upon exposure to UV radiation or visible light. The current study tested the hypothesis that CeO2 NP would cause a dose-dependent phototoxic reaction in human-derived retinal pigment epithelial cells (ARPE-19) after UV exposure. Two samples of CeO2 NP (Alfa Aesar, 36-99 nm; NanoAmor, 6-60 nm) were suspended in cell culture media with 10% fetal bovine serum (FBS) at concentrations: 0, 3, 10, 20, 30, 55, 100ug/ml or 20ug/m1 TiO2 NP (Degussa P25; positive control) and administered to ARPE-19 cells grown in 24-well plates. Plates were either exposed to UV radiation (t=90min) or kept in the dark. After 24hrs, cell viability was determined with a calcein-AM/propidium iodide stain. Exposure to higher concentrations of CeO2 NP reduced cell ...

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Anna Wiktor, PhD graduate of the Jagiellonian University, Faculty of Biochemistry, Biophysics and Biotechnology, Krakow, and she obtained MSc in biotechnology. Master thesis was entitled: The role of photodynamic stress on phagocytosis and pilot study of mRNA expression of heme oxygenase -1 in retinal pigmented epithelium, which she defended in 2006. Just after study she continued research in PhD studies in Faculty of Biochemistry, Biophysics and Biotechnology. During studies she participated in few international trainings, including trainings in Biochemistry Department of Medical College of Wisconsin, Milwaukee, USA and in the Eye Institute of Medical College of Wisconsin. PhD thesis entitled Modulatory effects of melanosomes on expression of heme oxygenase-1 in retinal pigment epithelium cells under oxidative stress in vitro was defended in 2013 and afterwards she was employed in Biophysics Department, Faculty of Biochemistry, Biophysics and Biotechnology, as assistant professor. In ...

Recent studies have implicated local inflammation and activation of complement amongst the processes involved in the pathogenesis of age-related macular degeneration (AMD). Several lines of investigation also indicate that bis-retinoid pigments, such as A2E, that accumulate as lipofuscin in retinal pigment epithelial (RPE) cells, contribute to the disease process. In an investigation of a potential trigger for complement activation in AMD, we explored the notion that the complex mixture of products resulting from photooxidation of A2E might include a range of fragments that could be recognized by the complement system as foreign and that could serve to activate the complement system, leading to low-grade inflammation. To this end, we established an in vitro assay by using human serum as a source of complement, and we measured products of C3 activation by enzyme immunoassay. Accordingly, we found that the C3 split products inactivated C3b (iC3b) and C3a were elevated in serum, overlying ARPE-19 ...

Cultured RPE cells of five human donors were treated with one of four APCs (C18:1-PC, C20:1-PC, C21:1-PC or C22:1-PC) in different concentrations in DMEM/10% FCS. Cell viability was tested by the trypan blue exclusion assay. Attachment was assessed after a 2 h incubation of RPE cells on coated 24-well-plates and subsequent MTT testing. Cellular spreading is characterized by cytoplasmic halo formation and was quantified by counting four separate fields of RPE cells allowed to spread on coated 24-well-plates for 4 h. Migration was assessed by a modification of the Boyden chamber method in microchemotaxis chambers with polycarbonated filters. ...

The retinal pigment epithelium (RPE) contains numerous melanosomes, but analysis of their formation and function in mammalian models has been hampered by the short time window for melanosome biogenesis in this cell layer. In their study on page 1400, Clare Futter and colleagues take advantage of this timing because it facilitates molecular manipulation using morpholinos, and exploit zebrafish as a model system to genetically dissect melanosome biogenesis in the RPE. Morpholino-mediated knockdown of OA1 greatly reduced the number of melanosomes, but did not affect their size. Next, the authors used 3D electron microscopy to identify two populations of melanosome in the RPE that have similar volumes but are readily distinguishable by their cylindrical or spherical shape. Interestingly, they found that only the cylindrical melanosomes entered the apical processes. The authors then examined the effect of morpholino-mediated knockdown of PMEL, a pigmented-cell-specific protein, on melanosome shape. ...

According to a release from the Medical University of South Carolina (MUSC), one approach that researchers have explored to treat retinal diseases such as age-related macular degeneration (AMD) involves transplantation of retinal pigment epithelium cells (RPE) derived from induced pluripotent stem cells (iPSCs)

Purpose Retinal pigment epithelium (RPE) dysfunction underlies the retinal degenerative process in age-related macular degeneration (AMD), and thus RPE cell replacement provides an ideal treatment target. RPE monolayer in pets of all age group organizations, and frequently included internalized photoreceptor external sections. No pathology was noticed. Findings OpRegen RPE cells made it, rescued visible function, maintained pole and cone photoreceptors long lasting in the RCS rat. Therefore, these data support the make use of of OpRegen RPE cells for the treatment of human being RPE cell disorders including AMD. Translational Relevance Our book xeno-free RPE cells reduce issues of pet produced pollutants while offering a encouraging potential therapy to the unhealthy retina. = 242) had been utilized for this research. All pets had been given a regular lab chow and managed on a 12-hour dark/light routine. All pets had been supervised daily for general wellness and ophthalmic condition. Pets had ...

Melanosomes and lipofuscin were isolated from 14-, 59-, and 76-year-old, human retinal pigment epithelium specimens and examined. The morphological features of these samples were studied by scanning electron microscopy and atomic force microscopy, and the photoionization properties were examined by photoelectron emission microscopy. Ovoid- and rod-shaped melanosomes were observed. The size of the granules and the distribution between the two shapes show no significant age-dependent change. However, there is a higher occurrence of irregularly shaped aggregates of small round granules in older samples which suggests degradation or damage to melanosomes occurs with age. The melanosomes from the 14-year-old donor eye are well characterized by a single photoionization threshold, 4.1 eV, while the two older melanosomes exhibit two thresholds around 4.4 and 3.6 eV. Lipofuscin from both young and old cells show two thresholds, 4.4 and 3.4 eV. The similarity of the potentials observed for aged ...

My lab focuses on retinal repair following inherited and age-associated degeneration and modeling disease-in-a-dish using stem cells technologies. I have been involved in this work since 2004 as a graduate student in Dr. Thomas Rehs lab. We have developed in vitro methodologies for generating all the various retinal cell types, including retinal neurons and retinal pigment epithelium cells, from both human and mouse embryonic stem cells and induced pluripotent stem cells. I was one of the first to publish directed retinal differentiation protocols in the US and the use of these cells for regenerative medicine. In October 2011, I established my own lab at the Buck Institute for Research on Aging, Novato, CA. The research is primarily focused on (1) exploring the potential and challenges in retinal repair and (2) using in vivo models and stem-cell based in vitro model systems to understand various retinal degenerations. In 2018, my lab moved to UCSFs Department of Ophthalmology and housed at the ...

Background: Subretinal microphotodiode array (MPDA) is a type of visual prosthesis used for the implantation in the subretinal space of patients with progressive photoreceptor cell loss. The present study aimed to evaluate the effect of materials for MPDA on the viability, apoptosis and barrier function of cultured pig retinal pigment epithelium (RPE) cells.. Methods: Primary culture of pig RPE cells was performed and 24 pig eyes were used to start RPE culture. The third passage of the cultures was plated on different materials for MPDA and MPDAs. The tetrazolium dye-reduction assay (MTT) was used to determine RPE cell viability. Flow cytometry was measured to indicate the apoptosis rates of RPE cells on different materials. RPE cells were also cultured on microporous filters, and the transepithelial resistance and permeability of the experimental molecule were measured to determine the barrier function.. Results: The data from all the methods indicated no significant difference between the ...

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Global Pigment Supplier Directory, Pigment, Pigment Manufacturers, Pigment Factories, Pigment Manufacturing, Pigment Manufacturer, Factory,Pigment Export Company, Pigment Suppliers, Exporters, Pigment Producers, Wholesalers, Distributors, International Pigment, OEM Pigment, Chemical & Plastics.

Expression of both Otx2 and Mitf proteins is rapidly downregulated in Tyrp1-Cretg/0;β-cateninfloxdel/FL RPE; therefore, we asked whether β-catenin associates with their enhancers in vivo. We identified six putative TCF/LEF binding sites (Hallikas et al., 2006) in a 2248bp-fragment of the RPE-specific Mitf-D enhancer, positioned at -1393, -1389, -389, -364, -321 and -132 relative to the transcriptional start site. β-catenin binds at or near these sites, as determined by ChIP using native RPE lysate from E12.5 embryos (Fig. 4I). To examine whether β-catenin can transcriptionally activate Mitf, the Mitf-D enhancer was cloned into the pGL3B luciferase reporter. β-catenin produced an 8-fold increase in luciferase activity, and this activation was reduced by co-transfection with ΔTCF3 or by mutation of all potential TCF/LEF binding sites (Fig. 4I). Furthermore, one putative TCF/LEF binding site was identified in the T0 enhancer of Otx2 (Martinez-Morales et al., 2003), within in a region that is ...

The myo-inositol depletion hypothesis remains a leading but still controversial contender among proposed pathogenetic mechanisms for the chronic complications of diabetes. The multifaceted interrelationships among altered tissue myo-inositol content and metabolism and tissue function have been difficult to elucidate in diabetic animal models due in part to the complex, heterogeneous nature of tissues prone to diabetic complications. The retinal pigment epithelium consists of a homogenous cell monolayer that exhibits related alterations in myo-inositol metabolism and function in diabetic animals. Nontransformed human retinal pigment epithelial (hRPE) cells, which retain their general phenotypic and morphological characteristics during monolayer culture in vitro, were examined for parallel alterations in myo-inositol metabolism and cell function when grown under carefully controlled conditions in medium containing hyperglycemic concentrations of glucose. Exposure of hRPE cells to 20-40 mM ...

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Dysfunction of the retinal pigment epithelium (RPE) is implicated in numerous forms of retinal degeneration. The readily accessible environment of the eye makes it particularly suitable for the transplantation of RPE cells, which can now be derived from autologous induced pluripotent stem cells (iPSCs), to treat retinal degeneration. For RPE transplantation to become feasible in the clinic, patient-specific somatic cells should be reprogrammed to iPSCs without the introduction of reprogramming genes into the genome of the host cell, and then subsequently differentiated into RPE cells that are well characterized for safety and functionality prior to transplantation. We have reprogrammed human dermal fibroblasts to iPSCs using nonintegrating RNA, and differentiated the iPSCs toward an RPE fate (iPSC-RPE), under Good Manufacturing Practice (GMP)-compatible conditions. Using highly sensitive assays for cell polarity, structure, organelle trafficking, and function, we found that iPSC-RPE cells in culture

Best vitelliform macular dystrophy (BMD) is an autosomal dominant inherited macular degenerative disease caused by mutations in the gene BEST1 (formerly VMD2). Prior reports indicate that BMD is characterized histopathologically by accumulation of lipofuscin in the retinal pigment epithelium (RPE). However, this accumulation has not been quantified and the chemical composition of lipofuscin in BMD has not been examined. In this study we characterize the histopathology of a donor eye from a rare individual homozygous for a mutation (W93C) in BEST1. We find that this individuals disease was not any more severe than has been described for heterozygotes. We then used this tissue to quantify lipofuscin accumulation by enriching intracellular granules from RPE cells on sucrose gradients and counting the granules in each density fraction. Granules from the homozygous donor eye as well as a donor eye from an individual heterozygous for the mutation T6R were compared with age-matched control eyes. ...

How does blue light cause damage to the eye?. The retina. Animal studies since 1980 has shown that prolonged exposure of high intensity blue light resulted in inflammation and damage to the retinal pigment epithelium (RPE). The RPE is a very delicate layer of cells which is essential in the maintenance and function of the retinal photoreceptors (also known as rods and cones). Melanin, a common pigment component found in high concentration in the RPE strongly absorbs blue light resulting in oxidative damage to the RPE cells. The human eye has natural protection against exposure to blue light. Both the human lens and lutein, a yellow pigment found in high concentration in the macula (the centre of the retina) filter blue light thereby offering some but inadequate protection to the photoreceptors. This repeated phototoxicity and injury eventually leads to permanent damage to the retina causing age related macular degeneration (AMD). AMD is the commonest cause of irreversible blindness in old age ...

TY - JOUR. T1 - Activation of ERK1/2-mTORC1-NOX4 mediates TGF-β1-induced epithelial-mesenchymal transition and fibrosis in retinal pigment epithelial cells. AU - Kim, Soo Jin. AU - Kim, Yun Sang. AU - Kim, Jeong Hun. AU - Jang, Ha Young. AU - Ly, Dat Da. AU - Das, Ranjan. AU - Park, Kyu Sang. N1 - Funding Information: This work was supported by the Medical Research Center Program (2017R1A5A2015369) from the Ministry of Science and ICT, and the Korea Health Technology R&D Project through the KHIDI (HI18C2196) from the Ministry of Health & Welfare, and Myung Sun Kim Memorial Foundation (2016). Funding Information: This work was supported by the Medical Research Center Program ( 2017R1A5A2015369 ) from the Ministry of Science and ICT , and the Korea Health Technology R&D Project through the KHIDI ( HI18C2196 ) from the Ministry of Health & Welfare , and Myung Sun Kim Memorial Foundation (2016) . Publisher Copyright: © 2020 Elsevier Inc.. PY - 2020/8/27. Y1 - 2020/8/27. N2 - Transforming growth ...

I have a small nit-pick about the in-built documentation at 2.3.5.1 Pigments within the first paragraph. (Its also in the online wiki, in Tutorial Section 3.3, under Advanced Texture Options / Pigments... http://wiki.povray.org/content/Documentation:Tutorial_Section_3.3#Gamma_in_Legacy_Scenes Both places say this: Pigments can also be layered one on top of the next so long as the uppermost layers are at least partially transparent so the ones beneath can show through. As this is mentioned as a general statement in the very first paragraph, and before any qualifications are given, a naive or new-user might naturally assume that the following construct is a nice way to get, for example, a sort of color-filtered bozo effect.(Im using specific pigments to clarify the point)... texture{ pigment{bozo} pigment {rgbt ,.2,.5,.7,.5, ...... But that doesnt work-- the second pigment completely overrides the first, which could be a frustrating surprise-- because adding pigments together this way ...

Patients having eye exams in Houston who are told that they have Bear Tracks, Retina Freckles or Pigment Spots should be aware that there may actually have an increased need for colonoscopy to screen for polyps and colon cancer. You may wonder what having a colonoscopy for colon cancer risk possibly have to do with your eyes? As it turns out-plenty! The retinal pigmented epithelium (RPE) is a layer of the retina which can sometimes be thicker than normal at birth-or hypertrophic. During regular eye exams when we find these areas of retinal pigmented epithelial hypertrophy they typically they do not cause any vision problems or symptoms and are pretty unremarkable, commented Houston eye specialist Dr. Da-Thuy Van an Ophthalmologist at The Eye Clinic of Texas.. Congenital Retinal Pigment Epithelial Hypertrophy (CHRPE) is usually found before patients reach 30 years of age and although they may enlarge with time they usually do not lead to malignancies like colon cancer. However, there is ...

Anytime subretinal fluid accumulates in the space between the neurosensory retina and the underlying retinal pigment epithelium (RPE), a retinal detachment occurs. Depending on the mechanism of subretinal fluid accumulation, retinal detachments traditionally have been classified into rhegmatogenous, tractional, and exudative.

Anytime subretinal fluid accumulates in the space between the neurosensory retina and the underlying retinal pigment epithelium (RPE), a retinal detachment occurs. Depending on the mechanism of subretinal fluid accumulation, retinal detachments traditionally have been classified into rhegmatogenous, tractional, and exudative.

Results Analysis showed ranibizumab permeated the retina via intercellular clefts, whereas aflibercept was taken up by ganglion cells, cells of the inner and outer retinal layers and the retinal pigment epithelium (RPE). Stasis and haemolysis in the choriocapillaris and choroidal vessels were more frequent after aflibercept treatment, which caused hypertrophy and death of individual RPE cells. The area of the CC was significantly reduced after both drugs compared with controls, but the reduction of the CC endothelium thickness, number of fenestrations and the areas with haemolysis were more pronounced after aflibercept.. ...

Effect of organic pigments on coating properties. 1. The size of organic pigment particles has a great influence on the color performance of the coating. On the one hand, it will affect the hiding power and tinting strength of the coating. In the range of pigment, the particle size will increase, and the hiding power of the coating will increase. When the pigment particles become smaller, the coating will increase in specific surface area. The tinting strength is increased and the pigment particle size also has an effect on the color shade of the coating. Generally, the particle size distribution is larger, the color is darker, and the color is brighter. The other is that the strength of the pigment also affects the UV resistance of the coating. When the particle becomes smaller, the specific surface area increases, the absorbed light energy increases, and is damaged. The degree is also increased, so the paint fades faster. The small amount of pigment is less gravity, and the coating is not easy ...